Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * An async IO implementation for Linux | |
3 | * Written by Benjamin LaHaise <bcrl@kvack.org> | |
4 | * | |
5 | * Implements an efficient asynchronous io interface. | |
6 | * | |
7 | * Copyright 2000, 2001, 2002 Red Hat, Inc. All Rights Reserved. | |
bfe4037e | 8 | * Copyright 2018 Christoph Hellwig. |
1da177e4 LT |
9 | * |
10 | * See ../COPYING for licensing terms. | |
11 | */ | |
caf4167a KO |
12 | #define pr_fmt(fmt) "%s: " fmt, __func__ |
13 | ||
1da177e4 LT |
14 | #include <linux/kernel.h> |
15 | #include <linux/init.h> | |
16 | #include <linux/errno.h> | |
17 | #include <linux/time.h> | |
18 | #include <linux/aio_abi.h> | |
630d9c47 | 19 | #include <linux/export.h> |
1da177e4 | 20 | #include <linux/syscalls.h> |
b9d128f1 | 21 | #include <linux/backing-dev.h> |
9018ccc4 | 22 | #include <linux/refcount.h> |
027445c3 | 23 | #include <linux/uio.h> |
1da177e4 | 24 | |
174cd4b1 | 25 | #include <linux/sched/signal.h> |
1da177e4 LT |
26 | #include <linux/fs.h> |
27 | #include <linux/file.h> | |
28 | #include <linux/mm.h> | |
29 | #include <linux/mman.h> | |
e1bdd5f2 | 30 | #include <linux/percpu.h> |
1da177e4 LT |
31 | #include <linux/slab.h> |
32 | #include <linux/timer.h> | |
33 | #include <linux/aio.h> | |
34 | #include <linux/highmem.h> | |
35 | #include <linux/workqueue.h> | |
36 | #include <linux/security.h> | |
9c3060be | 37 | #include <linux/eventfd.h> |
cfb1e33e | 38 | #include <linux/blkdev.h> |
9d85cba7 | 39 | #include <linux/compat.h> |
36bc08cc GZ |
40 | #include <linux/migrate.h> |
41 | #include <linux/ramfs.h> | |
723be6e3 | 42 | #include <linux/percpu-refcount.h> |
71ad7490 | 43 | #include <linux/mount.h> |
52db59df | 44 | #include <linux/pseudo_fs.h> |
1da177e4 | 45 | |
7c0f6ba6 | 46 | #include <linux/uaccess.h> |
a538e3ff | 47 | #include <linux/nospec.h> |
1da177e4 | 48 | |
68d70d03 AV |
49 | #include "internal.h" |
50 | ||
f3a2752a CH |
51 | #define KIOCB_KEY 0 |
52 | ||
4e179bca KO |
53 | #define AIO_RING_MAGIC 0xa10a10a1 |
54 | #define AIO_RING_COMPAT_FEATURES 1 | |
55 | #define AIO_RING_INCOMPAT_FEATURES 0 | |
56 | struct aio_ring { | |
57 | unsigned id; /* kernel internal index number */ | |
58 | unsigned nr; /* number of io_events */ | |
fa8a53c3 BL |
59 | unsigned head; /* Written to by userland or under ring_lock |
60 | * mutex by aio_read_events_ring(). */ | |
4e179bca KO |
61 | unsigned tail; |
62 | ||
63 | unsigned magic; | |
64 | unsigned compat_features; | |
65 | unsigned incompat_features; | |
66 | unsigned header_length; /* size of aio_ring */ | |
67 | ||
68 | ||
241cb28e | 69 | struct io_event io_events[]; |
4e179bca KO |
70 | }; /* 128 bytes + ring size */ |
71 | ||
a79d40e9 JA |
72 | /* |
73 | * Plugging is meant to work with larger batches of IOs. If we don't | |
74 | * have more than the below, then don't bother setting up a plug. | |
75 | */ | |
76 | #define AIO_PLUG_THRESHOLD 2 | |
77 | ||
4e179bca | 78 | #define AIO_RING_PAGES 8 |
4e179bca | 79 | |
db446a08 | 80 | struct kioctx_table { |
d0264c01 TH |
81 | struct rcu_head rcu; |
82 | unsigned nr; | |
db7fcc88 | 83 | struct kioctx __rcu *table[] __counted_by(nr); |
db446a08 BL |
84 | }; |
85 | ||
e1bdd5f2 KO |
86 | struct kioctx_cpu { |
87 | unsigned reqs_available; | |
88 | }; | |
89 | ||
dc48e56d JA |
90 | struct ctx_rq_wait { |
91 | struct completion comp; | |
92 | atomic_t count; | |
93 | }; | |
94 | ||
4e179bca | 95 | struct kioctx { |
723be6e3 | 96 | struct percpu_ref users; |
36f55889 | 97 | atomic_t dead; |
4e179bca | 98 | |
e34ecee2 KO |
99 | struct percpu_ref reqs; |
100 | ||
4e179bca | 101 | unsigned long user_id; |
4e179bca | 102 | |
6c203968 | 103 | struct kioctx_cpu __percpu *cpu; |
e1bdd5f2 KO |
104 | |
105 | /* | |
106 | * For percpu reqs_available, number of slots we move to/from global | |
107 | * counter at a time: | |
108 | */ | |
109 | unsigned req_batch; | |
3e845ce0 KO |
110 | /* |
111 | * This is what userspace passed to io_setup(), it's not used for | |
112 | * anything but counting against the global max_reqs quota. | |
113 | * | |
58c85dc2 | 114 | * The real limit is nr_events - 1, which will be larger (see |
3e845ce0 KO |
115 | * aio_setup_ring()) |
116 | */ | |
4e179bca KO |
117 | unsigned max_reqs; |
118 | ||
58c85dc2 KO |
119 | /* Size of ringbuffer, in units of struct io_event */ |
120 | unsigned nr_events; | |
4e179bca | 121 | |
58c85dc2 KO |
122 | unsigned long mmap_base; |
123 | unsigned long mmap_size; | |
124 | ||
16594e60 | 125 | struct folio **ring_folios; |
58c85dc2 KO |
126 | long nr_pages; |
127 | ||
f729863a | 128 | struct rcu_work free_rwork; /* see free_ioctx() */ |
4e23bcae | 129 | |
e02ba72a AP |
130 | /* |
131 | * signals when all in-flight requests are done | |
132 | */ | |
dc48e56d | 133 | struct ctx_rq_wait *rq_wait; |
e02ba72a | 134 | |
4e23bcae | 135 | struct { |
34e83fc6 KO |
136 | /* |
137 | * This counts the number of available slots in the ringbuffer, | |
138 | * so we avoid overflowing it: it's decremented (if positive) | |
139 | * when allocating a kiocb and incremented when the resulting | |
140 | * io_event is pulled off the ringbuffer. | |
e1bdd5f2 KO |
141 | * |
142 | * We batch accesses to it with a percpu version. | |
34e83fc6 KO |
143 | */ |
144 | atomic_t reqs_available; | |
4e23bcae KO |
145 | } ____cacheline_aligned_in_smp; |
146 | ||
147 | struct { | |
148 | spinlock_t ctx_lock; | |
149 | struct list_head active_reqs; /* used for cancellation */ | |
150 | } ____cacheline_aligned_in_smp; | |
151 | ||
58c85dc2 KO |
152 | struct { |
153 | struct mutex ring_lock; | |
4e23bcae KO |
154 | wait_queue_head_t wait; |
155 | } ____cacheline_aligned_in_smp; | |
58c85dc2 KO |
156 | |
157 | struct { | |
158 | unsigned tail; | |
d856f32a | 159 | unsigned completed_events; |
58c85dc2 | 160 | spinlock_t completion_lock; |
4e23bcae | 161 | } ____cacheline_aligned_in_smp; |
58c85dc2 | 162 | |
16594e60 | 163 | struct folio *internal_folios[AIO_RING_PAGES]; |
36bc08cc | 164 | struct file *aio_ring_file; |
db446a08 BL |
165 | |
166 | unsigned id; | |
4e179bca KO |
167 | }; |
168 | ||
84c4e1f8 LT |
169 | /* |
170 | * First field must be the file pointer in all the | |
171 | * iocb unions! See also 'struct kiocb' in <linux/fs.h> | |
172 | */ | |
a3c0d439 | 173 | struct fsync_iocb { |
a3c0d439 | 174 | struct file *file; |
84c4e1f8 | 175 | struct work_struct work; |
a3c0d439 | 176 | bool datasync; |
530f32fc | 177 | struct cred *creds; |
a3c0d439 CH |
178 | }; |
179 | ||
bfe4037e CH |
180 | struct poll_iocb { |
181 | struct file *file; | |
182 | struct wait_queue_head *head; | |
183 | __poll_t events; | |
bfe4037e | 184 | bool cancelled; |
363bee27 EB |
185 | bool work_scheduled; |
186 | bool work_need_resched; | |
bfe4037e CH |
187 | struct wait_queue_entry wait; |
188 | struct work_struct work; | |
189 | }; | |
190 | ||
84c4e1f8 LT |
191 | /* |
192 | * NOTE! Each of the iocb union members has the file pointer | |
193 | * as the first entry in their struct definition. So you can | |
194 | * access the file pointer through any of the sub-structs, | |
195 | * or directly as just 'ki_filp' in this struct. | |
196 | */ | |
04b2fa9f | 197 | struct aio_kiocb { |
54843f87 | 198 | union { |
84c4e1f8 | 199 | struct file *ki_filp; |
54843f87 | 200 | struct kiocb rw; |
a3c0d439 | 201 | struct fsync_iocb fsync; |
bfe4037e | 202 | struct poll_iocb poll; |
54843f87 | 203 | }; |
04b2fa9f CH |
204 | |
205 | struct kioctx *ki_ctx; | |
206 | kiocb_cancel_fn *ki_cancel; | |
207 | ||
a9339b78 | 208 | struct io_event ki_res; |
04b2fa9f CH |
209 | |
210 | struct list_head ki_list; /* the aio core uses this | |
211 | * for cancellation */ | |
9018ccc4 | 212 | refcount_t ki_refcnt; |
04b2fa9f CH |
213 | |
214 | /* | |
215 | * If the aio_resfd field of the userspace iocb is not zero, | |
216 | * this is the underlying eventfd context to deliver events to. | |
217 | */ | |
218 | struct eventfd_ctx *ki_eventfd; | |
219 | }; | |
220 | ||
1da177e4 | 221 | /*------ sysctl variables----*/ |
d55b5fda | 222 | static DEFINE_SPINLOCK(aio_nr_lock); |
86b12b6c XN |
223 | static unsigned long aio_nr; /* current system wide number of aio requests */ |
224 | static unsigned long aio_max_nr = 0x10000; /* system wide maximum number of aio requests */ | |
1da177e4 | 225 | /*----end sysctl variables---*/ |
86b12b6c XN |
226 | #ifdef CONFIG_SYSCTL |
227 | static struct ctl_table aio_sysctls[] = { | |
228 | { | |
229 | .procname = "aio-nr", | |
230 | .data = &aio_nr, | |
231 | .maxlen = sizeof(aio_nr), | |
232 | .mode = 0444, | |
233 | .proc_handler = proc_doulongvec_minmax, | |
234 | }, | |
235 | { | |
236 | .procname = "aio-max-nr", | |
237 | .data = &aio_max_nr, | |
238 | .maxlen = sizeof(aio_max_nr), | |
239 | .mode = 0644, | |
240 | .proc_handler = proc_doulongvec_minmax, | |
241 | }, | |
86b12b6c XN |
242 | }; |
243 | ||
244 | static void __init aio_sysctl_init(void) | |
245 | { | |
246 | register_sysctl_init("fs", aio_sysctls); | |
247 | } | |
248 | #else | |
249 | #define aio_sysctl_init() do { } while (0) | |
250 | #endif | |
1da177e4 | 251 | |
e18b890b CL |
252 | static struct kmem_cache *kiocb_cachep; |
253 | static struct kmem_cache *kioctx_cachep; | |
1da177e4 | 254 | |
71ad7490 BL |
255 | static struct vfsmount *aio_mnt; |
256 | ||
257 | static const struct file_operations aio_ring_fops; | |
258 | static const struct address_space_operations aio_ctx_aops; | |
259 | ||
260 | static struct file *aio_private_file(struct kioctx *ctx, loff_t nr_pages) | |
261 | { | |
71ad7490 | 262 | struct file *file; |
71ad7490 | 263 | struct inode *inode = alloc_anon_inode(aio_mnt->mnt_sb); |
7f62656b DC |
264 | if (IS_ERR(inode)) |
265 | return ERR_CAST(inode); | |
71ad7490 BL |
266 | |
267 | inode->i_mapping->a_ops = &aio_ctx_aops; | |
600f111e | 268 | inode->i_mapping->i_private_data = ctx; |
71ad7490 BL |
269 | inode->i_size = PAGE_SIZE * nr_pages; |
270 | ||
d93aa9d8 AV |
271 | file = alloc_file_pseudo(inode, aio_mnt, "[aio]", |
272 | O_RDWR, &aio_ring_fops); | |
c9c554f2 | 273 | if (IS_ERR(file)) |
71ad7490 | 274 | iput(inode); |
71ad7490 BL |
275 | return file; |
276 | } | |
277 | ||
52db59df | 278 | static int aio_init_fs_context(struct fs_context *fc) |
71ad7490 | 279 | { |
52db59df DH |
280 | if (!init_pseudo(fc, AIO_RING_MAGIC)) |
281 | return -ENOMEM; | |
282 | fc->s_iflags |= SB_I_NOEXEC; | |
283 | return 0; | |
71ad7490 BL |
284 | } |
285 | ||
1da177e4 LT |
286 | /* aio_setup |
287 | * Creates the slab caches used by the aio routines, panic on | |
288 | * failure as this is done early during the boot sequence. | |
289 | */ | |
290 | static int __init aio_setup(void) | |
291 | { | |
71ad7490 BL |
292 | static struct file_system_type aio_fs = { |
293 | .name = "aio", | |
52db59df | 294 | .init_fs_context = aio_init_fs_context, |
71ad7490 BL |
295 | .kill_sb = kill_anon_super, |
296 | }; | |
297 | aio_mnt = kern_mount(&aio_fs); | |
298 | if (IS_ERR(aio_mnt)) | |
299 | panic("Failed to create aio fs mount."); | |
300 | ||
04b2fa9f | 301 | kiocb_cachep = KMEM_CACHE(aio_kiocb, SLAB_HWCACHE_ALIGN|SLAB_PANIC); |
0a31bd5f | 302 | kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC); |
86b12b6c | 303 | aio_sysctl_init(); |
1da177e4 LT |
304 | return 0; |
305 | } | |
385773e0 | 306 | __initcall(aio_setup); |
1da177e4 | 307 | |
5e9ae2e5 BL |
308 | static void put_aio_ring_file(struct kioctx *ctx) |
309 | { | |
310 | struct file *aio_ring_file = ctx->aio_ring_file; | |
de04e769 RV |
311 | struct address_space *i_mapping; |
312 | ||
5e9ae2e5 | 313 | if (aio_ring_file) { |
45063097 | 314 | truncate_setsize(file_inode(aio_ring_file), 0); |
5e9ae2e5 BL |
315 | |
316 | /* Prevent further access to the kioctx from migratepages */ | |
45063097 | 317 | i_mapping = aio_ring_file->f_mapping; |
600f111e MWO |
318 | spin_lock(&i_mapping->i_private_lock); |
319 | i_mapping->i_private_data = NULL; | |
5e9ae2e5 | 320 | ctx->aio_ring_file = NULL; |
600f111e | 321 | spin_unlock(&i_mapping->i_private_lock); |
5e9ae2e5 BL |
322 | |
323 | fput(aio_ring_file); | |
324 | } | |
325 | } | |
326 | ||
1da177e4 LT |
327 | static void aio_free_ring(struct kioctx *ctx) |
328 | { | |
36bc08cc | 329 | int i; |
1da177e4 | 330 | |
fa8a53c3 BL |
331 | /* Disconnect the kiotx from the ring file. This prevents future |
332 | * accesses to the kioctx from page migration. | |
333 | */ | |
334 | put_aio_ring_file(ctx); | |
335 | ||
36bc08cc | 336 | for (i = 0; i < ctx->nr_pages; i++) { |
16594e60 | 337 | struct folio *folio = ctx->ring_folios[i]; |
5ea0a355 KW |
338 | |
339 | if (!folio) | |
8e321fef | 340 | continue; |
5ea0a355 KW |
341 | |
342 | pr_debug("pid(%d) [%d] folio->count=%d\n", current->pid, i, | |
343 | folio_ref_count(folio)); | |
16594e60 | 344 | ctx->ring_folios[i] = NULL; |
5ea0a355 | 345 | folio_put(folio); |
36bc08cc | 346 | } |
1da177e4 | 347 | |
16594e60 KW |
348 | if (ctx->ring_folios && ctx->ring_folios != ctx->internal_folios) { |
349 | kfree(ctx->ring_folios); | |
350 | ctx->ring_folios = NULL; | |
ddb8c45b | 351 | } |
36bc08cc GZ |
352 | } |
353 | ||
14d07113 | 354 | static int aio_ring_mremap(struct vm_area_struct *vma) |
e4a0d3e7 | 355 | { |
5477e70a | 356 | struct file *file = vma->vm_file; |
e4a0d3e7 PE |
357 | struct mm_struct *mm = vma->vm_mm; |
358 | struct kioctx_table *table; | |
b2edffdd | 359 | int i, res = -EINVAL; |
e4a0d3e7 PE |
360 | |
361 | spin_lock(&mm->ioctx_lock); | |
362 | rcu_read_lock(); | |
363 | table = rcu_dereference(mm->ioctx_table); | |
81e9d6f8 SJ |
364 | if (!table) |
365 | goto out_unlock; | |
366 | ||
e4a0d3e7 PE |
367 | for (i = 0; i < table->nr; i++) { |
368 | struct kioctx *ctx; | |
369 | ||
d0264c01 | 370 | ctx = rcu_dereference(table->table[i]); |
e4a0d3e7 | 371 | if (ctx && ctx->aio_ring_file == file) { |
b2edffdd AV |
372 | if (!atomic_read(&ctx->dead)) { |
373 | ctx->user_id = ctx->mmap_base = vma->vm_start; | |
374 | res = 0; | |
375 | } | |
e4a0d3e7 PE |
376 | break; |
377 | } | |
378 | } | |
379 | ||
81e9d6f8 | 380 | out_unlock: |
e4a0d3e7 PE |
381 | rcu_read_unlock(); |
382 | spin_unlock(&mm->ioctx_lock); | |
b2edffdd | 383 | return res; |
e4a0d3e7 PE |
384 | } |
385 | ||
5477e70a ON |
386 | static const struct vm_operations_struct aio_ring_vm_ops = { |
387 | .mremap = aio_ring_mremap, | |
388 | #if IS_ENABLED(CONFIG_MMU) | |
389 | .fault = filemap_fault, | |
390 | .map_pages = filemap_map_pages, | |
391 | .page_mkwrite = filemap_page_mkwrite, | |
392 | #endif | |
393 | }; | |
394 | ||
395 | static int aio_ring_mmap(struct file *file, struct vm_area_struct *vma) | |
396 | { | |
1c71222e | 397 | vm_flags_set(vma, VM_DONTEXPAND); |
5477e70a ON |
398 | vma->vm_ops = &aio_ring_vm_ops; |
399 | return 0; | |
400 | } | |
401 | ||
36bc08cc GZ |
402 | static const struct file_operations aio_ring_fops = { |
403 | .mmap = aio_ring_mmap, | |
404 | }; | |
405 | ||
0c45355f | 406 | #if IS_ENABLED(CONFIG_MIGRATION) |
3648951c MWO |
407 | static int aio_migrate_folio(struct address_space *mapping, struct folio *dst, |
408 | struct folio *src, enum migrate_mode mode) | |
36bc08cc | 409 | { |
5e9ae2e5 | 410 | struct kioctx *ctx; |
36bc08cc | 411 | unsigned long flags; |
fa8a53c3 | 412 | pgoff_t idx; |
90663284 | 413 | int rc = 0; |
8e321fef | 414 | |
600f111e MWO |
415 | /* mapping->i_private_lock here protects against the kioctx teardown. */ |
416 | spin_lock(&mapping->i_private_lock); | |
417 | ctx = mapping->i_private_data; | |
fa8a53c3 BL |
418 | if (!ctx) { |
419 | rc = -EINVAL; | |
420 | goto out; | |
421 | } | |
422 | ||
423 | /* The ring_lock mutex. The prevents aio_read_events() from writing | |
424 | * to the ring's head, and prevents page migration from mucking in | |
425 | * a partially initialized kiotx. | |
426 | */ | |
427 | if (!mutex_trylock(&ctx->ring_lock)) { | |
428 | rc = -EAGAIN; | |
429 | goto out; | |
430 | } | |
431 | ||
3648951c | 432 | idx = src->index; |
fa8a53c3 | 433 | if (idx < (pgoff_t)ctx->nr_pages) { |
3648951c | 434 | /* Make sure the old folio hasn't already been changed */ |
16594e60 | 435 | if (ctx->ring_folios[idx] != src) |
fa8a53c3 | 436 | rc = -EAGAIN; |
8e321fef BL |
437 | } else |
438 | rc = -EINVAL; | |
8e321fef BL |
439 | |
440 | if (rc != 0) | |
fa8a53c3 | 441 | goto out_unlock; |
8e321fef | 442 | |
36bc08cc | 443 | /* Writeback must be complete */ |
3648951c MWO |
444 | BUG_ON(folio_test_writeback(src)); |
445 | folio_get(dst); | |
36bc08cc | 446 | |
3648951c | 447 | rc = folio_migrate_mapping(mapping, dst, src, 1); |
36bc08cc | 448 | if (rc != MIGRATEPAGE_SUCCESS) { |
3648951c | 449 | folio_put(dst); |
fa8a53c3 | 450 | goto out_unlock; |
36bc08cc GZ |
451 | } |
452 | ||
fa8a53c3 | 453 | /* Take completion_lock to prevent other writes to the ring buffer |
3648951c | 454 | * while the old folio is copied to the new. This prevents new |
fa8a53c3 | 455 | * events from being lost. |
5e9ae2e5 | 456 | */ |
fa8a53c3 | 457 | spin_lock_irqsave(&ctx->completion_lock, flags); |
3f594937 KW |
458 | folio_copy(dst, src); |
459 | folio_migrate_flags(dst, src); | |
16594e60 KW |
460 | BUG_ON(ctx->ring_folios[idx] != src); |
461 | ctx->ring_folios[idx] = dst; | |
fa8a53c3 | 462 | spin_unlock_irqrestore(&ctx->completion_lock, flags); |
36bc08cc | 463 | |
3648951c MWO |
464 | /* The old folio is no longer accessible. */ |
465 | folio_put(src); | |
8e321fef | 466 | |
fa8a53c3 BL |
467 | out_unlock: |
468 | mutex_unlock(&ctx->ring_lock); | |
469 | out: | |
600f111e | 470 | spin_unlock(&mapping->i_private_lock); |
36bc08cc | 471 | return rc; |
1da177e4 | 472 | } |
3648951c MWO |
473 | #else |
474 | #define aio_migrate_folio NULL | |
0c45355f | 475 | #endif |
1da177e4 | 476 | |
36bc08cc | 477 | static const struct address_space_operations aio_ctx_aops = { |
46de8b97 | 478 | .dirty_folio = noop_dirty_folio, |
3648951c | 479 | .migrate_folio = aio_migrate_folio, |
36bc08cc GZ |
480 | }; |
481 | ||
2a8a9867 | 482 | static int aio_setup_ring(struct kioctx *ctx, unsigned int nr_events) |
1da177e4 LT |
483 | { |
484 | struct aio_ring *ring; | |
41003a7b | 485 | struct mm_struct *mm = current->mm; |
3dc9acb6 | 486 | unsigned long size, unused; |
1da177e4 | 487 | int nr_pages; |
36bc08cc GZ |
488 | int i; |
489 | struct file *file; | |
1da177e4 LT |
490 | |
491 | /* Compensate for the ring buffer's head/tail overlap entry */ | |
492 | nr_events += 2; /* 1 is required, 2 for good luck */ | |
493 | ||
494 | size = sizeof(struct aio_ring); | |
495 | size += sizeof(struct io_event) * nr_events; | |
1da177e4 | 496 | |
36bc08cc | 497 | nr_pages = PFN_UP(size); |
1da177e4 LT |
498 | if (nr_pages < 0) |
499 | return -EINVAL; | |
500 | ||
71ad7490 | 501 | file = aio_private_file(ctx, nr_pages); |
36bc08cc GZ |
502 | if (IS_ERR(file)) { |
503 | ctx->aio_ring_file = NULL; | |
fa8a53c3 | 504 | return -ENOMEM; |
36bc08cc GZ |
505 | } |
506 | ||
3dc9acb6 LT |
507 | ctx->aio_ring_file = file; |
508 | nr_events = (PAGE_SIZE * nr_pages - sizeof(struct aio_ring)) | |
509 | / sizeof(struct io_event); | |
510 | ||
16594e60 | 511 | ctx->ring_folios = ctx->internal_folios; |
3dc9acb6 | 512 | if (nr_pages > AIO_RING_PAGES) { |
16594e60 KW |
513 | ctx->ring_folios = kcalloc(nr_pages, sizeof(struct folio *), |
514 | GFP_KERNEL); | |
515 | if (!ctx->ring_folios) { | |
3dc9acb6 LT |
516 | put_aio_ring_file(ctx); |
517 | return -ENOMEM; | |
518 | } | |
519 | } | |
520 | ||
36bc08cc | 521 | for (i = 0; i < nr_pages; i++) { |
75a07b55 KW |
522 | struct folio *folio; |
523 | ||
524 | folio = __filemap_get_folio(file->f_mapping, i, | |
525 | FGP_LOCK | FGP_ACCESSED | FGP_CREAT, | |
526 | GFP_USER | __GFP_ZERO); | |
527 | if (IS_ERR(folio)) | |
36bc08cc | 528 | break; |
3dc9acb6 | 529 | |
75a07b55 KW |
530 | pr_debug("pid(%d) [%d] folio->count=%d\n", current->pid, i, |
531 | folio_ref_count(folio)); | |
532 | folio_end_read(folio, true); | |
533 | ||
16594e60 | 534 | ctx->ring_folios[i] = folio; |
36bc08cc | 535 | } |
3dc9acb6 | 536 | ctx->nr_pages = i; |
1da177e4 | 537 | |
3dc9acb6 LT |
538 | if (unlikely(i != nr_pages)) { |
539 | aio_free_ring(ctx); | |
fa8a53c3 | 540 | return -ENOMEM; |
1da177e4 LT |
541 | } |
542 | ||
58c85dc2 KO |
543 | ctx->mmap_size = nr_pages * PAGE_SIZE; |
544 | pr_debug("attempting mmap of %lu bytes\n", ctx->mmap_size); | |
36bc08cc | 545 | |
d8ed45c5 | 546 | if (mmap_write_lock_killable(mm)) { |
013373e8 MH |
547 | ctx->mmap_size = 0; |
548 | aio_free_ring(ctx); | |
549 | return -EINTR; | |
550 | } | |
551 | ||
45e55300 PC |
552 | ctx->mmap_base = do_mmap(ctx->aio_ring_file, 0, ctx->mmap_size, |
553 | PROT_READ | PROT_WRITE, | |
592b5fad | 554 | MAP_SHARED, 0, 0, &unused, NULL); |
d8ed45c5 | 555 | mmap_write_unlock(mm); |
58c85dc2 | 556 | if (IS_ERR((void *)ctx->mmap_base)) { |
58c85dc2 | 557 | ctx->mmap_size = 0; |
1da177e4 | 558 | aio_free_ring(ctx); |
fa8a53c3 | 559 | return -ENOMEM; |
1da177e4 LT |
560 | } |
561 | ||
58c85dc2 | 562 | pr_debug("mmap address: 0x%08lx\n", ctx->mmap_base); |
d6c355c7 | 563 | |
58c85dc2 KO |
564 | ctx->user_id = ctx->mmap_base; |
565 | ctx->nr_events = nr_events; /* trusted copy */ | |
1da177e4 | 566 | |
16594e60 | 567 | ring = folio_address(ctx->ring_folios[0]); |
1da177e4 | 568 | ring->nr = nr_events; /* user copy */ |
db446a08 | 569 | ring->id = ~0U; |
1da177e4 LT |
570 | ring->head = ring->tail = 0; |
571 | ring->magic = AIO_RING_MAGIC; | |
572 | ring->compat_features = AIO_RING_COMPAT_FEATURES; | |
573 | ring->incompat_features = AIO_RING_INCOMPAT_FEATURES; | |
574 | ring->header_length = sizeof(struct aio_ring); | |
16594e60 | 575 | flush_dcache_folio(ctx->ring_folios[0]); |
1da177e4 LT |
576 | |
577 | return 0; | |
578 | } | |
579 | ||
1da177e4 LT |
580 | #define AIO_EVENTS_PER_PAGE (PAGE_SIZE / sizeof(struct io_event)) |
581 | #define AIO_EVENTS_FIRST_PAGE ((PAGE_SIZE - sizeof(struct aio_ring)) / sizeof(struct io_event)) | |
582 | #define AIO_EVENTS_OFFSET (AIO_EVENTS_PER_PAGE - AIO_EVENTS_FIRST_PAGE) | |
583 | ||
04b2fa9f | 584 | void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel) |
0460fef2 | 585 | { |
961ebd12 BVA |
586 | struct aio_kiocb *req; |
587 | struct kioctx *ctx; | |
0460fef2 KO |
588 | unsigned long flags; |
589 | ||
b820de74 BVA |
590 | /* |
591 | * kiocb didn't come from aio or is neither a read nor a write, hence | |
592 | * ignore it. | |
593 | */ | |
594 | if (!(iocb->ki_flags & IOCB_AIO_RW)) | |
595 | return; | |
596 | ||
961ebd12 BVA |
597 | req = container_of(iocb, struct aio_kiocb, rw); |
598 | ||
75321b50 CH |
599 | if (WARN_ON_ONCE(!list_empty(&req->ki_list))) |
600 | return; | |
0460fef2 | 601 | |
961ebd12 BVA |
602 | ctx = req->ki_ctx; |
603 | ||
75321b50 CH |
604 | spin_lock_irqsave(&ctx->ctx_lock, flags); |
605 | list_add_tail(&req->ki_list, &ctx->active_reqs); | |
0460fef2 | 606 | req->ki_cancel = cancel; |
0460fef2 KO |
607 | spin_unlock_irqrestore(&ctx->ctx_lock, flags); |
608 | } | |
609 | EXPORT_SYMBOL(kiocb_set_cancel_fn); | |
610 | ||
a6d7cff4 TH |
611 | /* |
612 | * free_ioctx() should be RCU delayed to synchronize against the RCU | |
613 | * protected lookup_ioctx() and also needs process context to call | |
f729863a | 614 | * aio_free_ring(). Use rcu_work. |
a6d7cff4 | 615 | */ |
e34ecee2 | 616 | static void free_ioctx(struct work_struct *work) |
36f55889 | 617 | { |
f729863a TH |
618 | struct kioctx *ctx = container_of(to_rcu_work(work), struct kioctx, |
619 | free_rwork); | |
e34ecee2 | 620 | pr_debug("freeing %p\n", ctx); |
e1bdd5f2 | 621 | |
e34ecee2 | 622 | aio_free_ring(ctx); |
e1bdd5f2 | 623 | free_percpu(ctx->cpu); |
9a1049da TH |
624 | percpu_ref_exit(&ctx->reqs); |
625 | percpu_ref_exit(&ctx->users); | |
36f55889 KO |
626 | kmem_cache_free(kioctx_cachep, ctx); |
627 | } | |
628 | ||
e34ecee2 KO |
629 | static void free_ioctx_reqs(struct percpu_ref *ref) |
630 | { | |
631 | struct kioctx *ctx = container_of(ref, struct kioctx, reqs); | |
632 | ||
e02ba72a | 633 | /* At this point we know that there are no any in-flight requests */ |
dc48e56d JA |
634 | if (ctx->rq_wait && atomic_dec_and_test(&ctx->rq_wait->count)) |
635 | complete(&ctx->rq_wait->comp); | |
e02ba72a | 636 | |
a6d7cff4 | 637 | /* Synchronize against RCU protected table->table[] dereferences */ |
f729863a TH |
638 | INIT_RCU_WORK(&ctx->free_rwork, free_ioctx); |
639 | queue_rcu_work(system_wq, &ctx->free_rwork); | |
e34ecee2 KO |
640 | } |
641 | ||
36f55889 KO |
642 | /* |
643 | * When this function runs, the kioctx has been removed from the "hash table" | |
644 | * and ctx->users has dropped to 0, so we know no more kiocbs can be submitted - | |
645 | * now it's safe to cancel any that need to be. | |
646 | */ | |
e34ecee2 | 647 | static void free_ioctx_users(struct percpu_ref *ref) |
36f55889 | 648 | { |
e34ecee2 | 649 | struct kioctx *ctx = container_of(ref, struct kioctx, users); |
04b2fa9f | 650 | struct aio_kiocb *req; |
36f55889 KO |
651 | |
652 | spin_lock_irq(&ctx->ctx_lock); | |
653 | ||
654 | while (!list_empty(&ctx->active_reqs)) { | |
655 | req = list_first_entry(&ctx->active_reqs, | |
04b2fa9f | 656 | struct aio_kiocb, ki_list); |
888933f8 | 657 | req->ki_cancel(&req->rw); |
4faa9996 | 658 | list_del_init(&req->ki_list); |
36f55889 KO |
659 | } |
660 | ||
661 | spin_unlock_irq(&ctx->ctx_lock); | |
662 | ||
e34ecee2 KO |
663 | percpu_ref_kill(&ctx->reqs); |
664 | percpu_ref_put(&ctx->reqs); | |
36f55889 KO |
665 | } |
666 | ||
db446a08 BL |
667 | static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm) |
668 | { | |
669 | unsigned i, new_nr; | |
670 | struct kioctx_table *table, *old; | |
671 | struct aio_ring *ring; | |
672 | ||
673 | spin_lock(&mm->ioctx_lock); | |
855ef0de | 674 | table = rcu_dereference_raw(mm->ioctx_table); |
db446a08 BL |
675 | |
676 | while (1) { | |
677 | if (table) | |
678 | for (i = 0; i < table->nr; i++) | |
d0264c01 | 679 | if (!rcu_access_pointer(table->table[i])) { |
db446a08 | 680 | ctx->id = i; |
d0264c01 | 681 | rcu_assign_pointer(table->table[i], ctx); |
db446a08 BL |
682 | spin_unlock(&mm->ioctx_lock); |
683 | ||
fa8a53c3 BL |
684 | /* While kioctx setup is in progress, |
685 | * we are protected from page migration | |
16594e60 | 686 | * changes ring_folios by ->ring_lock. |
fa8a53c3 | 687 | */ |
16594e60 | 688 | ring = folio_address(ctx->ring_folios[0]); |
db446a08 | 689 | ring->id = ctx->id; |
db446a08 BL |
690 | return 0; |
691 | } | |
692 | ||
693 | new_nr = (table ? table->nr : 1) * 4; | |
db446a08 BL |
694 | spin_unlock(&mm->ioctx_lock); |
695 | ||
6446c4fb | 696 | table = kzalloc(struct_size(table, table, new_nr), GFP_KERNEL); |
db446a08 BL |
697 | if (!table) |
698 | return -ENOMEM; | |
699 | ||
700 | table->nr = new_nr; | |
701 | ||
702 | spin_lock(&mm->ioctx_lock); | |
855ef0de | 703 | old = rcu_dereference_raw(mm->ioctx_table); |
db446a08 BL |
704 | |
705 | if (!old) { | |
706 | rcu_assign_pointer(mm->ioctx_table, table); | |
707 | } else if (table->nr > old->nr) { | |
708 | memcpy(table->table, old->table, | |
709 | old->nr * sizeof(struct kioctx *)); | |
710 | ||
711 | rcu_assign_pointer(mm->ioctx_table, table); | |
712 | kfree_rcu(old, rcu); | |
713 | } else { | |
714 | kfree(table); | |
715 | table = old; | |
716 | } | |
717 | } | |
718 | } | |
719 | ||
e34ecee2 KO |
720 | static void aio_nr_sub(unsigned nr) |
721 | { | |
722 | spin_lock(&aio_nr_lock); | |
723 | if (WARN_ON(aio_nr - nr > aio_nr)) | |
724 | aio_nr = 0; | |
725 | else | |
726 | aio_nr -= nr; | |
727 | spin_unlock(&aio_nr_lock); | |
728 | } | |
729 | ||
1da177e4 LT |
730 | /* ioctx_alloc |
731 | * Allocates and initializes an ioctx. Returns an ERR_PTR if it failed. | |
732 | */ | |
733 | static struct kioctx *ioctx_alloc(unsigned nr_events) | |
734 | { | |
41003a7b | 735 | struct mm_struct *mm = current->mm; |
1da177e4 | 736 | struct kioctx *ctx; |
e23754f8 | 737 | int err = -ENOMEM; |
1da177e4 | 738 | |
2a8a9867 MFO |
739 | /* |
740 | * Store the original nr_events -- what userspace passed to io_setup(), | |
741 | * for counting against the global limit -- before it changes. | |
742 | */ | |
743 | unsigned int max_reqs = nr_events; | |
744 | ||
e1bdd5f2 KO |
745 | /* |
746 | * We keep track of the number of available ringbuffer slots, to prevent | |
747 | * overflow (reqs_available), and we also use percpu counters for this. | |
748 | * | |
749 | * So since up to half the slots might be on other cpu's percpu counters | |
750 | * and unavailable, double nr_events so userspace sees what they | |
751 | * expected: additionally, we move req_batch slots to/from percpu | |
752 | * counters at a time, so make sure that isn't 0: | |
753 | */ | |
754 | nr_events = max(nr_events, num_possible_cpus() * 4); | |
755 | nr_events *= 2; | |
756 | ||
1da177e4 | 757 | /* Prevent overflows */ |
08397acd | 758 | if (nr_events > (0x10000000U / sizeof(struct io_event))) { |
1da177e4 LT |
759 | pr_debug("ENOMEM: nr_events too high\n"); |
760 | return ERR_PTR(-EINVAL); | |
761 | } | |
762 | ||
2a8a9867 | 763 | if (!nr_events || (unsigned long)max_reqs > aio_max_nr) |
1da177e4 LT |
764 | return ERR_PTR(-EAGAIN); |
765 | ||
c3762229 | 766 | ctx = kmem_cache_zalloc(kioctx_cachep, GFP_KERNEL); |
1da177e4 LT |
767 | if (!ctx) |
768 | return ERR_PTR(-ENOMEM); | |
769 | ||
2a8a9867 | 770 | ctx->max_reqs = max_reqs; |
1da177e4 | 771 | |
1da177e4 | 772 | spin_lock_init(&ctx->ctx_lock); |
0460fef2 | 773 | spin_lock_init(&ctx->completion_lock); |
58c85dc2 | 774 | mutex_init(&ctx->ring_lock); |
fa8a53c3 BL |
775 | /* Protect against page migration throughout kiotx setup by keeping |
776 | * the ring_lock mutex held until setup is complete. */ | |
777 | mutex_lock(&ctx->ring_lock); | |
1da177e4 LT |
778 | init_waitqueue_head(&ctx->wait); |
779 | ||
780 | INIT_LIST_HEAD(&ctx->active_reqs); | |
1da177e4 | 781 | |
2aad2a86 | 782 | if (percpu_ref_init(&ctx->users, free_ioctx_users, 0, GFP_KERNEL)) |
fa8a53c3 BL |
783 | goto err; |
784 | ||
2aad2a86 | 785 | if (percpu_ref_init(&ctx->reqs, free_ioctx_reqs, 0, GFP_KERNEL)) |
fa8a53c3 BL |
786 | goto err; |
787 | ||
e1bdd5f2 KO |
788 | ctx->cpu = alloc_percpu(struct kioctx_cpu); |
789 | if (!ctx->cpu) | |
e34ecee2 | 790 | goto err; |
1da177e4 | 791 | |
2a8a9867 | 792 | err = aio_setup_ring(ctx, nr_events); |
fa8a53c3 | 793 | if (err < 0) |
e34ecee2 | 794 | goto err; |
e1bdd5f2 | 795 | |
34e83fc6 | 796 | atomic_set(&ctx->reqs_available, ctx->nr_events - 1); |
e1bdd5f2 | 797 | ctx->req_batch = (ctx->nr_events - 1) / (num_possible_cpus() * 4); |
6878ea72 BL |
798 | if (ctx->req_batch < 1) |
799 | ctx->req_batch = 1; | |
34e83fc6 | 800 | |
1da177e4 | 801 | /* limit the number of system wide aios */ |
9fa1cb39 | 802 | spin_lock(&aio_nr_lock); |
2a8a9867 MFO |
803 | if (aio_nr + ctx->max_reqs > aio_max_nr || |
804 | aio_nr + ctx->max_reqs < aio_nr) { | |
9fa1cb39 | 805 | spin_unlock(&aio_nr_lock); |
e34ecee2 | 806 | err = -EAGAIN; |
d1b94327 | 807 | goto err_ctx; |
2dd542b7 AV |
808 | } |
809 | aio_nr += ctx->max_reqs; | |
9fa1cb39 | 810 | spin_unlock(&aio_nr_lock); |
1da177e4 | 811 | |
1881686f BL |
812 | percpu_ref_get(&ctx->users); /* io_setup() will drop this ref */ |
813 | percpu_ref_get(&ctx->reqs); /* free_ioctx_users() will drop this */ | |
723be6e3 | 814 | |
da90382c BL |
815 | err = ioctx_add_table(ctx, mm); |
816 | if (err) | |
e34ecee2 | 817 | goto err_cleanup; |
da90382c | 818 | |
fa8a53c3 BL |
819 | /* Release the ring_lock mutex now that all setup is complete. */ |
820 | mutex_unlock(&ctx->ring_lock); | |
821 | ||
caf4167a | 822 | pr_debug("allocated ioctx %p[%ld]: mm=%p mask=0x%x\n", |
58c85dc2 | 823 | ctx, ctx->user_id, mm, ctx->nr_events); |
1da177e4 LT |
824 | return ctx; |
825 | ||
e34ecee2 KO |
826 | err_cleanup: |
827 | aio_nr_sub(ctx->max_reqs); | |
d1b94327 | 828 | err_ctx: |
deeb8525 AV |
829 | atomic_set(&ctx->dead, 1); |
830 | if (ctx->mmap_size) | |
831 | vm_munmap(ctx->mmap_base, ctx->mmap_size); | |
d1b94327 | 832 | aio_free_ring(ctx); |
e34ecee2 | 833 | err: |
fa8a53c3 | 834 | mutex_unlock(&ctx->ring_lock); |
e1bdd5f2 | 835 | free_percpu(ctx->cpu); |
9a1049da TH |
836 | percpu_ref_exit(&ctx->reqs); |
837 | percpu_ref_exit(&ctx->users); | |
1da177e4 | 838 | kmem_cache_free(kioctx_cachep, ctx); |
caf4167a | 839 | pr_debug("error allocating ioctx %d\n", err); |
e23754f8 | 840 | return ERR_PTR(err); |
1da177e4 LT |
841 | } |
842 | ||
36f55889 KO |
843 | /* kill_ioctx |
844 | * Cancels all outstanding aio requests on an aio context. Used | |
845 | * when the processes owning a context have all exited to encourage | |
846 | * the rapid destruction of the kioctx. | |
847 | */ | |
fb2d4483 | 848 | static int kill_ioctx(struct mm_struct *mm, struct kioctx *ctx, |
dc48e56d | 849 | struct ctx_rq_wait *wait) |
36f55889 | 850 | { |
fa88b6f8 | 851 | struct kioctx_table *table; |
db446a08 | 852 | |
b2edffdd AV |
853 | spin_lock(&mm->ioctx_lock); |
854 | if (atomic_xchg(&ctx->dead, 1)) { | |
855 | spin_unlock(&mm->ioctx_lock); | |
fa88b6f8 | 856 | return -EINVAL; |
b2edffdd | 857 | } |
db446a08 | 858 | |
855ef0de | 859 | table = rcu_dereference_raw(mm->ioctx_table); |
d0264c01 TH |
860 | WARN_ON(ctx != rcu_access_pointer(table->table[ctx->id])); |
861 | RCU_INIT_POINTER(table->table[ctx->id], NULL); | |
fa88b6f8 | 862 | spin_unlock(&mm->ioctx_lock); |
4fcc712f | 863 | |
a6d7cff4 | 864 | /* free_ioctx_reqs() will do the necessary RCU synchronization */ |
fa88b6f8 | 865 | wake_up_all(&ctx->wait); |
4fcc712f | 866 | |
fa88b6f8 BL |
867 | /* |
868 | * It'd be more correct to do this in free_ioctx(), after all | |
869 | * the outstanding kiocbs have finished - but by then io_destroy | |
870 | * has already returned, so io_setup() could potentially return | |
871 | * -EAGAIN with no ioctxs actually in use (as far as userspace | |
872 | * could tell). | |
873 | */ | |
874 | aio_nr_sub(ctx->max_reqs); | |
4fcc712f | 875 | |
fa88b6f8 BL |
876 | if (ctx->mmap_size) |
877 | vm_munmap(ctx->mmap_base, ctx->mmap_size); | |
fb2d4483 | 878 | |
dc48e56d | 879 | ctx->rq_wait = wait; |
fa88b6f8 BL |
880 | percpu_ref_kill(&ctx->users); |
881 | return 0; | |
1da177e4 LT |
882 | } |
883 | ||
36f55889 KO |
884 | /* |
885 | * exit_aio: called when the last user of mm goes away. At this point, there is | |
886 | * no way for any new requests to be submited or any of the io_* syscalls to be | |
887 | * called on the context. | |
888 | * | |
889 | * There may be outstanding kiocbs, but free_ioctx() will explicitly wait on | |
890 | * them. | |
1da177e4 | 891 | */ |
fc9b52cd | 892 | void exit_aio(struct mm_struct *mm) |
1da177e4 | 893 | { |
4b70ac5f | 894 | struct kioctx_table *table = rcu_dereference_raw(mm->ioctx_table); |
dc48e56d JA |
895 | struct ctx_rq_wait wait; |
896 | int i, skipped; | |
db446a08 | 897 | |
4b70ac5f ON |
898 | if (!table) |
899 | return; | |
db446a08 | 900 | |
dc48e56d JA |
901 | atomic_set(&wait.count, table->nr); |
902 | init_completion(&wait.comp); | |
903 | ||
904 | skipped = 0; | |
4b70ac5f | 905 | for (i = 0; i < table->nr; ++i) { |
d0264c01 TH |
906 | struct kioctx *ctx = |
907 | rcu_dereference_protected(table->table[i], true); | |
abf137dd | 908 | |
dc48e56d JA |
909 | if (!ctx) { |
910 | skipped++; | |
4b70ac5f | 911 | continue; |
dc48e56d JA |
912 | } |
913 | ||
936af157 | 914 | /* |
4b70ac5f ON |
915 | * We don't need to bother with munmap() here - exit_mmap(mm) |
916 | * is coming and it'll unmap everything. And we simply can't, | |
917 | * this is not necessarily our ->mm. | |
918 | * Since kill_ioctx() uses non-zero ->mmap_size as indicator | |
919 | * that it needs to unmap the area, just set it to 0. | |
936af157 | 920 | */ |
58c85dc2 | 921 | ctx->mmap_size = 0; |
dc48e56d JA |
922 | kill_ioctx(mm, ctx, &wait); |
923 | } | |
36f55889 | 924 | |
dc48e56d | 925 | if (!atomic_sub_and_test(skipped, &wait.count)) { |
6098b45b | 926 | /* Wait until all IO for the context are done. */ |
dc48e56d | 927 | wait_for_completion(&wait.comp); |
1da177e4 | 928 | } |
4b70ac5f ON |
929 | |
930 | RCU_INIT_POINTER(mm->ioctx_table, NULL); | |
931 | kfree(table); | |
1da177e4 LT |
932 | } |
933 | ||
e1bdd5f2 KO |
934 | static void put_reqs_available(struct kioctx *ctx, unsigned nr) |
935 | { | |
936 | struct kioctx_cpu *kcpu; | |
263782c1 | 937 | unsigned long flags; |
e1bdd5f2 | 938 | |
263782c1 | 939 | local_irq_save(flags); |
be6fb451 | 940 | kcpu = this_cpu_ptr(ctx->cpu); |
e1bdd5f2 | 941 | kcpu->reqs_available += nr; |
263782c1 | 942 | |
e1bdd5f2 KO |
943 | while (kcpu->reqs_available >= ctx->req_batch * 2) { |
944 | kcpu->reqs_available -= ctx->req_batch; | |
945 | atomic_add(ctx->req_batch, &ctx->reqs_available); | |
946 | } | |
947 | ||
263782c1 | 948 | local_irq_restore(flags); |
e1bdd5f2 KO |
949 | } |
950 | ||
432c7997 | 951 | static bool __get_reqs_available(struct kioctx *ctx) |
e1bdd5f2 KO |
952 | { |
953 | struct kioctx_cpu *kcpu; | |
954 | bool ret = false; | |
263782c1 | 955 | unsigned long flags; |
e1bdd5f2 | 956 | |
263782c1 | 957 | local_irq_save(flags); |
be6fb451 | 958 | kcpu = this_cpu_ptr(ctx->cpu); |
e1bdd5f2 | 959 | if (!kcpu->reqs_available) { |
38ace0d5 | 960 | int avail = atomic_read(&ctx->reqs_available); |
e1bdd5f2 KO |
961 | |
962 | do { | |
963 | if (avail < ctx->req_batch) | |
964 | goto out; | |
38ace0d5 UB |
965 | } while (!atomic_try_cmpxchg(&ctx->reqs_available, |
966 | &avail, avail - ctx->req_batch)); | |
e1bdd5f2 KO |
967 | |
968 | kcpu->reqs_available += ctx->req_batch; | |
969 | } | |
970 | ||
971 | ret = true; | |
972 | kcpu->reqs_available--; | |
973 | out: | |
263782c1 | 974 | local_irq_restore(flags); |
e1bdd5f2 KO |
975 | return ret; |
976 | } | |
977 | ||
d856f32a BL |
978 | /* refill_reqs_available |
979 | * Updates the reqs_available reference counts used for tracking the | |
980 | * number of free slots in the completion ring. This can be called | |
981 | * from aio_complete() (to optimistically update reqs_available) or | |
982 | * from aio_get_req() (the we're out of events case). It must be | |
983 | * called holding ctx->completion_lock. | |
984 | */ | |
985 | static void refill_reqs_available(struct kioctx *ctx, unsigned head, | |
986 | unsigned tail) | |
987 | { | |
988 | unsigned events_in_ring, completed; | |
989 | ||
990 | /* Clamp head since userland can write to it. */ | |
991 | head %= ctx->nr_events; | |
992 | if (head <= tail) | |
993 | events_in_ring = tail - head; | |
994 | else | |
995 | events_in_ring = ctx->nr_events - (head - tail); | |
996 | ||
997 | completed = ctx->completed_events; | |
998 | if (events_in_ring < completed) | |
999 | completed -= events_in_ring; | |
1000 | else | |
1001 | completed = 0; | |
1002 | ||
1003 | if (!completed) | |
1004 | return; | |
1005 | ||
1006 | ctx->completed_events -= completed; | |
1007 | put_reqs_available(ctx, completed); | |
1008 | } | |
1009 | ||
1010 | /* user_refill_reqs_available | |
1011 | * Called to refill reqs_available when aio_get_req() encounters an | |
1012 | * out of space in the completion ring. | |
1013 | */ | |
1014 | static void user_refill_reqs_available(struct kioctx *ctx) | |
1015 | { | |
1016 | spin_lock_irq(&ctx->completion_lock); | |
1017 | if (ctx->completed_events) { | |
1018 | struct aio_ring *ring; | |
1019 | unsigned head; | |
1020 | ||
1021 | /* Access of ring->head may race with aio_read_events_ring() | |
1022 | * here, but that's okay since whether we read the old version | |
1023 | * or the new version, and either will be valid. The important | |
1024 | * part is that head cannot pass tail since we prevent | |
1025 | * aio_complete() from updating tail by holding | |
1026 | * ctx->completion_lock. Even if head is invalid, the check | |
1027 | * against ctx->completed_events below will make sure we do the | |
1028 | * safe/right thing. | |
1029 | */ | |
16594e60 | 1030 | ring = folio_address(ctx->ring_folios[0]); |
d856f32a | 1031 | head = ring->head; |
d856f32a BL |
1032 | |
1033 | refill_reqs_available(ctx, head, ctx->tail); | |
1034 | } | |
1035 | ||
1036 | spin_unlock_irq(&ctx->completion_lock); | |
1037 | } | |
1038 | ||
432c7997 CH |
1039 | static bool get_reqs_available(struct kioctx *ctx) |
1040 | { | |
1041 | if (__get_reqs_available(ctx)) | |
1042 | return true; | |
1043 | user_refill_reqs_available(ctx); | |
1044 | return __get_reqs_available(ctx); | |
1045 | } | |
1046 | ||
1da177e4 | 1047 | /* aio_get_req |
57282d8f KO |
1048 | * Allocate a slot for an aio request. |
1049 | * Returns NULL if no requests are free. | |
b53119f1 LT |
1050 | * |
1051 | * The refcount is initialized to 2 - one for the async op completion, | |
1052 | * one for the synchronous code that does this. | |
1da177e4 | 1053 | */ |
04b2fa9f | 1054 | static inline struct aio_kiocb *aio_get_req(struct kioctx *ctx) |
1da177e4 | 1055 | { |
04b2fa9f | 1056 | struct aio_kiocb *req; |
a1c8eae7 | 1057 | |
2bc4ca9b | 1058 | req = kmem_cache_alloc(kiocb_cachep, GFP_KERNEL); |
1da177e4 | 1059 | if (unlikely(!req)) |
432c7997 | 1060 | return NULL; |
1da177e4 | 1061 | |
fa0ca2ae | 1062 | if (unlikely(!get_reqs_available(ctx))) { |
6af1c849 | 1063 | kmem_cache_free(kiocb_cachep, req); |
fa0ca2ae AV |
1064 | return NULL; |
1065 | } | |
1066 | ||
e34ecee2 | 1067 | percpu_ref_get(&ctx->reqs); |
2bc4ca9b | 1068 | req->ki_ctx = ctx; |
75321b50 | 1069 | INIT_LIST_HEAD(&req->ki_list); |
b53119f1 | 1070 | refcount_set(&req->ki_refcnt, 2); |
2bc4ca9b | 1071 | req->ki_eventfd = NULL; |
080d676d | 1072 | return req; |
1da177e4 LT |
1073 | } |
1074 | ||
d5470b59 | 1075 | static struct kioctx *lookup_ioctx(unsigned long ctx_id) |
1da177e4 | 1076 | { |
db446a08 | 1077 | struct aio_ring __user *ring = (void __user *)ctx_id; |
abf137dd | 1078 | struct mm_struct *mm = current->mm; |
65c24491 | 1079 | struct kioctx *ctx, *ret = NULL; |
db446a08 BL |
1080 | struct kioctx_table *table; |
1081 | unsigned id; | |
1082 | ||
1083 | if (get_user(id, &ring->id)) | |
1084 | return NULL; | |
1da177e4 | 1085 | |
abf137dd | 1086 | rcu_read_lock(); |
db446a08 | 1087 | table = rcu_dereference(mm->ioctx_table); |
abf137dd | 1088 | |
db446a08 BL |
1089 | if (!table || id >= table->nr) |
1090 | goto out; | |
1da177e4 | 1091 | |
a538e3ff | 1092 | id = array_index_nospec(id, table->nr); |
d0264c01 | 1093 | ctx = rcu_dereference(table->table[id]); |
f30d704f | 1094 | if (ctx && ctx->user_id == ctx_id) { |
baf10564 AV |
1095 | if (percpu_ref_tryget_live(&ctx->users)) |
1096 | ret = ctx; | |
db446a08 BL |
1097 | } |
1098 | out: | |
abf137dd | 1099 | rcu_read_unlock(); |
65c24491 | 1100 | return ret; |
1da177e4 LT |
1101 | } |
1102 | ||
b53119f1 LT |
1103 | static inline void iocb_destroy(struct aio_kiocb *iocb) |
1104 | { | |
74259703 AV |
1105 | if (iocb->ki_eventfd) |
1106 | eventfd_ctx_put(iocb->ki_eventfd); | |
b53119f1 LT |
1107 | if (iocb->ki_filp) |
1108 | fput(iocb->ki_filp); | |
1109 | percpu_ref_put(&iocb->ki_ctx->reqs); | |
1110 | kmem_cache_free(kiocb_cachep, iocb); | |
1111 | } | |
1112 | ||
71eb6b6b KO |
1113 | struct aio_waiter { |
1114 | struct wait_queue_entry w; | |
1115 | size_t min_nr; | |
1116 | }; | |
1117 | ||
1da177e4 LT |
1118 | /* aio_complete |
1119 | * Called when the io request on the given iocb is complete. | |
1da177e4 | 1120 | */ |
2bb874c0 | 1121 | static void aio_complete(struct aio_kiocb *iocb) |
1da177e4 LT |
1122 | { |
1123 | struct kioctx *ctx = iocb->ki_ctx; | |
1da177e4 | 1124 | struct aio_ring *ring; |
21b40200 | 1125 | struct io_event *ev_page, *event; |
71eb6b6b | 1126 | unsigned tail, pos, head, avail; |
1da177e4 | 1127 | unsigned long flags; |
1da177e4 | 1128 | |
0460fef2 KO |
1129 | /* |
1130 | * Add a completion event to the ring buffer. Must be done holding | |
4b30f07e | 1131 | * ctx->completion_lock to prevent other code from messing with the tail |
0460fef2 KO |
1132 | * pointer since we might be called from irq context. |
1133 | */ | |
1134 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
1135 | ||
58c85dc2 | 1136 | tail = ctx->tail; |
21b40200 KO |
1137 | pos = tail + AIO_EVENTS_OFFSET; |
1138 | ||
58c85dc2 | 1139 | if (++tail >= ctx->nr_events) |
4bf69b2a | 1140 | tail = 0; |
1da177e4 | 1141 | |
16594e60 | 1142 | ev_page = folio_address(ctx->ring_folios[pos / AIO_EVENTS_PER_PAGE]); |
21b40200 KO |
1143 | event = ev_page + pos % AIO_EVENTS_PER_PAGE; |
1144 | ||
a9339b78 | 1145 | *event = iocb->ki_res; |
1da177e4 | 1146 | |
16594e60 | 1147 | flush_dcache_folio(ctx->ring_folios[pos / AIO_EVENTS_PER_PAGE]); |
21b40200 | 1148 | |
a9339b78 AV |
1149 | pr_debug("%p[%u]: %p: %p %Lx %Lx %Lx\n", ctx, tail, iocb, |
1150 | (void __user *)(unsigned long)iocb->ki_res.obj, | |
1151 | iocb->ki_res.data, iocb->ki_res.res, iocb->ki_res.res2); | |
1da177e4 LT |
1152 | |
1153 | /* after flagging the request as done, we | |
1154 | * must never even look at it again | |
1155 | */ | |
1156 | smp_wmb(); /* make event visible before updating tail */ | |
1157 | ||
58c85dc2 | 1158 | ctx->tail = tail; |
1da177e4 | 1159 | |
16594e60 | 1160 | ring = folio_address(ctx->ring_folios[0]); |
d856f32a | 1161 | head = ring->head; |
21b40200 | 1162 | ring->tail = tail; |
16594e60 | 1163 | flush_dcache_folio(ctx->ring_folios[0]); |
1da177e4 | 1164 | |
d856f32a BL |
1165 | ctx->completed_events++; |
1166 | if (ctx->completed_events > 1) | |
1167 | refill_reqs_available(ctx, head, tail); | |
71eb6b6b KO |
1168 | |
1169 | avail = tail > head | |
1170 | ? tail - head | |
1171 | : tail + ctx->nr_events - head; | |
0460fef2 KO |
1172 | spin_unlock_irqrestore(&ctx->completion_lock, flags); |
1173 | ||
21b40200 | 1174 | pr_debug("added to ring %p at [%u]\n", iocb, tail); |
8d1c98b0 DL |
1175 | |
1176 | /* | |
1177 | * Check if the user asked us to deliver the result through an | |
1178 | * eventfd. The eventfd_signal() function is safe to be called | |
1179 | * from IRQ context. | |
1180 | */ | |
74259703 | 1181 | if (iocb->ki_eventfd) |
3652117f | 1182 | eventfd_signal(iocb->ki_eventfd); |
8d1c98b0 | 1183 | |
6cb2a210 QB |
1184 | /* |
1185 | * We have to order our ring_info tail store above and test | |
1186 | * of the wait list below outside the wait lock. This is | |
1187 | * like in wake_up_bit() where clearing a bit has to be | |
1188 | * ordered with the unlocked test. | |
1189 | */ | |
1190 | smp_mb(); | |
1191 | ||
71eb6b6b KO |
1192 | if (waitqueue_active(&ctx->wait)) { |
1193 | struct aio_waiter *curr, *next; | |
1194 | unsigned long flags; | |
1195 | ||
1196 | spin_lock_irqsave(&ctx->wait.lock, flags); | |
1197 | list_for_each_entry_safe(curr, next, &ctx->wait.head, w.entry) | |
1198 | if (avail >= curr->min_nr) { | |
71eb6b6b | 1199 | wake_up_process(curr->w.private); |
caeb4b0a | 1200 | list_del_init_careful(&curr->w.entry); |
71eb6b6b KO |
1201 | } |
1202 | spin_unlock_irqrestore(&ctx->wait.lock, flags); | |
1203 | } | |
2bb874c0 AV |
1204 | } |
1205 | ||
1206 | static inline void iocb_put(struct aio_kiocb *iocb) | |
1207 | { | |
1208 | if (refcount_dec_and_test(&iocb->ki_refcnt)) { | |
1209 | aio_complete(iocb); | |
1210 | iocb_destroy(iocb); | |
1211 | } | |
1da177e4 LT |
1212 | } |
1213 | ||
2be4e7de | 1214 | /* aio_read_events_ring |
a31ad380 KO |
1215 | * Pull an event off of the ioctx's event ring. Returns the number of |
1216 | * events fetched | |
1da177e4 | 1217 | */ |
a31ad380 KO |
1218 | static long aio_read_events_ring(struct kioctx *ctx, |
1219 | struct io_event __user *event, long nr) | |
1da177e4 | 1220 | { |
1da177e4 | 1221 | struct aio_ring *ring; |
5ffac122 | 1222 | unsigned head, tail, pos; |
a31ad380 KO |
1223 | long ret = 0; |
1224 | int copy_ret; | |
1225 | ||
9c9ce763 DC |
1226 | /* |
1227 | * The mutex can block and wake us up and that will cause | |
1228 | * wait_event_interruptible_hrtimeout() to schedule without sleeping | |
1229 | * and repeat. This should be rare enough that it doesn't cause | |
1230 | * peformance issues. See the comment in read_events() for more detail. | |
1231 | */ | |
1232 | sched_annotate_sleep(); | |
58c85dc2 | 1233 | mutex_lock(&ctx->ring_lock); |
1da177e4 | 1234 | |
16594e60 KW |
1235 | /* Access to ->ring_folios here is protected by ctx->ring_lock. */ |
1236 | ring = folio_address(ctx->ring_folios[0]); | |
a31ad380 | 1237 | head = ring->head; |
5ffac122 | 1238 | tail = ring->tail; |
a31ad380 | 1239 | |
2ff396be JM |
1240 | /* |
1241 | * Ensure that once we've read the current tail pointer, that | |
1242 | * we also see the events that were stored up to the tail. | |
1243 | */ | |
1244 | smp_rmb(); | |
1245 | ||
5ffac122 | 1246 | pr_debug("h%u t%u m%u\n", head, tail, ctx->nr_events); |
1da177e4 | 1247 | |
5ffac122 | 1248 | if (head == tail) |
1da177e4 LT |
1249 | goto out; |
1250 | ||
edfbbf38 BL |
1251 | head %= ctx->nr_events; |
1252 | tail %= ctx->nr_events; | |
1253 | ||
a31ad380 KO |
1254 | while (ret < nr) { |
1255 | long avail; | |
1256 | struct io_event *ev; | |
16594e60 | 1257 | struct folio *folio; |
a31ad380 | 1258 | |
5ffac122 KO |
1259 | avail = (head <= tail ? tail : ctx->nr_events) - head; |
1260 | if (head == tail) | |
a31ad380 KO |
1261 | break; |
1262 | ||
a31ad380 | 1263 | pos = head + AIO_EVENTS_OFFSET; |
16594e60 | 1264 | folio = ctx->ring_folios[pos / AIO_EVENTS_PER_PAGE]; |
a31ad380 KO |
1265 | pos %= AIO_EVENTS_PER_PAGE; |
1266 | ||
d2988bd4 AV |
1267 | avail = min(avail, nr - ret); |
1268 | avail = min_t(long, avail, AIO_EVENTS_PER_PAGE - pos); | |
1269 | ||
16594e60 | 1270 | ev = folio_address(folio); |
a31ad380 KO |
1271 | copy_ret = copy_to_user(event + ret, ev + pos, |
1272 | sizeof(*ev) * avail); | |
a31ad380 KO |
1273 | |
1274 | if (unlikely(copy_ret)) { | |
1275 | ret = -EFAULT; | |
1276 | goto out; | |
1277 | } | |
1278 | ||
1279 | ret += avail; | |
1280 | head += avail; | |
58c85dc2 | 1281 | head %= ctx->nr_events; |
1da177e4 | 1282 | } |
1da177e4 | 1283 | |
16594e60 | 1284 | ring = folio_address(ctx->ring_folios[0]); |
a31ad380 | 1285 | ring->head = head; |
16594e60 | 1286 | flush_dcache_folio(ctx->ring_folios[0]); |
a31ad380 | 1287 | |
5ffac122 | 1288 | pr_debug("%li h%u t%u\n", ret, head, tail); |
a31ad380 | 1289 | out: |
58c85dc2 | 1290 | mutex_unlock(&ctx->ring_lock); |
a31ad380 | 1291 | |
1da177e4 LT |
1292 | return ret; |
1293 | } | |
1294 | ||
a31ad380 KO |
1295 | static bool aio_read_events(struct kioctx *ctx, long min_nr, long nr, |
1296 | struct io_event __user *event, long *i) | |
1da177e4 | 1297 | { |
a31ad380 | 1298 | long ret = aio_read_events_ring(ctx, event + *i, nr - *i); |
1da177e4 | 1299 | |
a31ad380 KO |
1300 | if (ret > 0) |
1301 | *i += ret; | |
1da177e4 | 1302 | |
a31ad380 KO |
1303 | if (unlikely(atomic_read(&ctx->dead))) |
1304 | ret = -EINVAL; | |
1da177e4 | 1305 | |
a31ad380 KO |
1306 | if (!*i) |
1307 | *i = ret; | |
1da177e4 | 1308 | |
a31ad380 | 1309 | return ret < 0 || *i >= min_nr; |
1da177e4 LT |
1310 | } |
1311 | ||
a31ad380 | 1312 | static long read_events(struct kioctx *ctx, long min_nr, long nr, |
1da177e4 | 1313 | struct io_event __user *event, |
fa2e62a5 | 1314 | ktime_t until) |
1da177e4 | 1315 | { |
71eb6b6b KO |
1316 | struct hrtimer_sleeper t; |
1317 | struct aio_waiter w; | |
1318 | long ret = 0, ret2 = 0; | |
1da177e4 | 1319 | |
a31ad380 KO |
1320 | /* |
1321 | * Note that aio_read_events() is being called as the conditional - i.e. | |
1322 | * we're calling it after prepare_to_wait() has set task state to | |
1323 | * TASK_INTERRUPTIBLE. | |
1324 | * | |
1325 | * But aio_read_events() can block, and if it blocks it's going to flip | |
1326 | * the task state back to TASK_RUNNING. | |
1327 | * | |
1328 | * This should be ok, provided it doesn't flip the state back to | |
1329 | * TASK_RUNNING and return 0 too much - that causes us to spin. That | |
1330 | * will only happen if the mutex_lock() call blocks, and we then find | |
1331 | * the ringbuffer empty. So in practice we should be ok, but it's | |
1332 | * something to be aware of when touching this code. | |
1333 | */ | |
71eb6b6b KO |
1334 | aio_read_events(ctx, min_nr, nr, event, &ret); |
1335 | if (until == 0 || ret < 0 || ret >= min_nr) | |
1336 | return ret; | |
1337 | ||
28e70352 | 1338 | hrtimer_setup_sleeper_on_stack(&t, CLOCK_MONOTONIC, HRTIMER_MODE_REL); |
71eb6b6b KO |
1339 | if (until != KTIME_MAX) { |
1340 | hrtimer_set_expires_range_ns(&t.timer, until, current->timer_slack_ns); | |
1341 | hrtimer_sleeper_start_expires(&t, HRTIMER_MODE_REL); | |
1342 | } | |
1343 | ||
1344 | init_wait(&w.w); | |
1345 | ||
1346 | while (1) { | |
1347 | unsigned long nr_got = ret; | |
1348 | ||
1349 | w.min_nr = min_nr - ret; | |
1350 | ||
1351 | ret2 = prepare_to_wait_event(&ctx->wait, &w.w, TASK_INTERRUPTIBLE); | |
1352 | if (!ret2 && !t.task) | |
1353 | ret2 = -ETIME; | |
1354 | ||
1355 | if (aio_read_events(ctx, min_nr, nr, event, &ret) || ret2) | |
1356 | break; | |
1357 | ||
1358 | if (nr_got == ret) | |
1359 | schedule(); | |
1360 | } | |
1361 | ||
1362 | finish_wait(&ctx->wait, &w.w); | |
1363 | hrtimer_cancel(&t.timer); | |
1364 | destroy_hrtimer_on_stack(&t.timer); | |
1365 | ||
a31ad380 | 1366 | return ret; |
1da177e4 LT |
1367 | } |
1368 | ||
1da177e4 LT |
1369 | /* sys_io_setup: |
1370 | * Create an aio_context capable of receiving at least nr_events. | |
1371 | * ctxp must not point to an aio_context that already exists, and | |
1372 | * must be initialized to 0 prior to the call. On successful | |
1373 | * creation of the aio_context, *ctxp is filled in with the resulting | |
1374 | * handle. May fail with -EINVAL if *ctxp is not initialized, | |
1375 | * if the specified nr_events exceeds internal limits. May fail | |
1376 | * with -EAGAIN if the specified nr_events exceeds the user's limit | |
1377 | * of available events. May fail with -ENOMEM if insufficient kernel | |
1378 | * resources are available. May fail with -EFAULT if an invalid | |
1379 | * pointer is passed for ctxp. Will fail with -ENOSYS if not | |
1380 | * implemented. | |
1381 | */ | |
002c8976 | 1382 | SYSCALL_DEFINE2(io_setup, unsigned, nr_events, aio_context_t __user *, ctxp) |
1da177e4 LT |
1383 | { |
1384 | struct kioctx *ioctx = NULL; | |
1385 | unsigned long ctx; | |
1386 | long ret; | |
1387 | ||
1388 | ret = get_user(ctx, ctxp); | |
1389 | if (unlikely(ret)) | |
1390 | goto out; | |
1391 | ||
1392 | ret = -EINVAL; | |
d55b5fda | 1393 | if (unlikely(ctx || nr_events == 0)) { |
acd88d4e | 1394 | pr_debug("EINVAL: ctx %lu nr_events %u\n", |
d55b5fda | 1395 | ctx, nr_events); |
1da177e4 LT |
1396 | goto out; |
1397 | } | |
1398 | ||
1399 | ioctx = ioctx_alloc(nr_events); | |
1400 | ret = PTR_ERR(ioctx); | |
1401 | if (!IS_ERR(ioctx)) { | |
1402 | ret = put_user(ioctx->user_id, ctxp); | |
a2e1859a | 1403 | if (ret) |
e02ba72a | 1404 | kill_ioctx(current->mm, ioctx, NULL); |
723be6e3 | 1405 | percpu_ref_put(&ioctx->users); |
1da177e4 LT |
1406 | } |
1407 | ||
1408 | out: | |
1409 | return ret; | |
1410 | } | |
1411 | ||
c00d2c7e AV |
1412 | #ifdef CONFIG_COMPAT |
1413 | COMPAT_SYSCALL_DEFINE2(io_setup, unsigned, nr_events, u32 __user *, ctx32p) | |
1414 | { | |
1415 | struct kioctx *ioctx = NULL; | |
1416 | unsigned long ctx; | |
1417 | long ret; | |
1418 | ||
1419 | ret = get_user(ctx, ctx32p); | |
1420 | if (unlikely(ret)) | |
1421 | goto out; | |
1422 | ||
1423 | ret = -EINVAL; | |
1424 | if (unlikely(ctx || nr_events == 0)) { | |
1425 | pr_debug("EINVAL: ctx %lu nr_events %u\n", | |
1426 | ctx, nr_events); | |
1427 | goto out; | |
1428 | } | |
1429 | ||
1430 | ioctx = ioctx_alloc(nr_events); | |
1431 | ret = PTR_ERR(ioctx); | |
1432 | if (!IS_ERR(ioctx)) { | |
1433 | /* truncating is ok because it's a user address */ | |
1434 | ret = put_user((u32)ioctx->user_id, ctx32p); | |
1435 | if (ret) | |
1436 | kill_ioctx(current->mm, ioctx, NULL); | |
1437 | percpu_ref_put(&ioctx->users); | |
1438 | } | |
1439 | ||
1440 | out: | |
1441 | return ret; | |
1442 | } | |
1443 | #endif | |
1444 | ||
1da177e4 LT |
1445 | /* sys_io_destroy: |
1446 | * Destroy the aio_context specified. May cancel any outstanding | |
1447 | * AIOs and block on completion. Will fail with -ENOSYS if not | |
642b5123 | 1448 | * implemented. May fail with -EINVAL if the context pointed to |
1da177e4 LT |
1449 | * is invalid. |
1450 | */ | |
002c8976 | 1451 | SYSCALL_DEFINE1(io_destroy, aio_context_t, ctx) |
1da177e4 LT |
1452 | { |
1453 | struct kioctx *ioctx = lookup_ioctx(ctx); | |
1454 | if (likely(NULL != ioctx)) { | |
dc48e56d | 1455 | struct ctx_rq_wait wait; |
fb2d4483 | 1456 | int ret; |
e02ba72a | 1457 | |
dc48e56d JA |
1458 | init_completion(&wait.comp); |
1459 | atomic_set(&wait.count, 1); | |
1460 | ||
e02ba72a AP |
1461 | /* Pass requests_done to kill_ioctx() where it can be set |
1462 | * in a thread-safe way. If we try to set it here then we have | |
1463 | * a race condition if two io_destroy() called simultaneously. | |
1464 | */ | |
dc48e56d | 1465 | ret = kill_ioctx(current->mm, ioctx, &wait); |
723be6e3 | 1466 | percpu_ref_put(&ioctx->users); |
e02ba72a AP |
1467 | |
1468 | /* Wait until all IO for the context are done. Otherwise kernel | |
1469 | * keep using user-space buffers even if user thinks the context | |
1470 | * is destroyed. | |
1471 | */ | |
fb2d4483 | 1472 | if (!ret) |
dc48e56d | 1473 | wait_for_completion(&wait.comp); |
e02ba72a | 1474 | |
fb2d4483 | 1475 | return ret; |
1da177e4 | 1476 | } |
acd88d4e | 1477 | pr_debug("EINVAL: invalid context id\n"); |
1da177e4 LT |
1478 | return -EINVAL; |
1479 | } | |
1480 | ||
3c96c7f4 AV |
1481 | static void aio_remove_iocb(struct aio_kiocb *iocb) |
1482 | { | |
1483 | struct kioctx *ctx = iocb->ki_ctx; | |
1484 | unsigned long flags; | |
1485 | ||
1486 | spin_lock_irqsave(&ctx->ctx_lock, flags); | |
1487 | list_del(&iocb->ki_list); | |
1488 | spin_unlock_irqrestore(&ctx->ctx_lock, flags); | |
1489 | } | |
1490 | ||
6b19b766 | 1491 | static void aio_complete_rw(struct kiocb *kiocb, long res) |
54843f87 CH |
1492 | { |
1493 | struct aio_kiocb *iocb = container_of(kiocb, struct aio_kiocb, rw); | |
1494 | ||
3c96c7f4 AV |
1495 | if (!list_empty_careful(&iocb->ki_list)) |
1496 | aio_remove_iocb(iocb); | |
1497 | ||
54843f87 CH |
1498 | if (kiocb->ki_flags & IOCB_WRITE) { |
1499 | struct inode *inode = file_inode(kiocb->ki_filp); | |
1500 | ||
54843f87 | 1501 | if (S_ISREG(inode->i_mode)) |
8c3cfa80 | 1502 | kiocb_end_write(kiocb); |
54843f87 CH |
1503 | } |
1504 | ||
2bb874c0 | 1505 | iocb->ki_res.res = res; |
6b19b766 | 1506 | iocb->ki_res.res2 = 0; |
2bb874c0 | 1507 | iocb_put(iocb); |
54843f87 CH |
1508 | } |
1509 | ||
c34fc6f2 | 1510 | static int aio_prep_rw(struct kiocb *req, const struct iocb *iocb, int rw_type) |
54843f87 CH |
1511 | { |
1512 | int ret; | |
1513 | ||
54843f87 | 1514 | req->ki_complete = aio_complete_rw; |
ec51f8ee | 1515 | req->private = NULL; |
54843f87 | 1516 | req->ki_pos = iocb->aio_offset; |
b820de74 | 1517 | req->ki_flags = req->ki_filp->f_iocb_flags | IOCB_AIO_RW; |
54843f87 CH |
1518 | if (iocb->aio_flags & IOCB_FLAG_RESFD) |
1519 | req->ki_flags |= IOCB_EVENTFD; | |
d9a08a9e AM |
1520 | if (iocb->aio_flags & IOCB_FLAG_IOPRIO) { |
1521 | /* | |
1522 | * If the IOCB_FLAG_IOPRIO flag of aio_flags is set, then | |
1523 | * aio_reqprio is interpreted as an I/O scheduling | |
1524 | * class and priority. | |
1525 | */ | |
1526 | ret = ioprio_check_cap(iocb->aio_reqprio); | |
1527 | if (ret) { | |
9a6d9a62 | 1528 | pr_debug("aio ioprio check cap error: %d\n", ret); |
84c4e1f8 | 1529 | return ret; |
d9a08a9e AM |
1530 | } |
1531 | ||
1532 | req->ki_ioprio = iocb->aio_reqprio; | |
1533 | } else | |
76dc8913 | 1534 | req->ki_ioprio = get_current_ioprio(); |
d9a08a9e | 1535 | |
c34fc6f2 | 1536 | ret = kiocb_set_rw_flags(req, iocb->aio_rw_flags, rw_type); |
54843f87 | 1537 | if (unlikely(ret)) |
84c4e1f8 | 1538 | return ret; |
154989e4 CH |
1539 | |
1540 | req->ki_flags &= ~IOCB_HIPRI; /* no one is going to poll for this I/O */ | |
1541 | return 0; | |
54843f87 CH |
1542 | } |
1543 | ||
87e5e6da JA |
1544 | static ssize_t aio_setup_rw(int rw, const struct iocb *iocb, |
1545 | struct iovec **iovec, bool vectored, bool compat, | |
1546 | struct iov_iter *iter) | |
eed4e51f | 1547 | { |
89319d31 CH |
1548 | void __user *buf = (void __user *)(uintptr_t)iocb->aio_buf; |
1549 | size_t len = iocb->aio_nbytes; | |
1550 | ||
1551 | if (!vectored) { | |
9fd7874c | 1552 | ssize_t ret = import_ubuf(rw, buf, len, iter); |
89319d31 CH |
1553 | *iovec = NULL; |
1554 | return ret; | |
1555 | } | |
89cd35c5 CH |
1556 | |
1557 | return __import_iovec(rw, buf, len, UIO_FASTIOV, iovec, iter, compat); | |
eed4e51f BP |
1558 | } |
1559 | ||
9061d14a | 1560 | static inline void aio_rw_done(struct kiocb *req, ssize_t ret) |
89319d31 CH |
1561 | { |
1562 | switch (ret) { | |
1563 | case -EIOCBQUEUED: | |
9061d14a | 1564 | break; |
89319d31 CH |
1565 | case -ERESTARTSYS: |
1566 | case -ERESTARTNOINTR: | |
1567 | case -ERESTARTNOHAND: | |
1568 | case -ERESTART_RESTARTBLOCK: | |
1569 | /* | |
1570 | * There's no easy way to restart the syscall since other AIO's | |
1571 | * may be already running. Just fail this IO with EINTR. | |
1572 | */ | |
1573 | ret = -EINTR; | |
df561f66 | 1574 | fallthrough; |
89319d31 | 1575 | default: |
6b19b766 | 1576 | req->ki_complete(req, ret); |
89319d31 CH |
1577 | } |
1578 | } | |
1579 | ||
958c13ce | 1580 | static int aio_read(struct kiocb *req, const struct iocb *iocb, |
88a6f18b | 1581 | bool vectored, bool compat) |
1da177e4 | 1582 | { |
00fefb9c | 1583 | struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; |
293bc982 | 1584 | struct iov_iter iter; |
54843f87 | 1585 | struct file *file; |
958c13ce | 1586 | int ret; |
1da177e4 | 1587 | |
c34fc6f2 | 1588 | ret = aio_prep_rw(req, iocb, READ); |
54843f87 CH |
1589 | if (ret) |
1590 | return ret; | |
1591 | file = req->ki_filp; | |
89319d31 | 1592 | if (unlikely(!(file->f_mode & FMODE_READ))) |
84c4e1f8 | 1593 | return -EBADF; |
89319d31 | 1594 | if (unlikely(!file->f_op->read_iter)) |
84c4e1f8 | 1595 | return -EINVAL; |
73a7075e | 1596 | |
de4eda9d | 1597 | ret = aio_setup_rw(ITER_DEST, iocb, &iovec, vectored, compat, &iter); |
87e5e6da | 1598 | if (ret < 0) |
84c4e1f8 | 1599 | return ret; |
89319d31 CH |
1600 | ret = rw_verify_area(READ, file, &req->ki_pos, iov_iter_count(&iter)); |
1601 | if (!ret) | |
7c98f7cb | 1602 | aio_rw_done(req, file->f_op->read_iter(req, &iter)); |
89319d31 CH |
1603 | kfree(iovec); |
1604 | return ret; | |
1605 | } | |
73a7075e | 1606 | |
958c13ce | 1607 | static int aio_write(struct kiocb *req, const struct iocb *iocb, |
88a6f18b | 1608 | bool vectored, bool compat) |
89319d31 | 1609 | { |
89319d31 CH |
1610 | struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; |
1611 | struct iov_iter iter; | |
54843f87 | 1612 | struct file *file; |
958c13ce | 1613 | int ret; |
41ef4eb8 | 1614 | |
c34fc6f2 | 1615 | ret = aio_prep_rw(req, iocb, WRITE); |
54843f87 CH |
1616 | if (ret) |
1617 | return ret; | |
1618 | file = req->ki_filp; | |
1619 | ||
89319d31 | 1620 | if (unlikely(!(file->f_mode & FMODE_WRITE))) |
84c4e1f8 | 1621 | return -EBADF; |
89319d31 | 1622 | if (unlikely(!file->f_op->write_iter)) |
84c4e1f8 | 1623 | return -EINVAL; |
1da177e4 | 1624 | |
de4eda9d | 1625 | ret = aio_setup_rw(ITER_SOURCE, iocb, &iovec, vectored, compat, &iter); |
87e5e6da | 1626 | if (ret < 0) |
84c4e1f8 | 1627 | return ret; |
89319d31 CH |
1628 | ret = rw_verify_area(WRITE, file, &req->ki_pos, iov_iter_count(&iter)); |
1629 | if (!ret) { | |
8c3cfa80 AG |
1630 | if (S_ISREG(file_inode(file)->i_mode)) |
1631 | kiocb_start_write(req); | |
92ce4728 | 1632 | req->ki_flags |= IOCB_WRITE; |
7c98f7cb | 1633 | aio_rw_done(req, file->f_op->write_iter(req, &iter)); |
41ef4eb8 | 1634 | } |
89319d31 CH |
1635 | kfree(iovec); |
1636 | return ret; | |
1da177e4 LT |
1637 | } |
1638 | ||
a3c0d439 CH |
1639 | static void aio_fsync_work(struct work_struct *work) |
1640 | { | |
2bb874c0 | 1641 | struct aio_kiocb *iocb = container_of(work, struct aio_kiocb, fsync.work); |
530f32fc | 1642 | const struct cred *old_cred = override_creds(iocb->fsync.creds); |
a3c0d439 | 1643 | |
2bb874c0 | 1644 | iocb->ki_res.res = vfs_fsync(iocb->fsync.file, iocb->fsync.datasync); |
530f32fc MS |
1645 | revert_creds(old_cred); |
1646 | put_cred(iocb->fsync.creds); | |
2bb874c0 | 1647 | iocb_put(iocb); |
a3c0d439 CH |
1648 | } |
1649 | ||
88a6f18b JA |
1650 | static int aio_fsync(struct fsync_iocb *req, const struct iocb *iocb, |
1651 | bool datasync) | |
a3c0d439 CH |
1652 | { |
1653 | if (unlikely(iocb->aio_buf || iocb->aio_offset || iocb->aio_nbytes || | |
1654 | iocb->aio_rw_flags)) | |
1655 | return -EINVAL; | |
a11e1d43 | 1656 | |
84c4e1f8 | 1657 | if (unlikely(!req->file->f_op->fsync)) |
a3c0d439 | 1658 | return -EINVAL; |
a3c0d439 | 1659 | |
530f32fc MS |
1660 | req->creds = prepare_creds(); |
1661 | if (!req->creds) | |
1662 | return -ENOMEM; | |
1663 | ||
a3c0d439 CH |
1664 | req->datasync = datasync; |
1665 | INIT_WORK(&req->work, aio_fsync_work); | |
1666 | schedule_work(&req->work); | |
9061d14a | 1667 | return 0; |
a3c0d439 CH |
1668 | } |
1669 | ||
01d7a356 JA |
1670 | static void aio_poll_put_work(struct work_struct *work) |
1671 | { | |
1672 | struct poll_iocb *req = container_of(work, struct poll_iocb, work); | |
1673 | struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll); | |
1674 | ||
1675 | iocb_put(iocb); | |
1676 | } | |
1677 | ||
50252e4b EB |
1678 | /* |
1679 | * Safely lock the waitqueue which the request is on, synchronizing with the | |
1680 | * case where the ->poll() provider decides to free its waitqueue early. | |
1681 | * | |
1682 | * Returns true on success, meaning that req->head->lock was locked, req->wait | |
1683 | * is on req->head, and an RCU read lock was taken. Returns false if the | |
1684 | * request was already removed from its waitqueue (which might no longer exist). | |
1685 | */ | |
1686 | static bool poll_iocb_lock_wq(struct poll_iocb *req) | |
1687 | { | |
1688 | wait_queue_head_t *head; | |
1689 | ||
1690 | /* | |
1691 | * While we hold the waitqueue lock and the waitqueue is nonempty, | |
1692 | * wake_up_pollfree() will wait for us. However, taking the waitqueue | |
1693 | * lock in the first place can race with the waitqueue being freed. | |
1694 | * | |
1695 | * We solve this as eventpoll does: by taking advantage of the fact that | |
1696 | * all users of wake_up_pollfree() will RCU-delay the actual free. If | |
1697 | * we enter rcu_read_lock() and see that the pointer to the queue is | |
1698 | * non-NULL, we can then lock it without the memory being freed out from | |
1699 | * under us, then check whether the request is still on the queue. | |
1700 | * | |
1701 | * Keep holding rcu_read_lock() as long as we hold the queue lock, in | |
1702 | * case the caller deletes the entry from the queue, leaving it empty. | |
1703 | * In that case, only RCU prevents the queue memory from being freed. | |
1704 | */ | |
1705 | rcu_read_lock(); | |
1706 | head = smp_load_acquire(&req->head); | |
1707 | if (head) { | |
1708 | spin_lock(&head->lock); | |
1709 | if (!list_empty(&req->wait.entry)) | |
1710 | return true; | |
1711 | spin_unlock(&head->lock); | |
1712 | } | |
1713 | rcu_read_unlock(); | |
1714 | return false; | |
1715 | } | |
1716 | ||
1717 | static void poll_iocb_unlock_wq(struct poll_iocb *req) | |
1718 | { | |
1719 | spin_unlock(&req->head->lock); | |
1720 | rcu_read_unlock(); | |
1721 | } | |
1722 | ||
bfe4037e CH |
1723 | static void aio_poll_complete_work(struct work_struct *work) |
1724 | { | |
1725 | struct poll_iocb *req = container_of(work, struct poll_iocb, work); | |
1726 | struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll); | |
1727 | struct poll_table_struct pt = { ._key = req->events }; | |
1728 | struct kioctx *ctx = iocb->ki_ctx; | |
1729 | __poll_t mask = 0; | |
1730 | ||
1731 | if (!READ_ONCE(req->cancelled)) | |
1732 | mask = vfs_poll(req->file, &pt) & req->events; | |
1733 | ||
1734 | /* | |
1735 | * Note that ->ki_cancel callers also delete iocb from active_reqs after | |
1736 | * calling ->ki_cancel. We need the ctx_lock roundtrip here to | |
1737 | * synchronize with them. In the cancellation case the list_del_init | |
1738 | * itself is not actually needed, but harmless so we keep it in to | |
1739 | * avoid further branches in the fast path. | |
1740 | */ | |
1741 | spin_lock_irq(&ctx->ctx_lock); | |
50252e4b EB |
1742 | if (poll_iocb_lock_wq(req)) { |
1743 | if (!mask && !READ_ONCE(req->cancelled)) { | |
1744 | /* | |
1745 | * The request isn't actually ready to be completed yet. | |
1746 | * Reschedule completion if another wakeup came in. | |
1747 | */ | |
1748 | if (req->work_need_resched) { | |
1749 | schedule_work(&req->work); | |
1750 | req->work_need_resched = false; | |
1751 | } else { | |
1752 | req->work_scheduled = false; | |
1753 | } | |
1754 | poll_iocb_unlock_wq(req); | |
1755 | spin_unlock_irq(&ctx->ctx_lock); | |
1756 | return; | |
363bee27 | 1757 | } |
50252e4b EB |
1758 | list_del_init(&req->wait.entry); |
1759 | poll_iocb_unlock_wq(req); | |
1760 | } /* else, POLLFREE has freed the waitqueue, so we must complete */ | |
bfe4037e | 1761 | list_del_init(&iocb->ki_list); |
af5c72b1 | 1762 | iocb->ki_res.res = mangle_poll(mask); |
bfe4037e CH |
1763 | spin_unlock_irq(&ctx->ctx_lock); |
1764 | ||
af5c72b1 | 1765 | iocb_put(iocb); |
bfe4037e CH |
1766 | } |
1767 | ||
1768 | /* assumes we are called with irqs disabled */ | |
1769 | static int aio_poll_cancel(struct kiocb *iocb) | |
1770 | { | |
1771 | struct aio_kiocb *aiocb = container_of(iocb, struct aio_kiocb, rw); | |
1772 | struct poll_iocb *req = &aiocb->poll; | |
1773 | ||
50252e4b EB |
1774 | if (poll_iocb_lock_wq(req)) { |
1775 | WRITE_ONCE(req->cancelled, true); | |
1776 | if (!req->work_scheduled) { | |
1777 | schedule_work(&aiocb->poll.work); | |
1778 | req->work_scheduled = true; | |
1779 | } | |
1780 | poll_iocb_unlock_wq(req); | |
1781 | } /* else, the request was force-cancelled by POLLFREE already */ | |
bfe4037e CH |
1782 | |
1783 | return 0; | |
1784 | } | |
1785 | ||
1786 | static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, | |
1787 | void *key) | |
1788 | { | |
1789 | struct poll_iocb *req = container_of(wait, struct poll_iocb, wait); | |
e8693bcf | 1790 | struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll); |
bfe4037e | 1791 | __poll_t mask = key_to_poll(key); |
d3d6a18d | 1792 | unsigned long flags; |
bfe4037e | 1793 | |
bfe4037e | 1794 | /* for instances that support it check for an event match first: */ |
af5c72b1 AV |
1795 | if (mask && !(mask & req->events)) |
1796 | return 0; | |
e8693bcf | 1797 | |
363bee27 EB |
1798 | /* |
1799 | * Complete the request inline if possible. This requires that three | |
1800 | * conditions be met: | |
1801 | * 1. An event mask must have been passed. If a plain wakeup was done | |
1802 | * instead, then mask == 0 and we have to call vfs_poll() to get | |
1803 | * the events, so inline completion isn't possible. | |
1804 | * 2. The completion work must not have already been scheduled. | |
1805 | * 3. ctx_lock must not be busy. We have to use trylock because we | |
1806 | * already hold the waitqueue lock, so this inverts the normal | |
1807 | * locking order. Use irqsave/irqrestore because not all | |
1808 | * filesystems (e.g. fuse) call this function with IRQs disabled, | |
1809 | * yet IRQs have to be disabled before ctx_lock is obtained. | |
1810 | */ | |
1811 | if (mask && !req->work_scheduled && | |
1812 | spin_trylock_irqsave(&iocb->ki_ctx->ctx_lock, flags)) { | |
01d7a356 JA |
1813 | struct kioctx *ctx = iocb->ki_ctx; |
1814 | ||
363bee27 | 1815 | list_del_init(&req->wait.entry); |
af5c72b1 AV |
1816 | list_del(&iocb->ki_list); |
1817 | iocb->ki_res.res = mangle_poll(mask); | |
4b374986 | 1818 | if (iocb->ki_eventfd && !eventfd_signal_allowed()) { |
01d7a356 JA |
1819 | iocb = NULL; |
1820 | INIT_WORK(&req->work, aio_poll_put_work); | |
1821 | schedule_work(&req->work); | |
1822 | } | |
1823 | spin_unlock_irqrestore(&ctx->ctx_lock, flags); | |
1824 | if (iocb) | |
1825 | iocb_put(iocb); | |
af5c72b1 | 1826 | } else { |
363bee27 EB |
1827 | /* |
1828 | * Schedule the completion work if needed. If it was already | |
1829 | * scheduled, record that another wakeup came in. | |
1830 | * | |
1831 | * Don't remove the request from the waitqueue here, as it might | |
1832 | * not actually be complete yet (we won't know until vfs_poll() | |
50252e4b EB |
1833 | * is called), and we must not miss any wakeups. POLLFREE is an |
1834 | * exception to this; see below. | |
363bee27 EB |
1835 | */ |
1836 | if (req->work_scheduled) { | |
1837 | req->work_need_resched = true; | |
1838 | } else { | |
1839 | schedule_work(&req->work); | |
1840 | req->work_scheduled = true; | |
1841 | } | |
50252e4b EB |
1842 | |
1843 | /* | |
1844 | * If the waitqueue is being freed early but we can't complete | |
1845 | * the request inline, we have to tear down the request as best | |
1846 | * we can. That means immediately removing the request from its | |
1847 | * waitqueue and preventing all further accesses to the | |
1848 | * waitqueue via the request. We also need to schedule the | |
1849 | * completion work (done above). Also mark the request as | |
1850 | * cancelled, to potentially skip an unneeded call to ->poll(). | |
1851 | */ | |
1852 | if (mask & POLLFREE) { | |
1853 | WRITE_ONCE(req->cancelled, true); | |
1854 | list_del_init(&req->wait.entry); | |
1855 | ||
1856 | /* | |
1857 | * Careful: this *must* be the last step, since as soon | |
1858 | * as req->head is NULL'ed out, the request can be | |
1859 | * completed and freed, since aio_poll_complete_work() | |
1860 | * will no longer need to take the waitqueue lock. | |
1861 | */ | |
1862 | smp_store_release(&req->head, NULL); | |
1863 | } | |
e8693bcf | 1864 | } |
bfe4037e CH |
1865 | return 1; |
1866 | } | |
1867 | ||
1868 | struct aio_poll_table { | |
1869 | struct poll_table_struct pt; | |
1870 | struct aio_kiocb *iocb; | |
50252e4b | 1871 | bool queued; |
bfe4037e CH |
1872 | int error; |
1873 | }; | |
1874 | ||
1875 | static void | |
1876 | aio_poll_queue_proc(struct file *file, struct wait_queue_head *head, | |
1877 | struct poll_table_struct *p) | |
1878 | { | |
1879 | struct aio_poll_table *pt = container_of(p, struct aio_poll_table, pt); | |
1880 | ||
1881 | /* multiple wait queues per file are not supported */ | |
50252e4b | 1882 | if (unlikely(pt->queued)) { |
bfe4037e CH |
1883 | pt->error = -EINVAL; |
1884 | return; | |
1885 | } | |
1886 | ||
50252e4b | 1887 | pt->queued = true; |
bfe4037e CH |
1888 | pt->error = 0; |
1889 | pt->iocb->poll.head = head; | |
1890 | add_wait_queue(head, &pt->iocb->poll.wait); | |
1891 | } | |
1892 | ||
958c13ce | 1893 | static int aio_poll(struct aio_kiocb *aiocb, const struct iocb *iocb) |
bfe4037e CH |
1894 | { |
1895 | struct kioctx *ctx = aiocb->ki_ctx; | |
1896 | struct poll_iocb *req = &aiocb->poll; | |
1897 | struct aio_poll_table apt; | |
af5c72b1 | 1898 | bool cancel = false; |
bfe4037e CH |
1899 | __poll_t mask; |
1900 | ||
1901 | /* reject any unknown events outside the normal event mask. */ | |
1902 | if ((u16)iocb->aio_buf != iocb->aio_buf) | |
1903 | return -EINVAL; | |
1904 | /* reject fields that are not defined for poll */ | |
1905 | if (iocb->aio_offset || iocb->aio_nbytes || iocb->aio_rw_flags) | |
1906 | return -EINVAL; | |
1907 | ||
1908 | INIT_WORK(&req->work, aio_poll_complete_work); | |
1909 | req->events = demangle_poll(iocb->aio_buf) | EPOLLERR | EPOLLHUP; | |
bfe4037e | 1910 | |
2bc4ca9b | 1911 | req->head = NULL; |
2bc4ca9b | 1912 | req->cancelled = false; |
363bee27 EB |
1913 | req->work_scheduled = false; |
1914 | req->work_need_resched = false; | |
2bc4ca9b | 1915 | |
bfe4037e CH |
1916 | apt.pt._qproc = aio_poll_queue_proc; |
1917 | apt.pt._key = req->events; | |
1918 | apt.iocb = aiocb; | |
50252e4b | 1919 | apt.queued = false; |
bfe4037e CH |
1920 | apt.error = -EINVAL; /* same as no support for IOCB_CMD_POLL */ |
1921 | ||
1922 | /* initialized the list so that we can do list_empty checks */ | |
1923 | INIT_LIST_HEAD(&req->wait.entry); | |
1924 | init_waitqueue_func_entry(&req->wait, aio_poll_wake); | |
1925 | ||
bfe4037e | 1926 | mask = vfs_poll(req->file, &apt.pt) & req->events; |
bfe4037e | 1927 | spin_lock_irq(&ctx->ctx_lock); |
50252e4b EB |
1928 | if (likely(apt.queued)) { |
1929 | bool on_queue = poll_iocb_lock_wq(req); | |
1930 | ||
1931 | if (!on_queue || req->work_scheduled) { | |
363bee27 EB |
1932 | /* |
1933 | * aio_poll_wake() already either scheduled the async | |
1934 | * completion work, or completed the request inline. | |
1935 | */ | |
1936 | if (apt.error) /* unsupported case: multiple queues */ | |
af5c72b1 AV |
1937 | cancel = true; |
1938 | apt.error = 0; | |
1939 | mask = 0; | |
1940 | } | |
1941 | if (mask || apt.error) { | |
363bee27 | 1942 | /* Steal to complete synchronously. */ |
af5c72b1 AV |
1943 | list_del_init(&req->wait.entry); |
1944 | } else if (cancel) { | |
363bee27 | 1945 | /* Cancel if possible (may be too late though). */ |
af5c72b1 | 1946 | WRITE_ONCE(req->cancelled, true); |
50252e4b | 1947 | } else if (on_queue) { |
363bee27 EB |
1948 | /* |
1949 | * Actually waiting for an event, so add the request to | |
1950 | * active_reqs so that it can be cancelled if needed. | |
1951 | */ | |
af5c72b1 AV |
1952 | list_add_tail(&aiocb->ki_list, &ctx->active_reqs); |
1953 | aiocb->ki_cancel = aio_poll_cancel; | |
1954 | } | |
50252e4b EB |
1955 | if (on_queue) |
1956 | poll_iocb_unlock_wq(req); | |
af5c72b1 AV |
1957 | } |
1958 | if (mask) { /* no async, we'd stolen it */ | |
1959 | aiocb->ki_res.res = mangle_poll(mask); | |
bfe4037e | 1960 | apt.error = 0; |
bfe4037e | 1961 | } |
bfe4037e | 1962 | spin_unlock_irq(&ctx->ctx_lock); |
bfe4037e | 1963 | if (mask) |
af5c72b1 AV |
1964 | iocb_put(aiocb); |
1965 | return apt.error; | |
bfe4037e CH |
1966 | } |
1967 | ||
88a6f18b | 1968 | static int __io_submit_one(struct kioctx *ctx, const struct iocb *iocb, |
7316b49c AV |
1969 | struct iocb __user *user_iocb, struct aio_kiocb *req, |
1970 | bool compat) | |
1da177e4 | 1971 | { |
84c4e1f8 | 1972 | req->ki_filp = fget(iocb->aio_fildes); |
84c4e1f8 | 1973 | if (unlikely(!req->ki_filp)) |
7316b49c | 1974 | return -EBADF; |
84c4e1f8 | 1975 | |
88a6f18b | 1976 | if (iocb->aio_flags & IOCB_FLAG_RESFD) { |
74259703 | 1977 | struct eventfd_ctx *eventfd; |
9c3060be DL |
1978 | /* |
1979 | * If the IOCB_FLAG_RESFD flag of aio_flags is set, get an | |
1980 | * instance of the file* now. The file descriptor must be | |
1981 | * an eventfd() fd, and will be signaled for each completed | |
1982 | * event using the eventfd_signal() function. | |
1983 | */ | |
74259703 | 1984 | eventfd = eventfd_ctx_fdget(iocb->aio_resfd); |
7316b49c | 1985 | if (IS_ERR(eventfd)) |
18bfb9c6 | 1986 | return PTR_ERR(eventfd); |
7316b49c | 1987 | |
74259703 | 1988 | req->ki_eventfd = eventfd; |
9830f4be GR |
1989 | } |
1990 | ||
7316b49c | 1991 | if (unlikely(put_user(KIOCB_KEY, &user_iocb->aio_key))) { |
caf4167a | 1992 | pr_debug("EFAULT: aio_key\n"); |
7316b49c | 1993 | return -EFAULT; |
1da177e4 LT |
1994 | } |
1995 | ||
a9339b78 AV |
1996 | req->ki_res.obj = (u64)(unsigned long)user_iocb; |
1997 | req->ki_res.data = iocb->aio_data; | |
1998 | req->ki_res.res = 0; | |
1999 | req->ki_res.res2 = 0; | |
1da177e4 | 2000 | |
88a6f18b | 2001 | switch (iocb->aio_lio_opcode) { |
89319d31 | 2002 | case IOCB_CMD_PREAD: |
7316b49c | 2003 | return aio_read(&req->rw, iocb, false, compat); |
89319d31 | 2004 | case IOCB_CMD_PWRITE: |
7316b49c | 2005 | return aio_write(&req->rw, iocb, false, compat); |
89319d31 | 2006 | case IOCB_CMD_PREADV: |
7316b49c | 2007 | return aio_read(&req->rw, iocb, true, compat); |
89319d31 | 2008 | case IOCB_CMD_PWRITEV: |
7316b49c | 2009 | return aio_write(&req->rw, iocb, true, compat); |
a3c0d439 | 2010 | case IOCB_CMD_FSYNC: |
7316b49c | 2011 | return aio_fsync(&req->fsync, iocb, false); |
a3c0d439 | 2012 | case IOCB_CMD_FDSYNC: |
7316b49c | 2013 | return aio_fsync(&req->fsync, iocb, true); |
bfe4037e | 2014 | case IOCB_CMD_POLL: |
7316b49c | 2015 | return aio_poll(req, iocb); |
89319d31 | 2016 | default: |
88a6f18b | 2017 | pr_debug("invalid aio operation %d\n", iocb->aio_lio_opcode); |
7316b49c | 2018 | return -EINVAL; |
89319d31 | 2019 | } |
1da177e4 LT |
2020 | } |
2021 | ||
88a6f18b JA |
2022 | static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, |
2023 | bool compat) | |
2024 | { | |
7316b49c | 2025 | struct aio_kiocb *req; |
88a6f18b | 2026 | struct iocb iocb; |
7316b49c | 2027 | int err; |
88a6f18b JA |
2028 | |
2029 | if (unlikely(copy_from_user(&iocb, user_iocb, sizeof(iocb)))) | |
2030 | return -EFAULT; | |
2031 | ||
7316b49c AV |
2032 | /* enforce forwards compatibility on users */ |
2033 | if (unlikely(iocb.aio_reserved2)) { | |
2034 | pr_debug("EINVAL: reserve field set\n"); | |
2035 | return -EINVAL; | |
2036 | } | |
2037 | ||
2038 | /* prevent overflows */ | |
2039 | if (unlikely( | |
2040 | (iocb.aio_buf != (unsigned long)iocb.aio_buf) || | |
2041 | (iocb.aio_nbytes != (size_t)iocb.aio_nbytes) || | |
2042 | ((ssize_t)iocb.aio_nbytes < 0) | |
2043 | )) { | |
2044 | pr_debug("EINVAL: overflow check\n"); | |
2045 | return -EINVAL; | |
2046 | } | |
2047 | ||
2048 | req = aio_get_req(ctx); | |
2049 | if (unlikely(!req)) | |
2050 | return -EAGAIN; | |
2051 | ||
2052 | err = __io_submit_one(ctx, &iocb, user_iocb, req, compat); | |
2053 | ||
2054 | /* Done with the synchronous reference */ | |
2055 | iocb_put(req); | |
2056 | ||
2057 | /* | |
2058 | * If err is 0, we'd either done aio_complete() ourselves or have | |
2059 | * arranged for that to be done asynchronously. Anything non-zero | |
2060 | * means that we need to destroy req ourselves. | |
2061 | */ | |
2062 | if (unlikely(err)) { | |
2063 | iocb_destroy(req); | |
2064 | put_reqs_available(ctx, 1); | |
2065 | } | |
2066 | return err; | |
88a6f18b JA |
2067 | } |
2068 | ||
67ba049f AV |
2069 | /* sys_io_submit: |
2070 | * Queue the nr iocbs pointed to by iocbpp for processing. Returns | |
2071 | * the number of iocbs queued. May return -EINVAL if the aio_context | |
2072 | * specified by ctx_id is invalid, if nr is < 0, if the iocb at | |
2073 | * *iocbpp[0] is not properly initialized, if the operation specified | |
2074 | * is invalid for the file descriptor in the iocb. May fail with | |
2075 | * -EFAULT if any of the data structures point to invalid data. May | |
2076 | * fail with -EBADF if the file descriptor specified in the first | |
2077 | * iocb is invalid. May fail with -EAGAIN if insufficient resources | |
2078 | * are available to queue any iocbs. Will return 0 if nr is 0. Will | |
2079 | * fail with -ENOSYS if not implemented. | |
2080 | */ | |
2081 | SYSCALL_DEFINE3(io_submit, aio_context_t, ctx_id, long, nr, | |
2082 | struct iocb __user * __user *, iocbpp) | |
1da177e4 LT |
2083 | { |
2084 | struct kioctx *ctx; | |
2085 | long ret = 0; | |
080d676d | 2086 | int i = 0; |
9f5b9425 | 2087 | struct blk_plug plug; |
1da177e4 LT |
2088 | |
2089 | if (unlikely(nr < 0)) | |
2090 | return -EINVAL; | |
2091 | ||
1da177e4 LT |
2092 | ctx = lookup_ioctx(ctx_id); |
2093 | if (unlikely(!ctx)) { | |
caf4167a | 2094 | pr_debug("EINVAL: invalid context id\n"); |
1da177e4 LT |
2095 | return -EINVAL; |
2096 | } | |
2097 | ||
1da92779 AV |
2098 | if (nr > ctx->nr_events) |
2099 | nr = ctx->nr_events; | |
2100 | ||
a79d40e9 JA |
2101 | if (nr > AIO_PLUG_THRESHOLD) |
2102 | blk_start_plug(&plug); | |
67ba049f | 2103 | for (i = 0; i < nr; i++) { |
1da177e4 | 2104 | struct iocb __user *user_iocb; |
1da177e4 | 2105 | |
67ba049f | 2106 | if (unlikely(get_user(user_iocb, iocbpp + i))) { |
1da177e4 LT |
2107 | ret = -EFAULT; |
2108 | break; | |
2109 | } | |
2110 | ||
67ba049f | 2111 | ret = io_submit_one(ctx, user_iocb, false); |
1da177e4 LT |
2112 | if (ret) |
2113 | break; | |
2114 | } | |
a79d40e9 JA |
2115 | if (nr > AIO_PLUG_THRESHOLD) |
2116 | blk_finish_plug(&plug); | |
1da177e4 | 2117 | |
723be6e3 | 2118 | percpu_ref_put(&ctx->users); |
1da177e4 LT |
2119 | return i ? i : ret; |
2120 | } | |
2121 | ||
c00d2c7e | 2122 | #ifdef CONFIG_COMPAT |
c00d2c7e | 2123 | COMPAT_SYSCALL_DEFINE3(io_submit, compat_aio_context_t, ctx_id, |
67ba049f | 2124 | int, nr, compat_uptr_t __user *, iocbpp) |
c00d2c7e | 2125 | { |
67ba049f AV |
2126 | struct kioctx *ctx; |
2127 | long ret = 0; | |
2128 | int i = 0; | |
2129 | struct blk_plug plug; | |
c00d2c7e AV |
2130 | |
2131 | if (unlikely(nr < 0)) | |
2132 | return -EINVAL; | |
2133 | ||
67ba049f AV |
2134 | ctx = lookup_ioctx(ctx_id); |
2135 | if (unlikely(!ctx)) { | |
2136 | pr_debug("EINVAL: invalid context id\n"); | |
2137 | return -EINVAL; | |
2138 | } | |
2139 | ||
1da92779 AV |
2140 | if (nr > ctx->nr_events) |
2141 | nr = ctx->nr_events; | |
2142 | ||
a79d40e9 JA |
2143 | if (nr > AIO_PLUG_THRESHOLD) |
2144 | blk_start_plug(&plug); | |
67ba049f AV |
2145 | for (i = 0; i < nr; i++) { |
2146 | compat_uptr_t user_iocb; | |
2147 | ||
2148 | if (unlikely(get_user(user_iocb, iocbpp + i))) { | |
2149 | ret = -EFAULT; | |
2150 | break; | |
2151 | } | |
2152 | ||
2153 | ret = io_submit_one(ctx, compat_ptr(user_iocb), true); | |
2154 | if (ret) | |
2155 | break; | |
2156 | } | |
a79d40e9 JA |
2157 | if (nr > AIO_PLUG_THRESHOLD) |
2158 | blk_finish_plug(&plug); | |
67ba049f AV |
2159 | |
2160 | percpu_ref_put(&ctx->users); | |
2161 | return i ? i : ret; | |
c00d2c7e AV |
2162 | } |
2163 | #endif | |
2164 | ||
1da177e4 | 2165 | /* sys_io_cancel: |
28468cbe BVA |
2166 | * Attempts to cancel an iocb previously passed to io_submit. If |
2167 | * the operation is successfully cancelled, the resulting event is | |
2168 | * copied into the memory pointed to by result without being placed | |
2169 | * into the completion queue and 0 is returned. May fail with | |
2170 | * -EFAULT if any of the data structures pointed to are invalid. | |
2171 | * May fail with -EINVAL if aio_context specified by ctx_id is | |
2172 | * invalid. May fail with -EAGAIN if the iocb specified was not | |
2173 | * cancelled. Will fail with -ENOSYS if not implemented. | |
1da177e4 | 2174 | */ |
002c8976 HC |
2175 | SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb, |
2176 | struct io_event __user *, result) | |
1da177e4 | 2177 | { |
1da177e4 | 2178 | struct kioctx *ctx; |
04b2fa9f | 2179 | struct aio_kiocb *kiocb; |
888933f8 | 2180 | int ret = -EINVAL; |
1da177e4 | 2181 | u32 key; |
a9339b78 | 2182 | u64 obj = (u64)(unsigned long)iocb; |
1da177e4 | 2183 | |
f3a2752a | 2184 | if (unlikely(get_user(key, &iocb->aio_key))) |
1da177e4 | 2185 | return -EFAULT; |
f3a2752a CH |
2186 | if (unlikely(key != KIOCB_KEY)) |
2187 | return -EINVAL; | |
1da177e4 LT |
2188 | |
2189 | ctx = lookup_ioctx(ctx_id); | |
2190 | if (unlikely(!ctx)) | |
2191 | return -EINVAL; | |
2192 | ||
2193 | spin_lock_irq(&ctx->ctx_lock); | |
833f4154 | 2194 | list_for_each_entry(kiocb, &ctx->active_reqs, ki_list) { |
a9339b78 | 2195 | if (kiocb->ki_res.obj == obj) { |
833f4154 AV |
2196 | ret = kiocb->ki_cancel(&kiocb->rw); |
2197 | list_del_init(&kiocb->ki_list); | |
2198 | break; | |
2199 | } | |
888933f8 | 2200 | } |
1da177e4 LT |
2201 | spin_unlock_irq(&ctx->ctx_lock); |
2202 | ||
28468cbe BVA |
2203 | if (!ret) { |
2204 | /* | |
2205 | * The result argument is no longer used - the io_event is | |
2206 | * always delivered via the ring buffer. -EINPROGRESS indicates | |
2207 | * cancellation is progress: | |
2208 | */ | |
2209 | ret = -EINPROGRESS; | |
2210 | } | |
1da177e4 | 2211 | |
723be6e3 | 2212 | percpu_ref_put(&ctx->users); |
1da177e4 LT |
2213 | |
2214 | return ret; | |
2215 | } | |
2216 | ||
fa2e62a5 DD |
2217 | static long do_io_getevents(aio_context_t ctx_id, |
2218 | long min_nr, | |
2219 | long nr, | |
2220 | struct io_event __user *events, | |
2221 | struct timespec64 *ts) | |
2222 | { | |
2223 | ktime_t until = ts ? timespec64_to_ktime(*ts) : KTIME_MAX; | |
2224 | struct kioctx *ioctx = lookup_ioctx(ctx_id); | |
2225 | long ret = -EINVAL; | |
2226 | ||
2227 | if (likely(ioctx)) { | |
2228 | if (likely(min_nr <= nr && min_nr >= 0)) | |
2229 | ret = read_events(ioctx, min_nr, nr, events, until); | |
2230 | percpu_ref_put(&ioctx->users); | |
2231 | } | |
2232 | ||
2233 | return ret; | |
2234 | } | |
2235 | ||
1da177e4 LT |
2236 | /* io_getevents: |
2237 | * Attempts to read at least min_nr events and up to nr events from | |
642b5123 ST |
2238 | * the completion queue for the aio_context specified by ctx_id. If |
2239 | * it succeeds, the number of read events is returned. May fail with | |
2240 | * -EINVAL if ctx_id is invalid, if min_nr is out of range, if nr is | |
2241 | * out of range, if timeout is out of range. May fail with -EFAULT | |
2242 | * if any of the memory specified is invalid. May return 0 or | |
2243 | * < min_nr if the timeout specified by timeout has elapsed | |
2244 | * before sufficient events are available, where timeout == NULL | |
2245 | * specifies an infinite timeout. Note that the timeout pointed to by | |
6900807c | 2246 | * timeout is relative. Will fail with -ENOSYS if not implemented. |
1da177e4 | 2247 | */ |
3ca47e95 | 2248 | #ifdef CONFIG_64BIT |
7a35397f | 2249 | |
002c8976 HC |
2250 | SYSCALL_DEFINE5(io_getevents, aio_context_t, ctx_id, |
2251 | long, min_nr, | |
2252 | long, nr, | |
2253 | struct io_event __user *, events, | |
7a35397f | 2254 | struct __kernel_timespec __user *, timeout) |
1da177e4 | 2255 | { |
fa2e62a5 | 2256 | struct timespec64 ts; |
7a074e96 CH |
2257 | int ret; |
2258 | ||
2259 | if (timeout && unlikely(get_timespec64(&ts, timeout))) | |
2260 | return -EFAULT; | |
2261 | ||
2262 | ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL); | |
2263 | if (!ret && signal_pending(current)) | |
2264 | ret = -EINTR; | |
2265 | return ret; | |
2266 | } | |
1da177e4 | 2267 | |
7a35397f DD |
2268 | #endif |
2269 | ||
9ba546c0 CH |
2270 | struct __aio_sigset { |
2271 | const sigset_t __user *sigmask; | |
2272 | size_t sigsetsize; | |
2273 | }; | |
2274 | ||
7a074e96 CH |
2275 | SYSCALL_DEFINE6(io_pgetevents, |
2276 | aio_context_t, ctx_id, | |
2277 | long, min_nr, | |
2278 | long, nr, | |
2279 | struct io_event __user *, events, | |
7a35397f | 2280 | struct __kernel_timespec __user *, timeout, |
7a074e96 CH |
2281 | const struct __aio_sigset __user *, usig) |
2282 | { | |
2283 | struct __aio_sigset ksig = { NULL, }; | |
7a074e96 | 2284 | struct timespec64 ts; |
97abc889 | 2285 | bool interrupted; |
7a074e96 CH |
2286 | int ret; |
2287 | ||
2288 | if (timeout && unlikely(get_timespec64(&ts, timeout))) | |
2289 | return -EFAULT; | |
2290 | ||
2291 | if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) | |
2292 | return -EFAULT; | |
2293 | ||
b772434b | 2294 | ret = set_user_sigmask(ksig.sigmask, ksig.sigsetsize); |
7a35397f DD |
2295 | if (ret) |
2296 | return ret; | |
7a074e96 CH |
2297 | |
2298 | ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL); | |
97abc889 ON |
2299 | |
2300 | interrupted = signal_pending(current); | |
b772434b | 2301 | restore_saved_sigmask_unless(interrupted); |
97abc889 | 2302 | if (interrupted && !ret) |
7a35397f | 2303 | ret = -ERESTARTNOHAND; |
7a074e96 | 2304 | |
7a35397f DD |
2305 | return ret; |
2306 | } | |
2307 | ||
2308 | #if defined(CONFIG_COMPAT_32BIT_TIME) && !defined(CONFIG_64BIT) | |
2309 | ||
2310 | SYSCALL_DEFINE6(io_pgetevents_time32, | |
2311 | aio_context_t, ctx_id, | |
2312 | long, min_nr, | |
2313 | long, nr, | |
2314 | struct io_event __user *, events, | |
2315 | struct old_timespec32 __user *, timeout, | |
2316 | const struct __aio_sigset __user *, usig) | |
2317 | { | |
2318 | struct __aio_sigset ksig = { NULL, }; | |
7a35397f | 2319 | struct timespec64 ts; |
97abc889 | 2320 | bool interrupted; |
7a35397f DD |
2321 | int ret; |
2322 | ||
2323 | if (timeout && unlikely(get_old_timespec32(&ts, timeout))) | |
2324 | return -EFAULT; | |
2325 | ||
2326 | if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) | |
2327 | return -EFAULT; | |
2328 | ||
ded653cc | 2329 | |
b772434b | 2330 | ret = set_user_sigmask(ksig.sigmask, ksig.sigsetsize); |
ded653cc DD |
2331 | if (ret) |
2332 | return ret; | |
7a074e96 CH |
2333 | |
2334 | ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL); | |
97abc889 ON |
2335 | |
2336 | interrupted = signal_pending(current); | |
b772434b | 2337 | restore_saved_sigmask_unless(interrupted); |
97abc889 | 2338 | if (interrupted && !ret) |
854a6ed5 | 2339 | ret = -ERESTARTNOHAND; |
fa2e62a5 | 2340 | |
7a074e96 | 2341 | return ret; |
1da177e4 | 2342 | } |
c00d2c7e | 2343 | |
7a35397f DD |
2344 | #endif |
2345 | ||
2346 | #if defined(CONFIG_COMPAT_32BIT_TIME) | |
2347 | ||
8dabe724 AB |
2348 | SYSCALL_DEFINE5(io_getevents_time32, __u32, ctx_id, |
2349 | __s32, min_nr, | |
2350 | __s32, nr, | |
2351 | struct io_event __user *, events, | |
2352 | struct old_timespec32 __user *, timeout) | |
c00d2c7e | 2353 | { |
fa2e62a5 | 2354 | struct timespec64 t; |
7a074e96 CH |
2355 | int ret; |
2356 | ||
9afc5eee | 2357 | if (timeout && get_old_timespec32(&t, timeout)) |
7a074e96 CH |
2358 | return -EFAULT; |
2359 | ||
2360 | ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL); | |
2361 | if (!ret && signal_pending(current)) | |
2362 | ret = -EINTR; | |
2363 | return ret; | |
2364 | } | |
2365 | ||
7a35397f DD |
2366 | #endif |
2367 | ||
2368 | #ifdef CONFIG_COMPAT | |
c00d2c7e | 2369 | |
7a074e96 | 2370 | struct __compat_aio_sigset { |
97eba80f | 2371 | compat_uptr_t sigmask; |
7a074e96 CH |
2372 | compat_size_t sigsetsize; |
2373 | }; | |
2374 | ||
7a35397f DD |
2375 | #if defined(CONFIG_COMPAT_32BIT_TIME) |
2376 | ||
7a074e96 CH |
2377 | COMPAT_SYSCALL_DEFINE6(io_pgetevents, |
2378 | compat_aio_context_t, ctx_id, | |
2379 | compat_long_t, min_nr, | |
2380 | compat_long_t, nr, | |
2381 | struct io_event __user *, events, | |
9afc5eee | 2382 | struct old_timespec32 __user *, timeout, |
7a074e96 CH |
2383 | const struct __compat_aio_sigset __user *, usig) |
2384 | { | |
97eba80f | 2385 | struct __compat_aio_sigset ksig = { 0, }; |
7a074e96 | 2386 | struct timespec64 t; |
97abc889 | 2387 | bool interrupted; |
7a074e96 CH |
2388 | int ret; |
2389 | ||
9afc5eee | 2390 | if (timeout && get_old_timespec32(&t, timeout)) |
7a074e96 CH |
2391 | return -EFAULT; |
2392 | ||
2393 | if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) | |
2394 | return -EFAULT; | |
2395 | ||
97eba80f | 2396 | ret = set_compat_user_sigmask(compat_ptr(ksig.sigmask), ksig.sigsetsize); |
ded653cc DD |
2397 | if (ret) |
2398 | return ret; | |
c00d2c7e | 2399 | |
7a074e96 | 2400 | ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL); |
97abc889 ON |
2401 | |
2402 | interrupted = signal_pending(current); | |
b772434b | 2403 | restore_saved_sigmask_unless(interrupted); |
97abc889 | 2404 | if (interrupted && !ret) |
854a6ed5 | 2405 | ret = -ERESTARTNOHAND; |
fa2e62a5 | 2406 | |
7a074e96 | 2407 | return ret; |
c00d2c7e | 2408 | } |
7a35397f DD |
2409 | |
2410 | #endif | |
2411 | ||
2412 | COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64, | |
2413 | compat_aio_context_t, ctx_id, | |
2414 | compat_long_t, min_nr, | |
2415 | compat_long_t, nr, | |
2416 | struct io_event __user *, events, | |
2417 | struct __kernel_timespec __user *, timeout, | |
2418 | const struct __compat_aio_sigset __user *, usig) | |
2419 | { | |
97eba80f | 2420 | struct __compat_aio_sigset ksig = { 0, }; |
7a35397f | 2421 | struct timespec64 t; |
97abc889 | 2422 | bool interrupted; |
7a35397f DD |
2423 | int ret; |
2424 | ||
2425 | if (timeout && get_timespec64(&t, timeout)) | |
2426 | return -EFAULT; | |
2427 | ||
2428 | if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) | |
2429 | return -EFAULT; | |
2430 | ||
97eba80f | 2431 | ret = set_compat_user_sigmask(compat_ptr(ksig.sigmask), ksig.sigsetsize); |
7a35397f DD |
2432 | if (ret) |
2433 | return ret; | |
2434 | ||
2435 | ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL); | |
97abc889 ON |
2436 | |
2437 | interrupted = signal_pending(current); | |
b772434b | 2438 | restore_saved_sigmask_unless(interrupted); |
97abc889 | 2439 | if (interrupted && !ret) |
7a35397f | 2440 | ret = -ERESTARTNOHAND; |
fa2e62a5 | 2441 | |
7a074e96 | 2442 | return ret; |
c00d2c7e AV |
2443 | } |
2444 | #endif |