bsd-user/mmap.c: Implement MAP_EXCL, required by jemalloc in head
jemalloc requires a working MAP_EXCL. Ensure that no page is double
mapped when specified. In addition, use guest_range_valid_untagged to
test for valid ranges of pages rather than an incomplete inlined version
of the test that might be wrong.
Signed-off-by: Kyle Evans <kevans@FreeBSD.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
diff --git a/bsd-user/mmap.c b/bsd-user/mmap.c
index 4ecd949..5b6ed5e 100644
--- a/bsd-user/mmap.c
+++ b/bsd-user/mmap.c
@@ -574,12 +574,10 @@
* It can fail only on 64-bit host with 32-bit target.
* On any other target/host host mmap() handles this error correctly.
*/
-#if TARGET_ABI_BITS == 32 && HOST_LONG_BITS == 64
- if ((unsigned long)start + len - 1 > (abi_ulong) -1) {
+ if (!guest_range_valid_untagged(start, len)) {
errno = EINVAL;
goto fail;
}
-#endif
/*
* worst case: we cannot map the file because the offset is not
@@ -614,6 +612,12 @@
goto the_end;
}
+ /* Reject the mapping if any page within the range is mapped */
+ if ((flags & MAP_EXCL) && page_check_range(start, len, 0) < 0) {
+ errno = EINVAL;
+ goto fail;
+ }
+
/* handle the start of the mapping */
if (start > real_start) {
if (real_end == real_start + qemu_host_page_size) {
