* 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.
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.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;
+pthread_mutex_t mmap_mutex = PTHREAD_MUTEX_INITIALIZER;
static int __thread mmap_lock_count;
void mmap_lock(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);
+}
+
+void *qemu_realloc(void *ptr, size_t size)
+{
+ size_t old_size, copy;
+ void *new_ptr;
+
+ if (!ptr)
+ return qemu_malloc(size);
+ old_size = *(size_t *)((char *)ptr - 16);
+ copy = old_size < size ? old_size : size;
+ new_ptr = qemu_malloc(size);
+ memcpy(new_ptr, ptr, copy);
+ qemu_free(ptr);
+ return new_ptr;
+}
+
/* NOTE: all the constants are the HOST ones, but addresses are target. */
int target_mprotect(abi_ulong start, abi_ulong len, int prot)
{
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,
+ printf("mprotect: start=0x" TARGET_ABI_FMT_lx
+ "len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c\n", start, len,
prot & PROT_READ ? 'r' : '-',
prot & PROT_WRITE ? 'w' : '-',
prot & PROT_EXEC ? 'x' : '-');
*/
/* 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 mmap_find_vma(abi_ulong start, abi_ulong size)
{
abi_ulong addr, addr1, addr_start;
int prot;
mmap_lock();
#ifdef DEBUG_MMAP
{
- printf("mmap: start=0x" TARGET_FMT_lx
- " len=0x" TARGET_FMT_lx " prot=%c%c%c flags=",
+ printf("mmap: start=0x" TARGET_ABI_FMT_lx
+ " len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c flags=",
start, len,
prot & PROT_READ ? 'r' : '-',
prot & PROT_WRITE ? 'w' : '-',
printf("[MAP_TYPE=0x%x] ", flags & MAP_TYPE);
break;
}
- printf("fd=%d offset=" TARGET_FMT_lx "\n", fd, offset);
+ printf("fd=%d offset=" TARGET_ABI_FMT_lx "\n", fd, offset);
}
#endif
goto the_end;
real_start = start & qemu_host_page_mask;
+ /* When mapping files into a memory area larger than the file, accesses
+ to pages beyond the file size will cause a SIGBUS.
+
+ For example, if mmaping a file of 100 bytes on a host with 4K pages
+ emulating a target with 8K pages, the target expects to be able to
+ access the first 8K. But the host will trap us on any access beyond
+ 4K.
+
+ When emulating a target with a larger page-size than the hosts, we
+ may need to truncate file maps at EOF and add extra anonymous pages
+ up to the targets page boundary. */
+
+ if ((qemu_real_host_page_size < TARGET_PAGE_SIZE)
+ && !(flags & MAP_ANONYMOUS)) {
+ struct stat sb;
+
+ if (fstat (fd, &sb) == -1)
+ goto fail;
+
+ /* Are we trying to create a map beyond EOF?. */
+ if (offset + len > sb.st_size) {
+ /* If so, truncate the file map at eof aligned with
+ the hosts real pagesize. Additional anonymous maps
+ will be created beyond EOF. */
+ len = (sb.st_size - offset);
+ len += qemu_real_host_page_size - 1;
+ len &= ~(qemu_real_host_page_size - 1);
+ }
+ }
+
if (!(flags & MAP_FIXED)) {
abi_ulong mmap_start;
void *p;
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);
+ host_len, prot, flags | MAP_FIXED | MAP_ANONYMOUS, -1, 0);
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))
+ if (!(flags & MAP_ANONYMOUS)) {
+ p = mmap(g2h(mmap_start), len, prot,
+ flags | MAP_FIXED, fd, host_offset);
host_start += offset - host_offset;
+ }
start = h2g(host_start);
} else {
int flg;
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) {
page_set_flags(start, start + len, prot | PAGE_VALID);
the_end:
#ifdef DEBUG_MMAP
- printf("ret=0x" TARGET_FMT_lx "\n", start);
+ printf("ret=0x" TARGET_ABI_FMT_lx "\n", start);
page_dump(stdout);
printf("\n");
#endif
int prot, ret;
#ifdef DEBUG_MMAP
- printf("munmap: start=0x%lx len=0x%lx\n", start, len);
+ printf("munmap: start=0x" TARGET_ABI_FMT_lx " len=0x"
+ TARGET_ABI_FMT_lx "\n",
+ start, len);
#endif
if (start & ~TARGET_PAGE_MASK)
return -EINVAL;
return ret;
}
-/* XXX: currently, we only handle MAP_ANONYMOUS and not MAP_FIXED
- blocks which have been allocated starting on a host page */
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;
- unsigned long host_addr;
+ void *host_addr;
mmap_lock();
- /* XXX: use 5 args syscall */
- host_addr = (long)mremap(g2h(old_addr), old_size, new_size, flags);
- if (host_addr == -1) {
+
+ 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);
projects / qemu.git / blobdiff