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>
This commit is contained in:
Rahul Iyer 2009-09-10 17:32:28 +03:00 committed by J. Bruce Fields
parent 6951867b99
commit 4cfc7e6019
8 changed files with 303 additions and 39 deletions

View File

@ -65,6 +65,7 @@ struct svc_xprt {
size_t xpt_locallen; /* length of address */
struct sockaddr_storage xpt_remote; /* remote peer's address */
size_t xpt_remotelen; /* length of address */
struct rpc_wait_queue xpt_bc_pending; /* backchannel wait queue */
};
int svc_reg_xprt_class(struct svc_xprt_class *);

View File

@ -28,6 +28,7 @@ struct svc_sock {
/* private TCP part */
u32 sk_reclen; /* length of record */
u32 sk_tcplen; /* current read length */
struct rpc_xprt *sk_bc_xprt; /* NFSv4.1 backchannel xprt */
};
/*

View File

@ -179,6 +179,7 @@ struct rpc_xprt {
spinlock_t reserve_lock; /* lock slot table */
u32 xid; /* Next XID value to use */
struct rpc_task * snd_task; /* Task blocked in send */
struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */
#if defined(CONFIG_NFS_V4_1)
struct svc_serv *bc_serv; /* The RPC service which will */
/* process the callback */

View File

@ -43,5 +43,9 @@ static inline int rpc_reply_expected(struct rpc_task *task)
(task->tk_msg.rpc_proc->p_decode != NULL);
}
int svc_send_common(struct socket *sock, struct xdr_buf *xdr,
struct page *headpage, unsigned long headoffset,
struct page *tailpage, unsigned long tailoffset);
#endif /* _NET_SUNRPC_SUNRPC_H */

View File

@ -160,6 +160,7 @@ void svc_xprt_init(struct svc_xprt_class *xcl, struct svc_xprt *xprt,
mutex_init(&xprt->xpt_mutex);
spin_lock_init(&xprt->xpt_lock);
set_bit(XPT_BUSY, &xprt->xpt_flags);
rpc_init_wait_queue(&xprt->xpt_bc_pending, "xpt_bc_pending");
}
EXPORT_SYMBOL_GPL(svc_xprt_init);
@ -810,6 +811,7 @@ int svc_send(struct svc_rqst *rqstp)
else
len = xprt->xpt_ops->xpo_sendto(rqstp);
mutex_unlock(&xprt->xpt_mutex);
rpc_wake_up(&xprt->xpt_bc_pending);
svc_xprt_release(rqstp);
if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN)

View File

@ -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 @@ static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
}
/*
* 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 @@ static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
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 @@ static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
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 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
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 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
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 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
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 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
rqstp->rq_xprt_ctxt = NULL;
rqstp->rq_prot = IPPROTO_TCP;
out:
/* Reset TCP read info */
svsk->sk_reclen = 0;
svsk->sk_tcplen = 0;

View File

@ -832,6 +832,11 @@ static void xprt_timer(struct rpc_task *task)
spin_unlock_bh(&xprt->transport_lock);
}
static inline int xprt_has_timer(struct rpc_xprt *xprt)
{
return xprt->idle_timeout != 0;
}
/**
* xprt_prepare_transmit - reserve the transport before sending a request
* @task: RPC task about to send a request
@ -1013,7 +1018,7 @@ void xprt_release(struct rpc_task *task)
if (!list_empty(&req->rq_list))
list_del(&req->rq_list);
xprt->last_used = jiffies;
if (list_empty(&xprt->recv))
if (list_empty(&xprt->recv) && xprt_has_timer(xprt))
mod_timer(&xprt->timer,
xprt->last_used + xprt->idle_timeout);
spin_unlock_bh(&xprt->transport_lock);
@ -1082,8 +1087,11 @@ found:
#endif /* CONFIG_NFS_V4_1 */
INIT_WORK(&xprt->task_cleanup, xprt_autoclose);
setup_timer(&xprt->timer, xprt_init_autodisconnect,
(unsigned long)xprt);
if (xprt_has_timer(xprt))
setup_timer(&xprt->timer, xprt_init_autodisconnect,
(unsigned long)xprt);
else
init_timer(&xprt->timer);
xprt->last_used = jiffies;
xprt->cwnd = RPC_INITCWND;
xprt->bind_index = 0;
@ -1102,7 +1110,6 @@ found:
dprintk("RPC: created transport %p with %u slots\n", xprt,
xprt->max_reqs);
return xprt;
}

View File

@ -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 @@ static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
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 @@ static struct rpc_xprt_ops xs_tcp_ops = {
.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)
{