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authorLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 12:30:19 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 12:30:19 -0800
commitabb359450f20c32ae03039d8736f12b1d561caf5 (patch)
tree6e8723885feb66a138f19f0ff31615dc13a8d859 /Documentation/networking/dccp.txt
parentcb600d2f83c854ec3d6660063e4466431999489b (diff)
parent4e3dbdb1392a83bd21a6ff8f6bc785495058d37c (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1436 commits) cassini: Use local-mac-address prom property for Cassini MAC address net: remove the duplicate #ifdef __KERNEL__ net: bridge: check the length of skb after nf_bridge_maybe_copy_header() netconsole: clarify stopping message netconsole: don't announce stopping if nothing happened cnic: Fix the type field in SPQ messages netfilter: fix export secctx error handling netfilter: fix the race when initializing nf_ct_expect_hash_rnd ipv4: IP defragmentation must be ECN aware net: r6040: Return proper error for r6040_init_one dcb: use after free in dcb_flushapp() dcb: unlock on error in dcbnl_ieee_get() net: ixp4xx_eth: Return proper error for eth_init_one include/linux/if_ether.h: Add #define ETH_P_LINK_CTL for HPNA and wlan local tunnel net: add POLLPRI to sock_def_readable() af_unix: Avoid socket->sk NULL OOPS in stream connect security hooks. net_sched: pfifo_head_drop problem mac80211: remove stray extern mac80211: implement off-channel TX using hw r-o-c offload mac80211: implement hardware offload for remain-on-channel ...
Diffstat (limited to 'Documentation/networking/dccp.txt')
-rw-r--r--Documentation/networking/dccp.txt20
1 files changed, 20 insertions, 0 deletions
diff --git a/Documentation/networking/dccp.txt b/Documentation/networking/dccp.txt
index 271d524a4c8d..b395ca6a49f2 100644
--- a/Documentation/networking/dccp.txt
+++ b/Documentation/networking/dccp.txt
@@ -47,6 +47,26 @@ http://linux-net.osdl.org/index.php/DCCP_Testing#Experimental_DCCP_source_tree
Socket options
==============
+DCCP_SOCKOPT_QPOLICY_ID sets the dequeuing policy for outgoing packets. It takes
+a policy ID as argument and can only be set before the connection (i.e. changes
+during an established connection are not supported). Currently, two policies are
+defined: the "simple" policy (DCCPQ_POLICY_SIMPLE), which does nothing special,
+and a priority-based variant (DCCPQ_POLICY_PRIO). The latter allows to pass an
+u32 priority value as ancillary data to sendmsg(), where higher numbers indicate
+a higher packet priority (similar to SO_PRIORITY). This ancillary data needs to
+be formatted using a cmsg(3) message header filled in as follows:
+ cmsg->cmsg_level = SOL_DCCP;
+ cmsg->cmsg_type = DCCP_SCM_PRIORITY;
+ cmsg->cmsg_len = CMSG_LEN(sizeof(uint32_t)); /* or CMSG_LEN(4) */
+
+DCCP_SOCKOPT_QPOLICY_TXQLEN sets the maximum length of the output queue. A zero
+value is always interpreted as unbounded queue length. If different from zero,
+the interpretation of this parameter depends on the current dequeuing policy
+(see above): the "simple" policy will enforce a fixed queue size by returning
+EAGAIN, whereas the "prio" policy enforces a fixed queue length by dropping the
+lowest-priority packet first. The default value for this parameter is
+initialised from /proc/sys/net/dccp/default/tx_qlen.
+
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