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treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / scsi / iscsi_tcp.c
blobb5dd1caae5e92d03f050bdc427985f24c41917a0
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * iSCSI Initiator over TCP/IP Data-Path
4 *
5 * Copyright (C) 2004 Dmitry Yusupov
6 * Copyright (C) 2004 Alex Aizman
7 * Copyright (C) 2005 - 2006 Mike Christie
8 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
9 * maintained by open-iscsi@googlegroups.com
10 *
11 * See the file COPYING included with this distribution for more details.
12 *
13 * Credits:
14 * Christoph Hellwig
15 * FUJITA Tomonori
16 * Arne Redlich
17 * Zhenyu Wang
18 */
19
20 #include <crypto/hash.h>
21 #include <linux/types.h>
22 #include <linux/inet.h>
23 #include <linux/slab.h>
24 #include <linux/sched/mm.h>
25 #include <linux/file.h>
26 #include <linux/blkdev.h>
27 #include <linux/delay.h>
28 #include <linux/kfifo.h>
29 #include <linux/scatterlist.h>
30 #include <linux/module.h>
31 #include <linux/backing-dev.h>
32 #include <net/tcp.h>
33 #include <scsi/scsi_cmnd.h>
34 #include <scsi/scsi_device.h>
35 #include <scsi/scsi_host.h>
36 #include <scsi/scsi.h>
37 #include <scsi/scsi_transport_iscsi.h>
38 #include <trace/events/iscsi.h>
39
40 #include "iscsi_tcp.h"
41
42 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
43 "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
44 "Alex Aizman <itn780@yahoo.com>");
45 MODULE_DESCRIPTION("iSCSI/TCP data-path");
46 MODULE_LICENSE("GPL");
47
48 static struct scsi_transport_template *iscsi_sw_tcp_scsi_transport;
49 static struct scsi_host_template iscsi_sw_tcp_sht;
50 static struct iscsi_transport iscsi_sw_tcp_transport;
51
52 static unsigned int iscsi_max_lun = ~0;
53 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
54
55 static int iscsi_sw_tcp_dbg;
56 module_param_named(debug_iscsi_tcp, iscsi_sw_tcp_dbg, int,
57 S_IRUGO | S_IWUSR);
58 MODULE_PARM_DESC(debug_iscsi_tcp, "Turn on debugging for iscsi_tcp module "
59 "Set to 1 to turn on, and zero to turn off. Default is off.");
60
61 #define ISCSI_SW_TCP_DBG(_conn, dbg_fmt, arg...) \
62 do { \
63 if (iscsi_sw_tcp_dbg) \
64 iscsi_conn_printk(KERN_INFO, _conn, \
65 "%s " dbg_fmt, \
66 __func__, ##arg); \
67 iscsi_dbg_trace(trace_iscsi_dbg_sw_tcp, \
68 &(_conn)->cls_conn->dev, \
69 "%s " dbg_fmt, __func__, ##arg);\
70 } while (0);
71
72
73 /**
74 * iscsi_sw_tcp_recv - TCP receive in sendfile fashion
75 * @rd_desc: read descriptor
76 * @skb: socket buffer
77 * @offset: offset in skb
78 * @len: skb->len - offset
79 */
80 static int iscsi_sw_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
81 unsigned int offset, size_t len)
82 {
83 struct iscsi_conn *conn = rd_desc->arg.data;
84 unsigned int consumed, total_consumed = 0;
85 int status;
86
87 ISCSI_SW_TCP_DBG(conn, "in %d bytes\n", skb->len - offset);
88
89 do {
90 status = 0;
91 consumed = iscsi_tcp_recv_skb(conn, skb, offset, 0, &status);
92 offset += consumed;
93 total_consumed += consumed;
94 } while (consumed != 0 && status != ISCSI_TCP_SKB_DONE);
95
96 ISCSI_SW_TCP_DBG(conn, "read %d bytes status %d\n",
97 skb->len - offset, status);
98 return total_consumed;
99 }
100
101 /**
102 * iscsi_sw_sk_state_check - check socket state
103 * @sk: socket
104 *
105 * If the socket is in CLOSE or CLOSE_WAIT we should
106 * not close the connection if there is still some
107 * data pending.
108 *
109 * Must be called with sk_callback_lock.
110 */
111 static inline int iscsi_sw_sk_state_check(struct sock *sk)
112 {
113 struct iscsi_conn *conn = sk->sk_user_data;
114
115 if ((sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) &&
116 (conn->session->state != ISCSI_STATE_LOGGING_OUT) &&
117 !atomic_read(&sk->sk_rmem_alloc)) {
118 ISCSI_SW_TCP_DBG(conn, "TCP_CLOSE|TCP_CLOSE_WAIT\n");
119 iscsi_conn_failure(conn, ISCSI_ERR_TCP_CONN_CLOSE);
120 return -ECONNRESET;
121 }
122 return 0;
123 }
124
125 static void iscsi_sw_tcp_data_ready(struct sock *sk)
126 {
127 struct iscsi_conn *conn;
128 struct iscsi_tcp_conn *tcp_conn;
129 read_descriptor_t rd_desc;
130
131 read_lock_bh(&sk->sk_callback_lock);
132 conn = sk->sk_user_data;
133 if (!conn) {
134 read_unlock_bh(&sk->sk_callback_lock);
135 return;
136 }
137 tcp_conn = conn->dd_data;
138
139 /*
140 * Use rd_desc to pass 'conn' to iscsi_tcp_recv.
141 * We set count to 1 because we want the network layer to
142 * hand us all the skbs that are available. iscsi_tcp_recv
143 * handled pdus that cross buffers or pdus that still need data.
144 */
145 rd_desc.arg.data = conn;
146 rd_desc.count = 1;
147 tcp_read_sock(sk, &rd_desc, iscsi_sw_tcp_recv);
148
149 iscsi_sw_sk_state_check(sk);
150
151 /* If we had to (atomically) map a highmem page,
152 * unmap it now. */
153 iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
154 read_unlock_bh(&sk->sk_callback_lock);
155 }
156
157 static void iscsi_sw_tcp_state_change(struct sock *sk)
158 {
159 struct iscsi_tcp_conn *tcp_conn;
160 struct iscsi_sw_tcp_conn *tcp_sw_conn;
161 struct iscsi_conn *conn;
162 void (*old_state_change)(struct sock *);
163
164 read_lock_bh(&sk->sk_callback_lock);
165 conn = sk->sk_user_data;
166 if (!conn) {
167 read_unlock_bh(&sk->sk_callback_lock);
168 return;
169 }
170
171 iscsi_sw_sk_state_check(sk);
172
173 tcp_conn = conn->dd_data;
174 tcp_sw_conn = tcp_conn->dd_data;
175 old_state_change = tcp_sw_conn->old_state_change;
176
177 read_unlock_bh(&sk->sk_callback_lock);
178
179 old_state_change(sk);
180 }
181
182 /**
183 * iscsi_write_space - Called when more output buffer space is available
184 * @sk: socket space is available for
185 **/
186 static void iscsi_sw_tcp_write_space(struct sock *sk)
187 {
188 struct iscsi_conn *conn;
189 struct iscsi_tcp_conn *tcp_conn;
190 struct iscsi_sw_tcp_conn *tcp_sw_conn;
191 void (*old_write_space)(struct sock *);
192
193 read_lock_bh(&sk->sk_callback_lock);
194 conn = sk->sk_user_data;
195 if (!conn) {
196 read_unlock_bh(&sk->sk_callback_lock);
197 return;
198 }
199
200 tcp_conn = conn->dd_data;
201 tcp_sw_conn = tcp_conn->dd_data;
202 old_write_space = tcp_sw_conn->old_write_space;
203 read_unlock_bh(&sk->sk_callback_lock);
204
205 old_write_space(sk);
206
207 ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n");
208 iscsi_conn_queue_work(conn);
209 }
210
211 static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn)
212 {
213 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
214 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
215 struct sock *sk = tcp_sw_conn->sock->sk;
216
217 /* assign new callbacks */
218 write_lock_bh(&sk->sk_callback_lock);
219 sk->sk_user_data = conn;
220 tcp_sw_conn->old_data_ready = sk->sk_data_ready;
221 tcp_sw_conn->old_state_change = sk->sk_state_change;
222 tcp_sw_conn->old_write_space = sk->sk_write_space;
223 sk->sk_data_ready = iscsi_sw_tcp_data_ready;
224 sk->sk_state_change = iscsi_sw_tcp_state_change;
225 sk->sk_write_space = iscsi_sw_tcp_write_space;
226 write_unlock_bh(&sk->sk_callback_lock);
227 }
228
229 static void
230 iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_conn *conn)
231 {
232 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
233 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
234 struct sock *sk = tcp_sw_conn->sock->sk;
235
236 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
237 write_lock_bh(&sk->sk_callback_lock);
238 sk->sk_user_data = NULL;
239 sk->sk_data_ready = tcp_sw_conn->old_data_ready;
240 sk->sk_state_change = tcp_sw_conn->old_state_change;
241 sk->sk_write_space = tcp_sw_conn->old_write_space;
242 sk->sk_no_check_tx = 0;
243 write_unlock_bh(&sk->sk_callback_lock);
244 }
245
246 /**
247 * iscsi_sw_tcp_xmit_segment - transmit segment
248 * @tcp_conn: the iSCSI TCP connection
249 * @segment: the buffer to transmnit
250 *
251 * This function transmits as much of the buffer as
252 * the network layer will accept, and returns the number of
253 * bytes transmitted.
254 *
255 * If CRC hashing is enabled, the function will compute the
256 * hash as it goes. When the entire segment has been transmitted,
257 * it will retrieve the hash value and send it as well.
258 */
259 static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
260 struct iscsi_segment *segment)
261 {
262 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
263 struct socket *sk = tcp_sw_conn->sock;
264 unsigned int copied = 0;
265 int r = 0;
266
267 while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) {
268 struct scatterlist *sg;
269 unsigned int offset, copy;
270 int flags = 0;
271
272 r = 0;
273 offset = segment->copied;
274 copy = segment->size - offset;
275
276 if (segment->total_copied + segment->size < segment->total_size)
277 flags |= MSG_MORE;
278
279 /* Use sendpage if we can; else fall back to sendmsg */
280 if (!segment->data) {
281 sg = segment->sg;
282 offset += segment->sg_offset + sg->offset;
283 r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset,
284 copy, flags);
285 } else {
286 struct msghdr msg = { .msg_flags = flags };
287 struct kvec iov = {
288 .iov_base = segment->data + offset,
289 .iov_len = copy
290 };
291
292 r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
293 }
294
295 if (r < 0) {
296 iscsi_tcp_segment_unmap(segment);
297 return r;
298 }
299 copied += r;
300 }
301 return copied;
302 }
303
304 /**
305 * iscsi_sw_tcp_xmit - TCP transmit
306 * @conn: iscsi connection
307 **/
308 static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn)
309 {
310 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
311 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
312 struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
313 unsigned int consumed = 0;
314 int rc = 0;
315
316 while (1) {
317 rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment);
318 /*
319 * We may not have been able to send data because the conn
320 * is getting stopped. libiscsi will know so propagate err
321 * for it to do the right thing.
322 */
323 if (rc == -EAGAIN)
324 return rc;
325 else if (rc < 0) {
326 rc = ISCSI_ERR_XMIT_FAILED;
327 goto error;
328 } else if (rc == 0)
329 break;
330
331 consumed += rc;
332
333 if (segment->total_copied >= segment->total_size) {
334 if (segment->done != NULL) {
335 rc = segment->done(tcp_conn, segment);
336 if (rc != 0)
337 goto error;
338 }
339 }
340 }
341
342 ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed);
343
344 conn->txdata_octets += consumed;
345 return consumed;
346
347 error:
348 /* Transmit error. We could initiate error recovery
349 * here. */
350 ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc);
351 iscsi_conn_failure(conn, rc);
352 return -EIO;
353 }
354
355 /**
356 * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit
357 * @conn: iscsi connection
358 */
359 static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn)
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 struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
364
365 return segment->total_copied - segment->total_size;
366 }
367
368 static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task)
369 {
370 struct iscsi_conn *conn = task->conn;
371 unsigned int noreclaim_flag;
372 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
373 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
374 int rc = 0;
375
376 if (!tcp_sw_conn->sock) {
377 iscsi_conn_printk(KERN_ERR, conn,
378 "Transport not bound to socket!\n");
379 return -EINVAL;
380 }
381
382 noreclaim_flag = memalloc_noreclaim_save();
383
384 while (iscsi_sw_tcp_xmit_qlen(conn)) {
385 rc = iscsi_sw_tcp_xmit(conn);
386 if (rc == 0) {
387 rc = -EAGAIN;
388 break;
389 }
390 if (rc < 0)
391 break;
392 rc = 0;
393 }
394
395 memalloc_noreclaim_restore(noreclaim_flag);
396 return rc;
397 }
398
399 /*
400 * This is called when we're done sending the header.
401 * Simply copy the data_segment to the send segment, and return.
402 */
403 static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
404 struct iscsi_segment *segment)
405 {
406 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
407
408 tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment;
409 ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn,
410 "Header done. Next segment size %u total_size %u\n",
411 tcp_sw_conn->out.segment.size,
412 tcp_sw_conn->out.segment.total_size);
413 return 0;
414 }
415
416 static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr,
417 size_t hdrlen)
418 {
419 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
420 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
421
422 ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ?
423 "digest enabled" : "digest disabled");
424
425 /* Clear the data segment - needs to be filled in by the
426 * caller using iscsi_tcp_send_data_prep() */
427 memset(&tcp_sw_conn->out.data_segment, 0,
428 sizeof(struct iscsi_segment));
429
430 /* If header digest is enabled, compute the CRC and
431 * place the digest into the same buffer. We make
432 * sure that both iscsi_tcp_task and mtask have
433 * sufficient room.
434 */
435 if (conn->hdrdgst_en) {
436 iscsi_tcp_dgst_header(tcp_sw_conn->tx_hash, hdr, hdrlen,
437 hdr + hdrlen);
438 hdrlen += ISCSI_DIGEST_SIZE;
439 }
440
441 /* Remember header pointer for later, when we need
442 * to decide whether there's a payload to go along
443 * with the header. */
444 tcp_sw_conn->out.hdr = hdr;
445
446 iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen,
447 iscsi_sw_tcp_send_hdr_done, NULL);
448 }
449
450 /*
451 * Prepare the send buffer for the payload data.
452 * Padding and checksumming will all be taken care
453 * of by the iscsi_segment routines.
454 */
455 static int
456 iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
457 unsigned int count, unsigned int offset,
458 unsigned int len)
459 {
460 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
461 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
462 struct ahash_request *tx_hash = NULL;
463 unsigned int hdr_spec_len;
464
465 ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len,
466 conn->datadgst_en ?
467 "digest enabled" : "digest disabled");
468
469 /* Make sure the datalen matches what the caller
470 said he would send. */
471 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
472 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
473
474 if (conn->datadgst_en)
475 tx_hash = tcp_sw_conn->tx_hash;
476
477 return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment,
478 sg, count, offset, len,
479 NULL, tx_hash);
480 }
481
482 static void
483 iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data,
484 size_t len)
485 {
486 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
487 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
488 struct ahash_request *tx_hash = NULL;
489 unsigned int hdr_spec_len;
490
491 ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ?
492 "digest enabled" : "digest disabled");
493
494 /* Make sure the datalen matches what the caller
495 said he would send. */
496 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
497 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
498
499 if (conn->datadgst_en)
500 tx_hash = tcp_sw_conn->tx_hash;
501
502 iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment,
503 data, len, NULL, tx_hash);
504 }
505
506 static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task,
507 unsigned int offset, unsigned int count)
508 {
509 struct iscsi_conn *conn = task->conn;
510 int err = 0;
511
512 iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
513
514 if (!count)
515 return 0;
516
517 if (!task->sc)
518 iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count);
519 else {
520 struct scsi_data_buffer *sdb = &task->sc->sdb;
521
522 err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl,
523 sdb->table.nents, offset,
524 count);
525 }
526
527 if (err) {
528 /* got invalid offset/len */
529 return -EIO;
530 }
531 return 0;
532 }
533
534 static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
535 {
536 struct iscsi_tcp_task *tcp_task = task->dd_data;
537
538 task->hdr = task->dd_data + sizeof(*tcp_task);
539 task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE;
540 return 0;
541 }
542
543 static struct iscsi_cls_conn *
544 iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session,
545 uint32_t conn_idx)
546 {
547 struct iscsi_conn *conn;
548 struct iscsi_cls_conn *cls_conn;
549 struct iscsi_tcp_conn *tcp_conn;
550 struct iscsi_sw_tcp_conn *tcp_sw_conn;
551 struct crypto_ahash *tfm;
552
553 cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn),
554 conn_idx);
555 if (!cls_conn)
556 return NULL;
557 conn = cls_conn->dd_data;
558 tcp_conn = conn->dd_data;
559 tcp_sw_conn = tcp_conn->dd_data;
560
561 tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC);
562 if (IS_ERR(tfm))
563 goto free_conn;
564
565 tcp_sw_conn->tx_hash = ahash_request_alloc(tfm, GFP_KERNEL);
566 if (!tcp_sw_conn->tx_hash)
567 goto free_tfm;
568 ahash_request_set_callback(tcp_sw_conn->tx_hash, 0, NULL, NULL);
569
570 tcp_sw_conn->rx_hash = ahash_request_alloc(tfm, GFP_KERNEL);
571 if (!tcp_sw_conn->rx_hash)
572 goto free_tx_hash;
573 ahash_request_set_callback(tcp_sw_conn->rx_hash, 0, NULL, NULL);
574
575 tcp_conn->rx_hash = tcp_sw_conn->rx_hash;
576
577 return cls_conn;
578
579 free_tx_hash:
580 ahash_request_free(tcp_sw_conn->tx_hash);
581 free_tfm:
582 crypto_free_ahash(tfm);
583 free_conn:
584 iscsi_conn_printk(KERN_ERR, conn,
585 "Could not create connection due to crc32c "
586 "loading error. Make sure the crc32c "
587 "module is built as a module or into the "
588 "kernel\n");
589 iscsi_tcp_conn_teardown(cls_conn);
590 return NULL;
591 }
592
593 static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn)
594 {
595 struct iscsi_session *session = conn->session;
596 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
597 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
598 struct socket *sock = tcp_sw_conn->sock;
599
600 if (!sock)
601 return;
602
603 sock_hold(sock->sk);
604 iscsi_sw_tcp_conn_restore_callbacks(conn);
605 sock_put(sock->sk);
606
607 spin_lock_bh(&session->frwd_lock);
608 tcp_sw_conn->sock = NULL;
609 spin_unlock_bh(&session->frwd_lock);
610 sockfd_put(sock);
611 }
612
613 static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
614 {
615 struct iscsi_conn *conn = cls_conn->dd_data;
616 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
617 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
618
619 iscsi_sw_tcp_release_conn(conn);
620
621 ahash_request_free(tcp_sw_conn->rx_hash);
622 if (tcp_sw_conn->tx_hash) {
623 struct crypto_ahash *tfm;
624
625 tfm = crypto_ahash_reqtfm(tcp_sw_conn->tx_hash);
626 ahash_request_free(tcp_sw_conn->tx_hash);
627 crypto_free_ahash(tfm);
628 }
629
630 iscsi_tcp_conn_teardown(cls_conn);
631 }
632
633 static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
634 {
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 socket *sock = tcp_sw_conn->sock;
639
640 /* userspace may have goofed up and not bound us */
641 if (!sock)
642 return;
643
644 sock->sk->sk_err = EIO;
645 wake_up_interruptible(sk_sleep(sock->sk));
646
647 /* stop xmit side */
648 iscsi_suspend_tx(conn);
649
650 /* stop recv side and release socket */
651 iscsi_sw_tcp_release_conn(conn);
652
653 iscsi_conn_stop(cls_conn, flag);
654 }
655
656 static int
657 iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session,
658 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
659 int is_leading)
660 {
661 struct iscsi_session *session = cls_session->dd_data;
662 struct iscsi_conn *conn = cls_conn->dd_data;
663 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
664 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
665 struct sock *sk;
666 struct socket *sock;
667 int err;
668
669 /* lookup for existing socket */
670 sock = sockfd_lookup((int)transport_eph, &err);
671 if (!sock) {
672 iscsi_conn_printk(KERN_ERR, conn,
673 "sockfd_lookup failed %d\n", err);
674 return -EEXIST;
675 }
676
677 err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
678 if (err)
679 goto free_socket;
680
681 spin_lock_bh(&session->frwd_lock);
682 /* bind iSCSI connection and socket */
683 tcp_sw_conn->sock = sock;
684 spin_unlock_bh(&session->frwd_lock);
685
686 /* setup Socket parameters */
687 sk = sock->sk;
688 sk->sk_reuse = SK_CAN_REUSE;
689 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
690 sk->sk_allocation = GFP_ATOMIC;
691 sk_set_memalloc(sk);
692
693 iscsi_sw_tcp_conn_set_callbacks(conn);
694 tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage;
695 /*
696 * set receive state machine into initial state
697 */
698 iscsi_tcp_hdr_recv_prep(tcp_conn);
699 return 0;
700
701 free_socket:
702 sockfd_put(sock);
703 return err;
704 }
705
706 static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn,
707 enum iscsi_param param, char *buf,
708 int buflen)
709 {
710 struct iscsi_conn *conn = cls_conn->dd_data;
711 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
712 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
713
714 switch(param) {
715 case ISCSI_PARAM_HDRDGST_EN:
716 iscsi_set_param(cls_conn, param, buf, buflen);
717 break;
718 case ISCSI_PARAM_DATADGST_EN:
719 iscsi_set_param(cls_conn, param, buf, buflen);
720 tcp_sw_conn->sendpage = conn->datadgst_en ?
721 sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
722 break;
723 case ISCSI_PARAM_MAX_R2T:
724 return iscsi_tcp_set_max_r2t(conn, buf);
725 default:
726 return iscsi_set_param(cls_conn, param, buf, buflen);
727 }
728
729 return 0;
730 }
731
732 static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
733 enum iscsi_param param, char *buf)
734 {
735 struct iscsi_conn *conn = cls_conn->dd_data;
736 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
737 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
738 struct sockaddr_in6 addr;
739 int rc;
740
741 switch(param) {
742 case ISCSI_PARAM_CONN_PORT:
743 case ISCSI_PARAM_CONN_ADDRESS:
744 case ISCSI_PARAM_LOCAL_PORT:
745 spin_lock_bh(&conn->session->frwd_lock);
746 if (!tcp_sw_conn || !tcp_sw_conn->sock) {
747 spin_unlock_bh(&conn->session->frwd_lock);
748 return -ENOTCONN;
749 }
750 if (param == ISCSI_PARAM_LOCAL_PORT)
751 rc = kernel_getsockname(tcp_sw_conn->sock,
752 (struct sockaddr *)&addr);
753 else
754 rc = kernel_getpeername(tcp_sw_conn->sock,
755 (struct sockaddr *)&addr);
756 spin_unlock_bh(&conn->session->frwd_lock);
757 if (rc < 0)
758 return rc;
759
760 return iscsi_conn_get_addr_param((struct sockaddr_storage *)
761 &addr, param, buf);
762 default:
763 return iscsi_conn_get_param(cls_conn, param, buf);
764 }
765
766 return 0;
767 }
768
769 static int iscsi_sw_tcp_host_get_param(struct Scsi_Host *shost,
770 enum iscsi_host_param param, char *buf)
771 {
772 struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(shost);
773 struct iscsi_session *session = tcp_sw_host->session;
774 struct iscsi_conn *conn;
775 struct iscsi_tcp_conn *tcp_conn;
776 struct iscsi_sw_tcp_conn *tcp_sw_conn;
777 struct sockaddr_in6 addr;
778 int rc;
779
780 switch (param) {
781 case ISCSI_HOST_PARAM_IPADDRESS:
782 if (!session)
783 return -ENOTCONN;
784
785 spin_lock_bh(&session->frwd_lock);
786 conn = session->leadconn;
787 if (!conn) {
788 spin_unlock_bh(&session->frwd_lock);
789 return -ENOTCONN;
790 }
791 tcp_conn = conn->dd_data;
792
793 tcp_sw_conn = tcp_conn->dd_data;
794 if (!tcp_sw_conn->sock) {
795 spin_unlock_bh(&session->frwd_lock);
796 return -ENOTCONN;
797 }
798
799 rc = kernel_getsockname(tcp_sw_conn->sock,
800 (struct sockaddr *)&addr);
801 spin_unlock_bh(&session->frwd_lock);
802 if (rc < 0)
803 return rc;
804
805 return iscsi_conn_get_addr_param((struct sockaddr_storage *)
806 &addr,
807 (enum iscsi_param)param, buf);
808 default:
809 return iscsi_host_get_param(shost, param, buf);
810 }
811
812 return 0;
813 }
814
815 static void
816 iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
817 struct iscsi_stats *stats)
818 {
819 struct iscsi_conn *conn = cls_conn->dd_data;
820 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
821 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
822
823 stats->custom_length = 3;
824 strcpy(stats->custom[0].desc, "tx_sendpage_failures");
825 stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt;
826 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
827 stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt;
828 strcpy(stats->custom[2].desc, "eh_abort_cnt");
829 stats->custom[2].value = conn->eh_abort_cnt;
830
831 iscsi_tcp_conn_get_stats(cls_conn, stats);
832 }
833
834 static struct iscsi_cls_session *
835 iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
836 uint16_t qdepth, uint32_t initial_cmdsn)
837 {
838 struct iscsi_cls_session *cls_session;
839 struct iscsi_session *session;
840 struct iscsi_sw_tcp_host *tcp_sw_host;
841 struct Scsi_Host *shost;
842
843 if (ep) {
844 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep);
845 return NULL;
846 }
847
848 shost = iscsi_host_alloc(&iscsi_sw_tcp_sht,
849 sizeof(struct iscsi_sw_tcp_host), 1);
850 if (!shost)
851 return NULL;
852 shost->transportt = iscsi_sw_tcp_scsi_transport;
853 shost->cmd_per_lun = qdepth;
854 shost->max_lun = iscsi_max_lun;
855 shost->max_id = 0;
856 shost->max_channel = 0;
857 shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
858
859 if (iscsi_host_add(shost, NULL))
860 goto free_host;
861
862 cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost,
863 cmds_max, 0,
864 sizeof(struct iscsi_tcp_task) +
865 sizeof(struct iscsi_sw_tcp_hdrbuf),
866 initial_cmdsn, 0);
867 if (!cls_session)
868 goto remove_host;
869 session = cls_session->dd_data;
870 tcp_sw_host = iscsi_host_priv(shost);
871 tcp_sw_host->session = session;
872
873 shost->can_queue = session->scsi_cmds_max;
874 if (iscsi_tcp_r2tpool_alloc(session))
875 goto remove_session;
876 return cls_session;
877
878 remove_session:
879 iscsi_session_teardown(cls_session);
880 remove_host:
881 iscsi_host_remove(shost);
882 free_host:
883 iscsi_host_free(shost);
884 return NULL;
885 }
886
887 static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session)
888 {
889 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
890 struct iscsi_session *session = cls_session->dd_data;
891
892 if (WARN_ON_ONCE(session->leadconn))
893 return;
894
895 iscsi_tcp_r2tpool_free(cls_session->dd_data);
896 iscsi_session_teardown(cls_session);
897
898 iscsi_host_remove(shost);
899 iscsi_host_free(shost);
900 }
901
902 static umode_t iscsi_sw_tcp_attr_is_visible(int param_type, int param)
903 {
904 switch (param_type) {
905 case ISCSI_HOST_PARAM:
906 switch (param) {
907 case ISCSI_HOST_PARAM_NETDEV_NAME:
908 case ISCSI_HOST_PARAM_HWADDRESS:
909 case ISCSI_HOST_PARAM_IPADDRESS:
910 case ISCSI_HOST_PARAM_INITIATOR_NAME:
911 return S_IRUGO;
912 default:
913 return 0;
914 }
915 case ISCSI_PARAM:
916 switch (param) {
917 case ISCSI_PARAM_MAX_RECV_DLENGTH:
918 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
919 case ISCSI_PARAM_HDRDGST_EN:
920 case ISCSI_PARAM_DATADGST_EN:
921 case ISCSI_PARAM_CONN_ADDRESS:
922 case ISCSI_PARAM_CONN_PORT:
923 case ISCSI_PARAM_LOCAL_PORT:
924 case ISCSI_PARAM_EXP_STATSN:
925 case ISCSI_PARAM_PERSISTENT_ADDRESS:
926 case ISCSI_PARAM_PERSISTENT_PORT:
927 case ISCSI_PARAM_PING_TMO:
928 case ISCSI_PARAM_RECV_TMO:
929 case ISCSI_PARAM_INITIAL_R2T_EN:
930 case ISCSI_PARAM_MAX_R2T:
931 case ISCSI_PARAM_IMM_DATA_EN:
932 case ISCSI_PARAM_FIRST_BURST:
933 case ISCSI_PARAM_MAX_BURST:
934 case ISCSI_PARAM_PDU_INORDER_EN:
935 case ISCSI_PARAM_DATASEQ_INORDER_EN:
936 case ISCSI_PARAM_ERL:
937 case ISCSI_PARAM_TARGET_NAME:
938 case ISCSI_PARAM_TPGT:
939 case ISCSI_PARAM_USERNAME:
940 case ISCSI_PARAM_PASSWORD:
941 case ISCSI_PARAM_USERNAME_IN:
942 case ISCSI_PARAM_PASSWORD_IN:
943 case ISCSI_PARAM_FAST_ABORT:
944 case ISCSI_PARAM_ABORT_TMO:
945 case ISCSI_PARAM_LU_RESET_TMO:
946 case ISCSI_PARAM_TGT_RESET_TMO:
947 case ISCSI_PARAM_IFACE_NAME:
948 case ISCSI_PARAM_INITIATOR_NAME:
949 return S_IRUGO;
950 default:
951 return 0;
952 }
953 }
954
955 return 0;
956 }
957
958 static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev)
959 {
960 struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(sdev->host);
961 struct iscsi_session *session = tcp_sw_host->session;
962 struct iscsi_conn *conn = session->leadconn;
963
964 if (conn->datadgst_en)
965 sdev->request_queue->backing_dev_info->capabilities
966 |= BDI_CAP_STABLE_WRITES;
967 blk_queue_dma_alignment(sdev->request_queue, 0);
968 return 0;
969 }
970
971 static struct scsi_host_template iscsi_sw_tcp_sht = {
972 .module = THIS_MODULE,
973 .name = "iSCSI Initiator over TCP/IP",
974 .queuecommand = iscsi_queuecommand,
975 .change_queue_depth = scsi_change_queue_depth,
976 .can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1,
977 .sg_tablesize = 4096,
978 .max_sectors = 0xFFFF,
979 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
980 .eh_timed_out = iscsi_eh_cmd_timed_out,
981 .eh_abort_handler = iscsi_eh_abort,
982 .eh_device_reset_handler= iscsi_eh_device_reset,
983 .eh_target_reset_handler = iscsi_eh_recover_target,
984 .dma_boundary = PAGE_SIZE - 1,
985 .slave_configure = iscsi_sw_tcp_slave_configure,
986 .target_alloc = iscsi_target_alloc,
987 .proc_name = "iscsi_tcp",
988 .this_id = -1,
989 .track_queue_depth = 1,
990 };
991
992 static struct iscsi_transport iscsi_sw_tcp_transport = {
993 .owner = THIS_MODULE,
994 .name = "tcp",
995 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
996 | CAP_DATADGST,
997 /* session management */
998 .create_session = iscsi_sw_tcp_session_create,
999 .destroy_session = iscsi_sw_tcp_session_destroy,
1000 /* connection management */
1001 .create_conn = iscsi_sw_tcp_conn_create,
1002 .bind_conn = iscsi_sw_tcp_conn_bind,
1003 .destroy_conn = iscsi_sw_tcp_conn_destroy,
1004 .attr_is_visible = iscsi_sw_tcp_attr_is_visible,
1005 .set_param = iscsi_sw_tcp_conn_set_param,
1006 .get_conn_param = iscsi_sw_tcp_conn_get_param,
1007 .get_session_param = iscsi_session_get_param,
1008 .start_conn = iscsi_conn_start,
1009 .stop_conn = iscsi_sw_tcp_conn_stop,
1010 /* iscsi host params */
1011 .get_host_param = iscsi_sw_tcp_host_get_param,
1012 .set_host_param = iscsi_host_set_param,
1013 /* IO */
1014 .send_pdu = iscsi_conn_send_pdu,
1015 .get_stats = iscsi_sw_tcp_conn_get_stats,
1016 /* iscsi task/cmd helpers */
1017 .init_task = iscsi_tcp_task_init,
1018 .xmit_task = iscsi_tcp_task_xmit,
1019 .cleanup_task = iscsi_tcp_cleanup_task,
1020 /* low level pdu helpers */
1021 .xmit_pdu = iscsi_sw_tcp_pdu_xmit,
1022 .init_pdu = iscsi_sw_tcp_pdu_init,
1023 .alloc_pdu = iscsi_sw_tcp_pdu_alloc,
1024 /* recovery */
1025 .session_recovery_timedout = iscsi_session_recovery_timedout,
1026 };
1027
1028 static int __init iscsi_sw_tcp_init(void)
1029 {
1030 if (iscsi_max_lun < 1) {
1031 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
1032 iscsi_max_lun);
1033 return -EINVAL;
1034 }
1035
1036 iscsi_sw_tcp_scsi_transport = iscsi_register_transport(
1037 &iscsi_sw_tcp_transport);
1038 if (!iscsi_sw_tcp_scsi_transport)
1039 return -ENODEV;
1040
1041 return 0;
1042 }
1043
1044 static void __exit iscsi_sw_tcp_exit(void)
1045 {
1046 iscsi_unregister_transport(&iscsi_sw_tcp_transport);
1047 }
1048
1049 module_init(iscsi_sw_tcp_init);
1050 module_exit(iscsi_sw_tcp_exit);
Linux with added FPC-III support