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/*
* Copyright (c) 2000 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* Further, this software is distributed without any warranty that it is
* free of the rightful claim of any third person regarding infringement
* or the like. Any license provided herein, whether implied or
* otherwise, applies only to this software file. Patent licenses, if
* any, provided herein do not apply to combinations of this program with
* other software, or any other product whatsoever.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
* Mountain View, CA 94043, or:
*
* http://www.sgi.com
*
* For further information regarding this notice, see:
*
* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
*/
/*
* This file contains common code for the space manager's btree implementations.
*/
#include <xfs.h>
/*
* Cursor allocation zone.
*/
xfs_zone_t *xfs_btree_cur_zone;
/*
* Btree magic numbers.
*/
const __uint32_t xfs_magics[XFS_BTNUM_MAX] =
{
XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, XFS_BMAP_MAGIC, XFS_IBT_MAGIC
};
/*
* Prototypes for internal routines.
*/
/*
* Checking routine: return maxrecs for the block.
*/
STATIC int /* number of records fitting in block */
xfs_btree_maxrecs(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_btree_block_t *block);/* generic btree block pointer */
/*
* Internal routines.
*/
/*
* Checking routine: return maxrecs for the block.
*/
STATIC int /* number of records fitting in block */
xfs_btree_maxrecs(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_btree_block_t *block) /* generic btree block pointer */
{
switch (cur->bc_btnum) {
case XFS_BTNUM_BNO:
case XFS_BTNUM_CNT:
return (int)XFS_ALLOC_BLOCK_MAXRECS(INT_GET(block->bb_h.bb_level, ARCH_CONVERT), cur);
case XFS_BTNUM_BMAP:
return (int)XFS_BMAP_BLOCK_IMAXRECS(INT_GET(block->bb_h.bb_level, ARCH_CONVERT), cur);
case XFS_BTNUM_INO:
return (int)XFS_INOBT_BLOCK_MAXRECS(INT_GET(block->bb_h.bb_level, ARCH_CONVERT), cur);
default:
ASSERT(0);
return 0;
}
}
/*
* External routines.
*/
#ifdef DEBUG
/*
* Debug routine: check that block header is ok.
*/
void
xfs_btree_check_block(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_btree_block_t *block, /* generic btree block pointer */
int level, /* level of the btree block */
xfs_buf_t *bp) /* buffer containing block, if any */
{
if (XFS_BTREE_LONG_PTRS(cur->bc_btnum))
xfs_btree_check_lblock(cur, (xfs_btree_lblock_t *)block, level,
bp);
else
xfs_btree_check_sblock(cur, (xfs_btree_sblock_t *)block, level,
bp);
}
/*
* Debug routine: check that keys are in the right order.
*/
void
xfs_btree_check_key(
xfs_btnum_t btnum, /* btree identifier */
void *ak1, /* pointer to left (lower) key */
void *ak2) /* pointer to right (higher) key */
{
switch (btnum) {
case XFS_BTNUM_BNO: {
xfs_alloc_key_t *k1;
xfs_alloc_key_t *k2;
k1 = ak1;
k2 = ak2;
ASSERT(INT_GET(k1->ar_startblock, ARCH_CONVERT) < INT_GET(k2->ar_startblock, ARCH_CONVERT));
break;
}
case XFS_BTNUM_CNT: {
xfs_alloc_key_t *k1;
xfs_alloc_key_t *k2;
k1 = ak1;
k2 = ak2;
ASSERT(INT_GET(k1->ar_blockcount, ARCH_CONVERT) < INT_GET(k2->ar_blockcount, ARCH_CONVERT) ||
(INT_GET(k1->ar_blockcount, ARCH_CONVERT) == INT_GET(k2->ar_blockcount, ARCH_CONVERT) &&
INT_GET(k1->ar_startblock, ARCH_CONVERT) < INT_GET(k2->ar_startblock, ARCH_CONVERT)));
break;
}
case XFS_BTNUM_BMAP: {
xfs_bmbt_key_t *k1;
xfs_bmbt_key_t *k2;
k1 = ak1;
k2 = ak2;
ASSERT(INT_GET(k1->br_startoff, ARCH_CONVERT) < INT_GET(k2->br_startoff, ARCH_CONVERT));
break;
}
case XFS_BTNUM_INO: {
xfs_inobt_key_t *k1;
xfs_inobt_key_t *k2;
k1 = ak1;
k2 = ak2;
ASSERT(INT_GET(k1->ir_startino, ARCH_CONVERT) < INT_GET(k2->ir_startino, ARCH_CONVERT));
break;
}
default:
ASSERT(0);
}
}
#endif /* DEBUG */
/*
* Checking routine: check that long form block header is ok.
*/
/* ARGSUSED */
int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_lblock(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_btree_lblock_t *block, /* btree long form block pointer */
int level, /* level of the btree block */
xfs_buf_t *bp) /* buffer for block, if any */
{
int lblock_ok; /* block passes checks */
xfs_mount_t *mp; /* file system mount point */
mp = cur->bc_mp;
lblock_ok =
INT_GET(block->bb_magic, ARCH_CONVERT) == xfs_magics[cur->bc_btnum] &&
INT_GET(block->bb_level, ARCH_CONVERT) == level &&
INT_GET(block->bb_numrecs, ARCH_CONVERT) <=
xfs_btree_maxrecs(cur, (xfs_btree_block_t *)block) &&
INT_GET(block->bb_leftsib, ARCH_CONVERT) != 0 &&
(INT_GET(block->bb_leftsib, ARCH_CONVERT) == NULLDFSBNO ||
XFS_FSB_SANITY_CHECK(mp, INT_GET(block->bb_leftsib, ARCH_CONVERT))) &&
INT_GET(block->bb_rightsib, ARCH_CONVERT) != 0 &&
(INT_GET(block->bb_rightsib, ARCH_CONVERT) == NULLDFSBNO ||
XFS_FSB_SANITY_CHECK(mp, INT_GET(block->bb_rightsib, ARCH_CONVERT)));
if (XFS_TEST_ERROR(!lblock_ok, mp, XFS_ERRTAG_BTREE_CHECK_LBLOCK,
XFS_RANDOM_BTREE_CHECK_LBLOCK)) {
if (bp)
xfs_buftrace("LBTREE ERROR", bp);
#ifdef __KERNEL__ /* additional, temporary, debugging code */
cmn_err(CE_NOTE,
"EFSCORRUPTED returned from file %s line %d",
__FILE__, __LINE__);
#endif
return XFS_ERROR(EFSCORRUPTED);
}
return 0;
}
/*
* Checking routine: check that (long) pointer is ok.
*/
int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_lptr(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_dfsbno_t ptr, /* btree block disk address */
int level) /* btree block level */
{
xfs_mount_t *mp; /* file system mount point */
mp = cur->bc_mp;
XFS_WANT_CORRUPTED_RETURN(
level > 0 &&
ptr != NULLDFSBNO &&
XFS_FSB_SANITY_CHECK(mp, ptr));
return 0;
}
#ifdef DEBUG
/*
* Debug routine: check that records are in the right order.
*/
void
xfs_btree_check_rec(
xfs_btnum_t btnum, /* btree identifier */
void *ar1, /* pointer to left (lower) record */
void *ar2) /* pointer to right (higher) record */
{
switch (btnum) {
case XFS_BTNUM_BNO: {
xfs_alloc_rec_t *r1;
xfs_alloc_rec_t *r2;
r1 = ar1;
r2 = ar2;
ASSERT(INT_GET(r1->ar_startblock, ARCH_CONVERT) + INT_GET(r1->ar_blockcount, ARCH_CONVERT) <=
INT_GET(r2->ar_startblock, ARCH_CONVERT));
break;
}
case XFS_BTNUM_CNT: {
xfs_alloc_rec_t *r1;
xfs_alloc_rec_t *r2;
r1 = ar1;
r2 = ar2;
ASSERT(INT_GET(r1->ar_blockcount, ARCH_CONVERT) < INT_GET(r2->ar_blockcount, ARCH_CONVERT) ||
(INT_GET(r1->ar_blockcount, ARCH_CONVERT) == INT_GET(r2->ar_blockcount, ARCH_CONVERT) &&
INT_GET(r1->ar_startblock, ARCH_CONVERT) < INT_GET(r2->ar_startblock, ARCH_CONVERT)));
break;
}
case XFS_BTNUM_BMAP: {
xfs_bmbt_rec_t *r1;
xfs_bmbt_rec_t *r2;
r1 = ar1;
r2 = ar2;
ASSERT(xfs_bmbt_get_startoff(r1) +
xfs_bmbt_get_blockcount(r1) <=
xfs_bmbt_get_startoff(r2));
break;
}
case XFS_BTNUM_INO: {
xfs_inobt_rec_t *r1;
xfs_inobt_rec_t *r2;
r1 = ar1;
r2 = ar2;
ASSERT(INT_GET(r1->ir_startino, ARCH_CONVERT) + XFS_INODES_PER_CHUNK <=
INT_GET(r2->ir_startino, ARCH_CONVERT));
break;
}
default:
ASSERT(0);
}
}
#endif /* DEBUG */
/*
* Checking routine: check that block header is ok.
*/
/* ARGSUSED */
int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_sblock(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_btree_sblock_t *block, /* btree short form block pointer */
int level, /* level of the btree block */
xfs_buf_t *bp) /* buffer containing block */
{
xfs_buf_t *agbp; /* buffer for ag. freespace struct */
xfs_agf_t *agf; /* ag. freespace structure */
xfs_agblock_t agflen; /* native ag. freespace length */
int sblock_ok; /* block passes checks */
agbp = cur->bc_private.a.agbp;
agf = XFS_BUF_TO_AGF(agbp);
agflen = INT_GET(agf->agf_length, ARCH_CONVERT);
sblock_ok =
INT_GET(block->bb_magic, ARCH_CONVERT) == xfs_magics[cur->bc_btnum] &&
INT_GET(block->bb_level, ARCH_CONVERT) == level &&
INT_GET(block->bb_numrecs, ARCH_CONVERT) <=
xfs_btree_maxrecs(cur, (xfs_btree_block_t *)block) &&
(INT_GET(block->bb_leftsib, ARCH_CONVERT) == NULLAGBLOCK ||
INT_GET(block->bb_leftsib, ARCH_CONVERT) < agflen) &&
INT_GET(block->bb_leftsib, ARCH_CONVERT) != 0 &&
(INT_GET(block->bb_rightsib, ARCH_CONVERT) == NULLAGBLOCK ||
INT_GET(block->bb_rightsib, ARCH_CONVERT) < agflen) &&
INT_GET(block->bb_rightsib, ARCH_CONVERT) != 0;
if (XFS_TEST_ERROR(!sblock_ok, cur->bc_mp,
XFS_ERRTAG_BTREE_CHECK_SBLOCK,
XFS_RANDOM_BTREE_CHECK_SBLOCK)) {
if (bp)
xfs_buftrace("SBTREE ERROR", bp);
#ifdef __KERNEL__ /* additional, temporary, debugging code */
cmn_err(CE_NOTE,
"xfs_btree_check_sblock: Not OK:");
cmn_err(CE_NOTE,
"magic 0x%x level %d numrecs %d leftsib %d rightsib %d",
INT_GET(block->bb_magic, ARCH_CONVERT),
INT_GET(block->bb_level, ARCH_CONVERT),
INT_GET(block->bb_numrecs, ARCH_CONVERT),
INT_GET(block->bb_leftsib, ARCH_CONVERT),
INT_GET(block->bb_rightsib, ARCH_CONVERT));
#endif
return XFS_ERROR(EFSCORRUPTED);
}
return 0;
}
/*
* Checking routine: check that (short) pointer is ok.
*/
int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_sptr(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agblock_t ptr, /* btree block disk address */
int level) /* btree block level */
{
xfs_buf_t *agbp; /* buffer for ag. freespace struct */
xfs_agf_t *agf; /* ag. freespace structure */
agbp = cur->bc_private.a.agbp;
agf = XFS_BUF_TO_AGF(agbp);
XFS_WANT_CORRUPTED_RETURN(
level > 0 &&
ptr != NULLAGBLOCK && ptr != 0 &&
ptr < INT_GET(agf->agf_length, ARCH_CONVERT));
return 0;
}
/*
* Delete the btree cursor.
*/
void
xfs_btree_del_cursor(
xfs_btree_cur_t *cur, /* btree cursor */
int error) /* del because of error */
{
int i; /* btree level */
/*
* Clear the buffer pointers, and release the buffers.
* If we're doing this in the face of an error, we
* need to make sure to inspect all of the entries
* in the bc_bufs array for buffers to be unlocked.
* This is because some of the btree code works from
* level n down to 0, and if we get an error along
* the way we won't have initialized all the entries
* down to 0.
*/
for (i = 0; i < cur->bc_nlevels; i++) {
if (cur->bc_bufs[i])
xfs_btree_setbuf(cur, i, NULL);
else if (!error)
break;
}
/*
* Can't free a bmap cursor without having dealt with the
* allocated indirect blocks' accounting.
*/
ASSERT(cur->bc_btnum != XFS_BTNUM_BMAP ||
cur->bc_private.b.allocated == 0);
/*
* Free the cursor.
*/
kmem_zone_free(xfs_btree_cur_zone, cur);
}
/*
* Duplicate the btree cursor.
* Allocate a new one, copy the record, re-get the buffers.
*/
int /* error */
xfs_btree_dup_cursor(
xfs_btree_cur_t *cur, /* input cursor */
xfs_btree_cur_t **ncur) /* output cursor */
{
xfs_buf_t *bp; /* btree block's buffer pointer */
int error; /* error return value */
int i; /* level number of btree block */
xfs_mount_t *mp; /* mount structure for filesystem */
xfs_btree_cur_t *new; /* new cursor value */
xfs_trans_t *tp; /* transaction pointer, can be NULL */
tp = cur->bc_tp;
mp = cur->bc_mp;
/*
* Allocate a new cursor like the old one.
*/
new = xfs_btree_init_cursor(mp, tp, cur->bc_private.a.agbp,
cur->bc_private.a.agno, cur->bc_btnum, cur->bc_private.b.ip,
cur->bc_private.b.whichfork);
/*
* Copy the record currently in the cursor.
*/
new->bc_rec = cur->bc_rec;
/*
* For each level current, re-get the buffer and copy the ptr value.
*/
for (i = 0; i < new->bc_nlevels; i++) {
new->bc_ptrs[i] = cur->bc_ptrs[i];
new->bc_ra[i] = cur->bc_ra[i];
if ((bp = cur->bc_bufs[i])) {
if ((error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
XFS_BUF_ADDR(bp), mp->m_bsize, 0, &bp))) {
xfs_btree_del_cursor(new, error);
*ncur = NULL;
return error;
}
new->bc_bufs[i] = bp;
ASSERT(bp);
ASSERT(!XFS_BUF_GETERROR(bp));
} else
new->bc_bufs[i] = NULL;
}
/*
* For bmap btrees, copy the firstblock, flist, and flags values,
* since init cursor doesn't get them.
*/
if (new->bc_btnum == XFS_BTNUM_BMAP) {
new->bc_private.b.firstblock = cur->bc_private.b.firstblock;
new->bc_private.b.flist = cur->bc_private.b.flist;
new->bc_private.b.flags = cur->bc_private.b.flags;
}
*ncur = new;
return 0;
}
/*
* Change the cursor to point to the first record at the given level.
* Other levels are unaffected.
*/
int /* success=1, failure=0 */
xfs_btree_firstrec(
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level to change */
{
xfs_btree_block_t *block; /* generic btree block pointer */
xfs_buf_t *bp; /* buffer containing block */
/*
* Get the block pointer for this level.
*/
block = xfs_btree_get_block(cur, level, &bp);
xfs_btree_check_block(cur, block, level, bp);
/*
* It's empty, there is no such record.
*/
if (INT_GET(block->bb_h.bb_numrecs, ARCH_CONVERT) == 0)
return 0;
/*
* Set the ptr value to 1, that's the first record/key.
*/
cur->bc_ptrs[level] = 1;
return 1;
}
/*
* Retrieve the block pointer from the cursor at the given level.
* This may be a bmap btree root or from a buffer.
*/
xfs_btree_block_t * /* generic btree block pointer */
xfs_btree_get_block(
xfs_btree_cur_t *cur, /* btree cursor */
int level, /* level in btree */
xfs_buf_t **bpp) /* buffer containing the block */
{
xfs_btree_block_t *block; /* return value */
xfs_buf_t *bp; /* return buffer */
xfs_ifork_t *ifp; /* inode fork pointer */
int whichfork; /* data or attr fork */
if (cur->bc_btnum == XFS_BTNUM_BMAP && level == cur->bc_nlevels - 1) {
whichfork = cur->bc_private.b.whichfork;
ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, whichfork);
block = (xfs_btree_block_t *)ifp->if_broot;
bp = NULL;
} else {
bp = cur->bc_bufs[level];
block = XFS_BUF_TO_BLOCK(bp);
}
ASSERT(block != NULL);
*bpp = bp;
return block;
}
/*
* Get a buffer for the block, return it with no data read.
* Long-form addressing.
*/
xfs_buf_t * /* buffer for fsbno */
xfs_btree_get_bufl(
xfs_mount_t *mp, /* file system mount point */
xfs_trans_t *tp, /* transaction pointer */
xfs_fsblock_t fsbno, /* file system block number */
uint lock) /* lock flags for get_buf */
{
xfs_buf_t *bp; /* buffer pointer (return value) */
xfs_daddr_t d; /* real disk block address */
ASSERT(fsbno != NULLFSBLOCK);
d = XFS_FSB_TO_DADDR(mp, fsbno);
bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
ASSERT(bp);
ASSERT(!XFS_BUF_GETERROR(bp));
return bp;
}
/*
* Get a buffer for the block, return it with no data read.
* Short-form addressing.
*/
xfs_buf_t * /* buffer for agno/agbno */
xfs_btree_get_bufs(
xfs_mount_t *mp, /* file system mount point */
xfs_trans_t *tp, /* transaction pointer */
xfs_agnumber_t agno, /* allocation group number */
xfs_agblock_t agbno, /* allocation group block number */
uint lock) /* lock flags for get_buf */
{
xfs_buf_t *bp; /* buffer pointer (return value) */
xfs_daddr_t d; /* real disk block address */
ASSERT(agno != NULLAGNUMBER);
ASSERT(agbno != NULLAGBLOCK);
d = XFS_AGB_TO_DADDR(mp, agno, agbno);
bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
ASSERT(bp);
ASSERT(!XFS_BUF_GETERROR(bp));
return bp;
}
/*
* Allocate a new btree cursor.
* The cursor is either for allocation (A) or bmap (B) or inodes (I).
*/
xfs_btree_cur_t * /* new btree cursor */
xfs_btree_init_cursor(
xfs_mount_t *mp, /* file system mount point */
xfs_trans_t *tp, /* transaction pointer */
xfs_buf_t *agbp, /* (A only) buffer for agf structure */
/* (I only) buffer for agi structure */
xfs_agnumber_t agno, /* (AI only) allocation group number */
xfs_btnum_t btnum, /* btree identifier */
xfs_inode_t *ip, /* (B only) inode owning the btree */
int whichfork) /* (B only) data or attr fork */
{
xfs_agf_t *agf; /* (A) allocation group freespace */
xfs_agi_t *agi; /* (I) allocation group inodespace */
xfs_btree_cur_t *cur; /* return value */
xfs_ifork_t *ifp; /* (I) inode fork pointer */
int nlevels=0; /* number of levels in the btree */
ASSERT(xfs_btree_cur_zone != NULL);
/*
* Allocate a new cursor.
*/
cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
/*
* Deduce the number of btree levels from the arguments.
*/
switch (btnum) {
case XFS_BTNUM_BNO:
case XFS_BTNUM_CNT:
agf = XFS_BUF_TO_AGF(agbp);
nlevels = INT_GET(agf->agf_levels[btnum], ARCH_CONVERT);
break;
case XFS_BTNUM_BMAP:
ifp = XFS_IFORK_PTR(ip, whichfork);
nlevels = INT_GET(ifp->if_broot->bb_level, ARCH_CONVERT) + 1;
break;
case XFS_BTNUM_INO:
agi = XFS_BUF_TO_AGI(agbp);
nlevels = INT_GET(agi->agi_level, ARCH_CONVERT);
break;
default:
ASSERT(0);
}
/*
* Fill in the common fields.
*/
cur->bc_tp = tp;
cur->bc_mp = mp;
cur->bc_nlevels = nlevels;
cur->bc_btnum = btnum;
cur->bc_blocklog = mp->m_sb.sb_blocklog;
/*
* Fill in private fields.
*/
switch (btnum) {
case XFS_BTNUM_BNO:
case XFS_BTNUM_CNT:
/*
* Allocation btree fields.
*/
cur->bc_private.a.agbp = agbp;
cur->bc_private.a.agno = agno;
break;
case XFS_BTNUM_BMAP:
/*
* Bmap btree fields.
*/
cur->bc_private.b.forksize = XFS_IFORK_SIZE(ip, whichfork);
cur->bc_private.b.ip = ip;
cur->bc_private.b.firstblock = NULLFSBLOCK;
cur->bc_private.b.flist = NULL;
cur->bc_private.b.allocated = 0;
cur->bc_private.b.flags = 0;
cur->bc_private.b.whichfork = whichfork;
break;
case XFS_BTNUM_INO:
/*
* Inode allocation btree fields.
*/
cur->bc_private.i.agbp = agbp;
cur->bc_private.i.agno = agno;
break;
default:
ASSERT(0);
}
return cur;
}
/*
* Check for the cursor referring to the last block at the given level.
*/
int /* 1=is last block, 0=not last block */
xfs_btree_islastblock(
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level to check */
{
xfs_btree_block_t *block; /* generic btree block pointer */
xfs_buf_t *bp; /* buffer containing block */
block = xfs_btree_get_block(cur, level, &bp);
xfs_btree_check_block(cur, block, level, bp);
if (XFS_BTREE_LONG_PTRS(cur->bc_btnum))
return INT_GET(block->bb_u.l.bb_rightsib, ARCH_CONVERT) == NULLDFSBNO;
else
return INT_GET(block->bb_u.s.bb_rightsib, ARCH_CONVERT) == NULLAGBLOCK;
}
/*
* Change the cursor to point to the last record in the current block
* at the given level. Other levels are unaffected.
*/
int /* success=1, failure=0 */
xfs_btree_lastrec(
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level to change */
{
xfs_btree_block_t *block; /* generic btree block pointer */
xfs_buf_t *bp; /* buffer containing block */
/*
* Get the block pointer for this level.
*/
block = xfs_btree_get_block(cur, level, &bp);
xfs_btree_check_block(cur, block, level, bp);
/*
* It's empty, there is no such record.
*/
if (INT_GET(block->bb_h.bb_numrecs, ARCH_CONVERT) == 0)
return 0;
/*
* Set the ptr value to numrecs, that's the last record/key.
*/
cur->bc_ptrs[level] = INT_GET(block->bb_h.bb_numrecs, ARCH_CONVERT);
return 1;
}
/*
* Compute first and last byte offsets for the fields given.
* Interprets the offsets table, which contains struct field offsets.
*/
void
xfs_btree_offsets(
__int64_t fields, /* bitmask of fields */
const short *offsets, /* table of field offsets */
int nbits, /* number of bits to inspect */
int *first, /* output: first byte offset */
int *last) /* output: last byte offset */
{
int i; /* current bit number */
__int64_t imask; /* mask for current bit number */
ASSERT(fields != 0);
/*
* Find the lowest bit, so the first byte offset.
*/
for (i = 0, imask = 1LL; ; i++, imask <<= 1) {
if (imask & fields) {
*first = offsets[i];
break;
}
}
/*
* Find the highest bit, so the last byte offset.
*/
for (i = nbits - 1, imask = 1LL << i; ; i--, imask >>= 1) {
if (imask & fields) {
*last = offsets[i + 1] - 1;
break;
}
}
}
/*
* Get a buffer for the block, return it read in.
* Long-form addressing.
*/
int /* error */
xfs_btree_read_bufl(
xfs_mount_t *mp, /* file system mount point */
xfs_trans_t *tp, /* transaction pointer */
xfs_fsblock_t fsbno, /* file system block number */
uint lock, /* lock flags for read_buf */
xfs_buf_t **bpp, /* buffer for fsbno */
int refval) /* ref count value for buffer */
{
xfs_buf_t *bp; /* return value */
xfs_daddr_t d; /* real disk block address */
int error;
ASSERT(fsbno != NULLFSBLOCK);
d = XFS_FSB_TO_DADDR(mp, fsbno);
if ((error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d,
mp->m_bsize, lock, &bp))) {
return error;
}
ASSERT(!bp || !XFS_BUF_GETERROR(bp));
if (bp != NULL) {
XFS_BUF_SET_VTYPE_REF(bp, B_FS_MAP, refval);
}
*bpp = bp;
return 0;
}
/*
* Get a buffer for the block, return it read in.
* Short-form addressing.
*/
int /* error */
xfs_btree_read_bufs(
xfs_mount_t *mp, /* file system mount point */
xfs_trans_t *tp, /* transaction pointer */
xfs_agnumber_t agno, /* allocation group number */
xfs_agblock_t agbno, /* allocation group block number */
uint lock, /* lock flags for read_buf */
xfs_buf_t **bpp, /* buffer for agno/agbno */
int refval) /* ref count value for buffer */
{
xfs_buf_t *bp; /* return value */
xfs_daddr_t d; /* real disk block address */
int error;
ASSERT(agno != NULLAGNUMBER);
ASSERT(agbno != NULLAGBLOCK);
d = XFS_AGB_TO_DADDR(mp, agno, agbno);
if ((error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d,
mp->m_bsize, lock, &bp))) {
return error;
}
ASSERT(!bp || !XFS_BUF_GETERROR(bp));
if (bp != NULL) {
switch (refval) {
case XFS_ALLOC_BTREE_REF:
XFS_BUF_SET_VTYPE_REF(bp, B_FS_MAP, refval);
break;
case XFS_INO_BTREE_REF:
XFS_BUF_SET_VTYPE_REF(bp, B_FS_INOMAP, refval);
break;
}
}
*bpp = bp;
return 0;
}
/*
* Read-ahead the block, don't wait for it, don't return a buffer.
* Long-form addressing.
*/
/* ARGSUSED */
void
xfs_btree_reada_bufl(
xfs_mount_t *mp, /* file system mount point */
xfs_fsblock_t fsbno, /* file system block number */
xfs_extlen_t count) /* count of filesystem blocks */
{
xfs_daddr_t d;
ASSERT(fsbno != NULLFSBLOCK);
d = XFS_FSB_TO_DADDR(mp, fsbno);
xfs_baread(mp->m_ddev_targp, d, mp->m_bsize * count);
}
/*
* Read-ahead the block, don't wait for it, don't return a buffer.
* Short-form addressing.
*/
/* ARGSUSED */
void
xfs_btree_reada_bufs(
xfs_mount_t *mp, /* file system mount point */
xfs_agnumber_t agno, /* allocation group number */
xfs_agblock_t agbno, /* allocation group block number */
xfs_extlen_t count) /* count of filesystem blocks */
{
xfs_daddr_t d;
ASSERT(agno != NULLAGNUMBER);
ASSERT(agbno != NULLAGBLOCK);
d = XFS_AGB_TO_DADDR(mp, agno, agbno);
xfs_baread(mp->m_ddev_targp, d, mp->m_bsize * count);
}
/*
* Read-ahead btree blocks, at the given level.
* Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
*/
int
xfs_btree_readahead_core(
xfs_btree_cur_t *cur, /* btree cursor */
int lev, /* level in btree */
int lr) /* left/right bits */
{
xfs_alloc_block_t *a;
xfs_bmbt_block_t *b;
xfs_inobt_block_t *i;
int rval = 0;
ASSERT(cur->bc_bufs[lev] != NULL);
cur->bc_ra[lev] |= lr;
switch (cur->bc_btnum) {
case XFS_BTNUM_BNO:
case XFS_BTNUM_CNT:
a = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[lev]);
if ((lr & XFS_BTCUR_LEFTRA) && INT_GET(a->bb_leftsib, ARCH_CONVERT) != NULLAGBLOCK) {
xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
INT_GET(a->bb_leftsib, ARCH_CONVERT), 1);
rval++;
}
if ((lr & XFS_BTCUR_RIGHTRA) && INT_GET(a->bb_rightsib, ARCH_CONVERT) != NULLAGBLOCK) {
xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
INT_GET(a->bb_rightsib, ARCH_CONVERT), 1);
rval++;
}
break;
case XFS_BTNUM_BMAP:
b = XFS_BUF_TO_BMBT_BLOCK(cur->bc_bufs[lev]);
if ((lr & XFS_BTCUR_LEFTRA) && INT_GET(b->bb_leftsib, ARCH_CONVERT) != NULLDFSBNO) {
xfs_btree_reada_bufl(cur->bc_mp, INT_GET(b->bb_leftsib, ARCH_CONVERT), 1);
rval++;
}
if ((lr & XFS_BTCUR_RIGHTRA) && INT_GET(b->bb_rightsib, ARCH_CONVERT) != NULLDFSBNO) {
xfs_btree_reada_bufl(cur->bc_mp, INT_GET(b->bb_rightsib, ARCH_CONVERT), 1);
rval++;
}
break;
case XFS_BTNUM_INO:
i = XFS_BUF_TO_INOBT_BLOCK(cur->bc_bufs[lev]);
if ((lr & XFS_BTCUR_LEFTRA) && INT_GET(i->bb_leftsib, ARCH_CONVERT) != NULLAGBLOCK) {
xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.i.agno,
INT_GET(i->bb_leftsib, ARCH_CONVERT), 1);
rval++;
}
if ((lr & XFS_BTCUR_RIGHTRA) && INT_GET(i->bb_rightsib, ARCH_CONVERT) != NULLAGBLOCK) {
xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.i.agno,
INT_GET(i->bb_rightsib, ARCH_CONVERT), 1);
rval++;
}
break;
default:
ASSERT(0);
}
return rval;
}
/*
* Set the buffer for level "lev" in the cursor to bp, releasing
* any previous buffer.
*/
void
xfs_btree_setbuf(
xfs_btree_cur_t *cur, /* btree cursor */
int lev, /* level in btree */
xfs_buf_t *bp) /* new buffer to set */
{
xfs_btree_block_t *b; /* btree block */
xfs_buf_t *obp; /* old buffer pointer */
obp = cur->bc_bufs[lev];
if (obp)
xfs_trans_brelse(cur->bc_tp, obp);
cur->bc_bufs[lev] = bp;
cur->bc_ra[lev] = 0;
if (!bp)
return;
b = XFS_BUF_TO_BLOCK(bp);
if (XFS_BTREE_LONG_PTRS(cur->bc_btnum)) {
if (INT_GET(b->bb_u.l.bb_leftsib, ARCH_CONVERT) == NULLDFSBNO)
cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
if (INT_GET(b->bb_u.l.bb_rightsib, ARCH_CONVERT) == NULLDFSBNO)
cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
} else {
if (INT_GET(b->bb_u.s.bb_leftsib, ARCH_CONVERT) == NULLAGBLOCK)
cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
if (INT_GET(b->bb_u.s.bb_rightsib, ARCH_CONVERT) == NULLAGBLOCK)
cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
}
}
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