fix: fw_env: Prevent writing error message on special files, which don't support fsync
According to fsync specification [1] some special files (e.g., a pipe, FIFO,
or socket) don't support synchronization and return either EROFS or EINVAL.
On the linux side the sys_fsync -> do_fsync() checks if the requested file
has f_op->fsync defined. If not it returns EINVAL [2].
This commit prevents writing error messages for files (devices), which
do not support fsync().
[1] - http://man7.org/linux/man-pages/man2/fsync.2.html
[2] - http://elixir.free-electrons.com/linux/v4.13-rc6/source/fs/sync.c#L183
Signed-off-by: Lukasz Majewski <lukma@denx.de>
Acked-by: Michael Heimpold <mhei@heimpold.de>
diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c
index e50c075..965e166 100644
--- a/tools/env/fw_env.c
+++ b/tools/env/fw_env.c
@@ -1088,14 +1088,16 @@
rc = flash_write (fd_current, fd_target, dev_target);
- if (fsync (fd_current)) {
+ if (fsync(fd_current) &&
+ !(errno == EINVAL || errno == EROFS)) {
fprintf (stderr,
"fsync failed on %s: %s\n",
DEVNAME (dev_current), strerror (errno));
}
if (HaveRedundEnv) {
- if (fsync (fd_target)) {
+ if (fsync(fd_target) &&
+ !(errno == EINVAL || errno == EROFS)) {
fprintf (stderr,
"fsync failed on %s: %s\n",
DEVNAME (dev_current), strerror (errno));