Merge tag 'xfs-for-linus-3.15-rc1' of git://oss.sgi.com/xfs/xfs

Pull xfs update from Dave Chinner:
 "There are a couple of new fallocate features in this request - it was
  decided that it was easiest to push them through the XFS tree using
  topic branches and have the ext4 support be based on those branches.
  Hence you may see some overlap with the ext4 tree merge depending on
  how they including those topic branches into their tree.  Other than
  that, there is O_TMPFILE support, some cleanups and bug fixes.

  The main changes in the XFS tree for 3.15-rc1 are:

   - O_TMPFILE support
   - allowing AIO+DIO writes beyond EOF
   - FALLOC_FL_COLLAPSE_RANGE support for fallocate syscall and XFS
     implementation
   - FALLOC_FL_ZERO_RANGE support for fallocate syscall and XFS
     implementation
   - IO verifier cleanup and rework
   - stack usage reduction changes
   - vm_map_ram NOIO context fixes to remove lockdep warings
   - various bug fixes and cleanups"

* tag 'xfs-for-linus-3.15-rc1' of git://oss.sgi.com/xfs/xfs: (34 commits)
  xfs: fix directory hash ordering bug
  xfs: extra semi-colon breaks a condition
  xfs: Add support for FALLOC_FL_ZERO_RANGE
  fs: Introduce FALLOC_FL_ZERO_RANGE flag for fallocate
  xfs: inode log reservations are still too small
  xfs: xfs_check_page_type buffer checks need help
  xfs: avoid AGI/AGF deadlock scenario for inode chunk allocation
  xfs: use NOIO contexts for vm_map_ram
  xfs: don't leak EFSBADCRC to userspace
  xfs: fix directory inode iolock lockdep false positive
  xfs: allocate xfs_da_args to reduce stack footprint
  xfs: always do log forces via the workqueue
  xfs: modify verifiers to differentiate CRC from other errors
  xfs: print useful caller information in xfs_error_report
  xfs: add xfs_verifier_error()
  xfs: add helper for updating checksums on xfs_bufs
  xfs: add helper for verifying checksums on xfs_bufs
  xfs: Use defines for CRC offsets in all cases
  xfs: skip pointless CRC updates after verifier failures
  xfs: Add support FALLOC_FL_COLLAPSE_RANGE for fallocate
  ...

1 files changed, 96 insertions, 1 deletions

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index f264616080c..01f6a646caa 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1349,7 +1349,6 @@ xfs_free_file_space(
 		 * the freeing of the space succeeds at ENOSPC.
 		 */
 		tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
-		tp->t_flags |= XFS_TRANS_RESERVE;
 		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write, resblks, 0);
 
 		/*
@@ -1468,6 +1467,102 @@ out:
 }
 
 /*
+ * xfs_collapse_file_space()
+ *	This routine frees disk space and shift extent for the given file.
+ *	The first thing we do is to free data blocks in the specified range
+ *	by calling xfs_free_file_space(). It would also sync dirty data
+ *	and invalidate page cache over the region on which collapse range
+ *	is working. And Shift extent records to the left to cover a hole.
+ * RETURNS:
+ *	0 on success
+ *	errno on error
+ *
+ */
+int
+xfs_collapse_file_space(
+	struct xfs_inode	*ip,
+	xfs_off_t		offset,
+	xfs_off_t		len)
+{
+	int			done = 0;
+	struct xfs_mount	*mp = ip->i_mount;
+	struct xfs_trans	*tp;
+	int			error;
+	xfs_extnum_t		current_ext = 0;
+	struct xfs_bmap_free	free_list;
+	xfs_fsblock_t		first_block;
+	int			committed;
+	xfs_fileoff_t		start_fsb;
+	xfs_fileoff_t		shift_fsb;
+
+	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
+
+	trace_xfs_collapse_file_space(ip);
+
+	start_fsb = XFS_B_TO_FSB(mp, offset + len);
+	shift_fsb = XFS_B_TO_FSB(mp, len);
+
+	error = xfs_free_file_space(ip, offset, len);
+	if (error)
+		return error;
+
+	while (!error && !done) {
+		tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
+		tp->t_flags |= XFS_TRANS_RESERVE;
+		/*
+		 * We would need to reserve permanent block for transaction.
+		 * This will come into picture when after shifting extent into
+		 * hole we found that adjacent extents can be merged which
+		 * may lead to freeing of a block during record update.
+		 */
+		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write,
+				XFS_DIOSTRAT_SPACE_RES(mp, 0), 0);
+		if (error) {
+			ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
+			xfs_trans_cancel(tp, 0);
+			break;
+		}
+
+		xfs_ilock(ip, XFS_ILOCK_EXCL);
+		error = xfs_trans_reserve_quota(tp, mp, ip->i_udquot,
+				ip->i_gdquot, ip->i_pdquot,
+				XFS_DIOSTRAT_SPACE_RES(mp, 0), 0,
+				XFS_QMOPT_RES_REGBLKS);
+		if (error)
+			goto out;
+
+		xfs_trans_ijoin(tp, ip, 0);
+
+		xfs_bmap_init(&free_list, &first_block);
+
+		/*
+		 * We are using the write transaction in which max 2 bmbt
+		 * updates are allowed
+		 */
+		error = xfs_bmap_shift_extents(tp, ip, &done, start_fsb,
+					       shift_fsb, &current_ext,
+					       &first_block, &free_list,
+					       XFS_BMAP_MAX_SHIFT_EXTENTS);
+		if (error)
+			goto out;
+
+		error = xfs_bmap_finish(&tp, &free_list, &committed);
+		if (error)
+			goto out;
+
+		error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
+		xfs_iunlock(ip, XFS_ILOCK_EXCL);
+	}
+
+	return error;
+
+out:
+	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
+	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+	return error;
+}
+
+/*
  * We need to check that the format of the data fork in the temporary inode is
  * valid for the target inode before doing the swap. This is not a problem with
  * attr1 because of the fixed fork offset, but attr2 has a dynamically sized