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 */
unsigned nr_valid_paths; /* Total number of usable paths */
struct pgpath *current_pgpath;
unsigned queue_io; /* Must we queue all I/O? */
unsigned queue_if_no_path; /* Queue I/O if last path fails? */
- unsigned suspended; /* Has dm core suspended our I/O? */
+ unsigned saved_queue_if_no_path;/* Saved state during suspension */
struct work_struct process_queued_ios;
struct bio_list queued_ios;
m->queue_io = 1;
INIT_WORK(&m->process_queued_ios, process_queued_ios, m);
INIT_WORK(&m->trigger_event, trigger_event, m);
- m->mpio_pool = mempool_create(MIN_IOS, mempool_alloc_slab,
- mempool_free_slab, _mpio_cache);
+ m->mpio_pool = mempool_create_slab_pool(MIN_IOS, _mpio_cache);
if (!m->mpio_pool) {
kfree(m);
return NULL;
m->queue_size--;
if ((pgpath && m->queue_io) ||
- (!pgpath && m->queue_if_no_path && !m->suspended)) {
+ (!pgpath && m->queue_if_no_path)) {
/* Queue for the daemon to resubmit */
bio_list_add(&m->queued_ios, bio);
m->queue_size++;
- if (m->pg_init_required || !m->queue_io)
+ if ((m->pg_init_required && !m->pg_init_in_progress) ||
+ !m->queue_io)
queue_work(kmultipathd, &m->process_queued_ios);
pgpath = NULL;
r = 0;
/*
* If we run out of usable paths, should we queue I/O or error it?
*/
-static int queue_if_no_path(struct multipath *m, unsigned queue_if_no_path)
+static int queue_if_no_path(struct multipath *m, unsigned queue_if_no_path,
+ unsigned save_old_value)
{
unsigned long flags;
spin_lock_irqsave(&m->lock, flags);
+ if (save_old_value)
+ m->saved_queue_if_no_path = m->queue_if_no_path;
+ 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)
+ if (!m->queue_if_no_path && m->queue_size)
queue_work(kmultipathd, &m->process_queued_ios);
spin_unlock_irqrestore(&m->lock, flags);
{
struct multipath *m = (struct multipath *) data;
struct hw_handler *hwh = &m->hw_handler;
- struct pgpath *pgpath;
- unsigned init_required, must_queue = 0;
+ struct pgpath *pgpath = NULL;
+ unsigned init_required = 0, must_queue = 1;
unsigned long flags;
spin_lock_irqsave(&m->lock, flags);
+ if (!m->queue_size)
+ goto out;
+
if (!m->current_pgpath)
__choose_pgpath(m);
pgpath = m->current_pgpath;
- if ((pgpath && m->queue_io) ||
- (!pgpath && m->queue_if_no_path && !m->suspended))
- must_queue = 1;
+ if ((pgpath && !m->queue_io) ||
+ (!pgpath && !m->queue_if_no_path))
+ must_queue = 0;
- init_required = m->pg_init_required;
- if (init_required)
+ if (m->pg_init_required && !m->pg_init_in_progress) {
m->pg_init_required = 0;
+ m->pg_init_in_progress = 1;
+ init_required = 1;
+ }
+out:
spin_unlock_irqrestore(&m->lock, flags);
if (init_required)
return 0;
if (!strnicmp(shift(as), MESG_STR("queue_if_no_path")))
- return queue_if_no_path(m, 1);
+ return queue_if_no_path(m, 1, 0);
else {
ti->error = "Unrecognised multipath feature request";
return -EINVAL;
pgpath->path.is_active = 1;
m->current_pgpath = NULL;
- if (!m->nr_valid_paths++)
+ if (!m->nr_valid_paths++ && m->queue_size)
queue_work(kmultipathd, &m->process_queued_ios);
queue_work(kmultipathd, &m->trigger_event);
bypass_pg(m, pg, 1);
spin_lock_irqsave(&m->lock, flags);
- if (!err_flags)
- m->queue_io = 0;
- else {
+ if (err_flags) {
m->current_pgpath = NULL;
m->current_pg = NULL;
- }
+ } else if (!m->pg_init_required)
+ m->queue_io = 0;
+
+ m->pg_init_in_progress = 0;
queue_work(kmultipathd, &m->process_queued_ios);
spin_unlock_irqrestore(&m->lock, flags);
}
{
struct hw_handler *hwh = &m->hw_handler;
unsigned err_flags = MP_FAIL_PATH; /* Default behavior */
+ unsigned long flags;
if (!error)
return 0; /* I/O complete */
if (error == -EOPNOTSUPP)
return error;
- spin_lock(&m->lock);
+ spin_lock_irqsave(&m->lock, flags);
if (!m->nr_valid_paths) {
- if (!m->queue_if_no_path || m->suspended) {
- spin_unlock(&m->lock);
+ if (!m->queue_if_no_path) {
+ spin_unlock_irqrestore(&m->lock, flags);
return -EIO;
} else {
- spin_unlock(&m->lock);
+ spin_unlock_irqrestore(&m->lock, flags);
goto requeue;
}
}
- spin_unlock(&m->lock);
+ spin_unlock_irqrestore(&m->lock, flags);
if (hwh->type && hwh->type->error)
err_flags = hwh->type->error(hwh, bio);
dm_bio_restore(&mpio->details, bio);
/* queue for the daemon to resubmit or fail */
- spin_lock(&m->lock);
+ 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);
- spin_unlock(&m->lock);
+ spin_unlock_irqrestore(&m->lock, flags);
return 1; /* io not complete */
}
/*
* Suspend can't complete until all the I/O is processed so if
- * the last path failed we will now error any queued I/O.
+ * the last path fails we must error any remaining I/O.
+ * Note that if the freeze_bdev fails while suspending, the
+ * queue_if_no_path state is lost - userspace should reset it.
*/
static void multipath_presuspend(struct dm_target *ti)
{
struct multipath *m = (struct multipath *) ti->private;
- unsigned long flags;
- spin_lock_irqsave(&m->lock, flags);
- m->suspended = 1;
- if (m->queue_if_no_path)
- queue_work(kmultipathd, &m->process_queued_ios);
- spin_unlock_irqrestore(&m->lock, flags);
+ queue_if_no_path(m, 0, 1);
}
+/*
+ * Restore the queue_if_no_path setting.
+ */
static void multipath_resume(struct dm_target *ti)
{
struct multipath *m = (struct multipath *) ti->private;
unsigned long flags;
spin_lock_irqsave(&m->lock, flags);
- m->suspended = 0;
+ m->queue_if_no_path = m->saved_queue_if_no_path;
spin_unlock_irqrestore(&m->lock, flags);
}
if (argc == 1) {
if (!strnicmp(argv[0], MESG_STR("queue_if_no_path")))
- return queue_if_no_path(m, 1);
+ 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);
+ return queue_if_no_path(m, 0, 0);
}
if (argc != 2)