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