summaryrefslogtreecommitdiffstats
path: root/Documentation/networking/rxrpc.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/networking/rxrpc.txt')
-rw-r--r--Documentation/networking/rxrpc.txt34
1 files changed, 34 insertions, 0 deletions
diff --git a/Documentation/networking/rxrpc.txt b/Documentation/networking/rxrpc.txt
index bce8e10a2a8e..8c70ba5dee4d 100644
--- a/Documentation/networking/rxrpc.txt
+++ b/Documentation/networking/rxrpc.txt
@@ -327,6 +327,7 @@ calls, to invoke certain actions and to report certain conditions. These are:
RXRPC_ACCEPT s-- n/a Accept new call
RXRPC_EXCLUSIVE_CALL s-- n/a Make an exclusive client call
RXRPC_UPGRADE_SERVICE s-- n/a Client call can be upgraded
+ RXRPC_TX_LENGTH s-- data len Total length of Tx data
(SRT = usable in Sendmsg / delivered by Recvmsg / Terminal message)
@@ -406,6 +407,19 @@ calls, to invoke certain actions and to report certain conditions. These are:
future communication to that server and RXRPC_UPGRADE_SERVICE should no
longer be set.
+ (*) RXRPC_TX_LENGTH
+
+ This is used to inform the kernel of the total amount of data that is
+ going to be transmitted by a call (whether in a client request or a
+ service response). If given, it allows the kernel to encrypt from the
+ userspace buffer directly to the packet buffers, rather than copying into
+ the buffer and then encrypting in place. This may only be given with the
+ first sendmsg() providing data for a call. EMSGSIZE will be generated if
+ the amount of data actually given is different.
+
+ This takes a parameter of __s64 type that indicates how much will be
+ transmitted. This may not be less than zero.
+
The symbol RXRPC__SUPPORTED is defined as one more than the highest control
message type supported. At run time this can be queried by means of the
RXRPC_SUPPORTED_CMSG socket option (see below).
@@ -577,6 +591,9 @@ A client would issue an operation by:
MSG_MORE should be set in msghdr::msg_flags on all but the last part of
the request. Multiple requests may be made simultaneously.
+ An RXRPC_TX_LENGTH control message can also be specified on the first
+ sendmsg() call.
+
If a call is intended to go to a destination other than the default
specified through connect(), then msghdr::msg_name should be set on the
first request message of that call.
@@ -764,6 +781,7 @@ The kernel interface functions are as follows:
struct sockaddr_rxrpc *srx,
struct key *key,
unsigned long user_call_ID,
+ s64 tx_total_len,
gfp_t gfp);
This allocates the infrastructure to make a new RxRPC call and assigns
@@ -780,6 +798,11 @@ The kernel interface functions are as follows:
control data buffer. It is entirely feasible to use this to point to a
kernel data structure.
+ tx_total_len is the amount of data the caller is intending to transmit
+ with this call (or -1 if unknown at this point). Setting the data size
+ allows the kernel to encrypt directly to the packet buffers, thereby
+ saving a copy. The value may not be less than -1.
+
If this function is successful, an opaque reference to the RxRPC call is
returned. The caller now holds a reference on this and it must be
properly ended.
@@ -931,6 +954,17 @@ The kernel interface functions are as follows:
This is used to find the remote peer address of a call.
+ (*) Set the total transmit data size on a call.
+
+ void rxrpc_kernel_set_tx_length(struct socket *sock,
+ struct rxrpc_call *call,
+ s64 tx_total_len);
+
+ This sets the amount of data that the caller is intending to transmit on a
+ call. It's intended to be used for setting the reply size as the request
+ size should be set when the call is begun. tx_total_len may not be less
+ than zero.
+
=======================
CONFIGURABLE PARAMETERS
OpenPOWER on IntegriCloud