mem.c revision 331017
1/*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1988 University of Utah. 5 * Copyright (c) 1982, 1986, 1990 The Regents of the University of California. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the Systems Programming Group of the University of Utah Computer 10 * Science Department, and code derived from software contributed to 11 * Berkeley by William Jolitz. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * from: Utah $Hdr: mem.c 1.13 89/10/08$ 38 * from: @(#)mem.c 7.2 (Berkeley) 5/9/91 39 * from: FreeBSD: src/sys/i386/i386/mem.c,v 1.94 2001/09/26 40 */ 41 42#include <sys/cdefs.h> 43__FBSDID("$FreeBSD: stable/11/sys/sparc64/sparc64/mem.c 331017 2018-03-15 19:08:33Z kevans $"); 44 45/* 46 * Memory special file 47 * 48 * NOTE: other architectures support mmap()'ing the mem device; this 49 * might cause illegal aliases to be created for the locked kernel page(s), so 50 * it is not implemented. 51 */ 52 53#include <sys/param.h> 54#include <sys/conf.h> 55#include <sys/fcntl.h> 56#include <sys/kernel.h> 57#include <sys/lock.h> 58#include <sys/malloc.h> 59#include <sys/memrange.h> 60#include <sys/module.h> 61#include <sys/mutex.h> 62#include <sys/proc.h> 63#include <sys/signalvar.h> 64#include <sys/systm.h> 65#include <sys/uio.h> 66#include <sys/vmmeter.h> 67 68#include <vm/vm.h> 69#include <vm/vm_param.h> 70#include <vm/vm_page.h> 71#include <vm/vm_phys.h> 72#include <vm/vm_kern.h> 73#include <vm/pmap.h> 74#include <vm/vm_extern.h> 75 76#include <machine/cache.h> 77#include <machine/md_var.h> 78#include <machine/tlb.h> 79 80#include <machine/memdev.h> 81 82struct mem_range_softc mem_range_softc; 83 84/* ARGSUSED */ 85int 86memrw(struct cdev *dev, struct uio *uio, int flags) 87{ 88 struct iovec *iov; 89 vm_offset_t eva; 90 vm_offset_t off; 91 vm_offset_t ova; 92 vm_offset_t va; 93 vm_prot_t prot; 94 vm_paddr_t pa; 95 vm_size_t cnt; 96 vm_page_t m; 97 int error; 98 uint32_t colors; 99 100 cnt = 0; 101 colors = 1; 102 error = 0; 103 ova = 0; 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 = vm_phys_paddr_to_vm_page(pa); 128 if (m != NULL) { 129 if (ova == 0) { 130 if (dcache_color_ignore == 0) 131 colors = DCACHE_COLORS; 132 ova = kva_alloc(PAGE_SIZE * colors); 133 if (ova == 0) { 134 error = ENOMEM; 135 break; 136 } 137 } 138 if (colors != 1 && m->md.color != -1) 139 va = ova + m->md.color * PAGE_SIZE; 140 else 141 va = ova; 142 pmap_qenter(va, &m, 1); 143 error = uiomove((void *)(va + off), cnt, 144 uio); 145 pmap_qremove(va, 1); 146 } else { 147 va = TLB_PHYS_TO_DIRECT(pa); 148 error = uiomove((void *)(va + off), cnt, 149 uio); 150 } 151 break; 152 } else if (dev2unit(dev) == CDEV_MINOR_KMEM) { 153 va = trunc_page(uio->uio_offset); 154 eva = round_page(uio->uio_offset + iov->iov_len); 155 156 /* 157 * Make sure that all of the pages are currently 158 * resident so we don't create any zero fill pages. 159 */ 160 for (; va < eva; va += PAGE_SIZE) 161 if (pmap_kextract(va) == 0) 162 return (EFAULT); 163 164 prot = (uio->uio_rw == UIO_READ) ? VM_PROT_READ : 165 VM_PROT_WRITE; 166 va = uio->uio_offset; 167 if (va < VM_MIN_DIRECT_ADDRESS && 168 kernacc((void *)va, iov->iov_len, prot) == FALSE) 169 return (EFAULT); 170 171 error = uiomove((void *)va, iov->iov_len, uio); 172 break; 173 } 174 /* else panic! */ 175 } 176 if (ova != 0) 177 kva_free(ova, PAGE_SIZE * colors); 178 return (error); 179} 180