[XFS] rework iocore infrastructure, remove some code and make it more

orthogonal. In addition, add some of the hooks for unwritten extents.

SGI Modid: 2.5.x-xfs:slinx:134603a

fs/xfs/linux/xfs_aops.c

@@ -48,6 +48,9 @@ map_blocks(
 	vnode_t			*vp = LINVFS_GET_VP(inode);
 	int			error, nmaps = 1;
 
+	if (((flags & (PBF_DIRECT|PBF_SYNC)) == PBF_DIRECT) &&
+	    (offset >= inode->i_size))
+		count = max(count, XFS_WRITE_IO_LOG);
 retry:
 	VOP_BMAP(vp, offset, count, flags, pbmapp, &nmaps, error);
 	if (flags & PBF_WRITE) {
@@ -515,7 +518,7 @@ linvfs_get_block_core(
 		/* If we are doing writes at the end of the file,
 		 * allocate in chunks
 		 */
-		if (create && (offset >= inode->i_size) && !(flags & PBF_SYNC))
+		if (create && (offset >= inode->i_size))
 			size = 1 << XFS_WRITE_IO_LOG;
 		else
 			size = 1 << inode->i_blkbits;
@@ -534,15 +537,20 @@ linvfs_get_block_core(
 		page_buf_daddr_t	bn;
 		loff_t			delta;
 
-		delta = offset - pbmap.pbm_offset;
-		delta >>= inode->i_blkbits;
+		/* For unwritten extents do not report a disk address on
+		 * the read case.
+		 */
+		if (create || ((pbmap.pbm_flags & PBMF_UNWRITTEN) == 0)) {
+			delta = offset - pbmap.pbm_offset;
+			delta >>= inode->i_blkbits;
 
-		bn = pbmap.pbm_bn >> (inode->i_blkbits - 9);
-		bn += delta;
+			bn = pbmap.pbm_bn >> (inode->i_blkbits - 9);
+			bn += delta;
 
-		bh_result->b_blocknr = bn;
-		bh_result->b_bdev = pbmap.pbm_target->pbr_bdev;
-		set_buffer_mapped(bh_result);
+			bh_result->b_blocknr = bn;
+			bh_result->b_bdev = pbmap.pbm_target->pbr_bdev;
+			set_buffer_mapped(bh_result);
+		}
 	}
 
 	/* If we previously allocated a block out beyond eof and

fs/xfs/linux/xfs_iomap.c

@@ -30,361 +30,18 @@
  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  */
 /*
- *  fs/xfs/linux/xfs_lrw.c (Linux Read Write stuff)
+ *  fs/xfs/linux/xfs_iomap.c (Linux Read Write stuff)
  *
  */
 
 #include <xfs.h>
 #include <linux/pagemap.h>
-#include <linux/capability.h>
 
 
 #define XFS_WRITEIO_ALIGN(mp,off)	(((off) >> mp->m_writeio_log) \
 						<< mp->m_writeio_log)
 #define XFS_STRAT_WRITE_IMAPS	2
-
-STATIC int xfs_iomap_read(xfs_iocore_t *, loff_t, size_t, int, page_buf_bmap_t *,
-			int *);
-STATIC int xfs_iomap_write(xfs_iocore_t *, loff_t, size_t, page_buf_bmap_t *,
-			int *, int);
-STATIC int xfs_iomap_write_delay(xfs_iocore_t *, loff_t, size_t, page_buf_bmap_t *,
-			int *, int, int);
-STATIC int xfs_iomap_write_direct(xfs_iocore_t *, loff_t, size_t, page_buf_bmap_t *,
-			int *, int, int);
-STATIC int _xfs_imap_to_bmap(xfs_iocore_t *, xfs_off_t, xfs_bmbt_irec_t *,
-			page_buf_bmap_t *, int, int);
-
-
-int
-xfs_strategy(
-	xfs_inode_t	*ip,
-	xfs_off_t	offset,
-	ssize_t		count,
-	int		flags,
-	page_buf_bmap_t	*pbmapp,
-	int		*npbmaps)
-{
-	xfs_iocore_t	*io;
-	xfs_mount_t	*mp;
-	int		error;
-	xfs_fileoff_t	offset_fsb;
-	xfs_fileoff_t	end_fsb;
-	xfs_fileoff_t	map_start_fsb;
-	xfs_fileoff_t	last_block;
-	xfs_fsblock_t	first_block;
-	xfs_bmap_free_t free_list;
-	xfs_filblks_t	count_fsb;
-	int		committed, i, loops, nimaps;
-	int		is_xfs;
-	xfs_bmbt_irec_t imap[XFS_MAX_RW_NBMAPS];
-	xfs_trans_t	*tp;
-
-	mp = ip->i_mount;
-	io = &ip->i_iocore;
-	is_xfs = IO_IS_XFS(io);
-	ASSERT((ip->i_d.di_mode & IFMT) == IFREG);
-	ASSERT(((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) != 0) ==
-	       ((io->io_flags & XFS_IOCORE_RT) != 0));
-
-	if (XFS_FORCED_SHUTDOWN(mp))
-		return XFS_ERROR(EIO);
-
-	offset_fsb = XFS_B_TO_FSBT(mp, offset);
-	nimaps = min(XFS_MAX_RW_NBMAPS, *npbmaps);
-	end_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
-	first_block = NULLFSBLOCK;
-
-	XFS_ILOCK(mp, io, XFS_ILOCK_SHARED | XFS_EXTSIZE_RD);
-	error = XFS_BMAPI(mp, NULL, io, offset_fsb,
-			(xfs_filblks_t)(end_fsb - offset_fsb),
-			XFS_BMAPI_ENTIRE, &first_block, 0, imap,
-			&nimaps, NULL);
-	XFS_IUNLOCK(mp, io, XFS_ILOCK_SHARED | XFS_EXTSIZE_RD);
-	if (error) {
-		return XFS_ERROR(error);
-	}
-
-	if (nimaps && !ISNULLSTARTBLOCK(imap[0].br_startblock)) {
-		*npbmaps = _xfs_imap_to_bmap(&ip->i_iocore, offset, imap,
-				pbmapp, nimaps, *npbmaps);
-		return 0;
-	}
-
-	/*
-	 * Make sure that the dquots are there.
-	 */
-
-	if (XFS_IS_QUOTA_ON(mp)) {
-		if (XFS_NOT_DQATTACHED(mp, ip)) {
-			if ((error = xfs_qm_dqattach(ip, 0))) {
-				return XFS_ERROR(error);
-			}
-		}
-	}
-	XFS_STATS_ADD(xfsstats.xs_xstrat_bytes,
-		XFS_FSB_TO_B(mp, imap[0].br_blockcount));
-
-	offset_fsb = imap[0].br_startoff;
-	count_fsb = imap[0].br_blockcount;
-	map_start_fsb = offset_fsb;
-	while (count_fsb != 0) {
-		/*
-		 * Set up a transaction with which to allocate the
-		 * backing store for the file.	Do allocations in a
-		 * loop until we get some space in the range we are
-		 * interested in.  The other space that might be allocated
-		 * is in the delayed allocation extent on which we sit
-		 * but before our buffer starts.
-		 */
-		nimaps = 0;
-		loops = 0;
-		while (nimaps == 0) {
-			if (is_xfs) {
-				tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
-				error = xfs_trans_reserve(tp, 0,
-						XFS_WRITE_LOG_RES(mp),
-						0, XFS_TRANS_PERM_LOG_RES,
-						XFS_WRITE_LOG_COUNT);
-				if (error) {
-					xfs_trans_cancel(tp, 0);
-					goto error0;
-				}
-				xfs_ilock(ip, XFS_ILOCK_EXCL);
-				xfs_trans_ijoin(tp, ip,
-						XFS_ILOCK_EXCL);
-				xfs_trans_ihold(tp, ip);
-			} else {
-				tp = NULL;
-				XFS_ILOCK(mp, io, XFS_ILOCK_EXCL |
-						XFS_EXTSIZE_WR);
-			}
-
-
-			/*
-			 * Allocate the backing store for the file.
-			 */
-			XFS_BMAP_INIT(&(free_list),
-					&(first_block));
-			nimaps = XFS_STRAT_WRITE_IMAPS;
-
-			/*
-			 * Ensure we don't go beyond eof - it is possible
-			 * the extents changed since we did the read call,
-			 * we dropped the ilock in the interim.
-			 */
-
-			end_fsb = XFS_B_TO_FSB(mp, XFS_SIZE(mp, io));
-			xfs_bmap_last_offset(NULL, ip, &last_block,
-				XFS_DATA_FORK);
-			last_block = XFS_FILEOFF_MAX(last_block, end_fsb);
-			if ((map_start_fsb + count_fsb) > last_block) {
-				count_fsb = last_block - map_start_fsb;
-				if (count_fsb == 0) {
-					if (is_xfs) {
-						xfs_bmap_cancel(&free_list);
-						xfs_trans_cancel(tp,
-						  (XFS_TRANS_RELEASE_LOG_RES |
-							 XFS_TRANS_ABORT));
-					}
-					XFS_IUNLOCK(mp, io, XFS_ILOCK_EXCL |
-							    XFS_EXTSIZE_WR);
-					return XFS_ERROR(EAGAIN);
-				}
-			}
-
-			error = XFS_BMAPI(mp, tp, io, map_start_fsb, count_fsb,
-					XFS_BMAPI_WRITE, &first_block, 1,
-					imap, &nimaps, &free_list);
-			if (error) {
-				xfs_bmap_cancel(&free_list);
-				xfs_trans_cancel(tp,
-					(XFS_TRANS_RELEASE_LOG_RES |
-					 XFS_TRANS_ABORT));
-				XFS_IUNLOCK(mp, io, XFS_ILOCK_EXCL |
-						    XFS_EXTSIZE_WR);
-
-				goto error0;
-			}
-
-			if (is_xfs) {
-				error = xfs_bmap_finish(&(tp), &(free_list),
-						first_block, &committed);
-				if (error) {
-					xfs_bmap_cancel(&free_list);
-					xfs_trans_cancel(tp,
-						(XFS_TRANS_RELEASE_LOG_RES |
-						XFS_TRANS_ABORT));
-					xfs_iunlock(ip, XFS_ILOCK_EXCL);
-					goto error0;
-				}
-
-				error = xfs_trans_commit(tp,
-						XFS_TRANS_RELEASE_LOG_RES,
-						NULL);
-				if (error) {
-					xfs_iunlock(ip, XFS_ILOCK_EXCL);
-					goto error0;
-				}
-			}
-
-			if (nimaps == 0) {
-				XFS_IUNLOCK(mp, io,
-						XFS_ILOCK_EXCL|XFS_EXTSIZE_WR);
-			} /* else hold 'till we maybe loop again below */
-		}
-
-		/*
-		 * See if we were able to allocate an extent that
-		 * covers at least part of the user's requested size.
-		 */
-
-		offset_fsb = XFS_B_TO_FSBT(mp, offset);
-		for (i = 0; i < nimaps; i++) {
-			int	maps;
-
-			if ((offset_fsb >= imap[i].br_startoff) &&
-			    (offset_fsb <
-			     (imap[i].br_startoff + imap[i].br_blockcount))) {
-
-				XFS_IUNLOCK(mp, io,
-						XFS_ILOCK_EXCL|XFS_EXTSIZE_WR);
-				maps = min(nimaps, *npbmaps);
-				*npbmaps = _xfs_imap_to_bmap(io, offset,
-							     &imap[i], pbmapp,
-							     maps, *npbmaps);
-				XFS_STATS_INC(xfsstats.xs_xstrat_quick);
-				return 0;
-			}
-			count_fsb -= imap[i].br_blockcount; /* for next bmapi,
-								if needed. */
-		}
-
-		/*
-		 * We didn't get an extent the caller can write into so
-		 * loop around and try starting after the last imap we got back.
-		 */
-
-		nimaps--; /* Index of last entry  */
-		ASSERT(nimaps >= 0);
-		ASSERT(offset_fsb >=
-			imap[nimaps].br_startoff + imap[nimaps].br_blockcount);
-		ASSERT(count_fsb);
-		offset_fsb =
-			imap[nimaps].br_startoff + imap[nimaps].br_blockcount;
-		map_start_fsb = offset_fsb;
-		XFS_STATS_INC(xfsstats.xs_xstrat_split);
-		XFS_IUNLOCK(mp, io, XFS_ILOCK_EXCL|XFS_EXTSIZE_WR);
-	}
-
-	ASSERT(0);	/* Should never get here */
-
- error0:
-	if (error) {
-		ASSERT(count_fsb != 0);
-		ASSERT(is_xfs || XFS_FORCED_SHUTDOWN(mp));
-	}
-
-	return XFS_ERROR(error);
-}
-
-
-/*
- * xfs_bmap() is the same as the irix xfs_bmap from xfs_rw.c
- * execpt for slight changes to the params
- */
-int
-xfs_bmap(bhv_desc_t	*bdp,
-	xfs_off_t	offset,
-	ssize_t		count,
-	int		flags,
-	page_buf_bmap_t	*pbmapp,
-	int		*npbmaps)
-{
-	xfs_inode_t	*ip;
-	int		error;
-	int		lockmode;
-	int		fsynced = 0;
-	vnode_t		*vp;
-
-	ip = XFS_BHVTOI(bdp);
-	ASSERT((ip->i_d.di_mode & IFMT) == IFREG);
-	ASSERT(((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) != 0) ==
-	       ((ip->i_iocore.io_flags & XFS_IOCORE_RT) != 0));
-
-	if (XFS_FORCED_SHUTDOWN(ip->i_iocore.io_mount))
-		return XFS_ERROR(EIO);
-
-	if (flags & PBF_READ) {
-		lockmode = xfs_ilock_map_shared(ip);
-		error = xfs_iomap_read(&ip->i_iocore, offset, count,
-				 XFS_BMAPI_ENTIRE, pbmapp, npbmaps);
-		xfs_iunlock_map_shared(ip, lockmode);
-	} else if (flags & PBF_FILE_ALLOCATE) {
-		error = xfs_strategy(ip, offset, count, flags,
-				pbmapp, npbmaps);
-	} else { /* PBF_WRITE */
-		ASSERT(flags & PBF_WRITE);
-		vp = BHV_TO_VNODE(bdp);
-		xfs_ilock(ip, XFS_ILOCK_EXCL);
-
-		/*
-		 * Make sure that the dquots are there. This doesn't hold
-		 * the ilock across a disk read.
-		 */
-
-		if (XFS_IS_QUOTA_ON(ip->i_mount)) {
-			if (XFS_NOT_DQATTACHED(ip->i_mount, ip)) {
-				if ((error = xfs_qm_dqattach(ip, XFS_QMOPT_ILOCKED))) {
-					xfs_iunlock(ip, XFS_ILOCK_EXCL);
-					return XFS_ERROR(error);
-				}
-			}
-		}
-retry:
-		error = xfs_iomap_write(&ip->i_iocore, offset, count,
-					pbmapp, npbmaps, flags);
-		/* xfs_iomap_write unlocks/locks/unlocks */
-
-		if (error == ENOSPC) {
-			switch (fsynced) {
-			case 0:
-				if (ip->i_delayed_blks) {
-					filemap_fdatawrite(LINVFS_GET_IP(vp)->i_mapping);
-					fsynced = 1;
-				} else {
-					fsynced = 2;
-					flags |= PBF_SYNC;
-				}
-				error = 0;
-				xfs_ilock(ip, XFS_ILOCK_EXCL);
-				goto retry;
-			case 1:
-				fsynced = 2;
-				if (!(flags & PBF_SYNC)) {
-					flags |= PBF_SYNC;
-					error = 0;
-					xfs_ilock(ip, XFS_ILOCK_EXCL);
-					goto retry;
-				}
-			case 2:
-				sync_blockdev(vp->v_vfsp->vfs_super->s_bdev);
-				xfs_log_force(ip->i_mount, (xfs_lsn_t)0,
-						XFS_LOG_FORCE|XFS_LOG_SYNC);
-
-				error = 0;
-/**
-				delay(HZ);
-**/
-				fsynced++;
-				xfs_ilock(ip, XFS_ILOCK_EXCL);
-				goto retry;
-			}
-		}
-	}
-
-	return XFS_ERROR(error);
-}
-
+#define XFS_WRITE_IMAPS		XFS_BMAP_MAX_NMAP
 
 STATIC int
 _xfs_imap_to_bmap(
@@ -397,7 +54,7 @@ _xfs_imap_to_bmap(
 {
 	xfs_mount_t	*mp;
 	xfs_fsize_t	nisize;
-	int		im, pbm;
+	int		pbm;
 	xfs_fsblock_t	start_block;
 
 	mp = io->io_mount;
@@ -405,7 +62,7 @@ _xfs_imap_to_bmap(
 	if (io->io_new_size > nisize)
 		nisize = io->io_new_size;
 
-	for (im=pbm=0; im < imaps && pbm < pbmaps; im++,pbmapp++,imap++,pbm++) {
+	for (pbm = 0; imaps && pbm < pbmaps; imaps--, pbmapp++, imap++, pbm++) {
 		pbmapp->pbm_target = io->io_flags & XFS_IOCORE_RT ?
 			mp->m_rtdev_targp : mp->m_ddev_targp;
 		pbmapp->pbm_offset = XFS_FSB_TO_B(mp, imap->br_startoff);
@@ -422,9 +79,8 @@ _xfs_imap_to_bmap(
 			pbmapp->pbm_flags = PBMF_DELAY;
 		} else {
 			pbmapp->pbm_bn = XFS_FSB_TO_DB_IO(io, start_block);
-			if (ISUNWRITTEN(imap)) {
+			if (ISUNWRITTEN(imap))
 				pbmapp->pbm_flags |= PBMF_UNWRITTEN;
-			}
 		}
 
 		if ((pbmapp->pbm_offset + pbmapp->pbm_bsize) >= nisize) {
@@ -436,149 +92,337 @@ _xfs_imap_to_bmap(
 	return pbm;	/* Return the number filled */
 }
 
-STATIC int
-xfs_iomap_read(
-	xfs_iocore_t	*io,
-	loff_t		offset,
-	size_t		count,
+int
+xfs_iomap(xfs_iocore_t	*io,
+	xfs_off_t	offset,
+	ssize_t		count,
 	int		flags,
 	page_buf_bmap_t	*pbmapp,
 	int		*npbmaps)
 {
-	xfs_fileoff_t	offset_fsb;
-	xfs_fileoff_t	end_fsb;
-	int		nimaps;
+	xfs_mount_t	*mp = io->io_mount;
+	xfs_fileoff_t	offset_fsb, end_fsb;
 	int		error;
-	xfs_mount_t	*mp;
-	xfs_bmbt_irec_t imap[XFS_MAX_RW_NBMAPS];
+	int		lockmode = 0;
+	xfs_bmbt_irec_t	imap;
+	int		nimaps = 1;
+	int		bmap_flags = 0;
 
-	ASSERT(ismrlocked(io->io_lock, MR_UPDATE | MR_ACCESS) != 0);
+	if (XFS_FORCED_SHUTDOWN(mp))
+		return XFS_ERROR(EIO);
+
+	switch (flags & (PBF_READ|PBF_WRITE|PBF_FILE_ALLOCATE)) {
+	case PBF_READ:
+		lockmode = XFS_LCK_MAP_SHARED(mp, io);
+		bmap_flags = XFS_BMAPI_ENTIRE;
+		break;
+	case PBF_WRITE:
+		lockmode = XFS_ILOCK_EXCL|XFS_EXTSIZE_WR;
+		bmap_flags = 0;
+		XFS_ILOCK(mp, io, lockmode);
+		break;
+	case PBF_FILE_ALLOCATE:
+		lockmode = XFS_ILOCK_SHARED|XFS_EXTSIZE_RD;
+		bmap_flags = XFS_BMAPI_ENTIRE;
+		XFS_ILOCK(mp, io, lockmode);
+		break;
+	default:
+		ASSERT(flags & (PBF_READ|PBF_WRITE|PBF_FILE_ALLOCATE));
+	}
 
-	mp = io->io_mount;
 	offset_fsb = XFS_B_TO_FSBT(mp, offset);
-	nimaps = sizeof(imap) / sizeof(imap[0]);
-	nimaps = min(nimaps, *npbmaps); /* Don't ask for more than caller has */
 	end_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
+
 	error = XFS_BMAPI(mp, NULL, io, offset_fsb,
-				(xfs_filblks_t)(end_fsb - offset_fsb),
-				flags, NULL, 0, imap,
-				&nimaps, NULL);
-	if (error) {
-		return XFS_ERROR(error);
+			(xfs_filblks_t)(end_fsb - offset_fsb) ,
+			bmap_flags,  NULL, 0, &imap,
+			&nimaps, NULL);
+
+	if (error)
+		goto out;
+
+	switch (flags & (PBF_WRITE|PBF_FILE_ALLOCATE)) {
+	case PBF_WRITE:
+		/* If we found an extent, return it */
+		if (nimaps && (imap.br_startblock != HOLESTARTBLOCK))
+			break;
+
+		if (flags & PBF_DIRECT) {
+			error = XFS_IOMAP_WRITE_DIRECT(mp, io, offset,
+					count, flags, &imap, &nimaps, nimaps);
+		} else {
+			error = XFS_IOMAP_WRITE_DELAY(mp, io, offset, count,
+					flags, &imap, &nimaps);
+		}
+		break;
+	case PBF_FILE_ALLOCATE:
+		/* If we found an extent, return it */
+		XFS_IUNLOCK(mp, io, lockmode);
+		lockmode = 0;
+
+		if (nimaps && !ISNULLSTARTBLOCK(imap.br_startblock))
+			break;
+
+		error = XFS_IOMAP_WRITE_ALLOCATE(mp, io, &imap, &nimaps);
+		break;
 	}
 
-	if(nimaps) {
-		*npbmaps = _xfs_imap_to_bmap(io, offset, imap, pbmapp, nimaps,
-			*npbmaps);
-	} else
+	if (nimaps) {
+		*npbmaps = _xfs_imap_to_bmap(io, offset, &imap,
+						pbmapp, nimaps, *npbmaps);
+	} else {
 		*npbmaps = 0;
+	}
+
+out:
+	if (lockmode)
+		XFS_IUNLOCK(mp, io, lockmode);
 	return XFS_ERROR(error);
 }
 
-/*
- * xfs_iomap_write: return pagebuf_bmap_t's telling higher layers
- *	where to write.
- * There are 2 main cases:
- *	1 the extents already exist
- *	2 must allocate.
- *	There are 3 cases when we allocate:
- *		delay allocation (doesn't really allocate or use transactions)
- *		direct allocation (no previous delay allocation)
- *		convert delay to real allocations
- */
+static int
+xfs_flush_space(
+	xfs_inode_t	*ip,
+	int		*fsynced,
+	int		*ioflags)
+{
+	vnode_t		*vp = XFS_ITOV(ip);
+
+	switch (*fsynced) {
+	case 0:
+		if (ip->i_delayed_blks) {
+			xfs_iunlock(ip, XFS_ILOCK_EXCL);
+			filemap_fdatawrite(LINVFS_GET_IP(vp)->i_mapping);
+			xfs_ilock(ip, XFS_ILOCK_EXCL);
+			*fsynced = 1;
+		} else {
+			*ioflags |= PBF_SYNC;
+			*fsynced = 2;
+		}
+		return 0;
+	case 1:
+		*fsynced = 2;
+		*ioflags |= PBF_SYNC;
+		return 0;
+	case 2:
+		xfs_iunlock(ip, XFS_ILOCK_EXCL);
+		sync_blockdev(vp->v_vfsp->vfs_super->s_bdev);
+		xfs_log_force(ip->i_mount, (xfs_lsn_t)0,
+						XFS_LOG_FORCE|XFS_LOG_SYNC);
+		xfs_ilock(ip, XFS_ILOCK_EXCL);
+		*fsynced = 3;
+		return 0;
+	}
+	return 1;
+}
 
-STATIC int
-xfs_iomap_write(
-	xfs_iocore_t	*io,
+int
+xfs_iomap_write_direct(
+	xfs_inode_t	*ip,
 	loff_t		offset,
 	size_t		count,
-	page_buf_bmap_t	*pbmapp,
-	int		*npbmaps,
-	int		ioflag)
+	int		ioflag,
+	xfs_bmbt_irec_t *ret_imap,
+	int		*nmaps,
+	int		found)
 {
-	int		maps;
-	int		error = 0;
-	int		found;
-	int		flags = 0;
+	xfs_mount_t	*mp = ip->i_mount;
+	xfs_iocore_t	*io = &ip->i_iocore;
+	xfs_fileoff_t	offset_fsb;
+	xfs_fileoff_t	last_fsb;
+	xfs_filblks_t	count_fsb;
+	xfs_fsize_t	isize;
+	xfs_fsblock_t	firstfsb;
+	int		nimaps, maps;
+	int		error;
+	int		bmapi_flag;
+	int		rt;
+	xfs_trans_t	*tp;
+	xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS], *imapp;
+	xfs_bmap_free_t free_list;
+	int		aeof;
+	xfs_filblks_t	datablocks;
+	int		committed;
+	int		numrtextents;
+	uint		resblks;
 
-	maps = *npbmaps;
-	if (!maps)
-		goto out;
+	/*
+	 * Make sure that the dquots are there. This doesn't hold
+	 * the ilock across a disk read.
+	 */
+
+	if (XFS_IS_QUOTA_ON(mp) && XFS_NOT_DQATTACHED(mp, ip)) {
+		if ((error = xfs_qm_dqattach(ip, XFS_QMOPT_ILOCKED))) {
+			return XFS_ERROR(error);
+		}
+	}
+	maps = min(XFS_WRITE_IMAPS, *nmaps);
+	nimaps = maps;
+
+	isize = ip->i_d.di_size; 
+	aeof = (offset + count) > isize;
+
+	if (io->io_new_size > isize)
+		isize = io->io_new_size;
+
+	offset_fsb = XFS_B_TO_FSBT(mp, offset);
+	last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
+	count_fsb = last_fsb - offset_fsb;
+	if (found && (ret_imap->br_startblock == HOLESTARTBLOCK)) {
+		xfs_fileoff_t	map_last_fsb;
+
+		map_last_fsb = ret_imap->br_blockcount + ret_imap->br_startoff;
+
+		if (map_last_fsb < last_fsb) {
+			last_fsb = map_last_fsb;
+			count_fsb = last_fsb - offset_fsb;
+		}
+		ASSERT(count_fsb > 0);
+	}
+
+	/*
+	 * determine if reserving space on
+	 * the data or realtime partition.
+	 */
+	if ((rt = ip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
+		int	sbrtextsize, iprtextsize;
+
+		sbrtextsize = mp->m_sb.sb_rextsize;
+		iprtextsize =
+			ip->i_d.di_extsize ? ip->i_d.di_extsize : sbrtextsize;
+		numrtextents = (count_fsb + iprtextsize - 1);
+		do_div(numrtextents, sbrtextsize);
+		datablocks = 0;
+	} else {
+		datablocks = count_fsb;
+		numrtextents = 0;
+	}
+
+	/*
+	 * allocate and setup the transaction
+	 */
+	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+	tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
+
+	resblks = XFS_DIOSTRAT_SPACE_RES(mp, datablocks);
+
+	error = xfs_trans_reserve(tp, resblks,
+			XFS_WRITE_LOG_RES(mp), numrtextents,
+			XFS_TRANS_PERM_LOG_RES,
+			XFS_WRITE_LOG_COUNT);
 
 	/*
-	 * If we have extents that are allocated for this range,
-	 * return them.
+	 * check for running out of space
 	 */
+	if (error)
+		/*
+		 * Free the transaction structure.
+		 */
+		xfs_trans_cancel(tp, 0);
+
+	xfs_ilock(ip, XFS_ILOCK_EXCL);
 
-	found = 0;
-	error = xfs_iomap_read(io, offset, count, flags, pbmapp, npbmaps);
 	if (error)
-		goto out;
+		goto error_out; /* Don't return in above if .. trans ..,
+					need lock to return */
+
+	if (XFS_IS_QUOTA_ON(mp)) {
+		if (xfs_trans_reserve_blkquota(tp, ip, resblks)) {
+			error = (EDQUOT);
+			goto error1;
+		}
+	}
+	nimaps = 1;
+
+	bmapi_flag = XFS_BMAPI_WRITE;
+	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
+	xfs_trans_ihold(tp, ip);
+
+	if (offset < ip->i_d.di_size || rt)
+		bmapi_flag |= XFS_BMAPI_PREALLOC;
 
 	/*
-	 * If we found mappings and they can just have data written
-	 * without conversion,
-	 * let the caller write these and call us again.
-	 *
-	 * If we have a HOLE or UNWRITTEN, proceed down lower to
-	 * get the space or to convert to written.
+	 * issue the bmapi() call to allocate the blocks
+	 */
+	XFS_BMAP_INIT(&free_list, &firstfsb);
+	imapp = &imap[0];
+	error = xfs_bmapi(tp, ip, offset_fsb, count_fsb,
+		bmapi_flag, &firstfsb, 0, imapp, &nimaps, &free_list);
+	if (error) {
+		goto error0;
+	}
+
+	/*
+	 * complete the transaction
 	 */
 
-	if (*npbmaps) {
-		if (!(pbmapp->pbm_flags & PBMF_HOLE)) {
-			*npbmaps = 1; /* Only checked the first one. */
-					/* We could check more, ... */
-			goto out;
-		}
+	error = xfs_bmap_finish(&tp, &free_list, firstfsb, &committed);
+	if (error) {
+		goto error0;
 	}
-	found = *npbmaps;
-	*npbmaps = maps; /* Restore to original requested */
 
-	if (ioflag & PBF_DIRECT) {
-		error = xfs_iomap_write_direct(io, offset, count, pbmapp,
-					npbmaps, ioflag, found);
-	} else {
-		error = xfs_iomap_write_delay(io, offset, count, pbmapp,
-				npbmaps, ioflag, found);
+	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
+	if (error) {
+		goto error_out;
 	}
 
-out:
-	XFS_IUNLOCK(io->io_mount, io, XFS_ILOCK_EXCL);
+	/* copy any maps to caller's array and return any error. */
+	if (nimaps == 0) {
+		error = (ENOSPC);
+		goto error_out;
+	}
+
+	*ret_imap = imap[0];
+	*nmaps = 1;
+	return 0;
+
+ error0:	/* Cancel bmap, unlock inode, and cancel trans */
+	xfs_bmap_cancel(&free_list);
+
+ error1:	/* Just cancel transaction */
+	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
+	*nmaps = 0;	/* nothing set-up here */
+
+error_out:
 	return XFS_ERROR(error);
 }
 
-STATIC int
+int
 xfs_iomap_write_delay(
-	xfs_iocore_t	*io,
+	xfs_inode_t	*ip,
 	loff_t		offset,
 	size_t		count,
-	page_buf_bmap_t	*pbmapp,
-	int		*npbmaps,
 	int		ioflag,
-	int		found)
+	xfs_bmbt_irec_t *ret_imap,
+	int		*nmaps)
 {
+	xfs_mount_t	*mp = ip->i_mount;
+	xfs_iocore_t	*io = &ip->i_iocore;
 	xfs_fileoff_t	offset_fsb;
-	xfs_fileoff_t	ioalign;
 	xfs_fileoff_t	last_fsb;
-	xfs_fileoff_t	start_fsb;
-	xfs_filblks_t	count_fsb;
-	xfs_off_t	aligned_offset;
 	xfs_fsize_t	isize;
 	xfs_fsblock_t	firstblock;
 	int		nimaps;
 	int		error;
-	int		n;
-	unsigned int	iosize;
-	xfs_mount_t	*mp;
-#define XFS_WRITE_IMAPS XFS_BMAP_MAX_NMAP
 	xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS];
 	int		aeof;
+	int		fsynced = 0;
 
-	ASSERT(ismrlocked(io->io_lock, MR_UPDATE) != 0);
+	ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE) != 0);
 
-	mp = io->io_mount;
+	/*
+	 * Make sure that the dquots are there. This doesn't hold
+	 * the ilock across a disk read.
+	 */
+
+	if (XFS_IS_QUOTA_ON(mp) && XFS_NOT_DQATTACHED(mp, ip)) {
+		if ((error = xfs_qm_dqattach(ip, XFS_QMOPT_ILOCKED))) {
+			return XFS_ERROR(error);
+		}
+	}
 
-	isize = XFS_SIZE(mp, io);
+retry:
+	isize = ip->i_d.di_size;
 	if (io->io_new_size > isize) {
 		isize = io->io_new_size;
 	}
@@ -591,50 +435,22 @@ xfs_iomap_write_delay(
 	 * then extend the allocation (and the buffer used for the write)
 	 * out to the file system's write iosize.  We clean up any extra
 	 * space left over when the file is closed in xfs_inactive().
-	 * We can only do this if we are sure that we will create buffers
-	 * over all of the space we allocate beyond the end of the file.
-	 * Not doing so would allow us to create delalloc blocks with
-	 * no pages in memory covering them.  So, we need to check that
-	 * there are not any real blocks in the area beyond the end of
-	 * the file which we are optimistically going to preallocate. If
-	 * there are then our buffers will stop when they encounter them
-	 * and we may accidentally create delalloc blocks beyond them
-	 * that we never cover with a buffer.  All of this is because
-	 * we are not actually going to write the extra blocks preallocated
-	 * at this point.
 	 *
 	 * We don't bother with this for sync writes, because we need
 	 * to minimize the amount we write for good performance.
 	 */
-	if (!(ioflag & PBF_SYNC) && ((offset + count) > XFS_SIZE(mp, io))) {
-		start_fsb = XFS_B_TO_FSBT(mp,
-				  ((xfs_ufsize_t)(offset + count - 1)));
-		count_fsb = mp->m_writeio_blocks;
-		while (count_fsb > 0) {
-			nimaps = XFS_WRITE_IMAPS;
-			error = XFS_BMAPI(mp, NULL, io, start_fsb, count_fsb,
-					  0, NULL, 0, imap, &nimaps,
-					  NULL);
-			if (error) {
-				return error;
-			}
-			for (n = 0; n < nimaps; n++) {
-				if ((imap[n].br_startblock != HOLESTARTBLOCK) &&
-				    (imap[n].br_startblock != DELAYSTARTBLOCK)) {
-					goto write_map;
-				}
-				start_fsb += imap[n].br_blockcount;
-				count_fsb -= imap[n].br_blockcount;
-				ASSERT(count_fsb < 0xffff000);
-			}
-		}
+	if (!(ioflag & PBF_SYNC) && ((offset + count) > ip->i_d.di_size)) {
+		xfs_off_t	aligned_offset;
+		unsigned int	iosize;
+		xfs_fileoff_t	ioalign;
+
 		iosize = mp->m_writeio_blocks;
 		aligned_offset = XFS_WRITEIO_ALIGN(mp, (offset + count - 1));
 		ioalign = XFS_B_TO_FSBT(mp, aligned_offset);
 		last_fsb = ioalign + iosize;
 		aeof = 1;
 	}
- write_map:
+
 	nimaps = XFS_WRITE_IMAPS;
 	firstblock = NULLFSBLOCK;
 
@@ -642,11 +458,11 @@ xfs_iomap_write_delay(
 	 * roundup the allocation request to m_dalign boundary if file size
 	 * is greater that 512K and we are allocating past the allocation eof
 	 */
-	if (mp->m_dalign && (XFS_SIZE(mp, io) >= mp->m_dalign) && aeof) {
+	if (mp->m_dalign && (isize >= mp->m_dalign) && aeof) {
 		int eof;
 		xfs_fileoff_t new_last_fsb;
 		new_last_fsb = roundup_64(last_fsb, mp->m_dalign);
-		error = XFS_BMAP_EOF(mp, io, new_last_fsb, XFS_DATA_FORK, &eof);
+		error = xfs_bmap_eof(ip, new_last_fsb, XFS_DATA_FORK, &eof);
 		if (error) {
 			return error;
 		}
@@ -655,7 +471,7 @@ xfs_iomap_write_delay(
 		}
 	}
 
-	error = XFS_BMAPI(mp, NULL, io, offset_fsb,
+	error = xfs_bmapi(NULL, ip, offset_fsb,
 			  (xfs_filblks_t)(last_fsb - offset_fsb),
 			  XFS_BMAPI_DELAY | XFS_BMAPI_WRITE |
 			  XFS_BMAPI_ENTIRE, &firstblock, 1, imap,
@@ -663,235 +479,257 @@ xfs_iomap_write_delay(
 	/*
 	 * This can be EDQUOT, if nimaps == 0
 	 */
-	if (error) {
+	if (error && (error != ENOSPC)) {
 		return XFS_ERROR(error);
 	}
 	/*
 	 * If bmapi returned us nothing, and if we didn't get back EDQUOT,
 	 * then we must have run out of space.
 	 */
+
 	if (nimaps == 0) {
-		return XFS_ERROR(ENOSPC);
+		if (xfs_flush_space(ip, &fsynced, &ioflag))
+			return XFS_ERROR(ENOSPC);
+
+		error = 0;
+		goto retry;
 	}
 
-	/*
-	 * Now map our desired I/O size and alignment over the
-	 * extents returned by xfs_bmapi().
-	 */
-	*npbmaps = _xfs_imap_to_bmap(io, offset, imap, pbmapp,
-						nimaps, *npbmaps);
+	*ret_imap = imap[0];
+	*nmaps = 1;
 	return 0;
 }
 
-STATIC int
-xfs_iomap_write_direct(
-	xfs_iocore_t	*io,
-	loff_t		offset,
-	size_t		count,
-	page_buf_bmap_t	*pbmapp,
-	int		*npbmaps,
-	int		ioflag,
-	int		found)
+
+/*
+ * Pass in a delayed allocate extent, convert it to real extents;
+ * return to the caller the extent we create which maps on top of
+ * the originating callers request.
+ *
+ * Called without a lock on the inode.
+ */
+int
+xfs_iomap_write_allocate(
+	xfs_inode_t	*ip,
+	xfs_bmbt_irec_t *map,
+	int		*retmap)
 {
-	xfs_inode_t	*ip = XFS_IO_INODE(io);
-	xfs_mount_t	*mp;
-	xfs_fileoff_t	offset_fsb;
-	xfs_fileoff_t	last_fsb;
+	xfs_mount_t	*mp = ip->i_mount;
+	xfs_fileoff_t	offset_fsb, last_block;
+	xfs_fileoff_t	end_fsb, map_start_fsb;
+	xfs_fsblock_t	first_block;
+	xfs_bmap_free_t	free_list;
 	xfs_filblks_t	count_fsb;
-	xfs_fsize_t	isize;
-	xfs_fsblock_t	firstfsb;
-	int		nimaps, maps;
-	int		error;
+	xfs_bmbt_irec_t	imap[XFS_STRAT_WRITE_IMAPS];
 	xfs_trans_t	*tp;
+	int		i, nimaps, committed;
+	int		error = 0;
 
-#define XFS_WRITE_IMAPS XFS_BMAP_MAX_NMAP
-	xfs_bmbt_irec_t imap[XFS_WRITE_IMAPS], *imapp;
-	xfs_bmap_free_t free_list;
-	int		aeof;
-	int		bmapi_flags;
-	xfs_filblks_t	datablocks;
-	int		rt;
-	int		committed;
-	int		numrtextents;
-	uint		resblks;
-	int		rtextsize;
+	*retmap = 0;
 
-	maps = min(XFS_WRITE_IMAPS, *npbmaps);
-	nimaps = maps;
+	/*
+	 * Make sure that the dquots are there.
+	 */
 
-	mp = io->io_mount;
-	isize = XFS_SIZE(mp, io);
-	if (io->io_new_size > isize)
-		isize = io->io_new_size;
+	if (XFS_IS_QUOTA_ON(mp) && XFS_NOT_DQATTACHED(mp, ip)) {
+		if ((error = xfs_qm_dqattach(ip, 0))) {
+			return XFS_ERROR(error);
+		}
+	}
 
-	aeof = ((offset + count) > isize) ? 1 : 0;
+	offset_fsb = map->br_startoff;
+	count_fsb = map->br_blockcount;
+	map_start_fsb = offset_fsb;
 
-	offset_fsb = XFS_B_TO_FSBT(mp, offset);
-	last_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)(offset + count)));
-	count_fsb = last_fsb - offset_fsb;
-	if (found && (pbmapp->pbm_flags & PBMF_HOLE)) {
-		xfs_fileoff_t	map_last_fsb;
+	XFS_STATS_ADD(xfsstats.xs_xstrat_bytes, XFS_FSB_TO_B(mp, count_fsb));
 
-		map_last_fsb = XFS_B_TO_FSB(mp,
-			(pbmapp->pbm_bsize + pbmapp->pbm_offset));
+	while (count_fsb != 0) {
+		/*
+		 * Set up a transaction with which to allocate the
+		 * backing store for the file.  Do allocations in a
+		 * loop until we get some space in the range we are
+		 * interested in.  The other space that might be allocated
+		 * is in the delayed allocation extent on which we sit
+		 * but before our buffer starts.
+		 */
 
-		if (map_last_fsb < last_fsb) {
-			last_fsb = map_last_fsb;
-			count_fsb = last_fsb - offset_fsb;
-		}
-		ASSERT(count_fsb > 0);
-	}
+		nimaps = 0;
+		while (nimaps == 0) {
+			tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
+			error = xfs_trans_reserve(tp, 0, XFS_WRITE_LOG_RES(mp),
+					0, XFS_TRANS_PERM_LOG_RES,
+					XFS_WRITE_LOG_COUNT);
+			if (error) {
+				xfs_trans_cancel(tp, 0);
+				return XFS_ERROR(error);
+			}
+			xfs_ilock(ip, XFS_ILOCK_EXCL);
+			xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
+			xfs_trans_ihold(tp, ip);
 
-	/*
-	 * roundup the allocation request to m_dalign boundary if file size
-	 * is greater that 512K and we are allocating past the allocation eof
-	 */
-	if (!found && mp->m_dalign && (isize >= 524288) && aeof) {
-		int		eof;
-		xfs_fileoff_t	new_last_fsb;
+			XFS_BMAP_INIT(&free_list, &first_block);
 
-		new_last_fsb = roundup_64(last_fsb, mp->m_dalign);
-		printk("xfs_iomap_write_direct: about to XFS_BMAP_EOF %Ld\n",
-			new_last_fsb);
-		error = XFS_BMAP_EOF(mp, io, new_last_fsb, XFS_DATA_FORK, &eof);
-		if (error)
-			goto error_out;
-		if (eof)
-			last_fsb = new_last_fsb;
-	}
+			nimaps = XFS_STRAT_WRITE_IMAPS;
+			/*
+			 * Ensure we don't go beyond eof - it is possible
+			 * the extents changed since we did the read call,
+			 * we dropped the ilock in the interim.
+			 */
 
-	bmapi_flags = XFS_BMAPI_WRITE|XFS_BMAPI_DIRECT_IO|XFS_BMAPI_ENTIRE;
-	bmapi_flags &= ~XFS_BMAPI_DIRECT_IO;
+			end_fsb = XFS_B_TO_FSB(mp, ip->i_d.di_size);
+			xfs_bmap_last_offset(NULL, ip, &last_block,
+				XFS_DATA_FORK);
+			last_block = XFS_FILEOFF_MAX(last_block, end_fsb);
+			if ((map_start_fsb + count_fsb) > last_block) {
+				count_fsb = last_block - map_start_fsb;
+				if (count_fsb == 0) {
+					error = EAGAIN;
+					goto trans_cancel;
+				}
+			}
 
-	/*
-	 * determine if this is a realtime file
-	 */
-	if ((rt = (ip->i_d.di_flags & XFS_DIFLAG_REALTIME)) != 0) {
-		rtextsize = mp->m_sb.sb_rextsize;
-	} else
-		rtextsize = 0;
+			/* Go get the actual blocks */
+			error = xfs_bmapi(tp, ip, map_start_fsb, count_fsb,
+					XFS_BMAPI_WRITE, &first_block, 1,
+					imap, &nimaps, &free_list);
 
-	error = 0;
+			if (error)
+				goto trans_cancel;
 
-	/*
-	 * allocate file space for the bmapp entries passed in.
-	 */
+			error = xfs_bmap_finish(&tp, &free_list,
+					first_block, &committed);
 
-	/*
-	 * determine if reserving space on
-	 * the data or realtime partition.
-	 */
-	if (rt) {
-		numrtextents = (count_fsb + rtextsize - 1);
-		do_div(numrtextents, rtextsize);
-		datablocks = 0;
-	} else {
-		datablocks = count_fsb;
-		numrtextents = 0;
-	}
+			if (error)
+				goto trans_cancel;
 
-	/*
-	 * allocate and setup the transaction
-	 */
-	tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
-	resblks = XFS_DIOSTRAT_SPACE_RES(mp, datablocks);
+			error = xfs_trans_commit(tp,
+					XFS_TRANS_RELEASE_LOG_RES, NULL);
 
-	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+			if (error)
+				goto error0;
 
-	error = xfs_trans_reserve(tp,
-				  resblks,
-				  XFS_WRITE_LOG_RES(mp),
-				  numrtextents,
-				  XFS_TRANS_PERM_LOG_RES,
-				  XFS_WRITE_LOG_COUNT);
+			xfs_iunlock(ip, XFS_ILOCK_EXCL);
+		}
 
-	/*
-	 * check for running out of space
-	 */
-	if (error) {
 		/*
-		 * Free the transaction structure.
+		 * See if we were able to allocate an extent that
+		 * covers at least part of the callers request
 		 */
-		xfs_trans_cancel(tp, 0);
-	}
 
-	xfs_ilock(ip, XFS_ILOCK_EXCL);
+		for (i = 0; i < nimaps; i++) {
+			if ((map->br_startoff >= imap[i].br_startoff) &&
+			    (map->br_startoff < (imap[i].br_startoff +
+					         imap[i].br_blockcount))) {
+				*map = imap[i];
+				*retmap = 1;
+				XFS_STATS_INC(xfsstats.xs_xstrat_quick);
+				return 0;
+			}
+			count_fsb -= imap[i].br_blockcount;
+		}
 
-	if (error)  {
-		goto error_out; /* Don't return in above if .. trans ..,
-					need lock to return */
+		/* So far we have not mapped the requested part of the
+		 * file, just surrounding data, try again.
+		 */
+		nimaps--;
+		offset_fsb = imap[nimaps].br_startoff +
+			     imap[nimaps].br_blockcount;
+		map_start_fsb = offset_fsb;
 	}
 
-	if (XFS_IS_QUOTA_ON(mp)) {
-		if (xfs_trans_reserve_quota(tp,
-					    ip->i_udquot,
-					    ip->i_gdquot,
-					    resblks, 0, 0)) {
-			error = (EDQUOT);
-			goto error1;
-		}
-		nimaps = 1;
-	} else {
-		nimaps = 2;
-	}
+trans_cancel:
+	xfs_bmap_cancel(&free_list);
+	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
+error0:
+	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+	return XFS_ERROR(error);
+}
 
-	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
-	xfs_trans_ihold(tp, ip);
+int
+xfs_iomap_write_unwritten(
+	xfs_inode_t	*ip,
+	loff_t		offset,
+	size_t		count)
+{
+	xfs_mount_t	*mp = ip->i_mount;
+	xfs_trans_t	*tp;
+	xfs_fileoff_t	offset_fsb;
+	xfs_filblks_t	count_fsb;
+	xfs_filblks_t	numblks_fsb;
+	xfs_bmbt_irec_t	imap;
+	int		committed;
+	int		error;
+	int		nres;
+	int		nimaps;
+	xfs_fsblock_t	firstfsb;
+	xfs_bmap_free_t	free_list;
 
-	/*
-	 * issue the bmapi() call to allocate the blocks
-	 */
-	XFS_BMAP_INIT(&free_list, &firstfsb);
-	imapp = &imap[0];
-	error = XFS_BMAPI(mp, tp, io, offset_fsb, count_fsb,
-		bmapi_flags, &firstfsb, 1, imapp, &nimaps, &free_list);
-	if (error) {
-		goto error0;
-	}
+	offset_fsb = XFS_B_TO_FSBT(mp, offset);
+	count_fsb = XFS_B_TO_FSB(mp, count);
 
-	/*
-	 * complete the transaction
-	 */
+	do {
+		nres = XFS_DIOSTRAT_SPACE_RES(mp, 0);
 
-	error = xfs_bmap_finish(&tp, &free_list, firstfsb, &committed);
-	if (error) {
-		goto error0;
-	}
+		/*
+		 * 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.
+		 */
 
-	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
-	if (error) {
-		goto error_out;
-	}
+		tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE);
+		error = xfs_trans_reserve(tp, nres,
+				XFS_WRITE_LOG_RES(mp), 0,
+				XFS_TRANS_PERM_LOG_RES,
+				XFS_WRITE_LOG_COUNT);
+		if (error) {
+			xfs_trans_cancel(tp, 0);
+			goto error0;
+		}
 
-	/* copy any maps to caller's array and return any error. */
-	if (nimaps == 0) {
-		error = (ENOSPC);
-		goto error_out;
-	}
+		xfs_ilock(ip, XFS_ILOCK_EXCL);
+		xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
+		xfs_trans_ihold(tp, ip);
 
-	maps = min(nimaps, maps);
-	*npbmaps = _xfs_imap_to_bmap(io, offset, &imap[0], pbmapp, maps,
-								*npbmaps);
-	if (*npbmaps) {
 		/*
-		 * this is new since xfs_iomap_read
-		 * didn't find it.
+		 * Modify the unwritten extent state of the buffer.
 		 */
-		if (*npbmaps != 1) {
-			/* NEED MORE WORK FOR MULTIPLE BMAPS (which are new) */
-			BUG();
-		}
-	}
-	goto out;
+		XFS_BMAP_INIT(&free_list, &firstfsb);
+		nimaps = 1;
+		error = xfs_bmapi(tp, ip, offset_fsb, count_fsb,
+				  XFS_BMAPI_WRITE, &firstfsb,
+				  1, &imap, &nimaps, &free_list);
+		if (error)
+			goto error_on_bmapi_transaction;
 
- error0:	/* Cancel bmap, unlock inode, and cancel trans */
-	xfs_bmap_cancel(&free_list);
+		error = xfs_bmap_finish(&(tp), &(free_list),
+				firstfsb, &committed);
+		if (error)
+			goto error_on_bmapi_transaction;
 
- error1:	/* Just cancel transaction */
-	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
-	*npbmaps = 0;	/* nothing set-up here */
+		error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
+		xfs_iunlock(ip, XFS_ILOCK_EXCL);
+		if (error)
+			goto error0;
 
-error_out:
-out:	/* Just return error and any tracing at end of routine */
+		if ((numblks_fsb = imap.br_blockcount) == 0) {
+			/*
+			 * The numblks_fsb value should always get
+			 * smaller, otherwise the loop is stuck.
+			 */
+			ASSERT(imap.br_blockcount);
+			break;
+		}
+		offset_fsb += numblks_fsb;
+		count_fsb -= numblks_fsb;
+	} while (count_fsb > 0);
+
+	return 0;
+
+error_on_bmapi_transaction:
+	xfs_bmap_cancel(&free_list);
+	xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT));
+	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+error0:
 	return XFS_ERROR(error);
 }
+

fs/xfs/linux/xfs_lrw.c

@@ -808,6 +808,25 @@ xfs_bdstrat_cb(struct xfs_buf *bp)
 	}
 }
 
+
+int
+xfs_bmap(bhv_desc_t	*bdp,
+	xfs_off_t	offset,
+	ssize_t		count,
+	int		flags,
+	page_buf_bmap_t	*pbmapp,
+	int		*npbmaps)
+{
+	xfs_inode_t	*ip = XFS_BHVTOI(bdp);
+	xfs_iocore_t	*io = &ip->i_iocore;
+
+	ASSERT((ip->i_d.di_mode & IFMT) == IFREG);
+	ASSERT(((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) != 0) ==
+	       ((ip->i_iocore.io_flags & XFS_IOCORE_RT) != 0));
+
+	return xfs_iomap(io, offset, count, flags, pbmapp, npbmaps);
+}
+
 /*
  * Wrapper around bdstrat so that we can stop data
  * from going to disk in case we are shutting down the filesystem.

fs/xfs/linux/xfs_lrw.h

@@ -36,6 +36,8 @@ struct vnode;
 struct bhv_desc;
 struct xfs_mount;
 struct xfs_iocore;
+struct xfs_inode;
+struct xfs_bmbt_irec;
 struct page_buf_s;
 struct page_buf_bmap_s;
 
@@ -62,6 +64,16 @@ extern ssize_t xfs_sendfile (struct bhv_desc *, struct file *,
 				loff_t *, size_t, read_actor_t,
 				void *, struct cred *);
 
+extern int xfs_iomap (struct xfs_iocore *, xfs_off_t, ssize_t, int,
+				struct page_buf_bmap_s *, int *);
+extern int xfs_iomap_write_direct (struct xfs_inode *, loff_t, size_t,
+				int, struct xfs_bmbt_irec *, int *, int);
+extern int xfs_iomap_write_delay (struct xfs_inode *, loff_t, size_t,
+				int, struct xfs_bmbt_irec *, int *);
+extern int xfs_iomap_write_allocate (struct xfs_inode *,
+				struct xfs_bmbt_irec *, int *);
+extern int xfs_iomap_write_unwritten (struct xfs_inode *, loff_t, size_t);
+
 extern int xfs_dev_is_read_only (struct xfs_mount *, char *);
 
 extern void XFS_log_write_unmount_ro (struct bhv_desc *);

fs/xfs/xfs_iocore.c

@@ -41,14 +41,24 @@ xfs_size_fn(
 }
 
 xfs_ioops_t	xfs_iocore_xfs = {
+	.xfs_ioinit		= (xfs_ioinit_t) fs_noerr,
 	.xfs_bmapi_func		= (xfs_bmapi_t) xfs_bmapi,
 	.xfs_bmap_eof_func	= (xfs_bmap_eof_t) xfs_bmap_eof,
+	.xfs_iomap_write_direct =
+			(xfs_iomap_write_direct_t) xfs_iomap_write_direct,
+	.xfs_iomap_write_delay =
+			(xfs_iomap_write_delay_t) xfs_iomap_write_delay,
+	.xfs_iomap_write_allocate =
+			(xfs_iomap_write_allocate_t) xfs_iomap_write_allocate,
+	.xfs_iomap_write_unwritten =
+			(xfs_iomap_write_unwritten_t) xfs_iomap_write_unwritten,
 	.xfs_ilock		= (xfs_lock_t) xfs_ilock,
+	.xfs_lck_map_shared	= (xfs_lck_map_shared_t) xfs_ilock_map_shared,
 	.xfs_ilock_demote	= (xfs_lock_demote_t) xfs_ilock_demote,
 	.xfs_ilock_nowait	= (xfs_lock_nowait_t) xfs_ilock_nowait,
 	.xfs_unlock		= (xfs_unlk_t) xfs_iunlock,
 	.xfs_size_func		= (xfs_size_t) xfs_size_fn,
-	.xfs_lastbyte		= (xfs_lastbyte_t) xfs_file_last_byte,
+	.xfs_iodone		= (xfs_iodone_t) fs_noerr,
 };
 
 void
@@ -83,4 +93,3 @@ xfs_iocore_inode_init(
 
 	xfs_iocore_inode_reinit(ip);
 }
-

fs/xfs/xfs_mount.h

@@ -87,41 +87,60 @@ struct xfs_bmap_free;
 #define AIL_LOCK(mp,s)		s=mutex_spinlock(&(mp)->m_ail_lock)
 #define AIL_UNLOCK(mp,s)	mutex_spinunlock(&(mp)->m_ail_lock, s)
 
-
-/* Prototypes and functions for I/O core modularization, a vector
- * of functions is used to indirect from xfs/cxfs independent code
- * to the xfs/cxfs dependent code.
- * The vector is placed in the mount structure so that we can
- * minimize the number of memory indirections involved.
+/*
+ * Prototypes and functions for I/O core modularization.
  */
+ 
+struct flid;
+struct buf;
 
+typedef int		(*xfs_ioinit_t)(struct vfs *,
+				struct xfs_mount_args *, int *);
 typedef int		(*xfs_bmapi_t)(struct xfs_trans *, void *,
 				xfs_fileoff_t, xfs_filblks_t, int,
 				xfs_fsblock_t *, xfs_extlen_t,
 				struct xfs_bmbt_irec *, int *,
 				struct xfs_bmap_free *);
 typedef int		(*xfs_bmap_eof_t)(void *, xfs_fileoff_t, int, int *);
+typedef int		(*xfs_iomap_write_direct_t)(
+				void *, loff_t, size_t, int,
+				struct xfs_bmbt_irec *, int *, int);
+typedef int		(*xfs_iomap_write_delay_t)(
+				void *, loff_t, size_t, int,
+				struct xfs_bmbt_irec *, int *);
+typedef int		(*xfs_iomap_write_allocate_t)(
+				void *, struct xfs_bmbt_irec *, int *);
+typedef int		(*xfs_iomap_write_unwritten_t)(
+				void *, loff_t, size_t);
+typedef uint		(*xfs_lck_map_shared_t)(void *);
 typedef void		(*xfs_lock_t)(void *, uint);
 typedef void		(*xfs_lock_demote_t)(void *, uint);
 typedef int		(*xfs_lock_nowait_t)(void *, uint);
 typedef void		(*xfs_unlk_t)(void *, unsigned int);
-typedef void		(*xfs_chgtime_t)(void *, int);
 typedef xfs_fsize_t	(*xfs_size_t)(void *);
-typedef xfs_fsize_t	(*xfs_lastbyte_t)(void *);
+typedef xfs_fsize_t	(*xfs_iodone_t)(struct vfs *);
 
 typedef struct xfs_ioops {
-	xfs_bmapi_t		xfs_bmapi_func;
-	xfs_bmap_eof_t		xfs_bmap_eof_func;
-	xfs_lock_t		xfs_ilock;
-	xfs_lock_demote_t	xfs_ilock_demote;
-	xfs_lock_nowait_t	xfs_ilock_nowait;
-	xfs_unlk_t		xfs_unlock;
-	xfs_chgtime_t		xfs_chgtime;
-	xfs_size_t		xfs_size_func;
-	xfs_lastbyte_t		xfs_lastbyte;
+	xfs_ioinit_t			xfs_ioinit;
+	xfs_bmapi_t			xfs_bmapi_func;
+	xfs_bmap_eof_t			xfs_bmap_eof_func;
+	xfs_iomap_write_direct_t	xfs_iomap_write_direct;
+	xfs_iomap_write_delay_t		xfs_iomap_write_delay;
+	xfs_iomap_write_allocate_t	xfs_iomap_write_allocate;
+	xfs_iomap_write_unwritten_t	xfs_iomap_write_unwritten;
+	xfs_lock_t			xfs_ilock;
+	xfs_lck_map_shared_t		xfs_lck_map_shared;
+	xfs_lock_demote_t		xfs_ilock_demote;
+	xfs_lock_nowait_t		xfs_ilock_nowait;
+	xfs_unlk_t			xfs_unlock;
+	xfs_size_t			xfs_size_func;
+	xfs_iodone_t			xfs_iodone;
 } xfs_ioops_t;
 
 
+#define XFS_IOINIT(vfsp, args, flags) \
+	(*(mp)->m_io_ops.xfs_ioinit)(vfsp, args, flags)
+
 #define XFS_BMAPI(mp, trans,io,bno,len,f,first,tot,mval,nmap,flist)	\
 	(*(mp)->m_io_ops.xfs_bmapi_func) \
 		(trans,(io)->io_obj,bno,len,f,first,tot,mval,nmap,flist)
@@ -130,9 +149,31 @@ typedef struct xfs_ioops {
 	(*(mp)->m_io_ops.xfs_bmap_eof_func) \
 		((io)->io_obj, endoff, whichfork, eof)
 
+#define XFS_IOMAP_WRITE_DIRECT(mp, io, offset, count, flags, mval, nmap, found)\
+	(*(mp)->m_io_ops.xfs_iomap_write_direct) \
+		((io)->io_obj, offset, count, flags, mval, nmap, found)
+
+#define XFS_IOMAP_WRITE_DELAY(mp, io, offset, count, flags, mval, nmap) \
+	(*(mp)->m_io_ops.xfs_iomap_write_delay) \
+		((io)->io_obj, offset, count, flags, mval, nmap)
+
+#define XFS_IOMAP_WRITE_ALLOCATE(mp, io, mval, nmap) \
+	(*(mp)->m_io_ops.xfs_iomap_write_allocate) \
+		((io)->io_obj, mval, nmap)
+
+#define XFS_IOMAP_WRITE_UNWRITTEN(mp, io, offset, count) \
+	(*(mp)->m_io_ops.xfs_iomap_write_unwritten) \
+		((io)->io_obj, offset, count)
+
+#define XFS_LCK_MAP_SHARED(mp, io) \
+	(*(mp)->m_io_ops.xfs_lck_map_shared)((io)->io_obj)
+
 #define XFS_ILOCK(mp, io, mode) \
 	(*(mp)->m_io_ops.xfs_ilock)((io)->io_obj, mode)
 
+#define XFS_ILOCK_NOWAIT(mp, io, mode) \
+	(*(mp)->m_io_ops.xfs_ilock_nowait)((io)->io_obj, mode)
+
 #define XFS_IUNLOCK(mp, io, mode) \
 	(*(mp)->m_io_ops.xfs_unlock)((io)->io_obj, mode)
 
@@ -142,8 +183,13 @@ typedef struct xfs_ioops {
 #define XFS_SIZE(mp, io) \
 	(*(mp)->m_io_ops.xfs_size_func)((io)->io_obj)
 
-#define XFS_LASTBYTE(mp, io) \
-	(*(mp)->m_io_ops.xfs_lastbyte)((io)->io_obj)
+#define XFS_IODONE(vfsp) \
+	(*(mp)->m_io_ops.xfs_iodone)(vfsp)
+
+
+/*
+ * Prototypes and functions for the XFS realtime subsystem.
+ */
 
 
 typedef struct xfs_mount {
@@ -303,8 +349,8 @@ typedef struct xfs_mount {
 /*
  * Default minimum read and write sizes.
  */
-#define XFS_READIO_LOG_LARGE	12
-#define XFS_WRITEIO_LOG_LARGE	12
+#define XFS_READIO_LOG_LARGE	16
+#define XFS_WRITEIO_LOG_LARGE	16
 /*
  * Default allocation size
  */