linux/net/sunrpc/svcsock.c
Chuck Lever c0401ea008 SUNRPC: Update RPC server's TCP record marker decoder
Clean up: Update the RPC server's TCP record marker decoder to match the
constructs used by the RPC client's TCP socket transport.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-04-23 16:13:43 -04:00

1289 lines
34 KiB
C

/*
* linux/net/sunrpc/svcsock.c
*
* These are the RPC server socket internals.
*
* The server scheduling algorithm does not always distribute the load
* evenly when servicing a single client. May need to modify the
* svc_xprt_enqueue procedure...
*
* TCP support is largely untested and may be a little slow. The problem
* is that we currently do two separate recvfrom's, one for the 4-byte
* record length, and the second for the actual record. This could possibly
* be improved by always reading a minimum size of around 100 bytes and
* tucking any superfluous bytes away in a temporary store. Still, that
* leaves write requests out in the rain. An alternative may be to peek at
* the first skb in the queue, and if it matches the next TCP sequence
* number, to extract the record marker. Yuck.
*
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/fcntl.h>
#include <linux/net.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/udp.h>
#include <linux/tcp.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/file.h>
#include <linux/freezer.h>
#include <net/sock.h>
#include <net/checksum.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/tcp.h>
#include <net/tcp_states.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include <linux/sunrpc/types.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/msg_prot.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/stats.h>
#define RPCDBG_FACILITY RPCDBG_SVCXPRT
static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
int *errp, int flags);
static void svc_udp_data_ready(struct sock *, int);
static int svc_udp_recvfrom(struct svc_rqst *);
static int svc_udp_sendto(struct svc_rqst *);
static void svc_sock_detach(struct svc_xprt *);
static void svc_sock_free(struct svc_xprt *);
static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
struct sockaddr *, int, int);
#ifdef CONFIG_DEBUG_LOCK_ALLOC
static struct lock_class_key svc_key[2];
static struct lock_class_key svc_slock_key[2];
static void svc_reclassify_socket(struct socket *sock)
{
struct sock *sk = sock->sk;
BUG_ON(sock_owned_by_user(sk));
switch (sk->sk_family) {
case AF_INET:
sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
&svc_slock_key[0],
"sk_xprt.xpt_lock-AF_INET-NFSD",
&svc_key[0]);
break;
case AF_INET6:
sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
&svc_slock_key[1],
"sk_xprt.xpt_lock-AF_INET6-NFSD",
&svc_key[1]);
break;
default:
BUG();
}
}
#else
static void svc_reclassify_socket(struct socket *sock)
{
}
#endif
/*
* Release an skbuff after use
*/
static void svc_release_skb(struct svc_rqst *rqstp)
{
struct sk_buff *skb = rqstp->rq_xprt_ctxt;
struct svc_deferred_req *dr = rqstp->rq_deferred;
if (skb) {
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
rqstp->rq_xprt_ctxt = NULL;
dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
skb_free_datagram(svsk->sk_sk, skb);
}
if (dr) {
rqstp->rq_deferred = NULL;
kfree(dr);
}
}
union svc_pktinfo_u {
struct in_pktinfo pkti;
struct in6_pktinfo pkti6;
};
#define SVC_PKTINFO_SPACE \
CMSG_SPACE(sizeof(union svc_pktinfo_u))
static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
{
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
switch (svsk->sk_sk->sk_family) {
case AF_INET: {
struct in_pktinfo *pki = CMSG_DATA(cmh);
cmh->cmsg_level = SOL_IP;
cmh->cmsg_type = IP_PKTINFO;
pki->ipi_ifindex = 0;
pki->ipi_spec_dst.s_addr = rqstp->rq_daddr.addr.s_addr;
cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
}
break;
case AF_INET6: {
struct in6_pktinfo *pki = CMSG_DATA(cmh);
cmh->cmsg_level = SOL_IPV6;
cmh->cmsg_type = IPV6_PKTINFO;
pki->ipi6_ifindex = 0;
ipv6_addr_copy(&pki->ipi6_addr,
&rqstp->rq_daddr.addr6);
cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
}
break;
}
return;
}
/*
* Generic sendto routine
*/
static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
{
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
struct socket *sock = svsk->sk_sock;
int slen;
union {
struct cmsghdr hdr;
long all[SVC_PKTINFO_SPACE / sizeof(long)];
} buffer;
struct cmsghdr *cmh = &buffer.hdr;
int len = 0;
int result;
int size;
struct page **ppage = xdr->pages;
size_t base = xdr->page_base;
unsigned int pglen = xdr->page_len;
unsigned int flags = MSG_MORE;
RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
slen = xdr->len;
if (rqstp->rq_prot == IPPROTO_UDP) {
struct msghdr msg = {
.msg_name = &rqstp->rq_addr,
.msg_namelen = rqstp->rq_addrlen,
.msg_control = cmh,
.msg_controllen = sizeof(buffer),
.msg_flags = MSG_MORE,
};
svc_set_cmsg_data(rqstp, cmh);
if (sock_sendmsg(sock, &msg, 0) < 0)
goto out;
}
/* send head */
if (slen == xdr->head[0].iov_len)
flags = 0;
len = kernel_sendpage(sock, rqstp->rq_respages[0], 0,
xdr->head[0].iov_len, flags);
if (len != xdr->head[0].iov_len)
goto out;
slen -= xdr->head[0].iov_len;
if (slen == 0)
goto out;
/* send page data */
size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
while (pglen > 0) {
if (slen == size)
flags = 0;
result = kernel_sendpage(sock, *ppage, base, size, flags);
if (result > 0)
len += result;
if (result != size)
goto out;
slen -= size;
pglen -= size;
size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
base = 0;
ppage++;
}
/* send tail */
if (xdr->tail[0].iov_len) {
result = kernel_sendpage(sock, rqstp->rq_respages[0],
((unsigned long)xdr->tail[0].iov_base)
& (PAGE_SIZE-1),
xdr->tail[0].iov_len, 0);
if (result > 0)
len += result;
}
out:
dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n",
svsk, xdr->head[0].iov_base, xdr->head[0].iov_len,
xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf)));
return len;
}
/*
* Report socket names for nfsdfs
*/
static int one_sock_name(char *buf, struct svc_sock *svsk)
{
int len;
switch(svsk->sk_sk->sk_family) {
case AF_INET:
len = sprintf(buf, "ipv4 %s %u.%u.%u.%u %d\n",
svsk->sk_sk->sk_protocol==IPPROTO_UDP?
"udp" : "tcp",
NIPQUAD(inet_sk(svsk->sk_sk)->rcv_saddr),
inet_sk(svsk->sk_sk)->num);
break;
default:
len = sprintf(buf, "*unknown-%d*\n",
svsk->sk_sk->sk_family);
}
return len;
}
int
svc_sock_names(char *buf, struct svc_serv *serv, char *toclose)
{
struct svc_sock *svsk, *closesk = NULL;
int len = 0;
if (!serv)
return 0;
spin_lock_bh(&serv->sv_lock);
list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list) {
int onelen = one_sock_name(buf+len, svsk);
if (toclose && strcmp(toclose, buf+len) == 0)
closesk = svsk;
else
len += onelen;
}
spin_unlock_bh(&serv->sv_lock);
if (closesk)
/* Should unregister with portmap, but you cannot
* unregister just one protocol...
*/
svc_close_xprt(&closesk->sk_xprt);
else if (toclose)
return -ENOENT;
return len;
}
EXPORT_SYMBOL(svc_sock_names);
/*
* Check input queue length
*/
static int svc_recv_available(struct svc_sock *svsk)
{
struct socket *sock = svsk->sk_sock;
int avail, err;
err = kernel_sock_ioctl(sock, TIOCINQ, (unsigned long) &avail);
return (err >= 0)? avail : err;
}
/*
* Generic recvfrom routine.
*/
static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
int buflen)
{
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
struct msghdr msg = {
.msg_flags = MSG_DONTWAIT,
};
int len;
rqstp->rq_xprt_hlen = 0;
len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
msg.msg_flags);
dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
svsk, iov[0].iov_base, iov[0].iov_len, len);
return len;
}
/*
* Set socket snd and rcv buffer lengths
*/
static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
unsigned int rcv)
{
#if 0
mm_segment_t oldfs;
oldfs = get_fs(); set_fs(KERNEL_DS);
sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
(char*)&snd, sizeof(snd));
sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
(char*)&rcv, sizeof(rcv));
#else
/* sock_setsockopt limits use to sysctl_?mem_max,
* which isn't acceptable. Until that is made conditional
* on not having CAP_SYS_RESOURCE or similar, we go direct...
* DaveM said I could!
*/
lock_sock(sock->sk);
sock->sk->sk_sndbuf = snd * 2;
sock->sk->sk_rcvbuf = rcv * 2;
sock->sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK;
release_sock(sock->sk);
#endif
}
/*
* INET callback when data has been received on the socket.
*/
static void svc_udp_data_ready(struct sock *sk, int count)
{
struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
if (svsk) {
dprintk("svc: socket %p(inet %p), count=%d, busy=%d\n",
svsk, sk, count,
test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
svc_xprt_enqueue(&svsk->sk_xprt);
}
if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
wake_up_interruptible(sk->sk_sleep);
}
/*
* INET callback when space is newly available on the socket.
*/
static void svc_write_space(struct sock *sk)
{
struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
if (svsk) {
dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
svc_xprt_enqueue(&svsk->sk_xprt);
}
if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) {
dprintk("RPC svc_write_space: someone sleeping on %p\n",
svsk);
wake_up_interruptible(sk->sk_sleep);
}
}
/*
* Copy the UDP datagram's destination address to the rqstp structure.
* The 'destination' address in this case is the address to which the
* peer sent the datagram, i.e. our local address. For multihomed
* hosts, this can change from msg to msg. Note that only the IP
* address changes, the port number should remain the same.
*/
static void svc_udp_get_dest_address(struct svc_rqst *rqstp,
struct cmsghdr *cmh)
{
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
switch (svsk->sk_sk->sk_family) {
case AF_INET: {
struct in_pktinfo *pki = CMSG_DATA(cmh);
rqstp->rq_daddr.addr.s_addr = pki->ipi_spec_dst.s_addr;
break;
}
case AF_INET6: {
struct in6_pktinfo *pki = CMSG_DATA(cmh);
ipv6_addr_copy(&rqstp->rq_daddr.addr6, &pki->ipi6_addr);
break;
}
}
}
/*
* Receive a datagram from a UDP socket.
*/
static int svc_udp_recvfrom(struct svc_rqst *rqstp)
{
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
struct svc_serv *serv = svsk->sk_xprt.xpt_server;
struct sk_buff *skb;
union {
struct cmsghdr hdr;
long all[SVC_PKTINFO_SPACE / sizeof(long)];
} buffer;
struct cmsghdr *cmh = &buffer.hdr;
int err, len;
struct msghdr msg = {
.msg_name = svc_addr(rqstp),
.msg_control = cmh,
.msg_controllen = sizeof(buffer),
.msg_flags = MSG_DONTWAIT,
};
if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
/* udp sockets need large rcvbuf as all pending
* requests are still in that buffer. sndbuf must
* also be large enough that there is enough space
* for one reply per thread. We count all threads
* rather than threads in a particular pool, which
* provides an upper bound on the number of threads
* which will access the socket.
*/
svc_sock_setbufsize(svsk->sk_sock,
(serv->sv_nrthreads+3) * serv->sv_max_mesg,
(serv->sv_nrthreads+3) * serv->sv_max_mesg);
clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
skb = NULL;
err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
0, 0, MSG_PEEK | MSG_DONTWAIT);
if (err >= 0)
skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err);
if (skb == NULL) {
if (err != -EAGAIN) {
/* possibly an icmp error */
dprintk("svc: recvfrom returned error %d\n", -err);
set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
}
svc_xprt_received(&svsk->sk_xprt);
return -EAGAIN;
}
len = svc_addr_len(svc_addr(rqstp));
if (len < 0)
return len;
rqstp->rq_addrlen = len;
if (skb->tstamp.tv64 == 0) {
skb->tstamp = ktime_get_real();
/* Don't enable netstamp, sunrpc doesn't
need that much accuracy */
}
svsk->sk_sk->sk_stamp = skb->tstamp;
set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
/*
* Maybe more packets - kick another thread ASAP.
*/
svc_xprt_received(&svsk->sk_xprt);
len = skb->len - sizeof(struct udphdr);
rqstp->rq_arg.len = len;
rqstp->rq_prot = IPPROTO_UDP;
if (cmh->cmsg_level != IPPROTO_IP ||
cmh->cmsg_type != IP_PKTINFO) {
if (net_ratelimit())
printk("rpcsvc: received unknown control message:"
"%d/%d\n",
cmh->cmsg_level, cmh->cmsg_type);
skb_free_datagram(svsk->sk_sk, skb);
return 0;
}
svc_udp_get_dest_address(rqstp, cmh);
if (skb_is_nonlinear(skb)) {
/* we have to copy */
local_bh_disable();
if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
local_bh_enable();
/* checksum error */
skb_free_datagram(svsk->sk_sk, skb);
return 0;
}
local_bh_enable();
skb_free_datagram(svsk->sk_sk, skb);
} else {
/* we can use it in-place */
rqstp->rq_arg.head[0].iov_base = skb->data +
sizeof(struct udphdr);
rqstp->rq_arg.head[0].iov_len = len;
if (skb_checksum_complete(skb)) {
skb_free_datagram(svsk->sk_sk, skb);
return 0;
}
rqstp->rq_xprt_ctxt = skb;
}
rqstp->rq_arg.page_base = 0;
if (len <= rqstp->rq_arg.head[0].iov_len) {
rqstp->rq_arg.head[0].iov_len = len;
rqstp->rq_arg.page_len = 0;
rqstp->rq_respages = rqstp->rq_pages+1;
} else {
rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
rqstp->rq_respages = rqstp->rq_pages + 1 +
DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
}
if (serv->sv_stats)
serv->sv_stats->netudpcnt++;
return len;
}
static int
svc_udp_sendto(struct svc_rqst *rqstp)
{
int error;
error = svc_sendto(rqstp, &rqstp->rq_res);
if (error == -ECONNREFUSED)
/* ICMP error on earlier request. */
error = svc_sendto(rqstp, &rqstp->rq_res);
return error;
}
static void svc_udp_prep_reply_hdr(struct svc_rqst *rqstp)
{
}
static int svc_udp_has_wspace(struct svc_xprt *xprt)
{
struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
struct svc_serv *serv = xprt->xpt_server;
unsigned long required;
/*
* Set the SOCK_NOSPACE flag before checking the available
* sock space.
*/
set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
if (required*2 > sock_wspace(svsk->sk_sk))
return 0;
clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
return 1;
}
static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
{
BUG();
return NULL;
}
static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
struct sockaddr *sa, int salen,
int flags)
{
return svc_create_socket(serv, IPPROTO_UDP, sa, salen, flags);
}
static struct svc_xprt_ops svc_udp_ops = {
.xpo_create = svc_udp_create,
.xpo_recvfrom = svc_udp_recvfrom,
.xpo_sendto = svc_udp_sendto,
.xpo_release_rqst = svc_release_skb,
.xpo_detach = svc_sock_detach,
.xpo_free = svc_sock_free,
.xpo_prep_reply_hdr = svc_udp_prep_reply_hdr,
.xpo_has_wspace = svc_udp_has_wspace,
.xpo_accept = svc_udp_accept,
};
static struct svc_xprt_class svc_udp_class = {
.xcl_name = "udp",
.xcl_owner = THIS_MODULE,
.xcl_ops = &svc_udp_ops,
.xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
};
static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
{
int one = 1;
mm_segment_t oldfs;
svc_xprt_init(&svc_udp_class, &svsk->sk_xprt, serv);
clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
svsk->sk_sk->sk_data_ready = svc_udp_data_ready;
svsk->sk_sk->sk_write_space = svc_write_space;
/* initialise setting must have enough space to
* receive and respond to one request.
* svc_udp_recvfrom will re-adjust if necessary
*/
svc_sock_setbufsize(svsk->sk_sock,
3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
/* data might have come in before data_ready set up */
set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
oldfs = get_fs();
set_fs(KERNEL_DS);
/* make sure we get destination address info */
svsk->sk_sock->ops->setsockopt(svsk->sk_sock, IPPROTO_IP, IP_PKTINFO,
(char __user *)&one, sizeof(one));
set_fs(oldfs);
}
/*
* A data_ready event on a listening socket means there's a connection
* pending. Do not use state_change as a substitute for it.
*/
static void svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
{
struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
dprintk("svc: socket %p TCP (listen) state change %d\n",
sk, sk->sk_state);
/*
* This callback may called twice when a new connection
* is established as a child socket inherits everything
* from a parent LISTEN socket.
* 1) data_ready method of the parent socket will be called
* when one of child sockets become ESTABLISHED.
* 2) data_ready method of the child socket may be called
* when it receives data before the socket is accepted.
* In case of 2, we should ignore it silently.
*/
if (sk->sk_state == TCP_LISTEN) {
if (svsk) {
set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
svc_xprt_enqueue(&svsk->sk_xprt);
} else
printk("svc: socket %p: no user data\n", sk);
}
if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
wake_up_interruptible_all(sk->sk_sleep);
}
/*
* A state change on a connected socket means it's dying or dead.
*/
static void svc_tcp_state_change(struct sock *sk)
{
struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
sk, sk->sk_state, sk->sk_user_data);
if (!svsk)
printk("svc: socket %p: no user data\n", sk);
else {
set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
svc_xprt_enqueue(&svsk->sk_xprt);
}
if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
wake_up_interruptible_all(sk->sk_sleep);
}
static void svc_tcp_data_ready(struct sock *sk, int count)
{
struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
dprintk("svc: socket %p TCP data ready (svsk %p)\n",
sk, sk->sk_user_data);
if (svsk) {
set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
svc_xprt_enqueue(&svsk->sk_xprt);
}
if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
wake_up_interruptible(sk->sk_sleep);
}
/*
* Accept a TCP connection
*/
static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
{
struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
struct sockaddr_storage addr;
struct sockaddr *sin = (struct sockaddr *) &addr;
struct svc_serv *serv = svsk->sk_xprt.xpt_server;
struct socket *sock = svsk->sk_sock;
struct socket *newsock;
struct svc_sock *newsvsk;
int err, slen;
RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
if (!sock)
return NULL;
clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
err = kernel_accept(sock, &newsock, O_NONBLOCK);
if (err < 0) {
if (err == -ENOMEM)
printk(KERN_WARNING "%s: no more sockets!\n",
serv->sv_name);
else if (err != -EAGAIN && net_ratelimit())
printk(KERN_WARNING "%s: accept failed (err %d)!\n",
serv->sv_name, -err);
return NULL;
}
set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
err = kernel_getpeername(newsock, sin, &slen);
if (err < 0) {
if (net_ratelimit())
printk(KERN_WARNING "%s: peername failed (err %d)!\n",
serv->sv_name, -err);
goto failed; /* aborted connection or whatever */
}
/* Ideally, we would want to reject connections from unauthorized
* hosts here, but when we get encryption, the IP of the host won't
* tell us anything. For now just warn about unpriv connections.
*/
if (!svc_port_is_privileged(sin)) {
dprintk(KERN_WARNING
"%s: connect from unprivileged port: %s\n",
serv->sv_name,
__svc_print_addr(sin, buf, sizeof(buf)));
}
dprintk("%s: connect from %s\n", serv->sv_name,
__svc_print_addr(sin, buf, sizeof(buf)));
/* make sure that a write doesn't block forever when
* low on memory
*/
newsock->sk->sk_sndtimeo = HZ*30;
if (!(newsvsk = svc_setup_socket(serv, newsock, &err,
(SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY))))
goto failed;
svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen);
err = kernel_getsockname(newsock, sin, &slen);
if (unlikely(err < 0)) {
dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err);
slen = offsetof(struct sockaddr, sa_data);
}
svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen);
if (serv->sv_stats)
serv->sv_stats->nettcpconn++;
return &newsvsk->sk_xprt;
failed:
sock_release(newsock);
return NULL;
}
/*
* Receive data from a TCP socket.
*/
static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
{
struct svc_sock *svsk =
container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
struct svc_serv *serv = svsk->sk_xprt.xpt_server;
int len;
struct kvec *vec;
int pnum, vlen;
dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
/* sndbuf needs to have room for one request
* per thread, otherwise we can stall even when the
* network isn't a bottleneck.
*
* We count all threads rather than threads in a
* particular pool, which provides an upper bound
* on the number of threads which will access the socket.
*
* rcvbuf just needs to be able to hold a few requests.
* Normally they will be removed from the queue
* as soon a a complete request arrives.
*/
svc_sock_setbufsize(svsk->sk_sock,
(serv->sv_nrthreads+3) * serv->sv_max_mesg,
3 * serv->sv_max_mesg);
clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
/* Receive data. If we haven't got the record length yet, get
* the next four bytes. Otherwise try to gobble up as much as
* possible up to the complete record length.
*/
if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
int want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
struct kvec iov;
iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
iov.iov_len = want;
if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0)
goto error;
svsk->sk_tcplen += len;
if (len < want) {
dprintk("svc: short recvfrom while reading record "
"length (%d of %d)\n", len, want);
svc_xprt_received(&svsk->sk_xprt);
return -EAGAIN; /* record header not complete */
}
svsk->sk_reclen = ntohl(svsk->sk_reclen);
if (!(svsk->sk_reclen & RPC_LAST_STREAM_FRAGMENT)) {
/* FIXME: technically, a record can be fragmented,
* and non-terminal fragments will not have the top
* bit set in the fragment length header.
* But apparently no known nfs clients send fragmented
* records. */
if (net_ratelimit())
printk(KERN_NOTICE "RPC: multiple fragments "
"per record not supported\n");
goto err_delete;
}
svsk->sk_reclen &= RPC_FRAGMENT_SIZE_MASK;
dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen);
if (svsk->sk_reclen > serv->sv_max_mesg) {
if (net_ratelimit())
printk(KERN_NOTICE "RPC: "
"fragment too large: 0x%08lx\n",
(unsigned long)svsk->sk_reclen);
goto err_delete;
}
}
/* Check whether enough data is available */
len = svc_recv_available(svsk);
if (len < 0)
goto error;
if (len < svsk->sk_reclen) {
dprintk("svc: incomplete TCP record (%d of %d)\n",
len, svsk->sk_reclen);
svc_xprt_received(&svsk->sk_xprt);
return -EAGAIN; /* record not complete */
}
len = svsk->sk_reclen;
set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
vec = rqstp->rq_vec;
vec[0] = rqstp->rq_arg.head[0];
vlen = PAGE_SIZE;
pnum = 1;
while (vlen < len) {
vec[pnum].iov_base = page_address(rqstp->rq_pages[pnum]);
vec[pnum].iov_len = PAGE_SIZE;
pnum++;
vlen += PAGE_SIZE;
}
rqstp->rq_respages = &rqstp->rq_pages[pnum];
/* Now receive data */
len = svc_recvfrom(rqstp, vec, pnum, len);
if (len < 0)
goto error;
dprintk("svc: TCP complete record (%d bytes)\n", len);
rqstp->rq_arg.len = len;
rqstp->rq_arg.page_base = 0;
if (len <= rqstp->rq_arg.head[0].iov_len) {
rqstp->rq_arg.head[0].iov_len = len;
rqstp->rq_arg.page_len = 0;
} else {
rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
}
rqstp->rq_xprt_ctxt = NULL;
rqstp->rq_prot = IPPROTO_TCP;
/* Reset TCP read info */
svsk->sk_reclen = 0;
svsk->sk_tcplen = 0;
svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt);
svc_xprt_received(&svsk->sk_xprt);
if (serv->sv_stats)
serv->sv_stats->nettcpcnt++;
return len;
err_delete:
set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
return -EAGAIN;
error:
if (len == -EAGAIN) {
dprintk("RPC: TCP recvfrom got EAGAIN\n");
svc_xprt_received(&svsk->sk_xprt);
} else {
printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
svsk->sk_xprt.xpt_server->sv_name, -len);
goto err_delete;
}
return len;
}
/*
* Send out data on TCP socket.
*/
static int svc_tcp_sendto(struct svc_rqst *rqstp)
{
struct xdr_buf *xbufp = &rqstp->rq_res;
int sent;
__be32 reclen;
/* Set up the first element of the reply kvec.
* Any other kvecs that may be in use have been taken
* care of by the server implementation itself.
*/
reclen = htonl(0x80000000|((xbufp->len ) - 4));
memcpy(xbufp->head[0].iov_base, &reclen, 4);
if (test_bit(XPT_DEAD, &rqstp->rq_xprt->xpt_flags))
return -ENOTCONN;
sent = svc_sendto(rqstp, &rqstp->rq_res);
if (sent != xbufp->len) {
printk(KERN_NOTICE
"rpc-srv/tcp: %s: %s %d when sending %d bytes "
"- shutting down socket\n",
rqstp->rq_xprt->xpt_server->sv_name,
(sent<0)?"got error":"sent only",
sent, xbufp->len);
set_bit(XPT_CLOSE, &rqstp->rq_xprt->xpt_flags);
svc_xprt_enqueue(rqstp->rq_xprt);
sent = -EAGAIN;
}
return sent;
}
/*
* Setup response header. TCP has a 4B record length field.
*/
static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp)
{
struct kvec *resv = &rqstp->rq_res.head[0];
/* tcp needs a space for the record length... */
svc_putnl(resv, 0);
}
static int svc_tcp_has_wspace(struct svc_xprt *xprt)
{
struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
struct svc_serv *serv = svsk->sk_xprt.xpt_server;
int required;
int wspace;
/*
* Set the SOCK_NOSPACE flag before checking the available
* sock space.
*/
set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
wspace = sk_stream_wspace(svsk->sk_sk);
if (wspace < sk_stream_min_wspace(svsk->sk_sk))
return 0;
if (required * 2 > wspace)
return 0;
clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
return 1;
}
static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
struct sockaddr *sa, int salen,
int flags)
{
return svc_create_socket(serv, IPPROTO_TCP, sa, salen, flags);
}
static struct svc_xprt_ops svc_tcp_ops = {
.xpo_create = svc_tcp_create,
.xpo_recvfrom = svc_tcp_recvfrom,
.xpo_sendto = svc_tcp_sendto,
.xpo_release_rqst = svc_release_skb,
.xpo_detach = svc_sock_detach,
.xpo_free = svc_sock_free,
.xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
.xpo_has_wspace = svc_tcp_has_wspace,
.xpo_accept = svc_tcp_accept,
};
static struct svc_xprt_class svc_tcp_class = {
.xcl_name = "tcp",
.xcl_owner = THIS_MODULE,
.xcl_ops = &svc_tcp_ops,
.xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
};
void svc_init_xprt_sock(void)
{
svc_reg_xprt_class(&svc_tcp_class);
svc_reg_xprt_class(&svc_udp_class);
}
void svc_cleanup_xprt_sock(void)
{
svc_unreg_xprt_class(&svc_tcp_class);
svc_unreg_xprt_class(&svc_udp_class);
}
static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
{
struct sock *sk = svsk->sk_sk;
svc_xprt_init(&svc_tcp_class, &svsk->sk_xprt, serv);
set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
if (sk->sk_state == TCP_LISTEN) {
dprintk("setting up TCP socket for listening\n");
set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
sk->sk_data_ready = svc_tcp_listen_data_ready;
set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
} else {
dprintk("setting up TCP socket for reading\n");
sk->sk_state_change = svc_tcp_state_change;
sk->sk_data_ready = svc_tcp_data_ready;
sk->sk_write_space = svc_write_space;
svsk->sk_reclen = 0;
svsk->sk_tcplen = 0;
tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
/* initialise setting must have enough space to
* receive and respond to one request.
* svc_tcp_recvfrom will re-adjust if necessary
*/
svc_sock_setbufsize(svsk->sk_sock,
3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
if (sk->sk_state != TCP_ESTABLISHED)
set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
}
}
void svc_sock_update_bufs(struct svc_serv *serv)
{
/*
* The number of server threads has changed. Update
* rcvbuf and sndbuf accordingly on all sockets
*/
struct list_head *le;
spin_lock_bh(&serv->sv_lock);
list_for_each(le, &serv->sv_permsocks) {
struct svc_sock *svsk =
list_entry(le, struct svc_sock, sk_xprt.xpt_list);
set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
}
list_for_each(le, &serv->sv_tempsocks) {
struct svc_sock *svsk =
list_entry(le, struct svc_sock, sk_xprt.xpt_list);
set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
}
spin_unlock_bh(&serv->sv_lock);
}
EXPORT_SYMBOL(svc_sock_update_bufs);
/*
* Initialize socket for RPC use and create svc_sock struct
* XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF.
*/
static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
struct socket *sock,
int *errp, int flags)
{
struct svc_sock *svsk;
struct sock *inet;
int pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
dprintk("svc: svc_setup_socket %p\n", sock);
if (!(svsk = kzalloc(sizeof(*svsk), GFP_KERNEL))) {
*errp = -ENOMEM;
return NULL;
}
inet = sock->sk;
/* Register socket with portmapper */
if (*errp >= 0 && pmap_register)
*errp = svc_register(serv, inet->sk_protocol,
ntohs(inet_sk(inet)->sport));
if (*errp < 0) {
kfree(svsk);
return NULL;
}
inet->sk_user_data = svsk;
svsk->sk_sock = sock;
svsk->sk_sk = inet;
svsk->sk_ostate = inet->sk_state_change;
svsk->sk_odata = inet->sk_data_ready;
svsk->sk_owspace = inet->sk_write_space;
/* Initialize the socket */
if (sock->type == SOCK_DGRAM)
svc_udp_init(svsk, serv);
else
svc_tcp_init(svsk, serv);
dprintk("svc: svc_setup_socket created %p (inet %p)\n",
svsk, svsk->sk_sk);
return svsk;
}
int svc_addsock(struct svc_serv *serv,
int fd,
char *name_return,
int *proto)
{
int err = 0;
struct socket *so = sockfd_lookup(fd, &err);
struct svc_sock *svsk = NULL;
if (!so)
return err;
if (so->sk->sk_family != AF_INET)
err = -EAFNOSUPPORT;
else if (so->sk->sk_protocol != IPPROTO_TCP &&
so->sk->sk_protocol != IPPROTO_UDP)
err = -EPROTONOSUPPORT;
else if (so->state > SS_UNCONNECTED)
err = -EISCONN;
else {
svsk = svc_setup_socket(serv, so, &err, SVC_SOCK_DEFAULTS);
if (svsk) {
struct sockaddr_storage addr;
struct sockaddr *sin = (struct sockaddr *)&addr;
int salen;
if (kernel_getsockname(svsk->sk_sock, sin, &salen) == 0)
svc_xprt_set_local(&svsk->sk_xprt, sin, salen);
clear_bit(XPT_TEMP, &svsk->sk_xprt.xpt_flags);
spin_lock_bh(&serv->sv_lock);
list_add(&svsk->sk_xprt.xpt_list, &serv->sv_permsocks);
spin_unlock_bh(&serv->sv_lock);
svc_xprt_received(&svsk->sk_xprt);
err = 0;
}
}
if (err) {
sockfd_put(so);
return err;
}
if (proto) *proto = so->sk->sk_protocol;
return one_sock_name(name_return, svsk);
}
EXPORT_SYMBOL_GPL(svc_addsock);
/*
* Create socket for RPC service.
*/
static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
int protocol,
struct sockaddr *sin, int len,
int flags)
{
struct svc_sock *svsk;
struct socket *sock;
int error;
int type;
struct sockaddr_storage addr;
struct sockaddr *newsin = (struct sockaddr *)&addr;
int newlen;
RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
dprintk("svc: svc_create_socket(%s, %d, %s)\n",
serv->sv_program->pg_name, protocol,
__svc_print_addr(sin, buf, sizeof(buf)));
if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
printk(KERN_WARNING "svc: only UDP and TCP "
"sockets supported\n");
return ERR_PTR(-EINVAL);
}
type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
error = sock_create_kern(sin->sa_family, type, protocol, &sock);
if (error < 0)
return ERR_PTR(error);
svc_reclassify_socket(sock);
if (type == SOCK_STREAM)
sock->sk->sk_reuse = 1; /* allow address reuse */
error = kernel_bind(sock, sin, len);
if (error < 0)
goto bummer;
newlen = len;
error = kernel_getsockname(sock, newsin, &newlen);
if (error < 0)
goto bummer;
if (protocol == IPPROTO_TCP) {
if ((error = kernel_listen(sock, 64)) < 0)
goto bummer;
}
if ((svsk = svc_setup_socket(serv, sock, &error, flags)) != NULL) {
svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
return (struct svc_xprt *)svsk;
}
bummer:
dprintk("svc: svc_create_socket error = %d\n", -error);
sock_release(sock);
return ERR_PTR(error);
}
/*
* Detach the svc_sock from the socket so that no
* more callbacks occur.
*/
static void svc_sock_detach(struct svc_xprt *xprt)
{
struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
struct sock *sk = svsk->sk_sk;
dprintk("svc: svc_sock_detach(%p)\n", svsk);
/* put back the old socket callbacks */
sk->sk_state_change = svsk->sk_ostate;
sk->sk_data_ready = svsk->sk_odata;
sk->sk_write_space = svsk->sk_owspace;
}
/*
* Free the svc_sock's socket resources and the svc_sock itself.
*/
static void svc_sock_free(struct svc_xprt *xprt)
{
struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
dprintk("svc: svc_sock_free(%p)\n", svsk);
if (svsk->sk_sock->file)
sockfd_put(svsk->sk_sock);
else
sock_release(svsk->sk_sock);
kfree(svsk);
}