Make inode64 a remountable option

Actually, there is no reason about why a user must umount and mount a
XFS filesystem to enable 'inode64' option. So, this patch makes this a
remountable option.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

1 files changed, 29 insertions, 1 deletions

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 19e2380fb867..c416a01fcb14 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -120,12 +120,13 @@ mempool_t *xfs_ioend_pool;
  * in the future, too.
  */
 enum {
-        Opt_barrier, Opt_nobarrier, Opt_err
+        Opt_barrier, Opt_nobarrier, Opt_inode64, Opt_err
 };
 
 static const match_table_t tokens = {
         {Opt_barrier, "barrier"},
         {Opt_nobarrier, "nobarrier"},
+        {Opt_inode64, "inode64"},
         {Opt_err, NULL}
 };
 
@@ -1031,6 +1032,30 @@ xfs_restore_resvblks(struct xfs_mount *mp)
         xfs_reserve_blocks(mp, &resblks, NULL);
 }
 
+STATIC void
+xfs_set_inode64(struct xfs_mount *mp)
+{
+        int i = 0;
+
+        for (i = 0; i < mp->m_sb.sb_agcount; i++) {
+                struct xfs_perag        *pag;
+
+                pag = xfs_perag_get(mp, i);
+                pag->pagi_inodeok = 1;
+                pag->pagf_metadata = 0;
+                xfs_perag_put(pag);
+        }
+
+        /* There is no need for lock protection on m_flags,
+         * the rw_semaphore of the VFS superblock is locked
+         * during mount/umount/remount operations, so this is
+         * enough to avoid concurency on the m_flags field
+         */
+        mp->m_flags &= ~(XFS_MOUNT_32BITINODES |
+                         XFS_MOUNT_SMALL_INUMS);
+        mp->m_maxagi = i;
+}
+
 STATIC int
 xfs_fs_remount(
         struct super_block      *sb,
@@ -1056,6 +1081,9 @@ xfs_fs_remount(
                 case Opt_nobarrier:
                         mp->m_flags &= ~XFS_MOUNT_BARRIER;
                         break;
+                case Opt_inode64:
+                        xfs_set_inode64(mp);
+                        break;
                 default:
                         /*
                          * Logically we would return an error here to prevent