diff options
author | David Woodhouse <dwmw2@shinybook.infradead.org> | 2005-07-13 15:25:59 +0100 |
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committer | David Woodhouse <dwmw2@shinybook.infradead.org> | 2005-07-13 15:25:59 +0100 |
commit | 30beab1491f0b96b2f23d3fb68af01fd921a16d8 (patch) | |
tree | c580bdc0846269fbb10feeda901ecec1a48ee2ef /drivers/md/dm-mpath.c | |
parent | 21af6c4f2aa5f63138871b4ddd77d7ebf2588c9d (diff) | |
parent | c32511e2718618f0b53479eb36e07439aa363a74 (diff) |
Merge with /shiny/git/linux-2.6/.git
Diffstat (limited to 'drivers/md/dm-mpath.c')
-rw-r--r-- | drivers/md/dm-mpath.c | 68 |
1 files changed, 43 insertions, 25 deletions
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index 0c1b8520ef8..785806bdb24 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -63,6 +63,7 @@ struct multipath { 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; @@ -72,7 +73,7 @@ struct multipath { 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; @@ -304,11 +305,12 @@ static int map_io(struct multipath *m, struct bio *bio, struct mpath_io *mpio, 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; @@ -333,8 +335,9 @@ static int queue_if_no_path(struct multipath *m, unsigned queue_if_no_path) spin_lock_irqsave(&m->lock, flags); + m->saved_queue_if_no_path = m->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); @@ -379,25 +382,31 @@ static void process_queued_ios(void *data) { 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) @@ -752,6 +761,8 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc, static void multipath_dtr(struct dm_target *ti) { struct multipath *m = (struct multipath *) ti->private; + + flush_workqueue(kmultipathd); free_multipath(m); } @@ -765,6 +776,9 @@ static int multipath_map(struct dm_target *ti, struct bio *bio, struct mpath_io *mpio; struct multipath *m = (struct multipath *) ti->private; + if (bio_barrier(bio)) + return -EOPNOTSUPP; + mpio = mempool_alloc(m->mpio_pool, GFP_NOIO); dm_bio_record(&mpio->details, bio); @@ -837,7 +851,7 @@ static int reinstate_path(struct pgpath *pgpath) 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); @@ -963,12 +977,13 @@ void dm_pg_init_complete(struct path *path, unsigned err_flags) 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); } @@ -988,9 +1003,12 @@ static int do_end_io(struct multipath *m, struct bio *bio, if ((error == -EWOULDBLOCK) && bio_rw_ahead(bio)) return error; + if (error == -EOPNOTSUPP) + return error; + spin_lock(&m->lock); if (!m->nr_valid_paths) { - if (!m->queue_if_no_path || m->suspended) { + if (!m->queue_if_no_path) { spin_unlock(&m->lock); return -EIO; } else { @@ -1051,27 +1069,27 @@ static int multipath_end_io(struct dm_target *ti, struct bio *bio, /* * 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); } +/* + * 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); } |