Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1 | #include <linux/bitops.h> |
| 2 | #include <linux/slab.h> |
| 3 | #include <linux/bio.h> |
| 4 | #include <linux/mm.h> |
| 5 | #include <linux/gfp.h> |
| 6 | #include <linux/pagemap.h> |
| 7 | #include <linux/page-flags.h> |
| 8 | #include <linux/module.h> |
| 9 | #include <linux/spinlock.h> |
| 10 | #include <linux/blkdev.h> |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 11 | #include <linux/swap.h> |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 12 | #include <linux/version.h> |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 13 | #include "extent_map.h" |
| 14 | |
Chris Mason | 86479a0 | 2007-09-10 19:58:16 -0400 | [diff] [blame] | 15 | /* temporary define until extent_map moves out of btrfs */ |
| 16 | struct kmem_cache *btrfs_cache_create(const char *name, size_t size, |
| 17 | unsigned long extra_flags, |
| 18 | void (*ctor)(void *, struct kmem_cache *, |
| 19 | unsigned long)); |
| 20 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 21 | static struct kmem_cache *extent_map_cache; |
| 22 | static struct kmem_cache *extent_state_cache; |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 23 | static struct kmem_cache *extent_buffer_cache; |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 24 | |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 25 | static LIST_HEAD(buffers); |
| 26 | static LIST_HEAD(states); |
| 27 | |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 28 | static spinlock_t state_lock = SPIN_LOCK_UNLOCKED; |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 29 | #define BUFFER_LRU_MAX 64 |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 30 | |
| 31 | struct tree_entry { |
| 32 | u64 start; |
| 33 | u64 end; |
| 34 | int in_tree; |
| 35 | struct rb_node rb_node; |
| 36 | }; |
| 37 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 38 | void __init extent_map_init(void) |
| 39 | { |
Chris Mason | 86479a0 | 2007-09-10 19:58:16 -0400 | [diff] [blame] | 40 | extent_map_cache = btrfs_cache_create("extent_map", |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 41 | sizeof(struct extent_map), 0, |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 42 | NULL); |
Chris Mason | 86479a0 | 2007-09-10 19:58:16 -0400 | [diff] [blame] | 43 | extent_state_cache = btrfs_cache_create("extent_state", |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 44 | sizeof(struct extent_state), 0, |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 45 | NULL); |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 46 | extent_buffer_cache = btrfs_cache_create("extent_buffers", |
| 47 | sizeof(struct extent_buffer), 0, |
| 48 | NULL); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 49 | } |
| 50 | |
| 51 | void __exit extent_map_exit(void) |
| 52 | { |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 53 | struct extent_state *state; |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 54 | |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 55 | while (!list_empty(&states)) { |
| 56 | state = list_entry(states.next, struct extent_state, list); |
| 57 | printk("state leak: start %Lu end %Lu state %lu in tree %d refs %d\n", state->start, state->end, state->state, state->in_tree, atomic_read(&state->refs)); |
| 58 | list_del(&state->list); |
| 59 | kmem_cache_free(extent_state_cache, state); |
| 60 | |
| 61 | } |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 62 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 63 | if (extent_map_cache) |
| 64 | kmem_cache_destroy(extent_map_cache); |
| 65 | if (extent_state_cache) |
| 66 | kmem_cache_destroy(extent_state_cache); |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 67 | if (extent_buffer_cache) |
| 68 | kmem_cache_destroy(extent_buffer_cache); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 69 | } |
| 70 | |
| 71 | void extent_map_tree_init(struct extent_map_tree *tree, |
| 72 | struct address_space *mapping, gfp_t mask) |
| 73 | { |
| 74 | tree->map.rb_node = NULL; |
| 75 | tree->state.rb_node = NULL; |
Chris Mason | 07157aa | 2007-08-30 08:50:51 -0400 | [diff] [blame] | 76 | tree->ops = NULL; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 77 | rwlock_init(&tree->lock); |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 78 | spin_lock_init(&tree->lru_lock); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 79 | tree->mapping = mapping; |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 80 | INIT_LIST_HEAD(&tree->buffer_lru); |
| 81 | tree->lru_size = 0; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 82 | } |
| 83 | EXPORT_SYMBOL(extent_map_tree_init); |
| 84 | |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 85 | void extent_map_tree_empty_lru(struct extent_map_tree *tree) |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 86 | { |
| 87 | struct extent_buffer *eb; |
| 88 | while(!list_empty(&tree->buffer_lru)) { |
| 89 | eb = list_entry(tree->buffer_lru.next, struct extent_buffer, |
| 90 | lru); |
| 91 | list_del(&eb->lru); |
| 92 | free_extent_buffer(eb); |
| 93 | } |
| 94 | } |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 95 | EXPORT_SYMBOL(extent_map_tree_empty_lru); |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 96 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 97 | struct extent_map *alloc_extent_map(gfp_t mask) |
| 98 | { |
| 99 | struct extent_map *em; |
| 100 | em = kmem_cache_alloc(extent_map_cache, mask); |
| 101 | if (!em || IS_ERR(em)) |
| 102 | return em; |
| 103 | em->in_tree = 0; |
| 104 | atomic_set(&em->refs, 1); |
| 105 | return em; |
| 106 | } |
| 107 | EXPORT_SYMBOL(alloc_extent_map); |
| 108 | |
| 109 | void free_extent_map(struct extent_map *em) |
| 110 | { |
Chris Mason | 2bf5a72 | 2007-08-30 11:54:02 -0400 | [diff] [blame] | 111 | if (!em) |
| 112 | return; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 113 | if (atomic_dec_and_test(&em->refs)) { |
| 114 | WARN_ON(em->in_tree); |
| 115 | kmem_cache_free(extent_map_cache, em); |
| 116 | } |
| 117 | } |
| 118 | EXPORT_SYMBOL(free_extent_map); |
| 119 | |
| 120 | |
| 121 | struct extent_state *alloc_extent_state(gfp_t mask) |
| 122 | { |
| 123 | struct extent_state *state; |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 124 | unsigned long flags; |
| 125 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 126 | state = kmem_cache_alloc(extent_state_cache, mask); |
| 127 | if (!state || IS_ERR(state)) |
| 128 | return state; |
| 129 | state->state = 0; |
| 130 | state->in_tree = 0; |
Chris Mason | 07157aa | 2007-08-30 08:50:51 -0400 | [diff] [blame] | 131 | state->private = 0; |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 132 | |
| 133 | spin_lock_irqsave(&state_lock, flags); |
| 134 | list_add(&state->list, &states); |
| 135 | spin_unlock_irqrestore(&state_lock, flags); |
| 136 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 137 | atomic_set(&state->refs, 1); |
| 138 | init_waitqueue_head(&state->wq); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 139 | return state; |
| 140 | } |
| 141 | EXPORT_SYMBOL(alloc_extent_state); |
| 142 | |
| 143 | void free_extent_state(struct extent_state *state) |
| 144 | { |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 145 | unsigned long flags; |
Chris Mason | 2bf5a72 | 2007-08-30 11:54:02 -0400 | [diff] [blame] | 146 | if (!state) |
| 147 | return; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 148 | if (atomic_dec_and_test(&state->refs)) { |
| 149 | WARN_ON(state->in_tree); |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 150 | spin_lock_irqsave(&state_lock, flags); |
| 151 | list_del(&state->list); |
| 152 | spin_unlock_irqrestore(&state_lock, flags); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 153 | kmem_cache_free(extent_state_cache, state); |
| 154 | } |
| 155 | } |
| 156 | EXPORT_SYMBOL(free_extent_state); |
| 157 | |
| 158 | static struct rb_node *tree_insert(struct rb_root *root, u64 offset, |
| 159 | struct rb_node *node) |
| 160 | { |
| 161 | struct rb_node ** p = &root->rb_node; |
| 162 | struct rb_node * parent = NULL; |
| 163 | struct tree_entry *entry; |
| 164 | |
| 165 | while(*p) { |
| 166 | parent = *p; |
| 167 | entry = rb_entry(parent, struct tree_entry, rb_node); |
| 168 | |
| 169 | if (offset < entry->start) |
| 170 | p = &(*p)->rb_left; |
| 171 | else if (offset > entry->end) |
| 172 | p = &(*p)->rb_right; |
| 173 | else |
| 174 | return parent; |
| 175 | } |
| 176 | |
| 177 | entry = rb_entry(node, struct tree_entry, rb_node); |
| 178 | entry->in_tree = 1; |
| 179 | rb_link_node(node, parent, p); |
| 180 | rb_insert_color(node, root); |
| 181 | return NULL; |
| 182 | } |
| 183 | |
| 184 | static struct rb_node *__tree_search(struct rb_root *root, u64 offset, |
| 185 | struct rb_node **prev_ret) |
| 186 | { |
| 187 | struct rb_node * n = root->rb_node; |
| 188 | struct rb_node *prev = NULL; |
| 189 | struct tree_entry *entry; |
| 190 | struct tree_entry *prev_entry = NULL; |
| 191 | |
| 192 | while(n) { |
| 193 | entry = rb_entry(n, struct tree_entry, rb_node); |
| 194 | prev = n; |
| 195 | prev_entry = entry; |
| 196 | |
| 197 | if (offset < entry->start) |
| 198 | n = n->rb_left; |
| 199 | else if (offset > entry->end) |
| 200 | n = n->rb_right; |
| 201 | else |
| 202 | return n; |
| 203 | } |
| 204 | if (!prev_ret) |
| 205 | return NULL; |
| 206 | while(prev && offset > prev_entry->end) { |
| 207 | prev = rb_next(prev); |
| 208 | prev_entry = rb_entry(prev, struct tree_entry, rb_node); |
| 209 | } |
| 210 | *prev_ret = prev; |
| 211 | return NULL; |
| 212 | } |
| 213 | |
| 214 | static inline struct rb_node *tree_search(struct rb_root *root, u64 offset) |
| 215 | { |
| 216 | struct rb_node *prev; |
| 217 | struct rb_node *ret; |
| 218 | ret = __tree_search(root, offset, &prev); |
| 219 | if (!ret) |
| 220 | return prev; |
| 221 | return ret; |
| 222 | } |
| 223 | |
| 224 | static int tree_delete(struct rb_root *root, u64 offset) |
| 225 | { |
| 226 | struct rb_node *node; |
| 227 | struct tree_entry *entry; |
| 228 | |
| 229 | node = __tree_search(root, offset, NULL); |
| 230 | if (!node) |
| 231 | return -ENOENT; |
| 232 | entry = rb_entry(node, struct tree_entry, rb_node); |
| 233 | entry->in_tree = 0; |
| 234 | rb_erase(node, root); |
| 235 | return 0; |
| 236 | } |
| 237 | |
| 238 | /* |
| 239 | * add_extent_mapping tries a simple backward merge with existing |
| 240 | * mappings. The extent_map struct passed in will be inserted into |
| 241 | * the tree directly (no copies made, just a reference taken). |
| 242 | */ |
| 243 | int add_extent_mapping(struct extent_map_tree *tree, |
| 244 | struct extent_map *em) |
| 245 | { |
| 246 | int ret = 0; |
| 247 | struct extent_map *prev = NULL; |
| 248 | struct rb_node *rb; |
| 249 | |
| 250 | write_lock_irq(&tree->lock); |
| 251 | rb = tree_insert(&tree->map, em->end, &em->rb_node); |
| 252 | if (rb) { |
| 253 | prev = rb_entry(rb, struct extent_map, rb_node); |
| 254 | printk("found extent map %Lu %Lu on insert of %Lu %Lu\n", prev->start, prev->end, em->start, em->end); |
| 255 | ret = -EEXIST; |
| 256 | goto out; |
| 257 | } |
| 258 | atomic_inc(&em->refs); |
| 259 | if (em->start != 0) { |
| 260 | rb = rb_prev(&em->rb_node); |
| 261 | if (rb) |
| 262 | prev = rb_entry(rb, struct extent_map, rb_node); |
| 263 | if (prev && prev->end + 1 == em->start && |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 264 | ((em->block_start == EXTENT_MAP_HOLE && |
| 265 | prev->block_start == EXTENT_MAP_HOLE) || |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 266 | (em->block_start == prev->block_end + 1))) { |
| 267 | em->start = prev->start; |
| 268 | em->block_start = prev->block_start; |
| 269 | rb_erase(&prev->rb_node, &tree->map); |
| 270 | prev->in_tree = 0; |
| 271 | free_extent_map(prev); |
| 272 | } |
| 273 | } |
| 274 | out: |
| 275 | write_unlock_irq(&tree->lock); |
| 276 | return ret; |
| 277 | } |
| 278 | EXPORT_SYMBOL(add_extent_mapping); |
| 279 | |
| 280 | /* |
| 281 | * lookup_extent_mapping returns the first extent_map struct in the |
| 282 | * tree that intersects the [start, end] (inclusive) range. There may |
| 283 | * be additional objects in the tree that intersect, so check the object |
| 284 | * returned carefully to make sure you don't need additional lookups. |
| 285 | */ |
| 286 | struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, |
| 287 | u64 start, u64 end) |
| 288 | { |
| 289 | struct extent_map *em; |
| 290 | struct rb_node *rb_node; |
| 291 | |
| 292 | read_lock_irq(&tree->lock); |
| 293 | rb_node = tree_search(&tree->map, start); |
| 294 | if (!rb_node) { |
| 295 | em = NULL; |
| 296 | goto out; |
| 297 | } |
| 298 | if (IS_ERR(rb_node)) { |
| 299 | em = ERR_PTR(PTR_ERR(rb_node)); |
| 300 | goto out; |
| 301 | } |
| 302 | em = rb_entry(rb_node, struct extent_map, rb_node); |
| 303 | if (em->end < start || em->start > end) { |
| 304 | em = NULL; |
| 305 | goto out; |
| 306 | } |
| 307 | atomic_inc(&em->refs); |
| 308 | out: |
| 309 | read_unlock_irq(&tree->lock); |
| 310 | return em; |
| 311 | } |
| 312 | EXPORT_SYMBOL(lookup_extent_mapping); |
| 313 | |
| 314 | /* |
| 315 | * removes an extent_map struct from the tree. No reference counts are |
| 316 | * dropped, and no checks are done to see if the range is in use |
| 317 | */ |
| 318 | int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em) |
| 319 | { |
| 320 | int ret; |
| 321 | |
| 322 | write_lock_irq(&tree->lock); |
| 323 | ret = tree_delete(&tree->map, em->end); |
| 324 | write_unlock_irq(&tree->lock); |
| 325 | return ret; |
| 326 | } |
| 327 | EXPORT_SYMBOL(remove_extent_mapping); |
| 328 | |
| 329 | /* |
| 330 | * utility function to look for merge candidates inside a given range. |
| 331 | * Any extents with matching state are merged together into a single |
| 332 | * extent in the tree. Extents with EXTENT_IO in their state field |
| 333 | * are not merged because the end_io handlers need to be able to do |
| 334 | * operations on them without sleeping (or doing allocations/splits). |
| 335 | * |
| 336 | * This should be called with the tree lock held. |
| 337 | */ |
| 338 | static int merge_state(struct extent_map_tree *tree, |
| 339 | struct extent_state *state) |
| 340 | { |
| 341 | struct extent_state *other; |
| 342 | struct rb_node *other_node; |
| 343 | |
| 344 | if (state->state & EXTENT_IOBITS) |
| 345 | return 0; |
| 346 | |
| 347 | other_node = rb_prev(&state->rb_node); |
| 348 | if (other_node) { |
| 349 | other = rb_entry(other_node, struct extent_state, rb_node); |
| 350 | if (other->end == state->start - 1 && |
| 351 | other->state == state->state) { |
| 352 | state->start = other->start; |
| 353 | other->in_tree = 0; |
| 354 | rb_erase(&other->rb_node, &tree->state); |
| 355 | free_extent_state(other); |
| 356 | } |
| 357 | } |
| 358 | other_node = rb_next(&state->rb_node); |
| 359 | if (other_node) { |
| 360 | other = rb_entry(other_node, struct extent_state, rb_node); |
| 361 | if (other->start == state->end + 1 && |
| 362 | other->state == state->state) { |
| 363 | other->start = state->start; |
| 364 | state->in_tree = 0; |
| 365 | rb_erase(&state->rb_node, &tree->state); |
| 366 | free_extent_state(state); |
| 367 | } |
| 368 | } |
| 369 | return 0; |
| 370 | } |
| 371 | |
| 372 | /* |
| 373 | * insert an extent_state struct into the tree. 'bits' are set on the |
| 374 | * struct before it is inserted. |
| 375 | * |
| 376 | * This may return -EEXIST if the extent is already there, in which case the |
| 377 | * state struct is freed. |
| 378 | * |
| 379 | * The tree lock is not taken internally. This is a utility function and |
| 380 | * probably isn't what you want to call (see set/clear_extent_bit). |
| 381 | */ |
| 382 | static int insert_state(struct extent_map_tree *tree, |
| 383 | struct extent_state *state, u64 start, u64 end, |
| 384 | int bits) |
| 385 | { |
| 386 | struct rb_node *node; |
| 387 | |
| 388 | if (end < start) { |
| 389 | printk("end < start %Lu %Lu\n", end, start); |
| 390 | WARN_ON(1); |
| 391 | } |
| 392 | state->state |= bits; |
| 393 | state->start = start; |
| 394 | state->end = end; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 395 | node = tree_insert(&tree->state, end, &state->rb_node); |
| 396 | if (node) { |
| 397 | struct extent_state *found; |
| 398 | found = rb_entry(node, struct extent_state, rb_node); |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 399 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, start, end); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 400 | free_extent_state(state); |
| 401 | return -EEXIST; |
| 402 | } |
| 403 | merge_state(tree, state); |
| 404 | return 0; |
| 405 | } |
| 406 | |
| 407 | /* |
| 408 | * split a given extent state struct in two, inserting the preallocated |
| 409 | * struct 'prealloc' as the newly created second half. 'split' indicates an |
| 410 | * offset inside 'orig' where it should be split. |
| 411 | * |
| 412 | * Before calling, |
| 413 | * the tree has 'orig' at [orig->start, orig->end]. After calling, there |
| 414 | * are two extent state structs in the tree: |
| 415 | * prealloc: [orig->start, split - 1] |
| 416 | * orig: [ split, orig->end ] |
| 417 | * |
| 418 | * The tree locks are not taken by this function. They need to be held |
| 419 | * by the caller. |
| 420 | */ |
| 421 | static int split_state(struct extent_map_tree *tree, struct extent_state *orig, |
| 422 | struct extent_state *prealloc, u64 split) |
| 423 | { |
| 424 | struct rb_node *node; |
| 425 | prealloc->start = orig->start; |
| 426 | prealloc->end = split - 1; |
| 427 | prealloc->state = orig->state; |
| 428 | orig->start = split; |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 429 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 430 | node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); |
| 431 | if (node) { |
| 432 | struct extent_state *found; |
| 433 | found = rb_entry(node, struct extent_state, rb_node); |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 434 | printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, prealloc->start, prealloc->end); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 435 | free_extent_state(prealloc); |
| 436 | return -EEXIST; |
| 437 | } |
| 438 | return 0; |
| 439 | } |
| 440 | |
| 441 | /* |
| 442 | * utility function to clear some bits in an extent state struct. |
| 443 | * it will optionally wake up any one waiting on this state (wake == 1), or |
| 444 | * forcibly remove the state from the tree (delete == 1). |
| 445 | * |
| 446 | * If no bits are set on the state struct after clearing things, the |
| 447 | * struct is freed and removed from the tree |
| 448 | */ |
| 449 | static int clear_state_bit(struct extent_map_tree *tree, |
| 450 | struct extent_state *state, int bits, int wake, |
| 451 | int delete) |
| 452 | { |
| 453 | int ret = state->state & bits; |
| 454 | state->state &= ~bits; |
| 455 | if (wake) |
| 456 | wake_up(&state->wq); |
| 457 | if (delete || state->state == 0) { |
| 458 | if (state->in_tree) { |
| 459 | rb_erase(&state->rb_node, &tree->state); |
| 460 | state->in_tree = 0; |
| 461 | free_extent_state(state); |
| 462 | } else { |
| 463 | WARN_ON(1); |
| 464 | } |
| 465 | } else { |
| 466 | merge_state(tree, state); |
| 467 | } |
| 468 | return ret; |
| 469 | } |
| 470 | |
| 471 | /* |
| 472 | * clear some bits on a range in the tree. This may require splitting |
| 473 | * or inserting elements in the tree, so the gfp mask is used to |
| 474 | * indicate which allocations or sleeping are allowed. |
| 475 | * |
| 476 | * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove |
| 477 | * the given range from the tree regardless of state (ie for truncate). |
| 478 | * |
| 479 | * the range [start, end] is inclusive. |
| 480 | * |
| 481 | * This takes the tree lock, and returns < 0 on error, > 0 if any of the |
| 482 | * bits were already set, or zero if none of the bits were already set. |
| 483 | */ |
| 484 | int clear_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, |
| 485 | int bits, int wake, int delete, gfp_t mask) |
| 486 | { |
| 487 | struct extent_state *state; |
| 488 | struct extent_state *prealloc = NULL; |
| 489 | struct rb_node *node; |
Christoph Hellwig | 90f1c19 | 2007-09-10 20:02:27 -0400 | [diff] [blame] | 490 | unsigned long flags; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 491 | int err; |
| 492 | int set = 0; |
| 493 | |
| 494 | again: |
| 495 | if (!prealloc && (mask & __GFP_WAIT)) { |
| 496 | prealloc = alloc_extent_state(mask); |
| 497 | if (!prealloc) |
| 498 | return -ENOMEM; |
| 499 | } |
| 500 | |
Christoph Hellwig | 90f1c19 | 2007-09-10 20:02:27 -0400 | [diff] [blame] | 501 | write_lock_irqsave(&tree->lock, flags); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 502 | /* |
| 503 | * this search will find the extents that end after |
| 504 | * our range starts |
| 505 | */ |
| 506 | node = tree_search(&tree->state, start); |
| 507 | if (!node) |
| 508 | goto out; |
| 509 | state = rb_entry(node, struct extent_state, rb_node); |
| 510 | if (state->start > end) |
| 511 | goto out; |
| 512 | WARN_ON(state->end < start); |
| 513 | |
| 514 | /* |
| 515 | * | ---- desired range ---- | |
| 516 | * | state | or |
| 517 | * | ------------- state -------------- | |
| 518 | * |
| 519 | * We need to split the extent we found, and may flip |
| 520 | * bits on second half. |
| 521 | * |
| 522 | * If the extent we found extends past our range, we |
| 523 | * just split and search again. It'll get split again |
| 524 | * the next time though. |
| 525 | * |
| 526 | * If the extent we found is inside our range, we clear |
| 527 | * the desired bit on it. |
| 528 | */ |
| 529 | |
| 530 | if (state->start < start) { |
| 531 | err = split_state(tree, state, prealloc, start); |
| 532 | BUG_ON(err == -EEXIST); |
| 533 | prealloc = NULL; |
| 534 | if (err) |
| 535 | goto out; |
| 536 | if (state->end <= end) { |
| 537 | start = state->end + 1; |
| 538 | set |= clear_state_bit(tree, state, bits, |
| 539 | wake, delete); |
| 540 | } else { |
| 541 | start = state->start; |
| 542 | } |
| 543 | goto search_again; |
| 544 | } |
| 545 | /* |
| 546 | * | ---- desired range ---- | |
| 547 | * | state | |
| 548 | * We need to split the extent, and clear the bit |
| 549 | * on the first half |
| 550 | */ |
| 551 | if (state->start <= end && state->end > end) { |
| 552 | err = split_state(tree, state, prealloc, end + 1); |
| 553 | BUG_ON(err == -EEXIST); |
| 554 | |
| 555 | if (wake) |
| 556 | wake_up(&state->wq); |
| 557 | set |= clear_state_bit(tree, prealloc, bits, |
| 558 | wake, delete); |
| 559 | prealloc = NULL; |
| 560 | goto out; |
| 561 | } |
| 562 | |
| 563 | start = state->end + 1; |
| 564 | set |= clear_state_bit(tree, state, bits, wake, delete); |
| 565 | goto search_again; |
| 566 | |
| 567 | out: |
Christoph Hellwig | 90f1c19 | 2007-09-10 20:02:27 -0400 | [diff] [blame] | 568 | write_unlock_irqrestore(&tree->lock, flags); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 569 | if (prealloc) |
| 570 | free_extent_state(prealloc); |
| 571 | |
| 572 | return set; |
| 573 | |
| 574 | search_again: |
Chris Mason | 96b5179 | 2007-10-15 16:15:19 -0400 | [diff] [blame] | 575 | if (start > end) |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 576 | goto out; |
Christoph Hellwig | 90f1c19 | 2007-09-10 20:02:27 -0400 | [diff] [blame] | 577 | write_unlock_irqrestore(&tree->lock, flags); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 578 | if (mask & __GFP_WAIT) |
| 579 | cond_resched(); |
| 580 | goto again; |
| 581 | } |
| 582 | EXPORT_SYMBOL(clear_extent_bit); |
| 583 | |
| 584 | static int wait_on_state(struct extent_map_tree *tree, |
| 585 | struct extent_state *state) |
| 586 | { |
| 587 | DEFINE_WAIT(wait); |
| 588 | prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); |
| 589 | read_unlock_irq(&tree->lock); |
| 590 | schedule(); |
| 591 | read_lock_irq(&tree->lock); |
| 592 | finish_wait(&state->wq, &wait); |
| 593 | return 0; |
| 594 | } |
| 595 | |
| 596 | /* |
| 597 | * waits for one or more bits to clear on a range in the state tree. |
| 598 | * The range [start, end] is inclusive. |
| 599 | * The tree lock is taken by this function |
| 600 | */ |
| 601 | int wait_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, int bits) |
| 602 | { |
| 603 | struct extent_state *state; |
| 604 | struct rb_node *node; |
| 605 | |
| 606 | read_lock_irq(&tree->lock); |
| 607 | again: |
| 608 | while (1) { |
| 609 | /* |
| 610 | * this search will find all the extents that end after |
| 611 | * our range starts |
| 612 | */ |
| 613 | node = tree_search(&tree->state, start); |
| 614 | if (!node) |
| 615 | break; |
| 616 | |
| 617 | state = rb_entry(node, struct extent_state, rb_node); |
| 618 | |
| 619 | if (state->start > end) |
| 620 | goto out; |
| 621 | |
| 622 | if (state->state & bits) { |
| 623 | start = state->start; |
| 624 | atomic_inc(&state->refs); |
| 625 | wait_on_state(tree, state); |
| 626 | free_extent_state(state); |
| 627 | goto again; |
| 628 | } |
| 629 | start = state->end + 1; |
| 630 | |
| 631 | if (start > end) |
| 632 | break; |
| 633 | |
| 634 | if (need_resched()) { |
| 635 | read_unlock_irq(&tree->lock); |
| 636 | cond_resched(); |
| 637 | read_lock_irq(&tree->lock); |
| 638 | } |
| 639 | } |
| 640 | out: |
| 641 | read_unlock_irq(&tree->lock); |
| 642 | return 0; |
| 643 | } |
| 644 | EXPORT_SYMBOL(wait_extent_bit); |
| 645 | |
| 646 | /* |
| 647 | * set some bits on a range in the tree. This may require allocations |
| 648 | * or sleeping, so the gfp mask is used to indicate what is allowed. |
| 649 | * |
| 650 | * If 'exclusive' == 1, this will fail with -EEXIST if some part of the |
| 651 | * range already has the desired bits set. The start of the existing |
| 652 | * range is returned in failed_start in this case. |
| 653 | * |
| 654 | * [start, end] is inclusive |
| 655 | * This takes the tree lock. |
| 656 | */ |
| 657 | int set_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, int bits, |
| 658 | int exclusive, u64 *failed_start, gfp_t mask) |
| 659 | { |
| 660 | struct extent_state *state; |
| 661 | struct extent_state *prealloc = NULL; |
| 662 | struct rb_node *node; |
Christoph Hellwig | 90f1c19 | 2007-09-10 20:02:27 -0400 | [diff] [blame] | 663 | unsigned long flags; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 664 | int err = 0; |
| 665 | int set; |
| 666 | u64 last_start; |
| 667 | u64 last_end; |
| 668 | again: |
| 669 | if (!prealloc && (mask & __GFP_WAIT)) { |
| 670 | prealloc = alloc_extent_state(mask); |
| 671 | if (!prealloc) |
| 672 | return -ENOMEM; |
| 673 | } |
| 674 | |
Christoph Hellwig | 90f1c19 | 2007-09-10 20:02:27 -0400 | [diff] [blame] | 675 | write_lock_irqsave(&tree->lock, flags); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 676 | /* |
| 677 | * this search will find all the extents that end after |
| 678 | * our range starts. |
| 679 | */ |
| 680 | node = tree_search(&tree->state, start); |
| 681 | if (!node) { |
| 682 | err = insert_state(tree, prealloc, start, end, bits); |
| 683 | prealloc = NULL; |
| 684 | BUG_ON(err == -EEXIST); |
| 685 | goto out; |
| 686 | } |
| 687 | |
| 688 | state = rb_entry(node, struct extent_state, rb_node); |
| 689 | last_start = state->start; |
| 690 | last_end = state->end; |
| 691 | |
| 692 | /* |
| 693 | * | ---- desired range ---- | |
| 694 | * | state | |
| 695 | * |
| 696 | * Just lock what we found and keep going |
| 697 | */ |
| 698 | if (state->start == start && state->end <= end) { |
| 699 | set = state->state & bits; |
| 700 | if (set && exclusive) { |
| 701 | *failed_start = state->start; |
| 702 | err = -EEXIST; |
| 703 | goto out; |
| 704 | } |
| 705 | state->state |= bits; |
| 706 | start = state->end + 1; |
| 707 | merge_state(tree, state); |
| 708 | goto search_again; |
| 709 | } |
| 710 | |
| 711 | /* |
| 712 | * | ---- desired range ---- | |
| 713 | * | state | |
| 714 | * or |
| 715 | * | ------------- state -------------- | |
| 716 | * |
| 717 | * We need to split the extent we found, and may flip bits on |
| 718 | * second half. |
| 719 | * |
| 720 | * If the extent we found extends past our |
| 721 | * range, we just split and search again. It'll get split |
| 722 | * again the next time though. |
| 723 | * |
| 724 | * If the extent we found is inside our range, we set the |
| 725 | * desired bit on it. |
| 726 | */ |
| 727 | if (state->start < start) { |
| 728 | set = state->state & bits; |
| 729 | if (exclusive && set) { |
| 730 | *failed_start = start; |
| 731 | err = -EEXIST; |
| 732 | goto out; |
| 733 | } |
| 734 | err = split_state(tree, state, prealloc, start); |
| 735 | BUG_ON(err == -EEXIST); |
| 736 | prealloc = NULL; |
| 737 | if (err) |
| 738 | goto out; |
| 739 | if (state->end <= end) { |
| 740 | state->state |= bits; |
| 741 | start = state->end + 1; |
| 742 | merge_state(tree, state); |
| 743 | } else { |
| 744 | start = state->start; |
| 745 | } |
| 746 | goto search_again; |
| 747 | } |
| 748 | /* |
| 749 | * | ---- desired range ---- | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 750 | * | state | or | state | |
| 751 | * |
| 752 | * There's a hole, we need to insert something in it and |
| 753 | * ignore the extent we found. |
| 754 | */ |
| 755 | if (state->start > start) { |
| 756 | u64 this_end; |
| 757 | if (end < last_start) |
| 758 | this_end = end; |
| 759 | else |
| 760 | this_end = last_start -1; |
| 761 | err = insert_state(tree, prealloc, start, this_end, |
| 762 | bits); |
| 763 | prealloc = NULL; |
| 764 | BUG_ON(err == -EEXIST); |
| 765 | if (err) |
| 766 | goto out; |
| 767 | start = this_end + 1; |
| 768 | goto search_again; |
| 769 | } |
Chris Mason | a8c450b | 2007-09-10 20:00:27 -0400 | [diff] [blame] | 770 | /* |
| 771 | * | ---- desired range ---- | |
| 772 | * | state | |
| 773 | * We need to split the extent, and set the bit |
| 774 | * on the first half |
| 775 | */ |
| 776 | if (state->start <= end && state->end > end) { |
| 777 | set = state->state & bits; |
| 778 | if (exclusive && set) { |
| 779 | *failed_start = start; |
| 780 | err = -EEXIST; |
| 781 | goto out; |
| 782 | } |
| 783 | err = split_state(tree, state, prealloc, end + 1); |
| 784 | BUG_ON(err == -EEXIST); |
| 785 | |
| 786 | prealloc->state |= bits; |
| 787 | merge_state(tree, prealloc); |
| 788 | prealloc = NULL; |
| 789 | goto out; |
| 790 | } |
| 791 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 792 | goto search_again; |
| 793 | |
| 794 | out: |
Christoph Hellwig | 90f1c19 | 2007-09-10 20:02:27 -0400 | [diff] [blame] | 795 | write_unlock_irqrestore(&tree->lock, flags); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 796 | if (prealloc) |
| 797 | free_extent_state(prealloc); |
| 798 | |
| 799 | return err; |
| 800 | |
| 801 | search_again: |
| 802 | if (start > end) |
| 803 | goto out; |
Christoph Hellwig | 90f1c19 | 2007-09-10 20:02:27 -0400 | [diff] [blame] | 804 | write_unlock_irqrestore(&tree->lock, flags); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 805 | if (mask & __GFP_WAIT) |
| 806 | cond_resched(); |
| 807 | goto again; |
| 808 | } |
| 809 | EXPORT_SYMBOL(set_extent_bit); |
| 810 | |
| 811 | /* wrappers around set/clear extent bit */ |
| 812 | int set_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, |
| 813 | gfp_t mask) |
| 814 | { |
| 815 | return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, |
| 816 | mask); |
| 817 | } |
| 818 | EXPORT_SYMBOL(set_extent_dirty); |
| 819 | |
Chris Mason | 96b5179 | 2007-10-15 16:15:19 -0400 | [diff] [blame] | 820 | int set_extent_bits(struct extent_map_tree *tree, u64 start, u64 end, |
| 821 | int bits, gfp_t mask) |
| 822 | { |
| 823 | return set_extent_bit(tree, start, end, bits, 0, NULL, |
| 824 | mask); |
| 825 | } |
| 826 | EXPORT_SYMBOL(set_extent_bits); |
| 827 | |
| 828 | int clear_extent_bits(struct extent_map_tree *tree, u64 start, u64 end, |
| 829 | int bits, gfp_t mask) |
| 830 | { |
| 831 | return clear_extent_bit(tree, start, end, bits, 0, 0, mask); |
| 832 | } |
| 833 | EXPORT_SYMBOL(clear_extent_bits); |
| 834 | |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 835 | int set_extent_delalloc(struct extent_map_tree *tree, u64 start, u64 end, |
| 836 | gfp_t mask) |
| 837 | { |
| 838 | return set_extent_bit(tree, start, end, |
| 839 | EXTENT_DELALLOC | EXTENT_DIRTY, 0, NULL, |
| 840 | mask); |
| 841 | } |
| 842 | EXPORT_SYMBOL(set_extent_delalloc); |
| 843 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 844 | int clear_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, |
| 845 | gfp_t mask) |
| 846 | { |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 847 | return clear_extent_bit(tree, start, end, |
| 848 | EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 849 | } |
| 850 | EXPORT_SYMBOL(clear_extent_dirty); |
| 851 | |
| 852 | int set_extent_new(struct extent_map_tree *tree, u64 start, u64 end, |
| 853 | gfp_t mask) |
| 854 | { |
| 855 | return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, |
| 856 | mask); |
| 857 | } |
| 858 | EXPORT_SYMBOL(set_extent_new); |
| 859 | |
| 860 | int clear_extent_new(struct extent_map_tree *tree, u64 start, u64 end, |
| 861 | gfp_t mask) |
| 862 | { |
| 863 | return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); |
| 864 | } |
| 865 | EXPORT_SYMBOL(clear_extent_new); |
| 866 | |
| 867 | int set_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, |
| 868 | gfp_t mask) |
| 869 | { |
| 870 | return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, |
| 871 | mask); |
| 872 | } |
| 873 | EXPORT_SYMBOL(set_extent_uptodate); |
| 874 | |
| 875 | int clear_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, |
| 876 | gfp_t mask) |
| 877 | { |
| 878 | return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); |
| 879 | } |
| 880 | EXPORT_SYMBOL(clear_extent_uptodate); |
| 881 | |
| 882 | int set_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end, |
| 883 | gfp_t mask) |
| 884 | { |
| 885 | return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, |
| 886 | 0, NULL, mask); |
| 887 | } |
| 888 | EXPORT_SYMBOL(set_extent_writeback); |
| 889 | |
| 890 | int clear_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end, |
| 891 | gfp_t mask) |
| 892 | { |
| 893 | return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask); |
| 894 | } |
| 895 | EXPORT_SYMBOL(clear_extent_writeback); |
| 896 | |
| 897 | int wait_on_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end) |
| 898 | { |
| 899 | return wait_extent_bit(tree, start, end, EXTENT_WRITEBACK); |
| 900 | } |
| 901 | EXPORT_SYMBOL(wait_on_extent_writeback); |
| 902 | |
| 903 | /* |
| 904 | * locks a range in ascending order, waiting for any locked regions |
| 905 | * it hits on the way. [start,end] are inclusive, and this will sleep. |
| 906 | */ |
| 907 | int lock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask) |
| 908 | { |
| 909 | int err; |
| 910 | u64 failed_start; |
| 911 | while (1) { |
| 912 | err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, |
| 913 | &failed_start, mask); |
| 914 | if (err == -EEXIST && (mask & __GFP_WAIT)) { |
| 915 | wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); |
| 916 | start = failed_start; |
| 917 | } else { |
| 918 | break; |
| 919 | } |
| 920 | WARN_ON(start > end); |
| 921 | } |
| 922 | return err; |
| 923 | } |
| 924 | EXPORT_SYMBOL(lock_extent); |
| 925 | |
| 926 | int unlock_extent(struct extent_map_tree *tree, u64 start, u64 end, |
| 927 | gfp_t mask) |
| 928 | { |
| 929 | return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); |
| 930 | } |
| 931 | EXPORT_SYMBOL(unlock_extent); |
| 932 | |
| 933 | /* |
| 934 | * helper function to set pages and extents in the tree dirty |
| 935 | */ |
| 936 | int set_range_dirty(struct extent_map_tree *tree, u64 start, u64 end) |
| 937 | { |
| 938 | unsigned long index = start >> PAGE_CACHE_SHIFT; |
| 939 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; |
| 940 | struct page *page; |
| 941 | |
| 942 | while (index <= end_index) { |
| 943 | page = find_get_page(tree->mapping, index); |
| 944 | BUG_ON(!page); |
| 945 | __set_page_dirty_nobuffers(page); |
| 946 | page_cache_release(page); |
| 947 | index++; |
| 948 | } |
| 949 | set_extent_dirty(tree, start, end, GFP_NOFS); |
| 950 | return 0; |
| 951 | } |
| 952 | EXPORT_SYMBOL(set_range_dirty); |
| 953 | |
| 954 | /* |
| 955 | * helper function to set both pages and extents in the tree writeback |
| 956 | */ |
| 957 | int set_range_writeback(struct extent_map_tree *tree, u64 start, u64 end) |
| 958 | { |
| 959 | unsigned long index = start >> PAGE_CACHE_SHIFT; |
| 960 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; |
| 961 | struct page *page; |
| 962 | |
| 963 | while (index <= end_index) { |
| 964 | page = find_get_page(tree->mapping, index); |
| 965 | BUG_ON(!page); |
| 966 | set_page_writeback(page); |
| 967 | page_cache_release(page); |
| 968 | index++; |
| 969 | } |
| 970 | set_extent_writeback(tree, start, end, GFP_NOFS); |
| 971 | return 0; |
| 972 | } |
| 973 | EXPORT_SYMBOL(set_range_writeback); |
| 974 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 975 | int find_first_extent_bit(struct extent_map_tree *tree, u64 start, |
| 976 | u64 *start_ret, u64 *end_ret, int bits) |
| 977 | { |
| 978 | struct rb_node *node; |
| 979 | struct extent_state *state; |
| 980 | int ret = 1; |
| 981 | |
Chris Mason | e19caa5 | 2007-10-15 16:17:44 -0400 | [diff] [blame] | 982 | read_lock_irq(&tree->lock); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 983 | /* |
| 984 | * this search will find all the extents that end after |
| 985 | * our range starts. |
| 986 | */ |
| 987 | node = tree_search(&tree->state, start); |
| 988 | if (!node || IS_ERR(node)) { |
| 989 | goto out; |
| 990 | } |
| 991 | |
| 992 | while(1) { |
| 993 | state = rb_entry(node, struct extent_state, rb_node); |
Chris Mason | e19caa5 | 2007-10-15 16:17:44 -0400 | [diff] [blame] | 994 | if (state->end >= start && (state->state & bits)) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 995 | *start_ret = state->start; |
| 996 | *end_ret = state->end; |
| 997 | ret = 0; |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 998 | break; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 999 | } |
| 1000 | node = rb_next(node); |
| 1001 | if (!node) |
| 1002 | break; |
| 1003 | } |
| 1004 | out: |
Chris Mason | e19caa5 | 2007-10-15 16:17:44 -0400 | [diff] [blame] | 1005 | read_unlock_irq(&tree->lock); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1006 | return ret; |
| 1007 | } |
| 1008 | EXPORT_SYMBOL(find_first_extent_bit); |
| 1009 | |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1010 | u64 find_lock_delalloc_range(struct extent_map_tree *tree, |
| 1011 | u64 start, u64 lock_start, u64 *end, u64 max_bytes) |
| 1012 | { |
| 1013 | struct rb_node *node; |
| 1014 | struct extent_state *state; |
| 1015 | u64 cur_start = start; |
| 1016 | u64 found = 0; |
| 1017 | u64 total_bytes = 0; |
| 1018 | |
| 1019 | write_lock_irq(&tree->lock); |
| 1020 | /* |
| 1021 | * this search will find all the extents that end after |
| 1022 | * our range starts. |
| 1023 | */ |
| 1024 | search_again: |
| 1025 | node = tree_search(&tree->state, cur_start); |
| 1026 | if (!node || IS_ERR(node)) { |
| 1027 | goto out; |
| 1028 | } |
| 1029 | |
| 1030 | while(1) { |
| 1031 | state = rb_entry(node, struct extent_state, rb_node); |
| 1032 | if (state->start != cur_start) { |
| 1033 | goto out; |
| 1034 | } |
| 1035 | if (!(state->state & EXTENT_DELALLOC)) { |
| 1036 | goto out; |
| 1037 | } |
| 1038 | if (state->start >= lock_start) { |
| 1039 | if (state->state & EXTENT_LOCKED) { |
| 1040 | DEFINE_WAIT(wait); |
| 1041 | atomic_inc(&state->refs); |
| 1042 | write_unlock_irq(&tree->lock); |
| 1043 | schedule(); |
| 1044 | write_lock_irq(&tree->lock); |
| 1045 | finish_wait(&state->wq, &wait); |
| 1046 | free_extent_state(state); |
| 1047 | goto search_again; |
| 1048 | } |
| 1049 | state->state |= EXTENT_LOCKED; |
| 1050 | } |
| 1051 | found++; |
| 1052 | *end = state->end; |
| 1053 | cur_start = state->end + 1; |
| 1054 | node = rb_next(node); |
| 1055 | if (!node) |
| 1056 | break; |
| 1057 | total_bytes = state->end - state->start + 1; |
| 1058 | if (total_bytes >= max_bytes) |
| 1059 | break; |
| 1060 | } |
| 1061 | out: |
| 1062 | write_unlock_irq(&tree->lock); |
| 1063 | return found; |
| 1064 | } |
| 1065 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1066 | /* |
| 1067 | * helper function to lock both pages and extents in the tree. |
| 1068 | * pages must be locked first. |
| 1069 | */ |
| 1070 | int lock_range(struct extent_map_tree *tree, u64 start, u64 end) |
| 1071 | { |
| 1072 | unsigned long index = start >> PAGE_CACHE_SHIFT; |
| 1073 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; |
| 1074 | struct page *page; |
| 1075 | int err; |
| 1076 | |
| 1077 | while (index <= end_index) { |
| 1078 | page = grab_cache_page(tree->mapping, index); |
| 1079 | if (!page) { |
| 1080 | err = -ENOMEM; |
| 1081 | goto failed; |
| 1082 | } |
| 1083 | if (IS_ERR(page)) { |
| 1084 | err = PTR_ERR(page); |
| 1085 | goto failed; |
| 1086 | } |
| 1087 | index++; |
| 1088 | } |
| 1089 | lock_extent(tree, start, end, GFP_NOFS); |
| 1090 | return 0; |
| 1091 | |
| 1092 | failed: |
| 1093 | /* |
| 1094 | * we failed above in getting the page at 'index', so we undo here |
| 1095 | * up to but not including the page at 'index' |
| 1096 | */ |
| 1097 | end_index = index; |
| 1098 | index = start >> PAGE_CACHE_SHIFT; |
| 1099 | while (index < end_index) { |
| 1100 | page = find_get_page(tree->mapping, index); |
| 1101 | unlock_page(page); |
| 1102 | page_cache_release(page); |
| 1103 | index++; |
| 1104 | } |
| 1105 | return err; |
| 1106 | } |
| 1107 | EXPORT_SYMBOL(lock_range); |
| 1108 | |
| 1109 | /* |
| 1110 | * helper function to unlock both pages and extents in the tree. |
| 1111 | */ |
| 1112 | int unlock_range(struct extent_map_tree *tree, u64 start, u64 end) |
| 1113 | { |
| 1114 | unsigned long index = start >> PAGE_CACHE_SHIFT; |
| 1115 | unsigned long end_index = end >> PAGE_CACHE_SHIFT; |
| 1116 | struct page *page; |
| 1117 | |
| 1118 | while (index <= end_index) { |
| 1119 | page = find_get_page(tree->mapping, index); |
| 1120 | unlock_page(page); |
| 1121 | page_cache_release(page); |
| 1122 | index++; |
| 1123 | } |
| 1124 | unlock_extent(tree, start, end, GFP_NOFS); |
| 1125 | return 0; |
| 1126 | } |
| 1127 | EXPORT_SYMBOL(unlock_range); |
| 1128 | |
Chris Mason | 07157aa | 2007-08-30 08:50:51 -0400 | [diff] [blame] | 1129 | int set_state_private(struct extent_map_tree *tree, u64 start, u64 private) |
| 1130 | { |
| 1131 | struct rb_node *node; |
| 1132 | struct extent_state *state; |
| 1133 | int ret = 0; |
| 1134 | |
| 1135 | write_lock_irq(&tree->lock); |
| 1136 | /* |
| 1137 | * this search will find all the extents that end after |
| 1138 | * our range starts. |
| 1139 | */ |
| 1140 | node = tree_search(&tree->state, start); |
| 1141 | if (!node || IS_ERR(node)) { |
| 1142 | ret = -ENOENT; |
| 1143 | goto out; |
| 1144 | } |
| 1145 | state = rb_entry(node, struct extent_state, rb_node); |
| 1146 | if (state->start != start) { |
| 1147 | ret = -ENOENT; |
| 1148 | goto out; |
| 1149 | } |
| 1150 | state->private = private; |
| 1151 | out: |
| 1152 | write_unlock_irq(&tree->lock); |
| 1153 | return ret; |
Chris Mason | 07157aa | 2007-08-30 08:50:51 -0400 | [diff] [blame] | 1154 | } |
| 1155 | |
| 1156 | int get_state_private(struct extent_map_tree *tree, u64 start, u64 *private) |
| 1157 | { |
| 1158 | struct rb_node *node; |
| 1159 | struct extent_state *state; |
| 1160 | int ret = 0; |
| 1161 | |
| 1162 | read_lock_irq(&tree->lock); |
| 1163 | /* |
| 1164 | * this search will find all the extents that end after |
| 1165 | * our range starts. |
| 1166 | */ |
| 1167 | node = tree_search(&tree->state, start); |
| 1168 | if (!node || IS_ERR(node)) { |
| 1169 | ret = -ENOENT; |
| 1170 | goto out; |
| 1171 | } |
| 1172 | state = rb_entry(node, struct extent_state, rb_node); |
| 1173 | if (state->start != start) { |
| 1174 | ret = -ENOENT; |
| 1175 | goto out; |
| 1176 | } |
| 1177 | *private = state->private; |
| 1178 | out: |
| 1179 | read_unlock_irq(&tree->lock); |
| 1180 | return ret; |
| 1181 | } |
| 1182 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1183 | /* |
| 1184 | * searches a range in the state tree for a given mask. |
| 1185 | * If 'filled' == 1, this returns 1 only if ever extent in the tree |
| 1186 | * has the bits set. Otherwise, 1 is returned if any bit in the |
| 1187 | * range is found set. |
| 1188 | */ |
Chris Mason | 1a5bc16 | 2007-10-15 16:15:26 -0400 | [diff] [blame] | 1189 | int test_range_bit(struct extent_map_tree *tree, u64 start, u64 end, |
| 1190 | int bits, int filled) |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1191 | { |
| 1192 | struct extent_state *state = NULL; |
| 1193 | struct rb_node *node; |
| 1194 | int bitset = 0; |
| 1195 | |
| 1196 | read_lock_irq(&tree->lock); |
| 1197 | node = tree_search(&tree->state, start); |
| 1198 | while (node && start <= end) { |
| 1199 | state = rb_entry(node, struct extent_state, rb_node); |
| 1200 | if (state->start > end) |
| 1201 | break; |
| 1202 | |
| 1203 | if (filled && state->start > start) { |
| 1204 | bitset = 0; |
| 1205 | break; |
| 1206 | } |
| 1207 | if (state->state & bits) { |
| 1208 | bitset = 1; |
| 1209 | if (!filled) |
| 1210 | break; |
| 1211 | } else if (filled) { |
| 1212 | bitset = 0; |
| 1213 | break; |
| 1214 | } |
| 1215 | start = state->end + 1; |
| 1216 | if (start > end) |
| 1217 | break; |
| 1218 | node = rb_next(node); |
| 1219 | } |
| 1220 | read_unlock_irq(&tree->lock); |
| 1221 | return bitset; |
| 1222 | } |
Chris Mason | 1a5bc16 | 2007-10-15 16:15:26 -0400 | [diff] [blame] | 1223 | EXPORT_SYMBOL(test_range_bit); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1224 | |
| 1225 | /* |
| 1226 | * helper function to set a given page up to date if all the |
| 1227 | * extents in the tree for that page are up to date |
| 1228 | */ |
| 1229 | static int check_page_uptodate(struct extent_map_tree *tree, |
| 1230 | struct page *page) |
| 1231 | { |
| 1232 | u64 start = page->index << PAGE_CACHE_SHIFT; |
| 1233 | u64 end = start + PAGE_CACHE_SIZE - 1; |
| 1234 | if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1)) |
| 1235 | SetPageUptodate(page); |
| 1236 | return 0; |
| 1237 | } |
| 1238 | |
| 1239 | /* |
| 1240 | * helper function to unlock a page if all the extents in the tree |
| 1241 | * for that page are unlocked |
| 1242 | */ |
| 1243 | static int check_page_locked(struct extent_map_tree *tree, |
| 1244 | struct page *page) |
| 1245 | { |
| 1246 | u64 start = page->index << PAGE_CACHE_SHIFT; |
| 1247 | u64 end = start + PAGE_CACHE_SIZE - 1; |
| 1248 | if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0)) |
| 1249 | unlock_page(page); |
| 1250 | return 0; |
| 1251 | } |
| 1252 | |
| 1253 | /* |
| 1254 | * helper function to end page writeback if all the extents |
| 1255 | * in the tree for that page are done with writeback |
| 1256 | */ |
| 1257 | static int check_page_writeback(struct extent_map_tree *tree, |
| 1258 | struct page *page) |
| 1259 | { |
| 1260 | u64 start = page->index << PAGE_CACHE_SHIFT; |
| 1261 | u64 end = start + PAGE_CACHE_SIZE - 1; |
| 1262 | if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0)) |
| 1263 | end_page_writeback(page); |
| 1264 | return 0; |
| 1265 | } |
| 1266 | |
| 1267 | /* lots and lots of room for performance fixes in the end_bio funcs */ |
| 1268 | |
| 1269 | /* |
| 1270 | * after a writepage IO is done, we need to: |
| 1271 | * clear the uptodate bits on error |
| 1272 | * clear the writeback bits in the extent tree for this IO |
| 1273 | * end_page_writeback if the page has no more pending IO |
| 1274 | * |
| 1275 | * Scheduling is not allowed, so the extent state tree is expected |
| 1276 | * to have one and only one object corresponding to this IO. |
| 1277 | */ |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1278 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
| 1279 | static void end_bio_extent_writepage(struct bio *bio, int err) |
| 1280 | #else |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1281 | static int end_bio_extent_writepage(struct bio *bio, |
| 1282 | unsigned int bytes_done, int err) |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1283 | #endif |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1284 | { |
| 1285 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); |
| 1286 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
| 1287 | struct extent_map_tree *tree = bio->bi_private; |
| 1288 | u64 start; |
| 1289 | u64 end; |
| 1290 | int whole_page; |
| 1291 | |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1292 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1293 | if (bio->bi_size) |
| 1294 | return 1; |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1295 | #endif |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1296 | |
| 1297 | do { |
| 1298 | struct page *page = bvec->bv_page; |
| 1299 | start = (page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; |
| 1300 | end = start + bvec->bv_len - 1; |
| 1301 | |
| 1302 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) |
| 1303 | whole_page = 1; |
| 1304 | else |
| 1305 | whole_page = 0; |
| 1306 | |
| 1307 | if (--bvec >= bio->bi_io_vec) |
| 1308 | prefetchw(&bvec->bv_page->flags); |
| 1309 | |
| 1310 | if (!uptodate) { |
| 1311 | clear_extent_uptodate(tree, start, end, GFP_ATOMIC); |
| 1312 | ClearPageUptodate(page); |
| 1313 | SetPageError(page); |
| 1314 | } |
| 1315 | clear_extent_writeback(tree, start, end, GFP_ATOMIC); |
| 1316 | |
| 1317 | if (whole_page) |
| 1318 | end_page_writeback(page); |
| 1319 | else |
| 1320 | check_page_writeback(tree, page); |
Christoph Hellwig | 0e2752a | 2007-09-10 20:02:33 -0400 | [diff] [blame] | 1321 | if (tree->ops && tree->ops->writepage_end_io_hook) |
| 1322 | tree->ops->writepage_end_io_hook(page, start, end); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1323 | } while (bvec >= bio->bi_io_vec); |
| 1324 | |
| 1325 | bio_put(bio); |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1326 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1327 | return 0; |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1328 | #endif |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1329 | } |
| 1330 | |
| 1331 | /* |
| 1332 | * after a readpage IO is done, we need to: |
| 1333 | * clear the uptodate bits on error |
| 1334 | * set the uptodate bits if things worked |
| 1335 | * set the page up to date if all extents in the tree are uptodate |
| 1336 | * clear the lock bit in the extent tree |
| 1337 | * unlock the page if there are no other extents locked for it |
| 1338 | * |
| 1339 | * Scheduling is not allowed, so the extent state tree is expected |
| 1340 | * to have one and only one object corresponding to this IO. |
| 1341 | */ |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1342 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
| 1343 | static void end_bio_extent_readpage(struct bio *bio, int err) |
| 1344 | #else |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1345 | static int end_bio_extent_readpage(struct bio *bio, |
| 1346 | unsigned int bytes_done, int err) |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1347 | #endif |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1348 | { |
Chris Mason | 07157aa | 2007-08-30 08:50:51 -0400 | [diff] [blame] | 1349 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1350 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
| 1351 | struct extent_map_tree *tree = bio->bi_private; |
| 1352 | u64 start; |
| 1353 | u64 end; |
| 1354 | int whole_page; |
Chris Mason | 07157aa | 2007-08-30 08:50:51 -0400 | [diff] [blame] | 1355 | int ret; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1356 | |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1357 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1358 | if (bio->bi_size) |
| 1359 | return 1; |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1360 | #endif |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1361 | |
| 1362 | do { |
| 1363 | struct page *page = bvec->bv_page; |
| 1364 | start = (page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; |
| 1365 | end = start + bvec->bv_len - 1; |
| 1366 | |
| 1367 | if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE) |
| 1368 | whole_page = 1; |
| 1369 | else |
| 1370 | whole_page = 0; |
| 1371 | |
| 1372 | if (--bvec >= bio->bi_io_vec) |
| 1373 | prefetchw(&bvec->bv_page->flags); |
| 1374 | |
Chris Mason | 07157aa | 2007-08-30 08:50:51 -0400 | [diff] [blame] | 1375 | if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) { |
| 1376 | ret = tree->ops->readpage_end_io_hook(page, start, end); |
| 1377 | if (ret) |
| 1378 | uptodate = 0; |
| 1379 | } |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1380 | if (uptodate) { |
| 1381 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); |
| 1382 | if (whole_page) |
| 1383 | SetPageUptodate(page); |
| 1384 | else |
| 1385 | check_page_uptodate(tree, page); |
| 1386 | } else { |
| 1387 | ClearPageUptodate(page); |
| 1388 | SetPageError(page); |
| 1389 | } |
| 1390 | |
| 1391 | unlock_extent(tree, start, end, GFP_ATOMIC); |
| 1392 | |
| 1393 | if (whole_page) |
| 1394 | unlock_page(page); |
| 1395 | else |
| 1396 | check_page_locked(tree, page); |
| 1397 | } while (bvec >= bio->bi_io_vec); |
| 1398 | |
| 1399 | bio_put(bio); |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1400 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1401 | return 0; |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1402 | #endif |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1403 | } |
| 1404 | |
| 1405 | /* |
| 1406 | * IO done from prepare_write is pretty simple, we just unlock |
| 1407 | * the structs in the extent tree when done, and set the uptodate bits |
| 1408 | * as appropriate. |
| 1409 | */ |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1410 | #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
| 1411 | static void end_bio_extent_preparewrite(struct bio *bio, int err) |
| 1412 | #else |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1413 | static int end_bio_extent_preparewrite(struct bio *bio, |
| 1414 | unsigned int bytes_done, int err) |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1415 | #endif |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1416 | { |
| 1417 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); |
| 1418 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
| 1419 | struct extent_map_tree *tree = bio->bi_private; |
| 1420 | u64 start; |
| 1421 | u64 end; |
| 1422 | |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1423 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1424 | if (bio->bi_size) |
| 1425 | return 1; |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1426 | #endif |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1427 | |
| 1428 | do { |
| 1429 | struct page *page = bvec->bv_page; |
| 1430 | start = (page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset; |
| 1431 | end = start + bvec->bv_len - 1; |
| 1432 | |
| 1433 | if (--bvec >= bio->bi_io_vec) |
| 1434 | prefetchw(&bvec->bv_page->flags); |
| 1435 | |
| 1436 | if (uptodate) { |
| 1437 | set_extent_uptodate(tree, start, end, GFP_ATOMIC); |
| 1438 | } else { |
| 1439 | ClearPageUptodate(page); |
| 1440 | SetPageError(page); |
| 1441 | } |
| 1442 | |
| 1443 | unlock_extent(tree, start, end, GFP_ATOMIC); |
| 1444 | |
| 1445 | } while (bvec >= bio->bi_io_vec); |
| 1446 | |
| 1447 | bio_put(bio); |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1448 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1449 | return 0; |
Jens Axboe | 0a2118d | 2007-10-19 09:23:05 -0400 | [diff] [blame^] | 1450 | #endif |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1451 | } |
| 1452 | |
| 1453 | static int submit_extent_page(int rw, struct extent_map_tree *tree, |
| 1454 | struct page *page, sector_t sector, |
| 1455 | size_t size, unsigned long offset, |
| 1456 | struct block_device *bdev, |
| 1457 | bio_end_io_t end_io_func) |
| 1458 | { |
| 1459 | struct bio *bio; |
| 1460 | int ret = 0; |
| 1461 | |
| 1462 | bio = bio_alloc(GFP_NOIO, 1); |
| 1463 | |
| 1464 | bio->bi_sector = sector; |
| 1465 | bio->bi_bdev = bdev; |
| 1466 | bio->bi_io_vec[0].bv_page = page; |
| 1467 | bio->bi_io_vec[0].bv_len = size; |
| 1468 | bio->bi_io_vec[0].bv_offset = offset; |
| 1469 | |
| 1470 | bio->bi_vcnt = 1; |
| 1471 | bio->bi_idx = 0; |
| 1472 | bio->bi_size = size; |
| 1473 | |
| 1474 | bio->bi_end_io = end_io_func; |
| 1475 | bio->bi_private = tree; |
| 1476 | |
| 1477 | bio_get(bio); |
| 1478 | submit_bio(rw, bio); |
| 1479 | |
| 1480 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) |
| 1481 | ret = -EOPNOTSUPP; |
| 1482 | |
| 1483 | bio_put(bio); |
| 1484 | return ret; |
| 1485 | } |
| 1486 | |
Christoph Hellwig | b3cfa35 | 2007-09-17 11:25:58 -0400 | [diff] [blame] | 1487 | void set_page_extent_mapped(struct page *page) |
| 1488 | { |
| 1489 | if (!PagePrivate(page)) { |
| 1490 | SetPagePrivate(page); |
| 1491 | WARN_ON(!page->mapping->a_ops->invalidatepage); |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 1492 | set_page_private(page, EXTENT_PAGE_PRIVATE); |
Christoph Hellwig | b3cfa35 | 2007-09-17 11:25:58 -0400 | [diff] [blame] | 1493 | page_cache_get(page); |
| 1494 | } |
| 1495 | } |
| 1496 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1497 | /* |
| 1498 | * basic readpage implementation. Locked extent state structs are inserted |
| 1499 | * into the tree that are removed when the IO is done (by the end_io |
| 1500 | * handlers) |
| 1501 | */ |
| 1502 | int extent_read_full_page(struct extent_map_tree *tree, struct page *page, |
| 1503 | get_extent_t *get_extent) |
| 1504 | { |
| 1505 | struct inode *inode = page->mapping->host; |
| 1506 | u64 start = page->index << PAGE_CACHE_SHIFT; |
| 1507 | u64 page_end = start + PAGE_CACHE_SIZE - 1; |
| 1508 | u64 end; |
| 1509 | u64 cur = start; |
| 1510 | u64 extent_offset; |
| 1511 | u64 last_byte = i_size_read(inode); |
| 1512 | u64 block_start; |
| 1513 | u64 cur_end; |
| 1514 | sector_t sector; |
| 1515 | struct extent_map *em; |
| 1516 | struct block_device *bdev; |
| 1517 | int ret; |
| 1518 | int nr = 0; |
| 1519 | size_t page_offset = 0; |
| 1520 | size_t iosize; |
| 1521 | size_t blocksize = inode->i_sb->s_blocksize; |
| 1522 | |
Christoph Hellwig | b3cfa35 | 2007-09-17 11:25:58 -0400 | [diff] [blame] | 1523 | set_page_extent_mapped(page); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1524 | |
| 1525 | end = page_end; |
| 1526 | lock_extent(tree, start, end, GFP_NOFS); |
| 1527 | |
| 1528 | while (cur <= end) { |
| 1529 | if (cur >= last_byte) { |
| 1530 | iosize = PAGE_CACHE_SIZE - page_offset; |
| 1531 | zero_user_page(page, page_offset, iosize, KM_USER0); |
| 1532 | set_extent_uptodate(tree, cur, cur + iosize - 1, |
| 1533 | GFP_NOFS); |
| 1534 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); |
| 1535 | break; |
| 1536 | } |
| 1537 | em = get_extent(inode, page, page_offset, cur, end, 0); |
| 1538 | if (IS_ERR(em) || !em) { |
| 1539 | SetPageError(page); |
| 1540 | unlock_extent(tree, cur, end, GFP_NOFS); |
| 1541 | break; |
| 1542 | } |
| 1543 | |
| 1544 | extent_offset = cur - em->start; |
| 1545 | BUG_ON(em->end < cur); |
| 1546 | BUG_ON(end < cur); |
| 1547 | |
| 1548 | iosize = min(em->end - cur, end - cur) + 1; |
| 1549 | cur_end = min(em->end, end); |
| 1550 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); |
| 1551 | sector = (em->block_start + extent_offset) >> 9; |
| 1552 | bdev = em->bdev; |
| 1553 | block_start = em->block_start; |
| 1554 | free_extent_map(em); |
| 1555 | em = NULL; |
| 1556 | |
| 1557 | /* we've found a hole, just zero and go on */ |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1558 | if (block_start == EXTENT_MAP_HOLE) { |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1559 | zero_user_page(page, page_offset, iosize, KM_USER0); |
| 1560 | set_extent_uptodate(tree, cur, cur + iosize - 1, |
| 1561 | GFP_NOFS); |
| 1562 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); |
| 1563 | cur = cur + iosize; |
| 1564 | page_offset += iosize; |
| 1565 | continue; |
| 1566 | } |
| 1567 | /* the get_extent function already copied into the page */ |
| 1568 | if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) { |
| 1569 | unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS); |
| 1570 | cur = cur + iosize; |
| 1571 | page_offset += iosize; |
| 1572 | continue; |
| 1573 | } |
| 1574 | |
Chris Mason | 07157aa | 2007-08-30 08:50:51 -0400 | [diff] [blame] | 1575 | ret = 0; |
| 1576 | if (tree->ops && tree->ops->readpage_io_hook) { |
| 1577 | ret = tree->ops->readpage_io_hook(page, cur, |
| 1578 | cur + iosize - 1); |
| 1579 | } |
| 1580 | if (!ret) { |
| 1581 | ret = submit_extent_page(READ, tree, page, |
| 1582 | sector, iosize, page_offset, |
| 1583 | bdev, end_bio_extent_readpage); |
| 1584 | } |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1585 | if (ret) |
| 1586 | SetPageError(page); |
| 1587 | cur = cur + iosize; |
| 1588 | page_offset += iosize; |
| 1589 | nr++; |
| 1590 | } |
| 1591 | if (!nr) { |
| 1592 | if (!PageError(page)) |
| 1593 | SetPageUptodate(page); |
| 1594 | unlock_page(page); |
| 1595 | } |
| 1596 | return 0; |
| 1597 | } |
| 1598 | EXPORT_SYMBOL(extent_read_full_page); |
| 1599 | |
| 1600 | /* |
| 1601 | * the writepage semantics are similar to regular writepage. extent |
| 1602 | * records are inserted to lock ranges in the tree, and as dirty areas |
| 1603 | * are found, they are marked writeback. Then the lock bits are removed |
| 1604 | * and the end_io handler clears the writeback ranges |
| 1605 | */ |
| 1606 | int extent_write_full_page(struct extent_map_tree *tree, struct page *page, |
| 1607 | get_extent_t *get_extent, |
| 1608 | struct writeback_control *wbc) |
| 1609 | { |
| 1610 | struct inode *inode = page->mapping->host; |
| 1611 | u64 start = page->index << PAGE_CACHE_SHIFT; |
| 1612 | u64 page_end = start + PAGE_CACHE_SIZE - 1; |
| 1613 | u64 end; |
| 1614 | u64 cur = start; |
| 1615 | u64 extent_offset; |
| 1616 | u64 last_byte = i_size_read(inode); |
| 1617 | u64 block_start; |
| 1618 | sector_t sector; |
| 1619 | struct extent_map *em; |
| 1620 | struct block_device *bdev; |
| 1621 | int ret; |
| 1622 | int nr = 0; |
| 1623 | size_t page_offset = 0; |
| 1624 | size_t iosize; |
| 1625 | size_t blocksize; |
| 1626 | loff_t i_size = i_size_read(inode); |
| 1627 | unsigned long end_index = i_size >> PAGE_CACHE_SHIFT; |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1628 | u64 nr_delalloc; |
| 1629 | u64 delalloc_end; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1630 | |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1631 | WARN_ON(!PageLocked(page)); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1632 | if (page->index > end_index) { |
| 1633 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); |
| 1634 | unlock_page(page); |
| 1635 | return 0; |
| 1636 | } |
| 1637 | |
| 1638 | if (page->index == end_index) { |
| 1639 | size_t offset = i_size & (PAGE_CACHE_SIZE - 1); |
| 1640 | zero_user_page(page, offset, |
| 1641 | PAGE_CACHE_SIZE - offset, KM_USER0); |
| 1642 | } |
| 1643 | |
Christoph Hellwig | b3cfa35 | 2007-09-17 11:25:58 -0400 | [diff] [blame] | 1644 | set_page_extent_mapped(page); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1645 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1646 | lock_extent(tree, start, page_end, GFP_NOFS); |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1647 | nr_delalloc = find_lock_delalloc_range(tree, start, page_end + 1, |
| 1648 | &delalloc_end, |
| 1649 | 128 * 1024 * 1024); |
| 1650 | if (nr_delalloc) { |
Chris Mason | 07157aa | 2007-08-30 08:50:51 -0400 | [diff] [blame] | 1651 | tree->ops->fill_delalloc(inode, start, delalloc_end); |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1652 | if (delalloc_end >= page_end + 1) { |
| 1653 | clear_extent_bit(tree, page_end + 1, delalloc_end, |
| 1654 | EXTENT_LOCKED | EXTENT_DELALLOC, |
| 1655 | 1, 0, GFP_NOFS); |
| 1656 | } |
| 1657 | clear_extent_bit(tree, start, page_end, EXTENT_DELALLOC, |
| 1658 | 0, 0, GFP_NOFS); |
| 1659 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { |
| 1660 | printk("found delalloc bits after clear extent_bit\n"); |
| 1661 | } |
| 1662 | } else if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { |
| 1663 | printk("found delalloc bits after find_delalloc_range returns 0\n"); |
| 1664 | } |
| 1665 | |
| 1666 | end = page_end; |
| 1667 | if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0)) { |
| 1668 | printk("found delalloc bits after lock_extent\n"); |
| 1669 | } |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1670 | |
| 1671 | if (last_byte <= start) { |
| 1672 | clear_extent_dirty(tree, start, page_end, GFP_NOFS); |
| 1673 | goto done; |
| 1674 | } |
| 1675 | |
| 1676 | set_extent_uptodate(tree, start, page_end, GFP_NOFS); |
| 1677 | blocksize = inode->i_sb->s_blocksize; |
| 1678 | |
| 1679 | while (cur <= end) { |
| 1680 | if (cur >= last_byte) { |
| 1681 | clear_extent_dirty(tree, cur, page_end, GFP_NOFS); |
| 1682 | break; |
| 1683 | } |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1684 | em = get_extent(inode, page, page_offset, cur, end, 0); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1685 | if (IS_ERR(em) || !em) { |
| 1686 | SetPageError(page); |
| 1687 | break; |
| 1688 | } |
| 1689 | |
| 1690 | extent_offset = cur - em->start; |
| 1691 | BUG_ON(em->end < cur); |
| 1692 | BUG_ON(end < cur); |
| 1693 | iosize = min(em->end - cur, end - cur) + 1; |
| 1694 | iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1); |
| 1695 | sector = (em->block_start + extent_offset) >> 9; |
| 1696 | bdev = em->bdev; |
| 1697 | block_start = em->block_start; |
| 1698 | free_extent_map(em); |
| 1699 | em = NULL; |
| 1700 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1701 | if (block_start == EXTENT_MAP_HOLE || |
| 1702 | block_start == EXTENT_MAP_INLINE) { |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1703 | clear_extent_dirty(tree, cur, |
| 1704 | cur + iosize - 1, GFP_NOFS); |
| 1705 | cur = cur + iosize; |
| 1706 | page_offset += iosize; |
| 1707 | continue; |
| 1708 | } |
| 1709 | |
| 1710 | /* leave this out until we have a page_mkwrite call */ |
| 1711 | if (0 && !test_range_bit(tree, cur, cur + iosize - 1, |
| 1712 | EXTENT_DIRTY, 0)) { |
| 1713 | cur = cur + iosize; |
| 1714 | page_offset += iosize; |
| 1715 | continue; |
| 1716 | } |
| 1717 | clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS); |
Christoph Hellwig | b06355f | 2007-09-10 20:02:32 -0400 | [diff] [blame] | 1718 | if (tree->ops && tree->ops->writepage_io_hook) { |
| 1719 | ret = tree->ops->writepage_io_hook(page, cur, |
| 1720 | cur + iosize - 1); |
| 1721 | } else { |
| 1722 | ret = 0; |
| 1723 | } |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1724 | if (ret) |
| 1725 | SetPageError(page); |
Chris Mason | 07157aa | 2007-08-30 08:50:51 -0400 | [diff] [blame] | 1726 | else { |
| 1727 | set_range_writeback(tree, cur, cur + iosize - 1); |
| 1728 | ret = submit_extent_page(WRITE, tree, page, sector, |
| 1729 | iosize, page_offset, bdev, |
| 1730 | end_bio_extent_writepage); |
| 1731 | if (ret) |
| 1732 | SetPageError(page); |
| 1733 | } |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1734 | cur = cur + iosize; |
| 1735 | page_offset += iosize; |
| 1736 | nr++; |
| 1737 | } |
| 1738 | done: |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1739 | unlock_extent(tree, start, page_end, GFP_NOFS); |
| 1740 | unlock_page(page); |
| 1741 | return 0; |
| 1742 | } |
| 1743 | EXPORT_SYMBOL(extent_write_full_page); |
| 1744 | |
| 1745 | /* |
| 1746 | * basic invalidatepage code, this waits on any locked or writeback |
| 1747 | * ranges corresponding to the page, and then deletes any extent state |
| 1748 | * records from the tree |
| 1749 | */ |
| 1750 | int extent_invalidatepage(struct extent_map_tree *tree, |
| 1751 | struct page *page, unsigned long offset) |
| 1752 | { |
| 1753 | u64 start = (page->index << PAGE_CACHE_SHIFT); |
| 1754 | u64 end = start + PAGE_CACHE_SIZE - 1; |
| 1755 | size_t blocksize = page->mapping->host->i_sb->s_blocksize; |
| 1756 | |
| 1757 | start += (offset + blocksize -1) & ~(blocksize - 1); |
| 1758 | if (start > end) |
| 1759 | return 0; |
| 1760 | |
| 1761 | lock_extent(tree, start, end, GFP_NOFS); |
| 1762 | wait_on_extent_writeback(tree, start, end); |
Chris Mason | 2bf5a72 | 2007-08-30 11:54:02 -0400 | [diff] [blame] | 1763 | clear_extent_bit(tree, start, end, |
| 1764 | EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC, |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1765 | 1, 1, GFP_NOFS); |
| 1766 | return 0; |
| 1767 | } |
| 1768 | EXPORT_SYMBOL(extent_invalidatepage); |
| 1769 | |
| 1770 | /* |
| 1771 | * simple commit_write call, set_range_dirty is used to mark both |
| 1772 | * the pages and the extent records as dirty |
| 1773 | */ |
| 1774 | int extent_commit_write(struct extent_map_tree *tree, |
| 1775 | struct inode *inode, struct page *page, |
| 1776 | unsigned from, unsigned to) |
| 1777 | { |
| 1778 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; |
| 1779 | |
Christoph Hellwig | b3cfa35 | 2007-09-17 11:25:58 -0400 | [diff] [blame] | 1780 | set_page_extent_mapped(page); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1781 | set_page_dirty(page); |
| 1782 | |
| 1783 | if (pos > inode->i_size) { |
| 1784 | i_size_write(inode, pos); |
| 1785 | mark_inode_dirty(inode); |
| 1786 | } |
| 1787 | return 0; |
| 1788 | } |
| 1789 | EXPORT_SYMBOL(extent_commit_write); |
| 1790 | |
| 1791 | int extent_prepare_write(struct extent_map_tree *tree, |
| 1792 | struct inode *inode, struct page *page, |
| 1793 | unsigned from, unsigned to, get_extent_t *get_extent) |
| 1794 | { |
| 1795 | u64 page_start = page->index << PAGE_CACHE_SHIFT; |
| 1796 | u64 page_end = page_start + PAGE_CACHE_SIZE - 1; |
| 1797 | u64 block_start; |
| 1798 | u64 orig_block_start; |
| 1799 | u64 block_end; |
| 1800 | u64 cur_end; |
| 1801 | struct extent_map *em; |
| 1802 | unsigned blocksize = 1 << inode->i_blkbits; |
| 1803 | size_t page_offset = 0; |
| 1804 | size_t block_off_start; |
| 1805 | size_t block_off_end; |
| 1806 | int err = 0; |
| 1807 | int iocount = 0; |
| 1808 | int ret = 0; |
| 1809 | int isnew; |
| 1810 | |
Christoph Hellwig | b3cfa35 | 2007-09-17 11:25:58 -0400 | [diff] [blame] | 1811 | set_page_extent_mapped(page); |
| 1812 | |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1813 | block_start = (page_start + from) & ~((u64)blocksize - 1); |
| 1814 | block_end = (page_start + to - 1) | (blocksize - 1); |
| 1815 | orig_block_start = block_start; |
| 1816 | |
| 1817 | lock_extent(tree, page_start, page_end, GFP_NOFS); |
| 1818 | while(block_start <= block_end) { |
| 1819 | em = get_extent(inode, page, page_offset, block_start, |
| 1820 | block_end, 1); |
| 1821 | if (IS_ERR(em) || !em) { |
| 1822 | goto err; |
| 1823 | } |
| 1824 | cur_end = min(block_end, em->end); |
| 1825 | block_off_start = block_start & (PAGE_CACHE_SIZE - 1); |
| 1826 | block_off_end = block_off_start + blocksize; |
| 1827 | isnew = clear_extent_new(tree, block_start, cur_end, GFP_NOFS); |
| 1828 | |
| 1829 | if (!PageUptodate(page) && isnew && |
| 1830 | (block_off_end > to || block_off_start < from)) { |
| 1831 | void *kaddr; |
| 1832 | |
| 1833 | kaddr = kmap_atomic(page, KM_USER0); |
| 1834 | if (block_off_end > to) |
| 1835 | memset(kaddr + to, 0, block_off_end - to); |
| 1836 | if (block_off_start < from) |
| 1837 | memset(kaddr + block_off_start, 0, |
| 1838 | from - block_off_start); |
| 1839 | flush_dcache_page(page); |
| 1840 | kunmap_atomic(kaddr, KM_USER0); |
| 1841 | } |
| 1842 | if (!isnew && !PageUptodate(page) && |
| 1843 | (block_off_end > to || block_off_start < from) && |
| 1844 | !test_range_bit(tree, block_start, cur_end, |
| 1845 | EXTENT_UPTODATE, 1)) { |
| 1846 | u64 sector; |
| 1847 | u64 extent_offset = block_start - em->start; |
| 1848 | size_t iosize; |
| 1849 | sector = (em->block_start + extent_offset) >> 9; |
| 1850 | iosize = (cur_end - block_start + blocksize - 1) & |
| 1851 | ~((u64)blocksize - 1); |
| 1852 | /* |
| 1853 | * we've already got the extent locked, but we |
| 1854 | * need to split the state such that our end_bio |
| 1855 | * handler can clear the lock. |
| 1856 | */ |
| 1857 | set_extent_bit(tree, block_start, |
| 1858 | block_start + iosize - 1, |
| 1859 | EXTENT_LOCKED, 0, NULL, GFP_NOFS); |
| 1860 | ret = submit_extent_page(READ, tree, page, |
| 1861 | sector, iosize, page_offset, em->bdev, |
| 1862 | end_bio_extent_preparewrite); |
| 1863 | iocount++; |
| 1864 | block_start = block_start + iosize; |
| 1865 | } else { |
| 1866 | set_extent_uptodate(tree, block_start, cur_end, |
| 1867 | GFP_NOFS); |
| 1868 | unlock_extent(tree, block_start, cur_end, GFP_NOFS); |
| 1869 | block_start = cur_end + 1; |
| 1870 | } |
| 1871 | page_offset = block_start & (PAGE_CACHE_SIZE - 1); |
| 1872 | free_extent_map(em); |
| 1873 | } |
| 1874 | if (iocount) { |
| 1875 | wait_extent_bit(tree, orig_block_start, |
| 1876 | block_end, EXTENT_LOCKED); |
| 1877 | } |
| 1878 | check_page_uptodate(tree, page); |
| 1879 | err: |
| 1880 | /* FIXME, zero out newly allocated blocks on error */ |
| 1881 | return err; |
| 1882 | } |
| 1883 | EXPORT_SYMBOL(extent_prepare_write); |
| 1884 | |
| 1885 | /* |
| 1886 | * a helper for releasepage. As long as there are no locked extents |
| 1887 | * in the range corresponding to the page, both state records and extent |
| 1888 | * map records are removed |
| 1889 | */ |
| 1890 | int try_release_extent_mapping(struct extent_map_tree *tree, struct page *page) |
| 1891 | { |
| 1892 | struct extent_map *em; |
| 1893 | u64 start = page->index << PAGE_CACHE_SHIFT; |
| 1894 | u64 end = start + PAGE_CACHE_SIZE - 1; |
| 1895 | u64 orig_start = start; |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1896 | int ret = 1; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1897 | |
| 1898 | while (start <= end) { |
| 1899 | em = lookup_extent_mapping(tree, start, end); |
| 1900 | if (!em || IS_ERR(em)) |
| 1901 | break; |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1902 | if (!test_range_bit(tree, em->start, em->end, |
| 1903 | EXTENT_LOCKED, 0)) { |
| 1904 | remove_extent_mapping(tree, em); |
| 1905 | /* once for the rb tree */ |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1906 | free_extent_map(em); |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1907 | } |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1908 | start = em->end + 1; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1909 | /* once for us */ |
| 1910 | free_extent_map(em); |
| 1911 | } |
Chris Mason | b888db2 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1912 | if (test_range_bit(tree, orig_start, end, EXTENT_LOCKED, 0)) |
| 1913 | ret = 0; |
| 1914 | else |
| 1915 | clear_extent_bit(tree, orig_start, end, EXTENT_UPTODATE, |
| 1916 | 1, 1, GFP_NOFS); |
| 1917 | return ret; |
Chris Mason | a52d9a8 | 2007-08-27 16:49:44 -0400 | [diff] [blame] | 1918 | } |
| 1919 | EXPORT_SYMBOL(try_release_extent_mapping); |
| 1920 | |
Christoph Hellwig | d396c6f | 2007-09-10 20:02:30 -0400 | [diff] [blame] | 1921 | sector_t extent_bmap(struct address_space *mapping, sector_t iblock, |
| 1922 | get_extent_t *get_extent) |
| 1923 | { |
| 1924 | struct inode *inode = mapping->host; |
| 1925 | u64 start = iblock << inode->i_blkbits; |
| 1926 | u64 end = start + (1 << inode->i_blkbits) - 1; |
| 1927 | struct extent_map *em; |
| 1928 | |
| 1929 | em = get_extent(inode, NULL, 0, start, end, 0); |
| 1930 | if (!em || IS_ERR(em)) |
| 1931 | return 0; |
| 1932 | |
Christoph Hellwig | d396c6f | 2007-09-10 20:02:30 -0400 | [diff] [blame] | 1933 | if (em->block_start == EXTENT_MAP_INLINE || |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1934 | em->block_start == EXTENT_MAP_HOLE) |
| 1935 | return 0; |
Christoph Hellwig | d396c6f | 2007-09-10 20:02:30 -0400 | [diff] [blame] | 1936 | |
| 1937 | return (em->block_start + start - em->start) >> inode->i_blkbits; |
| 1938 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 1939 | |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 1940 | static int add_lru(struct extent_map_tree *tree, struct extent_buffer *eb) |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 1941 | { |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 1942 | if (list_empty(&eb->lru)) { |
| 1943 | extent_buffer_get(eb); |
| 1944 | list_add(&eb->lru, &tree->buffer_lru); |
| 1945 | tree->lru_size++; |
| 1946 | if (tree->lru_size >= BUFFER_LRU_MAX) { |
| 1947 | struct extent_buffer *rm; |
| 1948 | rm = list_entry(tree->buffer_lru.prev, |
| 1949 | struct extent_buffer, lru); |
| 1950 | tree->lru_size--; |
| 1951 | list_del(&rm->lru); |
| 1952 | free_extent_buffer(rm); |
| 1953 | } |
| 1954 | } else |
| 1955 | list_move(&eb->lru, &tree->buffer_lru); |
| 1956 | return 0; |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 1957 | } |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 1958 | static struct extent_buffer *find_lru(struct extent_map_tree *tree, |
| 1959 | u64 start, unsigned long len) |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 1960 | { |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 1961 | struct list_head *lru = &tree->buffer_lru; |
| 1962 | struct list_head *cur = lru->next; |
| 1963 | struct extent_buffer *eb; |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 1964 | |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 1965 | if (list_empty(lru)) |
| 1966 | return NULL; |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 1967 | |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 1968 | do { |
| 1969 | eb = list_entry(cur, struct extent_buffer, lru); |
| 1970 | if (eb->start == start && eb->len == len) { |
| 1971 | extent_buffer_get(eb); |
| 1972 | return eb; |
| 1973 | } |
| 1974 | cur = cur->next; |
| 1975 | } while (cur != lru); |
| 1976 | return NULL; |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 1977 | } |
| 1978 | |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 1979 | static inline unsigned long num_extent_pages(u64 start, u64 len) |
| 1980 | { |
| 1981 | return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - |
| 1982 | (start >> PAGE_CACHE_SHIFT); |
| 1983 | } |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 1984 | |
| 1985 | static inline struct page *extent_buffer_page(struct extent_buffer *eb, |
| 1986 | unsigned long i) |
| 1987 | { |
| 1988 | struct page *p; |
| 1989 | |
| 1990 | if (i == 0) |
Chris Mason | 810191f | 2007-10-15 16:18:55 -0400 | [diff] [blame] | 1991 | return eb->first_page; |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 1992 | i += eb->start >> PAGE_CACHE_SHIFT; |
Chris Mason | 810191f | 2007-10-15 16:18:55 -0400 | [diff] [blame] | 1993 | p = find_get_page(eb->first_page->mapping, i); |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 1994 | page_cache_release(p); |
| 1995 | return p; |
| 1996 | } |
| 1997 | |
| 1998 | static struct extent_buffer *__alloc_extent_buffer(struct extent_map_tree *tree, |
| 1999 | u64 start, |
| 2000 | unsigned long len, |
| 2001 | gfp_t mask) |
| 2002 | { |
| 2003 | struct extent_buffer *eb = NULL; |
| 2004 | |
| 2005 | spin_lock(&tree->lru_lock); |
| 2006 | eb = find_lru(tree, start, len); |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2007 | if (eb) { |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 2008 | goto lru_add; |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2009 | } |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 2010 | spin_unlock(&tree->lru_lock); |
| 2011 | |
| 2012 | if (eb) { |
| 2013 | memset(eb, 0, sizeof(*eb)); |
| 2014 | } else { |
| 2015 | eb = kmem_cache_zalloc(extent_buffer_cache, mask); |
| 2016 | } |
| 2017 | INIT_LIST_HEAD(&eb->lru); |
| 2018 | eb->start = start; |
| 2019 | eb->len = len; |
| 2020 | atomic_set(&eb->refs, 1); |
| 2021 | |
| 2022 | spin_lock(&tree->lru_lock); |
| 2023 | lru_add: |
| 2024 | add_lru(tree, eb); |
| 2025 | spin_unlock(&tree->lru_lock); |
| 2026 | return eb; |
| 2027 | } |
| 2028 | |
| 2029 | static void __free_extent_buffer(struct extent_buffer *eb) |
| 2030 | { |
| 2031 | kmem_cache_free(extent_buffer_cache, eb); |
| 2032 | } |
| 2033 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2034 | struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree, |
| 2035 | u64 start, unsigned long len, |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2036 | struct page *page0, |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2037 | gfp_t mask) |
| 2038 | { |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2039 | unsigned long num_pages = num_extent_pages(start, len); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2040 | unsigned long i; |
| 2041 | unsigned long index = start >> PAGE_CACHE_SHIFT; |
| 2042 | struct extent_buffer *eb; |
| 2043 | struct page *p; |
| 2044 | struct address_space *mapping = tree->mapping; |
| 2045 | int uptodate = 0; |
| 2046 | |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 2047 | eb = __alloc_extent_buffer(tree, start, len, mask); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2048 | if (!eb || IS_ERR(eb)) |
| 2049 | return NULL; |
| 2050 | |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 2051 | if (eb->flags & EXTENT_BUFFER_FILLED) |
| 2052 | return eb; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2053 | |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2054 | if (page0) { |
| 2055 | eb->first_page = page0; |
| 2056 | i = 1; |
| 2057 | index++; |
| 2058 | page_cache_get(page0); |
Chris Mason | ff79f81 | 2007-10-15 16:22:25 -0400 | [diff] [blame] | 2059 | mark_page_accessed(page0); |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2060 | set_page_extent_mapped(page0); |
| 2061 | set_page_private(page0, EXTENT_PAGE_PRIVATE_FIRST_PAGE | |
| 2062 | len << 2); |
| 2063 | } else { |
| 2064 | i = 0; |
| 2065 | } |
| 2066 | for (; i < num_pages; i++, index++) { |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2067 | p = find_or_create_page(mapping, index, mask | __GFP_HIGHMEM); |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2068 | if (!p) { |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2069 | WARN_ON(1); |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2070 | /* make sure the free only frees the pages we've |
| 2071 | * grabbed a reference on |
| 2072 | */ |
| 2073 | eb->len = i << PAGE_CACHE_SHIFT; |
| 2074 | eb->start &= ~((u64)PAGE_CACHE_SIZE - 1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2075 | goto fail; |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2076 | } |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 2077 | set_page_extent_mapped(p); |
Chris Mason | ff79f81 | 2007-10-15 16:22:25 -0400 | [diff] [blame] | 2078 | mark_page_accessed(p); |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2079 | if (i == 0) { |
Chris Mason | 810191f | 2007-10-15 16:18:55 -0400 | [diff] [blame] | 2080 | eb->first_page = p; |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2081 | set_page_private(p, EXTENT_PAGE_PRIVATE_FIRST_PAGE | |
| 2082 | len << 2); |
| 2083 | } else { |
| 2084 | set_page_private(p, EXTENT_PAGE_PRIVATE); |
| 2085 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2086 | if (!PageUptodate(p)) |
| 2087 | uptodate = 0; |
| 2088 | unlock_page(p); |
| 2089 | } |
| 2090 | if (uptodate) |
| 2091 | eb->flags |= EXTENT_UPTODATE; |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 2092 | eb->flags |= EXTENT_BUFFER_FILLED; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2093 | return eb; |
| 2094 | fail: |
| 2095 | free_extent_buffer(eb); |
| 2096 | return NULL; |
| 2097 | } |
| 2098 | EXPORT_SYMBOL(alloc_extent_buffer); |
| 2099 | |
| 2100 | struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree, |
| 2101 | u64 start, unsigned long len, |
| 2102 | gfp_t mask) |
| 2103 | { |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2104 | unsigned long num_pages = num_extent_pages(start, len); |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2105 | unsigned long i; unsigned long index = start >> PAGE_CACHE_SHIFT; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2106 | struct extent_buffer *eb; |
| 2107 | struct page *p; |
| 2108 | struct address_space *mapping = tree->mapping; |
Chris Mason | 14048ed | 2007-10-15 16:16:28 -0400 | [diff] [blame] | 2109 | int uptodate = 1; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2110 | |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 2111 | eb = __alloc_extent_buffer(tree, start, len, mask); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2112 | if (!eb || IS_ERR(eb)) |
| 2113 | return NULL; |
| 2114 | |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 2115 | if (eb->flags & EXTENT_BUFFER_FILLED) |
| 2116 | return eb; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2117 | |
| 2118 | for (i = 0; i < num_pages; i++, index++) { |
Chris Mason | 14048ed | 2007-10-15 16:16:28 -0400 | [diff] [blame] | 2119 | p = find_lock_page(mapping, index); |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2120 | if (!p) { |
| 2121 | /* make sure the free only frees the pages we've |
| 2122 | * grabbed a reference on |
| 2123 | */ |
| 2124 | eb->len = i << PAGE_CACHE_SHIFT; |
| 2125 | eb->start &= ~((u64)PAGE_CACHE_SIZE - 1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2126 | goto fail; |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2127 | } |
Chris Mason | f510cfe | 2007-10-15 16:14:48 -0400 | [diff] [blame] | 2128 | set_page_extent_mapped(p); |
Chris Mason | ff79f81 | 2007-10-15 16:22:25 -0400 | [diff] [blame] | 2129 | mark_page_accessed(p); |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2130 | |
| 2131 | if (i == 0) { |
Chris Mason | 810191f | 2007-10-15 16:18:55 -0400 | [diff] [blame] | 2132 | eb->first_page = p; |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2133 | set_page_private(p, EXTENT_PAGE_PRIVATE_FIRST_PAGE | |
| 2134 | len << 2); |
| 2135 | } else { |
| 2136 | set_page_private(p, EXTENT_PAGE_PRIVATE); |
| 2137 | } |
| 2138 | |
Chris Mason | 14048ed | 2007-10-15 16:16:28 -0400 | [diff] [blame] | 2139 | if (!PageUptodate(p)) |
| 2140 | uptodate = 0; |
| 2141 | unlock_page(p); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2142 | } |
Chris Mason | 14048ed | 2007-10-15 16:16:28 -0400 | [diff] [blame] | 2143 | if (uptodate) |
| 2144 | eb->flags |= EXTENT_UPTODATE; |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 2145 | eb->flags |= EXTENT_BUFFER_FILLED; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2146 | return eb; |
| 2147 | fail: |
| 2148 | free_extent_buffer(eb); |
| 2149 | return NULL; |
| 2150 | } |
| 2151 | EXPORT_SYMBOL(find_extent_buffer); |
| 2152 | |
| 2153 | void free_extent_buffer(struct extent_buffer *eb) |
| 2154 | { |
| 2155 | unsigned long i; |
| 2156 | unsigned long num_pages; |
| 2157 | |
| 2158 | if (!eb) |
| 2159 | return; |
| 2160 | |
| 2161 | if (!atomic_dec_and_test(&eb->refs)) |
| 2162 | return; |
| 2163 | |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2164 | num_pages = num_extent_pages(eb->start, eb->len); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2165 | |
Chris Mason | 09e71a3 | 2007-10-15 16:17:04 -0400 | [diff] [blame] | 2166 | for (i = 0; i < num_pages; i++) { |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2167 | page_cache_release(extent_buffer_page(eb, i)); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2168 | } |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2169 | __free_extent_buffer(eb); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2170 | } |
| 2171 | EXPORT_SYMBOL(free_extent_buffer); |
| 2172 | |
| 2173 | int clear_extent_buffer_dirty(struct extent_map_tree *tree, |
| 2174 | struct extent_buffer *eb) |
| 2175 | { |
| 2176 | int set; |
| 2177 | unsigned long i; |
| 2178 | unsigned long num_pages; |
| 2179 | struct page *page; |
| 2180 | |
| 2181 | u64 start = eb->start; |
| 2182 | u64 end = start + eb->len - 1; |
| 2183 | |
| 2184 | set = clear_extent_dirty(tree, start, end, GFP_NOFS); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2185 | num_pages = num_extent_pages(eb->start, eb->len); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2186 | |
| 2187 | for (i = 0; i < num_pages; i++) { |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2188 | page = extent_buffer_page(eb, i); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2189 | lock_page(page); |
| 2190 | /* |
| 2191 | * if we're on the last page or the first page and the |
| 2192 | * block isn't aligned on a page boundary, do extra checks |
| 2193 | * to make sure we don't clean page that is partially dirty |
| 2194 | */ |
| 2195 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || |
| 2196 | ((i == num_pages - 1) && |
| 2197 | ((eb->start + eb->len - 1) & (PAGE_CACHE_SIZE - 1)))) { |
| 2198 | start = page->index << PAGE_CACHE_SHIFT; |
| 2199 | end = start + PAGE_CACHE_SIZE - 1; |
| 2200 | if (test_range_bit(tree, start, end, |
| 2201 | EXTENT_DIRTY, 0)) { |
| 2202 | unlock_page(page); |
| 2203 | continue; |
| 2204 | } |
| 2205 | } |
| 2206 | clear_page_dirty_for_io(page); |
| 2207 | unlock_page(page); |
| 2208 | } |
| 2209 | return 0; |
| 2210 | } |
| 2211 | EXPORT_SYMBOL(clear_extent_buffer_dirty); |
| 2212 | |
| 2213 | int wait_on_extent_buffer_writeback(struct extent_map_tree *tree, |
| 2214 | struct extent_buffer *eb) |
| 2215 | { |
| 2216 | return wait_on_extent_writeback(tree, eb->start, |
| 2217 | eb->start + eb->len - 1); |
| 2218 | } |
| 2219 | EXPORT_SYMBOL(wait_on_extent_buffer_writeback); |
| 2220 | |
| 2221 | int set_extent_buffer_dirty(struct extent_map_tree *tree, |
| 2222 | struct extent_buffer *eb) |
| 2223 | { |
Chris Mason | 810191f | 2007-10-15 16:18:55 -0400 | [diff] [blame] | 2224 | unsigned long i; |
| 2225 | unsigned long num_pages; |
| 2226 | |
| 2227 | num_pages = num_extent_pages(eb->start, eb->len); |
| 2228 | for (i = 0; i < num_pages; i++) { |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2229 | struct page *page = extent_buffer_page(eb, i); |
| 2230 | /* writepage may need to do something special for the |
| 2231 | * first page, we have to make sure page->private is |
| 2232 | * properly set. releasepage may drop page->private |
| 2233 | * on us if the page isn't already dirty. |
| 2234 | */ |
| 2235 | if (i == 0) { |
| 2236 | lock_page(page); |
| 2237 | set_page_private(page, |
| 2238 | EXTENT_PAGE_PRIVATE_FIRST_PAGE | |
| 2239 | eb->len << 2); |
| 2240 | } |
Chris Mason | 810191f | 2007-10-15 16:18:55 -0400 | [diff] [blame] | 2241 | __set_page_dirty_nobuffers(extent_buffer_page(eb, i)); |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2242 | if (i == 0) |
| 2243 | unlock_page(page); |
Chris Mason | 810191f | 2007-10-15 16:18:55 -0400 | [diff] [blame] | 2244 | } |
| 2245 | return set_extent_dirty(tree, eb->start, |
| 2246 | eb->start + eb->len - 1, GFP_NOFS); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2247 | } |
| 2248 | EXPORT_SYMBOL(set_extent_buffer_dirty); |
| 2249 | |
| 2250 | int set_extent_buffer_uptodate(struct extent_map_tree *tree, |
| 2251 | struct extent_buffer *eb) |
| 2252 | { |
| 2253 | unsigned long i; |
| 2254 | struct page *page; |
| 2255 | unsigned long num_pages; |
| 2256 | |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2257 | num_pages = num_extent_pages(eb->start, eb->len); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2258 | |
| 2259 | set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1, |
| 2260 | GFP_NOFS); |
| 2261 | for (i = 0; i < num_pages; i++) { |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2262 | page = extent_buffer_page(eb, i); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2263 | if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || |
| 2264 | ((i == num_pages - 1) && |
| 2265 | ((eb->start + eb->len - 1) & (PAGE_CACHE_SIZE - 1)))) { |
| 2266 | check_page_uptodate(tree, page); |
| 2267 | continue; |
| 2268 | } |
| 2269 | SetPageUptodate(page); |
| 2270 | } |
| 2271 | return 0; |
| 2272 | } |
| 2273 | EXPORT_SYMBOL(set_extent_buffer_uptodate); |
| 2274 | |
| 2275 | int extent_buffer_uptodate(struct extent_map_tree *tree, |
| 2276 | struct extent_buffer *eb) |
| 2277 | { |
| 2278 | if (eb->flags & EXTENT_UPTODATE) |
| 2279 | return 1; |
| 2280 | return test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
| 2281 | EXTENT_UPTODATE, 1); |
| 2282 | } |
| 2283 | EXPORT_SYMBOL(extent_buffer_uptodate); |
| 2284 | |
| 2285 | int read_extent_buffer_pages(struct extent_map_tree *tree, |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2286 | struct extent_buffer *eb, |
| 2287 | u64 start, |
| 2288 | int wait) |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2289 | { |
| 2290 | unsigned long i; |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2291 | unsigned long start_i; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2292 | struct page *page; |
| 2293 | int err; |
| 2294 | int ret = 0; |
| 2295 | unsigned long num_pages; |
| 2296 | |
| 2297 | if (eb->flags & EXTENT_UPTODATE) |
| 2298 | return 0; |
| 2299 | |
Chris Mason | 14048ed | 2007-10-15 16:16:28 -0400 | [diff] [blame] | 2300 | if (0 && test_range_bit(tree, eb->start, eb->start + eb->len - 1, |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2301 | EXTENT_UPTODATE, 1)) { |
| 2302 | return 0; |
| 2303 | } |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2304 | if (start) { |
| 2305 | WARN_ON(start < eb->start); |
| 2306 | start_i = (start >> PAGE_CACHE_SHIFT) - |
| 2307 | (eb->start >> PAGE_CACHE_SHIFT); |
| 2308 | } else { |
| 2309 | start_i = 0; |
| 2310 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2311 | |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2312 | num_pages = num_extent_pages(eb->start, eb->len); |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2313 | for (i = start_i; i < num_pages; i++) { |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2314 | page = extent_buffer_page(eb, i); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2315 | if (PageUptodate(page)) { |
| 2316 | continue; |
| 2317 | } |
| 2318 | if (!wait) { |
| 2319 | if (TestSetPageLocked(page)) { |
| 2320 | continue; |
| 2321 | } |
| 2322 | } else { |
| 2323 | lock_page(page); |
| 2324 | } |
| 2325 | if (!PageUptodate(page)) { |
| 2326 | err = page->mapping->a_ops->readpage(NULL, page); |
| 2327 | if (err) { |
| 2328 | ret = err; |
| 2329 | } |
| 2330 | } else { |
| 2331 | unlock_page(page); |
| 2332 | } |
| 2333 | } |
| 2334 | |
| 2335 | if (ret || !wait) { |
| 2336 | return ret; |
| 2337 | } |
| 2338 | |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2339 | for (i = start_i; i < num_pages; i++) { |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2340 | page = extent_buffer_page(eb, i); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2341 | wait_on_page_locked(page); |
| 2342 | if (!PageUptodate(page)) { |
| 2343 | ret = -EIO; |
| 2344 | } |
| 2345 | } |
Chris Mason | 4dc1190 | 2007-10-15 16:18:14 -0400 | [diff] [blame] | 2346 | if (!ret) |
| 2347 | eb->flags |= EXTENT_UPTODATE; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2348 | return ret; |
| 2349 | } |
| 2350 | EXPORT_SYMBOL(read_extent_buffer_pages); |
| 2351 | |
| 2352 | void read_extent_buffer(struct extent_buffer *eb, void *dstv, |
| 2353 | unsigned long start, |
| 2354 | unsigned long len) |
| 2355 | { |
| 2356 | size_t cur; |
| 2357 | size_t offset; |
| 2358 | struct page *page; |
| 2359 | char *kaddr; |
| 2360 | char *dst = (char *)dstv; |
| 2361 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); |
| 2362 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; |
Chris Mason | 14048ed | 2007-10-15 16:16:28 -0400 | [diff] [blame] | 2363 | unsigned long num_pages = num_extent_pages(eb->start, eb->len); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2364 | |
| 2365 | WARN_ON(start > eb->len); |
| 2366 | WARN_ON(start + len > eb->start + eb->len); |
| 2367 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2368 | offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); |
| 2369 | if (i == 0) |
| 2370 | offset += start_offset; |
| 2371 | |
| 2372 | while(len > 0) { |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2373 | page = extent_buffer_page(eb, i); |
Chris Mason | 14048ed | 2007-10-15 16:16:28 -0400 | [diff] [blame] | 2374 | if (!PageUptodate(page)) { |
| 2375 | printk("page %lu not up to date i %lu, total %lu, len %lu\n", page->index, i, num_pages, eb->len); |
| 2376 | WARN_ON(1); |
| 2377 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2378 | WARN_ON(!PageUptodate(page)); |
| 2379 | |
| 2380 | cur = min(len, (PAGE_CACHE_SIZE - offset)); |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2381 | kaddr = kmap_atomic(page, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2382 | memcpy(dst, kaddr + offset, cur); |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2383 | kunmap_atomic(kaddr, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2384 | |
| 2385 | dst += cur; |
| 2386 | len -= cur; |
| 2387 | offset = 0; |
| 2388 | i++; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2389 | } |
| 2390 | } |
| 2391 | EXPORT_SYMBOL(read_extent_buffer); |
| 2392 | |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2393 | int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2394 | unsigned long min_len, char **token, char **map, |
| 2395 | unsigned long *map_start, |
| 2396 | unsigned long *map_len, int km) |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2397 | { |
Chris Mason | 479965d | 2007-10-15 16:14:27 -0400 | [diff] [blame] | 2398 | size_t offset = start & (PAGE_CACHE_SIZE - 1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2399 | char *kaddr; |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2400 | struct page *p; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2401 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); |
| 2402 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; |
Chris Mason | 479965d | 2007-10-15 16:14:27 -0400 | [diff] [blame] | 2403 | unsigned long end_i = (start_offset + start + min_len) >> |
Chris Mason | 810191f | 2007-10-15 16:18:55 -0400 | [diff] [blame] | 2404 | PAGE_CACHE_SHIFT; |
Chris Mason | 479965d | 2007-10-15 16:14:27 -0400 | [diff] [blame] | 2405 | |
| 2406 | if (i != end_i) |
| 2407 | return -EINVAL; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2408 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2409 | if (i == 0) { |
| 2410 | offset = start_offset; |
| 2411 | *map_start = 0; |
| 2412 | } else { |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2413 | offset = 0; |
Chris Mason | 479965d | 2007-10-15 16:14:27 -0400 | [diff] [blame] | 2414 | *map_start = (i << PAGE_CACHE_SHIFT) - start_offset; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2415 | } |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2416 | if (start + min_len >= eb->len) { |
| 2417 | printk("bad mapping eb start %Lu len %lu, wanted %lu %lu\n", eb->start, eb->len, start, min_len); |
| 2418 | WARN_ON(1); |
| 2419 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2420 | |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2421 | p = extent_buffer_page(eb, i); |
| 2422 | WARN_ON(!PageUptodate(p)); |
| 2423 | kaddr = kmap_atomic(p, km); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2424 | *token = kaddr; |
| 2425 | *map = kaddr + offset; |
| 2426 | *map_len = PAGE_CACHE_SIZE - offset; |
| 2427 | return 0; |
| 2428 | } |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2429 | EXPORT_SYMBOL(map_private_extent_buffer); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2430 | |
| 2431 | int map_extent_buffer(struct extent_buffer *eb, unsigned long start, |
| 2432 | unsigned long min_len, |
| 2433 | char **token, char **map, |
| 2434 | unsigned long *map_start, |
| 2435 | unsigned long *map_len, int km) |
| 2436 | { |
| 2437 | int err; |
| 2438 | int save = 0; |
| 2439 | if (eb->map_token) { |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2440 | unmap_extent_buffer(eb, eb->map_token, km); |
| 2441 | eb->map_token = NULL; |
| 2442 | save = 1; |
| 2443 | } |
Chris Mason | 19c00dd | 2007-10-15 16:19:22 -0400 | [diff] [blame] | 2444 | err = map_private_extent_buffer(eb, start, min_len, token, map, |
| 2445 | map_start, map_len, km); |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2446 | if (!err && save) { |
| 2447 | eb->map_token = *token; |
| 2448 | eb->kaddr = *map; |
| 2449 | eb->map_start = *map_start; |
| 2450 | eb->map_len = *map_len; |
| 2451 | } |
| 2452 | return err; |
| 2453 | } |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2454 | EXPORT_SYMBOL(map_extent_buffer); |
| 2455 | |
| 2456 | void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) |
| 2457 | { |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2458 | kunmap_atomic(token, km); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2459 | } |
| 2460 | EXPORT_SYMBOL(unmap_extent_buffer); |
| 2461 | |
| 2462 | int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, |
| 2463 | unsigned long start, |
| 2464 | unsigned long len) |
| 2465 | { |
| 2466 | size_t cur; |
| 2467 | size_t offset; |
| 2468 | struct page *page; |
| 2469 | char *kaddr; |
| 2470 | char *ptr = (char *)ptrv; |
| 2471 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); |
| 2472 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; |
| 2473 | int ret = 0; |
| 2474 | |
| 2475 | WARN_ON(start > eb->len); |
| 2476 | WARN_ON(start + len > eb->start + eb->len); |
| 2477 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2478 | offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); |
| 2479 | if (i == 0) |
| 2480 | offset += start_offset; |
| 2481 | |
| 2482 | while(len > 0) { |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2483 | page = extent_buffer_page(eb, i); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2484 | WARN_ON(!PageUptodate(page)); |
| 2485 | |
| 2486 | cur = min(len, (PAGE_CACHE_SIZE - offset)); |
| 2487 | |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2488 | kaddr = kmap_atomic(page, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2489 | ret = memcmp(ptr, kaddr + offset, cur); |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2490 | kunmap_atomic(kaddr, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2491 | if (ret) |
| 2492 | break; |
| 2493 | |
| 2494 | ptr += cur; |
| 2495 | len -= cur; |
| 2496 | offset = 0; |
| 2497 | i++; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2498 | } |
| 2499 | return ret; |
| 2500 | } |
| 2501 | EXPORT_SYMBOL(memcmp_extent_buffer); |
| 2502 | |
| 2503 | void write_extent_buffer(struct extent_buffer *eb, const void *srcv, |
| 2504 | unsigned long start, unsigned long len) |
| 2505 | { |
| 2506 | size_t cur; |
| 2507 | size_t offset; |
| 2508 | struct page *page; |
| 2509 | char *kaddr; |
| 2510 | char *src = (char *)srcv; |
| 2511 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); |
| 2512 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; |
| 2513 | |
| 2514 | WARN_ON(start > eb->len); |
| 2515 | WARN_ON(start + len > eb->start + eb->len); |
| 2516 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2517 | offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); |
| 2518 | if (i == 0) |
| 2519 | offset += start_offset; |
| 2520 | |
| 2521 | while(len > 0) { |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2522 | page = extent_buffer_page(eb, i); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2523 | WARN_ON(!PageUptodate(page)); |
| 2524 | |
| 2525 | cur = min(len, PAGE_CACHE_SIZE - offset); |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2526 | kaddr = kmap_atomic(page, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2527 | memcpy(kaddr + offset, src, cur); |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2528 | kunmap_atomic(kaddr, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2529 | |
| 2530 | src += cur; |
| 2531 | len -= cur; |
| 2532 | offset = 0; |
| 2533 | i++; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2534 | } |
| 2535 | } |
| 2536 | EXPORT_SYMBOL(write_extent_buffer); |
| 2537 | |
| 2538 | void memset_extent_buffer(struct extent_buffer *eb, char c, |
| 2539 | unsigned long start, unsigned long len) |
| 2540 | { |
| 2541 | size_t cur; |
| 2542 | size_t offset; |
| 2543 | struct page *page; |
| 2544 | char *kaddr; |
| 2545 | size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); |
| 2546 | unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; |
| 2547 | |
| 2548 | WARN_ON(start > eb->len); |
| 2549 | WARN_ON(start + len > eb->start + eb->len); |
| 2550 | |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2551 | offset = start & ((unsigned long)PAGE_CACHE_SIZE - 1); |
| 2552 | if (i == 0) |
| 2553 | offset += start_offset; |
| 2554 | |
| 2555 | while(len > 0) { |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2556 | page = extent_buffer_page(eb, i); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2557 | WARN_ON(!PageUptodate(page)); |
| 2558 | |
| 2559 | cur = min(len, PAGE_CACHE_SIZE - offset); |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2560 | kaddr = kmap_atomic(page, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2561 | memset(kaddr + offset, c, cur); |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2562 | kunmap_atomic(kaddr, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2563 | |
| 2564 | len -= cur; |
| 2565 | offset = 0; |
| 2566 | i++; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2567 | } |
| 2568 | } |
| 2569 | EXPORT_SYMBOL(memset_extent_buffer); |
| 2570 | |
| 2571 | void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, |
| 2572 | unsigned long dst_offset, unsigned long src_offset, |
| 2573 | unsigned long len) |
| 2574 | { |
| 2575 | u64 dst_len = dst->len; |
| 2576 | size_t cur; |
| 2577 | size_t offset; |
| 2578 | struct page *page; |
| 2579 | char *kaddr; |
| 2580 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); |
| 2581 | unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; |
| 2582 | |
| 2583 | WARN_ON(src->len != dst_len); |
| 2584 | |
| 2585 | offset = dst_offset & ((unsigned long)PAGE_CACHE_SIZE - 1); |
| 2586 | if (i == 0) |
| 2587 | offset += start_offset; |
| 2588 | |
| 2589 | while(len > 0) { |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2590 | page = extent_buffer_page(dst, i); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2591 | WARN_ON(!PageUptodate(page)); |
| 2592 | |
| 2593 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); |
| 2594 | |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2595 | kaddr = kmap_atomic(page, KM_USER1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2596 | read_extent_buffer(src, kaddr + offset, src_offset, cur); |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2597 | kunmap_atomic(kaddr, KM_USER1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2598 | |
| 2599 | src_offset += cur; |
| 2600 | len -= cur; |
| 2601 | offset = 0; |
| 2602 | i++; |
| 2603 | } |
| 2604 | } |
| 2605 | EXPORT_SYMBOL(copy_extent_buffer); |
| 2606 | |
| 2607 | static void move_pages(struct page *dst_page, struct page *src_page, |
| 2608 | unsigned long dst_off, unsigned long src_off, |
| 2609 | unsigned long len) |
| 2610 | { |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2611 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2612 | if (dst_page == src_page) { |
| 2613 | memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); |
| 2614 | } else { |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2615 | char *src_kaddr = kmap_atomic(src_page, KM_USER1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2616 | char *p = dst_kaddr + dst_off + len; |
| 2617 | char *s = src_kaddr + src_off + len; |
| 2618 | |
| 2619 | while (len--) |
| 2620 | *--p = *--s; |
| 2621 | |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2622 | kunmap_atomic(src_kaddr, KM_USER1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2623 | } |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2624 | kunmap_atomic(dst_kaddr, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2625 | } |
| 2626 | |
| 2627 | static void copy_pages(struct page *dst_page, struct page *src_page, |
| 2628 | unsigned long dst_off, unsigned long src_off, |
| 2629 | unsigned long len) |
| 2630 | { |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2631 | char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2632 | char *src_kaddr; |
| 2633 | |
| 2634 | if (dst_page != src_page) |
Chris Mason | ae5252b | 2007-10-15 16:14:41 -0400 | [diff] [blame] | 2635 | src_kaddr = kmap_atomic(src_page, KM_USER1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2636 | else |
| 2637 | src_kaddr = dst_kaddr; |
| 2638 | |
| 2639 | memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2640 | kunmap_atomic(dst_kaddr, KM_USER0); |
| 2641 | if (dst_page != src_page) |
| 2642 | kunmap_atomic(src_kaddr, KM_USER1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2643 | } |
| 2644 | |
| 2645 | void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, |
| 2646 | unsigned long src_offset, unsigned long len) |
| 2647 | { |
| 2648 | size_t cur; |
| 2649 | size_t dst_off_in_page; |
| 2650 | size_t src_off_in_page; |
| 2651 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); |
| 2652 | unsigned long dst_i; |
| 2653 | unsigned long src_i; |
| 2654 | |
| 2655 | if (src_offset + len > dst->len) { |
| 2656 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", |
| 2657 | src_offset, len, dst->len); |
| 2658 | BUG_ON(1); |
| 2659 | } |
| 2660 | if (dst_offset + len > dst->len) { |
| 2661 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", |
| 2662 | dst_offset, len, dst->len); |
| 2663 | BUG_ON(1); |
| 2664 | } |
| 2665 | |
| 2666 | while(len > 0) { |
| 2667 | dst_off_in_page = dst_offset & |
| 2668 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
| 2669 | src_off_in_page = src_offset & |
| 2670 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
| 2671 | |
| 2672 | dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT; |
| 2673 | src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT; |
| 2674 | |
| 2675 | if (src_i == 0) |
| 2676 | src_off_in_page += start_offset; |
| 2677 | if (dst_i == 0) |
| 2678 | dst_off_in_page += start_offset; |
| 2679 | |
| 2680 | cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - |
| 2681 | src_off_in_page)); |
Jens Axboe | ae2f541 | 2007-10-19 09:22:59 -0400 | [diff] [blame] | 2682 | cur = min_t(unsigned long, cur, |
| 2683 | (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page)); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2684 | |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2685 | copy_pages(extent_buffer_page(dst, dst_i), |
| 2686 | extent_buffer_page(dst, src_i), |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2687 | dst_off_in_page, src_off_in_page, cur); |
| 2688 | |
| 2689 | src_offset += cur; |
| 2690 | dst_offset += cur; |
| 2691 | len -= cur; |
| 2692 | } |
| 2693 | } |
| 2694 | EXPORT_SYMBOL(memcpy_extent_buffer); |
| 2695 | |
| 2696 | void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, |
| 2697 | unsigned long src_offset, unsigned long len) |
| 2698 | { |
| 2699 | size_t cur; |
| 2700 | size_t dst_off_in_page; |
| 2701 | size_t src_off_in_page; |
| 2702 | unsigned long dst_end = dst_offset + len - 1; |
| 2703 | unsigned long src_end = src_offset + len - 1; |
| 2704 | size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1); |
| 2705 | unsigned long dst_i; |
| 2706 | unsigned long src_i; |
| 2707 | |
| 2708 | if (src_offset + len > dst->len) { |
| 2709 | printk("memmove bogus src_offset %lu move len %lu len %lu\n", |
| 2710 | src_offset, len, dst->len); |
| 2711 | BUG_ON(1); |
| 2712 | } |
| 2713 | if (dst_offset + len > dst->len) { |
| 2714 | printk("memmove bogus dst_offset %lu move len %lu len %lu\n", |
| 2715 | dst_offset, len, dst->len); |
| 2716 | BUG_ON(1); |
| 2717 | } |
| 2718 | if (dst_offset < src_offset) { |
| 2719 | memcpy_extent_buffer(dst, dst_offset, src_offset, len); |
| 2720 | return; |
| 2721 | } |
| 2722 | while(len > 0) { |
| 2723 | dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT; |
| 2724 | src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT; |
| 2725 | |
| 2726 | dst_off_in_page = dst_end & |
| 2727 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
| 2728 | src_off_in_page = src_end & |
| 2729 | ((unsigned long)PAGE_CACHE_SIZE - 1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2730 | if (src_i == 0) |
| 2731 | src_off_in_page += start_offset; |
| 2732 | if (dst_i == 0) |
| 2733 | dst_off_in_page += start_offset; |
| 2734 | |
Jens Axboe | ae2f541 | 2007-10-19 09:22:59 -0400 | [diff] [blame] | 2735 | cur = min_t(unsigned long, len, src_off_in_page + 1); |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2736 | cur = min(cur, dst_off_in_page + 1); |
Chris Mason | 6d36dcd | 2007-10-15 16:14:37 -0400 | [diff] [blame] | 2737 | move_pages(extent_buffer_page(dst, dst_i), |
| 2738 | extent_buffer_page(dst, src_i), |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2739 | dst_off_in_page - cur + 1, |
| 2740 | src_off_in_page - cur + 1, cur); |
| 2741 | |
Chris Mason | db94535 | 2007-10-15 16:15:53 -0400 | [diff] [blame] | 2742 | dst_end -= cur; |
| 2743 | src_end -= cur; |
Chris Mason | 5f39d39 | 2007-10-15 16:14:19 -0400 | [diff] [blame] | 2744 | len -= cur; |
| 2745 | } |
| 2746 | } |
| 2747 | EXPORT_SYMBOL(memmove_extent_buffer); |