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freebsd/sys/gnu/fs/xfs/xfs_alloc_btree.c
Craig Rodrigues 331b6cc0ea Sync XFS for FreeBSD tree with newer changes from SGI XFS for Linux tree. 
Improve support for writing to XFS partitions.

Work done by:	Russell Cattelan <cattelan at xfs dot org>
2006-06-09 06:04:06 +00:00

2204 lines
65 KiB
C
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/*
* Copyright (c) 2000-2001,2005 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_dir.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_dir_sf.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_alloc.h"
#include "xfs_error.h"
/*
* Prototypes for internal functions.
*/
STATIC void xfs_alloc_log_block(xfs_trans_t *, xfs_buf_t *, int);
STATIC void xfs_alloc_log_keys(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC void xfs_alloc_log_ptrs(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC void xfs_alloc_log_recs(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC int xfs_alloc_lshift(xfs_btree_cur_t *, int, int *);
STATIC int xfs_alloc_newroot(xfs_btree_cur_t *, int *);
STATIC int xfs_alloc_rshift(xfs_btree_cur_t *, int, int *);
STATIC int xfs_alloc_split(xfs_btree_cur_t *, int, xfs_agblock_t *,
xfs_alloc_key_t *, xfs_btree_cur_t **, int *);
STATIC int xfs_alloc_updkey(xfs_btree_cur_t *, xfs_alloc_key_t *, int);
/*
* Internal functions.
*/
/*
* Single level of the xfs_alloc_delete record deletion routine.
* Delete record pointed to by cur/level.
* Remove the record from its block then rebalance the tree.
* Return 0 for error, 1 for done, 2 to go on to the next level.
*/
STATIC int /* error */
xfs_alloc_delrec(
xfs_btree_cur_t *cur, /* btree cursor */
int level, /* level removing record from */
int *stat) /* fail/done/go-on */
{
xfs_agf_t *agf; /* allocation group freelist header */
xfs_alloc_block_t *block; /* btree block record/key lives in */
xfs_agblock_t bno; /* btree block number */
xfs_buf_t *bp; /* buffer for block */
int error; /* error return value */
int i; /* loop index */
xfs_alloc_key_t key; /* kp points here if block is level 0 */
xfs_agblock_t lbno; /* left block's block number */
xfs_buf_t *lbp; /* left block's buffer pointer */
xfs_alloc_block_t *left; /* left btree block */
xfs_alloc_key_t *lkp=NULL; /* left block key pointer */
xfs_alloc_ptr_t *lpp=NULL; /* left block address pointer */
int lrecs=0; /* number of records in left block */
xfs_alloc_rec_t *lrp; /* left block record pointer */
xfs_mount_t *mp; /* mount structure */
int ptr; /* index in btree block for this rec */
xfs_agblock_t rbno; /* right block's block number */
xfs_buf_t *rbp; /* right block's buffer pointer */
xfs_alloc_block_t *right; /* right btree block */
xfs_alloc_key_t *rkp; /* right block key pointer */
xfs_alloc_ptr_t *rpp; /* right block address pointer */
int rrecs=0; /* number of records in right block */
xfs_alloc_rec_t *rrp; /* right block record pointer */
xfs_btree_cur_t *tcur; /* temporary btree cursor */
/*
* Get the index of the entry being deleted, check for nothing there.
*/
ptr = cur->bc_ptrs[level];
if (ptr == 0) {
*stat = 0;
return 0;
}
/*
* Get the buffer & block containing the record or key/ptr.
*/
bp = cur->bc_bufs[level];
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, block, level, bp)))
return error;
#endif
/*
* Fail if we're off the end of the block.
*/
if (ptr > be16_to_cpu(block->bb_numrecs)) {
*stat = 0;
return 0;
}
XFS_STATS_INC(xs_abt_delrec);
/*
* It's a nonleaf. Excise the key and ptr being deleted, by
* sliding the entries past them down one.
* Log the changed areas of the block.
*/
if (level > 0) {
lkp = XFS_ALLOC_KEY_ADDR(block, 1, cur);
lpp = XFS_ALLOC_PTR_ADDR(block, 1, cur);
#ifdef DEBUG
for (i = ptr; i < be16_to_cpu(block->bb_numrecs); i++) {
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(lpp[i]), level)))
return error;
}
#endif
if (ptr < be16_to_cpu(block->bb_numrecs)) {
memmove(&lkp[ptr - 1], &lkp[ptr],
(be16_to_cpu(block->bb_numrecs) - ptr) * sizeof(*lkp));
memmove(&lpp[ptr - 1], &lpp[ptr],
(be16_to_cpu(block->bb_numrecs) - ptr) * sizeof(*lpp));
xfs_alloc_log_ptrs(cur, bp, ptr, be16_to_cpu(block->bb_numrecs) - 1);
xfs_alloc_log_keys(cur, bp, ptr, be16_to_cpu(block->bb_numrecs) - 1);
}
}
/*
* It's a leaf. Excise the record being deleted, by sliding the
* entries past it down one. Log the changed areas of the block.
*/
else {
lrp = XFS_ALLOC_REC_ADDR(block, 1, cur);
if (ptr < be16_to_cpu(block->bb_numrecs)) {
memmove(&lrp[ptr - 1], &lrp[ptr],
(be16_to_cpu(block->bb_numrecs) - ptr) * sizeof(*lrp));
xfs_alloc_log_recs(cur, bp, ptr, be16_to_cpu(block->bb_numrecs) - 1);
}
/*
* If it's the first record in the block, we'll need a key
* structure to pass up to the next level (updkey).
*/
if (ptr == 1) {
key.ar_startblock = lrp->ar_startblock;
key.ar_blockcount = lrp->ar_blockcount;
lkp = &key;
}
}
/*
* Decrement and log the number of entries in the block.
*/
be16_add(&block->bb_numrecs, -1);
xfs_alloc_log_block(cur->bc_tp, bp, XFS_BB_NUMRECS);
/*
* See if the longest free extent in the allocation group was
* changed by this operation. True if it's the by-size btree, and
* this is the leaf level, and there is no right sibling block,
* and this was the last record.
*/
agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
mp = cur->bc_mp;
if (level == 0 &&
cur->bc_btnum == XFS_BTNUM_CNT &&
be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK &&
ptr > be16_to_cpu(block->bb_numrecs)) {
ASSERT(ptr == be16_to_cpu(block->bb_numrecs) + 1);
/*
* There are still records in the block. Grab the size
* from the last one.
*/
if (be16_to_cpu(block->bb_numrecs)) {
rrp = XFS_ALLOC_REC_ADDR(block, be16_to_cpu(block->bb_numrecs), cur);
agf->agf_longest = rrp->ar_blockcount;
}
/*
* No free extents left.
*/
else
agf->agf_longest = 0;
mp->m_perag[be32_to_cpu(agf->agf_seqno)].pagf_longest =
be32_to_cpu(agf->agf_longest);
xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp,
XFS_AGF_LONGEST);
}
/*
* Is this the root level? If so, we're almost done.
*/
if (level == cur->bc_nlevels - 1) {
/*
* If this is the root level,
* and there's only one entry left,
* and it's NOT the leaf level,
* then we can get rid of this level.
*/
if (be16_to_cpu(block->bb_numrecs) == 1 && level > 0) {
/*
* lpp is still set to the first pointer in the block.
* Make it the new root of the btree.
*/
bno = be32_to_cpu(agf->agf_roots[cur->bc_btnum]);
agf->agf_roots[cur->bc_btnum] = *lpp;
be32_add(&agf->agf_levels[cur->bc_btnum], -1);
mp->m_perag[be32_to_cpu(agf->agf_seqno)].pagf_levels[cur->bc_btnum]--;
/*
* Put this buffer/block on the ag's freelist.
*/
if ((error = xfs_alloc_put_freelist(cur->bc_tp,
cur->bc_private.a.agbp, NULL, bno)))
return error;
/*
* Since blocks move to the free list without the
* coordination used in xfs_bmap_finish, we can't allow
* block to be available for reallocation and
* non-transaction writing (user data) until we know
* that the transaction that moved it to the free list
* is permanently on disk. We track the blocks by
* declaring these blocks as "busy"; the busy list is
* maintained on a per-ag basis and each transaction
* records which entries should be removed when the
* iclog commits to disk. If a busy block is
* allocated, the iclog is pushed up to the LSN
* that freed the block.
*/
xfs_alloc_mark_busy(cur->bc_tp,
be32_to_cpu(agf->agf_seqno), bno, 1);
xfs_trans_agbtree_delta(cur->bc_tp, -1);
xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp,
XFS_AGF_ROOTS | XFS_AGF_LEVELS);
/*
* Update the cursor so there's one fewer level.
*/
xfs_btree_setbuf(cur, level, NULL);
cur->bc_nlevels--;
} else if (level > 0 &&
(error = xfs_alloc_decrement(cur, level, &i)))
return error;
*stat = 1;
return 0;
}
/*
* If we deleted the leftmost entry in the block, update the
* key values above us in the tree.
*/
if (ptr == 1 && (error = xfs_alloc_updkey(cur, lkp, level + 1)))
return error;
/*
* If the number of records remaining in the block is at least
* the minimum, we're done.
*/
if (be16_to_cpu(block->bb_numrecs) >= XFS_ALLOC_BLOCK_MINRECS(level, cur)) {
if (level > 0 && (error = xfs_alloc_decrement(cur, level, &i)))
return error;
*stat = 1;
return 0;
}
/*
* Otherwise, we have to move some records around to keep the
* tree balanced. Look at the left and right sibling blocks to
* see if we can re-balance by moving only one record.
*/
rbno = be32_to_cpu(block->bb_rightsib);
lbno = be32_to_cpu(block->bb_leftsib);
bno = NULLAGBLOCK;
ASSERT(rbno != NULLAGBLOCK || lbno != NULLAGBLOCK);
/*
* Duplicate the cursor so our btree manipulations here won't
* disrupt the next level up.
*/
if ((error = xfs_btree_dup_cursor(cur, &tcur)))
return error;
/*
* If there's a right sibling, see if it's ok to shift an entry
* out of it.
*/
if (rbno != NULLAGBLOCK) {
/*
* Move the temp cursor to the last entry in the next block.
* Actually any entry but the first would suffice.
*/
i = xfs_btree_lastrec(tcur, level);
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
if ((error = xfs_alloc_increment(tcur, level, &i)))
goto error0;
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
i = xfs_btree_lastrec(tcur, level);
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
/*
* Grab a pointer to the block.
*/
rbp = tcur->bc_bufs[level];
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, right, level, rbp)))
goto error0;
#endif
/*
* Grab the current block number, for future use.
*/
bno = be32_to_cpu(right->bb_leftsib);
/*
* If right block is full enough so that removing one entry
* won't make it too empty, and left-shifting an entry out
* of right to us works, we're done.
*/
if (be16_to_cpu(right->bb_numrecs) - 1 >=
XFS_ALLOC_BLOCK_MINRECS(level, cur)) {
if ((error = xfs_alloc_lshift(tcur, level, &i)))
goto error0;
if (i) {
ASSERT(be16_to_cpu(block->bb_numrecs) >=
XFS_ALLOC_BLOCK_MINRECS(level, cur));
xfs_btree_del_cursor(tcur,
XFS_BTREE_NOERROR);
if (level > 0 &&
(error = xfs_alloc_decrement(cur, level,
&i)))
return error;
*stat = 1;
return 0;
}
}
/*
* Otherwise, grab the number of records in right for
* future reference, and fix up the temp cursor to point
* to our block again (last record).
*/
rrecs = be16_to_cpu(right->bb_numrecs);
if (lbno != NULLAGBLOCK) {
i = xfs_btree_firstrec(tcur, level);
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
if ((error = xfs_alloc_decrement(tcur, level, &i)))
goto error0;
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
}
}
/*
* If there's a left sibling, see if it's ok to shift an entry
* out of it.
*/
if (lbno != NULLAGBLOCK) {
/*
* Move the temp cursor to the first entry in the
* previous block.
*/
i = xfs_btree_firstrec(tcur, level);
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
if ((error = xfs_alloc_decrement(tcur, level, &i)))
goto error0;
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
xfs_btree_firstrec(tcur, level);
/*
* Grab a pointer to the block.
*/
lbp = tcur->bc_bufs[level];
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
goto error0;
#endif
/*
* Grab the current block number, for future use.
*/
bno = be32_to_cpu(left->bb_rightsib);
/*
* If left block is full enough so that removing one entry
* won't make it too empty, and right-shifting an entry out
* of left to us works, we're done.
*/
if (be16_to_cpu(left->bb_numrecs) - 1 >=
XFS_ALLOC_BLOCK_MINRECS(level, cur)) {
if ((error = xfs_alloc_rshift(tcur, level, &i)))
goto error0;
if (i) {
ASSERT(be16_to_cpu(block->bb_numrecs) >=
XFS_ALLOC_BLOCK_MINRECS(level, cur));
xfs_btree_del_cursor(tcur,
XFS_BTREE_NOERROR);
if (level == 0)
cur->bc_ptrs[0]++;
*stat = 1;
return 0;
}
}
/*
* Otherwise, grab the number of records in right for
* future reference.
*/
lrecs = be16_to_cpu(left->bb_numrecs);
}
/*
* Delete the temp cursor, we're done with it.
*/
xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
/*
* If here, we need to do a join to keep the tree balanced.
*/
ASSERT(bno != NULLAGBLOCK);
/*
* See if we can join with the left neighbor block.
*/
if (lbno != NULLAGBLOCK &&
lrecs + be16_to_cpu(block->bb_numrecs) <= XFS_ALLOC_BLOCK_MAXRECS(level, cur)) {
/*
* Set "right" to be the starting block,
* "left" to be the left neighbor.
*/
rbno = bno;
right = block;
rbp = bp;
if ((error = xfs_btree_read_bufs(mp, cur->bc_tp,
cur->bc_private.a.agno, lbno, 0, &lbp,
XFS_ALLOC_BTREE_REF)))
return error;
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
return error;
}
/*
* If that won't work, see if we can join with the right neighbor block.
*/
else if (rbno != NULLAGBLOCK &&
rrecs + be16_to_cpu(block->bb_numrecs) <=
XFS_ALLOC_BLOCK_MAXRECS(level, cur)) {
/*
* Set "left" to be the starting block,
* "right" to be the right neighbor.
*/
lbno = bno;
left = block;
lbp = bp;
if ((error = xfs_btree_read_bufs(mp, cur->bc_tp,
cur->bc_private.a.agno, rbno, 0, &rbp,
XFS_ALLOC_BTREE_REF)))
return error;
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
if ((error = xfs_btree_check_sblock(cur, right, level, rbp)))
return error;
}
/*
* Otherwise, we can't fix the imbalance.
* Just return. This is probably a logic error, but it's not fatal.
*/
else {
if (level > 0 && (error = xfs_alloc_decrement(cur, level, &i)))
return error;
*stat = 1;
return 0;
}
/*
* We're now going to join "left" and "right" by moving all the stuff
* in "right" to "left" and deleting "right".
*/
if (level > 0) {
/*
* It's a non-leaf. Move keys and pointers.
*/
lkp = XFS_ALLOC_KEY_ADDR(left, be16_to_cpu(left->bb_numrecs) + 1, cur);
lpp = XFS_ALLOC_PTR_ADDR(left, be16_to_cpu(left->bb_numrecs) + 1, cur);
rkp = XFS_ALLOC_KEY_ADDR(right, 1, cur);
rpp = XFS_ALLOC_PTR_ADDR(right, 1, cur);
#ifdef DEBUG
for (i = 0; i < be16_to_cpu(right->bb_numrecs); i++) {
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(rpp[i]), level)))
return error;
}
#endif
memcpy(lkp, rkp, be16_to_cpu(right->bb_numrecs) * sizeof(*lkp));
memcpy(lpp, rpp, be16_to_cpu(right->bb_numrecs) * sizeof(*lpp));
xfs_alloc_log_keys(cur, lbp, be16_to_cpu(left->bb_numrecs) + 1,
be16_to_cpu(left->bb_numrecs) +
be16_to_cpu(right->bb_numrecs));
xfs_alloc_log_ptrs(cur, lbp, be16_to_cpu(left->bb_numrecs) + 1,
be16_to_cpu(left->bb_numrecs) +
be16_to_cpu(right->bb_numrecs));
} else {
/*
* It's a leaf. Move records.
*/
lrp = XFS_ALLOC_REC_ADDR(left, be16_to_cpu(left->bb_numrecs) + 1, cur);
rrp = XFS_ALLOC_REC_ADDR(right, 1, cur);
memcpy(lrp, rrp, be16_to_cpu(right->bb_numrecs) * sizeof(*lrp));
xfs_alloc_log_recs(cur, lbp, be16_to_cpu(left->bb_numrecs) + 1,
be16_to_cpu(left->bb_numrecs) +
be16_to_cpu(right->bb_numrecs));
}
/*
* If we joined with the left neighbor, set the buffer in the
* cursor to the left block, and fix up the index.
*/
if (bp != lbp) {
xfs_btree_setbuf(cur, level, lbp);
cur->bc_ptrs[level] += be16_to_cpu(left->bb_numrecs);
}
/*
* If we joined with the right neighbor and there's a level above
* us, increment the cursor at that level.
*/
else if (level + 1 < cur->bc_nlevels &&
(error = xfs_alloc_increment(cur, level + 1, &i)))
return error;
/*
* Fix up the number of records in the surviving block.
*/
be16_add(&left->bb_numrecs, be16_to_cpu(right->bb_numrecs));
/*
* Fix up the right block pointer in the surviving block, and log it.
*/
left->bb_rightsib = right->bb_rightsib;
xfs_alloc_log_block(cur->bc_tp, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
/*
* If there is a right sibling now, make it point to the
* remaining block.
*/
if (be32_to_cpu(left->bb_rightsib) != NULLAGBLOCK) {
xfs_alloc_block_t *rrblock;
xfs_buf_t *rrbp;
if ((error = xfs_btree_read_bufs(mp, cur->bc_tp,
cur->bc_private.a.agno, be32_to_cpu(left->bb_rightsib), 0,
&rrbp, XFS_ALLOC_BTREE_REF)))
return error;
rrblock = XFS_BUF_TO_ALLOC_BLOCK(rrbp);
if ((error = xfs_btree_check_sblock(cur, rrblock, level, rrbp)))
return error;
rrblock->bb_leftsib = cpu_to_be32(lbno);
xfs_alloc_log_block(cur->bc_tp, rrbp, XFS_BB_LEFTSIB);
}
/*
* Free the deleting block by putting it on the freelist.
*/
if ((error = xfs_alloc_put_freelist(cur->bc_tp, cur->bc_private.a.agbp,
NULL, rbno)))
return error;
/*
* Since blocks move to the free list without the coordination
* used in xfs_bmap_finish, we can't allow block to be available
* for reallocation and non-transaction writing (user data)
* until we know that the transaction that moved it to the free
* list is permanently on disk. We track the blocks by declaring
* these blocks as "busy"; the busy list is maintained on a
* per-ag basis and each transaction records which entries
* should be removed when the iclog commits to disk. If a
* busy block is allocated, the iclog is pushed up to the
* LSN that freed the block.
*/
xfs_alloc_mark_busy(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1);
xfs_trans_agbtree_delta(cur->bc_tp, -1);
/*
* Adjust the current level's cursor so that we're left referring
* to the right node, after we're done.
* If this leaves the ptr value 0 our caller will fix it up.
*/
if (level > 0)
cur->bc_ptrs[level]--;
/*
* Return value means the next level up has something to do.
*/
*stat = 2;
return 0;
error0:
xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
return error;
}
/*
* Insert one record/level. Return information to the caller
* allowing the next level up to proceed if necessary.
*/
STATIC int /* error */
xfs_alloc_insrec(
xfs_btree_cur_t *cur, /* btree cursor */
int level, /* level to insert record at */
xfs_agblock_t *bnop, /* i/o: block number inserted */
xfs_alloc_rec_t *recp, /* i/o: record data inserted */
xfs_btree_cur_t **curp, /* output: new cursor replacing cur */
int *stat) /* output: success/failure */
{
xfs_agf_t *agf; /* allocation group freelist header */
xfs_alloc_block_t *block; /* btree block record/key lives in */
xfs_buf_t *bp; /* buffer for block */
int error; /* error return value */
int i; /* loop index */
xfs_alloc_key_t key; /* key value being inserted */
xfs_alloc_key_t *kp; /* pointer to btree keys */
xfs_agblock_t nbno; /* block number of allocated block */
xfs_btree_cur_t *ncur; /* new cursor to be used at next lvl */
xfs_alloc_key_t nkey; /* new key value, from split */
xfs_alloc_rec_t nrec; /* new record value, for caller */
int optr; /* old ptr value */
xfs_alloc_ptr_t *pp; /* pointer to btree addresses */
int ptr; /* index in btree block for this rec */
xfs_alloc_rec_t *rp; /* pointer to btree records */
ASSERT(be32_to_cpu(recp->ar_blockcount) > 0);
/*
* GCC doesn't understand the (arguably complex) control flow in
* this function and complains about uninitialized structure fields
* without this.
*/
memset(&nrec, 0, sizeof(nrec));
/*
* If we made it to the root level, allocate a new root block
* and we're done.
*/
if (level >= cur->bc_nlevels) {
XFS_STATS_INC(xs_abt_insrec);
if ((error = xfs_alloc_newroot(cur, &i)))
return error;
*bnop = NULLAGBLOCK;
*stat = i;
return 0;
}
/*
* Make a key out of the record data to be inserted, and save it.
*/
key.ar_startblock = recp->ar_startblock;
key.ar_blockcount = recp->ar_blockcount;
optr = ptr = cur->bc_ptrs[level];
/*
* If we're off the left edge, return failure.
*/
if (ptr == 0) {
*stat = 0;
return 0;
}
XFS_STATS_INC(xs_abt_insrec);
/*
* Get pointers to the btree buffer and block.
*/
bp = cur->bc_bufs[level];
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, block, level, bp)))
return error;
/*
* Check that the new entry is being inserted in the right place.
*/
if (ptr <= be16_to_cpu(block->bb_numrecs)) {
if (level == 0) {
rp = XFS_ALLOC_REC_ADDR(block, ptr, cur);
xfs_btree_check_rec(cur->bc_btnum, recp, rp);
} else {
kp = XFS_ALLOC_KEY_ADDR(block, ptr, cur);
xfs_btree_check_key(cur->bc_btnum, &key, kp);
}
}
#endif
nbno = NULLAGBLOCK;
ncur = (xfs_btree_cur_t *)0;
/*
* If the block is full, we can't insert the new entry until we
* make the block un-full.
*/
if (be16_to_cpu(block->bb_numrecs) == XFS_ALLOC_BLOCK_MAXRECS(level, cur)) {
/*
* First, try shifting an entry to the right neighbor.
*/
if ((error = xfs_alloc_rshift(cur, level, &i)))
return error;
if (i) {
/* nothing */
}
/*
* Next, try shifting an entry to the left neighbor.
*/
else {
if ((error = xfs_alloc_lshift(cur, level, &i)))
return error;
if (i)
optr = ptr = cur->bc_ptrs[level];
else {
/*
* Next, try splitting the current block in
* half. If this works we have to re-set our
* variables because we could be in a
* different block now.
*/
if ((error = xfs_alloc_split(cur, level, &nbno,
&nkey, &ncur, &i)))
return error;
if (i) {
bp = cur->bc_bufs[level];
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
#ifdef DEBUG
if ((error =
xfs_btree_check_sblock(cur,
block, level, bp)))
return error;
#endif
ptr = cur->bc_ptrs[level];
nrec.ar_startblock = nkey.ar_startblock;
nrec.ar_blockcount = nkey.ar_blockcount;
}
/*
* Otherwise the insert fails.
*/
else {
*stat = 0;
return 0;
}
}
}
}
/*
* At this point we know there's room for our new entry in the block
* we're pointing at.
*/
if (level > 0) {
/*
* It's a non-leaf entry. Make a hole for the new data
* in the key and ptr regions of the block.
*/
kp = XFS_ALLOC_KEY_ADDR(block, 1, cur);
pp = XFS_ALLOC_PTR_ADDR(block, 1, cur);
#ifdef DEBUG
for (i = be16_to_cpu(block->bb_numrecs); i >= ptr; i--) {
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(pp[i - 1]), level)))
return error;
}
#endif
memmove(&kp[ptr], &kp[ptr - 1],
(be16_to_cpu(block->bb_numrecs) - ptr + 1) * sizeof(*kp));
memmove(&pp[ptr], &pp[ptr - 1],
(be16_to_cpu(block->bb_numrecs) - ptr + 1) * sizeof(*pp));
#ifdef DEBUG
if ((error = xfs_btree_check_sptr(cur, *bnop, level)))
return error;
#endif
/*
* Now stuff the new data in, bump numrecs and log the new data.
*/
kp[ptr - 1] = key;
pp[ptr - 1] = cpu_to_be32(*bnop);
be16_add(&block->bb_numrecs, 1);
xfs_alloc_log_keys(cur, bp, ptr, be16_to_cpu(block->bb_numrecs));
xfs_alloc_log_ptrs(cur, bp, ptr, be16_to_cpu(block->bb_numrecs));
#ifdef DEBUG
if (ptr < be16_to_cpu(block->bb_numrecs))
xfs_btree_check_key(cur->bc_btnum, kp + ptr - 1,
kp + ptr);
#endif
} else {
/*
* It's a leaf entry. Make a hole for the new record.
*/
rp = XFS_ALLOC_REC_ADDR(block, 1, cur);
memmove(&rp[ptr], &rp[ptr - 1],
(be16_to_cpu(block->bb_numrecs) - ptr + 1) * sizeof(*rp));
/*
* Now stuff the new record in, bump numrecs
* and log the new data.
*/
rp[ptr - 1] = *recp; /* INT_: struct copy */
be16_add(&block->bb_numrecs, 1);
xfs_alloc_log_recs(cur, bp, ptr, be16_to_cpu(block->bb_numrecs));
#ifdef DEBUG
if (ptr < be16_to_cpu(block->bb_numrecs))
xfs_btree_check_rec(cur->bc_btnum, rp + ptr - 1,
rp + ptr);
#endif
}
/*
* Log the new number of records in the btree header.
*/
xfs_alloc_log_block(cur->bc_tp, bp, XFS_BB_NUMRECS);
/*
* If we inserted at the start of a block, update the parents' keys.
*/
if (optr == 1 && (error = xfs_alloc_updkey(cur, &key, level + 1)))
return error;
/*
* Look to see if the longest extent in the allocation group
* needs to be updated.
*/
agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
if (level == 0 &&
cur->bc_btnum == XFS_BTNUM_CNT &&
be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK &&
be32_to_cpu(recp->ar_blockcount) > be32_to_cpu(agf->agf_longest)) {
/*
* If this is a leaf in the by-size btree and there
* is no right sibling block and this block is bigger
* than the previous longest block, update it.
*/
agf->agf_longest = recp->ar_blockcount;
cur->bc_mp->m_perag[be32_to_cpu(agf->agf_seqno)].pagf_longest
= be32_to_cpu(recp->ar_blockcount);
xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp,
XFS_AGF_LONGEST);
}
/*
* Return the new block number, if any.
* If there is one, give back a record value and a cursor too.
*/
*bnop = nbno;
if (nbno != NULLAGBLOCK) {
*recp = nrec; /* INT_: struct copy */
*curp = ncur; /* INT_: struct copy */
}
*stat = 1;
return 0;
}
/*
* Log header fields from a btree block.
*/
STATIC void
xfs_alloc_log_block(
xfs_trans_t *tp, /* transaction pointer */
xfs_buf_t *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 offsets[] = { /* table of offsets */
offsetof(xfs_alloc_block_t, bb_magic),
offsetof(xfs_alloc_block_t, bb_level),
offsetof(xfs_alloc_block_t, bb_numrecs),
offsetof(xfs_alloc_block_t, bb_leftsib),
offsetof(xfs_alloc_block_t, bb_rightsib),
sizeof(xfs_alloc_block_t)
};
xfs_btree_offsets(fields, offsets, XFS_BB_NUM_BITS, &first, &last);
xfs_trans_log_buf(tp, bp, first, last);
}
/*
* Log keys from a btree block (nonleaf).
*/
STATIC void
xfs_alloc_log_keys(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_buf_t *bp, /* buffer containing btree block */
int kfirst, /* index of first key to log */
int klast) /* index of last key to log */
{
xfs_alloc_block_t *block; /* btree block to log from */
int first; /* first byte offset logged */
xfs_alloc_key_t *kp; /* key pointer in btree block */
int last; /* last byte offset logged */
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
kp = XFS_ALLOC_KEY_ADDR(block, 1, cur);
first = (int)((xfs_caddr_t)&kp[kfirst - 1] - (xfs_caddr_t)block);
last = (int)(((xfs_caddr_t)&kp[klast] - 1) - (xfs_caddr_t)block);
xfs_trans_log_buf(cur->bc_tp, bp, first, last);
}
/*
* Log block pointer fields from a btree block (nonleaf).
*/
STATIC void
xfs_alloc_log_ptrs(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_buf_t *bp, /* buffer containing btree block */
int pfirst, /* index of first pointer to log */
int plast) /* index of last pointer to log */
{
xfs_alloc_block_t *block; /* btree block to log from */
int first; /* first byte offset logged */
int last; /* last byte offset logged */
xfs_alloc_ptr_t *pp; /* block-pointer pointer in btree blk */
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
pp = XFS_ALLOC_PTR_ADDR(block, 1, cur);
first = (int)((xfs_caddr_t)&pp[pfirst - 1] - (xfs_caddr_t)block);
last = (int)(((xfs_caddr_t)&pp[plast] - 1) - (xfs_caddr_t)block);
xfs_trans_log_buf(cur->bc_tp, bp, first, last);
}
/*
* Log records from a btree block (leaf).
*/
STATIC void
xfs_alloc_log_recs(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_buf_t *bp, /* buffer containing btree block */
int rfirst, /* index of first record to log */
int rlast) /* index of last record to log */
{
xfs_alloc_block_t *block; /* btree block to log from */
int first; /* first byte offset logged */
int last; /* last byte offset logged */
xfs_alloc_rec_t *rp; /* record pointer for btree block */
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
rp = XFS_ALLOC_REC_ADDR(block, 1, cur);
#ifdef DEBUG
{
xfs_agf_t *agf;
xfs_alloc_rec_t *p;
agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
for (p = &rp[rfirst - 1]; p <= &rp[rlast - 1]; p++)
ASSERT(be32_to_cpu(p->ar_startblock) +
be32_to_cpu(p->ar_blockcount) <=
be32_to_cpu(agf->agf_length));
}
#endif
first = (int)((xfs_caddr_t)&rp[rfirst - 1] - (xfs_caddr_t)block);
last = (int)(((xfs_caddr_t)&rp[rlast] - 1) - (xfs_caddr_t)block);
xfs_trans_log_buf(cur->bc_tp, bp, first, last);
}
/*
* 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.
*/
STATIC int /* error */
xfs_alloc_lookup(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_lookup_t dir, /* <=, ==, or >= */
int *stat) /* success/failure */
{
xfs_agblock_t agbno; /* a.g. relative btree block number */
xfs_agnumber_t agno; /* allocation group number */
xfs_alloc_block_t *block=NULL; /* current btree block */
int diff; /* difference for the current key */
int error; /* error return value */
int keyno=0; /* current key number */
int level; /* level in the btree */
xfs_mount_t *mp; /* file system mount point */
XFS_STATS_INC(xs_abt_lookup);
/*
* Get the allocation group header, and the root block number.
*/
mp = cur->bc_mp;
{
xfs_agf_t *agf; /* a.g. freespace header */
agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
agno = be32_to_cpu(agf->agf_seqno);
agbno = be32_to_cpu(agf->agf_roots[cur->bc_btnum]);
}
/*
* 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--) {
xfs_buf_t *bp; /* buffer pointer for btree block */
xfs_daddr_t d; /* disk address of btree block */
/*
* Get the disk address we're looking for.
*/
d = XFS_AGB_TO_DADDR(mp, agno, agbno);
/*
* If the old buffer at this level is for a different block,
* throw it away, otherwise just use it.
*/
bp = cur->bc_bufs[level];
if (bp && XFS_BUF_ADDR(bp) != d)
bp = (xfs_buf_t *)0;
if (!bp) {
/*
* Need to get a new buffer. Read it, then
* set it in the cursor, releasing the old one.
*/
if ((error = xfs_btree_read_bufs(mp, cur->bc_tp, agno,
agbno, 0, &bp, XFS_ALLOC_BTREE_REF)))
return error;
xfs_btree_setbuf(cur, level, bp);
/*
* Point to the btree block, now that we have the buffer
*/
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
if ((error = xfs_btree_check_sblock(cur, block, level,
bp)))
return error;
} else
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
/*
* If we already had a key match at a higher level, we know
* we need to use the first entry in this block.
*/
if (diff == 0)
keyno = 1;
/*
* Otherwise we need to search this block. Do a binary search.
*/
else {
int high; /* high entry number */
xfs_alloc_key_t *kkbase=NULL;/* base of keys in block */
xfs_alloc_rec_t *krbase=NULL;/* base of records in block */
int low; /* low entry number */
/*
* Get a pointer to keys or records.
*/
if (level > 0)
kkbase = XFS_ALLOC_KEY_ADDR(block, 1, cur);
else
krbase = XFS_ALLOC_REC_ADDR(block, 1, cur);
/*
* Set low and high entry numbers, 1-based.
*/
low = 1;
if (!(high = be16_to_cpu(block->bb_numrecs))) {
/*
* If the block is empty, the tree must
* be an empty leaf.
*/
ASSERT(level == 0 && cur->bc_nlevels == 1);
cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
*stat = 0;
return 0;
}
/*
* Binary search the block.
*/
while (low <= high) {
xfs_extlen_t blockcount; /* key value */
xfs_agblock_t startblock; /* key value */
XFS_STATS_INC(xs_abt_compare);
/*
* keyno is average of low and high.
*/
keyno = (low + high) >> 1;
/*
* Get startblock & blockcount.
*/
if (level > 0) {
xfs_alloc_key_t *kkp;
kkp = kkbase + keyno - 1;
startblock = be32_to_cpu(kkp->ar_startblock);
blockcount = be32_to_cpu(kkp->ar_blockcount);
} else {
xfs_alloc_rec_t *krp;
krp = krbase + keyno - 1;
startblock = be32_to_cpu(krp->ar_startblock);
blockcount = be32_to_cpu(krp->ar_blockcount);
}
/*
* Compute difference to get next direction.
*/
if (cur->bc_btnum == XFS_BTNUM_BNO)
diff = (int)startblock -
(int)cur->bc_rec.a.ar_startblock;
else if (!(diff = (int)blockcount -
(int)cur->bc_rec.a.ar_blockcount))
diff = (int)startblock -
(int)cur->bc_rec.a.ar_startblock;
/*
* Less than, move right.
*/
if (diff < 0)
low = keyno + 1;
/*
* Greater than, move left.
*/
else if (diff > 0)
high = keyno - 1;
/*
* Equal, we're done.
*/
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;
agbno = be32_to_cpu(*XFS_ALLOC_PTR_ADDR(block, keyno, cur));
#ifdef DEBUG
if ((error = xfs_btree_check_sptr(cur, agbno, level)))
return error;
#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.
*/
if (dir == XFS_LOOKUP_GE &&
keyno > be16_to_cpu(block->bb_numrecs) &&
be32_to_cpu(block->bb_rightsib) != NULLAGBLOCK) {
int i;
cur->bc_ptrs[0] = keyno;
if ((error = xfs_alloc_increment(cur, 0, &i)))
return error;
XFS_WANT_CORRUPTED_RETURN(i == 1);
*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 > be16_to_cpu(block->bb_numrecs))
*stat = 0;
else
*stat = ((dir != XFS_LOOKUP_EQ) || (diff == 0));
return 0;
}
/*
* Move 1 record left from cur/level if possible.
* Update cur to reflect the new path.
*/
STATIC int /* error */
xfs_alloc_lshift(
xfs_btree_cur_t *cur, /* btree cursor */
int level, /* level to shift record on */
int *stat) /* success/failure */
{
int error; /* error return value */
#ifdef DEBUG
int i; /* loop index */
#endif
xfs_alloc_key_t key; /* key value for leaf level upward */
xfs_buf_t *lbp; /* buffer for left neighbor block */
xfs_alloc_block_t *left; /* left neighbor btree block */
int nrec; /* new number of left block entries */
xfs_buf_t *rbp; /* buffer for right (current) block */
xfs_alloc_block_t *right; /* right (current) btree block */
xfs_alloc_key_t *rkp=NULL; /* key pointer for right block */
xfs_alloc_ptr_t *rpp=NULL; /* address pointer for right block */
xfs_alloc_rec_t *rrp=NULL; /* record pointer for right block */
/*
* Set up variables for this block as "right".
*/
rbp = cur->bc_bufs[level];
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, right, level, rbp)))
return error;
#endif
/*
* If we've got no left sibling then we can't shift an entry left.
*/
if (be32_to_cpu(right->bb_leftsib) == NULLAGBLOCK) {
*stat = 0;
return 0;
}
/*
* 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) {
*stat = 0;
return 0;
}
/*
* Set up the left neighbor as "left".
*/
if ((error = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, be32_to_cpu(right->bb_leftsib),
0, &lbp, XFS_ALLOC_BTREE_REF)))
return error;
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
return error;
/*
* If it's full, it can't take another entry.
*/
if (be16_to_cpu(left->bb_numrecs) == XFS_ALLOC_BLOCK_MAXRECS(level, cur)) {
*stat = 0;
return 0;
}
nrec = be16_to_cpu(left->bb_numrecs) + 1;
/*
* If non-leaf, copy a key and a ptr to the left block.
*/
if (level > 0) {
xfs_alloc_key_t *lkp; /* key pointer for left block */
xfs_alloc_ptr_t *lpp; /* address pointer for left block */
lkp = XFS_ALLOC_KEY_ADDR(left, nrec, cur);
rkp = XFS_ALLOC_KEY_ADDR(right, 1, cur);
*lkp = *rkp;
xfs_alloc_log_keys(cur, lbp, nrec, nrec);
lpp = XFS_ALLOC_PTR_ADDR(left, nrec, cur);
rpp = XFS_ALLOC_PTR_ADDR(right, 1, cur);
#ifdef DEBUG
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(*rpp), level)))
return error;
#endif
*lpp = *rpp; /* INT_: copy */
xfs_alloc_log_ptrs(cur, lbp, nrec, nrec);
xfs_btree_check_key(cur->bc_btnum, lkp - 1, lkp);
}
/*
* If leaf, copy a record to the left block.
*/
else {
xfs_alloc_rec_t *lrp; /* record pointer for left block */
lrp = XFS_ALLOC_REC_ADDR(left, nrec, cur);
rrp = XFS_ALLOC_REC_ADDR(right, 1, cur);
*lrp = *rrp;
xfs_alloc_log_recs(cur, lbp, nrec, nrec);
xfs_btree_check_rec(cur->bc_btnum, lrp - 1, lrp);
}
/*
* Bump and log left's numrecs, decrement and log right's numrecs.
*/
be16_add(&left->bb_numrecs, 1);
xfs_alloc_log_block(cur->bc_tp, lbp, XFS_BB_NUMRECS);
be16_add(&right->bb_numrecs, -1);
xfs_alloc_log_block(cur->bc_tp, rbp, XFS_BB_NUMRECS);
/*
* Slide the contents of right down one entry.
*/
if (level > 0) {
#ifdef DEBUG
for (i = 0; i < be16_to_cpu(right->bb_numrecs); i++) {
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(rpp[i + 1]),
level)))
return error;
}
#endif
memmove(rkp, rkp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rkp));
memmove(rpp, rpp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rpp));
xfs_alloc_log_keys(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
xfs_alloc_log_ptrs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
} else {
memmove(rrp, rrp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rrp));
xfs_alloc_log_recs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
key.ar_startblock = rrp->ar_startblock;
key.ar_blockcount = rrp->ar_blockcount;
rkp = &key;
}
/*
* Update the parent key values of right.
*/
if ((error = xfs_alloc_updkey(cur, rkp, level + 1)))
return error;
/*
* Slide the cursor value left one.
*/
cur->bc_ptrs[level]--;
*stat = 1;
return 0;
}
/*
* Allocate a new root block, fill it in.
*/
STATIC int /* error */
xfs_alloc_newroot(
xfs_btree_cur_t *cur, /* btree cursor */
int *stat) /* success/failure */
{
int error; /* error return value */
xfs_agblock_t lbno; /* left block number */
xfs_buf_t *lbp; /* left btree buffer */
xfs_alloc_block_t *left; /* left btree block */
xfs_mount_t *mp; /* mount structure */
xfs_agblock_t nbno; /* new block number */
xfs_buf_t *nbp; /* new (root) buffer */
xfs_alloc_block_t *new; /* new (root) btree block */
int nptr; /* new value for key index, 1 or 2 */
xfs_agblock_t rbno; /* right block number */
xfs_buf_t *rbp; /* right btree buffer */
xfs_alloc_block_t *right; /* right btree block */
mp = cur->bc_mp;
ASSERT(cur->bc_nlevels < XFS_AG_MAXLEVELS(mp));
/*
* Get a buffer from the freelist blocks, for the new root.
*/
if ((error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
&nbno)))
return error;
/*
* None available, we fail.
*/
if (nbno == NULLAGBLOCK) {
*stat = 0;
return 0;
}
xfs_trans_agbtree_delta(cur->bc_tp, 1);
nbp = xfs_btree_get_bufs(mp, cur->bc_tp, cur->bc_private.a.agno, nbno,
0);
new = XFS_BUF_TO_ALLOC_BLOCK(nbp);
/*
* Set the root data in the a.g. freespace structure.
*/
{
xfs_agf_t *agf; /* a.g. freespace header */
xfs_agnumber_t seqno;
agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
agf->agf_roots[cur->bc_btnum] = cpu_to_be32(nbno);
be32_add(&agf->agf_levels[cur->bc_btnum], 1);
seqno = be32_to_cpu(agf->agf_seqno);
mp->m_perag[seqno].pagf_levels[cur->bc_btnum]++;
xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp,
XFS_AGF_ROOTS | XFS_AGF_LEVELS);
}
/*
* At the previous root level there are now two blocks: the old
* root, and the new block generated when it was split.
* We don't know which one the cursor is pointing at, so we
* set up variables "left" and "right" for each case.
*/
lbp = cur->bc_bufs[cur->bc_nlevels - 1];
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, left, cur->bc_nlevels - 1, lbp)))
return error;
#endif
if (be32_to_cpu(left->bb_rightsib) != NULLAGBLOCK) {
/*
* Our block is left, pick up the right block.
*/
lbno = XFS_DADDR_TO_AGBNO(mp, XFS_BUF_ADDR(lbp));
rbno = be32_to_cpu(left->bb_rightsib);
if ((error = xfs_btree_read_bufs(mp, cur->bc_tp,
cur->bc_private.a.agno, rbno, 0, &rbp,
XFS_ALLOC_BTREE_REF)))
return error;
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
if ((error = xfs_btree_check_sblock(cur, right,
cur->bc_nlevels - 1, rbp)))
return error;
nptr = 1;
} else {
/*
* Our block is right, pick up the left block.
*/
rbp = lbp;
right = left;
rbno = XFS_DADDR_TO_AGBNO(mp, XFS_BUF_ADDR(rbp));
lbno = be32_to_cpu(right->bb_leftsib);
if ((error = xfs_btree_read_bufs(mp, cur->bc_tp,
cur->bc_private.a.agno, lbno, 0, &lbp,
XFS_ALLOC_BTREE_REF)))
return error;
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
if ((error = xfs_btree_check_sblock(cur, left,
cur->bc_nlevels - 1, lbp)))
return error;
nptr = 2;
}
/*
* Fill in the new block's btree header and log it.
*/
new->bb_magic = cpu_to_be32(xfs_magics[cur->bc_btnum]);
new->bb_level = cpu_to_be16(cur->bc_nlevels);
new->bb_numrecs = cpu_to_be16(2);
new->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
new->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
xfs_alloc_log_block(cur->bc_tp, nbp, XFS_BB_ALL_BITS);
ASSERT(lbno != NULLAGBLOCK && rbno != NULLAGBLOCK);
/*
* Fill in the key data in the new root.
*/
{
xfs_alloc_key_t *kp; /* btree key pointer */
kp = XFS_ALLOC_KEY_ADDR(new, 1, cur);
if (be16_to_cpu(left->bb_level) > 0) {
kp[0] = *XFS_ALLOC_KEY_ADDR(left, 1, cur); /* INT_: structure copy */
kp[1] = *XFS_ALLOC_KEY_ADDR(right, 1, cur);/* INT_: structure copy */
} else {
xfs_alloc_rec_t *rp; /* btree record pointer */
rp = XFS_ALLOC_REC_ADDR(left, 1, cur);
kp[0].ar_startblock = rp->ar_startblock;
kp[0].ar_blockcount = rp->ar_blockcount;
rp = XFS_ALLOC_REC_ADDR(right, 1, cur);
kp[1].ar_startblock = rp->ar_startblock;
kp[1].ar_blockcount = rp->ar_blockcount;
}
}
xfs_alloc_log_keys(cur, nbp, 1, 2);
/*
* Fill in the pointer data in the new root.
*/
{
xfs_alloc_ptr_t *pp; /* btree address pointer */
pp = XFS_ALLOC_PTR_ADDR(new, 1, cur);
pp[0] = cpu_to_be32(lbno);
pp[1] = cpu_to_be32(rbno);
}
xfs_alloc_log_ptrs(cur, nbp, 1, 2);
/*
* Fix up the cursor.
*/
xfs_btree_setbuf(cur, cur->bc_nlevels, nbp);
cur->bc_ptrs[cur->bc_nlevels] = nptr;
cur->bc_nlevels++;
*stat = 1;
return 0;
}
/*
* Move 1 record right from cur/level if possible.
* Update cur to reflect the new path.
*/
STATIC int /* error */
xfs_alloc_rshift(
xfs_btree_cur_t *cur, /* btree cursor */
int level, /* level to shift record on */
int *stat) /* success/failure */
{
int error; /* error return value */
int i; /* loop index */
xfs_alloc_key_t key; /* key value for leaf level upward */
xfs_buf_t *lbp; /* buffer for left (current) block */
xfs_alloc_block_t *left; /* left (current) btree block */
xfs_buf_t *rbp; /* buffer for right neighbor block */
xfs_alloc_block_t *right; /* right neighbor btree block */
xfs_alloc_key_t *rkp; /* key pointer for right block */
xfs_btree_cur_t *tcur; /* temporary cursor */
/*
* Set up variables for this block as "left".
*/
lbp = cur->bc_bufs[level];
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
return error;
#endif
/*
* If we've got no right sibling then we can't shift an entry right.
*/
if (be32_to_cpu(left->bb_rightsib) == NULLAGBLOCK) {
*stat = 0;
return 0;
}
/*
* If the cursor entry is the one that would be moved, don't
* do it... it's too complicated.
*/
if (cur->bc_ptrs[level] >= be16_to_cpu(left->bb_numrecs)) {
*stat = 0;
return 0;
}
/*
* Set up the right neighbor as "right".
*/
if ((error = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, be32_to_cpu(left->bb_rightsib),
0, &rbp, XFS_ALLOC_BTREE_REF)))
return error;
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
if ((error = xfs_btree_check_sblock(cur, right, level, rbp)))
return error;
/*
* If it's full, it can't take another entry.
*/
if (be16_to_cpu(right->bb_numrecs) == XFS_ALLOC_BLOCK_MAXRECS(level, cur)) {
*stat = 0;
return 0;
}
/*
* Make a hole at the start of the right neighbor block, then
* copy the last left block entry to the hole.
*/
if (level > 0) {
xfs_alloc_key_t *lkp; /* key pointer for left block */
xfs_alloc_ptr_t *lpp; /* address pointer for left block */
xfs_alloc_ptr_t *rpp; /* address pointer for right block */
lkp = XFS_ALLOC_KEY_ADDR(left, be16_to_cpu(left->bb_numrecs), cur);
lpp = XFS_ALLOC_PTR_ADDR(left, be16_to_cpu(left->bb_numrecs), cur);
rkp = XFS_ALLOC_KEY_ADDR(right, 1, cur);
rpp = XFS_ALLOC_PTR_ADDR(right, 1, cur);
#ifdef DEBUG
for (i = be16_to_cpu(right->bb_numrecs) - 1; i >= 0; i--) {
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(rpp[i]), level)))
return error;
}
#endif
memmove(rkp + 1, rkp, be16_to_cpu(right->bb_numrecs) * sizeof(*rkp));
memmove(rpp + 1, rpp, be16_to_cpu(right->bb_numrecs) * sizeof(*rpp));
#ifdef DEBUG
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(*lpp), level)))
return error;
#endif
*rkp = *lkp; /* INT_: copy */
*rpp = *lpp; /* INT_: copy */
xfs_alloc_log_keys(cur, rbp, 1, be16_to_cpu(right->bb_numrecs) + 1);
xfs_alloc_log_ptrs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs) + 1);
xfs_btree_check_key(cur->bc_btnum, rkp, rkp + 1);
} else {
xfs_alloc_rec_t *lrp; /* record pointer for left block */
xfs_alloc_rec_t *rrp; /* record pointer for right block */
lrp = XFS_ALLOC_REC_ADDR(left, be16_to_cpu(left->bb_numrecs), cur);
rrp = XFS_ALLOC_REC_ADDR(right, 1, cur);
memmove(rrp + 1, rrp, be16_to_cpu(right->bb_numrecs) * sizeof(*rrp));
*rrp = *lrp;
xfs_alloc_log_recs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs) + 1);
key.ar_startblock = rrp->ar_startblock;
key.ar_blockcount = rrp->ar_blockcount;
rkp = &key;
xfs_btree_check_rec(cur->bc_btnum, rrp, rrp + 1);
}
/*
* Decrement and log left's numrecs, bump and log right's numrecs.
*/
be16_add(&left->bb_numrecs, -1);
xfs_alloc_log_block(cur->bc_tp, lbp, XFS_BB_NUMRECS);
be16_add(&right->bb_numrecs, 1);
xfs_alloc_log_block(cur->bc_tp, rbp, XFS_BB_NUMRECS);
/*
* Using a temporary cursor, update the parent key values of the
* block on the right.
*/
if ((error = xfs_btree_dup_cursor(cur, &tcur)))
return error;
i = xfs_btree_lastrec(tcur, level);
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
if ((error = xfs_alloc_increment(tcur, level, &i)) ||
(error = xfs_alloc_updkey(tcur, rkp, level + 1)))
goto error0;
xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
*stat = 1;
return 0;
error0:
xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
return error;
}
/*
* Split cur/level block in half.
* Return new block number and its first record (to be inserted into parent).
*/
STATIC int /* error */
xfs_alloc_split(
xfs_btree_cur_t *cur, /* btree cursor */
int level, /* level to split */
xfs_agblock_t *bnop, /* output: block number allocated */
xfs_alloc_key_t *keyp, /* output: first key of new block */
xfs_btree_cur_t **curp, /* output: new cursor */
int *stat) /* success/failure */
{
int error; /* error return value */
int i; /* loop index/record number */
xfs_agblock_t lbno; /* left (current) block number */
xfs_buf_t *lbp; /* buffer for left block */
xfs_alloc_block_t *left; /* left (current) btree block */
xfs_agblock_t rbno; /* right (new) block number */
xfs_buf_t *rbp; /* buffer for right block */
xfs_alloc_block_t *right; /* right (new) btree block */
/*
* Allocate the new block from the freelist.
* If we can't do it, we're toast. Give up.
*/
if ((error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
&rbno)))
return error;
if (rbno == NULLAGBLOCK) {
*stat = 0;
return 0;
}
xfs_trans_agbtree_delta(cur->bc_tp, 1);
rbp = xfs_btree_get_bufs(cur->bc_mp, cur->bc_tp, cur->bc_private.a.agno,
rbno, 0);
/*
* Set up the new block as "right".
*/
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
/*
* "Left" is the current (according to the cursor) block.
*/
lbp = cur->bc_bufs[level];
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
return error;
#endif
/*
* Fill in the btree header for the new block.
*/
right->bb_magic = cpu_to_be32(xfs_magics[cur->bc_btnum]);
right->bb_level = left->bb_level;
right->bb_numrecs = cpu_to_be16(be16_to_cpu(left->bb_numrecs) / 2);
/*
* Make sure that if there's an odd number of entries now, that
* each new block will have the same number of entries.
*/
if ((be16_to_cpu(left->bb_numrecs) & 1) &&
cur->bc_ptrs[level] <= be16_to_cpu(right->bb_numrecs) + 1)
be16_add(&right->bb_numrecs, 1);
i = be16_to_cpu(left->bb_numrecs) - be16_to_cpu(right->bb_numrecs) + 1;
/*
* For non-leaf blocks, copy keys and addresses over to the new block.
*/
if (level > 0) {
xfs_alloc_key_t *lkp; /* left btree key pointer */
xfs_alloc_ptr_t *lpp; /* left btree address pointer */
xfs_alloc_key_t *rkp; /* right btree key pointer */
xfs_alloc_ptr_t *rpp; /* right btree address pointer */
lkp = XFS_ALLOC_KEY_ADDR(left, i, cur);
lpp = XFS_ALLOC_PTR_ADDR(left, i, cur);
rkp = XFS_ALLOC_KEY_ADDR(right, 1, cur);
rpp = XFS_ALLOC_PTR_ADDR(right, 1, cur);
#ifdef DEBUG
for (i = 0; i < be16_to_cpu(right->bb_numrecs); i++) {
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(lpp[i]), level)))
return error;
}
#endif
memcpy(rkp, lkp, be16_to_cpu(right->bb_numrecs) * sizeof(*rkp));
memcpy(rpp, lpp, be16_to_cpu(right->bb_numrecs) * sizeof(*rpp));
xfs_alloc_log_keys(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
xfs_alloc_log_ptrs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
*keyp = *rkp;
}
/*
* For leaf blocks, copy records over to the new block.
*/
else {
xfs_alloc_rec_t *lrp; /* left btree record pointer */
xfs_alloc_rec_t *rrp; /* right btree record pointer */
lrp = XFS_ALLOC_REC_ADDR(left, i, cur);
rrp = XFS_ALLOC_REC_ADDR(right, 1, cur);
memcpy(rrp, lrp, be16_to_cpu(right->bb_numrecs) * sizeof(*rrp));
xfs_alloc_log_recs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
keyp->ar_startblock = rrp->ar_startblock;
keyp->ar_blockcount = rrp->ar_blockcount;
}
/*
* Find the left block number by looking in the buffer.
* Adjust numrecs, sibling pointers.
*/
lbno = XFS_DADDR_TO_AGBNO(cur->bc_mp, XFS_BUF_ADDR(lbp));
be16_add(&left->bb_numrecs, -(be16_to_cpu(right->bb_numrecs)));
right->bb_rightsib = left->bb_rightsib;
left->bb_rightsib = cpu_to_be32(rbno);
right->bb_leftsib = cpu_to_be32(lbno);
xfs_alloc_log_block(cur->bc_tp, rbp, XFS_BB_ALL_BITS);
xfs_alloc_log_block(cur->bc_tp, 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 (be32_to_cpu(right->bb_rightsib) != NULLAGBLOCK) {
xfs_alloc_block_t *rrblock; /* rr btree block */
xfs_buf_t *rrbp; /* buffer for rrblock */
if ((error = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, be32_to_cpu(right->bb_rightsib), 0,
&rrbp, XFS_ALLOC_BTREE_REF)))
return error;
rrblock = XFS_BUF_TO_ALLOC_BLOCK(rrbp);
if ((error = xfs_btree_check_sblock(cur, rrblock, level, rrbp)))
return error;
rrblock->bb_leftsib = cpu_to_be32(rbno);
xfs_alloc_log_block(cur->bc_tp, 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] > be16_to_cpu(left->bb_numrecs) + 1) {
xfs_btree_setbuf(cur, level, rbp);
cur->bc_ptrs[level] -= be16_to_cpu(left->bb_numrecs);
}
/*
* If there are more levels, we'll need another cursor which refers to
* the right block, no matter where this cursor was.
*/
if (level + 1 < cur->bc_nlevels) {
if ((error = xfs_btree_dup_cursor(cur, curp)))
return error;
(*curp)->bc_ptrs[level + 1]++;
}
*bnop = rbno;
*stat = 1;
return 0;
}
/*
* Update keys at all levels from here to the root along the cursor's path.
*/
STATIC int /* error */
xfs_alloc_updkey(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_alloc_key_t *keyp, /* new key value to update to */
int level) /* starting level for update */
{
int ptr; /* index of key in block */
/*
* 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++) {
xfs_alloc_block_t *block; /* btree block */
xfs_buf_t *bp; /* buffer for block */
#ifdef DEBUG
int error; /* error return value */
#endif
xfs_alloc_key_t *kp; /* ptr to btree block keys */
bp = cur->bc_bufs[level];
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, block, level, bp)))
return error;
#endif
ptr = cur->bc_ptrs[level];
kp = XFS_ALLOC_KEY_ADDR(block, ptr, cur);
*kp = *keyp;
xfs_alloc_log_keys(cur, bp, ptr, ptr);
}
return 0;
}
/*
* Externally visible routines.
*/
/*
* Decrement cursor by one record at the level.
* For nonzero levels the leaf-ward information is untouched.
*/
int /* error */
xfs_alloc_decrement(
xfs_btree_cur_t *cur, /* btree cursor */
int level, /* level in btree, 0 is leaf */
int *stat) /* success/failure */
{
xfs_alloc_block_t *block; /* btree block */
int error; /* error return value */
int lev; /* btree level */
ASSERT(level < cur->bc_nlevels);
/*
* Read-ahead to the left at this level.
*/
xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA);
/*
* Decrement the ptr at this level. If we're still in the block
* then we're done.
*/
if (--cur->bc_ptrs[level] > 0) {
*stat = 1;
return 0;
}
/*
* Get a pointer to the btree block.
*/
block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[level]);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, block, level,
cur->bc_bufs[level])))
return error;
#endif
/*
* If we just went off the left edge of the tree, return failure.
*/
if (be32_to_cpu(block->bb_leftsib) == NULLAGBLOCK) {
*stat = 0;
return 0;
}
/*
* 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, we're going to read it
* in the next loop.
*/
xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA);
}
/*
* If we went off the root then we are seriously confused.
*/
ASSERT(lev < cur->bc_nlevels);
/*
* Now walk back down the tree, fixing up the cursor's buffer
* pointers and key numbers.
*/
for (block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[lev]); lev > level; ) {
xfs_agblock_t agbno; /* block number of btree block */
xfs_buf_t *bp; /* buffer pointer for block */
agbno = be32_to_cpu(*XFS_ALLOC_PTR_ADDR(block, cur->bc_ptrs[lev], cur));
if ((error = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, agbno, 0, &bp,
XFS_ALLOC_BTREE_REF)))
return error;
lev--;
xfs_btree_setbuf(cur, lev, bp);
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
if ((error = xfs_btree_check_sblock(cur, block, lev, bp)))
return error;
cur->bc_ptrs[lev] = be16_to_cpu(block->bb_numrecs);
}
*stat = 1;
return 0;
}
/*
* Delete the record pointed to by cur.
* The cursor refers to the place where the record was (could be inserted)
* when the operation returns.
*/
int /* error */
xfs_alloc_delete(
xfs_btree_cur_t *cur, /* btree cursor */
int *stat) /* success/failure */
{
int error; /* error return value */
int i; /* result code */
int level; /* btree level */
/*
* Go up the tree, starting at leaf level.
* If 2 is returned then a join was done; go to the next level.
* Otherwise we are done.
*/
for (level = 0, i = 2; i == 2; level++) {
if ((error = xfs_alloc_delrec(cur, level, &i)))
return error;
}
if (i == 0) {
for (level = 1; level < cur->bc_nlevels; level++) {
if (cur->bc_ptrs[level] == 0) {
if ((error = xfs_alloc_decrement(cur, level, &i)))
return error;
break;
}
}
}
*stat = i;
return 0;
}
/*
* Get the data from the pointed-to record.
*/
int /* error */
xfs_alloc_get_rec(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agblock_t *bno, /* output: starting block of extent */
xfs_extlen_t *len, /* output: length of extent */
int *stat) /* output: success/failure */
{
xfs_alloc_block_t *block; /* btree block */
#ifdef DEBUG
int error; /* error return value */
#endif
int ptr; /* record number */
ptr = cur->bc_ptrs[0];
block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[0]);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, block, 0, cur->bc_bufs[0])))
return error;
#endif
/*
* Off the right end or left end, return failure.
*/
if (ptr > be16_to_cpu(block->bb_numrecs) || ptr <= 0) {
*stat = 0;
return 0;
}
/*
* Point to the record and extract its data.
*/
{
xfs_alloc_rec_t *rec; /* record data */
rec = XFS_ALLOC_REC_ADDR(block, ptr, cur);
*bno = be32_to_cpu(rec->ar_startblock);
*len = be32_to_cpu(rec->ar_blockcount);
}
*stat = 1;
return 0;
}
/*
* Increment cursor by one record at the level.
* For nonzero levels the leaf-ward information is untouched.
*/
int /* error */
xfs_alloc_increment(
xfs_btree_cur_t *cur, /* btree cursor */
int level, /* level in btree, 0 is leaf */
int *stat) /* success/failure */
{
xfs_alloc_block_t *block; /* btree block */
xfs_buf_t *bp; /* tree block buffer */
int error; /* error return value */
int lev; /* btree 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.
*/
bp = cur->bc_bufs[level];
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, block, level, bp)))
return error;
#endif
/*
* Increment the ptr at this level. If we're still in the block
* then we're done.
*/
if (++cur->bc_ptrs[level] <= be16_to_cpu(block->bb_numrecs)) {
*stat = 1;
return 0;
}
/*
* If we just went off the right edge of the tree, return failure.
*/
if (be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK) {
*stat = 0;
return 0;
}
/*
* 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++) {
bp = cur->bc_bufs[lev];
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, block, lev, bp)))
return error;
#endif
if (++cur->bc_ptrs[lev] <= be16_to_cpu(block->bb_numrecs))
break;
/*
* Read-ahead the right block, we're going to read it
* in the next loop.
*/
xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
}
/*
* If we went off the root then we are seriously confused.
*/
ASSERT(lev < cur->bc_nlevels);
/*
* Now walk back down the tree, fixing up the cursor's buffer
* pointers and key numbers.
*/
for (bp = cur->bc_bufs[lev], block = XFS_BUF_TO_ALLOC_BLOCK(bp);
lev > level; ) {
xfs_agblock_t agbno; /* block number of btree block */
agbno = be32_to_cpu(*XFS_ALLOC_PTR_ADDR(block, cur->bc_ptrs[lev], cur));
if ((error = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, agbno, 0, &bp,
XFS_ALLOC_BTREE_REF)))
return error;
lev--;
xfs_btree_setbuf(cur, lev, bp);
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
if ((error = xfs_btree_check_sblock(cur, block, lev, bp)))
return error;
cur->bc_ptrs[lev] = 1;
}
*stat = 1;
return 0;
}
/*
* Insert the current record at the point referenced by cur.
* The cursor may be inconsistent on return if splits have been done.
*/
int /* error */
xfs_alloc_insert(
xfs_btree_cur_t *cur, /* btree cursor */
int *stat) /* success/failure */
{
int error; /* error return value */
int i; /* result value, 0 for failure */
int level; /* current level number in btree */
xfs_agblock_t nbno; /* new block number (split result) */
xfs_btree_cur_t *ncur; /* new cursor (split result) */
xfs_alloc_rec_t nrec; /* record being inserted this level */
xfs_btree_cur_t *pcur; /* previous level's cursor */
level = 0;
nbno = NULLAGBLOCK;
nrec.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
nrec.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
ncur = (xfs_btree_cur_t *)0;
pcur = cur;
/*
* Loop going up the tree, starting at the leaf level.
* Stop when we don't get a split block, that must mean that
* the insert is finished with this level.
*/
do {
/*
* Insert nrec/nbno into this level of the tree.
* Note if we fail, nbno will be null.
*/
if ((error = xfs_alloc_insrec(pcur, level++, &nbno, &nrec, &ncur,
&i))) {
if (pcur != cur)
xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
return error;
}
/*
* See if the cursor we just used is trash.
* Can't trash the caller's cursor, but otherwise we should
* if ncur is a new cursor or we're about to be done.
*/
if (pcur != cur && (ncur || nbno == NULLAGBLOCK)) {
cur->bc_nlevels = pcur->bc_nlevels;
xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR);
}
/*
* If we got a new cursor, switch to it.
*/
if (ncur) {
pcur = ncur;
ncur = (xfs_btree_cur_t *)0;
}
} while (nbno != NULLAGBLOCK);
*stat = i;
return 0;
}
/*
* Lookup the record equal to [bno, len] in the btree given by cur.
*/
int /* error */
xfs_alloc_lookup_eq(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agblock_t bno, /* starting block of extent */
xfs_extlen_t len, /* length of extent */
int *stat) /* success/failure */
{
cur->bc_rec.a.ar_startblock = bno;
cur->bc_rec.a.ar_blockcount = len;
return xfs_alloc_lookup(cur, XFS_LOOKUP_EQ, stat);
}
/*
* Lookup the first record greater than or equal to [bno, len]
* in the btree given by cur.
*/
int /* error */
xfs_alloc_lookup_ge(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agblock_t bno, /* starting block of extent */
xfs_extlen_t len, /* length of extent */
int *stat) /* success/failure */
{
cur->bc_rec.a.ar_startblock = bno;
cur->bc_rec.a.ar_blockcount = len;
return xfs_alloc_lookup(cur, XFS_LOOKUP_GE, stat);
}
/*
* Lookup the first record less than or equal to [bno, len]
* in the btree given by cur.
*/
int /* error */
xfs_alloc_lookup_le(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agblock_t bno, /* starting block of extent */
xfs_extlen_t len, /* length of extent */
int *stat) /* success/failure */
{
cur->bc_rec.a.ar_startblock = bno;
cur->bc_rec.a.ar_blockcount = len;
return xfs_alloc_lookup(cur, XFS_LOOKUP_LE, stat);
}
/*
* Update the record referred to by cur, to the value given by [bno, len].
* This either works (return 0) or gets an EFSCORRUPTED error.
*/
int /* error */
xfs_alloc_update(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agblock_t bno, /* starting block of extent */
xfs_extlen_t len) /* length of extent */
{
xfs_alloc_block_t *block; /* btree block to update */
int error; /* error return value */
int ptr; /* current record number (updating) */
ASSERT(len > 0);
/*
* Pick up the a.g. freelist struct and the current block.
*/
block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[0]);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, block, 0, cur->bc_bufs[0])))
return error;
#endif
/*
* Get the address of the rec to be updated.
*/
ptr = cur->bc_ptrs[0];
{
xfs_alloc_rec_t *rp; /* pointer to updated record */
rp = XFS_ALLOC_REC_ADDR(block, ptr, cur);
/*
* Fill in the new contents and log them.
*/
rp->ar_startblock = cpu_to_be32(bno);
rp->ar_blockcount = cpu_to_be32(len);
xfs_alloc_log_recs(cur, cur->bc_bufs[0], ptr, ptr);
}
/*
* If it's the by-size btree and it's the last leaf block and
* it's the last record... then update the size of the longest
* extent in the a.g., which we cache in the a.g. freelist header.
*/
if (cur->bc_btnum == XFS_BTNUM_CNT &&
be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK &&
ptr == be16_to_cpu(block->bb_numrecs)) {
xfs_agf_t *agf; /* a.g. freespace header */
xfs_agnumber_t seqno;
agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
seqno = be32_to_cpu(agf->agf_seqno);
cur->bc_mp->m_perag[seqno].pagf_longest = len;
agf->agf_longest = cpu_to_be32(len);
xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp,
XFS_AGF_LONGEST);
}
/*
* Updating first record in leaf. Pass new key value up to our parent.
*/
if (ptr == 1) {
xfs_alloc_key_t key; /* key containing [bno, len] */
key.ar_startblock = cpu_to_be32(bno);
key.ar_blockcount = cpu_to_be32(len);
if ((error = xfs_alloc_updkey(cur, &key, 1)))
return error;
}
return 0;
}
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