Merge branch 'docs-next' of git://git.lwn.net/linux-2.6
[linux-2.6] / drivers / scsi / cxgb3i / cxgb3i_iscsi.c
1 /* cxgb3i_iscsi.c: Chelsio S3xx iSCSI driver.
2  *
3  * Copyright (c) 2008 Chelsio Communications, Inc.
4  * Copyright (c) 2008 Mike Christie
5  * Copyright (c) 2008 Red Hat, Inc.  All rights reserved.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation.
10  *
11  * Written by: Karen Xie (kxie@chelsio.com)
12  */
13
14 #include <linux/inet.h>
15 #include <linux/crypto.h>
16 #include <net/dst.h>
17 #include <net/tcp.h>
18 #include <scsi/scsi_cmnd.h>
19 #include <scsi/scsi_device.h>
20 #include <scsi/scsi_eh.h>
21 #include <scsi/scsi_host.h>
22 #include <scsi/scsi.h>
23 #include <scsi/iscsi_proto.h>
24 #include <scsi/libiscsi.h>
25 #include <scsi/scsi_transport_iscsi.h>
26
27 #include "cxgb3i.h"
28 #include "cxgb3i_pdu.h"
29
30 #ifdef __DEBUG_CXGB3I_TAG__
31 #define cxgb3i_tag_debug        cxgb3i_log_debug
32 #else
33 #define cxgb3i_tag_debug(fmt...)
34 #endif
35
36 #ifdef __DEBUG_CXGB3I_API__
37 #define cxgb3i_api_debug        cxgb3i_log_debug
38 #else
39 #define cxgb3i_api_debug(fmt...)
40 #endif
41
42 /*
43  * align pdu size to multiple of 512 for better performance
44  */
45 #define align_pdu_size(n) do { n = (n) & (~511); } while (0)
46
47 static struct scsi_transport_template *cxgb3i_scsi_transport;
48 static struct scsi_host_template cxgb3i_host_template;
49 static struct iscsi_transport cxgb3i_iscsi_transport;
50 static unsigned char sw_tag_idx_bits;
51 static unsigned char sw_tag_age_bits;
52
53 static LIST_HEAD(cxgb3i_snic_list);
54 static DEFINE_RWLOCK(cxgb3i_snic_rwlock);
55
56 /**
57  * cxgb3i_adpater_find_by_tdev - find the cxgb3i_adapter structure via t3cdev
58  * @tdev: t3cdev pointer
59  */
60 struct cxgb3i_adapter *cxgb3i_adapter_find_by_tdev(struct t3cdev *tdev)
61 {
62         struct cxgb3i_adapter *snic;
63
64         read_lock(&cxgb3i_snic_rwlock);
65         list_for_each_entry(snic, &cxgb3i_snic_list, list_head) {
66                 if (snic->tdev == tdev) {
67                         read_unlock(&cxgb3i_snic_rwlock);
68                         return snic;
69                 }
70         }
71         read_unlock(&cxgb3i_snic_rwlock);
72         return NULL;
73 }
74
75 static inline int adapter_update(struct cxgb3i_adapter *snic)
76 {
77         cxgb3i_log_info("snic 0x%p, t3dev 0x%p, updating.\n",
78                         snic, snic->tdev);
79         return cxgb3i_adapter_ddp_info(snic->tdev, &snic->tag_format,
80                                         &snic->tx_max_size,
81                                         &snic->rx_max_size);
82 }
83
84 static int adapter_add(struct cxgb3i_adapter *snic)
85 {
86         struct t3cdev *t3dev = snic->tdev;
87         struct adapter *adapter = tdev2adap(t3dev);
88         int i, err;
89
90         snic->pdev = adapter->pdev;
91         snic->tag_format.sw_bits = sw_tag_idx_bits + sw_tag_age_bits;
92
93         err = cxgb3i_adapter_ddp_info(t3dev, &snic->tag_format,
94                                     &snic->tx_max_size,
95                                     &snic->rx_max_size);
96         if (err < 0)
97                 return err;
98
99         for_each_port(adapter, i) {
100                 snic->hba[i] = cxgb3i_hba_host_add(snic, adapter->port[i]);
101                 if (!snic->hba[i])
102                         return -EINVAL;
103         }
104         snic->hba_cnt = adapter->params.nports;
105
106         /* add to the list */
107         write_lock(&cxgb3i_snic_rwlock);
108         list_add_tail(&snic->list_head, &cxgb3i_snic_list);
109         write_unlock(&cxgb3i_snic_rwlock);
110
111         cxgb3i_log_info("t3dev 0x%p open, snic 0x%p, %u scsi hosts added.\n",
112                         t3dev, snic, snic->hba_cnt);
113         return 0;
114 }
115
116 /**
117  * cxgb3i_adapter_open - init a s3 adapter structure and any h/w settings
118  * @t3dev: t3cdev adapter
119  */
120 void cxgb3i_adapter_open(struct t3cdev *t3dev)
121 {
122         struct cxgb3i_adapter *snic = cxgb3i_adapter_find_by_tdev(t3dev);
123         int err;
124
125         if (snic)
126                 err = adapter_update(snic);
127         else {
128                 snic = kzalloc(sizeof(*snic), GFP_KERNEL);
129                 if (snic) {
130                         spin_lock_init(&snic->lock);
131                         snic->tdev = t3dev;
132                         err = adapter_add(snic);
133                 } else
134                         err = -ENOMEM;
135         }
136
137         if (err < 0) {
138                 cxgb3i_log_info("snic 0x%p, f 0x%x, t3dev 0x%p open, err %d.\n",
139                                 snic, snic ? snic->flags : 0, t3dev, err);
140                 if (snic) {
141                         snic->flags &= ~CXGB3I_ADAPTER_FLAG_RESET;
142                         cxgb3i_adapter_close(t3dev);
143                 }
144         }
145 }
146
147 /**
148  * cxgb3i_adapter_close - release the resources held and cleanup h/w settings
149  * @t3dev: t3cdev adapter
150  */
151 void cxgb3i_adapter_close(struct t3cdev *t3dev)
152 {
153         struct cxgb3i_adapter *snic = cxgb3i_adapter_find_by_tdev(t3dev);
154         int i;
155
156         if (!snic || snic->flags & CXGB3I_ADAPTER_FLAG_RESET) {
157                 cxgb3i_log_info("t3dev 0x%p close, snic 0x%p, f 0x%x.\n",
158                                 t3dev, snic, snic ? snic->flags : 0);
159                 return;
160         }
161
162         /* remove from the list */
163         write_lock(&cxgb3i_snic_rwlock);
164         list_del(&snic->list_head);
165         write_unlock(&cxgb3i_snic_rwlock);
166
167         for (i = 0; i < snic->hba_cnt; i++) {
168                 if (snic->hba[i]) {
169                         cxgb3i_hba_host_remove(snic->hba[i]);
170                         snic->hba[i] = NULL;
171                 }
172         }
173         cxgb3i_log_info("t3dev 0x%p close, snic 0x%p, %u scsi hosts removed.\n",
174                         t3dev, snic, snic->hba_cnt);
175         kfree(snic);
176 }
177
178 /**
179  * cxgb3i_hba_find_by_netdev - find the cxgb3i_hba structure via net_device
180  * @t3dev: t3cdev adapter
181  */
182 static struct cxgb3i_hba *cxgb3i_hba_find_by_netdev(struct net_device *ndev)
183 {
184         struct cxgb3i_adapter *snic;
185         int i;
186
187         read_lock(&cxgb3i_snic_rwlock);
188         list_for_each_entry(snic, &cxgb3i_snic_list, list_head) {
189                 for (i = 0; i < snic->hba_cnt; i++) {
190                         if (snic->hba[i]->ndev == ndev) {
191                                 read_unlock(&cxgb3i_snic_rwlock);
192                                 return snic->hba[i];
193                         }
194                 }
195         }
196         read_unlock(&cxgb3i_snic_rwlock);
197         return NULL;
198 }
199
200 /**
201  * cxgb3i_hba_host_add - register a new host with scsi/iscsi
202  * @snic: the cxgb3i adapter
203  * @ndev: associated net_device
204  */
205 struct cxgb3i_hba *cxgb3i_hba_host_add(struct cxgb3i_adapter *snic,
206                                        struct net_device *ndev)
207 {
208         struct cxgb3i_hba *hba;
209         struct Scsi_Host *shost;
210         int err;
211
212         shost = iscsi_host_alloc(&cxgb3i_host_template,
213                                  sizeof(struct cxgb3i_hba), 1);
214         if (!shost) {
215                 cxgb3i_log_info("snic 0x%p, ndev 0x%p, host_alloc failed.\n",
216                                 snic, ndev);
217                 return NULL;
218         }
219
220         shost->transportt = cxgb3i_scsi_transport;
221         shost->max_lun = CXGB3I_MAX_LUN;
222         shost->max_id = CXGB3I_MAX_TARGET;
223         shost->max_channel = 0;
224         shost->max_cmd_len = 16;
225
226         hba = iscsi_host_priv(shost);
227         hba->snic = snic;
228         hba->ndev = ndev;
229         hba->shost = shost;
230
231         pci_dev_get(snic->pdev);
232         err = iscsi_host_add(shost, &snic->pdev->dev);
233         if (err) {
234                 cxgb3i_log_info("snic 0x%p, ndev 0x%p, host_add failed.\n",
235                                 snic, ndev);
236                 goto pci_dev_put;
237         }
238
239         cxgb3i_api_debug("shost 0x%p, hba 0x%p, no %u.\n",
240                          shost, hba, shost->host_no);
241
242         return hba;
243
244 pci_dev_put:
245         pci_dev_put(snic->pdev);
246         scsi_host_put(shost);
247         return NULL;
248 }
249
250 /**
251  * cxgb3i_hba_host_remove - de-register the host with scsi/iscsi
252  * @hba: the cxgb3i hba
253  */
254 void cxgb3i_hba_host_remove(struct cxgb3i_hba *hba)
255 {
256         cxgb3i_api_debug("shost 0x%p, hba 0x%p, no %u.\n",
257                          hba->shost, hba, hba->shost->host_no);
258         iscsi_host_remove(hba->shost);
259         pci_dev_put(hba->snic->pdev);
260         iscsi_host_free(hba->shost);
261 }
262
263 /**
264  * cxgb3i_ep_connect - establish TCP connection to target portal
265  * @shost:              scsi host to use
266  * @dst_addr:           target IP address
267  * @non_blocking:       blocking or non-blocking call
268  *
269  * Initiates a TCP/IP connection to the dst_addr
270  */
271 static struct iscsi_endpoint *cxgb3i_ep_connect(struct Scsi_Host *shost,
272                                                 struct sockaddr *dst_addr,
273                                                 int non_blocking)
274 {
275         struct iscsi_endpoint *ep;
276         struct cxgb3i_endpoint *cep;
277         struct cxgb3i_hba *hba = NULL;
278         struct s3_conn *c3cn = NULL;
279         int err = 0;
280
281         if (shost)
282                 hba = iscsi_host_priv(shost);
283
284         cxgb3i_api_debug("shost 0x%p, hba 0x%p.\n", shost, hba);
285
286         c3cn = cxgb3i_c3cn_create();
287         if (!c3cn) {
288                 cxgb3i_log_info("ep connect OOM.\n");
289                 err = -ENOMEM;
290                 goto release_conn;
291         }
292
293         err = cxgb3i_c3cn_connect(hba ? hba->ndev : NULL, c3cn,
294                                  (struct sockaddr_in *)dst_addr);
295         if (err < 0) {
296                 cxgb3i_log_info("ep connect failed.\n");
297                 goto release_conn;
298         }
299
300         hba = cxgb3i_hba_find_by_netdev(c3cn->dst_cache->dev);
301         if (!hba) {
302                 err = -ENOSPC;
303                 cxgb3i_log_info("NOT going through cxgbi device.\n");
304                 goto release_conn;
305         }
306
307         if (shost && hba != iscsi_host_priv(shost)) {
308                 err = -ENOSPC;
309                 cxgb3i_log_info("Could not connect through request host%u\n",
310                                 shost->host_no);
311                 goto release_conn;
312         }
313
314         if (c3cn_is_closing(c3cn)) {
315                 err = -ENOSPC;
316                 cxgb3i_log_info("ep connect unable to connect.\n");
317                 goto release_conn;
318         }
319
320         ep = iscsi_create_endpoint(sizeof(*cep));
321         if (!ep) {
322                 err = -ENOMEM;
323                 cxgb3i_log_info("iscsi alloc ep, OOM.\n");
324                 goto release_conn;
325         }
326         cep = ep->dd_data;
327         cep->c3cn = c3cn;
328         cep->hba = hba;
329
330         cxgb3i_api_debug("ep 0x%p, 0x%p, c3cn 0x%p, hba 0x%p.\n",
331                           ep, cep, c3cn, hba);
332         return ep;
333
334 release_conn:
335         cxgb3i_api_debug("conn 0x%p failed, release.\n", c3cn);
336         if (c3cn)
337                 cxgb3i_c3cn_release(c3cn);
338         return ERR_PTR(err);
339 }
340
341 /**
342  * cxgb3i_ep_poll - polls for TCP connection establishement
343  * @ep:         TCP connection (endpoint) handle
344  * @timeout_ms: timeout value in milli secs
345  *
346  * polls for TCP connect request to complete
347  */
348 static int cxgb3i_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
349 {
350         struct cxgb3i_endpoint *cep = ep->dd_data;
351         struct s3_conn *c3cn = cep->c3cn;
352
353         if (!c3cn_is_established(c3cn))
354                 return 0;
355         cxgb3i_api_debug("ep 0x%p, c3cn 0x%p established.\n", ep, c3cn);
356         return 1;
357 }
358
359 /**
360  * cxgb3i_ep_disconnect - teardown TCP connection
361  * @ep:         TCP connection (endpoint) handle
362  *
363  * teardown TCP connection
364  */
365 static void cxgb3i_ep_disconnect(struct iscsi_endpoint *ep)
366 {
367         struct cxgb3i_endpoint *cep = ep->dd_data;
368         struct cxgb3i_conn *cconn = cep->cconn;
369
370         cxgb3i_api_debug("ep 0x%p, cep 0x%p.\n", ep, cep);
371
372         if (cconn && cconn->conn) {
373                 /*
374                  * stop the xmit path so the xmit_pdu function is
375                  * not being called
376                  */
377                 iscsi_suspend_tx(cconn->conn);
378
379                 write_lock_bh(&cep->c3cn->callback_lock);
380                 cep->c3cn->user_data = NULL;
381                 cconn->cep = NULL;
382                 write_unlock_bh(&cep->c3cn->callback_lock);
383         }
384
385         cxgb3i_api_debug("ep 0x%p, cep 0x%p, release c3cn 0x%p.\n",
386                          ep, cep, cep->c3cn);
387         cxgb3i_c3cn_release(cep->c3cn);
388         iscsi_destroy_endpoint(ep);
389 }
390
391 /**
392  * cxgb3i_session_create - create a new iscsi session
393  * @cmds_max:           max # of commands
394  * @qdepth:             scsi queue depth
395  * @initial_cmdsn:      initial iscsi CMDSN for this session
396  *
397  * Creates a new iSCSI session
398  */
399 static struct iscsi_cls_session *
400 cxgb3i_session_create(struct iscsi_endpoint *ep, u16 cmds_max, u16 qdepth,
401                       u32 initial_cmdsn)
402 {
403         struct cxgb3i_endpoint *cep;
404         struct cxgb3i_hba *hba;
405         struct Scsi_Host *shost;
406         struct iscsi_cls_session *cls_session;
407         struct iscsi_session *session;
408
409         if (!ep) {
410                 cxgb3i_log_error("%s, missing endpoint.\n", __func__);
411                 return NULL;
412         }
413
414         cep = ep->dd_data;
415         hba = cep->hba;
416         shost = hba->shost;
417         cxgb3i_api_debug("ep 0x%p, cep 0x%p, hba 0x%p.\n", ep, cep, hba);
418         BUG_ON(hba != iscsi_host_priv(shost));
419
420         cls_session = iscsi_session_setup(&cxgb3i_iscsi_transport, shost,
421                                           cmds_max,
422                                           sizeof(struct iscsi_tcp_task) +
423                                           sizeof(struct cxgb3i_task_data),
424                                           initial_cmdsn, ISCSI_MAX_TARGET);
425         if (!cls_session)
426                 return NULL;
427         session = cls_session->dd_data;
428         if (iscsi_tcp_r2tpool_alloc(session))
429                 goto remove_session;
430
431         return cls_session;
432
433 remove_session:
434         iscsi_session_teardown(cls_session);
435         return NULL;
436 }
437
438 /**
439  * cxgb3i_session_destroy - destroys iscsi session
440  * @cls_session:        pointer to iscsi cls session
441  *
442  * Destroys an iSCSI session instance and releases its all resources held
443  */
444 static void cxgb3i_session_destroy(struct iscsi_cls_session *cls_session)
445 {
446         cxgb3i_api_debug("sess 0x%p.\n", cls_session);
447         iscsi_tcp_r2tpool_free(cls_session->dd_data);
448         iscsi_session_teardown(cls_session);
449 }
450
451 /**
452  * cxgb3i_conn_max_xmit_dlength -- calc the max. xmit pdu segment size
453  * @conn: iscsi connection
454  * check the max. xmit pdu payload, reduce it if needed
455  */
456 static inline int cxgb3i_conn_max_xmit_dlength(struct iscsi_conn *conn)
457
458 {
459         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
460         struct cxgb3i_conn *cconn = tcp_conn->dd_data;
461         unsigned int max = max(512 * MAX_SKB_FRAGS, SKB_TX_HEADROOM);
462
463         max = min(cconn->hba->snic->tx_max_size, max);
464         if (conn->max_xmit_dlength)
465                 conn->max_xmit_dlength = min(conn->max_xmit_dlength, max);
466         else
467                 conn->max_xmit_dlength = max;
468         align_pdu_size(conn->max_xmit_dlength);
469         cxgb3i_api_debug("conn 0x%p, max xmit %u.\n",
470                          conn, conn->max_xmit_dlength);
471         return 0;
472 }
473
474 /**
475  * cxgb3i_conn_max_recv_dlength -- check the max. recv pdu segment size
476  * @conn: iscsi connection
477  * return 0 if the value is valid, < 0 otherwise.
478  */
479 static inline int cxgb3i_conn_max_recv_dlength(struct iscsi_conn *conn)
480 {
481         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
482         struct cxgb3i_conn *cconn = tcp_conn->dd_data;
483         unsigned int max = cconn->hba->snic->rx_max_size;
484
485         align_pdu_size(max);
486         if (conn->max_recv_dlength) {
487                 if (conn->max_recv_dlength > max) {
488                         cxgb3i_log_error("MaxRecvDataSegmentLength %u too big."
489                                          " Need to be <= %u.\n",
490                                          conn->max_recv_dlength, max);
491                         return -EINVAL;
492                 }
493                 conn->max_recv_dlength = min(conn->max_recv_dlength, max);
494                 align_pdu_size(conn->max_recv_dlength);
495         } else
496                 conn->max_recv_dlength = max;
497         cxgb3i_api_debug("conn 0x%p, max recv %u.\n",
498                          conn, conn->max_recv_dlength);
499         return 0;
500 }
501
502 /**
503  * cxgb3i_conn_create - create iscsi connection instance
504  * @cls_session:        pointer to iscsi cls session
505  * @cid:                iscsi cid
506  *
507  * Creates a new iSCSI connection instance for a given session
508  */
509 static struct iscsi_cls_conn *cxgb3i_conn_create(struct iscsi_cls_session
510                                                  *cls_session, u32 cid)
511 {
512         struct iscsi_cls_conn *cls_conn;
513         struct iscsi_conn *conn;
514         struct iscsi_tcp_conn *tcp_conn;
515         struct cxgb3i_conn *cconn;
516
517         cxgb3i_api_debug("sess 0x%p, cid %u.\n", cls_session, cid);
518
519         cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*cconn), cid);
520         if (!cls_conn)
521                 return NULL;
522         conn = cls_conn->dd_data;
523         tcp_conn = conn->dd_data;
524         cconn = tcp_conn->dd_data;
525
526         cconn->conn = conn;
527         return cls_conn;
528 }
529
530 /**
531  * cxgb3i_conn_bind - binds iscsi sess, conn and endpoint together
532  * @cls_session:        pointer to iscsi cls session
533  * @cls_conn:           pointer to iscsi cls conn
534  * @transport_eph:      64-bit EP handle
535  * @is_leading:         leading connection on this session?
536  *
537  * Binds together an iSCSI session, an iSCSI connection and a
538  *      TCP connection. This routine returns error code if the TCP
539  *      connection does not belong on the device iSCSI sess/conn is bound
540  */
541
542 static int cxgb3i_conn_bind(struct iscsi_cls_session *cls_session,
543                             struct iscsi_cls_conn *cls_conn,
544                             u64 transport_eph, int is_leading)
545 {
546         struct iscsi_conn *conn = cls_conn->dd_data;
547         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
548         struct cxgb3i_conn *cconn = tcp_conn->dd_data;
549         struct cxgb3i_adapter *snic;
550         struct iscsi_endpoint *ep;
551         struct cxgb3i_endpoint *cep;
552         struct s3_conn *c3cn;
553         int err;
554
555         ep = iscsi_lookup_endpoint(transport_eph);
556         if (!ep)
557                 return -EINVAL;
558
559         /* setup ddp pagesize */
560         cep = ep->dd_data;
561         c3cn = cep->c3cn;
562         snic = cep->hba->snic;
563         err = cxgb3i_setup_conn_host_pagesize(snic->tdev, c3cn->tid, 0);
564         if (err < 0)
565                 return err;
566
567         cxgb3i_api_debug("ep 0x%p, cls sess 0x%p, cls conn 0x%p.\n",
568                          ep, cls_session, cls_conn);
569
570         err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
571         if (err)
572                 return -EINVAL;
573
574         /* calculate the tag idx bits needed for this conn based on cmds_max */
575         cconn->task_idx_bits = (__ilog2_u32(conn->session->cmds_max - 1)) + 1;
576         cxgb3i_api_debug("session cmds_max 0x%x, bits %u.\n",
577                          conn->session->cmds_max, cconn->task_idx_bits);
578
579         read_lock(&c3cn->callback_lock);
580         c3cn->user_data = conn;
581         cconn->hba = cep->hba;
582         cconn->cep = cep;
583         cep->cconn = cconn;
584         read_unlock(&c3cn->callback_lock);
585
586         cxgb3i_conn_max_xmit_dlength(conn);
587         cxgb3i_conn_max_recv_dlength(conn);
588
589         spin_lock_bh(&conn->session->lock);
590         sprintf(conn->portal_address, NIPQUAD_FMT,
591                 NIPQUAD(c3cn->daddr.sin_addr.s_addr));
592         conn->portal_port = ntohs(c3cn->daddr.sin_port);
593         spin_unlock_bh(&conn->session->lock);
594
595         /* init recv engine */
596         iscsi_tcp_hdr_recv_prep(tcp_conn);
597
598         return 0;
599 }
600
601 /**
602  * cxgb3i_conn_get_param - return iscsi connection parameter to caller
603  * @cls_conn:   pointer to iscsi cls conn
604  * @param:      parameter type identifier
605  * @buf:        buffer pointer
606  *
607  * returns iSCSI connection parameters
608  */
609 static int cxgb3i_conn_get_param(struct iscsi_cls_conn *cls_conn,
610                                  enum iscsi_param param, char *buf)
611 {
612         struct iscsi_conn *conn = cls_conn->dd_data;
613         int len;
614
615         cxgb3i_api_debug("cls_conn 0x%p, param %d.\n", cls_conn, param);
616
617         switch (param) {
618         case ISCSI_PARAM_CONN_PORT:
619                 spin_lock_bh(&conn->session->lock);
620                 len = sprintf(buf, "%hu\n", conn->portal_port);
621                 spin_unlock_bh(&conn->session->lock);
622                 break;
623         case ISCSI_PARAM_CONN_ADDRESS:
624                 spin_lock_bh(&conn->session->lock);
625                 len = sprintf(buf, "%s\n", conn->portal_address);
626                 spin_unlock_bh(&conn->session->lock);
627                 break;
628         default:
629                 return iscsi_conn_get_param(cls_conn, param, buf);
630         }
631
632         return len;
633 }
634
635 /**
636  * cxgb3i_conn_set_param - set iscsi connection parameter
637  * @cls_conn:   pointer to iscsi cls conn
638  * @param:      parameter type identifier
639  * @buf:        buffer pointer
640  * @buflen:     buffer length
641  *
642  * set iSCSI connection parameters
643  */
644 static int cxgb3i_conn_set_param(struct iscsi_cls_conn *cls_conn,
645                                  enum iscsi_param param, char *buf, int buflen)
646 {
647         struct iscsi_conn *conn = cls_conn->dd_data;
648         struct iscsi_session *session = conn->session;
649         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
650         struct cxgb3i_conn *cconn = tcp_conn->dd_data;
651         struct cxgb3i_adapter *snic = cconn->hba->snic;
652         struct s3_conn *c3cn = cconn->cep->c3cn;
653         int value, err = 0;
654
655         switch (param) {
656         case ISCSI_PARAM_HDRDGST_EN:
657                 err = iscsi_set_param(cls_conn, param, buf, buflen);
658                 if (!err && conn->hdrdgst_en)
659                         err = cxgb3i_setup_conn_digest(snic->tdev, c3cn->tid,
660                                                         conn->hdrdgst_en,
661                                                         conn->datadgst_en, 0);
662                 break;
663         case ISCSI_PARAM_DATADGST_EN:
664                 err = iscsi_set_param(cls_conn, param, buf, buflen);
665                 if (!err && conn->datadgst_en)
666                         err = cxgb3i_setup_conn_digest(snic->tdev, c3cn->tid,
667                                                         conn->hdrdgst_en,
668                                                         conn->datadgst_en, 0);
669                 break;
670         case ISCSI_PARAM_MAX_R2T:
671                 sscanf(buf, "%d", &value);
672                 if (value <= 0 || !is_power_of_2(value))
673                         return -EINVAL;
674                 if (session->max_r2t == value)
675                         break;
676                 iscsi_tcp_r2tpool_free(session);
677                 err = iscsi_set_param(cls_conn, param, buf, buflen);
678                 if (!err && iscsi_tcp_r2tpool_alloc(session))
679                         return -ENOMEM;
680         case ISCSI_PARAM_MAX_RECV_DLENGTH:
681                 err = iscsi_set_param(cls_conn, param, buf, buflen);
682                 if (!err)
683                         err = cxgb3i_conn_max_recv_dlength(conn);
684                 break;
685         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
686                 err = iscsi_set_param(cls_conn, param, buf, buflen);
687                 if (!err)
688                         err = cxgb3i_conn_max_xmit_dlength(conn);
689                 break;
690         default:
691                 return iscsi_set_param(cls_conn, param, buf, buflen);
692         }
693         return err;
694 }
695
696 /**
697  * cxgb3i_host_set_param - configure host (adapter) related parameters
698  * @shost:      scsi host pointer
699  * @param:      parameter type identifier
700  * @buf:        buffer pointer
701  */
702 static int cxgb3i_host_set_param(struct Scsi_Host *shost,
703                                  enum iscsi_host_param param,
704                                  char *buf, int buflen)
705 {
706         struct cxgb3i_hba *hba = iscsi_host_priv(shost);
707
708         cxgb3i_api_debug("param %d, buf %s.\n", param, buf);
709
710         switch (param) {
711         case ISCSI_HOST_PARAM_IPADDRESS:
712         {
713                 __be32 addr = in_aton(buf);
714                 cxgb3i_set_private_ipv4addr(hba->ndev, addr);
715                 return 0;
716         }
717         case ISCSI_HOST_PARAM_HWADDRESS:
718         case ISCSI_HOST_PARAM_NETDEV_NAME:
719                 /* ignore */
720                 return 0;
721         default:
722                 return iscsi_host_set_param(shost, param, buf, buflen);
723         }
724 }
725
726 /**
727  * cxgb3i_host_get_param - returns host (adapter) related parameters
728  * @shost:      scsi host pointer
729  * @param:      parameter type identifier
730  * @buf:        buffer pointer
731  */
732 static int cxgb3i_host_get_param(struct Scsi_Host *shost,
733                                  enum iscsi_host_param param, char *buf)
734 {
735         struct cxgb3i_hba *hba = iscsi_host_priv(shost);
736         int len = 0;
737
738         cxgb3i_api_debug("hba %s, param %d.\n", hba->ndev->name, param);
739
740         switch (param) {
741         case ISCSI_HOST_PARAM_HWADDRESS:
742                 len = sysfs_format_mac(buf, hba->ndev->dev_addr, 6);
743                 break;
744         case ISCSI_HOST_PARAM_NETDEV_NAME:
745                 len = sprintf(buf, "%s\n", hba->ndev->name);
746                 break;
747         case ISCSI_HOST_PARAM_IPADDRESS:
748         {
749                 __be32 addr;
750
751                 addr = cxgb3i_get_private_ipv4addr(hba->ndev);
752                 len = sprintf(buf, NIPQUAD_FMT, NIPQUAD(addr));
753                 break;
754         }
755         default:
756                 return iscsi_host_get_param(shost, param, buf);
757         }
758         return len;
759 }
760
761 /**
762  * cxgb3i_conn_get_stats - returns iSCSI stats
763  * @cls_conn:   pointer to iscsi cls conn
764  * @stats:      pointer to iscsi statistic struct
765  */
766 static void cxgb3i_conn_get_stats(struct iscsi_cls_conn *cls_conn,
767                                   struct iscsi_stats *stats)
768 {
769         struct iscsi_conn *conn = cls_conn->dd_data;
770
771         stats->txdata_octets = conn->txdata_octets;
772         stats->rxdata_octets = conn->rxdata_octets;
773         stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
774         stats->dataout_pdus = conn->dataout_pdus_cnt;
775         stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
776         stats->datain_pdus = conn->datain_pdus_cnt;
777         stats->r2t_pdus = conn->r2t_pdus_cnt;
778         stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
779         stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
780         stats->digest_err = 0;
781         stats->timeout_err = 0;
782         stats->custom_length = 1;
783         strcpy(stats->custom[0].desc, "eh_abort_cnt");
784         stats->custom[0].value = conn->eh_abort_cnt;
785 }
786
787 /**
788  * cxgb3i_parse_itt - get the idx and age bits from a given tag
789  * @conn:       iscsi connection
790  * @itt:        itt tag
791  * @idx:        task index, filled in by this function
792  * @age:        session age, filled in by this function
793  */
794 static void cxgb3i_parse_itt(struct iscsi_conn *conn, itt_t itt,
795                              int *idx, int *age)
796 {
797         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
798         struct cxgb3i_conn *cconn = tcp_conn->dd_data;
799         struct cxgb3i_adapter *snic = cconn->hba->snic;
800         u32 tag = ntohl((__force u32) itt);
801         u32 sw_bits;
802
803         sw_bits = cxgb3i_tag_nonrsvd_bits(&snic->tag_format, tag);
804         if (idx)
805                 *idx = sw_bits & ((1 << cconn->task_idx_bits) - 1);
806         if (age)
807                 *age = (sw_bits >> cconn->task_idx_bits) & ISCSI_AGE_MASK;
808
809         cxgb3i_tag_debug("parse tag 0x%x/0x%x, sw 0x%x, itt 0x%x, age 0x%x.\n",
810                          tag, itt, sw_bits, idx ? *idx : 0xFFFFF,
811                          age ? *age : 0xFF);
812 }
813
814 /**
815  * cxgb3i_reserve_itt - generate tag for a give task
816  * @task: iscsi task
817  * @hdr_itt: tag, filled in by this function
818  * Set up ddp for scsi read tasks if possible.
819  */
820 int cxgb3i_reserve_itt(struct iscsi_task *task, itt_t *hdr_itt)
821 {
822         struct scsi_cmnd *sc = task->sc;
823         struct iscsi_conn *conn = task->conn;
824         struct iscsi_session *sess = conn->session;
825         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
826         struct cxgb3i_conn *cconn = tcp_conn->dd_data;
827         struct cxgb3i_adapter *snic = cconn->hba->snic;
828         struct cxgb3i_tag_format *tformat = &snic->tag_format;
829         u32 sw_tag = (sess->age << cconn->task_idx_bits) | task->itt;
830         u32 tag;
831         int err = -EINVAL;
832
833         if (sc &&
834             (scsi_bidi_cmnd(sc) || sc->sc_data_direction == DMA_FROM_DEVICE) &&
835             cxgb3i_sw_tag_usable(tformat, sw_tag)) {
836                 struct s3_conn *c3cn = cconn->cep->c3cn;
837                 struct cxgb3i_gather_list *gl;
838
839                 gl = cxgb3i_ddp_make_gl(scsi_in(sc)->length,
840                                         scsi_in(sc)->table.sgl,
841                                         scsi_in(sc)->table.nents,
842                                         snic->pdev,
843                                         GFP_ATOMIC);
844                 if (gl) {
845                         tag = sw_tag;
846                         err = cxgb3i_ddp_tag_reserve(snic->tdev, c3cn->tid,
847                                                      tformat, &tag,
848                                                      gl, GFP_ATOMIC);
849                         if (err < 0)
850                                 cxgb3i_ddp_release_gl(gl, snic->pdev);
851                 }
852         }
853
854         if (err < 0)
855                 tag = cxgb3i_set_non_ddp_tag(tformat, sw_tag);
856         /* the itt need to sent in big-endian order */
857         *hdr_itt = (__force itt_t)htonl(tag);
858
859         cxgb3i_tag_debug("new tag 0x%x/0x%x (itt 0x%x, age 0x%x).\n",
860                          tag, *hdr_itt, task->itt, sess->age);
861         return 0;
862 }
863
864 /**
865  * cxgb3i_release_itt - release the tag for a given task
866  * @task:       iscsi task
867  * @hdr_itt:    tag
868  * If the tag is a ddp tag, release the ddp setup
869  */
870 void cxgb3i_release_itt(struct iscsi_task *task, itt_t hdr_itt)
871 {
872         struct scsi_cmnd *sc = task->sc;
873         struct iscsi_tcp_conn *tcp_conn = task->conn->dd_data;
874         struct cxgb3i_conn *cconn = tcp_conn->dd_data;
875         struct cxgb3i_adapter *snic = cconn->hba->snic;
876         struct cxgb3i_tag_format *tformat = &snic->tag_format;
877         u32 tag = ntohl((__force u32)hdr_itt);
878
879         cxgb3i_tag_debug("release tag 0x%x.\n", tag);
880
881         if (sc &&
882             (scsi_bidi_cmnd(sc) || sc->sc_data_direction == DMA_FROM_DEVICE) &&
883             cxgb3i_is_ddp_tag(tformat, tag))
884                 cxgb3i_ddp_tag_release(snic->tdev, tag);
885 }
886
887 /**
888  * cxgb3i_host_template -- Scsi_Host_Template structure
889  *      used when registering with the scsi mid layer
890  */
891 static struct scsi_host_template cxgb3i_host_template = {
892         .module                 = THIS_MODULE,
893         .name                   = "Chelsio S3xx iSCSI Initiator",
894         .proc_name              = "cxgb3i",
895         .queuecommand           = iscsi_queuecommand,
896         .change_queue_depth     = iscsi_change_queue_depth,
897         .can_queue              = CXGB3I_SCSI_HOST_QDEPTH,
898         .sg_tablesize           = SG_ALL,
899         .max_sectors            = 0xFFFF,
900         .cmd_per_lun            = ISCSI_DEF_CMD_PER_LUN,
901         .eh_abort_handler       = iscsi_eh_abort,
902         .eh_device_reset_handler = iscsi_eh_device_reset,
903         .eh_target_reset_handler = iscsi_eh_target_reset,
904         .target_alloc           = iscsi_target_alloc,
905         .use_clustering         = DISABLE_CLUSTERING,
906         .this_id                = -1,
907 };
908
909 static struct iscsi_transport cxgb3i_iscsi_transport = {
910         .owner                  = THIS_MODULE,
911         .name                   = "cxgb3i",
912         .caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
913                                 | CAP_DATADGST | CAP_DIGEST_OFFLOAD |
914                                 CAP_PADDING_OFFLOAD,
915         .param_mask             = ISCSI_MAX_RECV_DLENGTH |
916                                 ISCSI_MAX_XMIT_DLENGTH |
917                                 ISCSI_HDRDGST_EN |
918                                 ISCSI_DATADGST_EN |
919                                 ISCSI_INITIAL_R2T_EN |
920                                 ISCSI_MAX_R2T |
921                                 ISCSI_IMM_DATA_EN |
922                                 ISCSI_FIRST_BURST |
923                                 ISCSI_MAX_BURST |
924                                 ISCSI_PDU_INORDER_EN |
925                                 ISCSI_DATASEQ_INORDER_EN |
926                                 ISCSI_ERL |
927                                 ISCSI_CONN_PORT |
928                                 ISCSI_CONN_ADDRESS |
929                                 ISCSI_EXP_STATSN |
930                                 ISCSI_PERSISTENT_PORT |
931                                 ISCSI_PERSISTENT_ADDRESS |
932                                 ISCSI_TARGET_NAME | ISCSI_TPGT |
933                                 ISCSI_USERNAME | ISCSI_PASSWORD |
934                                 ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN |
935                                 ISCSI_FAST_ABORT | ISCSI_ABORT_TMO |
936                                 ISCSI_LU_RESET_TMO |
937                                 ISCSI_PING_TMO | ISCSI_RECV_TMO |
938                                 ISCSI_IFACE_NAME | ISCSI_INITIATOR_NAME,
939         .host_param_mask        = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
940                         ISCSI_HOST_INITIATOR_NAME | ISCSI_HOST_NETDEV_NAME,
941         .get_host_param         = cxgb3i_host_get_param,
942         .set_host_param         = cxgb3i_host_set_param,
943         /* session management */
944         .create_session         = cxgb3i_session_create,
945         .destroy_session        = cxgb3i_session_destroy,
946         .get_session_param      = iscsi_session_get_param,
947         /* connection management */
948         .create_conn            = cxgb3i_conn_create,
949         .bind_conn              = cxgb3i_conn_bind,
950         .destroy_conn           = iscsi_tcp_conn_teardown,
951         .start_conn             = iscsi_conn_start,
952         .stop_conn              = iscsi_conn_stop,
953         .get_conn_param         = cxgb3i_conn_get_param,
954         .set_param              = cxgb3i_conn_set_param,
955         .get_stats              = cxgb3i_conn_get_stats,
956         /* pdu xmit req. from user space */
957         .send_pdu               = iscsi_conn_send_pdu,
958         /* task */
959         .init_task              = iscsi_tcp_task_init,
960         .xmit_task              = iscsi_tcp_task_xmit,
961         .cleanup_task           = cxgb3i_conn_cleanup_task,
962
963         /* pdu */
964         .alloc_pdu              = cxgb3i_conn_alloc_pdu,
965         .init_pdu               = cxgb3i_conn_init_pdu,
966         .xmit_pdu               = cxgb3i_conn_xmit_pdu,
967         .parse_pdu_itt          = cxgb3i_parse_itt,
968
969         /* TCP connect/disconnect */
970         .ep_connect             = cxgb3i_ep_connect,
971         .ep_poll                = cxgb3i_ep_poll,
972         .ep_disconnect          = cxgb3i_ep_disconnect,
973         /* Error recovery timeout call */
974         .session_recovery_timedout = iscsi_session_recovery_timedout,
975 };
976
977 int cxgb3i_iscsi_init(void)
978 {
979         sw_tag_idx_bits = (__ilog2_u32(ISCSI_ITT_MASK)) + 1;
980         sw_tag_age_bits = (__ilog2_u32(ISCSI_AGE_MASK)) + 1;
981         cxgb3i_log_info("tag itt 0x%x, %u bits, age 0x%x, %u bits.\n",
982                         ISCSI_ITT_MASK, sw_tag_idx_bits,
983                         ISCSI_AGE_MASK, sw_tag_age_bits);
984
985         cxgb3i_scsi_transport =
986             iscsi_register_transport(&cxgb3i_iscsi_transport);
987         if (!cxgb3i_scsi_transport) {
988                 cxgb3i_log_error("Could not register cxgb3i transport.\n");
989                 return -ENODEV;
990         }
991         cxgb3i_api_debug("cxgb3i transport 0x%p.\n", cxgb3i_scsi_transport);
992         return 0;
993 }
994
995 void cxgb3i_iscsi_cleanup(void)
996 {
997         if (cxgb3i_scsi_transport) {
998                 cxgb3i_api_debug("cxgb3i transport 0x%p.\n",
999                                  cxgb3i_scsi_transport);
1000                 iscsi_unregister_transport(&cxgb3i_iscsi_transport);
1001         }
1002 }