freebsd-dev/sys/compat/cloudabi64/cloudabi64_fd.c
Ed Schouten 47cb4d7bd0 Add a utility macro for converting 64-bit pointers to native pointers.
Right now we're casting uint64_t's to native pointers. This isn't
causing any problems right now, but if we want to provide a 32-bit
compatibility layer that works on 64-bit systems as well, this will
cause problems. Casting a uint32_t to a 64-bit pointer throws a compiler
error.

Introduce a TO_PTR() macro that casts the value to uintptr_t before
casting it to a pointer.
2016-08-21 15:36:18 +00:00

146 lines
3.9 KiB
C

/*-
* Copyright (c) 2015 Nuxi, https://nuxi.nl/
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* 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)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/limits.h>
#include <sys/malloc.h>
#include <sys/syscallsubr.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <contrib/cloudabi/cloudabi64_types.h>
#include <compat/cloudabi64/cloudabi64_proto.h>
#include <compat/cloudabi64/cloudabi64_util.h>
/* Copies in 64-bit iovec structures from userspace. */
static int
cloudabi64_copyinuio(const cloudabi64_iovec_t *iovp, size_t iovcnt,
struct uio **uiop)
{
cloudabi64_iovec_t iovobj;
struct uio *uio;
struct iovec *iov;
size_t i;
int error;
/* Allocate uio and iovecs. */
if (iovcnt > UIO_MAXIOV)
return (EINVAL);
uio = malloc(sizeof(struct uio) + iovcnt * sizeof(struct iovec),
M_IOV, M_WAITOK);
iov = (struct iovec *)(uio + 1);
/* Initialize uio. */
uio->uio_iov = iov;
uio->uio_iovcnt = iovcnt;
uio->uio_segflg = UIO_USERSPACE;
uio->uio_offset = -1;
uio->uio_resid = 0;
/* Copy in iovecs. */
for (i = 0; i < iovcnt; i++) {
error = copyin(&iovp[i], &iovobj, sizeof(iovobj));
if (error != 0) {
free(uio, M_IOV);
return (error);
}
iov[i].iov_base = TO_PTR(iovobj.iov_base);
iov[i].iov_len = iovobj.iov_len;
if (iov[i].iov_len > INT64_MAX - uio->uio_resid) {
free(uio, M_IOV);
return (EINVAL);
}
uio->uio_resid += iov[i].iov_len;
}
*uiop = uio;
return (0);
}
int
cloudabi64_sys_fd_pread(struct thread *td,
struct cloudabi64_sys_fd_pread_args *uap)
{
struct uio *uio;
int error;
error = cloudabi64_copyinuio(uap->iov, uap->iovcnt, &uio);
if (error != 0)
return (error);
error = kern_preadv(td, uap->fd, uio, uap->offset);
free(uio, M_IOV);
return (error);
}
int
cloudabi64_sys_fd_pwrite(struct thread *td,
struct cloudabi64_sys_fd_pwrite_args *uap)
{
struct uio *uio;
int error;
error = cloudabi64_copyinuio(TO_PTR(uap->iov), uap->iovcnt, &uio);
if (error != 0)
return (error);
error = kern_pwritev(td, uap->fd, uio, uap->offset);
free(uio, M_IOV);
return (error);
}
int
cloudabi64_sys_fd_read(struct thread *td,
struct cloudabi64_sys_fd_read_args *uap)
{
struct uio *uio;
int error;
error = cloudabi64_copyinuio(uap->iov, uap->iovcnt, &uio);
if (error != 0)
return (error);
error = kern_readv(td, uap->fd, uio);
free(uio, M_IOV);
return (error);
}
int
cloudabi64_sys_fd_write(struct thread *td,
struct cloudabi64_sys_fd_write_args *uap)
{
struct uio *uio;
int error;
error = cloudabi64_copyinuio(TO_PTR(uap->iov), uap->iovcnt, &uio);
if (error != 0)
return (error);
error = kern_writev(td, uap->fd, uio);
free(uio, M_IOV);
return (error);
}