1/*
2 * Copyright IBM Corp. 2002, 2009
3 *
4 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
5 *	      Cornelia Huck (cornelia.huck@de.ibm.com)
6 */
7#include <linux/module.h>
8#include <linux/init.h>
9#include <linux/errno.h>
10#include <linux/slab.h>
11#include <linux/list.h>
12#include <linux/device.h>
13#include <linux/delay.h>
14#include <linux/completion.h>
15
16#include <asm/ccwdev.h>
17#include <asm/idals.h>
18#include <asm/chpid.h>
19#include <asm/fcx.h>
20
21#include "cio.h"
22#include "cio_debug.h"
23#include "css.h"
24#include "chsc.h"
25#include "device.h"
26#include "chp.h"
27
28/**
29 * ccw_device_set_options_mask() - set some options and unset the rest
30 * @cdev: device for which the options are to be set
31 * @flags: options to be set
32 *
33 * All flags specified in @flags are set, all flags not specified in @flags
34 * are cleared.
35 * Returns:
36 *   %0 on success, -%EINVAL on an invalid flag combination.
37 */
38int ccw_device_set_options_mask(struct ccw_device *cdev, unsigned long flags)
39{
40       /*
41	* The flag usage is mutal exclusive ...
42	*/
43	if ((flags & CCWDEV_EARLY_NOTIFICATION) &&
44	    (flags & CCWDEV_REPORT_ALL))
45		return -EINVAL;
46	cdev->private->options.fast = (flags & CCWDEV_EARLY_NOTIFICATION) != 0;
47	cdev->private->options.repall = (flags & CCWDEV_REPORT_ALL) != 0;
48	cdev->private->options.pgroup = (flags & CCWDEV_DO_PATHGROUP) != 0;
49	cdev->private->options.force = (flags & CCWDEV_ALLOW_FORCE) != 0;
50	cdev->private->options.mpath = (flags & CCWDEV_DO_MULTIPATH) != 0;
51	return 0;
52}
53
54/**
55 * ccw_device_set_options() - set some options
56 * @cdev: device for which the options are to be set
57 * @flags: options to be set
58 *
59 * All flags specified in @flags are set, the remainder is left untouched.
60 * Returns:
61 *   %0 on success, -%EINVAL if an invalid flag combination would ensue.
62 */
63int ccw_device_set_options(struct ccw_device *cdev, unsigned long flags)
64{
65       /*
66	* The flag usage is mutal exclusive ...
67	*/
68	if (((flags & CCWDEV_EARLY_NOTIFICATION) &&
69	    (flags & CCWDEV_REPORT_ALL)) ||
70	    ((flags & CCWDEV_EARLY_NOTIFICATION) &&
71	     cdev->private->options.repall) ||
72	    ((flags & CCWDEV_REPORT_ALL) &&
73	     cdev->private->options.fast))
74		return -EINVAL;
75	cdev->private->options.fast |= (flags & CCWDEV_EARLY_NOTIFICATION) != 0;
76	cdev->private->options.repall |= (flags & CCWDEV_REPORT_ALL) != 0;
77	cdev->private->options.pgroup |= (flags & CCWDEV_DO_PATHGROUP) != 0;
78	cdev->private->options.force |= (flags & CCWDEV_ALLOW_FORCE) != 0;
79	cdev->private->options.mpath |= (flags & CCWDEV_DO_MULTIPATH) != 0;
80	return 0;
81}
82
83/**
84 * ccw_device_clear_options() - clear some options
85 * @cdev: device for which the options are to be cleared
86 * @flags: options to be cleared
87 *
88 * All flags specified in @flags are cleared, the remainder is left untouched.
89 */
90void ccw_device_clear_options(struct ccw_device *cdev, unsigned long flags)
91{
92	cdev->private->options.fast &= (flags & CCWDEV_EARLY_NOTIFICATION) == 0;
93	cdev->private->options.repall &= (flags & CCWDEV_REPORT_ALL) == 0;
94	cdev->private->options.pgroup &= (flags & CCWDEV_DO_PATHGROUP) == 0;
95	cdev->private->options.force &= (flags & CCWDEV_ALLOW_FORCE) == 0;
96	cdev->private->options.mpath &= (flags & CCWDEV_DO_MULTIPATH) == 0;
97}
98
99/**
100 * ccw_device_is_pathgroup - determine if paths to this device are grouped
101 * @cdev: ccw device
102 *
103 * Return non-zero if there is a path group, zero otherwise.
104 */
105int ccw_device_is_pathgroup(struct ccw_device *cdev)
106{
107	return cdev->private->flags.pgroup;
108}
109EXPORT_SYMBOL(ccw_device_is_pathgroup);
110
111/**
112 * ccw_device_is_multipath - determine if device is operating in multipath mode
113 * @cdev: ccw device
114 *
115 * Return non-zero if device is operating in multipath mode, zero otherwise.
116 */
117int ccw_device_is_multipath(struct ccw_device *cdev)
118{
119	return cdev->private->flags.mpath;
120}
121EXPORT_SYMBOL(ccw_device_is_multipath);
122
123/**
124 * ccw_device_clear() - terminate I/O request processing
125 * @cdev: target ccw device
126 * @intparm: interruption parameter; value is only used if no I/O is
127 *	     outstanding, otherwise the intparm associated with the I/O request
128 *	     is returned
129 *
130 * ccw_device_clear() calls csch on @cdev's subchannel.
131 * Returns:
132 *  %0 on success,
133 *  -%ENODEV on device not operational,
134 *  -%EINVAL on invalid device state.
135 * Context:
136 *  Interrupts disabled, ccw device lock held
137 */
138int ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
139{
140	struct subchannel *sch;
141	int ret;
142
143	if (!cdev || !cdev->dev.parent)
144		return -ENODEV;
145	sch = to_subchannel(cdev->dev.parent);
146	if (!sch->schib.pmcw.ena)
147		return -EINVAL;
148	if (cdev->private->state == DEV_STATE_NOT_OPER)
149		return -ENODEV;
150	if (cdev->private->state != DEV_STATE_ONLINE &&
151	    cdev->private->state != DEV_STATE_W4SENSE)
152		return -EINVAL;
153
154	ret = cio_clear(sch);
155	if (ret == 0)
156		cdev->private->intparm = intparm;
157	return ret;
158}
159
160/**
161 * ccw_device_start_key() - start a s390 channel program with key
162 * @cdev: target ccw device
163 * @cpa: logical start address of channel program
164 * @intparm: user specific interruption parameter; will be presented back to
165 *	     @cdev's interrupt handler. Allows a device driver to associate
166 *	     the interrupt with a particular I/O request.
167 * @lpm: defines the channel path to be used for a specific I/O request. A
168 *	 value of 0 will make cio use the opm.
169 * @key: storage key to be used for the I/O
170 * @flags: additional flags; defines the action to be performed for I/O
171 *	   processing.
172 *
173 * Start a S/390 channel program. When the interrupt arrives, the
174 * IRQ handler is called, either immediately, delayed (dev-end missing,
175 * or sense required) or never (no IRQ handler registered).
176 * Returns:
177 *  %0, if the operation was successful;
178 *  -%EBUSY, if the device is busy, or status pending;
179 *  -%EACCES, if no path specified in @lpm is operational;
180 *  -%ENODEV, if the device is not operational.
181 * Context:
182 *  Interrupts disabled, ccw device lock held
183 */
184int ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa,
185			 unsigned long intparm, __u8 lpm, __u8 key,
186			 unsigned long flags)
187{
188	struct subchannel *sch;
189	int ret;
190
191	if (!cdev || !cdev->dev.parent)
192		return -ENODEV;
193	sch = to_subchannel(cdev->dev.parent);
194	if (!sch->schib.pmcw.ena)
195		return -EINVAL;
196	if (cdev->private->state == DEV_STATE_NOT_OPER)
197		return -ENODEV;
198	if (cdev->private->state == DEV_STATE_VERIFY) {
199		/* Remember to fake irb when finished. */
200		if (!cdev->private->flags.fake_irb) {
201			cdev->private->flags.fake_irb = FAKE_CMD_IRB;
202			cdev->private->intparm = intparm;
203			return 0;
204		} else
205			/* There's already a fake I/O around. */
206			return -EBUSY;
207	}
208	if (cdev->private->state != DEV_STATE_ONLINE ||
209	    ((sch->schib.scsw.cmd.stctl & SCSW_STCTL_PRIM_STATUS) &&
210	     !(sch->schib.scsw.cmd.stctl & SCSW_STCTL_SEC_STATUS)) ||
211	    cdev->private->flags.doverify)
212		return -EBUSY;
213	ret = cio_set_options (sch, flags);
214	if (ret)
215		return ret;
216	/* Adjust requested path mask to exclude unusable paths. */
217	if (lpm) {
218		lpm &= sch->lpm;
219		if (lpm == 0)
220			return -EACCES;
221	}
222	ret = cio_start_key (sch, cpa, lpm, key);
223	switch (ret) {
224	case 0:
225		cdev->private->intparm = intparm;
226		break;
227	case -EACCES:
228	case -ENODEV:
229		dev_fsm_event(cdev, DEV_EVENT_VERIFY);
230		break;
231	}
232	return ret;
233}
234
235/**
236 * ccw_device_start_timeout_key() - start a s390 channel program with timeout and key
237 * @cdev: target ccw device
238 * @cpa: logical start address of channel program
239 * @intparm: user specific interruption parameter; will be presented back to
240 *	     @cdev's interrupt handler. Allows a device driver to associate
241 *	     the interrupt with a particular I/O request.
242 * @lpm: defines the channel path to be used for a specific I/O request. A
243 *	 value of 0 will make cio use the opm.
244 * @key: storage key to be used for the I/O
245 * @flags: additional flags; defines the action to be performed for I/O
246 *	   processing.
247 * @expires: timeout value in jiffies
248 *
249 * Start a S/390 channel program. When the interrupt arrives, the
250 * IRQ handler is called, either immediately, delayed (dev-end missing,
251 * or sense required) or never (no IRQ handler registered).
252 * This function notifies the device driver if the channel program has not
253 * completed during the time specified by @expires. If a timeout occurs, the
254 * channel program is terminated via xsch, hsch or csch, and the device's
255 * interrupt handler will be called with an irb containing ERR_PTR(-%ETIMEDOUT).
256 * Returns:
257 *  %0, if the operation was successful;
258 *  -%EBUSY, if the device is busy, or status pending;
259 *  -%EACCES, if no path specified in @lpm is operational;
260 *  -%ENODEV, if the device is not operational.
261 * Context:
262 *  Interrupts disabled, ccw device lock held
263 */
264int ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa,
265				 unsigned long intparm, __u8 lpm, __u8 key,
266				 unsigned long flags, int expires)
267{
268	int ret;
269
270	if (!cdev)
271		return -ENODEV;
272	ccw_device_set_timeout(cdev, expires);
273	ret = ccw_device_start_key(cdev, cpa, intparm, lpm, key, flags);
274	if (ret != 0)
275		ccw_device_set_timeout(cdev, 0);
276	return ret;
277}
278
279/**
280 * ccw_device_start() - start a s390 channel program
281 * @cdev: target ccw device
282 * @cpa: logical start address of channel program
283 * @intparm: user specific interruption parameter; will be presented back to
284 *	     @cdev's interrupt handler. Allows a device driver to associate
285 *	     the interrupt with a particular I/O request.
286 * @lpm: defines the channel path to be used for a specific I/O request. A
287 *	 value of 0 will make cio use the opm.
288 * @flags: additional flags; defines the action to be performed for I/O
289 *	   processing.
290 *
291 * Start a S/390 channel program. When the interrupt arrives, the
292 * IRQ handler is called, either immediately, delayed (dev-end missing,
293 * or sense required) or never (no IRQ handler registered).
294 * Returns:
295 *  %0, if the operation was successful;
296 *  -%EBUSY, if the device is busy, or status pending;
297 *  -%EACCES, if no path specified in @lpm is operational;
298 *  -%ENODEV, if the device is not operational.
299 * Context:
300 *  Interrupts disabled, ccw device lock held
301 */
302int ccw_device_start(struct ccw_device *cdev, struct ccw1 *cpa,
303		     unsigned long intparm, __u8 lpm, unsigned long flags)
304{
305	return ccw_device_start_key(cdev, cpa, intparm, lpm,
306				    PAGE_DEFAULT_KEY, flags);
307}
308
309/**
310 * ccw_device_start_timeout() - start a s390 channel program with timeout
311 * @cdev: target ccw device
312 * @cpa: logical start address of channel program
313 * @intparm: user specific interruption parameter; will be presented back to
314 *	     @cdev's interrupt handler. Allows a device driver to associate
315 *	     the interrupt with a particular I/O request.
316 * @lpm: defines the channel path to be used for a specific I/O request. A
317 *	 value of 0 will make cio use the opm.
318 * @flags: additional flags; defines the action to be performed for I/O
319 *	   processing.
320 * @expires: timeout value in jiffies
321 *
322 * Start a S/390 channel program. When the interrupt arrives, the
323 * IRQ handler is called, either immediately, delayed (dev-end missing,
324 * or sense required) or never (no IRQ handler registered).
325 * This function notifies the device driver if the channel program has not
326 * completed during the time specified by @expires. If a timeout occurs, the
327 * channel program is terminated via xsch, hsch or csch, and the device's
328 * interrupt handler will be called with an irb containing ERR_PTR(-%ETIMEDOUT).
329 * Returns:
330 *  %0, if the operation was successful;
331 *  -%EBUSY, if the device is busy, or status pending;
332 *  -%EACCES, if no path specified in @lpm is operational;
333 *  -%ENODEV, if the device is not operational.
334 * Context:
335 *  Interrupts disabled, ccw device lock held
336 */
337int ccw_device_start_timeout(struct ccw_device *cdev, struct ccw1 *cpa,
338			     unsigned long intparm, __u8 lpm,
339			     unsigned long flags, int expires)
340{
341	return ccw_device_start_timeout_key(cdev, cpa, intparm, lpm,
342					    PAGE_DEFAULT_KEY, flags,
343					    expires);
344}
345
346
347/**
348 * ccw_device_halt() - halt I/O request processing
349 * @cdev: target ccw device
350 * @intparm: interruption parameter; value is only used if no I/O is
351 *	     outstanding, otherwise the intparm associated with the I/O request
352 *	     is returned
353 *
354 * ccw_device_halt() calls hsch on @cdev's subchannel.
355 * Returns:
356 *  %0 on success,
357 *  -%ENODEV on device not operational,
358 *  -%EINVAL on invalid device state,
359 *  -%EBUSY on device busy or interrupt pending.
360 * Context:
361 *  Interrupts disabled, ccw device lock held
362 */
363int ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
364{
365	struct subchannel *sch;
366	int ret;
367
368	if (!cdev || !cdev->dev.parent)
369		return -ENODEV;
370	sch = to_subchannel(cdev->dev.parent);
371	if (!sch->schib.pmcw.ena)
372		return -EINVAL;
373	if (cdev->private->state == DEV_STATE_NOT_OPER)
374		return -ENODEV;
375	if (cdev->private->state != DEV_STATE_ONLINE &&
376	    cdev->private->state != DEV_STATE_W4SENSE)
377		return -EINVAL;
378
379	ret = cio_halt(sch);
380	if (ret == 0)
381		cdev->private->intparm = intparm;
382	return ret;
383}
384
385/**
386 * ccw_device_resume() - resume channel program execution
387 * @cdev: target ccw device
388 *
389 * ccw_device_resume() calls rsch on @cdev's subchannel.
390 * Returns:
391 *  %0 on success,
392 *  -%ENODEV on device not operational,
393 *  -%EINVAL on invalid device state,
394 *  -%EBUSY on device busy or interrupt pending.
395 * Context:
396 *  Interrupts disabled, ccw device lock held
397 */
398int ccw_device_resume(struct ccw_device *cdev)
399{
400	struct subchannel *sch;
401
402	if (!cdev || !cdev->dev.parent)
403		return -ENODEV;
404	sch = to_subchannel(cdev->dev.parent);
405	if (!sch->schib.pmcw.ena)
406		return -EINVAL;
407	if (cdev->private->state == DEV_STATE_NOT_OPER)
408		return -ENODEV;
409	if (cdev->private->state != DEV_STATE_ONLINE ||
410	    !(sch->schib.scsw.cmd.actl & SCSW_ACTL_SUSPENDED))
411		return -EINVAL;
412	return cio_resume(sch);
413}
414
415/*
416 * Pass interrupt to device driver.
417 */
418int
419ccw_device_call_handler(struct ccw_device *cdev)
420{
421	unsigned int stctl;
422	int ending_status;
423
424	/*
425	 * we allow for the device action handler if .
426	 *  - we received ending status
427	 *  - the action handler requested to see all interrupts
428	 *  - we received an intermediate status
429	 *  - fast notification was requested (primary status)
430	 *  - unsolicited interrupts
431	 */
432	stctl = scsw_stctl(&cdev->private->irb.scsw);
433	ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
434		(stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
435		(stctl == SCSW_STCTL_STATUS_PEND);
436	if (!ending_status &&
437	    !cdev->private->options.repall &&
438	    !(stctl & SCSW_STCTL_INTER_STATUS) &&
439	    !(cdev->private->options.fast &&
440	      (stctl & SCSW_STCTL_PRIM_STATUS)))
441		return 0;
442
443	/* Clear pending timers for device driver initiated I/O. */
444	if (ending_status)
445		ccw_device_set_timeout(cdev, 0);
446	/*
447	 * Now we are ready to call the device driver interrupt handler.
448	 */
449	if (cdev->handler)
450		cdev->handler(cdev, cdev->private->intparm,
451			      &cdev->private->irb);
452
453	/*
454	 * Clear the old and now useless interrupt response block.
455	 */
456	memset(&cdev->private->irb, 0, sizeof(struct irb));
457
458	return 1;
459}
460
461/**
462 * ccw_device_get_ciw() - Search for CIW command in extended sense data.
463 * @cdev: ccw device to inspect
464 * @ct: command type to look for
465 *
466 * During SenseID, command information words (CIWs) describing special
467 * commands available to the device may have been stored in the extended
468 * sense data. This function searches for CIWs of a specified command
469 * type in the extended sense data.
470 * Returns:
471 *  %NULL if no extended sense data has been stored or if no CIW of the
472 *  specified command type could be found,
473 *  else a pointer to the CIW of the specified command type.
474 */
475struct ciw *ccw_device_get_ciw(struct ccw_device *cdev, __u32 ct)
476{
477	int ciw_cnt;
478
479	if (cdev->private->flags.esid == 0)
480		return NULL;
481	for (ciw_cnt = 0; ciw_cnt < MAX_CIWS; ciw_cnt++)
482		if (cdev->private->senseid.ciw[ciw_cnt].ct == ct)
483			return cdev->private->senseid.ciw + ciw_cnt;
484	return NULL;
485}
486
487/**
488 * ccw_device_get_path_mask() - get currently available paths
489 * @cdev: ccw device to be queried
490 * Returns:
491 *  %0 if no subchannel for the device is available,
492 *  else the mask of currently available paths for the ccw device's subchannel.
493 */
494__u8 ccw_device_get_path_mask(struct ccw_device *cdev)
495{
496	struct subchannel *sch;
497
498	if (!cdev->dev.parent)
499		return 0;
500
501	sch = to_subchannel(cdev->dev.parent);
502	return sch->lpm;
503}
504
505struct stlck_data {
506	struct completion done;
507	int rc;
508};
509
510void ccw_device_stlck_done(struct ccw_device *cdev, void *data, int rc)
511{
512	struct stlck_data *sdata = data;
513
514	sdata->rc = rc;
515	complete(&sdata->done);
516}
517
518/*
519 * Perform unconditional reserve + release.
520 */
521int ccw_device_stlck(struct ccw_device *cdev)
522{
523	struct subchannel *sch = to_subchannel(cdev->dev.parent);
524	struct stlck_data data;
525	u8 *buffer;
526	int rc;
527
528	/* Check if steal lock operation is valid for this device. */
529	if (cdev->drv) {
530		if (!cdev->private->options.force)
531			return -EINVAL;
532	}
533	buffer = kzalloc(64, GFP_DMA | GFP_KERNEL);
534	if (!buffer)
535		return -ENOMEM;
536	init_completion(&data.done);
537	data.rc = -EIO;
538	spin_lock_irq(sch->lock);
539	rc = cio_enable_subchannel(sch, (u32) (addr_t) sch);
540	if (rc)
541		goto out_unlock;
542	/* Perform operation. */
543	cdev->private->state = DEV_STATE_STEAL_LOCK,
544	ccw_device_stlck_start(cdev, &data, &buffer[0], &buffer[32]);
545	spin_unlock_irq(sch->lock);
546	/* Wait for operation to finish. */
547	if (wait_for_completion_interruptible(&data.done)) {
548		/* Got a signal. */
549		spin_lock_irq(sch->lock);
550		ccw_request_cancel(cdev);
551		spin_unlock_irq(sch->lock);
552		wait_for_completion(&data.done);
553	}
554	rc = data.rc;
555	/* Check results. */
556	spin_lock_irq(sch->lock);
557	cio_disable_subchannel(sch);
558	cdev->private->state = DEV_STATE_BOXED;
559out_unlock:
560	spin_unlock_irq(sch->lock);
561	kfree(buffer);
562
563	return rc;
564}
565
566/**
567 * chp_get_chp_desc - return newly allocated channel-path descriptor
568 * @cdev: device to obtain the descriptor for
569 * @chp_idx: index of the channel path
570 *
571 * On success return a newly allocated copy of the channel-path description
572 * data associated with the given channel path. Return %NULL on error.
573 */
574struct channel_path_desc *ccw_device_get_chp_desc(struct ccw_device *cdev,
575						  int chp_idx)
576{
577	struct subchannel *sch;
578	struct chp_id chpid;
579
580	sch = to_subchannel(cdev->dev.parent);
581	chp_id_init(&chpid);
582	chpid.id = sch->schib.pmcw.chpid[chp_idx];
583	return chp_get_chp_desc(chpid);
584}
585
586/**
587 * ccw_device_get_id - obtain a ccw device id
588 * @cdev: device to obtain the id for
589 * @dev_id: where to fill in the values
590 */
591void ccw_device_get_id(struct ccw_device *cdev, struct ccw_dev_id *dev_id)
592{
593	*dev_id = cdev->private->dev_id;
594}
595EXPORT_SYMBOL(ccw_device_get_id);
596
597/**
598 * ccw_device_tm_start_key - perform start function
599 * @cdev: ccw device on which to perform the start function
600 * @tcw: transport-command word to be started
601 * @intparm: user defined parameter to be passed to the interrupt handler
602 * @lpm: mask of paths to use
603 * @key: storage key to use for storage access
604 *
605 * Start the tcw on the given ccw device. Return zero on success, non-zero
606 * otherwise.
607 */
608int ccw_device_tm_start_key(struct ccw_device *cdev, struct tcw *tcw,
609			    unsigned long intparm, u8 lpm, u8 key)
610{
611	struct subchannel *sch;
612	int rc;
613
614	sch = to_subchannel(cdev->dev.parent);
615	if (!sch->schib.pmcw.ena)
616		return -EINVAL;
617	if (cdev->private->state == DEV_STATE_VERIFY) {
618		/* Remember to fake irb when finished. */
619		if (!cdev->private->flags.fake_irb) {
620			cdev->private->flags.fake_irb = FAKE_TM_IRB;
621			cdev->private->intparm = intparm;
622			return 0;
623		} else
624			/* There's already a fake I/O around. */
625			return -EBUSY;
626	}
627	if (cdev->private->state != DEV_STATE_ONLINE)
628		return -EIO;
629	/* Adjust requested path mask to exclude unusable paths. */
630	if (lpm) {
631		lpm &= sch->lpm;
632		if (lpm == 0)
633			return -EACCES;
634	}
635	rc = cio_tm_start_key(sch, tcw, lpm, key);
636	if (rc == 0)
637		cdev->private->intparm = intparm;
638	return rc;
639}
640EXPORT_SYMBOL(ccw_device_tm_start_key);
641
642/**
643 * ccw_device_tm_start_timeout_key - perform start function
644 * @cdev: ccw device on which to perform the start function
645 * @tcw: transport-command word to be started
646 * @intparm: user defined parameter to be passed to the interrupt handler
647 * @lpm: mask of paths to use
648 * @key: storage key to use for storage access
649 * @expires: time span in jiffies after which to abort request
650 *
651 * Start the tcw on the given ccw device. Return zero on success, non-zero
652 * otherwise.
653 */
654int ccw_device_tm_start_timeout_key(struct ccw_device *cdev, struct tcw *tcw,
655				    unsigned long intparm, u8 lpm, u8 key,
656				    int expires)
657{
658	int ret;
659
660	ccw_device_set_timeout(cdev, expires);
661	ret = ccw_device_tm_start_key(cdev, tcw, intparm, lpm, key);
662	if (ret != 0)
663		ccw_device_set_timeout(cdev, 0);
664	return ret;
665}
666EXPORT_SYMBOL(ccw_device_tm_start_timeout_key);
667
668/**
669 * ccw_device_tm_start - perform start function
670 * @cdev: ccw device on which to perform the start function
671 * @tcw: transport-command word to be started
672 * @intparm: user defined parameter to be passed to the interrupt handler
673 * @lpm: mask of paths to use
674 *
675 * Start the tcw on the given ccw device. Return zero on success, non-zero
676 * otherwise.
677 */
678int ccw_device_tm_start(struct ccw_device *cdev, struct tcw *tcw,
679			unsigned long intparm, u8 lpm)
680{
681	return ccw_device_tm_start_key(cdev, tcw, intparm, lpm,
682				       PAGE_DEFAULT_KEY);
683}
684EXPORT_SYMBOL(ccw_device_tm_start);
685
686/**
687 * ccw_device_tm_start_timeout - perform start function
688 * @cdev: ccw device on which to perform the start function
689 * @tcw: transport-command word to be started
690 * @intparm: user defined parameter to be passed to the interrupt handler
691 * @lpm: mask of paths to use
692 * @expires: time span in jiffies after which to abort request
693 *
694 * Start the tcw on the given ccw device. Return zero on success, non-zero
695 * otherwise.
696 */
697int ccw_device_tm_start_timeout(struct ccw_device *cdev, struct tcw *tcw,
698			       unsigned long intparm, u8 lpm, int expires)
699{
700	return ccw_device_tm_start_timeout_key(cdev, tcw, intparm, lpm,
701					       PAGE_DEFAULT_KEY, expires);
702}
703EXPORT_SYMBOL(ccw_device_tm_start_timeout);
704
705/**
706 * ccw_device_get_mdc - accumulate max data count
707 * @cdev: ccw device for which the max data count is accumulated
708 * @mask: mask of paths to use
709 *
710 * Return the number of 64K-bytes blocks all paths at least support
711 * for a transport command. Return values <= 0 indicate failures.
712 */
713int ccw_device_get_mdc(struct ccw_device *cdev, u8 mask)
714{
715	struct subchannel *sch = to_subchannel(cdev->dev.parent);
716	struct channel_path *chp;
717	struct chp_id chpid;
718	int mdc = 0, i;
719
720	/* Adjust requested path mask to excluded varied off paths. */
721	if (mask)
722		mask &= sch->lpm;
723	else
724		mask = sch->lpm;
725
726	chp_id_init(&chpid);
727	for (i = 0; i < 8; i++) {
728		if (!(mask & (0x80 >> i)))
729			continue;
730		chpid.id = sch->schib.pmcw.chpid[i];
731		chp = chpid_to_chp(chpid);
732		if (!chp)
733			continue;
734
735		mutex_lock(&chp->lock);
736		if (!chp->desc_fmt1.f) {
737			mutex_unlock(&chp->lock);
738			return 0;
739		}
740		if (!chp->desc_fmt1.r)
741			mdc = 1;
742		mdc = mdc ? min_t(int, mdc, chp->desc_fmt1.mdc) :
743			    chp->desc_fmt1.mdc;
744		mutex_unlock(&chp->lock);
745	}
746
747	return mdc;
748}
749EXPORT_SYMBOL(ccw_device_get_mdc);
750
751/**
752 * ccw_device_tm_intrg - perform interrogate function
753 * @cdev: ccw device on which to perform the interrogate function
754 *
755 * Perform an interrogate function on the given ccw device. Return zero on
756 * success, non-zero otherwise.
757 */
758int ccw_device_tm_intrg(struct ccw_device *cdev)
759{
760	struct subchannel *sch = to_subchannel(cdev->dev.parent);
761
762	if (!sch->schib.pmcw.ena)
763		return -EINVAL;
764	if (cdev->private->state != DEV_STATE_ONLINE)
765		return -EIO;
766	if (!scsw_is_tm(&sch->schib.scsw) ||
767	    !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_START_PEND))
768		return -EINVAL;
769	return cio_tm_intrg(sch);
770}
771EXPORT_SYMBOL(ccw_device_tm_intrg);
772
773/**
774 * ccw_device_get_schid - obtain a subchannel id
775 * @cdev: device to obtain the id for
776 * @schid: where to fill in the values
777 */
778void ccw_device_get_schid(struct ccw_device *cdev, struct subchannel_id *schid)
779{
780	struct subchannel *sch = to_subchannel(cdev->dev.parent);
781
782	*schid = sch->schid;
783}
784EXPORT_SYMBOL_GPL(ccw_device_get_schid);
785
786MODULE_LICENSE("GPL");
787EXPORT_SYMBOL(ccw_device_set_options_mask);
788EXPORT_SYMBOL(ccw_device_set_options);
789EXPORT_SYMBOL(ccw_device_clear_options);
790EXPORT_SYMBOL(ccw_device_clear);
791EXPORT_SYMBOL(ccw_device_halt);
792EXPORT_SYMBOL(ccw_device_resume);
793EXPORT_SYMBOL(ccw_device_start_timeout);
794EXPORT_SYMBOL(ccw_device_start);
795EXPORT_SYMBOL(ccw_device_start_timeout_key);
796EXPORT_SYMBOL(ccw_device_start_key);
797EXPORT_SYMBOL(ccw_device_get_ciw);
798EXPORT_SYMBOL(ccw_device_get_path_mask);
799EXPORT_SYMBOL_GPL(ccw_device_get_chp_desc);
800