Merge master.kernel.org:/home/rmk/linux-2.6-arm-smp
[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  *   $Revision: 1.120 $
5  *
6  *    Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
7  *                            IBM Corporation
8  *    Author(s): Ingo Adlung (adlung@de.ibm.com)
9  *               Cornelia Huck (cohuck@de.ibm.com)
10  *               Arnd Bergmann (arndb@de.ibm.com)
11  */
12
13 #include <linux/module.h>
14 #include <linux/config.h>
15 #include <linux/slab.h>
16 #include <linux/init.h>
17 #include <linux/device.h>
18
19 #include <asm/cio.h>
20
21 #include "css.h"
22 #include "cio.h"
23 #include "cio_debug.h"
24 #include "ioasm.h"
25 #include "chsc.h"
26
27 static struct channel_path *chps[NR_CHPIDS];
28
29 static void *sei_page;
30
31 static int new_channel_path(int chpid);
32
33 static inline void
34 set_chp_logically_online(int chp, int onoff)
35 {
36         chps[chp]->state = onoff;
37 }
38
39 static int
40 get_chp_status(int chp)
41 {
42         return (chps[chp] ? chps[chp]->state : -ENODEV);
43 }
44
45 void
46 chsc_validate_chpids(struct subchannel *sch)
47 {
48         int mask, chp;
49
50         for (chp = 0; chp <= 7; chp++) {
51                 mask = 0x80 >> chp;
52                 if (!get_chp_status(sch->schib.pmcw.chpid[chp]))
53                         /* disable using this path */
54                         sch->opm &= ~mask;
55         }
56 }
57
58 void
59 chpid_is_actually_online(int chp)
60 {
61         int state;
62
63         state = get_chp_status(chp);
64         if (state < 0) {
65                 need_rescan = 1;
66                 queue_work(slow_path_wq, &slow_path_work);
67         } else
68                 WARN_ON(!state);
69 }
70
71 /* FIXME: this is _always_ called for every subchannel. shouldn't we
72  *        process more than one at a time? */
73 static int
74 chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
75 {
76         int ccode, j;
77
78         struct {
79                 struct chsc_header request;
80                 u16 reserved1;
81                 u16 f_sch;        /* first subchannel */
82                 u16 reserved2;
83                 u16 l_sch;        /* last subchannel */
84                 u32 reserved3;
85                 struct chsc_header response;
86                 u32 reserved4;
87                 u8 sch_valid : 1;
88                 u8 dev_valid : 1;
89                 u8 st        : 3; /* subchannel type */
90                 u8 zeroes    : 3;
91                 u8  unit_addr;    /* unit address */
92                 u16 devno;        /* device number */
93                 u8 path_mask;
94                 u8 fla_valid_mask;
95                 u16 sch;          /* subchannel */
96                 u8 chpid[8];      /* chpids 0-7 */
97                 u16 fla[8];       /* full link addresses 0-7 */
98         } *ssd_area;
99
100         ssd_area = page;
101
102         ssd_area->request = (struct chsc_header) {
103                 .length = 0x0010,
104                 .code   = 0x0004,
105         };
106
107         ssd_area->f_sch = sch->irq;
108         ssd_area->l_sch = sch->irq;
109
110         ccode = chsc(ssd_area);
111         if (ccode > 0) {
112                 pr_debug("chsc returned with ccode = %d\n", ccode);
113                 return (ccode == 3) ? -ENODEV : -EBUSY;
114         }
115
116         switch (ssd_area->response.code) {
117         case 0x0001: /* everything ok */
118                 break;
119         case 0x0002:
120                 CIO_CRW_EVENT(2, "Invalid command!\n");
121                 return -EINVAL;
122         case 0x0003:
123                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
124                 return -EINVAL;
125         case 0x0004:
126                 CIO_CRW_EVENT(2, "Model does not provide ssd\n");
127                 return -EOPNOTSUPP;
128         default:
129                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
130                               ssd_area->response.code);
131                 return -EIO;
132         }
133
134         /*
135          * ssd_area->st stores the type of the detected
136          * subchannel, with the following definitions:
137          *
138          * 0: I/O subchannel:     All fields have meaning
139          * 1: CHSC subchannel:    Only sch_val, st and sch
140          *                        have meaning
141          * 2: Message subchannel: All fields except unit_addr
142          *                        have meaning
143          * 3: ADM subchannel:     Only sch_val, st and sch
144          *                        have meaning
145          *
146          * Other types are currently undefined.
147          */
148         if (ssd_area->st > 3) { /* uhm, that looks strange... */
149                 CIO_CRW_EVENT(0, "Strange subchannel type %d"
150                               " for sch %04x\n", ssd_area->st, sch->irq);
151                 /*
152                  * There may have been a new subchannel type defined in the
153                  * time since this code was written; since we don't know which
154                  * fields have meaning and what to do with it we just jump out
155                  */
156                 return 0;
157         } else {
158                 const char *type[4] = {"I/O", "chsc", "message", "ADM"};
159                 CIO_CRW_EVENT(6, "ssd: sch %04x is %s subchannel\n",
160                               sch->irq, type[ssd_area->st]);
161
162                 sch->ssd_info.valid = 1;
163                 sch->ssd_info.type = ssd_area->st;
164         }
165
166         if (ssd_area->st == 0 || ssd_area->st == 2) {
167                 for (j = 0; j < 8; j++) {
168                         if (!((0x80 >> j) & ssd_area->path_mask &
169                               ssd_area->fla_valid_mask))
170                                 continue;
171                         sch->ssd_info.chpid[j] = ssd_area->chpid[j];
172                         sch->ssd_info.fla[j]   = ssd_area->fla[j];
173                 }
174         }
175         return 0;
176 }
177
178 int
179 css_get_ssd_info(struct subchannel *sch)
180 {
181         int ret;
182         void *page;
183
184         page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
185         if (!page)
186                 return -ENOMEM;
187         spin_lock_irq(&sch->lock);
188         ret = chsc_get_sch_desc_irq(sch, page);
189         if (ret) {
190                 static int cio_chsc_err_msg;
191                 
192                 if (!cio_chsc_err_msg) {
193                         printk(KERN_ERR
194                                "chsc_get_sch_descriptions:"
195                                " Error %d while doing chsc; "
196                                "processing some machine checks may "
197                                "not work\n", ret);
198                         cio_chsc_err_msg = 1;
199                 }
200         }
201         spin_unlock_irq(&sch->lock);
202         free_page((unsigned long)page);
203         if (!ret) {
204                 int j, chpid;
205                 /* Allocate channel path structures, if needed. */
206                 for (j = 0; j < 8; j++) {
207                         chpid = sch->ssd_info.chpid[j];
208                         if (chpid && (get_chp_status(chpid) < 0))
209                             new_channel_path(chpid);
210                 }
211         }
212         return ret;
213 }
214
215 static int
216 s390_subchannel_remove_chpid(struct device *dev, void *data)
217 {
218         int j;
219         int mask;
220         struct subchannel *sch;
221         __u8 *chpid;
222         struct schib schib;
223
224         sch = to_subchannel(dev);
225         chpid = data;
226         for (j = 0; j < 8; j++)
227                 if (sch->schib.pmcw.chpid[j] == *chpid)
228                         break;
229         if (j >= 8)
230                 return 0;
231
232         mask = 0x80 >> j;
233         spin_lock(&sch->lock);
234
235         stsch(sch->irq, &schib);
236         if (!schib.pmcw.dnv)
237                 goto out_unreg;
238         memcpy(&sch->schib, &schib, sizeof(struct schib));
239         /* Check for single path devices. */
240         if (sch->schib.pmcw.pim == 0x80)
241                 goto out_unreg;
242         if (sch->vpm == mask)
243                 goto out_unreg;
244
245         if ((sch->schib.scsw.actl & (SCSW_ACTL_CLEAR_PEND |
246                                      SCSW_ACTL_HALT_PEND |
247                                      SCSW_ACTL_START_PEND |
248                                      SCSW_ACTL_RESUME_PEND)) &&
249             (sch->schib.pmcw.lpum == mask)) {
250                 int cc = cio_cancel(sch);
251                 
252                 if (cc == -ENODEV)
253                         goto out_unreg;
254
255                 if (cc == -EINVAL) {
256                         cc = cio_clear(sch);
257                         if (cc == -ENODEV)
258                                 goto out_unreg;
259                         /* Call handler. */
260                         if (sch->driver && sch->driver->termination)
261                                 sch->driver->termination(&sch->dev);
262                         goto out_unlock;
263                 }
264         } else if ((sch->schib.scsw.actl & SCSW_ACTL_DEVACT) &&
265                    (sch->schib.scsw.actl & SCSW_ACTL_SCHACT) &&
266                    (sch->schib.pmcw.lpum == mask)) {
267                 int cc;
268
269                 cc = cio_clear(sch);
270                 if (cc == -ENODEV)
271                         goto out_unreg;
272                 /* Call handler. */
273                 if (sch->driver && sch->driver->termination)
274                         sch->driver->termination(&sch->dev);
275                 goto out_unlock;
276         }
277
278         /* trigger path verification. */
279         if (sch->driver && sch->driver->verify)
280                 sch->driver->verify(&sch->dev);
281 out_unlock:
282         spin_unlock(&sch->lock);
283         return 0;
284 out_unreg:
285         spin_unlock(&sch->lock);
286         sch->lpm = 0;
287         if (css_enqueue_subchannel_slow(sch->irq)) {
288                 css_clear_subchannel_slow_list();
289                 need_rescan = 1;
290         }
291         return 0;
292 }
293
294 static inline void
295 s390_set_chpid_offline( __u8 chpid)
296 {
297         char dbf_txt[15];
298
299         sprintf(dbf_txt, "chpr%x", chpid);
300         CIO_TRACE_EVENT(2, dbf_txt);
301
302         if (get_chp_status(chpid) <= 0)
303                 return;
304
305         bus_for_each_dev(&css_bus_type, NULL, &chpid,
306                          s390_subchannel_remove_chpid);
307
308         if (need_rescan || css_slow_subchannels_exist())
309                 queue_work(slow_path_wq, &slow_path_work);
310 }
311
312 static int
313 s390_process_res_acc_sch(u8 chpid, __u16 fla, u32 fla_mask,
314                          struct subchannel *sch)
315 {
316         int found;
317         int chp;
318         int ccode;
319         
320         found = 0;
321         for (chp = 0; chp <= 7; chp++)
322                 /*
323                  * check if chpid is in information updated by ssd
324                  */
325                 if (sch->ssd_info.valid &&
326                     sch->ssd_info.chpid[chp] == chpid &&
327                     (sch->ssd_info.fla[chp] & fla_mask) == fla) {
328                         found = 1;
329                         break;
330                 }
331         
332         if (found == 0)
333                 return 0;
334
335         /*
336          * Do a stsch to update our subchannel structure with the
337          * new path information and eventually check for logically
338          * offline chpids.
339          */
340         ccode = stsch(sch->irq, &sch->schib);
341         if (ccode > 0)
342                 return 0;
343
344         return 0x80 >> chp;
345 }
346
347 static int
348 s390_process_res_acc (u8 chpid, __u16 fla, u32 fla_mask)
349 {
350         struct subchannel *sch;
351         int irq, rc;
352         char dbf_txt[15];
353
354         sprintf(dbf_txt, "accpr%x", chpid);
355         CIO_TRACE_EVENT( 2, dbf_txt);
356         if (fla != 0) {
357                 sprintf(dbf_txt, "fla%x", fla);
358                 CIO_TRACE_EVENT( 2, dbf_txt);
359         }
360
361         /*
362          * I/O resources may have become accessible.
363          * Scan through all subchannels that may be concerned and
364          * do a validation on those.
365          * The more information we have (info), the less scanning
366          * will we have to do.
367          */
368
369         if (!get_chp_status(chpid))
370                 return 0; /* no need to do the rest */
371
372         rc = 0;
373         for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
374                 int chp_mask, old_lpm;
375
376                 sch = get_subchannel_by_schid(irq);
377                 if (!sch) {
378                         struct schib schib;
379                         int ret;
380                         /*
381                          * We don't know the device yet, but since a path
382                          * may be available now to the device we'll have
383                          * to do recognition again.
384                          * Since we don't have any idea about which chpid
385                          * that beast may be on we'll have to do a stsch
386                          * on all devices, grr...
387                          */
388                         if (stsch(irq, &schib)) {
389                                 /* We're through */
390                                 if (need_rescan)
391                                         rc = -EAGAIN;
392                                 break;
393                         }
394                         if (need_rescan) {
395                                 rc = -EAGAIN;
396                                 continue;
397                         }
398                         /* Put it on the slow path. */
399                         ret = css_enqueue_subchannel_slow(irq);
400                         if (ret) {
401                                 css_clear_subchannel_slow_list();
402                                 need_rescan = 1;
403                         }
404                         rc = -EAGAIN;
405                         continue;
406                 }
407         
408                 spin_lock_irq(&sch->lock);
409
410                 chp_mask = s390_process_res_acc_sch(chpid, fla, fla_mask, sch);
411
412                 if (chp_mask == 0) {
413
414                         spin_unlock_irq(&sch->lock);
415                         continue;
416                 }
417                 old_lpm = sch->lpm;
418                 sch->lpm = ((sch->schib.pmcw.pim &
419                              sch->schib.pmcw.pam &
420                              sch->schib.pmcw.pom)
421                             | chp_mask) & sch->opm;
422                 if (!old_lpm && sch->lpm)
423                         device_trigger_reprobe(sch);
424                 else if (sch->driver && sch->driver->verify)
425                         sch->driver->verify(&sch->dev);
426
427                 spin_unlock_irq(&sch->lock);
428                 put_device(&sch->dev);
429                 if (fla_mask == 0xffff)
430                         break;
431         }
432         return rc;
433 }
434
435 static int
436 __get_chpid_from_lir(void *data)
437 {
438         struct lir {
439                 u8  iq;
440                 u8  ic;
441                 u16 sci;
442                 /* incident-node descriptor */
443                 u32 indesc[28];
444                 /* attached-node descriptor */
445                 u32 andesc[28];
446                 /* incident-specific information */
447                 u32 isinfo[28];
448         } *lir;
449
450         lir = (struct lir*) data;
451         if (!(lir->iq&0x80))
452                 /* NULL link incident record */
453                 return -EINVAL;
454         if (!(lir->indesc[0]&0xc0000000))
455                 /* node descriptor not valid */
456                 return -EINVAL;
457         if (!(lir->indesc[0]&0x10000000))
458                 /* don't handle device-type nodes - FIXME */
459                 return -EINVAL;
460         /* Byte 3 contains the chpid. Could also be CTCA, but we don't care */
461
462         return (u16) (lir->indesc[0]&0x000000ff);
463 }
464
465 int
466 chsc_process_crw(void)
467 {
468         int chpid, ret;
469         struct {
470                 struct chsc_header request;
471                 u32 reserved1;
472                 u32 reserved2;
473                 u32 reserved3;
474                 struct chsc_header response;
475                 u32 reserved4;
476                 u8  flags;
477                 u8  vf;         /* validity flags */
478                 u8  rs;         /* reporting source */
479                 u8  cc;         /* content code */
480                 u16 fla;        /* full link address */
481                 u16 rsid;       /* reporting source id */
482                 u32 reserved5;
483                 u32 reserved6;
484                 u32 ccdf[96];   /* content-code dependent field */
485                 /* ccdf has to be big enough for a link-incident record */
486         } *sei_area;
487
488         if (!sei_page)
489                 return 0;
490         /*
491          * build the chsc request block for store event information
492          * and do the call
493          * This function is only called by the machine check handler thread,
494          * so we don't need locking for the sei_page.
495          */
496         sei_area = sei_page;
497
498         CIO_TRACE_EVENT( 2, "prcss");
499         ret = 0;
500         do {
501                 int ccode, status;
502                 memset(sei_area, 0, sizeof(*sei_area));
503
504                 sei_area->request = (struct chsc_header) {
505                         .length = 0x0010,
506                         .code   = 0x000e,
507                 };
508
509                 ccode = chsc(sei_area);
510                 if (ccode > 0)
511                         return 0;
512
513                 switch (sei_area->response.code) {
514                         /* for debug purposes, check for problems */
515                 case 0x0001:
516                         CIO_CRW_EVENT(4, "chsc_process_crw: event information "
517                                         "successfully stored\n");
518                         break; /* everything ok */
519                 case 0x0002:
520                         CIO_CRW_EVENT(2,
521                                       "chsc_process_crw: invalid command!\n");
522                         return 0;
523                 case 0x0003:
524                         CIO_CRW_EVENT(2, "chsc_process_crw: error in chsc "
525                                       "request block!\n");
526                         return 0;
527                 case 0x0005:
528                         CIO_CRW_EVENT(2, "chsc_process_crw: no event "
529                                       "information stored\n");
530                         return 0;
531                 default:
532                         CIO_CRW_EVENT(2, "chsc_process_crw: chsc response %d\n",
533                                       sei_area->response.code);
534                         return 0;
535                 }
536
537                 /* Check if we might have lost some information. */
538                 if (sei_area->flags & 0x40)
539                         CIO_CRW_EVENT(2, "chsc_process_crw: Event information "
540                                        "has been lost due to overflow!\n");
541
542                 if (sei_area->rs != 4) {
543                         CIO_CRW_EVENT(2, "chsc_process_crw: reporting source "
544                                       "(%04X) isn't a chpid!\n",
545                                       sei_area->rsid);
546                         continue;
547                 }
548
549                 /* which kind of information was stored? */
550                 switch (sei_area->cc) {
551                 case 1: /* link incident*/
552                         CIO_CRW_EVENT(4, "chsc_process_crw: "
553                                       "channel subsystem reports link incident,"
554                                       " reporting source is chpid %x\n",
555                                       sei_area->rsid);
556                         chpid = __get_chpid_from_lir(sei_area->ccdf);
557                         if (chpid < 0)
558                                 CIO_CRW_EVENT(4, "%s: Invalid LIR, skipping\n",
559                                               __FUNCTION__);
560                         else
561                                 s390_set_chpid_offline(chpid);
562                         break;
563                         
564                 case 2: /* i/o resource accessibiliy */
565                         CIO_CRW_EVENT(4, "chsc_process_crw: "
566                                       "channel subsystem reports some I/O "
567                                       "devices may have become accessible\n");
568                         pr_debug("Data received after sei: \n");
569                         pr_debug("Validity flags: %x\n", sei_area->vf);
570                         
571                         /* allocate a new channel path structure, if needed */
572                         status = get_chp_status(sei_area->rsid);
573                         if (status < 0)
574                                 new_channel_path(sei_area->rsid);
575                         else if (!status)
576                                 return 0;
577                         if ((sei_area->vf & 0x80) == 0) {
578                                 pr_debug("chpid: %x\n", sei_area->rsid);
579                                 ret = s390_process_res_acc(sei_area->rsid,
580                                                            0, 0);
581                         } else if ((sei_area->vf & 0xc0) == 0x80) {
582                                 pr_debug("chpid: %x link addr: %x\n",
583                                          sei_area->rsid, sei_area->fla);
584                                 ret = s390_process_res_acc(sei_area->rsid,
585                                                            sei_area->fla,
586                                                            0xff00);
587                         } else if ((sei_area->vf & 0xc0) == 0xc0) {
588                                 pr_debug("chpid: %x full link addr: %x\n",
589                                          sei_area->rsid, sei_area->fla);
590                                 ret = s390_process_res_acc(sei_area->rsid,
591                                                            sei_area->fla,
592                                                            0xffff);
593                         }
594                         pr_debug("\n");
595                         
596                         break;
597                         
598                 default: /* other stuff */
599                         CIO_CRW_EVENT(4, "chsc_process_crw: event %d\n",
600                                       sei_area->cc);
601                         break;
602                 }
603         } while (sei_area->flags & 0x80);
604         return ret;
605 }
606
607 static int
608 chp_add(int chpid)
609 {
610         struct subchannel *sch;
611         int irq, ret, rc;
612         char dbf_txt[15];
613
614         if (!get_chp_status(chpid))
615                 return 0; /* no need to do the rest */
616         
617         sprintf(dbf_txt, "cadd%x", chpid);
618         CIO_TRACE_EVENT(2, dbf_txt);
619
620         rc = 0;
621         for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
622                 int i;
623
624                 sch = get_subchannel_by_schid(irq);
625                 if (!sch) {
626                         struct schib schib;
627
628                         if (stsch(irq, &schib)) {
629                                 /* We're through */
630                                 if (need_rescan)
631                                         rc = -EAGAIN;
632                                 break;
633                         }
634                         if (need_rescan) {
635                                 rc = -EAGAIN;
636                                 continue;
637                         }
638                         /* Put it on the slow path. */
639                         ret = css_enqueue_subchannel_slow(irq);
640                         if (ret) {
641                                 css_clear_subchannel_slow_list();
642                                 need_rescan = 1;
643                         }
644                         rc = -EAGAIN;
645                         continue;
646                 }
647         
648                 spin_lock(&sch->lock);
649                 for (i=0; i<8; i++)
650                         if (sch->schib.pmcw.chpid[i] == chpid) {
651                                 if (stsch(sch->irq, &sch->schib) != 0) {
652                                         /* Endgame. */
653                                         spin_unlock(&sch->lock);
654                                         return rc;
655                                 }
656                                 break;
657                         }
658                 if (i==8) {
659                         spin_unlock(&sch->lock);
660                         return rc;
661                 }
662                 sch->lpm = ((sch->schib.pmcw.pim &
663                              sch->schib.pmcw.pam &
664                              sch->schib.pmcw.pom)
665                             | 0x80 >> i) & sch->opm;
666
667                 if (sch->driver && sch->driver->verify)
668                         sch->driver->verify(&sch->dev);
669
670                 spin_unlock(&sch->lock);
671                 put_device(&sch->dev);
672         }
673         return rc;
674 }
675
676 /* 
677  * Handling of crw machine checks with channel path source.
678  */
679 int
680 chp_process_crw(int chpid, int on)
681 {
682         if (on == 0) {
683                 /* Path has gone. We use the link incident routine.*/
684                 s390_set_chpid_offline(chpid);
685                 return 0; /* De-register is async anyway. */
686         }
687         /*
688          * Path has come. Allocate a new channel path structure,
689          * if needed.
690          */
691         if (get_chp_status(chpid) < 0)
692                 new_channel_path(chpid);
693         /* Avoid the extra overhead in process_rec_acc. */
694         return chp_add(chpid);
695 }
696
697 static inline int
698 __check_for_io_and_kill(struct subchannel *sch, int index)
699 {
700         int cc;
701
702         if (!device_is_online(sch))
703                 /* cio could be doing I/O. */
704                 return 0;
705         cc = stsch(sch->irq, &sch->schib);
706         if (cc)
707                 return 0;
708         if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index)) {
709                 device_set_waiting(sch);
710                 return 1;
711         }
712         return 0;
713 }
714
715 static inline void
716 __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
717 {
718         int chp, old_lpm;
719         unsigned long flags;
720
721         if (!sch->ssd_info.valid)
722                 return;
723         
724         spin_lock_irqsave(&sch->lock, flags);
725         old_lpm = sch->lpm;
726         for (chp = 0; chp < 8; chp++) {
727                 if (sch->ssd_info.chpid[chp] != chpid)
728                         continue;
729
730                 if (on) {
731                         sch->opm |= (0x80 >> chp);
732                         sch->lpm |= (0x80 >> chp);
733                         if (!old_lpm)
734                                 device_trigger_reprobe(sch);
735                         else if (sch->driver && sch->driver->verify)
736                                 sch->driver->verify(&sch->dev);
737                 } else {
738                         sch->opm &= ~(0x80 >> chp);
739                         sch->lpm &= ~(0x80 >> chp);
740                         /*
741                          * Give running I/O a grace period in which it
742                          * can successfully terminate, even using the
743                          * just varied off path. Then kill it.
744                          */
745                         if (!__check_for_io_and_kill(sch, chp) && !sch->lpm) {
746                                 if (css_enqueue_subchannel_slow(sch->irq)) {
747                                         css_clear_subchannel_slow_list();
748                                         need_rescan = 1;
749                                 }
750                         } else if (sch->driver && sch->driver->verify)
751                                 sch->driver->verify(&sch->dev);
752                 }
753                 break;
754         }
755         spin_unlock_irqrestore(&sch->lock, flags);
756 }
757
758 static int
759 s390_subchannel_vary_chpid_off(struct device *dev, void *data)
760 {
761         struct subchannel *sch;
762         __u8 *chpid;
763
764         sch = to_subchannel(dev);
765         chpid = data;
766
767         __s390_subchannel_vary_chpid(sch, *chpid, 0);
768         return 0;
769 }
770
771 static int
772 s390_subchannel_vary_chpid_on(struct device *dev, void *data)
773 {
774         struct subchannel *sch;
775         __u8 *chpid;
776
777         sch = to_subchannel(dev);
778         chpid = data;
779
780         __s390_subchannel_vary_chpid(sch, *chpid, 1);
781         return 0;
782 }
783
784 /*
785  * Function: s390_vary_chpid
786  * Varies the specified chpid online or offline
787  */
788 static int
789 s390_vary_chpid( __u8 chpid, int on)
790 {
791         char dbf_text[15];
792         int status, irq, ret;
793         struct subchannel *sch;
794
795         sprintf(dbf_text, on?"varyon%x":"varyoff%x", chpid);
796         CIO_TRACE_EVENT( 2, dbf_text);
797
798         status = get_chp_status(chpid);
799         if (status < 0) {
800                 printk(KERN_ERR "Can't vary unknown chpid %02X\n", chpid);
801                 return -EINVAL;
802         }
803
804         if (!on && !status) {
805                 printk(KERN_ERR "chpid %x is already offline\n", chpid);
806                 return -EINVAL;
807         }
808
809         set_chp_logically_online(chpid, on);
810
811         /*
812          * Redo PathVerification on the devices the chpid connects to
813          */
814
815         bus_for_each_dev(&css_bus_type, NULL, &chpid, on ?
816                          s390_subchannel_vary_chpid_on :
817                          s390_subchannel_vary_chpid_off);
818         if (!on)
819                 goto out;
820         /* Scan for new devices on varied on path. */
821         for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
822                 struct schib schib;
823
824                 if (need_rescan)
825                         break;
826                 sch = get_subchannel_by_schid(irq);
827                 if (sch) {
828                         put_device(&sch->dev);
829                         continue;
830                 }
831                 if (stsch(irq, &schib))
832                         /* We're through */
833                         break;
834                 /* Put it on the slow path. */
835                 ret = css_enqueue_subchannel_slow(irq);
836                 if (ret) {
837                         css_clear_subchannel_slow_list();
838                         need_rescan = 1;
839                 }
840         }
841 out:
842         if (need_rescan || css_slow_subchannels_exist())
843                 queue_work(slow_path_wq, &slow_path_work);
844         return 0;
845 }
846
847 /*
848  * Files for the channel path entries.
849  */
850 static ssize_t
851 chp_status_show(struct device *dev, struct device_attribute *attr, char *buf)
852 {
853         struct channel_path *chp = container_of(dev, struct channel_path, dev);
854
855         if (!chp)
856                 return 0;
857         return (get_chp_status(chp->id) ? sprintf(buf, "online\n") :
858                 sprintf(buf, "offline\n"));
859 }
860
861 static ssize_t
862 chp_status_write(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
863 {
864         struct channel_path *cp = container_of(dev, struct channel_path, dev);
865         char cmd[10];
866         int num_args;
867         int error;
868
869         num_args = sscanf(buf, "%5s", cmd);
870         if (!num_args)
871                 return count;
872
873         if (!strnicmp(cmd, "on", 2))
874                 error = s390_vary_chpid(cp->id, 1);
875         else if (!strnicmp(cmd, "off", 3))
876                 error = s390_vary_chpid(cp->id, 0);
877         else
878                 error = -EINVAL;
879
880         return error < 0 ? error : count;
881
882 }
883
884 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
885
886 static ssize_t
887 chp_type_show(struct device *dev, struct device_attribute *attr, char *buf)
888 {
889         struct channel_path *chp = container_of(dev, struct channel_path, dev);
890
891         if (!chp)
892                 return 0;
893         return sprintf(buf, "%x\n", chp->desc.desc);
894 }
895
896 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
897
898 static struct attribute * chp_attrs[] = {
899         &dev_attr_status.attr,
900         &dev_attr_type.attr,
901         NULL,
902 };
903
904 static struct attribute_group chp_attr_group = {
905         .attrs = chp_attrs,
906 };
907
908 static void
909 chp_release(struct device *dev)
910 {
911         struct channel_path *cp;
912         
913         cp = container_of(dev, struct channel_path, dev);
914         kfree(cp);
915 }
916
917 static int
918 chsc_determine_channel_path_description(int chpid,
919                                         struct channel_path_desc *desc)
920 {
921         int ccode, ret;
922
923         struct {
924                 struct chsc_header request;
925                 u32 : 24;
926                 u32 first_chpid : 8;
927                 u32 : 24;
928                 u32 last_chpid : 8;
929                 u32 zeroes1;
930                 struct chsc_header response;
931                 u32 zeroes2;
932                 struct channel_path_desc desc;
933         } *scpd_area;
934
935         scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
936         if (!scpd_area)
937                 return -ENOMEM;
938
939         scpd_area->request = (struct chsc_header) {
940                 .length = 0x0010,
941                 .code   = 0x0002,
942         };
943
944         scpd_area->first_chpid = chpid;
945         scpd_area->last_chpid = chpid;
946
947         ccode = chsc(scpd_area);
948         if (ccode > 0) {
949                 ret = (ccode == 3) ? -ENODEV : -EBUSY;
950                 goto out;
951         }
952
953         switch (scpd_area->response.code) {
954         case 0x0001: /* Success. */
955                 memcpy(desc, &scpd_area->desc,
956                        sizeof(struct channel_path_desc));
957                 ret = 0;
958                 break;
959         case 0x0003: /* Invalid block. */
960         case 0x0007: /* Invalid format. */
961         case 0x0008: /* Other invalid block. */
962                 CIO_CRW_EVENT(2, "Error in chsc request block!\n");
963                 ret = -EINVAL;
964                 break;
965         case 0x0004: /* Command not provided in model. */
966                 CIO_CRW_EVENT(2, "Model does not provide scpd\n");
967                 ret = -EOPNOTSUPP;
968                 break;
969         default:
970                 CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
971                               scpd_area->response.code);
972                 ret = -EIO;
973         }
974 out:
975         free_page((unsigned long)scpd_area);
976         return ret;
977 }
978
979 /*
980  * Entries for chpids on the system bus.
981  * This replaces /proc/chpids.
982  */
983 static int
984 new_channel_path(int chpid)
985 {
986         struct channel_path *chp;
987         int ret;
988
989         chp = kmalloc(sizeof(struct channel_path), GFP_KERNEL);
990         if (!chp)
991                 return -ENOMEM;
992         memset(chp, 0, sizeof(struct channel_path));
993
994         /* fill in status, etc. */
995         chp->id = chpid;
996         chp->state = 1;
997         chp->dev = (struct device) {
998                 .parent  = &css_bus_device,
999                 .release = chp_release,
1000         };
1001         snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp0.%x", chpid);
1002
1003         /* Obtain channel path description and fill it in. */
1004         ret = chsc_determine_channel_path_description(chpid, &chp->desc);
1005         if (ret)
1006                 goto out_free;
1007
1008         /* make it known to the system */
1009         ret = device_register(&chp->dev);
1010         if (ret) {
1011                 printk(KERN_WARNING "%s: could not register %02x\n",
1012                        __func__, chpid);
1013                 goto out_free;
1014         }
1015         ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
1016         if (ret) {
1017                 device_unregister(&chp->dev);
1018                 goto out_free;
1019         } else
1020                 chps[chpid] = chp;
1021         return ret;
1022 out_free:
1023         kfree(chp);
1024         return ret;
1025 }
1026
1027 void *
1028 chsc_get_chp_desc(struct subchannel *sch, int chp_no)
1029 {
1030         struct channel_path *chp;
1031         struct channel_path_desc *desc;
1032
1033         chp = chps[sch->schib.pmcw.chpid[chp_no]];
1034         if (!chp)
1035                 return NULL;
1036         desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
1037         if (!desc)
1038                 return NULL;
1039         memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
1040         return desc;
1041 }
1042
1043
1044 static int __init
1045 chsc_alloc_sei_area(void)
1046 {
1047         sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1048         if (!sei_page)
1049                 printk(KERN_WARNING"Can't allocate page for processing of " \
1050                        "chsc machine checks!\n");
1051         return (sei_page ? 0 : -ENOMEM);
1052 }
1053
1054 subsys_initcall(chsc_alloc_sei_area);
1055
1056 struct css_general_char css_general_characteristics;
1057 struct css_chsc_char css_chsc_characteristics;
1058
1059 int __init
1060 chsc_determine_css_characteristics(void)
1061 {
1062         int result;
1063         struct {
1064                 struct chsc_header request;
1065                 u32 reserved1;
1066                 u32 reserved2;
1067                 u32 reserved3;
1068                 struct chsc_header response;
1069                 u32 reserved4;
1070                 u32 general_char[510];
1071                 u32 chsc_char[518];
1072         } *scsc_area;
1073
1074         scsc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1075         if (!scsc_area) {
1076                 printk(KERN_WARNING"cio: Was not able to determine available" \
1077                        "CHSCs due to no memory.\n");
1078                 return -ENOMEM;
1079         }
1080
1081         scsc_area->request = (struct chsc_header) {
1082                 .length = 0x0010,
1083                 .code   = 0x0010,
1084         };
1085
1086         result = chsc(scsc_area);
1087         if (result) {
1088                 printk(KERN_WARNING"cio: Was not able to determine " \
1089                        "available CHSCs, cc=%i.\n", result);
1090                 result = -EIO;
1091                 goto exit;
1092         }
1093
1094         if (scsc_area->response.code != 1) {
1095                 printk(KERN_WARNING"cio: Was not able to determine " \
1096                        "available CHSCs.\n");
1097                 result = -EIO;
1098                 goto exit;
1099         }
1100         memcpy(&css_general_characteristics, scsc_area->general_char,
1101                sizeof(css_general_characteristics));
1102         memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1103                sizeof(css_chsc_characteristics));
1104 exit:
1105         free_page ((unsigned long) scsc_area);
1106         return result;
1107 }
1108
1109 EXPORT_SYMBOL_GPL(css_general_characteristics);
1110 EXPORT_SYMBOL_GPL(css_chsc_characteristics);