xref: /linux/drivers/nvme/target/tcp.c (revision f2527d8f566a45fa00ee5abd04d1c9476d4d704f)
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 
18 #include "nvmet.h"
19 
20 #define NVMET_TCP_DEF_INLINE_DATA_SIZE	(4 * PAGE_SIZE)
21 
22 /* Define the socket priority to use for connections were it is desirable
23  * that the NIC consider performing optimized packet processing or filtering.
24  * A non-zero value being sufficient to indicate general consideration of any
25  * possible optimization.  Making it a module param allows for alternative
26  * values that may be unique for some NIC implementations.
27  */
28 static int so_priority;
29 module_param(so_priority, int, 0644);
30 MODULE_PARM_DESC(so_priority, "nvmet tcp socket optimize priority");
31 
32 /* Define a time period (in usecs) that io_work() shall sample an activated
33  * queue before determining it to be idle.  This optional module behavior
34  * can enable NIC solutions that support socket optimized packet processing
35  * using advanced interrupt moderation techniques.
36  */
37 static int idle_poll_period_usecs;
38 module_param(idle_poll_period_usecs, int, 0644);
39 MODULE_PARM_DESC(idle_poll_period_usecs,
40 		"nvmet tcp io_work poll till idle time period in usecs");
41 
42 #define NVMET_TCP_RECV_BUDGET		8
43 #define NVMET_TCP_SEND_BUDGET		8
44 #define NVMET_TCP_IO_WORK_BUDGET	64
45 
46 enum nvmet_tcp_send_state {
47 	NVMET_TCP_SEND_DATA_PDU,
48 	NVMET_TCP_SEND_DATA,
49 	NVMET_TCP_SEND_R2T,
50 	NVMET_TCP_SEND_DDGST,
51 	NVMET_TCP_SEND_RESPONSE
52 };
53 
54 enum nvmet_tcp_recv_state {
55 	NVMET_TCP_RECV_PDU,
56 	NVMET_TCP_RECV_DATA,
57 	NVMET_TCP_RECV_DDGST,
58 	NVMET_TCP_RECV_ERR,
59 };
60 
61 enum {
62 	NVMET_TCP_F_INIT_FAILED = (1 << 0),
63 };
64 
65 struct nvmet_tcp_cmd {
66 	struct nvmet_tcp_queue		*queue;
67 	struct nvmet_req		req;
68 
69 	struct nvme_tcp_cmd_pdu		*cmd_pdu;
70 	struct nvme_tcp_rsp_pdu		*rsp_pdu;
71 	struct nvme_tcp_data_pdu	*data_pdu;
72 	struct nvme_tcp_r2t_pdu		*r2t_pdu;
73 
74 	u32				rbytes_done;
75 	u32				wbytes_done;
76 
77 	u32				pdu_len;
78 	u32				pdu_recv;
79 	int				sg_idx;
80 	struct msghdr			recv_msg;
81 	struct bio_vec			*iov;
82 	u32				flags;
83 
84 	struct list_head		entry;
85 	struct llist_node		lentry;
86 
87 	/* send state */
88 	u32				offset;
89 	struct scatterlist		*cur_sg;
90 	enum nvmet_tcp_send_state	state;
91 
92 	__le32				exp_ddgst;
93 	__le32				recv_ddgst;
94 };
95 
96 enum nvmet_tcp_queue_state {
97 	NVMET_TCP_Q_CONNECTING,
98 	NVMET_TCP_Q_LIVE,
99 	NVMET_TCP_Q_DISCONNECTING,
100 };
101 
102 struct nvmet_tcp_queue {
103 	struct socket		*sock;
104 	struct nvmet_tcp_port	*port;
105 	struct work_struct	io_work;
106 	struct nvmet_cq		nvme_cq;
107 	struct nvmet_sq		nvme_sq;
108 
109 	/* send state */
110 	struct nvmet_tcp_cmd	*cmds;
111 	unsigned int		nr_cmds;
112 	struct list_head	free_list;
113 	struct llist_head	resp_list;
114 	struct list_head	resp_send_list;
115 	int			send_list_len;
116 	struct nvmet_tcp_cmd	*snd_cmd;
117 
118 	/* recv state */
119 	int			offset;
120 	int			left;
121 	enum nvmet_tcp_recv_state rcv_state;
122 	struct nvmet_tcp_cmd	*cmd;
123 	union nvme_tcp_pdu	pdu;
124 
125 	/* digest state */
126 	bool			hdr_digest;
127 	bool			data_digest;
128 	struct ahash_request	*snd_hash;
129 	struct ahash_request	*rcv_hash;
130 
131 	unsigned long           poll_end;
132 
133 	spinlock_t		state_lock;
134 	enum nvmet_tcp_queue_state state;
135 
136 	struct sockaddr_storage	sockaddr;
137 	struct sockaddr_storage	sockaddr_peer;
138 	struct work_struct	release_work;
139 
140 	int			idx;
141 	struct list_head	queue_list;
142 
143 	struct nvmet_tcp_cmd	connect;
144 
145 	struct page_frag_cache	pf_cache;
146 
147 	void (*data_ready)(struct sock *);
148 	void (*state_change)(struct sock *);
149 	void (*write_space)(struct sock *);
150 };
151 
152 struct nvmet_tcp_port {
153 	struct socket		*sock;
154 	struct work_struct	accept_work;
155 	struct nvmet_port	*nport;
156 	struct sockaddr_storage addr;
157 	void (*data_ready)(struct sock *);
158 };
159 
160 static DEFINE_IDA(nvmet_tcp_queue_ida);
161 static LIST_HEAD(nvmet_tcp_queue_list);
162 static DEFINE_MUTEX(nvmet_tcp_queue_mutex);
163 
164 static struct workqueue_struct *nvmet_tcp_wq;
165 static const struct nvmet_fabrics_ops nvmet_tcp_ops;
166 static void nvmet_tcp_free_cmd(struct nvmet_tcp_cmd *c);
167 static void nvmet_tcp_free_cmd_buffers(struct nvmet_tcp_cmd *cmd);
168 
169 static inline u16 nvmet_tcp_cmd_tag(struct nvmet_tcp_queue *queue,
170 		struct nvmet_tcp_cmd *cmd)
171 {
172 	if (unlikely(!queue->nr_cmds)) {
173 		/* We didn't allocate cmds yet, send 0xffff */
174 		return USHRT_MAX;
175 	}
176 
177 	return cmd - queue->cmds;
178 }
179 
180 static inline bool nvmet_tcp_has_data_in(struct nvmet_tcp_cmd *cmd)
181 {
182 	return nvme_is_write(cmd->req.cmd) &&
183 		cmd->rbytes_done < cmd->req.transfer_len;
184 }
185 
186 static inline bool nvmet_tcp_need_data_in(struct nvmet_tcp_cmd *cmd)
187 {
188 	return nvmet_tcp_has_data_in(cmd) && !cmd->req.cqe->status;
189 }
190 
191 static inline bool nvmet_tcp_need_data_out(struct nvmet_tcp_cmd *cmd)
192 {
193 	return !nvme_is_write(cmd->req.cmd) &&
194 		cmd->req.transfer_len > 0 &&
195 		!cmd->req.cqe->status;
196 }
197 
198 static inline bool nvmet_tcp_has_inline_data(struct nvmet_tcp_cmd *cmd)
199 {
200 	return nvme_is_write(cmd->req.cmd) && cmd->pdu_len &&
201 		!cmd->rbytes_done;
202 }
203 
204 static inline struct nvmet_tcp_cmd *
205 nvmet_tcp_get_cmd(struct nvmet_tcp_queue *queue)
206 {
207 	struct nvmet_tcp_cmd *cmd;
208 
209 	cmd = list_first_entry_or_null(&queue->free_list,
210 				struct nvmet_tcp_cmd, entry);
211 	if (!cmd)
212 		return NULL;
213 	list_del_init(&cmd->entry);
214 
215 	cmd->rbytes_done = cmd->wbytes_done = 0;
216 	cmd->pdu_len = 0;
217 	cmd->pdu_recv = 0;
218 	cmd->iov = NULL;
219 	cmd->flags = 0;
220 	return cmd;
221 }
222 
223 static inline void nvmet_tcp_put_cmd(struct nvmet_tcp_cmd *cmd)
224 {
225 	if (unlikely(cmd == &cmd->queue->connect))
226 		return;
227 
228 	list_add_tail(&cmd->entry, &cmd->queue->free_list);
229 }
230 
231 static inline int queue_cpu(struct nvmet_tcp_queue *queue)
232 {
233 	return queue->sock->sk->sk_incoming_cpu;
234 }
235 
236 static inline u8 nvmet_tcp_hdgst_len(struct nvmet_tcp_queue *queue)
237 {
238 	return queue->hdr_digest ? NVME_TCP_DIGEST_LENGTH : 0;
239 }
240 
241 static inline u8 nvmet_tcp_ddgst_len(struct nvmet_tcp_queue *queue)
242 {
243 	return queue->data_digest ? NVME_TCP_DIGEST_LENGTH : 0;
244 }
245 
246 static inline void nvmet_tcp_hdgst(struct ahash_request *hash,
247 		void *pdu, size_t len)
248 {
249 	struct scatterlist sg;
250 
251 	sg_init_one(&sg, pdu, len);
252 	ahash_request_set_crypt(hash, &sg, pdu + len, len);
253 	crypto_ahash_digest(hash);
254 }
255 
256 static int nvmet_tcp_verify_hdgst(struct nvmet_tcp_queue *queue,
257 	void *pdu, size_t len)
258 {
259 	struct nvme_tcp_hdr *hdr = pdu;
260 	__le32 recv_digest;
261 	__le32 exp_digest;
262 
263 	if (unlikely(!(hdr->flags & NVME_TCP_F_HDGST))) {
264 		pr_err("queue %d: header digest enabled but no header digest\n",
265 			queue->idx);
266 		return -EPROTO;
267 	}
268 
269 	recv_digest = *(__le32 *)(pdu + hdr->hlen);
270 	nvmet_tcp_hdgst(queue->rcv_hash, pdu, len);
271 	exp_digest = *(__le32 *)(pdu + hdr->hlen);
272 	if (recv_digest != exp_digest) {
273 		pr_err("queue %d: header digest error: recv %#x expected %#x\n",
274 			queue->idx, le32_to_cpu(recv_digest),
275 			le32_to_cpu(exp_digest));
276 		return -EPROTO;
277 	}
278 
279 	return 0;
280 }
281 
282 static int nvmet_tcp_check_ddgst(struct nvmet_tcp_queue *queue, void *pdu)
283 {
284 	struct nvme_tcp_hdr *hdr = pdu;
285 	u8 digest_len = nvmet_tcp_hdgst_len(queue);
286 	u32 len;
287 
288 	len = le32_to_cpu(hdr->plen) - hdr->hlen -
289 		(hdr->flags & NVME_TCP_F_HDGST ? digest_len : 0);
290 
291 	if (unlikely(len && !(hdr->flags & NVME_TCP_F_DDGST))) {
292 		pr_err("queue %d: data digest flag is cleared\n", queue->idx);
293 		return -EPROTO;
294 	}
295 
296 	return 0;
297 }
298 
299 static void nvmet_tcp_free_cmd_buffers(struct nvmet_tcp_cmd *cmd)
300 {
301 	kfree(cmd->iov);
302 	sgl_free(cmd->req.sg);
303 	cmd->iov = NULL;
304 	cmd->req.sg = NULL;
305 }
306 
307 static void nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd)
308 {
309 	struct bio_vec *iov = cmd->iov;
310 	struct scatterlist *sg;
311 	u32 length, offset, sg_offset;
312 	int nr_pages;
313 
314 	length = cmd->pdu_len;
315 	nr_pages = DIV_ROUND_UP(length, PAGE_SIZE);
316 	offset = cmd->rbytes_done;
317 	cmd->sg_idx = offset / PAGE_SIZE;
318 	sg_offset = offset % PAGE_SIZE;
319 	sg = &cmd->req.sg[cmd->sg_idx];
320 
321 	while (length) {
322 		u32 iov_len = min_t(u32, length, sg->length - sg_offset);
323 
324 		iov->bv_page = sg_page(sg);
325 		iov->bv_len = sg->length;
326 		iov->bv_offset = sg->offset + sg_offset;
327 
328 		length -= iov_len;
329 		sg = sg_next(sg);
330 		iov++;
331 		sg_offset = 0;
332 	}
333 
334 	iov_iter_bvec(&cmd->recv_msg.msg_iter, ITER_DEST, cmd->iov,
335 		      nr_pages, cmd->pdu_len);
336 }
337 
338 static void nvmet_tcp_fatal_error(struct nvmet_tcp_queue *queue)
339 {
340 	queue->rcv_state = NVMET_TCP_RECV_ERR;
341 	if (queue->nvme_sq.ctrl)
342 		nvmet_ctrl_fatal_error(queue->nvme_sq.ctrl);
343 	else
344 		kernel_sock_shutdown(queue->sock, SHUT_RDWR);
345 }
346 
347 static void nvmet_tcp_socket_error(struct nvmet_tcp_queue *queue, int status)
348 {
349 	if (status == -EPIPE || status == -ECONNRESET)
350 		kernel_sock_shutdown(queue->sock, SHUT_RDWR);
351 	else
352 		nvmet_tcp_fatal_error(queue);
353 }
354 
355 static int nvmet_tcp_map_data(struct nvmet_tcp_cmd *cmd)
356 {
357 	struct nvme_sgl_desc *sgl = &cmd->req.cmd->common.dptr.sgl;
358 	u32 len = le32_to_cpu(sgl->length);
359 
360 	if (!len)
361 		return 0;
362 
363 	if (sgl->type == ((NVME_SGL_FMT_DATA_DESC << 4) |
364 			  NVME_SGL_FMT_OFFSET)) {
365 		if (!nvme_is_write(cmd->req.cmd))
366 			return NVME_SC_INVALID_FIELD | NVME_SC_DNR;
367 
368 		if (len > cmd->req.port->inline_data_size)
369 			return NVME_SC_SGL_INVALID_OFFSET | NVME_SC_DNR;
370 		cmd->pdu_len = len;
371 	}
372 	cmd->req.transfer_len += len;
373 
374 	cmd->req.sg = sgl_alloc(len, GFP_KERNEL, &cmd->req.sg_cnt);
375 	if (!cmd->req.sg)
376 		return NVME_SC_INTERNAL;
377 	cmd->cur_sg = cmd->req.sg;
378 
379 	if (nvmet_tcp_has_data_in(cmd)) {
380 		cmd->iov = kmalloc_array(cmd->req.sg_cnt,
381 				sizeof(*cmd->iov), GFP_KERNEL);
382 		if (!cmd->iov)
383 			goto err;
384 	}
385 
386 	return 0;
387 err:
388 	nvmet_tcp_free_cmd_buffers(cmd);
389 	return NVME_SC_INTERNAL;
390 }
391 
392 static void nvmet_tcp_calc_ddgst(struct ahash_request *hash,
393 		struct nvmet_tcp_cmd *cmd)
394 {
395 	ahash_request_set_crypt(hash, cmd->req.sg,
396 		(void *)&cmd->exp_ddgst, cmd->req.transfer_len);
397 	crypto_ahash_digest(hash);
398 }
399 
400 static void nvmet_setup_c2h_data_pdu(struct nvmet_tcp_cmd *cmd)
401 {
402 	struct nvme_tcp_data_pdu *pdu = cmd->data_pdu;
403 	struct nvmet_tcp_queue *queue = cmd->queue;
404 	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
405 	u8 ddgst = nvmet_tcp_ddgst_len(cmd->queue);
406 
407 	cmd->offset = 0;
408 	cmd->state = NVMET_TCP_SEND_DATA_PDU;
409 
410 	pdu->hdr.type = nvme_tcp_c2h_data;
411 	pdu->hdr.flags = NVME_TCP_F_DATA_LAST | (queue->nvme_sq.sqhd_disabled ?
412 						NVME_TCP_F_DATA_SUCCESS : 0);
413 	pdu->hdr.hlen = sizeof(*pdu);
414 	pdu->hdr.pdo = pdu->hdr.hlen + hdgst;
415 	pdu->hdr.plen =
416 		cpu_to_le32(pdu->hdr.hlen + hdgst +
417 				cmd->req.transfer_len + ddgst);
418 	pdu->command_id = cmd->req.cqe->command_id;
419 	pdu->data_length = cpu_to_le32(cmd->req.transfer_len);
420 	pdu->data_offset = cpu_to_le32(cmd->wbytes_done);
421 
422 	if (queue->data_digest) {
423 		pdu->hdr.flags |= NVME_TCP_F_DDGST;
424 		nvmet_tcp_calc_ddgst(queue->snd_hash, cmd);
425 	}
426 
427 	if (cmd->queue->hdr_digest) {
428 		pdu->hdr.flags |= NVME_TCP_F_HDGST;
429 		nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu));
430 	}
431 }
432 
433 static void nvmet_setup_r2t_pdu(struct nvmet_tcp_cmd *cmd)
434 {
435 	struct nvme_tcp_r2t_pdu *pdu = cmd->r2t_pdu;
436 	struct nvmet_tcp_queue *queue = cmd->queue;
437 	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
438 
439 	cmd->offset = 0;
440 	cmd->state = NVMET_TCP_SEND_R2T;
441 
442 	pdu->hdr.type = nvme_tcp_r2t;
443 	pdu->hdr.flags = 0;
444 	pdu->hdr.hlen = sizeof(*pdu);
445 	pdu->hdr.pdo = 0;
446 	pdu->hdr.plen = cpu_to_le32(pdu->hdr.hlen + hdgst);
447 
448 	pdu->command_id = cmd->req.cmd->common.command_id;
449 	pdu->ttag = nvmet_tcp_cmd_tag(cmd->queue, cmd);
450 	pdu->r2t_length = cpu_to_le32(cmd->req.transfer_len - cmd->rbytes_done);
451 	pdu->r2t_offset = cpu_to_le32(cmd->rbytes_done);
452 	if (cmd->queue->hdr_digest) {
453 		pdu->hdr.flags |= NVME_TCP_F_HDGST;
454 		nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu));
455 	}
456 }
457 
458 static void nvmet_setup_response_pdu(struct nvmet_tcp_cmd *cmd)
459 {
460 	struct nvme_tcp_rsp_pdu *pdu = cmd->rsp_pdu;
461 	struct nvmet_tcp_queue *queue = cmd->queue;
462 	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
463 
464 	cmd->offset = 0;
465 	cmd->state = NVMET_TCP_SEND_RESPONSE;
466 
467 	pdu->hdr.type = nvme_tcp_rsp;
468 	pdu->hdr.flags = 0;
469 	pdu->hdr.hlen = sizeof(*pdu);
470 	pdu->hdr.pdo = 0;
471 	pdu->hdr.plen = cpu_to_le32(pdu->hdr.hlen + hdgst);
472 	if (cmd->queue->hdr_digest) {
473 		pdu->hdr.flags |= NVME_TCP_F_HDGST;
474 		nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu));
475 	}
476 }
477 
478 static void nvmet_tcp_process_resp_list(struct nvmet_tcp_queue *queue)
479 {
480 	struct llist_node *node;
481 	struct nvmet_tcp_cmd *cmd;
482 
483 	for (node = llist_del_all(&queue->resp_list); node; node = node->next) {
484 		cmd = llist_entry(node, struct nvmet_tcp_cmd, lentry);
485 		list_add(&cmd->entry, &queue->resp_send_list);
486 		queue->send_list_len++;
487 	}
488 }
489 
490 static struct nvmet_tcp_cmd *nvmet_tcp_fetch_cmd(struct nvmet_tcp_queue *queue)
491 {
492 	queue->snd_cmd = list_first_entry_or_null(&queue->resp_send_list,
493 				struct nvmet_tcp_cmd, entry);
494 	if (!queue->snd_cmd) {
495 		nvmet_tcp_process_resp_list(queue);
496 		queue->snd_cmd =
497 			list_first_entry_or_null(&queue->resp_send_list,
498 					struct nvmet_tcp_cmd, entry);
499 		if (unlikely(!queue->snd_cmd))
500 			return NULL;
501 	}
502 
503 	list_del_init(&queue->snd_cmd->entry);
504 	queue->send_list_len--;
505 
506 	if (nvmet_tcp_need_data_out(queue->snd_cmd))
507 		nvmet_setup_c2h_data_pdu(queue->snd_cmd);
508 	else if (nvmet_tcp_need_data_in(queue->snd_cmd))
509 		nvmet_setup_r2t_pdu(queue->snd_cmd);
510 	else
511 		nvmet_setup_response_pdu(queue->snd_cmd);
512 
513 	return queue->snd_cmd;
514 }
515 
516 static void nvmet_tcp_queue_response(struct nvmet_req *req)
517 {
518 	struct nvmet_tcp_cmd *cmd =
519 		container_of(req, struct nvmet_tcp_cmd, req);
520 	struct nvmet_tcp_queue	*queue = cmd->queue;
521 	struct nvme_sgl_desc *sgl;
522 	u32 len;
523 
524 	if (unlikely(cmd == queue->cmd)) {
525 		sgl = &cmd->req.cmd->common.dptr.sgl;
526 		len = le32_to_cpu(sgl->length);
527 
528 		/*
529 		 * Wait for inline data before processing the response.
530 		 * Avoid using helpers, this might happen before
531 		 * nvmet_req_init is completed.
532 		 */
533 		if (queue->rcv_state == NVMET_TCP_RECV_PDU &&
534 		    len && len <= cmd->req.port->inline_data_size &&
535 		    nvme_is_write(cmd->req.cmd))
536 			return;
537 	}
538 
539 	llist_add(&cmd->lentry, &queue->resp_list);
540 	queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &cmd->queue->io_work);
541 }
542 
543 static void nvmet_tcp_execute_request(struct nvmet_tcp_cmd *cmd)
544 {
545 	if (unlikely(cmd->flags & NVMET_TCP_F_INIT_FAILED))
546 		nvmet_tcp_queue_response(&cmd->req);
547 	else
548 		cmd->req.execute(&cmd->req);
549 }
550 
551 static int nvmet_try_send_data_pdu(struct nvmet_tcp_cmd *cmd)
552 {
553 	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
554 	int left = sizeof(*cmd->data_pdu) - cmd->offset + hdgst;
555 	int ret;
556 
557 	ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->data_pdu),
558 			offset_in_page(cmd->data_pdu) + cmd->offset,
559 			left, MSG_DONTWAIT | MSG_MORE | MSG_SENDPAGE_NOTLAST);
560 	if (ret <= 0)
561 		return ret;
562 
563 	cmd->offset += ret;
564 	left -= ret;
565 
566 	if (left)
567 		return -EAGAIN;
568 
569 	cmd->state = NVMET_TCP_SEND_DATA;
570 	cmd->offset  = 0;
571 	return 1;
572 }
573 
574 static int nvmet_try_send_data(struct nvmet_tcp_cmd *cmd, bool last_in_batch)
575 {
576 	struct nvmet_tcp_queue *queue = cmd->queue;
577 	int ret;
578 
579 	while (cmd->cur_sg) {
580 		struct page *page = sg_page(cmd->cur_sg);
581 		u32 left = cmd->cur_sg->length - cmd->offset;
582 		int flags = MSG_DONTWAIT;
583 
584 		if ((!last_in_batch && cmd->queue->send_list_len) ||
585 		    cmd->wbytes_done + left < cmd->req.transfer_len ||
586 		    queue->data_digest || !queue->nvme_sq.sqhd_disabled)
587 			flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST;
588 
589 		ret = kernel_sendpage(cmd->queue->sock, page, cmd->offset,
590 					left, flags);
591 		if (ret <= 0)
592 			return ret;
593 
594 		cmd->offset += ret;
595 		cmd->wbytes_done += ret;
596 
597 		/* Done with sg?*/
598 		if (cmd->offset == cmd->cur_sg->length) {
599 			cmd->cur_sg = sg_next(cmd->cur_sg);
600 			cmd->offset = 0;
601 		}
602 	}
603 
604 	if (queue->data_digest) {
605 		cmd->state = NVMET_TCP_SEND_DDGST;
606 		cmd->offset = 0;
607 	} else {
608 		if (queue->nvme_sq.sqhd_disabled) {
609 			cmd->queue->snd_cmd = NULL;
610 			nvmet_tcp_put_cmd(cmd);
611 		} else {
612 			nvmet_setup_response_pdu(cmd);
613 		}
614 	}
615 
616 	if (queue->nvme_sq.sqhd_disabled)
617 		nvmet_tcp_free_cmd_buffers(cmd);
618 
619 	return 1;
620 
621 }
622 
623 static int nvmet_try_send_response(struct nvmet_tcp_cmd *cmd,
624 		bool last_in_batch)
625 {
626 	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
627 	int left = sizeof(*cmd->rsp_pdu) - cmd->offset + hdgst;
628 	int flags = MSG_DONTWAIT;
629 	int ret;
630 
631 	if (!last_in_batch && cmd->queue->send_list_len)
632 		flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST;
633 	else
634 		flags |= MSG_EOR;
635 
636 	ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->rsp_pdu),
637 		offset_in_page(cmd->rsp_pdu) + cmd->offset, left, flags);
638 	if (ret <= 0)
639 		return ret;
640 	cmd->offset += ret;
641 	left -= ret;
642 
643 	if (left)
644 		return -EAGAIN;
645 
646 	nvmet_tcp_free_cmd_buffers(cmd);
647 	cmd->queue->snd_cmd = NULL;
648 	nvmet_tcp_put_cmd(cmd);
649 	return 1;
650 }
651 
652 static int nvmet_try_send_r2t(struct nvmet_tcp_cmd *cmd, bool last_in_batch)
653 {
654 	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
655 	int left = sizeof(*cmd->r2t_pdu) - cmd->offset + hdgst;
656 	int flags = MSG_DONTWAIT;
657 	int ret;
658 
659 	if (!last_in_batch && cmd->queue->send_list_len)
660 		flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST;
661 	else
662 		flags |= MSG_EOR;
663 
664 	ret = kernel_sendpage(cmd->queue->sock, virt_to_page(cmd->r2t_pdu),
665 		offset_in_page(cmd->r2t_pdu) + cmd->offset, left, flags);
666 	if (ret <= 0)
667 		return ret;
668 	cmd->offset += ret;
669 	left -= ret;
670 
671 	if (left)
672 		return -EAGAIN;
673 
674 	cmd->queue->snd_cmd = NULL;
675 	return 1;
676 }
677 
678 static int nvmet_try_send_ddgst(struct nvmet_tcp_cmd *cmd, bool last_in_batch)
679 {
680 	struct nvmet_tcp_queue *queue = cmd->queue;
681 	int left = NVME_TCP_DIGEST_LENGTH - cmd->offset;
682 	struct msghdr msg = { .msg_flags = MSG_DONTWAIT };
683 	struct kvec iov = {
684 		.iov_base = (u8 *)&cmd->exp_ddgst + cmd->offset,
685 		.iov_len = left
686 	};
687 	int ret;
688 
689 	if (!last_in_batch && cmd->queue->send_list_len)
690 		msg.msg_flags |= MSG_MORE;
691 	else
692 		msg.msg_flags |= MSG_EOR;
693 
694 	ret = kernel_sendmsg(queue->sock, &msg, &iov, 1, iov.iov_len);
695 	if (unlikely(ret <= 0))
696 		return ret;
697 
698 	cmd->offset += ret;
699 	left -= ret;
700 
701 	if (left)
702 		return -EAGAIN;
703 
704 	if (queue->nvme_sq.sqhd_disabled) {
705 		cmd->queue->snd_cmd = NULL;
706 		nvmet_tcp_put_cmd(cmd);
707 	} else {
708 		nvmet_setup_response_pdu(cmd);
709 	}
710 	return 1;
711 }
712 
713 static int nvmet_tcp_try_send_one(struct nvmet_tcp_queue *queue,
714 		bool last_in_batch)
715 {
716 	struct nvmet_tcp_cmd *cmd = queue->snd_cmd;
717 	int ret = 0;
718 
719 	if (!cmd || queue->state == NVMET_TCP_Q_DISCONNECTING) {
720 		cmd = nvmet_tcp_fetch_cmd(queue);
721 		if (unlikely(!cmd))
722 			return 0;
723 	}
724 
725 	if (cmd->state == NVMET_TCP_SEND_DATA_PDU) {
726 		ret = nvmet_try_send_data_pdu(cmd);
727 		if (ret <= 0)
728 			goto done_send;
729 	}
730 
731 	if (cmd->state == NVMET_TCP_SEND_DATA) {
732 		ret = nvmet_try_send_data(cmd, last_in_batch);
733 		if (ret <= 0)
734 			goto done_send;
735 	}
736 
737 	if (cmd->state == NVMET_TCP_SEND_DDGST) {
738 		ret = nvmet_try_send_ddgst(cmd, last_in_batch);
739 		if (ret <= 0)
740 			goto done_send;
741 	}
742 
743 	if (cmd->state == NVMET_TCP_SEND_R2T) {
744 		ret = nvmet_try_send_r2t(cmd, last_in_batch);
745 		if (ret <= 0)
746 			goto done_send;
747 	}
748 
749 	if (cmd->state == NVMET_TCP_SEND_RESPONSE)
750 		ret = nvmet_try_send_response(cmd, last_in_batch);
751 
752 done_send:
753 	if (ret < 0) {
754 		if (ret == -EAGAIN)
755 			return 0;
756 		return ret;
757 	}
758 
759 	return 1;
760 }
761 
762 static int nvmet_tcp_try_send(struct nvmet_tcp_queue *queue,
763 		int budget, int *sends)
764 {
765 	int i, ret = 0;
766 
767 	for (i = 0; i < budget; i++) {
768 		ret = nvmet_tcp_try_send_one(queue, i == budget - 1);
769 		if (unlikely(ret < 0)) {
770 			nvmet_tcp_socket_error(queue, ret);
771 			goto done;
772 		} else if (ret == 0) {
773 			break;
774 		}
775 		(*sends)++;
776 	}
777 done:
778 	return ret;
779 }
780 
781 static void nvmet_prepare_receive_pdu(struct nvmet_tcp_queue *queue)
782 {
783 	queue->offset = 0;
784 	queue->left = sizeof(struct nvme_tcp_hdr);
785 	queue->cmd = NULL;
786 	queue->rcv_state = NVMET_TCP_RECV_PDU;
787 }
788 
789 static void nvmet_tcp_free_crypto(struct nvmet_tcp_queue *queue)
790 {
791 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(queue->rcv_hash);
792 
793 	ahash_request_free(queue->rcv_hash);
794 	ahash_request_free(queue->snd_hash);
795 	crypto_free_ahash(tfm);
796 }
797 
798 static int nvmet_tcp_alloc_crypto(struct nvmet_tcp_queue *queue)
799 {
800 	struct crypto_ahash *tfm;
801 
802 	tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC);
803 	if (IS_ERR(tfm))
804 		return PTR_ERR(tfm);
805 
806 	queue->snd_hash = ahash_request_alloc(tfm, GFP_KERNEL);
807 	if (!queue->snd_hash)
808 		goto free_tfm;
809 	ahash_request_set_callback(queue->snd_hash, 0, NULL, NULL);
810 
811 	queue->rcv_hash = ahash_request_alloc(tfm, GFP_KERNEL);
812 	if (!queue->rcv_hash)
813 		goto free_snd_hash;
814 	ahash_request_set_callback(queue->rcv_hash, 0, NULL, NULL);
815 
816 	return 0;
817 free_snd_hash:
818 	ahash_request_free(queue->snd_hash);
819 free_tfm:
820 	crypto_free_ahash(tfm);
821 	return -ENOMEM;
822 }
823 
824 
825 static int nvmet_tcp_handle_icreq(struct nvmet_tcp_queue *queue)
826 {
827 	struct nvme_tcp_icreq_pdu *icreq = &queue->pdu.icreq;
828 	struct nvme_tcp_icresp_pdu *icresp = &queue->pdu.icresp;
829 	struct msghdr msg = {};
830 	struct kvec iov;
831 	int ret;
832 
833 	if (le32_to_cpu(icreq->hdr.plen) != sizeof(struct nvme_tcp_icreq_pdu)) {
834 		pr_err("bad nvme-tcp pdu length (%d)\n",
835 			le32_to_cpu(icreq->hdr.plen));
836 		nvmet_tcp_fatal_error(queue);
837 	}
838 
839 	if (icreq->pfv != NVME_TCP_PFV_1_0) {
840 		pr_err("queue %d: bad pfv %d\n", queue->idx, icreq->pfv);
841 		return -EPROTO;
842 	}
843 
844 	if (icreq->hpda != 0) {
845 		pr_err("queue %d: unsupported hpda %d\n", queue->idx,
846 			icreq->hpda);
847 		return -EPROTO;
848 	}
849 
850 	queue->hdr_digest = !!(icreq->digest & NVME_TCP_HDR_DIGEST_ENABLE);
851 	queue->data_digest = !!(icreq->digest & NVME_TCP_DATA_DIGEST_ENABLE);
852 	if (queue->hdr_digest || queue->data_digest) {
853 		ret = nvmet_tcp_alloc_crypto(queue);
854 		if (ret)
855 			return ret;
856 	}
857 
858 	memset(icresp, 0, sizeof(*icresp));
859 	icresp->hdr.type = nvme_tcp_icresp;
860 	icresp->hdr.hlen = sizeof(*icresp);
861 	icresp->hdr.pdo = 0;
862 	icresp->hdr.plen = cpu_to_le32(icresp->hdr.hlen);
863 	icresp->pfv = cpu_to_le16(NVME_TCP_PFV_1_0);
864 	icresp->maxdata = cpu_to_le32(0x400000); /* 16M arbitrary limit */
865 	icresp->cpda = 0;
866 	if (queue->hdr_digest)
867 		icresp->digest |= NVME_TCP_HDR_DIGEST_ENABLE;
868 	if (queue->data_digest)
869 		icresp->digest |= NVME_TCP_DATA_DIGEST_ENABLE;
870 
871 	iov.iov_base = icresp;
872 	iov.iov_len = sizeof(*icresp);
873 	ret = kernel_sendmsg(queue->sock, &msg, &iov, 1, iov.iov_len);
874 	if (ret < 0)
875 		goto free_crypto;
876 
877 	queue->state = NVMET_TCP_Q_LIVE;
878 	nvmet_prepare_receive_pdu(queue);
879 	return 0;
880 free_crypto:
881 	if (queue->hdr_digest || queue->data_digest)
882 		nvmet_tcp_free_crypto(queue);
883 	return ret;
884 }
885 
886 static void nvmet_tcp_handle_req_failure(struct nvmet_tcp_queue *queue,
887 		struct nvmet_tcp_cmd *cmd, struct nvmet_req *req)
888 {
889 	size_t data_len = le32_to_cpu(req->cmd->common.dptr.sgl.length);
890 	int ret;
891 
892 	/*
893 	 * This command has not been processed yet, hence we are trying to
894 	 * figure out if there is still pending data left to receive. If
895 	 * we don't, we can simply prepare for the next pdu and bail out,
896 	 * otherwise we will need to prepare a buffer and receive the
897 	 * stale data before continuing forward.
898 	 */
899 	if (!nvme_is_write(cmd->req.cmd) || !data_len ||
900 	    data_len > cmd->req.port->inline_data_size) {
901 		nvmet_prepare_receive_pdu(queue);
902 		return;
903 	}
904 
905 	ret = nvmet_tcp_map_data(cmd);
906 	if (unlikely(ret)) {
907 		pr_err("queue %d: failed to map data\n", queue->idx);
908 		nvmet_tcp_fatal_error(queue);
909 		return;
910 	}
911 
912 	queue->rcv_state = NVMET_TCP_RECV_DATA;
913 	nvmet_tcp_build_pdu_iovec(cmd);
914 	cmd->flags |= NVMET_TCP_F_INIT_FAILED;
915 }
916 
917 static int nvmet_tcp_handle_h2c_data_pdu(struct nvmet_tcp_queue *queue)
918 {
919 	struct nvme_tcp_data_pdu *data = &queue->pdu.data;
920 	struct nvmet_tcp_cmd *cmd;
921 
922 	if (likely(queue->nr_cmds)) {
923 		if (unlikely(data->ttag >= queue->nr_cmds)) {
924 			pr_err("queue %d: received out of bound ttag %u, nr_cmds %u\n",
925 				queue->idx, data->ttag, queue->nr_cmds);
926 			nvmet_tcp_fatal_error(queue);
927 			return -EPROTO;
928 		}
929 		cmd = &queue->cmds[data->ttag];
930 	} else {
931 		cmd = &queue->connect;
932 	}
933 
934 	if (le32_to_cpu(data->data_offset) != cmd->rbytes_done) {
935 		pr_err("ttag %u unexpected data offset %u (expected %u)\n",
936 			data->ttag, le32_to_cpu(data->data_offset),
937 			cmd->rbytes_done);
938 		/* FIXME: use path and transport errors */
939 		nvmet_req_complete(&cmd->req,
940 			NVME_SC_INVALID_FIELD | NVME_SC_DNR);
941 		return -EPROTO;
942 	}
943 
944 	cmd->pdu_len = le32_to_cpu(data->data_length);
945 	cmd->pdu_recv = 0;
946 	nvmet_tcp_build_pdu_iovec(cmd);
947 	queue->cmd = cmd;
948 	queue->rcv_state = NVMET_TCP_RECV_DATA;
949 
950 	return 0;
951 }
952 
953 static int nvmet_tcp_done_recv_pdu(struct nvmet_tcp_queue *queue)
954 {
955 	struct nvme_tcp_hdr *hdr = &queue->pdu.cmd.hdr;
956 	struct nvme_command *nvme_cmd = &queue->pdu.cmd.cmd;
957 	struct nvmet_req *req;
958 	int ret;
959 
960 	if (unlikely(queue->state == NVMET_TCP_Q_CONNECTING)) {
961 		if (hdr->type != nvme_tcp_icreq) {
962 			pr_err("unexpected pdu type (%d) before icreq\n",
963 				hdr->type);
964 			nvmet_tcp_fatal_error(queue);
965 			return -EPROTO;
966 		}
967 		return nvmet_tcp_handle_icreq(queue);
968 	}
969 
970 	if (unlikely(hdr->type == nvme_tcp_icreq)) {
971 		pr_err("queue %d: received icreq pdu in state %d\n",
972 			queue->idx, queue->state);
973 		nvmet_tcp_fatal_error(queue);
974 		return -EPROTO;
975 	}
976 
977 	if (hdr->type == nvme_tcp_h2c_data) {
978 		ret = nvmet_tcp_handle_h2c_data_pdu(queue);
979 		if (unlikely(ret))
980 			return ret;
981 		return 0;
982 	}
983 
984 	queue->cmd = nvmet_tcp_get_cmd(queue);
985 	if (unlikely(!queue->cmd)) {
986 		/* This should never happen */
987 		pr_err("queue %d: out of commands (%d) send_list_len: %d, opcode: %d",
988 			queue->idx, queue->nr_cmds, queue->send_list_len,
989 			nvme_cmd->common.opcode);
990 		nvmet_tcp_fatal_error(queue);
991 		return -ENOMEM;
992 	}
993 
994 	req = &queue->cmd->req;
995 	memcpy(req->cmd, nvme_cmd, sizeof(*nvme_cmd));
996 
997 	if (unlikely(!nvmet_req_init(req, &queue->nvme_cq,
998 			&queue->nvme_sq, &nvmet_tcp_ops))) {
999 		pr_err("failed cmd %p id %d opcode %d, data_len: %d\n",
1000 			req->cmd, req->cmd->common.command_id,
1001 			req->cmd->common.opcode,
1002 			le32_to_cpu(req->cmd->common.dptr.sgl.length));
1003 
1004 		nvmet_tcp_handle_req_failure(queue, queue->cmd, req);
1005 		return 0;
1006 	}
1007 
1008 	ret = nvmet_tcp_map_data(queue->cmd);
1009 	if (unlikely(ret)) {
1010 		pr_err("queue %d: failed to map data\n", queue->idx);
1011 		if (nvmet_tcp_has_inline_data(queue->cmd))
1012 			nvmet_tcp_fatal_error(queue);
1013 		else
1014 			nvmet_req_complete(req, ret);
1015 		ret = -EAGAIN;
1016 		goto out;
1017 	}
1018 
1019 	if (nvmet_tcp_need_data_in(queue->cmd)) {
1020 		if (nvmet_tcp_has_inline_data(queue->cmd)) {
1021 			queue->rcv_state = NVMET_TCP_RECV_DATA;
1022 			nvmet_tcp_build_pdu_iovec(queue->cmd);
1023 			return 0;
1024 		}
1025 		/* send back R2T */
1026 		nvmet_tcp_queue_response(&queue->cmd->req);
1027 		goto out;
1028 	}
1029 
1030 	queue->cmd->req.execute(&queue->cmd->req);
1031 out:
1032 	nvmet_prepare_receive_pdu(queue);
1033 	return ret;
1034 }
1035 
1036 static const u8 nvme_tcp_pdu_sizes[] = {
1037 	[nvme_tcp_icreq]	= sizeof(struct nvme_tcp_icreq_pdu),
1038 	[nvme_tcp_cmd]		= sizeof(struct nvme_tcp_cmd_pdu),
1039 	[nvme_tcp_h2c_data]	= sizeof(struct nvme_tcp_data_pdu),
1040 };
1041 
1042 static inline u8 nvmet_tcp_pdu_size(u8 type)
1043 {
1044 	size_t idx = type;
1045 
1046 	return (idx < ARRAY_SIZE(nvme_tcp_pdu_sizes) &&
1047 		nvme_tcp_pdu_sizes[idx]) ?
1048 			nvme_tcp_pdu_sizes[idx] : 0;
1049 }
1050 
1051 static inline bool nvmet_tcp_pdu_valid(u8 type)
1052 {
1053 	switch (type) {
1054 	case nvme_tcp_icreq:
1055 	case nvme_tcp_cmd:
1056 	case nvme_tcp_h2c_data:
1057 		/* fallthru */
1058 		return true;
1059 	}
1060 
1061 	return false;
1062 }
1063 
1064 static int nvmet_tcp_try_recv_pdu(struct nvmet_tcp_queue *queue)
1065 {
1066 	struct nvme_tcp_hdr *hdr = &queue->pdu.cmd.hdr;
1067 	int len;
1068 	struct kvec iov;
1069 	struct msghdr msg = { .msg_flags = MSG_DONTWAIT };
1070 
1071 recv:
1072 	iov.iov_base = (void *)&queue->pdu + queue->offset;
1073 	iov.iov_len = queue->left;
1074 	len = kernel_recvmsg(queue->sock, &msg, &iov, 1,
1075 			iov.iov_len, msg.msg_flags);
1076 	if (unlikely(len < 0))
1077 		return len;
1078 
1079 	queue->offset += len;
1080 	queue->left -= len;
1081 	if (queue->left)
1082 		return -EAGAIN;
1083 
1084 	if (queue->offset == sizeof(struct nvme_tcp_hdr)) {
1085 		u8 hdgst = nvmet_tcp_hdgst_len(queue);
1086 
1087 		if (unlikely(!nvmet_tcp_pdu_valid(hdr->type))) {
1088 			pr_err("unexpected pdu type %d\n", hdr->type);
1089 			nvmet_tcp_fatal_error(queue);
1090 			return -EIO;
1091 		}
1092 
1093 		if (unlikely(hdr->hlen != nvmet_tcp_pdu_size(hdr->type))) {
1094 			pr_err("pdu %d bad hlen %d\n", hdr->type, hdr->hlen);
1095 			return -EIO;
1096 		}
1097 
1098 		queue->left = hdr->hlen - queue->offset + hdgst;
1099 		goto recv;
1100 	}
1101 
1102 	if (queue->hdr_digest &&
1103 	    nvmet_tcp_verify_hdgst(queue, &queue->pdu, hdr->hlen)) {
1104 		nvmet_tcp_fatal_error(queue); /* fatal */
1105 		return -EPROTO;
1106 	}
1107 
1108 	if (queue->data_digest &&
1109 	    nvmet_tcp_check_ddgst(queue, &queue->pdu)) {
1110 		nvmet_tcp_fatal_error(queue); /* fatal */
1111 		return -EPROTO;
1112 	}
1113 
1114 	return nvmet_tcp_done_recv_pdu(queue);
1115 }
1116 
1117 static void nvmet_tcp_prep_recv_ddgst(struct nvmet_tcp_cmd *cmd)
1118 {
1119 	struct nvmet_tcp_queue *queue = cmd->queue;
1120 
1121 	nvmet_tcp_calc_ddgst(queue->rcv_hash, cmd);
1122 	queue->offset = 0;
1123 	queue->left = NVME_TCP_DIGEST_LENGTH;
1124 	queue->rcv_state = NVMET_TCP_RECV_DDGST;
1125 }
1126 
1127 static int nvmet_tcp_try_recv_data(struct nvmet_tcp_queue *queue)
1128 {
1129 	struct nvmet_tcp_cmd  *cmd = queue->cmd;
1130 	int ret;
1131 
1132 	while (msg_data_left(&cmd->recv_msg)) {
1133 		ret = sock_recvmsg(cmd->queue->sock, &cmd->recv_msg,
1134 			cmd->recv_msg.msg_flags);
1135 		if (ret <= 0)
1136 			return ret;
1137 
1138 		cmd->pdu_recv += ret;
1139 		cmd->rbytes_done += ret;
1140 	}
1141 
1142 	if (queue->data_digest) {
1143 		nvmet_tcp_prep_recv_ddgst(cmd);
1144 		return 0;
1145 	}
1146 
1147 	if (cmd->rbytes_done == cmd->req.transfer_len)
1148 		nvmet_tcp_execute_request(cmd);
1149 
1150 	nvmet_prepare_receive_pdu(queue);
1151 	return 0;
1152 }
1153 
1154 static int nvmet_tcp_try_recv_ddgst(struct nvmet_tcp_queue *queue)
1155 {
1156 	struct nvmet_tcp_cmd *cmd = queue->cmd;
1157 	int ret;
1158 	struct msghdr msg = { .msg_flags = MSG_DONTWAIT };
1159 	struct kvec iov = {
1160 		.iov_base = (void *)&cmd->recv_ddgst + queue->offset,
1161 		.iov_len = queue->left
1162 	};
1163 
1164 	ret = kernel_recvmsg(queue->sock, &msg, &iov, 1,
1165 			iov.iov_len, msg.msg_flags);
1166 	if (unlikely(ret < 0))
1167 		return ret;
1168 
1169 	queue->offset += ret;
1170 	queue->left -= ret;
1171 	if (queue->left)
1172 		return -EAGAIN;
1173 
1174 	if (queue->data_digest && cmd->exp_ddgst != cmd->recv_ddgst) {
1175 		pr_err("queue %d: cmd %d pdu (%d) data digest error: recv %#x expected %#x\n",
1176 			queue->idx, cmd->req.cmd->common.command_id,
1177 			queue->pdu.cmd.hdr.type, le32_to_cpu(cmd->recv_ddgst),
1178 			le32_to_cpu(cmd->exp_ddgst));
1179 		nvmet_req_uninit(&cmd->req);
1180 		nvmet_tcp_free_cmd_buffers(cmd);
1181 		nvmet_tcp_fatal_error(queue);
1182 		ret = -EPROTO;
1183 		goto out;
1184 	}
1185 
1186 	if (cmd->rbytes_done == cmd->req.transfer_len)
1187 		nvmet_tcp_execute_request(cmd);
1188 
1189 	ret = 0;
1190 out:
1191 	nvmet_prepare_receive_pdu(queue);
1192 	return ret;
1193 }
1194 
1195 static int nvmet_tcp_try_recv_one(struct nvmet_tcp_queue *queue)
1196 {
1197 	int result = 0;
1198 
1199 	if (unlikely(queue->rcv_state == NVMET_TCP_RECV_ERR))
1200 		return 0;
1201 
1202 	if (queue->rcv_state == NVMET_TCP_RECV_PDU) {
1203 		result = nvmet_tcp_try_recv_pdu(queue);
1204 		if (result != 0)
1205 			goto done_recv;
1206 	}
1207 
1208 	if (queue->rcv_state == NVMET_TCP_RECV_DATA) {
1209 		result = nvmet_tcp_try_recv_data(queue);
1210 		if (result != 0)
1211 			goto done_recv;
1212 	}
1213 
1214 	if (queue->rcv_state == NVMET_TCP_RECV_DDGST) {
1215 		result = nvmet_tcp_try_recv_ddgst(queue);
1216 		if (result != 0)
1217 			goto done_recv;
1218 	}
1219 
1220 done_recv:
1221 	if (result < 0) {
1222 		if (result == -EAGAIN)
1223 			return 0;
1224 		return result;
1225 	}
1226 	return 1;
1227 }
1228 
1229 static int nvmet_tcp_try_recv(struct nvmet_tcp_queue *queue,
1230 		int budget, int *recvs)
1231 {
1232 	int i, ret = 0;
1233 
1234 	for (i = 0; i < budget; i++) {
1235 		ret = nvmet_tcp_try_recv_one(queue);
1236 		if (unlikely(ret < 0)) {
1237 			nvmet_tcp_socket_error(queue, ret);
1238 			goto done;
1239 		} else if (ret == 0) {
1240 			break;
1241 		}
1242 		(*recvs)++;
1243 	}
1244 done:
1245 	return ret;
1246 }
1247 
1248 static void nvmet_tcp_schedule_release_queue(struct nvmet_tcp_queue *queue)
1249 {
1250 	spin_lock(&queue->state_lock);
1251 	if (queue->state != NVMET_TCP_Q_DISCONNECTING) {
1252 		queue->state = NVMET_TCP_Q_DISCONNECTING;
1253 		queue_work(nvmet_wq, &queue->release_work);
1254 	}
1255 	spin_unlock(&queue->state_lock);
1256 }
1257 
1258 static inline void nvmet_tcp_arm_queue_deadline(struct nvmet_tcp_queue *queue)
1259 {
1260 	queue->poll_end = jiffies + usecs_to_jiffies(idle_poll_period_usecs);
1261 }
1262 
1263 static bool nvmet_tcp_check_queue_deadline(struct nvmet_tcp_queue *queue,
1264 		int ops)
1265 {
1266 	if (!idle_poll_period_usecs)
1267 		return false;
1268 
1269 	if (ops)
1270 		nvmet_tcp_arm_queue_deadline(queue);
1271 
1272 	return !time_after(jiffies, queue->poll_end);
1273 }
1274 
1275 static void nvmet_tcp_io_work(struct work_struct *w)
1276 {
1277 	struct nvmet_tcp_queue *queue =
1278 		container_of(w, struct nvmet_tcp_queue, io_work);
1279 	bool pending;
1280 	int ret, ops = 0;
1281 
1282 	do {
1283 		pending = false;
1284 
1285 		ret = nvmet_tcp_try_recv(queue, NVMET_TCP_RECV_BUDGET, &ops);
1286 		if (ret > 0)
1287 			pending = true;
1288 		else if (ret < 0)
1289 			return;
1290 
1291 		ret = nvmet_tcp_try_send(queue, NVMET_TCP_SEND_BUDGET, &ops);
1292 		if (ret > 0)
1293 			pending = true;
1294 		else if (ret < 0)
1295 			return;
1296 
1297 	} while (pending && ops < NVMET_TCP_IO_WORK_BUDGET);
1298 
1299 	/*
1300 	 * Requeue the worker if idle deadline period is in progress or any
1301 	 * ops activity was recorded during the do-while loop above.
1302 	 */
1303 	if (nvmet_tcp_check_queue_deadline(queue, ops) || pending)
1304 		queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work);
1305 }
1306 
1307 static int nvmet_tcp_alloc_cmd(struct nvmet_tcp_queue *queue,
1308 		struct nvmet_tcp_cmd *c)
1309 {
1310 	u8 hdgst = nvmet_tcp_hdgst_len(queue);
1311 
1312 	c->queue = queue;
1313 	c->req.port = queue->port->nport;
1314 
1315 	c->cmd_pdu = page_frag_alloc(&queue->pf_cache,
1316 			sizeof(*c->cmd_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO);
1317 	if (!c->cmd_pdu)
1318 		return -ENOMEM;
1319 	c->req.cmd = &c->cmd_pdu->cmd;
1320 
1321 	c->rsp_pdu = page_frag_alloc(&queue->pf_cache,
1322 			sizeof(*c->rsp_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO);
1323 	if (!c->rsp_pdu)
1324 		goto out_free_cmd;
1325 	c->req.cqe = &c->rsp_pdu->cqe;
1326 
1327 	c->data_pdu = page_frag_alloc(&queue->pf_cache,
1328 			sizeof(*c->data_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO);
1329 	if (!c->data_pdu)
1330 		goto out_free_rsp;
1331 
1332 	c->r2t_pdu = page_frag_alloc(&queue->pf_cache,
1333 			sizeof(*c->r2t_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO);
1334 	if (!c->r2t_pdu)
1335 		goto out_free_data;
1336 
1337 	c->recv_msg.msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL;
1338 
1339 	list_add_tail(&c->entry, &queue->free_list);
1340 
1341 	return 0;
1342 out_free_data:
1343 	page_frag_free(c->data_pdu);
1344 out_free_rsp:
1345 	page_frag_free(c->rsp_pdu);
1346 out_free_cmd:
1347 	page_frag_free(c->cmd_pdu);
1348 	return -ENOMEM;
1349 }
1350 
1351 static void nvmet_tcp_free_cmd(struct nvmet_tcp_cmd *c)
1352 {
1353 	page_frag_free(c->r2t_pdu);
1354 	page_frag_free(c->data_pdu);
1355 	page_frag_free(c->rsp_pdu);
1356 	page_frag_free(c->cmd_pdu);
1357 }
1358 
1359 static int nvmet_tcp_alloc_cmds(struct nvmet_tcp_queue *queue)
1360 {
1361 	struct nvmet_tcp_cmd *cmds;
1362 	int i, ret = -EINVAL, nr_cmds = queue->nr_cmds;
1363 
1364 	cmds = kcalloc(nr_cmds, sizeof(struct nvmet_tcp_cmd), GFP_KERNEL);
1365 	if (!cmds)
1366 		goto out;
1367 
1368 	for (i = 0; i < nr_cmds; i++) {
1369 		ret = nvmet_tcp_alloc_cmd(queue, cmds + i);
1370 		if (ret)
1371 			goto out_free;
1372 	}
1373 
1374 	queue->cmds = cmds;
1375 
1376 	return 0;
1377 out_free:
1378 	while (--i >= 0)
1379 		nvmet_tcp_free_cmd(cmds + i);
1380 	kfree(cmds);
1381 out:
1382 	return ret;
1383 }
1384 
1385 static void nvmet_tcp_free_cmds(struct nvmet_tcp_queue *queue)
1386 {
1387 	struct nvmet_tcp_cmd *cmds = queue->cmds;
1388 	int i;
1389 
1390 	for (i = 0; i < queue->nr_cmds; i++)
1391 		nvmet_tcp_free_cmd(cmds + i);
1392 
1393 	nvmet_tcp_free_cmd(&queue->connect);
1394 	kfree(cmds);
1395 }
1396 
1397 static void nvmet_tcp_restore_socket_callbacks(struct nvmet_tcp_queue *queue)
1398 {
1399 	struct socket *sock = queue->sock;
1400 
1401 	write_lock_bh(&sock->sk->sk_callback_lock);
1402 	sock->sk->sk_data_ready =  queue->data_ready;
1403 	sock->sk->sk_state_change = queue->state_change;
1404 	sock->sk->sk_write_space = queue->write_space;
1405 	sock->sk->sk_user_data = NULL;
1406 	write_unlock_bh(&sock->sk->sk_callback_lock);
1407 }
1408 
1409 static void nvmet_tcp_uninit_data_in_cmds(struct nvmet_tcp_queue *queue)
1410 {
1411 	struct nvmet_tcp_cmd *cmd = queue->cmds;
1412 	int i;
1413 
1414 	for (i = 0; i < queue->nr_cmds; i++, cmd++) {
1415 		if (nvmet_tcp_need_data_in(cmd))
1416 			nvmet_req_uninit(&cmd->req);
1417 	}
1418 
1419 	if (!queue->nr_cmds && nvmet_tcp_need_data_in(&queue->connect)) {
1420 		/* failed in connect */
1421 		nvmet_req_uninit(&queue->connect.req);
1422 	}
1423 }
1424 
1425 static void nvmet_tcp_free_cmd_data_in_buffers(struct nvmet_tcp_queue *queue)
1426 {
1427 	struct nvmet_tcp_cmd *cmd = queue->cmds;
1428 	int i;
1429 
1430 	for (i = 0; i < queue->nr_cmds; i++, cmd++) {
1431 		if (nvmet_tcp_need_data_in(cmd))
1432 			nvmet_tcp_free_cmd_buffers(cmd);
1433 	}
1434 
1435 	if (!queue->nr_cmds && nvmet_tcp_need_data_in(&queue->connect))
1436 		nvmet_tcp_free_cmd_buffers(&queue->connect);
1437 }
1438 
1439 static void nvmet_tcp_release_queue_work(struct work_struct *w)
1440 {
1441 	struct page *page;
1442 	struct nvmet_tcp_queue *queue =
1443 		container_of(w, struct nvmet_tcp_queue, release_work);
1444 
1445 	mutex_lock(&nvmet_tcp_queue_mutex);
1446 	list_del_init(&queue->queue_list);
1447 	mutex_unlock(&nvmet_tcp_queue_mutex);
1448 
1449 	nvmet_tcp_restore_socket_callbacks(queue);
1450 	cancel_work_sync(&queue->io_work);
1451 	/* stop accepting incoming data */
1452 	queue->rcv_state = NVMET_TCP_RECV_ERR;
1453 
1454 	nvmet_tcp_uninit_data_in_cmds(queue);
1455 	nvmet_sq_destroy(&queue->nvme_sq);
1456 	cancel_work_sync(&queue->io_work);
1457 	nvmet_tcp_free_cmd_data_in_buffers(queue);
1458 	sock_release(queue->sock);
1459 	nvmet_tcp_free_cmds(queue);
1460 	if (queue->hdr_digest || queue->data_digest)
1461 		nvmet_tcp_free_crypto(queue);
1462 	ida_free(&nvmet_tcp_queue_ida, queue->idx);
1463 
1464 	page = virt_to_head_page(queue->pf_cache.va);
1465 	__page_frag_cache_drain(page, queue->pf_cache.pagecnt_bias);
1466 	kfree(queue);
1467 }
1468 
1469 static void nvmet_tcp_data_ready(struct sock *sk)
1470 {
1471 	struct nvmet_tcp_queue *queue;
1472 
1473 	read_lock_bh(&sk->sk_callback_lock);
1474 	queue = sk->sk_user_data;
1475 	if (likely(queue))
1476 		queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work);
1477 	read_unlock_bh(&sk->sk_callback_lock);
1478 }
1479 
1480 static void nvmet_tcp_write_space(struct sock *sk)
1481 {
1482 	struct nvmet_tcp_queue *queue;
1483 
1484 	read_lock_bh(&sk->sk_callback_lock);
1485 	queue = sk->sk_user_data;
1486 	if (unlikely(!queue))
1487 		goto out;
1488 
1489 	if (unlikely(queue->state == NVMET_TCP_Q_CONNECTING)) {
1490 		queue->write_space(sk);
1491 		goto out;
1492 	}
1493 
1494 	if (sk_stream_is_writeable(sk)) {
1495 		clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1496 		queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work);
1497 	}
1498 out:
1499 	read_unlock_bh(&sk->sk_callback_lock);
1500 }
1501 
1502 static void nvmet_tcp_state_change(struct sock *sk)
1503 {
1504 	struct nvmet_tcp_queue *queue;
1505 
1506 	read_lock_bh(&sk->sk_callback_lock);
1507 	queue = sk->sk_user_data;
1508 	if (!queue)
1509 		goto done;
1510 
1511 	switch (sk->sk_state) {
1512 	case TCP_FIN_WAIT2:
1513 	case TCP_LAST_ACK:
1514 		break;
1515 	case TCP_FIN_WAIT1:
1516 	case TCP_CLOSE_WAIT:
1517 	case TCP_CLOSE:
1518 		/* FALLTHRU */
1519 		nvmet_tcp_schedule_release_queue(queue);
1520 		break;
1521 	default:
1522 		pr_warn("queue %d unhandled state %d\n",
1523 			queue->idx, sk->sk_state);
1524 	}
1525 done:
1526 	read_unlock_bh(&sk->sk_callback_lock);
1527 }
1528 
1529 static int nvmet_tcp_set_queue_sock(struct nvmet_tcp_queue *queue)
1530 {
1531 	struct socket *sock = queue->sock;
1532 	struct inet_sock *inet = inet_sk(sock->sk);
1533 	int ret;
1534 
1535 	ret = kernel_getsockname(sock,
1536 		(struct sockaddr *)&queue->sockaddr);
1537 	if (ret < 0)
1538 		return ret;
1539 
1540 	ret = kernel_getpeername(sock,
1541 		(struct sockaddr *)&queue->sockaddr_peer);
1542 	if (ret < 0)
1543 		return ret;
1544 
1545 	/*
1546 	 * Cleanup whatever is sitting in the TCP transmit queue on socket
1547 	 * close. This is done to prevent stale data from being sent should
1548 	 * the network connection be restored before TCP times out.
1549 	 */
1550 	sock_no_linger(sock->sk);
1551 
1552 	if (so_priority > 0)
1553 		sock_set_priority(sock->sk, so_priority);
1554 
1555 	/* Set socket type of service */
1556 	if (inet->rcv_tos > 0)
1557 		ip_sock_set_tos(sock->sk, inet->rcv_tos);
1558 
1559 	ret = 0;
1560 	write_lock_bh(&sock->sk->sk_callback_lock);
1561 	if (sock->sk->sk_state != TCP_ESTABLISHED) {
1562 		/*
1563 		 * If the socket is already closing, don't even start
1564 		 * consuming it
1565 		 */
1566 		ret = -ENOTCONN;
1567 	} else {
1568 		sock->sk->sk_user_data = queue;
1569 		queue->data_ready = sock->sk->sk_data_ready;
1570 		sock->sk->sk_data_ready = nvmet_tcp_data_ready;
1571 		queue->state_change = sock->sk->sk_state_change;
1572 		sock->sk->sk_state_change = nvmet_tcp_state_change;
1573 		queue->write_space = sock->sk->sk_write_space;
1574 		sock->sk->sk_write_space = nvmet_tcp_write_space;
1575 		if (idle_poll_period_usecs)
1576 			nvmet_tcp_arm_queue_deadline(queue);
1577 		queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work);
1578 	}
1579 	write_unlock_bh(&sock->sk->sk_callback_lock);
1580 
1581 	return ret;
1582 }
1583 
1584 static int nvmet_tcp_alloc_queue(struct nvmet_tcp_port *port,
1585 		struct socket *newsock)
1586 {
1587 	struct nvmet_tcp_queue *queue;
1588 	int ret;
1589 
1590 	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
1591 	if (!queue)
1592 		return -ENOMEM;
1593 
1594 	INIT_WORK(&queue->release_work, nvmet_tcp_release_queue_work);
1595 	INIT_WORK(&queue->io_work, nvmet_tcp_io_work);
1596 	queue->sock = newsock;
1597 	queue->port = port;
1598 	queue->nr_cmds = 0;
1599 	spin_lock_init(&queue->state_lock);
1600 	queue->state = NVMET_TCP_Q_CONNECTING;
1601 	INIT_LIST_HEAD(&queue->free_list);
1602 	init_llist_head(&queue->resp_list);
1603 	INIT_LIST_HEAD(&queue->resp_send_list);
1604 
1605 	queue->idx = ida_alloc(&nvmet_tcp_queue_ida, GFP_KERNEL);
1606 	if (queue->idx < 0) {
1607 		ret = queue->idx;
1608 		goto out_free_queue;
1609 	}
1610 
1611 	ret = nvmet_tcp_alloc_cmd(queue, &queue->connect);
1612 	if (ret)
1613 		goto out_ida_remove;
1614 
1615 	ret = nvmet_sq_init(&queue->nvme_sq);
1616 	if (ret)
1617 		goto out_free_connect;
1618 
1619 	nvmet_prepare_receive_pdu(queue);
1620 
1621 	mutex_lock(&nvmet_tcp_queue_mutex);
1622 	list_add_tail(&queue->queue_list, &nvmet_tcp_queue_list);
1623 	mutex_unlock(&nvmet_tcp_queue_mutex);
1624 
1625 	ret = nvmet_tcp_set_queue_sock(queue);
1626 	if (ret)
1627 		goto out_destroy_sq;
1628 
1629 	return 0;
1630 out_destroy_sq:
1631 	mutex_lock(&nvmet_tcp_queue_mutex);
1632 	list_del_init(&queue->queue_list);
1633 	mutex_unlock(&nvmet_tcp_queue_mutex);
1634 	nvmet_sq_destroy(&queue->nvme_sq);
1635 out_free_connect:
1636 	nvmet_tcp_free_cmd(&queue->connect);
1637 out_ida_remove:
1638 	ida_free(&nvmet_tcp_queue_ida, queue->idx);
1639 out_free_queue:
1640 	kfree(queue);
1641 	return ret;
1642 }
1643 
1644 static void nvmet_tcp_accept_work(struct work_struct *w)
1645 {
1646 	struct nvmet_tcp_port *port =
1647 		container_of(w, struct nvmet_tcp_port, accept_work);
1648 	struct socket *newsock;
1649 	int ret;
1650 
1651 	while (true) {
1652 		ret = kernel_accept(port->sock, &newsock, O_NONBLOCK);
1653 		if (ret < 0) {
1654 			if (ret != -EAGAIN)
1655 				pr_warn("failed to accept err=%d\n", ret);
1656 			return;
1657 		}
1658 		ret = nvmet_tcp_alloc_queue(port, newsock);
1659 		if (ret) {
1660 			pr_err("failed to allocate queue\n");
1661 			sock_release(newsock);
1662 		}
1663 	}
1664 }
1665 
1666 static void nvmet_tcp_listen_data_ready(struct sock *sk)
1667 {
1668 	struct nvmet_tcp_port *port;
1669 
1670 	read_lock_bh(&sk->sk_callback_lock);
1671 	port = sk->sk_user_data;
1672 	if (!port)
1673 		goto out;
1674 
1675 	if (sk->sk_state == TCP_LISTEN)
1676 		queue_work(nvmet_wq, &port->accept_work);
1677 out:
1678 	read_unlock_bh(&sk->sk_callback_lock);
1679 }
1680 
1681 static int nvmet_tcp_add_port(struct nvmet_port *nport)
1682 {
1683 	struct nvmet_tcp_port *port;
1684 	__kernel_sa_family_t af;
1685 	int ret;
1686 
1687 	port = kzalloc(sizeof(*port), GFP_KERNEL);
1688 	if (!port)
1689 		return -ENOMEM;
1690 
1691 	switch (nport->disc_addr.adrfam) {
1692 	case NVMF_ADDR_FAMILY_IP4:
1693 		af = AF_INET;
1694 		break;
1695 	case NVMF_ADDR_FAMILY_IP6:
1696 		af = AF_INET6;
1697 		break;
1698 	default:
1699 		pr_err("address family %d not supported\n",
1700 				nport->disc_addr.adrfam);
1701 		ret = -EINVAL;
1702 		goto err_port;
1703 	}
1704 
1705 	ret = inet_pton_with_scope(&init_net, af, nport->disc_addr.traddr,
1706 			nport->disc_addr.trsvcid, &port->addr);
1707 	if (ret) {
1708 		pr_err("malformed ip/port passed: %s:%s\n",
1709 			nport->disc_addr.traddr, nport->disc_addr.trsvcid);
1710 		goto err_port;
1711 	}
1712 
1713 	port->nport = nport;
1714 	INIT_WORK(&port->accept_work, nvmet_tcp_accept_work);
1715 	if (port->nport->inline_data_size < 0)
1716 		port->nport->inline_data_size = NVMET_TCP_DEF_INLINE_DATA_SIZE;
1717 
1718 	ret = sock_create(port->addr.ss_family, SOCK_STREAM,
1719 				IPPROTO_TCP, &port->sock);
1720 	if (ret) {
1721 		pr_err("failed to create a socket\n");
1722 		goto err_port;
1723 	}
1724 
1725 	port->sock->sk->sk_user_data = port;
1726 	port->data_ready = port->sock->sk->sk_data_ready;
1727 	port->sock->sk->sk_data_ready = nvmet_tcp_listen_data_ready;
1728 	sock_set_reuseaddr(port->sock->sk);
1729 	tcp_sock_set_nodelay(port->sock->sk);
1730 	if (so_priority > 0)
1731 		sock_set_priority(port->sock->sk, so_priority);
1732 
1733 	ret = kernel_bind(port->sock, (struct sockaddr *)&port->addr,
1734 			sizeof(port->addr));
1735 	if (ret) {
1736 		pr_err("failed to bind port socket %d\n", ret);
1737 		goto err_sock;
1738 	}
1739 
1740 	ret = kernel_listen(port->sock, 128);
1741 	if (ret) {
1742 		pr_err("failed to listen %d on port sock\n", ret);
1743 		goto err_sock;
1744 	}
1745 
1746 	nport->priv = port;
1747 	pr_info("enabling port %d (%pISpc)\n",
1748 		le16_to_cpu(nport->disc_addr.portid), &port->addr);
1749 
1750 	return 0;
1751 
1752 err_sock:
1753 	sock_release(port->sock);
1754 err_port:
1755 	kfree(port);
1756 	return ret;
1757 }
1758 
1759 static void nvmet_tcp_destroy_port_queues(struct nvmet_tcp_port *port)
1760 {
1761 	struct nvmet_tcp_queue *queue;
1762 
1763 	mutex_lock(&nvmet_tcp_queue_mutex);
1764 	list_for_each_entry(queue, &nvmet_tcp_queue_list, queue_list)
1765 		if (queue->port == port)
1766 			kernel_sock_shutdown(queue->sock, SHUT_RDWR);
1767 	mutex_unlock(&nvmet_tcp_queue_mutex);
1768 }
1769 
1770 static void nvmet_tcp_remove_port(struct nvmet_port *nport)
1771 {
1772 	struct nvmet_tcp_port *port = nport->priv;
1773 
1774 	write_lock_bh(&port->sock->sk->sk_callback_lock);
1775 	port->sock->sk->sk_data_ready = port->data_ready;
1776 	port->sock->sk->sk_user_data = NULL;
1777 	write_unlock_bh(&port->sock->sk->sk_callback_lock);
1778 	cancel_work_sync(&port->accept_work);
1779 	/*
1780 	 * Destroy the remaining queues, which are not belong to any
1781 	 * controller yet.
1782 	 */
1783 	nvmet_tcp_destroy_port_queues(port);
1784 
1785 	sock_release(port->sock);
1786 	kfree(port);
1787 }
1788 
1789 static void nvmet_tcp_delete_ctrl(struct nvmet_ctrl *ctrl)
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->nvme_sq.ctrl == ctrl)
1796 			kernel_sock_shutdown(queue->sock, SHUT_RDWR);
1797 	mutex_unlock(&nvmet_tcp_queue_mutex);
1798 }
1799 
1800 static u16 nvmet_tcp_install_queue(struct nvmet_sq *sq)
1801 {
1802 	struct nvmet_tcp_queue *queue =
1803 		container_of(sq, struct nvmet_tcp_queue, nvme_sq);
1804 
1805 	if (sq->qid == 0) {
1806 		/* Let inflight controller teardown complete */
1807 		flush_workqueue(nvmet_wq);
1808 	}
1809 
1810 	queue->nr_cmds = sq->size * 2;
1811 	if (nvmet_tcp_alloc_cmds(queue))
1812 		return NVME_SC_INTERNAL;
1813 	return 0;
1814 }
1815 
1816 static void nvmet_tcp_disc_port_addr(struct nvmet_req *req,
1817 		struct nvmet_port *nport, char *traddr)
1818 {
1819 	struct nvmet_tcp_port *port = nport->priv;
1820 
1821 	if (inet_addr_is_any((struct sockaddr *)&port->addr)) {
1822 		struct nvmet_tcp_cmd *cmd =
1823 			container_of(req, struct nvmet_tcp_cmd, req);
1824 		struct nvmet_tcp_queue *queue = cmd->queue;
1825 
1826 		sprintf(traddr, "%pISc", (struct sockaddr *)&queue->sockaddr);
1827 	} else {
1828 		memcpy(traddr, nport->disc_addr.traddr, NVMF_TRADDR_SIZE);
1829 	}
1830 }
1831 
1832 static const struct nvmet_fabrics_ops nvmet_tcp_ops = {
1833 	.owner			= THIS_MODULE,
1834 	.type			= NVMF_TRTYPE_TCP,
1835 	.msdbd			= 1,
1836 	.add_port		= nvmet_tcp_add_port,
1837 	.remove_port		= nvmet_tcp_remove_port,
1838 	.queue_response		= nvmet_tcp_queue_response,
1839 	.delete_ctrl		= nvmet_tcp_delete_ctrl,
1840 	.install_queue		= nvmet_tcp_install_queue,
1841 	.disc_traddr		= nvmet_tcp_disc_port_addr,
1842 };
1843 
1844 static int __init nvmet_tcp_init(void)
1845 {
1846 	int ret;
1847 
1848 	nvmet_tcp_wq = alloc_workqueue("nvmet_tcp_wq",
1849 				WQ_MEM_RECLAIM | WQ_HIGHPRI, 0);
1850 	if (!nvmet_tcp_wq)
1851 		return -ENOMEM;
1852 
1853 	ret = nvmet_register_transport(&nvmet_tcp_ops);
1854 	if (ret)
1855 		goto err;
1856 
1857 	return 0;
1858 err:
1859 	destroy_workqueue(nvmet_tcp_wq);
1860 	return ret;
1861 }
1862 
1863 static void __exit nvmet_tcp_exit(void)
1864 {
1865 	struct nvmet_tcp_queue *queue;
1866 
1867 	nvmet_unregister_transport(&nvmet_tcp_ops);
1868 
1869 	flush_workqueue(nvmet_wq);
1870 	mutex_lock(&nvmet_tcp_queue_mutex);
1871 	list_for_each_entry(queue, &nvmet_tcp_queue_list, queue_list)
1872 		kernel_sock_shutdown(queue->sock, SHUT_RDWR);
1873 	mutex_unlock(&nvmet_tcp_queue_mutex);
1874 	flush_workqueue(nvmet_wq);
1875 
1876 	destroy_workqueue(nvmet_tcp_wq);
1877 }
1878 
1879 module_init(nvmet_tcp_init);
1880 module_exit(nvmet_tcp_exit);
1881 
1882 MODULE_LICENSE("GPL v2");
1883 MODULE_ALIAS("nvmet-transport-3"); /* 3 == NVMF_TRTYPE_TCP */
1884