diff options
Diffstat (limited to 'fs/xfs/libxfs/xfs_btree.c')
| -rw-r--r-- | fs/xfs/libxfs/xfs_btree.c | 914 |
1 files changed, 764 insertions, 150 deletions
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c index 07eeb0b4ca74..b5c213a051cd 100644 --- a/fs/xfs/libxfs/xfs_btree.c +++ b/fs/xfs/libxfs/xfs_btree.c @@ -23,6 +23,7 @@ #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" @@ -43,15 +44,14 @@ 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, XFS_BMAP_MAGIC, XFS_IBT_MAGIC, + { XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, 0, XFS_BMAP_MAGIC, XFS_IBT_MAGIC, XFS_FIBT_MAGIC }, - { XFS_ABTB_CRC_MAGIC, XFS_ABTC_CRC_MAGIC, + { XFS_ABTB_CRC_MAGIC, XFS_ABTC_CRC_MAGIC, XFS_RMAP_CRC_MAGIC, XFS_BMAP_CRC_MAGIC, XFS_IBT_CRC_MAGIC, XFS_FIBT_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 */ @@ -428,6 +428,50 @@ xfs_btree_dup_cursor( * 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. */ /* @@ -479,6 +523,18 @@ xfs_btree_key_offset( } /* + * 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 @@ -519,6 +575,19 @@ xfs_btree_key_addr( } /* + * 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 * @@ -1144,6 +1213,9 @@ xfs_btree_set_refs( 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; default: ASSERT(0); } @@ -1879,32 +1951,214 @@ error0: 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); +} + /* - * Update keys at all levels from here to the root along the cursor's path. + * 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_updkey( +__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_bigkey 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 = (union xfs_btree_key *)&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, - union xfs_btree_key *keyp, 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); - ASSERT(!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) || level >= 1); - /* * Go up the tree from this level toward the root. * At each level, update the key value to the value input. * Stop when we reach a level where the cursor isn't pointing * at the first entry in the block. */ - for (ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) { + xfs_btree_get_keys(cur, block, &key); + for (level++, ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) { #ifdef DEBUG int error; #endif @@ -1918,7 +2172,7 @@ xfs_btree_updkey( #endif ptr = cur->bc_ptrs[level]; kp = xfs_btree_key_addr(cur, ptr, block); - xfs_btree_copy_keys(cur, kp, keyp, 1); + xfs_btree_copy_keys(cur, kp, &key, 1); xfs_btree_log_keys(cur, bp, ptr, ptr); } @@ -1970,12 +2224,9 @@ xfs_btree_update( ptr, LASTREC_UPDATE); } - /* Updating first rec in leaf. Pass new key value up to our parent. */ - if (ptr == 1) { - union xfs_btree_key key; - - cur->bc_ops->init_key_from_rec(&key, rec); - error = xfs_btree_updkey(cur, &key, 1); + /* 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; } @@ -1998,18 +2249,19 @@ xfs_btree_lshift( int level, int *stat) /* success/failure */ { - union xfs_btree_key key; /* btree key */ struct xfs_buf *lbp; /* left buffer pointer */ struct xfs_btree_block *left; /* left btree block */ int lrecs; /* left record count */ struct xfs_buf *rbp; /* right buffer pointer */ struct xfs_btree_block *right; /* right btree block */ + 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); @@ -2139,18 +2391,33 @@ xfs_btree_lshift( xfs_btree_rec_addr(cur, 2, right), -1, rrecs); xfs_btree_log_recs(cur, rbp, 1, rrecs); + } - /* - * If it's the first record in the block, we'll need a key - * structure to pass up to the next level (updkey). - */ - cur->bc_ops->init_key_from_rec(&key, - xfs_btree_rec_addr(cur, 1, right)); - rkp = &key; + /* + * 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 key values of right. */ - error = xfs_btree_updkey(cur, rkp, level + 1); + /* Update the parent keys of the right block. */ + error = xfs_btree_update_keys(cur, level); if (error) goto error0; @@ -2169,6 +2436,11 @@ out0: 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; } /* @@ -2181,7 +2453,6 @@ xfs_btree_rshift( int level, int *stat) /* success/failure */ { - union xfs_btree_key key; /* btree key */ struct xfs_buf *lbp; /* left buffer pointer */ struct xfs_btree_block *left; /* left btree block */ struct xfs_buf *rbp; /* right buffer pointer */ @@ -2290,12 +2561,6 @@ xfs_btree_rshift( /* Now put the new data in, and log it. */ xfs_btree_copy_recs(cur, rrp, lrp, 1); xfs_btree_log_recs(cur, rbp, 1, rrecs + 1); - - cur->bc_ops->init_key_from_rec(&key, rrp); - rkp = &key; - - ASSERT(cur->bc_ops->recs_inorder(cur, rrp, - xfs_btree_rec_addr(cur, 2, right))); } /* @@ -2315,13 +2580,21 @@ xfs_btree_rshift( if (error) goto error0; i = xfs_btree_lastrec(tcur, level); - XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0); + XFS_WANT_CORRUPTED_GOTO(tcur->bc_mp, i == 1, error0); error = xfs_btree_increment(tcur, level, &i); if (error) goto error1; - error = xfs_btree_updkey(tcur, rkp, level + 1); + /* 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; @@ -2422,6 +2695,11 @@ __xfs_btree_split( 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 @@ -2447,14 +2725,15 @@ __xfs_btree_split( } #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); - /* Grab the keys to the entries moved to the right block */ - xfs_btree_copy_keys(cur, key, rkp, 1); + /* 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 */ @@ -2463,27 +2742,23 @@ __xfs_btree_split( 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); - cur->bc_ops->init_key_from_rec(key, - xfs_btree_rec_addr(cur, 1, right)); + /* 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 numrecs, sibling pointers. + * 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); - lrecs -= rrecs; - xfs_btree_set_numrecs(left, lrecs); - xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs); - xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS); xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB); @@ -2499,6 +2774,14 @@ __xfs_btree_split( 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 @@ -2802,6 +3085,7 @@ xfs_btree_new_root( 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); @@ -2810,19 +3094,24 @@ xfs_btree_new_root( /* Fill in the key data in the new root. */ if (xfs_btree_get_level(left) > 0) { - xfs_btree_copy_keys(cur, - xfs_btree_key_addr(cur, 1, new), - xfs_btree_key_addr(cur, 1, left), 1); - xfs_btree_copy_keys(cur, - xfs_btree_key_addr(cur, 2, new), - xfs_btree_key_addr(cur, 1, right), 1); + /* + * 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 { - cur->bc_ops->init_key_from_rec( - xfs_btree_key_addr(cur, 1, new), - xfs_btree_rec_addr(cur, 1, left)); - cur->bc_ops->init_key_from_rec( - xfs_btree_key_addr(cur, 2, new), - xfs_btree_rec_addr(cur, 1, right)); + /* + * 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); @@ -2858,10 +3147,9 @@ xfs_btree_make_block_unfull( int *index, /* new tree index */ union xfs_btree_ptr *nptr, /* new btree ptr */ struct xfs_btree_cur **ncur, /* new btree cursor */ - union xfs_btree_rec *nrec, /* new record */ + union xfs_btree_key *key, /* key of new block */ int *stat) { - union xfs_btree_key key; /* new btree key value */ int error = 0; if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && @@ -2871,6 +3159,7 @@ xfs_btree_make_block_unfull( 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; @@ -2906,13 +3195,12 @@ xfs_btree_make_block_unfull( * 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); + error = xfs_btree_split(cur, level, nptr, key, ncur, stat); if (error || *stat == 0) return error; *index = cur->bc_ptrs[level]; - cur->bc_ops->init_rec_from_key(&key, nrec); return 0; } @@ -2925,16 +3213,17 @@ 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 *recp, /* i/o: record data 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_key key; /* btree key */ union xfs_btree_ptr nptr; /* new block ptr */ struct xfs_btree_cur *ncur; /* new btree cursor */ - union xfs_btree_rec nrec; /* new record count */ + union xfs_btree_bigkey 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 */ @@ -2942,11 +3231,13 @@ xfs_btree_insrec( #ifdef DEBUG int i; #endif + xfs_daddr_t old_bn; XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); - XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, recp); + XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, &rec); ncur = NULL; + lkey = (union xfs_btree_key *)&nkey; /* * If we have an external root pointer, and we've made it to the @@ -2969,15 +3260,13 @@ xfs_btree_insrec( return 0; } - /* Make a key out of the record data to be inserted, and save it. */ - cur->bc_ops->init_key_from_rec(&key, recp); - 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 @@ -2988,10 +3277,10 @@ xfs_btree_insrec( /* 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, recp, + ASSERT(cur->bc_ops->recs_inorder(cur, rec, xfs_btree_rec_addr(cur, ptr, block))); } else { - ASSERT(cur->bc_ops->keys_inorder(cur, &key, + ASSERT(cur->bc_ops->keys_inorder(cur, key, xfs_btree_key_addr(cur, ptr, block))); } } @@ -3004,7 +3293,7 @@ xfs_btree_insrec( 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, &nrec, stat); + &optr, &ptr, &nptr, &ncur, lkey, stat); if (error || *stat == 0) goto error0; } @@ -3054,7 +3343,7 @@ xfs_btree_insrec( #endif /* Now put the new data in, bump numrecs and log it. */ - xfs_btree_copy_keys(cur, kp, &key, 1); + xfs_btree_copy_keys(cur, kp, key, 1); xfs_btree_copy_ptrs(cur, pp, ptrp, 1); numrecs++; xfs_btree_set_numrecs(block, numrecs); @@ -3075,7 +3364,7 @@ xfs_btree_insrec( 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, recp, 1); + xfs_btree_copy_recs(cur, rp, rec, 1); xfs_btree_set_numrecs(block, ++numrecs); xfs_btree_log_recs(cur, bp, ptr, numrecs); #ifdef DEBUG @@ -3089,9 +3378,18 @@ xfs_btree_insrec( /* Log the new number of records in the btree header. */ xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS); - /* If we inserted at the start of a block, update the parents' keys. */ - if (optr == 1) { - error = xfs_btree_updkey(cur, &key, level + 1); + /* + * 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; } @@ -3101,7 +3399,7 @@ xfs_btree_insrec( * 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, recp, + cur->bc_ops->update_lastrec(cur, block, rec, ptr, LASTREC_INSREC); } @@ -3111,7 +3409,7 @@ xfs_btree_insrec( */ *ptrp = nptr; if (!xfs_btree_ptr_is_null(cur, &nptr)) { - *recp = nrec; + xfs_btree_copy_keys(cur, key, lkey, 1); *curp = ncur; } @@ -3142,14 +3440,20 @@ xfs_btree_insert( 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_bigkey 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 = (union xfs_btree_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. @@ -3161,7 +3465,8 @@ xfs_btree_insert( * 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, &ncur, &i); + error = xfs_btree_insrec(pcur, level, &nptr, &rec, key, + &ncur, &i); if (error) { if (pcur != cur) xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR); @@ -3385,8 +3690,6 @@ xfs_btree_delrec( struct xfs_buf *bp; /* buffer for block */ int error; /* error return value */ int i; /* loop counter */ - union xfs_btree_key key; /* storage for keyp */ - union xfs_btree_key *keyp = &key; /* passed to the next level */ union xfs_btree_ptr lptr; /* left sibling block ptr */ struct xfs_buf *lbp; /* left buffer pointer */ struct xfs_btree_block *left; /* left btree block */ @@ -3457,13 +3760,6 @@ xfs_btree_delrec( xfs_btree_log_keys(cur, bp, ptr, numrecs - 1); xfs_btree_log_ptrs(cur, bp, ptr, numrecs - 1); } - - /* - * If it's the first record in the block, we'll need to pass a - * key up to the next level (updkey). - */ - if (ptr == 1) - keyp = xfs_btree_key_addr(cur, 1, block); } else { /* It's a leaf. operate on records */ if (ptr < numrecs) { @@ -3472,16 +3768,6 @@ xfs_btree_delrec( -1, numrecs - ptr); xfs_btree_log_recs(cur, bp, ptr, numrecs - 1); } - - /* - * If it's the first record in the block, we'll need a key - * structure to pass up to the next level (updkey). - */ - if (ptr == 1) { - cur->bc_ops->init_key_from_rec(&key, - xfs_btree_rec_addr(cur, 1, block)); - keyp = &key; - } } /* @@ -3548,8 +3834,8 @@ xfs_btree_delrec( * If we deleted the leftmost entry in the block, update the * key values above us in the tree. */ - if (ptr == 1) { - error = xfs_btree_updkey(cur, keyp, level + 1); + if (xfs_btree_needs_key_update(cur, ptr)) { + error = xfs_btree_update_keys(cur, level); if (error) goto error0; } @@ -3878,6 +4164,16 @@ xfs_btree_delrec( 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; @@ -3903,6 +4199,7 @@ xfs_btree_delete( int error; /* error return value */ int level; int i; + bool joined = false; XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); @@ -3916,6 +4213,18 @@ xfs_btree_delete( 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) { @@ -3978,6 +4287,81 @@ xfs_btree_get_rec( 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. * @@ -4002,26 +4386,27 @@ xfs_btree_get_rec( * 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, - __uint64_t new_owner, - struct list_head *buffer_list) + void *data) { + struct xfs_btree_block_change_owner_info *bbcoi = data; struct xfs_btree_block *block; struct xfs_buf *bp; - union xfs_btree_ptr rptr; - - /* do right sibling readahead */ - xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA); /* 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(new_owner); + block->bb_u.l.bb_owner = cpu_to_be64(bbcoi->new_owner); else - block->bb_u.s.bb_owner = cpu_to_be32(new_owner); + 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 @@ -4035,19 +4420,14 @@ xfs_btree_block_change_owner( xfs_trans_ordered_buf(cur->bc_tp, bp); xfs_btree_log_block(cur, bp, XFS_BB_OWNER); } else { - xfs_buf_delwri_queue(bp, buffer_list); + xfs_buf_delwri_queue(bp, bbcoi->buffer_list); } } else { ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE); ASSERT(level == cur->bc_nlevels - 1); } - /* 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); + return 0; } int @@ -4056,43 +4436,13 @@ xfs_btree_change_owner( __uint64_t new_owner, struct list_head *buffer_list) { - 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_block_change_owner(cur, level, - new_owner, - buffer_list); - } while (!error); + struct xfs_btree_block_change_owner_info bbcoi; - if (error != -ENOENT) - return error; - } + bbcoi.new_owner = new_owner; + bbcoi.buffer_list = buffer_list; - return 0; + return xfs_btree_visit_blocks(cur, xfs_btree_block_change_owner, + &bbcoi); } /** @@ -4171,3 +4521,267 @@ xfs_btree_compute_maxlevels( 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; + + while (stat) { + /* Find the record. */ + error = xfs_btree_get_rec(cur, &recp, &stat); + if (error || !stat) + break; + cur->bc_ops->init_high_key_from_rec(&rec_key, recp); + + /* Skip if high_key(rec) < low_key. */ + if (firstrec) { + 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). */ + 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); +} |