drivers/lightnvm/pblk-read.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2016 CNEX Labs
   4  * Initial release: Javier Gonzalez <javier@cnexlabs.com>
   5  *                  Matias Bjorling <matias@cnexlabs.com>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License version
   9  * 2 as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * pblk-read.c - pblk's read path
  17  */
  18
  19 #include "pblk.h"
  20
  21 /*
  22  * There is no guarantee that the value read from cache has not been updated and
  23  * resides at another location in the cache. We guarantee though that if the
  24  * value is read from the cache, it belongs to the mapped lba. In order to
  25  * guarantee and order between writes and reads are ordered, a flush must be
  26  * issued.
  27  */
  28 static int pblk_read_from_cache(struct pblk *pblk, struct bio *bio,
  29                                 sector_t lba, struct ppa_addr ppa,
  30                                 int bio_iter, bool advanced_bio)
  31 {
  32 #ifdef CONFIG_NVM_PBLK_DEBUG
  33         /* Callers must ensure that the ppa points to a cache address */
  34         BUG_ON(pblk_ppa_empty(ppa));
  35         BUG_ON(!pblk_addr_in_cache(ppa));
  36 #endif
  37
  38         return pblk_rb_copy_to_bio(&pblk->rwb, bio, lba, ppa,
  39                                                 bio_iter, advanced_bio);
  40 }
  41
  42 static void pblk_read_ppalist_rq(struct pblk *pblk, struct nvm_rq *rqd,
  43                                  struct bio *bio, sector_t blba,
  44                                  unsigned long *read_bitmap)
  45 {
  46         void *meta_list = rqd->meta_list;
  47         struct ppa_addr ppas[NVM_MAX_VLBA];
  48         int nr_secs = rqd->nr_ppas;
  49         bool advanced_bio = false;
  50         int i, j = 0;
  51
  52         pblk_lookup_l2p_seq(pblk, ppas, blba, nr_secs);
  53
  54         for (i = 0; i < nr_secs; i++) {
  55                 struct ppa_addr p = ppas[i];
  56                 struct pblk_sec_meta *meta = pblk_get_meta(pblk, meta_list, i);
  57                 sector_t lba = blba + i;
  58
  59 retry:
  60                 if (pblk_ppa_empty(p)) {
  61                         __le64 addr_empty = cpu_to_le64(ADDR_EMPTY);
  62
  63                         WARN_ON(test_and_set_bit(i, read_bitmap));
  64                         meta->lba = addr_empty;
  65
  66                         if (unlikely(!advanced_bio)) {
  67                                 bio_advance(bio, (i) * PBLK_EXPOSED_PAGE_SIZE);
  68                                 advanced_bio = true;
  69                         }
  70
  71                         goto next;
  72                 }
  73
  74                 /* Try to read from write buffer. The address is later checked
  75                  * on the write buffer to prevent retrieving overwritten data.
  76                  */
  77                 if (pblk_addr_in_cache(p)) {
  78                         if (!pblk_read_from_cache(pblk, bio, lba, p, i,
  79                                                                 advanced_bio)) {
  80                                 pblk_lookup_l2p_seq(pblk, &p, lba, 1);
  81                                 goto retry;
  82                         }
  83                         WARN_ON(test_and_set_bit(i, read_bitmap));
  84                         meta->lba = cpu_to_le64(lba);
  85                         advanced_bio = true;
  86 #ifdef CONFIG_NVM_PBLK_DEBUG
  87                         atomic_long_inc(&pblk->cache_reads);
  88 #endif
  89                 } else {
  90                         /* Read from media non-cached sectors */
  91                         rqd->ppa_list[j++] = p;
  92                 }
  93
  94 next:
  95                 if (advanced_bio)
  96                         bio_advance(bio, PBLK_EXPOSED_PAGE_SIZE);
  97         }
  98
  99         if (pblk_io_aligned(pblk, nr_secs))
 100                 rqd->is_seq = 1;
 101
 102 #ifdef CONFIG_NVM_PBLK_DEBUG
 103         atomic_long_add(nr_secs, &pblk->inflight_reads);
 104 #endif
 105 }
 106
 107
 108 static void pblk_read_check_seq(struct pblk *pblk, struct nvm_rq *rqd,
 109                                 sector_t blba)
 110 {
 111         void *meta_list = rqd->meta_list;
 112         int nr_lbas = rqd->nr_ppas;
 113         int i;
 114
 115         if (!pblk_is_oob_meta_supported(pblk))
 116                 return;
 117
 118         for (i = 0; i < nr_lbas; i++) {
 119                 struct pblk_sec_meta *meta = pblk_get_meta(pblk, meta_list, i);
 120                 u64 lba = le64_to_cpu(meta->lba);
 121
 122                 if (lba == ADDR_EMPTY)
 123                         continue;
 124
 125                 if (lba != blba + i) {
 126 #ifdef CONFIG_NVM_PBLK_DEBUG
 127                         struct ppa_addr *ppa_list = nvm_rq_to_ppa_list(rqd);
 128
 129                         print_ppa(pblk, &ppa_list[i], "seq", i);
 130 #endif
 131                         pblk_err(pblk, "corrupted read LBA (%llu/%llu)\n",
 132                                                         lba, (u64)blba + i);
 133                         WARN_ON(1);
 134                 }
 135         }
 136 }
 137
 138 /*
 139  * There can be holes in the lba list.
 140  */
 141 static void pblk_read_check_rand(struct pblk *pblk, struct nvm_rq *rqd,
 142                                  u64 *lba_list, int nr_lbas)
 143 {
 144         void *meta_lba_list = rqd->meta_list;
 145         int i, j;
 146
 147         if (!pblk_is_oob_meta_supported(pblk))
 148                 return;
 149
 150         for (i = 0, j = 0; i < nr_lbas; i++) {
 151                 struct pblk_sec_meta *meta = pblk_get_meta(pblk,
 152                                                            meta_lba_list, j);
 153                 u64 lba = lba_list[i];
 154                 u64 meta_lba;
 155
 156                 if (lba == ADDR_EMPTY)
 157                         continue;
 158
 159                 meta_lba = le64_to_cpu(meta->lba);
 160
 161                 if (lba != meta_lba) {
 162 #ifdef CONFIG_NVM_PBLK_DEBUG
 163                         struct ppa_addr *ppa_list = nvm_rq_to_ppa_list(rqd);
 164
 165                         print_ppa(pblk, &ppa_list[j], "rnd", j);
 166 #endif
 167                         pblk_err(pblk, "corrupted read LBA (%llu/%llu)\n",
 168                                                         meta_lba, lba);
 169                         WARN_ON(1);
 170                 }
 171
 172                 j++;
 173         }
 174
 175         WARN_ONCE(j != rqd->nr_ppas, "pblk: corrupted random request\n");
 176 }
 177
 178 static void pblk_end_user_read(struct bio *bio)
 179 {
 180 #ifdef CONFIG_NVM_PBLK_DEBUG
 181         WARN_ONCE(bio->bi_status, "pblk: corrupted read bio\n");
 182 #endif
 183         bio_endio(bio);
 184 }
 185
 186 static void __pblk_end_io_read(struct pblk *pblk, struct nvm_rq *rqd,
 187                                bool put_line)
 188 {
 189         struct nvm_tgt_dev *dev = pblk->dev;
 190         struct pblk_g_ctx *r_ctx = nvm_rq_to_pdu(rqd);
 191         struct bio *int_bio = rqd->bio;
 192         unsigned long start_time = r_ctx->start_time;
 193
 194         generic_end_io_acct(dev->q, REQ_OP_READ, &pblk->disk->part0, start_time);
 195
 196         if (rqd->error)
 197                 pblk_log_read_err(pblk, rqd);
 198
 199         pblk_read_check_seq(pblk, rqd, r_ctx->lba);
 200
 201         if (int_bio)
 202                 bio_put(int_bio);
 203
 204         if (put_line)
 205                 pblk_rq_to_line_put(pblk, rqd);
 206
 207 #ifdef CONFIG_NVM_PBLK_DEBUG
 208         atomic_long_add(rqd->nr_ppas, &pblk->sync_reads);
 209         atomic_long_sub(rqd->nr_ppas, &pblk->inflight_reads);
 210 #endif
 211
 212         pblk_free_rqd(pblk, rqd, PBLK_READ);
 213         atomic_dec(&pblk->inflight_io);
 214 }
 215
 216 static void pblk_end_io_read(struct nvm_rq *rqd)
 217 {
 218         struct pblk *pblk = rqd->private;
 219         struct pblk_g_ctx *r_ctx = nvm_rq_to_pdu(rqd);
 220         struct bio *bio = (struct bio *)r_ctx->private;
 221
 222         pblk_end_user_read(bio);
 223         __pblk_end_io_read(pblk, rqd, true);
 224 }
 225
 226 static void pblk_end_partial_read(struct nvm_rq *rqd)
 227 {
 228         struct pblk *pblk = rqd->private;
 229         struct pblk_g_ctx *r_ctx = nvm_rq_to_pdu(rqd);
 230         struct pblk_pr_ctx *pr_ctx = r_ctx->private;
 231         struct pblk_sec_meta *meta;
 232         struct bio *new_bio = rqd->bio;
 233         struct bio *bio = pr_ctx->orig_bio;
 234         struct bio_vec src_bv, dst_bv;
 235         void *meta_list = rqd->meta_list;
 236         int bio_init_idx = pr_ctx->bio_init_idx;
 237         unsigned long *read_bitmap = pr_ctx->bitmap;
 238         int nr_secs = pr_ctx->orig_nr_secs;
 239         int nr_holes = nr_secs - bitmap_weight(read_bitmap, nr_secs);
 240         void *src_p, *dst_p;
 241         int hole, i;
 242
 243         if (unlikely(nr_holes == 1)) {
 244                 struct ppa_addr ppa;
 245
 246                 ppa = rqd->ppa_addr;
 247                 rqd->ppa_list = pr_ctx->ppa_ptr;
 248                 rqd->dma_ppa_list = pr_ctx->dma_ppa_list;
 249                 rqd->ppa_list[0] = ppa;
 250         }
 251
 252         for (i = 0; i < nr_secs; i++) {
 253                 meta = pblk_get_meta(pblk, meta_list, i);
 254                 pr_ctx->lba_list_media[i] = le64_to_cpu(meta->lba);
 255                 meta->lba = cpu_to_le64(pr_ctx->lba_list_mem[i]);
 256         }
 257
 258         /* Fill the holes in the original bio */
 259         i = 0;
 260         hole = find_first_zero_bit(read_bitmap, nr_secs);
 261         do {
 262                 struct pblk_line *line;
 263
 264                 line = pblk_ppa_to_line(pblk, rqd->ppa_list[i]);
 265                 kref_put(&line->ref, pblk_line_put);
 266
 267                 meta = pblk_get_meta(pblk, meta_list, hole);
 268                 meta->lba = cpu_to_le64(pr_ctx->lba_list_media[i]);
 269
 270                 src_bv = new_bio->bi_io_vec[i++];
 271                 dst_bv = bio->bi_io_vec[bio_init_idx + hole];
 272
 273                 src_p = kmap_atomic(src_bv.bv_page);
 274                 dst_p = kmap_atomic(dst_bv.bv_page);
 275
 276                 memcpy(dst_p + dst_bv.bv_offset,
 277                         src_p + src_bv.bv_offset,
 278                         PBLK_EXPOSED_PAGE_SIZE);
 279
 280                 kunmap_atomic(src_p);
 281                 kunmap_atomic(dst_p);
 282
 283                 mempool_free(src_bv.bv_page, &pblk->page_bio_pool);
 284
 285                 hole = find_next_zero_bit(read_bitmap, nr_secs, hole + 1);
 286         } while (hole < nr_secs);
 287
 288         bio_put(new_bio);
 289         kfree(pr_ctx);
 290
 291         /* restore original request */
 292         rqd->bio = NULL;
 293         rqd->nr_ppas = nr_secs;
 294
 295         bio_endio(bio);
 296         __pblk_end_io_read(pblk, rqd, false);
 297 }
 298
 299 static int pblk_setup_partial_read(struct pblk *pblk, struct nvm_rq *rqd,
 300                             unsigned int bio_init_idx,
 301                             unsigned long *read_bitmap,
 302                             int nr_holes)
 303 {
 304         void *meta_list = rqd->meta_list;
 305         struct pblk_g_ctx *r_ctx = nvm_rq_to_pdu(rqd);
 306         struct pblk_pr_ctx *pr_ctx;
 307         struct bio *new_bio, *bio = r_ctx->private;
 308         int nr_secs = rqd->nr_ppas;
 309         int i;
 310
 311         new_bio = bio_alloc(GFP_KERNEL, nr_holes);
 312
 313         if (pblk_bio_add_pages(pblk, new_bio, GFP_KERNEL, nr_holes))
 314                 goto fail_bio_put;
 315
 316         if (nr_holes != new_bio->bi_vcnt) {
 317                 WARN_ONCE(1, "pblk: malformed bio\n");
 318                 goto fail_free_pages;
 319         }
 320
 321         pr_ctx = kzalloc(sizeof(struct pblk_pr_ctx), GFP_KERNEL);
 322         if (!pr_ctx)
 323                 goto fail_free_pages;
 324
 325         for (i = 0; i < nr_secs; i++) {
 326                 struct pblk_sec_meta *meta = pblk_get_meta(pblk, meta_list, i);
 327
 328                 pr_ctx->lba_list_mem[i] = le64_to_cpu(meta->lba);
 329         }
 330
 331         new_bio->bi_iter.bi_sector = 0; /* internal bio */
 332         bio_set_op_attrs(new_bio, REQ_OP_READ, 0);
 333
 334         rqd->bio = new_bio;
 335         rqd->nr_ppas = nr_holes;
 336
 337         pr_ctx->orig_bio = bio;
 338         bitmap_copy(pr_ctx->bitmap, read_bitmap, NVM_MAX_VLBA);
 339         pr_ctx->bio_init_idx = bio_init_idx;
 340         pr_ctx->orig_nr_secs = nr_secs;
 341         r_ctx->private = pr_ctx;
 342
 343         if (unlikely(nr_holes == 1)) {
 344                 pr_ctx->ppa_ptr = rqd->ppa_list;
 345                 pr_ctx->dma_ppa_list = rqd->dma_ppa_list;
 346                 rqd->ppa_addr = rqd->ppa_list[0];
 347         }
 348         return 0;
 349
 350 fail_free_pages:
 351         pblk_bio_free_pages(pblk, new_bio, 0, new_bio->bi_vcnt);
 352 fail_bio_put:
 353         bio_put(new_bio);
 354
 355         return -ENOMEM;
 356 }
 357
 358 static int pblk_partial_read_bio(struct pblk *pblk, struct nvm_rq *rqd,
 359                                  unsigned int bio_init_idx,
 360                                  unsigned long *read_bitmap, int nr_secs)
 361 {
 362         int nr_holes;
 363         int ret;
 364
 365         nr_holes = nr_secs - bitmap_weight(read_bitmap, nr_secs);
 366
 367         if (pblk_setup_partial_read(pblk, rqd, bio_init_idx, read_bitmap,
 368                                     nr_holes))
 369                 return NVM_IO_ERR;
 370
 371         rqd->end_io = pblk_end_partial_read;
 372
 373         ret = pblk_submit_io(pblk, rqd);
 374         if (ret) {
 375                 bio_put(rqd->bio);
 376                 pblk_err(pblk, "partial read IO submission failed\n");
 377                 goto err;
 378         }
 379
 380         return NVM_IO_OK;
 381
 382 err:
 383         pblk_err(pblk, "failed to perform partial read\n");
 384
 385         /* Free allocated pages in new bio */
 386         pblk_bio_free_pages(pblk, rqd->bio, 0, rqd->bio->bi_vcnt);
 387         __pblk_end_io_read(pblk, rqd, false);
 388         return NVM_IO_ERR;
 389 }
 390
 391 static void pblk_read_rq(struct pblk *pblk, struct nvm_rq *rqd, struct bio *bio,
 392                          sector_t lba, unsigned long *read_bitmap)
 393 {
 394         struct pblk_sec_meta *meta = pblk_get_meta(pblk, rqd->meta_list, 0);
 395         struct ppa_addr ppa;
 396
 397         pblk_lookup_l2p_seq(pblk, &ppa, lba, 1);
 398
 399 #ifdef CONFIG_NVM_PBLK_DEBUG
 400         atomic_long_inc(&pblk->inflight_reads);
 401 #endif
 402
 403 retry:
 404         if (pblk_ppa_empty(ppa)) {
 405                 __le64 addr_empty = cpu_to_le64(ADDR_EMPTY);
 406
 407                 WARN_ON(test_and_set_bit(0, read_bitmap));
 408                 meta->lba = addr_empty;
 409                 return;
 410         }
 411
 412         /* Try to read from write buffer. The address is later checked on the
 413          * write buffer to prevent retrieving overwritten data.
 414          */
 415         if (pblk_addr_in_cache(ppa)) {
 416                 if (!pblk_read_from_cache(pblk, bio, lba, ppa, 0, 1)) {
 417                         pblk_lookup_l2p_seq(pblk, &ppa, lba, 1);
 418                         goto retry;
 419                 }
 420
 421                 WARN_ON(test_and_set_bit(0, read_bitmap));
 422                 meta->lba = cpu_to_le64(lba);
 423
 424 #ifdef CONFIG_NVM_PBLK_DEBUG
 425                 atomic_long_inc(&pblk->cache_reads);
 426 #endif
 427         } else {
 428                 rqd->ppa_addr = ppa;
 429         }
 430 }
 431
 432 int pblk_submit_read(struct pblk *pblk, struct bio *bio)
 433 {
 434         struct nvm_tgt_dev *dev = pblk->dev;
 435         struct request_queue *q = dev->q;
 436         sector_t blba = pblk_get_lba(bio);
 437         unsigned int nr_secs = pblk_get_secs(bio);
 438         struct pblk_g_ctx *r_ctx;
 439         struct nvm_rq *rqd;
 440         unsigned int bio_init_idx;
 441         DECLARE_BITMAP(read_bitmap, NVM_MAX_VLBA);
 442         int ret = NVM_IO_ERR;
 443
 444         generic_start_io_acct(q, REQ_OP_READ, bio_sectors(bio),
 445                               &pblk->disk->part0);
 446
 447         bitmap_zero(read_bitmap, nr_secs);
 448
 449         rqd = pblk_alloc_rqd(pblk, PBLK_READ);
 450
 451         rqd->opcode = NVM_OP_PREAD;
 452         rqd->nr_ppas = nr_secs;
 453         rqd->bio = NULL; /* cloned bio if needed */
 454         rqd->private = pblk;
 455         rqd->end_io = pblk_end_io_read;
 456
 457         r_ctx = nvm_rq_to_pdu(rqd);
 458         r_ctx->start_time = jiffies;
 459         r_ctx->lba = blba;
 460         r_ctx->private = bio; /* original bio */
 461
 462         /* Save the index for this bio's start. This is needed in case
 463          * we need to fill a partial read.
 464          */
 465         bio_init_idx = pblk_get_bi_idx(bio);
 466
 467         if (pblk_alloc_rqd_meta(pblk, rqd))
 468                 goto fail_rqd_free;
 469
 470         if (nr_secs > 1)
 471                 pblk_read_ppalist_rq(pblk, rqd, bio, blba, read_bitmap);
 472         else
 473                 pblk_read_rq(pblk, rqd, bio, blba, read_bitmap);
 474
 475         if (bitmap_full(read_bitmap, nr_secs)) {
 476                 atomic_inc(&pblk->inflight_io);
 477                 __pblk_end_io_read(pblk, rqd, false);
 478                 return NVM_IO_DONE;
 479         }
 480
 481         /* All sectors are to be read from the device */
 482         if (bitmap_empty(read_bitmap, rqd->nr_ppas)) {
 483                 struct bio *int_bio = NULL;
 484
 485                 /* Clone read bio to deal with read errors internally */
 486                 int_bio = bio_clone_fast(bio, GFP_KERNEL, &pblk_bio_set);
 487                 if (!int_bio) {
 488                         pblk_err(pblk, "could not clone read bio\n");
 489                         goto fail_end_io;
 490                 }
 491
 492                 rqd->bio = int_bio;
 493
 494                 if (pblk_submit_io(pblk, rqd)) {
 495                         pblk_err(pblk, "read IO submission failed\n");
 496                         ret = NVM_IO_ERR;
 497                         goto fail_end_io;
 498                 }
 499
 500                 return NVM_IO_OK;
 501         }
 502
 503         /* The read bio request could be partially filled by the write buffer,
 504          * but there are some holes that need to be read from the drive.
 505          */
 506         ret = pblk_partial_read_bio(pblk, rqd, bio_init_idx, read_bitmap,
 507                                     nr_secs);
 508         if (ret)
 509                 goto fail_meta_free;
 510
 511         return NVM_IO_OK;
 512
 513 fail_meta_free:
 514         nvm_dev_dma_free(dev->parent, rqd->meta_list, rqd->dma_meta_list);
 515 fail_rqd_free:
 516         pblk_free_rqd(pblk, rqd, PBLK_READ);
 517         return ret;
 518 fail_end_io:
 519         __pblk_end_io_read(pblk, rqd, false);
 520         return ret;
 521 }
 522
 523 static int read_ppalist_rq_gc(struct pblk *pblk, struct nvm_rq *rqd,
 524                               struct pblk_line *line, u64 *lba_list,
 525                               u64 *paddr_list_gc, unsigned int nr_secs)
 526 {
 527         struct ppa_addr ppa_list_l2p[NVM_MAX_VLBA];
 528         struct ppa_addr ppa_gc;
 529         int valid_secs = 0;
 530         int i;
 531
 532         pblk_lookup_l2p_rand(pblk, ppa_list_l2p, lba_list, nr_secs);
 533
 534         for (i = 0; i < nr_secs; i++) {
 535                 if (lba_list[i] == ADDR_EMPTY)
 536                         continue;
 537
 538                 ppa_gc = addr_to_gen_ppa(pblk, paddr_list_gc[i], line->id);
 539                 if (!pblk_ppa_comp(ppa_list_l2p[i], ppa_gc)) {
 540                         paddr_list_gc[i] = lba_list[i] = ADDR_EMPTY;
 541                         continue;
 542                 }
 543
 544                 rqd->ppa_list[valid_secs++] = ppa_list_l2p[i];
 545         }
 546
 547 #ifdef CONFIG_NVM_PBLK_DEBUG
 548         atomic_long_add(valid_secs, &pblk->inflight_reads);
 549 #endif
 550
 551         return valid_secs;
 552 }
 553
 554 static int read_rq_gc(struct pblk *pblk, struct nvm_rq *rqd,
 555                       struct pblk_line *line, sector_t lba,
 556                       u64 paddr_gc)
 557 {
 558         struct ppa_addr ppa_l2p, ppa_gc;
 559         int valid_secs = 0;
 560
 561         if (lba == ADDR_EMPTY)
 562                 goto out;
 563
 564         /* logic error: lba out-of-bounds */
 565         if (lba >= pblk->rl.nr_secs) {
 566                 WARN(1, "pblk: read lba out of bounds\n");
 567                 goto out;
 568         }
 569
 570         spin_lock(&pblk->trans_lock);
 571         ppa_l2p = pblk_trans_map_get(pblk, lba);
 572         spin_unlock(&pblk->trans_lock);
 573
 574         ppa_gc = addr_to_gen_ppa(pblk, paddr_gc, line->id);
 575         if (!pblk_ppa_comp(ppa_l2p, ppa_gc))
 576                 goto out;
 577
 578         rqd->ppa_addr = ppa_l2p;
 579         valid_secs = 1;
 580
 581 #ifdef CONFIG_NVM_PBLK_DEBUG
 582         atomic_long_inc(&pblk->inflight_reads);
 583 #endif
 584
 585 out:
 586         return valid_secs;
 587 }
 588
 589 int pblk_submit_read_gc(struct pblk *pblk, struct pblk_gc_rq *gc_rq)
 590 {
 591         struct nvm_tgt_dev *dev = pblk->dev;
 592         struct nvm_geo *geo = &dev->geo;
 593         struct bio *bio;
 594         struct nvm_rq rqd;
 595         int data_len;
 596         int ret = NVM_IO_OK;
 597
 598         memset(&rqd, 0, sizeof(struct nvm_rq));
 599
 600         ret = pblk_alloc_rqd_meta(pblk, &rqd);
 601         if (ret)
 602                 return ret;
 603
 604         if (gc_rq->nr_secs > 1) {
 605                 gc_rq->secs_to_gc = read_ppalist_rq_gc(pblk, &rqd, gc_rq->line,
 606                                                         gc_rq->lba_list,
 607                                                         gc_rq->paddr_list,
 608                                                         gc_rq->nr_secs);
 609                 if (gc_rq->secs_to_gc == 1)
 610                         rqd.ppa_addr = rqd.ppa_list[0];
 611         } else {
 612                 gc_rq->secs_to_gc = read_rq_gc(pblk, &rqd, gc_rq->line,
 613                                                         gc_rq->lba_list[0],
 614                                                         gc_rq->paddr_list[0]);
 615         }
 616
 617         if (!(gc_rq->secs_to_gc))
 618                 goto out;
 619
 620         data_len = (gc_rq->secs_to_gc) * geo->csecs;
 621         bio = pblk_bio_map_addr(pblk, gc_rq->data, gc_rq->secs_to_gc, data_len,
 622                                                 PBLK_VMALLOC_META, GFP_KERNEL);
 623         if (IS_ERR(bio)) {
 624                 pblk_err(pblk, "could not allocate GC bio (%lu)\n",
 625                                                                 PTR_ERR(bio));
 626                 ret = PTR_ERR(bio);
 627                 goto err_free_dma;
 628         }
 629
 630         bio->bi_iter.bi_sector = 0; /* internal bio */
 631         bio_set_op_attrs(bio, REQ_OP_READ, 0);
 632
 633         rqd.opcode = NVM_OP_PREAD;
 634         rqd.nr_ppas = gc_rq->secs_to_gc;
 635         rqd.bio = bio;
 636
 637         if (pblk_submit_io_sync(pblk, &rqd)) {
 638                 ret = -EIO;
 639                 pblk_err(pblk, "GC read request failed\n");
 640                 goto err_free_bio;
 641         }
 642
 643         pblk_read_check_rand(pblk, &rqd, gc_rq->lba_list, gc_rq->nr_secs);
 644
 645         atomic_dec(&pblk->inflight_io);
 646
 647         if (rqd.error) {
 648                 atomic_long_inc(&pblk->read_failed_gc);
 649 #ifdef CONFIG_NVM_PBLK_DEBUG
 650                 pblk_print_failed_rqd(pblk, &rqd, rqd.error);
 651 #endif
 652         }
 653
 654 #ifdef CONFIG_NVM_PBLK_DEBUG
 655         atomic_long_add(gc_rq->secs_to_gc, &pblk->sync_reads);
 656         atomic_long_add(gc_rq->secs_to_gc, &pblk->recov_gc_reads);
 657         atomic_long_sub(gc_rq->secs_to_gc, &pblk->inflight_reads);
 658 #endif
 659
 660 out:
 661         pblk_free_rqd_meta(pblk, &rqd);
 662         return ret;
 663
 664 err_free_bio:
 665         bio_put(bio);
 666 err_free_dma:
 667         pblk_free_rqd_meta(pblk, &rqd);
 668         return ret;
 669 }