Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 2469 insertions, 0 deletions

diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
new file mode 100644
index 00000000000..2c37822d101
--- /dev/null
+++ b/fs/xfs/xfs_rtalloc.c
@@ -0,0 +1,2469 @@
+/*
+ * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like.  Any license provided herein, whether implied or
+ * otherwise, applies only to this software file.  Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA  94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+/*
+ * Free realtime space allocation for XFS.
+ */
+
+#include "xfs.h"
+#include "xfs_macros.h"
+#include "xfs_types.h"
+#include "xfs_inum.h"
+#include "xfs_log.h"
+#include "xfs_trans.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_dir.h"
+#include "xfs_dir2.h"
+#include "xfs_dmapi.h"
+#include "xfs_mount.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_ialloc_btree.h"
+#include "xfs_btree.h"
+#include "xfs_ialloc.h"
+#include "xfs_attr_sf.h"
+#include "xfs_dir_sf.h"
+#include "xfs_dir2_sf.h"
+#include "xfs_dinode.h"
+#include "xfs_inode.h"
+#include "xfs_alloc.h"
+#include "xfs_bmap.h"
+#include "xfs_bit.h"
+#include "xfs_rtalloc.h"
+#include "xfs_fsops.h"
+#include "xfs_error.h"
+#include "xfs_rw.h"
+#include "xfs_inode_item.h"
+#include "xfs_trans_space.h"
+
+
+/*
+ * Prototypes for internal functions.
+ */
+
+
+STATIC int xfs_rtallocate_range(xfs_mount_t *, xfs_trans_t *, xfs_rtblock_t,
+		xfs_extlen_t, xfs_buf_t **, xfs_fsblock_t *);
+STATIC int xfs_rtany_summary(xfs_mount_t *, xfs_trans_t *, int, int,
+		xfs_rtblock_t, xfs_buf_t **, xfs_fsblock_t *, int *);
+STATIC int xfs_rtcheck_range(xfs_mount_t *, xfs_trans_t *, xfs_rtblock_t,
+		xfs_extlen_t, int, xfs_rtblock_t *, int *);
+STATIC int xfs_rtfind_back(xfs_mount_t *, xfs_trans_t *, xfs_rtblock_t,
+		xfs_rtblock_t, xfs_rtblock_t *);
+STATIC int xfs_rtfind_forw(xfs_mount_t *, xfs_trans_t *, xfs_rtblock_t,
+		xfs_rtblock_t, xfs_rtblock_t *);
+STATIC int xfs_rtget_summary( xfs_mount_t *, xfs_trans_t *, int,
+		xfs_rtblock_t, xfs_buf_t **, xfs_fsblock_t *, xfs_suminfo_t *);
+STATIC int xfs_rtmodify_range(xfs_mount_t *, xfs_trans_t *, xfs_rtblock_t,
+		xfs_extlen_t, int);
+STATIC int xfs_rtmodify_summary(xfs_mount_t *, xfs_trans_t *, int,
+		xfs_rtblock_t, int, xfs_buf_t **, xfs_fsblock_t *);
+
+/*
+ * Internal functions.
+ */
+
+/*
+ * xfs_lowbit32: get low bit set out of 32-bit argument, -1 if none set.
+ */
+STATIC int
+xfs_lowbit32(
+	__uint32_t	v)
+{
+	if (v)
+		return ffs(v) - 1;
+	return -1;
+}
+
+/*
+ * Allocate space to the bitmap or summary file, and zero it, for growfs.
+ */
+STATIC int				/* error */
+xfs_growfs_rt_alloc(
+	xfs_mount_t	*mp,		/* file system mount point */
+	xfs_extlen_t	oblocks,	/* old count of blocks */
+	xfs_extlen_t	nblocks,	/* new count of blocks */
+	xfs_ino_t	ino)		/* inode number (bitmap/summary) */
+{
+	xfs_fileoff_t	bno;		/* block number in file */
+	xfs_buf_t	*bp;		/* temporary buffer for zeroing */
+	int		cancelflags;	/* flags for xfs_trans_cancel */
+	int		committed;	/* transaction committed flag */
+	xfs_daddr_t	d;		/* disk block address */
+	int		error;		/* error return value */
+	xfs_fsblock_t	firstblock;	/* first block allocated in xaction */
+	xfs_bmap_free_t	flist;		/* list of freed blocks */
+	xfs_fsblock_t	fsbno;		/* filesystem block for bno */
+	xfs_inode_t	*ip;		/* pointer to incore inode */
+	xfs_bmbt_irec_t	map;		/* block map output */
+	int		nmap;		/* number of block maps */
+	int		resblks;	/* space reservation */
+	xfs_trans_t	*tp;		/* transaction pointer */
+
+	/*
+	 * Allocate space to the file, as necessary.
+	 */
+	while (oblocks < nblocks) {
+		tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_ALLOC);
+		resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
+		cancelflags = 0;
+		/*
+		 * Reserve space & log for one extent added to the file.
+		 */
+		if ((error = xfs_trans_reserve(tp, resblks,
+				XFS_GROWRTALLOC_LOG_RES(mp), 0,
+				XFS_TRANS_PERM_LOG_RES,
+				XFS_DEFAULT_PERM_LOG_COUNT)))
+			goto error_exit;
+		cancelflags = XFS_TRANS_RELEASE_LOG_RES;
+		/*
+		 * Lock the inode.
+		 */
+		if ((error = xfs_trans_iget(mp, tp, ino, 0, XFS_ILOCK_EXCL, &ip)))
+			goto error_exit;
+		XFS_BMAP_INIT(&flist, &firstblock);
+		/*
+		 * Allocate blocks to the bitmap file.
+		 */
+		nmap = 1;
+		cancelflags |= XFS_TRANS_ABORT;
+		error = xfs_bmapi(tp, ip, oblocks, nblocks - oblocks,
+			XFS_BMAPI_WRITE | XFS_BMAPI_METADATA, &firstblock,
+			resblks, &map, &nmap, &flist);
+		if (!error && nmap < 1)
+			error = XFS_ERROR(ENOSPC);
+		if (error)
+			goto error_exit;
+		/*
+		 * Free any blocks freed up in the transaction, then commit.
+		 */
+		error = xfs_bmap_finish(&tp, &flist, firstblock, &committed);
+		if (error)
+			goto error_exit;
+		xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL);
+		/*
+		 * Now we need to clear the allocated blocks.
+		 * Do this one block per transaction, to keep it simple.
+		 */
+		cancelflags = 0;
+		for (bno = map.br_startoff, fsbno = map.br_startblock;
+		     bno < map.br_startoff + map.br_blockcount;
+		     bno++, fsbno++) {
+			tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_ZERO);
+			/*
+			 * Reserve log for one block zeroing.
+			 */
+			if ((error = xfs_trans_reserve(tp, 0,
+					XFS_GROWRTZERO_LOG_RES(mp), 0, 0, 0)))
+				goto error_exit;
+			/*
+			 * Lock the bitmap inode.
+			 */
+			if ((error = xfs_trans_iget(mp, tp, ino, 0, XFS_ILOCK_EXCL,
+					&ip)))
+				goto error_exit;
+			/*
+			 * Get a buffer for the block.
+			 */
+			d = XFS_FSB_TO_DADDR(mp, fsbno);
+			bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
+				mp->m_bsize, 0);
+			if (bp == NULL) {
+				error = XFS_ERROR(EIO);
+				goto error_exit;
+			}
+			memset(XFS_BUF_PTR(bp), 0, mp->m_sb.sb_blocksize);
+			xfs_trans_log_buf(tp, bp, 0, mp->m_sb.sb_blocksize - 1);
+			/*
+			 * Commit the transaction.
+			 */
+			xfs_trans_commit(tp, 0, NULL);
+		}
+		/*
+		 * Go on to the next extent, if any.
+		 */
+		oblocks = map.br_startoff + map.br_blockcount;
+	}
+	return 0;
+error_exit:
+	xfs_trans_cancel(tp, cancelflags);
+	return error;
+}
+
+/*
+ * Attempt to allocate an extent minlen<=len<=maxlen starting from
+ * bitmap block bbno.  If we don't get maxlen then use prod to trim
+ * the length, if given.  Returns error; returns starting block in *rtblock.
+ * The lengths are all in rtextents.
+ */
+STATIC int				/* error */
+xfs_rtallocate_extent_block(
+	xfs_mount_t	*mp,		/* file system mount point */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	xfs_rtblock_t	bbno,		/* bitmap block number */
+	xfs_extlen_t	minlen,		/* minimum length to allocate */
+	xfs_extlen_t	maxlen,		/* maximum length to allocate */
+	xfs_extlen_t	*len,		/* out: actual length allocated */
+	xfs_rtblock_t	*nextp,		/* out: next block to try */
+	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
+	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
+	xfs_extlen_t	prod,		/* extent product factor */
+	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
+{
+	xfs_rtblock_t	besti;		/* best rtblock found so far */
+	xfs_rtblock_t	bestlen;	/* best length found so far */
+	xfs_rtblock_t	end;		/* last rtblock in chunk */
+	int		error;		/* error value */
+	xfs_rtblock_t	i;		/* current rtblock trying */
+	xfs_rtblock_t	next;		/* next rtblock to try */
+	int		stat;		/* status from internal calls */
+
+	/*
+	 * Loop over all the extents starting in this bitmap block,
+	 * looking for one that's long enough.
+	 */
+	for (i = XFS_BLOCKTOBIT(mp, bbno), besti = -1, bestlen = 0,
+		end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1;
+	     i <= end;
+	     i++) {
+		/*
+		 * See if there's a free extent of maxlen starting at i.
+		 * If it's not so then next will contain the first non-free.
+		 */
+		error = xfs_rtcheck_range(mp, tp, i, maxlen, 1, &next, &stat);
+		if (error) {
+			return error;
+		}
+		if (stat) {
+			/*
+			 * i for maxlen is all free, allocate and return that.
+			 */
+			error = xfs_rtallocate_range(mp, tp, i, maxlen, rbpp,
+				rsb);
+			if (error) {
+				return error;
+			}
+			*len = maxlen;
+			*rtblock = i;
+			return 0;
+		}
+		/*
+		 * In the case where we have a variable-sized allocation
+		 * request, figure out how big this free piece is,
+		 * and if it's big enough for the minimum, and the best
+		 * so far, remember it.
+		 */
+		if (minlen < maxlen) {
+			xfs_rtblock_t	thislen;	/* this extent size */
+
+			thislen = next - i;
+			if (thislen >= minlen && thislen > bestlen) {
+				besti = i;
+				bestlen = thislen;
+			}
+		}
+		/*
+		 * If not done yet, find the start of the next free space.
+		 */
+		if (next < end) {
+			error = xfs_rtfind_forw(mp, tp, next, end, &i);
+			if (error) {
+				return error;
+			}
+		} else
+			break;
+	}
+	/*
+	 * Searched the whole thing & didn't find a maxlen free extent.
+	 */
+	if (minlen < maxlen && besti != -1) {
+		xfs_extlen_t	p;	/* amount to trim length by */
+
+		/*
+		 * If size should be a multiple of prod, make that so.
+		 */
+		if (prod > 1 && (p = do_mod(bestlen, prod)))
+			bestlen -= p;
+		/*
+		 * Allocate besti for bestlen & return that.
+		 */
+		error = xfs_rtallocate_range(mp, tp, besti, bestlen, rbpp, rsb);
+		if (error) {
+			return error;
+		}
+		*len = bestlen;
+		*rtblock = besti;
+		return 0;
+	}
+	/*
+	 * Allocation failed.  Set *nextp to the next block to try.
+	 */
+	*nextp = next;
+	*rtblock = NULLRTBLOCK;
+	return 0;
+}
+
+/*
+ * Allocate an extent of length minlen<=len<=maxlen, starting at block
+ * bno.  If we don't get maxlen then use prod to trim the length, if given.
+ * Returns error; returns starting block in *rtblock.
+ * The lengths are all in rtextents.
+ */
+STATIC int				/* error */
+xfs_rtallocate_extent_exact(
+	xfs_mount_t	*mp,		/* file system mount point */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	xfs_rtblock_t	bno,		/* starting block number to allocate */
+	xfs_extlen_t	minlen,		/* minimum length to allocate */
+	xfs_extlen_t	maxlen,		/* maximum length to allocate */
+	xfs_extlen_t	*len,		/* out: actual length allocated */
+	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
+	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
+	xfs_extlen_t	prod,		/* extent product factor */
+	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
+{
+	int		error;		/* error value */
+	xfs_extlen_t	i;		/* extent length trimmed due to prod */
+	int		isfree;		/* extent is free */
+	xfs_rtblock_t	next;		/* next block to try (dummy) */
+
+	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
+	/*
+	 * Check if the range in question (for maxlen) is free.
+	 */
+	error = xfs_rtcheck_range(mp, tp, bno, maxlen, 1, &next, &isfree);
+	if (error) {
+		return error;
+	}
+	if (isfree) {
+		/*
+		 * If it is, allocate it and return success.
+		 */
+		error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
+		if (error) {
+			return error;
+		}
+		*len = maxlen;
+		*rtblock = bno;
+		return 0;
+	}
+	/*
+	 * If not, allocate what there is, if it's at least minlen.
+	 */
+	maxlen = next - bno;
+	if (maxlen < minlen) {
+		/*
+		 * Failed, return failure status.
+		 */
+		*rtblock = NULLRTBLOCK;
+		return 0;
+	}
+	/*
+	 * Trim off tail of extent, if prod is specified.
+	 */
+	if (prod > 1 && (i = maxlen % prod)) {
+		maxlen -= i;
+		if (maxlen < minlen) {
+			/*
+			 * Now we can't do it, return failure status.
+			 */
+			*rtblock = NULLRTBLOCK;
+			return 0;
+		}
+	}
+	/*
+	 * Allocate what we can and return it.
+	 */
+	error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
+	if (error) {
+		return error;
+	}
+	*len = maxlen;
+	*rtblock = bno;
+	return 0;
+}
+
+/*
+ * Allocate an extent of length minlen<=len<=maxlen, starting as near
+ * to bno as possible.  If we don't get maxlen then use prod to trim
+ * the length, if given.  The lengths are all in rtextents.
+ */
+STATIC int				/* error */
+xfs_rtallocate_extent_near(
+	xfs_mount_t	*mp,		/* file system mount point */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	xfs_rtblock_t	bno,		/* starting block number to allocate */
+	xfs_extlen_t	minlen,		/* minimum length to allocate */
+	xfs_extlen_t	maxlen,		/* maximum length to allocate */
+	xfs_extlen_t	*len,		/* out: actual length allocated */
+	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
+	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
+	xfs_extlen_t	prod,		/* extent product factor */
+	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
+{
+	int		any;		/* any useful extents from summary */
+	xfs_rtblock_t	bbno;		/* bitmap block number */
+	int		error;		/* error value */
+	int		i;		/* bitmap block offset (loop control) */
+	int		j;		/* secondary loop control */
+	int		log2len;	/* log2 of minlen */
+	xfs_rtblock_t	n;		/* next block to try */
+	xfs_rtblock_t	r;		/* result block */
+
+	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
+	/*
+	 * If the block number given is off the end, silently set it to
+	 * the last block.
+	 */
+	if (bno >= mp->m_sb.sb_rextents)
+		bno = mp->m_sb.sb_rextents - 1;
+	/*
+	 * Try the exact allocation first.
+	 */
+	error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen, len,
+		rbpp, rsb, prod, &r);
+	if (error) {
+		return error;
+	}
+	/*
+	 * If the exact allocation worked, return that.
+	 */
+	if (r != NULLRTBLOCK) {
+		*rtblock = r;
+		return 0;
+	}
+	bbno = XFS_BITTOBLOCK(mp, bno);
+	i = 0;
+	log2len = xfs_highbit32(minlen);
+	/*
+	 * Loop over all bitmap blocks (bbno + i is current block).
+	 */
+	for (;;) {
+		/*
+		 * Get summary information of extents of all useful levels
+		 * starting in this bitmap block.
+		 */
+		error = xfs_rtany_summary(mp, tp, log2len, mp->m_rsumlevels - 1,
+			bbno + i, rbpp, rsb, &any);
+		if (error) {
+			return error;
+		}
+		/*
+		 * If there are any useful extents starting here, try
+		 * allocating one.
+		 */
+		if (any) {
+			/*
+			 * On the positive side of the starting location.
+			 */
+			if (i >= 0) {
+				/*
+				 * Try to allocate an extent starting in
+				 * this block.
+				 */
+				error = xfs_rtallocate_extent_block(mp, tp,
+					bbno + i, minlen, maxlen, len, &n, rbpp,
+					rsb, prod, &r);
+				if (error) {
+					return error;
+				}
+				/*
+				 * If it worked, return it.
+				 */
+				if (r != NULLRTBLOCK) {
+					*rtblock = r;
+					return 0;
+				}
+			}
+			/*
+			 * On the negative side of the starting location.
+			 */
+			else {		/* i < 0 */
+				/*
+				 * Loop backwards through the bitmap blocks from
+				 * the starting point-1 up to where we are now.
+				 * There should be an extent which ends in this
+				 * bitmap block and is long enough.
+				 */
+				for (j = -1; j > i; j--) {
+					/*
+					 * Grab the summary information for
+					 * this bitmap block.
+					 */
+					error = xfs_rtany_summary(mp, tp,
+						log2len, mp->m_rsumlevels - 1,
+						bbno + j, rbpp, rsb, &any);
+					if (error) {
+						return error;
+					}
+					/*
+					 * If there's no extent given in the
+					 * summary that means the extent we
+					 * found must carry over from an
+					 * earlier block.  If there is an
+					 * extent given, we've already tried
+					 * that allocation, don't do it again.
+					 */
+					if (any)
+						continue;
+					error = xfs_rtallocate_extent_block(mp,
+						tp, bbno + j, minlen, maxlen,
+						len, &n, rbpp, rsb, prod, &r);
+					if (error) {
+						return error;
+					}
+					/*
+					 * If it works, return the extent.
+					 */
+					if (r != NULLRTBLOCK) {
+						*rtblock = r;
+						return 0;
+					}
+				}
+				/*
+				 * There weren't intervening bitmap blocks
+				 * with a long enough extent, or the
+				 * allocation didn't work for some reason
+				 * (i.e. it's a little * too short).
+				 * Try to allocate from the summary block
+				 * that we found.
+				 */
+				error = xfs_rtallocate_extent_block(mp, tp,
+					bbno + i, minlen, maxlen, len, &n, rbpp,
+					rsb, prod, &r);
+				if (error) {
+					return error;
+				}
+				/*
+				 * If it works, return the extent.
+				 */
+				if (r != NULLRTBLOCK) {
+					*rtblock = r;
+					return 0;
+				}
+			}
+		}
+		/*
+		 * Loop control.  If we were on the positive side, and there's
+		 * still more blocks on the negative side, go there.
+		 */
+		if (i > 0 && (int)bbno - i >= 0)
+			i = -i;
+		/*
+		 * If positive, and no more negative, but there are more
+		 * positive, go there.
+		 */
+		else if (i > 0 && (int)bbno + i < mp->m_sb.sb_rbmblocks - 1)
+			i++;
+		/*
+		 * If negative or 0 (just started), and there are positive
+		 * blocks to go, go there.  The 0 case moves to block 1.
+		 */
+		else if (i <= 0 && (int)bbno - i < mp->m_sb.sb_rbmblocks - 1)
+			i = 1 - i;
+		/*
+		 * If negative or 0 and there are more negative blocks,
+		 * go there.
+		 */
+		else if (i <= 0 && (int)bbno + i > 0)
+			i--;
+		/*
+		 * Must be done.  Return failure.
+		 */
+		else
+			break;
+	}
+	*rtblock = NULLRTBLOCK;
+	return 0;
+}
+
+/*
+ * Allocate an extent of length minlen<=len<=maxlen, with no position
+ * specified.  If we don't get maxlen then use prod to trim
+ * the length, if given.  The lengths are all in rtextents.
+ */
+STATIC int				/* error */
+xfs_rtallocate_extent_size(
+	xfs_mount_t	*mp,		/* file system mount point */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	xfs_extlen_t	minlen,		/* minimum length to allocate */
+	xfs_extlen_t	maxlen,		/* maximum length to allocate */
+	xfs_extlen_t	*len,		/* out: actual length allocated */
+	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
+	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
+	xfs_extlen_t	prod,		/* extent product factor */
+	xfs_rtblock_t	*rtblock)	/* out: start block allocated */
+{
+	int		error;		/* error value */
+	int		i;		/* bitmap block number */
+	int		l;		/* level number (loop control) */
+	xfs_rtblock_t	n;		/* next block to be tried */
+	xfs_rtblock_t	r;		/* result block number */
+	xfs_suminfo_t	sum;		/* summary information for extents */
+
+	ASSERT(minlen % prod == 0 && maxlen % prod == 0);
+	/*
+	 * Loop over all the levels starting with maxlen.
+	 * At each level, look at all the bitmap blocks, to see if there
+	 * are extents starting there that are long enough (>= maxlen).
+	 * Note, only on the initial level can the allocation fail if
+	 * the summary says there's an extent.
+	 */
+	for (l = xfs_highbit32(maxlen); l < mp->m_rsumlevels; l++) {
+		/*
+		 * Loop over all the bitmap blocks.
+		 */
+		for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
+			/*
+			 * Get the summary for this level/block.
+			 */
+			error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
+				&sum);
+			if (error) {
+				return error;
+			}
+			/*
+			 * Nothing there, on to the next block.
+			 */
+			if (!sum)
+				continue;
+			/*
+			 * Try allocating the extent.
+			 */
+			error = xfs_rtallocate_extent_block(mp, tp, i, maxlen,
+				maxlen, len, &n, rbpp, rsb, prod, &r);
+			if (error) {
+				return error;
+			}
+			/*
+			 * If it worked, return that.
+			 */
+			if (r != NULLRTBLOCK) {
+				*rtblock = r;
+				return 0;
+			}
+			/*
+			 * If the "next block to try" returned from the
+			 * allocator is beyond the next bitmap block,
+			 * skip to that bitmap block.
+			 */
+			if (XFS_BITTOBLOCK(mp, n) > i + 1)
+				i = XFS_BITTOBLOCK(mp, n) - 1;
+		}
+	}
+	/*
+	 * Didn't find any maxlen blocks.  Try smaller ones, unless
+	 * we're asking for a fixed size extent.
+	 */
+	if (minlen > --maxlen) {
+		*rtblock = NULLRTBLOCK;
+		return 0;
+	}
+	/*
+	 * Loop over sizes, from maxlen down to minlen.
+	 * This time, when we do the allocations, allow smaller ones
+	 * to succeed.
+	 */
+	for (l = xfs_highbit32(maxlen); l >= xfs_highbit32(minlen); l--) {
+		/*
+		 * Loop over all the bitmap blocks, try an allocation
+		 * starting in that block.
+		 */
+		for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
+			/*
+			 * Get the summary information for this level/block.
+			 */
+			error =	xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
+						  &sum);
+			if (error) {
+				return error;
+			}
+			/*
+			 * If nothing there, go on to next.
+			 */
+			if (!sum)
+				continue;
+			/*
+			 * Try the allocation.  Make sure the specified
+			 * minlen/maxlen are in the possible range for
+			 * this summary level.
+			 */
+			error = xfs_rtallocate_extent_block(mp, tp, i,
+					XFS_RTMAX(minlen, 1 << l),
+					XFS_RTMIN(maxlen, (1 << (l + 1)) - 1),
+					len, &n, rbpp, rsb, prod, &r);
+			if (error) {
+				return error;
+			}
+			/*
+			 * If it worked, return that extent.
+			 */
+			if (r != NULLRTBLOCK) {
+				*rtblock = r;
+				return 0;
+			}
+			/*
+			 * If the "next block to try" returned from the
+			 * allocator is beyond the next bitmap block,
+			 * skip to that bitmap block.
+			 */
+			if (XFS_BITTOBLOCK(mp, n) > i + 1)
+				i = XFS_BITTOBLOCK(mp, n) - 1;
+		}
+	}
+	/*
+	 * Got nothing, return failure.
+	 */
+	*rtblock = NULLRTBLOCK;
+	return 0;
+}
+
+/*
+ * Mark an extent specified by start and len allocated.
+ * Updates all the summary information as well as the bitmap.
+ */
+STATIC int				/* error */
+xfs_rtallocate_range(
+	xfs_mount_t	*mp,		/* file system mount point */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	xfs_rtblock_t	start,		/* start block to allocate */
+	xfs_extlen_t	len,		/* length to allocate */
+	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
+	xfs_fsblock_t	*rsb)		/* in/out: summary block number */
+{
+	xfs_rtblock_t	end;		/* end of the allocated extent */
+	int		error;		/* error value */
+	xfs_rtblock_t	postblock;	/* first block allocated > end */
+	xfs_rtblock_t	preblock;	/* first block allocated < start */
+
+	end = start + len - 1;
+	/*
+	 * Assume we're allocating out of the middle of a free extent.
+	 * We need to find the beginning and end of the extent so we can
+	 * properly update the summary.
+	 */
+	error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
+	if (error) {
+		return error;
+	}
+	/*
+	 * Find the next allocated block (end of free extent).
+	 */
+	error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
+		&postblock);
+	if (error) {
+		return error;
+	}
+	/*
+	 * Decrement the summary information corresponding to the entire
+	 * (old) free extent.
+	 */
+	error = xfs_rtmodify_summary(mp, tp,
+		XFS_RTBLOCKLOG(postblock + 1 - preblock),
+		XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
+	if (error) {
+		return error;
+	}
+	/*
+	 * If there are blocks not being allocated at the front of the
+	 * old extent, add summary data for them to be free.
+	 */
+	if (preblock < start) {
+		error = xfs_rtmodify_summary(mp, tp,
+			XFS_RTBLOCKLOG(start - preblock),
+			XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
+		if (error) {
+			return error;
+		}
+	}
+	/*
+	 * If there are blocks not being allocated at the end of the
+	 * old extent, add summary data for them to be free.
+	 */
+	if (postblock > end) {
+		error = xfs_rtmodify_summary(mp, tp,
+			XFS_RTBLOCKLOG(postblock - end),
+			XFS_BITTOBLOCK(mp, end + 1), 1, rbpp, rsb);
+		if (error) {
+			return error;
+		}
+	}
+	/*
+	 * Modify the bitmap to mark this extent allocated.
+	 */
+	error = xfs_rtmodify_range(mp, tp, start, len, 0);
+	return error;
+}
+
+/*
+ * Return whether there are any free extents in the size range given
+ * by low and high, for the bitmap block bbno.
+ */
+STATIC int				/* error */
+xfs_rtany_summary(
+	xfs_mount_t	*mp,		/* file system mount structure */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	int		low,		/* low log2 extent size */
+	int		high,		/* high log2 extent size */
+	xfs_rtblock_t	bbno,		/* bitmap block number */
+	xfs_buf_t	**rbpp,		/* in/out: summary block buffer */
+	xfs_fsblock_t	*rsb,		/* in/out: summary block number */
+	int		*stat)		/* out: any good extents here? */
+{
+	int		error;		/* error value */
+	int		log;		/* loop counter, log2 of ext. size */
+	xfs_suminfo_t	sum;		/* summary data */
+
+	/*
+	 * Loop over logs of extent sizes.  Order is irrelevant.
+	 */
+	for (log = low; log <= high; log++) {
+		/*
+		 * Get one summary datum.
+		 */
+		error = xfs_rtget_summary(mp, tp, log, bbno, rbpp, rsb, &sum);
+		if (error) {
+			return error;
+		}
+		/*
+		 * If there are any, return success.
+		 */
+		if (sum) {
+			*stat = 1;
+			return 0;
+		}
+	}
+	/*
+	 * Found nothing, return failure.
+	 */
+	*stat = 0;
+	return 0;
+}
+
+/*
+ * Get a buffer for the bitmap or summary file block specified.
+ * The buffer is returned read and locked.
+ */
+STATIC int				/* error */
+xfs_rtbuf_get(
+	xfs_mount_t	*mp,		/* file system mount structure */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	xfs_rtblock_t	block,		/* block number in bitmap or summary */
+	int		issum,		/* is summary not bitmap */
+	xfs_buf_t	**bpp)		/* output: buffer for the block */
+{
+	xfs_buf_t	*bp;		/* block buffer, result */
+	xfs_daddr_t	d;		/* disk addr of block */
+	int		error;		/* error value */
+	xfs_fsblock_t	fsb;		/* fs block number for block */
+	xfs_inode_t	*ip;		/* bitmap or summary inode */
+
+	ip = issum ? mp->m_rsumip : mp->m_rbmip;
+	/*
+	 * Map from the file offset (block) and inode number to the
+	 * file system block.
+	 */
+	error = xfs_bmapi_single(tp, ip, XFS_DATA_FORK, &fsb, block);
+	if (error) {
+		return error;
+	}
+	ASSERT(fsb != NULLFSBLOCK);
+	/*
+	 * Convert to disk address for buffer cache.
+	 */
+	d = XFS_FSB_TO_DADDR(mp, fsb);
+	/*
+	 * Read the buffer.
+	 */
+	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d,
+				   mp->m_bsize, 0, &bp);
+	if (error) {
+		return error;
+	}
+	ASSERT(bp && !XFS_BUF_GETERROR(bp));
+	*bpp = bp;
+	return 0;
+}
+
+#ifdef DEBUG
+/*
+ * Check that the given extent (block range) is allocated already.
+ */
+STATIC int				/* error */
+xfs_rtcheck_alloc_range(
+	xfs_mount_t	*mp,		/* file system mount point */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	xfs_rtblock_t	bno,		/* starting block number of extent */
+	xfs_extlen_t	len,		/* length of extent */
+	int		*stat)		/* out: 1 for allocated, 0 for not */
+{
+	xfs_rtblock_t	new;		/* dummy for xfs_rtcheck_range */
+
+	return xfs_rtcheck_range(mp, tp, bno, len, 0, &new, stat);
+}
+#endif
+
+#ifdef DEBUG
+/*
+ * Check whether the given block in the bitmap has the given value.
+ */
+STATIC int				/* 1 for matches, 0 for not */
+xfs_rtcheck_bit(
+	xfs_mount_t	*mp,		/* file system mount structure */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	xfs_rtblock_t	start,		/* bit (block) to check */
+	int		val)		/* 1 for free, 0 for allocated */
+{
+	int		bit;		/* bit number in the word */
+	xfs_rtblock_t	block;		/* bitmap block number */
+	xfs_buf_t	*bp;		/* buf for the block */
+	xfs_rtword_t	*bufp;		/* pointer into the buffer */
+	/* REFERENCED */
+	int		error;		/* error value */
+	xfs_rtword_t	wdiff;		/* difference between bit & expected */
+	int		word;		/* word number in the buffer */
+	xfs_rtword_t	wval;		/* word value from buffer */
+
+	block = XFS_BITTOBLOCK(mp, start);
+	error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
+	bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
+	word = XFS_BITTOWORD(mp, start);
+	bit = (int)(start & (XFS_NBWORD - 1));
+	wval = bufp[word];
+	xfs_trans_brelse(tp, bp);
+	wdiff = (wval ^ -val) & ((xfs_rtword_t)1 << bit);
+	return !wdiff;
+}
+#endif	/* DEBUG */
+
+#if 0
+/*
+ * Check that the given extent (block range) is free already.
+ */
+STATIC int				/* error */
+xfs_rtcheck_free_range(
+	xfs_mount_t	*mp,		/* file system mount point */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	xfs_rtblock_t	bno,		/* starting block number of extent */
+	xfs_extlen_t	len,		/* length of extent */
+	int		*stat)		/* out: 1 for free, 0 for not */
+{
+	xfs_rtblock_t	new;		/* dummy for xfs_rtcheck_range */
+
+	return xfs_rtcheck_range(mp, tp, bno, len, 1, &new, stat);
+}
+#endif
+
+/*
+ * Check that the given range is either all allocated (val = 0) or
+ * all free (val = 1).
+ */
+STATIC int				/* error */
+xfs_rtcheck_range(
+	xfs_mount_t	*mp,		/* file system mount point */
+	xfs_trans_t	*tp,		/* transaction pointer */
+	xfs_rtblock_t	start,		/* starting block number of extent */
+	xfs_extlen_t	len,		/* length of extent */
+	int		val,		/* 1 for free, 0 for allocated */
+	xfs_rtblock_t	*new,		/* out: first block not matching */
+	int		*stat)		/* out: 1 for matches, 0 for not */
+{
+	xfs_rtword_t	*b;		/* current word in buffer */
+	int		bit;		/* bit number in the word */
+	xfs_rtblock_t	block;		/* bitmap block number */
+	xfs_buf_t	*bp;		/* buf for the block */
+	xfs_rtword_t	*bufp;		/* starting word in buffer */
+	int		error;		/* error value */
+	xfs_rtblock_t	i;		/* current bit number rel. to start */
+	xfs_rtblock_t	lastbit;	/* last useful bit in word */
+	xfs_rtword_t	mask;		/* mask of relevant bits for value */
+	xfs_rtword_t	wdiff;		/* difference from wanted value */
+	int		word;		/* word number in the buffer */
+
+	/*
+	 * Compute starting bitmap block number
+	 */
+	block = XFS_BITTOBLOCK(mp, start);
+	/*
+	 * Read the bitmap block.
+	 */
+	error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
+	if (error) {
+		return error;
+	}
+	bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
+	/*
+	 * Compute the starting word's address, and starting bit.
+	 */
+	word = XFS_BITTOWORD(mp, start);
+	b = &bufp[word];
+	bit = (int)(start & (XFS_NBWORD - 1));
+	/*
+	 * 0 (allocated) => all zero's; 1 (free) => all one's.
+	 */
+	val = -val;
+	/*
+	 * If not starting on a word boundary, deal with the first
+	 * (partial) word.
+	 */
+	if (bit) {
+		/*
+		 * Compute first bit not examined.
+		 */
+		lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
+		/*
+		 * Mask of relevant bits.
+		 */
+		mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
+		/*
+		 * Compute difference between actual and desired value.
+		 */
+		if ((wdiff = (*b ^ val) & mask)) {
+			/*
+			 * Different, compute first wrong bit and return.
+			 */
+			xfs_trans_brelse(tp, bp);
+			i = XFS_RTLOBIT(wdiff) - bit;
+			*new = start + i;
+			*stat = 0;
+			return 0;
+		}
+		i = lastbit - bit;
+		/*
+		 * Go on to next block if that's where the next word is
+		 * and we need the next word.
+		 */
+		if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
+			/*
+			 * If done with this block, get the next one.
+			 */
+			xfs_trans_brelse(tp, bp);
+			error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
+			if (error) {
+				return error;
+			}
+			b = bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
+			word = 0;
+		} else {
+			/*
+			 * Go on to the next word in the buffer.
+			 */
+			b++;
+		}
+	} else {
+		/*
+		 * Starting on a word boundary, no partial word.
+		 */
+		i = 0;
+	}
+	/*
+	 * Loop over whole words in buffers.  When we use up one buffer
+	 * we move on to the next one.
+	 */
+	while (len - i >= XFS_NBWORD) {
+		/*
+		 * Compute difference between actual and desired value.
+		 */
+		if ((wdiff = *b ^ val)) {
+			/*
+			 * Different, compute first wrong bit and return.
+			 */
+			xfs_trans_brelse(tp, bp);
+			i += XFS_RTLOBIT(wdiff);
+			*new = start + i;
+			*stat = 0;
+			return 0;
+		}
+		i += XFS_NBWORD;
+		/*
+		 * Go on to next block if that's where the next word is
+		 * and we need the next word.
+		 */
+		if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
+			/*
+			 * If done with this block, get the next one.
+			 */
+			xfs_trans_brelse(tp, bp);
+			error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
+			if (error) {
+				return error;
+			}
+			b = bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
+			word = 0;
+		} else {
+			/*
+			 * Go on to the next word in the buffer.
+			 */
+			b++;
+		}
+	}
+	/*
+	 * If not ending on a word boundary, deal with the last
+	 * (partial) word.
+	 */
+	if ((lastbit = len - i)) {
+		/*
+		 * Mask of relevant bits.
+		 */
+		mask = ((xfs_rtword_t)1 << lastbit) - 1;
+		/*
+		 * Compute difference between actual and desired value.
+		 */
+		if ((wdiff = (*b ^ val) & mask)) {
+			/*
+			 * Different, compute first wrong bit and return.
+			 */
+			xfs_trans_brelse(tp, bp);
+			i += XFS_RTLOBIT(wdiff);
+			*new = start + i;
+			*stat = 0;
+			return 0;
+		} else
+			i = len;