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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/xfs/xfs_rtalloc.c
downloadop-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
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!
Diffstat (limited to 'fs/xfs/xfs_rtalloc.c')
-rw-r--r--fs/xfs/xfs_rtalloc.c2469
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 0000000..2c37822
--- /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;
+ }
+ /*
+ * Successful, return.
+ */
+ xfs_trans_brelse(tp, bp);
+ *new = start + i;
+ *stat = 1;
+ return 0;
+}
+
+/*
+ * Copy and transform the summary file, given the old and new
+ * parameters in the mount structures.
+ */
+STATIC int /* error */
+xfs_rtcopy_summary(
+ xfs_mount_t *omp, /* old file system mount point */
+ xfs_mount_t *nmp, /* new file system mount point */
+ xfs_trans_t *tp) /* transaction pointer */
+{
+ xfs_rtblock_t bbno; /* bitmap block number */
+ xfs_buf_t *bp; /* summary buffer */
+ int error; /* error return value */
+ int log; /* summary level number (log length) */
+ xfs_suminfo_t sum; /* summary data */
+ xfs_fsblock_t sumbno; /* summary block number */
+
+ bp = NULL;
+ for (log = omp->m_rsumlevels - 1; log >= 0; log--) {
+ for (bbno = omp->m_sb.sb_rbmblocks - 1;
+ (xfs_srtblock_t)bbno >= 0;
+ bbno--) {
+ error = xfs_rtget_summary(omp, tp, log, bbno, &bp,
+ &sumbno, &sum);
+ if (error)
+ return error;
+ if (sum == 0)
+ continue;
+ error = xfs_rtmodify_summary(omp, tp, log, bbno, -sum,
+ &bp, &sumbno);
+ if (error)
+ return error;
+ error = xfs_rtmodify_summary(nmp, tp, log, bbno, sum,
+ &bp, &sumbno);
+ if (error)
+ return error;
+ ASSERT(sum > 0);
+ }
+ }
+ return 0;
+}
+
+/*
+ * Searching backward from start to limit, find the first block whose
+ * allocated/free state is different from start's.
+ */
+STATIC int /* error */
+xfs_rtfind_back(
+ xfs_mount_t *mp, /* file system mount point */
+ xfs_trans_t *tp, /* transaction pointer */
+ xfs_rtblock_t start, /* starting block to look at */
+ xfs_rtblock_t limit, /* last block to look at */
+ xfs_rtblock_t *rtblock) /* out: start block found */
+{
+ 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 firstbit; /* first useful bit in the word */
+ xfs_rtblock_t i; /* current bit number rel. to start */
+ xfs_rtblock_t len; /* length of inspected area */
+ xfs_rtword_t mask; /* mask of relevant bits for value */
+ xfs_rtword_t want; /* mask for "good" values */
+ xfs_rtword_t wdiff; /* difference from wanted value */
+ int word; /* word number in the buffer */
+
+ /*
+ * Compute and read in starting bitmap block for starting block.
+ */
+ block = XFS_BITTOBLOCK(mp, start);
+ error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
+ if (error) {
+ return error;
+ }
+ bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
+ /*
+ * Get the first word's index & point to it.
+ */
+ word = XFS_BITTOWORD(mp, start);
+ b = &bufp[word];
+ bit = (int)(start & (XFS_NBWORD - 1));
+ len = start - limit + 1;
+ /*
+ * Compute match value, based on the bit at start: if 1 (free)
+ * then all-ones, else all-zeroes.
+ */
+ want = (*b & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
+ /*
+ * If the starting position is not word-aligned, deal with the
+ * partial word.
+ */
+ if (bit < XFS_NBWORD - 1) {
+ /*
+ * Calculate first (leftmost) bit number to look at,
+ * and mask for all the relevant bits in this word.
+ */
+ firstbit = XFS_RTMAX((xfs_srtblock_t)(bit - len + 1), 0);
+ mask = (((xfs_rtword_t)1 << (bit - firstbit + 1)) - 1) <<
+ firstbit;
+ /*
+ * Calculate the difference between the value there
+ * and what we're looking for.
+ */
+ if ((wdiff = (*b ^ want) & mask)) {
+ /*
+ * Different. Mark where we are and return.
+ */
+ xfs_trans_brelse(tp, bp);
+ i = bit - XFS_RTHIBIT(wdiff);
+ *rtblock = start - i + 1;
+ return 0;
+ }
+ i = bit - firstbit + 1;
+ /*
+ * Go on to previous block if that's where the previous word is
+ * and we need the previous word.
+ */
+ if (--word == -1 && i < len) {
+ /*
+ * If done with this block, get the previous one.
+ */
+ xfs_trans_brelse(tp, bp);
+ error = xfs_rtbuf_get(mp, tp, --block, 0, &bp);
+ if (error) {
+ return error;
+ }
+ bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
+ word = XFS_BLOCKWMASK(mp);
+ b = &bufp[word];
+ } else {
+ /*
+ * Go on to the previous 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 previous one.
+ */
+ while (len - i >= XFS_NBWORD) {
+ /*
+ * Compute difference between actual and desired value.
+ */
+ if ((wdiff = *b ^ want)) {
+ /*
+ * Different, mark where we are and return.
+ */
+ xfs_trans_brelse(tp, bp);
+ i += XFS_NBWORD - 1 - XFS_RTHIBIT(wdiff);
+ *rtblock = start - i + 1;
+ return 0;
+ }
+ i += XFS_NBWORD;
+ /*
+ * Go on to previous block if that's where the previous word is
+ * and we need the previous word.
+ */
+ if (--word == -1 && i < len) {
+ /*
+ * If done with this block, get the previous one.
+ */
+ xfs_trans_brelse(tp, bp);
+ error = xfs_rtbuf_get(mp, tp, --block, 0, &bp);
+ if (error) {
+ return error;
+ }
+ bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
+ word = XFS_BLOCKWMASK(mp);
+ b = &bufp[word];
+ } else {
+ /*
+ * Go on to the previous word in the buffer.
+ */
+ b--;
+ }
+ }
+ /*
+ * If not ending on a word boundary, deal with the last
+ * (partial) word.
+ */
+ if (len - i) {
+ /*
+ * Calculate first (leftmost) bit number to look at,
+ * and mask for all the relevant bits in this word.
+ */
+ firstbit = XFS_NBWORD - (len - i);
+ mask = (((xfs_rtword_t)1 << (len - i)) - 1) << firstbit;
+ /*
+ * Compute difference between actual and desired value.
+ */
+ if ((wdiff = (*b ^ want) & mask)) {
+ /*
+ * Different, mark where we are and return.
+ */
+ xfs_trans_brelse(tp, bp);
+ i += XFS_NBWORD - 1 - XFS_RTHIBIT(wdiff);
+ *rtblock = start - i + 1;
+ return 0;
+ } else
+ i = len;
+ }
+ /*
+ * No match, return that we scanned the whole area.
+ */
+ xfs_trans_brelse(tp, bp);
+ *rtblock = start - i + 1;
+ return 0;
+}
+
+/*
+ * Searching forward from start to limit, find the first block whose
+ * allocated/free state is different from start's.
+ */
+STATIC int /* error */
+xfs_rtfind_forw(
+ xfs_mount_t *mp, /* file system mount point */
+ xfs_trans_t *tp, /* transaction pointer */
+ xfs_rtblock_t start, /* starting block to look at */
+ xfs_rtblock_t limit, /* last block to look at */
+ xfs_rtblock_t *rtblock) /* out: start block found */
+{
+ 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 the word */
+ xfs_rtblock_t len; /* length of inspected area */
+ xfs_rtword_t mask; /* mask of relevant bits for value */
+ xfs_rtword_t want; /* mask for "good" values */
+ xfs_rtword_t wdiff; /* difference from wanted value */
+ int word; /* word number in the buffer */
+
+ /*
+ * Compute and read in starting bitmap block for starting block.
+ */
+ block = XFS_BITTOBLOCK(mp, start);
+ error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
+ if (error) {
+ return error;
+ }
+ bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
+ /*
+ * Get the first word's index & point to it.
+ */
+ word = XFS_BITTOWORD(mp, start);
+ b = &bufp[word];
+ bit = (int)(start & (XFS_NBWORD - 1));
+ len = limit - start + 1;
+ /*
+ * Compute match value, based on the bit at start: if 1 (free)
+ * then all-ones, else all-zeroes.
+ */
+ want = (*b & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
+ /*
+ * If the starting position is not word-aligned, deal with the
+ * partial word.
+ */
+ if (bit) {
+ /*
+ * Calculate last (rightmost) bit number to look at,
+ * and mask for all the relevant bits in this word.
+ */
+ lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
+ mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
+ /*
+ * Calculate the difference between the value there
+ * and what we're looking for.
+ */
+ if ((wdiff = (*b ^ want) & mask)) {
+ /*
+ * Different. Mark where we are and return.
+ */
+ xfs_trans_brelse(tp, bp);
+ i = XFS_RTLOBIT(wdiff) - bit;
+ *rtblock = start + i - 1;
+ 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 previous 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 previous 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 ^ want)) {
+ /*
+ * Different, mark where we are and return.
+ */
+ xfs_trans_brelse(tp, bp);
+ i += XFS_RTLOBIT(wdiff);
+ *rtblock = start + i - 1;
+ 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)) {
+ /*
+ * Calculate mask for all the relevant bits in this word.
+ */
+ mask = ((xfs_rtword_t)1 << lastbit) - 1;
+ /*
+ * Compute difference between actual and desired value.
+ */
+ if ((wdiff = (*b ^ want) & mask)) {
+ /*
+ * Different, mark where we are and return.
+ */
+ xfs_trans_brelse(tp, bp);
+ i += XFS_RTLOBIT(wdiff);
+ *rtblock = start + i - 1;
+ return 0;
+ } else
+ i = len;
+ }
+ /*
+ * No match, return that we scanned the whole area.
+ */
+ xfs_trans_brelse(tp, bp);
+ *rtblock = start + i - 1;
+ return 0;
+}
+
+/*
+ * Mark an extent specified by start and len freed.
+ * Updates all the summary information as well as the bitmap.
+ */
+STATIC int /* error */
+xfs_rtfree_range(
+ xfs_mount_t *mp, /* file system mount point */
+ xfs_trans_t *tp, /* transaction pointer */
+ xfs_rtblock_t start, /* starting block to free */
+ xfs_extlen_t len, /* length to free */
+ 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 freed extent */
+ int error; /* error value */
+ xfs_rtblock_t postblock; /* first block freed > end */
+ xfs_rtblock_t preblock; /* first block freed < start */
+
+ end = start + len - 1;
+ /*
+ * Modify the bitmap to mark this extent freed.
+ */
+ error = xfs_rtmodify_range(mp, tp, start, len, 1);
+ if (error) {
+ return error;
+ }
+ /*
+ * Assume we're freeing out of the middle of an allocated 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 allocated extent).
+ */
+ error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
+ &postblock);
+ /*
+ * If there are blocks not being freed at the front of the
+ * old extent, add summary data for them to be allocated.
+ */
+ 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 freed at the end of the
+ * old extent, add summary data for them to be allocated.
+ */
+ 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;
+ }
+ }
+ /*
+ * Increment the summary information corresponding to the entire
+ * (new) free extent.
+ */
+ error = xfs_rtmodify_summary(mp, tp,
+ XFS_RTBLOCKLOG(postblock + 1 - preblock),
+ XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
+ return error;
+}
+
+/*
+ * Read and return the summary information for a given extent size,
+ * bitmap block combination.
+ * Keeps track of a current summary block, so we don't keep reading
+ * it from the buffer cache.
+ */
+STATIC int /* error */
+xfs_rtget_summary(
+ xfs_mount_t *mp, /* file system mount structure */
+ xfs_trans_t *tp, /* transaction pointer */
+ int log, /* log2 of 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 */
+ xfs_suminfo_t *sum) /* out: summary info for this block */
+{
+ xfs_buf_t *bp; /* buffer for summary block */
+ int error; /* error value */
+ xfs_fsblock_t sb; /* summary fsblock */
+ int so; /* index into the summary file */
+ xfs_suminfo_t *sp; /* pointer to returned data */
+
+ /*
+ * Compute entry number in the summary file.
+ */
+ so = XFS_SUMOFFS(mp, log, bbno);
+ /*
+ * Compute the block number in the summary file.
+ */
+ sb = XFS_SUMOFFSTOBLOCK(mp, so);
+ /*
+ * If we have an old buffer, and the block number matches, use that.
+ */
+ if (rbpp && *rbpp && *rsb == sb)
+ bp = *rbpp;
+ /*
+ * Otherwise we have to get the buffer.
+ */
+ else {
+ /*
+ * If there was an old one, get rid of it first.
+ */
+ if (rbpp && *rbpp)
+ xfs_trans_brelse(tp, *rbpp);
+ error = xfs_rtbuf_get(mp, tp, sb, 1, &bp);
+ if (error) {
+ return error;
+ }
+ /*
+ * Remember this buffer and block for the next call.
+ */
+ if (rbpp) {
+ *rbpp = bp;
+ *rsb = sb;
+ }
+ }
+ /*
+ * Point to the summary information & copy it out.
+ */
+ sp = XFS_SUMPTR(mp, bp, so);
+ *sum = *sp;
+ /*
+ * Drop the buffer if we're not asked to remember it.
+ */
+ if (!rbpp)
+ xfs_trans_brelse(tp, bp);
+ return 0;
+}
+
+/*
+ * Set the given range of bitmap bits to the given value.
+ * Do whatever I/O and logging is required.
+ */
+STATIC int /* error */
+xfs_rtmodify_range(
+ xfs_mount_t *mp, /* file system mount point */
+ xfs_trans_t *tp, /* transaction pointer */
+ xfs_rtblock_t start, /* starting block to modify */
+ xfs_extlen_t len, /* length of extent to modify */
+ int val) /* 1 for free, 0 for allocated */
+{
+ 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_rtword_t *first; /* first used word in the buffer */
+ int i; /* current bit number rel. to start */
+ int lastbit; /* last useful bit in word */
+ xfs_rtword_t mask; /* mask o frelevant bits for value */
+ int word; /* word number in the buffer */
+
+ /*
+ * Compute starting bitmap block number.
+ */
+ block = XFS_BITTOBLOCK(mp, start);
+ /*
+ * Read the bitmap block, and point to its data.
+ */
+ 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);
+ first = b = &bufp[word];
+ bit = (int)(start & (XFS_NBWORD - 1));
+ /*
+ * 0 (allocated) => all zeroes; 1 (free) => all ones.
+ */
+ val = -val;
+ /*
+ * If not starting on a word boundary, deal with the first
+ * (partial) word.
+ */
+ if (bit) {
+ /*
+ * Compute first bit not changed and mask of relevant bits.
+ */
+ lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
+ mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
+ /*
+ * Set/clear the active bits.
+ */
+ if (val)
+ *b |= mask;
+ else
+ *b &= ~mask;
+ i = lastbit - bit;
+ /*
+ * Go on to the next block if that's where the next word is
+ * and we need the next word.
+ */
+ if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
+ /*
+ * Log the changed part of this block.
+ * Get the next one.
+ */
+ xfs_trans_log_buf(tp, bp,
+ (uint)((char *)first - (char *)bufp),
+ (uint)((char *)b - (char *)bufp));
+ error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
+ if (error) {
+ return error;
+ }
+ first = 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) {
+ /*
+ * Set the word value correctly.
+ */
+ *b = val;
+ i += XFS_NBWORD;
+ /*
+ * Go on to the next block if that's where the next word is
+ * and we need the next word.
+ */
+ if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
+ /*
+ * Log the changed part of this block.
+ * Get the next one.
+ */
+ xfs_trans_log_buf(tp, bp,
+ (uint)((char *)first - (char *)bufp),
+ (uint)((char *)b - (char *)bufp));
+ error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
+ if (error) {
+ return error;
+ }
+ first = 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)) {
+ /*
+ * Compute a mask of relevant bits.
+ */
+ bit = 0;
+ mask = ((xfs_rtword_t)1 << lastbit) - 1;
+ /*
+ * Set/clear the active bits.
+ */
+ if (val)
+ *b |= mask;
+ else
+ *b &= ~mask;
+ b++;
+ }
+ /*
+ * Log any remaining changed bytes.
+ */
+ if (b > first)
+ xfs_trans_log_buf(tp, bp, (uint)((char *)first - (char *)bufp),
+ (uint)((char *)b - (char *)bufp - 1));
+ return 0;
+}
+
+/*
+ * Read and modify the summary information for a given extent size,
+ * bitmap block combination.
+ * Keeps track of a current summary block, so we don't keep reading
+ * it from the buffer cache.
+ */
+STATIC int /* error */
+xfs_rtmodify_summary(
+ xfs_mount_t *mp, /* file system mount point */
+ xfs_trans_t *tp, /* transaction pointer */
+ int log, /* log2 of extent size */
+ xfs_rtblock_t bbno, /* bitmap block number */
+ int delta, /* change to make to summary info */
+ xfs_buf_t **rbpp, /* in/out: summary block buffer */
+ xfs_fsblock_t *rsb) /* in/out: summary block number */
+{
+ xfs_buf_t *bp; /* buffer for the summary block */
+ int error; /* error value */
+ xfs_fsblock_t sb; /* summary fsblock */
+ int so; /* index into the summary file */
+ xfs_suminfo_t *sp; /* pointer to returned data */
+
+ /*
+ * Compute entry number in the summary file.
+ */
+ so = XFS_SUMOFFS(mp, log, bbno);
+ /*
+ * Compute the block number in the summary file.
+ */
+ sb = XFS_SUMOFFSTOBLOCK(mp, so);
+ /*
+ * If we have an old buffer, and the block number matches, use that.
+ */
+ if (rbpp && *rbpp && *rsb == sb)
+ bp = *rbpp;
+ /*
+ * Otherwise we have to get the buffer.
+ */
+ else {
+ /*
+ * If there was an old one, get rid of it first.
+ */
+ if (rbpp && *rbpp)
+ xfs_trans_brelse(tp, *rbpp);
+ error = xfs_rtbuf_get(mp, tp, sb, 1, &bp);
+ if (error) {
+ return error;
+ }
+ /*
+ * Remember this buffer and block for the next call.
+ */
+ if (rbpp) {
+ *rbpp = bp;
+ *rsb = sb;
+ }
+ }
+ /*
+ * Point to the summary information, modify and log it.
+ */
+ sp = XFS_SUMPTR(mp, bp, so);
+ *sp += delta;
+ xfs_trans_log_buf(tp, bp, (uint)((char *)sp - (char *)XFS_BUF_PTR(bp)),
+ (uint)((char *)sp - (char *)XFS_BUF_PTR(bp) + sizeof(*sp) - 1));
+ return 0;
+}
+
+/*
+ * Visible (exported) functions.
+ */
+
+/*
+ * Grow the realtime area of the filesystem.
+ */
+int
+xfs_growfs_rt(
+ xfs_mount_t *mp, /* mount point for filesystem */
+ xfs_growfs_rt_t *in) /* growfs rt input struct */
+{
+ xfs_rtblock_t bmbno; /* bitmap block number */
+ xfs_buf_t *bp; /* temporary buffer */
+ int cancelflags; /* flags for xfs_trans_cancel */
+ int error; /* error return value */
+ xfs_inode_t *ip; /* bitmap inode, used as lock */
+ xfs_mount_t *nmp; /* new (fake) mount structure */
+ xfs_drfsbno_t nrblocks; /* new number of realtime blocks */
+ xfs_extlen_t nrbmblocks; /* new number of rt bitmap blocks */
+ xfs_drtbno_t nrextents; /* new number of realtime extents */
+ uint8_t nrextslog; /* new log2 of sb_rextents */
+ xfs_extlen_t nrsumblocks; /* new number of summary blocks */
+ uint nrsumlevels; /* new rt summary levels */
+ uint nrsumsize; /* new size of rt summary, bytes */
+ xfs_sb_t *nsbp; /* new superblock */
+ xfs_extlen_t rbmblocks; /* current number of rt bitmap blocks */
+ xfs_extlen_t rsumblocks; /* current number of rt summary blks */
+ xfs_sb_t *sbp; /* old superblock */
+ xfs_fsblock_t sumbno; /* summary block number */
+ xfs_trans_t *tp; /* transaction pointer */
+
+ sbp = &mp->m_sb;
+ /*
+ * Initial error checking.
+ */
+ if (mp->m_rtdev_targp || mp->m_rbmip == NULL ||
+ (nrblocks = in->newblocks) <= sbp->sb_rblocks ||
+ (sbp->sb_rblocks && (in->extsize != sbp->sb_rextsize)))
+ return XFS_ERROR(EINVAL);
+ /*
+ * Read in the last block of the device, make sure it exists.
+ */
+ error = xfs_read_buf(mp, mp->m_rtdev_targp,
+ XFS_FSB_TO_BB(mp, in->newblocks - 1),
+ XFS_FSB_TO_BB(mp, 1), 0, &bp);
+ if (error)
+ return error;
+ ASSERT(bp);
+ xfs_buf_relse(bp);
+ /*
+ * Calculate new parameters. These are the final values to be reached.
+ */
+ nrextents = nrblocks;
+ do_div(nrextents, in->extsize);
+ nrbmblocks = roundup_64(nrextents, NBBY * sbp->sb_blocksize);
+ nrextslog = xfs_highbit32(nrextents);
+ nrsumlevels = nrextslog + 1;
+ nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
+ nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
+ nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
+ /*
+ * New summary size can't be more than half the size of
+ * the log. This prevents us from getting a log overflow,
+ * since we'll log basically the whole summary file at once.
+ */
+ if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
+ return XFS_ERROR(EINVAL);
+ /*
+ * Get the old block counts for bitmap and summary inodes.
+ * These can't change since other growfs callers are locked out.
+ */
+ rbmblocks = XFS_B_TO_FSB(mp, mp->m_rbmip->i_d.di_size);
+ rsumblocks = XFS_B_TO_FSB(mp, mp->m_rsumip->i_d.di_size);
+ /*
+ * Allocate space to the bitmap and summary files, as necessary.
+ */
+ if ((error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks,
+ mp->m_sb.sb_rbmino)))
+ return error;
+ if ((error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks,
+ mp->m_sb.sb_rsumino)))
+ return error;
+ nmp = NULL;
+ /*
+ * Loop over the bitmap blocks.
+ * We will do everything one bitmap block at a time.
+ * Skip the current block if it is exactly full.
+ * This also deals with the case where there were no rtextents before.
+ */
+ for (bmbno = sbp->sb_rbmblocks -
+ ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
+ bmbno < nrbmblocks;
+ bmbno++) {
+ /*
+ * Allocate a new (fake) mount/sb.
+ */
+ nmp = kmem_alloc(sizeof(*nmp), KM_SLEEP);
+ *nmp = *mp;
+ nsbp = &nmp->m_sb;
+ /*
+ * Calculate new sb and mount fields for this round.
+ */
+ nsbp->sb_rextsize = in->extsize;
+ nsbp->sb_rbmblocks = bmbno + 1;
+ nsbp->sb_rblocks =
+ XFS_RTMIN(nrblocks,
+ nsbp->sb_rbmblocks * NBBY *
+ nsbp->sb_blocksize * nsbp->sb_rextsize);
+ nsbp->sb_rextents = nsbp->sb_rblocks;
+ do_div(nsbp->sb_rextents, nsbp->sb_rextsize);
+ nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
+ nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
+ nrsumsize =
+ (uint)sizeof(xfs_suminfo_t) * nrsumlevels *
+ nsbp->sb_rbmblocks;
+ nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
+ nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
+ /*
+ * Start a transaction, get the log reservation.
+ */
+ tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_FREE);
+ cancelflags = 0;
+ if ((error = xfs_trans_reserve(tp, 0,
+ XFS_GROWRTFREE_LOG_RES(nmp), 0, 0, 0)))
+ goto error_exit;
+ /*
+ * Lock out other callers by grabbing the bitmap inode lock.
+ */
+ if ((error = xfs_trans_iget(mp, tp, 0, mp->m_sb.sb_rbmino,
+ XFS_ILOCK_EXCL, &ip)))
+ goto error_exit;
+ ASSERT(ip == mp->m_rbmip);
+ /*
+ * Update the bitmap inode's size.
+ */
+ mp->m_rbmip->i_d.di_size =
+ nsbp->sb_rbmblocks * nsbp->sb_blocksize;
+ xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
+ cancelflags |= XFS_TRANS_ABORT;
+ /*
+ * Get the summary inode into the transaction.
+ */
+ if ((error = xfs_trans_iget(mp, tp, mp->m_sb.sb_rsumino,
+ 0, XFS_ILOCK_EXCL, &ip)))
+ goto error_exit;
+ ASSERT(ip == mp->m_rsumip);
+ /*
+ * Update the summary inode's size.
+ */
+ mp->m_rsumip->i_d.di_size = nmp->m_rsumsize;
+ xfs_trans_log_inode(tp, mp->m_rsumip, XFS_ILOG_CORE);
+ /*
+ * Copy summary data from old to new sizes.
+ * Do this when the real size (not block-aligned) changes.
+ */
+ if (sbp->sb_rbmblocks != nsbp->sb_rbmblocks ||
+ mp->m_rsumlevels != nmp->m_rsumlevels) {
+ error = xfs_rtcopy_summary(mp, nmp, tp);
+ if (error)
+ goto error_exit;
+ }
+ /*
+ * Update superblock fields.
+ */
+ if (nsbp->sb_rextsize != sbp->sb_rextsize)
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSIZE,
+ nsbp->sb_rextsize - sbp->sb_rextsize);
+ if (nsbp->sb_rbmblocks != sbp->sb_rbmblocks)
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
+ nsbp->sb_rbmblocks - sbp->sb_rbmblocks);
+ if (nsbp->sb_rblocks != sbp->sb_rblocks)
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBLOCKS,
+ nsbp->sb_rblocks - sbp->sb_rblocks);
+ if (nsbp->sb_rextents != sbp->sb_rextents)
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTENTS,
+ nsbp->sb_rextents - sbp->sb_rextents);
+ if (nsbp->sb_rextslog != sbp->sb_rextslog)
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
+ nsbp->sb_rextslog - sbp->sb_rextslog);
+ /*
+ * Free new extent.
+ */
+ bp = NULL;
+ error = xfs_rtfree_range(nmp, tp, sbp->sb_rextents,
+ nsbp->sb_rextents - sbp->sb_rextents, &bp, &sumbno);
+ if (error)
+ goto error_exit;
+ /*
+ * Mark more blocks free in the superblock.
+ */
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS,
+ nsbp->sb_rextents - sbp->sb_rextents);
+ /*
+ * Free the fake mp structure.
+ */
+ kmem_free(nmp, sizeof(*nmp));
+ nmp = NULL;
+ /*
+ * Update mp values into the real mp structure.
+ */
+ mp->m_rsumlevels = nrsumlevels;
+ mp->m_rsumsize = nrsumsize;
+ /*
+ * Commit the transaction.
+ */
+ xfs_trans_commit(tp, 0, NULL);
+ }
+ return 0;
+
+ /*
+ * Error paths come here.
+ */
+error_exit:
+ if (nmp)
+ kmem_free(nmp, sizeof(*nmp));
+ xfs_trans_cancel(tp, cancelflags);
+ return error;
+}
+
+/*
+ * Allocate an extent in the realtime subvolume, with the usual allocation
+ * parameters. The length units are all in realtime extents, as is the
+ * result block number.
+ */
+int /* error */
+xfs_rtallocate_extent(
+ 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_alloctype_t type, /* allocation type XFS_ALLOCTYPE... */
+ int wasdel, /* was a delayed allocation extent */
+ xfs_extlen_t prod, /* extent product factor */
+ xfs_rtblock_t *rtblock) /* out: start block allocated */
+{
+ int error; /* error value */
+ xfs_inode_t *ip; /* inode for bitmap file */
+ xfs_mount_t *mp; /* file system mount structure */
+ xfs_rtblock_t r; /* result allocated block */
+ xfs_fsblock_t sb; /* summary file block number */
+ xfs_buf_t *sumbp; /* summary file block buffer */
+
+ ASSERT(minlen > 0 && minlen <= maxlen);
+ mp = tp->t_mountp;
+ /*
+ * If prod is set then figure out what to do to minlen and maxlen.
+ */
+ if (prod > 1) {
+ xfs_extlen_t i;
+
+ if ((i = maxlen % prod))
+ maxlen -= i;
+ if ((i = minlen % prod))
+ minlen += prod - i;
+ if (maxlen < minlen) {
+ *rtblock = NULLRTBLOCK;
+ return 0;
+ }
+ }
+ /*
+ * Lock out other callers by grabbing the bitmap inode lock.
+ */
+ error = xfs_trans_iget(mp, tp, mp->m_sb.sb_rbmino, 0, XFS_ILOCK_EXCL, &ip);
+ if (error) {
+ return error;
+ }
+ sumbp = NULL;
+ /*
+ * Allocate by size, or near another block, or exactly at some block.
+ */
+ switch (type) {
+ case XFS_ALLOCTYPE_ANY_AG:
+ error = xfs_rtallocate_extent_size(mp, tp, minlen, maxlen, len,
+ &sumbp, &sb, prod, &r);
+ break;
+ case XFS_ALLOCTYPE_NEAR_BNO:
+ error = xfs_rtallocate_extent_near(mp, tp, bno, minlen, maxlen,
+ len, &sumbp, &sb, prod, &r);
+ break;
+ case XFS_ALLOCTYPE_THIS_BNO:
+ error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen,
+ len, &sumbp, &sb, prod, &r);
+ break;
+ default:
+ ASSERT(0);
+ }
+ if (error) {
+ return error;
+ }
+ /*
+ * If it worked, update the superblock.
+ */
+ if (r != NULLRTBLOCK) {
+ long slen = (long)*len;
+
+ ASSERT(*len >= minlen && *len <= maxlen);
+ if (wasdel)
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
+ else
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
+ }
+ *rtblock = r;
+ return 0;
+}
+
+/*
+ * Free an extent in the realtime subvolume. Length is expressed in
+ * realtime extents, as is the block number.
+ */
+int /* error */
+xfs_rtfree_extent(
+ xfs_trans_t *tp, /* transaction pointer */
+ xfs_rtblock_t bno, /* starting block number to free */
+ xfs_extlen_t len) /* length of extent freed */
+{
+ int error; /* error value */
+ xfs_inode_t *ip; /* bitmap file inode */
+ xfs_mount_t *mp; /* file system mount structure */
+ xfs_fsblock_t sb; /* summary file block number */
+ xfs_buf_t *sumbp; /* summary file block buffer */
+
+ mp = tp->t_mountp;
+ /*
+ * Synchronize by locking the bitmap inode.
+ */
+ error = xfs_trans_iget(mp, tp, mp->m_sb.sb_rbmino, 0, XFS_ILOCK_EXCL, &ip);
+ if (error) {
+ return error;
+ }
+#if defined(__KERNEL__) && defined(DEBUG)
+ /*
+ * Check to see that this whole range is currently allocated.
+ */
+ {
+ int stat; /* result from checking range */
+
+ error = xfs_rtcheck_alloc_range(mp, tp, bno, len, &stat);
+ if (error) {
+ return error;
+ }
+ ASSERT(stat);
+ }
+#endif
+ sumbp = NULL;
+ /*
+ * Free the range of realtime blocks.
+ */
+ error = xfs_rtfree_range(mp, tp, bno, len, &sumbp, &sb);
+ if (error) {
+ return error;
+ }
+ /*
+ * Mark more blocks free in the superblock.
+ */
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, (long)len);
+ /*
+ * If we've now freed all the blocks, reset the file sequence
+ * number to 0.
+ */
+ if (tp->t_frextents_delta + mp->m_sb.sb_frextents ==
+ mp->m_sb.sb_rextents) {
+ if (!(ip->i_d.di_flags & XFS_DIFLAG_NEWRTBM))
+ ip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
+ *(__uint64_t *)&ip->i_d.di_atime = 0;
+ xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+ }
+ return 0;
+}
+
+/*
+ * Initialize realtime fields in the mount structure.
+ */
+int /* error */
+xfs_rtmount_init(
+ xfs_mount_t *mp) /* file system mount structure */
+{
+ xfs_buf_t *bp; /* buffer for last block of subvolume */
+ xfs_daddr_t d; /* address of last block of subvolume */
+ int error; /* error return value */
+ xfs_sb_t *sbp; /* filesystem superblock copy in mount */
+
+ sbp = &mp->m_sb;
+ if (sbp->sb_rblocks == 0)
+ return 0;
+ if (mp->m_rtdev_targp == NULL) {
+ cmn_err(CE_WARN,
+ "XFS: This filesystem has a realtime volume, use rtdev=device option");
+ return XFS_ERROR(ENODEV);
+ }
+ mp->m_rsumlevels = sbp->sb_rextslog + 1;
+ mp->m_rsumsize =
+ (uint)sizeof(xfs_suminfo_t) * mp->m_rsumlevels *
+ sbp->sb_rbmblocks;
+ mp->m_rsumsize = roundup(mp->m_rsumsize, sbp->sb_blocksize);
+ mp->m_rbmip = mp->m_rsumip = NULL;
+ /*
+ * Check that the realtime section is an ok size.
+ */
+ d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
+ if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_rblocks) {
+ cmn_err(CE_WARN, "XFS: realtime mount -- %llu != %llu",
+ (unsigned long long) XFS_BB_TO_FSB(mp, d),
+ (unsigned long long) mp->m_sb.sb_rblocks);
+ return XFS_ERROR(E2BIG);
+ }
+ error = xfs_read_buf(mp, mp->m_rtdev_targp,
+ d - XFS_FSB_TO_BB(mp, 1),
+ XFS_FSB_TO_BB(mp, 1), 0, &bp);
+ if (error) {
+ cmn_err(CE_WARN,
+ "XFS: realtime mount -- xfs_read_buf failed, returned %d", error);
+ if (error == ENOSPC)
+ return XFS_ERROR(E2BIG);
+ return error;
+ }
+ xfs_buf_relse(bp);
+ return 0;
+}
+
+/*
+ * Get the bitmap and summary inodes into the mount structure
+ * at mount time.
+ */
+int /* error */
+xfs_rtmount_inodes(
+ xfs_mount_t *mp) /* file system mount structure */
+{
+ int error; /* error return value */
+ xfs_sb_t *sbp;
+
+ sbp = &mp->m_sb;
+ if (sbp->sb_rbmino == NULLFSINO)
+ return 0;
+ error = xfs_iget(mp, NULL, sbp->sb_rbmino, 0, 0, &mp->m_rbmip, 0);
+ if (error)
+ return error;
+ ASSERT(mp->m_rbmip != NULL);
+ ASSERT(sbp->sb_rsumino != NULLFSINO);
+ error = xfs_iget(mp, NULL, sbp->sb_rsumino, 0, 0, &mp->m_rsumip, 0);
+ if (error) {
+ VN_RELE(XFS_ITOV(mp->m_rbmip));
+ return error;
+ }
+ ASSERT(mp->m_rsumip != NULL);
+ return 0;
+}
+
+/*
+ * Pick an extent for allocation at the start of a new realtime file.
+ * Use the sequence number stored in the atime field of the bitmap inode.
+ * Translate this to a fraction of the rtextents, and return the product
+ * of rtextents and the fraction.
+ * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
+ */
+int /* error */
+xfs_rtpick_extent(
+ xfs_mount_t *mp, /* file system mount point */
+ xfs_trans_t *tp, /* transaction pointer */
+ xfs_extlen_t len, /* allocation length (rtextents) */
+ xfs_rtblock_t *pick) /* result rt extent */
+{
+ xfs_rtblock_t b; /* result block */
+ int error; /* error return value */
+ xfs_inode_t *ip; /* bitmap incore inode */
+ int log2; /* log of sequence number */
+ __uint64_t resid; /* residual after log removed */
+ __uint64_t seq; /* sequence number of file creation */
+ __uint64_t *seqp; /* pointer to seqno in inode */
+
+ error = xfs_trans_iget(mp, tp, mp->m_sb.sb_rbmino, 0, XFS_ILOCK_EXCL, &ip);
+ if (error)
+ return error;
+ ASSERT(ip == mp->m_rbmip);
+ seqp = (__uint64_t *)&ip->i_d.di_atime;
+ if (!(ip->i_d.di_flags & XFS_DIFLAG_NEWRTBM)) {
+ ip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
+ *seqp = 0;
+ }
+ seq = *seqp;
+ if ((log2 = xfs_highbit64(seq)) == -1)
+ b = 0;
+ else {
+ resid = seq - (1ULL << log2);
+ b = (mp->m_sb.sb_rextents * ((resid << 1) + 1ULL)) >>
+ (log2 + 1);
+ if (b >= mp->m_sb.sb_rextents)
+ b = do_mod(b, mp->m_sb.sb_rextents);
+ if (b + len > mp->m_sb.sb_rextents)
+ b = mp->m_sb.sb_rextents - len;
+ }
+ *seqp = seq + 1;
+ xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+ *pick = b;
+ return 0;
+}
+
+#ifdef DEBUG
+/*
+ * Debug code: print out the value of a range in the bitmap.
+ */
+void
+xfs_rtprint_range(
+ xfs_mount_t *mp, /* file system mount structure */
+ xfs_trans_t *tp, /* transaction pointer */
+ xfs_rtblock_t start, /* starting block to print */
+ xfs_extlen_t len) /* length to print */
+{
+ xfs_extlen_t i; /* block number in the extent */
+
+ printk("%Ld: ", (long long)start);
+ for (i = 0; i < len; i++)
+ printk("%d", xfs_rtcheck_bit(mp, tp, start + i, 1));
+ printk("\n");
+}
+
+/*
+ * Debug code: print the summary file.
+ */
+void
+xfs_rtprint_summary(
+ xfs_mount_t *mp, /* file system mount structure */
+ xfs_trans_t *tp) /* transaction pointer */
+{
+ xfs_suminfo_t c; /* summary data */
+ xfs_rtblock_t i; /* bitmap block number */
+ int l; /* summary information level */
+ int p; /* flag for printed anything */
+ xfs_fsblock_t sb; /* summary block number */
+ xfs_buf_t *sumbp; /* summary block buffer */
+
+ sumbp = NULL;
+ for (l = 0; l < mp->m_rsumlevels; l++) {
+ for (p = 0, i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
+ (void)xfs_rtget_summary(mp, tp, l, i, &sumbp, &sb, &c);
+ if (c) {
+ if (!p) {
+ printk("%Ld-%Ld:", 1LL << l,
+ XFS_RTMIN((1LL << l) +
+ ((1LL << l) - 1LL),
+ mp->m_sb.sb_rextents));
+ p = 1;
+ }
+ printk(" %Ld:%d", (long long)i, c);
+ }
+ }
+ if (p)
+ printk("\n");
+ }
+ if (sumbp)
+ xfs_trans_brelse(tp, sumbp);
+}
+#endif /* DEBUG */
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