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/file.h>
34 #include <net/checksum.h>
41 unsigned int xprt_udp_slot_table_entries
= RPC_DEF_SLOT_TABLE
;
42 unsigned int xprt_tcp_slot_table_entries
= RPC_DEF_SLOT_TABLE
;
44 unsigned int xprt_min_resvport
= RPC_DEF_MIN_RESVPORT
;
45 unsigned int xprt_max_resvport
= RPC_DEF_MAX_RESVPORT
;
48 * How many times to try sending a request on a socket before waiting
49 * for the socket buffer to clear.
51 #define XS_SENDMSG_RETRY (10U)
54 * Time out for an RPC UDP socket connect. UDP socket connects are
55 * synchronous, but we set a timeout anyway in case of resource
56 * exhaustion on the local host.
58 #define XS_UDP_CONN_TO (5U * HZ)
61 * Wait duration for an RPC TCP connection to be established. Solaris
62 * NFS over TCP uses 60 seconds, for example, which is in line with how
63 * long a server takes to reboot.
65 #define XS_TCP_CONN_TO (60U * HZ)
68 * Wait duration for a reply from the RPC portmapper.
70 #define XS_BIND_TO (60U * HZ)
73 * Delay if a UDP socket connect error occurs. This is most likely some
74 * kind of resource problem on the local host.
76 #define XS_UDP_REEST_TO (2U * HZ)
79 * The reestablish timeout allows clients to delay for a bit before attempting
80 * to reconnect to a server that just dropped our connection.
82 * We implement an exponential backoff when trying to reestablish a TCP
83 * transport connection with the server. Some servers like to drop a TCP
84 * connection when they are overworked, so we start with a short timeout and
85 * increase over time if the server is down or not responding.
87 #define XS_TCP_INIT_REEST_TO (3U * HZ)
88 #define XS_TCP_MAX_REEST_TO (5U * 60 * HZ)
91 * TCP idle timeout; client drops the transport socket if it is idle
92 * for this long. Note that we also timeout UDP sockets to prevent
93 * holding port numbers when there is no RPC traffic.
95 #define XS_IDLE_DISC_TO (5U * 60 * HZ)
98 # undef RPC_DEBUG_DATA
99 # define RPCDBG_FACILITY RPCDBG_TRANS
102 #ifdef RPC_DEBUG_DATA
103 static void xs_pktdump(char *msg
, u32
*packet
, unsigned int count
)
105 u8
*buf
= (u8
*) packet
;
108 dprintk("RPC: %s\n", msg
);
109 for (j
= 0; j
< count
&& j
< 128; j
+= 4) {
113 dprintk("0x%04x ", j
);
115 dprintk("%02x%02x%02x%02x ",
116 buf
[j
], buf
[j
+1], buf
[j
+2], buf
[j
+3]);
121 static inline void xs_pktdump(char *msg
, u32
*packet
, unsigned int count
)
127 #define XS_SENDMSG_FLAGS (MSG_DONTWAIT | MSG_NOSIGNAL)
129 static inline int xs_send_head(struct socket
*sock
, struct sockaddr
*addr
, int addrlen
, struct xdr_buf
*xdr
, unsigned int base
, unsigned int len
)
132 .iov_base
= xdr
->head
[0].iov_base
+ base
,
133 .iov_len
= len
- base
,
135 struct msghdr msg
= {
137 .msg_namelen
= addrlen
,
138 .msg_flags
= XS_SENDMSG_FLAGS
,
142 msg
.msg_flags
|= MSG_MORE
;
144 if (likely(iov
.iov_len
))
145 return kernel_sendmsg(sock
, &msg
, &iov
, 1, iov
.iov_len
);
146 return kernel_sendmsg(sock
, &msg
, NULL
, 0, 0);
149 static int xs_send_tail(struct socket
*sock
, struct xdr_buf
*xdr
, unsigned int base
, unsigned int len
)
152 .iov_base
= xdr
->tail
[0].iov_base
+ base
,
153 .iov_len
= len
- base
,
155 struct msghdr msg
= {
156 .msg_flags
= XS_SENDMSG_FLAGS
,
159 return kernel_sendmsg(sock
, &msg
, &iov
, 1, iov
.iov_len
);
163 * xs_sendpages - write pages directly to a socket
164 * @sock: socket to send on
165 * @addr: UDP only -- address of destination
166 * @addrlen: UDP only -- length of destination address
167 * @xdr: buffer containing this request
168 * @base: starting position in the buffer
171 static inline int xs_sendpages(struct socket
*sock
, struct sockaddr
*addr
, int addrlen
, struct xdr_buf
*xdr
, unsigned int base
)
173 struct page
**ppage
= xdr
->pages
;
174 unsigned int len
, pglen
= xdr
->page_len
;
176 ssize_t (*sendpage
)(struct socket
*, struct page
*, int, size_t, int);
181 clear_bit(SOCK_ASYNC_NOSPACE
, &sock
->flags
);
183 len
= xdr
->head
[0].iov_len
;
184 if (base
< len
|| (addr
!= NULL
&& base
== 0)) {
185 err
= xs_send_head(sock
, addr
, addrlen
, xdr
, base
, len
);
190 if (err
!= (len
- base
))
196 if (unlikely(pglen
== 0))
198 if (unlikely(base
>= pglen
)) {
202 if (base
|| xdr
->page_base
) {
204 base
+= xdr
->page_base
;
205 ppage
+= base
>> PAGE_CACHE_SHIFT
;
206 base
&= ~PAGE_CACHE_MASK
;
209 sendpage
= sock
->ops
->sendpage
? : sock_no_sendpage
;
211 int flags
= XS_SENDMSG_FLAGS
;
213 len
= PAGE_CACHE_SIZE
;
219 if (pglen
!= len
|| xdr
->tail
[0].iov_len
!= 0)
222 /* Hmm... We might be dealing with highmem pages */
223 if (PageHighMem(*ppage
))
224 sendpage
= sock_no_sendpage
;
225 err
= sendpage(sock
, *ppage
, base
, len
, flags
);
234 } while ((pglen
-= len
) != 0);
236 len
= xdr
->tail
[0].iov_len
;
238 err
= xs_send_tail(sock
, xdr
, base
, len
);
249 * xs_nospace - place task on wait queue if transmit was incomplete
250 * @task: task to put to sleep
253 static void xs_nospace(struct rpc_task
*task
)
255 struct rpc_rqst
*req
= task
->tk_rqstp
;
256 struct rpc_xprt
*xprt
= req
->rq_xprt
;
258 dprintk("RPC: %4d xmit incomplete (%u left of %u)\n",
259 task
->tk_pid
, req
->rq_slen
- req
->rq_bytes_sent
,
262 if (test_bit(SOCK_ASYNC_NOSPACE
, &xprt
->sock
->flags
)) {
263 /* Protect against races with write_space */
264 spin_lock_bh(&xprt
->transport_lock
);
266 /* Don't race with disconnect */
267 if (!xprt_connected(xprt
))
268 task
->tk_status
= -ENOTCONN
;
269 else if (test_bit(SOCK_NOSPACE
, &xprt
->sock
->flags
))
270 xprt_wait_for_buffer_space(task
);
272 spin_unlock_bh(&xprt
->transport_lock
);
274 /* Keep holding the socket if it is blocked */
275 rpc_delay(task
, HZ
>>4);
279 * xs_udp_send_request - write an RPC request to a UDP socket
280 * @task: address of RPC task that manages the state of an RPC request
283 * 0: The request has been sent
284 * EAGAIN: The socket was blocked, please call again later to
285 * complete the request
286 * ENOTCONN: Caller needs to invoke connect logic then call again
287 * other: Some other error occured, the request was not sent
289 static int xs_udp_send_request(struct rpc_task
*task
)
291 struct rpc_rqst
*req
= task
->tk_rqstp
;
292 struct rpc_xprt
*xprt
= req
->rq_xprt
;
293 struct xdr_buf
*xdr
= &req
->rq_snd_buf
;
296 xs_pktdump("packet data:",
297 req
->rq_svec
->iov_base
,
298 req
->rq_svec
->iov_len
);
300 req
->rq_xtime
= jiffies
;
301 status
= xs_sendpages(xprt
->sock
, (struct sockaddr
*) &xprt
->addr
,
302 sizeof(xprt
->addr
), xdr
, req
->rq_bytes_sent
);
304 dprintk("RPC: xs_udp_send_request(%u) = %d\n",
305 xdr
->len
- req
->rq_bytes_sent
, status
);
307 if (likely(status
>= (int) req
->rq_slen
))
310 /* Still some bytes left; set up for a retry later. */
318 /* When the server has died, an ICMP port unreachable message
319 * prompts ECONNREFUSED. */
325 dprintk("RPC: sendmsg returned unrecognized error %d\n",
333 static inline void xs_encode_tcp_record_marker(struct xdr_buf
*buf
)
335 u32 reclen
= buf
->len
- sizeof(rpc_fraghdr
);
336 rpc_fraghdr
*base
= buf
->head
[0].iov_base
;
337 *base
= htonl(RPC_LAST_STREAM_FRAGMENT
| reclen
);
341 * xs_tcp_send_request - write an RPC request to a TCP socket
342 * @task: address of RPC task that manages the state of an RPC request
345 * 0: The request has been sent
346 * EAGAIN: The socket was blocked, please call again later to
347 * complete the request
348 * ENOTCONN: Caller needs to invoke connect logic then call again
349 * other: Some other error occured, the request was not sent
351 * XXX: In the case of soft timeouts, should we eventually give up
352 * if sendmsg is not able to make progress?
354 static int xs_tcp_send_request(struct rpc_task
*task
)
356 struct rpc_rqst
*req
= task
->tk_rqstp
;
357 struct rpc_xprt
*xprt
= req
->rq_xprt
;
358 struct xdr_buf
*xdr
= &req
->rq_snd_buf
;
359 int status
, retry
= 0;
361 xs_encode_tcp_record_marker(&req
->rq_snd_buf
);
363 xs_pktdump("packet data:",
364 req
->rq_svec
->iov_base
,
365 req
->rq_svec
->iov_len
);
367 /* Continue transmitting the packet/record. We must be careful
368 * to cope with writespace callbacks arriving _after_ we have
369 * called sendmsg(). */
371 req
->rq_xtime
= jiffies
;
372 status
= xs_sendpages(xprt
->sock
, NULL
, 0, xdr
,
375 dprintk("RPC: xs_tcp_send_request(%u) = %d\n",
376 xdr
->len
- req
->rq_bytes_sent
, status
);
378 if (unlikely(status
< 0))
381 /* If we've sent the entire packet, immediately
382 * reset the count of bytes sent. */
383 req
->rq_bytes_sent
+= status
;
384 if (likely(req
->rq_bytes_sent
>= req
->rq_slen
)) {
385 req
->rq_bytes_sent
= 0;
390 if (retry
++ > XS_SENDMSG_RETRY
)
405 dprintk("RPC: sendmsg returned unrecognized error %d\n",
407 xprt_disconnect(xprt
);
415 * xs_close - close a socket
418 * This is used when all requests are complete; ie, no DRC state remains
419 * on the server we want to save.
421 static void xs_close(struct rpc_xprt
*xprt
)
423 struct socket
*sock
= xprt
->sock
;
424 struct sock
*sk
= xprt
->inet
;
429 dprintk("RPC: xs_close xprt %p\n", xprt
);
431 write_lock_bh(&sk
->sk_callback_lock
);
435 sk
->sk_user_data
= NULL
;
436 sk
->sk_data_ready
= xprt
->old_data_ready
;
437 sk
->sk_state_change
= xprt
->old_state_change
;
438 sk
->sk_write_space
= xprt
->old_write_space
;
439 write_unlock_bh(&sk
->sk_callback_lock
);
447 * xs_destroy - prepare to shutdown a transport
448 * @xprt: doomed transport
451 static void xs_destroy(struct rpc_xprt
*xprt
)
453 dprintk("RPC: xs_destroy xprt %p\n", xprt
);
455 cancel_delayed_work(&xprt
->connect_worker
);
456 flush_scheduled_work();
458 xprt_disconnect(xprt
);
463 static inline struct rpc_xprt
*xprt_from_sock(struct sock
*sk
)
465 return (struct rpc_xprt
*) sk
->sk_user_data
;
469 * xs_udp_data_ready - "data ready" callback for UDP sockets
470 * @sk: socket with data to read
471 * @len: how much data to read
474 static void xs_udp_data_ready(struct sock
*sk
, int len
)
476 struct rpc_task
*task
;
477 struct rpc_xprt
*xprt
;
478 struct rpc_rqst
*rovr
;
480 int err
, repsize
, copied
;
483 read_lock(&sk
->sk_callback_lock
);
484 dprintk("RPC: xs_udp_data_ready...\n");
485 if (!(xprt
= xprt_from_sock(sk
)))
488 if ((skb
= skb_recv_datagram(sk
, 0, 1, &err
)) == NULL
)
494 repsize
= skb
->len
- sizeof(struct udphdr
);
496 dprintk("RPC: impossible RPC reply size %d!\n", repsize
);
500 /* Copy the XID from the skb... */
501 xp
= skb_header_pointer(skb
, sizeof(struct udphdr
),
502 sizeof(_xid
), &_xid
);
506 /* Look up and lock the request corresponding to the given XID */
507 spin_lock(&xprt
->transport_lock
);
508 rovr
= xprt_lookup_rqst(xprt
, *xp
);
511 task
= rovr
->rq_task
;
513 if ((copied
= rovr
->rq_private_buf
.buflen
) > repsize
)
516 /* Suck it into the iovec, verify checksum if not done by hw. */
517 if (csum_partial_copy_to_xdr(&rovr
->rq_private_buf
, skb
))
520 /* Something worked... */
521 dst_confirm(skb
->dst
);
523 xprt_adjust_cwnd(task
, copied
);
524 xprt_update_rtt(task
);
525 xprt_complete_rqst(task
, copied
);
528 spin_unlock(&xprt
->transport_lock
);
530 skb_free_datagram(sk
, skb
);
532 read_unlock(&sk
->sk_callback_lock
);
535 static inline size_t xs_tcp_copy_data(skb_reader_t
*desc
, void *p
, size_t len
)
537 if (len
> desc
->count
)
539 if (skb_copy_bits(desc
->skb
, desc
->offset
, p
, len
)) {
540 dprintk("RPC: failed to copy %zu bytes from skb. %zu bytes remain\n",
546 dprintk("RPC: copied %zu bytes from skb. %zu bytes remain\n",
551 static inline void xs_tcp_read_fraghdr(struct rpc_xprt
*xprt
, skb_reader_t
*desc
)
556 p
= ((char *) &xprt
->tcp_recm
) + xprt
->tcp_offset
;
557 len
= sizeof(xprt
->tcp_recm
) - xprt
->tcp_offset
;
558 used
= xs_tcp_copy_data(desc
, p
, len
);
559 xprt
->tcp_offset
+= used
;
563 xprt
->tcp_reclen
= ntohl(xprt
->tcp_recm
);
564 if (xprt
->tcp_reclen
& RPC_LAST_STREAM_FRAGMENT
)
565 xprt
->tcp_flags
|= XPRT_LAST_FRAG
;
567 xprt
->tcp_flags
&= ~XPRT_LAST_FRAG
;
568 xprt
->tcp_reclen
&= RPC_FRAGMENT_SIZE_MASK
;
570 xprt
->tcp_flags
&= ~XPRT_COPY_RECM
;
571 xprt
->tcp_offset
= 0;
573 /* Sanity check of the record length */
574 if (unlikely(xprt
->tcp_reclen
< 4)) {
575 dprintk("RPC: invalid TCP record fragment length\n");
576 xprt_disconnect(xprt
);
579 dprintk("RPC: reading TCP record fragment of length %d\n",
583 static void xs_tcp_check_recm(struct rpc_xprt
*xprt
)
585 dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u, tcp_flags = %lx\n",
586 xprt
, xprt
->tcp_copied
, xprt
->tcp_offset
, xprt
->tcp_reclen
, xprt
->tcp_flags
);
587 if (xprt
->tcp_offset
== xprt
->tcp_reclen
) {
588 xprt
->tcp_flags
|= XPRT_COPY_RECM
;
589 xprt
->tcp_offset
= 0;
590 if (xprt
->tcp_flags
& XPRT_LAST_FRAG
) {
591 xprt
->tcp_flags
&= ~XPRT_COPY_DATA
;
592 xprt
->tcp_flags
|= XPRT_COPY_XID
;
593 xprt
->tcp_copied
= 0;
598 static inline void xs_tcp_read_xid(struct rpc_xprt
*xprt
, skb_reader_t
*desc
)
603 len
= sizeof(xprt
->tcp_xid
) - xprt
->tcp_offset
;
604 dprintk("RPC: reading XID (%Zu bytes)\n", len
);
605 p
= ((char *) &xprt
->tcp_xid
) + xprt
->tcp_offset
;
606 used
= xs_tcp_copy_data(desc
, p
, len
);
607 xprt
->tcp_offset
+= used
;
610 xprt
->tcp_flags
&= ~XPRT_COPY_XID
;
611 xprt
->tcp_flags
|= XPRT_COPY_DATA
;
612 xprt
->tcp_copied
= 4;
613 dprintk("RPC: reading reply for XID %08x\n",
614 ntohl(xprt
->tcp_xid
));
615 xs_tcp_check_recm(xprt
);
618 static inline void xs_tcp_read_request(struct rpc_xprt
*xprt
, skb_reader_t
*desc
)
620 struct rpc_rqst
*req
;
621 struct xdr_buf
*rcvbuf
;
625 /* Find and lock the request corresponding to this xid */
626 spin_lock(&xprt
->transport_lock
);
627 req
= xprt_lookup_rqst(xprt
, xprt
->tcp_xid
);
629 xprt
->tcp_flags
&= ~XPRT_COPY_DATA
;
630 dprintk("RPC: XID %08x request not found!\n",
631 ntohl(xprt
->tcp_xid
));
632 spin_unlock(&xprt
->transport_lock
);
636 rcvbuf
= &req
->rq_private_buf
;
638 if (len
> xprt
->tcp_reclen
- xprt
->tcp_offset
) {
639 skb_reader_t my_desc
;
641 len
= xprt
->tcp_reclen
- xprt
->tcp_offset
;
642 memcpy(&my_desc
, desc
, sizeof(my_desc
));
644 r
= xdr_partial_copy_from_skb(rcvbuf
, xprt
->tcp_copied
,
645 &my_desc
, xs_tcp_copy_data
);
649 r
= xdr_partial_copy_from_skb(rcvbuf
, xprt
->tcp_copied
,
650 desc
, xs_tcp_copy_data
);
653 xprt
->tcp_copied
+= r
;
654 xprt
->tcp_offset
+= r
;
657 /* Error when copying to the receive buffer,
658 * usually because we weren't able to allocate
659 * additional buffer pages. All we can do now
660 * is turn off XPRT_COPY_DATA, so the request
661 * will not receive any additional updates,
663 * Any remaining data from this record will
666 xprt
->tcp_flags
&= ~XPRT_COPY_DATA
;
667 dprintk("RPC: XID %08x truncated request\n",
668 ntohl(xprt
->tcp_xid
));
669 dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n",
670 xprt
, xprt
->tcp_copied
, xprt
->tcp_offset
, xprt
->tcp_reclen
);
674 dprintk("RPC: XID %08x read %Zd bytes\n",
675 ntohl(xprt
->tcp_xid
), r
);
676 dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n",
677 xprt
, xprt
->tcp_copied
, xprt
->tcp_offset
, xprt
->tcp_reclen
);
679 if (xprt
->tcp_copied
== req
->rq_private_buf
.buflen
)
680 xprt
->tcp_flags
&= ~XPRT_COPY_DATA
;
681 else if (xprt
->tcp_offset
== xprt
->tcp_reclen
) {
682 if (xprt
->tcp_flags
& XPRT_LAST_FRAG
)
683 xprt
->tcp_flags
&= ~XPRT_COPY_DATA
;
687 if (!(xprt
->tcp_flags
& XPRT_COPY_DATA
))
688 xprt_complete_rqst(req
->rq_task
, xprt
->tcp_copied
);
689 spin_unlock(&xprt
->transport_lock
);
690 xs_tcp_check_recm(xprt
);
693 static inline void xs_tcp_read_discard(struct rpc_xprt
*xprt
, skb_reader_t
*desc
)
697 len
= xprt
->tcp_reclen
- xprt
->tcp_offset
;
698 if (len
> desc
->count
)
702 xprt
->tcp_offset
+= len
;
703 dprintk("RPC: discarded %Zu bytes\n", len
);
704 xs_tcp_check_recm(xprt
);
707 static int xs_tcp_data_recv(read_descriptor_t
*rd_desc
, struct sk_buff
*skb
, unsigned int offset
, size_t len
)
709 struct rpc_xprt
*xprt
= rd_desc
->arg
.data
;
710 skb_reader_t desc
= {
717 dprintk("RPC: xs_tcp_data_recv started\n");
719 /* Read in a new fragment marker if necessary */
720 /* Can we ever really expect to get completely empty fragments? */
721 if (xprt
->tcp_flags
& XPRT_COPY_RECM
) {
722 xs_tcp_read_fraghdr(xprt
, &desc
);
725 /* Read in the xid if necessary */
726 if (xprt
->tcp_flags
& XPRT_COPY_XID
) {
727 xs_tcp_read_xid(xprt
, &desc
);
730 /* Read in the request data */
731 if (xprt
->tcp_flags
& XPRT_COPY_DATA
) {
732 xs_tcp_read_request(xprt
, &desc
);
735 /* Skip over any trailing bytes on short reads */
736 xs_tcp_read_discard(xprt
, &desc
);
737 } while (desc
.count
);
738 dprintk("RPC: xs_tcp_data_recv done\n");
739 return len
- desc
.count
;
743 * xs_tcp_data_ready - "data ready" callback for TCP sockets
744 * @sk: socket with data to read
745 * @bytes: how much data to read
748 static void xs_tcp_data_ready(struct sock
*sk
, int bytes
)
750 struct rpc_xprt
*xprt
;
751 read_descriptor_t rd_desc
;
753 read_lock(&sk
->sk_callback_lock
);
754 dprintk("RPC: xs_tcp_data_ready...\n");
755 if (!(xprt
= xprt_from_sock(sk
)))
760 /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
761 rd_desc
.arg
.data
= xprt
;
762 rd_desc
.count
= 65536;
763 tcp_read_sock(sk
, &rd_desc
, xs_tcp_data_recv
);
765 read_unlock(&sk
->sk_callback_lock
);
769 * xs_tcp_state_change - callback to handle TCP socket state changes
770 * @sk: socket whose state has changed
773 static void xs_tcp_state_change(struct sock
*sk
)
775 struct rpc_xprt
*xprt
;
777 read_lock(&sk
->sk_callback_lock
);
778 if (!(xprt
= xprt_from_sock(sk
)))
780 dprintk("RPC: xs_tcp_state_change client %p...\n", xprt
);
781 dprintk("RPC: state %x conn %d dead %d zapped %d\n",
782 sk
->sk_state
, xprt_connected(xprt
),
783 sock_flag(sk
, SOCK_DEAD
),
784 sock_flag(sk
, SOCK_ZAPPED
));
786 switch (sk
->sk_state
) {
787 case TCP_ESTABLISHED
:
788 spin_lock_bh(&xprt
->transport_lock
);
789 if (!xprt_test_and_set_connected(xprt
)) {
790 /* Reset TCP record info */
791 xprt
->tcp_offset
= 0;
792 xprt
->tcp_reclen
= 0;
793 xprt
->tcp_copied
= 0;
794 xprt
->tcp_flags
= XPRT_COPY_RECM
| XPRT_COPY_XID
;
795 xprt
->reestablish_timeout
= XS_TCP_INIT_REEST_TO
;
796 xprt_wake_pending_tasks(xprt
, 0);
798 spin_unlock_bh(&xprt
->transport_lock
);
804 xprt_disconnect(xprt
);
808 read_unlock(&sk
->sk_callback_lock
);
812 * xs_udp_write_space - callback invoked when socket buffer space
814 * @sk: socket whose state has changed
816 * Called when more output buffer space is available for this socket.
817 * We try not to wake our writers until they can make "significant"
818 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
819 * with a bunch of small requests.
821 static void xs_udp_write_space(struct sock
*sk
)
823 read_lock(&sk
->sk_callback_lock
);
825 /* from net/core/sock.c:sock_def_write_space */
826 if (sock_writeable(sk
)) {
828 struct rpc_xprt
*xprt
;
830 if (unlikely(!(sock
= sk
->sk_socket
)))
832 if (unlikely(!(xprt
= xprt_from_sock(sk
))))
834 if (unlikely(!test_and_clear_bit(SOCK_NOSPACE
, &sock
->flags
)))
837 xprt_write_space(xprt
);
841 read_unlock(&sk
->sk_callback_lock
);
845 * xs_tcp_write_space - callback invoked when socket buffer space
847 * @sk: socket whose state has changed
849 * Called when more output buffer space is available for this socket.
850 * We try not to wake our writers until they can make "significant"
851 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
852 * with a bunch of small requests.
854 static void xs_tcp_write_space(struct sock
*sk
)
856 read_lock(&sk
->sk_callback_lock
);
858 /* from net/core/stream.c:sk_stream_write_space */
859 if (sk_stream_wspace(sk
) >= sk_stream_min_wspace(sk
)) {
861 struct rpc_xprt
*xprt
;
863 if (unlikely(!(sock
= sk
->sk_socket
)))
865 if (unlikely(!(xprt
= xprt_from_sock(sk
))))
867 if (unlikely(!test_and_clear_bit(SOCK_NOSPACE
, &sock
->flags
)))
870 xprt_write_space(xprt
);
874 read_unlock(&sk
->sk_callback_lock
);
877 static void xs_udp_do_set_buffer_size(struct rpc_xprt
*xprt
)
879 struct sock
*sk
= xprt
->inet
;
882 sk
->sk_userlocks
|= SOCK_RCVBUF_LOCK
;
883 sk
->sk_rcvbuf
= xprt
->rcvsize
* xprt
->max_reqs
* 2;
886 sk
->sk_userlocks
|= SOCK_SNDBUF_LOCK
;
887 sk
->sk_sndbuf
= xprt
->sndsize
* xprt
->max_reqs
* 2;
888 sk
->sk_write_space(sk
);
893 * xs_udp_set_buffer_size - set send and receive limits
894 * @xprt: generic transport
895 * @sndsize: requested size of send buffer, in bytes
896 * @rcvsize: requested size of receive buffer, in bytes
898 * Set socket send and receive buffer size limits.
900 static void xs_udp_set_buffer_size(struct rpc_xprt
*xprt
, size_t sndsize
, size_t rcvsize
)
904 xprt
->sndsize
= sndsize
+ 1024;
907 xprt
->rcvsize
= rcvsize
+ 1024;
909 xs_udp_do_set_buffer_size(xprt
);
913 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
914 * @task: task that timed out
916 * Adjust the congestion window after a retransmit timeout has occurred.
918 static void xs_udp_timer(struct rpc_task
*task
)
920 xprt_adjust_cwnd(task
, -ETIMEDOUT
);
923 static int xs_bindresvport(struct rpc_xprt
*xprt
, struct socket
*sock
)
925 struct sockaddr_in myaddr
= {
926 .sin_family
= AF_INET
,
929 unsigned short port
= xprt
->port
;
932 myaddr
.sin_port
= htons(port
);
933 err
= sock
->ops
->bind(sock
, (struct sockaddr
*) &myaddr
,
937 dprintk("RPC: xs_bindresvport bound to port %u\n",
941 if (port
<= xprt_min_resvport
)
942 port
= xprt_max_resvport
;
945 } while (err
== -EADDRINUSE
&& port
!= xprt
->port
);
947 dprintk("RPC: can't bind to reserved port (%d).\n", -err
);
952 * xs_udp_connect_worker - set up a UDP socket
953 * @args: RPC transport to connect
955 * Invoked by a work queue tasklet.
957 static void xs_udp_connect_worker(void *args
)
959 struct rpc_xprt
*xprt
= (struct rpc_xprt
*) args
;
960 struct socket
*sock
= xprt
->sock
;
961 int err
, status
= -EIO
;
963 if (xprt
->shutdown
|| xprt
->addr
.sin_port
== 0)
966 dprintk("RPC: xs_udp_connect_worker for xprt %p\n", xprt
);
968 /* Start by resetting any existing state */
971 if ((err
= sock_create_kern(PF_INET
, SOCK_DGRAM
, IPPROTO_UDP
, &sock
)) < 0) {
972 dprintk("RPC: can't create UDP transport socket (%d).\n", -err
);
976 if (xprt
->resvport
&& xs_bindresvport(xprt
, sock
) < 0) {
982 struct sock
*sk
= sock
->sk
;
984 write_lock_bh(&sk
->sk_callback_lock
);
986 sk
->sk_user_data
= xprt
;
987 xprt
->old_data_ready
= sk
->sk_data_ready
;
988 xprt
->old_state_change
= sk
->sk_state_change
;
989 xprt
->old_write_space
= sk
->sk_write_space
;
990 sk
->sk_data_ready
= xs_udp_data_ready
;
991 sk
->sk_write_space
= xs_udp_write_space
;
992 sk
->sk_no_check
= UDP_CSUM_NORCV
;
994 xprt_set_connected(xprt
);
996 /* Reset to new socket */
1000 write_unlock_bh(&sk
->sk_callback_lock
);
1002 xs_udp_do_set_buffer_size(xprt
);
1005 xprt_wake_pending_tasks(xprt
, status
);
1006 xprt_clear_connecting(xprt
);
1010 * We need to preserve the port number so the reply cache on the server can
1011 * find our cached RPC replies when we get around to reconnecting.
1013 static void xs_tcp_reuse_connection(struct rpc_xprt
*xprt
)
1016 struct socket
*sock
= xprt
->sock
;
1017 struct sockaddr any
;
1019 dprintk("RPC: disconnecting xprt %p to reuse port\n", xprt
);
1022 * Disconnect the transport socket by doing a connect operation
1023 * with AF_UNSPEC. This should return immediately...
1025 memset(&any
, 0, sizeof(any
));
1026 any
.sa_family
= AF_UNSPEC
;
1027 result
= sock
->ops
->connect(sock
, &any
, sizeof(any
), 0);
1029 dprintk("RPC: AF_UNSPEC connect return code %d\n",
1034 * xs_tcp_connect_worker - connect a TCP socket to a remote endpoint
1035 * @args: RPC transport to connect
1037 * Invoked by a work queue tasklet.
1039 static void xs_tcp_connect_worker(void *args
)
1041 struct rpc_xprt
*xprt
= (struct rpc_xprt
*)args
;
1042 struct socket
*sock
= xprt
->sock
;
1043 int err
, status
= -EIO
;
1045 if (xprt
->shutdown
|| xprt
->addr
.sin_port
== 0)
1048 dprintk("RPC: xs_tcp_connect_worker for xprt %p\n", xprt
);
1051 /* start from scratch */
1052 if ((err
= sock_create_kern(PF_INET
, SOCK_STREAM
, IPPROTO_TCP
, &sock
)) < 0) {
1053 dprintk("RPC: can't create TCP transport socket (%d).\n", -err
);
1057 if (xprt
->resvport
&& xs_bindresvport(xprt
, sock
) < 0) {
1062 /* "close" the socket, preserving the local port */
1063 xs_tcp_reuse_connection(xprt
);
1066 struct sock
*sk
= sock
->sk
;
1068 write_lock_bh(&sk
->sk_callback_lock
);
1070 sk
->sk_user_data
= xprt
;
1071 xprt
->old_data_ready
= sk
->sk_data_ready
;
1072 xprt
->old_state_change
= sk
->sk_state_change
;
1073 xprt
->old_write_space
= sk
->sk_write_space
;
1074 sk
->sk_data_ready
= xs_tcp_data_ready
;
1075 sk
->sk_state_change
= xs_tcp_state_change
;
1076 sk
->sk_write_space
= xs_tcp_write_space
;
1078 /* socket options */
1079 sk
->sk_userlocks
|= SOCK_BINDPORT_LOCK
;
1080 sock_reset_flag(sk
, SOCK_LINGER
);
1081 tcp_sk(sk
)->linger2
= 0;
1082 tcp_sk(sk
)->nonagle
|= TCP_NAGLE_OFF
;
1084 xprt_clear_connected(xprt
);
1086 /* Reset to new socket */
1090 write_unlock_bh(&sk
->sk_callback_lock
);
1093 /* Tell the socket layer to start connecting... */
1094 status
= sock
->ops
->connect(sock
, (struct sockaddr
*) &xprt
->addr
,
1095 sizeof(xprt
->addr
), O_NONBLOCK
);
1096 dprintk("RPC: %p connect status %d connected %d sock state %d\n",
1097 xprt
, -status
, xprt_connected(xprt
), sock
->sk
->sk_state
);
1105 /* retry with existing socket, after a delay */
1108 /* get rid of existing socket, and retry */
1114 xprt_wake_pending_tasks(xprt
, status
);
1116 xprt_clear_connecting(xprt
);
1120 * xs_connect - connect a socket to a remote endpoint
1121 * @task: address of RPC task that manages state of connect request
1123 * TCP: If the remote end dropped the connection, delay reconnecting.
1125 * UDP socket connects are synchronous, but we use a work queue anyway
1126 * to guarantee that even unprivileged user processes can set up a
1127 * socket on a privileged port.
1129 * If a UDP socket connect fails, the delay behavior here prevents
1130 * retry floods (hard mounts).
1132 static void xs_connect(struct rpc_task
*task
)
1134 struct rpc_xprt
*xprt
= task
->tk_xprt
;
1136 if (xprt_test_and_set_connecting(xprt
))
1139 if (xprt
->sock
!= NULL
) {
1140 dprintk("RPC: xs_connect delayed xprt %p for %lu seconds\n",
1141 xprt
, xprt
->reestablish_timeout
/ HZ
);
1142 schedule_delayed_work(&xprt
->connect_worker
,
1143 xprt
->reestablish_timeout
);
1144 xprt
->reestablish_timeout
<<= 1;
1145 if (xprt
->reestablish_timeout
> XS_TCP_MAX_REEST_TO
)
1146 xprt
->reestablish_timeout
= XS_TCP_MAX_REEST_TO
;
1148 dprintk("RPC: xs_connect scheduled xprt %p\n", xprt
);
1149 schedule_work(&xprt
->connect_worker
);
1151 /* flush_scheduled_work can sleep... */
1152 if (!RPC_IS_ASYNC(task
))
1153 flush_scheduled_work();
1157 static struct rpc_xprt_ops xs_udp_ops
= {
1158 .set_buffer_size
= xs_udp_set_buffer_size
,
1159 .reserve_xprt
= xprt_reserve_xprt_cong
,
1160 .release_xprt
= xprt_release_xprt_cong
,
1161 .connect
= xs_connect
,
1162 .send_request
= xs_udp_send_request
,
1163 .set_retrans_timeout
= xprt_set_retrans_timeout_rtt
,
1164 .timer
= xs_udp_timer
,
1165 .release_request
= xprt_release_rqst_cong
,
1167 .destroy
= xs_destroy
,
1170 static struct rpc_xprt_ops xs_tcp_ops
= {
1171 .reserve_xprt
= xprt_reserve_xprt
,
1172 .release_xprt
= xprt_release_xprt
,
1173 .connect
= xs_connect
,
1174 .send_request
= xs_tcp_send_request
,
1175 .set_retrans_timeout
= xprt_set_retrans_timeout_def
,
1177 .destroy
= xs_destroy
,
1181 * xs_setup_udp - Set up transport to use a UDP socket
1182 * @xprt: transport to set up
1183 * @to: timeout parameters
1186 int xs_setup_udp(struct rpc_xprt
*xprt
, struct rpc_timeout
*to
)
1188 size_t slot_table_size
;
1190 dprintk("RPC: setting up udp-ipv4 transport...\n");
1192 xprt
->max_reqs
= xprt_udp_slot_table_entries
;
1193 slot_table_size
= xprt
->max_reqs
* sizeof(xprt
->slot
[0]);
1194 xprt
->slot
= kmalloc(slot_table_size
, GFP_KERNEL
);
1195 if (xprt
->slot
== NULL
)
1197 memset(xprt
->slot
, 0, slot_table_size
);
1199 xprt
->prot
= IPPROTO_UDP
;
1200 xprt
->port
= xprt_max_resvport
;
1202 xprt
->resvport
= capable(CAP_NET_BIND_SERVICE
) ? 1 : 0;
1203 /* XXX: header size can vary due to auth type, IPv6, etc. */
1204 xprt
->max_payload
= (1U << 16) - (MAX_HEADER
<< 3);
1206 INIT_WORK(&xprt
->connect_worker
, xs_udp_connect_worker
, xprt
);
1207 xprt
->bind_timeout
= XS_BIND_TO
;
1208 xprt
->connect_timeout
= XS_UDP_CONN_TO
;
1209 xprt
->reestablish_timeout
= XS_UDP_REEST_TO
;
1210 xprt
->idle_timeout
= XS_IDLE_DISC_TO
;
1212 xprt
->ops
= &xs_udp_ops
;
1215 xprt
->timeout
= *to
;
1217 xprt_set_timeout(&xprt
->timeout
, 5, 5 * HZ
);
1223 * xs_setup_tcp - Set up transport to use a TCP socket
1224 * @xprt: transport to set up
1225 * @to: timeout parameters
1228 int xs_setup_tcp(struct rpc_xprt
*xprt
, struct rpc_timeout
*to
)
1230 size_t slot_table_size
;
1232 dprintk("RPC: setting up tcp-ipv4 transport...\n");
1234 xprt
->max_reqs
= xprt_tcp_slot_table_entries
;
1235 slot_table_size
= xprt
->max_reqs
* sizeof(xprt
->slot
[0]);
1236 xprt
->slot
= kmalloc(slot_table_size
, GFP_KERNEL
);
1237 if (xprt
->slot
== NULL
)
1239 memset(xprt
->slot
, 0, slot_table_size
);
1241 xprt
->prot
= IPPROTO_TCP
;
1242 xprt
->port
= xprt_max_resvport
;
1243 xprt
->tsh_size
= sizeof(rpc_fraghdr
) / sizeof(u32
);
1244 xprt
->resvport
= capable(CAP_NET_BIND_SERVICE
) ? 1 : 0;
1245 xprt
->max_payload
= RPC_MAX_FRAGMENT_SIZE
;
1247 INIT_WORK(&xprt
->connect_worker
, xs_tcp_connect_worker
, xprt
);
1248 xprt
->bind_timeout
= XS_BIND_TO
;
1249 xprt
->connect_timeout
= XS_TCP_CONN_TO
;
1250 xprt
->reestablish_timeout
= XS_TCP_INIT_REEST_TO
;
1251 xprt
->idle_timeout
= XS_IDLE_DISC_TO
;
1253 xprt
->ops
= &xs_tcp_ops
;
1256 xprt
->timeout
= *to
;
1258 xprt_set_timeout(&xprt
->timeout
, 2, 60 * HZ
);