diff mbox series

[v6,08/17] nbd/server: Prepare to send extended header replies

Message ID 20230829175826.377251-27-eblake@redhat.com
State New
Headers show
Series qemu patches for 64-bit NBD extensions | expand

Commit Message

Eric Blake Aug. 29, 2023, 5:58 p.m. UTC 
Although extended mode is not yet enabled, once we do turn it on, we
need to reply with extended headers to all messages.  Update the low
level entry points necessary so that all other callers automatically
get the right header based on the current mode.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
---

v5: s/iov->iov_len/iov[0].iov_len/ [Vladimir], add R-b

v4: new patch, split out from v3 9/14
---
 nbd/server.c | 30 ++++++++++++++++++++++--------
 1 file changed, 22 insertions(+), 8 deletions(-)
diff mbox series

Patch

diff --git a/nbd/server.c b/nbd/server.c
index b8e8694f3f4..efeb2e12bd2 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -1950,8 +1950,6 @@  static inline void set_be_chunk(NBDClient *client, struct iovec *iov,
                                 size_t niov, uint16_t flags, uint16_t type,
                                 NBDRequest *request)
 {
-    /* TODO - handle structured vs. extended replies */
-    NBDStructuredReplyChunk *chunk = iov->iov_base;
     size_t i, length = 0;

     for (i = 1; i < niov; i++) {
@@ -1959,12 +1957,26 @@  static inline void set_be_chunk(NBDClient *client, struct iovec *iov,
     }
     assert(length <= NBD_MAX_BUFFER_SIZE + sizeof(NBDStructuredReadData));

-    iov[0].iov_len = sizeof(*chunk);
-    stl_be_p(&chunk->magic, NBD_STRUCTURED_REPLY_MAGIC);
-    stw_be_p(&chunk->flags, flags);
-    stw_be_p(&chunk->type, type);
-    stq_be_p(&chunk->cookie, request->cookie);
-    stl_be_p(&chunk->length, length);
+    if (client->mode >= NBD_MODE_EXTENDED) {
+        NBDExtendedReplyChunk *chunk = iov->iov_base;
+
+        iov[0].iov_len = sizeof(*chunk);
+        stl_be_p(&chunk->magic, NBD_EXTENDED_REPLY_MAGIC);
+        stw_be_p(&chunk->flags, flags);
+        stw_be_p(&chunk->type, type);
+        stq_be_p(&chunk->cookie, request->cookie);
+        stq_be_p(&chunk->offset, request->from);
+        stq_be_p(&chunk->length, length);
+    } else {
+        NBDStructuredReplyChunk *chunk = iov->iov_base;
+
+        iov[0].iov_len = sizeof(*chunk);
+        stl_be_p(&chunk->magic, NBD_STRUCTURED_REPLY_MAGIC);
+        stw_be_p(&chunk->flags, flags);
+        stw_be_p(&chunk->type, type);
+        stq_be_p(&chunk->cookie, request->cookie);
+        stl_be_p(&chunk->length, length);
+    }
 }

 static int coroutine_fn nbd_co_send_chunk_done(NBDClient *client,
@@ -2515,6 +2527,8 @@  static coroutine_fn int nbd_send_generic_reply(NBDClient *client,
 {
     if (client->mode >= NBD_MODE_STRUCTURED && ret < 0) {
         return nbd_co_send_chunk_error(client, request, -ret, error_msg, errp);
+    } else if (client->mode >= NBD_MODE_EXTENDED) {
+        return nbd_co_send_chunk_done(client, request, errp);
     } else {
         return nbd_co_send_simple_reply(client, request, ret < 0 ? -ret : 0,
                                         NULL, 0, errp);