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