![Al Viro](/assets/img/avatar_default.png)
- added typedef unsigned int __nocast gfp_t; - replaced __nocast uses for gfp flags with gfp_t - it gives exactly the same warnings as far as sparse is concerned, doesn't change generated code (from gcc point of view we replaced unsigned int with typedef) and documents what's going on far better. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
814 lines
19 KiB
C
814 lines
19 KiB
C
/*
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* Copyright (C) 2001 Momchil Velikov
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* Portions Copyright (C) 2001 Christoph Hellwig
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* Copyright (C) 2005 SGI, Christoph Lameter <clameter@sgi.com>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2, or (at
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* your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#include <linux/errno.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/radix-tree.h>
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#include <linux/percpu.h>
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#include <linux/slab.h>
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#include <linux/notifier.h>
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#include <linux/cpu.h>
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#include <linux/gfp.h>
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#include <linux/string.h>
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#include <linux/bitops.h>
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#ifdef __KERNEL__
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#define RADIX_TREE_MAP_SHIFT 6
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#else
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#define RADIX_TREE_MAP_SHIFT 3 /* For more stressful testing */
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#endif
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#define RADIX_TREE_TAGS 2
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#define RADIX_TREE_MAP_SIZE (1UL << RADIX_TREE_MAP_SHIFT)
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#define RADIX_TREE_MAP_MASK (RADIX_TREE_MAP_SIZE-1)
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#define RADIX_TREE_TAG_LONGS \
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((RADIX_TREE_MAP_SIZE + BITS_PER_LONG - 1) / BITS_PER_LONG)
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struct radix_tree_node {
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unsigned int count;
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void *slots[RADIX_TREE_MAP_SIZE];
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unsigned long tags[RADIX_TREE_TAGS][RADIX_TREE_TAG_LONGS];
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};
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struct radix_tree_path {
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struct radix_tree_node *node;
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int offset;
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};
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#define RADIX_TREE_INDEX_BITS (8 /* CHAR_BIT */ * sizeof(unsigned long))
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#define RADIX_TREE_MAX_PATH (RADIX_TREE_INDEX_BITS/RADIX_TREE_MAP_SHIFT + 2)
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static unsigned long height_to_maxindex[RADIX_TREE_MAX_PATH] __read_mostly;
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/*
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* Radix tree node cache.
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*/
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static kmem_cache_t *radix_tree_node_cachep;
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/*
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* Per-cpu pool of preloaded nodes
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*/
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struct radix_tree_preload {
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int nr;
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struct radix_tree_node *nodes[RADIX_TREE_MAX_PATH];
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};
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DEFINE_PER_CPU(struct radix_tree_preload, radix_tree_preloads) = { 0, };
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/*
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* This assumes that the caller has performed appropriate preallocation, and
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* that the caller has pinned this thread of control to the current CPU.
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*/
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static struct radix_tree_node *
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radix_tree_node_alloc(struct radix_tree_root *root)
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{
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struct radix_tree_node *ret;
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ret = kmem_cache_alloc(radix_tree_node_cachep, root->gfp_mask);
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if (ret == NULL && !(root->gfp_mask & __GFP_WAIT)) {
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struct radix_tree_preload *rtp;
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rtp = &__get_cpu_var(radix_tree_preloads);
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if (rtp->nr) {
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ret = rtp->nodes[rtp->nr - 1];
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rtp->nodes[rtp->nr - 1] = NULL;
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rtp->nr--;
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}
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}
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return ret;
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}
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static inline void
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radix_tree_node_free(struct radix_tree_node *node)
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{
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kmem_cache_free(radix_tree_node_cachep, node);
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}
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/*
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* Load up this CPU's radix_tree_node buffer with sufficient objects to
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* ensure that the addition of a single element in the tree cannot fail. On
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* success, return zero, with preemption disabled. On error, return -ENOMEM
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* with preemption not disabled.
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*/
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int radix_tree_preload(gfp_t gfp_mask)
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{
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struct radix_tree_preload *rtp;
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struct radix_tree_node *node;
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int ret = -ENOMEM;
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preempt_disable();
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rtp = &__get_cpu_var(radix_tree_preloads);
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while (rtp->nr < ARRAY_SIZE(rtp->nodes)) {
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preempt_enable();
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node = kmem_cache_alloc(radix_tree_node_cachep, gfp_mask);
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if (node == NULL)
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goto out;
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preempt_disable();
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rtp = &__get_cpu_var(radix_tree_preloads);
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if (rtp->nr < ARRAY_SIZE(rtp->nodes))
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rtp->nodes[rtp->nr++] = node;
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else
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kmem_cache_free(radix_tree_node_cachep, node);
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}
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ret = 0;
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out:
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return ret;
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}
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static inline void tag_set(struct radix_tree_node *node, int tag, int offset)
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{
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if (!test_bit(offset, &node->tags[tag][0]))
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__set_bit(offset, &node->tags[tag][0]);
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}
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static inline void tag_clear(struct radix_tree_node *node, int tag, int offset)
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{
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__clear_bit(offset, &node->tags[tag][0]);
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}
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static inline int tag_get(struct radix_tree_node *node, int tag, int offset)
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{
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return test_bit(offset, &node->tags[tag][0]);
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}
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/*
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* Return the maximum key which can be store into a
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* radix tree with height HEIGHT.
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*/
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static inline unsigned long radix_tree_maxindex(unsigned int height)
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{
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return height_to_maxindex[height];
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}
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/*
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* Extend a radix tree so it can store key @index.
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*/
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static int radix_tree_extend(struct radix_tree_root *root, unsigned long index)
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{
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struct radix_tree_node *node;
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unsigned int height;
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char tags[RADIX_TREE_TAGS];
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int tag;
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/* Figure out what the height should be. */
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height = root->height + 1;
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while (index > radix_tree_maxindex(height))
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height++;
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if (root->rnode == NULL) {
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root->height = height;
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goto out;
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}
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/*
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* Prepare the tag status of the top-level node for propagation
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* into the newly-pushed top-level node(s)
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*/
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for (tag = 0; tag < RADIX_TREE_TAGS; tag++) {
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int idx;
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tags[tag] = 0;
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for (idx = 0; idx < RADIX_TREE_TAG_LONGS; idx++) {
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if (root->rnode->tags[tag][idx]) {
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tags[tag] = 1;
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break;
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}
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}
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}
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do {
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if (!(node = radix_tree_node_alloc(root)))
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return -ENOMEM;
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/* Increase the height. */
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node->slots[0] = root->rnode;
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/* Propagate the aggregated tag info into the new root */
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for (tag = 0; tag < RADIX_TREE_TAGS; tag++) {
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if (tags[tag])
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tag_set(node, tag, 0);
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}
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node->count = 1;
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root->rnode = node;
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root->height++;
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} while (height > root->height);
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out:
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return 0;
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}
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/**
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* radix_tree_insert - insert into a radix tree
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* @root: radix tree root
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* @index: index key
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* @item: item to insert
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*
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* Insert an item into the radix tree at position @index.
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*/
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int radix_tree_insert(struct radix_tree_root *root,
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unsigned long index, void *item)
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{
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struct radix_tree_node *node = NULL, *slot;
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unsigned int height, shift;
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int offset;
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int error;
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/* Make sure the tree is high enough. */
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if ((!index && !root->rnode) ||
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index > radix_tree_maxindex(root->height)) {
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error = radix_tree_extend(root, index);
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if (error)
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return error;
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}
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slot = root->rnode;
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height = root->height;
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shift = (height-1) * RADIX_TREE_MAP_SHIFT;
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offset = 0; /* uninitialised var warning */
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while (height > 0) {
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if (slot == NULL) {
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/* Have to add a child node. */
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if (!(slot = radix_tree_node_alloc(root)))
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return -ENOMEM;
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if (node) {
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node->slots[offset] = slot;
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node->count++;
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} else
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root->rnode = slot;
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}
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/* Go a level down */
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offset = (index >> shift) & RADIX_TREE_MAP_MASK;
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node = slot;
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slot = node->slots[offset];
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shift -= RADIX_TREE_MAP_SHIFT;
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height--;
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}
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if (slot != NULL)
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return -EEXIST;
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if (node) {
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node->count++;
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node->slots[offset] = item;
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BUG_ON(tag_get(node, 0, offset));
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BUG_ON(tag_get(node, 1, offset));
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} else
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root->rnode = item;
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return 0;
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}
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EXPORT_SYMBOL(radix_tree_insert);
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/**
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* radix_tree_lookup - perform lookup operation on a radix tree
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* @root: radix tree root
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* @index: index key
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*
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* Lookup the item at the position @index in the radix tree @root.
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*/
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void *radix_tree_lookup(struct radix_tree_root *root, unsigned long index)
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{
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unsigned int height, shift;
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struct radix_tree_node *slot;
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height = root->height;
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if (index > radix_tree_maxindex(height))
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return NULL;
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shift = (height-1) * RADIX_TREE_MAP_SHIFT;
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slot = root->rnode;
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while (height > 0) {
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if (slot == NULL)
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return NULL;
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slot = slot->slots[(index >> shift) & RADIX_TREE_MAP_MASK];
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shift -= RADIX_TREE_MAP_SHIFT;
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height--;
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}
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return slot;
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}
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EXPORT_SYMBOL(radix_tree_lookup);
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/**
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* radix_tree_tag_set - set a tag on a radix tree node
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* @root: radix tree root
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* @index: index key
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* @tag: tag index
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*
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* Set the search tag corresponging to @index in the radix tree. From
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* the root all the way down to the leaf node.
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*
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* Returns the address of the tagged item. Setting a tag on a not-present
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* item is a bug.
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*/
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void *radix_tree_tag_set(struct radix_tree_root *root,
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unsigned long index, int tag)
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{
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unsigned int height, shift;
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struct radix_tree_node *slot;
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height = root->height;
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if (index > radix_tree_maxindex(height))
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return NULL;
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shift = (height - 1) * RADIX_TREE_MAP_SHIFT;
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slot = root->rnode;
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while (height > 0) {
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int offset;
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offset = (index >> shift) & RADIX_TREE_MAP_MASK;
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tag_set(slot, tag, offset);
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slot = slot->slots[offset];
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BUG_ON(slot == NULL);
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shift -= RADIX_TREE_MAP_SHIFT;
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height--;
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}
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return slot;
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}
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EXPORT_SYMBOL(radix_tree_tag_set);
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/**
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* radix_tree_tag_clear - clear a tag on a radix tree node
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* @root: radix tree root
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* @index: index key
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* @tag: tag index
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*
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* Clear the search tag corresponging to @index in the radix tree. If
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* this causes the leaf node to have no tags set then clear the tag in the
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* next-to-leaf node, etc.
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*
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* Returns the address of the tagged item on success, else NULL. ie:
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* has the same return value and semantics as radix_tree_lookup().
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*/
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void *radix_tree_tag_clear(struct radix_tree_root *root,
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unsigned long index, int tag)
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{
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struct radix_tree_path path[RADIX_TREE_MAX_PATH], *pathp = path;
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struct radix_tree_node *slot;
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unsigned int height, shift;
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void *ret = NULL;
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height = root->height;
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if (index > radix_tree_maxindex(height))
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goto out;
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shift = (height - 1) * RADIX_TREE_MAP_SHIFT;
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pathp->node = NULL;
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slot = root->rnode;
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while (height > 0) {
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int offset;
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if (slot == NULL)
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goto out;
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offset = (index >> shift) & RADIX_TREE_MAP_MASK;
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pathp[1].offset = offset;
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pathp[1].node = slot;
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slot = slot->slots[offset];
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pathp++;
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shift -= RADIX_TREE_MAP_SHIFT;
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height--;
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}
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ret = slot;
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if (ret == NULL)
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goto out;
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do {
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int idx;
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tag_clear(pathp->node, tag, pathp->offset);
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for (idx = 0; idx < RADIX_TREE_TAG_LONGS; idx++) {
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if (pathp->node->tags[tag][idx])
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goto out;
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}
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pathp--;
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} while (pathp->node);
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out:
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return ret;
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}
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EXPORT_SYMBOL(radix_tree_tag_clear);
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#ifndef __KERNEL__ /* Only the test harness uses this at present */
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/**
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* radix_tree_tag_get - get a tag on a radix tree node
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* @root: radix tree root
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* @index: index key
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* @tag: tag index
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*
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* Return values:
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*
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* 0: tag not present
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* 1: tag present, set
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* -1: tag present, unset
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*/
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int radix_tree_tag_get(struct radix_tree_root *root,
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unsigned long index, int tag)
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{
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unsigned int height, shift;
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struct radix_tree_node *slot;
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int saw_unset_tag = 0;
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height = root->height;
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if (index > radix_tree_maxindex(height))
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return 0;
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shift = (height - 1) * RADIX_TREE_MAP_SHIFT;
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slot = root->rnode;
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for ( ; ; ) {
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int offset;
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if (slot == NULL)
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return 0;
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offset = (index >> shift) & RADIX_TREE_MAP_MASK;
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/*
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* This is just a debug check. Later, we can bale as soon as
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* we see an unset tag.
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*/
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if (!tag_get(slot, tag, offset))
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saw_unset_tag = 1;
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if (height == 1) {
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int ret = tag_get(slot, tag, offset);
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BUG_ON(ret && saw_unset_tag);
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return ret ? 1 : -1;
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}
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slot = slot->slots[offset];
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shift -= RADIX_TREE_MAP_SHIFT;
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height--;
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}
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}
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EXPORT_SYMBOL(radix_tree_tag_get);
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#endif
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static unsigned int
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__lookup(struct radix_tree_root *root, void **results, unsigned long index,
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unsigned int max_items, unsigned long *next_index)
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{
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unsigned int nr_found = 0;
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unsigned int shift, height;
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struct radix_tree_node *slot;
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unsigned long i;
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height = root->height;
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if (height == 0)
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goto out;
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shift = (height-1) * RADIX_TREE_MAP_SHIFT;
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slot = root->rnode;
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for ( ; height > 1; height--) {
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for (i = (index >> shift) & RADIX_TREE_MAP_MASK ;
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i < RADIX_TREE_MAP_SIZE; i++) {
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if (slot->slots[i] != NULL)
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break;
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index &= ~((1UL << shift) - 1);
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index += 1UL << shift;
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if (index == 0)
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goto out; /* 32-bit wraparound */
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}
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if (i == RADIX_TREE_MAP_SIZE)
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goto out;
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shift -= RADIX_TREE_MAP_SHIFT;
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slot = slot->slots[i];
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}
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/* Bottom level: grab some items */
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for (i = index & RADIX_TREE_MAP_MASK; i < RADIX_TREE_MAP_SIZE; i++) {
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index++;
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if (slot->slots[i]) {
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results[nr_found++] = slot->slots[i];
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if (nr_found == max_items)
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goto out;
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}
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}
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out:
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*next_index = index;
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return nr_found;
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}
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/**
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* radix_tree_gang_lookup - perform multiple lookup on a radix tree
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* @root: radix tree root
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* @results: where the results of the lookup are placed
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* @first_index: start the lookup from this key
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* @max_items: place up to this many items at *results
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*
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* Performs an index-ascending scan of the tree for present items. Places
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* them at *@results and returns the number of items which were placed at
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* *@results.
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*
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* The implementation is naive.
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*/
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unsigned int
|
|
radix_tree_gang_lookup(struct radix_tree_root *root, void **results,
|
|
unsigned long first_index, unsigned int max_items)
|
|
{
|
|
const unsigned long max_index = radix_tree_maxindex(root->height);
|
|
unsigned long cur_index = first_index;
|
|
unsigned int ret = 0;
|
|
|
|
while (ret < max_items) {
|
|
unsigned int nr_found;
|
|
unsigned long next_index; /* Index of next search */
|
|
|
|
if (cur_index > max_index)
|
|
break;
|
|
nr_found = __lookup(root, results + ret, cur_index,
|
|
max_items - ret, &next_index);
|
|
ret += nr_found;
|
|
if (next_index == 0)
|
|
break;
|
|
cur_index = next_index;
|
|
}
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(radix_tree_gang_lookup);
|
|
|
|
/*
|
|
* FIXME: the two tag_get()s here should use find_next_bit() instead of
|
|
* open-coding the search.
|
|
*/
|
|
static unsigned int
|
|
__lookup_tag(struct radix_tree_root *root, void **results, unsigned long index,
|
|
unsigned int max_items, unsigned long *next_index, int tag)
|
|
{
|
|
unsigned int nr_found = 0;
|
|
unsigned int shift;
|
|
unsigned int height = root->height;
|
|
struct radix_tree_node *slot;
|
|
|
|
shift = (height - 1) * RADIX_TREE_MAP_SHIFT;
|
|
slot = root->rnode;
|
|
|
|
while (height > 0) {
|
|
unsigned long i = (index >> shift) & RADIX_TREE_MAP_MASK;
|
|
|
|
for ( ; i < RADIX_TREE_MAP_SIZE; i++) {
|
|
if (tag_get(slot, tag, i)) {
|
|
BUG_ON(slot->slots[i] == NULL);
|
|
break;
|
|
}
|
|
index &= ~((1UL << shift) - 1);
|
|
index += 1UL << shift;
|
|
if (index == 0)
|
|
goto out; /* 32-bit wraparound */
|
|
}
|
|
if (i == RADIX_TREE_MAP_SIZE)
|
|
goto out;
|
|
height--;
|
|
if (height == 0) { /* Bottom level: grab some items */
|
|
unsigned long j = index & RADIX_TREE_MAP_MASK;
|
|
|
|
for ( ; j < RADIX_TREE_MAP_SIZE; j++) {
|
|
index++;
|
|
if (tag_get(slot, tag, j)) {
|
|
BUG_ON(slot->slots[j] == NULL);
|
|
results[nr_found++] = slot->slots[j];
|
|
if (nr_found == max_items)
|
|
goto out;
|
|
}
|
|
}
|
|
}
|
|
shift -= RADIX_TREE_MAP_SHIFT;
|
|
slot = slot->slots[i];
|
|
}
|
|
out:
|
|
*next_index = index;
|
|
return nr_found;
|
|
}
|
|
|
|
/**
|
|
* radix_tree_gang_lookup_tag - perform multiple lookup on a radix tree
|
|
* based on a tag
|
|
* @root: radix tree root
|
|
* @results: where the results of the lookup are placed
|
|
* @first_index: start the lookup from this key
|
|
* @max_items: place up to this many items at *results
|
|
* @tag: the tag index
|
|
*
|
|
* Performs an index-ascending scan of the tree for present items which
|
|
* have the tag indexed by @tag set. Places the items at *@results and
|
|
* returns the number of items which were placed at *@results.
|
|
*/
|
|
unsigned int
|
|
radix_tree_gang_lookup_tag(struct radix_tree_root *root, void **results,
|
|
unsigned long first_index, unsigned int max_items, int tag)
|
|
{
|
|
const unsigned long max_index = radix_tree_maxindex(root->height);
|
|
unsigned long cur_index = first_index;
|
|
unsigned int ret = 0;
|
|
|
|
while (ret < max_items) {
|
|
unsigned int nr_found;
|
|
unsigned long next_index; /* Index of next search */
|
|
|
|
if (cur_index > max_index)
|
|
break;
|
|
nr_found = __lookup_tag(root, results + ret, cur_index,
|
|
max_items - ret, &next_index, tag);
|
|
ret += nr_found;
|
|
if (next_index == 0)
|
|
break;
|
|
cur_index = next_index;
|
|
}
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(radix_tree_gang_lookup_tag);
|
|
|
|
/**
|
|
* radix_tree_delete - delete an item from a radix tree
|
|
* @root: radix tree root
|
|
* @index: index key
|
|
*
|
|
* Remove the item at @index from the radix tree rooted at @root.
|
|
*
|
|
* Returns the address of the deleted item, or NULL if it was not present.
|
|
*/
|
|
void *radix_tree_delete(struct radix_tree_root *root, unsigned long index)
|
|
{
|
|
struct radix_tree_path path[RADIX_TREE_MAX_PATH], *pathp = path;
|
|
struct radix_tree_path *orig_pathp;
|
|
struct radix_tree_node *slot;
|
|
unsigned int height, shift;
|
|
void *ret = NULL;
|
|
char tags[RADIX_TREE_TAGS];
|
|
int nr_cleared_tags;
|
|
|
|
height = root->height;
|
|
if (index > radix_tree_maxindex(height))
|
|
goto out;
|
|
|
|
shift = (height - 1) * RADIX_TREE_MAP_SHIFT;
|
|
pathp->node = NULL;
|
|
slot = root->rnode;
|
|
|
|
for ( ; height > 0; height--) {
|
|
int offset;
|
|
|
|
if (slot == NULL)
|
|
goto out;
|
|
|
|
offset = (index >> shift) & RADIX_TREE_MAP_MASK;
|
|
pathp[1].offset = offset;
|
|
pathp[1].node = slot;
|
|
slot = slot->slots[offset];
|
|
pathp++;
|
|
shift -= RADIX_TREE_MAP_SHIFT;
|
|
}
|
|
|
|
ret = slot;
|
|
if (ret == NULL)
|
|
goto out;
|
|
|
|
orig_pathp = pathp;
|
|
|
|
/*
|
|
* Clear all tags associated with the just-deleted item
|
|
*/
|
|
memset(tags, 0, sizeof(tags));
|
|
do {
|
|
int tag;
|
|
|
|
nr_cleared_tags = RADIX_TREE_TAGS;
|
|
for (tag = 0; tag < RADIX_TREE_TAGS; tag++) {
|
|
int idx;
|
|
|
|
if (tags[tag])
|
|
continue;
|
|
|
|
tag_clear(pathp->node, tag, pathp->offset);
|
|
|
|
for (idx = 0; idx < RADIX_TREE_TAG_LONGS; idx++) {
|
|
if (pathp->node->tags[tag][idx]) {
|
|
tags[tag] = 1;
|
|
nr_cleared_tags--;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
pathp--;
|
|
} while (pathp->node && nr_cleared_tags);
|
|
|
|
/* Now free the nodes we do not need anymore */
|
|
for (pathp = orig_pathp; pathp->node; pathp--) {
|
|
pathp->node->slots[pathp->offset] = NULL;
|
|
if (--pathp->node->count)
|
|
goto out;
|
|
|
|
/* Node with zero slots in use so free it */
|
|
radix_tree_node_free(pathp->node);
|
|
}
|
|
root->rnode = NULL;
|
|
root->height = 0;
|
|
out:
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(radix_tree_delete);
|
|
|
|
/**
|
|
* radix_tree_tagged - test whether any items in the tree are tagged
|
|
* @root: radix tree root
|
|
* @tag: tag to test
|
|
*/
|
|
int radix_tree_tagged(struct radix_tree_root *root, int tag)
|
|
{
|
|
int idx;
|
|
|
|
if (!root->rnode)
|
|
return 0;
|
|
for (idx = 0; idx < RADIX_TREE_TAG_LONGS; idx++) {
|
|
if (root->rnode->tags[tag][idx])
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(radix_tree_tagged);
|
|
|
|
static void
|
|
radix_tree_node_ctor(void *node, kmem_cache_t *cachep, unsigned long flags)
|
|
{
|
|
memset(node, 0, sizeof(struct radix_tree_node));
|
|
}
|
|
|
|
static __init unsigned long __maxindex(unsigned int height)
|
|
{
|
|
unsigned int tmp = height * RADIX_TREE_MAP_SHIFT;
|
|
unsigned long index = (~0UL >> (RADIX_TREE_INDEX_BITS - tmp - 1)) >> 1;
|
|
|
|
if (tmp >= RADIX_TREE_INDEX_BITS)
|
|
index = ~0UL;
|
|
return index;
|
|
}
|
|
|
|
static __init void radix_tree_init_maxindex(void)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(height_to_maxindex); i++)
|
|
height_to_maxindex[i] = __maxindex(i);
|
|
}
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
static int radix_tree_callback(struct notifier_block *nfb,
|
|
unsigned long action,
|
|
void *hcpu)
|
|
{
|
|
int cpu = (long)hcpu;
|
|
struct radix_tree_preload *rtp;
|
|
|
|
/* Free per-cpu pool of perloaded nodes */
|
|
if (action == CPU_DEAD) {
|
|
rtp = &per_cpu(radix_tree_preloads, cpu);
|
|
while (rtp->nr) {
|
|
kmem_cache_free(radix_tree_node_cachep,
|
|
rtp->nodes[rtp->nr-1]);
|
|
rtp->nodes[rtp->nr-1] = NULL;
|
|
rtp->nr--;
|
|
}
|
|
}
|
|
return NOTIFY_OK;
|
|
}
|
|
#endif /* CONFIG_HOTPLUG_CPU */
|
|
|
|
void __init radix_tree_init(void)
|
|
{
|
|
radix_tree_node_cachep = kmem_cache_create("radix_tree_node",
|
|
sizeof(struct radix_tree_node), 0,
|
|
SLAB_PANIC, radix_tree_node_ctor, NULL);
|
|
radix_tree_init_maxindex();
|
|
hotcpu_notifier(radix_tree_callback, 0);
|
|
}
|