drivers/lightnvm/core.c

   1 /*
   2  * Copyright (C) 2015 IT University of Copenhagen. All rights reserved.
   3  * Initial release: Matias Bjorling <m@bjorling.me>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License version
   7  * 2 as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; see the file COPYING.  If not, write to
  16  * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
  17  * USA.
  18  *
  19  */
  20
  21 #include <linux/blkdev.h>
  22 #include <linux/blk-mq.h>
  23 #include <linux/list.h>
  24 #include <linux/types.h>
  25 #include <linux/sem.h>
  26 #include <linux/bitmap.h>
  27 #include <linux/module.h>
  28 #include <linux/miscdevice.h>
  29 #include <linux/lightnvm.h>
  30 #include <linux/sched/sysctl.h>
  31 #include <uapi/linux/lightnvm.h>
  32
  33 static LIST_HEAD(nvm_targets);
  34 static LIST_HEAD(nvm_mgrs);
  35 static LIST_HEAD(nvm_devices);
  36 static DECLARE_RWSEM(nvm_lock);
  37
  38 static struct nvm_tgt_type *nvm_find_target_type(const char *name)
  39 {
  40         struct nvm_tgt_type *tt;
  41
  42         list_for_each_entry(tt, &nvm_targets, list)
  43                 if (!strcmp(name, tt->name))
  44                         return tt;
  45
  46         return NULL;
  47 }
  48
  49 int nvm_register_target(struct nvm_tgt_type *tt)
  50 {
  51         int ret = 0;
  52
  53         down_write(&nvm_lock);
  54         if (nvm_find_target_type(tt->name))
  55                 ret = -EEXIST;
  56         else
  57                 list_add(&tt->list, &nvm_targets);
  58         up_write(&nvm_lock);
  59
  60         return ret;
  61 }
  62 EXPORT_SYMBOL(nvm_register_target);
  63
  64 void nvm_unregister_target(struct nvm_tgt_type *tt)
  65 {
  66         if (!tt)
  67                 return;
  68
  69         down_write(&nvm_lock);
  70         list_del(&tt->list);
  71         up_write(&nvm_lock);
  72 }
  73 EXPORT_SYMBOL(nvm_unregister_target);
  74
  75 void *nvm_dev_dma_alloc(struct nvm_dev *dev, gfp_t mem_flags,
  76                                                         dma_addr_t *dma_handler)
  77 {
  78         return dev->ops->dev_dma_alloc(dev, dev->ppalist_pool, mem_flags,
  79                                                                 dma_handler);
  80 }
  81 EXPORT_SYMBOL(nvm_dev_dma_alloc);
  82
  83 void nvm_dev_dma_free(struct nvm_dev *dev, void *ppa_list,
  84                                                         dma_addr_t dma_handler)
  85 {
  86         dev->ops->dev_dma_free(dev->ppalist_pool, ppa_list, dma_handler);
  87 }
  88 EXPORT_SYMBOL(nvm_dev_dma_free);
  89
  90 static struct nvmm_type *nvm_find_mgr_type(const char *name)
  91 {
  92         struct nvmm_type *mt;
  93
  94         list_for_each_entry(mt, &nvm_mgrs, list)
  95                 if (!strcmp(name, mt->name))
  96                         return mt;
  97
  98         return NULL;
  99 }
 100
 101 struct nvmm_type *nvm_init_mgr(struct nvm_dev *dev)
 102 {
 103         struct nvmm_type *mt;
 104         int ret;
 105
 106         lockdep_assert_held(&nvm_lock);
 107
 108         list_for_each_entry(mt, &nvm_mgrs, list) {
 109                 if (strncmp(dev->sb.mmtype, mt->name, NVM_MMTYPE_LEN))
 110                         continue;
 111
 112                 ret = mt->register_mgr(dev);
 113                 if (ret < 0) {
 114                         pr_err("nvm: media mgr failed to init (%d) on dev %s\n",
 115                                                                 ret, dev->name);
 116                         return NULL; /* initialization failed */
 117                 } else if (ret > 0)
 118                         return mt;
 119         }
 120
 121         return NULL;
 122 }
 123
 124 int nvm_register_mgr(struct nvmm_type *mt)
 125 {
 126         struct nvm_dev *dev;
 127         int ret = 0;
 128
 129         down_write(&nvm_lock);
 130         if (nvm_find_mgr_type(mt->name)) {
 131                 ret = -EEXIST;
 132                 goto finish;
 133         } else {
 134                 list_add(&mt->list, &nvm_mgrs);
 135         }
 136
 137         /* try to register media mgr if any device have none configured */
 138         list_for_each_entry(dev, &nvm_devices, devices) {
 139                 if (dev->mt)
 140                         continue;
 141
 142                 dev->mt = nvm_init_mgr(dev);
 143         }
 144 finish:
 145         up_write(&nvm_lock);
 146
 147         return ret;
 148 }
 149 EXPORT_SYMBOL(nvm_register_mgr);
 150
 151 void nvm_unregister_mgr(struct nvmm_type *mt)
 152 {
 153         if (!mt)
 154                 return;
 155
 156         down_write(&nvm_lock);
 157         list_del(&mt->list);
 158         up_write(&nvm_lock);
 159 }
 160 EXPORT_SYMBOL(nvm_unregister_mgr);
 161
 162 static struct nvm_dev *nvm_find_nvm_dev(const char *name)
 163 {
 164         struct nvm_dev *dev;
 165
 166         list_for_each_entry(dev, &nvm_devices, devices)
 167                 if (!strcmp(name, dev->name))
 168                         return dev;
 169
 170         return NULL;
 171 }
 172
 173 struct nvm_block *nvm_get_blk_unlocked(struct nvm_dev *dev, struct nvm_lun *lun,
 174                                                         unsigned long flags)
 175 {
 176         return dev->mt->get_blk_unlocked(dev, lun, flags);
 177 }
 178 EXPORT_SYMBOL(nvm_get_blk_unlocked);
 179
 180 /* Assumes that all valid pages have already been moved on release to bm */
 181 void nvm_put_blk_unlocked(struct nvm_dev *dev, struct nvm_block *blk)
 182 {
 183         return dev->mt->put_blk_unlocked(dev, blk);
 184 }
 185 EXPORT_SYMBOL(nvm_put_blk_unlocked);
 186
 187 struct nvm_block *nvm_get_blk(struct nvm_dev *dev, struct nvm_lun *lun,
 188                                                         unsigned long flags)
 189 {
 190         return dev->mt->get_blk(dev, lun, flags);
 191 }
 192 EXPORT_SYMBOL(nvm_get_blk);
 193
 194 /* Assumes that all valid pages have already been moved on release to bm */
 195 void nvm_put_blk(struct nvm_dev *dev, struct nvm_block *blk)
 196 {
 197         return dev->mt->put_blk(dev, blk);
 198 }
 199 EXPORT_SYMBOL(nvm_put_blk);
 200
 201 int nvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
 202 {
 203         return dev->mt->submit_io(dev, rqd);
 204 }
 205 EXPORT_SYMBOL(nvm_submit_io);
 206
 207 int nvm_erase_blk(struct nvm_dev *dev, struct nvm_block *blk)
 208 {
 209         return dev->mt->erase_blk(dev, blk, 0);
 210 }
 211 EXPORT_SYMBOL(nvm_erase_blk);
 212
 213 void nvm_addr_to_generic_mode(struct nvm_dev *dev, struct nvm_rq *rqd)
 214 {
 215         int i;
 216
 217         if (rqd->nr_pages > 1) {
 218                 for (i = 0; i < rqd->nr_pages; i++)
 219                         rqd->ppa_list[i] = dev_to_generic_addr(dev,
 220                                                         rqd->ppa_list[i]);
 221         } else {
 222                 rqd->ppa_addr = dev_to_generic_addr(dev, rqd->ppa_addr);
 223         }
 224 }
 225 EXPORT_SYMBOL(nvm_addr_to_generic_mode);
 226
 227 void nvm_generic_to_addr_mode(struct nvm_dev *dev, struct nvm_rq *rqd)
 228 {
 229         int i;
 230
 231         if (rqd->nr_pages > 1) {
 232                 for (i = 0; i < rqd->nr_pages; i++)
 233                         rqd->ppa_list[i] = generic_to_dev_addr(dev,
 234                                                         rqd->ppa_list[i]);
 235         } else {
 236                 rqd->ppa_addr = generic_to_dev_addr(dev, rqd->ppa_addr);
 237         }
 238 }
 239 EXPORT_SYMBOL(nvm_generic_to_addr_mode);
 240
 241 int nvm_set_rqd_ppalist(struct nvm_dev *dev, struct nvm_rq *rqd,
 242                                         struct ppa_addr *ppas, int nr_ppas)
 243 {
 244         int i, plane_cnt, pl_idx;
 245
 246         if (dev->plane_mode == NVM_PLANE_SINGLE && nr_ppas == 1) {
 247                 rqd->nr_pages = 1;
 248                 rqd->ppa_addr = ppas[0];
 249
 250                 return 0;
 251         }
 252
 253         plane_cnt = dev->plane_mode;
 254         rqd->nr_pages = plane_cnt * nr_ppas;
 255
 256         if (dev->ops->max_phys_sect < rqd->nr_pages)
 257                 return -EINVAL;
 258
 259         rqd->ppa_list = nvm_dev_dma_alloc(dev, GFP_KERNEL, &rqd->dma_ppa_list);
 260         if (!rqd->ppa_list) {
 261                 pr_err("nvm: failed to allocate dma memory\n");
 262                 return -ENOMEM;
 263         }
 264
 265         for (pl_idx = 0; pl_idx < plane_cnt; pl_idx++) {
 266                 for (i = 0; i < nr_ppas; i++) {
 267                         ppas[i].g.pl = pl_idx;
 268                         rqd->ppa_list[(pl_idx * nr_ppas) + i] = ppas[i];
 269                 }
 270         }
 271
 272         return 0;
 273 }
 274 EXPORT_SYMBOL(nvm_set_rqd_ppalist);
 275
 276 void nvm_free_rqd_ppalist(struct nvm_dev *dev, struct nvm_rq *rqd)
 277 {
 278         if (!rqd->ppa_list)
 279                 return;
 280
 281         nvm_dev_dma_free(dev, rqd->ppa_list, rqd->dma_ppa_list);
 282 }
 283 EXPORT_SYMBOL(nvm_free_rqd_ppalist);
 284
 285 int nvm_erase_ppa(struct nvm_dev *dev, struct ppa_addr *ppas, int nr_ppas)
 286 {
 287         struct nvm_rq rqd;
 288         int ret;
 289
 290         if (!dev->ops->erase_block)
 291                 return 0;
 292
 293         memset(&rqd, 0, sizeof(struct nvm_rq));
 294
 295         ret = nvm_set_rqd_ppalist(dev, &rqd, ppas, nr_ppas);
 296         if (ret)
 297                 return ret;
 298
 299         nvm_generic_to_addr_mode(dev, &rqd);
 300
 301         ret = dev->ops->erase_block(dev, &rqd);
 302
 303         nvm_free_rqd_ppalist(dev, &rqd);
 304
 305         return ret;
 306 }
 307 EXPORT_SYMBOL(nvm_erase_ppa);
 308
 309 void nvm_end_io(struct nvm_rq *rqd, int error)
 310 {
 311         rqd->error = error;
 312         rqd->end_io(rqd);
 313 }
 314 EXPORT_SYMBOL(nvm_end_io);
 315
 316 static void nvm_end_io_sync(struct nvm_rq *rqd)
 317 {
 318         struct completion *waiting = rqd->wait;
 319
 320         rqd->wait = NULL;
 321
 322         complete(waiting);
 323 }
 324
 325 int __nvm_submit_ppa(struct nvm_dev *dev, struct nvm_rq *rqd, int opcode,
 326                                                 int flags, void *buf, int len)
 327 {
 328         DECLARE_COMPLETION_ONSTACK(wait);
 329         struct bio *bio;
 330         int ret;
 331         unsigned long hang_check;
 332
 333         bio = bio_map_kern(dev->q, buf, len, GFP_KERNEL);
 334         if (IS_ERR_OR_NULL(bio))
 335                 return -ENOMEM;
 336
 337         nvm_generic_to_addr_mode(dev, rqd);
 338
 339         rqd->dev = dev;
 340         rqd->opcode = opcode;
 341         rqd->flags = flags;
 342         rqd->bio = bio;
 343         rqd->wait = &wait;
 344         rqd->end_io = nvm_end_io_sync;
 345
 346         ret = dev->ops->submit_io(dev, rqd);
 347         if (ret) {
 348                 bio_put(bio);
 349                 return ret;
 350         }
 351
 352         /* Prevent hang_check timer from firing at us during very long I/O */
 353         hang_check = sysctl_hung_task_timeout_secs;
 354         if (hang_check)
 355                 while (!wait_for_completion_io_timeout(&wait, hang_check * (HZ/2)));
 356         else
 357                 wait_for_completion_io(&wait);
 358
 359         return rqd->error;
 360 }
 361
 362 /**
 363  * nvm_submit_ppa_list - submit user-defined ppa list to device. The user must
 364  *                       take to free ppa list if necessary.
 365  * @dev:        device
 366  * @ppa_list:   user created ppa_list
 367  * @nr_ppas:    length of ppa_list
 368  * @opcode:     device opcode
 369  * @flags:      device flags
 370  * @buf:        data buffer
 371  * @len:        data buffer length
 372  */
 373 int nvm_submit_ppa_list(struct nvm_dev *dev, struct ppa_addr *ppa_list,
 374                         int nr_ppas, int opcode, int flags, void *buf, int len)
 375 {
 376         struct nvm_rq rqd;
 377
 378         if (dev->ops->max_phys_sect < nr_ppas)
 379                 return -EINVAL;
 380
 381         memset(&rqd, 0, sizeof(struct nvm_rq));
 382
 383         rqd.nr_pages = nr_ppas;
 384         if (nr_ppas > 1)
 385                 rqd.ppa_list = ppa_list;
 386         else
 387                 rqd.ppa_addr = ppa_list[0];
 388
 389         return __nvm_submit_ppa(dev, &rqd, opcode, flags, buf, len);
 390 }
 391 EXPORT_SYMBOL(nvm_submit_ppa_list);
 392
 393 /**
 394  * nvm_submit_ppa - submit PPAs to device. PPAs will automatically be unfolded
 395  *                  as single, dual, quad plane PPAs depending on device type.
 396  * @dev:        device
 397  * @ppa:        user created ppa_list
 398  * @nr_ppas:    length of ppa_list
 399  * @opcode:     device opcode
 400  * @flags:      device flags
 401  * @buf:        data buffer
 402  * @len:        data buffer length
 403  */
 404 int nvm_submit_ppa(struct nvm_dev *dev, struct ppa_addr *ppa, int nr_ppas,
 405                                 int opcode, int flags, void *buf, int len)
 406 {
 407         struct nvm_rq rqd;
 408         int ret;
 409
 410         memset(&rqd, 0, sizeof(struct nvm_rq));
 411         ret = nvm_set_rqd_ppalist(dev, &rqd, ppa, nr_ppas);
 412         if (ret)
 413                 return ret;
 414
 415         ret = __nvm_submit_ppa(dev, &rqd, opcode, flags, buf, len);
 416
 417         nvm_free_rqd_ppalist(dev, &rqd);
 418
 419         return ret;
 420 }
 421 EXPORT_SYMBOL(nvm_submit_ppa);
 422
 423 static int nvm_init_slc_tbl(struct nvm_dev *dev, struct nvm_id_group *grp)
 424 {
 425         int i;
 426
 427         dev->lps_per_blk = dev->pgs_per_blk;
 428         dev->lptbl = kcalloc(dev->lps_per_blk, sizeof(int), GFP_KERNEL);
 429         if (!dev->lptbl)
 430                 return -ENOMEM;
 431
 432         /* Just a linear array */
 433         for (i = 0; i < dev->lps_per_blk; i++)
 434                 dev->lptbl[i] = i;
 435
 436         return 0;
 437 }
 438
 439 static int nvm_init_mlc_tbl(struct nvm_dev *dev, struct nvm_id_group *grp)
 440 {
 441         int i, p;
 442         struct nvm_id_lp_mlc *mlc = &grp->lptbl.mlc;
 443
 444         if (!mlc->num_pairs)
 445                 return 0;
 446
 447         dev->lps_per_blk = mlc->num_pairs;
 448         dev->lptbl = kcalloc(dev->lps_per_blk, sizeof(int), GFP_KERNEL);
 449         if (!dev->lptbl)
 450                 return -ENOMEM;
 451
 452         /* The lower page table encoding consists of a list of bytes, where each
 453          * has a lower and an upper half. The first half byte maintains the
 454          * increment value and every value after is an offset added to the
 455          * previous incrementation value */
 456         dev->lptbl[0] = mlc->pairs[0] & 0xF;
 457         for (i = 1; i < dev->lps_per_blk; i++) {
 458                 p = mlc->pairs[i >> 1];
 459                 if (i & 0x1) /* upper */
 460                         dev->lptbl[i] = dev->lptbl[i - 1] + ((p & 0xF0) >> 4);
 461                 else /* lower */
 462                         dev->lptbl[i] = dev->lptbl[i - 1] + (p & 0xF);
 463         }
 464
 465         return 0;
 466 }
 467
 468 static int nvm_core_init(struct nvm_dev *dev)
 469 {
 470         struct nvm_id *id = &dev->identity;
 471         struct nvm_id_group *grp = &id->groups[0];
 472
 473         /* device values */
 474         dev->nr_chnls = grp->num_ch;
 475         dev->luns_per_chnl = grp->num_lun;
 476         dev->pgs_per_blk = grp->num_pg;
 477         dev->blks_per_lun = grp->num_blk;
 478         dev->nr_planes = grp->num_pln;
 479         dev->sec_size = grp->csecs;
 480         dev->oob_size = grp->sos;
 481         dev->sec_per_pg = grp->fpg_sz / grp->csecs;
 482         dev->mccap = grp->mccap;
 483         memcpy(&dev->ppaf, &id->ppaf, sizeof(struct nvm_addr_format));
 484
 485         dev->plane_mode = NVM_PLANE_SINGLE;
 486         dev->max_rq_size = dev->ops->max_phys_sect * dev->sec_size;
 487
 488         if (grp->mtype != 0) {
 489                 pr_err("nvm: memory type not supported\n");
 490                 return -EINVAL;
 491         }
 492
 493         switch (grp->fmtype) {
 494         case NVM_ID_FMTYPE_SLC:
 495                 if (nvm_init_slc_tbl(dev, grp))
 496                         return -ENOMEM;
 497                 break;
 498         case NVM_ID_FMTYPE_MLC:
 499                 if (nvm_init_mlc_tbl(dev, grp))
 500                         return -ENOMEM;
 501                 break;
 502         default:
 503                 pr_err("nvm: flash type not supported\n");
 504                 return -EINVAL;
 505         }
 506
 507         if (!dev->lps_per_blk)
 508                 pr_info("nvm: lower page programming table missing\n");
 509
 510         if (grp->mpos & 0x020202)
 511                 dev->plane_mode = NVM_PLANE_DOUBLE;
 512         if (grp->mpos & 0x040404)
 513                 dev->plane_mode = NVM_PLANE_QUAD;
 514
 515         /* calculated values */
 516         dev->sec_per_pl = dev->sec_per_pg * dev->nr_planes;
 517         dev->sec_per_blk = dev->sec_per_pl * dev->pgs_per_blk;
 518         dev->sec_per_lun = dev->sec_per_blk * dev->blks_per_lun;
 519         dev->nr_luns = dev->luns_per_chnl * dev->nr_chnls;
 520
 521         dev->total_secs = dev->nr_luns * dev->sec_per_lun;
 522         dev->lun_map = kcalloc(BITS_TO_LONGS(dev->nr_luns),
 523                                         sizeof(unsigned long), GFP_KERNEL);
 524         if (!dev->lun_map)
 525                 return -ENOMEM;
 526         INIT_LIST_HEAD(&dev->online_targets);
 527         mutex_init(&dev->mlock);
 528         spin_lock_init(&dev->lock);
 529
 530         return 0;
 531 }
 532
 533 static void nvm_free(struct nvm_dev *dev)
 534 {
 535         if (!dev)
 536                 return;
 537
 538         if (dev->mt)
 539                 dev->mt->unregister_mgr(dev);
 540
 541         kfree(dev->lptbl);
 542 }
 543
 544 static int nvm_init(struct nvm_dev *dev)
 545 {
 546         int ret = -EINVAL;
 547
 548         if (!dev->q || !dev->ops)
 549                 return ret;
 550
 551         if (dev->ops->identity(dev, &dev->identity)) {
 552                 pr_err("nvm: device could not be identified\n");
 553                 goto err;
 554         }
 555
 556         pr_debug("nvm: ver:%x nvm_vendor:%x groups:%u\n",
 557                         dev->identity.ver_id, dev->identity.vmnt,
 558                                                         dev->identity.cgrps);
 559
 560         if (dev->identity.ver_id != 1) {
 561                 pr_err("nvm: device not supported by kernel.");
 562                 goto err;
 563         }
 564
 565         if (dev->identity.cgrps != 1) {
 566                 pr_err("nvm: only one group configuration supported.");
 567                 goto err;
 568         }
 569
 570         ret = nvm_core_init(dev);
 571         if (ret) {
 572                 pr_err("nvm: could not initialize core structures.\n");
 573                 goto err;
 574         }
 575
 576         pr_info("nvm: registered %s [%u/%u/%u/%u/%u/%u]\n",
 577                         dev->name, dev->sec_per_pg, dev->nr_planes,
 578                         dev->pgs_per_blk, dev->blks_per_lun, dev->nr_luns,
 579                         dev->nr_chnls);
 580         return 0;
 581 err:
 582         pr_err("nvm: failed to initialize nvm\n");
 583         return ret;
 584 }
 585
 586 static void nvm_exit(struct nvm_dev *dev)
 587 {
 588         if (dev->ppalist_pool)
 589                 dev->ops->destroy_dma_pool(dev->ppalist_pool);
 590         nvm_free(dev);
 591
 592         pr_info("nvm: successfully unloaded\n");
 593 }
 594
 595 int nvm_register(struct request_queue *q, char *disk_name,
 596                                                         struct nvm_dev_ops *ops)
 597 {
 598         struct nvm_dev *dev;
 599         int ret;
 600
 601         if (!ops->identity)
 602                 return -EINVAL;
 603
 604         dev = kzalloc(sizeof(struct nvm_dev), GFP_KERNEL);
 605         if (!dev)
 606                 return -ENOMEM;
 607
 608         dev->q = q;
 609         dev->ops = ops;
 610         strncpy(dev->name, disk_name, DISK_NAME_LEN);
 611
 612         ret = nvm_init(dev);
 613         if (ret)
 614                 goto err_init;
 615
 616         if (dev->ops->max_phys_sect > 256) {
 617                 pr_info("nvm: max sectors supported is 256.\n");
 618                 ret = -EINVAL;
 619                 goto err_init;
 620         }
 621
 622         if (dev->ops->max_phys_sect > 1) {
 623                 dev->ppalist_pool = dev->ops->create_dma_pool(dev, "ppalist");
 624                 if (!dev->ppalist_pool) {
 625                         pr_err("nvm: could not create ppa pool\n");
 626                         ret = -ENOMEM;
 627                         goto err_init;
 628                 }
 629         }
 630
 631         if (dev->identity.cap & NVM_ID_DCAP_BBLKMGMT) {
 632                 ret = nvm_get_sysblock(dev, &dev->sb);
 633                 if (!ret)
 634                         pr_err("nvm: device not initialized.\n");
 635                 else if (ret < 0)
 636                         pr_err("nvm: err (%d) on device initialization\n", ret);
 637         }
 638
 639         /* register device with a supported media manager */
 640         down_write(&nvm_lock);
 641         if (ret > 0)
 642                 dev->mt = nvm_init_mgr(dev);
 643         list_add(&dev->devices, &nvm_devices);
 644         up_write(&nvm_lock);
 645
 646         return 0;
 647 err_init:
 648         kfree(dev->lun_map);
 649         kfree(dev);
 650         return ret;
 651 }
 652 EXPORT_SYMBOL(nvm_register);
 653
 654 void nvm_unregister(char *disk_name)
 655 {
 656         struct nvm_dev *dev;
 657
 658         down_write(&nvm_lock);
 659         dev = nvm_find_nvm_dev(disk_name);
 660         if (!dev) {
 661                 pr_err("nvm: could not find device %s to unregister\n",
 662                                                                 disk_name);
 663                 up_write(&nvm_lock);
 664                 return;
 665         }
 666
 667         list_del(&dev->devices);
 668         up_write(&nvm_lock);
 669
 670         nvm_exit(dev);
 671         kfree(dev->lun_map);
 672         kfree(dev);
 673 }
 674 EXPORT_SYMBOL(nvm_unregister);
 675
 676 static const struct block_device_operations nvm_fops = {
 677         .owner          = THIS_MODULE,
 678 };
 679
 680 static int nvm_create_target(struct nvm_dev *dev,
 681                                                 struct nvm_ioctl_create *create)
 682 {
 683         struct nvm_ioctl_create_simple *s = &create->conf.s;
 684         struct request_queue *tqueue;
 685         struct gendisk *tdisk;
 686         struct nvm_tgt_type *tt;
 687         struct nvm_target *t;
 688         void *targetdata;
 689
 690         if (!dev->mt) {
 691                 pr_info("nvm: device has no media manager registered.\n");
 692                 return -ENODEV;
 693         }
 694
 695         down_write(&nvm_lock);
 696         tt = nvm_find_target_type(create->tgttype);
 697         if (!tt) {
 698                 pr_err("nvm: target type %s not found\n", create->tgttype);
 699                 up_write(&nvm_lock);
 700                 return -EINVAL;
 701         }
 702
 703         list_for_each_entry(t, &dev->online_targets, list) {
 704                 if (!strcmp(create->tgtname, t->disk->disk_name)) {
 705                         pr_err("nvm: target name already exists.\n");
 706                         up_write(&nvm_lock);
 707                         return -EINVAL;
 708                 }
 709         }
 710         up_write(&nvm_lock);
 711
 712         t = kmalloc(sizeof(struct nvm_target), GFP_KERNEL);
 713         if (!t)
 714                 return -ENOMEM;
 715
 716         tqueue = blk_alloc_queue_node(GFP_KERNEL, dev->q->node);
 717         if (!tqueue)
 718                 goto err_t;
 719         blk_queue_make_request(tqueue, tt->make_rq);
 720
 721         tdisk = alloc_disk(0);
 722         if (!tdisk)
 723                 goto err_queue;
 724
 725         sprintf(tdisk->disk_name, "%s", create->tgtname);
 726         tdisk->flags = GENHD_FL_EXT_DEVT;
 727         tdisk->major = 0;
 728         tdisk->first_minor = 0;
 729         tdisk->fops = &nvm_fops;
 730         tdisk->queue = tqueue;
 731
 732         targetdata = tt->init(dev, tdisk, s->lun_begin, s->lun_end);
 733         if (IS_ERR(targetdata))
 734                 goto err_init;
 735
 736         tdisk->private_data = targetdata;
 737         tqueue->queuedata = targetdata;
 738
 739         blk_queue_max_hw_sectors(tqueue, 8 * dev->ops->max_phys_sect);
 740
 741         set_capacity(tdisk, tt->capacity(targetdata));
 742         add_disk(tdisk);
 743
 744         t->type = tt;
 745         t->disk = tdisk;
 746
 747         down_write(&nvm_lock);
 748         list_add_tail(&t->list, &dev->online_targets);
 749         up_write(&nvm_lock);
 750
 751         return 0;
 752 err_init:
 753         put_disk(tdisk);
 754 err_queue:
 755         blk_cleanup_queue(tqueue);
 756 err_t:
 757         kfree(t);
 758         return -ENOMEM;
 759 }
 760
 761 static void nvm_remove_target(struct nvm_target *t)
 762 {
 763         struct nvm_tgt_type *tt = t->type;
 764         struct gendisk *tdisk = t->disk;
 765         struct request_queue *q = tdisk->queue;
 766
 767         lockdep_assert_held(&nvm_lock);
 768
 769         del_gendisk(tdisk);
 770         blk_cleanup_queue(q);
 771
 772         if (tt->exit)
 773                 tt->exit(tdisk->private_data);
 774
 775         put_disk(tdisk);
 776
 777         list_del(&t->list);
 778         kfree(t);
 779 }
 780
 781 static int __nvm_configure_create(struct nvm_ioctl_create *create)
 782 {
 783         struct nvm_dev *dev;
 784         struct nvm_ioctl_create_simple *s;
 785
 786         down_write(&nvm_lock);
 787         dev = nvm_find_nvm_dev(create->dev);
 788         up_write(&nvm_lock);
 789         if (!dev) {
 790                 pr_err("nvm: device not found\n");
 791                 return -EINVAL;
 792         }
 793
 794         if (create->conf.type != NVM_CONFIG_TYPE_SIMPLE) {
 795                 pr_err("nvm: config type not valid\n");
 796                 return -EINVAL;
 797         }
 798         s = &create->conf.s;
 799
 800         if (s->lun_begin > s->lun_end || s->lun_end > dev->nr_luns) {
 801                 pr_err("nvm: lun out of bound (%u:%u > %u)\n",
 802                         s->lun_begin, s->lun_end, dev->nr_luns);
 803                 return -EINVAL;
 804         }
 805
 806         return nvm_create_target(dev, create);
 807 }
 808
 809 static int __nvm_configure_remove(struct nvm_ioctl_remove *remove)
 810 {
 811         struct nvm_target *t = NULL;
 812         struct nvm_dev *dev;
 813         int ret = -1;
 814
 815         down_write(&nvm_lock);
 816         list_for_each_entry(dev, &nvm_devices, devices)
 817                 list_for_each_entry(t, &dev->online_targets, list) {
 818                         if (!strcmp(remove->tgtname, t->disk->disk_name)) {
 819                                 nvm_remove_target(t);
 820                                 ret = 0;
 821                                 break;
 822                         }
 823                 }
 824         up_write(&nvm_lock);
 825
 826         if (ret) {
 827                 pr_err("nvm: target \"%s\" doesn't exist.\n", remove->tgtname);
 828                 return -EINVAL;
 829         }
 830
 831         return 0;
 832 }
 833
 834 #ifdef CONFIG_NVM_DEBUG
 835 static int nvm_configure_show(const char *val)
 836 {
 837         struct nvm_dev *dev;
 838         char opcode, devname[DISK_NAME_LEN];
 839         int ret;
 840
 841         ret = sscanf(val, "%c %32s", &opcode, devname);
 842         if (ret != 2) {
 843                 pr_err("nvm: invalid command. Use \"opcode devicename\".\n");
 844                 return -EINVAL;
 845         }
 846
 847         down_write(&nvm_lock);
 848         dev = nvm_find_nvm_dev(devname);
 849         up_write(&nvm_lock);
 850         if (!dev) {
 851                 pr_err("nvm: device not found\n");
 852                 return -EINVAL;
 853         }
 854
 855         if (!dev->mt)
 856                 return 0;
 857
 858         dev->mt->lun_info_print(dev);
 859
 860         return 0;
 861 }
 862
 863 static int nvm_configure_remove(const char *val)
 864 {
 865         struct nvm_ioctl_remove remove;
 866         char opcode;
 867         int ret;
 868
 869         ret = sscanf(val, "%c %256s", &opcode, remove.tgtname);
 870         if (ret != 2) {
 871                 pr_err("nvm: invalid command. Use \"d targetname\".\n");
 872                 return -EINVAL;
 873         }
 874
 875         remove.flags = 0;
 876
 877         return __nvm_configure_remove(&remove);
 878 }
 879
 880 static int nvm_configure_create(const char *val)
 881 {
 882         struct nvm_ioctl_create create;
 883         char opcode;
 884         int lun_begin, lun_end, ret;
 885
 886         ret = sscanf(val, "%c %256s %256s %48s %u:%u", &opcode, create.dev,
 887                                                 create.tgtname, create.tgttype,
 888                                                 &lun_begin, &lun_end);
 889         if (ret != 6) {
 890                 pr_err("nvm: invalid command. Use \"opcode device name tgttype lun_begin:lun_end\".\n");
 891                 return -EINVAL;
 892         }
 893
 894         create.flags = 0;
 895         create.conf.type = NVM_CONFIG_TYPE_SIMPLE;
 896         create.conf.s.lun_begin = lun_begin;
 897         create.conf.s.lun_end = lun_end;
 898
 899         return __nvm_configure_create(&create);
 900 }
 901
 902
 903 /* Exposes administrative interface through /sys/module/lnvm/configure_by_str */
 904 static int nvm_configure_by_str_event(const char *val,
 905                                         const struct kernel_param *kp)
 906 {
 907         char opcode;
 908         int ret;
 909
 910         ret = sscanf(val, "%c", &opcode);
 911         if (ret != 1) {
 912                 pr_err("nvm: string must have the format of \"cmd ...\"\n");
 913                 return -EINVAL;
 914         }
 915
 916         switch (opcode) {
 917         case 'a':
 918                 return nvm_configure_create(val);
 919         case 'd':
 920                 return nvm_configure_remove(val);
 921         case 's':
 922                 return nvm_configure_show(val);
 923         default:
 924                 pr_err("nvm: invalid command\n");
 925                 return -EINVAL;
 926         }
 927
 928         return 0;
 929 }
 930
 931 static int nvm_configure_get(char *buf, const struct kernel_param *kp)
 932 {
 933         int sz;
 934         struct nvm_dev *dev;
 935
 936         sz = sprintf(buf, "available devices:\n");
 937         down_write(&nvm_lock);
 938         list_for_each_entry(dev, &nvm_devices, devices) {
 939                 if (sz > 4095 - DISK_NAME_LEN - 2)
 940                         break;
 941                 sz += sprintf(buf + sz, " %32s\n", dev->name);
 942         }
 943         up_write(&nvm_lock);
 944
 945         return sz;
 946 }
 947
 948 static const struct kernel_param_ops nvm_configure_by_str_event_param_ops = {
 949         .set    = nvm_configure_by_str_event,
 950         .get    = nvm_configure_get,
 951 };
 952
 953 #undef MODULE_PARAM_PREFIX
 954 #define MODULE_PARAM_PREFIX     "lnvm."
 955
 956 module_param_cb(configure_debug, &nvm_configure_by_str_event_param_ops, NULL,
 957                                                                         0644);
 958
 959 #endif /* CONFIG_NVM_DEBUG */
 960
 961 static long nvm_ioctl_info(struct file *file, void __user *arg)
 962 {
 963         struct nvm_ioctl_info *info;
 964         struct nvm_tgt_type *tt;
 965         int tgt_iter = 0;
 966
 967         if (!capable(CAP_SYS_ADMIN))
 968                 return -EPERM;
 969
 970         info = memdup_user(arg, sizeof(struct nvm_ioctl_info));
 971         if (IS_ERR(info))
 972                 return -EFAULT;
 973
 974         info->version[0] = NVM_VERSION_MAJOR;
 975         info->version[1] = NVM_VERSION_MINOR;
 976         info->version[2] = NVM_VERSION_PATCH;
 977
 978         down_write(&nvm_lock);
 979         list_for_each_entry(tt, &nvm_targets, list) {
 980                 struct nvm_ioctl_info_tgt *tgt = &info->tgts[tgt_iter];
 981
 982                 tgt->version[0] = tt->version[0];
 983                 tgt->version[1] = tt->version[1];
 984                 tgt->version[2] = tt->version[2];
 985                 strncpy(tgt->tgtname, tt->name, NVM_TTYPE_NAME_MAX);
 986
 987                 tgt_iter++;
 988         }
 989
 990         info->tgtsize = tgt_iter;
 991         up_write(&nvm_lock);
 992
 993         if (copy_to_user(arg, info, sizeof(struct nvm_ioctl_info))) {
 994                 kfree(info);
 995                 return -EFAULT;
 996         }
 997
 998         kfree(info);
 999         return 0;
1000 }
1001
1002 static long nvm_ioctl_get_devices(struct file *file, void __user *arg)
1003 {
1004         struct nvm_ioctl_get_devices *devices;
1005         struct nvm_dev *dev;
1006         int i = 0;
1007
1008         if (!capable(CAP_SYS_ADMIN))
1009                 return -EPERM;
1010
1011         devices = kzalloc(sizeof(struct nvm_ioctl_get_devices), GFP_KERNEL);
1012         if (!devices)
1013                 return -ENOMEM;
1014
1015         down_write(&nvm_lock);
1016         list_for_each_entry(dev, &nvm_devices, devices) {
1017                 struct nvm_ioctl_device_info *info = &devices->info[i];
1018
1019                 sprintf(info->devname, "%s", dev->name);
1020                 if (dev->mt) {
1021                         info->bmversion[0] = dev->mt->version[0];
1022                         info->bmversion[1] = dev->mt->version[1];
1023                         info->bmversion[2] = dev->mt->version[2];
1024                         sprintf(info->bmname, "%s", dev->mt->name);
1025                 } else {
1026                         sprintf(info->bmname, "none");
1027                 }
1028
1029                 i++;
1030                 if (i > 31) {
1031                         pr_err("nvm: max 31 devices can be reported.\n");
1032                         break;
1033                 }
1034         }
1035         up_write(&nvm_lock);
1036
1037         devices->nr_devices = i;
1038
1039         if (copy_to_user(arg, devices,
1040                          sizeof(struct nvm_ioctl_get_devices))) {
1041                 kfree(devices);
1042                 return -EFAULT;
1043         }
1044
1045         kfree(devices);
1046         return 0;
1047 }
1048
1049 static long nvm_ioctl_dev_create(struct file *file, void __user *arg)
1050 {
1051         struct nvm_ioctl_create create;
1052
1053         if (!capable(CAP_SYS_ADMIN))
1054                 return -EPERM;
1055
1056         if (copy_from_user(&create, arg, sizeof(struct nvm_ioctl_create)))
1057                 return -EFAULT;
1058
1059         create.dev[DISK_NAME_LEN - 1] = '\0';
1060         create.tgttype[NVM_TTYPE_NAME_MAX - 1] = '\0';
1061         create.tgtname[DISK_NAME_LEN - 1] = '\0';
1062
1063         if (create.flags != 0) {
1064                 pr_err("nvm: no flags supported\n");
1065                 return -EINVAL;
1066         }
1067
1068         return __nvm_configure_create(&create);
1069 }
1070
1071 static long nvm_ioctl_dev_remove(struct file *file, void __user *arg)
1072 {
1073         struct nvm_ioctl_remove remove;
1074
1075         if (!capable(CAP_SYS_ADMIN))
1076                 return -EPERM;
1077
1078         if (copy_from_user(&remove, arg, sizeof(struct nvm_ioctl_remove)))
1079                 return -EFAULT;
1080
1081         remove.tgtname[DISK_NAME_LEN - 1] = '\0';
1082
1083         if (remove.flags != 0) {
1084                 pr_err("nvm: no flags supported\n");
1085                 return -EINVAL;
1086         }
1087
1088         return __nvm_configure_remove(&remove);
1089 }
1090
1091 static void nvm_setup_nvm_sb_info(struct nvm_sb_info *info)
1092 {
1093         info->seqnr = 1;
1094         info->erase_cnt = 0;
1095         info->version = 1;
1096 }
1097
1098 static long __nvm_ioctl_dev_init(struct nvm_ioctl_dev_init *init)
1099 {
1100         struct nvm_dev *dev;
1101         struct nvm_sb_info info;
1102         int ret;
1103
1104         down_write(&nvm_lock);
1105         dev = nvm_find_nvm_dev(init->dev);
1106         up_write(&nvm_lock);
1107         if (!dev) {
1108                 pr_err("nvm: device not found\n");
1109                 return -EINVAL;
1110         }
1111
1112         nvm_setup_nvm_sb_info(&info);
1113
1114         strncpy(info.mmtype, init->mmtype, NVM_MMTYPE_LEN);
1115         info.fs_ppa.ppa = -1;
1116
1117         if (dev->identity.cap & NVM_ID_DCAP_BBLKMGMT) {
1118                 ret = nvm_init_sysblock(dev, &info);
1119                 if (ret)
1120                         return ret;
1121         }
1122
1123         memcpy(&dev->sb, &info, sizeof(struct nvm_sb_info));
1124
1125         down_write(&nvm_lock);
1126         dev->mt = nvm_init_mgr(dev);
1127         up_write(&nvm_lock);
1128
1129         return 0;
1130 }
1131
1132 static long nvm_ioctl_dev_init(struct file *file, void __user *arg)
1133 {
1134         struct nvm_ioctl_dev_init init;
1135
1136         if (!capable(CAP_SYS_ADMIN))
1137                 return -EPERM;
1138
1139         if (copy_from_user(&init, arg, sizeof(struct nvm_ioctl_dev_init)))
1140                 return -EFAULT;
1141
1142         if (init.flags != 0) {
1143                 pr_err("nvm: no flags supported\n");
1144                 return -EINVAL;
1145         }
1146
1147         init.dev[DISK_NAME_LEN - 1] = '\0';
1148
1149         return __nvm_ioctl_dev_init(&init);
1150 }
1151
1152 static long nvm_ioctl_dev_factory(struct file *file, void __user *arg)
1153 {
1154         struct nvm_ioctl_dev_factory fact;
1155         struct nvm_dev *dev;
1156
1157         if (!capable(CAP_SYS_ADMIN))
1158                 return -EPERM;
1159
1160         if (copy_from_user(&fact, arg, sizeof(struct nvm_ioctl_dev_factory)))
1161                 return -EFAULT;
1162
1163         fact.dev[DISK_NAME_LEN - 1] = '\0';
1164
1165         if (fact.flags & ~(NVM_FACTORY_NR_BITS - 1))
1166                 return -EINVAL;
1167
1168         down_write(&nvm_lock);
1169         dev = nvm_find_nvm_dev(fact.dev);
1170         up_write(&nvm_lock);
1171         if (!dev) {
1172                 pr_err("nvm: device not found\n");
1173                 return -EINVAL;
1174         }
1175
1176         if (dev->mt) {
1177                 dev->mt->unregister_mgr(dev);
1178                 dev->mt = NULL;
1179         }
1180
1181         if (dev->identity.cap & NVM_ID_DCAP_BBLKMGMT)
1182                 return nvm_dev_factory(dev, fact.flags);
1183
1184         return 0;
1185 }
1186
1187 static long nvm_ctl_ioctl(struct file *file, uint cmd, unsigned long arg)
1188 {
1189         void __user *argp = (void __user *)arg;
1190
1191         switch (cmd) {
1192         case NVM_INFO:
1193                 return nvm_ioctl_info(file, argp);
1194         case NVM_GET_DEVICES:
1195                 return nvm_ioctl_get_devices(file, argp);
1196         case NVM_DEV_CREATE:
1197                 return nvm_ioctl_dev_create(file, argp);
1198         case NVM_DEV_REMOVE:
1199                 return nvm_ioctl_dev_remove(file, argp);
1200         case NVM_DEV_INIT:
1201                 return nvm_ioctl_dev_init(file, argp);
1202         case NVM_DEV_FACTORY:
1203                 return nvm_ioctl_dev_factory(file, argp);
1204         }
1205         return 0;
1206 }
1207
1208 static const struct file_operations _ctl_fops = {
1209         .open = nonseekable_open,
1210         .unlocked_ioctl = nvm_ctl_ioctl,
1211         .owner = THIS_MODULE,
1212         .llseek  = noop_llseek,
1213 };
1214
1215 static struct miscdevice _nvm_misc = {
1216         .minor          = MISC_DYNAMIC_MINOR,
1217         .name           = "lightnvm",
1218         .nodename       = "lightnvm/control",
1219         .fops           = &_ctl_fops,
1220 };
1221
1222 MODULE_ALIAS_MISCDEV(MISC_DYNAMIC_MINOR);
1223
1224 static int __init nvm_mod_init(void)
1225 {
1226         int ret;
1227
1228         ret = misc_register(&_nvm_misc);
1229         if (ret)
1230                 pr_err("nvm: misc_register failed for control device");
1231
1232         return ret;
1233 }
1234
1235 static void __exit nvm_mod_exit(void)
1236 {
1237         misc_deregister(&_nvm_misc);
1238 }
1239
1240 MODULE_AUTHOR("Matias Bjorling <m@bjorling.me>");
1241 MODULE_LICENSE("GPL v2");
1242 MODULE_VERSION("0.1");
1243 module_init(nvm_mod_init);
1244 module_exit(nvm_mod_exit);