dm thin: always fallback the pool mode if commit fails

Rename commit_or_fallback() to commit().  Now all previous calls to
commit() will trigger the pool mode to fallback if the commit fails.

Also, check the error returned from commit() in alloc_data_block().

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org

1 files changed, 15 insertions, 22 deletions

diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 44ee489f4a6e..af79bae5ab74 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -883,32 +883,23 @@ static void schedule_zero(struct thin_c *tc, dm_block_t virt_block,
         }
 }
 
-static int commit(struct pool *pool)
-{
-        int r;
-
-        r = dm_pool_commit_metadata(pool->pmd);
-        if (r)
-                DMERR_LIMIT("%s: commit failed: error = %d",
-                            dm_device_name(pool->pool_md), r);
-
-        return r;
-}
-
 /*
  * A non-zero return indicates read_only or fail_io mode.
  * Many callers don't care about the return value.
  */
-static int commit_or_fallback(struct pool *pool)
+static int commit(struct pool *pool)
 {
         int r;
 
         if (get_pool_mode(pool) != PM_WRITE)
                 return -EINVAL;
 
-        r = commit(pool);
-        if (r)
+        r = dm_pool_commit_metadata(pool->pmd);
+        if (r) {
+                DMERR_LIMIT("%s: dm_pool_commit_metadata failed: error = %d",
+                            dm_device_name(pool->pool_md), r);
                 set_pool_mode(pool, PM_READ_ONLY);
+        }
 
         return r;
 }
@@ -945,7 +936,9 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result)
                  * Try to commit to see if that will free up some
                  * more space.
                  */
-                (void) commit_or_fallback(pool);
+                r = commit(pool);
+                if (r)
+                        return r;
 
                 r = dm_pool_get_free_block_count(pool->pmd, &free_blocks);
                 if (r)
@@ -1359,7 +1352,7 @@ static void process_deferred_bios(struct pool *pool)
         if (bio_list_empty(&bios) && !need_commit_due_to_time(pool))
                 return;
 
-        if (commit_or_fallback(pool)) {
+        if (commit(pool)) {
                 while ((bio = bio_list_pop(&bios)))
                         bio_io_error(bio);
                 return;
@@ -2276,7 +2269,7 @@ static int pool_preresume(struct dm_target *ti)
                 return r;
 
         if (need_commit1 || need_commit2)
-                (void) commit_or_fallback(pool);
+                (void) commit(pool);
 
         return 0;
 }
@@ -2303,7 +2296,7 @@ static void pool_postsuspend(struct dm_target *ti)
 
         cancel_delayed_work(&pool->waker);
         flush_workqueue(pool->wq);
-        (void) commit_or_fallback(pool);
+        (void) commit(pool);
 }
 
 static int check_arg_count(unsigned argc, unsigned args_required)
@@ -2437,7 +2430,7 @@ static int process_reserve_metadata_snap_mesg(unsigned argc, char **argv, struct
         if (r)
                 return r;
 
-        (void) commit_or_fallback(pool);
+        (void) commit(pool);
 
         r = dm_pool_reserve_metadata_snap(pool->pmd);
         if (r)
@@ -2499,7 +2492,7 @@ static int pool_message(struct dm_target *ti, unsigned argc, char **argv)
                 DMWARN("Unrecognised thin pool target message received: %s", argv[0]);
 
         if (!r)
-                (void) commit_or_fallback(pool);
+                (void) commit(pool);
 
         return r;
 }
@@ -2554,7 +2547,7 @@ static void pool_status(struct dm_target *ti, status_type_t type,
 
                 /* Commit to ensure statistics aren't out-of-date */
                 if (!(status_flags & DM_STATUS_NOFLUSH_FLAG) && !dm_suspended(ti))
-                        (void) commit_or_fallback(pool);
+                        (void) commit(pool);
 
                 r = dm_pool_get_metadata_transaction_id(pool->pmd, &transaction_id);
                 if (r) {