| /* |
| * linux/net/sunrpc/xprt.c |
| * |
| * This is a generic RPC call interface supporting congestion avoidance, |
| * and asynchronous calls. |
| * |
| * The interface works like this: |
| * |
| * - When a process places a call, it allocates a request slot if |
| * one is available. Otherwise, it sleeps on the backlog queue |
| * (xprt_reserve). |
| * - Next, the caller puts together the RPC message, stuffs it into |
| * the request struct, and calls xprt_call(). |
| * - xprt_call transmits the message and installs the caller on the |
| * socket's wait list. At the same time, it installs a timer that |
| * is run after the packet's timeout has expired. |
| * - When a packet arrives, the data_ready handler walks the list of |
| * pending requests for that socket. If a matching XID is found, the |
| * caller is woken up, and the timer removed. |
| * - When no reply arrives within the timeout interval, the timer is |
| * fired by the kernel and runs xprt_timer(). It either adjusts the |
| * timeout values (minor timeout) or wakes up the caller with a status |
| * of -ETIMEDOUT. |
| * - When the caller receives a notification from RPC that a reply arrived, |
| * it should release the RPC slot, and process the reply. |
| * If the call timed out, it may choose to retry the operation by |
| * adjusting the initial timeout value, and simply calling rpc_call |
| * again. |
| * |
| * Support for async RPC is done through a set of RPC-specific scheduling |
| * primitives that `transparently' work for processes as well as async |
| * tasks that rely on callbacks. |
| * |
| * Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de> |
| * |
| * TCP callback races fixes (C) 1998 Red Hat Software <alan@redhat.com> |
| * TCP send fixes (C) 1998 Red Hat Software <alan@redhat.com> |
| * TCP NFS related read + write fixes |
| * (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie> |
| * |
| * Rewrite of larges part of the code in order to stabilize TCP stuff. |
| * Fix behaviour when socket buffer is full. |
| * (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no> |
| */ |
| |
| #include <linux/types.h> |
| #include <linux/slab.h> |
| #include <linux/capability.h> |
| #include <linux/sched.h> |
| #include <linux/errno.h> |
| #include <linux/socket.h> |
| #include <linux/in.h> |
| #include <linux/net.h> |
| #include <linux/mm.h> |
| #include <linux/udp.h> |
| #include <linux/tcp.h> |
| #include <linux/sunrpc/clnt.h> |
| #include <linux/file.h> |
| #include <linux/workqueue.h> |
| #include <linux/random.h> |
| |
| #include <net/sock.h> |
| #include <net/checksum.h> |
| #include <net/udp.h> |
| #include <net/tcp.h> |
| |
| /* |
| * Local variables |
| */ |
| |
| #ifdef RPC_DEBUG |
| # undef RPC_DEBUG_DATA |
| # define RPCDBG_FACILITY RPCDBG_XPRT |
| #endif |
| |
| #define XPRT_MAX_BACKOFF (8) |
| #define XPRT_IDLE_TIMEOUT (5*60*HZ) |
| #define XPRT_MAX_RESVPORT (800) |
| |
| /* |
| * Local functions |
| */ |
| static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); |
| static inline void do_xprt_reserve(struct rpc_task *); |
| static void xprt_disconnect(struct rpc_xprt *); |
| static void xprt_connect_status(struct rpc_task *task); |
| static struct rpc_xprt * xprt_setup(int proto, struct sockaddr_in *ap, |
| struct rpc_timeout *to); |
| static struct socket *xprt_create_socket(struct rpc_xprt *, int, int); |
| static void xprt_bind_socket(struct rpc_xprt *, struct socket *); |
| static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); |
| |
| static int xprt_clear_backlog(struct rpc_xprt *xprt); |
| |
| #ifdef RPC_DEBUG_DATA |
| /* |
| * Print the buffer contents (first 128 bytes only--just enough for |
| * diropres return). |
| */ |
| static void |
| xprt_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 |
| xprt_pktdump(char *msg, u32 *packet, unsigned int count) |
| { |
| /* NOP */ |
| } |
| #endif |
| |
| /* |
| * Look up RPC transport given an INET socket |
| */ |
| static inline struct rpc_xprt * |
| xprt_from_sock(struct sock *sk) |
| { |
| return (struct rpc_xprt *) sk->sk_user_data; |
| } |
| |
| /* |
| * Serialize write access to sockets, in order to prevent different |
| * requests from interfering with each other. |
| * Also prevents TCP socket connects from colliding with writes. |
| */ |
| static int |
| __xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) |
| { |
| struct rpc_rqst *req = task->tk_rqstp; |
| |
| if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate)) { |
| if (task == xprt->snd_task) |
| return 1; |
| goto out_sleep; |
| } |
| if (xprt->nocong || __xprt_get_cong(xprt, task)) { |
| xprt->snd_task = task; |
| if (req) { |
| req->rq_bytes_sent = 0; |
| req->rq_ntrans++; |
| } |
| return 1; |
| } |
| smp_mb__before_clear_bit(); |
| clear_bit(XPRT_LOCKED, &xprt->sockstate); |
| smp_mb__after_clear_bit(); |
| out_sleep: |
| dprintk("RPC: %4d failed to lock socket %p\n", task->tk_pid, xprt); |
| task->tk_timeout = 0; |
| task->tk_status = -EAGAIN; |
| if (req && req->rq_ntrans) |
| rpc_sleep_on(&xprt->resend, task, NULL, NULL); |
| else |
| rpc_sleep_on(&xprt->sending, task, NULL, NULL); |
| return 0; |
| } |
| |
| static inline int |
| xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) |
| { |
| int retval; |
| |
| spin_lock_bh(&xprt->sock_lock); |
| retval = __xprt_lock_write(xprt, task); |
| spin_unlock_bh(&xprt->sock_lock); |
| return retval; |
| } |
| |
| |
| static void |
| __xprt_lock_write_next(struct rpc_xprt *xprt) |
| { |
| struct rpc_task *task; |
| |
| if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate)) |
| return; |
| if (!xprt->nocong && RPCXPRT_CONGESTED(xprt)) |
| goto out_unlock; |
| task = rpc_wake_up_next(&xprt->resend); |
| if (!task) { |
| task = rpc_wake_up_next(&xprt->sending); |
| if (!task) |
| goto out_unlock; |
| } |
| if (xprt->nocong || __xprt_get_cong(xprt, task)) { |
| struct rpc_rqst *req = task->tk_rqstp; |
| xprt->snd_task = task; |
| if (req) { |
| req->rq_bytes_sent = 0; |
| req->rq_ntrans++; |
| } |
| return; |
| } |
| out_unlock: |
| smp_mb__before_clear_bit(); |
| clear_bit(XPRT_LOCKED, &xprt->sockstate); |
| smp_mb__after_clear_bit(); |
| } |
| |
| /* |
| * Releases the socket for use by other requests. |
| */ |
| static void |
| __xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) |
| { |
| if (xprt->snd_task == task) { |
| xprt->snd_task = NULL; |
| smp_mb__before_clear_bit(); |
| clear_bit(XPRT_LOCKED, &xprt->sockstate); |
| smp_mb__after_clear_bit(); |
| __xprt_lock_write_next(xprt); |
| } |
| } |
| |
| static inline void |
| xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) |
| { |
| spin_lock_bh(&xprt->sock_lock); |
| __xprt_release_write(xprt, task); |
| spin_unlock_bh(&xprt->sock_lock); |
| } |
| |
| /* |
| * Write data to socket. |
| */ |
| static inline int |
| xprt_sendmsg(struct rpc_xprt *xprt, struct rpc_rqst *req) |
| { |
| struct socket *sock = xprt->sock; |
| struct xdr_buf *xdr = &req->rq_snd_buf; |
| struct sockaddr *addr = NULL; |
| int addrlen = 0; |
| unsigned int skip; |
| int result; |
| |
| if (!sock) |
| return -ENOTCONN; |
| |
| xprt_pktdump("packet data:", |
| req->rq_svec->iov_base, |
| req->rq_svec->iov_len); |
| |
| /* For UDP, we need to provide an address */ |
| if (!xprt->stream) { |
| addr = (struct sockaddr *) &xprt->addr; |
| addrlen = sizeof(xprt->addr); |
| } |
| /* Dont repeat bytes */ |
| skip = req->rq_bytes_sent; |
| |
| clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags); |
| result = xdr_sendpages(sock, addr, addrlen, xdr, skip, MSG_DONTWAIT); |
| |
| dprintk("RPC: xprt_sendmsg(%d) = %d\n", xdr->len - skip, result); |
| |
| if (result >= 0) |
| return result; |
| |
| switch (result) { |
| case -ECONNREFUSED: |
| /* When the server has died, an ICMP port unreachable message |
| * prompts ECONNREFUSED. |
| */ |
| case -EAGAIN: |
| break; |
| case -ECONNRESET: |
| case -ENOTCONN: |
| case -EPIPE: |
| /* connection broken */ |
| if (xprt->stream) |
| result = -ENOTCONN; |
| break; |
| default: |
| printk(KERN_NOTICE "RPC: sendmsg returned error %d\n", -result); |
| } |
| return result; |
| } |
| |
| /* |
| * Van Jacobson congestion avoidance. Check if the congestion window |
| * overflowed. Put the task to sleep if this is the case. |
| */ |
| static int |
| __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) |
| { |
| struct rpc_rqst *req = task->tk_rqstp; |
| |
| if (req->rq_cong) |
| return 1; |
| dprintk("RPC: %4d xprt_cwnd_limited cong = %ld cwnd = %ld\n", |
| task->tk_pid, xprt->cong, xprt->cwnd); |
| if (RPCXPRT_CONGESTED(xprt)) |
| return 0; |
| req->rq_cong = 1; |
| xprt->cong += RPC_CWNDSCALE; |
| return 1; |
| } |
| |
| /* |
| * Adjust the congestion window, and wake up the next task |
| * that has been sleeping due to congestion |
| */ |
| static void |
| __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) |
| { |
| if (!req->rq_cong) |
| return; |
| req->rq_cong = 0; |
| xprt->cong -= RPC_CWNDSCALE; |
| __xprt_lock_write_next(xprt); |
| } |
| |
| /* |
| * Adjust RPC congestion window |
| * We use a time-smoothed congestion estimator to avoid heavy oscillation. |
| */ |
| static void |
| xprt_adjust_cwnd(struct rpc_xprt *xprt, int result) |
| { |
| unsigned long cwnd; |
| |
| cwnd = xprt->cwnd; |
| if (result >= 0 && cwnd <= xprt->cong) { |
| /* The (cwnd >> 1) term makes sure |
| * the result gets rounded properly. */ |
| cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; |
| if (cwnd > RPC_MAXCWND(xprt)) |
| cwnd = RPC_MAXCWND(xprt); |
| __xprt_lock_write_next(xprt); |
| } else if (result == -ETIMEDOUT) { |
| cwnd >>= 1; |
| if (cwnd < RPC_CWNDSCALE) |
| cwnd = RPC_CWNDSCALE; |
| } |
| dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", |
| xprt->cong, xprt->cwnd, cwnd); |
| xprt->cwnd = cwnd; |
| } |
| |
| /* |
| * Reset the major timeout value |
| */ |
| static void xprt_reset_majortimeo(struct rpc_rqst *req) |
| { |
| struct rpc_timeout *to = &req->rq_xprt->timeout; |
| |
| req->rq_majortimeo = req->rq_timeout; |
| if (to->to_exponential) |
| req->rq_majortimeo <<= to->to_retries; |
| else |
| req->rq_majortimeo += to->to_increment * to->to_retries; |
| if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) |
| req->rq_majortimeo = to->to_maxval; |
| req->rq_majortimeo += jiffies; |
| } |
| |
| /* |
| * Adjust timeout values etc for next retransmit |
| */ |
| int xprt_adjust_timeout(struct rpc_rqst *req) |
| { |
| struct rpc_xprt *xprt = req->rq_xprt; |
| struct rpc_timeout *to = &xprt->timeout; |
| int status = 0; |
| |
| if (time_before(jiffies, req->rq_majortimeo)) { |
| if (to->to_exponential) |
| req->rq_timeout <<= 1; |
| else |
| req->rq_timeout += to->to_increment; |
| if (to->to_maxval && req->rq_timeout >= to->to_maxval) |
| req->rq_timeout = to->to_maxval; |
| req->rq_retries++; |
| pprintk("RPC: %lu retrans\n", jiffies); |
| } else { |
| req->rq_timeout = to->to_initval; |
| req->rq_retries = 0; |
| xprt_reset_majortimeo(req); |
| /* Reset the RTT counters == "slow start" */ |
| spin_lock_bh(&xprt->sock_lock); |
| rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); |
| spin_unlock_bh(&xprt->sock_lock); |
| pprintk("RPC: %lu timeout\n", jiffies); |
| status = -ETIMEDOUT; |
| } |
| |
| if (req->rq_timeout == 0) { |
| printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); |
| req->rq_timeout = 5 * HZ; |
| } |
| return status; |
| } |
| |
| /* |
| * Close down a transport socket |
| */ |
| static void |
| xprt_close(struct rpc_xprt *xprt) |
| { |
| struct socket *sock = xprt->sock; |
| struct sock *sk = xprt->inet; |
| |
| if (!sk) |
| return; |
| |
| write_lock_bh(&sk->sk_callback_lock); |
| xprt->inet = NULL; |
| xprt->sock = NULL; |
| |
| sk->sk_user_data = NULL; |
| sk->sk_data_ready = xprt->old_data_ready; |
| sk->sk_state_change = xprt->old_state_change; |
| sk->sk_write_space = xprt->old_write_space; |
| write_unlock_bh(&sk->sk_callback_lock); |
| |
| sk->sk_no_check = 0; |
| |
| sock_release(sock); |
| } |
| |
| static void |
| xprt_socket_autoclose(void *args) |
| { |
| struct rpc_xprt *xprt = (struct rpc_xprt *)args; |
| |
| xprt_disconnect(xprt); |
| xprt_close(xprt); |
| xprt_release_write(xprt, NULL); |
| } |
| |
| /* |
| * Mark a transport as disconnected |
| */ |
| static void |
| xprt_disconnect(struct rpc_xprt *xprt) |
| { |
| dprintk("RPC: disconnected transport %p\n", xprt); |
| spin_lock_bh(&xprt->sock_lock); |
| xprt_clear_connected(xprt); |
| rpc_wake_up_status(&xprt->pending, -ENOTCONN); |
| spin_unlock_bh(&xprt->sock_lock); |
| } |
| |
| /* |
| * Used to allow disconnection when we've been idle |
| */ |
| static void |
| xprt_init_autodisconnect(unsigned long data) |
| { |
| struct rpc_xprt *xprt = (struct rpc_xprt *)data; |
| |
| spin_lock(&xprt->sock_lock); |
| if (!list_empty(&xprt->recv) || xprt->shutdown) |
| goto out_abort; |
| if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate)) |
| goto out_abort; |
| spin_unlock(&xprt->sock_lock); |
| /* Let keventd close the socket */ |
| if (test_bit(XPRT_CONNECTING, &xprt->sockstate) != 0) |
| xprt_release_write(xprt, NULL); |
| else |
| schedule_work(&xprt->task_cleanup); |
| return; |
| out_abort: |
| spin_unlock(&xprt->sock_lock); |
| } |
| |
| static void xprt_socket_connect(void *args) |
| { |
| struct rpc_xprt *xprt = (struct rpc_xprt *)args; |
| struct socket *sock = xprt->sock; |
| int status = -EIO; |
| |
| if (xprt->shutdown || xprt->addr.sin_port == 0) |
| goto out; |
| |
| /* |
| * Start by resetting any existing state |
| */ |
| xprt_close(xprt); |
| sock = xprt_create_socket(xprt, xprt->prot, xprt->resvport); |
| if (sock == NULL) { |
| /* couldn't create socket or bind to reserved port; |
| * this is likely a permanent error, so cause an abort */ |
| goto out; |
| } |
| xprt_bind_socket(xprt, sock); |
| xprt_sock_setbufsize(xprt); |
| |
| status = 0; |
| if (!xprt->stream) |
| goto out; |
| |
| /* |
| * Tell the socket layer to start connecting... |
| */ |
| status = sock->ops->connect(sock, (struct sockaddr *) &xprt->addr, |
| sizeof(xprt->addr), O_NONBLOCK); |
| dprintk("RPC: %p connect status %d connected %d sock state %d\n", |
| xprt, -status, xprt_connected(xprt), sock->sk->sk_state); |
| if (status < 0) { |
| switch (status) { |
| case -EINPROGRESS: |
| case -EALREADY: |
| goto out_clear; |
| } |
| } |
| out: |
| if (status < 0) |
| rpc_wake_up_status(&xprt->pending, status); |
| else |
| rpc_wake_up(&xprt->pending); |
| out_clear: |
| smp_mb__before_clear_bit(); |
| clear_bit(XPRT_CONNECTING, &xprt->sockstate); |
| smp_mb__after_clear_bit(); |
| } |
| |
| /* |
| * Attempt to connect a TCP socket. |
| * |
| */ |
| void xprt_connect(struct rpc_task *task) |
| { |
| struct rpc_xprt *xprt = task->tk_xprt; |
| |
| dprintk("RPC: %4d xprt_connect xprt %p %s connected\n", task->tk_pid, |
| xprt, (xprt_connected(xprt) ? "is" : "is not")); |
| |
| if (xprt->shutdown) { |
| task->tk_status = -EIO; |
| return; |
| } |
| if (!xprt->addr.sin_port) { |
| task->tk_status = -EIO; |
| return; |
| } |
| if (!xprt_lock_write(xprt, task)) |
| return; |
| if (xprt_connected(xprt)) |
| goto out_write; |
| |
| if (task->tk_rqstp) |
| task->tk_rqstp->rq_bytes_sent = 0; |
| |
| task->tk_timeout = RPC_CONNECT_TIMEOUT; |
| rpc_sleep_on(&xprt->pending, task, xprt_connect_status, NULL); |
| if (!test_and_set_bit(XPRT_CONNECTING, &xprt->sockstate)) { |
| /* Note: if we are here due to a dropped connection |
| * we delay reconnecting by RPC_REESTABLISH_TIMEOUT/HZ |
| * seconds |
| */ |
| if (xprt->sock != NULL) |
| schedule_delayed_work(&xprt->sock_connect, |
| RPC_REESTABLISH_TIMEOUT); |
| else { |
| schedule_work(&xprt->sock_connect); |
| if (!RPC_IS_ASYNC(task)) |
| flush_scheduled_work(); |
| } |
| } |
| return; |
| out_write: |
| xprt_release_write(xprt, task); |
| } |
| |
| /* |
| * We arrive here when awoken from waiting on connection establishment. |
| */ |
| static void |
| xprt_connect_status(struct rpc_task *task) |
| { |
| struct rpc_xprt *xprt = task->tk_xprt; |
| |
| if (task->tk_status >= 0) { |
| dprintk("RPC: %4d xprt_connect_status: connection established\n", |
| task->tk_pid); |
| return; |
| } |
| |
| switch (task->tk_status) { |
| case -ECONNREFUSED: |
| case -ECONNRESET: |
| dprintk("RPC: %4d xprt_connect_status: server %s refused connection\n", |
| task->tk_pid, task->tk_client->cl_server); |
| break; |
| case -ENOTCONN: |
| dprintk("RPC: %4d xprt_connect_status: connection broken\n", |
| task->tk_pid); |
| break; |
| case -ETIMEDOUT: |
| dprintk("RPC: %4d xprt_connect_status: connect attempt timed out\n", |
| task->tk_pid); |
| break; |
| default: |
| dprintk("RPC: %4d xprt_connect_status: error %d connecting to server %s\n", |
| task->tk_pid, -task->tk_status, task->tk_client->cl_server); |
| xprt_release_write(xprt, task); |
| task->tk_status = -EIO; |
| return; |
| } |
| |
| /* if soft mounted, just cause this RPC to fail */ |
| if (RPC_IS_SOFT(task)) { |
| xprt_release_write(xprt, task); |
| task->tk_status = -EIO; |
| } |
| } |
| |
| /* |
| * Look up the RPC request corresponding to a reply, and then lock it. |
| */ |
| static inline struct rpc_rqst * |
| xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid) |
| { |
| struct list_head *pos; |
| struct rpc_rqst *req = NULL; |
| |
| list_for_each(pos, &xprt->recv) { |
| struct rpc_rqst *entry = list_entry(pos, struct rpc_rqst, rq_list); |
| if (entry->rq_xid == xid) { |
| req = entry; |
| break; |
| } |
| } |
| return req; |
| } |
| |
| /* |
| * Complete reply received. |
| * The TCP code relies on us to remove the request from xprt->pending. |
| */ |
| static void |
| xprt_complete_rqst(struct rpc_xprt *xprt, struct rpc_rqst *req, int copied) |
| { |
| struct rpc_task *task = req->rq_task; |
| struct rpc_clnt *clnt = task->tk_client; |
| |
| /* Adjust congestion window */ |
| if (!xprt->nocong) { |
| unsigned timer = task->tk_msg.rpc_proc->p_timer; |
| xprt_adjust_cwnd(xprt, copied); |
| __xprt_put_cong(xprt, req); |
| if (timer) { |
| if (req->rq_ntrans == 1) |
| rpc_update_rtt(clnt->cl_rtt, timer, |
| (long)jiffies - req->rq_xtime); |
| rpc_set_timeo(clnt->cl_rtt, timer, req->rq_ntrans - 1); |
| } |
| } |
| |
| #ifdef RPC_PROFILE |
| /* Profile only reads for now */ |
| if (copied > 1024) { |
| static unsigned long nextstat; |
| static unsigned long pkt_rtt, pkt_len, pkt_cnt; |
| |
| pkt_cnt++; |
| pkt_len += req->rq_slen + copied; |
| pkt_rtt += jiffies - req->rq_xtime; |
| if (time_before(nextstat, jiffies)) { |
| printk("RPC: %lu %ld cwnd\n", jiffies, xprt->cwnd); |
| printk("RPC: %ld %ld %ld %ld stat\n", |
| jiffies, pkt_cnt, pkt_len, pkt_rtt); |
| pkt_rtt = pkt_len = pkt_cnt = 0; |
| nextstat = jiffies + 5 * HZ; |
| } |
| } |
| #endif |
| |
| dprintk("RPC: %4d has input (%d bytes)\n", task->tk_pid, copied); |
| list_del_init(&req->rq_list); |
| req->rq_received = req->rq_private_buf.len = copied; |
| |
| /* ... and wake up the process. */ |
| rpc_wake_up_task(task); |
| return; |
| } |
| |
| /* |
| * Input handler for RPC replies. Called from a bottom half and hence |
| * atomic. |
| */ |
| static void |
| 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, *xp; |
| |
| read_lock(&sk->sk_callback_lock); |
| dprintk("RPC: udp_data_ready...\n"); |
| if (!(xprt = xprt_from_sock(sk))) { |
| printk("RPC: udp_data_ready request not found!\n"); |
| goto out; |
| } |
| |
| dprintk("RPC: udp_data_ready client %p\n", xprt); |
| |
| 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) { |
| printk("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->sock_lock); |
| rovr = xprt_lookup_rqst(xprt, *xp); |
| if (!rovr) |
| goto out_unlock; |
| task = rovr->rq_task; |
| |
| dprintk("RPC: %4d received reply\n", task->tk_pid); |
| |
| 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)) |
| goto out_unlock; |
| |
| /* Something worked... */ |
| dst_confirm(skb->dst); |
| |
| xprt_complete_rqst(xprt, rovr, copied); |
| |
| out_unlock: |
| spin_unlock(&xprt->sock_lock); |
| dropit: |
| skb_free_datagram(sk, skb); |
| out: |
| read_unlock(&sk->sk_callback_lock); |
| } |
| |
| /* |
| * Copy from an skb into memory and shrink the skb. |
| */ |
| static inline size_t |
| tcp_copy_data(skb_reader_t *desc, void *p, size_t len) |
| { |
| if (len > desc->count) |
| len = desc->count; |
| if (skb_copy_bits(desc->skb, desc->offset, p, len)) { |
| dprintk("RPC: failed to copy %zu bytes from skb. %zu bytes remain\n", |
| len, desc->count); |
| return 0; |
| } |
| desc->offset += len; |
| desc->count -= len; |
| dprintk("RPC: copied %zu bytes from skb. %zu bytes remain\n", |
| len, desc->count); |
| return len; |
| } |
| |
| /* |
| * TCP read fragment marker |
| */ |
| static inline void |
| tcp_read_fraghdr(struct rpc_xprt *xprt, skb_reader_t *desc) |
| { |
| size_t len, used; |
| char *p; |
| |
| p = ((char *) &xprt->tcp_recm) + xprt->tcp_offset; |
| len = sizeof(xprt->tcp_recm) - xprt->tcp_offset; |
| used = tcp_copy_data(desc, p, len); |
| xprt->tcp_offset += used; |
| if (used != len) |
| return; |
| xprt->tcp_reclen = ntohl(xprt->tcp_recm); |
| if (xprt->tcp_reclen & 0x80000000) |
| xprt->tcp_flags |= XPRT_LAST_FRAG; |
| else |
| xprt->tcp_flags &= ~XPRT_LAST_FRAG; |
| xprt->tcp_reclen &= 0x7fffffff; |
| xprt->tcp_flags &= ~XPRT_COPY_RECM; |
| xprt->tcp_offset = 0; |
| /* Sanity check of the record length */ |
| if (xprt->tcp_reclen < 4) { |
| printk(KERN_ERR "RPC: Invalid TCP record fragment length\n"); |
| xprt_disconnect(xprt); |
| } |
| dprintk("RPC: reading TCP record fragment of length %d\n", |
| xprt->tcp_reclen); |
| } |
| |
| static void |
| tcp_check_recm(struct rpc_xprt *xprt) |
| { |
| dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u, tcp_flags = %lx\n", |
| xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen, xprt->tcp_flags); |
| if (xprt->tcp_offset == xprt->tcp_reclen) { |
| xprt->tcp_flags |= XPRT_COPY_RECM; |
| xprt->tcp_offset = 0; |
| if (xprt->tcp_flags & XPRT_LAST_FRAG) { |
| xprt->tcp_flags &= ~XPRT_COPY_DATA; |
| xprt->tcp_flags |= XPRT_COPY_XID; |
| xprt->tcp_copied = 0; |
| } |
| } |
| } |
| |
| /* |
| * TCP read xid |
| */ |
| static inline void |
| tcp_read_xid(struct rpc_xprt *xprt, skb_reader_t *desc) |
| { |
| size_t len, used; |
| char *p; |
| |
| len = sizeof(xprt->tcp_xid) - xprt->tcp_offset; |
| dprintk("RPC: reading XID (%Zu bytes)\n", len); |
| p = ((char *) &xprt->tcp_xid) + xprt->tcp_offset; |
| used = tcp_copy_data(desc, p, len); |
| xprt->tcp_offset += used; |
| if (used != len) |
| return; |
| xprt->tcp_flags &= ~XPRT_COPY_XID; |
| xprt->tcp_flags |= XPRT_COPY_DATA; |
| xprt->tcp_copied = 4; |
| dprintk("RPC: reading reply for XID %08x\n", |
| ntohl(xprt->tcp_xid)); |
| tcp_check_recm(xprt); |
| } |
| |
| /* |
| * TCP read and complete request |
| */ |
| static inline void |
| tcp_read_request(struct rpc_xprt *xprt, skb_reader_t *desc) |
| { |
| struct rpc_rqst *req; |
| struct xdr_buf *rcvbuf; |
| size_t len; |
| ssize_t r; |
| |
| /* Find and lock the request corresponding to this xid */ |
| spin_lock(&xprt->sock_lock); |
| req = xprt_lookup_rqst(xprt, xprt->tcp_xid); |
| if (!req) { |
| xprt->tcp_flags &= ~XPRT_COPY_DATA; |
| dprintk("RPC: XID %08x request not found!\n", |
| ntohl(xprt->tcp_xid)); |
| spin_unlock(&xprt->sock_lock); |
| return; |
| } |
| |
| rcvbuf = &req->rq_private_buf; |
| len = desc->count; |
| if (len > xprt->tcp_reclen - xprt->tcp_offset) { |
| skb_reader_t my_desc; |
| |
| len = xprt->tcp_reclen - xprt->tcp_offset; |
| memcpy(&my_desc, desc, sizeof(my_desc)); |
| my_desc.count = len; |
| r = xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied, |
| &my_desc, tcp_copy_data); |
| desc->count -= r; |
| desc->offset += r; |
| } else |
| r = xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied, |
| desc, tcp_copy_data); |
| |
| if (r > 0) { |
| xprt->tcp_copied += r; |
| xprt->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 XPRT_COPY_DATA, so the request |
| * will not receive any additional updates, |
| * and time out. |
| * Any remaining data from this record will |
| * be discarded. |
| */ |
| xprt->tcp_flags &= ~XPRT_COPY_DATA; |
| dprintk("RPC: XID %08x truncated request\n", |
| ntohl(xprt->tcp_xid)); |
| dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n", |
| xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen); |
| goto out; |
| } |
| |
| dprintk("RPC: XID %08x read %Zd bytes\n", |
| ntohl(xprt->tcp_xid), r); |
| dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n", |
| xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen); |
| |
| if (xprt->tcp_copied == req->rq_private_buf.buflen) |
| xprt->tcp_flags &= ~XPRT_COPY_DATA; |
| else if (xprt->tcp_offset == xprt->tcp_reclen) { |
| if (xprt->tcp_flags & XPRT_LAST_FRAG) |
| xprt->tcp_flags &= ~XPRT_COPY_DATA; |
| } |
| |
| out: |
| if (!(xprt->tcp_flags & XPRT_COPY_DATA)) { |
| dprintk("RPC: %4d received reply complete\n", |
| req->rq_task->tk_pid); |
| xprt_complete_rqst(xprt, req, xprt->tcp_copied); |
| } |
| spin_unlock(&xprt->sock_lock); |
| tcp_check_recm(xprt); |
| } |
| |
| /* |
| * TCP discard extra bytes from a short read |
| */ |
| static inline void |
| tcp_read_discard(struct rpc_xprt *xprt, skb_reader_t *desc) |
| { |
| size_t len; |
| |
| len = xprt->tcp_reclen - xprt->tcp_offset; |
| if (len > desc->count) |
| len = desc->count; |
| desc->count -= len; |
| desc->offset += len; |
| xprt->tcp_offset += len; |
| dprintk("RPC: discarded %Zu bytes\n", len); |
| tcp_check_recm(xprt); |
| } |
| |
| /* |
| * TCP record receive routine |
| * We first have to grab the record marker, then the XID, then the data. |
| */ |
| static int |
| 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; |
| skb_reader_t desc = { |
| .skb = skb, |
| .offset = offset, |
| .count = len, |
| .csum = 0 |
| }; |
| |
| dprintk("RPC: tcp_data_recv\n"); |
| do { |
| /* Read in a new fragment marker if necessary */ |
| /* Can we ever really expect to get completely empty fragments? */ |
| if (xprt->tcp_flags & XPRT_COPY_RECM) { |
| tcp_read_fraghdr(xprt, &desc); |
| continue; |
| } |
| /* Read in the xid if necessary */ |
| if (xprt->tcp_flags & XPRT_COPY_XID) { |
| tcp_read_xid(xprt, &desc); |
| continue; |
| } |
| /* Read in the request data */ |
| if (xprt->tcp_flags & XPRT_COPY_DATA) { |
| tcp_read_request(xprt, &desc); |
| continue; |
| } |
| /* Skip over any trailing bytes on short reads */ |
| tcp_read_discard(xprt, &desc); |
| } while (desc.count); |
| dprintk("RPC: tcp_data_recv done\n"); |
| return len - desc.count; |
| } |
| |
| static void tcp_data_ready(struct sock *sk, int bytes) |
| { |
| struct rpc_xprt *xprt; |
| read_descriptor_t rd_desc; |
| |
| read_lock(&sk->sk_callback_lock); |
| dprintk("RPC: tcp_data_ready...\n"); |
| if (!(xprt = xprt_from_sock(sk))) { |
| printk("RPC: tcp_data_ready socket info not found!\n"); |
| goto out; |
| } |
| if (xprt->shutdown) |
| goto out; |
| |
| /* We use rd_desc to pass struct xprt to tcp_data_recv */ |
| rd_desc.arg.data = xprt; |
| rd_desc.count = 65536; |
| tcp_read_sock(sk, &rd_desc, tcp_data_recv); |
| out: |
| read_unlock(&sk->sk_callback_lock); |
| } |
| |
| static void |
| tcp_state_change(struct sock *sk) |
| { |
| struct rpc_xprt *xprt; |
| |
| read_lock(&sk->sk_callback_lock); |
| if (!(xprt = xprt_from_sock(sk))) |
| goto out; |
| dprintk("RPC: tcp_state_change client %p...\n", xprt); |
| dprintk("RPC: state %x conn %d dead %d zapped %d\n", |
| sk->sk_state, xprt_connected(xprt), |
| sock_flag(sk, SOCK_DEAD), |
| sock_flag(sk, SOCK_ZAPPED)); |
| |
| switch (sk->sk_state) { |
| case TCP_ESTABLISHED: |
| spin_lock_bh(&xprt->sock_lock); |
| if (!xprt_test_and_set_connected(xprt)) { |
| /* Reset TCP record info */ |
| xprt->tcp_offset = 0; |
| xprt->tcp_reclen = 0; |
| xprt->tcp_copied = 0; |
| xprt->tcp_flags = XPRT_COPY_RECM | XPRT_COPY_XID; |
| rpc_wake_up(&xprt->pending); |
| } |
| spin_unlock_bh(&xprt->sock_lock); |
| break; |
| case TCP_SYN_SENT: |
| case TCP_SYN_RECV: |
| break; |
| default: |
| xprt_disconnect(xprt); |
| break; |
| } |
| out: |
| read_unlock(&sk->sk_callback_lock); |
| } |
| |
| /* |
| * 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 sock_sendmsg |
| * with a bunch of small requests. |
| */ |
| static void |
| xprt_write_space(struct sock *sk) |
| { |
| struct rpc_xprt *xprt; |
| struct socket *sock; |
| |
| read_lock(&sk->sk_callback_lock); |
| if (!(xprt = xprt_from_sock(sk)) || !(sock = sk->sk_socket)) |
| goto out; |
| if (xprt->shutdown) |
| goto out; |
| |
| /* Wait until we have enough socket memory */ |
| if (xprt->stream) { |
| /* from net/core/stream.c:sk_stream_write_space */ |
| if (sk_stream_wspace(sk) < sk_stream_min_wspace(sk)) |
| goto out; |
| } else { |
| /* from net/core/sock.c:sock_def_write_space */ |
| if (!sock_writeable(sk)) |
| goto out; |
| } |
| |
| if (!test_and_clear_bit(SOCK_NOSPACE, &sock->flags)) |
| goto out; |
| |
| spin_lock_bh(&xprt->sock_lock); |
| if (xprt->snd_task) |
| rpc_wake_up_task(xprt->snd_task); |
| spin_unlock_bh(&xprt->sock_lock); |
| out: |
| read_unlock(&sk->sk_callback_lock); |
| } |
| |
| /* |
| * RPC receive timeout handler. |
| */ |
| static void |
| xprt_timer(struct rpc_task *task) |
| { |
| struct rpc_rqst *req = task->tk_rqstp; |
| struct rpc_xprt *xprt = req->rq_xprt; |
| |
| spin_lock(&xprt->sock_lock); |
| if (req->rq_received) |
| goto out; |
| |
| xprt_adjust_cwnd(req->rq_xprt, -ETIMEDOUT); |
| __xprt_put_cong(xprt, req); |
| |
| dprintk("RPC: %4d xprt_timer (%s request)\n", |
| task->tk_pid, req ? "pending" : "backlogged"); |
| |
| task->tk_status = -ETIMEDOUT; |
| out: |
| task->tk_timeout = 0; |
| rpc_wake_up_task(task); |
| spin_unlock(&xprt->sock_lock); |
| } |
| |
| /* |
| * Place the actual RPC call. |
| * We have to copy the iovec because sendmsg fiddles with its contents. |
| */ |
| int |
| xprt_prepare_transmit(struct rpc_task *task) |
| { |
| struct rpc_rqst *req = task->tk_rqstp; |
| struct rpc_xprt *xprt = req->rq_xprt; |
| int err = 0; |
| |
| dprintk("RPC: %4d xprt_prepare_transmit\n", task->tk_pid); |
| |
| if (xprt->shutdown) |
| return -EIO; |
| |
| spin_lock_bh(&xprt->sock_lock); |
| if (req->rq_received && !req->rq_bytes_sent) { |
| err = req->rq_received; |
| goto out_unlock; |
| } |
| if (!__xprt_lock_write(xprt, task)) { |
| err = -EAGAIN; |
| goto out_unlock; |
| } |
| |
| if (!xprt_connected(xprt)) { |
| err = -ENOTCONN; |
| goto out_unlock; |
| } |
| out_unlock: |
| spin_unlock_bh(&xprt->sock_lock); |
| return err; |
| } |
| |
| void |
| xprt_transmit(struct rpc_task *task) |
| { |
| struct rpc_clnt *clnt = task->tk_client; |
| struct rpc_rqst *req = task->tk_rqstp; |
| struct rpc_xprt *xprt = req->rq_xprt; |
| int status, retry = 0; |
| |
| |
| dprintk("RPC: %4d xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); |
| |
| /* set up everything as needed. */ |
| /* Write the record marker */ |
| if (xprt->stream) { |
| u32 *marker = req->rq_svec[0].iov_base; |
| |
| *marker = htonl(0x80000000|(req->rq_slen-sizeof(*marker))); |
| } |
| |
| smp_rmb(); |
| if (!req->rq_received) { |
| if (list_empty(&req->rq_list)) { |
| spin_lock_bh(&xprt->sock_lock); |
| /* Update the softirq receive buffer */ |
| memcpy(&req->rq_private_buf, &req->rq_rcv_buf, |
| sizeof(req->rq_private_buf)); |
| /* Add request to the receive list */ |
| list_add_tail(&req->rq_list, &xprt->recv); |
| spin_unlock_bh(&xprt->sock_lock); |
| xprt_reset_majortimeo(req); |
| /* Turn off autodisconnect */ |
| del_singleshot_timer_sync(&xprt->timer); |
| } |
| } else if (!req->rq_bytes_sent) |
| return; |
| |
| /* Continue transmitting the packet/record. We must be careful |
| * to cope with writespace callbacks arriving _after_ we have |
| * called xprt_sendmsg(). |
| */ |
| while (1) { |
| req->rq_xtime = jiffies; |
| status = xprt_sendmsg(xprt, req); |
| |
| if (status < 0) |
| break; |
| |
| if (xprt->stream) { |
| req->rq_bytes_sent += status; |
| |
| /* If we've sent the entire packet, immediately |
| * reset the count of bytes sent. */ |
| if (req->rq_bytes_sent >= req->rq_slen) { |
| req->rq_bytes_sent = 0; |
| goto out_receive; |
| } |
| } else { |
| if (status >= req->rq_slen) |
| goto out_receive; |
| status = -EAGAIN; |
| break; |
| } |
| |
| dprintk("RPC: %4d xmit incomplete (%d left of %d)\n", |
| task->tk_pid, req->rq_slen - req->rq_bytes_sent, |
| req->rq_slen); |
| |
| status = -EAGAIN; |
| if (retry++ > 50) |
| break; |
| } |
| |
| /* Note: at this point, task->tk_sleeping has not yet been set, |
| * hence there is no danger of the waking up task being put on |
| * schedq, and being picked up by a parallel run of rpciod(). |
| */ |
| task->tk_status = status; |
| |
| switch (status) { |
| case -EAGAIN: |
| if (test_bit(SOCK_ASYNC_NOSPACE, &xprt->sock->flags)) { |
| /* Protect against races with xprt_write_space */ |
| spin_lock_bh(&xprt->sock_lock); |
| /* Don't race with disconnect */ |
| if (!xprt_connected(xprt)) |
| task->tk_status = -ENOTCONN; |
| else if (test_bit(SOCK_NOSPACE, &xprt->sock->flags)) { |
| task->tk_timeout = req->rq_timeout; |
| rpc_sleep_on(&xprt->pending, task, NULL, NULL); |
| } |
| spin_unlock_bh(&xprt->sock_lock); |
| return; |
| } |
| /* Keep holding the socket if it is blocked */ |
| rpc_delay(task, HZ>>4); |
| return; |
| case -ECONNREFUSED: |
| task->tk_timeout = RPC_REESTABLISH_TIMEOUT; |
| rpc_sleep_on(&xprt->sending, task, NULL, NULL); |
| case -ENOTCONN: |
| return; |
| default: |
| if (xprt->stream) |
| xprt_disconnect(xprt); |
| } |
| xprt_release_write(xprt, task); |
| return; |
| out_receive: |
| dprintk("RPC: %4d xmit complete\n", task->tk_pid); |
| /* Set the task's receive timeout value */ |
| spin_lock_bh(&xprt->sock_lock); |
| if (!xprt->nocong) { |
| int timer = task->tk_msg.rpc_proc->p_timer; |
| task->tk_timeout = rpc_calc_rto(clnt->cl_rtt, timer); |
| task->tk_timeout <<= rpc_ntimeo(clnt->cl_rtt, timer) + req->rq_retries; |
| if (task->tk_timeout > xprt->timeout.to_maxval || task->tk_timeout == 0) |
| task->tk_timeout = xprt->timeout.to_maxval; |
| } else |
| task->tk_timeout = req->rq_timeout; |
| /* Don't race with disconnect */ |
| if (!xprt_connected(xprt)) |
| task->tk_status = -ENOTCONN; |
| else if (!req->rq_received) |
| rpc_sleep_on(&xprt->pending, task, NULL, xprt_timer); |
| __xprt_release_write(xprt, task); |
| spin_unlock_bh(&xprt->sock_lock); |
| } |
| |
| /* |
| * Reserve an RPC call slot. |
| */ |
| static inline void |
| do_xprt_reserve(struct rpc_task *task) |
| { |
| struct rpc_xprt *xprt = task->tk_xprt; |
| |
| task->tk_status = 0; |
| if (task->tk_rqstp) |
| return; |
| if (!list_empty(&xprt->free)) { |
| struct rpc_rqst *req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); |
| list_del_init(&req->rq_list); |
| task->tk_rqstp = req; |
| xprt_request_init(task, xprt); |
| return; |
| } |
| dprintk("RPC: waiting for request slot\n"); |
| task->tk_status = -EAGAIN; |
| task->tk_timeout = 0; |
| rpc_sleep_on(&xprt->backlog, task, NULL, NULL); |
| } |
| |
| void |
| xprt_reserve(struct rpc_task *task) |
| { |
| struct rpc_xprt *xprt = task->tk_xprt; |
| |
| task->tk_status = -EIO; |
| if (!xprt->shutdown) { |
| spin_lock(&xprt->xprt_lock); |
| do_xprt_reserve(task); |
| spin_unlock(&xprt->xprt_lock); |
| } |
| } |
| |
| /* |
| * Allocate a 'unique' XID |
| */ |
| static inline u32 xprt_alloc_xid(struct rpc_xprt *xprt) |
| { |
| return xprt->xid++; |
| } |
| |
| static inline void xprt_init_xid(struct rpc_xprt *xprt) |
| { |
| get_random_bytes(&xprt->xid, sizeof(xprt->xid)); |
| } |
| |
| /* |
| * Initialize RPC request |
| */ |
| static void |
| xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) |
| { |
| struct rpc_rqst *req = task->tk_rqstp; |
| |
| req->rq_timeout = xprt->timeout.to_initval; |
| req->rq_task = task; |
| req->rq_xprt = xprt; |
| req->rq_xid = xprt_alloc_xid(xprt); |
| dprintk("RPC: %4d reserved req %p xid %08x\n", task->tk_pid, |
| req, ntohl(req->rq_xid)); |
| } |
| |
| /* |
| * Release an RPC call slot |
| */ |
| void |
| xprt_release(struct rpc_task *task) |
| { |
| struct rpc_xprt *xprt = task->tk_xprt; |
| struct rpc_rqst *req; |
| |
| if (!(req = task->tk_rqstp)) |
| return; |
| spin_lock_bh(&xprt->sock_lock); |
| __xprt_release_write(xprt, task); |
| __xprt_put_cong(xprt, req); |
| if (!list_empty(&req->rq_list)) |
| list_del(&req->rq_list); |
| xprt->last_used = jiffies; |
| if (list_empty(&xprt->recv) && !xprt->shutdown) |
| mod_timer(&xprt->timer, xprt->last_used + XPRT_IDLE_TIMEOUT); |
| spin_unlock_bh(&xprt->sock_lock); |
| task->tk_rqstp = NULL; |
| memset(req, 0, sizeof(*req)); /* mark unused */ |
| |
| dprintk("RPC: %4d release request %p\n", task->tk_pid, req); |
| |
| spin_lock(&xprt->xprt_lock); |
| list_add(&req->rq_list, &xprt->free); |
| xprt_clear_backlog(xprt); |
| spin_unlock(&xprt->xprt_lock); |
| } |
| |
| /* |
| * Set default timeout parameters |
| */ |
| static void |
| xprt_default_timeout(struct rpc_timeout *to, int proto) |
| { |
| if (proto == IPPROTO_UDP) |
| xprt_set_timeout(to, 5, 5 * HZ); |
| else |
| xprt_set_timeout(to, 2, 60 * HZ); |
| } |
| |
| /* |
| * Set constant timeout |
| */ |
| void |
| xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr) |
| { |
| to->to_initval = |
| to->to_increment = incr; |
| to->to_maxval = to->to_initval + (incr * retr); |
| to->to_retries = retr; |
| to->to_exponential = 0; |
| } |
| |
| unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE; |
| unsigned int xprt_tcp_slot_table_entries = RPC_DEF_SLOT_TABLE; |
| |
| /* |
| * Initialize an RPC client |
| */ |
| static struct rpc_xprt * |
| xprt_setup(int proto, struct sockaddr_in *ap, struct rpc_timeout *to) |
| { |
| struct rpc_xprt *xprt; |
| unsigned int entries; |
| size_t slot_table_size; |
| struct rpc_rqst *req; |
| |
| dprintk("RPC: setting up %s transport...\n", |
| proto == IPPROTO_UDP? "UDP" : "TCP"); |
| |
| entries = (proto == IPPROTO_TCP)? |
| xprt_tcp_slot_table_entries : xprt_udp_slot_table_entries; |
| |
| if ((xprt = kmalloc(sizeof(struct rpc_xprt), GFP_KERNEL)) == NULL) |
| return ERR_PTR(-ENOMEM); |
| memset(xprt, 0, sizeof(*xprt)); /* Nnnngh! */ |
| xprt->max_reqs = entries; |
| slot_table_size = entries * sizeof(xprt->slot[0]); |
| xprt->slot = kmalloc(slot_table_size, GFP_KERNEL); |
| if (xprt->slot == NULL) { |
| kfree(xprt); |
| return ERR_PTR(-ENOMEM); |
| } |
| memset(xprt->slot, 0, slot_table_size); |
| |
| xprt->addr = *ap; |
| xprt->prot = proto; |
| xprt->stream = (proto == IPPROTO_TCP)? 1 : 0; |
| if (xprt->stream) { |
| xprt->cwnd = RPC_MAXCWND(xprt); |
| xprt->nocong = 1; |
| xprt->max_payload = (1U << 31) - 1; |
| } else { |
| xprt->cwnd = RPC_INITCWND; |
| xprt->max_payload = (1U << 16) - (MAX_HEADER << 3); |
| } |
| spin_lock_init(&xprt->sock_lock); |
| spin_lock_init(&xprt->xprt_lock); |
| init_waitqueue_head(&xprt->cong_wait); |
| |
| INIT_LIST_HEAD(&xprt->free); |
| INIT_LIST_HEAD(&xprt->recv); |
| INIT_WORK(&xprt->sock_connect, xprt_socket_connect, xprt); |
| INIT_WORK(&xprt->task_cleanup, xprt_socket_autoclose, xprt); |
| init_timer(&xprt->timer); |
| xprt->timer.function = xprt_init_autodisconnect; |
| xprt->timer.data = (unsigned long) xprt; |
| xprt->last_used = jiffies; |
| xprt->port = XPRT_MAX_RESVPORT; |
| |
| /* Set timeout parameters */ |
| if (to) { |
| xprt->timeout = *to; |
| } else |
| xprt_default_timeout(&xprt->timeout, xprt->prot); |
| |
| rpc_init_wait_queue(&xprt->pending, "xprt_pending"); |
| rpc_init_wait_queue(&xprt->sending, "xprt_sending"); |
| rpc_init_wait_queue(&xprt->resend, "xprt_resend"); |
| rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); |
| |
| /* initialize free list */ |
| for (req = &xprt->slot[entries-1]; req >= &xprt->slot[0]; req--) |
| list_add(&req->rq_list, &xprt->free); |
| |
| xprt_init_xid(xprt); |
| |
| /* Check whether we want to use a reserved port */ |
| xprt->resvport = capable(CAP_NET_BIND_SERVICE) ? 1 : 0; |
| |
| dprintk("RPC: created transport %p with %u slots\n", xprt, |
| xprt->max_reqs); |
| |
| return xprt; |
| } |
| |
| /* |
| * Bind to a reserved port |
| */ |
| static inline int xprt_bindresvport(struct rpc_xprt *xprt, struct socket *sock) |
| { |
| struct sockaddr_in myaddr = { |
| .sin_family = AF_INET, |
| }; |
| int err, port; |
| |
| /* Were we already bound to a given port? Try to reuse it */ |
| port = xprt->port; |
| do { |
| myaddr.sin_port = htons(port); |
| err = sock->ops->bind(sock, (struct sockaddr *) &myaddr, |
| sizeof(myaddr)); |
| if (err == 0) { |
| xprt->port = port; |
| return 0; |
| } |
| if (--port == 0) |
| port = XPRT_MAX_RESVPORT; |
| } while (err == -EADDRINUSE && port != xprt->port); |
| |
| printk("RPC: Can't bind to reserved port (%d).\n", -err); |
| return err; |
| } |
| |
| static void |
| xprt_bind_socket(struct rpc_xprt *xprt, struct socket *sock) |
| { |
| struct sock *sk = sock->sk; |
| |
| if (xprt->inet) |
| return; |
| |
| write_lock_bh(&sk->sk_callback_lock); |
| sk->sk_user_data = xprt; |
| xprt->old_data_ready = sk->sk_data_ready; |
| xprt->old_state_change = sk->sk_state_change; |
| xprt->old_write_space = sk->sk_write_space; |
| if (xprt->prot == IPPROTO_UDP) { |
| sk->sk_data_ready = udp_data_ready; |
| sk->sk_no_check = UDP_CSUM_NORCV; |
| xprt_set_connected(xprt); |
| } else { |
| tcp_sk(sk)->nonagle = 1; /* disable Nagle's algorithm */ |
| sk->sk_data_ready = tcp_data_ready; |
| sk->sk_state_change = tcp_state_change; |
| xprt_clear_connected(xprt); |
| } |
| sk->sk_write_space = xprt_write_space; |
| |
| /* Reset to new socket */ |
| xprt->sock = sock; |
| xprt->inet = sk; |
| write_unlock_bh(&sk->sk_callback_lock); |
| |
| return; |
| } |
| |
| /* |
| * Set socket buffer length |
| */ |
| void |
| xprt_sock_setbufsize(struct rpc_xprt *xprt) |
| { |
| struct sock *sk = xprt->inet; |
| |
| if (xprt->stream) |
| return; |
| if (xprt->rcvsize) { |
| sk->sk_userlocks |= SOCK_RCVBUF_LOCK; |
| sk->sk_rcvbuf = xprt->rcvsize * xprt->max_reqs * 2; |
| } |
| if (xprt->sndsize) { |
| sk->sk_userlocks |= SOCK_SNDBUF_LOCK; |
| sk->sk_sndbuf = xprt->sndsize * xprt->max_reqs * 2; |
| sk->sk_write_space(sk); |
| } |
| } |
| |
| /* |
| * Datastream sockets are created here, but xprt_connect will create |
| * and connect stream sockets. |
| */ |
| static struct socket * xprt_create_socket(struct rpc_xprt *xprt, int proto, int resvport) |
| { |
| struct socket *sock; |
| int type, err; |
| |
| dprintk("RPC: xprt_create_socket(%s %d)\n", |
| (proto == IPPROTO_UDP)? "udp" : "tcp", proto); |
| |
| type = (proto == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM; |
| |
| if ((err = sock_create_kern(PF_INET, type, proto, &sock)) < 0) { |
| printk("RPC: can't create socket (%d).\n", -err); |
| return NULL; |
| } |
| |
| /* If the caller has the capability, bind to a reserved port */ |
| if (resvport && xprt_bindresvport(xprt, sock) < 0) { |
| printk("RPC: can't bind to reserved port.\n"); |
| goto failed; |
| } |
| |
| return sock; |
| |
| failed: |
| sock_release(sock); |
| return NULL; |
| } |
| |
| /* |
| * Create an RPC client transport given the protocol and peer address. |
| */ |
| struct rpc_xprt * |
| xprt_create_proto(int proto, struct sockaddr_in *sap, struct rpc_timeout *to) |
| { |
| struct rpc_xprt *xprt; |
| |
| xprt = xprt_setup(proto, sap, to); |
| if (IS_ERR(xprt)) |
| dprintk("RPC: xprt_create_proto failed\n"); |
| else |
| dprintk("RPC: xprt_create_proto created xprt %p\n", xprt); |
| return xprt; |
| } |
| |
| /* |
| * Prepare for transport shutdown. |
| */ |
| static void |
| xprt_shutdown(struct rpc_xprt *xprt) |
| { |
| xprt->shutdown = 1; |
| rpc_wake_up(&xprt->sending); |
| rpc_wake_up(&xprt->resend); |
| rpc_wake_up(&xprt->pending); |
| rpc_wake_up(&xprt->backlog); |
| wake_up(&xprt->cong_wait); |
| del_timer_sync(&xprt->timer); |
| |
| /* synchronously wait for connect worker to finish */ |
| cancel_delayed_work(&xprt->sock_connect); |
| flush_scheduled_work(); |
| } |
| |
| /* |
| * Clear the xprt backlog queue |
| */ |
| static int |
| xprt_clear_backlog(struct rpc_xprt *xprt) { |
| rpc_wake_up_next(&xprt->backlog); |
| wake_up(&xprt->cong_wait); |
| return 1; |
| } |
| |
| /* |
| * Destroy an RPC transport, killing off all requests. |
| */ |
| int |
| xprt_destroy(struct rpc_xprt *xprt) |
| { |
| dprintk("RPC: destroying transport %p\n", xprt); |
| xprt_shutdown(xprt); |
| xprt_disconnect(xprt); |
| xprt_close(xprt); |
| kfree(xprt->slot); |
| kfree(xprt); |
| |
| return 0; |
| } |