Merge master.kernel.org:/pub/scm/linux/kernel/git/kyle/parisc-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 (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
6  *                            IBM Corporation
7  *    Author(s): Ingo Adlung (adlung@de.ibm.com)
8  *               Cornelia Huck (cornelia.huck@de.ibm.com)
9  *               Arnd Bergmann (arndb@de.ibm.com)
10  */
11
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/init.h>
15 #include <linux/device.h>
16
17 #include <asm/cio.h>
18
19 #include "css.h"
20 #include "cio.h"
21 #include "cio_debug.h"
22 #include "ioasm.h"
23 #include "chsc.h"
24
25 static void *sei_page;
26
27 static int new_channel_path(int chpid);
28
29 static inline void
30 set_chp_logically_online(int chp, int onoff)
31 {
32         css[0]->chps[chp]->state = onoff;
33 }
34
35 static int
36 get_chp_status(int chp)
37 {
38         return (css[0]->chps[chp] ? css[0]->chps[chp]->state : -ENODEV);
39 }
40
41 void
42 chsc_validate_chpids(struct subchannel *sch)
43 {
44         int mask, chp;
45
46         for (chp = 0; chp <= 7; chp++) {
47                 mask = 0x80 >> chp;
48                 if (!get_chp_status(sch->schib.pmcw.chpid[chp]))
49                         /* disable using this path */
50                         sch->opm &= ~mask;
51         }
52 }
53
54 void
55 chpid_is_actually_online(int chp)
56 {
57         int state;
58
59         state = get_chp_status(chp);
60         if (state < 0) {
61                 need_rescan = 1;
62                 queue_work(slow_path_wq, &slow_path_work);
63         } else
64                 WARN_ON(!state);
65 }
66
67 /* FIXME: this is _always_ called for every subchannel. shouldn't we
68  *        process more than one at a time? */
69 static int
70 chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
71 {
72         int ccode, j;
73
74         struct {
75                 struct chsc_header request;
76                 u16 reserved1a:10;
77                 u16 ssid:2;
78                 u16 reserved1b:4;
79                 u16 f_sch;        /* first subchannel */
80                 u16 reserved2;
81                 u16 l_sch;        /* last subchannel */
82                 u32 reserved3;
83                 struct chsc_header response;
84                 u32 reserved4;
85                 u8 sch_valid : 1;
86                 u8 dev_valid : 1;
87                 u8 st        : 3; /* subchannel type */
88                 u8 zeroes    : 3;
89                 u8  unit_addr;    /* unit address */
90                 u16 devno;        /* device number */
91                 u8 path_mask;
92                 u8 fla_valid_mask;
93                 u16 sch;          /* subchannel */
94                 u8 chpid[8];      /* chpids 0-7 */
95                 u16 fla[8];       /* full link addresses 0-7 */
96         } __attribute__ ((packed)) *ssd_area;
97
98         ssd_area = page;
99
100         ssd_area->request.length = 0x0010;
101         ssd_area->request.code = 0x0004;
102
103         ssd_area->ssid = sch->schid.ssid;
104         ssd_area->f_sch = sch->schid.sch_no;
105         ssd_area->l_sch = sch->schid.sch_no;
106
107         ccode = chsc(ssd_area);
108         if (ccode > 0) {
109                 pr_debug("chsc returned with ccode = %d\n", ccode);
110                 return (ccode == 3) ? -ENODEV : -EBUSY;
111         }
112
113         switch (ssd_area->response.code) {
114         case 0x0001: /* everything ok */
115                 break;
116         case 0x0002:
117                 CIO_CRW_EVENT(2, "Invalid command!\n");
118                 return -EINVAL;
119         case 0x0003:
120                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
121                 return -EINVAL;
122         case 0x0004:
123                 CIO_CRW_EVENT(2, "Model does not provide ssd\n");
124                 return -EOPNOTSUPP;
125         default:
126                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
127                               ssd_area->response.code);
128                 return -EIO;
129         }
130
131         /*
132          * ssd_area->st stores the type of the detected
133          * subchannel, with the following definitions:
134          *
135          * 0: I/O subchannel:     All fields have meaning
136          * 1: CHSC subchannel:    Only sch_val, st and sch
137          *                        have meaning
138          * 2: Message subchannel: All fields except unit_addr
139          *                        have meaning
140          * 3: ADM subchannel:     Only sch_val, st and sch
141          *                        have meaning
142          *
143          * Other types are currently undefined.
144          */
145         if (ssd_area->st > 3) { /* uhm, that looks strange... */
146                 CIO_CRW_EVENT(0, "Strange subchannel type %d"
147                               " for sch 0.%x.%04x\n", ssd_area->st,
148                               sch->schid.ssid, sch->schid.sch_no);
149                 /*
150                  * There may have been a new subchannel type defined in the
151                  * time since this code was written; since we don't know which
152                  * fields have meaning and what to do with it we just jump out
153                  */
154                 return 0;
155         } else {
156                 const char *type[4] = {"I/O", "chsc", "message", "ADM"};
157                 CIO_CRW_EVENT(6, "ssd: sch 0.%x.%04x is %s subchannel\n",
158                               sch->schid.ssid, sch->schid.sch_no,
159                               type[ssd_area->st]);
160
161                 sch->ssd_info.valid = 1;
162                 sch->ssd_info.type = ssd_area->st;
163         }
164
165         if (ssd_area->st == 0 || ssd_area->st == 2) {
166                 for (j = 0; j < 8; j++) {
167                         if (!((0x80 >> j) & ssd_area->path_mask &
168                               ssd_area->fla_valid_mask))
169                                 continue;
170                         sch->ssd_info.chpid[j] = ssd_area->chpid[j];
171                         sch->ssd_info.fla[j]   = ssd_area->fla[j];
172                 }
173         }
174         return 0;
175 }
176
177 int
178 css_get_ssd_info(struct subchannel *sch)
179 {
180         int ret;
181         void *page;
182
183         page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
184         if (!page)
185                 return -ENOMEM;
186         spin_lock_irq(sch->lock);
187         ret = chsc_get_sch_desc_irq(sch, page);
188         if (ret) {
189                 static int cio_chsc_err_msg;
190                 
191                 if (!cio_chsc_err_msg) {
192                         printk(KERN_ERR
193                                "chsc_get_sch_descriptions:"
194                                " Error %d while doing chsc; "
195                                "processing some machine checks may "
196                                "not work\n", ret);
197                         cio_chsc_err_msg = 1;
198                 }
199         }
200         spin_unlock_irq(sch->lock);
201         free_page((unsigned long)page);
202         if (!ret) {
203                 int j, chpid, mask;
204                 /* Allocate channel path structures, if needed. */
205                 for (j = 0; j < 8; j++) {
206                         mask = 0x80 >> j;
207                         chpid = sch->ssd_info.chpid[j];
208                         if ((sch->schib.pmcw.pim & mask) &&
209                             (get_chp_status(chpid) < 0))
210                             new_channel_path(chpid);
211                 }
212         }
213         return ret;
214 }
215
216 static int
217 s390_subchannel_remove_chpid(struct device *dev, void *data)
218 {
219         int j;
220         int mask;
221         struct subchannel *sch;
222         struct channel_path *chpid;
223         struct schib schib;
224
225         sch = to_subchannel(dev);
226         chpid = data;
227         for (j = 0; j < 8; j++) {
228                 mask = 0x80 >> j;
229                 if ((sch->schib.pmcw.pim & mask) &&
230                     (sch->schib.pmcw.chpid[j] == chpid->id))
231                         break;
232         }
233         if (j >= 8)
234                 return 0;
235
236         spin_lock_irq(sch->lock);
237
238         stsch(sch->schid, &schib);
239         if (!schib.pmcw.dnv)
240                 goto out_unreg;
241         memcpy(&sch->schib, &schib, sizeof(struct schib));
242         /* Check for single path devices. */
243         if (sch->schib.pmcw.pim == 0x80)
244                 goto out_unreg;
245
246         if ((sch->schib.scsw.actl & SCSW_ACTL_DEVACT) &&
247             (sch->schib.scsw.actl & SCSW_ACTL_SCHACT) &&
248             (sch->schib.pmcw.lpum == mask)) {
249                 int cc;
250
251                 cc = cio_clear(sch);
252                 if (cc == -ENODEV)
253                         goto out_unreg;
254                 /* Request retry of internal operation. */
255                 device_set_intretry(sch);
256                 /* Call handler. */
257                 if (sch->driver && sch->driver->termination)
258                         sch->driver->termination(&sch->dev);
259                 goto out_unlock;
260         }
261
262         /* trigger path verification. */
263         if (sch->driver && sch->driver->verify)
264                 sch->driver->verify(&sch->dev);
265         else if (sch->lpm == mask)
266                 goto out_unreg;
267 out_unlock:
268         spin_unlock_irq(sch->lock);
269         return 0;
270 out_unreg:
271         spin_unlock_irq(sch->lock);
272         sch->lpm = 0;
273         if (css_enqueue_subchannel_slow(sch->schid)) {
274                 css_clear_subchannel_slow_list();
275                 need_rescan = 1;
276         }
277         return 0;
278 }
279
280 static void
281 s390_set_chpid_offline( __u8 chpid)
282 {
283         char dbf_txt[15];
284         struct device *dev;
285
286         sprintf(dbf_txt, "chpr%x", chpid);
287         CIO_TRACE_EVENT(2, dbf_txt);
288
289         if (get_chp_status(chpid) <= 0)
290                 return;
291         dev = get_device(&css[0]->chps[chpid]->dev);
292         bus_for_each_dev(&css_bus_type, NULL, to_channelpath(dev),
293                          s390_subchannel_remove_chpid);
294
295         if (need_rescan || css_slow_subchannels_exist())
296                 queue_work(slow_path_wq, &slow_path_work);
297         put_device(dev);
298 }
299
300 struct res_acc_data {
301         struct channel_path *chp;
302         u32 fla_mask;
303         u16 fla;
304 };
305
306 static int
307 s390_process_res_acc_sch(struct res_acc_data *res_data, struct subchannel *sch)
308 {
309         int found;
310         int chp;
311         int ccode;
312         
313         found = 0;
314         for (chp = 0; chp <= 7; chp++)
315                 /*
316                  * check if chpid is in information updated by ssd
317                  */
318                 if (sch->ssd_info.valid &&
319                     sch->ssd_info.chpid[chp] == res_data->chp->id &&
320                     (sch->ssd_info.fla[chp] & res_data->fla_mask)
321                     == res_data->fla) {
322                         found = 1;
323                         break;
324                 }
325         
326         if (found == 0)
327                 return 0;
328
329         /*
330          * Do a stsch to update our subchannel structure with the
331          * new path information and eventually check for logically
332          * offline chpids.
333          */
334         ccode = stsch(sch->schid, &sch->schib);
335         if (ccode > 0)
336                 return 0;
337
338         return 0x80 >> chp;
339 }
340
341 static int
342 s390_process_res_acc_new_sch(struct subchannel_id schid)
343 {
344         struct schib schib;
345         int ret;
346         /*
347          * We don't know the device yet, but since a path
348          * may be available now to the device we'll have
349          * to do recognition again.
350          * Since we don't have any idea about which chpid
351          * that beast may be on we'll have to do a stsch
352          * on all devices, grr...
353          */
354         if (stsch_err(schid, &schib))
355                 /* We're through */
356                 return need_rescan ? -EAGAIN : -ENXIO;
357
358         /* Put it on the slow path. */
359         ret = css_enqueue_subchannel_slow(schid);
360         if (ret) {
361                 css_clear_subchannel_slow_list();
362                 need_rescan = 1;
363                 return -EAGAIN;
364         }
365         return 0;
366 }
367
368 static int
369 __s390_process_res_acc(struct subchannel_id schid, void *data)
370 {
371         int chp_mask, old_lpm;
372         struct res_acc_data *res_data;
373         struct subchannel *sch;
374
375         res_data = data;
376         sch = get_subchannel_by_schid(schid);
377         if (!sch)
378                 /* Check if a subchannel is newly available. */
379                 return s390_process_res_acc_new_sch(schid);
380
381         spin_lock_irq(sch->lock);
382
383         chp_mask = s390_process_res_acc_sch(res_data, sch);
384
385         if (chp_mask == 0) {
386                 spin_unlock_irq(sch->lock);
387                 put_device(&sch->dev);
388                 return 0;
389         }
390         old_lpm = sch->lpm;
391         sch->lpm = ((sch->schib.pmcw.pim &
392                      sch->schib.pmcw.pam &
393                      sch->schib.pmcw.pom)
394                     | chp_mask) & sch->opm;
395         if (!old_lpm && sch->lpm)
396                 device_trigger_reprobe(sch);
397         else if (sch->driver && sch->driver->verify)
398                 sch->driver->verify(&sch->dev);
399
400         spin_unlock_irq(sch->lock);
401         put_device(&sch->dev);
402         return 0;
403 }
404
405
406 static int
407 s390_process_res_acc (struct res_acc_data *res_data)
408 {
409         int rc;
410         char dbf_txt[15];
411
412         sprintf(dbf_txt, "accpr%x", res_data->chp->id);
413         CIO_TRACE_EVENT( 2, dbf_txt);
414         if (res_data->fla != 0) {
415                 sprintf(dbf_txt, "fla%x", res_data->fla);
416                 CIO_TRACE_EVENT( 2, dbf_txt);
417         }
418
419         /*
420          * I/O resources may have become accessible.
421          * Scan through all subchannels that may be concerned and
422          * do a validation on those.
423          * The more information we have (info), the less scanning
424          * will we have to do.
425          */
426         rc = for_each_subchannel(__s390_process_res_acc, res_data);
427         if (css_slow_subchannels_exist())
428                 rc = -EAGAIN;
429         else if (rc != -EAGAIN)
430                 rc = 0;
431         return rc;
432 }
433
434 static int
435 __get_chpid_from_lir(void *data)
436 {
437         struct lir {
438                 u8  iq;
439                 u8  ic;
440                 u16 sci;
441                 /* incident-node descriptor */
442                 u32 indesc[28];
443                 /* attached-node descriptor */
444                 u32 andesc[28];
445                 /* incident-specific information */
446                 u32 isinfo[28];
447         } __attribute__ ((packed)) *lir;
448
449         lir = data;
450         if (!(lir->iq&0x80))
451                 /* NULL link incident record */
452                 return -EINVAL;
453         if (!(lir->indesc[0]&0xc0000000))
454                 /* node descriptor not valid */
455                 return -EINVAL;
456         if (!(lir->indesc[0]&0x10000000))
457                 /* don't handle device-type nodes - FIXME */
458                 return -EINVAL;
459         /* Byte 3 contains the chpid. Could also be CTCA, but we don't care */
460
461         return (u16) (lir->indesc[0]&0x000000ff);
462 }
463
464 struct chsc_sei_area {
465         struct chsc_header request;
466         u32 reserved1;
467         u32 reserved2;
468         u32 reserved3;
469         struct chsc_header response;
470         u32 reserved4;
471         u8  flags;
472         u8  vf;         /* validity flags */
473         u8  rs;         /* reporting source */
474         u8  cc;         /* content code */
475         u16 fla;        /* full link address */
476         u16 rsid;       /* reporting source id */
477         u32 reserved5;
478         u32 reserved6;
479         u8 ccdf[4096 - 16 - 24];        /* content-code dependent field */
480         /* ccdf has to be big enough for a link-incident record */
481 } __attribute__ ((packed));
482
483 static int chsc_process_sei_link_incident(struct chsc_sei_area *sei_area)
484 {
485         int chpid;
486
487         CIO_CRW_EVENT(4, "chsc: link incident (rs=%02x, rs_id=%04x)\n",
488                       sei_area->rs, sei_area->rsid);
489         if (sei_area->rs != 4)
490                 return 0;
491         chpid = __get_chpid_from_lir(sei_area->ccdf);
492         if (chpid < 0)
493                 CIO_CRW_EVENT(4, "chsc: link incident - invalid LIR\n");
494         else
495                 s390_set_chpid_offline(chpid);
496
497         return 0;
498 }
499
500 static int chsc_process_sei_res_acc(struct chsc_sei_area *sei_area)
501 {
502         struct res_acc_data res_data;
503         struct device *dev;
504         int status;
505         int rc;
506
507         CIO_CRW_EVENT(4, "chsc: resource accessibility event (rs=%02x, "
508                       "rs_id=%04x)\n", sei_area->rs, sei_area->rsid);
509         if (sei_area->rs != 4)
510                 return 0;
511         /* allocate a new channel path structure, if needed */
512         status = get_chp_status(sei_area->rsid);
513         if (status < 0)
514                 new_channel_path(sei_area->rsid);
515         else if (!status)
516                 return 0;
517         dev = get_device(&css[0]->chps[sei_area->rsid]->dev);
518         memset(&res_data, 0, sizeof(struct res_acc_data));
519         res_data.chp = to_channelpath(dev);
520         if ((sei_area->vf & 0xc0) != 0) {
521                 res_data.fla = sei_area->fla;
522                 if ((sei_area->vf & 0xc0) == 0xc0)
523                         /* full link address */
524                         res_data.fla_mask = 0xffff;
525                 else
526                         /* link address */
527                         res_data.fla_mask = 0xff00;
528         }
529         rc = s390_process_res_acc(&res_data);
530         put_device(dev);
531
532         return rc;
533 }
534
535 static int chsc_process_sei(struct chsc_sei_area *sei_area)
536 {
537         int rc;
538
539         /* Check if we might have lost some information. */
540         if (sei_area->flags & 0x40)
541                 CIO_CRW_EVENT(2, "chsc: event overflow\n");
542         /* which kind of information was stored? */
543         rc = 0;
544         switch (sei_area->cc) {
545         case 1: /* link incident*/
546                 rc = chsc_process_sei_link_incident(sei_area);
547                 break;
548         case 2: /* i/o resource accessibiliy */
549                 rc = chsc_process_sei_res_acc(sei_area);
550                 break;
551         default: /* other stuff */
552                 CIO_CRW_EVENT(4, "chsc: unhandled sei content code %d\n",
553                               sei_area->cc);
554                 break;
555         }
556
557         return rc;
558 }
559
560 int chsc_process_crw(void)
561 {
562         struct chsc_sei_area *sei_area;
563         int ret;
564         int rc;
565
566         if (!sei_page)
567                 return 0;
568         /* Access to sei_page is serialized through machine check handler
569          * thread, so no need for locking. */
570         sei_area = sei_page;
571
572         CIO_TRACE_EVENT( 2, "prcss");
573         ret = 0;
574         do {
575                 memset(sei_area, 0, sizeof(*sei_area));
576                 sei_area->request.length = 0x0010;
577                 sei_area->request.code = 0x000e;
578                 if (chsc(sei_area))
579                         break;
580
581                 if (sei_area->response.code == 0x0001) {
582                         CIO_CRW_EVENT(4, "chsc: sei successful\n");
583                         rc = chsc_process_sei(sei_area);
584                         if (rc)
585                                 ret = rc;
586                 } else {
587                         CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x)\n",
588                                       sei_area->response.code);
589                         ret = 0;
590                         break;
591                 }
592         } while (sei_area->flags & 0x80);
593
594         return ret;
595 }
596
597 static int
598 __chp_add_new_sch(struct subchannel_id schid)
599 {
600         struct schib schib;
601         int ret;
602
603         if (stsch_err(schid, &schib))
604                 /* We're through */
605                 return need_rescan ? -EAGAIN : -ENXIO;
606
607         /* Put it on the slow path. */
608         ret = css_enqueue_subchannel_slow(schid);
609         if (ret) {
610                 css_clear_subchannel_slow_list();
611                 need_rescan = 1;
612                 return -EAGAIN;
613         }
614         return 0;
615 }
616
617
618 static int
619 __chp_add(struct subchannel_id schid, void *data)
620 {
621         int i, mask;
622         struct channel_path *chp;
623         struct subchannel *sch;
624
625         chp = data;
626         sch = get_subchannel_by_schid(schid);
627         if (!sch)
628                 /* Check if the subchannel is now available. */
629                 return __chp_add_new_sch(schid);
630         spin_lock_irq(sch->lock);
631         for (i=0; i<8; i++) {
632                 mask = 0x80 >> i;
633                 if ((sch->schib.pmcw.pim & mask) &&
634                     (sch->schib.pmcw.chpid[i] == chp->id)) {
635                         if (stsch(sch->schid, &sch->schib) != 0) {
636                                 /* Endgame. */
637                                 spin_unlock_irq(sch->lock);
638                                 return -ENXIO;
639                         }
640                         break;
641                 }
642         }
643         if (i==8) {
644                 spin_unlock_irq(sch->lock);
645                 return 0;
646         }
647         sch->lpm = ((sch->schib.pmcw.pim &
648                      sch->schib.pmcw.pam &
649                      sch->schib.pmcw.pom)
650                     | mask) & sch->opm;
651
652         if (sch->driver && sch->driver->verify)
653                 sch->driver->verify(&sch->dev);
654
655         spin_unlock_irq(sch->lock);
656         put_device(&sch->dev);
657         return 0;
658 }
659
660 static int
661 chp_add(int chpid)
662 {
663         int rc;
664         char dbf_txt[15];
665         struct device *dev;
666
667         if (!get_chp_status(chpid))
668                 return 0; /* no need to do the rest */
669         
670         sprintf(dbf_txt, "cadd%x", chpid);
671         CIO_TRACE_EVENT(2, dbf_txt);
672
673         dev = get_device(&css[0]->chps[chpid]->dev);
674         rc = for_each_subchannel(__chp_add, to_channelpath(dev));
675         if (css_slow_subchannels_exist())
676                 rc = -EAGAIN;
677         if (rc != -EAGAIN)
678                 rc = 0;
679         put_device(dev);
680         return rc;
681 }
682
683 /* 
684  * Handling of crw machine checks with channel path source.
685  */
686 int
687 chp_process_crw(int chpid, int on)
688 {
689         if (on == 0) {
690                 /* Path has gone. We use the link incident routine.*/
691                 s390_set_chpid_offline(chpid);
692                 return 0; /* De-register is async anyway. */
693         }
694         /*
695          * Path has come. Allocate a new channel path structure,
696          * if needed.
697          */
698         if (get_chp_status(chpid) < 0)
699                 new_channel_path(chpid);
700         /* Avoid the extra overhead in process_rec_acc. */
701         return chp_add(chpid);
702 }
703
704 static int check_for_io_on_path(struct subchannel *sch, int index)
705 {
706         int cc;
707
708         cc = stsch(sch->schid, &sch->schib);
709         if (cc)
710                 return 0;
711         if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index))
712                 return 1;
713         return 0;
714 }
715
716 static void terminate_internal_io(struct subchannel *sch)
717 {
718         if (cio_clear(sch)) {
719                 /* Recheck device in case clear failed. */
720                 sch->lpm = 0;
721                 if (device_trigger_verify(sch) != 0) {
722                         if(css_enqueue_subchannel_slow(sch->schid)) {
723                                 css_clear_subchannel_slow_list();
724                                 need_rescan = 1;
725                         }
726                 }
727                 return;
728         }
729         /* Request retry of internal operation. */
730         device_set_intretry(sch);
731         /* Call handler. */
732         if (sch->driver && sch->driver->termination)
733                 sch->driver->termination(&sch->dev);
734 }
735
736 static void
737 __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
738 {
739         int chp, old_lpm;
740         unsigned long flags;
741
742         if (!sch->ssd_info.valid)
743                 return;
744         
745         spin_lock_irqsave(sch->lock, flags);
746         old_lpm = sch->lpm;
747         for (chp = 0; chp < 8; chp++) {
748                 if (sch->ssd_info.chpid[chp] != chpid)
749                         continue;
750
751                 if (on) {
752                         sch->opm |= (0x80 >> chp);
753                         sch->lpm |= (0x80 >> chp);
754                         if (!old_lpm)
755                                 device_trigger_reprobe(sch);
756                         else if (sch->driver && sch->driver->verify)
757                                 sch->driver->verify(&sch->dev);
758                         break;
759                 }
760                 sch->opm &= ~(0x80 >> chp);
761                 sch->lpm &= ~(0x80 >> chp);
762                 if (check_for_io_on_path(sch, chp)) {
763                         if (device_is_online(sch))
764                                 /* Path verification is done after killing. */
765                                 device_kill_io(sch);
766                         else
767                                 /* Kill and retry internal I/O. */
768                                 terminate_internal_io(sch);
769                 } else if (!sch->lpm) {
770                         if (device_trigger_verify(sch) != 0) {
771                                 if (css_enqueue_subchannel_slow(sch->schid)) {
772                                         css_clear_subchannel_slow_list();
773                                         need_rescan = 1;
774                                 }
775                         }
776                 } else if (sch->driver && sch->driver->verify)
777                         sch->driver->verify(&sch->dev);
778                 break;
779         }
780         spin_unlock_irqrestore(sch->lock, flags);
781 }
782
783 static int
784 s390_subchannel_vary_chpid_off(struct device *dev, void *data)
785 {
786         struct subchannel *sch;
787         __u8 *chpid;
788
789         sch = to_subchannel(dev);
790         chpid = data;
791
792         __s390_subchannel_vary_chpid(sch, *chpid, 0);
793         return 0;
794 }
795
796 static int
797 s390_subchannel_vary_chpid_on(struct device *dev, void *data)
798 {
799         struct subchannel *sch;
800         __u8 *chpid;
801
802         sch = to_subchannel(dev);
803         chpid = data;
804
805         __s390_subchannel_vary_chpid(sch, *chpid, 1);
806         return 0;
807 }
808
809 static int
810 __s390_vary_chpid_on(struct subchannel_id schid, void *data)
811 {
812         struct schib schib;
813         struct subchannel *sch;
814
815         sch = get_subchannel_by_schid(schid);
816         if (sch) {
817                 put_device(&sch->dev);
818                 return 0;
819         }
820         if (stsch_err(schid, &schib))
821                 /* We're through */
822                 return -ENXIO;
823         /* Put it on the slow path. */
824         if (css_enqueue_subchannel_slow(schid)) {
825                 css_clear_subchannel_slow_list();
826                 need_rescan = 1;
827                 return -EAGAIN;
828         }
829         return 0;
830 }
831
832 /*
833  * Function: s390_vary_chpid
834  * Varies the specified chpid online or offline
835  */
836 static int
837 s390_vary_chpid( __u8 chpid, int on)
838 {
839         char dbf_text[15];
840         int status;
841
842         sprintf(dbf_text, on?"varyon%x":"varyoff%x", chpid);
843         CIO_TRACE_EVENT( 2, dbf_text);
844
845         status = get_chp_status(chpid);
846         if (status < 0) {
847                 printk(KERN_ERR "Can't vary unknown chpid %02X\n", chpid);
848                 return -EINVAL;
849         }
850
851         if (!on && !status) {
852                 printk(KERN_ERR "chpid %x is already offline\n", chpid);
853                 return -EINVAL;
854         }
855
856         set_chp_logically_online(chpid, on);
857
858         /*
859          * Redo PathVerification on the devices the chpid connects to
860          */
861
862         bus_for_each_dev(&css_bus_type, NULL, &chpid, on ?
863                          s390_subchannel_vary_chpid_on :
864                          s390_subchannel_vary_chpid_off);
865         if (on)
866                 /* Scan for new devices on varied on path. */
867                 for_each_subchannel(__s390_vary_chpid_on, NULL);
868         if (need_rescan || css_slow_subchannels_exist())
869                 queue_work(slow_path_wq, &slow_path_work);
870         return 0;
871 }
872
873 /*
874  * Channel measurement related functions
875  */
876 static ssize_t
877 chp_measurement_chars_read(struct kobject *kobj, char *buf, loff_t off,
878                            size_t count)
879 {
880         struct channel_path *chp;
881         unsigned int size;
882
883         chp = to_channelpath(container_of(kobj, struct device, kobj));
884         if (!chp->cmg_chars)
885                 return 0;
886
887         size = sizeof(struct cmg_chars);
888
889         if (off > size)
890                 return 0;
891         if (off + count > size)
892                 count = size - off;
893         memcpy(buf, chp->cmg_chars + off, count);
894         return count;
895 }
896
897 static struct bin_attribute chp_measurement_chars_attr = {
898         .attr = {
899                 .name = "measurement_chars",
900                 .mode = S_IRUSR,
901                 .owner = THIS_MODULE,
902         },
903         .size = sizeof(struct cmg_chars),
904         .read = chp_measurement_chars_read,
905 };
906
907 static void
908 chp_measurement_copy_block(struct cmg_entry *buf,
909                            struct channel_subsystem *css, int chpid)
910 {
911         void *area;
912         struct cmg_entry *entry, reference_buf;
913         int idx;
914
915         if (chpid < 128) {
916                 area = css->cub_addr1;
917                 idx = chpid;
918         } else {
919                 area = css->cub_addr2;
920                 idx = chpid - 128;
921         }
922         entry = area + (idx * sizeof(struct cmg_entry));
923         do {
924                 memcpy(buf, entry, sizeof(*entry));
925                 memcpy(&reference_buf, entry, sizeof(*entry));
926         } while (reference_buf.values[0] != buf->values[0]);
927 }
928
929 static ssize_t
930 chp_measurement_read(struct kobject *kobj, char *buf, loff_t off, size_t count)
931 {
932         struct channel_path *chp;
933         struct channel_subsystem *css;
934         unsigned int size;
935
936         chp = to_channelpath(container_of(kobj, struct device, kobj));
937         css = to_css(chp->dev.parent);
938
939         size = sizeof(struct cmg_entry);
940
941         /* Only allow single reads. */
942         if (off || count < size)
943                 return 0;
944         chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->id);
945         count = size;
946         return count;
947 }
948
949 static struct bin_attribute chp_measurement_attr = {
950         .attr = {
951                 .name = "measurement",
952                 .mode = S_IRUSR,
953                 .owner = THIS_MODULE,
954         },
955         .size = sizeof(struct cmg_entry),
956         .read = chp_measurement_read,
957 };
958
959 static void
960 chsc_remove_chp_cmg_attr(struct channel_path *chp)
961 {
962         device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
963         device_remove_bin_file(&chp->dev, &chp_measurement_attr);
964 }
965
966 static int
967 chsc_add_chp_cmg_attr(struct channel_path *chp)
968 {
969         int ret;
970
971         ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
972         if (ret)
973                 return ret;
974         ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
975         if (ret)
976                 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
977         return ret;
978 }
979
980 static void
981 chsc_remove_cmg_attr(struct channel_subsystem *css)
982 {
983         int i;
984
985         for (i = 0; i <= __MAX_CHPID; i++) {
986                 if (!css->chps[i])
987                         continue;
988                 chsc_remove_chp_cmg_attr(css->chps[i]);
989         }
990 }
991
992 static int
993 chsc_add_cmg_attr(struct channel_subsystem *css)
994 {
995         int i, ret;
996
997         ret = 0;
998         for (i = 0; i <= __MAX_CHPID; i++) {
999                 if (!css->chps[i])
1000                         continue;
1001                 ret = chsc_add_chp_cmg_attr(css->chps[i]);
1002                 if (ret)
1003                         goto cleanup;
1004         }
1005         return ret;
1006 cleanup:
1007         for (--i; i >= 0; i--) {
1008                 if (!css->chps[i])
1009                         continue;
1010                 chsc_remove_chp_cmg_attr(css->chps[i]);
1011         }
1012         return ret;
1013 }
1014
1015
1016 static int
1017 __chsc_do_secm(struct channel_subsystem *css, int enable, void *page)
1018 {
1019         struct {
1020                 struct chsc_header request;
1021                 u32 operation_code : 2;
1022                 u32 : 30;
1023                 u32 key : 4;
1024                 u32 : 28;
1025                 u32 zeroes1;
1026                 u32 cub_addr1;
1027                 u32 zeroes2;
1028                 u32 cub_addr2;
1029                 u32 reserved[13];
1030                 struct chsc_header response;
1031                 u32 status : 8;
1032                 u32 : 4;
1033                 u32 fmt : 4;
1034                 u32 : 16;
1035         } __attribute__ ((packed)) *secm_area;
1036         int ret, ccode;
1037
1038         secm_area = page;
1039         secm_area->request.length = 0x0050;
1040         secm_area->request.code = 0x0016;
1041
1042         secm_area->key = PAGE_DEFAULT_KEY;
1043         secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
1044         secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
1045
1046         secm_area->operation_code = enable ? 0 : 1;
1047
1048         ccode = chsc(secm_area);
1049         if (ccode > 0)
1050                 return (ccode == 3) ? -ENODEV : -EBUSY;
1051
1052         switch (secm_area->response.code) {
1053         case 0x0001: /* Success. */
1054                 ret = 0;
1055                 break;
1056         case 0x0003: /* Invalid block. */
1057         case 0x0007: /* Invalid format. */
1058         case 0x0008: /* Other invalid block. */
1059                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1060                 ret = -EINVAL;
1061                 break;
1062         case 0x0004: /* Command not provided in model. */
1063                 CIO_CRW_EVENT(2, "Model does not provide secm\n");
1064                 ret = -EOPNOTSUPP;
1065                 break;
1066         case 0x0102: /* cub adresses incorrect */
1067                 CIO_CRW_EVENT(2, "Invalid addresses in chsc request block\n");
1068                 ret = -EINVAL;
1069                 break;
1070         case 0x0103: /* key error */
1071                 CIO_CRW_EVENT(2, "Access key error in secm\n");
1072                 ret = -EINVAL;
1073                 break;
1074         case 0x0105: /* error while starting */
1075                 CIO_CRW_EVENT(2, "Error while starting channel measurement\n");
1076                 ret = -EIO;
1077                 break;
1078         default:
1079                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1080                               secm_area->response.code);
1081                 ret = -EIO;
1082         }
1083         return ret;
1084 }
1085
1086 int
1087 chsc_secm(struct channel_subsystem *css, int enable)
1088 {
1089         void  *secm_area;
1090         int ret;
1091
1092         secm_area = (void *)get_zeroed_page(GFP_KERNEL |  GFP_DMA);
1093         if (!secm_area)
1094                 return -ENOMEM;
1095
1096         mutex_lock(&css->mutex);
1097         if (enable && !css->cm_enabled) {
1098                 css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1099                 css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1100                 if (!css->cub_addr1 || !css->cub_addr2) {
1101                         free_page((unsigned long)css->cub_addr1);
1102                         free_page((unsigned long)css->cub_addr2);
1103                         free_page((unsigned long)secm_area);
1104                         mutex_unlock(&css->mutex);
1105                         return -ENOMEM;
1106                 }
1107         }
1108         ret = __chsc_do_secm(css, enable, secm_area);
1109         if (!ret) {
1110                 css->cm_enabled = enable;
1111                 if (css->cm_enabled) {
1112                         ret = chsc_add_cmg_attr(css);
1113                         if (ret) {
1114                                 memset(secm_area, 0, PAGE_SIZE);
1115                                 __chsc_do_secm(css, 0, secm_area);
1116                                 css->cm_enabled = 0;
1117                         }
1118                 } else
1119                         chsc_remove_cmg_attr(css);
1120         }
1121         if (enable && !css->cm_enabled) {
1122                 free_page((unsigned long)css->cub_addr1);
1123                 free_page((unsigned long)css->cub_addr2);
1124         }
1125         mutex_unlock(&css->mutex);
1126         free_page((unsigned long)secm_area);
1127         return ret;
1128 }
1129
1130 /*
1131  * Files for the channel path entries.
1132  */
1133 static ssize_t
1134 chp_status_show(struct device *dev, struct device_attribute *attr, char *buf)
1135 {
1136         struct channel_path *chp = container_of(dev, struct channel_path, dev);
1137
1138         if (!chp)
1139                 return 0;
1140         return (get_chp_status(chp->id) ? sprintf(buf, "online\n") :
1141                 sprintf(buf, "offline\n"));
1142 }
1143
1144 static ssize_t
1145 chp_status_write(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
1146 {
1147         struct channel_path *cp = container_of(dev, struct channel_path, dev);
1148         char cmd[10];
1149         int num_args;
1150         int error;
1151
1152         num_args = sscanf(buf, "%5s", cmd);
1153         if (!num_args)
1154                 return count;
1155
1156         if (!strnicmp(cmd, "on", 2))
1157                 error = s390_vary_chpid(cp->id, 1);
1158         else if (!strnicmp(cmd, "off", 3))
1159                 error = s390_vary_chpid(cp->id, 0);
1160         else
1161                 error = -EINVAL;
1162
1163         return error < 0 ? error : count;
1164
1165 }
1166
1167 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
1168
1169 static ssize_t
1170 chp_type_show(struct device *dev, struct device_attribute *attr, char *buf)
1171 {
1172         struct channel_path *chp = container_of(dev, struct channel_path, dev);
1173
1174         if (!chp)
1175                 return 0;
1176         return sprintf(buf, "%x\n", chp->desc.desc);
1177 }
1178
1179 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
1180
1181 static ssize_t
1182 chp_cmg_show(struct device *dev, struct device_attribute *attr, char *buf)
1183 {
1184         struct channel_path *chp = to_channelpath(dev);
1185
1186         if (!chp)
1187                 return 0;
1188         if (chp->cmg == -1) /* channel measurements not available */
1189                 return sprintf(buf, "unknown\n");
1190         return sprintf(buf, "%x\n", chp->cmg);
1191 }
1192
1193 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
1194
1195 static ssize_t
1196 chp_shared_show(struct device *dev, struct device_attribute *attr, char *buf)
1197 {
1198         struct channel_path *chp = to_channelpath(dev);
1199
1200         if (!chp)
1201                 return 0;
1202         if (chp->shared == -1) /* channel measurements not available */
1203                 return sprintf(buf, "unknown\n");
1204         return sprintf(buf, "%x\n", chp->shared);
1205 }
1206
1207 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
1208
1209 static struct attribute * chp_attrs[] = {
1210         &dev_attr_status.attr,
1211         &dev_attr_type.attr,
1212         &dev_attr_cmg.attr,
1213         &dev_attr_shared.attr,
1214         NULL,
1215 };
1216
1217 static struct attribute_group chp_attr_group = {
1218         .attrs = chp_attrs,
1219 };
1220
1221 static void
1222 chp_release(struct device *dev)
1223 {
1224         struct channel_path *cp;
1225         
1226         cp = container_of(dev, struct channel_path, dev);
1227         kfree(cp);
1228 }
1229
1230 static int
1231 chsc_determine_channel_path_description(int chpid,
1232                                         struct channel_path_desc *desc)
1233 {
1234         int ccode, ret;
1235
1236         struct {
1237                 struct chsc_header request;
1238                 u32 : 24;
1239                 u32 first_chpid : 8;
1240                 u32 : 24;
1241                 u32 last_chpid : 8;
1242                 u32 zeroes1;
1243                 struct chsc_header response;
1244                 u32 zeroes2;
1245                 struct channel_path_desc desc;
1246         } __attribute__ ((packed)) *scpd_area;
1247
1248         scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1249         if (!scpd_area)
1250                 return -ENOMEM;
1251
1252         scpd_area->request.length = 0x0010;
1253         scpd_area->request.code = 0x0002;
1254
1255         scpd_area->first_chpid = chpid;
1256         scpd_area->last_chpid = chpid;
1257
1258         ccode = chsc(scpd_area);
1259         if (ccode > 0) {
1260                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1261                 goto out;
1262         }
1263
1264         switch (scpd_area->response.code) {
1265         case 0x0001: /* Success. */
1266                 memcpy(desc, &scpd_area->desc,
1267                        sizeof(struct channel_path_desc));
1268                 ret = 0;
1269                 break;
1270         case 0x0003: /* Invalid block. */
1271         case 0x0007: /* Invalid format. */
1272         case 0x0008: /* Other invalid block. */
1273                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1274                 ret = -EINVAL;
1275                 break;
1276         case 0x0004: /* Command not provided in model. */
1277                 CIO_CRW_EVENT(2, "Model does not provide scpd\n");
1278                 ret = -EOPNOTSUPP;
1279                 break;
1280         default:
1281                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1282                               scpd_area->response.code);
1283                 ret = -EIO;
1284         }
1285 out:
1286         free_page((unsigned long)scpd_area);
1287         return ret;
1288 }
1289
1290 static void
1291 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
1292                           struct cmg_chars *chars)
1293 {
1294         switch (chp->cmg) {
1295         case 2:
1296         case 3:
1297                 chp->cmg_chars = kmalloc(sizeof(struct cmg_chars),
1298                                          GFP_KERNEL);
1299                 if (chp->cmg_chars) {
1300                         int i, mask;
1301                         struct cmg_chars *cmg_chars;
1302
1303                         cmg_chars = chp->cmg_chars;
1304                         for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
1305                                 mask = 0x80 >> (i + 3);
1306                                 if (cmcv & mask)
1307                                         cmg_chars->values[i] = chars->values[i];
1308                                 else
1309                                         cmg_chars->values[i] = 0;
1310                         }
1311                 }
1312                 break;
1313         default:
1314                 /* No cmg-dependent data. */
1315                 break;
1316         }
1317 }
1318
1319 static int
1320 chsc_get_channel_measurement_chars(struct channel_path *chp)
1321 {
1322         int ccode, ret;
1323
1324         struct {
1325                 struct chsc_header request;
1326                 u32 : 24;
1327                 u32 first_chpid : 8;
1328                 u32 : 24;
1329                 u32 last_chpid : 8;
1330                 u32 zeroes1;
1331                 struct chsc_header response;
1332                 u32 zeroes2;
1333                 u32 not_valid : 1;
1334                 u32 shared : 1;
1335                 u32 : 22;
1336                 u32 chpid : 8;
1337                 u32 cmcv : 5;
1338                 u32 : 11;
1339                 u32 cmgq : 8;
1340                 u32 cmg : 8;
1341                 u32 zeroes3;
1342                 u32 data[NR_MEASUREMENT_CHARS];
1343         } __attribute__ ((packed)) *scmc_area;
1344
1345         scmc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1346         if (!scmc_area)
1347                 return -ENOMEM;
1348
1349         scmc_area->request.length = 0x0010;
1350         scmc_area->request.code = 0x0022;
1351
1352         scmc_area->first_chpid = chp->id;
1353         scmc_area->last_chpid = chp->id;
1354
1355         ccode = chsc(scmc_area);
1356         if (ccode > 0) {
1357                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
1358                 goto out;
1359         }
1360
1361         switch (scmc_area->response.code) {
1362         case 0x0001: /* Success. */
1363                 if (!scmc_area->not_valid) {
1364                         chp->cmg = scmc_area->cmg;
1365                         chp->shared = scmc_area->shared;
1366                         chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
1367                                                   (struct cmg_chars *)
1368                                                   &scmc_area->data);
1369                 } else {
1370                         chp->cmg = -1;
1371                         chp->shared = -1;
1372                 }
1373                 ret = 0;
1374                 break;
1375         case 0x0003: /* Invalid block. */
1376         case 0x0007: /* Invalid format. */
1377         case 0x0008: /* Invalid bit combination. */
1378                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
1379                 ret = -EINVAL;
1380                 break;
1381         case 0x0004: /* Command not provided. */
1382                 CIO_CRW_EVENT(2, "Model does not provide scmc\n");
1383                 ret = -EOPNOTSUPP;
1384                 break;
1385         default:
1386                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
1387                               scmc_area->response.code);
1388                 ret = -EIO;
1389         }
1390 out:
1391         free_page((unsigned long)scmc_area);
1392         return ret;
1393 }
1394
1395 /*
1396  * Entries for chpids on the system bus.
1397  * This replaces /proc/chpids.
1398  */
1399 static int
1400 new_channel_path(int chpid)
1401 {
1402         struct channel_path *chp;
1403         int ret;
1404
1405         chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
1406         if (!chp)
1407                 return -ENOMEM;
1408
1409         /* fill in status, etc. */
1410         chp->id = chpid;
1411         chp->state = 1;
1412         chp->dev.parent = &css[0]->device;
1413         chp->dev.release = chp_release;
1414         snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp0.%x", chpid);
1415
1416         /* Obtain channel path description and fill it in. */
1417         ret = chsc_determine_channel_path_description(chpid, &chp->desc);
1418         if (ret)
1419                 goto out_free;
1420         /* Get channel-measurement characteristics. */
1421         if (css_characteristics_avail && css_chsc_characteristics.scmc
1422             && css_chsc_characteristics.secm) {
1423                 ret = chsc_get_channel_measurement_chars(chp);
1424                 if (ret)
1425                         goto out_free;
1426         } else {
1427                 static int msg_done;
1428
1429                 if (!msg_done) {
1430                         printk(KERN_WARNING "cio: Channel measurements not "
1431                                "available, continuing.\n");
1432                         msg_done = 1;
1433                 }
1434                 chp->cmg = -1;
1435         }
1436
1437         /* make it known to the system */
1438         ret = device_register(&chp->dev);
1439         if (ret) {
1440                 printk(KERN_WARNING "%s: could not register %02x\n",
1441                        __func__, chpid);
1442                 goto out_free;
1443         }
1444         ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
1445         if (ret) {
1446                 device_unregister(&chp->dev);
1447                 goto out_free;
1448         }
1449         mutex_lock(&css[0]->mutex);
1450         if (css[0]->cm_enabled) {
1451                 ret = chsc_add_chp_cmg_attr(chp);
1452                 if (ret) {
1453                         sysfs_remove_group(&chp->dev.kobj, &chp_attr_group);
1454                         device_unregister(&chp->dev);
1455                         mutex_unlock(&css[0]->mutex);
1456                         goto out_free;
1457                 }
1458         }
1459         css[0]->chps[chpid] = chp;
1460         mutex_unlock(&css[0]->mutex);
1461         return ret;
1462 out_free:
1463         kfree(chp);
1464         return ret;
1465 }
1466
1467 void *
1468 chsc_get_chp_desc(struct subchannel *sch, int chp_no)
1469 {
1470         struct channel_path *chp;
1471         struct channel_path_desc *desc;
1472
1473         chp = css[0]->chps[sch->schib.pmcw.chpid[chp_no]];
1474         if (!chp)
1475                 return NULL;
1476         desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
1477         if (!desc)
1478                 return NULL;
1479         memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
1480         return desc;
1481 }
1482
1483 static int __init
1484 chsc_alloc_sei_area(void)
1485 {
1486         sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1487         if (!sei_page)
1488                 printk(KERN_WARNING"Can't allocate page for processing of " \
1489                        "chsc machine checks!\n");
1490         return (sei_page ? 0 : -ENOMEM);
1491 }
1492
1493 int __init
1494 chsc_enable_facility(int operation_code)
1495 {
1496         int ret;
1497         struct {
1498                 struct chsc_header request;
1499                 u8 reserved1:4;
1500                 u8 format:4;
1501                 u8 reserved2;
1502                 u16 operation_code;
1503                 u32 reserved3;
1504                 u32 reserved4;
1505                 u32 operation_data_area[252];
1506                 struct chsc_header response;
1507                 u32 reserved5:4;
1508                 u32 format2:4;
1509                 u32 reserved6:24;
1510         } __attribute__ ((packed)) *sda_area;
1511
1512         sda_area = (void *)get_zeroed_page(GFP_KERNEL|GFP_DMA);
1513         if (!sda_area)
1514                 return -ENOMEM;
1515         sda_area->request.length = 0x0400;
1516         sda_area->request.code = 0x0031;
1517         sda_area->operation_code = operation_code;
1518
1519         ret = chsc(sda_area);
1520         if (ret > 0) {
1521                 ret = (ret == 3) ? -ENODEV : -EBUSY;
1522                 goto out;
1523         }
1524         switch (sda_area->response.code) {
1525         case 0x0001: /* everything ok */
1526                 ret = 0;
1527                 break;
1528         case 0x0003: /* invalid request block */
1529         case 0x0007:
1530                 ret = -EINVAL;
1531                 break;
1532         case 0x0004: /* command not provided */
1533         case 0x0101: /* facility not provided */
1534                 ret = -EOPNOTSUPP;
1535                 break;
1536         default: /* something went wrong */
1537                 ret = -EIO;
1538         }
1539  out:
1540         free_page((unsigned long)sda_area);
1541         return ret;
1542 }
1543
1544 subsys_initcall(chsc_alloc_sei_area);
1545
1546 struct css_general_char css_general_characteristics;
1547 struct css_chsc_char css_chsc_characteristics;
1548
1549 int __init
1550 chsc_determine_css_characteristics(void)
1551 {
1552         int result;
1553         struct {
1554                 struct chsc_header request;
1555                 u32 reserved1;
1556                 u32 reserved2;
1557                 u32 reserved3;
1558                 struct chsc_header response;
1559                 u32 reserved4;
1560                 u32 general_char[510];
1561                 u32 chsc_char[518];
1562         } __attribute__ ((packed)) *scsc_area;
1563
1564         scsc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1565         if (!scsc_area) {
1566                 printk(KERN_WARNING"cio: Was not able to determine available" \
1567                        "CHSCs due to no memory.\n");
1568                 return -ENOMEM;
1569         }
1570
1571         scsc_area->request.length = 0x0010;
1572         scsc_area->request.code = 0x0010;
1573
1574         result = chsc(scsc_area);
1575         if (result) {
1576                 printk(KERN_WARNING"cio: Was not able to determine " \
1577                        "available CHSCs, cc=%i.\n", result);
1578                 result = -EIO;
1579                 goto exit;
1580         }
1581
1582         if (scsc_area->response.code != 1) {
1583                 printk(KERN_WARNING"cio: Was not able to determine " \
1584                        "available CHSCs.\n");
1585                 result = -EIO;
1586                 goto exit;
1587         }
1588         memcpy(&css_general_characteristics, scsc_area->general_char,
1589                sizeof(css_general_characteristics));
1590         memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1591                sizeof(css_chsc_characteristics));
1592 exit:
1593         free_page ((unsigned long) scsc_area);
1594         return result;
1595 }
1596
1597 EXPORT_SYMBOL_GPL(css_general_characteristics);
1598 EXPORT_SYMBOL_GPL(css_chsc_characteristics);