4:55 p.m.
When the server sets NBD_REPLY_FLAG_DONE on a data or block status
chunk, we can use that fact to pass (VALID|FREE) and avoid a separate
callback later just for FREE.
---
As I've been promising in other threads...
generator/states-reply-structured.c | 33 +++++++++++++++++++++++++----
1 file changed, 29 insertions(+), 4 deletions(-)
diff --git a/generator/states-reply-structured.c b/generator/states-reply-structured.c
index 2ef8d20..20b0e9e 100644
--- a/generator/states-reply-structured.c
+++ b/generator/states-reply-structured.c
@@ -18,6 +18,19 @@
/* State machine for parsing structured replies from the server. */
+static unsigned
+valid_flags (struct nbd_handle *h)
+{
+ unsigned valid = LIBNBD_CALLBACK_VALID;
+ uint16_t flags = be16toh (h->sbuf.sr.structured_reply.flags);
+
+ if (flags & NBD_REPLY_FLAG_DONE)
+ valid |= LIBNBD_CALLBACK_FREE;
+ return valid;
+}
+
+/*----- End of prologue. -----*/
+
/* STATE MACHINE */ {
REPLY.STRUCTURED_REPLY.START:
/* We've only read the simple_reply. The structured_reply is longer,
@@ -293,16 +306,19 @@
}
if (cmd->type == NBD_CMD_READ && cmd->cb.fn.read) {
int scratch = error;
+ unsigned valid = valid_flags (h);
/* Different from successful reads: inform the callback about the
* current error rather than any earlier one. If the callback fails
* without setting errno, then use the server's error below.
*/
- if (cmd->cb.fn.read (LIBNBD_CALLBACK_VALID, cmd->cb.fn_user_data,
+ if (cmd->cb.fn.read (valid, cmd->cb.fn_user_data,
cmd->data + (offset - cmd->offset),
0, offset, LIBNBD_READ_ERROR, &scratch) == -1)
if (cmd->error == 0)
cmd->error = scratch;
+ if (valid & LIBNBD_CALLBACK_FREE)
+ cmd->cb.fn.read = NULL; /* because we've freed it */
}
}
@@ -384,13 +400,16 @@
assert (cmd); /* guaranteed by CHECK */
if (cmd->cb.fn.read) {
int error = cmd->error;
+ unsigned valid = valid_flags (h);
- if (cmd->cb.fn.read (LIBNBD_CALLBACK_VALID, cmd->cb.fn_user_data,
+ if (cmd->cb.fn.read (valid, cmd->cb.fn_user_data,
cmd->data + (offset - cmd->offset),
length - sizeof offset, offset,
LIBNBD_READ_DATA, &error) == -1)
if (cmd->error == 0)
cmd->error = error ? error : EPROTO;
+ if (valid & LIBNBD_CALLBACK_FREE)
+ cmd->cb.fn.read = NULL; /* because we've freed it */
}
SET_NEXT_STATE (%FINISH);
@@ -446,13 +465,16 @@
memset (cmd->data + offset, 0, length);
if (cmd->cb.fn.read) {
int error = cmd->error;
+ unsigned valid = valid_flags (h);
- if (cmd->cb.fn.read (LIBNBD_CALLBACK_VALID, cmd->cb.fn_user_data,
+ if (cmd->cb.fn.read (valid, cmd->cb.fn_user_data,
cmd->data + offset, length,
cmd->offset + offset,
LIBNBD_READ_HOLE, &error) == -1)
if (cmd->error == 0)
cmd->error = error ? error : EPROTO;
+ if (valid & LIBNBD_CALLBACK_FREE)
+ cmd->cb.fn.read = NULL; /* because we've freed it */
}
SET_NEXT_STATE(%FINISH);
@@ -498,12 +520,15 @@
if (meta_context) {
/* Call the caller's extent function. */
int error = cmd->error;
+ unsigned valid = valid_flags (h);
- if (cmd->cb.fn.extent (LIBNBD_CALLBACK_VALID, cmd->cb.fn_user_data,
+ if (cmd->cb.fn.extent (valid, cmd->cb.fn_user_data,
meta_context->name, cmd->offset,
&h->bs_entries[1], (length-4) / 4, &error) ==
-1)
if (cmd->error == 0)
cmd->error = error ? error : EPROTO;
+ if (valid & LIBNBD_CALLBACK_FREE)
+ cmd->cb.fn.extent = NULL; /* because we've freed it */
}
else
/* Emit a debug message, but ignore it. */
--
2.20.1