0c14ff0eb5
system calls now enter without Giant held, and then in some cases, acquire Giant explicitly. Remove a number of other MPSAFE annotations in the credential code and tweak one or two other adjacent comments.
1148 lines
24 KiB
C
1148 lines
24 KiB
C
/*-
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* Copyright (c) 1982, 1986, 1989, 1993
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* The Regents of the University of California. All rights reserved.
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* (c) UNIX System Laboratories, Inc.
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* All or some portions of this file are derived from material licensed
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* to the University of California by American Telephone and Telegraph
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* 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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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* 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
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* 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
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* 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
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* 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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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include "opt_compat.h"
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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>
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#include <sys/resourcevar.h>
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#include <sys/selinfo.h>
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#include <sys/sleepqueue.h>
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#include <sys/syscallsubr.h>
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#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>
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#include <sys/buf.h>
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#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>
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#include <vm/vm_page.h>
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|
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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");
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static int pollscan(struct thread *, struct pollfd *, u_int);
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static int selscan(struct thread *, fd_mask **, fd_mask **, int);
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static int dofileread(struct thread *, int, struct file *, struct uio *,
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off_t, int);
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static int dofilewrite(struct thread *, int, struct file *, struct uio *,
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off_t, int);
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static void doselwakeup(struct selinfo *, int);
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/*
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* Read system call.
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*/
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#ifndef _SYS_SYSPROTO_H_
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struct read_args {
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int fd;
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void *buf;
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size_t nbyte;
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};
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#endif
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int
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read(td, uap)
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struct thread *td;
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struct read_args *uap;
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{
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struct uio auio;
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struct iovec aiov;
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int error;
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if (uap->nbyte > INT_MAX)
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return (EINVAL);
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aiov.iov_base = uap->buf;
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aiov.iov_len = uap->nbyte;
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auio.uio_iov = &aiov;
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auio.uio_iovcnt = 1;
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auio.uio_resid = uap->nbyte;
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auio.uio_segflg = UIO_USERSPACE;
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error = kern_readv(td, uap->fd, &auio);
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return(error);
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}
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/*
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* Positioned read system call
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*/
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#ifndef _SYS_SYSPROTO_H_
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struct pread_args {
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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
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int
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pread(td, uap)
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struct thread *td;
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struct pread_args *uap;
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{
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struct uio auio;
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struct iovec aiov;
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int error;
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if (uap->nbyte > INT_MAX)
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return (EINVAL);
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aiov.iov_base = uap->buf;
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aiov.iov_len = uap->nbyte;
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auio.uio_iov = &aiov;
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auio.uio_iovcnt = 1;
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auio.uio_resid = uap->nbyte;
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auio.uio_segflg = UIO_USERSPACE;
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error = kern_preadv(td, uap->fd, &auio, uap->offset);
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return(error);
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}
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/*
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* Scatter read system call.
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*/
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#ifndef _SYS_SYSPROTO_H_
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struct readv_args {
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int fd;
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struct iovec *iovp;
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u_int iovcnt;
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};
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#endif
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int
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readv(struct thread *td, struct readv_args *uap)
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{
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struct uio *auio;
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int error;
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error = copyinuio(uap->iovp, uap->iovcnt, &auio);
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if (error)
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return (error);
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error = kern_readv(td, uap->fd, auio);
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free(auio, M_IOV);
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return (error);
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}
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int
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kern_readv(struct thread *td, int fd, struct uio *auio)
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{
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struct file *fp;
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int error;
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error = fget_read(td, fd, &fp);
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if (error)
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return (error);
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error = dofileread(td, fd, fp, auio, (off_t)-1, 0);
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fdrop(fp, td);
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return (error);
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}
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/*
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* Scatter positioned read system call.
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*/
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#ifndef _SYS_SYSPROTO_H_
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struct preadv_args {
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int fd;
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struct iovec *iovp;
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u_int iovcnt;
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off_t offset;
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};
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#endif
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int
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preadv(struct thread *td, struct preadv_args *uap)
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{
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struct uio *auio;
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int error;
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error = copyinuio(uap->iovp, uap->iovcnt, &auio);
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if (error)
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return (error);
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error = kern_preadv(td, uap->fd, auio, uap->offset);
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free(auio, M_IOV);
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return (error);
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}
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int
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kern_preadv(td, fd, auio, offset)
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struct thread *td;
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int fd;
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struct uio *auio;
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off_t offset;
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{
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struct file *fp;
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int error;
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error = fget_read(td, fd, &fp);
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if (error)
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return (error);
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if (!(fp->f_ops->fo_flags & DFLAG_SEEKABLE))
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error = ESPIPE;
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else if (offset < 0 && fp->f_vnode->v_type != VCHR)
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error = EINVAL;
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else
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error = dofileread(td, fd, fp, auio, offset, FOF_OFFSET);
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fdrop(fp, td);
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return (error);
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}
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/*
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* Common code for readv and preadv that reads data in
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* from a file using the passed in uio, offset, and flags.
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*/
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static int
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dofileread(td, fd, fp, auio, offset, flags)
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struct thread *td;
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int fd;
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struct file *fp;
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struct uio *auio;
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off_t offset;
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int flags;
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{
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ssize_t cnt;
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int error;
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#ifdef KTRACE
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struct uio *ktruio = NULL;
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#endif
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/* Finish zero length reads right here */
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if (auio->uio_resid == 0) {
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td->td_retval[0] = 0;
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return(0);
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}
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auio->uio_rw = UIO_READ;
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auio->uio_offset = offset;
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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 = auio->uio_resid;
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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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}
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/*
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* Write system call
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*/
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#ifndef _SYS_SYSPROTO_H_
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struct write_args {
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int fd;
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const void *buf;
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size_t nbyte;
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};
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#endif
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int
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write(td, uap)
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struct thread *td;
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struct write_args *uap;
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{
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struct uio auio;
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struct iovec aiov;
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int error;
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if (uap->nbyte > INT_MAX)
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return (EINVAL);
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aiov.iov_base = (void *)(uintptr_t)uap->buf;
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aiov.iov_len = uap->nbyte;
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auio.uio_iov = &aiov;
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auio.uio_iovcnt = 1;
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auio.uio_resid = uap->nbyte;
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auio.uio_segflg = UIO_USERSPACE;
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error = kern_writev(td, uap->fd, &auio);
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return(error);
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}
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/*
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* Positioned write system call.
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*/
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#ifndef _SYS_SYSPROTO_H_
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struct pwrite_args {
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int fd;
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const 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
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int
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pwrite(td, uap)
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struct thread *td;
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struct pwrite_args *uap;
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{
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struct uio auio;
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struct iovec aiov;
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int error;
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if (uap->nbyte > INT_MAX)
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return (EINVAL);
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aiov.iov_base = (void *)(uintptr_t)uap->buf;
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aiov.iov_len = uap->nbyte;
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auio.uio_iov = &aiov;
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auio.uio_iovcnt = 1;
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auio.uio_resid = uap->nbyte;
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auio.uio_segflg = UIO_USERSPACE;
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error = kern_pwritev(td, uap->fd, &auio, uap->offset);
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return(error);
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}
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|
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/*
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* Gather write system call.
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*/
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#ifndef _SYS_SYSPROTO_H_
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struct writev_args {
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int fd;
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struct iovec *iovp;
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u_int iovcnt;
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};
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#endif
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int
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writev(struct thread *td, struct writev_args *uap)
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{
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struct uio *auio;
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int error;
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error = copyinuio(uap->iovp, uap->iovcnt, &auio);
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if (error)
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return (error);
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error = kern_writev(td, uap->fd, auio);
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free(auio, M_IOV);
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return (error);
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}
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|
|
int
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kern_writev(struct thread *td, int fd, struct uio *auio)
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{
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struct file *fp;
|
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int error;
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error = fget_write(td, fd, &fp);
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if (error)
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return (error);
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error = dofilewrite(td, fd, fp, auio, (off_t)-1, 0);
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fdrop(fp, td);
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return (error);
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}
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|
|
/*
|
|
* Gather positioned write system call.
|
|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
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|
struct pwritev_args {
|
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int fd;
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struct iovec *iovp;
|
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u_int iovcnt;
|
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off_t offset;
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};
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#endif
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|
int
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pwritev(struct thread *td, struct pwritev_args *uap)
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{
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struct uio *auio;
|
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int error;
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error = copyinuio(uap->iovp, uap->iovcnt, &auio);
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if (error)
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return (error);
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error = kern_pwritev(td, uap->fd, auio, uap->offset);
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free(auio, M_IOV);
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return (error);
|
|
}
|
|
|
|
int
|
|
kern_pwritev(td, fd, auio, offset)
|
|
struct thread *td;
|
|
struct uio *auio;
|
|
int fd;
|
|
off_t offset;
|
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{
|
|
struct file *fp;
|
|
int error;
|
|
|
|
error = fget_write(td, fd, &fp);
|
|
if (error)
|
|
return (error);
|
|
if (!(fp->f_ops->fo_flags & DFLAG_SEEKABLE))
|
|
error = ESPIPE;
|
|
else if (offset < 0 && fp->f_vnode->v_type != VCHR)
|
|
error = EINVAL;
|
|
else
|
|
error = dofilewrite(td, fd, fp, auio, offset, FOF_OFFSET);
|
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fdrop(fp, td);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Common code for writev and pwritev that writes data to
|
|
* a file using the passed in uio, offset, and flags.
|
|
*/
|
|
static int
|
|
dofilewrite(td, fd, fp, auio, offset, flags)
|
|
struct thread *td;
|
|
int fd;
|
|
struct file *fp;
|
|
struct uio *auio;
|
|
off_t offset;
|
|
int flags;
|
|
{
|
|
ssize_t cnt;
|
|
int error;
|
|
#ifdef KTRACE
|
|
struct uio *ktruio = NULL;
|
|
#endif
|
|
|
|
auio->uio_rw = UIO_WRITE;
|
|
auio->uio_td = td;
|
|
auio->uio_offset = offset;
|
|
#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, flags, td))) {
|
|
if (auio->uio_resid != cnt && (error == ERESTART ||
|
|
error == EINTR || error == EWOULDBLOCK))
|
|
error = 0;
|
|
/* Socket layer is responsible for issuing SIGPIPE. */
|
|
if (fp->f_type != DTYPE_SOCKET && 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(fd, UIO_WRITE, ktruio, error);
|
|
}
|
|
#endif
|
|
td->td_retval[0] = cnt;
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Ioctl system call.
|
|
*/
|
|
#ifndef _SYS_SYSPROTO_H_
|
|
struct ioctl_args {
|
|
int fd;
|
|
u_long com;
|
|
caddr_t data;
|
|
};
|
|
#endif
|
|
/* ARGSUSED */
|
|
int
|
|
ioctl(struct thread *td, struct ioctl_args *uap)
|
|
{
|
|
u_long com;
|
|
int arg, error;
|
|
u_int size;
|
|
caddr_t data;
|
|
|
|
if (uap->com > 0xffffffff) {
|
|
printf(
|
|
"WARNING pid %d (%s): ioctl sign-extension ioctl %lx\n",
|
|
td->td_proc->p_pid, td->td_proc->p_comm, uap->com);
|
|
uap->com &= 0xffffffff;
|
|
}
|
|
com = uap->com;
|
|
|
|
/*
|
|
* 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) ||
|
|
((com & (IOC_VOID | IOC_IN | IOC_OUT)) == 0) ||
|
|
#if defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
|
|
((com & IOC_OUT) && size == 0) ||
|
|
#else
|
|
((com & (IOC_IN | IOC_OUT)) && size == 0) ||
|
|
#endif
|
|
((com & IOC_VOID) && size > 0 && size != sizeof(int)))
|
|
return (ENOTTY);
|
|
|
|
if (size > 0) {
|
|
if (!(com & IOC_VOID))
|
|
data = malloc((u_long)size, M_IOCTLOPS, M_WAITOK);
|
|
else {
|
|
/* Integer argument. */
|
|
arg = (intptr_t)uap->data;
|
|
data = (void *)&arg;
|
|
size = 0;
|
|
}
|
|
} else
|
|
data = (void *)&uap->data;
|
|
if (com & IOC_IN) {
|
|
error = copyin(uap->data, data, (u_int)size);
|
|
if (error) {
|
|
if (size > 0)
|
|
free(data, M_IOCTLOPS);
|
|
return (error);
|
|
}
|
|
} else if (com & IOC_OUT) {
|
|
/*
|
|
* Zero the buffer so the user always
|
|
* gets back something deterministic.
|
|
*/
|
|
bzero(data, size);
|
|
}
|
|
|
|
error = kern_ioctl(td, uap->fd, com, data);
|
|
|
|
if (error == 0 && (com & IOC_OUT))
|
|
error = copyout(data, uap->data, (u_int)size);
|
|
|
|
if (size > 0)
|
|
free(data, M_IOCTLOPS);
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
kern_ioctl(struct thread *td, int fd, u_long com, caddr_t data)
|
|
{
|
|
struct file *fp;
|
|
struct filedesc *fdp;
|
|
int error;
|
|
int tmp;
|
|
|
|
if ((error = fget(td, fd, &fp)) != 0)
|
|
return (error);
|
|
if ((fp->f_flag & (FREAD | FWRITE)) == 0) {
|
|
fdrop(fp, td);
|
|
return (EBADF);
|
|
}
|
|
fdp = td->td_proc->p_fd;
|
|
switch (com) {
|
|
case FIONCLEX:
|
|
FILEDESC_LOCK_FAST(fdp);
|
|
fdp->fd_ofileflags[fd] &= ~UF_EXCLOSE;
|
|
FILEDESC_UNLOCK_FAST(fdp);
|
|
goto out;
|
|
case FIOCLEX:
|
|
FILEDESC_LOCK_FAST(fdp);
|
|
fdp->fd_ofileflags[fd] |= UF_EXCLOSE;
|
|
FILEDESC_UNLOCK_FAST(fdp);
|
|
goto out;
|
|
case FIONBIO:
|
|
FILE_LOCK(fp);
|
|
if ((tmp = *(int *)data))
|
|
fp->f_flag |= FNONBLOCK;
|
|
else
|
|
fp->f_flag &= ~FNONBLOCK;
|
|
FILE_UNLOCK(fp);
|
|
data = (void *)&tmp;
|
|
break;
|
|
case FIOASYNC:
|
|
FILE_LOCK(fp);
|
|
if ((tmp = *(int *)data))
|
|
fp->f_flag |= FASYNC;
|
|
else
|
|
fp->f_flag &= ~FASYNC;
|
|
FILE_UNLOCK(fp);
|
|
data = (void *)&tmp;
|
|
break;
|
|
}
|
|
|
|
error = fo_ioctl(fp, com, data, td->td_ucred, td);
|
|
out:
|
|
fdrop(fp, td);
|
|
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
|
|
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;
|
|
|
|
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);
|
|
|
|
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
|
|
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;
|
|
|
|
/*
|
|
* 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:
|
|
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
|
|
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);
|
|
}
|