diff options
Diffstat (limited to 'net/sunrpc/xprt.c')
| -rw-r--r-- | net/sunrpc/xprt.c | 1678 |
1 files changed, 1678 insertions, 0 deletions
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c new file mode 100644 index 000000000000..c74a6bb94074 --- /dev/null +++ b/net/sunrpc/xprt.c @@ -0,0 +1,1678 @@ +/* + * 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; + if (task == NULL) + return 0; + 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); + } + 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; +} |