xfs: add fsgeom flag for v5 superblock support.

Currently userspace has no way of determining that a filesystem is
CRC enabled. Add a flag to the XFS_IOC_FSGEOMETRY ioctl output to
indicate that the filesystem has v5 superblock support enabled.
This will allow xfs_info to correctly report the state of the
filesystem.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 74137fff067961c9aca1e14d073805c3de8549bd)

2 files changed, 4 insertions, 1 deletions

diff --git a/fs/xfs/xfs_fs.h b/fs/xfs/xfs_fs.h
index 6dda3f949b04..d04695545397 100644
--- a/fs/xfs/xfs_fs.h
+++ b/fs/xfs/xfs_fs.h
@@ -236,6 +236,7 @@ typedef struct xfs_fsop_resblks {
 #define XFS_FSOP_GEOM_FLAGS_PROJID32    0x0800  /* 32-bit project IDs   */
 #define XFS_FSOP_GEOM_FLAGS_DIRV2CI     0x1000  /* ASCII only CI names  */
 #define XFS_FSOP_GEOM_FLAGS_LAZYSB      0x4000  /* lazy superblock counters */
+#define XFS_FSOP_GEOM_FLAGS_V5SB        0x8000  /* version 5 superblock */
 
 
 /*
diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
index 87595b211da1..3c3644ea825b 100644
--- a/fs/xfs/xfs_fsops.c
+++ b/fs/xfs/xfs_fsops.c
@@ -99,7 +99,9 @@ xfs_fs_geometry(
                         (xfs_sb_version_hasattr2(&mp->m_sb) ?
                                 XFS_FSOP_GEOM_FLAGS_ATTR2 : 0) |
                         (xfs_sb_version_hasprojid32bit(&mp->m_sb) ?
-                                XFS_FSOP_GEOM_FLAGS_PROJID32 : 0);
+                                XFS_FSOP_GEOM_FLAGS_PROJID32 : 0) |
+                        (xfs_sb_version_hascrc(&mp->m_sb) ?
+                                XFS_FSOP_GEOM_FLAGS_V5SB : 0);
                 geo->logsectsize = xfs_sb_version_hassector(&mp->m_sb) ?
                                 mp->m_sb.sb_logsectsize : BBSIZE;
                 geo->rtsectsize = mp->m_sb.sb_blocksize;