diff options
author | Christoph Hellwig <hch@infradead.org> | 2008-10-30 16:58:01 +1100 |
---|---|---|
committer | Lachlan McIlroy <lachlan@sgi.com> | 2008-10-30 16:58:01 +1100 |
commit | 91cca5df9bc85efdabfa645f51d54259ed09f4bf (patch) | |
tree | 29032361e21d1210effb72f4018f2a202d6a9fb0 /fs/xfs/xfs_alloc_btree.c | |
parent | d4b3a4b7dd62f2e111d4d0afa9ef3f9b6cd955c0 (diff) |
[XFS] implement generic xfs_btree_delete/delrec
Make the btree delete code generic. Based on a patch from David Chinner
with lots of changes to follow the original btree implementations more
closely. While this loses some of the generic helper routines for
inserting/moving/removing records it also solves some of the one off bugs
in the original code and makes it easier to verify.
SGI-PV: 985583
SGI-Modid: xfs-linux-melb:xfs-kern:32205a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Bill O'Donnell <billodo@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
Diffstat (limited to 'fs/xfs/xfs_alloc_btree.c')
-rw-r--r-- | fs/xfs/xfs_alloc_btree.c | 744 |
1 files changed, 59 insertions, 685 deletions
diff --git a/fs/xfs/xfs_alloc_btree.c b/fs/xfs/xfs_alloc_btree.c index f124ddd91c08..d256b51f913d 100644 --- a/fs/xfs/xfs_alloc_btree.c +++ b/fs/xfs/xfs_alloc_btree.c @@ -40,691 +40,6 @@ #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); - -/* - * 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 */ - int numrecs; - 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. - */ - numrecs = be16_to_cpu(block->bb_numrecs); - if (ptr > 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 < numrecs; i++) { - if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(lpp[i]), level))) - return error; - } -#endif - if (ptr < numrecs) { - memmove(&lkp[ptr - 1], &lkp[ptr], - (numrecs - ptr) * sizeof(*lkp)); - memmove(&lpp[ptr - 1], &lpp[ptr], - (numrecs - ptr) * sizeof(*lpp)); - xfs_alloc_log_ptrs(cur, bp, ptr, numrecs - 1); - xfs_alloc_log_keys(cur, bp, ptr, 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 < numrecs) { - memmove(&lrp[ptr - 1], &lrp[ptr], - (numrecs - ptr) * sizeof(*lrp)); - xfs_alloc_log_recs(cur, bp, ptr, 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. - */ - numrecs--; - block->bb_numrecs = cpu_to_be16(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); - mp = cur->bc_mp; - - if (level == 0 && - cur->bc_btnum == XFS_BTNUM_CNT && - be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK && - ptr > numrecs) { - ASSERT(ptr == numrecs + 1); - /* - * There are still records in the block. Grab the size - * from the last one. - */ - if (numrecs) { - rrp = XFS_ALLOC_REC_ADDR(block, 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 (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_cpu(&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. - */ - error = xfs_alloc_put_freelist(cur->bc_tp, - cur->bc_private.a.agbp, NULL, bno, 1); - if (error) - 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_btree_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_btree_updkey(cur, (union xfs_btree_key *)lkp, level + 1))) - return error; - /* - * If the number of records remaining in the block is at least - * the minimum, we're done. - */ - if (numrecs >= XFS_ALLOC_BLOCK_MINRECS(level, cur)) { - if (level > 0 && (error = xfs_btree_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_btree_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_btree_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_btree_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_btree_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_btree_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_btree_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 + numrecs <= XFS_ALLOC_BLOCK_MAXRECS(level, cur)) { - /* - * Set "right" to be the starting block, - * "left" to be the left neighbor. - */ - rbno = bno; - right = block; - rrecs = be16_to_cpu(right->bb_numrecs); - 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); - lrecs = be16_to_cpu(left->bb_numrecs); - 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 + numrecs <= XFS_ALLOC_BLOCK_MAXRECS(level, cur)) { - /* - * Set "left" to be the starting block, - * "right" to be the right neighbor. - */ - lbno = bno; - left = block; - lrecs = be16_to_cpu(left->bb_numrecs); - 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); - rrecs = be16_to_cpu(right->bb_numrecs); - 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_btree_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, lrecs + 1, cur); - lpp = XFS_ALLOC_PTR_ADDR(left, lrecs + 1, cur); - rkp = XFS_ALLOC_KEY_ADDR(right, 1, cur); - rpp = XFS_ALLOC_PTR_ADDR(right, 1, cur); -#ifdef DEBUG - for (i = 0; i < rrecs; i++) { - if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(rpp[i]), level))) - return error; - } -#endif - memcpy(lkp, rkp, rrecs * sizeof(*lkp)); - memcpy(lpp, rpp, rrecs * sizeof(*lpp)); - xfs_alloc_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs); - xfs_alloc_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs); - } else { - /* - * It's a leaf. Move records. - */ - lrp = XFS_ALLOC_REC_ADDR(left, lrecs + 1, cur); - rrp = XFS_ALLOC_REC_ADDR(right, 1, cur); - memcpy(lrp, rrp, rrecs * sizeof(*lrp)); - xfs_alloc_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs); - } - /* - * 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] += lrecs; - } - /* - * 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_btree_increment(cur, level + 1, &i))) - return error; - /* - * Fix up the number of records in the surviving block. - */ - lrecs += rrecs; - left->bb_numrecs = cpu_to_be16(lrecs); - /* - * 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. - */ - error = xfs_alloc_put_freelist(cur->bc_tp, - cur->bc_private.a.agbp, NULL, rbno, 1); - if (error) - 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; -} - -/* - * 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); -} - - -/* - * Externally visible routines. - */ - -/* - * 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_btree_decrement(cur, level, &i))) - return error; - break; - } - } - } - *stat = i; - return 0; -} /* * Get the data from the pointed-to record. @@ -879,6 +194,7 @@ xfs_allocbt_update_lastrec( struct xfs_agf *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp); xfs_agnumber_t seqno = be32_to_cpu(agf->agf_seqno); __be32 len; + int numrecs; ASSERT(cur->bc_btnum == XFS_BTNUM_CNT); @@ -898,6 +214,22 @@ xfs_allocbt_update_lastrec( return; len = rec->alloc.ar_blockcount; break; + case LASTREC_DELREC: + numrecs = xfs_btree_get_numrecs(block); + if (ptr <= numrecs) + return; + ASSERT(ptr == numrecs + 1); + + if (numrecs) { + xfs_alloc_rec_t *rrp; + + rrp = XFS_ALLOC_REC_ADDR(block, numrecs, cur); + len = rrp->ar_blockcount; + } else { + len = 0; + } + + break; default: ASSERT(0); return; @@ -909,6 +241,14 @@ xfs_allocbt_update_lastrec( } STATIC int +xfs_allocbt_get_minrecs( + struct xfs_btree_cur *cur, + int level) +{ + return cur->bc_mp->m_alloc_mnr[level != 0]; +} + +STATIC int xfs_allocbt_get_maxrecs( struct xfs_btree_cur *cur, int level) @@ -983,6 +323,38 @@ xfs_allocbt_key_diff( return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock; } +STATIC int +xfs_allocbt_kill_root( + struct xfs_btree_cur *cur, + struct xfs_buf *bp, + int level, + union xfs_btree_ptr *newroot) +{ + int error; + + XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); + XFS_BTREE_STATS_INC(cur, killroot); + + /* + * Update the root pointer, decreasing the level by 1 and then + * free the old root. + */ + xfs_allocbt_set_root(cur, newroot, -1); + error = xfs_allocbt_free_block(cur, bp); + if (error) { + XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); + return error; + } + + XFS_BTREE_STATS_INC(cur, free); + + xfs_btree_setbuf(cur, level, NULL); + cur->bc_nlevels--; + + XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); + return 0; +} + #ifdef XFS_BTREE_TRACE ktrace_t *xfs_allocbt_trace_buf; @@ -1055,9 +427,11 @@ static const struct xfs_btree_ops xfs_allocbt_ops = { .dup_cursor = xfs_allocbt_dup_cursor, .set_root = xfs_allocbt_set_root, + .kill_root = xfs_allocbt_kill_root, .alloc_block = xfs_allocbt_alloc_block, .free_block = xfs_allocbt_free_block, .update_lastrec = xfs_allocbt_update_lastrec, + .get_minrecs = xfs_allocbt_get_minrecs, .get_maxrecs = xfs_allocbt_get_maxrecs, .init_key_from_rec = xfs_allocbt_init_key_from_rec, .init_rec_from_key = xfs_allocbt_init_rec_from_key, |