[PATCH] Make inode64 a remountable option

[Carlos Maiolino <cmaiolino@xxxxxxxxxx>]

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@xxxxxxxxxx>
---
 fs/xfs/xfs_super.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index bdaf4cb..4dad567 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}
 };
 
@@ -1038,11 +1039,15 @@ xfs_fs_remount(
 {
        struct xfs_mount        *mp = XFS_M(sb);
        substring_t             args[MAX_OPT_ARGS];
+       xfs_sb_t                *sbp = &(mp->m_sb);
+       xfs_perag_t             *pag;
        char                    *p;
        int                     error;
 
        while ((p = strsep(&options, ",")) != NULL) {
                int token;
+               int agcount = sbp->sb_agcount;
+               int index = 0;
 
                if (!*p)
                        continue;
@@ -1055,6 +1060,17 @@ xfs_fs_remount(
                case Opt_nobarrier:
                        mp->m_flags &= ~XFS_MOUNT_BARRIER;
                        break;
+               case Opt_inode64:
+
+                       for (index = 0; index < agcount; index++) {
+                               pag = xfs_perag_get(mp, index);
+                               pag->pagi_inodeok = 1;
+                               xfs_perag_put(pag);
+                       }
+                       mp->m_flags &= ~XFS_MOUNT_32BITINODES;
+                       mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS;
+                       mp->m_maxagi = index;
+                       break;
                default:
                        /*
                         * Logically we would return an error here to prevent
-- 
1.7.11.2