On 02/05/2018 02:47 PM, Qu Wenruo wrote:
Btrfs can delay inode deletion and in that case btrfs will unlink the
victim inode from its parent dir, and insert a marker to info btrfs to
delete it later.

In that case, such victim inode will have nlinks == 0, but is still
completely valid.
Original mode won't report such problem, but lowmem mode doesn't check
the ORPHAN_ITEM key for such inode, and can report false alert like:
------
ERROR: root 257 INODE[28891726] is orphan item
------

Fix such false alert by checking orphan item for inode whose nlink is 0.

Signed-off-by: Qu Wenruo <w...@suse.com>
---
  check/mode-lowmem.c | 24 ++++++++++++++++++++++--
  1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/check/mode-lowmem.c b/check/mode-lowmem.c
index 62bcf3d2e126..b11a6d77d102 100644
--- a/check/mode-lowmem.c
+++ b/check/mode-lowmem.c
@@ -1861,6 +1861,24 @@ out:
        return ret;
  }
+static bool has_orphan_item(struct btrfs_root *root, u64 ino)
+{
+       struct btrfs_path path;
+       struct btrfs_key key;
+       int ret;
+
+       btrfs_init_path(&path);
+       key.objectid = BTRFS_ORPHAN_OBJECTID;
+       key.type = BTRFS_ORPHAN_ITEM_KEY;
+       key.offset = ino;
+
+       ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
+       btrfs_release_path(&path);
+       if (ret == 0)
+               return true;
+       return false;
+}
+

Suggestion:
Maybe "is_orphan_item" is a better name?
Anyway,

Reviewed-by: Su Yue <suy.f...@cn.fujitsu.com>

  /*
   * Check INODE_ITEM and related ITEMs (the same inode number)
   * 1. check link count
@@ -1890,6 +1908,7 @@ static int check_inode_item(struct btrfs_root *root, 
struct btrfs_path *path,
        u64 extent_size = 0;
        unsigned int dir;
        unsigned int nodatasum;
+       bool is_orphan = false;
        int slot;
        int ret;
        int err = 0;
@@ -2040,10 +2059,11 @@ out:
                                      root->objectid, inode_id, nlink, refs);
                        }
                } else if (!nlink) {
-                       if (repair)
+                       is_orphan = has_orphan_item(root, inode_id);
+                       if (!is_orphan && repair)
                                ret = repair_inode_orphan_item_lowmem(root,
                                                              path, inode_id);
-                       if (!repair || ret) {
+                       if (!is_orphan && (!repair || ret)) {
                                err |= ORPHAN_ITEM;
                                error("root %llu INODE[%llu] is orphan item",
                                      root->objectid, inode_id);



--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to