File: [Development] / xfs-linux-nodel / xfs_rtalloc.c (download)
Revision 1.36, Thu Dec 12 01:46:53 1996 UTC (20 years, 10 months ago) by doucette
Branch: MAIN
Changes since 1.35: +4 -0
lines
Fix some warnings: remove unused variables, add ARGSUSED and REFERENCED,
add casts.
|
#ident "$Revision: 1.34 $"
/*
* 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/uuid.h>
#include <sys/grio.h>
#include <sys/debug.h>
#ifdef SIM
#undef _KERNEL
#endif
#include <sys/vnode.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.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
#if !defined(SIM) || defined(DEBUG)
/*
* 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 */
#endif /* !SIM */
/*
* 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 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(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
#if !defined(SIM) || defined(DEBUG)
/*
* 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;
}
#endif /* !SIM && !DEBUG */
/*
* 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) {
long slen = (long)*len;
ASSERT(*len >= minlen && *len <= maxlen);
if (wasdel)
xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
else
xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
}
*rtblock = r;
return 0;
}
#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, (long)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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