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 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 /* 43 * Memory special file 44 */ 45 46 #include <sys/param.h> 47 #include <sys/conf.h> 48 #include <sys/fcntl.h> 49 #include <sys/kernel.h> 50 #include <sys/lock.h> 51 #include <sys/malloc.h> 52 #include <sys/memrange.h> 53 #include <sys/module.h> 54 #include <sys/mutex.h> 55 #include <sys/proc.h> 56 #include <sys/msgbuf.h> 57 #include <sys/systm.h> 58 #include <sys/signalvar.h> 59 #include <sys/uio.h> 60 61 #include <machine/md_var.h> 62 #include <machine/vmparam.h> 63 64 #include <vm/vm.h> 65 #include <vm/pmap.h> 66 #include <vm/vm_extern.h> 67 #include <vm/vm_page.h> 68 69 #include <machine/memdev.h> 70 71 struct mem_range_softc mem_range_softc; 72 73 /* ARGSUSED */ 74 int 75 memrw(struct cdev *dev, struct uio *uio, int flags) 76 { 77 struct iovec *iov; 78 int error = 0; 79 vm_offset_t va, eva, off, v; 80 vm_prot_t prot; 81 struct vm_page m; 82 vm_page_t marr; 83 vm_size_t cnt; 84 85 cnt = 0; 86 error = 0; 87 88 GIANT_REQUIRED; 89 90 while (uio->uio_resid > 0 && !error) { 91 iov = uio->uio_iov; 92 if (iov->iov_len == 0) { 93 uio->uio_iov++; 94 uio->uio_iovcnt--; 95 if (uio->uio_iovcnt < 0) 96 panic("memrw"); 97 continue; 98 } 99 if (dev2unit(dev) == CDEV_MINOR_MEM) { 100 kmem_direct_mapped: v = uio->uio_offset; 101 102 off = uio->uio_offset & PAGE_MASK; 103 cnt = PAGE_SIZE - ((vm_offset_t)iov->iov_base & 104 PAGE_MASK); 105 cnt = min(cnt, PAGE_SIZE - off); 106 cnt = min(cnt, iov->iov_len); 107 108 if (mem_valid(v, cnt)) { 109 error = EFAULT; 110 break; 111 } 112 113 if (!pmap_dev_direct_mapped(v, cnt)) { 114 error = uiomove((void *)v, cnt, uio); 115 } else { 116 m.phys_addr = trunc_page(v); 117 marr = &m; 118 error = uiomove_fromphys(&marr, off, cnt, uio); 119 } 120 } 121 else if (dev2unit(dev) == CDEV_MINOR_KMEM) { 122 va = uio->uio_offset; 123 124 if ((va < VM_MIN_KERNEL_ADDRESS) || (va > virtual_end)) 125 goto kmem_direct_mapped; 126 127 va = trunc_page(uio->uio_offset); 128 eva = round_page(uio->uio_offset 129 + iov->iov_len); 130 131 /* 132 * Make sure that all the pages are currently resident 133 * so that we don't create any zero-fill pages. 134 */ 135 136 for (; va < eva; va += PAGE_SIZE) 137 if (pmap_extract(kernel_pmap, va) == 0) 138 return (EFAULT); 139 140 prot = (uio->uio_rw == UIO_READ) 141 ? VM_PROT_READ : VM_PROT_WRITE; 142 143 va = uio->uio_offset; 144 if (kernacc((void *) va, iov->iov_len, prot) 145 == FALSE) 146 return (EFAULT); 147 148 error = uiomove((void *)va, iov->iov_len, uio); 149 150 continue; 151 } 152 } 153 154 return (error); 155 } 156 157 /* 158 * allow user processes to MMAP some memory sections 159 * instead of going through read/write 160 */ 161 int 162 memmmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, 163 int prot, vm_memattr_t *memattr) 164 { 165 /* 166 * /dev/mem is the only one that makes sense through this 167 * interface. For /dev/kmem any physaddr we return here 168 * could be transient and hence incorrect or invalid at 169 * a later time. 170 */ 171 if (dev2unit(dev) != CDEV_MINOR_MEM) 172 return (-1); 173 174 /* Only direct-mapped addresses. */ 175 if (mem_valid(offset, 0) 176 && pmap_dev_direct_mapped(offset, 0)) 177 return (EFAULT); 178 179 *paddr = offset; 180 181 return (0); 182 } 183 184 void 185 dev_mem_md_init(void) 186 { 187 } 188