xen-gntdev: Fix unmap notify on PV domains
[deliverable/linux.git] / drivers / xen / gntdev.c
CommitLineData
ab31523c
GH
1/******************************************************************************
2 * gntdev.c
3 *
4 * Device for accessing (in user-space) pages that have been granted by other
5 * domains.
6 *
7 * Copyright (c) 2006-2007, D G Murray.
8 * (c) 2009 Gerd Hoffmann <kraxel@redhat.com>
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20#undef DEBUG
21
22#include <linux/module.h>
23#include <linux/kernel.h>
24#include <linux/init.h>
25#include <linux/miscdevice.h>
26#include <linux/fs.h>
27#include <linux/mm.h>
28#include <linux/mman.h>
29#include <linux/mmu_notifier.h>
30#include <linux/types.h>
31#include <linux/uaccess.h>
32#include <linux/sched.h>
33#include <linux/spinlock.h>
34#include <linux/slab.h>
aab8f11a 35#include <linux/highmem.h>
ab31523c
GH
36
37#include <xen/xen.h>
38#include <xen/grant_table.h>
39#include <xen/gntdev.h>
bdc612dc 40#include <xen/events.h>
ab31523c
GH
41#include <asm/xen/hypervisor.h>
42#include <asm/xen/hypercall.h>
43#include <asm/xen/page.h>
44
45MODULE_LICENSE("GPL");
46MODULE_AUTHOR("Derek G. Murray <Derek.Murray@cl.cam.ac.uk>, "
47 "Gerd Hoffmann <kraxel@redhat.com>");
48MODULE_DESCRIPTION("User-space granted page access driver");
49
ef91082e 50static int limit = 1024*1024;
ab31523c 51module_param(limit, int, 0644);
ef91082e
DDG
52MODULE_PARM_DESC(limit, "Maximum number of grants that may be mapped by "
53 "the gntdev device");
54
55static atomic_t pages_mapped = ATOMIC_INIT(0);
ab31523c 56
aab8f11a
DDG
57static int use_ptemod;
58
ab31523c
GH
59struct gntdev_priv {
60 struct list_head maps;
ab31523c
GH
61 /* lock protects maps from concurrent changes */
62 spinlock_t lock;
63 struct mm_struct *mm;
64 struct mmu_notifier mn;
65};
66
bdc612dc
DDG
67struct unmap_notify {
68 int flags;
69 /* Address relative to the start of the grant_map */
70 int addr;
71 int event;
72};
73
ab31523c
GH
74struct grant_map {
75 struct list_head next;
ab31523c
GH
76 struct vm_area_struct *vma;
77 int index;
78 int count;
79 int flags;
80 int is_mapped;
68b025c8 81 atomic_t users;
bdc612dc 82 struct unmap_notify notify;
ab31523c
GH
83 struct ioctl_gntdev_grant_ref *grants;
84 struct gnttab_map_grant_ref *map_ops;
85 struct gnttab_unmap_grant_ref *unmap_ops;
a12b4eb3 86 struct page **pages;
ab31523c
GH
87};
88
aab8f11a
DDG
89static int unmap_grant_pages(struct grant_map *map, int offset, int pages);
90
ab31523c
GH
91/* ------------------------------------------------------------------ */
92
93static void gntdev_print_maps(struct gntdev_priv *priv,
94 char *text, int text_index)
95{
96#ifdef DEBUG
97 struct grant_map *map;
98
ef91082e 99 pr_debug("%s: maps list (priv %p)\n", __func__, priv);
ab31523c
GH
100 list_for_each_entry(map, &priv->maps, next)
101 pr_debug(" index %2d, count %2d %s\n",
102 map->index, map->count,
103 map->index == text_index && text ? text : "");
104#endif
105}
106
107static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count)
108{
109 struct grant_map *add;
a12b4eb3 110 int i;
ab31523c
GH
111
112 add = kzalloc(sizeof(struct grant_map), GFP_KERNEL);
113 if (NULL == add)
114 return NULL;
115
116 add->grants = kzalloc(sizeof(add->grants[0]) * count, GFP_KERNEL);
117 add->map_ops = kzalloc(sizeof(add->map_ops[0]) * count, GFP_KERNEL);
118 add->unmap_ops = kzalloc(sizeof(add->unmap_ops[0]) * count, GFP_KERNEL);
a12b4eb3
SS
119 add->pages = kzalloc(sizeof(add->pages[0]) * count, GFP_KERNEL);
120 if (NULL == add->grants ||
121 NULL == add->map_ops ||
122 NULL == add->unmap_ops ||
123 NULL == add->pages)
ab31523c
GH
124 goto err;
125
a12b4eb3
SS
126 for (i = 0; i < count; i++) {
127 add->pages[i] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
128 if (add->pages[i] == NULL)
129 goto err;
130 }
131
ab31523c
GH
132 add->index = 0;
133 add->count = count;
68b025c8 134 atomic_set(&add->users, 1);
ab31523c 135
ab31523c
GH
136 return add;
137
138err:
a12b4eb3
SS
139 if (add->pages)
140 for (i = 0; i < count; i++) {
141 if (add->pages[i])
142 __free_page(add->pages[i]);
143 }
144 kfree(add->pages);
ab31523c
GH
145 kfree(add->grants);
146 kfree(add->map_ops);
147 kfree(add->unmap_ops);
148 kfree(add);
149 return NULL;
150}
151
152static void gntdev_add_map(struct gntdev_priv *priv, struct grant_map *add)
153{
154 struct grant_map *map;
155
156 list_for_each_entry(map, &priv->maps, next) {
157 if (add->index + add->count < map->index) {
158 list_add_tail(&add->next, &map->next);
159 goto done;
160 }
161 add->index = map->index + map->count;
162 }
163 list_add_tail(&add->next, &priv->maps);
164
165done:
ab31523c
GH
166 gntdev_print_maps(priv, "[new]", add->index);
167}
168
169static struct grant_map *gntdev_find_map_index(struct gntdev_priv *priv,
170 int index, int count)
171{
172 struct grant_map *map;
173
174 list_for_each_entry(map, &priv->maps, next) {
175 if (map->index != index)
176 continue;
bdc612dc 177 if (count && map->count != count)
ab31523c
GH
178 continue;
179 return map;
180 }
181 return NULL;
182}
183
68b025c8 184static void gntdev_put_map(struct grant_map *map)
ab31523c 185{
a12b4eb3
SS
186 int i;
187
ab31523c
GH
188 if (!map)
189 return;
a12b4eb3 190
68b025c8
DDG
191 if (!atomic_dec_and_test(&map->users))
192 return;
193
194 atomic_sub(map->count, &pages_mapped);
195
bdc612dc
DDG
196 if (map->notify.flags & UNMAP_NOTIFY_SEND_EVENT) {
197 notify_remote_via_evtchn(map->notify.event);
198 }
199
aab8f11a
DDG
200 if (map->pages) {
201 if (!use_ptemod)
202 unmap_grant_pages(map, 0, map->count);
203
a12b4eb3 204 for (i = 0; i < map->count; i++) {
aab8f11a
DDG
205 uint32_t check, *tmp;
206 if (!map->pages[i])
207 continue;
208 /* XXX When unmapping in an HVM domain, Xen will
209 * sometimes end up mapping the GFN to an invalid MFN.
210 * In this case, writes will be discarded and reads will
211 * return all 0xFF bytes. Leak these unusable GFNs
212 * until Xen supports fixing their p2m mapping.
213 *
214 * Confirmed present in Xen 4.1-RC3 with HVM source
215 */
216 tmp = kmap(map->pages[i]);
217 *tmp = 0xdeaddead;
218 mb();
219 check = *tmp;
220 kunmap(map->pages[i]);
221 if (check == 0xdeaddead)
a12b4eb3 222 __free_page(map->pages[i]);
aab8f11a
DDG
223 else
224 pr_debug("Discard page %d=%ld\n", i,
225 page_to_pfn(map->pages[i]));
a12b4eb3 226 }
aab8f11a 227 }
a12b4eb3 228 kfree(map->pages);
ab31523c
GH
229 kfree(map->grants);
230 kfree(map->map_ops);
231 kfree(map->unmap_ops);
232 kfree(map);
233}
234
235/* ------------------------------------------------------------------ */
236
237static int find_grant_ptes(pte_t *pte, pgtable_t token,
238 unsigned long addr, void *data)
239{
240 struct grant_map *map = data;
241 unsigned int pgnr = (addr - map->vma->vm_start) >> PAGE_SHIFT;
aab8f11a 242 int flags = map->flags | GNTMAP_application_map | GNTMAP_contains_pte;
ab31523c
GH
243 u64 pte_maddr;
244
245 BUG_ON(pgnr >= map->count);
ba5d1012
JF
246 pte_maddr = arbitrary_virt_to_machine(pte).maddr;
247
aab8f11a 248 gnttab_set_map_op(&map->map_ops[pgnr], pte_maddr, flags,
ab31523c
GH
249 map->grants[pgnr].ref,
250 map->grants[pgnr].domid);
aab8f11a 251 gnttab_set_unmap_op(&map->unmap_ops[pgnr], pte_maddr, flags,
ab31523c
GH
252 0 /* handle */);
253 return 0;
254}
255
256static int map_grant_pages(struct grant_map *map)
257{
258 int i, err = 0;
aab8f11a
DDG
259 phys_addr_t addr;
260
261 if (!use_ptemod) {
262 for (i = 0; i < map->count; i++) {
263 addr = (phys_addr_t)
264 pfn_to_kaddr(page_to_pfn(map->pages[i]));
265 gnttab_set_map_op(&map->map_ops[i], addr, map->flags,
266 map->grants[i].ref,
267 map->grants[i].domid);
268 gnttab_set_unmap_op(&map->unmap_ops[i], addr,
269 map->flags, 0 /* handle */);
270 }
271 }
ab31523c
GH
272
273 pr_debug("map %d+%d\n", map->index, map->count);
a12b4eb3 274 err = gnttab_map_refs(map->map_ops, map->pages, map->count);
ab31523c
GH
275 if (err)
276 return err;
277
278 for (i = 0; i < map->count; i++) {
279 if (map->map_ops[i].status)
280 err = -EINVAL;
281 map->unmap_ops[i].handle = map->map_ops[i].handle;
282 }
283 return err;
284}
285
286static int unmap_grant_pages(struct grant_map *map, int offset, int pages)
287{
288 int i, err = 0;
289
bdc612dc
DDG
290 if (map->notify.flags & UNMAP_NOTIFY_CLEAR_BYTE) {
291 int pgno = (map->notify.addr >> PAGE_SHIFT);
0ea22f07
DDG
292 if (pgno >= offset && pgno < offset + pages && use_ptemod) {
293 void __user *tmp;
294 tmp = map->vma->vm_start + map->notify.addr;
295 copy_to_user(tmp, &err, 1);
296 map->notify.flags &= ~UNMAP_NOTIFY_CLEAR_BYTE;
297 } else if (pgno >= offset && pgno < offset + pages) {
bdc612dc
DDG
298 uint8_t *tmp = kmap(map->pages[pgno]);
299 tmp[map->notify.addr & (PAGE_SIZE-1)] = 0;
300 kunmap(map->pages[pgno]);
301 map->notify.flags &= ~UNMAP_NOTIFY_CLEAR_BYTE;
302 }
303 }
304
ab31523c 305 pr_debug("map %d+%d [%d+%d]\n", map->index, map->count, offset, pages);
0ea22f07 306 err = gnttab_unmap_refs(map->unmap_ops + offset, map->pages + offset, pages);
ab31523c
GH
307 if (err)
308 return err;
309
310 for (i = 0; i < pages; i++) {
311 if (map->unmap_ops[offset+i].status)
312 err = -EINVAL;
313 map->unmap_ops[offset+i].handle = 0;
314 }
315 return err;
316}
317
318/* ------------------------------------------------------------------ */
319
320static void gntdev_vma_close(struct vm_area_struct *vma)
321{
322 struct grant_map *map = vma->vm_private_data;
323
324 pr_debug("close %p\n", vma);
325 map->is_mapped = 0;
326 map->vma = NULL;
327 vma->vm_private_data = NULL;
68b025c8 328 gntdev_put_map(map);
ab31523c
GH
329}
330
ab31523c
GH
331static struct vm_operations_struct gntdev_vmops = {
332 .close = gntdev_vma_close,
ab31523c
GH
333};
334
335/* ------------------------------------------------------------------ */
336
337static void mn_invl_range_start(struct mmu_notifier *mn,
338 struct mm_struct *mm,
339 unsigned long start, unsigned long end)
340{
341 struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn);
342 struct grant_map *map;
343 unsigned long mstart, mend;
344 int err;
345
346 spin_lock(&priv->lock);
347 list_for_each_entry(map, &priv->maps, next) {
348 if (!map->vma)
349 continue;
350 if (!map->is_mapped)
351 continue;
352 if (map->vma->vm_start >= end)
353 continue;
354 if (map->vma->vm_end <= start)
355 continue;
356 mstart = max(start, map->vma->vm_start);
357 mend = min(end, map->vma->vm_end);
358 pr_debug("map %d+%d (%lx %lx), range %lx %lx, mrange %lx %lx\n",
359 map->index, map->count,
360 map->vma->vm_start, map->vma->vm_end,
361 start, end, mstart, mend);
362 err = unmap_grant_pages(map,
363 (mstart - map->vma->vm_start) >> PAGE_SHIFT,
364 (mend - mstart) >> PAGE_SHIFT);
365 WARN_ON(err);
366 }
367 spin_unlock(&priv->lock);
368}
369
370static void mn_invl_page(struct mmu_notifier *mn,
371 struct mm_struct *mm,
372 unsigned long address)
373{
374 mn_invl_range_start(mn, mm, address, address + PAGE_SIZE);
375}
376
377static void mn_release(struct mmu_notifier *mn,
378 struct mm_struct *mm)
379{
380 struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn);
381 struct grant_map *map;
382 int err;
383
384 spin_lock(&priv->lock);
385 list_for_each_entry(map, &priv->maps, next) {
386 if (!map->vma)
387 continue;
388 pr_debug("map %d+%d (%lx %lx)\n",
389 map->index, map->count,
390 map->vma->vm_start, map->vma->vm_end);
391 err = unmap_grant_pages(map, /* offset */ 0, map->count);
392 WARN_ON(err);
393 }
394 spin_unlock(&priv->lock);
395}
396
397struct mmu_notifier_ops gntdev_mmu_ops = {
398 .release = mn_release,
399 .invalidate_page = mn_invl_page,
400 .invalidate_range_start = mn_invl_range_start,
401};
402
403/* ------------------------------------------------------------------ */
404
405static int gntdev_open(struct inode *inode, struct file *flip)
406{
407 struct gntdev_priv *priv;
408 int ret = 0;
409
410 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
411 if (!priv)
412 return -ENOMEM;
413
414 INIT_LIST_HEAD(&priv->maps);
415 spin_lock_init(&priv->lock);
ab31523c 416
aab8f11a
DDG
417 if (use_ptemod) {
418 priv->mm = get_task_mm(current);
419 if (!priv->mm) {
420 kfree(priv);
421 return -ENOMEM;
422 }
423 priv->mn.ops = &gntdev_mmu_ops;
424 ret = mmu_notifier_register(&priv->mn, priv->mm);
425 mmput(priv->mm);
ab31523c 426 }
ab31523c
GH
427
428 if (ret) {
429 kfree(priv);
430 return ret;
431 }
432
433 flip->private_data = priv;
434 pr_debug("priv %p\n", priv);
435
436 return 0;
437}
438
439static int gntdev_release(struct inode *inode, struct file *flip)
440{
441 struct gntdev_priv *priv = flip->private_data;
442 struct grant_map *map;
ab31523c
GH
443
444 pr_debug("priv %p\n", priv);
445
446 spin_lock(&priv->lock);
447 while (!list_empty(&priv->maps)) {
448 map = list_entry(priv->maps.next, struct grant_map, next);
68b025c8
DDG
449 list_del(&map->next);
450 gntdev_put_map(map);
ab31523c
GH
451 }
452 spin_unlock(&priv->lock);
453
aab8f11a
DDG
454 if (use_ptemod)
455 mmu_notifier_unregister(&priv->mn, priv->mm);
ab31523c
GH
456 kfree(priv);
457 return 0;
458}
459
460static long gntdev_ioctl_map_grant_ref(struct gntdev_priv *priv,
461 struct ioctl_gntdev_map_grant_ref __user *u)
462{
463 struct ioctl_gntdev_map_grant_ref op;
464 struct grant_map *map;
465 int err;
466
467 if (copy_from_user(&op, u, sizeof(op)) != 0)
468 return -EFAULT;
469 pr_debug("priv %p, add %d\n", priv, op.count);
470 if (unlikely(op.count <= 0))
471 return -EINVAL;
ab31523c
GH
472
473 err = -ENOMEM;
474 map = gntdev_alloc_map(priv, op.count);
475 if (!map)
476 return err;
ef91082e 477
68b025c8
DDG
478 if (unlikely(atomic_add_return(op.count, &pages_mapped) > limit)) {
479 pr_debug("can't map: over limit\n");
480 gntdev_put_map(map);
ab31523c
GH
481 return err;
482 }
483
68b025c8
DDG
484 if (copy_from_user(map->grants, &u->refs,
485 sizeof(map->grants[0]) * op.count) != 0) {
486 gntdev_put_map(map);
ef91082e
DDG
487 return err;
488 }
489
ab31523c
GH
490 spin_lock(&priv->lock);
491 gntdev_add_map(priv, map);
492 op.index = map->index << PAGE_SHIFT;
493 spin_unlock(&priv->lock);
494
68b025c8
DDG
495 if (copy_to_user(u, &op, sizeof(op)) != 0)
496 return -EFAULT;
497
ab31523c
GH
498 return 0;
499}
500
501static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv,
502 struct ioctl_gntdev_unmap_grant_ref __user *u)
503{
504 struct ioctl_gntdev_unmap_grant_ref op;
505 struct grant_map *map;
506 int err = -ENOENT;
507
508 if (copy_from_user(&op, u, sizeof(op)) != 0)
509 return -EFAULT;
510 pr_debug("priv %p, del %d+%d\n", priv, (int)op.index, (int)op.count);
511
512 spin_lock(&priv->lock);
513 map = gntdev_find_map_index(priv, op.index >> PAGE_SHIFT, op.count);
68b025c8
DDG
514 if (map) {
515 list_del(&map->next);
516 gntdev_put_map(map);
517 err = 0;
518 }
ab31523c 519 spin_unlock(&priv->lock);
ab31523c
GH
520 return err;
521}
522
523static long gntdev_ioctl_get_offset_for_vaddr(struct gntdev_priv *priv,
524 struct ioctl_gntdev_get_offset_for_vaddr __user *u)
525{
526 struct ioctl_gntdev_get_offset_for_vaddr op;
a879211b 527 struct vm_area_struct *vma;
ab31523c
GH
528 struct grant_map *map;
529
530 if (copy_from_user(&op, u, sizeof(op)) != 0)
531 return -EFAULT;
532 pr_debug("priv %p, offset for vaddr %lx\n", priv, (unsigned long)op.vaddr);
533
a879211b
DDG
534 vma = find_vma(current->mm, op.vaddr);
535 if (!vma || vma->vm_ops != &gntdev_vmops)
ab31523c 536 return -EINVAL;
a879211b
DDG
537
538 map = vma->vm_private_data;
539 if (!map)
540 return -EINVAL;
541
ab31523c
GH
542 op.offset = map->index << PAGE_SHIFT;
543 op.count = map->count;
ab31523c
GH
544
545 if (copy_to_user(u, &op, sizeof(op)) != 0)
546 return -EFAULT;
547 return 0;
548}
549
bdc612dc
DDG
550static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u)
551{
552 struct ioctl_gntdev_unmap_notify op;
553 struct grant_map *map;
554 int rc;
555
556 if (copy_from_user(&op, u, sizeof(op)))
557 return -EFAULT;
558
559 if (op.action & ~(UNMAP_NOTIFY_CLEAR_BYTE|UNMAP_NOTIFY_SEND_EVENT))
560 return -EINVAL;
561
562 spin_lock(&priv->lock);
563
564 list_for_each_entry(map, &priv->maps, next) {
565 uint64_t begin = map->index << PAGE_SHIFT;
566 uint64_t end = (map->index + map->count) << PAGE_SHIFT;
567 if (op.index >= begin && op.index < end)
568 goto found;
569 }
570 rc = -ENOENT;
571 goto unlock_out;
572
573 found:
574 map->notify.flags = op.action;
575 map->notify.addr = op.index - (map->index << PAGE_SHIFT);
576 map->notify.event = op.event_channel_port;
577 rc = 0;
578 unlock_out:
579 spin_unlock(&priv->lock);
580 return rc;
581}
582
ab31523c
GH
583static long gntdev_ioctl(struct file *flip,
584 unsigned int cmd, unsigned long arg)
585{
586 struct gntdev_priv *priv = flip->private_data;
587 void __user *ptr = (void __user *)arg;
588
589 switch (cmd) {
590 case IOCTL_GNTDEV_MAP_GRANT_REF:
591 return gntdev_ioctl_map_grant_ref(priv, ptr);
592
593 case IOCTL_GNTDEV_UNMAP_GRANT_REF:
594 return gntdev_ioctl_unmap_grant_ref(priv, ptr);
595
596 case IOCTL_GNTDEV_GET_OFFSET_FOR_VADDR:
597 return gntdev_ioctl_get_offset_for_vaddr(priv, ptr);
598
bdc612dc
DDG
599 case IOCTL_GNTDEV_SET_UNMAP_NOTIFY:
600 return gntdev_ioctl_notify(priv, ptr);
601
ab31523c
GH
602 default:
603 pr_debug("priv %p, unknown cmd %x\n", priv, cmd);
604 return -ENOIOCTLCMD;
605 }
606
607 return 0;
608}
609
610static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
611{
612 struct gntdev_priv *priv = flip->private_data;
613 int index = vma->vm_pgoff;
614 int count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
615 struct grant_map *map;
aab8f11a 616 int i, err = -EINVAL;
ab31523c
GH
617
618 if ((vma->vm_flags & VM_WRITE) && !(vma->vm_flags & VM_SHARED))
619 return -EINVAL;
620
621 pr_debug("map %d+%d at %lx (pgoff %lx)\n",
622 index, count, vma->vm_start, vma->vm_pgoff);
623
624 spin_lock(&priv->lock);
625 map = gntdev_find_map_index(priv, index, count);
626 if (!map)
627 goto unlock_out;
aab8f11a 628 if (use_ptemod && map->vma)
ab31523c 629 goto unlock_out;
aab8f11a 630 if (use_ptemod && priv->mm != vma->vm_mm) {
ab31523c
GH
631 printk(KERN_WARNING "Huh? Other mm?\n");
632 goto unlock_out;
633 }
634
68b025c8
DDG
635 atomic_inc(&map->users);
636
ab31523c
GH
637 vma->vm_ops = &gntdev_vmops;
638
8d3eaea2 639 vma->vm_flags |= VM_RESERVED|VM_DONTCOPY|VM_DONTEXPAND|VM_PFNMAP;
ab31523c
GH
640
641 vma->vm_private_data = map;
ab31523c 642
aab8f11a
DDG
643 if (use_ptemod)
644 map->vma = vma;
645
646 map->flags = GNTMAP_host_map;
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GH
647 if (!(vma->vm_flags & VM_WRITE))
648 map->flags |= GNTMAP_readonly;
649
f0a70c88
DDG
650 spin_unlock(&priv->lock);
651
aab8f11a
DDG
652 if (use_ptemod) {
653 err = apply_to_page_range(vma->vm_mm, vma->vm_start,
654 vma->vm_end - vma->vm_start,
655 find_grant_ptes, map);
656 if (err) {
657 printk(KERN_WARNING "find_grant_ptes() failure.\n");
90b6f305 658 goto out_put_map;
aab8f11a 659 }
ab31523c
GH
660 }
661
662 err = map_grant_pages(map);
90b6f305
DDG
663 if (err)
664 goto out_put_map;
f0a70c88 665
ab31523c
GH
666 map->is_mapped = 1;
667
aab8f11a
DDG
668 if (!use_ptemod) {
669 for (i = 0; i < count; i++) {
670 err = vm_insert_page(vma, vma->vm_start + i*PAGE_SIZE,
671 map->pages[i]);
672 if (err)
90b6f305 673 goto out_put_map;
aab8f11a
DDG
674 }
675 }
676
f0a70c88
DDG
677 return 0;
678
ab31523c
GH
679unlock_out:
680 spin_unlock(&priv->lock);
681 return err;
90b6f305
DDG
682
683out_put_map:
684 gntdev_put_map(map);
685 return err;
ab31523c
GH
686}
687
688static const struct file_operations gntdev_fops = {
689 .owner = THIS_MODULE,
690 .open = gntdev_open,
691 .release = gntdev_release,
692 .mmap = gntdev_mmap,
693 .unlocked_ioctl = gntdev_ioctl
694};
695
696static struct miscdevice gntdev_miscdev = {
697 .minor = MISC_DYNAMIC_MINOR,
698 .name = "xen/gntdev",
699 .fops = &gntdev_fops,
700};
701
702/* ------------------------------------------------------------------ */
703
704static int __init gntdev_init(void)
705{
706 int err;
707
708 if (!xen_domain())
709 return -ENODEV;
710
aab8f11a
DDG
711 use_ptemod = xen_pv_domain();
712
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GH
713 err = misc_register(&gntdev_miscdev);
714 if (err != 0) {
715 printk(KERN_ERR "Could not register gntdev device\n");
716 return err;
717 }
718 return 0;
719}
720
721static void __exit gntdev_exit(void)
722{
723 misc_deregister(&gntdev_miscdev);
724}
725
726module_init(gntdev_init);
727module_exit(gntdev_exit);
728
729/* ------------------------------------------------------------------ */
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