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
43struct mem_range_softc mem_range_softc;
44
45int
46memrw(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 */
135int
136memmmap(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
146int
147memioctl_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