2 * iSCSI Initiator over TCP/IP Data-Path
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
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.
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.
20 * See the file COPYING included with this distribution for more details.
29 #include <linux/types.h>
30 #include <linux/list.h>
31 #include <linux/inet.h>
32 #include <linux/file.h>
33 #include <linux/blkdev.h>
34 #include <linux/crypto.h>
35 #include <linux/delay.h>
36 #include <linux/kfifo.h>
37 #include <linux/scatterlist.h>
39 #include <scsi/scsi_cmnd.h>
40 #include <scsi/scsi_device.h>
41 #include <scsi/scsi_host.h>
42 #include <scsi/scsi.h>
43 #include <scsi/scsi_transport_iscsi.h>
45 #include "iscsi_tcp.h"
47 MODULE_AUTHOR("Dmitry Yusupov <dmitry_yus@yahoo.com>, "
48 "Alex Aizman <itn780@yahoo.com>");
49 MODULE_DESCRIPTION("iSCSI/TCP data-path");
50 MODULE_LICENSE("GPL");
55 #define debug_tcp(fmt...) printk(KERN_INFO "tcp: " fmt)
57 #define debug_tcp(fmt...)
67 static struct scsi_transport_template *iscsi_tcp_scsi_transport;
68 static struct scsi_host_template iscsi_sht;
69 static struct iscsi_transport iscsi_tcp_transport;
71 static unsigned int iscsi_max_lun = 512;
72 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
74 static int iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
75 struct iscsi_segment *segment);
78 * Scatterlist handling: inside the iscsi_segment, we
79 * remember an index into the scatterlist, and set data/size
80 * to the current scatterlist entry. For highmem pages, we
83 * Note that the page is unmapped when we return from
84 * TCP's data_ready handler, so we may end up mapping and
85 * unmapping the same page repeatedly. The whole reason
86 * for this is that we shouldn't keep the page mapped
87 * outside the softirq.
91 * iscsi_tcp_segment_init_sg - init indicated scatterlist entry
92 * @segment: the buffer object
94 * @offset: byte offset into that sg entry
96 * This function sets up the segment so that subsequent
97 * data is copied to the indicated sg entry, at the given
101 iscsi_tcp_segment_init_sg(struct iscsi_segment *segment,
102 struct scatterlist *sg, unsigned int offset)
105 segment->sg_offset = offset;
106 segment->size = min(sg->length - offset,
107 segment->total_size - segment->total_copied);
108 segment->data = NULL;
112 * iscsi_tcp_segment_map - map the current S/G page
113 * @segment: iscsi_segment
114 * @recv: 1 if called from recv path
116 * We only need to possibly kmap data if scatter lists are being used,
117 * because the iscsi passthrough and internal IO paths will never use high
121 iscsi_tcp_segment_map(struct iscsi_segment *segment, int recv)
123 struct scatterlist *sg;
125 if (segment->data != NULL || !segment->sg)
129 BUG_ON(segment->sg_mapped);
130 BUG_ON(sg->length == 0);
133 * If the page count is greater than one it is ok to send
134 * to the network layer's zero copy send path. If not we
135 * have to go the slow sendmsg path. We always map for the
138 if (page_count(sg_page(sg)) >= 1 && !recv)
141 debug_tcp("iscsi_tcp_segment_map %s %p\n", recv ? "recv" : "xmit",
143 segment->sg_mapped = kmap_atomic(sg_page(sg), KM_SOFTIRQ0);
144 segment->data = segment->sg_mapped + sg->offset + segment->sg_offset;
148 iscsi_tcp_segment_unmap(struct iscsi_segment *segment)
150 debug_tcp("iscsi_tcp_segment_unmap %p\n", segment);
152 if (segment->sg_mapped) {
153 debug_tcp("iscsi_tcp_segment_unmap valid\n");
154 kunmap_atomic(segment->sg_mapped, KM_SOFTIRQ0);
155 segment->sg_mapped = NULL;
156 segment->data = NULL;
161 * Splice the digest buffer into the buffer
164 iscsi_tcp_segment_splice_digest(struct iscsi_segment *segment, void *digest)
166 segment->data = digest;
167 segment->digest_len = ISCSI_DIGEST_SIZE;
168 segment->total_size += ISCSI_DIGEST_SIZE;
169 segment->size = ISCSI_DIGEST_SIZE;
172 segment->hash = NULL;
176 * iscsi_tcp_segment_done - check whether the segment is complete
177 * @segment: iscsi segment to check
178 * @recv: set to one of this is called from the recv path
179 * @copied: number of bytes copied
181 * Check if we're done receiving this segment. If the receive
182 * buffer is full but we expect more data, move on to the
183 * next entry in the scatterlist.
185 * If the amount of data we received isn't a multiple of 4,
186 * we will transparently receive the pad bytes, too.
188 * This function must be re-entrant.
191 iscsi_tcp_segment_done(struct iscsi_segment *segment, int recv, unsigned copied)
193 static unsigned char padbuf[ISCSI_PAD_LEN];
194 struct scatterlist sg;
197 debug_tcp("copied %u %u size %u %s\n", segment->copied, copied,
198 segment->size, recv ? "recv" : "xmit");
199 if (segment->hash && copied) {
201 * If a segment is kmapd we must unmap it before sending
202 * to the crypto layer since that will try to kmap it again.
204 iscsi_tcp_segment_unmap(segment);
206 if (!segment->data) {
207 sg_init_table(&sg, 1);
208 sg_set_page(&sg, sg_page(segment->sg), copied,
209 segment->copied + segment->sg_offset +
210 segment->sg->offset);
212 sg_init_one(&sg, segment->data + segment->copied,
214 crypto_hash_update(segment->hash, &sg, copied);
217 segment->copied += copied;
218 if (segment->copied < segment->size) {
219 iscsi_tcp_segment_map(segment, recv);
223 segment->total_copied += segment->copied;
227 /* Unmap the current scatterlist page, if there is one. */
228 iscsi_tcp_segment_unmap(segment);
230 /* Do we have more scatterlist entries? */
231 debug_tcp("total copied %u total size %u\n", segment->total_copied,
232 segment->total_size);
233 if (segment->total_copied < segment->total_size) {
234 /* Proceed to the next entry in the scatterlist. */
235 iscsi_tcp_segment_init_sg(segment, sg_next(segment->sg),
237 iscsi_tcp_segment_map(segment, recv);
238 BUG_ON(segment->size == 0);
242 /* Do we need to handle padding? */
243 pad = iscsi_padding(segment->total_copied);
245 debug_tcp("consume %d pad bytes\n", pad);
246 segment->total_size += pad;
248 segment->data = padbuf;
253 * Set us up for transferring the data digest. hdr digest
254 * is completely handled in hdr done function.
257 crypto_hash_final(segment->hash, segment->digest);
258 iscsi_tcp_segment_splice_digest(segment,
259 recv ? segment->recv_digest : segment->digest);
267 * iscsi_tcp_xmit_segment - transmit segment
268 * @tcp_conn: the iSCSI TCP connection
269 * @segment: the buffer to transmnit
271 * This function transmits as much of the buffer as
272 * the network layer will accept, and returns the number of
275 * If CRC hashing is enabled, the function will compute the
276 * hash as it goes. When the entire segment has been transmitted,
277 * it will retrieve the hash value and send it as well.
280 iscsi_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
281 struct iscsi_segment *segment)
283 struct socket *sk = tcp_conn->sock;
284 unsigned int copied = 0;
287 while (!iscsi_tcp_segment_done(segment, 0, r)) {
288 struct scatterlist *sg;
289 unsigned int offset, copy;
293 offset = segment->copied;
294 copy = segment->size - offset;
296 if (segment->total_copied + segment->size < segment->total_size)
299 /* Use sendpage if we can; else fall back to sendmsg */
300 if (!segment->data) {
302 offset += segment->sg_offset + sg->offset;
303 r = tcp_conn->sendpage(sk, sg_page(sg), offset, copy,
306 struct msghdr msg = { .msg_flags = flags };
308 .iov_base = segment->data + offset,
312 r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
316 iscsi_tcp_segment_unmap(segment);
317 if (copied || r == -EAGAIN)
327 * iscsi_tcp_segment_recv - copy data to segment
328 * @tcp_conn: the iSCSI TCP connection
329 * @segment: the buffer to copy to
331 * @len: amount of data available
333 * This function copies up to @len bytes to the
334 * given buffer, and returns the number of bytes
335 * consumed, which can actually be less than @len.
337 * If hash digest is enabled, the function will update the
338 * hash while copying.
339 * Combining these two operations doesn't buy us a lot (yet),
340 * but in the future we could implement combined copy+crc,
341 * just way we do for network layer checksums.
344 iscsi_tcp_segment_recv(struct iscsi_tcp_conn *tcp_conn,
345 struct iscsi_segment *segment, const void *ptr,
348 unsigned int copy = 0, copied = 0;
350 while (!iscsi_tcp_segment_done(segment, 1, copy)) {
352 debug_tcp("iscsi_tcp_segment_recv copied %d bytes\n",
357 copy = min(len - copied, segment->size - segment->copied);
358 debug_tcp("iscsi_tcp_segment_recv copying %d\n", copy);
359 memcpy(segment->data + segment->copied, ptr + copied, copy);
366 iscsi_tcp_dgst_header(struct hash_desc *hash, const void *hdr, size_t hdrlen,
367 unsigned char digest[ISCSI_DIGEST_SIZE])
369 struct scatterlist sg;
371 sg_init_one(&sg, hdr, hdrlen);
372 crypto_hash_digest(hash, &sg, hdrlen, digest);
376 iscsi_tcp_dgst_verify(struct iscsi_tcp_conn *tcp_conn,
377 struct iscsi_segment *segment)
379 if (!segment->digest_len)
382 if (memcmp(segment->recv_digest, segment->digest,
383 segment->digest_len)) {
384 debug_scsi("digest mismatch\n");
392 * Helper function to set up segment buffer
395 __iscsi_segment_init(struct iscsi_segment *segment, size_t size,
396 iscsi_segment_done_fn_t *done, struct hash_desc *hash)
398 memset(segment, 0, sizeof(*segment));
399 segment->total_size = size;
400 segment->done = done;
403 segment->hash = hash;
404 crypto_hash_init(hash);
409 iscsi_segment_init_linear(struct iscsi_segment *segment, void *data,
410 size_t size, iscsi_segment_done_fn_t *done,
411 struct hash_desc *hash)
413 __iscsi_segment_init(segment, size, done, hash);
414 segment->data = data;
415 segment->size = size;
419 iscsi_segment_seek_sg(struct iscsi_segment *segment,
420 struct scatterlist *sg_list, unsigned int sg_count,
421 unsigned int offset, size_t size,
422 iscsi_segment_done_fn_t *done, struct hash_desc *hash)
424 struct scatterlist *sg;
427 debug_scsi("iscsi_segment_seek_sg offset %u size %llu\n",
429 __iscsi_segment_init(segment, size, done, hash);
430 for_each_sg(sg_list, sg, sg_count, i) {
431 debug_scsi("sg %d, len %u offset %u\n", i, sg->length,
433 if (offset < sg->length) {
434 iscsi_tcp_segment_init_sg(segment, sg, offset);
437 offset -= sg->length;
440 return ISCSI_ERR_DATA_OFFSET;
444 * iscsi_tcp_hdr_recv_prep - prep segment for hdr reception
445 * @tcp_conn: iscsi connection to prep for
447 * This function always passes NULL for the hash argument, because when this
448 * function is called we do not yet know the final size of the header and want
449 * to delay the digest processing until we know that.
452 iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn)
454 debug_tcp("iscsi_tcp_hdr_recv_prep(%p%s)\n", tcp_conn,
455 tcp_conn->iscsi_conn->hdrdgst_en ? ", digest enabled" : "");
456 iscsi_segment_init_linear(&tcp_conn->in.segment,
457 tcp_conn->in.hdr_buf, sizeof(struct iscsi_hdr),
458 iscsi_tcp_hdr_recv_done, NULL);
462 * Handle incoming reply to any other type of command
465 iscsi_tcp_data_recv_done(struct iscsi_tcp_conn *tcp_conn,
466 struct iscsi_segment *segment)
468 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
471 if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
472 return ISCSI_ERR_DATA_DGST;
474 rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr,
475 conn->data, tcp_conn->in.datalen);
479 iscsi_tcp_hdr_recv_prep(tcp_conn);
484 iscsi_tcp_data_recv_prep(struct iscsi_tcp_conn *tcp_conn)
486 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
487 struct hash_desc *rx_hash = NULL;
489 if (conn->datadgst_en)
490 rx_hash = &tcp_conn->rx_hash;
492 iscsi_segment_init_linear(&tcp_conn->in.segment,
493 conn->data, tcp_conn->in.datalen,
494 iscsi_tcp_data_recv_done, rx_hash);
498 * must be called with session lock
501 iscsi_tcp_cleanup_task(struct iscsi_conn *conn, struct iscsi_task *task)
503 struct iscsi_tcp_task *tcp_task = task->dd_data;
504 struct iscsi_r2t_info *r2t;
506 /* nothing to do for mgmt tasks */
510 /* flush task's r2t queues */
511 while (__kfifo_get(tcp_task->r2tqueue, (void*)&r2t, sizeof(void*))) {
512 __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
514 debug_scsi("iscsi_tcp_cleanup_task pending r2t dropped\n");
519 __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
521 tcp_task->r2t = NULL;
526 * iscsi_data_rsp - SCSI Data-In Response processing
527 * @conn: iscsi connection
528 * @task: scsi command task
531 iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_task *task)
533 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
534 struct iscsi_tcp_task *tcp_task = task->dd_data;
535 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)tcp_conn->in.hdr;
536 struct iscsi_session *session = conn->session;
537 struct scsi_cmnd *sc = task->sc;
538 int datasn = be32_to_cpu(rhdr->datasn);
539 unsigned total_in_length = scsi_in(sc)->length;
541 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
542 if (tcp_conn->in.datalen == 0)
545 if (tcp_task->exp_datasn != datasn) {
546 debug_tcp("%s: task->exp_datasn(%d) != rhdr->datasn(%d)\n",
547 __func__, tcp_task->exp_datasn, datasn);
548 return ISCSI_ERR_DATASN;
551 tcp_task->exp_datasn++;
553 tcp_task->data_offset = be32_to_cpu(rhdr->offset);
554 if (tcp_task->data_offset + tcp_conn->in.datalen > total_in_length) {
555 debug_tcp("%s: data_offset(%d) + data_len(%d) > total_length_in(%d)\n",
556 __func__, tcp_task->data_offset,
557 tcp_conn->in.datalen, total_in_length);
558 return ISCSI_ERR_DATA_OFFSET;
561 if (rhdr->flags & ISCSI_FLAG_DATA_STATUS) {
562 sc->result = (DID_OK << 16) | rhdr->cmd_status;
563 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
564 if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
565 ISCSI_FLAG_DATA_OVERFLOW)) {
566 int res_count = be32_to_cpu(rhdr->residual_count);
569 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
570 res_count <= total_in_length))
571 scsi_in(sc)->resid = res_count;
573 sc->result = (DID_BAD_TARGET << 16) |
578 conn->datain_pdus_cnt++;
583 * iscsi_solicit_data_init - initialize first Data-Out
584 * @conn: iscsi connection
585 * @task: scsi command task
589 * Initialize first Data-Out within this R2T sequence and finds
590 * proper data_offset within this SCSI command.
592 * This function is called with connection lock taken.
595 iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_task *task,
596 struct iscsi_r2t_info *r2t)
598 struct iscsi_data *hdr;
600 hdr = &r2t->dtask.hdr;
601 memset(hdr, 0, sizeof(struct iscsi_data));
603 hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
604 r2t->solicit_datasn++;
605 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
606 memcpy(hdr->lun, task->hdr->lun, sizeof(hdr->lun));
607 hdr->itt = task->hdr->itt;
608 hdr->exp_statsn = r2t->exp_statsn;
609 hdr->offset = cpu_to_be32(r2t->data_offset);
610 if (r2t->data_length > conn->max_xmit_dlength) {
611 hton24(hdr->dlength, conn->max_xmit_dlength);
612 r2t->data_count = conn->max_xmit_dlength;
615 hton24(hdr->dlength, r2t->data_length);
616 r2t->data_count = r2t->data_length;
617 hdr->flags = ISCSI_FLAG_CMD_FINAL;
619 conn->dataout_pdus_cnt++;
625 * iscsi_r2t_rsp - iSCSI R2T Response processing
626 * @conn: iscsi connection
627 * @task: scsi command task
630 iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_task *task)
632 struct iscsi_r2t_info *r2t;
633 struct iscsi_session *session = conn->session;
634 struct iscsi_tcp_task *tcp_task = task->dd_data;
635 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
636 struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr;
637 int r2tsn = be32_to_cpu(rhdr->r2tsn);
640 if (tcp_conn->in.datalen) {
641 iscsi_conn_printk(KERN_ERR, conn,
642 "invalid R2t with datalen %d\n",
643 tcp_conn->in.datalen);
644 return ISCSI_ERR_DATALEN;
647 if (tcp_task->exp_datasn != r2tsn){
648 debug_tcp("%s: task->exp_datasn(%d) != rhdr->r2tsn(%d)\n",
649 __func__, tcp_task->exp_datasn, r2tsn);
650 return ISCSI_ERR_R2TSN;
653 /* fill-in new R2T associated with the task */
654 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
656 if (!task->sc || session->state != ISCSI_STATE_LOGGED_IN) {
657 iscsi_conn_printk(KERN_INFO, conn,
658 "dropping R2T itt %d in recovery.\n",
663 rc = __kfifo_get(tcp_task->r2tpool.queue, (void*)&r2t, sizeof(void*));
666 r2t->exp_statsn = rhdr->statsn;
667 r2t->data_length = be32_to_cpu(rhdr->data_length);
668 if (r2t->data_length == 0) {
669 iscsi_conn_printk(KERN_ERR, conn,
670 "invalid R2T with zero data len\n");
671 __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
673 return ISCSI_ERR_DATALEN;
676 if (r2t->data_length > session->max_burst)
677 debug_scsi("invalid R2T with data len %u and max burst %u."
678 "Attempting to execute request.\n",
679 r2t->data_length, session->max_burst);
681 r2t->data_offset = be32_to_cpu(rhdr->data_offset);
682 if (r2t->data_offset + r2t->data_length > scsi_out(task->sc)->length) {
683 iscsi_conn_printk(KERN_ERR, conn,
684 "invalid R2T with data len %u at offset %u "
685 "and total length %d\n", r2t->data_length,
686 r2t->data_offset, scsi_out(task->sc)->length);
687 __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
689 return ISCSI_ERR_DATALEN;
692 r2t->ttt = rhdr->ttt; /* no flip */
693 r2t->solicit_datasn = 0;
695 iscsi_solicit_data_init(conn, task, r2t);
697 tcp_task->exp_datasn = r2tsn + 1;
698 __kfifo_put(tcp_task->r2tqueue, (void*)&r2t, sizeof(void*));
699 conn->r2t_pdus_cnt++;
701 iscsi_requeue_task(task);
706 * Handle incoming reply to DataIn command
709 iscsi_tcp_process_data_in(struct iscsi_tcp_conn *tcp_conn,
710 struct iscsi_segment *segment)
712 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
713 struct iscsi_hdr *hdr = tcp_conn->in.hdr;
716 if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
717 return ISCSI_ERR_DATA_DGST;
719 /* check for non-exceptional status */
720 if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
721 rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
726 iscsi_tcp_hdr_recv_prep(tcp_conn);
731 * iscsi_tcp_hdr_dissect - process PDU header
732 * @conn: iSCSI connection
735 * This function analyzes the header of the PDU received,
736 * and performs several sanity checks. If the PDU is accompanied
737 * by data, the receive buffer is set up to copy the incoming data
738 * to the correct location.
741 iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
743 int rc = 0, opcode, ahslen;
744 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
745 struct iscsi_task *task;
747 /* verify PDU length */
748 tcp_conn->in.datalen = ntoh24(hdr->dlength);
749 if (tcp_conn->in.datalen > conn->max_recv_dlength) {
750 iscsi_conn_printk(KERN_ERR, conn,
751 "iscsi_tcp: datalen %d > %d\n",
752 tcp_conn->in.datalen, conn->max_recv_dlength);
753 return ISCSI_ERR_DATALEN;
756 /* Additional header segments. So far, we don't
757 * process additional headers.
759 ahslen = hdr->hlength << 2;
761 opcode = hdr->opcode & ISCSI_OPCODE_MASK;
762 /* verify itt (itt encoding: age+cid+itt) */
763 rc = iscsi_verify_itt(conn, hdr->itt);
767 debug_tcp("opcode 0x%x ahslen %d datalen %d\n",
768 opcode, ahslen, tcp_conn->in.datalen);
771 case ISCSI_OP_SCSI_DATA_IN:
772 spin_lock(&conn->session->lock);
773 task = iscsi_itt_to_ctask(conn, hdr->itt);
775 rc = ISCSI_ERR_BAD_ITT;
777 rc = iscsi_data_rsp(conn, task);
779 spin_unlock(&conn->session->lock);
783 if (tcp_conn->in.datalen) {
784 struct iscsi_tcp_task *tcp_task = task->dd_data;
785 struct hash_desc *rx_hash = NULL;
786 struct scsi_data_buffer *sdb = scsi_in(task->sc);
789 * Setup copy of Data-In into the Scsi_Cmnd
791 * We set up the iscsi_segment to point to the next
792 * scatterlist entry to copy to. As we go along,
793 * we move on to the next scatterlist entry and
794 * update the digest per-entry.
796 if (conn->datadgst_en)
797 rx_hash = &tcp_conn->rx_hash;
799 debug_tcp("iscsi_tcp_begin_data_in(%p, offset=%d, "
800 "datalen=%d)\n", tcp_conn,
801 tcp_task->data_offset,
802 tcp_conn->in.datalen);
803 rc = iscsi_segment_seek_sg(&tcp_conn->in.segment,
806 tcp_task->data_offset,
807 tcp_conn->in.datalen,
808 iscsi_tcp_process_data_in,
810 spin_unlock(&conn->session->lock);
813 rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
814 spin_unlock(&conn->session->lock);
816 case ISCSI_OP_SCSI_CMD_RSP:
817 if (tcp_conn->in.datalen) {
818 iscsi_tcp_data_recv_prep(tcp_conn);
821 rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
824 spin_lock(&conn->session->lock);
825 task = iscsi_itt_to_ctask(conn, hdr->itt);
827 rc = ISCSI_ERR_BAD_ITT;
829 rc = ISCSI_ERR_AHSLEN;
830 else if (task->sc->sc_data_direction == DMA_TO_DEVICE)
831 rc = iscsi_r2t_rsp(conn, task);
833 rc = ISCSI_ERR_PROTO;
834 spin_unlock(&conn->session->lock);
836 case ISCSI_OP_LOGIN_RSP:
837 case ISCSI_OP_TEXT_RSP:
838 case ISCSI_OP_REJECT:
839 case ISCSI_OP_ASYNC_EVENT:
841 * It is possible that we could get a PDU with a buffer larger
842 * than 8K, but there are no targets that currently do this.
843 * For now we fail until we find a vendor that needs it
845 if (ISCSI_DEF_MAX_RECV_SEG_LEN < tcp_conn->in.datalen) {
846 iscsi_conn_printk(KERN_ERR, conn,
847 "iscsi_tcp: received buffer of "
848 "len %u but conn buffer is only %u "
850 tcp_conn->in.datalen,
851 ISCSI_DEF_MAX_RECV_SEG_LEN, opcode);
852 rc = ISCSI_ERR_PROTO;
856 /* If there's data coming in with the response,
857 * receive it to the connection's buffer.
859 if (tcp_conn->in.datalen) {
860 iscsi_tcp_data_recv_prep(tcp_conn);
864 case ISCSI_OP_LOGOUT_RSP:
865 case ISCSI_OP_NOOP_IN:
866 case ISCSI_OP_SCSI_TMFUNC_RSP:
867 rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
870 rc = ISCSI_ERR_BAD_OPCODE;
875 /* Anything that comes with data should have
876 * been handled above. */
877 if (tcp_conn->in.datalen)
878 return ISCSI_ERR_PROTO;
879 iscsi_tcp_hdr_recv_prep(tcp_conn);
886 * iscsi_tcp_hdr_recv_done - process PDU header
888 * This is the callback invoked when the PDU header has
889 * been received. If the header is followed by additional
890 * header segments, we go back for more data.
893 iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
894 struct iscsi_segment *segment)
896 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
897 struct iscsi_hdr *hdr;
899 /* Check if there are additional header segments
900 * *prior* to computing the digest, because we
901 * may need to go back to the caller for more.
903 hdr = (struct iscsi_hdr *) tcp_conn->in.hdr_buf;
904 if (segment->copied == sizeof(struct iscsi_hdr) && hdr->hlength) {
905 /* Bump the header length - the caller will
906 * just loop around and get the AHS for us, and
908 unsigned int ahslen = hdr->hlength << 2;
910 /* Make sure we don't overflow */
911 if (sizeof(*hdr) + ahslen > sizeof(tcp_conn->in.hdr_buf))
912 return ISCSI_ERR_AHSLEN;
914 segment->total_size += ahslen;
915 segment->size += ahslen;
919 /* We're done processing the header. See if we're doing
920 * header digests; if so, set up the recv_digest buffer
921 * and go back for more. */
922 if (conn->hdrdgst_en) {
923 if (segment->digest_len == 0) {
924 iscsi_tcp_segment_splice_digest(segment,
925 segment->recv_digest);
928 iscsi_tcp_dgst_header(&tcp_conn->rx_hash, hdr,
929 segment->total_copied - ISCSI_DIGEST_SIZE,
932 if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
933 return ISCSI_ERR_HDR_DGST;
936 tcp_conn->in.hdr = hdr;
937 return iscsi_tcp_hdr_dissect(conn, hdr);
941 * iscsi_tcp_recv - TCP receive in sendfile fashion
942 * @rd_desc: read descriptor
943 * @skb: socket buffer
944 * @offset: offset in skb
945 * @len: skb->len - offset
948 iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
949 unsigned int offset, size_t len)
951 struct iscsi_conn *conn = rd_desc->arg.data;
952 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
953 struct iscsi_segment *segment = &tcp_conn->in.segment;
954 struct skb_seq_state seq;
955 unsigned int consumed = 0;
958 debug_tcp("in %d bytes\n", skb->len - offset);
960 if (unlikely(conn->suspend_rx)) {
961 debug_tcp("conn %d Rx suspended!\n", conn->id);
965 skb_prepare_seq_read(skb, offset, skb->len, &seq);
970 avail = skb_seq_read(consumed, &ptr, &seq);
972 debug_tcp("no more data avail. Consumed %d\n",
976 BUG_ON(segment->copied >= segment->size);
978 debug_tcp("skb %p ptr=%p avail=%u\n", skb, ptr, avail);
979 rc = iscsi_tcp_segment_recv(tcp_conn, segment, ptr, avail);
983 if (segment->total_copied >= segment->total_size) {
984 debug_tcp("segment done\n");
985 rc = segment->done(tcp_conn, segment);
987 skb_abort_seq_read(&seq);
991 /* The done() functions sets up the
995 skb_abort_seq_read(&seq);
996 conn->rxdata_octets += consumed;
1000 debug_tcp("Error receiving PDU, errno=%d\n", rc);
1001 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1006 iscsi_tcp_data_ready(struct sock *sk, int flag)
1008 struct iscsi_conn *conn = sk->sk_user_data;
1009 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1010 read_descriptor_t rd_desc;
1012 read_lock(&sk->sk_callback_lock);
1015 * Use rd_desc to pass 'conn' to iscsi_tcp_recv.
1016 * We set count to 1 because we want the network layer to
1017 * hand us all the skbs that are available. iscsi_tcp_recv
1018 * handled pdus that cross buffers or pdus that still need data.
1020 rd_desc.arg.data = conn;
1022 tcp_read_sock(sk, &rd_desc, iscsi_tcp_recv);
1024 read_unlock(&sk->sk_callback_lock);
1026 /* If we had to (atomically) map a highmem page,
1028 iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
1032 iscsi_tcp_state_change(struct sock *sk)
1034 struct iscsi_tcp_conn *tcp_conn;
1035 struct iscsi_conn *conn;
1036 struct iscsi_session *session;
1037 void (*old_state_change)(struct sock *);
1039 read_lock(&sk->sk_callback_lock);
1041 conn = (struct iscsi_conn*)sk->sk_user_data;
1042 session = conn->session;
1044 if ((sk->sk_state == TCP_CLOSE_WAIT ||
1045 sk->sk_state == TCP_CLOSE) &&
1046 !atomic_read(&sk->sk_rmem_alloc)) {
1047 debug_tcp("iscsi_tcp_state_change: TCP_CLOSE|TCP_CLOSE_WAIT\n");
1048 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1051 tcp_conn = conn->dd_data;
1052 old_state_change = tcp_conn->old_state_change;
1054 read_unlock(&sk->sk_callback_lock);
1056 old_state_change(sk);
1060 * iscsi_write_space - Called when more output buffer space is available
1061 * @sk: socket space is available for
1064 iscsi_write_space(struct sock *sk)
1066 struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
1067 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1069 tcp_conn->old_write_space(sk);
1070 debug_tcp("iscsi_write_space: cid %d\n", conn->id);
1071 scsi_queue_work(conn->session->host, &conn->xmitwork);
1075 iscsi_conn_set_callbacks(struct iscsi_conn *conn)
1077 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1078 struct sock *sk = tcp_conn->sock->sk;
1080 /* assign new callbacks */
1081 write_lock_bh(&sk->sk_callback_lock);
1082 sk->sk_user_data = conn;
1083 tcp_conn->old_data_ready = sk->sk_data_ready;
1084 tcp_conn->old_state_change = sk->sk_state_change;
1085 tcp_conn->old_write_space = sk->sk_write_space;
1086 sk->sk_data_ready = iscsi_tcp_data_ready;
1087 sk->sk_state_change = iscsi_tcp_state_change;
1088 sk->sk_write_space = iscsi_write_space;
1089 write_unlock_bh(&sk->sk_callback_lock);
1093 iscsi_conn_restore_callbacks(struct iscsi_tcp_conn *tcp_conn)
1095 struct sock *sk = tcp_conn->sock->sk;
1097 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
1098 write_lock_bh(&sk->sk_callback_lock);
1099 sk->sk_user_data = NULL;
1100 sk->sk_data_ready = tcp_conn->old_data_ready;
1101 sk->sk_state_change = tcp_conn->old_state_change;
1102 sk->sk_write_space = tcp_conn->old_write_space;
1103 sk->sk_no_check = 0;
1104 write_unlock_bh(&sk->sk_callback_lock);
1108 * iscsi_xmit - TCP transmit
1111 iscsi_xmit(struct iscsi_conn *conn)
1113 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1114 struct iscsi_segment *segment = &tcp_conn->out.segment;
1115 unsigned int consumed = 0;
1119 rc = iscsi_tcp_xmit_segment(tcp_conn, segment);
1127 if (segment->total_copied >= segment->total_size) {
1128 if (segment->done != NULL) {
1129 rc = segment->done(tcp_conn, segment);
1136 debug_tcp("xmit %d bytes\n", consumed);
1138 conn->txdata_octets += consumed;
1142 /* Transmit error. We could initiate error recovery
1144 debug_tcp("Error sending PDU, errno=%d\n", rc);
1145 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1150 * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit
1153 iscsi_tcp_xmit_qlen(struct iscsi_conn *conn)
1155 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1156 struct iscsi_segment *segment = &tcp_conn->out.segment;
1158 return segment->total_copied - segment->total_size;
1162 iscsi_tcp_flush(struct iscsi_conn *conn)
1166 while (iscsi_tcp_xmit_qlen(conn)) {
1167 rc = iscsi_xmit(conn);
1178 * This is called when we're done sending the header.
1179 * Simply copy the data_segment to the send segment, and return.
1182 iscsi_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
1183 struct iscsi_segment *segment)
1185 tcp_conn->out.segment = tcp_conn->out.data_segment;
1186 debug_tcp("Header done. Next segment size %u total_size %u\n",
1187 tcp_conn->out.segment.size, tcp_conn->out.segment.total_size);
1192 iscsi_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, size_t hdrlen)
1194 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1196 debug_tcp("%s(%p%s)\n", __func__, tcp_conn,
1197 conn->hdrdgst_en? ", digest enabled" : "");
1199 /* Clear the data segment - needs to be filled in by the
1200 * caller using iscsi_tcp_send_data_prep() */
1201 memset(&tcp_conn->out.data_segment, 0, sizeof(struct iscsi_segment));
1203 /* If header digest is enabled, compute the CRC and
1204 * place the digest into the same buffer. We make
1205 * sure that both iscsi_tcp_task and mtask have
1208 if (conn->hdrdgst_en) {
1209 iscsi_tcp_dgst_header(&tcp_conn->tx_hash, hdr, hdrlen,
1211 hdrlen += ISCSI_DIGEST_SIZE;
1214 /* Remember header pointer for later, when we need
1215 * to decide whether there's a payload to go along
1216 * with the header. */
1217 tcp_conn->out.hdr = hdr;
1219 iscsi_segment_init_linear(&tcp_conn->out.segment, hdr, hdrlen,
1220 iscsi_tcp_send_hdr_done, NULL);
1224 * Prepare the send buffer for the payload data.
1225 * Padding and checksumming will all be taken care
1226 * of by the iscsi_segment routines.
1229 iscsi_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
1230 unsigned int count, unsigned int offset,
1233 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1234 struct hash_desc *tx_hash = NULL;
1235 unsigned int hdr_spec_len;
1237 debug_tcp("%s(%p, offset=%d, datalen=%d%s)\n", __func__,
1238 tcp_conn, offset, len,
1239 conn->datadgst_en? ", digest enabled" : "");
1241 /* Make sure the datalen matches what the caller
1242 said he would send. */
1243 hdr_spec_len = ntoh24(tcp_conn->out.hdr->dlength);
1244 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
1246 if (conn->datadgst_en)
1247 tx_hash = &tcp_conn->tx_hash;
1249 return iscsi_segment_seek_sg(&tcp_conn->out.data_segment,
1250 sg, count, offset, len,
1255 iscsi_tcp_send_linear_data_prepare(struct iscsi_conn *conn, void *data,
1258 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1259 struct hash_desc *tx_hash = NULL;
1260 unsigned int hdr_spec_len;
1262 debug_tcp("%s(%p, datalen=%d%s)\n", __func__, tcp_conn, len,
1263 conn->datadgst_en? ", digest enabled" : "");
1265 /* Make sure the datalen matches what the caller
1266 said he would send. */
1267 hdr_spec_len = ntoh24(tcp_conn->out.hdr->dlength);
1268 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
1270 if (conn->datadgst_en)
1271 tx_hash = &tcp_conn->tx_hash;
1273 iscsi_segment_init_linear(&tcp_conn->out.data_segment,
1274 data, len, NULL, tx_hash);
1278 * iscsi_solicit_data_cont - initialize next Data-Out
1279 * @conn: iscsi connection
1280 * @task: scsi command task
1282 * @left: bytes left to transfer
1285 * Initialize next Data-Out within this R2T sequence and continue
1286 * to process next Scatter-Gather element(if any) of this SCSI command.
1288 * Called under connection lock.
1291 iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_task *task,
1292 struct iscsi_r2t_info *r2t)
1294 struct iscsi_data *hdr;
1295 int new_offset, left;
1297 BUG_ON(r2t->data_length - r2t->sent < 0);
1298 left = r2t->data_length - r2t->sent;
1302 hdr = &r2t->dtask.hdr;
1303 memset(hdr, 0, sizeof(struct iscsi_data));
1304 hdr->ttt = r2t->ttt;
1305 hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
1306 r2t->solicit_datasn++;
1307 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
1308 memcpy(hdr->lun, task->hdr->lun, sizeof(hdr->lun));
1309 hdr->itt = task->hdr->itt;
1310 hdr->exp_statsn = r2t->exp_statsn;
1311 new_offset = r2t->data_offset + r2t->sent;
1312 hdr->offset = cpu_to_be32(new_offset);
1313 if (left > conn->max_xmit_dlength) {
1314 hton24(hdr->dlength, conn->max_xmit_dlength);
1315 r2t->data_count = conn->max_xmit_dlength;
1317 hton24(hdr->dlength, left);
1318 r2t->data_count = left;
1319 hdr->flags = ISCSI_FLAG_CMD_FINAL;
1322 conn->dataout_pdus_cnt++;
1327 * iscsi_tcp_task - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
1328 * @conn: iscsi connection
1329 * @task: scsi command task
1333 iscsi_tcp_task_init(struct iscsi_task *task)
1335 struct iscsi_tcp_task *tcp_task = task->dd_data;
1336 struct iscsi_conn *conn = task->conn;
1337 struct scsi_cmnd *sc = task->sc;
1342 * mgmt tasks do not have a scatterlist since they come
1343 * in from the iscsi interface.
1345 debug_scsi("mtask deq [cid %d itt 0x%x]\n", conn->id,
1348 /* Prepare PDU, optionally w/ immediate data */
1349 iscsi_tcp_send_hdr_prep(conn, task->hdr, sizeof(*task->hdr));
1351 /* If we have immediate data, attach a payload */
1352 if (task->data_count)
1353 iscsi_tcp_send_linear_data_prepare(conn, task->data,
1358 BUG_ON(__kfifo_len(tcp_task->r2tqueue));
1360 tcp_task->exp_datasn = 0;
1362 /* Prepare PDU, optionally w/ immediate data */
1363 debug_scsi("task deq [cid %d itt 0x%x imm %d unsol %d]\n",
1364 conn->id, task->itt, task->imm_count,
1366 iscsi_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
1368 if (!task->imm_count)
1371 /* If we have immediate data, attach a payload */
1372 err = iscsi_tcp_send_data_prep(conn, scsi_out(sc)->table.sgl,
1373 scsi_out(sc)->table.nents,
1374 0, task->imm_count);
1377 tcp_task->sent += task->imm_count;
1378 task->imm_count = 0;
1383 * iscsi_tcp_task_xmit - xmit normal PDU task
1384 * @task: iscsi command task
1386 * We're expected to return 0 when everything was transmitted succesfully,
1387 * -EAGAIN if there's still data in the queue, or != 0 for any other kind
1391 iscsi_tcp_task_xmit(struct iscsi_task *task)
1393 struct iscsi_conn *conn = task->conn;
1394 struct iscsi_tcp_task *tcp_task = task->dd_data;
1395 struct scsi_cmnd *sc = task->sc;
1396 struct scsi_data_buffer *sdb;
1400 /* Flush any pending data first. */
1401 rc = iscsi_tcp_flush(conn);
1407 if (task->hdr->itt == RESERVED_ITT)
1408 iscsi_put_task(task);
1412 /* Are we done already? */
1413 if (sc->sc_data_direction != DMA_TO_DEVICE)
1417 if (task->unsol_count != 0) {
1418 struct iscsi_data *hdr = &tcp_task->unsol_dtask.hdr;
1420 /* Prepare a header for the unsolicited PDU.
1421 * The amount of data we want to send will be
1422 * in task->data_count.
1423 * FIXME: return the data count instead.
1425 iscsi_prep_unsolicit_data_pdu(task, hdr);
1427 debug_tcp("unsol dout [itt 0x%x doff %d dlen %d]\n",
1428 task->itt, tcp_task->sent, task->data_count);
1430 iscsi_tcp_send_hdr_prep(conn, hdr, sizeof(*hdr));
1431 rc = iscsi_tcp_send_data_prep(conn, sdb->table.sgl,
1432 sdb->table.nents, tcp_task->sent,
1436 tcp_task->sent += task->data_count;
1437 task->unsol_count -= task->data_count;
1440 struct iscsi_session *session = conn->session;
1441 struct iscsi_r2t_info *r2t;
1443 /* All unsolicited PDUs sent. Check for solicited PDUs.
1445 spin_lock_bh(&session->lock);
1446 r2t = tcp_task->r2t;
1448 /* Continue with this R2T? */
1449 if (!iscsi_solicit_data_cont(conn, task, r2t)) {
1450 debug_scsi(" done with r2t %p\n", r2t);
1452 __kfifo_put(tcp_task->r2tpool.queue,
1453 (void*)&r2t, sizeof(void*));
1454 tcp_task->r2t = r2t = NULL;
1459 __kfifo_get(tcp_task->r2tqueue, (void*)&tcp_task->r2t,
1461 r2t = tcp_task->r2t;
1463 spin_unlock_bh(&session->lock);
1465 /* Waiting for more R2Ts to arrive. */
1467 debug_tcp("no R2Ts yet\n");
1471 debug_scsi("sol dout %p [dsn %d itt 0x%x doff %d dlen %d]\n",
1472 r2t, r2t->solicit_datasn - 1, task->itt,
1473 r2t->data_offset + r2t->sent, r2t->data_count);
1475 iscsi_tcp_send_hdr_prep(conn, &r2t->dtask.hdr,
1476 sizeof(struct iscsi_hdr));
1478 rc = iscsi_tcp_send_data_prep(conn, sdb->table.sgl,
1480 r2t->data_offset + r2t->sent,
1484 tcp_task->sent += r2t->data_count;
1485 r2t->sent += r2t->data_count;
1490 iscsi_conn_failure(conn, rc);
1494 static struct iscsi_cls_conn *
1495 iscsi_tcp_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1497 struct iscsi_conn *conn;
1498 struct iscsi_cls_conn *cls_conn;
1499 struct iscsi_tcp_conn *tcp_conn;
1501 cls_conn = iscsi_conn_setup(cls_session, sizeof(*tcp_conn), conn_idx);
1504 conn = cls_conn->dd_data;
1506 * due to strange issues with iser these are not set
1507 * in iscsi_conn_setup
1509 conn->max_recv_dlength = ISCSI_DEF_MAX_RECV_SEG_LEN;
1511 tcp_conn = conn->dd_data;
1512 tcp_conn->iscsi_conn = conn;
1514 tcp_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0,
1516 tcp_conn->tx_hash.flags = 0;
1517 if (IS_ERR(tcp_conn->tx_hash.tfm))
1520 tcp_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0,
1522 tcp_conn->rx_hash.flags = 0;
1523 if (IS_ERR(tcp_conn->rx_hash.tfm))
1529 crypto_free_hash(tcp_conn->tx_hash.tfm);
1531 iscsi_conn_printk(KERN_ERR, conn,
1532 "Could not create connection due to crc32c "
1533 "loading error. Make sure the crc32c "
1534 "module is built as a module or into the "
1536 iscsi_conn_teardown(cls_conn);
1541 iscsi_tcp_release_conn(struct iscsi_conn *conn)
1543 struct iscsi_session *session = conn->session;
1544 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1545 struct socket *sock = tcp_conn->sock;
1550 sock_hold(sock->sk);
1551 iscsi_conn_restore_callbacks(tcp_conn);
1554 spin_lock_bh(&session->lock);
1555 tcp_conn->sock = NULL;
1556 spin_unlock_bh(&session->lock);
1561 iscsi_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
1563 struct iscsi_conn *conn = cls_conn->dd_data;
1564 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1566 iscsi_tcp_release_conn(conn);
1568 if (tcp_conn->tx_hash.tfm)
1569 crypto_free_hash(tcp_conn->tx_hash.tfm);
1570 if (tcp_conn->rx_hash.tfm)
1571 crypto_free_hash(tcp_conn->rx_hash.tfm);
1573 iscsi_conn_teardown(cls_conn);
1577 iscsi_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1579 struct iscsi_conn *conn = cls_conn->dd_data;
1580 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1582 /* userspace may have goofed up and not bound us */
1583 if (!tcp_conn->sock)
1586 * Make sure our recv side is stopped.
1587 * Older tools called conn stop before ep_disconnect
1588 * so IO could still be coming in.
1590 write_lock_bh(&tcp_conn->sock->sk->sk_callback_lock);
1591 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1592 write_unlock_bh(&tcp_conn->sock->sk->sk_callback_lock);
1594 iscsi_conn_stop(cls_conn, flag);
1595 iscsi_tcp_release_conn(conn);
1598 static int iscsi_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock,
1599 char *buf, int *port,
1600 int (*getname)(struct socket *, struct sockaddr *,
1603 struct sockaddr_storage *addr;
1604 struct sockaddr_in6 *sin6;
1605 struct sockaddr_in *sin;
1608 addr = kmalloc(sizeof(*addr), GFP_KERNEL);
1612 if (getname(sock, (struct sockaddr *) addr, &len)) {
1617 switch (addr->ss_family) {
1619 sin = (struct sockaddr_in *)addr;
1620 spin_lock_bh(&conn->session->lock);
1621 sprintf(buf, NIPQUAD_FMT, NIPQUAD(sin->sin_addr.s_addr));
1622 *port = be16_to_cpu(sin->sin_port);
1623 spin_unlock_bh(&conn->session->lock);
1626 sin6 = (struct sockaddr_in6 *)addr;
1627 spin_lock_bh(&conn->session->lock);
1628 sprintf(buf, NIP6_FMT, NIP6(sin6->sin6_addr));
1629 *port = be16_to_cpu(sin6->sin6_port);
1630 spin_unlock_bh(&conn->session->lock);
1639 iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
1640 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
1643 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1644 struct iscsi_host *ihost = shost_priv(shost);
1645 struct iscsi_conn *conn = cls_conn->dd_data;
1646 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1648 struct socket *sock;
1651 /* lookup for existing socket */
1652 sock = sockfd_lookup((int)transport_eph, &err);
1654 iscsi_conn_printk(KERN_ERR, conn,
1655 "sockfd_lookup failed %d\n", err);
1659 * copy these values now because if we drop the session
1660 * userspace may still want to query the values since we will
1661 * be using them for the reconnect
1663 err = iscsi_tcp_get_addr(conn, sock, conn->portal_address,
1664 &conn->portal_port, kernel_getpeername);
1668 err = iscsi_tcp_get_addr(conn, sock, ihost->local_address,
1669 &ihost->local_port, kernel_getsockname);
1673 err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
1677 /* bind iSCSI connection and socket */
1678 tcp_conn->sock = sock;
1680 /* setup Socket parameters */
1683 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
1684 sk->sk_allocation = GFP_ATOMIC;
1686 iscsi_conn_set_callbacks(conn);
1687 tcp_conn->sendpage = tcp_conn->sock->ops->sendpage;
1689 * set receive state machine into initial state
1691 iscsi_tcp_hdr_recv_prep(tcp_conn);
1700 iscsi_r2tpool_alloc(struct iscsi_session *session)
1706 * initialize per-task: R2T pool and xmit queue
1708 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1709 struct iscsi_task *task = session->cmds[cmd_i];
1710 struct iscsi_tcp_task *tcp_task = task->dd_data;
1713 * pre-allocated x4 as much r2ts to handle race when
1714 * target acks DataOut faster than we data_xmit() queues
1715 * could replenish r2tqueue.
1719 if (iscsi_pool_init(&tcp_task->r2tpool, session->max_r2t * 4, NULL,
1720 sizeof(struct iscsi_r2t_info))) {
1721 goto r2t_alloc_fail;
1724 /* R2T xmit queue */
1725 tcp_task->r2tqueue = kfifo_alloc(
1726 session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
1727 if (tcp_task->r2tqueue == ERR_PTR(-ENOMEM)) {
1728 iscsi_pool_free(&tcp_task->r2tpool);
1729 goto r2t_alloc_fail;
1736 for (i = 0; i < cmd_i; i++) {
1737 struct iscsi_task *task = session->cmds[i];
1738 struct iscsi_tcp_task *tcp_task = task->dd_data;
1740 kfifo_free(tcp_task->r2tqueue);
1741 iscsi_pool_free(&tcp_task->r2tpool);
1747 iscsi_r2tpool_free(struct iscsi_session *session)
1751 for (i = 0; i < session->cmds_max; i++) {
1752 struct iscsi_task *task = session->cmds[i];
1753 struct iscsi_tcp_task *tcp_task = task->dd_data;
1755 kfifo_free(tcp_task->r2tqueue);
1756 iscsi_pool_free(&tcp_task->r2tpool);
1761 iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
1762 char *buf, int buflen)
1764 struct iscsi_conn *conn = cls_conn->dd_data;
1765 struct iscsi_session *session = conn->session;
1766 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1770 case ISCSI_PARAM_HDRDGST_EN:
1771 iscsi_set_param(cls_conn, param, buf, buflen);
1773 case ISCSI_PARAM_DATADGST_EN:
1774 iscsi_set_param(cls_conn, param, buf, buflen);
1775 tcp_conn->sendpage = conn->datadgst_en ?
1776 sock_no_sendpage : tcp_conn->sock->ops->sendpage;
1778 case ISCSI_PARAM_MAX_R2T:
1779 sscanf(buf, "%d", &value);
1780 if (value <= 0 || !is_power_of_2(value))
1782 if (session->max_r2t == value)
1784 iscsi_r2tpool_free(session);
1785 iscsi_set_param(cls_conn, param, buf, buflen);
1786 if (iscsi_r2tpool_alloc(session))
1790 return iscsi_set_param(cls_conn, param, buf, buflen);
1797 iscsi_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
1798 enum iscsi_param param, char *buf)
1800 struct iscsi_conn *conn = cls_conn->dd_data;
1804 case ISCSI_PARAM_CONN_PORT:
1805 spin_lock_bh(&conn->session->lock);
1806 len = sprintf(buf, "%hu\n", conn->portal_port);
1807 spin_unlock_bh(&conn->session->lock);
1809 case ISCSI_PARAM_CONN_ADDRESS:
1810 spin_lock_bh(&conn->session->lock);
1811 len = sprintf(buf, "%s\n", conn->portal_address);
1812 spin_unlock_bh(&conn->session->lock);
1815 return iscsi_conn_get_param(cls_conn, param, buf);
1822 iscsi_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
1824 struct iscsi_conn *conn = cls_conn->dd_data;
1825 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1827 stats->txdata_octets = conn->txdata_octets;
1828 stats->rxdata_octets = conn->rxdata_octets;
1829 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
1830 stats->dataout_pdus = conn->dataout_pdus_cnt;
1831 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
1832 stats->datain_pdus = conn->datain_pdus_cnt;
1833 stats->r2t_pdus = conn->r2t_pdus_cnt;
1834 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
1835 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
1836 stats->custom_length = 3;
1837 strcpy(stats->custom[0].desc, "tx_sendpage_failures");
1838 stats->custom[0].value = tcp_conn->sendpage_failures_cnt;
1839 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
1840 stats->custom[1].value = tcp_conn->discontiguous_hdr_cnt;
1841 strcpy(stats->custom[2].desc, "eh_abort_cnt");
1842 stats->custom[2].value = conn->eh_abort_cnt;
1845 static struct iscsi_cls_session *
1846 iscsi_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
1847 uint16_t qdepth, uint32_t initial_cmdsn,
1850 struct iscsi_cls_session *cls_session;
1851 struct iscsi_session *session;
1852 struct Scsi_Host *shost;
1856 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep);
1860 shost = iscsi_host_alloc(&iscsi_sht, 0, qdepth);
1863 shost->transportt = iscsi_tcp_scsi_transport;
1864 shost->max_lun = iscsi_max_lun;
1866 shost->max_channel = 0;
1867 shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
1869 if (iscsi_host_add(shost, NULL))
1871 *hostno = shost->host_no;
1873 cls_session = iscsi_session_setup(&iscsi_tcp_transport, shost, cmds_max,
1874 sizeof(struct iscsi_tcp_task),
1878 session = cls_session->dd_data;
1880 shost->can_queue = session->scsi_cmds_max;
1881 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1882 struct iscsi_task *task = session->cmds[cmd_i];
1883 struct iscsi_tcp_task *tcp_task = task->dd_data;
1885 task->hdr = &tcp_task->hdr.cmd_hdr;
1886 task->hdr_max = sizeof(tcp_task->hdr) - ISCSI_DIGEST_SIZE;
1889 if (iscsi_r2tpool_alloc(session))
1890 goto remove_session;
1894 iscsi_session_teardown(cls_session);
1896 iscsi_host_remove(shost);
1898 iscsi_host_free(shost);
1902 static void iscsi_tcp_session_destroy(struct iscsi_cls_session *cls_session)
1904 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1906 iscsi_r2tpool_free(cls_session->dd_data);
1908 iscsi_host_remove(shost);
1909 iscsi_host_free(shost);
1912 static int iscsi_tcp_slave_configure(struct scsi_device *sdev)
1914 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY);
1915 blk_queue_dma_alignment(sdev->request_queue, 0);
1919 static struct scsi_host_template iscsi_sht = {
1920 .module = THIS_MODULE,
1921 .name = "iSCSI Initiator over TCP/IP",
1922 .queuecommand = iscsi_queuecommand,
1923 .change_queue_depth = iscsi_change_queue_depth,
1924 .can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1,
1925 .sg_tablesize = 4096,
1926 .max_sectors = 0xFFFF,
1927 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
1928 .eh_abort_handler = iscsi_eh_abort,
1929 .eh_device_reset_handler= iscsi_eh_device_reset,
1930 .eh_host_reset_handler = iscsi_eh_host_reset,
1931 .use_clustering = DISABLE_CLUSTERING,
1932 .slave_configure = iscsi_tcp_slave_configure,
1933 .proc_name = "iscsi_tcp",
1937 static struct iscsi_transport iscsi_tcp_transport = {
1938 .owner = THIS_MODULE,
1940 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
1942 .param_mask = ISCSI_MAX_RECV_DLENGTH |
1943 ISCSI_MAX_XMIT_DLENGTH |
1946 ISCSI_INITIAL_R2T_EN |
1951 ISCSI_PDU_INORDER_EN |
1952 ISCSI_DATASEQ_INORDER_EN |
1955 ISCSI_CONN_ADDRESS |
1957 ISCSI_PERSISTENT_PORT |
1958 ISCSI_PERSISTENT_ADDRESS |
1959 ISCSI_TARGET_NAME | ISCSI_TPGT |
1960 ISCSI_USERNAME | ISCSI_PASSWORD |
1961 ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN |
1962 ISCSI_FAST_ABORT | ISCSI_ABORT_TMO |
1963 ISCSI_LU_RESET_TMO |
1964 ISCSI_PING_TMO | ISCSI_RECV_TMO |
1965 ISCSI_IFACE_NAME | ISCSI_INITIATOR_NAME,
1966 .host_param_mask = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
1967 ISCSI_HOST_INITIATOR_NAME |
1968 ISCSI_HOST_NETDEV_NAME,
1969 /* session management */
1970 .create_session = iscsi_tcp_session_create,
1971 .destroy_session = iscsi_tcp_session_destroy,
1972 /* connection management */
1973 .create_conn = iscsi_tcp_conn_create,
1974 .bind_conn = iscsi_tcp_conn_bind,
1975 .destroy_conn = iscsi_tcp_conn_destroy,
1976 .set_param = iscsi_conn_set_param,
1977 .get_conn_param = iscsi_tcp_conn_get_param,
1978 .get_session_param = iscsi_session_get_param,
1979 .start_conn = iscsi_conn_start,
1980 .stop_conn = iscsi_tcp_conn_stop,
1981 /* iscsi host params */
1982 .get_host_param = iscsi_host_get_param,
1983 .set_host_param = iscsi_host_set_param,
1985 .send_pdu = iscsi_conn_send_pdu,
1986 .get_stats = iscsi_conn_get_stats,
1987 .init_task = iscsi_tcp_task_init,
1988 .xmit_task = iscsi_tcp_task_xmit,
1989 .cleanup_task = iscsi_tcp_cleanup_task,
1991 .session_recovery_timedout = iscsi_session_recovery_timedout,
1995 iscsi_tcp_init(void)
1997 if (iscsi_max_lun < 1) {
1998 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
2003 iscsi_tcp_scsi_transport = iscsi_register_transport(
2004 &iscsi_tcp_transport);
2005 if (!iscsi_tcp_scsi_transport)
2012 iscsi_tcp_exit(void)
2014 iscsi_unregister_transport(&iscsi_tcp_transport);
2017 module_init(iscsi_tcp_init);
2018 module_exit(iscsi_tcp_exit);