_kernel_uio.h

/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1982, 1986, 1993, 1994
 *  The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. 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
 * 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 REGENTS 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.
 *
 *  @(#)uio.h   8.5 (Berkeley) 2/22/94
 * $FreeBSD: head/sys/sys/uio.h 331621 2018-03-27 15:20:03Z brooks $
 */

#if !defined(_SYS_UIO_H_) || !defined(_KERNEL)
#error "must be included via <sys/uio.h> in kernel space"
#endif

struct uio {
    struct  iovec *uio_iov;     /* scatter/gather list */
    int uio_iovcnt;     /* length of scatter/gather list */
    off_t   uio_offset;     /* offset in target object */
    ssize_t uio_resid;      /* remaining bytes to process */
    enum    uio_seg uio_segflg; /* address space */
    enum    uio_rw uio_rw;      /* operation */
    struct  thread *uio_td;     /* owner */
};

/*
 * Limits
 *
 * N.B.: UIO_MAXIOV must be no less than IOV_MAX from <sys/syslimits.h>
 * which in turn must be no less than _XOPEN_IOV_MAX from <limits.h>.  If
 * we ever make this tunable (probably pointless), then IOV_MAX should be
 * removed from <sys/syslimits.h> and applications would be expected to use
 * sysconf(3) to find out the correct value, or else assume the worst
 * (_XOPEN_IOV_MAX).  Perhaps UIO_MAXIOV should be simply defined as
 * IOV_MAX.
 */
#define UIO_MAXIOV  1024        /* max 1K of iov's */

struct vm_object;
struct vm_page;
struct bus_dma_segment;

struct uio *cloneuio(struct uio *uiop);
int copyinfrom(const void * __restrict src, void * __restrict dst,
        size_t len, int seg);
int copyiniov(const struct iovec *iovp, u_int iovcnt, struct iovec **iov,
        int error);
int copyinstrfrom(const void * __restrict src, void * __restrict dst,
        size_t len, size_t * __restrict copied, int seg);
int copyinuio(const struct iovec *iovp, u_int iovcnt, struct uio **uiop);
int copyout_map(struct thread *td, vm_offset_t *addr, size_t sz);
int copyout_unmap(struct thread *td, vm_offset_t addr, size_t sz);
int physcopyin(void *src, vm_paddr_t dst, size_t len);
int physcopyout(vm_paddr_t src, void *dst, size_t len);
int physcopyin_vlist(struct bus_dma_segment *src, off_t offset,
        vm_paddr_t dst, size_t len);
int physcopyout_vlist(vm_paddr_t src, struct bus_dma_segment *dst,
        off_t offset, size_t len);
int uiomove(void *cp, int n, struct uio *uio);
int uiomove_frombuf(void *buf, int buflen, struct uio *uio);
int uiomove_fromphys(struct vm_page *ma[], vm_offset_t offset, int n,
        struct uio *uio);
int uiomove_nofault(void *cp, int n, struct uio *uio);
int uiomove_object(struct vm_object *obj, off_t obj_size, struct uio *uio);