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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" | |
18 | ||
19 | struct io_rsrc_update { | |
20 | struct file *file; | |
21 | u64 arg; | |
22 | u32 nr_args; | |
23 | u32 offset; | |
24 | }; | |
25 | ||
26 | static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, | |
27 | struct io_mapped_ubuf **pimu, | |
28 | struct page **last_hpage); | |
29 | ||
73572984 JA |
30 | /* only define max */ |
31 | #define IORING_MAX_FIXED_FILES (1U << 20) | |
32 | #define IORING_MAX_REG_BUFFERS (1U << 14) | |
33 | ||
6a9ce66f | 34 | int __io_account_mem(struct user_struct *user, unsigned long nr_pages) |
73572984 JA |
35 | { |
36 | unsigned long page_limit, cur_pages, new_pages; | |
37 | ||
6a9ce66f PB |
38 | if (!nr_pages) |
39 | return 0; | |
40 | ||
73572984 JA |
41 | /* Don't allow more pages than we can safely lock */ |
42 | page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; | |
43 | ||
4ccc6db0 | 44 | cur_pages = atomic_long_read(&user->locked_vm); |
73572984 | 45 | do { |
73572984 JA |
46 | new_pages = cur_pages + nr_pages; |
47 | if (new_pages > page_limit) | |
48 | return -ENOMEM; | |
4ccc6db0 UB |
49 | } while (!atomic_long_try_cmpxchg(&user->locked_vm, |
50 | &cur_pages, new_pages)); | |
73572984 JA |
51 | return 0; |
52 | } | |
53 | ||
54 | static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) | |
55 | { | |
56 | if (ctx->user) | |
57 | __io_unaccount_mem(ctx->user, nr_pages); | |
58 | ||
59 | if (ctx->mm_account) | |
60 | atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm); | |
61 | } | |
62 | ||
63 | static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) | |
64 | { | |
65 | int ret; | |
66 | ||
67 | if (ctx->user) { | |
68 | ret = __io_account_mem(ctx->user, nr_pages); | |
69 | if (ret) | |
70 | return ret; | |
71 | } | |
72 | ||
73 | if (ctx->mm_account) | |
74 | atomic64_add(nr_pages, &ctx->mm_account->pinned_vm); | |
75 | ||
76 | return 0; | |
77 | } | |
78 | ||
79 | static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst, | |
80 | void __user *arg, unsigned index) | |
81 | { | |
82 | struct iovec __user *src; | |
83 | ||
84 | #ifdef CONFIG_COMPAT | |
85 | if (ctx->compat) { | |
86 | struct compat_iovec __user *ciovs; | |
87 | struct compat_iovec ciov; | |
88 | ||
89 | ciovs = (struct compat_iovec __user *) arg; | |
90 | if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov))) | |
91 | return -EFAULT; | |
92 | ||
93 | dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base); | |
94 | dst->iov_len = ciov.iov_len; | |
95 | return 0; | |
96 | } | |
97 | #endif | |
98 | src = (struct iovec __user *) arg; | |
99 | if (copy_from_user(dst, &src[index], sizeof(*dst))) | |
100 | return -EFAULT; | |
101 | return 0; | |
102 | } | |
103 | ||
104 | static int io_buffer_validate(struct iovec *iov) | |
105 | { | |
106 | unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1); | |
107 | ||
108 | /* | |
109 | * Don't impose further limits on the size and buffer | |
110 | * constraints here, we'll -EINVAL later when IO is | |
111 | * submitted if they are wrong. | |
112 | */ | |
113 | if (!iov->iov_base) | |
114 | return iov->iov_len ? -EFAULT : 0; | |
115 | if (!iov->iov_len) | |
116 | return -EFAULT; | |
117 | ||
118 | /* arbitrary limit, but we need something */ | |
119 | if (iov->iov_len > SZ_1G) | |
120 | return -EFAULT; | |
121 | ||
122 | if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp)) | |
123 | return -EOVERFLOW; | |
124 | ||
125 | return 0; | |
126 | } | |
127 | ||
128 | static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot) | |
129 | { | |
130 | struct io_mapped_ubuf *imu = *slot; | |
131 | unsigned int i; | |
132 | ||
133 | if (imu != ctx->dummy_ubuf) { | |
134 | for (i = 0; i < imu->nr_bvecs; i++) | |
135 | unpin_user_page(imu->bvec[i].bv_page); | |
136 | if (imu->acct_pages) | |
137 | io_unaccount_mem(ctx, imu->acct_pages); | |
138 | kvfree(imu); | |
139 | } | |
140 | *slot = NULL; | |
141 | } | |
142 | ||
ff7c75ec PB |
143 | static void io_rsrc_put_work_one(struct io_rsrc_data *rsrc_data, |
144 | struct io_rsrc_put *prsrc) | |
145 | { | |
146 | struct io_ring_ctx *ctx = rsrc_data->ctx; | |
147 | ||
36b9818a PB |
148 | if (prsrc->tag) |
149 | io_post_aux_cqe(ctx, prsrc->tag, 0, 0); | |
ff7c75ec PB |
150 | rsrc_data->do_put(ctx, prsrc); |
151 | } | |
152 | ||
73572984 JA |
153 | static void __io_rsrc_put_work(struct io_rsrc_node *ref_node) |
154 | { | |
155 | struct io_rsrc_data *rsrc_data = ref_node->rsrc_data; | |
73572984 JA |
156 | struct io_rsrc_put *prsrc, *tmp; |
157 | ||
ff7c75ec PB |
158 | if (ref_node->inline_items) |
159 | io_rsrc_put_work_one(rsrc_data, &ref_node->item); | |
160 | ||
c824986c | 161 | list_for_each_entry_safe(prsrc, tmp, &ref_node->item_list, list) { |
73572984 | 162 | list_del(&prsrc->list); |
ff7c75ec | 163 | io_rsrc_put_work_one(rsrc_data, prsrc); |
73572984 JA |
164 | kfree(prsrc); |
165 | } | |
166 | ||
9eae8655 | 167 | io_rsrc_node_destroy(rsrc_data->ctx, ref_node); |
73572984 JA |
168 | } |
169 | ||
9eae8655 | 170 | void io_rsrc_node_destroy(struct io_ring_ctx *ctx, struct io_rsrc_node *node) |
73572984 | 171 | { |
9eae8655 PB |
172 | if (!io_alloc_cache_put(&ctx->rsrc_node_cache, &node->cache)) |
173 | kfree(node); | |
73572984 JA |
174 | } |
175 | ||
ef8ae64f PB |
176 | void io_rsrc_node_ref_zero(struct io_rsrc_node *node) |
177 | __must_hold(&node->rsrc_data->ctx->uring_lock) | |
73572984 | 178 | { |
73572984 | 179 | struct io_ring_ctx *ctx = node->rsrc_data->ctx; |
73572984 | 180 | |
73572984 JA |
181 | while (!list_empty(&ctx->rsrc_ref_list)) { |
182 | node = list_first_entry(&ctx->rsrc_ref_list, | |
183 | struct io_rsrc_node, node); | |
184 | /* recycle ref nodes in order */ | |
c732ea24 | 185 | if (node->refs) |
73572984 | 186 | break; |
36b9818a PB |
187 | list_del(&node->node); |
188 | __io_rsrc_put_work(node); | |
d34b1b0b | 189 | } |
0b222eeb PB |
190 | if (list_empty(&ctx->rsrc_ref_list) && unlikely(ctx->rsrc_quiesce)) |
191 | wake_up_all(&ctx->rsrc_quiesce_wq); | |
73572984 JA |
192 | } |
193 | ||
2933ae6e | 194 | struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx) |
73572984 JA |
195 | { |
196 | struct io_rsrc_node *ref_node; | |
9eae8655 PB |
197 | struct io_cache_entry *entry; |
198 | ||
199 | entry = io_alloc_cache_get(&ctx->rsrc_node_cache); | |
200 | if (entry) { | |
201 | ref_node = container_of(entry, struct io_rsrc_node, cache); | |
202 | } else { | |
203 | ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL); | |
204 | if (!ref_node) | |
205 | return NULL; | |
206 | } | |
73572984 | 207 | |
13c22396 | 208 | ref_node->rsrc_data = NULL; |
ef8ae64f | 209 | ref_node->refs = 1; |
73572984 | 210 | INIT_LIST_HEAD(&ref_node->node); |
c824986c | 211 | INIT_LIST_HEAD(&ref_node->item_list); |
ff7c75ec | 212 | ref_node->inline_items = 0; |
73572984 JA |
213 | return ref_node; |
214 | } | |
215 | ||
216 | void io_rsrc_node_switch(struct io_ring_ctx *ctx, | |
217 | struct io_rsrc_data *data_to_kill) | |
218 | __must_hold(&ctx->uring_lock) | |
219 | { | |
2933ae6e PB |
220 | struct io_rsrc_node *node = ctx->rsrc_node; |
221 | struct io_rsrc_node *backup = io_rsrc_node_alloc(ctx); | |
73572984 | 222 | |
2933ae6e PB |
223 | if (WARN_ON_ONCE(!backup)) |
224 | return; | |
73572984 | 225 | |
2933ae6e PB |
226 | node->rsrc_data = data_to_kill; |
227 | list_add_tail(&node->node, &ctx->rsrc_ref_list); | |
228 | /* put master ref */ | |
229 | io_put_rsrc_node(ctx, node); | |
230 | ctx->rsrc_node = backup; | |
73572984 JA |
231 | } |
232 | ||
2f2af35f | 233 | int __io_rsrc_node_switch_start(struct io_ring_ctx *ctx) |
73572984 | 234 | { |
2f2af35f | 235 | struct io_rsrc_node *node = kzalloc(sizeof(*node), GFP_KERNEL); |
528407b1 | 236 | |
2f2af35f PB |
237 | if (!node) |
238 | return -ENOMEM; | |
239 | io_alloc_cache_put(&ctx->rsrc_node_cache, &node->cache); | |
528407b1 | 240 | return 0; |
73572984 JA |
241 | } |
242 | ||
243 | __cold static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, | |
244 | struct io_ring_ctx *ctx) | |
245 | { | |
4ea15b56 | 246 | DEFINE_WAIT(we); |
73572984 JA |
247 | int ret; |
248 | ||
249 | /* As we may drop ->uring_lock, other task may have started quiesce */ | |
250 | if (data->quiesce) | |
251 | return -ENXIO; | |
77e3202a PB |
252 | ret = io_rsrc_node_switch_start(ctx); |
253 | if (ret) | |
254 | return ret; | |
255 | io_rsrc_node_switch(ctx, data); | |
256 | ||
0b222eeb | 257 | if (list_empty(&ctx->rsrc_ref_list)) |
77e3202a | 258 | return 0; |
73572984 | 259 | |
7d481e03 PB |
260 | if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) { |
261 | atomic_set(&ctx->cq_wait_nr, 1); | |
262 | smp_mb(); | |
263 | } | |
264 | ||
0b222eeb | 265 | ctx->rsrc_quiesce++; |
73572984 JA |
266 | data->quiesce = true; |
267 | do { | |
4ea15b56 | 268 | prepare_to_wait(&ctx->rsrc_quiesce_wq, &we, TASK_INTERRUPTIBLE); |
eef81fca | 269 | mutex_unlock(&ctx->uring_lock); |
4ea15b56 | 270 | |
ef67fcb4 | 271 | ret = io_run_task_work_sig(ctx); |
77e3202a | 272 | if (ret < 0) { |
77e3202a | 273 | mutex_lock(&ctx->uring_lock); |
0b222eeb | 274 | if (list_empty(&ctx->rsrc_ref_list)) |
757ef468 | 275 | ret = 0; |
77e3202a PB |
276 | break; |
277 | } | |
4ea15b56 PB |
278 | |
279 | schedule(); | |
280 | __set_current_state(TASK_RUNNING); | |
eef81fca PB |
281 | mutex_lock(&ctx->uring_lock); |
282 | ret = 0; | |
0b222eeb | 283 | } while (!list_empty(&ctx->rsrc_ref_list)); |
73572984 | 284 | |
4ea15b56 PB |
285 | finish_wait(&ctx->rsrc_quiesce_wq, &we); |
286 | data->quiesce = false; | |
0b222eeb PB |
287 | ctx->rsrc_quiesce--; |
288 | ||
7d481e03 PB |
289 | if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) { |
290 | atomic_set(&ctx->cq_wait_nr, 0); | |
291 | smp_mb(); | |
292 | } | |
73572984 JA |
293 | return ret; |
294 | } | |
295 | ||
296 | static void io_free_page_table(void **table, size_t size) | |
297 | { | |
298 | unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); | |
299 | ||
300 | for (i = 0; i < nr_tables; i++) | |
301 | kfree(table[i]); | |
302 | kfree(table); | |
303 | } | |
304 | ||
305 | static void io_rsrc_data_free(struct io_rsrc_data *data) | |
306 | { | |
307 | size_t size = data->nr * sizeof(data->tags[0][0]); | |
308 | ||
309 | if (data->tags) | |
310 | io_free_page_table((void **)data->tags, size); | |
311 | kfree(data); | |
312 | } | |
313 | ||
314 | static __cold void **io_alloc_page_table(size_t size) | |
315 | { | |
316 | unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); | |
317 | size_t init_size = size; | |
318 | void **table; | |
319 | ||
320 | table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT); | |
321 | if (!table) | |
322 | return NULL; | |
323 | ||
324 | for (i = 0; i < nr_tables; i++) { | |
325 | unsigned int this_size = min_t(size_t, size, PAGE_SIZE); | |
326 | ||
327 | table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT); | |
328 | if (!table[i]) { | |
329 | io_free_page_table(table, init_size); | |
330 | return NULL; | |
331 | } | |
332 | size -= this_size; | |
333 | } | |
334 | return table; | |
335 | } | |
336 | ||
337 | __cold static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, | |
338 | rsrc_put_fn *do_put, u64 __user *utags, | |
339 | unsigned nr, struct io_rsrc_data **pdata) | |
340 | { | |
341 | struct io_rsrc_data *data; | |
6acd352d | 342 | int ret = 0; |
73572984 JA |
343 | unsigned i; |
344 | ||
345 | data = kzalloc(sizeof(*data), GFP_KERNEL); | |
346 | if (!data) | |
347 | return -ENOMEM; | |
348 | data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0])); | |
349 | if (!data->tags) { | |
350 | kfree(data); | |
351 | return -ENOMEM; | |
352 | } | |
353 | ||
354 | data->nr = nr; | |
355 | data->ctx = ctx; | |
356 | data->do_put = do_put; | |
357 | if (utags) { | |
358 | ret = -EFAULT; | |
359 | for (i = 0; i < nr; i++) { | |
360 | u64 *tag_slot = io_get_tag_slot(data, i); | |
361 | ||
362 | if (copy_from_user(tag_slot, &utags[i], | |
363 | sizeof(*tag_slot))) | |
364 | goto fail; | |
365 | } | |
366 | } | |
73572984 JA |
367 | *pdata = data; |
368 | return 0; | |
369 | fail: | |
370 | io_rsrc_data_free(data); | |
371 | return ret; | |
372 | } | |
373 | ||
374 | static int __io_sqe_files_update(struct io_ring_ctx *ctx, | |
375 | struct io_uring_rsrc_update2 *up, | |
376 | unsigned nr_args) | |
377 | { | |
378 | u64 __user *tags = u64_to_user_ptr(up->tags); | |
379 | __s32 __user *fds = u64_to_user_ptr(up->data); | |
380 | struct io_rsrc_data *data = ctx->file_data; | |
381 | struct io_fixed_file *file_slot; | |
382 | struct file *file; | |
383 | int fd, i, err = 0; | |
384 | unsigned int done; | |
385 | bool needs_switch = false; | |
386 | ||
387 | if (!ctx->file_data) | |
388 | return -ENXIO; | |
389 | if (up->offset + nr_args > ctx->nr_user_files) | |
390 | return -EINVAL; | |
391 | ||
392 | for (done = 0; done < nr_args; done++) { | |
393 | u64 tag = 0; | |
394 | ||
395 | if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) || | |
396 | copy_from_user(&fd, &fds[done], sizeof(fd))) { | |
397 | err = -EFAULT; | |
398 | break; | |
399 | } | |
400 | if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) { | |
401 | err = -EINVAL; | |
402 | break; | |
403 | } | |
404 | if (fd == IORING_REGISTER_FILES_SKIP) | |
405 | continue; | |
406 | ||
407 | i = array_index_nospec(up->offset + done, ctx->nr_user_files); | |
408 | file_slot = io_fixed_file_slot(&ctx->file_table, i); | |
409 | ||
410 | if (file_slot->file_ptr) { | |
411 | file = (struct file *)(file_slot->file_ptr & FFS_MASK); | |
412 | err = io_queue_rsrc_removal(data, i, ctx->rsrc_node, file); | |
413 | if (err) | |
414 | break; | |
415 | file_slot->file_ptr = 0; | |
416 | io_file_bitmap_clear(&ctx->file_table, i); | |
417 | needs_switch = true; | |
418 | } | |
419 | if (fd != -1) { | |
420 | file = fget(fd); | |
421 | if (!file) { | |
422 | err = -EBADF; | |
423 | break; | |
424 | } | |
425 | /* | |
426 | * Don't allow io_uring instances to be registered. If | |
427 | * UNIX isn't enabled, then this causes a reference | |
428 | * cycle and this instance can never get freed. If UNIX | |
429 | * is enabled we'll handle it just fine, but there's | |
430 | * still no point in allowing a ring fd as it doesn't | |
431 | * support regular read/write anyway. | |
432 | */ | |
433 | if (io_is_uring_fops(file)) { | |
434 | fput(file); | |
435 | err = -EBADF; | |
436 | break; | |
437 | } | |
438 | err = io_scm_file_account(ctx, file); | |
439 | if (err) { | |
440 | fput(file); | |
441 | break; | |
442 | } | |
443 | *io_get_tag_slot(data, i) = tag; | |
444 | io_fixed_file_set(file_slot, file); | |
445 | io_file_bitmap_set(&ctx->file_table, i); | |
446 | } | |
447 | } | |
448 | ||
449 | if (needs_switch) | |
450 | io_rsrc_node_switch(ctx, data); | |
451 | return done ? done : err; | |
452 | } | |
453 | ||
454 | static int __io_sqe_buffers_update(struct io_ring_ctx *ctx, | |
455 | struct io_uring_rsrc_update2 *up, | |
456 | unsigned int nr_args) | |
457 | { | |
458 | u64 __user *tags = u64_to_user_ptr(up->tags); | |
459 | struct iovec iov, __user *iovs = u64_to_user_ptr(up->data); | |
460 | struct page *last_hpage = NULL; | |
461 | bool needs_switch = false; | |
462 | __u32 done; | |
463 | int i, err; | |
464 | ||
465 | if (!ctx->buf_data) | |
466 | return -ENXIO; | |
467 | if (up->offset + nr_args > ctx->nr_user_bufs) | |
468 | return -EINVAL; | |
469 | ||
470 | for (done = 0; done < nr_args; done++) { | |
471 | struct io_mapped_ubuf *imu; | |
73572984 JA |
472 | u64 tag = 0; |
473 | ||
474 | err = io_copy_iov(ctx, &iov, iovs, done); | |
475 | if (err) | |
476 | break; | |
477 | if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) { | |
478 | err = -EFAULT; | |
479 | break; | |
480 | } | |
481 | err = io_buffer_validate(&iov); | |
482 | if (err) | |
483 | break; | |
484 | if (!iov.iov_base && tag) { | |
485 | err = -EINVAL; | |
486 | break; | |
487 | } | |
488 | err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage); | |
489 | if (err) | |
490 | break; | |
491 | ||
9a57fffe | 492 | i = array_index_nospec(up->offset + done, ctx->nr_user_bufs); |
73572984 JA |
493 | if (ctx->user_bufs[i] != ctx->dummy_ubuf) { |
494 | err = io_queue_rsrc_removal(ctx->buf_data, i, | |
495 | ctx->rsrc_node, ctx->user_bufs[i]); | |
496 | if (unlikely(err)) { | |
497 | io_buffer_unmap(ctx, &imu); | |
498 | break; | |
499 | } | |
5ff4fdff | 500 | ctx->user_bufs[i] = ctx->dummy_ubuf; |
73572984 JA |
501 | needs_switch = true; |
502 | } | |
503 | ||
504 | ctx->user_bufs[i] = imu; | |
953c37e0 | 505 | *io_get_tag_slot(ctx->buf_data, i) = tag; |
73572984 JA |
506 | } |
507 | ||
508 | if (needs_switch) | |
509 | io_rsrc_node_switch(ctx, ctx->buf_data); | |
510 | return done ? done : err; | |
511 | } | |
512 | ||
513 | static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type, | |
514 | struct io_uring_rsrc_update2 *up, | |
515 | unsigned nr_args) | |
516 | { | |
517 | __u32 tmp; | |
518 | int err; | |
519 | ||
786788a8 PB |
520 | lockdep_assert_held(&ctx->uring_lock); |
521 | ||
73572984 JA |
522 | if (check_add_overflow(up->offset, nr_args, &tmp)) |
523 | return -EOVERFLOW; | |
524 | err = io_rsrc_node_switch_start(ctx); | |
525 | if (err) | |
526 | return err; | |
527 | ||
528 | switch (type) { | |
529 | case IORING_RSRC_FILE: | |
530 | return __io_sqe_files_update(ctx, up, nr_args); | |
531 | case IORING_RSRC_BUFFER: | |
532 | return __io_sqe_buffers_update(ctx, up, nr_args); | |
533 | } | |
534 | return -EINVAL; | |
535 | } | |
536 | ||
537 | int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg, | |
538 | unsigned nr_args) | |
539 | { | |
540 | struct io_uring_rsrc_update2 up; | |
541 | ||
542 | if (!nr_args) | |
543 | return -EINVAL; | |
544 | memset(&up, 0, sizeof(up)); | |
545 | if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update))) | |
546 | return -EFAULT; | |
547 | if (up.resv || up.resv2) | |
548 | return -EINVAL; | |
549 | return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args); | |
550 | } | |
551 | ||
552 | int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg, | |
553 | unsigned size, unsigned type) | |
554 | { | |
555 | struct io_uring_rsrc_update2 up; | |
556 | ||
557 | if (size != sizeof(up)) | |
558 | return -EINVAL; | |
559 | if (copy_from_user(&up, arg, sizeof(up))) | |
560 | return -EFAULT; | |
561 | if (!up.nr || up.resv || up.resv2) | |
562 | return -EINVAL; | |
563 | return __io_register_rsrc_update(ctx, type, &up, up.nr); | |
564 | } | |
565 | ||
566 | __cold int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg, | |
567 | unsigned int size, unsigned int type) | |
568 | { | |
569 | struct io_uring_rsrc_register rr; | |
570 | ||
571 | /* keep it extendible */ | |
572 | if (size != sizeof(rr)) | |
573 | return -EINVAL; | |
574 | ||
575 | memset(&rr, 0, sizeof(rr)); | |
576 | if (copy_from_user(&rr, arg, size)) | |
577 | return -EFAULT; | |
578 | if (!rr.nr || rr.resv2) | |
579 | return -EINVAL; | |
580 | if (rr.flags & ~IORING_RSRC_REGISTER_SPARSE) | |
581 | return -EINVAL; | |
582 | ||
583 | switch (type) { | |
584 | case IORING_RSRC_FILE: | |
585 | if (rr.flags & IORING_RSRC_REGISTER_SPARSE && rr.data) | |
586 | break; | |
587 | return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data), | |
588 | rr.nr, u64_to_user_ptr(rr.tags)); | |
589 | case IORING_RSRC_BUFFER: | |
590 | if (rr.flags & IORING_RSRC_REGISTER_SPARSE && rr.data) | |
591 | break; | |
592 | return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data), | |
593 | rr.nr, u64_to_user_ptr(rr.tags)); | |
594 | } | |
595 | return -EINVAL; | |
596 | } | |
597 | ||
d9808ceb | 598 | int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
73572984 | 599 | { |
f2ccb5ae | 600 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
73572984 JA |
601 | |
602 | if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT))) | |
603 | return -EINVAL; | |
604 | if (sqe->rw_flags || sqe->splice_fd_in) | |
605 | return -EINVAL; | |
606 | ||
607 | up->offset = READ_ONCE(sqe->off); | |
608 | up->nr_args = READ_ONCE(sqe->len); | |
609 | if (!up->nr_args) | |
610 | return -EINVAL; | |
611 | up->arg = READ_ONCE(sqe->addr); | |
612 | return 0; | |
613 | } | |
614 | ||
615 | static int io_files_update_with_index_alloc(struct io_kiocb *req, | |
616 | unsigned int issue_flags) | |
617 | { | |
f2ccb5ae | 618 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
73572984 JA |
619 | __s32 __user *fds = u64_to_user_ptr(up->arg); |
620 | unsigned int done; | |
621 | struct file *file; | |
622 | int ret, fd; | |
623 | ||
624 | if (!req->ctx->file_data) | |
625 | return -ENXIO; | |
626 | ||
627 | for (done = 0; done < up->nr_args; done++) { | |
628 | if (copy_from_user(&fd, &fds[done], sizeof(fd))) { | |
629 | ret = -EFAULT; | |
630 | break; | |
631 | } | |
632 | ||
633 | file = fget(fd); | |
634 | if (!file) { | |
635 | ret = -EBADF; | |
636 | break; | |
637 | } | |
638 | ret = io_fixed_fd_install(req, issue_flags, file, | |
639 | IORING_FILE_INDEX_ALLOC); | |
640 | if (ret < 0) | |
641 | break; | |
642 | if (copy_to_user(&fds[done], &ret, sizeof(ret))) { | |
f110ed84 | 643 | __io_close_fixed(req->ctx, issue_flags, ret); |
73572984 JA |
644 | ret = -EFAULT; |
645 | break; | |
646 | } | |
647 | } | |
648 | ||
649 | if (done) | |
650 | return done; | |
651 | return ret; | |
652 | } | |
653 | ||
d9808ceb | 654 | int io_files_update(struct io_kiocb *req, unsigned int issue_flags) |
73572984 | 655 | { |
f2ccb5ae | 656 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
73572984 JA |
657 | struct io_ring_ctx *ctx = req->ctx; |
658 | struct io_uring_rsrc_update2 up2; | |
659 | int ret; | |
660 | ||
661 | up2.offset = up->offset; | |
662 | up2.data = up->arg; | |
663 | up2.nr = 0; | |
664 | up2.tags = 0; | |
665 | up2.resv = 0; | |
666 | up2.resv2 = 0; | |
667 | ||
668 | if (up->offset == IORING_FILE_INDEX_ALLOC) { | |
669 | ret = io_files_update_with_index_alloc(req, issue_flags); | |
670 | } else { | |
671 | io_ring_submit_lock(ctx, issue_flags); | |
672 | ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE, | |
673 | &up2, up->nr_args); | |
674 | io_ring_submit_unlock(ctx, issue_flags); | |
675 | } | |
676 | ||
677 | if (ret < 0) | |
678 | req_set_fail(req); | |
679 | io_req_set_res(req, ret, 0); | |
680 | return IOU_OK; | |
681 | } | |
682 | ||
683 | int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx, | |
684 | struct io_rsrc_node *node, void *rsrc) | |
685 | { | |
686 | u64 *tag_slot = io_get_tag_slot(data, idx); | |
687 | struct io_rsrc_put *prsrc; | |
ff7c75ec | 688 | bool inline_item = true; |
73572984 | 689 | |
ff7c75ec PB |
690 | if (!node->inline_items) { |
691 | prsrc = &node->item; | |
692 | node->inline_items++; | |
693 | } else { | |
694 | prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL); | |
695 | if (!prsrc) | |
696 | return -ENOMEM; | |
697 | inline_item = false; | |
698 | } | |
73572984 JA |
699 | |
700 | prsrc->tag = *tag_slot; | |
701 | *tag_slot = 0; | |
702 | prsrc->rsrc = rsrc; | |
ff7c75ec PB |
703 | if (!inline_item) |
704 | list_add(&prsrc->list, &node->item_list); | |
73572984 JA |
705 | return 0; |
706 | } | |
707 | ||
708 | void __io_sqe_files_unregister(struct io_ring_ctx *ctx) | |
709 | { | |
73572984 JA |
710 | int i; |
711 | ||
712 | for (i = 0; i < ctx->nr_user_files; i++) { | |
713 | struct file *file = io_file_from_index(&ctx->file_table, i); | |
714 | ||
38eddb2c PB |
715 | /* skip scm accounted files, they'll be freed by ->ring_sock */ |
716 | if (!file || io_file_need_scm(file)) | |
73572984 JA |
717 | continue; |
718 | io_file_bitmap_clear(&ctx->file_table, i); | |
719 | fput(file); | |
720 | } | |
73572984 JA |
721 | |
722 | #if defined(CONFIG_UNIX) | |
723 | if (ctx->ring_sock) { | |
724 | struct sock *sock = ctx->ring_sock->sk; | |
725 | struct sk_buff *skb; | |
726 | ||
727 | while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL) | |
728 | kfree_skb(skb); | |
729 | } | |
730 | #endif | |
731 | io_free_file_tables(&ctx->file_table); | |
02a4d923 | 732 | io_file_table_set_alloc_range(ctx, 0, 0); |
73572984 JA |
733 | io_rsrc_data_free(ctx->file_data); |
734 | ctx->file_data = NULL; | |
735 | ctx->nr_user_files = 0; | |
736 | } | |
737 | ||
738 | int io_sqe_files_unregister(struct io_ring_ctx *ctx) | |
739 | { | |
740 | unsigned nr = ctx->nr_user_files; | |
741 | int ret; | |
742 | ||
743 | if (!ctx->file_data) | |
744 | return -ENXIO; | |
745 | ||
746 | /* | |
747 | * Quiesce may unlock ->uring_lock, and while it's not held | |
748 | * prevent new requests using the table. | |
749 | */ | |
750 | ctx->nr_user_files = 0; | |
751 | ret = io_rsrc_ref_quiesce(ctx->file_data, ctx); | |
752 | ctx->nr_user_files = nr; | |
753 | if (!ret) | |
754 | __io_sqe_files_unregister(ctx); | |
755 | return ret; | |
756 | } | |
757 | ||
758 | /* | |
759 | * Ensure the UNIX gc is aware of our file set, so we are certain that | |
760 | * the io_uring can be safely unregistered on process exit, even if we have | |
761 | * loops in the file referencing. We account only files that can hold other | |
762 | * files because otherwise they can't form a loop and so are not interesting | |
763 | * for GC. | |
764 | */ | |
765 | int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file) | |
766 | { | |
767 | #if defined(CONFIG_UNIX) | |
768 | struct sock *sk = ctx->ring_sock->sk; | |
769 | struct sk_buff_head *head = &sk->sk_receive_queue; | |
770 | struct scm_fp_list *fpl; | |
771 | struct sk_buff *skb; | |
772 | ||
773 | if (likely(!io_file_need_scm(file))) | |
774 | return 0; | |
775 | ||
776 | /* | |
777 | * See if we can merge this file into an existing skb SCM_RIGHTS | |
778 | * file set. If there's no room, fall back to allocating a new skb | |
779 | * and filling it in. | |
780 | */ | |
781 | spin_lock_irq(&head->lock); | |
782 | skb = skb_peek(head); | |
783 | if (skb && UNIXCB(skb).fp->count < SCM_MAX_FD) | |
784 | __skb_unlink(skb, head); | |
785 | else | |
786 | skb = NULL; | |
787 | spin_unlock_irq(&head->lock); | |
788 | ||
789 | if (!skb) { | |
790 | fpl = kzalloc(sizeof(*fpl), GFP_KERNEL); | |
791 | if (!fpl) | |
792 | return -ENOMEM; | |
793 | ||
794 | skb = alloc_skb(0, GFP_KERNEL); | |
795 | if (!skb) { | |
796 | kfree(fpl); | |
797 | return -ENOMEM; | |
798 | } | |
799 | ||
800 | fpl->user = get_uid(current_user()); | |
801 | fpl->max = SCM_MAX_FD; | |
802 | fpl->count = 0; | |
803 | ||
804 | UNIXCB(skb).fp = fpl; | |
805 | skb->sk = sk; | |
0091bfc8 | 806 | skb->scm_io_uring = 1; |
73572984 JA |
807 | skb->destructor = unix_destruct_scm; |
808 | refcount_add(skb->truesize, &sk->sk_wmem_alloc); | |
809 | } | |
810 | ||
811 | fpl = UNIXCB(skb).fp; | |
812 | fpl->fp[fpl->count++] = get_file(file); | |
813 | unix_inflight(fpl->user, file); | |
814 | skb_queue_head(head, skb); | |
815 | fput(file); | |
816 | #endif | |
817 | return 0; | |
818 | } | |
819 | ||
d581076b | 820 | static __cold void io_rsrc_file_scm_put(struct io_ring_ctx *ctx, struct file *file) |
73572984 | 821 | { |
73572984 JA |
822 | #if defined(CONFIG_UNIX) |
823 | struct sock *sock = ctx->ring_sock->sk; | |
824 | struct sk_buff_head list, *head = &sock->sk_receive_queue; | |
825 | struct sk_buff *skb; | |
826 | int i; | |
827 | ||
73572984 JA |
828 | __skb_queue_head_init(&list); |
829 | ||
830 | /* | |
831 | * Find the skb that holds this file in its SCM_RIGHTS. When found, | |
832 | * remove this entry and rearrange the file array. | |
833 | */ | |
834 | skb = skb_dequeue(head); | |
835 | while (skb) { | |
836 | struct scm_fp_list *fp; | |
837 | ||
838 | fp = UNIXCB(skb).fp; | |
839 | for (i = 0; i < fp->count; i++) { | |
840 | int left; | |
841 | ||
842 | if (fp->fp[i] != file) | |
843 | continue; | |
844 | ||
845 | unix_notinflight(fp->user, fp->fp[i]); | |
846 | left = fp->count - 1 - i; | |
847 | if (left) { | |
848 | memmove(&fp->fp[i], &fp->fp[i + 1], | |
849 | left * sizeof(struct file *)); | |
850 | } | |
851 | fp->count--; | |
852 | if (!fp->count) { | |
853 | kfree_skb(skb); | |
854 | skb = NULL; | |
855 | } else { | |
856 | __skb_queue_tail(&list, skb); | |
857 | } | |
858 | fput(file); | |
859 | file = NULL; | |
860 | break; | |
861 | } | |
862 | ||
863 | if (!file) | |
864 | break; | |
865 | ||
866 | __skb_queue_tail(&list, skb); | |
867 | ||
868 | skb = skb_dequeue(head); | |
869 | } | |
870 | ||
871 | if (skb_peek(&list)) { | |
872 | spin_lock_irq(&head->lock); | |
873 | while ((skb = __skb_dequeue(&list)) != NULL) | |
874 | __skb_queue_tail(head, skb); | |
875 | spin_unlock_irq(&head->lock); | |
876 | } | |
73572984 JA |
877 | #endif |
878 | } | |
879 | ||
d581076b PB |
880 | static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) |
881 | { | |
882 | struct file *file = prsrc->file; | |
883 | ||
884 | if (likely(!io_file_need_scm(file))) | |
885 | fput(file); | |
886 | else | |
887 | io_rsrc_file_scm_put(ctx, file); | |
888 | } | |
889 | ||
73572984 JA |
890 | int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, |
891 | unsigned nr_args, u64 __user *tags) | |
892 | { | |
893 | __s32 __user *fds = (__s32 __user *) arg; | |
894 | struct file *file; | |
895 | int fd, ret; | |
896 | unsigned i; | |
897 | ||
898 | if (ctx->file_data) | |
899 | return -EBUSY; | |
900 | if (!nr_args) | |
901 | return -EINVAL; | |
902 | if (nr_args > IORING_MAX_FIXED_FILES) | |
903 | return -EMFILE; | |
904 | if (nr_args > rlimit(RLIMIT_NOFILE)) | |
905 | return -EMFILE; | |
73572984 JA |
906 | ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args, |
907 | &ctx->file_data); | |
908 | if (ret) | |
909 | return ret; | |
910 | ||
911 | if (!io_alloc_file_tables(&ctx->file_table, nr_args)) { | |
912 | io_rsrc_data_free(ctx->file_data); | |
913 | ctx->file_data = NULL; | |
914 | return -ENOMEM; | |
915 | } | |
916 | ||
917 | for (i = 0; i < nr_args; i++, ctx->nr_user_files++) { | |
918 | struct io_fixed_file *file_slot; | |
919 | ||
920 | if (fds && copy_from_user(&fd, &fds[i], sizeof(fd))) { | |
921 | ret = -EFAULT; | |
922 | goto fail; | |
923 | } | |
924 | /* allow sparse sets */ | |
925 | if (!fds || fd == -1) { | |
926 | ret = -EINVAL; | |
927 | if (unlikely(*io_get_tag_slot(ctx->file_data, i))) | |
928 | goto fail; | |
929 | continue; | |
930 | } | |
931 | ||
932 | file = fget(fd); | |
933 | ret = -EBADF; | |
934 | if (unlikely(!file)) | |
935 | goto fail; | |
936 | ||
937 | /* | |
938 | * Don't allow io_uring instances to be registered. If UNIX | |
939 | * isn't enabled, then this causes a reference cycle and this | |
940 | * instance can never get freed. If UNIX is enabled we'll | |
941 | * handle it just fine, but there's still no point in allowing | |
942 | * a ring fd as it doesn't support regular read/write anyway. | |
943 | */ | |
944 | if (io_is_uring_fops(file)) { | |
945 | fput(file); | |
946 | goto fail; | |
947 | } | |
948 | ret = io_scm_file_account(ctx, file); | |
949 | if (ret) { | |
950 | fput(file); | |
951 | goto fail; | |
952 | } | |
953 | file_slot = io_fixed_file_slot(&ctx->file_table, i); | |
954 | io_fixed_file_set(file_slot, file); | |
955 | io_file_bitmap_set(&ctx->file_table, i); | |
956 | } | |
957 | ||
6e73dffb PB |
958 | /* default it to the whole table */ |
959 | io_file_table_set_alloc_range(ctx, 0, ctx->nr_user_files); | |
73572984 JA |
960 | return 0; |
961 | fail: | |
962 | __io_sqe_files_unregister(ctx); | |
963 | return ret; | |
964 | } | |
965 | ||
966 | static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) | |
967 | { | |
968 | io_buffer_unmap(ctx, &prsrc->buf); | |
969 | prsrc->buf = NULL; | |
970 | } | |
971 | ||
972 | void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx) | |
973 | { | |
974 | unsigned int i; | |
975 | ||
976 | for (i = 0; i < ctx->nr_user_bufs; i++) | |
977 | io_buffer_unmap(ctx, &ctx->user_bufs[i]); | |
978 | kfree(ctx->user_bufs); | |
979 | io_rsrc_data_free(ctx->buf_data); | |
980 | ctx->user_bufs = NULL; | |
981 | ctx->buf_data = NULL; | |
982 | ctx->nr_user_bufs = 0; | |
983 | } | |
984 | ||
985 | int io_sqe_buffers_unregister(struct io_ring_ctx *ctx) | |
986 | { | |
987 | unsigned nr = ctx->nr_user_bufs; | |
988 | int ret; | |
989 | ||
990 | if (!ctx->buf_data) | |
991 | return -ENXIO; | |
992 | ||
993 | /* | |
994 | * Quiesce may unlock ->uring_lock, and while it's not held | |
995 | * prevent new requests using the table. | |
996 | */ | |
997 | ctx->nr_user_bufs = 0; | |
998 | ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx); | |
999 | ctx->nr_user_bufs = nr; | |
1000 | if (!ret) | |
1001 | __io_sqe_buffers_unregister(ctx); | |
1002 | return ret; | |
1003 | } | |
1004 | ||
1005 | /* | |
1006 | * Not super efficient, but this is just a registration time. And we do cache | |
1007 | * the last compound head, so generally we'll only do a full search if we don't | |
1008 | * match that one. | |
1009 | * | |
1010 | * We check if the given compound head page has already been accounted, to | |
1011 | * avoid double accounting it. This allows us to account the full size of the | |
1012 | * page, not just the constituent pages of a huge page. | |
1013 | */ | |
1014 | static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages, | |
1015 | int nr_pages, struct page *hpage) | |
1016 | { | |
1017 | int i, j; | |
1018 | ||
1019 | /* check current page array */ | |
1020 | for (i = 0; i < nr_pages; i++) { | |
1021 | if (!PageCompound(pages[i])) | |
1022 | continue; | |
1023 | if (compound_head(pages[i]) == hpage) | |
1024 | return true; | |
1025 | } | |
1026 | ||
1027 | /* check previously registered pages */ | |
1028 | for (i = 0; i < ctx->nr_user_bufs; i++) { | |
1029 | struct io_mapped_ubuf *imu = ctx->user_bufs[i]; | |
1030 | ||
1031 | for (j = 0; j < imu->nr_bvecs; j++) { | |
1032 | if (!PageCompound(imu->bvec[j].bv_page)) | |
1033 | continue; | |
1034 | if (compound_head(imu->bvec[j].bv_page) == hpage) | |
1035 | return true; | |
1036 | } | |
1037 | } | |
1038 | ||
1039 | return false; | |
1040 | } | |
1041 | ||
1042 | static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages, | |
1043 | int nr_pages, struct io_mapped_ubuf *imu, | |
1044 | struct page **last_hpage) | |
1045 | { | |
1046 | int i, ret; | |
1047 | ||
1048 | imu->acct_pages = 0; | |
1049 | for (i = 0; i < nr_pages; i++) { | |
1050 | if (!PageCompound(pages[i])) { | |
1051 | imu->acct_pages++; | |
1052 | } else { | |
1053 | struct page *hpage; | |
1054 | ||
1055 | hpage = compound_head(pages[i]); | |
1056 | if (hpage == *last_hpage) | |
1057 | continue; | |
1058 | *last_hpage = hpage; | |
1059 | if (headpage_already_acct(ctx, pages, i, hpage)) | |
1060 | continue; | |
1061 | imu->acct_pages += page_size(hpage) >> PAGE_SHIFT; | |
1062 | } | |
1063 | } | |
1064 | ||
1065 | if (!imu->acct_pages) | |
1066 | return 0; | |
1067 | ||
1068 | ret = io_account_mem(ctx, imu->acct_pages); | |
1069 | if (ret) | |
1070 | imu->acct_pages = 0; | |
1071 | return ret; | |
1072 | } | |
1073 | ||
1074 | struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages) | |
1075 | { | |
1076 | unsigned long start, end, nr_pages; | |
1077 | struct vm_area_struct **vmas = NULL; | |
1078 | struct page **pages = NULL; | |
1079 | int i, pret, ret = -ENOMEM; | |
1080 | ||
1081 | end = (ubuf + len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
1082 | start = ubuf >> PAGE_SHIFT; | |
1083 | nr_pages = end - start; | |
1084 | ||
1085 | pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL); | |
1086 | if (!pages) | |
1087 | goto done; | |
1088 | ||
1089 | vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *), | |
1090 | GFP_KERNEL); | |
1091 | if (!vmas) | |
1092 | goto done; | |
1093 | ||
1094 | ret = 0; | |
1095 | mmap_read_lock(current->mm); | |
1096 | pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM, | |
1097 | pages, vmas); | |
1098 | if (pret == nr_pages) { | |
edd47826 PB |
1099 | struct file *file = vmas[0]->vm_file; |
1100 | ||
73572984 JA |
1101 | /* don't support file backed memory */ |
1102 | for (i = 0; i < nr_pages; i++) { | |
edd47826 PB |
1103 | if (vmas[i]->vm_file != file) { |
1104 | ret = -EINVAL; | |
1105 | break; | |
1106 | } | |
1107 | if (!file) | |
73572984 | 1108 | continue; |
edd47826 | 1109 | if (!vma_is_shmem(vmas[i]) && !is_file_hugepages(file)) { |
73572984 JA |
1110 | ret = -EOPNOTSUPP; |
1111 | break; | |
1112 | } | |
1113 | } | |
1114 | *npages = nr_pages; | |
1115 | } else { | |
1116 | ret = pret < 0 ? pret : -EFAULT; | |
1117 | } | |
1118 | mmap_read_unlock(current->mm); | |
1119 | if (ret) { | |
1120 | /* | |
1121 | * if we did partial map, or found file backed vmas, | |
1122 | * release any pages we did get | |
1123 | */ | |
1124 | if (pret > 0) | |
1125 | unpin_user_pages(pages, pret); | |
1126 | goto done; | |
1127 | } | |
1128 | ret = 0; | |
1129 | done: | |
1130 | kvfree(vmas); | |
1131 | if (ret < 0) { | |
1132 | kvfree(pages); | |
1133 | pages = ERR_PTR(ret); | |
1134 | } | |
1135 | return pages; | |
1136 | } | |
1137 | ||
1138 | static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, | |
1139 | struct io_mapped_ubuf **pimu, | |
1140 | struct page **last_hpage) | |
1141 | { | |
1142 | struct io_mapped_ubuf *imu = NULL; | |
1143 | struct page **pages = NULL; | |
1144 | unsigned long off; | |
1145 | size_t size; | |
1146 | int ret, nr_pages, i; | |
977bc873 | 1147 | struct folio *folio = NULL; |
73572984 | 1148 | |
5ff4fdff PB |
1149 | *pimu = ctx->dummy_ubuf; |
1150 | if (!iov->iov_base) | |
73572984 | 1151 | return 0; |
73572984 | 1152 | |
73572984 | 1153 | ret = -ENOMEM; |
73572984 JA |
1154 | pages = io_pin_pages((unsigned long) iov->iov_base, iov->iov_len, |
1155 | &nr_pages); | |
1156 | if (IS_ERR(pages)) { | |
1157 | ret = PTR_ERR(pages); | |
1158 | pages = NULL; | |
1159 | goto done; | |
1160 | } | |
1161 | ||
57bebf80 PB |
1162 | /* If it's a huge page, try to coalesce them into a single bvec entry */ |
1163 | if (nr_pages > 1) { | |
1164 | folio = page_folio(pages[0]); | |
1165 | for (i = 1; i < nr_pages; i++) { | |
1166 | if (page_folio(pages[i]) != folio) { | |
1167 | folio = NULL; | |
1168 | break; | |
1169 | } | |
1170 | } | |
1171 | if (folio) { | |
d2acf789 PB |
1172 | /* |
1173 | * The pages are bound to the folio, it doesn't | |
1174 | * actually unpin them but drops all but one reference, | |
1175 | * which is usually put down by io_buffer_unmap(). | |
1176 | * Note, needs a better helper. | |
1177 | */ | |
1178 | unpin_user_pages(&pages[1], nr_pages - 1); | |
57bebf80 PB |
1179 | nr_pages = 1; |
1180 | } | |
1181 | } | |
1182 | ||
73572984 JA |
1183 | imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL); |
1184 | if (!imu) | |
1185 | goto done; | |
1186 | ||
1187 | ret = io_buffer_account_pin(ctx, pages, nr_pages, imu, last_hpage); | |
1188 | if (ret) { | |
1189 | unpin_user_pages(pages, nr_pages); | |
1190 | goto done; | |
1191 | } | |
1192 | ||
1193 | off = (unsigned long) iov->iov_base & ~PAGE_MASK; | |
1194 | size = iov->iov_len; | |
57bebf80 PB |
1195 | /* store original address for later verification */ |
1196 | imu->ubuf = (unsigned long) iov->iov_base; | |
1197 | imu->ubuf_end = imu->ubuf + iov->iov_len; | |
1198 | imu->nr_bvecs = nr_pages; | |
1199 | *pimu = imu; | |
1200 | ret = 0; | |
1201 | ||
1202 | if (folio) { | |
1203 | bvec_set_page(&imu->bvec[0], pages[0], size, off); | |
1204 | goto done; | |
1205 | } | |
73572984 JA |
1206 | for (i = 0; i < nr_pages; i++) { |
1207 | size_t vec_len; | |
1208 | ||
1209 | vec_len = min_t(size_t, size, PAGE_SIZE - off); | |
cc342a21 | 1210 | bvec_set_page(&imu->bvec[i], pages[i], vec_len, off); |
73572984 JA |
1211 | off = 0; |
1212 | size -= vec_len; | |
1213 | } | |
73572984 JA |
1214 | done: |
1215 | if (ret) | |
1216 | kvfree(imu); | |
1217 | kvfree(pages); | |
1218 | return ret; | |
1219 | } | |
1220 | ||
1221 | static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args) | |
1222 | { | |
1223 | ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL); | |
1224 | return ctx->user_bufs ? 0 : -ENOMEM; | |
1225 | } | |
1226 | ||
1227 | int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg, | |
1228 | unsigned int nr_args, u64 __user *tags) | |
1229 | { | |
1230 | struct page *last_hpage = NULL; | |
1231 | struct io_rsrc_data *data; | |
1232 | int i, ret; | |
1233 | struct iovec iov; | |
1234 | ||
1235 | BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16)); | |
1236 | ||
1237 | if (ctx->user_bufs) | |
1238 | return -EBUSY; | |
1239 | if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS) | |
1240 | return -EINVAL; | |
73572984 JA |
1241 | ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data); |
1242 | if (ret) | |
1243 | return ret; | |
1244 | ret = io_buffers_map_alloc(ctx, nr_args); | |
1245 | if (ret) { | |
1246 | io_rsrc_data_free(data); | |
1247 | return ret; | |
1248 | } | |
1249 | ||
1250 | for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) { | |
1251 | if (arg) { | |
1252 | ret = io_copy_iov(ctx, &iov, arg, i); | |
1253 | if (ret) | |
1254 | break; | |
1255 | ret = io_buffer_validate(&iov); | |
1256 | if (ret) | |
1257 | break; | |
1258 | } else { | |
1259 | memset(&iov, 0, sizeof(iov)); | |
1260 | } | |
1261 | ||
1262 | if (!iov.iov_base && *io_get_tag_slot(data, i)) { | |
1263 | ret = -EINVAL; | |
1264 | break; | |
1265 | } | |
1266 | ||
1267 | ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i], | |
1268 | &last_hpage); | |
1269 | if (ret) | |
1270 | break; | |
1271 | } | |
1272 | ||
1273 | WARN_ON_ONCE(ctx->buf_data); | |
1274 | ||
1275 | ctx->buf_data = data; | |
1276 | if (ret) | |
1277 | __io_sqe_buffers_unregister(ctx); | |
73572984 JA |
1278 | return ret; |
1279 | } | |
c059f785 PB |
1280 | |
1281 | int io_import_fixed(int ddir, struct iov_iter *iter, | |
1282 | struct io_mapped_ubuf *imu, | |
1283 | u64 buf_addr, size_t len) | |
1284 | { | |
1285 | u64 buf_end; | |
1286 | size_t offset; | |
1287 | ||
1288 | if (WARN_ON_ONCE(!imu)) | |
1289 | return -EFAULT; | |
1290 | if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end))) | |
1291 | return -EFAULT; | |
1292 | /* not inside the mapped region */ | |
1293 | if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end)) | |
1294 | return -EFAULT; | |
1295 | ||
1296 | /* | |
6bf65a1b | 1297 | * Might not be a start of buffer, set size appropriately |
c059f785 PB |
1298 | * and advance us to the beginning. |
1299 | */ | |
1300 | offset = buf_addr - imu->ubuf; | |
1301 | iov_iter_bvec(iter, ddir, imu->bvec, imu->nr_bvecs, offset + len); | |
1302 | ||
1303 | if (offset) { | |
1304 | /* | |
1305 | * Don't use iov_iter_advance() here, as it's really slow for | |
1306 | * using the latter parts of a big fixed buffer - it iterates | |
1307 | * over each segment manually. We can cheat a bit here, because | |
1308 | * we know that: | |
1309 | * | |
1310 | * 1) it's a BVEC iter, we set it up | |
1311 | * 2) all bvecs are PAGE_SIZE in size, except potentially the | |
1312 | * first and last bvec | |
1313 | * | |
1314 | * So just find our index, and adjust the iterator afterwards. | |
1315 | * If the offset is within the first bvec (or the whole first | |
1316 | * bvec, just use iov_iter_advance(). This makes it easier | |
1317 | * since we can just skip the first segment, which may not | |
1318 | * be PAGE_SIZE aligned. | |
1319 | */ | |
1320 | const struct bio_vec *bvec = imu->bvec; | |
1321 | ||
1322 | if (offset <= bvec->bv_len) { | |
57bebf80 PB |
1323 | /* |
1324 | * Note, huge pages buffers consists of one large | |
1325 | * bvec entry and should always go this way. The other | |
1326 | * branch doesn't expect non PAGE_SIZE'd chunks. | |
1327 | */ | |
b000ae0e PB |
1328 | iter->bvec = bvec; |
1329 | iter->nr_segs = bvec->bv_len; | |
1330 | iter->count -= offset; | |
1331 | iter->iov_offset = offset; | |
c059f785 PB |
1332 | } else { |
1333 | unsigned long seg_skip; | |
1334 | ||
1335 | /* skip first vec */ | |
1336 | offset -= bvec->bv_len; | |
1337 | seg_skip = 1 + (offset >> PAGE_SHIFT); | |
1338 | ||
1339 | iter->bvec = bvec + seg_skip; | |
1340 | iter->nr_segs -= seg_skip; | |
1341 | iter->count -= bvec->bv_len + offset; | |
1342 | iter->iov_offset = offset & ~PAGE_MASK; | |
1343 | } | |
1344 | } | |
1345 | ||
1346 | return 0; | |
1347 | } |