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 ret = btrfs_realloc_node(trans, root,
85 &root->defrag_progress);
87 btrfs_extent_post_op(trans, root);
91 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
94 next = btrfs_find_tree_block(root, bytenr,
95 btrfs_level_size(root, *level - 1));
96 if (!next || !btrfs_buffer_uptodate(next) ||
97 !btrfs_buffer_defrag(next)) {
98 free_extent_buffer(next);
99 path->slots[*level]++;
103 next = read_tree_block(root, bytenr,
104 btrfs_level_size(root, *level - 1));
106 ret = btrfs_cow_block(trans, root, next, path->nodes[*level],
107 path->slots[*level], &next);
110 btrfs_extent_post_op(trans, root);
112 WARN_ON(*level <= 0);
113 if (path->nodes[*level-1])
114 free_extent_buffer(path->nodes[*level-1]);
115 path->nodes[*level-1] = next;
116 *level = btrfs_header_level(next);
117 path->slots[*level] = 0;
120 WARN_ON(*level >= BTRFS_MAX_LEVEL);
122 btrfs_clear_buffer_defrag(path->nodes[*level]);
124 free_extent_buffer(path->nodes[*level]);
125 path->nodes[*level] = NULL;
127 WARN_ON(ret && ret != -EAGAIN);
131 static int defrag_walk_up(struct btrfs_trans_handle *trans,
132 struct btrfs_root *root,
133 struct btrfs_path *path, int *level,
138 struct extent_buffer *node;
140 for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
141 slot = path->slots[i];
142 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
145 node = path->nodes[i];
147 btrfs_node_key_to_cpu(node, &root->defrag_progress,
149 root->defrag_level = i;
152 btrfs_clear_buffer_defrag(path->nodes[*level]);
153 free_extent_buffer(path->nodes[*level]);
154 path->nodes[*level] = NULL;
161 int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
162 struct btrfs_root *root, int cache_only)
164 struct btrfs_path *path = NULL;
165 struct extent_buffer *tmp;
174 if (root->fs_info->extent_root == root)
177 if (root->ref_cows == 0 && !is_extent)
180 path = btrfs_alloc_path();
184 level = btrfs_header_level(root->node);
190 if (root->defrag_progress.objectid == 0) {
191 extent_buffer_get(root->node);
192 ret = btrfs_cow_block(trans, root, root->node, NULL, 0, &tmp);
194 path->nodes[level] = root->node;
195 path->slots[level] = 0;
197 btrfs_extent_post_op(trans, root);
199 level = root->defrag_level;
200 path->lowest_level = level;
201 wret = btrfs_search_slot(trans, root, &root->defrag_progress,
205 btrfs_extent_post_op(trans, root);
212 while(level > 0 && !path->nodes[level])
215 if (!path->nodes[level]) {
222 wret = defrag_walk_down(trans, root, path, &level, cache_only,
229 wret = defrag_walk_up(trans, root, path, &level, cache_only);
238 for (i = 0; i <= orig_level; i++) {
239 if (path->nodes[i]) {
240 free_extent_buffer(path->nodes[i]);
241 path->nodes[i] = NULL;
246 btrfs_free_path(path);
247 if (ret != -EAGAIN) {
248 memset(&root->defrag_progress, 0,
249 sizeof(root->defrag_progress));