2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1988 University of Utah.
5 * Copyright (c) 1982, 1986, 1990 The Regents of the University of California.
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.
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
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.
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
37 * from: Utah $Hdr: mem.c 1.13 89/10/08$
38 * from: @(#)mem.c 7.2 (Berkeley) 5/9/91
39 * from: FreeBSD: src/sys/i386/i386/mem.c,v 1.94 2001/09/26
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
48 * NOTE: other architectures support mmap()'ing the mem device; this
49 * might cause illegal aliases to be created for the locked kernel page(s), so
50 * it is not implemented.
53 #include <sys/param.h>
55 #include <sys/fcntl.h>
56 #include <sys/kernel.h>
58 #include <sys/malloc.h>
59 #include <sys/memrange.h>
60 #include <sys/module.h>
61 #include <sys/mutex.h>
63 #include <sys/signalvar.h>
64 #include <sys/systm.h>
66 #include <sys/vmmeter.h>
69 #include <vm/vm_param.h>
70 #include <vm/vm_page.h>
71 #include <vm/vm_phys.h>
72 #include <vm/vm_kern.h>
74 #include <vm/vm_extern.h>
76 #include <machine/cache.h>
77 #include <machine/md_var.h>
78 #include <machine/tlb.h>
80 #include <machine/memdev.h>
82 struct mem_range_softc mem_range_softc;
86 memrw(struct cdev *dev, struct uio *uio, int flags)
105 while (uio->uio_resid > 0 && error == 0) {
107 if (iov->iov_len == 0) {
110 if (uio->uio_iovcnt < 0)
114 if (dev2unit(dev) == CDEV_MINOR_MEM) {
115 pa = uio->uio_offset & ~PAGE_MASK;
116 if (!is_physical_memory(pa)) {
121 off = uio->uio_offset & PAGE_MASK;
122 cnt = PAGE_SIZE - ((vm_offset_t)iov->iov_base &
124 cnt = ulmin(cnt, PAGE_SIZE - off);
125 cnt = ulmin(cnt, iov->iov_len);
127 m = vm_phys_paddr_to_vm_page(pa);
130 if (dcache_color_ignore == 0)
131 colors = DCACHE_COLORS;
132 ova = kva_alloc(PAGE_SIZE * colors);
138 if (colors != 1 && m->md.color != -1)
139 va = ova + m->md.color * PAGE_SIZE;
142 pmap_qenter(va, &m, 1);
143 error = uiomove((void *)(va + off), cnt,
147 va = TLB_PHYS_TO_DIRECT(pa);
148 error = uiomove((void *)(va + off), cnt,
152 } else if (dev2unit(dev) == CDEV_MINOR_KMEM) {
153 va = trunc_page(uio->uio_offset);
154 eva = round_page(uio->uio_offset + iov->iov_len);
157 * Make sure that all of the pages are currently
158 * resident so we don't create any zero fill pages.
160 for (; va < eva; va += PAGE_SIZE)
161 if (pmap_kextract(va) == 0)
164 prot = (uio->uio_rw == UIO_READ) ? VM_PROT_READ :
166 va = uio->uio_offset;
167 if (va < VM_MIN_DIRECT_ADDRESS &&
168 kernacc((void *)va, iov->iov_len, prot) == FALSE)
171 error = uiomove((void *)va, iov->iov_len, uio);
177 kva_free(ova, PAGE_SIZE * colors);