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freebsd-nq/sys/kern/vfs_aio.c
Eivind Eklund eb8e6d5276 Document all functions, global and static variables, and sysctls. 
Includes some minor whitespace changes, and re-ordering to be able to document
properly (e.g, grouping of variables and the SYSCTL macro calls for them, where
the documentation has been added.)

Reviewed by:	phk (but all errors are mine)
2002-03-05 15:38:49 +00:00

2365 lines
58 KiB
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/*
* Copyright (c) 1997 John S. Dyson. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. John S. Dyson's name may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* DISCLAIMER: This code isn't warranted to do anything useful. Anything
* bad that happens because of using this software isn't the responsibility
* of the author. This software is distributed AS-IS.
*
* $FreeBSD$
*/
/*
* This file contains support for the POSIX 1003.1B AIO/LIO facility.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/sysproto.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/unistd.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/signalvar.h>
#include <sys/protosw.h>
#include <sys/socketvar.h>
#include <sys/syscall.h>
#include <sys/sysent.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>
#include <sys/conf.h>
#include <sys/event.h>
#include <vm/vm.h>
#include <vm/vm_extern.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_zone.h>
#include <sys/aio.h>
#include <machine/limits.h>
#include "opt_vfs_aio.h"
/*
* Counter for allocating reference ids to new jobs. Wrapped to 1 on
* overflow.
*/
static long jobrefid;
#define JOBST_NULL 0x0
#define JOBST_JOBQGLOBAL 0x2
#define JOBST_JOBRUNNING 0x3
#define JOBST_JOBFINISHED 0x4
#define JOBST_JOBQBUF 0x5
#define JOBST_JOBBFINISHED 0x6
#ifndef MAX_AIO_PER_PROC
#define MAX_AIO_PER_PROC 32
#endif
#ifndef MAX_AIO_QUEUE_PER_PROC
#define MAX_AIO_QUEUE_PER_PROC 256 /* Bigger than AIO_LISTIO_MAX */
#endif
#ifndef MAX_AIO_PROCS
#define MAX_AIO_PROCS 32
#endif
#ifndef MAX_AIO_QUEUE
#define MAX_AIO_QUEUE 1024 /* Bigger than AIO_LISTIO_MAX */
#endif
#ifndef TARGET_AIO_PROCS
#define TARGET_AIO_PROCS 4
#endif
#ifndef MAX_BUF_AIO
#define MAX_BUF_AIO 16
#endif
#ifndef AIOD_TIMEOUT_DEFAULT
#define AIOD_TIMEOUT_DEFAULT (10 * hz)
#endif
#ifndef AIOD_LIFETIME_DEFAULT
#define AIOD_LIFETIME_DEFAULT (30 * hz)
#endif
SYSCTL_NODE(_vfs, OID_AUTO, aio, CTLFLAG_RW, 0, "Async IO management");
static int max_aio_procs = MAX_AIO_PROCS;
SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_procs,
CTLFLAG_RW, &max_aio_procs, 0,
"Maximum number of kernel threads to use for handling async IO ");
static int num_aio_procs = 0;
SYSCTL_INT(_vfs_aio, OID_AUTO, num_aio_procs,
CTLFLAG_RD, &num_aio_procs, 0,
"Number of presently active kernel threads for async IO");
/*
* The code will adjust the actual number of AIO processes towards this
* number when it gets a chance.
*/
static int target_aio_procs = TARGET_AIO_PROCS;
SYSCTL_INT(_vfs_aio, OID_AUTO, target_aio_procs, CTLFLAG_RW, &target_aio_procs,
0, "Preferred number of ready kernel threads for async IO");
static int max_queue_count = MAX_AIO_QUEUE;
SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_queue, CTLFLAG_RW, &max_queue_count, 0,
"Maximum number of aio requests to queue, globally");
static int num_queue_count = 0;
SYSCTL_INT(_vfs_aio, OID_AUTO, num_queue_count, CTLFLAG_RD, &num_queue_count, 0,
"Number of queued aio requests");
static int num_buf_aio = 0;
SYSCTL_INT(_vfs_aio, OID_AUTO, num_buf_aio, CTLFLAG_RD, &num_buf_aio, 0,
"Number of aio requests presently handled by the buf subsystem");
/* Number of async I/O thread in the process of being started */
/* XXX This should be local to _aio_aqueue() */
static int num_aio_resv_start = 0;
static int aiod_timeout;
SYSCTL_INT(_vfs_aio, OID_AUTO, aiod_timeout, CTLFLAG_RW, &aiod_timeout, 0,
"Timeout value for synchronous aio operations");
static int aiod_lifetime;
SYSCTL_INT(_vfs_aio, OID_AUTO, aiod_lifetime, CTLFLAG_RW, &aiod_lifetime, 0,
"Maximum lifetime for idle aiod");
static int unloadable = 0;
SYSCTL_INT(_vfs_aio, OID_AUTO, unloadable, CTLFLAG_RW, &unloadable, 0,
"Allow unload of aio (not recommended)");
static int max_aio_per_proc = MAX_AIO_PER_PROC;
SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_per_proc, CTLFLAG_RW, &max_aio_per_proc,
0, "Maximum active aio requests per process (stored in the process)");
static int max_aio_queue_per_proc = MAX_AIO_QUEUE_PER_PROC;
SYSCTL_INT(_vfs_aio, OID_AUTO, max_aio_queue_per_proc, CTLFLAG_RW,
&max_aio_queue_per_proc, 0,
"Maximum queued aio requests per process (stored in the process)");
static int max_buf_aio = MAX_BUF_AIO;
SYSCTL_INT(_vfs_aio, OID_AUTO, max_buf_aio, CTLFLAG_RW, &max_buf_aio, 0,
"Maximum buf aio requests per process (stored in the process)");
struct aiocblist {
TAILQ_ENTRY(aiocblist) list; /* List of jobs */
TAILQ_ENTRY(aiocblist) plist; /* List of jobs for proc */
int jobflags;
int jobstate;
int inputcharge;
int outputcharge;
struct callout_handle timeouthandle;
struct buf *bp; /* Buffer pointer */
struct proc *userproc; /* User process */ /* Not td! */
struct file *fd_file; /* Pointer to file structure */
struct aiothreadlist *jobaiothread; /* AIO process descriptor */
struct aio_liojob *lio; /* Optional lio job */
struct aiocb *uuaiocb; /* Pointer in userspace of aiocb */
struct klist klist; /* list of knotes */
struct aiocb uaiocb; /* Kernel I/O control block */
};
/* jobflags */
#define AIOCBLIST_RUNDOWN 0x4
#define AIOCBLIST_ASYNCFREE 0x8
#define AIOCBLIST_DONE 0x10
/*
* AIO process info
*/
#define AIOP_FREE 0x1 /* proc on free queue */
#define AIOP_SCHED 0x2 /* proc explicitly scheduled */
struct aiothreadlist {
int aiothreadflags; /* AIO proc flags */
TAILQ_ENTRY(aiothreadlist) list; /* List of processes */
struct thread *aiothread; /* The AIO thread */
};
/*
* data-structure for lio signal management
*/
struct aio_liojob {
int lioj_flags;
int lioj_buffer_count;
int lioj_buffer_finished_count;
int lioj_queue_count;
int lioj_queue_finished_count;
struct sigevent lioj_signal; /* signal on all I/O done */
TAILQ_ENTRY(aio_liojob) lioj_list;
struct kaioinfo *lioj_ki;
};
#define LIOJ_SIGNAL 0x1 /* signal on all done (lio) */
#define LIOJ_SIGNAL_POSTED 0x2 /* signal has been posted */
/*
* per process aio data structure
*/
struct kaioinfo {
int kaio_flags; /* per process kaio flags */
int kaio_maxactive_count; /* maximum number of AIOs */
int kaio_active_count; /* number of currently used AIOs */
int kaio_qallowed_count; /* maxiumu size of AIO queue */
int kaio_queue_count; /* size of AIO queue */
int kaio_ballowed_count; /* maximum number of buffers */
int kaio_queue_finished_count; /* number of daemon jobs finished */
int kaio_buffer_count; /* number of physio buffers */
int kaio_buffer_finished_count; /* count of I/O done */
struct proc *kaio_p; /* process that uses this kaio block */
TAILQ_HEAD(,aio_liojob) kaio_liojoblist; /* list of lio jobs */
TAILQ_HEAD(,aiocblist) kaio_jobqueue; /* job queue for process */
TAILQ_HEAD(,aiocblist) kaio_jobdone; /* done queue for process */
TAILQ_HEAD(,aiocblist) kaio_bufqueue; /* buffer job queue for process */
TAILQ_HEAD(,aiocblist) kaio_bufdone; /* buffer done queue for process */
TAILQ_HEAD(,aiocblist) kaio_sockqueue; /* queue for aios waiting on sockets */
};
#define KAIO_RUNDOWN 0x1 /* process is being run down */
#define KAIO_WAKEUP 0x2 /* wakeup process when there is a significant event */
static TAILQ_HEAD(,aiothreadlist) aio_activeproc; /* Active daemons */
static TAILQ_HEAD(,aiothreadlist) aio_freeproc; /* Idle daemons */
static TAILQ_HEAD(,aiocblist) aio_jobs; /* Async job list */
static TAILQ_HEAD(,aiocblist) aio_bufjobs; /* Phys I/O job list */
static void aio_init_aioinfo(struct proc *p);
static void aio_onceonly(void);
static int aio_free_entry(struct aiocblist *aiocbe);
static void aio_process(struct aiocblist *aiocbe);
static int aio_newproc(void);
static int aio_aqueue(struct thread *td, struct aiocb *job, int type);
static void aio_physwakeup(struct buf *bp);
static void aio_proc_rundown(struct proc *p);
static int aio_fphysio(struct aiocblist *aiocbe);
static int aio_qphysio(struct proc *p, struct aiocblist *iocb);
static void aio_daemon(void *uproc);
static void aio_swake_cb(struct socket *, struct sockbuf *);
static int aio_unload(void);
static void process_signal(void *aioj);
static int filt_aioattach(struct knote *kn);
static void filt_aiodetach(struct knote *kn);
static int filt_aio(struct knote *kn, long hint);
/*
* Zones for:
* kaio Per process async io info
* aiop async io thread data
* aiocb async io jobs
* aiol list io job pointer - internal to aio_suspend XXX
* aiolio list io jobs
*/
static vm_zone_t kaio_zone, aiop_zone, aiocb_zone, aiol_zone, aiolio_zone;
/* kqueue filters for aio */
static struct filterops aio_filtops =
{ 0, filt_aioattach, filt_aiodetach, filt_aio };
/*
* Main operations function for use as a kernel module.
*/
static int
aio_modload(struct module *module, int cmd, void *arg)
{
int error = 0;
switch (cmd) {
case MOD_LOAD:
aio_onceonly();
break;
case MOD_UNLOAD:
error = aio_unload();
break;
case MOD_SHUTDOWN:
break;
default:
error = EINVAL;
break;
}
return (error);
}
static moduledata_t aio_mod = {
"aio",
&aio_modload,
NULL
};
SYSCALL_MODULE_HELPER(aio_return);
SYSCALL_MODULE_HELPER(aio_suspend);
SYSCALL_MODULE_HELPER(aio_cancel);
SYSCALL_MODULE_HELPER(aio_error);
SYSCALL_MODULE_HELPER(aio_read);
SYSCALL_MODULE_HELPER(aio_write);
SYSCALL_MODULE_HELPER(aio_waitcomplete);
SYSCALL_MODULE_HELPER(lio_listio);
DECLARE_MODULE(aio, aio_mod,
SI_SUB_VFS, SI_ORDER_ANY);
MODULE_VERSION(aio, 1);
/*
* Startup initialization
*/
static void
aio_onceonly(void)
{
/* XXX: should probably just use so->callback */
aio_swake = &aio_swake_cb;
at_exit(aio_proc_rundown);
at_exec(aio_proc_rundown);
kqueue_add_filteropts(EVFILT_AIO, &aio_filtops);
TAILQ_INIT(&aio_freeproc);
TAILQ_INIT(&aio_activeproc);
TAILQ_INIT(&aio_jobs);
TAILQ_INIT(&aio_bufjobs);
kaio_zone = zinit("AIO", sizeof(struct kaioinfo), 0, 0, 1);
aiop_zone = zinit("AIOP", sizeof(struct aiothreadlist), 0, 0, 1);
aiocb_zone = zinit("AIOCB", sizeof(struct aiocblist), 0, 0, 1);
aiol_zone = zinit("AIOL", AIO_LISTIO_MAX*sizeof(intptr_t), 0, 0, 1);
aiolio_zone = zinit("AIOLIO", sizeof(struct aio_liojob), 0, 0, 1);
aiod_timeout = AIOD_TIMEOUT_DEFAULT;
aiod_lifetime = AIOD_LIFETIME_DEFAULT;
jobrefid = 1;
}
/*
* Callback for unload of AIO when used as a module.
*/
static int
aio_unload(void)
{
/*
* XXX: no unloads by default, it's too dangerous.
* perhaps we could do it if locked out callers and then
* did an aio_proc_rundown() on each process.
*/
if (!unloadable)
return (EOPNOTSUPP);
aio_swake = NULL;
rm_at_exit(aio_proc_rundown);
rm_at_exec(aio_proc_rundown);
kqueue_del_filteropts(EVFILT_AIO);
return (0);
}
/*
* Init the per-process aioinfo structure. The aioinfo limits are set
* per-process for user limit (resource) management.
*/
static void
aio_init_aioinfo(struct proc *p)
{
struct kaioinfo *ki;
if (p->p_aioinfo == NULL) {
ki = zalloc(kaio_zone);
p->p_aioinfo = ki;
ki->kaio_flags = 0;
ki->kaio_maxactive_count = max_aio_per_proc;
ki->kaio_active_count = 0;
ki->kaio_qallowed_count = max_aio_queue_per_proc;
ki->kaio_queue_count = 0;
ki->kaio_ballowed_count = max_buf_aio;
ki->kaio_buffer_count = 0;
ki->kaio_buffer_finished_count = 0;
ki->kaio_p = p;
TAILQ_INIT(&ki->kaio_jobdone);
TAILQ_INIT(&ki->kaio_jobqueue);
TAILQ_INIT(&ki->kaio_bufdone);
TAILQ_INIT(&ki->kaio_bufqueue);
TAILQ_INIT(&ki->kaio_liojoblist);
TAILQ_INIT(&ki->kaio_sockqueue);
}
while (num_aio_procs < target_aio_procs)
aio_newproc();
}
/*
* Free a job entry. Wait for completion if it is currently active, but don't
* delay forever. If we delay, we return a flag that says that we have to
* restart the queue scan.
*/
static int
aio_free_entry(struct aiocblist *aiocbe)
{
struct kaioinfo *ki;
struct aio_liojob *lj;
struct proc *p;
int error;
int s;
if (aiocbe->jobstate == JOBST_NULL)
panic("aio_free_entry: freeing already free job");
p = aiocbe->userproc;
ki = p->p_aioinfo;
lj = aiocbe->lio;
if (ki == NULL)
panic("aio_free_entry: missing p->p_aioinfo");
while (aiocbe->jobstate == JOBST_JOBRUNNING) {
if (aiocbe->jobflags & AIOCBLIST_ASYNCFREE)
return 0;
aiocbe->jobflags |= AIOCBLIST_RUNDOWN;
tsleep(aiocbe, PRIBIO, "jobwai", 0);
}
aiocbe->jobflags &= ~AIOCBLIST_ASYNCFREE;
if (aiocbe->bp == NULL) {
if (ki->kaio_queue_count <= 0)
panic("aio_free_entry: process queue size <= 0");
if (num_queue_count <= 0)
panic("aio_free_entry: system wide queue size <= 0");
if (lj) {
lj->lioj_queue_count--;
if (aiocbe->jobflags & AIOCBLIST_DONE)
lj->lioj_queue_finished_count--;
}
ki->kaio_queue_count--;
if (aiocbe->jobflags & AIOCBLIST_DONE)
ki->kaio_queue_finished_count--;
num_queue_count--;
} else {
if (lj) {
lj->lioj_buffer_count--;
if (aiocbe->jobflags & AIOCBLIST_DONE)
lj->lioj_buffer_finished_count--;
}
if (aiocbe->jobflags & AIOCBLIST_DONE)
ki->kaio_buffer_finished_count--;
ki->kaio_buffer_count--;
num_buf_aio--;
}
/* aiocbe is going away, we need to destroy any knotes */
/* XXXKSE Note the thread here is used to eventually find the
* owning process again, but it is also used to do a fo_close
* and that requires the thread. (but does it require the
* OWNING thread? (or maybe the running thread?)
* There is a semantic problem here...
*/
knote_remove(FIRST_THREAD_IN_PROC(p), &aiocbe->klist); /* XXXKSE */
if ((ki->kaio_flags & KAIO_WAKEUP) || ((ki->kaio_flags & KAIO_RUNDOWN)
&& ((ki->kaio_buffer_count == 0) && (ki->kaio_queue_count == 0)))) {
ki->kaio_flags &= ~KAIO_WAKEUP;
wakeup(p);
}
if (aiocbe->jobstate == JOBST_JOBQBUF) {
if ((error = aio_fphysio(aiocbe)) != 0)
return error;
if (aiocbe->jobstate != JOBST_JOBBFINISHED)
panic("aio_free_entry: invalid physio finish-up state");
s = splbio();
TAILQ_REMOVE(&ki->kaio_bufdone, aiocbe, plist);
splx(s);
} else if (aiocbe->jobstate == JOBST_JOBQGLOBAL) {
s = splnet();
TAILQ_REMOVE(&aio_jobs, aiocbe, list);
TAILQ_REMOVE(&ki->kaio_jobqueue, aiocbe, plist);
splx(s);
} else if (aiocbe->jobstate == JOBST_JOBFINISHED)
TAILQ_REMOVE(&ki->kaio_jobdone, aiocbe, plist);
else if (aiocbe->jobstate == JOBST_JOBBFINISHED) {
s = splbio();
TAILQ_REMOVE(&ki->kaio_bufdone, aiocbe, plist);
splx(s);
if (aiocbe->bp) {
vunmapbuf(aiocbe->bp);
relpbuf(aiocbe->bp, NULL);
aiocbe->bp = NULL;
}
}
if (lj && (lj->lioj_buffer_count == 0) && (lj->lioj_queue_count == 0)) {
TAILQ_REMOVE(&ki->kaio_liojoblist, lj, lioj_list);
zfree(aiolio_zone, lj);
}
aiocbe->jobstate = JOBST_NULL;
untimeout(process_signal, aiocbe, aiocbe->timeouthandle);
zfree(aiocb_zone, aiocbe);
return 0;
}
/*
* Rundown the jobs for a given process.
*/
static void
aio_proc_rundown(struct proc *p)
{
int s;
struct kaioinfo *ki;
struct aio_liojob *lj, *ljn;
struct aiocblist *aiocbe, *aiocbn;
struct file *fp;
struct filedesc *fdp;
struct socket *so;
ki = p->p_aioinfo;
if (ki == NULL)
return;
ki->kaio_flags |= LIOJ_SIGNAL_POSTED;
while ((ki->kaio_active_count > 0) || (ki->kaio_buffer_count >
ki->kaio_buffer_finished_count)) {
ki->kaio_flags |= KAIO_RUNDOWN;
if (tsleep(p, PRIBIO, "kaiowt", aiod_timeout))
break;
}
/*
* Move any aio ops that are waiting on socket I/O to the normal job
* queues so they are cleaned up with any others.
*/
fdp = p->p_fd;
s = splnet();
for (aiocbe = TAILQ_FIRST(&ki->kaio_sockqueue); aiocbe; aiocbe =
aiocbn) {
aiocbn = TAILQ_NEXT(aiocbe, plist);
fp = fdp->fd_ofiles[aiocbe->uaiocb.aio_fildes];
/*
* Under some circumstances, the aio_fildes and the file
* structure don't match. This would leave aiocbe's in the
* TAILQ associated with the socket and cause a panic later.
*
* Detect and fix.
*/
if ((fp == NULL) || (fp != aiocbe->fd_file))
fp = aiocbe->fd_file;
if (fp) {
so = (struct socket *)fp->f_data;
TAILQ_REMOVE(&so->so_aiojobq, aiocbe, list);
if (TAILQ_EMPTY(&so->so_aiojobq)) {
so->so_snd.sb_flags &= ~SB_AIO;
so->so_rcv.sb_flags &= ~SB_AIO;
}
}
TAILQ_REMOVE(&ki->kaio_sockqueue, aiocbe, plist);
TAILQ_INSERT_HEAD(&aio_jobs, aiocbe, list);
TAILQ_INSERT_HEAD(&ki->kaio_jobqueue, aiocbe, plist);
}
splx(s);
restart1:
for (aiocbe = TAILQ_FIRST(&ki->kaio_jobdone); aiocbe; aiocbe = aiocbn) {
aiocbn = TAILQ_NEXT(aiocbe, plist);
if (aio_free_entry(aiocbe))
goto restart1;
}
restart2:
for (aiocbe = TAILQ_FIRST(&ki->kaio_jobqueue); aiocbe; aiocbe =
aiocbn) {
aiocbn = TAILQ_NEXT(aiocbe, plist);
if (aio_free_entry(aiocbe))
goto restart2;
}
/*
* Note the use of lots of splbio here, trying to avoid splbio for long chains
* of I/O. Probably unnecessary.
*/
restart3:
s = splbio();
while (TAILQ_FIRST(&ki->kaio_bufqueue)) {
ki->kaio_flags |= KAIO_WAKEUP;
tsleep(p, PRIBIO, "aioprn", 0);
splx(s);
goto restart3;
}
splx(s);
restart4:
s = splbio();
for (aiocbe = TAILQ_FIRST(&ki->kaio_bufdone); aiocbe; aiocbe = aiocbn) {
aiocbn = TAILQ_NEXT(aiocbe, plist);
if (aio_free_entry(aiocbe)) {
splx(s);
goto restart4;
}
}
splx(s);
/*
* If we've slept, jobs might have moved from one queue to another.
* Retry rundown if we didn't manage to empty the queues.
*/
if (TAILQ_FIRST(&ki->kaio_jobdone) != NULL ||
TAILQ_FIRST(&ki->kaio_jobqueue) != NULL ||
TAILQ_FIRST(&ki->kaio_bufqueue) != NULL ||
TAILQ_FIRST(&ki->kaio_bufdone) != NULL)
goto restart1;
for (lj = TAILQ_FIRST(&ki->kaio_liojoblist); lj; lj = ljn) {
ljn = TAILQ_NEXT(lj, lioj_list);
if ((lj->lioj_buffer_count == 0) && (lj->lioj_queue_count ==
0)) {
TAILQ_REMOVE(&ki->kaio_liojoblist, lj, lioj_list);
zfree(aiolio_zone, lj);
} else {
#ifdef DIAGNOSTIC
printf("LIO job not cleaned up: B:%d, BF:%d, Q:%d, "
"QF:%d\n", lj->lioj_buffer_count,
lj->lioj_buffer_finished_count,
lj->lioj_queue_count,
lj->lioj_queue_finished_count);
#endif
}
}
zfree(kaio_zone, ki);
p->p_aioinfo = NULL;
}
/*
* Select a job to run (called by an AIO daemon).
*/
static struct aiocblist *
aio_selectjob(struct aiothreadlist *aiop)
{
int s;
struct aiocblist *aiocbe;
struct kaioinfo *ki;
struct proc *userp;
s = splnet();
for (aiocbe = TAILQ_FIRST(&aio_jobs); aiocbe; aiocbe =
TAILQ_NEXT(aiocbe, list)) {
userp = aiocbe->userproc;
ki = userp->p_aioinfo;
if (ki->kaio_active_count < ki->kaio_maxactive_count) {
TAILQ_REMOVE(&aio_jobs, aiocbe, list);
splx(s);
return aiocbe;
}
}
splx(s);
return NULL;
}
/*
* The AIO processing activity. This is the code that does the I/O request for
* the non-physio version of the operations. The normal vn operations are used,
* and this code should work in all instances for every type of file, including
* pipes, sockets, fifos, and regular files.
*/
static void
aio_process(struct aiocblist *aiocbe)
{
struct filedesc *fdp;
struct thread *td;
struct proc *userp;
struct proc *mycp;
struct aiocb *cb;
struct file *fp;
struct uio auio;
struct iovec aiov;
unsigned int fd;
int cnt;
int error;
off_t offset;
int oublock_st, oublock_end;
int inblock_st, inblock_end;
userp = aiocbe->userproc;
td = curthread;
mycp = td->td_proc;
cb = &aiocbe->uaiocb;
fdp = mycp->p_fd;
fd = cb->aio_fildes;
fp = fdp->fd_ofiles[fd];
if ((fp == NULL) || (fp != aiocbe->fd_file)) {
cb->_aiocb_private.error = EBADF;
cb->_aiocb_private.status = -1;
return;
}
aiov.iov_base = (void *)(uintptr_t)cb->aio_buf;
aiov.iov_len = cb->aio_nbytes;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = offset = cb->aio_offset;
auio.uio_resid = cb->aio_nbytes;
cnt = cb->aio_nbytes;
auio.uio_segflg = UIO_USERSPACE;
auio.uio_td = td;
inblock_st = mycp->p_stats->p_ru.ru_inblock;
oublock_st = mycp->p_stats->p_ru.ru_oublock;
/*
* Temporarily bump the ref count while reading to avoid the
* descriptor being ripped out from under us.
*/
fhold(fp);
if (cb->aio_lio_opcode == LIO_READ) {
auio.uio_rw = UIO_READ;
error = fo_read(fp, &auio, fp->f_cred, FOF_OFFSET, td);
} else {
auio.uio_rw = UIO_WRITE;
error = fo_write(fp, &auio, fp->f_cred, FOF_OFFSET, td);
}
fdrop(fp, td);
inblock_end = mycp->p_stats->p_ru.ru_inblock;
oublock_end = mycp->p_stats->p_ru.ru_oublock;
aiocbe->inputcharge = inblock_end - inblock_st;
aiocbe->outputcharge = oublock_end - oublock_st;
if ((error) && (auio.uio_resid != cnt)) {
if (error == ERESTART || error == EINTR || error == EWOULDBLOCK)
error = 0;
if ((error == EPIPE) && (cb->aio_lio_opcode == LIO_WRITE)) {
PROC_LOCK(userp);
psignal(userp, SIGPIPE);
PROC_UNLOCK(userp);
}
}
cnt -= auio.uio_resid;
cb->_aiocb_private.error = error;
cb->_aiocb_private.status = cnt;
}
/*
* The AIO daemon, most of the actual work is done in aio_process,
* but the setup (and address space mgmt) is done in this routine.
*/
static void
aio_daemon(void *uproc)
{
int s;
struct aio_liojob *lj;
struct aiocb *cb;
struct aiocblist *aiocbe;
struct aiothreadlist *aiop;
struct kaioinfo *ki;
struct proc *curcp, *mycp, *userp;
struct vmspace *myvm, *tmpvm;
struct thread *td = curthread;
struct pgrp *newpgrp;
struct session *newsess;
mtx_lock(&Giant);
/*
* Local copies of curproc (cp) and vmspace (myvm)
*/
mycp = td->td_proc;
myvm = mycp->p_vmspace;
if (mycp->p_textvp) {
vrele(mycp->p_textvp);
mycp->p_textvp = NULL;
}
/*
* Allocate and ready the aio control info. There is one aiop structure
* per daemon.
*/
aiop = zalloc(aiop_zone);
aiop->aiothread = td;
aiop->aiothreadflags |= AIOP_FREE;
s = splnet();
/*
* Place thread (lightweight process) onto the AIO free thread list.
*/
if (TAILQ_EMPTY(&aio_freeproc))
wakeup(&aio_freeproc);
TAILQ_INSERT_HEAD(&aio_freeproc, aiop, list);
splx(s);
/*
* Get rid of our current filedescriptors. AIOD's don't need any
* filedescriptors, except as temporarily inherited from the client.
*/
fdfree(td);
mycp->p_fd = NULL;
/* The daemon resides in its own pgrp. */
MALLOC(newpgrp, struct pgrp *, sizeof(struct pgrp), M_PGRP,
M_WAITOK | M_ZERO);
MALLOC(newsess, struct session *, sizeof(struct session), M_SESSION,
M_WAITOK | M_ZERO);
PGRPSESS_XLOCK();
enterpgrp(mycp, mycp->p_pid, newpgrp, newsess);
PGRPSESS_XUNLOCK();
/* Mark special process type. */
mycp->p_flag |= P_SYSTEM;
/*
* Wakeup parent process. (Parent sleeps to keep from blasting away
* and creating too many daemons.)
*/
wakeup(mycp);
for (;;) {
/*
* curcp is the current daemon process context.
* userp is the current user process context.
*/
curcp = mycp;
/*
* Take daemon off of free queue
*/
if (aiop->aiothreadflags & AIOP_FREE) {
s = splnet();
TAILQ_REMOVE(&aio_freeproc, aiop, list);
TAILQ_INSERT_TAIL(&aio_activeproc, aiop, list);
aiop->aiothreadflags &= ~AIOP_FREE;
splx(s);
}
aiop->aiothreadflags &= ~AIOP_SCHED;
/*
* Check for jobs.
*/
while ((aiocbe = aio_selectjob(aiop)) != NULL) {
cb = &aiocbe->uaiocb;
userp = aiocbe->userproc;
aiocbe->jobstate = JOBST_JOBRUNNING;
/*
* Connect to process address space for user program.
*/
if (userp != curcp) {
/*
* Save the current address space that we are
* connected to.
*/
tmpvm = mycp->p_vmspace;
/*
* Point to the new user address space, and
* refer to it.
*/
mycp->p_vmspace = userp->p_vmspace;
mycp->p_vmspace->vm_refcnt++;
/* Activate the new mapping. */
pmap_activate(FIRST_THREAD_IN_PROC(mycp));
/*
* If the old address space wasn't the daemons
* own address space, then we need to remove the
* daemon's reference from the other process
* that it was acting on behalf of.
*/
if (tmpvm != myvm) {
vmspace_free(tmpvm);
}
/*
* Disassociate from previous clients file
* descriptors, and associate to the new clients
* descriptors. Note that the daemon doesn't
* need to worry about its orginal descriptors,
* because they were originally freed.
*/
if (mycp->p_fd)
fdfree(td);
mycp->p_fd = fdshare(userp);
curcp = userp;
}
ki = userp->p_aioinfo;
lj = aiocbe->lio;
/* Account for currently active jobs. */
ki->kaio_active_count++;
/* Do the I/O function. */
aiocbe->jobaiothread = aiop;
aio_process(aiocbe);
/* Decrement the active job count. */
ki->kaio_active_count--;
/*
* Increment the completion count for wakeup/signal
* comparisons.
*/
aiocbe->jobflags |= AIOCBLIST_DONE;
ki->kaio_queue_finished_count++;
if (lj)
lj->lioj_queue_finished_count++;
if ((ki->kaio_flags & KAIO_WAKEUP) || ((ki->kaio_flags
& KAIO_RUNDOWN) && (ki->kaio_active_count == 0))) {
ki->kaio_flags &= ~KAIO_WAKEUP;
wakeup(userp);
}
s = splbio();
if (lj && (lj->lioj_flags &
(LIOJ_SIGNAL|LIOJ_SIGNAL_POSTED)) == LIOJ_SIGNAL) {
if ((lj->lioj_queue_finished_count ==
lj->lioj_queue_count) &&
(lj->lioj_buffer_finished_count ==
lj->lioj_buffer_count)) {
PROC_LOCK(userp);
psignal(userp,
lj->lioj_signal.sigev_signo);
PROC_UNLOCK(userp);
lj->lioj_flags |= LIOJ_SIGNAL_POSTED;
}
}
splx(s);
aiocbe->jobstate = JOBST_JOBFINISHED;
/*
* If the I/O request should be automatically rundown,
* do the needed cleanup. Otherwise, place the queue
* entry for the just finished I/O request into the done
* queue for the associated client.
*/
s = splnet();
if (aiocbe->jobflags & AIOCBLIST_ASYNCFREE) {
aiocbe->jobflags &= ~AIOCBLIST_ASYNCFREE;
zfree(aiocb_zone, aiocbe);
} else {
TAILQ_REMOVE(&ki->kaio_jobqueue, aiocbe, plist);
TAILQ_INSERT_TAIL(&ki->kaio_jobdone, aiocbe,
plist);
}
splx(s);
KNOTE(&aiocbe->klist, 0);
if (aiocbe->jobflags & AIOCBLIST_RUNDOWN) {
wakeup(aiocbe);
aiocbe->jobflags &= ~AIOCBLIST_RUNDOWN;
}
if (cb->aio_sigevent.sigev_notify == SIGEV_SIGNAL) {
PROC_LOCK(userp);
psignal(userp, cb->aio_sigevent.sigev_signo);
PROC_UNLOCK(userp);
}
}
/*
* Disconnect from user address space.
*/
if (curcp != mycp) {
/* Get the user address space to disconnect from. */
tmpvm = mycp->p_vmspace;
/* Get original address space for daemon. */
mycp->p_vmspace = myvm;
/* Activate the daemon's address space. */
pmap_activate(FIRST_THREAD_IN_PROC(mycp));
#ifdef DIAGNOSTIC
if (tmpvm == myvm) {
printf("AIOD: vmspace problem -- %d\n",
mycp->p_pid);
}
#endif
/* Remove our vmspace reference. */
vmspace_free(tmpvm);
/*
* Disassociate from the user process's file
* descriptors.
*/
if (mycp->p_fd)
fdfree(td);
mycp->p_fd = NULL;
curcp = mycp;
}
/*
* If we are the first to be put onto the free queue, wakeup
* anyone waiting for a daemon.
*/
s = splnet();
TAILQ_REMOVE(&aio_activeproc, aiop, list);
if (TAILQ_EMPTY(&aio_freeproc))
wakeup(&aio_freeproc);
TAILQ_INSERT_HEAD(&aio_freeproc, aiop, list);
aiop->aiothreadflags |= AIOP_FREE;
splx(s);
/*
* If daemon is inactive for a long time, allow it to exit,
* thereby freeing resources.
*/
if ((aiop->aiothreadflags & AIOP_SCHED) == 0 &&
tsleep(aiop->aiothread, PRIBIO, "aiordy", aiod_lifetime)) {
s = splnet();
if (TAILQ_EMPTY(&aio_jobs)) {
if ((aiop->aiothreadflags & AIOP_FREE) &&
(num_aio_procs > target_aio_procs)) {
TAILQ_REMOVE(&aio_freeproc, aiop, list);
splx(s);
zfree(aiop_zone, aiop);
num_aio_procs--;
#ifdef DIAGNOSTIC
if (mycp->p_vmspace->vm_refcnt <= 1) {
printf("AIOD: bad vm refcnt for"
" exiting daemon: %d\n",
mycp->p_vmspace->vm_refcnt);
}
#endif
kthread_exit(0);
}
}
splx(s);
}
}
}
/*
* Create a new AIO daemon. This is mostly a kernel-thread fork routine. The
* AIO daemon modifies its environment itself.
*/
static int
aio_newproc()
{
int error;
struct proc *p;
error = kthread_create(aio_daemon, curproc, &p, RFNOWAIT, "aiod%d",
num_aio_procs);
if (error)
return error;
/*
* Wait until daemon is started, but continue on just in case to
* handle error conditions.
*/
error = tsleep(p, PZERO, "aiosta", aiod_timeout);
num_aio_procs++;
return error;
}
/*
* Try the high-performance, low-overhead physio method for eligible
* VCHR devices. This method doesn't use an aio helper thread, and
* thus has very low overhead.
*
* Assumes that the caller, _aio_aqueue(), has incremented the file
* structure's reference count, preventing its deallocation for the
* duration of this call.
*/
static int
aio_qphysio(struct proc *p, struct aiocblist *aiocbe)
{
int error;
struct aiocb *cb;
struct file *fp;
struct buf *bp;
struct vnode *vp;
struct kaioinfo *ki;
struct aio_liojob *lj;
int s;
int notify;
cb = &aiocbe->uaiocb;
fp = aiocbe->fd_file;
if (fp->f_type != DTYPE_VNODE)
return (-1);
vp = (struct vnode *)fp->f_data;
/*
* If its not a disk, we don't want to return a positive error.
* It causes the aio code to not fall through to try the thread
* way when you're talking to a regular file.
*/
if (!vn_isdisk(vp, &error)) {
if (error == ENOTBLK)
return (-1);
else
return (error);
}
if (cb->aio_nbytes % vp->v_rdev->si_bsize_phys)
return (-1);
if (cb->aio_nbytes >
MAXPHYS - (((vm_offset_t) cb->aio_buf) & PAGE_MASK))
return (-1);
ki = p->p_aioinfo;
if (ki->kaio_buffer_count >= ki->kaio_ballowed_count)
return (-1);
ki->kaio_buffer_count++;
lj = aiocbe->lio;
if (lj)
lj->lioj_buffer_count++;
/* Create and build a buffer header for a transfer. */
bp = (struct buf *)getpbuf(NULL);
BUF_KERNPROC(bp);
/*
* Get a copy of the kva from the physical buffer.
*/
bp->b_caller1 = p;
bp->b_dev = vp->v_rdev;
error = bp->b_error = 0;
bp->b_bcount = cb->aio_nbytes;
bp->b_bufsize = cb->aio_nbytes;
bp->b_flags = B_PHYS;
bp->b_iodone = aio_physwakeup;
bp->b_saveaddr = bp->b_data;
bp->b_data = (void *)(uintptr_t)cb->aio_buf;
bp->b_blkno = btodb(cb->aio_offset);
if (cb->aio_lio_opcode == LIO_WRITE) {
bp->b_iocmd = BIO_WRITE;
if (!useracc(bp->b_data, bp->b_bufsize, VM_PROT_READ)) {
error = EFAULT;
goto doerror;
}
} else {
bp->b_iocmd = BIO_READ;
if (!useracc(bp->b_data, bp->b_bufsize, VM_PROT_WRITE)) {
error = EFAULT;
goto doerror;
}
}
/* Bring buffer into kernel space. */
vmapbuf(bp);
s = splbio();
aiocbe->bp = bp;
bp->b_spc = (void *)aiocbe;
TAILQ_INSERT_TAIL(&aio_bufjobs, aiocbe, list);
TAILQ_INSERT_TAIL(&ki->kaio_bufqueue, aiocbe, plist);
aiocbe->jobstate = JOBST_JOBQBUF;
cb->_aiocb_private.status = cb->aio_nbytes;
num_buf_aio++;
bp->b_error = 0;
splx(s);
/* Perform transfer. */
DEV_STRATEGY(bp, 0);
notify = 0;
s = splbio();
/*
* If we had an error invoking the request, or an error in processing
* the request before we have returned, we process it as an error in
* transfer. Note that such an I/O error is not indicated immediately,
* but is returned using the aio_error mechanism. In this case,
* aio_suspend will return immediately.
*/
if (bp->b_error || (bp->b_ioflags & BIO_ERROR)) {
struct aiocb *job = aiocbe->uuaiocb;
aiocbe->uaiocb._aiocb_private.status = 0;
suword(&job->_aiocb_private.status, 0);
aiocbe->uaiocb._aiocb_private.error = bp->b_error;
suword(&job->_aiocb_private.error, bp->b_error);
ki->kaio_buffer_finished_count++;
if (aiocbe->jobstate != JOBST_JOBBFINISHED) {
aiocbe->jobstate = JOBST_JOBBFINISHED;
aiocbe->jobflags |= AIOCBLIST_DONE;
TAILQ_REMOVE(&aio_bufjobs, aiocbe, list);
TAILQ_REMOVE(&ki->kaio_bufqueue, aiocbe, plist);
TAILQ_INSERT_TAIL(&ki->kaio_bufdone, aiocbe, plist);
notify = 1;
}
}
splx(s);
if (notify)
KNOTE(&aiocbe->klist, 0);
return 0;
doerror:
ki->kaio_buffer_count--;
if (lj)
lj->lioj_buffer_count--;
aiocbe->bp = NULL;
relpbuf(bp, NULL);
return error;
}
/*
* This waits/tests physio completion.
*/
static int
aio_fphysio(struct aiocblist *iocb)
{
int s;
struct buf *bp;
int error;
bp = iocb->bp;
s = splbio();
while ((bp->b_flags & B_DONE) == 0) {
if (tsleep(bp, PRIBIO, "physstr", aiod_timeout)) {
if ((bp->b_flags & B_DONE) == 0) {
splx(s);
return EINPROGRESS;
} else
break;
}
}
splx(s);
/* Release mapping into kernel space. */
vunmapbuf(bp);
iocb->bp = 0;
error = 0;
/* Check for an error. */
if (bp->b_ioflags & BIO_ERROR)
error = bp->b_error;
relpbuf(bp, NULL);
return (error);
}
/*
* Wake up aio requests that may be serviceable now.
*/
static void
aio_swake_cb(struct socket *so, struct sockbuf *sb)
{
struct aiocblist *cb,*cbn;
struct proc *p;
struct kaioinfo *ki = NULL;
int opcode, wakecount = 0;
struct aiothreadlist *aiop;
if (sb == &so->so_snd) {
opcode = LIO_WRITE;
so->so_snd.sb_flags &= ~SB_AIO;
} else {
opcode = LIO_READ;
so->so_rcv.sb_flags &= ~SB_AIO;
}
for (cb = TAILQ_FIRST(&so->so_aiojobq); cb; cb = cbn) {
cbn = TAILQ_NEXT(cb, list);
if (opcode == cb->uaiocb.aio_lio_opcode) {
p = cb->userproc;
ki = p->p_aioinfo;
TAILQ_REMOVE(&so->so_aiojobq, cb, list);
TAILQ_REMOVE(&ki->kaio_sockqueue, cb, plist);
TAILQ_INSERT_TAIL(&aio_jobs, cb, list);
TAILQ_INSERT_TAIL(&ki->kaio_jobqueue, cb, plist);
wakecount++;
if (cb->jobstate != JOBST_JOBQGLOBAL)
panic("invalid queue value");
}
}
while (wakecount--) {
if ((aiop = TAILQ_FIRST(&aio_freeproc)) != 0) {
TAILQ_REMOVE(&aio_freeproc, aiop, list);
TAILQ_INSERT_TAIL(&aio_activeproc, aiop, list);
aiop->aiothreadflags &= ~AIOP_FREE;
wakeup(aiop->aiothread);
}
}
}
/*
* Queue a new AIO request. Choosing either the threaded or direct physio VCHR
* technique is done in this code.
*/
static int
_aio_aqueue(struct thread *td, struct aiocb *job, struct aio_liojob *lj, int type)
{
struct proc *p = td->td_proc;
struct filedesc *fdp;
struct file *fp;
unsigned int fd;
struct socket *so;
int s;
int error;
int opcode;
struct aiocblist *aiocbe;
struct aiothreadlist *aiop;
struct kaioinfo *ki;
struct kevent kev;
struct kqueue *kq;
struct file *kq_fp;
aiocbe = zalloc(aiocb_zone);
aiocbe->inputcharge = 0;
aiocbe->outputcharge = 0;
callout_handle_init(&aiocbe->timeouthandle);
SLIST_INIT(&aiocbe->klist);
suword(&job->_aiocb_private.status, -1);
suword(&job->_aiocb_private.error, 0);
suword(&job->_aiocb_private.kernelinfo, -1);
error = copyin(job, &aiocbe->uaiocb, sizeof(aiocbe->uaiocb));
if (error) {
suword(&job->_aiocb_private.error, error);
zfree(aiocb_zone, aiocbe);
return error;
}
if (aiocbe->uaiocb.aio_sigevent.sigev_notify == SIGEV_SIGNAL &&
!_SIG_VALID(aiocbe->uaiocb.aio_sigevent.sigev_signo)) {
zfree(aiocb_zone, aiocbe);
return EINVAL;
}
/* Save userspace address of the job info. */
aiocbe->uuaiocb = job;
/* Get the opcode. */
if (type != LIO_NOP)
aiocbe->uaiocb.aio_lio_opcode = type;
opcode = aiocbe->uaiocb.aio_lio_opcode;
/* Get the fd info for process. */
fdp = p->p_fd;
/*
* Range check file descriptor.
*/
fd = aiocbe->uaiocb.aio_fildes;
if (fd >= fdp->fd_nfiles) {
zfree(aiocb_zone, aiocbe);
if (type == 0)
suword(&job->_aiocb_private.error, EBADF);
return EBADF;
}
fp = aiocbe->fd_file = fdp->fd_ofiles[fd];
if ((fp == NULL) || ((opcode == LIO_WRITE) && ((fp->f_flag & FWRITE) ==
0))) {
zfree(aiocb_zone, aiocbe);
if (type == 0)
suword(&job->_aiocb_private.error, EBADF);
return EBADF;
}
if (aiocbe->uaiocb.aio_offset == -1LL) {
zfree(aiocb_zone, aiocbe);
if (type == 0)
suword(&job->_aiocb_private.error, EINVAL);
return EINVAL;
}
error = suword(&job->_aiocb_private.kernelinfo, jobrefid);
if (error) {
zfree(aiocb_zone, aiocbe);
if (type == 0)
suword(&job->_aiocb_private.error, EINVAL);
return error;
}
aiocbe->uaiocb._aiocb_private.kernelinfo = (void *)(intptr_t)jobrefid;
if (jobrefid == LONG_MAX)
jobrefid = 1;
else
jobrefid++;
if (opcode == LIO_NOP) {
zfree(aiocb_zone, aiocbe);
if (type == 0) {
suword(&job->_aiocb_private.error, 0);
suword(&job->_aiocb_private.status, 0);
suword(&job->_aiocb_private.kernelinfo, 0);
}
return 0;
}
if ((opcode != LIO_READ) && (opcode != LIO_WRITE)) {
zfree(aiocb_zone, aiocbe);
if (type == 0) {
suword(&job->_aiocb_private.status, 0);
suword(&job->_aiocb_private.error, EINVAL);
}
return EINVAL;
}
fhold(fp);
if (aiocbe->uaiocb.aio_sigevent.sigev_notify == SIGEV_KEVENT) {
kev.ident = aiocbe->uaiocb.aio_sigevent.sigev_notify_kqueue;
kev.udata = aiocbe->uaiocb.aio_sigevent.sigev_value.sigval_ptr;
}
else {
/*
* This method for requesting kevent-based notification won't
* work on the alpha, since we're passing in a pointer
* via aio_lio_opcode, which is an int. Use the SIGEV_KEVENT-
* based method instead.
*/
struct kevent *kevp;
kevp = (struct kevent *)(uintptr_t)job->aio_lio_opcode;
if (kevp == NULL)
goto no_kqueue;
error = copyin(kevp, &kev, sizeof(kev));
if (error)
goto aqueue_fail;
}
if ((u_int)kev.ident >= fdp->fd_nfiles ||
(kq_fp = fdp->fd_ofiles[kev.ident]) == NULL ||
(kq_fp->f_type != DTYPE_KQUEUE)) {
error = EBADF;
goto aqueue_fail;
}
kq = (struct kqueue *)kq_fp->f_data;
kev.ident = (uintptr_t)aiocbe;
kev.filter = EVFILT_AIO;
kev.flags = EV_ADD | EV_ENABLE | EV_FLAG1;
error = kqueue_register(kq, &kev, td);
aqueue_fail:
if (error) {
zfree(aiocb_zone, aiocbe);
if (type == 0)
suword(&job->_aiocb_private.error, error);
goto done;
}
no_kqueue:
suword(&job->_aiocb_private.error, EINPROGRESS);
aiocbe->uaiocb._aiocb_private.error = EINPROGRESS;
aiocbe->userproc = p;
aiocbe->jobflags = 0;
aiocbe->lio = lj;
ki = p->p_aioinfo;
if (fp->f_type == DTYPE_SOCKET) {
/*
* Alternate queueing for socket ops: Reach down into the
* descriptor to get the socket data. Then check to see if the
* socket is ready to be read or written (based on the requested
* operation).
*
* If it is not ready for io, then queue the aiocbe on the
* socket, and set the flags so we get a call when sbnotify()
* happens.
*/
so = (struct socket *)fp->f_data;
s = splnet();
if (((opcode == LIO_READ) && (!soreadable(so))) || ((opcode ==
LIO_WRITE) && (!sowriteable(so)))) {
TAILQ_INSERT_TAIL(&so->so_aiojobq, aiocbe, list);
TAILQ_INSERT_TAIL(&ki->kaio_sockqueue, aiocbe, plist);
if (opcode == LIO_READ)
so->so_rcv.sb_flags |= SB_AIO;
else
so->so_snd.sb_flags |= SB_AIO;
aiocbe->jobstate = JOBST_JOBQGLOBAL; /* XXX */
ki->kaio_queue_count++;
num_queue_count++;
splx(s);
error = 0;
goto done;
}
splx(s);
}
if ((error = aio_qphysio(p, aiocbe)) == 0)
goto done;
if (error > 0) {
suword(&job->_aiocb_private.status, 0);
aiocbe->uaiocb._aiocb_private.error = error;
suword(&job->_aiocb_private.error, error);
goto done;
}
/* No buffer for daemon I/O. */
aiocbe->bp = NULL;
ki->kaio_queue_count++;
if (lj)
lj->lioj_queue_count++;
s = splnet();
TAILQ_INSERT_TAIL(&ki->kaio_jobqueue, aiocbe, plist);
TAILQ_INSERT_TAIL(&aio_jobs, aiocbe, list);
splx(s);
aiocbe->jobstate = JOBST_JOBQGLOBAL;
num_queue_count++;
error = 0;
/*
* If we don't have a free AIO process, and we are below our quota, then
* start one. Otherwise, depend on the subsequent I/O completions to
* pick-up this job. If we don't sucessfully create the new process
* (thread) due to resource issues, we return an error for now (EAGAIN),
* which is likely not the correct thing to do.
*/
s = splnet();
retryproc:
if ((aiop = TAILQ_FIRST(&aio_freeproc)) != NULL) {
TAILQ_REMOVE(&aio_freeproc, aiop, list);
TAILQ_INSERT_TAIL(&aio_activeproc, aiop, list);
aiop->aiothreadflags &= ~AIOP_FREE;
wakeup(aiop->aiothread);
} else if (((num_aio_resv_start + num_aio_procs) < max_aio_procs) &&
((ki->kaio_active_count + num_aio_resv_start) <
ki->kaio_maxactive_count)) {
num_aio_resv_start++;
if ((error = aio_newproc()) == 0) {
num_aio_resv_start--;
goto retryproc;
}
num_aio_resv_start--;
}
splx(s);
done:
fdrop(fp, td);
return error;
}
/*
* This routine queues an AIO request, checking for quotas.
*/
static int
aio_aqueue(struct thread *td, struct aiocb *job, int type)
{
struct proc *p = td->td_proc;
struct kaioinfo *ki;
if (p->p_aioinfo == NULL)
aio_init_aioinfo(p);
if (num_queue_count >= max_queue_count)
return EAGAIN;
ki = p->p_aioinfo;
if (ki->kaio_queue_count >= ki->kaio_qallowed_count)
return EAGAIN;
return _aio_aqueue(td, job, NULL, type);
}
/*
* Support the aio_return system call, as a side-effect, kernel resources are
* released.
*/
int
aio_return(struct thread *td, struct aio_return_args *uap)
{
struct proc *p = td->td_proc;
int s;
int jobref;
struct aiocblist *cb, *ncb;
struct aiocb *ujob;
struct kaioinfo *ki;
ki = p->p_aioinfo;
if (ki == NULL)
return EINVAL;
ujob = uap->aiocbp;
jobref = fuword(&ujob->_aiocb_private.kernelinfo);
if (jobref == -1 || jobref == 0)
return EINVAL;
TAILQ_FOREACH(cb, &ki->kaio_jobdone, plist) {
if (((intptr_t) cb->uaiocb._aiocb_private.kernelinfo) ==
jobref) {
if (ujob == cb->uuaiocb) {
td->td_retval[0] =
cb->uaiocb._aiocb_private.status;
} else
td->td_retval[0] = EFAULT;
if (cb->uaiocb.aio_lio_opcode == LIO_WRITE) {
p->p_stats->p_ru.ru_oublock +=
cb->outputcharge;
cb->outputcharge = 0;
} else if (cb->uaiocb.aio_lio_opcode == LIO_READ) {
p->p_stats->p_ru.ru_inblock += cb->inputcharge;
cb->inputcharge = 0;
}
aio_free_entry(cb);
return 0;
}
}
s = splbio();
for (cb = TAILQ_FIRST(&ki->kaio_bufdone); cb; cb = ncb) {
ncb = TAILQ_NEXT(cb, plist);
if (((intptr_t) cb->uaiocb._aiocb_private.kernelinfo)
== jobref) {
splx(s);
if (ujob == cb->uuaiocb) {
td->td_retval[0] =
cb->uaiocb._aiocb_private.status;
} else
td->td_retval[0] = EFAULT;
aio_free_entry(cb);
return 0;
}
}
splx(s);
return (EINVAL);
}
/*
* Allow a process to wakeup when any of the I/O requests are completed.
*/
int
aio_suspend(struct thread *td, struct aio_suspend_args *uap)
{
struct proc *p = td->td_proc;
struct timeval atv;
struct timespec ts;
struct aiocb *const *cbptr, *cbp;
struct kaioinfo *ki;
struct aiocblist *cb;
int i;
int njoblist;
int error, s, timo;
int *ijoblist;
struct aiocb **ujoblist;
if (uap->nent > AIO_LISTIO_MAX)
return EINVAL;
timo = 0;
if (uap->timeout) {
/* Get timespec struct. */
if ((error = copyin(uap->timeout, &ts, sizeof(ts))) != 0)
return error;
if (ts.tv_nsec < 0 || ts.tv_nsec >= 1000000000)
return (EINVAL);
TIMESPEC_TO_TIMEVAL(&atv, &ts);
if (itimerfix(&atv))
return (EINVAL);
timo = tvtohz(&atv);
}
ki = p->p_aioinfo;
if (ki == NULL)
return EAGAIN;
njoblist = 0;
ijoblist = zalloc(aiol_zone);
ujoblist = zalloc(aiol_zone);
cbptr = uap->aiocbp;
for (i = 0; i < uap->nent; i++) {
cbp = (struct aiocb *)(intptr_t)fuword((caddr_t)&cbptr[i]);
if (cbp == 0)
continue;
ujoblist[njoblist] = cbp;
ijoblist[njoblist] = fuword(&cbp->_aiocb_private.kernelinfo);
njoblist++;
}
if (njoblist == 0) {
zfree(aiol_zone, ijoblist);
zfree(aiol_zone, ujoblist);
return 0;
}
error = 0;
for (;;) {
TAILQ_FOREACH(cb, &ki->kaio_jobdone, plist) {
for (i = 0; i < njoblist; i++) {
if (((intptr_t)
cb->uaiocb._aiocb_private.kernelinfo) ==
ijoblist[i]) {
if (ujoblist[i] != cb->uuaiocb)
error = EINVAL;
zfree(aiol_zone, ijoblist);
zfree(aiol_zone, ujoblist);
return error;
}
}
}
s = splbio();
for (cb = TAILQ_FIRST(&ki->kaio_bufdone); cb; cb =
TAILQ_NEXT(cb, plist)) {
for (i = 0; i < njoblist; i++) {
if (((intptr_t)
cb->uaiocb._aiocb_private.kernelinfo) ==
ijoblist[i]) {
splx(s);
if (ujoblist[i] != cb->uuaiocb)
error = EINVAL;
zfree(aiol_zone, ijoblist);
zfree(aiol_zone, ujoblist);
return error;
}
}
}
ki->kaio_flags |= KAIO_WAKEUP;
error = tsleep(p, PRIBIO | PCATCH, "aiospn", timo);
splx(s);
if (error == ERESTART || error == EINTR) {
zfree(aiol_zone, ijoblist);
zfree(aiol_zone, ujoblist);
return EINTR;
} else if (error == EWOULDBLOCK) {
zfree(aiol_zone, ijoblist);
zfree(aiol_zone, ujoblist);
return EAGAIN;
}
}
/* NOTREACHED */
return EINVAL;
}
/*
* aio_cancel cancels any non-physio aio operations not currently in
* progress.
*/
int
aio_cancel(struct thread *td, struct aio_cancel_args *uap)
{
struct proc *p = td->td_proc;
struct kaioinfo *ki;
struct aiocblist *cbe, *cbn;
struct file *fp;
struct filedesc *fdp;
struct socket *so;
struct proc *po;
int s,error;
int cancelled=0;
int notcancelled=0;
struct vnode *vp;
fdp = p->p_fd;
if ((u_int)uap->fd >= fdp->fd_nfiles ||
(fp = fdp->fd_ofiles[uap->fd]) == NULL)
return (EBADF);
if (fp->f_type == DTYPE_VNODE) {
vp = (struct vnode *)fp->f_data;
if (vn_isdisk(vp,&error)) {
td->td_retval[0] = AIO_NOTCANCELED;
return 0;
}
} else if (fp->f_type == DTYPE_SOCKET) {
so = (struct socket *)fp->f_data;
s = splnet();
for (cbe = TAILQ_FIRST(&so->so_aiojobq); cbe; cbe = cbn) {
cbn = TAILQ_NEXT(cbe, list);
if ((uap->aiocbp == NULL) ||
(uap->aiocbp == cbe->uuaiocb) ) {
po = cbe->userproc;
ki = po->p_aioinfo;
TAILQ_REMOVE(&so->so_aiojobq, cbe, list);
TAILQ_REMOVE(&ki->kaio_sockqueue, cbe, plist);
TAILQ_INSERT_TAIL(&ki->kaio_jobdone, cbe, plist);
if (ki->kaio_flags & KAIO_WAKEUP) {
wakeup(po);
}
cbe->jobstate = JOBST_JOBFINISHED;
cbe->uaiocb._aiocb_private.status=-1;
cbe->uaiocb._aiocb_private.error=ECANCELED;
cancelled++;
/* XXX cancelled, knote? */
if (cbe->uaiocb.aio_sigevent.sigev_notify ==
SIGEV_SIGNAL) {
PROC_LOCK(cbe->userproc);
psignal(cbe->userproc, cbe->uaiocb.aio_sigevent.sigev_signo);
PROC_UNLOCK(cbe->userproc);
}
if (uap->aiocbp)
break;
}
}
splx(s);
if ((cancelled) && (uap->aiocbp)) {
td->td_retval[0] = AIO_CANCELED;
return 0;
}
}
ki=p->p_aioinfo;
s = splnet();
for (cbe = TAILQ_FIRST(&ki->kaio_jobqueue); cbe; cbe = cbn) {
cbn = TAILQ_NEXT(cbe, plist);
if ((uap->fd == cbe->uaiocb.aio_fildes) &&
((uap->aiocbp == NULL ) ||
(uap->aiocbp == cbe->uuaiocb))) {
if (cbe->jobstate == JOBST_JOBQGLOBAL) {
TAILQ_REMOVE(&aio_jobs, cbe, list);
TAILQ_REMOVE(&ki->kaio_jobqueue, cbe, plist);
TAILQ_INSERT_TAIL(&ki->kaio_jobdone, cbe,
plist);
cancelled++;
ki->kaio_queue_finished_count++;
cbe->jobstate = JOBST_JOBFINISHED;
cbe->uaiocb._aiocb_private.status = -1;
cbe->uaiocb._aiocb_private.error = ECANCELED;
/* XXX cancelled, knote? */
if (cbe->uaiocb.aio_sigevent.sigev_notify ==
SIGEV_SIGNAL) {
PROC_LOCK(cbe->userproc);
psignal(cbe->userproc, cbe->uaiocb.aio_sigevent.sigev_signo);
PROC_UNLOCK(cbe->userproc);
}
} else {
notcancelled++;
}
}
}
splx(s);
if (notcancelled) {
td->td_retval[0] = AIO_NOTCANCELED;
return 0;
}
if (cancelled) {
td->td_retval[0] = AIO_CANCELED;
return 0;
}
td->td_retval[0] = AIO_ALLDONE;
return 0;
}
/*
* aio_error is implemented in the kernel level for compatibility purposes only.
* For a user mode async implementation, it would be best to do it in a userland
* subroutine.
*/
int
aio_error(struct thread *td, struct aio_error_args *uap)
{
struct proc *p = td->td_proc;
int s;
struct aiocblist *cb;
struct kaioinfo *ki;
int jobref;
ki = p->p_aioinfo;
if (ki == NULL)
return EINVAL;
jobref = fuword(&uap->aiocbp->_aiocb_private.kernelinfo);
if ((jobref == -1) || (jobref == 0))
return EINVAL;
TAILQ_FOREACH(cb, &ki->kaio_jobdone, plist) {
if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo) ==
jobref) {
td->td_retval[0] = cb->uaiocb._aiocb_private.error;
return 0;
}
}
s = splnet();
for (cb = TAILQ_FIRST(&ki->kaio_jobqueue); cb; cb = TAILQ_NEXT(cb,
plist)) {
if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo) ==
jobref) {
td->td_retval[0] = EINPROGRESS;
splx(s);
return 0;
}
}
for (cb = TAILQ_FIRST(&ki->kaio_sockqueue); cb; cb = TAILQ_NEXT(cb,
plist)) {
if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo) ==
jobref) {
td->td_retval[0] = EINPROGRESS;
splx(s);
return 0;
}
}
splx(s);
s = splbio();
for (cb = TAILQ_FIRST(&ki->kaio_bufdone); cb; cb = TAILQ_NEXT(cb,
plist)) {
if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo) ==
jobref) {
td->td_retval[0] = cb->uaiocb._aiocb_private.error;
splx(s);
return 0;
}
}
for (cb = TAILQ_FIRST(&ki->kaio_bufqueue); cb; cb = TAILQ_NEXT(cb,
plist)) {
if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo) ==
jobref) {
td->td_retval[0] = EINPROGRESS;
splx(s);
return 0;
}
}
splx(s);
#if (0)
/*
* Hack for lio.
*/
status = fuword(&uap->aiocbp->_aiocb_private.status);
if (status == -1)
return fuword(&uap->aiocbp->_aiocb_private.error);
#endif
return EINVAL;
}
/* syscall - asynchronous read from a file (REALTIME) */
int
aio_read(struct thread *td, struct aio_read_args *uap)
{
return aio_aqueue(td, uap->aiocbp, LIO_READ);
}
/* syscall - asynchronous write to a file (REALTIME) */
int
aio_write(struct thread *td, struct aio_write_args *uap)
{
return aio_aqueue(td, uap->aiocbp, LIO_WRITE);
}
/* syscall - XXX undocumented */
int
lio_listio(struct thread *td, struct lio_listio_args *uap)
{
struct proc *p = td->td_proc;
int nent, nentqueued;
struct aiocb *iocb, * const *cbptr;
struct aiocblist *cb;
struct kaioinfo *ki;
struct aio_liojob *lj;
int error, runningcode;
int nerror;
int i;
int s;
if ((uap->mode != LIO_NOWAIT) && (uap->mode != LIO_WAIT))
return EINVAL;
nent = uap->nent;
if (nent > AIO_LISTIO_MAX)
return EINVAL;
if (p->p_aioinfo == NULL)
aio_init_aioinfo(p);
if ((nent + num_queue_count) > max_queue_count)
return EAGAIN;
ki = p->p_aioinfo;
if ((nent + ki->kaio_queue_count) > ki->kaio_qallowed_count)
return EAGAIN;
lj = zalloc(aiolio_zone);
if (!lj)
return EAGAIN;
lj->lioj_flags = 0;
lj->lioj_buffer_count = 0;
lj->lioj_buffer_finished_count = 0;
lj->lioj_queue_count = 0;
lj->lioj_queue_finished_count = 0;
lj->lioj_ki = ki;
/*
* Setup signal.
*/
if (uap->sig && (uap->mode == LIO_NOWAIT)) {
error = copyin(uap->sig, &lj->lioj_signal,
sizeof(lj->lioj_signal));
if (error) {
zfree(aiolio_zone, lj);
return error;
}
if (!_SIG_VALID(lj->lioj_signal.sigev_signo)) {
zfree(aiolio_zone, lj);
return EINVAL;
}
lj->lioj_flags |= LIOJ_SIGNAL;
lj->lioj_flags &= ~LIOJ_SIGNAL_POSTED;
} else
lj->lioj_flags &= ~LIOJ_SIGNAL;
TAILQ_INSERT_TAIL(&ki->kaio_liojoblist, lj, lioj_list);
/*
* Get pointers to the list of I/O requests.
*/
nerror = 0;
nentqueued = 0;
cbptr = uap->acb_list;
for (i = 0; i < uap->nent; i++) {
iocb = (struct aiocb *)(intptr_t)fuword((caddr_t)&cbptr[i]);
if (((intptr_t)iocb != -1) && ((intptr_t)iocb != NULL)) {
error = _aio_aqueue(td, iocb, lj, 0);
if (error == 0)
nentqueued++;
else
nerror++;
}
}
/*
* If we haven't queued any, then just return error.
*/
if (nentqueued == 0)
return 0;
/*
* Calculate the appropriate error return.
*/
runningcode = 0;
if (nerror)
runningcode = EIO;
if (uap->mode == LIO_WAIT) {
int command, found, jobref;
for (;;) {
found = 0;
for (i = 0; i < uap->nent; i++) {
/*
* Fetch address of the control buf pointer in
* user space.
*/
iocb = (struct aiocb *)(intptr_t)fuword((caddr_t)&cbptr[i]);
if (((intptr_t)iocb == -1) || ((intptr_t)iocb
== 0))
continue;
/*
* Fetch the associated command from user space.
*/
command = fuword(&iocb->aio_lio_opcode);
if (command == LIO_NOP) {
found++;
continue;
}
jobref = fuword(&iocb->_aiocb_private.kernelinfo);
TAILQ_FOREACH(cb, &ki->kaio_jobdone, plist) {
if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo)
== jobref) {
if (cb->uaiocb.aio_lio_opcode
== LIO_WRITE) {
p->p_stats->p_ru.ru_oublock
+=
cb->outputcharge;
cb->outputcharge = 0;
} else if (cb->uaiocb.aio_lio_opcode
== LIO_READ) {
p->p_stats->p_ru.ru_inblock
+= cb->inputcharge;
cb->inputcharge = 0;
}
found++;
break;
}
}
s = splbio();
TAILQ_FOREACH(cb, &ki->kaio_bufdone, plist) {
if (((intptr_t)cb->uaiocb._aiocb_private.kernelinfo)
== jobref) {
found++;
break;
}
}
splx(s);
}
/*
* If all I/Os have been disposed of, then we can
* return.
*/
if (found == nentqueued)
return runningcode;
ki->kaio_flags |= KAIO_WAKEUP;
error = tsleep(p, PRIBIO | PCATCH, "aiospn", 0);
if (error == EINTR)
return EINTR;
else if (error == EWOULDBLOCK)
return EAGAIN;
}
}
return runningcode;
}
/*
* This is a weird hack so that we can post a signal. It is safe to do so from
* a timeout routine, but *not* from an interrupt routine.
*/
static void
process_signal(void *aioj)
{
struct aiocblist *aiocbe = aioj;
struct aio_liojob *lj = aiocbe->lio;
struct aiocb *cb = &aiocbe->uaiocb;
if ((lj) && (lj->lioj_signal.sigev_notify == SIGEV_SIGNAL) &&
(lj->lioj_queue_count == lj->lioj_queue_finished_count)) {
PROC_LOCK(lj->lioj_ki->kaio_p);
psignal(lj->lioj_ki->kaio_p, lj->lioj_signal.sigev_signo);
PROC_UNLOCK(lj->lioj_ki->kaio_p);
lj->lioj_flags |= LIOJ_SIGNAL_POSTED;
}
if (cb->aio_sigevent.sigev_notify == SIGEV_SIGNAL) {
PROC_LOCK(aiocbe->userproc);
psignal(aiocbe->userproc, cb->aio_sigevent.sigev_signo);
PROC_UNLOCK(aiocbe->userproc);
}
}
/*
* Interrupt handler for physio, performs the necessary process wakeups, and
* signals.
*/
static void
aio_physwakeup(struct buf *bp)
{
struct aiocblist *aiocbe;
struct proc *p;
struct kaioinfo *ki;
struct aio_liojob *lj;
wakeup(bp);
aiocbe = (struct aiocblist *)bp->b_spc;
if (aiocbe) {
p = bp->b_caller1;
aiocbe->jobstate = JOBST_JOBBFINISHED;
aiocbe->uaiocb._aiocb_private.status -= bp->b_resid;
aiocbe->uaiocb._aiocb_private.error = 0;
aiocbe->jobflags |= AIOCBLIST_DONE;
if (bp->b_ioflags & BIO_ERROR)
aiocbe->uaiocb._aiocb_private.error = bp->b_error;
lj = aiocbe->lio;
if (lj) {
lj->lioj_buffer_finished_count++;
/*
* wakeup/signal if all of the interrupt jobs are done.
*/
if (lj->lioj_buffer_finished_count ==
lj->lioj_buffer_count) {
/*
* Post a signal if it is called for.
*/
if ((lj->lioj_flags &
(LIOJ_SIGNAL|LIOJ_SIGNAL_POSTED)) ==
LIOJ_SIGNAL) {
lj->lioj_flags |= LIOJ_SIGNAL_POSTED;
aiocbe->timeouthandle =
timeout(process_signal,
aiocbe, 0);
}
}
}
ki = p->p_aioinfo;
if (ki) {
ki->kaio_buffer_finished_count++;
TAILQ_REMOVE(&aio_bufjobs, aiocbe, list);
TAILQ_REMOVE(&ki->kaio_bufqueue, aiocbe, plist);
TAILQ_INSERT_TAIL(&ki->kaio_bufdone, aiocbe, plist);
KNOTE(&aiocbe->klist, 0);
/* Do the wakeup. */
if (ki->kaio_flags & (KAIO_RUNDOWN|KAIO_WAKEUP)) {
ki->kaio_flags &= ~KAIO_WAKEUP;
wakeup(p);
}
}
if (aiocbe->uaiocb.aio_sigevent.sigev_notify == SIGEV_SIGNAL)
aiocbe->timeouthandle =
timeout(process_signal, aiocbe, 0);
}
}
/* syscall - wait for the next completion of an aio request */
int
aio_waitcomplete(struct thread *td, struct aio_waitcomplete_args *uap)
{
struct proc *p = td->td_proc;
struct timeval atv;
struct timespec ts;
struct aiocb **cbptr;
struct kaioinfo *ki;
struct aiocblist *cb = NULL;
int error, s, timo;
suword(uap->aiocbp, (int)NULL);
timo = 0;
if (uap->timeout) {
/* Get timespec struct. */
error = copyin(uap->timeout, &ts, sizeof(ts));
if (error)
return error;
if ((ts.tv_nsec < 0) || (ts.tv_nsec >= 1000000000))
return (EINVAL);
TIMESPEC_TO_TIMEVAL(&atv, &ts);
if (itimerfix(&atv))
return (EINVAL);
timo = tvtohz(&atv);
}
ki = p->p_aioinfo;
if (ki == NULL)
return EAGAIN;
cbptr = uap->aiocbp;
for (;;) {
if ((cb = TAILQ_FIRST(&ki->kaio_jobdone)) != 0) {
suword(uap->aiocbp, (uintptr_t)cb->uuaiocb);
td->td_retval[0] = cb->uaiocb._aiocb_private.status;
if (cb->uaiocb.aio_lio_opcode == LIO_WRITE) {
p->p_stats->p_ru.ru_oublock +=
cb->outputcharge;
cb->outputcharge = 0;
} else if (cb->uaiocb.aio_lio_opcode == LIO_READ) {
p->p_stats->p_ru.ru_inblock += cb->inputcharge;
cb->inputcharge = 0;
}
aio_free_entry(cb);
return cb->uaiocb._aiocb_private.error;
}
s = splbio();
if ((cb = TAILQ_FIRST(&ki->kaio_bufdone)) != 0 ) {
splx(s);
suword(uap->aiocbp, (uintptr_t)cb->uuaiocb);
td->td_retval[0] = cb->uaiocb._aiocb_private.status;
aio_free_entry(cb);
return cb->uaiocb._aiocb_private.error;
}
ki->kaio_flags |= KAIO_WAKEUP;
error = tsleep(p, PRIBIO | PCATCH, "aiowc", timo);
splx(s);
if (error == ERESTART)
return EINTR;
else if (error < 0)
return error;
else if (error == EINTR)
return EINTR;
else if (error == EWOULDBLOCK)
return EAGAIN;
}
}
/* kqueue attach function */
static int
filt_aioattach(struct knote *kn)
{
struct aiocblist *aiocbe = (struct aiocblist *)kn->kn_id;
/*
* The aiocbe pointer must be validated before using it, so
* registration is restricted to the kernel; the user cannot
* set EV_FLAG1.
*/
if ((kn->kn_flags & EV_FLAG1) == 0)
return (EPERM);
kn->kn_flags &= ~EV_FLAG1;
SLIST_INSERT_HEAD(&aiocbe->klist, kn, kn_selnext);
return (0);
}
/* kqueue detach function */
static void
filt_aiodetach(struct knote *kn)
{
struct aiocblist *aiocbe = (struct aiocblist *)kn->kn_id;
SLIST_REMOVE(&aiocbe->klist, kn, knote, kn_selnext);
}
/* kqueue filter function */
/*ARGSUSED*/
static int
filt_aio(struct knote *kn, long hint)
{
struct aiocblist *aiocbe = (struct aiocblist *)kn->kn_id;
kn->kn_data = aiocbe->uaiocb._aiocb_private.error;
if (aiocbe->jobstate != JOBST_JOBFINISHED &&
aiocbe->jobstate != JOBST_JOBBFINISHED)
return (0);
kn->kn_flags |= EV_EOF;
return (1);
}
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