nfsd41: sunrpc: Added rpc server-side backchannel handling
When the call direction is a reply, copy the xid and call direction into the
req->rq_private_buf.head[0].iov_base otherwise rpc_verify_header returns
rpc_garbage.
Signed-off-by: Rahul Iyer <iyer@netapp.com>
Signed-off-by: Mike Sager <sager@netapp.com>
Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[get rid of CONFIG_NFSD_V4_1]
[sunrpc: refactoring of svc_tcp_recvfrom]
[nfsd41: sunrpc: create common send routine for the fore and the back channels]
[nfsd41: sunrpc: Use free_page() to free server backchannel pages]
[nfsd41: sunrpc: Document server backchannel locking]
[nfsd41: sunrpc: remove bc_connect_worker()]
[nfsd41: sunrpc: Define xprt_server_backchannel()[
[nfsd41: sunrpc: remove bc_close and bc_init_auto_disconnect dummy functions]
[nfsd41: sunrpc: eliminate unneeded switch statement in xs_setup_tcp()]
[nfsd41: sunrpc: Don't auto close the server backchannel connection]
[nfsd41: sunrpc: Remove unused functions]
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: change bc_sock to bc_xprt]
[nfsd41: sunrpc: move struct rpc_buffer def into a common header file]
[nfsd41: sunrpc: use rpc_sleep in bc_send_request so not to block on mutex]
[removed cosmetic changes]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[sunrpc: add new xprt class for nfsv4.1 backchannel]
[sunrpc: v2.1 change handling of auto_close and init_auto_disconnect operations for the nfsv4.1 backchannel]
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
[reverted more cosmetic leftovers]
[got rid of xprt_server_backchannel]
[separated "nfsd41: sunrpc: add new xprt class for nfsv4.1 backchannel"]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Cc: Trond Myklebust <trond.myklebust@netapp.com>
[sunrpc: change idle timeout value for the backchannel]
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Acked-by: Trond Myklebust <trond.myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 62438f3..d9a2b81 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -32,6 +32,7 @@
#include <linux/tcp.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/sched.h>
+#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/xprtsock.h>
#include <linux/file.h>
#ifdef CONFIG_NFS_V4_1
@@ -43,6 +44,7 @@
#include <net/udp.h>
#include <net/tcp.h>
+#include "sunrpc.h"
/*
* xprtsock tunables
*/
@@ -2098,6 +2100,134 @@
xprt->stat.bklog_u);
}
+/*
+ * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
+ * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
+ * to use the server side send routines.
+ */
+void *bc_malloc(struct rpc_task *task, size_t size)
+{
+ struct page *page;
+ struct rpc_buffer *buf;
+
+ BUG_ON(size > PAGE_SIZE - sizeof(struct rpc_buffer));
+ page = alloc_page(GFP_KERNEL);
+
+ if (!page)
+ return NULL;
+
+ buf = page_address(page);
+ buf->len = PAGE_SIZE;
+
+ return buf->data;
+}
+
+/*
+ * Free the space allocated in the bc_alloc routine
+ */
+void bc_free(void *buffer)
+{
+ struct rpc_buffer *buf;
+
+ if (!buffer)
+ return;
+
+ buf = container_of(buffer, struct rpc_buffer, data);
+ free_page((unsigned long)buf);
+}
+
+/*
+ * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
+ * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
+ */
+static int bc_sendto(struct rpc_rqst *req)
+{
+ int len;
+ struct xdr_buf *xbufp = &req->rq_snd_buf;
+ struct rpc_xprt *xprt = req->rq_xprt;
+ struct sock_xprt *transport =
+ container_of(xprt, struct sock_xprt, xprt);
+ struct socket *sock = transport->sock;
+ unsigned long headoff;
+ unsigned long tailoff;
+
+ /*
+ * Set up the rpc header and record marker stuff
+ */
+ xs_encode_tcp_record_marker(xbufp);
+
+ tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
+ headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
+ len = svc_send_common(sock, xbufp,
+ virt_to_page(xbufp->head[0].iov_base), headoff,
+ xbufp->tail[0].iov_base, tailoff);
+
+ if (len != xbufp->len) {
+ printk(KERN_NOTICE "Error sending entire callback!\n");
+ len = -EAGAIN;
+ }
+
+ return len;
+}
+
+/*
+ * The send routine. Borrows from svc_send
+ */
+static int bc_send_request(struct rpc_task *task)
+{
+ struct rpc_rqst *req = task->tk_rqstp;
+ struct svc_xprt *xprt;
+ struct svc_sock *svsk;
+ u32 len;
+
+ dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
+ /*
+ * Get the server socket associated with this callback xprt
+ */
+ xprt = req->rq_xprt->bc_xprt;
+ svsk = container_of(xprt, struct svc_sock, sk_xprt);
+
+ /*
+ * Grab the mutex to serialize data as the connection is shared
+ * with the fore channel
+ */
+ if (!mutex_trylock(&xprt->xpt_mutex)) {
+ rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL);
+ if (!mutex_trylock(&xprt->xpt_mutex))
+ return -EAGAIN;
+ rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task);
+ }
+ if (test_bit(XPT_DEAD, &xprt->xpt_flags))
+ len = -ENOTCONN;
+ else
+ len = bc_sendto(req);
+ mutex_unlock(&xprt->xpt_mutex);
+
+ if (len > 0)
+ len = 0;
+
+ return len;
+}
+
+/*
+ * The close routine. Since this is client initiated, we do nothing
+ */
+
+static void bc_close(struct rpc_xprt *xprt)
+{
+ return;
+}
+
+/*
+ * The xprt destroy routine. Again, because this connection is client
+ * initiated, we do nothing
+ */
+
+static void bc_destroy(struct rpc_xprt *xprt)
+{
+ return;
+}
+
static struct rpc_xprt_ops xs_udp_ops = {
.set_buffer_size = xs_udp_set_buffer_size,
.reserve_xprt = xprt_reserve_xprt_cong,
@@ -2134,6 +2264,22 @@
.print_stats = xs_tcp_print_stats,
};
+/*
+ * The rpc_xprt_ops for the server backchannel
+ */
+
+static struct rpc_xprt_ops bc_tcp_ops = {
+ .reserve_xprt = xprt_reserve_xprt,
+ .release_xprt = xprt_release_xprt,
+ .buf_alloc = bc_malloc,
+ .buf_free = bc_free,
+ .send_request = bc_send_request,
+ .set_retrans_timeout = xprt_set_retrans_timeout_def,
+ .close = bc_close,
+ .destroy = bc_destroy,
+ .print_stats = xs_tcp_print_stats,
+};
+
static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
unsigned int slot_table_size)
{
