linux-user: use libc wrapper instead of direct mremap syscall

This commit essentially reverts commit
3af72a4d, which has replaced
five-argument calls to mremap() by direct mremap syscalls for
compatibility with glibc older than version 2.4.

The direct syscall was buggy for 64bit targets on 32bit hosts
because of the default integer type promotions. Since glibc-2.4
is now a decade old, we can remove this workaround.
Signed-off-by: NFelix Janda <felix.janda@posteo.de>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

linux-user/mmap.c

@@ -17,8 +17,6 @@
  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 #include "qemu/osdep.h"
-#include <linux/mman.h>
-#include <linux/unistd.h>
 
 #include "qemu.h"
 #include "qemu-common.h"
@@ -681,10 +679,8 @@ abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
     mmap_lock();
 
     if (flags & MREMAP_FIXED) {
-        host_addr = (void *) syscall(__NR_mremap, g2h(old_addr),
-                                     old_size, new_size,
-                                     flags,
-                                     g2h(new_addr));
+        host_addr = mremap(g2h(old_addr), old_size, new_size,
+                           flags, g2h(new_addr));
 
         if (reserved_va && host_addr != MAP_FAILED) {
             /* If new and old addresses overlap then the above mremap will
@@ -700,10 +696,8 @@ abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
             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));
+            host_addr = mremap(g2h(old_addr), old_size, new_size,
+                               flags | MREMAP_FIXED, g2h(mmap_start));
             if (reserved_va) {
                 mmap_reserve(old_addr, old_size);
             }