Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / scsi / fnic / fnic_trace.c
diff --git a/kernel/drivers/scsi/fnic/fnic_trace.c b/kernel/drivers/scsi/fnic/fnic_trace.c
new file mode 100644 (file)
index 0000000..65a9bde
--- /dev/null
@@ -0,0 +1,779 @@
+/*
+ * Copyright 2012 Cisco Systems, Inc.  All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/module.h>
+#include <linux/mempool.h>
+#include <linux/errno.h>
+#include <linux/spinlock.h>
+#include <linux/kallsyms.h>
+#include <linux/time.h>
+#include "fnic_io.h"
+#include "fnic.h"
+
+unsigned int trace_max_pages;
+static int fnic_max_trace_entries;
+
+static unsigned long fnic_trace_buf_p;
+static DEFINE_SPINLOCK(fnic_trace_lock);
+
+static fnic_trace_dbg_t fnic_trace_entries;
+int fnic_tracing_enabled = 1;
+
+/* static char *fnic_fc_ctlr_trace_buf_p; */
+
+static int fc_trace_max_entries;
+static unsigned long fnic_fc_ctlr_trace_buf_p;
+static fnic_trace_dbg_t fc_trace_entries;
+int fnic_fc_tracing_enabled = 1;
+int fnic_fc_trace_cleared = 1;
+static DEFINE_SPINLOCK(fnic_fc_trace_lock);
+
+
+/*
+ * fnic_trace_get_buf - Give buffer pointer to user to fill up trace information
+ *
+ * Description:
+ * This routine gets next available trace buffer entry location @wr_idx
+ * from allocated trace buffer pages and give that memory location
+ * to user to store the trace information.
+ *
+ * Return Value:
+ * This routine returns pointer to next available trace entry
+ * @fnic_buf_head for user to fill trace information.
+ */
+fnic_trace_data_t *fnic_trace_get_buf(void)
+{
+       unsigned long fnic_buf_head;
+       unsigned long flags;
+
+       spin_lock_irqsave(&fnic_trace_lock, flags);
+
+       /*
+        * Get next available memory location for writing trace information
+        * at @wr_idx and increment @wr_idx
+        */
+       fnic_buf_head =
+               fnic_trace_entries.page_offset[fnic_trace_entries.wr_idx];
+       fnic_trace_entries.wr_idx++;
+
+       /*
+        * Verify if trace buffer is full then change wd_idx to
+        * start from zero
+        */
+       if (fnic_trace_entries.wr_idx >= fnic_max_trace_entries)
+               fnic_trace_entries.wr_idx = 0;
+
+       /*
+        * Verify if write index @wr_idx and read index @rd_idx are same then
+        * increment @rd_idx to move to next entry in trace buffer
+        */
+       if (fnic_trace_entries.wr_idx == fnic_trace_entries.rd_idx) {
+               fnic_trace_entries.rd_idx++;
+               if (fnic_trace_entries.rd_idx >= fnic_max_trace_entries)
+                       fnic_trace_entries.rd_idx = 0;
+       }
+       spin_unlock_irqrestore(&fnic_trace_lock, flags);
+       return (fnic_trace_data_t *)fnic_buf_head;
+}
+
+/*
+ * fnic_get_trace_data - Copy trace buffer to a memory file
+ * @fnic_dbgfs_t: pointer to debugfs trace buffer
+ *
+ * Description:
+ * This routine gathers the fnic trace debugfs data from the fnic_trace_data_t
+ * buffer and dumps it to fnic_dbgfs_t. It will start at the rd_idx entry in
+ * the log and process the log until the end of the buffer. Then it will gather
+ * from the beginning of the log and process until the current entry @wr_idx.
+ *
+ * Return Value:
+ * This routine returns the amount of bytes that were dumped into fnic_dbgfs_t
+ */
+int fnic_get_trace_data(fnic_dbgfs_t *fnic_dbgfs_prt)
+{
+       int rd_idx;
+       int wr_idx;
+       int len = 0;
+       unsigned long flags;
+       char str[KSYM_SYMBOL_LEN];
+       struct timespec val;
+       fnic_trace_data_t *tbp;
+
+       spin_lock_irqsave(&fnic_trace_lock, flags);
+       rd_idx = fnic_trace_entries.rd_idx;
+       wr_idx = fnic_trace_entries.wr_idx;
+       if (wr_idx < rd_idx) {
+               while (1) {
+                       /* Start from read index @rd_idx */
+                       tbp = (fnic_trace_data_t *)
+                                 fnic_trace_entries.page_offset[rd_idx];
+                       if (!tbp) {
+                               spin_unlock_irqrestore(&fnic_trace_lock, flags);
+                               return 0;
+                       }
+                       /* Convert function pointer to function name */
+                       if (sizeof(unsigned long) < 8) {
+                               sprint_symbol(str, tbp->fnaddr.low);
+                               jiffies_to_timespec(tbp->timestamp.low, &val);
+                       } else {
+                               sprint_symbol(str, tbp->fnaddr.val);
+                               jiffies_to_timespec(tbp->timestamp.val, &val);
+                       }
+                       /*
+                        * Dump trace buffer entry to memory file
+                        * and increment read index @rd_idx
+                        */
+                       len += snprintf(fnic_dbgfs_prt->buffer + len,
+                                 (trace_max_pages * PAGE_SIZE * 3) - len,
+                                 "%16lu.%16lu %-50s %8x %8x %16llx %16llx "
+                                 "%16llx %16llx %16llx\n", val.tv_sec,
+                                 val.tv_nsec, str, tbp->host_no, tbp->tag,
+                                 tbp->data[0], tbp->data[1], tbp->data[2],
+                                 tbp->data[3], tbp->data[4]);
+                       rd_idx++;
+                       /*
+                        * If rd_idx is reached to maximum trace entries
+                        * then move rd_idx to zero
+                        */
+                       if (rd_idx > (fnic_max_trace_entries-1))
+                               rd_idx = 0;
+                       /*
+                        * Continure dumpping trace buffer entries into
+                        * memory file till rd_idx reaches write index
+                        */
+                       if (rd_idx == wr_idx)
+                               break;
+               }
+       } else if (wr_idx > rd_idx) {
+               while (1) {
+                       /* Start from read index @rd_idx */
+                       tbp = (fnic_trace_data_t *)
+                                 fnic_trace_entries.page_offset[rd_idx];
+                       if (!tbp) {
+                               spin_unlock_irqrestore(&fnic_trace_lock, flags);
+                               return 0;
+                       }
+                       /* Convert function pointer to function name */
+                       if (sizeof(unsigned long) < 8) {
+                               sprint_symbol(str, tbp->fnaddr.low);
+                               jiffies_to_timespec(tbp->timestamp.low, &val);
+                       } else {
+                               sprint_symbol(str, tbp->fnaddr.val);
+                               jiffies_to_timespec(tbp->timestamp.val, &val);
+                       }
+                       /*
+                        * Dump trace buffer entry to memory file
+                        * and increment read index @rd_idx
+                        */
+                       len += snprintf(fnic_dbgfs_prt->buffer + len,
+                                 (trace_max_pages * PAGE_SIZE * 3) - len,
+                                 "%16lu.%16lu %-50s %8x %8x %16llx %16llx "
+                                 "%16llx %16llx %16llx\n", val.tv_sec,
+                                 val.tv_nsec, str, tbp->host_no, tbp->tag,
+                                 tbp->data[0], tbp->data[1], tbp->data[2],
+                                 tbp->data[3], tbp->data[4]);
+                       rd_idx++;
+                       /*
+                        * Continue dumpping trace buffer entries into
+                        * memory file till rd_idx reaches write index
+                        */
+                       if (rd_idx == wr_idx)
+                               break;
+               }
+       }
+       spin_unlock_irqrestore(&fnic_trace_lock, flags);
+       return len;
+}
+
+/*
+ * fnic_get_stats_data - Copy fnic stats buffer to a memory file
+ * @fnic_dbgfs_t: pointer to debugfs fnic stats buffer
+ *
+ * Description:
+ * This routine gathers the fnic stats debugfs data from the fnic_stats struct
+ * and dumps it to stats_debug_info.
+ *
+ * Return Value:
+ * This routine returns the amount of bytes that were dumped into
+ * stats_debug_info
+ */
+int fnic_get_stats_data(struct stats_debug_info *debug,
+                       struct fnic_stats *stats)
+{
+       int len = 0;
+       int buf_size = debug->buf_size;
+       struct timespec val1, val2;
+
+       len = snprintf(debug->debug_buffer + len, buf_size - len,
+                 "------------------------------------------\n"
+                 "\t\tIO Statistics\n"
+                 "------------------------------------------\n");
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "Number of Active IOs: %lld\nMaximum Active IOs: %lld\n"
+                 "Number of IOs: %lld\nNumber of IO Completions: %lld\n"
+                 "Number of IO Failures: %lld\nNumber of IO NOT Found: %lld\n"
+                 "Number of Memory alloc Failures: %lld\n"
+                 "Number of IOREQ Null: %lld\n"
+                 "Number of SCSI cmd pointer Null: %lld\n",
+                 (u64)atomic64_read(&stats->io_stats.active_ios),
+                 (u64)atomic64_read(&stats->io_stats.max_active_ios),
+                 (u64)atomic64_read(&stats->io_stats.num_ios),
+                 (u64)atomic64_read(&stats->io_stats.io_completions),
+                 (u64)atomic64_read(&stats->io_stats.io_failures),
+                 (u64)atomic64_read(&stats->io_stats.io_not_found),
+                 (u64)atomic64_read(&stats->io_stats.alloc_failures),
+                 (u64)atomic64_read(&stats->io_stats.ioreq_null),
+                 (u64)atomic64_read(&stats->io_stats.sc_null));
+
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "\n------------------------------------------\n"
+                 "\t\tAbort Statistics\n"
+                 "------------------------------------------\n");
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "Number of Aborts: %lld\n"
+                 "Number of Abort Failures: %lld\n"
+                 "Number of Abort Driver Timeouts: %lld\n"
+                 "Number of Abort FW Timeouts: %lld\n"
+                 "Number of Abort IO NOT Found: %lld\n",
+                 (u64)atomic64_read(&stats->abts_stats.aborts),
+                 (u64)atomic64_read(&stats->abts_stats.abort_failures),
+                 (u64)atomic64_read(&stats->abts_stats.abort_drv_timeouts),
+                 (u64)atomic64_read(&stats->abts_stats.abort_fw_timeouts),
+                 (u64)atomic64_read(&stats->abts_stats.abort_io_not_found));
+
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "\n------------------------------------------\n"
+                 "\t\tTerminate Statistics\n"
+                 "------------------------------------------\n");
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "Number of Terminates: %lld\n"
+                 "Maximum Terminates: %lld\n"
+                 "Number of Terminate Driver Timeouts: %lld\n"
+                 "Number of Terminate FW Timeouts: %lld\n"
+                 "Number of Terminate IO NOT Found: %lld\n"
+                 "Number of Terminate Failures: %lld\n",
+                 (u64)atomic64_read(&stats->term_stats.terminates),
+                 (u64)atomic64_read(&stats->term_stats.max_terminates),
+                 (u64)atomic64_read(&stats->term_stats.terminate_drv_timeouts),
+                 (u64)atomic64_read(&stats->term_stats.terminate_fw_timeouts),
+                 (u64)atomic64_read(&stats->term_stats.terminate_io_not_found),
+                 (u64)atomic64_read(&stats->term_stats.terminate_failures));
+
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "\n------------------------------------------\n"
+                 "\t\tReset Statistics\n"
+                 "------------------------------------------\n");
+
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "Number of Device Resets: %lld\n"
+                 "Number of Device Reset Failures: %lld\n"
+                 "Number of Device Reset Aborts: %lld\n"
+                 "Number of Device Reset Timeouts: %lld\n"
+                 "Number of Device Reset Terminates: %lld\n"
+                 "Number of FW Resets: %lld\n"
+                 "Number of FW Reset Completions: %lld\n"
+                 "Number of FW Reset Failures: %lld\n"
+                 "Number of Fnic Reset: %lld\n"
+                 "Number of Fnic Reset Completions: %lld\n"
+                 "Number of Fnic Reset Failures: %lld\n",
+                 (u64)atomic64_read(&stats->reset_stats.device_resets),
+                 (u64)atomic64_read(&stats->reset_stats.device_reset_failures),
+                 (u64)atomic64_read(&stats->reset_stats.device_reset_aborts),
+                 (u64)atomic64_read(&stats->reset_stats.device_reset_timeouts),
+                 (u64)atomic64_read(
+                         &stats->reset_stats.device_reset_terminates),
+                 (u64)atomic64_read(&stats->reset_stats.fw_resets),
+                 (u64)atomic64_read(&stats->reset_stats.fw_reset_completions),
+                 (u64)atomic64_read(&stats->reset_stats.fw_reset_failures),
+                 (u64)atomic64_read(&stats->reset_stats.fnic_resets),
+                 (u64)atomic64_read(
+                         &stats->reset_stats.fnic_reset_completions),
+                 (u64)atomic64_read(&stats->reset_stats.fnic_reset_failures));
+
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "\n------------------------------------------\n"
+                 "\t\tFirmware Statistics\n"
+                 "------------------------------------------\n");
+
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "Number of Active FW Requests %lld\n"
+                 "Maximum FW Requests: %lld\n"
+                 "Number of FW out of resources: %lld\n"
+                 "Number of FW IO errors: %lld\n",
+                 (u64)atomic64_read(&stats->fw_stats.active_fw_reqs),
+                 (u64)atomic64_read(&stats->fw_stats.max_fw_reqs),
+                 (u64)atomic64_read(&stats->fw_stats.fw_out_of_resources),
+                 (u64)atomic64_read(&stats->fw_stats.io_fw_errs));
+
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "\n------------------------------------------\n"
+                 "\t\tVlan Discovery Statistics\n"
+                 "------------------------------------------\n");
+
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "Number of Vlan Discovery Requests Sent %lld\n"
+                 "Vlan Response Received with no FCF VLAN ID: %lld\n"
+                 "No solicitations recvd after vlan set, expiry count: %lld\n"
+                 "Flogi rejects count: %lld\n",
+                 (u64)atomic64_read(&stats->vlan_stats.vlan_disc_reqs),
+                 (u64)atomic64_read(&stats->vlan_stats.resp_withno_vlanID),
+                 (u64)atomic64_read(&stats->vlan_stats.sol_expiry_count),
+                 (u64)atomic64_read(&stats->vlan_stats.flogi_rejects));
+
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "\n------------------------------------------\n"
+                 "\t\tOther Important Statistics\n"
+                 "------------------------------------------\n");
+
+       jiffies_to_timespec(stats->misc_stats.last_isr_time, &val1);
+       jiffies_to_timespec(stats->misc_stats.last_ack_time, &val2);
+
+       len += snprintf(debug->debug_buffer + len, buf_size - len,
+                 "Last ISR time: %llu (%8lu.%8lu)\n"
+                 "Last ACK time: %llu (%8lu.%8lu)\n"
+                 "Number of ISRs: %lld\n"
+                 "Maximum CQ Entries: %lld\n"
+                 "Number of ACK index out of range: %lld\n"
+                 "Number of data count mismatch: %lld\n"
+                 "Number of FCPIO Timeouts: %lld\n"
+                 "Number of FCPIO Aborted: %lld\n"
+                 "Number of SGL Invalid: %lld\n"
+                 "Number of Copy WQ Alloc Failures for ABTs: %lld\n"
+                 "Number of Copy WQ Alloc Failures for Device Reset: %lld\n"
+                 "Number of Copy WQ Alloc Failures for IOs: %lld\n"
+                 "Number of no icmnd itmf Completions: %lld\n"
+                 "Number of QUEUE Fulls: %lld\n"
+                 "Number of rport not ready: %lld\n"
+                 "Number of receive frame errors: %lld\n",
+                 (u64)stats->misc_stats.last_isr_time,
+                 val1.tv_sec, val1.tv_nsec,
+                 (u64)stats->misc_stats.last_ack_time,
+                 val2.tv_sec, val2.tv_nsec,
+                 (u64)atomic64_read(&stats->misc_stats.isr_count),
+                 (u64)atomic64_read(&stats->misc_stats.max_cq_entries),
+                 (u64)atomic64_read(&stats->misc_stats.ack_index_out_of_range),
+                 (u64)atomic64_read(&stats->misc_stats.data_count_mismatch),
+                 (u64)atomic64_read(&stats->misc_stats.fcpio_timeout),
+                 (u64)atomic64_read(&stats->misc_stats.fcpio_aborted),
+                 (u64)atomic64_read(&stats->misc_stats.sgl_invalid),
+                 (u64)atomic64_read(
+                         &stats->misc_stats.abts_cpwq_alloc_failures),
+                 (u64)atomic64_read(
+                         &stats->misc_stats.devrst_cpwq_alloc_failures),
+                 (u64)atomic64_read(&stats->misc_stats.io_cpwq_alloc_failures),
+                 (u64)atomic64_read(&stats->misc_stats.no_icmnd_itmf_cmpls),
+                 (u64)atomic64_read(&stats->misc_stats.queue_fulls),
+                 (u64)atomic64_read(&stats->misc_stats.rport_not_ready),
+                 (u64)atomic64_read(&stats->misc_stats.frame_errors));
+
+       return len;
+
+}
+
+/*
+ * fnic_trace_buf_init - Initialize fnic trace buffer logging facility
+ *
+ * Description:
+ * Initialize trace buffer data structure by allocating required memory and
+ * setting page_offset information for every trace entry by adding trace entry
+ * length to previous page_offset value.
+ */
+int fnic_trace_buf_init(void)
+{
+       unsigned long fnic_buf_head;
+       int i;
+       int err = 0;
+
+       trace_max_pages = fnic_trace_max_pages;
+       fnic_max_trace_entries = (trace_max_pages * PAGE_SIZE)/
+                                         FNIC_ENTRY_SIZE_BYTES;
+
+       fnic_trace_buf_p = (unsigned long)vmalloc((trace_max_pages * PAGE_SIZE));
+       if (!fnic_trace_buf_p) {
+               printk(KERN_ERR PFX "Failed to allocate memory "
+                                 "for fnic_trace_buf_p\n");
+               err = -ENOMEM;
+               goto err_fnic_trace_buf_init;
+       }
+       memset((void *)fnic_trace_buf_p, 0, (trace_max_pages * PAGE_SIZE));
+
+       fnic_trace_entries.page_offset = vmalloc(fnic_max_trace_entries *
+                                                 sizeof(unsigned long));
+       if (!fnic_trace_entries.page_offset) {
+               printk(KERN_ERR PFX "Failed to allocate memory for"
+                                 " page_offset\n");
+               if (fnic_trace_buf_p) {
+                       vfree((void *)fnic_trace_buf_p);
+                       fnic_trace_buf_p = 0;
+               }
+               err = -ENOMEM;
+               goto err_fnic_trace_buf_init;
+       }
+       memset((void *)fnic_trace_entries.page_offset, 0,
+                 (fnic_max_trace_entries * sizeof(unsigned long)));
+       fnic_trace_entries.wr_idx = fnic_trace_entries.rd_idx = 0;
+       fnic_buf_head = fnic_trace_buf_p;
+
+       /*
+        * Set page_offset field of fnic_trace_entries struct by
+        * calculating memory location for every trace entry using
+        * length of each trace entry
+        */
+       for (i = 0; i < fnic_max_trace_entries; i++) {
+               fnic_trace_entries.page_offset[i] = fnic_buf_head;
+               fnic_buf_head += FNIC_ENTRY_SIZE_BYTES;
+       }
+       err = fnic_trace_debugfs_init();
+       if (err < 0) {
+               pr_err("fnic: Failed to initialize debugfs for tracing\n");
+               goto err_fnic_trace_debugfs_init;
+       }
+       pr_info("fnic: Successfully Initialized Trace Buffer\n");
+       return err;
+err_fnic_trace_debugfs_init:
+       fnic_trace_free();
+err_fnic_trace_buf_init:
+       return err;
+}
+
+/*
+ * fnic_trace_free - Free memory of fnic trace data structures.
+ */
+void fnic_trace_free(void)
+{
+       fnic_tracing_enabled = 0;
+       fnic_trace_debugfs_terminate();
+       if (fnic_trace_entries.page_offset) {
+               vfree((void *)fnic_trace_entries.page_offset);
+               fnic_trace_entries.page_offset = NULL;
+       }
+       if (fnic_trace_buf_p) {
+               vfree((void *)fnic_trace_buf_p);
+               fnic_trace_buf_p = 0;
+       }
+       printk(KERN_INFO PFX "Successfully Freed Trace Buffer\n");
+}
+
+/*
+ * fnic_fc_ctlr_trace_buf_init -
+ * Initialize trace buffer to log fnic control frames
+ * Description:
+ * Initialize trace buffer data structure by allocating
+ * required memory for trace data as well as for Indexes.
+ * Frame size is 256 bytes and
+ * memory is allocated for 1024 entries of 256 bytes.
+ * Page_offset(Index) is set to the address of trace entry
+ * and page_offset is initialized by adding frame size
+ * to the previous page_offset entry.
+ */
+
+int fnic_fc_trace_init(void)
+{
+       unsigned long fc_trace_buf_head;
+       int err = 0;
+       int i;
+
+       fc_trace_max_entries = (fnic_fc_trace_max_pages * PAGE_SIZE)/
+                               FC_TRC_SIZE_BYTES;
+       fnic_fc_ctlr_trace_buf_p = (unsigned long)vmalloc(
+                                       fnic_fc_trace_max_pages * PAGE_SIZE);
+       if (!fnic_fc_ctlr_trace_buf_p) {
+               pr_err("fnic: Failed to allocate memory for "
+                      "FC Control Trace Buf\n");
+               err = -ENOMEM;
+               goto err_fnic_fc_ctlr_trace_buf_init;
+       }
+
+       memset((void *)fnic_fc_ctlr_trace_buf_p, 0,
+                       fnic_fc_trace_max_pages * PAGE_SIZE);
+
+       /* Allocate memory for page offset */
+       fc_trace_entries.page_offset = vmalloc(fc_trace_max_entries *
+                                               sizeof(unsigned long));
+       if (!fc_trace_entries.page_offset) {
+               pr_err("fnic:Failed to allocate memory for page_offset\n");
+               if (fnic_fc_ctlr_trace_buf_p) {
+                       pr_err("fnic: Freeing FC Control Trace Buf\n");
+                       vfree((void *)fnic_fc_ctlr_trace_buf_p);
+                       fnic_fc_ctlr_trace_buf_p = 0;
+               }
+               err = -ENOMEM;
+               goto err_fnic_fc_ctlr_trace_buf_init;
+       }
+       memset((void *)fc_trace_entries.page_offset, 0,
+              (fc_trace_max_entries * sizeof(unsigned long)));
+
+       fc_trace_entries.rd_idx = fc_trace_entries.wr_idx = 0;
+       fc_trace_buf_head = fnic_fc_ctlr_trace_buf_p;
+
+       /*
+       * Set up fc_trace_entries.page_offset field with memory location
+       * for every trace entry
+       */
+       for (i = 0; i < fc_trace_max_entries; i++) {
+               fc_trace_entries.page_offset[i] = fc_trace_buf_head;
+               fc_trace_buf_head += FC_TRC_SIZE_BYTES;
+       }
+       err = fnic_fc_trace_debugfs_init();
+       if (err < 0) {
+               pr_err("fnic: Failed to initialize FC_CTLR tracing.\n");
+               goto err_fnic_fc_ctlr_trace_debugfs_init;
+       }
+       pr_info("fnic: Successfully Initialized FC_CTLR Trace Buffer\n");
+       return err;
+
+err_fnic_fc_ctlr_trace_debugfs_init:
+       fnic_fc_trace_free();
+err_fnic_fc_ctlr_trace_buf_init:
+       return err;
+}
+
+/*
+ * Fnic_fc_ctlr_trace_free - Free memory of fnic_fc_ctlr trace data structures.
+ */
+void fnic_fc_trace_free(void)
+{
+       fnic_fc_tracing_enabled = 0;
+       fnic_fc_trace_debugfs_terminate();
+       if (fc_trace_entries.page_offset) {
+               vfree((void *)fc_trace_entries.page_offset);
+               fc_trace_entries.page_offset = NULL;
+       }
+       if (fnic_fc_ctlr_trace_buf_p) {
+               vfree((void *)fnic_fc_ctlr_trace_buf_p);
+               fnic_fc_ctlr_trace_buf_p = 0;
+       }
+       pr_info("fnic:Successfully FC_CTLR Freed Trace Buffer\n");
+}
+
+/*
+ * fnic_fc_ctlr_set_trace_data:
+ *       Maintain rd & wr idx accordingly and set data
+ * Passed parameters:
+ *       host_no: host number accociated with fnic
+ *       frame_type: send_frame, rece_frame or link event
+ *       fc_frame: pointer to fc_frame
+ *       frame_len: Length of the fc_frame
+ * Description:
+ *   This routine will get next available wr_idx and
+ *   copy all passed trace data to the buffer pointed by wr_idx
+ *   and increment wr_idx. It will also make sure that we dont
+ *   overwrite the entry which we are reading and also
+ *   wrap around if we reach the maximum entries.
+ * Returned Value:
+ *   It will return 0 for success or -1 for failure
+ */
+int fnic_fc_trace_set_data(u32 host_no, u8 frame_type,
+                               char *frame, u32 fc_trc_frame_len)
+{
+       unsigned long flags;
+       struct fc_trace_hdr *fc_buf;
+       unsigned long eth_fcoe_hdr_len;
+       char *fc_trace;
+
+       if (fnic_fc_tracing_enabled == 0)
+               return 0;
+
+       spin_lock_irqsave(&fnic_fc_trace_lock, flags);
+
+       if (fnic_fc_trace_cleared == 1) {
+               fc_trace_entries.rd_idx = fc_trace_entries.wr_idx = 0;
+               pr_info("fnic: Resetting the read idx\n");
+               memset((void *)fnic_fc_ctlr_trace_buf_p, 0,
+                               fnic_fc_trace_max_pages * PAGE_SIZE);
+               fnic_fc_trace_cleared = 0;
+       }
+
+       fc_buf = (struct fc_trace_hdr *)
+               fc_trace_entries.page_offset[fc_trace_entries.wr_idx];
+
+       fc_trace_entries.wr_idx++;
+
+       if (fc_trace_entries.wr_idx >= fc_trace_max_entries)
+               fc_trace_entries.wr_idx = 0;
+
+       if (fc_trace_entries.wr_idx == fc_trace_entries.rd_idx) {
+               fc_trace_entries.rd_idx++;
+               if (fc_trace_entries.rd_idx >= fc_trace_max_entries)
+                       fc_trace_entries.rd_idx = 0;
+       }
+
+       fc_buf->time_stamp = CURRENT_TIME;
+       fc_buf->host_no = host_no;
+       fc_buf->frame_type = frame_type;
+
+       fc_trace = (char *)FC_TRACE_ADDRESS(fc_buf);
+
+       /* During the receive path, we do not have eth hdr as well as fcoe hdr
+        * at trace entry point so we will stuff 0xff just to make it generic.
+        */
+       if (frame_type == FNIC_FC_RECV) {
+               eth_fcoe_hdr_len = sizeof(struct ethhdr) +
+                                       sizeof(struct fcoe_hdr);
+               memset((char *)fc_trace, 0xff, eth_fcoe_hdr_len);
+               /* Copy the rest of data frame */
+               memcpy((char *)(fc_trace + eth_fcoe_hdr_len), (void *)frame,
+               min_t(u8, fc_trc_frame_len,
+                       (u8)(FC_TRC_SIZE_BYTES - FC_TRC_HEADER_SIZE
+                                               - eth_fcoe_hdr_len)));
+       } else {
+               memcpy((char *)fc_trace, (void *)frame,
+               min_t(u8, fc_trc_frame_len,
+                       (u8)(FC_TRC_SIZE_BYTES - FC_TRC_HEADER_SIZE)));
+       }
+
+       /* Store the actual received length */
+       fc_buf->frame_len = fc_trc_frame_len;
+
+       spin_unlock_irqrestore(&fnic_fc_trace_lock, flags);
+       return 0;
+}
+
+/*
+ * fnic_fc_ctlr_get_trace_data: Copy trace buffer to a memory file
+ * Passed parameter:
+ *       @fnic_dbgfs_t: pointer to debugfs trace buffer
+ *       rdata_flag: 1 => Unformated file
+ *                   0 => formated file
+ * Description:
+ *       This routine will copy the trace data to memory file with
+ *       proper formatting and also copy to another memory
+ *       file without formatting for further procesing.
+ * Retrun Value:
+ *       Number of bytes that were dumped into fnic_dbgfs_t
+ */
+
+int fnic_fc_trace_get_data(fnic_dbgfs_t *fnic_dbgfs_prt, u8 rdata_flag)
+{
+       int rd_idx, wr_idx;
+       unsigned long flags;
+       int len = 0, j;
+       struct fc_trace_hdr *tdata;
+       char *fc_trace;
+
+       spin_lock_irqsave(&fnic_fc_trace_lock, flags);
+       if (fc_trace_entries.wr_idx == fc_trace_entries.rd_idx) {
+               spin_unlock_irqrestore(&fnic_fc_trace_lock, flags);
+               pr_info("fnic: Buffer is empty\n");
+               return 0;
+       }
+       rd_idx = fc_trace_entries.rd_idx;
+       wr_idx = fc_trace_entries.wr_idx;
+       if (rdata_flag == 0) {
+               len += snprintf(fnic_dbgfs_prt->buffer + len,
+                       (fnic_fc_trace_max_pages * PAGE_SIZE * 3) - len,
+                       "Time Stamp (UTC)\t\t"
+                       "Host No:   F Type:  len:     FCoE_FRAME:\n");
+       }
+
+       while (rd_idx != wr_idx) {
+               tdata = (struct fc_trace_hdr *)
+                       fc_trace_entries.page_offset[rd_idx];
+               if (!tdata) {
+                       pr_info("fnic: Rd data is NULL\n");
+                       spin_unlock_irqrestore(&fnic_fc_trace_lock, flags);
+                       return 0;
+               }
+               if (rdata_flag == 0) {
+                       copy_and_format_trace_data(tdata,
+                               fnic_dbgfs_prt, &len, rdata_flag);
+               } else {
+                       fc_trace = (char *)tdata;
+                       for (j = 0; j < FC_TRC_SIZE_BYTES; j++) {
+                               len += snprintf(fnic_dbgfs_prt->buffer + len,
+                               (fnic_fc_trace_max_pages * PAGE_SIZE * 3)
+                               - len, "%02x", fc_trace[j] & 0xff);
+                       } /* for loop */
+                       len += snprintf(fnic_dbgfs_prt->buffer + len,
+                               (fnic_fc_trace_max_pages * PAGE_SIZE * 3) - len,
+                               "\n");
+               }
+               rd_idx++;
+               if (rd_idx > (fc_trace_max_entries - 1))
+                       rd_idx = 0;
+       }
+
+       spin_unlock_irqrestore(&fnic_fc_trace_lock, flags);
+       return len;
+}
+
+/*
+ * copy_and_format_trace_data: Copy formatted data to char * buffer
+ * Passed Parameter:
+ *      @fc_trace_hdr_t: pointer to trace data
+ *      @fnic_dbgfs_t: pointer to debugfs trace buffer
+ *      @orig_len: pointer to len
+ *      rdata_flag: 0 => Formated file, 1 => Unformated file
+ * Description:
+ *      This routine will format and copy the passed trace data
+ *      for formated file or unformated file accordingly.
+ */
+
+void copy_and_format_trace_data(struct fc_trace_hdr *tdata,
+                               fnic_dbgfs_t *fnic_dbgfs_prt, int *orig_len,
+                               u8 rdata_flag)
+{
+       struct tm tm;
+       int j, i = 1, len;
+       char *fc_trace, *fmt;
+       int ethhdr_len = sizeof(struct ethhdr) - 1;
+       int fcoehdr_len = sizeof(struct fcoe_hdr);
+       int fchdr_len = sizeof(struct fc_frame_header);
+       int max_size = fnic_fc_trace_max_pages * PAGE_SIZE * 3;
+
+       tdata->frame_type = tdata->frame_type & 0x7F;
+
+       len = *orig_len;
+
+       time_to_tm(tdata->time_stamp.tv_sec, 0, &tm);
+
+       fmt = "%02d:%02d:%04ld %02d:%02d:%02d.%09lu ns%8x       %c%8x\t";
+       len += snprintf(fnic_dbgfs_prt->buffer + len,
+               max_size - len,
+               fmt,
+               tm.tm_mon + 1, tm.tm_mday, tm.tm_year + 1900,
+               tm.tm_hour, tm.tm_min, tm.tm_sec,
+               tdata->time_stamp.tv_nsec, tdata->host_no,
+               tdata->frame_type, tdata->frame_len);
+
+       fc_trace = (char *)FC_TRACE_ADDRESS(tdata);
+
+       for (j = 0; j < min_t(u8, tdata->frame_len,
+               (u8)(FC_TRC_SIZE_BYTES - FC_TRC_HEADER_SIZE)); j++) {
+               if (tdata->frame_type == FNIC_FC_LE) {
+                       len += snprintf(fnic_dbgfs_prt->buffer + len,
+                               max_size - len, "%c", fc_trace[j]);
+               } else {
+                       len += snprintf(fnic_dbgfs_prt->buffer + len,
+                               max_size - len, "%02x", fc_trace[j] & 0xff);
+                       len += snprintf(fnic_dbgfs_prt->buffer + len,
+                               max_size - len, " ");
+                       if (j == ethhdr_len ||
+                               j == ethhdr_len + fcoehdr_len ||
+                               j == ethhdr_len + fcoehdr_len + fchdr_len ||
+                               (i > 3 && j%fchdr_len == 0)) {
+                               len += snprintf(fnic_dbgfs_prt->buffer
+                                       + len, max_size - len,
+                                       "\n\t\t\t\t\t\t\t\t");
+                               i++;
+                       }
+               } /* end of else*/
+       } /* End of for loop*/
+       len += snprintf(fnic_dbgfs_prt->buffer + len,
+               max_size - len, "\n");
+       *orig_len = len;
+}