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 *	from: FreeBSD: src/sys/i386/i386/mem.c,v 1.94 2001/09/26
38 */
39
40#include <sys/cdefs.h>
41__FBSDID("$FreeBSD: stable/11/sys/sparc64/sparc64/mem.c 331722 2018-03-29 02:50:57Z eadler $");
42
43/*
44 * Memory special file
45 *
46 * NOTE: other architectures support mmap()'ing the mem device; this
47 * might cause illegal aliases to be created for the locked kernel page(s), so
48 * it is not implemented.
49 */
50
51#include <sys/param.h>
52#include <sys/conf.h>
53#include <sys/fcntl.h>
54#include <sys/kernel.h>
55#include <sys/lock.h>
56#include <sys/malloc.h>
57#include <sys/memrange.h>
58#include <sys/module.h>
59#include <sys/mutex.h>
60#include <sys/proc.h>
61#include <sys/signalvar.h>
62#include <sys/systm.h>
63#include <sys/uio.h>
64#include <sys/vmmeter.h>
65
66#include <vm/vm.h>
67#include <vm/vm_param.h>
68#include <vm/vm_page.h>
69#include <vm/vm_phys.h>
70#include <vm/vm_kern.h>
71#include <vm/pmap.h>
72#include <vm/vm_extern.h>
73
74#include <machine/cache.h>
75#include <machine/md_var.h>
76#include <machine/tlb.h>
77
78#include <machine/memdev.h>
79
80struct mem_range_softc mem_range_softc;
81
82/* ARGSUSED */
83int
84memrw(struct cdev *dev, struct uio *uio, int flags)
85{
86	struct iovec *iov;
87	vm_offset_t eva;
88	vm_offset_t off;
89	vm_offset_t ova;
90	vm_offset_t va;
91	vm_prot_t prot;
92	vm_paddr_t pa;
93	vm_size_t cnt;
94	vm_page_t m;
95	int error;
96	uint32_t colors;
97
98	cnt = 0;
99	colors = 1;
100	error = 0;
101	ova = 0;
102
103	while (uio->uio_resid > 0 && error == 0) {
104		iov = uio->uio_iov;
105		if (iov->iov_len == 0) {
106			uio->uio_iov++;
107			uio->uio_iovcnt--;
108			if (uio->uio_iovcnt < 0)
109				panic("memrw");
110			continue;
111		}
112		if (dev2unit(dev) == CDEV_MINOR_MEM) {
113			pa = uio->uio_offset & ~PAGE_MASK;
114			if (!is_physical_memory(pa)) {
115				error = EFAULT;
116				break;
117			}
118
119			off = uio->uio_offset & PAGE_MASK;
120			cnt = PAGE_SIZE - ((vm_offset_t)iov->iov_base &
121			    PAGE_MASK);
122			cnt = ulmin(cnt, PAGE_SIZE - off);
123			cnt = ulmin(cnt, iov->iov_len);
124
125			m = vm_phys_paddr_to_vm_page(pa);
126			if (m != NULL) {
127				if (ova == 0) {
128					if (dcache_color_ignore == 0)
129						colors = DCACHE_COLORS;
130					ova = kva_alloc(PAGE_SIZE * colors);
131					if (ova == 0) {
132						error = ENOMEM;
133						break;
134					}
135				}
136				if (colors != 1 && m->md.color != -1)
137					va = ova + m->md.color * PAGE_SIZE;
138				else
139					va = ova;
140				pmap_qenter(va, &m, 1);
141				error = uiomove((void *)(va + off), cnt,
142				    uio);
143				pmap_qremove(va, 1);
144			} else {
145				va = TLB_PHYS_TO_DIRECT(pa);
146				error = uiomove((void *)(va + off), cnt,
147				    uio);
148			}
149			break;
150		} else if (dev2unit(dev) == CDEV_MINOR_KMEM) {
151			va = trunc_page(uio->uio_offset);
152			eva = round_page(uio->uio_offset + iov->iov_len);
153
154			/*
155			 * Make sure that all of the pages are currently
156			 * resident so we don't create any zero fill pages.
157			 */
158			for (; va < eva; va += PAGE_SIZE)
159				if (pmap_kextract(va) == 0)
160					return (EFAULT);
161
162			prot = (uio->uio_rw == UIO_READ) ? VM_PROT_READ :
163			    VM_PROT_WRITE;
164			va = uio->uio_offset;
165			if (va < VM_MIN_DIRECT_ADDRESS &&
166			    kernacc((void *)va, iov->iov_len, prot) == FALSE)
167				return (EFAULT);
168
169			error = uiomove((void *)va, iov->iov_len, uio);
170			break;
171		}
172		/* else panic! */
173	}
174	if (ova != 0)
175		kva_free(ova, PAGE_SIZE * colors);
176	return (error);
177}
178