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13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/device.h>
16#include <linux/slab.h>
17#include <linux/uuid.h>
18#include <linux/mdev.h>
19
20#include <asm/isc.h>
21
22#include "ioasm.h"
23#include "css.h"
24#include "vfio_ccw_private.h"
25
26struct workqueue_struct *vfio_ccw_work_q;
27static struct kmem_cache *vfio_ccw_io_region;
28static struct kmem_cache *vfio_ccw_cmd_region;
29
30debug_info_t *vfio_ccw_debug_msg_id;
31debug_info_t *vfio_ccw_debug_trace_id;
32
33
34
35
36int vfio_ccw_sch_quiesce(struct subchannel *sch)
37{
38 struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev);
39 DECLARE_COMPLETION_ONSTACK(completion);
40 int iretry, ret = 0;
41
42 spin_lock_irq(sch->lock);
43 if (!sch->schib.pmcw.ena)
44 goto out_unlock;
45 ret = cio_disable_subchannel(sch);
46 if (ret != -EBUSY)
47 goto out_unlock;
48
49 iretry = 255;
50 do {
51
52 ret = cio_cancel_halt_clear(sch, &iretry);
53
54 if (ret == -EIO) {
55 pr_err("vfio_ccw: could not quiesce subchannel 0.%x.%04x!\n",
56 sch->schid.ssid, sch->schid.sch_no);
57 break;
58 }
59
60
61
62
63
64 private->completion = &completion;
65 spin_unlock_irq(sch->lock);
66
67 if (ret == -EBUSY)
68 wait_for_completion_timeout(&completion, 3*HZ);
69
70 private->completion = NULL;
71 flush_workqueue(vfio_ccw_work_q);
72 spin_lock_irq(sch->lock);
73 ret = cio_disable_subchannel(sch);
74 } while (ret == -EBUSY);
75out_unlock:
76 private->state = VFIO_CCW_STATE_NOT_OPER;
77 spin_unlock_irq(sch->lock);
78 return ret;
79}
80
81static void vfio_ccw_sch_io_todo(struct work_struct *work)
82{
83 struct vfio_ccw_private *private;
84 struct irb *irb;
85 bool is_final;
86
87 private = container_of(work, struct vfio_ccw_private, io_work);
88 irb = &private->irb;
89
90 is_final = !(scsw_actl(&irb->scsw) &
91 (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT));
92 if (scsw_is_solicited(&irb->scsw)) {
93 cp_update_scsw(&private->cp, &irb->scsw);
94 if (is_final && private->state == VFIO_CCW_STATE_CP_PENDING)
95 cp_free(&private->cp);
96 }
97 mutex_lock(&private->io_mutex);
98 memcpy(private->io_region->irb_area, irb, sizeof(*irb));
99 mutex_unlock(&private->io_mutex);
100
101 if (private->mdev && is_final)
102 private->state = VFIO_CCW_STATE_IDLE;
103
104 if (private->io_trigger)
105 eventfd_signal(private->io_trigger, 1);
106}
107
108
109
110
111static void vfio_ccw_sch_irq(struct subchannel *sch)
112{
113 struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev);
114
115 inc_irq_stat(IRQIO_CIO);
116 vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_INTERRUPT);
117}
118
119static int vfio_ccw_sch_probe(struct subchannel *sch)
120{
121 struct pmcw *pmcw = &sch->schib.pmcw;
122 struct vfio_ccw_private *private;
123 int ret = -ENOMEM;
124
125 if (pmcw->qf) {
126 dev_warn(&sch->dev, "vfio: ccw: does not support QDIO: %s\n",
127 dev_name(&sch->dev));
128 return -ENODEV;
129 }
130
131 private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA);
132 if (!private)
133 return -ENOMEM;
134
135 private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct ccw1),
136 GFP_KERNEL);
137 if (!private->cp.guest_cp)
138 goto out_free;
139
140 private->io_region = kmem_cache_zalloc(vfio_ccw_io_region,
141 GFP_KERNEL | GFP_DMA);
142 if (!private->io_region)
143 goto out_free;
144
145 private->cmd_region = kmem_cache_zalloc(vfio_ccw_cmd_region,
146 GFP_KERNEL | GFP_DMA);
147 if (!private->cmd_region)
148 goto out_free;
149
150 private->sch = sch;
151 dev_set_drvdata(&sch->dev, private);
152 mutex_init(&private->io_mutex);
153
154 spin_lock_irq(sch->lock);
155 private->state = VFIO_CCW_STATE_NOT_OPER;
156 sch->isc = VFIO_CCW_ISC;
157 ret = cio_enable_subchannel(sch, (u32)(unsigned long)sch);
158 spin_unlock_irq(sch->lock);
159 if (ret)
160 goto out_free;
161
162 INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
163 atomic_set(&private->avail, 1);
164 private->state = VFIO_CCW_STATE_STANDBY;
165
166 ret = vfio_ccw_mdev_reg(sch);
167 if (ret)
168 goto out_disable;
169
170 VFIO_CCW_MSG_EVENT(4, "bound to subchannel %x.%x.%04x\n",
171 sch->schid.cssid, sch->schid.ssid,
172 sch->schid.sch_no);
173 return 0;
174
175out_disable:
176 cio_disable_subchannel(sch);
177out_free:
178 dev_set_drvdata(&sch->dev, NULL);
179 if (private->cmd_region)
180 kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
181 if (private->io_region)
182 kmem_cache_free(vfio_ccw_io_region, private->io_region);
183 kfree(private->cp.guest_cp);
184 kfree(private);
185 return ret;
186}
187
188static int vfio_ccw_sch_remove(struct subchannel *sch)
189{
190 struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev);
191
192 vfio_ccw_sch_quiesce(sch);
193
194 vfio_ccw_mdev_unreg(sch);
195
196 dev_set_drvdata(&sch->dev, NULL);
197
198 kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
199 kmem_cache_free(vfio_ccw_io_region, private->io_region);
200 kfree(private->cp.guest_cp);
201 kfree(private);
202
203 VFIO_CCW_MSG_EVENT(4, "unbound from subchannel %x.%x.%04x\n",
204 sch->schid.cssid, sch->schid.ssid,
205 sch->schid.sch_no);
206 return 0;
207}
208
209static void vfio_ccw_sch_shutdown(struct subchannel *sch)
210{
211 vfio_ccw_sch_quiesce(sch);
212}
213
214
215
216
217
218
219
220
221
222
223
224static int vfio_ccw_sch_event(struct subchannel *sch, int process)
225{
226 struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev);
227 unsigned long flags;
228 int rc = -EAGAIN;
229
230 spin_lock_irqsave(sch->lock, flags);
231 if (!device_is_registered(&sch->dev))
232 goto out_unlock;
233
234 if (work_pending(&sch->todo_work))
235 goto out_unlock;
236
237 if (cio_update_schib(sch)) {
238 vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_NOT_OPER);
239 rc = 0;
240 goto out_unlock;
241 }
242
243 private = dev_get_drvdata(&sch->dev);
244 if (private->state == VFIO_CCW_STATE_NOT_OPER) {
245 private->state = private->mdev ? VFIO_CCW_STATE_IDLE :
246 VFIO_CCW_STATE_STANDBY;
247 }
248 rc = 0;
249
250out_unlock:
251 spin_unlock_irqrestore(sch->lock, flags);
252
253 return rc;
254}
255
256static struct css_device_id vfio_ccw_sch_ids[] = {
257 { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
258 { },
259};
260MODULE_DEVICE_TABLE(css, vfio_ccw_sch_ids);
261
262static struct css_driver vfio_ccw_sch_driver = {
263 .drv = {
264 .name = "vfio_ccw",
265 .owner = THIS_MODULE,
266 },
267 .subchannel_type = vfio_ccw_sch_ids,
268 .irq = vfio_ccw_sch_irq,
269 .probe = vfio_ccw_sch_probe,
270 .remove = vfio_ccw_sch_remove,
271 .shutdown = vfio_ccw_sch_shutdown,
272 .sch_event = vfio_ccw_sch_event,
273};
274
275static int __init vfio_ccw_debug_init(void)
276{
277 vfio_ccw_debug_msg_id = debug_register("vfio_ccw_msg", 16, 1,
278 11 * sizeof(long));
279 if (!vfio_ccw_debug_msg_id)
280 goto out_unregister;
281 debug_register_view(vfio_ccw_debug_msg_id, &debug_sprintf_view);
282 debug_set_level(vfio_ccw_debug_msg_id, 2);
283 vfio_ccw_debug_trace_id = debug_register("vfio_ccw_trace", 16, 1, 16);
284 if (!vfio_ccw_debug_trace_id)
285 goto out_unregister;
286 debug_register_view(vfio_ccw_debug_trace_id, &debug_hex_ascii_view);
287 debug_set_level(vfio_ccw_debug_trace_id, 2);
288 return 0;
289
290out_unregister:
291 debug_unregister(vfio_ccw_debug_msg_id);
292 debug_unregister(vfio_ccw_debug_trace_id);
293 return -1;
294}
295
296static void vfio_ccw_debug_exit(void)
297{
298 debug_unregister(vfio_ccw_debug_msg_id);
299 debug_unregister(vfio_ccw_debug_trace_id);
300}
301
302static int __init vfio_ccw_sch_init(void)
303{
304 int ret;
305
306 ret = vfio_ccw_debug_init();
307 if (ret)
308 return ret;
309
310 vfio_ccw_work_q = create_singlethread_workqueue("vfio-ccw");
311 if (!vfio_ccw_work_q) {
312 ret = -ENOMEM;
313 goto out_err;
314 }
315
316 vfio_ccw_io_region = kmem_cache_create_usercopy("vfio_ccw_io_region",
317 sizeof(struct ccw_io_region), 0,
318 SLAB_ACCOUNT, 0,
319 sizeof(struct ccw_io_region), NULL);
320 if (!vfio_ccw_io_region) {
321 ret = -ENOMEM;
322 goto out_err;
323 }
324
325 vfio_ccw_cmd_region = kmem_cache_create_usercopy("vfio_ccw_cmd_region",
326 sizeof(struct ccw_cmd_region), 0,
327 SLAB_ACCOUNT, 0,
328 sizeof(struct ccw_cmd_region), NULL);
329 if (!vfio_ccw_cmd_region) {
330 ret = -ENOMEM;
331 goto out_err;
332 }
333
334 isc_register(VFIO_CCW_ISC);
335 ret = css_driver_register(&vfio_ccw_sch_driver);
336 if (ret) {
337 isc_unregister(VFIO_CCW_ISC);
338 goto out_err;
339 }
340
341 return ret;
342
343out_err:
344 kmem_cache_destroy(vfio_ccw_cmd_region);
345 kmem_cache_destroy(vfio_ccw_io_region);
346 destroy_workqueue(vfio_ccw_work_q);
347 vfio_ccw_debug_exit();
348 return ret;
349}
350
351static void __exit vfio_ccw_sch_exit(void)
352{
353 css_driver_unregister(&vfio_ccw_sch_driver);
354 isc_unregister(VFIO_CCW_ISC);
355 kmem_cache_destroy(vfio_ccw_io_region);
356 kmem_cache_destroy(vfio_ccw_cmd_region);
357 destroy_workqueue(vfio_ccw_work_q);
358 vfio_ccw_debug_exit();
359}
360module_init(vfio_ccw_sch_init);
361module_exit(vfio_ccw_sch_exit);
362
363MODULE_LICENSE("GPL v2");
364
