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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/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);