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md: Fix unfortunate interaction with evms
[linux-2.6/mini2440.git] / drivers / scsi / iscsi_tcp.c
blob518dbd91df85ae73db24157464aabdb62ebbedd1
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 <linux/types.h>
30 #include <linux/inet.h>
31 #include <linux/file.h>
32 #include <linux/blkdev.h>
33 #include <linux/crypto.h>
34 #include <linux/delay.h>
35 #include <linux/kfifo.h>
36 #include <linux/scatterlist.h>
37 #include <net/tcp.h>
38 #include <scsi/scsi_cmnd.h>
39 #include <scsi/scsi_device.h>
40 #include <scsi/scsi_host.h>
41 #include <scsi/scsi.h>
42 #include <scsi/scsi_transport_iscsi.h>
43
44 #include "iscsi_tcp.h"
45
46 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
47 "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
48 "Alex Aizman <itn780@yahoo.com>");
49 MODULE_DESCRIPTION("iSCSI/TCP data-path");
50 MODULE_LICENSE("GPL");
51
52 static struct scsi_transport_template *iscsi_sw_tcp_scsi_transport;
53 static struct scsi_host_template iscsi_sw_tcp_sht;
54 static struct iscsi_transport iscsi_sw_tcp_transport;
55
56 static unsigned int iscsi_max_lun = 512;
57 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
58
59 static int iscsi_sw_tcp_dbg;
60 module_param_named(debug_iscsi_tcp, iscsi_sw_tcp_dbg, int,
61 S_IRUGO | S_IWUSR);
62 MODULE_PARM_DESC(debug_iscsi_tcp, "Turn on debugging for iscsi_tcp module "
63 "Set to 1 to turn on, and zero to turn off. Default is off.");
64
65 #define ISCSI_SW_TCP_DBG(_conn, dbg_fmt, arg...) \
66 do { \
67 if (iscsi_sw_tcp_dbg) \
68 iscsi_conn_printk(KERN_INFO, _conn, \
69 "%s " dbg_fmt, \
70 __func__, ##arg); \
71 } while (0);
72
73
74 /**
75 * iscsi_sw_tcp_recv - TCP receive in sendfile fashion
76 * @rd_desc: read descriptor
77 * @skb: socket buffer
78 * @offset: offset in skb
79 * @len: skb->len - offset
80 */
81 static int iscsi_sw_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
82 unsigned int offset, size_t len)
83 {
84 struct iscsi_conn *conn = rd_desc->arg.data;
85 unsigned int consumed, total_consumed = 0;
86 int status;
87
88 ISCSI_SW_TCP_DBG(conn, "in %d bytes\n", skb->len - offset);
89
90 do {
91 status = 0;
92 consumed = iscsi_tcp_recv_skb(conn, skb, offset, 0, &status);
93 offset += consumed;
94 total_consumed += consumed;
95 } while (consumed != 0 && status != ISCSI_TCP_SKB_DONE);
96
97 ISCSI_SW_TCP_DBG(conn, "read %d bytes status %d\n",
98 skb->len - offset, status);
99 return total_consumed;
100 }
101
102 static void iscsi_sw_tcp_data_ready(struct sock *sk, int flag)
103 {
104 struct iscsi_conn *conn = sk->sk_user_data;
105 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
106 read_descriptor_t rd_desc;
107
108 read_lock(&sk->sk_callback_lock);
109
110 /*
111 * Use rd_desc to pass 'conn' to iscsi_tcp_recv.
112 * We set count to 1 because we want the network layer to
113 * hand us all the skbs that are available. iscsi_tcp_recv
114 * handled pdus that cross buffers or pdus that still need data.
115 */
116 rd_desc.arg.data = conn;
117 rd_desc.count = 1;
118 tcp_read_sock(sk, &rd_desc, iscsi_sw_tcp_recv);
119
120 read_unlock(&sk->sk_callback_lock);
121
122 /* If we had to (atomically) map a highmem page,
123 * unmap it now. */
124 iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
125 }
126
127 static void iscsi_sw_tcp_state_change(struct sock *sk)
128 {
129 struct iscsi_tcp_conn *tcp_conn;
130 struct iscsi_sw_tcp_conn *tcp_sw_conn;
131 struct iscsi_conn *conn;
132 struct iscsi_session *session;
133 void (*old_state_change)(struct sock *);
134
135 read_lock(&sk->sk_callback_lock);
136
137 conn = (struct iscsi_conn*)sk->sk_user_data;
138 session = conn->session;
139
140 if ((sk->sk_state == TCP_CLOSE_WAIT ||
141 sk->sk_state == TCP_CLOSE) &&
142 !atomic_read(&sk->sk_rmem_alloc)) {
143 ISCSI_SW_TCP_DBG(conn, "iscsi_tcp_state_change: "
144 "TCP_CLOSE|TCP_CLOSE_WAIT\n");
145 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
146 }
147
148 tcp_conn = conn->dd_data;
149 tcp_sw_conn = tcp_conn->dd_data;
150 old_state_change = tcp_sw_conn->old_state_change;
151
152 read_unlock(&sk->sk_callback_lock);
153
154 old_state_change(sk);
155 }
156
157 /**
158 * iscsi_write_space - Called when more output buffer space is available
159 * @sk: socket space is available for
160 **/
161 static void iscsi_sw_tcp_write_space(struct sock *sk)
162 {
163 struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
164 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
165 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
166
167 tcp_sw_conn->old_write_space(sk);
168 ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n");
169 iscsi_conn_queue_work(conn);
170 }
171
172 static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn)
173 {
174 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
175 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
176 struct sock *sk = tcp_sw_conn->sock->sk;
177
178 /* assign new callbacks */
179 write_lock_bh(&sk->sk_callback_lock);
180 sk->sk_user_data = conn;
181 tcp_sw_conn->old_data_ready = sk->sk_data_ready;
182 tcp_sw_conn->old_state_change = sk->sk_state_change;
183 tcp_sw_conn->old_write_space = sk->sk_write_space;
184 sk->sk_data_ready = iscsi_sw_tcp_data_ready;
185 sk->sk_state_change = iscsi_sw_tcp_state_change;
186 sk->sk_write_space = iscsi_sw_tcp_write_space;
187 write_unlock_bh(&sk->sk_callback_lock);
188 }
189
190 static void
191 iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_sw_tcp_conn *tcp_sw_conn)
192 {
193 struct sock *sk = tcp_sw_conn->sock->sk;
194
195 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
196 write_lock_bh(&sk->sk_callback_lock);
197 sk->sk_user_data = NULL;
198 sk->sk_data_ready = tcp_sw_conn->old_data_ready;
199 sk->sk_state_change = tcp_sw_conn->old_state_change;
200 sk->sk_write_space = tcp_sw_conn->old_write_space;
201 sk->sk_no_check = 0;
202 write_unlock_bh(&sk->sk_callback_lock);
203 }
204
205 /**
206 * iscsi_sw_tcp_xmit_segment - transmit segment
207 * @tcp_conn: the iSCSI TCP connection
208 * @segment: the buffer to transmnit
209 *
210 * This function transmits as much of the buffer as
211 * the network layer will accept, and returns the number of
212 * bytes transmitted.
213 *
214 * If CRC hashing is enabled, the function will compute the
215 * hash as it goes. When the entire segment has been transmitted,
216 * it will retrieve the hash value and send it as well.
217 */
218 static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
219 struct iscsi_segment *segment)
220 {
221 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
222 struct socket *sk = tcp_sw_conn->sock;
223 unsigned int copied = 0;
224 int r = 0;
225
226 while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) {
227 struct scatterlist *sg;
228 unsigned int offset, copy;
229 int flags = 0;
230
231 r = 0;
232 offset = segment->copied;
233 copy = segment->size - offset;
234
235 if (segment->total_copied + segment->size < segment->total_size)
236 flags |= MSG_MORE;
237
238 /* Use sendpage if we can; else fall back to sendmsg */
239 if (!segment->data) {
240 sg = segment->sg;
241 offset += segment->sg_offset + sg->offset;
242 r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset,
243 copy, flags);
244 } else {
245 struct msghdr msg = { .msg_flags = flags };
246 struct kvec iov = {
247 .iov_base = segment->data + offset,
248 .iov_len = copy
249 };
250
251 r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
252 }
253
254 if (r < 0) {
255 iscsi_tcp_segment_unmap(segment);
256 return r;
257 }
258 copied += r;
259 }
260 return copied;
261 }
262
263 /**
264 * iscsi_sw_tcp_xmit - TCP transmit
265 **/
266 static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn)
267 {
268 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
269 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
270 struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
271 unsigned int consumed = 0;
272 int rc = 0;
273
274 while (1) {
275 rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment);
276 /*
277 * We may not have been able to send data because the conn
278 * is getting stopped. libiscsi will know so propogate err
279 * for it to do the right thing.
280 */
281 if (rc == -EAGAIN)
282 return rc;
283 else if (rc < 0) {
284 rc = ISCSI_ERR_XMIT_FAILED;
285 goto error;
286 } else if (rc == 0)
287 break;
288
289 consumed += rc;
290
291 if (segment->total_copied >= segment->total_size) {
292 if (segment->done != NULL) {
293 rc = segment->done(tcp_conn, segment);
294 if (rc != 0)
295 goto error;
296 }
297 }
298 }
299
300 ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed);
301
302 conn->txdata_octets += consumed;
303 return consumed;
304
305 error:
306 /* Transmit error. We could initiate error recovery
307 * here. */
308 ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc);
309 iscsi_conn_failure(conn, rc);
310 return -EIO;
311 }
312
313 /**
314 * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit
315 */
316 static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn)
317 {
318 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
319 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
320 struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
321
322 return segment->total_copied - segment->total_size;
323 }
324
325 static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task)
326 {
327 struct iscsi_conn *conn = task->conn;
328 int rc;
329
330 while (iscsi_sw_tcp_xmit_qlen(conn)) {
331 rc = iscsi_sw_tcp_xmit(conn);
332 if (rc == 0)
333 return -EAGAIN;
334 if (rc < 0)
335 return rc;
336 }
337
338 return 0;
339 }
340
341 /*
342 * This is called when we're done sending the header.
343 * Simply copy the data_segment to the send segment, and return.
344 */
345 static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
346 struct iscsi_segment *segment)
347 {
348 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
349
350 tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment;
351 ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn,
352 "Header done. Next segment size %u total_size %u\n",
353 tcp_sw_conn->out.segment.size,
354 tcp_sw_conn->out.segment.total_size);
355 return 0;
356 }
357
358 static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr,
359 size_t hdrlen)
360 {
361 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
362 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
363
364 ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ?
365 "digest enabled" : "digest disabled");
366
367 /* Clear the data segment - needs to be filled in by the
368 * caller using iscsi_tcp_send_data_prep() */
369 memset(&tcp_sw_conn->out.data_segment, 0,
370 sizeof(struct iscsi_segment));
371
372 /* If header digest is enabled, compute the CRC and
373 * place the digest into the same buffer. We make
374 * sure that both iscsi_tcp_task and mtask have
375 * sufficient room.
376 */
377 if (conn->hdrdgst_en) {
378 iscsi_tcp_dgst_header(&tcp_sw_conn->tx_hash, hdr, hdrlen,
379 hdr + hdrlen);
380 hdrlen += ISCSI_DIGEST_SIZE;
381 }
382
383 /* Remember header pointer for later, when we need
384 * to decide whether there's a payload to go along
385 * with the header. */
386 tcp_sw_conn->out.hdr = hdr;
387
388 iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen,
389 iscsi_sw_tcp_send_hdr_done, NULL);
390 }
391
392 /*
393 * Prepare the send buffer for the payload data.
394 * Padding and checksumming will all be taken care
395 * of by the iscsi_segment routines.
396 */
397 static int
398 iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
399 unsigned int count, unsigned int offset,
400 unsigned int len)
401 {
402 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
403 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
404 struct hash_desc *tx_hash = NULL;
405 unsigned int hdr_spec_len;
406
407 ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len,
408 conn->datadgst_en ?
409 "digest enabled" : "digest disabled");
410
411 /* Make sure the datalen matches what the caller
412 said he would send. */
413 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
414 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
415
416 if (conn->datadgst_en)
417 tx_hash = &tcp_sw_conn->tx_hash;
418
419 return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment,
420 sg, count, offset, len,
421 NULL, tx_hash);
422 }
423
424 static void
425 iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data,
426 size_t len)
427 {
428 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
429 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
430 struct hash_desc *tx_hash = NULL;
431 unsigned int hdr_spec_len;
432
433 ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ?
434 "digest enabled" : "digest disabled");
435
436 /* Make sure the datalen matches what the caller
437 said he would send. */
438 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
439 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
440
441 if (conn->datadgst_en)
442 tx_hash = &tcp_sw_conn->tx_hash;
443
444 iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment,
445 data, len, NULL, tx_hash);
446 }
447
448 static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task,
449 unsigned int offset, unsigned int count)
450 {
451 struct iscsi_conn *conn = task->conn;
452 int err = 0;
453
454 iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
455
456 if (!count)
457 return 0;
458
459 if (!task->sc)
460 iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count);
461 else {
462 struct scsi_data_buffer *sdb = scsi_out(task->sc);
463
464 err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl,
465 sdb->table.nents, offset,
466 count);
467 }
468
469 if (err) {
470 /* got invalid offset/len */
471 return -EIO;
472 }
473 return 0;
474 }
475
476 static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
477 {
478 struct iscsi_tcp_task *tcp_task = task->dd_data;
479
480 task->hdr = task->dd_data + sizeof(*tcp_task);
481 task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE;
482 return 0;
483 }
484
485 static struct iscsi_cls_conn *
486 iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session,
487 uint32_t conn_idx)
488 {
489 struct iscsi_conn *conn;
490 struct iscsi_cls_conn *cls_conn;
491 struct iscsi_tcp_conn *tcp_conn;
492 struct iscsi_sw_tcp_conn *tcp_sw_conn;
493
494 cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn),
495 conn_idx);
496 if (!cls_conn)
497 return NULL;
498 conn = cls_conn->dd_data;
499 tcp_conn = conn->dd_data;
500 tcp_sw_conn = tcp_conn->dd_data;
501
502 tcp_sw_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0,
503 CRYPTO_ALG_ASYNC);
504 tcp_sw_conn->tx_hash.flags = 0;
505 if (IS_ERR(tcp_sw_conn->tx_hash.tfm))
506 goto free_conn;
507
508 tcp_sw_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0,
509 CRYPTO_ALG_ASYNC);
510 tcp_sw_conn->rx_hash.flags = 0;
511 if (IS_ERR(tcp_sw_conn->rx_hash.tfm))
512 goto free_tx_tfm;
513 tcp_conn->rx_hash = &tcp_sw_conn->rx_hash;
514
515 return cls_conn;
516
517 free_tx_tfm:
518 crypto_free_hash(tcp_sw_conn->tx_hash.tfm);
519 free_conn:
520 iscsi_conn_printk(KERN_ERR, conn,
521 "Could not create connection due to crc32c "
522 "loading error. Make sure the crc32c "
523 "module is built as a module or into the "
524 "kernel\n");
525 iscsi_tcp_conn_teardown(cls_conn);
526 return NULL;
527 }
528
529 static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn)
530 {
531 struct iscsi_session *session = conn->session;
532 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
533 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
534 struct socket *sock = tcp_sw_conn->sock;
535
536 if (!sock)
537 return;
538
539 sock_hold(sock->sk);
540 iscsi_sw_tcp_conn_restore_callbacks(tcp_sw_conn);
541 sock_put(sock->sk);
542
543 spin_lock_bh(&session->lock);
544 tcp_sw_conn->sock = NULL;
545 spin_unlock_bh(&session->lock);
546 sockfd_put(sock);
547 }
548
549 static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
550 {
551 struct iscsi_conn *conn = cls_conn->dd_data;
552 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
553 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
554
555 iscsi_sw_tcp_release_conn(conn);
556
557 if (tcp_sw_conn->tx_hash.tfm)
558 crypto_free_hash(tcp_sw_conn->tx_hash.tfm);
559 if (tcp_sw_conn->rx_hash.tfm)
560 crypto_free_hash(tcp_sw_conn->rx_hash.tfm);
561
562 iscsi_tcp_conn_teardown(cls_conn);
563 }
564
565 static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
566 {
567 struct iscsi_conn *conn = cls_conn->dd_data;
568 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
569 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
570
571 /* userspace may have goofed up and not bound us */
572 if (!tcp_sw_conn->sock)
573 return;
574 /*
575 * Make sure our recv side is stopped.
576 * Older tools called conn stop before ep_disconnect
577 * so IO could still be coming in.
578 */
579 write_lock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
580 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
581 write_unlock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
582
583 iscsi_conn_stop(cls_conn, flag);
584 iscsi_sw_tcp_release_conn(conn);
585 }
586
587 static int iscsi_sw_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock,
588 char *buf, int *port,
589 int (*getname)(struct socket *,
590 struct sockaddr *,
591 int *addrlen))
592 {
593 struct sockaddr_storage *addr;
594 struct sockaddr_in6 *sin6;
595 struct sockaddr_in *sin;
596 int rc = 0, len;
597
598 addr = kmalloc(sizeof(*addr), GFP_KERNEL);
599 if (!addr)
600 return -ENOMEM;
601
602 if (getname(sock, (struct sockaddr *) addr, &len)) {
603 rc = -ENODEV;
604 goto free_addr;
605 }
606
607 switch (addr->ss_family) {
608 case AF_INET:
609 sin = (struct sockaddr_in *)addr;
610 spin_lock_bh(&conn->session->lock);
611 sprintf(buf, "%pI4", &sin->sin_addr.s_addr);
612 *port = be16_to_cpu(sin->sin_port);
613 spin_unlock_bh(&conn->session->lock);
614 break;
615 case AF_INET6:
616 sin6 = (struct sockaddr_in6 *)addr;
617 spin_lock_bh(&conn->session->lock);
618 sprintf(buf, "%pI6", &sin6->sin6_addr);
619 *port = be16_to_cpu(sin6->sin6_port);
620 spin_unlock_bh(&conn->session->lock);
621 break;
622 }
623 free_addr:
624 kfree(addr);
625 return rc;
626 }
627
628 static int
629 iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session,
630 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
631 int is_leading)
632 {
633 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
634 struct iscsi_host *ihost = shost_priv(shost);
635 struct iscsi_conn *conn = cls_conn->dd_data;
636 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
637 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
638 struct sock *sk;
639 struct socket *sock;
640 int err;
641
642 /* lookup for existing socket */
643 sock = sockfd_lookup((int)transport_eph, &err);
644 if (!sock) {
645 iscsi_conn_printk(KERN_ERR, conn,
646 "sockfd_lookup failed %d\n", err);
647 return -EEXIST;
648 }
649 /*
650 * copy these values now because if we drop the session
651 * userspace may still want to query the values since we will
652 * be using them for the reconnect
653 */
654 err = iscsi_sw_tcp_get_addr(conn, sock, conn->portal_address,
655 &conn->portal_port, kernel_getpeername);
656 if (err)
657 goto free_socket;
658
659 err = iscsi_sw_tcp_get_addr(conn, sock, ihost->local_address,
660 &ihost->local_port, kernel_getsockname);
661 if (err)
662 goto free_socket;
663
664 err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
665 if (err)
666 goto free_socket;
667
668 /* bind iSCSI connection and socket */
669 tcp_sw_conn->sock = sock;
670
671 /* setup Socket parameters */
672 sk = sock->sk;
673 sk->sk_reuse = 1;
674 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
675 sk->sk_allocation = GFP_ATOMIC;
676
677 iscsi_sw_tcp_conn_set_callbacks(conn);
678 tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage;
679 /*
680 * set receive state machine into initial state
681 */
682 iscsi_tcp_hdr_recv_prep(tcp_conn);
683 return 0;
684
685 free_socket:
686 sockfd_put(sock);
687 return err;
688 }
689
690 static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn,
691 enum iscsi_param param, char *buf,
692 int buflen)
693 {
694 struct iscsi_conn *conn = cls_conn->dd_data;
695 struct iscsi_session *session = conn->session;
696 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
697 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
698 int value;
699
700 switch(param) {
701 case ISCSI_PARAM_HDRDGST_EN:
702 iscsi_set_param(cls_conn, param, buf, buflen);
703 break;
704 case ISCSI_PARAM_DATADGST_EN:
705 iscsi_set_param(cls_conn, param, buf, buflen);
706 tcp_sw_conn->sendpage = conn->datadgst_en ?
707 sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
708 break;
709 case ISCSI_PARAM_MAX_R2T:
710 sscanf(buf, "%d", &value);
711 if (value <= 0 || !is_power_of_2(value))
712 return -EINVAL;
713 if (session->max_r2t == value)
714 break;
715 iscsi_tcp_r2tpool_free(session);
716 iscsi_set_param(cls_conn, param, buf, buflen);
717 if (iscsi_tcp_r2tpool_alloc(session))
718 return -ENOMEM;
719 break;
720 default:
721 return iscsi_set_param(cls_conn, param, buf, buflen);
722 }
723
724 return 0;
725 }
726
727 static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
728 enum iscsi_param param, char *buf)
729 {
730 struct iscsi_conn *conn = cls_conn->dd_data;
731 int len;
732
733 switch(param) {
734 case ISCSI_PARAM_CONN_PORT:
735 spin_lock_bh(&conn->session->lock);
736 len = sprintf(buf, "%hu\n", conn->portal_port);
737 spin_unlock_bh(&conn->session->lock);
738 break;
739 case ISCSI_PARAM_CONN_ADDRESS:
740 spin_lock_bh(&conn->session->lock);
741 len = sprintf(buf, "%s\n", conn->portal_address);
742 spin_unlock_bh(&conn->session->lock);
743 break;
744 default:
745 return iscsi_conn_get_param(cls_conn, param, buf);
746 }
747
748 return len;
749 }
750
751 static void
752 iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
753 struct iscsi_stats *stats)
754 {
755 struct iscsi_conn *conn = cls_conn->dd_data;
756 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
757 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
758
759 stats->custom_length = 3;
760 strcpy(stats->custom[0].desc, "tx_sendpage_failures");
761 stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt;
762 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
763 stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt;
764 strcpy(stats->custom[2].desc, "eh_abort_cnt");
765 stats->custom[2].value = conn->eh_abort_cnt;
766
767 iscsi_tcp_conn_get_stats(cls_conn, stats);
768 }
769
770 static struct iscsi_cls_session *
771 iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
772 uint16_t qdepth, uint32_t initial_cmdsn)
773 {
774 struct iscsi_cls_session *cls_session;
775 struct iscsi_session *session;
776 struct Scsi_Host *shost;
777
778 if (ep) {
779 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep);
780 return NULL;
781 }
782
783 shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, 0, 1);
784 if (!shost)
785 return NULL;
786 shost->transportt = iscsi_sw_tcp_scsi_transport;
787 shost->cmd_per_lun = qdepth;
788 shost->max_lun = iscsi_max_lun;
789 shost->max_id = 0;
790 shost->max_channel = 0;
791 shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
792
793 if (iscsi_host_add(shost, NULL))
794 goto free_host;
795
796 cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost,
797 cmds_max,
798 sizeof(struct iscsi_tcp_task) +
799 sizeof(struct iscsi_sw_tcp_hdrbuf),
800 initial_cmdsn, 0);
801 if (!cls_session)
802 goto remove_host;
803 session = cls_session->dd_data;
804
805 shost->can_queue = session->scsi_cmds_max;
806 if (iscsi_tcp_r2tpool_alloc(session))
807 goto remove_session;
808 return cls_session;
809
810 remove_session:
811 iscsi_session_teardown(cls_session);
812 remove_host:
813 iscsi_host_remove(shost);
814 free_host:
815 iscsi_host_free(shost);
816 return NULL;
817 }
818
819 static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session)
820 {
821 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
822
823 iscsi_tcp_r2tpool_free(cls_session->dd_data);
824 iscsi_session_teardown(cls_session);
825
826 iscsi_host_remove(shost);
827 iscsi_host_free(shost);
828 }
829
830 static int iscsi_sw_tcp_slave_alloc(struct scsi_device *sdev)
831 {
832 set_bit(QUEUE_FLAG_BIDI, &sdev->request_queue->queue_flags);
833 return 0;
834 }
835
836 static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev)
837 {
838 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY);
839 blk_queue_dma_alignment(sdev->request_queue, 0);
840 return 0;
841 }
842
843 static struct scsi_host_template iscsi_sw_tcp_sht = {
844 .module = THIS_MODULE,
845 .name = "iSCSI Initiator over TCP/IP",
846 .queuecommand = iscsi_queuecommand,
847 .change_queue_depth = iscsi_change_queue_depth,
848 .can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1,
849 .sg_tablesize = 4096,
850 .max_sectors = 0xFFFF,
851 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
852 .eh_abort_handler = iscsi_eh_abort,
853 .eh_device_reset_handler= iscsi_eh_device_reset,
854 .eh_target_reset_handler= iscsi_eh_target_reset,
855 .use_clustering = DISABLE_CLUSTERING,
856 .slave_alloc = iscsi_sw_tcp_slave_alloc,
857 .slave_configure = iscsi_sw_tcp_slave_configure,
858 .target_alloc = iscsi_target_alloc,
859 .proc_name = "iscsi_tcp",
860 .this_id = -1,
861 };
862
863 static struct iscsi_transport iscsi_sw_tcp_transport = {
864 .owner = THIS_MODULE,
865 .name = "tcp",
866 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
867 | CAP_DATADGST,
868 .param_mask = ISCSI_MAX_RECV_DLENGTH |
869 ISCSI_MAX_XMIT_DLENGTH |
870 ISCSI_HDRDGST_EN |
871 ISCSI_DATADGST_EN |
872 ISCSI_INITIAL_R2T_EN |
873 ISCSI_MAX_R2T |
874 ISCSI_IMM_DATA_EN |
875 ISCSI_FIRST_BURST |
876 ISCSI_MAX_BURST |
877 ISCSI_PDU_INORDER_EN |
878 ISCSI_DATASEQ_INORDER_EN |
879 ISCSI_ERL |
880 ISCSI_CONN_PORT |
881 ISCSI_CONN_ADDRESS |
882 ISCSI_EXP_STATSN |
883 ISCSI_PERSISTENT_PORT |
884 ISCSI_PERSISTENT_ADDRESS |
885 ISCSI_TARGET_NAME | ISCSI_TPGT |
886 ISCSI_USERNAME | ISCSI_PASSWORD |
887 ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN |
888 ISCSI_FAST_ABORT | ISCSI_ABORT_TMO |
889 ISCSI_LU_RESET_TMO |
890 ISCSI_PING_TMO | ISCSI_RECV_TMO |
891 ISCSI_IFACE_NAME | ISCSI_INITIATOR_NAME,
892 .host_param_mask = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
893 ISCSI_HOST_INITIATOR_NAME |
894 ISCSI_HOST_NETDEV_NAME,
895 /* session management */
896 .create_session = iscsi_sw_tcp_session_create,
897 .destroy_session = iscsi_sw_tcp_session_destroy,
898 /* connection management */
899 .create_conn = iscsi_sw_tcp_conn_create,
900 .bind_conn = iscsi_sw_tcp_conn_bind,
901 .destroy_conn = iscsi_sw_tcp_conn_destroy,
902 .set_param = iscsi_sw_tcp_conn_set_param,
903 .get_conn_param = iscsi_sw_tcp_conn_get_param,
904 .get_session_param = iscsi_session_get_param,
905 .start_conn = iscsi_conn_start,
906 .stop_conn = iscsi_sw_tcp_conn_stop,
907 /* iscsi host params */
908 .get_host_param = iscsi_host_get_param,
909 .set_host_param = iscsi_host_set_param,
910 /* IO */
911 .send_pdu = iscsi_conn_send_pdu,
912 .get_stats = iscsi_sw_tcp_conn_get_stats,
913 /* iscsi task/cmd helpers */
914 .init_task = iscsi_tcp_task_init,
915 .xmit_task = iscsi_tcp_task_xmit,
916 .cleanup_task = iscsi_tcp_cleanup_task,
917 /* low level pdu helpers */
918 .xmit_pdu = iscsi_sw_tcp_pdu_xmit,
919 .init_pdu = iscsi_sw_tcp_pdu_init,
920 .alloc_pdu = iscsi_sw_tcp_pdu_alloc,
921 /* recovery */
922 .session_recovery_timedout = iscsi_session_recovery_timedout,
923 };
924
925 static int __init iscsi_sw_tcp_init(void)
926 {
927 if (iscsi_max_lun < 1) {
928 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
929 iscsi_max_lun);
930 return -EINVAL;
931 }
932
933 iscsi_sw_tcp_scsi_transport = iscsi_register_transport(
934 &iscsi_sw_tcp_transport);
935 if (!iscsi_sw_tcp_scsi_transport)
936 return -ENODEV;
937
938 return 0;
939 }
940
941 static void __exit iscsi_sw_tcp_exit(void)
942 {
943 iscsi_unregister_transport(&iscsi_sw_tcp_transport);
944 }
945
946 module_init(iscsi_sw_tcp_init);
947 module_exit(iscsi_sw_tcp_exit);
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