1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * NVMe ZNS-ZBD command implementation. 4 * Copyright (C) 2021 Western Digital Corporation or its affiliates. 5 */ 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 #include <linux/nvme.h> 8 #include <linux/blkdev.h> 9 #include "nvmet.h" 10 11 /* 12 * We set the Memory Page Size Minimum (MPSMIN) for target controller to 0 13 * which gets added by 12 in the nvme_enable_ctrl() which results in 2^12 = 4k 14 * as page_shift value. When calculating the ZASL use shift by 12. 15 */ 16 #define NVMET_MPSMIN_SHIFT 12 17 18 static inline u8 nvmet_zasl(unsigned int zone_append_sects) 19 { 20 /* 21 * Zone Append Size Limit (zasl) is expressed as a power of 2 value 22 * with the minimum memory page size (i.e. 12) as unit. 23 */ 24 return ilog2(zone_append_sects >> (NVMET_MPSMIN_SHIFT - 9)); 25 } 26 27 static int validate_conv_zones_cb(struct blk_zone *z, 28 unsigned int i, void *data) 29 { 30 if (z->type == BLK_ZONE_TYPE_CONVENTIONAL) 31 return -EOPNOTSUPP; 32 return 0; 33 } 34 35 bool nvmet_bdev_zns_enable(struct nvmet_ns *ns) 36 { 37 u8 zasl = nvmet_zasl(bdev_max_zone_append_sectors(ns->bdev)); 38 struct gendisk *bd_disk = ns->bdev->bd_disk; 39 int ret; 40 41 if (ns->subsys->zasl) { 42 if (ns->subsys->zasl > zasl) 43 return false; 44 } 45 ns->subsys->zasl = zasl; 46 47 /* 48 * Generic zoned block devices may have a smaller last zone which is 49 * not supported by ZNS. Exclude zoned drives that have such smaller 50 * last zone. 51 */ 52 if (get_capacity(bd_disk) & (bdev_zone_sectors(ns->bdev) - 1)) 53 return false; 54 /* 55 * ZNS does not define a conventional zone type. Use report zones 56 * to detect if the device has conventional zones and reject it if 57 * it does. 58 */ 59 ret = blkdev_report_zones(ns->bdev, 0, bdev_nr_zones(ns->bdev), 60 validate_conv_zones_cb, NULL); 61 if (ret < 0) 62 return false; 63 64 ns->blksize_shift = blksize_bits(bdev_logical_block_size(ns->bdev)); 65 66 return true; 67 } 68 69 void nvmet_execute_identify_ctrl_zns(struct nvmet_req *req) 70 { 71 u8 zasl = req->sq->ctrl->subsys->zasl; 72 struct nvme_id_ctrl_zns *id; 73 u16 status; 74 75 id = kzalloc_obj(*id); 76 if (!id) { 77 status = NVME_SC_INTERNAL; 78 goto out; 79 } 80 81 id->zasl = min_not_zero(nvmet_ctrl_mdts(req), zasl); 82 83 status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id)); 84 85 kfree(id); 86 out: 87 nvmet_req_complete(req, status); 88 } 89 90 void nvmet_execute_identify_ns_zns(struct nvmet_req *req) 91 { 92 struct nvme_id_ns_zns *id_zns = NULL; 93 u64 zsze; 94 u16 status; 95 u32 mar, mor; 96 97 if (le32_to_cpu(req->cmd->identify.nsid) == NVME_NSID_ALL) { 98 req->error_loc = offsetof(struct nvme_identify, nsid); 99 status = NVME_SC_INVALID_NS | NVME_STATUS_DNR; 100 goto out; 101 } 102 103 id_zns = kzalloc_obj(*id_zns); 104 if (!id_zns) { 105 status = NVME_SC_INTERNAL; 106 goto out; 107 } 108 109 status = nvmet_req_find_ns(req); 110 if (status) 111 goto done; 112 113 if (nvmet_ns_revalidate(req->ns)) { 114 mutex_lock(&req->ns->subsys->lock); 115 nvmet_ns_changed(req->ns->subsys, req->ns->nsid); 116 mutex_unlock(&req->ns->subsys->lock); 117 } 118 119 if (!req->ns->bdev || !bdev_is_zoned(req->ns->bdev)) { 120 status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR; 121 req->error_loc = offsetof(struct nvme_identify, nsid); 122 goto out; 123 } 124 125 zsze = (bdev_zone_sectors(req->ns->bdev) << 9) >> 126 req->ns->blksize_shift; 127 id_zns->lbafe[0].zsze = cpu_to_le64(zsze); 128 129 mor = bdev_max_open_zones(req->ns->bdev); 130 if (!mor) 131 mor = U32_MAX; 132 else 133 mor--; 134 id_zns->mor = cpu_to_le32(mor); 135 136 mar = bdev_max_active_zones(req->ns->bdev); 137 if (!mar) 138 mar = U32_MAX; 139 else 140 mar--; 141 id_zns->mar = cpu_to_le32(mar); 142 143 done: 144 status = nvmet_copy_to_sgl(req, 0, id_zns, sizeof(*id_zns)); 145 out: 146 kfree(id_zns); 147 nvmet_req_complete(req, status); 148 } 149 150 static u16 nvmet_bdev_validate_zone_mgmt_recv(struct nvmet_req *req) 151 { 152 sector_t sect = nvmet_lba_to_sect(req->ns, req->cmd->zmr.slba); 153 u32 out_bufsize = (le32_to_cpu(req->cmd->zmr.numd) + 1) << 2; 154 155 if (sect >= get_capacity(req->ns->bdev->bd_disk)) { 156 req->error_loc = offsetof(struct nvme_zone_mgmt_recv_cmd, slba); 157 return NVME_SC_LBA_RANGE | NVME_STATUS_DNR; 158 } 159 160 if (out_bufsize < sizeof(struct nvme_zone_report)) { 161 req->error_loc = offsetof(struct nvme_zone_mgmt_recv_cmd, numd); 162 return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR; 163 } 164 165 if (req->cmd->zmr.zra != NVME_ZRA_ZONE_REPORT) { 166 req->error_loc = offsetof(struct nvme_zone_mgmt_recv_cmd, zra); 167 return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR; 168 } 169 170 switch (req->cmd->zmr.pr) { 171 case 0: 172 case 1: 173 break; 174 default: 175 req->error_loc = offsetof(struct nvme_zone_mgmt_recv_cmd, pr); 176 return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR; 177 } 178 179 switch (req->cmd->zmr.zrasf) { 180 case NVME_ZRASF_ZONE_REPORT_ALL: 181 case NVME_ZRASF_ZONE_STATE_EMPTY: 182 case NVME_ZRASF_ZONE_STATE_IMP_OPEN: 183 case NVME_ZRASF_ZONE_STATE_EXP_OPEN: 184 case NVME_ZRASF_ZONE_STATE_CLOSED: 185 case NVME_ZRASF_ZONE_STATE_FULL: 186 case NVME_ZRASF_ZONE_STATE_READONLY: 187 case NVME_ZRASF_ZONE_STATE_OFFLINE: 188 break; 189 default: 190 req->error_loc = 191 offsetof(struct nvme_zone_mgmt_recv_cmd, zrasf); 192 return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR; 193 } 194 195 return NVME_SC_SUCCESS; 196 } 197 198 struct nvmet_report_zone_data { 199 struct nvmet_req *req; 200 u64 out_buf_offset; 201 u64 out_nr_zones; 202 u64 nr_zones; 203 u8 zrasf; 204 }; 205 206 static int nvmet_bdev_report_zone_cb(struct blk_zone *z, unsigned i, void *d) 207 { 208 static const unsigned int nvme_zrasf_to_blk_zcond[] = { 209 [NVME_ZRASF_ZONE_STATE_EMPTY] = BLK_ZONE_COND_EMPTY, 210 [NVME_ZRASF_ZONE_STATE_IMP_OPEN] = BLK_ZONE_COND_IMP_OPEN, 211 [NVME_ZRASF_ZONE_STATE_EXP_OPEN] = BLK_ZONE_COND_EXP_OPEN, 212 [NVME_ZRASF_ZONE_STATE_CLOSED] = BLK_ZONE_COND_CLOSED, 213 [NVME_ZRASF_ZONE_STATE_READONLY] = BLK_ZONE_COND_READONLY, 214 [NVME_ZRASF_ZONE_STATE_FULL] = BLK_ZONE_COND_FULL, 215 [NVME_ZRASF_ZONE_STATE_OFFLINE] = BLK_ZONE_COND_OFFLINE, 216 }; 217 struct nvmet_report_zone_data *rz = d; 218 219 if (rz->zrasf != NVME_ZRASF_ZONE_REPORT_ALL && 220 z->cond != nvme_zrasf_to_blk_zcond[rz->zrasf]) 221 return 0; 222 223 if (rz->nr_zones < rz->out_nr_zones) { 224 struct nvme_zone_descriptor zdesc = { }; 225 u16 status; 226 227 zdesc.zcap = nvmet_sect_to_lba(rz->req->ns, z->capacity); 228 zdesc.zslba = nvmet_sect_to_lba(rz->req->ns, z->start); 229 zdesc.wp = nvmet_sect_to_lba(rz->req->ns, z->wp); 230 zdesc.za = z->reset ? 1 << 2 : 0; 231 zdesc.zs = z->cond << 4; 232 zdesc.zt = z->type; 233 234 status = nvmet_copy_to_sgl(rz->req, rz->out_buf_offset, &zdesc, 235 sizeof(zdesc)); 236 if (status) 237 return -EINVAL; 238 239 rz->out_buf_offset += sizeof(zdesc); 240 } 241 242 rz->nr_zones++; 243 244 return 0; 245 } 246 247 static unsigned long nvmet_req_nr_zones_from_slba(struct nvmet_req *req) 248 { 249 unsigned int sect = nvmet_lba_to_sect(req->ns, req->cmd->zmr.slba); 250 251 return bdev_nr_zones(req->ns->bdev) - bdev_zone_no(req->ns->bdev, sect); 252 } 253 254 static unsigned long get_nr_zones_from_buf(struct nvmet_req *req, u32 bufsize) 255 { 256 if (bufsize <= sizeof(struct nvme_zone_report)) 257 return 0; 258 259 return (bufsize - sizeof(struct nvme_zone_report)) / 260 sizeof(struct nvme_zone_descriptor); 261 } 262 263 static void nvmet_bdev_zone_zmgmt_recv_work(struct work_struct *w) 264 { 265 struct nvmet_req *req = container_of(w, struct nvmet_req, z.zmgmt_work); 266 sector_t start_sect = nvmet_lba_to_sect(req->ns, req->cmd->zmr.slba); 267 unsigned long req_slba_nr_zones = nvmet_req_nr_zones_from_slba(req); 268 u32 out_bufsize = (le32_to_cpu(req->cmd->zmr.numd) + 1) << 2; 269 __le64 nr_zones; 270 u16 status; 271 int ret; 272 struct nvmet_report_zone_data rz_data = { 273 .out_nr_zones = get_nr_zones_from_buf(req, out_bufsize), 274 /* leave the place for report zone header */ 275 .out_buf_offset = sizeof(struct nvme_zone_report), 276 .zrasf = req->cmd->zmr.zrasf, 277 .nr_zones = 0, 278 .req = req, 279 }; 280 281 status = nvmet_bdev_validate_zone_mgmt_recv(req); 282 if (status) 283 goto out; 284 285 if (!req_slba_nr_zones) { 286 status = NVME_SC_SUCCESS; 287 goto out; 288 } 289 290 ret = blkdev_report_zones(req->ns->bdev, start_sect, req_slba_nr_zones, 291 nvmet_bdev_report_zone_cb, &rz_data); 292 if (ret < 0) { 293 status = NVME_SC_INTERNAL; 294 goto out; 295 } 296 297 /* 298 * Partial report (PR bit set): the host accepts an incomplete listing, 299 * so cap Number of Zones to the descriptors that fit in the buffer. 300 * Full report (PR bit clear): Number of Zones is the match count; fail 301 * if the buffer cannot hold every matching zone descriptor. 302 */ 303 if (req->cmd->zmr.pr) { 304 rz_data.nr_zones = min(rz_data.nr_zones, rz_data.out_nr_zones); 305 } else if (rz_data.nr_zones > rz_data.out_nr_zones) { 306 req->error_loc = offsetof(struct nvme_zone_mgmt_recv_cmd, numd); 307 status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR; 308 goto out; 309 } 310 311 nr_zones = cpu_to_le64(rz_data.nr_zones); 312 status = nvmet_copy_to_sgl(req, 0, &nr_zones, sizeof(nr_zones)); 313 314 out: 315 nvmet_req_complete(req, status); 316 } 317 318 void nvmet_bdev_execute_zone_mgmt_recv(struct nvmet_req *req) 319 { 320 INIT_WORK(&req->z.zmgmt_work, nvmet_bdev_zone_zmgmt_recv_work); 321 queue_work(zbd_wq, &req->z.zmgmt_work); 322 } 323 324 static inline enum req_op zsa_req_op(u8 zsa) 325 { 326 switch (zsa) { 327 case NVME_ZONE_OPEN: 328 return REQ_OP_ZONE_OPEN; 329 case NVME_ZONE_CLOSE: 330 return REQ_OP_ZONE_CLOSE; 331 case NVME_ZONE_FINISH: 332 return REQ_OP_ZONE_FINISH; 333 case NVME_ZONE_RESET: 334 return REQ_OP_ZONE_RESET; 335 default: 336 return REQ_OP_LAST; 337 } 338 } 339 340 static u16 blkdev_zone_mgmt_errno_to_nvme_status(int ret) 341 { 342 switch (ret) { 343 case 0: 344 return NVME_SC_SUCCESS; 345 case -EINVAL: 346 case -EIO: 347 return NVME_SC_ZONE_INVALID_TRANSITION | NVME_STATUS_DNR; 348 default: 349 return NVME_SC_INTERNAL; 350 } 351 } 352 353 struct nvmet_zone_mgmt_send_all_data { 354 unsigned long *zbitmap; 355 struct nvmet_req *req; 356 }; 357 358 static int zmgmt_send_scan_cb(struct blk_zone *z, unsigned i, void *d) 359 { 360 struct nvmet_zone_mgmt_send_all_data *data = d; 361 362 switch (zsa_req_op(data->req->cmd->zms.zsa)) { 363 case REQ_OP_ZONE_OPEN: 364 switch (z->cond) { 365 case BLK_ZONE_COND_CLOSED: 366 break; 367 default: 368 return 0; 369 } 370 break; 371 case REQ_OP_ZONE_CLOSE: 372 switch (z->cond) { 373 case BLK_ZONE_COND_IMP_OPEN: 374 case BLK_ZONE_COND_EXP_OPEN: 375 break; 376 default: 377 return 0; 378 } 379 break; 380 case REQ_OP_ZONE_FINISH: 381 switch (z->cond) { 382 case BLK_ZONE_COND_IMP_OPEN: 383 case BLK_ZONE_COND_EXP_OPEN: 384 case BLK_ZONE_COND_CLOSED: 385 break; 386 default: 387 return 0; 388 } 389 break; 390 default: 391 return -EINVAL; 392 } 393 394 set_bit(i, data->zbitmap); 395 396 return 0; 397 } 398 399 static u16 nvmet_bdev_zone_mgmt_emulate_all(struct nvmet_req *req) 400 { 401 struct block_device *bdev = req->ns->bdev; 402 unsigned int nr_zones = bdev_nr_zones(bdev); 403 struct bio *bio = NULL; 404 sector_t sector = 0; 405 int ret; 406 struct nvmet_zone_mgmt_send_all_data d = { 407 .req = req, 408 }; 409 410 d.zbitmap = kcalloc_node(BITS_TO_LONGS(nr_zones), sizeof(*(d.zbitmap)), 411 GFP_NOIO, bdev->bd_disk->node_id); 412 if (!d.zbitmap) { 413 ret = -ENOMEM; 414 goto out; 415 } 416 417 /* Scan and build bitmap of the eligible zones */ 418 ret = blkdev_report_zones(bdev, 0, nr_zones, zmgmt_send_scan_cb, &d); 419 if (ret != nr_zones) { 420 if (ret > 0) 421 ret = -EIO; 422 goto out; 423 } else { 424 /* We scanned all the zones */ 425 ret = 0; 426 } 427 428 while (sector < bdev_nr_sectors(bdev)) { 429 if (test_bit(disk_zone_no(bdev->bd_disk, sector), d.zbitmap)) { 430 bio = blk_next_bio(bio, bdev, 0, 431 zsa_req_op(req->cmd->zms.zsa) | REQ_SYNC, 432 GFP_KERNEL); 433 bio->bi_iter.bi_sector = sector; 434 /* This may take a while, so be nice to others */ 435 cond_resched(); 436 } 437 sector += bdev_zone_sectors(bdev); 438 } 439 440 if (bio) { 441 ret = submit_bio_wait(bio); 442 bio_put(bio); 443 } 444 445 out: 446 kfree(d.zbitmap); 447 448 return blkdev_zone_mgmt_errno_to_nvme_status(ret); 449 } 450 451 static u16 nvmet_bdev_execute_zmgmt_send_all(struct nvmet_req *req) 452 { 453 int ret; 454 455 switch (zsa_req_op(req->cmd->zms.zsa)) { 456 case REQ_OP_ZONE_RESET: 457 ret = blkdev_zone_mgmt(req->ns->bdev, REQ_OP_ZONE_RESET, 0, 458 get_capacity(req->ns->bdev->bd_disk)); 459 if (ret < 0) 460 return blkdev_zone_mgmt_errno_to_nvme_status(ret); 461 break; 462 case REQ_OP_ZONE_OPEN: 463 case REQ_OP_ZONE_CLOSE: 464 case REQ_OP_ZONE_FINISH: 465 return nvmet_bdev_zone_mgmt_emulate_all(req); 466 default: 467 /* this is needed to quiet compiler warning */ 468 req->error_loc = offsetof(struct nvme_zone_mgmt_send_cmd, zsa); 469 return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR; 470 } 471 472 return NVME_SC_SUCCESS; 473 } 474 475 static void nvmet_bdev_zmgmt_send_work(struct work_struct *w) 476 { 477 struct nvmet_req *req = container_of(w, struct nvmet_req, z.zmgmt_work); 478 sector_t sect = nvmet_lba_to_sect(req->ns, req->cmd->zms.slba); 479 enum req_op op = zsa_req_op(req->cmd->zms.zsa); 480 struct block_device *bdev = req->ns->bdev; 481 sector_t zone_sectors = bdev_zone_sectors(bdev); 482 u16 status = NVME_SC_SUCCESS; 483 int ret; 484 485 if (op == REQ_OP_LAST) { 486 req->error_loc = offsetof(struct nvme_zone_mgmt_send_cmd, zsa); 487 status = NVME_SC_ZONE_INVALID_TRANSITION | NVME_STATUS_DNR; 488 goto out; 489 } 490 491 /* when select all bit is set slba field is ignored */ 492 if (req->cmd->zms.select_all) { 493 status = nvmet_bdev_execute_zmgmt_send_all(req); 494 goto out; 495 } 496 497 if (sect >= get_capacity(bdev->bd_disk)) { 498 req->error_loc = offsetof(struct nvme_zone_mgmt_send_cmd, slba); 499 status = NVME_SC_LBA_RANGE | NVME_STATUS_DNR; 500 goto out; 501 } 502 503 if (sect & (zone_sectors - 1)) { 504 req->error_loc = offsetof(struct nvme_zone_mgmt_send_cmd, slba); 505 status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR; 506 goto out; 507 } 508 509 ret = blkdev_zone_mgmt(bdev, op, sect, zone_sectors); 510 if (ret < 0) 511 status = blkdev_zone_mgmt_errno_to_nvme_status(ret); 512 513 out: 514 nvmet_req_complete(req, status); 515 } 516 517 void nvmet_bdev_execute_zone_mgmt_send(struct nvmet_req *req) 518 { 519 INIT_WORK(&req->z.zmgmt_work, nvmet_bdev_zmgmt_send_work); 520 queue_work(zbd_wq, &req->z.zmgmt_work); 521 } 522 523 static void nvmet_bdev_zone_append_bio_done(struct bio *bio) 524 { 525 struct nvmet_req *req = bio->bi_private; 526 527 if (bio->bi_status == BLK_STS_OK) { 528 req->cqe->result.u64 = 529 nvmet_sect_to_lba(req->ns, bio->bi_iter.bi_sector); 530 } 531 532 nvmet_req_complete(req, blk_to_nvme_status(req, bio->bi_status)); 533 nvmet_req_bio_put(req, bio); 534 } 535 536 void nvmet_bdev_execute_zone_append(struct nvmet_req *req) 537 { 538 sector_t sect = nvmet_lba_to_sect(req->ns, req->cmd->rw.slba); 539 const blk_opf_t opf = REQ_OP_ZONE_APPEND | REQ_SYNC | REQ_IDLE; 540 u16 status = NVME_SC_SUCCESS; 541 unsigned int total_len = 0; 542 struct scatterlist *sg; 543 u32 data_len = nvmet_rw_data_len(req); 544 struct bio *bio; 545 int sg_cnt; 546 547 /* Request is completed on len mismatch in nvmet_check_transfer_len() */ 548 if (!nvmet_check_transfer_len(req, nvmet_rw_data_len(req))) 549 return; 550 551 if (data_len > 552 bdev_max_zone_append_sectors(req->ns->bdev) << SECTOR_SHIFT) { 553 req->error_loc = offsetof(struct nvme_rw_command, length); 554 status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR; 555 goto out; 556 } 557 558 if (!req->sg_cnt) { 559 nvmet_req_complete(req, 0); 560 return; 561 } 562 563 if (sect >= get_capacity(req->ns->bdev->bd_disk)) { 564 req->error_loc = offsetof(struct nvme_rw_command, slba); 565 status = NVME_SC_LBA_RANGE | NVME_STATUS_DNR; 566 goto out; 567 } 568 569 if (sect & (bdev_zone_sectors(req->ns->bdev) - 1)) { 570 req->error_loc = offsetof(struct nvme_rw_command, slba); 571 status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR; 572 goto out; 573 } 574 575 if (nvmet_use_inline_bvec(req)) { 576 bio = &req->z.inline_bio; 577 bio_init(bio, req->ns->bdev, req->inline_bvec, 578 ARRAY_SIZE(req->inline_bvec), opf); 579 } else { 580 bio = bio_alloc(req->ns->bdev, req->sg_cnt, opf, GFP_KERNEL); 581 } 582 583 bio->bi_end_io = nvmet_bdev_zone_append_bio_done; 584 bio->bi_iter.bi_sector = sect; 585 bio->bi_private = req; 586 if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA)) 587 bio->bi_opf |= REQ_FUA; 588 589 for_each_sg(req->sg, sg, req->sg_cnt, sg_cnt) { 590 unsigned int len = sg->length; 591 592 if (bio_add_page(bio, sg_page(sg), len, sg->offset) != len) { 593 status = NVME_SC_INTERNAL; 594 goto out_put_bio; 595 } 596 total_len += len; 597 } 598 599 if (total_len != data_len) { 600 status = NVME_SC_INTERNAL | NVME_STATUS_DNR; 601 goto out_put_bio; 602 } 603 604 submit_bio(bio); 605 return; 606 607 out_put_bio: 608 nvmet_req_bio_put(req, bio); 609 out: 610 nvmet_req_complete(req, status); 611 } 612 613 u16 nvmet_bdev_zns_parse_io_cmd(struct nvmet_req *req) 614 { 615 struct nvme_command *cmd = req->cmd; 616 617 switch (cmd->common.opcode) { 618 case nvme_cmd_zone_append: 619 req->execute = nvmet_bdev_execute_zone_append; 620 return 0; 621 case nvme_cmd_zone_mgmt_recv: 622 req->execute = nvmet_bdev_execute_zone_mgmt_recv; 623 return 0; 624 case nvme_cmd_zone_mgmt_send: 625 req->execute = nvmet_bdev_execute_zone_mgmt_send; 626 return 0; 627 default: 628 return nvmet_bdev_parse_io_cmd(req); 629 } 630 } 631