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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 | ||
fc7f3a8d PB |
26 | static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc); |
27 | static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc); | |
73572984 JA |
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 | ||
73572984 JA |
32 | /* only define max */ |
33 | #define IORING_MAX_FIXED_FILES (1U << 20) | |
34 | #define IORING_MAX_REG_BUFFERS (1U << 14) | |
35 | ||
6a9ce66f | 36 | int __io_account_mem(struct user_struct *user, unsigned long nr_pages) |
73572984 JA |
37 | { |
38 | unsigned long page_limit, cur_pages, new_pages; | |
39 | ||
6a9ce66f PB |
40 | if (!nr_pages) |
41 | return 0; | |
42 | ||
73572984 JA |
43 | /* Don't allow more pages than we can safely lock */ |
44 | page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; | |
45 | ||
4ccc6db0 | 46 | cur_pages = atomic_long_read(&user->locked_vm); |
73572984 | 47 | do { |
73572984 JA |
48 | new_pages = cur_pages + nr_pages; |
49 | if (new_pages > page_limit) | |
50 | return -ENOMEM; | |
4ccc6db0 UB |
51 | } while (!atomic_long_try_cmpxchg(&user->locked_vm, |
52 | &cur_pages, new_pages)); | |
73572984 JA |
53 | return 0; |
54 | } | |
55 | ||
56 | static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) | |
57 | { | |
58 | if (ctx->user) | |
59 | __io_unaccount_mem(ctx->user, nr_pages); | |
60 | ||
61 | if (ctx->mm_account) | |
62 | atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm); | |
63 | } | |
64 | ||
65 | static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) | |
66 | { | |
67 | int ret; | |
68 | ||
69 | if (ctx->user) { | |
70 | ret = __io_account_mem(ctx->user, nr_pages); | |
71 | if (ret) | |
72 | return ret; | |
73 | } | |
74 | ||
75 | if (ctx->mm_account) | |
76 | atomic64_add(nr_pages, &ctx->mm_account->pinned_vm); | |
77 | ||
78 | return 0; | |
79 | } | |
80 | ||
81 | static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst, | |
82 | void __user *arg, unsigned index) | |
83 | { | |
84 | struct iovec __user *src; | |
85 | ||
86 | #ifdef CONFIG_COMPAT | |
87 | if (ctx->compat) { | |
88 | struct compat_iovec __user *ciovs; | |
89 | struct compat_iovec ciov; | |
90 | ||
91 | ciovs = (struct compat_iovec __user *) arg; | |
92 | if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov))) | |
93 | return -EFAULT; | |
94 | ||
95 | dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base); | |
96 | dst->iov_len = ciov.iov_len; | |
97 | return 0; | |
98 | } | |
99 | #endif | |
100 | src = (struct iovec __user *) arg; | |
101 | if (copy_from_user(dst, &src[index], sizeof(*dst))) | |
102 | return -EFAULT; | |
103 | return 0; | |
104 | } | |
105 | ||
106 | static int io_buffer_validate(struct iovec *iov) | |
107 | { | |
108 | unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1); | |
109 | ||
110 | /* | |
111 | * Don't impose further limits on the size and buffer | |
112 | * constraints here, we'll -EINVAL later when IO is | |
113 | * submitted if they are wrong. | |
114 | */ | |
115 | if (!iov->iov_base) | |
116 | return iov->iov_len ? -EFAULT : 0; | |
117 | if (!iov->iov_len) | |
118 | return -EFAULT; | |
119 | ||
120 | /* arbitrary limit, but we need something */ | |
121 | if (iov->iov_len > SZ_1G) | |
122 | return -EFAULT; | |
123 | ||
124 | if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp)) | |
125 | return -EOVERFLOW; | |
126 | ||
127 | return 0; | |
128 | } | |
129 | ||
130 | static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot) | |
131 | { | |
132 | struct io_mapped_ubuf *imu = *slot; | |
133 | unsigned int i; | |
134 | ||
135 | if (imu != ctx->dummy_ubuf) { | |
136 | for (i = 0; i < imu->nr_bvecs; i++) | |
137 | unpin_user_page(imu->bvec[i].bv_page); | |
138 | if (imu->acct_pages) | |
139 | io_unaccount_mem(ctx, imu->acct_pages); | |
140 | kvfree(imu); | |
141 | } | |
142 | *slot = NULL; | |
143 | } | |
144 | ||
29b26c55 | 145 | static void io_rsrc_put_work(struct io_rsrc_node *node) |
ff7c75ec | 146 | { |
29b26c55 | 147 | struct io_rsrc_put *prsrc = &node->item; |
ff7c75ec | 148 | |
36b9818a | 149 | if (prsrc->tag) |
2236b390 | 150 | io_post_aux_cqe(node->ctx, prsrc->tag, 0, 0); |
fc7f3a8d | 151 | |
2236b390 | 152 | switch (node->type) { |
fc7f3a8d | 153 | case IORING_RSRC_FILE: |
2236b390 | 154 | io_rsrc_file_put(node->ctx, prsrc); |
fc7f3a8d PB |
155 | break; |
156 | case IORING_RSRC_BUFFER: | |
2236b390 | 157 | io_rsrc_buf_put(node->ctx, prsrc); |
fc7f3a8d PB |
158 | break; |
159 | default: | |
160 | WARN_ON_ONCE(1); | |
161 | break; | |
162 | } | |
ff7c75ec PB |
163 | } |
164 | ||
9eae8655 | 165 | void io_rsrc_node_destroy(struct io_ring_ctx *ctx, struct io_rsrc_node *node) |
73572984 | 166 | { |
9eae8655 PB |
167 | if (!io_alloc_cache_put(&ctx->rsrc_node_cache, &node->cache)) |
168 | kfree(node); | |
73572984 JA |
169 | } |
170 | ||
ef8ae64f | 171 | void io_rsrc_node_ref_zero(struct io_rsrc_node *node) |
2236b390 | 172 | __must_hold(&node->ctx->uring_lock) |
73572984 | 173 | { |
2236b390 | 174 | struct io_ring_ctx *ctx = node->ctx; |
73572984 | 175 | |
73572984 JA |
176 | while (!list_empty(&ctx->rsrc_ref_list)) { |
177 | node = list_first_entry(&ctx->rsrc_ref_list, | |
178 | struct io_rsrc_node, node); | |
179 | /* recycle ref nodes in order */ | |
c732ea24 | 180 | if (node->refs) |
73572984 | 181 | break; |
36b9818a | 182 | list_del(&node->node); |
4130b499 PB |
183 | |
184 | if (likely(!node->empty)) | |
29b26c55 | 185 | io_rsrc_put_work(node); |
4130b499 | 186 | io_rsrc_node_destroy(ctx, node); |
d34b1b0b | 187 | } |
0b222eeb PB |
188 | if (list_empty(&ctx->rsrc_ref_list) && unlikely(ctx->rsrc_quiesce)) |
189 | wake_up_all(&ctx->rsrc_quiesce_wq); | |
73572984 JA |
190 | } |
191 | ||
2933ae6e | 192 | struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx) |
73572984 JA |
193 | { |
194 | struct io_rsrc_node *ref_node; | |
9eae8655 PB |
195 | struct io_cache_entry *entry; |
196 | ||
197 | entry = io_alloc_cache_get(&ctx->rsrc_node_cache); | |
198 | if (entry) { | |
199 | ref_node = container_of(entry, struct io_rsrc_node, cache); | |
200 | } else { | |
201 | ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL); | |
202 | if (!ref_node) | |
203 | return NULL; | |
204 | } | |
73572984 | 205 | |
2236b390 | 206 | ref_node->ctx = ctx; |
26147da3 | 207 | ref_node->empty = 0; |
c376644f | 208 | ref_node->refs = 1; |
73572984 JA |
209 | return ref_node; |
210 | } | |
211 | ||
73572984 JA |
212 | __cold static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, |
213 | struct io_ring_ctx *ctx) | |
214 | { | |
c376644f | 215 | struct io_rsrc_node *backup; |
4ea15b56 | 216 | DEFINE_WAIT(we); |
73572984 JA |
217 | int ret; |
218 | ||
c376644f | 219 | /* As We may drop ->uring_lock, other task may have started quiesce */ |
73572984 JA |
220 | if (data->quiesce) |
221 | return -ENXIO; | |
c376644f PB |
222 | |
223 | backup = io_rsrc_node_alloc(ctx); | |
224 | if (!backup) | |
225 | return -ENOMEM; | |
26147da3 | 226 | ctx->rsrc_node->empty = true; |
2236b390 | 227 | ctx->rsrc_node->type = -1; |
c376644f PB |
228 | list_add_tail(&ctx->rsrc_node->node, &ctx->rsrc_ref_list); |
229 | io_put_rsrc_node(ctx, ctx->rsrc_node); | |
230 | ctx->rsrc_node = backup; | |
77e3202a | 231 | |
0b222eeb | 232 | if (list_empty(&ctx->rsrc_ref_list)) |
77e3202a | 233 | return 0; |
73572984 | 234 | |
7d481e03 PB |
235 | if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) { |
236 | atomic_set(&ctx->cq_wait_nr, 1); | |
237 | smp_mb(); | |
238 | } | |
239 | ||
0b222eeb | 240 | ctx->rsrc_quiesce++; |
73572984 JA |
241 | data->quiesce = true; |
242 | do { | |
4ea15b56 | 243 | prepare_to_wait(&ctx->rsrc_quiesce_wq, &we, TASK_INTERRUPTIBLE); |
eef81fca | 244 | mutex_unlock(&ctx->uring_lock); |
4ea15b56 | 245 | |
ef67fcb4 | 246 | ret = io_run_task_work_sig(ctx); |
77e3202a | 247 | if (ret < 0) { |
77e3202a | 248 | mutex_lock(&ctx->uring_lock); |
0b222eeb | 249 | if (list_empty(&ctx->rsrc_ref_list)) |
757ef468 | 250 | ret = 0; |
77e3202a PB |
251 | break; |
252 | } | |
4ea15b56 PB |
253 | |
254 | schedule(); | |
255 | __set_current_state(TASK_RUNNING); | |
eef81fca PB |
256 | mutex_lock(&ctx->uring_lock); |
257 | ret = 0; | |
0b222eeb | 258 | } while (!list_empty(&ctx->rsrc_ref_list)); |
73572984 | 259 | |
4ea15b56 PB |
260 | finish_wait(&ctx->rsrc_quiesce_wq, &we); |
261 | data->quiesce = false; | |
0b222eeb PB |
262 | ctx->rsrc_quiesce--; |
263 | ||
7d481e03 PB |
264 | if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) { |
265 | atomic_set(&ctx->cq_wait_nr, 0); | |
266 | smp_mb(); | |
267 | } | |
73572984 JA |
268 | return ret; |
269 | } | |
270 | ||
271 | static void io_free_page_table(void **table, size_t size) | |
272 | { | |
273 | unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); | |
274 | ||
275 | for (i = 0; i < nr_tables; i++) | |
276 | kfree(table[i]); | |
277 | kfree(table); | |
278 | } | |
279 | ||
280 | static void io_rsrc_data_free(struct io_rsrc_data *data) | |
281 | { | |
282 | size_t size = data->nr * sizeof(data->tags[0][0]); | |
283 | ||
284 | if (data->tags) | |
285 | io_free_page_table((void **)data->tags, size); | |
286 | kfree(data); | |
287 | } | |
288 | ||
289 | static __cold void **io_alloc_page_table(size_t size) | |
290 | { | |
291 | unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); | |
292 | size_t init_size = size; | |
293 | void **table; | |
294 | ||
295 | table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT); | |
296 | if (!table) | |
297 | return NULL; | |
298 | ||
299 | for (i = 0; i < nr_tables; i++) { | |
300 | unsigned int this_size = min_t(size_t, size, PAGE_SIZE); | |
301 | ||
302 | table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT); | |
303 | if (!table[i]) { | |
304 | io_free_page_table(table, init_size); | |
305 | return NULL; | |
306 | } | |
307 | size -= this_size; | |
308 | } | |
309 | return table; | |
310 | } | |
311 | ||
fc7f3a8d PB |
312 | __cold static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, int type, |
313 | u64 __user *utags, | |
73572984 JA |
314 | unsigned nr, struct io_rsrc_data **pdata) |
315 | { | |
316 | struct io_rsrc_data *data; | |
6acd352d | 317 | int ret = 0; |
73572984 JA |
318 | unsigned i; |
319 | ||
320 | data = kzalloc(sizeof(*data), GFP_KERNEL); | |
321 | if (!data) | |
322 | return -ENOMEM; | |
323 | data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0])); | |
324 | if (!data->tags) { | |
325 | kfree(data); | |
326 | return -ENOMEM; | |
327 | } | |
328 | ||
329 | data->nr = nr; | |
330 | data->ctx = ctx; | |
fc7f3a8d | 331 | data->rsrc_type = type; |
73572984 JA |
332 | if (utags) { |
333 | ret = -EFAULT; | |
334 | for (i = 0; i < nr; i++) { | |
335 | u64 *tag_slot = io_get_tag_slot(data, i); | |
336 | ||
337 | if (copy_from_user(tag_slot, &utags[i], | |
338 | sizeof(*tag_slot))) | |
339 | goto fail; | |
340 | } | |
341 | } | |
73572984 JA |
342 | *pdata = data; |
343 | return 0; | |
344 | fail: | |
345 | io_rsrc_data_free(data); | |
346 | return ret; | |
347 | } | |
348 | ||
349 | static int __io_sqe_files_update(struct io_ring_ctx *ctx, | |
350 | struct io_uring_rsrc_update2 *up, | |
351 | unsigned nr_args) | |
352 | { | |
353 | u64 __user *tags = u64_to_user_ptr(up->tags); | |
354 | __s32 __user *fds = u64_to_user_ptr(up->data); | |
355 | struct io_rsrc_data *data = ctx->file_data; | |
356 | struct io_fixed_file *file_slot; | |
73572984 JA |
357 | int fd, i, err = 0; |
358 | unsigned int done; | |
73572984 JA |
359 | |
360 | if (!ctx->file_data) | |
361 | return -ENXIO; | |
362 | if (up->offset + nr_args > ctx->nr_user_files) | |
363 | return -EINVAL; | |
364 | ||
365 | for (done = 0; done < nr_args; done++) { | |
366 | u64 tag = 0; | |
367 | ||
368 | if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) || | |
369 | copy_from_user(&fd, &fds[done], sizeof(fd))) { | |
370 | err = -EFAULT; | |
371 | break; | |
372 | } | |
373 | if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) { | |
374 | err = -EINVAL; | |
375 | break; | |
376 | } | |
377 | if (fd == IORING_REGISTER_FILES_SKIP) | |
378 | continue; | |
379 | ||
380 | i = array_index_nospec(up->offset + done, ctx->nr_user_files); | |
381 | file_slot = io_fixed_file_slot(&ctx->file_table, i); | |
382 | ||
383 | if (file_slot->file_ptr) { | |
4bfb0c9a CH |
384 | err = io_queue_rsrc_removal(data, i, |
385 | io_slot_file(file_slot)); | |
73572984 JA |
386 | if (err) |
387 | break; | |
388 | file_slot->file_ptr = 0; | |
389 | io_file_bitmap_clear(&ctx->file_table, i); | |
73572984 JA |
390 | } |
391 | if (fd != -1) { | |
4bfb0c9a CH |
392 | struct file *file = fget(fd); |
393 | ||
73572984 JA |
394 | if (!file) { |
395 | err = -EBADF; | |
396 | break; | |
397 | } | |
398 | /* | |
399 | * Don't allow io_uring instances to be registered. If | |
400 | * UNIX isn't enabled, then this causes a reference | |
401 | * cycle and this instance can never get freed. If UNIX | |
402 | * is enabled we'll handle it just fine, but there's | |
403 | * still no point in allowing a ring fd as it doesn't | |
404 | * support regular read/write anyway. | |
405 | */ | |
406 | if (io_is_uring_fops(file)) { | |
407 | fput(file); | |
408 | err = -EBADF; | |
409 | break; | |
410 | } | |
411 | err = io_scm_file_account(ctx, file); | |
412 | if (err) { | |
413 | fput(file); | |
414 | break; | |
415 | } | |
416 | *io_get_tag_slot(data, i) = tag; | |
417 | io_fixed_file_set(file_slot, file); | |
418 | io_file_bitmap_set(&ctx->file_table, i); | |
419 | } | |
420 | } | |
73572984 JA |
421 | return done ? done : err; |
422 | } | |
423 | ||
424 | static int __io_sqe_buffers_update(struct io_ring_ctx *ctx, | |
425 | struct io_uring_rsrc_update2 *up, | |
426 | unsigned int nr_args) | |
427 | { | |
428 | u64 __user *tags = u64_to_user_ptr(up->tags); | |
429 | struct iovec iov, __user *iovs = u64_to_user_ptr(up->data); | |
430 | struct page *last_hpage = NULL; | |
73572984 JA |
431 | __u32 done; |
432 | int i, err; | |
433 | ||
434 | if (!ctx->buf_data) | |
435 | return -ENXIO; | |
436 | if (up->offset + nr_args > ctx->nr_user_bufs) | |
437 | return -EINVAL; | |
438 | ||
439 | for (done = 0; done < nr_args; done++) { | |
440 | struct io_mapped_ubuf *imu; | |
73572984 JA |
441 | u64 tag = 0; |
442 | ||
443 | err = io_copy_iov(ctx, &iov, iovs, done); | |
444 | if (err) | |
445 | break; | |
446 | if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) { | |
447 | err = -EFAULT; | |
448 | break; | |
449 | } | |
450 | err = io_buffer_validate(&iov); | |
451 | if (err) | |
452 | break; | |
453 | if (!iov.iov_base && tag) { | |
454 | err = -EINVAL; | |
455 | break; | |
456 | } | |
457 | err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage); | |
458 | if (err) | |
459 | break; | |
460 | ||
9a57fffe | 461 | i = array_index_nospec(up->offset + done, ctx->nr_user_bufs); |
73572984 JA |
462 | if (ctx->user_bufs[i] != ctx->dummy_ubuf) { |
463 | err = io_queue_rsrc_removal(ctx->buf_data, i, | |
63fea890 | 464 | ctx->user_bufs[i]); |
73572984 JA |
465 | if (unlikely(err)) { |
466 | io_buffer_unmap(ctx, &imu); | |
467 | break; | |
468 | } | |
5ff4fdff | 469 | ctx->user_bufs[i] = ctx->dummy_ubuf; |
73572984 JA |
470 | } |
471 | ||
472 | ctx->user_bufs[i] = imu; | |
953c37e0 | 473 | *io_get_tag_slot(ctx->buf_data, i) = tag; |
73572984 | 474 | } |
73572984 JA |
475 | return done ? done : err; |
476 | } | |
477 | ||
478 | static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type, | |
479 | struct io_uring_rsrc_update2 *up, | |
480 | unsigned nr_args) | |
481 | { | |
482 | __u32 tmp; | |
73572984 | 483 | |
786788a8 PB |
484 | lockdep_assert_held(&ctx->uring_lock); |
485 | ||
73572984 JA |
486 | if (check_add_overflow(up->offset, nr_args, &tmp)) |
487 | return -EOVERFLOW; | |
73572984 JA |
488 | |
489 | switch (type) { | |
490 | case IORING_RSRC_FILE: | |
491 | return __io_sqe_files_update(ctx, up, nr_args); | |
492 | case IORING_RSRC_BUFFER: | |
493 | return __io_sqe_buffers_update(ctx, up, nr_args); | |
494 | } | |
495 | return -EINVAL; | |
496 | } | |
497 | ||
498 | int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg, | |
499 | unsigned nr_args) | |
500 | { | |
501 | struct io_uring_rsrc_update2 up; | |
502 | ||
503 | if (!nr_args) | |
504 | return -EINVAL; | |
505 | memset(&up, 0, sizeof(up)); | |
506 | if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update))) | |
507 | return -EFAULT; | |
508 | if (up.resv || up.resv2) | |
509 | return -EINVAL; | |
510 | return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args); | |
511 | } | |
512 | ||
513 | int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg, | |
514 | unsigned size, unsigned type) | |
515 | { | |
516 | struct io_uring_rsrc_update2 up; | |
517 | ||
518 | if (size != sizeof(up)) | |
519 | return -EINVAL; | |
520 | if (copy_from_user(&up, arg, sizeof(up))) | |
521 | return -EFAULT; | |
522 | if (!up.nr || up.resv || up.resv2) | |
523 | return -EINVAL; | |
524 | return __io_register_rsrc_update(ctx, type, &up, up.nr); | |
525 | } | |
526 | ||
527 | __cold int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg, | |
528 | unsigned int size, unsigned int type) | |
529 | { | |
530 | struct io_uring_rsrc_register rr; | |
531 | ||
532 | /* keep it extendible */ | |
533 | if (size != sizeof(rr)) | |
534 | return -EINVAL; | |
535 | ||
536 | memset(&rr, 0, sizeof(rr)); | |
537 | if (copy_from_user(&rr, arg, size)) | |
538 | return -EFAULT; | |
539 | if (!rr.nr || rr.resv2) | |
540 | return -EINVAL; | |
541 | if (rr.flags & ~IORING_RSRC_REGISTER_SPARSE) | |
542 | return -EINVAL; | |
543 | ||
544 | switch (type) { | |
545 | case IORING_RSRC_FILE: | |
546 | if (rr.flags & IORING_RSRC_REGISTER_SPARSE && rr.data) | |
547 | break; | |
548 | return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data), | |
549 | rr.nr, u64_to_user_ptr(rr.tags)); | |
550 | case IORING_RSRC_BUFFER: | |
551 | if (rr.flags & IORING_RSRC_REGISTER_SPARSE && rr.data) | |
552 | break; | |
553 | return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data), | |
554 | rr.nr, u64_to_user_ptr(rr.tags)); | |
555 | } | |
556 | return -EINVAL; | |
557 | } | |
558 | ||
d9808ceb | 559 | int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
73572984 | 560 | { |
f2ccb5ae | 561 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
73572984 JA |
562 | |
563 | if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT))) | |
564 | return -EINVAL; | |
565 | if (sqe->rw_flags || sqe->splice_fd_in) | |
566 | return -EINVAL; | |
567 | ||
568 | up->offset = READ_ONCE(sqe->off); | |
569 | up->nr_args = READ_ONCE(sqe->len); | |
570 | if (!up->nr_args) | |
571 | return -EINVAL; | |
572 | up->arg = READ_ONCE(sqe->addr); | |
573 | return 0; | |
574 | } | |
575 | ||
576 | static int io_files_update_with_index_alloc(struct io_kiocb *req, | |
577 | unsigned int issue_flags) | |
578 | { | |
f2ccb5ae | 579 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
73572984 JA |
580 | __s32 __user *fds = u64_to_user_ptr(up->arg); |
581 | unsigned int done; | |
582 | struct file *file; | |
583 | int ret, fd; | |
584 | ||
585 | if (!req->ctx->file_data) | |
586 | return -ENXIO; | |
587 | ||
588 | for (done = 0; done < up->nr_args; done++) { | |
589 | if (copy_from_user(&fd, &fds[done], sizeof(fd))) { | |
590 | ret = -EFAULT; | |
591 | break; | |
592 | } | |
593 | ||
594 | file = fget(fd); | |
595 | if (!file) { | |
596 | ret = -EBADF; | |
597 | break; | |
598 | } | |
599 | ret = io_fixed_fd_install(req, issue_flags, file, | |
600 | IORING_FILE_INDEX_ALLOC); | |
601 | if (ret < 0) | |
602 | break; | |
603 | if (copy_to_user(&fds[done], &ret, sizeof(ret))) { | |
f110ed84 | 604 | __io_close_fixed(req->ctx, issue_flags, ret); |
73572984 JA |
605 | ret = -EFAULT; |
606 | break; | |
607 | } | |
608 | } | |
609 | ||
610 | if (done) | |
611 | return done; | |
612 | return ret; | |
613 | } | |
614 | ||
d9808ceb | 615 | int io_files_update(struct io_kiocb *req, unsigned int issue_flags) |
73572984 | 616 | { |
f2ccb5ae | 617 | struct io_rsrc_update *up = io_kiocb_to_cmd(req, struct io_rsrc_update); |
73572984 JA |
618 | struct io_ring_ctx *ctx = req->ctx; |
619 | struct io_uring_rsrc_update2 up2; | |
620 | int ret; | |
621 | ||
622 | up2.offset = up->offset; | |
623 | up2.data = up->arg; | |
624 | up2.nr = 0; | |
625 | up2.tags = 0; | |
626 | up2.resv = 0; | |
627 | up2.resv2 = 0; | |
628 | ||
629 | if (up->offset == IORING_FILE_INDEX_ALLOC) { | |
630 | ret = io_files_update_with_index_alloc(req, issue_flags); | |
631 | } else { | |
632 | io_ring_submit_lock(ctx, issue_flags); | |
633 | ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE, | |
634 | &up2, up->nr_args); | |
635 | io_ring_submit_unlock(ctx, issue_flags); | |
636 | } | |
637 | ||
638 | if (ret < 0) | |
639 | req_set_fail(req); | |
640 | io_req_set_res(req, ret, 0); | |
641 | return IOU_OK; | |
642 | } | |
643 | ||
63fea890 | 644 | int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx, void *rsrc) |
73572984 | 645 | { |
63fea890 PB |
646 | struct io_ring_ctx *ctx = data->ctx; |
647 | struct io_rsrc_node *node = ctx->rsrc_node; | |
73572984 | 648 | u64 *tag_slot = io_get_tag_slot(data, idx); |
73572984 | 649 | |
c376644f PB |
650 | ctx->rsrc_node = io_rsrc_node_alloc(ctx); |
651 | if (unlikely(!ctx->rsrc_node)) { | |
652 | ctx->rsrc_node = node; | |
653 | return -ENOMEM; | |
ff7c75ec | 654 | } |
73572984 | 655 | |
c376644f | 656 | node->item.rsrc = rsrc; |
2236b390 | 657 | node->type = data->rsrc_type; |
c376644f | 658 | node->item.tag = *tag_slot; |
73572984 | 659 | *tag_slot = 0; |
c376644f PB |
660 | list_add_tail(&node->node, &ctx->rsrc_ref_list); |
661 | io_put_rsrc_node(ctx, node); | |
73572984 JA |
662 | return 0; |
663 | } | |
664 | ||
665 | void __io_sqe_files_unregister(struct io_ring_ctx *ctx) | |
666 | { | |
73572984 JA |
667 | int i; |
668 | ||
669 | for (i = 0; i < ctx->nr_user_files; i++) { | |
670 | struct file *file = io_file_from_index(&ctx->file_table, i); | |
671 | ||
38eddb2c PB |
672 | /* skip scm accounted files, they'll be freed by ->ring_sock */ |
673 | if (!file || io_file_need_scm(file)) | |
73572984 JA |
674 | continue; |
675 | io_file_bitmap_clear(&ctx->file_table, i); | |
676 | fput(file); | |
677 | } | |
73572984 JA |
678 | |
679 | #if defined(CONFIG_UNIX) | |
680 | if (ctx->ring_sock) { | |
681 | struct sock *sock = ctx->ring_sock->sk; | |
682 | struct sk_buff *skb; | |
683 | ||
684 | while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL) | |
685 | kfree_skb(skb); | |
686 | } | |
687 | #endif | |
688 | io_free_file_tables(&ctx->file_table); | |
02a4d923 | 689 | io_file_table_set_alloc_range(ctx, 0, 0); |
73572984 JA |
690 | io_rsrc_data_free(ctx->file_data); |
691 | ctx->file_data = NULL; | |
692 | ctx->nr_user_files = 0; | |
693 | } | |
694 | ||
695 | int io_sqe_files_unregister(struct io_ring_ctx *ctx) | |
696 | { | |
697 | unsigned nr = ctx->nr_user_files; | |
698 | int ret; | |
699 | ||
700 | if (!ctx->file_data) | |
701 | return -ENXIO; | |
702 | ||
703 | /* | |
704 | * Quiesce may unlock ->uring_lock, and while it's not held | |
705 | * prevent new requests using the table. | |
706 | */ | |
707 | ctx->nr_user_files = 0; | |
708 | ret = io_rsrc_ref_quiesce(ctx->file_data, ctx); | |
709 | ctx->nr_user_files = nr; | |
710 | if (!ret) | |
711 | __io_sqe_files_unregister(ctx); | |
712 | return ret; | |
713 | } | |
714 | ||
715 | /* | |
716 | * Ensure the UNIX gc is aware of our file set, so we are certain that | |
717 | * the io_uring can be safely unregistered on process exit, even if we have | |
718 | * loops in the file referencing. We account only files that can hold other | |
719 | * files because otherwise they can't form a loop and so are not interesting | |
720 | * for GC. | |
721 | */ | |
722 | int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file) | |
723 | { | |
724 | #if defined(CONFIG_UNIX) | |
725 | struct sock *sk = ctx->ring_sock->sk; | |
726 | struct sk_buff_head *head = &sk->sk_receive_queue; | |
727 | struct scm_fp_list *fpl; | |
728 | struct sk_buff *skb; | |
729 | ||
730 | if (likely(!io_file_need_scm(file))) | |
731 | return 0; | |
732 | ||
733 | /* | |
734 | * See if we can merge this file into an existing skb SCM_RIGHTS | |
735 | * file set. If there's no room, fall back to allocating a new skb | |
736 | * and filling it in. | |
737 | */ | |
738 | spin_lock_irq(&head->lock); | |
739 | skb = skb_peek(head); | |
740 | if (skb && UNIXCB(skb).fp->count < SCM_MAX_FD) | |
741 | __skb_unlink(skb, head); | |
742 | else | |
743 | skb = NULL; | |
744 | spin_unlock_irq(&head->lock); | |
745 | ||
746 | if (!skb) { | |
747 | fpl = kzalloc(sizeof(*fpl), GFP_KERNEL); | |
748 | if (!fpl) | |
749 | return -ENOMEM; | |
750 | ||
751 | skb = alloc_skb(0, GFP_KERNEL); | |
752 | if (!skb) { | |
753 | kfree(fpl); | |
754 | return -ENOMEM; | |
755 | } | |
756 | ||
757 | fpl->user = get_uid(current_user()); | |
758 | fpl->max = SCM_MAX_FD; | |
759 | fpl->count = 0; | |
760 | ||
761 | UNIXCB(skb).fp = fpl; | |
762 | skb->sk = sk; | |
10369080 | 763 | skb->destructor = io_uring_destruct_scm; |
73572984 JA |
764 | refcount_add(skb->truesize, &sk->sk_wmem_alloc); |
765 | } | |
766 | ||
767 | fpl = UNIXCB(skb).fp; | |
768 | fpl->fp[fpl->count++] = get_file(file); | |
769 | unix_inflight(fpl->user, file); | |
770 | skb_queue_head(head, skb); | |
771 | fput(file); | |
772 | #endif | |
773 | return 0; | |
774 | } | |
775 | ||
d581076b | 776 | static __cold void io_rsrc_file_scm_put(struct io_ring_ctx *ctx, struct file *file) |
73572984 | 777 | { |
73572984 JA |
778 | #if defined(CONFIG_UNIX) |
779 | struct sock *sock = ctx->ring_sock->sk; | |
780 | struct sk_buff_head list, *head = &sock->sk_receive_queue; | |
781 | struct sk_buff *skb; | |
782 | int i; | |
783 | ||
73572984 JA |
784 | __skb_queue_head_init(&list); |
785 | ||
786 | /* | |
787 | * Find the skb that holds this file in its SCM_RIGHTS. When found, | |
788 | * remove this entry and rearrange the file array. | |
789 | */ | |
790 | skb = skb_dequeue(head); | |
791 | while (skb) { | |
792 | struct scm_fp_list *fp; | |
793 | ||
794 | fp = UNIXCB(skb).fp; | |
795 | for (i = 0; i < fp->count; i++) { | |
796 | int left; | |
797 | ||
798 | if (fp->fp[i] != file) | |
799 | continue; | |
800 | ||
801 | unix_notinflight(fp->user, fp->fp[i]); | |
802 | left = fp->count - 1 - i; | |
803 | if (left) { | |
804 | memmove(&fp->fp[i], &fp->fp[i + 1], | |
805 | left * sizeof(struct file *)); | |
806 | } | |
807 | fp->count--; | |
808 | if (!fp->count) { | |
809 | kfree_skb(skb); | |
810 | skb = NULL; | |
811 | } else { | |
812 | __skb_queue_tail(&list, skb); | |
813 | } | |
814 | fput(file); | |
815 | file = NULL; | |
816 | break; | |
817 | } | |
818 | ||
819 | if (!file) | |
820 | break; | |
821 | ||
822 | __skb_queue_tail(&list, skb); | |
823 | ||
824 | skb = skb_dequeue(head); | |
825 | } | |
826 | ||
827 | if (skb_peek(&list)) { | |
828 | spin_lock_irq(&head->lock); | |
829 | while ((skb = __skb_dequeue(&list)) != NULL) | |
830 | __skb_queue_tail(head, skb); | |
831 | spin_unlock_irq(&head->lock); | |
832 | } | |
73572984 JA |
833 | #endif |
834 | } | |
835 | ||
d581076b PB |
836 | static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) |
837 | { | |
838 | struct file *file = prsrc->file; | |
839 | ||
840 | if (likely(!io_file_need_scm(file))) | |
841 | fput(file); | |
842 | else | |
843 | io_rsrc_file_scm_put(ctx, file); | |
844 | } | |
845 | ||
73572984 JA |
846 | int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, |
847 | unsigned nr_args, u64 __user *tags) | |
848 | { | |
849 | __s32 __user *fds = (__s32 __user *) arg; | |
850 | struct file *file; | |
851 | int fd, ret; | |
852 | unsigned i; | |
853 | ||
854 | if (ctx->file_data) | |
855 | return -EBUSY; | |
856 | if (!nr_args) | |
857 | return -EINVAL; | |
858 | if (nr_args > IORING_MAX_FIXED_FILES) | |
859 | return -EMFILE; | |
860 | if (nr_args > rlimit(RLIMIT_NOFILE)) | |
861 | return -EMFILE; | |
fc7f3a8d | 862 | ret = io_rsrc_data_alloc(ctx, IORING_RSRC_FILE, tags, nr_args, |
73572984 JA |
863 | &ctx->file_data); |
864 | if (ret) | |
865 | return ret; | |
866 | ||
867 | if (!io_alloc_file_tables(&ctx->file_table, nr_args)) { | |
868 | io_rsrc_data_free(ctx->file_data); | |
869 | ctx->file_data = NULL; | |
870 | return -ENOMEM; | |
871 | } | |
872 | ||
873 | for (i = 0; i < nr_args; i++, ctx->nr_user_files++) { | |
874 | struct io_fixed_file *file_slot; | |
875 | ||
876 | if (fds && copy_from_user(&fd, &fds[i], sizeof(fd))) { | |
877 | ret = -EFAULT; | |
878 | goto fail; | |
879 | } | |
880 | /* allow sparse sets */ | |
881 | if (!fds || fd == -1) { | |
882 | ret = -EINVAL; | |
883 | if (unlikely(*io_get_tag_slot(ctx->file_data, i))) | |
884 | goto fail; | |
885 | continue; | |
886 | } | |
887 | ||
888 | file = fget(fd); | |
889 | ret = -EBADF; | |
890 | if (unlikely(!file)) | |
891 | goto fail; | |
892 | ||
893 | /* | |
894 | * Don't allow io_uring instances to be registered. If UNIX | |
895 | * isn't enabled, then this causes a reference cycle and this | |
896 | * instance can never get freed. If UNIX is enabled we'll | |
897 | * handle it just fine, but there's still no point in allowing | |
898 | * a ring fd as it doesn't support regular read/write anyway. | |
899 | */ | |
900 | if (io_is_uring_fops(file)) { | |
901 | fput(file); | |
902 | goto fail; | |
903 | } | |
904 | ret = io_scm_file_account(ctx, file); | |
905 | if (ret) { | |
906 | fput(file); | |
907 | goto fail; | |
908 | } | |
909 | file_slot = io_fixed_file_slot(&ctx->file_table, i); | |
910 | io_fixed_file_set(file_slot, file); | |
911 | io_file_bitmap_set(&ctx->file_table, i); | |
912 | } | |
913 | ||
6e73dffb PB |
914 | /* default it to the whole table */ |
915 | io_file_table_set_alloc_range(ctx, 0, ctx->nr_user_files); | |
73572984 JA |
916 | return 0; |
917 | fail: | |
918 | __io_sqe_files_unregister(ctx); | |
919 | return ret; | |
920 | } | |
921 | ||
922 | static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) | |
923 | { | |
924 | io_buffer_unmap(ctx, &prsrc->buf); | |
925 | prsrc->buf = NULL; | |
926 | } | |
927 | ||
928 | void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx) | |
929 | { | |
930 | unsigned int i; | |
931 | ||
932 | for (i = 0; i < ctx->nr_user_bufs; i++) | |
933 | io_buffer_unmap(ctx, &ctx->user_bufs[i]); | |
934 | kfree(ctx->user_bufs); | |
935 | io_rsrc_data_free(ctx->buf_data); | |
936 | ctx->user_bufs = NULL; | |
937 | ctx->buf_data = NULL; | |
938 | ctx->nr_user_bufs = 0; | |
939 | } | |
940 | ||
941 | int io_sqe_buffers_unregister(struct io_ring_ctx *ctx) | |
942 | { | |
943 | unsigned nr = ctx->nr_user_bufs; | |
944 | int ret; | |
945 | ||
946 | if (!ctx->buf_data) | |
947 | return -ENXIO; | |
948 | ||
949 | /* | |
950 | * Quiesce may unlock ->uring_lock, and while it's not held | |
951 | * prevent new requests using the table. | |
952 | */ | |
953 | ctx->nr_user_bufs = 0; | |
954 | ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx); | |
955 | ctx->nr_user_bufs = nr; | |
956 | if (!ret) | |
957 | __io_sqe_buffers_unregister(ctx); | |
958 | return ret; | |
959 | } | |
960 | ||
961 | /* | |
962 | * Not super efficient, but this is just a registration time. And we do cache | |
963 | * the last compound head, so generally we'll only do a full search if we don't | |
964 | * match that one. | |
965 | * | |
966 | * We check if the given compound head page has already been accounted, to | |
967 | * avoid double accounting it. This allows us to account the full size of the | |
968 | * page, not just the constituent pages of a huge page. | |
969 | */ | |
970 | static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages, | |
971 | int nr_pages, struct page *hpage) | |
972 | { | |
973 | int i, j; | |
974 | ||
975 | /* check current page array */ | |
976 | for (i = 0; i < nr_pages; i++) { | |
977 | if (!PageCompound(pages[i])) | |
978 | continue; | |
979 | if (compound_head(pages[i]) == hpage) | |
980 | return true; | |
981 | } | |
982 | ||
983 | /* check previously registered pages */ | |
984 | for (i = 0; i < ctx->nr_user_bufs; i++) { | |
985 | struct io_mapped_ubuf *imu = ctx->user_bufs[i]; | |
986 | ||
987 | for (j = 0; j < imu->nr_bvecs; j++) { | |
988 | if (!PageCompound(imu->bvec[j].bv_page)) | |
989 | continue; | |
990 | if (compound_head(imu->bvec[j].bv_page) == hpage) | |
991 | return true; | |
992 | } | |
993 | } | |
994 | ||
995 | return false; | |
996 | } | |
997 | ||
998 | static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages, | |
999 | int nr_pages, struct io_mapped_ubuf *imu, | |
1000 | struct page **last_hpage) | |
1001 | { | |
1002 | int i, ret; | |
1003 | ||
1004 | imu->acct_pages = 0; | |
1005 | for (i = 0; i < nr_pages; i++) { | |
1006 | if (!PageCompound(pages[i])) { | |
1007 | imu->acct_pages++; | |
1008 | } else { | |
1009 | struct page *hpage; | |
1010 | ||
1011 | hpage = compound_head(pages[i]); | |
1012 | if (hpage == *last_hpage) | |
1013 | continue; | |
1014 | *last_hpage = hpage; | |
1015 | if (headpage_already_acct(ctx, pages, i, hpage)) | |
1016 | continue; | |
1017 | imu->acct_pages += page_size(hpage) >> PAGE_SHIFT; | |
1018 | } | |
1019 | } | |
1020 | ||
1021 | if (!imu->acct_pages) | |
1022 | return 0; | |
1023 | ||
1024 | ret = io_account_mem(ctx, imu->acct_pages); | |
1025 | if (ret) | |
1026 | imu->acct_pages = 0; | |
1027 | return ret; | |
1028 | } | |
1029 | ||
1030 | struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages) | |
1031 | { | |
1032 | unsigned long start, end, nr_pages; | |
73572984 | 1033 | struct page **pages = NULL; |
34ed8d0d | 1034 | int pret, ret = -ENOMEM; |
73572984 JA |
1035 | |
1036 | end = (ubuf + len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
1037 | start = ubuf >> PAGE_SHIFT; | |
1038 | nr_pages = end - start; | |
1039 | ||
1040 | pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL); | |
1041 | if (!pages) | |
1042 | goto done; | |
1043 | ||
73572984 JA |
1044 | ret = 0; |
1045 | mmap_read_lock(current->mm); | |
1046 | pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM, | |
4c630f30 | 1047 | pages); |
34ed8d0d | 1048 | if (pret == nr_pages) |
73572984 | 1049 | *npages = nr_pages; |
34ed8d0d | 1050 | else |
73572984 | 1051 | ret = pret < 0 ? pret : -EFAULT; |
34ed8d0d | 1052 | |
73572984 JA |
1053 | mmap_read_unlock(current->mm); |
1054 | if (ret) { | |
34ed8d0d | 1055 | /* if we did partial map, release any pages we did get */ |
73572984 JA |
1056 | if (pret > 0) |
1057 | unpin_user_pages(pages, pret); | |
1058 | goto done; | |
1059 | } | |
1060 | ret = 0; | |
1061 | done: | |
73572984 JA |
1062 | if (ret < 0) { |
1063 | kvfree(pages); | |
1064 | pages = ERR_PTR(ret); | |
1065 | } | |
1066 | return pages; | |
1067 | } | |
1068 | ||
1069 | static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, | |
1070 | struct io_mapped_ubuf **pimu, | |
1071 | struct page **last_hpage) | |
1072 | { | |
1073 | struct io_mapped_ubuf *imu = NULL; | |
1074 | struct page **pages = NULL; | |
1075 | unsigned long off; | |
1076 | size_t size; | |
1077 | int ret, nr_pages, i; | |
977bc873 | 1078 | struct folio *folio = NULL; |
73572984 | 1079 | |
5ff4fdff PB |
1080 | *pimu = ctx->dummy_ubuf; |
1081 | if (!iov->iov_base) | |
73572984 | 1082 | return 0; |
73572984 | 1083 | |
73572984 | 1084 | ret = -ENOMEM; |
73572984 JA |
1085 | pages = io_pin_pages((unsigned long) iov->iov_base, iov->iov_len, |
1086 | &nr_pages); | |
1087 | if (IS_ERR(pages)) { | |
1088 | ret = PTR_ERR(pages); | |
1089 | pages = NULL; | |
1090 | goto done; | |
1091 | } | |
1092 | ||
57bebf80 PB |
1093 | /* If it's a huge page, try to coalesce them into a single bvec entry */ |
1094 | if (nr_pages > 1) { | |
1095 | folio = page_folio(pages[0]); | |
1096 | for (i = 1; i < nr_pages; i++) { | |
776617db TH |
1097 | /* |
1098 | * Pages must be consecutive and on the same folio for | |
1099 | * this to work | |
1100 | */ | |
1101 | if (page_folio(pages[i]) != folio || | |
1102 | pages[i] != pages[i - 1] + 1) { | |
57bebf80 PB |
1103 | folio = NULL; |
1104 | break; | |
1105 | } | |
1106 | } | |
1107 | if (folio) { | |
d2acf789 PB |
1108 | /* |
1109 | * The pages are bound to the folio, it doesn't | |
1110 | * actually unpin them but drops all but one reference, | |
1111 | * which is usually put down by io_buffer_unmap(). | |
1112 | * Note, needs a better helper. | |
1113 | */ | |
1114 | unpin_user_pages(&pages[1], nr_pages - 1); | |
57bebf80 PB |
1115 | nr_pages = 1; |
1116 | } | |
1117 | } | |
1118 | ||
73572984 JA |
1119 | imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL); |
1120 | if (!imu) | |
1121 | goto done; | |
1122 | ||
1123 | ret = io_buffer_account_pin(ctx, pages, nr_pages, imu, last_hpage); | |
1124 | if (ret) { | |
1125 | unpin_user_pages(pages, nr_pages); | |
1126 | goto done; | |
1127 | } | |
1128 | ||
1129 | off = (unsigned long) iov->iov_base & ~PAGE_MASK; | |
1130 | size = iov->iov_len; | |
57bebf80 PB |
1131 | /* store original address for later verification */ |
1132 | imu->ubuf = (unsigned long) iov->iov_base; | |
1133 | imu->ubuf_end = imu->ubuf + iov->iov_len; | |
1134 | imu->nr_bvecs = nr_pages; | |
1135 | *pimu = imu; | |
1136 | ret = 0; | |
1137 | ||
1138 | if (folio) { | |
1139 | bvec_set_page(&imu->bvec[0], pages[0], size, off); | |
1140 | goto done; | |
1141 | } | |
73572984 JA |
1142 | for (i = 0; i < nr_pages; i++) { |
1143 | size_t vec_len; | |
1144 | ||
1145 | vec_len = min_t(size_t, size, PAGE_SIZE - off); | |
cc342a21 | 1146 | bvec_set_page(&imu->bvec[i], pages[i], vec_len, off); |
73572984 JA |
1147 | off = 0; |
1148 | size -= vec_len; | |
1149 | } | |
73572984 JA |
1150 | done: |
1151 | if (ret) | |
1152 | kvfree(imu); | |
1153 | kvfree(pages); | |
1154 | return ret; | |
1155 | } | |
1156 | ||
1157 | static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args) | |
1158 | { | |
1159 | ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL); | |
1160 | return ctx->user_bufs ? 0 : -ENOMEM; | |
1161 | } | |
1162 | ||
1163 | int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg, | |
1164 | unsigned int nr_args, u64 __user *tags) | |
1165 | { | |
1166 | struct page *last_hpage = NULL; | |
1167 | struct io_rsrc_data *data; | |
1168 | int i, ret; | |
1169 | struct iovec iov; | |
1170 | ||
1171 | BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16)); | |
1172 | ||
1173 | if (ctx->user_bufs) | |
1174 | return -EBUSY; | |
1175 | if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS) | |
1176 | return -EINVAL; | |
fc7f3a8d | 1177 | ret = io_rsrc_data_alloc(ctx, IORING_RSRC_BUFFER, tags, nr_args, &data); |
73572984 JA |
1178 | if (ret) |
1179 | return ret; | |
1180 | ret = io_buffers_map_alloc(ctx, nr_args); | |
1181 | if (ret) { | |
1182 | io_rsrc_data_free(data); | |
1183 | return ret; | |
1184 | } | |
1185 | ||
1186 | for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) { | |
1187 | if (arg) { | |
1188 | ret = io_copy_iov(ctx, &iov, arg, i); | |
1189 | if (ret) | |
1190 | break; | |
1191 | ret = io_buffer_validate(&iov); | |
1192 | if (ret) | |
1193 | break; | |
1194 | } else { | |
1195 | memset(&iov, 0, sizeof(iov)); | |
1196 | } | |
1197 | ||
1198 | if (!iov.iov_base && *io_get_tag_slot(data, i)) { | |
1199 | ret = -EINVAL; | |
1200 | break; | |
1201 | } | |
1202 | ||
1203 | ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i], | |
1204 | &last_hpage); | |
1205 | if (ret) | |
1206 | break; | |
1207 | } | |
1208 | ||
1209 | WARN_ON_ONCE(ctx->buf_data); | |
1210 | ||
1211 | ctx->buf_data = data; | |
1212 | if (ret) | |
1213 | __io_sqe_buffers_unregister(ctx); | |
73572984 JA |
1214 | return ret; |
1215 | } | |
c059f785 PB |
1216 | |
1217 | int io_import_fixed(int ddir, struct iov_iter *iter, | |
1218 | struct io_mapped_ubuf *imu, | |
1219 | u64 buf_addr, size_t len) | |
1220 | { | |
1221 | u64 buf_end; | |
1222 | size_t offset; | |
1223 | ||
1224 | if (WARN_ON_ONCE(!imu)) | |
1225 | return -EFAULT; | |
1226 | if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end))) | |
1227 | return -EFAULT; | |
1228 | /* not inside the mapped region */ | |
1229 | if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end)) | |
1230 | return -EFAULT; | |
1231 | ||
1232 | /* | |
6bf65a1b | 1233 | * Might not be a start of buffer, set size appropriately |
c059f785 PB |
1234 | * and advance us to the beginning. |
1235 | */ | |
1236 | offset = buf_addr - imu->ubuf; | |
1237 | iov_iter_bvec(iter, ddir, imu->bvec, imu->nr_bvecs, offset + len); | |
1238 | ||
1239 | if (offset) { | |
1240 | /* | |
1241 | * Don't use iov_iter_advance() here, as it's really slow for | |
1242 | * using the latter parts of a big fixed buffer - it iterates | |
1243 | * over each segment manually. We can cheat a bit here, because | |
1244 | * we know that: | |
1245 | * | |
1246 | * 1) it's a BVEC iter, we set it up | |
1247 | * 2) all bvecs are PAGE_SIZE in size, except potentially the | |
1248 | * first and last bvec | |
1249 | * | |
1250 | * So just find our index, and adjust the iterator afterwards. | |
1251 | * If the offset is within the first bvec (or the whole first | |
1252 | * bvec, just use iov_iter_advance(). This makes it easier | |
1253 | * since we can just skip the first segment, which may not | |
1254 | * be PAGE_SIZE aligned. | |
1255 | */ | |
1256 | const struct bio_vec *bvec = imu->bvec; | |
1257 | ||
1258 | if (offset <= bvec->bv_len) { | |
57bebf80 PB |
1259 | /* |
1260 | * Note, huge pages buffers consists of one large | |
1261 | * bvec entry and should always go this way. The other | |
1262 | * branch doesn't expect non PAGE_SIZE'd chunks. | |
1263 | */ | |
b000ae0e PB |
1264 | iter->bvec = bvec; |
1265 | iter->nr_segs = bvec->bv_len; | |
1266 | iter->count -= offset; | |
1267 | iter->iov_offset = offset; | |
c059f785 PB |
1268 | } else { |
1269 | unsigned long seg_skip; | |
1270 | ||
1271 | /* skip first vec */ | |
1272 | offset -= bvec->bv_len; | |
1273 | seg_skip = 1 + (offset >> PAGE_SHIFT); | |
1274 | ||
1275 | iter->bvec = bvec + seg_skip; | |
1276 | iter->nr_segs -= seg_skip; | |
1277 | iter->count -= bvec->bv_len + offset; | |
1278 | iter->iov_offset = offset & ~PAGE_MASK; | |
1279 | } | |
1280 | } | |
1281 | ||
1282 | return 0; | |
1283 | } |