linux/net/sunrpc/xprtsock.c
Chuck Lever b22602a673 SUNRPC: Ensure all transports set rq_xtime consistently
The RPC client uses the rq_xtime field in each RPC request to determine the
round-trip time of the request.  Currently, the rq_xtime field is
initialized by each transport just before it starts enqueing a request to
be sent.  However, transports do not handle initializing this value
consistently; sometimes they don't initialize it at all.

To make the measurement of request round-trip time consistent for all
RPC client transport capabilities, pull rq_xtime initialization into the
RPC client's generic transport logic.  Now all transports will get a
standardized RTT measure automatically, from:

  xprt_transmit()

to

  xprt_complete_rqst()

This makes round-trip time calculation more accurate for the TCP transport.
The socket ->sendmsg() method can return "-EAGAIN" if the socket's output
buffer is full, so the TCP transport's ->send_request() method may call
the ->sendmsg() method repeatedly until it gets all of the request's bytes
queued in the socket's buffer.

Currently, the TCP transport sets the rq_xtime field every time through
that loop so the final value is the timestamp just before the *last* call
to the underlying socket's ->sendmsg() method.  After this patch, the
rq_xtime field contains a timestamp that reflects the time just before the
*first* call to ->sendmsg().

This is consequential under heavy workloads because large requests often
take multiple ->sendmsg() calls to get all the bytes of a request queued.
The TCP transport causes the request to sleep until the remote end of the
socket has received enough bytes to clear space in the socket's local
output buffer.  This delay can be quite significant.

The method introduced by this patch is a more accurate measure of RTT
for stream transports, since the server can cause enough back pressure
to delay (ie increase the latency of) requests from the client.

Additionally, this patch corrects the behavior of the RDMA transport, which
entirely neglected to initialize the rq_xtime field.  RPC performance
metrics for RDMA transports now display correct RPC request round trip
times.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Tom Talpey <thomas.talpey@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:15 -04:00

2091 lines
54 KiB
C

/*
* linux/net/sunrpc/xprtsock.c
*
* Client-side transport implementation for sockets.
*
* 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>
*
* IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
*
* IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
* <gilles.quillard@bull.net>
*/
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/capability.h>
#include <linux/pagemap.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/sunrpc/sched.h>
#include <linux/sunrpc/xprtsock.h>
#include <linux/file.h>
#include <net/sock.h>
#include <net/checksum.h>
#include <net/udp.h>
#include <net/tcp.h>
/*
* xprtsock tunables
*/
unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
unsigned int xprt_tcp_slot_table_entries = RPC_DEF_SLOT_TABLE;
unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
/*
* We can register our own files under /proc/sys/sunrpc by
* calling register_sysctl_table() again. The files in that
* directory become the union of all files registered there.
*
* We simply need to make sure that we don't collide with
* someone else's file names!
*/
#ifdef RPC_DEBUG
static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
static struct ctl_table_header *sunrpc_table_header;
/*
* FIXME: changing the UDP slot table size should also resize the UDP
* socket buffers for existing UDP transports
*/
static ctl_table xs_tunables_table[] = {
{
.ctl_name = CTL_SLOTTABLE_UDP,
.procname = "udp_slot_table_entries",
.data = &xprt_udp_slot_table_entries,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &min_slot_table_size,
.extra2 = &max_slot_table_size
},
{
.ctl_name = CTL_SLOTTABLE_TCP,
.procname = "tcp_slot_table_entries",
.data = &xprt_tcp_slot_table_entries,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &min_slot_table_size,
.extra2 = &max_slot_table_size
},
{
.ctl_name = CTL_MIN_RESVPORT,
.procname = "min_resvport",
.data = &xprt_min_resvport,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &xprt_min_resvport_limit,
.extra2 = &xprt_max_resvport_limit
},
{
.ctl_name = CTL_MAX_RESVPORT,
.procname = "max_resvport",
.data = &xprt_max_resvport,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
.extra1 = &xprt_min_resvport_limit,
.extra2 = &xprt_max_resvport_limit
},
{
.ctl_name = 0,
},
};
static ctl_table sunrpc_table[] = {
{
.ctl_name = CTL_SUNRPC,
.procname = "sunrpc",
.mode = 0555,
.child = xs_tunables_table
},
{
.ctl_name = 0,
},
};
#endif
/*
* Time out for an RPC UDP socket connect. UDP socket connects are
* synchronous, but we set a timeout anyway in case of resource
* exhaustion on the local host.
*/
#define XS_UDP_CONN_TO (5U * HZ)
/*
* Wait duration for an RPC TCP connection to be established. Solaris
* NFS over TCP uses 60 seconds, for example, which is in line with how
* long a server takes to reboot.
*/
#define XS_TCP_CONN_TO (60U * HZ)
/*
* Wait duration for a reply from the RPC portmapper.
*/
#define XS_BIND_TO (60U * HZ)
/*
* Delay if a UDP socket connect error occurs. This is most likely some
* kind of resource problem on the local host.
*/
#define XS_UDP_REEST_TO (2U * HZ)
/*
* The reestablish timeout allows clients to delay for a bit before attempting
* to reconnect to a server that just dropped our connection.
*
* We implement an exponential backoff when trying to reestablish a TCP
* transport connection with the server. Some servers like to drop a TCP
* connection when they are overworked, so we start with a short timeout and
* increase over time if the server is down or not responding.
*/
#define XS_TCP_INIT_REEST_TO (3U * HZ)
#define XS_TCP_MAX_REEST_TO (5U * 60 * HZ)
/*
* TCP idle timeout; client drops the transport socket if it is idle
* for this long. Note that we also timeout UDP sockets to prevent
* holding port numbers when there is no RPC traffic.
*/
#define XS_IDLE_DISC_TO (5U * 60 * HZ)
#ifdef RPC_DEBUG
# undef RPC_DEBUG_DATA
# define RPCDBG_FACILITY RPCDBG_TRANS
#endif
#ifdef RPC_DEBUG_DATA
static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
{
u8 *buf = (u8 *) packet;
int j;
dprintk("RPC: %s\n", msg);
for (j = 0; j < count && j < 128; j += 4) {
if (!(j & 31)) {
if (j)
dprintk("\n");
dprintk("0x%04x ", j);
}
dprintk("%02x%02x%02x%02x ",
buf[j], buf[j+1], buf[j+2], buf[j+3]);
}
dprintk("\n");
}
#else
static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
{
/* NOP */
}
#endif
struct sock_xprt {
struct rpc_xprt xprt;
/*
* Network layer
*/
struct socket * sock;
struct sock * inet;
/*
* State of TCP reply receive
*/
__be32 tcp_fraghdr,
tcp_xid;
u32 tcp_offset,
tcp_reclen;
unsigned long tcp_copied,
tcp_flags;
/*
* Connection of transports
*/
struct delayed_work connect_worker;
struct sockaddr_storage addr;
unsigned short port;
/*
* UDP socket buffer size parameters
*/
size_t rcvsize,
sndsize;
/*
* Saved socket callback addresses
*/
void (*old_data_ready)(struct sock *, int);
void (*old_state_change)(struct sock *);
void (*old_write_space)(struct sock *);
};
/*
* TCP receive state flags
*/
#define TCP_RCV_LAST_FRAG (1UL << 0)
#define TCP_RCV_COPY_FRAGHDR (1UL << 1)
#define TCP_RCV_COPY_XID (1UL << 2)
#define TCP_RCV_COPY_DATA (1UL << 3)
static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
{
return (struct sockaddr *) &xprt->addr;
}
static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
{
return (struct sockaddr_in *) &xprt->addr;
}
static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
{
return (struct sockaddr_in6 *) &xprt->addr;
}
static void xs_format_ipv4_peer_addresses(struct rpc_xprt *xprt,
const char *protocol,
const char *netid)
{
struct sockaddr_in *addr = xs_addr_in(xprt);
char *buf;
buf = kzalloc(20, GFP_KERNEL);
if (buf) {
snprintf(buf, 20, NIPQUAD_FMT,
NIPQUAD(addr->sin_addr.s_addr));
}
xprt->address_strings[RPC_DISPLAY_ADDR] = buf;
buf = kzalloc(8, GFP_KERNEL);
if (buf) {
snprintf(buf, 8, "%u",
ntohs(addr->sin_port));
}
xprt->address_strings[RPC_DISPLAY_PORT] = buf;
xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
buf = kzalloc(48, GFP_KERNEL);
if (buf) {
snprintf(buf, 48, "addr="NIPQUAD_FMT" port=%u proto=%s",
NIPQUAD(addr->sin_addr.s_addr),
ntohs(addr->sin_port),
protocol);
}
xprt->address_strings[RPC_DISPLAY_ALL] = buf;
buf = kzalloc(10, GFP_KERNEL);
if (buf) {
snprintf(buf, 10, "%02x%02x%02x%02x",
NIPQUAD(addr->sin_addr.s_addr));
}
xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = buf;
buf = kzalloc(8, GFP_KERNEL);
if (buf) {
snprintf(buf, 8, "%4hx",
ntohs(addr->sin_port));
}
xprt->address_strings[RPC_DISPLAY_HEX_PORT] = buf;
buf = kzalloc(30, GFP_KERNEL);
if (buf) {
snprintf(buf, 30, NIPQUAD_FMT".%u.%u",
NIPQUAD(addr->sin_addr.s_addr),
ntohs(addr->sin_port) >> 8,
ntohs(addr->sin_port) & 0xff);
}
xprt->address_strings[RPC_DISPLAY_UNIVERSAL_ADDR] = buf;
xprt->address_strings[RPC_DISPLAY_NETID] = netid;
}
static void xs_format_ipv6_peer_addresses(struct rpc_xprt *xprt,
const char *protocol,
const char *netid)
{
struct sockaddr_in6 *addr = xs_addr_in6(xprt);
char *buf;
buf = kzalloc(40, GFP_KERNEL);
if (buf) {
snprintf(buf, 40, NIP6_FMT,
NIP6(addr->sin6_addr));
}
xprt->address_strings[RPC_DISPLAY_ADDR] = buf;
buf = kzalloc(8, GFP_KERNEL);
if (buf) {
snprintf(buf, 8, "%u",
ntohs(addr->sin6_port));
}
xprt->address_strings[RPC_DISPLAY_PORT] = buf;
xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
buf = kzalloc(64, GFP_KERNEL);
if (buf) {
snprintf(buf, 64, "addr="NIP6_FMT" port=%u proto=%s",
NIP6(addr->sin6_addr),
ntohs(addr->sin6_port),
protocol);
}
xprt->address_strings[RPC_DISPLAY_ALL] = buf;
buf = kzalloc(36, GFP_KERNEL);
if (buf) {
snprintf(buf, 36, NIP6_SEQFMT,
NIP6(addr->sin6_addr));
}
xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = buf;
buf = kzalloc(8, GFP_KERNEL);
if (buf) {
snprintf(buf, 8, "%4hx",
ntohs(addr->sin6_port));
}
xprt->address_strings[RPC_DISPLAY_HEX_PORT] = buf;
buf = kzalloc(50, GFP_KERNEL);
if (buf) {
snprintf(buf, 50, NIP6_FMT".%u.%u",
NIP6(addr->sin6_addr),
ntohs(addr->sin6_port) >> 8,
ntohs(addr->sin6_port) & 0xff);
}
xprt->address_strings[RPC_DISPLAY_UNIVERSAL_ADDR] = buf;
xprt->address_strings[RPC_DISPLAY_NETID] = netid;
}
static void xs_free_peer_addresses(struct rpc_xprt *xprt)
{
unsigned int i;
for (i = 0; i < RPC_DISPLAY_MAX; i++)
switch (i) {
case RPC_DISPLAY_PROTO:
case RPC_DISPLAY_NETID:
continue;
default:
kfree(xprt->address_strings[i]);
}
}
#define XS_SENDMSG_FLAGS (MSG_DONTWAIT | MSG_NOSIGNAL)
static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
{
struct msghdr msg = {
.msg_name = addr,
.msg_namelen = addrlen,
.msg_flags = XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
};
struct kvec iov = {
.iov_base = vec->iov_base + base,
.iov_len = vec->iov_len - base,
};
if (iov.iov_len != 0)
return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
return kernel_sendmsg(sock, &msg, NULL, 0, 0);
}
static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more)
{
struct page **ppage;
unsigned int remainder;
int err, sent = 0;
remainder = xdr->page_len - base;
base += xdr->page_base;
ppage = xdr->pages + (base >> PAGE_SHIFT);
base &= ~PAGE_MASK;
for(;;) {
unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
int flags = XS_SENDMSG_FLAGS;
remainder -= len;
if (remainder != 0 || more)
flags |= MSG_MORE;
err = sock->ops->sendpage(sock, *ppage, base, len, flags);
if (remainder == 0 || err != len)
break;
sent += err;
ppage++;
base = 0;
}
if (sent == 0)
return err;
if (err > 0)
sent += err;
return sent;
}
/**
* xs_sendpages - write pages directly to a socket
* @sock: socket to send on
* @addr: UDP only -- address of destination
* @addrlen: UDP only -- length of destination address
* @xdr: buffer containing this request
* @base: starting position in the buffer
*
*/
static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base)
{
unsigned int remainder = xdr->len - base;
int err, sent = 0;
if (unlikely(!sock))
return -ENOTCONN;
clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
if (base != 0) {
addr = NULL;
addrlen = 0;
}
if (base < xdr->head[0].iov_len || addr != NULL) {
unsigned int len = xdr->head[0].iov_len - base;
remainder -= len;
err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
if (remainder == 0 || err != len)
goto out;
sent += err;
base = 0;
} else
base -= xdr->head[0].iov_len;
if (base < xdr->page_len) {
unsigned int len = xdr->page_len - base;
remainder -= len;
err = xs_send_pagedata(sock, xdr, base, remainder != 0);
if (remainder == 0 || err != len)
goto out;
sent += err;
base = 0;
} else
base -= xdr->page_len;
if (base >= xdr->tail[0].iov_len)
return sent;
err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
out:
if (sent == 0)
return err;
if (err > 0)
sent += err;
return sent;
}
static void xs_nospace_callback(struct rpc_task *task)
{
struct sock_xprt *transport = container_of(task->tk_rqstp->rq_xprt, struct sock_xprt, xprt);
transport->inet->sk_write_pending--;
clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
}
/**
* xs_nospace - place task on wait queue if transmit was incomplete
* @task: task to put to sleep
*
*/
static void xs_nospace(struct rpc_task *task)
{
struct rpc_rqst *req = task->tk_rqstp;
struct rpc_xprt *xprt = req->rq_xprt;
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
task->tk_pid, req->rq_slen - req->rq_bytes_sent,
req->rq_slen);
/* Protect against races with write_space */
spin_lock_bh(&xprt->transport_lock);
/* Don't race with disconnect */
if (xprt_connected(xprt)) {
if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) {
/*
* Notify TCP that we're limited by the application
* window size
*/
set_bit(SOCK_NOSPACE, &transport->sock->flags);
transport->inet->sk_write_pending++;
/* ...and wait for more buffer space */
xprt_wait_for_buffer_space(task, xs_nospace_callback);
}
} else {
clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
task->tk_status = -ENOTCONN;
}
spin_unlock_bh(&xprt->transport_lock);
}
/**
* xs_udp_send_request - write an RPC request to a UDP socket
* @task: address of RPC task that manages the state of an RPC request
*
* Return values:
* 0: The request has been sent
* EAGAIN: The socket was blocked, please call again later to
* complete the request
* ENOTCONN: Caller needs to invoke connect logic then call again
* other: Some other error occured, the request was not sent
*/
static int xs_udp_send_request(struct rpc_task *task)
{
struct rpc_rqst *req = task->tk_rqstp;
struct rpc_xprt *xprt = req->rq_xprt;
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
struct xdr_buf *xdr = &req->rq_snd_buf;
int status;
xs_pktdump("packet data:",
req->rq_svec->iov_base,
req->rq_svec->iov_len);
status = xs_sendpages(transport->sock,
xs_addr(xprt),
xprt->addrlen, xdr,
req->rq_bytes_sent);
dprintk("RPC: xs_udp_send_request(%u) = %d\n",
xdr->len - req->rq_bytes_sent, status);
if (status >= 0) {
task->tk_bytes_sent += status;
if (status >= req->rq_slen)
return 0;
/* Still some bytes left; set up for a retry later. */
status = -EAGAIN;
}
switch (status) {
case -EAGAIN:
xs_nospace(task);
break;
case -ENETUNREACH:
case -EPIPE:
case -ECONNREFUSED:
/* When the server has died, an ICMP port unreachable message
* prompts ECONNREFUSED. */
clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
break;
default:
clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
dprintk("RPC: sendmsg returned unrecognized error %d\n",
-status);
}
return status;
}
/**
* xs_tcp_shutdown - gracefully shut down a TCP socket
* @xprt: transport
*
* Initiates a graceful shutdown of the TCP socket by calling the
* equivalent of shutdown(SHUT_WR);
*/
static void xs_tcp_shutdown(struct rpc_xprt *xprt)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
struct socket *sock = transport->sock;
if (sock != NULL)
kernel_sock_shutdown(sock, SHUT_WR);
}
static inline void xs_encode_tcp_record_marker(struct xdr_buf *buf)
{
u32 reclen = buf->len - sizeof(rpc_fraghdr);
rpc_fraghdr *base = buf->head[0].iov_base;
*base = htonl(RPC_LAST_STREAM_FRAGMENT | reclen);
}
/**
* xs_tcp_send_request - write an RPC request to a TCP socket
* @task: address of RPC task that manages the state of an RPC request
*
* Return values:
* 0: The request has been sent
* EAGAIN: The socket was blocked, please call again later to
* complete the request
* ENOTCONN: Caller needs to invoke connect logic then call again
* other: Some other error occured, the request was not sent
*
* XXX: In the case of soft timeouts, should we eventually give up
* if sendmsg is not able to make progress?
*/
static int xs_tcp_send_request(struct rpc_task *task)
{
struct rpc_rqst *req = task->tk_rqstp;
struct rpc_xprt *xprt = req->rq_xprt;
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
struct xdr_buf *xdr = &req->rq_snd_buf;
int status;
xs_encode_tcp_record_marker(&req->rq_snd_buf);
xs_pktdump("packet data:",
req->rq_svec->iov_base,
req->rq_svec->iov_len);
/* Continue transmitting the packet/record. We must be careful
* to cope with writespace callbacks arriving _after_ we have
* called sendmsg(). */
while (1) {
status = xs_sendpages(transport->sock,
NULL, 0, xdr, req->rq_bytes_sent);
dprintk("RPC: xs_tcp_send_request(%u) = %d\n",
xdr->len - req->rq_bytes_sent, status);
if (unlikely(status < 0))
break;
/* If we've sent the entire packet, immediately
* reset the count of bytes sent. */
req->rq_bytes_sent += status;
task->tk_bytes_sent += status;
if (likely(req->rq_bytes_sent >= req->rq_slen)) {
req->rq_bytes_sent = 0;
return 0;
}
if (status != 0)
continue;
status = -EAGAIN;
break;
}
switch (status) {
case -EAGAIN:
xs_nospace(task);
break;
case -ECONNREFUSED:
case -ECONNRESET:
case -ENOTCONN:
case -EPIPE:
status = -ENOTCONN;
clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
break;
default:
dprintk("RPC: sendmsg returned unrecognized error %d\n",
-status);
clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
xs_tcp_shutdown(xprt);
}
return status;
}
/**
* xs_tcp_release_xprt - clean up after a tcp transmission
* @xprt: transport
* @task: rpc task
*
* This cleans up if an error causes us to abort the transmission of a request.
* In this case, the socket may need to be reset in order to avoid confusing
* the server.
*/
static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
{
struct rpc_rqst *req;
if (task != xprt->snd_task)
return;
if (task == NULL)
goto out_release;
req = task->tk_rqstp;
if (req->rq_bytes_sent == 0)
goto out_release;
if (req->rq_bytes_sent == req->rq_snd_buf.len)
goto out_release;
set_bit(XPRT_CLOSE_WAIT, &task->tk_xprt->state);
out_release:
xprt_release_xprt(xprt, task);
}
/**
* xs_close - close a socket
* @xprt: transport
*
* This is used when all requests are complete; ie, no DRC state remains
* on the server we want to save.
*/
static void xs_close(struct rpc_xprt *xprt)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
struct socket *sock = transport->sock;
struct sock *sk = transport->inet;
if (!sk)
goto clear_close_wait;
dprintk("RPC: xs_close xprt %p\n", xprt);
write_lock_bh(&sk->sk_callback_lock);
transport->inet = NULL;
transport->sock = NULL;
sk->sk_user_data = NULL;
sk->sk_data_ready = transport->old_data_ready;
sk->sk_state_change = transport->old_state_change;
sk->sk_write_space = transport->old_write_space;
write_unlock_bh(&sk->sk_callback_lock);
sk->sk_no_check = 0;
sock_release(sock);
clear_close_wait:
smp_mb__before_clear_bit();
clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
clear_bit(XPRT_CLOSING, &xprt->state);
smp_mb__after_clear_bit();
xprt_disconnect_done(xprt);
}
/**
* xs_destroy - prepare to shutdown a transport
* @xprt: doomed transport
*
*/
static void xs_destroy(struct rpc_xprt *xprt)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
dprintk("RPC: xs_destroy xprt %p\n", xprt);
cancel_rearming_delayed_work(&transport->connect_worker);
xs_close(xprt);
xs_free_peer_addresses(xprt);
kfree(xprt->slot);
kfree(xprt);
module_put(THIS_MODULE);
}
static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
{
return (struct rpc_xprt *) sk->sk_user_data;
}
/**
* xs_udp_data_ready - "data ready" callback for UDP sockets
* @sk: socket with data to read
* @len: how much data to read
*
*/
static void xs_udp_data_ready(struct sock *sk, int len)
{
struct rpc_task *task;
struct rpc_xprt *xprt;
struct rpc_rqst *rovr;
struct sk_buff *skb;
int err, repsize, copied;
u32 _xid;
__be32 *xp;
read_lock(&sk->sk_callback_lock);
dprintk("RPC: xs_udp_data_ready...\n");
if (!(xprt = xprt_from_sock(sk)))
goto out;
if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
goto out;
if (xprt->shutdown)
goto dropit;
repsize = skb->len - sizeof(struct udphdr);
if (repsize < 4) {
dprintk("RPC: impossible RPC reply size %d!\n", repsize);
goto dropit;
}
/* Copy the XID from the skb... */
xp = skb_header_pointer(skb, sizeof(struct udphdr),
sizeof(_xid), &_xid);
if (xp == NULL)
goto dropit;
/* Look up and lock the request corresponding to the given XID */
spin_lock(&xprt->transport_lock);
rovr = xprt_lookup_rqst(xprt, *xp);
if (!rovr)
goto out_unlock;
task = rovr->rq_task;
if ((copied = rovr->rq_private_buf.buflen) > repsize)
copied = repsize;
/* Suck it into the iovec, verify checksum if not done by hw. */
if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
UDPX_INC_STATS_BH(sk, UDP_MIB_INERRORS);
goto out_unlock;
}
UDPX_INC_STATS_BH(sk, UDP_MIB_INDATAGRAMS);
/* Something worked... */
dst_confirm(skb->dst);
xprt_adjust_cwnd(task, copied);
xprt_update_rtt(task);
xprt_complete_rqst(task, copied);
out_unlock:
spin_unlock(&xprt->transport_lock);
dropit:
skb_free_datagram(sk, skb);
out:
read_unlock(&sk->sk_callback_lock);
}
static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
size_t len, used;
char *p;
p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset;
len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset;
used = xdr_skb_read_bits(desc, p, len);
transport->tcp_offset += used;
if (used != len)
return;
transport->tcp_reclen = ntohl(transport->tcp_fraghdr);
if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
transport->tcp_flags |= TCP_RCV_LAST_FRAG;
else
transport->tcp_flags &= ~TCP_RCV_LAST_FRAG;
transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR;
transport->tcp_offset = 0;
/* Sanity check of the record length */
if (unlikely(transport->tcp_reclen < 4)) {
dprintk("RPC: invalid TCP record fragment length\n");
xprt_force_disconnect(xprt);
return;
}
dprintk("RPC: reading TCP record fragment of length %d\n",
transport->tcp_reclen);
}
static void xs_tcp_check_fraghdr(struct sock_xprt *transport)
{
if (transport->tcp_offset == transport->tcp_reclen) {
transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR;
transport->tcp_offset = 0;
if (transport->tcp_flags & TCP_RCV_LAST_FRAG) {
transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
transport->tcp_flags |= TCP_RCV_COPY_XID;
transport->tcp_copied = 0;
}
}
}
static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc)
{
size_t len, used;
char *p;
len = sizeof(transport->tcp_xid) - transport->tcp_offset;
dprintk("RPC: reading XID (%Zu bytes)\n", len);
p = ((char *) &transport->tcp_xid) + transport->tcp_offset;
used = xdr_skb_read_bits(desc, p, len);
transport->tcp_offset += used;
if (used != len)
return;
transport->tcp_flags &= ~TCP_RCV_COPY_XID;
transport->tcp_flags |= TCP_RCV_COPY_DATA;
transport->tcp_copied = 4;
dprintk("RPC: reading reply for XID %08x\n",
ntohl(transport->tcp_xid));
xs_tcp_check_fraghdr(transport);
}
static inline void xs_tcp_read_request(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
struct rpc_rqst *req;
struct xdr_buf *rcvbuf;
size_t len;
ssize_t r;
/* Find and lock the request corresponding to this xid */
spin_lock(&xprt->transport_lock);
req = xprt_lookup_rqst(xprt, transport->tcp_xid);
if (!req) {
transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
dprintk("RPC: XID %08x request not found!\n",
ntohl(transport->tcp_xid));
spin_unlock(&xprt->transport_lock);
return;
}
rcvbuf = &req->rq_private_buf;
len = desc->count;
if (len > transport->tcp_reclen - transport->tcp_offset) {
struct xdr_skb_reader my_desc;
len = transport->tcp_reclen - transport->tcp_offset;
memcpy(&my_desc, desc, sizeof(my_desc));
my_desc.count = len;
r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
&my_desc, xdr_skb_read_bits);
desc->count -= r;
desc->offset += r;
} else
r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
desc, xdr_skb_read_bits);
if (r > 0) {
transport->tcp_copied += r;
transport->tcp_offset += r;
}
if (r != len) {
/* Error when copying to the receive buffer,
* usually because we weren't able to allocate
* additional buffer pages. All we can do now
* is turn off TCP_RCV_COPY_DATA, so the request
* will not receive any additional updates,
* and time out.
* Any remaining data from this record will
* be discarded.
*/
transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
dprintk("RPC: XID %08x truncated request\n",
ntohl(transport->tcp_xid));
dprintk("RPC: xprt = %p, tcp_copied = %lu, "
"tcp_offset = %u, tcp_reclen = %u\n",
xprt, transport->tcp_copied,
transport->tcp_offset, transport->tcp_reclen);
goto out;
}
dprintk("RPC: XID %08x read %Zd bytes\n",
ntohl(transport->tcp_xid), r);
dprintk("RPC: xprt = %p, tcp_copied = %lu, tcp_offset = %u, "
"tcp_reclen = %u\n", xprt, transport->tcp_copied,
transport->tcp_offset, transport->tcp_reclen);
if (transport->tcp_copied == req->rq_private_buf.buflen)
transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
else if (transport->tcp_offset == transport->tcp_reclen) {
if (transport->tcp_flags & TCP_RCV_LAST_FRAG)
transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
}
out:
if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
xprt_complete_rqst(req->rq_task, transport->tcp_copied);
spin_unlock(&xprt->transport_lock);
xs_tcp_check_fraghdr(transport);
}
static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc)
{
size_t len;
len = transport->tcp_reclen - transport->tcp_offset;
if (len > desc->count)
len = desc->count;
desc->count -= len;
desc->offset += len;
transport->tcp_offset += len;
dprintk("RPC: discarded %Zu bytes\n", len);
xs_tcp_check_fraghdr(transport);
}
static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
{
struct rpc_xprt *xprt = rd_desc->arg.data;
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
struct xdr_skb_reader desc = {
.skb = skb,
.offset = offset,
.count = len,
};
dprintk("RPC: xs_tcp_data_recv started\n");
do {
/* Read in a new fragment marker if necessary */
/* Can we ever really expect to get completely empty fragments? */
if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) {
xs_tcp_read_fraghdr(xprt, &desc);
continue;
}
/* Read in the xid if necessary */
if (transport->tcp_flags & TCP_RCV_COPY_XID) {
xs_tcp_read_xid(transport, &desc);
continue;
}
/* Read in the request data */
if (transport->tcp_flags & TCP_RCV_COPY_DATA) {
xs_tcp_read_request(xprt, &desc);
continue;
}
/* Skip over any trailing bytes on short reads */
xs_tcp_read_discard(transport, &desc);
} while (desc.count);
dprintk("RPC: xs_tcp_data_recv done\n");
return len - desc.count;
}
/**
* xs_tcp_data_ready - "data ready" callback for TCP sockets
* @sk: socket with data to read
* @bytes: how much data to read
*
*/
static void xs_tcp_data_ready(struct sock *sk, int bytes)
{
struct rpc_xprt *xprt;
read_descriptor_t rd_desc;
int read;
dprintk("RPC: xs_tcp_data_ready...\n");
read_lock(&sk->sk_callback_lock);
if (!(xprt = xprt_from_sock(sk)))
goto out;
if (xprt->shutdown)
goto out;
/* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
rd_desc.arg.data = xprt;
do {
rd_desc.count = 65536;
read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
} while (read > 0);
out:
read_unlock(&sk->sk_callback_lock);
}
/**
* xs_tcp_state_change - callback to handle TCP socket state changes
* @sk: socket whose state has changed
*
*/
static void xs_tcp_state_change(struct sock *sk)
{
struct rpc_xprt *xprt;
read_lock(&sk->sk_callback_lock);
if (!(xprt = xprt_from_sock(sk)))
goto out;
dprintk("RPC: xs_tcp_state_change client %p...\n", xprt);
dprintk("RPC: state %x conn %d dead %d zapped %d\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->transport_lock);
if (!xprt_test_and_set_connected(xprt)) {
struct sock_xprt *transport = container_of(xprt,
struct sock_xprt, xprt);
/* Reset TCP record info */
transport->tcp_offset = 0;
transport->tcp_reclen = 0;
transport->tcp_copied = 0;
transport->tcp_flags =
TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
xprt_wake_pending_tasks(xprt, 0);
}
spin_unlock_bh(&xprt->transport_lock);
break;
case TCP_FIN_WAIT1:
/* The client initiated a shutdown of the socket */
xprt->connect_cookie++;
xprt->reestablish_timeout = 0;
set_bit(XPRT_CLOSING, &xprt->state);
smp_mb__before_clear_bit();
clear_bit(XPRT_CONNECTED, &xprt->state);
clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
smp_mb__after_clear_bit();
break;
case TCP_CLOSE_WAIT:
/* The server initiated a shutdown of the socket */
set_bit(XPRT_CLOSING, &xprt->state);
xprt_force_disconnect(xprt);
case TCP_SYN_SENT:
xprt->connect_cookie++;
case TCP_CLOSING:
/*
* If the server closed down the connection, make sure that
* we back off before reconnecting
*/
if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
break;
case TCP_LAST_ACK:
smp_mb__before_clear_bit();
clear_bit(XPRT_CONNECTED, &xprt->state);
smp_mb__after_clear_bit();
break;
case TCP_CLOSE:
smp_mb__before_clear_bit();
clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
clear_bit(XPRT_CLOSING, &xprt->state);
smp_mb__after_clear_bit();
/* Mark transport as closed and wake up all pending tasks */
xprt_disconnect_done(xprt);
}
out:
read_unlock(&sk->sk_callback_lock);
}
/**
* xs_udp_write_space - callback invoked when socket buffer space
* becomes available
* @sk: socket whose state has changed
*
* Called when more output buffer space is available for this socket.
* We try not to wake our writers until they can make "significant"
* progress, otherwise we'll waste resources thrashing kernel_sendmsg
* with a bunch of small requests.
*/
static void xs_udp_write_space(struct sock *sk)
{
read_lock(&sk->sk_callback_lock);
/* from net/core/sock.c:sock_def_write_space */
if (sock_writeable(sk)) {
struct socket *sock;
struct rpc_xprt *xprt;
if (unlikely(!(sock = sk->sk_socket)))
goto out;
clear_bit(SOCK_NOSPACE, &sock->flags);
if (unlikely(!(xprt = xprt_from_sock(sk))))
goto out;
if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
goto out;
xprt_write_space(xprt);
}
out:
read_unlock(&sk->sk_callback_lock);
}
/**
* xs_tcp_write_space - callback invoked when socket buffer space
* becomes available
* @sk: socket whose state has changed
*
* Called when more output buffer space is available for this socket.
* We try not to wake our writers until they can make "significant"
* progress, otherwise we'll waste resources thrashing kernel_sendmsg
* with a bunch of small requests.
*/
static void xs_tcp_write_space(struct sock *sk)
{
read_lock(&sk->sk_callback_lock);
/* from net/core/stream.c:sk_stream_write_space */
if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) {
struct socket *sock;
struct rpc_xprt *xprt;
if (unlikely(!(sock = sk->sk_socket)))
goto out;
clear_bit(SOCK_NOSPACE, &sock->flags);
if (unlikely(!(xprt = xprt_from_sock(sk))))
goto out;
if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
goto out;
xprt_write_space(xprt);
}
out:
read_unlock(&sk->sk_callback_lock);
}
static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
struct sock *sk = transport->inet;
if (transport->rcvsize) {
sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
}
if (transport->sndsize) {
sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
sk->sk_write_space(sk);
}
}
/**
* xs_udp_set_buffer_size - set send and receive limits
* @xprt: generic transport
* @sndsize: requested size of send buffer, in bytes
* @rcvsize: requested size of receive buffer, in bytes
*
* Set socket send and receive buffer size limits.
*/
static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
transport->sndsize = 0;
if (sndsize)
transport->sndsize = sndsize + 1024;
transport->rcvsize = 0;
if (rcvsize)
transport->rcvsize = rcvsize + 1024;
xs_udp_do_set_buffer_size(xprt);
}
/**
* xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
* @task: task that timed out
*
* Adjust the congestion window after a retransmit timeout has occurred.
*/
static void xs_udp_timer(struct rpc_task *task)
{
xprt_adjust_cwnd(task, -ETIMEDOUT);
}
static unsigned short xs_get_random_port(void)
{
unsigned short range = xprt_max_resvport - xprt_min_resvport;
unsigned short rand = (unsigned short) net_random() % range;
return rand + xprt_min_resvport;
}
/**
* xs_set_port - reset the port number in the remote endpoint address
* @xprt: generic transport
* @port: new port number
*
*/
static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
{
struct sockaddr *addr = xs_addr(xprt);
dprintk("RPC: setting port for xprt %p to %u\n", xprt, port);
switch (addr->sa_family) {
case AF_INET:
((struct sockaddr_in *)addr)->sin_port = htons(port);
break;
case AF_INET6:
((struct sockaddr_in6 *)addr)->sin6_port = htons(port);
break;
default:
BUG();
}
}
static unsigned short xs_get_srcport(struct sock_xprt *transport, struct socket *sock)
{
unsigned short port = transport->port;
if (port == 0 && transport->xprt.resvport)
port = xs_get_random_port();
return port;
}
static unsigned short xs_next_srcport(struct sock_xprt *transport, struct socket *sock, unsigned short port)
{
if (transport->port != 0)
transport->port = 0;
if (!transport->xprt.resvport)
return 0;
if (port <= xprt_min_resvport || port > xprt_max_resvport)
return xprt_max_resvport;
return --port;
}
static int xs_bind4(struct sock_xprt *transport, struct socket *sock)
{
struct sockaddr_in myaddr = {
.sin_family = AF_INET,
};
struct sockaddr_in *sa;
int err, nloop = 0;
unsigned short port = xs_get_srcport(transport, sock);
unsigned short last;
sa = (struct sockaddr_in *)&transport->addr;
myaddr.sin_addr = sa->sin_addr;
do {
myaddr.sin_port = htons(port);
err = kernel_bind(sock, (struct sockaddr *) &myaddr,
sizeof(myaddr));
if (port == 0)
break;
if (err == 0) {
transport->port = port;
break;
}
last = port;
port = xs_next_srcport(transport, sock, port);
if (port > last)
nloop++;
} while (err == -EADDRINUSE && nloop != 2);
dprintk("RPC: %s "NIPQUAD_FMT":%u: %s (%d)\n",
__func__, NIPQUAD(myaddr.sin_addr),
port, err ? "failed" : "ok", err);
return err;
}
static int xs_bind6(struct sock_xprt *transport, struct socket *sock)
{
struct sockaddr_in6 myaddr = {
.sin6_family = AF_INET6,
};
struct sockaddr_in6 *sa;
int err, nloop = 0;
unsigned short port = xs_get_srcport(transport, sock);
unsigned short last;
sa = (struct sockaddr_in6 *)&transport->addr;
myaddr.sin6_addr = sa->sin6_addr;
do {
myaddr.sin6_port = htons(port);
err = kernel_bind(sock, (struct sockaddr *) &myaddr,
sizeof(myaddr));
if (port == 0)
break;
if (err == 0) {
transport->port = port;
break;
}
last = port;
port = xs_next_srcport(transport, sock, port);
if (port > last)
nloop++;
} while (err == -EADDRINUSE && nloop != 2);
dprintk("RPC: xs_bind6 "NIP6_FMT":%u: %s (%d)\n",
NIP6(myaddr.sin6_addr), port, err ? "failed" : "ok", err);
return err;
}
#ifdef CONFIG_DEBUG_LOCK_ALLOC
static struct lock_class_key xs_key[2];
static struct lock_class_key xs_slock_key[2];
static inline void xs_reclassify_socket4(struct socket *sock)
{
struct sock *sk = sock->sk;
BUG_ON(sock_owned_by_user(sk));
sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
&xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
}
static inline void xs_reclassify_socket6(struct socket *sock)
{
struct sock *sk = sock->sk;
BUG_ON(sock_owned_by_user(sk));
sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
&xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
}
#else
static inline void xs_reclassify_socket4(struct socket *sock)
{
}
static inline void xs_reclassify_socket6(struct socket *sock)
{
}
#endif
static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
if (!transport->inet) {
struct sock *sk = sock->sk;
write_lock_bh(&sk->sk_callback_lock);
sk->sk_user_data = xprt;
transport->old_data_ready = sk->sk_data_ready;
transport->old_state_change = sk->sk_state_change;
transport->old_write_space = sk->sk_write_space;
sk->sk_data_ready = xs_udp_data_ready;
sk->sk_write_space = xs_udp_write_space;
sk->sk_no_check = UDP_CSUM_NORCV;
sk->sk_allocation = GFP_ATOMIC;
xprt_set_connected(xprt);
/* Reset to new socket */
transport->sock = sock;
transport->inet = sk;
write_unlock_bh(&sk->sk_callback_lock);
}
xs_udp_do_set_buffer_size(xprt);
}
/**
* xs_udp_connect_worker4 - set up a UDP socket
* @work: RPC transport to connect
*
* Invoked by a work queue tasklet.
*/
static void xs_udp_connect_worker4(struct work_struct *work)
{
struct sock_xprt *transport =
container_of(work, struct sock_xprt, connect_worker.work);
struct rpc_xprt *xprt = &transport->xprt;
struct socket *sock = transport->sock;
int err, status = -EIO;
if (xprt->shutdown || !xprt_bound(xprt))
goto out;
/* Start by resetting any existing state */
xs_close(xprt);
if ((err = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock)) < 0) {
dprintk("RPC: can't create UDP transport socket (%d).\n", -err);
goto out;
}
xs_reclassify_socket4(sock);
if (xs_bind4(transport, sock)) {
sock_release(sock);
goto out;
}
dprintk("RPC: worker connecting xprt %p to address: %s\n",
xprt, xprt->address_strings[RPC_DISPLAY_ALL]);
xs_udp_finish_connecting(xprt, sock);
status = 0;
out:
xprt_wake_pending_tasks(xprt, status);
xprt_clear_connecting(xprt);
}
/**
* xs_udp_connect_worker6 - set up a UDP socket
* @work: RPC transport to connect
*
* Invoked by a work queue tasklet.
*/
static void xs_udp_connect_worker6(struct work_struct *work)
{
struct sock_xprt *transport =
container_of(work, struct sock_xprt, connect_worker.work);
struct rpc_xprt *xprt = &transport->xprt;
struct socket *sock = transport->sock;
int err, status = -EIO;
if (xprt->shutdown || !xprt_bound(xprt))
goto out;
/* Start by resetting any existing state */
xs_close(xprt);
if ((err = sock_create_kern(PF_INET6, SOCK_DGRAM, IPPROTO_UDP, &sock)) < 0) {
dprintk("RPC: can't create UDP transport socket (%d).\n", -err);
goto out;
}
xs_reclassify_socket6(sock);
if (xs_bind6(transport, sock) < 0) {
sock_release(sock);
goto out;
}
dprintk("RPC: worker connecting xprt %p to address: %s\n",
xprt, xprt->address_strings[RPC_DISPLAY_ALL]);
xs_udp_finish_connecting(xprt, sock);
status = 0;
out:
xprt_wake_pending_tasks(xprt, status);
xprt_clear_connecting(xprt);
}
/*
* We need to preserve the port number so the reply cache on the server can
* find our cached RPC replies when we get around to reconnecting.
*/
static void xs_tcp_reuse_connection(struct rpc_xprt *xprt)
{
int result;
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
struct sockaddr any;
dprintk("RPC: disconnecting xprt %p to reuse port\n", xprt);
/*
* Disconnect the transport socket by doing a connect operation
* with AF_UNSPEC. This should return immediately...
*/
memset(&any, 0, sizeof(any));
any.sa_family = AF_UNSPEC;
result = kernel_connect(transport->sock, &any, sizeof(any), 0);
if (result)
dprintk("RPC: AF_UNSPEC connect return code %d\n",
result);
}
static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
if (!transport->inet) {
struct sock *sk = sock->sk;
write_lock_bh(&sk->sk_callback_lock);
sk->sk_user_data = xprt;
transport->old_data_ready = sk->sk_data_ready;
transport->old_state_change = sk->sk_state_change;
transport->old_write_space = sk->sk_write_space;
sk->sk_data_ready = xs_tcp_data_ready;
sk->sk_state_change = xs_tcp_state_change;
sk->sk_write_space = xs_tcp_write_space;
sk->sk_allocation = GFP_ATOMIC;
/* socket options */
sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
sock_reset_flag(sk, SOCK_LINGER);
tcp_sk(sk)->linger2 = 0;
tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
xprt_clear_connected(xprt);
/* Reset to new socket */
transport->sock = sock;
transport->inet = sk;
write_unlock_bh(&sk->sk_callback_lock);
}
/* Tell the socket layer to start connecting... */
xprt->stat.connect_count++;
xprt->stat.connect_start = jiffies;
return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
}
/**
* xs_tcp_connect_worker4 - connect a TCP socket to a remote endpoint
* @work: RPC transport to connect
*
* Invoked by a work queue tasklet.
*/
static void xs_tcp_connect_worker4(struct work_struct *work)
{
struct sock_xprt *transport =
container_of(work, struct sock_xprt, connect_worker.work);
struct rpc_xprt *xprt = &transport->xprt;
struct socket *sock = transport->sock;
int err, status = -EIO;
if (xprt->shutdown || !xprt_bound(xprt))
goto out;
if (!sock) {
/* start from scratch */
if ((err = sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock)) < 0) {
dprintk("RPC: can't create TCP transport socket (%d).\n", -err);
goto out;
}
xs_reclassify_socket4(sock);
if (xs_bind4(transport, sock) < 0) {
sock_release(sock);
goto out;
}
} else
/* "close" the socket, preserving the local port */
xs_tcp_reuse_connection(xprt);
dprintk("RPC: worker connecting xprt %p to address: %s\n",
xprt, xprt->address_strings[RPC_DISPLAY_ALL]);
status = xs_tcp_finish_connecting(xprt, sock);
dprintk("RPC: %p connect status %d connected %d sock state %d\n",
xprt, -status, xprt_connected(xprt),
sock->sk->sk_state);
if (status < 0) {
switch (status) {
case -EINPROGRESS:
case -EALREADY:
goto out_clear;
case -ECONNREFUSED:
case -ECONNRESET:
/* retry with existing socket, after a delay */
break;
default:
/* get rid of existing socket, and retry */
xs_tcp_shutdown(xprt);
}
}
out:
xprt_wake_pending_tasks(xprt, status);
out_clear:
xprt_clear_connecting(xprt);
}
/**
* xs_tcp_connect_worker6 - connect a TCP socket to a remote endpoint
* @work: RPC transport to connect
*
* Invoked by a work queue tasklet.
*/
static void xs_tcp_connect_worker6(struct work_struct *work)
{
struct sock_xprt *transport =
container_of(work, struct sock_xprt, connect_worker.work);
struct rpc_xprt *xprt = &transport->xprt;
struct socket *sock = transport->sock;
int err, status = -EIO;
if (xprt->shutdown || !xprt_bound(xprt))
goto out;
if (!sock) {
/* start from scratch */
if ((err = sock_create_kern(PF_INET6, SOCK_STREAM, IPPROTO_TCP, &sock)) < 0) {
dprintk("RPC: can't create TCP transport socket (%d).\n", -err);
goto out;
}
xs_reclassify_socket6(sock);
if (xs_bind6(transport, sock) < 0) {
sock_release(sock);
goto out;
}
} else
/* "close" the socket, preserving the local port */
xs_tcp_reuse_connection(xprt);
dprintk("RPC: worker connecting xprt %p to address: %s\n",
xprt, xprt->address_strings[RPC_DISPLAY_ALL]);
status = xs_tcp_finish_connecting(xprt, sock);
dprintk("RPC: %p connect status %d connected %d sock state %d\n",
xprt, -status, xprt_connected(xprt), sock->sk->sk_state);
if (status < 0) {
switch (status) {
case -EINPROGRESS:
case -EALREADY:
goto out_clear;
case -ECONNREFUSED:
case -ECONNRESET:
/* retry with existing socket, after a delay */
break;
default:
/* get rid of existing socket, and retry */
xs_tcp_shutdown(xprt);
}
}
out:
xprt_wake_pending_tasks(xprt, status);
out_clear:
xprt_clear_connecting(xprt);
}
/**
* xs_connect - connect a socket to a remote endpoint
* @task: address of RPC task that manages state of connect request
*
* TCP: If the remote end dropped the connection, delay reconnecting.
*
* UDP socket connects are synchronous, but we use a work queue anyway
* to guarantee that even unprivileged user processes can set up a
* socket on a privileged port.
*
* If a UDP socket connect fails, the delay behavior here prevents
* retry floods (hard mounts).
*/
static void xs_connect(struct rpc_task *task)
{
struct rpc_xprt *xprt = task->tk_xprt;
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
if (xprt_test_and_set_connecting(xprt))
return;
if (transport->sock != NULL) {
dprintk("RPC: xs_connect delayed xprt %p for %lu "
"seconds\n",
xprt, xprt->reestablish_timeout / HZ);
queue_delayed_work(rpciod_workqueue,
&transport->connect_worker,
xprt->reestablish_timeout);
xprt->reestablish_timeout <<= 1;
if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
} else {
dprintk("RPC: xs_connect scheduled xprt %p\n", xprt);
queue_delayed_work(rpciod_workqueue,
&transport->connect_worker, 0);
}
}
static void xs_tcp_connect(struct rpc_task *task)
{
struct rpc_xprt *xprt = task->tk_xprt;
/* Initiate graceful shutdown of the socket if not already done */
if (test_bit(XPRT_CONNECTED, &xprt->state))
xs_tcp_shutdown(xprt);
/* Exit if we need to wait for socket shutdown to complete */
if (test_bit(XPRT_CLOSING, &xprt->state))
return;
xs_connect(task);
}
/**
* xs_udp_print_stats - display UDP socket-specifc stats
* @xprt: rpc_xprt struct containing statistics
* @seq: output file
*
*/
static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %Lu %Lu\n",
transport->port,
xprt->stat.bind_count,
xprt->stat.sends,
xprt->stat.recvs,
xprt->stat.bad_xids,
xprt->stat.req_u,
xprt->stat.bklog_u);
}
/**
* xs_tcp_print_stats - display TCP socket-specifc stats
* @xprt: rpc_xprt struct containing statistics
* @seq: output file
*
*/
static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
long idle_time = 0;
if (xprt_connected(xprt))
idle_time = (long)(jiffies - xprt->last_used) / HZ;
seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu %Lu %Lu\n",
transport->port,
xprt->stat.bind_count,
xprt->stat.connect_count,
xprt->stat.connect_time,
idle_time,
xprt->stat.sends,
xprt->stat.recvs,
xprt->stat.bad_xids,
xprt->stat.req_u,
xprt->stat.bklog_u);
}
static struct rpc_xprt_ops xs_udp_ops = {
.set_buffer_size = xs_udp_set_buffer_size,
.reserve_xprt = xprt_reserve_xprt_cong,
.release_xprt = xprt_release_xprt_cong,
.rpcbind = rpcb_getport_async,
.set_port = xs_set_port,
.connect = xs_connect,
.buf_alloc = rpc_malloc,
.buf_free = rpc_free,
.send_request = xs_udp_send_request,
.set_retrans_timeout = xprt_set_retrans_timeout_rtt,
.timer = xs_udp_timer,
.release_request = xprt_release_rqst_cong,
.close = xs_close,
.destroy = xs_destroy,
.print_stats = xs_udp_print_stats,
};
static struct rpc_xprt_ops xs_tcp_ops = {
.reserve_xprt = xprt_reserve_xprt,
.release_xprt = xs_tcp_release_xprt,
.rpcbind = rpcb_getport_async,
.set_port = xs_set_port,
.connect = xs_tcp_connect,
.buf_alloc = rpc_malloc,
.buf_free = rpc_free,
.send_request = xs_tcp_send_request,
.set_retrans_timeout = xprt_set_retrans_timeout_def,
.close = xs_tcp_shutdown,
.destroy = xs_destroy,
.print_stats = xs_tcp_print_stats,
};
static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
unsigned int slot_table_size)
{
struct rpc_xprt *xprt;
struct sock_xprt *new;
if (args->addrlen > sizeof(xprt->addr)) {
dprintk("RPC: xs_setup_xprt: address too large\n");
return ERR_PTR(-EBADF);
}
new = kzalloc(sizeof(*new), GFP_KERNEL);
if (new == NULL) {
dprintk("RPC: xs_setup_xprt: couldn't allocate "
"rpc_xprt\n");
return ERR_PTR(-ENOMEM);
}
xprt = &new->xprt;
xprt->max_reqs = slot_table_size;
xprt->slot = kcalloc(xprt->max_reqs, sizeof(struct rpc_rqst), GFP_KERNEL);
if (xprt->slot == NULL) {
kfree(xprt);
dprintk("RPC: xs_setup_xprt: couldn't allocate slot "
"table\n");
return ERR_PTR(-ENOMEM);
}
memcpy(&xprt->addr, args->dstaddr, args->addrlen);
xprt->addrlen = args->addrlen;
if (args->srcaddr)
memcpy(&new->addr, args->srcaddr, args->addrlen);
return xprt;
}
static const struct rpc_timeout xs_udp_default_timeout = {
.to_initval = 5 * HZ,
.to_maxval = 30 * HZ,
.to_increment = 5 * HZ,
.to_retries = 5,
};
/**
* xs_setup_udp - Set up transport to use a UDP socket
* @args: rpc transport creation arguments
*
*/
static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
{
struct sockaddr *addr = args->dstaddr;
struct rpc_xprt *xprt;
struct sock_xprt *transport;
xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries);
if (IS_ERR(xprt))
return xprt;
transport = container_of(xprt, struct sock_xprt, xprt);
xprt->prot = IPPROTO_UDP;
xprt->tsh_size = 0;
/* XXX: header size can vary due to auth type, IPv6, etc. */
xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
xprt->bind_timeout = XS_BIND_TO;
xprt->connect_timeout = XS_UDP_CONN_TO;
xprt->reestablish_timeout = XS_UDP_REEST_TO;
xprt->idle_timeout = XS_IDLE_DISC_TO;
xprt->ops = &xs_udp_ops;
xprt->timeout = &xs_udp_default_timeout;
switch (addr->sa_family) {
case AF_INET:
if (((struct sockaddr_in *)addr)->sin_port != htons(0))
xprt_set_bound(xprt);
INIT_DELAYED_WORK(&transport->connect_worker,
xs_udp_connect_worker4);
xs_format_ipv4_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
break;
case AF_INET6:
if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
xprt_set_bound(xprt);
INIT_DELAYED_WORK(&transport->connect_worker,
xs_udp_connect_worker6);
xs_format_ipv6_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
break;
default:
kfree(xprt);
return ERR_PTR(-EAFNOSUPPORT);
}
dprintk("RPC: set up transport to address %s\n",
xprt->address_strings[RPC_DISPLAY_ALL]);
if (try_module_get(THIS_MODULE))
return xprt;
kfree(xprt->slot);
kfree(xprt);
return ERR_PTR(-EINVAL);
}
static const struct rpc_timeout xs_tcp_default_timeout = {
.to_initval = 60 * HZ,
.to_maxval = 60 * HZ,
.to_retries = 2,
};
/**
* xs_setup_tcp - Set up transport to use a TCP socket
* @args: rpc transport creation arguments
*
*/
static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
{
struct sockaddr *addr = args->dstaddr;
struct rpc_xprt *xprt;
struct sock_xprt *transport;
xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
if (IS_ERR(xprt))
return xprt;
transport = container_of(xprt, struct sock_xprt, xprt);
xprt->prot = IPPROTO_TCP;
xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
xprt->bind_timeout = XS_BIND_TO;
xprt->connect_timeout = XS_TCP_CONN_TO;
xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
xprt->idle_timeout = XS_IDLE_DISC_TO;
xprt->ops = &xs_tcp_ops;
xprt->timeout = &xs_tcp_default_timeout;
switch (addr->sa_family) {
case AF_INET:
if (((struct sockaddr_in *)addr)->sin_port != htons(0))
xprt_set_bound(xprt);
INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_connect_worker4);
xs_format_ipv4_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
break;
case AF_INET6:
if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
xprt_set_bound(xprt);
INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_connect_worker6);
xs_format_ipv6_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
break;
default:
kfree(xprt);
return ERR_PTR(-EAFNOSUPPORT);
}
dprintk("RPC: set up transport to address %s\n",
xprt->address_strings[RPC_DISPLAY_ALL]);
if (try_module_get(THIS_MODULE))
return xprt;
kfree(xprt->slot);
kfree(xprt);
return ERR_PTR(-EINVAL);
}
static struct xprt_class xs_udp_transport = {
.list = LIST_HEAD_INIT(xs_udp_transport.list),
.name = "udp",
.owner = THIS_MODULE,
.ident = IPPROTO_UDP,
.setup = xs_setup_udp,
};
static struct xprt_class xs_tcp_transport = {
.list = LIST_HEAD_INIT(xs_tcp_transport.list),
.name = "tcp",
.owner = THIS_MODULE,
.ident = IPPROTO_TCP,
.setup = xs_setup_tcp,
};
/**
* init_socket_xprt - set up xprtsock's sysctls, register with RPC client
*
*/
int init_socket_xprt(void)
{
#ifdef RPC_DEBUG
if (!sunrpc_table_header)
sunrpc_table_header = register_sysctl_table(sunrpc_table);
#endif
xprt_register_transport(&xs_udp_transport);
xprt_register_transport(&xs_tcp_transport);
return 0;
}
/**
* cleanup_socket_xprt - remove xprtsock's sysctls, unregister
*
*/
void cleanup_socket_xprt(void)
{
#ifdef RPC_DEBUG
if (sunrpc_table_header) {
unregister_sysctl_table(sunrpc_table_header);
sunrpc_table_header = NULL;
}
#endif
xprt_unregister_transport(&xs_udp_transport);
xprt_unregister_transport(&xs_tcp_transport);
}