/* * linux/net/sunrpc/xprtsock.c * * Client-side transport implementation for sockets. * * TCP callback races fixes (C) 1998 Red Hat * TCP send fixes (C) 1998 Red Hat * TCP NFS related read + write fixes * (C) 1999 Dave Airlie, University of Limerick, Ireland * * Rewrite of larges part of the code in order to stabilize TCP stuff. * Fix behaviour when socket buffer is full. * (C) 1999 Trond Myklebust * * IP socket transport implementation, (C) 2005 Chuck Lever * * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_NFS_V4_1 #include #endif #include #include #include #include #include "sunrpc.h" /* * xprtsock tunables */ unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE; unsigned int xprt_tcp_slot_table_entries = RPC_DEF_SLOT_TABLE; unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT; unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT; #define XS_TCP_LINGER_TO (15U * HZ) static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO; /* * We can register our own files under /proc/sys/sunrpc by * calling register_sysctl_table() again. The files in that * directory become the union of all files registered there. * * We simply need to make sure that we don't collide with * someone else's file names! */ #ifdef RPC_DEBUG static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE; static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE; static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT; static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT; static struct ctl_table_header *sunrpc_table_header; /* * FIXME: changing the UDP slot table size should also resize the UDP * socket buffers for existing UDP transports */ static ctl_table xs_tunables_table[] = { { .procname = "udp_slot_table_entries", .data = &xprt_udp_slot_table_entries, .maxlen = sizeof(unsigned int), .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = &min_slot_table_size, .extra2 = &max_slot_table_size }, { .procname = "tcp_slot_table_entries", .data = &xprt_tcp_slot_table_entries, .maxlen = sizeof(unsigned int), .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = &min_slot_table_size, .extra2 = &max_slot_table_size }, { .procname = "min_resvport", .data = &xprt_min_resvport, .maxlen = sizeof(unsigned int), .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = &xprt_min_resvport_limit, .extra2 = &xprt_max_resvport_limit }, { .procname = "max_resvport", .data = &xprt_max_resvport, .maxlen = sizeof(unsigned int), .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = &xprt_min_resvport_limit, .extra2 = &xprt_max_resvport_limit }, { .procname = "tcp_fin_timeout", .data = &xs_tcp_fin_timeout, .maxlen = sizeof(xs_tcp_fin_timeout), .mode = 0644, .proc_handler = proc_dointvec_jiffies, }, { }, }; static ctl_table sunrpc_table[] = { { .procname = "sunrpc", .mode = 0555, .child = xs_tunables_table }, { }, }; #endif /* * Wait duration for a reply from the RPC portmapper. */ #define XS_BIND_TO (60U * HZ) /* * Delay if a UDP socket connect error occurs. This is most likely some * kind of resource problem on the local host. */ #define XS_UDP_REEST_TO (2U * HZ) /* * The reestablish timeout allows clients to delay for a bit before attempting * to reconnect to a server that just dropped our connection. * * We implement an exponential backoff when trying to reestablish a TCP * transport connection with the server. Some servers like to drop a TCP * connection when they are overworked, so we start with a short timeout and * increase over time if the server is down or not responding. */ #define XS_TCP_INIT_REEST_TO (3U * HZ) #define XS_TCP_MAX_REEST_TO (5U * 60 * HZ) /* * TCP idle timeout; client drops the transport socket if it is idle * for this long. Note that we also timeout UDP sockets to prevent * holding port numbers when there is no RPC traffic. */ #define XS_IDLE_DISC_TO (5U * 60 * HZ) #ifdef RPC_DEBUG # undef RPC_DEBUG_DATA # define RPCDBG_FACILITY RPCDBG_TRANS #endif #ifdef RPC_DEBUG_DATA static void xs_pktdump(char *msg, u32 *packet, unsigned int count) { u8 *buf = (u8 *) packet; int j; dprintk("RPC: %s\n", msg); for (j = 0; j < count && j < 128; j += 4) { if (!(j & 31)) { if (j) dprintk("\n"); dprintk("0x%04x ", j); } dprintk("%02x%02x%02x%02x ", buf[j], buf[j+1], buf[j+2], buf[j+3]); } dprintk("\n"); } #else static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count) { /* NOP */ } #endif struct sock_xprt { struct rpc_xprt xprt; /* * Network layer */ struct socket * sock; struct sock * inet; /* * State of TCP reply receive */ __be32 tcp_fraghdr, tcp_xid, tcp_calldir; u32 tcp_offset, tcp_reclen; unsigned long tcp_copied, tcp_flags; /* * Connection of transports */ struct delayed_work connect_worker; struct sockaddr_storage srcaddr; unsigned short srcport; /* * UDP socket buffer size parameters */ size_t rcvsize, sndsize; /* * Saved socket callback addresses */ void (*old_data_ready)(struct sock *, int); void (*old_state_change)(struct sock *); void (*old_write_space)(struct sock *); void (*old_error_report)(struct sock *); }; /* * TCP receive state flags */ #define TCP_RCV_LAST_FRAG (1UL << 0) #define TCP_RCV_COPY_FRAGHDR (1UL << 1) #define TCP_RCV_COPY_XID (1UL << 2) #define TCP_RCV_COPY_DATA (1UL << 3) #define TCP_RCV_READ_CALLDIR (1UL << 4) #define TCP_RCV_COPY_CALLDIR (1UL << 5) /* * TCP RPC flags */ #define TCP_RPC_REPLY (1UL << 6) static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt) { return (struct sockaddr *) &xprt->addr; } static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt) { return (struct sockaddr_in *) &xprt->addr; } static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt) { return (struct sockaddr_in6 *) &xprt->addr; } static void xs_format_common_peer_addresses(struct rpc_xprt *xprt) { struct sockaddr *sap = xs_addr(xprt); struct sockaddr_in6 *sin6; struct sockaddr_in *sin; char buf[128]; (void)rpc_ntop(sap, buf, sizeof(buf)); xprt->address_strings[RPC_DISPLAY_ADDR] = kstrdup(buf, GFP_KERNEL); switch (sap->sa_family) { case AF_INET: sin = xs_addr_in(xprt); snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr)); break; case AF_INET6: sin6 = xs_addr_in6(xprt); snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr); break; default: BUG(); } xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL); } static void xs_format_common_peer_ports(struct rpc_xprt *xprt) { struct sockaddr *sap = xs_addr(xprt); char buf[128]; snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap)); xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL); snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap)); xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL); } static void xs_format_peer_addresses(struct rpc_xprt *xprt, const char *protocol, const char *netid) { xprt->address_strings[RPC_DISPLAY_PROTO] = protocol; xprt->address_strings[RPC_DISPLAY_NETID] = netid; xs_format_common_peer_addresses(xprt); xs_format_common_peer_ports(xprt); } static void xs_update_peer_port(struct rpc_xprt *xprt) { kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]); kfree(xprt->address_strings[RPC_DISPLAY_PORT]); xs_format_common_peer_ports(xprt); } static void xs_free_peer_addresses(struct rpc_xprt *xprt) { unsigned int i; for (i = 0; i < RPC_DISPLAY_MAX; i++) switch (i) { case RPC_DISPLAY_PROTO: case RPC_DISPLAY_NETID: continue; default: kfree(xprt->address_strings[i]); } } #define XS_SENDMSG_FLAGS (MSG_DONTWAIT | MSG_NOSIGNAL) static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more) { struct msghdr msg = { .msg_name = addr, .msg_namelen = addrlen, .msg_flags = XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0), }; struct kvec iov = { .iov_base = vec->iov_base + base, .iov_len = vec->iov_len - base, }; if (iov.iov_len != 0) return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len); return kernel_sendmsg(sock, &msg, NULL, 0, 0); } static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more) { struct page **ppage; unsigned int remainder; int err, sent = 0; remainder = xdr->page_len - base; base += xdr->page_base; ppage = xdr->pages + (base >> PAGE_SHIFT); base &= ~PAGE_MASK; for(;;) { unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder); int flags = XS_SENDMSG_FLAGS; remainder -= len; if (remainder != 0 || more) flags |= MSG_MORE; err = sock->ops->sendpage(sock, *ppage, base, len, flags); if (remainder == 0 || err != len) break; sent += err; ppage++; base = 0; } if (sent == 0) return err; if (err > 0) sent += err; return sent; } /** * xs_sendpages - write pages directly to a socket * @sock: socket to send on * @addr: UDP only -- address of destination * @addrlen: UDP only -- length of destination address * @xdr: buffer containing this request * @base: starting position in the buffer * */ static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base) { unsigned int remainder = xdr->len - base; int err, sent = 0; if (unlikely(!sock)) return -ENOTSOCK; clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags); if (base != 0) { addr = NULL; addrlen = 0; } if (base < xdr->head[0].iov_len || addr != NULL) { unsigned int len = xdr->head[0].iov_len - base; remainder -= len; err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0); if (remainder == 0 || err != len) goto out; sent += err; base = 0; } else base -= xdr->head[0].iov_len; if (base < xdr->page_len) { unsigned int len = xdr->page_len - base; remainder -= len; err = xs_send_pagedata(sock, xdr, base, remainder != 0); if (remainder == 0 || err != len) goto out; sent += err; base = 0; } else base -= xdr->page_len; if (base >= xdr->tail[0].iov_len) return sent; err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0); out: if (sent == 0) return err; if (err > 0) sent += err; return sent; } static void xs_nospace_callback(struct rpc_task *task) { struct sock_xprt *transport = container_of(task->tk_rqstp->rq_xprt, struct sock_xprt, xprt); transport->inet->sk_write_pending--; clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags); } /** * xs_nospace - place task on wait queue if transmit was incomplete * @task: task to put to sleep * */ static int xs_nospace(struct rpc_task *task) { struct rpc_rqst *req = task->tk_rqstp; struct rpc_xprt *xprt = req->rq_xprt; struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); int ret = 0; dprintk("RPC: %5u xmit incomplete (%u left of %u)\n", task->tk_pid, req->rq_slen - req->rq_bytes_sent, req->rq_slen); /* Protect against races with write_space */ spin_lock_bh(&xprt->transport_lock); /* Don't race with disconnect */ if (xprt_connected(xprt)) { if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) { ret = -EAGAIN; /* * Notify TCP that we're limited by the application * window size */ set_bit(SOCK_NOSPACE, &transport->sock->flags); transport->inet->sk_write_pending++; /* ...and wait for more buffer space */ xprt_wait_for_buffer_space(task, xs_nospace_callback); } } else { clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags); ret = -ENOTCONN; } spin_unlock_bh(&xprt->transport_lock); return ret; } /** * xs_udp_send_request - write an RPC request to a UDP socket * @task: address of RPC task that manages the state of an RPC request * * Return values: * 0: The request has been sent * EAGAIN: The socket was blocked, please call again later to * complete the request * ENOTCONN: Caller needs to invoke connect logic then call again * other: Some other error occured, the request was not sent */ static int xs_udp_send_request(struct rpc_task *task) { struct rpc_rqst *req = task->tk_rqstp; struct rpc_xprt *xprt = req->rq_xprt; struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); struct xdr_buf *xdr = &req->rq_snd_buf; int status; xs_pktdump("packet data:", req->rq_svec->iov_base, req->rq_svec->iov_len); if (!xprt_bound(xprt)) return -ENOTCONN; status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen, xdr, req->rq_bytes_sent); dprintk("RPC: xs_udp_send_request(%u) = %d\n", xdr->len - req->rq_bytes_sent, status); if (status >= 0) { req->rq_xmit_bytes_sent += status; if (status >= req->rq_slen) return 0; /* Still some bytes left; set up for a retry later. */ status = -EAGAIN; } switch (status) { case -ENOTSOCK: status = -ENOTCONN; /* Should we call xs_close() here? */ break; case -EAGAIN: status = xs_nospace(task); break; default: dprintk("RPC: sendmsg returned unrecognized error %d\n", -status); case -ENETUNREACH: case -EPIPE: case -ECONNREFUSED: /* When the server has died, an ICMP port unreachable message * prompts ECONNREFUSED. */ clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags); } return status; } /** * xs_tcp_shutdown - gracefully shut down a TCP socket * @xprt: transport * * Initiates a graceful shutdown of the TCP socket by calling the * equivalent of shutdown(SHUT_WR); */ static void xs_tcp_shutdown(struct rpc_xprt *xprt) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); struct socket *sock = transport->sock; if (sock != NULL) kernel_sock_shutdown(sock, SHUT_WR); } static inline void xs_encode_tcp_record_marker(struct xdr_buf *buf) { u32 reclen = buf->len - sizeof(rpc_fraghdr); rpc_fraghdr *base = buf->head[0].iov_base; *base = htonl(RPC_LAST_STREAM_FRAGMENT | reclen); } /** * xs_tcp_send_request - write an RPC request to a TCP socket * @task: address of RPC task that manages the state of an RPC request * * Return values: * 0: The request has been sent * EAGAIN: The socket was blocked, please call again later to * complete the request * ENOTCONN: Caller needs to invoke connect logic then call again * other: Some other error occured, the request was not sent * * XXX: In the case of soft timeouts, should we eventually give up * if sendmsg is not able to make progress? */ static int xs_tcp_send_request(struct rpc_task *task) { struct rpc_rqst *req = task->tk_rqstp; struct rpc_xprt *xprt = req->rq_xprt; struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); struct xdr_buf *xdr = &req->rq_snd_buf; int status; xs_encode_tcp_record_marker(&req->rq_snd_buf); xs_pktdump("packet data:", req->rq_svec->iov_base, req->rq_svec->iov_len); /* Continue transmitting the packet/record. We must be careful * to cope with writespace callbacks arriving _after_ we have * called sendmsg(). */ while (1) { status = xs_sendpages(transport->sock, NULL, 0, xdr, req->rq_bytes_sent); dprintk("RPC: xs_tcp_send_request(%u) = %d\n", xdr->len - req->rq_bytes_sent, status); if (unlikely(status < 0)) break; /* If we've sent the entire packet, immediately * reset the count of bytes sent. */ req->rq_bytes_sent += status; req->rq_xmit_bytes_sent += status; if (likely(req->rq_bytes_sent >= req->rq_slen)) { req->rq_bytes_sent = 0; return 0; } if (status != 0) continue; status = -EAGAIN; break; } switch (status) { case -ENOTSOCK: status = -ENOTCONN; /* Should we call xs_close() here? */ break; case -EAGAIN: status = xs_nospace(task); break; default: dprintk("RPC: sendmsg returned unrecognized error %d\n", -status); case -ECONNRESET: case -EPIPE: xs_tcp_shutdown(xprt); case -ECONNREFUSED: case -ENOTCONN: clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags); } return status; } /** * xs_tcp_release_xprt - clean up after a tcp transmission * @xprt: transport * @task: rpc task * * This cleans up if an error causes us to abort the transmission of a request. * In this case, the socket may need to be reset in order to avoid confusing * the server. */ static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) { struct rpc_rqst *req; if (task != xprt->snd_task) return; if (task == NULL) goto out_release; req = task->tk_rqstp; if (req->rq_bytes_sent == 0) goto out_release; if (req->rq_bytes_sent == req->rq_snd_buf.len) goto out_release; set_bit(XPRT_CLOSE_WAIT, &task->tk_xprt->state); out_release: xprt_release_xprt(xprt, task); } static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk) { transport->old_data_ready = sk->sk_data_ready; transport->old_state_change = sk->sk_state_change; transport->old_write_space = sk->sk_write_space; transport->old_error_report = sk->sk_error_report; } static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk) { sk->sk_data_ready = transport->old_data_ready; sk->sk_state_change = transport->old_state_change; sk->sk_write_space = transport->old_write_space; sk->sk_error_report = transport->old_error_report; } static void xs_reset_transport(struct sock_xprt *transport) { struct socket *sock = transport->sock; struct sock *sk = transport->inet; if (sk == NULL) return; write_lock_bh(&sk->sk_callback_lock); transport->inet = NULL; transport->sock = NULL; sk->sk_user_data = NULL; xs_restore_old_callbacks(transport, sk); write_unlock_bh(&sk->sk_callback_lock); sk->sk_no_check = 0; sock_release(sock); } /** * xs_close - close a socket * @xprt: transport * * This is used when all requests are complete; ie, no DRC state remains * on the server we want to save. * * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with * xs_reset_transport() zeroing the socket from underneath a writer. */ static void xs_close(struct rpc_xprt *xprt) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); dprintk("RPC: xs_close xprt %p\n", xprt); xs_reset_transport(transport); xprt->reestablish_timeout = 0; smp_mb__before_clear_bit(); clear_bit(XPRT_CONNECTION_ABORT, &xprt->state); clear_bit(XPRT_CLOSE_WAIT, &xprt->state); clear_bit(XPRT_CLOSING, &xprt->state); smp_mb__after_clear_bit(); xprt_disconnect_done(xprt); } static void xs_tcp_close(struct rpc_xprt *xprt) { if (test_and_clear_bit(XPRT_CONNECTION_CLOSE, &xprt->state)) xs_close(xprt); else xs_tcp_shutdown(xprt); } /** * xs_destroy - prepare to shutdown a transport * @xprt: doomed transport * */ static void xs_destroy(struct rpc_xprt *xprt) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); dprintk("RPC: xs_destroy xprt %p\n", xprt); cancel_rearming_delayed_work(&transport->connect_worker); xs_close(xprt); xs_free_peer_addresses(xprt); xprt_free(xprt); module_put(THIS_MODULE); } static inline struct rpc_xprt *xprt_from_sock(struct sock *sk) { return (struct rpc_xprt *) sk->sk_user_data; } /** * xs_udp_data_ready - "data ready" callback for UDP sockets * @sk: socket with data to read * @len: how much data to read * */ static void xs_udp_data_ready(struct sock *sk, int len) { struct rpc_task *task; struct rpc_xprt *xprt; struct rpc_rqst *rovr; struct sk_buff *skb; int err, repsize, copied; u32 _xid; __be32 *xp; read_lock_bh(&sk->sk_callback_lock); dprintk("RPC: xs_udp_data_ready...\n"); if (!(xprt = xprt_from_sock(sk))) goto out; if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL) goto out; if (xprt->shutdown) goto dropit; repsize = skb->len - sizeof(struct udphdr); if (repsize < 4) { dprintk("RPC: impossible RPC reply size %d!\n", repsize); goto dropit; } /* Copy the XID from the skb... */ xp = skb_header_pointer(skb, sizeof(struct udphdr), sizeof(_xid), &_xid); if (xp == NULL) goto dropit; /* Look up and lock the request corresponding to the given XID */ spin_lock(&xprt->transport_lock); rovr = xprt_lookup_rqst(xprt, *xp); if (!rovr) goto out_unlock; task = rovr->rq_task; if ((copied = rovr->rq_private_buf.buflen) > repsize) copied = repsize; /* Suck it into the iovec, verify checksum if not done by hw. */ if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) { UDPX_INC_STATS_BH(sk, UDP_MIB_INERRORS); goto out_unlock; } UDPX_INC_STATS_BH(sk, UDP_MIB_INDATAGRAMS); /* Something worked... */ dst_confirm(skb_dst(skb)); xprt_adjust_cwnd(task, copied); xprt_complete_rqst(task, copied); out_unlock: spin_unlock(&xprt->transport_lock); dropit: skb_free_datagram(sk, skb); out: read_unlock_bh(&sk->sk_callback_lock); } static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); size_t len, used; char *p; p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset; len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset; used = xdr_skb_read_bits(desc, p, len); transport->tcp_offset += used; if (used != len) return; transport->tcp_reclen = ntohl(transport->tcp_fraghdr); if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT) transport->tcp_flags |= TCP_RCV_LAST_FRAG; else transport->tcp_flags &= ~TCP_RCV_LAST_FRAG; transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK; transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR; transport->tcp_offset = 0; /* Sanity check of the record length */ if (unlikely(transport->tcp_reclen < 8)) { dprintk("RPC: invalid TCP record fragment length\n"); xprt_force_disconnect(xprt); return; } dprintk("RPC: reading TCP record fragment of length %d\n", transport->tcp_reclen); } static void xs_tcp_check_fraghdr(struct sock_xprt *transport) { if (transport->tcp_offset == transport->tcp_reclen) { transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR; transport->tcp_offset = 0; if (transport->tcp_flags & TCP_RCV_LAST_FRAG) { transport->tcp_flags &= ~TCP_RCV_COPY_DATA; transport->tcp_flags |= TCP_RCV_COPY_XID; transport->tcp_copied = 0; } } } static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc) { size_t len, used; char *p; len = sizeof(transport->tcp_xid) - transport->tcp_offset; dprintk("RPC: reading XID (%Zu bytes)\n", len); p = ((char *) &transport->tcp_xid) + transport->tcp_offset; used = xdr_skb_read_bits(desc, p, len); transport->tcp_offset += used; if (used != len) return; transport->tcp_flags &= ~TCP_RCV_COPY_XID; transport->tcp_flags |= TCP_RCV_READ_CALLDIR; transport->tcp_copied = 4; dprintk("RPC: reading %s XID %08x\n", (transport->tcp_flags & TCP_RPC_REPLY) ? "reply for" : "request with", ntohl(transport->tcp_xid)); xs_tcp_check_fraghdr(transport); } static inline void xs_tcp_read_calldir(struct sock_xprt *transport, struct xdr_skb_reader *desc) { size_t len, used; u32 offset; char *p; /* * We want transport->tcp_offset to be 8 at the end of this routine * (4 bytes for the xid and 4 bytes for the call/reply flag). * When this function is called for the first time, * transport->tcp_offset is 4 (after having already read the xid). */ offset = transport->tcp_offset - sizeof(transport->tcp_xid); len = sizeof(transport->tcp_calldir) - offset; dprintk("RPC: reading CALL/REPLY flag (%Zu bytes)\n", len); p = ((char *) &transport->tcp_calldir) + offset; used = xdr_skb_read_bits(desc, p, len); transport->tcp_offset += used; if (used != len) return; transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR; /* * We don't yet have the XDR buffer, so we will write the calldir * out after we get the buffer from the 'struct rpc_rqst' */ switch (ntohl(transport->tcp_calldir)) { case RPC_REPLY: transport->tcp_flags |= TCP_RCV_COPY_CALLDIR; transport->tcp_flags |= TCP_RCV_COPY_DATA; transport->tcp_flags |= TCP_RPC_REPLY; break; case RPC_CALL: transport->tcp_flags |= TCP_RCV_COPY_CALLDIR; transport->tcp_flags |= TCP_RCV_COPY_DATA; transport->tcp_flags &= ~TCP_RPC_REPLY; break; default: dprintk("RPC: invalid request message type\n"); xprt_force_disconnect(&transport->xprt); } xs_tcp_check_fraghdr(transport); } static inline void xs_tcp_read_common(struct rpc_xprt *xprt, struct xdr_skb_reader *desc, struct rpc_rqst *req) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); struct xdr_buf *rcvbuf; size_t len; ssize_t r; rcvbuf = &req->rq_private_buf; if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) { /* * Save the RPC direction in the XDR buffer */ memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied, &transport->tcp_calldir, sizeof(transport->tcp_calldir)); transport->tcp_copied += sizeof(transport->tcp_calldir); transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR; } len = desc->count; if (len > transport->tcp_reclen - transport->tcp_offset) { struct xdr_skb_reader my_desc; len = transport->tcp_reclen - transport->tcp_offset; memcpy(&my_desc, desc, sizeof(my_desc)); my_desc.count = len; r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied, &my_desc, xdr_skb_read_bits); desc->count -= r; desc->offset += r; } else r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied, desc, xdr_skb_read_bits); if (r > 0) { transport->tcp_copied += r; transport->tcp_offset += r; } if (r != len) { /* Error when copying to the receive buffer, * usually because we weren't able to allocate * additional buffer pages. All we can do now * is turn off TCP_RCV_COPY_DATA, so the request * will not receive any additional updates, * and time out. * Any remaining data from this record will * be discarded. */ transport->tcp_flags &= ~TCP_RCV_COPY_DATA; dprintk("RPC: XID %08x truncated request\n", ntohl(transport->tcp_xid)); dprintk("RPC: xprt = %p, tcp_copied = %lu, " "tcp_offset = %u, tcp_reclen = %u\n", xprt, transport->tcp_copied, transport->tcp_offset, transport->tcp_reclen); return; } dprintk("RPC: XID %08x read %Zd bytes\n", ntohl(transport->tcp_xid), r); dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, " "tcp_reclen = %u\n", xprt, transport->tcp_copied, transport->tcp_offset, transport->tcp_reclen); if (transport->tcp_copied == req->rq_private_buf.buflen) transport->tcp_flags &= ~TCP_RCV_COPY_DATA; else if (transport->tcp_offset == transport->tcp_reclen) { if (transport->tcp_flags & TCP_RCV_LAST_FRAG) transport->tcp_flags &= ~TCP_RCV_COPY_DATA; } } /* * Finds the request corresponding to the RPC xid and invokes the common * tcp read code to read the data. */ static inline int xs_tcp_read_reply(struct rpc_xprt *xprt, struct xdr_skb_reader *desc) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); struct rpc_rqst *req; dprintk("RPC: read reply XID %08x\n", ntohl(transport->tcp_xid)); /* Find and lock the request corresponding to this xid */ spin_lock(&xprt->transport_lock); req = xprt_lookup_rqst(xprt, transport->tcp_xid); if (!req) { dprintk("RPC: XID %08x request not found!\n", ntohl(transport->tcp_xid)); spin_unlock(&xprt->transport_lock); return -1; } xs_tcp_read_common(xprt, desc, req); if (!(transport->tcp_flags & TCP_RCV_COPY_DATA)) xprt_complete_rqst(req->rq_task, transport->tcp_copied); spin_unlock(&xprt->transport_lock); return 0; } #if defined(CONFIG_NFS_V4_1) /* * Obtains an rpc_rqst previously allocated and invokes the common * tcp read code to read the data. The result is placed in the callback * queue. * If we're unable to obtain the rpc_rqst we schedule the closing of the * connection and return -1. */ static inline int xs_tcp_read_callback(struct rpc_xprt *xprt, struct xdr_skb_reader *desc) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); struct rpc_rqst *req; req = xprt_alloc_bc_request(xprt); if (req == NULL) { printk(KERN_WARNING "Callback slot table overflowed\n"); xprt_force_disconnect(xprt); return -1; } req->rq_xid = transport->tcp_xid; dprintk("RPC: read callback XID %08x\n", ntohl(req->rq_xid)); xs_tcp_read_common(xprt, desc, req); if (!(transport->tcp_flags & TCP_RCV_COPY_DATA)) { struct svc_serv *bc_serv = xprt->bc_serv; /* * Add callback request to callback list. The callback * service sleeps on the sv_cb_waitq waiting for new * requests. Wake it up after adding enqueing the * request. */ dprintk("RPC: add callback request to list\n"); spin_lock(&bc_serv->sv_cb_lock); list_add(&req->rq_bc_list, &bc_serv->sv_cb_list); spin_unlock(&bc_serv->sv_cb_lock); wake_up(&bc_serv->sv_cb_waitq); } req->rq_private_buf.len = transport->tcp_copied; return 0; } static inline int _xs_tcp_read_data(struct rpc_xprt *xprt, struct xdr_skb_reader *desc) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); return (transport->tcp_flags & TCP_RPC_REPLY) ? xs_tcp_read_reply(xprt, desc) : xs_tcp_read_callback(xprt, desc); } #else static inline int _xs_tcp_read_data(struct rpc_xprt *xprt, struct xdr_skb_reader *desc) { return xs_tcp_read_reply(xprt, desc); } #endif /* CONFIG_NFS_V4_1 */ /* * Read data off the transport. This can be either an RPC_CALL or an * RPC_REPLY. Relay the processing to helper functions. */ static void xs_tcp_read_data(struct rpc_xprt *xprt, struct xdr_skb_reader *desc) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); if (_xs_tcp_read_data(xprt, desc) == 0) xs_tcp_check_fraghdr(transport); else { /* * The transport_lock protects the request handling. * There's no need to hold it to update the tcp_flags. */ transport->tcp_flags &= ~TCP_RCV_COPY_DATA; } } static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc) { size_t len; len = transport->tcp_reclen - transport->tcp_offset; if (len > desc->count) len = desc->count; desc->count -= len; desc->offset += len; transport->tcp_offset += len; dprintk("RPC: discarded %Zu bytes\n", len); xs_tcp_check_fraghdr(transport); } static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len) { struct rpc_xprt *xprt = rd_desc->arg.data; struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); struct xdr_skb_reader desc = { .skb = skb, .offset = offset, .count = len, }; dprintk("RPC: xs_tcp_data_recv started\n"); do { /* Read in a new fragment marker if necessary */ /* Can we ever really expect to get completely empty fragments? */ if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) { xs_tcp_read_fraghdr(xprt, &desc); continue; } /* Read in the xid if necessary */ if (transport->tcp_flags & TCP_RCV_COPY_XID) { xs_tcp_read_xid(transport, &desc); continue; } /* Read in the call/reply flag */ if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) { xs_tcp_read_calldir(transport, &desc); continue; } /* Read in the request data */ if (transport->tcp_flags & TCP_RCV_COPY_DATA) { xs_tcp_read_data(xprt, &desc); continue; } /* Skip over any trailing bytes on short reads */ xs_tcp_read_discard(transport, &desc); } while (desc.count); dprintk("RPC: xs_tcp_data_recv done\n"); return len - desc.count; } /** * xs_tcp_data_ready - "data ready" callback for TCP sockets * @sk: socket with data to read * @bytes: how much data to read * */ static void xs_tcp_data_ready(struct sock *sk, int bytes) { struct rpc_xprt *xprt; read_descriptor_t rd_desc; int read; dprintk("RPC: xs_tcp_data_ready...\n"); read_lock_bh(&sk->sk_callback_lock); if (!(xprt = xprt_from_sock(sk))) goto out; if (xprt->shutdown) goto out; /* Any data means we had a useful conversation, so * the we don't need to delay the next reconnect */ if (xprt->reestablish_timeout) xprt->reestablish_timeout = 0; /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */ rd_desc.arg.data = xprt; do { rd_desc.count = 65536; read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv); } while (read > 0); out: read_unlock_bh(&sk->sk_callback_lock); } /* * Do the equivalent of linger/linger2 handling for dealing with * broken servers that don't close the socket in a timely * fashion */ static void xs_tcp_schedule_linger_timeout(struct rpc_xprt *xprt, unsigned long timeout) { struct sock_xprt *transport; if (xprt_test_and_set_connecting(xprt)) return; set_bit(XPRT_CONNECTION_ABORT, &xprt->state); transport = container_of(xprt, struct sock_xprt, xprt); queue_delayed_work(rpciod_workqueue, &transport->connect_worker, timeout); } static void xs_tcp_cancel_linger_timeout(struct rpc_xprt *xprt) { struct sock_xprt *transport; transport = container_of(xprt, struct sock_xprt, xprt); if (!test_bit(XPRT_CONNECTION_ABORT, &xprt->state) || !cancel_delayed_work(&transport->connect_worker)) return; clear_bit(XPRT_CONNECTION_ABORT, &xprt->state); xprt_clear_connecting(xprt); } static void xs_sock_mark_closed(struct rpc_xprt *xprt) { smp_mb__before_clear_bit(); clear_bit(XPRT_CLOSE_WAIT, &xprt->state); clear_bit(XPRT_CLOSING, &xprt->state); smp_mb__after_clear_bit(); /* Mark transport as closed and wake up all pending tasks */ xprt_disconnect_done(xprt); } /** * xs_tcp_state_change - callback to handle TCP socket state changes * @sk: socket whose state has changed * */ static void xs_tcp_state_change(struct sock *sk) { struct rpc_xprt *xprt; read_lock_bh(&sk->sk_callback_lock); if (!(xprt = xprt_from_sock(sk))) goto out; dprintk("RPC: xs_tcp_state_change client %p...\n", xprt); dprintk("RPC: state %x conn %d dead %d zapped %d sk_shutdown %d\n", sk->sk_state, xprt_connected(xprt), sock_flag(sk, SOCK_DEAD), sock_flag(sk, SOCK_ZAPPED), sk->sk_shutdown); switch (sk->sk_state) { case TCP_ESTABLISHED: spin_lock(&xprt->transport_lock); if (!xprt_test_and_set_connected(xprt)) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); /* Reset TCP record info */ transport->tcp_offset = 0; transport->tcp_reclen = 0; transport->tcp_copied = 0; transport->tcp_flags = TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID; xprt_wake_pending_tasks(xprt, -EAGAIN); } spin_unlock(&xprt->transport_lock); break; case TCP_FIN_WAIT1: /* The client initiated a shutdown of the socket */ xprt->connect_cookie++; xprt->reestablish_timeout = 0; set_bit(XPRT_CLOSING, &xprt->state); smp_mb__before_clear_bit(); clear_bit(XPRT_CONNECTED, &xprt->state); clear_bit(XPRT_CLOSE_WAIT, &xprt->state); smp_mb__after_clear_bit(); xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout); break; case TCP_CLOSE_WAIT: /* The server initiated a shutdown of the socket */ xprt_force_disconnect(xprt); case TCP_SYN_SENT: xprt->connect_cookie++; case TCP_CLOSING: /* * If the server closed down the connection, make sure that * we back off before reconnecting */ if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO) xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; break; case TCP_LAST_ACK: set_bit(XPRT_CLOSING, &xprt->state); xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout); smp_mb__before_clear_bit(); clear_bit(XPRT_CONNECTED, &xprt->state); smp_mb__after_clear_bit(); break; case TCP_CLOSE: xs_tcp_cancel_linger_timeout(xprt); xs_sock_mark_closed(xprt); } out: read_unlock_bh(&sk->sk_callback_lock); } /** * xs_error_report - callback mainly for catching socket errors * @sk: socket */ static void xs_error_report(struct sock *sk) { struct rpc_xprt *xprt; read_lock_bh(&sk->sk_callback_lock); if (!(xprt = xprt_from_sock(sk))) goto out; dprintk("RPC: %s client %p...\n" "RPC: error %d\n", __func__, xprt, sk->sk_err); xprt_wake_pending_tasks(xprt, -EAGAIN); out: read_unlock_bh(&sk->sk_callback_lock); } static void xs_write_space(struct sock *sk) { struct socket *sock; struct rpc_xprt *xprt; if (unlikely(!(sock = sk->sk_socket))) return; clear_bit(SOCK_NOSPACE, &sock->flags); if (unlikely(!(xprt = xprt_from_sock(sk)))) return; if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0) return; xprt_write_space(xprt); } /** * xs_udp_write_space - callback invoked when socket buffer space * becomes available * @sk: socket whose state has changed * * Called when more output buffer space is available for this socket. * We try not to wake our writers until they can make "significant" * progress, otherwise we'll waste resources thrashing kernel_sendmsg * with a bunch of small requests. */ static void xs_udp_write_space(struct sock *sk) { read_lock_bh(&sk->sk_callback_lock); /* from net/core/sock.c:sock_def_write_space */ if (sock_writeable(sk)) xs_write_space(sk); read_unlock_bh(&sk->sk_callback_lock); } /** * xs_tcp_write_space - callback invoked when socket buffer space * becomes available * @sk: socket whose state has changed * * Called when more output buffer space is available for this socket. * We try not to wake our writers until they can make "significant" * progress, otherwise we'll waste resources thrashing kernel_sendmsg * with a bunch of small requests. */ static void xs_tcp_write_space(struct sock *sk) { read_lock_bh(&sk->sk_callback_lock); /* from net/core/stream.c:sk_stream_write_space */ if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) xs_write_space(sk); read_unlock_bh(&sk->sk_callback_lock); } static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); struct sock *sk = transport->inet; if (transport->rcvsize) { sk->sk_userlocks |= SOCK_RCVBUF_LOCK; sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2; } if (transport->sndsize) { sk->sk_userlocks |= SOCK_SNDBUF_LOCK; sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2; sk->sk_write_space(sk); } } /** * xs_udp_set_buffer_size - set send and receive limits * @xprt: generic transport * @sndsize: requested size of send buffer, in bytes * @rcvsize: requested size of receive buffer, in bytes * * Set socket send and receive buffer size limits. */ static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); transport->sndsize = 0; if (sndsize) transport->sndsize = sndsize + 1024; transport->rcvsize = 0; if (rcvsize) transport->rcvsize = rcvsize + 1024; xs_udp_do_set_buffer_size(xprt); } /** * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport * @task: task that timed out * * Adjust the congestion window after a retransmit timeout has occurred. */ static void xs_udp_timer(struct rpc_task *task) { xprt_adjust_cwnd(task, -ETIMEDOUT); } static unsigned short xs_get_random_port(void) { unsigned short range = xprt_max_resvport - xprt_min_resvport; unsigned short rand = (unsigned short) net_random() % range; return rand + xprt_min_resvport; } /** * xs_set_port - reset the port number in the remote endpoint address * @xprt: generic transport * @port: new port number * */ static void xs_set_port(struct rpc_xprt *xprt, unsigned short port) { dprintk("RPC: setting port for xprt %p to %u\n", xprt, port); rpc_set_port(xs_addr(xprt), port); xs_update_peer_port(xprt); } static unsigned short xs_get_srcport(struct sock_xprt *transport) { unsigned short port = transport->srcport; if (port == 0 && transport->xprt.resvport) port = xs_get_random_port(); return port; } static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port) { if (transport->srcport != 0) transport->srcport = 0; if (!transport->xprt.resvport) return 0; if (port <= xprt_min_resvport || port > xprt_max_resvport) return xprt_max_resvport; return --port; } static int xs_bind(struct sock_xprt *transport, struct socket *sock) { struct sockaddr_storage myaddr; int err, nloop = 0; unsigned short port = xs_get_srcport(transport); unsigned short last; memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen); do { rpc_set_port((struct sockaddr *)&myaddr, port); err = kernel_bind(sock, (struct sockaddr *)&myaddr, transport->xprt.addrlen); if (port == 0) break; if (err == 0) { transport->srcport = port; break; } last = port; port = xs_next_srcport(transport, port); if (port > last) nloop++; } while (err == -EADDRINUSE && nloop != 2); if (myaddr.ss_family == AF_INET) dprintk("RPC: %s %pI4:%u: %s (%d)\n", __func__, &((struct sockaddr_in *)&myaddr)->sin_addr, port, err ? "failed" : "ok", err); else dprintk("RPC: %s %pI6:%u: %s (%d)\n", __func__, &((struct sockaddr_in6 *)&myaddr)->sin6_addr, port, err ? "failed" : "ok", err); return err; } #ifdef CONFIG_DEBUG_LOCK_ALLOC static struct lock_class_key xs_key[2]; static struct lock_class_key xs_slock_key[2]; static inline void xs_reclassify_socket4(struct socket *sock) { struct sock *sk = sock->sk; BUG_ON(sock_owned_by_user(sk)); sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC", &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]); } static inline void xs_reclassify_socket6(struct socket *sock) { struct sock *sk = sock->sk; BUG_ON(sock_owned_by_user(sk)); sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC", &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]); } static inline void xs_reclassify_socket(int family, struct socket *sock) { switch (family) { case AF_INET: xs_reclassify_socket4(sock); break; case AF_INET6: xs_reclassify_socket6(sock); break; } } #else static inline void xs_reclassify_socket4(struct socket *sock) { } static inline void xs_reclassify_socket6(struct socket *sock) { } static inline void xs_reclassify_socket(int family, struct socket *sock) { } #endif static struct socket *xs_create_sock(struct rpc_xprt *xprt, struct sock_xprt *transport, int family, int type, int protocol) { struct socket *sock; int err; err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1); if (err < 0) { dprintk("RPC: can't create %d transport socket (%d).\n", protocol, -err); goto out; } xs_reclassify_socket(family, sock); if (xs_bind(transport, sock)) { sock_release(sock); goto out; } return sock; out: return ERR_PTR(err); } static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); if (!transport->inet) { struct sock *sk = sock->sk; write_lock_bh(&sk->sk_callback_lock); xs_save_old_callbacks(transport, sk); sk->sk_user_data = xprt; sk->sk_data_ready = xs_udp_data_ready; sk->sk_write_space = xs_udp_write_space; sk->sk_error_report = xs_error_report; sk->sk_no_check = UDP_CSUM_NORCV; sk->sk_allocation = GFP_ATOMIC; xprt_set_connected(xprt); /* Reset to new socket */ transport->sock = sock; transport->inet = sk; write_unlock_bh(&sk->sk_callback_lock); } xs_udp_do_set_buffer_size(xprt); } static void xs_udp_setup_socket(struct work_struct *work) { struct sock_xprt *transport = container_of(work, struct sock_xprt, connect_worker.work); struct rpc_xprt *xprt = &transport->xprt; struct socket *sock = transport->sock; int status = -EIO; if (xprt->shutdown) goto out; /* Start by resetting any existing state */ xs_reset_transport(transport); sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family, SOCK_DGRAM, IPPROTO_UDP); if (IS_ERR(sock)) goto out; dprintk("RPC: worker connecting xprt %p via %s to " "%s (port %s)\n", xprt, xprt->address_strings[RPC_DISPLAY_PROTO], xprt->address_strings[RPC_DISPLAY_ADDR], xprt->address_strings[RPC_DISPLAY_PORT]); xs_udp_finish_connecting(xprt, sock); status = 0; out: xprt_clear_connecting(xprt); xprt_wake_pending_tasks(xprt, status); } /* * We need to preserve the port number so the reply cache on the server can * find our cached RPC replies when we get around to reconnecting. */ static void xs_abort_connection(struct sock_xprt *transport) { int result; struct sockaddr any; dprintk("RPC: disconnecting xprt %p to reuse port\n", transport); /* * Disconnect the transport socket by doing a connect operation * with AF_UNSPEC. This should return immediately... */ memset(&any, 0, sizeof(any)); any.sa_family = AF_UNSPEC; result = kernel_connect(transport->sock, &any, sizeof(any), 0); if (!result) xs_sock_mark_closed(&transport->xprt); else dprintk("RPC: AF_UNSPEC connect return code %d\n", result); } static void xs_tcp_reuse_connection(struct sock_xprt *transport) { unsigned int state = transport->inet->sk_state; if (state == TCP_CLOSE && transport->sock->state == SS_UNCONNECTED) { /* we don't need to abort the connection if the socket * hasn't undergone a shutdown */ if (transport->inet->sk_shutdown == 0) return; dprintk("RPC: %s: TCP_CLOSEd and sk_shutdown set to %d\n", __func__, transport->inet->sk_shutdown); } if ((1 << state) & (TCPF_ESTABLISHED|TCPF_SYN_SENT)) { /* we don't need to abort the connection if the socket * hasn't undergone a shutdown */ if (transport->inet->sk_shutdown == 0) return; dprintk("RPC: %s: ESTABLISHED/SYN_SENT " "sk_shutdown set to %d\n", __func__, transport->inet->sk_shutdown); } xs_abort_connection(transport); } static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); if (!transport->inet) { struct sock *sk = sock->sk; write_lock_bh(&sk->sk_callback_lock); xs_save_old_callbacks(transport, sk); sk->sk_user_data = xprt; sk->sk_data_ready = xs_tcp_data_ready; sk->sk_state_change = xs_tcp_state_change; sk->sk_write_space = xs_tcp_write_space; sk->sk_error_report = xs_error_report; sk->sk_allocation = GFP_ATOMIC; /* socket options */ sk->sk_userlocks |= SOCK_BINDPORT_LOCK; sock_reset_flag(sk, SOCK_LINGER); tcp_sk(sk)->linger2 = 0; tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF; xprt_clear_connected(xprt); /* Reset to new socket */ transport->sock = sock; transport->inet = sk; write_unlock_bh(&sk->sk_callback_lock); } if (!xprt_bound(xprt)) return -ENOTCONN; /* Tell the socket layer to start connecting... */ xprt->stat.connect_count++; xprt->stat.connect_start = jiffies; return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK); } /** * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint * @xprt: RPC transport to connect * @transport: socket transport to connect * @create_sock: function to create a socket of the correct type * * Invoked by a work queue tasklet. */ static void xs_tcp_setup_socket(struct work_struct *work) { struct sock_xprt *transport = container_of(work, struct sock_xprt, connect_worker.work); struct socket *sock = transport->sock; struct rpc_xprt *xprt = &transport->xprt; int status = -EIO; if (xprt->shutdown) goto out; if (!sock) { clear_bit(XPRT_CONNECTION_ABORT, &xprt->state); sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family, SOCK_STREAM, IPPROTO_TCP); if (IS_ERR(sock)) { status = PTR_ERR(sock); goto out; } } else { int abort_and_exit; abort_and_exit = test_and_clear_bit(XPRT_CONNECTION_ABORT, &xprt->state); /* "close" the socket, preserving the local port */ xs_tcp_reuse_connection(transport); if (abort_and_exit) goto out_eagain; } dprintk("RPC: worker connecting xprt %p via %s to " "%s (port %s)\n", xprt, xprt->address_strings[RPC_DISPLAY_PROTO], xprt->address_strings[RPC_DISPLAY_ADDR], xprt->address_strings[RPC_DISPLAY_PORT]); status = xs_tcp_finish_connecting(xprt, sock); dprintk("RPC: %p connect status %d connected %d sock state %d\n", xprt, -status, xprt_connected(xprt), sock->sk->sk_state); switch (status) { default: printk("%s: connect returned unhandled error %d\n", __func__, status); case -EADDRNOTAVAIL: /* We're probably in TIME_WAIT. Get rid of existing socket, * and retry */ set_bit(XPRT_CONNECTION_CLOSE, &xprt->state); xprt_force_disconnect(xprt); break; case -ECONNREFUSED: case -ECONNRESET: case -ENETUNREACH: /* retry with existing socket, after a delay */ case 0: case -EINPROGRESS: case -EALREADY: xprt_clear_connecting(xprt); return; case -EINVAL: /* Happens, for instance, if the user specified a link * local IPv6 address without a scope-id. */ goto out; } out_eagain: status = -EAGAIN; out: xprt_clear_connecting(xprt); xprt_wake_pending_tasks(xprt, status); } /** * xs_connect - connect a socket to a remote endpoint * @task: address of RPC task that manages state of connect request * * TCP: If the remote end dropped the connection, delay reconnecting. * * UDP socket connects are synchronous, but we use a work queue anyway * to guarantee that even unprivileged user processes can set up a * socket on a privileged port. * * If a UDP socket connect fails, the delay behavior here prevents * retry floods (hard mounts). */ static void xs_connect(struct rpc_task *task) { struct rpc_xprt *xprt = task->tk_xprt; struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); if (transport->sock != NULL && !RPC_IS_SOFTCONN(task)) { dprintk("RPC: xs_connect delayed xprt %p for %lu " "seconds\n", xprt, xprt->reestablish_timeout / HZ); queue_delayed_work(rpciod_workqueue, &transport->connect_worker, xprt->reestablish_timeout); xprt->reestablish_timeout <<= 1; if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO) xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO) xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO; } else { dprintk("RPC: xs_connect scheduled xprt %p\n", xprt); queue_delayed_work(rpciod_workqueue, &transport->connect_worker, 0); } } /** * xs_udp_print_stats - display UDP socket-specifc stats * @xprt: rpc_xprt struct containing statistics * @seq: output file * */ static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %Lu %Lu\n", transport->srcport, xprt->stat.bind_count, xprt->stat.sends, xprt->stat.recvs, xprt->stat.bad_xids, xprt->stat.req_u, xprt->stat.bklog_u); } /** * xs_tcp_print_stats - display TCP socket-specifc stats * @xprt: rpc_xprt struct containing statistics * @seq: output file * */ static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq) { struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); long idle_time = 0; if (xprt_connected(xprt)) idle_time = (long)(jiffies - xprt->last_used) / HZ; seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu %Lu %Lu\n", transport->srcport, xprt->stat.bind_count, xprt->stat.connect_count, xprt->stat.connect_time, idle_time, xprt->stat.sends, xprt->stat.recvs, xprt->stat.bad_xids, xprt->stat.req_u, 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. */ static 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 */ static 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) { } /* * The xprt destroy routine. Again, because this connection is client * initiated, we do nothing */ static void bc_destroy(struct rpc_xprt *xprt) { } static struct rpc_xprt_ops xs_udp_ops = { .set_buffer_size = xs_udp_set_buffer_size, .reserve_xprt = xprt_reserve_xprt_cong, .release_xprt = xprt_release_xprt_cong, .rpcbind = rpcb_getport_async, .set_port = xs_set_port, .connect = xs_connect, .buf_alloc = rpc_malloc, .buf_free = rpc_free, .send_request = xs_udp_send_request, .set_retrans_timeout = xprt_set_retrans_timeout_rtt, .timer = xs_udp_timer, .release_request = xprt_release_rqst_cong, .close = xs_close, .destroy = xs_destroy, .print_stats = xs_udp_print_stats, }; static struct rpc_xprt_ops xs_tcp_ops = { .reserve_xprt = xprt_reserve_xprt, .release_xprt = xs_tcp_release_xprt, .rpcbind = rpcb_getport_async, .set_port = xs_set_port, .connect = xs_connect, .buf_alloc = rpc_malloc, .buf_free = rpc_free, .send_request = xs_tcp_send_request, .set_retrans_timeout = xprt_set_retrans_timeout_def, .close = xs_tcp_close, .destroy = xs_destroy, .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 int xs_init_anyaddr(const int family, struct sockaddr *sap) { static const struct sockaddr_in sin = { .sin_family = AF_INET, .sin_addr.s_addr = htonl(INADDR_ANY), }; static const struct sockaddr_in6 sin6 = { .sin6_family = AF_INET6, .sin6_addr = IN6ADDR_ANY_INIT, }; switch (family) { case AF_INET: memcpy(sap, &sin, sizeof(sin)); break; case AF_INET6: memcpy(sap, &sin6, sizeof(sin6)); break; default: dprintk("RPC: %s: Bad address family\n", __func__); return -EAFNOSUPPORT; } return 0; } static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args, unsigned int slot_table_size) { struct rpc_xprt *xprt; struct sock_xprt *new; if (args->addrlen > sizeof(xprt->addr)) { dprintk("RPC: xs_setup_xprt: address too large\n"); return ERR_PTR(-EBADF); } xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size); if (xprt == NULL) { dprintk("RPC: xs_setup_xprt: couldn't allocate " "rpc_xprt\n"); return ERR_PTR(-ENOMEM); } new = container_of(xprt, struct sock_xprt, xprt); memcpy(&xprt->addr, args->dstaddr, args->addrlen); xprt->addrlen = args->addrlen; if (args->srcaddr) memcpy(&new->srcaddr, args->srcaddr, args->addrlen); else { int err; err = xs_init_anyaddr(args->dstaddr->sa_family, (struct sockaddr *)&new->srcaddr); if (err != 0) return ERR_PTR(err); } return xprt; } static const struct rpc_timeout xs_udp_default_timeout = { .to_initval = 5 * HZ, .to_maxval = 30 * HZ, .to_increment = 5 * HZ, .to_retries = 5, }; /** * xs_setup_udp - Set up transport to use a UDP socket * @args: rpc transport creation arguments * */ static struct rpc_xprt *xs_setup_udp(struct xprt_create *args) { struct sockaddr *addr = args->dstaddr; struct rpc_xprt *xprt; struct sock_xprt *transport; struct rpc_xprt *ret; xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries); if (IS_ERR(xprt)) return xprt; transport = container_of(xprt, struct sock_xprt, xprt); xprt->prot = IPPROTO_UDP; xprt->tsh_size = 0; /* XXX: header size can vary due to auth type, IPv6, etc. */ xprt->max_payload = (1U << 16) - (MAX_HEADER << 3); xprt->bind_timeout = XS_BIND_TO; xprt->reestablish_timeout = XS_UDP_REEST_TO; xprt->idle_timeout = XS_IDLE_DISC_TO; xprt->ops = &xs_udp_ops; xprt->timeout = &xs_udp_default_timeout; switch (addr->sa_family) { case AF_INET: if (((struct sockaddr_in *)addr)->sin_port != htons(0)) xprt_set_bound(xprt); INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket); xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP); break; case AF_INET6: if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0)) xprt_set_bound(xprt); INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket); xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6); break; default: ret = ERR_PTR(-EAFNOSUPPORT); goto out_err; } if (xprt_bound(xprt)) dprintk("RPC: set up xprt to %s (port %s) via %s\n", xprt->address_strings[RPC_DISPLAY_ADDR], xprt->address_strings[RPC_DISPLAY_PORT], xprt->address_strings[RPC_DISPLAY_PROTO]); else dprintk("RPC: set up xprt to %s (autobind) via %s\n", xprt->address_strings[RPC_DISPLAY_ADDR], xprt->address_strings[RPC_DISPLAY_PROTO]); if (try_module_get(THIS_MODULE)) return xprt; ret = ERR_PTR(-EINVAL); out_err: xprt_free(xprt); return ret; } static const struct rpc_timeout xs_tcp_default_timeout = { .to_initval = 60 * HZ, .to_maxval = 60 * HZ, .to_retries = 2, }; /** * xs_setup_tcp - Set up transport to use a TCP socket * @args: rpc transport creation arguments * */ static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args) { struct sockaddr *addr = args->dstaddr; struct rpc_xprt *xprt; struct sock_xprt *transport; struct rpc_xprt *ret; xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries); if (IS_ERR(xprt)) return xprt; transport = container_of(xprt, struct sock_xprt, xprt); xprt->prot = IPPROTO_TCP; xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32); xprt->max_payload = RPC_MAX_FRAGMENT_SIZE; xprt->bind_timeout = XS_BIND_TO; xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; xprt->idle_timeout = XS_IDLE_DISC_TO; xprt->ops = &xs_tcp_ops; xprt->timeout = &xs_tcp_default_timeout; switch (addr->sa_family) { case AF_INET: if (((struct sockaddr_in *)addr)->sin_port != htons(0)) xprt_set_bound(xprt); INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket); xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP); break; case AF_INET6: if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0)) xprt_set_bound(xprt); INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket); xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6); break; default: ret = ERR_PTR(-EAFNOSUPPORT); goto out_err; } if (xprt_bound(xprt)) dprintk("RPC: set up xprt to %s (port %s) via %s\n", xprt->address_strings[RPC_DISPLAY_ADDR], xprt->address_strings[RPC_DISPLAY_PORT], xprt->address_strings[RPC_DISPLAY_PROTO]); else dprintk("RPC: set up xprt to %s (autobind) via %s\n", xprt->address_strings[RPC_DISPLAY_ADDR], xprt->address_strings[RPC_DISPLAY_PROTO]); if (try_module_get(THIS_MODULE)) return xprt; ret = ERR_PTR(-EINVAL); out_err: xprt_free(xprt); return ret; } /** * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket * @args: rpc transport creation arguments * */ static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args) { struct sockaddr *addr = args->dstaddr; struct rpc_xprt *xprt; struct sock_xprt *transport; struct svc_sock *bc_sock; struct rpc_xprt *ret; xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries); if (IS_ERR(xprt)) return xprt; transport = container_of(xprt, struct sock_xprt, xprt); xprt->prot = IPPROTO_TCP; xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32); xprt->max_payload = RPC_MAX_FRAGMENT_SIZE; xprt->timeout = &xs_tcp_default_timeout; /* backchannel */ xprt_set_bound(xprt); xprt->bind_timeout = 0; xprt->reestablish_timeout = 0; xprt->idle_timeout = 0; xprt->ops = &bc_tcp_ops; switch (addr->sa_family) { case AF_INET: xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP); break; case AF_INET6: xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6); break; default: ret = ERR_PTR(-EAFNOSUPPORT); goto out_err; } dprintk("RPC: set up xprt to %s (port %s) via %s\n", xprt->address_strings[RPC_DISPLAY_ADDR], xprt->address_strings[RPC_DISPLAY_PORT], xprt->address_strings[RPC_DISPLAY_PROTO]); /* * The backchannel uses the same socket connection as the * forechannel */ if (args->bc_xprt->xpt_bc_xprt) { /* XXX: actually, want to catch this case... */ ret = ERR_PTR(-EINVAL); goto out_err; } /* * Once we've associated a backchannel xprt with a connection, * we want to keep it around as long as long as the connection * lasts, in case we need to start using it for a backchannel * again; this reference won't be dropped until bc_xprt is * destroyed. */ xprt_get(xprt); args->bc_xprt->xpt_bc_xprt = xprt; xprt->bc_xprt = args->bc_xprt; bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt); transport->sock = bc_sock->sk_sock; transport->inet = bc_sock->sk_sk; /* * Since we don't want connections for the backchannel, we set * the xprt status to connected */ xprt_set_connected(xprt); if (try_module_get(THIS_MODULE)) return xprt; xprt_put(xprt); ret = ERR_PTR(-EINVAL); out_err: xprt_free(xprt); return ret; } static struct xprt_class xs_udp_transport = { .list = LIST_HEAD_INIT(xs_udp_transport.list), .name = "udp", .owner = THIS_MODULE, .ident = XPRT_TRANSPORT_UDP, .setup = xs_setup_udp, }; static struct xprt_class xs_tcp_transport = { .list = LIST_HEAD_INIT(xs_tcp_transport.list), .name = "tcp", .owner = THIS_MODULE, .ident = XPRT_TRANSPORT_TCP, .setup = xs_setup_tcp, }; static struct xprt_class xs_bc_tcp_transport = { .list = LIST_HEAD_INIT(xs_bc_tcp_transport.list), .name = "tcp NFSv4.1 backchannel", .owner = THIS_MODULE, .ident = XPRT_TRANSPORT_BC_TCP, .setup = xs_setup_bc_tcp, }; /** * init_socket_xprt - set up xprtsock's sysctls, register with RPC client * */ int init_socket_xprt(void) { #ifdef RPC_DEBUG if (!sunrpc_table_header) sunrpc_table_header = register_sysctl_table(sunrpc_table); #endif xprt_register_transport(&xs_udp_transport); xprt_register_transport(&xs_tcp_transport); xprt_register_transport(&xs_bc_tcp_transport); return 0; } /** * cleanup_socket_xprt - remove xprtsock's sysctls, unregister * */ void cleanup_socket_xprt(void) { #ifdef RPC_DEBUG if (sunrpc_table_header) { unregister_sysctl_table(sunrpc_table_header); sunrpc_table_header = NULL; } #endif xprt_unregister_transport(&xs_udp_transport); xprt_unregister_transport(&xs_tcp_transport); xprt_unregister_transport(&xs_bc_tcp_transport); } static int param_set_uint_minmax(const char *val, const struct kernel_param *kp, unsigned int min, unsigned int max) { unsigned long num; int ret; if (!val) return -EINVAL; ret = strict_strtoul(val, 0, &num); if (ret == -EINVAL || num < min || num > max) return -EINVAL; *((unsigned int *)kp->arg) = num; return 0; } static int param_set_portnr(const char *val, const struct kernel_param *kp) { return param_set_uint_minmax(val, kp, RPC_MIN_RESVPORT, RPC_MAX_RESVPORT); } static struct kernel_param_ops param_ops_portnr = { .set = param_set_portnr, .get = param_get_uint, }; #define param_check_portnr(name, p) \ __param_check(name, p, unsigned int); module_param_named(min_resvport, xprt_min_resvport, portnr, 0644); module_param_named(max_resvport, xprt_max_resvport, portnr, 0644); static int param_set_slot_table_size(const char *val, const struct kernel_param *kp) { return param_set_uint_minmax(val, kp, RPC_MIN_SLOT_TABLE, RPC_MAX_SLOT_TABLE); } static struct kernel_param_ops param_ops_slot_table_size = { .set = param_set_slot_table_size, .get = param_get_uint, }; #define param_check_slot_table_size(name, p) \ __param_check(name, p, unsigned int); module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries, slot_table_size, 0644); module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries, slot_table_size, 0644);