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/sx.h> 59 #include <sys/systm.h> 60 #include <sys/uio.h> 61 62 #include <vm/vm.h> 63 #include <vm/pmap.h> 64 #include <vm/vm_extern.h> 65 66 #include <machine/acle-compat.h> 67 #include <machine/memdev.h> 68 #include <machine/vmparam.h> 69 70 /* 71 * Used in /dev/mem drivers and elsewhere 72 */ 73 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors"); 74 75 struct mem_range_softc mem_range_softc; 76 77 static struct sx tmppt_lock; 78 SX_SYSINIT(tmppt, &tmppt_lock, "mem4map"); 79 80 /* ARGSUSED */ 81 int 82 memrw(struct cdev *dev, struct uio *uio, int flags) 83 { 84 int o; 85 u_int c = 0, v; 86 struct iovec *iov; 87 int error = 0; 88 vm_offset_t addr, eaddr; 89 90 while (uio->uio_resid > 0 && error == 0) { 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 int i; 101 int address_valid = 0; 102 103 v = uio->uio_offset; 104 v &= ~PAGE_MASK; 105 for (i = 0; dump_avail[i] || dump_avail[i + 1]; 106 i += 2) { 107 if (v >= dump_avail[i] && 108 v < dump_avail[i + 1]) { 109 address_valid = 1; 110 break; 111 } 112 } 113 if (!address_valid) 114 return (EINVAL); 115 sx_xlock(&tmppt_lock); 116 pmap_kenter((vm_offset_t)_tmppt, v); 117 #if __ARM_ARCH >= 6 118 pmap_tlb_flush(kernel_pmap, (vm_offset_t)_tmppt); 119 #endif 120 o = (int)uio->uio_offset & PAGE_MASK; 121 c = (u_int)(PAGE_SIZE - ((int)iov->iov_base & PAGE_MASK)); 122 c = min(c, (u_int)(PAGE_SIZE - o)); 123 c = min(c, (u_int)iov->iov_len); 124 error = uiomove((caddr_t)&_tmppt[o], (int)c, uio); 125 pmap_qremove((vm_offset_t)_tmppt, 1); 126 sx_xunlock(&tmppt_lock); 127 continue; 128 } 129 else if (dev2unit(dev) == CDEV_MINOR_KMEM) { 130 c = iov->iov_len; 131 132 /* 133 * Make sure that all of the pages are currently 134 * resident so that we don't create any zero-fill 135 * pages. 136 */ 137 addr = trunc_page(uio->uio_offset); 138 eaddr = round_page(uio->uio_offset + c); 139 140 for (; addr < eaddr; addr += PAGE_SIZE) 141 if (pmap_extract(kernel_pmap, addr) == 0) 142 return (EFAULT); 143 if (!kernacc((caddr_t)(int)uio->uio_offset, c, 144 uio->uio_rw == UIO_READ ? 145 VM_PROT_READ : VM_PROT_WRITE)) 146 return (EFAULT); 147 error = uiomove((caddr_t)(int)uio->uio_offset, (int)c, uio); 148 continue; 149 } 150 /* else panic! */ 151 } 152 return (error); 153 } 154 155 /* 156 * allow user processes to MMAP some memory sections 157 * instead of going through read/write 158 */ 159 /* ARGSUSED */ 160 161 int 162 memmmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, 163 int prot __unused, vm_memattr_t *memattr __unused) 164 { 165 if (dev2unit(dev) == CDEV_MINOR_MEM) 166 *paddr = offset; 167 else if (dev2unit(dev) == CDEV_MINOR_KMEM) 168 *paddr = vtophys(offset); 169 /* else panic! */ 170 return (0); 171 } 172