ext4: fix forgetten xattr lock protection in ext4_expand_extra_isize

We should avoid the contention between the i_extra_isize update and
the inline data insertion, so move the xattr trylock in front of
i_extra_isize update.

Signed-off-by: Miao Xie <miaoxie@huawei.com>
Reviewed-by: Wang Shilong <wshilong@ddn.com>

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 56bca45..5dabbf2 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5713,10 +5713,15 @@ static int ext4_expand_extra_isize(struct inode *inode,
 {
        struct ext4_inode *raw_inode;
        struct ext4_xattr_ibody_header *header;
+       int no_expand;
+       int error;
 
        if (EXT4_I(inode)->i_extra_isize >= new_extra_isize)
                return 0;
 
+       if (ext4_write_trylock_xattr(inode, &no_expand) == 0)
+               return 0;
+
        raw_inode = ext4_raw_inode(&iloc);
 
        header = IHDR(inode, raw_inode);
@@ -5728,12 +5733,21 @@ static int ext4_expand_extra_isize(struct inode *inode,
                       EXT4_I(inode)->i_extra_isize, 0,
                       new_extra_isize - EXT4_I(inode)->i_extra_isize);
                EXT4_I(inode)->i_extra_isize = new_extra_isize;
+               ext4_write_unlock_xattr(inode, &no_expand);
                return 0;
        }
 
        /* try to expand with EAs present */
-       return ext4_expand_extra_isize_ea(inode, new_extra_isize,
-                                         raw_inode, handle);
+       error = ext4_expand_extra_isize_ea(inode, new_extra_isize,
+                                          raw_inode, handle);
+       if (error) {
+               /*
+                * Inode size expansion failed; don't try again
+                */
+               no_expand = 1;
+       }
+       ext4_write_unlock_xattr(inode, &no_expand);
+       return error;
 }
 
 /*

diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index 5fa912e..862ba38 100644 (file)
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -2645,10 +2645,6 @@ int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
        int error = 0, tried_min_extra_isize = 0;
        int s_min_extra_isize = le16_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize);
        int isize_diff; /* How much do we need to grow i_extra_isize */
-       int no_expand;
-
-       if (ext4_write_trylock_xattr(inode, &no_expand) == 0)
-               return 0;
 
 retry:
        isize_diff = new_extra_isize - EXT4_I(inode)->i_extra_isize;
@@ -2731,16 +2727,10 @@ shift:
        EXT4_I(inode)->i_extra_isize = new_extra_isize;
        brelse(bh);
 out:
-       ext4_write_unlock_xattr(inode, &no_expand);
        return 0;
 
 cleanup:
        brelse(bh);
-       /*
-        * Inode size expansion failed; don't try again
-        */
-       no_expand = 1;
-       ext4_write_unlock_xattr(inode, &no_expand);
        return error;
 }