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/svcsock.c b/net/sunrpc/svcsock.c
index 76a380d..ccc5e83 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -49,6 +49,7 @@
#include <linux/sunrpc/msg_prot.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/stats.h>
+#include <linux/sunrpc/xprt.h>
#define RPCDBG_FACILITY RPCDBG_SVCXPRT
@@ -153,49 +154,27 @@
}
/*
- * Generic sendto routine
+ * send routine intended to be shared by the fore- and back-channel
*/
-static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
+int svc_send_common(struct socket *sock, struct xdr_buf *xdr,
+ struct page *headpage, unsigned long headoffset,
+ struct page *tailpage, unsigned long tailoffset)
{
- struct svc_sock *svsk =
- container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
- struct socket *sock = svsk->sk_sock;
- int slen;
- union {
- struct cmsghdr hdr;
- long all[SVC_PKTINFO_SPACE / sizeof(long)];
- } buffer;
- struct cmsghdr *cmh = &buffer.hdr;
- int len = 0;
int result;
int size;
struct page **ppage = xdr->pages;
size_t base = xdr->page_base;
unsigned int pglen = xdr->page_len;
unsigned int flags = MSG_MORE;
- RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
+ int slen;
+ int len = 0;
slen = xdr->len;
- if (rqstp->rq_prot == IPPROTO_UDP) {
- struct msghdr msg = {
- .msg_name = &rqstp->rq_addr,
- .msg_namelen = rqstp->rq_addrlen,
- .msg_control = cmh,
- .msg_controllen = sizeof(buffer),
- .msg_flags = MSG_MORE,
- };
-
- svc_set_cmsg_data(rqstp, cmh);
-
- if (sock_sendmsg(sock, &msg, 0) < 0)
- goto out;
- }
-
/* send head */
if (slen == xdr->head[0].iov_len)
flags = 0;
- len = kernel_sendpage(sock, rqstp->rq_respages[0], 0,
+ len = kernel_sendpage(sock, headpage, headoffset,
xdr->head[0].iov_len, flags);
if (len != xdr->head[0].iov_len)
goto out;
@@ -219,16 +198,58 @@
base = 0;
ppage++;
}
+
/* send tail */
if (xdr->tail[0].iov_len) {
- result = kernel_sendpage(sock, rqstp->rq_respages[0],
- ((unsigned long)xdr->tail[0].iov_base)
- & (PAGE_SIZE-1),
- xdr->tail[0].iov_len, 0);
-
+ result = kernel_sendpage(sock, tailpage, tailoffset,
+ xdr->tail[0].iov_len, 0);
if (result > 0)
len += result;
}
+
+out:
+ return len;
+}
+
+
+/*
+ * Generic sendto routine
+ */
+static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
+{
+ struct svc_sock *svsk =
+ container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
+ struct socket *sock = svsk->sk_sock;
+ union {
+ struct cmsghdr hdr;
+ long all[SVC_PKTINFO_SPACE / sizeof(long)];
+ } buffer;
+ struct cmsghdr *cmh = &buffer.hdr;
+ int len = 0;
+ unsigned long tailoff;
+ unsigned long headoff;
+ RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
+
+ if (rqstp->rq_prot == IPPROTO_UDP) {
+ struct msghdr msg = {
+ .msg_name = &rqstp->rq_addr,
+ .msg_namelen = rqstp->rq_addrlen,
+ .msg_control = cmh,
+ .msg_controllen = sizeof(buffer),
+ .msg_flags = MSG_MORE,
+ };
+
+ svc_set_cmsg_data(rqstp, cmh);
+
+ if (sock_sendmsg(sock, &msg, 0) < 0)
+ goto out;
+ }
+
+ tailoff = ((unsigned long)xdr->tail[0].iov_base) & (PAGE_SIZE-1);
+ headoff = 0;
+ len = svc_send_common(sock, xdr, rqstp->rq_respages[0], headoff,
+ rqstp->rq_respages[0], tailoff);
+
out:
dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n",
svsk, xdr->head[0].iov_base, xdr->head[0].iov_len,
@@ -951,6 +972,57 @@
return -EAGAIN;
}
+static int svc_process_calldir(struct svc_sock *svsk, struct svc_rqst *rqstp,
+ struct rpc_rqst **reqpp, struct kvec *vec)
+{
+ struct rpc_rqst *req = NULL;
+ u32 *p;
+ u32 xid;
+ u32 calldir;
+ int len;
+
+ len = svc_recvfrom(rqstp, vec, 1, 8);
+ if (len < 0)
+ goto error;
+
+ p = (u32 *)rqstp->rq_arg.head[0].iov_base;
+ xid = *p++;
+ calldir = *p;
+
+ if (calldir == 0) {
+ /* REQUEST is the most common case */
+ vec[0] = rqstp->rq_arg.head[0];
+ } else {
+ /* REPLY */
+ if (svsk->sk_bc_xprt)
+ req = xprt_lookup_rqst(svsk->sk_bc_xprt, xid);
+
+ if (!req) {
+ printk(KERN_NOTICE
+ "%s: Got unrecognized reply: "
+ "calldir 0x%x sk_bc_xprt %p xid %08x\n",
+ __func__, ntohl(calldir),
+ svsk->sk_bc_xprt, xid);
+ vec[0] = rqstp->rq_arg.head[0];
+ goto out;
+ }
+
+ memcpy(&req->rq_private_buf, &req->rq_rcv_buf,
+ sizeof(struct xdr_buf));
+ /* copy the xid and call direction */
+ memcpy(req->rq_private_buf.head[0].iov_base,
+ rqstp->rq_arg.head[0].iov_base, 8);
+ vec[0] = req->rq_private_buf.head[0];
+ }
+ out:
+ vec[0].iov_base += 8;
+ vec[0].iov_len -= 8;
+ len = svsk->sk_reclen - 8;
+ error:
+ *reqpp = req;
+ return len;
+}
+
/*
* Receive data from a TCP socket.
*/
@@ -962,6 +1034,7 @@
int len;
struct kvec *vec;
int pnum, vlen;
+ struct rpc_rqst *req = NULL;
dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
@@ -975,9 +1048,27 @@
vec = rqstp->rq_vec;
vec[0] = rqstp->rq_arg.head[0];
vlen = PAGE_SIZE;
+
+ /*
+ * We have enough data for the whole tcp record. Let's try and read the
+ * first 8 bytes to get the xid and the call direction. We can use this
+ * to figure out if this is a call or a reply to a callback. If
+ * sk_reclen is < 8 (xid and calldir), then this is a malformed packet.
+ * In that case, don't bother with the calldir and just read the data.
+ * It will be rejected in svc_process.
+ */
+ if (len >= 8) {
+ len = svc_process_calldir(svsk, rqstp, &req, vec);
+ if (len < 0)
+ goto err_again;
+ vlen -= 8;
+ }
+
pnum = 1;
while (vlen < len) {
- vec[pnum].iov_base = page_address(rqstp->rq_pages[pnum]);
+ vec[pnum].iov_base = (req) ?
+ page_address(req->rq_private_buf.pages[pnum - 1]) :
+ page_address(rqstp->rq_pages[pnum]);
vec[pnum].iov_len = PAGE_SIZE;
pnum++;
vlen += PAGE_SIZE;
@@ -989,6 +1080,16 @@
if (len < 0)
goto err_again;
+ /*
+ * Account for the 8 bytes we read earlier
+ */
+ len += 8;
+
+ if (req) {
+ xprt_complete_rqst(req->rq_task, len);
+ len = 0;
+ goto out;
+ }
dprintk("svc: TCP complete record (%d bytes)\n", len);
rqstp->rq_arg.len = len;
rqstp->rq_arg.page_base = 0;
@@ -1002,6 +1103,7 @@
rqstp->rq_xprt_ctxt = NULL;
rqstp->rq_prot = IPPROTO_TCP;
+out:
/* Reset TCP read info */
svsk->sk_reclen = 0;
svsk->sk_tcplen = 0;