Add support for setting/clearing the O_DIRECT flag on a file
descriptor. This will be used for enabling O_DIRECT in the main
migration channel when multifd is not in use.
Signed-off-by: Fabiano Rosas <faro...@suse.de>
---
include/io/channel-file.h | 8 ++++++++
io/channel-file.c | 25 +++++++++++++++++++++++++
2 files changed, 33 insertions(+)
diff --git a/include/io/channel-file.h b/include/io/channel-file.h
index d373a4e44d..ecb4450e8e 100644
--- a/include/io/channel-file.h
+++ b/include/io/channel-file.h
@@ -107,4 +107,12 @@ qio_channel_file_new_path(const char *path,
mode_t mode,
Error **errp);
+/**
+ * qio_channel_file_set_direct_io:
+ * @ioc: the QIOChannel object
+ * @enabled: the desired state of the O_DIRECT flag
+ * @errp: pointer to initialized error object
+ */
+void qio_channel_file_set_direct_io(QIOChannel *ioc, bool enabled,
+ Error **errp);
#endif /* QIO_CHANNEL_FILE_H */
diff --git a/io/channel-file.c b/io/channel-file.c
index 2ea8d08360..a89cd3a6d5 100644
--- a/io/channel-file.c
+++ b/io/channel-file.c
@@ -231,6 +231,31 @@ static int qio_channel_file_set_blocking(QIOChannel *ioc,
#endif
}
+void qio_channel_file_set_direct_io(QIOChannel *ioc, bool enabled, Error
**errp)
+{
+#ifdef O_DIRECT
+ QIOChannelFile *fioc = QIO_CHANNEL_FILE(ioc);
+ int flags = fcntl(fioc->fd, F_GETFL);
+
+ if (flags == -1) {
+ error_setg_errno(errp, errno, "Unable to read file descriptor flags");
+ return;
+ }
+
+ if (enabled) {
+ flags |= O_DIRECT;
+ } else {
+ flags &= ~O_DIRECT;
+ }
+
+ if (fcntl(fioc->fd, F_SETFL, flags) == -1) {
+ error_setg_errno(errp, errno, "Unable to set file descriptor flags");
+ return;
+ }
+#else
+ error_setg(errp, "System does not support O_DIRECT");
+#endif
+}
static off_t qio_channel_file_seek(QIOChannel *ioc,
off_t offset,
--
2.35.3
