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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Author(s)......: Carsten Otte <cotte@de.ibm.com>
4 * Rob M van der Heij <rvdheij@nl.ibm.com>
5 * Steven Shultz <shultzss@us.ibm.com>
6 * Bugreports.to..: <Linux390@de.ibm.com>
7 * Copyright IBM Corp. 2002, 2004
8 */
9
10#define KMSG_COMPONENT "extmem"
11#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12
13#include <linux/kernel.h>
14#include <linux/string.h>
15#include <linux/spinlock.h>
16#include <linux/list.h>
17#include <linux/slab.h>
18#include <linux/export.h>
19#include <linux/memblock.h>
20#include <linux/ctype.h>
21#include <linux/ioport.h>
22#include <linux/refcount.h>
23#include <linux/pgtable.h>
24#include <asm/diag.h>
25#include <asm/page.h>
26#include <asm/ebcdic.h>
27#include <asm/errno.h>
28#include <asm/extmem.h>
29#include <asm/cpcmd.h>
30#include <asm/setup.h>
31#include <asm/asm.h>
32
33#define DCSS_PURGESEG 0x08
34#define DCSS_LOADSHRX 0x20
35#define DCSS_LOADNSRX 0x24
36#define DCSS_FINDSEGX 0x2c
37#define DCSS_SEGEXTX 0x38
38#define DCSS_FINDSEGA 0x0c
39
40struct qrange {
41 unsigned long start; /* last byte type */
42 unsigned long end; /* last byte reserved */
43};
44
45struct qout64 {
46 unsigned long segstart;
47 unsigned long segend;
48 int segcnt;
49 int segrcnt;
50 struct qrange range[6];
51};
52
53struct qin64 {
54 char qopcode;
55 char rsrv1[3];
56 char qrcode;
57 char rsrv2[3];
58 char qname[8];
59 unsigned int qoutptr;
60 short int qoutlen;
61};
62
63struct dcss_segment {
64 struct list_head list;
65 char dcss_name[8];
66 char res_name[16];
67 unsigned long start_addr;
68 unsigned long end;
69 refcount_t ref_count;
70 int do_nonshared;
71 unsigned int vm_segtype;
72 struct qrange range[6];
73 int segcnt;
74 struct resource *res;
75};
76
77static DEFINE_MUTEX(dcss_lock);
78static LIST_HEAD(dcss_list);
79static char *segtype_string[] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC",
80 "EW/EN-MIXED" };
81static int loadshr_scode = DCSS_LOADSHRX;
82static int loadnsr_scode = DCSS_LOADNSRX;
83static int purgeseg_scode = DCSS_PURGESEG;
84static int segext_scode = DCSS_SEGEXTX;
85
86/*
87 * Create the 8 bytes, ebcdic VM segment name from
88 * an ascii name.
89 */
90static void
91dcss_mkname(char *name, char *dcss_name)
92{
93 int i;
94
95 for (i = 0; i < 8; i++) {
96 if (name[i] == '\0')
97 break;
98 dcss_name[i] = toupper(name[i]);
99 }
100 for (; i < 8; i++)
101 dcss_name[i] = ' ';
102 ASCEBC(dcss_name, 8);
103}
104
105
106/*
107 * search all segments in dcss_list, and return the one
108 * namend *name. If not found, return NULL.
109 */
110static struct dcss_segment *
111segment_by_name (char *name)
112{
113 char dcss_name[9];
114 struct list_head *l;
115 struct dcss_segment *tmp, *retval = NULL;
116
117 BUG_ON(!mutex_is_locked(&dcss_lock));
118 dcss_mkname (name, dcss_name);
119 list_for_each (l, &dcss_list) {
120 tmp = list_entry (l, struct dcss_segment, list);
121 if (memcmp(tmp->dcss_name, dcss_name, 8) == 0) {
122 retval = tmp;
123 break;
124 }
125 }
126 return retval;
127}
128
129
130/*
131 * Perform a function on a dcss segment.
132 */
133static inline int
134dcss_diag(int *func, void *parameter,
135 unsigned long *ret1, unsigned long *ret2)
136{
137 unsigned long rx, ry;
138 int cc;
139
140 rx = virt_to_phys(parameter);
141 ry = (unsigned long) *func;
142
143 diag_stat_inc(DIAG_STAT_X064);
144 asm volatile(
145 " diag %[rx],%[ry],0x64\n"
146 CC_IPM(cc)
147 : CC_OUT(cc, cc), [rx] "+d" (rx), [ry] "+d" (ry)
148 :
149 : CC_CLOBBER);
150 *ret1 = rx;
151 *ret2 = ry;
152 return CC_TRANSFORM(cc);
153}
154
155static inline int
156dcss_diag_translate_rc (int vm_rc) {
157 if (vm_rc == 44)
158 return -ENOENT;
159 return -EIO;
160}
161
162
163/* do a diag to get info about a segment.
164 * fills start_address, end and vm_segtype fields
165 */
166static int
167query_segment_type (struct dcss_segment *seg)
168{
169 unsigned long dummy, vmrc;
170 int diag_cc, rc, i;
171 struct qout64 *qout;
172 struct qin64 *qin;
173
174 qin = kmalloc(sizeof(*qin), GFP_KERNEL | GFP_DMA);
175 qout = kmalloc(sizeof(*qout), GFP_KERNEL | GFP_DMA);
176 if ((qin == NULL) || (qout == NULL)) {
177 rc = -ENOMEM;
178 goto out_free;
179 }
180
181 /* initialize diag input parameters */
182 qin->qopcode = DCSS_FINDSEGA;
183 qin->qoutptr = virt_to_phys(qout);
184 qin->qoutlen = sizeof(struct qout64);
185 memcpy (qin->qname, seg->dcss_name, 8);
186
187 diag_cc = dcss_diag(&segext_scode, qin, &dummy, &vmrc);
188
189 if (diag_cc < 0) {
190 rc = diag_cc;
191 goto out_free;
192 }
193 if (diag_cc > 1) {
194 pr_warn("Querying a DCSS type failed with rc=%ld\n", vmrc);
195 rc = dcss_diag_translate_rc (vmrc);
196 goto out_free;
197 }
198
199 if (qout->segcnt > 6) {
200 rc = -EOPNOTSUPP;
201 goto out_free;
202 }
203
204 if (qout->segcnt == 1) {
205 seg->vm_segtype = qout->range[0].start & 0xff;
206 } else {
207 /* multi-part segment. only one type supported here:
208 - all parts are contiguous
209 - all parts are either EW or EN type
210 - maximum 6 parts allowed */
211 unsigned long start = qout->segstart >> PAGE_SHIFT;
212 for (i=0; i<qout->segcnt; i++) {
213 if (((qout->range[i].start & 0xff) != SEG_TYPE_EW) &&
214 ((qout->range[i].start & 0xff) != SEG_TYPE_EN)) {
215 rc = -EOPNOTSUPP;
216 goto out_free;
217 }
218 if (start != qout->range[i].start >> PAGE_SHIFT) {
219 rc = -EOPNOTSUPP;
220 goto out_free;
221 }
222 start = (qout->range[i].end >> PAGE_SHIFT) + 1;
223 }
224 seg->vm_segtype = SEG_TYPE_EWEN;
225 }
226
227 /* analyze diag output and update seg */
228 seg->start_addr = qout->segstart;
229 seg->end = qout->segend;
230
231 memcpy (seg->range, qout->range, 6*sizeof(struct qrange));
232 seg->segcnt = qout->segcnt;
233
234 rc = 0;
235
236 out_free:
237 kfree(qin);
238 kfree(qout);
239 return rc;
240}
241
242/*
243 * get info about a segment
244 * possible return values:
245 * -ENOSYS : we are not running on VM
246 * -EIO : could not perform query diagnose
247 * -ENOENT : no such segment
248 * -EOPNOTSUPP: multi-part segment cannot be used with linux
249 * -ENOMEM : out of memory
250 * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
251 */
252int
253segment_type (char* name)
254{
255 int rc;
256 struct dcss_segment seg;
257
258 if (!MACHINE_IS_VM)
259 return -ENOSYS;
260
261 dcss_mkname(name, seg.dcss_name);
262 rc = query_segment_type (&seg);
263 if (rc < 0)
264 return rc;
265 return seg.vm_segtype;
266}
267
268/*
269 * check if segment collides with other segments that are currently loaded
270 * returns 1 if this is the case, 0 if no collision was found
271 */
272static int
273segment_overlaps_others (struct dcss_segment *seg)
274{
275 struct list_head *l;
276 struct dcss_segment *tmp;
277
278 BUG_ON(!mutex_is_locked(&dcss_lock));
279 list_for_each(l, &dcss_list) {
280 tmp = list_entry(l, struct dcss_segment, list);
281 if ((tmp->start_addr >> 20) > (seg->end >> 20))
282 continue;
283 if ((tmp->end >> 20) < (seg->start_addr >> 20))
284 continue;
285 if (seg == tmp)
286 continue;
287 return 1;
288 }
289 return 0;
290}
291
292/*
293 * real segment loading function, called from segment_load
294 * Must return either an error code < 0, or the segment type code >= 0
295 */
296static int
297__segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
298{
299 unsigned long start_addr, end_addr, dummy;
300 struct dcss_segment *seg;
301 int rc, diag_cc, segtype;
302
303 start_addr = end_addr = 0;
304 segtype = -1;
305 seg = kmalloc(sizeof(*seg), GFP_KERNEL | GFP_DMA);
306 if (seg == NULL) {
307 rc = -ENOMEM;
308 goto out;
309 }
310 dcss_mkname (name, seg->dcss_name);
311 rc = query_segment_type (seg);
312 if (rc < 0)
313 goto out_free;
314
315 if (segment_overlaps_others(seg)) {
316 rc = -EBUSY;
317 goto out_free;
318 }
319
320 seg->res = kzalloc(sizeof(struct resource), GFP_KERNEL);
321 if (seg->res == NULL) {
322 rc = -ENOMEM;
323 goto out_free;
324 }
325 seg->res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
326 seg->res->start = seg->start_addr;
327 seg->res->end = seg->end;
328 memcpy(&seg->res_name, seg->dcss_name, 8);
329 EBCASC(seg->res_name, 8);
330 seg->res_name[8] = '\0';
331 strlcat(seg->res_name, " (DCSS)", sizeof(seg->res_name));
332 seg->res->name = seg->res_name;
333 segtype = seg->vm_segtype;
334 if (segtype == SEG_TYPE_SC ||
335 ((segtype == SEG_TYPE_SR || segtype == SEG_TYPE_ER) && !do_nonshared))
336 seg->res->flags |= IORESOURCE_READONLY;
337
338 /* Check for overlapping resources before adding the mapping. */
339 if (request_resource(&iomem_resource, seg->res)) {
340 rc = -EBUSY;
341 goto out_free_resource;
342 }
343
344 rc = vmem_add_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
345 if (rc)
346 goto out_resource;
347
348 if (do_nonshared)
349 diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
350 &start_addr, &end_addr);
351 else
352 diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
353 &start_addr, &end_addr);
354 if (diag_cc < 0) {
355 dcss_diag(&purgeseg_scode, seg->dcss_name,
356 &dummy, &dummy);
357 rc = diag_cc;
358 goto out_mapping;
359 }
360 if (diag_cc > 1) {
361 pr_warn("Loading DCSS %s failed with rc=%ld\n", name, end_addr);
362 rc = dcss_diag_translate_rc(end_addr);
363 dcss_diag(&purgeseg_scode, seg->dcss_name,
364 &dummy, &dummy);
365 goto out_mapping;
366 }
367 seg->start_addr = start_addr;
368 seg->end = end_addr;
369 seg->do_nonshared = do_nonshared;
370 refcount_set(&seg->ref_count, 1);
371 list_add(&seg->list, &dcss_list);
372 *addr = seg->start_addr;
373 *end = seg->end;
374 if (do_nonshared)
375 pr_info("DCSS %s of range %px to %px and type %s loaded as "
376 "exclusive-writable\n", name, (void*) seg->start_addr,
377 (void*) seg->end, segtype_string[seg->vm_segtype]);
378 else {
379 pr_info("DCSS %s of range %px to %px and type %s loaded in "
380 "shared access mode\n", name, (void*) seg->start_addr,
381 (void*) seg->end, segtype_string[seg->vm_segtype]);
382 }
383 goto out;
384 out_mapping:
385 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
386 out_resource:
387 release_resource(seg->res);
388 out_free_resource:
389 kfree(seg->res);
390 out_free:
391 kfree(seg);
392 out:
393 return rc < 0 ? rc : segtype;
394}
395
396/*
397 * this function loads a DCSS segment
398 * name : name of the DCSS
399 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
400 * 1 indicates that the dcss should be exclusive for this linux image
401 * addr : will be filled with start address of the segment
402 * end : will be filled with end address of the segment
403 * return values:
404 * -ENOSYS : we are not running on VM
405 * -EIO : could not perform query or load diagnose
406 * -ENOENT : no such segment
407 * -EOPNOTSUPP: multi-part segment cannot be used with linux
408 * -EBUSY : segment cannot be used (overlaps with dcss or storage)
409 * -ERANGE : segment cannot be used (exceeds kernel mapping range)
410 * -EPERM : segment is currently loaded with incompatible permissions
411 * -ENOMEM : out of memory
412 * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
413 */
414int
415segment_load (char *name, int do_nonshared, unsigned long *addr,
416 unsigned long *end)
417{
418 struct dcss_segment *seg;
419 int rc;
420
421 if (!MACHINE_IS_VM)
422 return -ENOSYS;
423
424 mutex_lock(&dcss_lock);
425 seg = segment_by_name (name);
426 if (seg == NULL)
427 rc = __segment_load (name, do_nonshared, addr, end);
428 else {
429 if (do_nonshared == seg->do_nonshared) {
430 refcount_inc(&seg->ref_count);
431 *addr = seg->start_addr;
432 *end = seg->end;
433 rc = seg->vm_segtype;
434 } else {
435 *addr = *end = 0;
436 rc = -EPERM;
437 }
438 }
439 mutex_unlock(&dcss_lock);
440 return rc;
441}
442
443/*
444 * this function modifies the shared state of a DCSS segment. note that
445 * name : name of the DCSS
446 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
447 * 1 indicates that the dcss should be exclusive for this linux image
448 * return values:
449 * -EIO : could not perform load diagnose (segment gone!)
450 * -ENOENT : no such segment (segment gone!)
451 * -EAGAIN : segment is in use by other exploiters, try later
452 * -EINVAL : no segment with the given name is currently loaded - name invalid
453 * -EBUSY : segment can temporarily not be used (overlaps with dcss)
454 * 0 : operation succeeded
455 */
456int
457segment_modify_shared (char *name, int do_nonshared)
458{
459 struct dcss_segment *seg;
460 unsigned long start_addr, end_addr, dummy;
461 int rc, diag_cc;
462
463 start_addr = end_addr = 0;
464 mutex_lock(&dcss_lock);
465 seg = segment_by_name (name);
466 if (seg == NULL) {
467 rc = -EINVAL;
468 goto out_unlock;
469 }
470 if (do_nonshared == seg->do_nonshared) {
471 pr_info("DCSS %s is already in the requested access "
472 "mode\n", name);
473 rc = 0;
474 goto out_unlock;
475 }
476 if (refcount_read(&seg->ref_count) != 1) {
477 pr_warn("DCSS %s is in use and cannot be reloaded\n", name);
478 rc = -EAGAIN;
479 goto out_unlock;
480 }
481 release_resource(seg->res);
482 if (do_nonshared)
483 seg->res->flags &= ~IORESOURCE_READONLY;
484 else
485 if (seg->vm_segtype == SEG_TYPE_SR ||
486 seg->vm_segtype == SEG_TYPE_ER)
487 seg->res->flags |= IORESOURCE_READONLY;
488
489 if (request_resource(&iomem_resource, seg->res)) {
490 pr_warn("DCSS %s overlaps with used memory resources and cannot be reloaded\n",
491 name);
492 rc = -EBUSY;
493 kfree(seg->res);
494 goto out_del_mem;
495 }
496
497 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
498 if (do_nonshared)
499 diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
500 &start_addr, &end_addr);
501 else
502 diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
503 &start_addr, &end_addr);
504 if (diag_cc < 0) {
505 rc = diag_cc;
506 goto out_del_res;
507 }
508 if (diag_cc > 1) {
509 pr_warn("Reloading DCSS %s failed with rc=%ld\n",
510 name, end_addr);
511 rc = dcss_diag_translate_rc(end_addr);
512 goto out_del_res;
513 }
514 seg->start_addr = start_addr;
515 seg->end = end_addr;
516 seg->do_nonshared = do_nonshared;
517 rc = 0;
518 goto out_unlock;
519 out_del_res:
520 release_resource(seg->res);
521 kfree(seg->res);
522 out_del_mem:
523 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
524 list_del(&seg->list);
525 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
526 kfree(seg);
527 out_unlock:
528 mutex_unlock(&dcss_lock);
529 return rc;
530}
531
532/*
533 * Decrease the use count of a DCSS segment and remove
534 * it from the address space if nobody is using it
535 * any longer.
536 */
537void
538segment_unload(char *name)
539{
540 unsigned long dummy;
541 struct dcss_segment *seg;
542
543 if (!MACHINE_IS_VM)
544 return;
545
546 mutex_lock(&dcss_lock);
547 seg = segment_by_name (name);
548 if (seg == NULL) {
549 pr_err("Unloading unknown DCSS %s failed\n", name);
550 goto out_unlock;
551 }
552 if (!refcount_dec_and_test(&seg->ref_count))
553 goto out_unlock;
554 release_resource(seg->res);
555 kfree(seg->res);
556 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
557 list_del(&seg->list);
558 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
559 kfree(seg);
560out_unlock:
561 mutex_unlock(&dcss_lock);
562}
563
564/*
565 * save segment content permanently
566 */
567void
568segment_save(char *name)
569{
570 struct dcss_segment *seg;
571 char cmd1[160];
572 char cmd2[80];
573 int i, response;
574
575 if (!MACHINE_IS_VM)
576 return;
577
578 mutex_lock(&dcss_lock);
579 seg = segment_by_name (name);
580
581 if (seg == NULL) {
582 pr_err("Saving unknown DCSS %s failed\n", name);
583 goto out;
584 }
585
586 sprintf(cmd1, "DEFSEG %s", name);
587 for (i=0; i<seg->segcnt; i++) {
588 sprintf(cmd1+strlen(cmd1), " %lX-%lX %s",
589 seg->range[i].start >> PAGE_SHIFT,
590 seg->range[i].end >> PAGE_SHIFT,
591 segtype_string[seg->range[i].start & 0xff]);
592 }
593 sprintf(cmd2, "SAVESEG %s", name);
594 response = 0;
595 cpcmd(cmd1, NULL, 0, &response);
596 if (response) {
597 pr_err("Saving a DCSS failed with DEFSEG response code "
598 "%i\n", response);
599 goto out;
600 }
601 cpcmd(cmd2, NULL, 0, &response);
602 if (response) {
603 pr_err("Saving a DCSS failed with SAVESEG response code "
604 "%i\n", response);
605 goto out;
606 }
607out:
608 mutex_unlock(&dcss_lock);
609}
610
611/*
612 * print appropriate error message for segment_load()/segment_type()
613 * return code
614 */
615void segment_warning(int rc, char *seg_name)
616{
617 switch (rc) {
618 case -ENOENT:
619 pr_err("DCSS %s cannot be loaded or queried\n", seg_name);
620 break;
621 case -ENOSYS:
622 pr_err("DCSS %s cannot be loaded or queried without "
623 "z/VM\n", seg_name);
624 break;
625 case -EIO:
626 pr_err("Loading or querying DCSS %s resulted in a "
627 "hardware error\n", seg_name);
628 break;
629 case -EOPNOTSUPP:
630 pr_err("DCSS %s has multiple page ranges and cannot be "
631 "loaded or queried\n", seg_name);
632 break;
633 case -EBUSY:
634 pr_err("%s needs used memory resources and cannot be "
635 "loaded or queried\n", seg_name);
636 break;
637 case -EPERM:
638 pr_err("DCSS %s is already loaded in a different access "
639 "mode\n", seg_name);
640 break;
641 case -ENOMEM:
642 pr_err("There is not enough memory to load or query "
643 "DCSS %s\n", seg_name);
644 break;
645 case -ERANGE: {
646 struct range mhp_range = arch_get_mappable_range();
647
648 pr_err("DCSS %s exceeds the kernel mapping range (%llu) "
649 "and cannot be loaded\n", seg_name, mhp_range.end + 1);
650 break;
651 }
652 default:
653 break;
654 }
655}
656
657EXPORT_SYMBOL(segment_load);
658EXPORT_SYMBOL(segment_unload);
659EXPORT_SYMBOL(segment_save);
660EXPORT_SYMBOL(segment_type);
661EXPORT_SYMBOL(segment_modify_shared);
662EXPORT_SYMBOL(segment_warning);
1/*
2 * File...........: arch/s390/mm/extmem.c
3 * Author(s)......: Carsten Otte <cotte@de.ibm.com>
4 * Rob M van der Heij <rvdheij@nl.ibm.com>
5 * Steven Shultz <shultzss@us.ibm.com>
6 * Bugreports.to..: <Linux390@de.ibm.com>
7 * (C) IBM Corporation 2002-2004
8 */
9
10#define KMSG_COMPONENT "extmem"
11#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12
13#include <linux/kernel.h>
14#include <linux/string.h>
15#include <linux/spinlock.h>
16#include <linux/list.h>
17#include <linux/slab.h>
18#include <linux/module.h>
19#include <linux/bootmem.h>
20#include <linux/ctype.h>
21#include <linux/ioport.h>
22#include <asm/page.h>
23#include <asm/pgtable.h>
24#include <asm/ebcdic.h>
25#include <asm/errno.h>
26#include <asm/extmem.h>
27#include <asm/cpcmd.h>
28#include <asm/setup.h>
29
30#define DCSS_LOADSHR 0x00
31#define DCSS_LOADNSR 0x04
32#define DCSS_PURGESEG 0x08
33#define DCSS_FINDSEG 0x0c
34#define DCSS_LOADNOLY 0x10
35#define DCSS_SEGEXT 0x18
36#define DCSS_LOADSHRX 0x20
37#define DCSS_LOADNSRX 0x24
38#define DCSS_FINDSEGX 0x2c
39#define DCSS_SEGEXTX 0x38
40#define DCSS_FINDSEGA 0x0c
41
42struct qrange {
43 unsigned long start; /* last byte type */
44 unsigned long end; /* last byte reserved */
45};
46
47struct qout64 {
48 unsigned long segstart;
49 unsigned long segend;
50 int segcnt;
51 int segrcnt;
52 struct qrange range[6];
53};
54
55#ifdef CONFIG_64BIT
56struct qrange_old {
57 unsigned int start; /* last byte type */
58 unsigned int end; /* last byte reserved */
59};
60
61/* output area format for the Diag x'64' old subcode x'18' */
62struct qout64_old {
63 int segstart;
64 int segend;
65 int segcnt;
66 int segrcnt;
67 struct qrange_old range[6];
68};
69#endif
70
71struct qin64 {
72 char qopcode;
73 char rsrv1[3];
74 char qrcode;
75 char rsrv2[3];
76 char qname[8];
77 unsigned int qoutptr;
78 short int qoutlen;
79};
80
81struct dcss_segment {
82 struct list_head list;
83 char dcss_name[8];
84 char res_name[15];
85 unsigned long start_addr;
86 unsigned long end;
87 atomic_t ref_count;
88 int do_nonshared;
89 unsigned int vm_segtype;
90 struct qrange range[6];
91 int segcnt;
92 struct resource *res;
93};
94
95static DEFINE_MUTEX(dcss_lock);
96static LIST_HEAD(dcss_list);
97static char *segtype_string[] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC",
98 "EW/EN-MIXED" };
99static int loadshr_scode, loadnsr_scode, findseg_scode;
100static int segext_scode, purgeseg_scode;
101static int scode_set;
102
103/* set correct Diag x'64' subcodes. */
104static int
105dcss_set_subcodes(void)
106{
107#ifdef CONFIG_64BIT
108 char *name = kmalloc(8 * sizeof(char), GFP_KERNEL | GFP_DMA);
109 unsigned long rx, ry;
110 int rc;
111
112 if (name == NULL)
113 return -ENOMEM;
114
115 rx = (unsigned long) name;
116 ry = DCSS_FINDSEGX;
117
118 strcpy(name, "dummy");
119 asm volatile(
120 " diag %0,%1,0x64\n"
121 "0: ipm %2\n"
122 " srl %2,28\n"
123 " j 2f\n"
124 "1: la %2,3\n"
125 "2:\n"
126 EX_TABLE(0b, 1b)
127 : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
128
129 kfree(name);
130 /* Diag x'64' new subcodes are supported, set to new subcodes */
131 if (rc != 3) {
132 loadshr_scode = DCSS_LOADSHRX;
133 loadnsr_scode = DCSS_LOADNSRX;
134 purgeseg_scode = DCSS_PURGESEG;
135 findseg_scode = DCSS_FINDSEGX;
136 segext_scode = DCSS_SEGEXTX;
137 return 0;
138 }
139#endif
140 /* Diag x'64' new subcodes are not supported, set to old subcodes */
141 loadshr_scode = DCSS_LOADNOLY;
142 loadnsr_scode = DCSS_LOADNSR;
143 purgeseg_scode = DCSS_PURGESEG;
144 findseg_scode = DCSS_FINDSEG;
145 segext_scode = DCSS_SEGEXT;
146 return 0;
147}
148
149/*
150 * Create the 8 bytes, ebcdic VM segment name from
151 * an ascii name.
152 */
153static void
154dcss_mkname(char *name, char *dcss_name)
155{
156 int i;
157
158 for (i = 0; i < 8; i++) {
159 if (name[i] == '\0')
160 break;
161 dcss_name[i] = toupper(name[i]);
162 };
163 for (; i < 8; i++)
164 dcss_name[i] = ' ';
165 ASCEBC(dcss_name, 8);
166}
167
168
169/*
170 * search all segments in dcss_list, and return the one
171 * namend *name. If not found, return NULL.
172 */
173static struct dcss_segment *
174segment_by_name (char *name)
175{
176 char dcss_name[9];
177 struct list_head *l;
178 struct dcss_segment *tmp, *retval = NULL;
179
180 BUG_ON(!mutex_is_locked(&dcss_lock));
181 dcss_mkname (name, dcss_name);
182 list_for_each (l, &dcss_list) {
183 tmp = list_entry (l, struct dcss_segment, list);
184 if (memcmp(tmp->dcss_name, dcss_name, 8) == 0) {
185 retval = tmp;
186 break;
187 }
188 }
189 return retval;
190}
191
192
193/*
194 * Perform a function on a dcss segment.
195 */
196static inline int
197dcss_diag(int *func, void *parameter,
198 unsigned long *ret1, unsigned long *ret2)
199{
200 unsigned long rx, ry;
201 int rc;
202
203 if (scode_set == 0) {
204 rc = dcss_set_subcodes();
205 if (rc < 0)
206 return rc;
207 scode_set = 1;
208 }
209 rx = (unsigned long) parameter;
210 ry = (unsigned long) *func;
211
212#ifdef CONFIG_64BIT
213 /* 64-bit Diag x'64' new subcode, keep in 64-bit addressing mode */
214 if (*func > DCSS_SEGEXT)
215 asm volatile(
216 " diag %0,%1,0x64\n"
217 " ipm %2\n"
218 " srl %2,28\n"
219 : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
220 /* 31-bit Diag x'64' old subcode, switch to 31-bit addressing mode */
221 else
222 asm volatile(
223 " sam31\n"
224 " diag %0,%1,0x64\n"
225 " sam64\n"
226 " ipm %2\n"
227 " srl %2,28\n"
228 : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
229#else
230 asm volatile(
231 " diag %0,%1,0x64\n"
232 " ipm %2\n"
233 " srl %2,28\n"
234 : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
235#endif
236 *ret1 = rx;
237 *ret2 = ry;
238 return rc;
239}
240
241static inline int
242dcss_diag_translate_rc (int vm_rc) {
243 if (vm_rc == 44)
244 return -ENOENT;
245 return -EIO;
246}
247
248
249/* do a diag to get info about a segment.
250 * fills start_address, end and vm_segtype fields
251 */
252static int
253query_segment_type (struct dcss_segment *seg)
254{
255 unsigned long dummy, vmrc;
256 int diag_cc, rc, i;
257 struct qout64 *qout;
258 struct qin64 *qin;
259
260 qin = kmalloc(sizeof(*qin), GFP_KERNEL | GFP_DMA);
261 qout = kmalloc(sizeof(*qout), GFP_KERNEL | GFP_DMA);
262 if ((qin == NULL) || (qout == NULL)) {
263 rc = -ENOMEM;
264 goto out_free;
265 }
266
267 /* initialize diag input parameters */
268 qin->qopcode = DCSS_FINDSEGA;
269 qin->qoutptr = (unsigned long) qout;
270 qin->qoutlen = sizeof(struct qout64);
271 memcpy (qin->qname, seg->dcss_name, 8);
272
273 diag_cc = dcss_diag(&segext_scode, qin, &dummy, &vmrc);
274
275 if (diag_cc < 0) {
276 rc = diag_cc;
277 goto out_free;
278 }
279 if (diag_cc > 1) {
280 pr_warning("Querying a DCSS type failed with rc=%ld\n", vmrc);
281 rc = dcss_diag_translate_rc (vmrc);
282 goto out_free;
283 }
284
285#ifdef CONFIG_64BIT
286 /* Only old format of output area of Diagnose x'64' is supported,
287 copy data for the new format. */
288 if (segext_scode == DCSS_SEGEXT) {
289 struct qout64_old *qout_old;
290 qout_old = kzalloc(sizeof(*qout_old), GFP_KERNEL | GFP_DMA);
291 if (qout_old == NULL) {
292 rc = -ENOMEM;
293 goto out_free;
294 }
295 memcpy(qout_old, qout, sizeof(struct qout64_old));
296 qout->segstart = (unsigned long) qout_old->segstart;
297 qout->segend = (unsigned long) qout_old->segend;
298 qout->segcnt = qout_old->segcnt;
299 qout->segrcnt = qout_old->segrcnt;
300
301 if (qout->segcnt > 6)
302 qout->segrcnt = 6;
303 for (i = 0; i < qout->segrcnt; i++) {
304 qout->range[i].start =
305 (unsigned long) qout_old->range[i].start;
306 qout->range[i].end =
307 (unsigned long) qout_old->range[i].end;
308 }
309 kfree(qout_old);
310 }
311#endif
312 if (qout->segcnt > 6) {
313 rc = -EOPNOTSUPP;
314 goto out_free;
315 }
316
317 if (qout->segcnt == 1) {
318 seg->vm_segtype = qout->range[0].start & 0xff;
319 } else {
320 /* multi-part segment. only one type supported here:
321 - all parts are contiguous
322 - all parts are either EW or EN type
323 - maximum 6 parts allowed */
324 unsigned long start = qout->segstart >> PAGE_SHIFT;
325 for (i=0; i<qout->segcnt; i++) {
326 if (((qout->range[i].start & 0xff) != SEG_TYPE_EW) &&
327 ((qout->range[i].start & 0xff) != SEG_TYPE_EN)) {
328 rc = -EOPNOTSUPP;
329 goto out_free;
330 }
331 if (start != qout->range[i].start >> PAGE_SHIFT) {
332 rc = -EOPNOTSUPP;
333 goto out_free;
334 }
335 start = (qout->range[i].end >> PAGE_SHIFT) + 1;
336 }
337 seg->vm_segtype = SEG_TYPE_EWEN;
338 }
339
340 /* analyze diag output and update seg */
341 seg->start_addr = qout->segstart;
342 seg->end = qout->segend;
343
344 memcpy (seg->range, qout->range, 6*sizeof(struct qrange));
345 seg->segcnt = qout->segcnt;
346
347 rc = 0;
348
349 out_free:
350 kfree(qin);
351 kfree(qout);
352 return rc;
353}
354
355/*
356 * get info about a segment
357 * possible return values:
358 * -ENOSYS : we are not running on VM
359 * -EIO : could not perform query diagnose
360 * -ENOENT : no such segment
361 * -EOPNOTSUPP: multi-part segment cannot be used with linux
362 * -ENOMEM : out of memory
363 * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
364 */
365int
366segment_type (char* name)
367{
368 int rc;
369 struct dcss_segment seg;
370
371 if (!MACHINE_IS_VM)
372 return -ENOSYS;
373
374 dcss_mkname(name, seg.dcss_name);
375 rc = query_segment_type (&seg);
376 if (rc < 0)
377 return rc;
378 return seg.vm_segtype;
379}
380
381/*
382 * check if segment collides with other segments that are currently loaded
383 * returns 1 if this is the case, 0 if no collision was found
384 */
385static int
386segment_overlaps_others (struct dcss_segment *seg)
387{
388 struct list_head *l;
389 struct dcss_segment *tmp;
390
391 BUG_ON(!mutex_is_locked(&dcss_lock));
392 list_for_each(l, &dcss_list) {
393 tmp = list_entry(l, struct dcss_segment, list);
394 if ((tmp->start_addr >> 20) > (seg->end >> 20))
395 continue;
396 if ((tmp->end >> 20) < (seg->start_addr >> 20))
397 continue;
398 if (seg == tmp)
399 continue;
400 return 1;
401 }
402 return 0;
403}
404
405/*
406 * real segment loading function, called from segment_load
407 */
408static int
409__segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
410{
411 unsigned long start_addr, end_addr, dummy;
412 struct dcss_segment *seg;
413 int rc, diag_cc;
414
415 start_addr = end_addr = 0;
416 seg = kmalloc(sizeof(*seg), GFP_KERNEL | GFP_DMA);
417 if (seg == NULL) {
418 rc = -ENOMEM;
419 goto out;
420 }
421 dcss_mkname (name, seg->dcss_name);
422 rc = query_segment_type (seg);
423 if (rc < 0)
424 goto out_free;
425
426 if (loadshr_scode == DCSS_LOADSHRX) {
427 if (segment_overlaps_others(seg)) {
428 rc = -EBUSY;
429 goto out_free;
430 }
431 }
432
433 rc = vmem_add_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
434
435 if (rc)
436 goto out_free;
437
438 seg->res = kzalloc(sizeof(struct resource), GFP_KERNEL);
439 if (seg->res == NULL) {
440 rc = -ENOMEM;
441 goto out_shared;
442 }
443 seg->res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
444 seg->res->start = seg->start_addr;
445 seg->res->end = seg->end;
446 memcpy(&seg->res_name, seg->dcss_name, 8);
447 EBCASC(seg->res_name, 8);
448 seg->res_name[8] = '\0';
449 strncat(seg->res_name, " (DCSS)", 7);
450 seg->res->name = seg->res_name;
451 rc = seg->vm_segtype;
452 if (rc == SEG_TYPE_SC ||
453 ((rc == SEG_TYPE_SR || rc == SEG_TYPE_ER) && !do_nonshared))
454 seg->res->flags |= IORESOURCE_READONLY;
455 if (request_resource(&iomem_resource, seg->res)) {
456 rc = -EBUSY;
457 kfree(seg->res);
458 goto out_shared;
459 }
460
461 if (do_nonshared)
462 diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
463 &start_addr, &end_addr);
464 else
465 diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
466 &start_addr, &end_addr);
467 if (diag_cc < 0) {
468 dcss_diag(&purgeseg_scode, seg->dcss_name,
469 &dummy, &dummy);
470 rc = diag_cc;
471 goto out_resource;
472 }
473 if (diag_cc > 1) {
474 pr_warning("Loading DCSS %s failed with rc=%ld\n", name,
475 end_addr);
476 rc = dcss_diag_translate_rc(end_addr);
477 dcss_diag(&purgeseg_scode, seg->dcss_name,
478 &dummy, &dummy);
479 goto out_resource;
480 }
481 seg->start_addr = start_addr;
482 seg->end = end_addr;
483 seg->do_nonshared = do_nonshared;
484 atomic_set(&seg->ref_count, 1);
485 list_add(&seg->list, &dcss_list);
486 *addr = seg->start_addr;
487 *end = seg->end;
488 if (do_nonshared)
489 pr_info("DCSS %s of range %p to %p and type %s loaded as "
490 "exclusive-writable\n", name, (void*) seg->start_addr,
491 (void*) seg->end, segtype_string[seg->vm_segtype]);
492 else {
493 pr_info("DCSS %s of range %p to %p and type %s loaded in "
494 "shared access mode\n", name, (void*) seg->start_addr,
495 (void*) seg->end, segtype_string[seg->vm_segtype]);
496 }
497 goto out;
498 out_resource:
499 release_resource(seg->res);
500 kfree(seg->res);
501 out_shared:
502 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
503 out_free:
504 kfree(seg);
505 out:
506 return rc;
507}
508
509/*
510 * this function loads a DCSS segment
511 * name : name of the DCSS
512 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
513 * 1 indicates that the dcss should be exclusive for this linux image
514 * addr : will be filled with start address of the segment
515 * end : will be filled with end address of the segment
516 * return values:
517 * -ENOSYS : we are not running on VM
518 * -EIO : could not perform query or load diagnose
519 * -ENOENT : no such segment
520 * -EOPNOTSUPP: multi-part segment cannot be used with linux
521 * -ENOSPC : segment cannot be used (overlaps with storage)
522 * -EBUSY : segment can temporarily not be used (overlaps with dcss)
523 * -ERANGE : segment cannot be used (exceeds kernel mapping range)
524 * -EPERM : segment is currently loaded with incompatible permissions
525 * -ENOMEM : out of memory
526 * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
527 */
528int
529segment_load (char *name, int do_nonshared, unsigned long *addr,
530 unsigned long *end)
531{
532 struct dcss_segment *seg;
533 int rc;
534
535 if (!MACHINE_IS_VM)
536 return -ENOSYS;
537
538 mutex_lock(&dcss_lock);
539 seg = segment_by_name (name);
540 if (seg == NULL)
541 rc = __segment_load (name, do_nonshared, addr, end);
542 else {
543 if (do_nonshared == seg->do_nonshared) {
544 atomic_inc(&seg->ref_count);
545 *addr = seg->start_addr;
546 *end = seg->end;
547 rc = seg->vm_segtype;
548 } else {
549 *addr = *end = 0;
550 rc = -EPERM;
551 }
552 }
553 mutex_unlock(&dcss_lock);
554 return rc;
555}
556
557/*
558 * this function modifies the shared state of a DCSS segment. note that
559 * name : name of the DCSS
560 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
561 * 1 indicates that the dcss should be exclusive for this linux image
562 * return values:
563 * -EIO : could not perform load diagnose (segment gone!)
564 * -ENOENT : no such segment (segment gone!)
565 * -EAGAIN : segment is in use by other exploiters, try later
566 * -EINVAL : no segment with the given name is currently loaded - name invalid
567 * -EBUSY : segment can temporarily not be used (overlaps with dcss)
568 * 0 : operation succeeded
569 */
570int
571segment_modify_shared (char *name, int do_nonshared)
572{
573 struct dcss_segment *seg;
574 unsigned long start_addr, end_addr, dummy;
575 int rc, diag_cc;
576
577 start_addr = end_addr = 0;
578 mutex_lock(&dcss_lock);
579 seg = segment_by_name (name);
580 if (seg == NULL) {
581 rc = -EINVAL;
582 goto out_unlock;
583 }
584 if (do_nonshared == seg->do_nonshared) {
585 pr_info("DCSS %s is already in the requested access "
586 "mode\n", name);
587 rc = 0;
588 goto out_unlock;
589 }
590 if (atomic_read (&seg->ref_count) != 1) {
591 pr_warning("DCSS %s is in use and cannot be reloaded\n",
592 name);
593 rc = -EAGAIN;
594 goto out_unlock;
595 }
596 release_resource(seg->res);
597 if (do_nonshared)
598 seg->res->flags &= ~IORESOURCE_READONLY;
599 else
600 if (seg->vm_segtype == SEG_TYPE_SR ||
601 seg->vm_segtype == SEG_TYPE_ER)
602 seg->res->flags |= IORESOURCE_READONLY;
603
604 if (request_resource(&iomem_resource, seg->res)) {
605 pr_warning("DCSS %s overlaps with used memory resources "
606 "and cannot be reloaded\n", name);
607 rc = -EBUSY;
608 kfree(seg->res);
609 goto out_del_mem;
610 }
611
612 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
613 if (do_nonshared)
614 diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
615 &start_addr, &end_addr);
616 else
617 diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
618 &start_addr, &end_addr);
619 if (diag_cc < 0) {
620 rc = diag_cc;
621 goto out_del_res;
622 }
623 if (diag_cc > 1) {
624 pr_warning("Reloading DCSS %s failed with rc=%ld\n", name,
625 end_addr);
626 rc = dcss_diag_translate_rc(end_addr);
627 goto out_del_res;
628 }
629 seg->start_addr = start_addr;
630 seg->end = end_addr;
631 seg->do_nonshared = do_nonshared;
632 rc = 0;
633 goto out_unlock;
634 out_del_res:
635 release_resource(seg->res);
636 kfree(seg->res);
637 out_del_mem:
638 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
639 list_del(&seg->list);
640 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
641 kfree(seg);
642 out_unlock:
643 mutex_unlock(&dcss_lock);
644 return rc;
645}
646
647/*
648 * Decrease the use count of a DCSS segment and remove
649 * it from the address space if nobody is using it
650 * any longer.
651 */
652void
653segment_unload(char *name)
654{
655 unsigned long dummy;
656 struct dcss_segment *seg;
657
658 if (!MACHINE_IS_VM)
659 return;
660
661 mutex_lock(&dcss_lock);
662 seg = segment_by_name (name);
663 if (seg == NULL) {
664 pr_err("Unloading unknown DCSS %s failed\n", name);
665 goto out_unlock;
666 }
667 if (atomic_dec_return(&seg->ref_count) != 0)
668 goto out_unlock;
669 release_resource(seg->res);
670 kfree(seg->res);
671 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
672 list_del(&seg->list);
673 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
674 kfree(seg);
675out_unlock:
676 mutex_unlock(&dcss_lock);
677}
678
679/*
680 * save segment content permanently
681 */
682void
683segment_save(char *name)
684{
685 struct dcss_segment *seg;
686 char cmd1[160];
687 char cmd2[80];
688 int i, response;
689
690 if (!MACHINE_IS_VM)
691 return;
692
693 mutex_lock(&dcss_lock);
694 seg = segment_by_name (name);
695
696 if (seg == NULL) {
697 pr_err("Saving unknown DCSS %s failed\n", name);
698 goto out;
699 }
700
701 sprintf(cmd1, "DEFSEG %s", name);
702 for (i=0; i<seg->segcnt; i++) {
703 sprintf(cmd1+strlen(cmd1), " %lX-%lX %s",
704 seg->range[i].start >> PAGE_SHIFT,
705 seg->range[i].end >> PAGE_SHIFT,
706 segtype_string[seg->range[i].start & 0xff]);
707 }
708 sprintf(cmd2, "SAVESEG %s", name);
709 response = 0;
710 cpcmd(cmd1, NULL, 0, &response);
711 if (response) {
712 pr_err("Saving a DCSS failed with DEFSEG response code "
713 "%i\n", response);
714 goto out;
715 }
716 cpcmd(cmd2, NULL, 0, &response);
717 if (response) {
718 pr_err("Saving a DCSS failed with SAVESEG response code "
719 "%i\n", response);
720 goto out;
721 }
722out:
723 mutex_unlock(&dcss_lock);
724}
725
726/*
727 * print appropriate error message for segment_load()/segment_type()
728 * return code
729 */
730void segment_warning(int rc, char *seg_name)
731{
732 switch (rc) {
733 case -ENOENT:
734 pr_err("DCSS %s cannot be loaded or queried\n", seg_name);
735 break;
736 case -ENOSYS:
737 pr_err("DCSS %s cannot be loaded or queried without "
738 "z/VM\n", seg_name);
739 break;
740 case -EIO:
741 pr_err("Loading or querying DCSS %s resulted in a "
742 "hardware error\n", seg_name);
743 break;
744 case -EOPNOTSUPP:
745 pr_err("DCSS %s has multiple page ranges and cannot be "
746 "loaded or queried\n", seg_name);
747 break;
748 case -ENOSPC:
749 pr_err("DCSS %s overlaps with used storage and cannot "
750 "be loaded\n", seg_name);
751 break;
752 case -EBUSY:
753 pr_err("%s needs used memory resources and cannot be "
754 "loaded or queried\n", seg_name);
755 break;
756 case -EPERM:
757 pr_err("DCSS %s is already loaded in a different access "
758 "mode\n", seg_name);
759 break;
760 case -ENOMEM:
761 pr_err("There is not enough memory to load or query "
762 "DCSS %s\n", seg_name);
763 break;
764 case -ERANGE:
765 pr_err("DCSS %s exceeds the kernel mapping range (%lu) "
766 "and cannot be loaded\n", seg_name, VMEM_MAX_PHYS);
767 break;
768 default:
769 break;
770 }
771}
772
773EXPORT_SYMBOL(segment_load);
774EXPORT_SYMBOL(segment_unload);
775EXPORT_SYMBOL(segment_save);
776EXPORT_SYMBOL(segment_type);
777EXPORT_SYMBOL(segment_modify_shared);
778EXPORT_SYMBOL(segment_warning);