FCL/sf/adapt/qemu: comparison symbian-qemu-0.9.1-12/qemu-symbian-svp/linux-user/mmap.c

equal deleted inserted replaced

-:ffa851df0825
+:2fb8b9db1c86
+/*
+*  mmap support for qemu
+*
+*  Copyright (c) 2003 Fabrice Bellard
+*
+*  This program is free software; you can redistribute it and/or modify
+*  it under the terms of the GNU General Public License as published by
+*  the Free Software Foundation; either version 2 of the License, or
+*  (at your option) any later version.
+*
+*  This program is distributed in the hope that it will be useful,
+*  but WITHOUT ANY WARRANTY; without even the implied warranty of
+*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*  GNU General Public License for more details.
+*
+*  You should have received a copy of the GNU General Public License
+*  along with this program; if not, write to the Free Software
+*  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/mman.h>
+#include <linux/mman.h>
+#include <linux/unistd.h>
+#include "qemu.h"
+#include "qemu-common.h"
+//#define DEBUG_MMAP
+#if defined(USE_NPTL)
+pthread_mutex_t mmap_mutex;
+static int __thread mmap_lock_count;
+void mmap_lock(void)
+{
+if (mmap_lock_count++ == 0) {
+pthread_mutex_lock(&mmap_mutex);
+}
+}
+void mmap_unlock(void)
+{
+if (--mmap_lock_count == 0) {
+pthread_mutex_unlock(&mmap_mutex);
+}
+}
+/* Grab lock to make sure things are in a consistent state after fork().  */
+void mmap_fork_start(void)
+{
+if (mmap_lock_count)
+abort();
+pthread_mutex_lock(&mmap_mutex);
+}
+void mmap_fork_end(int child)
+{
+if (child)
+pthread_mutex_init(&mmap_mutex, NULL);
+else
+pthread_mutex_unlock(&mmap_mutex);
+}
+#else
+/* We aren't threadsafe to start with, so no need to worry about locking.  */
+void mmap_lock(void)
+{
+}
+void mmap_unlock(void)
+{
+}
+#endif
+void *qemu_vmalloc(size_t size)
+{
+void *p;
+unsigned long addr;
+mmap_lock();
+/* Use map and mark the pages as used.  */
+p = mmap(NULL, size, PROT_READ | PROT_WRITE,
+MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+addr = (unsigned long)p;
+if (addr == (target_ulong) addr) {
+/* Allocated region overlaps guest address space.
+This may recurse.  */
+page_set_flags(addr & TARGET_PAGE_MASK, TARGET_PAGE_ALIGN(addr + size),
+PAGE_RESERVED);
+}
+mmap_unlock();
+return p;
+}
+void *qemu_malloc(size_t size)
+{
+char * p;
+size += 16;
+p = qemu_vmalloc(size);
+*(size_t *)p = size;
+return p + 16;
+}
+/* We use map, which is always zero initialized.  */
+void * qemu_mallocz(size_t size)
+{
+return qemu_malloc(size);
+}
+void qemu_free(void *ptr)
+{
+/* FIXME: We should unmark the reserved pages here.  However this gets
+complicated when one target page spans multiple host pages, so we
+don't bother.  */
+size_t *p;
+p = (size_t *)((char *)ptr - 16);
+munmap(p, *p);
+}
+/* NOTE: all the constants are the HOST ones, but addresses are target. */
+int target_mprotect(abi_ulong start, abi_ulong len, int prot)
+{
+abi_ulong end, host_start, host_end, addr;
+int prot1, ret;
+#ifdef DEBUG_MMAP
+printf("mprotect: start=0x" TARGET_FMT_lx
+"len=0x" TARGET_FMT_lx " prot=%c%c%c\n", start, len,
+prot & PROT_READ ? 'r' : '-',
+prot & PROT_WRITE ? 'w' : '-',
+prot & PROT_EXEC ? 'x' : '-');
+#endif
+if ((start & ~TARGET_PAGE_MASK) != 0)
+return -EINVAL;
+len = TARGET_PAGE_ALIGN(len);
+end = start + len;
+if (end < start)
+return -EINVAL;
+prot &= PROT_READ | PROT_WRITE | PROT_EXEC;
+if (len == 0)
+return 0;
+mmap_lock();
+host_start = start & qemu_host_page_mask;
+host_end = HOST_PAGE_ALIGN(end);
+if (start > host_start) {
+/* handle host page containing start */
+prot1 = prot;
+for(addr = host_start; addr < start; addr += TARGET_PAGE_SIZE) {
+prot1 |= page_get_flags(addr);
+}
+if (host_end == host_start + qemu_host_page_size) {
+for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
+prot1 |= page_get_flags(addr);
+}
+end = host_end;
+}
+ret = mprotect(g2h(host_start), qemu_host_page_size, prot1 & PAGE_BITS);
+if (ret != 0)
+goto error;
+host_start += qemu_host_page_size;
+}
+if (end < host_end) {
+prot1 = prot;
+for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
+prot1 |= page_get_flags(addr);
+}
+ret = mprotect(g2h(host_end - qemu_host_page_size), qemu_host_page_size,
+prot1 & PAGE_BITS);
+if (ret != 0)
+goto error;
+host_end -= qemu_host_page_size;
+}
+/* handle the pages in the middle */
+if (host_start < host_end) {
+ret = mprotect(g2h(host_start), host_end - host_start, prot);
+if (ret != 0)
+goto error;
+}
+page_set_flags(start, start + len, prot | PAGE_VALID);
+mmap_unlock();
+return 0;
+error:
+mmap_unlock();
+return ret;
+}
+/* map an incomplete host page */
+static int mmap_frag(abi_ulong real_start,
+abi_ulong start, abi_ulong end,
+int prot, int flags, int fd, abi_ulong offset)
+{
+abi_ulong real_end, addr;
+void *host_start;
+int prot1, prot_new;
+real_end = real_start + qemu_host_page_size;
+host_start = g2h(real_start);
+/* get the protection of the target pages outside the mapping */
+prot1 = 0;
+for(addr = real_start; addr < real_end; addr++) {
+if (addr < start || addr >= end)
+prot1 |= page_get_flags(addr);
+}
+if (prot1 == 0) {
+/* no page was there, so we allocate one */
+void *p = mmap(host_start, qemu_host_page_size, prot,
+flags | MAP_ANONYMOUS, -1, 0);
+if (p == MAP_FAILED)
+return -1;
+prot1 = prot;
+}
+prot1 &= PAGE_BITS;
+prot_new = prot | prot1;
+if (!(flags & MAP_ANONYMOUS)) {
+/* msync() won't work here, so we return an error if write is
+possible while it is a shared mapping */
+if ((flags & MAP_TYPE) == MAP_SHARED &&
+(prot & PROT_WRITE))
+return -EINVAL;
+/* adjust protection to be able to read */
+if (!(prot1 & PROT_WRITE))
+mprotect(host_start, qemu_host_page_size, prot1 | PROT_WRITE);
+/* read the corresponding file data */
+pread(fd, g2h(start), end - start, offset);
+/* put final protection */
+if (prot_new != (prot1 | PROT_WRITE))
+mprotect(host_start, qemu_host_page_size, prot_new);
+} else {
+/* just update the protection */
+if (prot_new != prot1) {
+mprotect(host_start, qemu_host_page_size, prot_new);
+}
+}
+return 0;
+}
+#if defined(__CYGWIN__)
+/* Cygwin doesn't have a whole lot of address space.  */
+static abi_ulong mmap_next_start = 0x18000000;
+#else
+static abi_ulong mmap_next_start = 0x40000000;
+#endif
+unsigned long last_brk;
+/* find a free memory area of size 'size'. The search starts at
+'start'. If 'start' == 0, then a default start address is used.
+Return -1 if error.
+*/
+/* page_init() marks pages used by the host as reserved to be sure not
+to use them. */
+static abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size)
+{
+abi_ulong addr, addr1, addr_start;
+int prot;
+unsigned long new_brk;
+new_brk = (unsigned long)sbrk(0);
+if (last_brk && last_brk < new_brk && last_brk == (target_ulong)last_brk) {
+/* This is a hack to catch the host allocating memory with brk().
+If it uses mmap then we loose.
+FIXME: We really want to avoid the host allocating memory in
+the first place, and maybe leave some slack to avoid switching
+to mmap.  */
+page_set_flags(last_brk & TARGET_PAGE_MASK,
+TARGET_PAGE_ALIGN(new_brk),
+PAGE_RESERVED);
+}
+last_brk = new_brk;
+size = HOST_PAGE_ALIGN(size);
+start = start & qemu_host_page_mask;
+addr = start;
+if (addr == 0)
+addr = mmap_next_start;
+addr_start = addr;
+for(;;) {
+prot = 0;
+for(addr1 = addr; addr1 < (addr + size); addr1 += TARGET_PAGE_SIZE) {
+prot |= page_get_flags(addr1);
+}
+if (prot == 0)
+break;
+addr += qemu_host_page_size;
+/* we found nothing */
+if (addr == addr_start)
+return (abi_ulong)-1;
+}
+if (start == 0)
+mmap_next_start = addr + size;
+return addr;
+}
+/* NOTE: all the constants are the HOST ones */
+abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
+int flags, int fd, abi_ulong offset)
+{
+abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len;
+unsigned long host_start;
+mmap_lock();
+#ifdef DEBUG_MMAP
+{
+printf("mmap: start=0x" TARGET_FMT_lx
+" len=0x" TARGET_FMT_lx " prot=%c%c%c flags=",
+start, len,
+prot & PROT_READ ? 'r' : '-',
+prot & PROT_WRITE ? 'w' : '-',
+prot & PROT_EXEC ? 'x' : '-');
+if (flags & MAP_FIXED)
+printf("MAP_FIXED ");
+if (flags & MAP_ANONYMOUS)
+printf("MAP_ANON ");
+switch(flags & MAP_TYPE) {
+case MAP_PRIVATE:
+printf("MAP_PRIVATE ");
+break;
+case MAP_SHARED:
+printf("MAP_SHARED ");
+break;
+default:
+printf("[MAP_TYPE=0x%x] ", flags & MAP_TYPE);
+break;
+}
+printf("fd=%d offset=" TARGET_FMT_lx "\n", fd, offset);
+}
+#endif
+if (offset & ~TARGET_PAGE_MASK) {
+errno = EINVAL;
+goto fail;
+}
+len = TARGET_PAGE_ALIGN(len);
+if (len == 0)
+goto the_end;
+real_start = start & qemu_host_page_mask;
+if (!(flags & MAP_FIXED)) {
+abi_ulong mmap_start;
+void *p;
+host_offset = offset & qemu_host_page_mask;
+host_len = len + offset - host_offset;
+host_len = HOST_PAGE_ALIGN(host_len);
+mmap_start = mmap_find_vma(real_start, host_len);
+if (mmap_start == (abi_ulong)-1) {
+errno = ENOMEM;
+goto fail;
+}
+/* Note: we prefer to control the mapping address. It is
+especially important if qemu_host_page_size >
+qemu_real_host_page_size */
+p = mmap(g2h(mmap_start),
+host_len, prot, flags | MAP_FIXED, fd, host_offset);
+if (p == MAP_FAILED)
+goto fail;
+/* update start so that it points to the file position at 'offset' */
+host_start = (unsigned long)p;
+if (!(flags & MAP_ANONYMOUS))
+host_start += offset - host_offset;
+start = h2g(host_start);
+} else {
+int flg;
+target_ulong addr;
+if (start & ~TARGET_PAGE_MASK) {
+errno = EINVAL;
+goto fail;
+}
+end = start + len;
+real_end = HOST_PAGE_ALIGN(end);
+	/*
+	 * Test if requested memory area fits target address space
+	 * It can fail only on 64-bit host with 32-bit target.
+	 * On any other target/host host mmap() handles this error correctly.
+	 */
+if ((unsigned long)start + len - 1 > (abi_ulong) -1) {
+errno = EINVAL;
+goto fail;
+}
+for(addr = real_start; addr < real_end; addr += TARGET_PAGE_SIZE) {
+flg = page_get_flags(addr);
+if (flg & PAGE_RESERVED) {
+errno = ENXIO;
+goto fail;
+}
+}
+/* worst case: we cannot map the file because the offset is not
+aligned, so we read it */
+if (!(flags & MAP_ANONYMOUS) &&
+(offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) {
+/* msync() won't work here, so we return an error if write is
+possible while it is a shared mapping */
+if ((flags & MAP_TYPE) == MAP_SHARED &&
+(prot & PROT_WRITE)) {
+errno = EINVAL;
+goto fail;
+}
+retaddr = target_mmap(start, len, prot | PROT_WRITE,
+MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS,
+-1, 0);
+if (retaddr == -1)
+goto fail;
+pread(fd, g2h(start), len, offset);
+if (!(prot & PROT_WRITE)) {
+ret = target_mprotect(start, len, prot);
+if (ret != 0) {
+start = ret;
+goto the_end;
+}
+}
+goto the_end;
+}
+/* handle the start of the mapping */
+if (start > real_start) {
+if (real_end == real_start + qemu_host_page_size) {
+/* one single host page */
+ret = mmap_frag(real_start, start, end,
+prot, flags, fd, offset);
+if (ret == -1)
+goto fail;
+goto the_end1;
+}
+ret = mmap_frag(real_start, start, real_start + qemu_host_page_size,
+prot, flags, fd, offset);
+if (ret == -1)
+goto fail;
+real_start += qemu_host_page_size;
+}
+/* handle the end of the mapping */
+if (end < real_end) {
+ret = mmap_frag(real_end - qemu_host_page_size,
+real_end - qemu_host_page_size, real_end,
+prot, flags, fd,
+offset + real_end - qemu_host_page_size - start);
+if (ret == -1)
+goto fail;
+real_end -= qemu_host_page_size;
+}
+/* map the middle (easier) */
+if (real_start < real_end) {
+void *p;
+unsigned long offset1;
+if (flags & MAP_ANONYMOUS)
+offset1 = 0;
+else
+offset1 = offset + real_start - start;
+p = mmap(g2h(real_start), real_end - real_start,
+prot, flags, fd, offset1);
+if (p == MAP_FAILED)
+goto fail;
+}
+}
+the_end1:
+page_set_flags(start, start + len, prot | PAGE_VALID);
+the_end:
+#ifdef DEBUG_MMAP
+printf("ret=0x" TARGET_FMT_lx "\n", start);
+page_dump(stdout);
+printf("\n");
+#endif
+mmap_unlock();
+return start;
+fail:
+mmap_unlock();
+return -1;
+}
+int target_munmap(abi_ulong start, abi_ulong len)
+{
+abi_ulong end, real_start, real_end, addr;
+int prot, ret;
+#ifdef DEBUG_MMAP
+printf("munmap: start=0x%lx len=0x%lx\n", start, len);
+#endif
+if (start & ~TARGET_PAGE_MASK)
+return -EINVAL;
+len = TARGET_PAGE_ALIGN(len);
+if (len == 0)
+return -EINVAL;
+mmap_lock();
+end = start + len;
+real_start = start & qemu_host_page_mask;
+real_end = HOST_PAGE_ALIGN(end);
+if (start > real_start) {
+/* handle host page containing start */
+prot = 0;
+for(addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) {
+prot |= page_get_flags(addr);
+}
+if (real_end == real_start + qemu_host_page_size) {
+for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
+prot |= page_get_flags(addr);
+}
+end = real_end;
+}
+if (prot != 0)
+real_start += qemu_host_page_size;
+}
+if (end < real_end) {
+prot = 0;
+for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
+prot |= page_get_flags(addr);
+}
+if (prot != 0)
+real_end -= qemu_host_page_size;
+}
+ret = 0;
+/* unmap what we can */
+if (real_start < real_end) {
+ret = munmap(g2h(real_start), real_end - real_start);
+}
+if (ret == 0)
+page_set_flags(start, start + len, 0);
+mmap_unlock();
+return ret;
+}
+abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
+abi_ulong new_size, unsigned long flags,
+abi_ulong new_addr)
+{
+int prot;
+void *host_addr;
+mmap_lock();
+if (flags & MREMAP_FIXED)
+host_addr = (void *) syscall(__NR_mremap, g2h(old_addr),
+old_size, new_size,
+flags,
+new_addr);
+else if (flags & MREMAP_MAYMOVE) {
+abi_ulong mmap_start;
+mmap_start = mmap_find_vma(0, new_size);
+if (mmap_start == -1) {
+errno = ENOMEM;
+host_addr = MAP_FAILED;
+} else
+host_addr = (void *) syscall(__NR_mremap, g2h(old_addr),
+old_size, new_size,
+flags | MREMAP_FIXED,
+g2h(mmap_start));
+} else {
+host_addr = mremap(g2h(old_addr), old_size, new_size, flags);
+/* Check if address fits target address space */
+if ((unsigned long)host_addr + new_size > (abi_ulong)-1) {
+/* Revert mremap() changes */
+host_addr = mremap(g2h(old_addr), new_size, old_size, flags);
+errno = ENOMEM;
+host_addr = MAP_FAILED;
+}
+}
+if (host_addr == MAP_FAILED) {
+new_addr = -1;
+} else {
+new_addr = h2g(host_addr);
+prot = page_get_flags(old_addr);
+page_set_flags(old_addr, old_addr + old_size, 0);
+page_set_flags(new_addr, new_addr + new_size, prot | PAGE_VALID);
+}
+mmap_unlock();
+return new_addr;
+}
+int target_msync(abi_ulong start, abi_ulong len, int flags)
+{
+abi_ulong end;
+if (start & ~TARGET_PAGE_MASK)
+return -EINVAL;
+len = TARGET_PAGE_ALIGN(len);
+end = start + len;
+if (end < start)
+return -EINVAL;
+if (end == start)
+return 0;
+start &= qemu_host_page_mask;
+return msync(g2h(start), end - start, flags);
+}