Linux 4.18.10
[linux/fpc-iii.git] / drivers / scsi / iscsi_tcp.c
blobb025a0b7434174cea0096b23fad34aa18a22de20
1 /*
2 * iSCSI Initiator over TCP/IP Data-Path
4 * Copyright (C) 2004 Dmitry Yusupov
5 * Copyright (C) 2004 Alex Aizman
6 * Copyright (C) 2005 - 2006 Mike Christie
7 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
8 * maintained by open-iscsi@googlegroups.com
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published
12 * by the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
20 * See the file COPYING included with this distribution for more details.
22 * Credits:
23 * Christoph Hellwig
24 * FUJITA Tomonori
25 * Arne Redlich
26 * Zhenyu Wang
29 #include <crypto/hash.h>
30 #include <linux/types.h>
31 #include <linux/inet.h>
32 #include <linux/slab.h>
33 #include <linux/sched/mm.h>
34 #include <linux/file.h>
35 #include <linux/blkdev.h>
36 #include <linux/delay.h>
37 #include <linux/kfifo.h>
38 #include <linux/scatterlist.h>
39 #include <linux/module.h>
40 #include <linux/backing-dev.h>
41 #include <net/tcp.h>
42 #include <scsi/scsi_cmnd.h>
43 #include <scsi/scsi_device.h>
44 #include <scsi/scsi_host.h>
45 #include <scsi/scsi.h>
46 #include <scsi/scsi_transport_iscsi.h>
48 #include "iscsi_tcp.h"
50 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
51 "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
52 "Alex Aizman <itn780@yahoo.com>");
53 MODULE_DESCRIPTION("iSCSI/TCP data-path");
54 MODULE_LICENSE("GPL");
56 static struct scsi_transport_template *iscsi_sw_tcp_scsi_transport;
57 static struct scsi_host_template iscsi_sw_tcp_sht;
58 static struct iscsi_transport iscsi_sw_tcp_transport;
60 static unsigned int iscsi_max_lun = ~0;
61 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
63 static int iscsi_sw_tcp_dbg;
64 module_param_named(debug_iscsi_tcp, iscsi_sw_tcp_dbg, int,
65 S_IRUGO | S_IWUSR);
66 MODULE_PARM_DESC(debug_iscsi_tcp, "Turn on debugging for iscsi_tcp module "
67 "Set to 1 to turn on, and zero to turn off. Default is off.");
69 #define ISCSI_SW_TCP_DBG(_conn, dbg_fmt, arg...) \
70 do { \
71 if (iscsi_sw_tcp_dbg) \
72 iscsi_conn_printk(KERN_INFO, _conn, \
73 "%s " dbg_fmt, \
74 __func__, ##arg); \
75 } while (0);
78 /**
79 * iscsi_sw_tcp_recv - TCP receive in sendfile fashion
80 * @rd_desc: read descriptor
81 * @skb: socket buffer
82 * @offset: offset in skb
83 * @len: skb->len - offset
85 static int iscsi_sw_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
86 unsigned int offset, size_t len)
88 struct iscsi_conn *conn = rd_desc->arg.data;
89 unsigned int consumed, total_consumed = 0;
90 int status;
92 ISCSI_SW_TCP_DBG(conn, "in %d bytes\n", skb->len - offset);
94 do {
95 status = 0;
96 consumed = iscsi_tcp_recv_skb(conn, skb, offset, 0, &status);
97 offset += consumed;
98 total_consumed += consumed;
99 } while (consumed != 0 && status != ISCSI_TCP_SKB_DONE);
101 ISCSI_SW_TCP_DBG(conn, "read %d bytes status %d\n",
102 skb->len - offset, status);
103 return total_consumed;
107 * iscsi_sw_sk_state_check - check socket state
108 * @sk: socket
110 * If the socket is in CLOSE or CLOSE_WAIT we should
111 * not close the connection if there is still some
112 * data pending.
114 * Must be called with sk_callback_lock.
116 static inline int iscsi_sw_sk_state_check(struct sock *sk)
118 struct iscsi_conn *conn = sk->sk_user_data;
120 if ((sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) &&
121 (conn->session->state != ISCSI_STATE_LOGGING_OUT) &&
122 !atomic_read(&sk->sk_rmem_alloc)) {
123 ISCSI_SW_TCP_DBG(conn, "TCP_CLOSE|TCP_CLOSE_WAIT\n");
124 iscsi_conn_failure(conn, ISCSI_ERR_TCP_CONN_CLOSE);
125 return -ECONNRESET;
127 return 0;
130 static void iscsi_sw_tcp_data_ready(struct sock *sk)
132 struct iscsi_conn *conn;
133 struct iscsi_tcp_conn *tcp_conn;
134 read_descriptor_t rd_desc;
136 read_lock_bh(&sk->sk_callback_lock);
137 conn = sk->sk_user_data;
138 if (!conn) {
139 read_unlock_bh(&sk->sk_callback_lock);
140 return;
142 tcp_conn = conn->dd_data;
145 * Use rd_desc to pass 'conn' to iscsi_tcp_recv.
146 * We set count to 1 because we want the network layer to
147 * hand us all the skbs that are available. iscsi_tcp_recv
148 * handled pdus that cross buffers or pdus that still need data.
150 rd_desc.arg.data = conn;
151 rd_desc.count = 1;
152 tcp_read_sock(sk, &rd_desc, iscsi_sw_tcp_recv);
154 iscsi_sw_sk_state_check(sk);
156 /* If we had to (atomically) map a highmem page,
157 * unmap it now. */
158 iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
159 read_unlock_bh(&sk->sk_callback_lock);
162 static void iscsi_sw_tcp_state_change(struct sock *sk)
164 struct iscsi_tcp_conn *tcp_conn;
165 struct iscsi_sw_tcp_conn *tcp_sw_conn;
166 struct iscsi_conn *conn;
167 void (*old_state_change)(struct sock *);
169 read_lock_bh(&sk->sk_callback_lock);
170 conn = sk->sk_user_data;
171 if (!conn) {
172 read_unlock_bh(&sk->sk_callback_lock);
173 return;
176 iscsi_sw_sk_state_check(sk);
178 tcp_conn = conn->dd_data;
179 tcp_sw_conn = tcp_conn->dd_data;
180 old_state_change = tcp_sw_conn->old_state_change;
182 read_unlock_bh(&sk->sk_callback_lock);
184 old_state_change(sk);
188 * iscsi_write_space - Called when more output buffer space is available
189 * @sk: socket space is available for
191 static void iscsi_sw_tcp_write_space(struct sock *sk)
193 struct iscsi_conn *conn;
194 struct iscsi_tcp_conn *tcp_conn;
195 struct iscsi_sw_tcp_conn *tcp_sw_conn;
196 void (*old_write_space)(struct sock *);
198 read_lock_bh(&sk->sk_callback_lock);
199 conn = sk->sk_user_data;
200 if (!conn) {
201 read_unlock_bh(&sk->sk_callback_lock);
202 return;
205 tcp_conn = conn->dd_data;
206 tcp_sw_conn = tcp_conn->dd_data;
207 old_write_space = tcp_sw_conn->old_write_space;
208 read_unlock_bh(&sk->sk_callback_lock);
210 old_write_space(sk);
212 ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n");
213 iscsi_conn_queue_work(conn);
216 static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn)
218 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
219 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
220 struct sock *sk = tcp_sw_conn->sock->sk;
222 /* assign new callbacks */
223 write_lock_bh(&sk->sk_callback_lock);
224 sk->sk_user_data = conn;
225 tcp_sw_conn->old_data_ready = sk->sk_data_ready;
226 tcp_sw_conn->old_state_change = sk->sk_state_change;
227 tcp_sw_conn->old_write_space = sk->sk_write_space;
228 sk->sk_data_ready = iscsi_sw_tcp_data_ready;
229 sk->sk_state_change = iscsi_sw_tcp_state_change;
230 sk->sk_write_space = iscsi_sw_tcp_write_space;
231 write_unlock_bh(&sk->sk_callback_lock);
234 static void
235 iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_conn *conn)
237 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
238 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
239 struct sock *sk = tcp_sw_conn->sock->sk;
241 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
242 write_lock_bh(&sk->sk_callback_lock);
243 sk->sk_user_data = NULL;
244 sk->sk_data_ready = tcp_sw_conn->old_data_ready;
245 sk->sk_state_change = tcp_sw_conn->old_state_change;
246 sk->sk_write_space = tcp_sw_conn->old_write_space;
247 sk->sk_no_check_tx = 0;
248 write_unlock_bh(&sk->sk_callback_lock);
252 * iscsi_sw_tcp_xmit_segment - transmit segment
253 * @tcp_conn: the iSCSI TCP connection
254 * @segment: the buffer to transmnit
256 * This function transmits as much of the buffer as
257 * the network layer will accept, and returns the number of
258 * bytes transmitted.
260 * If CRC hashing is enabled, the function will compute the
261 * hash as it goes. When the entire segment has been transmitted,
262 * it will retrieve the hash value and send it as well.
264 static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
265 struct iscsi_segment *segment)
267 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
268 struct socket *sk = tcp_sw_conn->sock;
269 unsigned int copied = 0;
270 int r = 0;
272 while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) {
273 struct scatterlist *sg;
274 unsigned int offset, copy;
275 int flags = 0;
277 r = 0;
278 offset = segment->copied;
279 copy = segment->size - offset;
281 if (segment->total_copied + segment->size < segment->total_size)
282 flags |= MSG_MORE;
284 /* Use sendpage if we can; else fall back to sendmsg */
285 if (!segment->data) {
286 sg = segment->sg;
287 offset += segment->sg_offset + sg->offset;
288 r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset,
289 copy, flags);
290 } else {
291 struct msghdr msg = { .msg_flags = flags };
292 struct kvec iov = {
293 .iov_base = segment->data + offset,
294 .iov_len = copy
297 r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
300 if (r < 0) {
301 iscsi_tcp_segment_unmap(segment);
302 return r;
304 copied += r;
306 return copied;
310 * iscsi_sw_tcp_xmit - TCP transmit
311 * @conn: iscsi connection
313 static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn)
315 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
316 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
317 struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
318 unsigned int consumed = 0;
319 int rc = 0;
321 while (1) {
322 rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment);
324 * We may not have been able to send data because the conn
325 * is getting stopped. libiscsi will know so propagate err
326 * for it to do the right thing.
328 if (rc == -EAGAIN)
329 return rc;
330 else if (rc < 0) {
331 rc = ISCSI_ERR_XMIT_FAILED;
332 goto error;
333 } else if (rc == 0)
334 break;
336 consumed += rc;
338 if (segment->total_copied >= segment->total_size) {
339 if (segment->done != NULL) {
340 rc = segment->done(tcp_conn, segment);
341 if (rc != 0)
342 goto error;
347 ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed);
349 conn->txdata_octets += consumed;
350 return consumed;
352 error:
353 /* Transmit error. We could initiate error recovery
354 * here. */
355 ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc);
356 iscsi_conn_failure(conn, rc);
357 return -EIO;
361 * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit
362 * @conn: iscsi connection
364 static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn)
366 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
367 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
368 struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
370 return segment->total_copied - segment->total_size;
373 static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task)
375 struct iscsi_conn *conn = task->conn;
376 unsigned int noreclaim_flag;
377 int rc = 0;
379 noreclaim_flag = memalloc_noreclaim_save();
381 while (iscsi_sw_tcp_xmit_qlen(conn)) {
382 rc = iscsi_sw_tcp_xmit(conn);
383 if (rc == 0) {
384 rc = -EAGAIN;
385 break;
387 if (rc < 0)
388 break;
389 rc = 0;
392 memalloc_noreclaim_restore(noreclaim_flag);
393 return rc;
397 * This is called when we're done sending the header.
398 * Simply copy the data_segment to the send segment, and return.
400 static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
401 struct iscsi_segment *segment)
403 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
405 tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment;
406 ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn,
407 "Header done. Next segment size %u total_size %u\n",
408 tcp_sw_conn->out.segment.size,
409 tcp_sw_conn->out.segment.total_size);
410 return 0;
413 static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr,
414 size_t hdrlen)
416 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
417 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
419 ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ?
420 "digest enabled" : "digest disabled");
422 /* Clear the data segment - needs to be filled in by the
423 * caller using iscsi_tcp_send_data_prep() */
424 memset(&tcp_sw_conn->out.data_segment, 0,
425 sizeof(struct iscsi_segment));
427 /* If header digest is enabled, compute the CRC and
428 * place the digest into the same buffer. We make
429 * sure that both iscsi_tcp_task and mtask have
430 * sufficient room.
432 if (conn->hdrdgst_en) {
433 iscsi_tcp_dgst_header(tcp_sw_conn->tx_hash, hdr, hdrlen,
434 hdr + hdrlen);
435 hdrlen += ISCSI_DIGEST_SIZE;
438 /* Remember header pointer for later, when we need
439 * to decide whether there's a payload to go along
440 * with the header. */
441 tcp_sw_conn->out.hdr = hdr;
443 iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen,
444 iscsi_sw_tcp_send_hdr_done, NULL);
448 * Prepare the send buffer for the payload data.
449 * Padding and checksumming will all be taken care
450 * of by the iscsi_segment routines.
452 static int
453 iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
454 unsigned int count, unsigned int offset,
455 unsigned int len)
457 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
458 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
459 struct ahash_request *tx_hash = NULL;
460 unsigned int hdr_spec_len;
462 ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len,
463 conn->datadgst_en ?
464 "digest enabled" : "digest disabled");
466 /* Make sure the datalen matches what the caller
467 said he would send. */
468 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
469 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
471 if (conn->datadgst_en)
472 tx_hash = tcp_sw_conn->tx_hash;
474 return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment,
475 sg, count, offset, len,
476 NULL, tx_hash);
479 static void
480 iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data,
481 size_t len)
483 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
484 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
485 struct ahash_request *tx_hash = NULL;
486 unsigned int hdr_spec_len;
488 ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ?
489 "digest enabled" : "digest disabled");
491 /* Make sure the datalen matches what the caller
492 said he would send. */
493 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
494 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
496 if (conn->datadgst_en)
497 tx_hash = tcp_sw_conn->tx_hash;
499 iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment,
500 data, len, NULL, tx_hash);
503 static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task,
504 unsigned int offset, unsigned int count)
506 struct iscsi_conn *conn = task->conn;
507 int err = 0;
509 iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
511 if (!count)
512 return 0;
514 if (!task->sc)
515 iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count);
516 else {
517 struct scsi_data_buffer *sdb = scsi_out(task->sc);
519 err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl,
520 sdb->table.nents, offset,
521 count);
524 if (err) {
525 /* got invalid offset/len */
526 return -EIO;
528 return 0;
531 static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
533 struct iscsi_tcp_task *tcp_task = task->dd_data;
535 task->hdr = task->dd_data + sizeof(*tcp_task);
536 task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE;
537 return 0;
540 static struct iscsi_cls_conn *
541 iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session,
542 uint32_t conn_idx)
544 struct iscsi_conn *conn;
545 struct iscsi_cls_conn *cls_conn;
546 struct iscsi_tcp_conn *tcp_conn;
547 struct iscsi_sw_tcp_conn *tcp_sw_conn;
548 struct crypto_ahash *tfm;
550 cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn),
551 conn_idx);
552 if (!cls_conn)
553 return NULL;
554 conn = cls_conn->dd_data;
555 tcp_conn = conn->dd_data;
556 tcp_sw_conn = tcp_conn->dd_data;
558 tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC);
559 if (IS_ERR(tfm))
560 goto free_conn;
562 tcp_sw_conn->tx_hash = ahash_request_alloc(tfm, GFP_KERNEL);
563 if (!tcp_sw_conn->tx_hash)
564 goto free_tfm;
565 ahash_request_set_callback(tcp_sw_conn->tx_hash, 0, NULL, NULL);
567 tcp_sw_conn->rx_hash = ahash_request_alloc(tfm, GFP_KERNEL);
568 if (!tcp_sw_conn->rx_hash)
569 goto free_tx_hash;
570 ahash_request_set_callback(tcp_sw_conn->rx_hash, 0, NULL, NULL);
572 tcp_conn->rx_hash = tcp_sw_conn->rx_hash;
574 return cls_conn;
576 free_tx_hash:
577 ahash_request_free(tcp_sw_conn->tx_hash);
578 free_tfm:
579 crypto_free_ahash(tfm);
580 free_conn:
581 iscsi_conn_printk(KERN_ERR, conn,
582 "Could not create connection due to crc32c "
583 "loading error. Make sure the crc32c "
584 "module is built as a module or into the "
585 "kernel\n");
586 iscsi_tcp_conn_teardown(cls_conn);
587 return NULL;
590 static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn)
592 struct iscsi_session *session = conn->session;
593 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
594 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
595 struct socket *sock = tcp_sw_conn->sock;
597 if (!sock)
598 return;
600 sock_hold(sock->sk);
601 iscsi_sw_tcp_conn_restore_callbacks(conn);
602 sock_put(sock->sk);
604 spin_lock_bh(&session->frwd_lock);
605 tcp_sw_conn->sock = NULL;
606 spin_unlock_bh(&session->frwd_lock);
607 sockfd_put(sock);
610 static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
612 struct iscsi_conn *conn = cls_conn->dd_data;
613 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
614 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
616 iscsi_sw_tcp_release_conn(conn);
618 ahash_request_free(tcp_sw_conn->rx_hash);
619 if (tcp_sw_conn->tx_hash) {
620 struct crypto_ahash *tfm;
622 tfm = crypto_ahash_reqtfm(tcp_sw_conn->tx_hash);
623 ahash_request_free(tcp_sw_conn->tx_hash);
624 crypto_free_ahash(tfm);
627 iscsi_tcp_conn_teardown(cls_conn);
630 static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
632 struct iscsi_conn *conn = cls_conn->dd_data;
633 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
634 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
635 struct socket *sock = tcp_sw_conn->sock;
637 /* userspace may have goofed up and not bound us */
638 if (!sock)
639 return;
641 sock->sk->sk_err = EIO;
642 wake_up_interruptible(sk_sleep(sock->sk));
644 /* stop xmit side */
645 iscsi_suspend_tx(conn);
647 /* stop recv side and release socket */
648 iscsi_sw_tcp_release_conn(conn);
650 iscsi_conn_stop(cls_conn, flag);
653 static int
654 iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session,
655 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
656 int is_leading)
658 struct iscsi_session *session = cls_session->dd_data;
659 struct iscsi_conn *conn = cls_conn->dd_data;
660 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
661 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
662 struct sock *sk;
663 struct socket *sock;
664 int err;
666 /* lookup for existing socket */
667 sock = sockfd_lookup((int)transport_eph, &err);
668 if (!sock) {
669 iscsi_conn_printk(KERN_ERR, conn,
670 "sockfd_lookup failed %d\n", err);
671 return -EEXIST;
674 err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
675 if (err)
676 goto free_socket;
678 spin_lock_bh(&session->frwd_lock);
679 /* bind iSCSI connection and socket */
680 tcp_sw_conn->sock = sock;
681 spin_unlock_bh(&session->frwd_lock);
683 /* setup Socket parameters */
684 sk = sock->sk;
685 sk->sk_reuse = SK_CAN_REUSE;
686 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
687 sk->sk_allocation = GFP_ATOMIC;
688 sk_set_memalloc(sk);
690 iscsi_sw_tcp_conn_set_callbacks(conn);
691 tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage;
693 * set receive state machine into initial state
695 iscsi_tcp_hdr_recv_prep(tcp_conn);
696 return 0;
698 free_socket:
699 sockfd_put(sock);
700 return err;
703 static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn,
704 enum iscsi_param param, char *buf,
705 int buflen)
707 struct iscsi_conn *conn = cls_conn->dd_data;
708 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
709 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
711 switch(param) {
712 case ISCSI_PARAM_HDRDGST_EN:
713 iscsi_set_param(cls_conn, param, buf, buflen);
714 break;
715 case ISCSI_PARAM_DATADGST_EN:
716 iscsi_set_param(cls_conn, param, buf, buflen);
717 tcp_sw_conn->sendpage = conn->datadgst_en ?
718 sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
719 break;
720 case ISCSI_PARAM_MAX_R2T:
721 return iscsi_tcp_set_max_r2t(conn, buf);
722 default:
723 return iscsi_set_param(cls_conn, param, buf, buflen);
726 return 0;
729 static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
730 enum iscsi_param param, char *buf)
732 struct iscsi_conn *conn = cls_conn->dd_data;
733 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
734 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
735 struct sockaddr_in6 addr;
736 int rc;
738 switch(param) {
739 case ISCSI_PARAM_CONN_PORT:
740 case ISCSI_PARAM_CONN_ADDRESS:
741 case ISCSI_PARAM_LOCAL_PORT:
742 spin_lock_bh(&conn->session->frwd_lock);
743 if (!tcp_sw_conn || !tcp_sw_conn->sock) {
744 spin_unlock_bh(&conn->session->frwd_lock);
745 return -ENOTCONN;
747 if (param == ISCSI_PARAM_LOCAL_PORT)
748 rc = kernel_getsockname(tcp_sw_conn->sock,
749 (struct sockaddr *)&addr);
750 else
751 rc = kernel_getpeername(tcp_sw_conn->sock,
752 (struct sockaddr *)&addr);
753 spin_unlock_bh(&conn->session->frwd_lock);
754 if (rc < 0)
755 return rc;
757 return iscsi_conn_get_addr_param((struct sockaddr_storage *)
758 &addr, param, buf);
759 default:
760 return iscsi_conn_get_param(cls_conn, param, buf);
763 return 0;
766 static int iscsi_sw_tcp_host_get_param(struct Scsi_Host *shost,
767 enum iscsi_host_param param, char *buf)
769 struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(shost);
770 struct iscsi_session *session = tcp_sw_host->session;
771 struct iscsi_conn *conn;
772 struct iscsi_tcp_conn *tcp_conn;
773 struct iscsi_sw_tcp_conn *tcp_sw_conn;
774 struct sockaddr_in6 addr;
775 int rc;
777 switch (param) {
778 case ISCSI_HOST_PARAM_IPADDRESS:
779 if (!session)
780 return -ENOTCONN;
782 spin_lock_bh(&session->frwd_lock);
783 conn = session->leadconn;
784 if (!conn) {
785 spin_unlock_bh(&session->frwd_lock);
786 return -ENOTCONN;
788 tcp_conn = conn->dd_data;
790 tcp_sw_conn = tcp_conn->dd_data;
791 if (!tcp_sw_conn->sock) {
792 spin_unlock_bh(&session->frwd_lock);
793 return -ENOTCONN;
796 rc = kernel_getsockname(tcp_sw_conn->sock,
797 (struct sockaddr *)&addr);
798 spin_unlock_bh(&session->frwd_lock);
799 if (rc < 0)
800 return rc;
802 return iscsi_conn_get_addr_param((struct sockaddr_storage *)
803 &addr, param, buf);
804 default:
805 return iscsi_host_get_param(shost, param, buf);
808 return 0;
811 static void
812 iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
813 struct iscsi_stats *stats)
815 struct iscsi_conn *conn = cls_conn->dd_data;
816 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
817 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
819 stats->custom_length = 3;
820 strcpy(stats->custom[0].desc, "tx_sendpage_failures");
821 stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt;
822 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
823 stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt;
824 strcpy(stats->custom[2].desc, "eh_abort_cnt");
825 stats->custom[2].value = conn->eh_abort_cnt;
827 iscsi_tcp_conn_get_stats(cls_conn, stats);
830 static struct iscsi_cls_session *
831 iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
832 uint16_t qdepth, uint32_t initial_cmdsn)
834 struct iscsi_cls_session *cls_session;
835 struct iscsi_session *session;
836 struct iscsi_sw_tcp_host *tcp_sw_host;
837 struct Scsi_Host *shost;
839 if (ep) {
840 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep);
841 return NULL;
844 shost = iscsi_host_alloc(&iscsi_sw_tcp_sht,
845 sizeof(struct iscsi_sw_tcp_host), 1);
846 if (!shost)
847 return NULL;
848 shost->transportt = iscsi_sw_tcp_scsi_transport;
849 shost->cmd_per_lun = qdepth;
850 shost->max_lun = iscsi_max_lun;
851 shost->max_id = 0;
852 shost->max_channel = 0;
853 shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
855 if (iscsi_host_add(shost, NULL))
856 goto free_host;
858 cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost,
859 cmds_max, 0,
860 sizeof(struct iscsi_tcp_task) +
861 sizeof(struct iscsi_sw_tcp_hdrbuf),
862 initial_cmdsn, 0);
863 if (!cls_session)
864 goto remove_host;
865 session = cls_session->dd_data;
866 tcp_sw_host = iscsi_host_priv(shost);
867 tcp_sw_host->session = session;
869 shost->can_queue = session->scsi_cmds_max;
870 if (iscsi_tcp_r2tpool_alloc(session))
871 goto remove_session;
872 return cls_session;
874 remove_session:
875 iscsi_session_teardown(cls_session);
876 remove_host:
877 iscsi_host_remove(shost);
878 free_host:
879 iscsi_host_free(shost);
880 return NULL;
883 static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session)
885 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
887 iscsi_tcp_r2tpool_free(cls_session->dd_data);
888 iscsi_session_teardown(cls_session);
890 iscsi_host_remove(shost);
891 iscsi_host_free(shost);
894 static umode_t iscsi_sw_tcp_attr_is_visible(int param_type, int param)
896 switch (param_type) {
897 case ISCSI_HOST_PARAM:
898 switch (param) {
899 case ISCSI_HOST_PARAM_NETDEV_NAME:
900 case ISCSI_HOST_PARAM_HWADDRESS:
901 case ISCSI_HOST_PARAM_IPADDRESS:
902 case ISCSI_HOST_PARAM_INITIATOR_NAME:
903 return S_IRUGO;
904 default:
905 return 0;
907 case ISCSI_PARAM:
908 switch (param) {
909 case ISCSI_PARAM_MAX_RECV_DLENGTH:
910 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
911 case ISCSI_PARAM_HDRDGST_EN:
912 case ISCSI_PARAM_DATADGST_EN:
913 case ISCSI_PARAM_CONN_ADDRESS:
914 case ISCSI_PARAM_CONN_PORT:
915 case ISCSI_PARAM_LOCAL_PORT:
916 case ISCSI_PARAM_EXP_STATSN:
917 case ISCSI_PARAM_PERSISTENT_ADDRESS:
918 case ISCSI_PARAM_PERSISTENT_PORT:
919 case ISCSI_PARAM_PING_TMO:
920 case ISCSI_PARAM_RECV_TMO:
921 case ISCSI_PARAM_INITIAL_R2T_EN:
922 case ISCSI_PARAM_MAX_R2T:
923 case ISCSI_PARAM_IMM_DATA_EN:
924 case ISCSI_PARAM_FIRST_BURST:
925 case ISCSI_PARAM_MAX_BURST:
926 case ISCSI_PARAM_PDU_INORDER_EN:
927 case ISCSI_PARAM_DATASEQ_INORDER_EN:
928 case ISCSI_PARAM_ERL:
929 case ISCSI_PARAM_TARGET_NAME:
930 case ISCSI_PARAM_TPGT:
931 case ISCSI_PARAM_USERNAME:
932 case ISCSI_PARAM_PASSWORD:
933 case ISCSI_PARAM_USERNAME_IN:
934 case ISCSI_PARAM_PASSWORD_IN:
935 case ISCSI_PARAM_FAST_ABORT:
936 case ISCSI_PARAM_ABORT_TMO:
937 case ISCSI_PARAM_LU_RESET_TMO:
938 case ISCSI_PARAM_TGT_RESET_TMO:
939 case ISCSI_PARAM_IFACE_NAME:
940 case ISCSI_PARAM_INITIATOR_NAME:
941 return S_IRUGO;
942 default:
943 return 0;
947 return 0;
950 static int iscsi_sw_tcp_slave_alloc(struct scsi_device *sdev)
952 blk_queue_flag_set(QUEUE_FLAG_BIDI, sdev->request_queue);
953 return 0;
956 static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev)
958 struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(sdev->host);
959 struct iscsi_session *session = tcp_sw_host->session;
960 struct iscsi_conn *conn = session->leadconn;
962 if (conn->datadgst_en)
963 sdev->request_queue->backing_dev_info->capabilities
964 |= BDI_CAP_STABLE_WRITES;
965 blk_queue_dma_alignment(sdev->request_queue, 0);
966 return 0;
969 static struct scsi_host_template iscsi_sw_tcp_sht = {
970 .module = THIS_MODULE,
971 .name = "iSCSI Initiator over TCP/IP",
972 .queuecommand = iscsi_queuecommand,
973 .change_queue_depth = scsi_change_queue_depth,
974 .can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1,
975 .sg_tablesize = 4096,
976 .max_sectors = 0xFFFF,
977 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
978 .eh_timed_out = iscsi_eh_cmd_timed_out,
979 .eh_abort_handler = iscsi_eh_abort,
980 .eh_device_reset_handler= iscsi_eh_device_reset,
981 .eh_target_reset_handler = iscsi_eh_recover_target,
982 .use_clustering = DISABLE_CLUSTERING,
983 .slave_alloc = iscsi_sw_tcp_slave_alloc,
984 .slave_configure = iscsi_sw_tcp_slave_configure,
985 .target_alloc = iscsi_target_alloc,
986 .proc_name = "iscsi_tcp",
987 .this_id = -1,
988 .track_queue_depth = 1,
991 static struct iscsi_transport iscsi_sw_tcp_transport = {
992 .owner = THIS_MODULE,
993 .name = "tcp",
994 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
995 | CAP_DATADGST,
996 /* session management */
997 .create_session = iscsi_sw_tcp_session_create,
998 .destroy_session = iscsi_sw_tcp_session_destroy,
999 /* connection management */
1000 .create_conn = iscsi_sw_tcp_conn_create,
1001 .bind_conn = iscsi_sw_tcp_conn_bind,
1002 .destroy_conn = iscsi_sw_tcp_conn_destroy,
1003 .attr_is_visible = iscsi_sw_tcp_attr_is_visible,
1004 .set_param = iscsi_sw_tcp_conn_set_param,
1005 .get_conn_param = iscsi_sw_tcp_conn_get_param,
1006 .get_session_param = iscsi_session_get_param,
1007 .start_conn = iscsi_conn_start,
1008 .stop_conn = iscsi_sw_tcp_conn_stop,
1009 /* iscsi host params */
1010 .get_host_param = iscsi_sw_tcp_host_get_param,
1011 .set_host_param = iscsi_host_set_param,
1012 /* IO */
1013 .send_pdu = iscsi_conn_send_pdu,
1014 .get_stats = iscsi_sw_tcp_conn_get_stats,
1015 /* iscsi task/cmd helpers */
1016 .init_task = iscsi_tcp_task_init,
1017 .xmit_task = iscsi_tcp_task_xmit,
1018 .cleanup_task = iscsi_tcp_cleanup_task,
1019 /* low level pdu helpers */
1020 .xmit_pdu = iscsi_sw_tcp_pdu_xmit,
1021 .init_pdu = iscsi_sw_tcp_pdu_init,
1022 .alloc_pdu = iscsi_sw_tcp_pdu_alloc,
1023 /* recovery */
1024 .session_recovery_timedout = iscsi_session_recovery_timedout,
1027 static int __init iscsi_sw_tcp_init(void)
1029 if (iscsi_max_lun < 1) {
1030 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
1031 iscsi_max_lun);
1032 return -EINVAL;
1035 iscsi_sw_tcp_scsi_transport = iscsi_register_transport(
1036 &iscsi_sw_tcp_transport);
1037 if (!iscsi_sw_tcp_scsi_transport)
1038 return -ENODEV;
1040 return 0;
1043 static void __exit iscsi_sw_tcp_exit(void)
1045 iscsi_unregister_transport(&iscsi_sw_tcp_transport);
1048 module_init(iscsi_sw_tcp_init);
1049 module_exit(iscsi_sw_tcp_exit);