File: [Development] / xfs-linux / xfs_alloc_btree.c (download)
Revision 1.15, Sat May 28 21:23:19 1994 UTC (23 years, 4 months ago) by doucette
Branch: MAIN
Changes since 1.14: +9 -4
lines
Replace a.g. freelist with an array of blocks stored in the 4th bb.
|
#ident "$Revision: 1.20 $"
/*
* Free space allocation for xFS.
*/
#include <sys/param.h>
#ifdef SIM
#define _KERNEL
#endif
#include <sys/buf.h>
#ifdef SIM
#undef _KERNEL
#endif
#include <sys/vnode.h>
#include <sys/uuid.h>
#include <sys/debug.h>
#include <stddef.h>
#ifdef SIM
#include <stdlib.h>
#include <bstring.h>
#else
#include <sys/systm.h>
#endif
#include "xfs_types.h"
#include "xfs_inum.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_alloc.h"
#ifdef SIM
#include "sim.h"
#endif
#if !defined(SIM) || !defined(XFSDEBUG)
#define kmem_check() /* dummy for memory-allocation checking */
#endif
/*
* Prototypes for 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 /* fail/done/go-on */
xfs_alloc_delrec(
xfs_btree_cur_t *cur, /* btree cursor */
int level); /* level removing record from */
/*
* Insert one record/level. Return information to the caller
* allowing the next level up to proceed if necessary.
*/
STATIC int /* success/failure */
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 */
#ifdef XFSDEBUG
/*
* Check key consistency in one btree level, then recurse down to the next.
*/
STATIC void
xfs_alloc_kcheck_btree(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agf_t *agf, /* a.g. freespace header */
xfs_agblock_t bno, /* block number to check */
int level, /* level of the block */
xfs_alloc_key_t *keyp); /* value of expected first key */
#endif /* XFSDEBUG */
/*
* Log header fields from a btree block.
*/
STATIC void
xfs_alloc_log_block(
xfs_trans_t *tp, /* transaction pointer */
buf_t *bp, /* buffer containing btree block */
int fields); /* mask of fields: XFS_BB_... */
/*
* Log keys from a btree block (nonleaf).
*/
STATIC void
xfs_alloc_log_keys(
xfs_btree_cur_t *cur, /* btree cursor */
buf_t *bp, /* buffer containing btree block */
int kfirst, /* index of first key to log */
int klast); /* index of last key to log */
/*
* Log block pointer fields from a btree block (nonleaf).
*/
STATIC void
xfs_alloc_log_ptrs(
xfs_btree_cur_t *cur, /* btree cursor */
buf_t *bp, /* buffer containing btree block */
int pfirst, /* index of first pointer to log */
int plast); /* index of last pointer to log */
/*
* Log records from a btree block (leaf).
*/
STATIC void
xfs_alloc_log_recs(
xfs_btree_cur_t *cur, /* btree cursor */
buf_t *bp, /* buffer containing btree block */
int rfirst, /* index of first record to log */
int rlast); /* index of last record to log */
/*
* 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 /* success/failure */
xfs_alloc_lookup(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_lookup_t dir); /* <=, ==, or >= */
/*
* Move 1 record left from cur/level if possible.
* Update cur to reflect the new path.
*/
STATIC int /* success/failure */
xfs_alloc_lshift(
xfs_btree_cur_t *cur, /* btree cursor */
int level); /* level to shift record on */
/*
* Allocate a new root block, fill it in.
*/
STATIC int /* success/failure */
xfs_alloc_newroot(
xfs_btree_cur_t *cur); /* btree cursor */
#ifdef XFSDEBUG
/*
* Guts of xfs_alloc_rcheck. For each level in the btree, check
* all its blocks for consistency.
*/
STATIC void
xfs_alloc_rcheck_btree(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agf_t *agf, /* a.g. freespace header */
xfs_agblock_t rbno, /* root block number */
int levels); /* number of levels in the btree */
#endif /* XFSDEBUG */
#ifdef XFSDEBUG
/*
* Check one btree block for record consistency.
*/
STATIC xfs_agblock_t /* next block to process */
xfs_alloc_rcheck_btree_block(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agnumber_t agno, /* allocation group number */
xfs_agblock_t bno, /* block number to check */
xfs_agblock_t *fbno, /* output: first block at next level */
void *rec, /* previous record/key value */
int level); /* level of this block */
#endif /* XFSDEBUG */
/*
* Move 1 record right from cur/level if possible.
* Update cur to reflect the new path.
*/
STATIC int /* success/failure */
xfs_alloc_rshift(
xfs_btree_cur_t *cur, /* btree cursor */
int level); /* level to shift record on */
/*
* Split cur/level block in half.
* Return new block number and its first record (to be inserted into parent).
* Also returns a new cursor in this case, for next level of insert to use.
*/
STATIC int /* success/failure */
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 */
/*
* Update keys at all levels from here to the root along the cursor's path.
*/
STATIC void
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 */
/*
* 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 /* fail/done/go-on */
xfs_alloc_delrec(
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level removing record from */
{
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 */
buf_t *bp; /* buffer for block */
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 */
buf_t *lbp; /* left block's buffer pointer */
xfs_alloc_block_t *left; /* left btree block */
xfs_alloc_key_t *lkp; /* left block key pointer */
xfs_alloc_ptr_t *lpp; /* left block address pointer */
int lrecs; /* number of records in left block */
xfs_alloc_rec_t *lrp; /* left block record pointer */
int ptr; /* index in btree block for this rec */
xfs_agblock_t rbno; /* right block's block number */
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; /* number of records in right block */
xfs_alloc_rec_t *rrp; /* right block record pointer */
xfs_btree_cur_t *tcur; /* temporary btree cursor */
xfs_alloc_rcheck(cur);
/*
* Get the index of the entry being deleted, check for nothing there.
*/
ptr = cur->bc_ptrs[level];
if (ptr == 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);
xfs_btree_check_sblock(cur, block, level);
/*
* Fail if we're off the end of the block.
*/
if (ptr > block->bb_numrecs)
return 0;
/*
* 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);
for (i = ptr; i < block->bb_numrecs; i++) {
lkp[i - 1] = lkp[i];
xfs_btree_check_sptr(cur, lpp[i], level);
lpp[i - 1] = lpp[i];
}
if (ptr < i) {
xfs_alloc_log_ptrs(cur, bp, ptr, i - 1);
xfs_alloc_log_keys(cur, bp, ptr, i - 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);
for (i = ptr; i < block->bb_numrecs; i++)
lrp[i - 1] = lrp[i];
if (ptr < i)
xfs_alloc_log_recs(cur, bp, ptr, i - 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.
*/
block->bb_numrecs--;
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);
if (level == 0 &&
cur->bc_btnum == XFS_BTNUM_CNT &&
block->bb_rightsib == NULLAGBLOCK &&
ptr > block->bb_numrecs) {
ASSERT(ptr == block->bb_numrecs + 1);
/*
* There are still records in the block. Grab the size
* from the last one.
*/
if (block->bb_numrecs) {
rrp = XFS_ALLOC_REC_ADDR(block, block->bb_numrecs, cur);
agf->agf_longest = rrp->ar_blockcount;
}
/*
* No free extents left.
*/
else
agf->agf_longest = 0;
xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp,
XFS_AGF_LONGEST);
}
/*
* If we get here for a non-leaf block,
* we just did a join at the previous level.
* Make the cursor point to the good (left) key.
*/
if (level > 0)
xfs_alloc_decrement(cur, level);
/*
* 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 (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 = agf->agf_roots[cur->bc_btnum];
agf->agf_roots[cur->bc_btnum] = *lpp;
agf->agf_levels[cur->bc_btnum]--;
/*
* Put this buffer/block on the ag's freelist.
*/
xfs_alloc_put_freelist(cur->bc_tp,
cur->bc_private.a.agbp, NULL, bno);
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, 0);
cur->bc_nlevels--;
}
xfs_alloc_rcheck(cur);
kmem_check();
return 1;
}
/*
* If we deleted the leftmost entry in the block, update the
* key values above us in the tree.
*/
if (ptr == 1)
xfs_alloc_updkey(cur, lkp, level + 1);
/*
* If the number of records remaining in the block is at least
* the minimum, we're done.
*/
if (block->bb_numrecs >= XFS_ALLOC_BLOCK_MINRECS(level, cur)) {
kmem_check();
xfs_alloc_rcheck(cur);
return 1;
}
/*
* 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 = block->bb_rightsib;
lbno = 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.
*/
tcur = xfs_btree_dup_cursor(cur);
/*
* 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.
*/
xfs_btree_lastrec(tcur, level);
xfs_alloc_increment(tcur, level);
xfs_btree_lastrec(tcur, level);
/*
* Grab a pointer to the block.
*/
rbp = tcur->bc_bufs[level];
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
xfs_btree_check_sblock(cur, right, level);
/*
* Grab the current block number, for future use.
*/
bno = 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 (right->bb_numrecs - 1 >=
XFS_ALLOC_BLOCK_MINRECS(level, cur) &&
xfs_alloc_lshift(tcur, level)) {
ASSERT(block->bb_numrecs >=
XFS_ALLOC_BLOCK_MINRECS(level, cur));
xfs_btree_del_cursor(tcur);
kmem_check();
return 1;
}
/*
* 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 = right->bb_numrecs;
if (lbno != NULLAGBLOCK) {
xfs_btree_firstrec(tcur, level);
xfs_alloc_decrement(tcur, level);
}
}
/*
* 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.
*/
xfs_btree_firstrec(tcur, level);
xfs_alloc_decrement(tcur, level);
xfs_btree_firstrec(tcur, level);
/*
* Grab a pointer to the block.
*/
lbp = tcur->bc_bufs[level];
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
xfs_btree_check_sblock(cur, left, level);
/*
* Grab the current block number, for future use.
*/
bno = 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 (left->bb_numrecs - 1 >=
XFS_ALLOC_BLOCK_MINRECS(level, cur) &&
xfs_alloc_rshift(tcur, level)) {
ASSERT(block->bb_numrecs >=
XFS_ALLOC_BLOCK_MINRECS(level, cur));
xfs_btree_del_cursor(tcur);
cur->bc_ptrs[level]++;
kmem_check();
return 1;
}
/*
* Otherwise, grab the number of records in right for
* future reference.
*/
lrecs = left->bb_numrecs;
}
/*
* Delete the temp cursor, we're done with it.
*/
xfs_btree_del_cursor(tcur);
/*
* 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 + 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;
lbp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, lbno, 0);
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
xfs_btree_check_sblock(cur, left, level);
}
/*
* If that won't work, see if we can join with the right neighbor block.
*/
else if (rbno != NULLAGBLOCK &&
rrecs + 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;
rbp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, rbno, 0);
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
xfs_btree_check_sblock(cur, right, level);
}
/*
* Otherwise, we can't fix the imbalance.
* Just return. This is probably a logic error, but it's not fatal.
*/
else {
xfs_alloc_rcheck(cur);
kmem_check();
return 1;
}
/*
* 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, left->bb_numrecs + 1, cur);
lpp = XFS_ALLOC_PTR_ADDR(left, left->bb_numrecs + 1, cur);
rkp = XFS_ALLOC_KEY_ADDR(right, 1, cur);
rpp = XFS_ALLOC_PTR_ADDR(right, 1, cur);
for (i = 0; i < right->bb_numrecs; i++) {
lkp[i] = rkp[i];
xfs_btree_check_sptr(cur, rpp[i], level);
lpp[i] = rpp[i];
}
xfs_alloc_log_keys(cur, lbp, left->bb_numrecs + 1,
left->bb_numrecs + right->bb_numrecs);
xfs_alloc_log_ptrs(cur, lbp, left->bb_numrecs + 1,
left->bb_numrecs + right->bb_numrecs);
} else {
/*
* It's a leaf. Move records.
*/
lrp = XFS_ALLOC_REC_ADDR(left, left->bb_numrecs + 1, cur);
rrp = XFS_ALLOC_REC_ADDR(right, 1, cur);
for (i = 0; i < right->bb_numrecs; i++)
lrp[i] = rrp[i];
xfs_alloc_log_recs(cur, lbp, left->bb_numrecs + 1,
left->bb_numrecs + 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] += 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)
xfs_alloc_increment(cur, level + 1);
/*
* Fix up the number of records in the surviving block.
*/
left->bb_numrecs += 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 (left->bb_rightsib != NULLAGBLOCK) {
xfs_alloc_block_t *rrblock;
buf_t *rrbp;
rrbp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, left->bb_rightsib, 0);
rrblock = XFS_BUF_TO_ALLOC_BLOCK(rrbp);
xfs_btree_check_sblock(cur, rrblock, level);
rrblock->bb_leftsib = lbno;
xfs_alloc_log_block(cur->bc_tp, rrbp, XFS_BB_LEFTSIB);
}
/*
* Free the deleting block by putting it on the freelist.
*/
xfs_alloc_put_freelist(cur->bc_tp, cur->bc_private.a.agbp, NULL, rbno);
xfs_alloc_rcheck(cur);
kmem_check();
/*
* Return value means the next level up has something to do.
*/
return 2;
}
/*
* Insert one record/level. Return information to the caller
* allowing the next level up to proceed if necessary.
*/
STATIC int /* success/failure */
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 */
{
xfs_agf_t *agf; /* allocation group freelist header */
xfs_alloc_block_t *block; /* btree block record/key lives in */
buf_t *bp; /* buffer for block */
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 */
/*
* If we made it to the root level, allocate a new root block
* and we're done.
*/
if (level >= cur->bc_nlevels) {
i = xfs_alloc_newroot(cur);
*bnop = NULLAGBLOCK;
kmem_check();
return i;
}
xfs_alloc_rcheck(cur);
/*
* 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) {
kmem_check();
return 0;
}
/*
* Get pointers to the btree buffer and block.
*/
bp = cur->bc_bufs[level];
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
xfs_btree_check_sblock(cur, block, level);
#ifdef DEBUG
/*
* Check that the new entry is being inserted in the right place.
*/
if (ptr <= 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 (block->bb_numrecs == XFS_ALLOC_BLOCK_MAXRECS(level, cur)) {
/*
* First, try shifting an entry to the right neighbor.
*/
if (xfs_alloc_rshift(cur, level)) {
/* nothing */
}
/*
* Next, try shifting an entry to the left neighbor.
*/
else if (xfs_alloc_lshift(cur, level)) {
optr = ptr = cur->bc_ptrs[level];
}
/*
* 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.
*/
else if (xfs_alloc_split(cur, level, &nbno, &nkey, &ncur)) {
bp = cur->bc_bufs[level];
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
xfs_btree_check_sblock(cur, block, level);
ptr = cur->bc_ptrs[level];
nrec.ar_startblock = nkey.ar_startblock;
nrec.ar_blockcount = nkey.ar_blockcount;
}
/*
* Otherwise the insert fails.
*/
else {
kmem_check();
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);
for (i = block->bb_numrecs; i >= ptr; i--) {
kp[i] = kp[i - 1];
xfs_btree_check_sptr(cur, pp[i - 1], level);
pp[i] = pp[i - 1];
}
xfs_btree_check_sptr(cur, *bnop, level);
/*
* Now stuff the new data in, bump numrecs and log the new data.
*/
kp[i] = key;
pp[i] = *bnop;
block->bb_numrecs++;
xfs_alloc_log_keys(cur, bp, ptr, block->bb_numrecs);
xfs_alloc_log_ptrs(cur, bp, ptr, block->bb_numrecs);
#ifdef DEBUG
if (ptr < block->bb_numrecs)
xfs_btree_check_key(cur->bc_btnum, kp + i, kp + i + 1);
#endif
} else {
/*
* It's a leaf entry. Make a hole for the new record.
*/
rp = XFS_ALLOC_REC_ADDR(block, 1, cur);
for (i = block->bb_numrecs; i >= ptr; i--)
rp[i] = rp[i - 1];
/*
* Now stuff the new record in, bump numrecs
* and log the new data.
*/
rp[i] = *recp;
block->bb_numrecs++;
xfs_alloc_log_recs(cur, bp, ptr, block->bb_numrecs);
#ifdef DEBUG
if (ptr < block->bb_numrecs)
xfs_btree_check_rec(cur->bc_btnum, rp + i, rp + i + 1);
#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)
xfs_alloc_updkey(cur, &key, level + 1);
/*
* 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 &&
block->bb_rightsib == NULLAGBLOCK &&
recp->ar_blockcount > 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;
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;
xfs_alloc_rcheck(cur);
if (nbno != NULLAGBLOCK) {
*recp = nrec;
*curp = ncur;
} else
xfs_alloc_kcheck(cur);
kmem_check();
return 1;
}
#ifdef XFSDEBUG
/*
* Check key consistency in one btree level, then recurse down to the next.
*/
STATIC void
xfs_alloc_kcheck_btree(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agf_t *agf, /* a.g. freespace header */
xfs_agblock_t bno, /* block number to check */
int level, /* level of the block */
xfs_alloc_key_t *keyp) /* value of expected first key */
{
xfs_alloc_block_t *block; /* btree block pointer */
buf_t *bp; /* buffer for block */
int i; /* loop index */
xfs_alloc_key_t key; /* key value for comparisons */
xfs_alloc_key_t *kp; /* pointer to btree keys */
xfs_alloc_ptr_t *pp; /* pointer to btree index values */
xfs_alloc_rec_t *rp; /* pointer to btree records */
/*
* Get the buffer and block for the one we're checking.
*/
ASSERT(bno != NULLAGBLOCK);
bp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp, agf->agf_seqno,
bno, 0);
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
xfs_btree_check_sblock(cur, block, level);
/*
* If a non-leaf, set up the key pointer & save the first
* key value, if requested.
*/
if (level > 0) {
kp = XFS_ALLOC_KEY_ADDR(block, 1, cur);
if (keyp)
key = *kp;
}
/*
* If a leaf, set up the record pointer and save the key value
* if requested.
*/
else {
rp = XFS_ALLOC_REC_ADDR(block, 1, cur);
if (keyp) {
key.ar_startblock = rp->ar_startblock;
key.ar_blockcount = rp->ar_blockcount;
}
}
/*
* If the caller passed in a matching key, check it.
*/
if (keyp)
ASSERT(bcmp(keyp, &key, sizeof(key)) == 0);
/*
* If this is not yet a leaf, check the next level down recursively.
*/
if (level > 0) {
pp = XFS_ALLOC_PTR_ADDR(block, 1, cur);
if (*pp != NULLAGBLOCK) {
for (i = 1; i <= block->bb_numrecs; i++, pp++, kp++)
xfs_alloc_kcheck_btree(cur, agf, *pp,
level - 1, kp);
}
}
xfs_trans_brelse(cur->bc_tp, bp);
}
#endif
/*
* Log header fields from a btree block.
*/
STATIC void
xfs_alloc_log_block(
xfs_trans_t *tp, /* transaction pointer */
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 int 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);
kmem_check();
}
/*
* Log keys from a btree block (nonleaf).
*/
STATIC void
xfs_alloc_log_keys(
xfs_btree_cur_t *cur, /* btree cursor */
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 = (caddr_t)&kp[kfirst - 1] - (caddr_t)block;
last = ((caddr_t)&kp[klast] - 1) - (caddr_t)block;
xfs_trans_log_buf(cur->bc_tp, bp, first, last);
kmem_check();
}
/*
* Log block pointer fields from a btree block (nonleaf).
*/
STATIC void
xfs_alloc_log_ptrs(
xfs_btree_cur_t *cur, /* btree cursor */
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 = (caddr_t)&pp[pfirst - 1] - (caddr_t)block;
last = ((caddr_t)&pp[plast] - 1) - (caddr_t)block;
xfs_trans_log_buf(cur->bc_tp, bp, first, last);
kmem_check();
}
/*
* Log records from a btree block (leaf).
*/
STATIC void
xfs_alloc_log_recs(
xfs_btree_cur_t *cur, /* btree cursor */
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(p->ar_startblock + p->ar_blockcount <=
agf->agf_length);
}
#endif
first = (caddr_t)&rp[rfirst - 1] - (caddr_t)block;
last = ((caddr_t)&rp[rlast] - 1) - (caddr_t)block;
xfs_trans_log_buf(cur->bc_tp, bp, first, last);
kmem_check();
}
/*
* 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 /* success/failure */
xfs_alloc_lookup(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_lookup_t dir) /* <=, ==, or >= */
{
xfs_agblock_t agbno; /* a.g. relative btree block number */
xfs_agnumber_t agno; /* allocation group number */
xfs_alloc_block_t *block; /* current btree block */
int diff; /* difference for the current key */
int keyno; /* current key number */
int level; /* level in the btree */
xfs_mount_t *mp; /* file system mount point */
xfs_alloc_rcheck(cur);
xfs_alloc_kcheck(cur);
/*
* 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 = agf->agf_seqno;
agbno = 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--) {
buf_t *bp; /* buffer pointer for btree block */
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 && bp->b_blkno != d)
bp = (buf_t *)0;
if (!bp) {
/*
* Need to get a new buffer. Read it, then
* set it in the cursor, releasing the old one.
*/
bp = xfs_trans_read_buf(cur->bc_tp, mp->m_dev, d,
mp->m_bsize, 0);
ASSERT(bp && !geterror(bp));
xfs_btree_setbuf(cur, level, bp);
}
/*
* Point to the btree block, now that we have the buffer.
*/
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
xfs_btree_check_sblock(cur, block, level);
/*
* 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;/* base of keys in block */
xfs_alloc_rec_t *krbase;/* 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 = 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;
kmem_check();
return 0;
}
/*
* Binary search the block.
*/
while (low <= high) {
xfs_extlen_t blockcount; /* key value */
xfs_agblock_t startblock; /* key value */
/*
* 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 = kkp->ar_startblock;
blockcount = kkp->ar_blockcount;
} else {
xfs_alloc_rec_t *krp;
krp = krbase + keyno - 1;
startblock = krp->ar_startblock;
blockcount = 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 = *XFS_ALLOC_PTR_ADDR(block, keyno, cur);
xfs_btree_check_sptr(cur, agbno, level);
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 > block->bb_numrecs &&
block->bb_rightsib != NULLAGBLOCK) {
int i;
cur->bc_ptrs[0] = keyno;
i = xfs_alloc_increment(cur, 0);
ASSERT(i == 1);
kmem_check();
return 1;
}
}
else if (dir == XFS_LOOKUP_LE && diff > 0)
keyno--;
cur->bc_ptrs[0] = keyno;
kmem_check();
/*
* Return if we succeeded or not.
*/
if (keyno == 0 || keyno > block->bb_numrecs)
return 0;
else
return dir != XFS_LOOKUP_EQ || diff == 0;
}
/*
* Move 1 record left from cur/level if possible.
* Update cur to reflect the new path.
*/
STATIC int /* success/failure */
xfs_alloc_lshift(
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level to shift record on */
{
int i; /* loop index */
xfs_alloc_key_t key; /* key value for leaf level upward */
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 */
buf_t *rbp; /* buffer for right (current) block */
xfs_alloc_block_t *right; /* right (current) btree block */
xfs_alloc_key_t *rkp; /* key pointer for right block */
xfs_alloc_ptr_t *rpp; /* address pointer for right block */
xfs_alloc_rec_t *rrp; /* record pointer for right block */
xfs_alloc_rcheck(cur);
/*
* Set up variables for this block as "right".
*/
rbp = cur->bc_bufs[level];
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
xfs_btree_check_sblock(cur, right, level);
/*
* If we've got no left sibling then we can't shift an entry left.
*/
if (right->bb_leftsib == NULLAGBLOCK)
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)
return 0;
/*
* Set up the left neighbor as "left".
*/
lbp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, right->bb_leftsib, 0);
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
xfs_btree_check_sblock(cur, left, level);
/*
* If it's full, it can't take another entry.
*/
if (left->bb_numrecs == XFS_ALLOC_BLOCK_MAXRECS(level, cur)) {
kmem_check();
return 0;
}
nrec = 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);
xfs_btree_check_sptr(cur, *rpp, level);
*lpp = *rpp;
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.
*/
left->bb_numrecs++;
xfs_alloc_log_block(cur->bc_tp, lbp, XFS_BB_NUMRECS);
right->bb_numrecs--;
xfs_alloc_log_block(cur->bc_tp, rbp, XFS_BB_NUMRECS);
/*
* Slide the contents of right down one entry.
*/
if (level > 0) {
for (i = 0; i < right->bb_numrecs; i++) {
rkp[i] = rkp[i + 1];
xfs_btree_check_sptr(cur, rpp[i + 1], level);
rpp[i] = rpp[i + 1];
}
xfs_alloc_log_keys(cur, rbp, 1, right->bb_numrecs);
xfs_alloc_log_ptrs(cur, rbp, 1, right->bb_numrecs);
} else {
for (i = 0; i < right->bb_numrecs; i++)
rrp[i] = rrp[i + 1];
xfs_alloc_log_recs(cur, rbp, 1, right->bb_numrecs);
key.ar_startblock = rrp->ar_startblock;
key.ar_blockcount = rrp->ar_blockcount;
rkp = &key;
}
/*
* Update the parent key values of right.
*/
xfs_alloc_updkey(cur, rkp, level + 1);
/*
* Slide the cursor value left one.
*/
cur->bc_ptrs[level]--;
xfs_alloc_rcheck(cur);
kmem_check();
return 1;
}
/*
* Allocate a new root block, fill it in.
*/
STATIC int /* success/failure */
xfs_alloc_newroot(
xfs_btree_cur_t *cur) /* btree cursor */
{
xfs_agblock_t lbno; /* left block number */
buf_t *lbp; /* left btree buffer */
xfs_alloc_block_t *left; /* left btree block */
xfs_agblock_t nbno; /* new block number */
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 */
buf_t *rbp; /* right btree buffer */
xfs_alloc_block_t *right; /* right btree block */
xfs_alloc_rcheck(cur);
ASSERT(cur->bc_nlevels < XFS_AG_MAXLEVELS(cur->bc_mp));
/*
* Get a buffer from the freelist blocks, for the new root.
*/
nbno = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp);
/*
* None available, we fail.
*/
if (nbno == NULLAGBLOCK)
return 0;
nbp = xfs_btree_read_bufs(cur->bc_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 */
agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
agf->agf_roots[cur->bc_btnum] = nbno;
agf->agf_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);
xfs_btree_check_sblock(cur, left, cur->bc_nlevels - 1);
if (left->bb_rightsib != NULLAGBLOCK) {
/*
* Our block is left, pick up the right block.
*/
lbno = XFS_DADDR_TO_AGBNO(cur->bc_mp, lbp->b_blkno);
rbno = left->bb_rightsib;
rbp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, rbno, 0);
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
xfs_btree_check_sblock(cur, right, cur->bc_nlevels - 1);
nptr = 1;
} else {
/*
* Our block is right, pick up the left block.
*/
rbp = lbp;
right = left;
rbno = XFS_DADDR_TO_AGBNO(cur->bc_mp, rbp->b_blkno);
lbno = right->bb_leftsib;
lbp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, lbno, 0);
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
xfs_btree_check_sblock(cur, left, cur->bc_nlevels - 1);
nptr = 2;
}
/*
* Fill in the new block's btree header and log it.
*/
new->bb_magic = xfs_magics[cur->bc_btnum];
new->bb_level = (__uint16_t)cur->bc_nlevels;
new->bb_numrecs = 2;
new->bb_leftsib = new->bb_rightsib = 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 (left->bb_level > 0) {
kp[0] = *XFS_ALLOC_KEY_ADDR(left, 1, cur);
kp[1] = *XFS_ALLOC_KEY_ADDR(right, 1, cur);
} 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] = lbno;
pp[1] = 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++;
xfs_alloc_rcheck(cur);
xfs_alloc_kcheck(cur);
kmem_check();
return 1;
}
#ifdef XFSDEBUG
/*
* Guts of xfs_alloc_rcheck. For each level in the btree, check
* all its blocks for consistency.
*/
STATIC void
xfs_alloc_rcheck_btree(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agf_t *agf, /* a.g. freespace header */
xfs_agblock_t rbno, /* root block number */
int levels) /* number of levels in the btree */
{
xfs_agblock_t bno; /* current block number being checked */
xfs_agblock_t fbno; /* first block at this level */
xfs_alloc_key_t key; /* space for key value */
int level; /* btree level */
xfs_alloc_rec_t rec; /* space for record value */
void *rp; /* pointer to record or key */
/*
* Starting at the root, check each block at each level of the tree.
*/
rp = levels - 1 ? (void *)&key : (void *)&rec;
for (level = levels - 1, bno = rbno; level >= 0; level--, bno = fbno) {
bno = xfs_alloc_rcheck_btree_block(cur, agf->agf_seqno, bno,
&fbno, rp, level);
while (bno != NULLAGBLOCK) {
ASSERT(bno < agf->agf_length);
bno = xfs_alloc_rcheck_btree_block(cur, agf->agf_seqno,
bno, (xfs_agblock_t *)0, rp, level);
}
}
}
/*
* Check one btree block for record consistency.
* Returns address of the next block to check.
*/
STATIC xfs_agblock_t /* next block to process */
xfs_alloc_rcheck_btree_block(
xfs_btree_cur_t *cur, /* btree cursor */
xfs_agnumber_t agno, /* allocation group number */
xfs_agblock_t bno, /* block number to check */
xfs_agblock_t *fbno, /* output: first block at next level */
void *rec, /* previous record/key value */
int level) /* level of this block */
{
xfs_alloc_block_t *block; /* allocation btree block */
buf_t *bp; /* buffer containing block */
int i; /* loop index */
xfs_alloc_key_t *keyp; /* btree key pointer (input) */
xfs_alloc_key_t *kp; /* btree key pointer in block */
xfs_alloc_ptr_t *pp; /* btree address pointer in block */
xfs_agblock_t rbno; /* return value */
xfs_alloc_rec_t *recp; /* btree record pointer (input) */
xfs_alloc_rec_t *rp; /* btree record pointer in block */
/*
* Grab the buffer and btree block.
*/
bp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp, agno, bno, 0);
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
xfs_btree_check_sblock(cur, block, level);
/*
* If we're supposed to return the first block number for the
* next level, get it.
*/
if (fbno && block->bb_numrecs) {
if (level > 0)
*fbno = *XFS_ALLOC_PTR_ADDR(block, 1, cur);
else
*fbno = NULLAGBLOCK;
}
rbno = block->bb_rightsib;
if (level > 0)
keyp = (xfs_alloc_key_t *)rec;
else
recp = (xfs_alloc_rec_t *)rec;
/*
* Loop over the entries in the btree block.
*/
for (i = 1; i <= block->bb_numrecs; i++) {
/*
* Non-leaf block. Check the key sequence.
*/
if (level > 0) {
kp = XFS_ALLOC_KEY_ADDR(block, i, cur);
if (i == 1 && !fbno)
xfs_btree_check_key(cur->bc_btnum, keyp, kp);
else if (i > 1) {
xfs_btree_check_key(cur->bc_btnum,
(void *)(kp - 1), (void *)kp);
if (i == block->bb_numrecs)
*keyp = *kp;
}
pp = XFS_ALLOC_PTR_ADDR(block, i, cur);
xfs_btree_check_sptr(cur, *pp, level);
}
/*
* Leaf block. Check the record sequence.
*/
else {
rp = XFS_ALLOC_REC_ADDR(block, i, cur);
if (i == 1 && !fbno)
xfs_btree_check_rec(cur->bc_btnum, (void *)recp,
(void *)rp);
else if (i > 1) {
xfs_btree_check_rec(cur->bc_btnum,
(void *)(rp - 1), (void *)rp);
if (i == block->bb_numrecs)
*recp = *rp;
}
}
}
xfs_trans_brelse(cur->bc_tp, bp);
return rbno;
}
#endif
/*
* Move 1 record right from cur/level if possible.
* Update cur to reflect the new path.
*/
STATIC int /* success/failure */
xfs_alloc_rshift(
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level to shift record on */
{
int i; /* loop index */
xfs_alloc_key_t key; /* key value for leaf level upward */
buf_t *lbp; /* buffer for left (current) block */
xfs_alloc_block_t *left; /* left (current) btree block */
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_alloc_rcheck(cur);
/*
* Set up variables for this block as "left".
*/
lbp = cur->bc_bufs[level];
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
xfs_btree_check_sblock(cur, left, level);
/*
* If we've got no right sibling then we can't shift an entry right.
*/
if (left->bb_rightsib == NULLAGBLOCK)
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] >= left->bb_numrecs)
return 0;
/*
* Set up the right neighbor as "right".
*/
rbp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, left->bb_rightsib, 0);
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
xfs_btree_check_sblock(cur, right, level);
/*
* If it's full, it can't take another entry.
*/
if (right->bb_numrecs == XFS_ALLOC_BLOCK_MAXRECS(level, cur)) {
kmem_check();
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, left->bb_numrecs, cur);
lpp = XFS_ALLOC_PTR_ADDR(left, left->bb_numrecs, cur);
rkp = XFS_ALLOC_KEY_ADDR(right, 1, cur);
rpp = XFS_ALLOC_PTR_ADDR(right, 1, cur);
for (i = right->bb_numrecs - 1; i >= 0; i--) {
rkp[i + 1] = rkp[i];
xfs_btree_check_sptr(cur, rpp[i], level);
rpp[i + 1] = rpp[i];
}
xfs_btree_check_sptr(cur, *lpp, level);
*rkp = *lkp;
*rpp = *lpp;
xfs_alloc_log_keys(cur, rbp, 1, right->bb_numrecs + 1);
xfs_alloc_log_ptrs(cur, rbp, 1, 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, left->bb_numrecs, cur);
rrp = XFS_ALLOC_REC_ADDR(right, 1, cur);
for (i = right->bb_numrecs - 1; i >= 0; i--)
rrp[i + 1] = rrp[i];
*rrp = *lrp;
xfs_alloc_log_recs(cur, rbp, 1, 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.
*/
left->bb_numrecs--;
xfs_alloc_log_block(cur->bc_tp, lbp, XFS_BB_NUMRECS);
right->bb_numrecs++;
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.
*/
{
xfs_btree_cur_t *tcur; /* temporary cursor */
tcur = xfs_btree_dup_cursor(cur);
xfs_btree_lastrec(tcur, level);
xfs_alloc_increment(tcur, level);
xfs_alloc_updkey(tcur, rkp, level + 1);
xfs_btree_del_cursor(tcur);
}
xfs_alloc_rcheck(cur);
kmem_check();
return 1;
}
/*
* Split cur/level block in half.
* Return new block number and its first record (to be inserted into parent).
*/
STATIC int /* success/failure */
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 i; /* loop index/record number */
xfs_agblock_t lbno; /* left (current) block number */
buf_t *lbp; /* buffer for left block */
xfs_alloc_block_t *left; /* left (current) btree block */
xfs_agblock_t rbno; /* right (new) block number */
buf_t *rbp; /* buffer for right block */
xfs_alloc_block_t *right; /* right (new) btree block */
xfs_alloc_rcheck(cur);
/*
* Allocate the new block from the freelist.
* If we can't do it, we're toast. Give up.
*/
rbno = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp);
if (rbno == NULLAGBLOCK) {
kmem_check();
return 0;
}
rbp = xfs_btree_read_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);
xfs_btree_check_sblock(cur, left, level);
/*
* Fill in the btree header for the new block.
*/
right->bb_magic = xfs_magics[cur->bc_btnum];
right->bb_level = left->bb_level;
right->bb_numrecs = (__uint16_t)(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 ((left->bb_numrecs & 1) &&
cur->bc_ptrs[level] <= right->bb_numrecs + 1)
right->bb_numrecs++;
i = left->bb_numrecs - 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);
for (i = 0; i < right->bb_numrecs; i++) {
rkp[i] = lkp[i];
xfs_btree_check_sptr(cur, lpp[i], level);
rpp[i] = lpp[i];
}
xfs_alloc_log_keys(cur, rbp, 1, right->bb_numrecs);
xfs_alloc_log_ptrs(cur, rbp, 1, 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);
for (i = 0; i < right->bb_numrecs; i++)
rrp[i] = lrp[i];
xfs_alloc_log_recs(cur, rbp, 1, 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, lbp->b_blkno);
left->bb_numrecs -= right->bb_numrecs;
right->bb_rightsib = left->bb_rightsib;
left->bb_rightsib = rbno;
right->bb_leftsib = 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 (right->bb_rightsib != NULLAGBLOCK) {
xfs_alloc_block_t *rrblock; /* rr btree block */
buf_t *rrbp; /* buffer for rrblock */
rrbp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, right->bb_rightsib, 0);
rrblock = XFS_BUF_TO_ALLOC_BLOCK(rrbp);
xfs_btree_check_sblock(cur, rrblock, level);
rrblock->bb_leftsib = 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] > left->bb_numrecs + 1) {
xfs_btree_setbuf(cur, level, rbp);
cur->bc_ptrs[level] -= left->bb_numrecs;
}
/*
* 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) {
*curp = xfs_btree_dup_cursor(cur);
(*curp)->bc_ptrs[level + 1]++;
}
*bnop = rbno;
xfs_alloc_rcheck(cur);
kmem_check();
return 1;
}
/*
* Update keys at all levels from here to the root along the cursor's path.
*/
STATIC void
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 */
xfs_alloc_rcheck(cur);
/*
* 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 */
buf_t *bp; /* buffer for block */
bp = cur->bc_bufs[level];
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
xfs_btree_check_sblock(cur, block, level);
ptr = cur->bc_ptrs[level];
{
xfs_alloc_key_t *kp; /* ptr to btree block keys */
kp = XFS_ALLOC_KEY_ADDR(block, ptr, cur);
*kp = *keyp;
}
xfs_alloc_log_keys(cur, bp, ptr, ptr);
}
xfs_alloc_rcheck(cur);
kmem_check();
}
/*
* Externally visible routines.
*/
/*
* Decrement cursor by one record at the level.
* For nonzero levels the leaf-ward information is untouched.
*/
int /* success/failure */
xfs_alloc_decrement(
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level in btree, 0 is leaf */
{
xfs_alloc_block_t *block; /* btree block */
int lev; /* btree level */
/*
* Decrement the ptr at this level. If we're still in the block
* then we're done.
*/
if (--cur->bc_ptrs[level] > 0)
return 1;
/*
* Get a pointer to the btree block.
*/
block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[level]);
xfs_btree_check_sblock(cur, block, level);
/*
* If we just went off the left edge of the tree, return failure.
*/
if (block->bb_leftsib == NULLAGBLOCK)
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;
}
/*
* 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 (; lev > level; lev--) {
xfs_agblock_t agbno; /* block number of btree block */
buf_t *bp; /* buffer pointer for block */
block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[lev]);
xfs_btree_check_sblock(cur, block, lev);
agbno = *XFS_ALLOC_PTR_ADDR(block, cur->bc_ptrs[lev], cur);
xfs_btree_setbuf(cur, lev - 1,
bp = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, agbno, 0));
block = XFS_BUF_TO_ALLOC_BLOCK(bp);
xfs_btree_check_sblock(cur, block, lev - 1);
cur->bc_ptrs[lev - 1] = block->bb_numrecs;
}
kmem_check();
return 1;
}
/*
* 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 /* success/failure */
xfs_alloc_delete(
xfs_btree_cur_t *cur) /* btree cursor */
{
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++)
i = xfs_alloc_delrec(cur, level);
xfs_alloc_kcheck(cur);
return i;
}
/*
* Get the data from the pointed-to record.
*/
int /* success/failure */
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 */
{
xfs_alloc_block_t *block; /* btree block */
int ptr; /* record number */
ptr = cur->bc_ptrs[0];
block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[0]);
xfs_btree_check_sblock(cur, block, 0);
/*
* Off the right end or left end, return failure.
*/
if (ptr > block->bb_numrecs || ptr <= 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 = rec->ar_startblock;
*len = rec->ar_blockcount;
}
kmem_check();
return 1;
}
/*
* Increment cursor by one record at the level.
* For nonzero levels the leaf-ward information is untouched.
*/
int /* success/failure */
xfs_alloc_increment(
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level in btree, 0 is leaf */
{
xfs_alloc_block_t *block; /* btree block */
int lev; /* btree level */
/*
* Get a pointer to the btree block.
*/
block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[level]);
xfs_btree_check_sblock(cur, block, level);
/*
* Increment the ptr at this level. If we're still in the block
* then we're done.
*/
if (++cur->bc_ptrs[level] <= block->bb_numrecs)
return 1;
/*
* If we just went off the right edge of the tree, return failure.
*/
if (block->bb_rightsib == NULLAGBLOCK)
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++) {
block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[lev]);
xfs_btree_check_sblock(cur, block, lev);
if (++cur->bc_ptrs[lev] <= block->bb_numrecs)
break;
}
/*
* 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 (; lev > level; lev--) {
xfs_agblock_t agbno; /* block number of btree block */
block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[lev]);
xfs_btree_check_sblock(cur, block, lev);
agbno = *XFS_ALLOC_PTR_ADDR(block, cur->bc_ptrs[lev], cur);
xfs_btree_setbuf(cur, lev - 1,
xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, agbno, 0));
cur->bc_ptrs[lev - 1] = 1;
}
kmem_check();
return 1;
}
/*
* Insert the current record at the point referenced by cur.
* The cursor may be inconsistent on return if splits have been done.
*/
int /* success/failure */
xfs_alloc_insert(
xfs_btree_cur_t *cur) /* btree cursor */
{
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 = cur->bc_rec.a;
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.
*/
i = xfs_alloc_insrec(pcur, level++, &nbno, &nrec, &ncur);
/*
* 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);
}
/*
* If we got a new cursor, switch to it.
*/
if (ncur) {
pcur = ncur;
ncur = (xfs_btree_cur_t *)0;
}
kmem_check();
} while (nbno != NULLAGBLOCK);
return i;
}
#ifdef XFSDEBUG
/*
* Check key consistency in the btree given by cur.
*/
void
xfs_alloc_kcheck(
xfs_btree_cur_t *cur) /* btree cursor */
{
xfs_agf_t *agf; /* allocation group freespace header */
xfs_agblock_t bno; /* block # of btree root */
int levels; /* # of levels in btree */
agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
bno = agf->agf_roots[cur->bc_btnum];
levels = agf->agf_levels[cur->bc_btnum];
ASSERT(levels == cur->bc_nlevels);
xfs_alloc_kcheck_btree(cur, agf, bno, levels - 1, (xfs_alloc_key_t *)0);
}
#endif /* XFSDEBUG */
/*
* Lookup the record equal to [bno, len] in the btree given by cur.
*/
int /* success/failure */
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 */
{
cur->bc_rec.a.ar_startblock = bno;
cur->bc_rec.a.ar_blockcount = len;
return xfs_alloc_lookup(cur, XFS_LOOKUP_EQ);
}
/*
* Lookup the first record greater than or equal to [bno, len]
* in the btree given by cur.
*/
int /* success/failure */
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 */
{
cur->bc_rec.a.ar_startblock = bno;
cur->bc_rec.a.ar_blockcount = len;
return xfs_alloc_lookup(cur, XFS_LOOKUP_GE);
}
/*
* Lookup the first record less than or equal to [bno, len]
* in the btree given by cur.
*/
int /* success/failure */
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 */
{
cur->bc_rec.a.ar_startblock = bno;
cur->bc_rec.a.ar_blockcount = len;
return xfs_alloc_lookup(cur, XFS_LOOKUP_LE);
}
#ifdef XFSDEBUG
/*
* Check consistency in the given btree.
* Checks header consistency and that keys/records are in the right order.
*/
void
xfs_alloc_rcheck(
xfs_btree_cur_t *cur) /* btree cursor */
{
xfs_agf_t *agf; /* a.g. freespace header */
xfs_agblock_t bno; /* block number of btree root */
int levels; /* number of levels in btree */
agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
bno = agf->agf_roots[cur->bc_btnum];
levels = agf->agf_levels[cur->bc_btnum];
xfs_alloc_rcheck_btree(cur, agf, bno, levels);
}
#endif /* XFSDEBUG */
/*
* Update the record referred to by cur, to the value given by [bno, len].
*/
int /* success/failure */
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 ptr; /* current record number (updating) */
/*
* Pick up the a.g. freelist struct and the current block.
*/
xfs_alloc_rcheck(cur);
block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[0]);
xfs_btree_check_sblock(cur, block, 0);
/*
* 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 = bno;
rp->ar_blockcount = 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 &&
block->bb_rightsib == NULLAGBLOCK &&
ptr == block->bb_numrecs) {
xfs_agf_t *agf; /* a.g. freespace header */
agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
agf->agf_longest = 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 = bno;
key.ar_blockcount = len;
xfs_alloc_updkey(cur, &key, 1);
xfs_alloc_rcheck(cur);
xfs_alloc_kcheck(cur);
}
kmem_check();
return 1;
}
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