Commit | Line | Data |
---|---|---|
1c5de193 JF |
1 | /****************************************************************************** |
2 | * privcmd.c | |
3 | * | |
4 | * Interface to privileged domain-0 commands. | |
5 | * | |
6 | * Copyright (c) 2002-2004, K A Fraser, B Dragovic | |
7 | */ | |
8 | ||
283c0972 JP |
9 | #define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt |
10 | ||
1c5de193 | 11 | #include <linux/kernel.h> |
d8414d3c | 12 | #include <linux/module.h> |
1c5de193 JF |
13 | #include <linux/sched.h> |
14 | #include <linux/slab.h> | |
15 | #include <linux/string.h> | |
16 | #include <linux/errno.h> | |
17 | #include <linux/mm.h> | |
18 | #include <linux/mman.h> | |
19 | #include <linux/uaccess.h> | |
20 | #include <linux/swap.h> | |
1c5de193 JF |
21 | #include <linux/highmem.h> |
22 | #include <linux/pagemap.h> | |
23 | #include <linux/seq_file.h> | |
d8414d3c | 24 | #include <linux/miscdevice.h> |
1c5de193 JF |
25 | |
26 | #include <asm/pgalloc.h> | |
27 | #include <asm/pgtable.h> | |
28 | #include <asm/tlb.h> | |
29 | #include <asm/xen/hypervisor.h> | |
30 | #include <asm/xen/hypercall.h> | |
31 | ||
32 | #include <xen/xen.h> | |
33 | #include <xen/privcmd.h> | |
34 | #include <xen/interface/xen.h> | |
35 | #include <xen/features.h> | |
36 | #include <xen/page.h> | |
de1ef206 | 37 | #include <xen/xen-ops.h> |
d71f5139 | 38 | #include <xen/balloon.h> |
f020e290 | 39 | |
d8414d3c BB |
40 | #include "privcmd.h" |
41 | ||
42 | MODULE_LICENSE("GPL"); | |
43 | ||
d71f5139 MR |
44 | #define PRIV_VMA_LOCKED ((void *)1) |
45 | ||
a5deabe0 ALC |
46 | static int privcmd_vma_range_is_mapped( |
47 | struct vm_area_struct *vma, | |
48 | unsigned long addr, | |
49 | unsigned long nr_pages); | |
1c5de193 | 50 | |
1c5de193 JF |
51 | static long privcmd_ioctl_hypercall(void __user *udata) |
52 | { | |
53 | struct privcmd_hypercall hypercall; | |
54 | long ret; | |
55 | ||
56 | if (copy_from_user(&hypercall, udata, sizeof(hypercall))) | |
57 | return -EFAULT; | |
58 | ||
fdfd811d | 59 | xen_preemptible_hcall_begin(); |
1c5de193 JF |
60 | ret = privcmd_call(hypercall.op, |
61 | hypercall.arg[0], hypercall.arg[1], | |
62 | hypercall.arg[2], hypercall.arg[3], | |
63 | hypercall.arg[4]); | |
fdfd811d | 64 | xen_preemptible_hcall_end(); |
1c5de193 JF |
65 | |
66 | return ret; | |
67 | } | |
68 | ||
69 | static void free_page_list(struct list_head *pages) | |
70 | { | |
71 | struct page *p, *n; | |
72 | ||
73 | list_for_each_entry_safe(p, n, pages, lru) | |
74 | __free_page(p); | |
75 | ||
76 | INIT_LIST_HEAD(pages); | |
77 | } | |
78 | ||
79 | /* | |
80 | * Given an array of items in userspace, return a list of pages | |
81 | * containing the data. If copying fails, either because of memory | |
82 | * allocation failure or a problem reading user memory, return an | |
83 | * error code; its up to the caller to dispose of any partial list. | |
84 | */ | |
85 | static int gather_array(struct list_head *pagelist, | |
86 | unsigned nelem, size_t size, | |
ceb90fa0 | 87 | const void __user *data) |
1c5de193 JF |
88 | { |
89 | unsigned pageidx; | |
90 | void *pagedata; | |
91 | int ret; | |
92 | ||
93 | if (size > PAGE_SIZE) | |
94 | return 0; | |
95 | ||
96 | pageidx = PAGE_SIZE; | |
97 | pagedata = NULL; /* quiet, gcc */ | |
98 | while (nelem--) { | |
99 | if (pageidx > PAGE_SIZE-size) { | |
100 | struct page *page = alloc_page(GFP_KERNEL); | |
101 | ||
102 | ret = -ENOMEM; | |
103 | if (page == NULL) | |
104 | goto fail; | |
105 | ||
106 | pagedata = page_address(page); | |
107 | ||
108 | list_add_tail(&page->lru, pagelist); | |
109 | pageidx = 0; | |
110 | } | |
111 | ||
112 | ret = -EFAULT; | |
113 | if (copy_from_user(pagedata + pageidx, data, size)) | |
114 | goto fail; | |
115 | ||
116 | data += size; | |
117 | pageidx += size; | |
118 | } | |
119 | ||
120 | ret = 0; | |
121 | ||
122 | fail: | |
123 | return ret; | |
124 | } | |
125 | ||
126 | /* | |
127 | * Call function "fn" on each element of the array fragmented | |
128 | * over a list of pages. | |
129 | */ | |
130 | static int traverse_pages(unsigned nelem, size_t size, | |
131 | struct list_head *pos, | |
132 | int (*fn)(void *data, void *state), | |
133 | void *state) | |
134 | { | |
135 | void *pagedata; | |
136 | unsigned pageidx; | |
f020e290 | 137 | int ret = 0; |
1c5de193 JF |
138 | |
139 | BUG_ON(size > PAGE_SIZE); | |
140 | ||
141 | pageidx = PAGE_SIZE; | |
142 | pagedata = NULL; /* hush, gcc */ | |
143 | ||
144 | while (nelem--) { | |
145 | if (pageidx > PAGE_SIZE-size) { | |
146 | struct page *page; | |
147 | pos = pos->next; | |
148 | page = list_entry(pos, struct page, lru); | |
149 | pagedata = page_address(page); | |
150 | pageidx = 0; | |
151 | } | |
152 | ||
153 | ret = (*fn)(pagedata + pageidx, state); | |
154 | if (ret) | |
155 | break; | |
156 | pageidx += size; | |
157 | } | |
158 | ||
159 | return ret; | |
160 | } | |
161 | ||
162 | struct mmap_mfn_state { | |
163 | unsigned long va; | |
164 | struct vm_area_struct *vma; | |
165 | domid_t domain; | |
166 | }; | |
167 | ||
168 | static int mmap_mfn_range(void *data, void *state) | |
169 | { | |
170 | struct privcmd_mmap_entry *msg = data; | |
171 | struct mmap_mfn_state *st = state; | |
172 | struct vm_area_struct *vma = st->vma; | |
173 | int rc; | |
174 | ||
175 | /* Do not allow range to wrap the address space. */ | |
176 | if ((msg->npages > (LONG_MAX >> PAGE_SHIFT)) || | |
177 | ((unsigned long)(msg->npages << PAGE_SHIFT) >= -st->va)) | |
178 | return -EINVAL; | |
179 | ||
180 | /* Range chunks must be contiguous in va space. */ | |
181 | if ((msg->va != st->va) || | |
182 | ((msg->va+(msg->npages<<PAGE_SHIFT)) > vma->vm_end)) | |
183 | return -EINVAL; | |
184 | ||
de1ef206 IC |
185 | rc = xen_remap_domain_mfn_range(vma, |
186 | msg->va & PAGE_MASK, | |
187 | msg->mfn, msg->npages, | |
188 | vma->vm_page_prot, | |
9a032e39 | 189 | st->domain, NULL); |
1c5de193 JF |
190 | if (rc < 0) |
191 | return rc; | |
192 | ||
193 | st->va += msg->npages << PAGE_SHIFT; | |
194 | ||
195 | return 0; | |
196 | } | |
197 | ||
198 | static long privcmd_ioctl_mmap(void __user *udata) | |
199 | { | |
200 | struct privcmd_mmap mmapcmd; | |
201 | struct mm_struct *mm = current->mm; | |
202 | struct vm_area_struct *vma; | |
203 | int rc; | |
204 | LIST_HEAD(pagelist); | |
205 | struct mmap_mfn_state state; | |
206 | ||
d71f5139 MR |
207 | /* We only support privcmd_ioctl_mmap_batch for auto translated. */ |
208 | if (xen_feature(XENFEAT_auto_translated_physmap)) | |
209 | return -ENOSYS; | |
210 | ||
1c5de193 JF |
211 | if (copy_from_user(&mmapcmd, udata, sizeof(mmapcmd))) |
212 | return -EFAULT; | |
213 | ||
214 | rc = gather_array(&pagelist, | |
215 | mmapcmd.num, sizeof(struct privcmd_mmap_entry), | |
216 | mmapcmd.entry); | |
217 | ||
218 | if (rc || list_empty(&pagelist)) | |
219 | goto out; | |
220 | ||
221 | down_write(&mm->mmap_sem); | |
222 | ||
223 | { | |
224 | struct page *page = list_first_entry(&pagelist, | |
225 | struct page, lru); | |
226 | struct privcmd_mmap_entry *msg = page_address(page); | |
227 | ||
228 | vma = find_vma(mm, msg->va); | |
229 | rc = -EINVAL; | |
230 | ||
a5deabe0 | 231 | if (!vma || (msg->va != vma->vm_start) || vma->vm_private_data) |
1c5de193 | 232 | goto out_up; |
a5deabe0 | 233 | vma->vm_private_data = PRIV_VMA_LOCKED; |
1c5de193 JF |
234 | } |
235 | ||
236 | state.va = vma->vm_start; | |
237 | state.vma = vma; | |
238 | state.domain = mmapcmd.dom; | |
239 | ||
240 | rc = traverse_pages(mmapcmd.num, sizeof(struct privcmd_mmap_entry), | |
241 | &pagelist, | |
242 | mmap_mfn_range, &state); | |
243 | ||
244 | ||
245 | out_up: | |
246 | up_write(&mm->mmap_sem); | |
247 | ||
248 | out: | |
249 | free_page_list(&pagelist); | |
250 | ||
251 | return rc; | |
252 | } | |
253 | ||
254 | struct mmap_batch_state { | |
255 | domid_t domain; | |
256 | unsigned long va; | |
257 | struct vm_area_struct *vma; | |
d71f5139 | 258 | int index; |
ceb90fa0 ALC |
259 | /* A tristate: |
260 | * 0 for no errors | |
261 | * 1 if at least one error has happened (and no | |
262 | * -ENOENT errors have happened) | |
263 | * -ENOENT if at least 1 -ENOENT has happened. | |
264 | */ | |
265 | int global_error; | |
99beae6c | 266 | int version; |
ceb90fa0 ALC |
267 | |
268 | /* User-space mfn array to store errors in the second pass for V1. */ | |
269 | xen_pfn_t __user *user_mfn; | |
99beae6c ALC |
270 | /* User-space int array to store errors in the second pass for V2. */ |
271 | int __user *user_err; | |
1c5de193 JF |
272 | }; |
273 | ||
d71f5139 MR |
274 | /* auto translated dom0 note: if domU being created is PV, then mfn is |
275 | * mfn(addr on bus). If it's auto xlated, then mfn is pfn (input to HAP). | |
276 | */ | |
1c5de193 JF |
277 | static int mmap_batch_fn(void *data, void *state) |
278 | { | |
279 | xen_pfn_t *mfnp = data; | |
280 | struct mmap_batch_state *st = state; | |
d71f5139 MR |
281 | struct vm_area_struct *vma = st->vma; |
282 | struct page **pages = vma->vm_private_data; | |
283 | struct page *cur_page = NULL; | |
ceb90fa0 ALC |
284 | int ret; |
285 | ||
d71f5139 MR |
286 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
287 | cur_page = pages[st->index++]; | |
288 | ||
ceb90fa0 | 289 | ret = xen_remap_domain_mfn_range(st->vma, st->va & PAGE_MASK, *mfnp, 1, |
9a032e39 | 290 | st->vma->vm_page_prot, st->domain, |
d71f5139 | 291 | &cur_page); |
1c5de193 | 292 | |
ceb90fa0 | 293 | /* Store error code for second pass. */ |
99beae6c ALC |
294 | if (st->version == 1) { |
295 | if (ret < 0) { | |
296 | /* | |
297 | * V1 encodes the error codes in the 32bit top nibble of the | |
298 | * mfn (with its known limitations vis-a-vis 64 bit callers). | |
299 | */ | |
300 | *mfnp |= (ret == -ENOENT) ? | |
301 | PRIVCMD_MMAPBATCH_PAGED_ERROR : | |
302 | PRIVCMD_MMAPBATCH_MFN_ERROR; | |
303 | } | |
304 | } else { /* st->version == 2 */ | |
305 | *((int *) mfnp) = ret; | |
306 | } | |
ceb90fa0 ALC |
307 | |
308 | /* And see if it affects the global_error. */ | |
309 | if (ret < 0) { | |
310 | if (ret == -ENOENT) | |
311 | st->global_error = -ENOENT; | |
312 | else { | |
313 | /* Record that at least one error has happened. */ | |
314 | if (st->global_error == 0) | |
315 | st->global_error = 1; | |
316 | } | |
1c5de193 JF |
317 | } |
318 | st->va += PAGE_SIZE; | |
319 | ||
320 | return 0; | |
321 | } | |
322 | ||
99beae6c | 323 | static int mmap_return_errors(void *data, void *state) |
1c5de193 | 324 | { |
1c5de193 | 325 | struct mmap_batch_state *st = state; |
ceb90fa0 | 326 | |
99beae6c ALC |
327 | if (st->version == 1) { |
328 | xen_pfn_t mfnp = *((xen_pfn_t *) data); | |
329 | if (mfnp & PRIVCMD_MMAPBATCH_MFN_ERROR) | |
330 | return __put_user(mfnp, st->user_mfn++); | |
331 | else | |
332 | st->user_mfn++; | |
333 | } else { /* st->version == 2 */ | |
334 | int err = *((int *) data); | |
335 | if (err) | |
336 | return __put_user(err, st->user_err++); | |
337 | else | |
338 | st->user_err++; | |
339 | } | |
340 | ||
341 | return 0; | |
1c5de193 JF |
342 | } |
343 | ||
d71f5139 MR |
344 | /* Allocate pfns that are then mapped with gmfns from foreign domid. Update |
345 | * the vma with the page info to use later. | |
346 | * Returns: 0 if success, otherwise -errno | |
347 | */ | |
348 | static int alloc_empty_pages(struct vm_area_struct *vma, int numpgs) | |
349 | { | |
350 | int rc; | |
351 | struct page **pages; | |
352 | ||
353 | pages = kcalloc(numpgs, sizeof(pages[0]), GFP_KERNEL); | |
354 | if (pages == NULL) | |
355 | return -ENOMEM; | |
356 | ||
357 | rc = alloc_xenballooned_pages(numpgs, pages, 0); | |
358 | if (rc != 0) { | |
359 | pr_warn("%s Could not alloc %d pfns rc:%d\n", __func__, | |
360 | numpgs, rc); | |
361 | kfree(pages); | |
362 | return -ENOMEM; | |
363 | } | |
a5deabe0 | 364 | BUG_ON(vma->vm_private_data != NULL); |
d71f5139 MR |
365 | vma->vm_private_data = pages; |
366 | ||
367 | return 0; | |
368 | } | |
369 | ||
f31fdf51 JF |
370 | static struct vm_operations_struct privcmd_vm_ops; |
371 | ||
ceb90fa0 | 372 | static long privcmd_ioctl_mmap_batch(void __user *udata, int version) |
1c5de193 JF |
373 | { |
374 | int ret; | |
ceb90fa0 | 375 | struct privcmd_mmapbatch_v2 m; |
1c5de193 JF |
376 | struct mm_struct *mm = current->mm; |
377 | struct vm_area_struct *vma; | |
378 | unsigned long nr_pages; | |
379 | LIST_HEAD(pagelist); | |
380 | struct mmap_batch_state state; | |
381 | ||
ceb90fa0 ALC |
382 | switch (version) { |
383 | case 1: | |
384 | if (copy_from_user(&m, udata, sizeof(struct privcmd_mmapbatch))) | |
385 | return -EFAULT; | |
386 | /* Returns per-frame error in m.arr. */ | |
387 | m.err = NULL; | |
388 | if (!access_ok(VERIFY_WRITE, m.arr, m.num * sizeof(*m.arr))) | |
389 | return -EFAULT; | |
390 | break; | |
391 | case 2: | |
392 | if (copy_from_user(&m, udata, sizeof(struct privcmd_mmapbatch_v2))) | |
393 | return -EFAULT; | |
394 | /* Returns per-frame error code in m.err. */ | |
395 | if (!access_ok(VERIFY_WRITE, m.err, m.num * (sizeof(*m.err)))) | |
396 | return -EFAULT; | |
397 | break; | |
398 | default: | |
399 | return -EINVAL; | |
400 | } | |
1c5de193 JF |
401 | |
402 | nr_pages = m.num; | |
403 | if ((m.num <= 0) || (nr_pages > (LONG_MAX >> PAGE_SHIFT))) | |
404 | return -EINVAL; | |
405 | ||
ceb90fa0 | 406 | ret = gather_array(&pagelist, m.num, sizeof(xen_pfn_t), m.arr); |
1c5de193 | 407 | |
ceb90fa0 | 408 | if (ret) |
1c5de193 | 409 | goto out; |
ceb90fa0 ALC |
410 | if (list_empty(&pagelist)) { |
411 | ret = -EINVAL; | |
412 | goto out; | |
413 | } | |
414 | ||
99beae6c ALC |
415 | if (version == 2) { |
416 | /* Zero error array now to only copy back actual errors. */ | |
417 | if (clear_user(m.err, sizeof(int) * m.num)) { | |
418 | ret = -EFAULT; | |
419 | goto out; | |
420 | } | |
ceb90fa0 | 421 | } |
1c5de193 JF |
422 | |
423 | down_write(&mm->mmap_sem); | |
424 | ||
425 | vma = find_vma(mm, m.addr); | |
1c5de193 | 426 | if (!vma || |
a5deabe0 | 427 | vma->vm_ops != &privcmd_vm_ops) { |
68fa965d | 428 | ret = -EINVAL; |
a5deabe0 | 429 | goto out_unlock; |
1c5de193 | 430 | } |
a5deabe0 ALC |
431 | |
432 | /* | |
433 | * Caller must either: | |
434 | * | |
435 | * Map the whole VMA range, which will also allocate all the | |
436 | * pages required for the auto_translated_physmap case. | |
437 | * | |
438 | * Or | |
439 | * | |
440 | * Map unmapped holes left from a previous map attempt (e.g., | |
441 | * because those foreign frames were previously paged out). | |
442 | */ | |
443 | if (vma->vm_private_data == NULL) { | |
444 | if (m.addr != vma->vm_start || | |
445 | m.addr + (nr_pages << PAGE_SHIFT) != vma->vm_end) { | |
446 | ret = -EINVAL; | |
447 | goto out_unlock; | |
448 | } | |
449 | if (xen_feature(XENFEAT_auto_translated_physmap)) { | |
450 | ret = alloc_empty_pages(vma, m.num); | |
451 | if (ret < 0) | |
452 | goto out_unlock; | |
453 | } else | |
454 | vma->vm_private_data = PRIV_VMA_LOCKED; | |
455 | } else { | |
456 | if (m.addr < vma->vm_start || | |
457 | m.addr + (nr_pages << PAGE_SHIFT) > vma->vm_end) { | |
458 | ret = -EINVAL; | |
459 | goto out_unlock; | |
460 | } | |
461 | if (privcmd_vma_range_is_mapped(vma, m.addr, nr_pages)) { | |
462 | ret = -EINVAL; | |
463 | goto out_unlock; | |
d71f5139 MR |
464 | } |
465 | } | |
1c5de193 | 466 | |
ceb90fa0 ALC |
467 | state.domain = m.dom; |
468 | state.vma = vma; | |
469 | state.va = m.addr; | |
d71f5139 | 470 | state.index = 0; |
ceb90fa0 | 471 | state.global_error = 0; |
99beae6c | 472 | state.version = version; |
1c5de193 | 473 | |
ceb90fa0 ALC |
474 | /* mmap_batch_fn guarantees ret == 0 */ |
475 | BUG_ON(traverse_pages(m.num, sizeof(xen_pfn_t), | |
476 | &pagelist, mmap_batch_fn, &state)); | |
1c5de193 JF |
477 | |
478 | up_write(&mm->mmap_sem); | |
479 | ||
99beae6c ALC |
480 | if (state.global_error) { |
481 | /* Write back errors in second pass. */ | |
482 | state.user_mfn = (xen_pfn_t *)m.arr; | |
483 | state.user_err = m.err; | |
484 | ret = traverse_pages(m.num, sizeof(xen_pfn_t), | |
485 | &pagelist, mmap_return_errors, &state); | |
486 | } else | |
487 | ret = 0; | |
ceb90fa0 ALC |
488 | |
489 | /* If we have not had any EFAULT-like global errors then set the global | |
490 | * error to -ENOENT if necessary. */ | |
491 | if ((ret == 0) && (state.global_error == -ENOENT)) | |
492 | ret = -ENOENT; | |
1c5de193 JF |
493 | |
494 | out: | |
495 | free_page_list(&pagelist); | |
1c5de193 | 496 | return ret; |
a5deabe0 ALC |
497 | |
498 | out_unlock: | |
499 | up_write(&mm->mmap_sem); | |
500 | goto out; | |
1c5de193 JF |
501 | } |
502 | ||
503 | static long privcmd_ioctl(struct file *file, | |
504 | unsigned int cmd, unsigned long data) | |
505 | { | |
506 | int ret = -ENOSYS; | |
507 | void __user *udata = (void __user *) data; | |
508 | ||
509 | switch (cmd) { | |
510 | case IOCTL_PRIVCMD_HYPERCALL: | |
511 | ret = privcmd_ioctl_hypercall(udata); | |
512 | break; | |
513 | ||
514 | case IOCTL_PRIVCMD_MMAP: | |
515 | ret = privcmd_ioctl_mmap(udata); | |
516 | break; | |
517 | ||
518 | case IOCTL_PRIVCMD_MMAPBATCH: | |
ceb90fa0 ALC |
519 | ret = privcmd_ioctl_mmap_batch(udata, 1); |
520 | break; | |
521 | ||
522 | case IOCTL_PRIVCMD_MMAPBATCH_V2: | |
523 | ret = privcmd_ioctl_mmap_batch(udata, 2); | |
1c5de193 JF |
524 | break; |
525 | ||
526 | default: | |
527 | ret = -EINVAL; | |
528 | break; | |
529 | } | |
530 | ||
531 | return ret; | |
532 | } | |
533 | ||
d71f5139 MR |
534 | static void privcmd_close(struct vm_area_struct *vma) |
535 | { | |
536 | struct page **pages = vma->vm_private_data; | |
537 | int numpgs = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; | |
b6497b38 | 538 | int rc; |
d71f5139 | 539 | |
9eff37a8 | 540 | if (!xen_feature(XENFEAT_auto_translated_physmap) || !numpgs || !pages) |
d71f5139 MR |
541 | return; |
542 | ||
b6497b38 IC |
543 | rc = xen_unmap_domain_mfn_range(vma, numpgs, pages); |
544 | if (rc == 0) | |
545 | free_xenballooned_pages(numpgs, pages); | |
546 | else | |
547 | pr_crit("unable to unmap MFN range: leaking %d pages. rc=%d\n", | |
548 | numpgs, rc); | |
d71f5139 MR |
549 | kfree(pages); |
550 | } | |
551 | ||
1c5de193 JF |
552 | static int privcmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
553 | { | |
441c7416 JF |
554 | printk(KERN_DEBUG "privcmd_fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n", |
555 | vma, vma->vm_start, vma->vm_end, | |
556 | vmf->pgoff, vmf->virtual_address); | |
557 | ||
1c5de193 JF |
558 | return VM_FAULT_SIGBUS; |
559 | } | |
560 | ||
561 | static struct vm_operations_struct privcmd_vm_ops = { | |
d71f5139 | 562 | .close = privcmd_close, |
1c5de193 JF |
563 | .fault = privcmd_fault |
564 | }; | |
565 | ||
566 | static int privcmd_mmap(struct file *file, struct vm_area_struct *vma) | |
567 | { | |
e060e7af SS |
568 | /* DONTCOPY is essential for Xen because copy_page_range doesn't know |
569 | * how to recreate these mappings */ | |
314e51b9 KK |
570 | vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTCOPY | |
571 | VM_DONTEXPAND | VM_DONTDUMP; | |
1c5de193 JF |
572 | vma->vm_ops = &privcmd_vm_ops; |
573 | vma->vm_private_data = NULL; | |
574 | ||
575 | return 0; | |
576 | } | |
577 | ||
a5deabe0 ALC |
578 | /* |
579 | * For MMAPBATCH*. This allows asserting the singleshot mapping | |
580 | * on a per pfn/pte basis. Mapping calls that fail with ENOENT | |
581 | * can be then retried until success. | |
582 | */ | |
583 | static int is_mapped_fn(pte_t *pte, struct page *pmd_page, | |
584 | unsigned long addr, void *data) | |
585 | { | |
586 | return pte_none(*pte) ? 0 : -EBUSY; | |
587 | } | |
588 | ||
589 | static int privcmd_vma_range_is_mapped( | |
590 | struct vm_area_struct *vma, | |
591 | unsigned long addr, | |
592 | unsigned long nr_pages) | |
1c5de193 | 593 | { |
a5deabe0 ALC |
594 | return apply_to_page_range(vma->vm_mm, addr, nr_pages << PAGE_SHIFT, |
595 | is_mapped_fn, NULL) != 0; | |
1c5de193 | 596 | } |
1c5de193 | 597 | |
d8414d3c BB |
598 | const struct file_operations xen_privcmd_fops = { |
599 | .owner = THIS_MODULE, | |
1c5de193 JF |
600 | .unlocked_ioctl = privcmd_ioctl, |
601 | .mmap = privcmd_mmap, | |
602 | }; | |
d8414d3c BB |
603 | EXPORT_SYMBOL_GPL(xen_privcmd_fops); |
604 | ||
605 | static struct miscdevice privcmd_dev = { | |
606 | .minor = MISC_DYNAMIC_MINOR, | |
607 | .name = "xen/privcmd", | |
608 | .fops = &xen_privcmd_fops, | |
609 | }; | |
610 | ||
611 | static int __init privcmd_init(void) | |
612 | { | |
613 | int err; | |
614 | ||
615 | if (!xen_domain()) | |
616 | return -ENODEV; | |
617 | ||
618 | err = misc_register(&privcmd_dev); | |
619 | if (err != 0) { | |
283c0972 | 620 | pr_err("Could not register Xen privcmd device\n"); |
d8414d3c BB |
621 | return err; |
622 | } | |
623 | return 0; | |
624 | } | |
625 | ||
626 | static void __exit privcmd_exit(void) | |
627 | { | |
628 | misc_deregister(&privcmd_dev); | |
629 | } | |
630 | ||
631 | module_init(privcmd_init); | |
632 | module_exit(privcmd_exit); |