drivers/lightnvm/pblk-read.c

   1 /*
   2  * Copyright (C) 2016 CNEX Labs
   3  * Initial release: Javier Gonzalez <javier@cnexlabs.com>
   4  *                  Matias Bjorling <matias@cnexlabs.com>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License version
   8  * 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * pblk-read.c - pblk's read path
  16  */
  17
  18 #include "pblk.h"
  19
  20 /*
  21  * There is no guarantee that the value read from cache has not been updated and
  22  * resides at another location in the cache. We guarantee though that if the
  23  * value is read from the cache, it belongs to the mapped lba. In order to
  24  * guarantee and order between writes and reads are ordered, a flush must be
  25  * issued.
  26  */
  27 static int pblk_read_from_cache(struct pblk *pblk, struct bio *bio,
  28                                 sector_t lba, struct ppa_addr ppa,
  29                                 int bio_iter, bool advanced_bio)
  30 {
  31 #ifdef CONFIG_NVM_DEBUG
  32         /* Callers must ensure that the ppa points to a cache address */
  33         BUG_ON(pblk_ppa_empty(ppa));
  34         BUG_ON(!pblk_addr_in_cache(ppa));
  35 #endif
  36
  37         return pblk_rb_copy_to_bio(&pblk->rwb, bio, lba, ppa,
  38                                                 bio_iter, advanced_bio);
  39 }
  40
  41 static void pblk_read_ppalist_rq(struct pblk *pblk, struct nvm_rq *rqd,
  42                                  struct bio *bio, sector_t blba,
  43                                  unsigned long *read_bitmap)
  44 {
  45         struct pblk_sec_meta *meta_list = rqd->meta_list;
  46         struct ppa_addr ppas[PBLK_MAX_REQ_ADDRS];
  47         int nr_secs = rqd->nr_ppas;
  48         bool advanced_bio = false;
  49         int i, j = 0;
  50
  51         pblk_lookup_l2p_seq(pblk, ppas, blba, nr_secs);
  52
  53         for (i = 0; i < nr_secs; i++) {
  54                 struct ppa_addr p = ppas[i];
  55                 sector_t lba = blba + i;
  56
  57 retry:
  58                 if (pblk_ppa_empty(p)) {
  59                         WARN_ON(test_and_set_bit(i, read_bitmap));
  60                         meta_list[i].lba = cpu_to_le64(ADDR_EMPTY);
  61
  62                         if (unlikely(!advanced_bio)) {
  63                                 bio_advance(bio, (i) * PBLK_EXPOSED_PAGE_SIZE);
  64                                 advanced_bio = true;
  65                         }
  66
  67                         goto next;
  68                 }
  69
  70                 /* Try to read from write buffer. The address is later checked
  71                  * on the write buffer to prevent retrieving overwritten data.
  72                  */
  73                 if (pblk_addr_in_cache(p)) {
  74                         if (!pblk_read_from_cache(pblk, bio, lba, p, i,
  75                                                                 advanced_bio)) {
  76                                 pblk_lookup_l2p_seq(pblk, &p, lba, 1);
  77                                 goto retry;
  78                         }
  79                         WARN_ON(test_and_set_bit(i, read_bitmap));
  80                         meta_list[i].lba = cpu_to_le64(lba);
  81                         advanced_bio = true;
  82 #ifdef CONFIG_NVM_DEBUG
  83                         atomic_long_inc(&pblk->cache_reads);
  84 #endif
  85                 } else {
  86                         /* Read from media non-cached sectors */
  87                         rqd->ppa_list[j++] = p;
  88                 }
  89
  90 next:
  91                 if (advanced_bio)
  92                         bio_advance(bio, PBLK_EXPOSED_PAGE_SIZE);
  93         }
  94
  95         if (pblk_io_aligned(pblk, nr_secs))
  96                 rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_SEQUENTIAL);
  97         else
  98                 rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
  99
 100 #ifdef CONFIG_NVM_DEBUG
 101         atomic_long_add(nr_secs, &pblk->inflight_reads);
 102 #endif
 103 }
 104
 105
 106 static void pblk_read_check_seq(struct pblk *pblk, struct nvm_rq *rqd,
 107                                 sector_t blba)
 108 {
 109         struct pblk_sec_meta *meta_lba_list = rqd->meta_list;
 110         int nr_lbas = rqd->nr_ppas;
 111         int i;
 112
 113         for (i = 0; i < nr_lbas; i++) {
 114                 u64 lba = le64_to_cpu(meta_lba_list[i].lba);
 115
 116                 if (lba == ADDR_EMPTY)
 117                         continue;
 118
 119                 if (lba != blba + i) {
 120 #ifdef CONFIG_NVM_DEBUG
 121                         struct ppa_addr *p;
 122
 123                         p = (nr_lbas == 1) ? &rqd->ppa_list[i] : &rqd->ppa_addr;
 124                         print_ppa(&pblk->dev->geo, p, "seq", i);
 125 #endif
 126                         pr_err("pblk: corrupted read LBA (%llu/%llu)\n",
 127                                                         lba, (u64)blba + i);
 128                         WARN_ON(1);
 129                 }
 130         }
 131 }
 132
 133 /*
 134  * There can be holes in the lba list.
 135  */
 136 static void pblk_read_check_rand(struct pblk *pblk, struct nvm_rq *rqd,
 137                                  u64 *lba_list, int nr_lbas)
 138 {
 139         struct pblk_sec_meta *meta_lba_list = rqd->meta_list;
 140         int i, j;
 141
 142         for (i = 0, j = 0; i < nr_lbas; i++) {
 143                 u64 lba = lba_list[i];
 144                 u64 meta_lba;
 145
 146                 if (lba == ADDR_EMPTY)
 147                         continue;
 148
 149                 meta_lba = le64_to_cpu(meta_lba_list[j].lba);
 150
 151                 if (lba != meta_lba) {
 152 #ifdef CONFIG_NVM_DEBUG
 153                         struct ppa_addr *p;
 154                         int nr_ppas = rqd->nr_ppas;
 155
 156                         p = (nr_ppas == 1) ? &rqd->ppa_list[j] : &rqd->ppa_addr;
 157                         print_ppa(&pblk->dev->geo, p, "seq", j);
 158 #endif
 159                         pr_err("pblk: corrupted read LBA (%llu/%llu)\n",
 160                                                                 lba, meta_lba);
 161                         WARN_ON(1);
 162                 }
 163
 164                 j++;
 165         }
 166
 167         WARN_ONCE(j != rqd->nr_ppas, "pblk: corrupted random request\n");
 168 }
 169
 170 static void pblk_read_put_rqd_kref(struct pblk *pblk, struct nvm_rq *rqd)
 171 {
 172         struct ppa_addr *ppa_list;
 173         int i;
 174
 175         ppa_list = (rqd->nr_ppas > 1) ? rqd->ppa_list : &rqd->ppa_addr;
 176
 177         for (i = 0; i < rqd->nr_ppas; i++) {
 178                 struct ppa_addr ppa = ppa_list[i];
 179                 struct pblk_line *line;
 180
 181                 line = &pblk->lines[pblk_ppa_to_line(ppa)];
 182                 kref_put(&line->ref, pblk_line_put_wq);
 183         }
 184 }
 185
 186 static void pblk_end_user_read(struct bio *bio)
 187 {
 188 #ifdef CONFIG_NVM_DEBUG
 189         WARN_ONCE(bio->bi_status, "pblk: corrupted read bio\n");
 190 #endif
 191         bio_endio(bio);
 192 }
 193
 194 static void __pblk_end_io_read(struct pblk *pblk, struct nvm_rq *rqd,
 195                                bool put_line)
 196 {
 197         struct nvm_tgt_dev *dev = pblk->dev;
 198         struct pblk_g_ctx *r_ctx = nvm_rq_to_pdu(rqd);
 199         struct bio *int_bio = rqd->bio;
 200         unsigned long start_time = r_ctx->start_time;
 201
 202         generic_end_io_acct(dev->q, READ, &pblk->disk->part0, start_time);
 203
 204         if (rqd->error)
 205                 pblk_log_read_err(pblk, rqd);
 206
 207         pblk_read_check_seq(pblk, rqd, r_ctx->lba);
 208
 209         if (int_bio)
 210                 bio_put(int_bio);
 211
 212         if (put_line)
 213                 pblk_read_put_rqd_kref(pblk, rqd);
 214
 215 #ifdef CONFIG_NVM_DEBUG
 216         atomic_long_add(rqd->nr_ppas, &pblk->sync_reads);
 217         atomic_long_sub(rqd->nr_ppas, &pblk->inflight_reads);
 218 #endif
 219
 220         pblk_free_rqd(pblk, rqd, PBLK_READ);
 221         atomic_dec(&pblk->inflight_io);
 222 }
 223
 224 static void pblk_end_io_read(struct nvm_rq *rqd)
 225 {
 226         struct pblk *pblk = rqd->private;
 227         struct pblk_g_ctx *r_ctx = nvm_rq_to_pdu(rqd);
 228         struct bio *bio = (struct bio *)r_ctx->private;
 229
 230         pblk_end_user_read(bio);
 231         __pblk_end_io_read(pblk, rqd, true);
 232 }
 233
 234 static int pblk_partial_read(struct pblk *pblk, struct nvm_rq *rqd,
 235                              struct bio *orig_bio, unsigned int bio_init_idx,
 236                              unsigned long *read_bitmap)
 237 {
 238         struct pblk_sec_meta *meta_list = rqd->meta_list;
 239         struct bio *new_bio;
 240         struct bio_vec src_bv, dst_bv;
 241         void *ppa_ptr = NULL;
 242         void *src_p, *dst_p;
 243         dma_addr_t dma_ppa_list = 0;
 244         __le64 *lba_list_mem, *lba_list_media;
 245         int nr_secs = rqd->nr_ppas;
 246         int nr_holes = nr_secs - bitmap_weight(read_bitmap, nr_secs);
 247         int i, ret, hole;
 248
 249         /* Re-use allocated memory for intermediate lbas */
 250         lba_list_mem = (((void *)rqd->ppa_list) + pblk_dma_ppa_size);
 251         lba_list_media = (((void *)rqd->ppa_list) + 2 * pblk_dma_ppa_size);
 252
 253         new_bio = bio_alloc(GFP_KERNEL, nr_holes);
 254
 255         if (pblk_bio_add_pages(pblk, new_bio, GFP_KERNEL, nr_holes))
 256                 goto fail_add_pages;
 257
 258         if (nr_holes != new_bio->bi_vcnt) {
 259                 pr_err("pblk: malformed bio\n");
 260                 goto fail;
 261         }
 262
 263         for (i = 0; i < nr_secs; i++)
 264                 lba_list_mem[i] = meta_list[i].lba;
 265
 266         new_bio->bi_iter.bi_sector = 0; /* internal bio */
 267         bio_set_op_attrs(new_bio, REQ_OP_READ, 0);
 268
 269         rqd->bio = new_bio;
 270         rqd->nr_ppas = nr_holes;
 271         rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
 272
 273         if (unlikely(nr_holes == 1)) {
 274                 ppa_ptr = rqd->ppa_list;
 275                 dma_ppa_list = rqd->dma_ppa_list;
 276                 rqd->ppa_addr = rqd->ppa_list[0];
 277         }
 278
 279         ret = pblk_submit_io_sync(pblk, rqd);
 280         if (ret) {
 281                 bio_put(rqd->bio);
 282                 pr_err("pblk: sync read IO submission failed\n");
 283                 goto fail;
 284         }
 285
 286         if (rqd->error) {
 287                 atomic_long_inc(&pblk->read_failed);
 288 #ifdef CONFIG_NVM_DEBUG
 289                 pblk_print_failed_rqd(pblk, rqd, rqd->error);
 290 #endif
 291         }
 292
 293         if (unlikely(nr_holes == 1)) {
 294                 struct ppa_addr ppa;
 295
 296                 ppa = rqd->ppa_addr;
 297                 rqd->ppa_list = ppa_ptr;
 298                 rqd->dma_ppa_list = dma_ppa_list;
 299                 rqd->ppa_list[0] = ppa;
 300         }
 301
 302         for (i = 0; i < nr_secs; i++) {
 303                 lba_list_media[i] = meta_list[i].lba;
 304                 meta_list[i].lba = lba_list_mem[i];
 305         }
 306
 307         /* Fill the holes in the original bio */
 308         i = 0;
 309         hole = find_first_zero_bit(read_bitmap, nr_secs);
 310         do {
 311                 int line_id = pblk_ppa_to_line(rqd->ppa_list[i]);
 312                 struct pblk_line *line = &pblk->lines[line_id];
 313
 314                 kref_put(&line->ref, pblk_line_put);
 315
 316                 meta_list[hole].lba = lba_list_media[i];
 317
 318                 src_bv = new_bio->bi_io_vec[i++];
 319                 dst_bv = orig_bio->bi_io_vec[bio_init_idx + hole];
 320
 321                 src_p = kmap_atomic(src_bv.bv_page);
 322                 dst_p = kmap_atomic(dst_bv.bv_page);
 323
 324                 memcpy(dst_p + dst_bv.bv_offset,
 325                         src_p + src_bv.bv_offset,
 326                         PBLK_EXPOSED_PAGE_SIZE);
 327
 328                 kunmap_atomic(src_p);
 329                 kunmap_atomic(dst_p);
 330
 331                 mempool_free(src_bv.bv_page, &pblk->page_bio_pool);
 332
 333                 hole = find_next_zero_bit(read_bitmap, nr_secs, hole + 1);
 334         } while (hole < nr_secs);
 335
 336         bio_put(new_bio);
 337
 338         /* restore original request */
 339         rqd->bio = NULL;
 340         rqd->nr_ppas = nr_secs;
 341
 342         __pblk_end_io_read(pblk, rqd, false);
 343         return NVM_IO_DONE;
 344
 345 fail:
 346         /* Free allocated pages in new bio */
 347         pblk_bio_free_pages(pblk, new_bio, 0, new_bio->bi_vcnt);
 348 fail_add_pages:
 349         pr_err("pblk: failed to perform partial read\n");
 350         __pblk_end_io_read(pblk, rqd, false);
 351         return NVM_IO_ERR;
 352 }
 353
 354 static void pblk_read_rq(struct pblk *pblk, struct nvm_rq *rqd, struct bio *bio,
 355                          sector_t lba, unsigned long *read_bitmap)
 356 {
 357         struct pblk_sec_meta *meta_list = rqd->meta_list;
 358         struct ppa_addr ppa;
 359
 360         pblk_lookup_l2p_seq(pblk, &ppa, lba, 1);
 361
 362 #ifdef CONFIG_NVM_DEBUG
 363         atomic_long_inc(&pblk->inflight_reads);
 364 #endif
 365
 366 retry:
 367         if (pblk_ppa_empty(ppa)) {
 368                 WARN_ON(test_and_set_bit(0, read_bitmap));
 369                 meta_list[0].lba = cpu_to_le64(ADDR_EMPTY);
 370                 return;
 371         }
 372
 373         /* Try to read from write buffer. The address is later checked on the
 374          * write buffer to prevent retrieving overwritten data.
 375          */
 376         if (pblk_addr_in_cache(ppa)) {
 377                 if (!pblk_read_from_cache(pblk, bio, lba, ppa, 0, 1)) {
 378                         pblk_lookup_l2p_seq(pblk, &ppa, lba, 1);
 379                         goto retry;
 380                 }
 381
 382                 WARN_ON(test_and_set_bit(0, read_bitmap));
 383                 meta_list[0].lba = cpu_to_le64(lba);
 384
 385 #ifdef CONFIG_NVM_DEBUG
 386                 atomic_long_inc(&pblk->cache_reads);
 387 #endif
 388         } else {
 389                 rqd->ppa_addr = ppa;
 390         }
 391
 392         rqd->flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
 393 }
 394
 395 int pblk_submit_read(struct pblk *pblk, struct bio *bio)
 396 {
 397         struct nvm_tgt_dev *dev = pblk->dev;
 398         struct request_queue *q = dev->q;
 399         sector_t blba = pblk_get_lba(bio);
 400         unsigned int nr_secs = pblk_get_secs(bio);
 401         struct pblk_g_ctx *r_ctx;
 402         struct nvm_rq *rqd;
 403         unsigned int bio_init_idx;
 404         unsigned long read_bitmap; /* Max 64 ppas per request */
 405         int ret = NVM_IO_ERR;
 406
 407         /* logic error: lba out-of-bounds. Ignore read request */
 408         if (blba >= pblk->rl.nr_secs || nr_secs > PBLK_MAX_REQ_ADDRS) {
 409                 WARN(1, "pblk: read lba out of bounds (lba:%llu, nr:%d)\n",
 410                                         (unsigned long long)blba, nr_secs);
 411                 return NVM_IO_ERR;
 412         }
 413
 414         generic_start_io_acct(q, READ, bio_sectors(bio), &pblk->disk->part0);
 415
 416         bitmap_zero(&read_bitmap, nr_secs);
 417
 418         rqd = pblk_alloc_rqd(pblk, PBLK_READ);
 419
 420         rqd->opcode = NVM_OP_PREAD;
 421         rqd->nr_ppas = nr_secs;
 422         rqd->bio = NULL; /* cloned bio if needed */
 423         rqd->private = pblk;
 424         rqd->end_io = pblk_end_io_read;
 425
 426         r_ctx = nvm_rq_to_pdu(rqd);
 427         r_ctx->start_time = jiffies;
 428         r_ctx->lba = blba;
 429         r_ctx->private = bio; /* original bio */
 430
 431         /* Save the index for this bio's start. This is needed in case
 432          * we need to fill a partial read.
 433          */
 434         bio_init_idx = pblk_get_bi_idx(bio);
 435
 436         rqd->meta_list = nvm_dev_dma_alloc(dev->parent, GFP_KERNEL,
 437                                                         &rqd->dma_meta_list);
 438         if (!rqd->meta_list) {
 439                 pr_err("pblk: not able to allocate ppa list\n");
 440                 goto fail_rqd_free;
 441         }
 442
 443         if (nr_secs > 1) {
 444                 rqd->ppa_list = rqd->meta_list + pblk_dma_meta_size;
 445                 rqd->dma_ppa_list = rqd->dma_meta_list + pblk_dma_meta_size;
 446
 447                 pblk_read_ppalist_rq(pblk, rqd, bio, blba, &read_bitmap);
 448         } else {
 449                 pblk_read_rq(pblk, rqd, bio, blba, &read_bitmap);
 450         }
 451
 452         if (bitmap_full(&read_bitmap, nr_secs)) {
 453                 atomic_inc(&pblk->inflight_io);
 454                 __pblk_end_io_read(pblk, rqd, false);
 455                 return NVM_IO_DONE;
 456         }
 457
 458         /* All sectors are to be read from the device */
 459         if (bitmap_empty(&read_bitmap, rqd->nr_ppas)) {
 460                 struct bio *int_bio = NULL;
 461
 462                 /* Clone read bio to deal with read errors internally */
 463                 int_bio = bio_clone_fast(bio, GFP_KERNEL, &pblk_bio_set);
 464                 if (!int_bio) {
 465                         pr_err("pblk: could not clone read bio\n");
 466                         goto fail_end_io;
 467                 }
 468
 469                 rqd->bio = int_bio;
 470
 471                 if (pblk_submit_io(pblk, rqd)) {
 472                         pr_err("pblk: read IO submission failed\n");
 473                         ret = NVM_IO_ERR;
 474                         goto fail_end_io;
 475                 }
 476
 477                 return NVM_IO_OK;
 478         }
 479
 480         /* The read bio request could be partially filled by the write buffer,
 481          * but there are some holes that need to be read from the drive.
 482          */
 483         return pblk_partial_read(pblk, rqd, bio, bio_init_idx, &read_bitmap);
 484
 485 fail_rqd_free:
 486         pblk_free_rqd(pblk, rqd, PBLK_READ);
 487         return ret;
 488 fail_end_io:
 489         __pblk_end_io_read(pblk, rqd, false);
 490         return ret;
 491 }
 492
 493 static int read_ppalist_rq_gc(struct pblk *pblk, struct nvm_rq *rqd,
 494                               struct pblk_line *line, u64 *lba_list,
 495                               u64 *paddr_list_gc, unsigned int nr_secs)
 496 {
 497         struct ppa_addr ppa_list_l2p[PBLK_MAX_REQ_ADDRS];
 498         struct ppa_addr ppa_gc;
 499         int valid_secs = 0;
 500         int i;
 501
 502         pblk_lookup_l2p_rand(pblk, ppa_list_l2p, lba_list, nr_secs);
 503
 504         for (i = 0; i < nr_secs; i++) {
 505                 if (lba_list[i] == ADDR_EMPTY)
 506                         continue;
 507
 508                 ppa_gc = addr_to_gen_ppa(pblk, paddr_list_gc[i], line->id);
 509                 if (!pblk_ppa_comp(ppa_list_l2p[i], ppa_gc)) {
 510                         paddr_list_gc[i] = lba_list[i] = ADDR_EMPTY;
 511                         continue;
 512                 }
 513
 514                 rqd->ppa_list[valid_secs++] = ppa_list_l2p[i];
 515         }
 516
 517 #ifdef CONFIG_NVM_DEBUG
 518         atomic_long_add(valid_secs, &pblk->inflight_reads);
 519 #endif
 520
 521         return valid_secs;
 522 }
 523
 524 static int read_rq_gc(struct pblk *pblk, struct nvm_rq *rqd,
 525                       struct pblk_line *line, sector_t lba,
 526                       u64 paddr_gc)
 527 {
 528         struct ppa_addr ppa_l2p, ppa_gc;
 529         int valid_secs = 0;
 530
 531         if (lba == ADDR_EMPTY)
 532                 goto out;
 533
 534         /* logic error: lba out-of-bounds */
 535         if (lba >= pblk->rl.nr_secs) {
 536                 WARN(1, "pblk: read lba out of bounds\n");
 537                 goto out;
 538         }
 539
 540         spin_lock(&pblk->trans_lock);
 541         ppa_l2p = pblk_trans_map_get(pblk, lba);
 542         spin_unlock(&pblk->trans_lock);
 543
 544         ppa_gc = addr_to_gen_ppa(pblk, paddr_gc, line->id);
 545         if (!pblk_ppa_comp(ppa_l2p, ppa_gc))
 546                 goto out;
 547
 548         rqd->ppa_addr = ppa_l2p;
 549         valid_secs = 1;
 550
 551 #ifdef CONFIG_NVM_DEBUG
 552         atomic_long_inc(&pblk->inflight_reads);
 553 #endif
 554
 555 out:
 556         return valid_secs;
 557 }
 558
 559 int pblk_submit_read_gc(struct pblk *pblk, struct pblk_gc_rq *gc_rq)
 560 {
 561         struct nvm_tgt_dev *dev = pblk->dev;
 562         struct nvm_geo *geo = &dev->geo;
 563         struct bio *bio;
 564         struct nvm_rq rqd;
 565         int data_len;
 566         int ret = NVM_IO_OK;
 567
 568         memset(&rqd, 0, sizeof(struct nvm_rq));
 569
 570         rqd.meta_list = nvm_dev_dma_alloc(dev->parent, GFP_KERNEL,
 571                                                         &rqd.dma_meta_list);
 572         if (!rqd.meta_list)
 573                 return -ENOMEM;
 574
 575         if (gc_rq->nr_secs > 1) {
 576                 rqd.ppa_list = rqd.meta_list + pblk_dma_meta_size;
 577                 rqd.dma_ppa_list = rqd.dma_meta_list + pblk_dma_meta_size;
 578
 579                 gc_rq->secs_to_gc = read_ppalist_rq_gc(pblk, &rqd, gc_rq->line,
 580                                                         gc_rq->lba_list,
 581                                                         gc_rq->paddr_list,
 582                                                         gc_rq->nr_secs);
 583                 if (gc_rq->secs_to_gc == 1)
 584                         rqd.ppa_addr = rqd.ppa_list[0];
 585         } else {
 586                 gc_rq->secs_to_gc = read_rq_gc(pblk, &rqd, gc_rq->line,
 587                                                         gc_rq->lba_list[0],
 588                                                         gc_rq->paddr_list[0]);
 589         }
 590
 591         if (!(gc_rq->secs_to_gc))
 592                 goto out;
 593
 594         data_len = (gc_rq->secs_to_gc) * geo->csecs;
 595         bio = pblk_bio_map_addr(pblk, gc_rq->data, gc_rq->secs_to_gc, data_len,
 596                                                 PBLK_VMALLOC_META, GFP_KERNEL);
 597         if (IS_ERR(bio)) {
 598                 pr_err("pblk: could not allocate GC bio (%lu)\n", PTR_ERR(bio));
 599                 goto err_free_dma;
 600         }
 601
 602         bio->bi_iter.bi_sector = 0; /* internal bio */
 603         bio_set_op_attrs(bio, REQ_OP_READ, 0);
 604
 605         rqd.opcode = NVM_OP_PREAD;
 606         rqd.nr_ppas = gc_rq->secs_to_gc;
 607         rqd.flags = pblk_set_read_mode(pblk, PBLK_READ_RANDOM);
 608         rqd.bio = bio;
 609
 610         if (pblk_submit_io_sync(pblk, &rqd)) {
 611                 ret = -EIO;
 612                 pr_err("pblk: GC read request failed\n");
 613                 goto err_free_bio;
 614         }
 615
 616         pblk_read_check_rand(pblk, &rqd, gc_rq->lba_list, gc_rq->nr_secs);
 617
 618         atomic_dec(&pblk->inflight_io);
 619
 620         if (rqd.error) {
 621                 atomic_long_inc(&pblk->read_failed_gc);
 622 #ifdef CONFIG_NVM_DEBUG
 623                 pblk_print_failed_rqd(pblk, &rqd, rqd.error);
 624 #endif
 625         }
 626
 627 #ifdef CONFIG_NVM_DEBUG
 628         atomic_long_add(gc_rq->secs_to_gc, &pblk->sync_reads);
 629         atomic_long_add(gc_rq->secs_to_gc, &pblk->recov_gc_reads);
 630         atomic_long_sub(gc_rq->secs_to_gc, &pblk->inflight_reads);
 631 #endif
 632
 633 out:
 634         nvm_dev_dma_free(dev->parent, rqd.meta_list, rqd.dma_meta_list);
 635         return ret;
 636
 637 err_free_bio:
 638         bio_put(bio);
 639 err_free_dma:
 640         nvm_dev_dma_free(dev->parent, rqd.meta_list, rqd.dma_meta_list);
 641         return ret;
 642 }