124e4c3be8
Use this in all the places where sleeping with the lock held is not an issue. The distinction will become significant once we finalize the exact lock-type to use for this kind of case.
1140 lines
24 KiB
C
1140 lines
24 KiB
C
/*
|
|
* Copyright (c) 1982, 1986, 1989, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
* (c) UNIX System Laboratories, Inc.
|
|
* All or some portions of this file are derived from material licensed
|
|
* to the University of California by American Telephone and Telegraph
|
|
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
|
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* the permission of UNIX System Laboratories, Inc.
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|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
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* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
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* SUCH DAMAGE.
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*
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|
* @(#)sys_generic.c 8.5 (Berkeley) 1/21/94
|
|
*/
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|
|
|
#include <sys/cdefs.h>
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|
__FBSDID("$FreeBSD$");
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|
|
|
#include "opt_ktrace.h"
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|
|
|
#include <sys/param.h>
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|
#include <sys/systm.h>
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|
#include <sys/sysproto.h>
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|
#include <sys/filedesc.h>
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|
#include <sys/filio.h>
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|
#include <sys/fcntl.h>
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|
#include <sys/file.h>
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|
#include <sys/proc.h>
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|
#include <sys/signalvar.h>
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|
#include <sys/socketvar.h>
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|
#include <sys/uio.h>
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|
#include <sys/kernel.h>
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|
#include <sys/limits.h>
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|
#include <sys/malloc.h>
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|
#include <sys/poll.h>
|
|
#include <sys/resourcevar.h>
|
|
#include <sys/selinfo.h>
|
|
#include <sys/sleepqueue.h>
|
|
#include <sys/syscallsubr.h>
|
|
#include <sys/sysctl.h>
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|
#include <sys/sysent.h>
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|
#include <sys/vnode.h>
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|
#include <sys/bio.h>
|
|
#include <sys/buf.h>
|
|
#include <sys/condvar.h>
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|
#ifdef KTRACE
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|
#include <sys/ktrace.h>
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|
#endif
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|
#include <vm/vm.h>
|
|
#include <vm/vm_page.h>
|
|
|
|
static MALLOC_DEFINE(M_IOCTLOPS, "ioctlops", "ioctl data buffer");
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|
static MALLOC_DEFINE(M_SELECT, "select", "select() buffer");
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|
MALLOC_DEFINE(M_IOV, "iov", "large iov's");
|
|
|
|
static int pollscan(struct thread *, struct pollfd *, u_int);
|
|
static int selscan(struct thread *, fd_mask **, fd_mask **, int);
|
|
static int dofileread(struct thread *, struct file *, int, void *,
|
|
size_t, off_t, int);
|
|
static int dofilewrite(struct thread *, struct file *, int,
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|
const void *, size_t, off_t, int);
|
|
static void doselwakeup(struct selinfo *, int);
|
|
|
|
/*
|
|
* Read system call.
|
|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
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|
struct read_args {
|
|
int fd;
|
|
void *buf;
|
|
size_t nbyte;
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|
};
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|
#endif
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|
/*
|
|
* MPSAFE
|
|
*/
|
|
int
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|
read(td, uap)
|
|
struct thread *td;
|
|
struct read_args *uap;
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|
{
|
|
struct file *fp;
|
|
int error;
|
|
|
|
if ((error = fget_read(td, uap->fd, &fp)) == 0) {
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|
error = dofileread(td, fp, uap->fd, uap->buf,
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uap->nbyte, (off_t)-1, 0);
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|
fdrop(fp, td);
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|
}
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|
return(error);
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|
}
|
|
|
|
/*
|
|
* Pread system call
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|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
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|
struct pread_args {
|
|
int fd;
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|
void *buf;
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|
size_t nbyte;
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|
int pad;
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|
off_t offset;
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|
};
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|
#endif
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
int
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|
pread(td, uap)
|
|
struct thread *td;
|
|
struct pread_args *uap;
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|
{
|
|
struct file *fp;
|
|
int error;
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|
|
|
if ((error = fget_read(td, uap->fd, &fp)) != 0)
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|
return (error);
|
|
if (!(fp->f_ops->fo_flags & DFLAG_SEEKABLE))
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|
error = ESPIPE;
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|
else if (uap->offset < 0 && fp->f_vnode->v_type != VCHR)
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|
error = EINVAL;
|
|
else {
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|
error = dofileread(td, fp, uap->fd, uap->buf, uap->nbyte,
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|
uap->offset, FOF_OFFSET);
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|
}
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|
fdrop(fp, td);
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|
return(error);
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|
}
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|
|
|
/*
|
|
* Code common for read and pread
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|
*/
|
|
static int
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|
dofileread(td, fp, fd, buf, nbyte, offset, flags)
|
|
struct thread *td;
|
|
struct file *fp;
|
|
int fd, flags;
|
|
void *buf;
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|
size_t nbyte;
|
|
off_t offset;
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|
{
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|
struct uio auio;
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|
struct iovec aiov;
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|
long cnt, error = 0;
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#ifdef KTRACE
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|
struct uio *ktruio = NULL;
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|
#endif
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|
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|
aiov.iov_base = buf;
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|
aiov.iov_len = nbyte;
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|
auio.uio_iov = &aiov;
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|
auio.uio_iovcnt = 1;
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|
auio.uio_offset = offset;
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|
if (nbyte > INT_MAX)
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|
return (EINVAL);
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|
auio.uio_resid = nbyte;
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|
auio.uio_rw = UIO_READ;
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|
auio.uio_segflg = UIO_USERSPACE;
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|
auio.uio_td = td;
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|
#ifdef KTRACE
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|
if (KTRPOINT(td, KTR_GENIO))
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|
ktruio = cloneuio(&auio);
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|
#endif
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|
cnt = nbyte;
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|
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|
if ((error = fo_read(fp, &auio, td->td_ucred, flags, td))) {
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|
if (auio.uio_resid != cnt && (error == ERESTART ||
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|
error == EINTR || error == EWOULDBLOCK))
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|
error = 0;
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|
}
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|
cnt -= auio.uio_resid;
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|
#ifdef KTRACE
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|
if (ktruio != NULL) {
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|
ktruio->uio_resid = cnt;
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|
ktrgenio(fd, UIO_READ, ktruio, error);
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|
}
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|
#endif
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|
td->td_retval[0] = cnt;
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|
return (error);
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|
}
|
|
|
|
/*
|
|
* Scatter read system call.
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|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
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|
struct readv_args {
|
|
int fd;
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|
struct iovec *iovp;
|
|
u_int iovcnt;
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|
};
|
|
#endif
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|
/*
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|
* MPSAFE
|
|
*/
|
|
int
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|
readv(struct thread *td, struct readv_args *uap)
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|
{
|
|
struct file *fp;
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|
struct uio *auio = NULL;
|
|
long cnt;
|
|
int error;
|
|
#ifdef KTRACE
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|
struct uio *ktruio = NULL;
|
|
#endif
|
|
|
|
error = fget_read(td, uap->fd, &fp);
|
|
if (error)
|
|
return (error);
|
|
error = copyinuio(uap->iovp, uap->iovcnt, &auio);
|
|
if (error) {
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|
fdrop(fp, td);
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|
return (error);
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|
}
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|
auio->uio_rw = UIO_READ;
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|
auio->uio_td = td;
|
|
#ifdef KTRACE
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|
if (KTRPOINT(td, KTR_GENIO))
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|
ktruio = cloneuio(auio);
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|
#endif
|
|
cnt = auio->uio_resid;
|
|
if ((error = fo_read(fp, auio, td->td_ucred, 0, td))) {
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|
if (auio->uio_resid != cnt && (error == ERESTART ||
|
|
error == EINTR || error == EWOULDBLOCK))
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|
error = 0;
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|
}
|
|
cnt -= auio->uio_resid;
|
|
#ifdef KTRACE
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|
if (ktruio != NULL) {
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|
ktruio->uio_resid = cnt;
|
|
ktrgenio(uap->fd, UIO_READ, ktruio, error);
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|
}
|
|
#endif
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|
td->td_retval[0] = cnt;
|
|
free(auio, M_IOV);
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|
fdrop(fp, td);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Write system call
|
|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
|
|
struct write_args {
|
|
int fd;
|
|
const void *buf;
|
|
size_t nbyte;
|
|
};
|
|
#endif
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
int
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|
write(td, uap)
|
|
struct thread *td;
|
|
struct write_args *uap;
|
|
{
|
|
struct file *fp;
|
|
int error;
|
|
|
|
if ((error = fget_write(td, uap->fd, &fp)) == 0) {
|
|
error = dofilewrite(td, fp, uap->fd, uap->buf, uap->nbyte,
|
|
(off_t)-1, 0);
|
|
fdrop(fp, td);
|
|
} else {
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|
error = EBADF; /* XXX this can't be right */
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|
}
|
|
return(error);
|
|
}
|
|
|
|
/*
|
|
* Pwrite system call
|
|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
|
|
struct pwrite_args {
|
|
int fd;
|
|
const void *buf;
|
|
size_t nbyte;
|
|
int pad;
|
|
off_t offset;
|
|
};
|
|
#endif
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
pwrite(td, uap)
|
|
struct thread *td;
|
|
struct pwrite_args *uap;
|
|
{
|
|
struct file *fp;
|
|
int error;
|
|
|
|
if ((error = fget_write(td, uap->fd, &fp)) == 0) {
|
|
if (!(fp->f_ops->fo_flags & DFLAG_SEEKABLE))
|
|
error = ESPIPE;
|
|
else if (uap->offset < 0 && fp->f_vnode->v_type != VCHR)
|
|
error = EINVAL;
|
|
else {
|
|
error = dofilewrite(td, fp, uap->fd, uap->buf,
|
|
uap->nbyte, uap->offset, FOF_OFFSET);
|
|
}
|
|
fdrop(fp, td);
|
|
} else {
|
|
error = EBADF; /* this can't be right */
|
|
}
|
|
return(error);
|
|
}
|
|
|
|
static int
|
|
dofilewrite(td, fp, fd, buf, nbyte, offset, flags)
|
|
struct thread *td;
|
|
struct file *fp;
|
|
int fd, flags;
|
|
const void *buf;
|
|
size_t nbyte;
|
|
off_t offset;
|
|
{
|
|
struct uio auio;
|
|
struct iovec aiov;
|
|
long cnt, error = 0;
|
|
#ifdef KTRACE
|
|
struct uio *ktruio = NULL;
|
|
#endif
|
|
|
|
aiov.iov_base = (void *)(uintptr_t)buf;
|
|
aiov.iov_len = nbyte;
|
|
auio.uio_iov = &aiov;
|
|
auio.uio_iovcnt = 1;
|
|
auio.uio_offset = offset;
|
|
if (nbyte > INT_MAX)
|
|
return (EINVAL);
|
|
auio.uio_resid = nbyte;
|
|
auio.uio_rw = UIO_WRITE;
|
|
auio.uio_segflg = UIO_USERSPACE;
|
|
auio.uio_td = td;
|
|
#ifdef KTRACE
|
|
if (KTRPOINT(td, KTR_GENIO))
|
|
ktruio = cloneuio(&auio);
|
|
#endif
|
|
cnt = nbyte;
|
|
if (fp->f_type == DTYPE_VNODE)
|
|
bwillwrite();
|
|
if ((error = fo_write(fp, &auio, td->td_ucred, flags, td))) {
|
|
if (auio.uio_resid != cnt && (error == ERESTART ||
|
|
error == EINTR || error == EWOULDBLOCK))
|
|
error = 0;
|
|
/* Socket layer is responsible for issuing SIGPIPE. */
|
|
if (error == EPIPE && fp->f_type != DTYPE_SOCKET) {
|
|
PROC_LOCK(td->td_proc);
|
|
psignal(td->td_proc, SIGPIPE);
|
|
PROC_UNLOCK(td->td_proc);
|
|
}
|
|
}
|
|
cnt -= auio.uio_resid;
|
|
#ifdef KTRACE
|
|
if (ktruio != NULL) {
|
|
ktruio->uio_resid = cnt;
|
|
ktrgenio(fd, UIO_WRITE, ktruio, error);
|
|
}
|
|
#endif
|
|
td->td_retval[0] = cnt;
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Gather write system call
|
|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
|
|
struct writev_args {
|
|
int fd;
|
|
struct iovec *iovp;
|
|
u_int iovcnt;
|
|
};
|
|
#endif
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
writev(struct thread *td, struct writev_args *uap)
|
|
{
|
|
struct file *fp;
|
|
struct uio *auio = NULL;
|
|
long cnt;
|
|
int error;
|
|
#ifdef KTRACE
|
|
struct uio *ktruio = NULL;
|
|
#endif
|
|
|
|
error = fget_write(td, uap->fd, &fp);
|
|
if (error)
|
|
return (EBADF);
|
|
error = copyinuio(uap->iovp, uap->iovcnt, &auio);
|
|
if (error) {
|
|
fdrop(fp, td);
|
|
return (error);
|
|
}
|
|
auio->uio_rw = UIO_WRITE;
|
|
auio->uio_td = td;
|
|
#ifdef KTRACE
|
|
if (KTRPOINT(td, KTR_GENIO))
|
|
ktruio = cloneuio(auio);
|
|
#endif
|
|
cnt = auio->uio_resid;
|
|
if (fp->f_type == DTYPE_VNODE)
|
|
bwillwrite();
|
|
if ((error = fo_write(fp, auio, td->td_ucred, 0, td))) {
|
|
if (auio->uio_resid != cnt && (error == ERESTART ||
|
|
error == EINTR || error == EWOULDBLOCK))
|
|
error = 0;
|
|
if (error == EPIPE) {
|
|
PROC_LOCK(td->td_proc);
|
|
psignal(td->td_proc, SIGPIPE);
|
|
PROC_UNLOCK(td->td_proc);
|
|
}
|
|
}
|
|
cnt -= auio->uio_resid;
|
|
#ifdef KTRACE
|
|
if (ktruio != NULL) {
|
|
ktruio->uio_resid = cnt;
|
|
ktrgenio(uap->fd, UIO_WRITE, ktruio, error);
|
|
}
|
|
#endif
|
|
td->td_retval[0] = cnt;
|
|
fdrop(fp, td);
|
|
free(auio, M_IOV);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Ioctl system call
|
|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
|
|
struct ioctl_args {
|
|
int fd;
|
|
u_long com;
|
|
caddr_t data;
|
|
};
|
|
#endif
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
ioctl(td, uap)
|
|
struct thread *td;
|
|
register struct ioctl_args *uap;
|
|
{
|
|
struct file *fp;
|
|
register struct filedesc *fdp;
|
|
register u_long com;
|
|
int error = 0;
|
|
register u_int size;
|
|
caddr_t data, memp;
|
|
int tmp;
|
|
#define STK_PARAMS 128
|
|
union {
|
|
char stkbuf[STK_PARAMS];
|
|
long align;
|
|
} ubuf;
|
|
|
|
if ((error = fget(td, uap->fd, &fp)) != 0)
|
|
return (error);
|
|
mtx_lock(&Giant);
|
|
if ((fp->f_flag & (FREAD | FWRITE)) == 0) {
|
|
fdrop(fp, td);
|
|
mtx_unlock(&Giant);
|
|
return (EBADF);
|
|
}
|
|
fdp = td->td_proc->p_fd;
|
|
switch (com = uap->com) {
|
|
case FIONCLEX:
|
|
FILEDESC_LOCK_FAST(fdp);
|
|
fdp->fd_ofileflags[uap->fd] &= ~UF_EXCLOSE;
|
|
FILEDESC_UNLOCK_FAST(fdp);
|
|
fdrop(fp, td);
|
|
mtx_unlock(&Giant);
|
|
return (0);
|
|
case FIOCLEX:
|
|
FILEDESC_LOCK_FAST(fdp);
|
|
fdp->fd_ofileflags[uap->fd] |= UF_EXCLOSE;
|
|
FILEDESC_UNLOCK_FAST(fdp);
|
|
fdrop(fp, td);
|
|
mtx_unlock(&Giant);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Interpret high order word to find amount of data to be
|
|
* copied to/from the user's address space.
|
|
*/
|
|
size = IOCPARM_LEN(com);
|
|
if (size > IOCPARM_MAX) {
|
|
fdrop(fp, td);
|
|
mtx_unlock(&Giant);
|
|
return (ENOTTY);
|
|
}
|
|
|
|
memp = NULL;
|
|
if (size > sizeof (ubuf.stkbuf)) {
|
|
memp = malloc((u_long)size, M_IOCTLOPS, M_WAITOK);
|
|
data = memp;
|
|
} else {
|
|
data = ubuf.stkbuf;
|
|
}
|
|
if (com&IOC_IN) {
|
|
if (size) {
|
|
error = copyin(uap->data, data, (u_int)size);
|
|
if (error) {
|
|
if (memp)
|
|
free(memp, M_IOCTLOPS);
|
|
fdrop(fp, td);
|
|
goto done;
|
|
}
|
|
} else {
|
|
*(caddr_t *)data = uap->data;
|
|
}
|
|
} else if ((com&IOC_OUT) && size) {
|
|
/*
|
|
* Zero the buffer so the user always
|
|
* gets back something deterministic.
|
|
*/
|
|
bzero(data, size);
|
|
} else if (com&IOC_VOID) {
|
|
*(caddr_t *)data = uap->data;
|
|
}
|
|
|
|
switch (com) {
|
|
|
|
case FIONBIO:
|
|
FILE_LOCK(fp);
|
|
if ((tmp = *(int *)data))
|
|
fp->f_flag |= FNONBLOCK;
|
|
else
|
|
fp->f_flag &= ~FNONBLOCK;
|
|
FILE_UNLOCK(fp);
|
|
error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td);
|
|
break;
|
|
|
|
case FIOASYNC:
|
|
FILE_LOCK(fp);
|
|
if ((tmp = *(int *)data))
|
|
fp->f_flag |= FASYNC;
|
|
else
|
|
fp->f_flag &= ~FASYNC;
|
|
FILE_UNLOCK(fp);
|
|
error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td);
|
|
break;
|
|
|
|
default:
|
|
error = fo_ioctl(fp, com, data, td->td_ucred, td);
|
|
/*
|
|
* Copy any data to user, size was
|
|
* already set and checked above.
|
|
*/
|
|
if (error == 0 && (com&IOC_OUT) && size)
|
|
error = copyout(data, uap->data, (u_int)size);
|
|
break;
|
|
}
|
|
if (memp)
|
|
free(memp, M_IOCTLOPS);
|
|
fdrop(fp, td);
|
|
done:
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* sellock and selwait are initialized in selectinit() via SYSINIT.
|
|
*/
|
|
struct mtx sellock;
|
|
struct cv selwait;
|
|
u_int nselcoll; /* Select collisions since boot */
|
|
SYSCTL_UINT(_kern, OID_AUTO, nselcoll, CTLFLAG_RD, &nselcoll, 0, "");
|
|
|
|
/*
|
|
* Select system call.
|
|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
|
|
struct select_args {
|
|
int nd;
|
|
fd_set *in, *ou, *ex;
|
|
struct timeval *tv;
|
|
};
|
|
#endif
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
select(td, uap)
|
|
register struct thread *td;
|
|
register struct select_args *uap;
|
|
{
|
|
struct timeval tv, *tvp;
|
|
int error;
|
|
|
|
if (uap->tv != NULL) {
|
|
error = copyin(uap->tv, &tv, sizeof(tv));
|
|
if (error)
|
|
return (error);
|
|
tvp = &tv;
|
|
} else
|
|
tvp = NULL;
|
|
|
|
return (kern_select(td, uap->nd, uap->in, uap->ou, uap->ex, tvp));
|
|
}
|
|
|
|
int
|
|
kern_select(struct thread *td, int nd, fd_set *fd_in, fd_set *fd_ou,
|
|
fd_set *fd_ex, struct timeval *tvp)
|
|
{
|
|
struct filedesc *fdp;
|
|
/*
|
|
* The magic 2048 here is chosen to be just enough for FD_SETSIZE
|
|
* infds with the new FD_SETSIZE of 1024, and more than enough for
|
|
* FD_SETSIZE infds, outfds and exceptfds with the old FD_SETSIZE
|
|
* of 256.
|
|
*/
|
|
fd_mask s_selbits[howmany(2048, NFDBITS)];
|
|
fd_mask *ibits[3], *obits[3], *selbits, *sbp;
|
|
struct timeval atv, rtv, ttv;
|
|
int error, timo;
|
|
u_int ncoll, nbufbytes, ncpbytes, nfdbits;
|
|
|
|
if (nd < 0)
|
|
return (EINVAL);
|
|
fdp = td->td_proc->p_fd;
|
|
/*
|
|
* XXX: kern_select() currently requires that we acquire Giant
|
|
* even if none of the file descriptors we poll requires Giant.
|
|
*/
|
|
mtx_lock(&Giant);
|
|
FILEDESC_LOCK_FAST(fdp);
|
|
|
|
if (nd > td->td_proc->p_fd->fd_nfiles)
|
|
nd = td->td_proc->p_fd->fd_nfiles; /* forgiving; slightly wrong */
|
|
FILEDESC_UNLOCK_FAST(fdp);
|
|
|
|
/*
|
|
* Allocate just enough bits for the non-null fd_sets. Use the
|
|
* preallocated auto buffer if possible.
|
|
*/
|
|
nfdbits = roundup(nd, NFDBITS);
|
|
ncpbytes = nfdbits / NBBY;
|
|
nbufbytes = 0;
|
|
if (fd_in != NULL)
|
|
nbufbytes += 2 * ncpbytes;
|
|
if (fd_ou != NULL)
|
|
nbufbytes += 2 * ncpbytes;
|
|
if (fd_ex != NULL)
|
|
nbufbytes += 2 * ncpbytes;
|
|
if (nbufbytes <= sizeof s_selbits)
|
|
selbits = &s_selbits[0];
|
|
else
|
|
selbits = malloc(nbufbytes, M_SELECT, M_WAITOK);
|
|
|
|
/*
|
|
* Assign pointers into the bit buffers and fetch the input bits.
|
|
* Put the output buffers together so that they can be bzeroed
|
|
* together.
|
|
*/
|
|
sbp = selbits;
|
|
#define getbits(name, x) \
|
|
do { \
|
|
if (name == NULL) \
|
|
ibits[x] = NULL; \
|
|
else { \
|
|
ibits[x] = sbp + nbufbytes / 2 / sizeof *sbp; \
|
|
obits[x] = sbp; \
|
|
sbp += ncpbytes / sizeof *sbp; \
|
|
error = copyin(name, ibits[x], ncpbytes); \
|
|
if (error != 0) \
|
|
goto done_nosellock; \
|
|
} \
|
|
} while (0)
|
|
getbits(fd_in, 0);
|
|
getbits(fd_ou, 1);
|
|
getbits(fd_ex, 2);
|
|
#undef getbits
|
|
if (nbufbytes != 0)
|
|
bzero(selbits, nbufbytes / 2);
|
|
|
|
if (tvp != NULL) {
|
|
atv = *tvp;
|
|
if (itimerfix(&atv)) {
|
|
error = EINVAL;
|
|
goto done_nosellock;
|
|
}
|
|
getmicrouptime(&rtv);
|
|
timevaladd(&atv, &rtv);
|
|
} else {
|
|
atv.tv_sec = 0;
|
|
atv.tv_usec = 0;
|
|
}
|
|
timo = 0;
|
|
TAILQ_INIT(&td->td_selq);
|
|
mtx_lock(&sellock);
|
|
retry:
|
|
ncoll = nselcoll;
|
|
mtx_lock_spin(&sched_lock);
|
|
td->td_flags |= TDF_SELECT;
|
|
mtx_unlock_spin(&sched_lock);
|
|
mtx_unlock(&sellock);
|
|
|
|
error = selscan(td, ibits, obits, nd);
|
|
mtx_lock(&sellock);
|
|
if (error || td->td_retval[0])
|
|
goto done;
|
|
if (atv.tv_sec || atv.tv_usec) {
|
|
getmicrouptime(&rtv);
|
|
if (timevalcmp(&rtv, &atv, >=))
|
|
goto done;
|
|
ttv = atv;
|
|
timevalsub(&ttv, &rtv);
|
|
timo = ttv.tv_sec > 24 * 60 * 60 ?
|
|
24 * 60 * 60 * hz : tvtohz(&ttv);
|
|
}
|
|
|
|
/*
|
|
* An event of interest may occur while we do not hold
|
|
* sellock, so check TDF_SELECT and the number of
|
|
* collisions and rescan the file descriptors if
|
|
* necessary.
|
|
*/
|
|
mtx_lock_spin(&sched_lock);
|
|
if ((td->td_flags & TDF_SELECT) == 0 || nselcoll != ncoll) {
|
|
mtx_unlock_spin(&sched_lock);
|
|
goto retry;
|
|
}
|
|
mtx_unlock_spin(&sched_lock);
|
|
|
|
if (timo > 0)
|
|
error = cv_timedwait_sig(&selwait, &sellock, timo);
|
|
else
|
|
error = cv_wait_sig(&selwait, &sellock);
|
|
|
|
if (error == 0)
|
|
goto retry;
|
|
|
|
done:
|
|
clear_selinfo_list(td);
|
|
mtx_lock_spin(&sched_lock);
|
|
td->td_flags &= ~TDF_SELECT;
|
|
mtx_unlock_spin(&sched_lock);
|
|
mtx_unlock(&sellock);
|
|
|
|
done_nosellock:
|
|
/* select is not restarted after signals... */
|
|
if (error == ERESTART)
|
|
error = EINTR;
|
|
if (error == EWOULDBLOCK)
|
|
error = 0;
|
|
#define putbits(name, x) \
|
|
if (name && (error2 = copyout(obits[x], name, ncpbytes))) \
|
|
error = error2;
|
|
if (error == 0) {
|
|
int error2;
|
|
|
|
putbits(fd_in, 0);
|
|
putbits(fd_ou, 1);
|
|
putbits(fd_ex, 2);
|
|
#undef putbits
|
|
}
|
|
if (selbits != &s_selbits[0])
|
|
free(selbits, M_SELECT);
|
|
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
selscan(td, ibits, obits, nfd)
|
|
struct thread *td;
|
|
fd_mask **ibits, **obits;
|
|
int nfd;
|
|
{
|
|
int msk, i, fd;
|
|
fd_mask bits;
|
|
struct file *fp;
|
|
int n = 0;
|
|
/* Note: backend also returns POLLHUP/POLLERR if appropriate. */
|
|
static int flag[3] = { POLLRDNORM, POLLWRNORM, POLLRDBAND };
|
|
struct filedesc *fdp = td->td_proc->p_fd;
|
|
|
|
FILEDESC_LOCK(fdp);
|
|
for (msk = 0; msk < 3; msk++) {
|
|
if (ibits[msk] == NULL)
|
|
continue;
|
|
for (i = 0; i < nfd; i += NFDBITS) {
|
|
bits = ibits[msk][i/NFDBITS];
|
|
/* ffs(int mask) not portable, fd_mask is long */
|
|
for (fd = i; bits && fd < nfd; fd++, bits >>= 1) {
|
|
if (!(bits & 1))
|
|
continue;
|
|
if ((fp = fget_locked(fdp, fd)) == NULL) {
|
|
FILEDESC_UNLOCK(fdp);
|
|
return (EBADF);
|
|
}
|
|
if (fo_poll(fp, flag[msk], td->td_ucred,
|
|
td)) {
|
|
obits[msk][(fd)/NFDBITS] |=
|
|
((fd_mask)1 << ((fd) % NFDBITS));
|
|
n++;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
FILEDESC_UNLOCK(fdp);
|
|
td->td_retval[0] = n;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Poll system call.
|
|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
|
|
struct poll_args {
|
|
struct pollfd *fds;
|
|
u_int nfds;
|
|
int timeout;
|
|
};
|
|
#endif
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
poll(td, uap)
|
|
struct thread *td;
|
|
struct poll_args *uap;
|
|
{
|
|
struct pollfd *bits;
|
|
struct pollfd smallbits[32];
|
|
struct timeval atv, rtv, ttv;
|
|
int error = 0, timo;
|
|
u_int ncoll, nfds;
|
|
size_t ni;
|
|
|
|
nfds = uap->nfds;
|
|
|
|
/*
|
|
* XXX: poll() currently requires that we acquire Giant even if
|
|
* none of the file descriptors we poll requires Giant.
|
|
*/
|
|
mtx_lock(&Giant);
|
|
/*
|
|
* This is kinda bogus. We have fd limits, but that is not
|
|
* really related to the size of the pollfd array. Make sure
|
|
* we let the process use at least FD_SETSIZE entries and at
|
|
* least enough for the current limits. We want to be reasonably
|
|
* safe, but not overly restrictive.
|
|
*/
|
|
PROC_LOCK(td->td_proc);
|
|
if ((nfds > lim_cur(td->td_proc, RLIMIT_NOFILE)) &&
|
|
(nfds > FD_SETSIZE)) {
|
|
PROC_UNLOCK(td->td_proc);
|
|
error = EINVAL;
|
|
goto done2;
|
|
}
|
|
PROC_UNLOCK(td->td_proc);
|
|
ni = nfds * sizeof(struct pollfd);
|
|
if (ni > sizeof(smallbits))
|
|
bits = malloc(ni, M_TEMP, M_WAITOK);
|
|
else
|
|
bits = smallbits;
|
|
error = copyin(uap->fds, bits, ni);
|
|
if (error)
|
|
goto done_nosellock;
|
|
if (uap->timeout != INFTIM) {
|
|
atv.tv_sec = uap->timeout / 1000;
|
|
atv.tv_usec = (uap->timeout % 1000) * 1000;
|
|
if (itimerfix(&atv)) {
|
|
error = EINVAL;
|
|
goto done_nosellock;
|
|
}
|
|
getmicrouptime(&rtv);
|
|
timevaladd(&atv, &rtv);
|
|
} else {
|
|
atv.tv_sec = 0;
|
|
atv.tv_usec = 0;
|
|
}
|
|
timo = 0;
|
|
TAILQ_INIT(&td->td_selq);
|
|
mtx_lock(&sellock);
|
|
retry:
|
|
ncoll = nselcoll;
|
|
mtx_lock_spin(&sched_lock);
|
|
td->td_flags |= TDF_SELECT;
|
|
mtx_unlock_spin(&sched_lock);
|
|
mtx_unlock(&sellock);
|
|
|
|
error = pollscan(td, bits, nfds);
|
|
mtx_lock(&sellock);
|
|
if (error || td->td_retval[0])
|
|
goto done;
|
|
if (atv.tv_sec || atv.tv_usec) {
|
|
getmicrouptime(&rtv);
|
|
if (timevalcmp(&rtv, &atv, >=))
|
|
goto done;
|
|
ttv = atv;
|
|
timevalsub(&ttv, &rtv);
|
|
timo = ttv.tv_sec > 24 * 60 * 60 ?
|
|
24 * 60 * 60 * hz : tvtohz(&ttv);
|
|
}
|
|
/*
|
|
* An event of interest may occur while we do not hold
|
|
* sellock, so check TDF_SELECT and the number of collisions
|
|
* and rescan the file descriptors if necessary.
|
|
*/
|
|
mtx_lock_spin(&sched_lock);
|
|
if ((td->td_flags & TDF_SELECT) == 0 || nselcoll != ncoll) {
|
|
mtx_unlock_spin(&sched_lock);
|
|
goto retry;
|
|
}
|
|
mtx_unlock_spin(&sched_lock);
|
|
|
|
if (timo > 0)
|
|
error = cv_timedwait_sig(&selwait, &sellock, timo);
|
|
else
|
|
error = cv_wait_sig(&selwait, &sellock);
|
|
|
|
if (error == 0)
|
|
goto retry;
|
|
|
|
done:
|
|
clear_selinfo_list(td);
|
|
mtx_lock_spin(&sched_lock);
|
|
td->td_flags &= ~TDF_SELECT;
|
|
mtx_unlock_spin(&sched_lock);
|
|
mtx_unlock(&sellock);
|
|
|
|
done_nosellock:
|
|
/* poll is not restarted after signals... */
|
|
if (error == ERESTART)
|
|
error = EINTR;
|
|
if (error == EWOULDBLOCK)
|
|
error = 0;
|
|
if (error == 0) {
|
|
error = copyout(bits, uap->fds, ni);
|
|
if (error)
|
|
goto out;
|
|
}
|
|
out:
|
|
if (ni > sizeof(smallbits))
|
|
free(bits, M_TEMP);
|
|
done2:
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
pollscan(td, fds, nfd)
|
|
struct thread *td;
|
|
struct pollfd *fds;
|
|
u_int nfd;
|
|
{
|
|
register struct filedesc *fdp = td->td_proc->p_fd;
|
|
int i;
|
|
struct file *fp;
|
|
int n = 0;
|
|
|
|
FILEDESC_LOCK(fdp);
|
|
for (i = 0; i < nfd; i++, fds++) {
|
|
if (fds->fd >= fdp->fd_nfiles) {
|
|
fds->revents = POLLNVAL;
|
|
n++;
|
|
} else if (fds->fd < 0) {
|
|
fds->revents = 0;
|
|
} else {
|
|
fp = fdp->fd_ofiles[fds->fd];
|
|
if (fp == NULL) {
|
|
fds->revents = POLLNVAL;
|
|
n++;
|
|
} else {
|
|
/*
|
|
* Note: backend also returns POLLHUP and
|
|
* POLLERR if appropriate.
|
|
*/
|
|
fds->revents = fo_poll(fp, fds->events,
|
|
td->td_ucred, td);
|
|
if (fds->revents != 0)
|
|
n++;
|
|
}
|
|
}
|
|
}
|
|
FILEDESC_UNLOCK(fdp);
|
|
td->td_retval[0] = n;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* OpenBSD poll system call.
|
|
* XXX this isn't quite a true representation.. OpenBSD uses select ops.
|
|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
|
|
struct openbsd_poll_args {
|
|
struct pollfd *fds;
|
|
u_int nfds;
|
|
int timeout;
|
|
};
|
|
#endif
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
openbsd_poll(td, uap)
|
|
register struct thread *td;
|
|
register struct openbsd_poll_args *uap;
|
|
{
|
|
return (poll(td, (struct poll_args *)uap));
|
|
}
|
|
|
|
/*
|
|
* Remove the references to the thread from all of the objects
|
|
* we were polling.
|
|
*
|
|
* This code assumes that the underlying owner of the selinfo
|
|
* structure will hold sellock before it changes it, and that
|
|
* it will unlink itself from our list if it goes away.
|
|
*/
|
|
void
|
|
clear_selinfo_list(td)
|
|
struct thread *td;
|
|
{
|
|
struct selinfo *si;
|
|
|
|
mtx_assert(&sellock, MA_OWNED);
|
|
TAILQ_FOREACH(si, &td->td_selq, si_thrlist)
|
|
si->si_thread = NULL;
|
|
TAILQ_INIT(&td->td_selq);
|
|
}
|
|
|
|
/*
|
|
* Record a select request.
|
|
*/
|
|
void
|
|
selrecord(selector, sip)
|
|
struct thread *selector;
|
|
struct selinfo *sip;
|
|
{
|
|
|
|
mtx_lock(&sellock);
|
|
/*
|
|
* If the selinfo's thread pointer is NULL then take ownership of it.
|
|
*
|
|
* If the thread pointer is not NULL and it points to another
|
|
* thread, then we have a collision.
|
|
*
|
|
* If the thread pointer is not NULL and points back to us then leave
|
|
* it alone as we've already added pointed it at us and added it to
|
|
* our list.
|
|
*/
|
|
if (sip->si_thread == NULL) {
|
|
sip->si_thread = selector;
|
|
TAILQ_INSERT_TAIL(&selector->td_selq, sip, si_thrlist);
|
|
} else if (sip->si_thread != selector) {
|
|
sip->si_flags |= SI_COLL;
|
|
}
|
|
|
|
mtx_unlock(&sellock);
|
|
}
|
|
|
|
/* Wake up a selecting thread. */
|
|
void
|
|
selwakeup(sip)
|
|
struct selinfo *sip;
|
|
{
|
|
doselwakeup(sip, -1);
|
|
}
|
|
|
|
/* Wake up a selecting thread, and set its priority. */
|
|
void
|
|
selwakeuppri(sip, pri)
|
|
struct selinfo *sip;
|
|
int pri;
|
|
{
|
|
doselwakeup(sip, pri);
|
|
}
|
|
|
|
/*
|
|
* Do a wakeup when a selectable event occurs.
|
|
*/
|
|
static void
|
|
doselwakeup(sip, pri)
|
|
struct selinfo *sip;
|
|
int pri;
|
|
{
|
|
struct thread *td;
|
|
|
|
mtx_lock(&sellock);
|
|
td = sip->si_thread;
|
|
if ((sip->si_flags & SI_COLL) != 0) {
|
|
nselcoll++;
|
|
sip->si_flags &= ~SI_COLL;
|
|
cv_broadcastpri(&selwait, pri);
|
|
}
|
|
if (td == NULL) {
|
|
mtx_unlock(&sellock);
|
|
return;
|
|
}
|
|
TAILQ_REMOVE(&td->td_selq, sip, si_thrlist);
|
|
sip->si_thread = NULL;
|
|
mtx_lock_spin(&sched_lock);
|
|
td->td_flags &= ~TDF_SELECT;
|
|
mtx_unlock_spin(&sched_lock);
|
|
sleepq_remove(td, &selwait);
|
|
mtx_unlock(&sellock);
|
|
}
|
|
|
|
static void selectinit(void *);
|
|
SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, selectinit, NULL)
|
|
|
|
/* ARGSUSED*/
|
|
static void
|
|
selectinit(dummy)
|
|
void *dummy;
|
|
{
|
|
cv_init(&selwait, "select");
|
|
mtx_init(&sellock, "sellck", NULL, MTX_DEF);
|
|
}
|