From 583024d248f486e21479d1912aa2093565455770 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Tue, 28 Oct 2014 20:58:45 -0400 Subject: dm thin: suspend/resume active thin devices when reloading thin-pool Before this change it was expected that userspace would first suspend all active thin devices, reload/resize the thin-pool target, then resume all active thin devices. Now the thin-pool suspend/resume will trigger the suspend/resume of all active thins via appropriate calls to dm_internal_suspend and dm_internal_resume. Store the mapped_device for each thin device in struct thin_c to make these calls possible. Signed-off-by: Mike Snitzer Acked-by: Joe Thornber --- drivers/md/dm-thin.c | 40 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 38 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index f1b53e31d868..e9e9584fe769 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -292,6 +292,8 @@ struct thin_c { struct pool *pool; struct dm_thin_device *td; + struct mapped_device *thin_md; + bool requeue_mode:1; spinlock_t lock; struct list_head deferred_cells; @@ -3113,19 +3115,48 @@ static int pool_preresume(struct dm_target *ti) return 0; } +static void pool_suspend_active_thins(struct pool *pool) +{ + struct thin_c *tc; + + /* Suspend all active thin devices */ + tc = get_first_thin(pool); + while (tc) { + dm_internal_suspend_noflush(tc->thin_md); + tc = get_next_thin(pool, tc); + } +} + +static void pool_resume_active_thins(struct pool *pool) +{ + struct thin_c *tc; + + /* Resume all active thin devices */ + tc = get_first_thin(pool); + while (tc) { + dm_internal_resume(tc->thin_md); + tc = get_next_thin(pool, tc); + } +} + static void pool_resume(struct dm_target *ti) { struct pool_c *pt = ti->private; struct pool *pool = pt->pool; unsigned long flags; + /* + * Must requeue active_thins' bios and then resume + * active_thins _before_ clearing 'suspend' flag. + */ + requeue_bios(pool); + pool_resume_active_thins(pool); + spin_lock_irqsave(&pool->lock, flags); pool->low_water_triggered = false; pool->suspended = false; spin_unlock_irqrestore(&pool->lock, flags); - requeue_bios(pool); - do_waker(&pool->waker.work); } @@ -3138,6 +3169,8 @@ static void pool_presuspend(struct dm_target *ti) spin_lock_irqsave(&pool->lock, flags); pool->suspended = true; spin_unlock_irqrestore(&pool->lock, flags); + + pool_suspend_active_thins(pool); } static void pool_presuspend_undo(struct dm_target *ti) @@ -3146,6 +3179,8 @@ static void pool_presuspend_undo(struct dm_target *ti) struct pool *pool = pt->pool; unsigned long flags; + pool_resume_active_thins(pool); + spin_lock_irqsave(&pool->lock, flags); pool->suspended = false; spin_unlock_irqrestore(&pool->lock, flags); @@ -3703,6 +3738,7 @@ static int thin_ctr(struct dm_target *ti, unsigned argc, char **argv) r = -ENOMEM; goto out_unlock; } + tc->thin_md = dm_table_get_md(ti->table); spin_lock_init(&tc->lock); INIT_LIST_HEAD(&tc->deferred_cells); bio_list_init(&tc->deferred_bio_list); -- cgit v1.2.3