| /* |
| * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc. |
| * All Rights Reserved. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as |
| * published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it would be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| #include "xfs.h" |
| #include "xfs_fs.h" |
| #include "xfs_shared.h" |
| #include "xfs_format.h" |
| #include "xfs_log_format.h" |
| #include "xfs_trans_resv.h" |
| #include "xfs_bit.h" |
| #include "xfs_mount.h" |
| #include "xfs_defer.h" |
| #include "xfs_inode.h" |
| #include "xfs_trans.h" |
| #include "xfs_inode_item.h" |
| #include "xfs_buf_item.h" |
| #include "xfs_btree.h" |
| #include "xfs_error.h" |
| #include "xfs_trace.h" |
| #include "xfs_cksum.h" |
| #include "xfs_alloc.h" |
| #include "xfs_log.h" |
| |
| /* |
| * Cursor allocation zone. |
| */ |
| kmem_zone_t *xfs_btree_cur_zone; |
| |
| /* |
| * Btree magic numbers. |
| */ |
| static const __uint32_t xfs_magics[2][XFS_BTNUM_MAX] = { |
| { XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, 0, XFS_BMAP_MAGIC, XFS_IBT_MAGIC, |
| XFS_FIBT_MAGIC, 0 }, |
| { XFS_ABTB_CRC_MAGIC, XFS_ABTC_CRC_MAGIC, XFS_RMAP_CRC_MAGIC, |
| XFS_BMAP_CRC_MAGIC, XFS_IBT_CRC_MAGIC, XFS_FIBT_CRC_MAGIC, |
| XFS_REFC_CRC_MAGIC } |
| }; |
| #define xfs_btree_magic(cur) \ |
| xfs_magics[!!((cur)->bc_flags & XFS_BTREE_CRC_BLOCKS)][cur->bc_btnum] |
| |
| STATIC int /* error (0 or EFSCORRUPTED) */ |
| xfs_btree_check_lblock( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| struct xfs_btree_block *block, /* btree long form block pointer */ |
| int level, /* level of the btree block */ |
| struct xfs_buf *bp) /* buffer for block, if any */ |
| { |
| int lblock_ok = 1; /* block passes checks */ |
| struct xfs_mount *mp; /* file system mount point */ |
| |
| mp = cur->bc_mp; |
| |
| if (xfs_sb_version_hascrc(&mp->m_sb)) { |
| lblock_ok = lblock_ok && |
| uuid_equal(&block->bb_u.l.bb_uuid, |
| &mp->m_sb.sb_meta_uuid) && |
| block->bb_u.l.bb_blkno == cpu_to_be64( |
| bp ? bp->b_bn : XFS_BUF_DADDR_NULL); |
| } |
| |
| lblock_ok = lblock_ok && |
| be32_to_cpu(block->bb_magic) == xfs_btree_magic(cur) && |
| be16_to_cpu(block->bb_level) == level && |
| be16_to_cpu(block->bb_numrecs) <= |
| cur->bc_ops->get_maxrecs(cur, level) && |
| block->bb_u.l.bb_leftsib && |
| (block->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK) || |
| XFS_FSB_SANITY_CHECK(mp, |
| be64_to_cpu(block->bb_u.l.bb_leftsib))) && |
| block->bb_u.l.bb_rightsib && |
| (block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK) || |
| XFS_FSB_SANITY_CHECK(mp, |
| be64_to_cpu(block->bb_u.l.bb_rightsib))); |
| |
| if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp, |
| XFS_ERRTAG_BTREE_CHECK_LBLOCK, |
| XFS_RANDOM_BTREE_CHECK_LBLOCK))) { |
| if (bp) |
| trace_xfs_btree_corrupt(bp, _RET_IP_); |
| XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp); |
| return -EFSCORRUPTED; |
| } |
| return 0; |
| } |
| |
| STATIC int /* error (0 or EFSCORRUPTED) */ |
| xfs_btree_check_sblock( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| struct xfs_btree_block *block, /* btree short form block pointer */ |
| int level, /* level of the btree block */ |
| struct xfs_buf *bp) /* buffer containing block */ |
| { |
| struct xfs_mount *mp; /* file system mount point */ |
| struct xfs_buf *agbp; /* buffer for ag. freespace struct */ |
| struct xfs_agf *agf; /* ag. freespace structure */ |
| xfs_agblock_t agflen; /* native ag. freespace length */ |
| int sblock_ok = 1; /* block passes checks */ |
| |
| mp = cur->bc_mp; |
| agbp = cur->bc_private.a.agbp; |
| agf = XFS_BUF_TO_AGF(agbp); |
| agflen = be32_to_cpu(agf->agf_length); |
| |
| if (xfs_sb_version_hascrc(&mp->m_sb)) { |
| sblock_ok = sblock_ok && |
| uuid_equal(&block->bb_u.s.bb_uuid, |
| &mp->m_sb.sb_meta_uuid) && |
| block->bb_u.s.bb_blkno == cpu_to_be64( |
| bp ? bp->b_bn : XFS_BUF_DADDR_NULL); |
| } |
| |
| sblock_ok = sblock_ok && |
| be32_to_cpu(block->bb_magic) == xfs_btree_magic(cur) && |
| be16_to_cpu(block->bb_level) == level && |
| be16_to_cpu(block->bb_numrecs) <= |
| cur->bc_ops->get_maxrecs(cur, level) && |
| (block->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) || |
| be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) && |
| block->bb_u.s.bb_leftsib && |
| (block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK) || |
| be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) && |
| block->bb_u.s.bb_rightsib; |
| |
| if (unlikely(XFS_TEST_ERROR(!sblock_ok, mp, |
| XFS_ERRTAG_BTREE_CHECK_SBLOCK, |
| XFS_RANDOM_BTREE_CHECK_SBLOCK))) { |
| if (bp) |
| trace_xfs_btree_corrupt(bp, _RET_IP_); |
| XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp); |
| return -EFSCORRUPTED; |
| } |
| return 0; |
| } |
| |
| /* |
| * Debug routine: check that block header is ok. |
| */ |
| int |
| xfs_btree_check_block( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| struct xfs_btree_block *block, /* generic btree block pointer */ |
| int level, /* level of the btree block */ |
| struct xfs_buf *bp) /* buffer containing block, if any */ |
| { |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| return xfs_btree_check_lblock(cur, block, level, bp); |
| else |
| return xfs_btree_check_sblock(cur, block, level, bp); |
| } |
| |
| /* |
| * Check that (long) pointer is ok. |
| */ |
| int /* error (0 or EFSCORRUPTED) */ |
| xfs_btree_check_lptr( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| xfs_fsblock_t bno, /* btree block disk address */ |
| int level) /* btree block level */ |
| { |
| XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, |
| level > 0 && |
| bno != NULLFSBLOCK && |
| XFS_FSB_SANITY_CHECK(cur->bc_mp, bno)); |
| return 0; |
| } |
| |
| #ifdef DEBUG |
| /* |
| * Check that (short) pointer is ok. |
| */ |
| STATIC int /* error (0 or EFSCORRUPTED) */ |
| xfs_btree_check_sptr( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| xfs_agblock_t bno, /* btree block disk address */ |
| int level) /* btree block level */ |
| { |
| xfs_agblock_t agblocks = cur->bc_mp->m_sb.sb_agblocks; |
| |
| XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, |
| level > 0 && |
| bno != NULLAGBLOCK && |
| bno != 0 && |
| bno < agblocks); |
| return 0; |
| } |
| |
| /* |
| * Check that block ptr is ok. |
| */ |
| STATIC int /* error (0 or EFSCORRUPTED) */ |
| xfs_btree_check_ptr( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| union xfs_btree_ptr *ptr, /* btree block disk address */ |
| int index, /* offset from ptr to check */ |
| int level) /* btree block level */ |
| { |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| return xfs_btree_check_lptr(cur, |
| be64_to_cpu((&ptr->l)[index]), level); |
| } else { |
| return xfs_btree_check_sptr(cur, |
| be32_to_cpu((&ptr->s)[index]), level); |
| } |
| } |
| #endif |
| |
| /* |
| * Calculate CRC on the whole btree block and stuff it into the |
| * long-form btree header. |
| * |
| * Prior to calculting the CRC, pull the LSN out of the buffer log item and put |
| * it into the buffer so recovery knows what the last modification was that made |
| * it to disk. |
| */ |
| void |
| xfs_btree_lblock_calc_crc( |
| struct xfs_buf *bp) |
| { |
| struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp); |
| struct xfs_buf_log_item *bip = bp->b_fspriv; |
| |
| if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb)) |
| return; |
| if (bip) |
| block->bb_u.l.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn); |
| xfs_buf_update_cksum(bp, XFS_BTREE_LBLOCK_CRC_OFF); |
| } |
| |
| bool |
| xfs_btree_lblock_verify_crc( |
| struct xfs_buf *bp) |
| { |
| struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp); |
| struct xfs_mount *mp = bp->b_target->bt_mount; |
| |
| if (xfs_sb_version_hascrc(&mp->m_sb)) { |
| if (!xfs_log_check_lsn(mp, be64_to_cpu(block->bb_u.l.bb_lsn))) |
| return false; |
| return xfs_buf_verify_cksum(bp, XFS_BTREE_LBLOCK_CRC_OFF); |
| } |
| |
| return true; |
| } |
| |
| /* |
| * Calculate CRC on the whole btree block and stuff it into the |
| * short-form btree header. |
| * |
| * Prior to calculting the CRC, pull the LSN out of the buffer log item and put |
| * it into the buffer so recovery knows what the last modification was that made |
| * it to disk. |
| */ |
| void |
| xfs_btree_sblock_calc_crc( |
| struct xfs_buf *bp) |
| { |
| struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp); |
| struct xfs_buf_log_item *bip = bp->b_fspriv; |
| |
| if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb)) |
| return; |
| if (bip) |
| block->bb_u.s.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn); |
| xfs_buf_update_cksum(bp, XFS_BTREE_SBLOCK_CRC_OFF); |
| } |
| |
| bool |
| xfs_btree_sblock_verify_crc( |
| struct xfs_buf *bp) |
| { |
| struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp); |
| struct xfs_mount *mp = bp->b_target->bt_mount; |
| |
| if (xfs_sb_version_hascrc(&mp->m_sb)) { |
| if (!xfs_log_check_lsn(mp, be64_to_cpu(block->bb_u.s.bb_lsn))) |
| return false; |
| return xfs_buf_verify_cksum(bp, XFS_BTREE_SBLOCK_CRC_OFF); |
| } |
| |
| return true; |
| } |
| |
| static int |
| xfs_btree_free_block( |
| struct xfs_btree_cur *cur, |
| struct xfs_buf *bp) |
| { |
| int error; |
| |
| error = cur->bc_ops->free_block(cur, bp); |
| if (!error) { |
| xfs_trans_binval(cur->bc_tp, bp); |
| XFS_BTREE_STATS_INC(cur, free); |
| } |
| return error; |
| } |
| |
| /* |
| * Delete the btree cursor. |
| */ |
| void |
| xfs_btree_del_cursor( |
| xfs_btree_cur_t *cur, /* btree cursor */ |
| int error) /* del because of error */ |
| { |
| int i; /* btree level */ |
| |
| /* |
| * Clear the buffer pointers, and release the buffers. |
| * If we're doing this in the face of an error, we |
| * need to make sure to inspect all of the entries |
| * in the bc_bufs array for buffers to be unlocked. |
| * This is because some of the btree code works from |
| * level n down to 0, and if we get an error along |
| * the way we won't have initialized all the entries |
| * down to 0. |
| */ |
| for (i = 0; i < cur->bc_nlevels; i++) { |
| if (cur->bc_bufs[i]) |
| xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]); |
| else if (!error) |
| break; |
| } |
| /* |
| * Can't free a bmap cursor without having dealt with the |
| * allocated indirect blocks' accounting. |
| */ |
| ASSERT(cur->bc_btnum != XFS_BTNUM_BMAP || |
| cur->bc_private.b.allocated == 0); |
| /* |
| * Free the cursor. |
| */ |
| kmem_zone_free(xfs_btree_cur_zone, cur); |
| } |
| |
| /* |
| * Duplicate the btree cursor. |
| * Allocate a new one, copy the record, re-get the buffers. |
| */ |
| int /* error */ |
| xfs_btree_dup_cursor( |
| xfs_btree_cur_t *cur, /* input cursor */ |
| xfs_btree_cur_t **ncur) /* output cursor */ |
| { |
| xfs_buf_t *bp; /* btree block's buffer pointer */ |
| int error; /* error return value */ |
| int i; /* level number of btree block */ |
| xfs_mount_t *mp; /* mount structure for filesystem */ |
| xfs_btree_cur_t *new; /* new cursor value */ |
| xfs_trans_t *tp; /* transaction pointer, can be NULL */ |
| |
| tp = cur->bc_tp; |
| mp = cur->bc_mp; |
| |
| /* |
| * Allocate a new cursor like the old one. |
| */ |
| new = cur->bc_ops->dup_cursor(cur); |
| |
| /* |
| * Copy the record currently in the cursor. |
| */ |
| new->bc_rec = cur->bc_rec; |
| |
| /* |
| * For each level current, re-get the buffer and copy the ptr value. |
| */ |
| for (i = 0; i < new->bc_nlevels; i++) { |
| new->bc_ptrs[i] = cur->bc_ptrs[i]; |
| new->bc_ra[i] = cur->bc_ra[i]; |
| bp = cur->bc_bufs[i]; |
| if (bp) { |
| error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, |
| XFS_BUF_ADDR(bp), mp->m_bsize, |
| 0, &bp, |
| cur->bc_ops->buf_ops); |
| if (error) { |
| xfs_btree_del_cursor(new, error); |
| *ncur = NULL; |
| return error; |
| } |
| } |
| new->bc_bufs[i] = bp; |
| } |
| *ncur = new; |
| return 0; |
| } |
| |
| /* |
| * XFS btree block layout and addressing: |
| * |
| * There are two types of blocks in the btree: leaf and non-leaf blocks. |
| * |
| * The leaf record start with a header then followed by records containing |
| * the values. A non-leaf block also starts with the same header, and |
| * then first contains lookup keys followed by an equal number of pointers |
| * to the btree blocks at the previous level. |
| * |
| * +--------+-------+-------+-------+-------+-------+-------+ |
| * Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N | |
| * +--------+-------+-------+-------+-------+-------+-------+ |
| * |
| * +--------+-------+-------+-------+-------+-------+-------+ |
| * Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N | |
| * +--------+-------+-------+-------+-------+-------+-------+ |
| * |
| * The header is called struct xfs_btree_block for reasons better left unknown |
| * and comes in different versions for short (32bit) and long (64bit) block |
| * pointers. The record and key structures are defined by the btree instances |
| * and opaque to the btree core. The block pointers are simple disk endian |
| * integers, available in a short (32bit) and long (64bit) variant. |
| * |
| * The helpers below calculate the offset of a given record, key or pointer |
| * into a btree block (xfs_btree_*_offset) or return a pointer to the given |
| * record, key or pointer (xfs_btree_*_addr). Note that all addressing |
| * inside the btree block is done using indices starting at one, not zero! |
| * |
| * If XFS_BTREE_OVERLAPPING is set, then this btree supports keys containing |
| * overlapping intervals. In such a tree, records are still sorted lowest to |
| * highest and indexed by the smallest key value that refers to the record. |
| * However, nodes are different: each pointer has two associated keys -- one |
| * indexing the lowest key available in the block(s) below (the same behavior |
| * as the key in a regular btree) and another indexing the highest key |
| * available in the block(s) below. Because records are /not/ sorted by the |
| * highest key, all leaf block updates require us to compute the highest key |
| * that matches any record in the leaf and to recursively update the high keys |
| * in the nodes going further up in the tree, if necessary. Nodes look like |
| * this: |
| * |
| * +--------+-----+-----+-----+-----+-----+-------+-------+-----+ |
| * Non-Leaf: | header | lo1 | hi1 | lo2 | hi2 | ... | ptr 1 | ptr 2 | ... | |
| * +--------+-----+-----+-----+-----+-----+-------+-------+-----+ |
| * |
| * To perform an interval query on an overlapped tree, perform the usual |
| * depth-first search and use the low and high keys to decide if we can skip |
| * that particular node. If a leaf node is reached, return the records that |
| * intersect the interval. Note that an interval query may return numerous |
| * entries. For a non-overlapped tree, simply search for the record associated |
| * with the lowest key and iterate forward until a non-matching record is |
| * found. Section 14.3 ("Interval Trees") of _Introduction to Algorithms_ by |
| * Cormen, Leiserson, Rivest, and Stein (2nd or 3rd ed. only) discuss this in |
| * more detail. |
| * |
| * Why do we care about overlapping intervals? Let's say you have a bunch of |
| * reverse mapping records on a reflink filesystem: |
| * |
| * 1: +- file A startblock B offset C length D -----------+ |
| * 2: +- file E startblock F offset G length H --------------+ |
| * 3: +- file I startblock F offset J length K --+ |
| * 4: +- file L... --+ |
| * |
| * Now say we want to map block (B+D) into file A at offset (C+D). Ideally, |
| * we'd simply increment the length of record 1. But how do we find the record |
| * that ends at (B+D-1) (i.e. record 1)? A LE lookup of (B+D-1) would return |
| * record 3 because the keys are ordered first by startblock. An interval |
| * query would return records 1 and 2 because they both overlap (B+D-1), and |
| * from that we can pick out record 1 as the appropriate left neighbor. |
| * |
| * In the non-overlapped case you can do a LE lookup and decrement the cursor |
| * because a record's interval must end before the next record. |
| */ |
| |
| /* |
| * Return size of the btree block header for this btree instance. |
| */ |
| static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur) |
| { |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) |
| return XFS_BTREE_LBLOCK_CRC_LEN; |
| return XFS_BTREE_LBLOCK_LEN; |
| } |
| if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) |
| return XFS_BTREE_SBLOCK_CRC_LEN; |
| return XFS_BTREE_SBLOCK_LEN; |
| } |
| |
| /* |
| * Return size of btree block pointers for this btree instance. |
| */ |
| static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur) |
| { |
| return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ? |
| sizeof(__be64) : sizeof(__be32); |
| } |
| |
| /* |
| * Calculate offset of the n-th record in a btree block. |
| */ |
| STATIC size_t |
| xfs_btree_rec_offset( |
| struct xfs_btree_cur *cur, |
| int n) |
| { |
| return xfs_btree_block_len(cur) + |
| (n - 1) * cur->bc_ops->rec_len; |
| } |
| |
| /* |
| * Calculate offset of the n-th key in a btree block. |
| */ |
| STATIC size_t |
| xfs_btree_key_offset( |
| struct xfs_btree_cur *cur, |
| int n) |
| { |
| return xfs_btree_block_len(cur) + |
| (n - 1) * cur->bc_ops->key_len; |
| } |
| |
| /* |
| * Calculate offset of the n-th high key in a btree block. |
| */ |
| STATIC size_t |
| xfs_btree_high_key_offset( |
| struct xfs_btree_cur *cur, |
| int n) |
| { |
| return xfs_btree_block_len(cur) + |
| (n - 1) * cur->bc_ops->key_len + (cur->bc_ops->key_len / 2); |
| } |
| |
| /* |
| * Calculate offset of the n-th block pointer in a btree block. |
| */ |
| STATIC size_t |
| xfs_btree_ptr_offset( |
| struct xfs_btree_cur *cur, |
| int n, |
| int level) |
| { |
| return xfs_btree_block_len(cur) + |
| cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len + |
| (n - 1) * xfs_btree_ptr_len(cur); |
| } |
| |
| /* |
| * Return a pointer to the n-th record in the btree block. |
| */ |
| STATIC union xfs_btree_rec * |
| xfs_btree_rec_addr( |
| struct xfs_btree_cur *cur, |
| int n, |
| struct xfs_btree_block *block) |
| { |
| return (union xfs_btree_rec *) |
| ((char *)block + xfs_btree_rec_offset(cur, n)); |
| } |
| |
| /* |
| * Return a pointer to the n-th key in the btree block. |
| */ |
| STATIC union xfs_btree_key * |
| xfs_btree_key_addr( |
| struct xfs_btree_cur *cur, |
| int n, |
| struct xfs_btree_block *block) |
| { |
| return (union xfs_btree_key *) |
| ((char *)block + xfs_btree_key_offset(cur, n)); |
| } |
| |
| /* |
| * Return a pointer to the n-th high key in the btree block. |
| */ |
| STATIC union xfs_btree_key * |
| xfs_btree_high_key_addr( |
| struct xfs_btree_cur *cur, |
| int n, |
| struct xfs_btree_block *block) |
| { |
| return (union xfs_btree_key *) |
| ((char *)block + xfs_btree_high_key_offset(cur, n)); |
| } |
| |
| /* |
| * Return a pointer to the n-th block pointer in the btree block. |
| */ |
| STATIC union xfs_btree_ptr * |
| xfs_btree_ptr_addr( |
| struct xfs_btree_cur *cur, |
| int n, |
| struct xfs_btree_block *block) |
| { |
| int level = xfs_btree_get_level(block); |
| |
| ASSERT(block->bb_level != 0); |
| |
| return (union xfs_btree_ptr *) |
| ((char *)block + xfs_btree_ptr_offset(cur, n, level)); |
| } |
| |
| /* |
| * Get the root block which is stored in the inode. |
| * |
| * For now this btree implementation assumes the btree root is always |
| * stored in the if_broot field of an inode fork. |
| */ |
| STATIC struct xfs_btree_block * |
| xfs_btree_get_iroot( |
| struct xfs_btree_cur *cur) |
| { |
| struct xfs_ifork *ifp; |
| |
| ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork); |
| return (struct xfs_btree_block *)ifp->if_broot; |
| } |
| |
| /* |
| * Retrieve the block pointer from the cursor at the given level. |
| * This may be an inode btree root or from a buffer. |
| */ |
| STATIC struct xfs_btree_block * /* generic btree block pointer */ |
| xfs_btree_get_block( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| int level, /* level in btree */ |
| struct xfs_buf **bpp) /* buffer containing the block */ |
| { |
| if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| (level == cur->bc_nlevels - 1)) { |
| *bpp = NULL; |
| return xfs_btree_get_iroot(cur); |
| } |
| |
| *bpp = cur->bc_bufs[level]; |
| return XFS_BUF_TO_BLOCK(*bpp); |
| } |
| |
| /* |
| * Get a buffer for the block, return it with no data read. |
| * Long-form addressing. |
| */ |
| xfs_buf_t * /* buffer for fsbno */ |
| xfs_btree_get_bufl( |
| xfs_mount_t *mp, /* file system mount point */ |
| xfs_trans_t *tp, /* transaction pointer */ |
| xfs_fsblock_t fsbno, /* file system block number */ |
| uint lock) /* lock flags for get_buf */ |
| { |
| xfs_daddr_t d; /* real disk block address */ |
| |
| ASSERT(fsbno != NULLFSBLOCK); |
| d = XFS_FSB_TO_DADDR(mp, fsbno); |
| return xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock); |
| } |
| |
| /* |
| * Get a buffer for the block, return it with no data read. |
| * Short-form addressing. |
| */ |
| xfs_buf_t * /* buffer for agno/agbno */ |
| xfs_btree_get_bufs( |
| xfs_mount_t *mp, /* file system mount point */ |
| xfs_trans_t *tp, /* transaction pointer */ |
| xfs_agnumber_t agno, /* allocation group number */ |
| xfs_agblock_t agbno, /* allocation group block number */ |
| uint lock) /* lock flags for get_buf */ |
| { |
| xfs_daddr_t d; /* real disk block address */ |
| |
| ASSERT(agno != NULLAGNUMBER); |
| ASSERT(agbno != NULLAGBLOCK); |
| d = XFS_AGB_TO_DADDR(mp, agno, agbno); |
| return xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock); |
| } |
| |
| /* |
| * Check for the cursor referring to the last block at the given level. |
| */ |
| int /* 1=is last block, 0=not last block */ |
| xfs_btree_islastblock( |
| xfs_btree_cur_t *cur, /* btree cursor */ |
| int level) /* level to check */ |
| { |
| struct xfs_btree_block *block; /* generic btree block pointer */ |
| xfs_buf_t *bp; /* buffer containing block */ |
| |
| block = xfs_btree_get_block(cur, level, &bp); |
| xfs_btree_check_block(cur, block, level, bp); |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK); |
| else |
| return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK); |
| } |
| |
| /* |
| * Change the cursor to point to the first record at the given level. |
| * Other levels are unaffected. |
| */ |
| STATIC int /* success=1, failure=0 */ |
| xfs_btree_firstrec( |
| xfs_btree_cur_t *cur, /* btree cursor */ |
| int level) /* level to change */ |
| { |
| struct xfs_btree_block *block; /* generic btree block pointer */ |
| xfs_buf_t *bp; /* buffer containing block */ |
| |
| /* |
| * Get the block pointer for this level. |
| */ |
| block = xfs_btree_get_block(cur, level, &bp); |
| xfs_btree_check_block(cur, block, level, bp); |
| /* |
| * It's empty, there is no such record. |
| */ |
| if (!block->bb_numrecs) |
| return 0; |
| /* |
| * Set the ptr value to 1, that's the first record/key. |
| */ |
| cur->bc_ptrs[level] = 1; |
| return 1; |
| } |
| |
| /* |
| * Change the cursor to point to the last record in the current block |
| * at the given level. Other levels are unaffected. |
| */ |
| STATIC int /* success=1, failure=0 */ |
| xfs_btree_lastrec( |
| xfs_btree_cur_t *cur, /* btree cursor */ |
| int level) /* level to change */ |
| { |
| struct xfs_btree_block *block; /* generic btree block pointer */ |
| xfs_buf_t *bp; /* buffer containing block */ |
| |
| /* |
| * Get the block pointer for this level. |
| */ |
| block = xfs_btree_get_block(cur, level, &bp); |
| xfs_btree_check_block(cur, block, level, bp); |
| /* |
| * It's empty, there is no such record. |
| */ |
| if (!block->bb_numrecs) |
| return 0; |
| /* |
| * Set the ptr value to numrecs, that's the last record/key. |
| */ |
| cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs); |
| return 1; |
| } |
| |
| /* |
| * Compute first and last byte offsets for the fields given. |
| * Interprets the offsets table, which contains struct field offsets. |
| */ |
| void |
| xfs_btree_offsets( |
| __int64_t fields, /* bitmask of fields */ |
| const short *offsets, /* table of field offsets */ |
| int nbits, /* number of bits to inspect */ |
| int *first, /* output: first byte offset */ |
| int *last) /* output: last byte offset */ |
| { |
| int i; /* current bit number */ |
| __int64_t imask; /* mask for current bit number */ |
| |
| ASSERT(fields != 0); |
| /* |
| * Find the lowest bit, so the first byte offset. |
| */ |
| for (i = 0, imask = 1LL; ; i++, imask <<= 1) { |
| if (imask & fields) { |
| *first = offsets[i]; |
| break; |
| } |
| } |
| /* |
| * Find the highest bit, so the last byte offset. |
| */ |
| for (i = nbits - 1, imask = 1LL << i; ; i--, imask >>= 1) { |
| if (imask & fields) { |
| *last = offsets[i + 1] - 1; |
| break; |
| } |
| } |
| } |
| |
| /* |
| * Get a buffer for the block, return it read in. |
| * Long-form addressing. |
| */ |
| int |
| xfs_btree_read_bufl( |
| struct xfs_mount *mp, /* file system mount point */ |
| struct xfs_trans *tp, /* transaction pointer */ |
| xfs_fsblock_t fsbno, /* file system block number */ |
| uint lock, /* lock flags for read_buf */ |
| struct xfs_buf **bpp, /* buffer for fsbno */ |
| int refval, /* ref count value for buffer */ |
| const struct xfs_buf_ops *ops) |
| { |
| struct xfs_buf *bp; /* return value */ |
| xfs_daddr_t d; /* real disk block address */ |
| int error; |
| |
| ASSERT(fsbno != NULLFSBLOCK); |
| d = XFS_FSB_TO_DADDR(mp, fsbno); |
| error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d, |
| mp->m_bsize, lock, &bp, ops); |
| if (error) |
| return error; |
| if (bp) |
| xfs_buf_set_ref(bp, refval); |
| *bpp = bp; |
| return 0; |
| } |
| |
| /* |
| * Read-ahead the block, don't wait for it, don't return a buffer. |
| * Long-form addressing. |
| */ |
| /* ARGSUSED */ |
| void |
| xfs_btree_reada_bufl( |
| struct xfs_mount *mp, /* file system mount point */ |
| xfs_fsblock_t fsbno, /* file system block number */ |
| xfs_extlen_t count, /* count of filesystem blocks */ |
| const struct xfs_buf_ops *ops) |
| { |
| xfs_daddr_t d; |
| |
| ASSERT(fsbno != NULLFSBLOCK); |
| d = XFS_FSB_TO_DADDR(mp, fsbno); |
| xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops); |
| } |
| |
| /* |
| * Read-ahead the block, don't wait for it, don't return a buffer. |
| * Short-form addressing. |
| */ |
| /* ARGSUSED */ |
| void |
| xfs_btree_reada_bufs( |
| struct xfs_mount *mp, /* file system mount point */ |
| xfs_agnumber_t agno, /* allocation group number */ |
| xfs_agblock_t agbno, /* allocation group block number */ |
| xfs_extlen_t count, /* count of filesystem blocks */ |
| const struct xfs_buf_ops *ops) |
| { |
| xfs_daddr_t d; |
| |
| ASSERT(agno != NULLAGNUMBER); |
| ASSERT(agbno != NULLAGBLOCK); |
| d = XFS_AGB_TO_DADDR(mp, agno, agbno); |
| xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops); |
| } |
| |
| STATIC int |
| xfs_btree_readahead_lblock( |
| struct xfs_btree_cur *cur, |
| int lr, |
| struct xfs_btree_block *block) |
| { |
| int rval = 0; |
| xfs_fsblock_t left = be64_to_cpu(block->bb_u.l.bb_leftsib); |
| xfs_fsblock_t right = be64_to_cpu(block->bb_u.l.bb_rightsib); |
| |
| if ((lr & XFS_BTCUR_LEFTRA) && left != NULLFSBLOCK) { |
| xfs_btree_reada_bufl(cur->bc_mp, left, 1, |
| cur->bc_ops->buf_ops); |
| rval++; |
| } |
| |
| if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLFSBLOCK) { |
| xfs_btree_reada_bufl(cur->bc_mp, right, 1, |
| cur->bc_ops->buf_ops); |
| rval++; |
| } |
| |
| return rval; |
| } |
| |
| STATIC int |
| xfs_btree_readahead_sblock( |
| struct xfs_btree_cur *cur, |
| int lr, |
| struct xfs_btree_block *block) |
| { |
| int rval = 0; |
| xfs_agblock_t left = be32_to_cpu(block->bb_u.s.bb_leftsib); |
| xfs_agblock_t right = be32_to_cpu(block->bb_u.s.bb_rightsib); |
| |
| |
| if ((lr & XFS_BTCUR_LEFTRA) && left != NULLAGBLOCK) { |
| xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno, |
| left, 1, cur->bc_ops->buf_ops); |
| rval++; |
| } |
| |
| if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLAGBLOCK) { |
| xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno, |
| right, 1, cur->bc_ops->buf_ops); |
| rval++; |
| } |
| |
| return rval; |
| } |
| |
| /* |
| * Read-ahead btree blocks, at the given level. |
| * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA. |
| */ |
| STATIC int |
| xfs_btree_readahead( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| int lev, /* level in btree */ |
| int lr) /* left/right bits */ |
| { |
| struct xfs_btree_block *block; |
| |
| /* |
| * No readahead needed if we are at the root level and the |
| * btree root is stored in the inode. |
| */ |
| if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| (lev == cur->bc_nlevels - 1)) |
| return 0; |
| |
| if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev]) |
| return 0; |
| |
| cur->bc_ra[lev] |= lr; |
| block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]); |
| |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| return xfs_btree_readahead_lblock(cur, lr, block); |
| return xfs_btree_readahead_sblock(cur, lr, block); |
| } |
| |
| STATIC xfs_daddr_t |
| xfs_btree_ptr_to_daddr( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_ptr *ptr) |
| { |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| ASSERT(ptr->l != cpu_to_be64(NULLFSBLOCK)); |
| |
| return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l)); |
| } else { |
| ASSERT(cur->bc_private.a.agno != NULLAGNUMBER); |
| ASSERT(ptr->s != cpu_to_be32(NULLAGBLOCK)); |
| |
| return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno, |
| be32_to_cpu(ptr->s)); |
| } |
| } |
| |
| /* |
| * Readahead @count btree blocks at the given @ptr location. |
| * |
| * We don't need to care about long or short form btrees here as we have a |
| * method of converting the ptr directly to a daddr available to us. |
| */ |
| STATIC void |
| xfs_btree_readahead_ptr( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_ptr *ptr, |
| xfs_extlen_t count) |
| { |
| xfs_buf_readahead(cur->bc_mp->m_ddev_targp, |
| xfs_btree_ptr_to_daddr(cur, ptr), |
| cur->bc_mp->m_bsize * count, cur->bc_ops->buf_ops); |
| } |
| |
| /* |
| * Set the buffer for level "lev" in the cursor to bp, releasing |
| * any previous buffer. |
| */ |
| STATIC void |
| xfs_btree_setbuf( |
| xfs_btree_cur_t *cur, /* btree cursor */ |
| int lev, /* level in btree */ |
| xfs_buf_t *bp) /* new buffer to set */ |
| { |
| struct xfs_btree_block *b; /* btree block */ |
| |
| if (cur->bc_bufs[lev]) |
| xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[lev]); |
| cur->bc_bufs[lev] = bp; |
| cur->bc_ra[lev] = 0; |
| |
| b = XFS_BUF_TO_BLOCK(bp); |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| if (b->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK)) |
| cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA; |
| if (b->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK)) |
| cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA; |
| } else { |
| if (b->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK)) |
| cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA; |
| if (b->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK)) |
| cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA; |
| } |
| } |
| |
| STATIC int |
| xfs_btree_ptr_is_null( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_ptr *ptr) |
| { |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| return ptr->l == cpu_to_be64(NULLFSBLOCK); |
| else |
| return ptr->s == cpu_to_be32(NULLAGBLOCK); |
| } |
| |
| STATIC void |
| xfs_btree_set_ptr_null( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_ptr *ptr) |
| { |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| ptr->l = cpu_to_be64(NULLFSBLOCK); |
| else |
| ptr->s = cpu_to_be32(NULLAGBLOCK); |
| } |
| |
| /* |
| * Get/set/init sibling pointers |
| */ |
| STATIC void |
| xfs_btree_get_sibling( |
| struct xfs_btree_cur *cur, |
| struct xfs_btree_block *block, |
| union xfs_btree_ptr *ptr, |
| int lr) |
| { |
| ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB); |
| |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| if (lr == XFS_BB_RIGHTSIB) |
| ptr->l = block->bb_u.l.bb_rightsib; |
| else |
| ptr->l = block->bb_u.l.bb_leftsib; |
| } else { |
| if (lr == XFS_BB_RIGHTSIB) |
| ptr->s = block->bb_u.s.bb_rightsib; |
| else |
| ptr->s = block->bb_u.s.bb_leftsib; |
| } |
| } |
| |
| STATIC void |
| xfs_btree_set_sibling( |
| struct xfs_btree_cur *cur, |
| struct xfs_btree_block *block, |
| union xfs_btree_ptr *ptr, |
| int lr) |
| { |
| ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB); |
| |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| if (lr == XFS_BB_RIGHTSIB) |
| block->bb_u.l.bb_rightsib = ptr->l; |
| else |
| block->bb_u.l.bb_leftsib = ptr->l; |
| } else { |
| if (lr == XFS_BB_RIGHTSIB) |
| block->bb_u.s.bb_rightsib = ptr->s; |
| else |
| block->bb_u.s.bb_leftsib = ptr->s; |
| } |
| } |
| |
| void |
| xfs_btree_init_block_int( |
| struct xfs_mount *mp, |
| struct xfs_btree_block *buf, |
| xfs_daddr_t blkno, |
| __u32 magic, |
| __u16 level, |
| __u16 numrecs, |
| __u64 owner, |
| unsigned int flags) |
| { |
| buf->bb_magic = cpu_to_be32(magic); |
| buf->bb_level = cpu_to_be16(level); |
| buf->bb_numrecs = cpu_to_be16(numrecs); |
| |
| if (flags & XFS_BTREE_LONG_PTRS) { |
| buf->bb_u.l.bb_leftsib = cpu_to_be64(NULLFSBLOCK); |
| buf->bb_u.l.bb_rightsib = cpu_to_be64(NULLFSBLOCK); |
| if (flags & XFS_BTREE_CRC_BLOCKS) { |
| buf->bb_u.l.bb_blkno = cpu_to_be64(blkno); |
| buf->bb_u.l.bb_owner = cpu_to_be64(owner); |
| uuid_copy(&buf->bb_u.l.bb_uuid, &mp->m_sb.sb_meta_uuid); |
| buf->bb_u.l.bb_pad = 0; |
| buf->bb_u.l.bb_lsn = 0; |
| } |
| } else { |
| /* owner is a 32 bit value on short blocks */ |
| __u32 __owner = (__u32)owner; |
| |
| buf->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK); |
| buf->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK); |
| if (flags & XFS_BTREE_CRC_BLOCKS) { |
| buf->bb_u.s.bb_blkno = cpu_to_be64(blkno); |
| buf->bb_u.s.bb_owner = cpu_to_be32(__owner); |
| uuid_copy(&buf->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid); |
| buf->bb_u.s.bb_lsn = 0; |
| } |
| } |
| } |
| |
| void |
| xfs_btree_init_block( |
| struct xfs_mount *mp, |
| struct xfs_buf *bp, |
| __u32 magic, |
| __u16 level, |
| __u16 numrecs, |
| __u64 owner, |
| unsigned int flags) |
| { |
| xfs_btree_init_block_int(mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn, |
| magic, level, numrecs, owner, flags); |
| } |
| |
| STATIC void |
| xfs_btree_init_block_cur( |
| struct xfs_btree_cur *cur, |
| struct xfs_buf *bp, |
| int level, |
| int numrecs) |
| { |
| __u64 owner; |
| |
| /* |
| * we can pull the owner from the cursor right now as the different |
| * owners align directly with the pointer size of the btree. This may |
| * change in future, but is safe for current users of the generic btree |
| * code. |
| */ |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| owner = cur->bc_private.b.ip->i_ino; |
| else |
| owner = cur->bc_private.a.agno; |
| |
| xfs_btree_init_block_int(cur->bc_mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn, |
| xfs_btree_magic(cur), level, numrecs, |
| owner, cur->bc_flags); |
| } |
| |
| /* |
| * Return true if ptr is the last record in the btree and |
| * we need to track updates to this record. The decision |
| * will be further refined in the update_lastrec method. |
| */ |
| STATIC int |
| xfs_btree_is_lastrec( |
| struct xfs_btree_cur *cur, |
| struct xfs_btree_block *block, |
| int level) |
| { |
| union xfs_btree_ptr ptr; |
| |
| if (level > 0) |
| return 0; |
| if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE)) |
| return 0; |
| |
| xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB); |
| if (!xfs_btree_ptr_is_null(cur, &ptr)) |
| return 0; |
| return 1; |
| } |
| |
| STATIC void |
| xfs_btree_buf_to_ptr( |
| struct xfs_btree_cur *cur, |
| struct xfs_buf *bp, |
| union xfs_btree_ptr *ptr) |
| { |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| ptr->l = cpu_to_be64(XFS_DADDR_TO_FSB(cur->bc_mp, |
| XFS_BUF_ADDR(bp))); |
| else { |
| ptr->s = cpu_to_be32(xfs_daddr_to_agbno(cur->bc_mp, |
| XFS_BUF_ADDR(bp))); |
| } |
| } |
| |
| STATIC void |
| xfs_btree_set_refs( |
| struct xfs_btree_cur *cur, |
| struct xfs_buf *bp) |
| { |
| switch (cur->bc_btnum) { |
| case XFS_BTNUM_BNO: |
| case XFS_BTNUM_CNT: |
| xfs_buf_set_ref(bp, XFS_ALLOC_BTREE_REF); |
| break; |
| case XFS_BTNUM_INO: |
| case XFS_BTNUM_FINO: |
| xfs_buf_set_ref(bp, XFS_INO_BTREE_REF); |
| break; |
| case XFS_BTNUM_BMAP: |
| xfs_buf_set_ref(bp, XFS_BMAP_BTREE_REF); |
| break; |
| case XFS_BTNUM_RMAP: |
| xfs_buf_set_ref(bp, XFS_RMAP_BTREE_REF); |
| break; |
| case XFS_BTNUM_REFC: |
| xfs_buf_set_ref(bp, XFS_REFC_BTREE_REF); |
| break; |
| default: |
| ASSERT(0); |
| } |
| } |
| |
| STATIC int |
| xfs_btree_get_buf_block( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_ptr *ptr, |
| int flags, |
| struct xfs_btree_block **block, |
| struct xfs_buf **bpp) |
| { |
| struct xfs_mount *mp = cur->bc_mp; |
| xfs_daddr_t d; |
| |
| /* need to sort out how callers deal with failures first */ |
| ASSERT(!(flags & XBF_TRYLOCK)); |
| |
| d = xfs_btree_ptr_to_daddr(cur, ptr); |
| *bpp = xfs_trans_get_buf(cur->bc_tp, mp->m_ddev_targp, d, |
| mp->m_bsize, flags); |
| |
| if (!*bpp) |
| return -ENOMEM; |
| |
| (*bpp)->b_ops = cur->bc_ops->buf_ops; |
| *block = XFS_BUF_TO_BLOCK(*bpp); |
| return 0; |
| } |
| |
| /* |
| * Read in the buffer at the given ptr and return the buffer and |
| * the block pointer within the buffer. |
| */ |
| STATIC int |
| xfs_btree_read_buf_block( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_ptr *ptr, |
| int flags, |
| struct xfs_btree_block **block, |
| struct xfs_buf **bpp) |
| { |
| struct xfs_mount *mp = cur->bc_mp; |
| xfs_daddr_t d; |
| int error; |
| |
| /* need to sort out how callers deal with failures first */ |
| ASSERT(!(flags & XBF_TRYLOCK)); |
| |
| d = xfs_btree_ptr_to_daddr(cur, ptr); |
| error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d, |
| mp->m_bsize, flags, bpp, |
| cur->bc_ops->buf_ops); |
| if (error) |
| return error; |
| |
| xfs_btree_set_refs(cur, *bpp); |
| *block = XFS_BUF_TO_BLOCK(*bpp); |
| return 0; |
| } |
| |
| /* |
| * Copy keys from one btree block to another. |
| */ |
| STATIC void |
| xfs_btree_copy_keys( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_key *dst_key, |
| union xfs_btree_key *src_key, |
| int numkeys) |
| { |
| ASSERT(numkeys >= 0); |
| memcpy(dst_key, src_key, numkeys * cur->bc_ops->key_len); |
| } |
| |
| /* |
| * Copy records from one btree block to another. |
| */ |
| STATIC void |
| xfs_btree_copy_recs( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_rec *dst_rec, |
| union xfs_btree_rec *src_rec, |
| int numrecs) |
| { |
| ASSERT(numrecs >= 0); |
| memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len); |
| } |
| |
| /* |
| * Copy block pointers from one btree block to another. |
| */ |
| STATIC void |
| xfs_btree_copy_ptrs( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_ptr *dst_ptr, |
| union xfs_btree_ptr *src_ptr, |
| int numptrs) |
| { |
| ASSERT(numptrs >= 0); |
| memcpy(dst_ptr, src_ptr, numptrs * xfs_btree_ptr_len(cur)); |
| } |
| |
| /* |
| * Shift keys one index left/right inside a single btree block. |
| */ |
| STATIC void |
| xfs_btree_shift_keys( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_key *key, |
| int dir, |
| int numkeys) |
| { |
| char *dst_key; |
| |
| ASSERT(numkeys >= 0); |
| ASSERT(dir == 1 || dir == -1); |
| |
| dst_key = (char *)key + (dir * cur->bc_ops->key_len); |
| memmove(dst_key, key, numkeys * cur->bc_ops->key_len); |
| } |
| |
| /* |
| * Shift records one index left/right inside a single btree block. |
| */ |
| STATIC void |
| xfs_btree_shift_recs( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_rec *rec, |
| int dir, |
| int numrecs) |
| { |
| char *dst_rec; |
| |
| ASSERT(numrecs >= 0); |
| ASSERT(dir == 1 || dir == -1); |
| |
| dst_rec = (char *)rec + (dir * cur->bc_ops->rec_len); |
| memmove(dst_rec, rec, numrecs * cur->bc_ops->rec_len); |
| } |
| |
| /* |
| * Shift block pointers one index left/right inside a single btree block. |
| */ |
| STATIC void |
| xfs_btree_shift_ptrs( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_ptr *ptr, |
| int dir, |
| int numptrs) |
| { |
| char *dst_ptr; |
| |
| ASSERT(numptrs >= 0); |
| ASSERT(dir == 1 || dir == -1); |
| |
| dst_ptr = (char *)ptr + (dir * xfs_btree_ptr_len(cur)); |
| memmove(dst_ptr, ptr, numptrs * xfs_btree_ptr_len(cur)); |
| } |
| |
| /* |
| * Log key values from the btree block. |
| */ |
| STATIC void |
| xfs_btree_log_keys( |
| struct xfs_btree_cur *cur, |
| struct xfs_buf *bp, |
| int first, |
| int last) |
| { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGBII(cur, bp, first, last); |
| |
| if (bp) { |
| xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF); |
| xfs_trans_log_buf(cur->bc_tp, bp, |
| xfs_btree_key_offset(cur, first), |
| xfs_btree_key_offset(cur, last + 1) - 1); |
| } else { |
| xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip, |
| xfs_ilog_fbroot(cur->bc_private.b.whichfork)); |
| } |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| } |
| |
| /* |
| * Log record values from the btree block. |
| */ |
| void |
| xfs_btree_log_recs( |
| struct xfs_btree_cur *cur, |
| struct xfs_buf *bp, |
| int first, |
| int last) |
| { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGBII(cur, bp, first, last); |
| |
| xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF); |
| xfs_trans_log_buf(cur->bc_tp, bp, |
| xfs_btree_rec_offset(cur, first), |
| xfs_btree_rec_offset(cur, last + 1) - 1); |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| } |
| |
| /* |
| * Log block pointer fields from a btree block (nonleaf). |
| */ |
| STATIC void |
| xfs_btree_log_ptrs( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| struct xfs_buf *bp, /* buffer containing btree block */ |
| int first, /* index of first pointer to log */ |
| int last) /* index of last pointer to log */ |
| { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGBII(cur, bp, first, last); |
| |
| if (bp) { |
| struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp); |
| int level = xfs_btree_get_level(block); |
| |
| xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF); |
| xfs_trans_log_buf(cur->bc_tp, bp, |
| xfs_btree_ptr_offset(cur, first, level), |
| xfs_btree_ptr_offset(cur, last + 1, level) - 1); |
| } else { |
| xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip, |
| xfs_ilog_fbroot(cur->bc_private.b.whichfork)); |
| } |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| } |
| |
| /* |
| * Log fields from a btree block header. |
| */ |
| void |
| xfs_btree_log_block( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| struct xfs_buf *bp, /* buffer containing btree block */ |
| int fields) /* mask of fields: XFS_BB_... */ |
| { |
| int first; /* first byte offset logged */ |
| int last; /* last byte offset logged */ |
| static const short soffsets[] = { /* table of offsets (short) */ |
| offsetof(struct xfs_btree_block, bb_magic), |
| offsetof(struct xfs_btree_block, bb_level), |
| offsetof(struct xfs_btree_block, bb_numrecs), |
| offsetof(struct xfs_btree_block, bb_u.s.bb_leftsib), |
| offsetof(struct xfs_btree_block, bb_u.s.bb_rightsib), |
| offsetof(struct xfs_btree_block, bb_u.s.bb_blkno), |
| offsetof(struct xfs_btree_block, bb_u.s.bb_lsn), |
| offsetof(struct xfs_btree_block, bb_u.s.bb_uuid), |
| offsetof(struct xfs_btree_block, bb_u.s.bb_owner), |
| offsetof(struct xfs_btree_block, bb_u.s.bb_crc), |
| XFS_BTREE_SBLOCK_CRC_LEN |
| }; |
| static const short loffsets[] = { /* table of offsets (long) */ |
| offsetof(struct xfs_btree_block, bb_magic), |
| offsetof(struct xfs_btree_block, bb_level), |
| offsetof(struct xfs_btree_block, bb_numrecs), |
| offsetof(struct xfs_btree_block, bb_u.l.bb_leftsib), |
| offsetof(struct xfs_btree_block, bb_u.l.bb_rightsib), |
| offsetof(struct xfs_btree_block, bb_u.l.bb_blkno), |
| offsetof(struct xfs_btree_block, bb_u.l.bb_lsn), |
| offsetof(struct xfs_btree_block, bb_u.l.bb_uuid), |
| offsetof(struct xfs_btree_block, bb_u.l.bb_owner), |
| offsetof(struct xfs_btree_block, bb_u.l.bb_crc), |
| offsetof(struct xfs_btree_block, bb_u.l.bb_pad), |
| XFS_BTREE_LBLOCK_CRC_LEN |
| }; |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGBI(cur, bp, fields); |
| |
| if (bp) { |
| int nbits; |
| |
| if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) { |
| /* |
| * We don't log the CRC when updating a btree |
| * block but instead recreate it during log |
| * recovery. As the log buffers have checksums |
| * of their own this is safe and avoids logging a crc |
| * update in a lot of places. |
| */ |
| if (fields == XFS_BB_ALL_BITS) |
| fields = XFS_BB_ALL_BITS_CRC; |
| nbits = XFS_BB_NUM_BITS_CRC; |
| } else { |
| nbits = XFS_BB_NUM_BITS; |
| } |
| xfs_btree_offsets(fields, |
| (cur->bc_flags & XFS_BTREE_LONG_PTRS) ? |
| loffsets : soffsets, |
| nbits, &first, &last); |
| xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF); |
| xfs_trans_log_buf(cur->bc_tp, bp, first, last); |
| } else { |
| xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip, |
| xfs_ilog_fbroot(cur->bc_private.b.whichfork)); |
| } |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| } |
| |
| /* |
| * Increment cursor by one record at the level. |
| * For nonzero levels the leaf-ward information is untouched. |
| */ |
| int /* error */ |
| xfs_btree_increment( |
| struct xfs_btree_cur *cur, |
| int level, |
| int *stat) /* success/failure */ |
| { |
| struct xfs_btree_block *block; |
| union xfs_btree_ptr ptr; |
| struct xfs_buf *bp; |
| int error; /* error return value */ |
| int lev; |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGI(cur, level); |
| |
| ASSERT(level < cur->bc_nlevels); |
| |
| /* Read-ahead to the right at this level. */ |
| xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA); |
| |
| /* Get a pointer to the btree block. */ |
| block = xfs_btree_get_block(cur, level, &bp); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, level, bp); |
| if (error) |
| goto error0; |
| #endif |
| |
| /* We're done if we remain in the block after the increment. */ |
| if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block)) |
| goto out1; |
| |
| /* Fail if we just went off the right edge of the tree. */ |
| xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB); |
| if (xfs_btree_ptr_is_null(cur, &ptr)) |
| goto out0; |
| |
| XFS_BTREE_STATS_INC(cur, increment); |
| |
| /* |
| * March up the tree incrementing pointers. |
| * Stop when we don't go off the right edge of a block. |
| */ |
| for (lev = level + 1; lev < cur->bc_nlevels; lev++) { |
| block = xfs_btree_get_block(cur, lev, &bp); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, lev, bp); |
| if (error) |
| goto error0; |
| #endif |
| |
| if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block)) |
| break; |
| |
| /* Read-ahead the right block for the next loop. */ |
| xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA); |
| } |
| |
| /* |
| * If we went off the root then we are either seriously |
| * confused or have the tree root in an inode. |
| */ |
| if (lev == cur->bc_nlevels) { |
| if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) |
| goto out0; |
| ASSERT(0); |
| error = -EFSCORRUPTED; |
| goto error0; |
| } |
| ASSERT(lev < cur->bc_nlevels); |
| |
| /* |
| * Now walk back down the tree, fixing up the cursor's buffer |
| * pointers and key numbers. |
| */ |
| for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) { |
| union xfs_btree_ptr *ptrp; |
| |
| ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block); |
| --lev; |
| error = xfs_btree_read_buf_block(cur, ptrp, 0, &block, &bp); |
| if (error) |
| goto error0; |
| |
| xfs_btree_setbuf(cur, lev, bp); |
| cur->bc_ptrs[lev] = 1; |
| } |
| out1: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 1; |
| return 0; |
| |
| out0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 0; |
| return 0; |
| |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| /* |
| * Decrement cursor by one record at the level. |
| * For nonzero levels the leaf-ward information is untouched. |
| */ |
| int /* error */ |
| xfs_btree_decrement( |
| struct xfs_btree_cur *cur, |
| int level, |
| int *stat) /* success/failure */ |
| { |
| struct xfs_btree_block *block; |
| xfs_buf_t *bp; |
| int error; /* error return value */ |
| int lev; |
| union xfs_btree_ptr ptr; |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGI(cur, level); |
| |
| ASSERT(level < cur->bc_nlevels); |
| |
| /* Read-ahead to the left at this level. */ |
| xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA); |
| |
| /* We're done if we remain in the block after the decrement. */ |
| if (--cur->bc_ptrs[level] > 0) |
| goto out1; |
| |
| /* Get a pointer to the btree block. */ |
| block = xfs_btree_get_block(cur, level, &bp); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, level, bp); |
| if (error) |
| goto error0; |
| #endif |
| |
| /* Fail if we just went off the left edge of the tree. */ |
| xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB); |
| if (xfs_btree_ptr_is_null(cur, &ptr)) |
| goto out0; |
| |
| XFS_BTREE_STATS_INC(cur, decrement); |
| |
| /* |
| * March up the tree decrementing pointers. |
| * Stop when we don't go off the left edge of a block. |
| */ |
| for (lev = level + 1; lev < cur->bc_nlevels; lev++) { |
| if (--cur->bc_ptrs[lev] > 0) |
| break; |
| /* Read-ahead the left block for the next loop. */ |
| xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA); |
| } |
| |
| /* |
| * If we went off the root then we are seriously confused. |
| * or the root of the tree is in an inode. |
| */ |
| if (lev == cur->bc_nlevels) { |
| if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) |
| goto out0; |
| ASSERT(0); |
| error = -EFSCORRUPTED; |
| goto error0; |
| } |
| ASSERT(lev < cur->bc_nlevels); |
| |
| /* |
| * Now walk back down the tree, fixing up the cursor's buffer |
| * pointers and key numbers. |
| */ |
| for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) { |
| union xfs_btree_ptr *ptrp; |
| |
| ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block); |
| --lev; |
| error = xfs_btree_read_buf_block(cur, ptrp, 0, &block, &bp); |
| if (error) |
| goto error0; |
| xfs_btree_setbuf(cur, lev, bp); |
| cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block); |
| } |
| out1: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 1; |
| return 0; |
| |
| out0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 0; |
| return 0; |
| |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| STATIC int |
| xfs_btree_lookup_get_block( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| int level, /* level in the btree */ |
| union xfs_btree_ptr *pp, /* ptr to btree block */ |
| struct xfs_btree_block **blkp) /* return btree block */ |
| { |
| struct xfs_buf *bp; /* buffer pointer for btree block */ |
| int error = 0; |
| |
| /* special case the root block if in an inode */ |
| if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| (level == cur->bc_nlevels - 1)) { |
| *blkp = xfs_btree_get_iroot(cur); |
| return 0; |
| } |
| |
| /* |
| * If the old buffer at this level for the disk address we are |
| * looking for re-use it. |
| * |
| * Otherwise throw it away and get a new one. |
| */ |
| bp = cur->bc_bufs[level]; |
| if (bp && XFS_BUF_ADDR(bp) == xfs_btree_ptr_to_daddr(cur, pp)) { |
| *blkp = XFS_BUF_TO_BLOCK(bp); |
| return 0; |
| } |
| |
| error = xfs_btree_read_buf_block(cur, pp, 0, blkp, &bp); |
| if (error) |
| return error; |
| |
| xfs_btree_setbuf(cur, level, bp); |
| return 0; |
| } |
| |
| /* |
| * Get current search key. For level 0 we don't actually have a key |
| * structure so we make one up from the record. For all other levels |
| * we just return the right key. |
| */ |
| STATIC union xfs_btree_key * |
| xfs_lookup_get_search_key( |
| struct xfs_btree_cur *cur, |
| int level, |
| int keyno, |
| struct xfs_btree_block *block, |
| union xfs_btree_key *kp) |
| { |
| if (level == 0) { |
| cur->bc_ops->init_key_from_rec(kp, |
| xfs_btree_rec_addr(cur, keyno, block)); |
| return kp; |
| } |
| |
| return xfs_btree_key_addr(cur, keyno, block); |
| } |
| |
| /* |
| * Lookup the record. The cursor is made to point to it, based on dir. |
| * stat is set to 0 if can't find any such record, 1 for success. |
| */ |
| int /* error */ |
| xfs_btree_lookup( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| xfs_lookup_t dir, /* <=, ==, or >= */ |
| int *stat) /* success/failure */ |
| { |
| struct xfs_btree_block *block; /* current btree block */ |
| __int64_t diff; /* difference for the current key */ |
| int error; /* error return value */ |
| int keyno; /* current key number */ |
| int level; /* level in the btree */ |
| union xfs_btree_ptr *pp; /* ptr to btree block */ |
| union xfs_btree_ptr ptr; /* ptr to btree block */ |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGI(cur, dir); |
| |
| XFS_BTREE_STATS_INC(cur, lookup); |
| |
| /* No such thing as a zero-level tree. */ |
| if (cur->bc_nlevels == 0) |
| return -EFSCORRUPTED; |
| |
| block = NULL; |
| keyno = 0; |
| |
| /* initialise start pointer from cursor */ |
| cur->bc_ops->init_ptr_from_cur(cur, &ptr); |
| pp = &ptr; |
| |
| /* |
| * Iterate over each level in the btree, starting at the root. |
| * For each level above the leaves, find the key we need, based |
| * on the lookup record, then follow the corresponding block |
| * pointer down to the next level. |
| */ |
| for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) { |
| /* Get the block we need to do the lookup on. */ |
| error = xfs_btree_lookup_get_block(cur, level, pp, &block); |
| if (error) |
| goto error0; |
| |
| if (diff == 0) { |
| /* |
| * If we already had a key match at a higher level, we |
| * know we need to use the first entry in this block. |
| */ |
| keyno = 1; |
| } else { |
| /* Otherwise search this block. Do a binary search. */ |
| |
| int high; /* high entry number */ |
| int low; /* low entry number */ |
| |
| /* Set low and high entry numbers, 1-based. */ |
| low = 1; |
| high = xfs_btree_get_numrecs(block); |
| if (!high) { |
| /* Block is empty, must be an empty leaf. */ |
| ASSERT(level == 0 && cur->bc_nlevels == 1); |
| |
| cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE; |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 0; |
| return 0; |
| } |
| |
| /* Binary search the block. */ |
| while (low <= high) { |
| union xfs_btree_key key; |
| union xfs_btree_key *kp; |
| |
| XFS_BTREE_STATS_INC(cur, compare); |
| |
| /* keyno is average of low and high. */ |
| keyno = (low + high) >> 1; |
| |
| /* Get current search key */ |
| kp = xfs_lookup_get_search_key(cur, level, |
| keyno, block, &key); |
| |
| /* |
| * Compute difference to get next direction: |
| * - less than, move right |
| * - greater than, move left |
| * - equal, we're done |
| */ |
| diff = cur->bc_ops->key_diff(cur, kp); |
| if (diff < 0) |
| low = keyno + 1; |
| else if (diff > 0) |
| high = keyno - 1; |
| else |
| break; |
| } |
| } |
| |
| /* |
| * If there are more levels, set up for the next level |
| * by getting the block number and filling in the cursor. |
| */ |
| if (level > 0) { |
| /* |
| * If we moved left, need the previous key number, |
| * unless there isn't one. |
| */ |
| if (diff > 0 && --keyno < 1) |
| keyno = 1; |
| pp = xfs_btree_ptr_addr(cur, keyno, block); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_ptr(cur, pp, 0, level); |
| if (error) |
| goto error0; |
| #endif |
| cur->bc_ptrs[level] = keyno; |
| } |
| } |
| |
| /* Done with the search. See if we need to adjust the results. */ |
| if (dir != XFS_LOOKUP_LE && diff < 0) { |
| keyno++; |
| /* |
| * If ge search and we went off the end of the block, but it's |
| * not the last block, we're in the wrong block. |
| */ |
| xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB); |
| if (dir == XFS_LOOKUP_GE && |
| keyno > xfs_btree_get_numrecs(block) && |
| !xfs_btree_ptr_is_null(cur, &ptr)) { |
| int i; |
| |
| cur->bc_ptrs[0] = keyno; |
| error = xfs_btree_increment(cur, 0, &i); |
| if (error) |
| goto error0; |
| XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1); |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 1; |
| return 0; |
| } |
| } else if (dir == XFS_LOOKUP_LE && diff > 0) |
| keyno--; |
| cur->bc_ptrs[0] = keyno; |
| |
| /* Return if we succeeded or not. */ |
| if (keyno == 0 || keyno > xfs_btree_get_numrecs(block)) |
| *stat = 0; |
| else if (dir != XFS_LOOKUP_EQ || diff == 0) |
| *stat = 1; |
| else |
| *stat = 0; |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| return 0; |
| |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| /* Find the high key storage area from a regular key. */ |
| STATIC union xfs_btree_key * |
| xfs_btree_high_key_from_key( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_key *key) |
| { |
| ASSERT(cur->bc_flags & XFS_BTREE_OVERLAPPING); |
| return (union xfs_btree_key *)((char *)key + |
| (cur->bc_ops->key_len / 2)); |
| } |
| |
| /* Determine the low (and high if overlapped) keys of a leaf block */ |
| STATIC void |
| xfs_btree_get_leaf_keys( |
| struct xfs_btree_cur *cur, |
| struct xfs_btree_block *block, |
| union xfs_btree_key *key) |
| { |
| union xfs_btree_key max_hkey; |
| union xfs_btree_key hkey; |
| union xfs_btree_rec *rec; |
| union xfs_btree_key *high; |
| int n; |
| |
| rec = xfs_btree_rec_addr(cur, 1, block); |
| cur->bc_ops->init_key_from_rec(key, rec); |
| |
| if (cur->bc_flags & XFS_BTREE_OVERLAPPING) { |
| |
| cur->bc_ops->init_high_key_from_rec(&max_hkey, rec); |
| for (n = 2; n <= xfs_btree_get_numrecs(block); n++) { |
| rec = xfs_btree_rec_addr(cur, n, block); |
| cur->bc_ops->init_high_key_from_rec(&hkey, rec); |
| if (cur->bc_ops->diff_two_keys(cur, &hkey, &max_hkey) |
| > 0) |
| max_hkey = hkey; |
| } |
| |
| high = xfs_btree_high_key_from_key(cur, key); |
| memcpy(high, &max_hkey, cur->bc_ops->key_len / 2); |
| } |
| } |
| |
| /* Determine the low (and high if overlapped) keys of a node block */ |
| STATIC void |
| xfs_btree_get_node_keys( |
| struct xfs_btree_cur *cur, |
| struct xfs_btree_block *block, |
| union xfs_btree_key *key) |
| { |
| union xfs_btree_key *hkey; |
| union xfs_btree_key *max_hkey; |
| union xfs_btree_key *high; |
| int n; |
| |
| if (cur->bc_flags & XFS_BTREE_OVERLAPPING) { |
| memcpy(key, xfs_btree_key_addr(cur, 1, block), |
| cur->bc_ops->key_len / 2); |
| |
| max_hkey = xfs_btree_high_key_addr(cur, 1, block); |
| for (n = 2; n <= xfs_btree_get_numrecs(block); n++) { |
| hkey = xfs_btree_high_key_addr(cur, n, block); |
| if (cur->bc_ops->diff_two_keys(cur, hkey, max_hkey) > 0) |
| max_hkey = hkey; |
| } |
| |
| high = xfs_btree_high_key_from_key(cur, key); |
| memcpy(high, max_hkey, cur->bc_ops->key_len / 2); |
| } else { |
| memcpy(key, xfs_btree_key_addr(cur, 1, block), |
| cur->bc_ops->key_len); |
| } |
| } |
| |
| /* Derive the keys for any btree block. */ |
| STATIC void |
| xfs_btree_get_keys( |
| struct xfs_btree_cur *cur, |
| struct xfs_btree_block *block, |
| union xfs_btree_key *key) |
| { |
| if (be16_to_cpu(block->bb_level) == 0) |
| xfs_btree_get_leaf_keys(cur, block, key); |
| else |
| xfs_btree_get_node_keys(cur, block, key); |
| } |
| |
| /* |
| * Decide if we need to update the parent keys of a btree block. For |
| * a standard btree this is only necessary if we're updating the first |
| * record/key. For an overlapping btree, we must always update the |
| * keys because the highest key can be in any of the records or keys |
| * in the block. |
| */ |
| static inline bool |
| xfs_btree_needs_key_update( |
| struct xfs_btree_cur *cur, |
| int ptr) |
| { |
| return (cur->bc_flags & XFS_BTREE_OVERLAPPING) || ptr == 1; |
| } |
| |
| /* |
| * Update the low and high parent keys of the given level, progressing |
| * towards the root. If force_all is false, stop if the keys for a given |
| * level do not need updating. |
| */ |
| STATIC int |
| __xfs_btree_updkeys( |
| struct xfs_btree_cur *cur, |
| int level, |
| struct xfs_btree_block *block, |
| struct xfs_buf *bp0, |
| bool force_all) |
| { |
| union xfs_btree_key key; /* keys from current level */ |
| union xfs_btree_key *lkey; /* keys from the next level up */ |
| union xfs_btree_key *hkey; |
| union xfs_btree_key *nlkey; /* keys from the next level up */ |
| union xfs_btree_key *nhkey; |
| struct xfs_buf *bp; |
| int ptr; |
| |
| ASSERT(cur->bc_flags & XFS_BTREE_OVERLAPPING); |
| |
| /* Exit if there aren't any parent levels to update. */ |
| if (level + 1 >= cur->bc_nlevels) |
| return 0; |
| |
| trace_xfs_btree_updkeys(cur, level, bp0); |
| |
| lkey = &key; |
| hkey = xfs_btree_high_key_from_key(cur, lkey); |
| xfs_btree_get_keys(cur, block, lkey); |
| for (level++; level < cur->bc_nlevels; level++) { |
| #ifdef DEBUG |
| int error; |
| #endif |
| block = xfs_btree_get_block(cur, level, &bp); |
| trace_xfs_btree_updkeys(cur, level, bp); |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, level, bp); |
| if (error) { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| #endif |
| ptr = cur->bc_ptrs[level]; |
| nlkey = xfs_btree_key_addr(cur, ptr, block); |
| nhkey = xfs_btree_high_key_addr(cur, ptr, block); |
| if (!force_all && |
| !(cur->bc_ops->diff_two_keys(cur, nlkey, lkey) != 0 || |
| cur->bc_ops->diff_two_keys(cur, nhkey, hkey) != 0)) |
| break; |
| xfs_btree_copy_keys(cur, nlkey, lkey, 1); |
| xfs_btree_log_keys(cur, bp, ptr, ptr); |
| if (level + 1 >= cur->bc_nlevels) |
| break; |
| xfs_btree_get_node_keys(cur, block, lkey); |
| } |
| |
| return 0; |
| } |
| |
| /* Update all the keys from some level in cursor back to the root. */ |
| STATIC int |
| xfs_btree_updkeys_force( |
| struct xfs_btree_cur *cur, |
| int level) |
| { |
| struct xfs_buf *bp; |
| struct xfs_btree_block *block; |
| |
| block = xfs_btree_get_block(cur, level, &bp); |
| return __xfs_btree_updkeys(cur, level, block, bp, true); |
| } |
| |
| /* |
| * Update the parent keys of the given level, progressing towards the root. |
| */ |
| STATIC int |
| xfs_btree_update_keys( |
| struct xfs_btree_cur *cur, |
| int level) |
| { |
| struct xfs_btree_block *block; |
| struct xfs_buf *bp; |
| union xfs_btree_key *kp; |
| union xfs_btree_key key; |
| int ptr; |
| |
| ASSERT(level >= 0); |
| |
| block = xfs_btree_get_block(cur, level, &bp); |
| if (cur->bc_flags & XFS_BTREE_OVERLAPPING) |
| return __xfs_btree_updkeys(cur, level, block, bp, false); |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGIK(cur, level, keyp); |
| |
| /* |
| * 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. |
| */ |
| xfs_btree_get_keys(cur, block, &key); |
| for (level++, ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) { |
| #ifdef DEBUG |
| int error; |
| #endif |
| block = xfs_btree_get_block(cur, level, &bp); |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, level, bp); |
| if (error) { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| #endif |
| ptr = cur->bc_ptrs[level]; |
| kp = xfs_btree_key_addr(cur, ptr, block); |
| xfs_btree_copy_keys(cur, kp, &key, 1); |
| xfs_btree_log_keys(cur, bp, ptr, ptr); |
| } |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| return 0; |
| } |
| |
| /* |
| * Update the record referred to by cur to the value in the |
| * given record. This either works (return 0) or gets an |
| * EFSCORRUPTED error. |
| */ |
| int |
| xfs_btree_update( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_rec *rec) |
| { |
| struct xfs_btree_block *block; |
| struct xfs_buf *bp; |
| int error; |
| int ptr; |
| union xfs_btree_rec *rp; |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGR(cur, rec); |
| |
| /* Pick up the current block. */ |
| block = xfs_btree_get_block(cur, 0, &bp); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, 0, bp); |
| if (error) |
| goto error0; |
| #endif |
| /* Get the address of the rec to be updated. */ |
| ptr = cur->bc_ptrs[0]; |
| rp = xfs_btree_rec_addr(cur, ptr, block); |
| |
| /* Fill in the new contents and log them. */ |
| xfs_btree_copy_recs(cur, rp, rec, 1); |
| xfs_btree_log_recs(cur, bp, ptr, ptr); |
| |
| /* |
| * If we are tracking the last record in the tree and |
| * we are at the far right edge of the tree, update it. |
| */ |
| if (xfs_btree_is_lastrec(cur, block, 0)) { |
| cur->bc_ops->update_lastrec(cur, block, rec, |
| ptr, LASTREC_UPDATE); |
| } |
| |
| /* Pass new key value up to our parent. */ |
| if (xfs_btree_needs_key_update(cur, ptr)) { |
| error = xfs_btree_update_keys(cur, 0); |
| if (error) |
| goto error0; |
| } |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| return 0; |
| |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| /* |
| * Move 1 record left from cur/level if possible. |
| * Update cur to reflect the new path. |
| */ |
| STATIC int /* error */ |
| xfs_btree_lshift( |
| struct xfs_btree_cur *cur, |
| int level, |
| int *stat) /* success/failure */ |
| { |
| struct xfs_buf *lbp; /* left buffer pointer */ |
| struct xfs_btree_block *left; /* left btree block */ |
| int lrecs; /* left record count */ |
| struct xfs_buf *rbp; /* right buffer pointer */ |
| struct xfs_btree_block *right; /* right btree block */ |
| struct xfs_btree_cur *tcur; /* temporary btree cursor */ |
| int rrecs; /* right record count */ |
| union xfs_btree_ptr lptr; /* left btree pointer */ |
| union xfs_btree_key *rkp = NULL; /* right btree key */ |
| union xfs_btree_ptr *rpp = NULL; /* right address pointer */ |
| union xfs_btree_rec *rrp = NULL; /* right record pointer */ |
| int error; /* error return value */ |
| int i; |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGI(cur, level); |
| |
| if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| level == cur->bc_nlevels - 1) |
| goto out0; |
| |
| /* Set up variables for this block as "right". */ |
| right = xfs_btree_get_block(cur, level, &rbp); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, right, level, rbp); |
| if (error) |
| goto error0; |
| #endif |
| |
| /* If we've got no left sibling then we can't shift an entry left. */ |
| xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB); |
| if (xfs_btree_ptr_is_null(cur, &lptr)) |
| goto out0; |
| |
| /* |
| * If the cursor entry is the one that would be moved, don't |
| * do it... it's too complicated. |
| */ |
| if (cur->bc_ptrs[level] <= 1) |
| goto out0; |
| |
| /* Set up the left neighbor as "left". */ |
| error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp); |
| if (error) |
| goto error0; |
| |
| /* If it's full, it can't take another entry. */ |
| lrecs = xfs_btree_get_numrecs(left); |
| if (lrecs == cur->bc_ops->get_maxrecs(cur, level)) |
| goto out0; |
| |
| rrecs = xfs_btree_get_numrecs(right); |
| |
| /* |
| * We add one entry to the left side and remove one for the right side. |
| * Account for it here, the changes will be updated on disk and logged |
| * later. |
| */ |
| lrecs++; |
| rrecs--; |
| |
| XFS_BTREE_STATS_INC(cur, lshift); |
| XFS_BTREE_STATS_ADD(cur, moves, 1); |
| |
| /* |
| * If non-leaf, copy a key and a ptr to the left block. |
| * Log the changes to the left block. |
| */ |
| if (level > 0) { |
| /* It's a non-leaf. Move keys and pointers. */ |
| union xfs_btree_key *lkp; /* left btree key */ |
| union xfs_btree_ptr *lpp; /* left address pointer */ |
| |
| lkp = xfs_btree_key_addr(cur, lrecs, left); |
| rkp = xfs_btree_key_addr(cur, 1, right); |
| |
| lpp = xfs_btree_ptr_addr(cur, lrecs, left); |
| rpp = xfs_btree_ptr_addr(cur, 1, right); |
| #ifdef DEBUG |
| error = xfs_btree_check_ptr(cur, rpp, 0, level); |
| if (error) |
| goto error0; |
| #endif |
| xfs_btree_copy_keys(cur, lkp, rkp, 1); |
| xfs_btree_copy_ptrs(cur, lpp, rpp, 1); |
| |
| xfs_btree_log_keys(cur, lbp, lrecs, lrecs); |
| xfs_btree_log_ptrs(cur, lbp, lrecs, lrecs); |
| |
| ASSERT(cur->bc_ops->keys_inorder(cur, |
| xfs_btree_key_addr(cur, lrecs - 1, left), lkp)); |
| } else { |
| /* It's a leaf. Move records. */ |
| union xfs_btree_rec *lrp; /* left record pointer */ |
| |
| lrp = xfs_btree_rec_addr(cur, lrecs, left); |
| rrp = xfs_btree_rec_addr(cur, 1, right); |
| |
| xfs_btree_copy_recs(cur, lrp, rrp, 1); |
| xfs_btree_log_recs(cur, lbp, lrecs, lrecs); |
| |
| ASSERT(cur->bc_ops->recs_inorder(cur, |
| xfs_btree_rec_addr(cur, lrecs - 1, left), lrp)); |
| } |
| |
| xfs_btree_set_numrecs(left, lrecs); |
| xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS); |
| |
| xfs_btree_set_numrecs(right, rrecs); |
| xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS); |
| |
| /* |
| * Slide the contents of right down one entry. |
| */ |
| XFS_BTREE_STATS_ADD(cur, moves, rrecs - 1); |
| if (level > 0) { |
| /* It's a nonleaf. operate on keys and ptrs */ |
| #ifdef DEBUG |
| int i; /* loop index */ |
| |
| for (i = 0; i < rrecs; i++) { |
| error = xfs_btree_check_ptr(cur, rpp, i + 1, level); |
| if (error) |
| goto error0; |
| } |
| #endif |
| xfs_btree_shift_keys(cur, |
| xfs_btree_key_addr(cur, 2, right), |
| -1, rrecs); |
| xfs_btree_shift_ptrs(cur, |
| xfs_btree_ptr_addr(cur, 2, right), |
| -1, rrecs); |
| |
| xfs_btree_log_keys(cur, rbp, 1, rrecs); |
| xfs_btree_log_ptrs(cur, rbp, 1, rrecs); |
| } else { |
| /* It's a leaf. operate on records */ |
| xfs_btree_shift_recs(cur, |
| xfs_btree_rec_addr(cur, 2, right), |
| -1, rrecs); |
| xfs_btree_log_recs(cur, rbp, 1, rrecs); |
| } |
| |
| /* |
| * Using a temporary cursor, update the parent key values of the |
| * block on the left. |
| */ |
| if (cur->bc_flags & XFS_BTREE_OVERLAPPING) { |
| error = xfs_btree_dup_cursor(cur, &tcur); |
| if (error) |
| goto error0; |
| i = xfs_btree_firstrec(tcur, level); |
| XFS_WANT_CORRUPTED_GOTO(tcur->bc_mp, i == 1, error0); |
| |
| error = xfs_btree_decrement(tcur, level, &i); |
| if (error) |
| goto error1; |
| |
| /* Update the parent high keys of the left block, if needed. */ |
| error = xfs_btree_update_keys(tcur, level); |
| if (error) |
| goto error1; |
| |
| xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); |
| } |
| |
| /* Update the parent keys of the right block. */ |
| error = xfs_btree_update_keys(cur, level); |
| if (error) |
| goto error0; |
| |
| /* Slide the cursor value left one. */ |
| cur->bc_ptrs[level]--; |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 1; |
| return 0; |
| |
| out0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 0; |
| return 0; |
| |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| |
| error1: |
| XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR); |
| xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR); |
| return error; |
| } |
| |
| /* |
| * Move 1 record right from cur/level if possible. |
| * Update cur to reflect the new path. |
| */ |
| STATIC int /* error */ |
| xfs_btree_rshift( |
| struct xfs_btree_cur *cur, |
| int level, |
| int *stat) /* success/failure */ |
| { |
| struct xfs_buf *lbp; /* left buffer pointer */ |
| struct xfs_btree_block *left; /* left btree block */ |
| struct xfs_buf *rbp; /* right buffer pointer */ |
| struct xfs_btree_block *right; /* right btree block */ |
| struct xfs_btree_cur *tcur; /* temporary btree cursor */ |
| union xfs_btree_ptr rptr; /* right block pointer */ |
| union xfs_btree_key *rkp; /* right btree key */ |
| int rrecs; /* right record count */ |
| int lrecs; /* left record count */ |
| int error; /* error return value */ |
| int i; /* loop counter */ |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGI(cur, level); |
| |
| if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| (level == cur->bc_nlevels - 1)) |
| goto out0; |
| |
| /* Set up variables for this block as "left". */ |
| left = xfs_btree_get_block(cur, level, &lbp); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, left, level, lbp); |
| if (error) |
| goto error0; |
| #endif |
| |
| /* If we've got no right sibling then we can't shift an entry right. */ |
| xfs_btree_get_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB); |
| if (xfs_btree_ptr_is_null(cur, &rptr)) |
| goto out0; |
| |
| /* |
| * If the cursor entry is the one that would be moved, don't |
| * do it... it's too complicated. |
| */ |
| lrecs = xfs_btree_get_numrecs(left); |
| if (cur->bc_ptrs[level] >= lrecs) |
| goto out0; |
| |
| /* Set up the right neighbor as "right". */ |
| error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp); |
| if (error) |
| goto error0; |
| |
| /* If it's full, it can't take another entry. */ |
| rrecs = xfs_btree_get_numrecs(right); |
| if (rrecs == cur->bc_ops->get_maxrecs(cur, level)) |
| goto out0; |
| |
| XFS_BTREE_STATS_INC(cur, rshift); |
| XFS_BTREE_STATS_ADD(cur, moves, rrecs); |
| |
| /* |
| * Make a hole at the start of the right neighbor block, then |
| * copy the last left block entry to the hole. |
| */ |
| if (level > 0) { |
| /* It's a nonleaf. make a hole in the keys and ptrs */ |
| union xfs_btree_key *lkp; |
| union xfs_btree_ptr *lpp; |
| union xfs_btree_ptr *rpp; |
| |
| lkp = xfs_btree_key_addr(cur, lrecs, left); |
| lpp = xfs_btree_ptr_addr(cur, lrecs, left); |
| rkp = xfs_btree_key_addr(cur, 1, right); |
| rpp = xfs_btree_ptr_addr(cur, 1, right); |
| |
| #ifdef DEBUG |
| for (i = rrecs - 1; i >= 0; i--) { |
| error = xfs_btree_check_ptr(cur, rpp, i, level); |
| if (error) |
| goto error0; |
| } |
| #endif |
| |
| xfs_btree_shift_keys(cur, rkp, 1, rrecs); |
| xfs_btree_shift_ptrs(cur, rpp, 1, rrecs); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_ptr(cur, lpp, 0, level); |
| if (error) |
| goto error0; |
| #endif |
| |
| /* Now put the new data in, and log it. */ |
| xfs_btree_copy_keys(cur, rkp, lkp, 1); |
| xfs_btree_copy_ptrs(cur, rpp, lpp, 1); |
| |
| xfs_btree_log_keys(cur, rbp, 1, rrecs + 1); |
| xfs_btree_log_ptrs(cur, rbp, 1, rrecs + 1); |
| |
| ASSERT(cur->bc_ops->keys_inorder(cur, rkp, |
| xfs_btree_key_addr(cur, 2, right))); |
| } else { |
| /* It's a leaf. make a hole in the records */ |
| union xfs_btree_rec *lrp; |
| union xfs_btree_rec *rrp; |
| |
| lrp = xfs_btree_rec_addr(cur, lrecs, left); |
| rrp = xfs_btree_rec_addr(cur, 1, right); |
| |
| xfs_btree_shift_recs(cur, rrp, 1, rrecs); |
| |
| /* Now put the new data in, and log it. */ |
| xfs_btree_copy_recs(cur, rrp, lrp, 1); |
| xfs_btree_log_recs(cur, rbp, 1, rrecs + 1); |
| } |
| |
| /* |
| * Decrement and log left's numrecs, bump and log right's numrecs. |
| */ |
| xfs_btree_set_numrecs(left, --lrecs); |
| xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS); |
| |
| xfs_btree_set_numrecs(right, ++rrecs); |
| xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS); |
| |
| /* |
| * Using a temporary cursor, update the parent key values of the |
| * block on the right. |
| */ |
| error = xfs_btree_dup_cursor(cur, &tcur); |
| if (error) |
| goto error0; |
| i = xfs_btree_lastrec(tcur, level); |
| XFS_WANT_CORRUPTED_GOTO(tcur->bc_mp, i == 1, error0); |
| |
| error = xfs_btree_increment(tcur, level, &i); |
| if (error) |
| goto error1; |
| |
| /* Update the parent high keys of the left block, if needed. */ |
| if (cur->bc_flags & XFS_BTREE_OVERLAPPING) { |
| error = xfs_btree_update_keys(cur, level); |
| if (error) |
| goto error1; |
| } |
| |
| /* Update the parent keys of the right block. */ |
| error = xfs_btree_update_keys(tcur, level); |
| if (error) |
| goto error1; |
| |
| xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 1; |
| return 0; |
| |
| out0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 0; |
| return 0; |
| |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| |
| error1: |
| XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR); |
| xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR); |
| return error; |
| } |
| |
| /* |
| * Split cur/level block in half. |
| * Return new block number and the key to its first |
| * record (to be inserted into parent). |
| */ |
| STATIC int /* error */ |
| __xfs_btree_split( |
| struct xfs_btree_cur *cur, |
| int level, |
| union xfs_btree_ptr *ptrp, |
| union xfs_btree_key *key, |
| struct xfs_btree_cur **curp, |
| int *stat) /* success/failure */ |
| { |
| union xfs_btree_ptr lptr; /* left sibling block ptr */ |
| struct xfs_buf *lbp; /* left buffer pointer */ |
| struct xfs_btree_block *left; /* left btree block */ |
| union xfs_btree_ptr rptr; /* right sibling block ptr */ |
| struct xfs_buf *rbp; /* right buffer pointer */ |
| struct xfs_btree_block *right; /* right btree block */ |
| union xfs_btree_ptr rrptr; /* right-right sibling ptr */ |
| struct xfs_buf *rrbp; /* right-right buffer pointer */ |
| struct xfs_btree_block *rrblock; /* right-right btree block */ |
| int lrecs; |
| int rrecs; |
| int src_index; |
| int error; /* error return value */ |
| #ifdef DEBUG |
| int i; |
| #endif |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGIPK(cur, level, *ptrp, key); |
| |
| XFS_BTREE_STATS_INC(cur, split); |
| |
| /* Set up left block (current one). */ |
| left = xfs_btree_get_block(cur, level, &lbp); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, left, level, lbp); |
| if (error) |
| goto error0; |
| #endif |
| |
| xfs_btree_buf_to_ptr(cur, lbp, &lptr); |
| |
| /* Allocate the new block. If we can't do it, we're toast. Give up. */ |
| error = cur->bc_ops->alloc_block(cur, &lptr, &rptr, stat); |
| if (error) |
| goto error0; |
| if (*stat == 0) |
| goto out0; |
| XFS_BTREE_STATS_INC(cur, alloc); |
| |
| /* Set up the new block as "right". */ |
| error = xfs_btree_get_buf_block(cur, &rptr, 0, &right, &rbp); |
| if (error) |
| goto error0; |
| |
| /* Fill in the btree header for the new right block. */ |
| xfs_btree_init_block_cur(cur, rbp, xfs_btree_get_level(left), 0); |
| |
| /* |
| * Split the entries between the old and the new block evenly. |
| * Make sure that if there's an odd number of entries now, that |
| * each new block will have the same number of entries. |
| */ |
| lrecs = xfs_btree_get_numrecs(left); |
| rrecs = lrecs / 2; |
| if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1) |
| rrecs++; |
| src_index = (lrecs - rrecs + 1); |
| |
| XFS_BTREE_STATS_ADD(cur, moves, rrecs); |
| |
| /* Adjust numrecs for the later get_*_keys() calls. */ |
| lrecs -= rrecs; |
| xfs_btree_set_numrecs(left, lrecs); |
| xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs); |
| |
| /* |
| * Copy btree block entries from the left block over to the |
| * new block, the right. Update the right block and log the |
| * changes. |
| */ |
| if (level > 0) { |
| /* It's a non-leaf. Move keys and pointers. */ |
| union xfs_btree_key *lkp; /* left btree key */ |
| union xfs_btree_ptr *lpp; /* left address pointer */ |
| union xfs_btree_key *rkp; /* right btree key */ |
| union xfs_btree_ptr *rpp; /* right address pointer */ |
| |
| lkp = xfs_btree_key_addr(cur, src_index, left); |
| lpp = xfs_btree_ptr_addr(cur, src_index, left); |
| rkp = xfs_btree_key_addr(cur, 1, right); |
| rpp = xfs_btree_ptr_addr(cur, 1, right); |
| |
| #ifdef DEBUG |
| for (i = src_index; i < rrecs; i++) { |
| error = xfs_btree_check_ptr(cur, lpp, i, level); |
| if (error) |
| goto error0; |
| } |
| #endif |
| |
| /* Copy the keys & pointers to the new block. */ |
| xfs_btree_copy_keys(cur, rkp, lkp, rrecs); |
| xfs_btree_copy_ptrs(cur, rpp, lpp, rrecs); |
| |
| xfs_btree_log_keys(cur, rbp, 1, rrecs); |
| xfs_btree_log_ptrs(cur, rbp, 1, rrecs); |
| |
| /* Stash the keys of the new block for later insertion. */ |
| xfs_btree_get_node_keys(cur, right, key); |
| } else { |
| /* It's a leaf. Move records. */ |
| union xfs_btree_rec *lrp; /* left record pointer */ |
| union xfs_btree_rec *rrp; /* right record pointer */ |
| |
| lrp = xfs_btree_rec_addr(cur, src_index, left); |
| rrp = xfs_btree_rec_addr(cur, 1, right); |
| |
| /* Copy records to the new block. */ |
| xfs_btree_copy_recs(cur, rrp, lrp, rrecs); |
| xfs_btree_log_recs(cur, rbp, 1, rrecs); |
| |
| /* Stash the keys of the new block for later insertion. */ |
| xfs_btree_get_leaf_keys(cur, right, key); |
| } |
| |
| /* |
| * Find the left block number by looking in the buffer. |
| * Adjust sibling pointers. |
| */ |
| xfs_btree_get_sibling(cur, left, &rrptr, XFS_BB_RIGHTSIB); |
| xfs_btree_set_sibling(cur, right, &rrptr, XFS_BB_RIGHTSIB); |
| xfs_btree_set_sibling(cur, right, &lptr, XFS_BB_LEFTSIB); |
| xfs_btree_set_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB); |
| |
| xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS); |
| xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB); |
| |
| /* |
| * If there's a block to the new block's right, make that block |
| * point back to right instead of to left. |
| */ |
| if (!xfs_btree_ptr_is_null(cur, &rrptr)) { |
| error = xfs_btree_read_buf_block(cur, &rrptr, |
| 0, &rrblock, &rrbp); |
| if (error) |
| goto error0; |
| xfs_btree_set_sibling(cur, rrblock, &rptr, XFS_BB_LEFTSIB); |
| xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB); |
| } |
| |
| /* Update the parent high keys of the left block, if needed. */ |
| if (cur->bc_flags & XFS_BTREE_OVERLAPPING) { |
| error = xfs_btree_update_keys(cur, level); |
| if (error) |
| goto error0; |
| } |
| |
| /* |
| * If the cursor is really in the right block, move it there. |
| * If it's just pointing past the last entry in left, then we'll |
| * insert there, so don't change anything in that case. |
| */ |
| if (cur->bc_ptrs[level] > lrecs + 1) { |
| xfs_btree_setbuf(cur, level, rbp); |
| cur->bc_ptrs[level] -= lrecs; |
| } |
| /* |
| * If there are more levels, we'll need another cursor which refers |
| * the right block, no matter where this cursor was. |
| */ |
| if (level + 1 < cur->bc_nlevels) { |
| error = xfs_btree_dup_cursor(cur, curp); |
| if (error) |
| goto error0; |
| (*curp)->bc_ptrs[level + 1]++; |
| } |
| *ptrp = rptr; |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 1; |
| return 0; |
| out0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 0; |
| return 0; |
| |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| struct xfs_btree_split_args { |
| struct xfs_btree_cur *cur; |
| int level; |
| union xfs_btree_ptr *ptrp; |
| union xfs_btree_key *key; |
| struct xfs_btree_cur **curp; |
| int *stat; /* success/failure */ |
| int result; |
| bool kswapd; /* allocation in kswapd context */ |
| struct completion *done; |
| struct work_struct work; |
| }; |
| |
| /* |
| * Stack switching interfaces for allocation |
| */ |
| static void |
| xfs_btree_split_worker( |
| struct work_struct *work) |
| { |
| struct xfs_btree_split_args *args = container_of(work, |
| struct xfs_btree_split_args, work); |
| unsigned long pflags; |
| unsigned long new_pflags = PF_FSTRANS; |
| |
| /* |
| * we are in a transaction context here, but may also be doing work |
| * in kswapd context, and hence we may need to inherit that state |
| * temporarily to ensure that we don't block waiting for memory reclaim |
| * in any way. |
| */ |
| if (args->kswapd) |
| new_pflags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD; |
| |
| current_set_flags_nested(&pflags, new_pflags); |
| |
| args->result = __xfs_btree_split(args->cur, args->level, args->ptrp, |
| args->key, args->curp, args->stat); |
| complete(args->done); |
| |
| current_restore_flags_nested(&pflags, new_pflags); |
| } |
| |
| /* |
| * BMBT split requests often come in with little stack to work on. Push |
| * them off to a worker thread so there is lots of stack to use. For the other |
| * btree types, just call directly to avoid the context switch overhead here. |
| */ |
| STATIC int /* error */ |
| xfs_btree_split( |
| struct xfs_btree_cur *cur, |
| int level, |
| union xfs_btree_ptr *ptrp, |
| union xfs_btree_key *key, |
| struct xfs_btree_cur **curp, |
| int *stat) /* success/failure */ |
| { |
| struct xfs_btree_split_args args; |
| DECLARE_COMPLETION_ONSTACK(done); |
| |
| if (cur->bc_btnum != XFS_BTNUM_BMAP) |
| return __xfs_btree_split(cur, level, ptrp, key, curp, stat); |
| |
| args.cur = cur; |
| args.level = level; |
| args.ptrp = ptrp; |
| args.key = key; |
| args.curp = curp; |
| args.stat = stat; |
| args.done = &done; |
| args.kswapd = current_is_kswapd(); |
| INIT_WORK_ONSTACK(&args.work, xfs_btree_split_worker); |
| queue_work(xfs_alloc_wq, &args.work); |
| wait_for_completion(&done); |
| destroy_work_on_stack(&args.work); |
| return args.result; |
| } |
| |
| |
| /* |
| * Copy the old inode root contents into a real block and make the |
| * broot point to it. |
| */ |
| int /* error */ |
| xfs_btree_new_iroot( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| int *logflags, /* logging flags for inode */ |
| int *stat) /* return status - 0 fail */ |
| { |
| struct xfs_buf *cbp; /* buffer for cblock */ |
| struct xfs_btree_block *block; /* btree block */ |
| struct xfs_btree_block *cblock; /* child btree block */ |
| union xfs_btree_key *ckp; /* child key pointer */ |
| union xfs_btree_ptr *cpp; /* child ptr pointer */ |
| union xfs_btree_key *kp; /* pointer to btree key */ |
| union xfs_btree_ptr *pp; /* pointer to block addr */ |
| union xfs_btree_ptr nptr; /* new block addr */ |
| int level; /* btree level */ |
| int error; /* error return code */ |
| #ifdef DEBUG |
| int i; /* loop counter */ |
| #endif |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_STATS_INC(cur, newroot); |
| |
| ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE); |
| |
| level = cur->bc_nlevels - 1; |
| |
| block = xfs_btree_get_iroot(cur); |
| pp = xfs_btree_ptr_addr(cur, 1, block); |
| |
| /* Allocate the new block. If we can't do it, we're toast. Give up. */ |
| error = cur->bc_ops->alloc_block(cur, pp, &nptr, stat); |
| if (error) |
| goto error0; |
| if (*stat == 0) { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| return 0; |
| } |
| XFS_BTREE_STATS_INC(cur, alloc); |
| |
| /* Copy the root into a real block. */ |
| error = xfs_btree_get_buf_block(cur, &nptr, 0, &cblock, &cbp); |
| if (error) |
| goto error0; |
| |
| /* |
| * we can't just memcpy() the root in for CRC enabled btree blocks. |
| * In that case have to also ensure the blkno remains correct |
| */ |
| memcpy(cblock, block, xfs_btree_block_len(cur)); |
| if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) { |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| cblock->bb_u.l.bb_blkno = cpu_to_be64(cbp->b_bn); |
| else |
| cblock->bb_u.s.bb_blkno = cpu_to_be64(cbp->b_bn); |
| } |
| |
| be16_add_cpu(&block->bb_level, 1); |
| xfs_btree_set_numrecs(block, 1); |
| cur->bc_nlevels++; |
| cur->bc_ptrs[level + 1] = 1; |
| |
| kp = xfs_btree_key_addr(cur, 1, block); |
| ckp = xfs_btree_key_addr(cur, 1, cblock); |
| xfs_btree_copy_keys(cur, ckp, kp, xfs_btree_get_numrecs(cblock)); |
| |
| cpp = xfs_btree_ptr_addr(cur, 1, cblock); |
| #ifdef DEBUG |
| for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) { |
| error = xfs_btree_check_ptr(cur, pp, i, level); |
| if (error) |
| goto error0; |
| } |
| #endif |
| xfs_btree_copy_ptrs(cur, cpp, pp, xfs_btree_get_numrecs(cblock)); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_ptr(cur, &nptr, 0, level); |
| if (error) |
| goto error0; |
| #endif |
| xfs_btree_copy_ptrs(cur, pp, &nptr, 1); |
| |
| xfs_iroot_realloc(cur->bc_private.b.ip, |
| 1 - xfs_btree_get_numrecs(cblock), |
| cur->bc_private.b.whichfork); |
| |
| xfs_btree_setbuf(cur, level, cbp); |
| |
| /* |
| * Do all this logging at the end so that |
| * the root is at the right level. |
| */ |
| xfs_btree_log_block(cur, cbp, XFS_BB_ALL_BITS); |
| xfs_btree_log_keys(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs)); |
| xfs_btree_log_ptrs(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs)); |
| |
| *logflags |= |
| XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork); |
| *stat = 1; |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| return 0; |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| /* |
| * Allocate a new root block, fill it in. |
| */ |
| STATIC int /* error */ |
| xfs_btree_new_root( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| int *stat) /* success/failure */ |
| { |
| struct xfs_btree_block *block; /* one half of the old root block */ |
| struct xfs_buf *bp; /* buffer containing block */ |
| int error; /* error return value */ |
| struct xfs_buf *lbp; /* left buffer pointer */ |
| struct xfs_btree_block *left; /* left btree block */ |
| struct xfs_buf *nbp; /* new (root) buffer */ |
| struct xfs_btree_block *new; /* new (root) btree block */ |
| int nptr; /* new value for key index, 1 or 2 */ |
| struct xfs_buf *rbp; /* right buffer pointer */ |
| struct xfs_btree_block *right; /* right btree block */ |
| union xfs_btree_ptr rptr; |
| union xfs_btree_ptr lptr; |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_STATS_INC(cur, newroot); |
| |
| /* initialise our start point from the cursor */ |
| cur->bc_ops->init_ptr_from_cur(cur, &rptr); |
| |
| /* Allocate the new block. If we can't do it, we're toast. Give up. */ |
| error = cur->bc_ops->alloc_block(cur, &rptr, &lptr, stat); |
| if (error) |
| goto error0; |
| if (*stat == 0) |
| goto out0; |
| XFS_BTREE_STATS_INC(cur, alloc); |
| |
| /* Set up the new block. */ |
| error = xfs_btree_get_buf_block(cur, &lptr, 0, &new, &nbp); |
| if (error) |
| goto error0; |
| |
| /* Set the root in the holding structure increasing the level by 1. */ |
| cur->bc_ops->set_root(cur, &lptr, 1); |
| |
| /* |
| * 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. |
| */ |
| block = xfs_btree_get_block(cur, cur->bc_nlevels - 1, &bp); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, cur->bc_nlevels - 1, bp); |
| if (error) |
| goto error0; |
| #endif |
| |
| xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB); |
| if (!xfs_btree_ptr_is_null(cur, &rptr)) { |
| /* Our block is left, pick up the right block. */ |
| lbp = bp; |
| xfs_btree_buf_to_ptr(cur, lbp, &lptr); |
| left = block; |
| error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp); |
| if (error) |
| goto error0; |
| bp = rbp; |
| nptr = 1; |
| } else { |
| /* Our block is right, pick up the left block. */ |
| rbp = bp; |
| xfs_btree_buf_to_ptr(cur, rbp, &rptr); |
| right = block; |
| xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB); |
| error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp); |
| if (error) |
| goto error0; |
| bp = lbp; |
| nptr = 2; |
| } |
| |
| /* Fill in the new block's btree header and log it. */ |
| xfs_btree_init_block_cur(cur, nbp, cur->bc_nlevels, 2); |
| xfs_btree_log_block(cur, nbp, XFS_BB_ALL_BITS); |
| ASSERT(!xfs_btree_ptr_is_null(cur, &lptr) && |
| !xfs_btree_ptr_is_null(cur, &rptr)); |
| |
| /* Fill in the key data in the new root. */ |
| if (xfs_btree_get_level(left) > 0) { |
| /* |
| * Get the keys for the left block's keys and put them directly |
| * in the parent block. Do the same for the right block. |
| */ |
| xfs_btree_get_node_keys(cur, left, |
| xfs_btree_key_addr(cur, 1, new)); |
| xfs_btree_get_node_keys(cur, right, |
| xfs_btree_key_addr(cur, 2, new)); |
| } else { |
| /* |
| * Get the keys for the left block's records and put them |
| * directly in the parent block. Do the same for the right |
| * block. |
| */ |
| xfs_btree_get_leaf_keys(cur, left, |
| xfs_btree_key_addr(cur, 1, new)); |
| xfs_btree_get_leaf_keys(cur, right, |
| xfs_btree_key_addr(cur, 2, new)); |
| } |
| xfs_btree_log_keys(cur, nbp, 1, 2); |
| |
| /* Fill in the pointer data in the new root. */ |
| xfs_btree_copy_ptrs(cur, |
| xfs_btree_ptr_addr(cur, 1, new), &lptr, 1); |
| xfs_btree_copy_ptrs(cur, |
| xfs_btree_ptr_addr(cur, 2, new), &rptr, 1); |
| xfs_btree_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_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 1; |
| return 0; |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| out0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 0; |
| return 0; |
| } |
| |
| STATIC int |
| xfs_btree_make_block_unfull( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| int level, /* btree level */ |
| int numrecs,/* # of recs in block */ |
| int *oindex,/* old tree index */ |
| int *index, /* new tree index */ |
| union xfs_btree_ptr *nptr, /* new btree ptr */ |
| struct xfs_btree_cur **ncur, /* new btree cursor */ |
| union xfs_btree_key *key, /* key of new block */ |
| int *stat) |
| { |
| int error = 0; |
| |
| if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| level == cur->bc_nlevels - 1) { |
| struct xfs_inode *ip = cur->bc_private.b.ip; |
| |
| if (numrecs < cur->bc_ops->get_dmaxrecs(cur, level)) { |
| /* A root block that can be made bigger. */ |
| xfs_iroot_realloc(ip, 1, cur->bc_private.b.whichfork); |
| *stat = 1; |
| } else { |
| /* A root block that needs replacing */ |
| int logflags = 0; |
| |
| error = xfs_btree_new_iroot(cur, &logflags, stat); |
| if (error || *stat == 0) |
| return error; |
| |
| xfs_trans_log_inode(cur->bc_tp, ip, logflags); |
| } |
| |
| return 0; |
| } |
| |
| /* First, try shifting an entry to the right neighbor. */ |
| error = xfs_btree_rshift(cur, level, stat); |
| if (error || *stat) |
| return error; |
| |
| /* Next, try shifting an entry to the left neighbor. */ |
| error = xfs_btree_lshift(cur, level, stat); |
| if (error) |
| return error; |
| |
| if (*stat) { |
| *oindex = *index = cur->bc_ptrs[level]; |
| return 0; |
| } |
| |
| /* |
| * 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. |
| */ |
| error = xfs_btree_split(cur, level, nptr, key, ncur, stat); |
| if (error || *stat == 0) |
| return error; |
| |
| |
| *index = cur->bc_ptrs[level]; |
| return 0; |
| } |
| |
| /* |
| * Insert one record/level. Return information to the caller |
| * allowing the next level up to proceed if necessary. |
| */ |
| STATIC int |
| xfs_btree_insrec( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| int level, /* level to insert record at */ |
| union xfs_btree_ptr *ptrp, /* i/o: block number inserted */ |
| union xfs_btree_rec *rec, /* record to insert */ |
| union xfs_btree_key *key, /* i/o: block key for ptrp */ |
| struct xfs_btree_cur **curp, /* output: new cursor replacing cur */ |
| int *stat) /* success/failure */ |
| { |
| struct xfs_btree_block *block; /* btree block */ |
| struct xfs_buf *bp; /* buffer for block */ |
| union xfs_btree_ptr nptr; /* new block ptr */ |
| struct xfs_btree_cur *ncur; /* new btree cursor */ |
| union xfs_btree_key nkey; /* new block key */ |
| union xfs_btree_key *lkey; |
| int optr; /* old key/record index */ |
| int ptr; /* key/record index */ |
| int numrecs;/* number of records */ |
| int error; /* error return value */ |
| #ifdef DEBUG |
| int i; |
| #endif |
| xfs_daddr_t old_bn; |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, &rec); |
| |
| ncur = NULL; |
| lkey = &nkey; |
| |
| /* |
| * If we have an external root pointer, and we've made it to the |
| * root level, allocate a new root block and we're done. |
| */ |
| if (!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| (level >= cur->bc_nlevels)) { |
| error = xfs_btree_new_root(cur, stat); |
| xfs_btree_set_ptr_null(cur, ptrp); |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| return error; |
| } |
| |
| /* If we're off the left edge, return failure. */ |
| ptr = cur->bc_ptrs[level]; |
| if (ptr == 0) { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 0; |
| return 0; |
| } |
| |
| optr = ptr; |
| |
| XFS_BTREE_STATS_INC(cur, insrec); |
| |
| /* Get pointers to the btree buffer and block. */ |
| block = xfs_btree_get_block(cur, level, &bp); |
| old_bn = bp ? bp->b_bn : XFS_BUF_DADDR_NULL; |
| numrecs = xfs_btree_get_numrecs(block); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, level, bp); |
| if (error) |
| goto error0; |
| |
| /* Check that the new entry is being inserted in the right place. */ |
| if (ptr <= numrecs) { |
| if (level == 0) { |
| ASSERT(cur->bc_ops->recs_inorder(cur, rec, |
| xfs_btree_rec_addr(cur, ptr, block))); |
| } else { |
| ASSERT(cur->bc_ops->keys_inorder(cur, key, |
| xfs_btree_key_addr(cur, ptr, block))); |
| } |
| } |
| #endif |
| |
| /* |
| * If the block is full, we can't insert the new entry until we |
| * make the block un-full. |
| */ |
| xfs_btree_set_ptr_null(cur, &nptr); |
| if (numrecs == cur->bc_ops->get_maxrecs(cur, level)) { |
| error = xfs_btree_make_block_unfull(cur, level, numrecs, |
| &optr, &ptr, &nptr, &ncur, lkey, stat); |
| if (error || *stat == 0) |
| goto error0; |
| } |
| |
| /* |
| * The current block may have changed if the block was |
| * previously full and we have just made space in it. |
| */ |
| block = xfs_btree_get_block(cur, level, &bp); |
| numrecs = xfs_btree_get_numrecs(block); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, level, bp); |
| if (error) |
| return error; |
| #endif |
| |
| /* |
| * At this point we know there's room for our new entry in the block |
| * we're pointing at. |
| */ |
| XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr + 1); |
| |
| if (level > 0) { |
| /* It's a nonleaf. make a hole in the keys and ptrs */ |
| union xfs_btree_key *kp; |
| union xfs_btree_ptr *pp; |
| |
| kp = xfs_btree_key_addr(cur, ptr, block); |
| pp = xfs_btree_ptr_addr(cur, ptr, block); |
| |
| #ifdef DEBUG |
| for (i = numrecs - ptr; i >= 0; i--) { |
| error = xfs_btree_check_ptr(cur, pp, i, level); |
| if (error) |
| return error; |
| } |
| #endif |
| |
| xfs_btree_shift_keys(cur, kp, 1, numrecs - ptr + 1); |
| xfs_btree_shift_ptrs(cur, pp, 1, numrecs - ptr + 1); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_ptr(cur, ptrp, 0, level); |
| if (error) |
| goto error0; |
| #endif |
| |
| /* Now put the new data in, bump numrecs and log it. */ |
| xfs_btree_copy_keys(cur, kp, key, 1); |
| xfs_btree_copy_ptrs(cur, pp, ptrp, 1); |
| numrecs++; |
| xfs_btree_set_numrecs(block, numrecs); |
| xfs_btree_log_ptrs(cur, bp, ptr, numrecs); |
| xfs_btree_log_keys(cur, bp, ptr, numrecs); |
| #ifdef DEBUG |
| if (ptr < numrecs) { |
| ASSERT(cur->bc_ops->keys_inorder(cur, kp, |
| xfs_btree_key_addr(cur, ptr + 1, block))); |
| } |
| #endif |
| } else { |
| /* It's a leaf. make a hole in the records */ |
| union xfs_btree_rec *rp; |
| |
| rp = xfs_btree_rec_addr(cur, ptr, block); |
| |
| xfs_btree_shift_recs(cur, rp, 1, numrecs - ptr + 1); |
| |
| /* Now put the new data in, bump numrecs and log it. */ |
| xfs_btree_copy_recs(cur, rp, rec, 1); |
| xfs_btree_set_numrecs(block, ++numrecs); |
| xfs_btree_log_recs(cur, bp, ptr, numrecs); |
| #ifdef DEBUG |
| if (ptr < numrecs) { |
| ASSERT(cur->bc_ops->recs_inorder(cur, rp, |
| xfs_btree_rec_addr(cur, ptr + 1, block))); |
| } |
| #endif |
| } |
| |
| /* Log the new number of records in the btree header. */ |
| xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS); |
| |
| /* |
| * If we just inserted into a new tree block, we have to |
| * recalculate nkey here because nkey is out of date. |
| * |
| * Otherwise we're just updating an existing block (having shoved |
| * some records into the new tree block), so use the regular key |
| * update mechanism. |
| */ |
| if (bp && bp->b_bn != old_bn) { |
| xfs_btree_get_keys(cur, block, lkey); |
| } else if (xfs_btree_needs_key_update(cur, optr)) { |
| error = xfs_btree_update_keys(cur, level); |
| if (error) |
| goto error0; |
| } |
| |
| /* |
| * If we are tracking the last record in the tree and |
| * we are at the far right edge of the tree, update it. |
| */ |
| if (xfs_btree_is_lastrec(cur, block, level)) { |
| cur->bc_ops->update_lastrec(cur, block, rec, |
| ptr, LASTREC_INSREC); |
| } |
| |
| /* |
| * Return the new block number, if any. |
| * If there is one, give back a record value and a cursor too. |
| */ |
| *ptrp = nptr; |
| if (!xfs_btree_ptr_is_null(cur, &nptr)) { |
| xfs_btree_copy_keys(cur, key, lkey, 1); |
| *curp = ncur; |
| } |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 1; |
| return 0; |
| |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| /* |
| * Insert the record at the point referenced by cur. |
| * |
| * A multi-level split of the tree on insert will invalidate the original |
| * cursor. All callers of this function should assume that the cursor is |
| * no longer valid and revalidate it. |
| */ |
| int |
| xfs_btree_insert( |
| struct xfs_btree_cur *cur, |
| int *stat) |
| { |
| int error; /* error return value */ |
| int i; /* result value, 0 for failure */ |
| int level; /* current level number in btree */ |
| union xfs_btree_ptr nptr; /* new block number (split result) */ |
| struct xfs_btree_cur *ncur; /* new cursor (split result) */ |
| struct xfs_btree_cur *pcur; /* previous level's cursor */ |
| union xfs_btree_key bkey; /* key of block to insert */ |
| union xfs_btree_key *key; |
| union xfs_btree_rec rec; /* record to insert */ |
| |
| level = 0; |
| ncur = NULL; |
| pcur = cur; |
| key = &bkey; |
| |
| xfs_btree_set_ptr_null(cur, &nptr); |
| |
| /* Make a key out of the record data to be inserted, and save it. */ |
| cur->bc_ops->init_rec_from_cur(cur, &rec); |
| cur->bc_ops->init_key_from_rec(key, &rec); |
| |
| /* |
| * 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/nptr into this level of the tree. |
| * Note if we fail, nptr will be null. |
| */ |
| error = xfs_btree_insrec(pcur, level, &nptr, &rec, key, |
| &ncur, &i); |
| if (error) { |
| if (pcur != cur) |
| xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR); |
| goto error0; |
| } |
| |
| XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0); |
| level++; |
| |
| /* |
| * 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 || xfs_btree_ptr_is_null(cur, &nptr))) { |
| /* Save the state from the cursor before we trash it */ |
| if (cur->bc_ops->update_cursor) |
| cur->bc_ops->update_cursor(pcur, cur); |
| 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 = NULL; |
| } |
| } while (!xfs_btree_ptr_is_null(cur, &nptr)); |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = i; |
| return 0; |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| /* |
| * Try to merge a non-leaf block back into the inode root. |
| * |
| * Note: the killroot names comes from the fact that we're effectively |
| * killing the old root block. But because we can't just delete the |
| * inode we have to copy the single block it was pointing to into the |
| * inode. |
| */ |
| STATIC int |
| xfs_btree_kill_iroot( |
| struct xfs_btree_cur *cur) |
| { |
| int whichfork = cur->bc_private.b.whichfork; |
| struct xfs_inode *ip = cur->bc_private.b.ip; |
| struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork); |
| struct xfs_btree_block *block; |
| struct xfs_btree_block *cblock; |
| union xfs_btree_key *kp; |
| union xfs_btree_key *ckp; |
| union xfs_btree_ptr *pp; |
| union xfs_btree_ptr *cpp; |
| struct xfs_buf *cbp; |
| int level; |
| int index; |
| int numrecs; |
| int error; |
| #ifdef DEBUG |
| union xfs_btree_ptr ptr; |
| int i; |
| #endif |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| |
| ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE); |
| ASSERT(cur->bc_nlevels > 1); |
| |
| /* |
| * Don't deal with the root block needs to be a leaf case. |
| * We're just going to turn the thing back into extents anyway. |
| */ |
| level = cur->bc_nlevels - 1; |
| if (level == 1) |
| goto out0; |
| |
| /* |
| * Give up if the root has multiple children. |
| */ |
| block = xfs_btree_get_iroot(cur); |
| if (xfs_btree_get_numrecs(block) != 1) |
| goto out0; |
| |
| cblock = xfs_btree_get_block(cur, level - 1, &cbp); |
| numrecs = xfs_btree_get_numrecs(cblock); |
| |
| /* |
| * Only do this if the next level will fit. |
| * Then the data must be copied up to the inode, |
| * instead of freeing the root you free the next level. |
| */ |
| if (numrecs > cur->bc_ops->get_dmaxrecs(cur, level)) |
| goto out0; |
| |
| XFS_BTREE_STATS_INC(cur, killroot); |
| |
| #ifdef DEBUG |
| xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB); |
| ASSERT(xfs_btree_ptr_is_null(cur, &ptr)); |
| xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB); |
| ASSERT(xfs_btree_ptr_is_null(cur, &ptr)); |
| #endif |
| |
| index = numrecs - cur->bc_ops->get_maxrecs(cur, level); |
| if (index) { |
| xfs_iroot_realloc(cur->bc_private.b.ip, index, |
| cur->bc_private.b.whichfork); |
| block = ifp->if_broot; |
| } |
| |
| be16_add_cpu(&block->bb_numrecs, index); |
| ASSERT(block->bb_numrecs == cblock->bb_numrecs); |
| |
| kp = xfs_btree_key_addr(cur, 1, block); |
| ckp = xfs_btree_key_addr(cur, 1, cblock); |
| xfs_btree_copy_keys(cur, kp, ckp, numrecs); |
| |
| pp = xfs_btree_ptr_addr(cur, 1, block); |
| cpp = xfs_btree_ptr_addr(cur, 1, cblock); |
| #ifdef DEBUG |
| for (i = 0; i < numrecs; i++) { |
| error = xfs_btree_check_ptr(cur, cpp, i, level - 1); |
| if (error) { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| } |
| #endif |
| xfs_btree_copy_ptrs(cur, pp, cpp, numrecs); |
| |
| error = xfs_btree_free_block(cur, cbp); |
| if (error) { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| cur->bc_bufs[level - 1] = NULL; |
| be16_add_cpu(&block->bb_level, -1); |
| xfs_trans_log_inode(cur->bc_tp, ip, |
| XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork)); |
| cur->bc_nlevels--; |
| out0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| return 0; |
| } |
| |
| /* |
| * Kill the current root node, and replace it with it's only child node. |
| */ |
| STATIC int |
| xfs_btree_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. |
| */ |
| cur->bc_ops->set_root(cur, newroot, -1); |
| |
| error = xfs_btree_free_block(cur, bp); |
| if (error) { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| cur->bc_bufs[level] = NULL; |
| cur->bc_ra[level] = 0; |
| cur->bc_nlevels--; |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| return 0; |
| } |
| |
| STATIC int |
| xfs_btree_dec_cursor( |
| struct xfs_btree_cur *cur, |
| int level, |
| int *stat) |
| { |
| int error; |
| int i; |
| |
| if (level > 0) { |
| error = xfs_btree_decrement(cur, level, &i); |
| if (error) |
| return error; |
| } |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 1; |
| return 0; |
| } |
| |
| /* |
| * Single level of the btree 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_btree_delrec( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| int level, /* level removing record from */ |
| int *stat) /* fail/done/go-on */ |
| { |
| struct xfs_btree_block *block; /* btree block */ |
| union xfs_btree_ptr cptr; /* current block ptr */ |
| struct xfs_buf *bp; /* buffer for block */ |
| int error; /* error return value */ |
| int i; /* loop counter */ |
| union xfs_btree_ptr lptr; /* left sibling block ptr */ |
| struct xfs_buf *lbp; /* left buffer pointer */ |
| struct xfs_btree_block *left; /* left btree block */ |
| int lrecs = 0; /* left record count */ |
| int ptr; /* key/record index */ |
| union xfs_btree_ptr rptr; /* right sibling block ptr */ |
| struct xfs_buf *rbp; /* right buffer pointer */ |
| struct xfs_btree_block *right; /* right btree block */ |
| struct xfs_btree_block *rrblock; /* right-right btree block */ |
| struct xfs_buf *rrbp; /* right-right buffer pointer */ |
| int rrecs = 0; /* right record count */ |
| struct xfs_btree_cur *tcur; /* temporary btree cursor */ |
| int numrecs; /* temporary numrec count */ |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| XFS_BTREE_TRACE_ARGI(cur, level); |
| |
| tcur = NULL; |
| |
| /* Get the index of the entry being deleted, check for nothing there. */ |
| ptr = cur->bc_ptrs[level]; |
| if (ptr == 0) { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 0; |
| return 0; |
| } |
| |
| /* Get the buffer & block containing the record or key/ptr. */ |
| block = xfs_btree_get_block(cur, level, &bp); |
| numrecs = xfs_btree_get_numrecs(block); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, level, bp); |
| if (error) |
| goto error0; |
| #endif |
| |
| /* Fail if we're off the end of the block. */ |
| if (ptr > numrecs) { |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 0; |
| return 0; |
| } |
| |
| XFS_BTREE_STATS_INC(cur, delrec); |
| XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr); |
| |
| /* Excise the entries being deleted. */ |
| if (level > 0) { |
| /* It's a nonleaf. operate on keys and ptrs */ |
| union xfs_btree_key *lkp; |
| union xfs_btree_ptr *lpp; |
| |
| lkp = xfs_btree_key_addr(cur, ptr + 1, block); |
| lpp = xfs_btree_ptr_addr(cur, ptr + 1, block); |
| |
| #ifdef DEBUG |
| for (i = 0; i < numrecs - ptr; i++) { |
| error = xfs_btree_check_ptr(cur, lpp, i, level); |
| if (error) |
| goto error0; |
| } |
| #endif |
| |
| if (ptr < numrecs) { |
| xfs_btree_shift_keys(cur, lkp, -1, numrecs - ptr); |
| xfs_btree_shift_ptrs(cur, lpp, -1, numrecs - ptr); |
| xfs_btree_log_keys(cur, bp, ptr, numrecs - 1); |
| xfs_btree_log_ptrs(cur, bp, ptr, numrecs - 1); |
| } |
| } else { |
| /* It's a leaf. operate on records */ |
| if (ptr < numrecs) { |
| xfs_btree_shift_recs(cur, |
| xfs_btree_rec_addr(cur, ptr + 1, block), |
| -1, numrecs - ptr); |
| xfs_btree_log_recs(cur, bp, ptr, numrecs - 1); |
| } |
| } |
| |
| /* |
| * Decrement and log the number of entries in the block. |
| */ |
| xfs_btree_set_numrecs(block, --numrecs); |
| xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS); |
| |
| /* |
| * If we are tracking the last record in the tree and |
| * we are at the far right edge of the tree, update it. |
| */ |
| if (xfs_btree_is_lastrec(cur, block, level)) { |
| cur->bc_ops->update_lastrec(cur, block, NULL, |
| ptr, LASTREC_DELREC); |
| } |
| |
| /* |
| * We're at the root level. First, shrink the root block in-memory. |
| * Try to get rid of the next level down. If we can't then there's |
| * nothing left to do. |
| */ |
| if (level == cur->bc_nlevels - 1) { |
| if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) { |
| xfs_iroot_realloc(cur->bc_private.b.ip, -1, |
| cur->bc_private.b.whichfork); |
| |
| error = xfs_btree_kill_iroot(cur); |
| if (error) |
| goto error0; |
| |
| error = xfs_btree_dec_cursor(cur, level, stat); |
| if (error) |
| goto error0; |
| *stat = 1; |
| return 0; |
| } |
| |
| /* |
| * 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) { |
| union xfs_btree_ptr *pp; |
| /* |
| * pp is still set to the first pointer in the block. |
| * Make it the new root of the btree. |
| */ |
| pp = xfs_btree_ptr_addr(cur, 1, block); |
| error = xfs_btree_kill_root(cur, bp, level, pp); |
| if (error) |
| goto error0; |
| } else if (level > 0) { |
| error = xfs_btree_dec_cursor(cur, level, stat); |
| if (error) |
| goto error0; |
| } |
| *stat = 1; |
| return 0; |
| } |
| |
| /* |
| * If we deleted the leftmost entry in the block, update the |
| * key values above us in the tree. |
| */ |
| if (xfs_btree_needs_key_update(cur, ptr)) { |
| error = xfs_btree_update_keys(cur, level); |
| if (error) |
| goto error0; |
| } |
| |
| /* |
| * If the number of records remaining in the block is at least |
| * the minimum, we're done. |
| */ |
| if (numrecs >= cur->bc_ops->get_minrecs(cur, level)) { |
| error = xfs_btree_dec_cursor(cur, level, stat); |
| if (error) |
| goto error0; |
| 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. |
| */ |
| xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB); |
| xfs_btree_get_sibling(cur, block, &lptr, XFS_BB_LEFTSIB); |
| |
| if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) { |
| /* |
| * One child of root, need to get a chance to copy its contents |
| * into the root and delete it. Can't go up to next level, |
| * there's nothing to delete there. |
| */ |
| if (xfs_btree_ptr_is_null(cur, &rptr) && |
| xfs_btree_ptr_is_null(cur, &lptr) && |
| level == cur->bc_nlevels - 2) { |
| error = xfs_btree_kill_iroot(cur); |
| if (!error) |
| error = xfs_btree_dec_cursor(cur, level, stat); |
| if (error) |
| goto error0; |
| return 0; |
| } |
| } |
| |
| ASSERT(!xfs_btree_ptr_is_null(cur, &rptr) || |
| !xfs_btree_ptr_is_null(cur, &lptr)); |
| |
| /* |
| * Duplicate the cursor so our btree manipulations here won't |
| * disrupt the next level up. |
| */ |
| error = xfs_btree_dup_cursor(cur, &tcur); |
| if (error) |
| goto error0; |
| |
| /* |
| * If there's a right sibling, see if it's ok to shift an entry |
| * out of it. |
| */ |
| if (!xfs_btree_ptr_is_null(cur, &rptr)) { |
| /* |
| * 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(cur->bc_mp, i == 1, error0); |
| |
| error = xfs_btree_increment(tcur, level, &i); |
| if (error) |
| goto error0; |
| XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0); |
| |
| i = xfs_btree_lastrec(tcur, level); |
| XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0); |
| |
| /* Grab a pointer to the block. */ |
| right = xfs_btree_get_block(tcur, level, &rbp); |
| #ifdef DEBUG |
| error = xfs_btree_check_block(tcur, right, level, rbp); |
| if (error) |
| goto error0; |
| #endif |
| /* Grab the current block number, for future use. */ |
| xfs_btree_get_sibling(tcur, right, &cptr, XFS_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 (xfs_btree_get_numrecs(right) - 1 >= |
| cur->bc_ops->get_minrecs(tcur, level)) { |
| error = xfs_btree_lshift(tcur, level, &i); |
| if (error) |
| goto error0; |
| if (i) { |
| ASSERT(xfs_btree_get_numrecs(block) >= |
| cur->bc_ops->get_minrecs(tcur, level)); |
| |
| xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); |
| tcur = NULL; |
| |
| error = xfs_btree_dec_cursor(cur, level, stat); |
| if (error) |
| goto error0; |
| 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 = xfs_btree_get_numrecs(right); |
| if (!xfs_btree_ptr_is_null(cur, &lptr)) { |
| i = xfs_btree_firstrec(tcur, level); |
| XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0); |
| |
| error = xfs_btree_decrement(tcur, level, &i); |
| if (error) |
| goto error0; |
| XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0); |
| } |
| } |
| |
| /* |
| * If there's a left sibling, see if it's ok to shift an entry |
| * out of it. |
| */ |
| if (!xfs_btree_ptr_is_null(cur, &lptr)) { |
| /* |
| * Move the temp cursor to the first entry in the |
| * previous block. |
| */ |
| i = xfs_btree_firstrec(tcur, level); |
| XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0); |
| |
| error = xfs_btree_decrement(tcur, level, &i); |
| if (error) |
| goto error0; |
| i = xfs_btree_firstrec(tcur, level); |
| XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0); |
| |
| /* Grab a pointer to the block. */ |
| left = xfs_btree_get_block(tcur, level, &lbp); |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, left, level, lbp); |
| if (error) |
| goto error0; |
| #endif |
| /* Grab the current block number, for future use. */ |
| xfs_btree_get_sibling(tcur, left, &cptr, XFS_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 (xfs_btree_get_numrecs(left) - 1 >= |
| cur->bc_ops->get_minrecs(tcur, level)) { |
| error = xfs_btree_rshift(tcur, level, &i); |
| if (error) |
| goto error0; |
| if (i) { |
| ASSERT(xfs_btree_get_numrecs(block) >= |
| cur->bc_ops->get_minrecs(tcur, level)); |
| xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); |
| tcur = NULL; |
| if (level == 0) |
| cur->bc_ptrs[0]++; |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = 1; |
| return 0; |
| } |
| } |
| |
| /* |
| * Otherwise, grab the number of records in right for |
| * future reference. |
| */ |
| lrecs = xfs_btree_get_numrecs(left); |
| } |
| |
| /* Delete the temp cursor, we're done with it. */ |
| xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); |
| tcur = NULL; |
| |
| /* If here, we need to do a join to keep the tree balanced. */ |
| ASSERT(!xfs_btree_ptr_is_null(cur, &cptr)); |
| |
| if (!xfs_btree_ptr_is_null(cur, &lptr) && |
| lrecs + xfs_btree_get_numrecs(block) <= |
| cur->bc_ops->get_maxrecs(cur, level)) { |
| /* |
| * Set "right" to be the starting block, |
| * "left" to be the left neighbor. |
| */ |
| rptr = cptr; |
| right = block; |
| rbp = bp; |
| error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp); |
| if (error) |
| goto error0; |
| |
| /* |
| * If that won't work, see if we can join with the right neighbor block. |
| */ |
| } else if (!xfs_btree_ptr_is_null(cur, &rptr) && |
| rrecs + xfs_btree_get_numrecs(block) <= |
| cur->bc_ops->get_maxrecs(cur, level)) { |
| /* |
| * Set "left" to be the starting block, |
| * "right" to be the right neighbor. |
| */ |
| lptr = cptr; |
| left = block; |
| lbp = bp; |
| error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp); |
| if (error) |
| goto error0; |
| |
| /* |
| * Otherwise, we can't fix the imbalance. |
| * Just return. This is probably a logic error, but it's not fatal. |
| */ |
| } else { |
| error = xfs_btree_dec_cursor(cur, level, stat); |
| if (error) |
| goto error0; |
| return 0; |
| } |
| |
| rrecs = xfs_btree_get_numrecs(right); |
| lrecs = xfs_btree_get_numrecs(left); |
| |
| /* |
| * We're now going to join "left" and "right" by moving all the stuff |
| * in "right" to "left" and deleting "right". |
| */ |
| XFS_BTREE_STATS_ADD(cur, moves, rrecs); |
| if (level > 0) { |
| /* It's a non-leaf. Move keys and pointers. */ |
| union xfs_btree_key *lkp; /* left btree key */ |
| union xfs_btree_ptr *lpp; /* left address pointer */ |
| union xfs_btree_key *rkp; /* right btree key */ |
| union xfs_btree_ptr *rpp; /* right address pointer */ |
| |
| lkp = xfs_btree_key_addr(cur, lrecs + 1, left); |
| lpp = xfs_btree_ptr_addr(cur, lrecs + 1, left); |
| rkp = xfs_btree_key_addr(cur, 1, right); |
| rpp = xfs_btree_ptr_addr(cur, 1, right); |
| #ifdef DEBUG |
| for (i = 1; i < rrecs; i++) { |
| error = xfs_btree_check_ptr(cur, rpp, i, level); |
| if (error) |
| goto error0; |
| } |
| #endif |
| xfs_btree_copy_keys(cur, lkp, rkp, rrecs); |
| xfs_btree_copy_ptrs(cur, lpp, rpp, rrecs); |
| |
| xfs_btree_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs); |
| xfs_btree_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs); |
| } else { |
| /* It's a leaf. Move records. */ |
| union xfs_btree_rec *lrp; /* left record pointer */ |
| union xfs_btree_rec *rrp; /* right record pointer */ |
| |
| lrp = xfs_btree_rec_addr(cur, lrecs + 1, left); |
| rrp = xfs_btree_rec_addr(cur, 1, right); |
| |
| xfs_btree_copy_recs(cur, lrp, rrp, rrecs); |
| xfs_btree_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs); |
| } |
| |
| XFS_BTREE_STATS_INC(cur, join); |
| |
| /* |
| * Fix up the number of records and right block pointer in the |
| * surviving block, and log it. |
| */ |
| xfs_btree_set_numrecs(left, lrecs + rrecs); |
| xfs_btree_get_sibling(cur, right, &cptr, XFS_BB_RIGHTSIB), |
| xfs_btree_set_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB); |
| xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB); |
| |
| /* If there is a right sibling, point it to the remaining block. */ |
| xfs_btree_get_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB); |
| if (!xfs_btree_ptr_is_null(cur, &cptr)) { |
| error = xfs_btree_read_buf_block(cur, &cptr, 0, &rrblock, &rrbp); |
| if (error) |
| goto error0; |
| xfs_btree_set_sibling(cur, rrblock, &lptr, XFS_BB_LEFTSIB); |
| xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB); |
| } |
| |
| /* Free the deleted block. */ |
| error = xfs_btree_free_block(cur, rbp); |
| if (error) |
| goto error0; |
| |
| /* |
| * 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) { |
| cur->bc_bufs[level] = lbp; |
| cur->bc_ptrs[level] += lrecs; |
| cur->bc_ra[level] = 0; |
| } |
| /* |
| * If we joined with the right neighbor and there's a level above |
| * us, increment the cursor at that level. |
| */ |
| else if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) || |
| (level + 1 < cur->bc_nlevels)) { |
| error = xfs_btree_increment(cur, level + 1, &i); |
| if (error) |
| goto error0; |
| } |
| |
| /* |
| * Readjust the ptr at this level if it's not a leaf, since it's |
| * still pointing at the deletion point, which makes the cursor |
| * inconsistent. If this makes the ptr 0, the caller fixes it up. |
| * We can't use decrement because it would change the next level up. |
| */ |
| if (level > 0) |
| cur->bc_ptrs[level]--; |
| |
| /* |
| * We combined blocks, so we have to update the parent keys if the |
| * btree supports overlapped intervals. However, bc_ptrs[level + 1] |
| * points to the old block so that the caller knows which record to |
| * delete. Therefore, the caller must be savvy enough to call updkeys |
| * for us if we return stat == 2. The other exit points from this |
| * function don't require deletions further up the tree, so they can |
| * call updkeys directly. |
| */ |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| /* Return value means the next level up has something to do. */ |
| *stat = 2; |
| return 0; |
| |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| if (tcur) |
| xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR); |
| return error; |
| } |
| |
| /* |
| * 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_btree_delete( |
| struct xfs_btree_cur *cur, |
| int *stat) /* success/failure */ |
| { |
| int error; /* error return value */ |
| int level; |
| int i; |
| bool joined = false; |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| |
| /* |
| * 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++) { |
| error = xfs_btree_delrec(cur, level, &i); |
| if (error) |
| goto error0; |
| if (i == 2) |
| joined = true; |
| } |
| |
| /* |
| * If we combined blocks as part of deleting the record, delrec won't |
| * have updated the parent high keys so we have to do that here. |
| */ |
| if (joined && (cur->bc_flags & XFS_BTREE_OVERLAPPING)) { |
| error = xfs_btree_updkeys_force(cur, 0); |
| if (error) |
| goto error0; |
| } |
| |
| if (i == 0) { |
| for (level = 1; level < cur->bc_nlevels; level++) { |
| if (cur->bc_ptrs[level] == 0) { |
| error = xfs_btree_decrement(cur, level, &i); |
| if (error) |
| goto error0; |
| break; |
| } |
| } |
| } |
| |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| *stat = i; |
| return 0; |
| error0: |
| XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| return error; |
| } |
| |
| /* |
| * Get the data from the pointed-to record. |
| */ |
| int /* error */ |
| xfs_btree_get_rec( |
| struct xfs_btree_cur *cur, /* btree cursor */ |
| union xfs_btree_rec **recp, /* output: btree record */ |
| int *stat) /* output: success/failure */ |
| { |
| struct xfs_btree_block *block; /* btree block */ |
| struct xfs_buf *bp; /* buffer pointer */ |
| int ptr; /* record number */ |
| #ifdef DEBUG |
| int error; /* error return value */ |
| #endif |
| |
| ptr = cur->bc_ptrs[0]; |
| block = xfs_btree_get_block(cur, 0, &bp); |
| |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, 0, bp); |
| if (error) |
| return error; |
| #endif |
| |
| /* |
| * Off the right end or left end, return failure. |
| */ |
| if (ptr > xfs_btree_get_numrecs(block) || ptr <= 0) { |
| *stat = 0; |
| return 0; |
| } |
| |
| /* |
| * Point to the record and extract its data. |
| */ |
| *recp = xfs_btree_rec_addr(cur, ptr, block); |
| *stat = 1; |
| return 0; |
| } |
| |
| /* Visit a block in a btree. */ |
| STATIC int |
| xfs_btree_visit_block( |
| struct xfs_btree_cur *cur, |
| int level, |
| xfs_btree_visit_blocks_fn fn, |
| void *data) |
| { |
| struct xfs_btree_block *block; |
| struct xfs_buf *bp; |
| union xfs_btree_ptr rptr; |
| int error; |
| |
| /* do right sibling readahead */ |
| xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA); |
| block = xfs_btree_get_block(cur, level, &bp); |
| |
| /* process the block */ |
| error = fn(cur, level, data); |
| if (error) |
| return error; |
| |
| /* now read rh sibling block for next iteration */ |
| xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB); |
| if (xfs_btree_ptr_is_null(cur, &rptr)) |
| return -ENOENT; |
| |
| return xfs_btree_lookup_get_block(cur, level, &rptr, &block); |
| } |
| |
| |
| /* Visit every block in a btree. */ |
| int |
| xfs_btree_visit_blocks( |
| struct xfs_btree_cur *cur, |
| xfs_btree_visit_blocks_fn fn, |
| void *data) |
| { |
| union xfs_btree_ptr lptr; |
| int level; |
| struct xfs_btree_block *block = NULL; |
| int error = 0; |
| |
| cur->bc_ops->init_ptr_from_cur(cur, &lptr); |
| |
| /* for each level */ |
| for (level = cur->bc_nlevels - 1; level >= 0; level--) { |
| /* grab the left hand block */ |
| error = xfs_btree_lookup_get_block(cur, level, &lptr, &block); |
| if (error) |
| return error; |
| |
| /* readahead the left most block for the next level down */ |
| if (level > 0) { |
| union xfs_btree_ptr *ptr; |
| |
| ptr = xfs_btree_ptr_addr(cur, 1, block); |
| xfs_btree_readahead_ptr(cur, ptr, 1); |
| |
| /* save for the next iteration of the loop */ |
| lptr = *ptr; |
| } |
| |
| /* for each buffer in the level */ |
| do { |
| error = xfs_btree_visit_block(cur, level, fn, data); |
| } while (!error); |
| |
| if (error != -ENOENT) |
| return error; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Change the owner of a btree. |
| * |
| * The mechanism we use here is ordered buffer logging. Because we don't know |
| * how many buffers were are going to need to modify, we don't really want to |
| * have to make transaction reservations for the worst case of every buffer in a |
| * full size btree as that may be more space that we can fit in the log.... |
| * |
| * We do the btree walk in the most optimal manner possible - we have sibling |
| * pointers so we can just walk all the blocks on each level from left to right |
| * in a single pass, and then move to the next level and do the same. We can |
| * also do readahead on the sibling pointers to get IO moving more quickly, |
| * though for slow disks this is unlikely to make much difference to performance |
| * as the amount of CPU work we have to do before moving to the next block is |
| * relatively small. |
| * |
| * For each btree block that we load, modify the owner appropriately, set the |
| * buffer as an ordered buffer and log it appropriately. We need to ensure that |
| * we mark the region we change dirty so that if the buffer is relogged in |
| * a subsequent transaction the changes we make here as an ordered buffer are |
| * correctly relogged in that transaction. If we are in recovery context, then |
| * just queue the modified buffer as delayed write buffer so the transaction |
| * recovery completion writes the changes to disk. |
| */ |
| struct xfs_btree_block_change_owner_info { |
| __uint64_t new_owner; |
| struct list_head *buffer_list; |
| }; |
| |
| static int |
| xfs_btree_block_change_owner( |
| struct xfs_btree_cur *cur, |
| int level, |
| void *data) |
| { |
| struct xfs_btree_block_change_owner_info *bbcoi = data; |
| struct xfs_btree_block *block; |
| struct xfs_buf *bp; |
| |
| /* modify the owner */ |
| block = xfs_btree_get_block(cur, level, &bp); |
| if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| block->bb_u.l.bb_owner = cpu_to_be64(bbcoi->new_owner); |
| else |
| block->bb_u.s.bb_owner = cpu_to_be32(bbcoi->new_owner); |
| |
| /* |
| * If the block is a root block hosted in an inode, we might not have a |
| * buffer pointer here and we shouldn't attempt to log the change as the |
| * information is already held in the inode and discarded when the root |
| * block is formatted into the on-disk inode fork. We still change it, |
| * though, so everything is consistent in memory. |
| */ |
| if (bp) { |
| if (cur->bc_tp) { |
| xfs_trans_ordered_buf(cur->bc_tp, bp); |
| xfs_btree_log_block(cur, bp, XFS_BB_OWNER); |
| } else { |
| xfs_buf_delwri_queue(bp, bbcoi->buffer_list); |
| } |
| } else { |
| ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE); |
| ASSERT(level == cur->bc_nlevels - 1); |
| } |
| |
| return 0; |
| } |
| |
| int |
| xfs_btree_change_owner( |
| struct xfs_btree_cur *cur, |
| __uint64_t new_owner, |
| struct list_head *buffer_list) |
| { |
| struct xfs_btree_block_change_owner_info bbcoi; |
| |
| bbcoi.new_owner = new_owner; |
| bbcoi.buffer_list = buffer_list; |
| |
| return xfs_btree_visit_blocks(cur, xfs_btree_block_change_owner, |
| &bbcoi); |
| } |
| |
| /** |
| * xfs_btree_sblock_v5hdr_verify() -- verify the v5 fields of a short-format |
| * btree block |
| * |
| * @bp: buffer containing the btree block |
| * @max_recs: pointer to the m_*_mxr max records field in the xfs mount |
| * @pag_max_level: pointer to the per-ag max level field |
| */ |
| bool |
| xfs_btree_sblock_v5hdr_verify( |
| struct xfs_buf *bp) |
| { |
| struct xfs_mount *mp = bp->b_target->bt_mount; |
| struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp); |
| struct xfs_perag *pag = bp->b_pag; |
| |
| if (!xfs_sb_version_hascrc(&mp->m_sb)) |
| return false; |
| if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid)) |
| return false; |
| if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn)) |
| return false; |
| if (pag && be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno) |
| return false; |
| return true; |
| } |
| |
| /** |
| * xfs_btree_sblock_verify() -- verify a short-format btree block |
| * |
| * @bp: buffer containing the btree block |
| * @max_recs: maximum records allowed in this btree node |
| */ |
| bool |
| xfs_btree_sblock_verify( |
| struct xfs_buf *bp, |
| unsigned int max_recs) |
| { |
| struct xfs_mount *mp = bp->b_target->bt_mount; |
| struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp); |
| |
| /* numrecs verification */ |
| if (be16_to_cpu(block->bb_numrecs) > max_recs) |
| return false; |
| |
| /* sibling pointer verification */ |
| if (!block->bb_u.s.bb_leftsib || |
| (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks && |
| block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK))) |
| return false; |
| if (!block->bb_u.s.bb_rightsib || |
| (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks && |
| block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK))) |
| return false; |
| |
| return true; |
| } |
| |
| /* |
| * Calculate the number of btree levels needed to store a given number of |
| * records in a short-format btree. |
| */ |
| uint |
| xfs_btree_compute_maxlevels( |
| struct xfs_mount *mp, |
| uint *limits, |
| unsigned long len) |
| { |
| uint level; |
| unsigned long maxblocks; |
| |
| maxblocks = (len + limits[0] - 1) / limits[0]; |
| for (level = 1; maxblocks > 1; level++) |
| maxblocks = (maxblocks + limits[1] - 1) / limits[1]; |
| return level; |
| } |
| |
| /* |
| * Query a regular btree for all records overlapping a given interval. |
| * Start with a LE lookup of the key of low_rec and return all records |
| * until we find a record with a key greater than the key of high_rec. |
| */ |
| STATIC int |
| xfs_btree_simple_query_range( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_key *low_key, |
| union xfs_btree_key *high_key, |
| xfs_btree_query_range_fn fn, |
| void *priv) |
| { |
| union xfs_btree_rec *recp; |
| union xfs_btree_key rec_key; |
| __int64_t diff; |
| int stat; |
| bool firstrec = true; |
| int error; |
| |
| ASSERT(cur->bc_ops->init_high_key_from_rec); |
| ASSERT(cur->bc_ops->diff_two_keys); |
| |
| /* |
| * Find the leftmost record. The btree cursor must be set |
| * to the low record used to generate low_key. |
| */ |
| stat = 0; |
| error = xfs_btree_lookup(cur, XFS_LOOKUP_LE, &stat); |
| if (error) |
| goto out; |
| |
| /* Nothing? See if there's anything to the right. */ |
| if (!stat) { |
| error = xfs_btree_increment(cur, 0, &stat); |
| if (error) |
| goto out; |
| } |
| |
| while (stat) { |
| /* Find the record. */ |
| error = xfs_btree_get_rec(cur, &recp, &stat); |
| if (error || !stat) |
| break; |
| |
| /* Skip if high_key(rec) < low_key. */ |
| if (firstrec) { |
| cur->bc_ops->init_high_key_from_rec(&rec_key, recp); |
| firstrec = false; |
| diff = cur->bc_ops->diff_two_keys(cur, low_key, |
| &rec_key); |
| if (diff > 0) |
| goto advloop; |
| } |
| |
| /* Stop if high_key < low_key(rec). */ |
| cur->bc_ops->init_key_from_rec(&rec_key, recp); |
| diff = cur->bc_ops->diff_two_keys(cur, &rec_key, high_key); |
| if (diff > 0) |
| break; |
| |
| /* Callback */ |
| error = fn(cur, recp, priv); |
| if (error < 0 || error == XFS_BTREE_QUERY_RANGE_ABORT) |
| break; |
| |
| advloop: |
| /* Move on to the next record. */ |
| error = xfs_btree_increment(cur, 0, &stat); |
| if (error) |
| break; |
| } |
| |
| out: |
| return error; |
| } |
| |
| /* |
| * Query an overlapped interval btree for all records overlapping a given |
| * interval. This function roughly follows the algorithm given in |
| * "Interval Trees" of _Introduction to Algorithms_, which is section |
| * 14.3 in the 2nd and 3rd editions. |
| * |
| * First, generate keys for the low and high records passed in. |
| * |
| * For any leaf node, generate the high and low keys for the record. |
| * If the record keys overlap with the query low/high keys, pass the |
| * record to the function iterator. |
| * |
| * For any internal node, compare the low and high keys of each |
| * pointer against the query low/high keys. If there's an overlap, |
| * follow the pointer. |
| * |
| * As an optimization, we stop scanning a block when we find a low key |
| * that is greater than the query's high key. |
| */ |
| STATIC int |
| xfs_btree_overlapped_query_range( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_key *low_key, |
| union xfs_btree_key *high_key, |
| xfs_btree_query_range_fn fn, |
| void *priv) |
| { |
| union xfs_btree_ptr ptr; |
| union xfs_btree_ptr *pp; |
| union xfs_btree_key rec_key; |
| union xfs_btree_key rec_hkey; |
| union xfs_btree_key *lkp; |
| union xfs_btree_key *hkp; |
| union xfs_btree_rec *recp; |
| struct xfs_btree_block *block; |
| __int64_t ldiff; |
| __int64_t hdiff; |
| int level; |
| struct xfs_buf *bp; |
| int i; |
| int error; |
| |
| /* Load the root of the btree. */ |
| level = cur->bc_nlevels - 1; |
| cur->bc_ops->init_ptr_from_cur(cur, &ptr); |
| error = xfs_btree_lookup_get_block(cur, level, &ptr, &block); |
| if (error) |
| return error; |
| xfs_btree_get_block(cur, level, &bp); |
| trace_xfs_btree_overlapped_query_range(cur, level, bp); |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, level, bp); |
| if (error) |
| goto out; |
| #endif |
| cur->bc_ptrs[level] = 1; |
| |
| while (level < cur->bc_nlevels) { |
| block = xfs_btree_get_block(cur, level, &bp); |
| |
| /* End of node, pop back towards the root. */ |
| if (cur->bc_ptrs[level] > be16_to_cpu(block->bb_numrecs)) { |
| pop_up: |
| if (level < cur->bc_nlevels - 1) |
| cur->bc_ptrs[level + 1]++; |
| level++; |
| continue; |
| } |
| |
| if (level == 0) { |
| /* Handle a leaf node. */ |
| recp = xfs_btree_rec_addr(cur, cur->bc_ptrs[0], block); |
| |
| cur->bc_ops->init_high_key_from_rec(&rec_hkey, recp); |
| ldiff = cur->bc_ops->diff_two_keys(cur, &rec_hkey, |
| low_key); |
| |
| cur->bc_ops->init_key_from_rec(&rec_key, recp); |
| hdiff = cur->bc_ops->diff_two_keys(cur, high_key, |
| &rec_key); |
| |
| /* |
| * If (record's high key >= query's low key) and |
| * (query's high key >= record's low key), then |
| * this record overlaps the query range; callback. |
| */ |
| if (ldiff >= 0 && hdiff >= 0) { |
| error = fn(cur, recp, priv); |
| if (error < 0 || |
| error == XFS_BTREE_QUERY_RANGE_ABORT) |
| break; |
| } else if (hdiff < 0) { |
| /* Record is larger than high key; pop. */ |
| goto pop_up; |
| } |
| cur->bc_ptrs[level]++; |
| continue; |
| } |
| |
| /* Handle an internal node. */ |
| lkp = xfs_btree_key_addr(cur, cur->bc_ptrs[level], block); |
| hkp = xfs_btree_high_key_addr(cur, cur->bc_ptrs[level], block); |
| pp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[level], block); |
| |
| ldiff = cur->bc_ops->diff_two_keys(cur, hkp, low_key); |
| hdiff = cur->bc_ops->diff_two_keys(cur, high_key, lkp); |
| |
| /* |
| * If (pointer's high key >= query's low key) and |
| * (query's high key >= pointer's low key), then |
| * this record overlaps the query range; follow pointer. |
| */ |
| if (ldiff >= 0 && hdiff >= 0) { |
| level--; |
| error = xfs_btree_lookup_get_block(cur, level, pp, |
| &block); |
| if (error) |
| goto out; |
| xfs_btree_get_block(cur, level, &bp); |
| trace_xfs_btree_overlapped_query_range(cur, level, bp); |
| #ifdef DEBUG |
| error = xfs_btree_check_block(cur, block, level, bp); |
| if (error) |
| goto out; |
| #endif |
| cur->bc_ptrs[level] = 1; |
| continue; |
| } else if (hdiff < 0) { |
| /* The low key is larger than the upper range; pop. */ |
| goto pop_up; |
| } |
| cur->bc_ptrs[level]++; |
| } |
| |
| out: |
| /* |
| * If we don't end this function with the cursor pointing at a record |
| * block, a subsequent non-error cursor deletion will not release |
| * node-level buffers, causing a buffer leak. This is quite possible |
| * with a zero-results range query, so release the buffers if we |
| * failed to return any results. |
| */ |
| if (cur->bc_bufs[0] == NULL) { |
| for (i = 0; i < cur->bc_nlevels; i++) { |
| if (cur->bc_bufs[i]) { |
| xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]); |
| cur->bc_bufs[i] = NULL; |
| cur->bc_ptrs[i] = 0; |
| cur->bc_ra[i] = 0; |
| } |
| } |
| } |
| |
| return error; |
| } |
| |
| /* |
| * Query a btree for all records overlapping a given interval of keys. The |
| * supplied function will be called with each record found; return one of the |
| * XFS_BTREE_QUERY_RANGE_{CONTINUE,ABORT} values or the usual negative error |
| * code. This function returns XFS_BTREE_QUERY_RANGE_ABORT, zero, or a |
| * negative error code. |
| */ |
| int |
| xfs_btree_query_range( |
| struct xfs_btree_cur *cur, |
| union xfs_btree_irec *low_rec, |
| union xfs_btree_irec *high_rec, |
| xfs_btree_query_range_fn fn, |
| void *priv) |
| { |
| union xfs_btree_rec rec; |
| union xfs_btree_key low_key; |
| union xfs_btree_key high_key; |
| |
| /* Find the keys of both ends of the interval. */ |
| cur->bc_rec = *high_rec; |
| cur->bc_ops->init_rec_from_cur(cur, &rec); |
| cur->bc_ops->init_key_from_rec(&high_key, &rec); |
| |
| cur->bc_rec = *low_rec; |
| cur->bc_ops->init_rec_from_cur(cur, &rec); |
| cur->bc_ops->init_key_from_rec(&low_key, &rec); |
| |
| /* Enforce low key < high key. */ |
| if (cur->bc_ops->diff_two_keys(cur, &low_key, &high_key) > 0) |
| return -EINVAL; |
| |
| if (!(cur->bc_flags & XFS_BTREE_OVERLAPPING)) |
| return xfs_btree_simple_query_range(cur, &low_key, |
| &high_key, fn, priv); |
| return xfs_btree_overlapped_query_range(cur, &low_key, &high_key, |
| fn, priv); |
| } |
| |
| /* |
| * Calculate the number of blocks needed to store a given number of records |
| * in a short-format (per-AG metadata) btree. |
| */ |
| xfs_extlen_t |
| xfs_btree_calc_size( |
| struct xfs_mount *mp, |
| uint *limits, |
| unsigned long long len) |
| { |
| int level; |
| int maxrecs; |
| xfs_extlen_t rval; |
| |
| maxrecs = limits[0]; |
| for (level = 0, rval = 0; len > 1; level++) { |
| len += maxrecs - 1; |
| do_div(len, maxrecs); |
| maxrecs = limits[1]; |
| rval += len; |
| } |
| return rval; |
| } |
| |
| static int |
| xfs_btree_count_blocks_helper( |
| struct xfs_btree_cur *cur, |
| int level, |
| void *data) |
| { |
| xfs_extlen_t *blocks = data; |
| (*blocks)++; |
| |
| return 0; |
| } |
| |
| /* Count the blocks in a btree and return the result in *blocks. */ |
| int |
| xfs_btree_count_blocks( |
| struct xfs_btree_cur *cur, |
| xfs_extlen_t *blocks) |
| { |
| *blocks = 0; |
| return xfs_btree_visit_blocks(cur, xfs_btree_count_blocks_helper, |
| blocks); |
| } |