Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs...
[pandora-kernel.git] / drivers / infiniband / ulp / srp / ib_srp.c
1 /*
2  * Copyright (c) 2005 Cisco Systems.  All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32
33 #include <linux/module.h>
34 #include <linux/init.h>
35 #include <linux/slab.h>
36 #include <linux/err.h>
37 #include <linux/string.h>
38 #include <linux/parser.h>
39 #include <linux/random.h>
40 #include <linux/jiffies.h>
41
42 #include <asm/atomic.h>
43
44 #include <scsi/scsi.h>
45 #include <scsi/scsi_device.h>
46 #include <scsi/scsi_dbg.h>
47 #include <scsi/srp.h>
48 #include <scsi/scsi_transport_srp.h>
49
50 #include "ib_srp.h"
51
52 #define DRV_NAME        "ib_srp"
53 #define PFX             DRV_NAME ": "
54 #define DRV_VERSION     "0.2"
55 #define DRV_RELDATE     "November 1, 2005"
56
57 MODULE_AUTHOR("Roland Dreier");
58 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
59                    "v" DRV_VERSION " (" DRV_RELDATE ")");
60 MODULE_LICENSE("Dual BSD/GPL");
61
62 static int srp_sg_tablesize = SRP_DEF_SG_TABLESIZE;
63 static int srp_max_iu_len;
64
65 module_param(srp_sg_tablesize, int, 0444);
66 MODULE_PARM_DESC(srp_sg_tablesize,
67                  "Max number of gather/scatter entries per I/O (default is 12, max 255)");
68
69 static int topspin_workarounds = 1;
70
71 module_param(topspin_workarounds, int, 0444);
72 MODULE_PARM_DESC(topspin_workarounds,
73                  "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
74
75 static int mellanox_workarounds = 1;
76
77 module_param(mellanox_workarounds, int, 0444);
78 MODULE_PARM_DESC(mellanox_workarounds,
79                  "Enable workarounds for Mellanox SRP target bugs if != 0");
80
81 static void srp_add_one(struct ib_device *device);
82 static void srp_remove_one(struct ib_device *device);
83 static void srp_recv_completion(struct ib_cq *cq, void *target_ptr);
84 static void srp_send_completion(struct ib_cq *cq, void *target_ptr);
85 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
86
87 static struct scsi_transport_template *ib_srp_transport_template;
88
89 static struct ib_client srp_client = {
90         .name   = "srp",
91         .add    = srp_add_one,
92         .remove = srp_remove_one
93 };
94
95 static struct ib_sa_client srp_sa_client;
96
97 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
98 {
99         return (struct srp_target_port *) host->hostdata;
100 }
101
102 static const char *srp_target_info(struct Scsi_Host *host)
103 {
104         return host_to_target(host)->target_name;
105 }
106
107 static int srp_target_is_topspin(struct srp_target_port *target)
108 {
109         static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
110         static const u8 cisco_oui[3]   = { 0x00, 0x1b, 0x0d };
111
112         return topspin_workarounds &&
113                 (!memcmp(&target->ioc_guid, topspin_oui, sizeof topspin_oui) ||
114                  !memcmp(&target->ioc_guid, cisco_oui, sizeof cisco_oui));
115 }
116
117 static int srp_target_is_mellanox(struct srp_target_port *target)
118 {
119         static const u8 mellanox_oui[3] = { 0x00, 0x02, 0xc9 };
120
121         return mellanox_workarounds &&
122                 !memcmp(&target->ioc_guid, mellanox_oui, sizeof mellanox_oui);
123 }
124
125 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
126                                    gfp_t gfp_mask,
127                                    enum dma_data_direction direction)
128 {
129         struct srp_iu *iu;
130
131         iu = kmalloc(sizeof *iu, gfp_mask);
132         if (!iu)
133                 goto out;
134
135         iu->buf = kzalloc(size, gfp_mask);
136         if (!iu->buf)
137                 goto out_free_iu;
138
139         iu->dma = ib_dma_map_single(host->srp_dev->dev, iu->buf, size,
140                                     direction);
141         if (ib_dma_mapping_error(host->srp_dev->dev, iu->dma))
142                 goto out_free_buf;
143
144         iu->size      = size;
145         iu->direction = direction;
146
147         return iu;
148
149 out_free_buf:
150         kfree(iu->buf);
151 out_free_iu:
152         kfree(iu);
153 out:
154         return NULL;
155 }
156
157 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
158 {
159         if (!iu)
160                 return;
161
162         ib_dma_unmap_single(host->srp_dev->dev, iu->dma, iu->size,
163                             iu->direction);
164         kfree(iu->buf);
165         kfree(iu);
166 }
167
168 static void srp_qp_event(struct ib_event *event, void *context)
169 {
170         printk(KERN_ERR PFX "QP event %d\n", event->event);
171 }
172
173 static int srp_init_qp(struct srp_target_port *target,
174                        struct ib_qp *qp)
175 {
176         struct ib_qp_attr *attr;
177         int ret;
178
179         attr = kmalloc(sizeof *attr, GFP_KERNEL);
180         if (!attr)
181                 return -ENOMEM;
182
183         ret = ib_find_pkey(target->srp_host->srp_dev->dev,
184                            target->srp_host->port,
185                            be16_to_cpu(target->path.pkey),
186                            &attr->pkey_index);
187         if (ret)
188                 goto out;
189
190         attr->qp_state        = IB_QPS_INIT;
191         attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
192                                     IB_ACCESS_REMOTE_WRITE);
193         attr->port_num        = target->srp_host->port;
194
195         ret = ib_modify_qp(qp, attr,
196                            IB_QP_STATE          |
197                            IB_QP_PKEY_INDEX     |
198                            IB_QP_ACCESS_FLAGS   |
199                            IB_QP_PORT);
200
201 out:
202         kfree(attr);
203         return ret;
204 }
205
206 static int srp_new_cm_id(struct srp_target_port *target)
207 {
208         struct ib_cm_id *new_cm_id;
209
210         new_cm_id = ib_create_cm_id(target->srp_host->srp_dev->dev,
211                                     srp_cm_handler, target);
212         if (IS_ERR(new_cm_id))
213                 return PTR_ERR(new_cm_id);
214
215         if (target->cm_id)
216                 ib_destroy_cm_id(target->cm_id);
217         target->cm_id = new_cm_id;
218
219         return 0;
220 }
221
222 static int srp_create_target_ib(struct srp_target_port *target)
223 {
224         struct ib_qp_init_attr *init_attr;
225         int ret;
226
227         init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
228         if (!init_attr)
229                 return -ENOMEM;
230
231         target->recv_cq = ib_create_cq(target->srp_host->srp_dev->dev,
232                                        srp_recv_completion, NULL, target, SRP_RQ_SIZE, 0);
233         if (IS_ERR(target->recv_cq)) {
234                 ret = PTR_ERR(target->recv_cq);
235                 goto err;
236         }
237
238         target->send_cq = ib_create_cq(target->srp_host->srp_dev->dev,
239                                        srp_send_completion, NULL, target, SRP_SQ_SIZE, 0);
240         if (IS_ERR(target->send_cq)) {
241                 ret = PTR_ERR(target->send_cq);
242                 goto err_recv_cq;
243         }
244
245         ib_req_notify_cq(target->recv_cq, IB_CQ_NEXT_COMP);
246
247         init_attr->event_handler       = srp_qp_event;
248         init_attr->cap.max_send_wr     = SRP_SQ_SIZE;
249         init_attr->cap.max_recv_wr     = SRP_RQ_SIZE;
250         init_attr->cap.max_recv_sge    = 1;
251         init_attr->cap.max_send_sge    = 1;
252         init_attr->sq_sig_type         = IB_SIGNAL_ALL_WR;
253         init_attr->qp_type             = IB_QPT_RC;
254         init_attr->send_cq             = target->send_cq;
255         init_attr->recv_cq             = target->recv_cq;
256
257         target->qp = ib_create_qp(target->srp_host->srp_dev->pd, init_attr);
258         if (IS_ERR(target->qp)) {
259                 ret = PTR_ERR(target->qp);
260                 goto err_send_cq;
261         }
262
263         ret = srp_init_qp(target, target->qp);
264         if (ret)
265                 goto err_qp;
266
267         kfree(init_attr);
268         return 0;
269
270 err_qp:
271         ib_destroy_qp(target->qp);
272
273 err_send_cq:
274         ib_destroy_cq(target->send_cq);
275
276 err_recv_cq:
277         ib_destroy_cq(target->recv_cq);
278
279 err:
280         kfree(init_attr);
281         return ret;
282 }
283
284 static void srp_free_target_ib(struct srp_target_port *target)
285 {
286         int i;
287
288         ib_destroy_qp(target->qp);
289         ib_destroy_cq(target->send_cq);
290         ib_destroy_cq(target->recv_cq);
291
292         for (i = 0; i < SRP_RQ_SIZE; ++i)
293                 srp_free_iu(target->srp_host, target->rx_ring[i]);
294         for (i = 0; i < SRP_SQ_SIZE; ++i)
295                 srp_free_iu(target->srp_host, target->tx_ring[i]);
296 }
297
298 static void srp_path_rec_completion(int status,
299                                     struct ib_sa_path_rec *pathrec,
300                                     void *target_ptr)
301 {
302         struct srp_target_port *target = target_ptr;
303
304         target->status = status;
305         if (status)
306                 shost_printk(KERN_ERR, target->scsi_host,
307                              PFX "Got failed path rec status %d\n", status);
308         else
309                 target->path = *pathrec;
310         complete(&target->done);
311 }
312
313 static int srp_lookup_path(struct srp_target_port *target)
314 {
315         target->path.numb_path = 1;
316
317         init_completion(&target->done);
318
319         target->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
320                                                    target->srp_host->srp_dev->dev,
321                                                    target->srp_host->port,
322                                                    &target->path,
323                                                    IB_SA_PATH_REC_SERVICE_ID    |
324                                                    IB_SA_PATH_REC_DGID          |
325                                                    IB_SA_PATH_REC_SGID          |
326                                                    IB_SA_PATH_REC_NUMB_PATH     |
327                                                    IB_SA_PATH_REC_PKEY,
328                                                    SRP_PATH_REC_TIMEOUT_MS,
329                                                    GFP_KERNEL,
330                                                    srp_path_rec_completion,
331                                                    target, &target->path_query);
332         if (target->path_query_id < 0)
333                 return target->path_query_id;
334
335         wait_for_completion(&target->done);
336
337         if (target->status < 0)
338                 shost_printk(KERN_WARNING, target->scsi_host,
339                              PFX "Path record query failed\n");
340
341         return target->status;
342 }
343
344 static int srp_send_req(struct srp_target_port *target)
345 {
346         struct {
347                 struct ib_cm_req_param param;
348                 struct srp_login_req   priv;
349         } *req = NULL;
350         int status;
351
352         req = kzalloc(sizeof *req, GFP_KERNEL);
353         if (!req)
354                 return -ENOMEM;
355
356         req->param.primary_path               = &target->path;
357         req->param.alternate_path             = NULL;
358         req->param.service_id                 = target->service_id;
359         req->param.qp_num                     = target->qp->qp_num;
360         req->param.qp_type                    = target->qp->qp_type;
361         req->param.private_data               = &req->priv;
362         req->param.private_data_len           = sizeof req->priv;
363         req->param.flow_control               = 1;
364
365         get_random_bytes(&req->param.starting_psn, 4);
366         req->param.starting_psn              &= 0xffffff;
367
368         /*
369          * Pick some arbitrary defaults here; we could make these
370          * module parameters if anyone cared about setting them.
371          */
372         req->param.responder_resources        = 4;
373         req->param.remote_cm_response_timeout = 20;
374         req->param.local_cm_response_timeout  = 20;
375         req->param.retry_count                = 7;
376         req->param.rnr_retry_count            = 7;
377         req->param.max_cm_retries             = 15;
378
379         req->priv.opcode        = SRP_LOGIN_REQ;
380         req->priv.tag           = 0;
381         req->priv.req_it_iu_len = cpu_to_be32(srp_max_iu_len);
382         req->priv.req_buf_fmt   = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
383                                               SRP_BUF_FORMAT_INDIRECT);
384         /*
385          * In the published SRP specification (draft rev. 16a), the
386          * port identifier format is 8 bytes of ID extension followed
387          * by 8 bytes of GUID.  Older drafts put the two halves in the
388          * opposite order, so that the GUID comes first.
389          *
390          * Targets conforming to these obsolete drafts can be
391          * recognized by the I/O Class they report.
392          */
393         if (target->io_class == SRP_REV10_IB_IO_CLASS) {
394                 memcpy(req->priv.initiator_port_id,
395                        &target->path.sgid.global.interface_id, 8);
396                 memcpy(req->priv.initiator_port_id + 8,
397                        &target->initiator_ext, 8);
398                 memcpy(req->priv.target_port_id,     &target->ioc_guid, 8);
399                 memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
400         } else {
401                 memcpy(req->priv.initiator_port_id,
402                        &target->initiator_ext, 8);
403                 memcpy(req->priv.initiator_port_id + 8,
404                        &target->path.sgid.global.interface_id, 8);
405                 memcpy(req->priv.target_port_id,     &target->id_ext, 8);
406                 memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
407         }
408
409         /*
410          * Topspin/Cisco SRP targets will reject our login unless we
411          * zero out the first 8 bytes of our initiator port ID and set
412          * the second 8 bytes to the local node GUID.
413          */
414         if (srp_target_is_topspin(target)) {
415                 shost_printk(KERN_DEBUG, target->scsi_host,
416                              PFX "Topspin/Cisco initiator port ID workaround "
417                              "activated for target GUID %016llx\n",
418                              (unsigned long long) be64_to_cpu(target->ioc_guid));
419                 memset(req->priv.initiator_port_id, 0, 8);
420                 memcpy(req->priv.initiator_port_id + 8,
421                        &target->srp_host->srp_dev->dev->node_guid, 8);
422         }
423
424         status = ib_send_cm_req(target->cm_id, &req->param);
425
426         kfree(req);
427
428         return status;
429 }
430
431 static void srp_disconnect_target(struct srp_target_port *target)
432 {
433         /* XXX should send SRP_I_LOGOUT request */
434
435         init_completion(&target->done);
436         if (ib_send_cm_dreq(target->cm_id, NULL, 0)) {
437                 shost_printk(KERN_DEBUG, target->scsi_host,
438                              PFX "Sending CM DREQ failed\n");
439                 return;
440         }
441         wait_for_completion(&target->done);
442 }
443
444 static bool srp_change_state(struct srp_target_port *target,
445                             enum srp_target_state old,
446                             enum srp_target_state new)
447 {
448         bool changed = false;
449
450         spin_lock_irq(&target->lock);
451         if (target->state == old) {
452                 target->state = new;
453                 changed = true;
454         }
455         spin_unlock_irq(&target->lock);
456         return changed;
457 }
458
459 static void srp_remove_work(struct work_struct *work)
460 {
461         struct srp_target_port *target =
462                 container_of(work, struct srp_target_port, work);
463
464         if (!srp_change_state(target, SRP_TARGET_DEAD, SRP_TARGET_REMOVED))
465                 return;
466
467         spin_lock(&target->srp_host->target_lock);
468         list_del(&target->list);
469         spin_unlock(&target->srp_host->target_lock);
470
471         srp_remove_host(target->scsi_host);
472         scsi_remove_host(target->scsi_host);
473         ib_destroy_cm_id(target->cm_id);
474         srp_free_target_ib(target);
475         scsi_host_put(target->scsi_host);
476 }
477
478 static int srp_connect_target(struct srp_target_port *target)
479 {
480         int retries = 3;
481         int ret;
482
483         ret = srp_lookup_path(target);
484         if (ret)
485                 return ret;
486
487         while (1) {
488                 init_completion(&target->done);
489                 ret = srp_send_req(target);
490                 if (ret)
491                         return ret;
492                 wait_for_completion(&target->done);
493
494                 /*
495                  * The CM event handling code will set status to
496                  * SRP_PORT_REDIRECT if we get a port redirect REJ
497                  * back, or SRP_DLID_REDIRECT if we get a lid/qp
498                  * redirect REJ back.
499                  */
500                 switch (target->status) {
501                 case 0:
502                         return 0;
503
504                 case SRP_PORT_REDIRECT:
505                         ret = srp_lookup_path(target);
506                         if (ret)
507                                 return ret;
508                         break;
509
510                 case SRP_DLID_REDIRECT:
511                         break;
512
513                 case SRP_STALE_CONN:
514                         /* Our current CM id was stale, and is now in timewait.
515                          * Try to reconnect with a new one.
516                          */
517                         if (!retries-- || srp_new_cm_id(target)) {
518                                 shost_printk(KERN_ERR, target->scsi_host, PFX
519                                              "giving up on stale connection\n");
520                                 target->status = -ECONNRESET;
521                                 return target->status;
522                         }
523
524                         shost_printk(KERN_ERR, target->scsi_host, PFX
525                                      "retrying stale connection\n");
526                         break;
527
528                 default:
529                         return target->status;
530                 }
531         }
532 }
533
534 static void srp_unmap_data(struct scsi_cmnd *scmnd,
535                            struct srp_target_port *target,
536                            struct srp_request *req)
537 {
538         if (!scsi_sglist(scmnd) ||
539             (scmnd->sc_data_direction != DMA_TO_DEVICE &&
540              scmnd->sc_data_direction != DMA_FROM_DEVICE))
541                 return;
542
543         if (req->fmr) {
544                 ib_fmr_pool_unmap(req->fmr);
545                 req->fmr = NULL;
546         }
547
548         ib_dma_unmap_sg(target->srp_host->srp_dev->dev, scsi_sglist(scmnd),
549                         scsi_sg_count(scmnd), scmnd->sc_data_direction);
550 }
551
552 static void srp_remove_req(struct srp_target_port *target,
553                            struct srp_request *req, s32 req_lim_delta)
554 {
555         unsigned long flags;
556
557         srp_unmap_data(req->scmnd, target, req);
558         spin_lock_irqsave(&target->lock, flags);
559         target->req_lim += req_lim_delta;
560         req->scmnd = NULL;
561         list_add_tail(&req->list, &target->free_reqs);
562         spin_unlock_irqrestore(&target->lock, flags);
563 }
564
565 static void srp_reset_req(struct srp_target_port *target, struct srp_request *req)
566 {
567         req->scmnd->result = DID_RESET << 16;
568         req->scmnd->scsi_done(req->scmnd);
569         srp_remove_req(target, req, 0);
570 }
571
572 static int srp_reconnect_target(struct srp_target_port *target)
573 {
574         struct ib_qp_attr qp_attr;
575         struct ib_wc wc;
576         int i, ret;
577
578         if (!srp_change_state(target, SRP_TARGET_LIVE, SRP_TARGET_CONNECTING))
579                 return -EAGAIN;
580
581         srp_disconnect_target(target);
582         /*
583          * Now get a new local CM ID so that we avoid confusing the
584          * target in case things are really fouled up.
585          */
586         ret = srp_new_cm_id(target);
587         if (ret)
588                 goto err;
589
590         qp_attr.qp_state = IB_QPS_RESET;
591         ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
592         if (ret)
593                 goto err;
594
595         ret = srp_init_qp(target, target->qp);
596         if (ret)
597                 goto err;
598
599         while (ib_poll_cq(target->recv_cq, 1, &wc) > 0)
600                 ; /* nothing */
601         while (ib_poll_cq(target->send_cq, 1, &wc) > 0)
602                 ; /* nothing */
603
604         for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
605                 struct srp_request *req = &target->req_ring[i];
606                 if (req->scmnd)
607                         srp_reset_req(target, req);
608         }
609
610         INIT_LIST_HEAD(&target->free_tx);
611         for (i = 0; i < SRP_SQ_SIZE; ++i)
612                 list_add(&target->tx_ring[i]->list, &target->free_tx);
613
614         target->qp_in_error = 0;
615         ret = srp_connect_target(target);
616         if (ret)
617                 goto err;
618
619         if (!srp_change_state(target, SRP_TARGET_CONNECTING, SRP_TARGET_LIVE))
620                 ret = -EAGAIN;
621
622         return ret;
623
624 err:
625         shost_printk(KERN_ERR, target->scsi_host,
626                      PFX "reconnect failed (%d), removing target port.\n", ret);
627
628         /*
629          * We couldn't reconnect, so kill our target port off.
630          * However, we have to defer the real removal because we
631          * are in the context of the SCSI error handler now, which
632          * will deadlock if we call scsi_remove_host().
633          *
634          * Schedule our work inside the lock to avoid a race with
635          * the flush_scheduled_work() in srp_remove_one().
636          */
637         spin_lock_irq(&target->lock);
638         if (target->state == SRP_TARGET_CONNECTING) {
639                 target->state = SRP_TARGET_DEAD;
640                 INIT_WORK(&target->work, srp_remove_work);
641                 schedule_work(&target->work);
642         }
643         spin_unlock_irq(&target->lock);
644
645         return ret;
646 }
647
648 static int srp_map_fmr(struct srp_target_port *target, struct scatterlist *scat,
649                        int sg_cnt, struct srp_request *req,
650                        struct srp_direct_buf *buf)
651 {
652         u64 io_addr = 0;
653         u64 *dma_pages;
654         u32 len;
655         int page_cnt;
656         int i, j;
657         int ret;
658         struct srp_device *dev = target->srp_host->srp_dev;
659         struct ib_device *ibdev = dev->dev;
660         struct scatterlist *sg;
661
662         if (!dev->fmr_pool)
663                 return -ENODEV;
664
665         if (srp_target_is_mellanox(target) &&
666             (ib_sg_dma_address(ibdev, &scat[0]) & ~dev->fmr_page_mask))
667                 return -EINVAL;
668
669         len = page_cnt = 0;
670         scsi_for_each_sg(req->scmnd, sg, sg_cnt, i) {
671                 unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
672
673                 if (ib_sg_dma_address(ibdev, sg) & ~dev->fmr_page_mask) {
674                         if (i > 0)
675                                 return -EINVAL;
676                         else
677                                 ++page_cnt;
678                 }
679                 if ((ib_sg_dma_address(ibdev, sg) + dma_len) &
680                     ~dev->fmr_page_mask) {
681                         if (i < sg_cnt - 1)
682                                 return -EINVAL;
683                         else
684                                 ++page_cnt;
685                 }
686
687                 len += dma_len;
688         }
689
690         page_cnt += len >> dev->fmr_page_shift;
691         if (page_cnt > SRP_FMR_SIZE)
692                 return -ENOMEM;
693
694         dma_pages = kmalloc(sizeof (u64) * page_cnt, GFP_ATOMIC);
695         if (!dma_pages)
696                 return -ENOMEM;
697
698         page_cnt = 0;
699         scsi_for_each_sg(req->scmnd, sg, sg_cnt, i) {
700                 unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
701
702                 for (j = 0; j < dma_len; j += dev->fmr_page_size)
703                         dma_pages[page_cnt++] =
704                                 (ib_sg_dma_address(ibdev, sg) &
705                                  dev->fmr_page_mask) + j;
706         }
707
708         req->fmr = ib_fmr_pool_map_phys(dev->fmr_pool,
709                                         dma_pages, page_cnt, io_addr);
710         if (IS_ERR(req->fmr)) {
711                 ret = PTR_ERR(req->fmr);
712                 req->fmr = NULL;
713                 goto out;
714         }
715
716         buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, &scat[0]) &
717                                ~dev->fmr_page_mask);
718         buf->key = cpu_to_be32(req->fmr->fmr->rkey);
719         buf->len = cpu_to_be32(len);
720
721         ret = 0;
722
723 out:
724         kfree(dma_pages);
725
726         return ret;
727 }
728
729 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
730                         struct srp_request *req)
731 {
732         struct scatterlist *scat;
733         struct srp_cmd *cmd = req->cmd->buf;
734         int len, nents, count;
735         u8 fmt = SRP_DATA_DESC_DIRECT;
736         struct srp_device *dev;
737         struct ib_device *ibdev;
738
739         if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
740                 return sizeof (struct srp_cmd);
741
742         if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
743             scmnd->sc_data_direction != DMA_TO_DEVICE) {
744                 shost_printk(KERN_WARNING, target->scsi_host,
745                              PFX "Unhandled data direction %d\n",
746                              scmnd->sc_data_direction);
747                 return -EINVAL;
748         }
749
750         nents = scsi_sg_count(scmnd);
751         scat  = scsi_sglist(scmnd);
752
753         dev = target->srp_host->srp_dev;
754         ibdev = dev->dev;
755
756         count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
757
758         fmt = SRP_DATA_DESC_DIRECT;
759         len = sizeof (struct srp_cmd) + sizeof (struct srp_direct_buf);
760
761         if (count == 1) {
762                 /*
763                  * The midlayer only generated a single gather/scatter
764                  * entry, or DMA mapping coalesced everything to a
765                  * single entry.  So a direct descriptor along with
766                  * the DMA MR suffices.
767                  */
768                 struct srp_direct_buf *buf = (void *) cmd->add_data;
769
770                 buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
771                 buf->key = cpu_to_be32(target->rkey);
772                 buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
773         } else if (srp_map_fmr(target, scat, count, req,
774                                (void *) cmd->add_data)) {
775                 /*
776                  * FMR mapping failed, and the scatterlist has more
777                  * than one entry.  Generate an indirect memory
778                  * descriptor.
779                  */
780                 struct srp_indirect_buf *buf = (void *) cmd->add_data;
781                 struct scatterlist *sg;
782                 u32 datalen = 0;
783                 int i;
784
785                 fmt = SRP_DATA_DESC_INDIRECT;
786                 len = sizeof (struct srp_cmd) +
787                         sizeof (struct srp_indirect_buf) +
788                         count * sizeof (struct srp_direct_buf);
789
790                 scsi_for_each_sg(scmnd, sg, count, i) {
791                         unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
792
793                         buf->desc_list[i].va  =
794                                 cpu_to_be64(ib_sg_dma_address(ibdev, sg));
795                         buf->desc_list[i].key =
796                                 cpu_to_be32(target->rkey);
797                         buf->desc_list[i].len = cpu_to_be32(dma_len);
798                         datalen += dma_len;
799                 }
800
801                 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
802                         cmd->data_out_desc_cnt = count;
803                 else
804                         cmd->data_in_desc_cnt = count;
805
806                 buf->table_desc.va  =
807                         cpu_to_be64(req->cmd->dma + sizeof *cmd + sizeof *buf);
808                 buf->table_desc.key =
809                         cpu_to_be32(target->rkey);
810                 buf->table_desc.len =
811                         cpu_to_be32(count * sizeof (struct srp_direct_buf));
812
813                 buf->len = cpu_to_be32(datalen);
814         }
815
816         if (scmnd->sc_data_direction == DMA_TO_DEVICE)
817                 cmd->buf_fmt = fmt << 4;
818         else
819                 cmd->buf_fmt = fmt;
820
821         return len;
822 }
823
824 /*
825  * Return an IU and possible credit to the free pool
826  */
827 static void srp_put_tx_iu(struct srp_target_port *target, struct srp_iu *iu,
828                           enum srp_iu_type iu_type)
829 {
830         unsigned long flags;
831
832         spin_lock_irqsave(&target->lock, flags);
833         list_add(&iu->list, &target->free_tx);
834         if (iu_type != SRP_IU_RSP)
835                 ++target->req_lim;
836         spin_unlock_irqrestore(&target->lock, flags);
837 }
838
839 /*
840  * Must be called with target->lock held to protect req_lim and free_tx.
841  * If IU is not sent, it must be returned using srp_put_tx_iu().
842  *
843  * Note:
844  * An upper limit for the number of allocated information units for each
845  * request type is:
846  * - SRP_IU_CMD: SRP_CMD_SQ_SIZE, since the SCSI mid-layer never queues
847  *   more than Scsi_Host.can_queue requests.
848  * - SRP_IU_TSK_MGMT: SRP_TSK_MGMT_SQ_SIZE.
849  * - SRP_IU_RSP: 1, since a conforming SRP target never sends more than
850  *   one unanswered SRP request to an initiator.
851  */
852 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target,
853                                       enum srp_iu_type iu_type)
854 {
855         s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
856         struct srp_iu *iu;
857
858         srp_send_completion(target->send_cq, target);
859
860         if (list_empty(&target->free_tx))
861                 return NULL;
862
863         /* Initiator responses to target requests do not consume credits */
864         if (iu_type != SRP_IU_RSP) {
865                 if (target->req_lim <= rsv) {
866                         ++target->zero_req_lim;
867                         return NULL;
868                 }
869
870                 --target->req_lim;
871         }
872
873         iu = list_first_entry(&target->free_tx, struct srp_iu, list);
874         list_del(&iu->list);
875         return iu;
876 }
877
878 static int srp_post_send(struct srp_target_port *target,
879                          struct srp_iu *iu, int len)
880 {
881         struct ib_sge list;
882         struct ib_send_wr wr, *bad_wr;
883
884         list.addr   = iu->dma;
885         list.length = len;
886         list.lkey   = target->lkey;
887
888         wr.next       = NULL;
889         wr.wr_id      = (uintptr_t) iu;
890         wr.sg_list    = &list;
891         wr.num_sge    = 1;
892         wr.opcode     = IB_WR_SEND;
893         wr.send_flags = IB_SEND_SIGNALED;
894
895         return ib_post_send(target->qp, &wr, &bad_wr);
896 }
897
898 static int srp_post_recv(struct srp_target_port *target, struct srp_iu *iu)
899 {
900         struct ib_recv_wr wr, *bad_wr;
901         struct ib_sge list;
902
903         list.addr   = iu->dma;
904         list.length = iu->size;
905         list.lkey   = target->lkey;
906
907         wr.next     = NULL;
908         wr.wr_id    = (uintptr_t) iu;
909         wr.sg_list  = &list;
910         wr.num_sge  = 1;
911
912         return ib_post_recv(target->qp, &wr, &bad_wr);
913 }
914
915 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
916 {
917         struct srp_request *req;
918         struct scsi_cmnd *scmnd;
919         unsigned long flags;
920
921         if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
922                 spin_lock_irqsave(&target->lock, flags);
923                 target->req_lim += be32_to_cpu(rsp->req_lim_delta);
924                 spin_unlock_irqrestore(&target->lock, flags);
925
926                 target->tsk_mgmt_status = -1;
927                 if (be32_to_cpu(rsp->resp_data_len) >= 4)
928                         target->tsk_mgmt_status = rsp->data[3];
929                 complete(&target->tsk_mgmt_done);
930         } else {
931                 req = &target->req_ring[rsp->tag];
932                 scmnd = req->scmnd;
933                 if (!scmnd)
934                         shost_printk(KERN_ERR, target->scsi_host,
935                                      "Null scmnd for RSP w/tag %016llx\n",
936                                      (unsigned long long) rsp->tag);
937                 scmnd->result = rsp->status;
938
939                 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
940                         memcpy(scmnd->sense_buffer, rsp->data +
941                                be32_to_cpu(rsp->resp_data_len),
942                                min_t(int, be32_to_cpu(rsp->sense_data_len),
943                                      SCSI_SENSE_BUFFERSIZE));
944                 }
945
946                 if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
947                         scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
948                 else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
949                         scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
950
951                 srp_remove_req(target, req, be32_to_cpu(rsp->req_lim_delta));
952                 scmnd->host_scribble = NULL;
953                 scmnd->scsi_done(scmnd);
954         }
955 }
956
957 static int srp_response_common(struct srp_target_port *target, s32 req_delta,
958                                void *rsp, int len)
959 {
960         struct ib_device *dev = target->srp_host->srp_dev->dev;
961         unsigned long flags;
962         struct srp_iu *iu;
963         int err;
964
965         spin_lock_irqsave(&target->lock, flags);
966         target->req_lim += req_delta;
967         iu = __srp_get_tx_iu(target, SRP_IU_RSP);
968         spin_unlock_irqrestore(&target->lock, flags);
969
970         if (!iu) {
971                 shost_printk(KERN_ERR, target->scsi_host, PFX
972                              "no IU available to send response\n");
973                 return 1;
974         }
975
976         ib_dma_sync_single_for_cpu(dev, iu->dma, len, DMA_TO_DEVICE);
977         memcpy(iu->buf, rsp, len);
978         ib_dma_sync_single_for_device(dev, iu->dma, len, DMA_TO_DEVICE);
979
980         err = srp_post_send(target, iu, len);
981         if (err) {
982                 shost_printk(KERN_ERR, target->scsi_host, PFX
983                              "unable to post response: %d\n", err);
984                 srp_put_tx_iu(target, iu, SRP_IU_RSP);
985         }
986
987         return err;
988 }
989
990 static void srp_process_cred_req(struct srp_target_port *target,
991                                  struct srp_cred_req *req)
992 {
993         struct srp_cred_rsp rsp = {
994                 .opcode = SRP_CRED_RSP,
995                 .tag = req->tag,
996         };
997         s32 delta = be32_to_cpu(req->req_lim_delta);
998
999         if (srp_response_common(target, delta, &rsp, sizeof rsp))
1000                 shost_printk(KERN_ERR, target->scsi_host, PFX
1001                              "problems processing SRP_CRED_REQ\n");
1002 }
1003
1004 static void srp_process_aer_req(struct srp_target_port *target,
1005                                 struct srp_aer_req *req)
1006 {
1007         struct srp_aer_rsp rsp = {
1008                 .opcode = SRP_AER_RSP,
1009                 .tag = req->tag,
1010         };
1011         s32 delta = be32_to_cpu(req->req_lim_delta);
1012
1013         shost_printk(KERN_ERR, target->scsi_host, PFX
1014                      "ignoring AER for LUN %llu\n", be64_to_cpu(req->lun));
1015
1016         if (srp_response_common(target, delta, &rsp, sizeof rsp))
1017                 shost_printk(KERN_ERR, target->scsi_host, PFX
1018                              "problems processing SRP_AER_REQ\n");
1019 }
1020
1021 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
1022 {
1023         struct ib_device *dev = target->srp_host->srp_dev->dev;
1024         struct srp_iu *iu = (struct srp_iu *) wc->wr_id;
1025         int res;
1026         u8 opcode;
1027
1028         ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_ti_iu_len,
1029                                    DMA_FROM_DEVICE);
1030
1031         opcode = *(u8 *) iu->buf;
1032
1033         if (0) {
1034                 shost_printk(KERN_ERR, target->scsi_host,
1035                              PFX "recv completion, opcode 0x%02x\n", opcode);
1036                 print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
1037                                iu->buf, wc->byte_len, true);
1038         }
1039
1040         switch (opcode) {
1041         case SRP_RSP:
1042                 srp_process_rsp(target, iu->buf);
1043                 break;
1044
1045         case SRP_CRED_REQ:
1046                 srp_process_cred_req(target, iu->buf);
1047                 break;
1048
1049         case SRP_AER_REQ:
1050                 srp_process_aer_req(target, iu->buf);
1051                 break;
1052
1053         case SRP_T_LOGOUT:
1054                 /* XXX Handle target logout */
1055                 shost_printk(KERN_WARNING, target->scsi_host,
1056                              PFX "Got target logout request\n");
1057                 break;
1058
1059         default:
1060                 shost_printk(KERN_WARNING, target->scsi_host,
1061                              PFX "Unhandled SRP opcode 0x%02x\n", opcode);
1062                 break;
1063         }
1064
1065         ib_dma_sync_single_for_device(dev, iu->dma, target->max_ti_iu_len,
1066                                       DMA_FROM_DEVICE);
1067
1068         res = srp_post_recv(target, iu);
1069         if (res != 0)
1070                 shost_printk(KERN_ERR, target->scsi_host,
1071                              PFX "Recv failed with error code %d\n", res);
1072 }
1073
1074 static void srp_recv_completion(struct ib_cq *cq, void *target_ptr)
1075 {
1076         struct srp_target_port *target = target_ptr;
1077         struct ib_wc wc;
1078
1079         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
1080         while (ib_poll_cq(cq, 1, &wc) > 0) {
1081                 if (wc.status) {
1082                         shost_printk(KERN_ERR, target->scsi_host,
1083                                      PFX "failed receive status %d\n",
1084                                      wc.status);
1085                         target->qp_in_error = 1;
1086                         break;
1087                 }
1088
1089                 srp_handle_recv(target, &wc);
1090         }
1091 }
1092
1093 static void srp_send_completion(struct ib_cq *cq, void *target_ptr)
1094 {
1095         struct srp_target_port *target = target_ptr;
1096         struct ib_wc wc;
1097         struct srp_iu *iu;
1098
1099         while (ib_poll_cq(cq, 1, &wc) > 0) {
1100                 if (wc.status) {
1101                         shost_printk(KERN_ERR, target->scsi_host,
1102                                      PFX "failed send status %d\n",
1103                                      wc.status);
1104                         target->qp_in_error = 1;
1105                         break;
1106                 }
1107
1108                 iu = (struct srp_iu *) wc.wr_id;
1109                 list_add(&iu->list, &target->free_tx);
1110         }
1111 }
1112
1113 static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
1114 {
1115         struct srp_target_port *target = host_to_target(shost);
1116         struct srp_request *req;
1117         struct srp_iu *iu;
1118         struct srp_cmd *cmd;
1119         struct ib_device *dev;
1120         unsigned long flags;
1121         int len;
1122
1123         if (target->state == SRP_TARGET_CONNECTING)
1124                 goto err;
1125
1126         if (target->state == SRP_TARGET_DEAD ||
1127             target->state == SRP_TARGET_REMOVED) {
1128                 scmnd->result = DID_BAD_TARGET << 16;
1129                 scmnd->scsi_done(scmnd);
1130                 return 0;
1131         }
1132
1133         spin_lock_irqsave(&target->lock, flags);
1134         iu = __srp_get_tx_iu(target, SRP_IU_CMD);
1135         if (iu) {
1136                 req = list_first_entry(&target->free_reqs, struct srp_request,
1137                                       list);
1138                 list_del(&req->list);
1139         }
1140         spin_unlock_irqrestore(&target->lock, flags);
1141
1142         if (!iu)
1143                 goto err;
1144
1145         dev = target->srp_host->srp_dev->dev;
1146         ib_dma_sync_single_for_cpu(dev, iu->dma, srp_max_iu_len,
1147                                    DMA_TO_DEVICE);
1148
1149         scmnd->result        = 0;
1150         scmnd->host_scribble = (void *) req;
1151
1152         cmd = iu->buf;
1153         memset(cmd, 0, sizeof *cmd);
1154
1155         cmd->opcode = SRP_CMD;
1156         cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
1157         cmd->tag    = req->index;
1158         memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
1159
1160         req->scmnd    = scmnd;
1161         req->cmd      = iu;
1162
1163         len = srp_map_data(scmnd, target, req);
1164         if (len < 0) {
1165                 shost_printk(KERN_ERR, target->scsi_host,
1166                              PFX "Failed to map data\n");
1167                 goto err_iu;
1168         }
1169
1170         ib_dma_sync_single_for_device(dev, iu->dma, srp_max_iu_len,
1171                                       DMA_TO_DEVICE);
1172
1173         if (srp_post_send(target, iu, len)) {
1174                 shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
1175                 goto err_unmap;
1176         }
1177
1178         return 0;
1179
1180 err_unmap:
1181         srp_unmap_data(scmnd, target, req);
1182
1183 err_iu:
1184         srp_put_tx_iu(target, iu, SRP_IU_CMD);
1185
1186         spin_lock_irqsave(&target->lock, flags);
1187         list_add(&req->list, &target->free_reqs);
1188         spin_unlock_irqrestore(&target->lock, flags);
1189
1190 err:
1191         return SCSI_MLQUEUE_HOST_BUSY;
1192 }
1193
1194 static int srp_alloc_iu_bufs(struct srp_target_port *target)
1195 {
1196         int i;
1197
1198         for (i = 0; i < SRP_RQ_SIZE; ++i) {
1199                 target->rx_ring[i] = srp_alloc_iu(target->srp_host,
1200                                                   target->max_ti_iu_len,
1201                                                   GFP_KERNEL, DMA_FROM_DEVICE);
1202                 if (!target->rx_ring[i])
1203                         goto err;
1204         }
1205
1206         for (i = 0; i < SRP_SQ_SIZE; ++i) {
1207                 target->tx_ring[i] = srp_alloc_iu(target->srp_host,
1208                                                   srp_max_iu_len,
1209                                                   GFP_KERNEL, DMA_TO_DEVICE);
1210                 if (!target->tx_ring[i])
1211                         goto err;
1212
1213                 list_add(&target->tx_ring[i]->list, &target->free_tx);
1214         }
1215
1216         return 0;
1217
1218 err:
1219         for (i = 0; i < SRP_RQ_SIZE; ++i) {
1220                 srp_free_iu(target->srp_host, target->rx_ring[i]);
1221                 target->rx_ring[i] = NULL;
1222         }
1223
1224         for (i = 0; i < SRP_SQ_SIZE; ++i) {
1225                 srp_free_iu(target->srp_host, target->tx_ring[i]);
1226                 target->tx_ring[i] = NULL;
1227         }
1228
1229         return -ENOMEM;
1230 }
1231
1232 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
1233                                struct ib_cm_event *event,
1234                                struct srp_target_port *target)
1235 {
1236         struct Scsi_Host *shost = target->scsi_host;
1237         struct ib_class_port_info *cpi;
1238         int opcode;
1239
1240         switch (event->param.rej_rcvd.reason) {
1241         case IB_CM_REJ_PORT_CM_REDIRECT:
1242                 cpi = event->param.rej_rcvd.ari;
1243                 target->path.dlid = cpi->redirect_lid;
1244                 target->path.pkey = cpi->redirect_pkey;
1245                 cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
1246                 memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
1247
1248                 target->status = target->path.dlid ?
1249                         SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
1250                 break;
1251
1252         case IB_CM_REJ_PORT_REDIRECT:
1253                 if (srp_target_is_topspin(target)) {
1254                         /*
1255                          * Topspin/Cisco SRP gateways incorrectly send
1256                          * reject reason code 25 when they mean 24
1257                          * (port redirect).
1258                          */
1259                         memcpy(target->path.dgid.raw,
1260                                event->param.rej_rcvd.ari, 16);
1261
1262                         shost_printk(KERN_DEBUG, shost,
1263                                      PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
1264                                      (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
1265                                      (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
1266
1267                         target->status = SRP_PORT_REDIRECT;
1268                 } else {
1269                         shost_printk(KERN_WARNING, shost,
1270                                      "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
1271                         target->status = -ECONNRESET;
1272                 }
1273                 break;
1274
1275         case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
1276                 shost_printk(KERN_WARNING, shost,
1277                             "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
1278                 target->status = -ECONNRESET;
1279                 break;
1280
1281         case IB_CM_REJ_CONSUMER_DEFINED:
1282                 opcode = *(u8 *) event->private_data;
1283                 if (opcode == SRP_LOGIN_REJ) {
1284                         struct srp_login_rej *rej = event->private_data;
1285                         u32 reason = be32_to_cpu(rej->reason);
1286
1287                         if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
1288                                 shost_printk(KERN_WARNING, shost,
1289                                              PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
1290                         else
1291                                 shost_printk(KERN_WARNING, shost,
1292                                             PFX "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
1293                 } else
1294                         shost_printk(KERN_WARNING, shost,
1295                                      "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
1296                                      " opcode 0x%02x\n", opcode);
1297                 target->status = -ECONNRESET;
1298                 break;
1299
1300         case IB_CM_REJ_STALE_CONN:
1301                 shost_printk(KERN_WARNING, shost, "  REJ reason: stale connection\n");
1302                 target->status = SRP_STALE_CONN;
1303                 break;
1304
1305         default:
1306                 shost_printk(KERN_WARNING, shost, "  REJ reason 0x%x\n",
1307                              event->param.rej_rcvd.reason);
1308                 target->status = -ECONNRESET;
1309         }
1310 }
1311
1312 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
1313 {
1314         struct srp_target_port *target = cm_id->context;
1315         struct ib_qp_attr *qp_attr = NULL;
1316         int attr_mask = 0;
1317         int comp = 0;
1318         int opcode = 0;
1319         int i;
1320
1321         switch (event->event) {
1322         case IB_CM_REQ_ERROR:
1323                 shost_printk(KERN_DEBUG, target->scsi_host,
1324                              PFX "Sending CM REQ failed\n");
1325                 comp = 1;
1326                 target->status = -ECONNRESET;
1327                 break;
1328
1329         case IB_CM_REP_RECEIVED:
1330                 comp = 1;
1331                 opcode = *(u8 *) event->private_data;
1332
1333                 if (opcode == SRP_LOGIN_RSP) {
1334                         struct srp_login_rsp *rsp = event->private_data;
1335
1336                         target->max_ti_iu_len = be32_to_cpu(rsp->max_ti_iu_len);
1337                         target->req_lim       = be32_to_cpu(rsp->req_lim_delta);
1338
1339                         /*
1340                          * Reserve credits for task management so we don't
1341                          * bounce requests back to the SCSI mid-layer.
1342                          */
1343                         target->scsi_host->can_queue
1344                                 = min(target->req_lim - SRP_TSK_MGMT_SQ_SIZE,
1345                                       target->scsi_host->can_queue);
1346                 } else {
1347                         shost_printk(KERN_WARNING, target->scsi_host,
1348                                     PFX "Unhandled RSP opcode %#x\n", opcode);
1349                         target->status = -ECONNRESET;
1350                         break;
1351                 }
1352
1353                 if (!target->rx_ring[0]) {
1354                         target->status = srp_alloc_iu_bufs(target);
1355                         if (target->status)
1356                                 break;
1357                 }
1358
1359                 qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
1360                 if (!qp_attr) {
1361                         target->status = -ENOMEM;
1362                         break;
1363                 }
1364
1365                 qp_attr->qp_state = IB_QPS_RTR;
1366                 target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1367                 if (target->status)
1368                         break;
1369
1370                 target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1371                 if (target->status)
1372                         break;
1373
1374                 for (i = 0; i < SRP_RQ_SIZE; i++) {
1375                         struct srp_iu *iu = target->rx_ring[i];
1376                         target->status = srp_post_recv(target, iu);
1377                         if (target->status)
1378                                 break;
1379                 }
1380                 if (target->status)
1381                         break;
1382
1383                 qp_attr->qp_state = IB_QPS_RTS;
1384                 target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1385                 if (target->status)
1386                         break;
1387
1388                 target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1389                 if (target->status)
1390                         break;
1391
1392                 target->status = ib_send_cm_rtu(cm_id, NULL, 0);
1393                 if (target->status)
1394                         break;
1395
1396                 break;
1397
1398         case IB_CM_REJ_RECEIVED:
1399                 shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
1400                 comp = 1;
1401
1402                 srp_cm_rej_handler(cm_id, event, target);
1403                 break;
1404
1405         case IB_CM_DREQ_RECEIVED:
1406                 shost_printk(KERN_WARNING, target->scsi_host,
1407                              PFX "DREQ received - connection closed\n");
1408                 if (ib_send_cm_drep(cm_id, NULL, 0))
1409                         shost_printk(KERN_ERR, target->scsi_host,
1410                                      PFX "Sending CM DREP failed\n");
1411                 break;
1412
1413         case IB_CM_TIMEWAIT_EXIT:
1414                 shost_printk(KERN_ERR, target->scsi_host,
1415                              PFX "connection closed\n");
1416
1417                 comp = 1;
1418                 target->status = 0;
1419                 break;
1420
1421         case IB_CM_MRA_RECEIVED:
1422         case IB_CM_DREQ_ERROR:
1423         case IB_CM_DREP_RECEIVED:
1424                 break;
1425
1426         default:
1427                 shost_printk(KERN_WARNING, target->scsi_host,
1428                              PFX "Unhandled CM event %d\n", event->event);
1429                 break;
1430         }
1431
1432         if (comp)
1433                 complete(&target->done);
1434
1435         kfree(qp_attr);
1436
1437         return 0;
1438 }
1439
1440 static int srp_send_tsk_mgmt(struct srp_target_port *target,
1441                              u64 req_tag, unsigned int lun, u8 func)
1442 {
1443         struct ib_device *dev = target->srp_host->srp_dev->dev;
1444         struct srp_iu *iu;
1445         struct srp_tsk_mgmt *tsk_mgmt;
1446
1447         if (target->state == SRP_TARGET_DEAD ||
1448             target->state == SRP_TARGET_REMOVED)
1449                 return -1;
1450
1451         init_completion(&target->tsk_mgmt_done);
1452
1453         spin_lock_irq(&target->lock);
1454         iu = __srp_get_tx_iu(target, SRP_IU_TSK_MGMT);
1455         spin_unlock_irq(&target->lock);
1456
1457         if (!iu)
1458                 return -1;
1459
1460         ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
1461                                    DMA_TO_DEVICE);
1462         tsk_mgmt = iu->buf;
1463         memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1464
1465         tsk_mgmt->opcode        = SRP_TSK_MGMT;
1466         tsk_mgmt->lun           = cpu_to_be64((u64) lun << 48);
1467         tsk_mgmt->tag           = req_tag | SRP_TAG_TSK_MGMT;
1468         tsk_mgmt->tsk_mgmt_func = func;
1469         tsk_mgmt->task_tag      = req_tag;
1470
1471         ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
1472                                       DMA_TO_DEVICE);
1473         if (srp_post_send(target, iu, sizeof *tsk_mgmt)) {
1474                 srp_put_tx_iu(target, iu, SRP_IU_TSK_MGMT);
1475                 return -1;
1476         }
1477
1478         if (!wait_for_completion_timeout(&target->tsk_mgmt_done,
1479                                          msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1480                 return -1;
1481
1482         return 0;
1483 }
1484
1485 static int srp_abort(struct scsi_cmnd *scmnd)
1486 {
1487         struct srp_target_port *target = host_to_target(scmnd->device->host);
1488         struct srp_request *req = (struct srp_request *) scmnd->host_scribble;
1489         int ret = SUCCESS;
1490
1491         shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
1492
1493         if (!req || target->qp_in_error)
1494                 return FAILED;
1495         if (srp_send_tsk_mgmt(target, req->index, scmnd->device->lun,
1496                               SRP_TSK_ABORT_TASK))
1497                 return FAILED;
1498
1499         if (req->scmnd) {
1500                 if (!target->tsk_mgmt_status) {
1501                         srp_remove_req(target, req, 0);
1502                         scmnd->result = DID_ABORT << 16;
1503                 } else
1504                         ret = FAILED;
1505         }
1506
1507         return ret;
1508 }
1509
1510 static int srp_reset_device(struct scsi_cmnd *scmnd)
1511 {
1512         struct srp_target_port *target = host_to_target(scmnd->device->host);
1513         int i;
1514
1515         shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
1516
1517         if (target->qp_in_error)
1518                 return FAILED;
1519         if (srp_send_tsk_mgmt(target, SRP_TAG_NO_REQ, scmnd->device->lun,
1520                               SRP_TSK_LUN_RESET))
1521                 return FAILED;
1522         if (target->tsk_mgmt_status)
1523                 return FAILED;
1524
1525         for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
1526                 struct srp_request *req = &target->req_ring[i];
1527                 if (req->scmnd && req->scmnd->device == scmnd->device)
1528                         srp_reset_req(target, req);
1529         }
1530
1531         return SUCCESS;
1532 }
1533
1534 static int srp_reset_host(struct scsi_cmnd *scmnd)
1535 {
1536         struct srp_target_port *target = host_to_target(scmnd->device->host);
1537         int ret = FAILED;
1538
1539         shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
1540
1541         if (!srp_reconnect_target(target))
1542                 ret = SUCCESS;
1543
1544         return ret;
1545 }
1546
1547 static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
1548                            char *buf)
1549 {
1550         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1551
1552         if (target->state == SRP_TARGET_DEAD ||
1553             target->state == SRP_TARGET_REMOVED)
1554                 return -ENODEV;
1555
1556         return sprintf(buf, "0x%016llx\n",
1557                        (unsigned long long) be64_to_cpu(target->id_ext));
1558 }
1559
1560 static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
1561                              char *buf)
1562 {
1563         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1564
1565         if (target->state == SRP_TARGET_DEAD ||
1566             target->state == SRP_TARGET_REMOVED)
1567                 return -ENODEV;
1568
1569         return sprintf(buf, "0x%016llx\n",
1570                        (unsigned long long) be64_to_cpu(target->ioc_guid));
1571 }
1572
1573 static ssize_t show_service_id(struct device *dev,
1574                                struct device_attribute *attr, char *buf)
1575 {
1576         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1577
1578         if (target->state == SRP_TARGET_DEAD ||
1579             target->state == SRP_TARGET_REMOVED)
1580                 return -ENODEV;
1581
1582         return sprintf(buf, "0x%016llx\n",
1583                        (unsigned long long) be64_to_cpu(target->service_id));
1584 }
1585
1586 static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
1587                          char *buf)
1588 {
1589         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1590
1591         if (target->state == SRP_TARGET_DEAD ||
1592             target->state == SRP_TARGET_REMOVED)
1593                 return -ENODEV;
1594
1595         return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
1596 }
1597
1598 static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
1599                          char *buf)
1600 {
1601         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1602
1603         if (target->state == SRP_TARGET_DEAD ||
1604             target->state == SRP_TARGET_REMOVED)
1605                 return -ENODEV;
1606
1607         return sprintf(buf, "%pI6\n", target->path.dgid.raw);
1608 }
1609
1610 static ssize_t show_orig_dgid(struct device *dev,
1611                               struct device_attribute *attr, char *buf)
1612 {
1613         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1614
1615         if (target->state == SRP_TARGET_DEAD ||
1616             target->state == SRP_TARGET_REMOVED)
1617                 return -ENODEV;
1618
1619         return sprintf(buf, "%pI6\n", target->orig_dgid);
1620 }
1621
1622 static ssize_t show_req_lim(struct device *dev,
1623                             struct device_attribute *attr, char *buf)
1624 {
1625         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1626
1627         if (target->state == SRP_TARGET_DEAD ||
1628             target->state == SRP_TARGET_REMOVED)
1629                 return -ENODEV;
1630
1631         return sprintf(buf, "%d\n", target->req_lim);
1632 }
1633
1634 static ssize_t show_zero_req_lim(struct device *dev,
1635                                  struct device_attribute *attr, char *buf)
1636 {
1637         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1638
1639         if (target->state == SRP_TARGET_DEAD ||
1640             target->state == SRP_TARGET_REMOVED)
1641                 return -ENODEV;
1642
1643         return sprintf(buf, "%d\n", target->zero_req_lim);
1644 }
1645
1646 static ssize_t show_local_ib_port(struct device *dev,
1647                                   struct device_attribute *attr, char *buf)
1648 {
1649         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1650
1651         return sprintf(buf, "%d\n", target->srp_host->port);
1652 }
1653
1654 static ssize_t show_local_ib_device(struct device *dev,
1655                                     struct device_attribute *attr, char *buf)
1656 {
1657         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1658
1659         return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
1660 }
1661
1662 static DEVICE_ATTR(id_ext,          S_IRUGO, show_id_ext,          NULL);
1663 static DEVICE_ATTR(ioc_guid,        S_IRUGO, show_ioc_guid,        NULL);
1664 static DEVICE_ATTR(service_id,      S_IRUGO, show_service_id,      NULL);
1665 static DEVICE_ATTR(pkey,            S_IRUGO, show_pkey,            NULL);
1666 static DEVICE_ATTR(dgid,            S_IRUGO, show_dgid,            NULL);
1667 static DEVICE_ATTR(orig_dgid,       S_IRUGO, show_orig_dgid,       NULL);
1668 static DEVICE_ATTR(req_lim,         S_IRUGO, show_req_lim,         NULL);
1669 static DEVICE_ATTR(zero_req_lim,    S_IRUGO, show_zero_req_lim,    NULL);
1670 static DEVICE_ATTR(local_ib_port,   S_IRUGO, show_local_ib_port,   NULL);
1671 static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
1672
1673 static struct device_attribute *srp_host_attrs[] = {
1674         &dev_attr_id_ext,
1675         &dev_attr_ioc_guid,
1676         &dev_attr_service_id,
1677         &dev_attr_pkey,
1678         &dev_attr_dgid,
1679         &dev_attr_orig_dgid,
1680         &dev_attr_req_lim,
1681         &dev_attr_zero_req_lim,
1682         &dev_attr_local_ib_port,
1683         &dev_attr_local_ib_device,
1684         NULL
1685 };
1686
1687 static struct scsi_host_template srp_template = {
1688         .module                         = THIS_MODULE,
1689         .name                           = "InfiniBand SRP initiator",
1690         .proc_name                      = DRV_NAME,
1691         .info                           = srp_target_info,
1692         .queuecommand                   = srp_queuecommand,
1693         .eh_abort_handler               = srp_abort,
1694         .eh_device_reset_handler        = srp_reset_device,
1695         .eh_host_reset_handler          = srp_reset_host,
1696         .can_queue                      = SRP_CMD_SQ_SIZE,
1697         .this_id                        = -1,
1698         .cmd_per_lun                    = SRP_CMD_SQ_SIZE,
1699         .use_clustering                 = ENABLE_CLUSTERING,
1700         .shost_attrs                    = srp_host_attrs
1701 };
1702
1703 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1704 {
1705         struct srp_rport_identifiers ids;
1706         struct srp_rport *rport;
1707
1708         sprintf(target->target_name, "SRP.T10:%016llX",
1709                  (unsigned long long) be64_to_cpu(target->id_ext));
1710
1711         if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
1712                 return -ENODEV;
1713
1714         memcpy(ids.port_id, &target->id_ext, 8);
1715         memcpy(ids.port_id + 8, &target->ioc_guid, 8);
1716         ids.roles = SRP_RPORT_ROLE_TARGET;
1717         rport = srp_rport_add(target->scsi_host, &ids);
1718         if (IS_ERR(rport)) {
1719                 scsi_remove_host(target->scsi_host);
1720                 return PTR_ERR(rport);
1721         }
1722
1723         spin_lock(&host->target_lock);
1724         list_add_tail(&target->list, &host->target_list);
1725         spin_unlock(&host->target_lock);
1726
1727         target->state = SRP_TARGET_LIVE;
1728
1729         scsi_scan_target(&target->scsi_host->shost_gendev,
1730                          0, target->scsi_id, SCAN_WILD_CARD, 0);
1731
1732         return 0;
1733 }
1734
1735 static void srp_release_dev(struct device *dev)
1736 {
1737         struct srp_host *host =
1738                 container_of(dev, struct srp_host, dev);
1739
1740         complete(&host->released);
1741 }
1742
1743 static struct class srp_class = {
1744         .name    = "infiniband_srp",
1745         .dev_release = srp_release_dev
1746 };
1747
1748 /*
1749  * Target ports are added by writing
1750  *
1751  *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1752  *     pkey=<P_Key>,service_id=<service ID>
1753  *
1754  * to the add_target sysfs attribute.
1755  */
1756 enum {
1757         SRP_OPT_ERR             = 0,
1758         SRP_OPT_ID_EXT          = 1 << 0,
1759         SRP_OPT_IOC_GUID        = 1 << 1,
1760         SRP_OPT_DGID            = 1 << 2,
1761         SRP_OPT_PKEY            = 1 << 3,
1762         SRP_OPT_SERVICE_ID      = 1 << 4,
1763         SRP_OPT_MAX_SECT        = 1 << 5,
1764         SRP_OPT_MAX_CMD_PER_LUN = 1 << 6,
1765         SRP_OPT_IO_CLASS        = 1 << 7,
1766         SRP_OPT_INITIATOR_EXT   = 1 << 8,
1767         SRP_OPT_ALL             = (SRP_OPT_ID_EXT       |
1768                                    SRP_OPT_IOC_GUID     |
1769                                    SRP_OPT_DGID         |
1770                                    SRP_OPT_PKEY         |
1771                                    SRP_OPT_SERVICE_ID),
1772 };
1773
1774 static const match_table_t srp_opt_tokens = {
1775         { SRP_OPT_ID_EXT,               "id_ext=%s"             },
1776         { SRP_OPT_IOC_GUID,             "ioc_guid=%s"           },
1777         { SRP_OPT_DGID,                 "dgid=%s"               },
1778         { SRP_OPT_PKEY,                 "pkey=%x"               },
1779         { SRP_OPT_SERVICE_ID,           "service_id=%s"         },
1780         { SRP_OPT_MAX_SECT,             "max_sect=%d"           },
1781         { SRP_OPT_MAX_CMD_PER_LUN,      "max_cmd_per_lun=%d"    },
1782         { SRP_OPT_IO_CLASS,             "io_class=%x"           },
1783         { SRP_OPT_INITIATOR_EXT,        "initiator_ext=%s"      },
1784         { SRP_OPT_ERR,                  NULL                    }
1785 };
1786
1787 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1788 {
1789         char *options, *sep_opt;
1790         char *p;
1791         char dgid[3];
1792         substring_t args[MAX_OPT_ARGS];
1793         int opt_mask = 0;
1794         int token;
1795         int ret = -EINVAL;
1796         int i;
1797
1798         options = kstrdup(buf, GFP_KERNEL);
1799         if (!options)
1800                 return -ENOMEM;
1801
1802         sep_opt = options;
1803         while ((p = strsep(&sep_opt, ",")) != NULL) {
1804                 if (!*p)
1805                         continue;
1806
1807                 token = match_token(p, srp_opt_tokens, args);
1808                 opt_mask |= token;
1809
1810                 switch (token) {
1811                 case SRP_OPT_ID_EXT:
1812                         p = match_strdup(args);
1813                         if (!p) {
1814                                 ret = -ENOMEM;
1815                                 goto out;
1816                         }
1817                         target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1818                         kfree(p);
1819                         break;
1820
1821                 case SRP_OPT_IOC_GUID:
1822                         p = match_strdup(args);
1823                         if (!p) {
1824                                 ret = -ENOMEM;
1825                                 goto out;
1826                         }
1827                         target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1828                         kfree(p);
1829                         break;
1830
1831                 case SRP_OPT_DGID:
1832                         p = match_strdup(args);
1833                         if (!p) {
1834                                 ret = -ENOMEM;
1835                                 goto out;
1836                         }
1837                         if (strlen(p) != 32) {
1838                                 printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
1839                                 kfree(p);
1840                                 goto out;
1841                         }
1842
1843                         for (i = 0; i < 16; ++i) {
1844                                 strlcpy(dgid, p + i * 2, 3);
1845                                 target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
1846                         }
1847                         kfree(p);
1848                         memcpy(target->orig_dgid, target->path.dgid.raw, 16);
1849                         break;
1850
1851                 case SRP_OPT_PKEY:
1852                         if (match_hex(args, &token)) {
1853                                 printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
1854                                 goto out;
1855                         }
1856                         target->path.pkey = cpu_to_be16(token);
1857                         break;
1858
1859                 case SRP_OPT_SERVICE_ID:
1860                         p = match_strdup(args);
1861                         if (!p) {
1862                                 ret = -ENOMEM;
1863                                 goto out;
1864                         }
1865                         target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
1866                         target->path.service_id = target->service_id;
1867                         kfree(p);
1868                         break;
1869
1870                 case SRP_OPT_MAX_SECT:
1871                         if (match_int(args, &token)) {
1872                                 printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
1873                                 goto out;
1874                         }
1875                         target->scsi_host->max_sectors = token;
1876                         break;
1877
1878                 case SRP_OPT_MAX_CMD_PER_LUN:
1879                         if (match_int(args, &token)) {
1880                                 printk(KERN_WARNING PFX "bad max cmd_per_lun parameter '%s'\n", p);
1881                                 goto out;
1882                         }
1883                         target->scsi_host->cmd_per_lun = min(token, SRP_CMD_SQ_SIZE);
1884                         break;
1885
1886                 case SRP_OPT_IO_CLASS:
1887                         if (match_hex(args, &token)) {
1888                                 printk(KERN_WARNING PFX "bad  IO class parameter '%s' \n", p);
1889                                 goto out;
1890                         }
1891                         if (token != SRP_REV10_IB_IO_CLASS &&
1892                             token != SRP_REV16A_IB_IO_CLASS) {
1893                                 printk(KERN_WARNING PFX "unknown IO class parameter value"
1894                                        " %x specified (use %x or %x).\n",
1895                                        token, SRP_REV10_IB_IO_CLASS, SRP_REV16A_IB_IO_CLASS);
1896                                 goto out;
1897                         }
1898                         target->io_class = token;
1899                         break;
1900
1901                 case SRP_OPT_INITIATOR_EXT:
1902                         p = match_strdup(args);
1903                         if (!p) {
1904                                 ret = -ENOMEM;
1905                                 goto out;
1906                         }
1907                         target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1908                         kfree(p);
1909                         break;
1910
1911                 default:
1912                         printk(KERN_WARNING PFX "unknown parameter or missing value "
1913                                "'%s' in target creation request\n", p);
1914                         goto out;
1915                 }
1916         }
1917
1918         if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
1919                 ret = 0;
1920         else
1921                 for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
1922                         if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
1923                             !(srp_opt_tokens[i].token & opt_mask))
1924                                 printk(KERN_WARNING PFX "target creation request is "
1925                                        "missing parameter '%s'\n",
1926                                        srp_opt_tokens[i].pattern);
1927
1928 out:
1929         kfree(options);
1930         return ret;
1931 }
1932
1933 static ssize_t srp_create_target(struct device *dev,
1934                                  struct device_attribute *attr,
1935                                  const char *buf, size_t count)
1936 {
1937         struct srp_host *host =
1938                 container_of(dev, struct srp_host, dev);
1939         struct Scsi_Host *target_host;
1940         struct srp_target_port *target;
1941         int ret;
1942         int i;
1943
1944         target_host = scsi_host_alloc(&srp_template,
1945                                       sizeof (struct srp_target_port));
1946         if (!target_host)
1947                 return -ENOMEM;
1948
1949         target_host->transportt = ib_srp_transport_template;
1950         target_host->max_lun     = SRP_MAX_LUN;
1951         target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
1952
1953         target = host_to_target(target_host);
1954
1955         target->io_class   = SRP_REV16A_IB_IO_CLASS;
1956         target->scsi_host  = target_host;
1957         target->srp_host   = host;
1958         target->lkey       = host->srp_dev->mr->lkey;
1959         target->rkey       = host->srp_dev->mr->rkey;
1960
1961         spin_lock_init(&target->lock);
1962         INIT_LIST_HEAD(&target->free_tx);
1963         INIT_LIST_HEAD(&target->free_reqs);
1964         for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
1965                 target->req_ring[i].index = i;
1966                 list_add_tail(&target->req_ring[i].list, &target->free_reqs);
1967         }
1968
1969         ret = srp_parse_options(buf, target);
1970         if (ret)
1971                 goto err;
1972
1973         ib_query_gid(host->srp_dev->dev, host->port, 0, &target->path.sgid);
1974
1975         shost_printk(KERN_DEBUG, target->scsi_host, PFX
1976                      "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
1977                      "service_id %016llx dgid %pI6\n",
1978                (unsigned long long) be64_to_cpu(target->id_ext),
1979                (unsigned long long) be64_to_cpu(target->ioc_guid),
1980                be16_to_cpu(target->path.pkey),
1981                (unsigned long long) be64_to_cpu(target->service_id),
1982                target->path.dgid.raw);
1983
1984         ret = srp_create_target_ib(target);
1985         if (ret)
1986                 goto err;
1987
1988         ret = srp_new_cm_id(target);
1989         if (ret)
1990                 goto err_free;
1991
1992         target->qp_in_error = 0;
1993         ret = srp_connect_target(target);
1994         if (ret) {
1995                 shost_printk(KERN_ERR, target->scsi_host,
1996                              PFX "Connection failed\n");
1997                 goto err_cm_id;
1998         }
1999
2000         ret = srp_add_target(host, target);
2001         if (ret)
2002                 goto err_disconnect;
2003
2004         return count;
2005
2006 err_disconnect:
2007         srp_disconnect_target(target);
2008
2009 err_cm_id:
2010         ib_destroy_cm_id(target->cm_id);
2011
2012 err_free:
2013         srp_free_target_ib(target);
2014
2015 err:
2016         scsi_host_put(target_host);
2017
2018         return ret;
2019 }
2020
2021 static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
2022
2023 static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
2024                           char *buf)
2025 {
2026         struct srp_host *host = container_of(dev, struct srp_host, dev);
2027
2028         return sprintf(buf, "%s\n", host->srp_dev->dev->name);
2029 }
2030
2031 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
2032
2033 static ssize_t show_port(struct device *dev, struct device_attribute *attr,
2034                          char *buf)
2035 {
2036         struct srp_host *host = container_of(dev, struct srp_host, dev);
2037
2038         return sprintf(buf, "%d\n", host->port);
2039 }
2040
2041 static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
2042
2043 static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
2044 {
2045         struct srp_host *host;
2046
2047         host = kzalloc(sizeof *host, GFP_KERNEL);
2048         if (!host)
2049                 return NULL;
2050
2051         INIT_LIST_HEAD(&host->target_list);
2052         spin_lock_init(&host->target_lock);
2053         init_completion(&host->released);
2054         host->srp_dev = device;
2055         host->port = port;
2056
2057         host->dev.class = &srp_class;
2058         host->dev.parent = device->dev->dma_device;
2059         dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
2060
2061         if (device_register(&host->dev))
2062                 goto free_host;
2063         if (device_create_file(&host->dev, &dev_attr_add_target))
2064                 goto err_class;
2065         if (device_create_file(&host->dev, &dev_attr_ibdev))
2066                 goto err_class;
2067         if (device_create_file(&host->dev, &dev_attr_port))
2068                 goto err_class;
2069
2070         return host;
2071
2072 err_class:
2073         device_unregister(&host->dev);
2074
2075 free_host:
2076         kfree(host);
2077
2078         return NULL;
2079 }
2080
2081 static void srp_add_one(struct ib_device *device)
2082 {
2083         struct srp_device *srp_dev;
2084         struct ib_device_attr *dev_attr;
2085         struct ib_fmr_pool_param fmr_param;
2086         struct srp_host *host;
2087         int s, e, p;
2088
2089         dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
2090         if (!dev_attr)
2091                 return;
2092
2093         if (ib_query_device(device, dev_attr)) {
2094                 printk(KERN_WARNING PFX "Query device failed for %s\n",
2095                        device->name);
2096                 goto free_attr;
2097         }
2098
2099         srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
2100         if (!srp_dev)
2101                 goto free_attr;
2102
2103         /*
2104          * Use the smallest page size supported by the HCA, down to a
2105          * minimum of 512 bytes (which is the smallest sector that a
2106          * SCSI command will ever carry).
2107          */
2108         srp_dev->fmr_page_shift = max(9, ffs(dev_attr->page_size_cap) - 1);
2109         srp_dev->fmr_page_size  = 1 << srp_dev->fmr_page_shift;
2110         srp_dev->fmr_page_mask  = ~((u64) srp_dev->fmr_page_size - 1);
2111
2112         INIT_LIST_HEAD(&srp_dev->dev_list);
2113
2114         srp_dev->dev = device;
2115         srp_dev->pd  = ib_alloc_pd(device);
2116         if (IS_ERR(srp_dev->pd))
2117                 goto free_dev;
2118
2119         srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
2120                                     IB_ACCESS_LOCAL_WRITE |
2121                                     IB_ACCESS_REMOTE_READ |
2122                                     IB_ACCESS_REMOTE_WRITE);
2123         if (IS_ERR(srp_dev->mr))
2124                 goto err_pd;
2125
2126         memset(&fmr_param, 0, sizeof fmr_param);
2127         fmr_param.pool_size         = SRP_FMR_POOL_SIZE;
2128         fmr_param.dirty_watermark   = SRP_FMR_DIRTY_SIZE;
2129         fmr_param.cache             = 1;
2130         fmr_param.max_pages_per_fmr = SRP_FMR_SIZE;
2131         fmr_param.page_shift        = srp_dev->fmr_page_shift;
2132         fmr_param.access            = (IB_ACCESS_LOCAL_WRITE |
2133                                        IB_ACCESS_REMOTE_WRITE |
2134                                        IB_ACCESS_REMOTE_READ);
2135
2136         srp_dev->fmr_pool = ib_create_fmr_pool(srp_dev->pd, &fmr_param);
2137         if (IS_ERR(srp_dev->fmr_pool))
2138                 srp_dev->fmr_pool = NULL;
2139
2140         if (device->node_type == RDMA_NODE_IB_SWITCH) {
2141                 s = 0;
2142                 e = 0;
2143         } else {
2144                 s = 1;
2145                 e = device->phys_port_cnt;
2146         }
2147
2148         for (p = s; p <= e; ++p) {
2149                 host = srp_add_port(srp_dev, p);
2150                 if (host)
2151                         list_add_tail(&host->list, &srp_dev->dev_list);
2152         }
2153
2154         ib_set_client_data(device, &srp_client, srp_dev);
2155
2156         goto free_attr;
2157
2158 err_pd:
2159         ib_dealloc_pd(srp_dev->pd);
2160
2161 free_dev:
2162         kfree(srp_dev);
2163
2164 free_attr:
2165         kfree(dev_attr);
2166 }
2167
2168 static void srp_remove_one(struct ib_device *device)
2169 {
2170         struct srp_device *srp_dev;
2171         struct srp_host *host, *tmp_host;
2172         LIST_HEAD(target_list);
2173         struct srp_target_port *target, *tmp_target;
2174
2175         srp_dev = ib_get_client_data(device, &srp_client);
2176
2177         list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
2178                 device_unregister(&host->dev);
2179                 /*
2180                  * Wait for the sysfs entry to go away, so that no new
2181                  * target ports can be created.
2182                  */
2183                 wait_for_completion(&host->released);
2184
2185                 /*
2186                  * Mark all target ports as removed, so we stop queueing
2187                  * commands and don't try to reconnect.
2188                  */
2189                 spin_lock(&host->target_lock);
2190                 list_for_each_entry(target, &host->target_list, list) {
2191                         spin_lock_irq(&target->lock);
2192                         target->state = SRP_TARGET_REMOVED;
2193                         spin_unlock_irq(&target->lock);
2194                 }
2195                 spin_unlock(&host->target_lock);
2196
2197                 /*
2198                  * Wait for any reconnection tasks that may have
2199                  * started before we marked our target ports as
2200                  * removed, and any target port removal tasks.
2201                  */
2202                 flush_scheduled_work();
2203
2204                 list_for_each_entry_safe(target, tmp_target,
2205                                          &host->target_list, list) {
2206                         srp_remove_host(target->scsi_host);
2207                         scsi_remove_host(target->scsi_host);
2208                         srp_disconnect_target(target);
2209                         ib_destroy_cm_id(target->cm_id);
2210                         srp_free_target_ib(target);
2211                         scsi_host_put(target->scsi_host);
2212                 }
2213
2214                 kfree(host);
2215         }
2216
2217         if (srp_dev->fmr_pool)
2218                 ib_destroy_fmr_pool(srp_dev->fmr_pool);
2219         ib_dereg_mr(srp_dev->mr);
2220         ib_dealloc_pd(srp_dev->pd);
2221
2222         kfree(srp_dev);
2223 }
2224
2225 static struct srp_function_template ib_srp_transport_functions = {
2226 };
2227
2228 static int __init srp_init_module(void)
2229 {
2230         int ret;
2231
2232         BUILD_BUG_ON(FIELD_SIZEOF(struct ib_wc, wr_id) < sizeof(void *));
2233
2234         if (srp_sg_tablesize > 255) {
2235                 printk(KERN_WARNING PFX "Clamping srp_sg_tablesize to 255\n");
2236                 srp_sg_tablesize = 255;
2237         }
2238
2239         ib_srp_transport_template =
2240                 srp_attach_transport(&ib_srp_transport_functions);
2241         if (!ib_srp_transport_template)
2242                 return -ENOMEM;
2243
2244         srp_template.sg_tablesize = srp_sg_tablesize;
2245         srp_max_iu_len = (sizeof (struct srp_cmd) +
2246                           sizeof (struct srp_indirect_buf) +
2247                           srp_sg_tablesize * 16);
2248
2249         ret = class_register(&srp_class);
2250         if (ret) {
2251                 printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
2252                 srp_release_transport(ib_srp_transport_template);
2253                 return ret;
2254         }
2255
2256         ib_sa_register_client(&srp_sa_client);
2257
2258         ret = ib_register_client(&srp_client);
2259         if (ret) {
2260                 printk(KERN_ERR PFX "couldn't register IB client\n");
2261                 srp_release_transport(ib_srp_transport_template);
2262                 ib_sa_unregister_client(&srp_sa_client);
2263                 class_unregister(&srp_class);
2264                 return ret;
2265         }
2266
2267         return 0;
2268 }
2269
2270 static void __exit srp_cleanup_module(void)
2271 {
2272         ib_unregister_client(&srp_client);
2273         ib_sa_unregister_client(&srp_sa_client);
2274         class_unregister(&srp_class);
2275         srp_release_transport(ib_srp_transport_template);
2276 }
2277
2278 module_init(srp_init_module);
2279 module_exit(srp_cleanup_module);