xfs: factor out nodiscard helpers

The changes to skip discards of speculative preallocation and
unwritten extents introduced several new wrapper functions through
the bunmapi -> extent free codepath to reduce churn in all of the
associated callers. In several cases, these wrappers simply toggle a
single flag to skip or not skip discards for the resulting blocks.

The explicit _nodiscard() wrappers for such an isolated set of
callers is a bit overkill. Kill off these wrappers and replace with
the calls to the underlying functions in the contexts that need to
control discard behavior. Retain the wrappers that preserve the
original calling conventions to serve the original purpose of
reducing code churn.

This is a refactoring patch and does not change behavior.

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

fs/xfs/libxfs/xfs_alloc.h

@@ -210,17 +210,6 @@ xfs_free_extent(
 	return __xfs_free_extent(tp, bno, len, oinfo, type, false);
 }
 
-static inline int
-xfs_free_extent_nodiscard(
-	struct xfs_trans	*tp,
-	xfs_fsblock_t		bno,
-	xfs_extlen_t		len,
-	struct xfs_owner_info	*oinfo,
-	enum xfs_ag_resv_type	type)
-{
-	return __xfs_free_extent(tp, bno, len, oinfo, type, true);
-}
-
 int				/* error */
 xfs_alloc_lookup_le(
 	struct xfs_btree_cur	*cur,	/* btree cursor */

fs/xfs/libxfs/xfs_bmap.c

@@ -5116,15 +5116,10 @@ xfs_bmap_del_extent_real(
 			if (error)
 				goto done;
 		} else {
-			if ((bflags & XFS_BMAPI_NODISCARD) ||
-			    (del->br_state == XFS_EXT_UNWRITTEN)) {
-				xfs_bmap_add_free_nodiscard(mp, dfops,
-					del->br_startblock, del->br_blockcount,
-					NULL);
-			} else {
-				xfs_bmap_add_free(mp, dfops, del->br_startblock,
-					del->br_blockcount, NULL);
-			}
+			__xfs_bmap_add_free(mp, dfops, del->br_startblock,
+					del->br_blockcount, NULL,
+					(bflags & XFS_BMAPI_NODISCARD) ||
+					del->br_state == XFS_EXT_UNWRITTEN);
 		}
 	}
 

fs/xfs/libxfs/xfs_bmap.h

@@ -260,17 +260,6 @@ xfs_bmap_add_free(
 	__xfs_bmap_add_free(mp, dfops, bno, len, oinfo, false);
 }
 
-static inline void
-xfs_bmap_add_free_nodiscard(
-	struct xfs_mount		*mp,
-	struct xfs_defer_ops		*dfops,
-	xfs_fsblock_t			bno,
-	xfs_filblks_t			len,
-	struct xfs_owner_info		*oinfo)
-{
-	__xfs_bmap_add_free(mp, dfops, bno, len, oinfo, true);
-}
-
 enum xfs_bmap_intent_type {
 	XFS_BMAP_MAP = 1,
 	XFS_BMAP_UNMAP,

fs/xfs/xfs_bmap_util.c

@@ -871,8 +871,8 @@ xfs_free_eofblocks(
 		 * contents of the file are flushed to disk then the files
 		 * may be full of holes (ie NULL files bug).
 		 */
-		error = xfs_itruncate_extents_nodiscard(&tp, ip, XFS_DATA_FORK,
-							XFS_ISIZE(ip));
+		error = xfs_itruncate_extents_flags(&tp, ip, XFS_DATA_FORK,
+					XFS_ISIZE(ip), XFS_BMAPI_NODISCARD);
 		if (error) {
 			/*
 			 * If we get an error at this point we simply don't

fs/xfs/xfs_inode.c

@@ -1548,12 +1548,12 @@ xfs_itruncate_clear_reflink_flags(
  * dirty on error so that transactions can be easily aborted if possible.
  */
 int
-__xfs_itruncate_extents(
+xfs_itruncate_extents_flags(
 	struct xfs_trans	**tpp,
 	struct xfs_inode	*ip,
 	int			whichfork,
 	xfs_fsize_t		new_size,
-	bool			skip_discard)
+	int			flags)
 {
 	struct xfs_mount	*mp = ip->i_mount;
 	struct xfs_trans	*tp = *tpp;
@@ -1564,7 +1564,6 @@ __xfs_itruncate_extents(
 	xfs_filblks_t		unmap_len;
 	int			error = 0;
 	int			done = 0;
-	int			flags;
 
 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 	ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
@@ -1577,9 +1576,7 @@ __xfs_itruncate_extents(
 
 	trace_xfs_itruncate_extents_start(ip, new_size);
 
-	flags = xfs_bmapi_aflag(whichfork);
-	if (skip_discard)
-		flags |= XFS_BMAPI_NODISCARD;
+	flags |= xfs_bmapi_aflag(whichfork);
 
 	/*
 	 * Since it is possible for space to become allocated beyond

fs/xfs/xfs_inode.h

@@ -415,8 +415,8 @@ uint		xfs_ilock_attr_map_shared(struct xfs_inode *);
 uint		xfs_ip2xflags(struct xfs_inode *);
 int		xfs_ifree(struct xfs_trans *, xfs_inode_t *,
 			   struct xfs_defer_ops *);
-int		__xfs_itruncate_extents(struct xfs_trans **, struct xfs_inode *,
-				        int, xfs_fsize_t, bool);
+int		xfs_itruncate_extents_flags(struct xfs_trans **,
+				struct xfs_inode *, int, xfs_fsize_t, int);
 void		xfs_iext_realloc(xfs_inode_t *, int, int);
 
 void		xfs_iunpin_wait(xfs_inode_t *);
@@ -440,17 +440,7 @@ xfs_itruncate_extents(
 	int			whichfork,
 	xfs_fsize_t		new_size)
 {
-	return __xfs_itruncate_extents(tpp, ip, whichfork, new_size, false);
-}
-
-static inline int
-xfs_itruncate_extents_nodiscard(
-	struct xfs_trans	**tpp,
-	struct xfs_inode	*ip,
-	int			whichfork,
-	xfs_fsize_t		new_size)
-{
-	return __xfs_itruncate_extents(tpp, ip, whichfork, new_size, true);
+	return xfs_itruncate_extents_flags(tpp, ip, whichfork, new_size, 0);
 }
 
 /* from xfs_file.c */

fs/xfs/xfs_trans_extfree.c

@@ -80,13 +80,8 @@ xfs_trans_free_extent(
 
 	trace_xfs_bmap_free_deferred(tp->t_mountp, agno, 0, agbno, ext_len);
 
-	if (skip_discard)
-		error = xfs_free_extent_nodiscard(tp, start_block, ext_len,
-						  oinfo, XFS_AG_RESV_NONE);
-	else
-		error = xfs_free_extent(tp, start_block, ext_len, oinfo,
-					XFS_AG_RESV_NONE);
-
+	error = __xfs_free_extent(tp, start_block, ext_len,
+				  oinfo, XFS_AG_RESV_NONE, skip_discard);
 	/*
 	 * Mark the transaction dirty, even on error. This ensures the
 	 * transaction is aborted, which: