From 54ebe4060fe6c4ab76c79354417612ac9cf4f95e Mon Sep 17 00:00:00 2001 From: Anton Ivanov Date: Wed, 22 Apr 2020 17:00:01 +0100 Subject: um: Use fdatasync() when mapping the UBD FSYNC command We do not need to update the metadata (atime, mtime, etc) on the UBD file and/or the COW file until UML exits. UBD image mtime is checked in UML only when opening the files. After that they are locked and used exclusively by a single UML instance, so there is no point wasting resources on updating metadata on every sync. We can sync data only. The host will always update mtime if a file has been modified upon closing it. Signed-off-by: Anton Ivanov Signed-off-by: Richard Weinberger --- arch/um/os-Linux/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/um') diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c index 044836ad7392..e4421dbc4c36 100644 --- a/arch/um/os-Linux/file.c +++ b/arch/um/os-Linux/file.c @@ -290,7 +290,7 @@ int os_write_file(int fd, const void *buf, int len) int os_sync_file(int fd) { - int n = fsync(fd); + int n = fdatasync(fd); if (n < 0) return -errno; -- cgit v1.2.3