Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1 | /* |
| 2 | * Block Translation Table |
| 3 | * Copyright (c) 2014-2015, Intel Corporation. |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify it |
| 6 | * under the terms and conditions of the GNU General Public License, |
| 7 | * version 2, as published by the Free Software Foundation. |
| 8 | * |
| 9 | * This program is distributed in the hope it will be useful, but WITHOUT |
| 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 12 | * more details. |
| 13 | */ |
| 14 | #include <linux/highmem.h> |
| 15 | #include <linux/debugfs.h> |
| 16 | #include <linux/blkdev.h> |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/device.h> |
| 19 | #include <linux/mutex.h> |
| 20 | #include <linux/hdreg.h> |
| 21 | #include <linux/genhd.h> |
| 22 | #include <linux/sizes.h> |
| 23 | #include <linux/ndctl.h> |
| 24 | #include <linux/fs.h> |
| 25 | #include <linux/nd.h> |
| 26 | #include "btt.h" |
| 27 | #include "nd.h" |
| 28 | |
| 29 | enum log_ent_request { |
| 30 | LOG_NEW_ENT = 0, |
| 31 | LOG_OLD_ENT |
| 32 | }; |
| 33 | |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 34 | static int arena_read_bytes(struct arena_info *arena, resource_size_t offset, |
| 35 | void *buf, size_t n) |
| 36 | { |
| 37 | struct nd_btt *nd_btt = arena->nd_btt; |
| 38 | struct nd_namespace_common *ndns = nd_btt->ndns; |
| 39 | |
| 40 | /* arena offsets are 4K from the base of the device */ |
| 41 | offset += SZ_4K; |
| 42 | return nvdimm_read_bytes(ndns, offset, buf, n); |
| 43 | } |
| 44 | |
| 45 | static int arena_write_bytes(struct arena_info *arena, resource_size_t offset, |
| 46 | void *buf, size_t n) |
| 47 | { |
| 48 | struct nd_btt *nd_btt = arena->nd_btt; |
| 49 | struct nd_namespace_common *ndns = nd_btt->ndns; |
| 50 | |
| 51 | /* arena offsets are 4K from the base of the device */ |
| 52 | offset += SZ_4K; |
| 53 | return nvdimm_write_bytes(ndns, offset, buf, n); |
| 54 | } |
| 55 | |
| 56 | static int btt_info_write(struct arena_info *arena, struct btt_sb *super) |
| 57 | { |
| 58 | int ret; |
| 59 | |
| 60 | ret = arena_write_bytes(arena, arena->info2off, super, |
| 61 | sizeof(struct btt_sb)); |
| 62 | if (ret) |
| 63 | return ret; |
| 64 | |
| 65 | return arena_write_bytes(arena, arena->infooff, super, |
| 66 | sizeof(struct btt_sb)); |
| 67 | } |
| 68 | |
| 69 | static int btt_info_read(struct arena_info *arena, struct btt_sb *super) |
| 70 | { |
| 71 | WARN_ON(!super); |
| 72 | return arena_read_bytes(arena, arena->infooff, super, |
| 73 | sizeof(struct btt_sb)); |
| 74 | } |
| 75 | |
| 76 | /* |
| 77 | * 'raw' version of btt_map write |
| 78 | * Assumptions: |
| 79 | * mapping is in little-endian |
| 80 | * mapping contains 'E' and 'Z' flags as desired |
| 81 | */ |
| 82 | static int __btt_map_write(struct arena_info *arena, u32 lba, __le32 mapping) |
| 83 | { |
| 84 | u64 ns_off = arena->mapoff + (lba * MAP_ENT_SIZE); |
| 85 | |
| 86 | WARN_ON(lba >= arena->external_nlba); |
| 87 | return arena_write_bytes(arena, ns_off, &mapping, MAP_ENT_SIZE); |
| 88 | } |
| 89 | |
| 90 | static int btt_map_write(struct arena_info *arena, u32 lba, u32 mapping, |
| 91 | u32 z_flag, u32 e_flag) |
| 92 | { |
| 93 | u32 ze; |
| 94 | __le32 mapping_le; |
| 95 | |
| 96 | /* |
| 97 | * This 'mapping' is supposed to be just the LBA mapping, without |
| 98 | * any flags set, so strip the flag bits. |
| 99 | */ |
| 100 | mapping &= MAP_LBA_MASK; |
| 101 | |
| 102 | ze = (z_flag << 1) + e_flag; |
| 103 | switch (ze) { |
| 104 | case 0: |
| 105 | /* |
| 106 | * We want to set neither of the Z or E flags, and |
| 107 | * in the actual layout, this means setting the bit |
| 108 | * positions of both to '1' to indicate a 'normal' |
| 109 | * map entry |
| 110 | */ |
| 111 | mapping |= MAP_ENT_NORMAL; |
| 112 | break; |
| 113 | case 1: |
| 114 | mapping |= (1 << MAP_ERR_SHIFT); |
| 115 | break; |
| 116 | case 2: |
| 117 | mapping |= (1 << MAP_TRIM_SHIFT); |
| 118 | break; |
| 119 | default: |
| 120 | /* |
| 121 | * The case where Z and E are both sent in as '1' could be |
| 122 | * construed as a valid 'normal' case, but we decide not to, |
| 123 | * to avoid confusion |
| 124 | */ |
| 125 | WARN_ONCE(1, "Invalid use of Z and E flags\n"); |
| 126 | return -EIO; |
| 127 | } |
| 128 | |
| 129 | mapping_le = cpu_to_le32(mapping); |
| 130 | return __btt_map_write(arena, lba, mapping_le); |
| 131 | } |
| 132 | |
| 133 | static int btt_map_read(struct arena_info *arena, u32 lba, u32 *mapping, |
| 134 | int *trim, int *error) |
| 135 | { |
| 136 | int ret; |
| 137 | __le32 in; |
| 138 | u32 raw_mapping, postmap, ze, z_flag, e_flag; |
| 139 | u64 ns_off = arena->mapoff + (lba * MAP_ENT_SIZE); |
| 140 | |
| 141 | WARN_ON(lba >= arena->external_nlba); |
| 142 | |
| 143 | ret = arena_read_bytes(arena, ns_off, &in, MAP_ENT_SIZE); |
| 144 | if (ret) |
| 145 | return ret; |
| 146 | |
| 147 | raw_mapping = le32_to_cpu(in); |
| 148 | |
| 149 | z_flag = (raw_mapping & MAP_TRIM_MASK) >> MAP_TRIM_SHIFT; |
| 150 | e_flag = (raw_mapping & MAP_ERR_MASK) >> MAP_ERR_SHIFT; |
| 151 | ze = (z_flag << 1) + e_flag; |
| 152 | postmap = raw_mapping & MAP_LBA_MASK; |
| 153 | |
| 154 | /* Reuse the {z,e}_flag variables for *trim and *error */ |
| 155 | z_flag = 0; |
| 156 | e_flag = 0; |
| 157 | |
| 158 | switch (ze) { |
| 159 | case 0: |
| 160 | /* Initial state. Return postmap = premap */ |
| 161 | *mapping = lba; |
| 162 | break; |
| 163 | case 1: |
| 164 | *mapping = postmap; |
| 165 | e_flag = 1; |
| 166 | break; |
| 167 | case 2: |
| 168 | *mapping = postmap; |
| 169 | z_flag = 1; |
| 170 | break; |
| 171 | case 3: |
| 172 | *mapping = postmap; |
| 173 | break; |
| 174 | default: |
| 175 | return -EIO; |
| 176 | } |
| 177 | |
| 178 | if (trim) |
| 179 | *trim = z_flag; |
| 180 | if (error) |
| 181 | *error = e_flag; |
| 182 | |
| 183 | return ret; |
| 184 | } |
| 185 | |
| 186 | static int btt_log_read_pair(struct arena_info *arena, u32 lane, |
| 187 | struct log_entry *ent) |
| 188 | { |
| 189 | WARN_ON(!ent); |
| 190 | return arena_read_bytes(arena, |
| 191 | arena->logoff + (2 * lane * LOG_ENT_SIZE), ent, |
| 192 | 2 * LOG_ENT_SIZE); |
| 193 | } |
| 194 | |
| 195 | static struct dentry *debugfs_root; |
| 196 | |
| 197 | static void arena_debugfs_init(struct arena_info *a, struct dentry *parent, |
| 198 | int idx) |
| 199 | { |
| 200 | char dirname[32]; |
| 201 | struct dentry *d; |
| 202 | |
| 203 | /* If for some reason, parent bttN was not created, exit */ |
| 204 | if (!parent) |
| 205 | return; |
| 206 | |
| 207 | snprintf(dirname, 32, "arena%d", idx); |
| 208 | d = debugfs_create_dir(dirname, parent); |
| 209 | if (IS_ERR_OR_NULL(d)) |
| 210 | return; |
| 211 | a->debugfs_dir = d; |
| 212 | |
| 213 | debugfs_create_x64("size", S_IRUGO, d, &a->size); |
| 214 | debugfs_create_x64("external_lba_start", S_IRUGO, d, |
| 215 | &a->external_lba_start); |
| 216 | debugfs_create_x32("internal_nlba", S_IRUGO, d, &a->internal_nlba); |
| 217 | debugfs_create_u32("internal_lbasize", S_IRUGO, d, |
| 218 | &a->internal_lbasize); |
| 219 | debugfs_create_x32("external_nlba", S_IRUGO, d, &a->external_nlba); |
| 220 | debugfs_create_u32("external_lbasize", S_IRUGO, d, |
| 221 | &a->external_lbasize); |
| 222 | debugfs_create_u32("nfree", S_IRUGO, d, &a->nfree); |
| 223 | debugfs_create_u16("version_major", S_IRUGO, d, &a->version_major); |
| 224 | debugfs_create_u16("version_minor", S_IRUGO, d, &a->version_minor); |
| 225 | debugfs_create_x64("nextoff", S_IRUGO, d, &a->nextoff); |
| 226 | debugfs_create_x64("infooff", S_IRUGO, d, &a->infooff); |
| 227 | debugfs_create_x64("dataoff", S_IRUGO, d, &a->dataoff); |
| 228 | debugfs_create_x64("mapoff", S_IRUGO, d, &a->mapoff); |
| 229 | debugfs_create_x64("logoff", S_IRUGO, d, &a->logoff); |
| 230 | debugfs_create_x64("info2off", S_IRUGO, d, &a->info2off); |
| 231 | debugfs_create_x32("flags", S_IRUGO, d, &a->flags); |
| 232 | } |
| 233 | |
| 234 | static void btt_debugfs_init(struct btt *btt) |
| 235 | { |
| 236 | int i = 0; |
| 237 | struct arena_info *arena; |
| 238 | |
| 239 | btt->debugfs_dir = debugfs_create_dir(dev_name(&btt->nd_btt->dev), |
| 240 | debugfs_root); |
| 241 | if (IS_ERR_OR_NULL(btt->debugfs_dir)) |
| 242 | return; |
| 243 | |
| 244 | list_for_each_entry(arena, &btt->arena_list, list) { |
| 245 | arena_debugfs_init(arena, btt->debugfs_dir, i); |
| 246 | i++; |
| 247 | } |
| 248 | } |
| 249 | |
| 250 | /* |
| 251 | * This function accepts two log entries, and uses the |
| 252 | * sequence number to find the 'older' entry. |
| 253 | * It also updates the sequence number in this old entry to |
| 254 | * make it the 'new' one if the mark_flag is set. |
| 255 | * Finally, it returns which of the entries was the older one. |
| 256 | * |
| 257 | * TODO The logic feels a bit kludge-y. make it better.. |
| 258 | */ |
| 259 | static int btt_log_get_old(struct log_entry *ent) |
| 260 | { |
| 261 | int old; |
| 262 | |
| 263 | /* |
| 264 | * the first ever time this is seen, the entry goes into [0] |
| 265 | * the next time, the following logic works out to put this |
| 266 | * (next) entry into [1] |
| 267 | */ |
| 268 | if (ent[0].seq == 0) { |
| 269 | ent[0].seq = cpu_to_le32(1); |
| 270 | return 0; |
| 271 | } |
| 272 | |
| 273 | if (ent[0].seq == ent[1].seq) |
| 274 | return -EINVAL; |
| 275 | if (le32_to_cpu(ent[0].seq) + le32_to_cpu(ent[1].seq) > 5) |
| 276 | return -EINVAL; |
| 277 | |
| 278 | if (le32_to_cpu(ent[0].seq) < le32_to_cpu(ent[1].seq)) { |
| 279 | if (le32_to_cpu(ent[1].seq) - le32_to_cpu(ent[0].seq) == 1) |
| 280 | old = 0; |
| 281 | else |
| 282 | old = 1; |
| 283 | } else { |
| 284 | if (le32_to_cpu(ent[0].seq) - le32_to_cpu(ent[1].seq) == 1) |
| 285 | old = 1; |
| 286 | else |
| 287 | old = 0; |
| 288 | } |
| 289 | |
| 290 | return old; |
| 291 | } |
| 292 | |
| 293 | static struct device *to_dev(struct arena_info *arena) |
| 294 | { |
| 295 | return &arena->nd_btt->dev; |
| 296 | } |
| 297 | |
| 298 | /* |
| 299 | * This function copies the desired (old/new) log entry into ent if |
| 300 | * it is not NULL. It returns the sub-slot number (0 or 1) |
| 301 | * where the desired log entry was found. Negative return values |
| 302 | * indicate errors. |
| 303 | */ |
| 304 | static int btt_log_read(struct arena_info *arena, u32 lane, |
| 305 | struct log_entry *ent, int old_flag) |
| 306 | { |
| 307 | int ret; |
| 308 | int old_ent, ret_ent; |
| 309 | struct log_entry log[2]; |
| 310 | |
| 311 | ret = btt_log_read_pair(arena, lane, log); |
| 312 | if (ret) |
| 313 | return -EIO; |
| 314 | |
| 315 | old_ent = btt_log_get_old(log); |
| 316 | if (old_ent < 0 || old_ent > 1) { |
| 317 | dev_info(to_dev(arena), |
| 318 | "log corruption (%d): lane %d seq [%d, %d]\n", |
| 319 | old_ent, lane, log[0].seq, log[1].seq); |
| 320 | /* TODO set error state? */ |
| 321 | return -EIO; |
| 322 | } |
| 323 | |
| 324 | ret_ent = (old_flag ? old_ent : (1 - old_ent)); |
| 325 | |
| 326 | if (ent != NULL) |
| 327 | memcpy(ent, &log[ret_ent], LOG_ENT_SIZE); |
| 328 | |
| 329 | return ret_ent; |
| 330 | } |
| 331 | |
| 332 | /* |
| 333 | * This function commits a log entry to media |
| 334 | * It does _not_ prepare the freelist entry for the next write |
| 335 | * btt_flog_write is the wrapper for updating the freelist elements |
| 336 | */ |
| 337 | static int __btt_log_write(struct arena_info *arena, u32 lane, |
| 338 | u32 sub, struct log_entry *ent) |
| 339 | { |
| 340 | int ret; |
| 341 | /* |
| 342 | * Ignore the padding in log_entry for calculating log_half. |
| 343 | * The entry is 'committed' when we write the sequence number, |
| 344 | * and we want to ensure that that is the last thing written. |
| 345 | * We don't bother writing the padding as that would be extra |
| 346 | * media wear and write amplification |
| 347 | */ |
| 348 | unsigned int log_half = (LOG_ENT_SIZE - 2 * sizeof(u64)) / 2; |
| 349 | u64 ns_off = arena->logoff + (((2 * lane) + sub) * LOG_ENT_SIZE); |
| 350 | void *src = ent; |
| 351 | |
| 352 | /* split the 16B write into atomic, durable halves */ |
| 353 | ret = arena_write_bytes(arena, ns_off, src, log_half); |
| 354 | if (ret) |
| 355 | return ret; |
| 356 | |
| 357 | ns_off += log_half; |
| 358 | src += log_half; |
| 359 | return arena_write_bytes(arena, ns_off, src, log_half); |
| 360 | } |
| 361 | |
| 362 | static int btt_flog_write(struct arena_info *arena, u32 lane, u32 sub, |
| 363 | struct log_entry *ent) |
| 364 | { |
| 365 | int ret; |
| 366 | |
| 367 | ret = __btt_log_write(arena, lane, sub, ent); |
| 368 | if (ret) |
| 369 | return ret; |
| 370 | |
| 371 | /* prepare the next free entry */ |
| 372 | arena->freelist[lane].sub = 1 - arena->freelist[lane].sub; |
| 373 | if (++(arena->freelist[lane].seq) == 4) |
| 374 | arena->freelist[lane].seq = 1; |
| 375 | arena->freelist[lane].block = le32_to_cpu(ent->old_map); |
| 376 | |
| 377 | return ret; |
| 378 | } |
| 379 | |
| 380 | /* |
| 381 | * This function initializes the BTT map to the initial state, which is |
| 382 | * all-zeroes, and indicates an identity mapping |
| 383 | */ |
| 384 | static int btt_map_init(struct arena_info *arena) |
| 385 | { |
| 386 | int ret = -EINVAL; |
| 387 | void *zerobuf; |
| 388 | size_t offset = 0; |
| 389 | size_t chunk_size = SZ_2M; |
| 390 | size_t mapsize = arena->logoff - arena->mapoff; |
| 391 | |
| 392 | zerobuf = kzalloc(chunk_size, GFP_KERNEL); |
| 393 | if (!zerobuf) |
| 394 | return -ENOMEM; |
| 395 | |
| 396 | while (mapsize) { |
| 397 | size_t size = min(mapsize, chunk_size); |
| 398 | |
| 399 | ret = arena_write_bytes(arena, arena->mapoff + offset, zerobuf, |
| 400 | size); |
| 401 | if (ret) |
| 402 | goto free; |
| 403 | |
| 404 | offset += size; |
| 405 | mapsize -= size; |
| 406 | cond_resched(); |
| 407 | } |
| 408 | |
| 409 | free: |
| 410 | kfree(zerobuf); |
| 411 | return ret; |
| 412 | } |
| 413 | |
| 414 | /* |
| 415 | * This function initializes the BTT log with 'fake' entries pointing |
| 416 | * to the initial reserved set of blocks as being free |
| 417 | */ |
| 418 | static int btt_log_init(struct arena_info *arena) |
| 419 | { |
| 420 | int ret; |
| 421 | u32 i; |
| 422 | struct log_entry log, zerolog; |
| 423 | |
| 424 | memset(&zerolog, 0, sizeof(zerolog)); |
| 425 | |
| 426 | for (i = 0; i < arena->nfree; i++) { |
| 427 | log.lba = cpu_to_le32(i); |
| 428 | log.old_map = cpu_to_le32(arena->external_nlba + i); |
| 429 | log.new_map = cpu_to_le32(arena->external_nlba + i); |
| 430 | log.seq = cpu_to_le32(LOG_SEQ_INIT); |
| 431 | ret = __btt_log_write(arena, i, 0, &log); |
| 432 | if (ret) |
| 433 | return ret; |
| 434 | ret = __btt_log_write(arena, i, 1, &zerolog); |
| 435 | if (ret) |
| 436 | return ret; |
| 437 | } |
| 438 | |
| 439 | return 0; |
| 440 | } |
| 441 | |
| 442 | static int btt_freelist_init(struct arena_info *arena) |
| 443 | { |
| 444 | int old, new, ret; |
| 445 | u32 i, map_entry; |
| 446 | struct log_entry log_new, log_old; |
| 447 | |
| 448 | arena->freelist = kcalloc(arena->nfree, sizeof(struct free_entry), |
| 449 | GFP_KERNEL); |
| 450 | if (!arena->freelist) |
| 451 | return -ENOMEM; |
| 452 | |
| 453 | for (i = 0; i < arena->nfree; i++) { |
| 454 | old = btt_log_read(arena, i, &log_old, LOG_OLD_ENT); |
| 455 | if (old < 0) |
| 456 | return old; |
| 457 | |
| 458 | new = btt_log_read(arena, i, &log_new, LOG_NEW_ENT); |
| 459 | if (new < 0) |
| 460 | return new; |
| 461 | |
| 462 | /* sub points to the next one to be overwritten */ |
| 463 | arena->freelist[i].sub = 1 - new; |
| 464 | arena->freelist[i].seq = nd_inc_seq(le32_to_cpu(log_new.seq)); |
| 465 | arena->freelist[i].block = le32_to_cpu(log_new.old_map); |
| 466 | |
| 467 | /* This implies a newly created or untouched flog entry */ |
| 468 | if (log_new.old_map == log_new.new_map) |
| 469 | continue; |
| 470 | |
| 471 | /* Check if map recovery is needed */ |
| 472 | ret = btt_map_read(arena, le32_to_cpu(log_new.lba), &map_entry, |
| 473 | NULL, NULL); |
| 474 | if (ret) |
| 475 | return ret; |
| 476 | if ((le32_to_cpu(log_new.new_map) != map_entry) && |
| 477 | (le32_to_cpu(log_new.old_map) == map_entry)) { |
| 478 | /* |
| 479 | * Last transaction wrote the flog, but wasn't able |
| 480 | * to complete the map write. So fix up the map. |
| 481 | */ |
| 482 | ret = btt_map_write(arena, le32_to_cpu(log_new.lba), |
| 483 | le32_to_cpu(log_new.new_map), 0, 0); |
| 484 | if (ret) |
| 485 | return ret; |
| 486 | } |
| 487 | |
| 488 | } |
| 489 | |
| 490 | return 0; |
| 491 | } |
| 492 | |
| 493 | static int btt_rtt_init(struct arena_info *arena) |
| 494 | { |
| 495 | arena->rtt = kcalloc(arena->nfree, sizeof(u32), GFP_KERNEL); |
| 496 | if (arena->rtt == NULL) |
| 497 | return -ENOMEM; |
| 498 | |
| 499 | return 0; |
| 500 | } |
| 501 | |
| 502 | static int btt_maplocks_init(struct arena_info *arena) |
| 503 | { |
| 504 | u32 i; |
| 505 | |
| 506 | arena->map_locks = kcalloc(arena->nfree, sizeof(struct aligned_lock), |
| 507 | GFP_KERNEL); |
| 508 | if (!arena->map_locks) |
| 509 | return -ENOMEM; |
| 510 | |
| 511 | for (i = 0; i < arena->nfree; i++) |
| 512 | spin_lock_init(&arena->map_locks[i].lock); |
| 513 | |
| 514 | return 0; |
| 515 | } |
| 516 | |
| 517 | static struct arena_info *alloc_arena(struct btt *btt, size_t size, |
| 518 | size_t start, size_t arena_off) |
| 519 | { |
| 520 | struct arena_info *arena; |
| 521 | u64 logsize, mapsize, datasize; |
| 522 | u64 available = size; |
| 523 | |
| 524 | arena = kzalloc(sizeof(struct arena_info), GFP_KERNEL); |
| 525 | if (!arena) |
| 526 | return NULL; |
| 527 | arena->nd_btt = btt->nd_btt; |
| 528 | |
| 529 | if (!size) |
| 530 | return arena; |
| 531 | |
| 532 | arena->size = size; |
| 533 | arena->external_lba_start = start; |
| 534 | arena->external_lbasize = btt->lbasize; |
| 535 | arena->internal_lbasize = roundup(arena->external_lbasize, |
| 536 | INT_LBASIZE_ALIGNMENT); |
| 537 | arena->nfree = BTT_DEFAULT_NFREE; |
| 538 | arena->version_major = 1; |
| 539 | arena->version_minor = 1; |
| 540 | |
| 541 | if (available % BTT_PG_SIZE) |
| 542 | available -= (available % BTT_PG_SIZE); |
| 543 | |
| 544 | /* Two pages are reserved for the super block and its copy */ |
| 545 | available -= 2 * BTT_PG_SIZE; |
| 546 | |
| 547 | /* The log takes a fixed amount of space based on nfree */ |
| 548 | logsize = roundup(2 * arena->nfree * sizeof(struct log_entry), |
| 549 | BTT_PG_SIZE); |
| 550 | available -= logsize; |
| 551 | |
| 552 | /* Calculate optimal split between map and data area */ |
| 553 | arena->internal_nlba = div_u64(available - BTT_PG_SIZE, |
| 554 | arena->internal_lbasize + MAP_ENT_SIZE); |
| 555 | arena->external_nlba = arena->internal_nlba - arena->nfree; |
| 556 | |
| 557 | mapsize = roundup((arena->external_nlba * MAP_ENT_SIZE), BTT_PG_SIZE); |
| 558 | datasize = available - mapsize; |
| 559 | |
| 560 | /* 'Absolute' values, relative to start of storage space */ |
| 561 | arena->infooff = arena_off; |
| 562 | arena->dataoff = arena->infooff + BTT_PG_SIZE; |
| 563 | arena->mapoff = arena->dataoff + datasize; |
| 564 | arena->logoff = arena->mapoff + mapsize; |
| 565 | arena->info2off = arena->logoff + logsize; |
| 566 | return arena; |
| 567 | } |
| 568 | |
| 569 | static void free_arenas(struct btt *btt) |
| 570 | { |
| 571 | struct arena_info *arena, *next; |
| 572 | |
| 573 | list_for_each_entry_safe(arena, next, &btt->arena_list, list) { |
| 574 | list_del(&arena->list); |
| 575 | kfree(arena->rtt); |
| 576 | kfree(arena->map_locks); |
| 577 | kfree(arena->freelist); |
| 578 | debugfs_remove_recursive(arena->debugfs_dir); |
| 579 | kfree(arena); |
| 580 | } |
| 581 | } |
| 582 | |
| 583 | /* |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 584 | * This function reads an existing valid btt superblock and |
| 585 | * populates the corresponding arena_info struct |
| 586 | */ |
| 587 | static void parse_arena_meta(struct arena_info *arena, struct btt_sb *super, |
| 588 | u64 arena_off) |
| 589 | { |
| 590 | arena->internal_nlba = le32_to_cpu(super->internal_nlba); |
| 591 | arena->internal_lbasize = le32_to_cpu(super->internal_lbasize); |
| 592 | arena->external_nlba = le32_to_cpu(super->external_nlba); |
| 593 | arena->external_lbasize = le32_to_cpu(super->external_lbasize); |
| 594 | arena->nfree = le32_to_cpu(super->nfree); |
| 595 | arena->version_major = le16_to_cpu(super->version_major); |
| 596 | arena->version_minor = le16_to_cpu(super->version_minor); |
| 597 | |
| 598 | arena->nextoff = (super->nextoff == 0) ? 0 : (arena_off + |
| 599 | le64_to_cpu(super->nextoff)); |
| 600 | arena->infooff = arena_off; |
| 601 | arena->dataoff = arena_off + le64_to_cpu(super->dataoff); |
| 602 | arena->mapoff = arena_off + le64_to_cpu(super->mapoff); |
| 603 | arena->logoff = arena_off + le64_to_cpu(super->logoff); |
| 604 | arena->info2off = arena_off + le64_to_cpu(super->info2off); |
| 605 | |
Dan Williams | 5e32940 | 2015-07-11 10:02:46 -0400 | [diff] [blame] | 606 | arena->size = (le64_to_cpu(super->nextoff) > 0) |
| 607 | ? (le64_to_cpu(super->nextoff)) |
| 608 | : (arena->info2off - arena->infooff + BTT_PG_SIZE); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 609 | |
| 610 | arena->flags = le32_to_cpu(super->flags); |
| 611 | } |
| 612 | |
| 613 | static int discover_arenas(struct btt *btt) |
| 614 | { |
| 615 | int ret = 0; |
| 616 | struct arena_info *arena; |
| 617 | struct btt_sb *super; |
| 618 | size_t remaining = btt->rawsize; |
| 619 | u64 cur_nlba = 0; |
| 620 | size_t cur_off = 0; |
| 621 | int num_arenas = 0; |
| 622 | |
| 623 | super = kzalloc(sizeof(*super), GFP_KERNEL); |
| 624 | if (!super) |
| 625 | return -ENOMEM; |
| 626 | |
| 627 | while (remaining) { |
| 628 | /* Alloc memory for arena */ |
| 629 | arena = alloc_arena(btt, 0, 0, 0); |
| 630 | if (!arena) { |
| 631 | ret = -ENOMEM; |
| 632 | goto out_super; |
| 633 | } |
| 634 | |
| 635 | arena->infooff = cur_off; |
| 636 | ret = btt_info_read(arena, super); |
| 637 | if (ret) |
| 638 | goto out; |
| 639 | |
Vishal Verma | ab45e76 | 2015-07-29 14:58:08 -0600 | [diff] [blame] | 640 | if (!nd_btt_arena_is_valid(btt->nd_btt, super)) { |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 641 | if (remaining == btt->rawsize) { |
| 642 | btt->init_state = INIT_NOTFOUND; |
| 643 | dev_info(to_dev(arena), "No existing arenas\n"); |
| 644 | goto out; |
| 645 | } else { |
| 646 | dev_info(to_dev(arena), |
| 647 | "Found corrupted metadata!\n"); |
| 648 | ret = -ENODEV; |
| 649 | goto out; |
| 650 | } |
| 651 | } |
| 652 | |
| 653 | arena->external_lba_start = cur_nlba; |
| 654 | parse_arena_meta(arena, super, cur_off); |
| 655 | |
| 656 | ret = btt_freelist_init(arena); |
| 657 | if (ret) |
| 658 | goto out; |
| 659 | |
| 660 | ret = btt_rtt_init(arena); |
| 661 | if (ret) |
| 662 | goto out; |
| 663 | |
| 664 | ret = btt_maplocks_init(arena); |
| 665 | if (ret) |
| 666 | goto out; |
| 667 | |
| 668 | list_add_tail(&arena->list, &btt->arena_list); |
| 669 | |
| 670 | remaining -= arena->size; |
| 671 | cur_off += arena->size; |
| 672 | cur_nlba += arena->external_nlba; |
| 673 | num_arenas++; |
| 674 | |
| 675 | if (arena->nextoff == 0) |
| 676 | break; |
| 677 | } |
| 678 | btt->num_arenas = num_arenas; |
| 679 | btt->nlba = cur_nlba; |
| 680 | btt->init_state = INIT_READY; |
| 681 | |
| 682 | kfree(super); |
| 683 | return ret; |
| 684 | |
| 685 | out: |
| 686 | kfree(arena); |
| 687 | free_arenas(btt); |
| 688 | out_super: |
| 689 | kfree(super); |
| 690 | return ret; |
| 691 | } |
| 692 | |
| 693 | static int create_arenas(struct btt *btt) |
| 694 | { |
| 695 | size_t remaining = btt->rawsize; |
| 696 | size_t cur_off = 0; |
| 697 | |
| 698 | while (remaining) { |
| 699 | struct arena_info *arena; |
| 700 | size_t arena_size = min_t(u64, ARENA_MAX_SIZE, remaining); |
| 701 | |
| 702 | remaining -= arena_size; |
| 703 | if (arena_size < ARENA_MIN_SIZE) |
| 704 | break; |
| 705 | |
| 706 | arena = alloc_arena(btt, arena_size, btt->nlba, cur_off); |
| 707 | if (!arena) { |
| 708 | free_arenas(btt); |
| 709 | return -ENOMEM; |
| 710 | } |
| 711 | btt->nlba += arena->external_nlba; |
| 712 | if (remaining >= ARENA_MIN_SIZE) |
| 713 | arena->nextoff = arena->size; |
| 714 | else |
| 715 | arena->nextoff = 0; |
| 716 | cur_off += arena_size; |
| 717 | list_add_tail(&arena->list, &btt->arena_list); |
| 718 | } |
| 719 | |
| 720 | return 0; |
| 721 | } |
| 722 | |
| 723 | /* |
| 724 | * This function completes arena initialization by writing |
| 725 | * all the metadata. |
| 726 | * It is only called for an uninitialized arena when a write |
| 727 | * to that arena occurs for the first time. |
| 728 | */ |
Vishal Verma | fbde141 | 2015-07-29 14:58:07 -0600 | [diff] [blame] | 729 | static int btt_arena_write_layout(struct arena_info *arena) |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 730 | { |
| 731 | int ret; |
Dan Williams | e145574 | 2015-07-30 17:57:47 -0400 | [diff] [blame] | 732 | u64 sum; |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 733 | struct btt_sb *super; |
Vishal Verma | fbde141 | 2015-07-29 14:58:07 -0600 | [diff] [blame] | 734 | struct nd_btt *nd_btt = arena->nd_btt; |
Vishal Verma | 6ec6895 | 2015-07-29 14:58:09 -0600 | [diff] [blame] | 735 | const u8 *parent_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 736 | |
| 737 | ret = btt_map_init(arena); |
| 738 | if (ret) |
| 739 | return ret; |
| 740 | |
| 741 | ret = btt_log_init(arena); |
| 742 | if (ret) |
| 743 | return ret; |
| 744 | |
| 745 | super = kzalloc(sizeof(struct btt_sb), GFP_NOIO); |
| 746 | if (!super) |
| 747 | return -ENOMEM; |
| 748 | |
| 749 | strncpy(super->signature, BTT_SIG, BTT_SIG_LEN); |
Vishal Verma | fbde141 | 2015-07-29 14:58:07 -0600 | [diff] [blame] | 750 | memcpy(super->uuid, nd_btt->uuid, 16); |
Vishal Verma | 6ec6895 | 2015-07-29 14:58:09 -0600 | [diff] [blame] | 751 | memcpy(super->parent_uuid, parent_uuid, 16); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 752 | super->flags = cpu_to_le32(arena->flags); |
| 753 | super->version_major = cpu_to_le16(arena->version_major); |
| 754 | super->version_minor = cpu_to_le16(arena->version_minor); |
| 755 | super->external_lbasize = cpu_to_le32(arena->external_lbasize); |
| 756 | super->external_nlba = cpu_to_le32(arena->external_nlba); |
| 757 | super->internal_lbasize = cpu_to_le32(arena->internal_lbasize); |
| 758 | super->internal_nlba = cpu_to_le32(arena->internal_nlba); |
| 759 | super->nfree = cpu_to_le32(arena->nfree); |
| 760 | super->infosize = cpu_to_le32(sizeof(struct btt_sb)); |
| 761 | super->nextoff = cpu_to_le64(arena->nextoff); |
| 762 | /* |
| 763 | * Subtract arena->infooff (arena start) so numbers are relative |
| 764 | * to 'this' arena |
| 765 | */ |
| 766 | super->dataoff = cpu_to_le64(arena->dataoff - arena->infooff); |
| 767 | super->mapoff = cpu_to_le64(arena->mapoff - arena->infooff); |
| 768 | super->logoff = cpu_to_le64(arena->logoff - arena->infooff); |
| 769 | super->info2off = cpu_to_le64(arena->info2off - arena->infooff); |
| 770 | |
| 771 | super->flags = 0; |
Dan Williams | e145574 | 2015-07-30 17:57:47 -0400 | [diff] [blame] | 772 | sum = nd_sb_checksum((struct nd_gen_sb *) super); |
| 773 | super->checksum = cpu_to_le64(sum); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 774 | |
| 775 | ret = btt_info_write(arena, super); |
| 776 | |
| 777 | kfree(super); |
| 778 | return ret; |
| 779 | } |
| 780 | |
| 781 | /* |
| 782 | * This function completes the initialization for the BTT namespace |
| 783 | * such that it is ready to accept IOs |
| 784 | */ |
| 785 | static int btt_meta_init(struct btt *btt) |
| 786 | { |
| 787 | int ret = 0; |
| 788 | struct arena_info *arena; |
| 789 | |
| 790 | mutex_lock(&btt->init_lock); |
| 791 | list_for_each_entry(arena, &btt->arena_list, list) { |
Vishal Verma | fbde141 | 2015-07-29 14:58:07 -0600 | [diff] [blame] | 792 | ret = btt_arena_write_layout(arena); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 793 | if (ret) |
| 794 | goto unlock; |
| 795 | |
| 796 | ret = btt_freelist_init(arena); |
| 797 | if (ret) |
| 798 | goto unlock; |
| 799 | |
| 800 | ret = btt_rtt_init(arena); |
| 801 | if (ret) |
| 802 | goto unlock; |
| 803 | |
| 804 | ret = btt_maplocks_init(arena); |
| 805 | if (ret) |
| 806 | goto unlock; |
| 807 | } |
| 808 | |
| 809 | btt->init_state = INIT_READY; |
| 810 | |
| 811 | unlock: |
| 812 | mutex_unlock(&btt->init_lock); |
| 813 | return ret; |
| 814 | } |
| 815 | |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 816 | static u32 btt_meta_size(struct btt *btt) |
| 817 | { |
| 818 | return btt->lbasize - btt->sector_size; |
| 819 | } |
| 820 | |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 821 | /* |
| 822 | * This function calculates the arena in which the given LBA lies |
| 823 | * by doing a linear walk. This is acceptable since we expect only |
| 824 | * a few arenas. If we have backing devices that get much larger, |
| 825 | * we can construct a balanced binary tree of arenas at init time |
| 826 | * so that this range search becomes faster. |
| 827 | */ |
| 828 | static int lba_to_arena(struct btt *btt, sector_t sector, __u32 *premap, |
| 829 | struct arena_info **arena) |
| 830 | { |
| 831 | struct arena_info *arena_list; |
| 832 | __u64 lba = div_u64(sector << SECTOR_SHIFT, btt->sector_size); |
| 833 | |
| 834 | list_for_each_entry(arena_list, &btt->arena_list, list) { |
| 835 | if (lba < arena_list->external_nlba) { |
| 836 | *arena = arena_list; |
| 837 | *premap = lba; |
| 838 | return 0; |
| 839 | } |
| 840 | lba -= arena_list->external_nlba; |
| 841 | } |
| 842 | |
| 843 | return -EIO; |
| 844 | } |
| 845 | |
| 846 | /* |
| 847 | * The following (lock_map, unlock_map) are mostly just to improve |
| 848 | * readability, since they index into an array of locks |
| 849 | */ |
| 850 | static void lock_map(struct arena_info *arena, u32 premap) |
| 851 | __acquires(&arena->map_locks[idx].lock) |
| 852 | { |
| 853 | u32 idx = (premap * MAP_ENT_SIZE / L1_CACHE_BYTES) % arena->nfree; |
| 854 | |
| 855 | spin_lock(&arena->map_locks[idx].lock); |
| 856 | } |
| 857 | |
| 858 | static void unlock_map(struct arena_info *arena, u32 premap) |
| 859 | __releases(&arena->map_locks[idx].lock) |
| 860 | { |
| 861 | u32 idx = (premap * MAP_ENT_SIZE / L1_CACHE_BYTES) % arena->nfree; |
| 862 | |
| 863 | spin_unlock(&arena->map_locks[idx].lock); |
| 864 | } |
| 865 | |
| 866 | static u64 to_namespace_offset(struct arena_info *arena, u64 lba) |
| 867 | { |
| 868 | return arena->dataoff + ((u64)lba * arena->internal_lbasize); |
| 869 | } |
| 870 | |
| 871 | static int btt_data_read(struct arena_info *arena, struct page *page, |
| 872 | unsigned int off, u32 lba, u32 len) |
| 873 | { |
| 874 | int ret; |
| 875 | u64 nsoff = to_namespace_offset(arena, lba); |
| 876 | void *mem = kmap_atomic(page); |
| 877 | |
| 878 | ret = arena_read_bytes(arena, nsoff, mem + off, len); |
| 879 | kunmap_atomic(mem); |
| 880 | |
| 881 | return ret; |
| 882 | } |
| 883 | |
| 884 | static int btt_data_write(struct arena_info *arena, u32 lba, |
| 885 | struct page *page, unsigned int off, u32 len) |
| 886 | { |
| 887 | int ret; |
| 888 | u64 nsoff = to_namespace_offset(arena, lba); |
| 889 | void *mem = kmap_atomic(page); |
| 890 | |
| 891 | ret = arena_write_bytes(arena, nsoff, mem + off, len); |
| 892 | kunmap_atomic(mem); |
| 893 | |
| 894 | return ret; |
| 895 | } |
| 896 | |
| 897 | static void zero_fill_data(struct page *page, unsigned int off, u32 len) |
| 898 | { |
| 899 | void *mem = kmap_atomic(page); |
| 900 | |
| 901 | memset(mem + off, 0, len); |
| 902 | kunmap_atomic(mem); |
| 903 | } |
| 904 | |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 905 | #ifdef CONFIG_BLK_DEV_INTEGRITY |
| 906 | static int btt_rw_integrity(struct btt *btt, struct bio_integrity_payload *bip, |
| 907 | struct arena_info *arena, u32 postmap, int rw) |
| 908 | { |
| 909 | unsigned int len = btt_meta_size(btt); |
| 910 | u64 meta_nsoff; |
| 911 | int ret = 0; |
| 912 | |
| 913 | if (bip == NULL) |
| 914 | return 0; |
| 915 | |
| 916 | meta_nsoff = to_namespace_offset(arena, postmap) + btt->sector_size; |
| 917 | |
| 918 | while (len) { |
| 919 | unsigned int cur_len; |
| 920 | struct bio_vec bv; |
| 921 | void *mem; |
| 922 | |
| 923 | bv = bvec_iter_bvec(bip->bip_vec, bip->bip_iter); |
| 924 | /* |
| 925 | * The 'bv' obtained from bvec_iter_bvec has its .bv_len and |
| 926 | * .bv_offset already adjusted for iter->bi_bvec_done, and we |
| 927 | * can use those directly |
| 928 | */ |
| 929 | |
| 930 | cur_len = min(len, bv.bv_len); |
| 931 | mem = kmap_atomic(bv.bv_page); |
| 932 | if (rw) |
| 933 | ret = arena_write_bytes(arena, meta_nsoff, |
| 934 | mem + bv.bv_offset, cur_len); |
| 935 | else |
| 936 | ret = arena_read_bytes(arena, meta_nsoff, |
| 937 | mem + bv.bv_offset, cur_len); |
| 938 | |
| 939 | kunmap_atomic(mem); |
| 940 | if (ret) |
| 941 | return ret; |
| 942 | |
| 943 | len -= cur_len; |
| 944 | meta_nsoff += cur_len; |
| 945 | bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len); |
| 946 | } |
| 947 | |
| 948 | return ret; |
| 949 | } |
| 950 | |
| 951 | #else /* CONFIG_BLK_DEV_INTEGRITY */ |
| 952 | static int btt_rw_integrity(struct btt *btt, struct bio_integrity_payload *bip, |
| 953 | struct arena_info *arena, u32 postmap, int rw) |
| 954 | { |
| 955 | return 0; |
| 956 | } |
| 957 | #endif |
| 958 | |
| 959 | static int btt_read_pg(struct btt *btt, struct bio_integrity_payload *bip, |
| 960 | struct page *page, unsigned int off, sector_t sector, |
| 961 | unsigned int len) |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 962 | { |
| 963 | int ret = 0; |
| 964 | int t_flag, e_flag; |
| 965 | struct arena_info *arena = NULL; |
| 966 | u32 lane = 0, premap, postmap; |
| 967 | |
| 968 | while (len) { |
| 969 | u32 cur_len; |
| 970 | |
| 971 | lane = nd_region_acquire_lane(btt->nd_region); |
| 972 | |
| 973 | ret = lba_to_arena(btt, sector, &premap, &arena); |
| 974 | if (ret) |
| 975 | goto out_lane; |
| 976 | |
| 977 | cur_len = min(btt->sector_size, len); |
| 978 | |
| 979 | ret = btt_map_read(arena, premap, &postmap, &t_flag, &e_flag); |
| 980 | if (ret) |
| 981 | goto out_lane; |
| 982 | |
| 983 | /* |
| 984 | * We loop to make sure that the post map LBA didn't change |
| 985 | * from under us between writing the RTT and doing the actual |
| 986 | * read. |
| 987 | */ |
| 988 | while (1) { |
| 989 | u32 new_map; |
| 990 | |
| 991 | if (t_flag) { |
| 992 | zero_fill_data(page, off, cur_len); |
| 993 | goto out_lane; |
| 994 | } |
| 995 | |
| 996 | if (e_flag) { |
| 997 | ret = -EIO; |
| 998 | goto out_lane; |
| 999 | } |
| 1000 | |
| 1001 | arena->rtt[lane] = RTT_VALID | postmap; |
| 1002 | /* |
| 1003 | * Barrier to make sure this write is not reordered |
| 1004 | * to do the verification map_read before the RTT store |
| 1005 | */ |
| 1006 | barrier(); |
| 1007 | |
| 1008 | ret = btt_map_read(arena, premap, &new_map, &t_flag, |
| 1009 | &e_flag); |
| 1010 | if (ret) |
| 1011 | goto out_rtt; |
| 1012 | |
| 1013 | if (postmap == new_map) |
| 1014 | break; |
| 1015 | |
| 1016 | postmap = new_map; |
| 1017 | } |
| 1018 | |
| 1019 | ret = btt_data_read(arena, page, off, postmap, cur_len); |
| 1020 | if (ret) |
| 1021 | goto out_rtt; |
| 1022 | |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1023 | if (bip) { |
| 1024 | ret = btt_rw_integrity(btt, bip, arena, postmap, READ); |
| 1025 | if (ret) |
| 1026 | goto out_rtt; |
| 1027 | } |
| 1028 | |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1029 | arena->rtt[lane] = RTT_INVALID; |
| 1030 | nd_region_release_lane(btt->nd_region, lane); |
| 1031 | |
| 1032 | len -= cur_len; |
| 1033 | off += cur_len; |
| 1034 | sector += btt->sector_size >> SECTOR_SHIFT; |
| 1035 | } |
| 1036 | |
| 1037 | return 0; |
| 1038 | |
| 1039 | out_rtt: |
| 1040 | arena->rtt[lane] = RTT_INVALID; |
| 1041 | out_lane: |
| 1042 | nd_region_release_lane(btt->nd_region, lane); |
| 1043 | return ret; |
| 1044 | } |
| 1045 | |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1046 | static int btt_write_pg(struct btt *btt, struct bio_integrity_payload *bip, |
| 1047 | sector_t sector, struct page *page, unsigned int off, |
| 1048 | unsigned int len) |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1049 | { |
| 1050 | int ret = 0; |
| 1051 | struct arena_info *arena = NULL; |
| 1052 | u32 premap = 0, old_postmap, new_postmap, lane = 0, i; |
| 1053 | struct log_entry log; |
| 1054 | int sub; |
| 1055 | |
| 1056 | while (len) { |
| 1057 | u32 cur_len; |
| 1058 | |
| 1059 | lane = nd_region_acquire_lane(btt->nd_region); |
| 1060 | |
| 1061 | ret = lba_to_arena(btt, sector, &premap, &arena); |
| 1062 | if (ret) |
| 1063 | goto out_lane; |
| 1064 | cur_len = min(btt->sector_size, len); |
| 1065 | |
| 1066 | if ((arena->flags & IB_FLAG_ERROR_MASK) != 0) { |
| 1067 | ret = -EIO; |
| 1068 | goto out_lane; |
| 1069 | } |
| 1070 | |
| 1071 | new_postmap = arena->freelist[lane].block; |
| 1072 | |
| 1073 | /* Wait if the new block is being read from */ |
| 1074 | for (i = 0; i < arena->nfree; i++) |
| 1075 | while (arena->rtt[i] == (RTT_VALID | new_postmap)) |
| 1076 | cpu_relax(); |
| 1077 | |
| 1078 | |
| 1079 | if (new_postmap >= arena->internal_nlba) { |
| 1080 | ret = -EIO; |
| 1081 | goto out_lane; |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1082 | } |
| 1083 | |
| 1084 | ret = btt_data_write(arena, new_postmap, page, off, cur_len); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1085 | if (ret) |
| 1086 | goto out_lane; |
| 1087 | |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1088 | if (bip) { |
| 1089 | ret = btt_rw_integrity(btt, bip, arena, new_postmap, |
| 1090 | WRITE); |
| 1091 | if (ret) |
| 1092 | goto out_lane; |
| 1093 | } |
| 1094 | |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1095 | lock_map(arena, premap); |
| 1096 | ret = btt_map_read(arena, premap, &old_postmap, NULL, NULL); |
| 1097 | if (ret) |
| 1098 | goto out_map; |
| 1099 | if (old_postmap >= arena->internal_nlba) { |
| 1100 | ret = -EIO; |
| 1101 | goto out_map; |
| 1102 | } |
| 1103 | |
| 1104 | log.lba = cpu_to_le32(premap); |
| 1105 | log.old_map = cpu_to_le32(old_postmap); |
| 1106 | log.new_map = cpu_to_le32(new_postmap); |
| 1107 | log.seq = cpu_to_le32(arena->freelist[lane].seq); |
| 1108 | sub = arena->freelist[lane].sub; |
| 1109 | ret = btt_flog_write(arena, lane, sub, &log); |
| 1110 | if (ret) |
| 1111 | goto out_map; |
| 1112 | |
| 1113 | ret = btt_map_write(arena, premap, new_postmap, 0, 0); |
| 1114 | if (ret) |
| 1115 | goto out_map; |
| 1116 | |
| 1117 | unlock_map(arena, premap); |
| 1118 | nd_region_release_lane(btt->nd_region, lane); |
| 1119 | |
| 1120 | len -= cur_len; |
| 1121 | off += cur_len; |
| 1122 | sector += btt->sector_size >> SECTOR_SHIFT; |
| 1123 | } |
| 1124 | |
| 1125 | return 0; |
| 1126 | |
| 1127 | out_map: |
| 1128 | unlock_map(arena, premap); |
| 1129 | out_lane: |
| 1130 | nd_region_release_lane(btt->nd_region, lane); |
| 1131 | return ret; |
| 1132 | } |
| 1133 | |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1134 | static int btt_do_bvec(struct btt *btt, struct bio_integrity_payload *bip, |
| 1135 | struct page *page, unsigned int len, unsigned int off, |
| 1136 | int rw, sector_t sector) |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1137 | { |
| 1138 | int ret; |
| 1139 | |
| 1140 | if (rw == READ) { |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1141 | ret = btt_read_pg(btt, bip, page, off, sector, len); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1142 | flush_dcache_page(page); |
| 1143 | } else { |
| 1144 | flush_dcache_page(page); |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1145 | ret = btt_write_pg(btt, bip, sector, page, off, len); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1146 | } |
| 1147 | |
| 1148 | return ret; |
| 1149 | } |
| 1150 | |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 1151 | static blk_qc_t btt_make_request(struct request_queue *q, struct bio *bio) |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1152 | { |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1153 | struct bio_integrity_payload *bip = bio_integrity(bio); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1154 | struct btt *btt = q->queuedata; |
| 1155 | struct bvec_iter iter; |
Dan Williams | f0dc089 | 2015-05-16 12:28:53 -0400 | [diff] [blame] | 1156 | unsigned long start; |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1157 | struct bio_vec bvec; |
| 1158 | int err = 0, rw; |
Dan Williams | f0dc089 | 2015-05-16 12:28:53 -0400 | [diff] [blame] | 1159 | bool do_acct; |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1160 | |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1161 | /* |
| 1162 | * bio_integrity_enabled also checks if the bio already has an |
| 1163 | * integrity payload attached. If it does, we *don't* do a |
| 1164 | * bio_integrity_prep here - the payload has been generated by |
| 1165 | * another kernel subsystem, and we just pass it through. |
| 1166 | */ |
| 1167 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1168 | bio->bi_error = -EIO; |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1169 | goto out; |
| 1170 | } |
| 1171 | |
Dan Williams | f0dc089 | 2015-05-16 12:28:53 -0400 | [diff] [blame] | 1172 | do_acct = nd_iostat_start(bio, &start); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1173 | rw = bio_data_dir(bio); |
| 1174 | bio_for_each_segment(bvec, bio, iter) { |
| 1175 | unsigned int len = bvec.bv_len; |
| 1176 | |
| 1177 | BUG_ON(len > PAGE_SIZE); |
| 1178 | /* Make sure len is in multiples of sector size. */ |
| 1179 | /* XXX is this right? */ |
| 1180 | BUG_ON(len < btt->sector_size); |
| 1181 | BUG_ON(len % btt->sector_size); |
| 1182 | |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1183 | err = btt_do_bvec(btt, bip, bvec.bv_page, len, bvec.bv_offset, |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1184 | rw, iter.bi_sector); |
| 1185 | if (err) { |
| 1186 | dev_info(&btt->nd_btt->dev, |
| 1187 | "io error in %s sector %lld, len %d,\n", |
| 1188 | (rw == READ) ? "READ" : "WRITE", |
| 1189 | (unsigned long long) iter.bi_sector, len); |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1190 | bio->bi_error = err; |
Dan Williams | f0dc089 | 2015-05-16 12:28:53 -0400 | [diff] [blame] | 1191 | break; |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1192 | } |
| 1193 | } |
Dan Williams | f0dc089 | 2015-05-16 12:28:53 -0400 | [diff] [blame] | 1194 | if (do_acct) |
| 1195 | nd_iostat_end(bio, start); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1196 | |
| 1197 | out: |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1198 | bio_endio(bio); |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 1199 | return BLK_QC_T_NONE; |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1200 | } |
| 1201 | |
| 1202 | static int btt_rw_page(struct block_device *bdev, sector_t sector, |
| 1203 | struct page *page, int rw) |
| 1204 | { |
| 1205 | struct btt *btt = bdev->bd_disk->private_data; |
| 1206 | |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1207 | btt_do_bvec(btt, NULL, page, PAGE_CACHE_SIZE, 0, rw, sector); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1208 | page_endio(page, rw & WRITE, 0); |
| 1209 | return 0; |
| 1210 | } |
| 1211 | |
| 1212 | |
| 1213 | static int btt_getgeo(struct block_device *bd, struct hd_geometry *geo) |
| 1214 | { |
| 1215 | /* some standard values */ |
| 1216 | geo->heads = 1 << 6; |
| 1217 | geo->sectors = 1 << 5; |
| 1218 | geo->cylinders = get_capacity(bd->bd_disk) >> 11; |
| 1219 | return 0; |
| 1220 | } |
| 1221 | |
| 1222 | static const struct block_device_operations btt_fops = { |
| 1223 | .owner = THIS_MODULE, |
| 1224 | .rw_page = btt_rw_page, |
| 1225 | .getgeo = btt_getgeo, |
Dan Williams | 5813882 | 2015-06-23 20:08:34 -0400 | [diff] [blame] | 1226 | .revalidate_disk = nvdimm_revalidate_disk, |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1227 | }; |
| 1228 | |
| 1229 | static int btt_blk_init(struct btt *btt) |
| 1230 | { |
| 1231 | struct nd_btt *nd_btt = btt->nd_btt; |
| 1232 | struct nd_namespace_common *ndns = nd_btt->ndns; |
| 1233 | |
| 1234 | /* create a new disk and request queue for btt */ |
| 1235 | btt->btt_queue = blk_alloc_queue(GFP_KERNEL); |
| 1236 | if (!btt->btt_queue) |
| 1237 | return -ENOMEM; |
| 1238 | |
| 1239 | btt->btt_disk = alloc_disk(0); |
| 1240 | if (!btt->btt_disk) { |
| 1241 | blk_cleanup_queue(btt->btt_queue); |
| 1242 | return -ENOMEM; |
| 1243 | } |
| 1244 | |
| 1245 | nvdimm_namespace_disk_name(ndns, btt->btt_disk->disk_name); |
| 1246 | btt->btt_disk->driverfs_dev = &btt->nd_btt->dev; |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1247 | btt->btt_disk->first_minor = 0; |
| 1248 | btt->btt_disk->fops = &btt_fops; |
| 1249 | btt->btt_disk->private_data = btt; |
| 1250 | btt->btt_disk->queue = btt->btt_queue; |
| 1251 | btt->btt_disk->flags = GENHD_FL_EXT_DEVT; |
| 1252 | |
| 1253 | blk_queue_make_request(btt->btt_queue, btt_make_request); |
| 1254 | blk_queue_logical_block_size(btt->btt_queue, btt->sector_size); |
| 1255 | blk_queue_max_hw_sectors(btt->btt_queue, UINT_MAX); |
| 1256 | blk_queue_bounce_limit(btt->btt_queue, BLK_BOUNCE_ANY); |
| 1257 | queue_flag_set_unlocked(QUEUE_FLAG_NONROT, btt->btt_queue); |
| 1258 | btt->btt_queue->queuedata = btt; |
| 1259 | |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1260 | set_capacity(btt->btt_disk, 0); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1261 | add_disk(btt->btt_disk); |
Vishal Verma | 41cd8b7 | 2015-06-25 04:21:52 -0400 | [diff] [blame] | 1262 | if (btt_meta_size(btt)) { |
| 1263 | int rc = nd_integrity_init(btt->btt_disk, btt_meta_size(btt)); |
| 1264 | |
| 1265 | if (rc) { |
| 1266 | del_gendisk(btt->btt_disk); |
| 1267 | put_disk(btt->btt_disk); |
| 1268 | blk_cleanup_queue(btt->btt_queue); |
| 1269 | return rc; |
| 1270 | } |
| 1271 | } |
| 1272 | set_capacity(btt->btt_disk, btt->nlba * btt->sector_size >> 9); |
Dan Williams | 5813882 | 2015-06-23 20:08:34 -0400 | [diff] [blame] | 1273 | revalidate_disk(btt->btt_disk); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1274 | |
| 1275 | return 0; |
| 1276 | } |
| 1277 | |
| 1278 | static void btt_blk_cleanup(struct btt *btt) |
| 1279 | { |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1280 | del_gendisk(btt->btt_disk); |
| 1281 | put_disk(btt->btt_disk); |
| 1282 | blk_cleanup_queue(btt->btt_queue); |
| 1283 | } |
| 1284 | |
| 1285 | /** |
| 1286 | * btt_init - initialize a block translation table for the given device |
| 1287 | * @nd_btt: device with BTT geometry and backing device info |
| 1288 | * @rawsize: raw size in bytes of the backing device |
| 1289 | * @lbasize: lba size of the backing device |
| 1290 | * @uuid: A uuid for the backing device - this is stored on media |
| 1291 | * @maxlane: maximum number of parallel requests the device can handle |
| 1292 | * |
| 1293 | * Initialize a Block Translation Table on a backing device to provide |
| 1294 | * single sector power fail atomicity. |
| 1295 | * |
| 1296 | * Context: |
| 1297 | * Might sleep. |
| 1298 | * |
| 1299 | * Returns: |
| 1300 | * Pointer to a new struct btt on success, NULL on failure. |
| 1301 | */ |
| 1302 | static struct btt *btt_init(struct nd_btt *nd_btt, unsigned long long rawsize, |
| 1303 | u32 lbasize, u8 *uuid, struct nd_region *nd_region) |
| 1304 | { |
| 1305 | int ret; |
| 1306 | struct btt *btt; |
| 1307 | struct device *dev = &nd_btt->dev; |
| 1308 | |
| 1309 | btt = kzalloc(sizeof(struct btt), GFP_KERNEL); |
| 1310 | if (!btt) |
| 1311 | return NULL; |
| 1312 | |
| 1313 | btt->nd_btt = nd_btt; |
| 1314 | btt->rawsize = rawsize; |
| 1315 | btt->lbasize = lbasize; |
| 1316 | btt->sector_size = ((lbasize >= 4096) ? 4096 : 512); |
| 1317 | INIT_LIST_HEAD(&btt->arena_list); |
| 1318 | mutex_init(&btt->init_lock); |
| 1319 | btt->nd_region = nd_region; |
| 1320 | |
| 1321 | ret = discover_arenas(btt); |
| 1322 | if (ret) { |
| 1323 | dev_err(dev, "init: error in arena_discover: %d\n", ret); |
| 1324 | goto out_free; |
| 1325 | } |
| 1326 | |
Dan Williams | 5813882 | 2015-06-23 20:08:34 -0400 | [diff] [blame] | 1327 | if (btt->init_state != INIT_READY && nd_region->ro) { |
| 1328 | dev_info(dev, "%s is read-only, unable to init btt metadata\n", |
| 1329 | dev_name(&nd_region->dev)); |
| 1330 | goto out_free; |
| 1331 | } else if (btt->init_state != INIT_READY) { |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1332 | btt->num_arenas = (rawsize / ARENA_MAX_SIZE) + |
| 1333 | ((rawsize % ARENA_MAX_SIZE) ? 1 : 0); |
| 1334 | dev_dbg(dev, "init: %d arenas for %llu rawsize\n", |
| 1335 | btt->num_arenas, rawsize); |
| 1336 | |
| 1337 | ret = create_arenas(btt); |
| 1338 | if (ret) { |
| 1339 | dev_info(dev, "init: create_arenas: %d\n", ret); |
| 1340 | goto out_free; |
| 1341 | } |
| 1342 | |
| 1343 | ret = btt_meta_init(btt); |
| 1344 | if (ret) { |
| 1345 | dev_err(dev, "init: error in meta_init: %d\n", ret); |
Dan Williams | 5813882 | 2015-06-23 20:08:34 -0400 | [diff] [blame] | 1346 | goto out_free; |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1347 | } |
| 1348 | } |
| 1349 | |
| 1350 | ret = btt_blk_init(btt); |
| 1351 | if (ret) { |
| 1352 | dev_err(dev, "init: error in blk_init: %d\n", ret); |
| 1353 | goto out_free; |
| 1354 | } |
| 1355 | |
| 1356 | btt_debugfs_init(btt); |
| 1357 | |
| 1358 | return btt; |
| 1359 | |
| 1360 | out_free: |
| 1361 | kfree(btt); |
| 1362 | return NULL; |
| 1363 | } |
| 1364 | |
| 1365 | /** |
| 1366 | * btt_fini - de-initialize a BTT |
| 1367 | * @btt: the BTT handle that was generated by btt_init |
| 1368 | * |
| 1369 | * De-initialize a Block Translation Table on device removal |
| 1370 | * |
| 1371 | * Context: |
| 1372 | * Might sleep. |
| 1373 | */ |
| 1374 | static void btt_fini(struct btt *btt) |
| 1375 | { |
| 1376 | if (btt) { |
| 1377 | btt_blk_cleanup(btt); |
| 1378 | free_arenas(btt); |
| 1379 | debugfs_remove_recursive(btt->debugfs_dir); |
| 1380 | kfree(btt); |
| 1381 | } |
| 1382 | } |
| 1383 | |
| 1384 | int nvdimm_namespace_attach_btt(struct nd_namespace_common *ndns) |
| 1385 | { |
| 1386 | struct nd_btt *nd_btt = to_nd_btt(ndns->claim); |
| 1387 | struct nd_region *nd_region; |
| 1388 | struct btt *btt; |
| 1389 | size_t rawsize; |
| 1390 | |
| 1391 | if (!nd_btt->uuid || !nd_btt->ndns || !nd_btt->lbasize) |
| 1392 | return -ENODEV; |
| 1393 | |
| 1394 | rawsize = nvdimm_namespace_capacity(ndns) - SZ_4K; |
| 1395 | if (rawsize < ARENA_MIN_SIZE) { |
| 1396 | return -ENXIO; |
| 1397 | } |
| 1398 | nd_region = to_nd_region(nd_btt->dev.parent); |
| 1399 | btt = btt_init(nd_btt, rawsize, nd_btt->lbasize, nd_btt->uuid, |
| 1400 | nd_region); |
| 1401 | if (!btt) |
| 1402 | return -ENOMEM; |
| 1403 | nd_btt->btt = btt; |
| 1404 | |
| 1405 | return 0; |
| 1406 | } |
| 1407 | EXPORT_SYMBOL(nvdimm_namespace_attach_btt); |
| 1408 | |
| 1409 | int nvdimm_namespace_detach_btt(struct nd_namespace_common *ndns) |
| 1410 | { |
| 1411 | struct nd_btt *nd_btt = to_nd_btt(ndns->claim); |
| 1412 | struct btt *btt = nd_btt->btt; |
| 1413 | |
| 1414 | btt_fini(btt); |
| 1415 | nd_btt->btt = NULL; |
| 1416 | |
| 1417 | return 0; |
| 1418 | } |
| 1419 | EXPORT_SYMBOL(nvdimm_namespace_detach_btt); |
| 1420 | |
| 1421 | static int __init nd_btt_init(void) |
| 1422 | { |
NeilBrown | ff8e92d | 2016-03-10 08:59:28 +1100 | [diff] [blame] | 1423 | int rc = 0; |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1424 | |
| 1425 | debugfs_root = debugfs_create_dir("btt", NULL); |
NeilBrown | ff8e92d | 2016-03-10 08:59:28 +1100 | [diff] [blame] | 1426 | if (IS_ERR_OR_NULL(debugfs_root)) |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1427 | rc = -ENXIO; |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1428 | |
| 1429 | return rc; |
| 1430 | } |
| 1431 | |
| 1432 | static void __exit nd_btt_exit(void) |
| 1433 | { |
| 1434 | debugfs_remove_recursive(debugfs_root); |
Vishal Verma | 5212e11 | 2015-06-25 04:20:32 -0400 | [diff] [blame] | 1435 | } |
| 1436 | |
| 1437 | MODULE_ALIAS_ND_DEVICE(ND_DEVICE_BTT); |
| 1438 | MODULE_AUTHOR("Vishal Verma <vishal.l.verma@linux.intel.com>"); |
| 1439 | MODULE_LICENSE("GPL v2"); |
| 1440 | module_init(nd_btt_init); |
| 1441 | module_exit(nd_btt_exit); |