Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
index e3b3e9d..ced1e65 100644
--- a/fs/xfs/libxfs/xfs_btree.h
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -301,8 +301,7 @@
 xfs_btree_get_bufl(
 	struct xfs_mount	*mp,	/* file system mount point */
 	struct xfs_trans	*tp,	/* transaction pointer */
-	xfs_fsblock_t		fsbno,	/* file system block number */
-	uint			lock);	/* lock flags for get_buf */
+	xfs_fsblock_t		fsbno);	/* file system block number */
 
 /*
  * Get a buffer for the block, return it with no data read.
@@ -313,8 +312,7 @@
 	struct xfs_mount	*mp,	/* file system mount point */
 	struct xfs_trans	*tp,	/* transaction pointer */
 	xfs_agnumber_t		agno,	/* allocation group number */
-	xfs_agblock_t		agbno,	/* allocation group block number */
-	uint			lock);	/* lock flags for get_buf */
+	xfs_agblock_t		agbno);	/* allocation group block number */
 
 /*
  * Check for the cursor referring to the last block at the given level.
@@ -345,7 +343,6 @@
 	struct xfs_mount	*mp,	/* file system mount point */
 	struct xfs_trans	*tp,	/* transaction pointer */
 	xfs_fsblock_t		fsbno,	/* file system block number */
-	uint			lock,	/* lock flags for read_buf */
 	struct xfs_buf		**bpp,	/* buffer for fsbno */
 	int			refval,	/* ref count value for buffer */
 	const struct xfs_buf_ops *ops);
@@ -383,8 +380,7 @@
 	xfs_btnum_t	btnum,
 	__u16		level,
 	__u16		numrecs,
-	__u64		owner,
-	unsigned int	flags);
+	__u64		owner);
 
 void
 xfs_btree_init_block_int(
@@ -468,9 +464,13 @@
 uint xfs_btree_compute_maxlevels(uint *limits, unsigned long len);
 unsigned long long xfs_btree_calc_size(uint *limits, unsigned long long len);
 
-/* return codes */
-#define XFS_BTREE_QUERY_RANGE_CONTINUE	0	/* keep iterating */
-#define XFS_BTREE_QUERY_RANGE_ABORT	1	/* stop iterating */
+/*
+ * Return codes for the query range iterator function are 0 to continue
+ * iterating, and non-zero to stop iterating.  Any non-zero value will be
+ * passed up to the _query_range caller.  The special value -ECANCELED can be
+ * used to stop iteration, because _query_range never generates that error
+ * code on its own.
+ */
 typedef int (*xfs_btree_query_range_fn)(struct xfs_btree_cur *cur,
 		union xfs_btree_rec *rec, void *priv);