x86/sev-es: Do not support MMIO to/from encrypted memory
[linux-2.6-microblaze.git] / drivers / infiniband / ulp / iser / iser_verbs.c
1 /*
2  * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
3  * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
4  * Copyright (c) 2013-2014 Mellanox Technologies. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  */
34 #include <linux/kernel.h>
35 #include <linux/module.h>
36 #include <linux/slab.h>
37 #include <linux/delay.h>
38
39 #include "iscsi_iser.h"
40
41 #define ISCSI_ISER_MAX_CONN     8
42 #define ISER_MAX_RX_LEN         (ISER_QP_MAX_RECV_DTOS * ISCSI_ISER_MAX_CONN)
43 #define ISER_MAX_TX_LEN         (ISER_QP_MAX_REQ_DTOS  * ISCSI_ISER_MAX_CONN)
44 #define ISER_MAX_CQ_LEN         (ISER_MAX_RX_LEN + ISER_MAX_TX_LEN + \
45                                  ISCSI_ISER_MAX_CONN)
46
47 static void iser_qp_event_callback(struct ib_event *cause, void *context)
48 {
49         iser_err("qp event %s (%d)\n",
50                  ib_event_msg(cause->event), cause->event);
51 }
52
53 static void iser_event_handler(struct ib_event_handler *handler,
54                                 struct ib_event *event)
55 {
56         iser_err("async event %s (%d) on device %s port %d\n",
57                  ib_event_msg(event->event), event->event,
58                 dev_name(&event->device->dev), event->element.port_num);
59 }
60
61 /*
62  * iser_create_device_ib_res - creates Protection Domain (PD), Completion
63  * Queue (CQ), DMA Memory Region (DMA MR) with the device associated with
64  * the adaptor.
65  *
66  * Return: 0 on success, -1 on failure
67  */
68 static int iser_create_device_ib_res(struct iser_device *device)
69 {
70         struct ib_device *ib_dev = device->ib_device;
71
72         if (!(ib_dev->attrs.device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS)) {
73                 iser_err("IB device does not support memory registrations\n");
74                 return -1;
75         }
76
77         device->pd = ib_alloc_pd(ib_dev,
78                 iser_always_reg ? 0 : IB_PD_UNSAFE_GLOBAL_RKEY);
79         if (IS_ERR(device->pd))
80                 goto pd_err;
81
82         INIT_IB_EVENT_HANDLER(&device->event_handler, ib_dev,
83                               iser_event_handler);
84         ib_register_event_handler(&device->event_handler);
85         return 0;
86
87 pd_err:
88         iser_err("failed to allocate an IB resource\n");
89         return -1;
90 }
91
92 /*
93  * iser_free_device_ib_res - destroy/dealloc/dereg the DMA MR,
94  * CQ and PD created with the device associated with the adaptor.
95  */
96 static void iser_free_device_ib_res(struct iser_device *device)
97 {
98         ib_unregister_event_handler(&device->event_handler);
99         ib_dealloc_pd(device->pd);
100
101         device->pd = NULL;
102 }
103
104 static struct iser_fr_desc *
105 iser_create_fastreg_desc(struct iser_device *device,
106                          struct ib_pd *pd,
107                          bool pi_enable,
108                          unsigned int size)
109 {
110         struct iser_fr_desc *desc;
111         struct ib_device *ib_dev = device->ib_device;
112         enum ib_mr_type mr_type;
113         int ret;
114
115         desc = kzalloc(sizeof(*desc), GFP_KERNEL);
116         if (!desc)
117                 return ERR_PTR(-ENOMEM);
118
119         if (ib_dev->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG)
120                 mr_type = IB_MR_TYPE_SG_GAPS;
121         else
122                 mr_type = IB_MR_TYPE_MEM_REG;
123
124         desc->rsc.mr = ib_alloc_mr(pd, mr_type, size);
125         if (IS_ERR(desc->rsc.mr)) {
126                 ret = PTR_ERR(desc->rsc.mr);
127                 iser_err("Failed to allocate ib_fast_reg_mr err=%d\n", ret);
128                 goto err_alloc_mr;
129         }
130
131         if (pi_enable) {
132                 desc->rsc.sig_mr = ib_alloc_mr_integrity(pd, size, size);
133                 if (IS_ERR(desc->rsc.sig_mr)) {
134                         ret = PTR_ERR(desc->rsc.sig_mr);
135                         iser_err("Failed to allocate sig_mr err=%d\n", ret);
136                         goto err_alloc_mr_integrity;
137                 }
138         }
139         desc->rsc.mr_valid = 0;
140
141         return desc;
142
143 err_alloc_mr_integrity:
144         ib_dereg_mr(desc->rsc.mr);
145 err_alloc_mr:
146         kfree(desc);
147
148         return ERR_PTR(ret);
149 }
150
151 static void iser_destroy_fastreg_desc(struct iser_fr_desc *desc)
152 {
153         struct iser_reg_resources *res = &desc->rsc;
154
155         ib_dereg_mr(res->mr);
156         if (res->sig_mr) {
157                 ib_dereg_mr(res->sig_mr);
158                 res->sig_mr = NULL;
159         }
160         kfree(desc);
161 }
162
163 /**
164  * iser_alloc_fastreg_pool - Creates pool of fast_reg descriptors
165  * for fast registration work requests.
166  * @ib_conn: connection RDMA resources
167  * @cmds_max: max number of SCSI commands for this connection
168  * @size: max number of pages per map request
169  *
170  * Return: 0 on success, or errno code on failure
171  */
172 int iser_alloc_fastreg_pool(struct ib_conn *ib_conn,
173                             unsigned cmds_max,
174                             unsigned int size)
175 {
176         struct iser_device *device = ib_conn->device;
177         struct iser_fr_pool *fr_pool = &ib_conn->fr_pool;
178         struct iser_fr_desc *desc;
179         int i, ret;
180
181         INIT_LIST_HEAD(&fr_pool->list);
182         INIT_LIST_HEAD(&fr_pool->all_list);
183         spin_lock_init(&fr_pool->lock);
184         fr_pool->size = 0;
185         for (i = 0; i < cmds_max; i++) {
186                 desc = iser_create_fastreg_desc(device, device->pd,
187                                                 ib_conn->pi_support, size);
188                 if (IS_ERR(desc)) {
189                         ret = PTR_ERR(desc);
190                         goto err;
191                 }
192
193                 list_add_tail(&desc->list, &fr_pool->list);
194                 list_add_tail(&desc->all_list, &fr_pool->all_list);
195                 fr_pool->size++;
196         }
197
198         return 0;
199
200 err:
201         iser_free_fastreg_pool(ib_conn);
202         return ret;
203 }
204
205 /**
206  * iser_free_fastreg_pool - releases the pool of fast_reg descriptors
207  * @ib_conn: connection RDMA resources
208  */
209 void iser_free_fastreg_pool(struct ib_conn *ib_conn)
210 {
211         struct iser_fr_pool *fr_pool = &ib_conn->fr_pool;
212         struct iser_fr_desc *desc, *tmp;
213         int i = 0;
214
215         if (list_empty(&fr_pool->all_list))
216                 return;
217
218         iser_info("freeing conn %p fr pool\n", ib_conn);
219
220         list_for_each_entry_safe(desc, tmp, &fr_pool->all_list, all_list) {
221                 list_del(&desc->all_list);
222                 iser_destroy_fastreg_desc(desc);
223                 ++i;
224         }
225
226         if (i < fr_pool->size)
227                 iser_warn("pool still has %d regions registered\n",
228                           fr_pool->size - i);
229 }
230
231 /*
232  * iser_create_ib_conn_res - Queue-Pair (QP)
233  *
234  * Return: 0 on success, -1 on failure
235  */
236 static int iser_create_ib_conn_res(struct ib_conn *ib_conn)
237 {
238         struct iser_conn *iser_conn = to_iser_conn(ib_conn);
239         struct iser_device      *device;
240         struct ib_device        *ib_dev;
241         struct ib_qp_init_attr  init_attr;
242         int                     ret = -ENOMEM;
243         unsigned int max_send_wr, cq_size;
244
245         BUG_ON(ib_conn->device == NULL);
246
247         device = ib_conn->device;
248         ib_dev = device->ib_device;
249
250         if (ib_conn->pi_support)
251                 max_send_wr = ISER_QP_SIG_MAX_REQ_DTOS + 1;
252         else
253                 max_send_wr = ISER_QP_MAX_REQ_DTOS + 1;
254         max_send_wr = min_t(unsigned int, max_send_wr,
255                             (unsigned int)ib_dev->attrs.max_qp_wr);
256
257         cq_size = max_send_wr + ISER_QP_MAX_RECV_DTOS;
258         ib_conn->cq = ib_cq_pool_get(ib_dev, cq_size, -1, IB_POLL_SOFTIRQ);
259         if (IS_ERR(ib_conn->cq)) {
260                 ret = PTR_ERR(ib_conn->cq);
261                 goto cq_err;
262         }
263         ib_conn->cq_size = cq_size;
264
265         memset(&init_attr, 0, sizeof(init_attr));
266
267         init_attr.event_handler = iser_qp_event_callback;
268         init_attr.qp_context    = (void *)ib_conn;
269         init_attr.send_cq       = ib_conn->cq;
270         init_attr.recv_cq       = ib_conn->cq;
271         init_attr.cap.max_recv_wr  = ISER_QP_MAX_RECV_DTOS;
272         init_attr.cap.max_send_sge = 2;
273         init_attr.cap.max_recv_sge = 1;
274         init_attr.sq_sig_type   = IB_SIGNAL_REQ_WR;
275         init_attr.qp_type       = IB_QPT_RC;
276         init_attr.cap.max_send_wr = max_send_wr;
277         if (ib_conn->pi_support)
278                 init_attr.create_flags |= IB_QP_CREATE_INTEGRITY_EN;
279         iser_conn->max_cmds = ISER_GET_MAX_XMIT_CMDS(max_send_wr - 1);
280
281         ret = rdma_create_qp(ib_conn->cma_id, device->pd, &init_attr);
282         if (ret)
283                 goto out_err;
284
285         ib_conn->qp = ib_conn->cma_id->qp;
286         iser_info("setting conn %p cma_id %p qp %p max_send_wr %d\n",
287                   ib_conn, ib_conn->cma_id,
288                   ib_conn->cma_id->qp, max_send_wr);
289         return ret;
290
291 out_err:
292         ib_cq_pool_put(ib_conn->cq, ib_conn->cq_size);
293 cq_err:
294         iser_err("unable to alloc mem or create resource, err %d\n", ret);
295
296         return ret;
297 }
298
299 /*
300  * based on the resolved device node GUID see if there already allocated
301  * device for this device. If there's no such, create one.
302  */
303 static
304 struct iser_device *iser_device_find_by_ib_device(struct rdma_cm_id *cma_id)
305 {
306         struct iser_device *device;
307
308         mutex_lock(&ig.device_list_mutex);
309
310         list_for_each_entry(device, &ig.device_list, ig_list)
311                 /* find if there's a match using the node GUID */
312                 if (device->ib_device->node_guid == cma_id->device->node_guid)
313                         goto inc_refcnt;
314
315         device = kzalloc(sizeof *device, GFP_KERNEL);
316         if (device == NULL)
317                 goto out;
318
319         /* assign this device to the device */
320         device->ib_device = cma_id->device;
321         /* init the device and link it into ig device list */
322         if (iser_create_device_ib_res(device)) {
323                 kfree(device);
324                 device = NULL;
325                 goto out;
326         }
327         list_add(&device->ig_list, &ig.device_list);
328
329 inc_refcnt:
330         device->refcount++;
331 out:
332         mutex_unlock(&ig.device_list_mutex);
333         return device;
334 }
335
336 /* if there's no demand for this device, release it */
337 static void iser_device_try_release(struct iser_device *device)
338 {
339         mutex_lock(&ig.device_list_mutex);
340         device->refcount--;
341         iser_info("device %p refcount %d\n", device, device->refcount);
342         if (!device->refcount) {
343                 iser_free_device_ib_res(device);
344                 list_del(&device->ig_list);
345                 kfree(device);
346         }
347         mutex_unlock(&ig.device_list_mutex);
348 }
349
350 /*
351  * Called with state mutex held
352  */
353 static int iser_conn_state_comp_exch(struct iser_conn *iser_conn,
354                                      enum iser_conn_state comp,
355                                      enum iser_conn_state exch)
356 {
357         int ret;
358
359         ret = (iser_conn->state == comp);
360         if (ret)
361                 iser_conn->state = exch;
362
363         return ret;
364 }
365
366 void iser_release_work(struct work_struct *work)
367 {
368         struct iser_conn *iser_conn;
369
370         iser_conn = container_of(work, struct iser_conn, release_work);
371
372         /* Wait for conn_stop to complete */
373         wait_for_completion(&iser_conn->stop_completion);
374         /* Wait for IB resouces cleanup to complete */
375         wait_for_completion(&iser_conn->ib_completion);
376
377         mutex_lock(&iser_conn->state_mutex);
378         iser_conn->state = ISER_CONN_DOWN;
379         mutex_unlock(&iser_conn->state_mutex);
380
381         iser_conn_release(iser_conn);
382 }
383
384 /**
385  * iser_free_ib_conn_res - release IB related resources
386  * @iser_conn: iser connection struct
387  * @destroy: indicator if we need to try to release the
388  *     iser device and memory regoins pool (only iscsi
389  *     shutdown and DEVICE_REMOVAL will use this).
390  *
391  * This routine is called with the iser state mutex held
392  * so the cm_id removal is out of here. It is Safe to
393  * be invoked multiple times.
394  */
395 static void iser_free_ib_conn_res(struct iser_conn *iser_conn,
396                                   bool destroy)
397 {
398         struct ib_conn *ib_conn = &iser_conn->ib_conn;
399         struct iser_device *device = ib_conn->device;
400
401         iser_info("freeing conn %p cma_id %p qp %p\n",
402                   iser_conn, ib_conn->cma_id, ib_conn->qp);
403
404         if (ib_conn->qp != NULL) {
405                 rdma_destroy_qp(ib_conn->cma_id);
406                 ib_cq_pool_put(ib_conn->cq, ib_conn->cq_size);
407                 ib_conn->qp = NULL;
408         }
409
410         if (destroy) {
411                 if (iser_conn->rx_descs)
412                         iser_free_rx_descriptors(iser_conn);
413
414                 if (device != NULL) {
415                         iser_device_try_release(device);
416                         ib_conn->device = NULL;
417                 }
418         }
419 }
420
421 /**
422  * iser_conn_release - Frees all conn objects and deallocs conn descriptor
423  * @iser_conn: iSER connection context
424  */
425 void iser_conn_release(struct iser_conn *iser_conn)
426 {
427         struct ib_conn *ib_conn = &iser_conn->ib_conn;
428
429         mutex_lock(&ig.connlist_mutex);
430         list_del(&iser_conn->conn_list);
431         mutex_unlock(&ig.connlist_mutex);
432
433         mutex_lock(&iser_conn->state_mutex);
434         /* In case we endup here without ep_disconnect being invoked. */
435         if (iser_conn->state != ISER_CONN_DOWN) {
436                 iser_warn("iser conn %p state %d, expected state down.\n",
437                           iser_conn, iser_conn->state);
438                 iscsi_destroy_endpoint(iser_conn->ep);
439                 iser_conn->state = ISER_CONN_DOWN;
440         }
441         /*
442          * In case we never got to bind stage, we still need to
443          * release IB resources (which is safe to call more than once).
444          */
445         iser_free_ib_conn_res(iser_conn, true);
446         mutex_unlock(&iser_conn->state_mutex);
447
448         if (ib_conn->cma_id != NULL) {
449                 rdma_destroy_id(ib_conn->cma_id);
450                 ib_conn->cma_id = NULL;
451         }
452
453         kfree(iser_conn);
454 }
455
456 /**
457  * iser_conn_terminate - triggers start of the disconnect procedures and
458  * waits for them to be done
459  * @iser_conn: iSER connection context
460  *
461  * Called with state mutex held
462  */
463 int iser_conn_terminate(struct iser_conn *iser_conn)
464 {
465         struct ib_conn *ib_conn = &iser_conn->ib_conn;
466         int err = 0;
467
468         /* terminate the iser conn only if the conn state is UP */
469         if (!iser_conn_state_comp_exch(iser_conn, ISER_CONN_UP,
470                                        ISER_CONN_TERMINATING))
471                 return 0;
472
473         iser_info("iser_conn %p state %d\n", iser_conn, iser_conn->state);
474
475         /* suspend queuing of new iscsi commands */
476         if (iser_conn->iscsi_conn)
477                 iscsi_suspend_queue(iser_conn->iscsi_conn);
478
479         /*
480          * In case we didn't already clean up the cma_id (peer initiated
481          * a disconnection), we need to Cause the CMA to change the QP
482          * state to ERROR.
483          */
484         if (ib_conn->cma_id) {
485                 err = rdma_disconnect(ib_conn->cma_id);
486                 if (err)
487                         iser_err("Failed to disconnect, conn: 0x%p err %d\n",
488                                  iser_conn, err);
489
490                 /* block until all flush errors are consumed */
491                 ib_drain_sq(ib_conn->qp);
492         }
493
494         return 1;
495 }
496
497 /*
498  * Called with state mutex held
499  */
500 static void iser_connect_error(struct rdma_cm_id *cma_id)
501 {
502         struct iser_conn *iser_conn;
503
504         iser_conn = (struct iser_conn *)cma_id->context;
505         iser_conn->state = ISER_CONN_TERMINATING;
506 }
507
508 static void
509 iser_calc_scsi_params(struct iser_conn *iser_conn,
510                       unsigned int max_sectors)
511 {
512         struct iser_device *device = iser_conn->ib_conn.device;
513         struct ib_device_attr *attr = &device->ib_device->attrs;
514         unsigned short sg_tablesize, sup_sg_tablesize;
515         unsigned short reserved_mr_pages;
516         u32 max_num_sg;
517
518         /*
519          * FRs without SG_GAPS can only map up to a (device) page per entry,
520          * but if the first entry is misaligned we'll end up using two entries
521          * (head and tail) for a single page worth data, so one additional
522          * entry is required.
523          */
524         if (attr->device_cap_flags & IB_DEVICE_SG_GAPS_REG)
525                 reserved_mr_pages = 0;
526         else
527                 reserved_mr_pages = 1;
528
529         if (iser_conn->ib_conn.pi_support)
530                 max_num_sg = attr->max_pi_fast_reg_page_list_len;
531         else
532                 max_num_sg = attr->max_fast_reg_page_list_len;
533
534         sg_tablesize = DIV_ROUND_UP(max_sectors * SECTOR_SIZE, SZ_4K);
535         sup_sg_tablesize = min_t(uint, ISCSI_ISER_MAX_SG_TABLESIZE,
536                                  max_num_sg - reserved_mr_pages);
537         iser_conn->scsi_sg_tablesize = min(sg_tablesize, sup_sg_tablesize);
538         iser_conn->pages_per_mr =
539                 iser_conn->scsi_sg_tablesize + reserved_mr_pages;
540 }
541
542 /*
543  * Called with state mutex held
544  */
545 static void iser_addr_handler(struct rdma_cm_id *cma_id)
546 {
547         struct iser_device *device;
548         struct iser_conn   *iser_conn;
549         struct ib_conn   *ib_conn;
550         int    ret;
551
552         iser_conn = (struct iser_conn *)cma_id->context;
553         if (iser_conn->state != ISER_CONN_PENDING)
554                 /* bailout */
555                 return;
556
557         ib_conn = &iser_conn->ib_conn;
558         device = iser_device_find_by_ib_device(cma_id);
559         if (!device) {
560                 iser_err("device lookup/creation failed\n");
561                 iser_connect_error(cma_id);
562                 return;
563         }
564
565         ib_conn->device = device;
566
567         /* connection T10-PI support */
568         if (iser_pi_enable) {
569                 if (!(device->ib_device->attrs.device_cap_flags &
570                       IB_DEVICE_INTEGRITY_HANDOVER)) {
571                         iser_warn("T10-PI requested but not supported on %s, "
572                                   "continue without T10-PI\n",
573                                   dev_name(&ib_conn->device->ib_device->dev));
574                         ib_conn->pi_support = false;
575                 } else {
576                         ib_conn->pi_support = true;
577                 }
578         }
579
580         iser_calc_scsi_params(iser_conn, iser_max_sectors);
581
582         ret = rdma_resolve_route(cma_id, 1000);
583         if (ret) {
584                 iser_err("resolve route failed: %d\n", ret);
585                 iser_connect_error(cma_id);
586                 return;
587         }
588 }
589
590 /*
591  * Called with state mutex held
592  */
593 static void iser_route_handler(struct rdma_cm_id *cma_id)
594 {
595         struct rdma_conn_param conn_param;
596         int    ret;
597         struct iser_cm_hdr req_hdr;
598         struct iser_conn *iser_conn = (struct iser_conn *)cma_id->context;
599         struct ib_conn *ib_conn = &iser_conn->ib_conn;
600         struct ib_device *ib_dev = ib_conn->device->ib_device;
601
602         if (iser_conn->state != ISER_CONN_PENDING)
603                 /* bailout */
604                 return;
605
606         ret = iser_create_ib_conn_res(ib_conn);
607         if (ret)
608                 goto failure;
609
610         memset(&conn_param, 0, sizeof conn_param);
611         conn_param.responder_resources = ib_dev->attrs.max_qp_rd_atom;
612         conn_param.initiator_depth     = 1;
613         conn_param.retry_count         = 7;
614         conn_param.rnr_retry_count     = 6;
615
616         memset(&req_hdr, 0, sizeof(req_hdr));
617         req_hdr.flags = ISER_ZBVA_NOT_SUP;
618         if (!iser_always_reg)
619                 req_hdr.flags |= ISER_SEND_W_INV_NOT_SUP;
620         conn_param.private_data = (void *)&req_hdr;
621         conn_param.private_data_len = sizeof(struct iser_cm_hdr);
622
623         ret = rdma_connect(cma_id, &conn_param);
624         if (ret) {
625                 iser_err("failure connecting: %d\n", ret);
626                 goto failure;
627         }
628
629         return;
630 failure:
631         iser_connect_error(cma_id);
632 }
633
634 static void iser_connected_handler(struct rdma_cm_id *cma_id,
635                                    const void *private_data)
636 {
637         struct iser_conn *iser_conn;
638         struct ib_qp_attr attr;
639         struct ib_qp_init_attr init_attr;
640
641         iser_conn = (struct iser_conn *)cma_id->context;
642         if (iser_conn->state != ISER_CONN_PENDING)
643                 /* bailout */
644                 return;
645
646         (void)ib_query_qp(cma_id->qp, &attr, ~0, &init_attr);
647         iser_info("remote qpn:%x my qpn:%x\n", attr.dest_qp_num, cma_id->qp->qp_num);
648
649         if (private_data) {
650                 u8 flags = *(u8 *)private_data;
651
652                 iser_conn->snd_w_inv = !(flags & ISER_SEND_W_INV_NOT_SUP);
653         }
654
655         iser_info("conn %p: negotiated %s invalidation\n",
656                   iser_conn, iser_conn->snd_w_inv ? "remote" : "local");
657
658         iser_conn->state = ISER_CONN_UP;
659         complete(&iser_conn->up_completion);
660 }
661
662 static void iser_disconnected_handler(struct rdma_cm_id *cma_id)
663 {
664         struct iser_conn *iser_conn = (struct iser_conn *)cma_id->context;
665
666         if (iser_conn_terminate(iser_conn)) {
667                 if (iser_conn->iscsi_conn)
668                         iscsi_conn_failure(iser_conn->iscsi_conn,
669                                            ISCSI_ERR_CONN_FAILED);
670                 else
671                         iser_err("iscsi_iser connection isn't bound\n");
672         }
673 }
674
675 static void iser_cleanup_handler(struct rdma_cm_id *cma_id,
676                                  bool destroy)
677 {
678         struct iser_conn *iser_conn = (struct iser_conn *)cma_id->context;
679
680         /*
681          * We are not guaranteed that we visited disconnected_handler
682          * by now, call it here to be safe that we handle CM drep
683          * and flush errors.
684          */
685         iser_disconnected_handler(cma_id);
686         iser_free_ib_conn_res(iser_conn, destroy);
687         complete(&iser_conn->ib_completion);
688 };
689
690 static int iser_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
691 {
692         struct iser_conn *iser_conn;
693         int ret = 0;
694
695         iser_conn = (struct iser_conn *)cma_id->context;
696         iser_info("%s (%d): status %d conn %p id %p\n",
697                   rdma_event_msg(event->event), event->event,
698                   event->status, cma_id->context, cma_id);
699
700         mutex_lock(&iser_conn->state_mutex);
701         switch (event->event) {
702         case RDMA_CM_EVENT_ADDR_RESOLVED:
703                 iser_addr_handler(cma_id);
704                 break;
705         case RDMA_CM_EVENT_ROUTE_RESOLVED:
706                 iser_route_handler(cma_id);
707                 break;
708         case RDMA_CM_EVENT_ESTABLISHED:
709                 iser_connected_handler(cma_id, event->param.conn.private_data);
710                 break;
711         case RDMA_CM_EVENT_REJECTED:
712                 iser_info("Connection rejected: %s\n",
713                          rdma_reject_msg(cma_id, event->status));
714                 fallthrough;
715         case RDMA_CM_EVENT_ADDR_ERROR:
716         case RDMA_CM_EVENT_ROUTE_ERROR:
717         case RDMA_CM_EVENT_CONNECT_ERROR:
718         case RDMA_CM_EVENT_UNREACHABLE:
719                 iser_connect_error(cma_id);
720                 break;
721         case RDMA_CM_EVENT_DISCONNECTED:
722         case RDMA_CM_EVENT_ADDR_CHANGE:
723         case RDMA_CM_EVENT_TIMEWAIT_EXIT:
724                 iser_cleanup_handler(cma_id, false);
725                 break;
726         case RDMA_CM_EVENT_DEVICE_REMOVAL:
727                 /*
728                  * we *must* destroy the device as we cannot rely
729                  * on iscsid to be around to initiate error handling.
730                  * also if we are not in state DOWN implicitly destroy
731                  * the cma_id.
732                  */
733                 iser_cleanup_handler(cma_id, true);
734                 if (iser_conn->state != ISER_CONN_DOWN) {
735                         iser_conn->ib_conn.cma_id = NULL;
736                         ret = 1;
737                 }
738                 break;
739         default:
740                 iser_err("Unexpected RDMA CM event: %s (%d)\n",
741                          rdma_event_msg(event->event), event->event);
742                 break;
743         }
744         mutex_unlock(&iser_conn->state_mutex);
745
746         return ret;
747 }
748
749 void iser_conn_init(struct iser_conn *iser_conn)
750 {
751         struct ib_conn *ib_conn = &iser_conn->ib_conn;
752
753         iser_conn->state = ISER_CONN_INIT;
754         init_completion(&iser_conn->stop_completion);
755         init_completion(&iser_conn->ib_completion);
756         init_completion(&iser_conn->up_completion);
757         INIT_LIST_HEAD(&iser_conn->conn_list);
758         mutex_init(&iser_conn->state_mutex);
759
760         ib_conn->post_recv_buf_count = 0;
761         ib_conn->reg_cqe.done = iser_reg_comp;
762 }
763
764  /**
765  * starts the process of connecting to the target
766  * sleeps until the connection is established or rejected
767  */
768 int iser_connect(struct iser_conn   *iser_conn,
769                  struct sockaddr    *src_addr,
770                  struct sockaddr    *dst_addr,
771                  int                 non_blocking)
772 {
773         struct ib_conn *ib_conn = &iser_conn->ib_conn;
774         int err = 0;
775
776         mutex_lock(&iser_conn->state_mutex);
777
778         sprintf(iser_conn->name, "%pISp", dst_addr);
779
780         iser_info("connecting to: %s\n", iser_conn->name);
781
782         /* the device is known only --after-- address resolution */
783         ib_conn->device = NULL;
784
785         iser_conn->state = ISER_CONN_PENDING;
786
787         ib_conn->cma_id = rdma_create_id(&init_net, iser_cma_handler,
788                                          (void *)iser_conn,
789                                          RDMA_PS_TCP, IB_QPT_RC);
790         if (IS_ERR(ib_conn->cma_id)) {
791                 err = PTR_ERR(ib_conn->cma_id);
792                 iser_err("rdma_create_id failed: %d\n", err);
793                 goto id_failure;
794         }
795
796         err = rdma_resolve_addr(ib_conn->cma_id, src_addr, dst_addr, 1000);
797         if (err) {
798                 iser_err("rdma_resolve_addr failed: %d\n", err);
799                 goto addr_failure;
800         }
801
802         if (!non_blocking) {
803                 wait_for_completion_interruptible(&iser_conn->up_completion);
804
805                 if (iser_conn->state != ISER_CONN_UP) {
806                         err =  -EIO;
807                         goto connect_failure;
808                 }
809         }
810         mutex_unlock(&iser_conn->state_mutex);
811
812         mutex_lock(&ig.connlist_mutex);
813         list_add(&iser_conn->conn_list, &ig.connlist);
814         mutex_unlock(&ig.connlist_mutex);
815         return 0;
816
817 id_failure:
818         ib_conn->cma_id = NULL;
819 addr_failure:
820         iser_conn->state = ISER_CONN_DOWN;
821 connect_failure:
822         mutex_unlock(&iser_conn->state_mutex);
823         iser_conn_release(iser_conn);
824         return err;
825 }
826
827 int iser_post_recvl(struct iser_conn *iser_conn)
828 {
829         struct ib_conn *ib_conn = &iser_conn->ib_conn;
830         struct iser_login_desc *desc = &iser_conn->login_desc;
831         struct ib_recv_wr wr;
832         int ib_ret;
833
834         desc->sge.addr = desc->rsp_dma;
835         desc->sge.length = ISER_RX_LOGIN_SIZE;
836         desc->sge.lkey = ib_conn->device->pd->local_dma_lkey;
837
838         desc->cqe.done = iser_login_rsp;
839         wr.wr_cqe = &desc->cqe;
840         wr.sg_list = &desc->sge;
841         wr.num_sge = 1;
842         wr.next = NULL;
843
844         ib_conn->post_recv_buf_count++;
845         ib_ret = ib_post_recv(ib_conn->qp, &wr, NULL);
846         if (ib_ret) {
847                 iser_err("ib_post_recv failed ret=%d\n", ib_ret);
848                 ib_conn->post_recv_buf_count--;
849         }
850
851         return ib_ret;
852 }
853
854 int iser_post_recvm(struct iser_conn *iser_conn, int count)
855 {
856         struct ib_conn *ib_conn = &iser_conn->ib_conn;
857         unsigned int my_rx_head = iser_conn->rx_desc_head;
858         struct iser_rx_desc *rx_desc;
859         struct ib_recv_wr *wr;
860         int i, ib_ret;
861
862         for (wr = ib_conn->rx_wr, i = 0; i < count; i++, wr++) {
863                 rx_desc = &iser_conn->rx_descs[my_rx_head];
864                 rx_desc->cqe.done = iser_task_rsp;
865                 wr->wr_cqe = &rx_desc->cqe;
866                 wr->sg_list = &rx_desc->rx_sg;
867                 wr->num_sge = 1;
868                 wr->next = wr + 1;
869                 my_rx_head = (my_rx_head + 1) & iser_conn->qp_max_recv_dtos_mask;
870         }
871
872         wr--;
873         wr->next = NULL; /* mark end of work requests list */
874
875         ib_conn->post_recv_buf_count += count;
876         ib_ret = ib_post_recv(ib_conn->qp, ib_conn->rx_wr, NULL);
877         if (unlikely(ib_ret)) {
878                 iser_err("ib_post_recv failed ret=%d\n", ib_ret);
879                 ib_conn->post_recv_buf_count -= count;
880         } else
881                 iser_conn->rx_desc_head = my_rx_head;
882
883         return ib_ret;
884 }
885
886
887 /**
888  * iser_post_send - Initiate a Send DTO operation
889  * @ib_conn: connection RDMA resources
890  * @tx_desc: iSER TX descriptor
891  * @signal: true to send work request as SIGNALED
892  *
893  * Return: 0 on success, -1 on failure
894  */
895 int iser_post_send(struct ib_conn *ib_conn, struct iser_tx_desc *tx_desc,
896                    bool signal)
897 {
898         struct ib_send_wr *wr = &tx_desc->send_wr;
899         struct ib_send_wr *first_wr;
900         int ib_ret;
901
902         ib_dma_sync_single_for_device(ib_conn->device->ib_device,
903                                       tx_desc->dma_addr, ISER_HEADERS_LEN,
904                                       DMA_TO_DEVICE);
905
906         wr->next = NULL;
907         wr->wr_cqe = &tx_desc->cqe;
908         wr->sg_list = tx_desc->tx_sg;
909         wr->num_sge = tx_desc->num_sge;
910         wr->opcode = IB_WR_SEND;
911         wr->send_flags = signal ? IB_SEND_SIGNALED : 0;
912
913         if (tx_desc->inv_wr.next)
914                 first_wr = &tx_desc->inv_wr;
915         else if (tx_desc->reg_wr.wr.next)
916                 first_wr = &tx_desc->reg_wr.wr;
917         else
918                 first_wr = wr;
919
920         ib_ret = ib_post_send(ib_conn->qp, first_wr, NULL);
921         if (unlikely(ib_ret))
922                 iser_err("ib_post_send failed, ret:%d opcode:%d\n",
923                          ib_ret, wr->opcode);
924
925         return ib_ret;
926 }
927
928 u8 iser_check_task_pi_status(struct iscsi_iser_task *iser_task,
929                              enum iser_data_dir cmd_dir, sector_t *sector)
930 {
931         struct iser_mem_reg *reg = &iser_task->rdma_reg[cmd_dir];
932         struct iser_fr_desc *desc = reg->mem_h;
933         unsigned long sector_size = iser_task->sc->device->sector_size;
934         struct ib_mr_status mr_status;
935         int ret;
936
937         if (desc && desc->sig_protected) {
938                 desc->sig_protected = false;
939                 ret = ib_check_mr_status(desc->rsc.sig_mr,
940                                          IB_MR_CHECK_SIG_STATUS, &mr_status);
941                 if (ret) {
942                         iser_err("ib_check_mr_status failed, ret %d\n", ret);
943                         /* Not a lot we can do, return ambiguous guard error */
944                         *sector = 0;
945                         return 0x1;
946                 }
947
948                 if (mr_status.fail_status & IB_MR_CHECK_SIG_STATUS) {
949                         sector_t sector_off = mr_status.sig_err.sig_err_offset;
950
951                         sector_div(sector_off, sector_size + 8);
952                         *sector = scsi_get_lba(iser_task->sc) + sector_off;
953
954                         iser_err("PI error found type %d at sector %llx "
955                                "expected %x vs actual %x\n",
956                                mr_status.sig_err.err_type,
957                                (unsigned long long)*sector,
958                                mr_status.sig_err.expected,
959                                mr_status.sig_err.actual);
960
961                         switch (mr_status.sig_err.err_type) {
962                         case IB_SIG_BAD_GUARD:
963                                 return 0x1;
964                         case IB_SIG_BAD_REFTAG:
965                                 return 0x3;
966                         case IB_SIG_BAD_APPTAG:
967                                 return 0x2;
968                         }
969                 }
970         }
971
972         return 0;
973 }
974
975 void iser_err_comp(struct ib_wc *wc, const char *type)
976 {
977         if (wc->status != IB_WC_WR_FLUSH_ERR) {
978                 struct iser_conn *iser_conn = to_iser_conn(wc->qp->qp_context);
979
980                 iser_err("%s failure: %s (%d) vend_err %#x\n", type,
981                          ib_wc_status_msg(wc->status), wc->status,
982                          wc->vendor_err);
983
984                 if (iser_conn->iscsi_conn)
985                         iscsi_conn_failure(iser_conn->iscsi_conn,
986                                            ISCSI_ERR_CONN_FAILED);
987         } else {
988                 iser_dbg("%s failure: %s (%d)\n", type,
989                          ib_wc_status_msg(wc->status), wc->status);
990         }
991 }