Loading...
--- xnu/xnu-12377.101.15/bsd/dev/mem.c
+++ /dev/null
@@ -1,313 +0,0 @@
-/*
- * Copyright (c) 2000-2016 Apple Inc. All rights reserved.
- *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. The rights granted to you under the License
- * may not be used to create, or enable the creation or redistribution of,
- * unlawful or unlicensed copies of an Apple operating system, or to
- * circumvent, violate, or enable the circumvention or violation of, any
- * terms of an Apple operating system software license agreement.
- *
- * Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
- */
-/*-
- * Copyright (c) 1988 University of Utah.
- * Copyright (c) 1982, 1986, 1990, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * the Systems Programming Group of the University of Utah Computer
- * Science Department, and code derived from software contributed to
- * Berkeley by William Jolitz.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * from: Utah $Hdr: mem.c 1.13 89/10/08$
- * @(#)mem.c 8.1 (Berkeley) 6/11/93
- */
-
-/*
- * Memory special file
- */
-
-#include <sys/param.h>
-#include <sys/dir.h>
-#include <sys/proc.h>
-#include <sys/systm.h>
-#include <sys/conf.h>
-#include <sys/vm.h>
-#include <sys/uio_internal.h>
-
-#include <kern/zalloc.h>
-
-#include <mach/vm_types.h>
-#include <mach/vm_param.h>
-#include <vm/vm_kern.h> /* for kernel_map */
-#include <libkern/section_keywords.h>
-
-#include <pexpert/pexpert.h> /* for PE_parse_boot_argn */
-
-boolean_t iskmemdev(dev_t dev);
-
-#if CONFIG_DEV_KMEM
-boolean_t dev_kmem_enabled;
-boolean_t dev_kmem_mask_top_bit;
-
-void dev_kmem_init(void);
-
-#if defined(__x86_64__)
-extern addr64_t kvtophys(vm_offset_t va);
-#else
-#error need kvtophys prototype
-#endif
-extern boolean_t kernacc(off_t, size_t );
-
-#endif
-
-static SECURITY_READ_ONLY_LATE(caddr_t) devzerobuf;
-
-int mmread(dev_t dev, struct uio *uio);
-int mmwrite(dev_t dev, struct uio *uio);
-int mmioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p);
-int mmrw(dev_t dev, struct uio *uio, enum uio_rw rw);
-
-int
-mmread(dev_t dev, struct uio *uio)
-{
- return mmrw(dev, uio, UIO_READ);
-}
-
-int
-mmwrite(dev_t dev, struct uio *uio)
-{
- return mmrw(dev, uio, UIO_WRITE);
-}
-
-int
-mmioctl(dev_t dev, u_long cmd, __unused caddr_t data,
- __unused int flag, __unused struct proc *p)
-{
- int minnum = minor(dev);
-
- if (0 == minnum || 1 == minnum) {
- /* /dev/mem and /dev/kmem */
-#if CONFIG_DEV_KMEM
- if (!dev_kmem_enabled) {
- return ENODEV;
- }
-#else
- return ENODEV;
-#endif
- }
-
- switch (cmd) {
- case FIONBIO:
- case FIOASYNC:
- /* OK to do nothing: we always return immediately */
- break;
- default:
- return ENODEV;
- }
-
- return 0;
-}
-
-int
-mmrw(dev_t dev, struct uio *uio, enum uio_rw rw)
-{
- user_size_t c;
- int error = 0;
-
- while (uio_resid(uio) > 0) {
- uio_update(uio, 0);
-
- switch (minor(dev)) {
- /* minor device 0 is physical memory */
- case 0:
- return ENODEV;
-
- /* minor device 1 is kernel memory */
- case 1:
-#if !CONFIG_DEV_KMEM
- return ENODEV;
-#else /* CONFIG_DEV_KMEM */
- if (!dev_kmem_enabled) {
- return ENODEV;
- }
-
- vm_address_t kaddr = (vm_address_t)uio->uio_offset;
- if (dev_kmem_mask_top_bit) {
- /*
- * KVA addresses of the form 0xFFFFFF80AABBCCDD can't be
- * represented as a signed off_t correctly. In these cases,
- * 0x7FFFFF80AABBCCDD is passed in, and the top bit OR-ed
- * on.
- */
- const vm_address_t top_bit = (~((vm_address_t)0)) ^ (~((vm_address_t)0) >> 1UL);
- if (kaddr & top_bit) {
- /* top bit should not be set already */
- return EFAULT;
- }
- kaddr |= top_bit;
- }
-
- c = uio_curriovlen(uio);
-
- /* Do some sanity checking */
- if ((kaddr > (VM_MAX_KERNEL_ADDRESS - c)) ||
- (kaddr <= VM_MIN_KERNEL_AND_KEXT_ADDRESS)) {
- goto fault;
- }
- if (!kernacc(kaddr, c)) {
- goto fault;
- }
- error = uiomove((const char *)(uintptr_t)kaddr,
- (int)c, uio);
- if (error) {
- break;
- }
-
- continue; /* Keep going until UIO is done */
-#endif /* CONFIG_DEV_KMEM */
-
- /* minor device 2 is EOF/RATHOLE */
- case 2:
- if (rw == UIO_READ) {
- return 0;
- }
- c = uio_curriovlen(uio);
-
- error = 0; /* Always succeeds, always consumes all input */
- break;
- case 3:
- assert(devzerobuf != NULL);
-
- if (uio->uio_rw == UIO_WRITE) {
- c = uio_curriovlen(uio);
-
- error = 0; /* Always succeeds, always consumes all input */
- break;
- }
-
- c = MIN(uio_curriovlen(uio), PAGE_SIZE);
- error = uiomove(devzerobuf, (int)c, uio);
- if (error) {
- break;
- }
-
- continue; /* Keep going until UIO is done */
- default:
- return ENODEV;
- }
-
- if (error) {
- break;
- }
-
- uio_update(uio, c);
- }
- return error;
-#if CONFIG_DEV_KMEM
-fault:
- return EFAULT;
-#endif
-}
-
-__startup_func
-static void
-devzerobuf_init(void)
-{
- devzerobuf = zalloc_permanent(PAGE_SIZE, ZALIGN_NONE); /* zeroed */
-}
-STARTUP(ZALLOC, STARTUP_RANK_LAST, devzerobuf_init);
-
-#if CONFIG_DEV_KMEM
-void
-dev_kmem_init(void)
-{
- uint32_t kmem;
-
- if (PE_i_can_has_debugger(NULL) &&
- PE_parse_boot_argn("kmem", &kmem, sizeof(kmem))) {
- if (kmem & 0x1) {
- dev_kmem_enabled = TRUE;
- }
- if (kmem & 0x2) {
- dev_kmem_mask_top_bit = TRUE;
- }
- }
-}
-
-boolean_t
-kernacc(
- off_t start,
- size_t len
- )
-{
- off_t base;
- off_t end;
-
- base = trunc_page(start);
- end = start + len;
-
- while (base < end) {
- if (kvtophys((vm_offset_t)base) == 0ULL) {
- return FALSE;
- }
- base += page_size;
- }
-
- return TRUE;
-}
-
-#endif /* CONFIG_DEV_KMEM */
-
-/*
- * Returns true if dev is /dev/mem or /dev/kmem.
- */
-boolean_t
-iskmemdev(dev_t dev)
-{
- return major(dev) == 3 && minor(dev) < 2;
-}