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