Merge tag 'dm-4.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - fix a 4.6-rc1 bio-based DM 'struct dm_target_io' leak in an error
   path

 - stable@ fix for DM cache metadata's READ_LOCK macros that were
   incorrectly returning error if the block manager was in read-only
   mode; also cleanup multi-statement macros to use do {} while(0)

* tag 'dm-4.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros
  dm: fix dm_target_io leak if clone_bio() returns an error

2 files changed, 43 insertions, 25 deletions

diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c
index 27f2ef300f8b..65ce6985f87a 100644
--- a/drivers/md/dm-cache-metadata.c
+++ b/drivers/md/dm-cache-metadata.c
@@ -867,39 +867,55 @@ static int blocks_are_unmapped_or_clean(struct dm_cache_metadata *cmd,
         return 0;
 }
 
-#define WRITE_LOCK(cmd) \
-        down_write(&cmd->root_lock); \
-        if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \
-                up_write(&cmd->root_lock); \
-                return -EINVAL; \
+static bool cmd_write_lock(struct dm_cache_metadata *cmd)
+{
+        down_write(&cmd->root_lock);
+        if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) {
+                up_write(&cmd->root_lock);
+                return false;
         }
+        return true;
+}
 
-#define WRITE_LOCK_VOID(cmd) \
-        down_write(&cmd->root_lock); \
-        if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \
-                up_write(&cmd->root_lock); \
-                return; \
-        }
+#define WRITE_LOCK(cmd)                         \
+        do {                                    \
+                if (!cmd_write_lock((cmd)))     \
+                        return -EINVAL;         \
+        } while(0)
+
+#define WRITE_LOCK_VOID(cmd)                    \
+        do {                                    \
+                if (!cmd_write_lock((cmd)))     \
+                        return;                 \
+        } while(0)
 
 #define WRITE_UNLOCK(cmd) \
-        up_write(&cmd->root_lock)
+        up_write(&(cmd)->root_lock)
 
-#define READ_LOCK(cmd) \
-        down_read(&cmd->root_lock); \
-        if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \
-                up_read(&cmd->root_lock); \
-                return -EINVAL; \
+static bool cmd_read_lock(struct dm_cache_metadata *cmd)
+{
+        down_write(&cmd->root_lock);
+        if (cmd->fail_io) {
+                up_write(&cmd->root_lock);
+                return false;
         }
+        return true;
+}
 
-#define READ_LOCK_VOID(cmd)     \
-        down_read(&cmd->root_lock); \
-        if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \
-                up_read(&cmd->root_lock); \
-                return; \
-        }
+#define READ_LOCK(cmd)                          \
+        do {                                    \
+                if (!cmd_read_lock((cmd)))      \
+                        return -EINVAL;         \
+        } while(0)
+
+#define READ_LOCK_VOID(cmd)                     \
+        do {                                    \
+                if (!cmd_read_lock((cmd)))      \
+                        return;                 \
+        } while(0)
 
 #define READ_UNLOCK(cmd) \
-        up_read(&cmd->root_lock)
+        up_read(&(cmd)->root_lock)
 
 int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size)
 {
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index be4905769a45..3d3ac13287a4 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1662,8 +1662,10 @@ static int __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti,
                 tio = alloc_tio(ci, ti, target_bio_nr);
                 tio->len_ptr = len;
                 r = clone_bio(tio, bio, sector, *len);
-                if (r < 0)
+                if (r < 0) {
+                        free_tio(ci->md, tio);
                         break;
+                }
                 __map_bio(tio);
         }