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new argument passing conventions. minor type size cleanup.
[unix-history] / usr / src / sys / kern / sys_generic.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
* the permission of UNIX System Laboratories, Inc.
*
* %sccs.include.redist.c%
*
* @(#)sys_generic.c 8.9 (Berkeley) %G%
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/filedesc.h>
#include <sys/ioctl.h>
#include <sys/file.h>
#include <sys/proc.h>
#include <sys/socketvar.h>
#include <sys/uio.h>
#include <sys/kernel.h>
#include <sys/stat.h>
#include <sys/malloc.h>
#ifdef KTRACE
#include <sys/ktrace.h>
#endif
#include <sys/mount.h>
#include <sys/syscallargs.h>
/*
* Read system call.
*/
/* ARGSUSED */
int
read(p, uap, retval)
struct proc *p;
register struct read_args /* {
syscallarg(int) fd;
syscallarg(char *) buf;
syscallarg(u_int) nbyte;
} */ *uap;
register_t *retval;
{
register struct file *fp;
register struct filedesc *fdp = p->p_fd;
struct uio auio;
struct iovec aiov;
long cnt, error = 0;
#ifdef KTRACE
struct iovec ktriov;
#endif
if (((u_int)SCARG(uap, fd)) >= fdp->fd_nfiles ||
(fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL ||
(fp->f_flag & FREAD) == 0)
return (EBADF);
aiov.iov_base = (caddr_t)SCARG(uap, buf);
aiov.iov_len = SCARG(uap, nbyte);
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_resid = SCARG(uap, nbyte);
auio.uio_rw = UIO_READ;
auio.uio_segflg = UIO_USERSPACE;
auio.uio_procp = p;
#ifdef KTRACE
/*
* if tracing, save a copy of iovec
*/
if (KTRPOINT(p, KTR_GENIO))
ktriov = aiov;
#endif
cnt = SCARG(uap, nbyte);
if (error = (*fp->f_ops->fo_read)(fp, &auio, fp->f_cred))
if (auio.uio_resid != cnt && (error == ERESTART ||
error == EINTR || error == EWOULDBLOCK))
error = 0;
cnt -= auio.uio_resid;
#ifdef KTRACE
if (KTRPOINT(p, KTR_GENIO) && error == 0)
ktrgenio(p->p_tracep, SCARG(uap, fd), UIO_READ, &ktriov,
cnt, error);
#endif
*retval = cnt;
return (error);
}
/*
* Scatter read system call.
*/
int
readv(p, uap, retval)
struct proc *p;
register struct readv_args /* {
syscallarg(int) fd;
syscallarg(struct iovec *) iovp;
syscallarg(u_int) iovcnt;
} */ *uap;
register_t *retval;
{
register struct file *fp;
register struct filedesc *fdp = p->p_fd;
struct uio auio;
register struct iovec *iov;
struct iovec *needfree;
struct iovec aiov[UIO_SMALLIOV];
long i, cnt, error = 0;
u_int iovlen;
#ifdef KTRACE
struct iovec *ktriov = NULL;
#endif
if (((u_int)SCARG(uap, fd)) >= fdp->fd_nfiles ||
(fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL ||
(fp->f_flag & FREAD) == 0)
return (EBADF);
/* note: can't use iovlen until iovcnt is validated */
iovlen = SCARG(uap, iovcnt) * sizeof (struct iovec);
if (SCARG(uap, iovcnt) > UIO_SMALLIOV) {
if (SCARG(uap, iovcnt) > UIO_MAXIOV)
return (EINVAL);
MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK);
needfree = iov;
} else {
iov = aiov;
needfree = NULL;
}
auio.uio_iov = iov;
auio.uio_iovcnt = SCARG(uap, iovcnt);
auio.uio_rw = UIO_READ;
auio.uio_segflg = UIO_USERSPACE;
auio.uio_procp = p;
if (error = copyin((caddr_t)SCARG(uap, iovp), (caddr_t)iov, iovlen))
goto done;
auio.uio_resid = 0;
for (i = 0; i < SCARG(uap, iovcnt); i++) {
if (auio.uio_resid + iov->iov_len < auio.uio_resid) {
error = EINVAL;
goto done;
}
auio.uio_resid += iov->iov_len;
iov++;
}
#ifdef KTRACE
/*
* if tracing, save a copy of iovec
*/
if (KTRPOINT(p, KTR_GENIO)) {
MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK);
bcopy((caddr_t)auio.uio_iov, (caddr_t)ktriov, iovlen);
}
#endif
cnt = auio.uio_resid;
if (error = (*fp->f_ops->fo_read)(fp, &auio, fp->f_cred))
if (auio.uio_resid != cnt && (error == ERESTART ||
error == EINTR || error == EWOULDBLOCK))
error = 0;
cnt -= auio.uio_resid;
#ifdef KTRACE
if (ktriov != NULL) {
if (error == 0)
ktrgenio(p->p_tracep, SCARG(uap, fd), UIO_READ, ktriov,
cnt, error);
FREE(ktriov, M_TEMP);
}
#endif
*retval = cnt;
done:
if (needfree)
FREE(needfree, M_IOV);
return (error);
}
/*
* Write system call
*/
int
write(p, uap, retval)
struct proc *p;
register struct write_args /* {
syscallarg(int) fd;
syscallarg(char *) buf;
syscallarg(u_int) nbyte;
} */ *uap;
register_t *retval;
{
register struct file *fp;
register struct filedesc *fdp = p->p_fd;
struct uio auio;
struct iovec aiov;
long cnt, error = 0;
#ifdef KTRACE
struct iovec ktriov;
#endif
if (((u_int)SCARG(uap, fd)) >= fdp->fd_nfiles ||
(fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL ||
(fp->f_flag & FWRITE) == 0)
return (EBADF);
aiov.iov_base = (caddr_t)SCARG(uap, buf);
aiov.iov_len = SCARG(uap, nbyte);
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_resid = SCARG(uap, nbyte);
auio.uio_rw = UIO_WRITE;
auio.uio_segflg = UIO_USERSPACE;
auio.uio_procp = p;
#ifdef KTRACE
/*
* if tracing, save a copy of iovec
*/
if (KTRPOINT(p, KTR_GENIO))
ktriov = aiov;
#endif
cnt = SCARG(uap, nbyte);
if (error = (*fp->f_ops->fo_write)(fp, &auio, fp->f_cred)) {
if (auio.uio_resid != cnt && (error == ERESTART ||
error == EINTR || error == EWOULDBLOCK))
error = 0;
if (error == EPIPE)
psignal(p, SIGPIPE);
}
cnt -= auio.uio_resid;
#ifdef KTRACE
if (KTRPOINT(p, KTR_GENIO) && error == 0)
ktrgenio(p->p_tracep, SCARG(uap, fd), UIO_WRITE,
&ktriov, cnt, error);
#endif
*retval = cnt;
return (error);
}
/*
* Gather write system call
*/
int
writev(p, uap, retval)
struct proc *p;
register struct writev_args /* {
syscallarg(int) fd;
syscallarg(struct iovec *) iovp;
syscallarg(u_int) iovcnt;
} */ *uap;
register_t *retval;
{
register struct file *fp;
register struct filedesc *fdp = p->p_fd;
struct uio auio;
register struct iovec *iov;
struct iovec *needfree;
struct iovec aiov[UIO_SMALLIOV];
long i, cnt, error = 0;
u_int iovlen;
#ifdef KTRACE
struct iovec *ktriov = NULL;
#endif
if (((u_int)SCARG(uap, fd)) >= fdp->fd_nfiles ||
(fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL ||
(fp->f_flag & FWRITE) == 0)
return (EBADF);
/* note: can't use iovlen until iovcnt is validated */
iovlen = SCARG(uap, iovcnt) * sizeof (struct iovec);
if (SCARG(uap, iovcnt) > UIO_SMALLIOV) {
if (SCARG(uap, iovcnt) > UIO_MAXIOV)
return (EINVAL);
MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK);
needfree = iov;
} else {
iov = aiov;
needfree = NULL;
}
auio.uio_iov = iov;
auio.uio_iovcnt = SCARG(uap, iovcnt);
auio.uio_rw = UIO_WRITE;
auio.uio_segflg = UIO_USERSPACE;
auio.uio_procp = p;
if (error = copyin((caddr_t)SCARG(uap, iovp), (caddr_t)iov, iovlen))
goto done;
auio.uio_resid = 0;
for (i = 0; i < SCARG(uap, iovcnt); i++) {
if (auio.uio_resid + iov->iov_len < auio.uio_resid) {
error = EINVAL;
goto done;
}
auio.uio_resid += iov->iov_len;
iov++;
}
#ifdef KTRACE
/*
* if tracing, save a copy of iovec
*/
if (KTRPOINT(p, KTR_GENIO)) {
MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK);
bcopy((caddr_t)auio.uio_iov, (caddr_t)ktriov, iovlen);
}
#endif
cnt = auio.uio_resid;
if (error = (*fp->f_ops->fo_write)(fp, &auio, fp->f_cred)) {
if (auio.uio_resid != cnt && (error == ERESTART ||
error == EINTR || error == EWOULDBLOCK))
error = 0;
if (error == EPIPE)
psignal(p, SIGPIPE);
}
cnt -= auio.uio_resid;
#ifdef KTRACE
if (ktriov != NULL) {
if (error == 0)
ktrgenio(p->p_tracep, SCARG(uap, fd), UIO_WRITE,
ktriov, cnt, error);
FREE(ktriov, M_TEMP);
}
#endif
*retval = cnt;
done:
if (needfree)
FREE(needfree, M_IOV);
return (error);
}
/*
* Ioctl system call
*/
/* ARGSUSED */
int
ioctl(p, uap, retval)
struct proc *p;
register struct ioctl_args /* {
syscallarg(int) fd;
syscallarg(u_long) com;
syscallarg(caddr_t) data;
} */ *uap;
register_t *retval;
{
register struct file *fp;
register struct filedesc *fdp;
register u_long com;
register int error;
register u_int size;
caddr_t data, memp;
int tmp;
#define STK_PARAMS 128
char stkbuf[STK_PARAMS];
fdp = p->p_fd;
if ((u_int)SCARG(uap, fd) >= fdp->fd_nfiles ||
(fp = fdp->fd_ofiles[SCARG(uap, fd)]) == NULL)
return (EBADF);
if ((fp->f_flag & (FREAD | FWRITE)) == 0)
return (EBADF);
switch (com = SCARG(uap, com)) {
case FIONCLEX:
fdp->fd_ofileflags[SCARG(uap, fd)] &= ~UF_EXCLOSE;
return (0);
case FIOCLEX:
fdp->fd_ofileflags[SCARG(uap, fd)] |= UF_EXCLOSE;
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)
return (ENOTTY);
memp = NULL;
if (size > sizeof (stkbuf)) {
memp = (caddr_t)malloc((u_long)size, M_IOCTLOPS, M_WAITOK);
data = memp;
} else
data = stkbuf;
if (com&IOC_IN) {
if (size) {
error = copyin(SCARG(uap, data), data, (u_int)size);
if (error) {
if (memp)
free(memp, M_IOCTLOPS);
return (error);
}
} else
*(caddr_t *)data = SCARG(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 = SCARG(uap, data);
switch (com) {
case FIONBIO:
if (tmp = *(int *)data)
fp->f_flag |= FNONBLOCK;
else
fp->f_flag &= ~FNONBLOCK;
error = (*fp->f_ops->fo_ioctl)(fp, FIONBIO, (caddr_t)&tmp, p);
break;
case FIOASYNC:
if (tmp = *(int *)data)
fp->f_flag |= FASYNC;
else
fp->f_flag &= ~FASYNC;
error = (*fp->f_ops->fo_ioctl)(fp, FIOASYNC, (caddr_t)&tmp, p);
break;
case FIOSETOWN:
tmp = *(int *)data;
if (fp->f_type == DTYPE_SOCKET) {
((struct socket *)fp->f_data)->so_pgid = tmp;
error = 0;
break;
}
if (tmp <= 0) {
tmp = -tmp;
} else {
struct proc *p1 = pfind(tmp);
if (p1 == 0) {
error = ESRCH;
break;
}
tmp = p1->p_pgrp->pg_id;
}
error = (*fp->f_ops->fo_ioctl)
(fp, TIOCSPGRP, (caddr_t)&tmp, p);
break;
case FIOGETOWN:
if (fp->f_type == DTYPE_SOCKET) {
error = 0;
*(int *)data = ((struct socket *)fp->f_data)->so_pgid;
break;
}
error = (*fp->f_ops->fo_ioctl)(fp, TIOCGPGRP, data, p);
*(int *)data = -*(int *)data;
break;
default:
error = (*fp->f_ops->fo_ioctl)(fp, com, data, p);
/*
* Copy any data to user, size was
* already set and checked above.
*/
if (error == 0 && (com&IOC_OUT) && size)
error = copyout(data, SCARG(uap, data), (u_int)size);
break;
}
if (memp)
free(memp, M_IOCTLOPS);
return (error);
}
int selwait, nselcoll;
/*
* Select system call.
*/
int
select(p, uap, retval)
register struct proc *p;
register struct select_args /* {
syscallarg(u_int) nd;
syscallarg(fd_set *) in;
syscallarg(fd_set *) ou;
syscallarg(fd_set *) ex;
syscallarg(struct timeval *) tv;
} */ *uap;
register_t *retval;
{
fd_set ibits[3], obits[3];
struct timeval atv;
int s, ncoll, error, timo = 0;
u_int ni;
bzero((caddr_t)ibits, sizeof(ibits));
bzero((caddr_t)obits, sizeof(obits));
if (SCARG(uap, nd) > FD_SETSIZE)
return (EINVAL);
if (SCARG(uap, nd) > p->p_fd->fd_nfiles) {
/* forgiving; slightly wrong */
SCARG(uap, nd) = p->p_fd->fd_nfiles;
}
ni = howmany(SCARG(uap, nd), NFDBITS) * sizeof(fd_mask);
#define getbits(name, x) \
if (SCARG(uap, name) && (error = copyin((caddr_t)SCARG(uap, name), \
(caddr_t)&ibits[x], ni))) \
goto done;
getbits(in, 0);
getbits(ou, 1);
getbits(ex, 2);
#undef getbits
if (SCARG(uap, tv)) {
error = copyin((caddr_t)SCARG(uap, tv), (caddr_t)&atv,
sizeof (atv));
if (error)
goto done;
if (itimerfix(&atv)) {
error = EINVAL;
goto done;
}
s = splclock();
timevaladd(&atv, (struct timeval *)&time);
splx(s);
}
retry:
ncoll = nselcoll;
p->p_flag |= P_SELECT;
error = selscan(p, ibits, obits, SCARG(uap, nd), retval);
if (error || *retval)
goto done;
s = splhigh();
if (SCARG(uap, tv)) {
if (timercmp(&time, &atv, >=)) {
splx(s);
goto done;
}
/*
* If poll wait was tiny, this could be zero; we will
* have to round it up to avoid sleeping forever. If
* we retry below, the timercmp above will get us out.
* Note that if wait was 0, the timercmp will prevent
* us from getting here the first time.
*/
timo = hzto(&atv);
if (timo == 0)
timo = 1;
}
if ((p->p_flag & P_SELECT) == 0 || nselcoll != ncoll) {
splx(s);
goto retry;
}
p->p_flag &= ~P_SELECT;
error = tsleep((caddr_t)&selwait, PSOCK | PCATCH, "select", timo);
splx(s);
if (error == 0)
goto retry;
done:
p->p_flag &= ~P_SELECT;
/* select is not restarted after signals... */
if (error == ERESTART)
error = EINTR;
if (error == EWOULDBLOCK)
error = 0;
#define putbits(name, x) \
if (SCARG(uap, name) && (error2 = copyout((caddr_t)&obits[x], \
(caddr_t)SCARG(uap, name), ni))) \
error = error2;
if (error == 0) {
int error2;
putbits(in, 0);
putbits(ou, 1);
putbits(ex, 2);
#undef putbits
}
return (error);
}
int
selscan(p, ibits, obits, nfd, retval)
struct proc *p;
fd_set *ibits, *obits;
int nfd;
register_t *retval;
{
register struct filedesc *fdp = p->p_fd;
register int msk, i, j, fd;
register fd_mask bits;
struct file *fp;
int n = 0;
static int flag[3] = { FREAD, FWRITE, 0 };
for (msk = 0; msk < 3; msk++) {
for (i = 0; i < nfd; i += NFDBITS) {
bits = ibits[msk].fds_bits[i/NFDBITS];
while ((j = ffs(bits)) && (fd = i + --j) < nfd) {
bits &= ~(1 << j);
fp = fdp->fd_ofiles[fd];
if (fp == NULL)
return (EBADF);
if ((*fp->f_ops->fo_select)(fp, flag[msk], p)) {
FD_SET(fd, &obits[msk]);
n++;
}
}
}
}
*retval = n;
return (0);
}
/*ARGSUSED*/
int
seltrue(dev, flag, p)
dev_t dev;
int flag;
struct proc *p;
{
return (1);
}
/*
* Record a select request.
*/
void
selrecord(selector, sip)
struct proc *selector;
struct selinfo *sip;
{
struct proc *p;
pid_t mypid;
mypid = selector->p_pid;
if (sip->si_pid == mypid)
return;
if (sip->si_pid && (p = pfind(sip->si_pid)) &&
p->p_wchan == (caddr_t)&selwait)
sip->si_flags |= SI_COLL;
else
sip->si_pid = mypid;
}
/*
* Do a wakeup when a selectable event occurs.
*/
void
selwakeup(sip)
register struct selinfo *sip;
{
register struct proc *p;
int s;
if (sip->si_pid == 0)
return;
if (sip->si_flags & SI_COLL) {
nselcoll++;
sip->si_flags &= ~SI_COLL;
wakeup((caddr_t)&selwait);
}
p = pfind(sip->si_pid);
sip->si_pid = 0;
if (p != NULL) {
s = splhigh();
if (p->p_wchan == (caddr_t)&selwait) {
if (p->p_stat == SSLEEP)
setrunnable(p);
else
unsleep(p);
} else if (p->p_flag & P_SELECT)
p->p_flag &= ~P_SELECT;
splx(s);
}
}
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.