Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / scsi / pmcraid.c
diff --git a/kernel/drivers/scsi/pmcraid.c b/kernel/drivers/scsi/pmcraid.c
new file mode 100644 (file)
index 0000000..ed31d8c
--- /dev/null
@@ -0,0 +1,6061 @@
+/*
+ * pmcraid.c -- driver for PMC Sierra MaxRAID controller adapters
+ *
+ * Written By: Anil Ravindranath<anil_ravindranath@pmc-sierra.com>
+ *             PMC-Sierra Inc
+ *
+ * Copyright (C) 2008, 2009 PMC Sierra Inc
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307,
+ * USA
+ *
+ */
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/ioport.h>
+#include <linux/delay.h>
+#include <linux/pci.h>
+#include <linux/wait.h>
+#include <linux/spinlock.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/blkdev.h>
+#include <linux/firmware.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/hdreg.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <asm/irq.h>
+#include <asm/processor.h>
+#include <linux/libata.h>
+#include <linux/mutex.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsicam.h>
+
+#include "pmcraid.h"
+
+/*
+ *   Module configuration parameters
+ */
+static unsigned int pmcraid_debug_log;
+static unsigned int pmcraid_disable_aen;
+static unsigned int pmcraid_log_level = IOASC_LOG_LEVEL_MUST;
+static unsigned int pmcraid_enable_msix;
+
+/*
+ * Data structures to support multiple adapters by the LLD.
+ * pmcraid_adapter_count - count of configured adapters
+ */
+static atomic_t pmcraid_adapter_count = ATOMIC_INIT(0);
+
+/*
+ * Supporting user-level control interface through IOCTL commands.
+ * pmcraid_major - major number to use
+ * pmcraid_minor - minor number(s) to use
+ */
+static unsigned int pmcraid_major;
+static struct class *pmcraid_class;
+DECLARE_BITMAP(pmcraid_minor, PMCRAID_MAX_ADAPTERS);
+
+/*
+ * Module parameters
+ */
+MODULE_AUTHOR("Anil Ravindranath<anil_ravindranath@pmc-sierra.com>");
+MODULE_DESCRIPTION("PMC Sierra MaxRAID Controller Driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(PMCRAID_DRIVER_VERSION);
+
+module_param_named(log_level, pmcraid_log_level, uint, (S_IRUGO | S_IWUSR));
+MODULE_PARM_DESC(log_level,
+                "Enables firmware error code logging, default :1 high-severity"
+                " errors, 2: all errors including high-severity errors,"
+                " 0: disables logging");
+
+module_param_named(debug, pmcraid_debug_log, uint, (S_IRUGO | S_IWUSR));
+MODULE_PARM_DESC(debug,
+                "Enable driver verbose message logging. Set 1 to enable."
+                "(default: 0)");
+
+module_param_named(disable_aen, pmcraid_disable_aen, uint, (S_IRUGO | S_IWUSR));
+MODULE_PARM_DESC(disable_aen,
+                "Disable driver aen notifications to apps. Set 1 to disable."
+                "(default: 0)");
+
+/* chip specific constants for PMC MaxRAID controllers (same for
+ * 0x5220 and 0x8010
+ */
+static struct pmcraid_chip_details pmcraid_chip_cfg[] = {
+       {
+        .ioastatus = 0x0,
+        .ioarrin = 0x00040,
+        .mailbox = 0x7FC30,
+        .global_intr_mask = 0x00034,
+        .ioa_host_intr = 0x0009C,
+        .ioa_host_intr_clr = 0x000A0,
+        .ioa_host_msix_intr = 0x7FC40,
+        .ioa_host_mask = 0x7FC28,
+        .ioa_host_mask_clr = 0x7FC28,
+        .host_ioa_intr = 0x00020,
+        .host_ioa_intr_clr = 0x00020,
+        .transop_timeout = 300
+        }
+};
+
+/*
+ * PCI device ids supported by pmcraid driver
+ */
+static struct pci_device_id pmcraid_pci_table[] = {
+       { PCI_DEVICE(PCI_VENDOR_ID_PMC, PCI_DEVICE_ID_PMC_MAXRAID),
+         0, 0, (kernel_ulong_t)&pmcraid_chip_cfg[0]
+       },
+       {}
+};
+
+MODULE_DEVICE_TABLE(pci, pmcraid_pci_table);
+
+
+
+/**
+ * pmcraid_slave_alloc - Prepare for commands to a device
+ * @scsi_dev: scsi device struct
+ *
+ * This function is called by mid-layer prior to sending any command to the new
+ * device. Stores resource entry details of the device in scsi_device struct.
+ * Queuecommand uses the resource handle and other details to fill up IOARCB
+ * while sending commands to the device.
+ *
+ * Return value:
+ *       0 on success / -ENXIO if device does not exist
+ */
+static int pmcraid_slave_alloc(struct scsi_device *scsi_dev)
+{
+       struct pmcraid_resource_entry *temp, *res = NULL;
+       struct pmcraid_instance *pinstance;
+       u8 target, bus, lun;
+       unsigned long lock_flags;
+       int rc = -ENXIO;
+       u16 fw_version;
+
+       pinstance = shost_priv(scsi_dev->host);
+
+       fw_version = be16_to_cpu(pinstance->inq_data->fw_version);
+
+       /* Driver exposes VSET and GSCSI resources only; all other device types
+        * are not exposed. Resource list is synchronized using resource lock
+        * so any traversal or modifications to the list should be done inside
+        * this lock
+        */
+       spin_lock_irqsave(&pinstance->resource_lock, lock_flags);
+       list_for_each_entry(temp, &pinstance->used_res_q, queue) {
+
+               /* do not expose VSETs with order-ids > MAX_VSET_TARGETS */
+               if (RES_IS_VSET(temp->cfg_entry)) {
+                       if (fw_version <= PMCRAID_FW_VERSION_1)
+                               target = temp->cfg_entry.unique_flags1;
+                       else
+                               target = temp->cfg_entry.array_id & 0xFF;
+
+                       if (target > PMCRAID_MAX_VSET_TARGETS)
+                               continue;
+                       bus = PMCRAID_VSET_BUS_ID;
+                       lun = 0;
+               } else if (RES_IS_GSCSI(temp->cfg_entry)) {
+                       target = RES_TARGET(temp->cfg_entry.resource_address);
+                       bus = PMCRAID_PHYS_BUS_ID;
+                       lun = RES_LUN(temp->cfg_entry.resource_address);
+               } else {
+                       continue;
+               }
+
+               if (bus == scsi_dev->channel &&
+                   target == scsi_dev->id &&
+                   lun == scsi_dev->lun) {
+                       res = temp;
+                       break;
+               }
+       }
+
+       if (res) {
+               res->scsi_dev = scsi_dev;
+               scsi_dev->hostdata = res;
+               res->change_detected = 0;
+               atomic_set(&res->read_failures, 0);
+               atomic_set(&res->write_failures, 0);
+               rc = 0;
+       }
+       spin_unlock_irqrestore(&pinstance->resource_lock, lock_flags);
+       return rc;
+}
+
+/**
+ * pmcraid_slave_configure - Configures a SCSI device
+ * @scsi_dev: scsi device struct
+ *
+ * This function is executed by SCSI mid layer just after a device is first
+ * scanned (i.e. it has responded to an INQUIRY). For VSET resources, the
+ * timeout value (default 30s) will be over-written to a higher value (60s)
+ * and max_sectors value will be over-written to 512. It also sets queue depth
+ * to host->cmd_per_lun value
+ *
+ * Return value:
+ *       0 on success
+ */
+static int pmcraid_slave_configure(struct scsi_device *scsi_dev)
+{
+       struct pmcraid_resource_entry *res = scsi_dev->hostdata;
+
+       if (!res)
+               return 0;
+
+       /* LLD exposes VSETs and Enclosure devices only */
+       if (RES_IS_GSCSI(res->cfg_entry) &&
+           scsi_dev->type != TYPE_ENCLOSURE)
+               return -ENXIO;
+
+       pmcraid_info("configuring %x:%x:%x:%x\n",
+                    scsi_dev->host->unique_id,
+                    scsi_dev->channel,
+                    scsi_dev->id,
+                    (u8)scsi_dev->lun);
+
+       if (RES_IS_GSCSI(res->cfg_entry)) {
+               scsi_dev->allow_restart = 1;
+       } else if (RES_IS_VSET(res->cfg_entry)) {
+               scsi_dev->allow_restart = 1;
+               blk_queue_rq_timeout(scsi_dev->request_queue,
+                                    PMCRAID_VSET_IO_TIMEOUT);
+               blk_queue_max_hw_sectors(scsi_dev->request_queue,
+                                     PMCRAID_VSET_MAX_SECTORS);
+       }
+
+       /*
+        * We never want to report TCQ support for these types of devices.
+        */
+       if (!RES_IS_GSCSI(res->cfg_entry) && !RES_IS_VSET(res->cfg_entry))
+               scsi_dev->tagged_supported = 0;
+
+       return 0;
+}
+
+/**
+ * pmcraid_slave_destroy - Unconfigure a SCSI device before removing it
+ *
+ * @scsi_dev: scsi device struct
+ *
+ * This is called by mid-layer before removing a device. Pointer assignments
+ * done in pmcraid_slave_alloc will be reset to NULL here.
+ *
+ * Return value
+ *   none
+ */
+static void pmcraid_slave_destroy(struct scsi_device *scsi_dev)
+{
+       struct pmcraid_resource_entry *res;
+
+       res = (struct pmcraid_resource_entry *)scsi_dev->hostdata;
+
+       if (res)
+               res->scsi_dev = NULL;
+
+       scsi_dev->hostdata = NULL;
+}
+
+/**
+ * pmcraid_change_queue_depth - Change the device's queue depth
+ * @scsi_dev: scsi device struct
+ * @depth: depth to set
+ *
+ * Return value
+ *     actual depth set
+ */
+static int pmcraid_change_queue_depth(struct scsi_device *scsi_dev, int depth)
+{
+       if (depth > PMCRAID_MAX_CMD_PER_LUN)
+               depth = PMCRAID_MAX_CMD_PER_LUN;
+       return scsi_change_queue_depth(scsi_dev, depth);
+}
+
+/**
+ * pmcraid_init_cmdblk - initializes a command block
+ *
+ * @cmd: pointer to struct pmcraid_cmd to be initialized
+ * @index: if >=0 first time initialization; otherwise reinitialization
+ *
+ * Return Value
+ *      None
+ */
+void pmcraid_init_cmdblk(struct pmcraid_cmd *cmd, int index)
+{
+       struct pmcraid_ioarcb *ioarcb = &(cmd->ioa_cb->ioarcb);
+       dma_addr_t dma_addr = cmd->ioa_cb_bus_addr;
+
+       if (index >= 0) {
+               /* first time initialization (called from  probe) */
+               u32 ioasa_offset =
+                       offsetof(struct pmcraid_control_block, ioasa);
+
+               cmd->index = index;
+               ioarcb->response_handle = cpu_to_le32(index << 2);
+               ioarcb->ioarcb_bus_addr = cpu_to_le64(dma_addr);
+               ioarcb->ioasa_bus_addr = cpu_to_le64(dma_addr + ioasa_offset);
+               ioarcb->ioasa_len = cpu_to_le16(sizeof(struct pmcraid_ioasa));
+       } else {
+               /* re-initialization of various lengths, called once command is
+                * processed by IOA
+                */
+               memset(&cmd->ioa_cb->ioarcb.cdb, 0, PMCRAID_MAX_CDB_LEN);
+               ioarcb->hrrq_id = 0;
+               ioarcb->request_flags0 = 0;
+               ioarcb->request_flags1 = 0;
+               ioarcb->cmd_timeout = 0;
+               ioarcb->ioarcb_bus_addr &= (~0x1FULL);
+               ioarcb->ioadl_bus_addr = 0;
+               ioarcb->ioadl_length = 0;
+               ioarcb->data_transfer_length = 0;
+               ioarcb->add_cmd_param_length = 0;
+               ioarcb->add_cmd_param_offset = 0;
+               cmd->ioa_cb->ioasa.ioasc = 0;
+               cmd->ioa_cb->ioasa.residual_data_length = 0;
+               cmd->time_left = 0;
+       }
+
+       cmd->cmd_done = NULL;
+       cmd->scsi_cmd = NULL;
+       cmd->release = 0;
+       cmd->completion_req = 0;
+       cmd->sense_buffer = 0;
+       cmd->sense_buffer_dma = 0;
+       cmd->dma_handle = 0;
+       init_timer(&cmd->timer);
+}
+
+/**
+ * pmcraid_reinit_cmdblk - reinitialize a command block
+ *
+ * @cmd: pointer to struct pmcraid_cmd to be reinitialized
+ *
+ * Return Value
+ *      None
+ */
+static void pmcraid_reinit_cmdblk(struct pmcraid_cmd *cmd)
+{
+       pmcraid_init_cmdblk(cmd, -1);
+}
+
+/**
+ * pmcraid_get_free_cmd - get a free cmd block from command block pool
+ * @pinstance: adapter instance structure
+ *
+ * Return Value:
+ *     returns pointer to cmd block or NULL if no blocks are available
+ */
+static struct pmcraid_cmd *pmcraid_get_free_cmd(
+       struct pmcraid_instance *pinstance
+)
+{
+       struct pmcraid_cmd *cmd = NULL;
+       unsigned long lock_flags;
+
+       /* free cmd block list is protected by free_pool_lock */
+       spin_lock_irqsave(&pinstance->free_pool_lock, lock_flags);
+
+       if (!list_empty(&pinstance->free_cmd_pool)) {
+               cmd = list_entry(pinstance->free_cmd_pool.next,
+                                struct pmcraid_cmd, free_list);
+               list_del(&cmd->free_list);
+       }
+       spin_unlock_irqrestore(&pinstance->free_pool_lock, lock_flags);
+
+       /* Initialize the command block before giving it the caller */
+       if (cmd != NULL)
+               pmcraid_reinit_cmdblk(cmd);
+       return cmd;
+}
+
+/**
+ * pmcraid_return_cmd - return a completed command block back into free pool
+ * @cmd: pointer to the command block
+ *
+ * Return Value:
+ *     nothing
+ */
+void pmcraid_return_cmd(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       unsigned long lock_flags;
+
+       spin_lock_irqsave(&pinstance->free_pool_lock, lock_flags);
+       list_add_tail(&cmd->free_list, &pinstance->free_cmd_pool);
+       spin_unlock_irqrestore(&pinstance->free_pool_lock, lock_flags);
+}
+
+/**
+ * pmcraid_read_interrupts -  reads IOA interrupts
+ *
+ * @pinstance: pointer to adapter instance structure
+ *
+ * Return value
+ *      interrupts read from IOA
+ */
+static u32 pmcraid_read_interrupts(struct pmcraid_instance *pinstance)
+{
+       return (pinstance->interrupt_mode) ?
+               ioread32(pinstance->int_regs.ioa_host_msix_interrupt_reg) :
+               ioread32(pinstance->int_regs.ioa_host_interrupt_reg);
+}
+
+/**
+ * pmcraid_disable_interrupts - Masks and clears all specified interrupts
+ *
+ * @pinstance: pointer to per adapter instance structure
+ * @intrs: interrupts to disable
+ *
+ * Return Value
+ *      None
+ */
+static void pmcraid_disable_interrupts(
+       struct pmcraid_instance *pinstance,
+       u32 intrs
+)
+{
+       u32 gmask = ioread32(pinstance->int_regs.global_interrupt_mask_reg);
+       u32 nmask = gmask | GLOBAL_INTERRUPT_MASK;
+
+       iowrite32(intrs, pinstance->int_regs.ioa_host_interrupt_clr_reg);
+       iowrite32(nmask, pinstance->int_regs.global_interrupt_mask_reg);
+       ioread32(pinstance->int_regs.global_interrupt_mask_reg);
+
+       if (!pinstance->interrupt_mode) {
+               iowrite32(intrs,
+                       pinstance->int_regs.ioa_host_interrupt_mask_reg);
+               ioread32(pinstance->int_regs.ioa_host_interrupt_mask_reg);
+       }
+}
+
+/**
+ * pmcraid_enable_interrupts - Enables specified interrupts
+ *
+ * @pinstance: pointer to per adapter instance structure
+ * @intr: interrupts to enable
+ *
+ * Return Value
+ *      None
+ */
+static void pmcraid_enable_interrupts(
+       struct pmcraid_instance *pinstance,
+       u32 intrs
+)
+{
+       u32 gmask = ioread32(pinstance->int_regs.global_interrupt_mask_reg);
+       u32 nmask = gmask & (~GLOBAL_INTERRUPT_MASK);
+
+       iowrite32(nmask, pinstance->int_regs.global_interrupt_mask_reg);
+
+       if (!pinstance->interrupt_mode) {
+               iowrite32(~intrs,
+                        pinstance->int_regs.ioa_host_interrupt_mask_reg);
+               ioread32(pinstance->int_regs.ioa_host_interrupt_mask_reg);
+       }
+
+       pmcraid_info("enabled interrupts global mask = %x intr_mask = %x\n",
+               ioread32(pinstance->int_regs.global_interrupt_mask_reg),
+               ioread32(pinstance->int_regs.ioa_host_interrupt_mask_reg));
+}
+
+/**
+ * pmcraid_clr_trans_op - clear trans to op interrupt
+ *
+ * @pinstance: pointer to per adapter instance structure
+ *
+ * Return Value
+ *      None
+ */
+static void pmcraid_clr_trans_op(
+       struct pmcraid_instance *pinstance
+)
+{
+       unsigned long lock_flags;
+
+       if (!pinstance->interrupt_mode) {
+               iowrite32(INTRS_TRANSITION_TO_OPERATIONAL,
+                       pinstance->int_regs.ioa_host_interrupt_mask_reg);
+               ioread32(pinstance->int_regs.ioa_host_interrupt_mask_reg);
+               iowrite32(INTRS_TRANSITION_TO_OPERATIONAL,
+                       pinstance->int_regs.ioa_host_interrupt_clr_reg);
+               ioread32(pinstance->int_regs.ioa_host_interrupt_clr_reg);
+       }
+
+       if (pinstance->reset_cmd != NULL) {
+               del_timer(&pinstance->reset_cmd->timer);
+               spin_lock_irqsave(
+                       pinstance->host->host_lock, lock_flags);
+               pinstance->reset_cmd->cmd_done(pinstance->reset_cmd);
+               spin_unlock_irqrestore(
+                       pinstance->host->host_lock, lock_flags);
+       }
+}
+
+/**
+ * pmcraid_reset_type - Determine the required reset type
+ * @pinstance: pointer to adapter instance structure
+ *
+ * IOA requires hard reset if any of the following conditions is true.
+ * 1. If HRRQ valid interrupt is not masked
+ * 2. IOA reset alert doorbell is set
+ * 3. If there are any error interrupts
+ */
+static void pmcraid_reset_type(struct pmcraid_instance *pinstance)
+{
+       u32 mask;
+       u32 intrs;
+       u32 alerts;
+
+       mask = ioread32(pinstance->int_regs.ioa_host_interrupt_mask_reg);
+       intrs = ioread32(pinstance->int_regs.ioa_host_interrupt_reg);
+       alerts = ioread32(pinstance->int_regs.host_ioa_interrupt_reg);
+
+       if ((mask & INTRS_HRRQ_VALID) == 0 ||
+           (alerts & DOORBELL_IOA_RESET_ALERT) ||
+           (intrs & PMCRAID_ERROR_INTERRUPTS)) {
+               pmcraid_info("IOA requires hard reset\n");
+               pinstance->ioa_hard_reset = 1;
+       }
+
+       /* If unit check is active, trigger the dump */
+       if (intrs & INTRS_IOA_UNIT_CHECK)
+               pinstance->ioa_unit_check = 1;
+}
+
+/**
+ * pmcraid_bist_done - completion function for PCI BIST
+ * @cmd: pointer to reset command
+ * Return Value
+ *     none
+ */
+
+static void pmcraid_ioa_reset(struct pmcraid_cmd *);
+
+static void pmcraid_bist_done(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       unsigned long lock_flags;
+       int rc;
+       u16 pci_reg;
+
+       rc = pci_read_config_word(pinstance->pdev, PCI_COMMAND, &pci_reg);
+
+       /* If PCI config space can't be accessed wait for another two secs */
+       if ((rc != PCIBIOS_SUCCESSFUL || (!(pci_reg & PCI_COMMAND_MEMORY))) &&
+           cmd->time_left > 0) {
+               pmcraid_info("BIST not complete, waiting another 2 secs\n");
+               cmd->timer.expires = jiffies + cmd->time_left;
+               cmd->time_left = 0;
+               cmd->timer.data = (unsigned long)cmd;
+               cmd->timer.function =
+                       (void (*)(unsigned long))pmcraid_bist_done;
+               add_timer(&cmd->timer);
+       } else {
+               cmd->time_left = 0;
+               pmcraid_info("BIST is complete, proceeding with reset\n");
+               spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+               pmcraid_ioa_reset(cmd);
+               spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+       }
+}
+
+/**
+ * pmcraid_start_bist - starts BIST
+ * @cmd: pointer to reset cmd
+ * Return Value
+ *   none
+ */
+static void pmcraid_start_bist(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       u32 doorbells, intrs;
+
+       /* proceed with bist and wait for 2 seconds */
+       iowrite32(DOORBELL_IOA_START_BIST,
+               pinstance->int_regs.host_ioa_interrupt_reg);
+       doorbells = ioread32(pinstance->int_regs.host_ioa_interrupt_reg);
+       intrs = ioread32(pinstance->int_regs.ioa_host_interrupt_reg);
+       pmcraid_info("doorbells after start bist: %x intrs: %x\n",
+                     doorbells, intrs);
+
+       cmd->time_left = msecs_to_jiffies(PMCRAID_BIST_TIMEOUT);
+       cmd->timer.data = (unsigned long)cmd;
+       cmd->timer.expires = jiffies + msecs_to_jiffies(PMCRAID_BIST_TIMEOUT);
+       cmd->timer.function = (void (*)(unsigned long))pmcraid_bist_done;
+       add_timer(&cmd->timer);
+}
+
+/**
+ * pmcraid_reset_alert_done - completion routine for reset_alert
+ * @cmd: pointer to command block used in reset sequence
+ * Return value
+ *  None
+ */
+static void pmcraid_reset_alert_done(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       u32 status = ioread32(pinstance->ioa_status);
+       unsigned long lock_flags;
+
+       /* if the critical operation in progress bit is set or the wait times
+        * out, invoke reset engine to proceed with hard reset. If there is
+        * some more time to wait, restart the timer
+        */
+       if (((status & INTRS_CRITICAL_OP_IN_PROGRESS) == 0) ||
+           cmd->time_left <= 0) {
+               pmcraid_info("critical op is reset proceeding with reset\n");
+               spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+               pmcraid_ioa_reset(cmd);
+               spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+       } else {
+               pmcraid_info("critical op is not yet reset waiting again\n");
+               /* restart timer if some more time is available to wait */
+               cmd->time_left -= PMCRAID_CHECK_FOR_RESET_TIMEOUT;
+               cmd->timer.data = (unsigned long)cmd;
+               cmd->timer.expires = jiffies + PMCRAID_CHECK_FOR_RESET_TIMEOUT;
+               cmd->timer.function =
+                       (void (*)(unsigned long))pmcraid_reset_alert_done;
+               add_timer(&cmd->timer);
+       }
+}
+
+/**
+ * pmcraid_reset_alert - alerts IOA for a possible reset
+ * @cmd : command block to be used for reset sequence.
+ *
+ * Return Value
+ *     returns 0 if pci config-space is accessible and RESET_DOORBELL is
+ *     successfully written to IOA. Returns non-zero in case pci_config_space
+ *     is not accessible
+ */
+static void pmcraid_notify_ioastate(struct pmcraid_instance *, u32);
+static void pmcraid_reset_alert(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       u32 doorbells;
+       int rc;
+       u16 pci_reg;
+
+       /* If we are able to access IOA PCI config space, alert IOA that we are
+        * going to reset it soon. This enables IOA to preserv persistent error
+        * data if any. In case memory space is not accessible, proceed with
+        * BIST or slot_reset
+        */
+       rc = pci_read_config_word(pinstance->pdev, PCI_COMMAND, &pci_reg);
+       if ((rc == PCIBIOS_SUCCESSFUL) && (pci_reg & PCI_COMMAND_MEMORY)) {
+
+               /* wait for IOA permission i.e until CRITICAL_OPERATION bit is
+                * reset IOA doesn't generate any interrupts when CRITICAL
+                * OPERATION bit is reset. A timer is started to wait for this
+                * bit to be reset.
+                */
+               cmd->time_left = PMCRAID_RESET_TIMEOUT;
+               cmd->timer.data = (unsigned long)cmd;
+               cmd->timer.expires = jiffies + PMCRAID_CHECK_FOR_RESET_TIMEOUT;
+               cmd->timer.function =
+                       (void (*)(unsigned long))pmcraid_reset_alert_done;
+               add_timer(&cmd->timer);
+
+               iowrite32(DOORBELL_IOA_RESET_ALERT,
+                       pinstance->int_regs.host_ioa_interrupt_reg);
+               doorbells =
+                       ioread32(pinstance->int_regs.host_ioa_interrupt_reg);
+               pmcraid_info("doorbells after reset alert: %x\n", doorbells);
+       } else {
+               pmcraid_info("PCI config is not accessible starting BIST\n");
+               pinstance->ioa_state = IOA_STATE_IN_HARD_RESET;
+               pmcraid_start_bist(cmd);
+       }
+}
+
+/**
+ * pmcraid_timeout_handler -  Timeout handler for internally generated ops
+ *
+ * @cmd : pointer to command structure, that got timedout
+ *
+ * This function blocks host requests and initiates an adapter reset.
+ *
+ * Return value:
+ *   None
+ */
+static void pmcraid_timeout_handler(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       unsigned long lock_flags;
+
+       dev_info(&pinstance->pdev->dev,
+               "Adapter being reset due to cmd(CDB[0] = %x) timeout\n",
+               cmd->ioa_cb->ioarcb.cdb[0]);
+
+       /* Command timeouts result in hard reset sequence. The command that got
+        * timed out may be the one used as part of reset sequence. In this
+        * case restart reset sequence using the same command block even if
+        * reset is in progress. Otherwise fail this command and get a free
+        * command block to restart the reset sequence.
+        */
+       spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+       if (!pinstance->ioa_reset_in_progress) {
+               pinstance->ioa_reset_attempts = 0;
+               cmd = pmcraid_get_free_cmd(pinstance);
+
+               /* If we are out of command blocks, just return here itself.
+                * Some other command's timeout handler can do the reset job
+                */
+               if (cmd == NULL) {
+                       spin_unlock_irqrestore(pinstance->host->host_lock,
+                                              lock_flags);
+                       pmcraid_err("no free cmnd block for timeout handler\n");
+                       return;
+               }
+
+               pinstance->reset_cmd = cmd;
+               pinstance->ioa_reset_in_progress = 1;
+       } else {
+               pmcraid_info("reset is already in progress\n");
+
+               if (pinstance->reset_cmd != cmd) {
+                       /* This command should have been given to IOA, this
+                        * command will be completed by fail_outstanding_cmds
+                        * anyway
+                        */
+                       pmcraid_err("cmd is pending but reset in progress\n");
+               }
+
+               /* If this command was being used as part of the reset
+                * sequence, set cmd_done pointer to pmcraid_ioa_reset. This
+                * causes fail_outstanding_commands not to return the command
+                * block back to free pool
+                */
+               if (cmd == pinstance->reset_cmd)
+                       cmd->cmd_done = pmcraid_ioa_reset;
+       }
+
+       /* Notify apps of important IOA bringup/bringdown sequences */
+       if (pinstance->scn.ioa_state != PMC_DEVICE_EVENT_RESET_START &&
+           pinstance->scn.ioa_state != PMC_DEVICE_EVENT_SHUTDOWN_START)
+               pmcraid_notify_ioastate(pinstance,
+                                       PMC_DEVICE_EVENT_RESET_START);
+
+       pinstance->ioa_state = IOA_STATE_IN_RESET_ALERT;
+       scsi_block_requests(pinstance->host);
+       pmcraid_reset_alert(cmd);
+       spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+}
+
+/**
+ * pmcraid_internal_done - completion routine for internally generated cmds
+ *
+ * @cmd: command that got response from IOA
+ *
+ * Return Value:
+ *      none
+ */
+static void pmcraid_internal_done(struct pmcraid_cmd *cmd)
+{
+       pmcraid_info("response internal cmd CDB[0] = %x ioasc = %x\n",
+                    cmd->ioa_cb->ioarcb.cdb[0],
+                    le32_to_cpu(cmd->ioa_cb->ioasa.ioasc));
+
+       /* Some of the internal commands are sent with callers blocking for the
+        * response. Same will be indicated as part of cmd->completion_req
+        * field. Response path needs to wake up any waiters waiting for cmd
+        * completion if this flag is set.
+        */
+       if (cmd->completion_req) {
+               cmd->completion_req = 0;
+               complete(&cmd->wait_for_completion);
+       }
+
+       /* most of the internal commands are completed by caller itself, so
+        * no need to return the command block back to free pool until we are
+        * required to do so (e.g once done with initialization).
+        */
+       if (cmd->release) {
+               cmd->release = 0;
+               pmcraid_return_cmd(cmd);
+       }
+}
+
+/**
+ * pmcraid_reinit_cfgtable_done - done function for cfg table reinitialization
+ *
+ * @cmd: command that got response from IOA
+ *
+ * This routine is called after driver re-reads configuration table due to a
+ * lost CCN. It returns the command block back to free pool and schedules
+ * worker thread to add/delete devices into the system.
+ *
+ * Return Value:
+ *      none
+ */
+static void pmcraid_reinit_cfgtable_done(struct pmcraid_cmd *cmd)
+{
+       pmcraid_info("response internal cmd CDB[0] = %x ioasc = %x\n",
+                    cmd->ioa_cb->ioarcb.cdb[0],
+                    le32_to_cpu(cmd->ioa_cb->ioasa.ioasc));
+
+       if (cmd->release) {
+               cmd->release = 0;
+               pmcraid_return_cmd(cmd);
+       }
+       pmcraid_info("scheduling worker for config table reinitialization\n");
+       schedule_work(&cmd->drv_inst->worker_q);
+}
+
+/**
+ * pmcraid_erp_done - Process completion of SCSI error response from device
+ * @cmd: pmcraid_command
+ *
+ * This function copies the sense buffer into the scsi_cmd struct and completes
+ * scsi_cmd by calling scsi_done function.
+ *
+ * Return value:
+ *  none
+ */
+static void pmcraid_erp_done(struct pmcraid_cmd *cmd)
+{
+       struct scsi_cmnd *scsi_cmd = cmd->scsi_cmd;
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       u32 ioasc = le32_to_cpu(cmd->ioa_cb->ioasa.ioasc);
+
+       if (PMCRAID_IOASC_SENSE_KEY(ioasc) > 0) {
+               scsi_cmd->result |= (DID_ERROR << 16);
+               scmd_printk(KERN_INFO, scsi_cmd,
+                           "command CDB[0] = %x failed with IOASC: 0x%08X\n",
+                           cmd->ioa_cb->ioarcb.cdb[0], ioasc);
+       }
+
+       /* if we had allocated sense buffers for request sense, copy the sense
+        * release the buffers
+        */
+       if (cmd->sense_buffer != NULL) {
+               memcpy(scsi_cmd->sense_buffer,
+                      cmd->sense_buffer,
+                      SCSI_SENSE_BUFFERSIZE);
+               pci_free_consistent(pinstance->pdev,
+                                   SCSI_SENSE_BUFFERSIZE,
+                                   cmd->sense_buffer, cmd->sense_buffer_dma);
+               cmd->sense_buffer = NULL;
+               cmd->sense_buffer_dma = 0;
+       }
+
+       scsi_dma_unmap(scsi_cmd);
+       pmcraid_return_cmd(cmd);
+       scsi_cmd->scsi_done(scsi_cmd);
+}
+
+/**
+ * pmcraid_fire_command - sends an IOA command to adapter
+ *
+ * This function adds the given block into pending command list
+ * and returns without waiting
+ *
+ * @cmd : command to be sent to the device
+ *
+ * Return Value
+ *     None
+ */
+static void _pmcraid_fire_command(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       unsigned long lock_flags;
+
+       /* Add this command block to pending cmd pool. We do this prior to
+        * writting IOARCB to ioarrin because IOA might complete the command
+        * by the time we are about to add it to the list. Response handler
+        * (isr/tasklet) looks for cmd block in the pending pending list.
+        */
+       spin_lock_irqsave(&pinstance->pending_pool_lock, lock_flags);
+       list_add_tail(&cmd->free_list, &pinstance->pending_cmd_pool);
+       spin_unlock_irqrestore(&pinstance->pending_pool_lock, lock_flags);
+       atomic_inc(&pinstance->outstanding_cmds);
+
+       /* driver writes lower 32-bit value of IOARCB address only */
+       mb();
+       iowrite32(le32_to_cpu(cmd->ioa_cb->ioarcb.ioarcb_bus_addr),
+                 pinstance->ioarrin);
+}
+
+/**
+ * pmcraid_send_cmd - fires a command to IOA
+ *
+ * This function also sets up timeout function, and command completion
+ * function
+ *
+ * @cmd: pointer to the command block to be fired to IOA
+ * @cmd_done: command completion function, called once IOA responds
+ * @timeout: timeout to wait for this command completion
+ * @timeout_func: timeout handler
+ *
+ * Return value
+ *   none
+ */
+static void pmcraid_send_cmd(
+       struct pmcraid_cmd *cmd,
+       void (*cmd_done) (struct pmcraid_cmd *),
+       unsigned long timeout,
+       void (*timeout_func) (struct pmcraid_cmd *)
+)
+{
+       /* initialize done function */
+       cmd->cmd_done = cmd_done;
+
+       if (timeout_func) {
+               /* setup timeout handler */
+               cmd->timer.data = (unsigned long)cmd;
+               cmd->timer.expires = jiffies + timeout;
+               cmd->timer.function = (void (*)(unsigned long))timeout_func;
+               add_timer(&cmd->timer);
+       }
+
+       /* fire the command to IOA */
+       _pmcraid_fire_command(cmd);
+}
+
+/**
+ * pmcraid_ioa_shutdown_done - completion function for IOA shutdown command
+ * @cmd: pointer to the command block used for sending IOA shutdown command
+ *
+ * Return value
+ *  None
+ */
+static void pmcraid_ioa_shutdown_done(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       unsigned long lock_flags;
+
+       spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+       pmcraid_ioa_reset(cmd);
+       spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+}
+
+/**
+ * pmcraid_ioa_shutdown - sends SHUTDOWN command to ioa
+ *
+ * @cmd: pointer to the command block used as part of reset sequence
+ *
+ * Return Value
+ *  None
+ */
+static void pmcraid_ioa_shutdown(struct pmcraid_cmd *cmd)
+{
+       pmcraid_info("response for Cancel CCN CDB[0] = %x ioasc = %x\n",
+                    cmd->ioa_cb->ioarcb.cdb[0],
+                    le32_to_cpu(cmd->ioa_cb->ioasa.ioasc));
+
+       /* Note that commands sent during reset require next command to be sent
+        * to IOA. Hence reinit the done function as well as timeout function
+        */
+       pmcraid_reinit_cmdblk(cmd);
+       cmd->ioa_cb->ioarcb.request_type = REQ_TYPE_IOACMD;
+       cmd->ioa_cb->ioarcb.resource_handle =
+               cpu_to_le32(PMCRAID_IOA_RES_HANDLE);
+       cmd->ioa_cb->ioarcb.cdb[0] = PMCRAID_IOA_SHUTDOWN;
+       cmd->ioa_cb->ioarcb.cdb[1] = PMCRAID_SHUTDOWN_NORMAL;
+
+       /* fire shutdown command to hardware. */
+       pmcraid_info("firing normal shutdown command (%d) to IOA\n",
+                    le32_to_cpu(cmd->ioa_cb->ioarcb.response_handle));
+
+       pmcraid_notify_ioastate(cmd->drv_inst, PMC_DEVICE_EVENT_SHUTDOWN_START);
+
+       pmcraid_send_cmd(cmd, pmcraid_ioa_shutdown_done,
+                        PMCRAID_SHUTDOWN_TIMEOUT,
+                        pmcraid_timeout_handler);
+}
+
+/**
+ * pmcraid_get_fwversion_done - completion function for get_fwversion
+ *
+ * @cmd: pointer to command block used to send INQUIRY command
+ *
+ * Return Value
+ *     none
+ */
+static void pmcraid_querycfg(struct pmcraid_cmd *);
+
+static void pmcraid_get_fwversion_done(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       u32 ioasc = le32_to_cpu(cmd->ioa_cb->ioasa.ioasc);
+       unsigned long lock_flags;
+
+       /* configuration table entry size depends on firmware version. If fw
+        * version is not known, it is not possible to interpret IOA config
+        * table
+        */
+       if (ioasc) {
+               pmcraid_err("IOA Inquiry failed with %x\n", ioasc);
+               spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+               pinstance->ioa_state = IOA_STATE_IN_RESET_ALERT;
+               pmcraid_reset_alert(cmd);
+               spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+       } else  {
+               pmcraid_querycfg(cmd);
+       }
+}
+
+/**
+ * pmcraid_get_fwversion - reads firmware version information
+ *
+ * @cmd: pointer to command block used to send INQUIRY command
+ *
+ * Return Value
+ *     none
+ */
+static void pmcraid_get_fwversion(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
+       struct pmcraid_ioadl_desc *ioadl = ioarcb->add_data.u.ioadl;
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       u16 data_size = sizeof(struct pmcraid_inquiry_data);
+
+       pmcraid_reinit_cmdblk(cmd);
+       ioarcb->request_type = REQ_TYPE_SCSI;
+       ioarcb->resource_handle = cpu_to_le32(PMCRAID_IOA_RES_HANDLE);
+       ioarcb->cdb[0] = INQUIRY;
+       ioarcb->cdb[1] = 1;
+       ioarcb->cdb[2] = 0xD0;
+       ioarcb->cdb[3] = (data_size >> 8) & 0xFF;
+       ioarcb->cdb[4] = data_size & 0xFF;
+
+       /* Since entire inquiry data it can be part of IOARCB itself
+        */
+       ioarcb->ioadl_bus_addr = cpu_to_le64((cmd->ioa_cb_bus_addr) +
+                                       offsetof(struct pmcraid_ioarcb,
+                                               add_data.u.ioadl[0]));
+       ioarcb->ioadl_length = cpu_to_le32(sizeof(struct pmcraid_ioadl_desc));
+       ioarcb->ioarcb_bus_addr &= ~(0x1FULL);
+
+       ioarcb->request_flags0 |= NO_LINK_DESCS;
+       ioarcb->data_transfer_length = cpu_to_le32(data_size);
+       ioadl = &(ioarcb->add_data.u.ioadl[0]);
+       ioadl->flags = IOADL_FLAGS_LAST_DESC;
+       ioadl->address = cpu_to_le64(pinstance->inq_data_baddr);
+       ioadl->data_len = cpu_to_le32(data_size);
+
+       pmcraid_send_cmd(cmd, pmcraid_get_fwversion_done,
+                        PMCRAID_INTERNAL_TIMEOUT, pmcraid_timeout_handler);
+}
+
+/**
+ * pmcraid_identify_hrrq - registers host rrq buffers with IOA
+ * @cmd: pointer to command block to be used for identify hrrq
+ *
+ * Return Value
+ *      none
+ */
+static void pmcraid_identify_hrrq(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
+       int index = cmd->hrrq_index;
+       __be64 hrrq_addr = cpu_to_be64(pinstance->hrrq_start_bus_addr[index]);
+       u32 hrrq_size = cpu_to_be32(sizeof(u32) * PMCRAID_MAX_CMD);
+       void (*done_function)(struct pmcraid_cmd *);
+
+       pmcraid_reinit_cmdblk(cmd);
+       cmd->hrrq_index = index + 1;
+
+       if (cmd->hrrq_index < pinstance->num_hrrq) {
+               done_function = pmcraid_identify_hrrq;
+       } else {
+               cmd->hrrq_index = 0;
+               done_function = pmcraid_get_fwversion;
+       }
+
+       /* Initialize ioarcb */
+       ioarcb->request_type = REQ_TYPE_IOACMD;
+       ioarcb->resource_handle = cpu_to_le32(PMCRAID_IOA_RES_HANDLE);
+
+       /* initialize the hrrq number where IOA will respond to this command */
+       ioarcb->hrrq_id = index;
+       ioarcb->cdb[0] = PMCRAID_IDENTIFY_HRRQ;
+       ioarcb->cdb[1] = index;
+
+       /* IOA expects 64-bit pci address to be written in B.E format
+        * (i.e cdb[2]=MSByte..cdb[9]=LSB.
+        */
+       pmcraid_info("HRRQ_IDENTIFY with hrrq:ioarcb:index => %llx:%llx:%x\n",
+                    hrrq_addr, ioarcb->ioarcb_bus_addr, index);
+
+       memcpy(&(ioarcb->cdb[2]), &hrrq_addr, sizeof(hrrq_addr));
+       memcpy(&(ioarcb->cdb[10]), &hrrq_size, sizeof(hrrq_size));
+
+       /* Subsequent commands require HRRQ identification to be successful.
+        * Note that this gets called even during reset from SCSI mid-layer
+        * or tasklet
+        */
+       pmcraid_send_cmd(cmd, done_function,
+                        PMCRAID_INTERNAL_TIMEOUT,
+                        pmcraid_timeout_handler);
+}
+
+static void pmcraid_process_ccn(struct pmcraid_cmd *cmd);
+static void pmcraid_process_ldn(struct pmcraid_cmd *cmd);
+
+/**
+ * pmcraid_send_hcam_cmd - send an initialized command block(HCAM) to IOA
+ *
+ * @cmd: initialized command block pointer
+ *
+ * Return Value
+ *   none
+ */
+static void pmcraid_send_hcam_cmd(struct pmcraid_cmd *cmd)
+{
+       if (cmd->ioa_cb->ioarcb.cdb[1] == PMCRAID_HCAM_CODE_CONFIG_CHANGE)
+               atomic_set(&(cmd->drv_inst->ccn.ignore), 0);
+       else
+               atomic_set(&(cmd->drv_inst->ldn.ignore), 0);
+
+       pmcraid_send_cmd(cmd, cmd->cmd_done, 0, NULL);
+}
+
+/**
+ * pmcraid_init_hcam - send an initialized command block(HCAM) to IOA
+ *
+ * @pinstance: pointer to adapter instance structure
+ * @type: HCAM type
+ *
+ * Return Value
+ *   pointer to initialized pmcraid_cmd structure or NULL
+ */
+static struct pmcraid_cmd *pmcraid_init_hcam
+(
+       struct pmcraid_instance *pinstance,
+       u8 type
+)
+{
+       struct pmcraid_cmd *cmd;
+       struct pmcraid_ioarcb *ioarcb;
+       struct pmcraid_ioadl_desc *ioadl;
+       struct pmcraid_hostrcb *hcam;
+       void (*cmd_done) (struct pmcraid_cmd *);
+       dma_addr_t dma;
+       int rcb_size;
+
+       cmd = pmcraid_get_free_cmd(pinstance);
+
+       if (!cmd) {
+               pmcraid_err("no free command blocks for hcam\n");
+               return cmd;
+       }
+
+       if (type == PMCRAID_HCAM_CODE_CONFIG_CHANGE) {
+               rcb_size = sizeof(struct pmcraid_hcam_ccn_ext);
+               cmd_done = pmcraid_process_ccn;
+               dma = pinstance->ccn.baddr + PMCRAID_AEN_HDR_SIZE;
+               hcam = &pinstance->ccn;
+       } else {
+               rcb_size = sizeof(struct pmcraid_hcam_ldn);
+               cmd_done = pmcraid_process_ldn;
+               dma = pinstance->ldn.baddr + PMCRAID_AEN_HDR_SIZE;
+               hcam = &pinstance->ldn;
+       }
+
+       /* initialize command pointer used for HCAM registration */
+       hcam->cmd = cmd;
+
+       ioarcb = &cmd->ioa_cb->ioarcb;
+       ioarcb->ioadl_bus_addr = cpu_to_le64((cmd->ioa_cb_bus_addr) +
+                                       offsetof(struct pmcraid_ioarcb,
+                                               add_data.u.ioadl[0]));
+       ioarcb->ioadl_length = cpu_to_le32(sizeof(struct pmcraid_ioadl_desc));
+       ioadl = ioarcb->add_data.u.ioadl;
+
+       /* Initialize ioarcb */
+       ioarcb->request_type = REQ_TYPE_HCAM;
+       ioarcb->resource_handle = cpu_to_le32(PMCRAID_IOA_RES_HANDLE);
+       ioarcb->cdb[0] = PMCRAID_HOST_CONTROLLED_ASYNC;
+       ioarcb->cdb[1] = type;
+       ioarcb->cdb[7] = (rcb_size >> 8) & 0xFF;
+       ioarcb->cdb[8] = (rcb_size) & 0xFF;
+
+       ioarcb->data_transfer_length = cpu_to_le32(rcb_size);
+
+       ioadl[0].flags |= IOADL_FLAGS_READ_LAST;
+       ioadl[0].data_len = cpu_to_le32(rcb_size);
+       ioadl[0].address = cpu_to_le32(dma);
+
+       cmd->cmd_done = cmd_done;
+       return cmd;
+}
+
+/**
+ * pmcraid_send_hcam - Send an HCAM to IOA
+ * @pinstance: ioa config struct
+ * @type: HCAM type
+ *
+ * This function will send a Host Controlled Async command to IOA.
+ *
+ * Return value:
+ *     none
+ */
+static void pmcraid_send_hcam(struct pmcraid_instance *pinstance, u8 type)
+{
+       struct pmcraid_cmd *cmd = pmcraid_init_hcam(pinstance, type);
+       pmcraid_send_hcam_cmd(cmd);
+}
+
+
+/**
+ * pmcraid_prepare_cancel_cmd - prepares a command block to abort another
+ *
+ * @cmd: pointer to cmd that is used as cancelling command
+ * @cmd_to_cancel: pointer to the command that needs to be cancelled
+ */
+static void pmcraid_prepare_cancel_cmd(
+       struct pmcraid_cmd *cmd,
+       struct pmcraid_cmd *cmd_to_cancel
+)
+{
+       struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
+       __be64 ioarcb_addr = cmd_to_cancel->ioa_cb->ioarcb.ioarcb_bus_addr;
+
+       /* Get the resource handle to where the command to be aborted has been
+        * sent.
+        */
+       ioarcb->resource_handle = cmd_to_cancel->ioa_cb->ioarcb.resource_handle;
+       ioarcb->request_type = REQ_TYPE_IOACMD;
+       memset(ioarcb->cdb, 0, PMCRAID_MAX_CDB_LEN);
+       ioarcb->cdb[0] = PMCRAID_ABORT_CMD;
+
+       /* IOARCB address of the command to be cancelled is given in
+        * cdb[2]..cdb[9] is Big-Endian format. Note that length bits in
+        * IOARCB address are not masked.
+        */
+       ioarcb_addr = cpu_to_be64(ioarcb_addr);
+       memcpy(&(ioarcb->cdb[2]), &ioarcb_addr, sizeof(ioarcb_addr));
+}
+
+/**
+ * pmcraid_cancel_hcam - sends ABORT task to abort a given HCAM
+ *
+ * @cmd: command to be used as cancelling command
+ * @type: HCAM type
+ * @cmd_done: op done function for the cancelling command
+ */
+static void pmcraid_cancel_hcam(
+       struct pmcraid_cmd *cmd,
+       u8 type,
+       void (*cmd_done) (struct pmcraid_cmd *)
+)
+{
+       struct pmcraid_instance *pinstance;
+       struct pmcraid_hostrcb  *hcam;
+
+       pinstance = cmd->drv_inst;
+       hcam =  (type == PMCRAID_HCAM_CODE_LOG_DATA) ?
+               &pinstance->ldn : &pinstance->ccn;
+
+       /* prepare for cancelling previous hcam command. If the HCAM is
+        * currently not pending with IOA, we would have hcam->cmd as non-null
+        */
+       if (hcam->cmd == NULL)
+               return;
+
+       pmcraid_prepare_cancel_cmd(cmd, hcam->cmd);
+
+       /* writing to IOARRIN must be protected by host_lock, as mid-layer
+        * schedule queuecommand while we are doing this
+        */
+       pmcraid_send_cmd(cmd, cmd_done,
+                        PMCRAID_INTERNAL_TIMEOUT,
+                        pmcraid_timeout_handler);
+}
+
+/**
+ * pmcraid_cancel_ccn - cancel CCN HCAM already registered with IOA
+ *
+ * @cmd: command block to be used for cancelling the HCAM
+ */
+static void pmcraid_cancel_ccn(struct pmcraid_cmd *cmd)
+{
+       pmcraid_info("response for Cancel LDN CDB[0] = %x ioasc = %x\n",
+                    cmd->ioa_cb->ioarcb.cdb[0],
+                    le32_to_cpu(cmd->ioa_cb->ioasa.ioasc));
+
+       pmcraid_reinit_cmdblk(cmd);
+
+       pmcraid_cancel_hcam(cmd,
+                           PMCRAID_HCAM_CODE_CONFIG_CHANGE,
+                           pmcraid_ioa_shutdown);
+}
+
+/**
+ * pmcraid_cancel_ldn - cancel LDN HCAM already registered with IOA
+ *
+ * @cmd: command block to be used for cancelling the HCAM
+ */
+static void pmcraid_cancel_ldn(struct pmcraid_cmd *cmd)
+{
+       pmcraid_cancel_hcam(cmd,
+                           PMCRAID_HCAM_CODE_LOG_DATA,
+                           pmcraid_cancel_ccn);
+}
+
+/**
+ * pmcraid_expose_resource - check if the resource can be exposed to OS
+ *
+ * @fw_version: firmware version code
+ * @cfgte: pointer to configuration table entry of the resource
+ *
+ * Return value:
+ *     true if resource can be added to midlayer, false(0) otherwise
+ */
+static int pmcraid_expose_resource(u16 fw_version,
+                                  struct pmcraid_config_table_entry *cfgte)
+{
+       int retval = 0;
+
+       if (cfgte->resource_type == RES_TYPE_VSET) {
+               if (fw_version <= PMCRAID_FW_VERSION_1)
+                       retval = ((cfgte->unique_flags1 & 0x80) == 0);
+               else
+                       retval = ((cfgte->unique_flags0 & 0x80) == 0 &&
+                                 (cfgte->unique_flags1 & 0x80) == 0);
+
+       } else if (cfgte->resource_type == RES_TYPE_GSCSI)
+               retval = (RES_BUS(cfgte->resource_address) !=
+                               PMCRAID_VIRTUAL_ENCL_BUS_ID);
+       return retval;
+}
+
+/* attributes supported by pmcraid_event_family */
+enum {
+       PMCRAID_AEN_ATTR_UNSPEC,
+       PMCRAID_AEN_ATTR_EVENT,
+       __PMCRAID_AEN_ATTR_MAX,
+};
+#define PMCRAID_AEN_ATTR_MAX (__PMCRAID_AEN_ATTR_MAX - 1)
+
+/* commands supported by pmcraid_event_family */
+enum {
+       PMCRAID_AEN_CMD_UNSPEC,
+       PMCRAID_AEN_CMD_EVENT,
+       __PMCRAID_AEN_CMD_MAX,
+};
+#define PMCRAID_AEN_CMD_MAX (__PMCRAID_AEN_CMD_MAX - 1)
+
+static struct genl_multicast_group pmcraid_mcgrps[] = {
+       { .name = "events", /* not really used - see ID discussion below */ },
+};
+
+static struct genl_family pmcraid_event_family = {
+       /*
+        * Due to prior multicast group abuse (the code having assumed that
+        * the family ID can be used as a multicast group ID) we need to
+        * statically allocate a family (and thus group) ID.
+        */
+       .id = GENL_ID_PMCRAID,
+       .name = "pmcraid",
+       .version = 1,
+       .maxattr = PMCRAID_AEN_ATTR_MAX,
+       .mcgrps = pmcraid_mcgrps,
+       .n_mcgrps = ARRAY_SIZE(pmcraid_mcgrps),
+};
+
+/**
+ * pmcraid_netlink_init - registers pmcraid_event_family
+ *
+ * Return value:
+ *     0 if the pmcraid_event_family is successfully registered
+ *     with netlink generic, non-zero otherwise
+ */
+static int pmcraid_netlink_init(void)
+{
+       int result;
+
+       result = genl_register_family(&pmcraid_event_family);
+
+       if (result)
+               return result;
+
+       pmcraid_info("registered NETLINK GENERIC group: %d\n",
+                    pmcraid_event_family.id);
+
+       return result;
+}
+
+/**
+ * pmcraid_netlink_release - unregisters pmcraid_event_family
+ *
+ * Return value:
+ *     none
+ */
+static void pmcraid_netlink_release(void)
+{
+       genl_unregister_family(&pmcraid_event_family);
+}
+
+/**
+ * pmcraid_notify_aen - sends event msg to user space application
+ * @pinstance: pointer to adapter instance structure
+ * @type: HCAM type
+ *
+ * Return value:
+ *     0 if success, error value in case of any failure.
+ */
+static int pmcraid_notify_aen(
+       struct pmcraid_instance *pinstance,
+       struct pmcraid_aen_msg  *aen_msg,
+       u32    data_size
+)
+{
+       struct sk_buff *skb;
+       void *msg_header;
+       u32  total_size, nla_genl_hdr_total_size;
+       int result;
+
+       aen_msg->hostno = (pinstance->host->unique_id << 16 |
+                          MINOR(pinstance->cdev.dev));
+       aen_msg->length = data_size;
+
+       data_size += sizeof(*aen_msg);
+
+       total_size = nla_total_size(data_size);
+       /* Add GENL_HDR to total_size */
+       nla_genl_hdr_total_size =
+               (total_size + (GENL_HDRLEN +
+               ((struct genl_family *)&pmcraid_event_family)->hdrsize)
+                + NLMSG_HDRLEN);
+       skb = genlmsg_new(nla_genl_hdr_total_size, GFP_ATOMIC);
+
+
+       if (!skb) {
+               pmcraid_err("Failed to allocate aen data SKB of size: %x\n",
+                            total_size);
+               return -ENOMEM;
+       }
+
+       /* add the genetlink message header */
+       msg_header = genlmsg_put(skb, 0, 0,
+                                &pmcraid_event_family, 0,
+                                PMCRAID_AEN_CMD_EVENT);
+       if (!msg_header) {
+               pmcraid_err("failed to copy command details\n");
+               nlmsg_free(skb);
+               return -ENOMEM;
+       }
+
+       result = nla_put(skb, PMCRAID_AEN_ATTR_EVENT, data_size, aen_msg);
+
+       if (result) {
+               pmcraid_err("failed to copy AEN attribute data\n");
+               nlmsg_free(skb);
+               return -EINVAL;
+       }
+
+       /* send genetlink multicast message to notify appplications */
+       genlmsg_end(skb, msg_header);
+
+       result = genlmsg_multicast(&pmcraid_event_family, skb,
+                                  0, 0, GFP_ATOMIC);
+
+       /* If there are no listeners, genlmsg_multicast may return non-zero
+        * value.
+        */
+       if (result)
+               pmcraid_info("error (%x) sending aen event message\n", result);
+       return result;
+}
+
+/**
+ * pmcraid_notify_ccn - notifies about CCN event msg to user space
+ * @pinstance: pointer adapter instance structure
+ *
+ * Return value:
+ *     0 if success, error value in case of any failure
+ */
+static int pmcraid_notify_ccn(struct pmcraid_instance *pinstance)
+{
+       return pmcraid_notify_aen(pinstance,
+                               pinstance->ccn.msg,
+                               pinstance->ccn.hcam->data_len +
+                               sizeof(struct pmcraid_hcam_hdr));
+}
+
+/**
+ * pmcraid_notify_ldn - notifies about CCN event msg to user space
+ * @pinstance: pointer adapter instance structure
+ *
+ * Return value:
+ *     0 if success, error value in case of any failure
+ */
+static int pmcraid_notify_ldn(struct pmcraid_instance *pinstance)
+{
+       return pmcraid_notify_aen(pinstance,
+                               pinstance->ldn.msg,
+                               pinstance->ldn.hcam->data_len +
+                               sizeof(struct pmcraid_hcam_hdr));
+}
+
+/**
+ * pmcraid_notify_ioastate - sends IOA state event msg to user space
+ * @pinstance: pointer adapter instance structure
+ * @evt: controller state event to be sent
+ *
+ * Return value:
+ *     0 if success, error value in case of any failure
+ */
+static void pmcraid_notify_ioastate(struct pmcraid_instance *pinstance, u32 evt)
+{
+       pinstance->scn.ioa_state = evt;
+       pmcraid_notify_aen(pinstance,
+                         &pinstance->scn.msg,
+                         sizeof(u32));
+}
+
+/**
+ * pmcraid_handle_config_change - Handle a config change from the adapter
+ * @pinstance: pointer to per adapter instance structure
+ *
+ * Return value:
+ *  none
+ */
+
+static void pmcraid_handle_config_change(struct pmcraid_instance *pinstance)
+{
+       struct pmcraid_config_table_entry *cfg_entry;
+       struct pmcraid_hcam_ccn *ccn_hcam;
+       struct pmcraid_cmd *cmd;
+       struct pmcraid_cmd *cfgcmd;
+       struct pmcraid_resource_entry *res = NULL;
+       unsigned long lock_flags;
+       unsigned long host_lock_flags;
+       u32 new_entry = 1;
+       u32 hidden_entry = 0;
+       u16 fw_version;
+       int rc;
+
+       ccn_hcam = (struct pmcraid_hcam_ccn *)pinstance->ccn.hcam;
+       cfg_entry = &ccn_hcam->cfg_entry;
+       fw_version = be16_to_cpu(pinstance->inq_data->fw_version);
+
+       pmcraid_info("CCN(%x): %x timestamp: %llx type: %x lost: %x flags: %x \
+                res: %x:%x:%x:%x\n",
+                pinstance->ccn.hcam->ilid,
+                pinstance->ccn.hcam->op_code,
+               ((pinstance->ccn.hcam->timestamp1) |
+               ((pinstance->ccn.hcam->timestamp2 & 0xffffffffLL) << 32)),
+                pinstance->ccn.hcam->notification_type,
+                pinstance->ccn.hcam->notification_lost,
+                pinstance->ccn.hcam->flags,
+                pinstance->host->unique_id,
+                RES_IS_VSET(*cfg_entry) ? PMCRAID_VSET_BUS_ID :
+                (RES_IS_GSCSI(*cfg_entry) ? PMCRAID_PHYS_BUS_ID :
+                       RES_BUS(cfg_entry->resource_address)),
+                RES_IS_VSET(*cfg_entry) ?
+                       (fw_version <= PMCRAID_FW_VERSION_1 ?
+                               cfg_entry->unique_flags1 :
+                                       cfg_entry->array_id & 0xFF) :
+                       RES_TARGET(cfg_entry->resource_address),
+                RES_LUN(cfg_entry->resource_address));
+
+
+       /* If this HCAM indicates a lost notification, read the config table */
+       if (pinstance->ccn.hcam->notification_lost) {
+               cfgcmd = pmcraid_get_free_cmd(pinstance);
+               if (cfgcmd) {
+                       pmcraid_info("lost CCN, reading config table\b");
+                       pinstance->reinit_cfg_table = 1;
+                       pmcraid_querycfg(cfgcmd);
+               } else {
+                       pmcraid_err("lost CCN, no free cmd for querycfg\n");
+               }
+               goto out_notify_apps;
+       }
+
+       /* If this resource is not going to be added to mid-layer, just notify
+        * applications and return. If this notification is about hiding a VSET
+        * resource, check if it was exposed already.
+        */
+       if (pinstance->ccn.hcam->notification_type ==
+           NOTIFICATION_TYPE_ENTRY_CHANGED &&
+           cfg_entry->resource_type == RES_TYPE_VSET) {
+
+               if (fw_version <= PMCRAID_FW_VERSION_1)
+                       hidden_entry = (cfg_entry->unique_flags1 & 0x80) != 0;
+               else
+                       hidden_entry = (cfg_entry->unique_flags1 & 0x80) != 0;
+
+       } else if (!pmcraid_expose_resource(fw_version, cfg_entry)) {
+               goto out_notify_apps;
+       }
+
+       spin_lock_irqsave(&pinstance->resource_lock, lock_flags);
+       list_for_each_entry(res, &pinstance->used_res_q, queue) {
+               rc = memcmp(&res->cfg_entry.resource_address,
+                           &cfg_entry->resource_address,
+                           sizeof(cfg_entry->resource_address));
+               if (!rc) {
+                       new_entry = 0;
+                       break;
+               }
+       }
+
+       if (new_entry) {
+
+               if (hidden_entry) {
+                       spin_unlock_irqrestore(&pinstance->resource_lock,
+                                               lock_flags);
+                       goto out_notify_apps;
+               }
+
+               /* If there are more number of resources than what driver can
+                * manage, do not notify the applications about the CCN. Just
+                * ignore this notifications and re-register the same HCAM
+                */
+               if (list_empty(&pinstance->free_res_q)) {
+                       spin_unlock_irqrestore(&pinstance->resource_lock,
+                                               lock_flags);
+                       pmcraid_err("too many resources attached\n");
+                       spin_lock_irqsave(pinstance->host->host_lock,
+                                         host_lock_flags);
+                       pmcraid_send_hcam(pinstance,
+                                         PMCRAID_HCAM_CODE_CONFIG_CHANGE);
+                       spin_unlock_irqrestore(pinstance->host->host_lock,
+                                              host_lock_flags);
+                       return;
+               }
+
+               res = list_entry(pinstance->free_res_q.next,
+                                struct pmcraid_resource_entry, queue);
+
+               list_del(&res->queue);
+               res->scsi_dev = NULL;
+               res->reset_progress = 0;
+               list_add_tail(&res->queue, &pinstance->used_res_q);
+       }
+
+       memcpy(&res->cfg_entry, cfg_entry, pinstance->config_table_entry_size);
+
+       if (pinstance->ccn.hcam->notification_type ==
+           NOTIFICATION_TYPE_ENTRY_DELETED || hidden_entry) {
+               if (res->scsi_dev) {
+                       if (fw_version <= PMCRAID_FW_VERSION_1)
+                               res->cfg_entry.unique_flags1 &= 0x7F;
+                       else
+                               res->cfg_entry.array_id &= 0xFF;
+                       res->change_detected = RES_CHANGE_DEL;
+                       res->cfg_entry.resource_handle =
+                               PMCRAID_INVALID_RES_HANDLE;
+                       schedule_work(&pinstance->worker_q);
+               } else {
+                       /* This may be one of the non-exposed resources */
+                       list_move_tail(&res->queue, &pinstance->free_res_q);
+               }
+       } else if (!res->scsi_dev) {
+               res->change_detected = RES_CHANGE_ADD;
+               schedule_work(&pinstance->worker_q);
+       }
+       spin_unlock_irqrestore(&pinstance->resource_lock, lock_flags);
+
+out_notify_apps:
+
+       /* Notify configuration changes to registered applications.*/
+       if (!pmcraid_disable_aen)
+               pmcraid_notify_ccn(pinstance);
+
+       cmd = pmcraid_init_hcam(pinstance, PMCRAID_HCAM_CODE_CONFIG_CHANGE);
+       if (cmd)
+               pmcraid_send_hcam_cmd(cmd);
+}
+
+/**
+ * pmcraid_get_error_info - return error string for an ioasc
+ * @ioasc: ioasc code
+ * Return Value
+ *      none
+ */
+static struct pmcraid_ioasc_error *pmcraid_get_error_info(u32 ioasc)
+{
+       int i;
+       for (i = 0; i < ARRAY_SIZE(pmcraid_ioasc_error_table); i++) {
+               if (pmcraid_ioasc_error_table[i].ioasc_code == ioasc)
+                       return &pmcraid_ioasc_error_table[i];
+       }
+       return NULL;
+}
+
+/**
+ * pmcraid_ioasc_logger - log IOASC information based user-settings
+ * @ioasc: ioasc code
+ * @cmd: pointer to command that resulted in 'ioasc'
+ */
+void pmcraid_ioasc_logger(u32 ioasc, struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_ioasc_error *error_info = pmcraid_get_error_info(ioasc);
+
+       if (error_info == NULL ||
+               cmd->drv_inst->current_log_level < error_info->log_level)
+               return;
+
+       /* log the error string */
+       pmcraid_err("cmd [%x] for resource %x failed with %x(%s)\n",
+               cmd->ioa_cb->ioarcb.cdb[0],
+               cmd->ioa_cb->ioarcb.resource_handle,
+               le32_to_cpu(ioasc), error_info->error_string);
+}
+
+/**
+ * pmcraid_handle_error_log - Handle a config change (error log) from the IOA
+ *
+ * @pinstance: pointer to per adapter instance structure
+ *
+ * Return value:
+ *  none
+ */
+static void pmcraid_handle_error_log(struct pmcraid_instance *pinstance)
+{
+       struct pmcraid_hcam_ldn *hcam_ldn;
+       u32 ioasc;
+
+       hcam_ldn = (struct pmcraid_hcam_ldn *)pinstance->ldn.hcam;
+
+       pmcraid_info
+               ("LDN(%x): %x type: %x lost: %x flags: %x overlay id: %x\n",
+                pinstance->ldn.hcam->ilid,
+                pinstance->ldn.hcam->op_code,
+                pinstance->ldn.hcam->notification_type,
+                pinstance->ldn.hcam->notification_lost,
+                pinstance->ldn.hcam->flags,
+                pinstance->ldn.hcam->overlay_id);
+
+       /* log only the errors, no need to log informational log entries */
+       if (pinstance->ldn.hcam->notification_type !=
+           NOTIFICATION_TYPE_ERROR_LOG)
+               return;
+
+       if (pinstance->ldn.hcam->notification_lost ==
+           HOSTRCB_NOTIFICATIONS_LOST)
+               dev_info(&pinstance->pdev->dev, "Error notifications lost\n");
+
+       ioasc = le32_to_cpu(hcam_ldn->error_log.fd_ioasc);
+
+       if (ioasc == PMCRAID_IOASC_UA_BUS_WAS_RESET ||
+               ioasc == PMCRAID_IOASC_UA_BUS_WAS_RESET_BY_OTHER) {
+               dev_info(&pinstance->pdev->dev,
+                       "UnitAttention due to IOA Bus Reset\n");
+               scsi_report_bus_reset(
+                       pinstance->host,
+                       RES_BUS(hcam_ldn->error_log.fd_ra));
+       }
+
+       return;
+}
+
+/**
+ * pmcraid_process_ccn - Op done function for a CCN.
+ * @cmd: pointer to command struct
+ *
+ * This function is the op done function for a configuration
+ * change notification
+ *
+ * Return value:
+ * none
+ */
+static void pmcraid_process_ccn(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       u32 ioasc = le32_to_cpu(cmd->ioa_cb->ioasa.ioasc);
+       unsigned long lock_flags;
+
+       pinstance->ccn.cmd = NULL;
+       pmcraid_return_cmd(cmd);
+
+       /* If driver initiated IOA reset happened while this hcam was pending
+        * with IOA, or IOA bringdown sequence is in progress, no need to
+        * re-register the hcam
+        */
+       if (ioasc == PMCRAID_IOASC_IOA_WAS_RESET ||
+           atomic_read(&pinstance->ccn.ignore) == 1) {
+               return;
+       } else if (ioasc) {
+               dev_info(&pinstance->pdev->dev,
+                       "Host RCB (CCN) failed with IOASC: 0x%08X\n", ioasc);
+               spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+               pmcraid_send_hcam(pinstance, PMCRAID_HCAM_CODE_CONFIG_CHANGE);
+               spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+       } else {
+               pmcraid_handle_config_change(pinstance);
+       }
+}
+
+/**
+ * pmcraid_process_ldn - op done function for an LDN
+ * @cmd: pointer to command block
+ *
+ * Return value
+ *   none
+ */
+static void pmcraid_initiate_reset(struct pmcraid_instance *);
+static void pmcraid_set_timestamp(struct pmcraid_cmd *cmd);
+
+static void pmcraid_process_ldn(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       struct pmcraid_hcam_ldn *ldn_hcam =
+                       (struct pmcraid_hcam_ldn *)pinstance->ldn.hcam;
+       u32 ioasc = le32_to_cpu(cmd->ioa_cb->ioasa.ioasc);
+       u32 fd_ioasc = le32_to_cpu(ldn_hcam->error_log.fd_ioasc);
+       unsigned long lock_flags;
+
+       /* return the command block back to freepool */
+       pinstance->ldn.cmd = NULL;
+       pmcraid_return_cmd(cmd);
+
+       /* If driver initiated IOA reset happened while this hcam was pending
+        * with IOA, no need to re-register the hcam as reset engine will do it
+        * once reset sequence is complete
+        */
+       if (ioasc == PMCRAID_IOASC_IOA_WAS_RESET ||
+           atomic_read(&pinstance->ccn.ignore) == 1) {
+               return;
+       } else if (!ioasc) {
+               pmcraid_handle_error_log(pinstance);
+               if (fd_ioasc == PMCRAID_IOASC_NR_IOA_RESET_REQUIRED) {
+                       spin_lock_irqsave(pinstance->host->host_lock,
+                                         lock_flags);
+                       pmcraid_initiate_reset(pinstance);
+                       spin_unlock_irqrestore(pinstance->host->host_lock,
+                                              lock_flags);
+                       return;
+               }
+               if (fd_ioasc == PMCRAID_IOASC_TIME_STAMP_OUT_OF_SYNC) {
+                       pinstance->timestamp_error = 1;
+                       pmcraid_set_timestamp(cmd);
+               }
+       } else {
+               dev_info(&pinstance->pdev->dev,
+                       "Host RCB(LDN) failed with IOASC: 0x%08X\n", ioasc);
+       }
+       /* send netlink message for HCAM notification if enabled */
+       if (!pmcraid_disable_aen)
+               pmcraid_notify_ldn(pinstance);
+
+       cmd = pmcraid_init_hcam(pinstance, PMCRAID_HCAM_CODE_LOG_DATA);
+       if (cmd)
+               pmcraid_send_hcam_cmd(cmd);
+}
+
+/**
+ * pmcraid_register_hcams - register HCAMs for CCN and LDN
+ *
+ * @pinstance: pointer per adapter instance structure
+ *
+ * Return Value
+ *   none
+ */
+static void pmcraid_register_hcams(struct pmcraid_instance *pinstance)
+{
+       pmcraid_send_hcam(pinstance, PMCRAID_HCAM_CODE_CONFIG_CHANGE);
+       pmcraid_send_hcam(pinstance, PMCRAID_HCAM_CODE_LOG_DATA);
+}
+
+/**
+ * pmcraid_unregister_hcams - cancel HCAMs registered already
+ * @cmd: pointer to command used as part of reset sequence
+ */
+static void pmcraid_unregister_hcams(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+
+       /* During IOA bringdown, HCAM gets fired and tasklet proceeds with
+        * handling hcam response though it is not necessary. In order to
+        * prevent this, set 'ignore', so that bring-down sequence doesn't
+        * re-send any more hcams
+        */
+       atomic_set(&pinstance->ccn.ignore, 1);
+       atomic_set(&pinstance->ldn.ignore, 1);
+
+       /* If adapter reset was forced as part of runtime reset sequence,
+        * start the reset sequence. Reset will be triggered even in case
+        * IOA unit_check.
+        */
+       if ((pinstance->force_ioa_reset && !pinstance->ioa_bringdown) ||
+            pinstance->ioa_unit_check) {
+               pinstance->force_ioa_reset = 0;
+               pinstance->ioa_unit_check = 0;
+               pinstance->ioa_state = IOA_STATE_IN_RESET_ALERT;
+               pmcraid_reset_alert(cmd);
+               return;
+       }
+
+       /* Driver tries to cancel HCAMs by sending ABORT TASK for each HCAM
+        * one after the other. So CCN cancellation will be triggered by
+        * pmcraid_cancel_ldn itself.
+        */
+       pmcraid_cancel_ldn(cmd);
+}
+
+/**
+ * pmcraid_reset_enable_ioa - re-enable IOA after a hard reset
+ * @pinstance: pointer to adapter instance structure
+ * Return Value
+ *  1 if TRANSITION_TO_OPERATIONAL is active, otherwise 0
+ */
+static void pmcraid_reinit_buffers(struct pmcraid_instance *);
+
+static int pmcraid_reset_enable_ioa(struct pmcraid_instance *pinstance)
+{
+       u32 intrs;
+
+       pmcraid_reinit_buffers(pinstance);
+       intrs = pmcraid_read_interrupts(pinstance);
+
+       pmcraid_enable_interrupts(pinstance, PMCRAID_PCI_INTERRUPTS);
+
+       if (intrs & INTRS_TRANSITION_TO_OPERATIONAL) {
+               if (!pinstance->interrupt_mode) {
+                       iowrite32(INTRS_TRANSITION_TO_OPERATIONAL,
+                               pinstance->int_regs.
+                               ioa_host_interrupt_mask_reg);
+                       iowrite32(INTRS_TRANSITION_TO_OPERATIONAL,
+                               pinstance->int_regs.ioa_host_interrupt_clr_reg);
+               }
+               return 1;
+       } else {
+               return 0;
+       }
+}
+
+/**
+ * pmcraid_soft_reset - performs a soft reset and makes IOA become ready
+ * @cmd : pointer to reset command block
+ *
+ * Return Value
+ *     none
+ */
+static void pmcraid_soft_reset(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       u32 int_reg;
+       u32 doorbell;
+
+       /* There will be an interrupt when Transition to Operational bit is
+        * set so tasklet would execute next reset task. The timeout handler
+        * would re-initiate a reset
+        */
+       cmd->cmd_done = pmcraid_ioa_reset;
+       cmd->timer.data = (unsigned long)cmd;
+       cmd->timer.expires = jiffies +
+                            msecs_to_jiffies(PMCRAID_TRANSOP_TIMEOUT);
+       cmd->timer.function = (void (*)(unsigned long))pmcraid_timeout_handler;
+
+       if (!timer_pending(&cmd->timer))
+               add_timer(&cmd->timer);
+
+       /* Enable destructive diagnostics on IOA if it is not yet in
+        * operational state
+        */
+       doorbell = DOORBELL_RUNTIME_RESET |
+                  DOORBELL_ENABLE_DESTRUCTIVE_DIAGS;
+
+       /* Since we do RESET_ALERT and Start BIST we have to again write
+        * MSIX Doorbell to indicate the interrupt mode
+        */
+       if (pinstance->interrupt_mode) {
+               iowrite32(DOORBELL_INTR_MODE_MSIX,
+                         pinstance->int_regs.host_ioa_interrupt_reg);
+               ioread32(pinstance->int_regs.host_ioa_interrupt_reg);
+       }
+
+       iowrite32(doorbell, pinstance->int_regs.host_ioa_interrupt_reg);
+       ioread32(pinstance->int_regs.host_ioa_interrupt_reg),
+       int_reg = ioread32(pinstance->int_regs.ioa_host_interrupt_reg);
+
+       pmcraid_info("Waiting for IOA to become operational %x:%x\n",
+                    ioread32(pinstance->int_regs.host_ioa_interrupt_reg),
+                    int_reg);
+}
+
+/**
+ * pmcraid_get_dump - retrieves IOA dump in case of Unit Check interrupt
+ *
+ * @pinstance: pointer to adapter instance structure
+ *
+ * Return Value
+ *     none
+ */
+static void pmcraid_get_dump(struct pmcraid_instance *pinstance)
+{
+       pmcraid_info("%s is not yet implemented\n", __func__);
+}
+
+/**
+ * pmcraid_fail_outstanding_cmds - Fails all outstanding ops.
+ * @pinstance: pointer to adapter instance structure
+ *
+ * This function fails all outstanding ops. If they are submitted to IOA
+ * already, it sends cancel all messages if IOA is still accepting IOARCBs,
+ * otherwise just completes the commands and returns the cmd blocks to free
+ * pool.
+ *
+ * Return value:
+ *      none
+ */
+static void pmcraid_fail_outstanding_cmds(struct pmcraid_instance *pinstance)
+{
+       struct pmcraid_cmd *cmd, *temp;
+       unsigned long lock_flags;
+
+       /* pending command list is protected by pending_pool_lock. Its
+        * traversal must be done as within this lock
+        */
+       spin_lock_irqsave(&pinstance->pending_pool_lock, lock_flags);
+       list_for_each_entry_safe(cmd, temp, &pinstance->pending_cmd_pool,
+                                free_list) {
+               list_del(&cmd->free_list);
+               spin_unlock_irqrestore(&pinstance->pending_pool_lock,
+                                       lock_flags);
+               cmd->ioa_cb->ioasa.ioasc =
+                       cpu_to_le32(PMCRAID_IOASC_IOA_WAS_RESET);
+               cmd->ioa_cb->ioasa.ilid =
+                       cpu_to_be32(PMCRAID_DRIVER_ILID);
+
+               /* In case the command timer is still running */
+               del_timer(&cmd->timer);
+
+               /* If this is an IO command, complete it by invoking scsi_done
+                * function. If this is one of the internal commands other
+                * than pmcraid_ioa_reset and HCAM commands invoke cmd_done to
+                * complete it
+                */
+               if (cmd->scsi_cmd) {
+
+                       struct scsi_cmnd *scsi_cmd = cmd->scsi_cmd;
+                       __le32 resp = cmd->ioa_cb->ioarcb.response_handle;
+
+                       scsi_cmd->result |= DID_ERROR << 16;
+
+                       scsi_dma_unmap(scsi_cmd);
+                       pmcraid_return_cmd(cmd);
+
+                       pmcraid_info("failing(%d) CDB[0] = %x result: %x\n",
+                                    le32_to_cpu(resp) >> 2,
+                                    cmd->ioa_cb->ioarcb.cdb[0],
+                                    scsi_cmd->result);
+                       scsi_cmd->scsi_done(scsi_cmd);
+               } else if (cmd->cmd_done == pmcraid_internal_done ||
+                          cmd->cmd_done == pmcraid_erp_done) {
+                       cmd->cmd_done(cmd);
+               } else if (cmd->cmd_done != pmcraid_ioa_reset &&
+                          cmd->cmd_done != pmcraid_ioa_shutdown_done) {
+                       pmcraid_return_cmd(cmd);
+               }
+
+               atomic_dec(&pinstance->outstanding_cmds);
+               spin_lock_irqsave(&pinstance->pending_pool_lock, lock_flags);
+       }
+
+       spin_unlock_irqrestore(&pinstance->pending_pool_lock, lock_flags);
+}
+
+/**
+ * pmcraid_ioa_reset - Implementation of IOA reset logic
+ *
+ * @cmd: pointer to the cmd block to be used for entire reset process
+ *
+ * This function executes most of the steps required for IOA reset. This gets
+ * called by user threads (modprobe/insmod/rmmod) timer, tasklet and midlayer's
+ * 'eh_' thread. Access to variables used for controlling the reset sequence is
+ * synchronized using host lock. Various functions called during reset process
+ * would make use of a single command block, pointer to which is also stored in
+ * adapter instance structure.
+ *
+ * Return Value
+ *      None
+ */
+static void pmcraid_ioa_reset(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       u8 reset_complete = 0;
+
+       pinstance->ioa_reset_in_progress = 1;
+
+       if (pinstance->reset_cmd != cmd) {
+               pmcraid_err("reset is called with different command block\n");
+               pinstance->reset_cmd = cmd;
+       }
+
+       pmcraid_info("reset_engine: state = %d, command = %p\n",
+                     pinstance->ioa_state, cmd);
+
+       switch (pinstance->ioa_state) {
+
+       case IOA_STATE_DEAD:
+               /* If IOA is offline, whatever may be the reset reason, just
+                * return. callers might be waiting on the reset wait_q, wake
+                * up them
+                */
+               pmcraid_err("IOA is offline no reset is possible\n");
+               reset_complete = 1;
+               break;
+
+       case IOA_STATE_IN_BRINGDOWN:
+               /* we enter here, once ioa shutdown command is processed by IOA
+                * Alert IOA for a possible reset. If reset alert fails, IOA
+                * goes through hard-reset
+                */
+               pmcraid_disable_interrupts(pinstance, ~0);
+               pinstance->ioa_state = IOA_STATE_IN_RESET_ALERT;
+               pmcraid_reset_alert(cmd);
+               break;
+
+       case IOA_STATE_UNKNOWN:
+               /* We may be called during probe or resume. Some pre-processing
+                * is required for prior to reset
+                */
+               scsi_block_requests(pinstance->host);
+
+               /* If asked to reset while IOA was processing responses or
+                * there are any error responses then IOA may require
+                * hard-reset.
+                */
+               if (pinstance->ioa_hard_reset == 0) {
+                       if (ioread32(pinstance->ioa_status) &
+                           INTRS_TRANSITION_TO_OPERATIONAL) {
+                               pmcraid_info("sticky bit set, bring-up\n");
+                               pinstance->ioa_state = IOA_STATE_IN_BRINGUP;
+                               pmcraid_reinit_cmdblk(cmd);
+                               pmcraid_identify_hrrq(cmd);
+                       } else {
+                               pinstance->ioa_state = IOA_STATE_IN_SOFT_RESET;
+                               pmcraid_soft_reset(cmd);
+                       }
+               } else {
+                       /* Alert IOA of a possible reset and wait for critical
+                        * operation in progress bit to reset
+                        */
+                       pinstance->ioa_state = IOA_STATE_IN_RESET_ALERT;
+                       pmcraid_reset_alert(cmd);
+               }
+               break;
+
+       case IOA_STATE_IN_RESET_ALERT:
+               /* If critical operation in progress bit is reset or wait gets
+                * timed out, reset proceeds with starting BIST on the IOA.
+                * pmcraid_ioa_hard_reset keeps a count of reset attempts. If
+                * they are 3 or more, reset engine marks IOA dead and returns
+                */
+               pinstance->ioa_state = IOA_STATE_IN_HARD_RESET;
+               pmcraid_start_bist(cmd);
+               break;
+
+       case IOA_STATE_IN_HARD_RESET:
+               pinstance->ioa_reset_attempts++;
+
+               /* retry reset if we haven't reached maximum allowed limit */
+               if (pinstance->ioa_reset_attempts > PMCRAID_RESET_ATTEMPTS) {
+                       pinstance->ioa_reset_attempts = 0;
+                       pmcraid_err("IOA didn't respond marking it as dead\n");
+                       pinstance->ioa_state = IOA_STATE_DEAD;
+
+                       if (pinstance->ioa_bringdown)
+                               pmcraid_notify_ioastate(pinstance,
+                                       PMC_DEVICE_EVENT_SHUTDOWN_FAILED);
+                       else
+                               pmcraid_notify_ioastate(pinstance,
+                                               PMC_DEVICE_EVENT_RESET_FAILED);
+                       reset_complete = 1;
+                       break;
+               }
+
+               /* Once either bist or pci reset is done, restore PCI config
+                * space. If this fails, proceed with hard reset again
+                */
+               pci_restore_state(pinstance->pdev);
+
+               /* fail all pending commands */
+               pmcraid_fail_outstanding_cmds(pinstance);
+
+               /* check if unit check is active, if so extract dump */
+               if (pinstance->ioa_unit_check) {
+                       pmcraid_info("unit check is active\n");
+                       pinstance->ioa_unit_check = 0;
+                       pmcraid_get_dump(pinstance);
+                       pinstance->ioa_reset_attempts--;
+                       pinstance->ioa_state = IOA_STATE_IN_RESET_ALERT;
+                       pmcraid_reset_alert(cmd);
+                       break;
+               }
+
+               /* if the reset reason is to bring-down the ioa, we might be
+                * done with the reset restore pci_config_space and complete
+                * the reset
+                */
+               if (pinstance->ioa_bringdown) {
+                       pmcraid_info("bringing down the adapter\n");
+                       pinstance->ioa_shutdown_type = SHUTDOWN_NONE;
+                       pinstance->ioa_bringdown = 0;
+                       pinstance->ioa_state = IOA_STATE_UNKNOWN;
+                       pmcraid_notify_ioastate(pinstance,
+                                       PMC_DEVICE_EVENT_SHUTDOWN_SUCCESS);
+                       reset_complete = 1;
+               } else {
+                       /* bring-up IOA, so proceed with soft reset
+                        * Reinitialize hrrq_buffers and their indices also
+                        * enable interrupts after a pci_restore_state
+                        */
+                       if (pmcraid_reset_enable_ioa(pinstance)) {
+                               pinstance->ioa_state = IOA_STATE_IN_BRINGUP;
+                               pmcraid_info("bringing up the adapter\n");
+                               pmcraid_reinit_cmdblk(cmd);
+                               pmcraid_identify_hrrq(cmd);
+                       } else {
+                               pinstance->ioa_state = IOA_STATE_IN_SOFT_RESET;
+                               pmcraid_soft_reset(cmd);
+                       }
+               }
+               break;
+
+       case IOA_STATE_IN_SOFT_RESET:
+               /* TRANSITION TO OPERATIONAL is on so start initialization
+                * sequence
+                */
+               pmcraid_info("In softreset proceeding with bring-up\n");
+               pinstance->ioa_state = IOA_STATE_IN_BRINGUP;
+
+               /* Initialization commands start with HRRQ identification. From
+                * now on tasklet completes most of the commands as IOA is up
+                * and intrs are enabled
+                */
+               pmcraid_identify_hrrq(cmd);
+               break;
+
+       case IOA_STATE_IN_BRINGUP:
+               /* we are done with bringing up of IOA, change the ioa_state to
+                * operational and wake up any waiters
+                */
+               pinstance->ioa_state = IOA_STATE_OPERATIONAL;
+               reset_complete = 1;
+               break;
+
+       case IOA_STATE_OPERATIONAL:
+       default:
+               /* When IOA is operational and a reset is requested, check for
+                * the reset reason. If reset is to bring down IOA, unregister
+                * HCAMs and initiate shutdown; if adapter reset is forced then
+                * restart reset sequence again
+                */
+               if (pinstance->ioa_shutdown_type == SHUTDOWN_NONE &&
+                   pinstance->force_ioa_reset == 0) {
+                       pmcraid_notify_ioastate(pinstance,
+                                               PMC_DEVICE_EVENT_RESET_SUCCESS);
+                       reset_complete = 1;
+               } else {
+                       if (pinstance->ioa_shutdown_type != SHUTDOWN_NONE)
+                               pinstance->ioa_state = IOA_STATE_IN_BRINGDOWN;
+                       pmcraid_reinit_cmdblk(cmd);
+                       pmcraid_unregister_hcams(cmd);
+               }
+               break;
+       }
+
+       /* reset will be completed if ioa_state is either DEAD or UNKNOWN or
+        * OPERATIONAL. Reset all control variables used during reset, wake up
+        * any waiting threads and let the SCSI mid-layer send commands. Note
+        * that host_lock must be held before invoking scsi_report_bus_reset.
+        */
+       if (reset_complete) {
+               pinstance->ioa_reset_in_progress = 0;
+               pinstance->ioa_reset_attempts = 0;
+               pinstance->reset_cmd = NULL;
+               pinstance->ioa_shutdown_type = SHUTDOWN_NONE;
+               pinstance->ioa_bringdown = 0;
+               pmcraid_return_cmd(cmd);
+
+               /* If target state is to bring up the adapter, proceed with
+                * hcam registration and resource exposure to mid-layer.
+                */
+               if (pinstance->ioa_state == IOA_STATE_OPERATIONAL)
+                       pmcraid_register_hcams(pinstance);
+
+               wake_up_all(&pinstance->reset_wait_q);
+       }
+
+       return;
+}
+
+/**
+ * pmcraid_initiate_reset - initiates reset sequence. This is called from
+ * ISR/tasklet during error interrupts including IOA unit check. If reset
+ * is already in progress, it just returns, otherwise initiates IOA reset
+ * to bring IOA up to operational state.
+ *
+ * @pinstance: pointer to adapter instance structure
+ *
+ * Return value
+ *      none
+ */
+static void pmcraid_initiate_reset(struct pmcraid_instance *pinstance)
+{
+       struct pmcraid_cmd *cmd;
+
+       /* If the reset is already in progress, just return, otherwise start
+        * reset sequence and return
+        */
+       if (!pinstance->ioa_reset_in_progress) {
+               scsi_block_requests(pinstance->host);
+               cmd = pmcraid_get_free_cmd(pinstance);
+
+               if (cmd == NULL) {
+                       pmcraid_err("no cmnd blocks for initiate_reset\n");
+                       return;
+               }
+
+               pinstance->ioa_shutdown_type = SHUTDOWN_NONE;
+               pinstance->reset_cmd = cmd;
+               pinstance->force_ioa_reset = 1;
+               pmcraid_notify_ioastate(pinstance,
+                                       PMC_DEVICE_EVENT_RESET_START);
+               pmcraid_ioa_reset(cmd);
+       }
+}
+
+/**
+ * pmcraid_reset_reload - utility routine for doing IOA reset either to bringup
+ *                       or bringdown IOA
+ * @pinstance: pointer adapter instance structure
+ * @shutdown_type: shutdown type to be used NONE, NORMAL or ABRREV
+ * @target_state: expected target state after reset
+ *
+ * Note: This command initiates reset and waits for its completion. Hence this
+ * should not be called from isr/timer/tasklet functions (timeout handlers,
+ * error response handlers and interrupt handlers).
+ *
+ * Return Value
+ *      1 in case ioa_state is not target_state, 0 otherwise.
+ */
+static int pmcraid_reset_reload(
+       struct pmcraid_instance *pinstance,
+       u8 shutdown_type,
+       u8 target_state
+)
+{
+       struct pmcraid_cmd *reset_cmd = NULL;
+       unsigned long lock_flags;
+       int reset = 1;
+
+       spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+
+       if (pinstance->ioa_reset_in_progress) {
+               pmcraid_info("reset_reload: reset is already in progress\n");
+
+               spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+
+               wait_event(pinstance->reset_wait_q,
+                          !pinstance->ioa_reset_in_progress);
+
+               spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+
+               if (pinstance->ioa_state == IOA_STATE_DEAD) {
+                       spin_unlock_irqrestore(pinstance->host->host_lock,
+                                              lock_flags);
+                       pmcraid_info("reset_reload: IOA is dead\n");
+                       return reset;
+               } else if (pinstance->ioa_state == target_state) {
+                       reset = 0;
+               }
+       }
+
+       if (reset) {
+               pmcraid_info("reset_reload: proceeding with reset\n");
+               scsi_block_requests(pinstance->host);
+               reset_cmd = pmcraid_get_free_cmd(pinstance);
+
+               if (reset_cmd == NULL) {
+                       pmcraid_err("no free cmnd for reset_reload\n");
+                       spin_unlock_irqrestore(pinstance->host->host_lock,
+                                              lock_flags);
+                       return reset;
+               }
+
+               if (shutdown_type == SHUTDOWN_NORMAL)
+                       pinstance->ioa_bringdown = 1;
+
+               pinstance->ioa_shutdown_type = shutdown_type;
+               pinstance->reset_cmd = reset_cmd;
+               pinstance->force_ioa_reset = reset;
+               pmcraid_info("reset_reload: initiating reset\n");
+               pmcraid_ioa_reset(reset_cmd);
+               spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+               pmcraid_info("reset_reload: waiting for reset to complete\n");
+               wait_event(pinstance->reset_wait_q,
+                          !pinstance->ioa_reset_in_progress);
+
+               pmcraid_info("reset_reload: reset is complete !!\n");
+               scsi_unblock_requests(pinstance->host);
+               if (pinstance->ioa_state == target_state)
+                       reset = 0;
+       }
+
+       return reset;
+}
+
+/**
+ * pmcraid_reset_bringdown - wrapper over pmcraid_reset_reload to bringdown IOA
+ *
+ * @pinstance: pointer to adapter instance structure
+ *
+ * Return Value
+ *      whatever is returned from pmcraid_reset_reload
+ */
+static int pmcraid_reset_bringdown(struct pmcraid_instance *pinstance)
+{
+       return pmcraid_reset_reload(pinstance,
+                                   SHUTDOWN_NORMAL,
+                                   IOA_STATE_UNKNOWN);
+}
+
+/**
+ * pmcraid_reset_bringup - wrapper over pmcraid_reset_reload to bring up IOA
+ *
+ * @pinstance: pointer to adapter instance structure
+ *
+ * Return Value
+ *      whatever is returned from pmcraid_reset_reload
+ */
+static int pmcraid_reset_bringup(struct pmcraid_instance *pinstance)
+{
+       pmcraid_notify_ioastate(pinstance, PMC_DEVICE_EVENT_RESET_START);
+
+       return pmcraid_reset_reload(pinstance,
+                                   SHUTDOWN_NONE,
+                                   IOA_STATE_OPERATIONAL);
+}
+
+/**
+ * pmcraid_request_sense - Send request sense to a device
+ * @cmd: pmcraid command struct
+ *
+ * This function sends a request sense to a device as a result of a check
+ * condition. This method re-uses the same command block that failed earlier.
+ */
+static void pmcraid_request_sense(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
+       struct pmcraid_ioadl_desc *ioadl = ioarcb->add_data.u.ioadl;
+
+       /* allocate DMAable memory for sense buffers */
+       cmd->sense_buffer = pci_alloc_consistent(cmd->drv_inst->pdev,
+                                                SCSI_SENSE_BUFFERSIZE,
+                                                &cmd->sense_buffer_dma);
+
+       if (cmd->sense_buffer == NULL) {
+               pmcraid_err
+                       ("couldn't allocate sense buffer for request sense\n");
+               pmcraid_erp_done(cmd);
+               return;
+       }
+
+       /* re-use the command block */
+       memset(&cmd->ioa_cb->ioasa, 0, sizeof(struct pmcraid_ioasa));
+       memset(ioarcb->cdb, 0, PMCRAID_MAX_CDB_LEN);
+       ioarcb->request_flags0 = (SYNC_COMPLETE |
+                                 NO_LINK_DESCS |
+                                 INHIBIT_UL_CHECK);
+       ioarcb->request_type = REQ_TYPE_SCSI;
+       ioarcb->cdb[0] = REQUEST_SENSE;
+       ioarcb->cdb[4] = SCSI_SENSE_BUFFERSIZE;
+
+       ioarcb->ioadl_bus_addr = cpu_to_le64((cmd->ioa_cb_bus_addr) +
+                                       offsetof(struct pmcraid_ioarcb,
+                                               add_data.u.ioadl[0]));
+       ioarcb->ioadl_length = cpu_to_le32(sizeof(struct pmcraid_ioadl_desc));
+
+       ioarcb->data_transfer_length = cpu_to_le32(SCSI_SENSE_BUFFERSIZE);
+
+       ioadl->address = cpu_to_le64(cmd->sense_buffer_dma);
+       ioadl->data_len = cpu_to_le32(SCSI_SENSE_BUFFERSIZE);
+       ioadl->flags = IOADL_FLAGS_LAST_DESC;
+
+       /* request sense might be called as part of error response processing
+        * which runs in tasklets context. It is possible that mid-layer might
+        * schedule queuecommand during this time, hence, writting to IOARRIN
+        * must be protect by host_lock
+        */
+       pmcraid_send_cmd(cmd, pmcraid_erp_done,
+                        PMCRAID_REQUEST_SENSE_TIMEOUT,
+                        pmcraid_timeout_handler);
+}
+
+/**
+ * pmcraid_cancel_all - cancel all outstanding IOARCBs as part of error recovery
+ * @cmd: command that failed
+ * @sense: true if request_sense is required after cancel all
+ *
+ * This function sends a cancel all to a device to clear the queue.
+ */
+static void pmcraid_cancel_all(struct pmcraid_cmd *cmd, u32 sense)
+{
+       struct scsi_cmnd *scsi_cmd = cmd->scsi_cmd;
+       struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
+       struct pmcraid_resource_entry *res = scsi_cmd->device->hostdata;
+       void (*cmd_done) (struct pmcraid_cmd *) = sense ? pmcraid_erp_done
+                                                       : pmcraid_request_sense;
+
+       memset(ioarcb->cdb, 0, PMCRAID_MAX_CDB_LEN);
+       ioarcb->request_flags0 = SYNC_OVERRIDE;
+       ioarcb->request_type = REQ_TYPE_IOACMD;
+       ioarcb->cdb[0] = PMCRAID_CANCEL_ALL_REQUESTS;
+
+       if (RES_IS_GSCSI(res->cfg_entry))
+               ioarcb->cdb[1] = PMCRAID_SYNC_COMPLETE_AFTER_CANCEL;
+
+       ioarcb->ioadl_bus_addr = 0;
+       ioarcb->ioadl_length = 0;
+       ioarcb->data_transfer_length = 0;
+       ioarcb->ioarcb_bus_addr &= (~0x1FULL);
+
+       /* writing to IOARRIN must be protected by host_lock, as mid-layer
+        * schedule queuecommand while we are doing this
+        */
+       pmcraid_send_cmd(cmd, cmd_done,
+                        PMCRAID_REQUEST_SENSE_TIMEOUT,
+                        pmcraid_timeout_handler);
+}
+
+/**
+ * pmcraid_frame_auto_sense: frame fixed format sense information
+ *
+ * @cmd: pointer to failing command block
+ *
+ * Return value
+ *  none
+ */
+static void pmcraid_frame_auto_sense(struct pmcraid_cmd *cmd)
+{
+       u8 *sense_buf = cmd->scsi_cmd->sense_buffer;
+       struct pmcraid_resource_entry *res = cmd->scsi_cmd->device->hostdata;
+       struct pmcraid_ioasa *ioasa = &cmd->ioa_cb->ioasa;
+       u32 ioasc = le32_to_cpu(ioasa->ioasc);
+       u32 failing_lba = 0;
+
+       memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
+       cmd->scsi_cmd->result = SAM_STAT_CHECK_CONDITION;
+
+       if (RES_IS_VSET(res->cfg_entry) &&
+           ioasc == PMCRAID_IOASC_ME_READ_ERROR_NO_REALLOC &&
+           ioasa->u.vset.failing_lba_hi != 0) {
+
+               sense_buf[0] = 0x72;
+               sense_buf[1] = PMCRAID_IOASC_SENSE_KEY(ioasc);
+               sense_buf[2] = PMCRAID_IOASC_SENSE_CODE(ioasc);
+               sense_buf[3] = PMCRAID_IOASC_SENSE_QUAL(ioasc);
+
+               sense_buf[7] = 12;
+               sense_buf[8] = 0;
+               sense_buf[9] = 0x0A;
+               sense_buf[10] = 0x80;
+
+               failing_lba = le32_to_cpu(ioasa->u.vset.failing_lba_hi);
+
+               sense_buf[12] = (failing_lba & 0xff000000) >> 24;
+               sense_buf[13] = (failing_lba & 0x00ff0000) >> 16;
+               sense_buf[14] = (failing_lba & 0x0000ff00) >> 8;
+               sense_buf[15] = failing_lba & 0x000000ff;
+
+               failing_lba = le32_to_cpu(ioasa->u.vset.failing_lba_lo);
+
+               sense_buf[16] = (failing_lba & 0xff000000) >> 24;
+               sense_buf[17] = (failing_lba & 0x00ff0000) >> 16;
+               sense_buf[18] = (failing_lba & 0x0000ff00) >> 8;
+               sense_buf[19] = failing_lba & 0x000000ff;
+       } else {
+               sense_buf[0] = 0x70;
+               sense_buf[2] = PMCRAID_IOASC_SENSE_KEY(ioasc);
+               sense_buf[12] = PMCRAID_IOASC_SENSE_CODE(ioasc);
+               sense_buf[13] = PMCRAID_IOASC_SENSE_QUAL(ioasc);
+
+               if (ioasc == PMCRAID_IOASC_ME_READ_ERROR_NO_REALLOC) {
+                       if (RES_IS_VSET(res->cfg_entry))
+                               failing_lba =
+                                       le32_to_cpu(ioasa->u.
+                                                vset.failing_lba_lo);
+                       sense_buf[0] |= 0x80;
+                       sense_buf[3] = (failing_lba >> 24) & 0xff;
+                       sense_buf[4] = (failing_lba >> 16) & 0xff;
+                       sense_buf[5] = (failing_lba >> 8) & 0xff;
+                       sense_buf[6] = failing_lba & 0xff;
+               }
+
+               sense_buf[7] = 6; /* additional length */
+       }
+}
+
+/**
+ * pmcraid_error_handler - Error response handlers for a SCSI op
+ * @cmd: pointer to pmcraid_cmd that has failed
+ *
+ * This function determines whether or not to initiate ERP on the affected
+ * device. This is called from a tasklet, which doesn't hold any locks.
+ *
+ * Return value:
+ *      0 it caller can complete the request, otherwise 1 where in error
+ *      handler itself completes the request and returns the command block
+ *      back to free-pool
+ */
+static int pmcraid_error_handler(struct pmcraid_cmd *cmd)
+{
+       struct scsi_cmnd *scsi_cmd = cmd->scsi_cmd;
+       struct pmcraid_resource_entry *res = scsi_cmd->device->hostdata;
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       struct pmcraid_ioasa *ioasa = &cmd->ioa_cb->ioasa;
+       u32 ioasc = le32_to_cpu(ioasa->ioasc);
+       u32 masked_ioasc = ioasc & PMCRAID_IOASC_SENSE_MASK;
+       u32 sense_copied = 0;
+
+       if (!res) {
+               pmcraid_info("resource pointer is NULL\n");
+               return 0;
+       }
+
+       /* If this was a SCSI read/write command keep count of errors */
+       if (SCSI_CMD_TYPE(scsi_cmd->cmnd[0]) == SCSI_READ_CMD)
+               atomic_inc(&res->read_failures);
+       else if (SCSI_CMD_TYPE(scsi_cmd->cmnd[0]) == SCSI_WRITE_CMD)
+               atomic_inc(&res->write_failures);
+
+       if (!RES_IS_GSCSI(res->cfg_entry) &&
+               masked_ioasc != PMCRAID_IOASC_HW_DEVICE_BUS_STATUS_ERROR) {
+               pmcraid_frame_auto_sense(cmd);
+       }
+
+       /* Log IOASC/IOASA information based on user settings */
+       pmcraid_ioasc_logger(ioasc, cmd);
+
+       switch (masked_ioasc) {
+
+       case PMCRAID_IOASC_AC_TERMINATED_BY_HOST:
+               scsi_cmd->result |= (DID_ABORT << 16);
+               break;
+
+       case PMCRAID_IOASC_IR_INVALID_RESOURCE_HANDLE:
+       case PMCRAID_IOASC_HW_CANNOT_COMMUNICATE:
+               scsi_cmd->result |= (DID_NO_CONNECT << 16);
+               break;
+
+       case PMCRAID_IOASC_NR_SYNC_REQUIRED:
+               res->sync_reqd = 1;
+               scsi_cmd->result |= (DID_IMM_RETRY << 16);
+               break;
+
+       case PMCRAID_IOASC_ME_READ_ERROR_NO_REALLOC:
+               scsi_cmd->result |= (DID_PASSTHROUGH << 16);
+               break;
+
+       case PMCRAID_IOASC_UA_BUS_WAS_RESET:
+       case PMCRAID_IOASC_UA_BUS_WAS_RESET_BY_OTHER:
+               if (!res->reset_progress)
+                       scsi_report_bus_reset(pinstance->host,
+                                             scsi_cmd->device->channel);
+               scsi_cmd->result |= (DID_ERROR << 16);
+               break;
+
+       case PMCRAID_IOASC_HW_DEVICE_BUS_STATUS_ERROR:
+               scsi_cmd->result |= PMCRAID_IOASC_SENSE_STATUS(ioasc);
+               res->sync_reqd = 1;
+
+               /* if check_condition is not active return with error otherwise
+                * get/frame the sense buffer
+                */
+               if (PMCRAID_IOASC_SENSE_STATUS(ioasc) !=
+                   SAM_STAT_CHECK_CONDITION &&
+                   PMCRAID_IOASC_SENSE_STATUS(ioasc) != SAM_STAT_ACA_ACTIVE)
+                       return 0;
+
+               /* If we have auto sense data as part of IOASA pass it to
+                * mid-layer
+                */
+               if (ioasa->auto_sense_length != 0) {
+                       short sense_len = ioasa->auto_sense_length;
+                       int data_size = min_t(u16, le16_to_cpu(sense_len),
+                                             SCSI_SENSE_BUFFERSIZE);
+
+                       memcpy(scsi_cmd->sense_buffer,
+                              ioasa->sense_data,
+                              data_size);
+                       sense_copied = 1;
+               }
+
+               if (RES_IS_GSCSI(res->cfg_entry))
+                       pmcraid_cancel_all(cmd, sense_copied);
+               else if (sense_copied)
+                       pmcraid_erp_done(cmd);
+               else
+                       pmcraid_request_sense(cmd);
+
+               return 1;
+
+       case PMCRAID_IOASC_NR_INIT_CMD_REQUIRED:
+               break;
+
+       default:
+               if (PMCRAID_IOASC_SENSE_KEY(ioasc) > RECOVERED_ERROR)
+                       scsi_cmd->result |= (DID_ERROR << 16);
+               break;
+       }
+       return 0;
+}
+
+/**
+ * pmcraid_reset_device - device reset handler functions
+ *
+ * @scsi_cmd: scsi command struct
+ * @modifier: reset modifier indicating the reset sequence to be performed
+ *
+ * This function issues a device reset to the affected device.
+ * A LUN reset will be sent to the device first. If that does
+ * not work, a target reset will be sent.
+ *
+ * Return value:
+ *     SUCCESS / FAILED
+ */
+static int pmcraid_reset_device(
+       struct scsi_cmnd *scsi_cmd,
+       unsigned long timeout,
+       u8 modifier
+)
+{
+       struct pmcraid_cmd *cmd;
+       struct pmcraid_instance *pinstance;
+       struct pmcraid_resource_entry *res;
+       struct pmcraid_ioarcb *ioarcb;
+       unsigned long lock_flags;
+       u32 ioasc;
+
+       pinstance =
+               (struct pmcraid_instance *)scsi_cmd->device->host->hostdata;
+       res = scsi_cmd->device->hostdata;
+
+       if (!res) {
+               sdev_printk(KERN_ERR, scsi_cmd->device,
+                           "reset_device: NULL resource pointer\n");
+               return FAILED;
+       }
+
+       /* If adapter is currently going through reset/reload, return failed.
+        * This will force the mid-layer to call _eh_bus/host reset, which
+        * will then go to sleep and wait for the reset to complete
+        */
+       spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+       if (pinstance->ioa_reset_in_progress ||
+           pinstance->ioa_state == IOA_STATE_DEAD) {
+               spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+               return FAILED;
+       }
+
+       res->reset_progress = 1;
+       pmcraid_info("Resetting %s resource with addr %x\n",
+                    ((modifier & RESET_DEVICE_LUN) ? "LUN" :
+                    ((modifier & RESET_DEVICE_TARGET) ? "TARGET" : "BUS")),
+                    le32_to_cpu(res->cfg_entry.resource_address));
+
+       /* get a free cmd block */
+       cmd = pmcraid_get_free_cmd(pinstance);
+
+       if (cmd == NULL) {
+               spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+               pmcraid_err("%s: no cmd blocks are available\n", __func__);
+               return FAILED;
+       }
+
+       ioarcb = &cmd->ioa_cb->ioarcb;
+       ioarcb->resource_handle = res->cfg_entry.resource_handle;
+       ioarcb->request_type = REQ_TYPE_IOACMD;
+       ioarcb->cdb[0] = PMCRAID_RESET_DEVICE;
+
+       /* Initialize reset modifier bits */
+       if (modifier)
+               modifier = ENABLE_RESET_MODIFIER | modifier;
+
+       ioarcb->cdb[1] = modifier;
+
+       init_completion(&cmd->wait_for_completion);
+       cmd->completion_req = 1;
+
+       pmcraid_info("cmd(CDB[0] = %x) for %x with index = %d\n",
+                    cmd->ioa_cb->ioarcb.cdb[0],
+                    le32_to_cpu(cmd->ioa_cb->ioarcb.resource_handle),
+                    le32_to_cpu(cmd->ioa_cb->ioarcb.response_handle) >> 2);
+
+       pmcraid_send_cmd(cmd,
+                        pmcraid_internal_done,
+                        timeout,
+                        pmcraid_timeout_handler);
+
+       spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+
+       /* RESET_DEVICE command completes after all pending IOARCBs are
+        * completed. Once this command is completed, pmcraind_internal_done
+        * will wake up the 'completion' queue.
+        */
+       wait_for_completion(&cmd->wait_for_completion);
+
+       /* complete the command here itself and return the command block
+        * to free list
+        */
+       pmcraid_return_cmd(cmd);
+       res->reset_progress = 0;
+       ioasc = le32_to_cpu(cmd->ioa_cb->ioasa.ioasc);
+
+       /* set the return value based on the returned ioasc */
+       return PMCRAID_IOASC_SENSE_KEY(ioasc) ? FAILED : SUCCESS;
+}
+
+/**
+ * _pmcraid_io_done - helper for pmcraid_io_done function
+ *
+ * @cmd: pointer to pmcraid command struct
+ * @reslen: residual data length to be set in the ioasa
+ * @ioasc: ioasc either returned by IOA or set by driver itself.
+ *
+ * This function is invoked by pmcraid_io_done to complete mid-layer
+ * scsi ops.
+ *
+ * Return value:
+ *       0 if caller is required to return it to free_pool. Returns 1 if
+ *       caller need not worry about freeing command block as error handler
+ *       will take care of that.
+ */
+
+static int _pmcraid_io_done(struct pmcraid_cmd *cmd, int reslen, int ioasc)
+{
+       struct scsi_cmnd *scsi_cmd = cmd->scsi_cmd;
+       int rc = 0;
+
+       scsi_set_resid(scsi_cmd, reslen);
+
+       pmcraid_info("response(%d) CDB[0] = %x ioasc:result: %x:%x\n",
+               le32_to_cpu(cmd->ioa_cb->ioarcb.response_handle) >> 2,
+               cmd->ioa_cb->ioarcb.cdb[0],
+               ioasc, scsi_cmd->result);
+
+       if (PMCRAID_IOASC_SENSE_KEY(ioasc) != 0)
+               rc = pmcraid_error_handler(cmd);
+
+       if (rc == 0) {
+               scsi_dma_unmap(scsi_cmd);
+               scsi_cmd->scsi_done(scsi_cmd);
+       }
+
+       return rc;
+}
+
+/**
+ * pmcraid_io_done - SCSI completion function
+ *
+ * @cmd: pointer to pmcraid command struct
+ *
+ * This function is invoked by tasklet/mid-layer error handler to completing
+ * the SCSI ops sent from mid-layer.
+ *
+ * Return value
+ *       none
+ */
+
+static void pmcraid_io_done(struct pmcraid_cmd *cmd)
+{
+       u32 ioasc = le32_to_cpu(cmd->ioa_cb->ioasa.ioasc);
+       u32 reslen = le32_to_cpu(cmd->ioa_cb->ioasa.residual_data_length);
+
+       if (_pmcraid_io_done(cmd, reslen, ioasc) == 0)
+               pmcraid_return_cmd(cmd);
+}
+
+/**
+ * pmcraid_abort_cmd - Aborts a single IOARCB already submitted to IOA
+ *
+ * @cmd: command block of the command to be aborted
+ *
+ * Return Value:
+ *      returns pointer to command structure used as cancelling cmd
+ */
+static struct pmcraid_cmd *pmcraid_abort_cmd(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_cmd *cancel_cmd;
+       struct pmcraid_instance *pinstance;
+       struct pmcraid_resource_entry *res;
+
+       pinstance = (struct pmcraid_instance *)cmd->drv_inst;
+       res = cmd->scsi_cmd->device->hostdata;
+
+       cancel_cmd = pmcraid_get_free_cmd(pinstance);
+
+       if (cancel_cmd == NULL) {
+               pmcraid_err("%s: no cmd blocks are available\n", __func__);
+               return NULL;
+       }
+
+       pmcraid_prepare_cancel_cmd(cancel_cmd, cmd);
+
+       pmcraid_info("aborting command CDB[0]= %x with index = %d\n",
+               cmd->ioa_cb->ioarcb.cdb[0],
+               cmd->ioa_cb->ioarcb.response_handle >> 2);
+
+       init_completion(&cancel_cmd->wait_for_completion);
+       cancel_cmd->completion_req = 1;
+
+       pmcraid_info("command (%d) CDB[0] = %x for %x\n",
+               le32_to_cpu(cancel_cmd->ioa_cb->ioarcb.response_handle) >> 2,
+               cancel_cmd->ioa_cb->ioarcb.cdb[0],
+               le32_to_cpu(cancel_cmd->ioa_cb->ioarcb.resource_handle));
+
+       pmcraid_send_cmd(cancel_cmd,
+                        pmcraid_internal_done,
+                        PMCRAID_INTERNAL_TIMEOUT,
+                        pmcraid_timeout_handler);
+       return cancel_cmd;
+}
+
+/**
+ * pmcraid_abort_complete - Waits for ABORT TASK completion
+ *
+ * @cancel_cmd: command block use as cancelling command
+ *
+ * Return Value:
+ *      returns SUCCESS if ABORT TASK has good completion
+ *      otherwise FAILED
+ */
+static int pmcraid_abort_complete(struct pmcraid_cmd *cancel_cmd)
+{
+       struct pmcraid_resource_entry *res;
+       u32 ioasc;
+
+       wait_for_completion(&cancel_cmd->wait_for_completion);
+       res = cancel_cmd->res;
+       cancel_cmd->res = NULL;
+       ioasc = le32_to_cpu(cancel_cmd->ioa_cb->ioasa.ioasc);
+
+       /* If the abort task is not timed out we will get a Good completion
+        * as sense_key, otherwise we may get one the following responses
+        * due to subsequent bus reset or device reset. In case IOASC is
+        * NR_SYNC_REQUIRED, set sync_reqd flag for the corresponding resource
+        */
+       if (ioasc == PMCRAID_IOASC_UA_BUS_WAS_RESET ||
+           ioasc == PMCRAID_IOASC_NR_SYNC_REQUIRED) {
+               if (ioasc == PMCRAID_IOASC_NR_SYNC_REQUIRED)
+                       res->sync_reqd = 1;
+               ioasc = 0;
+       }
+
+       /* complete the command here itself */
+       pmcraid_return_cmd(cancel_cmd);
+       return PMCRAID_IOASC_SENSE_KEY(ioasc) ? FAILED : SUCCESS;
+}
+
+/**
+ * pmcraid_eh_abort_handler - entry point for aborting a single task on errors
+ *
+ * @scsi_cmd:   scsi command struct given by mid-layer. When this is called
+ *             mid-layer ensures that no other commands are queued. This
+ *             never gets called under interrupt, but a separate eh thread.
+ *
+ * Return value:
+ *      SUCCESS / FAILED
+ */
+static int pmcraid_eh_abort_handler(struct scsi_cmnd *scsi_cmd)
+{
+       struct pmcraid_instance *pinstance;
+       struct pmcraid_cmd *cmd;
+       struct pmcraid_resource_entry *res;
+       unsigned long host_lock_flags;
+       unsigned long pending_lock_flags;
+       struct pmcraid_cmd *cancel_cmd = NULL;
+       int cmd_found = 0;
+       int rc = FAILED;
+
+       pinstance =
+               (struct pmcraid_instance *)scsi_cmd->device->host->hostdata;
+
+       scmd_printk(KERN_INFO, scsi_cmd,
+                   "I/O command timed out, aborting it.\n");
+
+       res = scsi_cmd->device->hostdata;
+
+       if (res == NULL)
+               return rc;
+
+       /* If we are currently going through reset/reload, return failed.
+        * This will force the mid-layer to eventually call
+        * pmcraid_eh_host_reset which will then go to sleep and wait for the
+        * reset to complete
+        */
+       spin_lock_irqsave(pinstance->host->host_lock, host_lock_flags);
+
+       if (pinstance->ioa_reset_in_progress ||
+           pinstance->ioa_state == IOA_STATE_DEAD) {
+               spin_unlock_irqrestore(pinstance->host->host_lock,
+                                      host_lock_flags);
+               return rc;
+       }
+
+       /* loop over pending cmd list to find cmd corresponding to this
+        * scsi_cmd. Note that this command might not have been completed
+        * already. locking: all pending commands are protected with
+        * pending_pool_lock.
+        */
+       spin_lock_irqsave(&pinstance->pending_pool_lock, pending_lock_flags);
+       list_for_each_entry(cmd, &pinstance->pending_cmd_pool, free_list) {
+
+               if (cmd->scsi_cmd == scsi_cmd) {
+                       cmd_found = 1;
+                       break;
+               }
+       }
+
+       spin_unlock_irqrestore(&pinstance->pending_pool_lock,
+                               pending_lock_flags);
+
+       /* If the command to be aborted was given to IOA and still pending with
+        * it, send ABORT_TASK to abort this and wait for its completion
+        */
+       if (cmd_found)
+               cancel_cmd = pmcraid_abort_cmd(cmd);
+
+       spin_unlock_irqrestore(pinstance->host->host_lock,
+                              host_lock_flags);
+
+       if (cancel_cmd) {
+               cancel_cmd->res = cmd->scsi_cmd->device->hostdata;
+               rc = pmcraid_abort_complete(cancel_cmd);
+       }
+
+       return cmd_found ? rc : SUCCESS;
+}
+
+/**
+ * pmcraid_eh_xxxx_reset_handler - bus/target/device reset handler callbacks
+ *
+ * @scmd: pointer to scsi_cmd that was sent to the resource to be reset.
+ *
+ * All these routines invokve pmcraid_reset_device with appropriate parameters.
+ * Since these are called from mid-layer EH thread, no other IO will be queued
+ * to the resource being reset. However, control path (IOCTL) may be active so
+ * it is necessary to synchronize IOARRIN writes which pmcraid_reset_device
+ * takes care by locking/unlocking host_lock.
+ *
+ * Return value
+ *     SUCCESS or FAILED
+ */
+static int pmcraid_eh_device_reset_handler(struct scsi_cmnd *scmd)
+{
+       scmd_printk(KERN_INFO, scmd,
+                   "resetting device due to an I/O command timeout.\n");
+       return pmcraid_reset_device(scmd,
+                                   PMCRAID_INTERNAL_TIMEOUT,
+                                   RESET_DEVICE_LUN);
+}
+
+static int pmcraid_eh_bus_reset_handler(struct scsi_cmnd *scmd)
+{
+       scmd_printk(KERN_INFO, scmd,
+                   "Doing bus reset due to an I/O command timeout.\n");
+       return pmcraid_reset_device(scmd,
+                                   PMCRAID_RESET_BUS_TIMEOUT,
+                                   RESET_DEVICE_BUS);
+}
+
+static int pmcraid_eh_target_reset_handler(struct scsi_cmnd *scmd)
+{
+       scmd_printk(KERN_INFO, scmd,
+                   "Doing target reset due to an I/O command timeout.\n");
+       return pmcraid_reset_device(scmd,
+                                   PMCRAID_INTERNAL_TIMEOUT,
+                                   RESET_DEVICE_TARGET);
+}
+
+/**
+ * pmcraid_eh_host_reset_handler - adapter reset handler callback
+ *
+ * @scmd: pointer to scsi_cmd that was sent to a resource of adapter
+ *
+ * Initiates adapter reset to bring it up to operational state
+ *
+ * Return value
+ *     SUCCESS or FAILED
+ */
+static int pmcraid_eh_host_reset_handler(struct scsi_cmnd *scmd)
+{
+       unsigned long interval = 10000; /* 10 seconds interval */
+       int waits = jiffies_to_msecs(PMCRAID_RESET_HOST_TIMEOUT) / interval;
+       struct pmcraid_instance *pinstance =
+               (struct pmcraid_instance *)(scmd->device->host->hostdata);
+
+
+       /* wait for an additional 150 seconds just in case firmware could come
+        * up and if it could complete all the pending commands excluding the
+        * two HCAM (CCN and LDN).
+        */
+       while (waits--) {
+               if (atomic_read(&pinstance->outstanding_cmds) <=
+                   PMCRAID_MAX_HCAM_CMD)
+                       return SUCCESS;
+               msleep(interval);
+       }
+
+       dev_err(&pinstance->pdev->dev,
+               "Adapter being reset due to an I/O command timeout.\n");
+       return pmcraid_reset_bringup(pinstance) == 0 ? SUCCESS : FAILED;
+}
+
+/**
+ * pmcraid_init_ioadls - initializes IOADL related fields in IOARCB
+ * @cmd: pmcraid command struct
+ * @sgcount: count of scatter-gather elements
+ *
+ * Return value
+ *   returns pointer pmcraid_ioadl_desc, initialized to point to internal
+ *   or external IOADLs
+ */
+struct pmcraid_ioadl_desc *
+pmcraid_init_ioadls(struct pmcraid_cmd *cmd, int sgcount)
+{
+       struct pmcraid_ioadl_desc *ioadl;
+       struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
+       int ioadl_count = 0;
+
+       if (ioarcb->add_cmd_param_length)
+               ioadl_count = DIV_ROUND_UP(ioarcb->add_cmd_param_length, 16);
+       ioarcb->ioadl_length =
+               sizeof(struct pmcraid_ioadl_desc) * sgcount;
+
+       if ((sgcount + ioadl_count) > (ARRAY_SIZE(ioarcb->add_data.u.ioadl))) {
+               /* external ioadls start at offset 0x80 from control_block
+                * structure, re-using 24 out of 27 ioadls part of IOARCB.
+                * It is necessary to indicate to firmware that driver is
+                * using ioadls to be treated as external to IOARCB.
+                */
+               ioarcb->ioarcb_bus_addr &= ~(0x1FULL);
+               ioarcb->ioadl_bus_addr =
+                       cpu_to_le64((cmd->ioa_cb_bus_addr) +
+                               offsetof(struct pmcraid_ioarcb,
+                                       add_data.u.ioadl[3]));
+               ioadl = &ioarcb->add_data.u.ioadl[3];
+       } else {
+               ioarcb->ioadl_bus_addr =
+                       cpu_to_le64((cmd->ioa_cb_bus_addr) +
+                               offsetof(struct pmcraid_ioarcb,
+                                       add_data.u.ioadl[ioadl_count]));
+
+               ioadl = &ioarcb->add_data.u.ioadl[ioadl_count];
+               ioarcb->ioarcb_bus_addr |=
+                               DIV_ROUND_CLOSEST(sgcount + ioadl_count, 8);
+       }
+
+       return ioadl;
+}
+
+/**
+ * pmcraid_build_ioadl - Build a scatter/gather list and map the buffer
+ * @pinstance: pointer to adapter instance structure
+ * @cmd: pmcraid command struct
+ *
+ * This function is invoked by queuecommand entry point while sending a command
+ * to firmware. This builds ioadl descriptors and sets up ioarcb fields.
+ *
+ * Return value:
+ *     0 on success or -1 on failure
+ */
+static int pmcraid_build_ioadl(
+       struct pmcraid_instance *pinstance,
+       struct pmcraid_cmd *cmd
+)
+{
+       int i, nseg;
+       struct scatterlist *sglist;
+
+       struct scsi_cmnd *scsi_cmd = cmd->scsi_cmd;
+       struct pmcraid_ioarcb *ioarcb = &(cmd->ioa_cb->ioarcb);
+       struct pmcraid_ioadl_desc *ioadl = ioarcb->add_data.u.ioadl;
+
+       u32 length = scsi_bufflen(scsi_cmd);
+
+       if (!length)
+               return 0;
+
+       nseg = scsi_dma_map(scsi_cmd);
+
+       if (nseg < 0) {
+               scmd_printk(KERN_ERR, scsi_cmd, "scsi_map_dma failed!\n");
+               return -1;
+       } else if (nseg > PMCRAID_MAX_IOADLS) {
+               scsi_dma_unmap(scsi_cmd);
+               scmd_printk(KERN_ERR, scsi_cmd,
+                       "sg count is (%d) more than allowed!\n", nseg);
+               return -1;
+       }
+
+       /* Initialize IOARCB data transfer length fields */
+       if (scsi_cmd->sc_data_direction == DMA_TO_DEVICE)
+               ioarcb->request_flags0 |= TRANSFER_DIR_WRITE;
+
+       ioarcb->request_flags0 |= NO_LINK_DESCS;
+       ioarcb->data_transfer_length = cpu_to_le32(length);
+       ioadl = pmcraid_init_ioadls(cmd, nseg);
+
+       /* Initialize IOADL descriptor addresses */
+       scsi_for_each_sg(scsi_cmd, sglist, nseg, i) {
+               ioadl[i].data_len = cpu_to_le32(sg_dma_len(sglist));
+               ioadl[i].address = cpu_to_le64(sg_dma_address(sglist));
+               ioadl[i].flags = 0;
+       }
+       /* setup last descriptor */
+       ioadl[i - 1].flags = IOADL_FLAGS_LAST_DESC;
+
+       return 0;
+}
+
+/**
+ * pmcraid_free_sglist - Frees an allocated SG buffer list
+ * @sglist: scatter/gather list pointer
+ *
+ * Free a DMA'able memory previously allocated with pmcraid_alloc_sglist
+ *
+ * Return value:
+ *     none
+ */
+static void pmcraid_free_sglist(struct pmcraid_sglist *sglist)
+{
+       int i;
+
+       for (i = 0; i < sglist->num_sg; i++)
+               __free_pages(sg_page(&(sglist->scatterlist[i])),
+                            sglist->order);
+
+       kfree(sglist);
+}
+
+/**
+ * pmcraid_alloc_sglist - Allocates memory for a SG list
+ * @buflen: buffer length
+ *
+ * Allocates a DMA'able buffer in chunks and assembles a scatter/gather
+ * list.
+ *
+ * Return value
+ *     pointer to sglist / NULL on failure
+ */
+static struct pmcraid_sglist *pmcraid_alloc_sglist(int buflen)
+{
+       struct pmcraid_sglist *sglist;
+       struct scatterlist *scatterlist;
+       struct page *page;
+       int num_elem, i, j;
+       int sg_size;
+       int order;
+       int bsize_elem;
+
+       sg_size = buflen / (PMCRAID_MAX_IOADLS - 1);
+       order = (sg_size > 0) ? get_order(sg_size) : 0;
+       bsize_elem = PAGE_SIZE * (1 << order);
+
+       /* Determine the actual number of sg entries needed */
+       if (buflen % bsize_elem)
+               num_elem = (buflen / bsize_elem) + 1;
+       else
+               num_elem = buflen / bsize_elem;
+
+       /* Allocate a scatter/gather list for the DMA */
+       sglist = kzalloc(sizeof(struct pmcraid_sglist) +
+                        (sizeof(struct scatterlist) * (num_elem - 1)),
+                        GFP_KERNEL);
+
+       if (sglist == NULL)
+               return NULL;
+
+       scatterlist = sglist->scatterlist;
+       sg_init_table(scatterlist, num_elem);
+       sglist->order = order;
+       sglist->num_sg = num_elem;
+       sg_size = buflen;
+
+       for (i = 0; i < num_elem; i++) {
+               page = alloc_pages(GFP_KERNEL|GFP_DMA|__GFP_ZERO, order);
+               if (!page) {
+                       for (j = i - 1; j >= 0; j--)
+                               __free_pages(sg_page(&scatterlist[j]), order);
+                       kfree(sglist);
+                       return NULL;
+               }
+
+               sg_set_page(&scatterlist[i], page,
+                       sg_size < bsize_elem ? sg_size : bsize_elem, 0);
+               sg_size -= bsize_elem;
+       }
+
+       return sglist;
+}
+
+/**
+ * pmcraid_copy_sglist - Copy user buffer to kernel buffer's SG list
+ * @sglist: scatter/gather list pointer
+ * @buffer: buffer pointer
+ * @len: buffer length
+ * @direction: data transfer direction
+ *
+ * Copy a user buffer into a buffer allocated by pmcraid_alloc_sglist
+ *
+ * Return value:
+ * 0 on success / other on failure
+ */
+static int pmcraid_copy_sglist(
+       struct pmcraid_sglist *sglist,
+       unsigned long buffer,
+       u32 len,
+       int direction
+)
+{
+       struct scatterlist *scatterlist;
+       void *kaddr;
+       int bsize_elem;
+       int i;
+       int rc = 0;
+
+       /* Determine the actual number of bytes per element */
+       bsize_elem = PAGE_SIZE * (1 << sglist->order);
+
+       scatterlist = sglist->scatterlist;
+
+       for (i = 0; i < (len / bsize_elem); i++, buffer += bsize_elem) {
+               struct page *page = sg_page(&scatterlist[i]);
+
+               kaddr = kmap(page);
+               if (direction == DMA_TO_DEVICE)
+                       rc = __copy_from_user(kaddr,
+                                             (void *)buffer,
+                                             bsize_elem);
+               else
+                       rc = __copy_to_user((void *)buffer, kaddr, bsize_elem);
+
+               kunmap(page);
+
+               if (rc) {
+                       pmcraid_err("failed to copy user data into sg list\n");
+                       return -EFAULT;
+               }
+
+               scatterlist[i].length = bsize_elem;
+       }
+
+       if (len % bsize_elem) {
+               struct page *page = sg_page(&scatterlist[i]);
+
+               kaddr = kmap(page);
+
+               if (direction == DMA_TO_DEVICE)
+                       rc = __copy_from_user(kaddr,
+                                             (void *)buffer,
+                                             len % bsize_elem);
+               else
+                       rc = __copy_to_user((void *)buffer,
+                                           kaddr,
+                                           len % bsize_elem);
+
+               kunmap(page);
+
+               scatterlist[i].length = len % bsize_elem;
+       }
+
+       if (rc) {
+               pmcraid_err("failed to copy user data into sg list\n");
+               rc = -EFAULT;
+       }
+
+       return rc;
+}
+
+/**
+ * pmcraid_queuecommand - Queue a mid-layer request
+ * @scsi_cmd: scsi command struct
+ * @done: done function
+ *
+ * This function queues a request generated by the mid-layer. Midlayer calls
+ * this routine within host->lock. Some of the functions called by queuecommand
+ * would use cmd block queue locks (free_pool_lock and pending_pool_lock)
+ *
+ * Return value:
+ *       0 on success
+ *       SCSI_MLQUEUE_DEVICE_BUSY if device is busy
+ *       SCSI_MLQUEUE_HOST_BUSY if host is busy
+ */
+static int pmcraid_queuecommand_lck(
+       struct scsi_cmnd *scsi_cmd,
+       void (*done) (struct scsi_cmnd *)
+)
+{
+       struct pmcraid_instance *pinstance;
+       struct pmcraid_resource_entry *res;
+       struct pmcraid_ioarcb *ioarcb;
+       struct pmcraid_cmd *cmd;
+       u32 fw_version;
+       int rc = 0;
+
+       pinstance =
+               (struct pmcraid_instance *)scsi_cmd->device->host->hostdata;
+       fw_version = be16_to_cpu(pinstance->inq_data->fw_version);
+       scsi_cmd->scsi_done = done;
+       res = scsi_cmd->device->hostdata;
+       scsi_cmd->result = (DID_OK << 16);
+
+       /* if adapter is marked as dead, set result to DID_NO_CONNECT complete
+        * the command
+        */
+       if (pinstance->ioa_state == IOA_STATE_DEAD) {
+               pmcraid_info("IOA is dead, but queuecommand is scheduled\n");
+               scsi_cmd->result = (DID_NO_CONNECT << 16);
+               scsi_cmd->scsi_done(scsi_cmd);
+               return 0;
+       }
+
+       /* If IOA reset is in progress, can't queue the commands */
+       if (pinstance->ioa_reset_in_progress)
+               return SCSI_MLQUEUE_HOST_BUSY;
+
+       /* Firmware doesn't support SYNCHRONIZE_CACHE command (0x35), complete
+        * the command here itself with success return
+        */
+       if (scsi_cmd->cmnd[0] == SYNCHRONIZE_CACHE) {
+               pmcraid_info("SYNC_CACHE(0x35), completing in driver itself\n");
+               scsi_cmd->scsi_done(scsi_cmd);
+               return 0;
+       }
+
+       /* initialize the command and IOARCB to be sent to IOA */
+       cmd = pmcraid_get_free_cmd(pinstance);
+
+       if (cmd == NULL) {
+               pmcraid_err("free command block is not available\n");
+               return SCSI_MLQUEUE_HOST_BUSY;
+       }
+
+       cmd->scsi_cmd = scsi_cmd;
+       ioarcb = &(cmd->ioa_cb->ioarcb);
+       memcpy(ioarcb->cdb, scsi_cmd->cmnd, scsi_cmd->cmd_len);
+       ioarcb->resource_handle = res->cfg_entry.resource_handle;
+       ioarcb->request_type = REQ_TYPE_SCSI;
+
+       /* set hrrq number where the IOA should respond to. Note that all cmds
+        * generated internally uses hrrq_id 0, exception to this is the cmd
+        * block of scsi_cmd which is re-used (e.g. cancel/abort), which uses
+        * hrrq_id assigned here in queuecommand
+        */
+       ioarcb->hrrq_id = atomic_add_return(1, &(pinstance->last_message_id)) %
+                         pinstance->num_hrrq;
+       cmd->cmd_done = pmcraid_io_done;
+
+       if (RES_IS_GSCSI(res->cfg_entry) || RES_IS_VSET(res->cfg_entry)) {
+               if (scsi_cmd->underflow == 0)
+                       ioarcb->request_flags0 |= INHIBIT_UL_CHECK;
+
+               if (res->sync_reqd) {
+                       ioarcb->request_flags0 |= SYNC_COMPLETE;
+                       res->sync_reqd = 0;
+               }
+
+               ioarcb->request_flags0 |= NO_LINK_DESCS;
+
+               if (scsi_cmd->flags & SCMD_TAGGED)
+                       ioarcb->request_flags1 |= TASK_TAG_SIMPLE;
+
+               if (RES_IS_GSCSI(res->cfg_entry))
+                       ioarcb->request_flags1 |= DELAY_AFTER_RESET;
+       }
+
+       rc = pmcraid_build_ioadl(pinstance, cmd);
+
+       pmcraid_info("command (%d) CDB[0] = %x for %x:%x:%x:%x\n",
+                    le32_to_cpu(ioarcb->response_handle) >> 2,
+                    scsi_cmd->cmnd[0], pinstance->host->unique_id,
+                    RES_IS_VSET(res->cfg_entry) ? PMCRAID_VSET_BUS_ID :
+                       PMCRAID_PHYS_BUS_ID,
+                    RES_IS_VSET(res->cfg_entry) ?
+                       (fw_version <= PMCRAID_FW_VERSION_1 ?
+                               res->cfg_entry.unique_flags1 :
+                                       res->cfg_entry.array_id & 0xFF) :
+                       RES_TARGET(res->cfg_entry.resource_address),
+                    RES_LUN(res->cfg_entry.resource_address));
+
+       if (likely(rc == 0)) {
+               _pmcraid_fire_command(cmd);
+       } else {
+               pmcraid_err("queuecommand could not build ioadl\n");
+               pmcraid_return_cmd(cmd);
+               rc = SCSI_MLQUEUE_HOST_BUSY;
+       }
+
+       return rc;
+}
+
+static DEF_SCSI_QCMD(pmcraid_queuecommand)
+
+/**
+ * pmcraid_open -char node "open" entry, allowed only users with admin access
+ */
+static int pmcraid_chr_open(struct inode *inode, struct file *filep)
+{
+       struct pmcraid_instance *pinstance;
+
+       if (!capable(CAP_SYS_ADMIN))
+               return -EACCES;
+
+       /* Populate adapter instance * pointer for use by ioctl */
+       pinstance = container_of(inode->i_cdev, struct pmcraid_instance, cdev);
+       filep->private_data = pinstance;
+
+       return 0;
+}
+
+/**
+ * pmcraid_fasync - Async notifier registration from applications
+ *
+ * This function adds the calling process to a driver global queue. When an
+ * event occurs, SIGIO will be sent to all processes in this queue.
+ */
+static int pmcraid_chr_fasync(int fd, struct file *filep, int mode)
+{
+       struct pmcraid_instance *pinstance;
+       int rc;
+
+       pinstance = filep->private_data;
+       mutex_lock(&pinstance->aen_queue_lock);
+       rc = fasync_helper(fd, filep, mode, &pinstance->aen_queue);
+       mutex_unlock(&pinstance->aen_queue_lock);
+
+       return rc;
+}
+
+
+/**
+ * pmcraid_build_passthrough_ioadls - builds SG elements for passthrough
+ * commands sent over IOCTL interface
+ *
+ * @cmd       : pointer to struct pmcraid_cmd
+ * @buflen    : length of the request buffer
+ * @direction : data transfer direction
+ *
+ * Return value
+ *  0 on success, non-zero error code on failure
+ */
+static int pmcraid_build_passthrough_ioadls(
+       struct pmcraid_cmd *cmd,
+       int buflen,
+       int direction
+)
+{
+       struct pmcraid_sglist *sglist = NULL;
+       struct scatterlist *sg = NULL;
+       struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
+       struct pmcraid_ioadl_desc *ioadl;
+       int i;
+
+       sglist = pmcraid_alloc_sglist(buflen);
+
+       if (!sglist) {
+               pmcraid_err("can't allocate memory for passthrough SGls\n");
+               return -ENOMEM;
+       }
+
+       sglist->num_dma_sg = pci_map_sg(cmd->drv_inst->pdev,
+                                       sglist->scatterlist,
+                                       sglist->num_sg, direction);
+
+       if (!sglist->num_dma_sg || sglist->num_dma_sg > PMCRAID_MAX_IOADLS) {
+               dev_err(&cmd->drv_inst->pdev->dev,
+                       "Failed to map passthrough buffer!\n");
+               pmcraid_free_sglist(sglist);
+               return -EIO;
+       }
+
+       cmd->sglist = sglist;
+       ioarcb->request_flags0 |= NO_LINK_DESCS;
+
+       ioadl = pmcraid_init_ioadls(cmd, sglist->num_dma_sg);
+
+       /* Initialize IOADL descriptor addresses */
+       for_each_sg(sglist->scatterlist, sg, sglist->num_dma_sg, i) {
+               ioadl[i].data_len = cpu_to_le32(sg_dma_len(sg));
+               ioadl[i].address = cpu_to_le64(sg_dma_address(sg));
+               ioadl[i].flags = 0;
+       }
+
+       /* setup the last descriptor */
+       ioadl[i - 1].flags = IOADL_FLAGS_LAST_DESC;
+
+       return 0;
+}
+
+
+/**
+ * pmcraid_release_passthrough_ioadls - release passthrough ioadls
+ *
+ * @cmd: pointer to struct pmcraid_cmd for which ioadls were allocated
+ * @buflen: size of the request buffer
+ * @direction: data transfer direction
+ *
+ * Return value
+ *  0 on success, non-zero error code on failure
+ */
+static void pmcraid_release_passthrough_ioadls(
+       struct pmcraid_cmd *cmd,
+       int buflen,
+       int direction
+)
+{
+       struct pmcraid_sglist *sglist = cmd->sglist;
+
+       if (buflen > 0) {
+               pci_unmap_sg(cmd->drv_inst->pdev,
+                            sglist->scatterlist,
+                            sglist->num_sg,
+                            direction);
+               pmcraid_free_sglist(sglist);
+               cmd->sglist = NULL;
+       }
+}
+
+/**
+ * pmcraid_ioctl_passthrough - handling passthrough IOCTL commands
+ *
+ * @pinstance: pointer to adapter instance structure
+ * @cmd: ioctl code
+ * @arg: pointer to pmcraid_passthrough_buffer user buffer
+ *
+ * Return value
+ *  0 on success, non-zero error code on failure
+ */
+static long pmcraid_ioctl_passthrough(
+       struct pmcraid_instance *pinstance,
+       unsigned int ioctl_cmd,
+       unsigned int buflen,
+       unsigned long arg
+)
+{
+       struct pmcraid_passthrough_ioctl_buffer *buffer;
+       struct pmcraid_ioarcb *ioarcb;
+       struct pmcraid_cmd *cmd;
+       struct pmcraid_cmd *cancel_cmd;
+       unsigned long request_buffer;
+       unsigned long request_offset;
+       unsigned long lock_flags;
+       void *ioasa;
+       u32 ioasc;
+       int request_size;
+       int buffer_size;
+       u8 access, direction;
+       int rc = 0;
+
+       /* If IOA reset is in progress, wait 10 secs for reset to complete */
+       if (pinstance->ioa_reset_in_progress) {
+               rc = wait_event_interruptible_timeout(
+                               pinstance->reset_wait_q,
+                               !pinstance->ioa_reset_in_progress,
+                               msecs_to_jiffies(10000));
+
+               if (!rc)
+                       return -ETIMEDOUT;
+               else if (rc < 0)
+                       return -ERESTARTSYS;
+       }
+
+       /* If adapter is not in operational state, return error */
+       if (pinstance->ioa_state != IOA_STATE_OPERATIONAL) {
+               pmcraid_err("IOA is not operational\n");
+               return -ENOTTY;
+       }
+
+       buffer_size = sizeof(struct pmcraid_passthrough_ioctl_buffer);
+       buffer = kmalloc(buffer_size, GFP_KERNEL);
+
+       if (!buffer) {
+               pmcraid_err("no memory for passthrough buffer\n");
+               return -ENOMEM;
+       }
+
+       request_offset =
+           offsetof(struct pmcraid_passthrough_ioctl_buffer, request_buffer);
+
+       request_buffer = arg + request_offset;
+
+       rc = __copy_from_user(buffer,
+                            (struct pmcraid_passthrough_ioctl_buffer *) arg,
+                            sizeof(struct pmcraid_passthrough_ioctl_buffer));
+
+       ioasa =
+       (void *)(arg +
+               offsetof(struct pmcraid_passthrough_ioctl_buffer, ioasa));
+
+       if (rc) {
+               pmcraid_err("ioctl: can't copy passthrough buffer\n");
+               rc = -EFAULT;
+               goto out_free_buffer;
+       }
+
+       request_size = buffer->ioarcb.data_transfer_length;
+
+       if (buffer->ioarcb.request_flags0 & TRANSFER_DIR_WRITE) {
+               access = VERIFY_READ;
+               direction = DMA_TO_DEVICE;
+       } else {
+               access = VERIFY_WRITE;
+               direction = DMA_FROM_DEVICE;
+       }
+
+       if (request_size > 0) {
+               rc = access_ok(access, arg, request_offset + request_size);
+
+               if (!rc) {
+                       rc = -EFAULT;
+                       goto out_free_buffer;
+               }
+       } else if (request_size < 0) {
+               rc = -EINVAL;
+               goto out_free_buffer;
+       }
+
+       /* check if we have any additional command parameters */
+       if (buffer->ioarcb.add_cmd_param_length > PMCRAID_ADD_CMD_PARAM_LEN) {
+               rc = -EINVAL;
+               goto out_free_buffer;
+       }
+
+       cmd = pmcraid_get_free_cmd(pinstance);
+
+       if (!cmd) {
+               pmcraid_err("free command block is not available\n");
+               rc = -ENOMEM;
+               goto out_free_buffer;
+       }
+
+       cmd->scsi_cmd = NULL;
+       ioarcb = &(cmd->ioa_cb->ioarcb);
+
+       /* Copy the user-provided IOARCB stuff field by field */
+       ioarcb->resource_handle = buffer->ioarcb.resource_handle;
+       ioarcb->data_transfer_length = buffer->ioarcb.data_transfer_length;
+       ioarcb->cmd_timeout = buffer->ioarcb.cmd_timeout;
+       ioarcb->request_type = buffer->ioarcb.request_type;
+       ioarcb->request_flags0 = buffer->ioarcb.request_flags0;
+       ioarcb->request_flags1 = buffer->ioarcb.request_flags1;
+       memcpy(ioarcb->cdb, buffer->ioarcb.cdb, PMCRAID_MAX_CDB_LEN);
+
+       if (buffer->ioarcb.add_cmd_param_length) {
+               ioarcb->add_cmd_param_length =
+                       buffer->ioarcb.add_cmd_param_length;
+               ioarcb->add_cmd_param_offset =
+                       buffer->ioarcb.add_cmd_param_offset;
+               memcpy(ioarcb->add_data.u.add_cmd_params,
+                       buffer->ioarcb.add_data.u.add_cmd_params,
+                       buffer->ioarcb.add_cmd_param_length);
+       }
+
+       /* set hrrq number where the IOA should respond to. Note that all cmds
+        * generated internally uses hrrq_id 0, exception to this is the cmd
+        * block of scsi_cmd which is re-used (e.g. cancel/abort), which uses
+        * hrrq_id assigned here in queuecommand
+        */
+       ioarcb->hrrq_id = atomic_add_return(1, &(pinstance->last_message_id)) %
+                         pinstance->num_hrrq;
+
+       if (request_size) {
+               rc = pmcraid_build_passthrough_ioadls(cmd,
+                                                     request_size,
+                                                     direction);
+               if (rc) {
+                       pmcraid_err("couldn't build passthrough ioadls\n");
+                       goto out_free_buffer;
+               }
+       } else if (request_size < 0) {
+               rc = -EINVAL;
+               goto out_free_buffer;
+       }
+
+       /* If data is being written into the device, copy the data from user
+        * buffers
+        */
+       if (direction == DMA_TO_DEVICE && request_size > 0) {
+               rc = pmcraid_copy_sglist(cmd->sglist,
+                                        request_buffer,
+                                        request_size,
+                                        direction);
+               if (rc) {
+                       pmcraid_err("failed to copy user buffer\n");
+                       goto out_free_sglist;
+               }
+       }
+
+       /* passthrough ioctl is a blocking command so, put the user to sleep
+        * until timeout. Note that a timeout value of 0 means, do timeout.
+        */
+       cmd->cmd_done = pmcraid_internal_done;
+       init_completion(&cmd->wait_for_completion);
+       cmd->completion_req = 1;
+
+       pmcraid_info("command(%d) (CDB[0] = %x) for %x\n",
+                    le32_to_cpu(cmd->ioa_cb->ioarcb.response_handle) >> 2,
+                    cmd->ioa_cb->ioarcb.cdb[0],
+                    le32_to_cpu(cmd->ioa_cb->ioarcb.resource_handle));
+
+       spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+       _pmcraid_fire_command(cmd);
+       spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+
+       /* NOTE ! Remove the below line once abort_task is implemented
+        * in firmware. This line disables ioctl command timeout handling logic
+        * similar to IO command timeout handling, making ioctl commands to wait
+        * until the command completion regardless of timeout value specified in
+        * ioarcb
+        */
+       buffer->ioarcb.cmd_timeout = 0;
+
+       /* If command timeout is specified put caller to wait till that time,
+        * otherwise it would be blocking wait. If command gets timed out, it
+        * will be aborted.
+        */
+       if (buffer->ioarcb.cmd_timeout == 0) {
+               wait_for_completion(&cmd->wait_for_completion);
+       } else if (!wait_for_completion_timeout(
+                       &cmd->wait_for_completion,
+                       msecs_to_jiffies(buffer->ioarcb.cmd_timeout * 1000))) {
+
+               pmcraid_info("aborting cmd %d (CDB[0] = %x) due to timeout\n",
+                       le32_to_cpu(cmd->ioa_cb->ioarcb.response_handle >> 2),
+                       cmd->ioa_cb->ioarcb.cdb[0]);
+
+               spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+               cancel_cmd = pmcraid_abort_cmd(cmd);
+               spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+
+               if (cancel_cmd) {
+                       wait_for_completion(&cancel_cmd->wait_for_completion);
+                       ioasc = cancel_cmd->ioa_cb->ioasa.ioasc;
+                       pmcraid_return_cmd(cancel_cmd);
+
+                       /* if abort task couldn't find the command i.e it got
+                        * completed prior to aborting, return good completion.
+                        * if command got aborted successfully or there was IOA
+                        * reset due to abort task itself getting timedout then
+                        * return -ETIMEDOUT
+                        */
+                       if (ioasc == PMCRAID_IOASC_IOA_WAS_RESET ||
+                           PMCRAID_IOASC_SENSE_KEY(ioasc) == 0x00) {
+                               if (ioasc != PMCRAID_IOASC_GC_IOARCB_NOTFOUND)
+                                       rc = -ETIMEDOUT;
+                               goto out_handle_response;
+                       }
+               }
+
+               /* no command block for abort task or abort task failed to abort
+                * the IOARCB, then wait for 150 more seconds and initiate reset
+                * sequence after timeout
+                */
+               if (!wait_for_completion_timeout(
+                       &cmd->wait_for_completion,
+                       msecs_to_jiffies(150 * 1000))) {
+                       pmcraid_reset_bringup(cmd->drv_inst);
+                       rc = -ETIMEDOUT;
+               }
+       }
+
+out_handle_response:
+       /* copy entire IOASA buffer and return IOCTL success.
+        * If copying IOASA to user-buffer fails, return
+        * EFAULT
+        */
+       if (copy_to_user(ioasa, &cmd->ioa_cb->ioasa,
+               sizeof(struct pmcraid_ioasa))) {
+               pmcraid_err("failed to copy ioasa buffer to user\n");
+               rc = -EFAULT;
+       }
+
+       /* If the data transfer was from device, copy the data onto user
+        * buffers
+        */
+       else if (direction == DMA_FROM_DEVICE && request_size > 0) {
+               rc = pmcraid_copy_sglist(cmd->sglist,
+                                        request_buffer,
+                                        request_size,
+                                        direction);
+               if (rc) {
+                       pmcraid_err("failed to copy user buffer\n");
+                       rc = -EFAULT;
+               }
+       }
+
+out_free_sglist:
+       pmcraid_release_passthrough_ioadls(cmd, request_size, direction);
+       pmcraid_return_cmd(cmd);
+
+out_free_buffer:
+       kfree(buffer);
+
+       return rc;
+}
+
+
+
+
+/**
+ * pmcraid_ioctl_driver - ioctl handler for commands handled by driver itself
+ *
+ * @pinstance: pointer to adapter instance structure
+ * @cmd: ioctl command passed in
+ * @buflen: length of user_buffer
+ * @user_buffer: user buffer pointer
+ *
+ * Return Value
+ *   0 in case of success, otherwise appropriate error code
+ */
+static long pmcraid_ioctl_driver(
+       struct pmcraid_instance *pinstance,
+       unsigned int cmd,
+       unsigned int buflen,
+       void __user *user_buffer
+)
+{
+       int rc = -ENOSYS;
+
+       if (!access_ok(VERIFY_READ, user_buffer, _IOC_SIZE(cmd))) {
+               pmcraid_err("ioctl_driver: access fault in request buffer\n");
+               return -EFAULT;
+       }
+
+       switch (cmd) {
+       case PMCRAID_IOCTL_RESET_ADAPTER:
+               pmcraid_reset_bringup(pinstance);
+               rc = 0;
+               break;
+
+       default:
+               break;
+       }
+
+       return rc;
+}
+
+/**
+ * pmcraid_check_ioctl_buffer - check for proper access to user buffer
+ *
+ * @cmd: ioctl command
+ * @arg: user buffer
+ * @hdr: pointer to kernel memory for pmcraid_ioctl_header
+ *
+ * Return Value
+ *     negetive error code if there are access issues, otherwise zero.
+ *     Upon success, returns ioctl header copied out of user buffer.
+ */
+
+static int pmcraid_check_ioctl_buffer(
+       int cmd,
+       void __user *arg,
+       struct pmcraid_ioctl_header *hdr
+)
+{
+       int rc = 0;
+       int access = VERIFY_READ;
+
+       if (copy_from_user(hdr, arg, sizeof(struct pmcraid_ioctl_header))) {
+               pmcraid_err("couldn't copy ioctl header from user buffer\n");
+               return -EFAULT;
+       }
+
+       /* check for valid driver signature */
+       rc = memcmp(hdr->signature,
+                   PMCRAID_IOCTL_SIGNATURE,
+                   sizeof(hdr->signature));
+       if (rc) {
+               pmcraid_err("signature verification failed\n");
+               return -EINVAL;
+       }
+
+       /* check for appropriate buffer access */
+       if ((_IOC_DIR(cmd) & _IOC_READ) == _IOC_READ)
+               access = VERIFY_WRITE;
+
+       rc = access_ok(access,
+                      (arg + sizeof(struct pmcraid_ioctl_header)),
+                      hdr->buffer_length);
+       if (!rc) {
+               pmcraid_err("access failed for user buffer of size %d\n",
+                            hdr->buffer_length);
+               return -EFAULT;
+       }
+
+       return 0;
+}
+
+/**
+ *  pmcraid_ioctl - char node ioctl entry point
+ */
+static long pmcraid_chr_ioctl(
+       struct file *filep,
+       unsigned int cmd,
+       unsigned long arg
+)
+{
+       struct pmcraid_instance *pinstance = NULL;
+       struct pmcraid_ioctl_header *hdr = NULL;
+       int retval = -ENOTTY;
+
+       hdr = kmalloc(sizeof(struct pmcraid_ioctl_header), GFP_KERNEL);
+
+       if (!hdr) {
+               pmcraid_err("failed to allocate memory for ioctl header\n");
+               return -ENOMEM;
+       }
+
+       retval = pmcraid_check_ioctl_buffer(cmd, (void *)arg, hdr);
+
+       if (retval) {
+               pmcraid_info("chr_ioctl: header check failed\n");
+               kfree(hdr);
+               return retval;
+       }
+
+       pinstance = filep->private_data;
+
+       if (!pinstance) {
+               pmcraid_info("adapter instance is not found\n");
+               kfree(hdr);
+               return -ENOTTY;
+       }
+
+       switch (_IOC_TYPE(cmd)) {
+
+       case PMCRAID_PASSTHROUGH_IOCTL:
+               /* If ioctl code is to download microcode, we need to block
+                * mid-layer requests.
+                */
+               if (cmd == PMCRAID_IOCTL_DOWNLOAD_MICROCODE)
+                       scsi_block_requests(pinstance->host);
+
+               retval = pmcraid_ioctl_passthrough(pinstance,
+                                                  cmd,
+                                                  hdr->buffer_length,
+                                                  arg);
+
+               if (cmd == PMCRAID_IOCTL_DOWNLOAD_MICROCODE)
+                       scsi_unblock_requests(pinstance->host);
+               break;
+
+       case PMCRAID_DRIVER_IOCTL:
+               arg += sizeof(struct pmcraid_ioctl_header);
+               retval = pmcraid_ioctl_driver(pinstance,
+                                             cmd,
+                                             hdr->buffer_length,
+                                             (void __user *)arg);
+               break;
+
+       default:
+               retval = -ENOTTY;
+               break;
+       }
+
+       kfree(hdr);
+
+       return retval;
+}
+
+/**
+ * File operations structure for management interface
+ */
+static const struct file_operations pmcraid_fops = {
+       .owner = THIS_MODULE,
+       .open = pmcraid_chr_open,
+       .fasync = pmcraid_chr_fasync,
+       .unlocked_ioctl = pmcraid_chr_ioctl,
+#ifdef CONFIG_COMPAT
+       .compat_ioctl = pmcraid_chr_ioctl,
+#endif
+       .llseek = noop_llseek,
+};
+
+
+
+
+/**
+ * pmcraid_show_log_level - Display adapter's error logging level
+ * @dev: class device struct
+ * @buf: buffer
+ *
+ * Return value:
+ *  number of bytes printed to buffer
+ */
+static ssize_t pmcraid_show_log_level(
+       struct device *dev,
+       struct device_attribute *attr,
+       char *buf)
+{
+       struct Scsi_Host *shost = class_to_shost(dev);
+       struct pmcraid_instance *pinstance =
+               (struct pmcraid_instance *)shost->hostdata;
+       return snprintf(buf, PAGE_SIZE, "%d\n", pinstance->current_log_level);
+}
+
+/**
+ * pmcraid_store_log_level - Change the adapter's error logging level
+ * @dev: class device struct
+ * @buf: buffer
+ * @count: not used
+ *
+ * Return value:
+ *  number of bytes printed to buffer
+ */
+static ssize_t pmcraid_store_log_level(
+       struct device *dev,
+       struct device_attribute *attr,
+       const char *buf,
+       size_t count
+)
+{
+       struct Scsi_Host *shost;
+       struct pmcraid_instance *pinstance;
+       u8 val;
+
+       if (kstrtou8(buf, 10, &val))
+               return -EINVAL;
+       /* log-level should be from 0 to 2 */
+       if (val > 2)
+               return -EINVAL;
+
+       shost = class_to_shost(dev);
+       pinstance = (struct pmcraid_instance *)shost->hostdata;
+       pinstance->current_log_level = val;
+
+       return strlen(buf);
+}
+
+static struct device_attribute pmcraid_log_level_attr = {
+       .attr = {
+                .name = "log_level",
+                .mode = S_IRUGO | S_IWUSR,
+                },
+       .show = pmcraid_show_log_level,
+       .store = pmcraid_store_log_level,
+};
+
+/**
+ * pmcraid_show_drv_version - Display driver version
+ * @dev: class device struct
+ * @buf: buffer
+ *
+ * Return value:
+ *  number of bytes printed to buffer
+ */
+static ssize_t pmcraid_show_drv_version(
+       struct device *dev,
+       struct device_attribute *attr,
+       char *buf
+)
+{
+       return snprintf(buf, PAGE_SIZE, "version: %s\n",
+                       PMCRAID_DRIVER_VERSION);
+}
+
+static struct device_attribute pmcraid_driver_version_attr = {
+       .attr = {
+                .name = "drv_version",
+                .mode = S_IRUGO,
+                },
+       .show = pmcraid_show_drv_version,
+};
+
+/**
+ * pmcraid_show_io_adapter_id - Display driver assigned adapter id
+ * @dev: class device struct
+ * @buf: buffer
+ *
+ * Return value:
+ *  number of bytes printed to buffer
+ */
+static ssize_t pmcraid_show_adapter_id(
+       struct device *dev,
+       struct device_attribute *attr,
+       char *buf
+)
+{
+       struct Scsi_Host *shost = class_to_shost(dev);
+       struct pmcraid_instance *pinstance =
+               (struct pmcraid_instance *)shost->hostdata;
+       u32 adapter_id = (pinstance->pdev->bus->number << 8) |
+               pinstance->pdev->devfn;
+       u32 aen_group = pmcraid_event_family.id;
+
+       return snprintf(buf, PAGE_SIZE,
+                       "adapter id: %d\nminor: %d\naen group: %d\n",
+                       adapter_id, MINOR(pinstance->cdev.dev), aen_group);
+}
+
+static struct device_attribute pmcraid_adapter_id_attr = {
+       .attr = {
+                .name = "adapter_id",
+                .mode = S_IRUGO,
+                },
+       .show = pmcraid_show_adapter_id,
+};
+
+static struct device_attribute *pmcraid_host_attrs[] = {
+       &pmcraid_log_level_attr,
+       &pmcraid_driver_version_attr,
+       &pmcraid_adapter_id_attr,
+       NULL,
+};
+
+
+/* host template structure for pmcraid driver */
+static struct scsi_host_template pmcraid_host_template = {
+       .module = THIS_MODULE,
+       .name = PMCRAID_DRIVER_NAME,
+       .queuecommand = pmcraid_queuecommand,
+       .eh_abort_handler = pmcraid_eh_abort_handler,
+       .eh_bus_reset_handler = pmcraid_eh_bus_reset_handler,
+       .eh_target_reset_handler = pmcraid_eh_target_reset_handler,
+       .eh_device_reset_handler = pmcraid_eh_device_reset_handler,
+       .eh_host_reset_handler = pmcraid_eh_host_reset_handler,
+
+       .slave_alloc = pmcraid_slave_alloc,
+       .slave_configure = pmcraid_slave_configure,
+       .slave_destroy = pmcraid_slave_destroy,
+       .change_queue_depth = pmcraid_change_queue_depth,
+       .can_queue = PMCRAID_MAX_IO_CMD,
+       .this_id = -1,
+       .sg_tablesize = PMCRAID_MAX_IOADLS,
+       .max_sectors = PMCRAID_IOA_MAX_SECTORS,
+       .no_write_same = 1,
+       .cmd_per_lun = PMCRAID_MAX_CMD_PER_LUN,
+       .use_clustering = ENABLE_CLUSTERING,
+       .shost_attrs = pmcraid_host_attrs,
+       .proc_name = PMCRAID_DRIVER_NAME,
+       .use_blk_tags = 1,
+};
+
+/*
+ * pmcraid_isr_msix - implements MSI-X interrupt handling routine
+ * @irq: interrupt vector number
+ * @dev_id: pointer hrrq_vector
+ *
+ * Return Value
+ *      IRQ_HANDLED if interrupt is handled or IRQ_NONE if ignored
+ */
+
+static irqreturn_t pmcraid_isr_msix(int irq, void *dev_id)
+{
+       struct pmcraid_isr_param *hrrq_vector;
+       struct pmcraid_instance *pinstance;
+       unsigned long lock_flags;
+       u32 intrs_val;
+       int hrrq_id;
+
+       hrrq_vector = (struct pmcraid_isr_param *)dev_id;
+       hrrq_id = hrrq_vector->hrrq_id;
+       pinstance = hrrq_vector->drv_inst;
+
+       if (!hrrq_id) {
+               /* Read the interrupt */
+               intrs_val = pmcraid_read_interrupts(pinstance);
+               if (intrs_val &&
+                       ((ioread32(pinstance->int_regs.host_ioa_interrupt_reg)
+                       & DOORBELL_INTR_MSIX_CLR) == 0)) {
+                       /* Any error interrupts including unit_check,
+                        * initiate IOA reset.In case of unit check indicate
+                        * to reset_sequence that IOA unit checked and prepare
+                        * for a dump during reset sequence
+                        */
+                       if (intrs_val & PMCRAID_ERROR_INTERRUPTS) {
+                               if (intrs_val & INTRS_IOA_UNIT_CHECK)
+                                       pinstance->ioa_unit_check = 1;
+
+                               pmcraid_err("ISR: error interrupts: %x \
+                                       initiating reset\n", intrs_val);
+                               spin_lock_irqsave(pinstance->host->host_lock,
+                                       lock_flags);
+                               pmcraid_initiate_reset(pinstance);
+                               spin_unlock_irqrestore(
+                                       pinstance->host->host_lock,
+                                       lock_flags);
+                       }
+                       /* If interrupt was as part of the ioa initialization,
+                        * clear it. Delete the timer and wakeup the
+                        * reset engine to proceed with reset sequence
+                        */
+                       if (intrs_val & INTRS_TRANSITION_TO_OPERATIONAL)
+                               pmcraid_clr_trans_op(pinstance);
+
+                       /* Clear the interrupt register by writing
+                        * to host to ioa doorbell. Once done
+                        * FW will clear the interrupt.
+                        */
+                       iowrite32(DOORBELL_INTR_MSIX_CLR,
+                               pinstance->int_regs.host_ioa_interrupt_reg);
+                       ioread32(pinstance->int_regs.host_ioa_interrupt_reg);
+
+
+               }
+       }
+
+       tasklet_schedule(&(pinstance->isr_tasklet[hrrq_id]));
+
+       return IRQ_HANDLED;
+}
+
+/**
+ * pmcraid_isr  - implements legacy interrupt handling routine
+ *
+ * @irq: interrupt vector number
+ * @dev_id: pointer hrrq_vector
+ *
+ * Return Value
+ *      IRQ_HANDLED if interrupt is handled or IRQ_NONE if ignored
+ */
+static irqreturn_t pmcraid_isr(int irq, void *dev_id)
+{
+       struct pmcraid_isr_param *hrrq_vector;
+       struct pmcraid_instance *pinstance;
+       u32 intrs;
+       unsigned long lock_flags;
+       int hrrq_id = 0;
+
+       /* In case of legacy interrupt mode where interrupts are shared across
+        * isrs, it may be possible that the current interrupt is not from IOA
+        */
+       if (!dev_id) {
+               printk(KERN_INFO "%s(): NULL host pointer\n", __func__);
+               return IRQ_NONE;
+       }
+       hrrq_vector = (struct pmcraid_isr_param *)dev_id;
+       pinstance = hrrq_vector->drv_inst;
+
+       intrs = pmcraid_read_interrupts(pinstance);
+
+       if (unlikely((intrs & PMCRAID_PCI_INTERRUPTS) == 0))
+               return IRQ_NONE;
+
+       /* Any error interrupts including unit_check, initiate IOA reset.
+        * In case of unit check indicate to reset_sequence that IOA unit
+        * checked and prepare for a dump during reset sequence
+        */
+       if (intrs & PMCRAID_ERROR_INTERRUPTS) {
+
+               if (intrs & INTRS_IOA_UNIT_CHECK)
+                       pinstance->ioa_unit_check = 1;
+
+               iowrite32(intrs,
+                         pinstance->int_regs.ioa_host_interrupt_clr_reg);
+               pmcraid_err("ISR: error interrupts: %x initiating reset\n",
+                           intrs);
+               intrs = ioread32(
+                               pinstance->int_regs.ioa_host_interrupt_clr_reg);
+               spin_lock_irqsave(pinstance->host->host_lock, lock_flags);
+               pmcraid_initiate_reset(pinstance);
+               spin_unlock_irqrestore(pinstance->host->host_lock, lock_flags);
+       } else {
+               /* If interrupt was as part of the ioa initialization,
+                * clear. Delete the timer and wakeup the
+                * reset engine to proceed with reset sequence
+                */
+               if (intrs & INTRS_TRANSITION_TO_OPERATIONAL) {
+                       pmcraid_clr_trans_op(pinstance);
+               } else {
+                       iowrite32(intrs,
+                               pinstance->int_regs.ioa_host_interrupt_clr_reg);
+                       ioread32(
+                               pinstance->int_regs.ioa_host_interrupt_clr_reg);
+
+                       tasklet_schedule(
+                                       &(pinstance->isr_tasklet[hrrq_id]));
+               }
+       }
+
+       return IRQ_HANDLED;
+}
+
+
+/**
+ * pmcraid_worker_function -  worker thread function
+ *
+ * @workp: pointer to struct work queue
+ *
+ * Return Value
+ *      None
+ */
+
+static void pmcraid_worker_function(struct work_struct *workp)
+{
+       struct pmcraid_instance *pinstance;
+       struct pmcraid_resource_entry *res;
+       struct pmcraid_resource_entry *temp;
+       struct scsi_device *sdev;
+       unsigned long lock_flags;
+       unsigned long host_lock_flags;
+       u16 fw_version;
+       u8 bus, target, lun;
+
+       pinstance = container_of(workp, struct pmcraid_instance, worker_q);
+       /* add resources only after host is added into system */
+       if (!atomic_read(&pinstance->expose_resources))
+               return;
+
+       fw_version = be16_to_cpu(pinstance->inq_data->fw_version);
+
+       spin_lock_irqsave(&pinstance->resource_lock, lock_flags);
+       list_for_each_entry_safe(res, temp, &pinstance->used_res_q, queue) {
+
+               if (res->change_detected == RES_CHANGE_DEL && res->scsi_dev) {
+                       sdev = res->scsi_dev;
+
+                       /* host_lock must be held before calling
+                        * scsi_device_get
+                        */
+                       spin_lock_irqsave(pinstance->host->host_lock,
+                                         host_lock_flags);
+                       if (!scsi_device_get(sdev)) {
+                               spin_unlock_irqrestore(
+                                               pinstance->host->host_lock,
+                                               host_lock_flags);
+                               pmcraid_info("deleting %x from midlayer\n",
+                                            res->cfg_entry.resource_address);
+                               list_move_tail(&res->queue,
+                                               &pinstance->free_res_q);
+                               spin_unlock_irqrestore(
+                                       &pinstance->resource_lock,
+                                       lock_flags);
+                               scsi_remove_device(sdev);
+                               scsi_device_put(sdev);
+                               spin_lock_irqsave(&pinstance->resource_lock,
+                                                  lock_flags);
+                               res->change_detected = 0;
+                       } else {
+                               spin_unlock_irqrestore(
+                                               pinstance->host->host_lock,
+                                               host_lock_flags);
+                       }
+               }
+       }
+
+       list_for_each_entry(res, &pinstance->used_res_q, queue) {
+
+               if (res->change_detected == RES_CHANGE_ADD) {
+
+                       if (!pmcraid_expose_resource(fw_version,
+                                                    &res->cfg_entry))
+                               continue;
+
+                       if (RES_IS_VSET(res->cfg_entry)) {
+                               bus = PMCRAID_VSET_BUS_ID;
+                               if (fw_version <= PMCRAID_FW_VERSION_1)
+                                       target = res->cfg_entry.unique_flags1;
+                               else
+                                       target = res->cfg_entry.array_id & 0xFF;
+                               lun = PMCRAID_VSET_LUN_ID;
+                       } else {
+                               bus = PMCRAID_PHYS_BUS_ID;
+                               target =
+                                    RES_TARGET(
+                                       res->cfg_entry.resource_address);
+                               lun = RES_LUN(res->cfg_entry.resource_address);
+                       }
+
+                       res->change_detected = 0;
+                       spin_unlock_irqrestore(&pinstance->resource_lock,
+                                               lock_flags);
+                       scsi_add_device(pinstance->host, bus, target, lun);
+                       spin_lock_irqsave(&pinstance->resource_lock,
+                                          lock_flags);
+               }
+       }
+
+       spin_unlock_irqrestore(&pinstance->resource_lock, lock_flags);
+}
+
+/**
+ * pmcraid_tasklet_function - Tasklet function
+ *
+ * @instance: pointer to msix param structure
+ *
+ * Return Value
+ *     None
+ */
+static void pmcraid_tasklet_function(unsigned long instance)
+{
+       struct pmcraid_isr_param *hrrq_vector;
+       struct pmcraid_instance *pinstance;
+       unsigned long hrrq_lock_flags;
+       unsigned long pending_lock_flags;
+       unsigned long host_lock_flags;
+       spinlock_t *lockp; /* hrrq buffer lock */
+       int id;
+       __le32 resp;
+
+       hrrq_vector = (struct pmcraid_isr_param *)instance;
+       pinstance = hrrq_vector->drv_inst;
+       id = hrrq_vector->hrrq_id;
+       lockp = &(pinstance->hrrq_lock[id]);
+
+       /* loop through each of the commands responded by IOA. Each HRRQ buf is
+        * protected by its own lock. Traversals must be done within this lock
+        * as there may be multiple tasklets running on multiple CPUs. Note
+        * that the lock is held just for picking up the response handle and
+        * manipulating hrrq_curr/toggle_bit values.
+        */
+       spin_lock_irqsave(lockp, hrrq_lock_flags);
+
+       resp = le32_to_cpu(*(pinstance->hrrq_curr[id]));
+
+       while ((resp & HRRQ_TOGGLE_BIT) ==
+               pinstance->host_toggle_bit[id]) {
+
+               int cmd_index = resp >> 2;
+               struct pmcraid_cmd *cmd = NULL;
+
+               if (pinstance->hrrq_curr[id] < pinstance->hrrq_end[id]) {
+                       pinstance->hrrq_curr[id]++;
+               } else {
+                       pinstance->hrrq_curr[id] = pinstance->hrrq_start[id];
+                       pinstance->host_toggle_bit[id] ^= 1u;
+               }
+
+               if (cmd_index >= PMCRAID_MAX_CMD) {
+                       /* In case of invalid response handle, log message */
+                       pmcraid_err("Invalid response handle %d\n", cmd_index);
+                       resp = le32_to_cpu(*(pinstance->hrrq_curr[id]));
+                       continue;
+               }
+
+               cmd = pinstance->cmd_list[cmd_index];
+               spin_unlock_irqrestore(lockp, hrrq_lock_flags);
+
+               spin_lock_irqsave(&pinstance->pending_pool_lock,
+                                  pending_lock_flags);
+               list_del(&cmd->free_list);
+               spin_unlock_irqrestore(&pinstance->pending_pool_lock,
+                                       pending_lock_flags);
+               del_timer(&cmd->timer);
+               atomic_dec(&pinstance->outstanding_cmds);
+
+               if (cmd->cmd_done == pmcraid_ioa_reset) {
+                       spin_lock_irqsave(pinstance->host->host_lock,
+                                         host_lock_flags);
+                       cmd->cmd_done(cmd);
+                       spin_unlock_irqrestore(pinstance->host->host_lock,
+                                              host_lock_flags);
+               } else if (cmd->cmd_done != NULL) {
+                       cmd->cmd_done(cmd);
+               }
+               /* loop over until we are done with all responses */
+               spin_lock_irqsave(lockp, hrrq_lock_flags);
+               resp = le32_to_cpu(*(pinstance->hrrq_curr[id]));
+       }
+
+       spin_unlock_irqrestore(lockp, hrrq_lock_flags);
+}
+
+/**
+ * pmcraid_unregister_interrupt_handler - de-register interrupts handlers
+ * @pinstance: pointer to adapter instance structure
+ *
+ * This routine un-registers registered interrupt handler and
+ * also frees irqs/vectors.
+ *
+ * Retun Value
+ *     None
+ */
+static
+void pmcraid_unregister_interrupt_handler(struct pmcraid_instance *pinstance)
+{
+       int i;
+
+       for (i = 0; i < pinstance->num_hrrq; i++)
+               free_irq(pinstance->hrrq_vector[i].vector,
+                        &(pinstance->hrrq_vector[i]));
+
+       if (pinstance->interrupt_mode) {
+               pci_disable_msix(pinstance->pdev);
+               pinstance->interrupt_mode = 0;
+       }
+}
+
+/**
+ * pmcraid_register_interrupt_handler - registers interrupt handler
+ * @pinstance: pointer to per-adapter instance structure
+ *
+ * Return Value
+ *     0 on success, non-zero error code otherwise.
+ */
+static int
+pmcraid_register_interrupt_handler(struct pmcraid_instance *pinstance)
+{
+       int rc;
+       struct pci_dev *pdev = pinstance->pdev;
+
+       if ((pmcraid_enable_msix) &&
+               (pci_find_capability(pdev, PCI_CAP_ID_MSIX))) {
+               int num_hrrq = PMCRAID_NUM_MSIX_VECTORS;
+               struct msix_entry entries[PMCRAID_NUM_MSIX_VECTORS];
+               int i;
+               for (i = 0; i < PMCRAID_NUM_MSIX_VECTORS; i++)
+                       entries[i].entry = i;
+
+               num_hrrq = pci_enable_msix_range(pdev, entries, 1, num_hrrq);
+               if (num_hrrq < 0)
+                       goto pmcraid_isr_legacy;
+
+               for (i = 0; i < num_hrrq; i++) {
+                       pinstance->hrrq_vector[i].hrrq_id = i;
+                       pinstance->hrrq_vector[i].drv_inst = pinstance;
+                       pinstance->hrrq_vector[i].vector = entries[i].vector;
+                       rc = request_irq(pinstance->hrrq_vector[i].vector,
+                                       pmcraid_isr_msix, 0,
+                                       PMCRAID_DRIVER_NAME,
+                                       &(pinstance->hrrq_vector[i]));
+
+                       if (rc) {
+                               int j;
+                               for (j = 0; j < i; j++)
+                                       free_irq(entries[j].vector,
+                                                &(pinstance->hrrq_vector[j]));
+                               pci_disable_msix(pdev);
+                               goto pmcraid_isr_legacy;
+                       }
+               }
+
+               pinstance->num_hrrq = num_hrrq;
+               pinstance->interrupt_mode = 1;
+               iowrite32(DOORBELL_INTR_MODE_MSIX,
+                         pinstance->int_regs.host_ioa_interrupt_reg);
+               ioread32(pinstance->int_regs.host_ioa_interrupt_reg);
+               goto pmcraid_isr_out;
+       }
+
+pmcraid_isr_legacy:
+       /* If MSI-X registration failed fallback to legacy mode, where
+        * only one hrrq entry will be used
+        */
+       pinstance->hrrq_vector[0].hrrq_id = 0;
+       pinstance->hrrq_vector[0].drv_inst = pinstance;
+       pinstance->hrrq_vector[0].vector = pdev->irq;
+       pinstance->num_hrrq = 1;
+
+       rc = request_irq(pdev->irq, pmcraid_isr, IRQF_SHARED,
+                        PMCRAID_DRIVER_NAME, &pinstance->hrrq_vector[0]);
+pmcraid_isr_out:
+       return rc;
+}
+
+/**
+ * pmcraid_release_cmd_blocks - release buufers allocated for command blocks
+ * @pinstance: per adapter instance structure pointer
+ * @max_index: number of buffer blocks to release
+ *
+ * Return Value
+ *  None
+ */
+static void
+pmcraid_release_cmd_blocks(struct pmcraid_instance *pinstance, int max_index)
+{
+       int i;
+       for (i = 0; i < max_index; i++) {
+               kmem_cache_free(pinstance->cmd_cachep, pinstance->cmd_list[i]);
+               pinstance->cmd_list[i] = NULL;
+       }
+       kmem_cache_destroy(pinstance->cmd_cachep);
+       pinstance->cmd_cachep = NULL;
+}
+
+/**
+ * pmcraid_release_control_blocks - releases buffers alloced for control blocks
+ * @pinstance: pointer to per adapter instance structure
+ * @max_index: number of buffers (from 0 onwards) to release
+ *
+ * This function assumes that the command blocks for which control blocks are
+ * linked are not released.
+ *
+ * Return Value
+ *      None
+ */
+static void
+pmcraid_release_control_blocks(
+       struct pmcraid_instance *pinstance,
+       int max_index
+)
+{
+       int i;
+
+       if (pinstance->control_pool == NULL)
+               return;
+
+       for (i = 0; i < max_index; i++) {
+               pci_pool_free(pinstance->control_pool,
+                             pinstance->cmd_list[i]->ioa_cb,
+                             pinstance->cmd_list[i]->ioa_cb_bus_addr);
+               pinstance->cmd_list[i]->ioa_cb = NULL;
+               pinstance->cmd_list[i]->ioa_cb_bus_addr = 0;
+       }
+       pci_pool_destroy(pinstance->control_pool);
+       pinstance->control_pool = NULL;
+}
+
+/**
+ * pmcraid_allocate_cmd_blocks - allocate memory for cmd block structures
+ * @pinstance - pointer to per adapter instance structure
+ *
+ * Allocates memory for command blocks using kernel slab allocator.
+ *
+ * Return Value
+ *     0 in case of success; -ENOMEM in case of failure
+ */
+static int pmcraid_allocate_cmd_blocks(struct pmcraid_instance *pinstance)
+{
+       int i;
+
+       sprintf(pinstance->cmd_pool_name, "pmcraid_cmd_pool_%d",
+               pinstance->host->unique_id);
+
+
+       pinstance->cmd_cachep = kmem_cache_create(
+                                       pinstance->cmd_pool_name,
+                                       sizeof(struct pmcraid_cmd), 0,
+                                       SLAB_HWCACHE_ALIGN, NULL);
+       if (!pinstance->cmd_cachep)
+               return -ENOMEM;
+
+       for (i = 0; i < PMCRAID_MAX_CMD; i++) {
+               pinstance->cmd_list[i] =
+                       kmem_cache_alloc(pinstance->cmd_cachep, GFP_KERNEL);
+               if (!pinstance->cmd_list[i]) {
+                       pmcraid_release_cmd_blocks(pinstance, i);
+                       return -ENOMEM;
+               }
+       }
+       return 0;
+}
+
+/**
+ * pmcraid_allocate_control_blocks - allocates memory control blocks
+ * @pinstance : pointer to per adapter instance structure
+ *
+ * This function allocates PCI memory for DMAable buffers like IOARCB, IOADLs
+ * and IOASAs. This is called after command blocks are already allocated.
+ *
+ * Return Value
+ *  0 in case it can allocate all control blocks, otherwise -ENOMEM
+ */
+static int pmcraid_allocate_control_blocks(struct pmcraid_instance *pinstance)
+{
+       int i;
+
+       sprintf(pinstance->ctl_pool_name, "pmcraid_control_pool_%d",
+               pinstance->host->unique_id);
+
+       pinstance->control_pool =
+               pci_pool_create(pinstance->ctl_pool_name,
+                               pinstance->pdev,
+                               sizeof(struct pmcraid_control_block),
+                               PMCRAID_IOARCB_ALIGNMENT, 0);
+
+       if (!pinstance->control_pool)
+               return -ENOMEM;
+
+       for (i = 0; i < PMCRAID_MAX_CMD; i++) {
+               pinstance->cmd_list[i]->ioa_cb =
+                       pci_pool_alloc(
+                               pinstance->control_pool,
+                               GFP_KERNEL,
+                               &(pinstance->cmd_list[i]->ioa_cb_bus_addr));
+
+               if (!pinstance->cmd_list[i]->ioa_cb) {
+                       pmcraid_release_control_blocks(pinstance, i);
+                       return -ENOMEM;
+               }
+               memset(pinstance->cmd_list[i]->ioa_cb, 0,
+                       sizeof(struct pmcraid_control_block));
+       }
+       return 0;
+}
+
+/**
+ * pmcraid_release_host_rrqs - release memory allocated for hrrq buffer(s)
+ * @pinstance: pointer to per adapter instance structure
+ * @maxindex: size of hrrq buffer pointer array
+ *
+ * Return Value
+ *     None
+ */
+static void
+pmcraid_release_host_rrqs(struct pmcraid_instance *pinstance, int maxindex)
+{
+       int i;
+       for (i = 0; i < maxindex; i++) {
+
+               pci_free_consistent(pinstance->pdev,
+                                   HRRQ_ENTRY_SIZE * PMCRAID_MAX_CMD,
+                                   pinstance->hrrq_start[i],
+                                   pinstance->hrrq_start_bus_addr[i]);
+
+               /* reset pointers and toggle bit to zeros */
+               pinstance->hrrq_start[i] = NULL;
+               pinstance->hrrq_start_bus_addr[i] = 0;
+               pinstance->host_toggle_bit[i] = 0;
+       }
+}
+
+/**
+ * pmcraid_allocate_host_rrqs - Allocate and initialize host RRQ buffers
+ * @pinstance: pointer to per adapter instance structure
+ *
+ * Return value
+ *     0 hrrq buffers are allocated, -ENOMEM otherwise.
+ */
+static int pmcraid_allocate_host_rrqs(struct pmcraid_instance *pinstance)
+{
+       int i, buffer_size;
+
+       buffer_size = HRRQ_ENTRY_SIZE * PMCRAID_MAX_CMD;
+
+       for (i = 0; i < pinstance->num_hrrq; i++) {
+               pinstance->hrrq_start[i] =
+                       pci_alloc_consistent(
+                                       pinstance->pdev,
+                                       buffer_size,
+                                       &(pinstance->hrrq_start_bus_addr[i]));
+
+               if (pinstance->hrrq_start[i] == 0) {
+                       pmcraid_err("pci_alloc failed for hrrq vector : %d\n",
+                                   i);
+                       pmcraid_release_host_rrqs(pinstance, i);
+                       return -ENOMEM;
+               }
+
+               memset(pinstance->hrrq_start[i], 0, buffer_size);
+               pinstance->hrrq_curr[i] = pinstance->hrrq_start[i];
+               pinstance->hrrq_end[i] =
+                       pinstance->hrrq_start[i] + PMCRAID_MAX_CMD - 1;
+               pinstance->host_toggle_bit[i] = 1;
+               spin_lock_init(&pinstance->hrrq_lock[i]);
+       }
+       return 0;
+}
+
+/**
+ * pmcraid_release_hcams - release HCAM buffers
+ *
+ * @pinstance: pointer to per adapter instance structure
+ *
+ * Return value
+ *  none
+ */
+static void pmcraid_release_hcams(struct pmcraid_instance *pinstance)
+{
+       if (pinstance->ccn.msg != NULL) {
+               pci_free_consistent(pinstance->pdev,
+                                   PMCRAID_AEN_HDR_SIZE +
+                                   sizeof(struct pmcraid_hcam_ccn_ext),
+                                   pinstance->ccn.msg,
+                                   pinstance->ccn.baddr);
+
+               pinstance->ccn.msg = NULL;
+               pinstance->ccn.hcam = NULL;
+               pinstance->ccn.baddr = 0;
+       }
+
+       if (pinstance->ldn.msg != NULL) {
+               pci_free_consistent(pinstance->pdev,
+                                   PMCRAID_AEN_HDR_SIZE +
+                                   sizeof(struct pmcraid_hcam_ldn),
+                                   pinstance->ldn.msg,
+                                   pinstance->ldn.baddr);
+
+               pinstance->ldn.msg = NULL;
+               pinstance->ldn.hcam = NULL;
+               pinstance->ldn.baddr = 0;
+       }
+}
+
+/**
+ * pmcraid_allocate_hcams - allocates HCAM buffers
+ * @pinstance : pointer to per adapter instance structure
+ *
+ * Return Value:
+ *   0 in case of successful allocation, non-zero otherwise
+ */
+static int pmcraid_allocate_hcams(struct pmcraid_instance *pinstance)
+{
+       pinstance->ccn.msg = pci_alloc_consistent(
+                                       pinstance->pdev,
+                                       PMCRAID_AEN_HDR_SIZE +
+                                       sizeof(struct pmcraid_hcam_ccn_ext),
+                                       &(pinstance->ccn.baddr));
+
+       pinstance->ldn.msg = pci_alloc_consistent(
+                                       pinstance->pdev,
+                                       PMCRAID_AEN_HDR_SIZE +
+                                       sizeof(struct pmcraid_hcam_ldn),
+                                       &(pinstance->ldn.baddr));
+
+       if (pinstance->ldn.msg == NULL || pinstance->ccn.msg == NULL) {
+               pmcraid_release_hcams(pinstance);
+       } else {
+               pinstance->ccn.hcam =
+                       (void *)pinstance->ccn.msg + PMCRAID_AEN_HDR_SIZE;
+               pinstance->ldn.hcam =
+                       (void *)pinstance->ldn.msg + PMCRAID_AEN_HDR_SIZE;
+
+               atomic_set(&pinstance->ccn.ignore, 0);
+               atomic_set(&pinstance->ldn.ignore, 0);
+       }
+
+       return (pinstance->ldn.msg == NULL) ? -ENOMEM : 0;
+}
+
+/**
+ * pmcraid_release_config_buffers - release config.table buffers
+ * @pinstance: pointer to per adapter instance structure
+ *
+ * Return Value
+ *      none
+ */
+static void pmcraid_release_config_buffers(struct pmcraid_instance *pinstance)
+{
+       if (pinstance->cfg_table != NULL &&
+           pinstance->cfg_table_bus_addr != 0) {
+               pci_free_consistent(pinstance->pdev,
+                                   sizeof(struct pmcraid_config_table),
+                                   pinstance->cfg_table,
+                                   pinstance->cfg_table_bus_addr);
+               pinstance->cfg_table = NULL;
+               pinstance->cfg_table_bus_addr = 0;
+       }
+
+       if (pinstance->res_entries != NULL) {
+               int i;
+
+               for (i = 0; i < PMCRAID_MAX_RESOURCES; i++)
+                       list_del(&pinstance->res_entries[i].queue);
+               kfree(pinstance->res_entries);
+               pinstance->res_entries = NULL;
+       }
+
+       pmcraid_release_hcams(pinstance);
+}
+
+/**
+ * pmcraid_allocate_config_buffers - allocates DMAable memory for config table
+ * @pinstance : pointer to per adapter instance structure
+ *
+ * Return Value
+ *     0 for successful allocation, -ENOMEM for any failure
+ */
+static int pmcraid_allocate_config_buffers(struct pmcraid_instance *pinstance)
+{
+       int i;
+
+       pinstance->res_entries =
+                       kzalloc(sizeof(struct pmcraid_resource_entry) *
+                               PMCRAID_MAX_RESOURCES, GFP_KERNEL);
+
+       if (NULL == pinstance->res_entries) {
+               pmcraid_err("failed to allocate memory for resource table\n");
+               return -ENOMEM;
+       }
+
+       for (i = 0; i < PMCRAID_MAX_RESOURCES; i++)
+               list_add_tail(&pinstance->res_entries[i].queue,
+                             &pinstance->free_res_q);
+
+       pinstance->cfg_table =
+               pci_alloc_consistent(pinstance->pdev,
+                                    sizeof(struct pmcraid_config_table),
+                                    &pinstance->cfg_table_bus_addr);
+
+       if (NULL == pinstance->cfg_table) {
+               pmcraid_err("couldn't alloc DMA memory for config table\n");
+               pmcraid_release_config_buffers(pinstance);
+               return -ENOMEM;
+       }
+
+       if (pmcraid_allocate_hcams(pinstance)) {
+               pmcraid_err("could not alloc DMA memory for HCAMS\n");
+               pmcraid_release_config_buffers(pinstance);
+               return -ENOMEM;
+       }
+
+       return 0;
+}
+
+/**
+ * pmcraid_init_tasklets - registers tasklets for response handling
+ *
+ * @pinstance: pointer adapter instance structure
+ *
+ * Return value
+ *     none
+ */
+static void pmcraid_init_tasklets(struct pmcraid_instance *pinstance)
+{
+       int i;
+       for (i = 0; i < pinstance->num_hrrq; i++)
+               tasklet_init(&pinstance->isr_tasklet[i],
+                            pmcraid_tasklet_function,
+                            (unsigned long)&pinstance->hrrq_vector[i]);
+}
+
+/**
+ * pmcraid_kill_tasklets - destroys tasklets registered for response handling
+ *
+ * @pinstance: pointer to adapter instance structure
+ *
+ * Return value
+ *     none
+ */
+static void pmcraid_kill_tasklets(struct pmcraid_instance *pinstance)
+{
+       int i;
+       for (i = 0; i < pinstance->num_hrrq; i++)
+               tasklet_kill(&pinstance->isr_tasklet[i]);
+}
+
+/**
+ * pmcraid_release_buffers - release per-adapter buffers allocated
+ *
+ * @pinstance: pointer to adapter soft state
+ *
+ * Return Value
+ *     none
+ */
+static void pmcraid_release_buffers(struct pmcraid_instance *pinstance)
+{
+       pmcraid_release_config_buffers(pinstance);
+       pmcraid_release_control_blocks(pinstance, PMCRAID_MAX_CMD);
+       pmcraid_release_cmd_blocks(pinstance, PMCRAID_MAX_CMD);
+       pmcraid_release_host_rrqs(pinstance, pinstance->num_hrrq);
+
+       if (pinstance->inq_data != NULL) {
+               pci_free_consistent(pinstance->pdev,
+                                   sizeof(struct pmcraid_inquiry_data),
+                                   pinstance->inq_data,
+                                   pinstance->inq_data_baddr);
+
+               pinstance->inq_data = NULL;
+               pinstance->inq_data_baddr = 0;
+       }
+
+       if (pinstance->timestamp_data != NULL) {
+               pci_free_consistent(pinstance->pdev,
+                                   sizeof(struct pmcraid_timestamp_data),
+                                   pinstance->timestamp_data,
+                                   pinstance->timestamp_data_baddr);
+
+               pinstance->timestamp_data = NULL;
+               pinstance->timestamp_data_baddr = 0;
+       }
+}
+
+/**
+ * pmcraid_init_buffers - allocates memory and initializes various structures
+ * @pinstance: pointer to per adapter instance structure
+ *
+ * This routine pre-allocates memory based on the type of block as below:
+ * cmdblocks(PMCRAID_MAX_CMD): kernel memory using kernel's slab_allocator,
+ * IOARCBs(PMCRAID_MAX_CMD)  : DMAable memory, using pci pool allocator
+ * config-table entries      : DMAable memory using pci_alloc_consistent
+ * HostRRQs                  : DMAable memory, using pci_alloc_consistent
+ *
+ * Return Value
+ *      0 in case all of the blocks are allocated, -ENOMEM otherwise.
+ */
+static int pmcraid_init_buffers(struct pmcraid_instance *pinstance)
+{
+       int i;
+
+       if (pmcraid_allocate_host_rrqs(pinstance)) {
+               pmcraid_err("couldn't allocate memory for %d host rrqs\n",
+                            pinstance->num_hrrq);
+               return -ENOMEM;
+       }
+
+       if (pmcraid_allocate_config_buffers(pinstance)) {
+               pmcraid_err("couldn't allocate memory for config buffers\n");
+               pmcraid_release_host_rrqs(pinstance, pinstance->num_hrrq);
+               return -ENOMEM;
+       }
+
+       if (pmcraid_allocate_cmd_blocks(pinstance)) {
+               pmcraid_err("couldn't allocate memory for cmd blocks\n");
+               pmcraid_release_config_buffers(pinstance);
+               pmcraid_release_host_rrqs(pinstance, pinstance->num_hrrq);
+               return -ENOMEM;
+       }
+
+       if (pmcraid_allocate_control_blocks(pinstance)) {
+               pmcraid_err("couldn't allocate memory control blocks\n");
+               pmcraid_release_config_buffers(pinstance);
+               pmcraid_release_cmd_blocks(pinstance, PMCRAID_MAX_CMD);
+               pmcraid_release_host_rrqs(pinstance, pinstance->num_hrrq);
+               return -ENOMEM;
+       }
+
+       /* allocate DMAable memory for page D0 INQUIRY buffer */
+       pinstance->inq_data = pci_alloc_consistent(
+                                       pinstance->pdev,
+                                       sizeof(struct pmcraid_inquiry_data),
+                                       &pinstance->inq_data_baddr);
+
+       if (pinstance->inq_data == NULL) {
+               pmcraid_err("couldn't allocate DMA memory for INQUIRY\n");
+               pmcraid_release_buffers(pinstance);
+               return -ENOMEM;
+       }
+
+       /* allocate DMAable memory for set timestamp data buffer */
+       pinstance->timestamp_data = pci_alloc_consistent(
+                                       pinstance->pdev,
+                                       sizeof(struct pmcraid_timestamp_data),
+                                       &pinstance->timestamp_data_baddr);
+
+       if (pinstance->timestamp_data == NULL) {
+               pmcraid_err("couldn't allocate DMA memory for \
+                               set time_stamp \n");
+               pmcraid_release_buffers(pinstance);
+               return -ENOMEM;
+       }
+
+
+       /* Initialize all the command blocks and add them to free pool. No
+        * need to lock (free_pool_lock) as this is done in initialization
+        * itself
+        */
+       for (i = 0; i < PMCRAID_MAX_CMD; i++) {
+               struct pmcraid_cmd *cmdp = pinstance->cmd_list[i];
+               pmcraid_init_cmdblk(cmdp, i);
+               cmdp->drv_inst = pinstance;
+               list_add_tail(&cmdp->free_list, &pinstance->free_cmd_pool);
+       }
+
+       return 0;
+}
+
+/**
+ * pmcraid_reinit_buffers - resets various buffer pointers
+ * @pinstance: pointer to adapter instance
+ * Return value
+ *     none
+ */
+static void pmcraid_reinit_buffers(struct pmcraid_instance *pinstance)
+{
+       int i;
+       int buffer_size = HRRQ_ENTRY_SIZE * PMCRAID_MAX_CMD;
+
+       for (i = 0; i < pinstance->num_hrrq; i++) {
+               memset(pinstance->hrrq_start[i], 0, buffer_size);
+               pinstance->hrrq_curr[i] = pinstance->hrrq_start[i];
+               pinstance->hrrq_end[i] =
+                       pinstance->hrrq_start[i] + PMCRAID_MAX_CMD - 1;
+               pinstance->host_toggle_bit[i] = 1;
+       }
+}
+
+/**
+ * pmcraid_init_instance - initialize per instance data structure
+ * @pdev: pointer to pci device structure
+ * @host: pointer to Scsi_Host structure
+ * @mapped_pci_addr: memory mapped IOA configuration registers
+ *
+ * Return Value
+ *      0 on success, non-zero in case of any failure
+ */
+static int pmcraid_init_instance(struct pci_dev *pdev, struct Scsi_Host *host,
+                                void __iomem *mapped_pci_addr)
+{
+       struct pmcraid_instance *pinstance =
+               (struct pmcraid_instance *)host->hostdata;
+
+       pinstance->host = host;
+       pinstance->pdev = pdev;
+
+       /* Initialize register addresses */
+       pinstance->mapped_dma_addr = mapped_pci_addr;
+
+       /* Initialize chip-specific details */
+       {
+               struct pmcraid_chip_details *chip_cfg = pinstance->chip_cfg;
+               struct pmcraid_interrupts *pint_regs = &pinstance->int_regs;
+
+               pinstance->ioarrin = mapped_pci_addr + chip_cfg->ioarrin;
+
+               pint_regs->ioa_host_interrupt_reg =
+                       mapped_pci_addr + chip_cfg->ioa_host_intr;
+               pint_regs->ioa_host_interrupt_clr_reg =
+                       mapped_pci_addr + chip_cfg->ioa_host_intr_clr;
+               pint_regs->ioa_host_msix_interrupt_reg =
+                       mapped_pci_addr + chip_cfg->ioa_host_msix_intr;
+               pint_regs->host_ioa_interrupt_reg =
+                       mapped_pci_addr + chip_cfg->host_ioa_intr;
+               pint_regs->host_ioa_interrupt_clr_reg =
+                       mapped_pci_addr + chip_cfg->host_ioa_intr_clr;
+
+               /* Current version of firmware exposes interrupt mask set
+                * and mask clr registers through memory mapped bar0.
+                */
+               pinstance->mailbox = mapped_pci_addr + chip_cfg->mailbox;
+               pinstance->ioa_status = mapped_pci_addr + chip_cfg->ioastatus;
+               pint_regs->ioa_host_interrupt_mask_reg =
+                       mapped_pci_addr + chip_cfg->ioa_host_mask;
+               pint_regs->ioa_host_interrupt_mask_clr_reg =
+                       mapped_pci_addr + chip_cfg->ioa_host_mask_clr;
+               pint_regs->global_interrupt_mask_reg =
+                       mapped_pci_addr + chip_cfg->global_intr_mask;
+       };
+
+       pinstance->ioa_reset_attempts = 0;
+       init_waitqueue_head(&pinstance->reset_wait_q);
+
+       atomic_set(&pinstance->outstanding_cmds, 0);
+       atomic_set(&pinstance->last_message_id, 0);
+       atomic_set(&pinstance->expose_resources, 0);
+
+       INIT_LIST_HEAD(&pinstance->free_res_q);
+       INIT_LIST_HEAD(&pinstance->used_res_q);
+       INIT_LIST_HEAD(&pinstance->free_cmd_pool);
+       INIT_LIST_HEAD(&pinstance->pending_cmd_pool);
+
+       spin_lock_init(&pinstance->free_pool_lock);
+       spin_lock_init(&pinstance->pending_pool_lock);
+       spin_lock_init(&pinstance->resource_lock);
+       mutex_init(&pinstance->aen_queue_lock);
+
+       /* Work-queue (Shared) for deferred processing error handling */
+       INIT_WORK(&pinstance->worker_q, pmcraid_worker_function);
+
+       /* Initialize the default log_level */
+       pinstance->current_log_level = pmcraid_log_level;
+
+       /* Setup variables required for reset engine */
+       pinstance->ioa_state = IOA_STATE_UNKNOWN;
+       pinstance->reset_cmd = NULL;
+       return 0;
+}
+
+/**
+ * pmcraid_shutdown - shutdown adapter controller.
+ * @pdev: pci device struct
+ *
+ * Issues an adapter shutdown to the card waits for its completion
+ *
+ * Return value
+ *       none
+ */
+static void pmcraid_shutdown(struct pci_dev *pdev)
+{
+       struct pmcraid_instance *pinstance = pci_get_drvdata(pdev);
+       pmcraid_reset_bringdown(pinstance);
+}
+
+
+/**
+ * pmcraid_get_minor - returns unused minor number from minor number bitmap
+ */
+static unsigned short pmcraid_get_minor(void)
+{
+       int minor;
+
+       minor = find_first_zero_bit(pmcraid_minor, sizeof(pmcraid_minor));
+       __set_bit(minor, pmcraid_minor);
+       return minor;
+}
+
+/**
+ * pmcraid_release_minor - releases given minor back to minor number bitmap
+ */
+static void pmcraid_release_minor(unsigned short minor)
+{
+       __clear_bit(minor, pmcraid_minor);
+}
+
+/**
+ * pmcraid_setup_chrdev - allocates a minor number and registers a char device
+ *
+ * @pinstance: pointer to adapter instance for which to register device
+ *
+ * Return value
+ *     0 in case of success, otherwise non-zero
+ */
+static int pmcraid_setup_chrdev(struct pmcraid_instance *pinstance)
+{
+       int minor;
+       int error;
+
+       minor = pmcraid_get_minor();
+       cdev_init(&pinstance->cdev, &pmcraid_fops);
+       pinstance->cdev.owner = THIS_MODULE;
+
+       error = cdev_add(&pinstance->cdev, MKDEV(pmcraid_major, minor), 1);
+
+       if (error)
+               pmcraid_release_minor(minor);
+       else
+               device_create(pmcraid_class, NULL, MKDEV(pmcraid_major, minor),
+                             NULL, "%s%u", PMCRAID_DEVFILE, minor);
+       return error;
+}
+
+/**
+ * pmcraid_release_chrdev - unregisters per-adapter management interface
+ *
+ * @pinstance: pointer to adapter instance structure
+ *
+ * Return value
+ *  none
+ */
+static void pmcraid_release_chrdev(struct pmcraid_instance *pinstance)
+{
+       pmcraid_release_minor(MINOR(pinstance->cdev.dev));
+       device_destroy(pmcraid_class,
+                      MKDEV(pmcraid_major, MINOR(pinstance->cdev.dev)));
+       cdev_del(&pinstance->cdev);
+}
+
+/**
+ * pmcraid_remove - IOA hot plug remove entry point
+ * @pdev: pci device struct
+ *
+ * Return value
+ *       none
+ */
+static void pmcraid_remove(struct pci_dev *pdev)
+{
+       struct pmcraid_instance *pinstance = pci_get_drvdata(pdev);
+
+       /* remove the management interface (/dev file) for this device */
+       pmcraid_release_chrdev(pinstance);
+
+       /* remove host template from scsi midlayer */
+       scsi_remove_host(pinstance->host);
+
+       /* block requests from mid-layer */
+       scsi_block_requests(pinstance->host);
+
+       /* initiate shutdown adapter */
+       pmcraid_shutdown(pdev);
+
+       pmcraid_disable_interrupts(pinstance, ~0);
+       flush_work(&pinstance->worker_q);
+
+       pmcraid_kill_tasklets(pinstance);
+       pmcraid_unregister_interrupt_handler(pinstance);
+       pmcraid_release_buffers(pinstance);
+       iounmap(pinstance->mapped_dma_addr);
+       pci_release_regions(pdev);
+       scsi_host_put(pinstance->host);
+       pci_disable_device(pdev);
+
+       return;
+}
+
+#ifdef CONFIG_PM
+/**
+ * pmcraid_suspend - driver suspend entry point for power management
+ * @pdev:   PCI device structure
+ * @state:  PCI power state to suspend routine
+ *
+ * Return Value - 0 always
+ */
+static int pmcraid_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+       struct pmcraid_instance *pinstance = pci_get_drvdata(pdev);
+
+       pmcraid_shutdown(pdev);
+       pmcraid_disable_interrupts(pinstance, ~0);
+       pmcraid_kill_tasklets(pinstance);
+       pci_set_drvdata(pinstance->pdev, pinstance);
+       pmcraid_unregister_interrupt_handler(pinstance);
+       pci_save_state(pdev);
+       pci_disable_device(pdev);
+       pci_set_power_state(pdev, pci_choose_state(pdev, state));
+
+       return 0;
+}
+
+/**
+ * pmcraid_resume - driver resume entry point PCI power management
+ * @pdev: PCI device structure
+ *
+ * Return Value - 0 in case of success. Error code in case of any failure
+ */
+static int pmcraid_resume(struct pci_dev *pdev)
+{
+       struct pmcraid_instance *pinstance = pci_get_drvdata(pdev);
+       struct Scsi_Host *host = pinstance->host;
+       int rc;
+
+       pci_set_power_state(pdev, PCI_D0);
+       pci_enable_wake(pdev, PCI_D0, 0);
+       pci_restore_state(pdev);
+
+       rc = pci_enable_device(pdev);
+
+       if (rc) {
+               dev_err(&pdev->dev, "resume: Enable device failed\n");
+               return rc;
+       }
+
+       pci_set_master(pdev);
+
+       if ((sizeof(dma_addr_t) == 4) ||
+            pci_set_dma_mask(pdev, DMA_BIT_MASK(64)))
+               rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+
+       if (rc == 0)
+               rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
+
+       if (rc != 0) {
+               dev_err(&pdev->dev, "resume: Failed to set PCI DMA mask\n");
+               goto disable_device;
+       }
+
+       pmcraid_disable_interrupts(pinstance, ~0);
+       atomic_set(&pinstance->outstanding_cmds, 0);
+       rc = pmcraid_register_interrupt_handler(pinstance);
+
+       if (rc) {
+               dev_err(&pdev->dev,
+                       "resume: couldn't register interrupt handlers\n");
+               rc = -ENODEV;
+               goto release_host;
+       }
+
+       pmcraid_init_tasklets(pinstance);
+       pmcraid_enable_interrupts(pinstance, PMCRAID_PCI_INTERRUPTS);
+
+       /* Start with hard reset sequence which brings up IOA to operational
+        * state as well as completes the reset sequence.
+        */
+       pinstance->ioa_hard_reset = 1;
+
+       /* Start IOA firmware initialization and bring card to Operational
+        * state.
+        */
+       if (pmcraid_reset_bringup(pinstance)) {
+               dev_err(&pdev->dev, "couldn't initialize IOA\n");
+               rc = -ENODEV;
+               goto release_tasklets;
+       }
+
+       return 0;
+
+release_tasklets:
+       pmcraid_disable_interrupts(pinstance, ~0);
+       pmcraid_kill_tasklets(pinstance);
+       pmcraid_unregister_interrupt_handler(pinstance);
+
+release_host:
+       scsi_host_put(host);
+
+disable_device:
+       pci_disable_device(pdev);
+
+       return rc;
+}
+
+#else
+
+#define pmcraid_suspend NULL
+#define pmcraid_resume  NULL
+
+#endif /* CONFIG_PM */
+
+/**
+ * pmcraid_complete_ioa_reset - Called by either timer or tasklet during
+ *                             completion of the ioa reset
+ * @cmd: pointer to reset command block
+ */
+static void pmcraid_complete_ioa_reset(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       unsigned long flags;
+
+       spin_lock_irqsave(pinstance->host->host_lock, flags);
+       pmcraid_ioa_reset(cmd);
+       spin_unlock_irqrestore(pinstance->host->host_lock, flags);
+       scsi_unblock_requests(pinstance->host);
+       schedule_work(&pinstance->worker_q);
+}
+
+/**
+ * pmcraid_set_supported_devs - sends SET SUPPORTED DEVICES to IOAFP
+ *
+ * @cmd: pointer to pmcraid_cmd structure
+ *
+ * Return Value
+ *  0 for success or non-zero for failure cases
+ */
+static void pmcraid_set_supported_devs(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
+       void (*cmd_done) (struct pmcraid_cmd *) = pmcraid_complete_ioa_reset;
+
+       pmcraid_reinit_cmdblk(cmd);
+
+       ioarcb->resource_handle = cpu_to_le32(PMCRAID_IOA_RES_HANDLE);
+       ioarcb->request_type = REQ_TYPE_IOACMD;
+       ioarcb->cdb[0] = PMCRAID_SET_SUPPORTED_DEVICES;
+       ioarcb->cdb[1] = ALL_DEVICES_SUPPORTED;
+
+       /* If this was called as part of resource table reinitialization due to
+        * lost CCN, it is enough to return the command block back to free pool
+        * as part of set_supported_devs completion function.
+        */
+       if (cmd->drv_inst->reinit_cfg_table) {
+               cmd->drv_inst->reinit_cfg_table = 0;
+               cmd->release = 1;
+               cmd_done = pmcraid_reinit_cfgtable_done;
+       }
+
+       /* we will be done with the reset sequence after set supported devices,
+        * setup the done function to return the command block back to free
+        * pool
+        */
+       pmcraid_send_cmd(cmd,
+                        cmd_done,
+                        PMCRAID_SET_SUP_DEV_TIMEOUT,
+                        pmcraid_timeout_handler);
+       return;
+}
+
+/**
+ * pmcraid_set_timestamp - set the timestamp to IOAFP
+ *
+ * @cmd: pointer to pmcraid_cmd structure
+ *
+ * Return Value
+ *  0 for success or non-zero for failure cases
+ */
+static void pmcraid_set_timestamp(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
+       __be32 time_stamp_len = cpu_to_be32(PMCRAID_TIMESTAMP_LEN);
+       struct pmcraid_ioadl_desc *ioadl = ioarcb->add_data.u.ioadl;
+
+       struct timeval tv;
+       __le64 timestamp;
+
+       do_gettimeofday(&tv);
+       timestamp = tv.tv_sec * 1000;
+
+       pinstance->timestamp_data->timestamp[0] = (__u8)(timestamp);
+       pinstance->timestamp_data->timestamp[1] = (__u8)((timestamp) >> 8);
+       pinstance->timestamp_data->timestamp[2] = (__u8)((timestamp) >> 16);
+       pinstance->timestamp_data->timestamp[3] = (__u8)((timestamp) >> 24);
+       pinstance->timestamp_data->timestamp[4] = (__u8)((timestamp) >> 32);
+       pinstance->timestamp_data->timestamp[5] = (__u8)((timestamp)  >> 40);
+
+       pmcraid_reinit_cmdblk(cmd);
+       ioarcb->request_type = REQ_TYPE_SCSI;
+       ioarcb->resource_handle = cpu_to_le32(PMCRAID_IOA_RES_HANDLE);
+       ioarcb->cdb[0] = PMCRAID_SCSI_SET_TIMESTAMP;
+       ioarcb->cdb[1] = PMCRAID_SCSI_SERVICE_ACTION;
+       memcpy(&(ioarcb->cdb[6]), &time_stamp_len, sizeof(time_stamp_len));
+
+       ioarcb->ioadl_bus_addr = cpu_to_le64((cmd->ioa_cb_bus_addr) +
+                                       offsetof(struct pmcraid_ioarcb,
+                                               add_data.u.ioadl[0]));
+       ioarcb->ioadl_length = cpu_to_le32(sizeof(struct pmcraid_ioadl_desc));
+       ioarcb->ioarcb_bus_addr &= ~(0x1FULL);
+
+       ioarcb->request_flags0 |= NO_LINK_DESCS;
+       ioarcb->request_flags0 |= TRANSFER_DIR_WRITE;
+       ioarcb->data_transfer_length =
+               cpu_to_le32(sizeof(struct pmcraid_timestamp_data));
+       ioadl = &(ioarcb->add_data.u.ioadl[0]);
+       ioadl->flags = IOADL_FLAGS_LAST_DESC;
+       ioadl->address = cpu_to_le64(pinstance->timestamp_data_baddr);
+       ioadl->data_len = cpu_to_le32(sizeof(struct pmcraid_timestamp_data));
+
+       if (!pinstance->timestamp_error) {
+               pinstance->timestamp_error = 0;
+               pmcraid_send_cmd(cmd, pmcraid_set_supported_devs,
+                        PMCRAID_INTERNAL_TIMEOUT, pmcraid_timeout_handler);
+       } else {
+               pmcraid_send_cmd(cmd, pmcraid_return_cmd,
+                        PMCRAID_INTERNAL_TIMEOUT, pmcraid_timeout_handler);
+               return;
+       }
+}
+
+
+/**
+ * pmcraid_init_res_table - Initialize the resource table
+ * @cmd:  pointer to pmcraid command struct
+ *
+ * This function looks through the existing resource table, comparing
+ * it with the config table. This function will take care of old/new
+ * devices and schedule adding/removing them from the mid-layer
+ * as appropriate.
+ *
+ * Return value
+ *      None
+ */
+static void pmcraid_init_res_table(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       struct pmcraid_resource_entry *res, *temp;
+       struct pmcraid_config_table_entry *cfgte;
+       unsigned long lock_flags;
+       int found, rc, i;
+       u16 fw_version;
+       LIST_HEAD(old_res);
+
+       if (pinstance->cfg_table->flags & MICROCODE_UPDATE_REQUIRED)
+               pmcraid_err("IOA requires microcode download\n");
+
+       fw_version = be16_to_cpu(pinstance->inq_data->fw_version);
+
+       /* resource list is protected by pinstance->resource_lock.
+        * init_res_table can be called from probe (user-thread) or runtime
+        * reset (timer/tasklet)
+        */
+       spin_lock_irqsave(&pinstance->resource_lock, lock_flags);
+
+       list_for_each_entry_safe(res, temp, &pinstance->used_res_q, queue)
+               list_move_tail(&res->queue, &old_res);
+
+       for (i = 0; i < pinstance->cfg_table->num_entries; i++) {
+               if (be16_to_cpu(pinstance->inq_data->fw_version) <=
+                                               PMCRAID_FW_VERSION_1)
+                       cfgte = &pinstance->cfg_table->entries[i];
+               else
+                       cfgte = (struct pmcraid_config_table_entry *)
+                                       &pinstance->cfg_table->entries_ext[i];
+
+               if (!pmcraid_expose_resource(fw_version, cfgte))
+                       continue;
+
+               found = 0;
+
+               /* If this entry was already detected and initialized */
+               list_for_each_entry_safe(res, temp, &old_res, queue) {
+
+                       rc = memcmp(&res->cfg_entry.resource_address,
+                                   &cfgte->resource_address,
+                                   sizeof(cfgte->resource_address));
+                       if (!rc) {
+                               list_move_tail(&res->queue,
+                                               &pinstance->used_res_q);
+                               found = 1;
+                               break;
+                       }
+               }
+
+               /* If this is new entry, initialize it and add it the queue */
+               if (!found) {
+
+                       if (list_empty(&pinstance->free_res_q)) {
+                               pmcraid_err("Too many devices attached\n");
+                               break;
+                       }
+
+                       found = 1;
+                       res = list_entry(pinstance->free_res_q.next,
+                                        struct pmcraid_resource_entry, queue);
+
+                       res->scsi_dev = NULL;
+                       res->change_detected = RES_CHANGE_ADD;
+                       res->reset_progress = 0;
+                       list_move_tail(&res->queue, &pinstance->used_res_q);
+               }
+
+               /* copy new configuration table entry details into driver
+                * maintained resource entry
+                */
+               if (found) {
+                       memcpy(&res->cfg_entry, cfgte,
+                                       pinstance->config_table_entry_size);
+                       pmcraid_info("New res type:%x, vset:%x, addr:%x:\n",
+                                res->cfg_entry.resource_type,
+                                (fw_version <= PMCRAID_FW_VERSION_1 ?
+                                       res->cfg_entry.unique_flags1 :
+                                               res->cfg_entry.array_id & 0xFF),
+                                le32_to_cpu(res->cfg_entry.resource_address));
+               }
+       }
+
+       /* Detect any deleted entries, mark them for deletion from mid-layer */
+       list_for_each_entry_safe(res, temp, &old_res, queue) {
+
+               if (res->scsi_dev) {
+                       res->change_detected = RES_CHANGE_DEL;
+                       res->cfg_entry.resource_handle =
+                               PMCRAID_INVALID_RES_HANDLE;
+                       list_move_tail(&res->queue, &pinstance->used_res_q);
+               } else {
+                       list_move_tail(&res->queue, &pinstance->free_res_q);
+               }
+       }
+
+       /* release the resource list lock */
+       spin_unlock_irqrestore(&pinstance->resource_lock, lock_flags);
+       pmcraid_set_timestamp(cmd);
+}
+
+/**
+ * pmcraid_querycfg - Send a Query IOA Config to the adapter.
+ * @cmd: pointer pmcraid_cmd struct
+ *
+ * This function sends a Query IOA Configuration command to the adapter to
+ * retrieve the IOA configuration table.
+ *
+ * Return value:
+ *     none
+ */
+static void pmcraid_querycfg(struct pmcraid_cmd *cmd)
+{
+       struct pmcraid_ioarcb *ioarcb = &cmd->ioa_cb->ioarcb;
+       struct pmcraid_ioadl_desc *ioadl = ioarcb->add_data.u.ioadl;
+       struct pmcraid_instance *pinstance = cmd->drv_inst;
+       int cfg_table_size = cpu_to_be32(sizeof(struct pmcraid_config_table));
+
+       if (be16_to_cpu(pinstance->inq_data->fw_version) <=
+                                       PMCRAID_FW_VERSION_1)
+               pinstance->config_table_entry_size =
+                       sizeof(struct pmcraid_config_table_entry);
+       else
+               pinstance->config_table_entry_size =
+                       sizeof(struct pmcraid_config_table_entry_ext);
+
+       ioarcb->request_type = REQ_TYPE_IOACMD;
+       ioarcb->resource_handle = cpu_to_le32(PMCRAID_IOA_RES_HANDLE);
+
+       ioarcb->cdb[0] = PMCRAID_QUERY_IOA_CONFIG;
+
+       /* firmware requires 4-byte length field, specified in B.E format */
+       memcpy(&(ioarcb->cdb[10]), &cfg_table_size, sizeof(cfg_table_size));
+
+       /* Since entire config table can be described by single IOADL, it can
+        * be part of IOARCB itself
+        */
+       ioarcb->ioadl_bus_addr = cpu_to_le64((cmd->ioa_cb_bus_addr) +
+                                       offsetof(struct pmcraid_ioarcb,
+                                               add_data.u.ioadl[0]));
+       ioarcb->ioadl_length = cpu_to_le32(sizeof(struct pmcraid_ioadl_desc));
+       ioarcb->ioarcb_bus_addr &= ~(0x1FULL);
+
+       ioarcb->request_flags0 |= NO_LINK_DESCS;
+       ioarcb->data_transfer_length =
+               cpu_to_le32(sizeof(struct pmcraid_config_table));
+
+       ioadl = &(ioarcb->add_data.u.ioadl[0]);
+       ioadl->flags = IOADL_FLAGS_LAST_DESC;
+       ioadl->address = cpu_to_le64(pinstance->cfg_table_bus_addr);
+       ioadl->data_len = cpu_to_le32(sizeof(struct pmcraid_config_table));
+
+       pmcraid_send_cmd(cmd, pmcraid_init_res_table,
+                        PMCRAID_INTERNAL_TIMEOUT, pmcraid_timeout_handler);
+}
+
+
+/**
+ * pmcraid_probe - PCI probe entry pointer for PMC MaxRAID controller driver
+ * @pdev: pointer to pci device structure
+ * @dev_id: pointer to device ids structure
+ *
+ * Return Value
+ *     returns 0 if the device is claimed and successfully configured.
+ *     returns non-zero error code in case of any failure
+ */
+static int pmcraid_probe(struct pci_dev *pdev,
+                        const struct pci_device_id *dev_id)
+{
+       struct pmcraid_instance *pinstance;
+       struct Scsi_Host *host;
+       void __iomem *mapped_pci_addr;
+       int rc = PCIBIOS_SUCCESSFUL;
+
+       if (atomic_read(&pmcraid_adapter_count) >= PMCRAID_MAX_ADAPTERS) {
+               pmcraid_err
+                       ("maximum number(%d) of supported adapters reached\n",
+                        atomic_read(&pmcraid_adapter_count));
+               return -ENOMEM;
+       }
+
+       atomic_inc(&pmcraid_adapter_count);
+       rc = pci_enable_device(pdev);
+
+       if (rc) {
+               dev_err(&pdev->dev, "Cannot enable adapter\n");
+               atomic_dec(&pmcraid_adapter_count);
+               return rc;
+       }
+
+       dev_info(&pdev->dev,
+               "Found new IOA(%x:%x), Total IOA count: %d\n",
+                pdev->vendor, pdev->device,
+                atomic_read(&pmcraid_adapter_count));
+
+       rc = pci_request_regions(pdev, PMCRAID_DRIVER_NAME);
+
+       if (rc < 0) {
+               dev_err(&pdev->dev,
+                       "Couldn't register memory range of registers\n");
+               goto out_disable_device;
+       }
+
+       mapped_pci_addr = pci_iomap(pdev, 0, 0);
+
+       if (!mapped_pci_addr) {
+               dev_err(&pdev->dev, "Couldn't map PCI registers memory\n");
+               rc = -ENOMEM;
+               goto out_release_regions;
+       }
+
+       pci_set_master(pdev);
+
+       /* Firmware requires the system bus address of IOARCB to be within
+        * 32-bit addressable range though it has 64-bit IOARRIN register.
+        * However, firmware supports 64-bit streaming DMA buffers, whereas
+        * coherent buffers are to be 32-bit. Since pci_alloc_consistent always
+        * returns memory within 4GB (if not, change this logic), coherent
+        * buffers are within firmware acceptable address ranges.
+        */
+       if ((sizeof(dma_addr_t) == 4) ||
+           pci_set_dma_mask(pdev, DMA_BIT_MASK(64)))
+               rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+
+       /* firmware expects 32-bit DMA addresses for IOARRIN register; set 32
+        * bit mask for pci_alloc_consistent to return addresses within 4GB
+        */
+       if (rc == 0)
+               rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
+
+       if (rc != 0) {
+               dev_err(&pdev->dev, "Failed to set PCI DMA mask\n");
+               goto cleanup_nomem;
+       }
+
+       host = scsi_host_alloc(&pmcraid_host_template,
+                               sizeof(struct pmcraid_instance));
+
+       if (!host) {
+               dev_err(&pdev->dev, "scsi_host_alloc failed!\n");
+               rc = -ENOMEM;
+               goto cleanup_nomem;
+       }
+
+       host->max_id = PMCRAID_MAX_NUM_TARGETS_PER_BUS;
+       host->max_lun = PMCRAID_MAX_NUM_LUNS_PER_TARGET;
+       host->unique_id = host->host_no;
+       host->max_channel = PMCRAID_MAX_BUS_TO_SCAN;
+       host->max_cmd_len = PMCRAID_MAX_CDB_LEN;
+
+       /* zero out entire instance structure */
+       pinstance = (struct pmcraid_instance *)host->hostdata;
+       memset(pinstance, 0, sizeof(*pinstance));
+
+       pinstance->chip_cfg =
+               (struct pmcraid_chip_details *)(dev_id->driver_data);
+
+       rc = pmcraid_init_instance(pdev, host, mapped_pci_addr);
+
+       if (rc < 0) {
+               dev_err(&pdev->dev, "failed to initialize adapter instance\n");
+               goto out_scsi_host_put;
+       }
+
+       pci_set_drvdata(pdev, pinstance);
+
+       /* Save PCI config-space for use following the reset */
+       rc = pci_save_state(pinstance->pdev);
+
+       if (rc != 0) {
+               dev_err(&pdev->dev, "Failed to save PCI config space\n");
+               goto out_scsi_host_put;
+       }
+
+       pmcraid_disable_interrupts(pinstance, ~0);
+
+       rc = pmcraid_register_interrupt_handler(pinstance);
+
+       if (rc) {
+               dev_err(&pdev->dev, "couldn't register interrupt handler\n");
+               goto out_scsi_host_put;
+       }
+
+       pmcraid_init_tasklets(pinstance);
+
+       /* allocate verious buffers used by LLD.*/
+       rc = pmcraid_init_buffers(pinstance);
+
+       if (rc) {
+               pmcraid_err("couldn't allocate memory blocks\n");
+               goto out_unregister_isr;
+       }
+
+       /* check the reset type required */
+       pmcraid_reset_type(pinstance);
+
+       pmcraid_enable_interrupts(pinstance, PMCRAID_PCI_INTERRUPTS);
+
+       /* Start IOA firmware initialization and bring card to Operational
+        * state.
+        */
+       pmcraid_info("starting IOA initialization sequence\n");
+       if (pmcraid_reset_bringup(pinstance)) {
+               dev_err(&pdev->dev, "couldn't initialize IOA\n");
+               rc = 1;
+               goto out_release_bufs;
+       }
+
+       /* Add adapter instance into mid-layer list */
+       rc = scsi_add_host(pinstance->host, &pdev->dev);
+       if (rc != 0) {
+               pmcraid_err("couldn't add host into mid-layer: %d\n", rc);
+               goto out_release_bufs;
+       }
+
+       scsi_scan_host(pinstance->host);
+
+       rc = pmcraid_setup_chrdev(pinstance);
+
+       if (rc != 0) {
+               pmcraid_err("couldn't create mgmt interface, error: %x\n",
+                            rc);
+               goto out_remove_host;
+       }
+
+       /* Schedule worker thread to handle CCN and take care of adding and
+        * removing devices to OS
+        */
+       atomic_set(&pinstance->expose_resources, 1);
+       schedule_work(&pinstance->worker_q);
+       return rc;
+
+out_remove_host:
+       scsi_remove_host(host);
+
+out_release_bufs:
+       pmcraid_release_buffers(pinstance);
+
+out_unregister_isr:
+       pmcraid_kill_tasklets(pinstance);
+       pmcraid_unregister_interrupt_handler(pinstance);
+
+out_scsi_host_put:
+       scsi_host_put(host);
+
+cleanup_nomem:
+       iounmap(mapped_pci_addr);
+
+out_release_regions:
+       pci_release_regions(pdev);
+
+out_disable_device:
+       atomic_dec(&pmcraid_adapter_count);
+       pci_disable_device(pdev);
+       return -ENODEV;
+}
+
+/*
+ * PCI driver structure of pcmraid driver
+ */
+static struct pci_driver pmcraid_driver = {
+       .name = PMCRAID_DRIVER_NAME,
+       .id_table = pmcraid_pci_table,
+       .probe = pmcraid_probe,
+       .remove = pmcraid_remove,
+       .suspend = pmcraid_suspend,
+       .resume = pmcraid_resume,
+       .shutdown = pmcraid_shutdown
+};
+
+/**
+ * pmcraid_init - module load entry point
+ */
+static int __init pmcraid_init(void)
+{
+       dev_t dev;
+       int error;
+
+       pmcraid_info("%s Device Driver version: %s\n",
+                        PMCRAID_DRIVER_NAME, PMCRAID_DRIVER_VERSION);
+
+       error = alloc_chrdev_region(&dev, 0,
+                                   PMCRAID_MAX_ADAPTERS,
+                                   PMCRAID_DEVFILE);
+
+       if (error) {
+               pmcraid_err("failed to get a major number for adapters\n");
+               goto out_init;
+       }
+
+       pmcraid_major = MAJOR(dev);
+       pmcraid_class = class_create(THIS_MODULE, PMCRAID_DEVFILE);
+
+       if (IS_ERR(pmcraid_class)) {
+               error = PTR_ERR(pmcraid_class);
+               pmcraid_err("failed to register with sysfs, error = %x\n",
+                           error);
+               goto out_unreg_chrdev;
+       }
+
+       error = pmcraid_netlink_init();
+
+       if (error)
+               goto out_unreg_chrdev;
+
+       error = pci_register_driver(&pmcraid_driver);
+
+       if (error == 0)
+               goto out_init;
+
+       pmcraid_err("failed to register pmcraid driver, error = %x\n",
+                    error);
+       class_destroy(pmcraid_class);
+       pmcraid_netlink_release();
+
+out_unreg_chrdev:
+       unregister_chrdev_region(MKDEV(pmcraid_major, 0), PMCRAID_MAX_ADAPTERS);
+
+out_init:
+       return error;
+}
+
+/**
+ * pmcraid_exit - module unload entry point
+ */
+static void __exit pmcraid_exit(void)
+{
+       pmcraid_netlink_release();
+       unregister_chrdev_region(MKDEV(pmcraid_major, 0),
+                                PMCRAID_MAX_ADAPTERS);
+       pci_unregister_driver(&pmcraid_driver);
+       class_destroy(pmcraid_class);
+}
+
+module_init(pmcraid_init);
+module_exit(pmcraid_exit);