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