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
memrw(struct cdev * dev,struct uio * uio,int flags)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, PAGE_SIZE, v,
118 VM_MEMATTR_DEFAULT);
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
memmmap(struct cdev * dev,vm_ooffset_t offset,vm_paddr_t * paddr,int prot __unused,vm_memattr_t * memattr __unused)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
memioctl_md(struct cdev * dev __unused,u_long cmd __unused,caddr_t data __unused,int flags __unused,struct thread * td __unused)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