mem.c revision 312394
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: stable/11/sys/sparc64/sparc64/mem.c 312394 2017-01-18 19:38:53Z jhb $"); 42 43/* 44 * Memory special file 45 * 46 * NOTE: other architectures support mmap()'ing the mem device; 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_phys.h> 69#include <vm/vm_kern.h> 70#include <vm/pmap.h> 71#include <vm/vm_extern.h> 72 73#include <machine/cache.h> 74#include <machine/md_var.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 uint32_t colors; 96 97 cnt = 0; 98 colors = 1; 99 error = 0; 100 ova = 0; 101 102 while (uio->uio_resid > 0 && error == 0) { 103 iov = uio->uio_iov; 104 if (iov->iov_len == 0) { 105 uio->uio_iov++; 106 uio->uio_iovcnt--; 107 if (uio->uio_iovcnt < 0) 108 panic("memrw"); 109 continue; 110 } 111 if (dev2unit(dev) == CDEV_MINOR_MEM) { 112 pa = uio->uio_offset & ~PAGE_MASK; 113 if (!is_physical_memory(pa)) { 114 error = EFAULT; 115 break; 116 } 117 118 off = uio->uio_offset & PAGE_MASK; 119 cnt = PAGE_SIZE - ((vm_offset_t)iov->iov_base & 120 PAGE_MASK); 121 cnt = ulmin(cnt, PAGE_SIZE - off); 122 cnt = ulmin(cnt, iov->iov_len); 123 124 m = vm_phys_paddr_to_vm_page(pa); 125 if (m != NULL) { 126 if (ova == 0) { 127 if (dcache_color_ignore == 0) 128 colors = DCACHE_COLORS; 129 ova = kva_alloc(PAGE_SIZE * colors); 130 if (ova == 0) { 131 error = ENOMEM; 132 break; 133 } 134 } 135 if (colors != 1 && m->md.color != -1) 136 va = ova + m->md.color * PAGE_SIZE; 137 else 138 va = ova; 139 pmap_qenter(va, &m, 1); 140 error = uiomove((void *)(va + off), cnt, 141 uio); 142 pmap_qremove(va, 1); 143 } else { 144 va = TLB_PHYS_TO_DIRECT(pa); 145 error = uiomove((void *)(va + off), cnt, 146 uio); 147 } 148 break; 149 } else if (dev2unit(dev) == CDEV_MINOR_KMEM) { 150 va = trunc_page(uio->uio_offset); 151 eva = round_page(uio->uio_offset + iov->iov_len); 152 153 /* 154 * Make sure that all of the pages are currently 155 * resident so we don't create any zero fill pages. 156 */ 157 for (; va < eva; va += PAGE_SIZE) 158 if (pmap_kextract(va) == 0) 159 return (EFAULT); 160 161 prot = (uio->uio_rw == UIO_READ) ? VM_PROT_READ : 162 VM_PROT_WRITE; 163 va = uio->uio_offset; 164 if (va < VM_MIN_DIRECT_ADDRESS && 165 kernacc((void *)va, iov->iov_len, prot) == FALSE) 166 return (EFAULT); 167 168 error = uiomove((void *)va, iov->iov_len, uio); 169 break; 170 } 171 /* else panic! */ 172 } 173 if (ova != 0) 174 kva_free(ova, PAGE_SIZE * colors); 175 return (error); 176} 177