xfs: move helpers that lock and unlock two inodes against userspace IO

Move the double-inode locking helpers to xfs_inode.c since they're not
specific to reflink.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>

1 files changed, 2 insertions, 95 deletions

diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index c1f2222ffece..aac83f9d6107 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -1230,99 +1230,6 @@ xfs_reflink_remap_blocks(
 }
 
 /*
- * Grab the exclusive iolock for a data copy from src to dest, making sure to
- * abide vfs locking order (lowest pointer value goes first) and breaking the
- * layout leases before proceeding.  The loop is needed because we cannot call
- * the blocking break_layout() with the iolocks held, and therefore have to
- * back out both locks.
- */
-static int
-xfs_iolock_two_inodes_and_break_layout(
-	struct inode		*src,
-	struct inode		*dest)
-{
-	int			error;
-
-	if (src > dest)
-		swap(src, dest);
-
-retry:
-	/* Wait to break both inodes' layouts before we start locking. */
-	error = break_layout(src, true);
-	if (error)
-		return error;
-	if (src != dest) {
-		error = break_layout(dest, true);
-		if (error)
-			return error;
-	}
-
-	/* Lock one inode and make sure nobody got in and leased it. */
-	inode_lock(src);
-	error = break_layout(src, false);
-	if (error) {
-		inode_unlock(src);
-		if (error == -EWOULDBLOCK)
-			goto retry;
-		return error;
-	}
-
-	if (src == dest)
-		return 0;
-
-	/* Lock the other inode and make sure nobody got in and leased it. */
-	inode_lock_nested(dest, I_MUTEX_NONDIR2);
-	error = break_layout(dest, false);
-	if (error) {
-		inode_unlock(src);
-		inode_unlock(dest);
-		if (error == -EWOULDBLOCK)
-			goto retry;
-		return error;
-	}
-
-	return 0;
-}
-
-/*
- * Lock two files so that userspace cannot initiate I/O via file syscalls or
- * mmap activity.
- */
-static int
-xfs_reflink_remap_lock(
-	struct xfs_inode	*ip1,
-	struct xfs_inode	*ip2)
-{
-	int			ret;
-
-	ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2));
-	if (ret)
-		return ret;
-	if (ip1 == ip2)
-		xfs_ilock(ip1, XFS_MMAPLOCK_EXCL);
-	else
-		xfs_lock_two_inodes(ip1, XFS_MMAPLOCK_EXCL,
-				    ip2, XFS_MMAPLOCK_EXCL);
-	return 0;
-}
-
-/* Unlock both files to allow IO and mmap activity. */
-void
-xfs_reflink_remap_unlock(
-	struct xfs_inode	*ip1,
-	struct xfs_inode	*ip2)
-{
-	bool			same_inode = (ip1 == ip2);
-
-	xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
-	if (!same_inode)
-		xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
-	inode_unlock(VFS_I(ip2));
-	if (!same_inode)
-		inode_unlock(VFS_I(ip1));
-}
-
-/*
  * If we're reflinking to a point past the destination file's EOF, we must
  * zero any speculative post-EOF preallocations that sit between the old EOF
  * and the destination file offset.
@@ -1387,7 +1294,7 @@ xfs_reflink_remap_prep(
 	int			ret;
 
 	/* Lock both files against IO */
-	ret = xfs_reflink_remap_lock(src, dest);
+	ret = xfs_ilock2_io_mmap(src, dest);
 	if (ret)
 		return ret;
 
@@ -1440,7 +1347,7 @@ xfs_reflink_remap_prep(
 
 	return 0;
 out_unlock:
-	xfs_reflink_remap_unlock(src, dest);
+	xfs_iunlock2_io_mmap(src, dest);
 	return ret;
 }