Merge branch 'extension-info'

Signed-off-by: Wouter Verhelst <w@uter.be>

cliserv.h

@@ -94,24 +94,35 @@ void writeit(int f, void *buf, size_t len);
 					 * served */
 
 /* Options that the client can select to the server */
-#define NBD_OPT_EXPORT_NAME	(1)	/** Client wants to select a named export (is followed by name of export) */
-#define NBD_OPT_ABORT		(2)	/** Client wishes to abort negotiation */
-#define NBD_OPT_LIST		(3)	/** Client request list of supported exports (not followed by data) */
-#define NBD_OPT_STARTTLS	(5)	/** Client wishes to initiate TLS */
+#define NBD_OPT_EXPORT_NAME	(1)	/**< Client wants to select a named export (is followed by name of export) */
+#define NBD_OPT_ABORT		(2)	/**< Client wishes to abort negotiation */
+#define NBD_OPT_LIST		(3)	/**< Client request list of supported exports (not followed by data) */
+#define NBD_OPT_STARTTLS	(5)	/**< Client wishes to initiate TLS */
+#define NBD_OPT_INFO		(6)	/**< Client wants information about the given export */
+#define NBD_OPT_GO		(7)	/**< Client wants to select the given and move to the transmission phase */
 
 /* Replies the server can send during negotiation */
-#define NBD_REP_ACK		(1)	/** ACK a request. Data: option number to be acked */
-#define NBD_REP_SERVER		(2)	/** Reply to NBD_OPT_LIST (one of these per server; must be followed by NBD_REP_ACK to signal the end of the list */
+#define NBD_REP_ACK		(1)	/**< ACK a request. Data: option number to be acked */
+#define NBD_REP_SERVER		(2)	/**< Reply to NBD_OPT_LIST (one of these per server; must be followed by NBD_REP_ACK to signal the end of the list */
+#define NBD_REP_INFO		(3)	/**< Reply to NBD_OPT_INFO */
 #define NBD_REP_FLAG_ERROR	(1 << 31)	/** If the high bit is set, the reply is an error */
-#define NBD_REP_ERR_UNSUP	(1 | NBD_REP_FLAG_ERROR)	/** Client requested an option not understood by this version of the server */
-#define NBD_REP_ERR_POLICY	(2 | NBD_REP_FLAG_ERROR)	/** Client requested an option not allowed by server configuration. (e.g., the option was disabled) */
-#define NBD_REP_ERR_INVALID	(3 | NBD_REP_FLAG_ERROR)	/** Client issued an invalid request */
-#define NBD_REP_ERR_PLATFORM	(4 | NBD_REP_FLAG_ERROR)	/** Option not supported on this platform */
-#define NBD_REP_ERR_TLS_REQD	(5 | NBD_REP_FLAG_ERROR)	/** TLS required */
+#define NBD_REP_ERR_UNSUP	(1 | NBD_REP_FLAG_ERROR)	/**< Client requested an option not understood by this version of the server */
+#define NBD_REP_ERR_POLICY	(2 | NBD_REP_FLAG_ERROR)	/**< Client requested an option not allowed by server configuration. (e.g., the option was disabled) */
+#define NBD_REP_ERR_INVALID	(3 | NBD_REP_FLAG_ERROR)	/**< Client issued an invalid request */
+#define NBD_REP_ERR_PLATFORM	(4 | NBD_REP_FLAG_ERROR)	/**< Option not supported on this platform */
+#define NBD_REP_ERR_TLS_REQD	(5 | NBD_REP_FLAG_ERROR)	/**< TLS required */
+#define NBD_REP_ERR_UNKNOWN	(6 | NBD_REP_FLAG_ERROR)	/**< NBD_OPT_INFO or ..._GO requested on unknown export */
+#define NBD_REP_ERR_BLOCK_SIZE_REQD (8 | NBD_REP_FLAG_ERROR)	/**< Server is not willing to serve the export without the block size being negotiated */
 
 /* Global flags */
-#define NBD_FLAG_FIXED_NEWSTYLE (1 << 0)	/* new-style export that actually supports extending */
-#define NBD_FLAG_NO_ZEROES	(1 << 1)	/* we won't send the 128 bits of zeroes if the client sends NBD_FLAG_C_NO_ZEROES */
-/* Flags from client to server. Only one such option currently. */
+#define NBD_FLAG_FIXED_NEWSTYLE (1 << 0)	/**< new-style export that actually supports extending */
+#define NBD_FLAG_NO_ZEROES	(1 << 1)	/**< we won't send the 128 bits of zeroes if the client sends NBD_FLAG_C_NO_ZEROES */
+/* Flags from client to server. */
 #define NBD_FLAG_C_FIXED_NEWSTYLE NBD_FLAG_FIXED_NEWSTYLE
 #define NBD_FLAG_C_NO_ZEROES	NBD_FLAG_NO_ZEROES
+
+/* Info types */
+#define NBD_INFO_EXPORT		(0)
+#define NBD_INFO_NAME		(1)
+#define NBD_INFO_DESCRIPTION	(2)
+#define NBD_INFO_BLOCK_SIZE	(3)