drbd: add packet_type 27 (return_code_only) to netlink api

In case we ever should add an other packet type,
we must not reuse 27, as that currently used for
"empty" return code only replies.
Document it as such.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 80a389d24cdd4b1a0153f374f1d84411f3fad220..6a6dde6c51c6076bd5346d09a6addc6113aad8fc 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -2195,7 +2195,8 @@ static void drbd_connector_callback(struct cn_msg *req, struct netlink_skb_parms
                goto fail;
        }
 
-       if (nlp->packet_type >= P_nl_after_last_packet) {
+       if (nlp->packet_type >= P_nl_after_last_packet ||
+           nlp->packet_type == P_return_code_only) {
                retcode = ERR_PACKET_NR;
                goto fail;
        }
@@ -2219,7 +2220,7 @@ static void drbd_connector_callback(struct cn_msg *req, struct netlink_skb_parms
        reply = (struct drbd_nl_cfg_reply *) cn_reply->data;
 
        reply->packet_type =
-               cm->reply_body_size ? nlp->packet_type : P_nl_after_last_packet;
+               cm->reply_body_size ? nlp->packet_type : P_return_code_only;
        reply->minor = nlp->drbd_minor;
        reply->ret_code = NO_ERROR; /* Might by modified by cm->function. */
        /* reply->tag_list; might be modified by cm->function. */
@@ -2525,6 +2526,7 @@ void drbd_nl_send_reply(struct cn_msg *req, int ret_code)
        cn_reply->len = sizeof(struct drbd_nl_cfg_reply);
        cn_reply->flags = 0;
 
+       reply->packet_type = P_return_code_only;
        reply->minor = ((struct drbd_nl_cfg_req *)req->data)->drbd_minor;
        reply->ret_code = ret_code;
 

diff --git a/include/linux/drbd_nl.h b/include/linux/drbd_nl.h
index 8cde3945d1f7d491b700336ebe350d13fbb18a67..6fc614b06c4dcea6b1935ef0ede6d6c8faf92400 100644 (file)
--- a/include/linux/drbd_nl.h
+++ b/include/linux/drbd_nl.h
@@ -146,9 +146,13 @@ NL_PACKET(new_c_uuid, 26,
        NL_BIT(         63,     T_MANDATORY,    clear_bm)
 )
 
+#ifdef NL_RESPONSE
+NL_RESPONSE(return_code_only, 27)
+#endif
+
 #undef NL_PACKET
 #undef NL_INTEGER
 #undef NL_INT64
 #undef NL_BIT
 #undef NL_STRING
-
+#undef NL_RESPONSE

diff --git a/include/linux/drbd_tag_magic.h b/include/linux/drbd_tag_magic.h
index fcdff8410e99ddad7f1dac756bd915aefce5c494..f14a165e82dc162ef0306d6dc8d9d7266a816387 100644 (file)
--- a/include/linux/drbd_tag_magic.h
+++ b/include/linux/drbd_tag_magic.h
@@ -7,6 +7,7 @@
 /* declare packet_type enums */
 enum packet_types {
 #define NL_PACKET(name, number, fields) P_ ## name = number,
+#define NL_RESPONSE(name, number) P_ ## name = number,
 #define NL_INTEGER(pn, pr, member)
 #define NL_INT64(pn, pr, member)
 #define NL_BIT(pn, pr, member)