--- /dev/null
+/*
+ * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
+ * Based on.......: linux/drivers/s390/block/mdisk.c
+ * ...............: by Hartmunt Penner <hpenner@de.ibm.com>
+ * Bugreports.to..: <Linux390@de.ibm.com>
+ * Copyright IBM Corp. 1999, 2000
+ *
+ */
+
+#define KMSG_COMPONENT "dasd"
+
+#include <linux/kernel_stat.h>
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/hdreg.h>
+#include <linux/bio.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+
+#include <asm/dasd.h>
+#include <asm/debug.h>
+#include <asm/ebcdic.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/vtoc.h>
+#include <asm/diag.h>
+
+#include "dasd_int.h"
+#include "dasd_diag.h"
+
+#define PRINTK_HEADER "dasd(diag):"
+
+MODULE_LICENSE("GPL");
+
+/* The maximum number of blocks per request (max_blocks) is dependent on the
+ * amount of storage that is available in the static I/O buffer for each
+ * device. Currently each device gets 2 pages. We want to fit two requests
+ * into the available memory so that we can immediately start the next if one
+ * finishes. */
+#define DIAG_MAX_BLOCKS (((2 * PAGE_SIZE - sizeof(struct dasd_ccw_req) - \
+ sizeof(struct dasd_diag_req)) / \
+ sizeof(struct dasd_diag_bio)) / 2)
+#define DIAG_MAX_RETRIES 32
+#define DIAG_TIMEOUT 50
+
+static struct dasd_discipline dasd_diag_discipline;
+
+struct dasd_diag_private {
+ struct dasd_diag_characteristics rdc_data;
+ struct dasd_diag_rw_io iob;
+ struct dasd_diag_init_io iib;
+ blocknum_t pt_block;
+ struct ccw_dev_id dev_id;
+};
+
+struct dasd_diag_req {
+ unsigned int block_count;
+ struct dasd_diag_bio bio[0];
+};
+
+static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */
+
+/* Perform DIAG250 call with block I/O parameter list iob (input and output)
+ * and function code cmd.
+ * In case of an exception return 3. Otherwise return result of bitwise OR of
+ * resulting condition code and DIAG return code. */
+static inline int dia250(void *iob, int cmd)
+{
+ register unsigned long reg2 asm ("2") = (unsigned long) iob;
+ typedef union {
+ struct dasd_diag_init_io init_io;
+ struct dasd_diag_rw_io rw_io;
+ } addr_type;
+ int rc;
+
+ rc = 3;
+ asm volatile(
+ " diag 2,%2,0x250\n"
+ "0: ipm %0\n"
+ " srl %0,28\n"
+ " or %0,3\n"
+ "1:\n"
+ EX_TABLE(0b,1b)
+ : "+d" (rc), "=m" (*(addr_type *) iob)
+ : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob)
+ : "3", "cc");
+ return rc;
+}
+
+/* Initialize block I/O to DIAG device using the specified blocksize and
+ * block offset. On success, return zero and set end_block to contain the
+ * number of blocks on the device minus the specified offset. Return non-zero
+ * otherwise. */
+static inline int
+mdsk_init_io(struct dasd_device *device, unsigned int blocksize,
+ blocknum_t offset, blocknum_t *end_block)
+{
+ struct dasd_diag_private *private;
+ struct dasd_diag_init_io *iib;
+ int rc;
+
+ private = (struct dasd_diag_private *) device->private;
+ iib = &private->iib;
+ memset(iib, 0, sizeof (struct dasd_diag_init_io));
+
+ iib->dev_nr = private->dev_id.devno;
+ iib->block_size = blocksize;
+ iib->offset = offset;
+ iib->flaga = DASD_DIAG_FLAGA_DEFAULT;
+
+ rc = dia250(iib, INIT_BIO);
+
+ if ((rc & 3) == 0 && end_block)
+ *end_block = iib->end_block;
+
+ return rc;
+}
+
+/* Remove block I/O environment for device. Return zero on success, non-zero
+ * otherwise. */
+static inline int
+mdsk_term_io(struct dasd_device * device)
+{
+ struct dasd_diag_private *private;
+ struct dasd_diag_init_io *iib;
+ int rc;
+
+ private = (struct dasd_diag_private *) device->private;
+ iib = &private->iib;
+ memset(iib, 0, sizeof (struct dasd_diag_init_io));
+ iib->dev_nr = private->dev_id.devno;
+ rc = dia250(iib, TERM_BIO);
+ return rc;
+}
+
+/* Error recovery for failed DIAG requests - try to reestablish the DIAG
+ * environment. */
+static void
+dasd_diag_erp(struct dasd_device *device)
+{
+ int rc;
+
+ mdsk_term_io(device);
+ rc = mdsk_init_io(device, device->block->bp_block, 0, NULL);
+ if (rc == 4) {
+ if (!(test_and_set_bit(DASD_FLAG_DEVICE_RO, &device->flags)))
+ pr_warning("%s: The access mode of a DIAG device "
+ "changed to read-only\n",
+ dev_name(&device->cdev->dev));
+ rc = 0;
+ }
+ if (rc)
+ pr_warning("%s: DIAG ERP failed with "
+ "rc=%d\n", dev_name(&device->cdev->dev), rc);
+}
+
+/* Start a given request at the device. Return zero on success, non-zero
+ * otherwise. */
+static int
+dasd_start_diag(struct dasd_ccw_req * cqr)
+{
+ struct dasd_device *device;
+ struct dasd_diag_private *private;
+ struct dasd_diag_req *dreq;
+ int rc;
+
+ device = cqr->startdev;
+ if (cqr->retries < 0) {
+ DBF_DEV_EVENT(DBF_ERR, device, "DIAG start_IO: request %p "
+ "- no retry left)", cqr);
+ cqr->status = DASD_CQR_ERROR;
+ return -EIO;
+ }
+ private = (struct dasd_diag_private *) device->private;
+ dreq = (struct dasd_diag_req *) cqr->data;
+
+ private->iob.dev_nr = private->dev_id.devno;
+ private->iob.key = 0;
+ private->iob.flags = DASD_DIAG_RWFLAG_ASYNC;
+ private->iob.block_count = dreq->block_count;
+ private->iob.interrupt_params = (addr_t) cqr;
+ private->iob.bio_list = dreq->bio;
+ private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
+
+ cqr->startclk = get_tod_clock();
+ cqr->starttime = jiffies;
+ cqr->retries--;
+
+ rc = dia250(&private->iob, RW_BIO);
+ switch (rc) {
+ case 0: /* Synchronous I/O finished successfully */
+ cqr->stopclk = get_tod_clock();
+ cqr->status = DASD_CQR_SUCCESS;
+ /* Indicate to calling function that only a dasd_schedule_bh()
+ and no timer is needed */
+ rc = -EACCES;
+ break;
+ case 8: /* Asynchronous I/O was started */
+ cqr->status = DASD_CQR_IN_IO;
+ rc = 0;
+ break;
+ default: /* Error condition */
+ cqr->status = DASD_CQR_QUEUED;
+ DBF_DEV_EVENT(DBF_WARNING, device, "dia250 returned rc=%d", rc);
+ dasd_diag_erp(device);
+ rc = -EIO;
+ break;
+ }
+ cqr->intrc = rc;
+ return rc;
+}
+
+/* Terminate given request at the device. */
+static int
+dasd_diag_term_IO(struct dasd_ccw_req * cqr)
+{
+ struct dasd_device *device;
+
+ device = cqr->startdev;
+ mdsk_term_io(device);
+ mdsk_init_io(device, device->block->bp_block, 0, NULL);
+ cqr->status = DASD_CQR_CLEAR_PENDING;
+ cqr->stopclk = get_tod_clock();
+ dasd_schedule_device_bh(device);
+ return 0;
+}
+
+/* Handle external interruption. */
+static void dasd_ext_handler(struct ext_code ext_code,
+ unsigned int param32, unsigned long param64)
+{
+ struct dasd_ccw_req *cqr, *next;
+ struct dasd_device *device;
+ unsigned long long expires;
+ unsigned long flags;
+ addr_t ip;
+ int rc;
+
+ switch (ext_code.subcode >> 8) {
+ case DASD_DIAG_CODE_31BIT:
+ ip = (addr_t) param32;
+ break;
+ case DASD_DIAG_CODE_64BIT:
+ ip = (addr_t) param64;
+ break;
+ default:
+ return;
+ }
+ inc_irq_stat(IRQEXT_DSD);
+ if (!ip) { /* no intparm: unsolicited interrupt */
+ DBF_EVENT(DBF_NOTICE, "%s", "caught unsolicited "
+ "interrupt");
+ return;
+ }
+ cqr = (struct dasd_ccw_req *) ip;
+ device = (struct dasd_device *) cqr->startdev;
+ if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
+ DBF_DEV_EVENT(DBF_WARNING, device,
+ " magic number of dasd_ccw_req 0x%08X doesn't"
+ " match discipline 0x%08X",
+ cqr->magic, *(int *) (&device->discipline->name));
+ return;
+ }
+
+ /* get irq lock to modify request queue */
+ spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
+
+ /* Check for a pending clear operation */
+ if (cqr->status == DASD_CQR_CLEAR_PENDING) {
+ cqr->status = DASD_CQR_CLEARED;
+ dasd_device_clear_timer(device);
+ dasd_schedule_device_bh(device);
+ spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
+ return;
+ }
+
+ cqr->stopclk = get_tod_clock();
+
+ expires = 0;
+ if ((ext_code.subcode & 0xff) == 0) {
+ cqr->status = DASD_CQR_SUCCESS;
+ /* Start first request on queue if possible -> fast_io. */
+ if (!list_empty(&device->ccw_queue)) {
+ next = list_entry(device->ccw_queue.next,
+ struct dasd_ccw_req, devlist);
+ if (next->status == DASD_CQR_QUEUED) {
+ rc = dasd_start_diag(next);
+ if (rc == 0)
+ expires = next->expires;
+ }
+ }
+ } else {
+ cqr->status = DASD_CQR_QUEUED;
+ DBF_DEV_EVENT(DBF_DEBUG, device, "interrupt status for "
+ "request %p was %d (%d retries left)", cqr,
+ ext_code.subcode & 0xff, cqr->retries);
+ dasd_diag_erp(device);
+ }
+
+ if (expires != 0)
+ dasd_device_set_timer(device, expires);
+ else
+ dasd_device_clear_timer(device);
+ dasd_schedule_device_bh(device);
+
+ spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
+}
+
+/* Check whether device can be controlled by DIAG discipline. Return zero on
+ * success, non-zero otherwise. */
+static int
+dasd_diag_check_device(struct dasd_device *device)
+{
+ struct dasd_block *block;
+ struct dasd_diag_private *private;
+ struct dasd_diag_characteristics *rdc_data;
+ struct dasd_diag_bio bio;
+ struct vtoc_cms_label *label;
+ blocknum_t end_block;
+ unsigned int sb, bsize;
+ int rc;
+
+ private = (struct dasd_diag_private *) device->private;
+ if (private == NULL) {
+ private = kzalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
+ if (private == NULL) {
+ DBF_DEV_EVENT(DBF_WARNING, device, "%s",
+ "Allocating memory for private DASD data "
+ "failed\n");
+ return -ENOMEM;
+ }
+ ccw_device_get_id(device->cdev, &private->dev_id);
+ device->private = (void *) private;
+ }
+ block = dasd_alloc_block();
+ if (IS_ERR(block)) {
+ DBF_DEV_EVENT(DBF_WARNING, device, "%s",
+ "could not allocate dasd block structure");
+ device->private = NULL;
+ kfree(private);
+ return PTR_ERR(block);
+ }
+ device->block = block;
+ block->base = device;
+
+ /* Read Device Characteristics */
+ rdc_data = (void *) &(private->rdc_data);
+ rdc_data->dev_nr = private->dev_id.devno;
+ rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
+
+ rc = diag210((struct diag210 *) rdc_data);
+ if (rc) {
+ DBF_DEV_EVENT(DBF_WARNING, device, "failed to retrieve device "
+ "information (rc=%d)", rc);
+ rc = -EOPNOTSUPP;
+ goto out;
+ }
+
+ device->default_expires = DIAG_TIMEOUT;
+ device->default_retries = DIAG_MAX_RETRIES;
+
+ /* Figure out position of label block */
+ switch (private->rdc_data.vdev_class) {
+ case DEV_CLASS_FBA:
+ private->pt_block = 1;
+ break;
+ case DEV_CLASS_ECKD:
+ private->pt_block = 2;
+ break;
+ default:
+ pr_warning("%s: Device type %d is not supported "
+ "in DIAG mode\n", dev_name(&device->cdev->dev),
+ private->rdc_data.vdev_class);
+ rc = -EOPNOTSUPP;
+ goto out;
+ }
+
+ DBF_DEV_EVENT(DBF_INFO, device,
+ "%04X: %04X on real %04X/%02X",
+ rdc_data->dev_nr,
+ rdc_data->vdev_type,
+ rdc_data->rdev_type, rdc_data->rdev_model);
+
+ /* terminate all outstanding operations */
+ mdsk_term_io(device);
+
+ /* figure out blocksize of device */
+ label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL);
+ if (label == NULL) {
+ DBF_DEV_EVENT(DBF_WARNING, device, "%s",
+ "No memory to allocate initialization request");
+ rc = -ENOMEM;
+ goto out;
+ }
+ rc = 0;
+ end_block = 0;
+ /* try all sizes - needed for ECKD devices */
+ for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
+ mdsk_init_io(device, bsize, 0, &end_block);
+ memset(&bio, 0, sizeof (struct dasd_diag_bio));
+ bio.type = MDSK_READ_REQ;
+ bio.block_number = private->pt_block + 1;
+ bio.buffer = label;
+ memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
+ private->iob.dev_nr = rdc_data->dev_nr;
+ private->iob.key = 0;
+ private->iob.flags = 0; /* do synchronous io */
+ private->iob.block_count = 1;
+ private->iob.interrupt_params = 0;
+ private->iob.bio_list = &bio;
+ private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
+ rc = dia250(&private->iob, RW_BIO);
+ if (rc == 3) {
+ pr_warning("%s: A 64-bit DIAG call failed\n",
+ dev_name(&device->cdev->dev));
+ rc = -EOPNOTSUPP;
+ goto out_label;
+ }
+ mdsk_term_io(device);
+ if (rc == 0)
+ break;
+ }
+ if (bsize > PAGE_SIZE) {
+ pr_warning("%s: Accessing the DASD failed because of an "
+ "incorrect format (rc=%d)\n",
+ dev_name(&device->cdev->dev), rc);
+ rc = -EIO;
+ goto out_label;
+ }
+ /* check for label block */
+ if (memcmp(label->label_id, DASD_DIAG_CMS1,
+ sizeof(DASD_DIAG_CMS1)) == 0) {
+ /* get formatted blocksize from label block */
+ bsize = (unsigned int) label->block_size;
+ block->blocks = (unsigned long) label->block_count;
+ } else
+ block->blocks = end_block;
+ block->bp_block = bsize;
+ block->s2b_shift = 0; /* bits to shift 512 to get a block */
+ for (sb = 512; sb < bsize; sb = sb << 1)
+ block->s2b_shift++;
+ rc = mdsk_init_io(device, block->bp_block, 0, NULL);
+ if (rc && (rc != 4)) {
+ pr_warning("%s: DIAG initialization failed with rc=%d\n",
+ dev_name(&device->cdev->dev), rc);
+ rc = -EIO;
+ } else {
+ if (rc == 4)
+ set_bit(DASD_FLAG_DEVICE_RO, &device->flags);
+ pr_info("%s: New DASD with %ld byte/block, total size %ld "
+ "KB%s\n", dev_name(&device->cdev->dev),
+ (unsigned long) block->bp_block,
+ (unsigned long) (block->blocks <<
+ block->s2b_shift) >> 1,
+ (rc == 4) ? ", read-only device" : "");
+ rc = 0;
+ }
+out_label:
+ free_page((long) label);
+out:
+ if (rc) {
+ device->block = NULL;
+ dasd_free_block(block);
+ device->private = NULL;
+ kfree(private);
+ }
+ return rc;
+}
+
+/* Fill in virtual disk geometry for device. Return zero on success, non-zero
+ * otherwise. */
+static int
+dasd_diag_fill_geometry(struct dasd_block *block, struct hd_geometry *geo)
+{
+ if (dasd_check_blocksize(block->bp_block) != 0)
+ return -EINVAL;
+ geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
+ geo->heads = 16;
+ geo->sectors = 128 >> block->s2b_shift;
+ return 0;
+}
+
+static dasd_erp_fn_t
+dasd_diag_erp_action(struct dasd_ccw_req * cqr)
+{
+ return dasd_default_erp_action;
+}
+
+static dasd_erp_fn_t
+dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
+{
+ return dasd_default_erp_postaction;
+}
+
+/* Create DASD request from block device request. Return pointer to new
+ * request on success, ERR_PTR otherwise. */
+static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev,
+ struct dasd_block *block,
+ struct request *req)
+{
+ struct dasd_ccw_req *cqr;
+ struct dasd_diag_req *dreq;
+ struct dasd_diag_bio *dbio;
+ struct req_iterator iter;
+ struct bio_vec bv;
+ char *dst;
+ unsigned int count, datasize;
+ sector_t recid, first_rec, last_rec;
+ unsigned int blksize, off;
+ unsigned char rw_cmd;
+
+ if (rq_data_dir(req) == READ)
+ rw_cmd = MDSK_READ_REQ;
+ else if (rq_data_dir(req) == WRITE)
+ rw_cmd = MDSK_WRITE_REQ;
+ else
+ return ERR_PTR(-EINVAL);
+ blksize = block->bp_block;
+ /* Calculate record id of first and last block. */
+ first_rec = blk_rq_pos(req) >> block->s2b_shift;
+ last_rec =
+ (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
+ /* Check struct bio and count the number of blocks for the request. */
+ count = 0;
+ rq_for_each_segment(bv, req, iter) {
+ if (bv.bv_len & (blksize - 1))
+ /* Fba can only do full blocks. */
+ return ERR_PTR(-EINVAL);
+ count += bv.bv_len >> (block->s2b_shift + 9);
+ }
+ /* Paranoia. */
+ if (count != last_rec - first_rec + 1)
+ return ERR_PTR(-EINVAL);
+ /* Build the request */
+ datasize = sizeof(struct dasd_diag_req) +
+ count*sizeof(struct dasd_diag_bio);
+ cqr = dasd_smalloc_request(DASD_DIAG_MAGIC, 0, datasize, memdev);
+ if (IS_ERR(cqr))
+ return cqr;
+
+ dreq = (struct dasd_diag_req *) cqr->data;
+ dreq->block_count = count;
+ dbio = dreq->bio;
+ recid = first_rec;
+ rq_for_each_segment(bv, req, iter) {
+ dst = page_address(bv.bv_page) + bv.bv_offset;
+ for (off = 0; off < bv.bv_len; off += blksize) {
+ memset(dbio, 0, sizeof (struct dasd_diag_bio));
+ dbio->type = rw_cmd;
+ dbio->block_number = recid + 1;
+ dbio->buffer = dst;
+ dbio++;
+ dst += blksize;
+ recid++;
+ }
+ }
+ cqr->retries = memdev->default_retries;
+ cqr->buildclk = get_tod_clock();
+ if (blk_noretry_request(req) ||
+ block->base->features & DASD_FEATURE_FAILFAST)
+ set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
+ cqr->startdev = memdev;
+ cqr->memdev = memdev;
+ cqr->block = block;
+ cqr->expires = memdev->default_expires * HZ;
+ cqr->status = DASD_CQR_FILLED;
+ return cqr;
+}
+
+/* Release DASD request. Return non-zero if request was successful, zero
+ * otherwise. */
+static int
+dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req)
+{
+ int status;
+
+ status = cqr->status == DASD_CQR_DONE;
+ dasd_sfree_request(cqr, cqr->memdev);
+ return status;
+}
+
+static void dasd_diag_handle_terminated_request(struct dasd_ccw_req *cqr)
+{
+ if (cqr->retries < 0)
+ cqr->status = DASD_CQR_FAILED;
+ else
+ cqr->status = DASD_CQR_FILLED;
+};
+
+/* Fill in IOCTL data for device. */
+static int
+dasd_diag_fill_info(struct dasd_device * device,
+ struct dasd_information2_t * info)
+{
+ struct dasd_diag_private *private;
+
+ private = (struct dasd_diag_private *) device->private;
+ info->label_block = (unsigned int) private->pt_block;
+ info->FBA_layout = 1;
+ info->format = DASD_FORMAT_LDL;
+ info->characteristics_size = sizeof (struct dasd_diag_characteristics);
+ memcpy(info->characteristics,
+ &((struct dasd_diag_private *) device->private)->rdc_data,
+ sizeof (struct dasd_diag_characteristics));
+ info->confdata_size = 0;
+ return 0;
+}
+
+static void
+dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
+ struct irb *stat)
+{
+ DBF_DEV_EVENT(DBF_WARNING, device, "%s",
+ "dump sense not available for DIAG data");
+}
+
+static struct dasd_discipline dasd_diag_discipline = {
+ .owner = THIS_MODULE,
+ .name = "DIAG",
+ .ebcname = "DIAG",
+ .max_blocks = DIAG_MAX_BLOCKS,
+ .check_device = dasd_diag_check_device,
+ .verify_path = dasd_generic_verify_path,
+ .fill_geometry = dasd_diag_fill_geometry,
+ .start_IO = dasd_start_diag,
+ .term_IO = dasd_diag_term_IO,
+ .handle_terminated_request = dasd_diag_handle_terminated_request,
+ .erp_action = dasd_diag_erp_action,
+ .erp_postaction = dasd_diag_erp_postaction,
+ .build_cp = dasd_diag_build_cp,
+ .free_cp = dasd_diag_free_cp,
+ .dump_sense = dasd_diag_dump_sense,
+ .fill_info = dasd_diag_fill_info,
+};
+
+static int __init
+dasd_diag_init(void)
+{
+ if (!MACHINE_IS_VM) {
+ pr_info("Discipline %s cannot be used without z/VM\n",
+ dasd_diag_discipline.name);
+ return -ENODEV;
+ }
+ ASCEBC(dasd_diag_discipline.ebcname, 4);
+
+ irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL);
+ register_external_irq(EXT_IRQ_CP_SERVICE, dasd_ext_handler);
+ dasd_diag_discipline_pointer = &dasd_diag_discipline;
+ return 0;
+}
+
+static void __exit
+dasd_diag_cleanup(void)
+{
+ unregister_external_irq(EXT_IRQ_CP_SERVICE, dasd_ext_handler);
+ irq_subclass_unregister(IRQ_SUBCLASS_SERVICE_SIGNAL);
+ dasd_diag_discipline_pointer = NULL;
+}
+
+module_init(dasd_diag_init);
+module_exit(dasd_diag_cleanup);
Code Review / kvmfornfv.git / blobdiff