blob: a9566bcab682b4bcb2bd83b565ae4aecbd07b830 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * File...........: arch/s390/mm/extmem.c
3 * Author(s)......: Carsten Otte <cotte@de.ibm.com>
4 * Rob M van der Heij <rvdheij@nl.ibm.com>
5 * Steven Shultz <shultzss@us.ibm.com>
6 * Bugreports.to..: <Linux390@de.ibm.com>
7 * (C) IBM Corporation 2002-2004
8 */
9
10#include <linux/kernel.h>
11#include <linux/string.h>
12#include <linux/spinlock.h>
13#include <linux/list.h>
14#include <linux/slab.h>
15#include <linux/module.h>
16#include <linux/bootmem.h>
17#include <asm/page.h>
18#include <asm/ebcdic.h>
19#include <asm/errno.h>
20#include <asm/extmem.h>
21#include <asm/cpcmd.h>
22#include <linux/ctype.h>
23
24#define DCSS_DEBUG /* Debug messages on/off */
25
26#define DCSS_NAME "extmem"
27#ifdef DCSS_DEBUG
28#define PRINT_DEBUG(x...) printk(KERN_DEBUG DCSS_NAME " debug:" x)
29#else
30#define PRINT_DEBUG(x...) do {} while (0)
31#endif
32#define PRINT_INFO(x...) printk(KERN_INFO DCSS_NAME " info:" x)
33#define PRINT_WARN(x...) printk(KERN_WARNING DCSS_NAME " warning:" x)
34#define PRINT_ERR(x...) printk(KERN_ERR DCSS_NAME " error:" x)
35
36
37#define DCSS_LOADSHR 0x00
38#define DCSS_LOADNSR 0x04
39#define DCSS_PURGESEG 0x08
40#define DCSS_FINDSEG 0x0c
41#define DCSS_LOADNOLY 0x10
42#define DCSS_SEGEXT 0x18
43#define DCSS_FINDSEGA 0x0c
44
45struct qrange {
46 unsigned int start; // 3byte start address, 1 byte type
47 unsigned int end; // 3byte end address, 1 byte reserved
48};
49
50struct qout64 {
51 int segstart;
52 int segend;
53 int segcnt;
54 int segrcnt;
55 struct qrange range[6];
56};
57
58struct qin64 {
59 char qopcode;
60 char rsrv1[3];
61 char qrcode;
62 char rsrv2[3];
63 char qname[8];
64 unsigned int qoutptr;
65 short int qoutlen;
66};
67
68struct dcss_segment {
69 struct list_head list;
70 char dcss_name[8];
71 unsigned long start_addr;
72 unsigned long end;
73 atomic_t ref_count;
74 int do_nonshared;
75 unsigned int vm_segtype;
76 struct qrange range[6];
77 int segcnt;
78};
79
80static DEFINE_SPINLOCK(dcss_lock);
81static struct list_head dcss_list = LIST_HEAD_INIT(dcss_list);
82static char *segtype_string[] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC",
83 "EW/EN-MIXED" };
84
85extern struct {
86 unsigned long addr, size, type;
87} memory_chunk[MEMORY_CHUNKS];
88
89/*
90 * Create the 8 bytes, ebcdic VM segment name from
91 * an ascii name.
92 */
93static void inline
94dcss_mkname(char *name, char *dcss_name)
95{
96 int i;
97
98 for (i = 0; i < 8; i++) {
99 if (name[i] == '\0')
100 break;
101 dcss_name[i] = toupper(name[i]);
102 };
103 for (; i < 8; i++)
104 dcss_name[i] = ' ';
105 ASCEBC(dcss_name, 8);
106}
107
108
109/*
110 * search all segments in dcss_list, and return the one
111 * namend *name. If not found, return NULL.
112 */
113static struct dcss_segment *
114segment_by_name (char *name)
115{
116 char dcss_name[9];
117 struct list_head *l;
118 struct dcss_segment *tmp, *retval = NULL;
119
120 assert_spin_locked(&dcss_lock);
121 dcss_mkname (name, dcss_name);
122 list_for_each (l, &dcss_list) {
123 tmp = list_entry (l, struct dcss_segment, list);
124 if (memcmp(tmp->dcss_name, dcss_name, 8) == 0) {
125 retval = tmp;
126 break;
127 }
128 }
129 return retval;
130}
131
132
133/*
134 * Perform a function on a dcss segment.
135 */
136static inline int
137dcss_diag (__u8 func, void *parameter,
138 unsigned long *ret1, unsigned long *ret2)
139{
140 unsigned long rx, ry;
141 int rc;
142
143 rx = (unsigned long) parameter;
144 ry = (unsigned long) func;
145 __asm__ __volatile__(
Martin Schwidefsky347a8dc2006-01-06 00:19:28 -0800146#ifdef CONFIG_64BIT
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147 " sam31\n" // switch to 31 bit
148 " diag %0,%1,0x64\n"
149 " sam64\n" // switch back to 64 bit
150#else
151 " diag %0,%1,0x64\n"
152#endif
153 " ipm %2\n"
154 " srl %2,28\n"
155 : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc" );
156 *ret1 = rx;
157 *ret2 = ry;
158 return rc;
159}
160
161static inline int
162dcss_diag_translate_rc (int vm_rc) {
163 if (vm_rc == 44)
164 return -ENOENT;
165 return -EIO;
166}
167
168
169/* do a diag to get info about a segment.
170 * fills start_address, end and vm_segtype fields
171 */
172static int
173query_segment_type (struct dcss_segment *seg)
174{
175 struct qin64 *qin = kmalloc (sizeof(struct qin64), GFP_DMA);
176 struct qout64 *qout = kmalloc (sizeof(struct qout64), GFP_DMA);
177
178 int diag_cc, rc, i;
179 unsigned long dummy, vmrc;
180
181 if ((qin == NULL) || (qout == NULL)) {
182 rc = -ENOMEM;
183 goto out_free;
184 }
185
186 /* initialize diag input parameters */
187 qin->qopcode = DCSS_FINDSEGA;
188 qin->qoutptr = (unsigned long) qout;
189 qin->qoutlen = sizeof(struct qout64);
190 memcpy (qin->qname, seg->dcss_name, 8);
191
192 diag_cc = dcss_diag (DCSS_SEGEXT, qin, &dummy, &vmrc);
193
194 if (diag_cc > 1) {
195 rc = dcss_diag_translate_rc (vmrc);
196 goto out_free;
197 }
198
199 if (qout->segcnt > 6) {
200 rc = -ENOTSUPP;
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 = -ENOTSUPP;
216 goto out_free;
217 }
218 if (start != qout->range[i].start >> PAGE_SHIFT) {
219 rc = -ENOTSUPP;
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:
Jesper Juhlb2325fe2005-11-07 01:01:35 -0800237 kfree(qin);
238 kfree(qout);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 return rc;
240}
241
242/*
243 * check if the given segment collides with guest storage.
244 * returns 1 if this is the case, 0 if no collision was found
245 */
246static int
247segment_overlaps_storage(struct dcss_segment *seg)
248{
249 int i;
250
251 for (i=0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
252 if (memory_chunk[i].type != 0)
253 continue;
254 if ((memory_chunk[i].addr >> 20) > (seg->end >> 20))
255 continue;
256 if (((memory_chunk[i].addr + memory_chunk[i].size - 1) >> 20)
257 < (seg->start_addr >> 20))
258 continue;
259 return 1;
260 }
261 return 0;
262}
263
264/*
265 * check if segment collides with other segments that are currently loaded
266 * returns 1 if this is the case, 0 if no collision was found
267 */
268static int
269segment_overlaps_others (struct dcss_segment *seg)
270{
271 struct list_head *l;
272 struct dcss_segment *tmp;
273
274 assert_spin_locked(&dcss_lock);
275 list_for_each(l, &dcss_list) {
276 tmp = list_entry(l, struct dcss_segment, list);
277 if ((tmp->start_addr >> 20) > (seg->end >> 20))
278 continue;
279 if ((tmp->end >> 20) < (seg->start_addr >> 20))
280 continue;
281 if (seg == tmp)
282 continue;
283 return 1;
284 }
285 return 0;
286}
287
288/*
289 * check if segment exceeds the kernel mapping range (detected or set via mem=)
290 * returns 1 if this is the case, 0 if segment fits into the range
291 */
292static inline int
293segment_exceeds_range (struct dcss_segment *seg)
294{
295 int seg_last_pfn = (seg->end) >> PAGE_SHIFT;
296 if (seg_last_pfn > max_pfn)
297 return 1;
298 return 0;
299}
300
301/*
302 * get info about a segment
303 * possible return values:
304 * -ENOSYS : we are not running on VM
305 * -EIO : could not perform query diagnose
306 * -ENOENT : no such segment
307 * -ENOTSUPP: multi-part segment cannot be used with linux
308 * -ENOSPC : segment cannot be used (overlaps with storage)
309 * -ENOMEM : out of memory
310 * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
311 */
312int
313segment_type (char* name)
314{
315 int rc;
316 struct dcss_segment seg;
317
318 if (!MACHINE_IS_VM)
319 return -ENOSYS;
320
321 dcss_mkname(name, seg.dcss_name);
322 rc = query_segment_type (&seg);
323 if (rc < 0)
324 return rc;
325 return seg.vm_segtype;
326}
327
328/*
329 * real segment loading function, called from segment_load
330 */
331static int
332__segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
333{
334 struct dcss_segment *seg = kmalloc(sizeof(struct dcss_segment),
335 GFP_DMA);
336 int dcss_command, rc, diag_cc;
337
338 if (seg == NULL) {
339 rc = -ENOMEM;
340 goto out;
341 }
342 dcss_mkname (name, seg->dcss_name);
343 rc = query_segment_type (seg);
344 if (rc < 0)
345 goto out_free;
346 if (segment_exceeds_range(seg)) {
347 PRINT_WARN ("segment_load: not loading segment %s - exceeds"
348 " kernel mapping range\n",name);
349 rc = -ERANGE;
350 goto out_free;
351 }
352 if (segment_overlaps_storage(seg)) {
353 PRINT_WARN ("segment_load: not loading segment %s - overlaps"
354 " storage\n",name);
355 rc = -ENOSPC;
356 goto out_free;
357 }
358 if (segment_overlaps_others(seg)) {
359 PRINT_WARN ("segment_load: not loading segment %s - overlaps"
360 " other segments\n",name);
361 rc = -EBUSY;
362 goto out_free;
363 }
364 if (do_nonshared)
365 dcss_command = DCSS_LOADNSR;
366 else
367 dcss_command = DCSS_LOADNOLY;
368
369 diag_cc = dcss_diag(dcss_command, seg->dcss_name,
370 &seg->start_addr, &seg->end);
371 if (diag_cc > 1) {
372 PRINT_WARN ("segment_load: could not load segment %s - "
373 "diag returned error (%ld)\n",name,seg->end);
374 rc = dcss_diag_translate_rc (seg->end);
375 dcss_diag(DCSS_PURGESEG, seg->dcss_name,
376 &seg->start_addr, &seg->end);
377 goto out_free;
378 }
379 seg->do_nonshared = do_nonshared;
380 atomic_set(&seg->ref_count, 1);
381 list_add(&seg->list, &dcss_list);
382 rc = seg->vm_segtype;
383 *addr = seg->start_addr;
384 *end = seg->end;
385 if (do_nonshared)
386 PRINT_INFO ("segment_load: loaded segment %s range %p .. %p "
387 "type %s in non-shared mode\n", name,
388 (void*)seg->start_addr, (void*)seg->end,
389 segtype_string[seg->vm_segtype]);
390 else
391 PRINT_INFO ("segment_load: loaded segment %s range %p .. %p "
392 "type %s in shared mode\n", name,
393 (void*)seg->start_addr, (void*)seg->end,
394 segtype_string[seg->vm_segtype]);
395 goto out;
396 out_free:
Jesper Juhlb2325fe2005-11-07 01:01:35 -0800397 kfree(seg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 out:
399 return rc;
400}
401
402/*
403 * this function loads a DCSS segment
404 * name : name of the DCSS
405 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
406 * 1 indicates that the dcss should be exclusive for this linux image
407 * addr : will be filled with start address of the segment
408 * end : will be filled with end address of the segment
409 * return values:
410 * -ENOSYS : we are not running on VM
411 * -EIO : could not perform query or load diagnose
412 * -ENOENT : no such segment
413 * -ENOTSUPP: multi-part segment cannot be used with linux
414 * -ENOSPC : segment cannot be used (overlaps with storage)
415 * -EBUSY : segment can temporarily not be used (overlaps with dcss)
416 * -ERANGE : segment cannot be used (exceeds kernel mapping range)
417 * -EPERM : segment is currently loaded with incompatible permissions
418 * -ENOMEM : out of memory
419 * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
420 */
421int
422segment_load (char *name, int do_nonshared, unsigned long *addr,
423 unsigned long *end)
424{
425 struct dcss_segment *seg;
426 int rc;
427
428 if (!MACHINE_IS_VM)
429 return -ENOSYS;
430
431 spin_lock (&dcss_lock);
432 seg = segment_by_name (name);
433 if (seg == NULL)
434 rc = __segment_load (name, do_nonshared, addr, end);
435 else {
436 if (do_nonshared == seg->do_nonshared) {
437 atomic_inc(&seg->ref_count);
438 *addr = seg->start_addr;
439 *end = seg->end;
440 rc = seg->vm_segtype;
441 } else {
442 *addr = *end = 0;
443 rc = -EPERM;
444 }
445 }
446 spin_unlock (&dcss_lock);
447 return rc;
448}
449
450/*
451 * this function modifies the shared state of a DCSS segment. note that
452 * name : name of the DCSS
453 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
454 * 1 indicates that the dcss should be exclusive for this linux image
455 * return values:
456 * -EIO : could not perform load diagnose (segment gone!)
457 * -ENOENT : no such segment (segment gone!)
458 * -EAGAIN : segment is in use by other exploiters, try later
459 * -EINVAL : no segment with the given name is currently loaded - name invalid
460 * 0 : operation succeeded
461 */
462int
463segment_modify_shared (char *name, int do_nonshared)
464{
465 struct dcss_segment *seg;
466 unsigned long dummy;
467 int dcss_command, rc, diag_cc;
468
469 spin_lock (&dcss_lock);
470 seg = segment_by_name (name);
471 if (seg == NULL) {
472 rc = -EINVAL;
473 goto out_unlock;
474 }
475 if (do_nonshared == seg->do_nonshared) {
476 PRINT_INFO ("segment_modify_shared: not reloading segment %s"
477 " - already in requested mode\n",name);
478 rc = 0;
479 goto out_unlock;
480 }
481 if (atomic_read (&seg->ref_count) != 1) {
482 PRINT_WARN ("segment_modify_shared: not reloading segment %s - "
483 "segment is in use by other driver(s)\n",name);
484 rc = -EAGAIN;
485 goto out_unlock;
486 }
487 dcss_diag(DCSS_PURGESEG, seg->dcss_name,
488 &dummy, &dummy);
489 if (do_nonshared)
490 dcss_command = DCSS_LOADNSR;
491 else
492 dcss_command = DCSS_LOADNOLY;
493 diag_cc = dcss_diag(dcss_command, seg->dcss_name,
494 &seg->start_addr, &seg->end);
495 if (diag_cc > 1) {
496 PRINT_WARN ("segment_modify_shared: could not reload segment %s"
497 " - diag returned error (%ld)\n",name,seg->end);
498 rc = dcss_diag_translate_rc (seg->end);
499 goto out_del;
500 }
501 seg->do_nonshared = do_nonshared;
502 rc = 0;
503 goto out_unlock;
504 out_del:
505 list_del(&seg->list);
506 dcss_diag(DCSS_PURGESEG, seg->dcss_name,
507 &dummy, &dummy);
Jesper Juhlb2325fe2005-11-07 01:01:35 -0800508 kfree(seg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509 out_unlock:
510 spin_unlock(&dcss_lock);
511 return rc;
512}
513
514/*
515 * Decrease the use count of a DCSS segment and remove
516 * it from the address space if nobody is using it
517 * any longer.
518 */
519void
520segment_unload(char *name)
521{
522 unsigned long dummy;
523 struct dcss_segment *seg;
524
525 if (!MACHINE_IS_VM)
526 return;
527
528 spin_lock(&dcss_lock);
529 seg = segment_by_name (name);
530 if (seg == NULL) {
531 PRINT_ERR ("could not find segment %s in segment_unload, "
532 "please report to linux390@de.ibm.com\n",name);
533 goto out_unlock;
534 }
535 if (atomic_dec_return(&seg->ref_count) == 0) {
536 list_del(&seg->list);
537 dcss_diag(DCSS_PURGESEG, seg->dcss_name,
538 &dummy, &dummy);
539 kfree(seg);
540 }
541out_unlock:
542 spin_unlock(&dcss_lock);
543}
544
545/*
546 * save segment content permanently
547 */
548void
549segment_save(char *name)
550{
551 struct dcss_segment *seg;
552 int startpfn = 0;
553 int endpfn = 0;
554 char cmd1[160];
555 char cmd2[80];
556 int i;
557
558 if (!MACHINE_IS_VM)
559 return;
560
561 spin_lock(&dcss_lock);
562 seg = segment_by_name (name);
563
564 if (seg == NULL) {
565 PRINT_ERR ("could not find segment %s in segment_save, please report to linux390@de.ibm.com\n",name);
566 return;
567 }
568
569 startpfn = seg->start_addr >> PAGE_SHIFT;
570 endpfn = (seg->end) >> PAGE_SHIFT;
571 sprintf(cmd1, "DEFSEG %s", name);
572 for (i=0; i<seg->segcnt; i++) {
573 sprintf(cmd1+strlen(cmd1), " %X-%X %s",
574 seg->range[i].start >> PAGE_SHIFT,
575 seg->range[i].end >> PAGE_SHIFT,
576 segtype_string[seg->range[i].start & 0xff]);
577 }
578 sprintf(cmd2, "SAVESEG %s", name);
Christian Borntraeger6b979de2005-06-25 14:55:32 -0700579 cpcmd(cmd1, NULL, 0, NULL);
580 cpcmd(cmd2, NULL, 0, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 spin_unlock(&dcss_lock);
582}
583
584EXPORT_SYMBOL(segment_load);
585EXPORT_SYMBOL(segment_unload);
586EXPORT_SYMBOL(segment_save);
587EXPORT_SYMBOL(segment_type);
588EXPORT_SYMBOL(segment_modify_shared);