On 04/13/2018 09:31 AM, Vladimir Sementsov-Ogievskiy wrote:
Handle nbd CACHE command. Just do read, without sending read data back.
Cache mechanism should be done by exported node driver chain.
Signed-off-by: Vladimir Sementsov-Ogievskiy <address@hidden>
---
include/block/nbd.h | 3 ++-
nbd/server.c | 10 ++++++----
2 files changed, 8 insertions(+), 5 deletions(-)
diff --git a/include/block/nbd.h b/include/block/nbd.h
index fcdcd54502..b4793d0a29 100644
--- a/include/block/nbd.h
+++ b/include/block/nbd.h
@@ -135,6 +135,7 @@ typedef struct NBDExtent {
#define NBD_FLAG_SEND_TRIM (1 << 5) /* Send TRIM (discard) */
#define NBD_FLAG_SEND_WRITE_ZEROES (1 << 6) /* Send WRITE_ZEROES */
#define NBD_FLAG_SEND_DF (1 << 7) /* Send DF (Do not Fragment) */
+#define NBD_FLAG_SEND_CACHE (1 << 8) /* Send CACHE (prefetch) */
Hmm, this flag is not documented in the upstream NBD protocol yet; are
we sure it matches the xNBD implementation? We'll want at least a
documentation patch proposed for the NBD list before taking this.