1 files changed, 42 insertions, 29 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 7527523c2d2d..376656f65b33 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1323,8 +1323,25 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
                          struct btrfs_root *root)
 {
-        finish_current_insert(trans, root->fs_info->extent_root, 1);
-        del_pending_extents(trans, root->fs_info->extent_root, 1);
+        u64 start;
+        u64 end;
+        int ret;
+
+        while(1) {
+                finish_current_insert(trans, root->fs_info->extent_root, 1);
+                del_pending_extents(trans, root->fs_info->extent_root, 1);
+
+                /* is there more work to do? */
+                ret = find_first_extent_bit(&root->fs_info->pending_del,
+                                            0, &start, &end, EXTENT_WRITEBACK);
+                if (!ret)
+                        continue;
+                ret = find_first_extent_bit(&root->fs_info->extent_ins,
+                                            0, &start, &end, EXTENT_WRITEBACK);
+                if (!ret)
+                        continue;
+                break;
+        }
         return 0;
 }
 
@@ -2211,13 +2228,12 @@ static int finish_current_insert(struct btrfs_trans_handle *trans,
         u64 end;
         u64 priv;
         u64 search = 0;
-        u64 skipped = 0;
         struct btrfs_fs_info *info = extent_root->fs_info;
         struct btrfs_path *path;
         struct pending_extent_op *extent_op, *tmp;
         struct list_head insert_list, update_list;
         int ret;
-        int num_inserts = 0, max_inserts;
+        int num_inserts = 0, max_inserts, restart = 0;
 
         path = btrfs_alloc_path();
         INIT_LIST_HEAD(&insert_list);
@@ -2233,19 +2249,19 @@ again:
                 ret = find_first_extent_bit(&info->extent_ins, search, &start,
                                             &end, EXTENT_WRITEBACK);
                 if (ret) {
-                        if (skipped && all && !num_inserts &&
+                        if (restart && !num_inserts &&
                             list_empty(&update_list)) {
-                                skipped = 0;
+                                restart = 0;
                                 search = 0;
                                 continue;
                         }
-                        mutex_unlock(&info->extent_ins_mutex);
                         break;
                 }
 
                 ret = try_lock_extent(&info->extent_ins, start, end, GFP_NOFS);
                 if (!ret) {
-                        skipped = 1;
+                        if (all)
+                                restart = 1;
                         search = end + 1;
                         if (need_resched()) {
                                 mutex_unlock(&info->extent_ins_mutex);
@@ -2264,7 +2280,7 @@ again:
                         list_add_tail(&extent_op->list, &insert_list);
                         search = end + 1;
                         if (num_inserts == max_inserts) {
-                                mutex_unlock(&info->extent_ins_mutex);
+                                restart = 1;
                                 break;
                         }
                 } else if (extent_op->type == PENDING_BACKREF_UPDATE) {
@@ -2280,7 +2296,6 @@ again:
          * somebody marked this thing for deletion then just unlock it and be
          * done, the free_extents will handle it
          */
-        mutex_lock(&info->extent_ins_mutex);
         list_for_each_entry_safe(extent_op, tmp, &update_list, list) {
                 clear_extent_bits(&info->extent_ins, extent_op->bytenr,
                                   extent_op->bytenr + extent_op->num_bytes - 1,
@@ -2302,6 +2317,10 @@ again:
         if (!list_empty(&update_list)) {
                 ret = update_backrefs(trans, extent_root, path, &update_list);
                 BUG_ON(ret);
+
+                /* we may have COW'ed new blocks, so lets start over */
+                if (all)
+                        restart = 1;
         }
 
         /*
@@ -2309,9 +2328,9 @@ again:
          * need to make sure everything is cleaned then reset everything and
          * go back to the beginning
          */
-        if (!num_inserts && all && skipped) {
+        if (!num_inserts && restart) {
                 search = 0;
-                skipped = 0;
+                restart = 0;
                 INIT_LIST_HEAD(&update_list);
                 INIT_LIST_HEAD(&insert_list);
                 goto again;
@@ -2368,27 +2387,19 @@ again:
         BUG_ON(ret);
 
         /*
-         * if we broke out of the loop in order to insert stuff because we hit
-         * the maximum number of inserts at a time we can handle, then loop
-         * back and pick up where we left off
+         * if restart is set for whatever reason we need to go back and start
+         * searching through the pending list again.
+         *
+         * We just inserted some extents, which could have resulted in new
+         * blocks being allocated, which would result in new blocks needing
+         * updates, so if all is set we _must_ restart to get the updated
+         * blocks.
          */
-        if (num_inserts == max_inserts) {
-                INIT_LIST_HEAD(&insert_list);
-                INIT_LIST_HEAD(&update_list);
-                num_inserts = 0;
-                goto again;
-        }
-
-        /*
-         * again, if we need to make absolutely sure there are no more pending
-         * extent operations left and we know that we skipped some, go back to
-         * the beginning and do it all again
-         */
-        if (all && skipped) {
+        if (restart || all) {
                 INIT_LIST_HEAD(&insert_list);
                 INIT_LIST_HEAD(&update_list);
                 search = 0;
-                skipped = 0;
+                restart = 0;
                 num_inserts = 0;
                 goto again;
         }
@@ -2709,6 +2720,8 @@ again:
                 goto again;
         }
 
+        if (!err)
+                finish_current_insert(trans, extent_root, 0);
         return err;
 }