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/key.h>
12#include <linux/nvme-tcp.h>
13#include <linux/nvme-keyring.h>
14#include <net/sock.h>
15#include <net/tcp.h>
16#include <net/tls.h>
17#include <net/tls_prot.h>
18#include <net/handshake.h>
19#include <linux/inet.h>
20#include <linux/llist.h>
21#include <crypto/hash.h>
22#include <trace/events/sock.h>
23
24#include "nvmet.h"
25
26#define NVMET_TCP_DEF_INLINE_DATA_SIZE	(4 * PAGE_SIZE)
27#define NVMET_TCP_MAXH2CDATA		0x400000 /* 16M arbitrary limit */
28#define NVMET_TCP_BACKLOG 128
29
30static int param_store_val(const char *str, int *val, int min, int max)
31{
32	int ret, new_val;
33
34	ret = kstrtoint(str, 10, &new_val);
35	if (ret)
36		return -EINVAL;
37
38	if (new_val < min || new_val > max)
39		return -EINVAL;
40
41	*val = new_val;
42	return 0;
43}
44
45static int set_params(const char *str, const struct kernel_param *kp)
46{
47	return param_store_val(str, kp->arg, 0, INT_MAX);
48}
49
50static const struct kernel_param_ops set_param_ops = {
51	.set	= set_params,
52	.get	= param_get_int,
53};
54
55/* Define the socket priority to use for connections were it is desirable
56 * that the NIC consider performing optimized packet processing or filtering.
57 * A non-zero value being sufficient to indicate general consideration of any
58 * possible optimization.  Making it a module param allows for alternative
59 * values that may be unique for some NIC implementations.
60 */
61static int so_priority;
62device_param_cb(so_priority, &set_param_ops, &so_priority, 0644);
63MODULE_PARM_DESC(so_priority, "nvmet tcp socket optimize priority: Default 0");
64
65/* Define a time period (in usecs) that io_work() shall sample an activated
66 * queue before determining it to be idle.  This optional module behavior
67 * can enable NIC solutions that support socket optimized packet processing
68 * using advanced interrupt moderation techniques.
69 */
70static int idle_poll_period_usecs;
71device_param_cb(idle_poll_period_usecs, &set_param_ops,
72		&idle_poll_period_usecs, 0644);
73MODULE_PARM_DESC(idle_poll_period_usecs,
74		"nvmet tcp io_work poll till idle time period in usecs: Default 0");
75
76#ifdef CONFIG_NVME_TARGET_TCP_TLS
77/*
78 * TLS handshake timeout
79 */
80static int tls_handshake_timeout = 10;
81module_param(tls_handshake_timeout, int, 0644);
82MODULE_PARM_DESC(tls_handshake_timeout,
83		 "nvme TLS handshake timeout in seconds (default 10)");
84#endif
85
86#define NVMET_TCP_RECV_BUDGET		8
87#define NVMET_TCP_SEND_BUDGET		8
88#define NVMET_TCP_IO_WORK_BUDGET	64
89
90enum nvmet_tcp_send_state {
91	NVMET_TCP_SEND_DATA_PDU,
92	NVMET_TCP_SEND_DATA,
93	NVMET_TCP_SEND_R2T,
94	NVMET_TCP_SEND_DDGST,
95	NVMET_TCP_SEND_RESPONSE
96};
97
98enum nvmet_tcp_recv_state {
99	NVMET_TCP_RECV_PDU,
100	NVMET_TCP_RECV_DATA,
101	NVMET_TCP_RECV_DDGST,
102	NVMET_TCP_RECV_ERR,
103};
104
105enum {
106	NVMET_TCP_F_INIT_FAILED = (1 << 0),
107};
108
109struct nvmet_tcp_cmd {
110	struct nvmet_tcp_queue		*queue;
111	struct nvmet_req		req;
112
113	struct nvme_tcp_cmd_pdu		*cmd_pdu;
114	struct nvme_tcp_rsp_pdu		*rsp_pdu;
115	struct nvme_tcp_data_pdu	*data_pdu;
116	struct nvme_tcp_r2t_pdu		*r2t_pdu;
117
118	u32				rbytes_done;
119	u32				wbytes_done;
120
121	u32				pdu_len;
122	u32				pdu_recv;
123	int				sg_idx;
124	char				recv_cbuf[CMSG_LEN(sizeof(char))];
125	struct msghdr			recv_msg;
126	struct bio_vec			*iov;
127	u32				flags;
128
129	struct list_head		entry;
130	struct llist_node		lentry;
131
132	/* send state */
133	u32				offset;
134	struct scatterlist		*cur_sg;
135	enum nvmet_tcp_send_state	state;
136
137	__le32				exp_ddgst;
138	__le32				recv_ddgst;
139};
140
141enum nvmet_tcp_queue_state {
142	NVMET_TCP_Q_CONNECTING,
143	NVMET_TCP_Q_TLS_HANDSHAKE,
144	NVMET_TCP_Q_LIVE,
145	NVMET_TCP_Q_DISCONNECTING,
146	NVMET_TCP_Q_FAILED,
147};
148
149struct nvmet_tcp_queue {
150	struct socket		*sock;
151	struct nvmet_tcp_port	*port;
152	struct work_struct	io_work;
153	struct nvmet_cq		nvme_cq;
154	struct nvmet_sq		nvme_sq;
155	struct kref		kref;
156
157	/* send state */
158	struct nvmet_tcp_cmd	*cmds;
159	unsigned int		nr_cmds;
160	struct list_head	free_list;
161	struct llist_head	resp_list;
162	struct list_head	resp_send_list;
163	int			send_list_len;
164	struct nvmet_tcp_cmd	*snd_cmd;
165
166	/* recv state */
167	int			offset;
168	int			left;
169	enum nvmet_tcp_recv_state rcv_state;
170	struct nvmet_tcp_cmd	*cmd;
171	union nvme_tcp_pdu	pdu;
172
173	/* digest state */
174	bool			hdr_digest;
175	bool			data_digest;
176	struct ahash_request	*snd_hash;
177	struct ahash_request	*rcv_hash;
178
179	/* TLS state */
180	key_serial_t		tls_pskid;
181	struct delayed_work	tls_handshake_tmo_work;
182
183	unsigned long           poll_end;
184
185	spinlock_t		state_lock;
186	enum nvmet_tcp_queue_state state;
187
188	struct sockaddr_storage	sockaddr;
189	struct sockaddr_storage	sockaddr_peer;
190	struct work_struct	release_work;
191
192	int			idx;
193	struct list_head	queue_list;
194
195	struct nvmet_tcp_cmd	connect;
196
197	struct page_frag_cache	pf_cache;
198
199	void (*data_ready)(struct sock *);
200	void (*state_change)(struct sock *);
201	void (*write_space)(struct sock *);
202};
203
204struct nvmet_tcp_port {
205	struct socket		*sock;
206	struct work_struct	accept_work;
207	struct nvmet_port	*nport;
208	struct sockaddr_storage addr;
209	void (*data_ready)(struct sock *);
210};
211
212static DEFINE_IDA(nvmet_tcp_queue_ida);
213static LIST_HEAD(nvmet_tcp_queue_list);
214static DEFINE_MUTEX(nvmet_tcp_queue_mutex);
215
216static struct workqueue_struct *nvmet_tcp_wq;
217static const struct nvmet_fabrics_ops nvmet_tcp_ops;
218static void nvmet_tcp_free_cmd(struct nvmet_tcp_cmd *c);
219static void nvmet_tcp_free_cmd_buffers(struct nvmet_tcp_cmd *cmd);
220
221static inline u16 nvmet_tcp_cmd_tag(struct nvmet_tcp_queue *queue,
222		struct nvmet_tcp_cmd *cmd)
223{
224	if (unlikely(!queue->nr_cmds)) {
225		/* We didn't allocate cmds yet, send 0xffff */
226		return USHRT_MAX;
227	}
228
229	return cmd - queue->cmds;
230}
231
232static inline bool nvmet_tcp_has_data_in(struct nvmet_tcp_cmd *cmd)
233{
234	return nvme_is_write(cmd->req.cmd) &&
235		cmd->rbytes_done < cmd->req.transfer_len;
236}
237
238static inline bool nvmet_tcp_need_data_in(struct nvmet_tcp_cmd *cmd)
239{
240	return nvmet_tcp_has_data_in(cmd) && !cmd->req.cqe->status;
241}
242
243static inline bool nvmet_tcp_need_data_out(struct nvmet_tcp_cmd *cmd)
244{
245	return !nvme_is_write(cmd->req.cmd) &&
246		cmd->req.transfer_len > 0 &&
247		!cmd->req.cqe->status;
248}
249
250static inline bool nvmet_tcp_has_inline_data(struct nvmet_tcp_cmd *cmd)
251{
252	return nvme_is_write(cmd->req.cmd) && cmd->pdu_len &&
253		!cmd->rbytes_done;
254}
255
256static inline struct nvmet_tcp_cmd *
257nvmet_tcp_get_cmd(struct nvmet_tcp_queue *queue)
258{
259	struct nvmet_tcp_cmd *cmd;
260
261	cmd = list_first_entry_or_null(&queue->free_list,
262				struct nvmet_tcp_cmd, entry);
263	if (!cmd)
264		return NULL;
265	list_del_init(&cmd->entry);
266
267	cmd->rbytes_done = cmd->wbytes_done = 0;
268	cmd->pdu_len = 0;
269	cmd->pdu_recv = 0;
270	cmd->iov = NULL;
271	cmd->flags = 0;
272	return cmd;
273}
274
275static inline void nvmet_tcp_put_cmd(struct nvmet_tcp_cmd *cmd)
276{
277	if (unlikely(cmd == &cmd->queue->connect))
278		return;
279
280	list_add_tail(&cmd->entry, &cmd->queue->free_list);
281}
282
283static inline int queue_cpu(struct nvmet_tcp_queue *queue)
284{
285	return queue->sock->sk->sk_incoming_cpu;
286}
287
288static inline u8 nvmet_tcp_hdgst_len(struct nvmet_tcp_queue *queue)
289{
290	return queue->hdr_digest ? NVME_TCP_DIGEST_LENGTH : 0;
291}
292
293static inline u8 nvmet_tcp_ddgst_len(struct nvmet_tcp_queue *queue)
294{
295	return queue->data_digest ? NVME_TCP_DIGEST_LENGTH : 0;
296}
297
298static inline void nvmet_tcp_hdgst(struct ahash_request *hash,
299		void *pdu, size_t len)
300{
301	struct scatterlist sg;
302
303	sg_init_one(&sg, pdu, len);
304	ahash_request_set_crypt(hash, &sg, pdu + len, len);
305	crypto_ahash_digest(hash);
306}
307
308static int nvmet_tcp_verify_hdgst(struct nvmet_tcp_queue *queue,
309	void *pdu, size_t len)
310{
311	struct nvme_tcp_hdr *hdr = pdu;
312	__le32 recv_digest;
313	__le32 exp_digest;
314
315	if (unlikely(!(hdr->flags & NVME_TCP_F_HDGST))) {
316		pr_err("queue %d: header digest enabled but no header digest\n",
317			queue->idx);
318		return -EPROTO;
319	}
320
321	recv_digest = *(__le32 *)(pdu + hdr->hlen);
322	nvmet_tcp_hdgst(queue->rcv_hash, pdu, len);
323	exp_digest = *(__le32 *)(pdu + hdr->hlen);
324	if (recv_digest != exp_digest) {
325		pr_err("queue %d: header digest error: recv %#x expected %#x\n",
326			queue->idx, le32_to_cpu(recv_digest),
327			le32_to_cpu(exp_digest));
328		return -EPROTO;
329	}
330
331	return 0;
332}
333
334static int nvmet_tcp_check_ddgst(struct nvmet_tcp_queue *queue, void *pdu)
335{
336	struct nvme_tcp_hdr *hdr = pdu;
337	u8 digest_len = nvmet_tcp_hdgst_len(queue);
338	u32 len;
339
340	len = le32_to_cpu(hdr->plen) - hdr->hlen -
341		(hdr->flags & NVME_TCP_F_HDGST ? digest_len : 0);
342
343	if (unlikely(len && !(hdr->flags & NVME_TCP_F_DDGST))) {
344		pr_err("queue %d: data digest flag is cleared\n", queue->idx);
345		return -EPROTO;
346	}
347
348	return 0;
349}
350
351static void nvmet_tcp_free_cmd_buffers(struct nvmet_tcp_cmd *cmd)
352{
353	kfree(cmd->iov);
354	sgl_free(cmd->req.sg);
355	cmd->iov = NULL;
356	cmd->req.sg = NULL;
357}
358
359static void nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd)
360{
361	struct bio_vec *iov = cmd->iov;
362	struct scatterlist *sg;
363	u32 length, offset, sg_offset;
364	int nr_pages;
365
366	length = cmd->pdu_len;
367	nr_pages = DIV_ROUND_UP(length, PAGE_SIZE);
368	offset = cmd->rbytes_done;
369	cmd->sg_idx = offset / PAGE_SIZE;
370	sg_offset = offset % PAGE_SIZE;
371	sg = &cmd->req.sg[cmd->sg_idx];
372
373	while (length) {
374		u32 iov_len = min_t(u32, length, sg->length - sg_offset);
375
376		bvec_set_page(iov, sg_page(sg), iov_len,
377				sg->offset + sg_offset);
378
379		length -= iov_len;
380		sg = sg_next(sg);
381		iov++;
382		sg_offset = 0;
383	}
384
385	iov_iter_bvec(&cmd->recv_msg.msg_iter, ITER_DEST, cmd->iov,
386		      nr_pages, cmd->pdu_len);
387}
388
389static void nvmet_tcp_fatal_error(struct nvmet_tcp_queue *queue)
390{
391	queue->rcv_state = NVMET_TCP_RECV_ERR;
392	if (queue->nvme_sq.ctrl)
393		nvmet_ctrl_fatal_error(queue->nvme_sq.ctrl);
394	else
395		kernel_sock_shutdown(queue->sock, SHUT_RDWR);
396}
397
398static void nvmet_tcp_socket_error(struct nvmet_tcp_queue *queue, int status)
399{
400	queue->rcv_state = NVMET_TCP_RECV_ERR;
401	if (status == -EPIPE || status == -ECONNRESET)
402		kernel_sock_shutdown(queue->sock, SHUT_RDWR);
403	else
404		nvmet_tcp_fatal_error(queue);
405}
406
407static int nvmet_tcp_map_data(struct nvmet_tcp_cmd *cmd)
408{
409	struct nvme_sgl_desc *sgl = &cmd->req.cmd->common.dptr.sgl;
410	u32 len = le32_to_cpu(sgl->length);
411
412	if (!len)
413		return 0;
414
415	if (sgl->type == ((NVME_SGL_FMT_DATA_DESC << 4) |
416			  NVME_SGL_FMT_OFFSET)) {
417		if (!nvme_is_write(cmd->req.cmd))
418			return NVME_SC_INVALID_FIELD | NVME_SC_DNR;
419
420		if (len > cmd->req.port->inline_data_size)
421			return NVME_SC_SGL_INVALID_OFFSET | NVME_SC_DNR;
422		cmd->pdu_len = len;
423	}
424	cmd->req.transfer_len += len;
425
426	cmd->req.sg = sgl_alloc(len, GFP_KERNEL, &cmd->req.sg_cnt);
427	if (!cmd->req.sg)
428		return NVME_SC_INTERNAL;
429	cmd->cur_sg = cmd->req.sg;
430
431	if (nvmet_tcp_has_data_in(cmd)) {
432		cmd->iov = kmalloc_array(cmd->req.sg_cnt,
433				sizeof(*cmd->iov), GFP_KERNEL);
434		if (!cmd->iov)
435			goto err;
436	}
437
438	return 0;
439err:
440	nvmet_tcp_free_cmd_buffers(cmd);
441	return NVME_SC_INTERNAL;
442}
443
444static void nvmet_tcp_calc_ddgst(struct ahash_request *hash,
445		struct nvmet_tcp_cmd *cmd)
446{
447	ahash_request_set_crypt(hash, cmd->req.sg,
448		(void *)&cmd->exp_ddgst, cmd->req.transfer_len);
449	crypto_ahash_digest(hash);
450}
451
452static void nvmet_setup_c2h_data_pdu(struct nvmet_tcp_cmd *cmd)
453{
454	struct nvme_tcp_data_pdu *pdu = cmd->data_pdu;
455	struct nvmet_tcp_queue *queue = cmd->queue;
456	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
457	u8 ddgst = nvmet_tcp_ddgst_len(cmd->queue);
458
459	cmd->offset = 0;
460	cmd->state = NVMET_TCP_SEND_DATA_PDU;
461
462	pdu->hdr.type = nvme_tcp_c2h_data;
463	pdu->hdr.flags = NVME_TCP_F_DATA_LAST | (queue->nvme_sq.sqhd_disabled ?
464						NVME_TCP_F_DATA_SUCCESS : 0);
465	pdu->hdr.hlen = sizeof(*pdu);
466	pdu->hdr.pdo = pdu->hdr.hlen + hdgst;
467	pdu->hdr.plen =
468		cpu_to_le32(pdu->hdr.hlen + hdgst +
469				cmd->req.transfer_len + ddgst);
470	pdu->command_id = cmd->req.cqe->command_id;
471	pdu->data_length = cpu_to_le32(cmd->req.transfer_len);
472	pdu->data_offset = cpu_to_le32(cmd->wbytes_done);
473
474	if (queue->data_digest) {
475		pdu->hdr.flags |= NVME_TCP_F_DDGST;
476		nvmet_tcp_calc_ddgst(queue->snd_hash, cmd);
477	}
478
479	if (cmd->queue->hdr_digest) {
480		pdu->hdr.flags |= NVME_TCP_F_HDGST;
481		nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu));
482	}
483}
484
485static void nvmet_setup_r2t_pdu(struct nvmet_tcp_cmd *cmd)
486{
487	struct nvme_tcp_r2t_pdu *pdu = cmd->r2t_pdu;
488	struct nvmet_tcp_queue *queue = cmd->queue;
489	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
490
491	cmd->offset = 0;
492	cmd->state = NVMET_TCP_SEND_R2T;
493
494	pdu->hdr.type = nvme_tcp_r2t;
495	pdu->hdr.flags = 0;
496	pdu->hdr.hlen = sizeof(*pdu);
497	pdu->hdr.pdo = 0;
498	pdu->hdr.plen = cpu_to_le32(pdu->hdr.hlen + hdgst);
499
500	pdu->command_id = cmd->req.cmd->common.command_id;
501	pdu->ttag = nvmet_tcp_cmd_tag(cmd->queue, cmd);
502	pdu->r2t_length = cpu_to_le32(cmd->req.transfer_len - cmd->rbytes_done);
503	pdu->r2t_offset = cpu_to_le32(cmd->rbytes_done);
504	if (cmd->queue->hdr_digest) {
505		pdu->hdr.flags |= NVME_TCP_F_HDGST;
506		nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu));
507	}
508}
509
510static void nvmet_setup_response_pdu(struct nvmet_tcp_cmd *cmd)
511{
512	struct nvme_tcp_rsp_pdu *pdu = cmd->rsp_pdu;
513	struct nvmet_tcp_queue *queue = cmd->queue;
514	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
515
516	cmd->offset = 0;
517	cmd->state = NVMET_TCP_SEND_RESPONSE;
518
519	pdu->hdr.type = nvme_tcp_rsp;
520	pdu->hdr.flags = 0;
521	pdu->hdr.hlen = sizeof(*pdu);
522	pdu->hdr.pdo = 0;
523	pdu->hdr.plen = cpu_to_le32(pdu->hdr.hlen + hdgst);
524	if (cmd->queue->hdr_digest) {
525		pdu->hdr.flags |= NVME_TCP_F_HDGST;
526		nvmet_tcp_hdgst(queue->snd_hash, pdu, sizeof(*pdu));
527	}
528}
529
530static void nvmet_tcp_process_resp_list(struct nvmet_tcp_queue *queue)
531{
532	struct llist_node *node;
533	struct nvmet_tcp_cmd *cmd;
534
535	for (node = llist_del_all(&queue->resp_list); node; node = node->next) {
536		cmd = llist_entry(node, struct nvmet_tcp_cmd, lentry);
537		list_add(&cmd->entry, &queue->resp_send_list);
538		queue->send_list_len++;
539	}
540}
541
542static struct nvmet_tcp_cmd *nvmet_tcp_fetch_cmd(struct nvmet_tcp_queue *queue)
543{
544	queue->snd_cmd = list_first_entry_or_null(&queue->resp_send_list,
545				struct nvmet_tcp_cmd, entry);
546	if (!queue->snd_cmd) {
547		nvmet_tcp_process_resp_list(queue);
548		queue->snd_cmd =
549			list_first_entry_or_null(&queue->resp_send_list,
550					struct nvmet_tcp_cmd, entry);
551		if (unlikely(!queue->snd_cmd))
552			return NULL;
553	}
554
555	list_del_init(&queue->snd_cmd->entry);
556	queue->send_list_len--;
557
558	if (nvmet_tcp_need_data_out(queue->snd_cmd))
559		nvmet_setup_c2h_data_pdu(queue->snd_cmd);
560	else if (nvmet_tcp_need_data_in(queue->snd_cmd))
561		nvmet_setup_r2t_pdu(queue->snd_cmd);
562	else
563		nvmet_setup_response_pdu(queue->snd_cmd);
564
565	return queue->snd_cmd;
566}
567
568static void nvmet_tcp_queue_response(struct nvmet_req *req)
569{
570	struct nvmet_tcp_cmd *cmd =
571		container_of(req, struct nvmet_tcp_cmd, req);
572	struct nvmet_tcp_queue	*queue = cmd->queue;
573	struct nvme_sgl_desc *sgl;
574	u32 len;
575
576	if (unlikely(cmd == queue->cmd)) {
577		sgl = &cmd->req.cmd->common.dptr.sgl;
578		len = le32_to_cpu(sgl->length);
579
580		/*
581		 * Wait for inline data before processing the response.
582		 * Avoid using helpers, this might happen before
583		 * nvmet_req_init is completed.
584		 */
585		if (queue->rcv_state == NVMET_TCP_RECV_PDU &&
586		    len && len <= cmd->req.port->inline_data_size &&
587		    nvme_is_write(cmd->req.cmd))
588			return;
589	}
590
591	llist_add(&cmd->lentry, &queue->resp_list);
592	queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &cmd->queue->io_work);
593}
594
595static void nvmet_tcp_execute_request(struct nvmet_tcp_cmd *cmd)
596{
597	if (unlikely(cmd->flags & NVMET_TCP_F_INIT_FAILED))
598		nvmet_tcp_queue_response(&cmd->req);
599	else
600		cmd->req.execute(&cmd->req);
601}
602
603static int nvmet_try_send_data_pdu(struct nvmet_tcp_cmd *cmd)
604{
605	struct msghdr msg = {
606		.msg_flags = MSG_DONTWAIT | MSG_MORE | MSG_SPLICE_PAGES,
607	};
608	struct bio_vec bvec;
609	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
610	int left = sizeof(*cmd->data_pdu) - cmd->offset + hdgst;
611	int ret;
612
613	bvec_set_virt(&bvec, (void *)cmd->data_pdu + cmd->offset, left);
614	iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, left);
615	ret = sock_sendmsg(cmd->queue->sock, &msg);
616	if (ret <= 0)
617		return ret;
618
619	cmd->offset += ret;
620	left -= ret;
621
622	if (left)
623		return -EAGAIN;
624
625	cmd->state = NVMET_TCP_SEND_DATA;
626	cmd->offset  = 0;
627	return 1;
628}
629
630static int nvmet_try_send_data(struct nvmet_tcp_cmd *cmd, bool last_in_batch)
631{
632	struct nvmet_tcp_queue *queue = cmd->queue;
633	int ret;
634
635	while (cmd->cur_sg) {
636		struct msghdr msg = {
637			.msg_flags = MSG_DONTWAIT | MSG_SPLICE_PAGES,
638		};
639		struct page *page = sg_page(cmd->cur_sg);
640		struct bio_vec bvec;
641		u32 left = cmd->cur_sg->length - cmd->offset;
642
643		if ((!last_in_batch && cmd->queue->send_list_len) ||
644		    cmd->wbytes_done + left < cmd->req.transfer_len ||
645		    queue->data_digest || !queue->nvme_sq.sqhd_disabled)
646			msg.msg_flags |= MSG_MORE;
647
648		bvec_set_page(&bvec, page, left, cmd->offset);
649		iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, left);
650		ret = sock_sendmsg(cmd->queue->sock, &msg);
651		if (ret <= 0)
652			return ret;
653
654		cmd->offset += ret;
655		cmd->wbytes_done += ret;
656
657		/* Done with sg?*/
658		if (cmd->offset == cmd->cur_sg->length) {
659			cmd->cur_sg = sg_next(cmd->cur_sg);
660			cmd->offset = 0;
661		}
662	}
663
664	if (queue->data_digest) {
665		cmd->state = NVMET_TCP_SEND_DDGST;
666		cmd->offset = 0;
667	} else {
668		if (queue->nvme_sq.sqhd_disabled) {
669			cmd->queue->snd_cmd = NULL;
670			nvmet_tcp_put_cmd(cmd);
671		} else {
672			nvmet_setup_response_pdu(cmd);
673		}
674	}
675
676	if (queue->nvme_sq.sqhd_disabled)
677		nvmet_tcp_free_cmd_buffers(cmd);
678
679	return 1;
680
681}
682
683static int nvmet_try_send_response(struct nvmet_tcp_cmd *cmd,
684		bool last_in_batch)
685{
686	struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_SPLICE_PAGES, };
687	struct bio_vec bvec;
688	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
689	int left = sizeof(*cmd->rsp_pdu) - cmd->offset + hdgst;
690	int ret;
691
692	if (!last_in_batch && cmd->queue->send_list_len)
693		msg.msg_flags |= MSG_MORE;
694	else
695		msg.msg_flags |= MSG_EOR;
696
697	bvec_set_virt(&bvec, (void *)cmd->rsp_pdu + cmd->offset, left);
698	iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, left);
699	ret = sock_sendmsg(cmd->queue->sock, &msg);
700	if (ret <= 0)
701		return ret;
702	cmd->offset += ret;
703	left -= ret;
704
705	if (left)
706		return -EAGAIN;
707
708	nvmet_tcp_free_cmd_buffers(cmd);
709	cmd->queue->snd_cmd = NULL;
710	nvmet_tcp_put_cmd(cmd);
711	return 1;
712}
713
714static int nvmet_try_send_r2t(struct nvmet_tcp_cmd *cmd, bool last_in_batch)
715{
716	struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_SPLICE_PAGES, };
717	struct bio_vec bvec;
718	u8 hdgst = nvmet_tcp_hdgst_len(cmd->queue);
719	int left = sizeof(*cmd->r2t_pdu) - cmd->offset + hdgst;
720	int ret;
721
722	if (!last_in_batch && cmd->queue->send_list_len)
723		msg.msg_flags |= MSG_MORE;
724	else
725		msg.msg_flags |= MSG_EOR;
726
727	bvec_set_virt(&bvec, (void *)cmd->r2t_pdu + cmd->offset, left);
728	iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, left);
729	ret = sock_sendmsg(cmd->queue->sock, &msg);
730	if (ret <= 0)
731		return ret;
732	cmd->offset += ret;
733	left -= ret;
734
735	if (left)
736		return -EAGAIN;
737
738	cmd->queue->snd_cmd = NULL;
739	return 1;
740}
741
742static int nvmet_try_send_ddgst(struct nvmet_tcp_cmd *cmd, bool last_in_batch)
743{
744	struct nvmet_tcp_queue *queue = cmd->queue;
745	int left = NVME_TCP_DIGEST_LENGTH - cmd->offset;
746	struct msghdr msg = { .msg_flags = MSG_DONTWAIT };
747	struct kvec iov = {
748		.iov_base = (u8 *)&cmd->exp_ddgst + cmd->offset,
749		.iov_len = left
750	};
751	int ret;
752
753	if (!last_in_batch && cmd->queue->send_list_len)
754		msg.msg_flags |= MSG_MORE;
755	else
756		msg.msg_flags |= MSG_EOR;
757
758	ret = kernel_sendmsg(queue->sock, &msg, &iov, 1, iov.iov_len);
759	if (unlikely(ret <= 0))
760		return ret;
761
762	cmd->offset += ret;
763	left -= ret;
764
765	if (left)
766		return -EAGAIN;
767
768	if (queue->nvme_sq.sqhd_disabled) {
769		cmd->queue->snd_cmd = NULL;
770		nvmet_tcp_put_cmd(cmd);
771	} else {
772		nvmet_setup_response_pdu(cmd);
773	}
774	return 1;
775}
776
777static int nvmet_tcp_try_send_one(struct nvmet_tcp_queue *queue,
778		bool last_in_batch)
779{
780	struct nvmet_tcp_cmd *cmd = queue->snd_cmd;
781	int ret = 0;
782
783	if (!cmd || queue->state == NVMET_TCP_Q_DISCONNECTING) {
784		cmd = nvmet_tcp_fetch_cmd(queue);
785		if (unlikely(!cmd))
786			return 0;
787	}
788
789	if (cmd->state == NVMET_TCP_SEND_DATA_PDU) {
790		ret = nvmet_try_send_data_pdu(cmd);
791		if (ret <= 0)
792			goto done_send;
793	}
794
795	if (cmd->state == NVMET_TCP_SEND_DATA) {
796		ret = nvmet_try_send_data(cmd, last_in_batch);
797		if (ret <= 0)
798			goto done_send;
799	}
800
801	if (cmd->state == NVMET_TCP_SEND_DDGST) {
802		ret = nvmet_try_send_ddgst(cmd, last_in_batch);
803		if (ret <= 0)
804			goto done_send;
805	}
806
807	if (cmd->state == NVMET_TCP_SEND_R2T) {
808		ret = nvmet_try_send_r2t(cmd, last_in_batch);
809		if (ret <= 0)
810			goto done_send;
811	}
812
813	if (cmd->state == NVMET_TCP_SEND_RESPONSE)
814		ret = nvmet_try_send_response(cmd, last_in_batch);
815
816done_send:
817	if (ret < 0) {
818		if (ret == -EAGAIN)
819			return 0;
820		return ret;
821	}
822
823	return 1;
824}
825
826static int nvmet_tcp_try_send(struct nvmet_tcp_queue *queue,
827		int budget, int *sends)
828{
829	int i, ret = 0;
830
831	for (i = 0; i < budget; i++) {
832		ret = nvmet_tcp_try_send_one(queue, i == budget - 1);
833		if (unlikely(ret < 0)) {
834			nvmet_tcp_socket_error(queue, ret);
835			goto done;
836		} else if (ret == 0) {
837			break;
838		}
839		(*sends)++;
840	}
841done:
842	return ret;
843}
844
845static void nvmet_prepare_receive_pdu(struct nvmet_tcp_queue *queue)
846{
847	queue->offset = 0;
848	queue->left = sizeof(struct nvme_tcp_hdr);
849	queue->cmd = NULL;
850	queue->rcv_state = NVMET_TCP_RECV_PDU;
851}
852
853static void nvmet_tcp_free_crypto(struct nvmet_tcp_queue *queue)
854{
855	struct crypto_ahash *tfm = crypto_ahash_reqtfm(queue->rcv_hash);
856
857	ahash_request_free(queue->rcv_hash);
858	ahash_request_free(queue->snd_hash);
859	crypto_free_ahash(tfm);
860}
861
862static int nvmet_tcp_alloc_crypto(struct nvmet_tcp_queue *queue)
863{
864	struct crypto_ahash *tfm;
865
866	tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC);
867	if (IS_ERR(tfm))
868		return PTR_ERR(tfm);
869
870	queue->snd_hash = ahash_request_alloc(tfm, GFP_KERNEL);
871	if (!queue->snd_hash)
872		goto free_tfm;
873	ahash_request_set_callback(queue->snd_hash, 0, NULL, NULL);
874
875	queue->rcv_hash = ahash_request_alloc(tfm, GFP_KERNEL);
876	if (!queue->rcv_hash)
877		goto free_snd_hash;
878	ahash_request_set_callback(queue->rcv_hash, 0, NULL, NULL);
879
880	return 0;
881free_snd_hash:
882	ahash_request_free(queue->snd_hash);
883free_tfm:
884	crypto_free_ahash(tfm);
885	return -ENOMEM;
886}
887
888
889static int nvmet_tcp_handle_icreq(struct nvmet_tcp_queue *queue)
890{
891	struct nvme_tcp_icreq_pdu *icreq = &queue->pdu.icreq;
892	struct nvme_tcp_icresp_pdu *icresp = &queue->pdu.icresp;
893	struct msghdr msg = {};
894	struct kvec iov;
895	int ret;
896
897	if (le32_to_cpu(icreq->hdr.plen) != sizeof(struct nvme_tcp_icreq_pdu)) {
898		pr_err("bad nvme-tcp pdu length (%d)\n",
899			le32_to_cpu(icreq->hdr.plen));
900		nvmet_tcp_fatal_error(queue);
901		return -EPROTO;
902	}
903
904	if (icreq->pfv != NVME_TCP_PFV_1_0) {
905		pr_err("queue %d: bad pfv %d\n", queue->idx, icreq->pfv);
906		return -EPROTO;
907	}
908
909	if (icreq->hpda != 0) {
910		pr_err("queue %d: unsupported hpda %d\n", queue->idx,
911			icreq->hpda);
912		return -EPROTO;
913	}
914
915	queue->hdr_digest = !!(icreq->digest & NVME_TCP_HDR_DIGEST_ENABLE);
916	queue->data_digest = !!(icreq->digest & NVME_TCP_DATA_DIGEST_ENABLE);
917	if (queue->hdr_digest || queue->data_digest) {
918		ret = nvmet_tcp_alloc_crypto(queue);
919		if (ret)
920			return ret;
921	}
922
923	memset(icresp, 0, sizeof(*icresp));
924	icresp->hdr.type = nvme_tcp_icresp;
925	icresp->hdr.hlen = sizeof(*icresp);
926	icresp->hdr.pdo = 0;
927	icresp->hdr.plen = cpu_to_le32(icresp->hdr.hlen);
928	icresp->pfv = cpu_to_le16(NVME_TCP_PFV_1_0);
929	icresp->maxdata = cpu_to_le32(NVMET_TCP_MAXH2CDATA);
930	icresp->cpda = 0;
931	if (queue->hdr_digest)
932		icresp->digest |= NVME_TCP_HDR_DIGEST_ENABLE;
933	if (queue->data_digest)
934		icresp->digest |= NVME_TCP_DATA_DIGEST_ENABLE;
935
936	iov.iov_base = icresp;
937	iov.iov_len = sizeof(*icresp);
938	ret = kernel_sendmsg(queue->sock, &msg, &iov, 1, iov.iov_len);
939	if (ret < 0) {
940		queue->state = NVMET_TCP_Q_FAILED;
941		return ret; /* queue removal will cleanup */
942	}
943
944	queue->state = NVMET_TCP_Q_LIVE;
945	nvmet_prepare_receive_pdu(queue);
946	return 0;
947}
948
949static void nvmet_tcp_handle_req_failure(struct nvmet_tcp_queue *queue,
950		struct nvmet_tcp_cmd *cmd, struct nvmet_req *req)
951{
952	size_t data_len = le32_to_cpu(req->cmd->common.dptr.sgl.length);
953	int ret;
954
955	/*
956	 * This command has not been processed yet, hence we are trying to
957	 * figure out if there is still pending data left to receive. If
958	 * we don't, we can simply prepare for the next pdu and bail out,
959	 * otherwise we will need to prepare a buffer and receive the
960	 * stale data before continuing forward.
961	 */
962	if (!nvme_is_write(cmd->req.cmd) || !data_len ||
963	    data_len > cmd->req.port->inline_data_size) {
964		nvmet_prepare_receive_pdu(queue);
965		return;
966	}
967
968	ret = nvmet_tcp_map_data(cmd);
969	if (unlikely(ret)) {
970		pr_err("queue %d: failed to map data\n", queue->idx);
971		nvmet_tcp_fatal_error(queue);
972		return;
973	}
974
975	queue->rcv_state = NVMET_TCP_RECV_DATA;
976	nvmet_tcp_build_pdu_iovec(cmd);
977	cmd->flags |= NVMET_TCP_F_INIT_FAILED;
978}
979
980static int nvmet_tcp_handle_h2c_data_pdu(struct nvmet_tcp_queue *queue)
981{
982	struct nvme_tcp_data_pdu *data = &queue->pdu.data;
983	struct nvmet_tcp_cmd *cmd;
984	unsigned int exp_data_len;
985
986	if (likely(queue->nr_cmds)) {
987		if (unlikely(data->ttag >= queue->nr_cmds)) {
988			pr_err("queue %d: received out of bound ttag %u, nr_cmds %u\n",
989				queue->idx, data->ttag, queue->nr_cmds);
990			goto err_proto;
991		}
992		cmd = &queue->cmds[data->ttag];
993	} else {
994		cmd = &queue->connect;
995	}
996
997	if (le32_to_cpu(data->data_offset) != cmd->rbytes_done) {
998		pr_err("ttag %u unexpected data offset %u (expected %u)\n",
999			data->ttag, le32_to_cpu(data->data_offset),
1000			cmd->rbytes_done);
1001		goto err_proto;
1002	}
1003
1004	exp_data_len = le32_to_cpu(data->hdr.plen) -
1005			nvmet_tcp_hdgst_len(queue) -
1006			nvmet_tcp_ddgst_len(queue) -
1007			sizeof(*data);
1008
1009	cmd->pdu_len = le32_to_cpu(data->data_length);
1010	if (unlikely(cmd->pdu_len != exp_data_len ||
1011		     cmd->pdu_len == 0 ||
1012		     cmd->pdu_len > NVMET_TCP_MAXH2CDATA)) {
1013		pr_err("H2CData PDU len %u is invalid\n", cmd->pdu_len);
1014		goto err_proto;
1015	}
1016	cmd->pdu_recv = 0;
1017	nvmet_tcp_build_pdu_iovec(cmd);
1018	queue->cmd = cmd;
1019	queue->rcv_state = NVMET_TCP_RECV_DATA;
1020
1021	return 0;
1022
1023err_proto:
1024	/* FIXME: use proper transport errors */
1025	nvmet_tcp_fatal_error(queue);
1026	return -EPROTO;
1027}
1028
1029static int nvmet_tcp_done_recv_pdu(struct nvmet_tcp_queue *queue)
1030{
1031	struct nvme_tcp_hdr *hdr = &queue->pdu.cmd.hdr;
1032	struct nvme_command *nvme_cmd = &queue->pdu.cmd.cmd;
1033	struct nvmet_req *req;
1034	int ret;
1035
1036	if (unlikely(queue->state == NVMET_TCP_Q_CONNECTING)) {
1037		if (hdr->type != nvme_tcp_icreq) {
1038			pr_err("unexpected pdu type (%d) before icreq\n",
1039				hdr->type);
1040			nvmet_tcp_fatal_error(queue);
1041			return -EPROTO;
1042		}
1043		return nvmet_tcp_handle_icreq(queue);
1044	}
1045
1046	if (unlikely(hdr->type == nvme_tcp_icreq)) {
1047		pr_err("queue %d: received icreq pdu in state %d\n",
1048			queue->idx, queue->state);
1049		nvmet_tcp_fatal_error(queue);
1050		return -EPROTO;
1051	}
1052
1053	if (hdr->type == nvme_tcp_h2c_data) {
1054		ret = nvmet_tcp_handle_h2c_data_pdu(queue);
1055		if (unlikely(ret))
1056			return ret;
1057		return 0;
1058	}
1059
1060	queue->cmd = nvmet_tcp_get_cmd(queue);
1061	if (unlikely(!queue->cmd)) {
1062		/* This should never happen */
1063		pr_err("queue %d: out of commands (%d) send_list_len: %d, opcode: %d",
1064			queue->idx, queue->nr_cmds, queue->send_list_len,
1065			nvme_cmd->common.opcode);
1066		nvmet_tcp_fatal_error(queue);
1067		return -ENOMEM;
1068	}
1069
1070	req = &queue->cmd->req;
1071	memcpy(req->cmd, nvme_cmd, sizeof(*nvme_cmd));
1072
1073	if (unlikely(!nvmet_req_init(req, &queue->nvme_cq,
1074			&queue->nvme_sq, &nvmet_tcp_ops))) {
1075		pr_err("failed cmd %p id %d opcode %d, data_len: %d\n",
1076			req->cmd, req->cmd->common.command_id,
1077			req->cmd->common.opcode,
1078			le32_to_cpu(req->cmd->common.dptr.sgl.length));
1079
1080		nvmet_tcp_handle_req_failure(queue, queue->cmd, req);
1081		return 0;
1082	}
1083
1084	ret = nvmet_tcp_map_data(queue->cmd);
1085	if (unlikely(ret)) {
1086		pr_err("queue %d: failed to map data\n", queue->idx);
1087		if (nvmet_tcp_has_inline_data(queue->cmd))
1088			nvmet_tcp_fatal_error(queue);
1089		else
1090			nvmet_req_complete(req, ret);
1091		ret = -EAGAIN;
1092		goto out;
1093	}
1094
1095	if (nvmet_tcp_need_data_in(queue->cmd)) {
1096		if (nvmet_tcp_has_inline_data(queue->cmd)) {
1097			queue->rcv_state = NVMET_TCP_RECV_DATA;
1098			nvmet_tcp_build_pdu_iovec(queue->cmd);
1099			return 0;
1100		}
1101		/* send back R2T */
1102		nvmet_tcp_queue_response(&queue->cmd->req);
1103		goto out;
1104	}
1105
1106	queue->cmd->req.execute(&queue->cmd->req);
1107out:
1108	nvmet_prepare_receive_pdu(queue);
1109	return ret;
1110}
1111
1112static const u8 nvme_tcp_pdu_sizes[] = {
1113	[nvme_tcp_icreq]	= sizeof(struct nvme_tcp_icreq_pdu),
1114	[nvme_tcp_cmd]		= sizeof(struct nvme_tcp_cmd_pdu),
1115	[nvme_tcp_h2c_data]	= sizeof(struct nvme_tcp_data_pdu),
1116};
1117
1118static inline u8 nvmet_tcp_pdu_size(u8 type)
1119{
1120	size_t idx = type;
1121
1122	return (idx < ARRAY_SIZE(nvme_tcp_pdu_sizes) &&
1123		nvme_tcp_pdu_sizes[idx]) ?
1124			nvme_tcp_pdu_sizes[idx] : 0;
1125}
1126
1127static inline bool nvmet_tcp_pdu_valid(u8 type)
1128{
1129	switch (type) {
1130	case nvme_tcp_icreq:
1131	case nvme_tcp_cmd:
1132	case nvme_tcp_h2c_data:
1133		/* fallthru */
1134		return true;
1135	}
1136
1137	return false;
1138}
1139
1140static int nvmet_tcp_tls_record_ok(struct nvmet_tcp_queue *queue,
1141		struct msghdr *msg, char *cbuf)
1142{
1143	struct cmsghdr *cmsg = (struct cmsghdr *)cbuf;
1144	u8 ctype, level, description;
1145	int ret = 0;
1146
1147	ctype = tls_get_record_type(queue->sock->sk, cmsg);
1148	switch (ctype) {
1149	case 0:
1150		break;
1151	case TLS_RECORD_TYPE_DATA:
1152		break;
1153	case TLS_RECORD_TYPE_ALERT:
1154		tls_alert_recv(queue->sock->sk, msg, &level, &description);
1155		if (level == TLS_ALERT_LEVEL_FATAL) {
1156			pr_err("queue %d: TLS Alert desc %u\n",
1157			       queue->idx, description);
1158			ret = -ENOTCONN;
1159		} else {
1160			pr_warn("queue %d: TLS Alert desc %u\n",
1161			       queue->idx, description);
1162			ret = -EAGAIN;
1163		}
1164		break;
1165	default:
1166		/* discard this record type */
1167		pr_err("queue %d: TLS record %d unhandled\n",
1168		       queue->idx, ctype);
1169		ret = -EAGAIN;
1170		break;
1171	}
1172	return ret;
1173}
1174
1175static int nvmet_tcp_try_recv_pdu(struct nvmet_tcp_queue *queue)
1176{
1177	struct nvme_tcp_hdr *hdr = &queue->pdu.cmd.hdr;
1178	int len, ret;
1179	struct kvec iov;
1180	char cbuf[CMSG_LEN(sizeof(char))] = {};
1181	struct msghdr msg = { .msg_flags = MSG_DONTWAIT };
1182
1183recv:
1184	iov.iov_base = (void *)&queue->pdu + queue->offset;
1185	iov.iov_len = queue->left;
1186	if (queue->tls_pskid) {
1187		msg.msg_control = cbuf;
1188		msg.msg_controllen = sizeof(cbuf);
1189	}
1190	len = kernel_recvmsg(queue->sock, &msg, &iov, 1,
1191			iov.iov_len, msg.msg_flags);
1192	if (unlikely(len < 0))
1193		return len;
1194	if (queue->tls_pskid) {
1195		ret = nvmet_tcp_tls_record_ok(queue, &msg, cbuf);
1196		if (ret < 0)
1197			return ret;
1198	}
1199
1200	queue->offset += len;
1201	queue->left -= len;
1202	if (queue->left)
1203		return -EAGAIN;
1204
1205	if (queue->offset == sizeof(struct nvme_tcp_hdr)) {
1206		u8 hdgst = nvmet_tcp_hdgst_len(queue);
1207
1208		if (unlikely(!nvmet_tcp_pdu_valid(hdr->type))) {
1209			pr_err("unexpected pdu type %d\n", hdr->type);
1210			nvmet_tcp_fatal_error(queue);
1211			return -EIO;
1212		}
1213
1214		if (unlikely(hdr->hlen != nvmet_tcp_pdu_size(hdr->type))) {
1215			pr_err("pdu %d bad hlen %d\n", hdr->type, hdr->hlen);
1216			return -EIO;
1217		}
1218
1219		queue->left = hdr->hlen - queue->offset + hdgst;
1220		goto recv;
1221	}
1222
1223	if (queue->hdr_digest &&
1224	    nvmet_tcp_verify_hdgst(queue, &queue->pdu, hdr->hlen)) {
1225		nvmet_tcp_fatal_error(queue); /* fatal */
1226		return -EPROTO;
1227	}
1228
1229	if (queue->data_digest &&
1230	    nvmet_tcp_check_ddgst(queue, &queue->pdu)) {
1231		nvmet_tcp_fatal_error(queue); /* fatal */
1232		return -EPROTO;
1233	}
1234
1235	return nvmet_tcp_done_recv_pdu(queue);
1236}
1237
1238static void nvmet_tcp_prep_recv_ddgst(struct nvmet_tcp_cmd *cmd)
1239{
1240	struct nvmet_tcp_queue *queue = cmd->queue;
1241
1242	nvmet_tcp_calc_ddgst(queue->rcv_hash, cmd);
1243	queue->offset = 0;
1244	queue->left = NVME_TCP_DIGEST_LENGTH;
1245	queue->rcv_state = NVMET_TCP_RECV_DDGST;
1246}
1247
1248static int nvmet_tcp_try_recv_data(struct nvmet_tcp_queue *queue)
1249{
1250	struct nvmet_tcp_cmd  *cmd = queue->cmd;
1251	int len, ret;
1252
1253	while (msg_data_left(&cmd->recv_msg)) {
1254		len = sock_recvmsg(cmd->queue->sock, &cmd->recv_msg,
1255			cmd->recv_msg.msg_flags);
1256		if (len <= 0)
1257			return len;
1258		if (queue->tls_pskid) {
1259			ret = nvmet_tcp_tls_record_ok(cmd->queue,
1260					&cmd->recv_msg, cmd->recv_cbuf);
1261			if (ret < 0)
1262				return ret;
1263		}
1264
1265		cmd->pdu_recv += len;
1266		cmd->rbytes_done += len;
1267	}
1268
1269	if (queue->data_digest) {
1270		nvmet_tcp_prep_recv_ddgst(cmd);
1271		return 0;
1272	}
1273
1274	if (cmd->rbytes_done == cmd->req.transfer_len)
1275		nvmet_tcp_execute_request(cmd);
1276
1277	nvmet_prepare_receive_pdu(queue);
1278	return 0;
1279}
1280
1281static int nvmet_tcp_try_recv_ddgst(struct nvmet_tcp_queue *queue)
1282{
1283	struct nvmet_tcp_cmd *cmd = queue->cmd;
1284	int ret, len;
1285	char cbuf[CMSG_LEN(sizeof(char))] = {};
1286	struct msghdr msg = { .msg_flags = MSG_DONTWAIT };
1287	struct kvec iov = {
1288		.iov_base = (void *)&cmd->recv_ddgst + queue->offset,
1289		.iov_len = queue->left
1290	};
1291
1292	if (queue->tls_pskid) {
1293		msg.msg_control = cbuf;
1294		msg.msg_controllen = sizeof(cbuf);
1295	}
1296	len = kernel_recvmsg(queue->sock, &msg, &iov, 1,
1297			iov.iov_len, msg.msg_flags);
1298	if (unlikely(len < 0))
1299		return len;
1300	if (queue->tls_pskid) {
1301		ret = nvmet_tcp_tls_record_ok(queue, &msg, cbuf);
1302		if (ret < 0)
1303			return ret;
1304	}
1305
1306	queue->offset += len;
1307	queue->left -= len;
1308	if (queue->left)
1309		return -EAGAIN;
1310
1311	if (queue->data_digest && cmd->exp_ddgst != cmd->recv_ddgst) {
1312		pr_err("queue %d: cmd %d pdu (%d) data digest error: recv %#x expected %#x\n",
1313			queue->idx, cmd->req.cmd->common.command_id,
1314			queue->pdu.cmd.hdr.type, le32_to_cpu(cmd->recv_ddgst),
1315			le32_to_cpu(cmd->exp_ddgst));
1316		nvmet_req_uninit(&cmd->req);
1317		nvmet_tcp_free_cmd_buffers(cmd);
1318		nvmet_tcp_fatal_error(queue);
1319		ret = -EPROTO;
1320		goto out;
1321	}
1322
1323	if (cmd->rbytes_done == cmd->req.transfer_len)
1324		nvmet_tcp_execute_request(cmd);
1325
1326	ret = 0;
1327out:
1328	nvmet_prepare_receive_pdu(queue);
1329	return ret;
1330}
1331
1332static int nvmet_tcp_try_recv_one(struct nvmet_tcp_queue *queue)
1333{
1334	int result = 0;
1335
1336	if (unlikely(queue->rcv_state == NVMET_TCP_RECV_ERR))
1337		return 0;
1338
1339	if (queue->rcv_state == NVMET_TCP_RECV_PDU) {
1340		result = nvmet_tcp_try_recv_pdu(queue);
1341		if (result != 0)
1342			goto done_recv;
1343	}
1344
1345	if (queue->rcv_state == NVMET_TCP_RECV_DATA) {
1346		result = nvmet_tcp_try_recv_data(queue);
1347		if (result != 0)
1348			goto done_recv;
1349	}
1350
1351	if (queue->rcv_state == NVMET_TCP_RECV_DDGST) {
1352		result = nvmet_tcp_try_recv_ddgst(queue);
1353		if (result != 0)
1354			goto done_recv;
1355	}
1356
1357done_recv:
1358	if (result < 0) {
1359		if (result == -EAGAIN)
1360			return 0;
1361		return result;
1362	}
1363	return 1;
1364}
1365
1366static int nvmet_tcp_try_recv(struct nvmet_tcp_queue *queue,
1367		int budget, int *recvs)
1368{
1369	int i, ret = 0;
1370
1371	for (i = 0; i < budget; i++) {
1372		ret = nvmet_tcp_try_recv_one(queue);
1373		if (unlikely(ret < 0)) {
1374			nvmet_tcp_socket_error(queue, ret);
1375			goto done;
1376		} else if (ret == 0) {
1377			break;
1378		}
1379		(*recvs)++;
1380	}
1381done:
1382	return ret;
1383}
1384
1385static void nvmet_tcp_release_queue(struct kref *kref)
1386{
1387	struct nvmet_tcp_queue *queue =
1388		container_of(kref, struct nvmet_tcp_queue, kref);
1389
1390	WARN_ON(queue->state != NVMET_TCP_Q_DISCONNECTING);
1391	queue_work(nvmet_wq, &queue->release_work);
1392}
1393
1394static void nvmet_tcp_schedule_release_queue(struct nvmet_tcp_queue *queue)
1395{
1396	spin_lock_bh(&queue->state_lock);
1397	if (queue->state == NVMET_TCP_Q_TLS_HANDSHAKE) {
1398		/* Socket closed during handshake */
1399		tls_handshake_cancel(queue->sock->sk);
1400	}
1401	if (queue->state != NVMET_TCP_Q_DISCONNECTING) {
1402		queue->state = NVMET_TCP_Q_DISCONNECTING;
1403		kref_put(&queue->kref, nvmet_tcp_release_queue);
1404	}
1405	spin_unlock_bh(&queue->state_lock);
1406}
1407
1408static inline void nvmet_tcp_arm_queue_deadline(struct nvmet_tcp_queue *queue)
1409{
1410	queue->poll_end = jiffies + usecs_to_jiffies(idle_poll_period_usecs);
1411}
1412
1413static bool nvmet_tcp_check_queue_deadline(struct nvmet_tcp_queue *queue,
1414		int ops)
1415{
1416	if (!idle_poll_period_usecs)
1417		return false;
1418
1419	if (ops)
1420		nvmet_tcp_arm_queue_deadline(queue);
1421
1422	return !time_after(jiffies, queue->poll_end);
1423}
1424
1425static void nvmet_tcp_io_work(struct work_struct *w)
1426{
1427	struct nvmet_tcp_queue *queue =
1428		container_of(w, struct nvmet_tcp_queue, io_work);
1429	bool pending;
1430	int ret, ops = 0;
1431
1432	do {
1433		pending = false;
1434
1435		ret = nvmet_tcp_try_recv(queue, NVMET_TCP_RECV_BUDGET, &ops);
1436		if (ret > 0)
1437			pending = true;
1438		else if (ret < 0)
1439			return;
1440
1441		ret = nvmet_tcp_try_send(queue, NVMET_TCP_SEND_BUDGET, &ops);
1442		if (ret > 0)
1443			pending = true;
1444		else if (ret < 0)
1445			return;
1446
1447	} while (pending && ops < NVMET_TCP_IO_WORK_BUDGET);
1448
1449	/*
1450	 * Requeue the worker if idle deadline period is in progress or any
1451	 * ops activity was recorded during the do-while loop above.
1452	 */
1453	if (nvmet_tcp_check_queue_deadline(queue, ops) || pending)
1454		queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work);
1455}
1456
1457static int nvmet_tcp_alloc_cmd(struct nvmet_tcp_queue *queue,
1458		struct nvmet_tcp_cmd *c)
1459{
1460	u8 hdgst = nvmet_tcp_hdgst_len(queue);
1461
1462	c->queue = queue;
1463	c->req.port = queue->port->nport;
1464
1465	c->cmd_pdu = page_frag_alloc(&queue->pf_cache,
1466			sizeof(*c->cmd_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO);
1467	if (!c->cmd_pdu)
1468		return -ENOMEM;
1469	c->req.cmd = &c->cmd_pdu->cmd;
1470
1471	c->rsp_pdu = page_frag_alloc(&queue->pf_cache,
1472			sizeof(*c->rsp_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO);
1473	if (!c->rsp_pdu)
1474		goto out_free_cmd;
1475	c->req.cqe = &c->rsp_pdu->cqe;
1476
1477	c->data_pdu = page_frag_alloc(&queue->pf_cache,
1478			sizeof(*c->data_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO);
1479	if (!c->data_pdu)
1480		goto out_free_rsp;
1481
1482	c->r2t_pdu = page_frag_alloc(&queue->pf_cache,
1483			sizeof(*c->r2t_pdu) + hdgst, GFP_KERNEL | __GFP_ZERO);
1484	if (!c->r2t_pdu)
1485		goto out_free_data;
1486
1487	if (queue->state == NVMET_TCP_Q_TLS_HANDSHAKE) {
1488		c->recv_msg.msg_control = c->recv_cbuf;
1489		c->recv_msg.msg_controllen = sizeof(c->recv_cbuf);
1490	}
1491	c->recv_msg.msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL;
1492
1493	list_add_tail(&c->entry, &queue->free_list);
1494
1495	return 0;
1496out_free_data:
1497	page_frag_free(c->data_pdu);
1498out_free_rsp:
1499	page_frag_free(c->rsp_pdu);
1500out_free_cmd:
1501	page_frag_free(c->cmd_pdu);
1502	return -ENOMEM;
1503}
1504
1505static void nvmet_tcp_free_cmd(struct nvmet_tcp_cmd *c)
1506{
1507	page_frag_free(c->r2t_pdu);
1508	page_frag_free(c->data_pdu);
1509	page_frag_free(c->rsp_pdu);
1510	page_frag_free(c->cmd_pdu);
1511}
1512
1513static int nvmet_tcp_alloc_cmds(struct nvmet_tcp_queue *queue)
1514{
1515	struct nvmet_tcp_cmd *cmds;
1516	int i, ret = -EINVAL, nr_cmds = queue->nr_cmds;
1517
1518	cmds = kcalloc(nr_cmds, sizeof(struct nvmet_tcp_cmd), GFP_KERNEL);
1519	if (!cmds)
1520		goto out;
1521
1522	for (i = 0; i < nr_cmds; i++) {
1523		ret = nvmet_tcp_alloc_cmd(queue, cmds + i);
1524		if (ret)
1525			goto out_free;
1526	}
1527
1528	queue->cmds = cmds;
1529
1530	return 0;
1531out_free:
1532	while (--i >= 0)
1533		nvmet_tcp_free_cmd(cmds + i);
1534	kfree(cmds);
1535out:
1536	return ret;
1537}
1538
1539static void nvmet_tcp_free_cmds(struct nvmet_tcp_queue *queue)
1540{
1541	struct nvmet_tcp_cmd *cmds = queue->cmds;
1542	int i;
1543
1544	for (i = 0; i < queue->nr_cmds; i++)
1545		nvmet_tcp_free_cmd(cmds + i);
1546
1547	nvmet_tcp_free_cmd(&queue->connect);
1548	kfree(cmds);
1549}
1550
1551static void nvmet_tcp_restore_socket_callbacks(struct nvmet_tcp_queue *queue)
1552{
1553	struct socket *sock = queue->sock;
1554
1555	write_lock_bh(&sock->sk->sk_callback_lock);
1556	sock->sk->sk_data_ready =  queue->data_ready;
1557	sock->sk->sk_state_change = queue->state_change;
1558	sock->sk->sk_write_space = queue->write_space;
1559	sock->sk->sk_user_data = NULL;
1560	write_unlock_bh(&sock->sk->sk_callback_lock);
1561}
1562
1563static void nvmet_tcp_uninit_data_in_cmds(struct nvmet_tcp_queue *queue)
1564{
1565	struct nvmet_tcp_cmd *cmd = queue->cmds;
1566	int i;
1567
1568	for (i = 0; i < queue->nr_cmds; i++, cmd++) {
1569		if (nvmet_tcp_need_data_in(cmd))
1570			nvmet_req_uninit(&cmd->req);
1571	}
1572
1573	if (!queue->nr_cmds && nvmet_tcp_need_data_in(&queue->connect)) {
1574		/* failed in connect */
1575		nvmet_req_uninit(&queue->connect.req);
1576	}
1577}
1578
1579static void nvmet_tcp_free_cmd_data_in_buffers(struct nvmet_tcp_queue *queue)
1580{
1581	struct nvmet_tcp_cmd *cmd = queue->cmds;
1582	int i;
1583
1584	for (i = 0; i < queue->nr_cmds; i++, cmd++) {
1585		if (nvmet_tcp_need_data_in(cmd))
1586			nvmet_tcp_free_cmd_buffers(cmd);
1587	}
1588
1589	if (!queue->nr_cmds && nvmet_tcp_need_data_in(&queue->connect))
1590		nvmet_tcp_free_cmd_buffers(&queue->connect);
1591}
1592
1593static void nvmet_tcp_release_queue_work(struct work_struct *w)
1594{
1595	struct nvmet_tcp_queue *queue =
1596		container_of(w, struct nvmet_tcp_queue, release_work);
1597
1598	mutex_lock(&nvmet_tcp_queue_mutex);
1599	list_del_init(&queue->queue_list);
1600	mutex_unlock(&nvmet_tcp_queue_mutex);
1601
1602	nvmet_tcp_restore_socket_callbacks(queue);
1603	cancel_delayed_work_sync(&queue->tls_handshake_tmo_work);
1604	cancel_work_sync(&queue->io_work);
1605	/* stop accepting incoming data */
1606	queue->rcv_state = NVMET_TCP_RECV_ERR;
1607
1608	nvmet_tcp_uninit_data_in_cmds(queue);
1609	nvmet_sq_destroy(&queue->nvme_sq);
1610	cancel_work_sync(&queue->io_work);
1611	nvmet_tcp_free_cmd_data_in_buffers(queue);
1612	/* ->sock will be released by fput() */
1613	fput(queue->sock->file);
1614	nvmet_tcp_free_cmds(queue);
1615	if (queue->hdr_digest || queue->data_digest)
1616		nvmet_tcp_free_crypto(queue);
1617	ida_free(&nvmet_tcp_queue_ida, queue->idx);
1618	page_frag_cache_drain(&queue->pf_cache);
1619	kfree(queue);
1620}
1621
1622static void nvmet_tcp_data_ready(struct sock *sk)
1623{
1624	struct nvmet_tcp_queue *queue;
1625
1626	trace_sk_data_ready(sk);
1627
1628	read_lock_bh(&sk->sk_callback_lock);
1629	queue = sk->sk_user_data;
1630	if (likely(queue)) {
1631		if (queue->data_ready)
1632			queue->data_ready(sk);
1633		if (queue->state != NVMET_TCP_Q_TLS_HANDSHAKE)
1634			queue_work_on(queue_cpu(queue), nvmet_tcp_wq,
1635				      &queue->io_work);
1636	}
1637	read_unlock_bh(&sk->sk_callback_lock);
1638}
1639
1640static void nvmet_tcp_write_space(struct sock *sk)
1641{
1642	struct nvmet_tcp_queue *queue;
1643
1644	read_lock_bh(&sk->sk_callback_lock);
1645	queue = sk->sk_user_data;
1646	if (unlikely(!queue))
1647		goto out;
1648
1649	if (unlikely(queue->state == NVMET_TCP_Q_CONNECTING)) {
1650		queue->write_space(sk);
1651		goto out;
1652	}
1653
1654	if (sk_stream_is_writeable(sk)) {
1655		clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1656		queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work);
1657	}
1658out:
1659	read_unlock_bh(&sk->sk_callback_lock);
1660}
1661
1662static void nvmet_tcp_state_change(struct sock *sk)
1663{
1664	struct nvmet_tcp_queue *queue;
1665
1666	read_lock_bh(&sk->sk_callback_lock);
1667	queue = sk->sk_user_data;
1668	if (!queue)
1669		goto done;
1670
1671	switch (sk->sk_state) {
1672	case TCP_FIN_WAIT2:
1673	case TCP_LAST_ACK:
1674		break;
1675	case TCP_FIN_WAIT1:
1676	case TCP_CLOSE_WAIT:
1677	case TCP_CLOSE:
1678		/* FALLTHRU */
1679		nvmet_tcp_schedule_release_queue(queue);
1680		break;
1681	default:
1682		pr_warn("queue %d unhandled state %d\n",
1683			queue->idx, sk->sk_state);
1684	}
1685done:
1686	read_unlock_bh(&sk->sk_callback_lock);
1687}
1688
1689static int nvmet_tcp_set_queue_sock(struct nvmet_tcp_queue *queue)
1690{
1691	struct socket *sock = queue->sock;
1692	struct inet_sock *inet = inet_sk(sock->sk);
1693	int ret;
1694
1695	ret = kernel_getsockname(sock,
1696		(struct sockaddr *)&queue->sockaddr);
1697	if (ret < 0)
1698		return ret;
1699
1700	ret = kernel_getpeername(sock,
1701		(struct sockaddr *)&queue->sockaddr_peer);
1702	if (ret < 0)
1703		return ret;
1704
1705	/*
1706	 * Cleanup whatever is sitting in the TCP transmit queue on socket
1707	 * close. This is done to prevent stale data from being sent should
1708	 * the network connection be restored before TCP times out.
1709	 */
1710	sock_no_linger(sock->sk);
1711
1712	if (so_priority > 0)
1713		sock_set_priority(sock->sk, so_priority);
1714
1715	/* Set socket type of service */
1716	if (inet->rcv_tos > 0)
1717		ip_sock_set_tos(sock->sk, inet->rcv_tos);
1718
1719	ret = 0;
1720	write_lock_bh(&sock->sk->sk_callback_lock);
1721	if (sock->sk->sk_state != TCP_ESTABLISHED) {
1722		/*
1723		 * If the socket is already closing, don't even start
1724		 * consuming it
1725		 */
1726		ret = -ENOTCONN;
1727	} else {
1728		sock->sk->sk_user_data = queue;
1729		queue->data_ready = sock->sk->sk_data_ready;
1730		sock->sk->sk_data_ready = nvmet_tcp_data_ready;
1731		queue->state_change = sock->sk->sk_state_change;
1732		sock->sk->sk_state_change = nvmet_tcp_state_change;
1733		queue->write_space = sock->sk->sk_write_space;
1734		sock->sk->sk_write_space = nvmet_tcp_write_space;
1735		if (idle_poll_period_usecs)
1736			nvmet_tcp_arm_queue_deadline(queue);
1737		queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work);
1738	}
1739	write_unlock_bh(&sock->sk->sk_callback_lock);
1740
1741	return ret;
1742}
1743
1744#ifdef CONFIG_NVME_TARGET_TCP_TLS
1745static int nvmet_tcp_try_peek_pdu(struct nvmet_tcp_queue *queue)
1746{
1747	struct nvme_tcp_hdr *hdr = &queue->pdu.cmd.hdr;
1748	int len, ret;
1749	struct kvec iov = {
1750		.iov_base = (u8 *)&queue->pdu + queue->offset,
1751		.iov_len = sizeof(struct nvme_tcp_hdr),
1752	};
1753	char cbuf[CMSG_LEN(sizeof(char))] = {};
1754	struct msghdr msg = {
1755		.msg_control = cbuf,
1756		.msg_controllen = sizeof(cbuf),
1757		.msg_flags = MSG_PEEK,
1758	};
1759
1760	if (nvmet_port_secure_channel_required(queue->port->nport))
1761		return 0;
1762
1763	len = kernel_recvmsg(queue->sock, &msg, &iov, 1,
1764			iov.iov_len, msg.msg_flags);
1765	if (unlikely(len < 0)) {
1766		pr_debug("queue %d: peek error %d\n",
1767			 queue->idx, len);
1768		return len;
1769	}
1770
1771	ret = nvmet_tcp_tls_record_ok(queue, &msg, cbuf);
1772	if (ret < 0)
1773		return ret;
1774
1775	if (len < sizeof(struct nvme_tcp_hdr)) {
1776		pr_debug("queue %d: short read, %d bytes missing\n",
1777			 queue->idx, (int)iov.iov_len - len);
1778		return -EAGAIN;
1779	}
1780	pr_debug("queue %d: hdr type %d hlen %d plen %d size %d\n",
1781		 queue->idx, hdr->type, hdr->hlen, hdr->plen,
1782		 (int)sizeof(struct nvme_tcp_icreq_pdu));
1783	if (hdr->type == nvme_tcp_icreq &&
1784	    hdr->hlen == sizeof(struct nvme_tcp_icreq_pdu) &&
1785	    hdr->plen == cpu_to_le32(sizeof(struct nvme_tcp_icreq_pdu))) {
1786		pr_debug("queue %d: icreq detected\n",
1787			 queue->idx);
1788		return len;
1789	}
1790	return 0;
1791}
1792
1793static void nvmet_tcp_tls_handshake_done(void *data, int status,
1794					 key_serial_t peerid)
1795{
1796	struct nvmet_tcp_queue *queue = data;
1797
1798	pr_debug("queue %d: TLS handshake done, key %x, status %d\n",
1799		 queue->idx, peerid, status);
1800	spin_lock_bh(&queue->state_lock);
1801	if (WARN_ON(queue->state != NVMET_TCP_Q_TLS_HANDSHAKE)) {
1802		spin_unlock_bh(&queue->state_lock);
1803		return;
1804	}
1805	if (!status) {
1806		queue->tls_pskid = peerid;
1807		queue->state = NVMET_TCP_Q_CONNECTING;
1808	} else
1809		queue->state = NVMET_TCP_Q_FAILED;
1810	spin_unlock_bh(&queue->state_lock);
1811
1812	cancel_delayed_work_sync(&queue->tls_handshake_tmo_work);
1813	if (status)
1814		nvmet_tcp_schedule_release_queue(queue);
1815	else
1816		nvmet_tcp_set_queue_sock(queue);
1817	kref_put(&queue->kref, nvmet_tcp_release_queue);
1818}
1819
1820static void nvmet_tcp_tls_handshake_timeout(struct work_struct *w)
1821{
1822	struct nvmet_tcp_queue *queue = container_of(to_delayed_work(w),
1823			struct nvmet_tcp_queue, tls_handshake_tmo_work);
1824
1825	pr_warn("queue %d: TLS handshake timeout\n", queue->idx);
1826	/*
1827	 * If tls_handshake_cancel() fails we've lost the race with
1828	 * nvmet_tcp_tls_handshake_done() */
1829	if (!tls_handshake_cancel(queue->sock->sk))
1830		return;
1831	spin_lock_bh(&queue->state_lock);
1832	if (WARN_ON(queue->state != NVMET_TCP_Q_TLS_HANDSHAKE)) {
1833		spin_unlock_bh(&queue->state_lock);
1834		return;
1835	}
1836	queue->state = NVMET_TCP_Q_FAILED;
1837	spin_unlock_bh(&queue->state_lock);
1838	nvmet_tcp_schedule_release_queue(queue);
1839	kref_put(&queue->kref, nvmet_tcp_release_queue);
1840}
1841
1842static int nvmet_tcp_tls_handshake(struct nvmet_tcp_queue *queue)
1843{
1844	int ret = -EOPNOTSUPP;
1845	struct tls_handshake_args args;
1846
1847	if (queue->state != NVMET_TCP_Q_TLS_HANDSHAKE) {
1848		pr_warn("cannot start TLS in state %d\n", queue->state);
1849		return -EINVAL;
1850	}
1851
1852	kref_get(&queue->kref);
1853	pr_debug("queue %d: TLS ServerHello\n", queue->idx);
1854	memset(&args, 0, sizeof(args));
1855	args.ta_sock = queue->sock;
1856	args.ta_done = nvmet_tcp_tls_handshake_done;
1857	args.ta_data = queue;
1858	args.ta_keyring = key_serial(queue->port->nport->keyring);
1859	args.ta_timeout_ms = tls_handshake_timeout * 1000;
1860
1861	ret = tls_server_hello_psk(&args, GFP_KERNEL);
1862	if (ret) {
1863		kref_put(&queue->kref, nvmet_tcp_release_queue);
1864		pr_err("failed to start TLS, err=%d\n", ret);
1865	} else {
1866		queue_delayed_work(nvmet_wq, &queue->tls_handshake_tmo_work,
1867				   tls_handshake_timeout * HZ);
1868	}
1869	return ret;
1870}
1871#else
1872static void nvmet_tcp_tls_handshake_timeout(struct work_struct *w) {}
1873#endif
1874
1875static void nvmet_tcp_alloc_queue(struct nvmet_tcp_port *port,
1876		struct socket *newsock)
1877{
1878	struct nvmet_tcp_queue *queue;
1879	struct file *sock_file = NULL;
1880	int ret;
1881
1882	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
1883	if (!queue) {
1884		ret = -ENOMEM;
1885		goto out_release;
1886	}
1887
1888	INIT_WORK(&queue->release_work, nvmet_tcp_release_queue_work);
1889	INIT_WORK(&queue->io_work, nvmet_tcp_io_work);
1890	kref_init(&queue->kref);
1891	queue->sock = newsock;
1892	queue->port = port;
1893	queue->nr_cmds = 0;
1894	spin_lock_init(&queue->state_lock);
1895	if (queue->port->nport->disc_addr.tsas.tcp.sectype ==
1896	    NVMF_TCP_SECTYPE_TLS13)
1897		queue->state = NVMET_TCP_Q_TLS_HANDSHAKE;
1898	else
1899		queue->state = NVMET_TCP_Q_CONNECTING;
1900	INIT_LIST_HEAD(&queue->free_list);
1901	init_llist_head(&queue->resp_list);
1902	INIT_LIST_HEAD(&queue->resp_send_list);
1903
1904	sock_file = sock_alloc_file(queue->sock, O_CLOEXEC, NULL);
1905	if (IS_ERR(sock_file)) {
1906		ret = PTR_ERR(sock_file);
1907		goto out_free_queue;
1908	}
1909
1910	queue->idx = ida_alloc(&nvmet_tcp_queue_ida, GFP_KERNEL);
1911	if (queue->idx < 0) {
1912		ret = queue->idx;
1913		goto out_sock;
1914	}
1915
1916	ret = nvmet_tcp_alloc_cmd(queue, &queue->connect);
1917	if (ret)
1918		goto out_ida_remove;
1919
1920	ret = nvmet_sq_init(&queue->nvme_sq);
1921	if (ret)
1922		goto out_free_connect;
1923
1924	nvmet_prepare_receive_pdu(queue);
1925
1926	mutex_lock(&nvmet_tcp_queue_mutex);
1927	list_add_tail(&queue->queue_list, &nvmet_tcp_queue_list);
1928	mutex_unlock(&nvmet_tcp_queue_mutex);
1929
1930	INIT_DELAYED_WORK(&queue->tls_handshake_tmo_work,
1931			  nvmet_tcp_tls_handshake_timeout);
1932#ifdef CONFIG_NVME_TARGET_TCP_TLS
1933	if (queue->state == NVMET_TCP_Q_TLS_HANDSHAKE) {
1934		struct sock *sk = queue->sock->sk;
1935
1936		/* Restore the default callbacks before starting upcall */
1937		read_lock_bh(&sk->sk_callback_lock);
1938		sk->sk_user_data = NULL;
1939		sk->sk_data_ready = port->data_ready;
1940		read_unlock_bh(&sk->sk_callback_lock);
1941		if (!nvmet_tcp_try_peek_pdu(queue)) {
1942			if (!nvmet_tcp_tls_handshake(queue))
1943				return;
1944			/* TLS handshake failed, terminate the connection */
1945			goto out_destroy_sq;
1946		}
1947		/* Not a TLS connection, continue with normal processing */
1948		queue->state = NVMET_TCP_Q_CONNECTING;
1949	}
1950#endif
1951
1952	ret = nvmet_tcp_set_queue_sock(queue);
1953	if (ret)
1954		goto out_destroy_sq;
1955
1956	return;
1957out_destroy_sq:
1958	mutex_lock(&nvmet_tcp_queue_mutex);
1959	list_del_init(&queue->queue_list);
1960	mutex_unlock(&nvmet_tcp_queue_mutex);
1961	nvmet_sq_destroy(&queue->nvme_sq);
1962out_free_connect:
1963	nvmet_tcp_free_cmd(&queue->connect);
1964out_ida_remove:
1965	ida_free(&nvmet_tcp_queue_ida, queue->idx);
1966out_sock:
1967	fput(queue->sock->file);
1968out_free_queue:
1969	kfree(queue);
1970out_release:
1971	pr_err("failed to allocate queue, error %d\n", ret);
1972	if (!sock_file)
1973		sock_release(newsock);
1974}
1975
1976static void nvmet_tcp_accept_work(struct work_struct *w)
1977{
1978	struct nvmet_tcp_port *port =
1979		container_of(w, struct nvmet_tcp_port, accept_work);
1980	struct socket *newsock;
1981	int ret;
1982
1983	while (true) {
1984		ret = kernel_accept(port->sock, &newsock, O_NONBLOCK);
1985		if (ret < 0) {
1986			if (ret != -EAGAIN)
1987				pr_warn("failed to accept err=%d\n", ret);
1988			return;
1989		}
1990		nvmet_tcp_alloc_queue(port, newsock);
1991	}
1992}
1993
1994static void nvmet_tcp_listen_data_ready(struct sock *sk)
1995{
1996	struct nvmet_tcp_port *port;
1997
1998	trace_sk_data_ready(sk);
1999
2000	read_lock_bh(&sk->sk_callback_lock);
2001	port = sk->sk_user_data;
2002	if (!port)
2003		goto out;
2004
2005	if (sk->sk_state == TCP_LISTEN)
2006		queue_work(nvmet_wq, &port->accept_work);
2007out:
2008	read_unlock_bh(&sk->sk_callback_lock);
2009}
2010
2011static int nvmet_tcp_add_port(struct nvmet_port *nport)
2012{
2013	struct nvmet_tcp_port *port;
2014	__kernel_sa_family_t af;
2015	int ret;
2016
2017	port = kzalloc(sizeof(*port), GFP_KERNEL);
2018	if (!port)
2019		return -ENOMEM;
2020
2021	switch (nport->disc_addr.adrfam) {
2022	case NVMF_ADDR_FAMILY_IP4:
2023		af = AF_INET;
2024		break;
2025	case NVMF_ADDR_FAMILY_IP6:
2026		af = AF_INET6;
2027		break;
2028	default:
2029		pr_err("address family %d not supported\n",
2030				nport->disc_addr.adrfam);
2031		ret = -EINVAL;
2032		goto err_port;
2033	}
2034
2035	ret = inet_pton_with_scope(&init_net, af, nport->disc_addr.traddr,
2036			nport->disc_addr.trsvcid, &port->addr);
2037	if (ret) {
2038		pr_err("malformed ip/port passed: %s:%s\n",
2039			nport->disc_addr.traddr, nport->disc_addr.trsvcid);
2040		goto err_port;
2041	}
2042
2043	port->nport = nport;
2044	INIT_WORK(&port->accept_work, nvmet_tcp_accept_work);
2045	if (port->nport->inline_data_size < 0)
2046		port->nport->inline_data_size = NVMET_TCP_DEF_INLINE_DATA_SIZE;
2047
2048	ret = sock_create(port->addr.ss_family, SOCK_STREAM,
2049				IPPROTO_TCP, &port->sock);
2050	if (ret) {
2051		pr_err("failed to create a socket\n");
2052		goto err_port;
2053	}
2054
2055	port->sock->sk->sk_user_data = port;
2056	port->data_ready = port->sock->sk->sk_data_ready;
2057	port->sock->sk->sk_data_ready = nvmet_tcp_listen_data_ready;
2058	sock_set_reuseaddr(port->sock->sk);
2059	tcp_sock_set_nodelay(port->sock->sk);
2060	if (so_priority > 0)
2061		sock_set_priority(port->sock->sk, so_priority);
2062
2063	ret = kernel_bind(port->sock, (struct sockaddr *)&port->addr,
2064			sizeof(port->addr));
2065	if (ret) {
2066		pr_err("failed to bind port socket %d\n", ret);
2067		goto err_sock;
2068	}
2069
2070	ret = kernel_listen(port->sock, NVMET_TCP_BACKLOG);
2071	if (ret) {
2072		pr_err("failed to listen %d on port sock\n", ret);
2073		goto err_sock;
2074	}
2075
2076	nport->priv = port;
2077	pr_info("enabling port %d (%pISpc)\n",
2078		le16_to_cpu(nport->disc_addr.portid), &port->addr);
2079
2080	return 0;
2081
2082err_sock:
2083	sock_release(port->sock);
2084err_port:
2085	kfree(port);
2086	return ret;
2087}
2088
2089static void nvmet_tcp_destroy_port_queues(struct nvmet_tcp_port *port)
2090{
2091	struct nvmet_tcp_queue *queue;
2092
2093	mutex_lock(&nvmet_tcp_queue_mutex);
2094	list_for_each_entry(queue, &nvmet_tcp_queue_list, queue_list)
2095		if (queue->port == port)
2096			kernel_sock_shutdown(queue->sock, SHUT_RDWR);
2097	mutex_unlock(&nvmet_tcp_queue_mutex);
2098}
2099
2100static void nvmet_tcp_remove_port(struct nvmet_port *nport)
2101{
2102	struct nvmet_tcp_port *port = nport->priv;
2103
2104	write_lock_bh(&port->sock->sk->sk_callback_lock);
2105	port->sock->sk->sk_data_ready = port->data_ready;
2106	port->sock->sk->sk_user_data = NULL;
2107	write_unlock_bh(&port->sock->sk->sk_callback_lock);
2108	cancel_work_sync(&port->accept_work);
2109	/*
2110	 * Destroy the remaining queues, which are not belong to any
2111	 * controller yet.
2112	 */
2113	nvmet_tcp_destroy_port_queues(port);
2114
2115	sock_release(port->sock);
2116	kfree(port);
2117}
2118
2119static void nvmet_tcp_delete_ctrl(struct nvmet_ctrl *ctrl)
2120{
2121	struct nvmet_tcp_queue *queue;
2122
2123	mutex_lock(&nvmet_tcp_queue_mutex);
2124	list_for_each_entry(queue, &nvmet_tcp_queue_list, queue_list)
2125		if (queue->nvme_sq.ctrl == ctrl)
2126			kernel_sock_shutdown(queue->sock, SHUT_RDWR);
2127	mutex_unlock(&nvmet_tcp_queue_mutex);
2128}
2129
2130static u16 nvmet_tcp_install_queue(struct nvmet_sq *sq)
2131{
2132	struct nvmet_tcp_queue *queue =
2133		container_of(sq, struct nvmet_tcp_queue, nvme_sq);
2134
2135	if (sq->qid == 0) {
2136		struct nvmet_tcp_queue *q;
2137		int pending = 0;
2138
2139		/* Check for pending controller teardown */
2140		mutex_lock(&nvmet_tcp_queue_mutex);
2141		list_for_each_entry(q, &nvmet_tcp_queue_list, queue_list) {
2142			if (q->nvme_sq.ctrl == sq->ctrl &&
2143			    q->state == NVMET_TCP_Q_DISCONNECTING)
2144				pending++;
2145		}
2146		mutex_unlock(&nvmet_tcp_queue_mutex);
2147		if (pending > NVMET_TCP_BACKLOG)
2148			return NVME_SC_CONNECT_CTRL_BUSY;
2149	}
2150
2151	queue->nr_cmds = sq->size * 2;
2152	if (nvmet_tcp_alloc_cmds(queue))
2153		return NVME_SC_INTERNAL;
2154	return 0;
2155}
2156
2157static void nvmet_tcp_disc_port_addr(struct nvmet_req *req,
2158		struct nvmet_port *nport, char *traddr)
2159{
2160	struct nvmet_tcp_port *port = nport->priv;
2161
2162	if (inet_addr_is_any((struct sockaddr *)&port->addr)) {
2163		struct nvmet_tcp_cmd *cmd =
2164			container_of(req, struct nvmet_tcp_cmd, req);
2165		struct nvmet_tcp_queue *queue = cmd->queue;
2166
2167		sprintf(traddr, "%pISc", (struct sockaddr *)&queue->sockaddr);
2168	} else {
2169		memcpy(traddr, nport->disc_addr.traddr, NVMF_TRADDR_SIZE);
2170	}
2171}
2172
2173static const struct nvmet_fabrics_ops nvmet_tcp_ops = {
2174	.owner			= THIS_MODULE,
2175	.type			= NVMF_TRTYPE_TCP,
2176	.msdbd			= 1,
2177	.add_port		= nvmet_tcp_add_port,
2178	.remove_port		= nvmet_tcp_remove_port,
2179	.queue_response		= nvmet_tcp_queue_response,
2180	.delete_ctrl		= nvmet_tcp_delete_ctrl,
2181	.install_queue		= nvmet_tcp_install_queue,
2182	.disc_traddr		= nvmet_tcp_disc_port_addr,
2183};
2184
2185static int __init nvmet_tcp_init(void)
2186{
2187	int ret;
2188
2189	nvmet_tcp_wq = alloc_workqueue("nvmet_tcp_wq",
2190				WQ_MEM_RECLAIM | WQ_HIGHPRI, 0);
2191	if (!nvmet_tcp_wq)
2192		return -ENOMEM;
2193
2194	ret = nvmet_register_transport(&nvmet_tcp_ops);
2195	if (ret)
2196		goto err;
2197
2198	return 0;
2199err:
2200	destroy_workqueue(nvmet_tcp_wq);
2201	return ret;
2202}
2203
2204static void __exit nvmet_tcp_exit(void)
2205{
2206	struct nvmet_tcp_queue *queue;
2207
2208	nvmet_unregister_transport(&nvmet_tcp_ops);
2209
2210	flush_workqueue(nvmet_wq);
2211	mutex_lock(&nvmet_tcp_queue_mutex);
2212	list_for_each_entry(queue, &nvmet_tcp_queue_list, queue_list)
2213		kernel_sock_shutdown(queue->sock, SHUT_RDWR);
2214	mutex_unlock(&nvmet_tcp_queue_mutex);
2215	flush_workqueue(nvmet_wq);
2216
2217	destroy_workqueue(nvmet_tcp_wq);
2218	ida_destroy(&nvmet_tcp_queue_ida);
2219}
2220
2221module_init(nvmet_tcp_init);
2222module_exit(nvmet_tcp_exit);
2223
2224MODULE_DESCRIPTION("NVMe target TCP transport driver");
2225MODULE_LICENSE("GPL v2");
2226MODULE_ALIAS("nvmet-transport-3"); /* 3 == NVMF_TRTYPE_TCP */
2227