/*
* Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms 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. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_inode_item.h"
#include "xfs_btree.h"
#include "xfs_btree_trace.h"
#include "xfs_ialloc.h"
#include "xfs_error.h"
/*
* Cursor allocation zone.
*/
kmem_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
};
/*
* External routines.
*/
#ifdef DEBUG
/*
* 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(be32_to_cpu(k1->ar_startblock) < be32_to_cpu(k2->ar_startblock));
break;
}
case XFS_BTNUM_CNT: {
xfs_alloc_key_t *k1;
xfs_alloc_key_t *k2;
k1 = ak1;
k2 = ak2;
ASSERT(be32_to_cpu(k1->ar_blockcount) < be32_to_cpu(k2->ar_blockcount) ||
(k1->ar_blockcount == k2->ar_blockcount &&
be32_to_cpu(k1->ar_startblock) < be32_to_cpu(k2->ar_startblock)));
break;
}
case XFS_BTNUM_BMAP: {
xfs_bmbt_key_t *k1;
xfs_bmbt_key_t *k2;
k1 = ak1;
k2 = ak2;
ASSERT(be64_to_cpu(k1->br_startoff) < be64_to_cpu(k2->br_startoff));
break;
}
case XFS_BTNUM_INO: {
xfs_inobt_key_t *k1;
xfs_inobt_key_t *k2;
k1 = ak1;
k2 = ak2;
ASSERT(be32_to_cpu(k1->ir_startino) < be32_to_cpu(k2->ir_startino));
break;
}
default:
ASSERT(0);
}
}
/*
* 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(be32_to_cpu(r1->ar_startblock) +
be32_to_cpu(r1->ar_blockcount) <=
be32_to_cpu(r2->ar_startblock));
break;
}
case XFS_BTNUM_CNT: {
xfs_alloc_rec_t *r1;
xfs_alloc_rec_t *r2;
r1 = ar1;
r2 = ar2;
ASSERT(be32_to_cpu(r1->ar_blockcount) < be32_to_cpu(r2->ar_blockcount) ||
(r1->ar_blockcount == r2->ar_blockcount &&
be32_to_cpu(r1->ar_startblock) < be32_to_cpu(r2->ar_startblock)));
break;
}
case XFS_BTNUM_BMAP: {
xfs_bmbt_rec_t *r1;
xfs_bmbt_rec_t *r2;
r1 = ar1;
r2 = ar2;
ASSERT(xfs_bmbt_disk_get_startoff(r1) +
xfs_bmbt_disk_get_blockcount(r1) <=
xfs_bmbt_disk_get_startoff(r2));
break;
}
case XFS_BTNUM_INO: {
xfs_inobt_rec_t *r1;
xfs_inobt_rec_t *r2;
r1 = ar1;
r2 = ar2;
ASSERT(be32_to_cpu(r1->ir_startino) + XFS_INODES_PER_CHUNK <=
be32_to_cpu(r2->ir_startino));
break;
}
default:
ASSERT(0);
}
}
#endif /* DEBUG */
int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_lblock(
struct xfs_btree_cur *cur, /* btree cursor */
struct xfs_btree_lblock *block, /* btree long form block pointer */
int level, /* level of the btree block */
struct xfs_buf *bp) /* buffer for block, if any */
{
int lblock_ok; /* block passes checks */
struct xfs_mount *mp; /* file system mount point */
mp = cur->bc_mp;
lblock_ok =
be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] &&
be16_to_cpu(block->bb_level) == level &&
be16_to_cpu(block->bb_numrecs) <=
cur->bc_ops->get_maxrecs(cur, level) &&
block->bb_leftsib &&
(be64_to_cpu(block->bb_leftsib) == NULLDFSBNO ||
XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_leftsib))) &&
block->bb_rightsib &&
(be64_to_cpu(block->bb_rightsib) == NULLDFSBNO ||
XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_rightsib)));
if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp,
XFS_ERRTAG_BTREE_CHECK_LBLOCK,
XFS_RANDOM_BTREE_CHECK_LBLOCK))) {
if (bp)
xfs_buftrace("LBTREE ERROR", bp);
XFS_ERROR_REPORT("xfs_btree_check_lblock", XFS_ERRLEVEL_LOW,
mp);
return XFS_ERROR(EFSCORRUPTED);
}
return 0;
}
int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_sblock(
struct xfs_btree_cur *cur, /* btree cursor */
struct xfs_btree_sblock *block, /* btree short form block pointer */
int level, /* level of the btree block */
struct xfs_buf *bp) /* buffer containing block */
{
struct xfs_buf *agbp; /* buffer for ag. freespace struct */
struct xfs_agf *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 = be32_to_cpu(agf->agf_length);
sblock_ok =
be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] &&
be16_to_cpu(block->bb_level) == level &&
be16_to_cpu(block->bb_numrecs) <=
cur->bc_ops->get_maxrecs(cur, level) &&
(be32_to_cpu(block->bb_leftsib) == NULLAGBLOCK ||
be32_to_cpu(block->bb_leftsib) < agflen) &&
block->bb_leftsib &&
(be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK ||
be32_to_cpu(block->bb_rightsib) < agflen) &&
block->bb_rightsib;
if (unlikely(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);
XFS_ERROR_REPORT("xfs_btree_check_sblock", XFS_ERRLEVEL_LOW,
cur->bc_mp);
return XFS_ERROR(EFSCORRUPTED);
}
return 0;
}
/*
* Debug routine: check that block header is ok.
*/
int
xfs_btree_check_block(
struct xfs_btree_cur *cur, /* btree cursor */
struct xfs_btree_block *block, /* generic btree block pointer */
int level, /* level of the btree block */
struct xfs_buf *bp) /* buffer containing block, if any */
{
if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
return xfs_btree_check_lblock(cur,
(struct xfs_btree_lblock *)block, level, bp);
} else {
return xfs_btree_check_sblock(cur,
(struct xfs_btree_sblock *)block, level, bp);
}
}
/*
* Check that (long) pointer is ok.
*/
int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_lptr(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_dfsbno_t bno, /* btree block disk address */
int level) /* btree block level */
{
XFS_WANT_CORRUPTED_RETURN(
level > 0 &&
bno != NULLDFSBNO &&
XFS_FSB_SANITY_CHECK(cur->bc_mp, bno));
return 0;
}
/*
* Check that (short) pointer is ok.
*/
int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_sptr(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agblock_t bno, /* btree block disk address */
int level) /* btree block level */
{
xfs_agblock_t agblocks = cur->bc_mp->m_sb.sb_agblocks;
XFS_WANT_CORRUPTED_RETURN(
level > 0 &&
bno != NULLAGBLOCK &&
bno != 0 &&
bno < agblocks);
return 0;
}
/*
* Check that block ptr is ok.
*/
int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_ptr(
struct xfs_btree_cur *cur, /* btree cursor */
union xfs_btree_ptr *ptr, /* btree block disk address */
int index, /* offset from ptr to check */
int level) /* btree block level */
{
if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
return xfs_btree_check_lptr(cur,
be64_to_cpu((&ptr->l)[index]), level);
} else {
return xfs_btree_check_sptr(cur,
be32_to_cpu((&ptr->s)[index]), level);
}
}
/*
* 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 = cur->bc_ops->dup_cursor(cur);
/*
* 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;
}
*ncur = new;
return 0;
}
/*
* XFS btree block layout and addressing:
*
* There are two types of blocks in the btree: leaf and non-leaf blocks.
*
* The leaf record start with a header then followed by records containing
* the values. A non-leaf block also starts with the same header, and
* then first contains lookup keys followed by an equal number of pointers
* to the btree blocks at the previous level.
*
* +--------+-------+-------+-------+-------+-------+-------+
* Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N |
* +--------+-------+-------+-------+-------+-------+-------+
*
* +--------+-------+-------+-------+-------+-------+-------+
* Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N |
* +--------+-------+-------+-------+-------+-------+-------+
*
* The header is called struct xfs_btree_block for reasons better left unknown
* and comes in different versions for short (32bit) and long (64bit) block
* pointers. The record and key structures are defined by the btree instances
* and opaque to the btree core. The block pointers are simple disk endian
* integers, available in a short (32bit) and long (64bit) variant.
*
* The helpers below calculate the offset of a given record, key or pointer
* into a btree block (xfs_btree_*_offset) or return a pointer to the given
* record, key or pointer (xfs_btree_*_addr). Note that all addressing
* inside the btree block is done using indices starting at one, not zero!
*/
/*
* Return size of the btree block header for this btree instance.
*/
static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur)
{
return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
sizeof(struct xfs_btree_lblock) :
sizeof(struct xfs_btree_sblock);
}
/*
* Return size of btree block pointers for this btree instance.
*/
static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur)
{
return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
sizeof(__be64) : sizeof(__be32);
}
/*
* Calculate offset of the n-th record in a btree block.
*/
STATIC size_t
xfs_btree_rec_offset(
struct xfs_btree_cur *cur,
int n)
{
return xfs_btree_block_len(cur) +
(n - 1) * cur->bc_ops->rec_len;
}
/*
* Calculate offset of the n-th key in a btree block.
*/
STATIC size_t
xfs_btree_key_offset(
struct xfs_btree_cur *cur,
int n)
{
return xfs_btree_block_len(cur) +
(n - 1) * cur->bc_ops->key_len;
}
/*
* Calculate offset of the n-th block pointer in a btree block.
*/
STATIC size_t
xfs_btree_ptr_offset(
struct xfs_btree_cur *cur,
int n,
int level)
{
return xfs_btree_block_len(cur) +
cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len +
(n - 1) * xfs_btree_ptr_len(cur);
}
/*
* Return a pointer to the n-th record in the btree block.
*/
STATIC union xfs_btree_rec *
xfs_btree_rec_addr(
struct xfs_btree_cur *cur,
int n,
struct xfs_btree_block *block)
{
return (union xfs_btree_rec *)
((char *)block + xfs_btree_rec_offset(cur, n));
}
/*
* Return a pointer to the n-th key in the btree block.
*/
STATIC union xfs_btree_key *
xfs_btree_key_addr(
struct xfs_btree_cur *cur,
int n,
struct xfs_btree_block *block)
{
return (union xfs_btree_key *)
((char *)block + xfs_btree_key_offset(cur, n));
}
/*
* Return a pointer to the n-th block pointer in the btree block.
*/
STATIC union xfs_btree_ptr *
xfs_btree_ptr_addr(
struct xfs_btree_cur *cur,
int n,
struct xfs_btree_block *block)
{
int level = xfs_btree_get_level(block);
ASSERT(block->bb_level != 0);
return (union xfs_btree_ptr *)
((char *)block + xfs_btree_ptr_offset(cur, n, level));
}
/*
* Get a the root block which is stored in the inode.
*
* For now this btree implementation assumes the btree root is always
* stored in the if_broot field of an inode fork.
*/
STATIC struct xfs_btree_block *
xfs_btree_get_iroot(
struct xfs_btree_cur *cur)
{
struct xfs_ifork *ifp;
ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork);
return (struct xfs_btree_block *)ifp->if_broot;
}
/*
* Retrieve the block pointer from the cursor at the given level.
* This may be an inode btree root or from a buffer.
*/
STATIC struct xfs_btree_block * /* generic btree block pointer */
xfs_btree_get_block(
struct xfs_btree_cur *cur, /* btree cursor */
int level, /* level in btree */
struct xfs_buf **bpp) /* buffer containing the block */
{
if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
(level == cur->bc_nlevels - 1)) {
*bpp = NULL;
return xfs_btree_get_iroot(cur);
}
*bpp = cur->bc_bufs[level];
return XFS_BUF_TO_BLOCK(*bpp);
}
/*
* 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;
}
/*
* 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 (cur->bc_flags & XFS_BTREE_LONG_PTRS)
return be64_to_cpu(block->bb_u.l.bb_rightsib) == NULLDFSBNO;
else
return be32_to_cpu(block->bb_u.s.bb_rightsib) == NULLAGBLOCK;
}
/*
* 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 (!block->bb_numrecs)
return 0;
/*
* Set the ptr value to 1, that's the first record/key.
*/
cur->bc_ptrs[level] = 1;
return 1;
}
/*
* 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 (!block->bb_numrecs)
return 0;
/*
* Set the ptr value to numrecs, that's the last record/key.
*/
cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs);
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);
}
STATIC int
xfs_btree_readahead_lblock(
struct xfs_btree_cur *cur,
int lr,
struct xfs_btree_block *block)
{
int rval = 0;
xfs_fsblock_t left = be64_to_cpu(block->bb_u.l.bb_leftsib);
xfs_fsblock_t right = be64_to_cpu(block->bb_u.l.bb_rightsib);
if ((lr & XFS_BTCUR_LEFTRA) && left != NULLDFSBNO) {
xfs_btree_reada_bufl(cur->bc_mp, left, 1);
rval++;
}
if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLDFSBNO) {
xfs_btree_reada_bufl(cur->bc_mp, right, 1);
rval++;
}
return rval;
}
STATIC int
xfs_btree_readahead_sblock(
struct xfs_btree_cur *cur,
int lr,
struct xfs_btree_block *block)
{
int rval = 0;
xfs_agblock_t left = be32_to_cpu(block->bb_u.s.bb_leftsib);
xfs_agblock_t right = be32_to_cpu(block->bb_u.s.bb_rightsib);
if ((lr & XFS_BTCUR_LEFTRA) && left != NULLAGBLOCK) {
xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
left, 1);
rval++;
}
if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLAGBLOCK) {
xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
right, 1);
rval++;
}
return rval;
}
/*
* Read-ahead btree blocks, at the given level.
* Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
*/
int
xfs_btree_readahead(
struct xfs_btree_cur *cur, /* btree cursor */
int lev, /* level in btree */
int lr) /* left/right bits */
{
struct xfs_btree_block *block;
/*
* No readahead needed if we are at the root level and the
* btree root is stored in the inode.
*/
if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
(lev == cur->bc_nlevels - 1))
return 0;
if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev])
return 0;
cur->bc_ra[lev] |= lr;
block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]);
if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
return xfs_btree_readahead_lblock(cur, lr, block);
return xfs_btree_readahead_sblock(cur, lr, block);
}
/*
* 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 (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
if (be64_to_cpu(b->bb_u.l.bb_leftsib) == NULLDFSBNO)
cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
if (be64_to_cpu(b->bb_u.l.bb_rightsib) == NULLDFSBNO)
cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
} else {
if (be32_to_cpu(b->bb_u.s.bb_leftsib) == NULLAGBLOCK)
cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
if (be32_to_cpu(b->bb_u.s.bb_rightsib) == NULLAGBLOCK)
cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
}
}
STATIC int
xfs_btree_ptr_is_null(
struct xfs_btree_cur *cur,
union xfs_btree_ptr *ptr)
{
if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
return be64_to_cpu(ptr->l) == NULLFSBLOCK;
else
return be32_to_cpu(ptr->s) == NULLAGBLOCK;
}
/*
* Get/set/init sibling pointers
*/
STATIC void
xfs_btree_get_sibling(
struct xfs_btree_cur *cur,
struct xfs_btree_block *block,
union xfs_btree_ptr *ptr,
int lr)
{
ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
if (lr == XFS_BB_RIGHTSIB)
ptr->l = block->bb_u.l.bb_rightsib;
else
ptr->l = block->bb_u.l.bb_leftsib;
} else {
if (lr == XFS_BB_RIGHTSIB)
ptr->s = block->bb_u.s.bb_rightsib;
else
ptr->s = block->bb_u.s.bb_leftsib;
}
}
STATIC void
xfs_btree_set_sibling(
struct xfs_btree_cur *cur,
struct xfs_btree_block *block,
union xfs_btree_ptr *ptr,
int lr)
{
ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
if (lr == XFS_BB_RIGHTSIB)
block->bb_u.l.bb_rightsib = ptr->l;
else
block->bb_u.l.bb_leftsib = ptr->l;
} else {
if (lr == XFS_BB_RIGHTSIB)
block->bb_u.s.bb_rightsib = ptr->s;
else
block->bb_u.s.bb_leftsib = ptr->s;
}
}
STATIC void
xfs_btree_init_block(
struct xfs_btree_cur *cur,
int level,
int numrecs,
struct xfs_btree_block *new) /* new block */
{
new->bb_magic = cpu_to_be32(xfs_magics[cur->bc_btnum]);
new->bb_level = cpu_to_be16(level);
new->bb_numrecs = cpu_to_be16(numrecs);
if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
new->bb_u.l.bb_leftsib = cpu_to_be64(NULLFSBLOCK);
new->bb_u.l.bb_rightsib = cpu_to_be64(NULLFSBLOCK);
} else {
new->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
new->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
}
}
/*
* Return true if ptr is the last record in the btree and
* we need to track updateѕ to this record. The decision
* will be further refined in the update_lastrec method.
*/
STATIC int
xfs_btree_is_lastrec(
struct xfs_btree_cur *cur,
struct xfs_btree_block *block,
int level)
{
union xfs_btree_ptr ptr;
if (level > 0)
return 0;
if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE))
return 0;
xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
if (!xfs_btree_ptr_is_null(cur, &ptr))
return 0;
return 1;
}
STATIC void
xfs_btree_buf_to_ptr(
struct xfs_btree_cur *cur,
struct xfs_buf *bp,
union xfs_btree_ptr *ptr)
{
if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
ptr->l = cpu_to_be64(XFS_DADDR_TO_FSB(cur->bc_mp,
XFS_BUF_ADDR(bp)));
else {
ptr->s = cpu_to_be32(XFS_DADDR_TO_AGBNO(cur->bc_mp,
XFS_BUF_ADDR(bp)));
}
}
STATIC xfs_daddr_t
xfs_btree_ptr_to_daddr(
struct xfs_btree_cur *cur,
union xfs_btree_ptr *ptr)
{
if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
ASSERT(be64_to_cpu(ptr->l) != NULLFSBLOCK);
return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l));
} else {
ASSERT(cur->bc_private.a.agno != NULLAGNUMBER);
ASSERT(be32_to_cpu(ptr->s) != NULLAGBLOCK);
return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno,
be32_to_cpu(ptr->s));
}
}
STATIC void
xfs_btree_set_refs(
struct xfs_btree_cur *cur,
struct xfs_buf *bp)
{
switch (cur->bc_btnum) {
case XFS_BTNUM_BNO:
case XFS_BTNUM_CNT:
XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_MAP, XFS_ALLOC_BTREE_REF);
break;
case XFS_BTNUM_INO:
XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_INOMAP, XFS_INO_BTREE_REF);
break;
case XFS_BTNUM_BMAP:
XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_MAP, XFS_BMAP_BTREE_REF);
break;
default:
ASSERT(0);
}
}
STATIC int
xfs_btree_get_buf_block(
struct xfs_btree_cur *cur,
union xfs_btree_ptr *ptr,
int flags,
struct xfs_btree_block **block,
struct xfs_buf **bpp)
{
struct xfs_mount *mp = cur->bc_mp;
xfs_daddr_t d;
/* need to sort out how callers deal with failures first */
ASSERT(!(flags & XFS_BUF_TRYLOCK));
d = xfs_btree_ptr_to_daddr(cur, ptr);
*bpp = xfs_trans_get_buf(cur->bc_tp, mp->m_ddev_targp, d,
mp->m_bsize, flags);
ASSERT(*bpp);
ASSERT(!XFS_BUF_GETERROR(*bpp));
*block = XFS_BUF_TO_BLOCK(*bpp);
return 0;
}
/*
* Read in the buffer at the given ptr and return the buffer and
* the block pointer within the buffer.
*/
STATIC int
xfs_btree_read_buf_block(
struct xfs_btree_cur *cur,
union xfs_btree_ptr *ptr,
int level,
int flags,
struct xfs_btree_block **block,
struct xfs_buf **bpp)
{
struct xfs_mount *mp = cur->bc_mp;
xfs_daddr_t d;
int error;
/* need to sort out how callers deal with failures first */
ASSERT(!(flags & XFS_BUF_TRYLOCK));
d = xfs_btree_ptr_to_daddr(cur, ptr);
error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d,
mp->m_bsize, flags, bpp);
if (error)
return error;
ASSERT(*bpp != NULL);
ASSERT(!XFS_BUF_GETERROR(*bpp));
xfs_btree_set_refs(cur, *bpp);
*block = XFS_BUF_TO_BLOCK(*bpp);
error = xfs_btree_check_block(cur, *block, level, *bpp);
if (error)
xfs_trans_brelse(cur->bc_tp, *bpp);
return error;
}
/*
* Copy keys from one btree block to another.
*/
STATIC void
xfs_btree_copy_keys(
struct xfs_btree_cur *cur,
union xfs_btree_key *dst_key,
union xfs_btree_key *src_key,
int numkeys)
{
ASSERT(numkeys >= 0);
memcpy(dst_key, src_key, numkeys * cur->bc_ops->key_len);
}
/*
* Copy records from one btree block to another.
*/
STATIC void
xfs_btree_copy_recs(
struct xfs_btree_cur *cur,
union xfs_btree_rec *dst_rec,
union xfs_btree_rec *src_rec,
int numrecs)
{
ASSERT(numrecs >= 0);
memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len);
}
/*
* Copy block pointers from one btree block to another.
*/
STATIC void
xfs_btree_copy_ptrs(
struct xfs_btree_cur *cur,
union xfs_btree_ptr *dst_ptr,
union xfs_btree_ptr *src_ptr,
int numptrs)
{
ASSERT(numptrs >= 0);
memcpy(dst_ptr, src_ptr, numptrs * xfs_btree_ptr_len(cur));
}
/*
* Shift keys one index left/right inside a single btree block.
*/
STATIC void
xfs_btree_shift_keys(
struct xfs_btree_cur *cur,
union xfs_btree_key *key,
int dir,
int numkeys)
{
char *dst_key;
ASSERT(numkeys >= 0);
ASSERT(dir == 1 || dir == -1);
dst_key = (char *)key + (dir * cur->bc_ops->key_len);
memmove(dst_key, key, numkeys * cur->bc_ops->key_len);
}
/*
* Shift records one index left/right inside a single btree block.
*/
STATIC void
xfs_btree_shift_recs(
struct xfs_btree_cur *cur,
union xfs_btree_rec *rec,
int dir,
int numrecs)
{
char *dst_rec;
ASSERT(numrecs >= 0);
ASSERT(dir == 1 || dir == -1);
dst_rec = (char *)rec + (dir * cur->bc_ops->rec_len);
memmove(dst_rec, rec, numrecs * cur->bc_ops->rec_len);
}
/*
* Shift block pointers one index left/right inside a single btree block.
*/
STATIC void
xfs_btree_shift_ptrs(
struct xfs_btree_cur *cur,
union xfs_btree_ptr *ptr,
int dir,
int numptrs)
{
char *dst_ptr;
ASSERT(numptrs >= 0);
ASSERT(dir == 1 || dir == -1);
dst_ptr = (char *)ptr + (dir * xfs_btree_ptr_len(cur));
memmove(dst_ptr, ptr, numptrs * xfs_btree_ptr_len(cur));
}
/*
* Log key values from the btree block.
*/
STATIC void
xfs_btree_log_keys(
struct xfs_btree_cur *cur,
struct xfs_buf *bp,
int first,
int last)
{
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
if (bp) {
xfs_trans_log_buf(cur->bc_tp, bp,
xfs_btree_key_offset(cur, first),
xfs_btree_key_offset(cur, last + 1) - 1);
} else {
xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
xfs_ilog_fbroot(cur->bc_private.b.whichfork));
}
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
}
/*
* Log record values from the btree block.
*/
STATIC void
xfs_btree_log_recs(
struct xfs_btree_cur *cur,
struct xfs_buf *bp,
int first,
int last)
{
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
xfs_trans_log_buf(cur->bc_tp, bp,
xfs_btree_rec_offset(cur, first),
xfs_btree_rec_offset(cur, last + 1) - 1);
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
}
/*
* Log block pointer fields from a btree block (nonleaf).
*/
STATIC void
xfs_btree_log_ptrs(
struct xfs_btree_cur *cur, /* btree cursor */
struct xfs_buf *bp, /* buffer containing btree block */
int first, /* index of first pointer to log */
int last) /* index of last pointer to log */
{
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
if (bp) {
struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
int level = xfs_btree_get_level(block);
xfs_trans_log_buf(cur->bc_tp, bp,
xfs_btree_ptr_offset(cur, first, level),
xfs_btree_ptr_offset(cur, last + 1, level) - 1);
} else {
xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
xfs_ilog_fbroot(cur->bc_private.b.whichfork));
}
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
}
/*
* Log fields from a btree block header.
*/
STATIC void
xfs_btree_log_block(
struct xfs_btree_cur *cur, /* btree cursor */
struct xfs_buf *bp, /* buffer containing btree block */
int fields) /* mask of fields: XFS_BB_... */
{
int first; /* first byte offset logged */
int last; /* last byte offset logged */
static const short soffsets[] = { /* table of offsets (short) */
offsetof(struct xfs_btree_sblock, bb_magic),
offsetof(struct xfs_btree_sblock, bb_level),
offsetof(struct xfs_btree_sblock, bb_numrecs),
offsetof(struct xfs_btree_sblock, bb_leftsib),
offsetof(struct xfs_btree_sblock, bb_rightsib),
sizeof(struct xfs_btree_sblock)
};
static const short loffsets[] = { /* table of offsets (long) */
offsetof(struct xfs_btree_lblock, bb_magic),
offsetof(struct xfs_btree_lblock, bb_level),
offsetof(struct xfs_btree_lblock, bb_numrecs),
offsetof(struct xfs_btree_lblock, bb_leftsib),
offsetof(struct xfs_btree_lblock, bb_rightsib),
sizeof(struct xfs_btree_lblock)
};
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGBI(cur, bp, fields);
if (bp) {
xfs_btree_offsets(fields,
(cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
loffsets : soffsets,
XFS_BB_NUM_BITS, &first, &last);
xfs_trans_log_buf(cur->bc_tp, bp, first, last);
} else {
xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
xfs_ilog_fbroot(cur->bc_private.b.whichfork));
}
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
}
/*
* Increment cursor by one record at the level.
* For nonzero levels the leaf-ward information is untouched.
*/
int /* error */
xfs_btree_increment(
struct xfs_btree_cur *cur,
int level,
int *stat) /* success/failure */
{
struct xfs_btree_block *block;
union xfs_btree_ptr ptr;
struct xfs_buf *bp;
int error; /* error return value */
int lev;
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGI(cur, level);
ASSERT(level < cur->bc_nlevels);
/* Read-ahead to the right at this level. */
xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
/* Get a pointer to the btree block. */
block = xfs_btree_get_block(cur, level, &bp);
#ifdef DEBUG
error = xfs_btree_check_block(cur, block, level, bp);
if (error)
goto error0;
#endif
/* We're done if we remain in the block after the increment. */
if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block))
goto out1;
/* Fail if we just went off the right edge of the tree. */
xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
if (xfs_btree_ptr_is_null(cur, &ptr))
goto out0;
XFS_BTREE_STATS_INC(cur, increment);
/*
* March up the tree incrementing pointers.
* Stop when we don't go off the right edge of a block.
*/
for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
block = xfs_btree_get_block(cur, lev, &bp);
#ifdef DEBUG
error = xfs_btree_check_block(cur, block, lev, bp);
if (error)
goto error0;
#endif
if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block))
break;
/* Read-ahead the right block for the next loop. */
xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
}
/*
* If we went off the root then we are either seriously
* confused or have the tree root in an inode.
*/
if (lev == cur->bc_nlevels) {
if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
goto out0;
ASSERT(0);
error = EFSCORRUPTED;
goto error0;
}
ASSERT(lev < cur->bc_nlevels);
/*
* Now walk back down the tree, fixing up the cursor's buffer
* pointers and key numbers.
*/
for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
union xfs_btree_ptr *ptrp;
ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
error = xfs_btree_read_buf_block(cur, ptrp, --lev,
0, &block, &bp);
if (error)
goto error0;
xfs_btree_setbuf(cur, lev, bp);
cur->bc_ptrs[lev] = 1;
}
out1:
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 1;
return 0;
out0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 0;
return 0;
error0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
return error;
}
/*
* Decrement cursor by one record at the level.
* For nonzero levels the leaf-ward information is untouched.
*/
int /* error */
xfs_btree_decrement(
struct xfs_btree_cur *cur,
int level,
int *stat) /* success/failure */
{
struct xfs_btree_block *block;
xfs_buf_t *bp;
int error; /* error return value */
int lev;
union xfs_btree_ptr ptr;
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGI(cur, level);
ASSERT(level < cur->bc_nlevels);
/* Read-ahead to the left at this level. */
xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA);
/* We're done if we remain in the block after the decrement. */
if (--cur->bc_ptrs[level] > 0)
goto out1;
/* Get a pointer to the btree block. */
block = xfs_btree_get_block(cur, level, &bp);
#ifdef DEBUG
error = xfs_btree_check_block(cur, block, level, bp);
if (error)
goto error0;
#endif
/* Fail if we just went off the left edge of the tree. */
xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
if (xfs_btree_ptr_is_null(cur, &ptr))
goto out0;
XFS_BTREE_STATS_INC(cur, decrement);
/*
* March up the tree decrementing pointers.
* Stop when we don't go off the left edge of a block.
*/
for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
if (--cur->bc_ptrs[lev] > 0)
break;
/* Read-ahead the left block for the next loop. */
xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA);
}
/*
* If we went off the root then we are seriously confused.
* or the root of the tree is in an inode.
*/
if (lev == cur->bc_nlevels) {
if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
goto out0;
ASSERT(0);
error = EFSCORRUPTED;
goto error0;
}
ASSERT(lev < cur->bc_nlevels);
/*
* Now walk back down the tree, fixing up the cursor's buffer
* pointers and key numbers.
*/
for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
union xfs_btree_ptr *ptrp;
ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
error = xfs_btree_read_buf_block(cur, ptrp, --lev,
0, &block, &bp);
if (error)
goto error0;
xfs_btree_setbuf(cur, lev, bp);
cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block);
}
out1:
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 1;
return 0;
out0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 0;
return 0;
error0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
return error;
}
STATIC int
xfs_btree_lookup_get_block(
struct xfs_btree_cur *cur, /* btree cursor */
int level, /* level in the btree */
union xfs_btree_ptr *pp, /* ptr to btree block */
struct xfs_btree_block **blkp) /* return btree block */
{
struct xfs_buf *bp; /* buffer pointer for btree block */
int error = 0;
/* special case the root block if in an inode */
if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
(level == cur->bc_nlevels - 1)) {
*blkp = xfs_btree_get_iroot(cur);
return 0;
}
/*
* If the old buffer at this level for the disk address we are
* looking for re-use it.
*
* Otherwise throw it away and get a new one.
*/
bp = cur->bc_bufs[level];
if (bp && XFS_BUF_ADDR(bp) == xfs_btree_ptr_to_daddr(cur, pp)) {
*blkp = XFS_BUF_TO_BLOCK(bp);
return 0;
}
error = xfs_btree_read_buf_block(cur, pp, level, 0, blkp, &bp);
if (error)
return error;
xfs_btree_setbuf(cur, level, bp);
return 0;
}
/*
* Get current search key. For level 0 we don't actually have a key
* structure so we make one up from the record. For all other levels
* we just return the right key.
*/
STATIC union xfs_btree_key *
xfs_lookup_get_search_key(
struct xfs_btree_cur *cur,
int level,
int keyno,
struct xfs_btree_block *block,
union xfs_btree_key *kp)
{
if (level == 0) {
cur->bc_ops->init_key_from_rec(kp,
xfs_btree_rec_addr(cur, keyno, block));
return kp;
}
return xfs_btree_key_addr(cur, keyno, block);
}
/*
* Lookup the record. The cursor is made to point to it, based on dir.
* Return 0 if can't find any such record, 1 for success.
*/
int /* error */
xfs_btree_lookup(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_lookup_t dir, /* <=, ==, or >= */
int *stat) /* success/failure */
{
struct xfs_btree_block *block; /* current btree block */
__int64_t diff; /* difference for the current key */
int error; /* error return value */
int keyno; /* current key number */
int level; /* level in the btree */
union xfs_btree_ptr *pp; /* ptr to btree block */
union xfs_btree_ptr ptr; /* ptr to btree block */
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGI(cur, dir);
XFS_BTREE_STATS_INC(cur, lookup);
block = NULL;
keyno = 0;
/* initialise start pointer from cursor */
cur->bc_ops->init_ptr_from_cur(cur, &ptr);
pp = &ptr;
/*
* Iterate over each level in the btree, starting at the root.
* For each level above the leaves, find the key we need, based
* on the lookup record, then follow the corresponding block
* pointer down to the next level.
*/
for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) {
/* Get the block we need to do the lookup on. */
error = xfs_btree_lookup_get_block(cur, level, pp, &block);
if (error)
goto error0;
if (diff == 0) {
/*
* If we already had a key match at a higher level, we
* know we need to use the first entry in this block.
*/
keyno = 1;
} else {
/* Otherwise search this block. Do a binary search. */
int high; /* high entry number */
int low; /* low entry number */
/* Set low and high entry numbers, 1-based. */
low = 1;
high = xfs_btree_get_numrecs(block);
if (!high) {
/* Block is empty, must be an empty leaf. */
ASSERT(level == 0 && cur->bc_nlevels == 1);
cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 0;
return 0;
}
/* Binary search the block. */
while (low <= high) {
union xfs_btree_key key;
union xfs_btree_key *kp;
XFS_BTREE_STATS_INC(cur, compare);
/* keyno is average of low and high. */
keyno = (low + high) >> 1;
/* Get current search key */
kp = xfs_lookup_get_search_key(cur, level,
keyno, block, &key);
/*
* Compute difference to get next direction:
* - less than, move right
* - greater than, move left
* - equal, we're done
*/
diff = cur->bc_ops->key_diff(cur, kp);
if (diff < 0)
low = keyno + 1;
else if (diff > 0)
high = keyno - 1;
else
break;
}
}
/*
* If there are more levels, set up for the next level
* by getting the block number and filling in the cursor.
*/
if (level > 0) {
/*
* If we moved left, need the previous key number,
* unless there isn't one.
*/
if (diff > 0 && --keyno < 1)
keyno = 1;
pp = xfs_btree_ptr_addr(cur, keyno, block);
#ifdef DEBUG
error = xfs_btree_check_ptr(cur, pp, 0, level);
if (error)
goto error0;
#endif
cur->bc_ptrs[level] = keyno;
}
}
/* Done with the search. See if we need to adjust the results. */
if (dir != XFS_LOOKUP_LE && diff < 0) {
keyno++;
/*
* If ge search and we went off the end of the block, but it's
* not the last block, we're in the wrong block.
*/
xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
if (dir == XFS_LOOKUP_GE &&
keyno > xfs_btree_get_numrecs(block) &&
!xfs_btree_ptr_is_null(cur, &ptr)) {
int i;
cur->bc_ptrs[0] = keyno;
error = xfs_btree_increment(cur, 0, &i);
if (error)
goto error0;
XFS_WANT_CORRUPTED_RETURN(i == 1);
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 1;
return 0;
}
} else if (dir == XFS_LOOKUP_LE && diff > 0)
keyno--;
cur->bc_ptrs[0] = keyno;
/* Return if we succeeded or not. */
if (keyno == 0 || keyno > xfs_btree_get_numrecs(block))
*stat = 0;
else if (dir != XFS_LOOKUP_EQ || diff == 0)
*stat = 1;
else
*stat = 0;
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
return 0;
error0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
return error;
}
/*
* Update keys at all levels from here to the root along the cursor's path.
*/
int
xfs_btree_updkey(
struct xfs_btree_cur *cur,
union xfs_btree_key *keyp,
int level)
{
struct xfs_btree_block *block;
struct xfs_buf *bp;
union xfs_btree_key *kp;
int ptr;
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGIK(cur, level, keyp);
ASSERT(!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) || level >= 1);
/*
* Go up the tree from this level toward the root.
* At each level, update the key value to the value input.
* Stop when we reach a level where the cursor isn't pointing
* at the first entry in the block.
*/
for (ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) {
#ifdef DEBUG
int error;
#endif
block = xfs_btree_get_block(cur, level, &bp);
#ifdef DEBUG
error = xfs_btree_check_block(cur, block, level, bp);
if (error) {
XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
return error;
}
#endif
ptr = cur->bc_ptrs[level];
kp = xfs_btree_key_addr(cur, ptr, block);
xfs_btree_copy_keys(cur, kp, keyp, 1);
xfs_btree_log_keys(cur, bp, ptr, ptr);
}
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
return 0;
}
/*
* Update the record referred to by cur to the value in the
* given record. This either works (return 0) or gets an
* EFSCORRUPTED error.
*/
int
xfs_btree_update(
struct xfs_btree_cur *cur,
union xfs_btree_rec *rec)
{
struct xfs_btree_block *block;
struct xfs_buf *bp;
int error;
int ptr;
union xfs_btree_rec *rp;
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGR(cur, rec);
/* Pick up the current block. */
block = xfs_btree_get_block(cur, 0, &bp);
#ifdef DEBUG
error = xfs_btree_check_block(cur, block, 0, bp);
if (error)
goto error0;
#endif
/* Get the address of the rec to be updated. */
ptr = cur->bc_ptrs[0];
rp = xfs_btree_rec_addr(cur, ptr, block);
/* Fill in the new contents and log them. */
xfs_btree_copy_recs(cur, rp, rec, 1);
xfs_btree_log_recs(cur, bp, ptr, ptr);
/*
* If we are tracking the last record in the tree and
* we are at the far right edge of the tree, update it.
*/
if (xfs_btree_is_lastrec(cur, block, 0)) {
cur->bc_ops->update_lastrec(cur, block, rec,
ptr, LASTREC_UPDATE);
}
/* Updating first rec in leaf. Pass new key value up to our parent. */
if (ptr == 1) {
union xfs_btree_key key;
cur->bc_ops->init_key_from_rec(&key, rec);
error = xfs_btree_updkey(cur, &key, 1);
if (error)
goto error0;
}
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
return 0;
error0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
return error;
}
/*
* Move 1 record left from cur/level if possible.
* Update cur to reflect the new path.
*/
int /* error */
xfs_btree_lshift(
struct xfs_btree_cur *cur,
int level,
int *stat) /* success/failure */
{
union xfs_btree_key key; /* btree key */
struct xfs_buf *lbp; /* left buffer pointer */
struct xfs_btree_block *left; /* left btree block */
int lrecs; /* left record count */
struct xfs_buf *rbp; /* right buffer pointer */
struct xfs_btree_block *right; /* right btree block */
int rrecs; /* right record count */
union xfs_btree_ptr lptr; /* left btree pointer */
union xfs_btree_key *rkp = NULL; /* right btree key */
union xfs_btree_ptr *rpp = NULL; /* right address pointer */
union xfs_btree_rec *rrp = NULL; /* right record pointer */
int error; /* error return value */
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGI(cur, level);
if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
level == cur->bc_nlevels - 1)
goto out0;
/* Set up variables for this block as "right". */
right = xfs_btree_get_block(cur, level, &rbp);
#ifdef DEBUG
error = xfs_btree_check_block(cur, right, level, rbp);
if (error)
goto error0;
#endif
/* If we've got no left sibling then we can't shift an entry left. */
xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
if (xfs_btree_ptr_is_null(cur, &lptr))
goto out0;
/*
* If the cursor entry is the one that would be moved, don't
* do it... it's too complicated.
*/
if (cur->bc_ptrs[level] <= 1)
goto out0;
/* Set up the left neighbor as "left". */
error = xfs_btree_read_buf_block(cur, &lptr, level, 0, &left, &lbp);
if (error)
goto error0;
/* If it's full, it can't take another entry. */
lrecs = xfs_btree_get_numrecs(left);
if (lrecs == cur->bc_ops->get_maxrecs(cur, level))
goto out0;
rrecs = xfs_btree_get_numrecs(right);
/*
* We add one entry to the left side and remove one for the right side.
* Accout for it here, the changes will be updated on disk and logged
* later.
*/
lrecs++;
rrecs--;
XFS_BTREE_STATS_INC(cur, lshift);
XFS_BTREE_STATS_ADD(cur, moves, 1);
/*
* If non-leaf, copy a key and a ptr to the left block.
* Log the changes to the left block.
*/
if (level > 0) {
/* It's a non-leaf. Move keys and pointers. */
union xfs_btree_key *lkp; /* left btree key */
union xfs_btree_ptr *lpp; /* left address pointer */
lkp = xfs_btree_key_addr(cur, lrecs, left);
rkp = xfs_btree_key_addr(cur, 1, right);
lpp = xfs_btree_ptr_addr(cur, lrecs, left);
rpp = xfs_btree_ptr_addr(cur, 1, right);
#ifdef DEBUG
error = xfs_btree_check_ptr(cur, rpp, 0, level);
if (error)
goto error0;
#endif
xfs_btree_copy_keys(cur, lkp, rkp, 1);
xfs_btree_copy_ptrs(cur, lpp, rpp, 1);
xfs_btree_log_keys(cur, lbp, lrecs, lrecs);
xfs_btree_log_ptrs(cur, lbp, lrecs, lrecs);
xfs_btree_check_key(cur->bc_btnum,
xfs_btree_key_addr(cur, lrecs - 1, left),
lkp);
} else {
/* It's a leaf. Move records. */
union xfs_btree_rec *lrp; /* left record pointer */
lrp = xfs_btree_rec_addr(cur, lrecs, left);
rrp = xfs_btree_rec_addr(cur, 1, right);
xfs_btree_copy_recs(cur, lrp, rrp, 1);
xfs_btree_log_recs(cur, lbp, lrecs, lrecs);
xfs_btree_check_rec(cur->bc_btnum,
xfs_btree_rec_addr(cur, lrecs - 1, left),
lrp);
}
xfs_btree_set_numrecs(left, lrecs);
xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
xfs_btree_set_numrecs(right, rrecs);
xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
/*
* Slide the contents of right down one entry.
*/
XFS_BTREE_STATS_ADD(cur, moves, rrecs - 1);
if (level > 0) {
/* It's a nonleaf. operate on keys and ptrs */
#ifdef DEBUG
int i; /* loop index */
for (i = 0; i < rrecs; i++) {
error = xfs_btree_check_ptr(cur, rpp, i + 1, level);
if (error)
goto error0;
}
#endif
xfs_btree_shift_keys(cur,
xfs_btree_key_addr(cur, 2, right),
-1, rrecs);
xfs_btree_shift_ptrs(cur,
xfs_btree_ptr_addr(cur, 2, right),
-1, rrecs);
xfs_btree_log_keys(cur, rbp, 1, rrecs);
xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
} else {
/* It's a leaf. operate on records */
xfs_btree_shift_recs(cur,
xfs_btree_rec_addr(cur, 2, right),
-1, rrecs);
xfs_btree_log_recs(cur, rbp, 1, rrecs);
/*
* If it's the first record in the block, we'll need a key
* structure to pass up to the next level (updkey).
*/
cur->bc_ops->init_key_from_rec(&key,
xfs_btree_rec_addr(cur, 1, right));
rkp = &key;
}
/* Update the parent key values of right. */
error = xfs_btree_updkey(cur, rkp, level + 1);
if (error)
goto error0;
/* Slide the cursor value left one. */
cur->bc_ptrs[level]--;
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 1;
return 0;
out0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 0;
return 0;
error0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
return error;
}
/*
* Move 1 record right from cur/level if possible.
* Update cur to reflect the new path.
*/
int /* error */
xfs_btree_rshift(
struct xfs_btree_cur *cur,
int level,
int *stat) /* success/failure */
{
union xfs_btree_key key; /* btree key */
struct xfs_buf *lbp; /* left buffer pointer */
struct xfs_btree_block *left; /* left btree block */
struct xfs_buf *rbp; /* right buffer pointer */
struct xfs_btree_block *right; /* right btree block */
struct xfs_btree_cur *tcur; /* temporary btree cursor */
union xfs_btree_ptr rptr; /* right block pointer */
union xfs_btree_key *rkp; /* right btree key */
int rrecs; /* right record count */
int lrecs; /* left record count */
int error; /* error return value */
int i; /* loop counter */
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGI(cur, level);
if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
(level == cur->bc_nlevels - 1))
goto out0;
/* Set up variables for this block as "left". */
left = xfs_btree_get_block(cur, level, &lbp);
#ifdef DEBUG
error = xfs_btree_check_block(cur, left, level, lbp);
if (error)
goto error0;
#endif
/* If we've got no right sibling then we can't shift an entry right. */
xfs_btree_get_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
if (xfs_btree_ptr_is_null(cur, &rptr))
goto out0;
/*
* If the cursor entry is the one that would be moved, don't
* do it... it's too complicated.
*/
lrecs = xfs_btree_get_numrecs(left);
if (cur->bc_ptrs[level] >= lrecs)
goto out0;
/* Set up the right neighbor as "right". */
error = xfs_btree_read_buf_block(cur, &rptr, level, 0, &right, &rbp);
if (error)
goto error0;
/* If it's full, it can't take another entry. */
rrecs = xfs_btree_get_numrecs(right);
if (rrecs == cur->bc_ops->get_maxrecs(cur, level))
goto out0;
XFS_BTREE_STATS_INC(cur, rshift);
XFS_BTREE_STATS_ADD(cur, moves, rrecs);
/*
* Make a hole at the start of the right neighbor block, then
* copy the last left block entry to the hole.
*/
if (level > 0) {
/* It's a nonleaf. make a hole in the keys and ptrs */
union xfs_btree_key *lkp;
union xfs_btree_ptr *lpp;
union xfs_btree_ptr *rpp;
lkp = xfs_btree_key_addr(cur, lrecs, left);
lpp = xfs_btree_ptr_addr(cur, lrecs, left);
rkp = xfs_btree_key_addr(cur, 1, right);
rpp = xfs_btree_ptr_addr(cur, 1, right);
#ifdef DEBUG
for (i = rrecs - 1; i >= 0; i--) {
error = xfs_btree_check_ptr(cur, rpp, i, level);
if (error)
goto error0;
}
#endif
xfs_btree_shift_keys(cur, rkp, 1, rrecs);
xfs_btree_shift_ptrs(cur, rpp, 1, rrecs);
#ifdef DEBUG
error = xfs_btree_check_ptr(cur, lpp, 0, level);
if (error)
goto error0;
#endif
/* Now put the new data in, and log it. */
xfs_btree_copy_keys(cur, rkp, lkp, 1);
xfs_btree_copy_ptrs(cur, rpp, lpp, 1);
xfs_btree_log_keys(cur, rbp, 1, rrecs + 1);
xfs_btree_log_ptrs(cur, rbp, 1, rrecs + 1);
xfs_btree_check_key(cur->bc_btnum, rkp,
xfs_btree_key_addr(cur, 2, right));
} else {
/* It's a leaf. make a hole in the records */
union xfs_btree_rec *lrp;
union xfs_btree_rec *rrp;
lrp = xfs_btree_rec_addr(cur, lrecs, left);
rrp = xfs_btree_rec_addr(cur, 1, right);
xfs_btree_shift_recs(cur, rrp, 1, rrecs);
/* Now put the new data in, and log it. */
xfs_btree_copy_recs(cur, rrp, lrp, 1);
xfs_btree_log_recs(cur, rbp, 1, rrecs + 1);
cur->bc_ops->init_key_from_rec(&key, rrp);
rkp = &key;
xfs_btree_check_rec(cur->bc_btnum, rrp,
xfs_btree_rec_addr(cur, 2, right));
}
/*
* Decrement and log left's numrecs, bump and log right's numrecs.
*/
xfs_btree_set_numrecs(left, --lrecs);
xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
xfs_btree_set_numrecs(right, ++rrecs);
xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
/*
* Using a temporary cursor, update the parent key values of the
* block on the right.
*/
error = xfs_btree_dup_cursor(cur, &tcur);
if (error)
goto error0;
i = xfs_btree_lastrec(tcur, level);
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
error = xfs_btree_increment(tcur, level, &i);
if (error)
goto error1;
error = xfs_btree_updkey(tcur, rkp, level + 1);
if (error)
goto error1;
xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 1;
return 0;
out0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 0;
return 0;
error0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
return error;
error1:
XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR);
xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
return error;
}
/*
* Split cur/level block in half.
* Return new block number and the key to its first
* record (to be inserted into parent).
*/
int /* error */
xfs_btree_split(
struct xfs_btree_cur *cur,
int level,
union xfs_btree_ptr *ptrp,
union xfs_btree_key *key,
struct xfs_btree_cur **curp,
int *stat) /* success/failure */
{
union xfs_btree_ptr lptr; /* left sibling block ptr */
struct xfs_buf *lbp; /* left buffer pointer */
struct xfs_btree_block *left; /* left btree block */
union xfs_btree_ptr rptr; /* right sibling block ptr */
struct xfs_buf *rbp; /* right buffer pointer */
struct xfs_btree_block *right; /* right btree block */
union xfs_btree_ptr rrptr; /* right-right sibling ptr */
struct xfs_buf *rrbp; /* right-right buffer pointer */
struct xfs_btree_block *rrblock; /* right-right btree block */
int lrecs;
int rrecs;
int src_index;
int error; /* error return value */
#ifdef DEBUG
int i;
#endif
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGIPK(cur, level, *ptrp, key);
XFS_BTREE_STATS_INC(cur, split);
/* Set up left block (current one). */
left = xfs_btree_get_block(cur, level, &lbp);
#ifdef DEBUG
error = xfs_btree_check_block(cur, left, level, lbp);
if (error)
goto error0;
#endif
xfs_btree_buf_to_ptr(cur, lbp, &lptr);
/* Allocate the new block. If we can't do it, we're toast. Give up. */
error = cur->bc_ops->alloc_block(cur, &lptr, &rptr, 1, stat);
if (error)
goto error0;
if (*stat == 0)
goto out0;
XFS_BTREE_STATS_INC(cur, alloc);
/* Set up the new block as "right". */
error = xfs_btree_get_buf_block(cur, &rptr, 0, &right, &rbp);
if (error)
goto error0;
/* Fill in the btree header for the new right block. */
xfs_btree_init_block(cur, xfs_btree_get_level(left), 0, right);
/*
* Split the entries between the old and the new block evenly.
* Make sure that if there's an odd number of entries now, that
* each new block will have the same number of entries.
*/
lrecs = xfs_btree_get_numrecs(left);
rrecs = lrecs / 2;
if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1)
rrecs++;
src_index = (lrecs - rrecs + 1);
XFS_BTREE_STATS_ADD(cur, moves, rrecs);
/*
* Copy btree block entries from the left block over to the
* new block, the right. Update the right block and log the
* changes.
*/
if (level > 0) {
/* It's a non-leaf. Move keys and pointers. */
union xfs_btree_key *lkp; /* left btree key */
union xfs_btree_ptr *lpp; /* left address pointer */
union xfs_btree_key *rkp; /* right btree key */
union xfs_btree_ptr *rpp; /* right address pointer */
lkp = xfs_btree_key_addr(cur, src_index, left);
lpp = xfs_btree_ptr_addr(cur, src_index, left);
rkp = xfs_btree_key_addr(cur, 1, right);
rpp = xfs_btree_ptr_addr(cur, 1, right);
#ifdef DEBUG
for (i = src_index; i < rrecs; i++) {
error = xfs_btree_check_ptr(cur, lpp, i, level);
if (error)
goto error0;
}
#endif
xfs_btree_copy_keys(cur, rkp, lkp, rrecs);
xfs_btree_copy_ptrs(cur, rpp, lpp, rrecs);
xfs_btree_log_keys(cur, rbp, 1, rrecs);
xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
/* Grab the keys to the entries moved to the right block */
xfs_btree_copy_keys(cur, key, rkp, 1);
} else {
/* It's a leaf. Move records. */
union xfs_btree_rec *lrp; /* left record pointer */
union xfs_btree_rec *rrp; /* right record pointer */
lrp = xfs_btree_rec_addr(cur, src_index, left);
rrp = xfs_btree_rec_addr(cur, 1, right);
xfs_btree_copy_recs(cur, rrp, lrp, rrecs);
xfs_btree_log_recs(cur, rbp, 1, rrecs);
cur->bc_ops->init_key_from_rec(key,
xfs_btree_rec_addr(cur, 1, right));
}
/*
* Find the left block number by looking in the buffer.
* Adjust numrecs, sibling pointers.
*/
xfs_btree_get_sibling(cur, left, &rrptr, XFS_BB_RIGHTSIB);
xfs_btree_set_sibling(cur, right, &rrptr, XFS_BB_RIGHTSIB);
xfs_btree_set_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
xfs_btree_set_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
lrecs -= rrecs;
xfs_btree_set_numrecs(left, lrecs);
xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs);
xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS);
xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
/*
* If there's a block to the new block's right, make that block
* point back to right instead of to left.
*/
if (!xfs_btree_ptr_is_null(cur, &rrptr)) {
error = xfs_btree_read_buf_block(cur, &rrptr, level,
0, &rrblock, &rrbp);
if (error)
goto error0;
xfs_btree_set_sibling(cur, rrblock, &rptr, XFS_BB_LEFTSIB);
xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
}
/*
* If the cursor is really in the right block, move it there.
* If it's just pointing past the last entry in left, then we'll
* insert there, so don't change anything in that case.
*/
if (cur->bc_ptrs[level] > lrecs + 1) {
xfs_btree_setbuf(cur, level, rbp);
cur->bc_ptrs[level] -= lrecs;
}
/*
* If there are more levels, we'll need another cursor which refers
* the right block, no matter where this cursor was.
*/
if (level + 1 < cur->bc_nlevels) {
error = xfs_btree_dup_cursor(cur, curp);
if (error)
goto error0;
(*curp)->bc_ptrs[level + 1]++;
}
*ptrp = rptr;
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 1;
return 0;
out0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 0;
return 0;
error0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
return error;
}
