1/*
2 * Copyright (c) 2003-2008 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29
30/*
31 * todo:
32 *		1) ramesh is looking into how to replace taking a reference on
33 *		   	the user's map (vm_map_reference()) since it is believed that
34 *			would not hold the process for us.
35 *		2) david is looking into a way for us to set the priority of the
36 *		   	worker threads to match that of the user's thread when the
37 *		   	async IO was queued.
38 */
39
40
41/*
42 * This file contains support for the POSIX 1003.1B AIO/LIO facility.
43 */
44
45#include <sys/systm.h>
46#include <sys/fcntl.h>
47#include <sys/file_internal.h>
48#include <sys/filedesc.h>
49#include <sys/kernel.h>
50#include <sys/vnode_internal.h>
51#include <sys/malloc.h>
52#include <sys/mount_internal.h>
53#include <sys/param.h>
54#include <sys/proc_internal.h>
55#include <sys/sysctl.h>
56#include <sys/unistd.h>
57#include <sys/user.h>
58
59#include <sys/aio_kern.h>
60#include <sys/sysproto.h>
61
62#include <machine/limits.h>
63
64#include <mach/mach_types.h>
65#include <kern/kern_types.h>
66#include <kern/zalloc.h>
67#include <kern/task.h>
68#include <kern/sched_prim.h>
69
70#include <vm/vm_map.h>
71
72#include <libkern/OSAtomic.h>
73
74#include <sys/kdebug.h>
75#define AIO_work_queued					1
76#define AIO_worker_wake				 	2
77#define AIO_completion_sig				3
78#define AIO_completion_cleanup_wait		4
79#define AIO_completion_cleanup_wake		5
80#define AIO_completion_suspend_wake 	6
81#define AIO_fsync_delay					7
82#define AIO_cancel 						10
83#define AIO_cancel_async_workq			11
84#define AIO_cancel_sync_workq			12
85#define AIO_cancel_activeq				13
86#define AIO_cancel_doneq				14
87#define AIO_fsync						20
88#define AIO_read						30
89#define AIO_write						40
90#define AIO_listio						50
91#define AIO_error						60
92#define AIO_error_val					61
93#define AIO_error_activeq				62
94#define AIO_error_workq					63
95#define	AIO_return						70
96#define	AIO_return_val					71
97#define	AIO_return_activeq				72
98#define	AIO_return_workq				73
99#define AIO_exec						80
100#define AIO_exit						90
101#define AIO_exit_sleep					91
102#define AIO_close						100
103#define AIO_close_sleep					101
104#define AIO_suspend						110
105#define AIO_suspend_sleep				111
106#define AIO_worker_thread				120
107
108#if 0
109#undef KERNEL_DEBUG
110#define KERNEL_DEBUG KERNEL_DEBUG_CONSTANT
111#endif
112
113/*
114 * aio requests queue up on the aio_async_workq or lio_sync_workq (for
115 * lio_listio LIO_WAIT).  Requests then move to the per process aio_activeq
116 * (proc.aio_activeq) when one of our worker threads start the IO.
117 * And finally, requests move to the per process aio_doneq (proc.aio_doneq)
118 * when the IO request completes.  The request remains on aio_doneq until
119 * user process calls aio_return or the process exits, either way that is our
120 * trigger to release aio resources.
121 */
122typedef struct aio_workq   {
123	TAILQ_HEAD(, aio_workq_entry) 	aioq_entries;
124	int				aioq_count;
125	lck_mtx_t			aioq_mtx;
126	wait_queue_t			aioq_waitq;
127} *aio_workq_t;
128
129#define AIO_NUM_WORK_QUEUES 1
130struct aio_anchor_cb
131{
132	volatile int32_t	aio_inflight_count; 	/* entries that have been taken from a workq */
133	volatile int32_t	aio_done_count; 	/* entries on all done queues (proc.aio_doneq) */
134	volatile int32_t	aio_total_count;	/* total extant entries */
135
136	/* Hash table of queues here */
137	int 			aio_num_workqs;
138	struct aio_workq 	aio_async_workqs[AIO_NUM_WORK_QUEUES];
139};
140typedef struct aio_anchor_cb aio_anchor_cb;
141
142struct aio_lio_context
143{
144	int		io_waiter;
145	int		io_issued;
146	int		io_completed;
147};
148typedef struct aio_lio_context aio_lio_context;
149
150
151/*
152 * Notes on aio sleep / wake channels.
153 * We currently pick a couple fields within the proc structure that will allow
154 * us sleep channels that currently do not collide with any other kernel routines.
155 * At this time, for binary compatibility reasons, we cannot create new proc fields.
156 */
157#define AIO_SUSPEND_SLEEP_CHAN  p_aio_active_count
158#define AIO_CLEANUP_SLEEP_CHAN 	p_aio_total_count
159
160#define ASSERT_AIO_FROM_PROC(aiop, theproc) 	\
161	if ((aiop)->procp != (theproc)) { 	\
162		panic("AIO on a proc list that does not belong to that proc.\n"); \
163	}
164
165/*
166 *  LOCAL PROTOTYPES
167 */
168static void		aio_proc_lock(proc_t procp);
169static void		aio_proc_lock_spin(proc_t procp);
170static void		aio_proc_unlock(proc_t procp);
171static lck_mtx_t*	aio_proc_mutex(proc_t procp);
172static void		aio_proc_move_done_locked(proc_t procp, aio_workq_entry *entryp);
173static void		aio_proc_remove_done_locked(proc_t procp, aio_workq_entry *entryp);
174static int		aio_get_process_count(proc_t procp );
175static int		aio_active_requests_for_process(proc_t procp );
176static int		aio_proc_active_requests_for_file(proc_t procp, int fd);
177static boolean_t	is_already_queued(proc_t procp, user_addr_t aiocbp );
178static boolean_t	should_cancel(aio_workq_entry *entryp, user_addr_t aiocbp, int fd);
179
180static void		aio_entry_lock(aio_workq_entry *entryp);
181static void		aio_entry_lock_spin(aio_workq_entry *entryp);
182static aio_workq_t	aio_entry_workq(aio_workq_entry *entryp);
183static lck_mtx_t*	aio_entry_mutex(__unused aio_workq_entry *entryp);
184static void		aio_workq_remove_entry_locked(aio_workq_t queue, aio_workq_entry *entryp);
185static void		aio_workq_add_entry_locked(aio_workq_t queue, aio_workq_entry *entryp);
186static void		aio_entry_ref_locked(aio_workq_entry *entryp);
187static void		aio_entry_unref_locked(aio_workq_entry *entryp);
188static void		aio_entry_ref(aio_workq_entry *entryp);
189static void		aio_entry_unref(aio_workq_entry *entryp);
190static void		aio_entry_update_for_cancel(aio_workq_entry *entryp, boolean_t cancelled,
191					int wait_for_completion, boolean_t disable_notification);
192static int		aio_entry_try_workq_remove(aio_workq_entry *entryp);
193static boolean_t	aio_delay_fsync_request( aio_workq_entry *entryp );
194static int		aio_free_request(aio_workq_entry *entryp);
195
196static void		aio_workq_init(aio_workq_t wq);
197static void		aio_workq_lock_spin(aio_workq_t wq);
198static void		aio_workq_unlock(aio_workq_t wq);
199static lck_mtx_t*	aio_workq_mutex(aio_workq_t wq);
200
201static void		aio_work_thread( void );
202static aio_workq_entry *aio_get_some_work( void );
203
204static int		aio_get_all_queues_count( void );
205static int		aio_queue_async_request(proc_t procp, user_addr_t aiocbp, int kindOfIO );
206static int		aio_validate( aio_workq_entry *entryp );
207static int 		aio_increment_total_count(void);
208static int 		aio_decrement_total_count(void);
209
210static int		do_aio_cancel_locked(proc_t p, int fd, user_addr_t aiocbp, int wait_for_completion, boolean_t disable_notification );
211static void		do_aio_completion( aio_workq_entry *entryp );
212static int		do_aio_fsync( aio_workq_entry *entryp );
213static int		do_aio_read( aio_workq_entry *entryp );
214static int		do_aio_write( aio_workq_entry *entryp );
215static void 		do_munge_aiocb_user32_to_user( struct user32_aiocb *my_aiocbp, struct user_aiocb *the_user_aiocbp );
216static void 		do_munge_aiocb_user64_to_user( struct user64_aiocb *my_aiocbp, struct user_aiocb *the_user_aiocbp );
217static int	lio_create_entry(proc_t procp,
218					 user_addr_t aiocbp,
219					 void *group_tag,
220					 aio_workq_entry **entrypp );
221static aio_workq_entry *aio_create_queue_entry(proc_t procp,
222					user_addr_t aiocbp,
223					void *group_tag,
224					int kindOfIO);
225static user_addr_t *aio_copy_in_list(proc_t procp, user_addr_t aiocblist, int nent);
226static void		free_lio_context(aio_lio_context* context);
227static void 		aio_enqueue_work( proc_t procp, aio_workq_entry *entryp, int proc_locked);
228
229#define ASSERT_AIO_PROC_LOCK_OWNED(p)	lck_mtx_assert(aio_proc_mutex((p)), LCK_MTX_ASSERT_OWNED)
230#define ASSERT_AIO_WORKQ_LOCK_OWNED(q)	lck_mtx_assert(aio_workq_mutex((q)), LCK_MTX_ASSERT_OWNED)
231#define ASSERT_AIO_ENTRY_LOCK_OWNED(e)	lck_mtx_assert(aio_entry_mutex((e)), LCK_MTX_ASSERT_OWNED)
232
233/*
234 *  EXTERNAL PROTOTYPES
235 */
236
237/* in ...bsd/kern/sys_generic.c */
238extern int dofileread(vfs_context_t ctx, struct fileproc *fp,
239			user_addr_t bufp, user_size_t nbyte,
240			off_t offset, int flags, user_ssize_t *retval );
241extern int dofilewrite(vfs_context_t ctx, struct fileproc *fp,
242			 user_addr_t bufp, user_size_t nbyte, off_t offset,
243			 int flags, user_ssize_t *retval );
244#if DEBUG
245static uint32_t                         lio_contexts_alloced = 0;
246#endif  /* DEBUG */
247
248/*
249 * aio external global variables.
250 */
251extern int aio_max_requests;  			/* AIO_MAX - configurable */
252extern int aio_max_requests_per_process;	/* AIO_PROCESS_MAX - configurable */
253extern int aio_worker_threads;			/* AIO_THREAD_COUNT - configurable */
254
255
256/*
257 * aio static variables.
258 */
259static aio_anchor_cb	aio_anchor;
260static lck_grp_t	*aio_proc_lock_grp;
261static lck_grp_t	*aio_entry_lock_grp;
262static lck_grp_t	*aio_queue_lock_grp;
263static lck_attr_t	*aio_lock_attr;
264static lck_grp_attr_t	*aio_lock_grp_attr;
265static struct zone  	*aio_workq_zonep;
266static lck_mtx_t	aio_entry_mtx;
267static lck_mtx_t	aio_proc_mtx;
268
269static void
270aio_entry_lock(__unused aio_workq_entry *entryp)
271{
272	lck_mtx_lock(&aio_entry_mtx);
273}
274
275static void
276aio_entry_lock_spin(__unused aio_workq_entry *entryp)
277{
278	lck_mtx_lock_spin(&aio_entry_mtx);
279}
280
281static void
282aio_entry_unlock(__unused aio_workq_entry *entryp)
283{
284	lck_mtx_unlock(&aio_entry_mtx);
285}
286
287/* Hash */
288static aio_workq_t
289aio_entry_workq(__unused aio_workq_entry *entryp)
290{
291	return &aio_anchor.aio_async_workqs[0];
292}
293
294static lck_mtx_t*
295aio_entry_mutex(__unused aio_workq_entry *entryp)
296{
297	return &aio_entry_mtx;
298}
299
300static void
301aio_workq_init(aio_workq_t wq)
302{
303	TAILQ_INIT(&wq->aioq_entries);
304	wq->aioq_count = 0;
305	lck_mtx_init(&wq->aioq_mtx, aio_queue_lock_grp, aio_lock_attr);
306	wq->aioq_waitq = wait_queue_alloc(SYNC_POLICY_FIFO);
307}
308
309
310/*
311 * Can be passed a queue which is locked spin.
312 */
313static void
314aio_workq_remove_entry_locked(aio_workq_t queue, aio_workq_entry *entryp)
315{
316	ASSERT_AIO_WORKQ_LOCK_OWNED(queue);
317
318	if (entryp->aio_workq_link.tqe_prev == NULL) {
319		panic("Trying to remove an entry from a work queue, but it is not on a queue\n");
320	}
321
322	TAILQ_REMOVE(&queue->aioq_entries, entryp, aio_workq_link);
323	queue->aioq_count--;
324	entryp->aio_workq_link.tqe_prev = NULL; /* Not on a workq */
325
326	if (queue->aioq_count  < 0) {
327		panic("Negative count on a queue.\n");
328	}
329}
330
331static void
332aio_workq_add_entry_locked(aio_workq_t queue, aio_workq_entry *entryp)
333{
334	ASSERT_AIO_WORKQ_LOCK_OWNED(queue);
335
336	TAILQ_INSERT_TAIL(&queue->aioq_entries, entryp, aio_workq_link);
337	if (queue->aioq_count  < 0) {
338		panic("Negative count on a queue.\n");
339	}
340	queue->aioq_count++;
341}
342
343static void
344aio_proc_lock(proc_t procp)
345{
346	lck_mtx_lock(aio_proc_mutex(procp));
347}
348
349static void
350aio_proc_lock_spin(proc_t procp)
351{
352	lck_mtx_lock_spin(aio_proc_mutex(procp));
353}
354
355static void
356aio_proc_move_done_locked(proc_t procp, aio_workq_entry *entryp)
357{
358	ASSERT_AIO_PROC_LOCK_OWNED(procp);
359
360	TAILQ_REMOVE(&procp->p_aio_activeq, entryp, aio_proc_link );
361	TAILQ_INSERT_TAIL( &procp->p_aio_doneq, entryp, aio_proc_link);
362	procp->p_aio_active_count--;
363	OSIncrementAtomic(&aio_anchor.aio_done_count);
364}
365
366static void
367aio_proc_remove_done_locked(proc_t procp, aio_workq_entry *entryp)
368{
369	TAILQ_REMOVE(&procp->p_aio_doneq, entryp, aio_proc_link);
370	OSDecrementAtomic(&aio_anchor.aio_done_count);
371	aio_decrement_total_count();
372	procp->p_aio_total_count--;
373}
374
375static void
376aio_proc_unlock(proc_t procp)
377{
378	lck_mtx_unlock(aio_proc_mutex(procp));
379}
380
381static lck_mtx_t*
382aio_proc_mutex(proc_t procp)
383{
384	return &procp->p_mlock;
385}
386
387static void
388aio_entry_ref_locked(aio_workq_entry *entryp)
389{
390	ASSERT_AIO_ENTRY_LOCK_OWNED(entryp);
391
392	if (entryp->aio_refcount < 0) {
393		panic("AIO workq entry with a negative refcount.\n");
394	}
395	entryp->aio_refcount++;
396}
397
398
399/* Return 1 if you've freed it */
400static void
401aio_entry_unref_locked(aio_workq_entry *entryp)
402{
403	ASSERT_AIO_ENTRY_LOCK_OWNED(entryp);
404
405	entryp->aio_refcount--;
406	if (entryp->aio_refcount < 0) {
407		panic("AIO workq entry with a negative refcount.\n");
408	}
409}
410
411static void
412aio_entry_ref(aio_workq_entry *entryp)
413{
414	aio_entry_lock_spin(entryp);
415	aio_entry_ref_locked(entryp);
416	aio_entry_unlock(entryp);
417}
418static void
419aio_entry_unref(aio_workq_entry *entryp)
420{
421	aio_entry_lock_spin(entryp);
422	aio_entry_unref_locked(entryp);
423
424	if ((entryp->aio_refcount == 0) && ((entryp->flags & AIO_DO_FREE) != 0)) {
425		aio_entry_unlock(entryp);
426		aio_free_request(entryp);
427	} else {
428		aio_entry_unlock(entryp);
429	}
430
431	return;
432}
433
434static void
435aio_entry_update_for_cancel(aio_workq_entry *entryp, boolean_t cancelled, int wait_for_completion, boolean_t disable_notification)
436{
437	aio_entry_lock_spin(entryp);
438
439	if (cancelled) {
440		aio_entry_ref_locked(entryp);
441		entryp->errorval = ECANCELED;
442		entryp->returnval = -1;
443	}
444
445	if ( wait_for_completion ) {
446		entryp->flags |= wait_for_completion; /* flag for special completion processing */
447	}
448
449	if ( disable_notification ) {
450		entryp->flags |= AIO_DISABLE; /* Don't want a signal */
451	}
452
453	aio_entry_unlock(entryp);
454}
455
456static int
457aio_entry_try_workq_remove(aio_workq_entry *entryp)
458{
459	/* Can only be cancelled if it's still on a work queue */
460	if (entryp->aio_workq_link.tqe_prev != NULL) {
461		aio_workq_t queue;
462
463		/* Will have to check again under the lock */
464		queue = aio_entry_workq(entryp);
465		aio_workq_lock_spin(queue);
466		if (entryp->aio_workq_link.tqe_prev != NULL) {
467			aio_workq_remove_entry_locked(queue, entryp);
468			aio_workq_unlock(queue);
469			return 1;
470		}  else {
471			aio_workq_unlock(queue);
472		}
473	}
474
475	return 0;
476}
477
478static void
479aio_workq_lock_spin(aio_workq_t wq)
480{
481	lck_mtx_lock_spin(aio_workq_mutex(wq));
482}
483
484static void
485aio_workq_unlock(aio_workq_t wq)
486{
487	lck_mtx_unlock(aio_workq_mutex(wq));
488}
489
490static lck_mtx_t*
491aio_workq_mutex(aio_workq_t wq)
492{
493	return &wq->aioq_mtx;
494}
495
496/*
497 * aio_cancel - attempt to cancel one or more async IO requests currently
498 * outstanding against file descriptor uap->fd.  If uap->aiocbp is not
499 * NULL then only one specific IO is cancelled (if possible).  If uap->aiocbp
500 * is NULL then all outstanding async IO request for the given file
501 * descriptor are cancelled (if possible).
502 */
503int
504aio_cancel(proc_t p, struct aio_cancel_args *uap, int *retval )
505{
506	struct user_aiocb		my_aiocb;
507	int							result;
508
509	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_cancel)) | DBG_FUNC_START,
510		     	  (int)p, (int)uap->aiocbp, 0, 0, 0 );
511
512	/* quick check to see if there are any async IO requests queued up */
513	if (aio_get_all_queues_count() < 1) {
514		result = 0;
515		*retval = AIO_ALLDONE;
516		goto ExitRoutine;
517	}
518
519	*retval = -1;
520	if ( uap->aiocbp != USER_ADDR_NULL ) {
521		if ( proc_is64bit(p) ) {
522			struct user64_aiocb aiocb64;
523
524			result = copyin( uap->aiocbp, &aiocb64, sizeof(aiocb64) );
525			if (result == 0 )
526				do_munge_aiocb_user64_to_user(&aiocb64, &my_aiocb);
527
528		} else {
529			struct user32_aiocb aiocb32;
530
531			result = copyin( uap->aiocbp, &aiocb32, sizeof(aiocb32) );
532			if ( result == 0 )
533				do_munge_aiocb_user32_to_user( &aiocb32, &my_aiocb );
534		}
535
536		if ( result != 0 ) {
537			result = EAGAIN;
538			goto ExitRoutine;
539		}
540
541		/* NOTE - POSIX standard says a mismatch between the file */
542		/* descriptor passed in and the file descriptor embedded in */
543		/* the aiocb causes unspecified results.  We return EBADF in */
544		/* that situation.  */
545		if ( uap->fd != my_aiocb.aio_fildes ) {
546			result = EBADF;
547			goto ExitRoutine;
548		}
549	}
550
551	aio_proc_lock(p);
552	result = do_aio_cancel_locked( p, uap->fd, uap->aiocbp, 0, FALSE );
553	ASSERT_AIO_PROC_LOCK_OWNED(p);
554	aio_proc_unlock(p);
555
556	if ( result != -1 ) {
557		*retval = result;
558		result = 0;
559		goto ExitRoutine;
560	}
561
562	result = EBADF;
563
564ExitRoutine:
565	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_cancel)) | DBG_FUNC_END,
566		     	  (int)p, (int)uap->aiocbp, result, 0, 0 );
567
568	return( result );
569
570} /* aio_cancel */
571
572
573/*
574 * _aio_close - internal function used to clean up async IO requests for
575 * a file descriptor that is closing.
576 * THIS MAY BLOCK.
577 */
578__private_extern__ void
579_aio_close(proc_t p, int fd )
580{
581	int			error;
582
583	/* quick check to see if there are any async IO requests queued up */
584	if (aio_get_all_queues_count() < 1) {
585		return;
586	}
587
588	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_close)) | DBG_FUNC_START,
589		     	  (int)p, fd, 0, 0, 0 );
590
591	/* cancel all async IO requests on our todo queues for this file descriptor */
592	aio_proc_lock(p);
593	error = do_aio_cancel_locked( p, fd, 0, AIO_CLOSE_WAIT, FALSE );
594	ASSERT_AIO_PROC_LOCK_OWNED(p);
595	if ( error == AIO_NOTCANCELED ) {
596		/*
597		 * AIO_NOTCANCELED is returned when we find an aio request for this process
598		 * and file descriptor on the active async IO queue.  Active requests cannot
599		 * be cancelled so we must wait for them to complete.  We will get a special
600		 * wake up call on our channel used to sleep for ALL active requests to
601		 * complete.  This sleep channel (proc.AIO_CLEANUP_SLEEP_CHAN) is only used
602		 * when we must wait for all active aio requests.
603		 */
604
605		KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_close_sleep)) | DBG_FUNC_NONE,
606		     	 	  (int)p, fd, 0, 0, 0 );
607
608		while (aio_proc_active_requests_for_file(p, fd) > 0) {
609			msleep(&p->AIO_CLEANUP_SLEEP_CHAN, aio_proc_mutex(p), PRIBIO | PDROP, "aio_close", 0 );
610		}
611
612	} else {
613		aio_proc_unlock(p);
614	}
615
616
617	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_close)) | DBG_FUNC_END,
618		     	  (int)p, fd, 0, 0, 0 );
619
620	return;
621
622} /* _aio_close */
623
624
625/*
626 * aio_error - return the error status associated with the async IO
627 * request referred to by uap->aiocbp.  The error status is the errno
628 * value that would be set by the corresponding IO request (read, wrtie,
629 * fdatasync, or sync).
630 */
631int
632aio_error(proc_t p, struct aio_error_args *uap, int *retval )
633{
634	aio_workq_entry		 		*entryp;
635	int							error;
636
637	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_error)) | DBG_FUNC_START,
638		     	  (int)p, (int)uap->aiocbp, 0, 0, 0 );
639
640	/* see if there are any aios to check */
641	if (aio_get_all_queues_count() < 1) {
642		return EINVAL;
643	}
644
645	aio_proc_lock(p);
646
647	/* look for a match on our queue of async IO requests that have completed */
648	TAILQ_FOREACH( entryp, &p->p_aio_doneq, aio_proc_link) {
649		if ( entryp->uaiocbp == uap->aiocbp ) {
650			ASSERT_AIO_FROM_PROC(entryp, p);
651
652			aio_entry_lock_spin(entryp);
653			*retval = entryp->errorval;
654			error = 0;
655			aio_entry_unlock(entryp);
656			KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_error_val)) | DBG_FUNC_NONE,
657		     	 		   (int)p, (int)uap->aiocbp, *retval, 0, 0 );
658			goto ExitRoutine;
659		}
660	}
661
662	/* look for a match on our queue of active async IO requests */
663	TAILQ_FOREACH( entryp, &p->p_aio_activeq, aio_proc_link) {
664		if ( entryp->uaiocbp == uap->aiocbp ) {
665			ASSERT_AIO_FROM_PROC(entryp, p);
666			*retval = EINPROGRESS;
667			error = 0;
668			KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_error_activeq)) | DBG_FUNC_NONE,
669		     	 		   (int)p, (int)uap->aiocbp, *retval, 0, 0 );
670			goto ExitRoutine;
671		}
672	}
673
674	error = EINVAL;
675
676ExitRoutine:
677	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_error)) | DBG_FUNC_END,
678		     	  (int)p, (int)uap->aiocbp, error, 0, 0 );
679	aio_proc_unlock(p);
680
681	return( error );
682
683} /* aio_error */
684
685
686/*
687 * aio_fsync - asynchronously force all IO operations associated
688 * with the file indicated by the file descriptor (uap->aiocbp->aio_fildes) and
689 * queued at the time of the call to the synchronized completion state.
690 * NOTE - we do not support op O_DSYNC at this point since we do not support the
691 * fdatasync() call.
692 */
693int
694aio_fsync(proc_t p, struct aio_fsync_args *uap, int *retval )
695{
696	int			error;
697	int			fsync_kind;
698
699	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_fsync)) | DBG_FUNC_START,
700		     	  (int)p, (int)uap->aiocbp, uap->op, 0, 0 );
701
702	*retval = 0;
703	/* 0 := O_SYNC for binary backward compatibility with Panther */
704	if (uap->op == O_SYNC || uap->op == 0)
705		fsync_kind = AIO_FSYNC;
706	else if ( uap->op == O_DSYNC )
707		fsync_kind = AIO_DSYNC;
708	else {
709		*retval = -1;
710		error = EINVAL;
711		goto ExitRoutine;
712	}
713
714	error = aio_queue_async_request( p, uap->aiocbp, fsync_kind );
715	if ( error != 0 )
716		*retval = -1;
717
718ExitRoutine:
719	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_fsync)) | DBG_FUNC_END,
720		     	  (int)p, (int)uap->aiocbp, error, 0, 0 );
721
722	return( error );
723
724} /* aio_fsync */
725
726
727/* aio_read - asynchronously read uap->aiocbp->aio_nbytes bytes from the
728 * file descriptor (uap->aiocbp->aio_fildes) into the buffer
729 * (uap->aiocbp->aio_buf).
730 */
731int
732aio_read(proc_t p, struct aio_read_args *uap, int *retval )
733{
734	int			error;
735
736	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_read)) | DBG_FUNC_START,
737		     	  (int)p, (int)uap->aiocbp, 0, 0, 0 );
738
739	*retval = 0;
740
741	error = aio_queue_async_request( p, uap->aiocbp, AIO_READ );
742	if ( error != 0 )
743		*retval = -1;
744
745	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_read)) | DBG_FUNC_END,
746		     	  (int)p, (int)uap->aiocbp, error, 0, 0 );
747
748	return( error );
749
750} /* aio_read */
751
752
753/*
754 * aio_return - return the return status associated with the async IO
755 * request referred to by uap->aiocbp.  The return status is the value
756 * that would be returned by corresponding IO request (read, write,
757 * fdatasync, or sync).  This is where we release kernel resources
758 * held for async IO call associated with the given aiocb pointer.
759 */
760int
761aio_return(proc_t p, struct aio_return_args *uap, user_ssize_t *retval )
762{
763	aio_workq_entry		 		*entryp;
764	int							error;
765	boolean_t					proc_lock_held = FALSE;
766
767	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_return)) | DBG_FUNC_START,
768		     	  (int)p, (int)uap->aiocbp, 0, 0, 0 );
769
770	/* See if there are any entries to check */
771	if (aio_get_all_queues_count() < 1) {
772		error = EINVAL;
773		goto ExitRoutine;
774	}
775
776	aio_proc_lock(p);
777	proc_lock_held = TRUE;
778	*retval = 0;
779
780	/* look for a match on our queue of async IO requests that have completed */
781	TAILQ_FOREACH( entryp, &p->p_aio_doneq, aio_proc_link) {
782		ASSERT_AIO_FROM_PROC(entryp, p);
783		if ( entryp->uaiocbp == uap->aiocbp ) {
784			/* Done and valid for aio_return(), pull it off the list */
785			aio_proc_remove_done_locked(p, entryp);
786
787			/* Drop the proc lock, but keep the entry locked */
788			aio_entry_lock(entryp);
789			aio_proc_unlock(p);
790			proc_lock_held = FALSE;
791
792			*retval = entryp->returnval;
793			error = 0;
794
795			/* No references and off all lists, safe to free */
796			if (entryp->aio_refcount == 0) {
797				aio_entry_unlock(entryp);
798				aio_free_request(entryp);
799			}
800			else {
801				/* Whoever has the refcount will have to free it */
802				entryp->flags |= AIO_DO_FREE;
803				aio_entry_unlock(entryp);
804			}
805
806
807			KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_return_val)) | DBG_FUNC_NONE,
808		     	 		   (int)p, (int)uap->aiocbp, *retval, 0, 0 );
809			goto ExitRoutine;
810		}
811	}
812
813	/* look for a match on our queue of active async IO requests */
814	TAILQ_FOREACH( entryp, &p->p_aio_activeq, aio_proc_link) {
815		ASSERT_AIO_FROM_PROC(entryp, p);
816		if ( entryp->uaiocbp == uap->aiocbp ) {
817			error = EINPROGRESS;
818			KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_return_activeq)) | DBG_FUNC_NONE,
819		     	 		   (int)p, (int)uap->aiocbp, *retval, 0, 0 );
820			goto ExitRoutine;
821		}
822	}
823
824	error = EINVAL;
825
826ExitRoutine:
827	if (proc_lock_held)
828		aio_proc_unlock(p);
829	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_return)) | DBG_FUNC_END,
830		     	  (int)p, (int)uap->aiocbp, error, 0, 0 );
831
832	return( error );
833
834} /* aio_return */
835
836
837/*
838 * _aio_exec - internal function used to clean up async IO requests for
839 * a process that is going away due to exec().  We cancel any async IOs
840 * we can and wait for those already active.  We also disable signaling
841 * for cancelled or active aio requests that complete.
842 * This routine MAY block!
843 */
844__private_extern__ void
845_aio_exec(proc_t p )
846{
847
848	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_exec)) | DBG_FUNC_START,
849		     	  (int)p, 0, 0, 0, 0 );
850
851	_aio_exit( p );
852
853	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_exec)) | DBG_FUNC_END,
854		     	  (int)p, 0, 0, 0, 0 );
855
856	return;
857
858} /* _aio_exec */
859
860
861/*
862 * _aio_exit - internal function used to clean up async IO requests for
863 * a process that is terminating (via exit() or exec() ).  We cancel any async IOs
864 * we can and wait for those already active.  We also disable signaling
865 * for cancelled or active aio requests that complete.  This routine MAY block!
866 */
867__private_extern__ void
868_aio_exit(proc_t p )
869{
870	int						error;
871	aio_workq_entry 		*entryp;
872
873
874	/* quick check to see if there are any async IO requests queued up */
875	if (aio_get_all_queues_count() < 1) {
876		return;
877	}
878
879	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_exit)) | DBG_FUNC_START,
880		     	  (int)p, 0, 0, 0, 0 );
881
882	aio_proc_lock(p);
883
884	/*
885	 * cancel async IO requests on the todo work queue and wait for those
886	 * already active to complete.
887	 */
888	error = do_aio_cancel_locked( p, 0, 0, AIO_EXIT_WAIT, TRUE );
889	ASSERT_AIO_PROC_LOCK_OWNED(p);
890	if ( error == AIO_NOTCANCELED ) {
891		/*
892		 * AIO_NOTCANCELED is returned when we find an aio request for this process
893		 * on the active async IO queue.  Active requests cannot be cancelled so we
894		 * must wait for them to complete.  We will get a special wake up call on
895		 * our channel used to sleep for ALL active requests to complete.  This sleep
896		 * channel (proc.AIO_CLEANUP_SLEEP_CHAN) is only used when we must wait for all
897		 * active aio requests.
898		 */
899
900		KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_exit_sleep)) | DBG_FUNC_NONE,
901		     	 	  (int)p, 0, 0, 0, 0 );
902
903		while (p->p_aio_active_count != 0) {
904			msleep(&p->AIO_CLEANUP_SLEEP_CHAN, aio_proc_mutex(p), PRIBIO, "aio_exit", 0 );
905		}
906	}
907
908	if (p->p_aio_active_count != 0) {
909		panic("Exiting process has %d active AIOs after cancellation has completed.\n", p->p_aio_active_count);
910	}
911
912	/* release all aio resources used by this process */
913	entryp = TAILQ_FIRST( &p->p_aio_doneq );
914	while ( entryp != NULL ) {
915		ASSERT_AIO_FROM_PROC(entryp, p);
916		aio_workq_entry		 	*next_entryp;
917
918		next_entryp = TAILQ_NEXT( entryp, aio_proc_link);
919		aio_proc_remove_done_locked(p, entryp);
920
921		/* we cannot free requests that are still completing */
922		aio_entry_lock_spin(entryp);
923		if (entryp->aio_refcount == 0) {
924			aio_proc_unlock(p);
925			aio_entry_unlock(entryp);
926			aio_free_request(entryp);
927
928			/* need to start over since aio_doneq may have been */
929			/* changed while we were away.  */
930			aio_proc_lock(p);
931			entryp = TAILQ_FIRST( &p->p_aio_doneq );
932			continue;
933		}
934		else {
935			/* whoever has the reference will have to do the free */
936			entryp->flags |= AIO_DO_FREE;
937		}
938
939		aio_entry_unlock(entryp);
940		entryp = next_entryp;
941	}
942
943	aio_proc_unlock(p);
944
945	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_exit)) | DBG_FUNC_END,
946		     	  (int)p, 0, 0, 0, 0 );
947	return;
948
949} /* _aio_exit */
950
951
952static boolean_t
953should_cancel(aio_workq_entry *entryp, user_addr_t aiocbp, int fd)
954{
955	if ( (aiocbp == USER_ADDR_NULL && fd == 0) ||
956			(aiocbp != USER_ADDR_NULL && entryp->uaiocbp == aiocbp) ||
957			(aiocbp == USER_ADDR_NULL && fd == entryp->aiocb.aio_fildes) ) {
958		return TRUE;
959	}
960
961	return FALSE;
962}
963
964/*
965 * do_aio_cancel_locked - cancel async IO requests (if possible).  We get called by
966 * aio_cancel, close, and at exit.
967 * There are three modes of operation: 1) cancel all async IOs for a process -
968 * fd is 0 and aiocbp is NULL 2) cancel all async IOs for file descriptor - fd
969 * is > 0 and aiocbp is NULL 3) cancel one async IO associated with the given
970 * aiocbp.
971 * Returns -1 if no matches were found, AIO_CANCELED when we cancelled all
972 * target async IO requests, AIO_NOTCANCELED if we could not cancel all
973 * target async IO requests, and AIO_ALLDONE if all target async IO requests
974 * were already complete.
975 * WARNING - do not deference aiocbp in this routine, it may point to user
976 * land data that has not been copied in (when called from aio_cancel() )
977 *
978 * Called with proc locked, and returns the same way.
979 */
980static int
981do_aio_cancel_locked(proc_t p, int fd, user_addr_t aiocbp,
982	int wait_for_completion, boolean_t disable_notification )
983{
984	ASSERT_AIO_PROC_LOCK_OWNED(p);
985
986	aio_workq_entry		 	*entryp;
987	int						result;
988
989	result = -1;
990
991	/* look for a match on our queue of async todo work. */
992	entryp = TAILQ_FIRST(&p->p_aio_activeq);
993	while ( entryp != NULL ) {
994		ASSERT_AIO_FROM_PROC(entryp, p);
995		aio_workq_entry		 	*next_entryp;
996
997		next_entryp = TAILQ_NEXT( entryp, aio_proc_link);
998		if (!should_cancel(entryp, aiocbp, fd)) {
999			entryp = next_entryp;
1000			continue;
1001		}
1002
1003		/* Can only be cancelled if it's still on a work queue */
1004		if (aio_entry_try_workq_remove(entryp) != 0) {
1005			/* Have removed from workq. Update entry state and take a ref */
1006			aio_entry_update_for_cancel(entryp, TRUE, 0, disable_notification);
1007
1008			/* Put on the proc done queue and update counts, then unlock the proc */
1009			aio_proc_move_done_locked(p, entryp);
1010			aio_proc_unlock(p);
1011
1012			/* Now it's officially cancelled.  Do the completion */
1013			result = AIO_CANCELED;
1014			KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_cancel_async_workq)) | DBG_FUNC_NONE,
1015					(int)entryp->procp, (int)entryp->uaiocbp, fd, 0, 0 );
1016			do_aio_completion(entryp);
1017
1018			/* This will free if the aio_return() has already happened ... */
1019			aio_entry_unref(entryp);
1020			aio_proc_lock(p);
1021
1022			if ( aiocbp != USER_ADDR_NULL ) {
1023				return( result );
1024			}
1025
1026			/*
1027			 * Restart from the head of the proc active queue since it
1028			 * may have been changed while we were away doing completion
1029			 * processing.
1030			 *
1031			 * Note that if we found an uncancellable AIO before, we will
1032			 * either find it again or discover that it's been completed,
1033			 * so resetting the result will not cause us to return success
1034			 * despite outstanding AIOs.
1035			 */
1036			entryp = TAILQ_FIRST(&p->p_aio_activeq);
1037			result = -1; /* As if beginning anew */
1038		} else {
1039			/*
1040			 * It's been taken off the active queue already, i.e. is in flight.
1041			 * All we can do is ask for notification.
1042			 */
1043			result = AIO_NOTCANCELED;
1044
1045			KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_cancel_activeq)) | DBG_FUNC_NONE,
1046					(int)entryp->procp, (int)entryp->uaiocbp, fd, 0, 0 );
1047
1048			/* Mark for waiting and such; will not take a ref if "cancelled" arg is FALSE */
1049			aio_entry_update_for_cancel(entryp, FALSE, wait_for_completion, disable_notification);
1050
1051			if ( aiocbp != USER_ADDR_NULL ) {
1052				return( result );
1053			}
1054			entryp = next_entryp;
1055		}
1056	} /* while... */
1057
1058	/*
1059	 * if we didn't find any matches on the todo or active queues then look for a
1060	 * match on our queue of async IO requests that have completed and if found
1061	 * return AIO_ALLDONE result.
1062	 *
1063	 * Proc AIO lock is still held.
1064	 */
1065	if ( result == -1 ) {
1066		TAILQ_FOREACH(entryp, &p->p_aio_doneq, aio_proc_link) {
1067			ASSERT_AIO_FROM_PROC(entryp, p);
1068			if (should_cancel(entryp, aiocbp, fd)) {
1069				result = AIO_ALLDONE;
1070				KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_cancel_doneq)) | DBG_FUNC_NONE,
1071						(int)entryp->procp, (int)entryp->uaiocbp, fd, 0, 0 );
1072
1073				if ( aiocbp != USER_ADDR_NULL ) {
1074					return( result );
1075				}
1076			}
1077		}
1078	}
1079
1080	return( result );
1081
1082}
1083 /* do_aio_cancel_locked */
1084
1085
1086/*
1087 * aio_suspend - suspend the calling thread until at least one of the async
1088 * IO operations referenced by uap->aiocblist has completed, until a signal
1089 * interrupts the function, or uap->timeoutp time interval (optional) has
1090 * passed.
1091 * Returns 0 if one or more async IOs have completed else -1 and errno is
1092 * set appropriately - EAGAIN if timeout elapses or EINTR if an interrupt
1093 * woke us up.
1094 */
1095int
1096aio_suspend(proc_t p, struct aio_suspend_args *uap, int *retval )
1097{
1098	__pthread_testcancel(1);
1099	return(aio_suspend_nocancel(p, (struct aio_suspend_nocancel_args *)uap, retval));
1100}
1101
1102
1103int
1104aio_suspend_nocancel(proc_t p, struct aio_suspend_nocancel_args *uap, int *retval )
1105{
1106	int					error;
1107	int					i, count;
1108	uint64_t			abstime;
1109	struct user_timespec ts;
1110	aio_workq_entry 	*entryp;
1111	user_addr_t			*aiocbpp;
1112
1113	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_suspend)) | DBG_FUNC_START,
1114		     	  (int)p, uap->nent, 0, 0, 0 );
1115
1116	*retval = -1;
1117	abstime = 0;
1118	aiocbpp = NULL;
1119
1120	count = aio_get_all_queues_count( );
1121	if ( count < 1 ) {
1122		error = EINVAL;
1123		goto ExitThisRoutine;
1124	}
1125
1126	if ( uap->nent < 1 || uap->nent > aio_max_requests_per_process ) {
1127		error = EINVAL;
1128		goto ExitThisRoutine;
1129	}
1130
1131	if ( uap->timeoutp != USER_ADDR_NULL ) {
1132		if ( proc_is64bit(p) ) {
1133			struct user64_timespec temp;
1134			error = copyin( uap->timeoutp, &temp, sizeof(temp) );
1135			if ( error == 0 ) {
1136				ts.tv_sec = temp.tv_sec;
1137				ts.tv_nsec = temp.tv_nsec;
1138			}
1139		}
1140		else {
1141			struct user32_timespec temp;
1142			error = copyin( uap->timeoutp, &temp, sizeof(temp) );
1143			if ( error == 0 ) {
1144				ts.tv_sec = temp.tv_sec;
1145				ts.tv_nsec = temp.tv_nsec;
1146			}
1147		}
1148		if ( error != 0 ) {
1149			error = EAGAIN;
1150			goto ExitThisRoutine;
1151		}
1152
1153		if ( ts.tv_sec < 0 || ts.tv_nsec < 0 || ts.tv_nsec >= 1000000000 ) {
1154			error = EINVAL;
1155			goto ExitThisRoutine;
1156		}
1157
1158		nanoseconds_to_absolutetime( (uint64_t)ts.tv_sec * NSEC_PER_SEC + ts.tv_nsec,
1159									 &abstime );
1160		clock_absolutetime_interval_to_deadline( abstime, &abstime );
1161	}
1162
1163	aiocbpp = aio_copy_in_list(p, uap->aiocblist, uap->nent);
1164	if ( aiocbpp == NULL ) {
1165		error = EAGAIN;
1166		goto ExitThisRoutine;
1167	}
1168
1169	/* check list of aio requests to see if any have completed */
1170check_for_our_aiocbp:
1171	aio_proc_lock_spin(p);
1172	for ( i = 0; i < uap->nent; i++ ) {
1173		user_addr_t	aiocbp;
1174
1175		/* NULL elements are legal so check for 'em */
1176		aiocbp = *(aiocbpp + i);
1177		if ( aiocbp == USER_ADDR_NULL )
1178			continue;
1179
1180		/* return immediately if any aio request in the list is done */
1181		TAILQ_FOREACH( entryp, &p->p_aio_doneq, aio_proc_link) {
1182			ASSERT_AIO_FROM_PROC(entryp, p);
1183			if ( entryp->uaiocbp == aiocbp ) {
1184				aio_proc_unlock(p);
1185				*retval = 0;
1186				error = 0;
1187				goto ExitThisRoutine;
1188			}
1189		}
1190	} /* for ( ; i < uap->nent; ) */
1191
1192	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_suspend_sleep)) | DBG_FUNC_NONE,
1193		     	  (int)p, uap->nent, 0, 0, 0 );
1194
1195	/*
1196	 * wait for an async IO to complete or a signal fires or timeout expires.
1197	 * we return EAGAIN (35) for timeout expiration and EINTR (4) when a signal
1198	 * interrupts us.  If an async IO completes before a signal fires or our
1199	 * timeout expires, we get a wakeup call from aio_work_thread().
1200	 */
1201
1202	error = msleep1(&p->AIO_SUSPEND_SLEEP_CHAN, aio_proc_mutex(p), PCATCH | PWAIT | PDROP, "aio_suspend", abstime); /* XXX better priority? */
1203	if ( error == 0 ) {
1204		/*
1205		 * got our wakeup call from aio_work_thread().
1206		 * Since we can get a wakeup on this channel from another thread in the
1207		 * same process we head back up to make sure this is for the correct aiocbp.
1208		 * If it is the correct aiocbp we will return from where we do the check
1209		 * (see entryp->uaiocbp == aiocbp after check_for_our_aiocbp label)
1210		 * else we will fall out and just sleep again.
1211		 */
1212		goto check_for_our_aiocbp;
1213	}
1214	else if ( error == EWOULDBLOCK ) {
1215		/* our timeout expired */
1216		error = EAGAIN;
1217	}
1218	else {
1219		/* we were interrupted */
1220		error = EINTR;
1221	}
1222
1223ExitThisRoutine:
1224	if ( aiocbpp != NULL )
1225		FREE( aiocbpp, M_TEMP );
1226
1227	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_suspend)) | DBG_FUNC_END,
1228		     	  (int)p, uap->nent, error, 0, 0 );
1229
1230	return( error );
1231
1232} /* aio_suspend */
1233
1234
1235/* aio_write - asynchronously write uap->aiocbp->aio_nbytes bytes to the
1236 * file descriptor (uap->aiocbp->aio_fildes) from the buffer
1237 * (uap->aiocbp->aio_buf).
1238 */
1239
1240int
1241aio_write(proc_t p, struct aio_write_args *uap, int *retval )
1242{
1243	int			error;
1244
1245	*retval = 0;
1246
1247	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_write)) | DBG_FUNC_START,
1248		     	  (int)p, (int)uap->aiocbp, 0, 0, 0 );
1249
1250	error = aio_queue_async_request( p, uap->aiocbp, AIO_WRITE );
1251	if ( error != 0 )
1252		*retval = -1;
1253
1254	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_write)) | DBG_FUNC_END,
1255		     	  (int)p, (int)uap->aiocbp, error, 0, 0 );
1256
1257	return( error );
1258
1259} /* aio_write */
1260
1261
1262static user_addr_t *
1263aio_copy_in_list(proc_t procp, user_addr_t aiocblist, int nent)
1264{
1265	user_addr_t	*aiocbpp;
1266	int		i, result;
1267
1268	/* we reserve enough space for largest possible pointer size */
1269	MALLOC( aiocbpp, user_addr_t *, (nent * sizeof(user_addr_t)), M_TEMP, M_WAITOK );
1270	if ( aiocbpp == NULL )
1271		goto err;
1272
1273	/* copyin our aiocb pointers from list */
1274	result = copyin( aiocblist, aiocbpp,
1275			proc_is64bit(procp) ? (nent * sizeof(user64_addr_t))
1276					    : (nent * sizeof(user32_addr_t)) );
1277	if ( result) {
1278		FREE( aiocbpp, M_TEMP );
1279		aiocbpp = NULL;
1280		goto err;
1281	}
1282
1283	/*
1284	 * We depend on a list of user_addr_t's so we need to
1285	 * munge and expand when these pointers came from a
1286	 * 32-bit process
1287	 */
1288	if ( !proc_is64bit(procp) ) {
1289		/* copy from last to first to deal with overlap */
1290		user32_addr_t *my_ptrp = ((user32_addr_t *)aiocbpp) + (nent - 1);
1291		user_addr_t *my_addrp = aiocbpp + (nent - 1);
1292
1293		for (i = 0; i < nent; i++, my_ptrp--, my_addrp--) {
1294			*my_addrp = (user_addr_t) (*my_ptrp);
1295		}
1296	}
1297
1298err:
1299	return (aiocbpp);
1300}
1301
1302
1303static int
1304aio_copy_in_sigev(proc_t procp, user_addr_t sigp, struct user_sigevent *sigev)
1305{
1306	int	result = 0;
1307
1308	if (sigp == USER_ADDR_NULL)
1309		goto out;
1310
1311	/*
1312	 * We need to munge aio_sigevent since it contains pointers.
1313	 * Since we do not know if sigev_value is an int or a ptr we do
1314	 * NOT cast the ptr to a user_addr_t.   This means if we send
1315	 * this info back to user space we need to remember sigev_value
1316	 * was not expanded for the 32-bit case.
1317	 *
1318	 * Notes:	 This does NOT affect us since we don't support
1319	 *		sigev_value yet in the aio context.
1320	 */
1321	if ( proc_is64bit(procp) ) {
1322		struct user64_sigevent sigevent64;
1323
1324		result = copyin( sigp, &sigevent64, sizeof(sigevent64) );
1325		if ( result == 0 ) {
1326			sigev->sigev_notify = sigevent64.sigev_notify;
1327			sigev->sigev_signo = sigevent64.sigev_signo;
1328			sigev->sigev_value.size_equivalent.sival_int = sigevent64.sigev_value.size_equivalent.sival_int;
1329			sigev->sigev_notify_function = sigevent64.sigev_notify_function;
1330			sigev->sigev_notify_attributes = sigevent64.sigev_notify_attributes;
1331		}
1332
1333	} else {
1334		struct user32_sigevent sigevent32;
1335
1336		result = copyin( sigp, &sigevent32, sizeof(sigevent32) );
1337		if ( result == 0 ) {
1338			sigev->sigev_notify = sigevent32.sigev_notify;
1339			sigev->sigev_signo = sigevent32.sigev_signo;
1340			sigev->sigev_value.size_equivalent.sival_int = sigevent32.sigev_value.sival_int;
1341			sigev->sigev_notify_function = CAST_USER_ADDR_T(sigevent32.sigev_notify_function);
1342			sigev->sigev_notify_attributes = CAST_USER_ADDR_T(sigevent32.sigev_notify_attributes);
1343		}
1344	}
1345
1346	if ( result != 0 ) {
1347		result = EAGAIN;
1348	}
1349
1350out:
1351	return (result);
1352}
1353
1354/*
1355 * aio_enqueue_work
1356 *
1357 * Queue up the entry on the aio asynchronous work queue in priority order
1358 * based on the relative priority of the request.  We calculate the relative
1359 * priority using the nice value of the caller and the value
1360 *
1361 * Parameters:	procp			Process queueing the I/O
1362 *		entryp			The work queue entry being queued
1363 *
1364 * Returns:	(void)			No failure modes
1365 *
1366 * Notes:	This function is used for both lio_listio and aio
1367 *
1368 * XXX:		At some point, we may have to consider thread priority
1369 *		rather than process priority, but we don't maintain the
1370 *		adjusted priority for threads the POSIX way.
1371 *
1372 *
1373 * Called with proc locked.
1374 */
1375static void
1376aio_enqueue_work( proc_t procp, aio_workq_entry *entryp, int proc_locked)
1377{
1378#if 0
1379	aio_workq_entry	*my_entryp;	/* used for insertion sort */
1380#endif /* 0 */
1381	aio_workq_t queue = aio_entry_workq(entryp);
1382
1383	if (proc_locked == 0) {
1384		aio_proc_lock(procp);
1385	}
1386
1387	ASSERT_AIO_PROC_LOCK_OWNED(procp);
1388
1389	/* Onto proc queue */
1390	TAILQ_INSERT_TAIL(&procp->p_aio_activeq, entryp,  aio_proc_link);
1391	procp->p_aio_active_count++;
1392	procp->p_aio_total_count++;
1393
1394	/* And work queue */
1395	aio_workq_lock_spin(queue);
1396	aio_workq_add_entry_locked(queue, entryp);
1397	wait_queue_wakeup_one(queue->aioq_waitq, queue, THREAD_AWAKENED, -1);
1398	aio_workq_unlock(queue);
1399
1400	if (proc_locked == 0) {
1401		aio_proc_unlock(procp);
1402	}
1403
1404#if 0
1405	/*
1406	 * Procedure:
1407	 *
1408	 * (1)	The nice value is in the range PRIO_MIN..PRIO_MAX [-20..20]
1409	 * (2)	The normalized nice value is in the range 0..((2 * NZERO) - 1)
1410	 *	which is [0..39], with 0 not being used.  In nice values, the
1411	 *	lower the nice value, the higher the priority.
1412	 * (3)	The normalized scheduling prioritiy is the highest nice value
1413	 *	minus the current nice value.  In I/O scheduling priority, the
1414	 *	higher the value the lower the priority, so it is the inverse
1415	 *	of the nice value (the higher the number, the higher the I/O
1416	 *	priority).
1417	 * (4)	From the normalized scheduling priority, we subtract the
1418	 *	request priority to get the request priority value number;
1419	 *	this means that requests are only capable of depressing their
1420	 *	priority relative to other requests,
1421	 */
1422	entryp->priority = (((2 * NZERO) - 1) - procp->p_nice);
1423
1424	/* only premit depressing the priority */
1425	if (entryp->aiocb.aio_reqprio < 0)
1426		entryp->aiocb.aio_reqprio = 0;
1427	if (entryp->aiocb.aio_reqprio > 0) {
1428		entryp->priority -= entryp->aiocb.aio_reqprio;
1429		if (entryp->priority < 0)
1430			entryp->priority = 0;
1431	}
1432
1433	/* Insertion sort the entry; lowest ->priority to highest */
1434	TAILQ_FOREACH(my_entryp, &aio_anchor.aio_async_workq, aio_workq_link) {
1435		if ( entryp->priority <= my_entryp->priority) {
1436			TAILQ_INSERT_BEFORE(my_entryp, entryp, aio_workq_link);
1437			break;
1438		}
1439	}
1440	if (my_entryp == NULL)
1441		TAILQ_INSERT_TAIL( &aio_anchor.aio_async_workq, entryp, aio_workq_link );
1442#endif /* 0 */
1443}
1444
1445
1446/*
1447 * lio_listio - initiate a list of IO requests.  We process the list of
1448 * aiocbs either synchronously (mode == LIO_WAIT) or asynchronously
1449 * (mode == LIO_NOWAIT).
1450 *
1451 * The caller gets error and return status for each aiocb in the list
1452 * via aio_error and aio_return.  We must keep completed requests until
1453 * released by the aio_return call.
1454 */
1455int
1456lio_listio(proc_t p, struct lio_listio_args *uap, int *retval )
1457{
1458	int				i;
1459	int				call_result;
1460	int				result;
1461	int				old_count;
1462	aio_workq_entry			**entryp_listp;
1463	user_addr_t			*aiocbpp;
1464	struct user_sigevent		aiosigev;
1465	aio_lio_context		*lio_context;
1466	boolean_t 			free_context = FALSE;
1467
1468	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_listio)) | DBG_FUNC_START,
1469		     	  (int)p, uap->nent, uap->mode, 0, 0 );
1470
1471	entryp_listp = NULL;
1472	lio_context = NULL;
1473	aiocbpp = NULL;
1474	call_result = -1;
1475	*retval = -1;
1476	if ( !(uap->mode == LIO_NOWAIT || uap->mode == LIO_WAIT) ) {
1477		call_result = EINVAL;
1478		goto ExitRoutine;
1479	}
1480
1481	if ( uap->nent < 1 || uap->nent > AIO_LISTIO_MAX ) {
1482		call_result = EINVAL;
1483		goto ExitRoutine;
1484	}
1485
1486	/*
1487	 * allocate a list of aio_workq_entry pointers that we will use
1488	 * to queue up all our requests at once while holding our lock.
1489	 */
1490	MALLOC( entryp_listp, void *, (uap->nent * sizeof(aio_workq_entry *)), M_TEMP, M_WAITOK );
1491	if ( entryp_listp == NULL ) {
1492		call_result = EAGAIN;
1493		goto ExitRoutine;
1494	}
1495
1496	MALLOC( lio_context, aio_lio_context*, sizeof(aio_lio_context), M_TEMP, M_WAITOK );
1497	if ( lio_context == NULL ) {
1498		call_result = EAGAIN;
1499		goto ExitRoutine;
1500	}
1501
1502#if DEBUG
1503	OSIncrementAtomic(&lio_contexts_alloced);
1504#endif /* DEBUG */
1505
1506	bzero(lio_context, sizeof(aio_lio_context));
1507
1508	aiocbpp = aio_copy_in_list(p, uap->aiocblist, uap->nent);
1509	if ( aiocbpp == NULL ) {
1510		call_result = EAGAIN;
1511		goto ExitRoutine;
1512	}
1513
1514	/*
1515	 * Use sigevent passed in to lio_listio for each of our calls, but
1516	 * only do completion notification after the last request completes.
1517	 */
1518	bzero(&aiosigev, sizeof(aiosigev));
1519	/* Only copy in an sigev if the user supplied one */
1520	if (uap->sigp != USER_ADDR_NULL) {
1521		call_result = aio_copy_in_sigev(p, uap->sigp, &aiosigev);
1522		if ( call_result)
1523			goto ExitRoutine;
1524	}
1525
1526	/* process list of aio requests */
1527	lio_context->io_issued = uap->nent;
1528	lio_context->io_waiter = uap->mode == LIO_WAIT ? 1 : 0; /* Should it be freed by last AIO */
1529	for ( i = 0; i < uap->nent; i++ ) {
1530		user_addr_t my_aiocbp;
1531		aio_workq_entry		 		*entryp;
1532
1533		*(entryp_listp + i) = NULL;
1534		my_aiocbp = *(aiocbpp + i);
1535
1536		/* NULL elements are legal so check for 'em */
1537		if ( my_aiocbp == USER_ADDR_NULL ) {
1538			aio_proc_lock_spin(p);
1539			lio_context->io_issued--;
1540			aio_proc_unlock(p);
1541			continue;
1542		}
1543
1544		/*
1545		 * We use lio_context to mark IO requests for delayed completion
1546		 * processing which means we wait until all IO requests in the
1547		 * group have completed before we either return to the caller
1548		 * when mode is LIO_WAIT or signal user when mode is LIO_NOWAIT.
1549		 *
1550		 * We use the address of the lio_context for this, since it is
1551		 * unique in the address space.
1552		 */
1553		result = lio_create_entry( p, my_aiocbp, lio_context, (entryp_listp + i) );
1554		if ( result != 0 && call_result == -1 )
1555			call_result = result;
1556
1557		/* NULL elements are legal so check for 'em */
1558		entryp = *(entryp_listp + i);
1559		if ( entryp == NULL ) {
1560			aio_proc_lock_spin(p);
1561			lio_context->io_issued--;
1562			aio_proc_unlock(p);
1563			continue;
1564		}
1565
1566		if ( uap->mode == LIO_NOWAIT ) {
1567			/* Set signal hander, if any */
1568			entryp->aiocb.aio_sigevent = aiosigev;
1569		} else {
1570			/* flag that this thread blocks pending completion */
1571			entryp->flags |= AIO_LIO_NOTIFY;
1572		}
1573
1574		/* check our aio limits to throttle bad or rude user land behavior */
1575		old_count = aio_increment_total_count();
1576
1577		aio_proc_lock_spin(p);
1578		if ( old_count >= aio_max_requests ||
1579			 aio_get_process_count( entryp->procp ) >= aio_max_requests_per_process ||
1580			 is_already_queued( entryp->procp, entryp->uaiocbp ) == TRUE ) {
1581
1582			lio_context->io_issued--;
1583			aio_proc_unlock(p);
1584
1585			aio_decrement_total_count();
1586
1587			if ( call_result == -1 )
1588				call_result = EAGAIN;
1589			aio_free_request(entryp);
1590			entryp_listp[i] = NULL;
1591			continue;
1592		}
1593
1594		lck_mtx_convert_spin(aio_proc_mutex(p));
1595		aio_enqueue_work(p, entryp, 1);
1596		aio_proc_unlock(p);
1597
1598		KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_work_queued)) | DBG_FUNC_NONE,
1599				  (int)p, (int)entryp->uaiocbp, 0, 0, 0 );
1600	}
1601
1602	switch(uap->mode) {
1603	case LIO_WAIT:
1604		aio_proc_lock_spin(p);
1605		while (lio_context->io_completed < lio_context->io_issued) {
1606			result = msleep(lio_context, aio_proc_mutex(p), PCATCH | PRIBIO | PSPIN, "lio_listio", 0);
1607
1608			/* If we were interrupted, fail out (even if all finished) */
1609			if (result != 0) {
1610				call_result = EINTR;
1611				lio_context->io_waiter = 0;
1612				break;
1613			}
1614		}
1615
1616		/* If all IOs have finished must free it */
1617		if (lio_context->io_completed == lio_context->io_issued) {
1618			free_context = TRUE;
1619		}
1620
1621		aio_proc_unlock(p);
1622		break;
1623
1624	case LIO_NOWAIT:
1625		break;
1626	}
1627
1628	/* call_result == -1 means we had no trouble queueing up requests */
1629	if ( call_result == -1 ) {
1630		call_result = 0;
1631		*retval = 0;
1632	}
1633
1634ExitRoutine:
1635	if ( entryp_listp != NULL )
1636		FREE( entryp_listp, M_TEMP );
1637	if ( aiocbpp != NULL )
1638		FREE( aiocbpp, M_TEMP );
1639	if ((lio_context != NULL) && ((lio_context->io_issued == 0) || (free_context == TRUE))) {
1640		free_lio_context(lio_context);
1641	}
1642
1643	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_listio)) | DBG_FUNC_END,
1644		     	  (int)p, call_result, 0, 0, 0 );
1645
1646	return( call_result );
1647
1648} /* lio_listio */
1649
1650
1651/*
1652 * aio worker thread.  this is where all the real work gets done.
1653 * we get a wake up call on sleep channel &aio_anchor.aio_async_workq
1654 * after new work is queued up.
1655 */
1656static void
1657aio_work_thread( void )
1658{
1659	aio_workq_entry		 	*entryp;
1660	int 			error;
1661	vm_map_t 		currentmap;
1662	vm_map_t 		oldmap = VM_MAP_NULL;
1663	task_t			oldaiotask = TASK_NULL;
1664	struct uthread	*uthreadp = NULL;
1665
1666	for( ;; ) {
1667		/*
1668		 * returns with the entry ref'ed.
1669		 * sleeps until work is available.
1670		 */
1671		entryp = aio_get_some_work();
1672
1673		KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_worker_thread)) | DBG_FUNC_START,
1674				(int)entryp->procp, (int)entryp->uaiocbp, entryp->flags, 0, 0 );
1675
1676		/*
1677		 * Assume the target's address space identity for the duration
1678		 * of the IO.  Note: don't need to have the entryp locked,
1679		 * because the proc and map don't change until it's freed.
1680		 */
1681		currentmap = get_task_map( (current_proc())->task );
1682		if ( currentmap != entryp->aio_map ) {
1683			uthreadp = (struct uthread *) get_bsdthread_info(current_thread());
1684			oldaiotask = uthreadp->uu_aio_task;
1685			uthreadp->uu_aio_task = entryp->procp->task;
1686			oldmap = vm_map_switch( entryp->aio_map );
1687		}
1688
1689		if ( (entryp->flags & AIO_READ) != 0 ) {
1690			error = do_aio_read( entryp );
1691		}
1692		else if ( (entryp->flags & AIO_WRITE) != 0 ) {
1693			error = do_aio_write( entryp );
1694		}
1695		else if ( (entryp->flags & (AIO_FSYNC | AIO_DSYNC)) != 0 ) {
1696			error = do_aio_fsync( entryp );
1697		}
1698		else {
1699			printf( "%s - unknown aio request - flags 0x%02X \n",
1700					__FUNCTION__, entryp->flags );
1701			error = EINVAL;
1702		}
1703
1704		/* Restore old map */
1705		if ( currentmap != entryp->aio_map ) {
1706			(void) vm_map_switch( oldmap );
1707			uthreadp->uu_aio_task = oldaiotask;
1708		}
1709
1710		KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_worker_thread)) | DBG_FUNC_END,
1711				(int)entryp->procp, (int)entryp->uaiocbp, entryp->errorval,
1712				entryp->returnval, 0 );
1713
1714
1715		/* XXX COUNTS */
1716		aio_entry_lock_spin(entryp);
1717		entryp->errorval = error;
1718		aio_entry_unlock(entryp);
1719
1720		/* we're done with the IO request so pop it off the active queue and */
1721		/* push it on the done queue */
1722		aio_proc_lock(entryp->procp);
1723		aio_proc_move_done_locked(entryp->procp, entryp);
1724		aio_proc_unlock(entryp->procp);
1725
1726		OSDecrementAtomic(&aio_anchor.aio_inflight_count);
1727
1728		/* remove our reference to the user land map. */
1729		if ( VM_MAP_NULL != entryp->aio_map ) {
1730			vm_map_t 		my_map;
1731
1732			my_map = entryp->aio_map;
1733			entryp->aio_map = VM_MAP_NULL;
1734			vm_map_deallocate( my_map );
1735		}
1736
1737		/* Provide notifications */
1738		do_aio_completion( entryp );
1739
1740		/* Will free if needed */
1741		aio_entry_unref(entryp);
1742
1743	} /* for ( ;; ) */
1744
1745	/* NOT REACHED */
1746
1747} /* aio_work_thread */
1748
1749
1750/*
1751 * aio_get_some_work - get the next async IO request that is ready to be executed.
1752 * aio_fsync complicates matters a bit since we cannot do the fsync until all async
1753 * IO requests at the time the aio_fsync call came in have completed.
1754 * NOTE - AIO_LOCK must be held by caller
1755 */
1756static aio_workq_entry *
1757aio_get_some_work( void )
1758{
1759	aio_workq_entry		 		*entryp = NULL;
1760	aio_workq_t 				queue = NULL;
1761
1762	/* Just one queue for the moment.  In the future there will be many. */
1763	queue = &aio_anchor.aio_async_workqs[0];
1764	aio_workq_lock_spin(queue);
1765	if (queue->aioq_count == 0) {
1766		goto nowork;
1767	}
1768
1769	/*
1770	 * Hold the queue lock.
1771	 *
1772	 * pop some work off the work queue and add to our active queue
1773	 * Always start with the queue lock held.
1774	 */
1775	for(;;) {
1776		/*
1777		 * Pull of of work queue.  Once it's off, it can't be cancelled,
1778		 * so we can take our ref once we drop the queue lock.
1779		 */
1780		entryp = TAILQ_FIRST(&queue->aioq_entries);
1781
1782		/*
1783		 * If there's no work or only fsyncs that need delay, go to sleep
1784		 * and then start anew from aio_work_thread
1785		 */
1786		if (entryp == NULL) {
1787			goto nowork;
1788		}
1789
1790		aio_workq_remove_entry_locked(queue, entryp);
1791
1792		aio_workq_unlock(queue);
1793
1794		/*
1795		 * Check if it's an fsync that must be delayed.  No need to lock the entry;
1796		 * that flag would have been set at initialization.
1797		 */
1798		if ( (entryp->flags & AIO_FSYNC) != 0 ) {
1799			/*
1800			 * Check for unfinished operations on the same file
1801			 * in this proc's queue.
1802			 */
1803			aio_proc_lock_spin(entryp->procp);
1804			if ( aio_delay_fsync_request( entryp ) ) {
1805				/* It needs to be delayed.  Put it back on the end of the work queue */
1806				KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_fsync_delay)) | DBG_FUNC_NONE,
1807							  (int)entryp->procp, (int)entryp->uaiocbp, 0, 0, 0 );
1808
1809				aio_proc_unlock(entryp->procp);
1810
1811				aio_workq_lock_spin(queue);
1812				aio_workq_add_entry_locked(queue, entryp);
1813				continue;
1814			}
1815			aio_proc_unlock(entryp->procp);
1816		}
1817
1818		break;
1819	}
1820
1821	aio_entry_ref(entryp);
1822
1823	OSIncrementAtomic(&aio_anchor.aio_inflight_count);
1824	return( entryp );
1825
1826nowork:
1827	/* We will wake up when someone enqueues something */
1828	wait_queue_assert_wait(queue->aioq_waitq, queue, THREAD_UNINT, 0);
1829	aio_workq_unlock(queue);
1830	thread_block( (thread_continue_t)aio_work_thread );
1831
1832	// notreached
1833	return NULL;
1834}
1835
1836/*
1837 * aio_delay_fsync_request - look to see if this aio_fsync request should be delayed.
1838 * A big, simple hammer: only send it off if it's the most recently filed IO which has
1839 * not been completed.
1840 */
1841static boolean_t
1842aio_delay_fsync_request( aio_workq_entry *entryp )
1843{
1844	if (entryp == TAILQ_FIRST(&entryp->procp->p_aio_activeq)) {
1845		return FALSE;
1846	}
1847
1848	return TRUE;
1849} /* aio_delay_fsync_request */
1850
1851static aio_workq_entry *
1852aio_create_queue_entry(proc_t procp, user_addr_t aiocbp, void *group_tag, int kindOfIO)
1853{
1854	aio_workq_entry	*entryp;
1855	int		result = 0;
1856
1857	entryp = (aio_workq_entry *) zalloc( aio_workq_zonep );
1858	if ( entryp == NULL ) {
1859		result = EAGAIN;
1860		goto error_exit;
1861	}
1862
1863	bzero( entryp, sizeof(*entryp) );
1864
1865	/* fill in the rest of the aio_workq_entry */
1866	entryp->procp = procp;
1867	entryp->uaiocbp = aiocbp;
1868	entryp->flags |= kindOfIO;
1869	entryp->group_tag = group_tag;
1870	entryp->aio_map = VM_MAP_NULL;
1871	entryp->aio_refcount = 0;
1872
1873	if ( proc_is64bit(procp) ) {
1874		struct user64_aiocb aiocb64;
1875
1876		result = copyin( aiocbp, &aiocb64, sizeof(aiocb64) );
1877		if (result == 0 )
1878			do_munge_aiocb_user64_to_user(&aiocb64, &entryp->aiocb);
1879
1880	} else {
1881		struct user32_aiocb aiocb32;
1882
1883		result = copyin( aiocbp, &aiocb32, sizeof(aiocb32) );
1884		if ( result == 0 )
1885			do_munge_aiocb_user32_to_user( &aiocb32, &entryp->aiocb );
1886	}
1887
1888	if ( result != 0 ) {
1889		result = EAGAIN;
1890		goto error_exit;
1891	}
1892
1893	/* get a reference to the user land map in order to keep it around */
1894	entryp->aio_map = get_task_map( procp->task );
1895	vm_map_reference( entryp->aio_map );
1896
1897	/* do some more validation on the aiocb and embedded file descriptor */
1898	result = aio_validate( entryp );
1899
1900error_exit:
1901	if ( result && entryp != NULL ) {
1902		zfree( aio_workq_zonep, entryp );
1903		entryp = NULL;
1904	}
1905
1906	return ( entryp );
1907}
1908
1909
1910/*
1911 * aio_queue_async_request - queue up an async IO request on our work queue then
1912 * wake up one of our worker threads to do the actual work.  We get a reference
1913 * to our caller's user land map in order to keep it around while we are
1914 * processing the request.
1915 */
1916static int
1917aio_queue_async_request(proc_t procp, user_addr_t aiocbp, int kindOfIO )
1918{
1919	aio_workq_entry	*entryp;
1920	int		result;
1921	int		old_count;
1922
1923	old_count = aio_increment_total_count();
1924	if (old_count >= aio_max_requests) {
1925		result = EAGAIN;
1926		goto error_noalloc;
1927	}
1928
1929	entryp = aio_create_queue_entry( procp, aiocbp, 0, kindOfIO);
1930	if ( entryp == NULL ) {
1931		result = EAGAIN;
1932		goto error_noalloc;
1933	}
1934
1935
1936	aio_proc_lock_spin(procp);
1937
1938	if ( is_already_queued( entryp->procp, entryp->uaiocbp ) == TRUE ) {
1939		result = EAGAIN;
1940		goto error_exit;
1941	}
1942
1943	/* check our aio limits to throttle bad or rude user land behavior */
1944	if (aio_get_process_count( procp ) >= aio_max_requests_per_process) {
1945		printf("aio_queue_async_request(): too many in flight for proc: %d.\n", procp->p_aio_total_count);
1946		result = EAGAIN;
1947		goto error_exit;
1948	}
1949
1950	/* Add the IO to proc and work queues, wake up threads as appropriate */
1951	lck_mtx_convert_spin(aio_proc_mutex(procp));
1952	aio_enqueue_work(procp, entryp, 1);
1953
1954	aio_proc_unlock(procp);
1955
1956	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_work_queued)) | DBG_FUNC_NONE,
1957		     	  (int)procp, (int)aiocbp, 0, 0, 0 );
1958
1959	return( 0 );
1960
1961error_exit:
1962	/*
1963	 * This entry has not been queued up so no worries about
1964	 * unlocked state and aio_map
1965	 */
1966	aio_proc_unlock(procp);
1967	aio_free_request(entryp);
1968
1969error_noalloc:
1970	aio_decrement_total_count();
1971
1972	return( result );
1973
1974} /* aio_queue_async_request */
1975
1976
1977/*
1978 * lio_create_entry
1979 *
1980 * Allocate an aio_workq_entry and fill it in.  If all goes well return 0
1981 * and pass the aio_workq_entry pointer back to our caller.
1982 *
1983 * Parameters:	procp			The process makign the request
1984 *		aiocbp			The aio context buffer pointer
1985 *		group_tag		The group tag used to indicate a
1986 *					group of operations has completed
1987 *		entrypp			Pointer to the pointer to receive the
1988 *					address of the created aio_workq_entry
1989 *
1990 * Returns:	0			Successfully created
1991 *		EAGAIN			Try again (usually resource shortage)
1992 *
1993 *
1994 * Notes:	We get a reference to our caller's user land map in order
1995 *		to keep it around while we are processing the request.
1996 *
1997 *		lio_listio calls behave differently at completion they do
1998 *		completion notification when all async IO requests have
1999 *		completed.  We use group_tag to tag IO requests that behave
2000 *		in the delay notification manner.
2001 *
2002 *		All synchronous operations are considered to not have a
2003 *		signal routine associated with them (sigp == USER_ADDR_NULL).
2004 */
2005static int
2006lio_create_entry(proc_t procp, user_addr_t aiocbp, void *group_tag,
2007		aio_workq_entry **entrypp )
2008{
2009	aio_workq_entry	*entryp;
2010	int		result;
2011
2012	entryp = aio_create_queue_entry( procp, aiocbp, group_tag, AIO_LIO);
2013	if ( entryp == NULL ) {
2014		result = EAGAIN;
2015		goto error_exit;
2016	}
2017
2018	/*
2019	 * Look for lio_listio LIO_NOP requests and ignore them; this is
2020	 * not really an error, but we need to free our aio_workq_entry.
2021	 */
2022	if ( entryp->aiocb.aio_lio_opcode == LIO_NOP ) {
2023		result = 0;
2024		goto error_exit;
2025	}
2026
2027	*entrypp = entryp;
2028	return( 0 );
2029
2030error_exit:
2031
2032	if ( entryp != NULL ) {
2033		/*
2034		 * This entry has not been queued up so no worries about
2035		 * unlocked state and aio_map
2036		 */
2037		aio_free_request(entryp);
2038	}
2039
2040	return( result );
2041
2042} /* lio_create_entry */
2043
2044
2045/*
2046 * aio_free_request - remove our reference on the user land map and
2047 * free the work queue entry resources.  The entry is off all lists
2048 * and has zero refcount, so no one can have a pointer to it.
2049 */
2050
2051static int
2052aio_free_request(aio_workq_entry *entryp)
2053{
2054	/* remove our reference to the user land map. */
2055	if ( VM_MAP_NULL != entryp->aio_map) {
2056		vm_map_deallocate(entryp->aio_map);
2057	}
2058
2059	entryp->aio_refcount = -1; /* A bit of poisoning in case of bad refcounting. */
2060
2061	zfree( aio_workq_zonep, entryp );
2062
2063	return( 0 );
2064
2065} /* aio_free_request */
2066
2067
2068/*
2069 * aio_validate
2070 *
2071 * validate the aiocb passed in by one of the aio syscalls.
2072 */
2073static int
2074aio_validate( aio_workq_entry *entryp )
2075{
2076	struct fileproc 				*fp;
2077	int							flag;
2078	int							result;
2079
2080	result = 0;
2081
2082	if ( (entryp->flags & AIO_LIO) != 0 ) {
2083		if ( entryp->aiocb.aio_lio_opcode == LIO_READ )
2084			entryp->flags |= AIO_READ;
2085		else if ( entryp->aiocb.aio_lio_opcode == LIO_WRITE )
2086			entryp->flags |= AIO_WRITE;
2087		else if ( entryp->aiocb.aio_lio_opcode == LIO_NOP )
2088			return( 0 );
2089		else
2090			return( EINVAL );
2091	}
2092
2093	flag = FREAD;
2094	if ( (entryp->flags & (AIO_WRITE | AIO_FSYNC | AIO_DSYNC)) != 0 ) {
2095		flag = FWRITE;
2096	}
2097
2098	if ( (entryp->flags & (AIO_READ | AIO_WRITE)) != 0 ) {
2099		if ( entryp->aiocb.aio_nbytes > INT_MAX		||
2100			 entryp->aiocb.aio_buf == USER_ADDR_NULL ||
2101			 entryp->aiocb.aio_offset < 0 )
2102			return( EINVAL );
2103	}
2104
2105	/*
2106	 * validate aiocb.aio_sigevent.  at this point we only support
2107	 * sigev_notify equal to SIGEV_SIGNAL or SIGEV_NONE.  this means
2108	 * sigev_value, sigev_notify_function, and sigev_notify_attributes
2109	 * are ignored, since SIGEV_THREAD is unsupported.  This is consistent
2110	 * with no [RTS] (RalTime Signal) option group support.
2111	 */
2112	switch ( entryp->aiocb.aio_sigevent.sigev_notify ) {
2113	case SIGEV_SIGNAL:
2114	    {
2115		int		signum;
2116
2117		/* make sure we have a valid signal number */
2118		signum = entryp->aiocb.aio_sigevent.sigev_signo;
2119		if ( signum <= 0 || signum >= NSIG ||
2120			 signum == SIGKILL || signum == SIGSTOP )
2121			return (EINVAL);
2122	    }
2123	    break;
2124
2125	case SIGEV_NONE:
2126		break;
2127
2128	case SIGEV_THREAD:
2129		/* Unsupported [RTS] */
2130
2131	default:
2132		return (EINVAL);
2133	}
2134
2135	/* validate the file descriptor and that the file was opened
2136	 * for the appropriate read / write access.
2137	 */
2138	proc_fdlock(entryp->procp);
2139
2140	result = fp_lookup( entryp->procp, entryp->aiocb.aio_fildes, &fp , 1);
2141	if ( result == 0 ) {
2142		if ( (fp->f_fglob->fg_flag & flag) == 0 ) {
2143			/* we don't have read or write access */
2144			result = EBADF;
2145		}
2146		else if ( fp->f_fglob->fg_type != DTYPE_VNODE ) {
2147			/* this is not a file */
2148			result = ESPIPE;
2149		} else
2150		        fp->f_flags |= FP_AIOISSUED;
2151
2152		fp_drop(entryp->procp, entryp->aiocb.aio_fildes, fp , 1);
2153	}
2154	else {
2155		result = EBADF;
2156	}
2157
2158	proc_fdunlock(entryp->procp);
2159
2160	return( result );
2161
2162} /* aio_validate */
2163
2164static int
2165aio_increment_total_count()
2166{
2167	return OSIncrementAtomic(&aio_anchor.aio_total_count);
2168}
2169
2170static int
2171aio_decrement_total_count()
2172{
2173	int old = OSDecrementAtomic(&aio_anchor.aio_total_count);
2174	if (old <= 0) {
2175		panic("Negative total AIO count!\n");
2176	}
2177
2178	return old;
2179}
2180
2181static int
2182aio_get_process_count(proc_t procp )
2183{
2184	return procp->p_aio_total_count;
2185
2186} /* aio_get_process_count */
2187
2188static int
2189aio_get_all_queues_count( void )
2190{
2191	return aio_anchor.aio_total_count;
2192
2193} /* aio_get_all_queues_count */
2194
2195
2196/*
2197 * do_aio_completion.  Handle async IO completion.
2198 */
2199static void
2200do_aio_completion( aio_workq_entry *entryp )
2201{
2202
2203	boolean_t		lastLioCompleted = FALSE;
2204	aio_lio_context	*lio_context = NULL;
2205	int waiter = 0;
2206
2207	lio_context = (aio_lio_context *)entryp->group_tag;
2208
2209	if (lio_context != NULL) {
2210
2211		aio_proc_lock_spin(entryp->procp);
2212
2213		/* Account for this I/O completing. */
2214	 	lio_context->io_completed++;
2215
2216		/* Are we done with this lio context? */
2217	 	if (lio_context->io_issued == lio_context->io_completed) {
2218	 		lastLioCompleted = TRUE;
2219	 	}
2220
2221		waiter = lio_context->io_waiter;
2222
2223		/* explicit wakeup of lio_listio() waiting in LIO_WAIT */
2224		if ((entryp->flags & AIO_LIO_NOTIFY) && (lastLioCompleted) && (waiter != 0)) {
2225			/* wake up the waiter */
2226			wakeup(lio_context);
2227		}
2228
2229		aio_proc_unlock(entryp->procp);
2230	}
2231
2232	if ( entryp->aiocb.aio_sigevent.sigev_notify == SIGEV_SIGNAL &&
2233		 (entryp->flags & AIO_DISABLE) == 0 ) {
2234
2235		boolean_t	performSignal = FALSE;
2236		 if (lio_context == NULL) {
2237		 	performSignal = TRUE;
2238		 }
2239		 else {
2240			/*
2241			 * If this was the last request in the group and a signal
2242			 * is desired, send one.
2243			 */
2244			performSignal = lastLioCompleted;
2245		 }
2246
2247		 if (performSignal) {
2248
2249			KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_completion_sig)) | DBG_FUNC_NONE,
2250				 (int)entryp->procp, (int)entryp->uaiocbp,
2251				 entryp->aiocb.aio_sigevent.sigev_signo, 0, 0 );
2252
2253			psignal( entryp->procp, entryp->aiocb.aio_sigevent.sigev_signo );
2254		}
2255	}
2256
2257	if ((entryp->flags & AIO_EXIT_WAIT) && (entryp->flags & AIO_CLOSE_WAIT)) {
2258		panic("Close and exit flags set at the same time\n");
2259	}
2260
2261	/*
2262	 * need to handle case where a process is trying to exit, exec, or
2263	 * close and is currently waiting for active aio requests to complete.
2264	 * If AIO_CLEANUP_WAIT is set then we need to look to see if there are any
2265	 * other requests in the active queue for this process.  If there are
2266	 * none then wakeup using the AIO_CLEANUP_SLEEP_CHAN tsleep channel.
2267	 * If there are some still active then do nothing - we only want to
2268	 * wakeup when all active aio requests for the process are complete.
2269	 *
2270	 * Don't need to lock the entry or proc to check the cleanup flag.  It can only be
2271	 * set for cancellation, while the entryp is still on a proc list; now it's
2272	 * off, so that flag is already set if it's going to be.
2273	 */
2274	if ( (entryp->flags & AIO_EXIT_WAIT) != 0 ) {
2275		int		active_requests;
2276
2277		KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_completion_cleanup_wait)) | DBG_FUNC_NONE,
2278					  (int)entryp->procp, (int)entryp->uaiocbp, 0, 0, 0 );
2279
2280		aio_proc_lock_spin(entryp->procp);
2281		active_requests = aio_active_requests_for_process( entryp->procp );
2282		if ( active_requests < 1 ) {
2283			/*
2284			 * no active aio requests for this process, continue exiting.  In this
2285			 * case, there should be no one else waiting ont he proc in AIO...
2286			 */
2287			wakeup_one((caddr_t)&entryp->procp->AIO_CLEANUP_SLEEP_CHAN);
2288			aio_proc_unlock(entryp->procp);
2289
2290			KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_completion_cleanup_wake)) | DBG_FUNC_NONE,
2291					  	  (int)entryp->procp, (int)entryp->uaiocbp, 0, 0, 0 );
2292		} else {
2293			aio_proc_unlock(entryp->procp);
2294		}
2295	}
2296
2297	if ( (entryp->flags & AIO_CLOSE_WAIT) != 0 ) {
2298		int		active_requests;
2299
2300		KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_completion_cleanup_wait)) | DBG_FUNC_NONE,
2301					  (int)entryp->procp, (int)entryp->uaiocbp, 0, 0, 0 );
2302
2303		aio_proc_lock_spin(entryp->procp);
2304		active_requests = aio_proc_active_requests_for_file( entryp->procp, entryp->aiocb.aio_fildes);
2305		if ( active_requests < 1 ) {
2306			/* Can't wakeup_one(); multiple closes might be in progress. */
2307			wakeup(&entryp->procp->AIO_CLEANUP_SLEEP_CHAN);
2308			aio_proc_unlock(entryp->procp);
2309
2310			KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_completion_cleanup_wake)) | DBG_FUNC_NONE,
2311					  	  (int)entryp->procp, (int)entryp->uaiocbp, 0, 0, 0 );
2312		} else {
2313			aio_proc_unlock(entryp->procp);
2314		}
2315	}
2316	/*
2317	 * A thread in aio_suspend() wants to known about completed IOs.  If it checked
2318	 * the done list before we moved our AIO there, then it already asserted its wait,
2319	 * and we can wake it up without holding the lock.  If it checked the list after
2320	 * we did our move, then it already has seen the AIO that we moved.  Herego, we
2321	 * can do our wakeup without holding the lock.
2322	 */
2323	wakeup( (caddr_t) &entryp->procp->AIO_SUSPEND_SLEEP_CHAN );
2324	KERNEL_DEBUG( (BSDDBG_CODE(DBG_BSD_AIO, AIO_completion_suspend_wake)) | DBG_FUNC_NONE,
2325				  (int)entryp->procp, (int)entryp->uaiocbp, 0, 0, 0 );
2326
2327	/*
2328	 * free the LIO context if the last lio completed and no thread is
2329	 * waiting
2330	 */
2331	if (lastLioCompleted && (waiter == 0))
2332		free_lio_context (lio_context);
2333
2334
2335} /* do_aio_completion */
2336
2337
2338/*
2339 * do_aio_read
2340 */
2341static int
2342do_aio_read( aio_workq_entry *entryp )
2343{
2344	struct fileproc		*fp;
2345	int					error;
2346	struct vfs_context	context;
2347
2348	if ( (error = fp_lookup(entryp->procp, entryp->aiocb.aio_fildes, &fp , 0)) )
2349		return(error);
2350	if ( (fp->f_fglob->fg_flag & FREAD) == 0 ) {
2351		fp_drop(entryp->procp, entryp->aiocb.aio_fildes, fp, 0);
2352		return(EBADF);
2353	}
2354
2355	/*
2356	 * <rdar://4714366>
2357	 * Needs vfs_context_t from vfs_context_create() in entryp!
2358	 */
2359	context.vc_thread = proc_thread(entryp->procp);	/* XXX */
2360	context.vc_ucred = fp->f_fglob->fg_cred;
2361
2362	error = dofileread(&context, fp,
2363				entryp->aiocb.aio_buf,
2364				entryp->aiocb.aio_nbytes,
2365				entryp->aiocb.aio_offset, FOF_OFFSET,
2366				&entryp->returnval);
2367	fp_drop(entryp->procp, entryp->aiocb.aio_fildes, fp, 0);
2368
2369	return( error );
2370
2371} /* do_aio_read */
2372
2373
2374/*
2375 * do_aio_write
2376 */
2377static int
2378do_aio_write( aio_workq_entry *entryp )
2379{
2380	struct fileproc 		*fp;
2381	int				error, flags;
2382	struct vfs_context		context;
2383
2384	if ( (error = fp_lookup(entryp->procp, entryp->aiocb.aio_fildes, &fp , 0)) )
2385		return(error);
2386	if ( (fp->f_fglob->fg_flag & FWRITE) == 0 ) {
2387		fp_drop(entryp->procp, entryp->aiocb.aio_fildes, fp, 0);
2388		return(EBADF);
2389	}
2390
2391	flags = FOF_PCRED;
2392	if ( (fp->f_fglob->fg_flag & O_APPEND) == 0 ) {
2393		flags |= FOF_OFFSET;
2394	}
2395
2396	/*
2397	 * <rdar://4714366>
2398	 * Needs vfs_context_t from vfs_context_create() in entryp!
2399	 */
2400	context.vc_thread = proc_thread(entryp->procp);	/* XXX */
2401	context.vc_ucred = fp->f_fglob->fg_cred;
2402
2403	/* NB: tell dofilewrite the offset, and to use the proc cred */
2404	error = dofilewrite(&context,
2405				fp,
2406				entryp->aiocb.aio_buf,
2407				entryp->aiocb.aio_nbytes,
2408				entryp->aiocb.aio_offset,
2409				flags,
2410				&entryp->returnval);
2411
2412	fp_drop(entryp->procp, entryp->aiocb.aio_fildes, fp, 0);
2413
2414	return( error );
2415
2416} /* do_aio_write */
2417
2418
2419/*
2420 * aio_active_requests_for_process - return number of active async IO
2421 * requests for the given process.
2422 */
2423static int
2424aio_active_requests_for_process(proc_t procp )
2425{
2426	return( procp->p_aio_active_count );
2427
2428} /* aio_active_requests_for_process */
2429
2430/*
2431 * Called with the proc locked.
2432 */
2433static int
2434aio_proc_active_requests_for_file(proc_t procp, int fd)
2435{
2436	int count = 0;
2437	aio_workq_entry *entryp;
2438	TAILQ_FOREACH(entryp, &procp->p_aio_activeq, aio_proc_link) {
2439		if (entryp->aiocb.aio_fildes == fd) {
2440			count++;
2441		}
2442	}
2443
2444	return count;
2445} /* aio_active_requests_for_process */
2446
2447
2448
2449/*
2450 * do_aio_fsync
2451 */
2452static int
2453do_aio_fsync( aio_workq_entry *entryp )
2454{
2455	struct vfs_context 	context;
2456	struct vnode 		*vp;
2457	struct fileproc		*fp;
2458	int			sync_flag;
2459	int			error;
2460
2461	/*
2462	 * We are never called unless either AIO_FSYNC or AIO_DSYNC are set.
2463	 *
2464	 * If AIO_DSYNC is set, we can tell the lower layers that it is OK
2465	 * to mark for update the metadata not strictly necessary for data
2466	 * retrieval, rather than forcing it to disk.
2467	 *
2468	 * If AIO_FSYNC is set, we have to also wait for metadata not really
2469	 * necessary to data retrival are committed to stable storage (e.g.
2470	 * atime, mtime, ctime, etc.).
2471	 *
2472	 * Metadata necessary for data retrieval ust be committed to stable
2473	 * storage in either case (file length, etc.).
2474	 */
2475	if (entryp->flags & AIO_FSYNC)
2476		sync_flag = MNT_WAIT;
2477	else
2478		sync_flag = MNT_DWAIT;
2479
2480	error = fp_getfvp( entryp->procp, entryp->aiocb.aio_fildes, &fp, &vp);
2481	if ( error == 0 ) {
2482		if ( (error = vnode_getwithref(vp)) ) {
2483		        fp_drop(entryp->procp, entryp->aiocb.aio_fildes, fp, 0);
2484			entryp->returnval = -1;
2485			return(error);
2486		}
2487		context.vc_thread = current_thread();
2488		context.vc_ucred = fp->f_fglob->fg_cred;
2489
2490		error = VNOP_FSYNC( vp, sync_flag, &context);
2491
2492		(void)vnode_put(vp);
2493
2494		fp_drop(entryp->procp, entryp->aiocb.aio_fildes, fp, 0);
2495	}
2496	if ( error != 0 )
2497		entryp->returnval = -1;
2498
2499	return( error );
2500
2501} /* do_aio_fsync */
2502
2503
2504/*
2505 * is_already_queued - runs through our queues to see if the given
2506 * aiocbp / process is there.  Returns TRUE if there is a match
2507 * on any of our aio queues.
2508 *
2509 * Called with proc aio lock held (can be held spin)
2510 */
2511static boolean_t
2512is_already_queued(proc_t procp,
2513					user_addr_t aiocbp )
2514{
2515	aio_workq_entry		 	*entryp;
2516	boolean_t				result;
2517
2518	result = FALSE;
2519
2520	/* look for matches on our queue of async IO requests that have completed */
2521	TAILQ_FOREACH( entryp, &procp->p_aio_doneq, aio_proc_link ) {
2522		if ( aiocbp == entryp->uaiocbp ) {
2523			result = TRUE;
2524			goto ExitThisRoutine;
2525		}
2526	}
2527
2528	/* look for matches on our queue of active async IO requests */
2529	TAILQ_FOREACH( entryp, &procp->p_aio_activeq, aio_proc_link ) {
2530		if ( aiocbp == entryp->uaiocbp ) {
2531			result = TRUE;
2532			goto ExitThisRoutine;
2533		}
2534	}
2535
2536ExitThisRoutine:
2537	return( result );
2538
2539} /* is_already_queued */
2540
2541
2542static void
2543free_lio_context(aio_lio_context* context)
2544{
2545
2546#if DEBUG
2547	OSDecrementAtomic(&lio_contexts_alloced);
2548#endif /* DEBUG */
2549
2550	FREE( context, M_TEMP );
2551
2552} /* free_lio_context */
2553
2554
2555/*
2556 * aio initialization
2557 */
2558__private_extern__ void
2559aio_init( void )
2560{
2561	int			i;
2562
2563	aio_lock_grp_attr = lck_grp_attr_alloc_init();
2564	aio_proc_lock_grp = lck_grp_alloc_init("aio_proc", aio_lock_grp_attr);;
2565	aio_entry_lock_grp = lck_grp_alloc_init("aio_entry", aio_lock_grp_attr);;
2566	aio_queue_lock_grp = lck_grp_alloc_init("aio_queue", aio_lock_grp_attr);;
2567	aio_lock_attr = lck_attr_alloc_init();
2568
2569	lck_mtx_init(&aio_entry_mtx, aio_entry_lock_grp, aio_lock_attr);
2570	lck_mtx_init(&aio_proc_mtx, aio_proc_lock_grp, aio_lock_attr);
2571
2572	aio_anchor.aio_inflight_count = 0;
2573	aio_anchor.aio_done_count = 0;
2574	aio_anchor.aio_total_count = 0;
2575	aio_anchor.aio_num_workqs = AIO_NUM_WORK_QUEUES;
2576
2577	for (i = 0; i < AIO_NUM_WORK_QUEUES; i++) {
2578		aio_workq_init(&aio_anchor.aio_async_workqs[i]);
2579	}
2580
2581
2582	i = sizeof( aio_workq_entry );
2583	aio_workq_zonep = zinit( i, i * aio_max_requests, i * aio_max_requests, "aiowq" );
2584
2585	_aio_create_worker_threads( aio_worker_threads );
2586
2587} /* aio_init */
2588
2589
2590/*
2591 * aio worker threads created here.
2592 */
2593__private_extern__ void
2594_aio_create_worker_threads( int num )
2595{
2596	int			i;
2597
2598	/* create some worker threads to handle the async IO requests */
2599	for ( i = 0; i < num; i++ ) {
2600		thread_t		myThread;
2601
2602		if ( KERN_SUCCESS != kernel_thread_start((thread_continue_t)aio_work_thread, NULL, &myThread) ) {
2603			printf( "%s - failed to create a work thread \n", __FUNCTION__ );
2604		}
2605		else
2606			thread_deallocate(myThread);
2607	}
2608
2609	return;
2610
2611} /* _aio_create_worker_threads */
2612
2613/*
2614 * Return the current activation utask
2615 */
2616task_t
2617get_aiotask(void)
2618{
2619	return  ((struct uthread *)get_bsdthread_info(current_thread()))->uu_aio_task;
2620}
2621
2622
2623/*
2624 * In the case of an aiocb from a
2625 * 32-bit process we need to expand some longs and pointers to the correct
2626 * sizes in order to let downstream code always work on the same type of
2627 * aiocb (in our case that is a user_aiocb)
2628 */
2629static void
2630do_munge_aiocb_user32_to_user( struct user32_aiocb *my_aiocbp, struct user_aiocb *the_user_aiocbp )
2631{
2632	the_user_aiocbp->aio_fildes = my_aiocbp->aio_fildes;
2633	the_user_aiocbp->aio_offset = my_aiocbp->aio_offset;
2634	the_user_aiocbp->aio_buf = CAST_USER_ADDR_T(my_aiocbp->aio_buf);
2635	the_user_aiocbp->aio_nbytes = my_aiocbp->aio_nbytes;
2636	the_user_aiocbp->aio_reqprio = my_aiocbp->aio_reqprio;
2637	the_user_aiocbp->aio_lio_opcode = my_aiocbp->aio_lio_opcode;
2638
2639	/* special case here.  since we do not know if sigev_value is an */
2640	/* int or a ptr we do NOT cast the ptr to a user_addr_t.   This  */
2641	/* means if we send this info back to user space we need to remember */
2642	/* sigev_value was not expanded for the 32-bit case.  */
2643	/* NOTE - this does NOT affect us since we don't support sigev_value */
2644	/* yet in the aio context.  */
2645	//LP64
2646	the_user_aiocbp->aio_sigevent.sigev_notify = my_aiocbp->aio_sigevent.sigev_notify;
2647	the_user_aiocbp->aio_sigevent.sigev_signo = my_aiocbp->aio_sigevent.sigev_signo;
2648	the_user_aiocbp->aio_sigevent.sigev_value.size_equivalent.sival_int =
2649		my_aiocbp->aio_sigevent.sigev_value.size_equivalent.sival_int;
2650	the_user_aiocbp->aio_sigevent.sigev_notify_function =
2651		CAST_USER_ADDR_T(my_aiocbp->aio_sigevent.sigev_notify_function);
2652	the_user_aiocbp->aio_sigevent.sigev_notify_attributes =
2653		CAST_USER_ADDR_T(my_aiocbp->aio_sigevent.sigev_notify_attributes);
2654}
2655
2656/* Similar for 64-bit user process, so that we don't need to satisfy
2657 * the alignment constraints of the original user64_aiocb
2658 */
2659static void
2660do_munge_aiocb_user64_to_user( struct user64_aiocb *my_aiocbp, struct user_aiocb *the_user_aiocbp )
2661{
2662	the_user_aiocbp->aio_fildes = my_aiocbp->aio_fildes;
2663	the_user_aiocbp->aio_offset = my_aiocbp->aio_offset;
2664	the_user_aiocbp->aio_buf = my_aiocbp->aio_buf;
2665	the_user_aiocbp->aio_nbytes = my_aiocbp->aio_nbytes;
2666	the_user_aiocbp->aio_reqprio = my_aiocbp->aio_reqprio;
2667	the_user_aiocbp->aio_lio_opcode = my_aiocbp->aio_lio_opcode;
2668
2669	the_user_aiocbp->aio_sigevent.sigev_notify = my_aiocbp->aio_sigevent.sigev_notify;
2670	the_user_aiocbp->aio_sigevent.sigev_signo = my_aiocbp->aio_sigevent.sigev_signo;
2671	the_user_aiocbp->aio_sigevent.sigev_value.size_equivalent.sival_int =
2672		my_aiocbp->aio_sigevent.sigev_value.size_equivalent.sival_int;
2673	the_user_aiocbp->aio_sigevent.sigev_notify_function =
2674		my_aiocbp->aio_sigevent.sigev_notify_function;
2675	the_user_aiocbp->aio_sigevent.sigev_notify_attributes =
2676		my_aiocbp->aio_sigevent.sigev_notify_attributes;
2677}
2678