[SCSI] iscsi_tcp: don't fire conn error if pdu init fails
[linux-2.6.git] / drivers / scsi / iscsi_tcp.c
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                         if (copied || r == -EAGAIN)
257                                 break;
258                         return r;
259                 }
260                 copied += r;
261         }
262         return copied;
263 }
264
265 /**
266  * iscsi_sw_tcp_xmit - TCP transmit
267  **/
268 static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn)
269 {
270         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
271         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
272         struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
273         unsigned int consumed = 0;
274         int rc = 0;
275
276         while (1) {
277                 rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment);
278                 if (rc < 0) {
279                         rc = ISCSI_ERR_XMIT_FAILED;
280                         goto error;
281                 }
282                 if (rc == 0)
283                         break;
284
285                 consumed += rc;
286
287                 if (segment->total_copied >= segment->total_size) {
288                         if (segment->done != NULL) {
289                                 rc = segment->done(tcp_conn, segment);
290                                 if (rc != 0)
291                                         goto error;
292                         }
293                 }
294         }
295
296         ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed);
297
298         conn->txdata_octets += consumed;
299         return consumed;
300
301 error:
302         /* Transmit error. We could initiate error recovery
303          * here. */
304         ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc);
305         iscsi_conn_failure(conn, rc);
306         return -EIO;
307 }
308
309 /**
310  * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit
311  */
312 static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn)
313 {
314         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
315         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
316         struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
317
318         return segment->total_copied - segment->total_size;
319 }
320
321 static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task)
322 {
323         struct iscsi_conn *conn = task->conn;
324         int rc;
325
326         while (iscsi_sw_tcp_xmit_qlen(conn)) {
327                 rc = iscsi_sw_tcp_xmit(conn);
328                 if (rc == 0)
329                         return -EAGAIN;
330                 if (rc < 0)
331                         return rc;
332         }
333
334         return 0;
335 }
336
337 /*
338  * This is called when we're done sending the header.
339  * Simply copy the data_segment to the send segment, and return.
340  */
341 static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
342                                       struct iscsi_segment *segment)
343 {
344         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
345
346         tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment;
347         ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn,
348                          "Header done. Next segment size %u total_size %u\n",
349                          tcp_sw_conn->out.segment.size,
350                          tcp_sw_conn->out.segment.total_size);
351         return 0;
352 }
353
354 static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr,
355                                        size_t hdrlen)
356 {
357         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
358         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
359
360         ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ?
361                          "digest enabled" : "digest disabled");
362
363         /* Clear the data segment - needs to be filled in by the
364          * caller using iscsi_tcp_send_data_prep() */
365         memset(&tcp_sw_conn->out.data_segment, 0,
366                sizeof(struct iscsi_segment));
367
368         /* If header digest is enabled, compute the CRC and
369          * place the digest into the same buffer. We make
370          * sure that both iscsi_tcp_task and mtask have
371          * sufficient room.
372          */
373         if (conn->hdrdgst_en) {
374                 iscsi_tcp_dgst_header(&tcp_sw_conn->tx_hash, hdr, hdrlen,
375                                       hdr + hdrlen);
376                 hdrlen += ISCSI_DIGEST_SIZE;
377         }
378
379         /* Remember header pointer for later, when we need
380          * to decide whether there's a payload to go along
381          * with the header. */
382         tcp_sw_conn->out.hdr = hdr;
383
384         iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen,
385                                   iscsi_sw_tcp_send_hdr_done, NULL);
386 }
387
388 /*
389  * Prepare the send buffer for the payload data.
390  * Padding and checksumming will all be taken care
391  * of by the iscsi_segment routines.
392  */
393 static int
394 iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
395                             unsigned int count, unsigned int offset,
396                             unsigned int len)
397 {
398         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
399         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
400         struct hash_desc *tx_hash = NULL;
401         unsigned int hdr_spec_len;
402
403         ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len,
404                          conn->datadgst_en ?
405                          "digest enabled" : "digest disabled");
406
407         /* Make sure the datalen matches what the caller
408            said he would send. */
409         hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
410         WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
411
412         if (conn->datadgst_en)
413                 tx_hash = &tcp_sw_conn->tx_hash;
414
415         return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment,
416                                      sg, count, offset, len,
417                                      NULL, tx_hash);
418 }
419
420 static void
421 iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data,
422                                    size_t len)
423 {
424         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
425         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
426         struct hash_desc *tx_hash = NULL;
427         unsigned int hdr_spec_len;
428
429         ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ?
430                          "digest enabled" : "digest disabled");
431
432         /* Make sure the datalen matches what the caller
433            said he would send. */
434         hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
435         WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
436
437         if (conn->datadgst_en)
438                 tx_hash = &tcp_sw_conn->tx_hash;
439
440         iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment,
441                                 data, len, NULL, tx_hash);
442 }
443
444 static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task,
445                                  unsigned int offset, unsigned int count)
446 {
447         struct iscsi_conn *conn = task->conn;
448         int err = 0;
449
450         iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
451
452         if (!count)
453                 return 0;
454
455         if (!task->sc)
456                 iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count);
457         else {
458                 struct scsi_data_buffer *sdb = scsi_out(task->sc);
459
460                 err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl,
461                                                   sdb->table.nents, offset,
462                                                   count);
463         }
464
465         if (err) {
466                 /* got invalid offset/len */
467                 return -EIO;
468         }
469         return 0;
470 }
471
472 static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
473 {
474         struct iscsi_tcp_task *tcp_task = task->dd_data;
475
476         task->hdr = task->dd_data + sizeof(*tcp_task);
477         task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE;
478         return 0;
479 }
480
481 static struct iscsi_cls_conn *
482 iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session,
483                          uint32_t conn_idx)
484 {
485         struct iscsi_conn *conn;
486         struct iscsi_cls_conn *cls_conn;
487         struct iscsi_tcp_conn *tcp_conn;
488         struct iscsi_sw_tcp_conn *tcp_sw_conn;
489
490         cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn),
491                                         conn_idx);
492         if (!cls_conn)
493                 return NULL;
494         conn = cls_conn->dd_data;
495         tcp_conn = conn->dd_data;
496         tcp_sw_conn = tcp_conn->dd_data;
497
498         tcp_sw_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0,
499                                                      CRYPTO_ALG_ASYNC);
500         tcp_sw_conn->tx_hash.flags = 0;
501         if (IS_ERR(tcp_sw_conn->tx_hash.tfm))
502                 goto free_conn;
503
504         tcp_sw_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0,
505                                                      CRYPTO_ALG_ASYNC);
506         tcp_sw_conn->rx_hash.flags = 0;
507         if (IS_ERR(tcp_sw_conn->rx_hash.tfm))
508                 goto free_tx_tfm;
509         tcp_conn->rx_hash = &tcp_sw_conn->rx_hash;
510
511         return cls_conn;
512
513 free_tx_tfm:
514         crypto_free_hash(tcp_sw_conn->tx_hash.tfm);
515 free_conn:
516         iscsi_conn_printk(KERN_ERR, conn,
517                           "Could not create connection due to crc32c "
518                           "loading error. Make sure the crc32c "
519                           "module is built as a module or into the "
520                           "kernel\n");
521         iscsi_tcp_conn_teardown(cls_conn);
522         return NULL;
523 }
524
525 static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn)
526 {
527         struct iscsi_session *session = conn->session;
528         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
529         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
530         struct socket *sock = tcp_sw_conn->sock;
531
532         if (!sock)
533                 return;
534
535         sock_hold(sock->sk);
536         iscsi_sw_tcp_conn_restore_callbacks(tcp_sw_conn);
537         sock_put(sock->sk);
538
539         spin_lock_bh(&session->lock);
540         tcp_sw_conn->sock = NULL;
541         spin_unlock_bh(&session->lock);
542         sockfd_put(sock);
543 }
544
545 static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
546 {
547         struct iscsi_conn *conn = cls_conn->dd_data;
548         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
549         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
550
551         iscsi_sw_tcp_release_conn(conn);
552
553         if (tcp_sw_conn->tx_hash.tfm)
554                 crypto_free_hash(tcp_sw_conn->tx_hash.tfm);
555         if (tcp_sw_conn->rx_hash.tfm)
556                 crypto_free_hash(tcp_sw_conn->rx_hash.tfm);
557
558         iscsi_tcp_conn_teardown(cls_conn);
559 }
560
561 static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
562 {
563         struct iscsi_conn *conn = cls_conn->dd_data;
564         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
565         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
566
567         /* userspace may have goofed up and not bound us */
568         if (!tcp_sw_conn->sock)
569                 return;
570         /*
571          * Make sure our recv side is stopped.
572          * Older tools called conn stop before ep_disconnect
573          * so IO could still be coming in.
574          */
575         write_lock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
576         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
577         write_unlock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
578
579         iscsi_conn_stop(cls_conn, flag);
580         iscsi_sw_tcp_release_conn(conn);
581 }
582
583 static int iscsi_sw_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock,
584                                  char *buf, int *port,
585                                  int (*getname)(struct socket *,
586                                                 struct sockaddr *,
587                                                 int *addrlen))
588 {
589         struct sockaddr_storage *addr;
590         struct sockaddr_in6 *sin6;
591         struct sockaddr_in *sin;
592         int rc = 0, len;
593
594         addr = kmalloc(sizeof(*addr), GFP_KERNEL);
595         if (!addr)
596                 return -ENOMEM;
597
598         if (getname(sock, (struct sockaddr *) addr, &len)) {
599                 rc = -ENODEV;
600                 goto free_addr;
601         }
602
603         switch (addr->ss_family) {
604         case AF_INET:
605                 sin = (struct sockaddr_in *)addr;
606                 spin_lock_bh(&conn->session->lock);
607                 sprintf(buf, "%pI4", &sin->sin_addr.s_addr);
608                 *port = be16_to_cpu(sin->sin_port);
609                 spin_unlock_bh(&conn->session->lock);
610                 break;
611         case AF_INET6:
612                 sin6 = (struct sockaddr_in6 *)addr;
613                 spin_lock_bh(&conn->session->lock);
614                 sprintf(buf, "%pI6", &sin6->sin6_addr);
615                 *port = be16_to_cpu(sin6->sin6_port);
616                 spin_unlock_bh(&conn->session->lock);
617                 break;
618         }
619 free_addr:
620         kfree(addr);
621         return rc;
622 }
623
624 static int
625 iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session,
626                        struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
627                        int is_leading)
628 {
629         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
630         struct iscsi_host *ihost = shost_priv(shost);
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 sock *sk;
635         struct socket *sock;
636         int err;
637
638         /* lookup for existing socket */
639         sock = sockfd_lookup((int)transport_eph, &err);
640         if (!sock) {
641                 iscsi_conn_printk(KERN_ERR, conn,
642                                   "sockfd_lookup failed %d\n", err);
643                 return -EEXIST;
644         }
645         /*
646          * copy these values now because if we drop the session
647          * userspace may still want to query the values since we will
648          * be using them for the reconnect
649          */
650         err = iscsi_sw_tcp_get_addr(conn, sock, conn->portal_address,
651                                     &conn->portal_port, kernel_getpeername);
652         if (err)
653                 goto free_socket;
654
655         err = iscsi_sw_tcp_get_addr(conn, sock, ihost->local_address,
656                                     &ihost->local_port, kernel_getsockname);
657         if (err)
658                 goto free_socket;
659
660         err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
661         if (err)
662                 goto free_socket;
663
664         /* bind iSCSI connection and socket */
665         tcp_sw_conn->sock = sock;
666
667         /* setup Socket parameters */
668         sk = sock->sk;
669         sk->sk_reuse = 1;
670         sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
671         sk->sk_allocation = GFP_ATOMIC;
672
673         iscsi_sw_tcp_conn_set_callbacks(conn);
674         tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage;
675         /*
676          * set receive state machine into initial state
677          */
678         iscsi_tcp_hdr_recv_prep(tcp_conn);
679         return 0;
680
681 free_socket:
682         sockfd_put(sock);
683         return err;
684 }
685
686 static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn,
687                                        enum iscsi_param param, char *buf,
688                                        int buflen)
689 {
690         struct iscsi_conn *conn = cls_conn->dd_data;
691         struct iscsi_session *session = conn->session;
692         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
693         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
694         int value;
695
696         switch(param) {
697         case ISCSI_PARAM_HDRDGST_EN:
698                 iscsi_set_param(cls_conn, param, buf, buflen);
699                 break;
700         case ISCSI_PARAM_DATADGST_EN:
701                 iscsi_set_param(cls_conn, param, buf, buflen);
702                 tcp_sw_conn->sendpage = conn->datadgst_en ?
703                         sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
704                 break;
705         case ISCSI_PARAM_MAX_R2T:
706                 sscanf(buf, "%d", &value);
707                 if (value <= 0 || !is_power_of_2(value))
708                         return -EINVAL;
709                 if (session->max_r2t == value)
710                         break;
711                 iscsi_tcp_r2tpool_free(session);
712                 iscsi_set_param(cls_conn, param, buf, buflen);
713                 if (iscsi_tcp_r2tpool_alloc(session))
714                         return -ENOMEM;
715                 break;
716         default:
717                 return iscsi_set_param(cls_conn, param, buf, buflen);
718         }
719
720         return 0;
721 }
722
723 static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
724                                        enum iscsi_param param, char *buf)
725 {
726         struct iscsi_conn *conn = cls_conn->dd_data;
727         int len;
728
729         switch(param) {
730         case ISCSI_PARAM_CONN_PORT:
731                 spin_lock_bh(&conn->session->lock);
732                 len = sprintf(buf, "%hu\n", conn->portal_port);
733                 spin_unlock_bh(&conn->session->lock);
734                 break;
735         case ISCSI_PARAM_CONN_ADDRESS:
736                 spin_lock_bh(&conn->session->lock);
737                 len = sprintf(buf, "%s\n", conn->portal_address);
738                 spin_unlock_bh(&conn->session->lock);
739                 break;
740         default:
741                 return iscsi_conn_get_param(cls_conn, param, buf);
742         }
743
744         return len;
745 }
746
747 static void
748 iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
749                             struct iscsi_stats *stats)
750 {
751         struct iscsi_conn *conn = cls_conn->dd_data;
752         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
753         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
754
755         stats->custom_length = 3;
756         strcpy(stats->custom[0].desc, "tx_sendpage_failures");
757         stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt;
758         strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
759         stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt;
760         strcpy(stats->custom[2].desc, "eh_abort_cnt");
761         stats->custom[2].value = conn->eh_abort_cnt;
762
763         iscsi_tcp_conn_get_stats(cls_conn, stats);
764 }
765
766 static struct iscsi_cls_session *
767 iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
768                             uint16_t qdepth, uint32_t initial_cmdsn)
769 {
770         struct iscsi_cls_session *cls_session;
771         struct iscsi_session *session;
772         struct Scsi_Host *shost;
773
774         if (ep) {
775                 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep);
776                 return NULL;
777         }
778
779         shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, 0, 1);
780         if (!shost)
781                 return NULL;
782         shost->transportt = iscsi_sw_tcp_scsi_transport;
783         shost->cmd_per_lun = qdepth;
784         shost->max_lun = iscsi_max_lun;
785         shost->max_id = 0;
786         shost->max_channel = 0;
787         shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
788
789         if (iscsi_host_add(shost, NULL))
790                 goto free_host;
791
792         cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost,
793                                           cmds_max,
794                                           sizeof(struct iscsi_tcp_task) +
795                                           sizeof(struct iscsi_sw_tcp_hdrbuf),
796                                           initial_cmdsn, 0);
797         if (!cls_session)
798                 goto remove_host;
799         session = cls_session->dd_data;
800
801         shost->can_queue = session->scsi_cmds_max;
802         if (iscsi_tcp_r2tpool_alloc(session))
803                 goto remove_session;
804         return cls_session;
805
806 remove_session:
807         iscsi_session_teardown(cls_session);
808 remove_host:
809         iscsi_host_remove(shost);
810 free_host:
811         iscsi_host_free(shost);
812         return NULL;
813 }
814
815 static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session)
816 {
817         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
818
819         iscsi_tcp_r2tpool_free(cls_session->dd_data);
820         iscsi_session_teardown(cls_session);
821
822         iscsi_host_remove(shost);
823         iscsi_host_free(shost);
824 }
825
826 static int iscsi_sw_tcp_slave_alloc(struct scsi_device *sdev)
827 {
828         set_bit(QUEUE_FLAG_BIDI, &sdev->request_queue->queue_flags);
829         return 0;
830 }
831
832 static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev)
833 {
834         blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY);
835         blk_queue_dma_alignment(sdev->request_queue, 0);
836         return 0;
837 }
838
839 static struct scsi_host_template iscsi_sw_tcp_sht = {
840         .module                 = THIS_MODULE,
841         .name                   = "iSCSI Initiator over TCP/IP",
842         .queuecommand           = iscsi_queuecommand,
843         .change_queue_depth     = iscsi_change_queue_depth,
844         .can_queue              = ISCSI_DEF_XMIT_CMDS_MAX - 1,
845         .sg_tablesize           = 4096,
846         .max_sectors            = 0xFFFF,
847         .cmd_per_lun            = ISCSI_DEF_CMD_PER_LUN,
848         .eh_abort_handler       = iscsi_eh_abort,
849         .eh_device_reset_handler= iscsi_eh_device_reset,
850         .eh_target_reset_handler= iscsi_eh_target_reset,
851         .use_clustering         = DISABLE_CLUSTERING,
852         .slave_alloc            = iscsi_sw_tcp_slave_alloc,
853         .slave_configure        = iscsi_sw_tcp_slave_configure,
854         .proc_name              = "iscsi_tcp",
855         .this_id                = -1,
856 };
857
858 static struct iscsi_transport iscsi_sw_tcp_transport = {
859         .owner                  = THIS_MODULE,
860         .name                   = "tcp",
861         .caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
862                                   | CAP_DATADGST,
863         .param_mask             = ISCSI_MAX_RECV_DLENGTH |
864                                   ISCSI_MAX_XMIT_DLENGTH |
865                                   ISCSI_HDRDGST_EN |
866                                   ISCSI_DATADGST_EN |
867                                   ISCSI_INITIAL_R2T_EN |
868                                   ISCSI_MAX_R2T |
869                                   ISCSI_IMM_DATA_EN |
870                                   ISCSI_FIRST_BURST |
871                                   ISCSI_MAX_BURST |
872                                   ISCSI_PDU_INORDER_EN |
873                                   ISCSI_DATASEQ_INORDER_EN |
874                                   ISCSI_ERL |
875                                   ISCSI_CONN_PORT |
876                                   ISCSI_CONN_ADDRESS |
877                                   ISCSI_EXP_STATSN |
878                                   ISCSI_PERSISTENT_PORT |
879                                   ISCSI_PERSISTENT_ADDRESS |
880                                   ISCSI_TARGET_NAME | ISCSI_TPGT |
881                                   ISCSI_USERNAME | ISCSI_PASSWORD |
882                                   ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN |
883                                   ISCSI_FAST_ABORT | ISCSI_ABORT_TMO |
884                                   ISCSI_LU_RESET_TMO |
885                                   ISCSI_PING_TMO | ISCSI_RECV_TMO |
886                                   ISCSI_IFACE_NAME | ISCSI_INITIATOR_NAME,
887         .host_param_mask        = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
888                                   ISCSI_HOST_INITIATOR_NAME |
889                                   ISCSI_HOST_NETDEV_NAME,
890         /* session management */
891         .create_session         = iscsi_sw_tcp_session_create,
892         .destroy_session        = iscsi_sw_tcp_session_destroy,
893         /* connection management */
894         .create_conn            = iscsi_sw_tcp_conn_create,
895         .bind_conn              = iscsi_sw_tcp_conn_bind,
896         .destroy_conn           = iscsi_sw_tcp_conn_destroy,
897         .set_param              = iscsi_sw_tcp_conn_set_param,
898         .get_conn_param         = iscsi_sw_tcp_conn_get_param,
899         .get_session_param      = iscsi_session_get_param,
900         .start_conn             = iscsi_conn_start,
901         .stop_conn              = iscsi_sw_tcp_conn_stop,
902         /* iscsi host params */
903         .get_host_param         = iscsi_host_get_param,
904         .set_host_param         = iscsi_host_set_param,
905         /* IO */
906         .send_pdu               = iscsi_conn_send_pdu,
907         .get_stats              = iscsi_sw_tcp_conn_get_stats,
908         /* iscsi task/cmd helpers */
909         .init_task              = iscsi_tcp_task_init,
910         .xmit_task              = iscsi_tcp_task_xmit,
911         .cleanup_task           = iscsi_tcp_cleanup_task,
912         /* low level pdu helpers */
913         .xmit_pdu               = iscsi_sw_tcp_pdu_xmit,
914         .init_pdu               = iscsi_sw_tcp_pdu_init,
915         .alloc_pdu              = iscsi_sw_tcp_pdu_alloc,
916         /* recovery */
917         .session_recovery_timedout = iscsi_session_recovery_timedout,
918 };
919
920 static int __init iscsi_sw_tcp_init(void)
921 {
922         if (iscsi_max_lun < 1) {
923                 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
924                        iscsi_max_lun);
925                 return -EINVAL;
926         }
927
928         iscsi_sw_tcp_scsi_transport = iscsi_register_transport(
929                                                 &iscsi_sw_tcp_transport);
930         if (!iscsi_sw_tcp_scsi_transport)
931                 return -ENODEV;
932
933         return 0;
934 }
935
936 static void __exit iscsi_sw_tcp_exit(void)
937 {
938         iscsi_unregister_transport(&iscsi_sw_tcp_transport);
939 }
940
941 module_init(iscsi_sw_tcp_init);
942 module_exit(iscsi_sw_tcp_exit);