#include <linux/device-mapper.h>
#include "dm-path-selector.h"
-#include "dm-bio-record.h"
#include "dm-uevent.h"
#include <linux/ctype.h>
spinlock_t lock;
const char *hw_handler_name;
+ char *hw_handler_params;
unsigned nr_priority_groups;
struct list_head priority_groups;
unsigned pg_init_required; /* pg_init needs calling? */
unsigned pg_init_in_progress; /* Only one pg_init allowed at once */
+ wait_queue_head_t pg_init_wait; /* Wait for pg_init completion */
unsigned nr_valid_paths; /* Total number of usable paths */
struct pgpath *current_pgpath;
unsigned pg_init_count; /* Number of times pg_init called */
struct work_struct process_queued_ios;
- struct bio_list queued_ios;
+ struct list_head queued_ios;
unsigned queue_size;
struct work_struct trigger_event;
* can resubmit bios on error.
*/
mempool_t *mpio_pool;
+
+ struct mutex work_mutex;
};
/*
*/
struct dm_mpath_io {
struct pgpath *pgpath;
- struct dm_bio_details details;
+ size_t nr_bytes;
};
typedef int (*action_fn) (struct pgpath *pgpath);
m = kzalloc(sizeof(*m), GFP_KERNEL);
if (m) {
INIT_LIST_HEAD(&m->priority_groups);
+ INIT_LIST_HEAD(&m->queued_ios);
spin_lock_init(&m->lock);
m->queue_io = 1;
INIT_WORK(&m->process_queued_ios, process_queued_ios);
INIT_WORK(&m->trigger_event, trigger_event);
+ init_waitqueue_head(&m->pg_init_wait);
+ mutex_init(&m->work_mutex);
m->mpio_pool = mempool_create_slab_pool(MIN_IOS, _mpio_cache);
if (!m->mpio_pool) {
kfree(m);
}
kfree(m->hw_handler_name);
+ kfree(m->hw_handler_params);
mempool_destroy(m->mpio_pool);
kfree(m);
}
* Path selection
*-----------------------------------------------*/
+static void __pg_init_all_paths(struct multipath *m)
+{
+ struct pgpath *pgpath;
+
+ m->pg_init_count++;
+ m->pg_init_required = 0;
+ list_for_each_entry(pgpath, &m->current_pg->pgpaths, list) {
+ /* Skip failed paths */
+ if (!pgpath->is_active)
+ continue;
+ if (queue_work(kmpath_handlerd, &pgpath->activate_path))
+ m->pg_init_in_progress++;
+ }
+}
+
static void __switch_pg(struct multipath *m, struct pgpath *pgpath)
{
m->current_pg = pgpath->pg;
m->pg_init_count = 0;
}
-static int __choose_path_in_pg(struct multipath *m, struct priority_group *pg)
+static int __choose_path_in_pg(struct multipath *m, struct priority_group *pg,
+ size_t nr_bytes)
{
struct dm_path *path;
- path = pg->ps.type->select_path(&pg->ps, &m->repeat_count);
+ path = pg->ps.type->select_path(&pg->ps, &m->repeat_count, nr_bytes);
if (!path)
return -ENXIO;
return 0;
}
-static void __choose_pgpath(struct multipath *m)
+static void __choose_pgpath(struct multipath *m, size_t nr_bytes)
{
struct priority_group *pg;
unsigned bypassed = 1;
if (m->next_pg) {
pg = m->next_pg;
m->next_pg = NULL;
- if (!__choose_path_in_pg(m, pg))
+ if (!__choose_path_in_pg(m, pg, nr_bytes))
return;
}
/* Don't change PG until it has no remaining paths */
- if (m->current_pg && !__choose_path_in_pg(m, m->current_pg))
+ if (m->current_pg && !__choose_path_in_pg(m, m->current_pg, nr_bytes))
return;
/*
list_for_each_entry(pg, &m->priority_groups, list) {
if (pg->bypassed == bypassed)
continue;
- if (!__choose_path_in_pg(m, pg))
+ if (!__choose_path_in_pg(m, pg, nr_bytes))
return;
}
} while (bypassed--);
dm_noflush_suspending(m->ti));
}
-static int map_io(struct multipath *m, struct bio *bio,
+static int map_io(struct multipath *m, struct request *clone,
struct dm_mpath_io *mpio, unsigned was_queued)
{
int r = DM_MAPIO_REMAPPED;
+ size_t nr_bytes = blk_rq_bytes(clone);
unsigned long flags;
struct pgpath *pgpath;
+ struct block_device *bdev;
spin_lock_irqsave(&m->lock, flags);
/* Do we need to select a new pgpath? */
if (!m->current_pgpath ||
(!m->queue_io && (m->repeat_count && --m->repeat_count == 0)))
- __choose_pgpath(m);
+ __choose_pgpath(m, nr_bytes);
pgpath = m->current_pgpath;
if ((pgpath && m->queue_io) ||
(!pgpath && m->queue_if_no_path)) {
/* Queue for the daemon to resubmit */
- bio_list_add(&m->queued_ios, bio);
+ list_add_tail(&clone->queuelist, &m->queued_ios);
m->queue_size++;
if ((m->pg_init_required && !m->pg_init_in_progress) ||
!m->queue_io)
queue_work(kmultipathd, &m->process_queued_ios);
pgpath = NULL;
r = DM_MAPIO_SUBMITTED;
- } else if (pgpath)
- bio->bi_bdev = pgpath->path.dev->bdev;
- else if (__must_push_back(m))
+ } else if (pgpath) {
+ bdev = pgpath->path.dev->bdev;
+ clone->q = bdev_get_queue(bdev);
+ clone->rq_disk = bdev->bd_disk;
+ } else if (__must_push_back(m))
r = DM_MAPIO_REQUEUE;
else
r = -EIO; /* Failed */
mpio->pgpath = pgpath;
+ mpio->nr_bytes = nr_bytes;
+
+ if (r == DM_MAPIO_REMAPPED && pgpath->pg->ps.type->start_io)
+ pgpath->pg->ps.type->start_io(&pgpath->pg->ps, &pgpath->path,
+ nr_bytes);
spin_unlock_irqrestore(&m->lock, flags);
{
int r;
unsigned long flags;
- struct bio *bio = NULL, *next;
struct dm_mpath_io *mpio;
union map_info *info;
+ struct request *clone, *n;
+ LIST_HEAD(cl);
spin_lock_irqsave(&m->lock, flags);
- bio = bio_list_get(&m->queued_ios);
+ list_splice_init(&m->queued_ios, &cl);
spin_unlock_irqrestore(&m->lock, flags);
- while (bio) {
- next = bio->bi_next;
- bio->bi_next = NULL;
+ list_for_each_entry_safe(clone, n, &cl, queuelist) {
+ list_del_init(&clone->queuelist);
- info = dm_get_mapinfo(bio);
+ info = dm_get_rq_mapinfo(clone);
mpio = info->ptr;
- r = map_io(m, bio, mpio, 1);
- if (r < 0)
- bio_endio(bio, r);
- else if (r == DM_MAPIO_REMAPPED)
- generic_make_request(bio);
- else if (r == DM_MAPIO_REQUEUE)
- bio_endio(bio, -EIO);
-
- bio = next;
+ r = map_io(m, clone, mpio, 1);
+ if (r < 0) {
+ mempool_free(mpio, m->mpio_pool);
+ dm_kill_unmapped_request(clone, r);
+ } else if (r == DM_MAPIO_REMAPPED)
+ dm_dispatch_request(clone);
+ else if (r == DM_MAPIO_REQUEUE) {
+ mempool_free(mpio, m->mpio_pool);
+ dm_requeue_unmapped_request(clone);
+ }
}
}
{
struct multipath *m =
container_of(work, struct multipath, process_queued_ios);
- struct pgpath *pgpath = NULL, *tmp;
+ struct pgpath *pgpath = NULL;
unsigned must_queue = 1;
unsigned long flags;
goto out;
if (!m->current_pgpath)
- __choose_pgpath(m);
+ __choose_pgpath(m, 0);
pgpath = m->current_pgpath;
(!pgpath && !m->queue_if_no_path))
must_queue = 0;
- if (m->pg_init_required && !m->pg_init_in_progress && pgpath) {
- m->pg_init_count++;
- m->pg_init_required = 0;
- list_for_each_entry(tmp, &pgpath->pg->pgpaths, list) {
- if (queue_work(kmpath_handlerd, &tmp->activate_path))
- m->pg_init_in_progress++;
- }
- }
+ if (m->pg_init_required && !m->pg_init_in_progress && pgpath)
+ __pg_init_all_paths(m);
+
out:
spin_unlock_irqrestore(&m->lock, flags);
if (!must_queue)
if (!p)
return ERR_PTR(-ENOMEM);
- r = dm_get_device(ti, shift(as), ti->begin, ti->len,
- dm_table_get_mode(ti->table), &p->path.dev);
+ r = dm_get_device(ti, shift(as), dm_table_get_mode(ti->table),
+ &p->path.dev);
if (r) {
ti->error = "error getting device";
goto bad;
dm_put_device(ti, p->path.dev);
goto bad;
}
+
+ if (m->hw_handler_params) {
+ r = scsi_dh_set_params(q, m->hw_handler_params);
+ if (r < 0) {
+ ti->error = "unable to set hardware "
+ "handler parameters";
+ scsi_dh_detach(q);
+ dm_put_device(ti, p->path.dev);
+ goto bad;
+ }
+ }
}
r = ps->type->add_path(ps, &p->path, as->argc, as->argv, &ti->error);
static int parse_hw_handler(struct arg_set *as, struct multipath *m)
{
unsigned hw_argc;
+ int ret;
struct dm_target *ti = m->ti;
static struct param _params[] = {
request_module("scsi_dh_%s", m->hw_handler_name);
if (scsi_dh_handler_exist(m->hw_handler_name) == 0) {
ti->error = "unknown hardware handler type";
- kfree(m->hw_handler_name);
- m->hw_handler_name = NULL;
- return -EINVAL;
+ ret = -EINVAL;
+ goto fail;
}
- if (hw_argc > 1)
- DMWARN("Ignoring user-specified arguments for "
- "hardware handler \"%s\"", m->hw_handler_name);
+ if (hw_argc > 1) {
+ char *p;
+ int i, j, len = 4;
+
+ for (i = 0; i <= hw_argc - 2; i++)
+ len += strlen(as->argv[i]) + 1;
+ p = m->hw_handler_params = kzalloc(len, GFP_KERNEL);
+ if (!p) {
+ ti->error = "memory allocation failed";
+ ret = -ENOMEM;
+ goto fail;
+ }
+ j = sprintf(p, "%d", hw_argc - 1);
+ for (i = 0, p+=j+1; i <= hw_argc - 2; i++, p+=j+1)
+ j = sprintf(p, "%s", as->argv[i]);
+ }
consume(as, hw_argc - 1);
return 0;
+fail:
+ kfree(m->hw_handler_name);
+ m->hw_handler_name = NULL;
+ return ret;
}
static int parse_features(struct arg_set *as, struct multipath *m)
return r;
}
-static void multipath_dtr(struct dm_target *ti)
+static void multipath_wait_for_pg_init_completion(struct multipath *m)
{
- struct multipath *m = (struct multipath *) ti->private;
+ DECLARE_WAITQUEUE(wait, current);
+ unsigned long flags;
+
+ add_wait_queue(&m->pg_init_wait, &wait);
+
+ while (1) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+
+ spin_lock_irqsave(&m->lock, flags);
+ if (!m->pg_init_in_progress) {
+ spin_unlock_irqrestore(&m->lock, flags);
+ break;
+ }
+ spin_unlock_irqrestore(&m->lock, flags);
+
+ io_schedule();
+ }
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&m->pg_init_wait, &wait);
+}
+
+static void flush_multipath_work(struct multipath *m)
+{
flush_workqueue(kmpath_handlerd);
+ multipath_wait_for_pg_init_completion(m);
flush_workqueue(kmultipathd);
flush_scheduled_work();
+}
+
+static void multipath_dtr(struct dm_target *ti)
+{
+ struct multipath *m = ti->private;
+
+ flush_multipath_work(m);
free_multipath(m);
}
/*
- * Map bios, recording original fields for later in case we have to resubmit
+ * Map cloned requests
*/
-static int multipath_map(struct dm_target *ti, struct bio *bio,
+static int multipath_map(struct dm_target *ti, struct request *clone,
union map_info *map_context)
{
int r;
struct dm_mpath_io *mpio;
struct multipath *m = (struct multipath *) ti->private;
- mpio = mempool_alloc(m->mpio_pool, GFP_NOIO);
- dm_bio_record(&mpio->details, bio);
+ mpio = mempool_alloc(m->mpio_pool, GFP_ATOMIC);
+ if (!mpio)
+ /* ENOMEM, requeue */
+ return DM_MAPIO_REQUEUE;
+ memset(mpio, 0, sizeof(*mpio));
map_context->ptr = mpio;
- bio->bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT);
- r = map_io(m, bio, mpio, 0);
+ clone->cmd_flags |= REQ_FAILFAST_TRANSPORT;
+ r = map_io(m, clone, mpio, 0);
if (r < 0 || r == DM_MAPIO_REQUEUE)
mempool_free(mpio, m->mpio_pool);
return limit_reached;
}
-static void pg_init_done(struct dm_path *path, int errors)
+static void pg_init_done(void *data, int errors)
{
- struct pgpath *pgpath = path_to_pgpath(path);
+ struct pgpath *pgpath = data;
struct priority_group *pg = pgpath->pg;
struct multipath *m = pg->m;
unsigned long flags;
errors = 0;
break;
}
- DMERR("Cannot failover device because scsi_dh_%s was not "
- "loaded.", m->hw_handler_name);
+ DMERR("Could not failover the device: Handler scsi_dh_%s "
+ "Error %d.", m->hw_handler_name, errors);
/*
* Fail path for now, so we do not ping pong
*/
m->current_pgpath = NULL;
m->current_pg = NULL;
}
- } else if (!m->pg_init_required) {
- m->queue_io = 0;
+ } else if (!m->pg_init_required)
pg->bypassed = 0;
- }
- m->pg_init_in_progress--;
- if (!m->pg_init_in_progress)
- queue_work(kmultipathd, &m->process_queued_ios);
+ if (--m->pg_init_in_progress)
+ /* Activations of other paths are still on going */
+ goto out;
+
+ if (!m->pg_init_required)
+ m->queue_io = 0;
+
+ queue_work(kmultipathd, &m->process_queued_ios);
+
+ /*
+ * Wake up any thread waiting to suspend.
+ */
+ wake_up(&m->pg_init_wait);
+
+out:
spin_unlock_irqrestore(&m->lock, flags);
}
static void activate_path(struct work_struct *work)
{
- int ret;
struct pgpath *pgpath =
container_of(work, struct pgpath, activate_path);
- ret = scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev));
- pg_init_done(&pgpath->path, ret);
+ scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev),
+ pg_init_done, pgpath);
}
/*
* end_io handling
*/
-static int do_end_io(struct multipath *m, struct bio *bio,
+static int do_end_io(struct multipath *m, struct request *clone,
int error, struct dm_mpath_io *mpio)
{
+ /*
+ * We don't queue any clone request inside the multipath target
+ * during end I/O handling, since those clone requests don't have
+ * bio clones. If we queue them inside the multipath target,
+ * we need to make bio clones, that requires memory allocation.
+ * (See drivers/md/dm.c:end_clone_bio() about why the clone requests
+ * don't have bio clones.)
+ * Instead of queueing the clone request here, we queue the original
+ * request into dm core, which will remake a clone request and
+ * clone bios for it and resubmit it later.
+ */
+ int r = DM_ENDIO_REQUEUE;
unsigned long flags;
- if (!error)
+ if (!error && !clone->errors)
return 0; /* I/O complete */
- if ((error == -EWOULDBLOCK) && bio_rw_ahead(bio))
- return error;
-
if (error == -EOPNOTSUPP)
return error;
- spin_lock_irqsave(&m->lock, flags);
- if (!m->nr_valid_paths) {
- if (__must_push_back(m)) {
- spin_unlock_irqrestore(&m->lock, flags);
- return DM_ENDIO_REQUEUE;
- } else if (!m->queue_if_no_path) {
- spin_unlock_irqrestore(&m->lock, flags);
- return -EIO;
- } else {
- spin_unlock_irqrestore(&m->lock, flags);
- goto requeue;
- }
- }
- spin_unlock_irqrestore(&m->lock, flags);
-
if (mpio->pgpath)
fail_path(mpio->pgpath);
- requeue:
- dm_bio_restore(&mpio->details, bio);
-
- /* queue for the daemon to resubmit or fail */
spin_lock_irqsave(&m->lock, flags);
- bio_list_add(&m->queued_ios, bio);
- m->queue_size++;
- if (!m->queue_io)
- queue_work(kmultipathd, &m->process_queued_ios);
+ if (!m->nr_valid_paths && !m->queue_if_no_path && !__must_push_back(m))
+ r = -EIO;
spin_unlock_irqrestore(&m->lock, flags);
- return DM_ENDIO_INCOMPLETE; /* io not complete */
+ return r;
}
-static int multipath_end_io(struct dm_target *ti, struct bio *bio,
+static int multipath_end_io(struct dm_target *ti, struct request *clone,
int error, union map_info *map_context)
{
struct multipath *m = ti->private;
struct path_selector *ps;
int r;
- r = do_end_io(m, bio, error, mpio);
+ r = do_end_io(m, clone, error, mpio);
if (pgpath) {
ps = &pgpath->pg->ps;
if (ps->type->end_io)
- ps->type->end_io(ps, &pgpath->path);
+ ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes);
}
- if (r != DM_ENDIO_INCOMPLETE)
- mempool_free(mpio, m->mpio_pool);
+ mempool_free(mpio, m->mpio_pool);
return r;
}
queue_if_no_path(m, 0, 1);
}
+static void multipath_postsuspend(struct dm_target *ti)
+{
+ struct multipath *m = ti->private;
+
+ mutex_lock(&m->work_mutex);
+ flush_multipath_work(m);
+ mutex_unlock(&m->work_mutex);
+}
+
/*
* Restore the queue_if_no_path setting.
*/
static int multipath_message(struct dm_target *ti, unsigned argc, char **argv)
{
- int r;
+ int r = -EINVAL;
struct dm_dev *dev;
struct multipath *m = (struct multipath *) ti->private;
action_fn action;
+ mutex_lock(&m->work_mutex);
+
+ if (dm_suspended(ti)) {
+ r = -EBUSY;
+ goto out;
+ }
+
if (argc == 1) {
- if (!strnicmp(argv[0], MESG_STR("queue_if_no_path")))
- return queue_if_no_path(m, 1, 0);
- else if (!strnicmp(argv[0], MESG_STR("fail_if_no_path")))
- return queue_if_no_path(m, 0, 0);
+ if (!strnicmp(argv[0], MESG_STR("queue_if_no_path"))) {
+ r = queue_if_no_path(m, 1, 0);
+ goto out;
+ } else if (!strnicmp(argv[0], MESG_STR("fail_if_no_path"))) {
+ r = queue_if_no_path(m, 0, 0);
+ goto out;
+ }
}
- if (argc != 2)
- goto error;
+ if (argc != 2) {
+ DMWARN("Unrecognised multipath message received.");
+ goto out;
+ }
- if (!strnicmp(argv[0], MESG_STR("disable_group")))
- return bypass_pg_num(m, argv[1], 1);
- else if (!strnicmp(argv[0], MESG_STR("enable_group")))
- return bypass_pg_num(m, argv[1], 0);
- else if (!strnicmp(argv[0], MESG_STR("switch_group")))
- return switch_pg_num(m, argv[1]);
- else if (!strnicmp(argv[0], MESG_STR("reinstate_path")))
+ if (!strnicmp(argv[0], MESG_STR("disable_group"))) {
+ r = bypass_pg_num(m, argv[1], 1);
+ goto out;
+ } else if (!strnicmp(argv[0], MESG_STR("enable_group"))) {
+ r = bypass_pg_num(m, argv[1], 0);
+ goto out;
+ } else if (!strnicmp(argv[0], MESG_STR("switch_group"))) {
+ r = switch_pg_num(m, argv[1]);
+ goto out;
+ } else if (!strnicmp(argv[0], MESG_STR("reinstate_path")))
action = reinstate_path;
else if (!strnicmp(argv[0], MESG_STR("fail_path")))
action = fail_path;
- else
- goto error;
+ else {
+ DMWARN("Unrecognised multipath message received.");
+ goto out;
+ }
- r = dm_get_device(ti, argv[1], ti->begin, ti->len,
- dm_table_get_mode(ti->table), &dev);
+ r = dm_get_device(ti, argv[1], dm_table_get_mode(ti->table), &dev);
if (r) {
DMWARN("message: error getting device %s",
argv[1]);
- return -EINVAL;
+ goto out;
}
r = action_dev(m, dev, action);
dm_put_device(ti, dev);
+out:
+ mutex_unlock(&m->work_mutex);
return r;
-
-error:
- DMWARN("Unrecognised multipath message received.");
- return -EINVAL;
}
static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
spin_lock_irqsave(&m->lock, flags);
if (!m->current_pgpath)
- __choose_pgpath(m);
+ __choose_pgpath(m, 0);
if (m->current_pgpath) {
bdev = m->current_pgpath->path.dev->bdev;
return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg);
}
+static int multipath_iterate_devices(struct dm_target *ti,
+ iterate_devices_callout_fn fn, void *data)
+{
+ struct multipath *m = ti->private;
+ struct priority_group *pg;
+ struct pgpath *p;
+ int ret = 0;
+
+ list_for_each_entry(pg, &m->priority_groups, list) {
+ list_for_each_entry(p, &pg->pgpaths, list) {
+ ret = fn(ti, p->path.dev, ti->begin, ti->len, data);
+ if (ret)
+ goto out;
+ }
+ }
+
+out:
+ return ret;
+}
+
+static int __pgpath_busy(struct pgpath *pgpath)
+{
+ struct request_queue *q = bdev_get_queue(pgpath->path.dev->bdev);
+
+ return dm_underlying_device_busy(q);
+}
+
+/*
+ * We return "busy", only when we can map I/Os but underlying devices
+ * are busy (so even if we map I/Os now, the I/Os will wait on
+ * the underlying queue).
+ * In other words, if we want to kill I/Os or queue them inside us
+ * due to map unavailability, we don't return "busy". Otherwise,
+ * dm core won't give us the I/Os and we can't do what we want.
+ */
+static int multipath_busy(struct dm_target *ti)
+{
+ int busy = 0, has_active = 0;
+ struct multipath *m = ti->private;
+ struct priority_group *pg;
+ struct pgpath *pgpath;
+ unsigned long flags;
+
+ spin_lock_irqsave(&m->lock, flags);
+
+ /* Guess which priority_group will be used at next mapping time */
+ if (unlikely(!m->current_pgpath && m->next_pg))
+ pg = m->next_pg;
+ else if (likely(m->current_pg))
+ pg = m->current_pg;
+ else
+ /*
+ * We don't know which pg will be used at next mapping time.
+ * We don't call __choose_pgpath() here to avoid to trigger
+ * pg_init just by busy checking.
+ * So we don't know whether underlying devices we will be using
+ * at next mapping time are busy or not. Just try mapping.
+ */
+ goto out;
+
+ /*
+ * If there is one non-busy active path at least, the path selector
+ * will be able to select it. So we consider such a pg as not busy.
+ */
+ busy = 1;
+ list_for_each_entry(pgpath, &pg->pgpaths, list)
+ if (pgpath->is_active) {
+ has_active = 1;
+
+ if (!__pgpath_busy(pgpath)) {
+ busy = 0;
+ break;
+ }
+ }
+
+ if (!has_active)
+ /*
+ * No active path in this pg, so this pg won't be used and
+ * the current_pg will be changed at next mapping time.
+ * We need to try mapping to determine it.
+ */
+ busy = 0;
+
+out:
+ spin_unlock_irqrestore(&m->lock, flags);
+
+ return busy;
+}
+
/*-----------------------------------------------------------------
* Module setup
*---------------------------------------------------------------*/
static struct target_type multipath_target = {
.name = "multipath",
- .version = {1, 0, 5},
+ .version = {1, 1, 1},
.module = THIS_MODULE,
.ctr = multipath_ctr,
.dtr = multipath_dtr,
- .map = multipath_map,
- .end_io = multipath_end_io,
+ .map_rq = multipath_map,
+ .rq_end_io = multipath_end_io,
.presuspend = multipath_presuspend,
+ .postsuspend = multipath_postsuspend,
.resume = multipath_resume,
.status = multipath_status,
.message = multipath_message,
.ioctl = multipath_ioctl,
+ .iterate_devices = multipath_iterate_devices,
+ .busy = multipath_busy,
};
static int __init dm_multipath_init(void)
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff