Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 1 | /* |
| 2 | * fs/ext4/extents_status.c |
| 3 | * |
| 4 | * Written by Yongqiang Yang <xiaoqiangnk@gmail.com> |
| 5 | * Modified by |
| 6 | * Allison Henderson <achender@linux.vnet.ibm.com> |
| 7 | * Hugh Dickins <hughd@google.com> |
| 8 | * Zheng Liu <wenqing.lz@taobao.com> |
| 9 | * |
| 10 | * Ext4 extents status tree core functions. |
| 11 | */ |
| 12 | #include <linux/rbtree.h> |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 13 | #include <linux/list_sort.h> |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 14 | #include "ext4.h" |
| 15 | #include "extents_status.h" |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 16 | |
Zheng Liu | 992e9fd | 2012-11-08 21:57:33 -0500 | [diff] [blame] | 17 | #include <trace/events/ext4.h> |
| 18 | |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 19 | /* |
| 20 | * According to previous discussion in Ext4 Developer Workshop, we |
| 21 | * will introduce a new structure called io tree to track all extent |
| 22 | * status in order to solve some problems that we have met |
| 23 | * (e.g. Reservation space warning), and provide extent-level locking. |
| 24 | * Delay extent tree is the first step to achieve this goal. It is |
| 25 | * original built by Yongqiang Yang. At that time it is called delay |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 26 | * extent tree, whose goal is only track delayed extents in memory to |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 27 | * simplify the implementation of fiemap and bigalloc, and introduce |
| 28 | * lseek SEEK_DATA/SEEK_HOLE support. That is why it is still called |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 29 | * delay extent tree at the first commit. But for better understand |
| 30 | * what it does, it has been rename to extent status tree. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 31 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 32 | * Step1: |
| 33 | * Currently the first step has been done. All delayed extents are |
| 34 | * tracked in the tree. It maintains the delayed extent when a delayed |
| 35 | * allocation is issued, and the delayed extent is written out or |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 36 | * invalidated. Therefore the implementation of fiemap and bigalloc |
| 37 | * are simplified, and SEEK_DATA/SEEK_HOLE are introduced. |
| 38 | * |
| 39 | * The following comment describes the implemenmtation of extent |
| 40 | * status tree and future works. |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 41 | * |
| 42 | * Step2: |
| 43 | * In this step all extent status are tracked by extent status tree. |
| 44 | * Thus, we can first try to lookup a block mapping in this tree before |
| 45 | * finding it in extent tree. Hence, single extent cache can be removed |
| 46 | * because extent status tree can do a better job. Extents in status |
| 47 | * tree are loaded on-demand. Therefore, the extent status tree may not |
| 48 | * contain all of the extents in a file. Meanwhile we define a shrinker |
| 49 | * to reclaim memory from extent status tree because fragmented extent |
| 50 | * tree will make status tree cost too much memory. written/unwritten/- |
| 51 | * hole extents in the tree will be reclaimed by this shrinker when we |
| 52 | * are under high memory pressure. Delayed extents will not be |
| 53 | * reclimed because fiemap, bigalloc, and seek_data/hole need it. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 54 | */ |
| 55 | |
| 56 | /* |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 57 | * Extent status tree implementation for ext4. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 58 | * |
| 59 | * |
| 60 | * ========================================================================== |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 61 | * Extent status tree tracks all extent status. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 62 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 63 | * 1. Why we need to implement extent status tree? |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 64 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 65 | * Without extent status tree, ext4 identifies a delayed extent by looking |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 66 | * up page cache, this has several deficiencies - complicated, buggy, |
| 67 | * and inefficient code. |
| 68 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 69 | * FIEMAP, SEEK_HOLE/DATA, bigalloc, and writeout all need to know if a |
| 70 | * block or a range of blocks are belonged to a delayed extent. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 71 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 72 | * Let us have a look at how they do without extent status tree. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 73 | * -- FIEMAP |
| 74 | * FIEMAP looks up page cache to identify delayed allocations from holes. |
| 75 | * |
| 76 | * -- SEEK_HOLE/DATA |
| 77 | * SEEK_HOLE/DATA has the same problem as FIEMAP. |
| 78 | * |
| 79 | * -- bigalloc |
| 80 | * bigalloc looks up page cache to figure out if a block is |
| 81 | * already under delayed allocation or not to determine whether |
| 82 | * quota reserving is needed for the cluster. |
| 83 | * |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 84 | * -- writeout |
| 85 | * Writeout looks up whole page cache to see if a buffer is |
| 86 | * mapped, If there are not very many delayed buffers, then it is |
| 87 | * time comsuming. |
| 88 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 89 | * With extent status tree implementation, FIEMAP, SEEK_HOLE/DATA, |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 90 | * bigalloc and writeout can figure out if a block or a range of |
| 91 | * blocks is under delayed allocation(belonged to a delayed extent) or |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 92 | * not by searching the extent tree. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 93 | * |
| 94 | * |
| 95 | * ========================================================================== |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 96 | * 2. Ext4 extent status tree impelmentation |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 97 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 98 | * -- extent |
| 99 | * A extent is a range of blocks which are contiguous logically and |
| 100 | * physically. Unlike extent in extent tree, this extent in ext4 is |
| 101 | * a in-memory struct, there is no corresponding on-disk data. There |
| 102 | * is no limit on length of extent, so an extent can contain as many |
| 103 | * blocks as they are contiguous logically and physically. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 104 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 105 | * -- extent status tree |
| 106 | * Every inode has an extent status tree and all allocation blocks |
| 107 | * are added to the tree with different status. The extent in the |
| 108 | * tree are ordered by logical block no. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 109 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 110 | * -- operations on a extent status tree |
| 111 | * There are three important operations on a delayed extent tree: find |
| 112 | * next extent, adding a extent(a range of blocks) and removing a extent. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 113 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 114 | * -- race on a extent status tree |
| 115 | * Extent status tree is protected by inode->i_es_lock. |
| 116 | * |
| 117 | * -- memory consumption |
| 118 | * Fragmented extent tree will make extent status tree cost too much |
| 119 | * memory. Hence, we will reclaim written/unwritten/hole extents from |
| 120 | * the tree under a heavy memory pressure. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 121 | * |
| 122 | * |
| 123 | * ========================================================================== |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 124 | * 3. Performance analysis |
| 125 | * |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 126 | * -- overhead |
| 127 | * 1. There is a cache extent for write access, so if writes are |
| 128 | * not very random, adding space operaions are in O(1) time. |
| 129 | * |
| 130 | * -- gain |
| 131 | * 2. Code is much simpler, more readable, more maintainable and |
| 132 | * more efficient. |
| 133 | * |
| 134 | * |
| 135 | * ========================================================================== |
| 136 | * 4. TODO list |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 137 | * |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 138 | * -- Refactor delayed space reservation |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 139 | * |
| 140 | * -- Extent-level locking |
| 141 | */ |
| 142 | |
| 143 | static struct kmem_cache *ext4_es_cachep; |
| 144 | |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 145 | static int __es_insert_extent(struct inode *inode, struct extent_status *newes); |
| 146 | static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk, |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 147 | ext4_lblk_t end); |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 148 | static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei, |
| 149 | int nr_to_scan); |
Theodore Ts'o | e15f742 | 2013-07-15 00:12:14 -0400 | [diff] [blame] | 150 | static int __ext4_es_shrink(struct ext4_sb_info *sbi, int nr_to_scan, |
| 151 | struct ext4_inode_info *locked_ei); |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 152 | |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 153 | int __init ext4_init_es(void) |
| 154 | { |
Theodore Ts'o | 2463077 | 2013-02-28 23:58:56 -0500 | [diff] [blame] | 155 | ext4_es_cachep = kmem_cache_create("ext4_extent_status", |
| 156 | sizeof(struct extent_status), |
| 157 | 0, (SLAB_RECLAIM_ACCOUNT), NULL); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 158 | if (ext4_es_cachep == NULL) |
| 159 | return -ENOMEM; |
| 160 | return 0; |
| 161 | } |
| 162 | |
| 163 | void ext4_exit_es(void) |
| 164 | { |
| 165 | if (ext4_es_cachep) |
| 166 | kmem_cache_destroy(ext4_es_cachep); |
| 167 | } |
| 168 | |
| 169 | void ext4_es_init_tree(struct ext4_es_tree *tree) |
| 170 | { |
| 171 | tree->root = RB_ROOT; |
| 172 | tree->cache_es = NULL; |
| 173 | } |
| 174 | |
| 175 | #ifdef ES_DEBUG__ |
| 176 | static void ext4_es_print_tree(struct inode *inode) |
| 177 | { |
| 178 | struct ext4_es_tree *tree; |
| 179 | struct rb_node *node; |
| 180 | |
| 181 | printk(KERN_DEBUG "status extents for inode %lu:", inode->i_ino); |
| 182 | tree = &EXT4_I(inode)->i_es_tree; |
| 183 | node = rb_first(&tree->root); |
| 184 | while (node) { |
| 185 | struct extent_status *es; |
| 186 | es = rb_entry(node, struct extent_status, rb_node); |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 187 | printk(KERN_DEBUG " [%u/%u) %llu %llx", |
| 188 | es->es_lblk, es->es_len, |
| 189 | ext4_es_pblock(es), ext4_es_status(es)); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 190 | node = rb_next(node); |
| 191 | } |
| 192 | printk(KERN_DEBUG "\n"); |
| 193 | } |
| 194 | #else |
| 195 | #define ext4_es_print_tree(inode) |
| 196 | #endif |
| 197 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 198 | static inline ext4_lblk_t ext4_es_end(struct extent_status *es) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 199 | { |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 200 | BUG_ON(es->es_lblk + es->es_len < es->es_lblk); |
| 201 | return es->es_lblk + es->es_len - 1; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 202 | } |
| 203 | |
| 204 | /* |
| 205 | * search through the tree for an delayed extent with a given offset. If |
| 206 | * it can't be found, try to find next extent. |
| 207 | */ |
| 208 | static struct extent_status *__es_tree_search(struct rb_root *root, |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 209 | ext4_lblk_t lblk) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 210 | { |
| 211 | struct rb_node *node = root->rb_node; |
| 212 | struct extent_status *es = NULL; |
| 213 | |
| 214 | while (node) { |
| 215 | es = rb_entry(node, struct extent_status, rb_node); |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 216 | if (lblk < es->es_lblk) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 217 | node = node->rb_left; |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 218 | else if (lblk > ext4_es_end(es)) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 219 | node = node->rb_right; |
| 220 | else |
| 221 | return es; |
| 222 | } |
| 223 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 224 | if (es && lblk < es->es_lblk) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 225 | return es; |
| 226 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 227 | if (es && lblk > ext4_es_end(es)) { |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 228 | node = rb_next(&es->rb_node); |
| 229 | return node ? rb_entry(node, struct extent_status, rb_node) : |
| 230 | NULL; |
| 231 | } |
| 232 | |
| 233 | return NULL; |
| 234 | } |
| 235 | |
| 236 | /* |
Yan, Zheng | e30b5dc | 2013-05-03 02:15:52 -0400 | [diff] [blame] | 237 | * ext4_es_find_delayed_extent_range: find the 1st delayed extent covering |
| 238 | * @es->lblk if it exists, otherwise, the next extent after @es->lblk. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 239 | * |
| 240 | * @inode: the inode which owns delayed extents |
Zheng Liu | be40136 | 2013-02-18 00:27:26 -0500 | [diff] [blame] | 241 | * @lblk: the offset where we start to search |
Yan, Zheng | e30b5dc | 2013-05-03 02:15:52 -0400 | [diff] [blame] | 242 | * @end: the offset where we stop to search |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 243 | * @es: delayed extent that we found |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 244 | */ |
Yan, Zheng | e30b5dc | 2013-05-03 02:15:52 -0400 | [diff] [blame] | 245 | void ext4_es_find_delayed_extent_range(struct inode *inode, |
| 246 | ext4_lblk_t lblk, ext4_lblk_t end, |
Zheng Liu | be40136 | 2013-02-18 00:27:26 -0500 | [diff] [blame] | 247 | struct extent_status *es) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 248 | { |
| 249 | struct ext4_es_tree *tree = NULL; |
| 250 | struct extent_status *es1 = NULL; |
| 251 | struct rb_node *node; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 252 | |
Zheng Liu | be40136 | 2013-02-18 00:27:26 -0500 | [diff] [blame] | 253 | BUG_ON(es == NULL); |
Yan, Zheng | e30b5dc | 2013-05-03 02:15:52 -0400 | [diff] [blame] | 254 | BUG_ON(end < lblk); |
| 255 | trace_ext4_es_find_delayed_extent_range_enter(inode, lblk); |
Zheng Liu | 992e9fd | 2012-11-08 21:57:33 -0500 | [diff] [blame] | 256 | |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 257 | read_lock(&EXT4_I(inode)->i_es_lock); |
| 258 | tree = &EXT4_I(inode)->i_es_tree; |
| 259 | |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 260 | /* find extent in cache firstly */ |
Zheng Liu | be40136 | 2013-02-18 00:27:26 -0500 | [diff] [blame] | 261 | es->es_lblk = es->es_len = es->es_pblk = 0; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 262 | if (tree->cache_es) { |
| 263 | es1 = tree->cache_es; |
Zheng Liu | be40136 | 2013-02-18 00:27:26 -0500 | [diff] [blame] | 264 | if (in_range(lblk, es1->es_lblk, es1->es_len)) { |
Theodore Ts'o | 3be78c7 | 2013-08-16 21:22:41 -0400 | [diff] [blame] | 265 | es_debug("%u cached by [%u/%u) %llu %x\n", |
Zheng Liu | be40136 | 2013-02-18 00:27:26 -0500 | [diff] [blame] | 266 | lblk, es1->es_lblk, es1->es_len, |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 267 | ext4_es_pblock(es1), ext4_es_status(es1)); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 268 | goto out; |
| 269 | } |
| 270 | } |
| 271 | |
Zheng Liu | be40136 | 2013-02-18 00:27:26 -0500 | [diff] [blame] | 272 | es1 = __es_tree_search(&tree->root, lblk); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 273 | |
| 274 | out: |
Zheng Liu | be40136 | 2013-02-18 00:27:26 -0500 | [diff] [blame] | 275 | if (es1 && !ext4_es_is_delayed(es1)) { |
| 276 | while ((node = rb_next(&es1->rb_node)) != NULL) { |
| 277 | es1 = rb_entry(node, struct extent_status, rb_node); |
Yan, Zheng | e30b5dc | 2013-05-03 02:15:52 -0400 | [diff] [blame] | 278 | if (es1->es_lblk > end) { |
| 279 | es1 = NULL; |
| 280 | break; |
| 281 | } |
Zheng Liu | be40136 | 2013-02-18 00:27:26 -0500 | [diff] [blame] | 282 | if (ext4_es_is_delayed(es1)) |
| 283 | break; |
| 284 | } |
| 285 | } |
| 286 | |
| 287 | if (es1 && ext4_es_is_delayed(es1)) { |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 288 | tree->cache_es = es1; |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 289 | es->es_lblk = es1->es_lblk; |
| 290 | es->es_len = es1->es_len; |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 291 | es->es_pblk = es1->es_pblk; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 292 | } |
| 293 | |
| 294 | read_unlock(&EXT4_I(inode)->i_es_lock); |
Zheng Liu | 992e9fd | 2012-11-08 21:57:33 -0500 | [diff] [blame] | 295 | |
Yan, Zheng | e30b5dc | 2013-05-03 02:15:52 -0400 | [diff] [blame] | 296 | trace_ext4_es_find_delayed_extent_range_exit(inode, es); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 297 | } |
| 298 | |
| 299 | static struct extent_status * |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 300 | ext4_es_alloc_extent(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t len, |
| 301 | ext4_fsblk_t pblk) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 302 | { |
| 303 | struct extent_status *es; |
| 304 | es = kmem_cache_alloc(ext4_es_cachep, GFP_ATOMIC); |
| 305 | if (es == NULL) |
| 306 | return NULL; |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 307 | es->es_lblk = lblk; |
| 308 | es->es_len = len; |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 309 | es->es_pblk = pblk; |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 310 | |
| 311 | /* |
| 312 | * We don't count delayed extent because we never try to reclaim them |
| 313 | */ |
Theodore Ts'o | 2463077 | 2013-02-28 23:58:56 -0500 | [diff] [blame] | 314 | if (!ext4_es_is_delayed(es)) { |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 315 | EXT4_I(inode)->i_es_lru_nr++; |
Theodore Ts'o | 1ac6466 | 2013-03-02 10:27:46 -0500 | [diff] [blame] | 316 | percpu_counter_inc(&EXT4_SB(inode->i_sb)->s_extent_cache_cnt); |
Theodore Ts'o | 2463077 | 2013-02-28 23:58:56 -0500 | [diff] [blame] | 317 | } |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 318 | |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 319 | return es; |
| 320 | } |
| 321 | |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 322 | static void ext4_es_free_extent(struct inode *inode, struct extent_status *es) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 323 | { |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 324 | /* Decrease the lru counter when this es is not delayed */ |
| 325 | if (!ext4_es_is_delayed(es)) { |
| 326 | BUG_ON(EXT4_I(inode)->i_es_lru_nr == 0); |
| 327 | EXT4_I(inode)->i_es_lru_nr--; |
Theodore Ts'o | 1ac6466 | 2013-03-02 10:27:46 -0500 | [diff] [blame] | 328 | percpu_counter_dec(&EXT4_SB(inode->i_sb)->s_extent_cache_cnt); |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 329 | } |
| 330 | |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 331 | kmem_cache_free(ext4_es_cachep, es); |
| 332 | } |
| 333 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 334 | /* |
| 335 | * Check whether or not two extents can be merged |
| 336 | * Condition: |
| 337 | * - logical block number is contiguous |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 338 | * - physical block number is contiguous |
| 339 | * - status is equal |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 340 | */ |
| 341 | static int ext4_es_can_be_merged(struct extent_status *es1, |
| 342 | struct extent_status *es2) |
| 343 | { |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 344 | if (ext4_es_status(es1) != ext4_es_status(es2)) |
| 345 | return 0; |
| 346 | |
Zheng Liu | bd38436 | 2013-03-10 20:48:59 -0400 | [diff] [blame] | 347 | if (((__u64) es1->es_len) + es2->es_len > 0xFFFFFFFFULL) |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 348 | return 0; |
| 349 | |
Zheng Liu | bd38436 | 2013-03-10 20:48:59 -0400 | [diff] [blame] | 350 | if (((__u64) es1->es_lblk) + es1->es_len != es2->es_lblk) |
| 351 | return 0; |
| 352 | |
| 353 | if ((ext4_es_is_written(es1) || ext4_es_is_unwritten(es1)) && |
| 354 | (ext4_es_pblock(es1) + es1->es_len == ext4_es_pblock(es2))) |
| 355 | return 1; |
| 356 | |
| 357 | if (ext4_es_is_hole(es1)) |
| 358 | return 1; |
| 359 | |
| 360 | /* we need to check delayed extent is without unwritten status */ |
| 361 | if (ext4_es_is_delayed(es1) && !ext4_es_is_unwritten(es1)) |
| 362 | return 1; |
| 363 | |
| 364 | return 0; |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 365 | } |
| 366 | |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 367 | static struct extent_status * |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 368 | ext4_es_try_to_merge_left(struct inode *inode, struct extent_status *es) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 369 | { |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 370 | struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 371 | struct extent_status *es1; |
| 372 | struct rb_node *node; |
| 373 | |
| 374 | node = rb_prev(&es->rb_node); |
| 375 | if (!node) |
| 376 | return es; |
| 377 | |
| 378 | es1 = rb_entry(node, struct extent_status, rb_node); |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 379 | if (ext4_es_can_be_merged(es1, es)) { |
| 380 | es1->es_len += es->es_len; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 381 | rb_erase(&es->rb_node, &tree->root); |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 382 | ext4_es_free_extent(inode, es); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 383 | es = es1; |
| 384 | } |
| 385 | |
| 386 | return es; |
| 387 | } |
| 388 | |
| 389 | static struct extent_status * |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 390 | ext4_es_try_to_merge_right(struct inode *inode, struct extent_status *es) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 391 | { |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 392 | struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 393 | struct extent_status *es1; |
| 394 | struct rb_node *node; |
| 395 | |
| 396 | node = rb_next(&es->rb_node); |
| 397 | if (!node) |
| 398 | return es; |
| 399 | |
| 400 | es1 = rb_entry(node, struct extent_status, rb_node); |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 401 | if (ext4_es_can_be_merged(es, es1)) { |
| 402 | es->es_len += es1->es_len; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 403 | rb_erase(node, &tree->root); |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 404 | ext4_es_free_extent(inode, es1); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 405 | } |
| 406 | |
| 407 | return es; |
| 408 | } |
| 409 | |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 410 | #ifdef ES_AGGRESSIVE_TEST |
Zheng Liu | d7b2a00 | 2013-08-28 14:47:06 -0400 | [diff] [blame] | 411 | #include "ext4_extents.h" /* Needed when ES_AGGRESSIVE_TEST is defined */ |
| 412 | |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 413 | static void ext4_es_insert_extent_ext_check(struct inode *inode, |
| 414 | struct extent_status *es) |
| 415 | { |
| 416 | struct ext4_ext_path *path = NULL; |
| 417 | struct ext4_extent *ex; |
| 418 | ext4_lblk_t ee_block; |
| 419 | ext4_fsblk_t ee_start; |
| 420 | unsigned short ee_len; |
| 421 | int depth, ee_status, es_status; |
| 422 | |
Theodore Ts'o | 107a7bd | 2013-08-16 21:23:41 -0400 | [diff] [blame] | 423 | path = ext4_ext_find_extent(inode, es->es_lblk, NULL, EXT4_EX_NOCACHE); |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 424 | if (IS_ERR(path)) |
| 425 | return; |
| 426 | |
| 427 | depth = ext_depth(inode); |
| 428 | ex = path[depth].p_ext; |
| 429 | |
| 430 | if (ex) { |
| 431 | |
| 432 | ee_block = le32_to_cpu(ex->ee_block); |
| 433 | ee_start = ext4_ext_pblock(ex); |
| 434 | ee_len = ext4_ext_get_actual_len(ex); |
| 435 | |
| 436 | ee_status = ext4_ext_is_uninitialized(ex) ? 1 : 0; |
| 437 | es_status = ext4_es_is_unwritten(es) ? 1 : 0; |
| 438 | |
| 439 | /* |
| 440 | * Make sure ex and es are not overlap when we try to insert |
| 441 | * a delayed/hole extent. |
| 442 | */ |
| 443 | if (!ext4_es_is_written(es) && !ext4_es_is_unwritten(es)) { |
| 444 | if (in_range(es->es_lblk, ee_block, ee_len)) { |
Theodore Ts'o | bdafe42 | 2013-07-13 00:40:31 -0400 | [diff] [blame] | 445 | pr_warn("ES insert assertion failed for " |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 446 | "inode: %lu we can find an extent " |
| 447 | "at block [%d/%d/%llu/%c], but we " |
| 448 | "want to add an delayed/hole extent " |
| 449 | "[%d/%d/%llu/%llx]\n", |
| 450 | inode->i_ino, ee_block, ee_len, |
| 451 | ee_start, ee_status ? 'u' : 'w', |
| 452 | es->es_lblk, es->es_len, |
| 453 | ext4_es_pblock(es), ext4_es_status(es)); |
| 454 | } |
| 455 | goto out; |
| 456 | } |
| 457 | |
| 458 | /* |
| 459 | * We don't check ee_block == es->es_lblk, etc. because es |
| 460 | * might be a part of whole extent, vice versa. |
| 461 | */ |
| 462 | if (es->es_lblk < ee_block || |
| 463 | ext4_es_pblock(es) != ee_start + es->es_lblk - ee_block) { |
Theodore Ts'o | bdafe42 | 2013-07-13 00:40:31 -0400 | [diff] [blame] | 464 | pr_warn("ES insert assertion failed for inode: %lu " |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 465 | "ex_status [%d/%d/%llu/%c] != " |
| 466 | "es_status [%d/%d/%llu/%c]\n", inode->i_ino, |
| 467 | ee_block, ee_len, ee_start, |
| 468 | ee_status ? 'u' : 'w', es->es_lblk, es->es_len, |
| 469 | ext4_es_pblock(es), es_status ? 'u' : 'w'); |
| 470 | goto out; |
| 471 | } |
| 472 | |
| 473 | if (ee_status ^ es_status) { |
Theodore Ts'o | bdafe42 | 2013-07-13 00:40:31 -0400 | [diff] [blame] | 474 | pr_warn("ES insert assertion failed for inode: %lu " |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 475 | "ex_status [%d/%d/%llu/%c] != " |
| 476 | "es_status [%d/%d/%llu/%c]\n", inode->i_ino, |
| 477 | ee_block, ee_len, ee_start, |
| 478 | ee_status ? 'u' : 'w', es->es_lblk, es->es_len, |
| 479 | ext4_es_pblock(es), es_status ? 'u' : 'w'); |
| 480 | } |
| 481 | } else { |
| 482 | /* |
| 483 | * We can't find an extent on disk. So we need to make sure |
| 484 | * that we don't want to add an written/unwritten extent. |
| 485 | */ |
| 486 | if (!ext4_es_is_delayed(es) && !ext4_es_is_hole(es)) { |
Theodore Ts'o | bdafe42 | 2013-07-13 00:40:31 -0400 | [diff] [blame] | 487 | pr_warn("ES insert assertion failed for inode: %lu " |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 488 | "can't find an extent at block %d but we want " |
| 489 | "to add an written/unwritten extent " |
| 490 | "[%d/%d/%llu/%llx]\n", inode->i_ino, |
| 491 | es->es_lblk, es->es_lblk, es->es_len, |
| 492 | ext4_es_pblock(es), ext4_es_status(es)); |
| 493 | } |
| 494 | } |
| 495 | out: |
| 496 | if (path) { |
| 497 | ext4_ext_drop_refs(path); |
| 498 | kfree(path); |
| 499 | } |
| 500 | } |
| 501 | |
| 502 | static void ext4_es_insert_extent_ind_check(struct inode *inode, |
| 503 | struct extent_status *es) |
| 504 | { |
| 505 | struct ext4_map_blocks map; |
| 506 | int retval; |
| 507 | |
| 508 | /* |
| 509 | * Here we call ext4_ind_map_blocks to lookup a block mapping because |
| 510 | * 'Indirect' structure is defined in indirect.c. So we couldn't |
| 511 | * access direct/indirect tree from outside. It is too dirty to define |
| 512 | * this function in indirect.c file. |
| 513 | */ |
| 514 | |
| 515 | map.m_lblk = es->es_lblk; |
| 516 | map.m_len = es->es_len; |
| 517 | |
| 518 | retval = ext4_ind_map_blocks(NULL, inode, &map, 0); |
| 519 | if (retval > 0) { |
| 520 | if (ext4_es_is_delayed(es) || ext4_es_is_hole(es)) { |
| 521 | /* |
| 522 | * We want to add a delayed/hole extent but this |
| 523 | * block has been allocated. |
| 524 | */ |
Theodore Ts'o | bdafe42 | 2013-07-13 00:40:31 -0400 | [diff] [blame] | 525 | pr_warn("ES insert assertion failed for inode: %lu " |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 526 | "We can find blocks but we want to add a " |
| 527 | "delayed/hole extent [%d/%d/%llu/%llx]\n", |
| 528 | inode->i_ino, es->es_lblk, es->es_len, |
| 529 | ext4_es_pblock(es), ext4_es_status(es)); |
| 530 | return; |
| 531 | } else if (ext4_es_is_written(es)) { |
| 532 | if (retval != es->es_len) { |
Theodore Ts'o | bdafe42 | 2013-07-13 00:40:31 -0400 | [diff] [blame] | 533 | pr_warn("ES insert assertion failed for " |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 534 | "inode: %lu retval %d != es_len %d\n", |
| 535 | inode->i_ino, retval, es->es_len); |
| 536 | return; |
| 537 | } |
| 538 | if (map.m_pblk != ext4_es_pblock(es)) { |
Theodore Ts'o | bdafe42 | 2013-07-13 00:40:31 -0400 | [diff] [blame] | 539 | pr_warn("ES insert assertion failed for " |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 540 | "inode: %lu m_pblk %llu != " |
| 541 | "es_pblk %llu\n", |
| 542 | inode->i_ino, map.m_pblk, |
| 543 | ext4_es_pblock(es)); |
| 544 | return; |
| 545 | } |
| 546 | } else { |
| 547 | /* |
| 548 | * We don't need to check unwritten extent because |
| 549 | * indirect-based file doesn't have it. |
| 550 | */ |
| 551 | BUG_ON(1); |
| 552 | } |
| 553 | } else if (retval == 0) { |
| 554 | if (ext4_es_is_written(es)) { |
Theodore Ts'o | bdafe42 | 2013-07-13 00:40:31 -0400 | [diff] [blame] | 555 | pr_warn("ES insert assertion failed for inode: %lu " |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 556 | "We can't find the block but we want to add " |
| 557 | "an written extent [%d/%d/%llu/%llx]\n", |
| 558 | inode->i_ino, es->es_lblk, es->es_len, |
| 559 | ext4_es_pblock(es), ext4_es_status(es)); |
| 560 | return; |
| 561 | } |
| 562 | } |
| 563 | } |
| 564 | |
| 565 | static inline void ext4_es_insert_extent_check(struct inode *inode, |
| 566 | struct extent_status *es) |
| 567 | { |
| 568 | /* |
| 569 | * We don't need to worry about the race condition because |
| 570 | * caller takes i_data_sem locking. |
| 571 | */ |
| 572 | BUG_ON(!rwsem_is_locked(&EXT4_I(inode)->i_data_sem)); |
| 573 | if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) |
| 574 | ext4_es_insert_extent_ext_check(inode, es); |
| 575 | else |
| 576 | ext4_es_insert_extent_ind_check(inode, es); |
| 577 | } |
| 578 | #else |
| 579 | static inline void ext4_es_insert_extent_check(struct inode *inode, |
| 580 | struct extent_status *es) |
| 581 | { |
| 582 | } |
| 583 | #endif |
| 584 | |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 585 | static int __es_insert_extent(struct inode *inode, struct extent_status *newes) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 586 | { |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 587 | struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 588 | struct rb_node **p = &tree->root.rb_node; |
| 589 | struct rb_node *parent = NULL; |
| 590 | struct extent_status *es; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 591 | |
| 592 | while (*p) { |
| 593 | parent = *p; |
| 594 | es = rb_entry(parent, struct extent_status, rb_node); |
| 595 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 596 | if (newes->es_lblk < es->es_lblk) { |
| 597 | if (ext4_es_can_be_merged(newes, es)) { |
| 598 | /* |
| 599 | * Here we can modify es_lblk directly |
| 600 | * because it isn't overlapped. |
| 601 | */ |
| 602 | es->es_lblk = newes->es_lblk; |
| 603 | es->es_len += newes->es_len; |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 604 | if (ext4_es_is_written(es) || |
| 605 | ext4_es_is_unwritten(es)) |
| 606 | ext4_es_store_pblock(es, |
| 607 | newes->es_pblk); |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 608 | es = ext4_es_try_to_merge_left(inode, es); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 609 | goto out; |
| 610 | } |
| 611 | p = &(*p)->rb_left; |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 612 | } else if (newes->es_lblk > ext4_es_end(es)) { |
| 613 | if (ext4_es_can_be_merged(es, newes)) { |
| 614 | es->es_len += newes->es_len; |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 615 | es = ext4_es_try_to_merge_right(inode, es); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 616 | goto out; |
| 617 | } |
| 618 | p = &(*p)->rb_right; |
| 619 | } else { |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 620 | BUG_ON(1); |
| 621 | return -EINVAL; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 622 | } |
| 623 | } |
| 624 | |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 625 | es = ext4_es_alloc_extent(inode, newes->es_lblk, newes->es_len, |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 626 | newes->es_pblk); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 627 | if (!es) |
| 628 | return -ENOMEM; |
| 629 | rb_link_node(&es->rb_node, parent, p); |
| 630 | rb_insert_color(&es->rb_node, &tree->root); |
| 631 | |
| 632 | out: |
| 633 | tree->cache_es = es; |
| 634 | return 0; |
| 635 | } |
| 636 | |
| 637 | /* |
Theodore Ts'o | bdafe42 | 2013-07-13 00:40:31 -0400 | [diff] [blame] | 638 | * ext4_es_insert_extent() adds information to an inode's extent |
| 639 | * status tree. |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 640 | * |
| 641 | * Return 0 on success, error code on failure. |
| 642 | */ |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 643 | int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk, |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 644 | ext4_lblk_t len, ext4_fsblk_t pblk, |
Theodore Ts'o | 3be78c7 | 2013-08-16 21:22:41 -0400 | [diff] [blame] | 645 | unsigned int status) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 646 | { |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 647 | struct extent_status newes; |
| 648 | ext4_lblk_t end = lblk + len - 1; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 649 | int err = 0; |
| 650 | |
Theodore Ts'o | 3be78c7 | 2013-08-16 21:22:41 -0400 | [diff] [blame] | 651 | es_debug("add [%u/%u) %llu %x to extent status tree of inode %lu\n", |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 652 | lblk, len, pblk, status, inode->i_ino); |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 653 | |
Eryu Guan | d438147 | 2013-02-22 15:27:47 -0500 | [diff] [blame] | 654 | if (!len) |
| 655 | return 0; |
| 656 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 657 | BUG_ON(end < lblk); |
| 658 | |
| 659 | newes.es_lblk = lblk; |
| 660 | newes.es_len = len; |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 661 | ext4_es_store_pblock(&newes, pblk); |
| 662 | ext4_es_store_status(&newes, status); |
| 663 | trace_ext4_es_insert_extent(inode, &newes); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 664 | |
Dmitry Monakhov | 921f266 | 2013-03-10 21:01:03 -0400 | [diff] [blame] | 665 | ext4_es_insert_extent_check(inode, &newes); |
| 666 | |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 667 | write_lock(&EXT4_I(inode)->i_es_lock); |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 668 | err = __es_remove_extent(inode, lblk, end); |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 669 | if (err != 0) |
| 670 | goto error; |
Theodore Ts'o | e15f742 | 2013-07-15 00:12:14 -0400 | [diff] [blame] | 671 | retry: |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 672 | err = __es_insert_extent(inode, &newes); |
Theodore Ts'o | e15f742 | 2013-07-15 00:12:14 -0400 | [diff] [blame] | 673 | if (err == -ENOMEM && __ext4_es_shrink(EXT4_SB(inode->i_sb), 1, |
| 674 | EXT4_I(inode))) |
| 675 | goto retry; |
| 676 | if (err == -ENOMEM && !ext4_es_is_delayed(&newes)) |
| 677 | err = 0; |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 678 | |
| 679 | error: |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 680 | write_unlock(&EXT4_I(inode)->i_es_lock); |
| 681 | |
| 682 | ext4_es_print_tree(inode); |
| 683 | |
| 684 | return err; |
| 685 | } |
| 686 | |
Zheng Liu | d100eef | 2013-02-18 00:29:59 -0500 | [diff] [blame] | 687 | /* |
Theodore Ts'o | 107a7bd | 2013-08-16 21:23:41 -0400 | [diff] [blame] | 688 | * ext4_es_cache_extent() inserts information into the extent status |
| 689 | * tree if and only if there isn't information about the range in |
| 690 | * question already. |
| 691 | */ |
| 692 | void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk, |
| 693 | ext4_lblk_t len, ext4_fsblk_t pblk, |
| 694 | unsigned int status) |
| 695 | { |
| 696 | struct extent_status *es; |
| 697 | struct extent_status newes; |
| 698 | ext4_lblk_t end = lblk + len - 1; |
| 699 | |
| 700 | newes.es_lblk = lblk; |
| 701 | newes.es_len = len; |
| 702 | ext4_es_store_pblock(&newes, pblk); |
| 703 | ext4_es_store_status(&newes, status); |
| 704 | trace_ext4_es_cache_extent(inode, &newes); |
| 705 | |
| 706 | if (!len) |
| 707 | return; |
| 708 | |
| 709 | BUG_ON(end < lblk); |
| 710 | |
| 711 | write_lock(&EXT4_I(inode)->i_es_lock); |
| 712 | |
| 713 | es = __es_tree_search(&EXT4_I(inode)->i_es_tree.root, lblk); |
Theodore Ts'o | 7869a4a | 2013-08-16 22:05:14 -0400 | [diff] [blame] | 714 | if (!es || es->es_lblk > end) |
| 715 | __es_insert_extent(inode, &newes); |
Theodore Ts'o | 107a7bd | 2013-08-16 21:23:41 -0400 | [diff] [blame] | 716 | write_unlock(&EXT4_I(inode)->i_es_lock); |
| 717 | } |
| 718 | |
| 719 | /* |
Zheng Liu | d100eef | 2013-02-18 00:29:59 -0500 | [diff] [blame] | 720 | * ext4_es_lookup_extent() looks up an extent in extent status tree. |
| 721 | * |
| 722 | * ext4_es_lookup_extent is called by ext4_map_blocks/ext4_da_map_blocks. |
| 723 | * |
| 724 | * Return: 1 on found, 0 on not |
| 725 | */ |
| 726 | int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk, |
| 727 | struct extent_status *es) |
| 728 | { |
| 729 | struct ext4_es_tree *tree; |
| 730 | struct extent_status *es1 = NULL; |
| 731 | struct rb_node *node; |
| 732 | int found = 0; |
| 733 | |
| 734 | trace_ext4_es_lookup_extent_enter(inode, lblk); |
| 735 | es_debug("lookup extent in block %u\n", lblk); |
| 736 | |
| 737 | tree = &EXT4_I(inode)->i_es_tree; |
| 738 | read_lock(&EXT4_I(inode)->i_es_lock); |
| 739 | |
| 740 | /* find extent in cache firstly */ |
| 741 | es->es_lblk = es->es_len = es->es_pblk = 0; |
| 742 | if (tree->cache_es) { |
| 743 | es1 = tree->cache_es; |
| 744 | if (in_range(lblk, es1->es_lblk, es1->es_len)) { |
| 745 | es_debug("%u cached by [%u/%u)\n", |
| 746 | lblk, es1->es_lblk, es1->es_len); |
| 747 | found = 1; |
| 748 | goto out; |
| 749 | } |
| 750 | } |
| 751 | |
| 752 | node = tree->root.rb_node; |
| 753 | while (node) { |
| 754 | es1 = rb_entry(node, struct extent_status, rb_node); |
| 755 | if (lblk < es1->es_lblk) |
| 756 | node = node->rb_left; |
| 757 | else if (lblk > ext4_es_end(es1)) |
| 758 | node = node->rb_right; |
| 759 | else { |
| 760 | found = 1; |
| 761 | break; |
| 762 | } |
| 763 | } |
| 764 | |
| 765 | out: |
| 766 | if (found) { |
| 767 | BUG_ON(!es1); |
| 768 | es->es_lblk = es1->es_lblk; |
| 769 | es->es_len = es1->es_len; |
| 770 | es->es_pblk = es1->es_pblk; |
| 771 | } |
| 772 | |
| 773 | read_unlock(&EXT4_I(inode)->i_es_lock); |
| 774 | |
| 775 | trace_ext4_es_lookup_extent_exit(inode, es, found); |
| 776 | return found; |
| 777 | } |
| 778 | |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 779 | static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk, |
| 780 | ext4_lblk_t end) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 781 | { |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 782 | struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 783 | struct rb_node *node; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 784 | struct extent_status *es; |
| 785 | struct extent_status orig_es; |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 786 | ext4_lblk_t len1, len2; |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 787 | ext4_fsblk_t block; |
Theodore Ts'o | e15f742 | 2013-07-15 00:12:14 -0400 | [diff] [blame] | 788 | int err; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 789 | |
Theodore Ts'o | e15f742 | 2013-07-15 00:12:14 -0400 | [diff] [blame] | 790 | retry: |
| 791 | err = 0; |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 792 | es = __es_tree_search(&tree->root, lblk); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 793 | if (!es) |
| 794 | goto out; |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 795 | if (es->es_lblk > end) |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 796 | goto out; |
| 797 | |
| 798 | /* Simply invalidate cache_es. */ |
| 799 | tree->cache_es = NULL; |
| 800 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 801 | orig_es.es_lblk = es->es_lblk; |
| 802 | orig_es.es_len = es->es_len; |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 803 | orig_es.es_pblk = es->es_pblk; |
| 804 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 805 | len1 = lblk > es->es_lblk ? lblk - es->es_lblk : 0; |
| 806 | len2 = ext4_es_end(es) > end ? ext4_es_end(es) - end : 0; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 807 | if (len1 > 0) |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 808 | es->es_len = len1; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 809 | if (len2 > 0) { |
| 810 | if (len1 > 0) { |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 811 | struct extent_status newes; |
| 812 | |
| 813 | newes.es_lblk = end + 1; |
| 814 | newes.es_len = len2; |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 815 | if (ext4_es_is_written(&orig_es) || |
| 816 | ext4_es_is_unwritten(&orig_es)) { |
| 817 | block = ext4_es_pblock(&orig_es) + |
| 818 | orig_es.es_len - len2; |
| 819 | ext4_es_store_pblock(&newes, block); |
| 820 | } |
| 821 | ext4_es_store_status(&newes, ext4_es_status(&orig_es)); |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 822 | err = __es_insert_extent(inode, &newes); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 823 | if (err) { |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 824 | es->es_lblk = orig_es.es_lblk; |
| 825 | es->es_len = orig_es.es_len; |
Theodore Ts'o | e15f742 | 2013-07-15 00:12:14 -0400 | [diff] [blame] | 826 | if ((err == -ENOMEM) && |
| 827 | __ext4_es_shrink(EXT4_SB(inode->i_sb), 1, |
| 828 | EXT4_I(inode))) |
| 829 | goto retry; |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 830 | goto out; |
| 831 | } |
| 832 | } else { |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 833 | es->es_lblk = end + 1; |
| 834 | es->es_len = len2; |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 835 | if (ext4_es_is_written(es) || |
| 836 | ext4_es_is_unwritten(es)) { |
| 837 | block = orig_es.es_pblk + orig_es.es_len - len2; |
| 838 | ext4_es_store_pblock(es, block); |
| 839 | } |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 840 | } |
| 841 | goto out; |
| 842 | } |
| 843 | |
| 844 | if (len1 > 0) { |
| 845 | node = rb_next(&es->rb_node); |
| 846 | if (node) |
| 847 | es = rb_entry(node, struct extent_status, rb_node); |
| 848 | else |
| 849 | es = NULL; |
| 850 | } |
| 851 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 852 | while (es && ext4_es_end(es) <= end) { |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 853 | node = rb_next(&es->rb_node); |
| 854 | rb_erase(&es->rb_node, &tree->root); |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 855 | ext4_es_free_extent(inode, es); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 856 | if (!node) { |
| 857 | es = NULL; |
| 858 | break; |
| 859 | } |
| 860 | es = rb_entry(node, struct extent_status, rb_node); |
| 861 | } |
| 862 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 863 | if (es && es->es_lblk < end + 1) { |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 864 | ext4_lblk_t orig_len = es->es_len; |
| 865 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 866 | len1 = ext4_es_end(es) - end; |
| 867 | es->es_lblk = end + 1; |
| 868 | es->es_len = len1; |
Zheng Liu | fdc0212 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 869 | if (ext4_es_is_written(es) || ext4_es_is_unwritten(es)) { |
| 870 | block = es->es_pblk + orig_len - len1; |
| 871 | ext4_es_store_pblock(es, block); |
| 872 | } |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 873 | } |
| 874 | |
| 875 | out: |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 876 | return err; |
| 877 | } |
| 878 | |
| 879 | /* |
| 880 | * ext4_es_remove_extent() removes a space from a extent status tree. |
| 881 | * |
| 882 | * Return 0 on success, error code on failure. |
| 883 | */ |
| 884 | int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk, |
| 885 | ext4_lblk_t len) |
| 886 | { |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 887 | ext4_lblk_t end; |
| 888 | int err = 0; |
| 889 | |
| 890 | trace_ext4_es_remove_extent(inode, lblk, len); |
| 891 | es_debug("remove [%u/%u) from extent status tree of inode %lu\n", |
| 892 | lblk, len, inode->i_ino); |
| 893 | |
Eryu Guan | d438147 | 2013-02-22 15:27:47 -0500 | [diff] [blame] | 894 | if (!len) |
| 895 | return err; |
| 896 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 897 | end = lblk + len - 1; |
| 898 | BUG_ON(end < lblk); |
| 899 | |
Zheng Liu | 06b0c88 | 2013-02-18 00:26:51 -0500 | [diff] [blame] | 900 | write_lock(&EXT4_I(inode)->i_es_lock); |
Zheng Liu | bdedbb7 | 2013-02-18 00:32:02 -0500 | [diff] [blame] | 901 | err = __es_remove_extent(inode, lblk, end); |
Zheng Liu | 654598b | 2012-11-08 21:57:20 -0500 | [diff] [blame] | 902 | write_unlock(&EXT4_I(inode)->i_es_lock); |
| 903 | ext4_es_print_tree(inode); |
| 904 | return err; |
| 905 | } |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 906 | |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 907 | static int ext4_inode_touch_time_cmp(void *priv, struct list_head *a, |
| 908 | struct list_head *b) |
| 909 | { |
| 910 | struct ext4_inode_info *eia, *eib; |
| 911 | eia = list_entry(a, struct ext4_inode_info, i_es_lru); |
| 912 | eib = list_entry(b, struct ext4_inode_info, i_es_lru); |
| 913 | |
Theodore Ts'o | 7869a4a | 2013-08-16 22:05:14 -0400 | [diff] [blame] | 914 | if (ext4_test_inode_state(&eia->vfs_inode, EXT4_STATE_EXT_PRECACHED) && |
| 915 | !ext4_test_inode_state(&eib->vfs_inode, EXT4_STATE_EXT_PRECACHED)) |
| 916 | return 1; |
| 917 | if (!ext4_test_inode_state(&eia->vfs_inode, EXT4_STATE_EXT_PRECACHED) && |
| 918 | ext4_test_inode_state(&eib->vfs_inode, EXT4_STATE_EXT_PRECACHED)) |
| 919 | return -1; |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 920 | if (eia->i_touch_when == eib->i_touch_when) |
| 921 | return 0; |
| 922 | if (time_after(eia->i_touch_when, eib->i_touch_when)) |
| 923 | return 1; |
| 924 | else |
| 925 | return -1; |
| 926 | } |
| 927 | |
Theodore Ts'o | e15f742 | 2013-07-15 00:12:14 -0400 | [diff] [blame] | 928 | static int __ext4_es_shrink(struct ext4_sb_info *sbi, int nr_to_scan, |
| 929 | struct ext4_inode_info *locked_ei) |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 930 | { |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 931 | struct ext4_inode_info *ei; |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 932 | struct list_head *cur, *tmp; |
Theodore Ts'o | 7869a4a | 2013-08-16 22:05:14 -0400 | [diff] [blame] | 933 | LIST_HEAD(skipped); |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 934 | int ret, nr_shrunk = 0; |
Theodore Ts'o | 7869a4a | 2013-08-16 22:05:14 -0400 | [diff] [blame] | 935 | int retried = 0, skip_precached = 1, nr_skipped = 0; |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 936 | |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 937 | spin_lock(&sbi->s_es_lru_lock); |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 938 | |
Theodore Ts'o | 7869a4a | 2013-08-16 22:05:14 -0400 | [diff] [blame] | 939 | retry: |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 940 | list_for_each_safe(cur, tmp, &sbi->s_es_lru) { |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 941 | /* |
| 942 | * If we have already reclaimed all extents from extent |
| 943 | * status tree, just stop the loop immediately. |
| 944 | */ |
| 945 | if (percpu_counter_read_positive(&sbi->s_extent_cache_cnt) == 0) |
| 946 | break; |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 947 | |
| 948 | ei = list_entry(cur, struct ext4_inode_info, i_es_lru); |
| 949 | |
Theodore Ts'o | 7869a4a | 2013-08-16 22:05:14 -0400 | [diff] [blame] | 950 | /* |
| 951 | * Skip the inode that is newer than the last_sorted |
| 952 | * time. Normally we try hard to avoid shrinking |
| 953 | * precached inodes, but we will as a last resort. |
| 954 | */ |
| 955 | if ((sbi->s_es_last_sorted < ei->i_touch_when) || |
| 956 | (skip_precached && ext4_test_inode_state(&ei->vfs_inode, |
| 957 | EXT4_STATE_EXT_PRECACHED))) { |
| 958 | nr_skipped++; |
| 959 | list_move_tail(cur, &skipped); |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 960 | continue; |
| 961 | } |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 962 | |
Theodore Ts'o | e15f742 | 2013-07-15 00:12:14 -0400 | [diff] [blame] | 963 | if (ei->i_es_lru_nr == 0 || ei == locked_ei) |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 964 | continue; |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 965 | |
| 966 | write_lock(&ei->i_es_lock); |
| 967 | ret = __es_try_to_reclaim_extents(ei, nr_to_scan); |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 968 | if (ei->i_es_lru_nr == 0) |
| 969 | list_del_init(&ei->i_es_lru); |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 970 | write_unlock(&ei->i_es_lock); |
| 971 | |
| 972 | nr_shrunk += ret; |
| 973 | nr_to_scan -= ret; |
| 974 | if (nr_to_scan == 0) |
| 975 | break; |
| 976 | } |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 977 | |
| 978 | /* Move the newer inodes into the tail of the LRU list. */ |
Theodore Ts'o | 7869a4a | 2013-08-16 22:05:14 -0400 | [diff] [blame] | 979 | list_splice_tail(&skipped, &sbi->s_es_lru); |
| 980 | INIT_LIST_HEAD(&skipped); |
| 981 | |
| 982 | /* |
| 983 | * If we skipped any inodes, and we weren't able to make any |
| 984 | * forward progress, sort the list and try again. |
| 985 | */ |
| 986 | if ((nr_shrunk == 0) && nr_skipped && !retried) { |
| 987 | retried++; |
| 988 | list_sort(NULL, &sbi->s_es_lru, ext4_inode_touch_time_cmp); |
| 989 | sbi->s_es_last_sorted = jiffies; |
| 990 | ei = list_first_entry(&sbi->s_es_lru, struct ext4_inode_info, |
| 991 | i_es_lru); |
| 992 | /* |
| 993 | * If there are no non-precached inodes left on the |
| 994 | * list, start releasing precached extents. |
| 995 | */ |
| 996 | if (ext4_test_inode_state(&ei->vfs_inode, |
| 997 | EXT4_STATE_EXT_PRECACHED)) |
| 998 | skip_precached = 0; |
| 999 | goto retry; |
| 1000 | } |
| 1001 | |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1002 | spin_unlock(&sbi->s_es_lru_lock); |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1003 | |
Theodore Ts'o | e15f742 | 2013-07-15 00:12:14 -0400 | [diff] [blame] | 1004 | if (locked_ei && nr_shrunk == 0) |
Theodore Ts'o | 7869a4a | 2013-08-16 22:05:14 -0400 | [diff] [blame] | 1005 | nr_shrunk = __es_try_to_reclaim_extents(locked_ei, nr_to_scan); |
Theodore Ts'o | e15f742 | 2013-07-15 00:12:14 -0400 | [diff] [blame] | 1006 | |
| 1007 | return nr_shrunk; |
| 1008 | } |
| 1009 | |
| 1010 | static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc) |
| 1011 | { |
| 1012 | struct ext4_sb_info *sbi = container_of(shrink, |
| 1013 | struct ext4_sb_info, s_es_shrinker); |
| 1014 | int nr_to_scan = sc->nr_to_scan; |
| 1015 | int ret, nr_shrunk; |
| 1016 | |
| 1017 | ret = percpu_counter_read_positive(&sbi->s_extent_cache_cnt); |
| 1018 | trace_ext4_es_shrink_enter(sbi->s_sb, nr_to_scan, ret); |
| 1019 | |
| 1020 | if (!nr_to_scan) |
| 1021 | return ret; |
| 1022 | |
| 1023 | nr_shrunk = __ext4_es_shrink(sbi, nr_to_scan, NULL); |
| 1024 | |
Theodore Ts'o | 1ac6466 | 2013-03-02 10:27:46 -0500 | [diff] [blame] | 1025 | ret = percpu_counter_read_positive(&sbi->s_extent_cache_cnt); |
Theodore Ts'o | 2463077 | 2013-02-28 23:58:56 -0500 | [diff] [blame] | 1026 | trace_ext4_es_shrink_exit(sbi->s_sb, nr_shrunk, ret); |
| 1027 | return ret; |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1028 | } |
| 1029 | |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 1030 | void ext4_es_register_shrinker(struct ext4_sb_info *sbi) |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1031 | { |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1032 | INIT_LIST_HEAD(&sbi->s_es_lru); |
| 1033 | spin_lock_init(&sbi->s_es_lru_lock); |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 1034 | sbi->s_es_last_sorted = 0; |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1035 | sbi->s_es_shrinker.shrink = ext4_es_shrink; |
| 1036 | sbi->s_es_shrinker.seeks = DEFAULT_SEEKS; |
| 1037 | register_shrinker(&sbi->s_es_shrinker); |
| 1038 | } |
| 1039 | |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 1040 | void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi) |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1041 | { |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 1042 | unregister_shrinker(&sbi->s_es_shrinker); |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1043 | } |
| 1044 | |
| 1045 | void ext4_es_lru_add(struct inode *inode) |
| 1046 | { |
| 1047 | struct ext4_inode_info *ei = EXT4_I(inode); |
| 1048 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 1049 | |
Zheng Liu | d3922a7 | 2013-07-01 08:12:37 -0400 | [diff] [blame] | 1050 | ei->i_touch_when = jiffies; |
| 1051 | |
| 1052 | if (!list_empty(&ei->i_es_lru)) |
| 1053 | return; |
| 1054 | |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1055 | spin_lock(&sbi->s_es_lru_lock); |
| 1056 | if (list_empty(&ei->i_es_lru)) |
| 1057 | list_add_tail(&ei->i_es_lru, &sbi->s_es_lru); |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1058 | spin_unlock(&sbi->s_es_lru_lock); |
| 1059 | } |
| 1060 | |
| 1061 | void ext4_es_lru_del(struct inode *inode) |
| 1062 | { |
| 1063 | struct ext4_inode_info *ei = EXT4_I(inode); |
| 1064 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 1065 | |
| 1066 | spin_lock(&sbi->s_es_lru_lock); |
| 1067 | if (!list_empty(&ei->i_es_lru)) |
| 1068 | list_del_init(&ei->i_es_lru); |
| 1069 | spin_unlock(&sbi->s_es_lru_lock); |
| 1070 | } |
| 1071 | |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1072 | static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei, |
| 1073 | int nr_to_scan) |
| 1074 | { |
| 1075 | struct inode *inode = &ei->vfs_inode; |
| 1076 | struct ext4_es_tree *tree = &ei->i_es_tree; |
| 1077 | struct rb_node *node; |
| 1078 | struct extent_status *es; |
| 1079 | int nr_shrunk = 0; |
Theodore Ts'o | 7869a4a | 2013-08-16 22:05:14 -0400 | [diff] [blame] | 1080 | static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL, |
| 1081 | DEFAULT_RATELIMIT_BURST); |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1082 | |
| 1083 | if (ei->i_es_lru_nr == 0) |
| 1084 | return 0; |
| 1085 | |
Theodore Ts'o | 7869a4a | 2013-08-16 22:05:14 -0400 | [diff] [blame] | 1086 | if (ext4_test_inode_state(inode, EXT4_STATE_EXT_PRECACHED) && |
| 1087 | __ratelimit(&_rs)) |
| 1088 | ext4_warning(inode->i_sb, "forced shrink of precached extents"); |
| 1089 | |
Zheng Liu | 74cd15c | 2013-02-18 00:32:55 -0500 | [diff] [blame] | 1090 | node = rb_first(&tree->root); |
| 1091 | while (node != NULL) { |
| 1092 | es = rb_entry(node, struct extent_status, rb_node); |
| 1093 | node = rb_next(&es->rb_node); |
| 1094 | /* |
| 1095 | * We can't reclaim delayed extent from status tree because |
| 1096 | * fiemap, bigallic, and seek_data/hole need to use it. |
| 1097 | */ |
| 1098 | if (!ext4_es_is_delayed(es)) { |
| 1099 | rb_erase(&es->rb_node, &tree->root); |
| 1100 | ext4_es_free_extent(inode, es); |
| 1101 | nr_shrunk++; |
| 1102 | if (--nr_to_scan == 0) |
| 1103 | break; |
| 1104 | } |
| 1105 | } |
| 1106 | tree->cache_es = NULL; |
| 1107 | return nr_shrunk; |
| 1108 | } |