![Linus Torvalds](/assets/img/avatar_default.png)
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
1679 lines
40 KiB
C
1679 lines
40 KiB
C
/*
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* linux/net/sunrpc/xprt.c
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*
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* This is a generic RPC call interface supporting congestion avoidance,
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* and asynchronous calls.
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*
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* The interface works like this:
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*
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* - When a process places a call, it allocates a request slot if
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* one is available. Otherwise, it sleeps on the backlog queue
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* (xprt_reserve).
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* - Next, the caller puts together the RPC message, stuffs it into
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* the request struct, and calls xprt_call().
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* - xprt_call transmits the message and installs the caller on the
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* socket's wait list. At the same time, it installs a timer that
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* is run after the packet's timeout has expired.
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* - When a packet arrives, the data_ready handler walks the list of
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* pending requests for that socket. If a matching XID is found, the
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* caller is woken up, and the timer removed.
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* - When no reply arrives within the timeout interval, the timer is
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* fired by the kernel and runs xprt_timer(). It either adjusts the
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* timeout values (minor timeout) or wakes up the caller with a status
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* of -ETIMEDOUT.
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* - When the caller receives a notification from RPC that a reply arrived,
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* it should release the RPC slot, and process the reply.
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* If the call timed out, it may choose to retry the operation by
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* adjusting the initial timeout value, and simply calling rpc_call
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* again.
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*
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* Support for async RPC is done through a set of RPC-specific scheduling
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* primitives that `transparently' work for processes as well as async
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* tasks that rely on callbacks.
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*
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* Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de>
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*
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* TCP callback races fixes (C) 1998 Red Hat Software <alan@redhat.com>
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* TCP send fixes (C) 1998 Red Hat Software <alan@redhat.com>
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* TCP NFS related read + write fixes
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* (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
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*
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* Rewrite of larges part of the code in order to stabilize TCP stuff.
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* Fix behaviour when socket buffer is full.
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* (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
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*/
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#include <linux/types.h>
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#include <linux/slab.h>
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#include <linux/capability.h>
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#include <linux/sched.h>
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#include <linux/errno.h>
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#include <linux/socket.h>
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#include <linux/in.h>
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#include <linux/net.h>
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#include <linux/mm.h>
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#include <linux/udp.h>
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#include <linux/tcp.h>
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#include <linux/sunrpc/clnt.h>
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#include <linux/file.h>
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#include <linux/workqueue.h>
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#include <linux/random.h>
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#include <net/sock.h>
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#include <net/checksum.h>
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#include <net/udp.h>
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#include <net/tcp.h>
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/*
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* Local variables
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*/
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#ifdef RPC_DEBUG
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# undef RPC_DEBUG_DATA
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# define RPCDBG_FACILITY RPCDBG_XPRT
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#endif
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#define XPRT_MAX_BACKOFF (8)
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#define XPRT_IDLE_TIMEOUT (5*60*HZ)
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#define XPRT_MAX_RESVPORT (800)
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/*
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* Local functions
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*/
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static void xprt_request_init(struct rpc_task *, struct rpc_xprt *);
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static inline void do_xprt_reserve(struct rpc_task *);
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static void xprt_disconnect(struct rpc_xprt *);
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static void xprt_connect_status(struct rpc_task *task);
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static struct rpc_xprt * xprt_setup(int proto, struct sockaddr_in *ap,
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struct rpc_timeout *to);
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static struct socket *xprt_create_socket(struct rpc_xprt *, int, int);
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static void xprt_bind_socket(struct rpc_xprt *, struct socket *);
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static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *);
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static int xprt_clear_backlog(struct rpc_xprt *xprt);
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#ifdef RPC_DEBUG_DATA
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/*
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* Print the buffer contents (first 128 bytes only--just enough for
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* diropres return).
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*/
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static void
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xprt_pktdump(char *msg, u32 *packet, unsigned int count)
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{
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u8 *buf = (u8 *) packet;
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int j;
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dprintk("RPC: %s\n", msg);
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for (j = 0; j < count && j < 128; j += 4) {
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if (!(j & 31)) {
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if (j)
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dprintk("\n");
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dprintk("0x%04x ", j);
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}
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dprintk("%02x%02x%02x%02x ",
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buf[j], buf[j+1], buf[j+2], buf[j+3]);
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}
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dprintk("\n");
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}
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#else
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static inline void
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xprt_pktdump(char *msg, u32 *packet, unsigned int count)
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{
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/* NOP */
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}
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#endif
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/*
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* Look up RPC transport given an INET socket
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*/
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static inline struct rpc_xprt *
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xprt_from_sock(struct sock *sk)
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{
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return (struct rpc_xprt *) sk->sk_user_data;
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}
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/*
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* Serialize write access to sockets, in order to prevent different
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* requests from interfering with each other.
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* Also prevents TCP socket connects from colliding with writes.
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*/
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static int
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__xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
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{
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struct rpc_rqst *req = task->tk_rqstp;
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if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate)) {
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if (task == xprt->snd_task)
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return 1;
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if (task == NULL)
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return 0;
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goto out_sleep;
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}
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if (xprt->nocong || __xprt_get_cong(xprt, task)) {
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xprt->snd_task = task;
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if (req) {
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req->rq_bytes_sent = 0;
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req->rq_ntrans++;
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}
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return 1;
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}
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smp_mb__before_clear_bit();
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clear_bit(XPRT_LOCKED, &xprt->sockstate);
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smp_mb__after_clear_bit();
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out_sleep:
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dprintk("RPC: %4d failed to lock socket %p\n", task->tk_pid, xprt);
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task->tk_timeout = 0;
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task->tk_status = -EAGAIN;
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if (req && req->rq_ntrans)
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rpc_sleep_on(&xprt->resend, task, NULL, NULL);
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else
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rpc_sleep_on(&xprt->sending, task, NULL, NULL);
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return 0;
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}
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static inline int
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xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
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{
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int retval;
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spin_lock_bh(&xprt->sock_lock);
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retval = __xprt_lock_write(xprt, task);
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spin_unlock_bh(&xprt->sock_lock);
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return retval;
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}
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static void
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__xprt_lock_write_next(struct rpc_xprt *xprt)
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{
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struct rpc_task *task;
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if (test_and_set_bit(XPRT_LOCKED, &xprt->sockstate))
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return;
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if (!xprt->nocong && RPCXPRT_CONGESTED(xprt))
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goto out_unlock;
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task = rpc_wake_up_next(&xprt->resend);
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if (!task) {
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task = rpc_wake_up_next(&xprt->sending);
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if (!task)
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goto out_unlock;
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}
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if (xprt->nocong || __xprt_get_cong(xprt, task)) {
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struct rpc_rqst *req = task->tk_rqstp;
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xprt->snd_task = task;
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if (req) {
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req->rq_bytes_sent = 0;
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req->rq_ntrans++;
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}
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return;
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}
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out_unlock:
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smp_mb__before_clear_bit();
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clear_bit(XPRT_LOCKED, &xprt->sockstate);
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smp_mb__after_clear_bit();
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}
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/*
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* Releases the socket for use by other requests.
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*/
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static void
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__xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
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{
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if (xprt->snd_task == task) {
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xprt->snd_task = NULL;
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smp_mb__before_clear_bit();
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clear_bit(XPRT_LOCKED, &xprt->sockstate);
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smp_mb__after_clear_bit();
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__xprt_lock_write_next(xprt);
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}
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}
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static inline void
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xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
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{
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spin_lock_bh(&xprt->sock_lock);
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__xprt_release_write(xprt, task);
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spin_unlock_bh(&xprt->sock_lock);
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}
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/*
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* Write data to socket.
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*/
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static inline int
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xprt_sendmsg(struct rpc_xprt *xprt, struct rpc_rqst *req)
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{
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struct socket *sock = xprt->sock;
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struct xdr_buf *xdr = &req->rq_snd_buf;
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struct sockaddr *addr = NULL;
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int addrlen = 0;
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unsigned int skip;
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int result;
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if (!sock)
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return -ENOTCONN;
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xprt_pktdump("packet data:",
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req->rq_svec->iov_base,
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req->rq_svec->iov_len);
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/* For UDP, we need to provide an address */
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if (!xprt->stream) {
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addr = (struct sockaddr *) &xprt->addr;
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addrlen = sizeof(xprt->addr);
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}
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/* Dont repeat bytes */
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skip = req->rq_bytes_sent;
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clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
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result = xdr_sendpages(sock, addr, addrlen, xdr, skip, MSG_DONTWAIT);
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dprintk("RPC: xprt_sendmsg(%d) = %d\n", xdr->len - skip, result);
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if (result >= 0)
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return result;
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switch (result) {
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case -ECONNREFUSED:
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/* When the server has died, an ICMP port unreachable message
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* prompts ECONNREFUSED.
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*/
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case -EAGAIN:
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break;
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case -ECONNRESET:
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case -ENOTCONN:
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case -EPIPE:
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/* connection broken */
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if (xprt->stream)
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result = -ENOTCONN;
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break;
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default:
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printk(KERN_NOTICE "RPC: sendmsg returned error %d\n", -result);
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}
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return result;
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}
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/*
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* Van Jacobson congestion avoidance. Check if the congestion window
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* overflowed. Put the task to sleep if this is the case.
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*/
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static int
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__xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task)
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{
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struct rpc_rqst *req = task->tk_rqstp;
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if (req->rq_cong)
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return 1;
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dprintk("RPC: %4d xprt_cwnd_limited cong = %ld cwnd = %ld\n",
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task->tk_pid, xprt->cong, xprt->cwnd);
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if (RPCXPRT_CONGESTED(xprt))
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return 0;
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req->rq_cong = 1;
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xprt->cong += RPC_CWNDSCALE;
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return 1;
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}
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/*
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* Adjust the congestion window, and wake up the next task
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* that has been sleeping due to congestion
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*/
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static void
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__xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req)
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{
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if (!req->rq_cong)
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return;
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req->rq_cong = 0;
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xprt->cong -= RPC_CWNDSCALE;
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__xprt_lock_write_next(xprt);
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}
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/*
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* Adjust RPC congestion window
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* We use a time-smoothed congestion estimator to avoid heavy oscillation.
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*/
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static void
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xprt_adjust_cwnd(struct rpc_xprt *xprt, int result)
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{
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unsigned long cwnd;
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cwnd = xprt->cwnd;
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if (result >= 0 && cwnd <= xprt->cong) {
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/* The (cwnd >> 1) term makes sure
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* the result gets rounded properly. */
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cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd;
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if (cwnd > RPC_MAXCWND(xprt))
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cwnd = RPC_MAXCWND(xprt);
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__xprt_lock_write_next(xprt);
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} else if (result == -ETIMEDOUT) {
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cwnd >>= 1;
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if (cwnd < RPC_CWNDSCALE)
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cwnd = RPC_CWNDSCALE;
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}
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dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n",
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xprt->cong, xprt->cwnd, cwnd);
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xprt->cwnd = cwnd;
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}
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/*
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* Reset the major timeout value
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*/
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static void xprt_reset_majortimeo(struct rpc_rqst *req)
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{
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struct rpc_timeout *to = &req->rq_xprt->timeout;
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req->rq_majortimeo = req->rq_timeout;
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if (to->to_exponential)
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req->rq_majortimeo <<= to->to_retries;
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else
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req->rq_majortimeo += to->to_increment * to->to_retries;
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if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0)
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req->rq_majortimeo = to->to_maxval;
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req->rq_majortimeo += jiffies;
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}
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|
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/*
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* Adjust timeout values etc for next retransmit
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*/
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int xprt_adjust_timeout(struct rpc_rqst *req)
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{
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struct rpc_xprt *xprt = req->rq_xprt;
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struct rpc_timeout *to = &xprt->timeout;
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int status = 0;
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|
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if (time_before(jiffies, req->rq_majortimeo)) {
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if (to->to_exponential)
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req->rq_timeout <<= 1;
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else
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req->rq_timeout += to->to_increment;
|
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if (to->to_maxval && req->rq_timeout >= to->to_maxval)
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req->rq_timeout = to->to_maxval;
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req->rq_retries++;
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pprintk("RPC: %lu retrans\n", jiffies);
|
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} else {
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req->rq_timeout = to->to_initval;
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req->rq_retries = 0;
|
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xprt_reset_majortimeo(req);
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/* Reset the RTT counters == "slow start" */
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spin_lock_bh(&xprt->sock_lock);
|
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rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval);
|
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spin_unlock_bh(&xprt->sock_lock);
|
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pprintk("RPC: %lu timeout\n", jiffies);
|
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status = -ETIMEDOUT;
|
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}
|
|
|
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if (req->rq_timeout == 0) {
|
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printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n");
|
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req->rq_timeout = 5 * HZ;
|
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}
|
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return status;
|
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}
|
|
|
|
/*
|
|
* Close down a transport socket
|
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*/
|
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static void
|
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xprt_close(struct rpc_xprt *xprt)
|
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{
|
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struct socket *sock = xprt->sock;
|
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struct sock *sk = xprt->inet;
|
|
|
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if (!sk)
|
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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);
|
|
}
|
|
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;
|
|
}
|
|
|
|
/* if soft mounted, just cause this RPC to fail */
|
|
if (RPC_IS_SOFT(task))
|
|
task->tk_status = -EIO;
|
|
|
|
switch (task->tk_status) {
|
|
case -ECONNREFUSED:
|
|
case -ECONNRESET:
|
|
case -ENOTCONN:
|
|
return;
|
|
case -ETIMEDOUT:
|
|
dprintk("RPC: %4d xprt_connect_status: timed out\n",
|
|
task->tk_pid);
|
|
break;
|
|
default:
|
|
printk(KERN_ERR "RPC: error %d connecting to server %s\n",
|
|
-task->tk_status, task->tk_client->cl_server);
|
|
}
|
|
xprt_release_write(xprt, task);
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
static size_t
|
|
skb_read_bits(skb_reader_t *desc, void *to, size_t len)
|
|
{
|
|
if (len > desc->count)
|
|
len = desc->count;
|
|
if (skb_copy_bits(desc->skb, desc->offset, to, len))
|
|
return 0;
|
|
desc->count -= len;
|
|
desc->offset += len;
|
|
return len;
|
|
}
|
|
|
|
static size_t
|
|
skb_read_and_csum_bits(skb_reader_t *desc, void *to, size_t len)
|
|
{
|
|
unsigned int csum2, pos;
|
|
|
|
if (len > desc->count)
|
|
len = desc->count;
|
|
pos = desc->offset;
|
|
csum2 = skb_copy_and_csum_bits(desc->skb, pos, to, len, 0);
|
|
desc->csum = csum_block_add(desc->csum, csum2, pos);
|
|
desc->count -= len;
|
|
desc->offset += len;
|
|
return len;
|
|
}
|
|
|
|
/*
|
|
* We have set things up such that we perform the checksum of the UDP
|
|
* packet in parallel with the copies into the RPC client iovec. -DaveM
|
|
*/
|
|
int
|
|
csum_partial_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb)
|
|
{
|
|
skb_reader_t desc;
|
|
|
|
desc.skb = skb;
|
|
desc.offset = sizeof(struct udphdr);
|
|
desc.count = skb->len - desc.offset;
|
|
|
|
if (skb->ip_summed == CHECKSUM_UNNECESSARY)
|
|
goto no_checksum;
|
|
|
|
desc.csum = csum_partial(skb->data, desc.offset, skb->csum);
|
|
xdr_partial_copy_from_skb(xdr, 0, &desc, skb_read_and_csum_bits);
|
|
if (desc.offset != skb->len) {
|
|
unsigned int csum2;
|
|
csum2 = skb_checksum(skb, desc.offset, skb->len - desc.offset, 0);
|
|
desc.csum = csum_block_add(desc.csum, csum2, desc.offset);
|
|
}
|
|
if (desc.count)
|
|
return -1;
|
|
if ((unsigned short)csum_fold(desc.csum))
|
|
return -1;
|
|
return 0;
|
|
no_checksum:
|
|
xdr_partial_copy_from_skb(xdr, 0, &desc, skb_read_bits);
|
|
if (desc.count)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* 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))
|
|
return 0;
|
|
desc->offset += len;
|
|
desc->count -= len;
|
|
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)
|
|
{
|
|
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;
|
|
|
|
/* 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;
|
|
xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied,
|
|
&my_desc, tcp_copy_data);
|
|
desc->count -= len;
|
|
desc->offset += len;
|
|
} else
|
|
xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied,
|
|
desc, tcp_copy_data);
|
|
xprt->tcp_copied += len;
|
|
xprt->tcp_offset += len;
|
|
|
|
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;
|
|
}
|
|
|
|
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;
|
|
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:
|
|
if (xprt_test_and_clear_connected(xprt))
|
|
rpc_wake_up_status(&xprt->pending, -ENOTCONN);
|
|
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);
|
|
}
|
|
} 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);
|
|
if (task->tk_rqstp)
|
|
del_timer_sync(&xprt->timer);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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, 5, 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 = 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);
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
}
|