Commit | Line | Data |
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724117b7 | 1 | // SPDX-License-Identifier: GPL-2.0 |
eadb86ab SO |
2 | /* |
3 | * Driver for s390 eadm subchannels | |
4 | * | |
5 | * Copyright IBM Corp. 2012 | |
6 | * Author(s): Sebastian Ott <sebott@linux.vnet.ibm.com> | |
7 | */ | |
8 | ||
2e73c2cf | 9 | #include <linux/kernel_stat.h> |
6aa2677a | 10 | #include <linux/completion.h> |
eadb86ab SO |
11 | #include <linux/workqueue.h> |
12 | #include <linux/spinlock.h> | |
13 | #include <linux/device.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/timer.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/list.h> | |
18 | ||
19 | #include <asm/css_chars.h> | |
20 | #include <asm/debug.h> | |
21 | #include <asm/isc.h> | |
22 | #include <asm/cio.h> | |
23 | #include <asm/scsw.h> | |
24 | #include <asm/eadm.h> | |
25 | ||
26 | #include "eadm_sch.h" | |
27 | #include "ioasm.h" | |
28 | #include "cio.h" | |
29 | #include "css.h" | |
30 | #include "orb.h" | |
31 | ||
32 | MODULE_DESCRIPTION("driver for s390 eadm subchannels"); | |
33 | MODULE_LICENSE("GPL"); | |
34 | ||
e2578b82 | 35 | #define EADM_TIMEOUT (7 * HZ) |
eadb86ab SO |
36 | static DEFINE_SPINLOCK(list_lock); |
37 | static LIST_HEAD(eadm_list); | |
38 | ||
39 | static debug_info_t *eadm_debug; | |
40 | ||
41 | #define EADM_LOG(imp, txt) do { \ | |
42 | debug_text_event(eadm_debug, imp, txt); \ | |
43 | } while (0) | |
44 | ||
45 | static void EADM_LOG_HEX(int level, void *data, int length) | |
46 | { | |
94158e54 | 47 | debug_event(eadm_debug, level, data, length); |
eadb86ab SO |
48 | } |
49 | ||
50 | static void orb_init(union orb *orb) | |
51 | { | |
52 | memset(orb, 0, sizeof(union orb)); | |
53 | orb->eadm.compat1 = 1; | |
54 | orb->eadm.compat2 = 1; | |
55 | orb->eadm.fmt = 1; | |
56 | orb->eadm.x = 1; | |
57 | } | |
58 | ||
59 | static int eadm_subchannel_start(struct subchannel *sch, struct aob *aob) | |
60 | { | |
61 | union orb *orb = &get_eadm_private(sch)->orb; | |
62 | int cc; | |
63 | ||
64 | orb_init(orb); | |
65 | orb->eadm.aob = (u32)__pa(aob); | |
66 | orb->eadm.intparm = (u32)(addr_t)sch; | |
67 | orb->eadm.key = PAGE_DEFAULT_KEY >> 4; | |
68 | ||
69 | EADM_LOG(6, "start"); | |
70 | EADM_LOG_HEX(6, &sch->schid, sizeof(sch->schid)); | |
71 | ||
72 | cc = ssch(sch->schid, orb); | |
73 | switch (cc) { | |
74 | case 0: | |
75 | sch->schib.scsw.eadm.actl |= SCSW_ACTL_START_PEND; | |
76 | break; | |
77 | case 1: /* status pending */ | |
78 | case 2: /* busy */ | |
79 | return -EBUSY; | |
80 | case 3: /* not operational */ | |
81 | return -ENODEV; | |
82 | } | |
83 | return 0; | |
84 | } | |
85 | ||
86 | static int eadm_subchannel_clear(struct subchannel *sch) | |
87 | { | |
88 | int cc; | |
89 | ||
90 | cc = csch(sch->schid); | |
91 | if (cc) | |
92 | return -ENODEV; | |
93 | ||
94 | sch->schib.scsw.eadm.actl |= SCSW_ACTL_CLEAR_PEND; | |
95 | return 0; | |
96 | } | |
97 | ||
846d0c6f | 98 | static void eadm_subchannel_timeout(struct timer_list *t) |
eadb86ab | 99 | { |
846d0c6f KC |
100 | struct eadm_private *private = from_timer(private, t, timer); |
101 | struct subchannel *sch = private->sch; | |
eadb86ab SO |
102 | |
103 | spin_lock_irq(sch->lock); | |
104 | EADM_LOG(1, "timeout"); | |
105 | EADM_LOG_HEX(1, &sch->schid, sizeof(sch->schid)); | |
106 | if (eadm_subchannel_clear(sch)) | |
107 | EADM_LOG(0, "clear failed"); | |
108 | spin_unlock_irq(sch->lock); | |
109 | } | |
110 | ||
111 | static void eadm_subchannel_set_timeout(struct subchannel *sch, int expires) | |
112 | { | |
113 | struct eadm_private *private = get_eadm_private(sch); | |
114 | ||
115 | if (expires == 0) { | |
116 | del_timer(&private->timer); | |
117 | return; | |
118 | } | |
119 | if (timer_pending(&private->timer)) { | |
120 | if (mod_timer(&private->timer, jiffies + expires)) | |
121 | return; | |
122 | } | |
eadb86ab SO |
123 | private->timer.expires = jiffies + expires; |
124 | add_timer(&private->timer); | |
125 | } | |
126 | ||
127 | static void eadm_subchannel_irq(struct subchannel *sch) | |
128 | { | |
129 | struct eadm_private *private = get_eadm_private(sch); | |
130 | struct eadm_scsw *scsw = &sch->schib.scsw.eadm; | |
0bf7fcf1 | 131 | struct irb *irb = this_cpu_ptr(&cio_irb); |
2a842aca | 132 | blk_status_t error = BLK_STS_OK; |
eadb86ab SO |
133 | |
134 | EADM_LOG(6, "irq"); | |
135 | EADM_LOG_HEX(6, irb, sizeof(*irb)); | |
136 | ||
420f42ec | 137 | inc_irq_stat(IRQIO_ADM); |
2e73c2cf | 138 | |
eadb86ab SO |
139 | if ((scsw->stctl & (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) |
140 | && scsw->eswf == 1 && irb->esw.eadm.erw.r) | |
2a842aca | 141 | error = BLK_STS_IOERR; |
eadb86ab SO |
142 | |
143 | if (scsw->fctl & SCSW_FCTL_CLEAR_FUNC) | |
2a842aca | 144 | error = BLK_STS_TIMEOUT; |
eadb86ab SO |
145 | |
146 | eadm_subchannel_set_timeout(sch, 0); | |
147 | ||
148 | if (private->state != EADM_BUSY) { | |
149 | EADM_LOG(1, "irq unsol"); | |
150 | EADM_LOG_HEX(1, irb, sizeof(*irb)); | |
151 | private->state = EADM_NOT_OPER; | |
152 | css_sched_sch_todo(sch, SCH_TODO_EVAL); | |
153 | return; | |
154 | } | |
155 | scm_irq_handler((struct aob *)(unsigned long)scsw->aob, error); | |
156 | private->state = EADM_IDLE; | |
6aa2677a SO |
157 | |
158 | if (private->completion) | |
159 | complete(private->completion); | |
eadb86ab SO |
160 | } |
161 | ||
162 | static struct subchannel *eadm_get_idle_sch(void) | |
163 | { | |
164 | struct eadm_private *private; | |
165 | struct subchannel *sch; | |
166 | unsigned long flags; | |
167 | ||
168 | spin_lock_irqsave(&list_lock, flags); | |
169 | list_for_each_entry(private, &eadm_list, head) { | |
170 | sch = private->sch; | |
171 | spin_lock(sch->lock); | |
172 | if (private->state == EADM_IDLE) { | |
173 | private->state = EADM_BUSY; | |
174 | list_move_tail(&private->head, &eadm_list); | |
175 | spin_unlock(sch->lock); | |
176 | spin_unlock_irqrestore(&list_lock, flags); | |
177 | ||
178 | return sch; | |
179 | } | |
180 | spin_unlock(sch->lock); | |
181 | } | |
182 | spin_unlock_irqrestore(&list_lock, flags); | |
183 | ||
184 | return NULL; | |
185 | } | |
186 | ||
605c3698 | 187 | int eadm_start_aob(struct aob *aob) |
eadb86ab SO |
188 | { |
189 | struct eadm_private *private; | |
190 | struct subchannel *sch; | |
191 | unsigned long flags; | |
192 | int ret; | |
193 | ||
194 | sch = eadm_get_idle_sch(); | |
195 | if (!sch) | |
196 | return -EBUSY; | |
197 | ||
198 | spin_lock_irqsave(sch->lock, flags); | |
199 | eadm_subchannel_set_timeout(sch, EADM_TIMEOUT); | |
200 | ret = eadm_subchannel_start(sch, aob); | |
201 | if (!ret) | |
202 | goto out_unlock; | |
203 | ||
204 | /* Handle start subchannel failure. */ | |
205 | eadm_subchannel_set_timeout(sch, 0); | |
206 | private = get_eadm_private(sch); | |
207 | private->state = EADM_NOT_OPER; | |
208 | css_sched_sch_todo(sch, SCH_TODO_EVAL); | |
209 | ||
210 | out_unlock: | |
211 | spin_unlock_irqrestore(sch->lock, flags); | |
212 | ||
213 | return ret; | |
214 | } | |
605c3698 | 215 | EXPORT_SYMBOL_GPL(eadm_start_aob); |
eadb86ab SO |
216 | |
217 | static int eadm_subchannel_probe(struct subchannel *sch) | |
218 | { | |
219 | struct eadm_private *private; | |
220 | int ret; | |
221 | ||
222 | private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA); | |
223 | if (!private) | |
224 | return -ENOMEM; | |
225 | ||
226 | INIT_LIST_HEAD(&private->head); | |
846d0c6f | 227 | timer_setup(&private->timer, eadm_subchannel_timeout, 0); |
eadb86ab SO |
228 | |
229 | spin_lock_irq(sch->lock); | |
230 | set_eadm_private(sch, private); | |
231 | private->state = EADM_IDLE; | |
232 | private->sch = sch; | |
233 | sch->isc = EADM_SCH_ISC; | |
234 | ret = cio_enable_subchannel(sch, (u32)(unsigned long)sch); | |
235 | if (ret) { | |
236 | set_eadm_private(sch, NULL); | |
237 | spin_unlock_irq(sch->lock); | |
238 | kfree(private); | |
239 | goto out; | |
240 | } | |
241 | spin_unlock_irq(sch->lock); | |
242 | ||
243 | spin_lock_irq(&list_lock); | |
244 | list_add(&private->head, &eadm_list); | |
245 | spin_unlock_irq(&list_lock); | |
246 | ||
247 | if (dev_get_uevent_suppress(&sch->dev)) { | |
248 | dev_set_uevent_suppress(&sch->dev, 0); | |
249 | kobject_uevent(&sch->dev.kobj, KOBJ_ADD); | |
250 | } | |
251 | out: | |
252 | return ret; | |
253 | } | |
254 | ||
255 | static void eadm_quiesce(struct subchannel *sch) | |
256 | { | |
6aa2677a SO |
257 | struct eadm_private *private = get_eadm_private(sch); |
258 | DECLARE_COMPLETION_ONSTACK(completion); | |
eadb86ab SO |
259 | int ret; |
260 | ||
6aa2677a SO |
261 | spin_lock_irq(sch->lock); |
262 | if (private->state != EADM_BUSY) | |
263 | goto disable; | |
264 | ||
265 | if (eadm_subchannel_clear(sch)) | |
266 | goto disable; | |
267 | ||
268 | private->completion = &completion; | |
269 | spin_unlock_irq(sch->lock); | |
270 | ||
271 | wait_for_completion_io(&completion); | |
272 | ||
273 | spin_lock_irq(sch->lock); | |
274 | private->completion = NULL; | |
275 | ||
276 | disable: | |
277 | eadm_subchannel_set_timeout(sch, 0); | |
eadb86ab | 278 | do { |
eadb86ab | 279 | ret = cio_disable_subchannel(sch); |
eadb86ab | 280 | } while (ret == -EBUSY); |
6aa2677a SO |
281 | |
282 | spin_unlock_irq(sch->lock); | |
eadb86ab SO |
283 | } |
284 | ||
285 | static int eadm_subchannel_remove(struct subchannel *sch) | |
286 | { | |
287 | struct eadm_private *private = get_eadm_private(sch); | |
288 | ||
289 | spin_lock_irq(&list_lock); | |
290 | list_del(&private->head); | |
291 | spin_unlock_irq(&list_lock); | |
292 | ||
293 | eadm_quiesce(sch); | |
294 | ||
295 | spin_lock_irq(sch->lock); | |
296 | set_eadm_private(sch, NULL); | |
297 | spin_unlock_irq(sch->lock); | |
298 | ||
299 | kfree(private); | |
300 | ||
301 | return 0; | |
302 | } | |
303 | ||
304 | static void eadm_subchannel_shutdown(struct subchannel *sch) | |
305 | { | |
306 | eadm_quiesce(sch); | |
307 | } | |
308 | ||
309 | static int eadm_subchannel_freeze(struct subchannel *sch) | |
310 | { | |
311 | return cio_disable_subchannel(sch); | |
312 | } | |
313 | ||
314 | static int eadm_subchannel_restore(struct subchannel *sch) | |
315 | { | |
316 | return cio_enable_subchannel(sch, (u32)(unsigned long)sch); | |
317 | } | |
318 | ||
319 | /** | |
320 | * eadm_subchannel_sch_event - process subchannel event | |
321 | * @sch: subchannel | |
322 | * @process: non-zero if function is called in process context | |
323 | * | |
324 | * An unspecified event occurred for this subchannel. Adjust data according | |
325 | * to the current operational state of the subchannel. Return zero when the | |
326 | * event has been handled sufficiently or -EAGAIN when this function should | |
327 | * be called again in process context. | |
328 | */ | |
329 | static int eadm_subchannel_sch_event(struct subchannel *sch, int process) | |
330 | { | |
331 | struct eadm_private *private; | |
332 | unsigned long flags; | |
eadb86ab SO |
333 | |
334 | spin_lock_irqsave(sch->lock, flags); | |
335 | if (!device_is_registered(&sch->dev)) | |
336 | goto out_unlock; | |
337 | ||
338 | if (work_pending(&sch->todo_work)) | |
339 | goto out_unlock; | |
340 | ||
341 | if (cio_update_schib(sch)) { | |
342 | css_sched_sch_todo(sch, SCH_TODO_UNREG); | |
343 | goto out_unlock; | |
344 | } | |
345 | private = get_eadm_private(sch); | |
346 | if (private->state == EADM_NOT_OPER) | |
347 | private->state = EADM_IDLE; | |
348 | ||
349 | out_unlock: | |
350 | spin_unlock_irqrestore(sch->lock, flags); | |
351 | ||
b2f4de8b | 352 | return 0; |
eadb86ab SO |
353 | } |
354 | ||
355 | static struct css_device_id eadm_subchannel_ids[] = { | |
356 | { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_ADM, }, | |
357 | { /* end of list */ }, | |
358 | }; | |
359 | MODULE_DEVICE_TABLE(css, eadm_subchannel_ids); | |
360 | ||
361 | static struct css_driver eadm_subchannel_driver = { | |
362 | .drv = { | |
363 | .name = "eadm_subchannel", | |
364 | .owner = THIS_MODULE, | |
365 | }, | |
366 | .subchannel_type = eadm_subchannel_ids, | |
367 | .irq = eadm_subchannel_irq, | |
368 | .probe = eadm_subchannel_probe, | |
369 | .remove = eadm_subchannel_remove, | |
370 | .shutdown = eadm_subchannel_shutdown, | |
371 | .sch_event = eadm_subchannel_sch_event, | |
372 | .freeze = eadm_subchannel_freeze, | |
373 | .thaw = eadm_subchannel_restore, | |
374 | .restore = eadm_subchannel_restore, | |
375 | }; | |
376 | ||
eadb86ab SO |
377 | static int __init eadm_sch_init(void) |
378 | { | |
379 | int ret; | |
380 | ||
381 | if (!css_general_characteristics.eadm) | |
382 | return -ENXIO; | |
383 | ||
384 | eadm_debug = debug_register("eadm_log", 16, 1, 16); | |
385 | if (!eadm_debug) | |
386 | return -ENOMEM; | |
387 | ||
388 | debug_register_view(eadm_debug, &debug_hex_ascii_view); | |
389 | debug_set_level(eadm_debug, 2); | |
390 | ||
391 | isc_register(EADM_SCH_ISC); | |
392 | ret = css_driver_register(&eadm_subchannel_driver); | |
393 | if (ret) | |
394 | goto cleanup; | |
395 | ||
eadb86ab SO |
396 | return ret; |
397 | ||
398 | cleanup: | |
399 | isc_unregister(EADM_SCH_ISC); | |
400 | debug_unregister(eadm_debug); | |
401 | return ret; | |
402 | } | |
403 | ||
404 | static void __exit eadm_sch_exit(void) | |
405 | { | |
eadb86ab SO |
406 | css_driver_unregister(&eadm_subchannel_driver); |
407 | isc_unregister(EADM_SCH_ISC); | |
408 | debug_unregister(eadm_debug); | |
409 | } | |
410 | module_init(eadm_sch_init); | |
411 | module_exit(eadm_sch_exit); |