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/*
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* mmap support for qemu
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*
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* Copyright (c) 2003 Fabrice Bellard
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <http://www.gnu.org/licenses/>.
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*/
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#include <stdlib.h> |
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#include <stdio.h> |
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#include <stdarg.h> |
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#include <string.h> |
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#include <unistd.h> |
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#include <errno.h> |
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#include <sys/types.h> |
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#include <sys/stat.h> |
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#include <sys/mman.h> |
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#include <linux/mman.h> |
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#include <linux/unistd.h> |
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#include "qemu.h" |
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#include "qemu-common.h" |
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//#define DEBUG_MMAP
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#if defined(CONFIG_USE_NPTL)
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static pthread_mutex_t mmap_mutex = PTHREAD_MUTEX_INITIALIZER;
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static __thread int mmap_lock_count; |
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void mmap_lock(void) |
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{ |
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if (mmap_lock_count++ == 0) { |
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pthread_mutex_lock(&mmap_mutex); |
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} |
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} |
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|
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void mmap_unlock(void) |
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{ |
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if (--mmap_lock_count == 0) { |
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pthread_mutex_unlock(&mmap_mutex); |
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} |
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} |
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/* Grab lock to make sure things are in a consistent state after fork(). */
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void mmap_fork_start(void) |
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{ |
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if (mmap_lock_count)
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abort(); |
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pthread_mutex_lock(&mmap_mutex); |
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} |
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|
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void mmap_fork_end(int child) |
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{ |
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if (child)
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pthread_mutex_init(&mmap_mutex, NULL);
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else
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pthread_mutex_unlock(&mmap_mutex); |
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} |
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#else
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/* We aren't threadsafe to start with, so no need to worry about locking. */
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void mmap_lock(void) |
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{ |
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} |
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void mmap_unlock(void) |
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{ |
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} |
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#endif
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|
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/* NOTE: all the constants are the HOST ones, but addresses are target. */
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int target_mprotect(abi_ulong start, abi_ulong len, int prot) |
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{ |
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abi_ulong end, host_start, host_end, addr; |
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int prot1, ret;
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|
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#ifdef DEBUG_MMAP
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printf("mprotect: start=0x" TARGET_ABI_FMT_lx
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"len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c\n", start, len, |
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prot & PROT_READ ? 'r' : '-', |
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prot & PROT_WRITE ? 'w' : '-', |
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prot & PROT_EXEC ? 'x' : '-'); |
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#endif
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|
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if ((start & ~TARGET_PAGE_MASK) != 0) |
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return -EINVAL;
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len = TARGET_PAGE_ALIGN(len); |
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end = start + len; |
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if (end < start)
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return -EINVAL;
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prot &= PROT_READ | PROT_WRITE | PROT_EXEC; |
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if (len == 0) |
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return 0; |
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|
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mmap_lock(); |
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host_start = start & qemu_host_page_mask; |
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host_end = HOST_PAGE_ALIGN(end); |
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if (start > host_start) {
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/* handle host page containing start */
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prot1 = prot; |
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for(addr = host_start; addr < start; addr += TARGET_PAGE_SIZE) {
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prot1 |= page_get_flags(addr); |
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} |
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if (host_end == host_start + qemu_host_page_size) {
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for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
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prot1 |= page_get_flags(addr); |
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} |
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end = host_end; |
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} |
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ret = mprotect(g2h(host_start), qemu_host_page_size, prot1 & PAGE_BITS); |
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if (ret != 0) |
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goto error;
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host_start += qemu_host_page_size; |
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} |
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if (end < host_end) {
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prot1 = prot; |
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for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
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prot1 |= page_get_flags(addr); |
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} |
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ret = mprotect(g2h(host_end - qemu_host_page_size), qemu_host_page_size, |
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prot1 & PAGE_BITS); |
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if (ret != 0) |
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goto error;
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host_end -= qemu_host_page_size; |
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} |
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|
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/* handle the pages in the middle */
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if (host_start < host_end) {
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ret = mprotect(g2h(host_start), host_end - host_start, prot); |
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if (ret != 0) |
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goto error;
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} |
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page_set_flags(start, start + len, prot | PAGE_VALID); |
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mmap_unlock(); |
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return 0; |
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error:
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mmap_unlock(); |
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return ret;
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} |
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|
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/* map an incomplete host page */
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static int mmap_frag(abi_ulong real_start, |
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abi_ulong start, abi_ulong end, |
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int prot, int flags, int fd, abi_ulong offset) |
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{ |
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abi_ulong real_end, addr; |
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void *host_start;
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int prot1, prot_new;
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real_end = real_start + qemu_host_page_size; |
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host_start = g2h(real_start); |
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|
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/* get the protection of the target pages outside the mapping */
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prot1 = 0;
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for(addr = real_start; addr < real_end; addr++) {
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if (addr < start || addr >= end)
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prot1 |= page_get_flags(addr); |
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} |
168 |
|
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if (prot1 == 0) { |
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/* no page was there, so we allocate one */
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void *p = mmap(host_start, qemu_host_page_size, prot,
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flags | MAP_ANONYMOUS, -1, 0); |
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if (p == MAP_FAILED)
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return -1; |
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prot1 = prot; |
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} |
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prot1 &= PAGE_BITS; |
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prot_new = prot | prot1; |
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if (!(flags & MAP_ANONYMOUS)) {
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/* msync() won't work here, so we return an error if write is
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possible while it is a shared mapping */
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if ((flags & MAP_TYPE) == MAP_SHARED &&
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(prot & PROT_WRITE)) |
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return -1; |
186 |
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/* adjust protection to be able to read */
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if (!(prot1 & PROT_WRITE))
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mprotect(host_start, qemu_host_page_size, prot1 | PROT_WRITE); |
190 |
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/* read the corresponding file data */
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if (pread(fd, g2h(start), end - start, offset) == -1) |
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return -1; |
194 |
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/* put final protection */
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if (prot_new != (prot1 | PROT_WRITE))
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mprotect(host_start, qemu_host_page_size, prot_new); |
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} else {
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/* just update the protection */
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if (prot_new != prot1) {
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mprotect(host_start, qemu_host_page_size, prot_new); |
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} |
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} |
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return 0; |
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} |
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#if HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 64 |
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# define TASK_UNMAPPED_BASE (1ul << 38) |
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#elif defined(__CYGWIN__)
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/* Cygwin doesn't have a whole lot of address space. */
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# define TASK_UNMAPPED_BASE 0x18000000 |
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#else
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# define TASK_UNMAPPED_BASE 0x40000000 |
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#endif
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static abi_ulong mmap_next_start = TASK_UNMAPPED_BASE;
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unsigned long last_brk; |
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#ifdef CONFIG_USE_GUEST_BASE
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/* Subroutine of mmap_find_vma, used when we have pre-allocated a chunk
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of guest address space. */
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static abi_ulong mmap_find_vma_reserved(abi_ulong start, abi_ulong size)
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{ |
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abi_ulong addr; |
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abi_ulong last_addr; |
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int prot;
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int looped = 0; |
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if (size > RESERVED_VA) {
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return (abi_ulong)-1; |
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} |
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last_addr = start; |
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for (addr = start; last_addr + size != addr; addr += qemu_host_page_size) {
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if (last_addr + size >= RESERVED_VA
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|| (abi_ulong)(last_addr + size) < last_addr) { |
237 |
if (looped) {
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return (abi_ulong)-1; |
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} |
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last_addr = qemu_host_page_size; |
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addr = 0;
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looped = 1;
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continue;
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} |
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prot = page_get_flags(addr); |
246 |
if (prot) {
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last_addr = addr + qemu_host_page_size; |
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} |
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} |
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mmap_next_start = addr; |
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return last_addr;
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} |
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#endif
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/*
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* Find and reserve a free memory area of size 'size'. The search
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* starts at 'start'.
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* It must be called with mmap_lock() held.
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* Return -1 if error.
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*/
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abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size) |
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{ |
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void *ptr, *prev;
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abi_ulong addr; |
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int wrapped, repeat;
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/* If 'start' == 0, then a default start address is used. */
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if (start == 0) { |
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start = mmap_next_start; |
270 |
} else {
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start &= qemu_host_page_mask; |
272 |
} |
273 |
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size = HOST_PAGE_ALIGN(size); |
275 |
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#ifdef CONFIG_USE_GUEST_BASE
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if (RESERVED_VA) {
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return mmap_find_vma_reserved(start, size);
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} |
280 |
#endif
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addr = start; |
283 |
wrapped = repeat = 0;
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prev = 0;
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for (;; prev = ptr) {
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/*
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* Reserve needed memory area to avoid a race.
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* It should be discarded using:
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* - mmap() with MAP_FIXED flag
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* - mremap() with MREMAP_FIXED flag
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* - shmat() with SHM_REMAP flag
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*/
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ptr = mmap(g2h(addr), size, PROT_NONE, |
295 |
MAP_ANONYMOUS|MAP_PRIVATE|MAP_NORESERVE, -1, 0); |
296 |
|
297 |
/* ENOMEM, if host address space has no memory */
|
298 |
if (ptr == MAP_FAILED) {
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299 |
return (abi_ulong)-1; |
300 |
} |
301 |
|
302 |
/* Count the number of sequential returns of the same address.
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303 |
This is used to modify the search algorithm below. */
|
304 |
repeat = (ptr == prev ? repeat + 1 : 0); |
305 |
|
306 |
if (h2g_valid(ptr + size - 1)) { |
307 |
addr = h2g(ptr); |
308 |
|
309 |
if ((addr & ~TARGET_PAGE_MASK) == 0) { |
310 |
/* Success. */
|
311 |
if (start == mmap_next_start && addr >= TASK_UNMAPPED_BASE) {
|
312 |
mmap_next_start = addr + size; |
313 |
} |
314 |
return addr;
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315 |
} |
316 |
|
317 |
/* The address is not properly aligned for the target. */
|
318 |
switch (repeat) {
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319 |
case 0: |
320 |
/* Assume the result that the kernel gave us is the
|
321 |
first with enough free space, so start again at the
|
322 |
next higher target page. */
|
323 |
addr = TARGET_PAGE_ALIGN(addr); |
324 |
break;
|
325 |
case 1: |
326 |
/* Sometimes the kernel decides to perform the allocation
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327 |
at the top end of memory instead. */
|
328 |
addr &= TARGET_PAGE_MASK; |
329 |
break;
|
330 |
case 2: |
331 |
/* Start over at low memory. */
|
332 |
addr = 0;
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333 |
break;
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334 |
default:
|
335 |
/* Fail. This unaligned block must the last. */
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336 |
addr = -1;
|
337 |
break;
|
338 |
} |
339 |
} else {
|
340 |
/* Since the result the kernel gave didn't fit, start
|
341 |
again at low memory. If any repetition, fail. */
|
342 |
addr = (repeat ? -1 : 0); |
343 |
} |
344 |
|
345 |
/* Unmap and try again. */
|
346 |
munmap(ptr, size); |
347 |
|
348 |
/* ENOMEM if we checked the whole of the target address space. */
|
349 |
if (addr == (abi_ulong)-1) { |
350 |
return (abi_ulong)-1; |
351 |
} else if (addr == 0) { |
352 |
if (wrapped) {
|
353 |
return (abi_ulong)-1; |
354 |
} |
355 |
wrapped = 1;
|
356 |
/* Don't actually use 0 when wrapping, instead indicate
|
357 |
that we'd truely like an allocation in low memory. */
|
358 |
addr = (mmap_min_addr > TARGET_PAGE_SIZE |
359 |
? TARGET_PAGE_ALIGN(mmap_min_addr) |
360 |
: TARGET_PAGE_SIZE); |
361 |
} else if (wrapped && addr >= start) { |
362 |
return (abi_ulong)-1; |
363 |
} |
364 |
} |
365 |
} |
366 |
|
367 |
/* NOTE: all the constants are the HOST ones */
|
368 |
abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
|
369 |
int flags, int fd, abi_ulong offset) |
370 |
{ |
371 |
abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len; |
372 |
unsigned long host_start; |
373 |
|
374 |
mmap_lock(); |
375 |
#ifdef DEBUG_MMAP
|
376 |
{ |
377 |
printf("mmap: start=0x" TARGET_ABI_FMT_lx
|
378 |
" len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c flags=", |
379 |
start, len, |
380 |
prot & PROT_READ ? 'r' : '-', |
381 |
prot & PROT_WRITE ? 'w' : '-', |
382 |
prot & PROT_EXEC ? 'x' : '-'); |
383 |
if (flags & MAP_FIXED)
|
384 |
printf("MAP_FIXED ");
|
385 |
if (flags & MAP_ANONYMOUS)
|
386 |
printf("MAP_ANON ");
|
387 |
switch(flags & MAP_TYPE) {
|
388 |
case MAP_PRIVATE:
|
389 |
printf("MAP_PRIVATE ");
|
390 |
break;
|
391 |
case MAP_SHARED:
|
392 |
printf("MAP_SHARED ");
|
393 |
break;
|
394 |
default:
|
395 |
printf("[MAP_TYPE=0x%x] ", flags & MAP_TYPE);
|
396 |
break;
|
397 |
} |
398 |
printf("fd=%d offset=" TARGET_ABI_FMT_lx "\n", fd, offset); |
399 |
} |
400 |
#endif
|
401 |
|
402 |
if (offset & ~TARGET_PAGE_MASK) {
|
403 |
errno = EINVAL; |
404 |
goto fail;
|
405 |
} |
406 |
|
407 |
len = TARGET_PAGE_ALIGN(len); |
408 |
if (len == 0) |
409 |
goto the_end;
|
410 |
real_start = start & qemu_host_page_mask; |
411 |
|
412 |
/* When mapping files into a memory area larger than the file, accesses
|
413 |
to pages beyond the file size will cause a SIGBUS.
|
414 |
|
415 |
For example, if mmaping a file of 100 bytes on a host with 4K pages
|
416 |
emulating a target with 8K pages, the target expects to be able to
|
417 |
access the first 8K. But the host will trap us on any access beyond
|
418 |
4K.
|
419 |
|
420 |
When emulating a target with a larger page-size than the hosts, we
|
421 |
may need to truncate file maps at EOF and add extra anonymous pages
|
422 |
up to the targets page boundary. */
|
423 |
|
424 |
if ((qemu_real_host_page_size < TARGET_PAGE_SIZE)
|
425 |
&& !(flags & MAP_ANONYMOUS)) { |
426 |
struct stat sb;
|
427 |
|
428 |
if (fstat (fd, &sb) == -1) |
429 |
goto fail;
|
430 |
|
431 |
/* Are we trying to create a map beyond EOF?. */
|
432 |
if (offset + len > sb.st_size) {
|
433 |
/* If so, truncate the file map at eof aligned with
|
434 |
the hosts real pagesize. Additional anonymous maps
|
435 |
will be created beyond EOF. */
|
436 |
len = (sb.st_size - offset); |
437 |
len += qemu_real_host_page_size - 1;
|
438 |
len &= ~(qemu_real_host_page_size - 1);
|
439 |
} |
440 |
} |
441 |
|
442 |
if (!(flags & MAP_FIXED)) {
|
443 |
abi_ulong mmap_start; |
444 |
void *p;
|
445 |
host_offset = offset & qemu_host_page_mask; |
446 |
host_len = len + offset - host_offset; |
447 |
host_len = HOST_PAGE_ALIGN(host_len); |
448 |
mmap_start = mmap_find_vma(real_start, host_len); |
449 |
if (mmap_start == (abi_ulong)-1) { |
450 |
errno = ENOMEM; |
451 |
goto fail;
|
452 |
} |
453 |
/* Note: we prefer to control the mapping address. It is
|
454 |
especially important if qemu_host_page_size >
|
455 |
qemu_real_host_page_size */
|
456 |
p = mmap(g2h(mmap_start), |
457 |
host_len, prot, flags | MAP_FIXED | MAP_ANONYMOUS, -1, 0); |
458 |
if (p == MAP_FAILED)
|
459 |
goto fail;
|
460 |
/* update start so that it points to the file position at 'offset' */
|
461 |
host_start = (unsigned long)p; |
462 |
if (!(flags & MAP_ANONYMOUS)) {
|
463 |
p = mmap(g2h(mmap_start), len, prot, |
464 |
flags | MAP_FIXED, fd, host_offset); |
465 |
host_start += offset - host_offset; |
466 |
} |
467 |
start = h2g(host_start); |
468 |
} else {
|
469 |
if (start & ~TARGET_PAGE_MASK) {
|
470 |
errno = EINVAL; |
471 |
goto fail;
|
472 |
} |
473 |
end = start + len; |
474 |
real_end = HOST_PAGE_ALIGN(end); |
475 |
|
476 |
/*
|
477 |
* Test if requested memory area fits target address space
|
478 |
* It can fail only on 64-bit host with 32-bit target.
|
479 |
* On any other target/host host mmap() handles this error correctly.
|
480 |
*/
|
481 |
if ((unsigned long)start + len - 1 > (abi_ulong) -1) { |
482 |
errno = EINVAL; |
483 |
goto fail;
|
484 |
} |
485 |
|
486 |
/* worst case: we cannot map the file because the offset is not
|
487 |
aligned, so we read it */
|
488 |
if (!(flags & MAP_ANONYMOUS) &&
|
489 |
(offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) { |
490 |
/* msync() won't work here, so we return an error if write is
|
491 |
possible while it is a shared mapping */
|
492 |
if ((flags & MAP_TYPE) == MAP_SHARED &&
|
493 |
(prot & PROT_WRITE)) { |
494 |
errno = EINVAL; |
495 |
goto fail;
|
496 |
} |
497 |
retaddr = target_mmap(start, len, prot | PROT_WRITE, |
498 |
MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, |
499 |
-1, 0); |
500 |
if (retaddr == -1) |
501 |
goto fail;
|
502 |
if (pread(fd, g2h(start), len, offset) == -1) |
503 |
goto fail;
|
504 |
if (!(prot & PROT_WRITE)) {
|
505 |
ret = target_mprotect(start, len, prot); |
506 |
if (ret != 0) { |
507 |
start = ret; |
508 |
goto the_end;
|
509 |
} |
510 |
} |
511 |
goto the_end;
|
512 |
} |
513 |
|
514 |
/* handle the start of the mapping */
|
515 |
if (start > real_start) {
|
516 |
if (real_end == real_start + qemu_host_page_size) {
|
517 |
/* one single host page */
|
518 |
ret = mmap_frag(real_start, start, end, |
519 |
prot, flags, fd, offset); |
520 |
if (ret == -1) |
521 |
goto fail;
|
522 |
goto the_end1;
|
523 |
} |
524 |
ret = mmap_frag(real_start, start, real_start + qemu_host_page_size, |
525 |
prot, flags, fd, offset); |
526 |
if (ret == -1) |
527 |
goto fail;
|
528 |
real_start += qemu_host_page_size; |
529 |
} |
530 |
/* handle the end of the mapping */
|
531 |
if (end < real_end) {
|
532 |
ret = mmap_frag(real_end - qemu_host_page_size, |
533 |
real_end - qemu_host_page_size, real_end, |
534 |
prot, flags, fd, |
535 |
offset + real_end - qemu_host_page_size - start); |
536 |
if (ret == -1) |
537 |
goto fail;
|
538 |
real_end -= qemu_host_page_size; |
539 |
} |
540 |
|
541 |
/* map the middle (easier) */
|
542 |
if (real_start < real_end) {
|
543 |
void *p;
|
544 |
unsigned long offset1; |
545 |
if (flags & MAP_ANONYMOUS)
|
546 |
offset1 = 0;
|
547 |
else
|
548 |
offset1 = offset + real_start - start; |
549 |
p = mmap(g2h(real_start), real_end - real_start, |
550 |
prot, flags, fd, offset1); |
551 |
if (p == MAP_FAILED)
|
552 |
goto fail;
|
553 |
} |
554 |
} |
555 |
the_end1:
|
556 |
page_set_flags(start, start + len, prot | PAGE_VALID); |
557 |
the_end:
|
558 |
#ifdef DEBUG_MMAP
|
559 |
printf("ret=0x" TARGET_ABI_FMT_lx "\n", start); |
560 |
page_dump(stdout); |
561 |
printf("\n");
|
562 |
#endif
|
563 |
mmap_unlock(); |
564 |
return start;
|
565 |
fail:
|
566 |
mmap_unlock(); |
567 |
return -1; |
568 |
} |
569 |
|
570 |
static void mmap_reserve(abi_ulong start, abi_ulong size) |
571 |
{ |
572 |
abi_ulong real_start; |
573 |
abi_ulong real_end; |
574 |
abi_ulong addr; |
575 |
abi_ulong end; |
576 |
int prot;
|
577 |
|
578 |
real_start = start & qemu_host_page_mask; |
579 |
real_end = HOST_PAGE_ALIGN(start + size); |
580 |
end = start + size; |
581 |
if (start > real_start) {
|
582 |
/* handle host page containing start */
|
583 |
prot = 0;
|
584 |
for (addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) {
|
585 |
prot |= page_get_flags(addr); |
586 |
} |
587 |
if (real_end == real_start + qemu_host_page_size) {
|
588 |
for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
|
589 |
prot |= page_get_flags(addr); |
590 |
} |
591 |
end = real_end; |
592 |
} |
593 |
if (prot != 0) |
594 |
real_start += qemu_host_page_size; |
595 |
} |
596 |
if (end < real_end) {
|
597 |
prot = 0;
|
598 |
for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
|
599 |
prot |= page_get_flags(addr); |
600 |
} |
601 |
if (prot != 0) |
602 |
real_end -= qemu_host_page_size; |
603 |
} |
604 |
if (real_start != real_end) {
|
605 |
mmap(g2h(real_start), real_end - real_start, PROT_NONE, |
606 |
MAP_FIXED | MAP_ANONYMOUS | MAP_PRIVATE | MAP_NORESERVE, |
607 |
-1, 0); |
608 |
} |
609 |
} |
610 |
|
611 |
int target_munmap(abi_ulong start, abi_ulong len)
|
612 |
{ |
613 |
abi_ulong end, real_start, real_end, addr; |
614 |
int prot, ret;
|
615 |
|
616 |
#ifdef DEBUG_MMAP
|
617 |
printf("munmap: start=0x" TARGET_ABI_FMT_lx " len=0x" |
618 |
TARGET_ABI_FMT_lx "\n",
|
619 |
start, len); |
620 |
#endif
|
621 |
if (start & ~TARGET_PAGE_MASK)
|
622 |
return -EINVAL;
|
623 |
len = TARGET_PAGE_ALIGN(len); |
624 |
if (len == 0) |
625 |
return -EINVAL;
|
626 |
mmap_lock(); |
627 |
end = start + len; |
628 |
real_start = start & qemu_host_page_mask; |
629 |
real_end = HOST_PAGE_ALIGN(end); |
630 |
|
631 |
if (start > real_start) {
|
632 |
/* handle host page containing start */
|
633 |
prot = 0;
|
634 |
for(addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) {
|
635 |
prot |= page_get_flags(addr); |
636 |
} |
637 |
if (real_end == real_start + qemu_host_page_size) {
|
638 |
for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
|
639 |
prot |= page_get_flags(addr); |
640 |
} |
641 |
end = real_end; |
642 |
} |
643 |
if (prot != 0) |
644 |
real_start += qemu_host_page_size; |
645 |
} |
646 |
if (end < real_end) {
|
647 |
prot = 0;
|
648 |
for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
|
649 |
prot |= page_get_flags(addr); |
650 |
} |
651 |
if (prot != 0) |
652 |
real_end -= qemu_host_page_size; |
653 |
} |
654 |
|
655 |
ret = 0;
|
656 |
/* unmap what we can */
|
657 |
if (real_start < real_end) {
|
658 |
if (RESERVED_VA) {
|
659 |
mmap_reserve(real_start, real_end - real_start); |
660 |
} else {
|
661 |
ret = munmap(g2h(real_start), real_end - real_start); |
662 |
} |
663 |
} |
664 |
|
665 |
if (ret == 0) |
666 |
page_set_flags(start, start + len, 0);
|
667 |
mmap_unlock(); |
668 |
return ret;
|
669 |
} |
670 |
|
671 |
abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size, |
672 |
abi_ulong new_size, unsigned long flags, |
673 |
abi_ulong new_addr) |
674 |
{ |
675 |
int prot;
|
676 |
void *host_addr;
|
677 |
|
678 |
mmap_lock(); |
679 |
|
680 |
if (flags & MREMAP_FIXED) {
|
681 |
host_addr = (void *) syscall(__NR_mremap, g2h(old_addr),
|
682 |
old_size, new_size, |
683 |
flags, |
684 |
g2h(new_addr)); |
685 |
|
686 |
if (RESERVED_VA && host_addr != MAP_FAILED) {
|
687 |
/* If new and old addresses overlap then the above mremap will
|
688 |
already have failed with EINVAL. */
|
689 |
mmap_reserve(old_addr, old_size); |
690 |
} |
691 |
} else if (flags & MREMAP_MAYMOVE) { |
692 |
abi_ulong mmap_start; |
693 |
|
694 |
mmap_start = mmap_find_vma(0, new_size);
|
695 |
|
696 |
if (mmap_start == -1) { |
697 |
errno = ENOMEM; |
698 |
host_addr = MAP_FAILED; |
699 |
} else {
|
700 |
host_addr = (void *) syscall(__NR_mremap, g2h(old_addr),
|
701 |
old_size, new_size, |
702 |
flags | MREMAP_FIXED, |
703 |
g2h(mmap_start)); |
704 |
if ( RESERVED_VA ) {
|
705 |
mmap_reserve(old_addr, old_size); |
706 |
} |
707 |
} |
708 |
} else {
|
709 |
int prot = 0; |
710 |
if (RESERVED_VA && old_size < new_size) {
|
711 |
abi_ulong addr; |
712 |
for (addr = old_addr + old_size;
|
713 |
addr < old_addr + new_size; |
714 |
addr++) { |
715 |
prot |= page_get_flags(addr); |
716 |
} |
717 |
} |
718 |
if (prot == 0) { |
719 |
host_addr = mremap(g2h(old_addr), old_size, new_size, flags); |
720 |
if (host_addr != MAP_FAILED && RESERVED_VA && old_size > new_size) {
|
721 |
mmap_reserve(old_addr + old_size, new_size - old_size); |
722 |
} |
723 |
} else {
|
724 |
errno = ENOMEM; |
725 |
host_addr = MAP_FAILED; |
726 |
} |
727 |
/* Check if address fits target address space */
|
728 |
if ((unsigned long)host_addr + new_size > (abi_ulong)-1) { |
729 |
/* Revert mremap() changes */
|
730 |
host_addr = mremap(g2h(old_addr), new_size, old_size, flags); |
731 |
errno = ENOMEM; |
732 |
host_addr = MAP_FAILED; |
733 |
} |
734 |
} |
735 |
|
736 |
if (host_addr == MAP_FAILED) {
|
737 |
new_addr = -1;
|
738 |
} else {
|
739 |
new_addr = h2g(host_addr); |
740 |
prot = page_get_flags(old_addr); |
741 |
page_set_flags(old_addr, old_addr + old_size, 0);
|
742 |
page_set_flags(new_addr, new_addr + new_size, prot | PAGE_VALID); |
743 |
} |
744 |
mmap_unlock(); |
745 |
return new_addr;
|
746 |
} |
747 |
|
748 |
int target_msync(abi_ulong start, abi_ulong len, int flags) |
749 |
{ |
750 |
abi_ulong end; |
751 |
|
752 |
if (start & ~TARGET_PAGE_MASK)
|
753 |
return -EINVAL;
|
754 |
len = TARGET_PAGE_ALIGN(len); |
755 |
end = start + len; |
756 |
if (end < start)
|
757 |
return -EINVAL;
|
758 |
if (end == start)
|
759 |
return 0; |
760 |
|
761 |
start &= qemu_host_page_mask; |
762 |
return msync(g2h(start), end - start, flags);
|
763 |
} |