commit 9bdfa4d23f4395dab89a60eb6b05a0308792bd66
author Shu-Chun Weng <scw@google.com> Mon Aug 19 11:09:47 2019 -0700
committer Laurent Vivier <laurent@vivier.eu> Wed Sep 11 08:46:17 2019 +0200
tree 34e7c3dfeb9e5998a9c29bc76734cd9cf658769a
parent 7f4341e84bb867c6e3397a978d3ee131bf8a889b

linux-user: add memfd_create

Add support for the memfd_create syscall. If the host does not have the
libc wrapper, translate to a direct syscall with NC-macro.

Buglink: https://bugs.launchpad.net/qemu/+bug/1734792
Signed-off-by: Shu-Chun Weng <scw@google.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20190819180947.180725-1-scw@google.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

linux-user/syscall.c

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index b42f59a..6928f65 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -20,6 +20,7 @@
 #include "qemu/osdep.h"
 #include "qemu/cutils.h"
 #include "qemu/path.h"
+#include "qemu/memfd.h"
 #include "qemu/queue.h"
 #include <elf.h>
 #include <endian.h>
@@ -11938,6 +11939,17 @@
         /* PowerPC specific.  */
         return do_swapcontext(cpu_env, arg1, arg2, arg3);
 #endif
+#ifdef TARGET_NR_memfd_create
+    case TARGET_NR_memfd_create:
+        p = lock_user_string(arg1);
+        if (!p) {
+            return -TARGET_EFAULT;
+        }
+        ret = get_errno(memfd_create(p, arg2));
+        fd_trans_unregister(ret);
+        unlock_user(p, arg1, 0);
+        return ret;
+#endif
 
     default:
         qemu_log_mask(LOG_UNIMP, "Unsupported syscall: %d\n", num);