Print a warning when opening a file O_DIRECT fails with EINVAL. This
saves users a lot of time trying to figure out the EINVAL error, which
is typical when attempting to open a file O_DIRECT on Linux tmpfs.
Reported-by: Deepak C Shetty <deepakcs@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
}
#endif
+#ifdef O_DIRECT
+ if (ret == -1 && errno == EINVAL && (flags & O_DIRECT)) {
+ error_report("file system may not support O_DIRECT");
+ errno = EINVAL; /* in case it was clobbered */
+ }
+#endif /* O_DIRECT */
+
return ret;
}