xfs: split xfs_itruncate_finish

Split the guts of xfs_itruncate_finish that loop over the existing extents
and calls xfs_bunmapi on them into a new helper, xfs_itruncate_externs.
Make xfs_attr_inactive call it directly instead of xfs_itruncate_finish,
which allows to simplify the latter a lot, by only letting it deal with
the data fork.  As a result xfs_itruncate_finish is renamed to
xfs_itruncate_data to make its use case more obvious.

Also remove the sync parameter from xfs_itruncate_data, which has been
unessecary since the introduction of the busy extent list in 2002, and
completely dead code since 2003 when the XFS_BMAPI_ASYNC parameter was
made a no-op.

I can't actually see why the xfs_attr_inactive needs to set the transaction
sync, but let's keep this patch simple and without changes in behaviour.

Also avoid passing a useless argument to xfs_isize_check, and make it
private to xfs_inode.c.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

fs/xfs/linux-2.6/xfs_iops.c

@@ -879,15 +879,7 @@ xfs_setattr_size(
 		ip->i_size = iattr->ia_size;
 	} else if (iattr->ia_size <= ip->i_size ||
 		   (iattr->ia_size == 0 && ip->i_d.di_nextents)) {
-		/*
-		 * Signal a sync transaction unless we are truncating an
-		 * already unlinked file on a wsync filesystem.
-		 */
-		error = xfs_itruncate_finish(&tp, ip, iattr->ia_size,
-				    XFS_DATA_FORK,
-				    ((ip->i_d.di_nlink != 0 ||
-				      !(mp->m_flags & XFS_MOUNT_WSYNC))
-				     ? 1 : 0));
+		error = xfs_itruncate_data(&tp, ip, iattr->ia_size);
 		if (error)
 			goto out_trans_abort;
 

fs/xfs/linux-2.6/xfs_trace.h

@@ -1055,8 +1055,8 @@ DECLARE_EVENT_CLASS(xfs_itrunc_class,
 DEFINE_EVENT(xfs_itrunc_class, name, \
 	TP_PROTO(struct xfs_inode *ip, xfs_fsize_t new_size), \
 	TP_ARGS(ip, new_size))
-DEFINE_ITRUNC_EVENT(xfs_itruncate_finish_start);
-DEFINE_ITRUNC_EVENT(xfs_itruncate_finish_end);
+DEFINE_ITRUNC_EVENT(xfs_itruncate_data_start);
+DEFINE_ITRUNC_EVENT(xfs_itruncate_data_end);
 
 TRACE_EVENT(xfs_pagecache_inval,
 	TP_PROTO(struct xfs_inode *ip, xfs_off_t start, xfs_off_t finish),

fs/xfs/quota/xfs_qm_syscalls.c

@@ -263,7 +263,7 @@ xfs_qm_scall_trunc_qfile(
 	xfs_ilock(ip, XFS_ILOCK_EXCL);
 	xfs_trans_ijoin(tp, ip);
 
-	error = xfs_itruncate_finish(&tp, ip, 0, XFS_DATA_FORK, 1);
+	error = xfs_itruncate_data(&tp, ip, 0);
 	if (error) {
 		xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES |
 				     XFS_TRANS_ABORT);

fs/xfs/xfs_attr.c

@@ -822,17 +822,21 @@ xfs_attr_inactive(xfs_inode_t *dp)
 	error = xfs_attr_root_inactive(&trans, dp);
 	if (error)
 		goto out;
+
 	/*
-	 * signal synchronous inactive transactions unless this
-	 * is a synchronous mount filesystem in which case we
-	 * know that we're here because we've been called out of
-	 * xfs_inactive which means that the last reference is gone
-	 * and the unlink transaction has already hit the disk so
-	 * async inactive transactions are safe.
+	 * Signal synchronous inactive transactions unless this is a
+	 * synchronous mount filesystem in which case we know that we're here
+	 * because we've been called out of xfs_inactive which means that the
+	 * last reference is gone and the unlink transaction has already hit
+	 * the disk so async inactive transactions are safe.
 	 */
-	if ((error = xfs_itruncate_finish(&trans, dp, 0LL, XFS_ATTR_FORK,
-				(!(mp->m_flags & XFS_MOUNT_WSYNC)
-				 ? 1 : 0))))
+	if (!(mp->m_flags & XFS_MOUNT_WSYNC)) {
+		if (dp->i_d.di_anextents > 0)
+			xfs_trans_set_sync(trans);
+	}
+
+	error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
+	if (error)
 		goto out;
 
 	/*

fs/xfs/xfs_inode.h

@@ -491,8 +491,10 @@ uint		xfs_ip2xflags(struct xfs_inode *);
 uint		xfs_dic2xflags(struct xfs_dinode *);
 int		xfs_ifree(struct xfs_trans *, xfs_inode_t *,
 			   struct xfs_bmap_free *);
-int		xfs_itruncate_finish(struct xfs_trans **, xfs_inode_t *,
-				     xfs_fsize_t, int, int);
+int		xfs_itruncate_extents(struct xfs_trans **, struct xfs_inode *,
+				      int, xfs_fsize_t);
+int		xfs_itruncate_data(struct xfs_trans **, struct xfs_inode *,
+				   xfs_fsize_t);
 int		xfs_iunlink(struct xfs_trans *, xfs_inode_t *);
 
 void		xfs_iext_realloc(xfs_inode_t *, int, int);
@@ -568,13 +570,6 @@ void		xfs_iext_irec_update_extoffs(xfs_ifork_t *, int, int);
 
 #define xfs_ipincount(ip)	((unsigned int) atomic_read(&ip->i_pincount))
 
-#ifdef DEBUG
-void		xfs_isize_check(struct xfs_mount *, struct xfs_inode *,
-				xfs_fsize_t);
-#else	/* DEBUG */
-#define xfs_isize_check(mp, ip, isize)
-#endif	/* DEBUG */
-
 #if defined(DEBUG)
 void		xfs_inobp_check(struct xfs_mount *, struct xfs_buf *);
 #else

fs/xfs/xfs_vnodeops.c

@@ -220,15 +220,12 @@ xfs_free_eofblocks(
 		xfs_ilock(ip, XFS_ILOCK_EXCL);
 		xfs_trans_ijoin(tp, ip);
 
-		error = xfs_itruncate_finish(&tp, ip,
-					     ip->i_size,
-					     XFS_DATA_FORK,
-					     0);
-		/*
-		 * If we get an error at this point we
-		 * simply don't bother truncating the file.
-		 */
+		error = xfs_itruncate_data(&tp, ip, ip->i_size);
 		if (error) {
+			/*
+			 * If we get an error at this point we simply don't
+			 * bother truncating the file.
+			 */
 			xfs_trans_cancel(tp,
 					 (XFS_TRANS_RELEASE_LOG_RES |
 					  XFS_TRANS_ABORT));
@@ -665,16 +662,7 @@ xfs_inactive(
 		xfs_ilock(ip, XFS_ILOCK_EXCL);
 		xfs_trans_ijoin(tp, ip);
 
-		/*
-		 * normally, we have to run xfs_itruncate_finish sync.
-		 * But if filesystem is wsync and we're in the inactive
-		 * path, then we know that nlink == 0, and that the
-		 * xaction that made nlink == 0 is permanently committed
-		 * since xfs_remove runs as a synchronous transaction.
-		 */
-		error = xfs_itruncate_finish(&tp, ip, 0, XFS_DATA_FORK,
-				(!(mp->m_flags & XFS_MOUNT_WSYNC) ? 1 : 0));
-
+		error = xfs_itruncate_data(&tp, ip, 0);
 		if (error) {
 			xfs_trans_cancel(tp,
 				XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);