1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1988 University of Utah. 5 * Copyright (c) 1982, 1986, 1990 The Regents of the University of California. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the Systems Programming Group of the University of Utah Computer 10 * Science Department, and code derived from software contributed to 11 * Berkeley by William Jolitz. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * from: Utah $Hdr: mem.c 1.13 89/10/08$ 38 */ 39 40 #include <sys/cdefs.h> 41 /* 42 * Memory special file 43 */ 44 45 #include <sys/param.h> 46 #include <sys/conf.h> 47 #include <sys/fcntl.h> 48 #include <sys/ioccom.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/signalvar.h> 57 #include <sys/sx.h> 58 #include <sys/systm.h> 59 #include <sys/uio.h> 60 61 #include <vm/vm.h> 62 #include <vm/vm_param.h> 63 #include <vm/vm_page.h> 64 #include <vm/vm_phys.h> 65 #include <vm/vm_dumpset.h> 66 #include <vm/pmap.h> 67 #include <vm/vm_extern.h> 68 69 #include <machine/memdev.h> 70 71 /* 72 * Used in /dev/mem drivers and elsewhere 73 */ 74 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors"); 75 76 struct mem_range_softc mem_range_softc; 77 78 static struct sx tmppt_lock; 79 SX_SYSINIT(tmppt, &tmppt_lock, "mem4map"); 80 81 /* ARGSUSED */ 82 int 83 memrw(struct cdev *dev, struct uio *uio, int flags) 84 { 85 int o; 86 u_int c = 0, v; 87 struct iovec *iov; 88 int error = 0; 89 vm_offset_t addr, eaddr; 90 91 while (uio->uio_resid > 0 && error == 0) { 92 iov = uio->uio_iov; 93 if (iov->iov_len == 0) { 94 uio->uio_iov++; 95 uio->uio_iovcnt--; 96 if (uio->uio_iovcnt < 0) 97 panic("memrw"); 98 continue; 99 } 100 if (dev2unit(dev) == CDEV_MINOR_MEM) { 101 int i; 102 int address_valid = 0; 103 104 v = uio->uio_offset; 105 v &= ~PAGE_MASK; 106 for (i = 0; dump_avail[i] || dump_avail[i + 1]; 107 i += 2) { 108 if (v >= dump_avail[i] && 109 v < dump_avail[i + 1]) { 110 address_valid = 1; 111 break; 112 } 113 } 114 if (!address_valid) 115 return (EINVAL); 116 sx_xlock(&tmppt_lock); 117 pmap_kenter((vm_offset_t)_tmppt, v); 118 pmap_tlb_flush(kernel_pmap, (vm_offset_t)_tmppt); 119 o = (int)uio->uio_offset & PAGE_MASK; 120 c = (u_int)(PAGE_SIZE - ((int)iov->iov_base & PAGE_MASK)); 121 c = min(c, (u_int)(PAGE_SIZE - o)); 122 c = min(c, (u_int)iov->iov_len); 123 error = uiomove((caddr_t)&_tmppt[o], (int)c, uio); 124 pmap_qremove((vm_offset_t)_tmppt, 1); 125 sx_xunlock(&tmppt_lock); 126 continue; 127 } 128 else if (dev2unit(dev) == CDEV_MINOR_KMEM) { 129 c = iov->iov_len; 130 131 /* 132 * Make sure that all of the pages are currently 133 * resident so that we don't create any zero-fill 134 * pages. 135 */ 136 addr = trunc_page(uio->uio_offset); 137 eaddr = round_page(uio->uio_offset + c); 138 139 for (; addr < eaddr; addr += PAGE_SIZE) 140 if (pmap_extract(kernel_pmap, addr) == 0) 141 return (EFAULT); 142 if (!kernacc((caddr_t)(int)uio->uio_offset, c, 143 uio->uio_rw == UIO_READ ? 144 VM_PROT_READ : VM_PROT_WRITE)) 145 return (EFAULT); 146 error = uiomove((caddr_t)(int)uio->uio_offset, (int)c, uio); 147 continue; 148 } 149 /* else panic! */ 150 } 151 return (error); 152 } 153 154 /* 155 * allow user processes to MMAP some memory sections 156 * instead of going through read/write 157 */ 158 /* ARGSUSED */ 159 160 int 161 memmmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr, 162 int prot __unused, vm_memattr_t *memattr __unused) 163 { 164 if (dev2unit(dev) == CDEV_MINOR_MEM) { 165 *paddr = offset; 166 return (0); 167 } 168 return (-1); 169 } 170 171 int 172 memioctl_md(struct cdev *dev __unused, u_long cmd __unused, 173 caddr_t data __unused, int flags __unused, struct thread *td __unused) 174 { 175 return (ENOTTY); 176 } 177