Btrfs: drop dir i_size when adding new names on replay

So if we have dir_index items in the log that means we also have the inode item
as well, which means that the inode's i_size is correct.  However when we
process dir_index'es we call btrfs_add_link() which will increase the
directory's i_size for the new entry.  To fix this we need to just set the dir
items i_size to 0, and then as we find dir_index items we adjust the i_size.
btrfs_add_link() will do it for new entries, and if the entry already exists we
can just add the name_len to the i_size ourselves.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index c91309dea8da..79f057c0619a 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -394,6 +394,7 @@ static noinline int overwrite_item(struct btrfs_trans_handle *trans,
                 if (inode_item) {
                         struct btrfs_inode_item *item;
                         u64 nbytes;
+                        u32 mode;
 
                         item = btrfs_item_ptr(path->nodes[0], path->slots[0],
                                               struct btrfs_inode_item);
@@ -401,9 +402,19 @@ static noinline int overwrite_item(struct btrfs_trans_handle *trans,
                         item = btrfs_item_ptr(eb, slot,
                                               struct btrfs_inode_item);
                         btrfs_set_inode_nbytes(eb, item, nbytes);
+
+                        /*
+                         * If this is a directory we need to reset the i_size to
+                         * 0 so that we can set it up properly when replaying
+                         * the rest of the items in this log.
+                         */
+                        mode = btrfs_inode_mode(eb, item);
+                        if (S_ISDIR(mode))
+                                btrfs_set_inode_size(eb, item, 0);
                 }
         } else if (inode_item) {
                 struct btrfs_inode_item *item;
+                u32 mode;
 
                 /*
                  * New inode, set nbytes to 0 so that the nbytes comes out
@@ -411,6 +422,15 @@ static noinline int overwrite_item(struct btrfs_trans_handle *trans,
                  */
                 item = btrfs_item_ptr(eb, slot, struct btrfs_inode_item);
                 btrfs_set_inode_nbytes(eb, item, 0);
+
+                /*
+                 * If this is a directory we need to reset the i_size to 0 so
+                 * that we can set it up properly when replaying the rest of
+                 * the items in this log.
+                 */
+                mode = btrfs_inode_mode(eb, item);
+                if (S_ISDIR(mode))
+                        btrfs_set_inode_size(eb, item, 0);
         }
 insert:
         btrfs_release_path(path);
@@ -1497,6 +1517,7 @@ static noinline int insert_one_name(struct btrfs_trans_handle *trans,
                 iput(inode);
                 return -EIO;
         }
+
         ret = btrfs_add_link(trans, dir, inode, name, name_len, 1, index);
 
         /* FIXME, put inode into FIXUP list */
@@ -1535,6 +1556,7 @@ static noinline int replay_one_name(struct btrfs_trans_handle *trans,
         u8 log_type;
         int exists;
         int ret = 0;
+        bool update_size = (key->type == BTRFS_DIR_INDEX_KEY);
 
         dir = read_one_inode(root, key->objectid);
         if (!dir)
@@ -1605,6 +1627,10 @@ static noinline int replay_one_name(struct btrfs_trans_handle *trans,
                 goto insert;
 out:
         btrfs_release_path(path);
+        if (!ret && update_size) {
+                btrfs_i_size_write(dir, dir->i_size + name_len * 2);
+                ret = btrfs_update_inode(trans, root, dir);
+        }
         kfree(name);
         iput(dir);
         return ret;
@@ -1615,6 +1641,7 @@ insert:
                               name, name_len, log_type, &log_key);
         if (ret && ret != -ENOENT)
                 goto out;
+        update_size = false;
         ret = 0;
         goto out;
 }