1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #pragma ident "%Z%%M% %I% %E% SMI"
28
29 /*
30 * gnttab.c
31 *
32 * Granting foreign access to our memory reservation.
33 *
34 * Copyright (c) 2005-2006, Christopher Clark
35 * Copyright (c) 2004-2005, K A Fraser
36 *
37 * This program is free software; you can redistribute it and/or
38 * modify it under the terms of the GNU General Public License version 2
39 * as published by the Free Software Foundation; or, when distributed
40 * separately from the Linux kernel or incorporated into other
41 * software packages, subject to the following license:
42 *
43 * Permission is hereby granted, free of charge, to any person obtaining a copy
44 * of this source file (the "Software"), to deal in the Software without
45 * restriction, including without limitation the rights to use, copy, modify,
46 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
47 * and to permit persons to whom the Software is furnished to do so, subject to
48 * the following conditions:
49 *
50 * The above copyright notice and this permission notice shall be included in
51 * all copies or substantial portions of the Software.
52 *
53 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
54 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
55 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
56 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
57 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
58 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
59 * IN THE SOFTWARE.
60 */
61
62 #include <sys/types.h>
63 #include <sys/archsystm.h>
64 #ifdef XPV_HVM_DRIVER
65 #include <sys/xpv_support.h>
66 #include <sys/mman.h>
67 #include <vm/hat.h>
68 #endif
69 #include <sys/hypervisor.h>
70 #include <sys/gnttab.h>
71 #include <sys/sysmacros.h>
72 #include <sys/machsystm.h>
73 #include <sys/systm.h>
74 #include <sys/mutex.h>
75 #include <sys/atomic.h>
76 #include <sys/spl.h>
77 #include <sys/condvar.h>
78 #include <sys/cpuvar.h>
79 #include <sys/taskq.h>
80 #include <sys/panic.h>
81 #include <sys/cmn_err.h>
82 #include <sys/promif.h>
83 #include <sys/cpu.h>
84 #include <sys/vmem.h>
85 #include <vm/hat_i86.h>
86 #include <sys/bootconf.h>
87 #include <sys/bootsvcs.h>
88 #ifndef XPV_HVM_DRIVER
89 #include <sys/bootinfo.h>
90 #include <sys/multiboot.h>
91 #include <vm/kboot_mmu.h>
92 #endif
93 #include <sys/bootvfs.h>
94 #include <sys/bootprops.h>
95 #include <vm/seg_kmem.h>
96 #include <sys/mman.h>
97
98 /* Globals */
99
100 static grant_ref_t **gnttab_list;
101 static uint_t nr_grant_frames;
102 static int gnttab_free_count;
103 static grant_ref_t gnttab_free_head;
104 static kmutex_t gnttab_list_lock;
105 static grant_entry_t *shared;
106 static struct gnttab_free_callback *gnttab_free_callback_list;
107
108 /* Macros */
109
110 #define GT_PGADDR(i) ((uintptr_t)shared + ((i) << MMU_PAGESHIFT))
111 #define VALID_GRANT_REF(r) ((r) < (nr_grant_frames * GREFS_PER_GRANT_FRAME))
112 #define RPP (PAGESIZE / sizeof (grant_ref_t))
113 #define GNTTAB_ENTRY(entry) (gnttab_list[(entry) / RPP][(entry) % RPP])
114 #define CMPXCHG(t, c, n) atomic_cas_16((t), (c), (n))
115 /* External tools reserve first few grant table entries. */
116 #define NR_RESERVED_ENTRIES 8
117 #define GNTTAB_LIST_END 0xffffffff
118 #define GREFS_PER_GRANT_FRAME (PAGESIZE / sizeof (grant_entry_t))
119
120 /* Implementation */
121
122 static uint_t
max_nr_grant_frames(void)123 max_nr_grant_frames(void)
124 {
125 struct gnttab_query_size query;
126 int rc;
127
128 query.dom = DOMID_SELF;
129
130 rc = HYPERVISOR_grant_table_op(GNTTABOP_query_size, &query, 1);
131 if ((rc < 0) || (query.status != GNTST_okay))
132 return (4); /* Legacy max supported number of frames */
133
134 ASSERT(query.max_nr_frames);
135 return (query.max_nr_frames);
136 }
137
138 static void
do_free_callbacks(void)139 do_free_callbacks(void)
140 {
141 struct gnttab_free_callback *callback, *next;
142
143 callback = gnttab_free_callback_list;
144 gnttab_free_callback_list = NULL;
145
146 while (callback != NULL) {
147 next = callback->next;
148 if (gnttab_free_count >= callback->count) {
149 callback->next = NULL;
150 callback->fn(callback->arg);
151 } else {
152 callback->next = gnttab_free_callback_list;
153 gnttab_free_callback_list = callback;
154 }
155 callback = next;
156 }
157 }
158
159 static void
check_free_callbacks(void)160 check_free_callbacks(void)
161 {
162 if (gnttab_free_callback_list)
163 do_free_callbacks();
164 }
165
166 static int
grow_gnttab_list(uint_t more_frames)167 grow_gnttab_list(uint_t more_frames)
168 {
169 uint_t new_nr_grant_frames, extra_entries, i;
170 uint_t nr_glist_frames, new_nr_glist_frames;
171
172 ASSERT(MUTEX_HELD(&gnttab_list_lock));
173
174 new_nr_grant_frames = nr_grant_frames + more_frames;
175 extra_entries = more_frames * GREFS_PER_GRANT_FRAME;
176
177 nr_glist_frames = (nr_grant_frames * GREFS_PER_GRANT_FRAME + RPP - 1)
178 / RPP;
179 new_nr_glist_frames = (new_nr_grant_frames * GREFS_PER_GRANT_FRAME
180 + RPP - 1) / RPP;
181 for (i = nr_glist_frames; i < new_nr_glist_frames; i++)
182 gnttab_list[i] = kmem_alloc(PAGESIZE, KM_SLEEP);
183
184 for (i = GREFS_PER_GRANT_FRAME * nr_grant_frames;
185 i < GREFS_PER_GRANT_FRAME * new_nr_grant_frames - 1; i++)
186 GNTTAB_ENTRY(i) = i + 1;
187
188 GNTTAB_ENTRY(i) = gnttab_free_head;
189 gnttab_free_head = GREFS_PER_GRANT_FRAME * nr_grant_frames;
190 gnttab_free_count += extra_entries;
191
192 nr_grant_frames = new_nr_grant_frames;
193
194 check_free_callbacks();
195
196 return (0);
197 }
198
199 static int
gnttab_expand(uint_t req_entries)200 gnttab_expand(uint_t req_entries)
201 {
202 uint_t cur, extra;
203
204 ASSERT(MUTEX_HELD(&gnttab_list_lock));
205
206 cur = nr_grant_frames;
207 extra = ((req_entries + (GREFS_PER_GRANT_FRAME - 1)) /
208 GREFS_PER_GRANT_FRAME);
209 if (cur + extra > max_nr_grant_frames())
210 return (-1);
211
212 return (grow_gnttab_list(extra));
213 }
214
215 static int
get_free_entries(int count)216 get_free_entries(int count)
217 {
218 int ref, rc;
219 grant_ref_t head;
220
221 mutex_enter(&gnttab_list_lock);
222 if (gnttab_free_count < count &&
223 ((rc = gnttab_expand(count - gnttab_free_count)) < 0)) {
224 mutex_exit(&gnttab_list_lock);
225 return (rc);
226 }
227 ref = head = gnttab_free_head;
228 gnttab_free_count -= count;
229 while (count-- > 1)
230 head = GNTTAB_ENTRY(head);
231 gnttab_free_head = GNTTAB_ENTRY(head);
232 GNTTAB_ENTRY(head) = GNTTAB_LIST_END;
233 mutex_exit(&gnttab_list_lock);
234 return (ref);
235 }
236
237 static void
put_free_entry(grant_ref_t ref)238 put_free_entry(grant_ref_t ref)
239 {
240 ASSERT(VALID_GRANT_REF(ref));
241
242 mutex_enter(&gnttab_list_lock);
243 GNTTAB_ENTRY(ref) = gnttab_free_head;
244 gnttab_free_head = ref;
245 gnttab_free_count++;
246 check_free_callbacks();
247 mutex_exit(&gnttab_list_lock);
248 }
249
250 /*
251 * Public grant-issuing interface functions
252 */
253
254 int
gnttab_grant_foreign_access(domid_t domid,gnttab_frame_t frame,int readonly)255 gnttab_grant_foreign_access(domid_t domid, gnttab_frame_t frame, int readonly)
256 {
257 int ref;
258
259 if ((ref = get_free_entries(1)) == -1)
260 return (-1);
261
262 ASSERT(VALID_GRANT_REF(ref));
263
264 shared[ref].frame = frame;
265 shared[ref].domid = domid;
266 membar_producer();
267 shared[ref].flags = GTF_permit_access | (readonly ? GTF_readonly : 0);
268
269 return (ref);
270 }
271
272 void
gnttab_grant_foreign_access_ref(grant_ref_t ref,domid_t domid,gnttab_frame_t frame,int readonly)273 gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
274 gnttab_frame_t frame, int readonly)
275 {
276 ASSERT(VALID_GRANT_REF(ref));
277
278 shared[ref].frame = frame;
279 shared[ref].domid = domid;
280 membar_producer();
281 shared[ref].flags = GTF_permit_access | (readonly ? GTF_readonly : 0);
282 }
283
284
285 int
gnttab_query_foreign_access(grant_ref_t ref)286 gnttab_query_foreign_access(grant_ref_t ref)
287 {
288 uint16_t nflags;
289
290 ASSERT(VALID_GRANT_REF(ref));
291
292 nflags = shared[ref].flags;
293
294 return (nflags & (GTF_reading|GTF_writing));
295 }
296
297 /* ARGSUSED */
298 int
gnttab_end_foreign_access_ref(grant_ref_t ref,int readonly)299 gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
300 {
301 uint16_t flags, nflags;
302
303 ASSERT(VALID_GRANT_REF(ref));
304
305 nflags = shared[ref].flags;
306 do {
307 if ((flags = nflags) & (GTF_reading|GTF_writing)) {
308 cmn_err(CE_WARN, "g.e. still in use!");
309 return (0);
310 }
311 } while ((nflags = CMPXCHG(&shared[ref].flags, flags, 0)) != flags);
312
313 return (1);
314 }
315
316 void
gnttab_end_foreign_access(grant_ref_t ref,int readonly,gnttab_frame_t page)317 gnttab_end_foreign_access(grant_ref_t ref, int readonly, gnttab_frame_t page)
318 {
319 ASSERT(VALID_GRANT_REF(ref));
320
321 if (gnttab_end_foreign_access_ref(ref, readonly)) {
322 put_free_entry(ref);
323 /*
324 * XXPV - we don't support freeing a page here
325 */
326 if (page != 0) {
327 cmn_err(CE_WARN,
328 "gnttab_end_foreign_access_ref: using unsupported free_page interface");
329 /* free_page(page); */
330 }
331 } else {
332 /*
333 * XXX This needs to be fixed so that the ref and page are
334 * placed on a list to be freed up later.
335 */
336 cmn_err(CE_WARN, "leaking g.e. and page still in use!");
337 }
338 }
339
340 int
gnttab_grant_foreign_transfer(domid_t domid,pfn_t pfn)341 gnttab_grant_foreign_transfer(domid_t domid, pfn_t pfn)
342 {
343 int ref;
344
345 if ((ref = get_free_entries(1)) == -1)
346 return (-1);
347
348 ASSERT(VALID_GRANT_REF(ref));
349
350 gnttab_grant_foreign_transfer_ref(ref, domid, pfn);
351
352 return (ref);
353 }
354
355 void
gnttab_grant_foreign_transfer_ref(grant_ref_t ref,domid_t domid,pfn_t pfn)356 gnttab_grant_foreign_transfer_ref(grant_ref_t ref, domid_t domid, pfn_t pfn)
357 {
358 ASSERT(VALID_GRANT_REF(ref));
359
360 shared[ref].frame = pfn;
361 shared[ref].domid = domid;
362 membar_producer();
363 shared[ref].flags = GTF_accept_transfer;
364 }
365
366 gnttab_frame_t
gnttab_end_foreign_transfer_ref(grant_ref_t ref)367 gnttab_end_foreign_transfer_ref(grant_ref_t ref)
368 {
369 gnttab_frame_t frame;
370 uint16_t flags;
371
372 ASSERT(VALID_GRANT_REF(ref));
373
374 /*
375 * If a transfer is not even yet started, try to reclaim the grant
376 * reference and return failure (== 0).
377 */
378 while (!((flags = shared[ref].flags) & GTF_transfer_committed)) {
379 if (CMPXCHG(&shared[ref].flags, flags, 0) == flags)
380 return (0);
381 (void) HYPERVISOR_yield();
382 }
383
384 /* If a transfer is in progress then wait until it is completed. */
385 while (!(flags & GTF_transfer_completed)) {
386 flags = shared[ref].flags;
387 (void) HYPERVISOR_yield();
388 }
389
390 /* Read the frame number /after/ reading completion status. */
391 membar_consumer();
392 frame = shared[ref].frame;
393 ASSERT(frame != 0);
394
395 return (frame);
396 }
397
398 gnttab_frame_t
gnttab_end_foreign_transfer(grant_ref_t ref)399 gnttab_end_foreign_transfer(grant_ref_t ref)
400 {
401 gnttab_frame_t frame;
402
403 ASSERT(VALID_GRANT_REF(ref));
404
405 frame = gnttab_end_foreign_transfer_ref(ref);
406 put_free_entry(ref);
407 return (frame);
408 }
409
410 void
gnttab_free_grant_reference(grant_ref_t ref)411 gnttab_free_grant_reference(grant_ref_t ref)
412 {
413 ASSERT(VALID_GRANT_REF(ref));
414
415 put_free_entry(ref);
416 }
417
418 void
gnttab_free_grant_references(grant_ref_t head)419 gnttab_free_grant_references(grant_ref_t head)
420 {
421 grant_ref_t ref;
422 int count = 1;
423
424 if (head == GNTTAB_LIST_END)
425 return;
426 mutex_enter(&gnttab_list_lock);
427 ref = head;
428 while (GNTTAB_ENTRY(ref) != GNTTAB_LIST_END) {
429 ref = GNTTAB_ENTRY(ref);
430 count++;
431 }
432 GNTTAB_ENTRY(ref) = gnttab_free_head;
433 gnttab_free_head = head;
434 gnttab_free_count += count;
435 check_free_callbacks();
436 mutex_exit(&gnttab_list_lock);
437 }
438
439 int
gnttab_alloc_grant_references(uint16_t count,grant_ref_t * head)440 gnttab_alloc_grant_references(uint16_t count, grant_ref_t *head)
441 {
442 int h = get_free_entries(count);
443
444 if (h == -1)
445 return (-1);
446
447 *head = h;
448
449 return (0);
450 }
451
452 int
gnttab_empty_grant_references(const grant_ref_t * private_head)453 gnttab_empty_grant_references(const grant_ref_t *private_head)
454 {
455 return (*private_head == GNTTAB_LIST_END);
456 }
457
458 int
gnttab_claim_grant_reference(grant_ref_t * private_head)459 gnttab_claim_grant_reference(grant_ref_t *private_head)
460 {
461 grant_ref_t g = *private_head;
462
463 if (g == GNTTAB_LIST_END)
464 return (-1);
465 *private_head = GNTTAB_ENTRY(g);
466 return (g);
467 }
468
469 void
gnttab_release_grant_reference(grant_ref_t * private_head,grant_ref_t release)470 gnttab_release_grant_reference(grant_ref_t *private_head, grant_ref_t release)
471 {
472 ASSERT(VALID_GRANT_REF(release));
473
474 GNTTAB_ENTRY(release) = *private_head;
475 *private_head = release;
476 }
477
478 void
gnttab_request_free_callback(struct gnttab_free_callback * callback,void (* fn)(void *),void * arg,uint16_t count)479 gnttab_request_free_callback(struct gnttab_free_callback *callback,
480 void (*fn)(void *), void *arg, uint16_t count)
481 {
482 mutex_enter(&gnttab_list_lock);
483 if (callback->next)
484 goto out;
485 callback->fn = fn;
486 callback->arg = arg;
487 callback->count = count;
488 callback->next = gnttab_free_callback_list;
489 gnttab_free_callback_list = callback;
490 check_free_callbacks();
491 out:
492 mutex_exit(&gnttab_list_lock);
493 }
494
495 void
gnttab_cancel_free_callback(struct gnttab_free_callback * callback)496 gnttab_cancel_free_callback(struct gnttab_free_callback *callback)
497 {
498 struct gnttab_free_callback **pcb;
499
500 mutex_enter(&gnttab_list_lock);
501 for (pcb = &gnttab_free_callback_list; *pcb; pcb = &(*pcb)->next) {
502 if (*pcb == callback) {
503 *pcb = callback->next;
504 break;
505 }
506 }
507 mutex_exit(&gnttab_list_lock);
508 }
509
510 static gnttab_frame_t *
gnttab_setup(gnttab_setup_table_t * pset)511 gnttab_setup(gnttab_setup_table_t *pset)
512 {
513 gnttab_frame_t *frames;
514
515 frames = kmem_alloc(pset->nr_frames * sizeof (gnttab_frame_t),
516 KM_SLEEP);
517
518 /*LINTED: constant in conditional context*/
519 set_xen_guest_handle(pset->frame_list, frames);
520
521 #ifndef XPV_HVM_DRIVER
522 /*
523 * Take pset->nr_frames pages of grant table space from
524 * the hypervisor and map it
525 */
526 if ((HYPERVISOR_grant_table_op(GNTTABOP_setup_table, pset, 1) != 0) ||
527 (pset->status != 0)) {
528 cmn_err(CE_PANIC, "Grant Table setup failed");
529 }
530 #endif
531
532 return (frames);
533 }
534
535 #ifdef XPV_HVM_DRIVER
536 static void
gnttab_map(void)537 gnttab_map(void)
538 {
539 struct xen_add_to_physmap xatp;
540 caddr_t va;
541 pfn_t pfn;
542 int i;
543
544 va = (caddr_t)shared;
545 for (i = 0; i < max_nr_grant_frames(); i++) {
546 if ((pfn = hat_getpfnum(kas.a_hat, va)) == PFN_INVALID)
547 cmn_err(CE_PANIC, "gnttab_map: Invalid pfn");
548
549 xatp.domid = DOMID_SELF;
550 xatp.idx = i;
551 xatp.space = XENMAPSPACE_grant_table;
552 xatp.gpfn = pfn;
553 hat_unload(kas.a_hat, va, MMU_PAGESIZE, HAT_UNLOAD);
554 /*
555 * This call replaces the existing machine page backing
556 * the given gpfn with the page from the allocated grant
557 * table at index idx. The existing machine page is
558 * returned to the free list.
559 */
560 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp) != 0)
561 panic("Couldn't map grant table");
562 hat_devload(kas.a_hat, va, MMU_PAGESIZE, pfn,
563 PROT_READ | PROT_WRITE | HAT_STORECACHING_OK,
564 HAT_LOAD | HAT_LOAD_LOCK | HAT_LOAD_NOCONSIST);
565 va += MMU_PAGESIZE;
566 }
567 }
568 #endif /* XPV_HVM_DRIVER */
569
570 void
gnttab_init(void)571 gnttab_init(void)
572 {
573 gnttab_setup_table_t set;
574 int i;
575 uint_t nr_init_grefs, max_nr_glist_frames, nr_glist_frames;
576 gnttab_frame_t *frames;
577
578 /*
579 * gnttab_init() should only be invoked once.
580 */
581 mutex_enter(&gnttab_list_lock);
582 ASSERT(nr_grant_frames == 0);
583 nr_grant_frames = 1;
584 mutex_exit(&gnttab_list_lock);
585
586 max_nr_glist_frames = (max_nr_grant_frames() *
587 GREFS_PER_GRANT_FRAME / RPP);
588
589 set.dom = DOMID_SELF;
590 set.nr_frames = max_nr_grant_frames();
591 frames = gnttab_setup(&set);
592
593 #ifdef XPV_HVM_DRIVER
594 shared = (grant_entry_t *)xen_alloc_pages(set.nr_frames);
595
596 gnttab_map();
597 #else /* XPV_HVM_DRIVER */
598 shared = vmem_xalloc(heap_arena, set.nr_frames * MMU_PAGESIZE,
599 MMU_PAGESIZE, 0, 0, 0, 0, VM_SLEEP);
600 for (i = 0; i < set.nr_frames; i++) {
601 hat_devload(kas.a_hat, (caddr_t)GT_PGADDR(i), PAGESIZE,
602 xen_assign_pfn(frames[i]),
603 PROT_READ | PROT_WRITE | HAT_STORECACHING_OK,
604 HAT_LOAD_LOCK);
605 }
606 #endif
607
608 gnttab_list = kmem_alloc(max_nr_glist_frames * sizeof (grant_ref_t *),
609 KM_SLEEP);
610
611 nr_glist_frames = (nr_grant_frames * GREFS_PER_GRANT_FRAME + RPP - 1)
612 / RPP;
613 for (i = 0; i < nr_glist_frames; i++) {
614 gnttab_list[i] = kmem_alloc(PAGESIZE, KM_SLEEP);
615 }
616
617 kmem_free(frames, set.nr_frames * sizeof (gnttab_frame_t));
618
619 nr_init_grefs = nr_grant_frames * GREFS_PER_GRANT_FRAME;
620
621 for (i = NR_RESERVED_ENTRIES; i < nr_init_grefs - 1; i++)
622 GNTTAB_ENTRY(i) = i + 1;
623
624 GNTTAB_ENTRY(nr_init_grefs - 1) = GNTTAB_LIST_END;
625 gnttab_free_count = nr_init_grefs - NR_RESERVED_ENTRIES;
626 gnttab_free_head = NR_RESERVED_ENTRIES;
627 }
628
629 void
gnttab_resume(void)630 gnttab_resume(void)
631 {
632 gnttab_setup_table_t set;
633 int i;
634 gnttab_frame_t *frames;
635 uint_t available_frames = max_nr_grant_frames();
636
637 if (available_frames < nr_grant_frames) {
638 cmn_err(CE_PANIC, "Hypervisor does not have enough grant "
639 "frames: required(%u), available(%u)", nr_grant_frames,
640 available_frames);
641 }
642
643 #ifdef XPV_HVM_DRIVER
644 gnttab_map();
645 #endif /* XPV_HVM_DRIVER */
646
647 set.dom = DOMID_SELF;
648 set.nr_frames = available_frames;
649 frames = gnttab_setup(&set);
650
651 for (i = 0; i < available_frames; i++) {
652 (void) HYPERVISOR_update_va_mapping(GT_PGADDR(i),
653 FRAME_TO_MA(frames[i]) | PT_VALID | PT_WRITABLE,
654 UVMF_INVLPG | UVMF_ALL);
655 }
656 kmem_free(frames, set.nr_frames * sizeof (gnttab_frame_t));
657 }
658
659 void
gnttab_suspend(void)660 gnttab_suspend(void)
661 {
662 int i;
663
664 /*
665 * clear grant table mappings before suspending
666 */
667 for (i = 0; i < max_nr_grant_frames(); i++) {
668 (void) HYPERVISOR_update_va_mapping(GT_PGADDR(i),
669 0, UVMF_INVLPG);
670 }
671 }
672
673 /*
674 * Local variables:
675 * c-file-style: "solaris"
676 * indent-tabs-mode: t
677 * c-indent-level: 8
678 * c-basic-offset: 8
679 * tab-width: 8
680 * End:
681 */
682