xref: /freebsd/sys/kern/vfs_aio.c (revision a79b71281cd63ad7a6cc43a6d5673a2510b51630)
1 /*
2  * Copyright (c) 1997 John S. Dyson.  All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. John S. Dyson's name may not be used to endorse or promote products
10  *    derived from this software without specific prior written permission.
11  *
12  * DISCLAIMER:  This code isn't warranted to do anything useful.  Anything
13  * bad that happens because of using this software isn't the responsibility
14  * of the author.  This software is distributed AS-IS.
15  *
16  * $FreeBSD$
17  */
18 
19 /*
20  * This file contains support for the POSIX 1003.1B AIO/LIO facility.
21  */
22 
23 #include <sys/param.h>
24 #include <sys/systm.h>
25 #include <sys/bio.h>
26 #include <sys/buf.h>
27 #include <sys/sysproto.h>
28 #include <sys/filedesc.h>
29 #include <sys/kernel.h>
30 #include <sys/fcntl.h>
31 #include <sys/file.h>
32 #include <sys/lock.h>
33 #include <sys/unistd.h>
34 #include <sys/proc.h>
35 #include <sys/resourcevar.h>
36 #include <sys/signalvar.h>
37 #include <sys/protosw.h>
38 #include <sys/socketvar.h>
39 #include <sys/sysctl.h>
40 #include <sys/vnode.h>
41 #include <sys/conf.h>
42 #include <sys/event.h>
43 
44 #include <vm/vm.h>
45 #include <vm/vm_extern.h>
46 #include <vm/pmap.h>
47 #include <vm/vm_map.h>
48 #include <vm/vm_zone.h>
49 #include <sys/aio.h>
50 
51 #include <machine/limits.h>
52 #include "opt_vfs_aio.h"
53 
54 static	long jobrefid;
55 
56 #define JOBST_NULL		0x0
57 #define	JOBST_JOBQPROC		0x1
58 #define JOBST_JOBQGLOBAL	0x2
59 #define JOBST_JOBRUNNING	0x3
60 #define JOBST_JOBFINISHED	0x4
61 #define	JOBST_JOBQBUF		0x5
62 #define	JOBST_JOBBFINISHED	0x6
63 
64 #ifndef MAX_AIO_PER_PROC
65 #define MAX_AIO_PER_PROC	32
66 #endif
67 
68 #ifndef MAX_AIO_QUEUE_PER_PROC
69 #define MAX_AIO_QUEUE_PER_PROC	256 /* Bigger than AIO_LISTIO_MAX */
70 #endif
71 
72 #ifndef MAX_AIO_PROCS
73 #define MAX_AIO_PROCS		32
74 #endif
75 
76 #ifndef MAX_AIO_QUEUE
77 #define	MAX_AIO_QUEUE		1024 /* Bigger than AIO_LISTIO_MAX */
78 #endif
79 
80 #ifndef TARGET_AIO_PROCS
81 #define TARGET_AIO_PROCS	4
82 #endif
83 
84 #ifndef MAX_BUF_AIO
85 #define MAX_BUF_AIO		16
86 #endif
87 
88 #ifndef AIOD_TIMEOUT_DEFAULT
89 #define	AIOD_TIMEOUT_DEFAULT	(10 * hz)
90 #endif
91 
92 #ifndef AIOD_LIFETIME_DEFAULT
93 #define AIOD_LIFETIME_DEFAULT	(30 * hz)
94 #endif
95 
96 static int max_aio_procs = MAX_AIO_PROCS;
97 static int num_aio_procs = 0;
98 static int target_aio_procs = TARGET_AIO_PROCS;
99 static int max_queue_count = MAX_AIO_QUEUE;
100 static int num_queue_count = 0;
101 static int num_buf_aio = 0;
102 static int num_aio_resv_start = 0;
103 static int aiod_timeout;
104 static int aiod_lifetime;
105 
106 static int max_aio_per_proc = MAX_AIO_PER_PROC;
107 static int max_aio_queue_per_proc = MAX_AIO_QUEUE_PER_PROC;
108 static int max_buf_aio = MAX_BUF_AIO;
109 
110 SYSCTL_NODE(_vfs, OID_AUTO, aio, CTLFLAG_RW, 0, "AIO mgmt");
111 
112 SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_per_proc,
113 	CTLFLAG_RW, &max_aio_per_proc, 0, "");
114 
115 SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_queue_per_proc,
116 	CTLFLAG_RW, &max_aio_queue_per_proc, 0, "");
117 
118 SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_procs,
119 	CTLFLAG_RW, &max_aio_procs, 0, "");
120 
121 SYSCTL_INT(_vfs_aio, OID_AUTO, num_aio_procs,
122 	CTLFLAG_RD, &num_aio_procs, 0, "");
123 
124 SYSCTL_INT(_vfs_aio, OID_AUTO, num_queue_count,
125 	CTLFLAG_RD, &num_queue_count, 0, "");
126 
127 SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_queue,
128 	CTLFLAG_RW, &max_queue_count, 0, "");
129 
130 SYSCTL_INT(_vfs_aio, OID_AUTO, target_aio_procs,
131 	CTLFLAG_RW, &target_aio_procs, 0, "");
132 
133 SYSCTL_INT(_vfs_aio, OID_AUTO, max_buf_aio,
134 	CTLFLAG_RW, &max_buf_aio, 0, "");
135 
136 SYSCTL_INT(_vfs_aio, OID_AUTO, num_buf_aio,
137 	CTLFLAG_RD, &num_buf_aio, 0, "");
138 
139 SYSCTL_INT(_vfs_aio, OID_AUTO, aiod_lifetime,
140 	CTLFLAG_RW, &aiod_lifetime, 0, "");
141 
142 SYSCTL_INT(_vfs_aio, OID_AUTO, aiod_timeout,
143 	CTLFLAG_RW, &aiod_timeout, 0, "");
144 
145 /*
146  * AIO process info
147  */
148 #define AIOP_FREE	0x1			/* proc on free queue */
149 #define AIOP_SCHED	0x2			/* proc explicitly scheduled */
150 
151 struct aioproclist {
152 	int aioprocflags;			/* AIO proc flags */
153 	TAILQ_ENTRY(aioproclist) list;		/* List of processes */
154 	struct proc *aioproc;			/* The AIO thread */
155 	TAILQ_HEAD (,aiocblist) jobtorun;	/* suggested job to run */
156 };
157 
158 /*
159  * data-structure for lio signal management
160  */
161 struct aio_liojob {
162 	int	lioj_flags;
163 	int	lioj_buffer_count;
164 	int	lioj_buffer_finished_count;
165 	int	lioj_queue_count;
166 	int	lioj_queue_finished_count;
167 	struct	sigevent lioj_signal;	/* signal on all I/O done */
168 	TAILQ_ENTRY	(aio_liojob) lioj_list;
169 	struct	kaioinfo *lioj_ki;
170 };
171 #define	LIOJ_SIGNAL		0x1	/* signal on all done (lio) */
172 #define	LIOJ_SIGNAL_POSTED	0x2	/* signal has been posted */
173 
174 /*
175  * per process aio data structure
176  */
177 struct kaioinfo {
178 	int	kaio_flags;		/* per process kaio flags */
179 	int	kaio_maxactive_count;	/* maximum number of AIOs */
180 	int	kaio_active_count;	/* number of currently used AIOs */
181 	int	kaio_qallowed_count;	/* maxiumu size of AIO queue */
182 	int	kaio_queue_count;	/* size of AIO queue */
183 	int	kaio_ballowed_count;	/* maximum number of buffers */
184 	int	kaio_queue_finished_count; /* number of daemon jobs finished */
185 	int	kaio_buffer_count;	/* number of physio buffers */
186 	int	kaio_buffer_finished_count; /* count of I/O done */
187 	struct 	proc *kaio_p;		/* process that uses this kaio block */
188 	TAILQ_HEAD (,aio_liojob) kaio_liojoblist; /* list of lio jobs */
189 	TAILQ_HEAD (,aiocblist)	kaio_jobqueue;	/* job queue for process */
190 	TAILQ_HEAD (,aiocblist)	kaio_jobdone;	/* done queue for process */
191 	TAILQ_HEAD (,aiocblist)	kaio_bufqueue;	/* buffer job queue for process */
192 	TAILQ_HEAD (,aiocblist)	kaio_bufdone;	/* buffer done queue for process */
193 	TAILQ_HEAD (,aiocblist) kaio_sockqueue; /* queue for aios waiting on sockets */
194 };
195 
196 #define KAIO_RUNDOWN	0x1	/* process is being run down */
197 #define KAIO_WAKEUP	0x2	/* wakeup process when there is a significant event */
198 
199 static TAILQ_HEAD(,aioproclist) aio_freeproc, aio_activeproc;
200 static TAILQ_HEAD(,aiocblist) aio_jobs;			/* Async job list */
201 static TAILQ_HEAD(,aiocblist) aio_bufjobs;		/* Phys I/O job list */
202 static TAILQ_HEAD(,aiocblist) aio_freejobs;		/* Pool of free jobs */
203 
204 static void	aio_init_aioinfo(struct proc *p);
205 static void	aio_onceonly(void *);
206 static int	aio_free_entry(struct aiocblist *aiocbe);
207 static void	aio_process(struct aiocblist *aiocbe);
208 static int	aio_newproc(void);
209 static int	aio_aqueue(struct proc *p, struct aiocb *job, int type);
210 static void	aio_physwakeup(struct buf *bp);
211 static int	aio_fphysio(struct proc *p, struct aiocblist *aiocbe, int type);
212 static int	aio_qphysio(struct proc *p, struct aiocblist *iocb);
213 static void	aio_daemon(void *uproc);
214 
215 static int	filt_aioattach(struct knote *kn);
216 static void	filt_aiodetach(struct knote *kn);
217 static int	filt_aio(struct knote *kn, long hint);
218 
219 struct filterops aio_filtops =
220 	{ 0, filt_aioattach, filt_aiodetach, filt_aio };
221 
222 SYSINIT(aio, SI_SUB_VFS, SI_ORDER_ANY, aio_onceonly, NULL);
223 
224 static vm_zone_t kaio_zone = 0, aiop_zone = 0, aiocb_zone = 0, aiol_zone = 0;
225 static vm_zone_t aiolio_zone = 0;
226 
227 /*
228  * Startup initialization
229  */
230 void
231 aio_onceonly(void *na)
232 {
233 	TAILQ_INIT(&aio_freeproc);
234 	TAILQ_INIT(&aio_activeproc);
235 	TAILQ_INIT(&aio_jobs);
236 	TAILQ_INIT(&aio_bufjobs);
237 	TAILQ_INIT(&aio_freejobs);
238 	kaio_zone = zinit("AIO", sizeof (struct kaioinfo), 0, 0, 1);
239 	aiop_zone = zinit("AIOP", sizeof (struct aioproclist), 0, 0, 1);
240 	aiocb_zone = zinit("AIOCB", sizeof (struct aiocblist), 0, 0, 1);
241 	aiol_zone = zinit("AIOL", AIO_LISTIO_MAX * sizeof (int), 0, 0, 1);
242 	aiolio_zone = zinit("AIOLIO", AIO_LISTIO_MAX * sizeof (struct
243 	    aio_liojob), 0, 0, 1);
244 	aiod_timeout = AIOD_TIMEOUT_DEFAULT;
245 	aiod_lifetime = AIOD_LIFETIME_DEFAULT;
246 	jobrefid = 1;
247 }
248 
249 /*
250  * Init the per-process aioinfo structure.  The aioinfo limits are set
251  * per-process for user limit (resource) management.
252  */
253 void
254 aio_init_aioinfo(struct proc *p)
255 {
256 	struct kaioinfo *ki;
257 	if (p->p_aioinfo == NULL) {
258 		ki = zalloc(kaio_zone);
259 		p->p_aioinfo = ki;
260 		ki->kaio_flags = 0;
261 		ki->kaio_maxactive_count = max_aio_per_proc;
262 		ki->kaio_active_count = 0;
263 		ki->kaio_qallowed_count = max_aio_queue_per_proc;
264 		ki->kaio_queue_count = 0;
265 		ki->kaio_ballowed_count = max_buf_aio;
266 		ki->kaio_buffer_count = 0;
267 		ki->kaio_buffer_finished_count = 0;
268 		ki->kaio_p = p;
269 		TAILQ_INIT(&ki->kaio_jobdone);
270 		TAILQ_INIT(&ki->kaio_jobqueue);
271 		TAILQ_INIT(&ki->kaio_bufdone);
272 		TAILQ_INIT(&ki->kaio_bufqueue);
273 		TAILQ_INIT(&ki->kaio_liojoblist);
274 		TAILQ_INIT(&ki->kaio_sockqueue);
275 	}
276 
277 	while (num_aio_procs < target_aio_procs)
278 		aio_newproc();
279 }
280 
281 /*
282  * Free a job entry.  Wait for completion if it is currently active, but don't
283  * delay forever.  If we delay, we return a flag that says that we have to
284  * restart the queue scan.
285  */
286 int
287 aio_free_entry(struct aiocblist *aiocbe)
288 {
289 	struct kaioinfo *ki;
290 	struct aioproclist *aiop;
291 	struct aio_liojob *lj;
292 	struct proc *p;
293 	int error;
294 	int s;
295 
296 	if (aiocbe->jobstate == JOBST_NULL)
297 		panic("aio_free_entry: freeing already free job");
298 
299 	p = aiocbe->userproc;
300 	ki = p->p_aioinfo;
301 	lj = aiocbe->lio;
302 	if (ki == NULL)
303 		panic("aio_free_entry: missing p->p_aioinfo");
304 
305 	if (aiocbe->jobstate == JOBST_JOBRUNNING) {
306 		if (aiocbe->jobflags & AIOCBLIST_ASYNCFREE)
307 			return 0;
308 		aiocbe->jobflags |= AIOCBLIST_RUNDOWN;
309 		tsleep(aiocbe, PRIBIO|PCATCH, "jobwai", 0);
310 	}
311 	aiocbe->jobflags &= ~AIOCBLIST_ASYNCFREE;
312 
313 	if (aiocbe->bp == NULL) {
314 		if (ki->kaio_queue_count <= 0)
315 			panic("aio_free_entry: process queue size <= 0");
316 		if (num_queue_count <= 0)
317 			panic("aio_free_entry: system wide queue size <= 0");
318 
319 		if (lj) {
320 			lj->lioj_queue_count--;
321 			if (aiocbe->jobflags & AIOCBLIST_DONE)
322 				lj->lioj_queue_finished_count--;
323 		}
324 		ki->kaio_queue_count--;
325 		if (aiocbe->jobflags & AIOCBLIST_DONE)
326 			ki->kaio_queue_finished_count--;
327 		num_queue_count--;
328 	} else {
329 		if (lj) {
330 			lj->lioj_buffer_count--;
331 			if (aiocbe->jobflags & AIOCBLIST_DONE)
332 				lj->lioj_buffer_finished_count--;
333 		}
334 		if (aiocbe->jobflags & AIOCBLIST_DONE)
335 			ki->kaio_buffer_finished_count--;
336 		ki->kaio_buffer_count--;
337 		num_buf_aio--;
338 	}
339 
340 	/* aiocbe is going away, we need to destroy any knotes */
341 	knote_remove(p, &aiocbe->klist);
342 
343 	if ((ki->kaio_flags & KAIO_WAKEUP) || ((ki->kaio_flags & KAIO_RUNDOWN)
344 	    && ((ki->kaio_buffer_count == 0) && (ki->kaio_queue_count == 0)))) {
345 		ki->kaio_flags &= ~KAIO_WAKEUP;
346 		wakeup(p);
347 	}
348 
349 	if (aiocbe->jobstate == JOBST_JOBQBUF) {
350 		if ((error = aio_fphysio(p, aiocbe, 1)) != 0)
351 			return error;
352 		if (aiocbe->jobstate != JOBST_JOBBFINISHED)
353 			panic("aio_free_entry: invalid physio finish-up state");
354 		s = splbio();
355 		TAILQ_REMOVE(&ki->kaio_bufdone, aiocbe, plist);
356 		splx(s);
357 	} else if (aiocbe->jobstate == JOBST_JOBQPROC) {
358 		aiop = aiocbe->jobaioproc;
359 		TAILQ_REMOVE(&aiop->jobtorun, aiocbe, list);
360 	} else if (aiocbe->jobstate == JOBST_JOBQGLOBAL)
361 		TAILQ_REMOVE(&aio_jobs, aiocbe, list);
362 	else if (aiocbe->jobstate == JOBST_JOBFINISHED)
363 		TAILQ_REMOVE(&ki->kaio_jobdone, aiocbe, plist);
364 	else if (aiocbe->jobstate == JOBST_JOBBFINISHED) {
365 		s = splbio();
366 		TAILQ_REMOVE(&ki->kaio_bufdone, aiocbe, plist);
367 		splx(s);
368 		if (aiocbe->bp) {
369 			vunmapbuf(aiocbe->bp);
370 			relpbuf(aiocbe->bp, NULL);
371 			aiocbe->bp = NULL;
372 		}
373 	}
374 	if (lj && (lj->lioj_buffer_count == 0) && (lj->lioj_queue_count == 0)) {
375 		TAILQ_REMOVE(&ki->kaio_liojoblist, lj, lioj_list);
376 		zfree(aiolio_zone, lj);
377 	}
378 	TAILQ_INSERT_HEAD(&aio_freejobs, aiocbe, list);
379 	aiocbe->jobstate = JOBST_NULL;
380 	return 0;
381 }
382 
383 /*
384  * Rundown the jobs for a given process.
385  */
386 void
387 aio_proc_rundown(struct proc *p)
388 {
389 	int s;
390 	struct kaioinfo *ki;
391 	struct aio_liojob *lj, *ljn;
392 	struct aiocblist *aiocbe, *aiocbn;
393 	struct file *fp;
394 	struct filedesc *fdp;
395 	struct socket *so;
396 
397 	ki = p->p_aioinfo;
398 	if (ki == NULL)
399 		return;
400 
401 	ki->kaio_flags |= LIOJ_SIGNAL_POSTED;
402 	while ((ki->kaio_active_count > 0) || (ki->kaio_buffer_count >
403 	    ki->kaio_buffer_finished_count)) {
404 		ki->kaio_flags |= KAIO_RUNDOWN;
405 		if (tsleep(p, PRIBIO, "kaiowt", aiod_timeout))
406 			break;
407 	}
408 
409 	/*
410 	 * Move any aio ops that are waiting on socket I/O to the normal job
411 	 * queues so they are cleaned up with any others.
412 	 */
413 	fdp = p->p_fd;
414 
415 	s = splnet();
416 	for (aiocbe = TAILQ_FIRST(&ki->kaio_sockqueue); aiocbe; aiocbe =
417 	    aiocbn) {
418 		aiocbn = TAILQ_NEXT(aiocbe, plist);
419 		fp = fdp->fd_ofiles[aiocbe->uaiocb.aio_fildes];
420 
421 		/*
422 		 * Under some circumstances, the aio_fildes and the file
423 		 * structure don't match.  This would leave aiocbe's in the
424 		 * TAILQ associated with the socket and cause a panic later.
425 		 *
426 		 * Detect and fix.
427 		 */
428 		if ((fp == NULL) || (fp != aiocbe->fd_file))
429 			fp = aiocbe->fd_file;
430 		if (fp) {
431 			so = (struct socket *)fp->f_data;
432 			TAILQ_REMOVE(&so->so_aiojobq, aiocbe, list);
433 			if (TAILQ_EMPTY(&so->so_aiojobq)) {
434 				so->so_snd.sb_flags &= ~SB_AIO;
435 				so->so_rcv.sb_flags &= ~SB_AIO;
436 			}
437 		}
438 		TAILQ_REMOVE(&ki->kaio_sockqueue, aiocbe, plist);
439 		TAILQ_INSERT_HEAD(&aio_jobs, aiocbe, list);
440 		TAILQ_INSERT_HEAD(&ki->kaio_jobqueue, aiocbe, plist);
441 	}
442 	splx(s);
443 
444 restart1:
445 	for (aiocbe = TAILQ_FIRST(&ki->kaio_jobdone); aiocbe; aiocbe = aiocbn) {
446 		aiocbn = TAILQ_NEXT(aiocbe, plist);
447 		if (aio_free_entry(aiocbe))
448 			goto restart1;
449 	}
450 
451 restart2:
452 	for (aiocbe = TAILQ_FIRST(&ki->kaio_jobqueue); aiocbe; aiocbe =
453 	    aiocbn) {
454 		aiocbn = TAILQ_NEXT(aiocbe, plist);
455 		if (aio_free_entry(aiocbe))
456 			goto restart2;
457 	}
458 
459 /*
460  * Note the use of lots of splbio here, trying to avoid splbio for long chains
461  * of I/O.  Probably unnecessary.
462  */
463 restart3:
464 	s = splbio();
465 	while (TAILQ_FIRST(&ki->kaio_bufqueue)) {
466 		ki->kaio_flags |= KAIO_WAKEUP;
467 		tsleep(p, PRIBIO, "aioprn", 0);
468 		splx(s);
469 		goto restart3;
470 	}
471 	splx(s);
472 
473 restart4:
474 	s = splbio();
475 	for (aiocbe = TAILQ_FIRST(&ki->kaio_bufdone); aiocbe; aiocbe = aiocbn) {
476 		aiocbn = TAILQ_NEXT(aiocbe, plist);
477 		if (aio_free_entry(aiocbe)) {
478 			splx(s);
479 			goto restart4;
480 		}
481 	}
482 	splx(s);
483 
484 	for (lj = TAILQ_FIRST(&ki->kaio_liojoblist); lj; lj = ljn) {
485 		ljn = TAILQ_NEXT(lj, lioj_list);
486 		if ((lj->lioj_buffer_count == 0) && (lj->lioj_queue_count ==
487 		    0)) {
488 			TAILQ_REMOVE(&ki->kaio_liojoblist, lj, lioj_list);
489 			zfree(aiolio_zone, lj);
490 		} else {
491 #ifdef DIAGNOSTIC
492 			printf("LIO job not cleaned up: B:%d, BF:%d, Q:%d, "
493 			    "QF:%d\n", lj->lioj_buffer_count,
494 			    lj->lioj_buffer_finished_count,
495 			    lj->lioj_queue_count,
496 			    lj->lioj_queue_finished_count);
497 #endif
498 		}
499 	}
500 
501 	zfree(kaio_zone, ki);
502 	p->p_aioinfo = NULL;
503 }
504 
505 /*
506  * Select a job to run (called by an AIO daemon).
507  */
508 static struct aiocblist *
509 aio_selectjob(struct aioproclist *aiop)
510 {
511 	int s;
512 	struct aiocblist *aiocbe;
513 	struct kaioinfo *ki;
514 	struct proc *userp;
515 
516 	aiocbe = TAILQ_FIRST(&aiop->jobtorun);
517 	if (aiocbe) {
518 		TAILQ_REMOVE(&aiop->jobtorun, aiocbe, list);
519 		return aiocbe;
520 	}
521 
522 	s = splnet();
523 	for (aiocbe = TAILQ_FIRST(&aio_jobs); aiocbe; aiocbe =
524 	    TAILQ_NEXT(aiocbe, list)) {
525 		userp = aiocbe->userproc;
526 		ki = userp->p_aioinfo;
527 
528 		if (ki->kaio_active_count < ki->kaio_maxactive_count) {
529 			TAILQ_REMOVE(&aio_jobs, aiocbe, list);
530 			splx(s);
531 			return aiocbe;
532 		}
533 	}
534 	splx(s);
535 
536 	return NULL;
537 }
538 
539 /*
540  * The AIO processing activity.  This is the code that does the I/O request for
541  * the non-physio version of the operations.  The normal vn operations are used,
542  * and this code should work in all instances for every type of file, including
543  * pipes, sockets, fifos, and regular files.
544  */
545 void
546 aio_process(struct aiocblist *aiocbe)
547 {
548 	struct filedesc *fdp;
549 	struct proc *userp, *mycp;
550 	struct aiocb *cb;
551 	struct file *fp;
552 	struct uio auio;
553 	struct iovec aiov;
554 	unsigned int fd;
555 	int cnt;
556 	int error;
557 	off_t offset;
558 	int oublock_st, oublock_end;
559 	int inblock_st, inblock_end;
560 
561 	userp = aiocbe->userproc;
562 	cb = &aiocbe->uaiocb;
563 
564 	mycp = curproc;
565 
566 	fdp = mycp->p_fd;
567 	fd = cb->aio_fildes;
568 	fp = fdp->fd_ofiles[fd];
569 
570 	if ((fp == NULL) || (fp != aiocbe->fd_file)) {
571 		cb->_aiocb_private.error = EBADF;
572 		cb->_aiocb_private.status = -1;
573 		return;
574 	}
575 
576 	aiov.iov_base = (void *)cb->aio_buf;
577 	aiov.iov_len = cb->aio_nbytes;
578 
579 	auio.uio_iov = &aiov;
580 	auio.uio_iovcnt = 1;
581 	auio.uio_offset = offset = cb->aio_offset;
582 	auio.uio_resid = cb->aio_nbytes;
583 	cnt = cb->aio_nbytes;
584 	auio.uio_segflg = UIO_USERSPACE;
585 	auio.uio_procp = mycp;
586 
587 	inblock_st = mycp->p_stats->p_ru.ru_inblock;
588 	oublock_st = mycp->p_stats->p_ru.ru_oublock;
589 	if (cb->aio_lio_opcode == LIO_READ) {
590 		auio.uio_rw = UIO_READ;
591 		error = fo_read(fp, &auio, fp->f_cred, FOF_OFFSET, mycp);
592 	} else {
593 		auio.uio_rw = UIO_WRITE;
594 		error = fo_write(fp, &auio, fp->f_cred, FOF_OFFSET, mycp);
595 	}
596 	inblock_end = mycp->p_stats->p_ru.ru_inblock;
597 	oublock_end = mycp->p_stats->p_ru.ru_oublock;
598 
599 	aiocbe->inputcharge = inblock_end - inblock_st;
600 	aiocbe->outputcharge = oublock_end - oublock_st;
601 
602 	if ((error) && (auio.uio_resid != cnt)) {
603 		if (error == ERESTART || error == EINTR || error == EWOULDBLOCK)
604 			error = 0;
605 		if ((error == EPIPE) && (cb->aio_lio_opcode == LIO_WRITE))
606 			psignal(userp, SIGPIPE);
607 	}
608 
609 	cnt -= auio.uio_resid;
610 	cb->_aiocb_private.error = error;
611 	cb->_aiocb_private.status = cnt;
612 
613 	return;
614 }
615 
616 /*
617  * The AIO daemon, most of the actual work is done in aio_process,
618  * but the setup (and address space mgmt) is done in this routine.
619  */
620 static void
621 aio_daemon(void *uproc)
622 {
623 	int s;
624 	struct aio_liojob *lj;
625 	struct aiocb *cb;
626 	struct aiocblist *aiocbe;
627 	struct aioproclist *aiop;
628 	struct kaioinfo *ki;
629 	struct proc *curcp, *mycp, *userp;
630 	struct vmspace *myvm, *tmpvm;
631 
632 	/*
633 	 * Local copies of curproc (cp) and vmspace (myvm)
634 	 */
635 	mycp = curproc;
636 	myvm = mycp->p_vmspace;
637 
638 	if (mycp->p_textvp) {
639 		vrele(mycp->p_textvp);
640 		mycp->p_textvp = NULL;
641 	}
642 
643 	/*
644 	 * Allocate and ready the aio control info.  There is one aiop structure
645 	 * per daemon.
646 	 */
647 	aiop = zalloc(aiop_zone);
648 	aiop->aioproc = mycp;
649 	aiop->aioprocflags |= AIOP_FREE;
650 	TAILQ_INIT(&aiop->jobtorun);
651 
652 	s = splnet();
653 
654 	/*
655 	 * Place thread (lightweight process) onto the AIO free thread list.
656 	 */
657 	if (TAILQ_EMPTY(&aio_freeproc))
658 		wakeup(&aio_freeproc);
659 	TAILQ_INSERT_HEAD(&aio_freeproc, aiop, list);
660 
661 	splx(s);
662 
663 	/* Make up a name for the daemon. */
664 	strcpy(mycp->p_comm, "aiod");
665 
666 	/*
667 	 * Get rid of our current filedescriptors.  AIOD's don't need any
668 	 * filedescriptors, except as temporarily inherited from the client.
669 	 * Credentials are also cloned, and made equivalent to "root".
670 	 */
671 	fdfree(mycp);
672 	mycp->p_fd = NULL;
673 	mycp->p_ucred = crcopy(mycp->p_ucred);
674 	mycp->p_ucred->cr_uid = 0;
675 	mycp->p_ucred->cr_ngroups = 1;
676 	mycp->p_ucred->cr_groups[0] = 1;
677 
678 	/* The daemon resides in its own pgrp. */
679 	enterpgrp(mycp, mycp->p_pid, 1);
680 
681 	/* Mark special process type. */
682 	mycp->p_flag |= P_SYSTEM | P_KTHREADP;
683 
684 	/*
685 	 * Wakeup parent process.  (Parent sleeps to keep from blasting away
686 	 * creating to many daemons.)
687 	 */
688 	wakeup(mycp);
689 
690 	for (;;) {
691 		/*
692 		 * curcp is the current daemon process context.
693 		 * userp is the current user process context.
694 		 */
695 		curcp = mycp;
696 
697 		/*
698 		 * Take daemon off of free queue
699 		 */
700 		if (aiop->aioprocflags & AIOP_FREE) {
701 			s = splnet();
702 			TAILQ_REMOVE(&aio_freeproc, aiop, list);
703 			TAILQ_INSERT_TAIL(&aio_activeproc, aiop, list);
704 			aiop->aioprocflags &= ~AIOP_FREE;
705 			splx(s);
706 		}
707 		aiop->aioprocflags &= ~AIOP_SCHED;
708 
709 		/*
710 		 * Check for jobs.
711 		 */
712 		while ((aiocbe = aio_selectjob(aiop)) != NULL) {
713 			cb = &aiocbe->uaiocb;
714 			userp = aiocbe->userproc;
715 
716 			aiocbe->jobstate = JOBST_JOBRUNNING;
717 
718 			/*
719 			 * Connect to process address space for user program.
720 			 */
721 			if (userp != curcp) {
722 				/*
723 				 * Save the current address space that we are
724 				 * connected to.
725 				 */
726 				tmpvm = mycp->p_vmspace;
727 
728 				/*
729 				 * Point to the new user address space, and
730 				 * refer to it.
731 				 */
732 				mycp->p_vmspace = userp->p_vmspace;
733 				mycp->p_vmspace->vm_refcnt++;
734 
735 				/* Activate the new mapping. */
736 				pmap_activate(mycp);
737 
738 				/*
739 				 * If the old address space wasn't the daemons
740 				 * own address space, then we need to remove the
741 				 * daemon's reference from the other process
742 				 * that it was acting on behalf of.
743 				 */
744 				if (tmpvm != myvm) {
745 					vmspace_free(tmpvm);
746 				}
747 
748 				/*
749 				 * Disassociate from previous clients file
750 				 * descriptors, and associate to the new clients
751 				 * descriptors.  Note that the daemon doesn't
752 				 * need to worry about its orginal descriptors,
753 				 * because they were originally freed.
754 				 */
755 				if (mycp->p_fd)
756 					fdfree(mycp);
757 				mycp->p_fd = fdshare(userp);
758 				curcp = userp;
759 			}
760 
761 			ki = userp->p_aioinfo;
762 			lj = aiocbe->lio;
763 
764 			/* Account for currently active jobs. */
765 			ki->kaio_active_count++;
766 
767 			/* Do the I/O function. */
768 			aiocbe->jobaioproc = aiop;
769 			aio_process(aiocbe);
770 
771 			/* Decrement the active job count. */
772 			ki->kaio_active_count--;
773 
774 			/*
775 			 * Increment the completion count for wakeup/signal
776 			 * comparisons.
777 			 */
778 			aiocbe->jobflags |= AIOCBLIST_DONE;
779 			ki->kaio_queue_finished_count++;
780 			if (lj)
781 				lj->lioj_queue_finished_count++;
782 			if ((ki->kaio_flags & KAIO_WAKEUP) || ((ki->kaio_flags
783 			    & KAIO_RUNDOWN) && (ki->kaio_active_count == 0))) {
784 				ki->kaio_flags &= ~KAIO_WAKEUP;
785 				wakeup(userp);
786 			}
787 
788 			s = splbio();
789 			if (lj && (lj->lioj_flags &
790 			    (LIOJ_SIGNAL|LIOJ_SIGNAL_POSTED)) == LIOJ_SIGNAL) {
791 				if ((lj->lioj_queue_finished_count ==
792 				    lj->lioj_queue_count) &&
793 				    (lj->lioj_buffer_finished_count ==
794 				    lj->lioj_buffer_count)) {
795 						psignal(userp,
796 						    lj->lioj_signal.sigev_signo);
797 						lj->lioj_flags |=
798 						    LIOJ_SIGNAL_POSTED;
799 				}
800 			}
801 			splx(s);
802 
803 			aiocbe->jobstate = JOBST_JOBFINISHED;
804 
805 			/*
806 			 * If the I/O request should be automatically rundown,
807 			 * do the needed cleanup.  Otherwise, place the queue
808 			 * entry for the just finished I/O request into the done
809 			 * queue for the associated client.
810 			 */
811 			s = splnet();
812 			if (aiocbe->jobflags & AIOCBLIST_ASYNCFREE) {
813 				aiocbe->jobflags &= ~AIOCBLIST_ASYNCFREE;
814 				TAILQ_INSERT_HEAD(&aio_freejobs, aiocbe, list);
815 			} else {
816 				TAILQ_REMOVE(&ki->kaio_jobqueue, aiocbe, plist);
817 				TAILQ_INSERT_TAIL(&ki->kaio_jobdone, aiocbe,
818 				    plist);
819 			}
820 			splx(s);
821 			KNOTE(&aiocbe->klist, 0);
822 
823 			if (aiocbe->jobflags & AIOCBLIST_RUNDOWN) {
824 				wakeup(aiocbe);
825 				aiocbe->jobflags &= ~AIOCBLIST_RUNDOWN;
826 			}
827 
828 			if (cb->aio_sigevent.sigev_notify == SIGEV_SIGNAL) {
829 				psignal(userp, cb->aio_sigevent.sigev_signo);
830 			}
831 		}
832 
833 		/*
834 		 * Disconnect from user address space.
835 		 */
836 		if (curcp != mycp) {
837 			/* Get the user address space to disconnect from. */
838 			tmpvm = mycp->p_vmspace;
839 
840 			/* Get original address space for daemon. */
841 			mycp->p_vmspace = myvm;
842 
843 			/* Activate the daemon's address space. */
844 			pmap_activate(mycp);
845 #ifdef DIAGNOSTIC
846 			if (tmpvm == myvm) {
847 				printf("AIOD: vmspace problem -- %d\n",
848 				    mycp->p_pid);
849 			}
850 #endif
851 			/* Remove our vmspace reference. */
852 			vmspace_free(tmpvm);
853 
854 			/*
855 			 * Disassociate from the user process's file
856 			 * descriptors.
857 			 */
858 			if (mycp->p_fd)
859 				fdfree(mycp);
860 			mycp->p_fd = NULL;
861 			curcp = mycp;
862 		}
863 
864 		/*
865 		 * If we are the first to be put onto the free queue, wakeup
866 		 * anyone waiting for a daemon.
867 		 */
868 		s = splnet();
869 		TAILQ_REMOVE(&aio_activeproc, aiop, list);
870 		if (TAILQ_EMPTY(&aio_freeproc))
871 			wakeup(&aio_freeproc);
872 		TAILQ_INSERT_HEAD(&aio_freeproc, aiop, list);
873 		aiop->aioprocflags |= AIOP_FREE;
874 		splx(s);
875 
876 		/*
877 		 * If daemon is inactive for a long time, allow it to exit,
878 		 * thereby freeing resources.
879 		 */
880 		if (((aiop->aioprocflags & AIOP_SCHED) == 0) && tsleep(mycp,
881 		    PRIBIO, "aiordy", aiod_lifetime)) {
882 			s = splnet();
883 			if ((TAILQ_FIRST(&aio_jobs) == NULL) &&
884 			    (TAILQ_FIRST(&aiop->jobtorun) == NULL)) {
885 				if ((aiop->aioprocflags & AIOP_FREE) &&
886 				    (num_aio_procs > target_aio_procs)) {
887 					TAILQ_REMOVE(&aio_freeproc, aiop, list);
888 					splx(s);
889 					zfree(aiop_zone, aiop);
890 					num_aio_procs--;
891 #ifdef DIAGNOSTIC
892 					if (mycp->p_vmspace->vm_refcnt <= 1) {
893 						printf("AIOD: bad vm refcnt for"
894 						    " exiting daemon: %d\n",
895 						    mycp->p_vmspace->vm_refcnt);
896 					}
897 #endif
898 					exit1(mycp, 0);
899 				}
900 			}
901 			splx(s);
902 		}
903 	}
904 }
905 
906 /*
907  * Create a new AIO daemon.  This is mostly a kernel-thread fork routine.  The
908  * AIO daemon modifies its environment itself.
909  */
910 static int
911 aio_newproc()
912 {
913 	int error;
914 	struct proc *p, *np;
915 
916 	p = &proc0;
917 	error = fork1(p, RFPROC|RFMEM|RFNOWAIT, &np);
918 	if (error)
919 		return error;
920 	cpu_set_fork_handler(np, aio_daemon, curproc);
921 
922 	/*
923 	 * Wait until daemon is started, but continue on just in case to
924 	 * handle error conditions.
925 	 */
926 	error = tsleep(np, PZERO, "aiosta", aiod_timeout);
927 	num_aio_procs++;
928 
929 	return error;
930 }
931 
932 /*
933  * Try the high-performance physio method for eligible VCHR devices.  This
934  * routine doesn't require the use of any additional threads, and have overhead.
935  */
936 int
937 aio_qphysio(struct proc *p, struct aiocblist *aiocbe)
938 {
939 	int error;
940 	struct aiocb *cb;
941 	struct file *fp;
942 	struct buf *bp;
943 	struct vnode *vp;
944 	struct kaioinfo *ki;
945 	struct filedesc *fdp;
946 	struct aio_liojob *lj;
947 	int fd;
948 	int s;
949 	int cnt, notify;
950 
951 	cb = &aiocbe->uaiocb;
952 	fdp = p->p_fd;
953 	fd = cb->aio_fildes;
954 	fp = fdp->fd_ofiles[fd];
955 
956 	if (fp->f_type != DTYPE_VNODE)
957 		return (-1);
958 
959 	vp = (struct vnode *)fp->f_data;
960 
961 	/*
962 	 * If its not a disk, we don't want to return a positive error.
963 	 * It causes the aio code to not fall through to try the thread
964 	 * way when you're talking to a regular file.
965 	 */
966 	if (!vn_isdisk(vp, &error)) {
967 		if (error == ENOTBLK)
968 			return (-1);
969 		else
970 			return (error);
971 	}
972 
973  	if (cb->aio_nbytes % vp->v_rdev->si_bsize_phys)
974 		return (-1);
975 
976 	if ((cb->aio_nbytes > MAXPHYS) && (num_buf_aio >= max_buf_aio))
977 		return (-1);
978 
979 	ki = p->p_aioinfo;
980 	if (ki->kaio_buffer_count >= ki->kaio_ballowed_count)
981 		return (-1);
982 
983 	cnt = cb->aio_nbytes;
984 	if (cnt > MAXPHYS)
985 		return (-1);
986 
987 	/*
988 	 * Physical I/O is charged directly to the process, so we don't have to
989 	 * fake it.
990 	 */
991 	aiocbe->inputcharge = 0;
992 	aiocbe->outputcharge = 0;
993 
994 	ki->kaio_buffer_count++;
995 
996 	lj = aiocbe->lio;
997 	if (lj)
998 		lj->lioj_buffer_count++;
999 
1000 	/* Create and build a buffer header for a transfer. */
1001 	bp = (struct buf *)getpbuf(NULL);
1002 
1003 	/*
1004 	 * Get a copy of the kva from the physical buffer.
1005 	 */
1006 	bp->b_caller1 = p;
1007 	bp->b_dev = vp->v_rdev;
1008 	error = bp->b_error = 0;
1009 
1010 	bp->b_bcount = cb->aio_nbytes;
1011 	bp->b_bufsize = cb->aio_nbytes;
1012 	bp->b_flags = B_PHYS;
1013 	bp->b_iodone = aio_physwakeup;
1014 	bp->b_saveaddr = bp->b_data;
1015 	bp->b_data = (void *)cb->aio_buf;
1016 	bp->b_blkno = btodb(cb->aio_offset);
1017 
1018 	if (cb->aio_lio_opcode == LIO_WRITE) {
1019 		bp->b_iocmd = BIO_WRITE;
1020 		if (!useracc(bp->b_data, bp->b_bufsize, VM_PROT_READ)) {
1021 			error = EFAULT;
1022 			goto doerror;
1023 		}
1024 	} else {
1025 		bp->b_iocmd = BIO_READ;
1026 		if (!useracc(bp->b_data, bp->b_bufsize, VM_PROT_WRITE)) {
1027 			error = EFAULT;
1028 			goto doerror;
1029 		}
1030 	}
1031 
1032 	/* Bring buffer into kernel space. */
1033 	vmapbuf(bp);
1034 
1035 	s = splbio();
1036 	aiocbe->bp = bp;
1037 	bp->b_spc = (void *)aiocbe;
1038 	TAILQ_INSERT_TAIL(&aio_bufjobs, aiocbe, list);
1039 	TAILQ_INSERT_TAIL(&ki->kaio_bufqueue, aiocbe, plist);
1040 	aiocbe->jobstate = JOBST_JOBQBUF;
1041 	cb->_aiocb_private.status = cb->aio_nbytes;
1042 	num_buf_aio++;
1043 	bp->b_error = 0;
1044 
1045 	splx(s);
1046 
1047 	/* Perform transfer. */
1048 	DEV_STRATEGY(bp, 0);
1049 
1050 	notify = 0;
1051 	s = splbio();
1052 
1053 	/*
1054 	 * If we had an error invoking the request, or an error in processing
1055 	 * the request before we have returned, we process it as an error in
1056 	 * transfer.  Note that such an I/O error is not indicated immediately,
1057 	 * but is returned using the aio_error mechanism.  In this case,
1058 	 * aio_suspend will return immediately.
1059 	 */
1060 	if (bp->b_error || (bp->b_ioflags & BIO_ERROR)) {
1061 		struct aiocb *job = aiocbe->uuaiocb;
1062 
1063 		aiocbe->uaiocb._aiocb_private.status = 0;
1064 		suword(&job->_aiocb_private.status, 0);
1065 		aiocbe->uaiocb._aiocb_private.error = bp->b_error;
1066 		suword(&job->_aiocb_private.error, bp->b_error);
1067 
1068 		ki->kaio_buffer_finished_count++;
1069 
1070 		if (aiocbe->jobstate != JOBST_JOBBFINISHED) {
1071 			aiocbe->jobstate = JOBST_JOBBFINISHED;
1072 			aiocbe->jobflags |= AIOCBLIST_DONE;
1073 			TAILQ_REMOVE(&aio_bufjobs, aiocbe, list);
1074 			TAILQ_REMOVE(&ki->kaio_bufqueue, aiocbe, plist);
1075 			TAILQ_INSERT_TAIL(&ki->kaio_bufdone, aiocbe, plist);
1076 			notify = 1;
1077 		}
1078 	}
1079 	splx(s);
1080 	if (notify)
1081 		KNOTE(&aiocbe->klist, 0);
1082 	return 0;
1083 
1084 doerror:
1085 	ki->kaio_buffer_count--;
1086 	if (lj)
1087 		lj->lioj_buffer_count--;
1088 	aiocbe->bp = NULL;
1089 	relpbuf(bp, NULL);
1090 	return error;
1091 }
1092 
1093 /*
1094  * This waits/tests physio completion.
1095  */
1096 int
1097 aio_fphysio(struct proc *p, struct aiocblist *iocb, int flgwait)
1098 {
1099 	int s;
1100 	struct buf *bp;
1101 	int error;
1102 
1103 	bp = iocb->bp;
1104 
1105 	s = splbio();
1106 	if (flgwait == 0) {
1107 		if ((bp->b_flags & B_DONE) == 0) {
1108 			splx(s);
1109 			return EINPROGRESS;
1110 		}
1111 	}
1112 
1113 	while ((bp->b_flags & B_DONE) == 0) {
1114 		if (tsleep((caddr_t)bp, PRIBIO, "physstr", aiod_timeout)) {
1115 			if ((bp->b_flags & B_DONE) == 0) {
1116 				splx(s);
1117 				return EINPROGRESS;
1118 			} else
1119 				break;
1120 		}
1121 	}
1122 
1123 	/* Release mapping into kernel space. */
1124 	vunmapbuf(bp);
1125 	iocb->bp = 0;
1126 
1127 	error = 0;
1128 
1129 	/* Check for an error. */
1130 	if (bp->b_ioflags & BIO_ERROR)
1131 		error = bp->b_error;
1132 
1133 	relpbuf(bp, NULL);
1134 	return (error);
1135 }
1136 
1137 /*
1138  * Wake up aio requests that may be serviceable now.
1139  */
1140 void
1141 aio_swake(struct socket *so, struct sockbuf *sb)
1142 {
1143 	struct aiocblist *cb,*cbn;
1144 	struct proc *p;
1145 	struct kaioinfo *ki = NULL;
1146 	int opcode, wakecount = 0;
1147 	struct aioproclist *aiop;
1148 
1149 	if (sb == &so->so_snd) {
1150 		opcode = LIO_WRITE;
1151 		so->so_snd.sb_flags &= ~SB_AIO;
1152 	} else {
1153 		opcode = LIO_READ;
1154 		so->so_rcv.sb_flags &= ~SB_AIO;
1155 	}
1156 
1157 	for (cb = TAILQ_FIRST(&so->so_aiojobq); cb; cb = cbn) {
1158 		cbn = TAILQ_NEXT(cb, list);
1159 		if (opcode == cb->uaiocb.aio_lio_opcode) {
1160 			p = cb->userproc;
1161 			ki = p->p_aioinfo;
1162 			TAILQ_REMOVE(&so->so_aiojobq, cb, list);
1163 			TAILQ_REMOVE(&ki->kaio_sockqueue, cb, plist);
1164 			TAILQ_INSERT_TAIL(&aio_jobs, cb, list);
1165 			TAILQ_INSERT_TAIL(&ki->kaio_jobqueue, cb, plist);
1166 			wakecount++;
1167 			if (cb->jobstate != JOBST_JOBQGLOBAL)
1168 				panic("invalid queue value");
1169 		}
1170 	}
1171 
1172 	while (wakecount--) {
1173 		if ((aiop = TAILQ_FIRST(&aio_freeproc)) != 0) {
1174 			TAILQ_REMOVE(&aio_freeproc, aiop, list);
1175 			TAILQ_INSERT_TAIL(&aio_activeproc, aiop, list);
1176 			aiop->aioprocflags &= ~AIOP_FREE;
1177 			wakeup(aiop->aioproc);
1178 		}
1179 	}
1180 }
1181 
1182 /*
1183  * Queue a new AIO request.  Choosing either the threaded or direct physio VCHR
1184  * technique is done in this code.
1185  */
1186 static int
1187 _aio_aqueue(struct proc *p, struct aiocb *job, struct aio_liojob *lj, int type)
1188 {
1189 	struct filedesc *fdp;
1190 	struct file *fp;
1191 	unsigned int fd;
1192 	struct socket *so;
1193 	int s;
1194 	int error = 0;
1195 	int opcode;
1196 	struct aiocblist *aiocbe;
1197 	struct aioproclist *aiop;
1198 	struct kaioinfo *ki;
1199 
1200 	if ((aiocbe = TAILQ_FIRST(&aio_freejobs)) != NULL)
1201 		TAILQ_REMOVE(&aio_freejobs, aiocbe, list);
1202 	else
1203 		aiocbe = zalloc (aiocb_zone);
1204 
1205 	aiocbe->inputcharge = 0;
1206 	aiocbe->outputcharge = 0;
1207 	SLIST_INIT(&aiocbe->klist);
1208 
1209 	suword(&job->_aiocb_private.status, -1);
1210 	suword(&job->_aiocb_private.error, 0);
1211 	suword(&job->_aiocb_private.kernelinfo, -1);
1212 
1213 	error = copyin((caddr_t)job, (caddr_t) &aiocbe->uaiocb, sizeof
1214 	    aiocbe->uaiocb);
1215 	if (error) {
1216 		suword(&job->_aiocb_private.error, error);
1217 
1218 		TAILQ_INSERT_HEAD(&aio_freejobs, aiocbe, list);
1219 		return error;
1220 	}
1221 
1222 	/* Save userspace address of the job info. */
1223 	aiocbe->uuaiocb = job;
1224 
1225 	/* Get the opcode. */
1226 	if (type != LIO_NOP)
1227 		aiocbe->uaiocb.aio_lio_opcode = type;
1228 	opcode = aiocbe->uaiocb.aio_lio_opcode;
1229 
1230 	/* Get the fd info for process. */
1231 	fdp = p->p_fd;
1232 
1233 	/*
1234 	 * Range check file descriptor.
1235 	 */
1236 	fd = aiocbe->uaiocb.aio_fildes;
1237 	if (fd >= fdp->fd_nfiles) {
1238 		TAILQ_INSERT_HEAD(&aio_freejobs, aiocbe, list);
1239 		if (type == 0)
1240 			suword(&job->_aiocb_private.error, EBADF);
1241 		return EBADF;
1242 	}
1243 
1244 	fp = aiocbe->fd_file = fdp->fd_ofiles[fd];
1245 	if ((fp == NULL) || ((opcode == LIO_WRITE) && ((fp->f_flag & FWRITE) ==
1246 	    0))) {
1247 		TAILQ_INSERT_HEAD(&aio_freejobs, aiocbe, list);
1248 		if (type == 0)
1249 			suword(&job->_aiocb_private.error, EBADF);
1250 		return EBADF;
1251 	}
1252 
1253 	if (aiocbe->uaiocb.aio_offset == -1LL) {
1254 		TAILQ_INSERT_HEAD(&aio_freejobs, aiocbe, list);
1255 		if (type == 0)
1256 			suword(&job->_aiocb_private.error, EINVAL);
1257 		return EINVAL;
1258 	}
1259 
1260 	error = suword(&job->_aiocb_private.kernelinfo, jobrefid);
1261 	if (error) {
1262 		TAILQ_INSERT_HEAD(&aio_freejobs, aiocbe, list);
1263 		if (type == 0)
1264 			suword(&job->_aiocb_private.error, EINVAL);
1265 		return error;
1266 	}
1267 
1268 	aiocbe->uaiocb._aiocb_private.kernelinfo = (void *)(intptr_t)jobrefid;
1269 	if (jobrefid == LONG_MAX)
1270 		jobrefid = 1;
1271 	else
1272 		jobrefid++;
1273 
1274 	if (opcode == LIO_NOP) {
1275 		TAILQ_INSERT_HEAD(&aio_freejobs, aiocbe, list);
1276 		if (type == 0) {
1277 			suword(&job->_aiocb_private.error, 0);
1278 			suword(&job->_aiocb_private.status, 0);
1279 			suword(&job->_aiocb_private.kernelinfo, 0);
1280 		}
1281 		return 0;
1282 	}
1283 
1284 	if ((opcode != LIO_READ) && (opcode != LIO_WRITE)) {
1285 		TAILQ_INSERT_HEAD(&aio_freejobs, aiocbe, list);
1286 		if (type == 0) {
1287 			suword(&job->_aiocb_private.status, 0);
1288 			suword(&job->_aiocb_private.error, EINVAL);
1289 		}
1290 		return EINVAL;
1291 	}
1292 
1293 	/*
1294 	 * XXX
1295 	 * Figure out how to do this properly.  This currently won't
1296 	 * work on the alpha, since we're passing in a pointer via
1297 	 * aio_lio_opcode, which is an int.
1298 	 */
1299 	{
1300 		struct kevent kev, *kevp;
1301 		struct kqueue *kq;
1302 
1303 		kevp = (struct kevent *)job->aio_lio_opcode;
1304 		if (kevp == NULL)
1305 			goto no_kqueue;
1306 
1307 		error = copyin((caddr_t)kevp, (caddr_t)&kev, sizeof(kev));
1308 		if (error)
1309 			goto aqueue_fail;
1310 
1311 		if ((u_int)kev.ident >= fdp->fd_nfiles ||
1312 		    (fp = fdp->fd_ofiles[kev.ident]) == NULL ||
1313 		    (fp->f_type != DTYPE_KQUEUE)) {
1314 			error = EBADF;
1315 			goto aqueue_fail;
1316 		}
1317         	kq = (struct kqueue *)fp->f_data;
1318 		kev.ident = (u_long)aiocbe;
1319 		kev.filter = EVFILT_AIO;
1320 		kev.flags = EV_ADD | EV_ENABLE | EV_FLAG1;
1321 		error = kqueue_register(kq, &kev, p);
1322 aqueue_fail:
1323 		if (error) {
1324 			TAILQ_INSERT_HEAD(&aio_freejobs, aiocbe, list);
1325 			if (type == 0)
1326 				suword(&job->_aiocb_private.error, error);
1327 			return (error);
1328 		}
1329 no_kqueue:
1330 	}
1331 
1332 	suword(&job->_aiocb_private.error, EINPROGRESS);
1333 	aiocbe->uaiocb._aiocb_private.error = EINPROGRESS;
1334 	aiocbe->userproc = p;
1335 	aiocbe->jobflags = 0;
1336 	aiocbe->lio = lj;
1337 	ki = p->p_aioinfo;
1338 
1339 	if (fp->f_type == DTYPE_SOCKET) {
1340 		/*
1341 		 * Alternate queueing for socket ops: Reach down into the
1342 		 * descriptor to get the socket data.  Then check to see if the
1343 		 * socket is ready to be read or written (based on the requested
1344 		 * operation).
1345 		 *
1346 		 * If it is not ready for io, then queue the aiocbe on the
1347 		 * socket, and set the flags so we get a call when sbnotify()
1348 		 * happens.
1349 		 */
1350 		so = (struct socket *)fp->f_data;
1351 		s = splnet();
1352 		if (((opcode == LIO_READ) && (!soreadable(so))) || ((opcode ==
1353 		    LIO_WRITE) && (!sowriteable(so)))) {
1354 			TAILQ_INSERT_TAIL(&so->so_aiojobq, aiocbe, list);
1355 			TAILQ_INSERT_TAIL(&ki->kaio_sockqueue, aiocbe, plist);
1356 			if (opcode == LIO_READ)
1357 				so->so_rcv.sb_flags |= SB_AIO;
1358 			else
1359 				so->so_snd.sb_flags |= SB_AIO;
1360 			aiocbe->jobstate = JOBST_JOBQGLOBAL; /* XXX */
1361 			ki->kaio_queue_count++;
1362 			num_queue_count++;
1363 			splx(s);
1364 			return 0;
1365 		}
1366 		splx(s);
1367 	}
1368 
1369 	if ((error = aio_qphysio(p, aiocbe)) == 0)
1370 		return 0;
1371 	else if (error > 0) {
1372 		suword(&job->_aiocb_private.status, 0);
1373 		aiocbe->uaiocb._aiocb_private.error = error;
1374 		suword(&job->_aiocb_private.error, error);
1375 		return error;
1376 	}
1377 
1378 	/* No buffer for daemon I/O. */
1379 	aiocbe->bp = NULL;
1380 
1381 	ki->kaio_queue_count++;
1382 	if (lj)
1383 		lj->lioj_queue_count++;
1384 	s = splnet();
1385 	TAILQ_INSERT_TAIL(&ki->kaio_jobqueue, aiocbe, plist);
1386 	TAILQ_INSERT_TAIL(&aio_jobs, aiocbe, list);
1387 	splx(s);
1388 	aiocbe->jobstate = JOBST_JOBQGLOBAL;
1389 
1390 	num_queue_count++;
1391 	error = 0;
1392 
1393 	/*
1394 	 * If we don't have a free AIO process, and we are below our quota, then
1395 	 * start one.  Otherwise, depend on the subsequent I/O completions to
1396 	 * pick-up this job.  If we don't sucessfully create the new process
1397 	 * (thread) due to resource issues, we return an error for now (EAGAIN),
1398 	 * which is likely not the correct thing to do.
1399 	 */
1400 retryproc:
1401 	s = splnet();
1402 	if ((aiop = TAILQ_FIRST(&aio_freeproc)) != NULL) {
1403 		TAILQ_REMOVE(&aio_freeproc, aiop, list);
1404 		TAILQ_INSERT_TAIL(&aio_activeproc, aiop, list);
1405 		aiop->aioprocflags &= ~AIOP_FREE;
1406 		wakeup(aiop->aioproc);
1407 	} else if (((num_aio_resv_start + num_aio_procs) < max_aio_procs) &&
1408 	    ((ki->kaio_active_count + num_aio_resv_start) <
1409 	    ki->kaio_maxactive_count)) {
1410 		num_aio_resv_start++;
1411 		if ((error = aio_newproc()) == 0) {
1412 			num_aio_resv_start--;
1413 			p->p_retval[0] = 0;
1414 			goto retryproc;
1415 		}
1416 		num_aio_resv_start--;
1417 	}
1418 	splx(s);
1419 	return error;
1420 }
1421 
1422 /*
1423  * This routine queues an AIO request, checking for quotas.
1424  */
1425 static int
1426 aio_aqueue(struct proc *p, struct aiocb *job, int type)
1427 {
1428 	struct kaioinfo *ki;
1429 
1430 	if (p->p_aioinfo == NULL)
1431 		aio_init_aioinfo(p);
1432 
1433 	if (num_queue_count >= max_queue_count)
1434 		return EAGAIN;
1435 
1436 	ki = p->p_aioinfo;
1437 	if (ki->kaio_queue_count >= ki->kaio_qallowed_count)
1438 		return EAGAIN;
1439 
1440 	return _aio_aqueue(p, job, NULL, type);
1441 }
1442 
1443 /*
1444  * Support the aio_return system call, as a side-effect, kernel resources are
1445  * released.
1446  */
1447 int
1448 aio_return(struct proc *p, struct aio_return_args *uap)
1449 {
1450 #ifndef VFS_AIO
1451 	return ENOSYS;
1452 #else
1453 	int s;
1454 	int jobref;
1455 	struct aiocblist *cb, *ncb;
1456 	struct aiocb *ujob;
1457 	struct kaioinfo *ki;
1458 
1459 	ki = p->p_aioinfo;
1460 	if (ki == NULL)
1461 		return EINVAL;
1462 
1463 	ujob = uap->aiocbp;
1464 
1465 	jobref = fuword(&ujob->_aiocb_private.kernelinfo);
1466 	if (jobref == -1 || jobref == 0)
1467 		return EINVAL;
1468 
1469 	s = splnet();
1470 	for (cb = TAILQ_FIRST(&ki->kaio_jobdone); cb; cb = TAILQ_NEXT(cb,
1471 	    plist)) {
1472 		if (((intptr_t) cb->uaiocb._aiocb_private.kernelinfo) ==
1473 		    jobref) {
1474 			splx(s);
1475 			if (ujob == cb->uuaiocb) {
1476 				p->p_retval[0] =
1477 				    cb->uaiocb._aiocb_private.status;
1478 			} else
1479 				p->p_retval[0] = EFAULT;
1480 			if (cb->uaiocb.aio_lio_opcode == LIO_WRITE) {
1481 				curproc->p_stats->p_ru.ru_oublock +=
1482 				    cb->outputcharge;
1483 				cb->outputcharge = 0;
1484 			} else if (cb->uaiocb.aio_lio_opcode == LIO_READ) {
1485 				curproc->p_stats->p_ru.ru_inblock +=
1486 				    cb->inputcharge;
1487 				cb->inputcharge = 0;
1488 			}
1489 			aio_free_entry(cb);
1490 			return 0;
1491 		}
1492 	}
1493 	splx(s);
1494 
1495 	s = splbio();
1496 	for (cb = TAILQ_FIRST(&ki->kaio_bufdone); cb; cb = ncb) {
1497 		ncb = TAILQ_NEXT(cb, plist);
1498 		if (((intptr_t) cb->uaiocb._aiocb_private.kernelinfo)
1499 		    == jobref) {
1500 			splx(s);
1501 			if (ujob == cb->uuaiocb) {
1502 				p->p_retval[0] =
1503 				    cb->uaiocb._aiocb_private.status;
1504 			} else
1505 				p->p_retval[0] = EFAULT;
1506 			aio_free_entry(cb);
1507 			return 0;
1508 		}
1509 	}
1510 	splx(s);
1511 
1512 	return (EINVAL);
1513 #endif /* VFS_AIO */
1514 }
1515 
1516 /*
1517  * Allow a process to wakeup when any of the I/O requests are completed.
1518  */
1519 int
1520 aio_suspend(struct proc *p, struct aio_suspend_args *uap)
1521 {
1522 #ifndef VFS_AIO
1523 	return ENOSYS;
1524 #else
1525 	struct timeval atv;
1526 	struct timespec ts;
1527 	struct aiocb *const *cbptr, *cbp;
1528 	struct kaioinfo *ki;
1529 	struct aiocblist *cb;
1530 	int i;
1531 	int njoblist;
1532 	int error, s, timo;
1533 	int *ijoblist;
1534 	struct aiocb **ujoblist;
1535 
1536 	if (uap->nent >= AIO_LISTIO_MAX)
1537 		return EINVAL;
1538 
1539 	timo = 0;
1540 	if (uap->timeout) {
1541 		/* Get timespec struct. */
1542 		if ((error = copyin(uap->timeout, &ts, sizeof(ts))) != 0)
1543 			return error;
1544 
1545 		if (ts.tv_nsec < 0 || ts.tv_nsec >= 1000000000)
1546 			return (EINVAL);
1547 
1548 		TIMESPEC_TO_TIMEVAL(&atv, &ts);
1549 		if (itimerfix(&atv))
1550 			return (EINVAL);
1551 		timo = tvtohz(&atv);
1552 	}
1553 
1554 	ki = p->p_aioinfo;
1555 	if (ki == NULL)
1556 		return EAGAIN;
1557 
1558 	njoblist = 0;
1559 	ijoblist = zalloc(aiol_zone);
1560 	ujoblist = zalloc(aiol_zone);
1561 	cbptr = uap->aiocbp;
1562 
1563 	for (i = 0; i < uap->nent; i++) {
1564 		cbp = (struct aiocb *)(intptr_t)fuword((caddr_t)&cbptr[i]);
1565 		if (cbp == 0)
1566 			continue;
1567 		ujoblist[njoblist] = cbp;
1568 		ijoblist[njoblist] = fuword(&cbp->_aiocb_private.kernelinfo);
1569 		njoblist++;
1570 	}
1571 
1572 	if (njoblist == 0) {
1573 		zfree(aiol_zone, ijoblist);
1574 		zfree(aiol_zone, ujoblist);
1575 		return 0;
1576 	}
1577 
1578 	error = 0;
1579 	for (;;) {
1580 		for (cb = TAILQ_FIRST(&ki->kaio_jobdone); cb; cb =
1581 		    TAILQ_NEXT(cb, plist)) {
1582 			for (i = 0; i < njoblist; i++) {
1583 				if (((intptr_t)
1584 				    cb->uaiocb._aiocb_private.kernelinfo) ==
1585 				    ijoblist[i]) {
1586 					if (ujoblist[i] != cb->uuaiocb)
1587 						error = EINVAL;
1588 					zfree(aiol_zone, ijoblist);
1589 					zfree(aiol_zone, ujoblist);
1590 					return error;
1591 				}
1592 			}
1593 		}
1594 
1595 		s = splbio();
1596 		for (cb = TAILQ_FIRST(&ki->kaio_bufdone); cb; cb =
1597 		    TAILQ_NEXT(cb, plist)) {
1598 			for (i = 0; i < njoblist; i++) {
1599 				if (((intptr_t)
1600 				    cb->uaiocb._aiocb_private.kernelinfo) ==
1601 				    ijoblist[i]) {
1602 					splx(s);
1603 					if (ujoblist[i] != cb->uuaiocb)
1604 						error = EINVAL;
1605 					zfree(aiol_zone, ijoblist);
1606 					zfree(aiol_zone, ujoblist);
1607 					return error;
1608 				}
1609 			}
1610 		}
1611 
1612 		ki->kaio_flags |= KAIO_WAKEUP;
1613 		error = tsleep(p, PRIBIO | PCATCH, "aiospn", timo);
1614 		splx(s);
1615 
1616 		if (error == ERESTART || error == EINTR) {
1617 			zfree(aiol_zone, ijoblist);
1618 			zfree(aiol_zone, ujoblist);
1619 			return EINTR;
1620 		} else if (error == EWOULDBLOCK) {
1621 			zfree(aiol_zone, ijoblist);
1622 			zfree(aiol_zone, ujoblist);
1623 			return EAGAIN;
1624 		}
1625 	}
1626 
1627 /* NOTREACHED */
1628 	return EINVAL;
1629 #endif /* VFS_AIO */
1630 }
1631 
1632 /*
1633  * aio_cancel cancels any non-physio aio operations not currently in
1634  * progress.
1635  */
1636 int
1637 aio_cancel(struct proc *p, struct aio_cancel_args *uap)
1638 {
1639 #ifndef VFS_AIO
1640 	return ENOSYS;
1641 #else
1642 	struct kaioinfo *ki;
1643 	struct aiocblist *cbe, *cbn;
1644 	struct file *fp;
1645 	struct filedesc *fdp;
1646 	struct socket *so;
1647 	struct proc *po;
1648 	int s,error;
1649 	int cancelled=0;
1650 	int notcancelled=0;
1651 	struct vnode *vp;
1652 
1653 	fdp = p->p_fd;
1654 
1655 	fp = fdp->fd_ofiles[uap->fd];
1656 
1657 	if (fp == NULL) {
1658 		return EBADF;
1659 	}
1660 
1661         if (fp->f_type == DTYPE_VNODE) {
1662 		vp = (struct vnode *)fp->f_data;
1663 
1664 		if (vn_isdisk(vp,&error)) {
1665 			p->p_retval[0] = AIO_NOTCANCELED;
1666         	        return 0;
1667 		}
1668 	} else if (fp->f_type == DTYPE_SOCKET) {
1669 		so = (struct socket *)fp->f_data;
1670 
1671 		s = splnet();
1672 
1673 		for (cbe = TAILQ_FIRST(&so->so_aiojobq); cbe; cbe = cbn) {
1674 			cbn = TAILQ_NEXT(cbe, list);
1675 			if ((uap->aiocbp == NULL) ||
1676 				(uap->aiocbp == cbe->uuaiocb) ) {
1677 				po = cbe->userproc;
1678 				ki = po->p_aioinfo;
1679 				TAILQ_REMOVE(&so->so_aiojobq, cbe, list);
1680 				TAILQ_REMOVE(&ki->kaio_sockqueue, cbe, plist);
1681 				TAILQ_INSERT_TAIL(&ki->kaio_jobdone, cbe, plist);
1682 				if (ki->kaio_flags & KAIO_WAKEUP) {
1683 					wakeup(po);
1684 				}
1685 				cbe->jobstate = JOBST_JOBFINISHED;
1686 				cbe->uaiocb._aiocb_private.status=-1;
1687 				cbe->uaiocb._aiocb_private.error=ECANCELED;
1688 				cancelled++;
1689 /* XXX cancelled, knote? */
1690 			        if (cbe->uaiocb.aio_sigevent.sigev_notify ==
1691 				    SIGEV_SIGNAL)
1692 					psignal(cbe->userproc, cbe->uaiocb.aio_sigevent.sigev_signo);
1693 				if (uap->aiocbp)
1694 					break;
1695 			}
1696 		}
1697 
1698 		splx(s);
1699 
1700 		if ((cancelled) && (uap->aiocbp)) {
1701 			p->p_retval[0] = AIO_CANCELED;
1702 			return 0;
1703 		}
1704 
1705 	}
1706 
1707 	ki=p->p_aioinfo;
1708 
1709 	s = splnet();
1710 
1711 	for (cbe = TAILQ_FIRST(&ki->kaio_jobqueue); cbe; cbe = cbn) {
1712 		cbn = TAILQ_NEXT(cbe, plist);
1713 
1714 		if ((uap->fd == cbe->uaiocb.aio_fildes) &&
1715 		    ((uap->aiocbp == NULL ) ||
1716 		     (uap->aiocbp == cbe->uuaiocb))) {
1717 
1718 			if (cbe->jobstate == JOBST_JOBQGLOBAL) {
1719 				TAILQ_REMOVE(&aio_jobs, cbe, list);
1720                                 TAILQ_REMOVE(&ki->kaio_jobqueue, cbe, plist);
1721                                 TAILQ_INSERT_TAIL(&ki->kaio_jobdone, cbe,
1722                                     plist);
1723 				cancelled++;
1724 				ki->kaio_queue_finished_count++;
1725 				cbe->jobstate = JOBST_JOBFINISHED;
1726 				cbe->uaiocb._aiocb_private.status = -1;
1727 				cbe->uaiocb._aiocb_private.error = ECANCELED;
1728 /* XXX cancelled, knote? */
1729 			        if (cbe->uaiocb.aio_sigevent.sigev_notify ==
1730 				    SIGEV_SIGNAL)
1731 					psignal(cbe->userproc, cbe->uaiocb.aio_sigevent.sigev_signo);
1732 			} else {
1733 				notcancelled++;
1734 			}
1735 		}
1736 	}
1737 
1738 	splx(s);
1739 
1740 
1741 	if (notcancelled) {
1742 		p->p_retval[0] = AIO_NOTCANCELED;
1743 		return 0;
1744 	}
1745 
1746 	if (cancelled) {
1747 		p->p_retval[0] = AIO_CANCELED;
1748 		return 0;
1749 	}
1750 
1751 	p->p_retval[0] = AIO_ALLDONE;
1752 
1753 	return 0;
1754 #endif /* VFS_AIO */
1755 }
1756 
1757 /*
1758  * aio_error is implemented in the kernel level for compatibility purposes only.
1759  * For a user mode async implementation, it would be best to do it in a userland
1760  * subroutine.
1761  */
1762 int
1763 aio_error(struct proc *p, struct aio_error_args *uap)
1764 {
1765 #ifndef VFS_AIO
1766 	return ENOSYS;
1767 #else
1768 	int s;
1769 	struct aiocblist *cb;
1770 	struct kaioinfo *ki;
1771 	int jobref;
1772 
1773 	ki = p->p_aioinfo;
1774 	if (ki == NULL)
1775 		return EINVAL;
1776 
1777 	jobref = fuword(&uap->aiocbp->_aiocb_private.kernelinfo);
1778 	if ((jobref == -1) || (jobref == 0))
1779 		return EINVAL;
1780 
1781 	for (cb = TAILQ_FIRST(&ki->kaio_jobdone); cb; cb = TAILQ_NEXT(cb,
1782 	    plist)) {
1783 		if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo) ==
1784 		    jobref) {
1785 			p->p_retval[0] = cb->uaiocb._aiocb_private.error;
1786 			return 0;
1787 		}
1788 	}
1789 
1790 	s = splnet();
1791 
1792 	for (cb = TAILQ_FIRST(&ki->kaio_jobqueue); cb; cb = TAILQ_NEXT(cb,
1793 	    plist)) {
1794 		if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo) ==
1795 		    jobref) {
1796 			p->p_retval[0] = EINPROGRESS;
1797 			splx(s);
1798 			return 0;
1799 		}
1800 	}
1801 
1802 	for (cb = TAILQ_FIRST(&ki->kaio_sockqueue); cb; cb = TAILQ_NEXT(cb,
1803 	    plist)) {
1804 		if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo) ==
1805 		    jobref) {
1806 			p->p_retval[0] = EINPROGRESS;
1807 			splx(s);
1808 			return 0;
1809 		}
1810 	}
1811 	splx(s);
1812 
1813 	s = splbio();
1814 	for (cb = TAILQ_FIRST(&ki->kaio_bufdone); cb; cb = TAILQ_NEXT(cb,
1815 	    plist)) {
1816 		if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo) ==
1817 		    jobref) {
1818 			p->p_retval[0] = cb->uaiocb._aiocb_private.error;
1819 			splx(s);
1820 			return 0;
1821 		}
1822 	}
1823 
1824 	for (cb = TAILQ_FIRST(&ki->kaio_bufqueue); cb; cb = TAILQ_NEXT(cb,
1825 	    plist)) {
1826 		if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo) ==
1827 		    jobref) {
1828 			p->p_retval[0] = EINPROGRESS;
1829 			splx(s);
1830 			return 0;
1831 		}
1832 	}
1833 	splx(s);
1834 
1835 #if (0)
1836 	/*
1837 	 * Hack for lio.
1838 	 */
1839 	status = fuword(&uap->aiocbp->_aiocb_private.status);
1840 	if (status == -1)
1841 		return fuword(&uap->aiocbp->_aiocb_private.error);
1842 #endif
1843 	return EINVAL;
1844 #endif /* VFS_AIO */
1845 }
1846 
1847 int
1848 aio_read(struct proc *p, struct aio_read_args *uap)
1849 {
1850 #ifndef VFS_AIO
1851 	return ENOSYS;
1852 #else
1853 	struct filedesc *fdp;
1854 	struct file *fp;
1855 	struct uio auio;
1856 	struct iovec aiov;
1857 	unsigned int fd;
1858 	int cnt;
1859 	struct aiocb iocb;
1860 	int error, pmodes;
1861 
1862 	pmodes = fuword(&uap->aiocbp->_aiocb_private.privatemodes);
1863 	if ((pmodes & AIO_PMODE_SYNC) == 0)
1864 		return aio_aqueue(p, (struct aiocb *)uap->aiocbp, LIO_READ);
1865 
1866 	/* Get control block. */
1867 	if ((error = copyin((caddr_t)uap->aiocbp, (caddr_t)&iocb, sizeof iocb))
1868 	    != 0)
1869 		return error;
1870 
1871 	/* Get the fd info for process. */
1872 	fdp = p->p_fd;
1873 
1874 	/*
1875 	 * Range check file descriptor.
1876 	 */
1877 	fd = iocb.aio_fildes;
1878 	if (fd >= fdp->fd_nfiles)
1879 		return EBADF;
1880 	fp = fdp->fd_ofiles[fd];
1881 	if ((fp == NULL) || ((fp->f_flag & FREAD) == 0))
1882 		return EBADF;
1883 	if (iocb.aio_offset == -1LL)
1884 		return EINVAL;
1885 
1886 	auio.uio_resid = iocb.aio_nbytes;
1887 	if (auio.uio_resid < 0)
1888 		return (EINVAL);
1889 
1890 	/*
1891 	 * Process sync simply -- queue async request.
1892 	 */
1893 	if ((iocb._aiocb_private.privatemodes & AIO_PMODE_SYNC) == 0)
1894 		return aio_aqueue(p, (struct aiocb *)uap->aiocbp, LIO_READ);
1895 
1896 	aiov.iov_base = (void *)iocb.aio_buf;
1897 	aiov.iov_len = iocb.aio_nbytes;
1898 
1899 	auio.uio_iov = &aiov;
1900 	auio.uio_iovcnt = 1;
1901 	auio.uio_offset = iocb.aio_offset;
1902 	auio.uio_rw = UIO_READ;
1903 	auio.uio_segflg = UIO_USERSPACE;
1904 	auio.uio_procp = p;
1905 
1906 	cnt = iocb.aio_nbytes;
1907 	error = fo_read(fp, &auio, fp->f_cred, FOF_OFFSET, p);
1908 	if (error && (auio.uio_resid != cnt) && (error == ERESTART || error ==
1909 	    EINTR || error == EWOULDBLOCK))
1910 		error = 0;
1911 	cnt -= auio.uio_resid;
1912 	p->p_retval[0] = cnt;
1913 	return error;
1914 #endif /* VFS_AIO */
1915 }
1916 
1917 int
1918 aio_write(struct proc *p, struct aio_write_args *uap)
1919 {
1920 #ifndef VFS_AIO
1921 	return ENOSYS;
1922 #else
1923 	struct filedesc *fdp;
1924 	struct file *fp;
1925 	struct uio auio;
1926 	struct iovec aiov;
1927 	unsigned int fd;
1928 	int cnt;
1929 	struct aiocb iocb;
1930 	int error;
1931 	int pmodes;
1932 
1933 	/*
1934 	 * Process sync simply -- queue async request.
1935 	 */
1936 	pmodes = fuword(&uap->aiocbp->_aiocb_private.privatemodes);
1937 	if ((pmodes & AIO_PMODE_SYNC) == 0)
1938 		return aio_aqueue(p, (struct aiocb *)uap->aiocbp, LIO_WRITE);
1939 
1940 	if ((error = copyin((caddr_t)uap->aiocbp, (caddr_t)&iocb, sizeof iocb))
1941 	    != 0)
1942 		return error;
1943 
1944 	/* Get the fd info for process. */
1945 	fdp = p->p_fd;
1946 
1947 	/*
1948 	 * Range check file descriptor.
1949 	 */
1950 	fd = iocb.aio_fildes;
1951 	if (fd >= fdp->fd_nfiles)
1952 		return EBADF;
1953 	fp = fdp->fd_ofiles[fd];
1954 	if ((fp == NULL) || ((fp->f_flag & FWRITE) == 0))
1955 		return EBADF;
1956 	if (iocb.aio_offset == -1LL)
1957 		return EINVAL;
1958 
1959 	aiov.iov_base = (void *)iocb.aio_buf;
1960 	aiov.iov_len = iocb.aio_nbytes;
1961 	auio.uio_iov = &aiov;
1962 	auio.uio_iovcnt = 1;
1963 	auio.uio_offset = iocb.aio_offset;
1964 
1965 	auio.uio_resid = iocb.aio_nbytes;
1966 	if (auio.uio_resid < 0)
1967 		return (EINVAL);
1968 
1969 	auio.uio_rw = UIO_WRITE;
1970 	auio.uio_segflg = UIO_USERSPACE;
1971 	auio.uio_procp = p;
1972 
1973 	cnt = iocb.aio_nbytes;
1974 	error = fo_write(fp, &auio, fp->f_cred, FOF_OFFSET, p);
1975 	if (error) {
1976 		if (auio.uio_resid != cnt) {
1977 			if (error == ERESTART || error == EINTR || error ==
1978 			    EWOULDBLOCK)
1979 				error = 0;
1980 			if (error == EPIPE)
1981 				psignal(p, SIGPIPE);
1982 		}
1983 	}
1984 	cnt -= auio.uio_resid;
1985 	p->p_retval[0] = cnt;
1986 	return error;
1987 #endif /* VFS_AIO */
1988 }
1989 
1990 int
1991 lio_listio(struct proc *p, struct lio_listio_args *uap)
1992 {
1993 #ifndef VFS_AIO
1994 	return ENOSYS;
1995 #else
1996 	int nent, nentqueued;
1997 	struct aiocb *iocb, * const *cbptr;
1998 	struct aiocblist *cb;
1999 	struct kaioinfo *ki;
2000 	struct aio_liojob *lj;
2001 	int error, runningcode;
2002 	int nerror;
2003 	int i;
2004 	int s;
2005 
2006 	if ((uap->mode != LIO_NOWAIT) && (uap->mode != LIO_WAIT))
2007 		return EINVAL;
2008 
2009 	nent = uap->nent;
2010 	if (nent > AIO_LISTIO_MAX)
2011 		return EINVAL;
2012 
2013 	if (p->p_aioinfo == NULL)
2014 		aio_init_aioinfo(p);
2015 
2016 	if ((nent + num_queue_count) > max_queue_count)
2017 		return EAGAIN;
2018 
2019 	ki = p->p_aioinfo;
2020 	if ((nent + ki->kaio_queue_count) > ki->kaio_qallowed_count)
2021 		return EAGAIN;
2022 
2023 	lj = zalloc(aiolio_zone);
2024 	if (!lj)
2025 		return EAGAIN;
2026 
2027 	lj->lioj_flags = 0;
2028 	lj->lioj_buffer_count = 0;
2029 	lj->lioj_buffer_finished_count = 0;
2030 	lj->lioj_queue_count = 0;
2031 	lj->lioj_queue_finished_count = 0;
2032 	lj->lioj_ki = ki;
2033 	TAILQ_INSERT_TAIL(&ki->kaio_liojoblist, lj, lioj_list);
2034 
2035 	/*
2036 	 * Setup signal.
2037 	 */
2038 	if (uap->sig && (uap->mode == LIO_NOWAIT)) {
2039 		error = copyin(uap->sig, &lj->lioj_signal,
2040 		    sizeof(lj->lioj_signal));
2041 		if (error)
2042 			return error;
2043 		lj->lioj_flags |= LIOJ_SIGNAL;
2044 		lj->lioj_flags &= ~LIOJ_SIGNAL_POSTED;
2045 	} else
2046 		lj->lioj_flags &= ~LIOJ_SIGNAL;
2047 
2048 	/*
2049 	 * Get pointers to the list of I/O requests.
2050 	 */
2051 	nerror = 0;
2052 	nentqueued = 0;
2053 	cbptr = uap->acb_list;
2054 	for (i = 0; i < uap->nent; i++) {
2055 		iocb = (struct aiocb *)(intptr_t)fuword((caddr_t)&cbptr[i]);
2056 		if (((intptr_t)iocb != -1) && ((intptr_t)iocb != NULL)) {
2057 			error = _aio_aqueue(p, iocb, lj, 0);
2058 			if (error == 0)
2059 				nentqueued++;
2060 			else
2061 				nerror++;
2062 		}
2063 	}
2064 
2065 	/*
2066 	 * If we haven't queued any, then just return error.
2067 	 */
2068 	if (nentqueued == 0)
2069 		return 0;
2070 
2071 	/*
2072 	 * Calculate the appropriate error return.
2073 	 */
2074 	runningcode = 0;
2075 	if (nerror)
2076 		runningcode = EIO;
2077 
2078 	if (uap->mode == LIO_WAIT) {
2079 		int command, found, jobref;
2080 
2081 		for (;;) {
2082 			found = 0;
2083 			for (i = 0; i < uap->nent; i++) {
2084 				/*
2085 				 * Fetch address of the control buf pointer in
2086 				 * user space.
2087 				 */
2088 				iocb = (struct aiocb *)(intptr_t)fuword((caddr_t)&cbptr[i]);
2089 				if (((intptr_t)iocb == -1) || ((intptr_t)iocb
2090 				    == 0))
2091 					continue;
2092 
2093 				/*
2094 				 * Fetch the associated command from user space.
2095 				 */
2096 				command = fuword(&iocb->aio_lio_opcode);
2097 				if (command == LIO_NOP) {
2098 					found++;
2099 					continue;
2100 				}
2101 
2102 				jobref = fuword(&iocb->_aiocb_private.kernelinfo);
2103 
2104 				for (cb = TAILQ_FIRST(&ki->kaio_jobdone); cb;
2105 				    cb = TAILQ_NEXT(cb, plist)) {
2106 					if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo)
2107 					    == jobref) {
2108 						if (cb->uaiocb.aio_lio_opcode
2109 						    == LIO_WRITE) {
2110 							curproc->p_stats->p_ru.ru_oublock
2111 							    +=
2112 							    cb->outputcharge;
2113 							cb->outputcharge = 0;
2114 						} else if (cb->uaiocb.aio_lio_opcode
2115 						    == LIO_READ) {
2116 							curproc->p_stats->p_ru.ru_inblock
2117 							    += cb->inputcharge;
2118 							cb->inputcharge = 0;
2119 						}
2120 						found++;
2121 						break;
2122 					}
2123 				}
2124 
2125 				s = splbio();
2126 				for (cb = TAILQ_FIRST(&ki->kaio_bufdone); cb;
2127 				    cb = TAILQ_NEXT(cb, plist)) {
2128 					if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo)
2129 					    == jobref) {
2130 						found++;
2131 						break;
2132 					}
2133 				}
2134 				splx(s);
2135 			}
2136 
2137 			/*
2138 			 * If all I/Os have been disposed of, then we can
2139 			 * return.
2140 			 */
2141 			if (found == nentqueued)
2142 				return runningcode;
2143 
2144 			ki->kaio_flags |= KAIO_WAKEUP;
2145 			error = tsleep(p, PRIBIO | PCATCH, "aiospn", 0);
2146 
2147 			if (error == EINTR)
2148 				return EINTR;
2149 			else if (error == EWOULDBLOCK)
2150 				return EAGAIN;
2151 		}
2152 	}
2153 
2154 	return runningcode;
2155 #endif /* VFS_AIO */
2156 }
2157 
2158 /*
2159  * This is a wierd hack so that we can post a signal.  It is safe to do so from
2160  * a timeout routine, but *not* from an interrupt routine.
2161  */
2162 static void
2163 process_signal(void *aioj)
2164 {
2165 	struct aiocblist *aiocbe = aioj;
2166 	struct aio_liojob *lj = aiocbe->lio;
2167 	struct aiocb *cb = &aiocbe->uaiocb;
2168 
2169 	if ((lj) && (lj->lioj_signal.sigev_notify == SIGEV_SIGNAL) &&
2170 	    (lj->lioj_queue_count == lj->lioj_queue_finished_count)) {
2171 		psignal(lj->lioj_ki->kaio_p, lj->lioj_signal.sigev_signo);
2172 		lj->lioj_flags |= LIOJ_SIGNAL_POSTED;
2173 	}
2174 
2175 	if (cb->aio_sigevent.sigev_notify == SIGEV_SIGNAL)
2176 		psignal(aiocbe->userproc, cb->aio_sigevent.sigev_signo);
2177 }
2178 
2179 /*
2180  * Interrupt handler for physio, performs the necessary process wakeups, and
2181  * signals.
2182  */
2183 static void
2184 aio_physwakeup(struct buf *bp)
2185 {
2186 	struct aiocblist *aiocbe;
2187 	struct proc *p;
2188 	struct kaioinfo *ki;
2189 	struct aio_liojob *lj;
2190 	int s;
2191 	s = splbio();
2192 
2193 	wakeup((caddr_t)bp);
2194 	bp->b_flags |= B_DONE;
2195 
2196 	aiocbe = (struct aiocblist *)bp->b_spc;
2197 	if (aiocbe) {
2198 		p = bp->b_caller1;
2199 
2200 		aiocbe->jobstate = JOBST_JOBBFINISHED;
2201 		aiocbe->uaiocb._aiocb_private.status -= bp->b_resid;
2202 		aiocbe->uaiocb._aiocb_private.error = 0;
2203 		aiocbe->jobflags |= AIOCBLIST_DONE;
2204 
2205 		if (bp->b_ioflags & BIO_ERROR)
2206 			aiocbe->uaiocb._aiocb_private.error = bp->b_error;
2207 
2208 		lj = aiocbe->lio;
2209 		if (lj) {
2210 			lj->lioj_buffer_finished_count++;
2211 
2212 			/*
2213 			 * wakeup/signal if all of the interrupt jobs are done.
2214 			 */
2215 			if (lj->lioj_buffer_finished_count ==
2216 			    lj->lioj_buffer_count) {
2217 				/*
2218 				 * Post a signal if it is called for.
2219 				 */
2220 				if ((lj->lioj_flags &
2221 				    (LIOJ_SIGNAL|LIOJ_SIGNAL_POSTED)) ==
2222 				    LIOJ_SIGNAL) {
2223 					lj->lioj_flags |= LIOJ_SIGNAL_POSTED;
2224 					timeout(process_signal, aiocbe, 0);
2225 				}
2226 			}
2227 		}
2228 
2229 		ki = p->p_aioinfo;
2230 		if (ki) {
2231 			ki->kaio_buffer_finished_count++;
2232 			TAILQ_REMOVE(&aio_bufjobs, aiocbe, list);
2233 			TAILQ_REMOVE(&ki->kaio_bufqueue, aiocbe, plist);
2234 			TAILQ_INSERT_TAIL(&ki->kaio_bufdone, aiocbe, plist);
2235 
2236 			KNOTE(&aiocbe->klist, 0);
2237 			/* Do the wakeup. */
2238 			if (ki->kaio_flags & (KAIO_RUNDOWN|KAIO_WAKEUP)) {
2239 				ki->kaio_flags &= ~KAIO_WAKEUP;
2240 				wakeup(p);
2241 			}
2242 		}
2243 
2244 		if (aiocbe->uaiocb.aio_sigevent.sigev_notify == SIGEV_SIGNAL)
2245 			timeout(process_signal, aiocbe, 0);
2246 	}
2247 	splx(s);
2248 }
2249 
2250 int
2251 aio_waitcomplete(struct proc *p, struct aio_waitcomplete_args *uap)
2252 {
2253 #ifndef VFS_AIO
2254 	return ENOSYS;
2255 #else
2256 	struct timeval atv;
2257 	struct timespec ts;
2258 	struct aiocb **cbptr;
2259 	struct kaioinfo *ki;
2260 	struct aiocblist *cb = NULL;
2261 	int error, s, timo;
2262 
2263 	suword(uap->aiocbp, (int)NULL);
2264 
2265 	timo = 0;
2266 	if (uap->timeout) {
2267 		/* Get timespec struct. */
2268 		error = copyin((caddr_t)uap->timeout, (caddr_t)&ts,
2269 		    sizeof(ts));
2270 		if (error)
2271 			return error;
2272 
2273 		if ((ts.tv_nsec < 0) || (ts.tv_nsec >= 1000000000))
2274 			return (EINVAL);
2275 
2276 		TIMESPEC_TO_TIMEVAL(&atv, &ts);
2277 		if (itimerfix(&atv))
2278 			return (EINVAL);
2279 		timo = tvtohz(&atv);
2280 	}
2281 
2282 	ki = p->p_aioinfo;
2283 	if (ki == NULL)
2284 		return EAGAIN;
2285 
2286 	cbptr = uap->aiocbp;
2287 
2288 	for (;;) {
2289 		if ((cb = TAILQ_FIRST(&ki->kaio_jobdone)) != 0) {
2290 			suword(uap->aiocbp, (int)cb->uuaiocb);
2291 			p->p_retval[0] = cb->uaiocb._aiocb_private.status;
2292 			if (cb->uaiocb.aio_lio_opcode == LIO_WRITE) {
2293 				curproc->p_stats->p_ru.ru_oublock +=
2294 				    cb->outputcharge;
2295 				cb->outputcharge = 0;
2296 			} else if (cb->uaiocb.aio_lio_opcode == LIO_READ) {
2297 				curproc->p_stats->p_ru.ru_inblock +=
2298 				    cb->inputcharge;
2299 				cb->inputcharge = 0;
2300 			}
2301 			aio_free_entry(cb);
2302 			return cb->uaiocb._aiocb_private.error;
2303 		}
2304 
2305 		s = splbio();
2306  		if ((cb = TAILQ_FIRST(&ki->kaio_bufdone)) != 0 ) {
2307 			splx(s);
2308 			suword(uap->aiocbp, (int)cb->uuaiocb);
2309 			p->p_retval[0] = cb->uaiocb._aiocb_private.status;
2310 			aio_free_entry(cb);
2311 			return cb->uaiocb._aiocb_private.error;
2312 		}
2313 
2314 		ki->kaio_flags |= KAIO_WAKEUP;
2315 		error = tsleep(p, PRIBIO | PCATCH, "aiowc", timo);
2316 		splx(s);
2317 
2318 		if (error == ERESTART)
2319 			return EINTR;
2320 		else if (error < 0)
2321 			return error;
2322 		else if (error == EINTR)
2323 			return EINTR;
2324 		else if (error == EWOULDBLOCK)
2325 			return EAGAIN;
2326 	}
2327 #endif /* VFS_AIO */
2328 }
2329 
2330 static int
2331 filt_aioattach(struct knote *kn)
2332 {
2333 	struct aiocblist *aiocbe = (struct aiocblist *)kn->kn_id;
2334 
2335 	/*
2336 	 * The aiocbe pointer must be validated before using it, so
2337 	 * registration is restricted to the kernel; the user cannot
2338 	 * set EV_FLAG1.
2339 	 */
2340 	if ((kn->kn_flags & EV_FLAG1) == 0)
2341 		return (EPERM);
2342 	kn->kn_flags &= ~EV_FLAG1;
2343 
2344 	SLIST_INSERT_HEAD(&aiocbe->klist, kn, kn_selnext);
2345 
2346 	return (0);
2347 }
2348 
2349 static void
2350 filt_aiodetach(struct knote *kn)
2351 {
2352 	struct aiocblist *aiocbe = (struct aiocblist *)kn->kn_id;
2353 	int s = splhigh();	 /* XXX no clue, so overkill */
2354 
2355 	SLIST_REMOVE(&aiocbe->klist, kn, knote, kn_selnext);
2356 	splx(s);
2357 }
2358 
2359 /*ARGSUSED*/
2360 static int
2361 filt_aio(struct knote *kn, long hint)
2362 {
2363 	struct aiocblist *aiocbe = (struct aiocblist *)kn->kn_id;
2364 
2365 	kn->kn_data = 0;		/* XXX data returned? */
2366 	if (aiocbe->jobstate != JOBST_JOBFINISHED)
2367 		return (0);
2368 	kn->kn_flags |= EV_EOF;
2369 	return (1);
2370 }
2371