1 files changed, 23 insertions, 15 deletions

diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index 1b4e1756b169..b680da5d7b93 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -424,7 +424,6 @@ static void free_migration(struct dm_cache_migration *mg)
                 wake_up(&cache->migration_wait);
 
         mempool_free(mg, cache->migration_pool);
-        wake_worker(cache);
 }
 
 static int prealloc_data_structs(struct cache *cache, struct prealloc *p)
@@ -1947,6 +1946,7 @@ static int commit_if_needed(struct cache *cache)
 
 static void process_deferred_bios(struct cache *cache)
 {
+        bool prealloc_used = false;
         unsigned long flags;
         struct bio_list bios;
         struct bio *bio;
@@ -1981,13 +1981,16 @@ static void process_deferred_bios(struct cache *cache)
                         process_discard_bio(cache, &structs, bio);
                 else
                         process_bio(cache, &structs, bio);
+                prealloc_used = true;
         }
 
-        prealloc_free_structs(cache, &structs);
+        if (prealloc_used)
+                prealloc_free_structs(cache, &structs);
 }
 
 static void process_deferred_cells(struct cache *cache)
 {
+        bool prealloc_used = false;
         unsigned long flags;
         struct dm_bio_prison_cell *cell, *tmp;
         struct list_head cells;
@@ -2015,9 +2018,11 @@ static void process_deferred_cells(struct cache *cache)
                 }
 
                 process_cell(cache, &structs, cell);
+                prealloc_used = true;
         }
 
-        prealloc_free_structs(cache, &structs);
+        if (prealloc_used)
+                prealloc_free_structs(cache, &structs);
 }
 
 static void process_deferred_flush_bios(struct cache *cache, bool submit_bios)
@@ -2062,7 +2067,7 @@ static void process_deferred_writethrough_bios(struct cache *cache)
 
 static void writeback_some_dirty_blocks(struct cache *cache)
 {
-        int r = 0;
+        bool prealloc_used = false;
         dm_oblock_t oblock;
         dm_cblock_t cblock;
         struct prealloc structs;
@@ -2072,23 +2077,21 @@ static void writeback_some_dirty_blocks(struct cache *cache)
         memset(&structs, 0, sizeof(structs));
 
         while (spare_migration_bandwidth(cache)) {
-                if (prealloc_data_structs(cache, &structs))
-                        break;
+                if (policy_writeback_work(cache->policy, &oblock, &cblock, busy))
+                        break; /* no work to do */
 
-                r = policy_writeback_work(cache->policy, &oblock, &cblock, busy);
-                if (r)
-                        break;
-
-                r = get_cell(cache, oblock, &structs, &old_ocell);
-                if (r) {
+                if (prealloc_data_structs(cache, &structs) ||
+                    get_cell(cache, oblock, &structs, &old_ocell)) {
                         policy_set_dirty(cache->policy, oblock);
                         break;
                 }
 
                 writeback(cache, &structs, oblock, cblock, old_ocell);
+                prealloc_used = true;
         }
 
-        prealloc_free_structs(cache, &structs);
+        if (prealloc_used)
+                prealloc_free_structs(cache, &structs);
 }
 
 /*----------------------------------------------------------------
@@ -3496,7 +3499,7 @@ static void cache_resume(struct dm_target *ti)
  * <#demotions> <#promotions> <#dirty>
  * <#features> <features>*
  * <#core args> <core args>
- * <policy name> <#policy args> <policy args>* <cache metadata mode>
+ * <policy name> <#policy args> <policy args>* <cache metadata mode> <needs_check>
  */
 static void cache_status(struct dm_target *ti, status_type_t type,
                          unsigned status_flags, char *result, unsigned maxlen)
@@ -3582,6 +3585,11 @@ static void cache_status(struct dm_target *ti, status_type_t type,
                 else
                         DMEMIT("rw ");
 
+                if (dm_cache_metadata_needs_check(cache->cmd))
+                        DMEMIT("needs_check ");
+                else
+                        DMEMIT("- ");
+
                 break;
 
         case STATUSTYPE_TABLE:
@@ -3820,7 +3828,7 @@ static void cache_io_hints(struct dm_target *ti, struct queue_limits *limits)
 
 static struct target_type cache_target = {
         .name = "cache",
-        .version = {1, 7, 0},
+        .version = {1, 8, 0},
         .module = THIS_MODULE,
         .ctr = cache_ctr,
         .dtr = cache_dtr,