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Alex Aizman7ba24712005-08-04 19:30:08 -07001/*
2 * iSCSI Initiator over TCP/IP Data-Path
3 *
4 * Copyright (C) 2004 Dmitry Yusupov
5 * Copyright (C) 2004 Alex Aizman
Mike Christie5bb0b552006-04-06 21:26:46 -05006 * Copyright (C) 2005 - 2006 Mike Christie
7 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
Alex Aizman7ba24712005-08-04 19:30:08 -07008 * 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/list.h>
31#include <linux/inet.h>
Mike Christie4e7aba72007-05-30 12:57:23 -050032#include <linux/file.h>
Alex Aizman7ba24712005-08-04 19:30:08 -070033#include <linux/blkdev.h>
34#include <linux/crypto.h>
35#include <linux/delay.h>
36#include <linux/kfifo.h>
37#include <linux/scatterlist.h>
38#include <net/tcp.h>
39#include <scsi/scsi_cmnd.h>
Mike Christied1d81c02007-05-30 12:57:21 -050040#include <scsi/scsi_device.h>
Alex Aizman7ba24712005-08-04 19:30:08 -070041#include <scsi/scsi_host.h>
42#include <scsi/scsi.h>
43#include <scsi/scsi_transport_iscsi.h>
44
45#include "iscsi_tcp.h"
46
47MODULE_AUTHOR("Dmitry Yusupov <dmitry_yus@yahoo.com>, "
48 "Alex Aizman <itn780@yahoo.com>");
49MODULE_DESCRIPTION("iSCSI/TCP data-path");
50MODULE_LICENSE("GPL");
Olaf Kirchda32dd62007-12-13 12:43:21 -060051#undef DEBUG_TCP
Alex Aizman7ba24712005-08-04 19:30:08 -070052#define DEBUG_ASSERT
53
54#ifdef DEBUG_TCP
Mike Christie5bb0b552006-04-06 21:26:46 -050055#define debug_tcp(fmt...) printk(KERN_INFO "tcp: " fmt)
Alex Aizman7ba24712005-08-04 19:30:08 -070056#else
57#define debug_tcp(fmt...)
58#endif
59
Alex Aizman7ba24712005-08-04 19:30:08 -070060#ifndef DEBUG_ASSERT
61#ifdef BUG_ON
62#undef BUG_ON
63#endif
64#define BUG_ON(expr)
65#endif
66
Alex Aizman7ba24712005-08-04 19:30:08 -070067static unsigned int iscsi_max_lun = 512;
68module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
69
Olaf Kirchda32dd62007-12-13 12:43:21 -060070static int iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
Olaf Kircha8ac6312007-12-13 12:43:35 -060071 struct iscsi_segment *segment);
Alex Aizman7ba24712005-08-04 19:30:08 -070072
Olaf Kirchda32dd62007-12-13 12:43:21 -060073/*
Olaf Kircha8ac6312007-12-13 12:43:35 -060074 * Scatterlist handling: inside the iscsi_segment, we
Olaf Kirchda32dd62007-12-13 12:43:21 -060075 * remember an index into the scatterlist, and set data/size
76 * to the current scatterlist entry. For highmem pages, we
77 * kmap as needed.
78 *
79 * Note that the page is unmapped when we return from
80 * TCP's data_ready handler, so we may end up mapping and
81 * unmapping the same page repeatedly. The whole reason
82 * for this is that we shouldn't keep the page mapped
83 * outside the softirq.
84 */
85
86/**
Olaf Kircha8ac6312007-12-13 12:43:35 -060087 * iscsi_tcp_segment_init_sg - init indicated scatterlist entry
88 * @segment: the buffer object
89 * @sg: scatterlist
Olaf Kirchda32dd62007-12-13 12:43:21 -060090 * @offset: byte offset into that sg entry
91 *
Olaf Kircha8ac6312007-12-13 12:43:35 -060092 * This function sets up the segment so that subsequent
Olaf Kirchda32dd62007-12-13 12:43:21 -060093 * data is copied to the indicated sg entry, at the given
94 * offset.
95 */
96static inline void
Olaf Kircha8ac6312007-12-13 12:43:35 -060097iscsi_tcp_segment_init_sg(struct iscsi_segment *segment,
98 struct scatterlist *sg, unsigned int offset)
Alex Aizman7ba24712005-08-04 19:30:08 -070099{
Olaf Kircha8ac6312007-12-13 12:43:35 -0600100 segment->sg = sg;
101 segment->sg_offset = offset;
102 segment->size = min(sg->length - offset,
103 segment->total_size - segment->total_copied);
104 segment->data = NULL;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600105}
Alex Aizman7ba24712005-08-04 19:30:08 -0700106
Olaf Kirchda32dd62007-12-13 12:43:21 -0600107/**
Olaf Kircha8ac6312007-12-13 12:43:35 -0600108 * iscsi_tcp_segment_map - map the current S/G page
109 * @segment: iscsi_segment
110 * @recv: 1 if called from recv path
Olaf Kirchda32dd62007-12-13 12:43:21 -0600111 *
112 * We only need to possibly kmap data if scatter lists are being used,
113 * because the iscsi passthrough and internal IO paths will never use high
114 * mem pages.
115 */
116static inline void
Olaf Kircha8ac6312007-12-13 12:43:35 -0600117iscsi_tcp_segment_map(struct iscsi_segment *segment, int recv)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600118{
119 struct scatterlist *sg;
Alex Aizman7ba24712005-08-04 19:30:08 -0700120
Olaf Kircha8ac6312007-12-13 12:43:35 -0600121 if (segment->data != NULL || !segment->sg)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600122 return;
Alex Aizman7ba24712005-08-04 19:30:08 -0700123
Olaf Kircha8ac6312007-12-13 12:43:35 -0600124 sg = segment->sg;
125 BUG_ON(segment->sg_mapped);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600126 BUG_ON(sg->length == 0);
Olaf Kircha8ac6312007-12-13 12:43:35 -0600127
128 /*
129 * If the page count is greater than one it is ok to send
130 * to the network layer's zero copy send path. If not we
131 * have to go the slow sendmsg path. We always map for the
132 * recv path.
133 */
134 if (page_count(sg_page(sg)) >= 1 && !recv)
135 return;
136
137 debug_tcp("iscsi_tcp_segment_map %s %p\n", recv ? "recv" : "xmit",
138 segment);
139 segment->sg_mapped = kmap_atomic(sg_page(sg), KM_SOFTIRQ0);
140 segment->data = segment->sg_mapped + sg->offset + segment->sg_offset;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600141}
Alex Aizman7ba24712005-08-04 19:30:08 -0700142
Olaf Kirchda32dd62007-12-13 12:43:21 -0600143static inline void
Olaf Kircha8ac6312007-12-13 12:43:35 -0600144iscsi_tcp_segment_unmap(struct iscsi_segment *segment)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600145{
Olaf Kircha8ac6312007-12-13 12:43:35 -0600146 debug_tcp("iscsi_tcp_segment_unmap %p\n", segment);
147
148 if (segment->sg_mapped) {
149 debug_tcp("iscsi_tcp_segment_unmap valid\n");
150 kunmap_atomic(segment->sg_mapped, KM_SOFTIRQ0);
151 segment->sg_mapped = NULL;
152 segment->data = NULL;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600153 }
154}
Alex Aizman7ba24712005-08-04 19:30:08 -0700155
Olaf Kirchda32dd62007-12-13 12:43:21 -0600156/*
157 * Splice the digest buffer into the buffer
158 */
159static inline void
Olaf Kircha8ac6312007-12-13 12:43:35 -0600160iscsi_tcp_segment_splice_digest(struct iscsi_segment *segment, void *digest)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600161{
Olaf Kircha8ac6312007-12-13 12:43:35 -0600162 segment->data = digest;
163 segment->digest_len = ISCSI_DIGEST_SIZE;
164 segment->total_size += ISCSI_DIGEST_SIZE;
165 segment->size = ISCSI_DIGEST_SIZE;
166 segment->copied = 0;
167 segment->sg = NULL;
168 segment->hash = NULL;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600169}
Alex Aizman7ba24712005-08-04 19:30:08 -0700170
Olaf Kirchda32dd62007-12-13 12:43:21 -0600171/**
Olaf Kircha8ac6312007-12-13 12:43:35 -0600172 * iscsi_tcp_segment_done - check whether the segment is complete
173 * @segment: iscsi segment to check
174 * @recv: set to one of this is called from the recv path
175 * @copied: number of bytes copied
Olaf Kirchda32dd62007-12-13 12:43:21 -0600176 *
Olaf Kircha8ac6312007-12-13 12:43:35 -0600177 * Check if we're done receiving this segment. If the receive
Olaf Kirchda32dd62007-12-13 12:43:21 -0600178 * buffer is full but we expect more data, move on to the
179 * next entry in the scatterlist.
180 *
181 * If the amount of data we received isn't a multiple of 4,
182 * we will transparently receive the pad bytes, too.
183 *
184 * This function must be re-entrant.
185 */
186static inline int
Olaf Kircha8ac6312007-12-13 12:43:35 -0600187iscsi_tcp_segment_done(struct iscsi_segment *segment, int recv, unsigned copied)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600188{
189 static unsigned char padbuf[ISCSI_PAD_LEN];
Olaf Kircha8ac6312007-12-13 12:43:35 -0600190 struct scatterlist sg;
Boaz Harrosh004d6532007-12-13 12:43:23 -0600191 unsigned int pad;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600192
Olaf Kircha8ac6312007-12-13 12:43:35 -0600193 debug_tcp("copied %u %u size %u %s\n", segment->copied, copied,
194 segment->size, recv ? "recv" : "xmit");
195 if (segment->hash && copied) {
196 /*
197 * If a segment is kmapd we must unmap it before sending
198 * to the crypto layer since that will try to kmap it again.
199 */
200 iscsi_tcp_segment_unmap(segment);
201
202 if (!segment->data) {
203 sg_init_table(&sg, 1);
204 sg_set_page(&sg, sg_page(segment->sg), copied,
205 segment->copied + segment->sg_offset +
206 segment->sg->offset);
207 } else
208 sg_init_one(&sg, segment->data + segment->copied,
209 copied);
210 crypto_hash_update(segment->hash, &sg, copied);
211 }
212
213 segment->copied += copied;
214 if (segment->copied < segment->size) {
215 iscsi_tcp_segment_map(segment, recv);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600216 return 0;
Alex Aizman7ba24712005-08-04 19:30:08 -0700217 }
218
Olaf Kircha8ac6312007-12-13 12:43:35 -0600219 segment->total_copied += segment->copied;
220 segment->copied = 0;
221 segment->size = 0;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600222
223 /* Unmap the current scatterlist page, if there is one. */
Olaf Kircha8ac6312007-12-13 12:43:35 -0600224 iscsi_tcp_segment_unmap(segment);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600225
226 /* Do we have more scatterlist entries? */
Olaf Kircha8ac6312007-12-13 12:43:35 -0600227 debug_tcp("total copied %u total size %u\n", segment->total_copied,
228 segment->total_size);
229 if (segment->total_copied < segment->total_size) {
Olaf Kirchda32dd62007-12-13 12:43:21 -0600230 /* Proceed to the next entry in the scatterlist. */
Olaf Kircha8ac6312007-12-13 12:43:35 -0600231 iscsi_tcp_segment_init_sg(segment, sg_next(segment->sg),
232 0);
233 iscsi_tcp_segment_map(segment, recv);
234 BUG_ON(segment->size == 0);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600235 return 0;
236 }
237
238 /* Do we need to handle padding? */
Olaf Kircha8ac6312007-12-13 12:43:35 -0600239 pad = iscsi_padding(segment->total_copied);
Boaz Harrosh004d6532007-12-13 12:43:23 -0600240 if (pad != 0) {
Olaf Kirchda32dd62007-12-13 12:43:21 -0600241 debug_tcp("consume %d pad bytes\n", pad);
Olaf Kircha8ac6312007-12-13 12:43:35 -0600242 segment->total_size += pad;
243 segment->size = pad;
244 segment->data = padbuf;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600245 return 0;
246 }
247
248 /*
Olaf Kircha8ac6312007-12-13 12:43:35 -0600249 * Set us up for transferring the data digest. hdr digest
Olaf Kirchda32dd62007-12-13 12:43:21 -0600250 * is completely handled in hdr done function.
251 */
Olaf Kircha8ac6312007-12-13 12:43:35 -0600252 if (segment->hash) {
253 crypto_hash_final(segment->hash, segment->digest);
254 iscsi_tcp_segment_splice_digest(segment,
255 recv ? segment->recv_digest : segment->digest);
256 return 0;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600257 }
258
259 return 1;
260}
261
262/**
Olaf Kircha8ac6312007-12-13 12:43:35 -0600263 * iscsi_tcp_xmit_segment - transmit segment
Olaf Kirchda32dd62007-12-13 12:43:21 -0600264 * @tcp_conn: the iSCSI TCP connection
Olaf Kircha8ac6312007-12-13 12:43:35 -0600265 * @segment: the buffer to transmnit
266 *
267 * This function transmits as much of the buffer as
268 * the network layer will accept, and returns the number of
269 * bytes transmitted.
270 *
271 * If CRC hashing is enabled, the function will compute the
272 * hash as it goes. When the entire segment has been transmitted,
273 * it will retrieve the hash value and send it as well.
274 */
275static int
276iscsi_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
277 struct iscsi_segment *segment)
278{
279 struct socket *sk = tcp_conn->sock;
280 unsigned int copied = 0;
281 int r = 0;
282
283 while (!iscsi_tcp_segment_done(segment, 0, r)) {
284 struct scatterlist *sg;
285 unsigned int offset, copy;
286 int flags = 0;
287
288 r = 0;
289 offset = segment->copied;
290 copy = segment->size - offset;
291
292 if (segment->total_copied + segment->size < segment->total_size)
293 flags |= MSG_MORE;
294
295 /* Use sendpage if we can; else fall back to sendmsg */
296 if (!segment->data) {
297 sg = segment->sg;
298 offset += segment->sg_offset + sg->offset;
299 r = tcp_conn->sendpage(sk, sg_page(sg), offset, copy,
300 flags);
301 } else {
302 struct msghdr msg = { .msg_flags = flags };
303 struct kvec iov = {
304 .iov_base = segment->data + offset,
305 .iov_len = copy
306 };
307
308 r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
309 }
310
311 if (r < 0) {
312 iscsi_tcp_segment_unmap(segment);
313 if (copied || r == -EAGAIN)
314 break;
315 return r;
316 }
317 copied += r;
318 }
319 return copied;
320}
321
322/**
323 * iscsi_tcp_segment_recv - copy data to segment
324 * @tcp_conn: the iSCSI TCP connection
325 * @segment: the buffer to copy to
Olaf Kirchda32dd62007-12-13 12:43:21 -0600326 * @ptr: data pointer
327 * @len: amount of data available
328 *
329 * This function copies up to @len bytes to the
330 * given buffer, and returns the number of bytes
331 * consumed, which can actually be less than @len.
332 *
333 * If hash digest is enabled, the function will update the
334 * hash while copying.
335 * Combining these two operations doesn't buy us a lot (yet),
336 * but in the future we could implement combined copy+crc,
337 * just way we do for network layer checksums.
338 */
339static int
Olaf Kircha8ac6312007-12-13 12:43:35 -0600340iscsi_tcp_segment_recv(struct iscsi_tcp_conn *tcp_conn,
341 struct iscsi_segment *segment, const void *ptr,
342 unsigned int len)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600343{
Olaf Kircha8ac6312007-12-13 12:43:35 -0600344 unsigned int copy = 0, copied = 0;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600345
Olaf Kircha8ac6312007-12-13 12:43:35 -0600346 while (!iscsi_tcp_segment_done(segment, 1, copy)) {
347 if (copied == len) {
348 debug_tcp("iscsi_tcp_segment_recv copied %d bytes\n",
349 len);
350 break;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600351 }
Olaf Kircha8ac6312007-12-13 12:43:35 -0600352
353 copy = min(len - copied, segment->size - segment->copied);
354 debug_tcp("iscsi_tcp_segment_recv copying %d\n", copy);
355 memcpy(segment->data + segment->copied, ptr + copied, copy);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600356 copied += copy;
357 }
Olaf Kirchda32dd62007-12-13 12:43:21 -0600358 return copied;
359}
360
361static inline void
362iscsi_tcp_dgst_header(struct hash_desc *hash, const void *hdr, size_t hdrlen,
363 unsigned char digest[ISCSI_DIGEST_SIZE])
364{
365 struct scatterlist sg;
366
367 sg_init_one(&sg, hdr, hdrlen);
368 crypto_hash_digest(hash, &sg, hdrlen, digest);
369}
370
371static inline int
372iscsi_tcp_dgst_verify(struct iscsi_tcp_conn *tcp_conn,
Olaf Kircha8ac6312007-12-13 12:43:35 -0600373 struct iscsi_segment *segment)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600374{
Olaf Kircha8ac6312007-12-13 12:43:35 -0600375 if (!segment->digest_len)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600376 return 1;
377
Olaf Kircha8ac6312007-12-13 12:43:35 -0600378 if (memcmp(segment->recv_digest, segment->digest,
379 segment->digest_len)) {
Olaf Kirchda32dd62007-12-13 12:43:21 -0600380 debug_scsi("digest mismatch\n");
381 return 0;
382 }
383
384 return 1;
385}
386
387/*
Olaf Kircha8ac6312007-12-13 12:43:35 -0600388 * Helper function to set up segment buffer
Olaf Kirchda32dd62007-12-13 12:43:21 -0600389 */
390static inline void
Olaf Kircha8ac6312007-12-13 12:43:35 -0600391__iscsi_segment_init(struct iscsi_segment *segment, size_t size,
392 iscsi_segment_done_fn_t *done, struct hash_desc *hash)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600393{
Olaf Kircha8ac6312007-12-13 12:43:35 -0600394 memset(segment, 0, sizeof(*segment));
395 segment->total_size = size;
396 segment->done = done;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600397
398 if (hash) {
Olaf Kircha8ac6312007-12-13 12:43:35 -0600399 segment->hash = hash;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600400 crypto_hash_init(hash);
401 }
402}
403
404static inline void
Olaf Kircha8ac6312007-12-13 12:43:35 -0600405iscsi_segment_init_linear(struct iscsi_segment *segment, void *data,
406 size_t size, iscsi_segment_done_fn_t *done,
407 struct hash_desc *hash)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600408{
Olaf Kircha8ac6312007-12-13 12:43:35 -0600409 __iscsi_segment_init(segment, size, done, hash);
410 segment->data = data;
411 segment->size = size;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600412}
413
414static inline int
Olaf Kircha8ac6312007-12-13 12:43:35 -0600415iscsi_segment_seek_sg(struct iscsi_segment *segment,
416 struct scatterlist *sg_list, unsigned int sg_count,
417 unsigned int offset, size_t size,
418 iscsi_segment_done_fn_t *done, struct hash_desc *hash)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600419{
Olaf Kircha8ac6312007-12-13 12:43:35 -0600420 struct scatterlist *sg;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600421 unsigned int i;
422
Olaf Kircha8ac6312007-12-13 12:43:35 -0600423 debug_scsi("iscsi_segment_seek_sg offset %u size %llu\n",
424 offset, size);
425 __iscsi_segment_init(segment, size, done, hash);
426 for_each_sg(sg_list, sg, sg_count, i) {
427 debug_scsi("sg %d, len %u offset %u\n", i, sg->length,
428 sg->offset);
429 if (offset < sg->length) {
430 iscsi_tcp_segment_init_sg(segment, sg, offset);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600431 return 0;
432 }
Olaf Kircha8ac6312007-12-13 12:43:35 -0600433 offset -= sg->length;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600434 }
435
436 return ISCSI_ERR_DATA_OFFSET;
437}
438
439/**
Olaf Kircha8ac6312007-12-13 12:43:35 -0600440 * iscsi_tcp_hdr_recv_prep - prep segment for hdr reception
Olaf Kirchda32dd62007-12-13 12:43:21 -0600441 * @tcp_conn: iscsi connection to prep for
442 *
443 * This function always passes NULL for the hash argument, because when this
444 * function is called we do not yet know the final size of the header and want
445 * to delay the digest processing until we know that.
446 */
447static void
448iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn)
449{
450 debug_tcp("iscsi_tcp_hdr_recv_prep(%p%s)\n", tcp_conn,
451 tcp_conn->iscsi_conn->hdrdgst_en ? ", digest enabled" : "");
Olaf Kircha8ac6312007-12-13 12:43:35 -0600452 iscsi_segment_init_linear(&tcp_conn->in.segment,
Olaf Kirchda32dd62007-12-13 12:43:21 -0600453 tcp_conn->in.hdr_buf, sizeof(struct iscsi_hdr),
454 iscsi_tcp_hdr_recv_done, NULL);
455}
456
457/*
458 * Handle incoming reply to any other type of command
459 */
460static int
461iscsi_tcp_data_recv_done(struct iscsi_tcp_conn *tcp_conn,
Olaf Kircha8ac6312007-12-13 12:43:35 -0600462 struct iscsi_segment *segment)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600463{
464 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
465 int rc = 0;
466
Olaf Kircha8ac6312007-12-13 12:43:35 -0600467 if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
Olaf Kirchda32dd62007-12-13 12:43:21 -0600468 return ISCSI_ERR_DATA_DGST;
469
470 rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr,
471 conn->data, tcp_conn->in.datalen);
472 if (rc)
473 return rc;
474
475 iscsi_tcp_hdr_recv_prep(tcp_conn);
Alex Aizman7ba24712005-08-04 19:30:08 -0700476 return 0;
477}
478
Olaf Kirchda32dd62007-12-13 12:43:21 -0600479static void
480iscsi_tcp_data_recv_prep(struct iscsi_tcp_conn *tcp_conn)
481{
482 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
483 struct hash_desc *rx_hash = NULL;
484
485 if (conn->datadgst_en)
486 rx_hash = &tcp_conn->rx_hash;
487
Olaf Kircha8ac6312007-12-13 12:43:35 -0600488 iscsi_segment_init_linear(&tcp_conn->in.segment,
Olaf Kirchda32dd62007-12-13 12:43:21 -0600489 conn->data, tcp_conn->in.datalen,
490 iscsi_tcp_data_recv_done, rx_hash);
491}
492
Mike Christie30a6c652006-04-06 21:13:39 -0500493/*
494 * must be called with session lock
495 */
496static void
Mike Christieb6c395e2006-07-24 15:47:15 -0500497iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
Alex Aizman7ba24712005-08-04 19:30:08 -0700498{
Mike Christie5bb0b552006-04-06 21:26:46 -0500499 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
Mike Christieb6c395e2006-07-24 15:47:15 -0500500 struct iscsi_r2t_info *r2t;
Alex Aizman7ba24712005-08-04 19:30:08 -0700501
Mike Christieb6c395e2006-07-24 15:47:15 -0500502 /* flush ctask's r2t queues */
503 while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
504 __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
505 sizeof(void*));
506 debug_scsi("iscsi_tcp_cleanup_ctask pending r2t dropped\n");
507 }
508
Olaf Kircha8ac6312007-12-13 12:43:35 -0600509 r2t = tcp_ctask->r2t;
510 if (r2t != NULL) {
511 __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
512 sizeof(void*));
513 tcp_ctask->r2t = NULL;
514 }
Alex Aizman7ba24712005-08-04 19:30:08 -0700515}
516
517/**
518 * iscsi_data_rsp - SCSI Data-In Response processing
519 * @conn: iscsi connection
520 * @ctask: scsi command task
521 **/
522static int
523iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
524{
Mike Christie5bb0b552006-04-06 21:26:46 -0500525 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
526 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
527 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)tcp_conn->in.hdr;
Alex Aizman7ba24712005-08-04 19:30:08 -0700528 struct iscsi_session *session = conn->session;
Mike Christie857ae0b2007-05-30 12:57:15 -0500529 struct scsi_cmnd *sc = ctask->sc;
Alex Aizman7ba24712005-08-04 19:30:08 -0700530 int datasn = be32_to_cpu(rhdr->datasn);
Boaz Harrosh94795b62008-04-18 10:11:53 -0500531 unsigned total_in_length = scsi_in(sc)->length;
Alex Aizman7ba24712005-08-04 19:30:08 -0700532
Mike Christie77a23c22007-05-30 12:57:18 -0500533 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
Mike Christie5bb0b552006-04-06 21:26:46 -0500534 if (tcp_conn->in.datalen == 0)
Alex Aizman7ba24712005-08-04 19:30:08 -0700535 return 0;
536
Mike Christied473cc72007-05-30 12:57:14 -0500537 if (tcp_ctask->exp_datasn != datasn) {
538 debug_tcp("%s: ctask->exp_datasn(%d) != rhdr->datasn(%d)\n",
539 __FUNCTION__, tcp_ctask->exp_datasn, datasn);
Alex Aizman7ba24712005-08-04 19:30:08 -0700540 return ISCSI_ERR_DATASN;
Mike Christied473cc72007-05-30 12:57:14 -0500541 }
Alex Aizman7ba24712005-08-04 19:30:08 -0700542
Mike Christied473cc72007-05-30 12:57:14 -0500543 tcp_ctask->exp_datasn++;
Alex Aizman7ba24712005-08-04 19:30:08 -0700544
Mike Christie5bb0b552006-04-06 21:26:46 -0500545 tcp_ctask->data_offset = be32_to_cpu(rhdr->offset);
Boaz Harrosh94795b62008-04-18 10:11:53 -0500546 if (tcp_ctask->data_offset + tcp_conn->in.datalen > total_in_length) {
Mike Christie857ae0b2007-05-30 12:57:15 -0500547 debug_tcp("%s: data_offset(%d) + data_len(%d) > total_length_in(%d)\n",
548 __FUNCTION__, tcp_ctask->data_offset,
Boaz Harrosh94795b62008-04-18 10:11:53 -0500549 tcp_conn->in.datalen, total_in_length);
Alex Aizman7ba24712005-08-04 19:30:08 -0700550 return ISCSI_ERR_DATA_OFFSET;
Mike Christie857ae0b2007-05-30 12:57:15 -0500551 }
Alex Aizman7ba24712005-08-04 19:30:08 -0700552
553 if (rhdr->flags & ISCSI_FLAG_DATA_STATUS) {
Boaz Harrosh7207fea2007-12-13 12:43:22 -0600554 sc->result = (DID_OK << 16) | rhdr->cmd_status;
Alex Aizman7ba24712005-08-04 19:30:08 -0700555 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
Boaz Harrosh7207fea2007-12-13 12:43:22 -0600556 if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
557 ISCSI_FLAG_DATA_OVERFLOW)) {
Alex Aizman7ba24712005-08-04 19:30:08 -0700558 int res_count = be32_to_cpu(rhdr->residual_count);
559
560 if (res_count > 0 &&
Boaz Harrosh7207fea2007-12-13 12:43:22 -0600561 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
Boaz Harrosh94795b62008-04-18 10:11:53 -0500562 res_count <= total_in_length))
563 scsi_in(sc)->resid = res_count;
Boaz Harrosh7207fea2007-12-13 12:43:22 -0600564 else
Alex Aizman7ba24712005-08-04 19:30:08 -0700565 sc->result = (DID_BAD_TARGET << 16) |
566 rhdr->cmd_status;
Boaz Harrosh7207fea2007-12-13 12:43:22 -0600567 }
Alex Aizman7ba24712005-08-04 19:30:08 -0700568 }
569
570 conn->datain_pdus_cnt++;
571 return 0;
572}
573
574/**
575 * iscsi_solicit_data_init - initialize first Data-Out
576 * @conn: iscsi connection
577 * @ctask: scsi command task
578 * @r2t: R2T info
579 *
580 * Notes:
581 * Initialize first Data-Out within this R2T sequence and finds
582 * proper data_offset within this SCSI command.
583 *
584 * This function is called with connection lock taken.
585 **/
586static void
587iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
588 struct iscsi_r2t_info *r2t)
589{
590 struct iscsi_data *hdr;
Alex Aizman7ba24712005-08-04 19:30:08 -0700591
Mike Christieffbfe922006-05-18 20:31:36 -0500592 hdr = &r2t->dtask.hdr;
Alex Aizman7ba24712005-08-04 19:30:08 -0700593 memset(hdr, 0, sizeof(struct iscsi_data));
594 hdr->ttt = r2t->ttt;
595 hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
596 r2t->solicit_datasn++;
597 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
Mike Christie5bb0b552006-04-06 21:26:46 -0500598 memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
599 hdr->itt = ctask->hdr->itt;
Alex Aizman7ba24712005-08-04 19:30:08 -0700600 hdr->exp_statsn = r2t->exp_statsn;
601 hdr->offset = cpu_to_be32(r2t->data_offset);
602 if (r2t->data_length > conn->max_xmit_dlength) {
603 hton24(hdr->dlength, conn->max_xmit_dlength);
604 r2t->data_count = conn->max_xmit_dlength;
605 hdr->flags = 0;
606 } else {
607 hton24(hdr->dlength, r2t->data_length);
608 r2t->data_count = r2t->data_length;
609 hdr->flags = ISCSI_FLAG_CMD_FINAL;
610 }
611 conn->dataout_pdus_cnt++;
612
613 r2t->sent = 0;
Alex Aizman7ba24712005-08-04 19:30:08 -0700614}
615
616/**
617 * iscsi_r2t_rsp - iSCSI R2T Response processing
618 * @conn: iscsi connection
619 * @ctask: scsi command task
620 **/
621static int
622iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
623{
624 struct iscsi_r2t_info *r2t;
625 struct iscsi_session *session = conn->session;
Mike Christie5bb0b552006-04-06 21:26:46 -0500626 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
627 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
628 struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr;
Alex Aizman7ba24712005-08-04 19:30:08 -0700629 int r2tsn = be32_to_cpu(rhdr->r2tsn);
630 int rc;
631
Mike Christie98a94162006-08-31 18:09:26 -0400632 if (tcp_conn->in.datalen) {
Mike Christie322d7392008-01-31 13:36:52 -0600633 iscsi_conn_printk(KERN_ERR, conn,
634 "invalid R2t with datalen %d\n",
635 tcp_conn->in.datalen);
Alex Aizman7ba24712005-08-04 19:30:08 -0700636 return ISCSI_ERR_DATALEN;
Mike Christie98a94162006-08-31 18:09:26 -0400637 }
Alex Aizman7ba24712005-08-04 19:30:08 -0700638
Mike Christied473cc72007-05-30 12:57:14 -0500639 if (tcp_ctask->exp_datasn != r2tsn){
640 debug_tcp("%s: ctask->exp_datasn(%d) != rhdr->r2tsn(%d)\n",
641 __FUNCTION__, tcp_ctask->exp_datasn, r2tsn);
Alex Aizman7ba24712005-08-04 19:30:08 -0700642 return ISCSI_ERR_R2TSN;
Mike Christied473cc72007-05-30 12:57:14 -0500643 }
Alex Aizman7ba24712005-08-04 19:30:08 -0700644
Alex Aizman7ba24712005-08-04 19:30:08 -0700645 /* fill-in new R2T associated with the task */
Mike Christie77a23c22007-05-30 12:57:18 -0500646 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
647
Mike Christie843c0a82007-12-13 12:43:20 -0600648 if (!ctask->sc || session->state != ISCSI_STATE_LOGGED_IN) {
Mike Christie322d7392008-01-31 13:36:52 -0600649 iscsi_conn_printk(KERN_INFO, conn,
650 "dropping R2T itt %d in recovery.\n",
651 ctask->itt);
Alex Aizman7ba24712005-08-04 19:30:08 -0700652 return 0;
653 }
Mike Christieb6c395e2006-07-24 15:47:15 -0500654
Mike Christie5bb0b552006-04-06 21:26:46 -0500655 rc = __kfifo_get(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
Alex Aizman7ba24712005-08-04 19:30:08 -0700656 BUG_ON(!rc);
657
658 r2t->exp_statsn = rhdr->statsn;
659 r2t->data_length = be32_to_cpu(rhdr->data_length);
Mike Christie98a94162006-08-31 18:09:26 -0400660 if (r2t->data_length == 0) {
Mike Christie322d7392008-01-31 13:36:52 -0600661 iscsi_conn_printk(KERN_ERR, conn,
662 "invalid R2T with zero data len\n");
Olaf Kirch03766a12007-12-13 12:43:36 -0600663 __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
664 sizeof(void*));
Alex Aizman7ba24712005-08-04 19:30:08 -0700665 return ISCSI_ERR_DATALEN;
666 }
667
Mike Christie98a94162006-08-31 18:09:26 -0400668 if (r2t->data_length > session->max_burst)
669 debug_scsi("invalid R2T with data len %u and max burst %u."
670 "Attempting to execute request.\n",
671 r2t->data_length, session->max_burst);
672
Alex Aizman7ba24712005-08-04 19:30:08 -0700673 r2t->data_offset = be32_to_cpu(rhdr->data_offset);
Boaz Harrosh94795b62008-04-18 10:11:53 -0500674 if (r2t->data_offset + r2t->data_length > scsi_out(ctask->sc)->length) {
Mike Christie322d7392008-01-31 13:36:52 -0600675 iscsi_conn_printk(KERN_ERR, conn,
676 "invalid R2T with data len %u at offset %u "
677 "and total length %d\n", r2t->data_length,
Boaz Harrosh94795b62008-04-18 10:11:53 -0500678 r2t->data_offset, scsi_out(ctask->sc)->length);
Olaf Kirch03766a12007-12-13 12:43:36 -0600679 __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
680 sizeof(void*));
Alex Aizman7ba24712005-08-04 19:30:08 -0700681 return ISCSI_ERR_DATALEN;
682 }
683
684 r2t->ttt = rhdr->ttt; /* no flip */
685 r2t->solicit_datasn = 0;
686
687 iscsi_solicit_data_init(conn, ctask, r2t);
688
Mike Christied473cc72007-05-30 12:57:14 -0500689 tcp_ctask->exp_datasn = r2tsn + 1;
Mike Christie5bb0b552006-04-06 21:26:46 -0500690 __kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
Alex Aizman7ba24712005-08-04 19:30:08 -0700691 conn->r2t_pdus_cnt++;
Mike Christie843c0a82007-12-13 12:43:20 -0600692
693 iscsi_requeue_ctask(ctask);
Alex Aizman7ba24712005-08-04 19:30:08 -0700694 return 0;
695}
696
Olaf Kirchda32dd62007-12-13 12:43:21 -0600697/*
698 * Handle incoming reply to DataIn command
699 */
Alex Aizman7ba24712005-08-04 19:30:08 -0700700static int
Olaf Kirchda32dd62007-12-13 12:43:21 -0600701iscsi_tcp_process_data_in(struct iscsi_tcp_conn *tcp_conn,
Olaf Kircha8ac6312007-12-13 12:43:35 -0600702 struct iscsi_segment *segment)
Olaf Kirchda32dd62007-12-13 12:43:21 -0600703{
704 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
705 struct iscsi_hdr *hdr = tcp_conn->in.hdr;
706 int rc;
707
Olaf Kircha8ac6312007-12-13 12:43:35 -0600708 if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
Olaf Kirchda32dd62007-12-13 12:43:21 -0600709 return ISCSI_ERR_DATA_DGST;
710
711 /* check for non-exceptional status */
712 if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
713 rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
714 if (rc)
715 return rc;
716 }
717
718 iscsi_tcp_hdr_recv_prep(tcp_conn);
719 return 0;
720}
721
722/**
723 * iscsi_tcp_hdr_dissect - process PDU header
724 * @conn: iSCSI connection
725 * @hdr: PDU header
726 *
727 * This function analyzes the header of the PDU received,
728 * and performs several sanity checks. If the PDU is accompanied
729 * by data, the receive buffer is set up to copy the incoming data
730 * to the correct location.
731 */
732static int
733iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
Alex Aizman7ba24712005-08-04 19:30:08 -0700734{
Mike Christie5bb0b552006-04-06 21:26:46 -0500735 int rc = 0, opcode, ahslen;
Alex Aizman7ba24712005-08-04 19:30:08 -0700736 struct iscsi_session *session = conn->session;
Mike Christie5bb0b552006-04-06 21:26:46 -0500737 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600738 struct iscsi_cmd_task *ctask;
739 uint32_t itt;
Alex Aizman7ba24712005-08-04 19:30:08 -0700740
741 /* verify PDU length */
Mike Christie5bb0b552006-04-06 21:26:46 -0500742 tcp_conn->in.datalen = ntoh24(hdr->dlength);
743 if (tcp_conn->in.datalen > conn->max_recv_dlength) {
Mike Christie322d7392008-01-31 13:36:52 -0600744 iscsi_conn_printk(KERN_ERR, conn,
745 "iscsi_tcp: datalen %d > %d\n",
746 tcp_conn->in.datalen, conn->max_recv_dlength);
Alex Aizman7ba24712005-08-04 19:30:08 -0700747 return ISCSI_ERR_DATALEN;
748 }
Alex Aizman7ba24712005-08-04 19:30:08 -0700749
Olaf Kirchda32dd62007-12-13 12:43:21 -0600750 /* Additional header segments. So far, we don't
751 * process additional headers.
752 */
Mike Christie5bb0b552006-04-06 21:26:46 -0500753 ahslen = hdr->hlength << 2;
Alex Aizman7ba24712005-08-04 19:30:08 -0700754
Mike Christie5bb0b552006-04-06 21:26:46 -0500755 opcode = hdr->opcode & ISCSI_OPCODE_MASK;
Alex Aizman7ba24712005-08-04 19:30:08 -0700756 /* verify itt (itt encoding: age+cid+itt) */
Mike Christie5bb0b552006-04-06 21:26:46 -0500757 rc = iscsi_verify_itt(conn, hdr, &itt);
Mike Christie7a53dc52007-12-13 12:43:37 -0600758 if (rc)
Mike Christie5bb0b552006-04-06 21:26:46 -0500759 return rc;
Alex Aizman7ba24712005-08-04 19:30:08 -0700760
Olaf Kirchda32dd62007-12-13 12:43:21 -0600761 debug_tcp("opcode 0x%x ahslen %d datalen %d\n",
762 opcode, ahslen, tcp_conn->in.datalen);
Alex Aizman7ba24712005-08-04 19:30:08 -0700763
Mike Christie5bb0b552006-04-06 21:26:46 -0500764 switch(opcode) {
765 case ISCSI_OP_SCSI_DATA_IN:
Olaf Kirchda32dd62007-12-13 12:43:21 -0600766 ctask = session->cmds[itt];
Mike Christie4545a882007-12-13 12:43:40 -0600767 spin_lock(&conn->session->lock);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600768 rc = iscsi_data_rsp(conn, ctask);
Mike Christie4545a882007-12-13 12:43:40 -0600769 spin_unlock(&conn->session->lock);
Mike Christie275fd7d2006-07-24 15:47:17 -0500770 if (rc)
771 return rc;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600772 if (tcp_conn->in.datalen) {
773 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
774 struct hash_desc *rx_hash = NULL;
Boaz Harrosh94795b62008-04-18 10:11:53 -0500775 struct scsi_data_buffer *sdb = scsi_in(ctask->sc);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600776
777 /*
778 * Setup copy of Data-In into the Scsi_Cmnd
779 * Scatterlist case:
Olaf Kircha8ac6312007-12-13 12:43:35 -0600780 * We set up the iscsi_segment to point to the next
Olaf Kirchda32dd62007-12-13 12:43:21 -0600781 * scatterlist entry to copy to. As we go along,
782 * we move on to the next scatterlist entry and
783 * update the digest per-entry.
784 */
785 if (conn->datadgst_en)
786 rx_hash = &tcp_conn->rx_hash;
787
788 debug_tcp("iscsi_tcp_begin_data_in(%p, offset=%d, "
789 "datalen=%d)\n", tcp_conn,
790 tcp_ctask->data_offset,
791 tcp_conn->in.datalen);
Olaf Kircha8ac6312007-12-13 12:43:35 -0600792 return iscsi_segment_seek_sg(&tcp_conn->in.segment,
Boaz Harrosh94795b62008-04-18 10:11:53 -0500793 sdb->table.sgl,
794 sdb->table.nents,
Olaf Kircha8ac6312007-12-13 12:43:35 -0600795 tcp_ctask->data_offset,
796 tcp_conn->in.datalen,
797 iscsi_tcp_process_data_in,
798 rx_hash);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600799 }
Mike Christie5bb0b552006-04-06 21:26:46 -0500800 /* fall through */
801 case ISCSI_OP_SCSI_CMD_RSP:
Olaf Kirchda32dd62007-12-13 12:43:21 -0600802 if (tcp_conn->in.datalen) {
803 iscsi_tcp_data_recv_prep(tcp_conn);
804 return 0;
805 }
806 rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
Mike Christie5bb0b552006-04-06 21:26:46 -0500807 break;
808 case ISCSI_OP_R2T:
Olaf Kirchda32dd62007-12-13 12:43:21 -0600809 ctask = session->cmds[itt];
Mike Christie5bb0b552006-04-06 21:26:46 -0500810 if (ahslen)
811 rc = ISCSI_ERR_AHSLEN;
Mike Christie4545a882007-12-13 12:43:40 -0600812 else if (ctask->sc->sc_data_direction == DMA_TO_DEVICE) {
813 spin_lock(&session->lock);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600814 rc = iscsi_r2t_rsp(conn, ctask);
Mike Christie4545a882007-12-13 12:43:40 -0600815 spin_unlock(&session->lock);
816 } else
Mike Christie5bb0b552006-04-06 21:26:46 -0500817 rc = ISCSI_ERR_PROTO;
818 break;
819 case ISCSI_OP_LOGIN_RSP:
820 case ISCSI_OP_TEXT_RSP:
Mike Christie5bb0b552006-04-06 21:26:46 -0500821 case ISCSI_OP_REJECT:
822 case ISCSI_OP_ASYNC_EVENT:
Mike Christiec8dc1e52006-07-24 15:47:39 -0500823 /*
824 * It is possible that we could get a PDU with a buffer larger
825 * than 8K, but there are no targets that currently do this.
826 * For now we fail until we find a vendor that needs it
827 */
Olaf Kirchda32dd62007-12-13 12:43:21 -0600828 if (ISCSI_DEF_MAX_RECV_SEG_LEN < tcp_conn->in.datalen) {
Mike Christie322d7392008-01-31 13:36:52 -0600829 iscsi_conn_printk(KERN_ERR, conn,
830 "iscsi_tcp: received buffer of "
831 "len %u but conn buffer is only %u "
832 "(opcode %0x)\n",
833 tcp_conn->in.datalen,
834 ISCSI_DEF_MAX_RECV_SEG_LEN, opcode);
Mike Christiec8dc1e52006-07-24 15:47:39 -0500835 rc = ISCSI_ERR_PROTO;
836 break;
837 }
838
Olaf Kirchda32dd62007-12-13 12:43:21 -0600839 /* If there's data coming in with the response,
840 * receive it to the connection's buffer.
841 */
842 if (tcp_conn->in.datalen) {
843 iscsi_tcp_data_recv_prep(tcp_conn);
844 return 0;
845 }
Mike Christie5bb0b552006-04-06 21:26:46 -0500846 /* fall through */
Mike Christiec8dc1e52006-07-24 15:47:39 -0500847 case ISCSI_OP_LOGOUT_RSP:
848 case ISCSI_OP_NOOP_IN:
Mike Christie5bb0b552006-04-06 21:26:46 -0500849 case ISCSI_OP_SCSI_TMFUNC_RSP:
850 rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
851 break;
852 default:
853 rc = ISCSI_ERR_BAD_OPCODE;
854 break;
855 }
Alex Aizman7ba24712005-08-04 19:30:08 -0700856
Olaf Kirchda32dd62007-12-13 12:43:21 -0600857 if (rc == 0) {
858 /* Anything that comes with data should have
859 * been handled above. */
860 if (tcp_conn->in.datalen)
861 return ISCSI_ERR_PROTO;
862 iscsi_tcp_hdr_recv_prep(tcp_conn);
863 }
864
Alex Aizman7ba24712005-08-04 19:30:08 -0700865 return rc;
Alex Aizman7ba24712005-08-04 19:30:08 -0700866}
867
Olaf Kirchda32dd62007-12-13 12:43:21 -0600868/**
869 * iscsi_tcp_hdr_recv_done - process PDU header
870 *
871 * This is the callback invoked when the PDU header has
872 * been received. If the header is followed by additional
873 * header segments, we go back for more data.
874 */
Alex Aizman7ba24712005-08-04 19:30:08 -0700875static int
Olaf Kirchda32dd62007-12-13 12:43:21 -0600876iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
Olaf Kircha8ac6312007-12-13 12:43:35 -0600877 struct iscsi_segment *segment)
Alex Aizman7ba24712005-08-04 19:30:08 -0700878{
Olaf Kirchda32dd62007-12-13 12:43:21 -0600879 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
880 struct iscsi_hdr *hdr;
Alex Aizman7ba24712005-08-04 19:30:08 -0700881
Olaf Kirchda32dd62007-12-13 12:43:21 -0600882 /* Check if there are additional header segments
883 * *prior* to computing the digest, because we
884 * may need to go back to the caller for more.
885 */
886 hdr = (struct iscsi_hdr *) tcp_conn->in.hdr_buf;
Olaf Kircha8ac6312007-12-13 12:43:35 -0600887 if (segment->copied == sizeof(struct iscsi_hdr) && hdr->hlength) {
Olaf Kirchda32dd62007-12-13 12:43:21 -0600888 /* Bump the header length - the caller will
889 * just loop around and get the AHS for us, and
890 * call again. */
891 unsigned int ahslen = hdr->hlength << 2;
Alex Aizman7ba24712005-08-04 19:30:08 -0700892
Olaf Kirchda32dd62007-12-13 12:43:21 -0600893 /* Make sure we don't overflow */
894 if (sizeof(*hdr) + ahslen > sizeof(tcp_conn->in.hdr_buf))
895 return ISCSI_ERR_AHSLEN;
896
Olaf Kircha8ac6312007-12-13 12:43:35 -0600897 segment->total_size += ahslen;
898 segment->size += ahslen;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600899 return 0;
Alex Aizman7ba24712005-08-04 19:30:08 -0700900 }
Olaf Kirchda32dd62007-12-13 12:43:21 -0600901
902 /* We're done processing the header. See if we're doing
903 * header digests; if so, set up the recv_digest buffer
904 * and go back for more. */
905 if (conn->hdrdgst_en) {
Olaf Kircha8ac6312007-12-13 12:43:35 -0600906 if (segment->digest_len == 0) {
907 iscsi_tcp_segment_splice_digest(segment,
908 segment->recv_digest);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600909 return 0;
910 }
911 iscsi_tcp_dgst_header(&tcp_conn->rx_hash, hdr,
Olaf Kircha8ac6312007-12-13 12:43:35 -0600912 segment->total_copied - ISCSI_DIGEST_SIZE,
913 segment->digest);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600914
Olaf Kircha8ac6312007-12-13 12:43:35 -0600915 if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
Olaf Kirchda32dd62007-12-13 12:43:21 -0600916 return ISCSI_ERR_HDR_DGST;
917 }
918
919 tcp_conn->in.hdr = hdr;
920 return iscsi_tcp_hdr_dissect(conn, hdr);
Alex Aizman7ba24712005-08-04 19:30:08 -0700921}
922
923/**
Olaf Kirchda32dd62007-12-13 12:43:21 -0600924 * iscsi_tcp_recv - TCP receive in sendfile fashion
Alex Aizman7ba24712005-08-04 19:30:08 -0700925 * @rd_desc: read descriptor
926 * @skb: socket buffer
927 * @offset: offset in skb
928 * @len: skb->len - offset
929 **/
930static int
Olaf Kirchda32dd62007-12-13 12:43:21 -0600931iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
932 unsigned int offset, size_t len)
Alex Aizman7ba24712005-08-04 19:30:08 -0700933{
Alex Aizman7ba24712005-08-04 19:30:08 -0700934 struct iscsi_conn *conn = rd_desc->arg.data;
Mike Christie5bb0b552006-04-06 21:26:46 -0500935 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
Olaf Kircha8ac6312007-12-13 12:43:35 -0600936 struct iscsi_segment *segment = &tcp_conn->in.segment;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600937 struct skb_seq_state seq;
938 unsigned int consumed = 0;
939 int rc = 0;
Alex Aizman7ba24712005-08-04 19:30:08 -0700940
Olaf Kirchda32dd62007-12-13 12:43:21 -0600941 debug_tcp("in %d bytes\n", skb->len - offset);
Alex Aizman7ba24712005-08-04 19:30:08 -0700942
943 if (unlikely(conn->suspend_rx)) {
944 debug_tcp("conn %d Rx suspended!\n", conn->id);
945 return 0;
946 }
947
Olaf Kirchda32dd62007-12-13 12:43:21 -0600948 skb_prepare_seq_read(skb, offset, skb->len, &seq);
949 while (1) {
950 unsigned int avail;
951 const u8 *ptr;
Alex Aizman7ba24712005-08-04 19:30:08 -0700952
Olaf Kirchda32dd62007-12-13 12:43:21 -0600953 avail = skb_seq_read(consumed, &ptr, &seq);
Olaf Kircha8ac6312007-12-13 12:43:35 -0600954 if (avail == 0) {
955 debug_tcp("no more data avail. Consumed %d\n",
956 consumed);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600957 break;
Olaf Kircha8ac6312007-12-13 12:43:35 -0600958 }
959 BUG_ON(segment->copied >= segment->size);
Alex Aizman7ba24712005-08-04 19:30:08 -0700960
Olaf Kirchda32dd62007-12-13 12:43:21 -0600961 debug_tcp("skb %p ptr=%p avail=%u\n", skb, ptr, avail);
Olaf Kircha8ac6312007-12-13 12:43:35 -0600962 rc = iscsi_tcp_segment_recv(tcp_conn, segment, ptr, avail);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600963 BUG_ON(rc == 0);
964 consumed += rc;
Mike Christie5bb0b552006-04-06 21:26:46 -0500965
Olaf Kircha8ac6312007-12-13 12:43:35 -0600966 if (segment->total_copied >= segment->total_size) {
967 debug_tcp("segment done\n");
968 rc = segment->done(tcp_conn, segment);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600969 if (rc != 0) {
970 skb_abort_seq_read(&seq);
971 goto error;
Mike Christiedbdb0162007-05-30 12:57:20 -0500972 }
Mike Christiedbdb0162007-05-30 12:57:20 -0500973
Olaf Kirchda32dd62007-12-13 12:43:21 -0600974 /* The done() functions sets up the
Olaf Kircha8ac6312007-12-13 12:43:35 -0600975 * next segment. */
Alex Aizman7ba24712005-08-04 19:30:08 -0700976 }
977 }
Olaf Kircha8ac6312007-12-13 12:43:35 -0600978 skb_abort_seq_read(&seq);
Olaf Kirchda32dd62007-12-13 12:43:21 -0600979 conn->rxdata_octets += consumed;
980 return consumed;
Alex Aizman7ba24712005-08-04 19:30:08 -0700981
Olaf Kirchda32dd62007-12-13 12:43:21 -0600982error:
983 debug_tcp("Error receiving PDU, errno=%d\n", rc);
984 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
985 return 0;
Alex Aizman7ba24712005-08-04 19:30:08 -0700986}
987
988static void
989iscsi_tcp_data_ready(struct sock *sk, int flag)
990{
991 struct iscsi_conn *conn = sk->sk_user_data;
Olaf Kirchda32dd62007-12-13 12:43:21 -0600992 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
Alex Aizman7ba24712005-08-04 19:30:08 -0700993 read_descriptor_t rd_desc;
994
995 read_lock(&sk->sk_callback_lock);
996
Mike Christie665b44a2006-05-02 19:46:49 -0500997 /*
Olaf Kirchda32dd62007-12-13 12:43:21 -0600998 * Use rd_desc to pass 'conn' to iscsi_tcp_recv.
Mike Christie665b44a2006-05-02 19:46:49 -0500999 * We set count to 1 because we want the network layer to
Olaf Kirchda32dd62007-12-13 12:43:21 -06001000 * hand us all the skbs that are available. iscsi_tcp_recv
Mike Christie665b44a2006-05-02 19:46:49 -05001001 * handled pdus that cross buffers or pdus that still need data.
1002 */
Alex Aizman7ba24712005-08-04 19:30:08 -07001003 rd_desc.arg.data = conn;
Mike Christie665b44a2006-05-02 19:46:49 -05001004 rd_desc.count = 1;
Olaf Kirchda32dd62007-12-13 12:43:21 -06001005 tcp_read_sock(sk, &rd_desc, iscsi_tcp_recv);
Alex Aizman7ba24712005-08-04 19:30:08 -07001006
1007 read_unlock(&sk->sk_callback_lock);
Olaf Kirchda32dd62007-12-13 12:43:21 -06001008
1009 /* If we had to (atomically) map a highmem page,
1010 * unmap it now. */
Olaf Kircha8ac6312007-12-13 12:43:35 -06001011 iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
Alex Aizman7ba24712005-08-04 19:30:08 -07001012}
1013
1014static void
1015iscsi_tcp_state_change(struct sock *sk)
1016{
Mike Christie5bb0b552006-04-06 21:26:46 -05001017 struct iscsi_tcp_conn *tcp_conn;
Alex Aizman7ba24712005-08-04 19:30:08 -07001018 struct iscsi_conn *conn;
1019 struct iscsi_session *session;
1020 void (*old_state_change)(struct sock *);
1021
1022 read_lock(&sk->sk_callback_lock);
1023
1024 conn = (struct iscsi_conn*)sk->sk_user_data;
1025 session = conn->session;
1026
Mike Christiee6273992005-11-29 23:12:49 -06001027 if ((sk->sk_state == TCP_CLOSE_WAIT ||
1028 sk->sk_state == TCP_CLOSE) &&
1029 !atomic_read(&sk->sk_rmem_alloc)) {
Alex Aizman7ba24712005-08-04 19:30:08 -07001030 debug_tcp("iscsi_tcp_state_change: TCP_CLOSE|TCP_CLOSE_WAIT\n");
1031 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1032 }
1033
Mike Christie5bb0b552006-04-06 21:26:46 -05001034 tcp_conn = conn->dd_data;
1035 old_state_change = tcp_conn->old_state_change;
Alex Aizman7ba24712005-08-04 19:30:08 -07001036
1037 read_unlock(&sk->sk_callback_lock);
1038
1039 old_state_change(sk);
1040}
1041
1042/**
1043 * iscsi_write_space - Called when more output buffer space is available
1044 * @sk: socket space is available for
1045 **/
1046static void
1047iscsi_write_space(struct sock *sk)
1048{
1049 struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
Mike Christie5bb0b552006-04-06 21:26:46 -05001050 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1051
1052 tcp_conn->old_write_space(sk);
Alex Aizman7ba24712005-08-04 19:30:08 -07001053 debug_tcp("iscsi_write_space: cid %d\n", conn->id);
Mike Christie55e32992006-01-13 18:05:53 -06001054 scsi_queue_work(conn->session->host, &conn->xmitwork);
Alex Aizman7ba24712005-08-04 19:30:08 -07001055}
1056
1057static void
1058iscsi_conn_set_callbacks(struct iscsi_conn *conn)
1059{
Mike Christie5bb0b552006-04-06 21:26:46 -05001060 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1061 struct sock *sk = tcp_conn->sock->sk;
Alex Aizman7ba24712005-08-04 19:30:08 -07001062
1063 /* assign new callbacks */
1064 write_lock_bh(&sk->sk_callback_lock);
1065 sk->sk_user_data = conn;
Mike Christie5bb0b552006-04-06 21:26:46 -05001066 tcp_conn->old_data_ready = sk->sk_data_ready;
1067 tcp_conn->old_state_change = sk->sk_state_change;
1068 tcp_conn->old_write_space = sk->sk_write_space;
Alex Aizman7ba24712005-08-04 19:30:08 -07001069 sk->sk_data_ready = iscsi_tcp_data_ready;
1070 sk->sk_state_change = iscsi_tcp_state_change;
1071 sk->sk_write_space = iscsi_write_space;
1072 write_unlock_bh(&sk->sk_callback_lock);
1073}
1074
1075static void
Mike Christie1c834692006-07-24 15:47:26 -05001076iscsi_conn_restore_callbacks(struct iscsi_tcp_conn *tcp_conn)
Alex Aizman7ba24712005-08-04 19:30:08 -07001077{
Mike Christie5bb0b552006-04-06 21:26:46 -05001078 struct sock *sk = tcp_conn->sock->sk;
Alex Aizman7ba24712005-08-04 19:30:08 -07001079
1080 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
1081 write_lock_bh(&sk->sk_callback_lock);
1082 sk->sk_user_data = NULL;
Mike Christie5bb0b552006-04-06 21:26:46 -05001083 sk->sk_data_ready = tcp_conn->old_data_ready;
1084 sk->sk_state_change = tcp_conn->old_state_change;
1085 sk->sk_write_space = tcp_conn->old_write_space;
Alex Aizman7ba24712005-08-04 19:30:08 -07001086 sk->sk_no_check = 0;
1087 write_unlock_bh(&sk->sk_callback_lock);
1088}
1089
1090/**
Olaf Kircha8ac6312007-12-13 12:43:35 -06001091 * iscsi_xmit - TCP transmit
1092 **/
1093static int
1094iscsi_xmit(struct iscsi_conn *conn)
Alex Aizman7ba24712005-08-04 19:30:08 -07001095{
Mike Christie5bb0b552006-04-06 21:26:46 -05001096 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
Olaf Kircha8ac6312007-12-13 12:43:35 -06001097 struct iscsi_segment *segment = &tcp_conn->out.segment;
1098 unsigned int consumed = 0;
1099 int rc = 0;
Alex Aizman7ba24712005-08-04 19:30:08 -07001100
Olaf Kircha8ac6312007-12-13 12:43:35 -06001101 while (1) {
1102 rc = iscsi_tcp_xmit_segment(tcp_conn, segment);
1103 if (rc < 0)
1104 goto error;
1105 if (rc == 0)
1106 break;
1107
1108 consumed += rc;
1109
1110 if (segment->total_copied >= segment->total_size) {
1111 if (segment->done != NULL) {
1112 rc = segment->done(tcp_conn, segment);
1113 if (rc < 0)
1114 goto error;
1115 }
1116 }
1117 }
1118
1119 debug_tcp("xmit %d bytes\n", consumed);
1120
1121 conn->txdata_octets += consumed;
1122 return consumed;
1123
1124error:
1125 /* Transmit error. We could initiate error recovery
1126 * here. */
1127 debug_tcp("Error sending PDU, errno=%d\n", rc);
1128 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1129 return rc;
1130}
1131
1132/**
1133 * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit
1134 */
1135static inline int
1136iscsi_tcp_xmit_qlen(struct iscsi_conn *conn)
1137{
1138 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1139 struct iscsi_segment *segment = &tcp_conn->out.segment;
1140
1141 return segment->total_copied - segment->total_size;
1142}
1143
1144static inline int
1145iscsi_tcp_flush(struct iscsi_conn *conn)
1146{
1147 int rc;
1148
1149 while (iscsi_tcp_xmit_qlen(conn)) {
1150 rc = iscsi_xmit(conn);
1151 if (rc == 0)
1152 return -EAGAIN;
1153 if (rc < 0)
1154 return rc;
1155 }
1156
1157 return 0;
1158}
1159
1160/*
1161 * This is called when we're done sending the header.
1162 * Simply copy the data_segment to the send segment, and return.
1163 */
1164static int
1165iscsi_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
1166 struct iscsi_segment *segment)
1167{
1168 tcp_conn->out.segment = tcp_conn->out.data_segment;
1169 debug_tcp("Header done. Next segment size %u total_size %u\n",
1170 tcp_conn->out.segment.size, tcp_conn->out.segment.total_size);
1171 return 0;
1172}
1173
1174static void
1175iscsi_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, size_t hdrlen)
1176{
1177 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1178
1179 debug_tcp("%s(%p%s)\n", __FUNCTION__, tcp_conn,
1180 conn->hdrdgst_en? ", digest enabled" : "");
1181
1182 /* Clear the data segment - needs to be filled in by the
1183 * caller using iscsi_tcp_send_data_prep() */
1184 memset(&tcp_conn->out.data_segment, 0, sizeof(struct iscsi_segment));
1185
1186 /* If header digest is enabled, compute the CRC and
1187 * place the digest into the same buffer. We make
1188 * sure that both iscsi_tcp_ctask and mtask have
1189 * sufficient room.
Mike Christie7cae5152006-01-13 18:05:47 -06001190 */
Olaf Kircha8ac6312007-12-13 12:43:35 -06001191 if (conn->hdrdgst_en) {
1192 iscsi_tcp_dgst_header(&tcp_conn->tx_hash, hdr, hdrlen,
1193 hdr + hdrlen);
1194 hdrlen += ISCSI_DIGEST_SIZE;
Mike Christie3219e522006-05-30 00:37:28 -05001195 }
1196
Olaf Kircha8ac6312007-12-13 12:43:35 -06001197 /* Remember header pointer for later, when we need
1198 * to decide whether there's a payload to go along
1199 * with the header. */
1200 tcp_conn->out.hdr = hdr;
1201
1202 iscsi_segment_init_linear(&tcp_conn->out.segment, hdr, hdrlen,
1203 iscsi_tcp_send_hdr_done, NULL);
Alex Aizman7ba24712005-08-04 19:30:08 -07001204}
1205
Olaf Kircha8ac6312007-12-13 12:43:35 -06001206/*
1207 * Prepare the send buffer for the payload data.
1208 * Padding and checksumming will all be taken care
1209 * of by the iscsi_segment routines.
1210 */
1211static int
1212iscsi_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
1213 unsigned int count, unsigned int offset,
1214 unsigned int len)
Alex Aizman7ba24712005-08-04 19:30:08 -07001215{
Olaf Kircha8ac6312007-12-13 12:43:35 -06001216 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1217 struct hash_desc *tx_hash = NULL;
1218 unsigned int hdr_spec_len;
Alex Aizman7ba24712005-08-04 19:30:08 -07001219
Olaf Kircha8ac6312007-12-13 12:43:35 -06001220 debug_tcp("%s(%p, offset=%d, datalen=%d%s)\n", __FUNCTION__,
1221 tcp_conn, offset, len,
1222 conn->datadgst_en? ", digest enabled" : "");
Alex Aizman7ba24712005-08-04 19:30:08 -07001223
Olaf Kircha8ac6312007-12-13 12:43:35 -06001224 /* Make sure the datalen matches what the caller
1225 said he would send. */
1226 hdr_spec_len = ntoh24(tcp_conn->out.hdr->dlength);
1227 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
Alex Aizman7ba24712005-08-04 19:30:08 -07001228
Olaf Kircha8ac6312007-12-13 12:43:35 -06001229 if (conn->datadgst_en)
1230 tx_hash = &tcp_conn->tx_hash;
1231
1232 return iscsi_segment_seek_sg(&tcp_conn->out.data_segment,
1233 sg, count, offset, len,
1234 NULL, tx_hash);
Alex Aizman7ba24712005-08-04 19:30:08 -07001235}
1236
Olaf Kircha8ac6312007-12-13 12:43:35 -06001237static void
1238iscsi_tcp_send_linear_data_prepare(struct iscsi_conn *conn, void *data,
1239 size_t len)
Alex Aizman7ba24712005-08-04 19:30:08 -07001240{
Olaf Kircha8ac6312007-12-13 12:43:35 -06001241 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1242 struct hash_desc *tx_hash = NULL;
1243 unsigned int hdr_spec_len;
Alex Aizman7ba24712005-08-04 19:30:08 -07001244
Olaf Kircha8ac6312007-12-13 12:43:35 -06001245 debug_tcp("%s(%p, datalen=%d%s)\n", __FUNCTION__, tcp_conn, len,
1246 conn->datadgst_en? ", digest enabled" : "");
Alex Aizman7ba24712005-08-04 19:30:08 -07001247
Olaf Kircha8ac6312007-12-13 12:43:35 -06001248 /* Make sure the datalen matches what the caller
1249 said he would send. */
1250 hdr_spec_len = ntoh24(tcp_conn->out.hdr->dlength);
1251 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
Alex Aizman7ba24712005-08-04 19:30:08 -07001252
Olaf Kircha8ac6312007-12-13 12:43:35 -06001253 if (conn->datadgst_en)
1254 tx_hash = &tcp_conn->tx_hash;
Alex Aizman7ba24712005-08-04 19:30:08 -07001255
Olaf Kircha8ac6312007-12-13 12:43:35 -06001256 iscsi_segment_init_linear(&tcp_conn->out.data_segment,
1257 data, len, NULL, tx_hash);
Alex Aizman7ba24712005-08-04 19:30:08 -07001258}
1259
Alex Aizman7ba24712005-08-04 19:30:08 -07001260/**
1261 * iscsi_solicit_data_cont - initialize next Data-Out
1262 * @conn: iscsi connection
1263 * @ctask: scsi command task
1264 * @r2t: R2T info
1265 * @left: bytes left to transfer
1266 *
1267 * Notes:
1268 * Initialize next Data-Out within this R2T sequence and continue
1269 * to process next Scatter-Gather element(if any) of this SCSI command.
1270 *
1271 * Called under connection lock.
1272 **/
Olaf Kircha8ac6312007-12-13 12:43:35 -06001273static int
Alex Aizman7ba24712005-08-04 19:30:08 -07001274iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
Olaf Kircha8ac6312007-12-13 12:43:35 -06001275 struct iscsi_r2t_info *r2t)
Alex Aizman7ba24712005-08-04 19:30:08 -07001276{
1277 struct iscsi_data *hdr;
Olaf Kircha8ac6312007-12-13 12:43:35 -06001278 int new_offset, left;
1279
1280 BUG_ON(r2t->data_length - r2t->sent < 0);
1281 left = r2t->data_length - r2t->sent;
1282 if (left == 0)
1283 return 0;
Alex Aizman7ba24712005-08-04 19:30:08 -07001284
Mike Christieffbfe922006-05-18 20:31:36 -05001285 hdr = &r2t->dtask.hdr;
Alex Aizman7ba24712005-08-04 19:30:08 -07001286 memset(hdr, 0, sizeof(struct iscsi_data));
1287 hdr->ttt = r2t->ttt;
1288 hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
1289 r2t->solicit_datasn++;
1290 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
Mike Christie5bb0b552006-04-06 21:26:46 -05001291 memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1292 hdr->itt = ctask->hdr->itt;
Alex Aizman7ba24712005-08-04 19:30:08 -07001293 hdr->exp_statsn = r2t->exp_statsn;
1294 new_offset = r2t->data_offset + r2t->sent;
1295 hdr->offset = cpu_to_be32(new_offset);
1296 if (left > conn->max_xmit_dlength) {
1297 hton24(hdr->dlength, conn->max_xmit_dlength);
1298 r2t->data_count = conn->max_xmit_dlength;
1299 } else {
1300 hton24(hdr->dlength, left);
1301 r2t->data_count = left;
1302 hdr->flags = ISCSI_FLAG_CMD_FINAL;
1303 }
Olaf Kircha8ac6312007-12-13 12:43:35 -06001304
Alex Aizman7ba24712005-08-04 19:30:08 -07001305 conn->dataout_pdus_cnt++;
Olaf Kircha8ac6312007-12-13 12:43:35 -06001306 return 1;
Alex Aizman7ba24712005-08-04 19:30:08 -07001307}
1308
1309/**
Olaf Kircha8ac6312007-12-13 12:43:35 -06001310 * iscsi_tcp_ctask - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
Alex Aizman7ba24712005-08-04 19:30:08 -07001311 * @conn: iscsi connection
1312 * @ctask: scsi command task
1313 * @sc: scsi command
1314 **/
Olaf Kircha8ac6312007-12-13 12:43:35 -06001315static int
1316iscsi_tcp_ctask_init(struct iscsi_cmd_task *ctask)
Alex Aizman7ba24712005-08-04 19:30:08 -07001317{
Mike Christie5bb0b552006-04-06 21:26:46 -05001318 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
Olaf Kircha8ac6312007-12-13 12:43:35 -06001319 struct iscsi_conn *conn = ctask->conn;
1320 struct scsi_cmnd *sc = ctask->sc;
1321 int err;
Alex Aizman7ba24712005-08-04 19:30:08 -07001322
Mike Christie5bb0b552006-04-06 21:26:46 -05001323 BUG_ON(__kfifo_len(tcp_ctask->r2tqueue));
Olaf Kircha8ac6312007-12-13 12:43:35 -06001324 tcp_ctask->sent = 0;
1325 tcp_ctask->exp_datasn = 0;
1326
1327 /* Prepare PDU, optionally w/ immediate data */
1328 debug_scsi("ctask deq [cid %d itt 0x%x imm %d unsol %d]\n",
1329 conn->id, ctask->itt, ctask->imm_count,
1330 ctask->unsol_count);
1331 iscsi_tcp_send_hdr_prep(conn, ctask->hdr, ctask->hdr_len);
1332
1333 if (!ctask->imm_count)
1334 return 0;
1335
1336 /* If we have immediate data, attach a payload */
Boaz Harrosh94795b62008-04-18 10:11:53 -05001337 err = iscsi_tcp_send_data_prep(conn, scsi_out(sc)->table.sgl,
1338 scsi_out(sc)->table.nents,
Olaf Kircha8ac6312007-12-13 12:43:35 -06001339 0, ctask->imm_count);
1340 if (err)
1341 return err;
1342 tcp_ctask->sent += ctask->imm_count;
1343 ctask->imm_count = 0;
1344 return 0;
Alex Aizman7ba24712005-08-04 19:30:08 -07001345}
1346
1347/**
Mike Christie5bb0b552006-04-06 21:26:46 -05001348 * iscsi_tcp_mtask_xmit - xmit management(immediate) task
Alex Aizman7ba24712005-08-04 19:30:08 -07001349 * @conn: iscsi connection
1350 * @mtask: task management task
1351 *
1352 * Notes:
1353 * The function can return -EAGAIN in which case caller must
1354 * call it again later, or recover. '0' return code means successful
1355 * xmit.
Alex Aizman7ba24712005-08-04 19:30:08 -07001356 **/
1357static int
Mike Christie5bb0b552006-04-06 21:26:46 -05001358iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
Alex Aizman7ba24712005-08-04 19:30:08 -07001359{
Mike Christie3219e522006-05-30 00:37:28 -05001360 int rc;
Alex Aizman7ba24712005-08-04 19:30:08 -07001361
Olaf Kircha8ac6312007-12-13 12:43:35 -06001362 /* Flush any pending data first. */
1363 rc = iscsi_tcp_flush(conn);
1364 if (rc < 0)
1365 return rc;
Alex Aizman7ba24712005-08-04 19:30:08 -07001366
Al Virob4377352007-02-09 16:39:40 +00001367 if (mtask->hdr->itt == RESERVED_ITT) {
Mike Christie5bb0b552006-04-06 21:26:46 -05001368 struct iscsi_session *session = conn->session;
1369
1370 spin_lock_bh(&session->lock);
Mike Christieb3a7ea82007-12-13 12:43:26 -06001371 iscsi_free_mgmt_task(conn, mtask);
Mike Christie5bb0b552006-04-06 21:26:46 -05001372 spin_unlock_bh(&session->lock);
1373 }
Olaf Kircha8ac6312007-12-13 12:43:35 -06001374
Alex Aizman7ba24712005-08-04 19:30:08 -07001375 return 0;
1376}
1377
Olaf Kircha8ac6312007-12-13 12:43:35 -06001378/*
Mike Christie218432c2007-05-30 12:57:17 -05001379 * iscsi_tcp_ctask_xmit - xmit normal PDU task
1380 * @conn: iscsi connection
1381 * @ctask: iscsi command task
1382 *
Olaf Kircha8ac6312007-12-13 12:43:35 -06001383 * We're expected to return 0 when everything was transmitted succesfully,
1384 * -EAGAIN if there's still data in the queue, or != 0 for any other kind
1385 * of error.
1386 */
Alex Aizman7ba24712005-08-04 19:30:08 -07001387static int
Mike Christie5bb0b552006-04-06 21:26:46 -05001388iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
Alex Aizman7ba24712005-08-04 19:30:08 -07001389{
Mike Christie5bb0b552006-04-06 21:26:46 -05001390 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
Olaf Kircha8ac6312007-12-13 12:43:35 -06001391 struct scsi_cmnd *sc = ctask->sc;
Boaz Harrosh94795b62008-04-18 10:11:53 -05001392 struct scsi_data_buffer *sdb = scsi_out(sc);
Alex Aizman7ba24712005-08-04 19:30:08 -07001393 int rc = 0;
1394
Olaf Kircha8ac6312007-12-13 12:43:35 -06001395flush:
1396 /* Flush any pending data first. */
1397 rc = iscsi_tcp_flush(conn);
1398 if (rc < 0)
Mike Christie218432c2007-05-30 12:57:17 -05001399 return rc;
Olaf Kircha8ac6312007-12-13 12:43:35 -06001400
1401 /* Are we done already? */
1402 if (sc->sc_data_direction != DMA_TO_DEVICE)
Mike Christie218432c2007-05-30 12:57:17 -05001403 return 0;
Alex Aizman7ba24712005-08-04 19:30:08 -07001404
Olaf Kircha8ac6312007-12-13 12:43:35 -06001405 if (ctask->unsol_count != 0) {
1406 struct iscsi_data *hdr = &tcp_ctask->unsol_dtask.hdr;
1407
1408 /* Prepare a header for the unsolicited PDU.
1409 * The amount of data we want to send will be
1410 * in ctask->data_count.
1411 * FIXME: return the data count instead.
1412 */
1413 iscsi_prep_unsolicit_data_pdu(ctask, hdr);
1414
1415 debug_tcp("unsol dout [itt 0x%x doff %d dlen %d]\n",
1416 ctask->itt, tcp_ctask->sent, ctask->data_count);
1417
1418 iscsi_tcp_send_hdr_prep(conn, hdr, sizeof(*hdr));
Boaz Harrosh94795b62008-04-18 10:11:53 -05001419 rc = iscsi_tcp_send_data_prep(conn, sdb->table.sgl,
1420 sdb->table.nents, tcp_ctask->sent,
Olaf Kircha8ac6312007-12-13 12:43:35 -06001421 ctask->data_count);
Alex Aizman7ba24712005-08-04 19:30:08 -07001422 if (rc)
Olaf Kircha8ac6312007-12-13 12:43:35 -06001423 goto fail;
1424 tcp_ctask->sent += ctask->data_count;
1425 ctask->unsol_count -= ctask->data_count;
1426 goto flush;
1427 } else {
1428 struct iscsi_session *session = conn->session;
1429 struct iscsi_r2t_info *r2t;
1430
1431 /* All unsolicited PDUs sent. Check for solicited PDUs.
1432 */
1433 spin_lock_bh(&session->lock);
1434 r2t = tcp_ctask->r2t;
1435 if (r2t != NULL) {
1436 /* Continue with this R2T? */
1437 if (!iscsi_solicit_data_cont(conn, ctask, r2t)) {
1438 debug_scsi(" done with r2t %p\n", r2t);
1439
1440 __kfifo_put(tcp_ctask->r2tpool.queue,
1441 (void*)&r2t, sizeof(void*));
1442 tcp_ctask->r2t = r2t = NULL;
1443 }
1444 }
1445
1446 if (r2t == NULL) {
1447 __kfifo_get(tcp_ctask->r2tqueue, (void*)&tcp_ctask->r2t,
1448 sizeof(void*));
1449 r2t = tcp_ctask->r2t;
1450 }
1451 spin_unlock_bh(&session->lock);
1452
1453 /* Waiting for more R2Ts to arrive. */
1454 if (r2t == NULL) {
1455 debug_tcp("no R2Ts yet\n");
1456 return 0;
1457 }
1458
1459 debug_scsi("sol dout %p [dsn %d itt 0x%x doff %d dlen %d]\n",
1460 r2t, r2t->solicit_datasn - 1, ctask->itt,
1461 r2t->data_offset + r2t->sent, r2t->data_count);
1462
1463 iscsi_tcp_send_hdr_prep(conn, &r2t->dtask.hdr,
1464 sizeof(struct iscsi_hdr));
1465
Boaz Harrosh94795b62008-04-18 10:11:53 -05001466 rc = iscsi_tcp_send_data_prep(conn, sdb->table.sgl,
1467 sdb->table.nents,
Olaf Kircha8ac6312007-12-13 12:43:35 -06001468 r2t->data_offset + r2t->sent,
1469 r2t->data_count);
1470 if (rc)
1471 goto fail;
1472 tcp_ctask->sent += r2t->data_count;
1473 r2t->sent += r2t->data_count;
1474 goto flush;
Alex Aizman7ba24712005-08-04 19:30:08 -07001475 }
Olaf Kircha8ac6312007-12-13 12:43:35 -06001476 return 0;
1477fail:
1478 iscsi_conn_failure(conn, rc);
1479 return -EIO;
Alex Aizman7ba24712005-08-04 19:30:08 -07001480}
1481
Mike Christie7b8631b2006-01-13 18:05:50 -06001482static struct iscsi_cls_conn *
Mike Christie5bb0b552006-04-06 21:26:46 -05001483iscsi_tcp_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
Alex Aizman7ba24712005-08-04 19:30:08 -07001484{
Mike Christie7b8631b2006-01-13 18:05:50 -06001485 struct iscsi_conn *conn;
1486 struct iscsi_cls_conn *cls_conn;
Mike Christie5bb0b552006-04-06 21:26:46 -05001487 struct iscsi_tcp_conn *tcp_conn;
Alex Aizman7ba24712005-08-04 19:30:08 -07001488
Mike Christie5bb0b552006-04-06 21:26:46 -05001489 cls_conn = iscsi_conn_setup(cls_session, conn_idx);
Mike Christie7b8631b2006-01-13 18:05:50 -06001490 if (!cls_conn)
1491 return NULL;
1492 conn = cls_conn->dd_data;
Mike Christie5bb0b552006-04-06 21:26:46 -05001493 /*
1494 * due to strange issues with iser these are not set
1495 * in iscsi_conn_setup
1496 */
Mike Christiebf32ed32007-02-28 17:32:17 -06001497 conn->max_recv_dlength = ISCSI_DEF_MAX_RECV_SEG_LEN;
Alex Aizman7ba24712005-08-04 19:30:08 -07001498
Mike Christie5bb0b552006-04-06 21:26:46 -05001499 tcp_conn = kzalloc(sizeof(*tcp_conn), GFP_KERNEL);
1500 if (!tcp_conn)
1501 goto tcp_conn_alloc_fail;
Alex Aizman7ba24712005-08-04 19:30:08 -07001502
Mike Christie5bb0b552006-04-06 21:26:46 -05001503 conn->dd_data = tcp_conn;
1504 tcp_conn->iscsi_conn = conn;
Alex Aizman7ba24712005-08-04 19:30:08 -07001505
James Bottomleyc9802cd2006-09-23 15:33:43 -05001506 tcp_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0,
1507 CRYPTO_ALG_ASYNC);
1508 tcp_conn->tx_hash.flags = 0;
Mike Christie322d7392008-01-31 13:36:52 -06001509 if (IS_ERR(tcp_conn->tx_hash.tfm))
Mike Christiedd8c0d92006-08-31 18:09:28 -04001510 goto free_tcp_conn;
1511
James Bottomleyc9802cd2006-09-23 15:33:43 -05001512 tcp_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0,
1513 CRYPTO_ALG_ASYNC);
1514 tcp_conn->rx_hash.flags = 0;
Mike Christie322d7392008-01-31 13:36:52 -06001515 if (IS_ERR(tcp_conn->rx_hash.tfm))
Mike Christiedd8c0d92006-08-31 18:09:28 -04001516 goto free_tx_tfm;
1517
Mike Christie7b8631b2006-01-13 18:05:50 -06001518 return cls_conn;
Alex Aizman7ba24712005-08-04 19:30:08 -07001519
Mike Christiedd8c0d92006-08-31 18:09:28 -04001520free_tx_tfm:
James Bottomleyc9802cd2006-09-23 15:33:43 -05001521 crypto_free_hash(tcp_conn->tx_hash.tfm);
Mike Christiedd8c0d92006-08-31 18:09:28 -04001522free_tcp_conn:
Mike Christie322d7392008-01-31 13:36:52 -06001523 iscsi_conn_printk(KERN_ERR, conn,
1524 "Could not create connection due to crc32c "
1525 "loading error. Make sure the crc32c "
1526 "module is built as a module or into the "
1527 "kernel\n");
Mike Christiedd8c0d92006-08-31 18:09:28 -04001528 kfree(tcp_conn);
Mike Christie5bb0b552006-04-06 21:26:46 -05001529tcp_conn_alloc_fail:
1530 iscsi_conn_teardown(cls_conn);
Mike Christie7b8631b2006-01-13 18:05:50 -06001531 return NULL;
Alex Aizman7ba24712005-08-04 19:30:08 -07001532}
1533
1534static void
Mike Christie1c834692006-07-24 15:47:26 -05001535iscsi_tcp_release_conn(struct iscsi_conn *conn)
1536{
Mike Christie22236962007-05-30 12:57:24 -05001537 struct iscsi_session *session = conn->session;
Mike Christie1c834692006-07-24 15:47:26 -05001538 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
Mike Christie22236962007-05-30 12:57:24 -05001539 struct socket *sock = tcp_conn->sock;
Mike Christie1c834692006-07-24 15:47:26 -05001540
Mike Christie22236962007-05-30 12:57:24 -05001541 if (!sock)
Mike Christie1c834692006-07-24 15:47:26 -05001542 return;
1543
Mike Christie22236962007-05-30 12:57:24 -05001544 sock_hold(sock->sk);
Mike Christie1c834692006-07-24 15:47:26 -05001545 iscsi_conn_restore_callbacks(tcp_conn);
Mike Christie22236962007-05-30 12:57:24 -05001546 sock_put(sock->sk);
Mike Christie1c834692006-07-24 15:47:26 -05001547
Mike Christie22236962007-05-30 12:57:24 -05001548 spin_lock_bh(&session->lock);
Mike Christie1c834692006-07-24 15:47:26 -05001549 tcp_conn->sock = NULL;
1550 conn->recv_lock = NULL;
Mike Christie22236962007-05-30 12:57:24 -05001551 spin_unlock_bh(&session->lock);
1552 sockfd_put(sock);
Mike Christie1c834692006-07-24 15:47:26 -05001553}
1554
1555static void
Mike Christie5bb0b552006-04-06 21:26:46 -05001556iscsi_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
Alex Aizman7ba24712005-08-04 19:30:08 -07001557{
Mike Christie7b8631b2006-01-13 18:05:50 -06001558 struct iscsi_conn *conn = cls_conn->dd_data;
Mike Christie5bb0b552006-04-06 21:26:46 -05001559 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
Alex Aizman7ba24712005-08-04 19:30:08 -07001560
Mike Christie1c834692006-07-24 15:47:26 -05001561 iscsi_tcp_release_conn(conn);
Mike Christie5bb0b552006-04-06 21:26:46 -05001562 iscsi_conn_teardown(cls_conn);
Alex Aizman7ba24712005-08-04 19:30:08 -07001563
Pete Wyckoff534284a2006-11-08 15:58:31 -06001564 if (tcp_conn->tx_hash.tfm)
1565 crypto_free_hash(tcp_conn->tx_hash.tfm);
1566 if (tcp_conn->rx_hash.tfm)
1567 crypto_free_hash(tcp_conn->rx_hash.tfm);
Alex Aizman7ba24712005-08-04 19:30:08 -07001568
Mike Christie5bb0b552006-04-06 21:26:46 -05001569 kfree(tcp_conn);
Alex Aizman7ba24712005-08-04 19:30:08 -07001570}
1571
Mike Christie1c834692006-07-24 15:47:26 -05001572static void
1573iscsi_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1574{
1575 struct iscsi_conn *conn = cls_conn->dd_data;
1576
1577 iscsi_conn_stop(cls_conn, flag);
1578 iscsi_tcp_release_conn(conn);
1579}
1580
Mike Christie22236962007-05-30 12:57:24 -05001581static int iscsi_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock,
1582 char *buf, int *port,
1583 int (*getname)(struct socket *, struct sockaddr *,
1584 int *addrlen))
1585{
1586 struct sockaddr_storage *addr;
1587 struct sockaddr_in6 *sin6;
1588 struct sockaddr_in *sin;
1589 int rc = 0, len;
1590
Al Viroa9204872007-07-20 16:03:40 +01001591 addr = kmalloc(sizeof(*addr), GFP_KERNEL);
Mike Christie22236962007-05-30 12:57:24 -05001592 if (!addr)
1593 return -ENOMEM;
1594
1595 if (getname(sock, (struct sockaddr *) addr, &len)) {
1596 rc = -ENODEV;
1597 goto free_addr;
1598 }
1599
1600 switch (addr->ss_family) {
1601 case AF_INET:
1602 sin = (struct sockaddr_in *)addr;
1603 spin_lock_bh(&conn->session->lock);
1604 sprintf(buf, NIPQUAD_FMT, NIPQUAD(sin->sin_addr.s_addr));
1605 *port = be16_to_cpu(sin->sin_port);
1606 spin_unlock_bh(&conn->session->lock);
1607 break;
1608 case AF_INET6:
1609 sin6 = (struct sockaddr_in6 *)addr;
1610 spin_lock_bh(&conn->session->lock);
1611 sprintf(buf, NIP6_FMT, NIP6(sin6->sin6_addr));
1612 *port = be16_to_cpu(sin6->sin6_port);
1613 spin_unlock_bh(&conn->session->lock);
1614 break;
1615 }
1616free_addr:
1617 kfree(addr);
1618 return rc;
1619}
1620
Alex Aizman7ba24712005-08-04 19:30:08 -07001621static int
Mike Christie5bb0b552006-04-06 21:26:46 -05001622iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
Or Gerlitz264faaa2006-05-02 19:46:36 -05001623 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
Mike Christie5bb0b552006-04-06 21:26:46 -05001624 int is_leading)
Alex Aizman7ba24712005-08-04 19:30:08 -07001625{
Mike Christie5bb0b552006-04-06 21:26:46 -05001626 struct iscsi_conn *conn = cls_conn->dd_data;
1627 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
Alex Aizman7ba24712005-08-04 19:30:08 -07001628 struct sock *sk;
1629 struct socket *sock;
1630 int err;
1631
1632 /* lookup for existing socket */
Or Gerlitz264faaa2006-05-02 19:46:36 -05001633 sock = sockfd_lookup((int)transport_eph, &err);
Alex Aizman7ba24712005-08-04 19:30:08 -07001634 if (!sock) {
Mike Christie322d7392008-01-31 13:36:52 -06001635 iscsi_conn_printk(KERN_ERR, conn,
1636 "sockfd_lookup failed %d\n", err);
Alex Aizman7ba24712005-08-04 19:30:08 -07001637 return -EEXIST;
1638 }
Mike Christie22236962007-05-30 12:57:24 -05001639 /*
1640 * copy these values now because if we drop the session
1641 * userspace may still want to query the values since we will
1642 * be using them for the reconnect
1643 */
1644 err = iscsi_tcp_get_addr(conn, sock, conn->portal_address,
1645 &conn->portal_port, kernel_getpeername);
1646 if (err)
1647 goto free_socket;
1648
1649 err = iscsi_tcp_get_addr(conn, sock, conn->local_address,
1650 &conn->local_port, kernel_getsockname);
1651 if (err)
1652 goto free_socket;
Alex Aizman7ba24712005-08-04 19:30:08 -07001653
Mike Christie5bb0b552006-04-06 21:26:46 -05001654 err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
1655 if (err)
Mike Christie22236962007-05-30 12:57:24 -05001656 goto free_socket;
Alex Aizman7ba24712005-08-04 19:30:08 -07001657
Mike Christie67a61112006-05-30 00:37:20 -05001658 /* bind iSCSI connection and socket */
1659 tcp_conn->sock = sock;
Alex Aizman7ba24712005-08-04 19:30:08 -07001660
Mike Christie67a61112006-05-30 00:37:20 -05001661 /* setup Socket parameters */
1662 sk = sock->sk;
1663 sk->sk_reuse = 1;
1664 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
1665 sk->sk_allocation = GFP_ATOMIC;
Alex Aizman7ba24712005-08-04 19:30:08 -07001666
Mike Christie67a61112006-05-30 00:37:20 -05001667 /* FIXME: disable Nagle's algorithm */
Alex Aizman7ba24712005-08-04 19:30:08 -07001668
Mike Christie67a61112006-05-30 00:37:20 -05001669 /*
1670 * Intercept TCP callbacks for sendfile like receive
1671 * processing.
1672 */
1673 conn->recv_lock = &sk->sk_callback_lock;
1674 iscsi_conn_set_callbacks(conn);
1675 tcp_conn->sendpage = tcp_conn->sock->ops->sendpage;
1676 /*
1677 * set receive state machine into initial state
1678 */
Olaf Kirchda32dd62007-12-13 12:43:21 -06001679 iscsi_tcp_hdr_recv_prep(tcp_conn);
Alex Aizman7ba24712005-08-04 19:30:08 -07001680 return 0;
Mike Christie22236962007-05-30 12:57:24 -05001681
1682free_socket:
1683 sockfd_put(sock);
1684 return err;
Alex Aizman7ba24712005-08-04 19:30:08 -07001685}
1686
Mike Christie5bb0b552006-04-06 21:26:46 -05001687/* called with host lock */
Mike Christie30a6c652006-04-06 21:13:39 -05001688static void
Olaf Kircha8ac6312007-12-13 12:43:35 -06001689iscsi_tcp_mtask_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
Mike Christie30a6c652006-04-06 21:13:39 -05001690{
Olaf Kircha8ac6312007-12-13 12:43:35 -06001691 debug_scsi("mtask deq [cid %d itt 0x%x]\n", conn->id, mtask->itt);
1692
1693 /* Prepare PDU, optionally w/ immediate data */
1694 iscsi_tcp_send_hdr_prep(conn, mtask->hdr, sizeof(*mtask->hdr));
1695
1696 /* If we have immediate data, attach a payload */
1697 if (mtask->data_count)
1698 iscsi_tcp_send_linear_data_prepare(conn, mtask->data,
1699 mtask->data_count);
Alex Aizman7ba24712005-08-04 19:30:08 -07001700}
1701
1702static int
1703iscsi_r2tpool_alloc(struct iscsi_session *session)
1704{
1705 int i;
1706 int cmd_i;
1707
1708 /*
1709 * initialize per-task: R2T pool and xmit queue
1710 */
1711 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1712 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
Mike Christie5bb0b552006-04-06 21:26:46 -05001713 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
Alex Aizman7ba24712005-08-04 19:30:08 -07001714
1715 /*
1716 * pre-allocated x4 as much r2ts to handle race when
1717 * target acks DataOut faster than we data_xmit() queues
1718 * could replenish r2tqueue.
1719 */
1720
1721 /* R2T pool */
Olaf Kirch63203772007-12-13 12:43:25 -06001722 if (iscsi_pool_init(&tcp_ctask->r2tpool, session->max_r2t * 4, NULL,
Mike Christie5bb0b552006-04-06 21:26:46 -05001723 sizeof(struct iscsi_r2t_info))) {
Alex Aizman7ba24712005-08-04 19:30:08 -07001724 goto r2t_alloc_fail;
1725 }
1726
1727 /* R2T xmit queue */
Mike Christie5bb0b552006-04-06 21:26:46 -05001728 tcp_ctask->r2tqueue = kfifo_alloc(
Alex Aizman7ba24712005-08-04 19:30:08 -07001729 session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
Mike Christie5bb0b552006-04-06 21:26:46 -05001730 if (tcp_ctask->r2tqueue == ERR_PTR(-ENOMEM)) {
Olaf Kirch63203772007-12-13 12:43:25 -06001731 iscsi_pool_free(&tcp_ctask->r2tpool);
Alex Aizman7ba24712005-08-04 19:30:08 -07001732 goto r2t_alloc_fail;
1733 }
Alex Aizman7ba24712005-08-04 19:30:08 -07001734 }
1735
1736 return 0;
1737
1738r2t_alloc_fail:
1739 for (i = 0; i < cmd_i; i++) {
Mike Christie5bb0b552006-04-06 21:26:46 -05001740 struct iscsi_cmd_task *ctask = session->cmds[i];
1741 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1742
Mike Christie5bb0b552006-04-06 21:26:46 -05001743 kfifo_free(tcp_ctask->r2tqueue);
Olaf Kirch63203772007-12-13 12:43:25 -06001744 iscsi_pool_free(&tcp_ctask->r2tpool);
Alex Aizman7ba24712005-08-04 19:30:08 -07001745 }
1746 return -ENOMEM;
1747}
1748
1749static void
1750iscsi_r2tpool_free(struct iscsi_session *session)
1751{
1752 int i;
1753
1754 for (i = 0; i < session->cmds_max; i++) {
Mike Christie5bb0b552006-04-06 21:26:46 -05001755 struct iscsi_cmd_task *ctask = session->cmds[i];
1756 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1757
Mike Christie5bb0b552006-04-06 21:26:46 -05001758 kfifo_free(tcp_ctask->r2tqueue);
Olaf Kirch63203772007-12-13 12:43:25 -06001759 iscsi_pool_free(&tcp_ctask->r2tpool);
Alex Aizman7ba24712005-08-04 19:30:08 -07001760 }
1761}
1762
Alex Aizman7ba24712005-08-04 19:30:08 -07001763static int
Mike Christie7b7232f2006-02-01 21:06:49 -06001764iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
Mike Christie5c75b7f2006-06-28 12:00:26 -05001765 char *buf, int buflen)
Alex Aizman7ba24712005-08-04 19:30:08 -07001766{
Mike Christie7b7232f2006-02-01 21:06:49 -06001767 struct iscsi_conn *conn = cls_conn->dd_data;
Alex Aizman7ba24712005-08-04 19:30:08 -07001768 struct iscsi_session *session = conn->session;
Mike Christie5bb0b552006-04-06 21:26:46 -05001769 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
Mike Christie5c75b7f2006-06-28 12:00:26 -05001770 int value;
Alex Aizman7ba24712005-08-04 19:30:08 -07001771
Alex Aizman7ba24712005-08-04 19:30:08 -07001772 switch(param) {
Alex Aizman7ba24712005-08-04 19:30:08 -07001773 case ISCSI_PARAM_HDRDGST_EN:
Mike Christie5c75b7f2006-06-28 12:00:26 -05001774 iscsi_set_param(cls_conn, param, buf, buflen);
Alex Aizman7ba24712005-08-04 19:30:08 -07001775 break;
1776 case ISCSI_PARAM_DATADGST_EN:
Mike Christie5c75b7f2006-06-28 12:00:26 -05001777 iscsi_set_param(cls_conn, param, buf, buflen);
Mike Christie5bb0b552006-04-06 21:26:46 -05001778 tcp_conn->sendpage = conn->datadgst_en ?
1779 sock_no_sendpage : tcp_conn->sock->ops->sendpage;
Alex Aizman7ba24712005-08-04 19:30:08 -07001780 break;
Alex Aizman7ba24712005-08-04 19:30:08 -07001781 case ISCSI_PARAM_MAX_R2T:
Mike Christie5c75b7f2006-06-28 12:00:26 -05001782 sscanf(buf, "%d", &value);
Mike Christiedf93ffc2007-12-13 12:43:42 -06001783 if (value <= 0 || !is_power_of_2(value))
1784 return -EINVAL;
1785 if (session->max_r2t == value)
Alex Aizman7ba24712005-08-04 19:30:08 -07001786 break;
1787 iscsi_r2tpool_free(session);
Mike Christie5c75b7f2006-06-28 12:00:26 -05001788 iscsi_set_param(cls_conn, param, buf, buflen);
Alex Aizman7ba24712005-08-04 19:30:08 -07001789 if (iscsi_r2tpool_alloc(session))
1790 return -ENOMEM;
1791 break;
Alex Aizman7ba24712005-08-04 19:30:08 -07001792 default:
Mike Christie5c75b7f2006-06-28 12:00:26 -05001793 return iscsi_set_param(cls_conn, param, buf, buflen);
Alex Aizman7ba24712005-08-04 19:30:08 -07001794 }
1795
1796 return 0;
1797}
1798
1799static int
Mike Christie5c75b7f2006-06-28 12:00:26 -05001800iscsi_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
1801 enum iscsi_param param, char *buf)
Mike Christie7b8631b2006-01-13 18:05:50 -06001802{
Mike Christie7b7232f2006-02-01 21:06:49 -06001803 struct iscsi_conn *conn = cls_conn->dd_data;
Mike Christie5c75b7f2006-06-28 12:00:26 -05001804 int len;
Mike Christie7b8631b2006-01-13 18:05:50 -06001805
1806 switch(param) {
Mike Christiefd7255f2006-04-06 21:13:36 -05001807 case ISCSI_PARAM_CONN_PORT:
Mike Christie22236962007-05-30 12:57:24 -05001808 spin_lock_bh(&conn->session->lock);
1809 len = sprintf(buf, "%hu\n", conn->portal_port);
1810 spin_unlock_bh(&conn->session->lock);
Mike Christie8d2860b2006-05-02 19:46:47 -05001811 break;
Mike Christiefd7255f2006-04-06 21:13:36 -05001812 case ISCSI_PARAM_CONN_ADDRESS:
Mike Christie22236962007-05-30 12:57:24 -05001813 spin_lock_bh(&conn->session->lock);
1814 len = sprintf(buf, "%s\n", conn->portal_address);
1815 spin_unlock_bh(&conn->session->lock);
Mike Christiefd7255f2006-04-06 21:13:36 -05001816 break;
1817 default:
Mike Christie5c75b7f2006-06-28 12:00:26 -05001818 return iscsi_conn_get_param(cls_conn, param, buf);
Mike Christiefd7255f2006-04-06 21:13:36 -05001819 }
1820
1821 return len;
1822}
1823
Mike Christie22236962007-05-30 12:57:24 -05001824static int
1825iscsi_tcp_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
1826 char *buf)
1827{
1828 struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1829 int len;
1830
1831 switch (param) {
1832 case ISCSI_HOST_PARAM_IPADDRESS:
1833 spin_lock_bh(&session->lock);
1834 if (!session->leadconn)
1835 len = -ENODEV;
1836 else
1837 len = sprintf(buf, "%s\n",
1838 session->leadconn->local_address);
1839 spin_unlock_bh(&session->lock);
1840 break;
1841 default:
1842 return iscsi_host_get_param(shost, param, buf);
1843 }
1844 return len;
1845}
1846
Alex Aizman7ba24712005-08-04 19:30:08 -07001847static void
Mike Christie7b7232f2006-02-01 21:06:49 -06001848iscsi_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
Alex Aizman7ba24712005-08-04 19:30:08 -07001849{
Mike Christie7b7232f2006-02-01 21:06:49 -06001850 struct iscsi_conn *conn = cls_conn->dd_data;
Mike Christie5bb0b552006-04-06 21:26:46 -05001851 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
Alex Aizman7ba24712005-08-04 19:30:08 -07001852
1853 stats->txdata_octets = conn->txdata_octets;
1854 stats->rxdata_octets = conn->rxdata_octets;
1855 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
1856 stats->dataout_pdus = conn->dataout_pdus_cnt;
1857 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
1858 stats->datain_pdus = conn->datain_pdus_cnt;
1859 stats->r2t_pdus = conn->r2t_pdus_cnt;
1860 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
1861 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
1862 stats->custom_length = 3;
1863 strcpy(stats->custom[0].desc, "tx_sendpage_failures");
Mike Christie5bb0b552006-04-06 21:26:46 -05001864 stats->custom[0].value = tcp_conn->sendpage_failures_cnt;
Alex Aizman7ba24712005-08-04 19:30:08 -07001865 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
Mike Christie5bb0b552006-04-06 21:26:46 -05001866 stats->custom[1].value = tcp_conn->discontiguous_hdr_cnt;
Alex Aizman7ba24712005-08-04 19:30:08 -07001867 strcpy(stats->custom[2].desc, "eh_abort_cnt");
1868 stats->custom[2].value = conn->eh_abort_cnt;
1869}
1870
Mike Christie5bb0b552006-04-06 21:26:46 -05001871static struct iscsi_cls_session *
1872iscsi_tcp_session_create(struct iscsi_transport *iscsit,
1873 struct scsi_transport_template *scsit,
Mike Christie15482712007-05-30 12:57:19 -05001874 uint16_t cmds_max, uint16_t qdepth,
Mike Christie5bb0b552006-04-06 21:26:46 -05001875 uint32_t initial_cmdsn, uint32_t *hostno)
Alex Aizman7ba24712005-08-04 19:30:08 -07001876{
Mike Christie5bb0b552006-04-06 21:26:46 -05001877 struct iscsi_cls_session *cls_session;
1878 struct iscsi_session *session;
1879 uint32_t hn;
1880 int cmd_i;
Alex Aizman7ba24712005-08-04 19:30:08 -07001881
Mike Christie15482712007-05-30 12:57:19 -05001882 cls_session = iscsi_session_setup(iscsit, scsit, cmds_max, qdepth,
Mike Christie5bb0b552006-04-06 21:26:46 -05001883 sizeof(struct iscsi_tcp_cmd_task),
1884 sizeof(struct iscsi_tcp_mgmt_task),
1885 initial_cmdsn, &hn);
1886 if (!cls_session)
1887 return NULL;
1888 *hostno = hn;
Alex Aizman7ba24712005-08-04 19:30:08 -07001889
Mike Christie5bb0b552006-04-06 21:26:46 -05001890 session = class_to_transport_session(cls_session);
1891 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1892 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1893 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1894
Boaz Harrosh004d6532007-12-13 12:43:23 -06001895 ctask->hdr = &tcp_ctask->hdr.cmd_hdr;
1896 ctask->hdr_max = sizeof(tcp_ctask->hdr) - ISCSI_DIGEST_SIZE;
Mike Christie5bb0b552006-04-06 21:26:46 -05001897 }
1898
1899 for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1900 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1901 struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
1902
Olaf Kircha8ac6312007-12-13 12:43:35 -06001903 mtask->hdr = (struct iscsi_hdr *) &tcp_mtask->hdr;
Mike Christie5bb0b552006-04-06 21:26:46 -05001904 }
1905
1906 if (iscsi_r2tpool_alloc(class_to_transport_session(cls_session)))
1907 goto r2tpool_alloc_fail;
1908
1909 return cls_session;
1910
1911r2tpool_alloc_fail:
1912 iscsi_session_teardown(cls_session);
1913 return NULL;
Alex Aizman7ba24712005-08-04 19:30:08 -07001914}
1915
Mike Christie5bb0b552006-04-06 21:26:46 -05001916static void iscsi_tcp_session_destroy(struct iscsi_cls_session *cls_session)
1917{
Mike Christie5bb0b552006-04-06 21:26:46 -05001918 iscsi_r2tpool_free(class_to_transport_session(cls_session));
1919 iscsi_session_teardown(cls_session);
1920}
1921
Mike Christied1d81c02007-05-30 12:57:21 -05001922static int iscsi_tcp_slave_configure(struct scsi_device *sdev)
1923{
Mike Christieb6d44fe2007-07-26 12:46:47 -05001924 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY);
Mike Christied1d81c02007-05-30 12:57:21 -05001925 blk_queue_dma_alignment(sdev->request_queue, 0);
1926 return 0;
1927}
1928
Mike Christie5bb0b552006-04-06 21:26:46 -05001929static struct scsi_host_template iscsi_sht = {
Mike Christie79743922007-07-26 12:46:46 -05001930 .module = THIS_MODULE,
Mike Christief4246b32006-07-24 15:47:54 -05001931 .name = "iSCSI Initiator over TCP/IP",
Mike Christie5bb0b552006-04-06 21:26:46 -05001932 .queuecommand = iscsi_queuecommand,
1933 .change_queue_depth = iscsi_change_queue_depth,
Mike Christie15482712007-05-30 12:57:19 -05001934 .can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1,
Mike Christie66bbe0c2007-12-13 12:43:39 -06001935 .sg_tablesize = 4096,
Mike Christie8231f0e2007-02-28 17:32:20 -06001936 .max_sectors = 0xFFFF,
Mike Christie5bb0b552006-04-06 21:26:46 -05001937 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
1938 .eh_abort_handler = iscsi_eh_abort,
Mike Christie843c0a82007-12-13 12:43:20 -06001939 .eh_device_reset_handler= iscsi_eh_device_reset,
Mike Christie5bb0b552006-04-06 21:26:46 -05001940 .eh_host_reset_handler = iscsi_eh_host_reset,
1941 .use_clustering = DISABLE_CLUSTERING,
Mike Christied1d81c02007-05-30 12:57:21 -05001942 .slave_configure = iscsi_tcp_slave_configure,
Mike Christie5bb0b552006-04-06 21:26:46 -05001943 .proc_name = "iscsi_tcp",
1944 .this_id = -1,
1945};
1946
Alex Aizman7ba24712005-08-04 19:30:08 -07001947static struct iscsi_transport iscsi_tcp_transport = {
1948 .owner = THIS_MODULE,
1949 .name = "tcp",
1950 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
1951 | CAP_DATADGST,
Mike Christiefd7255f2006-04-06 21:13:36 -05001952 .param_mask = ISCSI_MAX_RECV_DLENGTH |
1953 ISCSI_MAX_XMIT_DLENGTH |
1954 ISCSI_HDRDGST_EN |
1955 ISCSI_DATADGST_EN |
1956 ISCSI_INITIAL_R2T_EN |
1957 ISCSI_MAX_R2T |
1958 ISCSI_IMM_DATA_EN |
1959 ISCSI_FIRST_BURST |
1960 ISCSI_MAX_BURST |
1961 ISCSI_PDU_INORDER_EN |
1962 ISCSI_DATASEQ_INORDER_EN |
1963 ISCSI_ERL |
1964 ISCSI_CONN_PORT |
Mike Christie8d2860b2006-05-02 19:46:47 -05001965 ISCSI_CONN_ADDRESS |
Mike Christie5c75b7f2006-06-28 12:00:26 -05001966 ISCSI_EXP_STATSN |
1967 ISCSI_PERSISTENT_PORT |
1968 ISCSI_PERSISTENT_ADDRESS |
Mike Christieb2c64162007-05-30 12:57:16 -05001969 ISCSI_TARGET_NAME | ISCSI_TPGT |
1970 ISCSI_USERNAME | ISCSI_PASSWORD |
Mike Christie843c0a82007-12-13 12:43:20 -06001971 ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN |
Mike Christief6d51802007-12-13 12:43:30 -06001972 ISCSI_FAST_ABORT | ISCSI_ABORT_TMO |
1973 ISCSI_LU_RESET_TMO |
1974 ISCSI_PING_TMO | ISCSI_RECV_TMO,
Mike Christie22236962007-05-30 12:57:24 -05001975 .host_param_mask = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
Mike Christied8196ed2007-05-30 12:57:25 -05001976 ISCSI_HOST_INITIATOR_NAME |
1977 ISCSI_HOST_NETDEV_NAME,
Alex Aizman7ba24712005-08-04 19:30:08 -07001978 .host_template = &iscsi_sht,
Mike Christie7b8631b2006-01-13 18:05:50 -06001979 .conndata_size = sizeof(struct iscsi_conn),
Alex Aizman7ba24712005-08-04 19:30:08 -07001980 .max_conn = 1,
Mike Christie66bbe0c2007-12-13 12:43:39 -06001981 .max_cmd_len = 16,
Mike Christie5bb0b552006-04-06 21:26:46 -05001982 /* session management */
1983 .create_session = iscsi_tcp_session_create,
1984 .destroy_session = iscsi_tcp_session_destroy,
1985 /* connection management */
1986 .create_conn = iscsi_tcp_conn_create,
1987 .bind_conn = iscsi_tcp_conn_bind,
1988 .destroy_conn = iscsi_tcp_conn_destroy,
Alex Aizman7ba24712005-08-04 19:30:08 -07001989 .set_param = iscsi_conn_set_param,
Mike Christie5c75b7f2006-06-28 12:00:26 -05001990 .get_conn_param = iscsi_tcp_conn_get_param,
Mike Christie7b8631b2006-01-13 18:05:50 -06001991 .get_session_param = iscsi_session_get_param,
Alex Aizman7ba24712005-08-04 19:30:08 -07001992 .start_conn = iscsi_conn_start,
Mike Christie1c834692006-07-24 15:47:26 -05001993 .stop_conn = iscsi_tcp_conn_stop,
Mike Christie0801c242007-05-30 12:57:12 -05001994 /* iscsi host params */
Mike Christie22236962007-05-30 12:57:24 -05001995 .get_host_param = iscsi_tcp_host_get_param,
Mike Christie0801c242007-05-30 12:57:12 -05001996 .set_host_param = iscsi_host_set_param,
Mike Christie5bb0b552006-04-06 21:26:46 -05001997 /* IO */
Alex Aizman7ba24712005-08-04 19:30:08 -07001998 .send_pdu = iscsi_conn_send_pdu,
1999 .get_stats = iscsi_conn_get_stats,
Olaf Kircha8ac6312007-12-13 12:43:35 -06002000 .init_cmd_task = iscsi_tcp_ctask_init,
2001 .init_mgmt_task = iscsi_tcp_mtask_init,
Mike Christie5bb0b552006-04-06 21:26:46 -05002002 .xmit_cmd_task = iscsi_tcp_ctask_xmit,
2003 .xmit_mgmt_task = iscsi_tcp_mtask_xmit,
2004 .cleanup_cmd_task = iscsi_tcp_cleanup_ctask,
2005 /* recovery */
Mike Christie30a6c652006-04-06 21:13:39 -05002006 .session_recovery_timedout = iscsi_session_recovery_timedout,
Alex Aizman7ba24712005-08-04 19:30:08 -07002007};
2008
2009static int __init
2010iscsi_tcp_init(void)
2011{
Alex Aizman7ba24712005-08-04 19:30:08 -07002012 if (iscsi_max_lun < 1) {
Or Gerlitzbe2df722006-05-02 19:46:43 -05002013 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
2014 iscsi_max_lun);
Alex Aizman7ba24712005-08-04 19:30:08 -07002015 return -EINVAL;
2016 }
2017 iscsi_tcp_transport.max_lun = iscsi_max_lun;
2018
Mike Christie7b8631b2006-01-13 18:05:50 -06002019 if (!iscsi_register_transport(&iscsi_tcp_transport))
Mike Christieffbfe922006-05-18 20:31:36 -05002020 return -ENODEV;
Alex Aizman7ba24712005-08-04 19:30:08 -07002021
Mike Christie7b8631b2006-01-13 18:05:50 -06002022 return 0;
Alex Aizman7ba24712005-08-04 19:30:08 -07002023}
2024
2025static void __exit
2026iscsi_tcp_exit(void)
2027{
2028 iscsi_unregister_transport(&iscsi_tcp_transport);
Alex Aizman7ba24712005-08-04 19:30:08 -07002029}
2030
2031module_init(iscsi_tcp_init);
2032module_exit(iscsi_tcp_exit);