btrfs: tree-checker: Refactor prev_key check for ino into a function

Refactor the check for prev_key->objectid of the following key types
into one function, check_prev_ino():

- EXTENT_DATA
- INODE_REF
- DIR_INDEX
- DIR_ITEM
- XATTR_ITEM

Also add the check of prev_key for INODE_REF.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
index fa4848a..8b6d4cc 100644 (file)
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -125,6 +125,74 @@ static u64 file_extent_end(struct extent_buffer *leaf,
        return end;
 }
 
+/*
+ * Customized report for dir_item, the only new important information is
+ * key->objectid, which represents inode number
+ */
+__printf(3, 4)
+__cold
+static void dir_item_err(const struct extent_buffer *eb, int slot,
+                        const char *fmt, ...)
+{
+       const struct btrfs_fs_info *fs_info = eb->fs_info;
+       struct btrfs_key key;
+       struct va_format vaf;
+       va_list args;
+
+       btrfs_item_key_to_cpu(eb, &key, slot);
+       va_start(args, fmt);
+
+       vaf.fmt = fmt;
+       vaf.va = &args;
+
+       btrfs_crit(fs_info,
+               "corrupt %s: root=%llu block=%llu slot=%d ino=%llu, %pV",
+               btrfs_header_level(eb) == 0 ? "leaf" : "node",
+               btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
+               key.objectid, &vaf);
+       va_end(args);
+}
+
+/*
+ * This functions checks prev_key->objectid, to ensure current key and prev_key
+ * share the same objectid as inode number.
+ *
+ * This is to detect missing INODE_ITEM in subvolume trees.
+ *
+ * Return true if everything is OK or we don't need to check.
+ * Return false if anything is wrong.
+ */
+static bool check_prev_ino(struct extent_buffer *leaf,
+                          struct btrfs_key *key, int slot,
+                          struct btrfs_key *prev_key)
+{
+       /* No prev key, skip check */
+       if (slot == 0)
+               return true;
+
+       /* Only these key->types needs to be checked */
+       ASSERT(key->type == BTRFS_XATTR_ITEM_KEY ||
+              key->type == BTRFS_INODE_REF_KEY ||
+              key->type == BTRFS_DIR_INDEX_KEY ||
+              key->type == BTRFS_DIR_ITEM_KEY ||
+              key->type == BTRFS_EXTENT_DATA_KEY);
+
+       /*
+        * Only subvolume trees along with their reloc trees need this check.
+        * Things like log tree doesn't follow this ino requirement.
+        */
+       if (!is_fstree(btrfs_header_owner(leaf)))
+               return true;
+
+       if (key->objectid == prev_key->objectid)
+               return true;
+
+       /* Error found */
+       dir_item_err(leaf, slot,
+               "invalid previous key objectid, have %llu expect %llu",
+               prev_key->objectid, key->objectid);
+       return false;
+}
 static int check_extent_data_item(struct extent_buffer *leaf,
                                  struct btrfs_key *key, int slot,
                                  struct btrfs_key *prev_key)
@@ -148,13 +216,8 @@ static int check_extent_data_item(struct extent_buffer *leaf,
         * But if objectids mismatch, it means we have a missing
         * INODE_ITEM.
         */
-       if (slot > 0 && is_fstree(btrfs_header_owner(leaf)) &&
-           prev_key->objectid != key->objectid) {
-               file_extent_err(leaf, slot,
-               "invalid previous key objectid, have %llu expect %llu",
-                               prev_key->objectid, key->objectid);
+       if (!check_prev_ino(leaf, key, slot, prev_key))
                return -EUCLEAN;
-       }
 
        fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
 
@@ -285,34 +348,6 @@ static int check_csum_item(struct extent_buffer *leaf, struct btrfs_key *key,
        return 0;
 }
 
-/*
- * Customized reported for dir_item, only important new info is key->objectid,
- * which represents inode number
- */
-__printf(3, 4)
-__cold
-static void dir_item_err(const struct extent_buffer *eb, int slot,
-                        const char *fmt, ...)
-{
-       const struct btrfs_fs_info *fs_info = eb->fs_info;
-       struct btrfs_key key;
-       struct va_format vaf;
-       va_list args;
-
-       btrfs_item_key_to_cpu(eb, &key, slot);
-       va_start(args, fmt);
-
-       vaf.fmt = fmt;
-       vaf.va = &args;
-
-       btrfs_crit(fs_info,
-       "corrupt %s: root=%llu block=%llu slot=%d ino=%llu, %pV",
-               btrfs_header_level(eb) == 0 ? "leaf" : "node",
-               btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
-               key.objectid, &vaf);
-       va_end(args);
-}
-
 static int check_dir_item(struct extent_buffer *leaf,
                          struct btrfs_key *key, struct btrfs_key *prev_key,
                          int slot)
@@ -322,14 +357,8 @@ static int check_dir_item(struct extent_buffer *leaf,
        u32 item_size = btrfs_item_size_nr(leaf, slot);
        u32 cur = 0;
 
-       /* Same check as in check_extent_data_item() */
-       if (slot > 0 && is_fstree(btrfs_header_owner(leaf)) &&
-           prev_key->objectid != key->objectid) {
-               dir_item_err(leaf, slot,
-               "invalid previous key objectid, have %llu expect %llu",
-                            prev_key->objectid, key->objectid);
+       if (!check_prev_ino(leaf, key, slot, prev_key))
                return -EUCLEAN;
-       }
        di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
        while (cur < item_size) {
                u32 name_len;
@@ -1258,6 +1287,8 @@ static int check_inode_ref(struct extent_buffer *leaf,
        unsigned long ptr;
        unsigned long end;
 
+       if (!check_prev_ino(leaf, key, slot, prev_key))
+               return -EUCLEAN;
        /* namelen can't be 0, so item_size == sizeof() is also invalid */
        if (btrfs_item_size_nr(leaf, slot) <= sizeof(*iref)) {
                inode_ref_err(fs_info, leaf, slot,