Merge branch 'linux-next' of git://git.infradead.org/~dedekind/ubi-2.6
[linux-2.6] / drivers / s390 / cio / chsc.c
1 /*
2  *  drivers/s390/cio/chsc.c
3  *   S/390 common I/O routines -- channel subsystem call
4  *
5  *    Copyright IBM Corp. 1999,2008
6  *    Author(s): Ingo Adlung (adlung@de.ibm.com)
7  *               Cornelia Huck (cornelia.huck@de.ibm.com)
8  *               Arnd Bergmann (arndb@de.ibm.com)
9  */
10
11 #include <linux/module.h>
12 #include <linux/slab.h>
13 #include <linux/init.h>
14 #include <linux/device.h>
15
16 #include <asm/cio.h>
17 #include <asm/chpid.h>
18 #include <asm/chsc.h>
19
20 #include "../s390mach.h"
21 #include "css.h"
22 #include "cio.h"
23 #include "cio_debug.h"
24 #include "ioasm.h"
25 #include "chp.h"
26 #include "chsc.h"
27
28 static void *sei_page;
29
30 /**
31  * chsc_error_from_response() - convert a chsc response to an error
32  * @response: chsc response code
33  *
34  * Returns an appropriate Linux error code for @response.
35  */
36 int chsc_error_from_response(int response)
37 {
38         switch (response) {
39         case 0x0001:
40                 return 0;
41         case 0x0002:
42         case 0x0003:
43         case 0x0006:
44         case 0x0007:
45         case 0x0008:
46         case 0x000a:
47                 return -EINVAL;
48         case 0x0004:
49                 return -EOPNOTSUPP;
50         default:
51                 return -EIO;
52         }
53 }
54 EXPORT_SYMBOL_GPL(chsc_error_from_response);
55
56 struct chsc_ssd_area {
57         struct chsc_header request;
58         u16 :10;
59         u16 ssid:2;
60         u16 :4;
61         u16 f_sch;        /* first subchannel */
62         u16 :16;
63         u16 l_sch;        /* last subchannel */
64         u32 :32;
65         struct chsc_header response;
66         u32 :32;
67         u8 sch_valid : 1;
68         u8 dev_valid : 1;
69         u8 st        : 3; /* subchannel type */
70         u8 zeroes    : 3;
71         u8  unit_addr;    /* unit address */
72         u16 devno;        /* device number */
73         u8 path_mask;
74         u8 fla_valid_mask;
75         u16 sch;          /* subchannel */
76         u8 chpid[8];      /* chpids 0-7 */
77         u16 fla[8];       /* full link addresses 0-7 */
78 } __attribute__ ((packed));
79
80 int chsc_get_ssd_info(struct subchannel_id schid, struct chsc_ssd_info *ssd)
81 {
82         unsigned long page;
83         struct chsc_ssd_area *ssd_area;
84         int ccode;
85         int ret;
86         int i;
87         int mask;
88
89         page = get_zeroed_page(GFP_KERNEL | GFP_DMA);
90         if (!page)
91                 return -ENOMEM;
92         ssd_area = (struct chsc_ssd_area *) page;
93         ssd_area->request.length = 0x0010;
94         ssd_area->request.code = 0x0004;
95         ssd_area->ssid = schid.ssid;
96         ssd_area->f_sch = schid.sch_no;
97         ssd_area->l_sch = schid.sch_no;
98
99         ccode = chsc(ssd_area);
100         /* Check response. */
101         if (ccode > 0) {
102                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
103                 goto out_free;
104         }
105         ret = chsc_error_from_response(ssd_area->response.code);
106         if (ret != 0) {
107                 CIO_MSG_EVENT(2, "chsc: ssd failed for 0.%x.%04x (rc=%04x)\n",
108                               schid.ssid, schid.sch_no,
109                               ssd_area->response.code);
110                 goto out_free;
111         }
112         if (!ssd_area->sch_valid) {
113                 ret = -ENODEV;
114                 goto out_free;
115         }
116         /* Copy data */
117         ret = 0;
118         memset(ssd, 0, sizeof(struct chsc_ssd_info));
119         if ((ssd_area->st != SUBCHANNEL_TYPE_IO) &&
120             (ssd_area->st != SUBCHANNEL_TYPE_MSG))
121                 goto out_free;
122         ssd->path_mask = ssd_area->path_mask;
123         ssd->fla_valid_mask = ssd_area->fla_valid_mask;
124         for (i = 0; i < 8; i++) {
125                 mask = 0x80 >> i;
126                 if (ssd_area->path_mask & mask) {
127                         chp_id_init(&ssd->chpid[i]);
128                         ssd->chpid[i].id = ssd_area->chpid[i];
129                 }
130                 if (ssd_area->fla_valid_mask & mask)
131                         ssd->fla[i] = ssd_area->fla[i];
132         }
133 out_free:
134         free_page(page);
135         return ret;
136 }
137
138 static int s390_subchannel_remove_chpid(struct subchannel *sch, void *data)
139 {
140         spin_lock_irq(sch->lock);
141         if (sch->driver && sch->driver->chp_event)
142                 if (sch->driver->chp_event(sch, data, CHP_OFFLINE) != 0)
143                         goto out_unreg;
144         spin_unlock_irq(sch->lock);
145         return 0;
146
147 out_unreg:
148         sch->lpm = 0;
149         spin_unlock_irq(sch->lock);
150         css_schedule_eval(sch->schid);
151         return 0;
152 }
153
154 void chsc_chp_offline(struct chp_id chpid)
155 {
156         char dbf_txt[15];
157         struct chp_link link;
158
159         sprintf(dbf_txt, "chpr%x.%02x", chpid.cssid, chpid.id);
160         CIO_TRACE_EVENT(2, dbf_txt);
161
162         if (chp_get_status(chpid) <= 0)
163                 return;
164         memset(&link, 0, sizeof(struct chp_link));
165         link.chpid = chpid;
166         /* Wait until previous actions have settled. */
167         css_wait_for_slow_path();
168         for_each_subchannel_staged(s390_subchannel_remove_chpid, NULL, &link);
169 }
170
171 static int s390_process_res_acc_new_sch(struct subchannel_id schid, void *data)
172 {
173         struct schib schib;
174         /*
175          * We don't know the device yet, but since a path
176          * may be available now to the device we'll have
177          * to do recognition again.
178          * Since we don't have any idea about which chpid
179          * that beast may be on we'll have to do a stsch
180          * on all devices, grr...
181          */
182         if (stsch_err(schid, &schib))
183                 /* We're through */
184                 return -ENXIO;
185
186         /* Put it on the slow path. */
187         css_schedule_eval(schid);
188         return 0;
189 }
190
191 static int __s390_process_res_acc(struct subchannel *sch, void *data)
192 {
193         spin_lock_irq(sch->lock);
194         if (sch->driver && sch->driver->chp_event)
195                 sch->driver->chp_event(sch, data, CHP_ONLINE);
196         spin_unlock_irq(sch->lock);
197
198         return 0;
199 }
200
201 static void s390_process_res_acc(struct chp_link *link)
202 {
203         char dbf_txt[15];
204
205         sprintf(dbf_txt, "accpr%x.%02x", link->chpid.cssid,
206                 link->chpid.id);
207         CIO_TRACE_EVENT( 2, dbf_txt);
208         if (link->fla != 0) {
209                 sprintf(dbf_txt, "fla%x", link->fla);
210                 CIO_TRACE_EVENT( 2, dbf_txt);
211         }
212         /* Wait until previous actions have settled. */
213         css_wait_for_slow_path();
214         /*
215          * I/O resources may have become accessible.
216          * Scan through all subchannels that may be concerned and
217          * do a validation on those.
218          * The more information we have (info), the less scanning
219          * will we have to do.
220          */
221         for_each_subchannel_staged(__s390_process_res_acc,
222                                    s390_process_res_acc_new_sch, link);
223 }
224
225 static int
226 __get_chpid_from_lir(void *data)
227 {
228         struct lir {
229                 u8  iq;
230                 u8  ic;
231                 u16 sci;
232                 /* incident-node descriptor */
233                 u32 indesc[28];
234                 /* attached-node descriptor */
235                 u32 andesc[28];
236                 /* incident-specific information */
237                 u32 isinfo[28];
238         } __attribute__ ((packed)) *lir;
239
240         lir = data;
241         if (!(lir->iq&0x80))
242                 /* NULL link incident record */
243                 return -EINVAL;
244         if (!(lir->indesc[0]&0xc0000000))
245                 /* node descriptor not valid */
246                 return -EINVAL;
247         if (!(lir->indesc[0]&0x10000000))
248                 /* don't handle device-type nodes - FIXME */
249                 return -EINVAL;
250         /* Byte 3 contains the chpid. Could also be CTCA, but we don't care */
251
252         return (u16) (lir->indesc[0]&0x000000ff);
253 }
254
255 struct chsc_sei_area {
256         struct chsc_header request;
257         u32 reserved1;
258         u32 reserved2;
259         u32 reserved3;
260         struct chsc_header response;
261         u32 reserved4;
262         u8  flags;
263         u8  vf;         /* validity flags */
264         u8  rs;         /* reporting source */
265         u8  cc;         /* content code */
266         u16 fla;        /* full link address */
267         u16 rsid;       /* reporting source id */
268         u32 reserved5;
269         u32 reserved6;
270         u8 ccdf[4096 - 16 - 24];        /* content-code dependent field */
271         /* ccdf has to be big enough for a link-incident record */
272 } __attribute__ ((packed));
273
274 static void chsc_process_sei_link_incident(struct chsc_sei_area *sei_area)
275 {
276         struct chp_id chpid;
277         int id;
278
279         CIO_CRW_EVENT(4, "chsc: link incident (rs=%02x, rs_id=%04x)\n",
280                       sei_area->rs, sei_area->rsid);
281         if (sei_area->rs != 4)
282                 return;
283         id = __get_chpid_from_lir(sei_area->ccdf);
284         if (id < 0)
285                 CIO_CRW_EVENT(4, "chsc: link incident - invalid LIR\n");
286         else {
287                 chp_id_init(&chpid);
288                 chpid.id = id;
289                 chsc_chp_offline(chpid);
290         }
291 }
292
293 static void chsc_process_sei_res_acc(struct chsc_sei_area *sei_area)
294 {
295         struct chp_link link;
296         struct chp_id chpid;
297         int status;
298
299         CIO_CRW_EVENT(4, "chsc: resource accessibility event (rs=%02x, "
300                       "rs_id=%04x)\n", sei_area->rs, sei_area->rsid);
301         if (sei_area->rs != 4)
302                 return;
303         chp_id_init(&chpid);
304         chpid.id = sei_area->rsid;
305         /* allocate a new channel path structure, if needed */
306         status = chp_get_status(chpid);
307         if (status < 0)
308                 chp_new(chpid);
309         else if (!status)
310                 return;
311         memset(&link, 0, sizeof(struct chp_link));
312         link.chpid = chpid;
313         if ((sei_area->vf & 0xc0) != 0) {
314                 link.fla = sei_area->fla;
315                 if ((sei_area->vf & 0xc0) == 0xc0)
316                         /* full link address */
317                         link.fla_mask = 0xffff;
318                 else
319                         /* link address */
320                         link.fla_mask = 0xff00;
321         }
322         s390_process_res_acc(&link);
323 }
324
325 struct chp_config_data {
326         u8 map[32];
327         u8 op;
328         u8 pc;
329 };
330
331 static void chsc_process_sei_chp_config(struct chsc_sei_area *sei_area)
332 {
333         struct chp_config_data *data;
334         struct chp_id chpid;
335         int num;
336
337         CIO_CRW_EVENT(4, "chsc: channel-path-configuration notification\n");
338         if (sei_area->rs != 0)
339                 return;
340         data = (struct chp_config_data *) &(sei_area->ccdf);
341         chp_id_init(&chpid);
342         for (num = 0; num <= __MAX_CHPID; num++) {
343                 if (!chp_test_bit(data->map, num))
344                         continue;
345                 chpid.id = num;
346                 printk(KERN_WARNING "cio: processing configure event %d for "
347                        "chpid %x.%02x\n", data->op, chpid.cssid, chpid.id);
348                 switch (data->op) {
349                 case 0:
350                         chp_cfg_schedule(chpid, 1);
351                         break;
352                 case 1:
353                         chp_cfg_schedule(chpid, 0);
354                         break;
355                 case 2:
356                         chp_cfg_cancel_deconfigure(chpid);
357                         break;
358                 }
359         }
360 }
361
362 static void chsc_process_sei(struct chsc_sei_area *sei_area)
363 {
364         /* Check if we might have lost some information. */
365         if (sei_area->flags & 0x40) {
366                 CIO_CRW_EVENT(2, "chsc: event overflow\n");
367                 css_schedule_eval_all();
368         }
369         /* which kind of information was stored? */
370         switch (sei_area->cc) {
371         case 1: /* link incident*/
372                 chsc_process_sei_link_incident(sei_area);
373                 break;
374         case 2: /* i/o resource accessibiliy */
375                 chsc_process_sei_res_acc(sei_area);
376                 break;
377         case 8: /* channel-path-configuration notification */
378                 chsc_process_sei_chp_config(sei_area);
379                 break;
380         default: /* other stuff */
381                 CIO_CRW_EVENT(4, "chsc: unhandled sei content code %d\n",
382                               sei_area->cc);
383                 break;
384         }
385 }
386
387 static void chsc_process_crw(struct crw *crw0, struct crw *crw1, int overflow)
388 {
389         struct chsc_sei_area *sei_area;
390
391         if (overflow) {
392                 css_schedule_eval_all();
393                 return;
394         }
395         CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
396                       "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
397                       crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
398                       crw0->erc, crw0->rsid);
399         if (!sei_page)
400                 return;
401         /* Access to sei_page is serialized through machine check handler
402          * thread, so no need for locking. */
403         sei_area = sei_page;
404
405         CIO_TRACE_EVENT(2, "prcss");
406         do {
407                 memset(sei_area, 0, sizeof(*sei_area));
408                 sei_area->request.length = 0x0010;
409                 sei_area->request.code = 0x000e;
410                 if (chsc(sei_area))
411                         break;
412
413                 if (sei_area->response.code == 0x0001) {
414                         CIO_CRW_EVENT(4, "chsc: sei successful\n");
415                         chsc_process_sei(sei_area);
416                 } else {
417                         CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x)\n",
418                                       sei_area->response.code);
419                         break;
420                 }
421         } while (sei_area->flags & 0x80);
422 }
423
424 void chsc_chp_online(struct chp_id chpid)
425 {
426         char dbf_txt[15];
427         struct chp_link link;
428
429         sprintf(dbf_txt, "cadd%x.%02x", chpid.cssid, chpid.id);
430         CIO_TRACE_EVENT(2, dbf_txt);
431
432         if (chp_get_status(chpid) != 0) {
433                 memset(&link, 0, sizeof(struct chp_link));
434                 link.chpid = chpid;
435                 /* Wait until previous actions have settled. */
436                 css_wait_for_slow_path();
437                 for_each_subchannel_staged(__s390_process_res_acc, NULL,
438                                            &link);
439         }
440 }
441
442 static void __s390_subchannel_vary_chpid(struct subchannel *sch,
443                                          struct chp_id chpid, int on)
444 {
445         unsigned long flags;
446         struct chp_link link;
447
448         memset(&link, 0, sizeof(struct chp_link));
449         link.chpid = chpid;
450         spin_lock_irqsave(sch->lock, flags);
451         if (sch->driver && sch->driver->chp_event)
452                 sch->driver->chp_event(sch, &link,
453                                        on ? CHP_VARY_ON : CHP_VARY_OFF);
454         spin_unlock_irqrestore(sch->lock, flags);
455 }
456
457 static int s390_subchannel_vary_chpid_off(struct subchannel *sch, void *data)
458 {
459         struct chp_id *chpid = data;
460
461         __s390_subchannel_vary_chpid(sch, *chpid, 0);
462         return 0;
463 }
464
465 static int s390_subchannel_vary_chpid_on(struct subchannel *sch, void *data)
466 {
467         struct chp_id *chpid = data;
468
469         __s390_subchannel_vary_chpid(sch, *chpid, 1);
470         return 0;
471 }
472
473 static int
474 __s390_vary_chpid_on(struct subchannel_id schid, void *data)
475 {
476         struct schib schib;
477
478         if (stsch_err(schid, &schib))
479                 /* We're through */
480                 return -ENXIO;
481         /* Put it on the slow path. */
482         css_schedule_eval(schid);
483         return 0;
484 }
485
486 /**
487  * chsc_chp_vary - propagate channel-path vary operation to subchannels
488  * @chpid: channl-path ID
489  * @on: non-zero for vary online, zero for vary offline
490  */
491 int chsc_chp_vary(struct chp_id chpid, int on)
492 {
493         struct chp_link link;
494
495         memset(&link, 0, sizeof(struct chp_link));
496         link.chpid = chpid;
497         /* Wait until previous actions have settled. */
498         css_wait_for_slow_path();
499         /*
500          * Redo PathVerification on the devices the chpid connects to
501          */
502
503         if (on)
504                 for_each_subchannel_staged(s390_subchannel_vary_chpid_on,
505                                            __s390_vary_chpid_on, &link);
506         else
507                 for_each_subchannel_staged(s390_subchannel_vary_chpid_off,
508                                            NULL, &link);
509
510         return 0;
511 }
512
513 static void
514 chsc_remove_cmg_attr(struct channel_subsystem *css)
515 {
516         int i;
517
518         for (i = 0; i <= __MAX_CHPID; i++) {
519                 if (!css->chps[i])
520                         continue;
521                 chp_remove_cmg_attr(css->chps[i]);
522         }
523 }
524
525 static int
526 chsc_add_cmg_attr(struct channel_subsystem *css)
527 {
528         int i, ret;
529
530         ret = 0;
531         for (i = 0; i <= __MAX_CHPID; i++) {
532                 if (!css->chps[i])
533                         continue;
534                 ret = chp_add_cmg_attr(css->chps[i]);
535                 if (ret)
536                         goto cleanup;
537         }
538         return ret;
539 cleanup:
540         for (--i; i >= 0; i--) {
541                 if (!css->chps[i])
542                         continue;
543                 chp_remove_cmg_attr(css->chps[i]);
544         }
545         return ret;
546 }
547
548 static int
549 __chsc_do_secm(struct channel_subsystem *css, int enable, void *page)
550 {
551         struct {
552                 struct chsc_header request;
553                 u32 operation_code : 2;
554                 u32 : 30;
555                 u32 key : 4;
556                 u32 : 28;
557                 u32 zeroes1;
558                 u32 cub_addr1;
559                 u32 zeroes2;
560                 u32 cub_addr2;
561                 u32 reserved[13];
562                 struct chsc_header response;
563                 u32 status : 8;
564                 u32 : 4;
565                 u32 fmt : 4;
566                 u32 : 16;
567         } __attribute__ ((packed)) *secm_area;
568         int ret, ccode;
569
570         secm_area = page;
571         secm_area->request.length = 0x0050;
572         secm_area->request.code = 0x0016;
573
574         secm_area->key = PAGE_DEFAULT_KEY;
575         secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
576         secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
577
578         secm_area->operation_code = enable ? 0 : 1;
579
580         ccode = chsc(secm_area);
581         if (ccode > 0)
582                 return (ccode == 3) ? -ENODEV : -EBUSY;
583
584         switch (secm_area->response.code) {
585         case 0x0102:
586         case 0x0103:
587                 ret = -EINVAL;
588         default:
589                 ret = chsc_error_from_response(secm_area->response.code);
590         }
591         if (ret != 0)
592                 CIO_CRW_EVENT(2, "chsc: secm failed (rc=%04x)\n",
593                               secm_area->response.code);
594         return ret;
595 }
596
597 int
598 chsc_secm(struct channel_subsystem *css, int enable)
599 {
600         void  *secm_area;
601         int ret;
602
603         secm_area = (void *)get_zeroed_page(GFP_KERNEL |  GFP_DMA);
604         if (!secm_area)
605                 return -ENOMEM;
606
607         if (enable && !css->cm_enabled) {
608                 css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
609                 css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
610                 if (!css->cub_addr1 || !css->cub_addr2) {
611                         free_page((unsigned long)css->cub_addr1);
612                         free_page((unsigned long)css->cub_addr2);
613                         free_page((unsigned long)secm_area);
614                         return -ENOMEM;
615                 }
616         }
617         ret = __chsc_do_secm(css, enable, secm_area);
618         if (!ret) {
619                 css->cm_enabled = enable;
620                 if (css->cm_enabled) {
621                         ret = chsc_add_cmg_attr(css);
622                         if (ret) {
623                                 memset(secm_area, 0, PAGE_SIZE);
624                                 __chsc_do_secm(css, 0, secm_area);
625                                 css->cm_enabled = 0;
626                         }
627                 } else
628                         chsc_remove_cmg_attr(css);
629         }
630         if (!css->cm_enabled) {
631                 free_page((unsigned long)css->cub_addr1);
632                 free_page((unsigned long)css->cub_addr2);
633         }
634         free_page((unsigned long)secm_area);
635         return ret;
636 }
637
638 int chsc_determine_channel_path_desc(struct chp_id chpid, int fmt, int rfmt,
639                                      int c, int m,
640                                      struct chsc_response_struct *resp)
641 {
642         int ccode, ret;
643
644         struct {
645                 struct chsc_header request;
646                 u32 : 2;
647                 u32 m : 1;
648                 u32 c : 1;
649                 u32 fmt : 4;
650                 u32 cssid : 8;
651                 u32 : 4;
652                 u32 rfmt : 4;
653                 u32 first_chpid : 8;
654                 u32 : 24;
655                 u32 last_chpid : 8;
656                 u32 zeroes1;
657                 struct chsc_header response;
658                 u8 data[PAGE_SIZE - 20];
659         } __attribute__ ((packed)) *scpd_area;
660
661         if ((rfmt == 1) && !css_general_characteristics.fcs)
662                 return -EINVAL;
663         if ((rfmt == 2) && !css_general_characteristics.cib)
664                 return -EINVAL;
665         scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
666         if (!scpd_area)
667                 return -ENOMEM;
668
669         scpd_area->request.length = 0x0010;
670         scpd_area->request.code = 0x0002;
671
672         scpd_area->cssid = chpid.cssid;
673         scpd_area->first_chpid = chpid.id;
674         scpd_area->last_chpid = chpid.id;
675         scpd_area->m = m;
676         scpd_area->c = c;
677         scpd_area->fmt = fmt;
678         scpd_area->rfmt = rfmt;
679
680         ccode = chsc(scpd_area);
681         if (ccode > 0) {
682                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
683                 goto out;
684         }
685
686         ret = chsc_error_from_response(scpd_area->response.code);
687         if (ret == 0)
688                 /* Success. */
689                 memcpy(resp, &scpd_area->response, scpd_area->response.length);
690         else
691                 CIO_CRW_EVENT(2, "chsc: scpd failed (rc=%04x)\n",
692                               scpd_area->response.code);
693 out:
694         free_page((unsigned long)scpd_area);
695         return ret;
696 }
697 EXPORT_SYMBOL_GPL(chsc_determine_channel_path_desc);
698
699 int chsc_determine_base_channel_path_desc(struct chp_id chpid,
700                                           struct channel_path_desc *desc)
701 {
702         struct chsc_response_struct *chsc_resp;
703         int ret;
704
705         chsc_resp = kzalloc(sizeof(*chsc_resp), GFP_KERNEL);
706         if (!chsc_resp)
707                 return -ENOMEM;
708         ret = chsc_determine_channel_path_desc(chpid, 0, 0, 0, 0, chsc_resp);
709         if (ret)
710                 goto out_free;
711         memcpy(desc, &chsc_resp->data, chsc_resp->length);
712 out_free:
713         kfree(chsc_resp);
714         return ret;
715 }
716
717 static void
718 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
719                           struct cmg_chars *chars)
720 {
721         switch (chp->cmg) {
722         case 2:
723         case 3:
724                 chp->cmg_chars = kmalloc(sizeof(struct cmg_chars),
725                                          GFP_KERNEL);
726                 if (chp->cmg_chars) {
727                         int i, mask;
728                         struct cmg_chars *cmg_chars;
729
730                         cmg_chars = chp->cmg_chars;
731                         for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
732                                 mask = 0x80 >> (i + 3);
733                                 if (cmcv & mask)
734                                         cmg_chars->values[i] = chars->values[i];
735                                 else
736                                         cmg_chars->values[i] = 0;
737                         }
738                 }
739                 break;
740         default:
741                 /* No cmg-dependent data. */
742                 break;
743         }
744 }
745
746 int chsc_get_channel_measurement_chars(struct channel_path *chp)
747 {
748         int ccode, ret;
749
750         struct {
751                 struct chsc_header request;
752                 u32 : 24;
753                 u32 first_chpid : 8;
754                 u32 : 24;
755                 u32 last_chpid : 8;
756                 u32 zeroes1;
757                 struct chsc_header response;
758                 u32 zeroes2;
759                 u32 not_valid : 1;
760                 u32 shared : 1;
761                 u32 : 22;
762                 u32 chpid : 8;
763                 u32 cmcv : 5;
764                 u32 : 11;
765                 u32 cmgq : 8;
766                 u32 cmg : 8;
767                 u32 zeroes3;
768                 u32 data[NR_MEASUREMENT_CHARS];
769         } __attribute__ ((packed)) *scmc_area;
770
771         scmc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
772         if (!scmc_area)
773                 return -ENOMEM;
774
775         scmc_area->request.length = 0x0010;
776         scmc_area->request.code = 0x0022;
777
778         scmc_area->first_chpid = chp->chpid.id;
779         scmc_area->last_chpid = chp->chpid.id;
780
781         ccode = chsc(scmc_area);
782         if (ccode > 0) {
783                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
784                 goto out;
785         }
786
787         ret = chsc_error_from_response(scmc_area->response.code);
788         if (ret == 0) {
789                 /* Success. */
790                 if (!scmc_area->not_valid) {
791                         chp->cmg = scmc_area->cmg;
792                         chp->shared = scmc_area->shared;
793                         chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
794                                                   (struct cmg_chars *)
795                                                   &scmc_area->data);
796                 } else {
797                         chp->cmg = -1;
798                         chp->shared = -1;
799                 }
800         } else {
801                 CIO_CRW_EVENT(2, "chsc: scmc failed (rc=%04x)\n",
802                               scmc_area->response.code);
803         }
804 out:
805         free_page((unsigned long)scmc_area);
806         return ret;
807 }
808
809 int __init chsc_alloc_sei_area(void)
810 {
811         int ret;
812
813         sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
814         if (!sei_page) {
815                 CIO_MSG_EVENT(0, "Can't allocate page for processing of "
816                               "chsc machine checks!\n");
817                 return -ENOMEM;
818         }
819         ret = s390_register_crw_handler(CRW_RSC_CSS, chsc_process_crw);
820         if (ret)
821                 kfree(sei_page);
822         return ret;
823 }
824
825 void __init chsc_free_sei_area(void)
826 {
827         s390_unregister_crw_handler(CRW_RSC_CSS);
828         kfree(sei_page);
829 }
830
831 int __init
832 chsc_enable_facility(int operation_code)
833 {
834         int ret;
835         struct {
836                 struct chsc_header request;
837                 u8 reserved1:4;
838                 u8 format:4;
839                 u8 reserved2;
840                 u16 operation_code;
841                 u32 reserved3;
842                 u32 reserved4;
843                 u32 operation_data_area[252];
844                 struct chsc_header response;
845                 u32 reserved5:4;
846                 u32 format2:4;
847                 u32 reserved6:24;
848         } __attribute__ ((packed)) *sda_area;
849
850         sda_area = (void *)get_zeroed_page(GFP_KERNEL|GFP_DMA);
851         if (!sda_area)
852                 return -ENOMEM;
853         sda_area->request.length = 0x0400;
854         sda_area->request.code = 0x0031;
855         sda_area->operation_code = operation_code;
856
857         ret = chsc(sda_area);
858         if (ret > 0) {
859                 ret = (ret == 3) ? -ENODEV : -EBUSY;
860                 goto out;
861         }
862
863         switch (sda_area->response.code) {
864         case 0x0101:
865                 ret = -EOPNOTSUPP;
866                 break;
867         default:
868                 ret = chsc_error_from_response(sda_area->response.code);
869         }
870         if (ret != 0)
871                 CIO_CRW_EVENT(2, "chsc: sda (oc=%x) failed (rc=%04x)\n",
872                               operation_code, sda_area->response.code);
873  out:
874         free_page((unsigned long)sda_area);
875         return ret;
876 }
877
878 struct css_general_char css_general_characteristics;
879 struct css_chsc_char css_chsc_characteristics;
880
881 int __init
882 chsc_determine_css_characteristics(void)
883 {
884         int result;
885         struct {
886                 struct chsc_header request;
887                 u32 reserved1;
888                 u32 reserved2;
889                 u32 reserved3;
890                 struct chsc_header response;
891                 u32 reserved4;
892                 u32 general_char[510];
893                 u32 chsc_char[518];
894         } __attribute__ ((packed)) *scsc_area;
895
896         scsc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
897         if (!scsc_area)
898                 return -ENOMEM;
899
900         scsc_area->request.length = 0x0010;
901         scsc_area->request.code = 0x0010;
902
903         result = chsc(scsc_area);
904         if (result) {
905                 result = (result == 3) ? -ENODEV : -EBUSY;
906                 goto exit;
907         }
908
909         result = chsc_error_from_response(scsc_area->response.code);
910         if (result == 0) {
911                 memcpy(&css_general_characteristics, scsc_area->general_char,
912                        sizeof(css_general_characteristics));
913                 memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
914                        sizeof(css_chsc_characteristics));
915         } else
916                 CIO_CRW_EVENT(2, "chsc: scsc failed (rc=%04x)\n",
917                               scsc_area->response.code);
918 exit:
919         free_page ((unsigned long) scsc_area);
920         return result;
921 }
922
923 EXPORT_SYMBOL_GPL(css_general_characteristics);
924 EXPORT_SYMBOL_GPL(css_chsc_characteristics);
925
926 int chsc_sstpc(void *page, unsigned int op, u16 ctrl)
927 {
928         struct {
929                 struct chsc_header request;
930                 unsigned int rsvd0;
931                 unsigned int op : 8;
932                 unsigned int rsvd1 : 8;
933                 unsigned int ctrl : 16;
934                 unsigned int rsvd2[5];
935                 struct chsc_header response;
936                 unsigned int rsvd3[7];
937         } __attribute__ ((packed)) *rr;
938         int rc;
939
940         memset(page, 0, PAGE_SIZE);
941         rr = page;
942         rr->request.length = 0x0020;
943         rr->request.code = 0x0033;
944         rr->op = op;
945         rr->ctrl = ctrl;
946         rc = chsc(rr);
947         if (rc)
948                 return -EIO;
949         rc = (rr->response.code == 0x0001) ? 0 : -EIO;
950         return rc;
951 }
952
953 int chsc_sstpi(void *page, void *result, size_t size)
954 {
955         struct {
956                 struct chsc_header request;
957                 unsigned int rsvd0[3];
958                 struct chsc_header response;
959                 char data[size];
960         } __attribute__ ((packed)) *rr;
961         int rc;
962
963         memset(page, 0, PAGE_SIZE);
964         rr = page;
965         rr->request.length = 0x0010;
966         rr->request.code = 0x0038;
967         rc = chsc(rr);
968         if (rc)
969                 return -EIO;
970         memcpy(result, &rr->data, size);
971         return (rr->response.code == 0x0001) ? 0 : -EIO;
972 }
973