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10
11#define pr_fmt(fmt) "%s: " fmt, __func__
12
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/errno.h>
16#include <linux/time.h>
17#include <linux/aio_abi.h>
18#include <linux/export.h>
19#include <linux/syscalls.h>
20#include <linux/backing-dev.h>
21#include <linux/uio.h>
22
23#include <linux/sched/signal.h>
24#include <linux/fs.h>
25#include <linux/file.h>
26#include <linux/mm.h>
27#include <linux/mman.h>
28#include <linux/mmu_context.h>
29#include <linux/percpu.h>
30#include <linux/slab.h>
31#include <linux/timer.h>
32#include <linux/aio.h>
33#include <linux/highmem.h>
34#include <linux/workqueue.h>
35#include <linux/security.h>
36#include <linux/eventfd.h>
37#include <linux/blkdev.h>
38#include <linux/compat.h>
39#include <linux/migrate.h>
40#include <linux/ramfs.h>
41#include <linux/percpu-refcount.h>
42#include <linux/mount.h>
43
44#include <asm/kmap_types.h>
45#include <linux/uaccess.h>
46
47#include "internal.h"
48
49#define AIO_RING_MAGIC 0xa10a10a1
50#define AIO_RING_COMPAT_FEATURES 1
51#define AIO_RING_INCOMPAT_FEATURES 0
52struct aio_ring {
53 unsigned id;
54 unsigned nr;
55 unsigned head;
56
57 unsigned tail;
58
59 unsigned magic;
60 unsigned compat_features;
61 unsigned incompat_features;
62 unsigned header_length;
63
64
65 struct io_event io_events[0];
66};
67
68#define AIO_RING_PAGES 8
69
70struct kioctx_table {
71 struct rcu_head rcu;
72 unsigned nr;
73 struct kioctx __rcu *table[];
74};
75
76struct kioctx_cpu {
77 unsigned reqs_available;
78};
79
80struct ctx_rq_wait {
81 struct completion comp;
82 atomic_t count;
83};
84
85struct kioctx {
86 struct percpu_ref users;
87 atomic_t dead;
88
89 struct percpu_ref reqs;
90
91 unsigned long user_id;
92
93 struct __percpu kioctx_cpu *cpu;
94
95
96
97
98
99 unsigned req_batch;
100
101
102
103
104
105
106
107 unsigned max_reqs;
108
109
110 unsigned nr_events;
111
112 unsigned long mmap_base;
113 unsigned long mmap_size;
114
115 struct page **ring_pages;
116 long nr_pages;
117
118 struct rcu_work free_rwork;
119
120
121
122
123 struct ctx_rq_wait *rq_wait;
124
125 struct {
126
127
128
129
130
131
132
133
134 atomic_t reqs_available;
135 } ____cacheline_aligned_in_smp;
136
137 struct {
138 spinlock_t ctx_lock;
139 struct list_head active_reqs;
140 } ____cacheline_aligned_in_smp;
141
142 struct {
143 struct mutex ring_lock;
144 wait_queue_head_t wait;
145 } ____cacheline_aligned_in_smp;
146
147 struct {
148 unsigned tail;
149 unsigned completed_events;
150 spinlock_t completion_lock;
151 } ____cacheline_aligned_in_smp;
152
153 struct page *internal_pages[AIO_RING_PAGES];
154 struct file *aio_ring_file;
155
156 unsigned id;
157};
158
159
160
161
162
163
164
165
166
167
168
169
170#define KIOCB_CANCELLED ((void *) (~0ULL))
171
172struct aio_kiocb {
173 struct kiocb common;
174
175 struct kioctx *ki_ctx;
176 kiocb_cancel_fn *ki_cancel;
177
178 struct iocb __user *ki_user_iocb;
179 __u64 ki_user_data;
180
181 struct list_head ki_list;
182
183
184
185
186
187
188 struct eventfd_ctx *ki_eventfd;
189};
190
191
192static DEFINE_SPINLOCK(aio_nr_lock);
193unsigned long aio_nr;
194unsigned long aio_max_nr = 0x10000;
195
196
197static struct kmem_cache *kiocb_cachep;
198static struct kmem_cache *kioctx_cachep;
199
200static struct vfsmount *aio_mnt;
201
202static const struct file_operations aio_ring_fops;
203static const struct address_space_operations aio_ctx_aops;
204
205static struct file *aio_private_file(struct kioctx *ctx, loff_t nr_pages)
206{
207 struct qstr this = QSTR_INIT("[aio]", 5);
208 struct file *file;
209 struct path path;
210 struct inode *inode = alloc_anon_inode(aio_mnt->mnt_sb);
211 if (IS_ERR(inode))
212 return ERR_CAST(inode);
213
214 inode->i_mapping->a_ops = &aio_ctx_aops;
215 inode->i_mapping->private_data = ctx;
216 inode->i_size = PAGE_SIZE * nr_pages;
217
218 path.dentry = d_alloc_pseudo(aio_mnt->mnt_sb, &this);
219 if (!path.dentry) {
220 iput(inode);
221 return ERR_PTR(-ENOMEM);
222 }
223 path.mnt = mntget(aio_mnt);
224
225 d_instantiate(path.dentry, inode);
226 file = alloc_file(&path, FMODE_READ | FMODE_WRITE, &aio_ring_fops);
227 if (IS_ERR(file)) {
228 path_put(&path);
229 return file;
230 }
231
232 file->f_flags = O_RDWR;
233 return file;
234}
235
236static struct dentry *aio_mount(struct file_system_type *fs_type,
237 int flags, const char *dev_name, void *data)
238{
239 static const struct dentry_operations ops = {
240 .d_dname = simple_dname,
241 };
242 struct dentry *root = mount_pseudo(fs_type, "aio:", NULL, &ops,
243 AIO_RING_MAGIC);
244
245 if (!IS_ERR(root))
246 root->d_sb->s_iflags |= SB_I_NOEXEC;
247 return root;
248}
249
250
251
252
253
254static int __init aio_setup(void)
255{
256 static struct file_system_type aio_fs = {
257 .name = "aio",
258 .mount = aio_mount,
259 .kill_sb = kill_anon_super,
260 };
261 aio_mnt = kern_mount(&aio_fs);
262 if (IS_ERR(aio_mnt))
263 panic("Failed to create aio fs mount.");
264
265 kiocb_cachep = KMEM_CACHE(aio_kiocb, SLAB_HWCACHE_ALIGN|SLAB_PANIC);
266 kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC);
267
268 pr_debug("sizeof(struct page) = %zu\n", sizeof(struct page));
269
270 return 0;
271}
272__initcall(aio_setup);
273
274static void put_aio_ring_file(struct kioctx *ctx)
275{
276 struct file *aio_ring_file = ctx->aio_ring_file;
277 struct address_space *i_mapping;
278
279 if (aio_ring_file) {
280 truncate_setsize(file_inode(aio_ring_file), 0);
281
282
283 i_mapping = aio_ring_file->f_mapping;
284 spin_lock(&i_mapping->private_lock);
285 i_mapping->private_data = NULL;
286 ctx->aio_ring_file = NULL;
287 spin_unlock(&i_mapping->private_lock);
288
289 fput(aio_ring_file);
290 }
291}
292
293static void aio_free_ring(struct kioctx *ctx)
294{
295 int i;
296
297
298
299
300 put_aio_ring_file(ctx);
301
302 for (i = 0; i < ctx->nr_pages; i++) {
303 struct page *page;
304 pr_debug("pid(%d) [%d] page->count=%d\n", current->pid, i,
305 page_count(ctx->ring_pages[i]));
306 page = ctx->ring_pages[i];
307 if (!page)
308 continue;
309 ctx->ring_pages[i] = NULL;
310 put_page(page);
311 }
312
313 if (ctx->ring_pages && ctx->ring_pages != ctx->internal_pages) {
314 kfree(ctx->ring_pages);
315 ctx->ring_pages = NULL;
316 }
317}
318
319static int aio_ring_mremap(struct vm_area_struct *vma)
320{
321 struct file *file = vma->vm_file;
322 struct mm_struct *mm = vma->vm_mm;
323 struct kioctx_table *table;
324 int i, res = -EINVAL;
325
326 spin_lock(&mm->ioctx_lock);
327 rcu_read_lock();
328 table = rcu_dereference(mm->ioctx_table);
329 for (i = 0; i < table->nr; i++) {
330 struct kioctx *ctx;
331
332 ctx = rcu_dereference(table->table[i]);
333 if (ctx && ctx->aio_ring_file == file) {
334 if (!atomic_read(&ctx->dead)) {
335 ctx->user_id = ctx->mmap_base = vma->vm_start;
336 res = 0;
337 }
338 break;
339 }
340 }
341
342 rcu_read_unlock();
343 spin_unlock(&mm->ioctx_lock);
344 return res;
345}
346
347static const struct vm_operations_struct aio_ring_vm_ops = {
348 .mremap = aio_ring_mremap,
349#if IS_ENABLED(CONFIG_MMU)
350 .fault = filemap_fault,
351 .map_pages = filemap_map_pages,
352 .page_mkwrite = filemap_page_mkwrite,
353#endif
354};
355
356static int aio_ring_mmap(struct file *file, struct vm_area_struct *vma)
357{
358 vma->vm_flags |= VM_DONTEXPAND;
359 vma->vm_ops = &aio_ring_vm_ops;
360 return 0;
361}
362
363static const struct file_operations aio_ring_fops = {
364 .mmap = aio_ring_mmap,
365};
366
367#if IS_ENABLED(CONFIG_MIGRATION)
368static int aio_migratepage(struct address_space *mapping, struct page *new,
369 struct page *old, enum migrate_mode mode)
370{
371 struct kioctx *ctx;
372 unsigned long flags;
373 pgoff_t idx;
374 int rc;
375
376
377
378
379
380
381 if (mode == MIGRATE_SYNC_NO_COPY)
382 return -EINVAL;
383
384 rc = 0;
385
386
387 spin_lock(&mapping->private_lock);
388 ctx = mapping->private_data;
389 if (!ctx) {
390 rc = -EINVAL;
391 goto out;
392 }
393
394
395
396
397
398 if (!mutex_trylock(&ctx->ring_lock)) {
399 rc = -EAGAIN;
400 goto out;
401 }
402
403 idx = old->index;
404 if (idx < (pgoff_t)ctx->nr_pages) {
405
406 if (ctx->ring_pages[idx] != old)
407 rc = -EAGAIN;
408 } else
409 rc = -EINVAL;
410
411 if (rc != 0)
412 goto out_unlock;
413
414
415 BUG_ON(PageWriteback(old));
416 get_page(new);
417
418 rc = migrate_page_move_mapping(mapping, new, old, NULL, mode, 1);
419 if (rc != MIGRATEPAGE_SUCCESS) {
420 put_page(new);
421 goto out_unlock;
422 }
423
424
425
426
427
428 spin_lock_irqsave(&ctx->completion_lock, flags);
429 migrate_page_copy(new, old);
430 BUG_ON(ctx->ring_pages[idx] != old);
431 ctx->ring_pages[idx] = new;
432 spin_unlock_irqrestore(&ctx->completion_lock, flags);
433
434
435 put_page(old);
436
437out_unlock:
438 mutex_unlock(&ctx->ring_lock);
439out:
440 spin_unlock(&mapping->private_lock);
441 return rc;
442}
443#endif
444
445static const struct address_space_operations aio_ctx_aops = {
446 .set_page_dirty = __set_page_dirty_no_writeback,
447#if IS_ENABLED(CONFIG_MIGRATION)
448 .migratepage = aio_migratepage,
449#endif
450};
451
452static int aio_setup_ring(struct kioctx *ctx, unsigned int nr_events)
453{
454 struct aio_ring *ring;
455 struct mm_struct *mm = current->mm;
456 unsigned long size, unused;
457 int nr_pages;
458 int i;
459 struct file *file;
460
461
462 nr_events += 2;
463
464 size = sizeof(struct aio_ring);
465 size += sizeof(struct io_event) * nr_events;
466
467 nr_pages = PFN_UP(size);
468 if (nr_pages < 0)
469 return -EINVAL;
470
471 file = aio_private_file(ctx, nr_pages);
472 if (IS_ERR(file)) {
473 ctx->aio_ring_file = NULL;
474 return -ENOMEM;
475 }
476
477 ctx->aio_ring_file = file;
478 nr_events = (PAGE_SIZE * nr_pages - sizeof(struct aio_ring))
479 / sizeof(struct io_event);
480
481 ctx->ring_pages = ctx->internal_pages;
482 if (nr_pages > AIO_RING_PAGES) {
483 ctx->ring_pages = kcalloc(nr_pages, sizeof(struct page *),
484 GFP_KERNEL);
485 if (!ctx->ring_pages) {
486 put_aio_ring_file(ctx);
487 return -ENOMEM;
488 }
489 }
490
491 for (i = 0; i < nr_pages; i++) {
492 struct page *page;
493 page = find_or_create_page(file->f_mapping,
494 i, GFP_HIGHUSER | __GFP_ZERO);
495 if (!page)
496 break;
497 pr_debug("pid(%d) page[%d]->count=%d\n",
498 current->pid, i, page_count(page));
499 SetPageUptodate(page);
500 unlock_page(page);
501
502 ctx->ring_pages[i] = page;
503 }
504 ctx->nr_pages = i;
505
506 if (unlikely(i != nr_pages)) {
507 aio_free_ring(ctx);
508 return -ENOMEM;
509 }
510
511 ctx->mmap_size = nr_pages * PAGE_SIZE;
512 pr_debug("attempting mmap of %lu bytes\n", ctx->mmap_size);
513
514 if (down_write_killable(&mm->mmap_sem)) {
515 ctx->mmap_size = 0;
516 aio_free_ring(ctx);
517 return -EINTR;
518 }
519
520 ctx->mmap_base = do_mmap_pgoff(ctx->aio_ring_file, 0, ctx->mmap_size,
521 PROT_READ | PROT_WRITE,
522 MAP_SHARED, 0, &unused, NULL);
523 up_write(&mm->mmap_sem);
524 if (IS_ERR((void *)ctx->mmap_base)) {
525 ctx->mmap_size = 0;
526 aio_free_ring(ctx);
527 return -ENOMEM;
528 }
529
530 pr_debug("mmap address: 0x%08lx\n", ctx->mmap_base);
531
532 ctx->user_id = ctx->mmap_base;
533 ctx->nr_events = nr_events;
534
535 ring = kmap_atomic(ctx->ring_pages[0]);
536 ring->nr = nr_events;
537 ring->id = ~0U;
538 ring->head = ring->tail = 0;
539 ring->magic = AIO_RING_MAGIC;
540 ring->compat_features = AIO_RING_COMPAT_FEATURES;
541 ring->incompat_features = AIO_RING_INCOMPAT_FEATURES;
542 ring->header_length = sizeof(struct aio_ring);
543 kunmap_atomic(ring);
544 flush_dcache_page(ctx->ring_pages[0]);
545
546 return 0;
547}
548
549#define AIO_EVENTS_PER_PAGE (PAGE_SIZE / sizeof(struct io_event))
550#define AIO_EVENTS_FIRST_PAGE ((PAGE_SIZE - sizeof(struct aio_ring)) / sizeof(struct io_event))
551#define AIO_EVENTS_OFFSET (AIO_EVENTS_PER_PAGE - AIO_EVENTS_FIRST_PAGE)
552
553void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel)
554{
555 struct aio_kiocb *req = container_of(iocb, struct aio_kiocb, common);
556 struct kioctx *ctx = req->ki_ctx;
557 unsigned long flags;
558
559 spin_lock_irqsave(&ctx->ctx_lock, flags);
560
561 if (!req->ki_list.next)
562 list_add(&req->ki_list, &ctx->active_reqs);
563
564 req->ki_cancel = cancel;
565
566 spin_unlock_irqrestore(&ctx->ctx_lock, flags);
567}
568EXPORT_SYMBOL(kiocb_set_cancel_fn);
569
570static int kiocb_cancel(struct aio_kiocb *kiocb)
571{
572 kiocb_cancel_fn *old, *cancel;
573
574
575
576
577
578
579 cancel = READ_ONCE(kiocb->ki_cancel);
580 do {
581 if (!cancel || cancel == KIOCB_CANCELLED)
582 return -EINVAL;
583
584 old = cancel;
585 cancel = cmpxchg(&kiocb->ki_cancel, old, KIOCB_CANCELLED);
586 } while (cancel != old);
587
588 return cancel(&kiocb->common);
589}
590
591
592
593
594
595
596static void free_ioctx(struct work_struct *work)
597{
598 struct kioctx *ctx = container_of(to_rcu_work(work), struct kioctx,
599 free_rwork);
600 pr_debug("freeing %p\n", ctx);
601
602 aio_free_ring(ctx);
603 free_percpu(ctx->cpu);
604 percpu_ref_exit(&ctx->reqs);
605 percpu_ref_exit(&ctx->users);
606 kmem_cache_free(kioctx_cachep, ctx);
607}
608
609static void free_ioctx_reqs(struct percpu_ref *ref)
610{
611 struct kioctx *ctx = container_of(ref, struct kioctx, reqs);
612
613
614 if (ctx->rq_wait && atomic_dec_and_test(&ctx->rq_wait->count))
615 complete(&ctx->rq_wait->comp);
616
617
618 INIT_RCU_WORK(&ctx->free_rwork, free_ioctx);
619 queue_rcu_work(system_wq, &ctx->free_rwork);
620}
621
622
623
624
625
626
627static void free_ioctx_users(struct percpu_ref *ref)
628{
629 struct kioctx *ctx = container_of(ref, struct kioctx, users);
630 struct aio_kiocb *req;
631
632 spin_lock_irq(&ctx->ctx_lock);
633
634 while (!list_empty(&ctx->active_reqs)) {
635 req = list_first_entry(&ctx->active_reqs,
636 struct aio_kiocb, ki_list);
637 kiocb_cancel(req);
638 list_del_init(&req->ki_list);
639 }
640
641 spin_unlock_irq(&ctx->ctx_lock);
642
643 percpu_ref_kill(&ctx->reqs);
644 percpu_ref_put(&ctx->reqs);
645}
646
647static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
648{
649 unsigned i, new_nr;
650 struct kioctx_table *table, *old;
651 struct aio_ring *ring;
652
653 spin_lock(&mm->ioctx_lock);
654 table = rcu_dereference_raw(mm->ioctx_table);
655
656 while (1) {
657 if (table)
658 for (i = 0; i < table->nr; i++)
659 if (!rcu_access_pointer(table->table[i])) {
660 ctx->id = i;
661 rcu_assign_pointer(table->table[i], ctx);
662 spin_unlock(&mm->ioctx_lock);
663
664
665
666
667
668 ring = kmap_atomic(ctx->ring_pages[0]);
669 ring->id = ctx->id;
670 kunmap_atomic(ring);
671 return 0;
672 }
673
674 new_nr = (table ? table->nr : 1) * 4;
675 spin_unlock(&mm->ioctx_lock);
676
677 table = kzalloc(sizeof(*table) + sizeof(struct kioctx *) *
678 new_nr, GFP_KERNEL);
679 if (!table)
680 return -ENOMEM;
681
682 table->nr = new_nr;
683
684 spin_lock(&mm->ioctx_lock);
685 old = rcu_dereference_raw(mm->ioctx_table);
686
687 if (!old) {
688 rcu_assign_pointer(mm->ioctx_table, table);
689 } else if (table->nr > old->nr) {
690 memcpy(table->table, old->table,
691 old->nr * sizeof(struct kioctx *));
692
693 rcu_assign_pointer(mm->ioctx_table, table);
694 kfree_rcu(old, rcu);
695 } else {
696 kfree(table);
697 table = old;
698 }
699 }
700}
701
702static void aio_nr_sub(unsigned nr)
703{
704 spin_lock(&aio_nr_lock);
705 if (WARN_ON(aio_nr - nr > aio_nr))
706 aio_nr = 0;
707 else
708 aio_nr -= nr;
709 spin_unlock(&aio_nr_lock);
710}
711
712
713
714
715static struct kioctx *ioctx_alloc(unsigned nr_events)
716{
717 struct mm_struct *mm = current->mm;
718 struct kioctx *ctx;
719 int err = -ENOMEM;
720
721
722
723
724
725 unsigned int max_reqs = nr_events;
726
727
728
729
730
731
732
733
734
735
736 nr_events = max(nr_events, num_possible_cpus() * 4);
737 nr_events *= 2;
738
739
740 if (nr_events > (0x10000000U / sizeof(struct io_event))) {
741 pr_debug("ENOMEM: nr_events too high\n");
742 return ERR_PTR(-EINVAL);
743 }
744
745 if (!nr_events || (unsigned long)max_reqs > aio_max_nr)
746 return ERR_PTR(-EAGAIN);
747
748 ctx = kmem_cache_zalloc(kioctx_cachep, GFP_KERNEL);
749 if (!ctx)
750 return ERR_PTR(-ENOMEM);
751
752 ctx->max_reqs = max_reqs;
753
754 spin_lock_init(&ctx->ctx_lock);
755 spin_lock_init(&ctx->completion_lock);
756 mutex_init(&ctx->ring_lock);
757
758
759 mutex_lock(&ctx->ring_lock);
760 init_waitqueue_head(&ctx->wait);
761
762 INIT_LIST_HEAD(&ctx->active_reqs);
763
764 if (percpu_ref_init(&ctx->users, free_ioctx_users, 0, GFP_KERNEL))
765 goto err;
766
767 if (percpu_ref_init(&ctx->reqs, free_ioctx_reqs, 0, GFP_KERNEL))
768 goto err;
769
770 ctx->cpu = alloc_percpu(struct kioctx_cpu);
771 if (!ctx->cpu)
772 goto err;
773
774 err = aio_setup_ring(ctx, nr_events);
775 if (err < 0)
776 goto err;
777
778 atomic_set(&ctx->reqs_available, ctx->nr_events - 1);
779 ctx->req_batch = (ctx->nr_events - 1) / (num_possible_cpus() * 4);
780 if (ctx->req_batch < 1)
781 ctx->req_batch = 1;
782
783
784 spin_lock(&aio_nr_lock);
785 if (aio_nr + ctx->max_reqs > aio_max_nr ||
786 aio_nr + ctx->max_reqs < aio_nr) {
787 spin_unlock(&aio_nr_lock);
788 err = -EAGAIN;
789 goto err_ctx;
790 }
791 aio_nr += ctx->max_reqs;
792 spin_unlock(&aio_nr_lock);
793
794 percpu_ref_get(&ctx->users);
795 percpu_ref_get(&ctx->reqs);
796
797 err = ioctx_add_table(ctx, mm);
798 if (err)
799 goto err_cleanup;
800
801
802 mutex_unlock(&ctx->ring_lock);
803
804 pr_debug("allocated ioctx %p[%ld]: mm=%p mask=0x%x\n",
805 ctx, ctx->user_id, mm, ctx->nr_events);
806 return ctx;
807
808err_cleanup:
809 aio_nr_sub(ctx->max_reqs);
810err_ctx:
811 atomic_set(&ctx->dead, 1);
812 if (ctx->mmap_size)
813 vm_munmap(ctx->mmap_base, ctx->mmap_size);
814 aio_free_ring(ctx);
815err:
816 mutex_unlock(&ctx->ring_lock);
817 free_percpu(ctx->cpu);
818 percpu_ref_exit(&ctx->reqs);
819 percpu_ref_exit(&ctx->users);
820 kmem_cache_free(kioctx_cachep, ctx);
821 pr_debug("error allocating ioctx %d\n", err);
822 return ERR_PTR(err);
823}
824
825
826
827
828
829
830static int kill_ioctx(struct mm_struct *mm, struct kioctx *ctx,
831 struct ctx_rq_wait *wait)
832{
833 struct kioctx_table *table;
834
835 spin_lock(&mm->ioctx_lock);
836 if (atomic_xchg(&ctx->dead, 1)) {
837 spin_unlock(&mm->ioctx_lock);
838 return -EINVAL;
839 }
840
841 table = rcu_dereference_raw(mm->ioctx_table);
842 WARN_ON(ctx != rcu_access_pointer(table->table[ctx->id]));
843 RCU_INIT_POINTER(table->table[ctx->id], NULL);
844 spin_unlock(&mm->ioctx_lock);
845
846
847 wake_up_all(&ctx->wait);
848
849
850
851
852
853
854
855
856 aio_nr_sub(ctx->max_reqs);
857
858 if (ctx->mmap_size)
859 vm_munmap(ctx->mmap_base, ctx->mmap_size);
860
861 ctx->rq_wait = wait;
862 percpu_ref_kill(&ctx->users);
863 return 0;
864}
865
866
867
868
869
870
871
872
873
874void exit_aio(struct mm_struct *mm)
875{
876 struct kioctx_table *table = rcu_dereference_raw(mm->ioctx_table);
877 struct ctx_rq_wait wait;
878 int i, skipped;
879
880 if (!table)
881 return;
882
883 atomic_set(&wait.count, table->nr);
884 init_completion(&wait.comp);
885
886 skipped = 0;
887 for (i = 0; i < table->nr; ++i) {
888 struct kioctx *ctx =
889 rcu_dereference_protected(table->table[i], true);
890
891 if (!ctx) {
892 skipped++;
893 continue;
894 }
895
896
897
898
899
900
901
902
903 ctx->mmap_size = 0;
904 kill_ioctx(mm, ctx, &wait);
905 }
906
907 if (!atomic_sub_and_test(skipped, &wait.count)) {
908
909 wait_for_completion(&wait.comp);
910 }
911
912 RCU_INIT_POINTER(mm->ioctx_table, NULL);
913 kfree(table);
914}
915
916static void put_reqs_available(struct kioctx *ctx, unsigned nr)
917{
918 struct kioctx_cpu *kcpu;
919 unsigned long flags;
920
921 local_irq_save(flags);
922 kcpu = this_cpu_ptr(ctx->cpu);
923 kcpu->reqs_available += nr;
924
925 while (kcpu->reqs_available >= ctx->req_batch * 2) {
926 kcpu->reqs_available -= ctx->req_batch;
927 atomic_add(ctx->req_batch, &ctx->reqs_available);
928 }
929
930 local_irq_restore(flags);
931}
932
933static bool get_reqs_available(struct kioctx *ctx)
934{
935 struct kioctx_cpu *kcpu;
936 bool ret = false;
937 unsigned long flags;
938
939 local_irq_save(flags);
940 kcpu = this_cpu_ptr(ctx->cpu);
941 if (!kcpu->reqs_available) {
942 int old, avail = atomic_read(&ctx->reqs_available);
943
944 do {
945 if (avail < ctx->req_batch)
946 goto out;
947
948 old = avail;
949 avail = atomic_cmpxchg(&ctx->reqs_available,
950 avail, avail - ctx->req_batch);
951 } while (avail != old);
952
953 kcpu->reqs_available += ctx->req_batch;
954 }
955
956 ret = true;
957 kcpu->reqs_available--;
958out:
959 local_irq_restore(flags);
960 return ret;
961}
962
963
964
965
966
967
968
969
970static void refill_reqs_available(struct kioctx *ctx, unsigned head,
971 unsigned tail)
972{
973 unsigned events_in_ring, completed;
974
975
976 head %= ctx->nr_events;
977 if (head <= tail)
978 events_in_ring = tail - head;
979 else
980 events_in_ring = ctx->nr_events - (head - tail);
981
982 completed = ctx->completed_events;
983 if (events_in_ring < completed)
984 completed -= events_in_ring;
985 else
986 completed = 0;
987
988 if (!completed)
989 return;
990
991 ctx->completed_events -= completed;
992 put_reqs_available(ctx, completed);
993}
994
995
996
997
998
999static void user_refill_reqs_available(struct kioctx *ctx)
1000{
1001 spin_lock_irq(&ctx->completion_lock);
1002 if (ctx->completed_events) {
1003 struct aio_ring *ring;
1004 unsigned head;
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015 ring = kmap_atomic(ctx->ring_pages[0]);
1016 head = ring->head;
1017 kunmap_atomic(ring);
1018
1019 refill_reqs_available(ctx, head, ctx->tail);
1020 }
1021
1022 spin_unlock_irq(&ctx->completion_lock);
1023}
1024
1025
1026
1027
1028
1029static inline struct aio_kiocb *aio_get_req(struct kioctx *ctx)
1030{
1031 struct aio_kiocb *req;
1032
1033 if (!get_reqs_available(ctx)) {
1034 user_refill_reqs_available(ctx);
1035 if (!get_reqs_available(ctx))
1036 return NULL;
1037 }
1038
1039 req = kmem_cache_alloc(kiocb_cachep, GFP_KERNEL|__GFP_ZERO);
1040 if (unlikely(!req))
1041 goto out_put;
1042
1043 percpu_ref_get(&ctx->reqs);
1044
1045 req->ki_ctx = ctx;
1046 return req;
1047out_put:
1048 put_reqs_available(ctx, 1);
1049 return NULL;
1050}
1051
1052static void kiocb_free(struct aio_kiocb *req)
1053{
1054 if (req->common.ki_filp)
1055 fput(req->common.ki_filp);
1056 if (req->ki_eventfd != NULL)
1057 eventfd_ctx_put(req->ki_eventfd);
1058 kmem_cache_free(kiocb_cachep, req);
1059}
1060
1061static struct kioctx *lookup_ioctx(unsigned long ctx_id)
1062{
1063 struct aio_ring __user *ring = (void __user *)ctx_id;
1064 struct mm_struct *mm = current->mm;
1065 struct kioctx *ctx, *ret = NULL;
1066 struct kioctx_table *table;
1067 unsigned id;
1068
1069 if (get_user(id, &ring->id))
1070 return NULL;
1071
1072 rcu_read_lock();
1073 table = rcu_dereference(mm->ioctx_table);
1074
1075 if (!table || id >= table->nr)
1076 goto out;
1077
1078 ctx = rcu_dereference(table->table[id]);
1079 if (ctx && ctx->user_id == ctx_id) {
1080 if (percpu_ref_tryget_live(&ctx->users))
1081 ret = ctx;
1082 }
1083out:
1084 rcu_read_unlock();
1085 return ret;
1086}
1087
1088
1089
1090
1091static void aio_complete(struct kiocb *kiocb, long res, long res2)
1092{
1093 struct aio_kiocb *iocb = container_of(kiocb, struct aio_kiocb, common);
1094 struct kioctx *ctx = iocb->ki_ctx;
1095 struct aio_ring *ring;
1096 struct io_event *ev_page, *event;
1097 unsigned tail, pos, head;
1098 unsigned long flags;
1099
1100 if (kiocb->ki_flags & IOCB_WRITE) {
1101 struct file *file = kiocb->ki_filp;
1102
1103
1104
1105
1106
1107 if (S_ISREG(file_inode(file)->i_mode))
1108 __sb_writers_acquired(file_inode(file)->i_sb, SB_FREEZE_WRITE);
1109 file_end_write(file);
1110 }
1111
1112
1113
1114
1115
1116
1117
1118
1119 BUG_ON(is_sync_kiocb(kiocb));
1120
1121 if (iocb->ki_list.next) {
1122 unsigned long flags;
1123
1124 spin_lock_irqsave(&ctx->ctx_lock, flags);
1125 list_del(&iocb->ki_list);
1126 spin_unlock_irqrestore(&ctx->ctx_lock, flags);
1127 }
1128
1129
1130
1131
1132
1133
1134 spin_lock_irqsave(&ctx->completion_lock, flags);
1135
1136 tail = ctx->tail;
1137 pos = tail + AIO_EVENTS_OFFSET;
1138
1139 if (++tail >= ctx->nr_events)
1140 tail = 0;
1141
1142 ev_page = kmap_atomic(ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]);
1143 event = ev_page + pos % AIO_EVENTS_PER_PAGE;
1144
1145 event->obj = (u64)(unsigned long)iocb->ki_user_iocb;
1146 event->data = iocb->ki_user_data;
1147 event->res = res;
1148 event->res2 = res2;
1149
1150 kunmap_atomic(ev_page);
1151 flush_dcache_page(ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]);
1152
1153 pr_debug("%p[%u]: %p: %p %Lx %lx %lx\n",
1154 ctx, tail, iocb, iocb->ki_user_iocb, iocb->ki_user_data,
1155 res, res2);
1156
1157
1158
1159
1160 smp_wmb();
1161
1162 ctx->tail = tail;
1163
1164 ring = kmap_atomic(ctx->ring_pages[0]);
1165 head = ring->head;
1166 ring->tail = tail;
1167 kunmap_atomic(ring);
1168 flush_dcache_page(ctx->ring_pages[0]);
1169
1170 ctx->completed_events++;
1171 if (ctx->completed_events > 1)
1172 refill_reqs_available(ctx, head, tail);
1173 spin_unlock_irqrestore(&ctx->completion_lock, flags);
1174
1175 pr_debug("added to ring %p at [%u]\n", iocb, tail);
1176
1177
1178
1179
1180
1181
1182 if (iocb->ki_eventfd != NULL)
1183 eventfd_signal(iocb->ki_eventfd, 1);
1184
1185
1186 kiocb_free(iocb);
1187
1188
1189
1190
1191
1192
1193
1194 smp_mb();
1195
1196 if (waitqueue_active(&ctx->wait))
1197 wake_up(&ctx->wait);
1198
1199 percpu_ref_put(&ctx->reqs);
1200}
1201
1202
1203
1204
1205
1206static long aio_read_events_ring(struct kioctx *ctx,
1207 struct io_event __user *event, long nr)
1208{
1209 struct aio_ring *ring;
1210 unsigned head, tail, pos;
1211 long ret = 0;
1212 int copy_ret;
1213
1214
1215
1216
1217
1218
1219
1220 sched_annotate_sleep();
1221 mutex_lock(&ctx->ring_lock);
1222
1223
1224 ring = kmap_atomic(ctx->ring_pages[0]);
1225 head = ring->head;
1226 tail = ring->tail;
1227 kunmap_atomic(ring);
1228
1229
1230
1231
1232
1233 smp_rmb();
1234
1235 pr_debug("h%u t%u m%u\n", head, tail, ctx->nr_events);
1236
1237 if (head == tail)
1238 goto out;
1239
1240 head %= ctx->nr_events;
1241 tail %= ctx->nr_events;
1242
1243 while (ret < nr) {
1244 long avail;
1245 struct io_event *ev;
1246 struct page *page;
1247
1248 avail = (head <= tail ? tail : ctx->nr_events) - head;
1249 if (head == tail)
1250 break;
1251
1252 avail = min(avail, nr - ret);
1253 avail = min_t(long, avail, AIO_EVENTS_PER_PAGE -
1254 ((head + AIO_EVENTS_OFFSET) % AIO_EVENTS_PER_PAGE));
1255
1256 pos = head + AIO_EVENTS_OFFSET;
1257 page = ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE];
1258 pos %= AIO_EVENTS_PER_PAGE;
1259
1260 ev = kmap(page);
1261 copy_ret = copy_to_user(event + ret, ev + pos,
1262 sizeof(*ev) * avail);
1263 kunmap(page);
1264
1265 if (unlikely(copy_ret)) {
1266 ret = -EFAULT;
1267 goto out;
1268 }
1269
1270 ret += avail;
1271 head += avail;
1272 head %= ctx->nr_events;
1273 }
1274
1275 ring = kmap_atomic(ctx->ring_pages[0]);
1276 ring->head = head;
1277 kunmap_atomic(ring);
1278 flush_dcache_page(ctx->ring_pages[0]);
1279
1280 pr_debug("%li h%u t%u\n", ret, head, tail);
1281out:
1282 mutex_unlock(&ctx->ring_lock);
1283
1284 return ret;
1285}
1286
1287static bool aio_read_events(struct kioctx *ctx, long min_nr, long nr,
1288 struct io_event __user *event, long *i)
1289{
1290 long ret = aio_read_events_ring(ctx, event + *i, nr - *i);
1291
1292 if (ret > 0)
1293 *i += ret;
1294
1295 if (unlikely(atomic_read(&ctx->dead)))
1296 ret = -EINVAL;
1297
1298 if (!*i)
1299 *i = ret;
1300
1301 return ret < 0 || *i >= min_nr;
1302}
1303
1304static long read_events(struct kioctx *ctx, long min_nr, long nr,
1305 struct io_event __user *event,
1306 ktime_t until)
1307{
1308 long ret = 0;
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324 if (until == 0)
1325 aio_read_events(ctx, min_nr, nr, event, &ret);
1326 else
1327 wait_event_interruptible_hrtimeout(ctx->wait,
1328 aio_read_events(ctx, min_nr, nr, event, &ret),
1329 until);
1330
1331 if (!ret && signal_pending(current))
1332 ret = -EINTR;
1333
1334 return ret;
1335}
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350SYSCALL_DEFINE2(io_setup, unsigned, nr_events, aio_context_t __user *, ctxp)
1351{
1352 struct kioctx *ioctx = NULL;
1353 unsigned long ctx;
1354 long ret;
1355
1356 ret = get_user(ctx, ctxp);
1357 if (unlikely(ret))
1358 goto out;
1359
1360 ret = -EINVAL;
1361 if (unlikely(ctx || nr_events == 0)) {
1362 pr_debug("EINVAL: ctx %lu nr_events %u\n",
1363 ctx, nr_events);
1364 goto out;
1365 }
1366
1367 ioctx = ioctx_alloc(nr_events);
1368 ret = PTR_ERR(ioctx);
1369 if (!IS_ERR(ioctx)) {
1370 ret = put_user(ioctx->user_id, ctxp);
1371 if (ret)
1372 kill_ioctx(current->mm, ioctx, NULL);
1373 percpu_ref_put(&ioctx->users);
1374 }
1375
1376out:
1377 return ret;
1378}
1379
1380#ifdef CONFIG_COMPAT
1381COMPAT_SYSCALL_DEFINE2(io_setup, unsigned, nr_events, u32 __user *, ctx32p)
1382{
1383 struct kioctx *ioctx = NULL;
1384 unsigned long ctx;
1385 long ret;
1386
1387 ret = get_user(ctx, ctx32p);
1388 if (unlikely(ret))
1389 goto out;
1390
1391 ret = -EINVAL;
1392 if (unlikely(ctx || nr_events == 0)) {
1393 pr_debug("EINVAL: ctx %lu nr_events %u\n",
1394 ctx, nr_events);
1395 goto out;
1396 }
1397
1398 ioctx = ioctx_alloc(nr_events);
1399 ret = PTR_ERR(ioctx);
1400 if (!IS_ERR(ioctx)) {
1401
1402 ret = put_user((u32)ioctx->user_id, ctx32p);
1403 if (ret)
1404 kill_ioctx(current->mm, ioctx, NULL);
1405 percpu_ref_put(&ioctx->users);
1406 }
1407
1408out:
1409 return ret;
1410}
1411#endif
1412
1413
1414
1415
1416
1417
1418
1419SYSCALL_DEFINE1(io_destroy, aio_context_t, ctx)
1420{
1421 struct kioctx *ioctx = lookup_ioctx(ctx);
1422 if (likely(NULL != ioctx)) {
1423 struct ctx_rq_wait wait;
1424 int ret;
1425
1426 init_completion(&wait.comp);
1427 atomic_set(&wait.count, 1);
1428
1429
1430
1431
1432
1433 ret = kill_ioctx(current->mm, ioctx, &wait);
1434 percpu_ref_put(&ioctx->users);
1435
1436
1437
1438
1439
1440 if (!ret)
1441 wait_for_completion(&wait.comp);
1442
1443 return ret;
1444 }
1445 pr_debug("EINVAL: invalid context id\n");
1446 return -EINVAL;
1447}
1448
1449static int aio_setup_rw(int rw, struct iocb *iocb, struct iovec **iovec,
1450 bool vectored, bool compat, struct iov_iter *iter)
1451{
1452 void __user *buf = (void __user *)(uintptr_t)iocb->aio_buf;
1453 size_t len = iocb->aio_nbytes;
1454
1455 if (!vectored) {
1456 ssize_t ret = import_single_range(rw, buf, len, *iovec, iter);
1457 *iovec = NULL;
1458 return ret;
1459 }
1460#ifdef CONFIG_COMPAT
1461 if (compat)
1462 return compat_import_iovec(rw, buf, len, UIO_FASTIOV, iovec,
1463 iter);
1464#endif
1465 return import_iovec(rw, buf, len, UIO_FASTIOV, iovec, iter);
1466}
1467
1468static inline ssize_t aio_ret(struct kiocb *req, ssize_t ret)
1469{
1470 switch (ret) {
1471 case -EIOCBQUEUED:
1472 return ret;
1473 case -ERESTARTSYS:
1474 case -ERESTARTNOINTR:
1475 case -ERESTARTNOHAND:
1476 case -ERESTART_RESTARTBLOCK:
1477
1478
1479
1480
1481 ret = -EINTR;
1482
1483 default:
1484 aio_complete(req, ret, 0);
1485 return 0;
1486 }
1487}
1488
1489static ssize_t aio_read(struct kiocb *req, struct iocb *iocb, bool vectored,
1490 bool compat)
1491{
1492 struct file *file = req->ki_filp;
1493 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
1494 struct iov_iter iter;
1495 ssize_t ret;
1496
1497 if (unlikely(!(file->f_mode & FMODE_READ)))
1498 return -EBADF;
1499 if (unlikely(!file->f_op->read_iter))
1500 return -EINVAL;
1501
1502 ret = aio_setup_rw(READ, iocb, &iovec, vectored, compat, &iter);
1503 if (ret)
1504 return ret;
1505 ret = rw_verify_area(READ, file, &req->ki_pos, iov_iter_count(&iter));
1506 if (!ret)
1507 ret = aio_ret(req, call_read_iter(file, req, &iter));
1508 kfree(iovec);
1509 return ret;
1510}
1511
1512static ssize_t aio_write(struct kiocb *req, struct iocb *iocb, bool vectored,
1513 bool compat)
1514{
1515 struct file *file = req->ki_filp;
1516 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
1517 struct iov_iter iter;
1518 ssize_t ret;
1519
1520 if (unlikely(!(file->f_mode & FMODE_WRITE)))
1521 return -EBADF;
1522 if (unlikely(!file->f_op->write_iter))
1523 return -EINVAL;
1524
1525 ret = aio_setup_rw(WRITE, iocb, &iovec, vectored, compat, &iter);
1526 if (ret)
1527 return ret;
1528 ret = rw_verify_area(WRITE, file, &req->ki_pos, iov_iter_count(&iter));
1529 if (!ret) {
1530 req->ki_flags |= IOCB_WRITE;
1531 file_start_write(file);
1532 ret = aio_ret(req, call_write_iter(file, req, &iter));
1533
1534
1535
1536
1537
1538 if (S_ISREG(file_inode(file)->i_mode))
1539 __sb_writers_release(file_inode(file)->i_sb, SB_FREEZE_WRITE);
1540 }
1541 kfree(iovec);
1542 return ret;
1543}
1544
1545static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
1546 struct iocb *iocb, bool compat)
1547{
1548 struct aio_kiocb *req;
1549 struct file *file;
1550 ssize_t ret;
1551
1552
1553 if (unlikely(iocb->aio_reserved2)) {
1554 pr_debug("EINVAL: reserve field set\n");
1555 return -EINVAL;
1556 }
1557
1558
1559 if (unlikely(
1560 (iocb->aio_buf != (unsigned long)iocb->aio_buf) ||
1561 (iocb->aio_nbytes != (size_t)iocb->aio_nbytes) ||
1562 ((ssize_t)iocb->aio_nbytes < 0)
1563 )) {
1564 pr_debug("EINVAL: overflow check\n");
1565 return -EINVAL;
1566 }
1567
1568 req = aio_get_req(ctx);
1569 if (unlikely(!req))
1570 return -EAGAIN;
1571
1572 req->common.ki_filp = file = fget(iocb->aio_fildes);
1573 if (unlikely(!req->common.ki_filp)) {
1574 ret = -EBADF;
1575 goto out_put_req;
1576 }
1577 req->common.ki_pos = iocb->aio_offset;
1578 req->common.ki_complete = aio_complete;
1579 req->common.ki_flags = iocb_flags(req->common.ki_filp);
1580 req->common.ki_hint = file_write_hint(file);
1581
1582 if (iocb->aio_flags & IOCB_FLAG_RESFD) {
1583
1584
1585
1586
1587
1588
1589 req->ki_eventfd = eventfd_ctx_fdget((int) iocb->aio_resfd);
1590 if (IS_ERR(req->ki_eventfd)) {
1591 ret = PTR_ERR(req->ki_eventfd);
1592 req->ki_eventfd = NULL;
1593 goto out_put_req;
1594 }
1595
1596 req->common.ki_flags |= IOCB_EVENTFD;
1597 }
1598
1599 ret = kiocb_set_rw_flags(&req->common, iocb->aio_rw_flags);
1600 if (unlikely(ret)) {
1601 pr_debug("EINVAL: aio_rw_flags\n");
1602 goto out_put_req;
1603 }
1604
1605 ret = put_user(KIOCB_KEY, &user_iocb->aio_key);
1606 if (unlikely(ret)) {
1607 pr_debug("EFAULT: aio_key\n");
1608 goto out_put_req;
1609 }
1610
1611 req->ki_user_iocb = user_iocb;
1612 req->ki_user_data = iocb->aio_data;
1613
1614 get_file(file);
1615 switch (iocb->aio_lio_opcode) {
1616 case IOCB_CMD_PREAD:
1617 ret = aio_read(&req->common, iocb, false, compat);
1618 break;
1619 case IOCB_CMD_PWRITE:
1620 ret = aio_write(&req->common, iocb, false, compat);
1621 break;
1622 case IOCB_CMD_PREADV:
1623 ret = aio_read(&req->common, iocb, true, compat);
1624 break;
1625 case IOCB_CMD_PWRITEV:
1626 ret = aio_write(&req->common, iocb, true, compat);
1627 break;
1628 default:
1629 pr_debug("invalid aio operation %d\n", iocb->aio_lio_opcode);
1630 ret = -EINVAL;
1631 break;
1632 }
1633 fput(file);
1634
1635 if (ret && ret != -EIOCBQUEUED)
1636 goto out_put_req;
1637 return 0;
1638out_put_req:
1639 put_reqs_available(ctx, 1);
1640 percpu_ref_put(&ctx->reqs);
1641 kiocb_free(req);
1642 return ret;
1643}
1644
1645static long do_io_submit(aio_context_t ctx_id, long nr,
1646 struct iocb __user *__user *iocbpp, bool compat)
1647{
1648 struct kioctx *ctx;
1649 long ret = 0;
1650 int i = 0;
1651 struct blk_plug plug;
1652
1653 if (unlikely(nr < 0))
1654 return -EINVAL;
1655
1656 if (unlikely(nr > LONG_MAX/sizeof(*iocbpp)))
1657 nr = LONG_MAX/sizeof(*iocbpp);
1658
1659 if (unlikely(!access_ok(VERIFY_READ, iocbpp, (nr*sizeof(*iocbpp)))))
1660 return -EFAULT;
1661
1662 ctx = lookup_ioctx(ctx_id);
1663 if (unlikely(!ctx)) {
1664 pr_debug("EINVAL: invalid context id\n");
1665 return -EINVAL;
1666 }
1667
1668 blk_start_plug(&plug);
1669
1670
1671
1672
1673
1674 for (i=0; i<nr; i++) {
1675 struct iocb __user *user_iocb;
1676 struct iocb tmp;
1677
1678 if (unlikely(__get_user(user_iocb, iocbpp + i))) {
1679 ret = -EFAULT;
1680 break;
1681 }
1682
1683 if (unlikely(copy_from_user(&tmp, user_iocb, sizeof(tmp)))) {
1684 ret = -EFAULT;
1685 break;
1686 }
1687
1688 ret = io_submit_one(ctx, user_iocb, &tmp, compat);
1689 if (ret)
1690 break;
1691 }
1692 blk_finish_plug(&plug);
1693
1694 percpu_ref_put(&ctx->users);
1695 return i ? i : ret;
1696}
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710SYSCALL_DEFINE3(io_submit, aio_context_t, ctx_id, long, nr,
1711 struct iocb __user * __user *, iocbpp)
1712{
1713 return do_io_submit(ctx_id, nr, iocbpp, 0);
1714}
1715
1716#ifdef CONFIG_COMPAT
1717static inline long
1718copy_iocb(long nr, u32 __user *ptr32, struct iocb __user * __user *ptr64)
1719{
1720 compat_uptr_t uptr;
1721 int i;
1722
1723 for (i = 0; i < nr; ++i) {
1724 if (get_user(uptr, ptr32 + i))
1725 return -EFAULT;
1726 if (put_user(compat_ptr(uptr), ptr64 + i))
1727 return -EFAULT;
1728 }
1729 return 0;
1730}
1731
1732#define MAX_AIO_SUBMITS (PAGE_SIZE/sizeof(struct iocb *))
1733
1734COMPAT_SYSCALL_DEFINE3(io_submit, compat_aio_context_t, ctx_id,
1735 int, nr, u32 __user *, iocb)
1736{
1737 struct iocb __user * __user *iocb64;
1738 long ret;
1739
1740 if (unlikely(nr < 0))
1741 return -EINVAL;
1742
1743 if (nr > MAX_AIO_SUBMITS)
1744 nr = MAX_AIO_SUBMITS;
1745
1746 iocb64 = compat_alloc_user_space(nr * sizeof(*iocb64));
1747 ret = copy_iocb(nr, iocb, iocb64);
1748 if (!ret)
1749 ret = do_io_submit(ctx_id, nr, iocb64, 1);
1750 return ret;
1751}
1752#endif
1753
1754
1755
1756
1757static struct aio_kiocb *
1758lookup_kiocb(struct kioctx *ctx, struct iocb __user *iocb, u32 key)
1759{
1760 struct aio_kiocb *kiocb;
1761
1762 assert_spin_locked(&ctx->ctx_lock);
1763
1764 if (key != KIOCB_KEY)
1765 return NULL;
1766
1767
1768 list_for_each_entry(kiocb, &ctx->active_reqs, ki_list) {
1769 if (kiocb->ki_user_iocb == iocb)
1770 return kiocb;
1771 }
1772 return NULL;
1773}
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb,
1786 struct io_event __user *, result)
1787{
1788 struct kioctx *ctx;
1789 struct aio_kiocb *kiocb;
1790 u32 key;
1791 int ret;
1792
1793 ret = get_user(key, &iocb->aio_key);
1794 if (unlikely(ret))
1795 return -EFAULT;
1796
1797 ctx = lookup_ioctx(ctx_id);
1798 if (unlikely(!ctx))
1799 return -EINVAL;
1800
1801 spin_lock_irq(&ctx->ctx_lock);
1802
1803 kiocb = lookup_kiocb(ctx, iocb, key);
1804 if (kiocb)
1805 ret = kiocb_cancel(kiocb);
1806 else
1807 ret = -EINVAL;
1808
1809 spin_unlock_irq(&ctx->ctx_lock);
1810
1811 if (!ret) {
1812
1813
1814
1815
1816
1817 ret = -EINPROGRESS;
1818 }
1819
1820 percpu_ref_put(&ctx->users);
1821
1822 return ret;
1823}
1824
1825static long do_io_getevents(aio_context_t ctx_id,
1826 long min_nr,
1827 long nr,
1828 struct io_event __user *events,
1829 struct timespec64 *ts)
1830{
1831 ktime_t until = ts ? timespec64_to_ktime(*ts) : KTIME_MAX;
1832 struct kioctx *ioctx = lookup_ioctx(ctx_id);
1833 long ret = -EINVAL;
1834
1835 if (likely(ioctx)) {
1836 if (likely(min_nr <= nr && min_nr >= 0))
1837 ret = read_events(ioctx, min_nr, nr, events, until);
1838 percpu_ref_put(&ioctx->users);
1839 }
1840
1841 return ret;
1842}
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856SYSCALL_DEFINE5(io_getevents, aio_context_t, ctx_id,
1857 long, min_nr,
1858 long, nr,
1859 struct io_event __user *, events,
1860 struct timespec __user *, timeout)
1861{
1862 struct timespec64 ts;
1863
1864 if (timeout) {
1865 if (unlikely(get_timespec64(&ts, timeout)))
1866 return -EFAULT;
1867 }
1868
1869 return do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL);
1870}
1871
1872#ifdef CONFIG_COMPAT
1873COMPAT_SYSCALL_DEFINE5(io_getevents, compat_aio_context_t, ctx_id,
1874 compat_long_t, min_nr,
1875 compat_long_t, nr,
1876 struct io_event __user *, events,
1877 struct compat_timespec __user *, timeout)
1878{
1879 struct timespec64 t;
1880
1881 if (timeout) {
1882 if (compat_get_timespec64(&t, timeout))
1883 return -EFAULT;
1884
1885 }
1886
1887 return do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL);
1888}
1889#endif
1890