unsigned pg_init_count; /* Number of times pg_init called */
unsigned pg_init_delay_msecs; /* Number of msecs before pg_init retry */
- unsigned queue_size;
- struct work_struct process_queued_ios;
- struct list_head queued_ios;
-
struct work_struct trigger_event;
/*
static struct kmem_cache *_mpio_cache;
static struct workqueue_struct *kmultipathd, *kmpath_handlerd;
-static void process_queued_ios(struct work_struct *work);
static void trigger_event(struct work_struct *work);
static void activate_path(struct work_struct *work);
+static int __pgpath_busy(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;
m->pg_init_delay_msecs = DM_PG_INIT_DELAY_DEFAULT;
- 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);
* Path selection
*-----------------------------------------------*/
-static void __pg_init_all_paths(struct multipath *m)
+static int __pg_init_all_paths(struct multipath *m)
{
struct pgpath *pgpath;
unsigned long pg_init_delay = 0;
+ if (m->pg_init_in_progress || m->pg_init_disabled)
+ return 0;
+
m->pg_init_count++;
m->pg_init_required = 0;
+
+ /* Check here to reset pg_init_required */
+ if (!m->current_pg)
+ return 0;
+
if (m->pg_init_delay_retry)
pg_init_delay = msecs_to_jiffies(m->pg_init_delay_msecs != DM_PG_INIT_DELAY_DEFAULT ?
m->pg_init_delay_msecs : DM_PG_INIT_DELAY_MSECS);
pg_init_delay))
m->pg_init_in_progress++;
}
+ return m->pg_init_in_progress;
}
static void __switch_pg(struct multipath *m, struct pgpath *pgpath)
*/
static int __must_push_back(struct multipath *m)
{
- return (m->queue_if_no_path != m->saved_queue_if_no_path &&
- dm_noflush_suspending(m->ti));
+ return (m->queue_if_no_path ||
+ (m->queue_if_no_path != m->saved_queue_if_no_path &&
+ dm_noflush_suspending(m->ti)));
}
-static int map_io(struct multipath *m, struct request *clone,
- union map_info *map_context, unsigned was_queued)
+#define pg_ready(m) (!(m)->queue_io && !(m)->pg_init_required)
+
+/*
+ * Map cloned requests
+ */
+static int multipath_map(struct dm_target *ti, struct request *clone,
+ union map_info *map_context)
{
- int r = DM_MAPIO_REMAPPED;
+ struct multipath *m = (struct multipath *) ti->private;
+ int r = DM_MAPIO_REQUEUE;
size_t nr_bytes = blk_rq_bytes(clone);
unsigned long flags;
struct pgpath *pgpath;
struct block_device *bdev;
- struct dm_mpath_io *mpio = map_context->ptr;
+ struct dm_mpath_io *mpio;
spin_lock_irqsave(&m->lock, flags);
pgpath = m->current_pgpath;
- if (was_queued)
- m->queue_size--;
-
- if (m->pg_init_required) {
- if (!m->pg_init_in_progress)
- queue_work(kmultipathd, &m->process_queued_ios);
- r = DM_MAPIO_REQUEUE;
- } else if ((pgpath && m->queue_io) ||
- (!pgpath && m->queue_if_no_path)) {
- /* Queue for the daemon to resubmit */
- list_add_tail(&clone->queuelist, &m->queued_ios);
- m->queue_size++;
- if (!m->queue_io)
- queue_work(kmultipathd, &m->process_queued_ios);
- pgpath = NULL;
- r = DM_MAPIO_SUBMITTED;
- } 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 */
+ if (!pgpath) {
+ if (!__must_push_back(m))
+ r = -EIO; /* Failed */
+ goto out_unlock;
+ }
+ if (!pg_ready(m)) {
+ __pg_init_all_paths(m);
+ goto out_unlock;
+ }
+ if (set_mapinfo(m, map_context) < 0)
+ /* ENOMEM, requeue */
+ goto out_unlock;
+ bdev = pgpath->path.dev->bdev;
+ clone->q = bdev_get_queue(bdev);
+ clone->rq_disk = bdev->bd_disk;
+ clone->cmd_flags |= REQ_FAILFAST_TRANSPORT;
+ mpio = map_context->ptr;
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,
+ if (pgpath->pg->ps.type->start_io)
+ pgpath->pg->ps.type->start_io(&pgpath->pg->ps,
+ &pgpath->path,
nr_bytes);
+ r = DM_MAPIO_REMAPPED;
+out_unlock:
spin_unlock_irqrestore(&m->lock, flags);
return r;
else
m->saved_queue_if_no_path = queue_if_no_path;
m->queue_if_no_path = queue_if_no_path;
- if (!m->queue_if_no_path && m->queue_size)
- queue_work(kmultipathd, &m->process_queued_ios);
+ if (!m->queue_if_no_path)
+ dm_table_run_md_queue_async(m->ti->table);
spin_unlock_irqrestore(&m->lock, flags);
return 0;
}
-/*-----------------------------------------------------------------
- * The multipath daemon is responsible for resubmitting queued ios.
- *---------------------------------------------------------------*/
-
-static void dispatch_queued_ios(struct multipath *m)
-{
- int r;
- unsigned long flags;
- union map_info *info;
- struct request *clone, *n;
- LIST_HEAD(cl);
-
- spin_lock_irqsave(&m->lock, flags);
- list_splice_init(&m->queued_ios, &cl);
- spin_unlock_irqrestore(&m->lock, flags);
-
- list_for_each_entry_safe(clone, n, &cl, queuelist) {
- list_del_init(&clone->queuelist);
-
- info = dm_get_rq_mapinfo(clone);
-
- r = map_io(m, clone, info, 1);
- if (r < 0) {
- clear_mapinfo(m, info);
- dm_kill_unmapped_request(clone, r);
- } else if (r == DM_MAPIO_REMAPPED)
- dm_dispatch_request(clone);
- else if (r == DM_MAPIO_REQUEUE) {
- clear_mapinfo(m, info);
- dm_requeue_unmapped_request(clone);
- }
- }
-}
-
-static void process_queued_ios(struct work_struct *work)
-{
- struct multipath *m =
- container_of(work, struct multipath, process_queued_ios);
- struct pgpath *pgpath = NULL;
- unsigned must_queue = 1;
- unsigned long flags;
-
- spin_lock_irqsave(&m->lock, flags);
-
- if (!m->current_pgpath)
- __choose_pgpath(m, 0);
-
- pgpath = m->current_pgpath;
-
- if ((pgpath && !m->queue_io) ||
- (!pgpath && !m->queue_if_no_path))
- must_queue = 0;
-
- if (m->pg_init_required && !m->pg_init_in_progress && pgpath &&
- !m->pg_init_disabled)
- __pg_init_all_paths(m);
-
- spin_unlock_irqrestore(&m->lock, flags);
- if (!must_queue)
- dispatch_queued_ios(m);
-}
-
/*
* An event is triggered whenever a path is taken out of use.
* Includes path failure and PG bypass.
free_multipath(m);
}
-/*
- * Map cloned requests
- */
-static int multipath_map(struct dm_target *ti, struct request *clone,
- union map_info *map_context)
-{
- int r;
- struct multipath *m = (struct multipath *) ti->private;
-
- if (set_mapinfo(m, map_context) < 0)
- /* ENOMEM, requeue */
- return DM_MAPIO_REQUEUE;
-
- clone->cmd_flags |= REQ_FAILFAST_TRANSPORT;
- r = map_io(m, clone, map_context, 0);
- if (r < 0 || r == DM_MAPIO_REQUEUE)
- clear_mapinfo(m, map_context);
-
- return r;
-}
-
/*
* Take a path out of use.
*/
pgpath->is_active = 1;
- if (!m->nr_valid_paths++ && m->queue_size) {
+ if (!m->nr_valid_paths++) {
m->current_pgpath = NULL;
- queue_work(kmultipathd, &m->process_queued_ios);
+ dm_table_run_md_queue_async(m->ti->table);
} else if (m->hw_handler_name && (m->current_pg == pgpath->pg)) {
if (queue_work(kmpath_handlerd, &pgpath->activate_path.work))
m->pg_init_in_progress++;
/* Activations of other paths are still on going */
goto out;
- if (!m->pg_init_required)
- m->queue_io = 0;
-
- m->pg_init_delay_retry = delay_retry;
- queue_work(kmultipathd, &m->process_queued_ios);
+ if (m->pg_init_required) {
+ m->pg_init_delay_retry = delay_retry;
+ if (__pg_init_all_paths(m))
+ goto out;
+ }
+ m->queue_io = 0;
/*
* Wake up any thread waiting to suspend.
struct pgpath *pgpath =
container_of(work, struct pgpath, activate_path.work);
- scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev),
- pg_init_done, pgpath);
+ if (pgpath->is_active)
+ scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev),
+ pg_init_done, pgpath);
+ else
+ pg_init_done(pgpath, SCSI_DH_DEV_OFFLINED);
}
static int noretry_error(int error)
/* Features */
if (type == STATUSTYPE_INFO)
- DMEMIT("2 %u %u ", m->queue_size, m->pg_init_count);
+ DMEMIT("2 %u %u ", m->queue_io, m->pg_init_count);
else {
DMEMIT("%u ", m->queue_if_no_path +
(m->pg_init_retries > 0) * 2 +
}
if (argc != 2) {
- DMWARN("Unrecognised multipath message received.");
+ DMWARN("Invalid multipath message arguments. Expected 2 arguments, got %d.", argc);
goto out;
}
else if (!strcasecmp(argv[0], "fail_path"))
action = fail_path;
else {
- DMWARN("Unrecognised multipath message received.");
+ DMWARN("Unrecognised multipath message received: %s", argv[0]);
goto out;
}
r = err;
}
- if (r == -ENOTCONN && !fatal_signal_pending(current))
- queue_work(kmultipathd, &m->process_queued_ios);
+ if (r == -ENOTCONN && !fatal_signal_pending(current)) {
+ spin_lock_irqsave(&m->lock, flags);
+ if (!m->current_pg) {
+ /* Path status changed, redo selection */
+ __choose_pgpath(m, 0);
+ }
+ if (m->pg_init_required)
+ __pg_init_all_paths(m);
+ spin_unlock_irqrestore(&m->lock, flags);
+ dm_table_run_md_queue_async(m->ti->table);
+ }
return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg);
}
spin_lock_irqsave(&m->lock, flags);
/* pg_init in progress, requeue until done */
- if (m->pg_init_in_progress) {
+ if (!pg_ready(m)) {
busy = 1;
goto out;
}
*---------------------------------------------------------------*/
static struct target_type multipath_target = {
.name = "multipath",
- .version = {1, 6, 0},
+ .version = {1, 7, 0},
.module = THIS_MODULE,
.ctr = multipath_ctr,
.dtr = multipath_dtr,
projects / karo-tx-linux.git / blobdiff