From: Shu-Chun Weng via Qemu-devel <qemu-devel@nongnu.org>
To: marcandre.lureau@gmail.com
Cc: arunkaly@google.com, Shu-Chun Weng <scw@google.com>,
riku.voipio@iki.fi, qemu-devel@nongnu.org, laurent@vivier.eu
Subject: [Qemu-devel] [PATCH v2] linux-user: add memfd_create
Date: Mon, 19 Aug 2019 11:08:31 -0700 [thread overview]
Message-ID: <20190819180831.179075-1-scw@google.com> (raw)
In-Reply-To: <CAFEAcA-GWR6_wGCMWkMHttU3ARJPqfADvNTnqQUU_OzcWgHHuQ@mail.gmail.com>
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>
---
include/qemu/memfd.h | 4 ++++
linux-user/syscall.c | 11 +++++++++++
util/memfd.c | 2 +-
3 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/include/qemu/memfd.h b/include/qemu/memfd.h
index d551c28b68..975b6bdb77 100644
--- a/include/qemu/memfd.h
+++ b/include/qemu/memfd.h
@@ -32,6 +32,10 @@
#define MFD_HUGE_SHIFT 26
#endif
+#if defined CONFIG_LINUX && !defined CONFIG_MEMFD
+int memfd_create(const char *name, unsigned int flags);
+#endif
+
int qemu_memfd_create(const char *name, size_t size, bool hugetlb,
uint64_t hugetlbsize, unsigned int seals, Error **errp);
bool qemu_memfd_alloc_check(void);
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 8367cb138d..b506c1f40e 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 <elf.h>
#include <endian.h>
#include <grp.h>
@@ -11938,6 +11939,16 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
/* 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));
+ unlock_user(p, arg1, 0);
+ return ret;
+#endif
default:
qemu_log_mask(LOG_UNIMP, "Unsupported syscall: %d\n", num);
diff --git a/util/memfd.c b/util/memfd.c
index 00334e5b21..4a3c07e0be 100644
--- a/util/memfd.c
+++ b/util/memfd.c
@@ -35,7 +35,7 @@
#include <sys/syscall.h>
#include <asm/unistd.h>
-static int memfd_create(const char *name, unsigned int flags)
+int memfd_create(const char *name, unsigned int flags)
{
#ifdef __NR_memfd_create
return syscall(__NR_memfd_create, name, flags);
--
2.23.0.rc1.153.gdeed80330f-goog
next prev parent reply other threads:[~2019-08-19 18:09 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-16 21:10 [Qemu-devel] [PATCH] linux-user: add memfd_create Shu-Chun Weng via Qemu-devel
2019-08-18 21:57 ` Philippe Mathieu-Daudé
2019-08-19 7:12 ` Marc-André Lureau
2019-08-19 11:56 ` Peter Maydell
2019-08-19 18:08 ` Shu-Chun Weng via Qemu-devel [this message]
2019-08-19 18:09 ` [Qemu-devel] [PATCH v3] " Shu-Chun Weng via Qemu-devel
2019-08-23 16:48 ` Laurent Vivier
2019-09-10 16:49 ` Laurent Vivier
2019-08-23 16:42 ` [Qemu-devel] [PATCH] " Laurent Vivier
2019-09-10 8:16 ` Laurent Vivier
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