[PATCH v6 07/12] xfs: add xfs_remount_ro() helper

Ian Kent
2019-10-16T00:41:30Z

Factor the remount read only code into a helper to simplify the
subsequent change from the super block method .remount_fs to the
mount-api fs_context_operations method .reconfigure.

Signed-off-by: Ian Kent <raven@themaw.net>
Reviewed-by: Brian Foster <bfoster@redhat.com>
---
fs/xfs/xfs_super.c | 73 +++++++++++++++++++++++++++++++---------------------
1 file changed, 43 insertions(+), 30 deletions(-)

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index cdc19c2af50f..1f706cbf9624 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1275,6 +1275,47 @@ xfs_remount_rw(
return 0;
}

+static int
+xfs_remount_ro(
+ struct xfs_mount *mp)
+{
+ int error;
+
+ /*
+ * Cancel background eofb scanning so it cannot race with the
+ * final log force+buftarg wait and deadlock the remount.
+ */
+ xfs_stop_block_reaping(mp);
+
+ /* Get rid of any leftover CoW reservations... */
+ error = xfs_icache_free_cowblocks(mp, NULL);
+ if (error) {
+ xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
+ return error;
+ }
+
+ /* Free the per-AG metadata reservation pool. */
+ error = xfs_fs_unreserve_ag_blocks(mp);
+ if (error) {
+ xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
+ return error;
+ }
+
+ /*
+ * Before we sync the metadata, we need to free up the reserve
+ * block pool so that the used block count in the superblock on
+ * disk is correct at the end of the remount. Stash the current
+ * reserve pool size so that if we get remounted rw, we can
+ * return it to the same size.
+ */
+ xfs_save_resvblks(mp);
+
+ xfs_quiesce_attr(mp);
+ mp->m_flags |= XFS_MOUNT_RDONLY;
+
+ return 0;
+}
+
STATIC int
xfs_fs_remount(
struct super_block *sb,
@@ -1345,37 +1386,9 @@ xfs_fs_remount(

/* rw -> ro */
if (!(mp->m_flags & XFS_MOUNT_RDONLY) && (*flags & SB_RDONLY)) {
- /*
- * Cancel background eofb scanning so it cannot race with the
- * final log force+buftarg wait and deadlock the remount.
- */
- xfs_stop_block_reaping(mp);
-
- /* Get rid of any leftover CoW reservations... */
- error = xfs_icache_free_cowblocks(mp, NULL);
- if (error) {
- xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
- return error;
- }
-
- /* Free the per-AG metadata reservation pool. */
- error = xfs_fs_unreserve_ag_blocks(mp);
- if (error) {
- xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
+ error = xfs_remount_ro(mp);
+ if (error)
return error;
- }
-
- /*
- * Before we sync the metadata, we need to free up the reserve
- * block pool so that the used block count in the superblock on
- * disk is correct at the end of the remount. Stash the current
- * reserve pool size so that if we get remounted rw, we can
- * return it to the same size.
- */
- xfs_save_resvblks(mp);
-
- xfs_quiesce_attr(mp);
- mp->m_flags |= XFS_MOUNT_RDONLY;
}

return 0;