/fs/xfs/xfs_rtalloc.c
C | 2469 lines | 1495 code | 69 blank | 905 comment | 293 complexity | d804284312fe0d3edb8a8c4c1967d33c MD5 | raw file
Possible License(s): CC-BY-SA-3.0, GPL-2.0, LGPL-2.0
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- /*
- * 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)…
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