1/*- 2 * Copyright (c) 1988 University of Utah. 3 * Copyright (c) 1982, 1986, 1990 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the Systems Programming Group of the University of Utah Computer 8 * Science Department, and code derived from software contributed to 9 * Berkeley by William Jolitz. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * from: Utah $Hdr: mem.c 1.13 89/10/08$ 36 * from: @(#)mem.c 7.2 (Berkeley) 5/9/91 37 * from: FreeBSD: src/sys/i386/i386/mem.c,v 1.94 2001/09/26 38 */ 39 40#include <sys/cdefs.h> 41__FBSDID("$FreeBSD$"); 42 43/* 44 * Memory special file 45 * 46 * NOTE: other architectures support mmap()'ing the mem and kmem devices; this 47 * might cause illegal aliases to be created for the locked kernel page(s), so 48 * it is not implemented. 49 */ 50 51#include <sys/param.h> 52#include <sys/conf.h> 53#include <sys/fcntl.h> 54#include <sys/kernel.h> 55#include <sys/lock.h> 56#include <sys/malloc.h> 57#include <sys/memrange.h> 58#include <sys/module.h> 59#include <sys/mutex.h> 60#include <sys/proc.h> 61#include <sys/signalvar.h> 62#include <sys/systm.h> 63#include <sys/uio.h> 64 65#include <vm/vm.h> 66#include <vm/vm_param.h> 67#include <vm/vm_page.h> 68#include <vm/vm_kern.h> 69#include <vm/pmap.h> 70#include <vm/vm_extern.h> 71 72#include <machine/cache.h> 73#include <machine/md_var.h> 74#include <machine/pmap.h> 75#include <machine/tlb.h> 76 77#include <machine/memdev.h> 78 79struct mem_range_softc mem_range_softc; 80 81/* ARGSUSED */ 82int 83memrw(struct cdev *dev, struct uio *uio, int flags) 84{ 85 struct iovec *iov; 86 vm_offset_t eva; 87 vm_offset_t off; 88 vm_offset_t ova; 89 vm_offset_t va; 90 vm_prot_t prot; 91 vm_paddr_t pa; 92 vm_size_t cnt; 93 vm_page_t m; 94 int error; 95 int i; 96 uint32_t colors; 97 98 cnt = 0; 99 colors = 1; 100 error = 0; 101 ova = 0; 102 103 GIANT_REQUIRED; 104 105 while (uio->uio_resid > 0 && error == 0) { 106 iov = uio->uio_iov; 107 if (iov->iov_len == 0) { 108 uio->uio_iov++; 109 uio->uio_iovcnt--; 110 if (uio->uio_iovcnt < 0) 111 panic("memrw"); 112 continue; 113 } 114 if (dev2unit(dev) == CDEV_MINOR_MEM) { 115 pa = uio->uio_offset & ~PAGE_MASK; 116 if (!is_physical_memory(pa)) { 117 error = EFAULT; 118 break; 119 } 120 121 off = uio->uio_offset & PAGE_MASK; 122 cnt = PAGE_SIZE - ((vm_offset_t)iov->iov_base & 123 PAGE_MASK); 124 cnt = ulmin(cnt, PAGE_SIZE - off); 125 cnt = ulmin(cnt, iov->iov_len); 126 127 m = NULL; 128 for (i = 0; phys_avail[i] != 0; i += 2) { 129 if (pa >= phys_avail[i] && 130 pa < phys_avail[i + 1]) { 131 m = PHYS_TO_VM_PAGE(pa); 132 break; 133 } 134 } 135 136 if (m != NULL) { 137 if (ova == 0) { 138 if (dcache_color_ignore == 0) 139 colors = DCACHE_COLORS; 140 ova = kmem_alloc_wait(kernel_map, 141 PAGE_SIZE * colors); 142 } 143 if (colors != 1 && m->md.color != -1) 144 va = ova + m->md.color * PAGE_SIZE; 145 else 146 va = ova; 147 pmap_qenter(va, &m, 1); 148 error = uiomove((void *)(va + off), cnt, 149 uio); 150 pmap_qremove(va, 1); 151 } else { 152 va = TLB_PHYS_TO_DIRECT(pa); 153 error = uiomove((void *)(va + off), cnt, 154 uio); 155 } 156 break; 157 } else if (dev2unit(dev) == CDEV_MINOR_KMEM) { 158 va = trunc_page(uio->uio_offset); 159 eva = round_page(uio->uio_offset + iov->iov_len); 160 161 /* 162 * Make sure that all of the pages are currently 163 * resident so we don't create any zero fill pages. 164 */ 165 for (; va < eva; va += PAGE_SIZE) 166 if (pmap_kextract(va) == 0) 167 return (EFAULT); 168 169 prot = (uio->uio_rw == UIO_READ) ? VM_PROT_READ : 170 VM_PROT_WRITE; 171 va = uio->uio_offset; 172 if (va < VM_MIN_DIRECT_ADDRESS && 173 kernacc((void *)va, iov->iov_len, prot) == FALSE) 174 return (EFAULT); 175 176 error = uiomove((void *)va, iov->iov_len, uio); 177 break; 178 } 179 /* else panic! */ 180 } 181 if (ova != 0) 182 kmem_free_wakeup(kernel_map, ova, PAGE_SIZE * colors); 183 return (error); 184} 185