1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * NVMe over Fabrics TCP target. 4 * Copyright (c) 2018 Lightbits Labs. All rights reserved. 5 */ 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 #include <linux/module.h> 8 #include <linux/init.h> 9 #include <linux/slab.h> 10 #include <linux/err.h> 11 #include <linux/nvme-tcp.h> 12 #include <net/sock.h> 13 #include <net/tcp.h> 14 #include <linux/inet.h> 15 #include <linux/llist.h> 16 #include <crypto/hash.h> 17 #include <trace/events/sock.h> 18 19 #include "nvmet.h" 20 21 #define NVMET_TCP_DEF_INLINE_DATA_SIZE (4 * PAGE_SIZE) 22 23 static int param_store_val(const char *str, int *val, int min, int max) 24 { 25 int ret, new_val; 26 27 ret = kstrtoint(str, 10, &new_val); 28 if (ret) 29 return -EINVAL; 30 31 if (new_val < min || new_val > max) 32 return -EINVAL; 33 34 *val = new_val; 35 return 0; 36 } 37 38 static int set_params(const char *str, const struct kernel_param *kp) 39 { 40 return param_store_val(str, kp->arg, 0, INT_MAX); 41 } 42 43 static const struct kernel_param_ops set_param_ops = { 44 .set = set_params, 45 .get = param_get_int, 46 }; 47 48 /* Define the socket priority to use for connections were it is desirable 49 * that the NIC consider performing optimized packet processing or filtering. 50 * A non-zero value being sufficient to indicate general consideration of any 51 * possible optimization. Making it a module param allows for alternative 52 * values that may be unique for some NIC implementations. 53 */ 54 static int so_priority; 55 device_param_cb(so_priority, &set_param_ops, &so_priority, 0644); 56 MODULE_PARM_DESC(so_priority, "nvmet tcp socket optimize priority: Default 0"); 57 58 /* Define a time period (in usecs) that io_work() shall sample an activated 59 * queue before determining it to be idle. This optional module behavior 60 * can enable NIC solutions that support socket optimized packet processing 61 * using advanced interrupt moderation techniques. 62 */ 63 static int idle_poll_period_usecs; 64 device_param_cb(idle_poll_period_usecs, &set_param_ops, 65 &idle_poll_period_usecs, 0644); 66 MODULE_PARM_DESC(idle_poll_period_usecs, 67 "nvmet tcp io_work poll till idle time period in usecs: Default 0"); 68 69 #define NVMET_TCP_RECV_BUDGET 8 70 #define NVMET_TCP_SEND_BUDGET 8 71 #define NVMET_TCP_IO_WORK_BUDGET 64 72 73 enum nvmet_tcp_send_state { 74 NVMET_TCP_SEND_DATA_PDU, 75 NVMET_TCP_SEND_DATA, 76 NVMET_TCP_SEND_R2T, 77 NVMET_TCP_SEND_DDGST, 78 NVMET_TCP_SEND_RESPONSE 79 }; 80 81 enum nvmet_tcp_recv_state { 82 NVMET_TCP_RECV_PDU, 83 NVMET_TCP_RECV_DATA, 84 NVMET_TCP_RECV_DDGST, 85 NVMET_TCP_RECV_ERR, 86 }; 87 88 enum { 89 NVMET_TCP_F_INIT_FAILED = (1 << 0), 90 }; 91 92 struct nvmet_tcp_cmd { 93 struct nvmet_tcp_queue *queue; 94 struct nvmet_req req; 95 96 struct nvme_tcp_cmd_pdu *cmd_pdu; 97 struct nvme_tcp_rsp_pdu *rsp_pdu; 98 struct nvme_tcp_data_pdu *data_pdu; 99 struct nvme_tcp_r2t_pdu *r2t_pdu; 100 101 u32 rbytes_done; 102 u32 wbytes_done; 103 104 u32 pdu_len; 105 u32 pdu_recv; 106 int sg_idx; 107 struct msghdr recv_msg; 108 struct bio_vec *iov; 109 u32 flags; 110 111 struct list_head entry; 112 struct llist_node lentry; 113 114 /* send state */ 115 u32 offset; 116 struct scatterlist *cur_sg; 117 enum nvmet_tcp_send_state state; 118 119 __le32 exp_ddgst; 120 __le32 recv_ddgst; 121 }; 122 123 enum nvmet_tcp_queue_state { 124 NVMET_TCP_Q_CONNECTING, 125 NVMET_TCP_Q_LIVE, 126 NVMET_TCP_Q_DISCONNECTING, 127 }; 128 129 struct nvmet_tcp_queue { 130 struct socket *sock; 131 struct nvmet_tcp_port *port; 132 struct work_struct io_work; 133 struct nvmet_cq nvme_cq; 134 struct nvmet_sq nvme_sq; 135 136 /* send state */ 137 struct nvmet_tcp_cmd *cmds; 138 unsigned int nr_cmds; 139 struct list_head free_list; 140 struct llist_head resp_list; 141 struct list_head resp_send_list; 142 int send_list_len; 143 struct nvmet_tcp_cmd *snd_cmd; 144 145 /* recv state */ 146 int offset; 147 int left; 148 enum nvmet_tcp_recv_state rcv_state; 149 struct nvmet_tcp_cmd *cmd; 150 union nvme_tcp_pdu pdu; 151 152 /* digest state */ 153 bool hdr_digest; 154 bool data_digest; 155 struct ahash_request *snd_hash; 156 struct ahash_request *rcv_hash; 157 158 unsigned long poll_end; 159 160 spinlock_t state_lock; 161 enum nvmet_tcp_queue_state state; 162 163 struct sockaddr_storage sockaddr; 164 struct sockaddr_storage sockaddr_peer; 165 struct work_struct release_work; 166 167 int idx; 168 struct list_head queue_list; 169 170 struct nvmet_tcp_cmd connect; 171 172 struct page_frag_cache pf_cache; 173 174 void (*data_ready)(struct sock *); 175 void (*state_change)(struct sock *); 176 void (*write_space)(struct sock *); 177 }; 178 179 struct nvmet_tcp_port { 180 struct socket *sock; 181 struct work_struct accept_work; 182 struct nvmet_port *nport; 183 struct sockaddr_storage addr; 184 void (*data_ready)(struct sock *); 185 }; 186 187 static DEFINE_IDA(nvmet_tcp_queue_ida); 188 static LIST_HEAD(nvmet_tcp_queue_list); 189 static DEFINE_MUTEX(nvmet_tcp_queue_mutex); 190 191 static struct workqueue_struct *nvmet_tcp_wq; 192 static const struct nvmet_fabrics_ops nvmet_tcp_ops; 193 static void nvmet_tcp_free_cmd(struct nvmet_tcp_cmd *c); 194 static void nvmet_tcp_free_cmd_buffers(struct nvmet_tcp_cmd *cmd); 195 196 static inline u16 nvmet_tcp_cmd_tag(struct nvmet_tcp_queue *queue, 197 struct nvmet_tcp_cmd *cmd) 198 { 199 if (unlikely(!queue->nr_cmds)) { 200 /* We didn't allocate cmds yet, send 0xffff */ 201 return USHRT_MAX; 202 } 203 204 return cmd - queue->cmds; 205 } 206 207 static inline bool nvmet_tcp_has_data_in(struct nvmet_tcp_cmd *cmd) 208 { 209 return nvme_is_write(cmd->req.cmd) && 210 cmd->rbytes_done < cmd->req.transfer_len; 211 } 212 213 static inline bool nvmet_tcp_need_data_in(struct nvmet_tcp_cmd *cmd) 214 { 215 return nvmet_tcp_has_data_in(cmd) && !cmd->req.cqe->status; 216 } 217 218 static inline bool nvmet_tcp_need_data_out(struct nvmet_tcp_cmd *cmd) 219 { 220 return !nvme_is_write(cmd->req.cmd) && 221 cmd->req.transfer_len > 0 && 222 !cmd->req.cqe->status; 223 } 224 225 static inline bool nvmet_tcp_has_inline_data(struct nvmet_tcp_cmd *cmd) 226 { 227 return nvme_is_write(cmd->req.cmd) && cmd->pdu_len && 228 !cmd->rbytes_done; 229 } 230 231 static inline struct nvmet_tcp_cmd * 232 nvmet_tcp_get_cmd(struct nvmet_tcp_queue *queue) 233 { 234 struct nvmet_tcp_cmd *cmd; 235 236 cmd = list_first_entry_or_null(&queue->free_list, 237 struct nvmet_tcp_cmd, entry); 238 if (!cmd) 239 return NULL; 240 list_del_init(&cmd->entry); 241 242 cmd->rbytes_done = cmd->wbytes_done = 0; 243 cmd->pdu_len = 0; 244 cmd->pdu_recv = 0; 245 cmd->iov = NULL; 246 cmd->flags = 0; 247 return cmd; 248 } 249 250 static inline void nvmet_tcp_put_cmd(struct nvmet_tcp_cmd *cmd) 251 { 252 if (unlikely(cmd == &cmd->queue->connect)) 253 return; 254 255 list_add_tail(&cmd->entry, &cmd->queue->free_list); 256 } 257 258 static inline int queue_cpu(struct nvmet_tcp_queue *queue) 259 { 260 return queue->sock->sk->sk_incoming_cpu; 261 } 262 263 static inline u8 nvmet_tcp_hdgst_len(struct nvmet_tcp_queue *queue) 264 { 265 return queue->hdr_digest ? NVME_TCP_DIGEST_LENGTH : 0; 266 } 267 268 static inline u8 nvmet_tcp_ddgst_len(struct nvmet_tcp_queue *queue) 269 { 270 return queue->data_digest ? NVME_TCP_DIGEST_LENGTH : 0; 271 } 272 273 static inline void nvmet_tcp_hdgst(struct ahash_request *hash, 274 void *pdu, size_t len) 275 { 276 struct scatterlist sg; 277 278 sg_init_one(&sg, pdu, len); 279 ahash_request_set_crypt(hash, &sg, pdu + len, len); 280 crypto_ahash_digest(hash); 281 } 282 283 static int nvmet_tcp_verify_hdgst(struct nvmet_tcp_queue *queue, 284 void *pdu, size_t len) 285 { 286 struct nvme_tcp_hdr *hdr = pdu; 287 __le32 recv_digest; 288 __le32 exp_digest; 289 290 if (unlikely(!(hdr->flags & NVME_TCP_F_HDGST))) { 291 pr_err("queue %d: header digest enabled but no header digest\n", 292 queue->idx); 293 return -EPROTO; 294 } 295 296 recv_digest = *(__le32 *)(pdu + hdr->hlen); 297 nvmet_tcp_hdgst(queue->rcv_hash, pdu, len); 298 exp_digest = *(__le32 *)(pdu + hdr->hlen); 299 if (recv_digest != exp_digest) { 300 pr_err("queue %d: header digest error: recv %#x expected %#x\n", 301 queue->idx, le32_to_cpu(recv_digest), 302 le32_to_cpu(exp_digest)); 303 return -EPROTO; 304 } 305 306 return 0; 307 } 308 309 static int nvmet_tcp_check_ddgst(struct nvmet_tcp_queue *queue, void *pdu) 310 { 311 struct nvme_tcp_hdr *hdr = pdu; 312 u8 digest_len = nvmet_tcp_hdgst_len(queue); 313 u32 len; 314 315 len = le32_to_cpu(hdr->plen) - hdr->hlen - 316 (hdr->flags & NVME_TCP_F_HDGST ? digest_len : 0); 317 318 if (unlikely(len && !(hdr->flags & NVME_TCP_F_DDGST))) { 319 pr_err("queue %d: data digest flag is cleared\n", queue->idx); 320 return -EPROTO; 321 } 322 323 return 0; 324 } 325 326 static void nvmet_tcp_free_cmd_buffers(struct nvmet_tcp_cmd *cmd) 327 { 328 kfree(cmd->iov); 329 sgl_free(cmd->req.sg); 330 cmd->iov = NULL; 331 cmd->req.sg = NULL; 332 } 333 334 static void nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd) 335 { 336 struct bio_vec *iov = cmd->iov; 337 struct scatterlist *sg; 338 u32 length, offset, sg_offset; 339 int nr_pages; 340 341 length = cmd->pdu_len; 342 nr_pages = DIV_ROUND_UP(length, PAGE_SIZE); 343 offset = cmd->rbytes_done; 344 cmd->sg_idx = offset / PAGE_SIZE; 345 sg_offset = offset % PAGE_SIZE; 346 sg = &cmd->req.sg[cmd->sg_idx]; 347 348 while (length) { 349 u32 iov_len = min_t(u32, length, sg->length - sg_offset); 350 351 bvec_set_page(iov, sg_page(sg), sg->length, 352 sg->offset + sg_offset); 353 354 length -= iov_len; 355 sg = sg_next(sg); 356 iov++; 357 sg_offset = 0; 358 } 359 360 iov_iter_bvec(&cmd->recv_msg.msg_iter, ITER_DEST, cmd->iov, 361 nr_pages, cmd->pdu_len); 362 } 363 364 static void nvmet_tcp_fatal_error(struct nvmet_tcp_queue *queue) 365 { 366 queue->rcv_state = NVMET_TCP_RECV_ERR; 367 if (queue->nvme_sq.ctrl) 368 nvmet_ctrl_fatal_error(queue->nvme_sq.ctrl); 369 else 370 kernel_sock_shutdown(queue->sock, SHUT_RDWR); 371 } 372 373 static void nvmet_tcp_socket_error(struct nvmet_tcp_queue *queue, int status) 374 { 375 if (status == -EPIPE || status == -ECONNRESET) 376 kernel_sock_shutdown(queue->sock, SHUT_RDWR); 377 else 378 nvmet_tcp_fatal_error(queue); 379 } 380 381 static int nvmet_tcp_map_data(struct nvmet_tcp_cmd *cmd) 382 { 383 struct nvme_sgl_desc *sgl = &cmd->req.cmd->common.dptr.sgl; 384 u32 len = le32_to_cpu(sgl->length); 385 386 if (!len) 387 return 0; 388 389 if (sgl->type == ((NVME_SGL_FMT_DATA_DESC << 4) | 390 NVME_SGL_FMT_OFFSET)) { 391 if (!nvme_is_write(cmd->req.cmd)) 392 return NVME_SC_INVALID_FIELD | NVME_SC_DNR; 393 394 if (len > cmd->req.port->inline_data_size) 395 return NVME_SC_SGL_INVALID_OFFSET | NVME_SC_DNR; 396 cmd->pdu_len = len; 397 } 398 cmd->req.transfer_len += len; 399 400 cmd->req.sg = sgl_alloc(len, GFP_KERNEL, &cmd->req.sg_cnt); 401 if (!cmd->req.sg) 402 return NVME_SC_INTERNAL; 403 cmd->cur_sg = cmd->req.sg; 404 405 if (nvmet_tcp_has_data_in(cmd)) { 406 cmd->iov = kmalloc_array(cmd->req.sg_cnt, 407 sizeof(*cmd->iov), GFP_KERNEL); 408 if (!cmd->iov) 409 goto err; 410 } 411 412 return 0; 413 err: 414 nvmet_tcp_free_cmd_buffers(cmd); 415 return NVME_SC_INTERNAL; 416 } 417 418 static void nvmet_tcp_calc_ddgst(struct ahash_request *hash, 419 struct nvmet_tcp_cmd *cmd) 420 { 421 ahash_request_set_crypt(hash, cmd->req.sg, 422 (void *)&cmd->exp_ddgst, cmd->req.transfer_len); 423 crypto_ahash_digest(hash); 424 } 425 426 static void nvmet_setup_c2h_data_pdu(struct nvmet_tcp_cmd *cmd) 427 { 428 struct nvme_tcp_data_pdu *pdu = cmd->data_pdu; 429 struct nvmet_tcp_queue *queue = cmd->queue; 430 u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); 431 u8 ddgst = nvmet_tcp_ddgst_len(cmd->queue); 432 433 cmd->offset = 0; 434 cmd->state = NVMET_TCP_SEND_DATA_PDU; 435 436 pdu->hdr.type = nvme_tcp_c2h_data; 437 pdu->hdr.flags = NVME_TCP_F_DATA_LAST | (queue->nvme_sq.sqhd_disabled ? 438 NVME_TCP_F_DATA_SUCCESS : 0); 439 pdu->hdr.hlen = sizeof(*pdu); 440 pdu->hdr.pdo = pdu->hdr.hlen + hdgst; 441 pdu->hdr.plen = 442 cpu_to_le32(pdu->hdr.hlen + hdgst + 443 cmd->req.transfer_len + ddgst); 444 pdu->command_id = cmd->req.cqe->command_id; 445 pdu->data_length = cpu_to_le32(cmd->req.transfer_len); 446 pdu->data_offset = cpu_to_le32(cmd->wbytes_done); 447 448 if (queue->data_digest) { 449 pdu->hdr.flags |= NVME_TCP_F_DDGST; 450 nvmet_tcp_calc_ddgst(queue->snd_hash, cmd); 451 } 452 453 if (cmd->queue->hdr_digest) { 454 pdu->hdr.flags |= NVME_TCP_F_HDGST; 455 nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu)); 456 } 457 } 458 459 static void nvmet_setup_r2t_pdu(struct nvmet_tcp_cmd *cmd) 460 { 461 struct nvme_tcp_r2t_pdu *pdu = cmd->r2t_pdu; 462 struct nvmet_tcp_queue *queue = cmd->queue; 463 u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); 464 465 cmd->offset = 0; 466 cmd->state = NVMET_TCP_SEND_R2T; 467 468 pdu->hdr.type = nvme_tcp_r2t; 469 pdu->hdr.flags = 0; 470 pdu->hdr.hlen = sizeof(*pdu); 471 pdu->hdr.pdo = 0; 472 pdu->hdr.plen = cpu_to_le32(pdu->hdr.hlen + hdgst); 473 474 pdu->command_id = cmd->req.cmd->common.command_id; 475 pdu->ttag = nvmet_tcp_cmd_tag(cmd->queue, cmd); 476 pdu->r2t_length = cpu_to_le32(cmd->req.transfer_len - cmd->rbytes_done); 477 pdu->r2t_offset = cpu_to_le32(cmd->rbytes_done); 478 if (cmd->queue->hdr_digest) { 479 pdu->hdr.flags |= NVME_TCP_F_HDGST; 480 nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu)); 481 } 482 } 483 484 static void nvmet_setup_response_pdu(struct nvmet_tcp_cmd *cmd) 485 { 486 struct nvme_tcp_rsp_pdu *pdu = cmd->rsp_pdu; 487 struct nvmet_tcp_queue *queue = cmd->queue; 488 u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); 489 490 cmd->offset = 0; 491 cmd->state = NVMET_TCP_SEND_RESPONSE; 492 493 pdu->hdr.type = nvme_tcp_rsp; 494 pdu->hdr.flags = 0; 495 pdu->hdr.hlen = sizeof(*pdu); 496 pdu->hdr.pdo = 0; 497 pdu->hdr.plen = cpu_to_le32(pdu->hdr.hlen + hdgst); 498 if (cmd->queue->hdr_digest) { 499 pdu->hdr.flags |= NVME_TCP_F_HDGST; 500 nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu)); 501 } 502 } 503 504 static void nvmet_tcp_process_resp_list(struct nvmet_tcp_queue *queue) 505 { 506 struct llist_node *node; 507 struct nvmet_tcp_cmd *cmd; 508 509 for (node = llist_del_all(&queue->resp_list); node; node = node->next) { 510 cmd = llist_entry(node, struct nvmet_tcp_cmd, lentry); 511 list_add(&cmd->entry, &queue->resp_send_list); 512 queue->send_list_len++; 513 } 514 } 515 516 static struct nvmet_tcp_cmd *nvmet_tcp_fetch_cmd(struct nvmet_tcp_queue *queue) 517 { 518 queue->snd_cmd = list_first_entry_or_null(&queue->resp_send_list, 519 struct nvmet_tcp_cmd, entry); 520 if (!queue->snd_cmd) { 521 nvmet_tcp_process_resp_list(queue); 522 queue->snd_cmd = 523 list_first_entry_or_null(&queue->resp_send_list, 524 struct nvmet_tcp_cmd, entry); 525 if (unlikely(!queue->snd_cmd)) 526 return NULL; 527 } 528 529 list_del_init(&queue->snd_cmd->entry); 530 queue->send_list_len--; 531 532 if (nvmet_tcp_need_data_out(queue->snd_cmd)) 533 nvmet_setup_c2h_data_pdu(queue->snd_cmd); 534 else if (nvmet_tcp_need_data_in(queue->snd_cmd)) 535 nvmet_setup_r2t_pdu(queue->snd_cmd); 536 else 537 nvmet_setup_response_pdu(queue->snd_cmd); 538 539 return queue->snd_cmd; 540 } 541 542 static void nvmet_tcp_queue_response(struct nvmet_req *req) 543 { 544 struct nvmet_tcp_cmd *cmd = 545 container_of(req, struct nvmet_tcp_cmd, req); 546 struct nvmet_tcp_queue *queue = cmd->queue; 547 struct nvme_sgl_desc *sgl; 548 u32 len; 549 550 if (unlikely(cmd == queue->cmd)) { 551 sgl = &cmd->req.cmd->common.dptr.sgl; 552 len = le32_to_cpu(sgl->length); 553 554 /* 555 * Wait for inline data before processing the response. 556 * Avoid using helpers, this might happen before 557 * nvmet_req_init is completed. 558 */ 559 if (queue->rcv_state == NVMET_TCP_RECV_PDU && 560 len && len <= cmd->req.port->inline_data_size && 561 nvme_is_write(cmd->req.cmd)) 562 return; 563 } 564 565 llist_add(&cmd->lentry, &queue->resp_list); 566 queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &cmd->queue->io_work); 567 } 568 569 static void nvmet_tcp_execute_request(struct nvmet_tcp_cmd *cmd) 570 { 571 if (unlikely(cmd->flags & NVMET_TCP_F_INIT_FAILED)) 572 nvmet_tcp_queue_response(&cmd->req); 573 else 574 cmd->req.execute(&cmd->req); 575 } 576 577 static int nvmet_try_send_data_pdu(struct nvmet_tcp_cmd *cmd) 578 { 579 u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); 580 int left = sizeof(*cmd->data_pdu) - cmd->offset + hdgst; 581 int ret; 582 583 ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->data_pdu), 584 offset_in_page(cmd->data_pdu) + cmd->offset, 585 left, MSG_DONTWAIT | MSG_MORE | MSG_SENDPAGE_NOTLAST); 586 if (ret <= 0) 587 return ret; 588 589 cmd->offset += ret; 590 left -= ret; 591 592 if (left) 593 return -EAGAIN; 594 595 cmd->state = NVMET_TCP_SEND_DATA; 596 cmd->offset = 0; 597 return 1; 598 } 599 600 static int nvmet_try_send_data(struct nvmet_tcp_cmd *cmd, bool last_in_batch) 601 { 602 struct nvmet_tcp_queue *queue = cmd->queue; 603 int ret; 604 605 while (cmd->cur_sg) { 606 struct page *page = sg_page(cmd->cur_sg); 607 u32 left = cmd->cur_sg->length - cmd->offset; 608 int flags = MSG_DONTWAIT; 609 610 if ((!last_in_batch && cmd->queue->send_list_len) || 611 cmd->wbytes_done + left < cmd->req.transfer_len || 612 queue->data_digest || !queue->nvme_sq.sqhd_disabled) 613 flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST; 614 615 ret = kernel_sendpage(cmd->queue->sock, page, cmd->offset, 616 left, flags); 617 if (ret <= 0) 618 return ret; 619 620 cmd->offset += ret; 621 cmd->wbytes_done += ret; 622 623 /* Done with sg?*/ 624 if (cmd->offset == cmd->cur_sg->length) { 625 cmd->cur_sg = sg_next(cmd->cur_sg); 626 cmd->offset = 0; 627 } 628 } 629 630 if (queue->data_digest) { 631 cmd->state = NVMET_TCP_SEND_DDGST; 632 cmd->offset = 0; 633 } else { 634 if (queue->nvme_sq.sqhd_disabled) { 635 cmd->queue->snd_cmd = NULL; 636 nvmet_tcp_put_cmd(cmd); 637 } else { 638 nvmet_setup_response_pdu(cmd); 639 } 640 } 641 642 if (queue->nvme_sq.sqhd_disabled) 643 nvmet_tcp_free_cmd_buffers(cmd); 644 645 return 1; 646 647 } 648 649 static int nvmet_try_send_response(struct nvmet_tcp_cmd *cmd, 650 bool last_in_batch) 651 { 652 u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); 653 int left = sizeof(*cmd->rsp_pdu) - cmd->offset + hdgst; 654 int flags = MSG_DONTWAIT; 655 int ret; 656 657 if (!last_in_batch && cmd->queue->send_list_len) 658 flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST; 659 else 660 flags |= MSG_EOR; 661 662 ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->rsp_pdu), 663 offset_in_page(cmd->rsp_pdu) + cmd->offset, left, flags); 664 if (ret <= 0) 665 return ret; 666 cmd->offset += ret; 667 left -= ret; 668 669 if (left) 670 return -EAGAIN; 671 672 nvmet_tcp_free_cmd_buffers(cmd); 673 cmd->queue->snd_cmd = NULL; 674 nvmet_tcp_put_cmd(cmd); 675 return 1; 676 } 677 678 static int nvmet_try_send_r2t(struct nvmet_tcp_cmd *cmd, bool last_in_batch) 679 { 680 u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue); 681 int left = sizeof(*cmd->r2t_pdu) - cmd->offset + hdgst; 682 int flags = MSG_DONTWAIT; 683 int ret; 684 685 if (!last_in_batch && cmd->queue->send_list_len) 686 flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST; 687 else 688 flags |= MSG_EOR; 689 690 ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->r2t_pdu), 691 offset_in_page(cmd->r2t_pdu) + cmd->offset, left, flags); 692 if (ret <= 0) 693 return ret; 694 cmd->offset += ret; 695 left -= ret; 696 697 if (left) 698 return -EAGAIN; 699 700 cmd->queue->snd_cmd = NULL; 701 return 1; 702 } 703 704 static int nvmet_try_send_ddgst(struct nvmet_tcp_cmd *cmd, bool last_in_batch) 705 { 706 struct nvmet_tcp_queue *queue = cmd->queue; 707 int left = NVME_TCP_DIGEST_LENGTH - cmd->offset; 708 struct msghdr msg = { .msg_flags = MSG_DONTWAIT }; 709 struct kvec iov = { 710 .iov_base = (u8 *)&cmd->exp_ddgst + cmd->offset, 711 .iov_len = left 712 }; 713 int ret; 714 715 if (!last_in_batch && cmd->queue->send_list_len) 716 msg.msg_flags |= MSG_MORE; 717 else 718 msg.msg_flags |= MSG_EOR; 719 720 ret = kernel_sendmsg(queue->sock, &msg, &iov, 1, iov.iov_len); 721 if (unlikely(ret <= 0)) 722 return ret; 723 724 cmd->offset += ret; 725 left -= ret; 726 727 if (left) 728 return -EAGAIN; 729 730 if (queue->nvme_sq.sqhd_disabled) { 731 cmd->queue->snd_cmd = NULL; 732 nvmet_tcp_put_cmd(cmd); 733 } else { 734 nvmet_setup_response_pdu(cmd); 735 } 736 return 1; 737 } 738 739 static int nvmet_tcp_try_send_one(struct nvmet_tcp_queue *queue, 740 bool last_in_batch) 741 { 742 struct nvmet_tcp_cmd *cmd = queue->snd_cmd; 743 int ret = 0; 744 745 if (!cmd || queue->state == NVMET_TCP_Q_DISCONNECTING) { 746 cmd = nvmet_tcp_fetch_cmd(queue); 747 if (unlikely(!cmd)) 748 return 0; 749 } 750 751 if (cmd->state == NVMET_TCP_SEND_DATA_PDU) { 752 ret = nvmet_try_send_data_pdu(cmd); 753 if (ret <= 0) 754 goto done_send; 755 } 756 757 if (cmd->state == NVMET_TCP_SEND_DATA) { 758 ret = nvmet_try_send_data(cmd, last_in_batch); 759 if (ret <= 0) 760 goto done_send; 761 } 762 763 if (cmd->state == NVMET_TCP_SEND_DDGST) { 764 ret = nvmet_try_send_ddgst(cmd, last_in_batch); 765 if (ret <= 0) 766 goto done_send; 767 } 768 769 if (cmd->state == NVMET_TCP_SEND_R2T) { 770 ret = nvmet_try_send_r2t(cmd, last_in_batch); 771 if (ret <= 0) 772 goto done_send; 773 } 774 775 if (cmd->state == NVMET_TCP_SEND_RESPONSE) 776 ret = nvmet_try_send_response(cmd, last_in_batch); 777 778 done_send: 779 if (ret < 0) { 780 if (ret == -EAGAIN) 781 return 0; 782 return ret; 783 } 784 785 return 1; 786 } 787 788 static int nvmet_tcp_try_send(struct nvmet_tcp_queue *queue, 789 int budget, int *sends) 790 { 791 int i, ret = 0; 792 793 for (i = 0; i < budget; i++) { 794 ret = nvmet_tcp_try_send_one(queue, i == budget - 1); 795 if (unlikely(ret < 0)) { 796 nvmet_tcp_socket_error(queue, ret); 797 goto done; 798 } else if (ret == 0) { 799 break; 800 } 801 (*sends)++; 802 } 803 done: 804 return ret; 805 } 806 807 static void nvmet_prepare_receive_pdu(struct nvmet_tcp_queue *queue) 808 { 809 queue->offset = 0; 810 queue->left = sizeof(struct nvme_tcp_hdr); 811 queue->cmd = NULL; 812 queue->rcv_state = NVMET_TCP_RECV_PDU; 813 } 814 815 static void nvmet_tcp_free_crypto(struct nvmet_tcp_queue *queue) 816 { 817 struct crypto_ahash *tfm = crypto_ahash_reqtfm(queue->rcv_hash); 818 819 ahash_request_free(queue->rcv_hash); 820 ahash_request_free(queue->snd_hash); 821 crypto_free_ahash(tfm); 822 } 823 824 static int nvmet_tcp_alloc_crypto(struct nvmet_tcp_queue *queue) 825 { 826 struct crypto_ahash *tfm; 827 828 tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC); 829 if (IS_ERR(tfm)) 830 return PTR_ERR(tfm); 831 832 queue->snd_hash = ahash_request_alloc(tfm, GFP_KERNEL); 833 if (!queue->snd_hash) 834 goto free_tfm; 835 ahash_request_set_callback(queue->snd_hash, 0, NULL, NULL); 836 837 queue->rcv_hash = ahash_request_alloc(tfm, GFP_KERNEL); 838 if (!queue->rcv_hash) 839 goto free_snd_hash; 840 ahash_request_set_callback(queue->rcv_hash, 0, NULL, NULL); 841 842 return 0; 843 free_snd_hash: 844 ahash_request_free(queue->snd_hash); 845 free_tfm: 846 crypto_free_ahash(tfm); 847 return -ENOMEM; 848 } 849 850 851 static int nvmet_tcp_handle_icreq(struct nvmet_tcp_queue *queue) 852 { 853 struct nvme_tcp_icreq_pdu *icreq = &queue->pdu.icreq; 854 struct nvme_tcp_icresp_pdu *icresp = &queue->pdu.icresp; 855 struct msghdr msg = {}; 856 struct kvec iov; 857 int ret; 858 859 if (le32_to_cpu(icreq->hdr.plen) != sizeof(struct nvme_tcp_icreq_pdu)) { 860 pr_err("bad nvme-tcp pdu length (%d)\n", 861 le32_to_cpu(icreq->hdr.plen)); 862 nvmet_tcp_fatal_error(queue); 863 } 864 865 if (icreq->pfv != NVME_TCP_PFV_1_0) { 866 pr_err("queue %d: bad pfv %d\n", queue->idx, icreq->pfv); 867 return -EPROTO; 868 } 869 870 if (icreq->hpda != 0) { 871 pr_err("queue %d: unsupported hpda %d\n", queue->idx, 872 icreq->hpda); 873 return -EPROTO; 874 } 875 876 queue->hdr_digest = !!(icreq->digest & NVME_TCP_HDR_DIGEST_ENABLE); 877 queue->data_digest = !!(icreq->digest & NVME_TCP_DATA_DIGEST_ENABLE); 878 if (queue->hdr_digest || queue->data_digest) { 879 ret = nvmet_tcp_alloc_crypto(queue); 880 if (ret) 881 return ret; 882 } 883 884 memset(icresp, 0, sizeof(*icresp)); 885 icresp->hdr.type = nvme_tcp_icresp; 886 icresp->hdr.hlen = sizeof(*icresp); 887 icresp->hdr.pdo = 0; 888 icresp->hdr.plen = cpu_to_le32(icresp->hdr.hlen); 889 icresp->pfv = cpu_to_le16(NVME_TCP_PFV_1_0); 890 icresp->maxdata = cpu_to_le32(0x400000); /* 16M arbitrary limit */ 891 icresp->cpda = 0; 892 if (queue->hdr_digest) 893 icresp->digest |= NVME_TCP_HDR_DIGEST_ENABLE; 894 if (queue->data_digest) 895 icresp->digest |= NVME_TCP_DATA_DIGEST_ENABLE; 896 897 iov.iov_base = icresp; 898 iov.iov_len = sizeof(*icresp); 899 ret = kernel_sendmsg(queue->sock, &msg, &iov, 1, iov.iov_len); 900 if (ret < 0) 901 goto free_crypto; 902 903 queue->state = NVMET_TCP_Q_LIVE; 904 nvmet_prepare_receive_pdu(queue); 905 return 0; 906 free_crypto: 907 if (queue->hdr_digest || queue->data_digest) 908 nvmet_tcp_free_crypto(queue); 909 return ret; 910 } 911 912 static void nvmet_tcp_handle_req_failure(struct nvmet_tcp_queue *queue, 913 struct nvmet_tcp_cmd *cmd, struct nvmet_req *req) 914 { 915 size_t data_len = le32_to_cpu(req->cmd->common.dptr.sgl.length); 916 int ret; 917 918 /* 919 * This command has not been processed yet, hence we are trying to 920 * figure out if there is still pending data left to receive. If 921 * we don't, we can simply prepare for the next pdu and bail out, 922 * otherwise we will need to prepare a buffer and receive the 923 * stale data before continuing forward. 924 */ 925 if (!nvme_is_write(cmd->req.cmd) || !data_len || 926 data_len > cmd->req.port->inline_data_size) { 927 nvmet_prepare_receive_pdu(queue); 928 return; 929 } 930 931 ret = nvmet_tcp_map_data(cmd); 932 if (unlikely(ret)) { 933 pr_err("queue %d: failed to map data\n", queue->idx); 934 nvmet_tcp_fatal_error(queue); 935 return; 936 } 937 938 queue->rcv_state = NVMET_TCP_RECV_DATA; 939 nvmet_tcp_build_pdu_iovec(cmd); 940 cmd->flags |= NVMET_TCP_F_INIT_FAILED; 941 } 942 943 static int nvmet_tcp_handle_h2c_data_pdu(struct nvmet_tcp_queue *queue) 944 { 945 struct nvme_tcp_data_pdu *data = &queue->pdu.data; 946 struct nvmet_tcp_cmd *cmd; 947 948 if (likely(queue->nr_cmds)) { 949 if (unlikely(data->ttag >= queue->nr_cmds)) { 950 pr_err("queue %d: received out of bound ttag %u, nr_cmds %u\n", 951 queue->idx, data->ttag, queue->nr_cmds); 952 nvmet_tcp_fatal_error(queue); 953 return -EPROTO; 954 } 955 cmd = &queue->cmds[data->ttag]; 956 } else { 957 cmd = &queue->connect; 958 } 959 960 if (le32_to_cpu(data->data_offset) != cmd->rbytes_done) { 961 pr_err("ttag %u unexpected data offset %u (expected %u)\n", 962 data->ttag, le32_to_cpu(data->data_offset), 963 cmd->rbytes_done); 964 /* FIXME: use path and transport errors */ 965 nvmet_req_complete(&cmd->req, 966 NVME_SC_INVALID_FIELD | NVME_SC_DNR); 967 return -EPROTO; 968 } 969 970 cmd->pdu_len = le32_to_cpu(data->data_length); 971 cmd->pdu_recv = 0; 972 nvmet_tcp_build_pdu_iovec(cmd); 973 queue->cmd = cmd; 974 queue->rcv_state = NVMET_TCP_RECV_DATA; 975 976 return 0; 977 } 978 979 static int nvmet_tcp_done_recv_pdu(struct nvmet_tcp_queue *queue) 980 { 981 struct nvme_tcp_hdr *hdr = &queue->pdu.cmd.hdr; 982 struct nvme_command *nvme_cmd = &queue->pdu.cmd.cmd; 983 struct nvmet_req *req; 984 int ret; 985 986 if (unlikely(queue->state == NVMET_TCP_Q_CONNECTING)) { 987 if (hdr->type != nvme_tcp_icreq) { 988 pr_err("unexpected pdu type (%d) before icreq\n", 989 hdr->type); 990 nvmet_tcp_fatal_error(queue); 991 return -EPROTO; 992 } 993 return nvmet_tcp_handle_icreq(queue); 994 } 995 996 if (unlikely(hdr->type == nvme_tcp_icreq)) { 997 pr_err("queue %d: received icreq pdu in state %d\n", 998 queue->idx, queue->state); 999 nvmet_tcp_fatal_error(queue); 1000 return -EPROTO; 1001 } 1002 1003 if (hdr->type == nvme_tcp_h2c_data) { 1004 ret = nvmet_tcp_handle_h2c_data_pdu(queue); 1005 if (unlikely(ret)) 1006 return ret; 1007 return 0; 1008 } 1009 1010 queue->cmd = nvmet_tcp_get_cmd(queue); 1011 if (unlikely(!queue->cmd)) { 1012 /* This should never happen */ 1013 pr_err("queue %d: out of commands (%d) send_list_len: %d, opcode: %d", 1014 queue->idx, queue->nr_cmds, queue->send_list_len, 1015 nvme_cmd->common.opcode); 1016 nvmet_tcp_fatal_error(queue); 1017 return -ENOMEM; 1018 } 1019 1020 req = &queue->cmd->req; 1021 memcpy(req->cmd, nvme_cmd, sizeof(*nvme_cmd)); 1022 1023 if (unlikely(!nvmet_req_init(req, &queue->nvme_cq, 1024 &queue->nvme_sq, &nvmet_tcp_ops))) { 1025 pr_err("failed cmd %p id %d opcode %d, data_len: %d\n", 1026 req->cmd, req->cmd->common.command_id, 1027 req->cmd->common.opcode, 1028 le32_to_cpu(req->cmd->common.dptr.sgl.length)); 1029 1030 nvmet_tcp_handle_req_failure(queue, queue->cmd, req); 1031 return 0; 1032 } 1033 1034 ret = nvmet_tcp_map_data(queue->cmd); 1035 if (unlikely(ret)) { 1036 pr_err("queue %d: failed to map data\n", queue->idx); 1037 if (nvmet_tcp_has_inline_data(queue->cmd)) 1038 nvmet_tcp_fatal_error(queue); 1039 else 1040 nvmet_req_complete(req, ret); 1041 ret = -EAGAIN; 1042 goto out; 1043 } 1044 1045 if (nvmet_tcp_need_data_in(queue->cmd)) { 1046 if (nvmet_tcp_has_inline_data(queue->cmd)) { 1047 queue->rcv_state = NVMET_TCP_RECV_DATA; 1048 nvmet_tcp_build_pdu_iovec(queue->cmd); 1049 return 0; 1050 } 1051 /* send back R2T */ 1052 nvmet_tcp_queue_response(&queue->cmd->req); 1053 goto out; 1054 } 1055 1056 queue->cmd->req.execute(&queue->cmd->req); 1057 out: 1058 nvmet_prepare_receive_pdu(queue); 1059 return ret; 1060 } 1061 1062 static const u8 nvme_tcp_pdu_sizes[] = { 1063 [nvme_tcp_icreq] = sizeof(struct nvme_tcp_icreq_pdu), 1064 [nvme_tcp_cmd] = sizeof(struct nvme_tcp_cmd_pdu), 1065 [nvme_tcp_h2c_data] = sizeof(struct nvme_tcp_data_pdu), 1066 }; 1067 1068 static inline u8 nvmet_tcp_pdu_size(u8 type) 1069 { 1070 size_t idx = type; 1071 1072 return (idx < ARRAY_SIZE(nvme_tcp_pdu_sizes) && 1073 nvme_tcp_pdu_sizes[idx]) ? 1074 nvme_tcp_pdu_sizes[idx] : 0; 1075 } 1076 1077 static inline bool nvmet_tcp_pdu_valid(u8 type) 1078 { 1079 switch (type) { 1080 case nvme_tcp_icreq: 1081 case nvme_tcp_cmd: 1082 case nvme_tcp_h2c_data: 1083 /* fallthru */ 1084 return true; 1085 } 1086 1087 return false; 1088 } 1089 1090 static int nvmet_tcp_try_recv_pdu(struct nvmet_tcp_queue *queue) 1091 { 1092 struct nvme_tcp_hdr *hdr = &queue->pdu.cmd.hdr; 1093 int len; 1094 struct kvec iov; 1095 struct msghdr msg = { .msg_flags = MSG_DONTWAIT }; 1096 1097 recv: 1098 iov.iov_base = (void *)&queue->pdu + queue->offset; 1099 iov.iov_len = queue->left; 1100 len = kernel_recvmsg(queue->sock, &msg, &iov, 1, 1101 iov.iov_len, msg.msg_flags); 1102 if (unlikely(len < 0)) 1103 return len; 1104 1105 queue->offset += len; 1106 queue->left -= len; 1107 if (queue->left) 1108 return -EAGAIN; 1109 1110 if (queue->offset == sizeof(struct nvme_tcp_hdr)) { 1111 u8 hdgst = nvmet_tcp_hdgst_len(queue); 1112 1113 if (unlikely(!nvmet_tcp_pdu_valid(hdr->type))) { 1114 pr_err("unexpected pdu type %d\n", hdr->type); 1115 nvmet_tcp_fatal_error(queue); 1116 return -EIO; 1117 } 1118 1119 if (unlikely(hdr->hlen != nvmet_tcp_pdu_size(hdr->type))) { 1120 pr_err("pdu %d bad hlen %d\n", hdr->type, hdr->hlen); 1121 return -EIO; 1122 } 1123 1124 queue->left = hdr->hlen - queue->offset + hdgst; 1125 goto recv; 1126 } 1127 1128 if (queue->hdr_digest && 1129 nvmet_tcp_verify_hdgst(queue, &queue->pdu, hdr->hlen)) { 1130 nvmet_tcp_fatal_error(queue); /* fatal */ 1131 return -EPROTO; 1132 } 1133 1134 if (queue->data_digest && 1135 nvmet_tcp_check_ddgst(queue, &queue->pdu)) { 1136 nvmet_tcp_fatal_error(queue); /* fatal */ 1137 return -EPROTO; 1138 } 1139 1140 return nvmet_tcp_done_recv_pdu(queue); 1141 } 1142 1143 static void nvmet_tcp_prep_recv_ddgst(struct nvmet_tcp_cmd *cmd) 1144 { 1145 struct nvmet_tcp_queue *queue = cmd->queue; 1146 1147 nvmet_tcp_calc_ddgst(queue->rcv_hash, cmd); 1148 queue->offset = 0; 1149 queue->left = NVME_TCP_DIGEST_LENGTH; 1150 queue->rcv_state = NVMET_TCP_RECV_DDGST; 1151 } 1152 1153 static int nvmet_tcp_try_recv_data(struct nvmet_tcp_queue *queue) 1154 { 1155 struct nvmet_tcp_cmd *cmd = queue->cmd; 1156 int ret; 1157 1158 while (msg_data_left(&cmd->recv_msg)) { 1159 ret = sock_recvmsg(cmd->queue->sock, &cmd->recv_msg, 1160 cmd->recv_msg.msg_flags); 1161 if (ret <= 0) 1162 return ret; 1163 1164 cmd->pdu_recv += ret; 1165 cmd->rbytes_done += ret; 1166 } 1167 1168 if (queue->data_digest) { 1169 nvmet_tcp_prep_recv_ddgst(cmd); 1170 return 0; 1171 } 1172 1173 if (cmd->rbytes_done == cmd->req.transfer_len) 1174 nvmet_tcp_execute_request(cmd); 1175 1176 nvmet_prepare_receive_pdu(queue); 1177 return 0; 1178 } 1179 1180 static int nvmet_tcp_try_recv_ddgst(struct nvmet_tcp_queue *queue) 1181 { 1182 struct nvmet_tcp_cmd *cmd = queue->cmd; 1183 int ret; 1184 struct msghdr msg = { .msg_flags = MSG_DONTWAIT }; 1185 struct kvec iov = { 1186 .iov_base = (void *)&cmd->recv_ddgst + queue->offset, 1187 .iov_len = queue->left 1188 }; 1189 1190 ret = kernel_recvmsg(queue->sock, &msg, &iov, 1, 1191 iov.iov_len, msg.msg_flags); 1192 if (unlikely(ret < 0)) 1193 return ret; 1194 1195 queue->offset += ret; 1196 queue->left -= ret; 1197 if (queue->left) 1198 return -EAGAIN; 1199 1200 if (queue->data_digest && cmd->exp_ddgst != cmd->recv_ddgst) { 1201 pr_err("queue %d: cmd %d pdu (%d) data digest error: recv %#x expected %#x\n", 1202 queue->idx, cmd->req.cmd->common.command_id, 1203 queue->pdu.cmd.hdr.type, le32_to_cpu(cmd->recv_ddgst), 1204 le32_to_cpu(cmd->exp_ddgst)); 1205 nvmet_req_uninit(&cmd->req); 1206 nvmet_tcp_free_cmd_buffers(cmd); 1207 nvmet_tcp_fatal_error(queue); 1208 ret = -EPROTO; 1209 goto out; 1210 } 1211 1212 if (cmd->rbytes_done == cmd->req.transfer_len) 1213 nvmet_tcp_execute_request(cmd); 1214 1215 ret = 0; 1216 out: 1217 nvmet_prepare_receive_pdu(queue); 1218 return ret; 1219 } 1220 1221 static int nvmet_tcp_try_recv_one(struct nvmet_tcp_queue *queue) 1222 { 1223 int result = 0; 1224 1225 if (unlikely(queue->rcv_state == NVMET_TCP_RECV_ERR)) 1226 return 0; 1227 1228 if (queue->rcv_state == NVMET_TCP_RECV_PDU) { 1229 result = nvmet_tcp_try_recv_pdu(queue); 1230 if (result != 0) 1231 goto done_recv; 1232 } 1233 1234 if (queue->rcv_state == NVMET_TCP_RECV_DATA) { 1235 result = nvmet_tcp_try_recv_data(queue); 1236 if (result != 0) 1237 goto done_recv; 1238 } 1239 1240 if (queue->rcv_state == NVMET_TCP_RECV_DDGST) { 1241 result = nvmet_tcp_try_recv_ddgst(queue); 1242 if (result != 0) 1243 goto done_recv; 1244 } 1245 1246 done_recv: 1247 if (result < 0) { 1248 if (result == -EAGAIN) 1249 return 0; 1250 return result; 1251 } 1252 return 1; 1253 } 1254 1255 static int nvmet_tcp_try_recv(struct nvmet_tcp_queue *queue, 1256 int budget, int *recvs) 1257 { 1258 int i, ret = 0; 1259 1260 for (i = 0; i < budget; i++) { 1261 ret = nvmet_tcp_try_recv_one(queue); 1262 if (unlikely(ret < 0)) { 1263 nvmet_tcp_socket_error(queue, ret); 1264 goto done; 1265 } else if (ret == 0) { 1266 break; 1267 } 1268 (*recvs)++; 1269 } 1270 done: 1271 return ret; 1272 } 1273 1274 static void nvmet_tcp_schedule_release_queue(struct nvmet_tcp_queue *queue) 1275 { 1276 spin_lock(&queue->state_lock); 1277 if (queue->state != NVMET_TCP_Q_DISCONNECTING) { 1278 queue->state = NVMET_TCP_Q_DISCONNECTING; 1279 queue_work(nvmet_wq, &queue->release_work); 1280 } 1281 spin_unlock(&queue->state_lock); 1282 } 1283 1284 static inline void nvmet_tcp_arm_queue_deadline(struct nvmet_tcp_queue *queue) 1285 { 1286 queue->poll_end = jiffies + usecs_to_jiffies(idle_poll_period_usecs); 1287 } 1288 1289 static bool nvmet_tcp_check_queue_deadline(struct nvmet_tcp_queue *queue, 1290 int ops) 1291 { 1292 if (!idle_poll_period_usecs) 1293 return false; 1294 1295 if (ops) 1296 nvmet_tcp_arm_queue_deadline(queue); 1297 1298 return !time_after(jiffies, queue->poll_end); 1299 } 1300 1301 static void nvmet_tcp_io_work(struct work_struct *w) 1302 { 1303 struct nvmet_tcp_queue *queue = 1304 container_of(w, struct nvmet_tcp_queue, io_work); 1305 bool pending; 1306 int ret, ops = 0; 1307 1308 do { 1309 pending = false; 1310 1311 ret = nvmet_tcp_try_recv(queue, NVMET_TCP_RECV_BUDGET, &ops); 1312 if (ret > 0) 1313 pending = true; 1314 else if (ret < 0) 1315 return; 1316 1317 ret = nvmet_tcp_try_send(queue, NVMET_TCP_SEND_BUDGET, &ops); 1318 if (ret > 0) 1319 pending = true; 1320 else if (ret < 0) 1321 return; 1322 1323 } while (pending && ops < NVMET_TCP_IO_WORK_BUDGET); 1324 1325 /* 1326 * Requeue the worker if idle deadline period is in progress or any 1327 * ops activity was recorded during the do-while loop above. 1328 */ 1329 if (nvmet_tcp_check_queue_deadline(queue, ops) || pending) 1330 queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work); 1331 } 1332 1333 static int nvmet_tcp_alloc_cmd(struct nvmet_tcp_queue *queue, 1334 struct nvmet_tcp_cmd *c) 1335 { 1336 u8 hdgst = nvmet_tcp_hdgst_len(queue); 1337 1338 c->queue = queue; 1339 c->req.port = queue->port->nport; 1340 1341 c->cmd_pdu = page_frag_alloc(&queue->pf_cache, 1342 sizeof(*c->cmd_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO); 1343 if (!c->cmd_pdu) 1344 return -ENOMEM; 1345 c->req.cmd = &c->cmd_pdu->cmd; 1346 1347 c->rsp_pdu = page_frag_alloc(&queue->pf_cache, 1348 sizeof(*c->rsp_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO); 1349 if (!c->rsp_pdu) 1350 goto out_free_cmd; 1351 c->req.cqe = &c->rsp_pdu->cqe; 1352 1353 c->data_pdu = page_frag_alloc(&queue->pf_cache, 1354 sizeof(*c->data_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO); 1355 if (!c->data_pdu) 1356 goto out_free_rsp; 1357 1358 c->r2t_pdu = page_frag_alloc(&queue->pf_cache, 1359 sizeof(*c->r2t_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO); 1360 if (!c->r2t_pdu) 1361 goto out_free_data; 1362 1363 c->recv_msg.msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL; 1364 1365 list_add_tail(&c->entry, &queue->free_list); 1366 1367 return 0; 1368 out_free_data: 1369 page_frag_free(c->data_pdu); 1370 out_free_rsp: 1371 page_frag_free(c->rsp_pdu); 1372 out_free_cmd: 1373 page_frag_free(c->cmd_pdu); 1374 return -ENOMEM; 1375 } 1376 1377 static void nvmet_tcp_free_cmd(struct nvmet_tcp_cmd *c) 1378 { 1379 page_frag_free(c->r2t_pdu); 1380 page_frag_free(c->data_pdu); 1381 page_frag_free(c->rsp_pdu); 1382 page_frag_free(c->cmd_pdu); 1383 } 1384 1385 static int nvmet_tcp_alloc_cmds(struct nvmet_tcp_queue *queue) 1386 { 1387 struct nvmet_tcp_cmd *cmds; 1388 int i, ret = -EINVAL, nr_cmds = queue->nr_cmds; 1389 1390 cmds = kcalloc(nr_cmds, sizeof(struct nvmet_tcp_cmd), GFP_KERNEL); 1391 if (!cmds) 1392 goto out; 1393 1394 for (i = 0; i < nr_cmds; i++) { 1395 ret = nvmet_tcp_alloc_cmd(queue, cmds + i); 1396 if (ret) 1397 goto out_free; 1398 } 1399 1400 queue->cmds = cmds; 1401 1402 return 0; 1403 out_free: 1404 while (--i >= 0) 1405 nvmet_tcp_free_cmd(cmds + i); 1406 kfree(cmds); 1407 out: 1408 return ret; 1409 } 1410 1411 static void nvmet_tcp_free_cmds(struct nvmet_tcp_queue *queue) 1412 { 1413 struct nvmet_tcp_cmd *cmds = queue->cmds; 1414 int i; 1415 1416 for (i = 0; i < queue->nr_cmds; i++) 1417 nvmet_tcp_free_cmd(cmds + i); 1418 1419 nvmet_tcp_free_cmd(&queue->connect); 1420 kfree(cmds); 1421 } 1422 1423 static void nvmet_tcp_restore_socket_callbacks(struct nvmet_tcp_queue *queue) 1424 { 1425 struct socket *sock = queue->sock; 1426 1427 write_lock_bh(&sock->sk->sk_callback_lock); 1428 sock->sk->sk_data_ready = queue->data_ready; 1429 sock->sk->sk_state_change = queue->state_change; 1430 sock->sk->sk_write_space = queue->write_space; 1431 sock->sk->sk_user_data = NULL; 1432 write_unlock_bh(&sock->sk->sk_callback_lock); 1433 } 1434 1435 static void nvmet_tcp_uninit_data_in_cmds(struct nvmet_tcp_queue *queue) 1436 { 1437 struct nvmet_tcp_cmd *cmd = queue->cmds; 1438 int i; 1439 1440 for (i = 0; i < queue->nr_cmds; i++, cmd++) { 1441 if (nvmet_tcp_need_data_in(cmd)) 1442 nvmet_req_uninit(&cmd->req); 1443 } 1444 1445 if (!queue->nr_cmds && nvmet_tcp_need_data_in(&queue->connect)) { 1446 /* failed in connect */ 1447 nvmet_req_uninit(&queue->connect.req); 1448 } 1449 } 1450 1451 static void nvmet_tcp_free_cmd_data_in_buffers(struct nvmet_tcp_queue *queue) 1452 { 1453 struct nvmet_tcp_cmd *cmd = queue->cmds; 1454 int i; 1455 1456 for (i = 0; i < queue->nr_cmds; i++, cmd++) { 1457 if (nvmet_tcp_need_data_in(cmd)) 1458 nvmet_tcp_free_cmd_buffers(cmd); 1459 } 1460 1461 if (!queue->nr_cmds && nvmet_tcp_need_data_in(&queue->connect)) 1462 nvmet_tcp_free_cmd_buffers(&queue->connect); 1463 } 1464 1465 static void nvmet_tcp_release_queue_work(struct work_struct *w) 1466 { 1467 struct page *page; 1468 struct nvmet_tcp_queue *queue = 1469 container_of(w, struct nvmet_tcp_queue, release_work); 1470 1471 mutex_lock(&nvmet_tcp_queue_mutex); 1472 list_del_init(&queue->queue_list); 1473 mutex_unlock(&nvmet_tcp_queue_mutex); 1474 1475 nvmet_tcp_restore_socket_callbacks(queue); 1476 cancel_work_sync(&queue->io_work); 1477 /* stop accepting incoming data */ 1478 queue->rcv_state = NVMET_TCP_RECV_ERR; 1479 1480 nvmet_tcp_uninit_data_in_cmds(queue); 1481 nvmet_sq_destroy(&queue->nvme_sq); 1482 cancel_work_sync(&queue->io_work); 1483 nvmet_tcp_free_cmd_data_in_buffers(queue); 1484 sock_release(queue->sock); 1485 nvmet_tcp_free_cmds(queue); 1486 if (queue->hdr_digest || queue->data_digest) 1487 nvmet_tcp_free_crypto(queue); 1488 ida_free(&nvmet_tcp_queue_ida, queue->idx); 1489 1490 page = virt_to_head_page(queue->pf_cache.va); 1491 __page_frag_cache_drain(page, queue->pf_cache.pagecnt_bias); 1492 kfree(queue); 1493 } 1494 1495 static void nvmet_tcp_data_ready(struct sock *sk) 1496 { 1497 struct nvmet_tcp_queue *queue; 1498 1499 trace_sk_data_ready(sk); 1500 1501 read_lock_bh(&sk->sk_callback_lock); 1502 queue = sk->sk_user_data; 1503 if (likely(queue)) 1504 queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work); 1505 read_unlock_bh(&sk->sk_callback_lock); 1506 } 1507 1508 static void nvmet_tcp_write_space(struct sock *sk) 1509 { 1510 struct nvmet_tcp_queue *queue; 1511 1512 read_lock_bh(&sk->sk_callback_lock); 1513 queue = sk->sk_user_data; 1514 if (unlikely(!queue)) 1515 goto out; 1516 1517 if (unlikely(queue->state == NVMET_TCP_Q_CONNECTING)) { 1518 queue->write_space(sk); 1519 goto out; 1520 } 1521 1522 if (sk_stream_is_writeable(sk)) { 1523 clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1524 queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work); 1525 } 1526 out: 1527 read_unlock_bh(&sk->sk_callback_lock); 1528 } 1529 1530 static void nvmet_tcp_state_change(struct sock *sk) 1531 { 1532 struct nvmet_tcp_queue *queue; 1533 1534 read_lock_bh(&sk->sk_callback_lock); 1535 queue = sk->sk_user_data; 1536 if (!queue) 1537 goto done; 1538 1539 switch (sk->sk_state) { 1540 case TCP_FIN_WAIT2: 1541 case TCP_LAST_ACK: 1542 break; 1543 case TCP_FIN_WAIT1: 1544 case TCP_CLOSE_WAIT: 1545 case TCP_CLOSE: 1546 /* FALLTHRU */ 1547 nvmet_tcp_schedule_release_queue(queue); 1548 break; 1549 default: 1550 pr_warn("queue %d unhandled state %d\n", 1551 queue->idx, sk->sk_state); 1552 } 1553 done: 1554 read_unlock_bh(&sk->sk_callback_lock); 1555 } 1556 1557 static int nvmet_tcp_set_queue_sock(struct nvmet_tcp_queue *queue) 1558 { 1559 struct socket *sock = queue->sock; 1560 struct inet_sock *inet = inet_sk(sock->sk); 1561 int ret; 1562 1563 ret = kernel_getsockname(sock, 1564 (struct sockaddr *)&queue->sockaddr); 1565 if (ret < 0) 1566 return ret; 1567 1568 ret = kernel_getpeername(sock, 1569 (struct sockaddr *)&queue->sockaddr_peer); 1570 if (ret < 0) 1571 return ret; 1572 1573 /* 1574 * Cleanup whatever is sitting in the TCP transmit queue on socket 1575 * close. This is done to prevent stale data from being sent should 1576 * the network connection be restored before TCP times out. 1577 */ 1578 sock_no_linger(sock->sk); 1579 1580 if (so_priority > 0) 1581 sock_set_priority(sock->sk, so_priority); 1582 1583 /* Set socket type of service */ 1584 if (inet->rcv_tos > 0) 1585 ip_sock_set_tos(sock->sk, inet->rcv_tos); 1586 1587 ret = 0; 1588 write_lock_bh(&sock->sk->sk_callback_lock); 1589 if (sock->sk->sk_state != TCP_ESTABLISHED) { 1590 /* 1591 * If the socket is already closing, don't even start 1592 * consuming it 1593 */ 1594 ret = -ENOTCONN; 1595 } else { 1596 sock->sk->sk_user_data = queue; 1597 queue->data_ready = sock->sk->sk_data_ready; 1598 sock->sk->sk_data_ready = nvmet_tcp_data_ready; 1599 queue->state_change = sock->sk->sk_state_change; 1600 sock->sk->sk_state_change = nvmet_tcp_state_change; 1601 queue->write_space = sock->sk->sk_write_space; 1602 sock->sk->sk_write_space = nvmet_tcp_write_space; 1603 if (idle_poll_period_usecs) 1604 nvmet_tcp_arm_queue_deadline(queue); 1605 queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work); 1606 } 1607 write_unlock_bh(&sock->sk->sk_callback_lock); 1608 1609 return ret; 1610 } 1611 1612 static int nvmet_tcp_alloc_queue(struct nvmet_tcp_port *port, 1613 struct socket *newsock) 1614 { 1615 struct nvmet_tcp_queue *queue; 1616 int ret; 1617 1618 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 1619 if (!queue) 1620 return -ENOMEM; 1621 1622 INIT_WORK(&queue->release_work, nvmet_tcp_release_queue_work); 1623 INIT_WORK(&queue->io_work, nvmet_tcp_io_work); 1624 queue->sock = newsock; 1625 queue->port = port; 1626 queue->nr_cmds = 0; 1627 spin_lock_init(&queue->state_lock); 1628 queue->state = NVMET_TCP_Q_CONNECTING; 1629 INIT_LIST_HEAD(&queue->free_list); 1630 init_llist_head(&queue->resp_list); 1631 INIT_LIST_HEAD(&queue->resp_send_list); 1632 1633 queue->idx = ida_alloc(&nvmet_tcp_queue_ida, GFP_KERNEL); 1634 if (queue->idx < 0) { 1635 ret = queue->idx; 1636 goto out_free_queue; 1637 } 1638 1639 ret = nvmet_tcp_alloc_cmd(queue, &queue->connect); 1640 if (ret) 1641 goto out_ida_remove; 1642 1643 ret = nvmet_sq_init(&queue->nvme_sq); 1644 if (ret) 1645 goto out_free_connect; 1646 1647 nvmet_prepare_receive_pdu(queue); 1648 1649 mutex_lock(&nvmet_tcp_queue_mutex); 1650 list_add_tail(&queue->queue_list, &nvmet_tcp_queue_list); 1651 mutex_unlock(&nvmet_tcp_queue_mutex); 1652 1653 ret = nvmet_tcp_set_queue_sock(queue); 1654 if (ret) 1655 goto out_destroy_sq; 1656 1657 return 0; 1658 out_destroy_sq: 1659 mutex_lock(&nvmet_tcp_queue_mutex); 1660 list_del_init(&queue->queue_list); 1661 mutex_unlock(&nvmet_tcp_queue_mutex); 1662 nvmet_sq_destroy(&queue->nvme_sq); 1663 out_free_connect: 1664 nvmet_tcp_free_cmd(&queue->connect); 1665 out_ida_remove: 1666 ida_free(&nvmet_tcp_queue_ida, queue->idx); 1667 out_free_queue: 1668 kfree(queue); 1669 return ret; 1670 } 1671 1672 static void nvmet_tcp_accept_work(struct work_struct *w) 1673 { 1674 struct nvmet_tcp_port *port = 1675 container_of(w, struct nvmet_tcp_port, accept_work); 1676 struct socket *newsock; 1677 int ret; 1678 1679 while (true) { 1680 ret = kernel_accept(port->sock, &newsock, O_NONBLOCK); 1681 if (ret < 0) { 1682 if (ret != -EAGAIN) 1683 pr_warn("failed to accept err=%d\n", ret); 1684 return; 1685 } 1686 ret = nvmet_tcp_alloc_queue(port, newsock); 1687 if (ret) { 1688 pr_err("failed to allocate queue\n"); 1689 sock_release(newsock); 1690 } 1691 } 1692 } 1693 1694 static void nvmet_tcp_listen_data_ready(struct sock *sk) 1695 { 1696 struct nvmet_tcp_port *port; 1697 1698 trace_sk_data_ready(sk); 1699 1700 read_lock_bh(&sk->sk_callback_lock); 1701 port = sk->sk_user_data; 1702 if (!port) 1703 goto out; 1704 1705 if (sk->sk_state == TCP_LISTEN) 1706 queue_work(nvmet_wq, &port->accept_work); 1707 out: 1708 read_unlock_bh(&sk->sk_callback_lock); 1709 } 1710 1711 static int nvmet_tcp_add_port(struct nvmet_port *nport) 1712 { 1713 struct nvmet_tcp_port *port; 1714 __kernel_sa_family_t af; 1715 int ret; 1716 1717 port = kzalloc(sizeof(*port), GFP_KERNEL); 1718 if (!port) 1719 return -ENOMEM; 1720 1721 switch (nport->disc_addr.adrfam) { 1722 case NVMF_ADDR_FAMILY_IP4: 1723 af = AF_INET; 1724 break; 1725 case NVMF_ADDR_FAMILY_IP6: 1726 af = AF_INET6; 1727 break; 1728 default: 1729 pr_err("address family %d not supported\n", 1730 nport->disc_addr.adrfam); 1731 ret = -EINVAL; 1732 goto err_port; 1733 } 1734 1735 ret = inet_pton_with_scope(&init_net, af, nport->disc_addr.traddr, 1736 nport->disc_addr.trsvcid, &port->addr); 1737 if (ret) { 1738 pr_err("malformed ip/port passed: %s:%s\n", 1739 nport->disc_addr.traddr, nport->disc_addr.trsvcid); 1740 goto err_port; 1741 } 1742 1743 port->nport = nport; 1744 INIT_WORK(&port->accept_work, nvmet_tcp_accept_work); 1745 if (port->nport->inline_data_size < 0) 1746 port->nport->inline_data_size = NVMET_TCP_DEF_INLINE_DATA_SIZE; 1747 1748 ret = sock_create(port->addr.ss_family, SOCK_STREAM, 1749 IPPROTO_TCP, &port->sock); 1750 if (ret) { 1751 pr_err("failed to create a socket\n"); 1752 goto err_port; 1753 } 1754 1755 port->sock->sk->sk_user_data = port; 1756 port->data_ready = port->sock->sk->sk_data_ready; 1757 port->sock->sk->sk_data_ready = nvmet_tcp_listen_data_ready; 1758 sock_set_reuseaddr(port->sock->sk); 1759 tcp_sock_set_nodelay(port->sock->sk); 1760 if (so_priority > 0) 1761 sock_set_priority(port->sock->sk, so_priority); 1762 1763 ret = kernel_bind(port->sock, (struct sockaddr *)&port->addr, 1764 sizeof(port->addr)); 1765 if (ret) { 1766 pr_err("failed to bind port socket %d\n", ret); 1767 goto err_sock; 1768 } 1769 1770 ret = kernel_listen(port->sock, 128); 1771 if (ret) { 1772 pr_err("failed to listen %d on port sock\n", ret); 1773 goto err_sock; 1774 } 1775 1776 nport->priv = port; 1777 pr_info("enabling port %d (%pISpc)\n", 1778 le16_to_cpu(nport->disc_addr.portid), &port->addr); 1779 1780 return 0; 1781 1782 err_sock: 1783 sock_release(port->sock); 1784 err_port: 1785 kfree(port); 1786 return ret; 1787 } 1788 1789 static void nvmet_tcp_destroy_port_queues(struct nvmet_tcp_port *port) 1790 { 1791 struct nvmet_tcp_queue *queue; 1792 1793 mutex_lock(&nvmet_tcp_queue_mutex); 1794 list_for_each_entry(queue, &nvmet_tcp_queue_list, queue_list) 1795 if (queue->port == port) 1796 kernel_sock_shutdown(queue->sock, SHUT_RDWR); 1797 mutex_unlock(&nvmet_tcp_queue_mutex); 1798 } 1799 1800 static void nvmet_tcp_remove_port(struct nvmet_port *nport) 1801 { 1802 struct nvmet_tcp_port *port = nport->priv; 1803 1804 write_lock_bh(&port->sock->sk->sk_callback_lock); 1805 port->sock->sk->sk_data_ready = port->data_ready; 1806 port->sock->sk->sk_user_data = NULL; 1807 write_unlock_bh(&port->sock->sk->sk_callback_lock); 1808 cancel_work_sync(&port->accept_work); 1809 /* 1810 * Destroy the remaining queues, which are not belong to any 1811 * controller yet. 1812 */ 1813 nvmet_tcp_destroy_port_queues(port); 1814 1815 sock_release(port->sock); 1816 kfree(port); 1817 } 1818 1819 static void nvmet_tcp_delete_ctrl(struct nvmet_ctrl *ctrl) 1820 { 1821 struct nvmet_tcp_queue *queue; 1822 1823 mutex_lock(&nvmet_tcp_queue_mutex); 1824 list_for_each_entry(queue, &nvmet_tcp_queue_list, queue_list) 1825 if (queue->nvme_sq.ctrl == ctrl) 1826 kernel_sock_shutdown(queue->sock, SHUT_RDWR); 1827 mutex_unlock(&nvmet_tcp_queue_mutex); 1828 } 1829 1830 static u16 nvmet_tcp_install_queue(struct nvmet_sq *sq) 1831 { 1832 struct nvmet_tcp_queue *queue = 1833 container_of(sq, struct nvmet_tcp_queue, nvme_sq); 1834 1835 if (sq->qid == 0) { 1836 /* Let inflight controller teardown complete */ 1837 flush_workqueue(nvmet_wq); 1838 } 1839 1840 queue->nr_cmds = sq->size * 2; 1841 if (nvmet_tcp_alloc_cmds(queue)) 1842 return NVME_SC_INTERNAL; 1843 return 0; 1844 } 1845 1846 static void nvmet_tcp_disc_port_addr(struct nvmet_req *req, 1847 struct nvmet_port *nport, char *traddr) 1848 { 1849 struct nvmet_tcp_port *port = nport->priv; 1850 1851 if (inet_addr_is_any((struct sockaddr *)&port->addr)) { 1852 struct nvmet_tcp_cmd *cmd = 1853 container_of(req, struct nvmet_tcp_cmd, req); 1854 struct nvmet_tcp_queue *queue = cmd->queue; 1855 1856 sprintf(traddr, "%pISc", (struct sockaddr *)&queue->sockaddr); 1857 } else { 1858 memcpy(traddr, nport->disc_addr.traddr, NVMF_TRADDR_SIZE); 1859 } 1860 } 1861 1862 static const struct nvmet_fabrics_ops nvmet_tcp_ops = { 1863 .owner = THIS_MODULE, 1864 .type = NVMF_TRTYPE_TCP, 1865 .msdbd = 1, 1866 .add_port = nvmet_tcp_add_port, 1867 .remove_port = nvmet_tcp_remove_port, 1868 .queue_response = nvmet_tcp_queue_response, 1869 .delete_ctrl = nvmet_tcp_delete_ctrl, 1870 .install_queue = nvmet_tcp_install_queue, 1871 .disc_traddr = nvmet_tcp_disc_port_addr, 1872 }; 1873 1874 static int __init nvmet_tcp_init(void) 1875 { 1876 int ret; 1877 1878 nvmet_tcp_wq = alloc_workqueue("nvmet_tcp_wq", 1879 WQ_MEM_RECLAIM | WQ_HIGHPRI, 0); 1880 if (!nvmet_tcp_wq) 1881 return -ENOMEM; 1882 1883 ret = nvmet_register_transport(&nvmet_tcp_ops); 1884 if (ret) 1885 goto err; 1886 1887 return 0; 1888 err: 1889 destroy_workqueue(nvmet_tcp_wq); 1890 return ret; 1891 } 1892 1893 static void __exit nvmet_tcp_exit(void) 1894 { 1895 struct nvmet_tcp_queue *queue; 1896 1897 nvmet_unregister_transport(&nvmet_tcp_ops); 1898 1899 flush_workqueue(nvmet_wq); 1900 mutex_lock(&nvmet_tcp_queue_mutex); 1901 list_for_each_entry(queue, &nvmet_tcp_queue_list, queue_list) 1902 kernel_sock_shutdown(queue->sock, SHUT_RDWR); 1903 mutex_unlock(&nvmet_tcp_queue_mutex); 1904 flush_workqueue(nvmet_wq); 1905 1906 destroy_workqueue(nvmet_tcp_wq); 1907 } 1908 1909 module_init(nvmet_tcp_init); 1910 module_exit(nvmet_tcp_exit); 1911 1912 MODULE_LICENSE("GPL v2"); 1913 MODULE_ALIAS("nvmet-transport-3"); /* 3 == NVMF_TRTYPE_TCP */ 1914