xfs: fix the wrong new_size/rnew_size at xfs_iext_realloc_direct()

At xfs_iext_realloc_direct(), the new_size is changed by adding
if_bytes if originally the extent records are stored at the inline
extent buffer, and we have to switch from it to a direct extent
list for those new allocated extents, this is wrong.

This patch fix above problem and revise the new_size comments at
xfs_iext_realloc_direct() to make it more readable.  Also, fix the
comments while switching from the inline extent buffer to a direct
extent list to reflect this change.

Ported from kernel commit 17ec81c1.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Rich Johnston <rjohnston@sgi.com>

diff --git a/libxfs/xfs_inode_fork.c b/libxfs/xfs_inode_fork.c
index 190690c0cc80ee7df3edae462e3bee8400b47818..dfa86aece13872fe4c5ea2c1d5966aa65e19d896 100644 (file)
--- a/libxfs/xfs_inode_fork.c
+++ b/libxfs/xfs_inode_fork.c
@@ -1330,7 +1330,7 @@ xfs_iext_remove_indirect(
 void
 xfs_iext_realloc_direct(
        xfs_ifork_t     *ifp,           /* inode fork pointer */
-       int             new_size)       /* new size of extents */
+       int             new_size)       /* new size of extents after adding */
 {
        int             rnew_size;      /* real new size of extents */
 
@@ -1368,13 +1368,8 @@ xfs_iext_realloc_direct(
                                rnew_size - ifp->if_real_bytes);
                }
        }
-       /*
-        * Switch from the inline extent buffer to a direct
-        * extent list. Be sure to include the inline extent
-        * bytes in new_size.
-        */
+       /* Switch from the inline extent buffer to a direct extent list */
        else {
-               new_size += ifp->if_bytes;
                if (!is_power_of_2(new_size)) {
                        rnew_size = roundup_pow_of_two(new_size);
                }