hc
2023-12-11 d2ccde1c8e90d38cee87a1b0309ad2827f3fd30d
kernel/drivers/s390/cio/vfio_ccw_drv.c
....@@ -3,9 +3,11 @@
33 * VFIO based Physical Subchannel device driver
44 *
55 * Copyright IBM Corp. 2017
6
+ * Copyright Red Hat, Inc. 2019
67 *
78 * Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
89 * Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
10
+ * Cornelia Huck <cohuck@redhat.com>
911 */
1012
1113 #include <linux/module.h>
....@@ -17,12 +19,19 @@
1719
1820 #include <asm/isc.h>
1921
22
+#include "chp.h"
2023 #include "ioasm.h"
2124 #include "css.h"
2225 #include "vfio_ccw_private.h"
2326
2427 struct workqueue_struct *vfio_ccw_work_q;
25
-struct kmem_cache *vfio_ccw_io_region;
28
+static struct kmem_cache *vfio_ccw_io_region;
29
+static struct kmem_cache *vfio_ccw_cmd_region;
30
+static struct kmem_cache *vfio_ccw_schib_region;
31
+static struct kmem_cache *vfio_ccw_crw_region;
32
+
33
+debug_info_t *vfio_ccw_debug_msg_id;
34
+debug_info_t *vfio_ccw_debug_trace_id;
2635
2736 /*
2837 * Helpers
....@@ -77,6 +86,7 @@
7786 struct vfio_ccw_private *private;
7887 struct irb *irb;
7988 bool is_final;
89
+ bool cp_is_finished = false;
8090
8191 private = container_of(work, struct vfio_ccw_private, io_work);
8292 irb = &private->irb;
....@@ -85,16 +95,35 @@
8595 (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT));
8696 if (scsw_is_solicited(&irb->scsw)) {
8797 cp_update_scsw(&private->cp, &irb->scsw);
88
- if (is_final)
98
+ if (is_final && private->state == VFIO_CCW_STATE_CP_PENDING) {
8999 cp_free(&private->cp);
100
+ cp_is_finished = true;
101
+ }
90102 }
103
+ mutex_lock(&private->io_mutex);
91104 memcpy(private->io_region->irb_area, irb, sizeof(*irb));
105
+ mutex_unlock(&private->io_mutex);
106
+
107
+ /*
108
+ * Reset to IDLE only if processing of a channel program
109
+ * has finished. Do not overwrite a possible processing
110
+ * state if the final interrupt was for HSCH or CSCH.
111
+ */
112
+ if (private->mdev && cp_is_finished)
113
+ private->state = VFIO_CCW_STATE_IDLE;
92114
93115 if (private->io_trigger)
94116 eventfd_signal(private->io_trigger, 1);
117
+}
95118
96
- if (private->mdev && is_final)
97
- private->state = VFIO_CCW_STATE_IDLE;
119
+static void vfio_ccw_crw_todo(struct work_struct *work)
120
+{
121
+ struct vfio_ccw_private *private;
122
+
123
+ private = container_of(work, struct vfio_ccw_private, crw_work);
124
+
125
+ if (!list_empty(&private->crw) && private->crw_trigger)
126
+ eventfd_signal(private->crw_trigger, 1);
98127 }
99128
100129 /*
....@@ -108,11 +137,23 @@
108137 vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_INTERRUPT);
109138 }
110139
140
+static void vfio_ccw_free_regions(struct vfio_ccw_private *private)
141
+{
142
+ if (private->crw_region)
143
+ kmem_cache_free(vfio_ccw_crw_region, private->crw_region);
144
+ if (private->schib_region)
145
+ kmem_cache_free(vfio_ccw_schib_region, private->schib_region);
146
+ if (private->cmd_region)
147
+ kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
148
+ if (private->io_region)
149
+ kmem_cache_free(vfio_ccw_io_region, private->io_region);
150
+}
151
+
111152 static int vfio_ccw_sch_probe(struct subchannel *sch)
112153 {
113154 struct pmcw *pmcw = &sch->schib.pmcw;
114155 struct vfio_ccw_private *private;
115
- int ret;
156
+ int ret = -ENOMEM;
116157
117158 if (pmcw->qf) {
118159 dev_warn(&sch->dev, "vfio: ccw: does not support QDIO: %s\n",
....@@ -124,15 +165,36 @@
124165 if (!private)
125166 return -ENOMEM;
126167
168
+ private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct ccw1),
169
+ GFP_KERNEL);
170
+ if (!private->cp.guest_cp)
171
+ goto out_free;
172
+
127173 private->io_region = kmem_cache_zalloc(vfio_ccw_io_region,
128174 GFP_KERNEL | GFP_DMA);
129
- if (!private->io_region) {
130
- kfree(private);
131
- return -ENOMEM;
132
- }
175
+ if (!private->io_region)
176
+ goto out_free;
177
+
178
+ private->cmd_region = kmem_cache_zalloc(vfio_ccw_cmd_region,
179
+ GFP_KERNEL | GFP_DMA);
180
+ if (!private->cmd_region)
181
+ goto out_free;
182
+
183
+ private->schib_region = kmem_cache_zalloc(vfio_ccw_schib_region,
184
+ GFP_KERNEL | GFP_DMA);
185
+
186
+ if (!private->schib_region)
187
+ goto out_free;
188
+
189
+ private->crw_region = kmem_cache_zalloc(vfio_ccw_crw_region,
190
+ GFP_KERNEL | GFP_DMA);
191
+
192
+ if (!private->crw_region)
193
+ goto out_free;
133194
134195 private->sch = sch;
135196 dev_set_drvdata(&sch->dev, private);
197
+ mutex_init(&private->io_mutex);
136198
137199 spin_lock_irq(sch->lock);
138200 private->state = VFIO_CCW_STATE_NOT_OPER;
....@@ -142,21 +204,32 @@
142204 if (ret)
143205 goto out_free;
144206
207
+ INIT_LIST_HEAD(&private->crw);
208
+ INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
209
+ INIT_WORK(&private->crw_work, vfio_ccw_crw_todo);
210
+ atomic_set(&private->avail, 1);
211
+ private->state = VFIO_CCW_STATE_STANDBY;
212
+
145213 ret = vfio_ccw_mdev_reg(sch);
146214 if (ret)
147215 goto out_disable;
148216
149
- INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
150
- atomic_set(&private->avail, 1);
151
- private->state = VFIO_CCW_STATE_STANDBY;
217
+ if (dev_get_uevent_suppress(&sch->dev)) {
218
+ dev_set_uevent_suppress(&sch->dev, 0);
219
+ kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
220
+ }
152221
222
+ VFIO_CCW_MSG_EVENT(4, "bound to subchannel %x.%x.%04x\n",
223
+ sch->schid.cssid, sch->schid.ssid,
224
+ sch->schid.sch_no);
153225 return 0;
154226
155227 out_disable:
156228 cio_disable_subchannel(sch);
157229 out_free:
158230 dev_set_drvdata(&sch->dev, NULL);
159
- kmem_cache_free(vfio_ccw_io_region, private->io_region);
231
+ vfio_ccw_free_regions(private);
232
+ kfree(private->cp.guest_cp);
160233 kfree(private);
161234 return ret;
162235 }
....@@ -164,16 +237,26 @@
164237 static int vfio_ccw_sch_remove(struct subchannel *sch)
165238 {
166239 struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev);
240
+ struct vfio_ccw_crw *crw, *temp;
167241
168242 vfio_ccw_sch_quiesce(sch);
243
+
244
+ list_for_each_entry_safe(crw, temp, &private->crw, next) {
245
+ list_del(&crw->next);
246
+ kfree(crw);
247
+ }
169248
170249 vfio_ccw_mdev_unreg(sch);
171250
172251 dev_set_drvdata(&sch->dev, NULL);
173252
174
- kmem_cache_free(vfio_ccw_io_region, private->io_region);
253
+ vfio_ccw_free_regions(private);
254
+ kfree(private->cp.guest_cp);
175255 kfree(private);
176256
257
+ VFIO_CCW_MSG_EVENT(4, "unbound from subchannel %x.%x.%04x\n",
258
+ sch->schid.cssid, sch->schid.ssid,
259
+ sch->schid.sch_no);
177260 return 0;
178261 }
179262
....@@ -205,23 +288,92 @@
205288 if (work_pending(&sch->todo_work))
206289 goto out_unlock;
207290
208
- if (cio_update_schib(sch)) {
209
- vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_NOT_OPER);
210
- rc = 0;
211
- goto out_unlock;
212
- }
213
-
214
- private = dev_get_drvdata(&sch->dev);
215
- if (private->state == VFIO_CCW_STATE_NOT_OPER) {
216
- private->state = private->mdev ? VFIO_CCW_STATE_IDLE :
217
- VFIO_CCW_STATE_STANDBY;
218
- }
219291 rc = 0;
292
+
293
+ if (cio_update_schib(sch))
294
+ vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_NOT_OPER);
220295
221296 out_unlock:
222297 spin_unlock_irqrestore(sch->lock, flags);
223298
224299 return rc;
300
+}
301
+
302
+static void vfio_ccw_queue_crw(struct vfio_ccw_private *private,
303
+ unsigned int rsc,
304
+ unsigned int erc,
305
+ unsigned int rsid)
306
+{
307
+ struct vfio_ccw_crw *crw;
308
+
309
+ /*
310
+ * If unable to allocate a CRW, just drop the event and
311
+ * carry on. The guest will either see a later one or
312
+ * learn when it issues its own store subchannel.
313
+ */
314
+ crw = kzalloc(sizeof(*crw), GFP_ATOMIC);
315
+ if (!crw)
316
+ return;
317
+
318
+ /*
319
+ * Build the CRW based on the inputs given to us.
320
+ */
321
+ crw->crw.rsc = rsc;
322
+ crw->crw.erc = erc;
323
+ crw->crw.rsid = rsid;
324
+
325
+ list_add_tail(&crw->next, &private->crw);
326
+ queue_work(vfio_ccw_work_q, &private->crw_work);
327
+}
328
+
329
+static int vfio_ccw_chp_event(struct subchannel *sch,
330
+ struct chp_link *link, int event)
331
+{
332
+ struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev);
333
+ int mask = chp_ssd_get_mask(&sch->ssd_info, link);
334
+ int retry = 255;
335
+
336
+ if (!private || !mask)
337
+ return 0;
338
+
339
+ trace_vfio_ccw_chp_event(private->sch->schid, mask, event);
340
+ VFIO_CCW_MSG_EVENT(2, "%pUl (%x.%x.%04x): mask=0x%x event=%d\n",
341
+ mdev_uuid(private->mdev), sch->schid.cssid,
342
+ sch->schid.ssid, sch->schid.sch_no,
343
+ mask, event);
344
+
345
+ if (cio_update_schib(sch))
346
+ return -ENODEV;
347
+
348
+ switch (event) {
349
+ case CHP_VARY_OFF:
350
+ /* Path logically turned off */
351
+ sch->opm &= ~mask;
352
+ sch->lpm &= ~mask;
353
+ if (sch->schib.pmcw.lpum & mask)
354
+ cio_cancel_halt_clear(sch, &retry);
355
+ break;
356
+ case CHP_OFFLINE:
357
+ /* Path is gone */
358
+ if (sch->schib.pmcw.lpum & mask)
359
+ cio_cancel_halt_clear(sch, &retry);
360
+ vfio_ccw_queue_crw(private, CRW_RSC_CPATH, CRW_ERC_PERRN,
361
+ link->chpid.id);
362
+ break;
363
+ case CHP_VARY_ON:
364
+ /* Path logically turned on */
365
+ sch->opm |= mask;
366
+ sch->lpm |= mask;
367
+ break;
368
+ case CHP_ONLINE:
369
+ /* Path became available */
370
+ sch->lpm |= mask & sch->opm;
371
+ vfio_ccw_queue_crw(private, CRW_RSC_CPATH, CRW_ERC_INIT,
372
+ link->chpid.id);
373
+ break;
374
+ }
375
+
376
+ return 0;
225377 }
226378
227379 static struct css_device_id vfio_ccw_sch_ids[] = {
....@@ -241,33 +393,109 @@
241393 .remove = vfio_ccw_sch_remove,
242394 .shutdown = vfio_ccw_sch_shutdown,
243395 .sch_event = vfio_ccw_sch_event,
396
+ .chp_event = vfio_ccw_chp_event,
244397 };
398
+
399
+static int __init vfio_ccw_debug_init(void)
400
+{
401
+ vfio_ccw_debug_msg_id = debug_register("vfio_ccw_msg", 16, 1,
402
+ 11 * sizeof(long));
403
+ if (!vfio_ccw_debug_msg_id)
404
+ goto out_unregister;
405
+ debug_register_view(vfio_ccw_debug_msg_id, &debug_sprintf_view);
406
+ debug_set_level(vfio_ccw_debug_msg_id, 2);
407
+ vfio_ccw_debug_trace_id = debug_register("vfio_ccw_trace", 16, 1, 16);
408
+ if (!vfio_ccw_debug_trace_id)
409
+ goto out_unregister;
410
+ debug_register_view(vfio_ccw_debug_trace_id, &debug_hex_ascii_view);
411
+ debug_set_level(vfio_ccw_debug_trace_id, 2);
412
+ return 0;
413
+
414
+out_unregister:
415
+ debug_unregister(vfio_ccw_debug_msg_id);
416
+ debug_unregister(vfio_ccw_debug_trace_id);
417
+ return -1;
418
+}
419
+
420
+static void vfio_ccw_debug_exit(void)
421
+{
422
+ debug_unregister(vfio_ccw_debug_msg_id);
423
+ debug_unregister(vfio_ccw_debug_trace_id);
424
+}
425
+
426
+static void vfio_ccw_destroy_regions(void)
427
+{
428
+ kmem_cache_destroy(vfio_ccw_crw_region);
429
+ kmem_cache_destroy(vfio_ccw_schib_region);
430
+ kmem_cache_destroy(vfio_ccw_cmd_region);
431
+ kmem_cache_destroy(vfio_ccw_io_region);
432
+}
245433
246434 static int __init vfio_ccw_sch_init(void)
247435 {
248436 int ret;
249437
438
+ ret = vfio_ccw_debug_init();
439
+ if (ret)
440
+ return ret;
441
+
250442 vfio_ccw_work_q = create_singlethread_workqueue("vfio-ccw");
251
- if (!vfio_ccw_work_q)
252
- return -ENOMEM;
443
+ if (!vfio_ccw_work_q) {
444
+ ret = -ENOMEM;
445
+ goto out_err;
446
+ }
253447
254448 vfio_ccw_io_region = kmem_cache_create_usercopy("vfio_ccw_io_region",
255449 sizeof(struct ccw_io_region), 0,
256450 SLAB_ACCOUNT, 0,
257451 sizeof(struct ccw_io_region), NULL);
258452 if (!vfio_ccw_io_region) {
259
- destroy_workqueue(vfio_ccw_work_q);
260
- return -ENOMEM;
453
+ ret = -ENOMEM;
454
+ goto out_err;
455
+ }
456
+
457
+ vfio_ccw_cmd_region = kmem_cache_create_usercopy("vfio_ccw_cmd_region",
458
+ sizeof(struct ccw_cmd_region), 0,
459
+ SLAB_ACCOUNT, 0,
460
+ sizeof(struct ccw_cmd_region), NULL);
461
+ if (!vfio_ccw_cmd_region) {
462
+ ret = -ENOMEM;
463
+ goto out_err;
464
+ }
465
+
466
+ vfio_ccw_schib_region = kmem_cache_create_usercopy("vfio_ccw_schib_region",
467
+ sizeof(struct ccw_schib_region), 0,
468
+ SLAB_ACCOUNT, 0,
469
+ sizeof(struct ccw_schib_region), NULL);
470
+
471
+ if (!vfio_ccw_schib_region) {
472
+ ret = -ENOMEM;
473
+ goto out_err;
474
+ }
475
+
476
+ vfio_ccw_crw_region = kmem_cache_create_usercopy("vfio_ccw_crw_region",
477
+ sizeof(struct ccw_crw_region), 0,
478
+ SLAB_ACCOUNT, 0,
479
+ sizeof(struct ccw_crw_region), NULL);
480
+
481
+ if (!vfio_ccw_crw_region) {
482
+ ret = -ENOMEM;
483
+ goto out_err;
261484 }
262485
263486 isc_register(VFIO_CCW_ISC);
264487 ret = css_driver_register(&vfio_ccw_sch_driver);
265488 if (ret) {
266489 isc_unregister(VFIO_CCW_ISC);
267
- kmem_cache_destroy(vfio_ccw_io_region);
268
- destroy_workqueue(vfio_ccw_work_q);
490
+ goto out_err;
269491 }
270492
493
+ return ret;
494
+
495
+out_err:
496
+ vfio_ccw_destroy_regions();
497
+ destroy_workqueue(vfio_ccw_work_q);
498
+ vfio_ccw_debug_exit();
271499 return ret;
272500 }
273501
....@@ -275,8 +503,9 @@
275503 {
276504 css_driver_unregister(&vfio_ccw_sch_driver);
277505 isc_unregister(VFIO_CCW_ISC);
278
- kmem_cache_destroy(vfio_ccw_io_region);
506
+ vfio_ccw_destroy_regions();
279507 destroy_workqueue(vfio_ccw_work_q);
508
+ vfio_ccw_debug_exit();
280509 }
281510 module_init(vfio_ccw_sch_init);
282511 module_exit(vfio_ccw_sch_exit);