[PATCH 4.5 024/200] dm cache metadata: fix cmd_read_lock() acquiring write lock

Greg Kroah-Hartman
2016-05-03T01:24:38Z

From: Ahmed Samy <f.fallen45@gmail.com>

commit 6545b60baaf880b0cd29a5e89dbe745a06027e89 upstream.

Commit 9567366fefdd ("dm cache metadata: fix READ_LOCK macros and
cleanup WRITE_LOCK macros") uses down_write() instead of down_read() in
cmd_read_lock(), yet up_read() is used to release the lock in
READ_UNLOCK(). Fix it.

Fixes: 9567366fefdd ("dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros")
Signed-off-by: Ahmed Samy <f.fallen45@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/md/dm-cache-metadata.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/md/dm-cache-metadata.c
+++ b/drivers/md/dm-cache-metadata.c
@@ -894,9 +894,9 @@ static bool cmd_write_lock(struct dm_cac

static bool cmd_read_lock(struct dm_cache_metadata *cmd)
{
- down_write(&cmd->root_lock);
+ down_read(&cmd->root_lock);
if (cmd->fail_io) {
- up_write(&cmd->root_lock);
+ up_read(&cmd->root_lock);
return false;
}
return true;