Btrfs: Make truncate(2) more ENOSPC friendly

truncating and deleting regular files are unbound operations,
so it's not good to do them in a single transaction. This
patch makes btrfs_truncate and btrfs_delete_inode start a
new transaction after all items in a tree leaf are deleted.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 20 insertions, 13 deletions

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 975fdd33ac41..f2aa53d2f944 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -1561,6 +1561,20 @@ static int invalidate_extent_cache(struct btrfs_root *root,
         return 0;
 }
 
+static void put_inodes(struct list_head *list)
+{
+        struct inodevec *ivec;
+        while (!list_empty(list)) {
+                ivec = list_entry(list->next, struct inodevec, list);
+                list_del(&ivec->list);
+                while (ivec->nr > 0) {
+                        ivec->nr--;
+                        iput(ivec->inode[ivec->nr]);
+                }
+                kfree(ivec);
+        }
+}
+
 static int find_next_key(struct btrfs_path *path, int level,
                          struct btrfs_key *key)
 
@@ -1723,6 +1737,11 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
 
                 btrfs_btree_balance_dirty(root, nr);
 
+                /*
+                 * put inodes outside transaction, otherwise we may deadlock.
+                 */
+                put_inodes(&inode_list);
+
                 if (replaced && rc->stage == UPDATE_DATA_PTRS)
                         invalidate_extent_cache(root, &key, &next_key);
         }
@@ -1752,19 +1771,7 @@ out:
 
         btrfs_btree_balance_dirty(root, nr);
 
-        /*
-         * put inodes while we aren't holding the tree locks
-         */
-        while (!list_empty(&inode_list)) {
-                struct inodevec *ivec;
-                ivec = list_entry(inode_list.next, struct inodevec, list);
-                list_del(&ivec->list);
-                while (ivec->nr > 0) {
-                        ivec->nr--;
-                        iput(ivec->inode[ivec->nr]);
-                }
-                kfree(ivec);
-        }
+        put_inodes(&inode_list);
 
         if (replaced && rc->stage == UPDATE_DATA_PTRS)
                 invalidate_extent_cache(root, &key, &next_key);