Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2011 Red Hat, Inc. |
| 3 | * |
| 4 | * This file is released under the GPL. |
| 5 | */ |
| 6 | |
| 7 | #include "dm-space-map.h" |
| 8 | #include "dm-space-map-common.h" |
| 9 | #include "dm-space-map-metadata.h" |
| 10 | |
| 11 | #include <linux/list.h> |
| 12 | #include <linux/slab.h> |
| 13 | #include <linux/device-mapper.h> |
| 14 | |
| 15 | #define DM_MSG_PREFIX "space map metadata" |
| 16 | |
| 17 | /*----------------------------------------------------------------*/ |
| 18 | |
| 19 | /* |
Joe Thornber | 2fc4802 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 20 | * An edge triggered threshold. |
| 21 | */ |
| 22 | struct threshold { |
| 23 | bool threshold_set; |
| 24 | bool value_set; |
| 25 | dm_block_t threshold; |
| 26 | dm_block_t current_value; |
| 27 | dm_sm_threshold_fn fn; |
| 28 | void *context; |
| 29 | }; |
| 30 | |
| 31 | static void threshold_init(struct threshold *t) |
| 32 | { |
| 33 | t->threshold_set = false; |
| 34 | t->value_set = false; |
| 35 | } |
| 36 | |
| 37 | static void set_threshold(struct threshold *t, dm_block_t value, |
| 38 | dm_sm_threshold_fn fn, void *context) |
| 39 | { |
| 40 | t->threshold_set = true; |
| 41 | t->threshold = value; |
| 42 | t->fn = fn; |
| 43 | t->context = context; |
| 44 | } |
| 45 | |
| 46 | static bool below_threshold(struct threshold *t, dm_block_t value) |
| 47 | { |
| 48 | return t->threshold_set && value <= t->threshold; |
| 49 | } |
| 50 | |
| 51 | static bool threshold_already_triggered(struct threshold *t) |
| 52 | { |
| 53 | return t->value_set && below_threshold(t, t->current_value); |
| 54 | } |
| 55 | |
| 56 | static void check_threshold(struct threshold *t, dm_block_t value) |
| 57 | { |
| 58 | if (below_threshold(t, value) && |
| 59 | !threshold_already_triggered(t)) |
| 60 | t->fn(t->context); |
| 61 | |
| 62 | t->value_set = true; |
| 63 | t->current_value = value; |
| 64 | } |
| 65 | |
| 66 | /*----------------------------------------------------------------*/ |
| 67 | |
| 68 | /* |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 69 | * Space map interface. |
| 70 | * |
| 71 | * The low level disk format is written using the standard btree and |
| 72 | * transaction manager. This means that performing disk operations may |
| 73 | * cause us to recurse into the space map in order to allocate new blocks. |
| 74 | * For this reason we have a pool of pre-allocated blocks large enough to |
| 75 | * service any metadata_ll_disk operation. |
| 76 | */ |
| 77 | |
| 78 | /* |
| 79 | * FIXME: we should calculate this based on the size of the device. |
| 80 | * Only the metadata space map needs this functionality. |
| 81 | */ |
| 82 | #define MAX_RECURSIVE_ALLOCATIONS 1024 |
| 83 | |
| 84 | enum block_op_type { |
| 85 | BOP_INC, |
| 86 | BOP_DEC |
| 87 | }; |
| 88 | |
| 89 | struct block_op { |
| 90 | enum block_op_type type; |
| 91 | dm_block_t block; |
| 92 | }; |
| 93 | |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 94 | struct bop_ring_buffer { |
| 95 | unsigned begin; |
| 96 | unsigned end; |
| 97 | struct block_op bops[MAX_RECURSIVE_ALLOCATIONS + 1]; |
| 98 | }; |
| 99 | |
| 100 | static void brb_init(struct bop_ring_buffer *brb) |
| 101 | { |
| 102 | brb->begin = 0; |
| 103 | brb->end = 0; |
| 104 | } |
| 105 | |
| 106 | static bool brb_empty(struct bop_ring_buffer *brb) |
| 107 | { |
| 108 | return brb->begin == brb->end; |
| 109 | } |
| 110 | |
| 111 | static unsigned brb_next(struct bop_ring_buffer *brb, unsigned old) |
| 112 | { |
| 113 | unsigned r = old + 1; |
| 114 | return (r >= (sizeof(brb->bops) / sizeof(*brb->bops))) ? 0 : r; |
| 115 | } |
| 116 | |
| 117 | static int brb_push(struct bop_ring_buffer *brb, |
| 118 | enum block_op_type type, dm_block_t b) |
| 119 | { |
| 120 | struct block_op *bop; |
| 121 | unsigned next = brb_next(brb, brb->end); |
| 122 | |
| 123 | /* |
| 124 | * We don't allow the last bop to be filled, this way we can |
| 125 | * differentiate between full and empty. |
| 126 | */ |
| 127 | if (next == brb->begin) |
| 128 | return -ENOMEM; |
| 129 | |
| 130 | bop = brb->bops + brb->end; |
| 131 | bop->type = type; |
| 132 | bop->block = b; |
| 133 | |
| 134 | brb->end = next; |
| 135 | |
| 136 | return 0; |
| 137 | } |
| 138 | |
| 139 | static int brb_pop(struct bop_ring_buffer *brb, struct block_op *result) |
| 140 | { |
| 141 | struct block_op *bop; |
| 142 | |
| 143 | if (brb_empty(brb)) |
| 144 | return -ENODATA; |
| 145 | |
| 146 | bop = brb->bops + brb->begin; |
| 147 | result->type = bop->type; |
| 148 | result->block = bop->block; |
| 149 | |
| 150 | brb->begin = brb_next(brb, brb->begin); |
| 151 | |
| 152 | return 0; |
| 153 | } |
| 154 | |
| 155 | /*----------------------------------------------------------------*/ |
| 156 | |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 157 | struct sm_metadata { |
| 158 | struct dm_space_map sm; |
| 159 | |
| 160 | struct ll_disk ll; |
| 161 | struct ll_disk old_ll; |
| 162 | |
| 163 | dm_block_t begin; |
| 164 | |
| 165 | unsigned recursion_count; |
| 166 | unsigned allocated_this_transaction; |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 167 | struct bop_ring_buffer uncommitted; |
Joe Thornber | 2fc4802 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 168 | |
| 169 | struct threshold threshold; |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 170 | }; |
| 171 | |
| 172 | static int add_bop(struct sm_metadata *smm, enum block_op_type type, dm_block_t b) |
| 173 | { |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 174 | int r = brb_push(&smm->uncommitted, type, b); |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 175 | |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 176 | if (r) { |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 177 | DMERR("too many recursive allocations"); |
| 178 | return -ENOMEM; |
| 179 | } |
| 180 | |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 181 | return 0; |
| 182 | } |
| 183 | |
| 184 | static int commit_bop(struct sm_metadata *smm, struct block_op *op) |
| 185 | { |
| 186 | int r = 0; |
| 187 | enum allocation_event ev; |
| 188 | |
| 189 | switch (op->type) { |
| 190 | case BOP_INC: |
| 191 | r = sm_ll_inc(&smm->ll, op->block, &ev); |
| 192 | break; |
| 193 | |
| 194 | case BOP_DEC: |
| 195 | r = sm_ll_dec(&smm->ll, op->block, &ev); |
| 196 | break; |
| 197 | } |
| 198 | |
| 199 | return r; |
| 200 | } |
| 201 | |
| 202 | static void in(struct sm_metadata *smm) |
| 203 | { |
| 204 | smm->recursion_count++; |
| 205 | } |
| 206 | |
| 207 | static int out(struct sm_metadata *smm) |
| 208 | { |
| 209 | int r = 0; |
| 210 | |
| 211 | /* |
| 212 | * If we're not recursing then very bad things are happening. |
| 213 | */ |
| 214 | if (!smm->recursion_count) { |
| 215 | DMERR("lost track of recursion depth"); |
| 216 | return -ENOMEM; |
| 217 | } |
| 218 | |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 219 | if (smm->recursion_count == 1) { |
| 220 | while (!brb_empty(&smm->uncommitted)) { |
| 221 | struct block_op bop; |
| 222 | |
| 223 | r = brb_pop(&smm->uncommitted, &bop); |
| 224 | if (r) { |
| 225 | DMERR("bug in bop ring buffer"); |
| 226 | break; |
| 227 | } |
| 228 | |
| 229 | r = commit_bop(smm, &bop); |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 230 | if (r) |
| 231 | break; |
| 232 | } |
| 233 | } |
| 234 | |
| 235 | smm->recursion_count--; |
| 236 | |
| 237 | return r; |
| 238 | } |
| 239 | |
| 240 | /* |
| 241 | * When using the out() function above, we often want to combine an error |
| 242 | * code for the operation run in the recursive context with that from |
| 243 | * out(). |
| 244 | */ |
| 245 | static int combine_errors(int r1, int r2) |
| 246 | { |
| 247 | return r1 ? r1 : r2; |
| 248 | } |
| 249 | |
| 250 | static int recursing(struct sm_metadata *smm) |
| 251 | { |
| 252 | return smm->recursion_count; |
| 253 | } |
| 254 | |
| 255 | static void sm_metadata_destroy(struct dm_space_map *sm) |
| 256 | { |
| 257 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 258 | |
| 259 | kfree(smm); |
| 260 | } |
| 261 | |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 262 | static int sm_metadata_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count) |
| 263 | { |
| 264 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 265 | |
| 266 | *count = smm->ll.nr_blocks; |
| 267 | |
| 268 | return 0; |
| 269 | } |
| 270 | |
| 271 | static int sm_metadata_get_nr_free(struct dm_space_map *sm, dm_block_t *count) |
| 272 | { |
| 273 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 274 | |
| 275 | *count = smm->old_ll.nr_blocks - smm->old_ll.nr_allocated - |
| 276 | smm->allocated_this_transaction; |
| 277 | |
| 278 | return 0; |
| 279 | } |
| 280 | |
| 281 | static int sm_metadata_get_count(struct dm_space_map *sm, dm_block_t b, |
| 282 | uint32_t *result) |
| 283 | { |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 284 | int r; |
| 285 | unsigned i; |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 286 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 287 | unsigned adjustment = 0; |
| 288 | |
| 289 | /* |
| 290 | * We may have some uncommitted adjustments to add. This list |
| 291 | * should always be really short. |
| 292 | */ |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 293 | for (i = smm->uncommitted.begin; |
| 294 | i != smm->uncommitted.end; |
| 295 | i = brb_next(&smm->uncommitted, i)) { |
| 296 | struct block_op *op = smm->uncommitted.bops + i; |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 297 | |
| 298 | if (op->block != b) |
| 299 | continue; |
| 300 | |
| 301 | switch (op->type) { |
| 302 | case BOP_INC: |
| 303 | adjustment++; |
| 304 | break; |
| 305 | |
| 306 | case BOP_DEC: |
| 307 | adjustment--; |
| 308 | break; |
| 309 | } |
| 310 | } |
| 311 | |
| 312 | r = sm_ll_lookup(&smm->ll, b, result); |
| 313 | if (r) |
| 314 | return r; |
| 315 | |
| 316 | *result += adjustment; |
| 317 | |
| 318 | return 0; |
| 319 | } |
| 320 | |
| 321 | static int sm_metadata_count_is_more_than_one(struct dm_space_map *sm, |
| 322 | dm_block_t b, int *result) |
| 323 | { |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 324 | int r, adjustment = 0; |
| 325 | unsigned i; |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 326 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 327 | uint32_t rc; |
| 328 | |
| 329 | /* |
| 330 | * We may have some uncommitted adjustments to add. This list |
| 331 | * should always be really short. |
| 332 | */ |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 333 | for (i = smm->uncommitted.begin; |
| 334 | i != smm->uncommitted.end; |
| 335 | i = brb_next(&smm->uncommitted, i)) { |
| 336 | |
| 337 | struct block_op *op = smm->uncommitted.bops + i; |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 338 | |
| 339 | if (op->block != b) |
| 340 | continue; |
| 341 | |
| 342 | switch (op->type) { |
| 343 | case BOP_INC: |
| 344 | adjustment++; |
| 345 | break; |
| 346 | |
| 347 | case BOP_DEC: |
| 348 | adjustment--; |
| 349 | break; |
| 350 | } |
| 351 | } |
| 352 | |
| 353 | if (adjustment > 1) { |
| 354 | *result = 1; |
| 355 | return 0; |
| 356 | } |
| 357 | |
| 358 | r = sm_ll_lookup_bitmap(&smm->ll, b, &rc); |
| 359 | if (r) |
| 360 | return r; |
| 361 | |
| 362 | if (rc == 3) |
| 363 | /* |
| 364 | * We err on the side of caution, and always return true. |
| 365 | */ |
| 366 | *result = 1; |
| 367 | else |
| 368 | *result = rc + adjustment > 1; |
| 369 | |
| 370 | return 0; |
| 371 | } |
| 372 | |
| 373 | static int sm_metadata_set_count(struct dm_space_map *sm, dm_block_t b, |
| 374 | uint32_t count) |
| 375 | { |
| 376 | int r, r2; |
| 377 | enum allocation_event ev; |
| 378 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 379 | |
| 380 | if (smm->recursion_count) { |
| 381 | DMERR("cannot recurse set_count()"); |
| 382 | return -EINVAL; |
| 383 | } |
| 384 | |
| 385 | in(smm); |
| 386 | r = sm_ll_insert(&smm->ll, b, count, &ev); |
| 387 | r2 = out(smm); |
| 388 | |
| 389 | return combine_errors(r, r2); |
| 390 | } |
| 391 | |
| 392 | static int sm_metadata_inc_block(struct dm_space_map *sm, dm_block_t b) |
| 393 | { |
| 394 | int r, r2 = 0; |
| 395 | enum allocation_event ev; |
| 396 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 397 | |
| 398 | if (recursing(smm)) |
| 399 | r = add_bop(smm, BOP_INC, b); |
| 400 | else { |
| 401 | in(smm); |
| 402 | r = sm_ll_inc(&smm->ll, b, &ev); |
| 403 | r2 = out(smm); |
| 404 | } |
| 405 | |
| 406 | return combine_errors(r, r2); |
| 407 | } |
| 408 | |
| 409 | static int sm_metadata_dec_block(struct dm_space_map *sm, dm_block_t b) |
| 410 | { |
| 411 | int r, r2 = 0; |
| 412 | enum allocation_event ev; |
| 413 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 414 | |
| 415 | if (recursing(smm)) |
| 416 | r = add_bop(smm, BOP_DEC, b); |
| 417 | else { |
| 418 | in(smm); |
| 419 | r = sm_ll_dec(&smm->ll, b, &ev); |
| 420 | r2 = out(smm); |
| 421 | } |
| 422 | |
| 423 | return combine_errors(r, r2); |
| 424 | } |
| 425 | |
| 426 | static int sm_metadata_new_block_(struct dm_space_map *sm, dm_block_t *b) |
| 427 | { |
| 428 | int r, r2 = 0; |
| 429 | enum allocation_event ev; |
| 430 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 431 | |
| 432 | r = sm_ll_find_free_block(&smm->old_ll, smm->begin, smm->old_ll.nr_blocks, b); |
| 433 | if (r) |
| 434 | return r; |
| 435 | |
| 436 | smm->begin = *b + 1; |
| 437 | |
| 438 | if (recursing(smm)) |
| 439 | r = add_bop(smm, BOP_INC, *b); |
| 440 | else { |
| 441 | in(smm); |
| 442 | r = sm_ll_inc(&smm->ll, *b, &ev); |
| 443 | r2 = out(smm); |
| 444 | } |
| 445 | |
| 446 | if (!r) |
| 447 | smm->allocated_this_transaction++; |
| 448 | |
| 449 | return combine_errors(r, r2); |
| 450 | } |
| 451 | |
| 452 | static int sm_metadata_new_block(struct dm_space_map *sm, dm_block_t *b) |
| 453 | { |
Joe Thornber | 2fc4802 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 454 | dm_block_t count; |
| 455 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 456 | |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 457 | int r = sm_metadata_new_block_(sm, b); |
Mike Snitzer | f62b6b8 | 2013-12-02 16:47:01 -0500 | [diff] [blame] | 458 | if (r) { |
Mike Snitzer | c46985e | 2013-12-13 09:58:46 -0500 | [diff] [blame] | 459 | DMERR_LIMIT("unable to allocate new metadata block"); |
Mike Snitzer | f62b6b8 | 2013-12-02 16:47:01 -0500 | [diff] [blame] | 460 | return r; |
| 461 | } |
Joe Thornber | 2fc4802 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 462 | |
| 463 | r = sm_metadata_get_nr_free(sm, &count); |
Mike Snitzer | f62b6b8 | 2013-12-02 16:47:01 -0500 | [diff] [blame] | 464 | if (r) { |
Mike Snitzer | c46985e | 2013-12-13 09:58:46 -0500 | [diff] [blame] | 465 | DMERR_LIMIT("couldn't get free block count"); |
Mike Snitzer | f62b6b8 | 2013-12-02 16:47:01 -0500 | [diff] [blame] | 466 | return r; |
| 467 | } |
Joe Thornber | 2fc4802 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 468 | |
| 469 | check_threshold(&smm->threshold, count); |
| 470 | |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 471 | return r; |
| 472 | } |
| 473 | |
| 474 | static int sm_metadata_commit(struct dm_space_map *sm) |
| 475 | { |
| 476 | int r; |
| 477 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 478 | |
| 479 | r = sm_ll_commit(&smm->ll); |
| 480 | if (r) |
| 481 | return r; |
| 482 | |
| 483 | memcpy(&smm->old_ll, &smm->ll, sizeof(smm->old_ll)); |
| 484 | smm->begin = 0; |
| 485 | smm->allocated_this_transaction = 0; |
| 486 | |
| 487 | return 0; |
| 488 | } |
| 489 | |
Joe Thornber | 2fc4802 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 490 | static int sm_metadata_register_threshold_callback(struct dm_space_map *sm, |
| 491 | dm_block_t threshold, |
| 492 | dm_sm_threshold_fn fn, |
| 493 | void *context) |
| 494 | { |
| 495 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 496 | |
| 497 | set_threshold(&smm->threshold, threshold, fn, context); |
| 498 | |
| 499 | return 0; |
| 500 | } |
| 501 | |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 502 | static int sm_metadata_root_size(struct dm_space_map *sm, size_t *result) |
| 503 | { |
| 504 | *result = sizeof(struct disk_sm_root); |
| 505 | |
| 506 | return 0; |
| 507 | } |
| 508 | |
| 509 | static int sm_metadata_copy_root(struct dm_space_map *sm, void *where_le, size_t max) |
| 510 | { |
| 511 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 512 | struct disk_sm_root root_le; |
| 513 | |
| 514 | root_le.nr_blocks = cpu_to_le64(smm->ll.nr_blocks); |
| 515 | root_le.nr_allocated = cpu_to_le64(smm->ll.nr_allocated); |
| 516 | root_le.bitmap_root = cpu_to_le64(smm->ll.bitmap_root); |
| 517 | root_le.ref_count_root = cpu_to_le64(smm->ll.ref_count_root); |
| 518 | |
| 519 | if (max < sizeof(root_le)) |
| 520 | return -ENOSPC; |
| 521 | |
| 522 | memcpy(where_le, &root_le, sizeof(root_le)); |
| 523 | |
| 524 | return 0; |
| 525 | } |
| 526 | |
Joe Thornber | 1921c56 | 2013-05-10 14:37:19 +0100 | [diff] [blame] | 527 | static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks); |
| 528 | |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 529 | static struct dm_space_map ops = { |
| 530 | .destroy = sm_metadata_destroy, |
| 531 | .extend = sm_metadata_extend, |
| 532 | .get_nr_blocks = sm_metadata_get_nr_blocks, |
| 533 | .get_nr_free = sm_metadata_get_nr_free, |
| 534 | .get_count = sm_metadata_get_count, |
| 535 | .count_is_more_than_one = sm_metadata_count_is_more_than_one, |
| 536 | .set_count = sm_metadata_set_count, |
| 537 | .inc_block = sm_metadata_inc_block, |
| 538 | .dec_block = sm_metadata_dec_block, |
| 539 | .new_block = sm_metadata_new_block, |
| 540 | .commit = sm_metadata_commit, |
| 541 | .root_size = sm_metadata_root_size, |
Joe Thornber | 7c3d3f2 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 542 | .copy_root = sm_metadata_copy_root, |
Joe Thornber | 2fc4802 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 543 | .register_threshold_callback = sm_metadata_register_threshold_callback |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 544 | }; |
| 545 | |
| 546 | /*----------------------------------------------------------------*/ |
| 547 | |
| 548 | /* |
| 549 | * When a new space map is created that manages its own space. We use |
| 550 | * this tiny bootstrap allocator. |
| 551 | */ |
| 552 | static void sm_bootstrap_destroy(struct dm_space_map *sm) |
| 553 | { |
| 554 | } |
| 555 | |
| 556 | static int sm_bootstrap_extend(struct dm_space_map *sm, dm_block_t extra_blocks) |
| 557 | { |
Joe Thornber | 88a488f | 2013-05-10 14:37:17 +0100 | [diff] [blame] | 558 | DMERR("bootstrap doesn't support extend"); |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 559 | |
| 560 | return -EINVAL; |
| 561 | } |
| 562 | |
| 563 | static int sm_bootstrap_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count) |
| 564 | { |
| 565 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 566 | |
| 567 | return smm->ll.nr_blocks; |
| 568 | } |
| 569 | |
| 570 | static int sm_bootstrap_get_nr_free(struct dm_space_map *sm, dm_block_t *count) |
| 571 | { |
| 572 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 573 | |
| 574 | *count = smm->ll.nr_blocks - smm->begin; |
| 575 | |
| 576 | return 0; |
| 577 | } |
| 578 | |
| 579 | static int sm_bootstrap_get_count(struct dm_space_map *sm, dm_block_t b, |
| 580 | uint32_t *result) |
| 581 | { |
| 582 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 583 | |
| 584 | return b < smm->begin ? 1 : 0; |
| 585 | } |
| 586 | |
| 587 | static int sm_bootstrap_count_is_more_than_one(struct dm_space_map *sm, |
| 588 | dm_block_t b, int *result) |
| 589 | { |
| 590 | *result = 0; |
| 591 | |
| 592 | return 0; |
| 593 | } |
| 594 | |
| 595 | static int sm_bootstrap_set_count(struct dm_space_map *sm, dm_block_t b, |
| 596 | uint32_t count) |
| 597 | { |
Joe Thornber | 88a488f | 2013-05-10 14:37:17 +0100 | [diff] [blame] | 598 | DMERR("bootstrap doesn't support set_count"); |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 599 | |
| 600 | return -EINVAL; |
| 601 | } |
| 602 | |
| 603 | static int sm_bootstrap_new_block(struct dm_space_map *sm, dm_block_t *b) |
| 604 | { |
| 605 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 606 | |
| 607 | /* |
| 608 | * We know the entire device is unused. |
| 609 | */ |
| 610 | if (smm->begin == smm->ll.nr_blocks) |
| 611 | return -ENOSPC; |
| 612 | |
| 613 | *b = smm->begin++; |
| 614 | |
| 615 | return 0; |
| 616 | } |
| 617 | |
| 618 | static int sm_bootstrap_inc_block(struct dm_space_map *sm, dm_block_t b) |
| 619 | { |
| 620 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 621 | |
| 622 | return add_bop(smm, BOP_INC, b); |
| 623 | } |
| 624 | |
| 625 | static int sm_bootstrap_dec_block(struct dm_space_map *sm, dm_block_t b) |
| 626 | { |
| 627 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 628 | |
| 629 | return add_bop(smm, BOP_DEC, b); |
| 630 | } |
| 631 | |
| 632 | static int sm_bootstrap_commit(struct dm_space_map *sm) |
| 633 | { |
| 634 | return 0; |
| 635 | } |
| 636 | |
| 637 | static int sm_bootstrap_root_size(struct dm_space_map *sm, size_t *result) |
| 638 | { |
Joe Thornber | 88a488f | 2013-05-10 14:37:17 +0100 | [diff] [blame] | 639 | DMERR("bootstrap doesn't support root_size"); |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 640 | |
| 641 | return -EINVAL; |
| 642 | } |
| 643 | |
| 644 | static int sm_bootstrap_copy_root(struct dm_space_map *sm, void *where, |
| 645 | size_t max) |
| 646 | { |
Joe Thornber | 88a488f | 2013-05-10 14:37:17 +0100 | [diff] [blame] | 647 | DMERR("bootstrap doesn't support copy_root"); |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 648 | |
| 649 | return -EINVAL; |
| 650 | } |
| 651 | |
| 652 | static struct dm_space_map bootstrap_ops = { |
| 653 | .destroy = sm_bootstrap_destroy, |
| 654 | .extend = sm_bootstrap_extend, |
| 655 | .get_nr_blocks = sm_bootstrap_get_nr_blocks, |
| 656 | .get_nr_free = sm_bootstrap_get_nr_free, |
| 657 | .get_count = sm_bootstrap_get_count, |
| 658 | .count_is_more_than_one = sm_bootstrap_count_is_more_than_one, |
| 659 | .set_count = sm_bootstrap_set_count, |
| 660 | .inc_block = sm_bootstrap_inc_block, |
| 661 | .dec_block = sm_bootstrap_dec_block, |
| 662 | .new_block = sm_bootstrap_new_block, |
| 663 | .commit = sm_bootstrap_commit, |
| 664 | .root_size = sm_bootstrap_root_size, |
Joe Thornber | 7c3d3f2 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 665 | .copy_root = sm_bootstrap_copy_root, |
| 666 | .register_threshold_callback = NULL |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 667 | }; |
| 668 | |
| 669 | /*----------------------------------------------------------------*/ |
| 670 | |
Joe Thornber | 1921c56 | 2013-05-10 14:37:19 +0100 | [diff] [blame] | 671 | static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks) |
| 672 | { |
| 673 | int r, i; |
| 674 | enum allocation_event ev; |
| 675 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 676 | dm_block_t old_len = smm->ll.nr_blocks; |
| 677 | |
| 678 | /* |
| 679 | * Flick into a mode where all blocks get allocated in the new area. |
| 680 | */ |
| 681 | smm->begin = old_len; |
Joe Thornber | 7e664b3 | 2014-01-07 15:49:02 +0000 | [diff] [blame] | 682 | memcpy(sm, &bootstrap_ops, sizeof(*sm)); |
Joe Thornber | 1921c56 | 2013-05-10 14:37:19 +0100 | [diff] [blame] | 683 | |
| 684 | /* |
| 685 | * Extend. |
| 686 | */ |
| 687 | r = sm_ll_extend(&smm->ll, extra_blocks); |
Joe Thornber | 7e664b3 | 2014-01-07 15:49:02 +0000 | [diff] [blame] | 688 | if (r) |
| 689 | goto out; |
Joe Thornber | 1921c56 | 2013-05-10 14:37:19 +0100 | [diff] [blame] | 690 | |
Joe Thornber | fca0284 | 2014-01-21 11:07:32 +0000 | [diff] [blame] | 691 | /* |
| 692 | * We repeatedly increment then commit until the commit doesn't |
| 693 | * allocate any new blocks. |
| 694 | */ |
| 695 | do { |
| 696 | for (i = old_len; !r && i < smm->begin; i++) { |
| 697 | r = sm_ll_inc(&smm->ll, i, &ev); |
| 698 | if (r) |
| 699 | goto out; |
| 700 | } |
| 701 | old_len = smm->begin; |
| 702 | |
| 703 | r = sm_ll_commit(&smm->ll); |
Joe Thornber | 7e664b3 | 2014-01-07 15:49:02 +0000 | [diff] [blame] | 704 | if (r) |
| 705 | goto out; |
Joe Thornber | 7e664b3 | 2014-01-07 15:49:02 +0000 | [diff] [blame] | 706 | |
Joe Thornber | fca0284 | 2014-01-21 11:07:32 +0000 | [diff] [blame] | 707 | } while (old_len != smm->begin); |
Joe Thornber | 7e664b3 | 2014-01-07 15:49:02 +0000 | [diff] [blame] | 708 | |
| 709 | out: |
Joe Thornber | 1921c56 | 2013-05-10 14:37:19 +0100 | [diff] [blame] | 710 | /* |
| 711 | * Switch back to normal behaviour. |
| 712 | */ |
Joe Thornber | 7e664b3 | 2014-01-07 15:49:02 +0000 | [diff] [blame] | 713 | memcpy(sm, &ops, sizeof(*sm)); |
Joe Thornber | 1921c56 | 2013-05-10 14:37:19 +0100 | [diff] [blame] | 714 | return r; |
| 715 | } |
| 716 | |
| 717 | /*----------------------------------------------------------------*/ |
| 718 | |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 719 | struct dm_space_map *dm_sm_metadata_init(void) |
| 720 | { |
| 721 | struct sm_metadata *smm; |
| 722 | |
| 723 | smm = kmalloc(sizeof(*smm), GFP_KERNEL); |
| 724 | if (!smm) |
| 725 | return ERR_PTR(-ENOMEM); |
| 726 | |
| 727 | memcpy(&smm->sm, &ops, sizeof(smm->sm)); |
| 728 | |
| 729 | return &smm->sm; |
| 730 | } |
| 731 | |
| 732 | int dm_sm_metadata_create(struct dm_space_map *sm, |
| 733 | struct dm_transaction_manager *tm, |
| 734 | dm_block_t nr_blocks, |
| 735 | dm_block_t superblock) |
| 736 | { |
| 737 | int r; |
| 738 | dm_block_t i; |
| 739 | enum allocation_event ev; |
| 740 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 741 | |
| 742 | smm->begin = superblock + 1; |
| 743 | smm->recursion_count = 0; |
| 744 | smm->allocated_this_transaction = 0; |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 745 | brb_init(&smm->uncommitted); |
Joe Thornber | 2fc4802 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 746 | threshold_init(&smm->threshold); |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 747 | |
| 748 | memcpy(&smm->sm, &bootstrap_ops, sizeof(smm->sm)); |
| 749 | |
| 750 | r = sm_ll_new_metadata(&smm->ll, tm); |
| 751 | if (r) |
| 752 | return r; |
| 753 | |
Mike Snitzer | 7d48935 | 2014-02-12 23:58:15 -0500 | [diff] [blame] | 754 | if (nr_blocks > DM_SM_METADATA_MAX_BLOCKS) |
| 755 | nr_blocks = DM_SM_METADATA_MAX_BLOCKS; |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 756 | r = sm_ll_extend(&smm->ll, nr_blocks); |
| 757 | if (r) |
| 758 | return r; |
| 759 | |
| 760 | memcpy(&smm->sm, &ops, sizeof(smm->sm)); |
| 761 | |
| 762 | /* |
| 763 | * Now we need to update the newly created data structures with the |
| 764 | * allocated blocks that they were built from. |
| 765 | */ |
| 766 | for (i = superblock; !r && i < smm->begin; i++) |
| 767 | r = sm_ll_inc(&smm->ll, i, &ev); |
| 768 | |
| 769 | if (r) |
| 770 | return r; |
| 771 | |
| 772 | return sm_metadata_commit(sm); |
| 773 | } |
| 774 | |
| 775 | int dm_sm_metadata_open(struct dm_space_map *sm, |
| 776 | struct dm_transaction_manager *tm, |
| 777 | void *root_le, size_t len) |
| 778 | { |
| 779 | int r; |
| 780 | struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm); |
| 781 | |
| 782 | r = sm_ll_open_metadata(&smm->ll, tm, root_le, len); |
| 783 | if (r) |
| 784 | return r; |
| 785 | |
| 786 | smm->begin = 0; |
| 787 | smm->recursion_count = 0; |
| 788 | smm->allocated_this_transaction = 0; |
Joe Thornber | cebc2de | 2014-03-07 14:57:19 +0000 | [diff] [blame] | 789 | brb_init(&smm->uncommitted); |
Joe Thornber | 2fc4802 | 2013-05-10 14:37:20 +0100 | [diff] [blame] | 790 | threshold_init(&smm->threshold); |
Joe Thornber | 3241b1d | 2011-10-31 20:19:11 +0000 | [diff] [blame] | 791 | |
| 792 | memcpy(&smm->old_ll, &smm->ll, sizeof(smm->old_ll)); |
| 793 | return 0; |
| 794 | } |