2 * linux/net/sunrpc/xprtsock.c
4 * Client-side transport implementation for sockets.
6 * TCP callback races fixes (C) 1998 Red Hat Software <alan@redhat.com>
7 * TCP send fixes (C) 1998 Red Hat Software <alan@redhat.com>
8 * TCP NFS related read + write fixes
9 * (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
11 * Rewrite of larges part of the code in order to stabilize TCP stuff.
12 * Fix behaviour when socket buffer is full.
13 * (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
15 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
18 #include <linux/types.h>
19 #include <linux/slab.h>
20 #include <linux/capability.h>
21 #include <linux/sched.h>
22 #include <linux/pagemap.h>
23 #include <linux/errno.h>
24 #include <linux/socket.h>
26 #include <linux/net.h>
28 #include <linux/udp.h>
29 #include <linux/tcp.h>
30 #include <linux/sunrpc/clnt.h>
31 #include <linux/sunrpc/sched.h>
32 #include <linux/file.h>
35 #include <net/checksum.h>
42 unsigned int xprt_udp_slot_table_entries
= RPC_DEF_SLOT_TABLE
;
43 unsigned int xprt_tcp_slot_table_entries
= RPC_DEF_SLOT_TABLE
;
45 unsigned int xprt_min_resvport
= RPC_DEF_MIN_RESVPORT
;
46 unsigned int xprt_max_resvport
= RPC_DEF_MAX_RESVPORT
;
49 * How many times to try sending a request on a socket before waiting
50 * for the socket buffer to clear.
52 #define XS_SENDMSG_RETRY (10U)
55 * Time out for an RPC UDP socket connect. UDP socket connects are
56 * synchronous, but we set a timeout anyway in case of resource
57 * exhaustion on the local host.
59 #define XS_UDP_CONN_TO (5U * HZ)
62 * Wait duration for an RPC TCP connection to be established. Solaris
63 * NFS over TCP uses 60 seconds, for example, which is in line with how
64 * long a server takes to reboot.
66 #define XS_TCP_CONN_TO (60U * HZ)
69 * Wait duration for a reply from the RPC portmapper.
71 #define XS_BIND_TO (60U * HZ)
74 * Delay if a UDP socket connect error occurs. This is most likely some
75 * kind of resource problem on the local host.
77 #define XS_UDP_REEST_TO (2U * HZ)
80 * The reestablish timeout allows clients to delay for a bit before attempting
81 * to reconnect to a server that just dropped our connection.
83 * We implement an exponential backoff when trying to reestablish a TCP
84 * transport connection with the server. Some servers like to drop a TCP
85 * connection when they are overworked, so we start with a short timeout and
86 * increase over time if the server is down or not responding.
88 #define XS_TCP_INIT_REEST_TO (3U * HZ)
89 #define XS_TCP_MAX_REEST_TO (5U * 60 * HZ)
92 * TCP idle timeout; client drops the transport socket if it is idle
93 * for this long. Note that we also timeout UDP sockets to prevent
94 * holding port numbers when there is no RPC traffic.
96 #define XS_IDLE_DISC_TO (5U * 60 * HZ)
99 # undef RPC_DEBUG_DATA
100 # define RPCDBG_FACILITY RPCDBG_TRANS
103 #ifdef RPC_DEBUG_DATA
104 static void xs_pktdump(char *msg
, u32
*packet
, unsigned int count
)
106 u8
*buf
= (u8
*) packet
;
109 dprintk("RPC: %s\n", msg
);
110 for (j
= 0; j
< count
&& j
< 128; j
+= 4) {
114 dprintk("0x%04x ", j
);
116 dprintk("%02x%02x%02x%02x ",
117 buf
[j
], buf
[j
+1], buf
[j
+2], buf
[j
+3]);
122 static inline void xs_pktdump(char *msg
, u32
*packet
, unsigned int count
)
129 struct rpc_xprt xprt
;
134 struct socket
* sock
;
138 * State of TCP reply receive
146 unsigned long tcp_copied
,
150 static void xs_format_peer_addresses(struct rpc_xprt
*xprt
)
152 struct sockaddr_in
*addr
= (struct sockaddr_in
*) &xprt
->addr
;
155 buf
= kzalloc(20, GFP_KERNEL
);
157 snprintf(buf
, 20, "%u.%u.%u.%u",
158 NIPQUAD(addr
->sin_addr
.s_addr
));
160 xprt
->address_strings
[RPC_DISPLAY_ADDR
] = buf
;
162 buf
= kzalloc(8, GFP_KERNEL
);
164 snprintf(buf
, 8, "%u",
165 ntohs(addr
->sin_port
));
167 xprt
->address_strings
[RPC_DISPLAY_PORT
] = buf
;
169 if (xprt
->prot
== IPPROTO_UDP
)
170 xprt
->address_strings
[RPC_DISPLAY_PROTO
] = "udp";
172 xprt
->address_strings
[RPC_DISPLAY_PROTO
] = "tcp";
174 buf
= kzalloc(48, GFP_KERNEL
);
176 snprintf(buf
, 48, "addr=%u.%u.%u.%u port=%u proto=%s",
177 NIPQUAD(addr
->sin_addr
.s_addr
),
178 ntohs(addr
->sin_port
),
179 xprt
->prot
== IPPROTO_UDP
? "udp" : "tcp");
181 xprt
->address_strings
[RPC_DISPLAY_ALL
] = buf
;
184 static void xs_free_peer_addresses(struct rpc_xprt
*xprt
)
186 kfree(xprt
->address_strings
[RPC_DISPLAY_ADDR
]);
187 kfree(xprt
->address_strings
[RPC_DISPLAY_PORT
]);
188 kfree(xprt
->address_strings
[RPC_DISPLAY_ALL
]);
191 #define XS_SENDMSG_FLAGS (MSG_DONTWAIT | MSG_NOSIGNAL)
193 static int xs_send_kvec(struct socket
*sock
, struct sockaddr
*addr
, int addrlen
, struct kvec
*vec
, unsigned int base
, int more
)
195 struct msghdr msg
= {
197 .msg_namelen
= addrlen
,
198 .msg_flags
= XS_SENDMSG_FLAGS
| (more
? MSG_MORE
: 0),
201 .iov_base
= vec
->iov_base
+ base
,
202 .iov_len
= vec
->iov_len
- base
,
205 if (iov
.iov_len
!= 0)
206 return kernel_sendmsg(sock
, &msg
, &iov
, 1, iov
.iov_len
);
207 return kernel_sendmsg(sock
, &msg
, NULL
, 0, 0);
210 static int xs_send_pagedata(struct socket
*sock
, struct xdr_buf
*xdr
, unsigned int base
, int more
)
213 unsigned int remainder
;
216 remainder
= xdr
->page_len
- base
;
217 base
+= xdr
->page_base
;
218 ppage
= xdr
->pages
+ (base
>> PAGE_SHIFT
);
221 unsigned int len
= min_t(unsigned int, PAGE_SIZE
- base
, remainder
);
222 int flags
= XS_SENDMSG_FLAGS
;
225 if (remainder
!= 0 || more
)
227 err
= sock
->ops
->sendpage(sock
, *ppage
, base
, len
, flags
);
228 if (remainder
== 0 || err
!= len
)
242 * xs_sendpages - write pages directly to a socket
243 * @sock: socket to send on
244 * @addr: UDP only -- address of destination
245 * @addrlen: UDP only -- length of destination address
246 * @xdr: buffer containing this request
247 * @base: starting position in the buffer
250 static int xs_sendpages(struct socket
*sock
, struct sockaddr
*addr
, int addrlen
, struct xdr_buf
*xdr
, unsigned int base
)
252 unsigned int remainder
= xdr
->len
- base
;
258 clear_bit(SOCK_ASYNC_NOSPACE
, &sock
->flags
);
264 if (base
< xdr
->head
[0].iov_len
|| addr
!= NULL
) {
265 unsigned int len
= xdr
->head
[0].iov_len
- base
;
267 err
= xs_send_kvec(sock
, addr
, addrlen
, &xdr
->head
[0], base
, remainder
!= 0);
268 if (remainder
== 0 || err
!= len
)
273 base
-= xdr
->head
[0].iov_len
;
275 if (base
< xdr
->page_len
) {
276 unsigned int len
= xdr
->page_len
- base
;
278 err
= xs_send_pagedata(sock
, xdr
, base
, remainder
!= 0);
279 if (remainder
== 0 || err
!= len
)
284 base
-= xdr
->page_len
;
286 if (base
>= xdr
->tail
[0].iov_len
)
288 err
= xs_send_kvec(sock
, NULL
, 0, &xdr
->tail
[0], base
, 0);
298 * xs_nospace - place task on wait queue if transmit was incomplete
299 * @task: task to put to sleep
302 static void xs_nospace(struct rpc_task
*task
)
304 struct rpc_rqst
*req
= task
->tk_rqstp
;
305 struct rpc_xprt
*xprt
= req
->rq_xprt
;
306 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
308 dprintk("RPC: %4d xmit incomplete (%u left of %u)\n",
309 task
->tk_pid
, req
->rq_slen
- req
->rq_bytes_sent
,
312 if (test_bit(SOCK_ASYNC_NOSPACE
, &transport
->sock
->flags
)) {
313 /* Protect against races with write_space */
314 spin_lock_bh(&xprt
->transport_lock
);
316 /* Don't race with disconnect */
317 if (!xprt_connected(xprt
))
318 task
->tk_status
= -ENOTCONN
;
319 else if (test_bit(SOCK_NOSPACE
, &transport
->sock
->flags
))
320 xprt_wait_for_buffer_space(task
);
322 spin_unlock_bh(&xprt
->transport_lock
);
324 /* Keep holding the socket if it is blocked */
325 rpc_delay(task
, HZ
>>4);
329 * xs_udp_send_request - write an RPC request to a UDP socket
330 * @task: address of RPC task that manages the state of an RPC request
333 * 0: The request has been sent
334 * EAGAIN: The socket was blocked, please call again later to
335 * complete the request
336 * ENOTCONN: Caller needs to invoke connect logic then call again
337 * other: Some other error occured, the request was not sent
339 static int xs_udp_send_request(struct rpc_task
*task
)
341 struct rpc_rqst
*req
= task
->tk_rqstp
;
342 struct rpc_xprt
*xprt
= req
->rq_xprt
;
343 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
344 struct xdr_buf
*xdr
= &req
->rq_snd_buf
;
347 xs_pktdump("packet data:",
348 req
->rq_svec
->iov_base
,
349 req
->rq_svec
->iov_len
);
351 req
->rq_xtime
= jiffies
;
352 status
= xs_sendpages(transport
->sock
,
353 (struct sockaddr
*) &xprt
->addr
,
357 dprintk("RPC: xs_udp_send_request(%u) = %d\n",
358 xdr
->len
- req
->rq_bytes_sent
, status
);
360 if (likely(status
>= (int) req
->rq_slen
))
363 /* Still some bytes left; set up for a retry later. */
371 /* When the server has died, an ICMP port unreachable message
372 * prompts ECONNREFUSED. */
378 dprintk("RPC: sendmsg returned unrecognized error %d\n",
386 static inline void xs_encode_tcp_record_marker(struct xdr_buf
*buf
)
388 u32 reclen
= buf
->len
- sizeof(rpc_fraghdr
);
389 rpc_fraghdr
*base
= buf
->head
[0].iov_base
;
390 *base
= htonl(RPC_LAST_STREAM_FRAGMENT
| reclen
);
394 * xs_tcp_send_request - write an RPC request to a TCP socket
395 * @task: address of RPC task that manages the state of an RPC request
398 * 0: The request has been sent
399 * EAGAIN: The socket was blocked, please call again later to
400 * complete the request
401 * ENOTCONN: Caller needs to invoke connect logic then call again
402 * other: Some other error occured, the request was not sent
404 * XXX: In the case of soft timeouts, should we eventually give up
405 * if sendmsg is not able to make progress?
407 static int xs_tcp_send_request(struct rpc_task
*task
)
409 struct rpc_rqst
*req
= task
->tk_rqstp
;
410 struct rpc_xprt
*xprt
= req
->rq_xprt
;
411 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
412 struct xdr_buf
*xdr
= &req
->rq_snd_buf
;
413 int status
, retry
= 0;
415 xs_encode_tcp_record_marker(&req
->rq_snd_buf
);
417 xs_pktdump("packet data:",
418 req
->rq_svec
->iov_base
,
419 req
->rq_svec
->iov_len
);
421 /* Continue transmitting the packet/record. We must be careful
422 * to cope with writespace callbacks arriving _after_ we have
423 * called sendmsg(). */
425 req
->rq_xtime
= jiffies
;
426 status
= xs_sendpages(transport
->sock
,
427 NULL
, 0, xdr
, req
->rq_bytes_sent
);
429 dprintk("RPC: xs_tcp_send_request(%u) = %d\n",
430 xdr
->len
- req
->rq_bytes_sent
, status
);
432 if (unlikely(status
< 0))
435 /* If we've sent the entire packet, immediately
436 * reset the count of bytes sent. */
437 req
->rq_bytes_sent
+= status
;
438 task
->tk_bytes_sent
+= status
;
439 if (likely(req
->rq_bytes_sent
>= req
->rq_slen
)) {
440 req
->rq_bytes_sent
= 0;
445 if (retry
++ > XS_SENDMSG_RETRY
)
460 dprintk("RPC: sendmsg returned unrecognized error %d\n",
462 xprt_disconnect(xprt
);
470 * xs_tcp_release_xprt - clean up after a tcp transmission
474 * This cleans up if an error causes us to abort the transmission of a request.
475 * In this case, the socket may need to be reset in order to avoid confusing
478 static void xs_tcp_release_xprt(struct rpc_xprt
*xprt
, struct rpc_task
*task
)
480 struct rpc_rqst
*req
;
482 if (task
!= xprt
->snd_task
)
486 req
= task
->tk_rqstp
;
487 if (req
->rq_bytes_sent
== 0)
489 if (req
->rq_bytes_sent
== req
->rq_snd_buf
.len
)
491 set_bit(XPRT_CLOSE_WAIT
, &task
->tk_xprt
->state
);
493 xprt_release_xprt(xprt
, task
);
497 * xs_close - close a socket
500 * This is used when all requests are complete; ie, no DRC state remains
501 * on the server we want to save.
503 static void xs_close(struct rpc_xprt
*xprt
)
505 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
506 struct socket
*sock
= transport
->sock
;
507 struct sock
*sk
= transport
->inet
;
510 goto clear_close_wait
;
512 dprintk("RPC: xs_close xprt %p\n", xprt
);
514 write_lock_bh(&sk
->sk_callback_lock
);
515 transport
->inet
= NULL
;
516 transport
->sock
= NULL
;
518 sk
->sk_user_data
= NULL
;
519 sk
->sk_data_ready
= xprt
->old_data_ready
;
520 sk
->sk_state_change
= xprt
->old_state_change
;
521 sk
->sk_write_space
= xprt
->old_write_space
;
522 write_unlock_bh(&sk
->sk_callback_lock
);
528 smp_mb__before_clear_bit();
529 clear_bit(XPRT_CLOSE_WAIT
, &xprt
->state
);
530 smp_mb__after_clear_bit();
534 * xs_destroy - prepare to shutdown a transport
535 * @xprt: doomed transport
538 static void xs_destroy(struct rpc_xprt
*xprt
)
540 dprintk("RPC: xs_destroy xprt %p\n", xprt
);
542 cancel_delayed_work(&xprt
->connect_worker
);
543 flush_scheduled_work();
545 xprt_disconnect(xprt
);
547 xs_free_peer_addresses(xprt
);
552 static inline struct rpc_xprt
*xprt_from_sock(struct sock
*sk
)
554 return (struct rpc_xprt
*) sk
->sk_user_data
;
558 * xs_udp_data_ready - "data ready" callback for UDP sockets
559 * @sk: socket with data to read
560 * @len: how much data to read
563 static void xs_udp_data_ready(struct sock
*sk
, int len
)
565 struct rpc_task
*task
;
566 struct rpc_xprt
*xprt
;
567 struct rpc_rqst
*rovr
;
569 int err
, repsize
, copied
;
573 read_lock(&sk
->sk_callback_lock
);
574 dprintk("RPC: xs_udp_data_ready...\n");
575 if (!(xprt
= xprt_from_sock(sk
)))
578 if ((skb
= skb_recv_datagram(sk
, 0, 1, &err
)) == NULL
)
584 repsize
= skb
->len
- sizeof(struct udphdr
);
586 dprintk("RPC: impossible RPC reply size %d!\n", repsize
);
590 /* Copy the XID from the skb... */
591 xp
= skb_header_pointer(skb
, sizeof(struct udphdr
),
592 sizeof(_xid
), &_xid
);
596 /* Look up and lock the request corresponding to the given XID */
597 spin_lock(&xprt
->transport_lock
);
598 rovr
= xprt_lookup_rqst(xprt
, *xp
);
601 task
= rovr
->rq_task
;
603 if ((copied
= rovr
->rq_private_buf
.buflen
) > repsize
)
606 /* Suck it into the iovec, verify checksum if not done by hw. */
607 if (csum_partial_copy_to_xdr(&rovr
->rq_private_buf
, skb
))
610 /* Something worked... */
611 dst_confirm(skb
->dst
);
613 xprt_adjust_cwnd(task
, copied
);
614 xprt_update_rtt(task
);
615 xprt_complete_rqst(task
, copied
);
618 spin_unlock(&xprt
->transport_lock
);
620 skb_free_datagram(sk
, skb
);
622 read_unlock(&sk
->sk_callback_lock
);
625 static inline size_t xs_tcp_copy_data(skb_reader_t
*desc
, void *p
, size_t len
)
627 if (len
> desc
->count
)
629 if (skb_copy_bits(desc
->skb
, desc
->offset
, p
, len
)) {
630 dprintk("RPC: failed to copy %zu bytes from skb. %zu bytes remain\n",
636 dprintk("RPC: copied %zu bytes from skb. %zu bytes remain\n",
641 static inline void xs_tcp_read_fraghdr(struct rpc_xprt
*xprt
, skb_reader_t
*desc
)
643 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
647 p
= ((char *) &transport
->tcp_fraghdr
) + transport
->tcp_offset
;
648 len
= sizeof(transport
->tcp_fraghdr
) - transport
->tcp_offset
;
649 used
= xs_tcp_copy_data(desc
, p
, len
);
650 transport
->tcp_offset
+= used
;
654 transport
->tcp_reclen
= ntohl(transport
->tcp_fraghdr
);
655 if (transport
->tcp_reclen
& RPC_LAST_STREAM_FRAGMENT
)
656 transport
->tcp_flags
|= XPRT_LAST_FRAG
;
658 transport
->tcp_flags
&= ~XPRT_LAST_FRAG
;
659 transport
->tcp_reclen
&= RPC_FRAGMENT_SIZE_MASK
;
661 transport
->tcp_flags
&= ~XPRT_COPY_RECM
;
662 transport
->tcp_offset
= 0;
664 /* Sanity check of the record length */
665 if (unlikely(transport
->tcp_reclen
< 4)) {
666 dprintk("RPC: invalid TCP record fragment length\n");
667 xprt_disconnect(xprt
);
670 dprintk("RPC: reading TCP record fragment of length %d\n",
671 transport
->tcp_reclen
);
674 static void xs_tcp_check_fraghdr(struct sock_xprt
*transport
)
676 if (transport
->tcp_offset
== transport
->tcp_reclen
) {
677 transport
->tcp_flags
|= XPRT_COPY_RECM
;
678 transport
->tcp_offset
= 0;
679 if (transport
->tcp_flags
& XPRT_LAST_FRAG
) {
680 transport
->tcp_flags
&= ~XPRT_COPY_DATA
;
681 transport
->tcp_flags
|= XPRT_COPY_XID
;
682 transport
->tcp_copied
= 0;
687 static inline void xs_tcp_read_xid(struct sock_xprt
*transport
, skb_reader_t
*desc
)
692 len
= sizeof(transport
->tcp_xid
) - transport
->tcp_offset
;
693 dprintk("RPC: reading XID (%Zu bytes)\n", len
);
694 p
= ((char *) &transport
->tcp_xid
) + transport
->tcp_offset
;
695 used
= xs_tcp_copy_data(desc
, p
, len
);
696 transport
->tcp_offset
+= used
;
699 transport
->tcp_flags
&= ~XPRT_COPY_XID
;
700 transport
->tcp_flags
|= XPRT_COPY_DATA
;
701 transport
->tcp_copied
= 4;
702 dprintk("RPC: reading reply for XID %08x\n",
703 ntohl(transport
->tcp_xid
));
704 xs_tcp_check_fraghdr(transport
);
707 static inline void xs_tcp_read_request(struct rpc_xprt
*xprt
, skb_reader_t
*desc
)
709 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
710 struct rpc_rqst
*req
;
711 struct xdr_buf
*rcvbuf
;
715 /* Find and lock the request corresponding to this xid */
716 spin_lock(&xprt
->transport_lock
);
717 req
= xprt_lookup_rqst(xprt
, transport
->tcp_xid
);
719 transport
->tcp_flags
&= ~XPRT_COPY_DATA
;
720 dprintk("RPC: XID %08x request not found!\n",
721 ntohl(transport
->tcp_xid
));
722 spin_unlock(&xprt
->transport_lock
);
726 rcvbuf
= &req
->rq_private_buf
;
728 if (len
> transport
->tcp_reclen
- transport
->tcp_offset
) {
729 skb_reader_t my_desc
;
731 len
= transport
->tcp_reclen
- transport
->tcp_offset
;
732 memcpy(&my_desc
, desc
, sizeof(my_desc
));
734 r
= xdr_partial_copy_from_skb(rcvbuf
, transport
->tcp_copied
,
735 &my_desc
, xs_tcp_copy_data
);
739 r
= xdr_partial_copy_from_skb(rcvbuf
, transport
->tcp_copied
,
740 desc
, xs_tcp_copy_data
);
743 transport
->tcp_copied
+= r
;
744 transport
->tcp_offset
+= r
;
747 /* Error when copying to the receive buffer,
748 * usually because we weren't able to allocate
749 * additional buffer pages. All we can do now
750 * is turn off XPRT_COPY_DATA, so the request
751 * will not receive any additional updates,
753 * Any remaining data from this record will
756 transport
->tcp_flags
&= ~XPRT_COPY_DATA
;
757 dprintk("RPC: XID %08x truncated request\n",
758 ntohl(transport
->tcp_xid
));
759 dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n",
760 xprt
, transport
->tcp_copied
, transport
->tcp_offset
,
761 transport
->tcp_reclen
);
765 dprintk("RPC: XID %08x read %Zd bytes\n",
766 ntohl(transport
->tcp_xid
), r
);
767 dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n",
768 xprt
, transport
->tcp_copied
, transport
->tcp_offset
,
769 transport
->tcp_reclen
);
771 if (transport
->tcp_copied
== req
->rq_private_buf
.buflen
)
772 transport
->tcp_flags
&= ~XPRT_COPY_DATA
;
773 else if (transport
->tcp_offset
== transport
->tcp_reclen
) {
774 if (transport
->tcp_flags
& XPRT_LAST_FRAG
)
775 transport
->tcp_flags
&= ~XPRT_COPY_DATA
;
779 if (!(transport
->tcp_flags
& XPRT_COPY_DATA
))
780 xprt_complete_rqst(req
->rq_task
, transport
->tcp_copied
);
781 spin_unlock(&xprt
->transport_lock
);
782 xs_tcp_check_fraghdr(transport
);
785 static inline void xs_tcp_read_discard(struct sock_xprt
*transport
, skb_reader_t
*desc
)
789 len
= transport
->tcp_reclen
- transport
->tcp_offset
;
790 if (len
> desc
->count
)
794 transport
->tcp_offset
+= len
;
795 dprintk("RPC: discarded %Zu bytes\n", len
);
796 xs_tcp_check_fraghdr(transport
);
799 static int xs_tcp_data_recv(read_descriptor_t
*rd_desc
, struct sk_buff
*skb
, unsigned int offset
, size_t len
)
801 struct rpc_xprt
*xprt
= rd_desc
->arg
.data
;
802 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
803 skb_reader_t desc
= {
809 dprintk("RPC: xs_tcp_data_recv started\n");
811 /* Read in a new fragment marker if necessary */
812 /* Can we ever really expect to get completely empty fragments? */
813 if (transport
->tcp_flags
& XPRT_COPY_RECM
) {
814 xs_tcp_read_fraghdr(xprt
, &desc
);
817 /* Read in the xid if necessary */
818 if (transport
->tcp_flags
& XPRT_COPY_XID
) {
819 xs_tcp_read_xid(transport
, &desc
);
822 /* Read in the request data */
823 if (transport
->tcp_flags
& XPRT_COPY_DATA
) {
824 xs_tcp_read_request(xprt
, &desc
);
827 /* Skip over any trailing bytes on short reads */
828 xs_tcp_read_discard(transport
, &desc
);
829 } while (desc
.count
);
830 dprintk("RPC: xs_tcp_data_recv done\n");
831 return len
- desc
.count
;
835 * xs_tcp_data_ready - "data ready" callback for TCP sockets
836 * @sk: socket with data to read
837 * @bytes: how much data to read
840 static void xs_tcp_data_ready(struct sock
*sk
, int bytes
)
842 struct rpc_xprt
*xprt
;
843 read_descriptor_t rd_desc
;
845 read_lock(&sk
->sk_callback_lock
);
846 dprintk("RPC: xs_tcp_data_ready...\n");
847 if (!(xprt
= xprt_from_sock(sk
)))
852 /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
853 rd_desc
.arg
.data
= xprt
;
854 rd_desc
.count
= 65536;
855 tcp_read_sock(sk
, &rd_desc
, xs_tcp_data_recv
);
857 read_unlock(&sk
->sk_callback_lock
);
861 * xs_tcp_state_change - callback to handle TCP socket state changes
862 * @sk: socket whose state has changed
865 static void xs_tcp_state_change(struct sock
*sk
)
867 struct rpc_xprt
*xprt
;
869 read_lock(&sk
->sk_callback_lock
);
870 if (!(xprt
= xprt_from_sock(sk
)))
872 dprintk("RPC: xs_tcp_state_change client %p...\n", xprt
);
873 dprintk("RPC: state %x conn %d dead %d zapped %d\n",
874 sk
->sk_state
, xprt_connected(xprt
),
875 sock_flag(sk
, SOCK_DEAD
),
876 sock_flag(sk
, SOCK_ZAPPED
));
878 switch (sk
->sk_state
) {
879 case TCP_ESTABLISHED
:
880 spin_lock_bh(&xprt
->transport_lock
);
881 if (!xprt_test_and_set_connected(xprt
)) {
882 struct sock_xprt
*transport
= container_of(xprt
,
883 struct sock_xprt
, xprt
);
885 /* Reset TCP record info */
886 transport
->tcp_offset
= 0;
887 transport
->tcp_reclen
= 0;
888 transport
->tcp_copied
= 0;
889 transport
->tcp_flags
= XPRT_COPY_RECM
| XPRT_COPY_XID
;
891 xprt
->reestablish_timeout
= XS_TCP_INIT_REEST_TO
;
892 xprt_wake_pending_tasks(xprt
, 0);
894 spin_unlock_bh(&xprt
->transport_lock
);
900 /* Try to schedule an autoclose RPC calls */
901 set_bit(XPRT_CLOSE_WAIT
, &xprt
->state
);
902 if (test_and_set_bit(XPRT_LOCKED
, &xprt
->state
) == 0)
903 schedule_work(&xprt
->task_cleanup
);
905 xprt_disconnect(xprt
);
908 read_unlock(&sk
->sk_callback_lock
);
912 * xs_udp_write_space - callback invoked when socket buffer space
914 * @sk: socket whose state has changed
916 * Called when more output buffer space is available for this socket.
917 * We try not to wake our writers until they can make "significant"
918 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
919 * with a bunch of small requests.
921 static void xs_udp_write_space(struct sock
*sk
)
923 read_lock(&sk
->sk_callback_lock
);
925 /* from net/core/sock.c:sock_def_write_space */
926 if (sock_writeable(sk
)) {
928 struct rpc_xprt
*xprt
;
930 if (unlikely(!(sock
= sk
->sk_socket
)))
932 if (unlikely(!(xprt
= xprt_from_sock(sk
))))
934 if (unlikely(!test_and_clear_bit(SOCK_NOSPACE
, &sock
->flags
)))
937 xprt_write_space(xprt
);
941 read_unlock(&sk
->sk_callback_lock
);
945 * xs_tcp_write_space - callback invoked when socket buffer space
947 * @sk: socket whose state has changed
949 * Called when more output buffer space is available for this socket.
950 * We try not to wake our writers until they can make "significant"
951 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
952 * with a bunch of small requests.
954 static void xs_tcp_write_space(struct sock
*sk
)
956 read_lock(&sk
->sk_callback_lock
);
958 /* from net/core/stream.c:sk_stream_write_space */
959 if (sk_stream_wspace(sk
) >= sk_stream_min_wspace(sk
)) {
961 struct rpc_xprt
*xprt
;
963 if (unlikely(!(sock
= sk
->sk_socket
)))
965 if (unlikely(!(xprt
= xprt_from_sock(sk
))))
967 if (unlikely(!test_and_clear_bit(SOCK_NOSPACE
, &sock
->flags
)))
970 xprt_write_space(xprt
);
974 read_unlock(&sk
->sk_callback_lock
);
977 static void xs_udp_do_set_buffer_size(struct rpc_xprt
*xprt
)
979 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
980 struct sock
*sk
= transport
->inet
;
983 sk
->sk_userlocks
|= SOCK_RCVBUF_LOCK
;
984 sk
->sk_rcvbuf
= xprt
->rcvsize
* xprt
->max_reqs
* 2;
987 sk
->sk_userlocks
|= SOCK_SNDBUF_LOCK
;
988 sk
->sk_sndbuf
= xprt
->sndsize
* xprt
->max_reqs
* 2;
989 sk
->sk_write_space(sk
);
994 * xs_udp_set_buffer_size - set send and receive limits
995 * @xprt: generic transport
996 * @sndsize: requested size of send buffer, in bytes
997 * @rcvsize: requested size of receive buffer, in bytes
999 * Set socket send and receive buffer size limits.
1001 static void xs_udp_set_buffer_size(struct rpc_xprt
*xprt
, size_t sndsize
, size_t rcvsize
)
1005 xprt
->sndsize
= sndsize
+ 1024;
1008 xprt
->rcvsize
= rcvsize
+ 1024;
1010 xs_udp_do_set_buffer_size(xprt
);
1014 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1015 * @task: task that timed out
1017 * Adjust the congestion window after a retransmit timeout has occurred.
1019 static void xs_udp_timer(struct rpc_task
*task
)
1021 xprt_adjust_cwnd(task
, -ETIMEDOUT
);
1024 static unsigned short xs_get_random_port(void)
1026 unsigned short range
= xprt_max_resvport
- xprt_min_resvport
;
1027 unsigned short rand
= (unsigned short) net_random() % range
;
1028 return rand
+ xprt_min_resvport
;
1032 * xs_print_peer_address - format an IPv4 address for printing
1033 * @xprt: generic transport
1034 * @format: flags field indicating which parts of the address to render
1036 static char *xs_print_peer_address(struct rpc_xprt
*xprt
, enum rpc_display_format_t format
)
1038 if (xprt
->address_strings
[format
] != NULL
)
1039 return xprt
->address_strings
[format
];
1041 return "unprintable";
1045 * xs_set_port - reset the port number in the remote endpoint address
1046 * @xprt: generic transport
1047 * @port: new port number
1050 static void xs_set_port(struct rpc_xprt
*xprt
, unsigned short port
)
1052 struct sockaddr_in
*sap
= (struct sockaddr_in
*) &xprt
->addr
;
1054 dprintk("RPC: setting port for xprt %p to %u\n", xprt
, port
);
1056 sap
->sin_port
= htons(port
);
1059 static int xs_bindresvport(struct rpc_xprt
*xprt
, struct socket
*sock
)
1061 struct sockaddr_in myaddr
= {
1062 .sin_family
= AF_INET
,
1065 unsigned short port
= xprt
->port
;
1068 myaddr
.sin_port
= htons(port
);
1069 err
= kernel_bind(sock
, (struct sockaddr
*) &myaddr
,
1073 dprintk("RPC: xs_bindresvport bound to port %u\n",
1077 if (port
<= xprt_min_resvport
)
1078 port
= xprt_max_resvport
;
1081 } while (err
== -EADDRINUSE
&& port
!= xprt
->port
);
1083 dprintk("RPC: can't bind to reserved port (%d).\n", -err
);
1088 * xs_udp_connect_worker - set up a UDP socket
1089 * @args: RPC transport to connect
1091 * Invoked by a work queue tasklet.
1093 static void xs_udp_connect_worker(void *args
)
1095 struct rpc_xprt
*xprt
= (struct rpc_xprt
*) args
;
1096 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
1097 struct socket
*sock
= transport
->sock
;
1098 int err
, status
= -EIO
;
1100 if (xprt
->shutdown
|| !xprt_bound(xprt
))
1103 /* Start by resetting any existing state */
1106 if ((err
= sock_create_kern(PF_INET
, SOCK_DGRAM
, IPPROTO_UDP
, &sock
)) < 0) {
1107 dprintk("RPC: can't create UDP transport socket (%d).\n", -err
);
1111 if (xprt
->resvport
&& xs_bindresvport(xprt
, sock
) < 0) {
1116 dprintk("RPC: worker connecting xprt %p to address: %s\n",
1117 xprt
, xs_print_peer_address(xprt
, RPC_DISPLAY_ALL
));
1119 if (!transport
->inet
) {
1120 struct sock
*sk
= sock
->sk
;
1122 write_lock_bh(&sk
->sk_callback_lock
);
1124 sk
->sk_user_data
= xprt
;
1125 xprt
->old_data_ready
= sk
->sk_data_ready
;
1126 xprt
->old_state_change
= sk
->sk_state_change
;
1127 xprt
->old_write_space
= sk
->sk_write_space
;
1128 sk
->sk_data_ready
= xs_udp_data_ready
;
1129 sk
->sk_write_space
= xs_udp_write_space
;
1130 sk
->sk_no_check
= UDP_CSUM_NORCV
;
1131 sk
->sk_allocation
= GFP_ATOMIC
;
1133 xprt_set_connected(xprt
);
1135 /* Reset to new socket */
1136 transport
->sock
= sock
;
1137 transport
->inet
= sk
;
1139 write_unlock_bh(&sk
->sk_callback_lock
);
1141 xs_udp_do_set_buffer_size(xprt
);
1144 xprt_wake_pending_tasks(xprt
, status
);
1145 xprt_clear_connecting(xprt
);
1149 * We need to preserve the port number so the reply cache on the server can
1150 * find our cached RPC replies when we get around to reconnecting.
1152 static void xs_tcp_reuse_connection(struct rpc_xprt
*xprt
)
1155 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
1156 struct sockaddr any
;
1158 dprintk("RPC: disconnecting xprt %p to reuse port\n", xprt
);
1161 * Disconnect the transport socket by doing a connect operation
1162 * with AF_UNSPEC. This should return immediately...
1164 memset(&any
, 0, sizeof(any
));
1165 any
.sa_family
= AF_UNSPEC
;
1166 result
= kernel_connect(transport
->sock
, &any
, sizeof(any
), 0);
1168 dprintk("RPC: AF_UNSPEC connect return code %d\n",
1173 * xs_tcp_connect_worker - connect a TCP socket to a remote endpoint
1174 * @args: RPC transport to connect
1176 * Invoked by a work queue tasklet.
1178 static void xs_tcp_connect_worker(void *args
)
1180 struct rpc_xprt
*xprt
= (struct rpc_xprt
*)args
;
1181 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
1182 struct socket
*sock
= transport
->sock
;
1183 int err
, status
= -EIO
;
1185 if (xprt
->shutdown
|| !xprt_bound(xprt
))
1189 /* start from scratch */
1190 if ((err
= sock_create_kern(PF_INET
, SOCK_STREAM
, IPPROTO_TCP
, &sock
)) < 0) {
1191 dprintk("RPC: can't create TCP transport socket (%d).\n", -err
);
1195 if (xprt
->resvport
&& xs_bindresvport(xprt
, sock
) < 0) {
1200 /* "close" the socket, preserving the local port */
1201 xs_tcp_reuse_connection(xprt
);
1203 dprintk("RPC: worker connecting xprt %p to address: %s\n",
1204 xprt
, xs_print_peer_address(xprt
, RPC_DISPLAY_ALL
));
1206 if (!transport
->inet
) {
1207 struct sock
*sk
= sock
->sk
;
1209 write_lock_bh(&sk
->sk_callback_lock
);
1211 sk
->sk_user_data
= xprt
;
1212 xprt
->old_data_ready
= sk
->sk_data_ready
;
1213 xprt
->old_state_change
= sk
->sk_state_change
;
1214 xprt
->old_write_space
= sk
->sk_write_space
;
1215 sk
->sk_data_ready
= xs_tcp_data_ready
;
1216 sk
->sk_state_change
= xs_tcp_state_change
;
1217 sk
->sk_write_space
= xs_tcp_write_space
;
1218 sk
->sk_allocation
= GFP_ATOMIC
;
1220 /* socket options */
1221 sk
->sk_userlocks
|= SOCK_BINDPORT_LOCK
;
1222 sock_reset_flag(sk
, SOCK_LINGER
);
1223 tcp_sk(sk
)->linger2
= 0;
1224 tcp_sk(sk
)->nonagle
|= TCP_NAGLE_OFF
;
1226 xprt_clear_connected(xprt
);
1228 /* Reset to new socket */
1229 transport
->sock
= sock
;
1230 transport
->inet
= sk
;
1232 write_unlock_bh(&sk
->sk_callback_lock
);
1235 /* Tell the socket layer to start connecting... */
1236 xprt
->stat
.connect_count
++;
1237 xprt
->stat
.connect_start
= jiffies
;
1238 status
= kernel_connect(sock
, (struct sockaddr
*) &xprt
->addr
,
1239 xprt
->addrlen
, O_NONBLOCK
);
1240 dprintk("RPC: %p connect status %d connected %d sock state %d\n",
1241 xprt
, -status
, xprt_connected(xprt
), sock
->sk
->sk_state
);
1249 /* retry with existing socket, after a delay */
1252 /* get rid of existing socket, and retry */
1258 xprt_wake_pending_tasks(xprt
, status
);
1260 xprt_clear_connecting(xprt
);
1264 * xs_connect - connect a socket to a remote endpoint
1265 * @task: address of RPC task that manages state of connect request
1267 * TCP: If the remote end dropped the connection, delay reconnecting.
1269 * UDP socket connects are synchronous, but we use a work queue anyway
1270 * to guarantee that even unprivileged user processes can set up a
1271 * socket on a privileged port.
1273 * If a UDP socket connect fails, the delay behavior here prevents
1274 * retry floods (hard mounts).
1276 static void xs_connect(struct rpc_task
*task
)
1278 struct rpc_xprt
*xprt
= task
->tk_xprt
;
1279 struct sock_xprt
*transport
= container_of(xprt
, struct sock_xprt
, xprt
);
1281 if (xprt_test_and_set_connecting(xprt
))
1284 if (transport
->sock
!= NULL
) {
1285 dprintk("RPC: xs_connect delayed xprt %p for %lu seconds\n",
1286 xprt
, xprt
->reestablish_timeout
/ HZ
);
1287 schedule_delayed_work(&xprt
->connect_worker
,
1288 xprt
->reestablish_timeout
);
1289 xprt
->reestablish_timeout
<<= 1;
1290 if (xprt
->reestablish_timeout
> XS_TCP_MAX_REEST_TO
)
1291 xprt
->reestablish_timeout
= XS_TCP_MAX_REEST_TO
;
1293 dprintk("RPC: xs_connect scheduled xprt %p\n", xprt
);
1294 schedule_work(&xprt
->connect_worker
);
1296 /* flush_scheduled_work can sleep... */
1297 if (!RPC_IS_ASYNC(task
))
1298 flush_scheduled_work();
1303 * xs_udp_print_stats - display UDP socket-specifc stats
1304 * @xprt: rpc_xprt struct containing statistics
1308 static void xs_udp_print_stats(struct rpc_xprt
*xprt
, struct seq_file
*seq
)
1310 seq_printf(seq
, "\txprt:\tudp %u %lu %lu %lu %lu %Lu %Lu\n",
1312 xprt
->stat
.bind_count
,
1315 xprt
->stat
.bad_xids
,
1317 xprt
->stat
.bklog_u
);
1321 * xs_tcp_print_stats - display TCP socket-specifc stats
1322 * @xprt: rpc_xprt struct containing statistics
1326 static void xs_tcp_print_stats(struct rpc_xprt
*xprt
, struct seq_file
*seq
)
1330 if (xprt_connected(xprt
))
1331 idle_time
= (long)(jiffies
- xprt
->last_used
) / HZ
;
1333 seq_printf(seq
, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu %Lu %Lu\n",
1335 xprt
->stat
.bind_count
,
1336 xprt
->stat
.connect_count
,
1337 xprt
->stat
.connect_time
,
1341 xprt
->stat
.bad_xids
,
1343 xprt
->stat
.bklog_u
);
1346 static struct rpc_xprt_ops xs_udp_ops
= {
1347 .set_buffer_size
= xs_udp_set_buffer_size
,
1348 .print_addr
= xs_print_peer_address
,
1349 .reserve_xprt
= xprt_reserve_xprt_cong
,
1350 .release_xprt
= xprt_release_xprt_cong
,
1351 .rpcbind
= rpc_getport
,
1352 .set_port
= xs_set_port
,
1353 .connect
= xs_connect
,
1354 .buf_alloc
= rpc_malloc
,
1355 .buf_free
= rpc_free
,
1356 .send_request
= xs_udp_send_request
,
1357 .set_retrans_timeout
= xprt_set_retrans_timeout_rtt
,
1358 .timer
= xs_udp_timer
,
1359 .release_request
= xprt_release_rqst_cong
,
1361 .destroy
= xs_destroy
,
1362 .print_stats
= xs_udp_print_stats
,
1365 static struct rpc_xprt_ops xs_tcp_ops
= {
1366 .print_addr
= xs_print_peer_address
,
1367 .reserve_xprt
= xprt_reserve_xprt
,
1368 .release_xprt
= xs_tcp_release_xprt
,
1369 .rpcbind
= rpc_getport
,
1370 .set_port
= xs_set_port
,
1371 .connect
= xs_connect
,
1372 .buf_alloc
= rpc_malloc
,
1373 .buf_free
= rpc_free
,
1374 .send_request
= xs_tcp_send_request
,
1375 .set_retrans_timeout
= xprt_set_retrans_timeout_def
,
1377 .destroy
= xs_destroy
,
1378 .print_stats
= xs_tcp_print_stats
,
1381 static struct rpc_xprt
*xs_setup_xprt(struct sockaddr
*addr
, size_t addrlen
, unsigned int slot_table_size
)
1383 struct rpc_xprt
*xprt
;
1384 struct sock_xprt
*new;
1386 if (addrlen
> sizeof(xprt
->addr
)) {
1387 dprintk("RPC: xs_setup_xprt: address too large\n");
1388 return ERR_PTR(-EBADF
);
1391 new = kzalloc(sizeof(*new), GFP_KERNEL
);
1393 dprintk("RPC: xs_setup_xprt: couldn't allocate rpc_xprt\n");
1394 return ERR_PTR(-ENOMEM
);
1398 xprt
->max_reqs
= slot_table_size
;
1399 xprt
->slot
= kcalloc(xprt
->max_reqs
, sizeof(struct rpc_rqst
), GFP_KERNEL
);
1400 if (xprt
->slot
== NULL
) {
1402 dprintk("RPC: xs_setup_xprt: couldn't allocate slot table\n");
1403 return ERR_PTR(-ENOMEM
);
1406 memcpy(&xprt
->addr
, addr
, addrlen
);
1407 xprt
->addrlen
= addrlen
;
1408 xprt
->port
= xs_get_random_port();
1414 * xs_setup_udp - Set up transport to use a UDP socket
1415 * @addr: address of remote server
1416 * @addrlen: length of address in bytes
1417 * @to: timeout parameters
1420 struct rpc_xprt
*xs_setup_udp(struct sockaddr
*addr
, size_t addrlen
, struct rpc_timeout
*to
)
1422 struct rpc_xprt
*xprt
;
1424 xprt
= xs_setup_xprt(addr
, addrlen
, xprt_udp_slot_table_entries
);
1428 if (ntohs(((struct sockaddr_in
*)addr
)->sin_port
) != 0)
1429 xprt_set_bound(xprt
);
1431 xprt
->prot
= IPPROTO_UDP
;
1433 /* XXX: header size can vary due to auth type, IPv6, etc. */
1434 xprt
->max_payload
= (1U << 16) - (MAX_HEADER
<< 3);
1436 INIT_WORK(&xprt
->connect_worker
, xs_udp_connect_worker
, xprt
);
1437 xprt
->bind_timeout
= XS_BIND_TO
;
1438 xprt
->connect_timeout
= XS_UDP_CONN_TO
;
1439 xprt
->reestablish_timeout
= XS_UDP_REEST_TO
;
1440 xprt
->idle_timeout
= XS_IDLE_DISC_TO
;
1442 xprt
->ops
= &xs_udp_ops
;
1445 xprt
->timeout
= *to
;
1447 xprt_set_timeout(&xprt
->timeout
, 5, 5 * HZ
);
1449 xs_format_peer_addresses(xprt
);
1450 dprintk("RPC: set up transport to address %s\n",
1451 xs_print_peer_address(xprt
, RPC_DISPLAY_ALL
));
1457 * xs_setup_tcp - Set up transport to use a TCP socket
1458 * @addr: address of remote server
1459 * @addrlen: length of address in bytes
1460 * @to: timeout parameters
1463 struct rpc_xprt
*xs_setup_tcp(struct sockaddr
*addr
, size_t addrlen
, struct rpc_timeout
*to
)
1465 struct rpc_xprt
*xprt
;
1467 xprt
= xs_setup_xprt(addr
, addrlen
, xprt_tcp_slot_table_entries
);
1471 if (ntohs(((struct sockaddr_in
*)addr
)->sin_port
) != 0)
1472 xprt_set_bound(xprt
);
1474 xprt
->prot
= IPPROTO_TCP
;
1475 xprt
->tsh_size
= sizeof(rpc_fraghdr
) / sizeof(u32
);
1476 xprt
->max_payload
= RPC_MAX_FRAGMENT_SIZE
;
1478 INIT_WORK(&xprt
->connect_worker
, xs_tcp_connect_worker
, xprt
);
1479 xprt
->bind_timeout
= XS_BIND_TO
;
1480 xprt
->connect_timeout
= XS_TCP_CONN_TO
;
1481 xprt
->reestablish_timeout
= XS_TCP_INIT_REEST_TO
;
1482 xprt
->idle_timeout
= XS_IDLE_DISC_TO
;
1484 xprt
->ops
= &xs_tcp_ops
;
1487 xprt
->timeout
= *to
;
1489 xprt_set_timeout(&xprt
->timeout
, 2, 60 * HZ
);
1491 xs_format_peer_addresses(xprt
);
1492 dprintk("RPC: set up transport to address %s\n",
1493 xs_print_peer_address(xprt
, RPC_DISPLAY_ALL
));