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11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/errno.h>
14#include <linux/time.h>
15#include <linux/aio_abi.h>
16#include <linux/export.h>
17#include <linux/syscalls.h>
18#include <linux/backing-dev.h>
19#include <linux/uio.h>
20
21#define DEBUG 0
22
23#include <linux/sched.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/slab.h>
30#include <linux/timer.h>
31#include <linux/aio.h>
32#include <linux/highmem.h>
33#include <linux/workqueue.h>
34#include <linux/security.h>
35#include <linux/eventfd.h>
36#include <linux/blkdev.h>
37#include <linux/compat.h>
38
39#include <asm/kmap_types.h>
40#include <asm/uaccess.h>
41
42#if DEBUG > 1
43#define dprintk printk
44#else
45#define dprintk(x...) do { ; } while (0)
46#endif
47
48
49static DEFINE_SPINLOCK(aio_nr_lock);
50unsigned long aio_nr;
51unsigned long aio_max_nr = 0x10000;
52
53
54static struct kmem_cache *kiocb_cachep;
55static struct kmem_cache *kioctx_cachep;
56
57static struct workqueue_struct *aio_wq;
58
59static void aio_kick_handler(struct work_struct *);
60static void aio_queue_work(struct kioctx *);
61
62
63
64
65
66static int __init aio_setup(void)
67{
68 kiocb_cachep = KMEM_CACHE(kiocb, SLAB_HWCACHE_ALIGN|SLAB_PANIC);
69 kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC);
70
71 aio_wq = alloc_workqueue("aio", 0, 1);
72 BUG_ON(!aio_wq);
73
74 pr_debug("aio_setup: sizeof(struct page) = %d\n", (int)sizeof(struct page));
75
76 return 0;
77}
78__initcall(aio_setup);
79
80static void aio_free_ring(struct kioctx *ctx)
81{
82 struct aio_ring_info *info = &ctx->ring_info;
83 long i;
84
85 for (i=0; i<info->nr_pages; i++)
86 put_page(info->ring_pages[i]);
87
88 if (info->mmap_size) {
89 BUG_ON(ctx->mm != current->mm);
90 vm_munmap(info->mmap_base, info->mmap_size);
91 }
92
93 if (info->ring_pages && info->ring_pages != info->internal_pages)
94 kfree(info->ring_pages);
95 info->ring_pages = NULL;
96 info->nr = 0;
97}
98
99static int aio_setup_ring(struct kioctx *ctx)
100{
101 struct aio_ring *ring;
102 struct aio_ring_info *info = &ctx->ring_info;
103 unsigned nr_events = ctx->max_reqs;
104 unsigned long size, populate;
105 int nr_pages;
106
107
108 nr_events += 2;
109
110 size = sizeof(struct aio_ring);
111 size += sizeof(struct io_event) * nr_events;
112 nr_pages = (size + PAGE_SIZE-1) >> PAGE_SHIFT;
113
114 if (nr_pages < 0)
115 return -EINVAL;
116
117 nr_events = (PAGE_SIZE * nr_pages - sizeof(struct aio_ring)) / sizeof(struct io_event);
118
119 info->nr = 0;
120 info->ring_pages = info->internal_pages;
121 if (nr_pages > AIO_RING_PAGES) {
122 info->ring_pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
123 if (!info->ring_pages)
124 return -ENOMEM;
125 }
126
127 info->mmap_size = nr_pages * PAGE_SIZE;
128 dprintk("attempting mmap of %lu bytes\n", info->mmap_size);
129 down_write(&ctx->mm->mmap_sem);
130 info->mmap_base = do_mmap_pgoff(NULL, 0, info->mmap_size,
131 PROT_READ|PROT_WRITE,
132 MAP_ANONYMOUS|MAP_PRIVATE, 0,
133 &populate);
134 if (IS_ERR((void *)info->mmap_base)) {
135 up_write(&ctx->mm->mmap_sem);
136 info->mmap_size = 0;
137 aio_free_ring(ctx);
138 return -EAGAIN;
139 }
140
141 dprintk("mmap address: 0x%08lx\n", info->mmap_base);
142 info->nr_pages = get_user_pages(current, ctx->mm,
143 info->mmap_base, nr_pages,
144 1, 0, info->ring_pages, NULL);
145 up_write(&ctx->mm->mmap_sem);
146
147 if (unlikely(info->nr_pages != nr_pages)) {
148 aio_free_ring(ctx);
149 return -EAGAIN;
150 }
151 if (populate)
152 mm_populate(info->mmap_base, populate);
153
154 ctx->user_id = info->mmap_base;
155
156 info->nr = nr_events;
157
158 ring = kmap_atomic(info->ring_pages[0]);
159 ring->nr = nr_events;
160 ring->id = ctx->user_id;
161 ring->head = ring->tail = 0;
162 ring->magic = AIO_RING_MAGIC;
163 ring->compat_features = AIO_RING_COMPAT_FEATURES;
164 ring->incompat_features = AIO_RING_INCOMPAT_FEATURES;
165 ring->header_length = sizeof(struct aio_ring);
166 kunmap_atomic(ring);
167
168 return 0;
169}
170
171
172
173
174
175#define AIO_EVENTS_PER_PAGE (PAGE_SIZE / sizeof(struct io_event))
176#define AIO_EVENTS_FIRST_PAGE ((PAGE_SIZE - sizeof(struct aio_ring)) / sizeof(struct io_event))
177#define AIO_EVENTS_OFFSET (AIO_EVENTS_PER_PAGE - AIO_EVENTS_FIRST_PAGE)
178
179#define aio_ring_event(info, nr) ({ \
180 unsigned pos = (nr) + AIO_EVENTS_OFFSET; \
181 struct io_event *__event; \
182 __event = kmap_atomic( \
183 (info)->ring_pages[pos / AIO_EVENTS_PER_PAGE]); \
184 __event += pos % AIO_EVENTS_PER_PAGE; \
185 __event; \
186})
187
188#define put_aio_ring_event(event) do { \
189 struct io_event *__event = (event); \
190 (void)__event; \
191 kunmap_atomic((void *)((unsigned long)__event & PAGE_MASK)); \
192} while(0)
193
194static void ctx_rcu_free(struct rcu_head *head)
195{
196 struct kioctx *ctx = container_of(head, struct kioctx, rcu_head);
197 kmem_cache_free(kioctx_cachep, ctx);
198}
199
200
201
202
203
204static void __put_ioctx(struct kioctx *ctx)
205{
206 unsigned nr_events = ctx->max_reqs;
207 BUG_ON(ctx->reqs_active);
208
209 cancel_delayed_work_sync(&ctx->wq);
210 aio_free_ring(ctx);
211 mmdrop(ctx->mm);
212 ctx->mm = NULL;
213 if (nr_events) {
214 spin_lock(&aio_nr_lock);
215 BUG_ON(aio_nr - nr_events > aio_nr);
216 aio_nr -= nr_events;
217 spin_unlock(&aio_nr_lock);
218 }
219 pr_debug("__put_ioctx: freeing %p\n", ctx);
220 call_rcu(&ctx->rcu_head, ctx_rcu_free);
221}
222
223static inline int try_get_ioctx(struct kioctx *kioctx)
224{
225 return atomic_inc_not_zero(&kioctx->users);
226}
227
228static inline void put_ioctx(struct kioctx *kioctx)
229{
230 BUG_ON(atomic_read(&kioctx->users) <= 0);
231 if (unlikely(atomic_dec_and_test(&kioctx->users)))
232 __put_ioctx(kioctx);
233}
234
235
236
237
238static struct kioctx *ioctx_alloc(unsigned nr_events)
239{
240 struct mm_struct *mm;
241 struct kioctx *ctx;
242 int err = -ENOMEM;
243
244
245 if ((nr_events > (0x10000000U / sizeof(struct io_event))) ||
246 (nr_events > (0x10000000U / sizeof(struct kiocb)))) {
247 pr_debug("ENOMEM: nr_events too high\n");
248 return ERR_PTR(-EINVAL);
249 }
250
251 if (!nr_events || (unsigned long)nr_events > aio_max_nr)
252 return ERR_PTR(-EAGAIN);
253
254 ctx = kmem_cache_zalloc(kioctx_cachep, GFP_KERNEL);
255 if (!ctx)
256 return ERR_PTR(-ENOMEM);
257
258 ctx->max_reqs = nr_events;
259 mm = ctx->mm = current->mm;
260 atomic_inc(&mm->mm_count);
261
262 atomic_set(&ctx->users, 2);
263 spin_lock_init(&ctx->ctx_lock);
264 spin_lock_init(&ctx->ring_info.ring_lock);
265 init_waitqueue_head(&ctx->wait);
266
267 INIT_LIST_HEAD(&ctx->active_reqs);
268 INIT_LIST_HEAD(&ctx->run_list);
269 INIT_DELAYED_WORK(&ctx->wq, aio_kick_handler);
270
271 if (aio_setup_ring(ctx) < 0)
272 goto out_freectx;
273
274
275 spin_lock(&aio_nr_lock);
276 if (aio_nr + nr_events > aio_max_nr ||
277 aio_nr + nr_events < aio_nr) {
278 spin_unlock(&aio_nr_lock);
279 goto out_cleanup;
280 }
281 aio_nr += ctx->max_reqs;
282 spin_unlock(&aio_nr_lock);
283
284
285 spin_lock(&mm->ioctx_lock);
286 hlist_add_head_rcu(&ctx->list, &mm->ioctx_list);
287 spin_unlock(&mm->ioctx_lock);
288
289 dprintk("aio: allocated ioctx %p[%ld]: mm=%p mask=0x%x\n",
290 ctx, ctx->user_id, current->mm, ctx->ring_info.nr);
291 return ctx;
292
293out_cleanup:
294 err = -EAGAIN;
295 aio_free_ring(ctx);
296out_freectx:
297 mmdrop(mm);
298 kmem_cache_free(kioctx_cachep, ctx);
299 dprintk("aio: error allocating ioctx %d\n", err);
300 return ERR_PTR(err);
301}
302
303
304
305
306
307
308static void kill_ctx(struct kioctx *ctx)
309{
310 int (*cancel)(struct kiocb *, struct io_event *);
311 struct task_struct *tsk = current;
312 DECLARE_WAITQUEUE(wait, tsk);
313 struct io_event res;
314
315 spin_lock_irq(&ctx->ctx_lock);
316 ctx->dead = 1;
317 while (!list_empty(&ctx->active_reqs)) {
318 struct list_head *pos = ctx->active_reqs.next;
319 struct kiocb *iocb = list_kiocb(pos);
320 list_del_init(&iocb->ki_list);
321 cancel = iocb->ki_cancel;
322 kiocbSetCancelled(iocb);
323 if (cancel) {
324 iocb->ki_users++;
325 spin_unlock_irq(&ctx->ctx_lock);
326 cancel(iocb, &res);
327 spin_lock_irq(&ctx->ctx_lock);
328 }
329 }
330
331 if (!ctx->reqs_active)
332 goto out;
333
334 add_wait_queue(&ctx->wait, &wait);
335 set_task_state(tsk, TASK_UNINTERRUPTIBLE);
336 while (ctx->reqs_active) {
337 spin_unlock_irq(&ctx->ctx_lock);
338 io_schedule();
339 set_task_state(tsk, TASK_UNINTERRUPTIBLE);
340 spin_lock_irq(&ctx->ctx_lock);
341 }
342 __set_task_state(tsk, TASK_RUNNING);
343 remove_wait_queue(&ctx->wait, &wait);
344
345out:
346 spin_unlock_irq(&ctx->ctx_lock);
347}
348
349
350
351
352ssize_t wait_on_sync_kiocb(struct kiocb *iocb)
353{
354 while (iocb->ki_users) {
355 set_current_state(TASK_UNINTERRUPTIBLE);
356 if (!iocb->ki_users)
357 break;
358 io_schedule();
359 }
360 __set_current_state(TASK_RUNNING);
361 return iocb->ki_user_data;
362}
363EXPORT_SYMBOL(wait_on_sync_kiocb);
364
365
366
367
368
369
370
371
372void exit_aio(struct mm_struct *mm)
373{
374 struct kioctx *ctx;
375
376 while (!hlist_empty(&mm->ioctx_list)) {
377 ctx = hlist_entry(mm->ioctx_list.first, struct kioctx, list);
378 hlist_del_rcu(&ctx->list);
379
380 kill_ctx(ctx);
381
382 if (1 != atomic_read(&ctx->users))
383 printk(KERN_DEBUG
384 "exit_aio:ioctx still alive: %d %d %d\n",
385 atomic_read(&ctx->users), ctx->dead,
386 ctx->reqs_active);
387
388
389
390
391
392
393
394
395
396
397 ctx->ring_info.mmap_size = 0;
398 put_ioctx(ctx);
399 }
400}
401
402
403
404
405
406
407
408
409
410
411
412static struct kiocb *__aio_get_req(struct kioctx *ctx)
413{
414 struct kiocb *req = NULL;
415
416 req = kmem_cache_alloc(kiocb_cachep, GFP_KERNEL);
417 if (unlikely(!req))
418 return NULL;
419
420 req->ki_flags = 0;
421 req->ki_users = 2;
422 req->ki_key = 0;
423 req->ki_ctx = ctx;
424 req->ki_cancel = NULL;
425 req->ki_retry = NULL;
426 req->ki_dtor = NULL;
427 req->private = NULL;
428 req->ki_iovec = NULL;
429 INIT_LIST_HEAD(&req->ki_run_list);
430 req->ki_eventfd = NULL;
431
432 return req;
433}
434
435
436
437
438
439#define KIOCB_BATCH_SIZE 32L
440struct kiocb_batch {
441 struct list_head head;
442 long count;
443};
444
445static void kiocb_batch_init(struct kiocb_batch *batch, long total)
446{
447 INIT_LIST_HEAD(&batch->head);
448 batch->count = total;
449}
450
451static void kiocb_batch_free(struct kioctx *ctx, struct kiocb_batch *batch)
452{
453 struct kiocb *req, *n;
454
455 if (list_empty(&batch->head))
456 return;
457
458 spin_lock_irq(&ctx->ctx_lock);
459 list_for_each_entry_safe(req, n, &batch->head, ki_batch) {
460 list_del(&req->ki_batch);
461 list_del(&req->ki_list);
462 kmem_cache_free(kiocb_cachep, req);
463 ctx->reqs_active--;
464 }
465 if (unlikely(!ctx->reqs_active && ctx->dead))
466 wake_up_all(&ctx->wait);
467 spin_unlock_irq(&ctx->ctx_lock);
468}
469
470
471
472
473
474static int kiocb_batch_refill(struct kioctx *ctx, struct kiocb_batch *batch)
475{
476 unsigned short allocated, to_alloc;
477 long avail;
478 struct kiocb *req, *n;
479 struct aio_ring *ring;
480
481 to_alloc = min(batch->count, KIOCB_BATCH_SIZE);
482 for (allocated = 0; allocated < to_alloc; allocated++) {
483 req = __aio_get_req(ctx);
484 if (!req)
485
486 break;
487 list_add(&req->ki_batch, &batch->head);
488 }
489
490 if (allocated == 0)
491 goto out;
492
493 spin_lock_irq(&ctx->ctx_lock);
494 ring = kmap_atomic(ctx->ring_info.ring_pages[0]);
495
496 avail = aio_ring_avail(&ctx->ring_info, ring) - ctx->reqs_active;
497 BUG_ON(avail < 0);
498 if (avail < allocated) {
499
500 list_for_each_entry_safe(req, n, &batch->head, ki_batch) {
501 list_del(&req->ki_batch);
502 kmem_cache_free(kiocb_cachep, req);
503 if (--allocated <= avail)
504 break;
505 }
506 }
507
508 batch->count -= allocated;
509 list_for_each_entry(req, &batch->head, ki_batch) {
510 list_add(&req->ki_list, &ctx->active_reqs);
511 ctx->reqs_active++;
512 }
513
514 kunmap_atomic(ring);
515 spin_unlock_irq(&ctx->ctx_lock);
516
517out:
518 return allocated;
519}
520
521static inline struct kiocb *aio_get_req(struct kioctx *ctx,
522 struct kiocb_batch *batch)
523{
524 struct kiocb *req;
525
526 if (list_empty(&batch->head))
527 if (kiocb_batch_refill(ctx, batch) == 0)
528 return NULL;
529 req = list_first_entry(&batch->head, struct kiocb, ki_batch);
530 list_del(&req->ki_batch);
531 return req;
532}
533
534static inline void really_put_req(struct kioctx *ctx, struct kiocb *req)
535{
536 assert_spin_locked(&ctx->ctx_lock);
537
538 if (req->ki_eventfd != NULL)
539 eventfd_ctx_put(req->ki_eventfd);
540 if (req->ki_dtor)
541 req->ki_dtor(req);
542 if (req->ki_iovec != &req->ki_inline_vec)
543 kfree(req->ki_iovec);
544 kmem_cache_free(kiocb_cachep, req);
545 ctx->reqs_active--;
546
547 if (unlikely(!ctx->reqs_active && ctx->dead))
548 wake_up_all(&ctx->wait);
549}
550
551
552
553
554static int __aio_put_req(struct kioctx *ctx, struct kiocb *req)
555{
556 dprintk(KERN_DEBUG "aio_put(%p): f_count=%ld\n",
557 req, atomic_long_read(&req->ki_filp->f_count));
558
559 assert_spin_locked(&ctx->ctx_lock);
560
561 req->ki_users--;
562 BUG_ON(req->ki_users < 0);
563 if (likely(req->ki_users))
564 return 0;
565 list_del(&req->ki_list);
566 req->ki_cancel = NULL;
567 req->ki_retry = NULL;
568
569 fput(req->ki_filp);
570 req->ki_filp = NULL;
571 really_put_req(ctx, req);
572 return 1;
573}
574
575
576
577
578
579int aio_put_req(struct kiocb *req)
580{
581 struct kioctx *ctx = req->ki_ctx;
582 int ret;
583 spin_lock_irq(&ctx->ctx_lock);
584 ret = __aio_put_req(ctx, req);
585 spin_unlock_irq(&ctx->ctx_lock);
586 return ret;
587}
588EXPORT_SYMBOL(aio_put_req);
589
590static struct kioctx *lookup_ioctx(unsigned long ctx_id)
591{
592 struct mm_struct *mm = current->mm;
593 struct kioctx *ctx, *ret = NULL;
594
595 rcu_read_lock();
596
597 hlist_for_each_entry_rcu(ctx, &mm->ioctx_list, list) {
598
599
600
601
602
603
604 if (ctx->user_id == ctx_id && !ctx->dead && try_get_ioctx(ctx)){
605 ret = ctx;
606 break;
607 }
608 }
609
610 rcu_read_unlock();
611 return ret;
612}
613
614
615
616
617
618
619
620
621
622
623static inline int __queue_kicked_iocb(struct kiocb *iocb)
624{
625 struct kioctx *ctx = iocb->ki_ctx;
626
627 assert_spin_locked(&ctx->ctx_lock);
628
629 if (list_empty(&iocb->ki_run_list)) {
630 list_add_tail(&iocb->ki_run_list,
631 &ctx->run_list);
632 return 1;
633 }
634 return 0;
635}
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659static ssize_t aio_run_iocb(struct kiocb *iocb)
660{
661 struct kioctx *ctx = iocb->ki_ctx;
662 ssize_t (*retry)(struct kiocb *);
663 ssize_t ret;
664
665 if (!(retry = iocb->ki_retry)) {
666 printk("aio_run_iocb: iocb->ki_retry = NULL\n");
667 return 0;
668 }
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689 kiocbClearKicked(iocb);
690
691
692
693
694
695
696
697 iocb->ki_run_list.next = iocb->ki_run_list.prev = NULL;
698 spin_unlock_irq(&ctx->ctx_lock);
699
700
701 if (kiocbIsCancelled(iocb)) {
702 ret = -EINTR;
703 aio_complete(iocb, ret, 0);
704
705 goto out;
706 }
707
708
709
710
711
712 ret = retry(iocb);
713
714 if (ret != -EIOCBRETRY && ret != -EIOCBQUEUED) {
715
716
717
718
719 if (unlikely(ret == -ERESTARTSYS || ret == -ERESTARTNOINTR ||
720 ret == -ERESTARTNOHAND || ret == -ERESTART_RESTARTBLOCK))
721 ret = -EINTR;
722 aio_complete(iocb, ret, 0);
723 }
724out:
725 spin_lock_irq(&ctx->ctx_lock);
726
727 if (-EIOCBRETRY == ret) {
728
729
730
731
732
733
734
735
736 INIT_LIST_HEAD(&iocb->ki_run_list);
737
738
739 if (kiocbIsKicked(iocb)) {
740 __queue_kicked_iocb(iocb);
741
742
743
744
745
746
747
748 aio_queue_work(ctx);
749 }
750 }
751 return ret;
752}
753
754
755
756
757
758
759
760
761static int __aio_run_iocbs(struct kioctx *ctx)
762{
763 struct kiocb *iocb;
764 struct list_head run_list;
765
766 assert_spin_locked(&ctx->ctx_lock);
767
768 list_replace_init(&ctx->run_list, &run_list);
769 while (!list_empty(&run_list)) {
770 iocb = list_entry(run_list.next, struct kiocb,
771 ki_run_list);
772 list_del(&iocb->ki_run_list);
773
774
775
776 iocb->ki_users++;
777 aio_run_iocb(iocb);
778 __aio_put_req(ctx, iocb);
779 }
780 if (!list_empty(&ctx->run_list))
781 return 1;
782 return 0;
783}
784
785static void aio_queue_work(struct kioctx * ctx)
786{
787 unsigned long timeout;
788
789
790
791
792 smp_mb();
793 if (waitqueue_active(&ctx->wait))
794 timeout = 1;
795 else
796 timeout = HZ/10;
797 queue_delayed_work(aio_wq, &ctx->wq, timeout);
798}
799
800
801
802
803
804
805
806
807static inline void aio_run_all_iocbs(struct kioctx *ctx)
808{
809 spin_lock_irq(&ctx->ctx_lock);
810 while (__aio_run_iocbs(ctx))
811 ;
812 spin_unlock_irq(&ctx->ctx_lock);
813}
814
815
816
817
818
819
820
821
822
823
824static void aio_kick_handler(struct work_struct *work)
825{
826 struct kioctx *ctx = container_of(work, struct kioctx, wq.work);
827 mm_segment_t oldfs = get_fs();
828 struct mm_struct *mm;
829 int requeue;
830
831 set_fs(USER_DS);
832 use_mm(ctx->mm);
833 spin_lock_irq(&ctx->ctx_lock);
834 requeue =__aio_run_iocbs(ctx);
835 mm = ctx->mm;
836 spin_unlock_irq(&ctx->ctx_lock);
837 unuse_mm(mm);
838 set_fs(oldfs);
839
840
841
842 if (requeue)
843 queue_delayed_work(aio_wq, &ctx->wq, 0);
844}
845
846
847
848
849
850
851
852static void try_queue_kicked_iocb(struct kiocb *iocb)
853{
854 struct kioctx *ctx = iocb->ki_ctx;
855 unsigned long flags;
856 int run = 0;
857
858 spin_lock_irqsave(&ctx->ctx_lock, flags);
859
860
861 if (!kiocbTryKick(iocb))
862 run = __queue_kicked_iocb(iocb);
863 spin_unlock_irqrestore(&ctx->ctx_lock, flags);
864 if (run)
865 aio_queue_work(ctx);
866}
867
868
869
870
871
872
873
874
875void kick_iocb(struct kiocb *iocb)
876{
877
878
879 if (is_sync_kiocb(iocb)) {
880 kiocbSetKicked(iocb);
881 wake_up_process(iocb->ki_obj.tsk);
882 return;
883 }
884
885 try_queue_kicked_iocb(iocb);
886}
887EXPORT_SYMBOL(kick_iocb);
888
889
890
891
892
893
894int aio_complete(struct kiocb *iocb, long res, long res2)
895{
896 struct kioctx *ctx = iocb->ki_ctx;
897 struct aio_ring_info *info;
898 struct aio_ring *ring;
899 struct io_event *event;
900 unsigned long flags;
901 unsigned long tail;
902 int ret;
903
904
905
906
907
908
909
910
911 if (is_sync_kiocb(iocb)) {
912 BUG_ON(iocb->ki_users != 1);
913 iocb->ki_user_data = res;
914 iocb->ki_users = 0;
915 wake_up_process(iocb->ki_obj.tsk);
916 return 1;
917 }
918
919 info = &ctx->ring_info;
920
921
922
923
924
925
926
927 spin_lock_irqsave(&ctx->ctx_lock, flags);
928
929 if (iocb->ki_run_list.prev && !list_empty(&iocb->ki_run_list))
930 list_del_init(&iocb->ki_run_list);
931
932
933
934
935
936 if (kiocbIsCancelled(iocb))
937 goto put_rq;
938
939 ring = kmap_atomic(info->ring_pages[0]);
940
941 tail = info->tail;
942 event = aio_ring_event(info, tail);
943 if (++tail >= info->nr)
944 tail = 0;
945
946 event->obj = (u64)(unsigned long)iocb->ki_obj.user;
947 event->data = iocb->ki_user_data;
948 event->res = res;
949 event->res2 = res2;
950
951 dprintk("aio_complete: %p[%lu]: %p: %p %Lx %lx %lx\n",
952 ctx, tail, iocb, iocb->ki_obj.user, iocb->ki_user_data,
953 res, res2);
954
955
956
957
958 smp_wmb();
959
960 info->tail = tail;
961 ring->tail = tail;
962
963 put_aio_ring_event(event);
964 kunmap_atomic(ring);
965
966 pr_debug("added to ring %p at [%lu]\n", iocb, tail);
967
968
969
970
971
972
973 if (iocb->ki_eventfd != NULL)
974 eventfd_signal(iocb->ki_eventfd, 1);
975
976put_rq:
977
978 ret = __aio_put_req(ctx, iocb);
979
980
981
982
983
984
985
986 smp_mb();
987
988 if (waitqueue_active(&ctx->wait))
989 wake_up(&ctx->wait);
990
991 spin_unlock_irqrestore(&ctx->ctx_lock, flags);
992 return ret;
993}
994EXPORT_SYMBOL(aio_complete);
995
996
997
998
999
1000
1001
1002static int aio_read_evt(struct kioctx *ioctx, struct io_event *ent)
1003{
1004 struct aio_ring_info *info = &ioctx->ring_info;
1005 struct aio_ring *ring;
1006 unsigned long head;
1007 int ret = 0;
1008
1009 ring = kmap_atomic(info->ring_pages[0]);
1010 dprintk("in aio_read_evt h%lu t%lu m%lu\n",
1011 (unsigned long)ring->head, (unsigned long)ring->tail,
1012 (unsigned long)ring->nr);
1013
1014 if (ring->head == ring->tail)
1015 goto out;
1016
1017 spin_lock(&info->ring_lock);
1018
1019 head = ring->head % info->nr;
1020 if (head != ring->tail) {
1021 struct io_event *evp = aio_ring_event(info, head);
1022 *ent = *evp;
1023 head = (head + 1) % info->nr;
1024 smp_mb();
1025 ring->head = head;
1026 ret = 1;
1027 put_aio_ring_event(evp);
1028 }
1029 spin_unlock(&info->ring_lock);
1030
1031out:
1032 dprintk("leaving aio_read_evt: %d h%lu t%lu\n", ret,
1033 (unsigned long)ring->head, (unsigned long)ring->tail);
1034 kunmap_atomic(ring);
1035 return ret;
1036}
1037
1038struct aio_timeout {
1039 struct timer_list timer;
1040 int timed_out;
1041 struct task_struct *p;
1042};
1043
1044static void timeout_func(unsigned long data)
1045{
1046 struct aio_timeout *to = (struct aio_timeout *)data;
1047
1048 to->timed_out = 1;
1049 wake_up_process(to->p);
1050}
1051
1052static inline void init_timeout(struct aio_timeout *to)
1053{
1054 setup_timer_on_stack(&to->timer, timeout_func, (unsigned long) to);
1055 to->timed_out = 0;
1056 to->p = current;
1057}
1058
1059static inline void set_timeout(long start_jiffies, struct aio_timeout *to,
1060 const struct timespec *ts)
1061{
1062 to->timer.expires = start_jiffies + timespec_to_jiffies(ts);
1063 if (time_after(to->timer.expires, jiffies))
1064 add_timer(&to->timer);
1065 else
1066 to->timed_out = 1;
1067}
1068
1069static inline void clear_timeout(struct aio_timeout *to)
1070{
1071 del_singleshot_timer_sync(&to->timer);
1072}
1073
1074static int read_events(struct kioctx *ctx,
1075 long min_nr, long nr,
1076 struct io_event __user *event,
1077 struct timespec __user *timeout)
1078{
1079 long start_jiffies = jiffies;
1080 struct task_struct *tsk = current;
1081 DECLARE_WAITQUEUE(wait, tsk);
1082 int ret;
1083 int i = 0;
1084 struct io_event ent;
1085 struct aio_timeout to;
1086 int retry = 0;
1087
1088
1089
1090
1091 memset(&ent, 0, sizeof(ent));
1092retry:
1093 ret = 0;
1094 while (likely(i < nr)) {
1095 ret = aio_read_evt(ctx, &ent);
1096 if (unlikely(ret <= 0))
1097 break;
1098
1099 dprintk("read event: %Lx %Lx %Lx %Lx\n",
1100 ent.data, ent.obj, ent.res, ent.res2);
1101
1102
1103 ret = -EFAULT;
1104 if (unlikely(copy_to_user(event, &ent, sizeof(ent)))) {
1105 dprintk("aio: lost an event due to EFAULT.\n");
1106 break;
1107 }
1108 ret = 0;
1109
1110
1111 event ++;
1112 i ++;
1113 }
1114
1115 if (min_nr <= i)
1116 return i;
1117 if (ret)
1118 return ret;
1119
1120
1121
1122
1123 if (!retry && unlikely(!list_empty(&ctx->run_list))) {
1124 retry = 1;
1125 aio_run_all_iocbs(ctx);
1126 goto retry;
1127 }
1128
1129 init_timeout(&to);
1130 if (timeout) {
1131 struct timespec ts;
1132 ret = -EFAULT;
1133 if (unlikely(copy_from_user(&ts, timeout, sizeof(ts))))
1134 goto out;
1135
1136 set_timeout(start_jiffies, &to, &ts);
1137 }
1138
1139 while (likely(i < nr)) {
1140 add_wait_queue_exclusive(&ctx->wait, &wait);
1141 do {
1142 set_task_state(tsk, TASK_INTERRUPTIBLE);
1143 ret = aio_read_evt(ctx, &ent);
1144 if (ret)
1145 break;
1146 if (min_nr <= i)
1147 break;
1148 if (unlikely(ctx->dead)) {
1149 ret = -EINVAL;
1150 break;
1151 }
1152 if (to.timed_out)
1153 break;
1154
1155
1156 if (ctx->reqs_active)
1157 io_schedule();
1158 else
1159 schedule();
1160 if (signal_pending(tsk)) {
1161 ret = -EINTR;
1162 break;
1163 }
1164
1165 } while (1) ;
1166
1167 set_task_state(tsk, TASK_RUNNING);
1168 remove_wait_queue(&ctx->wait, &wait);
1169
1170 if (unlikely(ret <= 0))
1171 break;
1172
1173 ret = -EFAULT;
1174 if (unlikely(copy_to_user(event, &ent, sizeof(ent)))) {
1175 dprintk("aio: lost an event due to EFAULT.\n");
1176 break;
1177 }
1178
1179
1180 event ++;
1181 i ++;
1182 }
1183
1184 if (timeout)
1185 clear_timeout(&to);
1186out:
1187 destroy_timer_on_stack(&to.timer);
1188 return i ? i : ret;
1189}
1190
1191
1192
1193
1194static void io_destroy(struct kioctx *ioctx)
1195{
1196 struct mm_struct *mm = current->mm;
1197 int was_dead;
1198
1199
1200 spin_lock(&mm->ioctx_lock);
1201 was_dead = ioctx->dead;
1202 ioctx->dead = 1;
1203 hlist_del_rcu(&ioctx->list);
1204 spin_unlock(&mm->ioctx_lock);
1205
1206 dprintk("aio_release(%p)\n", ioctx);
1207 if (likely(!was_dead))
1208 put_ioctx(ioctx);
1209
1210 kill_ctx(ioctx);
1211
1212
1213
1214
1215
1216
1217 wake_up_all(&ioctx->wait);
1218}
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233SYSCALL_DEFINE2(io_setup, unsigned, nr_events, aio_context_t __user *, ctxp)
1234{
1235 struct kioctx *ioctx = NULL;
1236 unsigned long ctx;
1237 long ret;
1238
1239 ret = get_user(ctx, ctxp);
1240 if (unlikely(ret))
1241 goto out;
1242
1243 ret = -EINVAL;
1244 if (unlikely(ctx || nr_events == 0)) {
1245 pr_debug("EINVAL: io_setup: ctx %lu nr_events %u\n",
1246 ctx, nr_events);
1247 goto out;
1248 }
1249
1250 ioctx = ioctx_alloc(nr_events);
1251 ret = PTR_ERR(ioctx);
1252 if (!IS_ERR(ioctx)) {
1253 ret = put_user(ioctx->user_id, ctxp);
1254 if (ret)
1255 io_destroy(ioctx);
1256 put_ioctx(ioctx);
1257 }
1258
1259out:
1260 return ret;
1261}
1262
1263
1264
1265
1266
1267
1268
1269SYSCALL_DEFINE1(io_destroy, aio_context_t, ctx)
1270{
1271 struct kioctx *ioctx = lookup_ioctx(ctx);
1272 if (likely(NULL != ioctx)) {
1273 io_destroy(ioctx);
1274 put_ioctx(ioctx);
1275 return 0;
1276 }
1277 pr_debug("EINVAL: io_destroy: invalid context id\n");
1278 return -EINVAL;
1279}
1280
1281static void aio_advance_iovec(struct kiocb *iocb, ssize_t ret)
1282{
1283 struct iovec *iov = &iocb->ki_iovec[iocb->ki_cur_seg];
1284
1285 BUG_ON(ret <= 0);
1286
1287 while (iocb->ki_cur_seg < iocb->ki_nr_segs && ret > 0) {
1288 ssize_t this = min((ssize_t)iov->iov_len, ret);
1289 iov->iov_base += this;
1290 iov->iov_len -= this;
1291 iocb->ki_left -= this;
1292 ret -= this;
1293 if (iov->iov_len == 0) {
1294 iocb->ki_cur_seg++;
1295 iov++;
1296 }
1297 }
1298
1299
1300
1301 BUG_ON(ret > 0 && iocb->ki_left == 0);
1302}
1303
1304static ssize_t aio_rw_vect_retry(struct kiocb *iocb)
1305{
1306 struct file *file = iocb->ki_filp;
1307 struct address_space *mapping = file->f_mapping;
1308 struct inode *inode = mapping->host;
1309 ssize_t (*rw_op)(struct kiocb *, const struct iovec *,
1310 unsigned long, loff_t);
1311 ssize_t ret = 0;
1312 unsigned short opcode;
1313
1314 if ((iocb->ki_opcode == IOCB_CMD_PREADV) ||
1315 (iocb->ki_opcode == IOCB_CMD_PREAD)) {
1316 rw_op = file->f_op->aio_read;
1317 opcode = IOCB_CMD_PREADV;
1318 } else {
1319 rw_op = file->f_op->aio_write;
1320 opcode = IOCB_CMD_PWRITEV;
1321 }
1322
1323
1324 if (iocb->ki_pos < 0)
1325 return -EINVAL;
1326
1327 do {
1328 ret = rw_op(iocb, &iocb->ki_iovec[iocb->ki_cur_seg],
1329 iocb->ki_nr_segs - iocb->ki_cur_seg,
1330 iocb->ki_pos);
1331 if (ret > 0)
1332 aio_advance_iovec(iocb, ret);
1333
1334
1335
1336 } while (ret > 0 && iocb->ki_left > 0 &&
1337 (opcode == IOCB_CMD_PWRITEV ||
1338 (!S_ISFIFO(inode->i_mode) && !S_ISSOCK(inode->i_mode))));
1339
1340
1341
1342 if ((ret == 0) || (iocb->ki_left == 0))
1343 ret = iocb->ki_nbytes - iocb->ki_left;
1344
1345
1346
1347 if (opcode == IOCB_CMD_PWRITEV
1348 && ret < 0 && ret != -EIOCBQUEUED && ret != -EIOCBRETRY
1349 && iocb->ki_nbytes - iocb->ki_left)
1350 ret = iocb->ki_nbytes - iocb->ki_left;
1351
1352 return ret;
1353}
1354
1355static ssize_t aio_fdsync(struct kiocb *iocb)
1356{
1357 struct file *file = iocb->ki_filp;
1358 ssize_t ret = -EINVAL;
1359
1360 if (file->f_op->aio_fsync)
1361 ret = file->f_op->aio_fsync(iocb, 1);
1362 return ret;
1363}
1364
1365static ssize_t aio_fsync(struct kiocb *iocb)
1366{
1367 struct file *file = iocb->ki_filp;
1368 ssize_t ret = -EINVAL;
1369
1370 if (file->f_op->aio_fsync)
1371 ret = file->f_op->aio_fsync(iocb, 0);
1372 return ret;
1373}
1374
1375static ssize_t aio_setup_vectored_rw(int type, struct kiocb *kiocb, bool compat)
1376{
1377 ssize_t ret;
1378
1379#ifdef CONFIG_COMPAT
1380 if (compat)
1381 ret = compat_rw_copy_check_uvector(type,
1382 (struct compat_iovec __user *)kiocb->ki_buf,
1383 kiocb->ki_nbytes, 1, &kiocb->ki_inline_vec,
1384 &kiocb->ki_iovec);
1385 else
1386#endif
1387 ret = rw_copy_check_uvector(type,
1388 (struct iovec __user *)kiocb->ki_buf,
1389 kiocb->ki_nbytes, 1, &kiocb->ki_inline_vec,
1390 &kiocb->ki_iovec);
1391 if (ret < 0)
1392 goto out;
1393
1394 ret = rw_verify_area(type, kiocb->ki_filp, &kiocb->ki_pos, ret);
1395 if (ret < 0)
1396 goto out;
1397
1398 kiocb->ki_nr_segs = kiocb->ki_nbytes;
1399 kiocb->ki_cur_seg = 0;
1400
1401 kiocb->ki_nbytes = ret;
1402 kiocb->ki_left = ret;
1403
1404 ret = 0;
1405out:
1406 return ret;
1407}
1408
1409static ssize_t aio_setup_single_vector(int type, struct file * file, struct kiocb *kiocb)
1410{
1411 int bytes;
1412
1413 bytes = rw_verify_area(type, file, &kiocb->ki_pos, kiocb->ki_left);
1414 if (bytes < 0)
1415 return bytes;
1416
1417 kiocb->ki_iovec = &kiocb->ki_inline_vec;
1418 kiocb->ki_iovec->iov_base = kiocb->ki_buf;
1419 kiocb->ki_iovec->iov_len = bytes;
1420 kiocb->ki_nr_segs = 1;
1421 kiocb->ki_cur_seg = 0;
1422 return 0;
1423}
1424
1425
1426
1427
1428
1429
1430static ssize_t aio_setup_iocb(struct kiocb *kiocb, bool compat)
1431{
1432 struct file *file = kiocb->ki_filp;
1433 ssize_t ret = 0;
1434
1435 switch (kiocb->ki_opcode) {
1436 case IOCB_CMD_PREAD:
1437 ret = -EBADF;
1438 if (unlikely(!(file->f_mode & FMODE_READ)))
1439 break;
1440 ret = -EFAULT;
1441 if (unlikely(!access_ok(VERIFY_WRITE, kiocb->ki_buf,
1442 kiocb->ki_left)))
1443 break;
1444 ret = aio_setup_single_vector(READ, file, kiocb);
1445 if (ret)
1446 break;
1447 ret = -EINVAL;
1448 if (file->f_op->aio_read)
1449 kiocb->ki_retry = aio_rw_vect_retry;
1450 break;
1451 case IOCB_CMD_PWRITE:
1452 ret = -EBADF;
1453 if (unlikely(!(file->f_mode & FMODE_WRITE)))
1454 break;
1455 ret = -EFAULT;
1456 if (unlikely(!access_ok(VERIFY_READ, kiocb->ki_buf,
1457 kiocb->ki_left)))
1458 break;
1459 ret = aio_setup_single_vector(WRITE, file, kiocb);
1460 if (ret)
1461 break;
1462 ret = -EINVAL;
1463 if (file->f_op->aio_write)
1464 kiocb->ki_retry = aio_rw_vect_retry;
1465 break;
1466 case IOCB_CMD_PREADV:
1467 ret = -EBADF;
1468 if (unlikely(!(file->f_mode & FMODE_READ)))
1469 break;
1470 ret = aio_setup_vectored_rw(READ, kiocb, compat);
1471 if (ret)
1472 break;
1473 ret = -EINVAL;
1474 if (file->f_op->aio_read)
1475 kiocb->ki_retry = aio_rw_vect_retry;
1476 break;
1477 case IOCB_CMD_PWRITEV:
1478 ret = -EBADF;
1479 if (unlikely(!(file->f_mode & FMODE_WRITE)))
1480 break;
1481 ret = aio_setup_vectored_rw(WRITE, kiocb, compat);
1482 if (ret)
1483 break;
1484 ret = -EINVAL;
1485 if (file->f_op->aio_write)
1486 kiocb->ki_retry = aio_rw_vect_retry;
1487 break;
1488 case IOCB_CMD_FDSYNC:
1489 ret = -EINVAL;
1490 if (file->f_op->aio_fsync)
1491 kiocb->ki_retry = aio_fdsync;
1492 break;
1493 case IOCB_CMD_FSYNC:
1494 ret = -EINVAL;
1495 if (file->f_op->aio_fsync)
1496 kiocb->ki_retry = aio_fsync;
1497 break;
1498 default:
1499 dprintk("EINVAL: io_submit: no operation provided\n");
1500 ret = -EINVAL;
1501 }
1502
1503 if (!kiocb->ki_retry)
1504 return ret;
1505
1506 return 0;
1507}
1508
1509static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
1510 struct iocb *iocb, struct kiocb_batch *batch,
1511 bool compat)
1512{
1513 struct kiocb *req;
1514 struct file *file;
1515 ssize_t ret;
1516
1517
1518 if (unlikely(iocb->aio_reserved1 || iocb->aio_reserved2)) {
1519 pr_debug("EINVAL: io_submit: reserve field set\n");
1520 return -EINVAL;
1521 }
1522
1523
1524 if (unlikely(
1525 (iocb->aio_buf != (unsigned long)iocb->aio_buf) ||
1526 (iocb->aio_nbytes != (size_t)iocb->aio_nbytes) ||
1527 ((ssize_t)iocb->aio_nbytes < 0)
1528 )) {
1529 pr_debug("EINVAL: io_submit: overflow check\n");
1530 return -EINVAL;
1531 }
1532
1533 file = fget(iocb->aio_fildes);
1534 if (unlikely(!file))
1535 return -EBADF;
1536
1537 req = aio_get_req(ctx, batch);
1538 if (unlikely(!req)) {
1539 fput(file);
1540 return -EAGAIN;
1541 }
1542 req->ki_filp = file;
1543 if (iocb->aio_flags & IOCB_FLAG_RESFD) {
1544
1545
1546
1547
1548
1549
1550 req->ki_eventfd = eventfd_ctx_fdget((int) iocb->aio_resfd);
1551 if (IS_ERR(req->ki_eventfd)) {
1552 ret = PTR_ERR(req->ki_eventfd);
1553 req->ki_eventfd = NULL;
1554 goto out_put_req;
1555 }
1556 }
1557
1558 ret = put_user(req->ki_key, &user_iocb->aio_key);
1559 if (unlikely(ret)) {
1560 dprintk("EFAULT: aio_key\n");
1561 goto out_put_req;
1562 }
1563
1564 req->ki_obj.user = user_iocb;
1565 req->ki_user_data = iocb->aio_data;
1566 req->ki_pos = iocb->aio_offset;
1567
1568 req->ki_buf = (char __user *)(unsigned long)iocb->aio_buf;
1569 req->ki_left = req->ki_nbytes = iocb->aio_nbytes;
1570 req->ki_opcode = iocb->aio_lio_opcode;
1571
1572 ret = aio_setup_iocb(req, compat);
1573
1574 if (ret)
1575 goto out_put_req;
1576
1577 spin_lock_irq(&ctx->ctx_lock);
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590 if (ctx->dead) {
1591 spin_unlock_irq(&ctx->ctx_lock);
1592 ret = -EINVAL;
1593 goto out_put_req;
1594 }
1595 aio_run_iocb(req);
1596 if (!list_empty(&ctx->run_list)) {
1597
1598 while (__aio_run_iocbs(ctx))
1599 ;
1600 }
1601 spin_unlock_irq(&ctx->ctx_lock);
1602
1603 aio_put_req(req);
1604 return 0;
1605
1606out_put_req:
1607 aio_put_req(req);
1608 aio_put_req(req);
1609 return ret;
1610}
1611
1612long do_io_submit(aio_context_t ctx_id, long nr,
1613 struct iocb __user *__user *iocbpp, bool compat)
1614{
1615 struct kioctx *ctx;
1616 long ret = 0;
1617 int i = 0;
1618 struct blk_plug plug;
1619 struct kiocb_batch batch;
1620
1621 if (unlikely(nr < 0))
1622 return -EINVAL;
1623
1624 if (unlikely(nr > LONG_MAX/sizeof(*iocbpp)))
1625 nr = LONG_MAX/sizeof(*iocbpp);
1626
1627 if (unlikely(!access_ok(VERIFY_READ, iocbpp, (nr*sizeof(*iocbpp)))))
1628 return -EFAULT;
1629
1630 ctx = lookup_ioctx(ctx_id);
1631 if (unlikely(!ctx)) {
1632 pr_debug("EINVAL: io_submit: invalid context id\n");
1633 return -EINVAL;
1634 }
1635
1636 kiocb_batch_init(&batch, nr);
1637
1638 blk_start_plug(&plug);
1639
1640
1641
1642
1643
1644 for (i=0; i<nr; i++) {
1645 struct iocb __user *user_iocb;
1646 struct iocb tmp;
1647
1648 if (unlikely(__get_user(user_iocb, iocbpp + i))) {
1649 ret = -EFAULT;
1650 break;
1651 }
1652
1653 if (unlikely(copy_from_user(&tmp, user_iocb, sizeof(tmp)))) {
1654 ret = -EFAULT;
1655 break;
1656 }
1657
1658 ret = io_submit_one(ctx, user_iocb, &tmp, &batch, compat);
1659 if (ret)
1660 break;
1661 }
1662 blk_finish_plug(&plug);
1663
1664 kiocb_batch_free(ctx, &batch);
1665 put_ioctx(ctx);
1666 return i ? i : ret;
1667}
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681SYSCALL_DEFINE3(io_submit, aio_context_t, ctx_id, long, nr,
1682 struct iocb __user * __user *, iocbpp)
1683{
1684 return do_io_submit(ctx_id, nr, iocbpp, 0);
1685}
1686
1687
1688
1689
1690static struct kiocb *lookup_kiocb(struct kioctx *ctx, struct iocb __user *iocb,
1691 u32 key)
1692{
1693 struct list_head *pos;
1694
1695 assert_spin_locked(&ctx->ctx_lock);
1696
1697
1698 list_for_each(pos, &ctx->active_reqs) {
1699 struct kiocb *kiocb = list_kiocb(pos);
1700 if (kiocb->ki_obj.user == iocb && kiocb->ki_key == key)
1701 return kiocb;
1702 }
1703 return NULL;
1704}
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb,
1717 struct io_event __user *, result)
1718{
1719 int (*cancel)(struct kiocb *iocb, struct io_event *res);
1720 struct kioctx *ctx;
1721 struct kiocb *kiocb;
1722 u32 key;
1723 int ret;
1724
1725 ret = get_user(key, &iocb->aio_key);
1726 if (unlikely(ret))
1727 return -EFAULT;
1728
1729 ctx = lookup_ioctx(ctx_id);
1730 if (unlikely(!ctx))
1731 return -EINVAL;
1732
1733 spin_lock_irq(&ctx->ctx_lock);
1734 ret = -EAGAIN;
1735 kiocb = lookup_kiocb(ctx, iocb, key);
1736 if (kiocb && kiocb->ki_cancel) {
1737 cancel = kiocb->ki_cancel;
1738 kiocb->ki_users ++;
1739 kiocbSetCancelled(kiocb);
1740 } else
1741 cancel = NULL;
1742 spin_unlock_irq(&ctx->ctx_lock);
1743
1744 if (NULL != cancel) {
1745 struct io_event tmp;
1746 pr_debug("calling cancel\n");
1747 memset(&tmp, 0, sizeof(tmp));
1748 tmp.obj = (u64)(unsigned long)kiocb->ki_obj.user;
1749 tmp.data = kiocb->ki_user_data;
1750 ret = cancel(kiocb, &tmp);
1751 if (!ret) {
1752
1753
1754
1755 if (copy_to_user(result, &tmp, sizeof(tmp)))
1756 ret = -EFAULT;
1757 }
1758 } else
1759 ret = -EINVAL;
1760
1761 put_ioctx(ctx);
1762
1763 return ret;
1764}
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779SYSCALL_DEFINE5(io_getevents, aio_context_t, ctx_id,
1780 long, min_nr,
1781 long, nr,
1782 struct io_event __user *, events,
1783 struct timespec __user *, timeout)
1784{
1785 struct kioctx *ioctx = lookup_ioctx(ctx_id);
1786 long ret = -EINVAL;
1787
1788 if (likely(ioctx)) {
1789 if (likely(min_nr <= nr && min_nr >= 0))
1790 ret = read_events(ioctx, min_nr, nr, events, timeout);
1791 put_ioctx(ioctx);
1792 }
1793
1794 asmlinkage_protect(5, ret, ctx_id, min_nr, nr, events, timeout);
1795 return ret;
1796}
1797