drivers/lightnvm/gennvm.c

   1 /*
   2  * Copyright (C) 2015 Matias Bjorling <m@bjorling.me>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License version
   6  * 2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
  16  * USA.
  17  *
  18  * Implementation of a generic nvm manager for Open-Channel SSDs.
  19  */
  20
  21 #include "gennvm.h"
  22
  23 static void gennvm_blocks_free(struct nvm_dev *dev)
  24 {
  25         struct gen_nvm *gn = dev->mp;
  26         struct gen_lun *lun;
  27         int i;
  28
  29         gennvm_for_each_lun(gn, lun, i) {
  30                 if (!lun->vlun.blocks)
  31                         break;
  32                 vfree(lun->vlun.blocks);
  33         }
  34 }
  35
  36 static void gennvm_luns_free(struct nvm_dev *dev)
  37 {
  38         struct gen_nvm *gn = dev->mp;
  39
  40         kfree(gn->luns);
  41 }
  42
  43 static int gennvm_luns_init(struct nvm_dev *dev, struct gen_nvm *gn)
  44 {
  45         struct gen_lun *lun;
  46         int i;
  47
  48         gn->luns = kcalloc(dev->nr_luns, sizeof(struct gen_lun), GFP_KERNEL);
  49         if (!gn->luns)
  50                 return -ENOMEM;
  51
  52         gennvm_for_each_lun(gn, lun, i) {
  53                 spin_lock_init(&lun->vlun.lock);
  54                 INIT_LIST_HEAD(&lun->free_list);
  55                 INIT_LIST_HEAD(&lun->used_list);
  56                 INIT_LIST_HEAD(&lun->bb_list);
  57
  58                 lun->reserved_blocks = 2; /* for GC only */
  59                 lun->vlun.id = i;
  60                 lun->vlun.lun_id = i % dev->luns_per_chnl;
  61                 lun->vlun.chnl_id = i / dev->luns_per_chnl;
  62                 lun->vlun.nr_free_blocks = dev->blks_per_lun;
  63                 lun->vlun.nr_inuse_blocks = 0;
  64                 lun->vlun.nr_bad_blocks = 0;
  65         }
  66         return 0;
  67 }
  68
  69 static int gennvm_block_bb(struct ppa_addr ppa, int nr_blocks, u8 *blks,
  70                                                                 void *private)
  71 {
  72         struct gen_nvm *gn = private;
  73         struct nvm_dev *dev = gn->dev;
  74         struct gen_lun *lun;
  75         struct nvm_block *blk;
  76         int i;
  77
  78         ppa = dev_to_generic_addr(gn->dev, ppa);
  79         lun = &gn->luns[(dev->nr_luns * ppa.g.ch) + ppa.g.lun];
  80
  81         for (i = 0; i < nr_blocks; i++) {
  82                 if (blks[i] == 0)
  83                         continue;
  84
  85                 blk = &lun->vlun.blocks[i];
  86                 if (!blk) {
  87                         pr_err("gennvm: BB data is out of bounds.\n");
  88                         return -EINVAL;
  89                 }
  90
  91                 list_move_tail(&blk->list, &lun->bb_list);
  92                 lun->vlun.nr_bad_blocks++;
  93         }
  94
  95         return 0;
  96 }
  97
  98 static int gennvm_block_map(u64 slba, u32 nlb, __le64 *entries, void *private)
  99 {
 100         struct nvm_dev *dev = private;
 101         struct gen_nvm *gn = dev->mp;
 102         sector_t max_pages = dev->total_pages * (dev->sec_size >> 9);
 103         u64 elba = slba + nlb;
 104         struct gen_lun *lun;
 105         struct nvm_block *blk;
 106         u64 i;
 107         int lun_id;
 108
 109         if (unlikely(elba > dev->total_pages)) {
 110                 pr_err("gennvm: L2P data from device is out of bounds!\n");
 111                 return -EINVAL;
 112         }
 113
 114         for (i = 0; i < nlb; i++) {
 115                 u64 pba = le64_to_cpu(entries[i]);
 116
 117                 if (unlikely(pba >= max_pages && pba != U64_MAX)) {
 118                         pr_err("gennvm: L2P data entry is out of bounds!\n");
 119                         return -EINVAL;
 120                 }
 121
 122                 /* Address zero is a special one. The first page on a disk is
 123                  * protected. It often holds internal device boot
 124                  * information.
 125                  */
 126                 if (!pba)
 127                         continue;
 128
 129                 /* resolve block from physical address */
 130                 lun_id = div_u64(pba, dev->sec_per_lun);
 131                 lun = &gn->luns[lun_id];
 132
 133                 /* Calculate block offset into lun */
 134                 pba = pba - (dev->sec_per_lun * lun_id);
 135                 blk = &lun->vlun.blocks[div_u64(pba, dev->sec_per_blk)];
 136
 137                 if (!blk->type) {
 138                         /* at this point, we don't know anything about the
 139                          * block. It's up to the FTL on top to re-etablish the
 140                          * block state
 141                          */
 142                         list_move_tail(&blk->list, &lun->used_list);
 143                         blk->type = 1;
 144                         lun->vlun.nr_free_blocks--;
 145                         lun->vlun.nr_inuse_blocks++;
 146                 }
 147         }
 148
 149         return 0;
 150 }
 151
 152 static int gennvm_blocks_init(struct nvm_dev *dev, struct gen_nvm *gn)
 153 {
 154         struct gen_lun *lun;
 155         struct nvm_block *block;
 156         sector_t lun_iter, blk_iter, cur_block_id = 0;
 157         int ret;
 158
 159         gennvm_for_each_lun(gn, lun, lun_iter) {
 160                 lun->vlun.blocks = vzalloc(sizeof(struct nvm_block) *
 161                                                         dev->blks_per_lun);
 162                 if (!lun->vlun.blocks)
 163                         return -ENOMEM;
 164
 165                 for (blk_iter = 0; blk_iter < dev->blks_per_lun; blk_iter++) {
 166                         block = &lun->vlun.blocks[blk_iter];
 167
 168                         INIT_LIST_HEAD(&block->list);
 169
 170                         block->lun = &lun->vlun;
 171                         block->id = cur_block_id++;
 172
 173                         /* First block is reserved for device */
 174                         if (unlikely(lun_iter == 0 && blk_iter == 0)) {
 175                                 lun->vlun.nr_free_blocks--;
 176                                 continue;
 177                         }
 178
 179                         list_add_tail(&block->list, &lun->free_list);
 180                 }
 181
 182                 if (dev->ops->get_bb_tbl) {
 183                         struct ppa_addr ppa;
 184
 185                         ppa.ppa = 0;
 186                         ppa.g.ch = lun->vlun.chnl_id;
 187                         ppa.g.lun = lun->vlun.id;
 188                         ppa = generic_to_dev_addr(dev, ppa);
 189
 190                         ret = dev->ops->get_bb_tbl(dev->q, ppa,
 191                                                 dev->blks_per_lun,
 192                                                 gennvm_block_bb, gn);
 193                         if (ret)
 194                                 pr_err("gennvm: could not read BB table\n");
 195                 }
 196         }
 197
 198         if (dev->ops->get_l2p_tbl) {
 199                 ret = dev->ops->get_l2p_tbl(dev->q, 0, dev->total_pages,
 200                                                         gennvm_block_map, dev);
 201                 if (ret) {
 202                         pr_err("gennvm: could not read L2P table.\n");
 203                         pr_warn("gennvm: default block initialization");
 204                 }
 205         }
 206
 207         return 0;
 208 }
 209
 210 static void gennvm_free(struct nvm_dev *dev)
 211 {
 212         gennvm_blocks_free(dev);
 213         gennvm_luns_free(dev);
 214         kfree(dev->mp);
 215         dev->mp = NULL;
 216 }
 217
 218 static int gennvm_register(struct nvm_dev *dev)
 219 {
 220         struct gen_nvm *gn;
 221         int ret;
 222
 223         gn = kzalloc(sizeof(struct gen_nvm), GFP_KERNEL);
 224         if (!gn)
 225                 return -ENOMEM;
 226
 227         gn->dev = dev;
 228         gn->nr_luns = dev->nr_luns;
 229         dev->mp = gn;
 230
 231         ret = gennvm_luns_init(dev, gn);
 232         if (ret) {
 233                 pr_err("gennvm: could not initialize luns\n");
 234                 goto err;
 235         }
 236
 237         ret = gennvm_blocks_init(dev, gn);
 238         if (ret) {
 239                 pr_err("gennvm: could not initialize blocks\n");
 240                 goto err;
 241         }
 242
 243         return 1;
 244 err:
 245         gennvm_free(dev);
 246         return ret;
 247 }
 248
 249 static void gennvm_unregister(struct nvm_dev *dev)
 250 {
 251         gennvm_free(dev);
 252 }
 253
 254 static struct nvm_block *gennvm_get_blk(struct nvm_dev *dev,
 255                                 struct nvm_lun *vlun, unsigned long flags)
 256 {
 257         struct gen_lun *lun = container_of(vlun, struct gen_lun, vlun);
 258         struct nvm_block *blk = NULL;
 259         int is_gc = flags & NVM_IOTYPE_GC;
 260
 261         spin_lock(&vlun->lock);
 262
 263         if (list_empty(&lun->free_list)) {
 264                 pr_err_ratelimited("gennvm: lun %u have no free pages available",
 265                                                                 lun->vlun.id);
 266                 spin_unlock(&vlun->lock);
 267                 goto out;
 268         }
 269
 270         while (!is_gc && lun->vlun.nr_free_blocks < lun->reserved_blocks) {
 271                 spin_unlock(&vlun->lock);
 272                 goto out;
 273         }
 274
 275         blk = list_first_entry(&lun->free_list, struct nvm_block, list);
 276         list_move_tail(&blk->list, &lun->used_list);
 277         blk->type = 1;
 278
 279         lun->vlun.nr_free_blocks--;
 280         lun->vlun.nr_inuse_blocks++;
 281
 282         spin_unlock(&vlun->lock);
 283 out:
 284         return blk;
 285 }
 286
 287 static void gennvm_put_blk(struct nvm_dev *dev, struct nvm_block *blk)
 288 {
 289         struct nvm_lun *vlun = blk->lun;
 290         struct gen_lun *lun = container_of(vlun, struct gen_lun, vlun);
 291
 292         spin_lock(&vlun->lock);
 293
 294         switch (blk->type) {
 295         case 1:
 296                 list_move_tail(&blk->list, &lun->free_list);
 297                 lun->vlun.nr_free_blocks++;
 298                 lun->vlun.nr_inuse_blocks--;
 299                 blk->type = 0;
 300                 break;
 301         case 2:
 302                 list_move_tail(&blk->list, &lun->bb_list);
 303                 lun->vlun.nr_bad_blocks++;
 304                 lun->vlun.nr_inuse_blocks--;
 305                 break;
 306         default:
 307                 WARN_ON_ONCE(1);
 308                 pr_err("gennvm: erroneous block type (%lu -> %u)\n",
 309                                                         blk->id, blk->type);
 310                 list_move_tail(&blk->list, &lun->bb_list);
 311                 lun->vlun.nr_bad_blocks++;
 312                 lun->vlun.nr_inuse_blocks--;
 313         }
 314
 315         spin_unlock(&vlun->lock);
 316 }
 317
 318 static void gennvm_addr_to_generic_mode(struct nvm_dev *dev, struct nvm_rq *rqd)
 319 {
 320         int i;
 321
 322         if (rqd->nr_pages > 1) {
 323                 for (i = 0; i < rqd->nr_pages; i++)
 324                         rqd->ppa_list[i] = dev_to_generic_addr(dev,
 325                                                         rqd->ppa_list[i]);
 326         } else {
 327                 rqd->ppa_addr = dev_to_generic_addr(dev, rqd->ppa_addr);
 328         }
 329 }
 330
 331 static void gennvm_generic_to_addr_mode(struct nvm_dev *dev, struct nvm_rq *rqd)
 332 {
 333         int i;
 334
 335         if (rqd->nr_pages > 1) {
 336                 for (i = 0; i < rqd->nr_pages; i++)
 337                         rqd->ppa_list[i] = generic_to_dev_addr(dev,
 338                                                         rqd->ppa_list[i]);
 339         } else {
 340                 rqd->ppa_addr = generic_to_dev_addr(dev, rqd->ppa_addr);
 341         }
 342 }
 343
 344 static int gennvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
 345 {
 346         if (!dev->ops->submit_io)
 347                 return 0;
 348
 349         /* Convert address space */
 350         gennvm_generic_to_addr_mode(dev, rqd);
 351
 352         rqd->dev = dev;
 353         return dev->ops->submit_io(dev->q, rqd);
 354 }
 355
 356 static void gennvm_blk_set_type(struct nvm_dev *dev, struct ppa_addr *ppa,
 357                                                                 int type)
 358 {
 359         struct gen_nvm *gn = dev->mp;
 360         struct gen_lun *lun;
 361         struct nvm_block *blk;
 362
 363         if (unlikely(ppa->g.ch > dev->nr_chnls ||
 364                                         ppa->g.lun > dev->luns_per_chnl ||
 365                                         ppa->g.blk > dev->blks_per_lun)) {
 366                 WARN_ON_ONCE(1);
 367                 pr_err("gennvm: ppa broken (ch: %u > %u lun: %u > %u blk: %u > %u",
 368                                 ppa->g.ch, dev->nr_chnls,
 369                                 ppa->g.lun, dev->luns_per_chnl,
 370                                 ppa->g.blk, dev->blks_per_lun);
 371                 return;
 372         }
 373
 374         lun = &gn->luns[ppa->g.lun * ppa->g.ch];
 375         blk = &lun->vlun.blocks[ppa->g.blk];
 376
 377         /* will be moved to bb list on put_blk from target */
 378         blk->type = type;
 379 }
 380
 381 /* mark block bad. It is expected the target recover from the error. */
 382 static void gennvm_mark_blk_bad(struct nvm_dev *dev, struct nvm_rq *rqd)
 383 {
 384         int i;
 385
 386         if (!dev->ops->set_bb_tbl)
 387                 return;
 388
 389         if (dev->ops->set_bb_tbl(dev->q, rqd, 1))
 390                 return;
 391
 392         gennvm_addr_to_generic_mode(dev, rqd);
 393
 394         /* look up blocks and mark them as bad */
 395         if (rqd->nr_pages > 1)
 396                 for (i = 0; i < rqd->nr_pages; i++)
 397                         gennvm_blk_set_type(dev, &rqd->ppa_list[i], 2);
 398         else
 399                 gennvm_blk_set_type(dev, &rqd->ppa_addr, 2);
 400 }
 401
 402 static int gennvm_end_io(struct nvm_rq *rqd, int error)
 403 {
 404         struct nvm_tgt_instance *ins = rqd->ins;
 405         int ret = 0;
 406
 407         switch (error) {
 408         case NVM_RSP_SUCCESS:
 409                 break;
 410         case NVM_RSP_ERR_EMPTYPAGE:
 411                 break;
 412         case NVM_RSP_ERR_FAILWRITE:
 413                 gennvm_mark_blk_bad(rqd->dev, rqd);
 414         default:
 415                 ret++;
 416         }
 417
 418         ret += ins->tt->end_io(rqd, error);
 419
 420         return ret;
 421 }
 422
 423 static int gennvm_erase_blk(struct nvm_dev *dev, struct nvm_block *blk,
 424                                                         unsigned long flags)
 425 {
 426         int plane_cnt = 0, pl_idx, ret;
 427         struct ppa_addr addr;
 428         struct nvm_rq rqd;
 429
 430         if (!dev->ops->erase_block)
 431                 return 0;
 432
 433         addr = block_to_ppa(dev, blk);
 434
 435         if (dev->plane_mode == NVM_PLANE_SINGLE) {
 436                 rqd.nr_pages = 1;
 437                 rqd.ppa_addr = addr;
 438         } else {
 439                 plane_cnt = (1 << dev->plane_mode);
 440                 rqd.nr_pages = plane_cnt;
 441
 442                 rqd.ppa_list = nvm_dev_dma_alloc(dev, GFP_KERNEL,
 443                                                         &rqd.dma_ppa_list);
 444                 if (!rqd.ppa_list) {
 445                         pr_err("gennvm: failed to allocate dma memory\n");
 446                         return -ENOMEM;
 447                 }
 448
 449                 for (pl_idx = 0; pl_idx < plane_cnt; pl_idx++) {
 450                         addr.g.pl = pl_idx;
 451                         rqd.ppa_list[pl_idx] = addr;
 452                 }
 453         }
 454
 455         gennvm_generic_to_addr_mode(dev, &rqd);
 456
 457         ret = dev->ops->erase_block(dev->q, &rqd);
 458
 459         if (plane_cnt)
 460                 nvm_dev_dma_free(dev, rqd.ppa_list, rqd.dma_ppa_list);
 461
 462         return ret;
 463 }
 464
 465 static struct nvm_lun *gennvm_get_lun(struct nvm_dev *dev, int lunid)
 466 {
 467         struct gen_nvm *gn = dev->mp;
 468
 469         return &gn->luns[lunid].vlun;
 470 }
 471
 472 static void gennvm_lun_info_print(struct nvm_dev *dev)
 473 {
 474         struct gen_nvm *gn = dev->mp;
 475         struct gen_lun *lun;
 476         unsigned int i;
 477
 478
 479         gennvm_for_each_lun(gn, lun, i) {
 480                 spin_lock(&lun->vlun.lock);
 481
 482                 pr_info("%s: lun%8u\t%u\t%u\t%u\n",
 483                                 dev->name, i,
 484                                 lun->vlun.nr_free_blocks,
 485                                 lun->vlun.nr_inuse_blocks,
 486                                 lun->vlun.nr_bad_blocks);
 487
 488                 spin_unlock(&lun->vlun.lock);
 489         }
 490 }
 491
 492 static struct nvmm_type gennvm = {
 493         .name           = "gennvm",
 494         .version        = {0, 1, 0},
 495
 496         .register_mgr   = gennvm_register,
 497         .unregister_mgr = gennvm_unregister,
 498
 499         .get_blk        = gennvm_get_blk,
 500         .put_blk        = gennvm_put_blk,
 501
 502         .submit_io      = gennvm_submit_io,
 503         .end_io         = gennvm_end_io,
 504         .erase_blk      = gennvm_erase_blk,
 505
 506         .get_lun        = gennvm_get_lun,
 507         .lun_info_print = gennvm_lun_info_print,
 508 };
 509
 510 static int __init gennvm_module_init(void)
 511 {
 512         return nvm_register_mgr(&gennvm);
 513 }
 514
 515 static void gennvm_module_exit(void)
 516 {
 517         nvm_unregister_mgr(&gennvm);
 518 }
 519
 520 module_init(gennvm_module_init);
 521 module_exit(gennvm_module_exit);
 522 MODULE_LICENSE("GPL v2");
 523 MODULE_DESCRIPTION("Generic media manager for Open-Channel SSDs");