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/ioccom.h> 50 #include <sys/kernel.h> 51 #include <sys/lock.h> 52 #include <sys/malloc.h> 53 #include <sys/memrange.h> 54 #include <sys/module.h> 55 #include <sys/mutex.h> 56 #include <sys/proc.h> 57 #include <sys/signalvar.h> 58 #include <sys/systm.h> 59 #include <sys/uio.h> 60 61 #include <vm/vm.h> 62 #include <vm/pmap.h> 63 #include <vm/vm_extern.h> 64 65 #include <machine/memdev.h> 66 #include <machine/vmparam.h> 67 68 /* 69 * Used in /dev/mem drivers and elsewhere 70 */ 71 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors"); 72 73 struct mem_range_softc mem_range_softc; 74 75 /* ARGSUSED */ 76 int 77 memrw(struct cdev *dev, struct uio *uio, int flags) 78 { 79 int o; 80 u_int c = 0, v; 81 struct iovec *iov; 82 int error = 0; 83 vm_offset_t addr, eaddr; 84 85 GIANT_REQUIRED; 86 87 while (uio->uio_resid > 0 && error == 0) { 88 iov = uio->uio_iov; 89 if (iov->iov_len == 0) { 90 uio->uio_iov++; 91 uio->uio_iovcnt--; 92 if (uio->uio_iovcnt < 0) 93 panic("memrw"); 94 continue; 95 } 96 if (dev2unit(dev) == CDEV_MINOR_MEM) { 97 int i; 98 int address_valid = 0; 99 100 v = uio->uio_offset; 101 v &= ~PAGE_MASK; 102 for (i = 0; dump_avail[i] || dump_avail[i + 1]; 103 i += 2) { 104 if (v >= dump_avail[i] && 105 v < dump_avail[i + 1]) { 106 address_valid = 1; 107 break; 108 } 109 } 110 if (!address_valid) 111 return (EINVAL); 112 pmap_kenter((vm_offset_t)_tmppt, v); 113 o = (int)uio->uio_offset & PAGE_MASK; 114 c = (u_int)(PAGE_SIZE - ((int)iov->iov_base & PAGE_MASK)); 115 c = min(c, (u_int)(PAGE_SIZE - o)); 116 c = min(c, (u_int)iov->iov_len); 117 error = uiomove((caddr_t)&_tmppt[o], (int)c, uio); 118 pmap_qremove((vm_offset_t)_tmppt, 1); 119 continue; 120 } 121 else if (dev2unit(dev) == CDEV_MINOR_KMEM) { 122 c = iov->iov_len; 123 124 /* 125 * Make sure that all of the pages are currently 126 * resident so that we don't create any zero-fill 127 * pages. 128 */ 129 addr = trunc_page(uio->uio_offset); 130 eaddr = round_page(uio->uio_offset + c); 131 132 for (; addr < eaddr; addr += PAGE_SIZE) 133 if (pmap_extract(kernel_pmap, addr) == 0) 134 return (EFAULT); 135 if (!kernacc((caddr_t)(int)uio->uio_offset, c, 136 uio->uio_rw == UIO_READ ? 137 VM_PROT_READ : VM_PROT_WRITE)) 138 #ifdef ARM_USE_SMALL_ALLOC 139 if (addr <= VM_MAXUSER_ADDRESS || 140 addr >= KERNBASE) 141 #endif 142 return (EFAULT); 143 error = uiomove((caddr_t)(int)uio->uio_offset, (int)c, uio); 144 continue; 145 } 146 /* else panic! */ 147 } 148 return (error); 149 } 150 151 /* 152 * allow user processes to MMAP some memory sections 153 * instead of going through read/write 154 */ 155 /* ARGSUSED */ 156 157 int 158 memmmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, 159 int prot __unused, vm_memattr_t *memattr __unused) 160 { 161 if (dev2unit(dev) == CDEV_MINOR_MEM) 162 *paddr = offset; 163 else if (dev2unit(dev) == CDEV_MINOR_KMEM) 164 *paddr = vtophys(offset); 165 /* else panic! */ 166 return (0); 167 } 168