1// SPDX-License-Identifier: GPL-2.0
2/*
3 *  CCW device PGID and path verification I/O handling.
4 *
5 *    Copyright IBM Corp. 2002, 2009
6 *    Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
7 *		 Martin Schwidefsky <schwidefsky@de.ibm.com>
8 *		 Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
9 */
10
11#include <linux/kernel.h>
12#include <linux/string.h>
13#include <linux/bitops.h>
14#include <linux/types.h>
15#include <linux/errno.h>
16#include <linux/slab.h>
17#include <linux/io.h>
18#include <asm/ccwdev.h>
19#include <asm/cio.h>
20
21#include "cio.h"
22#include "cio_debug.h"
23#include "device.h"
24#include "io_sch.h"
25
26#define PGID_RETRIES	256
27#define PGID_TIMEOUT	(10 * HZ)
28
29static void verify_start(struct ccw_device *cdev);
30
31/*
32 * Process path verification data and report result.
33 */
34static void verify_done(struct ccw_device *cdev, int rc)
35{
36	struct subchannel *sch = to_subchannel(cdev->dev.parent);
37	struct ccw_dev_id *id = &cdev->private->dev_id;
38	int mpath = cdev->private->flags.mpath;
39	int pgroup = cdev->private->flags.pgroup;
40
41	if (rc)
42		goto out;
43	/* Ensure consistent multipathing state at device and channel. */
44	if (sch->config.mp != mpath) {
45		sch->config.mp = mpath;
46		rc = cio_commit_config(sch);
47	}
48out:
49	CIO_MSG_EVENT(2, "vrfy: device 0.%x.%04x: rc=%d pgroup=%d mpath=%d "
50			 "vpm=%02x\n", id->ssid, id->devno, rc, pgroup, mpath,
51			 sch->vpm);
52	ccw_device_verify_done(cdev, rc);
53}
54
55/*
56 * Create channel program to perform a NOOP.
57 */
58static void nop_build_cp(struct ccw_device *cdev)
59{
60	struct ccw_request *req = &cdev->private->req;
61	struct ccw1 *cp = cdev->private->dma_area->iccws;
62
63	cp->cmd_code	= CCW_CMD_NOOP;
64	cp->cda		= 0;
65	cp->count	= 0;
66	cp->flags	= CCW_FLAG_SLI;
67	req->cp		= cp;
68}
69
70/*
71 * Perform NOOP on a single path.
72 */
73static void nop_do(struct ccw_device *cdev)
74{
75	struct subchannel *sch = to_subchannel(cdev->dev.parent);
76	struct ccw_request *req = &cdev->private->req;
77
78	req->lpm = lpm_adjust(req->lpm, sch->schib.pmcw.pam & sch->opm &
79			      ~cdev->private->path_noirq_mask);
80	if (!req->lpm)
81		goto out_nopath;
82	nop_build_cp(cdev);
83	ccw_request_start(cdev);
84	return;
85
86out_nopath:
87	verify_done(cdev, sch->vpm ? 0 : -EACCES);
88}
89
90/*
91 * Adjust NOOP I/O status.
92 */
93static enum io_status nop_filter(struct ccw_device *cdev, void *data,
94				 struct irb *irb, enum io_status status)
95{
96	/* Only subchannel status might indicate a path error. */
97	if (status == IO_STATUS_ERROR && irb->scsw.cmd.cstat == 0)
98		return IO_DONE;
99	return status;
100}
101
102/*
103 * Process NOOP request result for a single path.
104 */
105static void nop_callback(struct ccw_device *cdev, void *data, int rc)
106{
107	struct subchannel *sch = to_subchannel(cdev->dev.parent);
108	struct ccw_request *req = &cdev->private->req;
109
110	switch (rc) {
111	case 0:
112		sch->vpm |= req->lpm;
113		break;
114	case -ETIME:
115		cdev->private->path_noirq_mask |= req->lpm;
116		break;
117	case -EACCES:
118		cdev->private->path_notoper_mask |= req->lpm;
119		break;
120	default:
121		goto err;
122	}
123	/* Continue on the next path. */
124	req->lpm >>= 1;
125	nop_do(cdev);
126	return;
127
128err:
129	verify_done(cdev, rc);
130}
131
132/*
133 * Create channel program to perform SET PGID on a single path.
134 */
135static void spid_build_cp(struct ccw_device *cdev, u8 fn)
136{
137	struct ccw_request *req = &cdev->private->req;
138	struct ccw1 *cp = cdev->private->dma_area->iccws;
139	int i = pathmask_to_pos(req->lpm);
140	struct pgid *pgid = &cdev->private->dma_area->pgid[i];
141
142	pgid->inf.fc	= fn;
143	cp->cmd_code	= CCW_CMD_SET_PGID;
144	cp->cda		= (u32)virt_to_phys(pgid);
145	cp->count	= sizeof(*pgid);
146	cp->flags	= CCW_FLAG_SLI;
147	req->cp		= cp;
148}
149
150static void pgid_wipeout_callback(struct ccw_device *cdev, void *data, int rc)
151{
152	if (rc) {
153		/* We don't know the path groups' state. Abort. */
154		verify_done(cdev, rc);
155		return;
156	}
157	/*
158	 * Path groups have been reset. Restart path verification but
159	 * leave paths in path_noirq_mask out.
160	 */
161	cdev->private->flags.pgid_unknown = 0;
162	verify_start(cdev);
163}
164
165/*
166 * Reset pathgroups and restart path verification, leave unusable paths out.
167 */
168static void pgid_wipeout_start(struct ccw_device *cdev)
169{
170	struct subchannel *sch = to_subchannel(cdev->dev.parent);
171	struct ccw_dev_id *id = &cdev->private->dev_id;
172	struct ccw_request *req = &cdev->private->req;
173	u8 fn;
174
175	CIO_MSG_EVENT(2, "wipe: device 0.%x.%04x: pvm=%02x nim=%02x\n",
176		      id->ssid, id->devno, cdev->private->pgid_valid_mask,
177		      cdev->private->path_noirq_mask);
178
179	/* Initialize request data. */
180	memset(req, 0, sizeof(*req));
181	req->timeout	= PGID_TIMEOUT;
182	req->maxretries	= PGID_RETRIES;
183	req->lpm	= sch->schib.pmcw.pam;
184	req->callback	= pgid_wipeout_callback;
185	fn = SPID_FUNC_DISBAND;
186	if (cdev->private->flags.mpath)
187		fn |= SPID_FUNC_MULTI_PATH;
188	spid_build_cp(cdev, fn);
189	ccw_request_start(cdev);
190}
191
192/*
193 * Perform establish/resign SET PGID on a single path.
194 */
195static void spid_do(struct ccw_device *cdev)
196{
197	struct subchannel *sch = to_subchannel(cdev->dev.parent);
198	struct ccw_request *req = &cdev->private->req;
199	u8 fn;
200
201	/* Use next available path that is not already in correct state. */
202	req->lpm = lpm_adjust(req->lpm, cdev->private->pgid_todo_mask);
203	if (!req->lpm)
204		goto out_nopath;
205	/* Channel program setup. */
206	if (req->lpm & sch->opm)
207		fn = SPID_FUNC_ESTABLISH;
208	else
209		fn = SPID_FUNC_RESIGN;
210	if (cdev->private->flags.mpath)
211		fn |= SPID_FUNC_MULTI_PATH;
212	spid_build_cp(cdev, fn);
213	ccw_request_start(cdev);
214	return;
215
216out_nopath:
217	if (cdev->private->flags.pgid_unknown) {
218		/* At least one SPID could be partially done. */
219		pgid_wipeout_start(cdev);
220		return;
221	}
222	verify_done(cdev, sch->vpm ? 0 : -EACCES);
223}
224
225/*
226 * Process SET PGID request result for a single path.
227 */
228static void spid_callback(struct ccw_device *cdev, void *data, int rc)
229{
230	struct subchannel *sch = to_subchannel(cdev->dev.parent);
231	struct ccw_request *req = &cdev->private->req;
232
233	switch (rc) {
234	case 0:
235		sch->vpm |= req->lpm & sch->opm;
236		break;
237	case -ETIME:
238		cdev->private->flags.pgid_unknown = 1;
239		cdev->private->path_noirq_mask |= req->lpm;
240		break;
241	case -EACCES:
242		cdev->private->path_notoper_mask |= req->lpm;
243		break;
244	case -EOPNOTSUPP:
245		if (cdev->private->flags.mpath) {
246			/* Try without multipathing. */
247			cdev->private->flags.mpath = 0;
248			goto out_restart;
249		}
250		/* Try without pathgrouping. */
251		cdev->private->flags.pgroup = 0;
252		goto out_restart;
253	default:
254		goto err;
255	}
256	req->lpm >>= 1;
257	spid_do(cdev);
258	return;
259
260out_restart:
261	verify_start(cdev);
262	return;
263err:
264	verify_done(cdev, rc);
265}
266
267static void spid_start(struct ccw_device *cdev)
268{
269	struct ccw_request *req = &cdev->private->req;
270
271	/* Initialize request data. */
272	memset(req, 0, sizeof(*req));
273	req->timeout	= PGID_TIMEOUT;
274	req->maxretries	= PGID_RETRIES;
275	req->lpm	= 0x80;
276	req->singlepath	= 1;
277	req->callback	= spid_callback;
278	spid_do(cdev);
279}
280
281static int pgid_is_reset(struct pgid *p)
282{
283	char *c;
284
285	for (c = (char *)p + 1; c < (char *)(p + 1); c++) {
286		if (*c != 0)
287			return 0;
288	}
289	return 1;
290}
291
292static int pgid_cmp(struct pgid *p1, struct pgid *p2)
293{
294	return memcmp((char *) p1 + 1, (char *) p2 + 1,
295		      sizeof(struct pgid) - 1);
296}
297
298/*
299 * Determine pathgroup state from PGID data.
300 */
301static void pgid_analyze(struct ccw_device *cdev, struct pgid **p,
302			 int *mismatch, u8 *reserved, u8 *reset)
303{
304	struct pgid *pgid = &cdev->private->dma_area->pgid[0];
305	struct pgid *first = NULL;
306	int lpm;
307	int i;
308
309	*mismatch = 0;
310	*reserved = 0;
311	*reset = 0;
312	for (i = 0, lpm = 0x80; i < 8; i++, pgid++, lpm >>= 1) {
313		if ((cdev->private->pgid_valid_mask & lpm) == 0)
314			continue;
315		if (pgid->inf.ps.state2 == SNID_STATE2_RESVD_ELSE)
316			*reserved |= lpm;
317		if (pgid_is_reset(pgid)) {
318			*reset |= lpm;
319			continue;
320		}
321		if (!first) {
322			first = pgid;
323			continue;
324		}
325		if (pgid_cmp(pgid, first) != 0)
326			*mismatch = 1;
327	}
328	if (!first)
329		first = &channel_subsystems[0]->global_pgid;
330	*p = first;
331}
332
333static u8 pgid_to_donepm(struct ccw_device *cdev)
334{
335	struct subchannel *sch = to_subchannel(cdev->dev.parent);
336	struct pgid *pgid;
337	int i;
338	int lpm;
339	u8 donepm = 0;
340
341	/* Set bits for paths which are already in the target state. */
342	for (i = 0; i < 8; i++) {
343		lpm = 0x80 >> i;
344		if ((cdev->private->pgid_valid_mask & lpm) == 0)
345			continue;
346		pgid = &cdev->private->dma_area->pgid[i];
347		if (sch->opm & lpm) {
348			if (pgid->inf.ps.state1 != SNID_STATE1_GROUPED)
349				continue;
350		} else {
351			if (pgid->inf.ps.state1 != SNID_STATE1_UNGROUPED)
352				continue;
353		}
354		if (cdev->private->flags.mpath) {
355			if (pgid->inf.ps.state3 != SNID_STATE3_MULTI_PATH)
356				continue;
357		} else {
358			if (pgid->inf.ps.state3 != SNID_STATE3_SINGLE_PATH)
359				continue;
360		}
361		donepm |= lpm;
362	}
363
364	return donepm;
365}
366
367static void pgid_fill(struct ccw_device *cdev, struct pgid *pgid)
368{
369	int i;
370
371	for (i = 0; i < 8; i++)
372		memcpy(&cdev->private->dma_area->pgid[i], pgid,
373		       sizeof(struct pgid));
374}
375
376/*
377 * Process SENSE PGID data and report result.
378 */
379static void snid_done(struct ccw_device *cdev, int rc)
380{
381	struct ccw_dev_id *id = &cdev->private->dev_id;
382	struct subchannel *sch = to_subchannel(cdev->dev.parent);
383	struct pgid *pgid;
384	int mismatch = 0;
385	u8 reserved = 0;
386	u8 reset = 0;
387	u8 donepm;
388
389	if (rc)
390		goto out;
391	pgid_analyze(cdev, &pgid, &mismatch, &reserved, &reset);
392	if (reserved == cdev->private->pgid_valid_mask)
393		rc = -EUSERS;
394	else if (mismatch)
395		rc = -EOPNOTSUPP;
396	else {
397		donepm = pgid_to_donepm(cdev);
398		sch->vpm = donepm & sch->opm;
399		cdev->private->pgid_reset_mask |= reset;
400		cdev->private->pgid_todo_mask &=
401			~(donepm | cdev->private->path_noirq_mask);
402		pgid_fill(cdev, pgid);
403	}
404out:
405	CIO_MSG_EVENT(2, "snid: device 0.%x.%04x: rc=%d pvm=%02x vpm=%02x "
406		      "todo=%02x mism=%d rsvd=%02x reset=%02x\n", id->ssid,
407		      id->devno, rc, cdev->private->pgid_valid_mask, sch->vpm,
408		      cdev->private->pgid_todo_mask, mismatch, reserved, reset);
409	switch (rc) {
410	case 0:
411		if (cdev->private->flags.pgid_unknown) {
412			pgid_wipeout_start(cdev);
413			return;
414		}
415		/* Anything left to do? */
416		if (cdev->private->pgid_todo_mask == 0) {
417			verify_done(cdev, sch->vpm == 0 ? -EACCES : 0);
418			return;
419		}
420		/* Perform path-grouping. */
421		spid_start(cdev);
422		break;
423	case -EOPNOTSUPP:
424		/* Path-grouping not supported. */
425		cdev->private->flags.pgroup = 0;
426		cdev->private->flags.mpath = 0;
427		verify_start(cdev);
428		break;
429	default:
430		verify_done(cdev, rc);
431	}
432}
433
434/*
435 * Create channel program to perform a SENSE PGID on a single path.
436 */
437static void snid_build_cp(struct ccw_device *cdev)
438{
439	struct ccw_request *req = &cdev->private->req;
440	struct ccw1 *cp = cdev->private->dma_area->iccws;
441	int i = pathmask_to_pos(req->lpm);
442
443	/* Channel program setup. */
444	cp->cmd_code	= CCW_CMD_SENSE_PGID;
445	cp->cda		= (u32)virt_to_phys(&cdev->private->dma_area->pgid[i]);
446	cp->count	= sizeof(struct pgid);
447	cp->flags	= CCW_FLAG_SLI;
448	req->cp		= cp;
449}
450
451/*
452 * Perform SENSE PGID on a single path.
453 */
454static void snid_do(struct ccw_device *cdev)
455{
456	struct subchannel *sch = to_subchannel(cdev->dev.parent);
457	struct ccw_request *req = &cdev->private->req;
458	int ret;
459
460	req->lpm = lpm_adjust(req->lpm, sch->schib.pmcw.pam &
461			      ~cdev->private->path_noirq_mask);
462	if (!req->lpm)
463		goto out_nopath;
464	snid_build_cp(cdev);
465	ccw_request_start(cdev);
466	return;
467
468out_nopath:
469	if (cdev->private->pgid_valid_mask)
470		ret = 0;
471	else if (cdev->private->path_noirq_mask)
472		ret = -ETIME;
473	else
474		ret = -EACCES;
475	snid_done(cdev, ret);
476}
477
478/*
479 * Process SENSE PGID request result for single path.
480 */
481static void snid_callback(struct ccw_device *cdev, void *data, int rc)
482{
483	struct ccw_request *req = &cdev->private->req;
484
485	switch (rc) {
486	case 0:
487		cdev->private->pgid_valid_mask |= req->lpm;
488		break;
489	case -ETIME:
490		cdev->private->flags.pgid_unknown = 1;
491		cdev->private->path_noirq_mask |= req->lpm;
492		break;
493	case -EACCES:
494		cdev->private->path_notoper_mask |= req->lpm;
495		break;
496	default:
497		goto err;
498	}
499	/* Continue on the next path. */
500	req->lpm >>= 1;
501	snid_do(cdev);
502	return;
503
504err:
505	snid_done(cdev, rc);
506}
507
508/*
509 * Perform path verification.
510 */
511static void verify_start(struct ccw_device *cdev)
512{
513	struct subchannel *sch = to_subchannel(cdev->dev.parent);
514	struct ccw_request *req = &cdev->private->req;
515	struct ccw_dev_id *devid = &cdev->private->dev_id;
516
517	sch->vpm = 0;
518	sch->lpm = sch->schib.pmcw.pam;
519
520	/* Initialize PGID data. */
521	memset(cdev->private->dma_area->pgid, 0,
522	       sizeof(cdev->private->dma_area->pgid));
523	cdev->private->pgid_valid_mask = 0;
524	cdev->private->pgid_todo_mask = sch->schib.pmcw.pam;
525	cdev->private->path_notoper_mask = 0;
526
527	/* Initialize request data. */
528	memset(req, 0, sizeof(*req));
529	req->timeout	= PGID_TIMEOUT;
530	req->maxretries	= PGID_RETRIES;
531	req->lpm	= 0x80;
532	req->singlepath	= 1;
533	if (cdev->private->flags.pgroup) {
534		CIO_TRACE_EVENT(4, "snid");
535		CIO_HEX_EVENT(4, devid, sizeof(*devid));
536		req->callback	= snid_callback;
537		snid_do(cdev);
538	} else {
539		CIO_TRACE_EVENT(4, "nop");
540		CIO_HEX_EVENT(4, devid, sizeof(*devid));
541		req->filter	= nop_filter;
542		req->callback	= nop_callback;
543		nop_do(cdev);
544	}
545}
546
547/**
548 * ccw_device_verify_start - perform path verification
549 * @cdev: ccw device
550 *
551 * Perform an I/O on each available channel path to @cdev to determine which
552 * paths are operational. The resulting path mask is stored in sch->vpm.
553 * If device options specify pathgrouping, establish a pathgroup for the
554 * operational paths. When finished, call ccw_device_verify_done with a
555 * return code specifying the result.
556 */
557void ccw_device_verify_start(struct ccw_device *cdev)
558{
559	CIO_TRACE_EVENT(4, "vrfy");
560	CIO_HEX_EVENT(4, &cdev->private->dev_id, sizeof(cdev->private->dev_id));
561	/*
562	 * Initialize pathgroup and multipath state with target values.
563	 * They may change in the course of path verification.
564	 */
565	cdev->private->flags.pgroup = cdev->private->options.pgroup;
566	cdev->private->flags.mpath = cdev->private->options.mpath;
567	cdev->private->flags.doverify = 0;
568	cdev->private->path_noirq_mask = 0;
569	verify_start(cdev);
570}
571
572/*
573 * Process disband SET PGID request result.
574 */
575static void disband_callback(struct ccw_device *cdev, void *data, int rc)
576{
577	struct subchannel *sch = to_subchannel(cdev->dev.parent);
578	struct ccw_dev_id *id = &cdev->private->dev_id;
579
580	if (rc)
581		goto out;
582	/* Ensure consistent multipathing state at device and channel. */
583	cdev->private->flags.mpath = 0;
584	if (sch->config.mp) {
585		sch->config.mp = 0;
586		rc = cio_commit_config(sch);
587	}
588out:
589	CIO_MSG_EVENT(0, "disb: device 0.%x.%04x: rc=%d\n", id->ssid, id->devno,
590		      rc);
591	ccw_device_disband_done(cdev, rc);
592}
593
594/**
595 * ccw_device_disband_start - disband pathgroup
596 * @cdev: ccw device
597 *
598 * Execute a SET PGID channel program on @cdev to disband a previously
599 * established pathgroup. When finished, call ccw_device_disband_done with
600 * a return code specifying the result.
601 */
602void ccw_device_disband_start(struct ccw_device *cdev)
603{
604	struct subchannel *sch = to_subchannel(cdev->dev.parent);
605	struct ccw_request *req = &cdev->private->req;
606	u8 fn;
607
608	CIO_TRACE_EVENT(4, "disb");
609	CIO_HEX_EVENT(4, &cdev->private->dev_id, sizeof(cdev->private->dev_id));
610	/* Request setup. */
611	memset(req, 0, sizeof(*req));
612	req->timeout	= PGID_TIMEOUT;
613	req->maxretries	= PGID_RETRIES;
614	req->lpm	= sch->schib.pmcw.pam & sch->opm;
615	req->singlepath	= 1;
616	req->callback	= disband_callback;
617	fn = SPID_FUNC_DISBAND;
618	if (cdev->private->flags.mpath)
619		fn |= SPID_FUNC_MULTI_PATH;
620	spid_build_cp(cdev, fn);
621	ccw_request_start(cdev);
622}
623
624struct stlck_data {
625	struct completion done;
626	int rc;
627};
628
629static void stlck_build_cp(struct ccw_device *cdev, void *buf1, void *buf2)
630{
631	struct ccw_request *req = &cdev->private->req;
632	struct ccw1 *cp = cdev->private->dma_area->iccws;
633
634	cp[0].cmd_code = CCW_CMD_STLCK;
635	cp[0].cda = (u32)virt_to_phys(buf1);
636	cp[0].count = 32;
637	cp[0].flags = CCW_FLAG_CC;
638	cp[1].cmd_code = CCW_CMD_RELEASE;
639	cp[1].cda = (u32)virt_to_phys(buf2);
640	cp[1].count = 32;
641	cp[1].flags = 0;
642	req->cp = cp;
643}
644
645static void stlck_callback(struct ccw_device *cdev, void *data, int rc)
646{
647	struct stlck_data *sdata = data;
648
649	sdata->rc = rc;
650	complete(&sdata->done);
651}
652
653/**
654 * ccw_device_stlck_start - perform unconditional release
655 * @cdev: ccw device
656 * @data: data pointer to be passed to ccw_device_stlck_done
657 * @buf1: data pointer used in channel program
658 * @buf2: data pointer used in channel program
659 *
660 * Execute a channel program on @cdev to release an existing PGID reservation.
661 */
662static void ccw_device_stlck_start(struct ccw_device *cdev, void *data,
663				   void *buf1, void *buf2)
664{
665	struct subchannel *sch = to_subchannel(cdev->dev.parent);
666	struct ccw_request *req = &cdev->private->req;
667
668	CIO_TRACE_EVENT(4, "stlck");
669	CIO_HEX_EVENT(4, &cdev->private->dev_id, sizeof(cdev->private->dev_id));
670	/* Request setup. */
671	memset(req, 0, sizeof(*req));
672	req->timeout	= PGID_TIMEOUT;
673	req->maxretries	= PGID_RETRIES;
674	req->lpm	= sch->schib.pmcw.pam & sch->opm;
675	req->data	= data;
676	req->callback	= stlck_callback;
677	stlck_build_cp(cdev, buf1, buf2);
678	ccw_request_start(cdev);
679}
680
681/*
682 * Perform unconditional reserve + release.
683 */
684int ccw_device_stlck(struct ccw_device *cdev)
685{
686	struct subchannel *sch = to_subchannel(cdev->dev.parent);
687	struct stlck_data data;
688	u8 *buffer;
689	int rc;
690
691	/* Check if steal lock operation is valid for this device. */
692	if (cdev->drv) {
693		if (!cdev->private->options.force)
694			return -EINVAL;
695	}
696	buffer = kzalloc(64, GFP_DMA | GFP_KERNEL);
697	if (!buffer)
698		return -ENOMEM;
699	init_completion(&data.done);
700	data.rc = -EIO;
701	spin_lock_irq(sch->lock);
702	rc = cio_enable_subchannel(sch, (u32)virt_to_phys(sch));
703	if (rc)
704		goto out_unlock;
705	/* Perform operation. */
706	cdev->private->state = DEV_STATE_STEAL_LOCK;
707	ccw_device_stlck_start(cdev, &data, &buffer[0], &buffer[32]);
708	spin_unlock_irq(sch->lock);
709	/* Wait for operation to finish. */
710	if (wait_for_completion_interruptible(&data.done)) {
711		/* Got a signal. */
712		spin_lock_irq(sch->lock);
713		ccw_request_cancel(cdev);
714		spin_unlock_irq(sch->lock);
715		wait_for_completion(&data.done);
716	}
717	rc = data.rc;
718	/* Check results. */
719	spin_lock_irq(sch->lock);
720	cio_disable_subchannel(sch);
721	cdev->private->state = DEV_STATE_BOXED;
722out_unlock:
723	spin_unlock_irq(sch->lock);
724	kfree(buffer);
725
726	return rc;
727}
728