ext4: don't calculate total xattr header size unless needed

The function ext4_expand_extra_isize_ea() doesn't need the size of all
of the extended attribute headers.  So if we don't calculate it when
it is unneeded, it we can skip some undeeded memory references, and as
a bonus, we eliminate some kvetching by static code analysis tools.

Addresses-Coverity-Id: #741291

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 4 insertions, 4 deletions

diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index e175e94116ac..185066f475f1 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -567,12 +567,13 @@ static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last,
                                     size_t *min_offs, void *base, int *total)
 {
         for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
-                *total += EXT4_XATTR_LEN(last->e_name_len);
                 if (!last->e_value_block && last->e_value_size) {
                         size_t offs = le16_to_cpu(last->e_value_offs);
                         if (offs < *min_offs)
                                 *min_offs = offs;
                 }
+                if (total)
+                        *total += EXT4_XATTR_LEN(last->e_name_len);
         }
         return (*min_offs - ((void *)last - base) - sizeof(__u32));
 }
@@ -1228,7 +1229,7 @@ int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
         struct ext4_xattr_block_find *bs = NULL;
         char *buffer = NULL, *b_entry_name = NULL;
         size_t min_offs, free;
-        int total_ino, total_blk;
+        int total_ino;
         void *base, *start, *end;
         int extra_isize = 0, 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);
@@ -1286,8 +1287,7 @@ retry:
                 first = BFIRST(bh);
                 end = bh->b_data + bh->b_size;
                 min_offs = end - base;
-                free = ext4_xattr_free_space(first, &min_offs, base,
-                                             &total_blk);
+                free = ext4_xattr_free_space(first, &min_offs, base, NULL);
                 if (free < new_extra_isize) {
                         if (!tried_min_extra_isize && s_min_extra_isize) {
                                 tried_min_extra_isize++;