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73572984 JA |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <linux/kernel.h> | |
3 | #include <linux/errno.h> | |
4 | #include <linux/fs.h> | |
5 | #include <linux/file.h> | |
6 | #include <linux/mm.h> | |
7 | #include <linux/slab.h> | |
8 | #include <linux/nospec.h> | |
9 | #include <linux/hugetlb.h> | |
10 | #include <linux/compat.h> | |
11 | #include <linux/io_uring.h> | |
12 | ||
13 | #include <uapi/linux/io_uring.h> | |
14 | ||
73572984 JA |
15 | #include "io_uring.h" |
16 | #include "openclose.h" | |
17 | #include "rsrc.h" | |
492dddb4 | 18 | #include "notif.h" |
73572984 JA |
19 | |
20 | struct io_rsrc_update { | |
21 | struct file *file; | |
22 | u64 arg; | |
23 | u32 nr_args; | |
24 | u32 offset; | |
4379d5f1 | 25 | int type; |
73572984 JA |
26 | }; |
27 | ||
28 | static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, | |
29 | struct io_mapped_ubuf **pimu, | |
30 | struct page **last_hpage); | |
31 | ||
32 | #define IO_RSRC_REF_BATCH 100 | |
33 | ||
34 | /* only define max */ | |
35 | #define IORING_MAX_FIXED_FILES (1U << 20) | |
36 | #define IORING_MAX_REG_BUFFERS (1U << 14) | |
37 | ||
38 | void io_rsrc_refs_drop(struct io_ring_ctx *ctx) | |
39 | __must_hold(&ctx->uring_lock) | |
40 | { | |
41 | if (ctx->rsrc_cached_refs) { | |
42 | io_rsrc_put_node(ctx->rsrc_node, ctx->rsrc_cached_refs); | |
43 | ctx->rsrc_cached_refs = 0; | |
44 | } | |
45 | } | |
46 | ||
6a9ce66f | 47 | int __io_account_mem(struct user_struct *user, unsigned long nr_pages) |
73572984 JA |
48 | { |
49 | unsigned long page_limit, cur_pages, new_pages; | |
50 | ||
6a9ce66f PB |
51 | if (!nr_pages) |
52 | return 0; | |
53 | ||
73572984 JA |
54 | /* Don't allow more pages than we can safely lock */ |
55 | page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; | |
56 | ||
4ccc6db0 | 57 | cur_pages = atomic_long_read(&user->locked_vm); |
73572984 | 58 | do { |
73572984 JA |
59 | new_pages = cur_pages + nr_pages; |
60 | if (new_pages > page_limit) | |
61 | return -ENOMEM; | |
4ccc6db0 UB |
62 | } while (!atomic_long_try_cmpxchg(&user->locked_vm, |
63 | &cur_pages, new_pages)); | |
73572984 JA |
64 | return 0; |
65 | } | |
66 | ||
67 | static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) | |
68 | { | |
69 | if (ctx->user) | |
70 | __io_unaccount_mem(ctx->user, nr_pages); | |
71 | ||
72 | if (ctx->mm_account) | |
73 | atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm); | |
74 | } | |
75 | ||
76 | static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) | |
77 | { | |
78 | int ret; | |
79 | ||
80 | if (ctx->user) { | |
81 | ret = __io_account_mem(ctx->user, nr_pages); | |
82 | if (ret) | |
83 | return ret; | |
84 | } | |
85 | ||
86 | if (ctx->mm_account) | |
87 | atomic64_add(nr_pages, &ctx->mm_account->pinned_vm); | |
88 | ||
89 | return 0; | |
90 | } | |
91 | ||
92 | static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst, | |
93 | void __user *arg, unsigned index) | |
94 | { | |
95 | struct iovec __user *src; | |
96 | ||
97 | #ifdef CONFIG_COMPAT | |
98 | if (ctx->compat) { | |
99 | struct compat_iovec __user *ciovs; | |
100 | struct compat_iovec ciov; | |
101 | ||
102 | ciovs = (struct compat_iovec __user *) arg; | |
103 | if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov))) | |
104 | return -EFAULT; | |
105 | ||
106 | dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base); | |
107 | dst->iov_len = ciov.iov_len; | |
108 | return 0; | |
109 | } | |
110 | #endif | |
111 | src = (struct iovec __user *) arg; | |
112 | if (copy_from_user(dst, &src[index], sizeof(*dst))) | |
113 | return -EFAULT; | |
114 | return 0; | |
115 | } | |
116 | ||
117 | static int io_buffer_validate(struct iovec *iov) | |
118 | { | |
119 | unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1); | |
120 | ||
121 | /* | |
122 | * Don't impose further limits on the size and buffer | |
123 | * constraints here, we'll -EINVAL later when IO is | |
124 | * submitted if they are wrong. | |
125 | */ | |
126 | if (!iov->iov_base) | |
127 | return iov->iov_len ? -EFAULT : 0; | |
128 | if (!iov->iov_len) | |
129 | return -EFAULT; | |
130 | ||
131 | /* arbitrary limit, but we need something */ | |
132 | if (iov->iov_len > SZ_1G) | |
133 | return -EFAULT; | |
134 | ||
135 | if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp)) | |
136 | return -EOVERFLOW; | |
137 | ||
138 | return 0; | |
139 | } | |
140 | ||
141 | static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot) | |
142 | { | |
143 | struct io_mapped_ubuf *imu = *slot; | |
144 | unsigned int i; | |
145 | ||
146 | if (imu != ctx->dummy_ubuf) { | |
147 | for (i = 0; i < imu->nr_bvecs; i++) | |
148 | unpin_user_page(imu->bvec[i].bv_page); | |
149 | if (imu->acct_pages) | |
150 | io_unaccount_mem(ctx, imu->acct_pages); | |
151 | kvfree(imu); | |
152 | } | |
153 | *slot = NULL; | |
154 | } | |
155 | ||
156 | void io_rsrc_refs_refill(struct io_ring_ctx *ctx) | |
157 | __must_hold(&ctx->uring_lock) | |
158 | { | |
159 | ctx->rsrc_cached_refs += IO_RSRC_REF_BATCH; | |
160 | percpu_ref_get_many(&ctx->rsrc_node->refs, IO_RSRC_REF_BATCH); | |
161 | } | |
162 | ||
163 | static void __io_rsrc_put_work(struct io_rsrc_node *ref_node) | |
164 | { | |
165 | struct io_rsrc_data *rsrc_data = ref_node->rsrc_data; | |
166 | struct io_ring_ctx *ctx = rsrc_data->ctx; | |
167 | struct io_rsrc_put *prsrc, *tmp; | |
168 | ||
169 | list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) { | |
170 | list_del(&prsrc->list); | |
171 | ||
172 | if (prsrc->tag) { | |
d245bca6 | 173 | if (ctx->flags & IORING_SETUP_IOPOLL) { |
73572984 | 174 | mutex_lock(&ctx->uring_lock); |
52120f0f | 175 | io_post_aux_cqe(ctx, prsrc->tag, 0, 0, true); |
73572984 | 176 | mutex_unlock(&ctx->uring_lock); |
d245bca6 | 177 | } else { |
52120f0f | 178 | io_post_aux_cqe(ctx, prsrc->tag, 0, 0, true); |
d245bca6 | 179 | } |
73572984 JA |
180 | } |
181 | ||
182 | rsrc_data->do_put(ctx, prsrc); | |
183 | kfree(prsrc); | |
184 | } | |
185 | ||
186 | io_rsrc_node_destroy(ref_node); | |
187 | if (atomic_dec_and_test(&rsrc_data->refs)) | |
188 | complete(&rsrc_data->done); | |
189 | } | |
190 | ||
191 | void io_rsrc_put_work(struct work_struct *work) | |
192 | { | |
193 | struct io_ring_ctx *ctx; | |
194 | struct llist_node *node; | |
195 | ||
196 | ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work); | |
197 | node = llist_del_all(&ctx->rsrc_put_llist); | |
198 | ||
199 | while (node) { | |
200 | struct io_rsrc_node *ref_node; | |
201 | struct llist_node *next = node->next; | |
202 | ||
203 | ref_node = llist_entry(node, struct io_rsrc_node, llist); | |
204 | __io_rsrc_put_work(ref_node); | |
205 | node = next; | |
206 | } | |
207 | } | |
208 | ||
209 | void io_wait_rsrc_data(struct io_rsrc_data *data) | |
210 | { | |
211 | if (data && !atomic_dec_and_test(&data->refs)) | |
212 | wait_for_completion(&data->done); | |
213 | } | |
214 | ||
215 | void io_rsrc_node_destroy(struct io_rsrc_node *ref_node) | |
216 | { | |
217 | percpu_ref_exit(&ref_node->refs); | |
218 | kfree(ref_node); | |
219 | } | |
220 | ||
221 | static __cold void io_rsrc_node_ref_zero(struct percpu_ref *ref) | |
222 | { | |
223 | struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs); | |
224 | struct io_ring_ctx *ctx = node->rsrc_data->ctx; | |
225 | unsigned long flags; | |
226 | bool first_add = false; | |
227 | unsigned long delay = HZ; | |
228 | ||
229 | spin_lock_irqsave(&ctx->rsrc_ref_lock, flags); | |
230 | node->done = true; | |
231 | ||
232 | /* if we are mid-quiesce then do not delay */ | |
233 | if (node->rsrc_data->quiesce) | |
234 | delay = 0; | |
235 | ||
236 | while (!list_empty(&ctx->rsrc_ref_list)) { | |
237 | node = list_first_entry(&ctx->rsrc_ref_list, | |
238 | struct io_rsrc_node, node); | |
239 | /* recycle ref nodes in order */ | |
240 | if (!node->done) | |
241 | break; | |
242 | list_del(&node->node); | |
243 | first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist); | |
244 | } | |
245 | spin_unlock_irqrestore(&ctx->rsrc_ref_lock, flags); | |
246 | ||
247 | if (first_add) | |
248 | mod_delayed_work(system_wq, &ctx->rsrc_put_work, delay); | |
249 | } | |
250 | ||
251 | static struct io_rsrc_node *io_rsrc_node_alloc(void) | |
252 | { | |
253 | struct io_rsrc_node *ref_node; | |
254 | ||
255 | ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL); | |
256 | if (!ref_node) | |
257 | return NULL; | |
258 | ||
259 | if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero, | |
260 | 0, GFP_KERNEL)) { | |
261 | kfree(ref_node); | |
262 | return NULL; | |
263 | } | |
264 | INIT_LIST_HEAD(&ref_node->node); | |
265 | INIT_LIST_HEAD(&ref_node->rsrc_list); | |
266 | ref_node->done = false; | |
267 | return ref_node; | |
268 | } | |
269 | ||
270 | void io_rsrc_node_switch(struct io_ring_ctx *ctx, | |
271 | struct io_rsrc_data *data_to_kill) | |
272 | __must_hold(&ctx->uring_lock) | |
273 | { | |
274 | WARN_ON_ONCE(!ctx->rsrc_backup_node); | |
275 | WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node); | |
276 | ||
277 | io_rsrc_refs_drop(ctx); | |
278 | ||
279 | if (data_to_kill) { | |
280 | struct io_rsrc_node *rsrc_node = ctx->rsrc_node; | |
281 | ||
282 | rsrc_node->rsrc_data = data_to_kill; | |
283 | spin_lock_irq(&ctx->rsrc_ref_lock); | |
284 | list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list); | |
285 | spin_unlock_irq(&ctx->rsrc_ref_lock); | |
286 | ||
287 | atomic_inc(&data_to_kill->refs); | |
288 | percpu_ref_kill(&rsrc_node->refs); | |
289 | ctx->rsrc_node = NULL; | |
290 | } | |
291 | ||
292 | if (!ctx->rsrc_node) { | |
293 | ctx->rsrc_node = ctx->rsrc_backup_node; | |
294 | ctx->rsrc_backup_node = NULL; | |
295 | } | |
296 | } | |
297 | ||
298 | int io_rsrc_node_switch_start(struct io_ring_ctx *ctx) | |
299 | { | |
300 | if (ctx->rsrc_backup_node) | |
301 | return 0; | |
302 | ctx->rsrc_backup_node = io_rsrc_node_alloc(); | |
303 | return ctx->rsrc_backup_node ? 0 : -ENOMEM; | |
304 | } | |
305 | ||
306 | __cold static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, | |
307 | struct io_ring_ctx *ctx) | |
308 | { | |
309 | int ret; | |
310 | ||
311 | /* As we may drop ->uring_lock, other task may have started quiesce */ | |
312 | if (data->quiesce) | |
313 | return -ENXIO; | |
314 | ||
315 | data->quiesce = true; | |
316 | do { | |
317 | ret = io_rsrc_node_switch_start(ctx); | |
318 | if (ret) | |
319 | break; | |
320 | io_rsrc_node_switch(ctx, data); | |
321 | ||
322 | /* kill initial ref, already quiesced if zero */ | |
323 | if (atomic_dec_and_test(&data->refs)) | |
324 | break; | |
325 | mutex_unlock(&ctx->uring_lock); | |
326 | flush_delayed_work(&ctx->rsrc_put_work); | |
327 | ret = wait_for_completion_interruptible(&data->done); | |
328 | if (!ret) { | |
329 | mutex_lock(&ctx->uring_lock); | |
330 | if (atomic_read(&data->refs) > 0) { | |
331 | /* | |
332 | * it has been revived by another thread while | |
333 | * we were unlocked | |
334 | */ | |
335 | mutex_unlock(&ctx->uring_lock); | |
336 | } else { | |
337 | break; | |
338 | } | |
339 | } | |
340 | ||
341 | atomic_inc(&data->refs); | |
342 | /* wait for all works potentially completing data->done */ | |
343 | flush_delayed_work(&ctx->rsrc_put_work); | |
344 | reinit_completion(&data->done); | |
345 | ||
346 | ret = io_run_task_work_sig(); | |
347 | mutex_lock(&ctx->uring_lock); | |
348 | } while (ret >= 0); | |
349 | data->quiesce = false; | |
350 | ||
351 | return ret; | |
352 | } | |
353 | ||
354 | static void io_free_page_table(void **table, size_t size) | |
355 | { | |
356 | unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); | |
357 | ||
358 | for (i = 0; i < nr_tables; i++) | |
359 | kfree(table[i]); | |
360 | kfree(table); | |
361 | } | |
362 | ||
363 | static void io_rsrc_data_free(struct io_rsrc_data *data) | |
364 | { | |
365 | size_t size = data->nr * sizeof(data->tags[0][0]); | |
366 | ||
367 | if (data->tags) | |
368 | io_free_page_table((void **)data->tags, size); | |
369 | kfree(data); | |
370 | } | |
371 | ||
372 | static __cold void **io_alloc_page_table(size_t size) | |
373 | { | |
374 | unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); | |
375 | size_t init_size = size; | |
376 | void **table; | |
377 | ||
378 | table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT); | |
379 | if (!table) | |
380 | return NULL; | |
381 | ||
382 | for (i = 0; i < nr_tables; i++) { | |
383 | unsigned int this_size = min_t(size_t, size, PAGE_SIZE); | |
384 | ||
385 | table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT); | |
386 | if (!table[i]) { | |
387 | io_free_page_table(table, init_size); | |
388 | return NULL; | |
389 | } | |
390 | size -= this_size; | |
391 | } | |
392 | return table; | |
393 | } | |
394 | ||
395 | __cold static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, | |
396 | rsrc_put_fn *do_put, u64 __user *utags, | |
397 | unsigned nr, struct io_rsrc_data **pdata) | |
398 | { | |
399 | struct io_rsrc_data *data; | |
400 | int ret = -ENOMEM; | |
401 | unsigned i; | |
402 | ||
403 | data = kzalloc(sizeof(*data), GFP_KERNEL); | |
404 | if (!data) | |
405 | return -ENOMEM; | |
406 | data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0])); | |
407 | if (!data->tags) { | |
408 | kfree(data); | |
409 | return -ENOMEM; | |
410 | } | |
411 | ||
412 | data->nr = nr; | |
413 | data->ctx = ctx; | |
414 | data->do_put = do_put; | |
415 | if (utags) { | |
416 | ret = -EFAULT; | |
417 | for (i = 0; i < nr; i++) { | |
418 | u64 *tag_slot = io_get_tag_slot(data, i); | |
419 | ||
420 | if (copy_from_user(tag_slot, &utags[i], | |
421 | sizeof(*tag_slot))) | |
422 | goto fail; | |
423 | } | |
424 | } | |
425 | ||
426 | atomic_set(&data->refs, 1); | |
427 | init_completion(&data->done); | |
428 | *pdata = data; | |
429 | return 0; | |
430 | fail: | |
431 | io_rsrc_data_free(data); | |
432 | return ret; | |
433 | } | |
434 | ||
435 | static int __io_sqe_files_update(struct io_ring_ctx *ctx, | |
436 | struct io_uring_rsrc_update2 *up, | |
437 | unsigned nr_args) | |
438 | { | |
439 | u64 __user *tags = u64_to_user_ptr(up->tags); | |
440 | __s32 __user *fds = u64_to_user_ptr(up->data); | |
441 | struct io_rsrc_data *data = ctx->file_data; | |
442 | struct io_fixed_file *file_slot; | |
443 | struct file *file; | |
444 | int fd, i, err = 0; | |
445 | unsigned int done; | |
446 | bool needs_switch = false; | |
447 | ||
448 | if (!ctx->file_data) | |
449 | return -ENXIO; | |
450 | if (up->offset + nr_args > ctx->nr_user_files) | |
451 | return -EINVAL; | |
452 | ||
453 | for (done = 0; done < nr_args; done++) { | |
454 | u64 tag = 0; | |
455 | ||
456 | if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) || | |
457 | copy_from_user(&fd, &fds[done], sizeof(fd))) { | |
458 | err = -EFAULT; | |
459 | break; | |
460 | } | |
461 | if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) { | |
462 | err = -EINVAL; | |
463 | break; | |
464 | } | |
465 | if (fd == IORING_REGISTER_FILES_SKIP) | |
466 | continue; | |
467 | ||
468 | i = array_index_nospec(up->offset + done, ctx->nr_user_files); | |
469 | file_slot = io_fixed_file_slot(&ctx->file_table, i); | |
470 | ||
471 | if (file_slot->file_ptr) { | |
472 | file = (struct file *)(file_slot->file_ptr & FFS_MASK); | |
473 | err = io_queue_rsrc_removal(data, i, ctx->rsrc_node, file); | |
474 | if (err) | |
475 | break; | |
476 | file_slot->file_ptr = 0; | |
477 | io_file_bitmap_clear(&ctx->file_table, i); | |
478 | needs_switch = true; | |
479 | } | |
480 | if (fd != -1) { | |
481 | file = fget(fd); | |
482 | if (!file) { | |
483 | err = -EBADF; | |
484 | break; | |
485 | } | |
486 | /* | |
487 | * Don't allow io_uring instances to be registered. If | |
488 | * UNIX isn't enabled, then this causes a reference | |
489 | * cycle and this instance can never get freed. If UNIX | |
490 | * is enabled we'll handle it just fine, but there's | |
491 | * still no point in allowing a ring fd as it doesn't | |
492 | * support regular read/write anyway. | |
493 | */ | |
494 | if (io_is_uring_fops(file)) { | |
495 | fput(file); | |
496 | err = -EBADF; | |
497 | break; | |
498 | } | |
499 | err = io_scm_file_account(ctx, file); | |
500 | if (err) { | |
501 | fput(file); | |
502 | break; | |
503 | } | |
504 | *io_get_tag_slot(data, i) = tag; | |
505 | io_fixed_file_set(file_slot, file); | |
506 | io_file_bitmap_set(&ctx->file_table, i); | |
507 | } | |
508 | } | |
509 | ||
510 | if (needs_switch) | |
511 | io_rsrc_node_switch(ctx, data); | |
512 | return done ? done : err; | |
513 | } | |
514 | ||
515 | static int __io_sqe_buffers_update(struct io_ring_ctx *ctx, | |
516 | struct io_uring_rsrc_update2 *up, | |
517 | unsigned int nr_args) | |
518 | { | |
519 | u64 __user *tags = u64_to_user_ptr(up->tags); | |
520 | struct iovec iov, __user *iovs = u64_to_user_ptr(up->data); | |
521 | struct page *last_hpage = NULL; | |
522 | bool needs_switch = false; | |
523 | __u32 done; | |
524 | int i, err; | |
525 | ||
526 | if (!ctx->buf_data) | |
527 | return -ENXIO; | |
528 | if (up->offset + nr_args > ctx->nr_user_bufs) | |
529 | return -EINVAL; | |
530 | ||
531 | for (done = 0; done < nr_args; done++) { | |
532 | struct io_mapped_ubuf *imu; | |
533 | int offset = up->offset + done; | |
534 | u64 tag = 0; | |
535 | ||
536 | err = io_copy_iov(ctx, &iov, iovs, done); | |
537 | if (err) | |
538 | break; | |
539 | if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) { | |
540 | err = -EFAULT; | |
541 | break; | |
542 | } | |
543 | err = io_buffer_validate(&iov); | |
544 | if (err) | |
545 | break; | |
546 | if (!iov.iov_base && tag) { | |
547 | err = -EINVAL; | |
548 | break; | |
549 | } | |
550 | err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage); | |
551 | if (err) | |
552 | break; | |
553 | ||
554 | i = array_index_nospec(offset, ctx->nr_user_bufs); | |
555 | if (ctx->user_bufs[i] != ctx->dummy_ubuf) { | |
556 | err = io_queue_rsrc_removal(ctx->buf_data, i, | |
557 | ctx->rsrc_node, ctx->user_bufs[i]); | |
558 | if (unlikely(err)) { | |
559 | io_buffer_unmap(ctx, &imu); | |
560 | break; | |
561 | } | |
5ff4fdff | 562 | ctx->user_bufs[i] = ctx->dummy_ubuf; |
73572984 JA |
563 | needs_switch = true; |
564 | } | |
565 | ||
566 | ctx->user_bufs[i] = imu; | |
567 | *io_get_tag_slot(ctx->buf_data, offset) = tag; | |
568 | } | |
569 | ||
570 | if (needs_switch) | |
571 | io_rsrc_node_switch(ctx, ctx->buf_data); | |
572 | return done ? done : err; | |
573 | } | |
574 | ||
575 | static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type, | |
576 | struct io_uring_rsrc_update2 *up, | |
577 | unsigned nr_args) | |
578 | { | |
579 | __u32 tmp; | |
580 | int err; | |
581 | ||
582 | if (check_add_overflow(up->offset, nr_args, &tmp)) | |
583 | return -EOVERFLOW; | |
584 | err = io_rsrc_node_switch_start(ctx); | |
585 | if (err) | |
586 | return err; | |
587 | ||
588 | switch (type) { | |
589 | case IORING_RSRC_FILE: | |
590 | return __io_sqe_files_update(ctx, up, nr_args); | |
591 | case IORING_RSRC_BUFFER: | |
592 | return __io_sqe_buffers_update(ctx, up, nr_args); | |
593 | } | |
594 | return -EINVAL; | |
595 | } | |
596 | ||
597 | int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg, | |
598 | unsigned nr_args) | |
599 | { | |
600 | struct io_uring_rsrc_update2 up; | |
601 | ||
602 | if (!nr_args) | |
603 | return -EINVAL; | |
604 | memset(&up, 0, sizeof(up)); | |
605 | if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update))) | |
606 | return -EFAULT; | |
607 | if (up.resv || up.resv2) | |
608 | return -EINVAL; | |
609 | return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args); | |
610 | } | |
611 | ||
612 | int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg, | |
613 | unsigned size, unsigned type) | |
614 | { | |
615 | struct io_uring_rsrc_update2 up; | |
616 | ||
617 | if (size != sizeof(up)) | |
618 | return -EINVAL; | |
619 | if (copy_from_user(&up, arg, sizeof(up))) | |
620 | return -EFAULT; | |
621 | if (!up.nr || up.resv || up.resv2) | |
622 | return -EINVAL; | |
623 | return __io_register_rsrc_update(ctx, type, &up, up.nr); | |
624 | } | |
625 | ||
626 | __cold int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg, | |
627 | unsigned int size, unsigned int type) | |
628 | { | |
629 | struct io_uring_rsrc_register rr; | |
630 | ||
631 | /* keep it extendible */ | |
632 | if (size != sizeof(rr)) | |
633 | return -EINVAL; | |
634 | ||
635 | memset(&rr, 0, sizeof(rr)); | |
636 | if (copy_from_user(&rr, arg, size)) | |
637 | return -EFAULT; | |
638 | if (!rr.nr || rr.resv2) | |
639 | return -EINVAL; | |
640 | if (rr.flags & ~IORING_RSRC_REGISTER_SPARSE) | |
641 | return -EINVAL; | |
642 | ||
643 | switch (type) { | |
644 | case IORING_RSRC_FILE: | |
645 | if (rr.flags & IORING_RSRC_REGISTER_SPARSE && rr.data) | |
646 | break; | |
647 | return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data), | |
648 | rr.nr, u64_to_user_ptr(rr.tags)); | |
649 | case IORING_RSRC_BUFFER: | |
650 | if (rr.flags & IORING_RSRC_REGISTER_SPARSE && rr.data) | |
651 | break; | |
652 | return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data), | |
653 | rr.nr, u64_to_user_ptr(rr.tags)); | |
654 | } | |
655 | return -EINVAL; | |
656 | } | |
657 | ||
4379d5f1 | 658 | int io_rsrc_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
73572984 | 659 | { |
f2ccb5ae | 660 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
73572984 JA |
661 | |
662 | if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT))) | |
663 | return -EINVAL; | |
664 | if (sqe->rw_flags || sqe->splice_fd_in) | |
665 | return -EINVAL; | |
666 | ||
667 | up->offset = READ_ONCE(sqe->off); | |
668 | up->nr_args = READ_ONCE(sqe->len); | |
669 | if (!up->nr_args) | |
670 | return -EINVAL; | |
671 | up->arg = READ_ONCE(sqe->addr); | |
4379d5f1 | 672 | up->type = READ_ONCE(sqe->ioprio); |
73572984 JA |
673 | return 0; |
674 | } | |
675 | ||
676 | static int io_files_update_with_index_alloc(struct io_kiocb *req, | |
677 | unsigned int issue_flags) | |
678 | { | |
f2ccb5ae | 679 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
73572984 JA |
680 | __s32 __user *fds = u64_to_user_ptr(up->arg); |
681 | unsigned int done; | |
682 | struct file *file; | |
683 | int ret, fd; | |
684 | ||
685 | if (!req->ctx->file_data) | |
686 | return -ENXIO; | |
687 | ||
688 | for (done = 0; done < up->nr_args; done++) { | |
689 | if (copy_from_user(&fd, &fds[done], sizeof(fd))) { | |
690 | ret = -EFAULT; | |
691 | break; | |
692 | } | |
693 | ||
694 | file = fget(fd); | |
695 | if (!file) { | |
696 | ret = -EBADF; | |
697 | break; | |
698 | } | |
699 | ret = io_fixed_fd_install(req, issue_flags, file, | |
700 | IORING_FILE_INDEX_ALLOC); | |
701 | if (ret < 0) | |
702 | break; | |
703 | if (copy_to_user(&fds[done], &ret, sizeof(ret))) { | |
f110ed84 | 704 | __io_close_fixed(req->ctx, issue_flags, ret); |
73572984 JA |
705 | ret = -EFAULT; |
706 | break; | |
707 | } | |
708 | } | |
709 | ||
710 | if (done) | |
711 | return done; | |
712 | return ret; | |
713 | } | |
714 | ||
4379d5f1 | 715 | static int io_files_update(struct io_kiocb *req, unsigned int issue_flags) |
73572984 | 716 | { |
f2ccb5ae | 717 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
73572984 JA |
718 | struct io_ring_ctx *ctx = req->ctx; |
719 | struct io_uring_rsrc_update2 up2; | |
720 | int ret; | |
721 | ||
722 | up2.offset = up->offset; | |
723 | up2.data = up->arg; | |
724 | up2.nr = 0; | |
725 | up2.tags = 0; | |
726 | up2.resv = 0; | |
727 | up2.resv2 = 0; | |
728 | ||
729 | if (up->offset == IORING_FILE_INDEX_ALLOC) { | |
730 | ret = io_files_update_with_index_alloc(req, issue_flags); | |
731 | } else { | |
732 | io_ring_submit_lock(ctx, issue_flags); | |
733 | ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE, | |
734 | &up2, up->nr_args); | |
735 | io_ring_submit_unlock(ctx, issue_flags); | |
736 | } | |
737 | ||
738 | if (ret < 0) | |
739 | req_set_fail(req); | |
740 | io_req_set_res(req, ret, 0); | |
741 | return IOU_OK; | |
742 | } | |
743 | ||
492dddb4 PB |
744 | static int io_notif_update(struct io_kiocb *req, unsigned int issue_flags) |
745 | { | |
f2ccb5ae | 746 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
492dddb4 PB |
747 | struct io_ring_ctx *ctx = req->ctx; |
748 | unsigned len = up->nr_args; | |
749 | unsigned idx_end, idx = up->offset; | |
750 | int ret = 0; | |
751 | ||
752 | io_ring_submit_lock(ctx, issue_flags); | |
753 | if (unlikely(check_add_overflow(idx, len, &idx_end))) { | |
754 | ret = -EOVERFLOW; | |
755 | goto out; | |
756 | } | |
757 | if (unlikely(idx_end > ctx->nr_notif_slots)) { | |
758 | ret = -EINVAL; | |
759 | goto out; | |
760 | } | |
761 | ||
762 | for (; idx < idx_end; idx++) { | |
763 | struct io_notif_slot *slot = &ctx->notif_slots[idx]; | |
764 | ||
765 | if (!slot->notif) | |
766 | continue; | |
767 | if (up->arg) | |
768 | slot->tag = up->arg; | |
769 | io_notif_slot_flush_submit(slot, issue_flags); | |
770 | } | |
771 | out: | |
772 | io_ring_submit_unlock(ctx, issue_flags); | |
773 | if (ret < 0) | |
774 | req_set_fail(req); | |
775 | io_req_set_res(req, ret, 0); | |
776 | return IOU_OK; | |
777 | } | |
778 | ||
4379d5f1 PB |
779 | int io_rsrc_update(struct io_kiocb *req, unsigned int issue_flags) |
780 | { | |
f2ccb5ae | 781 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
4379d5f1 PB |
782 | |
783 | switch (up->type) { | |
784 | case IORING_RSRC_UPDATE_FILES: | |
785 | return io_files_update(req, issue_flags); | |
492dddb4 PB |
786 | case IORING_RSRC_UPDATE_NOTIF: |
787 | return io_notif_update(req, issue_flags); | |
4379d5f1 PB |
788 | } |
789 | return -EINVAL; | |
790 | } | |
791 | ||
73572984 JA |
792 | int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx, |
793 | struct io_rsrc_node *node, void *rsrc) | |
794 | { | |
795 | u64 *tag_slot = io_get_tag_slot(data, idx); | |
796 | struct io_rsrc_put *prsrc; | |
797 | ||
798 | prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL); | |
799 | if (!prsrc) | |
800 | return -ENOMEM; | |
801 | ||
802 | prsrc->tag = *tag_slot; | |
803 | *tag_slot = 0; | |
804 | prsrc->rsrc = rsrc; | |
805 | list_add(&prsrc->list, &node->rsrc_list); | |
806 | return 0; | |
807 | } | |
808 | ||
809 | void __io_sqe_files_unregister(struct io_ring_ctx *ctx) | |
810 | { | |
811 | #if !defined(IO_URING_SCM_ALL) | |
812 | int i; | |
813 | ||
814 | for (i = 0; i < ctx->nr_user_files; i++) { | |
815 | struct file *file = io_file_from_index(&ctx->file_table, i); | |
816 | ||
817 | if (!file) | |
818 | continue; | |
819 | if (io_fixed_file_slot(&ctx->file_table, i)->file_ptr & FFS_SCM) | |
820 | continue; | |
821 | io_file_bitmap_clear(&ctx->file_table, i); | |
822 | fput(file); | |
823 | } | |
824 | #endif | |
825 | ||
826 | #if defined(CONFIG_UNIX) | |
827 | if (ctx->ring_sock) { | |
828 | struct sock *sock = ctx->ring_sock->sk; | |
829 | struct sk_buff *skb; | |
830 | ||
831 | while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL) | |
832 | kfree_skb(skb); | |
833 | } | |
834 | #endif | |
835 | io_free_file_tables(&ctx->file_table); | |
836 | io_rsrc_data_free(ctx->file_data); | |
837 | ctx->file_data = NULL; | |
838 | ctx->nr_user_files = 0; | |
839 | } | |
840 | ||
841 | int io_sqe_files_unregister(struct io_ring_ctx *ctx) | |
842 | { | |
843 | unsigned nr = ctx->nr_user_files; | |
844 | int ret; | |
845 | ||
846 | if (!ctx->file_data) | |
847 | return -ENXIO; | |
848 | ||
849 | /* | |
850 | * Quiesce may unlock ->uring_lock, and while it's not held | |
851 | * prevent new requests using the table. | |
852 | */ | |
853 | ctx->nr_user_files = 0; | |
854 | ret = io_rsrc_ref_quiesce(ctx->file_data, ctx); | |
855 | ctx->nr_user_files = nr; | |
856 | if (!ret) | |
857 | __io_sqe_files_unregister(ctx); | |
858 | return ret; | |
859 | } | |
860 | ||
861 | /* | |
862 | * Ensure the UNIX gc is aware of our file set, so we are certain that | |
863 | * the io_uring can be safely unregistered on process exit, even if we have | |
864 | * loops in the file referencing. We account only files that can hold other | |
865 | * files because otherwise they can't form a loop and so are not interesting | |
866 | * for GC. | |
867 | */ | |
868 | int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file) | |
869 | { | |
870 | #if defined(CONFIG_UNIX) | |
871 | struct sock *sk = ctx->ring_sock->sk; | |
872 | struct sk_buff_head *head = &sk->sk_receive_queue; | |
873 | struct scm_fp_list *fpl; | |
874 | struct sk_buff *skb; | |
875 | ||
876 | if (likely(!io_file_need_scm(file))) | |
877 | return 0; | |
878 | ||
879 | /* | |
880 | * See if we can merge this file into an existing skb SCM_RIGHTS | |
881 | * file set. If there's no room, fall back to allocating a new skb | |
882 | * and filling it in. | |
883 | */ | |
884 | spin_lock_irq(&head->lock); | |
885 | skb = skb_peek(head); | |
886 | if (skb && UNIXCB(skb).fp->count < SCM_MAX_FD) | |
887 | __skb_unlink(skb, head); | |
888 | else | |
889 | skb = NULL; | |
890 | spin_unlock_irq(&head->lock); | |
891 | ||
892 | if (!skb) { | |
893 | fpl = kzalloc(sizeof(*fpl), GFP_KERNEL); | |
894 | if (!fpl) | |
895 | return -ENOMEM; | |
896 | ||
897 | skb = alloc_skb(0, GFP_KERNEL); | |
898 | if (!skb) { | |
899 | kfree(fpl); | |
900 | return -ENOMEM; | |
901 | } | |
902 | ||
903 | fpl->user = get_uid(current_user()); | |
904 | fpl->max = SCM_MAX_FD; | |
905 | fpl->count = 0; | |
906 | ||
907 | UNIXCB(skb).fp = fpl; | |
908 | skb->sk = sk; | |
909 | skb->destructor = unix_destruct_scm; | |
910 | refcount_add(skb->truesize, &sk->sk_wmem_alloc); | |
911 | } | |
912 | ||
913 | fpl = UNIXCB(skb).fp; | |
914 | fpl->fp[fpl->count++] = get_file(file); | |
915 | unix_inflight(fpl->user, file); | |
916 | skb_queue_head(head, skb); | |
917 | fput(file); | |
918 | #endif | |
919 | return 0; | |
920 | } | |
921 | ||
922 | static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) | |
923 | { | |
924 | struct file *file = prsrc->file; | |
925 | #if defined(CONFIG_UNIX) | |
926 | struct sock *sock = ctx->ring_sock->sk; | |
927 | struct sk_buff_head list, *head = &sock->sk_receive_queue; | |
928 | struct sk_buff *skb; | |
929 | int i; | |
930 | ||
931 | if (!io_file_need_scm(file)) { | |
932 | fput(file); | |
933 | return; | |
934 | } | |
935 | ||
936 | __skb_queue_head_init(&list); | |
937 | ||
938 | /* | |
939 | * Find the skb that holds this file in its SCM_RIGHTS. When found, | |
940 | * remove this entry and rearrange the file array. | |
941 | */ | |
942 | skb = skb_dequeue(head); | |
943 | while (skb) { | |
944 | struct scm_fp_list *fp; | |
945 | ||
946 | fp = UNIXCB(skb).fp; | |
947 | for (i = 0; i < fp->count; i++) { | |
948 | int left; | |
949 | ||
950 | if (fp->fp[i] != file) | |
951 | continue; | |
952 | ||
953 | unix_notinflight(fp->user, fp->fp[i]); | |
954 | left = fp->count - 1 - i; | |
955 | if (left) { | |
956 | memmove(&fp->fp[i], &fp->fp[i + 1], | |
957 | left * sizeof(struct file *)); | |
958 | } | |
959 | fp->count--; | |
960 | if (!fp->count) { | |
961 | kfree_skb(skb); | |
962 | skb = NULL; | |
963 | } else { | |
964 | __skb_queue_tail(&list, skb); | |
965 | } | |
966 | fput(file); | |
967 | file = NULL; | |
968 | break; | |
969 | } | |
970 | ||
971 | if (!file) | |
972 | break; | |
973 | ||
974 | __skb_queue_tail(&list, skb); | |
975 | ||
976 | skb = skb_dequeue(head); | |
977 | } | |
978 | ||
979 | if (skb_peek(&list)) { | |
980 | spin_lock_irq(&head->lock); | |
981 | while ((skb = __skb_dequeue(&list)) != NULL) | |
982 | __skb_queue_tail(head, skb); | |
983 | spin_unlock_irq(&head->lock); | |
984 | } | |
985 | #else | |
986 | fput(file); | |
987 | #endif | |
988 | } | |
989 | ||
990 | int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, | |
991 | unsigned nr_args, u64 __user *tags) | |
992 | { | |
993 | __s32 __user *fds = (__s32 __user *) arg; | |
994 | struct file *file; | |
995 | int fd, ret; | |
996 | unsigned i; | |
997 | ||
998 | if (ctx->file_data) | |
999 | return -EBUSY; | |
1000 | if (!nr_args) | |
1001 | return -EINVAL; | |
1002 | if (nr_args > IORING_MAX_FIXED_FILES) | |
1003 | return -EMFILE; | |
1004 | if (nr_args > rlimit(RLIMIT_NOFILE)) | |
1005 | return -EMFILE; | |
1006 | ret = io_rsrc_node_switch_start(ctx); | |
1007 | if (ret) | |
1008 | return ret; | |
1009 | ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args, | |
1010 | &ctx->file_data); | |
1011 | if (ret) | |
1012 | return ret; | |
1013 | ||
1014 | if (!io_alloc_file_tables(&ctx->file_table, nr_args)) { | |
1015 | io_rsrc_data_free(ctx->file_data); | |
1016 | ctx->file_data = NULL; | |
1017 | return -ENOMEM; | |
1018 | } | |
1019 | ||
1020 | for (i = 0; i < nr_args; i++, ctx->nr_user_files++) { | |
1021 | struct io_fixed_file *file_slot; | |
1022 | ||
1023 | if (fds && copy_from_user(&fd, &fds[i], sizeof(fd))) { | |
1024 | ret = -EFAULT; | |
1025 | goto fail; | |
1026 | } | |
1027 | /* allow sparse sets */ | |
1028 | if (!fds || fd == -1) { | |
1029 | ret = -EINVAL; | |
1030 | if (unlikely(*io_get_tag_slot(ctx->file_data, i))) | |
1031 | goto fail; | |
1032 | continue; | |
1033 | } | |
1034 | ||
1035 | file = fget(fd); | |
1036 | ret = -EBADF; | |
1037 | if (unlikely(!file)) | |
1038 | goto fail; | |
1039 | ||
1040 | /* | |
1041 | * Don't allow io_uring instances to be registered. If UNIX | |
1042 | * isn't enabled, then this causes a reference cycle and this | |
1043 | * instance can never get freed. If UNIX is enabled we'll | |
1044 | * handle it just fine, but there's still no point in allowing | |
1045 | * a ring fd as it doesn't support regular read/write anyway. | |
1046 | */ | |
1047 | if (io_is_uring_fops(file)) { | |
1048 | fput(file); | |
1049 | goto fail; | |
1050 | } | |
1051 | ret = io_scm_file_account(ctx, file); | |
1052 | if (ret) { | |
1053 | fput(file); | |
1054 | goto fail; | |
1055 | } | |
1056 | file_slot = io_fixed_file_slot(&ctx->file_table, i); | |
1057 | io_fixed_file_set(file_slot, file); | |
1058 | io_file_bitmap_set(&ctx->file_table, i); | |
1059 | } | |
1060 | ||
6e73dffb PB |
1061 | /* default it to the whole table */ |
1062 | io_file_table_set_alloc_range(ctx, 0, ctx->nr_user_files); | |
73572984 JA |
1063 | io_rsrc_node_switch(ctx, NULL); |
1064 | return 0; | |
1065 | fail: | |
1066 | __io_sqe_files_unregister(ctx); | |
1067 | return ret; | |
1068 | } | |
1069 | ||
1070 | static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) | |
1071 | { | |
1072 | io_buffer_unmap(ctx, &prsrc->buf); | |
1073 | prsrc->buf = NULL; | |
1074 | } | |
1075 | ||
1076 | void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx) | |
1077 | { | |
1078 | unsigned int i; | |
1079 | ||
1080 | for (i = 0; i < ctx->nr_user_bufs; i++) | |
1081 | io_buffer_unmap(ctx, &ctx->user_bufs[i]); | |
1082 | kfree(ctx->user_bufs); | |
1083 | io_rsrc_data_free(ctx->buf_data); | |
1084 | ctx->user_bufs = NULL; | |
1085 | ctx->buf_data = NULL; | |
1086 | ctx->nr_user_bufs = 0; | |
1087 | } | |
1088 | ||
1089 | int io_sqe_buffers_unregister(struct io_ring_ctx *ctx) | |
1090 | { | |
1091 | unsigned nr = ctx->nr_user_bufs; | |
1092 | int ret; | |
1093 | ||
1094 | if (!ctx->buf_data) | |
1095 | return -ENXIO; | |
1096 | ||
1097 | /* | |
1098 | * Quiesce may unlock ->uring_lock, and while it's not held | |
1099 | * prevent new requests using the table. | |
1100 | */ | |
1101 | ctx->nr_user_bufs = 0; | |
1102 | ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx); | |
1103 | ctx->nr_user_bufs = nr; | |
1104 | if (!ret) | |
1105 | __io_sqe_buffers_unregister(ctx); | |
1106 | return ret; | |
1107 | } | |
1108 | ||
1109 | /* | |
1110 | * Not super efficient, but this is just a registration time. And we do cache | |
1111 | * the last compound head, so generally we'll only do a full search if we don't | |
1112 | * match that one. | |
1113 | * | |
1114 | * We check if the given compound head page has already been accounted, to | |
1115 | * avoid double accounting it. This allows us to account the full size of the | |
1116 | * page, not just the constituent pages of a huge page. | |
1117 | */ | |
1118 | static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages, | |
1119 | int nr_pages, struct page *hpage) | |
1120 | { | |
1121 | int i, j; | |
1122 | ||
1123 | /* check current page array */ | |
1124 | for (i = 0; i < nr_pages; i++) { | |
1125 | if (!PageCompound(pages[i])) | |
1126 | continue; | |
1127 | if (compound_head(pages[i]) == hpage) | |
1128 | return true; | |
1129 | } | |
1130 | ||
1131 | /* check previously registered pages */ | |
1132 | for (i = 0; i < ctx->nr_user_bufs; i++) { | |
1133 | struct io_mapped_ubuf *imu = ctx->user_bufs[i]; | |
1134 | ||
1135 | for (j = 0; j < imu->nr_bvecs; j++) { | |
1136 | if (!PageCompound(imu->bvec[j].bv_page)) | |
1137 | continue; | |
1138 | if (compound_head(imu->bvec[j].bv_page) == hpage) | |
1139 | return true; | |
1140 | } | |
1141 | } | |
1142 | ||
1143 | return false; | |
1144 | } | |
1145 | ||
1146 | static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages, | |
1147 | int nr_pages, struct io_mapped_ubuf *imu, | |
1148 | struct page **last_hpage) | |
1149 | { | |
1150 | int i, ret; | |
1151 | ||
1152 | imu->acct_pages = 0; | |
1153 | for (i = 0; i < nr_pages; i++) { | |
1154 | if (!PageCompound(pages[i])) { | |
1155 | imu->acct_pages++; | |
1156 | } else { | |
1157 | struct page *hpage; | |
1158 | ||
1159 | hpage = compound_head(pages[i]); | |
1160 | if (hpage == *last_hpage) | |
1161 | continue; | |
1162 | *last_hpage = hpage; | |
1163 | if (headpage_already_acct(ctx, pages, i, hpage)) | |
1164 | continue; | |
1165 | imu->acct_pages += page_size(hpage) >> PAGE_SHIFT; | |
1166 | } | |
1167 | } | |
1168 | ||
1169 | if (!imu->acct_pages) | |
1170 | return 0; | |
1171 | ||
1172 | ret = io_account_mem(ctx, imu->acct_pages); | |
1173 | if (ret) | |
1174 | imu->acct_pages = 0; | |
1175 | return ret; | |
1176 | } | |
1177 | ||
1178 | struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages) | |
1179 | { | |
1180 | unsigned long start, end, nr_pages; | |
1181 | struct vm_area_struct **vmas = NULL; | |
1182 | struct page **pages = NULL; | |
1183 | int i, pret, ret = -ENOMEM; | |
1184 | ||
1185 | end = (ubuf + len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
1186 | start = ubuf >> PAGE_SHIFT; | |
1187 | nr_pages = end - start; | |
1188 | ||
1189 | pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL); | |
1190 | if (!pages) | |
1191 | goto done; | |
1192 | ||
1193 | vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *), | |
1194 | GFP_KERNEL); | |
1195 | if (!vmas) | |
1196 | goto done; | |
1197 | ||
1198 | ret = 0; | |
1199 | mmap_read_lock(current->mm); | |
1200 | pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM, | |
1201 | pages, vmas); | |
1202 | if (pret == nr_pages) { | |
1203 | /* don't support file backed memory */ | |
1204 | for (i = 0; i < nr_pages; i++) { | |
1205 | struct vm_area_struct *vma = vmas[i]; | |
1206 | ||
1207 | if (vma_is_shmem(vma)) | |
1208 | continue; | |
1209 | if (vma->vm_file && | |
1210 | !is_file_hugepages(vma->vm_file)) { | |
1211 | ret = -EOPNOTSUPP; | |
1212 | break; | |
1213 | } | |
1214 | } | |
1215 | *npages = nr_pages; | |
1216 | } else { | |
1217 | ret = pret < 0 ? pret : -EFAULT; | |
1218 | } | |
1219 | mmap_read_unlock(current->mm); | |
1220 | if (ret) { | |
1221 | /* | |
1222 | * if we did partial map, or found file backed vmas, | |
1223 | * release any pages we did get | |
1224 | */ | |
1225 | if (pret > 0) | |
1226 | unpin_user_pages(pages, pret); | |
1227 | goto done; | |
1228 | } | |
1229 | ret = 0; | |
1230 | done: | |
1231 | kvfree(vmas); | |
1232 | if (ret < 0) { | |
1233 | kvfree(pages); | |
1234 | pages = ERR_PTR(ret); | |
1235 | } | |
1236 | return pages; | |
1237 | } | |
1238 | ||
1239 | static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, | |
1240 | struct io_mapped_ubuf **pimu, | |
1241 | struct page **last_hpage) | |
1242 | { | |
1243 | struct io_mapped_ubuf *imu = NULL; | |
1244 | struct page **pages = NULL; | |
1245 | unsigned long off; | |
1246 | size_t size; | |
1247 | int ret, nr_pages, i; | |
1248 | ||
5ff4fdff PB |
1249 | *pimu = ctx->dummy_ubuf; |
1250 | if (!iov->iov_base) | |
73572984 | 1251 | return 0; |
73572984 | 1252 | |
73572984 | 1253 | ret = -ENOMEM; |
73572984 JA |
1254 | pages = io_pin_pages((unsigned long) iov->iov_base, iov->iov_len, |
1255 | &nr_pages); | |
1256 | if (IS_ERR(pages)) { | |
1257 | ret = PTR_ERR(pages); | |
1258 | pages = NULL; | |
1259 | goto done; | |
1260 | } | |
1261 | ||
1262 | imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL); | |
1263 | if (!imu) | |
1264 | goto done; | |
1265 | ||
1266 | ret = io_buffer_account_pin(ctx, pages, nr_pages, imu, last_hpage); | |
1267 | if (ret) { | |
1268 | unpin_user_pages(pages, nr_pages); | |
1269 | goto done; | |
1270 | } | |
1271 | ||
1272 | off = (unsigned long) iov->iov_base & ~PAGE_MASK; | |
1273 | size = iov->iov_len; | |
1274 | for (i = 0; i < nr_pages; i++) { | |
1275 | size_t vec_len; | |
1276 | ||
1277 | vec_len = min_t(size_t, size, PAGE_SIZE - off); | |
1278 | imu->bvec[i].bv_page = pages[i]; | |
1279 | imu->bvec[i].bv_len = vec_len; | |
1280 | imu->bvec[i].bv_offset = off; | |
1281 | off = 0; | |
1282 | size -= vec_len; | |
1283 | } | |
1284 | /* store original address for later verification */ | |
1285 | imu->ubuf = (unsigned long) iov->iov_base; | |
1286 | imu->ubuf_end = imu->ubuf + iov->iov_len; | |
1287 | imu->nr_bvecs = nr_pages; | |
1288 | *pimu = imu; | |
1289 | ret = 0; | |
1290 | done: | |
1291 | if (ret) | |
1292 | kvfree(imu); | |
1293 | kvfree(pages); | |
1294 | return ret; | |
1295 | } | |
1296 | ||
1297 | static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args) | |
1298 | { | |
1299 | ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL); | |
1300 | return ctx->user_bufs ? 0 : -ENOMEM; | |
1301 | } | |
1302 | ||
1303 | int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg, | |
1304 | unsigned int nr_args, u64 __user *tags) | |
1305 | { | |
1306 | struct page *last_hpage = NULL; | |
1307 | struct io_rsrc_data *data; | |
1308 | int i, ret; | |
1309 | struct iovec iov; | |
1310 | ||
1311 | BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16)); | |
1312 | ||
1313 | if (ctx->user_bufs) | |
1314 | return -EBUSY; | |
1315 | if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS) | |
1316 | return -EINVAL; | |
1317 | ret = io_rsrc_node_switch_start(ctx); | |
1318 | if (ret) | |
1319 | return ret; | |
1320 | ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data); | |
1321 | if (ret) | |
1322 | return ret; | |
1323 | ret = io_buffers_map_alloc(ctx, nr_args); | |
1324 | if (ret) { | |
1325 | io_rsrc_data_free(data); | |
1326 | return ret; | |
1327 | } | |
1328 | ||
1329 | for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) { | |
1330 | if (arg) { | |
1331 | ret = io_copy_iov(ctx, &iov, arg, i); | |
1332 | if (ret) | |
1333 | break; | |
1334 | ret = io_buffer_validate(&iov); | |
1335 | if (ret) | |
1336 | break; | |
1337 | } else { | |
1338 | memset(&iov, 0, sizeof(iov)); | |
1339 | } | |
1340 | ||
1341 | if (!iov.iov_base && *io_get_tag_slot(data, i)) { | |
1342 | ret = -EINVAL; | |
1343 | break; | |
1344 | } | |
1345 | ||
1346 | ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i], | |
1347 | &last_hpage); | |
1348 | if (ret) | |
1349 | break; | |
1350 | } | |
1351 | ||
1352 | WARN_ON_ONCE(ctx->buf_data); | |
1353 | ||
1354 | ctx->buf_data = data; | |
1355 | if (ret) | |
1356 | __io_sqe_buffers_unregister(ctx); | |
1357 | else | |
1358 | io_rsrc_node_switch(ctx, NULL); | |
1359 | return ret; | |
1360 | } | |
c059f785 PB |
1361 | |
1362 | int io_import_fixed(int ddir, struct iov_iter *iter, | |
1363 | struct io_mapped_ubuf *imu, | |
1364 | u64 buf_addr, size_t len) | |
1365 | { | |
1366 | u64 buf_end; | |
1367 | size_t offset; | |
1368 | ||
1369 | if (WARN_ON_ONCE(!imu)) | |
1370 | return -EFAULT; | |
1371 | if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end))) | |
1372 | return -EFAULT; | |
1373 | /* not inside the mapped region */ | |
1374 | if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end)) | |
1375 | return -EFAULT; | |
1376 | ||
1377 | /* | |
1378 | * May not be a start of buffer, set size appropriately | |
1379 | * and advance us to the beginning. | |
1380 | */ | |
1381 | offset = buf_addr - imu->ubuf; | |
1382 | iov_iter_bvec(iter, ddir, imu->bvec, imu->nr_bvecs, offset + len); | |
1383 | ||
1384 | if (offset) { | |
1385 | /* | |
1386 | * Don't use iov_iter_advance() here, as it's really slow for | |
1387 | * using the latter parts of a big fixed buffer - it iterates | |
1388 | * over each segment manually. We can cheat a bit here, because | |
1389 | * we know that: | |
1390 | * | |
1391 | * 1) it's a BVEC iter, we set it up | |
1392 | * 2) all bvecs are PAGE_SIZE in size, except potentially the | |
1393 | * first and last bvec | |
1394 | * | |
1395 | * So just find our index, and adjust the iterator afterwards. | |
1396 | * If the offset is within the first bvec (or the whole first | |
1397 | * bvec, just use iov_iter_advance(). This makes it easier | |
1398 | * since we can just skip the first segment, which may not | |
1399 | * be PAGE_SIZE aligned. | |
1400 | */ | |
1401 | const struct bio_vec *bvec = imu->bvec; | |
1402 | ||
1403 | if (offset <= bvec->bv_len) { | |
1404 | iov_iter_advance(iter, offset); | |
1405 | } else { | |
1406 | unsigned long seg_skip; | |
1407 | ||
1408 | /* skip first vec */ | |
1409 | offset -= bvec->bv_len; | |
1410 | seg_skip = 1 + (offset >> PAGE_SHIFT); | |
1411 | ||
1412 | iter->bvec = bvec + seg_skip; | |
1413 | iter->nr_segs -= seg_skip; | |
1414 | iter->count -= bvec->bv_len + offset; | |
1415 | iter->iov_offset = offset & ~PAGE_MASK; | |
1416 | } | |
1417 | } | |
1418 | ||
1419 | return 0; | |
1420 | } |