nfs41: New include/linux/sunrpc/bc_xprt.h

Contains prototype for backchannel helper routines.
Signed-off-by: Ricardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: xprt_setup_backchannel v4.0 only inline]
    Fix compile error when CONFIG_NFS_V4_1 is not set.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Update Copyright notice and fix formatting]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

include/linux/sunrpc/bc_xprt.h

+/******************************************************************************
+
+(c) 2008 NetApp.  All Rights Reserved.
+
+NetApp provides this source code under the GPL v2 License.
+The GPL v2 license is available at
+http://opensource.org/licenses/gpl-license.php.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+******************************************************************************/
+
+/*
+ * Functions to create and manage the backchannel
+ */
+
+#ifndef _LINUX_SUNRPC_BC_XPRT_H
+#define _LINUX_SUNRPC_BC_XPRT_H
+
+#include <linux/sunrpc/svcsock.h>
+#include <linux/sunrpc/xprt.h>
+
+#ifdef CONFIG_NFS_V4_1
+struct rpc_rqst *xprt_alloc_bc_request(struct rpc_xprt *xprt);
+void xprt_free_bc_request(struct rpc_rqst *req);
+int xprt_setup_backchannel(struct rpc_xprt *, unsigned int min_reqs);
+void xprt_destroy_backchannel(struct rpc_xprt *, int max_reqs);
+#else /* CONFIG_NFS_V4_1 */
+static inline int xprt_setup_backchannel(struct rpc_xprt *xprt,
+					 unsigned int min_reqs)
+{
+	return 0;
+}
+#endif /* CONFIG_NFS_V4_1 */
+#endif /* _LINUX_SUNRPC_BC_XPRT_H */
+