From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
When we're freezing the filesystem, free all the COW staging extents
before we shut the log down so that we can minimize the amount of
recovery work that will be necessary during the next mount.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
fs/xfs/xfs_icache.c | 17 ++++++++++++-----
fs/xfs/xfs_super.c | 18 ++++++++++++++++++
2 files changed, 30 insertions(+), 5 deletions(-)
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index 245483cc282b..36d986087abb 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -1741,6 +1741,7 @@ xfs_inode_free_cowblocks(
void *args)
{
struct xfs_eofblocks *eofb = args;
+ uint lock_mode = 0;
int match;
int ret = 0;
@@ -1761,9 +1762,15 @@ xfs_inode_free_cowblocks(
return 0;
}
- /* Free the CoW blocks */
- xfs_ilock(ip, XFS_IOLOCK_EXCL);
- xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
+ /*
+ * Free the CoW blocks. We don't need to lock the inode if we're in
+ * the process of freezing the filesystem because we've already locked
+ * out writes and page faults.
+ */
+ if (ip->i_mount->m_super->s_writers.frozen == SB_UNFROZEN)
+ lock_mode = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;
+ if (lock_mode)
+ xfs_ilock(ip, lock_mode);
/*
* Check again, nobody else should be able to dirty blocks or change
@@ -1772,8 +1779,8 @@ xfs_inode_free_cowblocks(
if (xfs_prep_free_cowblocks(ip))
ret = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, false);
- xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
- xfs_iunlock(ip, XFS_IOLOCK_EXCL);
+ if (lock_mode)
+ xfs_iunlock(ip, lock_mode);
return ret;
}
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 6903b36eac5d..bb4953cfd683 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1102,6 +1102,24 @@ xfs_fs_sync_fs(
if (!wait)
return 0;
+ /*
+ * If we're in the middle of freezing the filesystem, this is our last
+ * chance to run regular transactions. Clear all the COW staging
+ * extents so that we can freeze the filesystem with as little recovery
+ * work to do at the next mount as possible. It's safe to do this
+ * without locking inodes because the freezer code flushed all the
+ * dirty data from the page cache and locked out writes and page faults.
+ */
+ if (sb->s_writers.frozen == SB_FREEZE_PAGEFAULT) {
+ int error;
+
+ error = xfs_icache_free_cowblocks(mp, NULL);
+ if (error) {
+ xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
+ return error;
+ }
+ }
+
xfs_log_force(mp, XFS_LOG_SYNC);
if (laptop_mode) {
/*
