File: [Development] / linux-2.6-xfs / fs / xfs / xfs_rtalloc.c (download)
Revision 1.29, Mon Aug 7 19:20:10 1995 UTC (22 years, 2 months ago) by doucette
Branch: MAIN
Changes since 1.28: +1329 -497
lines
Make minimum rt extent size 4k instead of 64k.
Finally add comments to this file. Fix Tom's last bug fix, there
was code at the wrong nesting level. This caused unnecessary gaps
in the allocations.
|
#ident "$Revision: 1.28 $"
/*
* Free realtime space allocation for XFS.
*/
#ifdef SIM
#define _KERNEL 1
#endif
#include <sys/param.h>
#include <sys/buf.h>
#include <sys/time.h>
#include <sys/grio.h>
#ifdef SIM
#undef _KERNEL
#endif
#include <sys/vnode.h>
#include <sys/debug.h>
#include <stddef.h>
#ifdef SIM
#include <stdlib.h>
#include <bstring.h>
#include <stdio.h>
#else
#include <sys/systm.h>
#endif
#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_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_dinode.h"
#include "xfs_inode_item.h"
#include "xfs_inode.h"
#include "xfs_alloc.h"
#include "xfs_bmap.h"
#include "xfs_bit.h"
#include "xfs_rtalloc.h"
#ifdef SIM
#include "sim.h"
#endif
/*
* Prototypes for internal functions.
*/
#ifndef SIM
/*
* 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_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 */
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 */
/*
* 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_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 */
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 */
/*
* 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_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 */
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 */
/*
* 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_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 */
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 */
/*
* 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_trans_t *tp, /* transaction pointer */
xfs_rtblock_t start, /* start block to allocate */
xfs_extlen_t len, /* length to allocate */
buf_t **rbpp, /* in/out: summary block buffer */
xfs_fsblock_t *rsb); /* in/out: summary block number */
/*
* 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 */
buf_t **rbpp, /* in/out: summary block buffer */
xfs_fsblock_t *rsb, /* in/out: summary block number */
int *stat); /* out: any good extents here? */
#endif /* !SIM */
/*
* 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 */
buf_t **bpp); /* output: buffer for the block */
#ifdef DEBUG
/*
* Check that the given extent (block range) is allocated already.
*/
STATIC int /* error */
xfs_rtcheck_alloc_range(
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 */
#endif
#ifdef XFSDEBUG
/*
* 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 */
#endif /* XFSDEBUG */
#if 0
/*
* Check that the given extent (block range) is free already.
*/
STATIC int /* error */
xfs_rtcheck_free_range(
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 */
#endif
/*
* Check that the given range is either all allocated (val = 0) or
* all free (val = 1).
*/
STATIC int /* error */
xfs_rtcheck_range(
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 */
/*
* 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_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 */
/*
* 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_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 */
/*
* 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_trans_t *tp, /* transaction pointer */
xfs_rtblock_t start, /* starting block to free */
xfs_extlen_t len, /* length to free */
buf_t **rbpp, /* in/out: summary block buffer */
xfs_fsblock_t *rsb); /* in/out: summary block number */
#if defined(XFSDEBUG) || !defined(SIM)
/*
* 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 */
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 */
#endif /* XFSDEBUG || !SIM */
/*
* 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_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 */
/*
* 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_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 */
buf_t **rbpp, /* in/out: summary block buffer */
xfs_fsblock_t *rsb); /* in/out: summary block number */
/*
* Internal functions.
*/
#ifndef SIM
/*
* 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_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 */
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_mount_t *mp; /* file system mount structure */
xfs_rtblock_t next; /* next rtblock to try */
int stat; /* status from internal calls */
ASSERT(minlen % prod == 0 && maxlen % prod == 0);
mp = tp->t_mountp;
/*
* 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(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(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(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 = bestlen % prod))
bestlen -= p;
/*
* Allocate besti for bestlen & return that.
*/
error = xfs_rtallocate_range(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_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 */
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(tp, bno, maxlen, 1, &next, &isfree);
if (error) {
return error;
}
if (isfree) {
/*
* If it is, allocate it and return success.
*/
error = xfs_rtallocate_range(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(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_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 */
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_mount_t *mp; /* file system mount structure */
xfs_rtblock_t n; /* next block to try */
xfs_rtblock_t r; /* result block */
ASSERT(minlen % prod == 0 && maxlen % prod == 0);
mp = tp->t_mountp;
/*
* 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(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(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(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(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_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 */
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_mount_t *mp; /* file system mount structure */
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);
mp = tp->t_mountp;
/*
* 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(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(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_trans_t *tp, /* transaction pointer */
xfs_rtblock_t start, /* start block to allocate */
xfs_extlen_t len, /* length to allocate */
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_mount_t *mp; /* file system mount structure */
xfs_rtblock_t postblock; /* first block allocated > end */
xfs_rtblock_t preblock; /* first block allocated < start */
mp = tp->t_mountp;
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(tp, start, 0, &preblock);
if (error) {
return error;
}
/*
* Find the next allocated block (end of free extent).
*/
error = xfs_rtfind_forw(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(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(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(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(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 */
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;
}
#endif /* !SIM */
/*
* 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 */
buf_t **bpp) /* output: buffer for the block */
{
buf_t *bp; /* block buffer, result */
daddr_t d; /* disk addr of block */
int error; /* error value */
xfs_fsblock_t firstblock; /* first alloc block for bmap */
xfs_bmap_free_t *flist; /* block freed list for bmap */
xfs_inode_t *ip; /* bitmap or summary inode */
xfs_bmbt_irec_t map; /* block map results */
int nmap; /* number of entries in "map" */
nmap = 1;
flist = NULL;
ip = issum ? mp->m_rsumip : mp->m_rbmip;
firstblock = NULLFSBLOCK;
/*
* Map from the file offset (block) and inode number to the
* file system block.
*/
error = xfs_bmapi(tp, ip, block, 1, 0, &firstblock, 0, &map, &nmap,
flist);
if (error) {
return error;
}
ASSERT(nmap == 1);
ASSERT(flist == NULL);
ASSERT(firstblock == NULLFSBLOCK);
/*
* Convert to disk address for buffer cache.
*/
d = XFS_FSB_TO_DADDR(mp, map.br_startblock);
/*
* Read the buffer.
*/
error = xfs_trans_read_buf(tp, mp->m_dev, d, mp->m_bsize, 0, &bp);
if (error) {
return error;
}
ASSERT(bp && !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_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(tp, bno, len, 0, &new, stat);
}
#endif
#ifdef XFSDEBUG
/*
* 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 */
buf_t *bp; /* buf for the block */
xfs_rtword_t *bufp; /* pointer into the buffer */
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);
bp = xfs_rtbuf_get(mp, tp, block, 0);
bufp = (xfs_rtword_t *)bp->b_un.b_addr;
word = XFS_BITTOWORD(mp, start);
bit = start & (XFS_NBWORD - 1);
wval = bufp[word];
xfs_trans_brelse(tp, bp);
wdiff = (wval ^ -val) & ((xfs_rtword_t)1 << bit);
return !wdiff;
}
#endif /* XFSDEBUG */
#if 0
/*
* Check that the given extent (block range) is free already.
*/
STATIC int /* error */
xfs_rtcheck_free_range(
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(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_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 */
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_mount_t *mp; /* file system mount structure */
xfs_rtword_t wdiff; /* difference from wanted value */
int word; /* word number in the buffer */
mp = tp->t_mountp;
/*
* 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 *)bp->b_un.b_addr;
/*
* Compute the starting word's address, and starting bit.
*/
word = XFS_BITTOWORD(mp, start);
b = &bufp[word];
bit = 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 *)bp->b_un.b_addr;
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 *)bp->b_un.b_addr;
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;
}
/*
* 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_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 */
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_mount_t *mp; /* file system mount structure */
xfs_rtword_t want; /* mask for "good" values */
xfs_rtword_t wdiff; /* difference from wanted value */
int word; /* word number in the buffer */
mp = tp->t_mountp;
/*
* 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 *)bp->b_un.b_addr;
/*
* Get the first word's index & point to it.
*/
word = XFS_BITTOWORD(mp, start);
b = &bufp[word];
bit = 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 *)bp->b_un.b_addr;
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 *)bp->b_un.b_addr;
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_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 */
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_mount_t *mp; /* file system mount structure */
xfs_rtword_t want; /* mask for "good" values */
xfs_rtword_t wdiff; /* difference from wanted value */
int word; /* word number in the buffer */
mp = tp->t_mountp;
/*
* 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 *)bp->b_un.b_addr;
/*
* Get the first word's index & point to it.
*/
word = XFS_BITTOWORD(mp, start);
b = &bufp[word];
bit = 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 *)bp->b_un.b_addr;
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 *)bp->b_un.b_addr;
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_trans_t *tp, /* transaction pointer */
xfs_rtblock_t start, /* starting block to free */
xfs_extlen_t len, /* length to free */
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_mount_t *mp; /* file system mount structure */
xfs_rtblock_t postblock; /* first block freed > end */
xfs_rtblock_t preblock; /* first block freed < start */
mp = tp->t_mountp;
end = start + len - 1;
/*
* Modify the bitmap to mark this extent freed.
*/
error = xfs_rtmodify_range(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(tp, start, 0, &preblock);
if (error) {
return error;
}
/*
* Find the next allocated block (end of allocated extent).
*/
error = xfs_rtfind_forw(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(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(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(tp,
XFS_RTBLOCKLOG(postblock + 1 - preblock),
XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
return error;
}
#if defined(XFSDEBUG) || !defined(SIM)
/*
* 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 */
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 */
{
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;
}
#endif /* XFSDEBUG || !SIM */
/*
* 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_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 */
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 */
xfs_mount_t *mp; /* file system mount structure */
int word; /* word number in the buffer */
mp = tp->t_mountp;
/*
* 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 *)bp->b_un.b_addr;
/*
* Compute the starting word's address, and starting bit.
*/
word = XFS_BITTOWORD(mp, start);
first = b = &bufp[word];
bit = 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, (char *)first - (char *)bufp,
(char *)b - (char *)bufp);
error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
if (error) {
return error;
}
first = b = bufp = (xfs_rtword_t *)bp->b_un.b_addr;
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, (char *)first - (char *)bufp,
(char *)b - (char *)bufp);
error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
if (error) {
return error;
}
first = b = bufp = (xfs_rtword_t *)bp->b_un.b_addr;
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, (char *)first - (char *)bufp,
(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_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 */
buf_t **rbpp, /* in/out: summary block buffer */
xfs_fsblock_t *rsb) /* in/out: summary block number */
{
buf_t *bp; /* buffer for the summary block */
int error; /* error value */
xfs_mount_t *mp; /* file system mount structure */
xfs_fsblock_t sb; /* summary fsblock */
int so; /* index into the summary file */
xfs_suminfo_t *sp; /* pointer to returned data */
mp = tp->t_mountp;
/*
* 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, (char *)sp - (char *)bp->b_un.b_addr,
(char *)sp - (char *)bp->b_un.b_addr + sizeof(*sp) - 1);
return 0;
}
/*
* Visible (exported) functions.
*/
#ifndef SIM
/*
* 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 */
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, 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(tp, minlen, maxlen, len,
&sumbp, &sb, prod, &r);
break;
case XFS_ALLOCTYPE_NEAR_BNO:
error = xfs_rtallocate_extent_near(tp, bno, minlen, maxlen,
len, &sumbp, &sb, prod, &r);
break;
case XFS_ALLOCTYPE_THIS_BNO:
error = xfs_rtallocate_extent_exact(tp, bno, minlen, maxlen,
len, &sumbp, &sb, prod, &r);
break;
}
if (error) {
return error;
}
/*
* If it worked, update the superblock.
*/
if (r != NULLRTBLOCK) {
int slen = (int)*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;
}
#endif /* !SIM */
/*
* 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 */
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, XFS_ILOCK_EXCL, &ip);
if (error) {
return error;
}
#ifdef DEBUG
/*
* Check to see that this whole range is currently allocated.
*/
{
int stat; /* result from checking range */
error = xfs_rtcheck_alloc_range(tp, bno, len, &stat);
if (error) {
return error;
}
ASSERT(stat);
}
#endif
sumbp = NULL;
/*
* Free the range of realtime blocks.
*/
error = xfs_rtfree_range(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, (int)len);
return 0;
}
#ifdef XFSDEBUG
/*
* 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 */
printf("%lld: ", start);
for (i = 0; i < len; i++)
printf("%d", xfs_rtcheck_bit(mp, tp, start + i, 1));
printf("\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 */
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) {
printf("%lld-%lld:", 1LL << l,
XFS_RTMIN((1LL << l) +
((1LL << l) - 1LL),
mp->m_sb.sb_rextents));
p = 1;
}
printf(" %lld:%d", i, c);
}
}
if (p)
printf("\n");
}
if (sumbp)
xfs_trans_brelse(tp, sumbp);
}
#endif /* XFSDEBUG */
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