From 695368ac3302174531429a90d55c3f7f9b83906e Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Tue, 3 Oct 2006 01:15:31 -0700 Subject: [PATCH] [PATCH] dm snapshot: fix freeing pending exception If a snapshot became invalid while there are outstanding pending_exceptions, when pending_complete() processes each one it forgets to remove the corresponding exception from its exception table before freeing it. Fix this by moving the 'out:' label up one statement so that remove_exception() is always called. Then __invalidate_exception() no longer needs to call it and its 'pe' argument become superfluous. Signed-off-by: Alasdair G Kergon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm-snap.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index 638c8d90da0..5281e009407 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -631,8 +631,7 @@ static void error_bios(struct bio *bio) } } -static void __invalidate_snapshot(struct dm_snapshot *s, - struct pending_exception *pe, int err) +static void __invalidate_snapshot(struct dm_snapshot *s, int err) { if (!s->valid) return; @@ -642,9 +641,6 @@ static void __invalidate_snapshot(struct dm_snapshot *s, else if (err == -ENOMEM) DMERR("Invalidating snapshot: Unable to allocate exception."); - if (pe) - remove_exception(&pe->e); - if (s->store.drop_snapshot) s->store.drop_snapshot(&s->store); @@ -701,7 +697,7 @@ static void pending_complete(struct pending_exception *pe, int success) if (!success) { /* Read/write error - snapshot is unusable */ down_write(&s->lock); - __invalidate_snapshot(s, pe, -EIO); + __invalidate_snapshot(s, -EIO); error = 1; goto out; } @@ -709,7 +705,7 @@ static void pending_complete(struct pending_exception *pe, int success) e = alloc_exception(); if (!e) { down_write(&s->lock); - __invalidate_snapshot(s, pe, -ENOMEM); + __invalidate_snapshot(s, -ENOMEM); error = 1; goto out; } @@ -727,9 +723,9 @@ static void pending_complete(struct pending_exception *pe, int success) * in-flight exception from the list. */ insert_exception(&s->complete, e); - remove_exception(&pe->e); out: + remove_exception(&pe->e); snapshot_bios = bio_list_get(&pe->snapshot_bios); origin_bios = put_pending_exception(pe); @@ -909,7 +905,7 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio, if (bio_rw(bio) == WRITE) { pe = __find_pending_exception(s, bio); if (!pe) { - __invalidate_snapshot(s, pe, -ENOMEM); + __invalidate_snapshot(s, -ENOMEM); r = -EIO; goto out_unlock; } @@ -1035,7 +1031,7 @@ static int __origin_write(struct list_head *snapshots, struct bio *bio) pe = __find_pending_exception(snap, bio); if (!pe) { - __invalidate_snapshot(snap, pe, -ENOMEM); + __invalidate_snapshot(snap, -ENOMEM); goto next_snapshot; } -- 2.41.1