[Qemu-devel] [PATCH 7/9] memfd: split qemu_memfd_alloc()

[marcandre.lureau@redhat.com]

From: Marc-André Lureau <marcandre.lureau@redhat.com>

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/qemu/memfd.h |  1 +
 util/memfd.c         | 19 ++++++++++++++-----
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/include/qemu/memfd.h b/include/qemu/memfd.h
index 745a8c5..41c24d8 100644
--- a/include/qemu/memfd.h
+++ b/include/qemu/memfd.h
@@ -16,6 +16,7 @@
 #define F_SEAL_WRITE    0x0008  /* prevent writes */
 #endif
 
+int qemu_memfd_create(const char *name, size_t size, unsigned int seals);
 void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
                        int *fd);
 void qemu_memfd_free(void *ptr, size_t size, int fd);
diff --git a/util/memfd.c b/util/memfd.c
index 7c40691..31aaced 100644
--- a/util/memfd.c
+++ b/util/memfd.c
@@ -64,14 +64,10 @@ static int memfd_create(const char *name, unsigned int flags)
  * memfd with sealing, but may fallback on other methods without
  * sealing.
  */
-void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
-                       int *fd)
+int qemu_memfd_create(const char *name, size_t size, unsigned int seals)
 {
-    void *ptr;
     int mfd = -1;
 
-    *fd = -1;
-
 #ifdef CONFIG_LINUX
     if (seals) {
         mfd = memfd_create(name, MFD_ALLOW_SEALING | MFD_CLOEXEC);
@@ -117,6 +113,19 @@ void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
         }
     }
 
+    return mfd;
+}
+
+void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
+                       int *fd)
+{
+    void *ptr;
+    int mfd = qemu_memfd_create(name, size, seals);
+
+    if (mfd == -1) {
+        return NULL;
+    }
+
     ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0);
     if (ptr == MAP_FAILED) {
         perror("mmap");
-- 
2.5.5