Merge branch 'keys-devel' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells...

[firefly-linux-kernel-4.4.55.git] / drivers / md / dm-thin.c

diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 44ee489f4a6e4ca19d9010956170e092860c94bd..ee29037ffc2e74633050b708718ccbe963bf20d1 100644 (file)
--- 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;
@@ -1407,6 +1400,7 @@ static void set_pool_mode(struct pool *pool, enum pool_mode mode)
        case PM_FAIL:
                DMERR("%s: switching pool to failure mode",
                      dm_device_name(pool->pool_md));
+               dm_pool_metadata_read_only(pool->pmd);
                pool->process_bio = process_bio_fail;
                pool->process_discard = process_bio_fail;
                pool->process_prepared_mapping = process_prepared_mapping_fail;
@@ -1431,6 +1425,7 @@ static void set_pool_mode(struct pool *pool, enum pool_mode mode)
                break;
 
        case PM_WRITE:
+               dm_pool_metadata_read_write(pool->pmd);
                pool->process_bio = process_bio;
                pool->process_discard = process_discard;
                pool->process_prepared_mapping = process_prepared_mapping;
@@ -1647,12 +1642,19 @@ static int bind_control_target(struct pool *pool, struct dm_target *ti)
        struct pool_c *pt = ti->private;
 
        /*
-        * We want to make sure that degraded pools are never upgraded.
+        * We want to make sure that a pool in PM_FAIL mode is never upgraded.
         */
        enum pool_mode old_mode = pool->pf.mode;
        enum pool_mode new_mode = pt->adjusted_pf.mode;
 
-       if (old_mode > new_mode)
+       /*
+        * If we were in PM_FAIL mode, rollback of metadata failed.  We're
+        * not going to recover without a thin_repair.  So we never let the
+        * pool move out of the old mode.  On the other hand a PM_READ_ONLY
+        * may have been due to a lack of metadata or data space, and may
+        * now work (ie. if the underlying devices have been resized).
+        */
+       if (old_mode == PM_FAIL)
                new_mode = old_mode;
 
        pool->ti = ti;
@@ -2276,7 +2278,7 @@ 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 +2305,7 @@ 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 +2439,7 @@ 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 +2501,7 @@ 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 +2556,7 @@ 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) {