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