/* * linux/fs/hfs/bfind.c * * Copyright (C) 2001 * Brad Boyer (flar@allandria.com) * (C) 2003 Ardis Technologies * * Search routines for btrees */ #include #include "btree.h" int hfs_find_init(struct hfs_btree *tree, struct hfs_find_data *fd) { void *ptr; fd->tree = tree; fd->bnode = NULL; ptr = kmalloc(tree->max_key_len * 2 + 4, GFP_KERNEL); if (!ptr) return -ENOMEM; fd->search_key = ptr; fd->key = ptr + tree->max_key_len + 2; hfs_dbg(BNODE_REFS, "find_init: %d (%p)\n", tree->cnid, __builtin_return_address(0)); mutex_lock(&tree->tree_lock); return 0; } void hfs_find_exit(struct hfs_find_data *fd) { hfs_bnode_put(fd->bnode); kfree(fd->search_key); hfs_dbg(BNODE_REFS, "find_exit: %d (%p)\n", fd->tree->cnid, __builtin_return_address(0)); mutex_unlock(&fd->tree->tree_lock); fd->tree = NULL; } /* Find the record in bnode that best matches key (not greater than...)*/ int __hfs_brec_find(struct hfs_bnode *bnode, struct hfs_find_data *fd) { int cmpval; u16 off, len, keylen; int rec; int b, e; int res; b = 0; e = bnode->num_recs - 1; res = -ENOENT; do { rec = (e + b) / 2; len = hfs_brec_lenoff(bnode, rec, &off); keylen = hfs_brec_keylen(bnode, rec); if (keylen == 0) { res = -EINVAL; goto fail; } hfs_bnode_read(bnode, fd->key, off, keylen); cmpval = bnode->tree->keycmp(fd->key, fd->search_key); if (!cmpval) { e = rec; res = 0; goto done; } if (cmpval < 0) b = rec + 1; else e = rec - 1; } while (b <= e); if (rec != e && e >= 0) { len = hfs_brec_lenoff(bnode, e, &off); keylen = hfs_brec_keylen(bnode, e); if (keylen == 0) { res = -EINVAL; goto fail; } hfs_bnode_read(bnode, fd->key, off, keylen); } done: fd->record = e; fd->keyoffset = off; fd->keylength = keylen; fd->entryoffset = off + keylen; fd->entrylength = len - keylen; fail: return res; } /* Traverse a B*Tree from the root to a leaf finding best fit to key */ /* Return allocated copy of node found, set recnum to best record */ int hfs_brec_find(struct hfs_find_data *fd) { struct hfs_btree *tree; struct hfs_bnode *bnode; u32 nidx, parent; __be32 data; int height, res; tree = fd->tree; if (fd->bnode) hfs_bnode_put(fd->bnode); fd->bnode = NULL; nidx = tree->root; if (!nidx) return -ENOENT; height = tree->depth; res = 0; parent = 0; for (;;) { bnode = hfs_bnode_find(tree, nidx); if (IS_ERR(bnode)) { res = PTR_ERR(bnode); bnode = NULL; break; } if (bnode->height != height) goto invalid; if (bnode->type != (--height ? HFS_NODE_INDEX : HFS_NODE_LEAF)) goto invalid; bnode->parent = parent; res = __hfs_brec_find(bnode, fd); if (!height) break; if (fd->record < 0) goto release; parent = nidx; hfs_bnode_read(bnode, &data, fd->entryoffset, 4); nidx = be32_to_cpu(data); hfs_bnode_put(bnode); } fd->bnode = bnode; return res; invalid: pr_err("inconsistency in B*Tree (%d,%d,%d,%u,%u)\n", height, bnode->height, bnode->type, nidx, parent); res = -EIO; release: hfs_bnode_put(bnode); return res; } int hfs_brec_read(struct hfs_find_data *fd, void *rec, int rec_len) { int res; res = hfs_brec_find(fd); if (res) return res; if (fd->entrylength > rec_len) return -EINVAL; hfs_bnode_read(fd->bnode, rec, fd->entryoffset, fd->entrylength); return 0; } int hfs_brec_goto(struct hfs_find_data *fd, int cnt) { struct hfs_btree *tree; struct hfs_bnode *bnode; int idx, res = 0; u16 off, len, keylen; bnode = fd->bnode; tree = bnode->tree; if (cnt < 0) { cnt = -cnt; while (cnt > fd->record) { cnt -= fd->record + 1; fd->record = bnode->num_recs - 1; idx = bnode->prev; if (!idx) { res = -ENOENT; goto out; } hfs_bnode_put(bnode); bnode = hfs_bnode_find(tree, idx); if (IS_ERR(bnode)) { res = PTR_ERR(bnode); bnode = NULL; goto out; } } fd->record -= cnt; } else { while (cnt >= bnode->num_recs - fd->record) { cnt -= bnode->num_recs - fd->record; fd->record = 0; idx = bnode->next; if (!idx) { res = -ENOENT; goto out; } hfs_bnode_put(bnode); bnode = hfs_bnode_find(tree, idx); if (IS_ERR(bnode)) { res = PTR_ERR(bnode); bnode = NULL; goto out; } } fd->record += cnt; } len = hfs_brec_lenoff(bnode, fd->record, &off); keylen = hfs_brec_keylen(bnode, fd->record); if (keylen == 0) { res = -EINVAL; goto out; } fd->keyoffset = off; fd->keylength = keylen; fd->entryoffset = off + keylen; fd->entrylength = len - keylen; hfs_bnode_read(bnode, fd->key, off, keylen); out: fd->bnode = bnode; return res; } Linus Torvalds <torvalds@linux-foundation.org>2016-12-12 20:50:02 -0800 committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-12 20:50:02 -0800 commite34bac726d27056081d0250c0e173e4b155aa340 (patch) tree85607d0b3b185380fb3267866020c6a4372b9298 /include/net/nfc/nci.h parentfe6bce8d30a86c693bf7cfbf4759cbafd121289f (diff)parent39a0e975c37dee93fa1b8ea5f7eacd1c4c8a586e (diff)
Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton: - various misc bits - most of MM (quite a lot of MM material is awaiting the merge of linux-next dependencies) - kasan - printk updates - procfs updates - MAINTAINERS - /lib updates - checkpatch updates * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (123 commits) init: reduce rootwait polling interval time to 5ms binfmt_elf: use vmalloc() for allocation of vma_filesz checkpatch: don't emit unified-diff error for rename-only patches checkpatch: don't check c99 types like uint8_t under tools checkpatch: avoid multiple line dereferences checkpatch: don't check .pl files, improve absolute path commit log test scripts/checkpatch.pl: fix spelling checkpatch: don't try to get maintained status when --no-tree is given lib/ida: document locking requirements a bit better lib/rbtree.c: fix typo in comment of ____rb_erase_color lib/Kconfig.debug: make CONFIG_STRICT_DEVMEM depend on CONFIG_DEVMEM MAINTAINERS: add drm and drm/i915 irc channels MAINTAINERS: add "C:" for URI for chat where developers hang out MAINTAINERS: add drm and drm/i915 bug filing info MAINTAINERS: add "B:" for URI where to file bugs get_maintainer: look for arbitrary letter prefixes in sections printk: add Kconfig option to set default console loglevel printk/sound: handle more message headers printk/btrfs: handle more message headers printk/kdb: handle more message headers ...
Diffstat (limited to 'include/net/nfc/nci.h')