mem.c revision 278746
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/10/sys/sparc64/sparc64/mem.c 278746 2015-02-14 08:44:12Z kib $"); 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 while (uio->uio_resid > 0 && error == 0) { 104 iov = uio->uio_iov; 105 if (iov->iov_len == 0) { 106 uio->uio_iov++; 107 uio->uio_iovcnt--; 108 if (uio->uio_iovcnt < 0) 109 panic("memrw"); 110 continue; 111 } 112 if (dev2unit(dev) == CDEV_MINOR_MEM) { 113 pa = uio->uio_offset & ~PAGE_MASK; 114 if (!is_physical_memory(pa)) { 115 error = EFAULT; 116 break; 117 } 118 119 off = uio->uio_offset & PAGE_MASK; 120 cnt = PAGE_SIZE - ((vm_offset_t)iov->iov_base & 121 PAGE_MASK); 122 cnt = ulmin(cnt, PAGE_SIZE - off); 123 cnt = ulmin(cnt, iov->iov_len); 124 125 m = NULL; 126 for (i = 0; phys_avail[i] != 0; i += 2) { 127 if (pa >= phys_avail[i] && 128 pa < phys_avail[i + 1]) { 129 m = PHYS_TO_VM_PAGE(pa); 130 break; 131 } 132 } 133 134 if (m != NULL) { 135 if (ova == 0) { 136 if (dcache_color_ignore == 0) 137 colors = DCACHE_COLORS; 138 ova = kva_alloc(PAGE_SIZE * colors); 139 if (ova == 0) { 140 error = ENOMEM; 141 break; 142 } 143 } 144 if (colors != 1 && m->md.color != -1) 145 va = ova + m->md.color * PAGE_SIZE; 146 else 147 va = ova; 148 pmap_qenter(va, &m, 1); 149 error = uiomove((void *)(va + off), cnt, 150 uio); 151 pmap_qremove(va, 1); 152 } else { 153 va = TLB_PHYS_TO_DIRECT(pa); 154 error = uiomove((void *)(va + off), cnt, 155 uio); 156 } 157 break; 158 } else if (dev2unit(dev) == CDEV_MINOR_KMEM) { 159 va = trunc_page(uio->uio_offset); 160 eva = round_page(uio->uio_offset + iov->iov_len); 161 162 /* 163 * Make sure that all of the pages are currently 164 * resident so we don't create any zero fill pages. 165 */ 166 for (; va < eva; va += PAGE_SIZE) 167 if (pmap_kextract(va) == 0) 168 return (EFAULT); 169 170 prot = (uio->uio_rw == UIO_READ) ? VM_PROT_READ : 171 VM_PROT_WRITE; 172 va = uio->uio_offset; 173 if (va < VM_MIN_DIRECT_ADDRESS && 174 kernacc((void *)va, iov->iov_len, prot) == FALSE) 175 return (EFAULT); 176 177 error = uiomove((void *)va, iov->iov_len, uio); 178 break; 179 } 180 /* else panic! */ 181 } 182 if (ova != 0) 183 kva_free(ova, PAGE_SIZE * colors); 184 return (error); 185} 186