This removes the need of using a temporary file for the fd.
Signed-off-by: Fuad Tabba <tabba@xxxxxxxxxx>
---
util/util.c | 25 ++++++++++++++++++++-----
1 file changed, 20 insertions(+), 5 deletions(-)
diff --git a/util/util.c b/util/util.c
index e6c0951..d6ceb5d 100644
--- a/util/util.c
+++ b/util/util.c
@@ -10,6 +10,14 @@
#include <sys/stat.h>
#include <sys/statfs.h>
+#ifndef MFD_HUGETLB
+#define MFD_HUGETLB 0x0004U
+#endif
+
+#ifndef MFD_HUGE_SHIFT
+#define MFD_HUGE_SHIFT 26
+#endif
+
static void report(const char *prefix, const char *err, va_list params)
{
char msg[1024];
@@ -96,10 +104,12 @@ static u64 get_hugepage_blk_size(const char *htlbfs_path)
static void *mmap_hugetlbfs(struct kvm *kvm, const char *htlbfs_path, u64 size)
{
- char mpath[PATH_MAX];
+ const char *name = "kvmtool";
+ unsigned int flags = 0;
int fd;
void *addr;
u64 blk_size;
+ int htsize;
blk_size = get_hugepage_blk_size(htlbfs_path);
if (blk_size == 0 || blk_size > size) {
@@ -107,13 +117,18 @@ static void *mmap_hugetlbfs(struct kvm *kvm, const char *htlbfs_path, u64 size)
(unsigned long long)blk_size, (unsigned long long)size);
}
+ htsize = __builtin_ctzl(blk_size);
+ if ((1ULL << htsize) != blk_size)
+ die("Hugepage size must be a power of 2.\n");
+
+ flags |= MFD_HUGETLB;
+ flags |= htsize << MFD_HUGE_SHIFT;
+
kvm->ram_pagesize = blk_size;
- snprintf(mpath, PATH_MAX, "%s/kvmtoolXXXXXX", htlbfs_path);
- fd = mkstemp(mpath);
+ fd = memfd_create(name, flags);
if (fd < 0)
- die("Can't open %s for hugetlbfs map\n", mpath);
- unlink(mpath);
+ die("Can't memfd_create for hugetlbfs map\n");
if (ftruncate(fd, size) < 0)
die("Can't ftruncate for mem mapping size %lld\n",
(unsigned long long)size);
--
2.38.1.431.g37b22c650d-goog
