Btrfs: Update find free objectid function for orphan cleanup code

Orphan items use BTRFS_ORPHAN_OBJECTID (-5UUL) as key objectid. This
affects the find free objectid functions, inode objectid can easily
overflow after orphan file cleanup.

---

Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 754c738ec2e89ee28b9fcc1eab090225f2f84ec7..2ed6918f32e5de0c46388ecc907948b2ba22a2c1 100644 (file)
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -82,9 +82,10 @@ struct btrfs_ordered_sum;
 #define BTRFS_TREE_LOG_FIXUP_OBJECTID -7ULL
 
 /*
- * All files have objectids higher than this.
+ * All files have objectids in this range.
  */
 #define BTRFS_FIRST_FREE_OBJECTID 256ULL
+#define BTRFS_LAST_FREE_OBJECTID -256ULL
 #define BTRFS_FIRST_CHUNK_TREE_OBJECTID 256ULL
 
 

diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index 298346ae1481e4f1ef64515887a259bc4818e3db..cd6171c2da4296fe213a07491ff6c1f20ec0220d 100644 (file)
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -32,7 +32,8 @@ int btrfs_find_highest_inode(struct btrfs_root *root, u64 *objectid)
        path = btrfs_alloc_path();
        BUG_ON(!path);
 
-       search_key.objectid = (u64)-1;
+       search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
+       search_key.type = -1;
        search_key.offset = (u64)-1;
        ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
        if (ret < 0)
@@ -70,16 +71,17 @@ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
        u64 search_start = dirid;
 
        mutex_lock(&root->objectid_mutex);
-       if (root->last_inode_alloc) {
+       if (root->last_inode_alloc >= BTRFS_FIRST_FREE_OBJECTID &&
+           root->last_inode_alloc < BTRFS_LAST_FREE_OBJECTID) {
                *objectid = ++root->last_inode_alloc;
                mutex_unlock(&root->objectid_mutex);
                return 0;
        }
        path = btrfs_alloc_path();
        BUG_ON(!path);
-       search_start = root->last_inode_alloc;
        search_start = max(search_start, BTRFS_FIRST_FREE_OBJECTID);
        search_key.objectid = search_start;
+       search_key.type = 0;
        search_key.offset = 0;
 
        btrfs_init_path(path);
@@ -88,9 +90,6 @@ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
        if (ret < 0)
                goto error;
 
-       if (path->slots[0] > 0)
-               path->slots[0]--;
-
        while (1) {
                l = path->nodes[0];
                slot = path->slots[0];
@@ -120,13 +119,15 @@ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
                                }
                        }
                }
+               if (key.objectid >= BTRFS_LAST_FREE_OBJECTID)
+                       break;
                start_found = 1;
                last_ino = key.objectid + 1;
                path->slots[0]++;
        }
        // FIXME -ENOSPC
+       BUG_ON(1);
 found:
-       root->last_inode_alloc = *objectid;
        btrfs_release_path(root, path);
        btrfs_free_path(path);
        BUG_ON(*objectid < search_start);