xfs: better xfs_trans_alloc interface

Merge xfs_trans_reserve and xfs_trans_alloc into a single function call
that returns a transaction with all the required log and block reservations,
and which allows passing transaction flags directly to avoid the cumbersome
_xfs_trans_alloc interface.

While we're at it we also get rid of the transaction type argument that has
been superflous since we stopped supporting the non-CIL logging mode.  The
guts of it will be removed in another patch.

[dchinner: fixed transaction leak in error path in xfs_setattr_nonsize]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 17 insertions, 36 deletions

diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index d81bdc080370..58391355a44d 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -132,6 +132,7 @@ xfs_iomap_write_direct(
 	int		error;
 	int		lockmode;
 	int		bmapi_flags = XFS_BMAPI_PREALLOC;
+	uint		tflags = 0;
 
 	rt = XFS_IS_REALTIME_INODE(ip);
 	extsz = xfs_get_extsz_hint(ip);
@@ -192,11 +193,6 @@ xfs_iomap_write_direct(
 		return error;
 
 	/*
-	 * Allocate and setup the transaction
-	 */
-	tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
-
-	/*
 	 * For DAX, we do not allocate unwritten extents, but instead we zero
 	 * the block before we commit the transaction.  Ideally we'd like to do
 	 * this outside the transaction context, but if we commit and then crash
@@ -209,23 +205,17 @@ xfs_iomap_write_direct(
 	 * the reserve block pool for bmbt block allocation if there is no space
 	 * left but we need to do unwritten extent conversion.
 	 */
-
 	if (IS_DAX(VFS_I(ip))) {
 		bmapi_flags = XFS_BMAPI_CONVERT | XFS_BMAPI_ZERO;
 		if (ISUNWRITTEN(imap)) {
-			tp->t_flags |= XFS_TRANS_RESERVE;
+			tflags |= XFS_TRANS_RESERVE;
 			resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0) << 1;
 		}
 	}
-	error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write,
-				  resblks, resrtextents);
-	/*
-	 * Check for running out of space, note: need lock to return
-	 */
-	if (error) {
-		xfs_trans_cancel(tp);
+	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, resrtextents,
+			tflags, &tp);
+	if (error)
 		return error;
-	}
 
 	lockmode = XFS_ILOCK_EXCL;
 	xfs_ilock(ip, lockmode);
@@ -726,15 +716,13 @@ xfs_iomap_write_allocate(
 
 		nimaps = 0;
 		while (nimaps == 0) {
-			tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
-			tp->t_flags |= XFS_TRANS_RESERVE;
 			nres = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK);
-			error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write,
-						  nres, 0);
-			if (error) {
-				xfs_trans_cancel(tp);
+
+			error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, nres,
+					0, XFS_TRANS_RESERVE, &tp);
+			if (error)
 				return error;
-			}
+
 			xfs_ilock(ip, XFS_ILOCK_EXCL);
 			xfs_trans_ijoin(tp, ip, 0);
 
@@ -878,25 +866,18 @@ xfs_iomap_write_unwritten(
 
 	do {
 		/*
-		 * set up a transaction to convert the range of extents
+		 * Set up a transaction to convert the range of extents
 		 * from unwritten to real. Do allocations in a loop until
 		 * we have covered the range passed in.
 		 *
-		 * Note that we open code the transaction allocation here
-		 * to pass KM_NOFS--we can't risk to recursing back into
-		 * the filesystem here as we might be asked to write out
-		 * the same inode that we complete here and might deadlock
-		 * on the iolock.
+		 * Note that we can't risk to recursing back into the filesystem
+		 * here as we might be asked to write out the same inode that we
+		 * complete here and might deadlock on the iolock.
 		 */
-		sb_start_intwrite(mp->m_super);
-		tp = _xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE, KM_NOFS);
-		tp->t_flags |= XFS_TRANS_RESERVE | XFS_TRANS_FREEZE_PROT;
-		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write,
-					  resblks, 0);
-		if (error) {
-			xfs_trans_cancel(tp);
+		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0,
+				XFS_TRANS_RESERVE | XFS_TRANS_NOFS, &tp);
+		if (error)
 			return error;
-		}
 
 		xfs_ilock(ip, XFS_ILOCK_EXCL);
 		xfs_trans_ijoin(tp, ip, 0);