1 /*-
2 * Copyright (c) 2014 Andrew Turner
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 */
27
28 #include <sys/param.h>
29 #include <sys/systm.h>
30 #include <sys/conf.h>
31 #include <sys/malloc.h>
32 #include <sys/memrange.h>
33 #include <sys/uio.h>
34
35 #include <machine/memdev.h>
36 #include <machine/vmparam.h>
37
38 #include <vm/vm.h>
39 #include <vm/pmap.h>
40 #include <vm/vm_extern.h>
41 #include <vm/vm_page.h>
42
43 struct mem_range_softc mem_range_softc;
44
45 int
memrw(struct cdev * dev,struct uio * uio,int flags)46 memrw(struct cdev *dev, struct uio *uio, int flags)
47 {
48 ssize_t orig_resid;
49 vm_offset_t off, v;
50 struct iovec *iov;
51 struct vm_page m;
52 vm_page_t marr;
53 vm_prot_t prot;
54 u_int cnt;
55 int error;
56
57 error = 0;
58 orig_resid = uio->uio_resid;
59 while (uio->uio_resid > 0 && error == 0) {
60 iov = uio->uio_iov;
61 if (iov->iov_len == 0) {
62 uio->uio_iov++;
63 uio->uio_iovcnt--;
64 if (uio->uio_iovcnt < 0)
65 panic("memrw");
66 continue;
67 }
68
69 v = uio->uio_offset;
70 off = v & PAGE_MASK;
71 cnt = ulmin(iov->iov_len, PAGE_SIZE - (u_int)off);
72 if (cnt == 0)
73 continue;
74
75 switch(dev2unit(dev)) {
76 case CDEV_MINOR_KMEM:
77 /* If the address is in the DMAP just copy it */
78 if (VIRT_IN_DMAP(v)) {
79 error = uiomove((void *)v, cnt, uio);
80 break;
81 }
82
83 switch (uio->uio_rw) {
84 case UIO_READ:
85 prot = VM_PROT_READ;
86 break;
87 case UIO_WRITE:
88 prot = VM_PROT_WRITE;
89 break;
90 }
91
92 if (!kernacc((void *)v, cnt, prot)) {
93 error = EFAULT;
94 break;
95 }
96
97 /* Get the physical address to read */
98 v = pmap_extract(kernel_pmap, v);
99 if (v == 0) {
100 error = EFAULT;
101 break;
102 }
103
104 /* FALLTHROUGH */
105 case CDEV_MINOR_MEM:
106 /* If within the DMAP use this to copy from */
107 if (PHYS_IN_DMAP(v)) {
108 v = PHYS_TO_DMAP(v);
109 error = uiomove((void *)v, cnt, uio);
110 break;
111 }
112
113 /* Have uiomove_fromphys handle the data */
114 m.phys_addr = trunc_page(v);
115 marr = &m;
116 uiomove_fromphys(&marr, off, cnt, uio);
117 break;
118 }
119 }
120
121 /*
122 * Don't return error if any byte was written. Read and write
123 * can return error only if no i/o was performed.
124 */
125 if (uio->uio_resid != orig_resid)
126 error = 0;
127
128 return (error);
129 }
130
131 /*
132 * Allow user processes to MMAP some memory sections
133 * instead of going through read/write.
134 */
135 int
memmmap(struct cdev * dev,vm_ooffset_t offset,vm_paddr_t * paddr,int prot __unused,vm_memattr_t * memattr __unused)136 memmmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
137 int prot __unused, vm_memattr_t *memattr __unused)
138 {
139 if (dev2unit(dev) == CDEV_MINOR_MEM) {
140 *paddr = offset;
141 return (0);
142 }
143 return (-1);
144 }
145
146 int
memioctl_md(struct cdev * dev __unused,u_long cmd __unused,caddr_t data __unused,int flags __unused,struct thread * td __unused)147 memioctl_md(struct cdev *dev __unused, u_long cmd __unused,
148 caddr_t data __unused, int flags __unused, struct thread *td __unused)
149 {
150 return (ENOTTY);
151 }
152