xfs: consolidate superblock logging functions
We now have several superblock loggin functions that are identical
except for the transaction reservation and whether it shoul dbe a
synchronous transaction or not. Consolidate these all into a single
function, a single reserveration and a sync flag and call it
xfs_sync_sb().
Also, xfs_mod_sb() is not really a modification function - it's the
operation of logging the superblock buffer. hence change the name of
it to reflect this.
Note that we have to change the mp->m_update_flags that are passed
around at mount time to a boolean simply to indicate a superblock
update is needed.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index e408bf5..2b8dcf2 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -33,6 +33,7 @@
#include "xfs_fsops.h"
#include "xfs_cksum.h"
#include "xfs_sysfs.h"
+#include "xfs_sb.h"
kmem_zone_t *xfs_log_ticket_zone;
@@ -1290,9 +1291,20 @@
struct xfs_mount *mp = log->l_mp;
/* dgc: errors ignored - not fatal and nowhere to report them */
- if (xfs_log_need_covered(mp))
- xfs_fs_log_dummy(mp);
- else
+ if (xfs_log_need_covered(mp)) {
+ /*
+ * Dump a transaction into the log that contains no real change.
+ * This is needed to stamp the current tail LSN into the log
+ * during the covering operation.
+ *
+ * We cannot use an inode here for this - that will push dirty
+ * state back up into the VFS and then periodic inode flushing
+ * will prevent log covering from making progress. Hence we
+ * synchronously log the superblock instead to ensure the
+ * superblock is immediately unpinned and can be written back.
+ */
+ xfs_sync_sb(mp, true);
+ } else
xfs_log_force(mp, 0);
/* start pushing all the metadata that is currently dirty */