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Commit | Line | Data |
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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> | |
1d314567 | 9 | * (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc. |
ab31523c GH |
10 | * |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
19 | */ | |
20 | ||
21 | #undef DEBUG | |
22 | ||
283c0972 JP |
23 | #define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt |
24 | ||
ee7f5225 | 25 | #include <linux/dma-mapping.h> |
ab31523c GH |
26 | #include <linux/module.h> |
27 | #include <linux/kernel.h> | |
28 | #include <linux/init.h> | |
29 | #include <linux/miscdevice.h> | |
30 | #include <linux/fs.h> | |
ab31523c GH |
31 | #include <linux/uaccess.h> |
32 | #include <linux/sched.h> | |
6e84f315 | 33 | #include <linux/sched/mm.h> |
ab31523c GH |
34 | #include <linux/spinlock.h> |
35 | #include <linux/slab.h> | |
aab8f11a | 36 | #include <linux/highmem.h> |
c5f7c5a9 | 37 | #include <linux/refcount.h> |
ab31523c GH |
38 | |
39 | #include <xen/xen.h> | |
40 | #include <xen/grant_table.h> | |
ca47ceaa | 41 | #include <xen/balloon.h> |
ab31523c | 42 | #include <xen/gntdev.h> |
bdc612dc | 43 | #include <xen/events.h> |
a9fd60e2 | 44 | #include <xen/page.h> |
ab31523c GH |
45 | #include <asm/xen/hypervisor.h> |
46 | #include <asm/xen/hypercall.h> | |
ab31523c | 47 | |
1d314567 | 48 | #include "gntdev-common.h" |
932d6562 OA |
49 | #ifdef CONFIG_XEN_GNTDEV_DMABUF |
50 | #include "gntdev-dmabuf.h" | |
51 | #endif | |
1d314567 | 52 | |
ab31523c GH |
53 | MODULE_LICENSE("GPL"); |
54 | MODULE_AUTHOR("Derek G. Murray <Derek.Murray@cl.cam.ac.uk>, " | |
55 | "Gerd Hoffmann <kraxel@redhat.com>"); | |
56 | MODULE_DESCRIPTION("User-space granted page access driver"); | |
57 | ||
ef91082e | 58 | static int limit = 1024*1024; |
ab31523c | 59 | module_param(limit, int, 0644); |
ef91082e DDG |
60 | MODULE_PARM_DESC(limit, "Maximum number of grants that may be mapped by " |
61 | "the gntdev device"); | |
62 | ||
63 | static atomic_t pages_mapped = ATOMIC_INIT(0); | |
ab31523c | 64 | |
aab8f11a | 65 | static int use_ptemod; |
16a1d022 | 66 | #define populate_freeable_maps use_ptemod |
aab8f11a | 67 | |
1d314567 OA |
68 | static int unmap_grant_pages(struct gntdev_grant_map *map, |
69 | int offset, int pages); | |
aab8f11a | 70 | |
975ef7ff OA |
71 | static struct miscdevice gntdev_miscdev; |
72 | ||
ab31523c GH |
73 | /* ------------------------------------------------------------------ */ |
74 | ||
1d314567 OA |
75 | bool gntdev_account_mapped_pages(int count) |
76 | { | |
77 | return atomic_add_return(count, &pages_mapped) > limit; | |
78 | } | |
79 | ||
ab31523c GH |
80 | static void gntdev_print_maps(struct gntdev_priv *priv, |
81 | char *text, int text_index) | |
82 | { | |
83 | #ifdef DEBUG | |
1d314567 | 84 | struct gntdev_grant_map *map; |
ab31523c | 85 | |
ef91082e | 86 | pr_debug("%s: maps list (priv %p)\n", __func__, priv); |
ab31523c GH |
87 | list_for_each_entry(map, &priv->maps, next) |
88 | pr_debug(" index %2d, count %2d %s\n", | |
89 | map->index, map->count, | |
90 | map->index == text_index && text ? text : ""); | |
91 | #endif | |
92 | } | |
93 | ||
1d314567 | 94 | static void gntdev_free_map(struct gntdev_grant_map *map) |
a67baeb7 DV |
95 | { |
96 | if (map == NULL) | |
97 | return; | |
98 | ||
975ef7ff OA |
99 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC |
100 | if (map->dma_vaddr) { | |
101 | struct gnttab_dma_alloc_args args; | |
102 | ||
103 | args.dev = map->dma_dev; | |
104 | args.coherent = !!(map->dma_flags & GNTDEV_DMA_FLAG_COHERENT); | |
105 | args.nr_pages = map->count; | |
106 | args.pages = map->pages; | |
107 | args.frames = map->frames; | |
108 | args.vaddr = map->dma_vaddr; | |
109 | args.dev_bus_addr = map->dma_bus_addr; | |
110 | ||
111 | gnttab_dma_free_pages(&args); | |
112 | } else | |
113 | #endif | |
a67baeb7 | 114 | if (map->pages) |
ff4b156f | 115 | gnttab_free_pages(map->count, map->pages); |
975ef7ff OA |
116 | |
117 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC | |
118 | kfree(map->frames); | |
119 | #endif | |
a67baeb7 DV |
120 | kfree(map->pages); |
121 | kfree(map->grants); | |
122 | kfree(map->map_ops); | |
123 | kfree(map->unmap_ops); | |
124 | kfree(map->kmap_ops); | |
853d0289 | 125 | kfree(map->kunmap_ops); |
a67baeb7 DV |
126 | kfree(map); |
127 | } | |
128 | ||
1d314567 | 129 | struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count, |
975ef7ff | 130 | int dma_flags) |
ab31523c | 131 | { |
1d314567 | 132 | struct gntdev_grant_map *add; |
a12b4eb3 | 133 | int i; |
ab31523c | 134 | |
1d314567 | 135 | add = kzalloc(sizeof(*add), GFP_KERNEL); |
ab31523c GH |
136 | if (NULL == add) |
137 | return NULL; | |
138 | ||
fc6e0c3b DC |
139 | add->grants = kcalloc(count, sizeof(add->grants[0]), GFP_KERNEL); |
140 | add->map_ops = kcalloc(count, sizeof(add->map_ops[0]), GFP_KERNEL); | |
141 | add->unmap_ops = kcalloc(count, sizeof(add->unmap_ops[0]), GFP_KERNEL); | |
142 | add->kmap_ops = kcalloc(count, sizeof(add->kmap_ops[0]), GFP_KERNEL); | |
853d0289 | 143 | add->kunmap_ops = kcalloc(count, sizeof(add->kunmap_ops[0]), GFP_KERNEL); |
fc6e0c3b | 144 | add->pages = kcalloc(count, sizeof(add->pages[0]), GFP_KERNEL); |
a12b4eb3 SS |
145 | if (NULL == add->grants || |
146 | NULL == add->map_ops || | |
147 | NULL == add->unmap_ops || | |
0930bba6 | 148 | NULL == add->kmap_ops || |
853d0289 | 149 | NULL == add->kunmap_ops || |
a12b4eb3 | 150 | NULL == add->pages) |
ab31523c GH |
151 | goto err; |
152 | ||
975ef7ff OA |
153 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC |
154 | add->dma_flags = dma_flags; | |
155 | ||
156 | /* | |
157 | * Check if this mapping is requested to be backed | |
158 | * by a DMA buffer. | |
159 | */ | |
160 | if (dma_flags & (GNTDEV_DMA_FLAG_WC | GNTDEV_DMA_FLAG_COHERENT)) { | |
161 | struct gnttab_dma_alloc_args args; | |
162 | ||
163 | add->frames = kcalloc(count, sizeof(add->frames[0]), | |
164 | GFP_KERNEL); | |
165 | if (!add->frames) | |
166 | goto err; | |
167 | ||
168 | /* Remember the device, so we can free DMA memory. */ | |
169 | add->dma_dev = priv->dma_dev; | |
170 | ||
171 | args.dev = priv->dma_dev; | |
172 | args.coherent = !!(dma_flags & GNTDEV_DMA_FLAG_COHERENT); | |
173 | args.nr_pages = count; | |
174 | args.pages = add->pages; | |
175 | args.frames = add->frames; | |
176 | ||
177 | if (gnttab_dma_alloc_pages(&args)) | |
178 | goto err; | |
179 | ||
180 | add->dma_vaddr = args.vaddr; | |
181 | add->dma_bus_addr = args.dev_bus_addr; | |
182 | } else | |
183 | #endif | |
ff4b156f | 184 | if (gnttab_alloc_pages(count, add->pages)) |
ca47ceaa DDG |
185 | goto err; |
186 | ||
a12b4eb3 | 187 | for (i = 0; i < count; i++) { |
77c35acb DDG |
188 | add->map_ops[i].handle = -1; |
189 | add->unmap_ops[i].handle = -1; | |
0930bba6 | 190 | add->kmap_ops[i].handle = -1; |
853d0289 | 191 | add->kunmap_ops[i].handle = -1; |
a12b4eb3 SS |
192 | } |
193 | ||
ab31523c GH |
194 | add->index = 0; |
195 | add->count = count; | |
c5f7c5a9 | 196 | refcount_set(&add->users, 1); |
ab31523c | 197 | |
ab31523c GH |
198 | return add; |
199 | ||
200 | err: | |
a67baeb7 | 201 | gntdev_free_map(add); |
ab31523c GH |
202 | return NULL; |
203 | } | |
204 | ||
1d314567 | 205 | void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add) |
ab31523c | 206 | { |
1d314567 | 207 | struct gntdev_grant_map *map; |
ab31523c GH |
208 | |
209 | list_for_each_entry(map, &priv->maps, next) { | |
210 | if (add->index + add->count < map->index) { | |
211 | list_add_tail(&add->next, &map->next); | |
212 | goto done; | |
213 | } | |
214 | add->index = map->index + map->count; | |
215 | } | |
216 | list_add_tail(&add->next, &priv->maps); | |
217 | ||
218 | done: | |
ab31523c GH |
219 | gntdev_print_maps(priv, "[new]", add->index); |
220 | } | |
221 | ||
1d314567 OA |
222 | static struct gntdev_grant_map *gntdev_find_map_index(struct gntdev_priv *priv, |
223 | int index, int count) | |
ab31523c | 224 | { |
1d314567 | 225 | struct gntdev_grant_map *map; |
ab31523c GH |
226 | |
227 | list_for_each_entry(map, &priv->maps, next) { | |
228 | if (map->index != index) | |
229 | continue; | |
bdc612dc | 230 | if (count && map->count != count) |
ab31523c GH |
231 | continue; |
232 | return map; | |
233 | } | |
234 | return NULL; | |
235 | } | |
236 | ||
1d314567 | 237 | void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map) |
ab31523c GH |
238 | { |
239 | if (!map) | |
240 | return; | |
a12b4eb3 | 241 | |
c5f7c5a9 | 242 | if (!refcount_dec_and_test(&map->users)) |
68b025c8 DDG |
243 | return; |
244 | ||
245 | atomic_sub(map->count, &pages_mapped); | |
246 | ||
0cc678f8 | 247 | if (map->notify.flags & UNMAP_NOTIFY_SEND_EVENT) { |
bdc612dc | 248 | notify_remote_via_evtchn(map->notify.event); |
0cc678f8 DDG |
249 | evtchn_put(map->notify.event); |
250 | } | |
bdc612dc | 251 | |
16a1d022 | 252 | if (populate_freeable_maps && priv) { |
1401c00e | 253 | mutex_lock(&priv->lock); |
16a1d022 | 254 | list_del(&map->next); |
1401c00e | 255 | mutex_unlock(&priv->lock); |
16a1d022 DDG |
256 | } |
257 | ||
a67baeb7 DV |
258 | if (map->pages && !use_ptemod) |
259 | unmap_grant_pages(map, 0, map->count); | |
260 | gntdev_free_map(map); | |
ab31523c GH |
261 | } |
262 | ||
263 | /* ------------------------------------------------------------------ */ | |
264 | ||
8b1e0f81 | 265 | static int find_grant_ptes(pte_t *pte, unsigned long addr, void *data) |
ab31523c | 266 | { |
1d314567 | 267 | struct gntdev_grant_map *map = data; |
ab31523c | 268 | unsigned int pgnr = (addr - map->vma->vm_start) >> PAGE_SHIFT; |
aab8f11a | 269 | int flags = map->flags | GNTMAP_application_map | GNTMAP_contains_pte; |
ab31523c GH |
270 | u64 pte_maddr; |
271 | ||
272 | BUG_ON(pgnr >= map->count); | |
ba5d1012 JF |
273 | pte_maddr = arbitrary_virt_to_machine(pte).maddr; |
274 | ||
923b2919 DV |
275 | /* |
276 | * Set the PTE as special to force get_user_pages_fast() fall | |
277 | * back to the slow path. If this is not supported as part of | |
278 | * the grant map, it will be done afterwards. | |
279 | */ | |
280 | if (xen_feature(XENFEAT_gnttab_map_avail_bits)) | |
281 | flags |= (1 << _GNTMAP_guest_avail0); | |
282 | ||
aab8f11a | 283 | gnttab_set_map_op(&map->map_ops[pgnr], pte_maddr, flags, |
ab31523c GH |
284 | map->grants[pgnr].ref, |
285 | map->grants[pgnr].domid); | |
aab8f11a | 286 | gnttab_set_unmap_op(&map->unmap_ops[pgnr], pte_maddr, flags, |
77c35acb | 287 | -1 /* handle */); |
ab31523c GH |
288 | return 0; |
289 | } | |
290 | ||
923b2919 | 291 | #ifdef CONFIG_X86 |
8b1e0f81 | 292 | static int set_grant_ptes_as_special(pte_t *pte, unsigned long addr, void *data) |
923b2919 DV |
293 | { |
294 | set_pte_at(current->mm, addr, pte, pte_mkspecial(*pte)); | |
295 | return 0; | |
296 | } | |
297 | #endif | |
298 | ||
1d314567 | 299 | int gntdev_map_grant_pages(struct gntdev_grant_map *map) |
ab31523c GH |
300 | { |
301 | int i, err = 0; | |
aab8f11a DDG |
302 | |
303 | if (!use_ptemod) { | |
12996fc3 | 304 | /* Note: it could already be mapped */ |
77c35acb | 305 | if (map->map_ops[0].handle != -1) |
12996fc3 | 306 | return 0; |
aab8f11a | 307 | for (i = 0; i < map->count; i++) { |
38eaeb0f | 308 | unsigned long addr = (unsigned long) |
aab8f11a DDG |
309 | pfn_to_kaddr(page_to_pfn(map->pages[i])); |
310 | gnttab_set_map_op(&map->map_ops[i], addr, map->flags, | |
311 | map->grants[i].ref, | |
312 | map->grants[i].domid); | |
313 | gnttab_set_unmap_op(&map->unmap_ops[i], addr, | |
77c35acb | 314 | map->flags, -1 /* handle */); |
aab8f11a | 315 | } |
0930bba6 SS |
316 | } else { |
317 | /* | |
318 | * Setup the map_ops corresponding to the pte entries pointing | |
319 | * to the kernel linear addresses of the struct pages. | |
320 | * These ptes are completely different from the user ptes dealt | |
321 | * with find_grant_ptes. | |
322 | */ | |
323 | for (i = 0; i < map->count; i++) { | |
0930bba6 SS |
324 | unsigned long address = (unsigned long) |
325 | pfn_to_kaddr(page_to_pfn(map->pages[i])); | |
0930bba6 SS |
326 | BUG_ON(PageHighMem(map->pages[i])); |
327 | ||
ee072640 SS |
328 | gnttab_set_map_op(&map->kmap_ops[i], address, |
329 | map->flags | GNTMAP_host_map, | |
0930bba6 SS |
330 | map->grants[i].ref, |
331 | map->grants[i].domid); | |
853d0289 DV |
332 | gnttab_set_unmap_op(&map->kunmap_ops[i], address, |
333 | map->flags | GNTMAP_host_map, -1); | |
0930bba6 | 334 | } |
aab8f11a | 335 | } |
ab31523c GH |
336 | |
337 | pr_debug("map %d+%d\n", map->index, map->count); | |
e85fc980 KRW |
338 | err = gnttab_map_refs(map->map_ops, use_ptemod ? map->kmap_ops : NULL, |
339 | map->pages, map->count); | |
ab31523c GH |
340 | if (err) |
341 | return err; | |
342 | ||
343 | for (i = 0; i < map->count; i++) { | |
853d0289 | 344 | if (map->map_ops[i].status) { |
ab31523c | 345 | err = -EINVAL; |
853d0289 | 346 | continue; |
77c35acb | 347 | } |
853d0289 DV |
348 | |
349 | map->unmap_ops[i].handle = map->map_ops[i].handle; | |
350 | if (use_ptemod) | |
351 | map->kunmap_ops[i].handle = map->kmap_ops[i].handle; | |
975ef7ff OA |
352 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC |
353 | else if (map->dma_vaddr) { | |
354 | unsigned long bfn; | |
355 | ||
356 | bfn = pfn_to_bfn(page_to_pfn(map->pages[i])); | |
357 | map->unmap_ops[i].dev_bus_addr = __pfn_to_phys(bfn); | |
358 | } | |
359 | #endif | |
ab31523c GH |
360 | } |
361 | return err; | |
362 | } | |
363 | ||
1d314567 OA |
364 | static int __unmap_grant_pages(struct gntdev_grant_map *map, int offset, |
365 | int pages) | |
ab31523c GH |
366 | { |
367 | int i, err = 0; | |
74528225 | 368 | struct gntab_unmap_queue_data unmap_data; |
ab31523c | 369 | |
bdc612dc DDG |
370 | if (map->notify.flags & UNMAP_NOTIFY_CLEAR_BYTE) { |
371 | int pgno = (map->notify.addr >> PAGE_SHIFT); | |
1affa98d DDG |
372 | if (pgno >= offset && pgno < offset + pages) { |
373 | /* No need for kmap, pages are in lowmem */ | |
374 | uint8_t *tmp = pfn_to_kaddr(page_to_pfn(map->pages[pgno])); | |
bdc612dc | 375 | tmp[map->notify.addr & (PAGE_SIZE-1)] = 0; |
bdc612dc DDG |
376 | map->notify.flags &= ~UNMAP_NOTIFY_CLEAR_BYTE; |
377 | } | |
378 | } | |
379 | ||
74528225 JH |
380 | unmap_data.unmap_ops = map->unmap_ops + offset; |
381 | unmap_data.kunmap_ops = use_ptemod ? map->kunmap_ops + offset : NULL; | |
382 | unmap_data.pages = map->pages + offset; | |
383 | unmap_data.count = pages; | |
384 | ||
b44166cd BL |
385 | err = gnttab_unmap_refs_sync(&unmap_data); |
386 | if (err) | |
387 | return err; | |
ab31523c GH |
388 | |
389 | for (i = 0; i < pages; i++) { | |
390 | if (map->unmap_ops[offset+i].status) | |
391 | err = -EINVAL; | |
77c35acb DDG |
392 | pr_debug("unmap handle=%d st=%d\n", |
393 | map->unmap_ops[offset+i].handle, | |
394 | map->unmap_ops[offset+i].status); | |
395 | map->unmap_ops[offset+i].handle = -1; | |
ab31523c GH |
396 | } |
397 | return err; | |
398 | } | |
399 | ||
1d314567 OA |
400 | static int unmap_grant_pages(struct gntdev_grant_map *map, int offset, |
401 | int pages) | |
b57c1869 DDG |
402 | { |
403 | int range, err = 0; | |
404 | ||
405 | pr_debug("unmap %d+%d [%d+%d]\n", map->index, map->count, offset, pages); | |
406 | ||
407 | /* It is possible the requested range will have a "hole" where we | |
408 | * already unmapped some of the grants. Only unmap valid ranges. | |
409 | */ | |
410 | while (pages && !err) { | |
77c35acb | 411 | while (pages && map->unmap_ops[offset].handle == -1) { |
b57c1869 DDG |
412 | offset++; |
413 | pages--; | |
414 | } | |
415 | range = 0; | |
416 | while (range < pages) { | |
951a0102 | 417 | if (map->unmap_ops[offset+range].handle == -1) |
b57c1869 | 418 | break; |
b57c1869 DDG |
419 | range++; |
420 | } | |
421 | err = __unmap_grant_pages(map, offset, range); | |
422 | offset += range; | |
423 | pages -= range; | |
424 | } | |
425 | ||
426 | return err; | |
427 | } | |
428 | ||
ab31523c GH |
429 | /* ------------------------------------------------------------------ */ |
430 | ||
d79647ae DDG |
431 | static void gntdev_vma_open(struct vm_area_struct *vma) |
432 | { | |
1d314567 | 433 | struct gntdev_grant_map *map = vma->vm_private_data; |
d79647ae DDG |
434 | |
435 | pr_debug("gntdev_vma_open %p\n", vma); | |
c5f7c5a9 | 436 | refcount_inc(&map->users); |
d79647ae DDG |
437 | } |
438 | ||
ab31523c GH |
439 | static void gntdev_vma_close(struct vm_area_struct *vma) |
440 | { | |
1d314567 | 441 | struct gntdev_grant_map *map = vma->vm_private_data; |
16a1d022 DDG |
442 | struct file *file = vma->vm_file; |
443 | struct gntdev_priv *priv = file->private_data; | |
ab31523c | 444 | |
d79647ae | 445 | pr_debug("gntdev_vma_close %p\n", vma); |
2512f298 | 446 | if (use_ptemod) { |
2512f298 DDG |
447 | /* It is possible that an mmu notifier could be running |
448 | * concurrently, so take priv->lock to ensure that the vma won't | |
449 | * vanishing during the unmap_grant_pages call, since we will | |
450 | * spin here until that completes. Such a concurrent call will | |
451 | * not do any unmapping, since that has been done prior to | |
452 | * closing the vma, but it may still iterate the unmap_ops list. | |
453 | */ | |
1401c00e | 454 | mutex_lock(&priv->lock); |
2512f298 | 455 | map->vma = NULL; |
1401c00e | 456 | mutex_unlock(&priv->lock); |
2512f298 | 457 | } |
ab31523c | 458 | vma->vm_private_data = NULL; |
16a1d022 | 459 | gntdev_put_map(priv, map); |
ab31523c GH |
460 | } |
461 | ||
dab069c6 DV |
462 | static struct page *gntdev_vma_find_special_page(struct vm_area_struct *vma, |
463 | unsigned long addr) | |
464 | { | |
1d314567 | 465 | struct gntdev_grant_map *map = vma->vm_private_data; |
dab069c6 DV |
466 | |
467 | return map->pages[(addr - map->pages_vm_start) >> PAGE_SHIFT]; | |
468 | } | |
469 | ||
7cbea8dc | 470 | static const struct vm_operations_struct gntdev_vmops = { |
d79647ae | 471 | .open = gntdev_vma_open, |
ab31523c | 472 | .close = gntdev_vma_close, |
dab069c6 | 473 | .find_special_page = gntdev_vma_find_special_page, |
ab31523c GH |
474 | }; |
475 | ||
476 | /* ------------------------------------------------------------------ */ | |
477 | ||
93065ac7 MH |
478 | static bool in_range(struct gntdev_grant_map *map, |
479 | unsigned long start, unsigned long end) | |
480 | { | |
481 | if (!map->vma) | |
482 | return false; | |
483 | if (map->vma->vm_start >= end) | |
484 | return false; | |
485 | if (map->vma->vm_end <= start) | |
486 | return false; | |
487 | ||
488 | return true; | |
489 | } | |
490 | ||
58a57569 MH |
491 | static int unmap_if_in_range(struct gntdev_grant_map *map, |
492 | unsigned long start, unsigned long end, | |
493 | bool blockable) | |
16a1d022 DDG |
494 | { |
495 | unsigned long mstart, mend; | |
496 | int err; | |
497 | ||
58a57569 MH |
498 | if (!in_range(map, start, end)) |
499 | return 0; | |
500 | ||
501 | if (!blockable) | |
502 | return -EAGAIN; | |
503 | ||
16a1d022 DDG |
504 | mstart = max(start, map->vma->vm_start); |
505 | mend = min(end, map->vma->vm_end); | |
506 | pr_debug("map %d+%d (%lx %lx), range %lx %lx, mrange %lx %lx\n", | |
507 | map->index, map->count, | |
508 | map->vma->vm_start, map->vma->vm_end, | |
509 | start, end, mstart, mend); | |
510 | err = unmap_grant_pages(map, | |
511 | (mstart - map->vma->vm_start) >> PAGE_SHIFT, | |
512 | (mend - mstart) >> PAGE_SHIFT); | |
513 | WARN_ON(err); | |
58a57569 MH |
514 | |
515 | return 0; | |
16a1d022 DDG |
516 | } |
517 | ||
93065ac7 | 518 | static int mn_invl_range_start(struct mmu_notifier *mn, |
5d6527a7 | 519 | const struct mmu_notifier_range *range) |
ab31523c GH |
520 | { |
521 | struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn); | |
1d314567 | 522 | struct gntdev_grant_map *map; |
93065ac7 MH |
523 | int ret = 0; |
524 | ||
dfcd6660 | 525 | if (mmu_notifier_range_blockable(range)) |
93065ac7 MH |
526 | mutex_lock(&priv->lock); |
527 | else if (!mutex_trylock(&priv->lock)) | |
528 | return -EAGAIN; | |
ab31523c | 529 | |
ab31523c | 530 | list_for_each_entry(map, &priv->maps, next) { |
5d6527a7 | 531 | ret = unmap_if_in_range(map, range->start, range->end, |
dfcd6660 | 532 | mmu_notifier_range_blockable(range)); |
58a57569 | 533 | if (ret) |
93065ac7 | 534 | goto out_unlock; |
16a1d022 DDG |
535 | } |
536 | list_for_each_entry(map, &priv->freeable_maps, next) { | |
5d6527a7 | 537 | ret = unmap_if_in_range(map, range->start, range->end, |
dfcd6660 | 538 | mmu_notifier_range_blockable(range)); |
58a57569 | 539 | if (ret) |
93065ac7 | 540 | goto out_unlock; |
ab31523c | 541 | } |
93065ac7 MH |
542 | |
543 | out_unlock: | |
1401c00e | 544 | mutex_unlock(&priv->lock); |
93065ac7 MH |
545 | |
546 | return ret; | |
ab31523c GH |
547 | } |
548 | ||
ab31523c GH |
549 | static void mn_release(struct mmu_notifier *mn, |
550 | struct mm_struct *mm) | |
551 | { | |
552 | struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn); | |
1d314567 | 553 | struct gntdev_grant_map *map; |
ab31523c GH |
554 | int err; |
555 | ||
1401c00e | 556 | mutex_lock(&priv->lock); |
ab31523c GH |
557 | list_for_each_entry(map, &priv->maps, next) { |
558 | if (!map->vma) | |
559 | continue; | |
560 | pr_debug("map %d+%d (%lx %lx)\n", | |
561 | map->index, map->count, | |
562 | map->vma->vm_start, map->vma->vm_end); | |
563 | err = unmap_grant_pages(map, /* offset */ 0, map->count); | |
564 | WARN_ON(err); | |
565 | } | |
16a1d022 DDG |
566 | list_for_each_entry(map, &priv->freeable_maps, next) { |
567 | if (!map->vma) | |
568 | continue; | |
569 | pr_debug("map %d+%d (%lx %lx)\n", | |
570 | map->index, map->count, | |
571 | map->vma->vm_start, map->vma->vm_end); | |
572 | err = unmap_grant_pages(map, /* offset */ 0, map->count); | |
573 | WARN_ON(err); | |
574 | } | |
1401c00e | 575 | mutex_unlock(&priv->lock); |
ab31523c GH |
576 | } |
577 | ||
b9c0a92a | 578 | static const struct mmu_notifier_ops gntdev_mmu_ops = { |
ab31523c | 579 | .release = mn_release, |
ab31523c GH |
580 | .invalidate_range_start = mn_invl_range_start, |
581 | }; | |
582 | ||
583 | /* ------------------------------------------------------------------ */ | |
584 | ||
585 | static int gntdev_open(struct inode *inode, struct file *flip) | |
586 | { | |
587 | struct gntdev_priv *priv; | |
588 | int ret = 0; | |
589 | ||
590 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); | |
591 | if (!priv) | |
592 | return -ENOMEM; | |
593 | ||
594 | INIT_LIST_HEAD(&priv->maps); | |
16a1d022 | 595 | INIT_LIST_HEAD(&priv->freeable_maps); |
1401c00e | 596 | mutex_init(&priv->lock); |
ab31523c | 597 | |
932d6562 | 598 | #ifdef CONFIG_XEN_GNTDEV_DMABUF |
fa13e665 | 599 | priv->dmabuf_priv = gntdev_dmabuf_init(flip); |
932d6562 OA |
600 | if (IS_ERR(priv->dmabuf_priv)) { |
601 | ret = PTR_ERR(priv->dmabuf_priv); | |
602 | kfree(priv); | |
603 | return ret; | |
604 | } | |
605 | #endif | |
606 | ||
aab8f11a DDG |
607 | if (use_ptemod) { |
608 | priv->mm = get_task_mm(current); | |
609 | if (!priv->mm) { | |
610 | kfree(priv); | |
611 | return -ENOMEM; | |
612 | } | |
613 | priv->mn.ops = &gntdev_mmu_ops; | |
614 | ret = mmu_notifier_register(&priv->mn, priv->mm); | |
615 | mmput(priv->mm); | |
ab31523c | 616 | } |
ab31523c GH |
617 | |
618 | if (ret) { | |
619 | kfree(priv); | |
620 | return ret; | |
621 | } | |
622 | ||
623 | flip->private_data = priv; | |
975ef7ff OA |
624 | #ifdef CONFIG_XEN_GRANT_DMA_ALLOC |
625 | priv->dma_dev = gntdev_miscdev.this_device; | |
ee7f5225 | 626 | dma_coerce_mask_and_coherent(priv->dma_dev, DMA_BIT_MASK(64)); |
975ef7ff | 627 | #endif |
ab31523c GH |
628 | pr_debug("priv %p\n", priv); |
629 | ||
630 | return 0; | |
631 | } | |
632 | ||
633 | static int gntdev_release(struct inode *inode, struct file *flip) | |
634 | { | |
635 | struct gntdev_priv *priv = flip->private_data; | |
1d314567 | 636 | struct gntdev_grant_map *map; |
ab31523c GH |
637 | |
638 | pr_debug("priv %p\n", priv); | |
639 | ||
30b03d05 | 640 | mutex_lock(&priv->lock); |
ab31523c | 641 | while (!list_empty(&priv->maps)) { |
1d314567 OA |
642 | map = list_entry(priv->maps.next, |
643 | struct gntdev_grant_map, next); | |
68b025c8 | 644 | list_del(&map->next); |
16a1d022 | 645 | gntdev_put_map(NULL /* already removed */, map); |
ab31523c | 646 | } |
16a1d022 | 647 | WARN_ON(!list_empty(&priv->freeable_maps)); |
30b03d05 | 648 | mutex_unlock(&priv->lock); |
ab31523c | 649 | |
932d6562 OA |
650 | #ifdef CONFIG_XEN_GNTDEV_DMABUF |
651 | gntdev_dmabuf_fini(priv->dmabuf_priv); | |
652 | #endif | |
653 | ||
aab8f11a DDG |
654 | if (use_ptemod) |
655 | mmu_notifier_unregister(&priv->mn, priv->mm); | |
932d6562 | 656 | |
ab31523c GH |
657 | kfree(priv); |
658 | return 0; | |
659 | } | |
660 | ||
661 | static long gntdev_ioctl_map_grant_ref(struct gntdev_priv *priv, | |
662 | struct ioctl_gntdev_map_grant_ref __user *u) | |
663 | { | |
664 | struct ioctl_gntdev_map_grant_ref op; | |
1d314567 | 665 | struct gntdev_grant_map *map; |
ab31523c GH |
666 | int err; |
667 | ||
668 | if (copy_from_user(&op, u, sizeof(op)) != 0) | |
669 | return -EFAULT; | |
670 | pr_debug("priv %p, add %d\n", priv, op.count); | |
671 | if (unlikely(op.count <= 0)) | |
672 | return -EINVAL; | |
ab31523c GH |
673 | |
674 | err = -ENOMEM; | |
975ef7ff | 675 | map = gntdev_alloc_map(priv, op.count, 0 /* This is not a dma-buf. */); |
ab31523c GH |
676 | if (!map) |
677 | return err; | |
ef91082e | 678 | |
1d314567 | 679 | if (unlikely(gntdev_account_mapped_pages(op.count))) { |
68b025c8 | 680 | pr_debug("can't map: over limit\n"); |
16a1d022 | 681 | gntdev_put_map(NULL, map); |
ab31523c GH |
682 | return err; |
683 | } | |
684 | ||
68b025c8 DDG |
685 | if (copy_from_user(map->grants, &u->refs, |
686 | sizeof(map->grants[0]) * op.count) != 0) { | |
16a1d022 DDG |
687 | gntdev_put_map(NULL, map); |
688 | return -EFAULT; | |
ef91082e DDG |
689 | } |
690 | ||
1401c00e | 691 | mutex_lock(&priv->lock); |
ab31523c GH |
692 | gntdev_add_map(priv, map); |
693 | op.index = map->index << PAGE_SHIFT; | |
1401c00e | 694 | mutex_unlock(&priv->lock); |
ab31523c | 695 | |
68b025c8 DDG |
696 | if (copy_to_user(u, &op, sizeof(op)) != 0) |
697 | return -EFAULT; | |
698 | ||
ab31523c GH |
699 | return 0; |
700 | } | |
701 | ||
702 | static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv, | |
703 | struct ioctl_gntdev_unmap_grant_ref __user *u) | |
704 | { | |
705 | struct ioctl_gntdev_unmap_grant_ref op; | |
1d314567 | 706 | struct gntdev_grant_map *map; |
ab31523c GH |
707 | int err = -ENOENT; |
708 | ||
709 | if (copy_from_user(&op, u, sizeof(op)) != 0) | |
710 | return -EFAULT; | |
711 | pr_debug("priv %p, del %d+%d\n", priv, (int)op.index, (int)op.count); | |
712 | ||
1401c00e | 713 | mutex_lock(&priv->lock); |
ab31523c | 714 | map = gntdev_find_map_index(priv, op.index >> PAGE_SHIFT, op.count); |
68b025c8 DDG |
715 | if (map) { |
716 | list_del(&map->next); | |
16a1d022 DDG |
717 | if (populate_freeable_maps) |
718 | list_add_tail(&map->next, &priv->freeable_maps); | |
68b025c8 DDG |
719 | err = 0; |
720 | } | |
1401c00e | 721 | mutex_unlock(&priv->lock); |
1f1503ba | 722 | if (map) |
16a1d022 | 723 | gntdev_put_map(priv, map); |
ab31523c GH |
724 | return err; |
725 | } | |
726 | ||
727 | static long gntdev_ioctl_get_offset_for_vaddr(struct gntdev_priv *priv, | |
728 | struct ioctl_gntdev_get_offset_for_vaddr __user *u) | |
729 | { | |
730 | struct ioctl_gntdev_get_offset_for_vaddr op; | |
a879211b | 731 | struct vm_area_struct *vma; |
1d314567 | 732 | struct gntdev_grant_map *map; |
2512f298 | 733 | int rv = -EINVAL; |
ab31523c GH |
734 | |
735 | if (copy_from_user(&op, u, sizeof(op)) != 0) | |
736 | return -EFAULT; | |
737 | pr_debug("priv %p, offset for vaddr %lx\n", priv, (unsigned long)op.vaddr); | |
738 | ||
2512f298 | 739 | down_read(¤t->mm->mmap_sem); |
a879211b DDG |
740 | vma = find_vma(current->mm, op.vaddr); |
741 | if (!vma || vma->vm_ops != &gntdev_vmops) | |
2512f298 | 742 | goto out_unlock; |
a879211b DDG |
743 | |
744 | map = vma->vm_private_data; | |
745 | if (!map) | |
2512f298 | 746 | goto out_unlock; |
a879211b | 747 | |
ab31523c GH |
748 | op.offset = map->index << PAGE_SHIFT; |
749 | op.count = map->count; | |
2512f298 | 750 | rv = 0; |
ab31523c | 751 | |
2512f298 DDG |
752 | out_unlock: |
753 | up_read(¤t->mm->mmap_sem); | |
754 | ||
755 | if (rv == 0 && copy_to_user(u, &op, sizeof(op)) != 0) | |
ab31523c | 756 | return -EFAULT; |
2512f298 | 757 | return rv; |
ab31523c GH |
758 | } |
759 | ||
bdc612dc DDG |
760 | static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u) |
761 | { | |
762 | struct ioctl_gntdev_unmap_notify op; | |
1d314567 | 763 | struct gntdev_grant_map *map; |
bdc612dc | 764 | int rc; |
0cc678f8 DDG |
765 | int out_flags; |
766 | unsigned int out_event; | |
bdc612dc DDG |
767 | |
768 | if (copy_from_user(&op, u, sizeof(op))) | |
769 | return -EFAULT; | |
770 | ||
771 | if (op.action & ~(UNMAP_NOTIFY_CLEAR_BYTE|UNMAP_NOTIFY_SEND_EVENT)) | |
772 | return -EINVAL; | |
773 | ||
0cc678f8 DDG |
774 | /* We need to grab a reference to the event channel we are going to use |
775 | * to send the notify before releasing the reference we may already have | |
776 | * (if someone has called this ioctl twice). This is required so that | |
777 | * it is possible to change the clear_byte part of the notification | |
778 | * without disturbing the event channel part, which may now be the last | |
779 | * reference to that event channel. | |
780 | */ | |
781 | if (op.action & UNMAP_NOTIFY_SEND_EVENT) { | |
782 | if (evtchn_get(op.event_channel_port)) | |
783 | return -EINVAL; | |
784 | } | |
785 | ||
786 | out_flags = op.action; | |
787 | out_event = op.event_channel_port; | |
788 | ||
1401c00e | 789 | mutex_lock(&priv->lock); |
bdc612dc DDG |
790 | |
791 | list_for_each_entry(map, &priv->maps, next) { | |
792 | uint64_t begin = map->index << PAGE_SHIFT; | |
793 | uint64_t end = (map->index + map->count) << PAGE_SHIFT; | |
794 | if (op.index >= begin && op.index < end) | |
795 | goto found; | |
796 | } | |
797 | rc = -ENOENT; | |
798 | goto unlock_out; | |
799 | ||
800 | found: | |
9960be97 DDG |
801 | if ((op.action & UNMAP_NOTIFY_CLEAR_BYTE) && |
802 | (map->flags & GNTMAP_readonly)) { | |
803 | rc = -EINVAL; | |
804 | goto unlock_out; | |
805 | } | |
806 | ||
0cc678f8 DDG |
807 | out_flags = map->notify.flags; |
808 | out_event = map->notify.event; | |
809 | ||
bdc612dc DDG |
810 | map->notify.flags = op.action; |
811 | map->notify.addr = op.index - (map->index << PAGE_SHIFT); | |
812 | map->notify.event = op.event_channel_port; | |
0cc678f8 | 813 | |
bdc612dc | 814 | rc = 0; |
0cc678f8 | 815 | |
bdc612dc | 816 | unlock_out: |
1401c00e | 817 | mutex_unlock(&priv->lock); |
0cc678f8 DDG |
818 | |
819 | /* Drop the reference to the event channel we did not save in the map */ | |
820 | if (out_flags & UNMAP_NOTIFY_SEND_EVENT) | |
821 | evtchn_put(out_event); | |
822 | ||
bdc612dc DDG |
823 | return rc; |
824 | } | |
825 | ||
36ae220a | 826 | #define GNTDEV_COPY_BATCH 16 |
a4cdb556 DV |
827 | |
828 | struct gntdev_copy_batch { | |
829 | struct gnttab_copy ops[GNTDEV_COPY_BATCH]; | |
830 | struct page *pages[GNTDEV_COPY_BATCH]; | |
831 | s16 __user *status[GNTDEV_COPY_BATCH]; | |
832 | unsigned int nr_ops; | |
833 | unsigned int nr_pages; | |
834 | }; | |
835 | ||
836 | static int gntdev_get_page(struct gntdev_copy_batch *batch, void __user *virt, | |
837 | bool writeable, unsigned long *gfn) | |
838 | { | |
839 | unsigned long addr = (unsigned long)virt; | |
840 | struct page *page; | |
841 | unsigned long xen_pfn; | |
842 | int ret; | |
843 | ||
73b0140b | 844 | ret = get_user_pages_fast(addr, 1, writeable ? FOLL_WRITE : 0, &page); |
a4cdb556 DV |
845 | if (ret < 0) |
846 | return ret; | |
847 | ||
848 | batch->pages[batch->nr_pages++] = page; | |
849 | ||
850 | xen_pfn = page_to_xen_pfn(page) + XEN_PFN_DOWN(addr & ~PAGE_MASK); | |
851 | *gfn = pfn_to_gfn(xen_pfn); | |
852 | ||
853 | return 0; | |
854 | } | |
855 | ||
856 | static void gntdev_put_pages(struct gntdev_copy_batch *batch) | |
857 | { | |
858 | unsigned int i; | |
859 | ||
860 | for (i = 0; i < batch->nr_pages; i++) | |
861 | put_page(batch->pages[i]); | |
862 | batch->nr_pages = 0; | |
863 | } | |
864 | ||
865 | static int gntdev_copy(struct gntdev_copy_batch *batch) | |
866 | { | |
867 | unsigned int i; | |
868 | ||
869 | gnttab_batch_copy(batch->ops, batch->nr_ops); | |
870 | gntdev_put_pages(batch); | |
871 | ||
872 | /* | |
873 | * For each completed op, update the status if the op failed | |
874 | * and all previous ops for the segment were successful. | |
875 | */ | |
876 | for (i = 0; i < batch->nr_ops; i++) { | |
877 | s16 status = batch->ops[i].status; | |
878 | s16 old_status; | |
879 | ||
880 | if (status == GNTST_okay) | |
881 | continue; | |
882 | ||
883 | if (__get_user(old_status, batch->status[i])) | |
884 | return -EFAULT; | |
885 | ||
886 | if (old_status != GNTST_okay) | |
887 | continue; | |
888 | ||
889 | if (__put_user(status, batch->status[i])) | |
890 | return -EFAULT; | |
891 | } | |
892 | ||
893 | batch->nr_ops = 0; | |
894 | return 0; | |
895 | } | |
896 | ||
897 | static int gntdev_grant_copy_seg(struct gntdev_copy_batch *batch, | |
898 | struct gntdev_grant_copy_segment *seg, | |
899 | s16 __user *status) | |
900 | { | |
901 | uint16_t copied = 0; | |
902 | ||
903 | /* | |
904 | * Disallow local -> local copies since there is only space in | |
905 | * batch->pages for one page per-op and this would be a very | |
906 | * expensive memcpy(). | |
907 | */ | |
908 | if (!(seg->flags & (GNTCOPY_source_gref | GNTCOPY_dest_gref))) | |
909 | return -EINVAL; | |
910 | ||
911 | /* Can't cross page if source/dest is a grant ref. */ | |
912 | if (seg->flags & GNTCOPY_source_gref) { | |
913 | if (seg->source.foreign.offset + seg->len > XEN_PAGE_SIZE) | |
914 | return -EINVAL; | |
915 | } | |
916 | if (seg->flags & GNTCOPY_dest_gref) { | |
917 | if (seg->dest.foreign.offset + seg->len > XEN_PAGE_SIZE) | |
918 | return -EINVAL; | |
919 | } | |
920 | ||
921 | if (put_user(GNTST_okay, status)) | |
922 | return -EFAULT; | |
923 | ||
924 | while (copied < seg->len) { | |
925 | struct gnttab_copy *op; | |
926 | void __user *virt; | |
927 | size_t len, off; | |
928 | unsigned long gfn; | |
929 | int ret; | |
930 | ||
931 | if (batch->nr_ops >= GNTDEV_COPY_BATCH) { | |
932 | ret = gntdev_copy(batch); | |
933 | if (ret < 0) | |
934 | return ret; | |
935 | } | |
936 | ||
937 | len = seg->len - copied; | |
938 | ||
939 | op = &batch->ops[batch->nr_ops]; | |
940 | op->flags = 0; | |
941 | ||
942 | if (seg->flags & GNTCOPY_source_gref) { | |
943 | op->source.u.ref = seg->source.foreign.ref; | |
944 | op->source.domid = seg->source.foreign.domid; | |
945 | op->source.offset = seg->source.foreign.offset + copied; | |
946 | op->flags |= GNTCOPY_source_gref; | |
947 | } else { | |
948 | virt = seg->source.virt + copied; | |
949 | off = (unsigned long)virt & ~XEN_PAGE_MASK; | |
950 | len = min(len, (size_t)XEN_PAGE_SIZE - off); | |
951 | ||
952 | ret = gntdev_get_page(batch, virt, false, &gfn); | |
953 | if (ret < 0) | |
954 | return ret; | |
955 | ||
956 | op->source.u.gmfn = gfn; | |
957 | op->source.domid = DOMID_SELF; | |
958 | op->source.offset = off; | |
959 | } | |
960 | ||
961 | if (seg->flags & GNTCOPY_dest_gref) { | |
962 | op->dest.u.ref = seg->dest.foreign.ref; | |
963 | op->dest.domid = seg->dest.foreign.domid; | |
964 | op->dest.offset = seg->dest.foreign.offset + copied; | |
965 | op->flags |= GNTCOPY_dest_gref; | |
966 | } else { | |
967 | virt = seg->dest.virt + copied; | |
968 | off = (unsigned long)virt & ~XEN_PAGE_MASK; | |
969 | len = min(len, (size_t)XEN_PAGE_SIZE - off); | |
970 | ||
971 | ret = gntdev_get_page(batch, virt, true, &gfn); | |
972 | if (ret < 0) | |
973 | return ret; | |
974 | ||
975 | op->dest.u.gmfn = gfn; | |
976 | op->dest.domid = DOMID_SELF; | |
977 | op->dest.offset = off; | |
978 | } | |
979 | ||
980 | op->len = len; | |
981 | copied += len; | |
982 | ||
983 | batch->status[batch->nr_ops] = status; | |
984 | batch->nr_ops++; | |
985 | } | |
986 | ||
987 | return 0; | |
988 | } | |
989 | ||
990 | static long gntdev_ioctl_grant_copy(struct gntdev_priv *priv, void __user *u) | |
991 | { | |
992 | struct ioctl_gntdev_grant_copy copy; | |
993 | struct gntdev_copy_batch batch; | |
994 | unsigned int i; | |
995 | int ret = 0; | |
996 | ||
997 | if (copy_from_user(©, u, sizeof(copy))) | |
998 | return -EFAULT; | |
999 | ||
1000 | batch.nr_ops = 0; | |
1001 | batch.nr_pages = 0; | |
1002 | ||
1003 | for (i = 0; i < copy.count; i++) { | |
1004 | struct gntdev_grant_copy_segment seg; | |
1005 | ||
1006 | if (copy_from_user(&seg, ©.segments[i], sizeof(seg))) { | |
1007 | ret = -EFAULT; | |
1008 | goto out; | |
1009 | } | |
1010 | ||
1011 | ret = gntdev_grant_copy_seg(&batch, &seg, ©.segments[i].status); | |
1012 | if (ret < 0) | |
1013 | goto out; | |
1014 | ||
1015 | cond_resched(); | |
1016 | } | |
1017 | if (batch.nr_ops) | |
1018 | ret = gntdev_copy(&batch); | |
1019 | return ret; | |
1020 | ||
1021 | out: | |
1022 | gntdev_put_pages(&batch); | |
1023 | return ret; | |
1024 | } | |
1025 | ||
ab31523c GH |
1026 | static long gntdev_ioctl(struct file *flip, |
1027 | unsigned int cmd, unsigned long arg) | |
1028 | { | |
1029 | struct gntdev_priv *priv = flip->private_data; | |
1030 | void __user *ptr = (void __user *)arg; | |
1031 | ||
1032 | switch (cmd) { | |
1033 | case IOCTL_GNTDEV_MAP_GRANT_REF: | |
1034 | return gntdev_ioctl_map_grant_ref(priv, ptr); | |
1035 | ||
1036 | case IOCTL_GNTDEV_UNMAP_GRANT_REF: | |
1037 | return gntdev_ioctl_unmap_grant_ref(priv, ptr); | |
1038 | ||
1039 | case IOCTL_GNTDEV_GET_OFFSET_FOR_VADDR: | |
1040 | return gntdev_ioctl_get_offset_for_vaddr(priv, ptr); | |
1041 | ||
bdc612dc DDG |
1042 | case IOCTL_GNTDEV_SET_UNMAP_NOTIFY: |
1043 | return gntdev_ioctl_notify(priv, ptr); | |
1044 | ||
a4cdb556 DV |
1045 | case IOCTL_GNTDEV_GRANT_COPY: |
1046 | return gntdev_ioctl_grant_copy(priv, ptr); | |
1047 | ||
932d6562 OA |
1048 | #ifdef CONFIG_XEN_GNTDEV_DMABUF |
1049 | case IOCTL_GNTDEV_DMABUF_EXP_FROM_REFS: | |
1050 | return gntdev_ioctl_dmabuf_exp_from_refs(priv, use_ptemod, ptr); | |
1051 | ||
1052 | case IOCTL_GNTDEV_DMABUF_EXP_WAIT_RELEASED: | |
1053 | return gntdev_ioctl_dmabuf_exp_wait_released(priv, ptr); | |
1054 | ||
1055 | case IOCTL_GNTDEV_DMABUF_IMP_TO_REFS: | |
1056 | return gntdev_ioctl_dmabuf_imp_to_refs(priv, ptr); | |
1057 | ||
1058 | case IOCTL_GNTDEV_DMABUF_IMP_RELEASE: | |
1059 | return gntdev_ioctl_dmabuf_imp_release(priv, ptr); | |
1060 | #endif | |
1061 | ||
ab31523c GH |
1062 | default: |
1063 | pr_debug("priv %p, unknown cmd %x\n", priv, cmd); | |
1064 | return -ENOIOCTLCMD; | |
1065 | } | |
1066 | ||
1067 | return 0; | |
1068 | } | |
1069 | ||
1070 | static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) | |
1071 | { | |
1072 | struct gntdev_priv *priv = flip->private_data; | |
1073 | int index = vma->vm_pgoff; | |
c7ebf9d9 | 1074 | int count = vma_pages(vma); |
1d314567 | 1075 | struct gntdev_grant_map *map; |
df9bde01 | 1076 | int err = -EINVAL; |
ab31523c GH |
1077 | |
1078 | if ((vma->vm_flags & VM_WRITE) && !(vma->vm_flags & VM_SHARED)) | |
1079 | return -EINVAL; | |
1080 | ||
1081 | pr_debug("map %d+%d at %lx (pgoff %lx)\n", | |
1082 | index, count, vma->vm_start, vma->vm_pgoff); | |
1083 | ||
1401c00e | 1084 | mutex_lock(&priv->lock); |
ab31523c GH |
1085 | map = gntdev_find_map_index(priv, index, count); |
1086 | if (!map) | |
1087 | goto unlock_out; | |
aab8f11a | 1088 | if (use_ptemod && map->vma) |
ab31523c | 1089 | goto unlock_out; |
aab8f11a | 1090 | if (use_ptemod && priv->mm != vma->vm_mm) { |
283c0972 | 1091 | pr_warn("Huh? Other mm?\n"); |
ab31523c GH |
1092 | goto unlock_out; |
1093 | } | |
1094 | ||
c5f7c5a9 | 1095 | refcount_inc(&map->users); |
68b025c8 | 1096 | |
ab31523c GH |
1097 | vma->vm_ops = &gntdev_vmops; |
1098 | ||
30faaafd | 1099 | vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP | VM_MIXEDMAP; |
d79647ae DDG |
1100 | |
1101 | if (use_ptemod) | |
e8e937be | 1102 | vma->vm_flags |= VM_DONTCOPY; |
ab31523c GH |
1103 | |
1104 | vma->vm_private_data = map; | |
ab31523c | 1105 | |
aab8f11a DDG |
1106 | if (use_ptemod) |
1107 | map->vma = vma; | |
1108 | ||
12996fc3 DDG |
1109 | if (map->flags) { |
1110 | if ((vma->vm_flags & VM_WRITE) && | |
1111 | (map->flags & GNTMAP_readonly)) | |
a93e20a8 | 1112 | goto out_unlock_put; |
12996fc3 DDG |
1113 | } else { |
1114 | map->flags = GNTMAP_host_map; | |
1115 | if (!(vma->vm_flags & VM_WRITE)) | |
1116 | map->flags |= GNTMAP_readonly; | |
1117 | } | |
ab31523c | 1118 | |
1401c00e | 1119 | mutex_unlock(&priv->lock); |
f0a70c88 | 1120 | |
aab8f11a | 1121 | if (use_ptemod) { |
298d275d | 1122 | map->pages_vm_start = vma->vm_start; |
aab8f11a DDG |
1123 | err = apply_to_page_range(vma->vm_mm, vma->vm_start, |
1124 | vma->vm_end - vma->vm_start, | |
1125 | find_grant_ptes, map); | |
1126 | if (err) { | |
283c0972 | 1127 | pr_warn("find_grant_ptes() failure.\n"); |
90b6f305 | 1128 | goto out_put_map; |
aab8f11a | 1129 | } |
ab31523c GH |
1130 | } |
1131 | ||
1d314567 | 1132 | err = gntdev_map_grant_pages(map); |
90b6f305 DDG |
1133 | if (err) |
1134 | goto out_put_map; | |
f0a70c88 | 1135 | |
aab8f11a | 1136 | if (!use_ptemod) { |
8d1502f6 | 1137 | err = vm_map_pages_zero(vma, map->pages, map->count); |
df9bde01 SJ |
1138 | if (err) |
1139 | goto out_put_map; | |
923b2919 DV |
1140 | } else { |
1141 | #ifdef CONFIG_X86 | |
1142 | /* | |
1143 | * If the PTEs were not made special by the grant map | |
1144 | * hypercall, do so here. | |
1145 | * | |
1146 | * This is racy since the mapping is already visible | |
1147 | * to userspace but userspace should be well-behaved | |
1148 | * enough to not touch it until the mmap() call | |
1149 | * returns. | |
1150 | */ | |
1151 | if (!xen_feature(XENFEAT_gnttab_map_avail_bits)) { | |
1152 | apply_to_page_range(vma->vm_mm, vma->vm_start, | |
1153 | vma->vm_end - vma->vm_start, | |
1154 | set_grant_ptes_as_special, NULL); | |
1155 | } | |
1156 | #endif | |
aab8f11a DDG |
1157 | } |
1158 | ||
f0a70c88 DDG |
1159 | return 0; |
1160 | ||
ab31523c | 1161 | unlock_out: |
1401c00e | 1162 | mutex_unlock(&priv->lock); |
ab31523c | 1163 | return err; |
90b6f305 | 1164 | |
a93e20a8 | 1165 | out_unlock_put: |
1401c00e | 1166 | mutex_unlock(&priv->lock); |
90b6f305 | 1167 | out_put_map: |
cf2acf66 | 1168 | if (use_ptemod) { |
84e4075d | 1169 | map->vma = NULL; |
cf2acf66 RL |
1170 | unmap_grant_pages(map, 0, map->count); |
1171 | } | |
16a1d022 | 1172 | gntdev_put_map(priv, map); |
90b6f305 | 1173 | return err; |
ab31523c GH |
1174 | } |
1175 | ||
1176 | static const struct file_operations gntdev_fops = { | |
1177 | .owner = THIS_MODULE, | |
1178 | .open = gntdev_open, | |
1179 | .release = gntdev_release, | |
1180 | .mmap = gntdev_mmap, | |
1181 | .unlocked_ioctl = gntdev_ioctl | |
1182 | }; | |
1183 | ||
1184 | static struct miscdevice gntdev_miscdev = { | |
1185 | .minor = MISC_DYNAMIC_MINOR, | |
1186 | .name = "xen/gntdev", | |
1187 | .fops = &gntdev_fops, | |
1188 | }; | |
1189 | ||
1190 | /* ------------------------------------------------------------------ */ | |
1191 | ||
1192 | static int __init gntdev_init(void) | |
1193 | { | |
1194 | int err; | |
1195 | ||
1196 | if (!xen_domain()) | |
1197 | return -ENODEV; | |
1198 | ||
6926f6d6 | 1199 | use_ptemod = !xen_feature(XENFEAT_auto_translated_physmap); |
aab8f11a | 1200 | |
ab31523c GH |
1201 | err = misc_register(&gntdev_miscdev); |
1202 | if (err != 0) { | |
283c0972 | 1203 | pr_err("Could not register gntdev device\n"); |
ab31523c GH |
1204 | return err; |
1205 | } | |
1206 | return 0; | |
1207 | } | |
1208 | ||
1209 | static void __exit gntdev_exit(void) | |
1210 | { | |
1211 | misc_deregister(&gntdev_miscdev); | |
1212 | } | |
1213 | ||
1214 | module_init(gntdev_init); | |
1215 | module_exit(gntdev_exit); | |
1216 | ||
1217 | /* ------------------------------------------------------------------ */ |