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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
[linux/fpc-iii.git] / drivers / scsi / iscsi_tcp.c
blob4842fc0e809d1cf6846ba531165953f1dd11f993
1 /*
2 * iSCSI Initiator over TCP/IP Data-Path
3 *
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
9 *
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.
14 *
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.
19 *
20 * See the file COPYING included with this distribution for more details.
21 *
22 * Credits:
23 * Christoph Hellwig
24 * FUJITA Tomonori
25 * Arne Redlich
26 * Zhenyu Wang
27 */
28
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 <net/tcp.h>
41 #include <scsi/scsi_cmnd.h>
42 #include <scsi/scsi_device.h>
43 #include <scsi/scsi_host.h>
44 #include <scsi/scsi.h>
45 #include <scsi/scsi_transport_iscsi.h>
46
47 #include "iscsi_tcp.h"
48
49 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
50 "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
51 "Alex Aizman <itn780@yahoo.com>");
52 MODULE_DESCRIPTION("iSCSI/TCP data-path");
53 MODULE_LICENSE("GPL");
54
55 static struct scsi_transport_template *iscsi_sw_tcp_scsi_transport;
56 static struct scsi_host_template iscsi_sw_tcp_sht;
57 static struct iscsi_transport iscsi_sw_tcp_transport;
58
59 static unsigned int iscsi_max_lun = ~0;
60 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
61
62 static int iscsi_sw_tcp_dbg;
63 module_param_named(debug_iscsi_tcp, iscsi_sw_tcp_dbg, int,
64 S_IRUGO | S_IWUSR);
65 MODULE_PARM_DESC(debug_iscsi_tcp, "Turn on debugging for iscsi_tcp module "
66 "Set to 1 to turn on, and zero to turn off. Default is off.");
67
68 #define ISCSI_SW_TCP_DBG(_conn, dbg_fmt, arg...) \
69 do { \
70 if (iscsi_sw_tcp_dbg) \
71 iscsi_conn_printk(KERN_INFO, _conn, \
72 "%s " dbg_fmt, \
73 __func__, ##arg); \
74 } while (0);
75
76
77 /**
78 * iscsi_sw_tcp_recv - TCP receive in sendfile fashion
79 * @rd_desc: read descriptor
80 * @skb: socket buffer
81 * @offset: offset in skb
82 * @len: skb->len - offset
83 */
84 static int iscsi_sw_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
85 unsigned int offset, size_t len)
86 {
87 struct iscsi_conn *conn = rd_desc->arg.data;
88 unsigned int consumed, total_consumed = 0;
89 int status;
90
91 ISCSI_SW_TCP_DBG(conn, "in %d bytes\n", skb->len - offset);
92
93 do {
94 status = 0;
95 consumed = iscsi_tcp_recv_skb(conn, skb, offset, 0, &status);
96 offset += consumed;
97 total_consumed += consumed;
98 } while (consumed != 0 && status != ISCSI_TCP_SKB_DONE);
99
100 ISCSI_SW_TCP_DBG(conn, "read %d bytes status %d\n",
101 skb->len - offset, status);
102 return total_consumed;
103 }
104
105 /**
106 * iscsi_sw_sk_state_check - check socket state
107 * @sk: socket
108 *
109 * If the socket is in CLOSE or CLOSE_WAIT we should
110 * not close the connection if there is still some
111 * data pending.
112 *
113 * Must be called with sk_callback_lock.
114 */
115 static inline int iscsi_sw_sk_state_check(struct sock *sk)
116 {
117 struct iscsi_conn *conn = sk->sk_user_data;
118
119 if ((sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) &&
120 (conn->session->state != ISCSI_STATE_LOGGING_OUT) &&
121 !atomic_read(&sk->sk_rmem_alloc)) {
122 ISCSI_SW_TCP_DBG(conn, "TCP_CLOSE|TCP_CLOSE_WAIT\n");
123 iscsi_conn_failure(conn, ISCSI_ERR_TCP_CONN_CLOSE);
124 return -ECONNRESET;
125 }
126 return 0;
127 }
128
129 static void iscsi_sw_tcp_data_ready(struct sock *sk)
130 {
131 struct iscsi_conn *conn;
132 struct iscsi_tcp_conn *tcp_conn;
133 read_descriptor_t rd_desc;
134
135 read_lock_bh(&sk->sk_callback_lock);
136 conn = sk->sk_user_data;
137 if (!conn) {
138 read_unlock_bh(&sk->sk_callback_lock);
139 return;
140 }
141 tcp_conn = conn->dd_data;
142
143 /*
144 * Use rd_desc to pass 'conn' to iscsi_tcp_recv.
145 * We set count to 1 because we want the network layer to
146 * hand us all the skbs that are available. iscsi_tcp_recv
147 * handled pdus that cross buffers or pdus that still need data.
148 */
149 rd_desc.arg.data = conn;
150 rd_desc.count = 1;
151 tcp_read_sock(sk, &rd_desc, iscsi_sw_tcp_recv);
152
153 iscsi_sw_sk_state_check(sk);
154
155 /* If we had to (atomically) map a highmem page,
156 * unmap it now. */
157 iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
158 read_unlock_bh(&sk->sk_callback_lock);
159 }
160
161 static void iscsi_sw_tcp_state_change(struct sock *sk)
162 {
163 struct iscsi_tcp_conn *tcp_conn;
164 struct iscsi_sw_tcp_conn *tcp_sw_conn;
165 struct iscsi_conn *conn;
166 struct iscsi_session *session;
167 void (*old_state_change)(struct sock *);
168
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;
174 }
175 session = conn->session;
176
177 iscsi_sw_sk_state_check(sk);
178
179 tcp_conn = conn->dd_data;
180 tcp_sw_conn = tcp_conn->dd_data;
181 old_state_change = tcp_sw_conn->old_state_change;
182
183 read_unlock_bh(&sk->sk_callback_lock);
184
185 old_state_change(sk);
186 }
187
188 /**
189 * iscsi_write_space - Called when more output buffer space is available
190 * @sk: socket space is available for
191 **/
192 static void iscsi_sw_tcp_write_space(struct sock *sk)
193 {
194 struct iscsi_conn *conn;
195 struct iscsi_tcp_conn *tcp_conn;
196 struct iscsi_sw_tcp_conn *tcp_sw_conn;
197 void (*old_write_space)(struct sock *);
198
199 read_lock_bh(&sk->sk_callback_lock);
200 conn = sk->sk_user_data;
201 if (!conn) {
202 read_unlock_bh(&sk->sk_callback_lock);
203 return;
204 }
205
206 tcp_conn = conn->dd_data;
207 tcp_sw_conn = tcp_conn->dd_data;
208 old_write_space = tcp_sw_conn->old_write_space;
209 read_unlock_bh(&sk->sk_callback_lock);
210
211 old_write_space(sk);
212
213 ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n");
214 iscsi_conn_queue_work(conn);
215 }
216
217 static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn)
218 {
219 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
220 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
221 struct sock *sk = tcp_sw_conn->sock->sk;
222
223 /* assign new callbacks */
224 write_lock_bh(&sk->sk_callback_lock);
225 sk->sk_user_data = conn;
226 tcp_sw_conn->old_data_ready = sk->sk_data_ready;
227 tcp_sw_conn->old_state_change = sk->sk_state_change;
228 tcp_sw_conn->old_write_space = sk->sk_write_space;
229 sk->sk_data_ready = iscsi_sw_tcp_data_ready;
230 sk->sk_state_change = iscsi_sw_tcp_state_change;
231 sk->sk_write_space = iscsi_sw_tcp_write_space;
232 write_unlock_bh(&sk->sk_callback_lock);
233 }
234
235 static void
236 iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_conn *conn)
237 {
238 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
239 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
240 struct sock *sk = tcp_sw_conn->sock->sk;
241
242 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
243 write_lock_bh(&sk->sk_callback_lock);
244 sk->sk_user_data = NULL;
245 sk->sk_data_ready = tcp_sw_conn->old_data_ready;
246 sk->sk_state_change = tcp_sw_conn->old_state_change;
247 sk->sk_write_space = tcp_sw_conn->old_write_space;
248 sk->sk_no_check_tx = 0;
249 write_unlock_bh(&sk->sk_callback_lock);
250 }
251
252 /**
253 * iscsi_sw_tcp_xmit_segment - transmit segment
254 * @tcp_conn: the iSCSI TCP connection
255 * @segment: the buffer to transmnit
256 *
257 * This function transmits as much of the buffer as
258 * the network layer will accept, and returns the number of
259 * bytes transmitted.
260 *
261 * If CRC hashing is enabled, the function will compute the
262 * hash as it goes. When the entire segment has been transmitted,
263 * it will retrieve the hash value and send it as well.
264 */
265 static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
266 struct iscsi_segment *segment)
267 {
268 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
269 struct socket *sk = tcp_sw_conn->sock;
270 unsigned int copied = 0;
271 int r = 0;
272
273 while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) {
274 struct scatterlist *sg;
275 unsigned int offset, copy;
276 int flags = 0;
277
278 r = 0;
279 offset = segment->copied;
280 copy = segment->size - offset;
281
282 if (segment->total_copied + segment->size < segment->total_size)
283 flags |= MSG_MORE;
284
285 /* Use sendpage if we can; else fall back to sendmsg */
286 if (!segment->data) {
287 sg = segment->sg;
288 offset += segment->sg_offset + sg->offset;
289 r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset,
290 copy, flags);
291 } else {
292 struct msghdr msg = { .msg_flags = flags };
293 struct kvec iov = {
294 .iov_base = segment->data + offset,
295 .iov_len = copy
296 };
297
298 r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
299 }
300
301 if (r < 0) {
302 iscsi_tcp_segment_unmap(segment);
303 return r;
304 }
305 copied += r;
306 }
307 return copied;
308 }
309
310 /**
311 * iscsi_sw_tcp_xmit - TCP transmit
312 **/
313 static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn)
314 {
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;
320
321 while (1) {
322 rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment);
323 /*
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.
327 */
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;
335
336 consumed += rc;
337
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;
343 }
344 }
345 }
346
347 ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed);
348
349 conn->txdata_octets += consumed;
350 return consumed;
351
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;
358 }
359
360 /**
361 * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit
362 */
363 static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn)
364 {
365 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
366 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
367 struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
368
369 return segment->total_copied - segment->total_size;
370 }
371
372 static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task)
373 {
374 struct iscsi_conn *conn = task->conn;
375 unsigned int noreclaim_flag;
376 int rc = 0;
377
378 noreclaim_flag = memalloc_noreclaim_save();
379
380 while (iscsi_sw_tcp_xmit_qlen(conn)) {
381 rc = iscsi_sw_tcp_xmit(conn);
382 if (rc == 0) {
383 rc = -EAGAIN;
384 break;
385 }
386 if (rc < 0)
387 break;
388 rc = 0;
389 }
390
391 memalloc_noreclaim_restore(noreclaim_flag);
392 return rc;
393 }
394
395 /*
396 * This is called when we're done sending the header.
397 * Simply copy the data_segment to the send segment, and return.
398 */
399 static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
400 struct iscsi_segment *segment)
401 {
402 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
403
404 tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment;
405 ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn,
406 "Header done. Next segment size %u total_size %u\n",
407 tcp_sw_conn->out.segment.size,
408 tcp_sw_conn->out.segment.total_size);
409 return 0;
410 }
411
412 static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr,
413 size_t hdrlen)
414 {
415 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
416 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
417
418 ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ?
419 "digest enabled" : "digest disabled");
420
421 /* Clear the data segment - needs to be filled in by the
422 * caller using iscsi_tcp_send_data_prep() */
423 memset(&tcp_sw_conn->out.data_segment, 0,
424 sizeof(struct iscsi_segment));
425
426 /* If header digest is enabled, compute the CRC and
427 * place the digest into the same buffer. We make
428 * sure that both iscsi_tcp_task and mtask have
429 * sufficient room.
430 */
431 if (conn->hdrdgst_en) {
432 iscsi_tcp_dgst_header(tcp_sw_conn->tx_hash, hdr, hdrlen,
433 hdr + hdrlen);
434 hdrlen += ISCSI_DIGEST_SIZE;
435 }
436
437 /* Remember header pointer for later, when we need
438 * to decide whether there's a payload to go along
439 * with the header. */
440 tcp_sw_conn->out.hdr = hdr;
441
442 iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen,
443 iscsi_sw_tcp_send_hdr_done, NULL);
444 }
445
446 /*
447 * Prepare the send buffer for the payload data.
448 * Padding and checksumming will all be taken care
449 * of by the iscsi_segment routines.
450 */
451 static int
452 iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
453 unsigned int count, unsigned int offset,
454 unsigned int len)
455 {
456 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
457 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
458 struct ahash_request *tx_hash = NULL;
459 unsigned int hdr_spec_len;
460
461 ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len,
462 conn->datadgst_en ?
463 "digest enabled" : "digest disabled");
464
465 /* Make sure the datalen matches what the caller
466 said he would send. */
467 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
468 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
469
470 if (conn->datadgst_en)
471 tx_hash = tcp_sw_conn->tx_hash;
472
473 return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment,
474 sg, count, offset, len,
475 NULL, tx_hash);
476 }
477
478 static void
479 iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data,
480 size_t len)
481 {
482 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
483 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
484 struct ahash_request *tx_hash = NULL;
485 unsigned int hdr_spec_len;
486
487 ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ?
488 "digest enabled" : "digest disabled");
489
490 /* Make sure the datalen matches what the caller
491 said he would send. */
492 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
493 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
494
495 if (conn->datadgst_en)
496 tx_hash = tcp_sw_conn->tx_hash;
497
498 iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment,
499 data, len, NULL, tx_hash);
500 }
501
502 static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task,
503 unsigned int offset, unsigned int count)
504 {
505 struct iscsi_conn *conn = task->conn;
506 int err = 0;
507
508 iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
509
510 if (!count)
511 return 0;
512
513 if (!task->sc)
514 iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count);
515 else {
516 struct scsi_data_buffer *sdb = scsi_out(task->sc);
517
518 err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl,
519 sdb->table.nents, offset,
520 count);
521 }
522
523 if (err) {
524 /* got invalid offset/len */
525 return -EIO;
526 }
527 return 0;
528 }
529
530 static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
531 {
532 struct iscsi_tcp_task *tcp_task = task->dd_data;
533
534 task->hdr = task->dd_data + sizeof(*tcp_task);
535 task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE;
536 return 0;
537 }
538
539 static struct iscsi_cls_conn *
540 iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session,
541 uint32_t conn_idx)
542 {
543 struct iscsi_conn *conn;
544 struct iscsi_cls_conn *cls_conn;
545 struct iscsi_tcp_conn *tcp_conn;
546 struct iscsi_sw_tcp_conn *tcp_sw_conn;
547 struct crypto_ahash *tfm;
548
549 cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn),
550 conn_idx);
551 if (!cls_conn)
552 return NULL;
553 conn = cls_conn->dd_data;
554 tcp_conn = conn->dd_data;
555 tcp_sw_conn = tcp_conn->dd_data;
556
557 tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC);
558 if (IS_ERR(tfm))
559 goto free_conn;
560
561 tcp_sw_conn->tx_hash = ahash_request_alloc(tfm, GFP_KERNEL);
562 if (!tcp_sw_conn->tx_hash)
563 goto free_tfm;
564 ahash_request_set_callback(tcp_sw_conn->tx_hash, 0, NULL, NULL);
565
566 tcp_sw_conn->rx_hash = ahash_request_alloc(tfm, GFP_KERNEL);
567 if (!tcp_sw_conn->rx_hash)
568 goto free_tx_hash;
569 ahash_request_set_callback(tcp_sw_conn->rx_hash, 0, NULL, NULL);
570
571 tcp_conn->rx_hash = tcp_sw_conn->rx_hash;
572
573 return cls_conn;
574
575 free_tx_hash:
576 ahash_request_free(tcp_sw_conn->tx_hash);
577 free_tfm:
578 crypto_free_ahash(tfm);
579 free_conn:
580 iscsi_conn_printk(KERN_ERR, conn,
581 "Could not create connection due to crc32c "
582 "loading error. Make sure the crc32c "
583 "module is built as a module or into the "
584 "kernel\n");
585 iscsi_tcp_conn_teardown(cls_conn);
586 return NULL;
587 }
588
589 static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn)
590 {
591 struct iscsi_session *session = conn->session;
592 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
593 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
594 struct socket *sock = tcp_sw_conn->sock;
595
596 if (!sock)
597 return;
598
599 sock_hold(sock->sk);
600 iscsi_sw_tcp_conn_restore_callbacks(conn);
601 sock_put(sock->sk);
602
603 spin_lock_bh(&session->frwd_lock);
604 tcp_sw_conn->sock = NULL;
605 spin_unlock_bh(&session->frwd_lock);
606 sockfd_put(sock);
607 }
608
609 static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
610 {
611 struct iscsi_conn *conn = cls_conn->dd_data;
612 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
613 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
614
615 iscsi_sw_tcp_release_conn(conn);
616
617 ahash_request_free(tcp_sw_conn->rx_hash);
618 if (tcp_sw_conn->tx_hash) {
619 struct crypto_ahash *tfm;
620
621 tfm = crypto_ahash_reqtfm(tcp_sw_conn->tx_hash);
622 ahash_request_free(tcp_sw_conn->tx_hash);
623 crypto_free_ahash(tfm);
624 }
625
626 iscsi_tcp_conn_teardown(cls_conn);
627 }
628
629 static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
630 {
631 struct iscsi_conn *conn = cls_conn->dd_data;
632 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
633 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
634 struct socket *sock = tcp_sw_conn->sock;
635
636 /* userspace may have goofed up and not bound us */
637 if (!sock)
638 return;
639
640 sock->sk->sk_err = EIO;
641 wake_up_interruptible(sk_sleep(sock->sk));
642
643 /* stop xmit side */
644 iscsi_suspend_tx(conn);
645
646 /* stop recv side and release socket */
647 iscsi_sw_tcp_release_conn(conn);
648
649 iscsi_conn_stop(cls_conn, flag);
650 }
651
652 static int
653 iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session,
654 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
655 int is_leading)
656 {
657 struct iscsi_session *session = cls_session->dd_data;
658 struct iscsi_conn *conn = cls_conn->dd_data;
659 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
660 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
661 struct sock *sk;
662 struct socket *sock;
663 int err;
664
665 /* lookup for existing socket */
666 sock = sockfd_lookup((int)transport_eph, &err);
667 if (!sock) {
668 iscsi_conn_printk(KERN_ERR, conn,
669 "sockfd_lookup failed %d\n", err);
670 return -EEXIST;
671 }
672
673 err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
674 if (err)
675 goto free_socket;
676
677 spin_lock_bh(&session->frwd_lock);
678 /* bind iSCSI connection and socket */
679 tcp_sw_conn->sock = sock;
680 spin_unlock_bh(&session->frwd_lock);
681
682 /* setup Socket parameters */
683 sk = sock->sk;
684 sk->sk_reuse = SK_CAN_REUSE;
685 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
686 sk->sk_allocation = GFP_ATOMIC;
687 sk_set_memalloc(sk);
688
689 iscsi_sw_tcp_conn_set_callbacks(conn);
690 tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage;
691 /*
692 * set receive state machine into initial state
693 */
694 iscsi_tcp_hdr_recv_prep(tcp_conn);
695 return 0;
696
697 free_socket:
698 sockfd_put(sock);
699 return err;
700 }
701
702 static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn,
703 enum iscsi_param param, char *buf,
704 int buflen)
705 {
706 struct iscsi_conn *conn = cls_conn->dd_data;
707 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
708 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
709
710 switch(param) {
711 case ISCSI_PARAM_HDRDGST_EN:
712 iscsi_set_param(cls_conn, param, buf, buflen);
713 break;
714 case ISCSI_PARAM_DATADGST_EN:
715 iscsi_set_param(cls_conn, param, buf, buflen);
716 tcp_sw_conn->sendpage = conn->datadgst_en ?
717 sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
718 break;
719 case ISCSI_PARAM_MAX_R2T:
720 return iscsi_tcp_set_max_r2t(conn, buf);
721 default:
722 return iscsi_set_param(cls_conn, param, buf, buflen);
723 }
724
725 return 0;
726 }
727
728 static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
729 enum iscsi_param param, char *buf)
730 {
731 struct iscsi_conn *conn = cls_conn->dd_data;
732 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
733 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
734 struct sockaddr_in6 addr;
735 int rc, len;
736
737 switch(param) {
738 case ISCSI_PARAM_CONN_PORT:
739 case ISCSI_PARAM_CONN_ADDRESS:
740 case ISCSI_PARAM_LOCAL_PORT:
741 spin_lock_bh(&conn->session->frwd_lock);
742 if (!tcp_sw_conn || !tcp_sw_conn->sock) {
743 spin_unlock_bh(&conn->session->frwd_lock);
744 return -ENOTCONN;
745 }
746 if (param == ISCSI_PARAM_LOCAL_PORT)
747 rc = kernel_getsockname(tcp_sw_conn->sock,
748 (struct sockaddr *)&addr, &len);
749 else
750 rc = kernel_getpeername(tcp_sw_conn->sock,
751 (struct sockaddr *)&addr, &len);
752 spin_unlock_bh(&conn->session->frwd_lock);
753 if (rc)
754 return rc;
755
756 return iscsi_conn_get_addr_param((struct sockaddr_storage *)
757 &addr, param, buf);
758 default:
759 return iscsi_conn_get_param(cls_conn, param, buf);
760 }
761
762 return 0;
763 }
764
765 static int iscsi_sw_tcp_host_get_param(struct Scsi_Host *shost,
766 enum iscsi_host_param param, char *buf)
767 {
768 struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(shost);
769 struct iscsi_session *session = tcp_sw_host->session;
770 struct iscsi_conn *conn;
771 struct iscsi_tcp_conn *tcp_conn;
772 struct iscsi_sw_tcp_conn *tcp_sw_conn;
773 struct sockaddr_in6 addr;
774 int rc, len;
775
776 switch (param) {
777 case ISCSI_HOST_PARAM_IPADDRESS:
778 if (!session)
779 return -ENOTCONN;
780
781 spin_lock_bh(&session->frwd_lock);
782 conn = session->leadconn;
783 if (!conn) {
784 spin_unlock_bh(&session->frwd_lock);
785 return -ENOTCONN;
786 }
787 tcp_conn = conn->dd_data;
788
789 tcp_sw_conn = tcp_conn->dd_data;
790 if (!tcp_sw_conn->sock) {
791 spin_unlock_bh(&session->frwd_lock);
792 return -ENOTCONN;
793 }
794
795 rc = kernel_getsockname(tcp_sw_conn->sock,
796 (struct sockaddr *)&addr, &len);
797 spin_unlock_bh(&session->frwd_lock);
798 if (rc)
799 return rc;
800
801 return iscsi_conn_get_addr_param((struct sockaddr_storage *)
802 &addr, param, buf);
803 default:
804 return iscsi_host_get_param(shost, param, buf);
805 }
806
807 return 0;
808 }
809
810 static void
811 iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
812 struct iscsi_stats *stats)
813 {
814 struct iscsi_conn *conn = cls_conn->dd_data;
815 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
816 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
817
818 stats->custom_length = 3;
819 strcpy(stats->custom[0].desc, "tx_sendpage_failures");
820 stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt;
821 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
822 stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt;
823 strcpy(stats->custom[2].desc, "eh_abort_cnt");
824 stats->custom[2].value = conn->eh_abort_cnt;
825
826 iscsi_tcp_conn_get_stats(cls_conn, stats);
827 }
828
829 static struct iscsi_cls_session *
830 iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
831 uint16_t qdepth, uint32_t initial_cmdsn)
832 {
833 struct iscsi_cls_session *cls_session;
834 struct iscsi_session *session;
835 struct iscsi_sw_tcp_host *tcp_sw_host;
836 struct Scsi_Host *shost;
837
838 if (ep) {
839 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep);
840 return NULL;
841 }
842
843 shost = iscsi_host_alloc(&iscsi_sw_tcp_sht,
844 sizeof(struct iscsi_sw_tcp_host), 1);
845 if (!shost)
846 return NULL;
847 shost->transportt = iscsi_sw_tcp_scsi_transport;
848 shost->cmd_per_lun = qdepth;
849 shost->max_lun = iscsi_max_lun;
850 shost->max_id = 0;
851 shost->max_channel = 0;
852 shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
853
854 if (iscsi_host_add(shost, NULL))
855 goto free_host;
856
857 cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost,
858 cmds_max, 0,
859 sizeof(struct iscsi_tcp_task) +
860 sizeof(struct iscsi_sw_tcp_hdrbuf),
861 initial_cmdsn, 0);
862 if (!cls_session)
863 goto remove_host;
864 session = cls_session->dd_data;
865 tcp_sw_host = iscsi_host_priv(shost);
866 tcp_sw_host->session = session;
867
868 shost->can_queue = session->scsi_cmds_max;
869 if (iscsi_tcp_r2tpool_alloc(session))
870 goto remove_session;
871 return cls_session;
872
873 remove_session:
874 iscsi_session_teardown(cls_session);
875 remove_host:
876 iscsi_host_remove(shost);
877 free_host:
878 iscsi_host_free(shost);
879 return NULL;
880 }
881
882 static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session)
883 {
884 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
885
886 iscsi_tcp_r2tpool_free(cls_session->dd_data);
887 iscsi_session_teardown(cls_session);
888
889 iscsi_host_remove(shost);
890 iscsi_host_free(shost);
891 }
892
893 static umode_t iscsi_sw_tcp_attr_is_visible(int param_type, int param)
894 {
895 switch (param_type) {
896 case ISCSI_HOST_PARAM:
897 switch (param) {
898 case ISCSI_HOST_PARAM_NETDEV_NAME:
899 case ISCSI_HOST_PARAM_HWADDRESS:
900 case ISCSI_HOST_PARAM_IPADDRESS:
901 case ISCSI_HOST_PARAM_INITIATOR_NAME:
902 return S_IRUGO;
903 default:
904 return 0;
905 }
906 case ISCSI_PARAM:
907 switch (param) {
908 case ISCSI_PARAM_MAX_RECV_DLENGTH:
909 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
910 case ISCSI_PARAM_HDRDGST_EN:
911 case ISCSI_PARAM_DATADGST_EN:
912 case ISCSI_PARAM_CONN_ADDRESS:
913 case ISCSI_PARAM_CONN_PORT:
914 case ISCSI_PARAM_LOCAL_PORT:
915 case ISCSI_PARAM_EXP_STATSN:
916 case ISCSI_PARAM_PERSISTENT_ADDRESS:
917 case ISCSI_PARAM_PERSISTENT_PORT:
918 case ISCSI_PARAM_PING_TMO:
919 case ISCSI_PARAM_RECV_TMO:
920 case ISCSI_PARAM_INITIAL_R2T_EN:
921 case ISCSI_PARAM_MAX_R2T:
922 case ISCSI_PARAM_IMM_DATA_EN:
923 case ISCSI_PARAM_FIRST_BURST:
924 case ISCSI_PARAM_MAX_BURST:
925 case ISCSI_PARAM_PDU_INORDER_EN:
926 case ISCSI_PARAM_DATASEQ_INORDER_EN:
927 case ISCSI_PARAM_ERL:
928 case ISCSI_PARAM_TARGET_NAME:
929 case ISCSI_PARAM_TPGT:
930 case ISCSI_PARAM_USERNAME:
931 case ISCSI_PARAM_PASSWORD:
932 case ISCSI_PARAM_USERNAME_IN:
933 case ISCSI_PARAM_PASSWORD_IN:
934 case ISCSI_PARAM_FAST_ABORT:
935 case ISCSI_PARAM_ABORT_TMO:
936 case ISCSI_PARAM_LU_RESET_TMO:
937 case ISCSI_PARAM_TGT_RESET_TMO:
938 case ISCSI_PARAM_IFACE_NAME:
939 case ISCSI_PARAM_INITIATOR_NAME:
940 return S_IRUGO;
941 default:
942 return 0;
943 }
944 }
945
946 return 0;
947 }
948
949 static int iscsi_sw_tcp_slave_alloc(struct scsi_device *sdev)
950 {
951 set_bit(QUEUE_FLAG_BIDI, &sdev->request_queue->queue_flags);
952 return 0;
953 }
954
955 static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev)
956 {
957 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY);
958 blk_queue_dma_alignment(sdev->request_queue, 0);
959 return 0;
960 }
961
962 static struct scsi_host_template iscsi_sw_tcp_sht = {
963 .module = THIS_MODULE,
964 .name = "iSCSI Initiator over TCP/IP",
965 .queuecommand = iscsi_queuecommand,
966 .change_queue_depth = scsi_change_queue_depth,
967 .can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1,
968 .sg_tablesize = 4096,
969 .max_sectors = 0xFFFF,
970 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
971 .eh_timed_out = iscsi_eh_cmd_timed_out,
972 .eh_abort_handler = iscsi_eh_abort,
973 .eh_device_reset_handler= iscsi_eh_device_reset,
974 .eh_target_reset_handler = iscsi_eh_recover_target,
975 .use_clustering = DISABLE_CLUSTERING,
976 .slave_alloc = iscsi_sw_tcp_slave_alloc,
977 .slave_configure = iscsi_sw_tcp_slave_configure,
978 .target_alloc = iscsi_target_alloc,
979 .proc_name = "iscsi_tcp",
980 .this_id = -1,
981 .track_queue_depth = 1,
982 };
983
984 static struct iscsi_transport iscsi_sw_tcp_transport = {
985 .owner = THIS_MODULE,
986 .name = "tcp",
987 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
988 | CAP_DATADGST,
989 /* session management */
990 .create_session = iscsi_sw_tcp_session_create,
991 .destroy_session = iscsi_sw_tcp_session_destroy,
992 /* connection management */
993 .create_conn = iscsi_sw_tcp_conn_create,
994 .bind_conn = iscsi_sw_tcp_conn_bind,
995 .destroy_conn = iscsi_sw_tcp_conn_destroy,
996 .attr_is_visible = iscsi_sw_tcp_attr_is_visible,
997 .set_param = iscsi_sw_tcp_conn_set_param,
998 .get_conn_param = iscsi_sw_tcp_conn_get_param,
999 .get_session_param = iscsi_session_get_param,
1000 .start_conn = iscsi_conn_start,
1001 .stop_conn = iscsi_sw_tcp_conn_stop,
1002 /* iscsi host params */
1003 .get_host_param = iscsi_sw_tcp_host_get_param,
1004 .set_host_param = iscsi_host_set_param,
1005 /* IO */
1006 .send_pdu = iscsi_conn_send_pdu,
1007 .get_stats = iscsi_sw_tcp_conn_get_stats,
1008 /* iscsi task/cmd helpers */
1009 .init_task = iscsi_tcp_task_init,
1010 .xmit_task = iscsi_tcp_task_xmit,
1011 .cleanup_task = iscsi_tcp_cleanup_task,
1012 /* low level pdu helpers */
1013 .xmit_pdu = iscsi_sw_tcp_pdu_xmit,
1014 .init_pdu = iscsi_sw_tcp_pdu_init,
1015 .alloc_pdu = iscsi_sw_tcp_pdu_alloc,
1016 /* recovery */
1017 .session_recovery_timedout = iscsi_session_recovery_timedout,
1018 };
1019
1020 static int __init iscsi_sw_tcp_init(void)
1021 {
1022 if (iscsi_max_lun < 1) {
1023 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
1024 iscsi_max_lun);
1025 return -EINVAL;
1026 }
1027
1028 iscsi_sw_tcp_scsi_transport = iscsi_register_transport(
1029 &iscsi_sw_tcp_transport);
1030 if (!iscsi_sw_tcp_scsi_transport)
1031 return -ENODEV;
1032
1033 return 0;
1034 }
1035
1036 static void __exit iscsi_sw_tcp_exit(void)
1037 {
1038 iscsi_unregister_transport(&iscsi_sw_tcp_transport);
1039 }
1040
1041 module_init(iscsi_sw_tcp_init);
1042 module_exit(iscsi_sw_tcp_exit);
Linux with added FPC-III support