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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 */
293static int
294__segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
295{
296 unsigned long start_addr, end_addr, dummy;
297 struct dcss_segment *seg;
298 int rc, diag_cc;
299
300 start_addr = end_addr = 0;
301 seg = kmalloc(sizeof(*seg), GFP_KERNEL | GFP_DMA);
302 if (seg == NULL) {
303 rc = -ENOMEM;
304 goto out;
305 }
306 dcss_mkname (name, seg->dcss_name);
307 rc = query_segment_type (seg);
308 if (rc < 0)
309 goto out_free;
310
311 if (segment_overlaps_others(seg)) {
312 rc = -EBUSY;
313 goto out_free;
314 }
315
316 seg->res = kzalloc(sizeof(struct resource), GFP_KERNEL);
317 if (seg->res == NULL) {
318 rc = -ENOMEM;
319 goto out_free;
320 }
321 seg->res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
322 seg->res->start = seg->start_addr;
323 seg->res->end = seg->end;
324 memcpy(&seg->res_name, seg->dcss_name, 8);
325 EBCASC(seg->res_name, 8);
326 seg->res_name[8] = '\0';
327 strlcat(seg->res_name, " (DCSS)", sizeof(seg->res_name));
328 seg->res->name = seg->res_name;
329 rc = seg->vm_segtype;
330 if (rc == SEG_TYPE_SC ||
331 ((rc == SEG_TYPE_SR || rc == SEG_TYPE_ER) && !do_nonshared))
332 seg->res->flags |= IORESOURCE_READONLY;
333
334 /* Check for overlapping resources before adding the mapping. */
335 if (request_resource(&iomem_resource, seg->res)) {
336 rc = -EBUSY;
337 goto out_free_resource;
338 }
339
340 rc = vmem_add_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
341 if (rc)
342 goto out_resource;
343
344 if (do_nonshared)
345 diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
346 &start_addr, &end_addr);
347 else
348 diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
349 &start_addr, &end_addr);
350 if (diag_cc < 0) {
351 dcss_diag(&purgeseg_scode, seg->dcss_name,
352 &dummy, &dummy);
353 rc = diag_cc;
354 goto out_mapping;
355 }
356 if (diag_cc > 1) {
357 pr_warn("Loading DCSS %s failed with rc=%ld\n", name, end_addr);
358 rc = dcss_diag_translate_rc(end_addr);
359 dcss_diag(&purgeseg_scode, seg->dcss_name,
360 &dummy, &dummy);
361 goto out_mapping;
362 }
363 seg->start_addr = start_addr;
364 seg->end = end_addr;
365 seg->do_nonshared = do_nonshared;
366 refcount_set(&seg->ref_count, 1);
367 list_add(&seg->list, &dcss_list);
368 *addr = seg->start_addr;
369 *end = seg->end;
370 if (do_nonshared)
371 pr_info("DCSS %s of range %px to %px and type %s loaded as "
372 "exclusive-writable\n", name, (void*) seg->start_addr,
373 (void*) seg->end, segtype_string[seg->vm_segtype]);
374 else {
375 pr_info("DCSS %s of range %px to %px and type %s loaded in "
376 "shared access mode\n", name, (void*) seg->start_addr,
377 (void*) seg->end, segtype_string[seg->vm_segtype]);
378 }
379 goto out;
380 out_mapping:
381 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
382 out_resource:
383 release_resource(seg->res);
384 out_free_resource:
385 kfree(seg->res);
386 out_free:
387 kfree(seg);
388 out:
389 return rc;
390}
391
392/*
393 * this function loads a DCSS segment
394 * name : name of the DCSS
395 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
396 * 1 indicates that the dcss should be exclusive for this linux image
397 * addr : will be filled with start address of the segment
398 * end : will be filled with end address of the segment
399 * return values:
400 * -ENOSYS : we are not running on VM
401 * -EIO : could not perform query or load diagnose
402 * -ENOENT : no such segment
403 * -EOPNOTSUPP: multi-part segment cannot be used with linux
404 * -EBUSY : segment cannot be used (overlaps with dcss or storage)
405 * -ERANGE : segment cannot be used (exceeds kernel mapping range)
406 * -EPERM : segment is currently loaded with incompatible permissions
407 * -ENOMEM : out of memory
408 * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
409 */
410int
411segment_load (char *name, int do_nonshared, unsigned long *addr,
412 unsigned long *end)
413{
414 struct dcss_segment *seg;
415 int rc;
416
417 if (!MACHINE_IS_VM)
418 return -ENOSYS;
419
420 mutex_lock(&dcss_lock);
421 seg = segment_by_name (name);
422 if (seg == NULL)
423 rc = __segment_load (name, do_nonshared, addr, end);
424 else {
425 if (do_nonshared == seg->do_nonshared) {
426 refcount_inc(&seg->ref_count);
427 *addr = seg->start_addr;
428 *end = seg->end;
429 rc = seg->vm_segtype;
430 } else {
431 *addr = *end = 0;
432 rc = -EPERM;
433 }
434 }
435 mutex_unlock(&dcss_lock);
436 return rc;
437}
438
439/*
440 * this function modifies the shared state of a DCSS segment. note that
441 * name : name of the DCSS
442 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
443 * 1 indicates that the dcss should be exclusive for this linux image
444 * return values:
445 * -EIO : could not perform load diagnose (segment gone!)
446 * -ENOENT : no such segment (segment gone!)
447 * -EAGAIN : segment is in use by other exploiters, try later
448 * -EINVAL : no segment with the given name is currently loaded - name invalid
449 * -EBUSY : segment can temporarily not be used (overlaps with dcss)
450 * 0 : operation succeeded
451 */
452int
453segment_modify_shared (char *name, int do_nonshared)
454{
455 struct dcss_segment *seg;
456 unsigned long start_addr, end_addr, dummy;
457 int rc, diag_cc;
458
459 start_addr = end_addr = 0;
460 mutex_lock(&dcss_lock);
461 seg = segment_by_name (name);
462 if (seg == NULL) {
463 rc = -EINVAL;
464 goto out_unlock;
465 }
466 if (do_nonshared == seg->do_nonshared) {
467 pr_info("DCSS %s is already in the requested access "
468 "mode\n", name);
469 rc = 0;
470 goto out_unlock;
471 }
472 if (refcount_read(&seg->ref_count) != 1) {
473 pr_warn("DCSS %s is in use and cannot be reloaded\n", name);
474 rc = -EAGAIN;
475 goto out_unlock;
476 }
477 release_resource(seg->res);
478 if (do_nonshared)
479 seg->res->flags &= ~IORESOURCE_READONLY;
480 else
481 if (seg->vm_segtype == SEG_TYPE_SR ||
482 seg->vm_segtype == SEG_TYPE_ER)
483 seg->res->flags |= IORESOURCE_READONLY;
484
485 if (request_resource(&iomem_resource, seg->res)) {
486 pr_warn("DCSS %s overlaps with used memory resources and cannot be reloaded\n",
487 name);
488 rc = -EBUSY;
489 kfree(seg->res);
490 goto out_del_mem;
491 }
492
493 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
494 if (do_nonshared)
495 diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
496 &start_addr, &end_addr);
497 else
498 diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
499 &start_addr, &end_addr);
500 if (diag_cc < 0) {
501 rc = diag_cc;
502 goto out_del_res;
503 }
504 if (diag_cc > 1) {
505 pr_warn("Reloading DCSS %s failed with rc=%ld\n",
506 name, end_addr);
507 rc = dcss_diag_translate_rc(end_addr);
508 goto out_del_res;
509 }
510 seg->start_addr = start_addr;
511 seg->end = end_addr;
512 seg->do_nonshared = do_nonshared;
513 rc = 0;
514 goto out_unlock;
515 out_del_res:
516 release_resource(seg->res);
517 kfree(seg->res);
518 out_del_mem:
519 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
520 list_del(&seg->list);
521 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
522 kfree(seg);
523 out_unlock:
524 mutex_unlock(&dcss_lock);
525 return rc;
526}
527
528/*
529 * Decrease the use count of a DCSS segment and remove
530 * it from the address space if nobody is using it
531 * any longer.
532 */
533void
534segment_unload(char *name)
535{
536 unsigned long dummy;
537 struct dcss_segment *seg;
538
539 if (!MACHINE_IS_VM)
540 return;
541
542 mutex_lock(&dcss_lock);
543 seg = segment_by_name (name);
544 if (seg == NULL) {
545 pr_err("Unloading unknown DCSS %s failed\n", name);
546 goto out_unlock;
547 }
548 if (!refcount_dec_and_test(&seg->ref_count))
549 goto out_unlock;
550 release_resource(seg->res);
551 kfree(seg->res);
552 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
553 list_del(&seg->list);
554 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
555 kfree(seg);
556out_unlock:
557 mutex_unlock(&dcss_lock);
558}
559
560/*
561 * save segment content permanently
562 */
563void
564segment_save(char *name)
565{
566 struct dcss_segment *seg;
567 char cmd1[160];
568 char cmd2[80];
569 int i, response;
570
571 if (!MACHINE_IS_VM)
572 return;
573
574 mutex_lock(&dcss_lock);
575 seg = segment_by_name (name);
576
577 if (seg == NULL) {
578 pr_err("Saving unknown DCSS %s failed\n", name);
579 goto out;
580 }
581
582 sprintf(cmd1, "DEFSEG %s", name);
583 for (i=0; i<seg->segcnt; i++) {
584 sprintf(cmd1+strlen(cmd1), " %lX-%lX %s",
585 seg->range[i].start >> PAGE_SHIFT,
586 seg->range[i].end >> PAGE_SHIFT,
587 segtype_string[seg->range[i].start & 0xff]);
588 }
589 sprintf(cmd2, "SAVESEG %s", name);
590 response = 0;
591 cpcmd(cmd1, NULL, 0, &response);
592 if (response) {
593 pr_err("Saving a DCSS failed with DEFSEG response code "
594 "%i\n", response);
595 goto out;
596 }
597 cpcmd(cmd2, NULL, 0, &response);
598 if (response) {
599 pr_err("Saving a DCSS failed with SAVESEG response code "
600 "%i\n", response);
601 goto out;
602 }
603out:
604 mutex_unlock(&dcss_lock);
605}
606
607/*
608 * print appropriate error message for segment_load()/segment_type()
609 * return code
610 */
611void segment_warning(int rc, char *seg_name)
612{
613 switch (rc) {
614 case -ENOENT:
615 pr_err("DCSS %s cannot be loaded or queried\n", seg_name);
616 break;
617 case -ENOSYS:
618 pr_err("DCSS %s cannot be loaded or queried without "
619 "z/VM\n", seg_name);
620 break;
621 case -EIO:
622 pr_err("Loading or querying DCSS %s resulted in a "
623 "hardware error\n", seg_name);
624 break;
625 case -EOPNOTSUPP:
626 pr_err("DCSS %s has multiple page ranges and cannot be "
627 "loaded or queried\n", seg_name);
628 break;
629 case -EBUSY:
630 pr_err("%s needs used memory resources and cannot be "
631 "loaded or queried\n", seg_name);
632 break;
633 case -EPERM:
634 pr_err("DCSS %s is already loaded in a different access "
635 "mode\n", seg_name);
636 break;
637 case -ENOMEM:
638 pr_err("There is not enough memory to load or query "
639 "DCSS %s\n", seg_name);
640 break;
641 case -ERANGE:
642 pr_err("DCSS %s exceeds the kernel mapping range (%lu) "
643 "and cannot be loaded\n", seg_name, VMEM_MAX_PHYS);
644 break;
645 default:
646 break;
647 }
648}
649
650EXPORT_SYMBOL(segment_load);
651EXPORT_SYMBOL(segment_unload);
652EXPORT_SYMBOL(segment_save);
653EXPORT_SYMBOL(segment_type);
654EXPORT_SYMBOL(segment_modify_shared);
655EXPORT_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);