From 33184048dc4f9d5550d3b6a88c8e0ff92033eb6e Mon Sep 17 00:00:00 2001 From: Jonathan E Brassow Date: Wed, 8 Nov 2006 17:44:44 -0800 Subject: [PATCH] [PATCH] dm: raid1: fix waiting for io on suspend All device-mapper targets must complete outstanding I/O before suspending. The mirror target generates I/O in its recovery phase and fails to wait for it. It needs to be tracked so we can ensure that it has completed before we suspend. [akpm@osdl.org: cleanup] Signed-off-by: Jonathan E Brassow Signed-off-by: Alasdair G Kergon Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm-raid1.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c index 659224cb7c5..48a653b3f51 100644 --- a/drivers/md/dm-raid1.c +++ b/drivers/md/dm-raid1.c @@ -24,6 +24,7 @@ static struct workqueue_struct *_kmirrord_wq; static struct work_struct _kmirrord_work; +static DECLARE_WAIT_QUEUE_HEAD(_kmirrord_recovery_stopped); static inline void wake(void) { @@ -83,6 +84,7 @@ struct region_hash { struct list_head *buckets; spinlock_t region_lock; + atomic_t recovery_in_flight; struct semaphore recovery_count; struct list_head clean_regions; struct list_head quiesced_regions; @@ -191,6 +193,7 @@ static int rh_init(struct region_hash *rh, struct mirror_set *ms, spin_lock_init(&rh->region_lock); sema_init(&rh->recovery_count, 0); + atomic_set(&rh->recovery_in_flight, 0); INIT_LIST_HEAD(&rh->clean_regions); INIT_LIST_HEAD(&rh->quiesced_regions); INIT_LIST_HEAD(&rh->recovered_regions); @@ -382,6 +385,8 @@ static void rh_update_states(struct region_hash *rh) rh->log->type->clear_region(rh->log, reg->key); rh->log->type->complete_resync_work(rh->log, reg->key, 1); dispatch_bios(rh->ms, ®->delayed_bios); + if (atomic_dec_and_test(&rh->recovery_in_flight)) + wake_up_all(&_kmirrord_recovery_stopped); up(&rh->recovery_count); mempool_free(reg, rh->region_pool); } @@ -502,11 +507,21 @@ static int __rh_recovery_prepare(struct region_hash *rh) static void rh_recovery_prepare(struct region_hash *rh) { - while (!down_trylock(&rh->recovery_count)) + /* Extra reference to avoid race with rh_stop_recovery */ + atomic_inc(&rh->recovery_in_flight); + + while (!down_trylock(&rh->recovery_count)) { + atomic_inc(&rh->recovery_in_flight); if (__rh_recovery_prepare(rh) <= 0) { + atomic_dec(&rh->recovery_in_flight); up(&rh->recovery_count); break; } + } + + /* Drop the extra reference */ + if (atomic_dec_and_test(&rh->recovery_in_flight)) + wake_up_all(&_kmirrord_recovery_stopped); } /* @@ -1177,6 +1192,11 @@ static void mirror_postsuspend(struct dm_target *ti) struct dirty_log *log = ms->rh.log; rh_stop_recovery(&ms->rh); + + /* Wait for all I/O we generated to complete */ + wait_event(_kmirrord_recovery_stopped, + !atomic_read(&ms->rh.recovery_in_flight)); + if (log->type->suspend && log->type->suspend(log)) /* FIXME: need better error handling */ DMWARN("log suspend failed"); -- 2.41.1