/*-
* Copyright (c) 2002, 2008, 2010 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas, Joerg Sonnenberger and Mindaugas Rasiukevicius.
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* Special /dev/{mem,kmem,zero,null} memory devices.
*/
#ifndef __HAVE_MM_MD_CACHE_ALIASING
/* KVA for mappings during I/O. */
dev_mem_addr = uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
UVM_KMF_VAONLY|UVM_KMF_WAITVA);
KASSERT(dev_mem_addr != 0);
#else
dev_mem_addr = 0;
#endif
}
/*
* dev_mem_getva: get a special virtual address. If architecture requires,
* allocate VA according to PA, which avoids cache-aliasing issues. Use a
* constant, general mapping address otherwise.
*/
static inline vaddr_t
dev_mem_getva(paddr_t pa, int color)
{
#ifdef __HAVE_MM_MD_CACHE_ALIASING
return uvm_km_alloc(kernel_map, PAGE_SIZE,
color & uvmexp.colormask,
UVM_KMF_VAONLY | UVM_KMF_WAITVA | UVM_KMF_COLORMATCH);
#else
return dev_mem_addr;
#endif
}
#ifdef __HAVE_MM_MD_DIRECT_MAPPED_IO
paddr_t paddr;
/* MD case: is this is a directly mapped address? */
if (mm_md_direct_mapped_io(addr, &paddr)) {
/* If so, validate physical address. */
error = mm_md_physacc(paddr, prot);
if (error) {
return error;
}
md_kva = true;
}
#endif
if (!md_kva) {
bool checked = false;
#ifdef __HAVE_MM_MD_KERNACC
/* MD check for the address. */
error = mm_md_kernacc(addr, prot, &checked);
if (error) {
return error;
}
#endif
/* UVM check for the address (unless MD indicated to not). */
if (!checked && !uvm_kernacc(addr, len, prot)) {
return EFAULT;
}
}
error = uiomove(addr, len, uio);
return error;
}
/*
* dev_zero_readwrite: helper for DEV_ZERO (/dev/null) case of R/W.
*/
static inline int
dev_zero_readwrite(struct uio *uio, struct iovec *iov)
{
size_t len;
/* Nothing to do for the write case. */
if (uio->uio_rw == UIO_WRITE) {
uio->uio_resid = 0;
return 0;
}
/*
* Read in page-by-page basis, caller will continue.
* Cut appropriately for a single/last-iteration cases.
*/
len = MIN(iov->iov_len, PAGE_SIZE);
return uiomove(dev_zero_page, len, uio);
}
/*
* mm_readwrite: general memory R/W function.
*/
static int
mm_readwrite(dev_t dev, struct uio *uio, int flags)
{
struct iovec *iov;
int error;
#ifdef __HAVE_MM_MD_READWRITE
/* If defined - there are extra MD cases. */
switch (minor(dev)) {
case DEV_MEM:
case DEV_KMEM:
case DEV_NULL:
case DEV_ZERO:
#if defined(COMPAT_16) && defined(__arm)
case _DEV_ZERO_oARM:
#endif
break;
default:
return mm_md_readwrite(dev, uio);
}
#endif
error = 0;
while (uio->uio_resid > 0 && error == 0) {
iov = uio->uio_iov;
if (iov->iov_len == 0) {
/* Processed; next I/O vector. */
uio->uio_iov++;
uio->uio_iovcnt--;
KASSERT(uio->uio_iovcnt >= 0);
continue;
}
/* Helper functions will process in page-by-page basis. */
switch (minor(dev)) {
case DEV_MEM:
error = dev_mem_readwrite(uio, iov);
break;
case DEV_KMEM:
error = dev_kmem_readwrite(uio, iov);
break;
case DEV_NULL:
if (uio->uio_rw == UIO_WRITE) {
uio->uio_resid = 0;
}
/* Break directly out of the loop. */
return 0;
case DEV_FULL:
if (uio->uio_rw == UIO_WRITE) {
return ENOSPC;
}
#if defined(COMPAT_16) && defined(__arm)
/* FALLTHROUGH */
case _DEV_ZERO_oARM:
#endif
/* FALLTHROUGH */
case DEV_ZERO:
error = dev_zero_readwrite(uio, iov);
break;
default:
error = ENXIO;
break;
}
}
return error;
}
/*
* mm_mmap: general mmap() handler.
*/
static paddr_t
mm_mmap(dev_t dev, off_t off, int acc)
{
vm_prot_t prot;
#ifdef __HAVE_MM_MD_MMAP
/* If defined - there are extra mmap() MD cases. */
switch (minor(dev)) {
case DEV_MEM:
case DEV_KMEM:
case DEV_NULL:
#if defined(COMPAT_16) && defined(__arm)
case _DEV_ZERO_oARM:
#endif
case DEV_ZERO:
break;
default:
return mm_md_mmap(dev, off, acc);
}
#endif
/*
* /dev/null does not make sense, /dev/kmem is volatile and
* /dev/zero is handled in mmap already.
*/
if (minor(dev) != DEV_MEM) {
return -1;
}
prot = 0;
if (acc & PROT_EXEC)
prot |= VM_PROT_EXECUTE;
if (acc & PROT_READ)
prot |= VM_PROT_READ;
if (acc & PROT_WRITE)
prot |= VM_PROT_WRITE;
/* Validate the physical address. */
if (mm_md_physacc(off, prot) != 0) {
return -1;
}
return off >> PGSHIFT;
}
static int
mm_ioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
{
switch (cmd) {
case FIONBIO:
/* We never block anyway. */
return 0;
case FIOSETOWN:
case FIOGETOWN:
case TIOCGPGRP:
case TIOCSPGRP:
case TIOCGETA:
return ENOTTY;
case FIOASYNC:
if ((*(int *)data) == 0) {
return 0;
}
/* FALLTHROUGH */
default:
return EOPNOTSUPP;
}
}
