[POWERPC] qe: add function qe_clock_source()

[linux-2.6-omap-h63xx.git] / Documentation / networking / dccp.txt

diff --git a/Documentation/networking/dccp.txt b/Documentation/networking/dccp.txt
index dda15886bcb51045ad5168dcafb8e0e5048c6301..afb66f9a8aff5aa3f32ea32ea65784ac80d6131e 100644 (file)
--- a/Documentation/networking/dccp.txt
+++ b/Documentation/networking/dccp.txt
@@ -19,7 +19,8 @@ for real time and multimedia traffic.
 
 It has a base protocol and pluggable congestion control IDs (CCIDs).
 
-It is at experimental RFC status and the homepage for DCCP as a protocol is at:
+It is at proposed standard RFC status and the homepage for DCCP as a protocol
+is at:
        http://www.read.cs.ucla.edu/dccp/
 
 Missing features
@@ -34,14 +35,16 @@ The known bugs are at:
 Socket options
 ==============
 
-DCCP_SOCKOPT_PACKET_SIZE is used for CCID3 to set default packet size for
-calculations.
-
 DCCP_SOCKOPT_SERVICE sets the service. The specification mandates use of
 service codes (RFC 4340, sec. 8.1.2); if this socket option is not set,
 the socket will fall back to 0 (which means that no meaningful service code
-is present). Connecting sockets set at most one service option; for
-listening sockets, multiple service codes can be specified.
+is present). On active sockets this is set before connect(); specifying more
+than one code has no effect (all subsequent service codes are ignored). The
+case is different for passive sockets, where multiple service codes (up to 32)
+can be set before calling bind().
+
+DCCP_SOCKOPT_GET_CUR_MPS is read-only and retrieves the current maximum packet
+size (application payload size) in bytes, see RFC 4340, section 14.
 
 DCCP_SOCKOPT_SEND_CSCOV and DCCP_SOCKOPT_RECV_CSCOV are used for setting the
 partial checksum coverage (RFC 4340, sec. 9.2). The default is that checksums
@@ -52,12 +55,23 @@ be enabled at the receiver, too with suitable choice of CsCov.
 DCCP_SOCKOPT_SEND_CSCOV sets the sender checksum coverage. Values in the
        range 0..15 are acceptable. The default setting is 0 (full coverage),
        values between 1..15 indicate partial coverage.
-DCCP_SOCKOPT_SEND_CSCOV is for the receiver and has a different meaning: it
+DCCP_SOCKOPT_RECV_CSCOV is for the receiver and has a different meaning: it
        sets a threshold, where again values 0..15 are acceptable. The default
        of 0 means that all packets with a partial coverage will be discarded.
        Values in the range 1..15 indicate that packets with minimally such a
        coverage value are also acceptable. The higher the number, the more
-       restrictive this setting (see [RFC 4340, sec. 9.2.1]).
+       restrictive this setting (see [RFC 4340, sec. 9.2.1]). Partial coverage
+       settings are inherited to the child socket after accept().
+
+The following two options apply to CCID 3 exclusively and are getsockopt()-only.
+In either case, a TFRC info struct (defined in <linux/tfrc.h>) is returned.
+DCCP_SOCKOPT_CCID_RX_INFO
+       Returns a `struct tfrc_rx_info' in optval; the buffer for optval and
+       optlen must be set to at least sizeof(struct tfrc_rx_info).
+DCCP_SOCKOPT_CCID_TX_INFO
+       Returns a `struct tfrc_tx_info' in optval; the buffer for optval and
+       optlen must be set to at least sizeof(struct tfrc_tx_info).
+
 
 Sysctl variables
 ================
@@ -104,9 +118,14 @@ tx_qlen = 5
        The size of the transmit buffer in packets. A value of 0 corresponds
        to an unbounded transmit buffer.
 
+sync_ratelimit = 125 ms
+       The timeout between subsequent DCCP-Sync packets sent in response to
+       sequence-invalid packets on the same socket (RFC 4340, 7.5.4). The unit
+       of this parameter is milliseconds; a value of 0 disables rate-limiting.
+
 Notes
 =====
 
 DCCP does not travel through NAT successfully at present on many boxes. This is
-because the checksum covers the psuedo-header as per TCP and UDP. Linux NAT
+because the checksum covers the pseudo-header as per TCP and UDP. Linux NAT
 support for DCCP has been added.