2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/sched.h>
22 #include "print-tree.h"
23 #include "transaction.h"
25 static void reada_defrag(struct btrfs_root *root,
26 struct extent_buffer *node)
34 blocksize = btrfs_level_size(root, btrfs_header_level(node) - 1);
35 nritems = btrfs_header_nritems(node);
36 for (i = 0; i < nritems; i++) {
37 bytenr = btrfs_node_blockptr(node, i);
38 ret = readahead_tree_block(root, bytenr, blocksize);
44 static int defrag_walk_down(struct btrfs_trans_handle *trans,
45 struct btrfs_root *root,
46 struct btrfs_path *path, int *level,
47 int cache_only, u64 *last_ret)
49 struct extent_buffer *next;
50 struct extent_buffer *cur;
56 WARN_ON(*level >= BTRFS_MAX_LEVEL);
58 if (root->fs_info->extent_root == root)
61 if (*level == 1 && cache_only && path->nodes[1] &&
62 !btrfs_buffer_defrag(path->nodes[1])) {
67 WARN_ON(*level >= BTRFS_MAX_LEVEL);
68 cur = path->nodes[*level];
70 if (!cache_only && *level > 1 && path->slots[*level] == 0)
71 reada_defrag(root, cur);
73 if (btrfs_header_level(cur) != *level)
76 if (path->slots[*level] >=
77 btrfs_header_nritems(cur))
81 WARN_ON(btrfs_header_generation(path->nodes[*level]) !=
83 ret = btrfs_realloc_node(trans, root,
87 &root->defrag_progress);
89 btrfs_extent_post_op(trans, root);
93 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
96 next = btrfs_find_tree_block(root, bytenr,
97 btrfs_level_size(root, *level - 1));
98 if (!next || !btrfs_buffer_uptodate(next) ||
99 !btrfs_buffer_defrag(next)) {
100 free_extent_buffer(next);
101 path->slots[*level]++;
105 next = read_tree_block(root, bytenr,
106 btrfs_level_size(root, *level - 1));
108 ret = btrfs_cow_block(trans, root, next, path->nodes[*level],
109 path->slots[*level], &next);
112 btrfs_extent_post_op(trans, root);
114 WARN_ON(*level <= 0);
115 if (path->nodes[*level-1])
116 free_extent_buffer(path->nodes[*level-1]);
117 path->nodes[*level-1] = next;
118 *level = btrfs_header_level(next);
119 path->slots[*level] = 0;
122 WARN_ON(*level >= BTRFS_MAX_LEVEL);
124 btrfs_clear_buffer_defrag(path->nodes[*level]);
126 free_extent_buffer(path->nodes[*level]);
127 path->nodes[*level] = NULL;
129 WARN_ON(ret && ret != -EAGAIN);
133 static int defrag_walk_up(struct btrfs_trans_handle *trans,
134 struct btrfs_root *root,
135 struct btrfs_path *path, int *level,
140 struct extent_buffer *node;
142 for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
143 slot = path->slots[i];
144 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
147 node = path->nodes[i];
149 btrfs_node_key_to_cpu(node, &root->defrag_progress,
151 root->defrag_level = i;
154 btrfs_clear_buffer_defrag(path->nodes[*level]);
155 free_extent_buffer(path->nodes[*level]);
156 path->nodes[*level] = NULL;
163 int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
164 struct btrfs_root *root, int cache_only)
166 struct btrfs_path *path = NULL;
167 struct extent_buffer *tmp;
176 if (root->fs_info->extent_root == root)
179 if (root->ref_cows == 0 && !is_extent)
182 path = btrfs_alloc_path();
186 level = btrfs_header_level(root->node);
192 if (root->defrag_progress.objectid == 0) {
193 extent_buffer_get(root->node);
194 ret = btrfs_cow_block(trans, root, root->node, NULL, 0, &tmp);
196 path->nodes[level] = root->node;
197 path->slots[level] = 0;
199 btrfs_extent_post_op(trans, root);
201 level = root->defrag_level;
202 path->lowest_level = level;
203 wret = btrfs_search_slot(trans, root, &root->defrag_progress,
207 btrfs_extent_post_op(trans, root);
214 while(level > 0 && !path->nodes[level])
217 if (!path->nodes[level]) {
224 wret = defrag_walk_down(trans, root, path, &level, cache_only,
231 wret = defrag_walk_up(trans, root, path, &level, cache_only);
240 for (i = 0; i <= orig_level; i++) {
241 if (path->nodes[i]) {
242 free_extent_buffer(path->nodes[i]);
243 path->nodes[i] = NULL;
248 btrfs_free_path(path);
249 if (ret != -EAGAIN) {
250 memset(&root->defrag_progress, 0,
251 sizeof(root->defrag_progress));