blob: 0e1691316f4234ef859bd179d56c90469faa7033 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* linux/net/sunrpc/xprtsock.c
*
* Client-side transport implementation for sockets.
*
* TCP callback races fixes (C) 1998 Red Hat
* TCP send fixes (C) 1998 Red Hat
* 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/string.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/un.h>
#include <linux/udp.h>
#include <linux/tcp.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/addr.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/xprtsock.h>
#include <linux/file.h>
#ifdef CONFIG_SUNRPC_BACKCHANNEL
#include <linux/sunrpc/bc_xprt.h>
#endif
#include <net/sock.h>
#include <net/checksum.h>
#include <net/udp.h>
#include <net/tcp.h>
#include <net/tls_prot.h>
#include <net/handshake.h>
#include <linux/bvec.h>
#include <linux/highmem.h>
#include <linux/uio.h>
#include <linux/sched/mm.h>
#include <trace/events/sock.h>
#include <trace/events/sunrpc.h>
#include "socklib.h"
#include "sunrpc.h"
static void xs_close(struct rpc_xprt *xprt);
static void xs_reset_srcport(struct sock_xprt *transport);
static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock);
static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
struct socket *sock);
/*
* xprtsock tunables
*/
static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
#define XS_TCP_LINGER_TO (15U * HZ)
static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
/*
* We can register our own files under /proc/sys/sunrpc by
* calling register_sysctl() 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!
*/
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 max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
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;
static struct xprt_class xs_local_transport;
static struct xprt_class xs_udp_transport;
static struct xprt_class xs_tcp_transport;
static struct xprt_class xs_tcp_tls_transport;
static struct xprt_class xs_bc_tcp_transport;
/*
* FIXME: changing the UDP slot table size should also resize the UDP
* socket buffers for existing UDP transports
*/
static struct ctl_table xs_tunables_table[] = {
{
.procname = "udp_slot_table_entries",
.data = &xprt_udp_slot_table_entries,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &min_slot_table_size,
.extra2 = &max_slot_table_size
},
{
.procname = "tcp_slot_table_entries",
.data = &xprt_tcp_slot_table_entries,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &min_slot_table_size,
.extra2 = &max_slot_table_size
},
{
.procname = "tcp_max_slot_table_entries",
.data = &xprt_max_tcp_slot_table_entries,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &min_slot_table_size,
.extra2 = &max_tcp_slot_table_limit
},
{
.procname = "min_resvport",
.data = &xprt_min_resvport,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &xprt_min_resvport_limit,
.extra2 = &xprt_max_resvport_limit
},
{
.procname = "max_resvport",
.data = &xprt_max_resvport,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &xprt_min_resvport_limit,
.extra2 = &xprt_max_resvport_limit
},
{
.procname = "tcp_fin_timeout",
.data = &xs_tcp_fin_timeout,
.maxlen = sizeof(xs_tcp_fin_timeout),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
};
/*
* 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)
/*
* 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)
/*
* TLS handshake timeout.
*/
#define XS_TLS_HANDSHAKE_TO (10U * HZ)
#if IS_ENABLED(CONFIG_SUNRPC_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
static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
{
return (struct rpc_xprt *) sk->sk_user_data;
}
static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
{
return (struct sockaddr *) &xprt->addr;
}
static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
{
return (struct sockaddr_un *) &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_common_peer_addresses(struct rpc_xprt *xprt)
{
struct sockaddr *sap = xs_addr(xprt);
struct sockaddr_in6 *sin6;
struct sockaddr_in *sin;
struct sockaddr_un *sun;
char buf[128];
switch (sap->sa_family) {
case AF_LOCAL:
sun = xs_addr_un(xprt);
if (sun->sun_path[0]) {
strscpy(buf, sun->sun_path, sizeof(buf));
} else {
buf[0] = '@';
strscpy(buf+1, sun->sun_path+1, sizeof(buf)-1);
}
xprt->address_strings[RPC_DISPLAY_ADDR] =
kstrdup(buf, GFP_KERNEL);
break;
case AF_INET:
(void)rpc_ntop(sap, buf, sizeof(buf));
xprt->address_strings[RPC_DISPLAY_ADDR] =
kstrdup(buf, GFP_KERNEL);
sin = xs_addr_in(xprt);
snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
break;
case AF_INET6:
(void)rpc_ntop(sap, buf, sizeof(buf));
xprt->address_strings[RPC_DISPLAY_ADDR] =
kstrdup(buf, GFP_KERNEL);
sin6 = xs_addr_in6(xprt);
snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
break;
default:
BUG();
}
xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
}
static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
{
struct sockaddr *sap = xs_addr(xprt);
char buf[128];
snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
}
static void xs_format_peer_addresses(struct rpc_xprt *xprt,
const char *protocol,
const char *netid)
{
xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
xprt->address_strings[RPC_DISPLAY_NETID] = netid;
xs_format_common_peer_addresses(xprt);
xs_format_common_peer_ports(xprt);
}
static void xs_update_peer_port(struct rpc_xprt *xprt)
{
kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
xs_format_common_peer_ports(xprt);
}
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]);
}
}
static size_t
xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
{
size_t i,n;
if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
return want;
n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
for (i = 0; i < n; i++) {
if (buf->pages[i])
continue;
buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
if (!buf->pages[i]) {
i *= PAGE_SIZE;
return i > buf->page_base ? i - buf->page_base : 0;
}
}
return want;
}
static int
xs_sock_process_cmsg(struct socket *sock, struct msghdr *msg,
struct cmsghdr *cmsg, int ret)
{
u8 content_type = tls_get_record_type(sock->sk, cmsg);
u8 level, description;
switch (content_type) {
case 0:
break;
case TLS_RECORD_TYPE_DATA:
/* TLS sets EOR at the end of each application data
* record, even though there might be more frames
* waiting to be decrypted.
*/
msg->msg_flags &= ~MSG_EOR;
break;
case TLS_RECORD_TYPE_ALERT:
tls_alert_recv(sock->sk, msg, &level, &description);
ret = (level == TLS_ALERT_LEVEL_FATAL) ?
-EACCES : -EAGAIN;
break;
default:
/* discard this record type */
ret = -EAGAIN;
}
return ret;
}
static int
xs_sock_recv_cmsg(struct socket *sock, struct msghdr *msg, int flags)
{
union {
struct cmsghdr cmsg;
u8 buf[CMSG_SPACE(sizeof(u8))];
} u;
int ret;
msg->msg_control = &u;
msg->msg_controllen = sizeof(u);
ret = sock_recvmsg(sock, msg, flags);
if (msg->msg_controllen != sizeof(u))
ret = xs_sock_process_cmsg(sock, msg, &u.cmsg, ret);
return ret;
}
static ssize_t
xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
{
ssize_t ret;
if (seek != 0)
iov_iter_advance(&msg->msg_iter, seek);
ret = xs_sock_recv_cmsg(sock, msg, flags);
return ret > 0 ? ret + seek : ret;
}
static ssize_t
xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
struct kvec *kvec, size_t count, size_t seek)
{
iov_iter_kvec(&msg->msg_iter, ITER_DEST, kvec, 1, count);
return xs_sock_recvmsg(sock, msg, flags, seek);
}
static ssize_t
xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
struct bio_vec *bvec, unsigned long nr, size_t count,
size_t seek)
{
iov_iter_bvec(&msg->msg_iter, ITER_DEST, bvec, nr, count);
return xs_sock_recvmsg(sock, msg, flags, seek);
}
static ssize_t
xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
size_t count)
{
iov_iter_discard(&msg->msg_iter, ITER_DEST, count);
return xs_sock_recv_cmsg(sock, msg, flags);
}
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
static void
xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
{
struct bvec_iter bi = {
.bi_size = count,
};
struct bio_vec bv;
bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
for_each_bvec(bv, bvec, bi, bi)
flush_dcache_page(bv.bv_page);
}
#else
static inline void
xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
{
}
#endif
static ssize_t
xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
{
size_t want, seek_init = seek, offset = 0;
ssize_t ret;
want = min_t(size_t, count, buf->head[0].iov_len);
if (seek < want) {
ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
if (ret <= 0)
goto sock_err;
offset += ret;
if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
goto out;
if (ret != want)
goto out;
seek = 0;
} else {
seek -= want;
offset += want;
}
want = xs_alloc_sparse_pages(
buf, min_t(size_t, count - offset, buf->page_len),
GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
if (seek < want) {
ret = xs_read_bvec(sock, msg, flags, buf->bvec,
xdr_buf_pagecount(buf),
want + buf->page_base,
seek + buf->page_base);
if (ret <= 0)
goto sock_err;
xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
ret -= buf->page_base;
offset += ret;
if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
goto out;
if (ret != want)
goto out;
seek = 0;
} else {
seek -= want;
offset += want;
}
want = min_t(size_t, count - offset, buf->tail[0].iov_len);
if (seek < want) {
ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
if (ret <= 0)
goto sock_err;
offset += ret;
if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
goto out;
if (ret != want)
goto out;
} else if (offset < seek_init)
offset = seek_init;
ret = -EMSGSIZE;
out:
*read = offset - seek_init;
return ret;
sock_err:
offset += seek;
goto out;
}
static void
xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
{
if (!transport->recv.copied) {
if (buf->head[0].iov_len >= transport->recv.offset)
memcpy(buf->head[0].iov_base,
&transport->recv.xid,
transport->recv.offset);
transport->recv.copied = transport->recv.offset;
}
}
static bool
xs_read_stream_request_done(struct sock_xprt *transport)
{
return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
}
static void
xs_read_stream_check_eor(struct sock_xprt *transport,
struct msghdr *msg)
{
if (xs_read_stream_request_done(transport))
msg->msg_flags |= MSG_EOR;
}
static ssize_t
xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
int flags, struct rpc_rqst *req)
{
struct xdr_buf *buf = &req->rq_private_buf;
size_t want, read;
ssize_t ret;
xs_read_header(transport, buf);
want = transport->recv.len - transport->recv.offset;
if (want != 0) {
ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
transport->recv.copied + want,
transport->recv.copied,
&read);
transport->recv.offset += read;
transport->recv.copied += read;
}
if (transport->recv.offset == transport->recv.len)
xs_read_stream_check_eor(transport, msg);
if (want == 0)
return 0;
switch (ret) {
default:
break;
case -EFAULT:
case -EMSGSIZE:
msg->msg_flags |= MSG_TRUNC;
return read;
case 0:
return -ESHUTDOWN;
}
return ret < 0 ? ret : read;
}
static size_t
xs_read_stream_headersize(bool isfrag)
{
if (isfrag)
return sizeof(__be32);
return 3 * sizeof(__be32);
}
static ssize_t
xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
int flags, size_t want, size_t seek)
{
struct kvec kvec = {
.iov_base = &transport->recv.fraghdr,
.iov_len = want,
};
return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
}
#if defined(CONFIG_SUNRPC_BACKCHANNEL)
static ssize_t
xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
{
struct rpc_xprt *xprt = &transport->xprt;
struct rpc_rqst *req;
ssize_t ret;
/* Is this transport associated with the backchannel? */
if (!xprt->bc_serv)
return -ESHUTDOWN;
/* Look up and lock the request corresponding to the given XID */
req = xprt_lookup_bc_request(xprt, transport->recv.xid);
if (!req) {
printk(KERN_WARNING "Callback slot table overflowed\n");
return -ESHUTDOWN;
}
if (transport->recv.copied && !req->rq_private_buf.len)
return -ESHUTDOWN;
ret = xs_read_stream_request(transport, msg, flags, req);
if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
xprt_complete_bc_request(req, transport->recv.copied);
else
req->rq_private_buf.len = transport->recv.copied;
return ret;
}
#else /* CONFIG_SUNRPC_BACKCHANNEL */
static ssize_t
xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
{
return -ESHUTDOWN;
}
#endif /* CONFIG_SUNRPC_BACKCHANNEL */
static ssize_t
xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
{
struct rpc_xprt *xprt = &transport->xprt;
struct rpc_rqst *req;
ssize_t ret = 0;
/* Look up and lock the request corresponding to the given XID */
spin_lock(&xprt->queue_lock);
req = xprt_lookup_rqst(xprt, transport->recv.xid);
if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
msg->msg_flags |= MSG_TRUNC;
goto out;
}
xprt_pin_rqst(req);
spin_unlock(&xprt->queue_lock);
ret = xs_read_stream_request(transport, msg, flags, req);
spin_lock(&xprt->queue_lock);
if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
xprt_complete_rqst(req->rq_task, transport->recv.copied);
else
req->rq_private_buf.len = transport->recv.copied;
xprt_unpin_rqst(req);
out:
spin_unlock(&xprt->queue_lock);
return ret;
}
static ssize_t
xs_read_stream(struct sock_xprt *transport, int flags)
{
struct msghdr msg = { 0 };
size_t want, read = 0;
ssize_t ret = 0;
if (transport->recv.len == 0) {
want = xs_read_stream_headersize(transport->recv.copied != 0);
ret = xs_read_stream_header(transport, &msg, flags, want,
transport->recv.offset);
if (ret <= 0)
goto out_err;
transport->recv.offset = ret;
if (transport->recv.offset != want)
return transport->recv.offset;
transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
RPC_FRAGMENT_SIZE_MASK;
transport->recv.offset -= sizeof(transport->recv.fraghdr);
read = ret;
}
switch (be32_to_cpu(transport->recv.calldir)) {
default:
msg.msg_flags |= MSG_TRUNC;
break;
case RPC_CALL:
ret = xs_read_stream_call(transport, &msg, flags);
break;
case RPC_REPLY:
ret = xs_read_stream_reply(transport, &msg, flags);
}
if (msg.msg_flags & MSG_TRUNC) {
transport->recv.calldir = cpu_to_be32(-1);
transport->recv.copied = -1;
}
if (ret < 0)
goto out_err;
read += ret;
if (transport->recv.offset < transport->recv.len) {
if (!(msg.msg_flags & MSG_TRUNC))
return read;
msg.msg_flags = 0;
ret = xs_read_discard(transport->sock, &msg, flags,
transport->recv.len - transport->recv.offset);
if (ret <= 0)
goto out_err;
transport->recv.offset += ret;
read += ret;
if (transport->recv.offset != transport->recv.len)
return read;
}
if (xs_read_stream_request_done(transport)) {
trace_xs_stream_read_request(transport);
transport->recv.copied = 0;
}
transport->recv.offset = 0;
transport->recv.len = 0;
return read;
out_err:
return ret != 0 ? ret : -ESHUTDOWN;
}
static __poll_t xs_poll_socket(struct sock_xprt *transport)
{
return transport->sock->ops->poll(transport->file, transport->sock,
NULL);
}
static bool xs_poll_socket_readable(struct sock_xprt *transport)
{
__poll_t events = xs_poll_socket(transport);
return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
}
static void xs_poll_check_readable(struct sock_xprt *transport)
{
clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
if (test_bit(XPRT_SOCK_IGNORE_RECV, &transport->sock_state))
return;
if (!xs_poll_socket_readable(transport))
return;
if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
queue_work(xprtiod_workqueue, &transport->recv_worker);
}
static void xs_stream_data_receive(struct sock_xprt *transport)
{
size_t read = 0;
ssize_t ret = 0;
mutex_lock(&transport->recv_mutex);
if (transport->sock == NULL)
goto out;
for (;;) {
ret = xs_read_stream(transport, MSG_DONTWAIT);
if (ret < 0)
break;
read += ret;
cond_resched();
}
if (ret == -ESHUTDOWN)
kernel_sock_shutdown(transport->sock, SHUT_RDWR);
else if (ret == -EACCES)
xprt_wake_pending_tasks(&transport->xprt, -EACCES);
else
xs_poll_check_readable(transport);
out:
mutex_unlock(&transport->recv_mutex);
trace_xs_stream_read_data(&transport->xprt, ret, read);
}
static void xs_stream_data_receive_workfn(struct work_struct *work)
{
struct sock_xprt *transport =
container_of(work, struct sock_xprt, recv_worker);
unsigned int pflags = memalloc_nofs_save();
xs_stream_data_receive(transport);
memalloc_nofs_restore(pflags);
}
static void
xs_stream_reset_connect(struct sock_xprt *transport)
{
transport->recv.offset = 0;
transport->recv.len = 0;
transport->recv.copied = 0;
transport->xmit.offset = 0;
}
static void
xs_stream_start_connect(struct sock_xprt *transport)
{
transport->xprt.stat.connect_count++;
transport->xprt.stat.connect_start = jiffies;
}
#define XS_SENDMSG_FLAGS (MSG_DONTWAIT | MSG_NOSIGNAL)
/**
* xs_nospace - handle transmit was incomplete
* @req: pointer to RPC request
* @transport: pointer to struct sock_xprt
*
*/
static int xs_nospace(struct rpc_rqst *req, struct sock_xprt *transport)
{
struct rpc_xprt *xprt = &transport->xprt;
struct sock *sk = transport->inet;
int ret = -EAGAIN;
trace_rpc_socket_nospace(req, transport);
/* Protect against races with write_space */
spin_lock(&xprt->transport_lock);
/* Don't race with disconnect */
if (xprt_connected(xprt)) {
/* wait for more buffer space */
set_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
sk->sk_write_pending++;
xprt_wait_for_buffer_space(xprt);
} else
ret = -ENOTCONN;
spin_unlock(&xprt->transport_lock);
return ret;
}
static int xs_sock_nospace(struct rpc_rqst *req)
{
struct sock_xprt *transport =
container_of(req->rq_xprt, struct sock_xprt, xprt);
struct sock *sk = transport->inet;
int ret = -EAGAIN;
lock_sock(sk);
if (!sock_writeable(sk))
ret = xs_nospace(req, transport);
release_sock(sk);
return ret;
}
static int xs_stream_nospace(struct rpc_rqst *req, bool vm_wait)
{
struct sock_xprt *transport =
container_of(req->rq_xprt, struct sock_xprt, xprt);
struct sock *sk = transport->inet;
int ret = -EAGAIN;
if (vm_wait)
return -ENOBUFS;
lock_sock(sk);
if (!sk_stream_memory_free(sk))
ret = xs_nospace(req, transport);
release_sock(sk);
return ret;
}
static int xs_stream_prepare_request(struct rpc_rqst *req, struct xdr_buf *buf)
{
return xdr_alloc_bvec(buf, rpc_task_gfp_mask());
}
static void xs_stream_abort_send_request(struct rpc_rqst *req)
{
struct rpc_xprt *xprt = req->rq_xprt;
struct sock_xprt *transport =
container_of(xprt, struct sock_xprt, xprt);
if (transport->xmit.offset != 0 &&
!test_bit(XPRT_CLOSE_WAIT, &xprt->state))
xprt_force_disconnect(xprt);
}
/*
* Determine if the previous message in the stream was aborted before it
* could complete transmission.
*/
static bool
xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
{
return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
}
/*
* Return the stream record marker field for a record of length < 2^31-1
*/
static rpc_fraghdr
xs_stream_record_marker(struct xdr_buf *xdr)
{
if (!xdr->len)
return 0;
return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
}
/**
* xs_local_send_request - write an RPC request to an AF_LOCAL socket
* @req: pointer to 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 occurred, the request was not sent
*/
static int xs_local_send_request(struct rpc_rqst *req)
{
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;
rpc_fraghdr rm = xs_stream_record_marker(xdr);
unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
struct msghdr msg = {
.msg_flags = XS_SENDMSG_FLAGS,
};
bool vm_wait;
unsigned int sent;
int status;
/* Close the stream if the previous transmission was incomplete */
if (xs_send_request_was_aborted(transport, req)) {
xprt_force_disconnect(xprt);
return -ENOTCONN;
}
xs_pktdump("packet data:",
req->rq_svec->iov_base, req->rq_svec->iov_len);
vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
req->rq_xtime = ktime_get();
status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
transport->xmit.offset, rm, &sent);
dprintk("RPC: %s(%u) = %d\n",
__func__, xdr->len - transport->xmit.offset, status);
if (likely(sent > 0) || status == 0) {
transport->xmit.offset += sent;
req->rq_bytes_sent = transport->xmit.offset;
if (likely(req->rq_bytes_sent >= msglen)) {
req->rq_xmit_bytes_sent += transport->xmit.offset;
transport->xmit.offset = 0;
return 0;
}
status = -EAGAIN;
vm_wait = false;
}
switch (status) {
case -EAGAIN:
status = xs_stream_nospace(req, vm_wait);
break;
default:
dprintk("RPC: sendmsg returned unrecognized error %d\n",
-status);
fallthrough;
case -EPIPE:
xprt_force_disconnect(xprt);
status = -ENOTCONN;
}
return status;
}
/**
* xs_udp_send_request - write an RPC request to a UDP socket
* @req: pointer to 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 occurred, the request was not sent
*/
static int xs_udp_send_request(struct rpc_rqst *req)
{
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;
struct msghdr msg = {
.msg_name = xs_addr(xprt),
.msg_namelen = xprt->addrlen,
.msg_flags = XS_SENDMSG_FLAGS,
};
unsigned int sent;
int status;
xs_pktdump("packet data:",
req->rq_svec->iov_base,
req->rq_svec->iov_len);
if (!xprt_bound(xprt))
return -ENOTCONN;
if (!xprt_request_get_cong(xprt, req))
return -EBADSLT;
status = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
if (status < 0)
return status;
req->rq_xtime = ktime_get();
status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
dprintk("RPC: xs_udp_send_request(%u) = %d\n",
xdr->len, status);
/* firewall is blocking us, don't return -EAGAIN or we end up looping */
if (status == -EPERM)
goto process_status;
if (status == -EAGAIN && sock_writeable(transport->inet))
status = -ENOBUFS;
if (sent > 0 || status == 0) {
req->rq_xmit_bytes_sent += sent;
if (sent >= req->rq_slen)
return 0;
/* Still some bytes left; set up for a retry later. */
status = -EAGAIN;
}
process_status:
switch (status) {
case -ENOTSOCK:
status = -ENOTCONN;
/* Should we call xs_close() here? */
break;
case -EAGAIN:
status = xs_sock_nospace(req);
break;
case -ENETUNREACH:
case -ENOBUFS:
case -EPIPE:
case -ECONNREFUSED:
case -EPERM:
/* When the server has died, an ICMP port unreachable message
* prompts ECONNREFUSED. */
break;
default:
dprintk("RPC: sendmsg returned unrecognized error %d\n",
-status);
}
return status;
}
/**
* xs_tcp_send_request - write an RPC request to a TCP socket
* @req: pointer to 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 occurred, 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_rqst *req)
{
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;
rpc_fraghdr rm = xs_stream_record_marker(xdr);
unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
struct msghdr msg = {
.msg_flags = XS_SENDMSG_FLAGS,
};
bool vm_wait;
unsigned int sent;
int status;
/* Close the stream if the previous transmission was incomplete */
if (xs_send_request_was_aborted(transport, req)) {
if (transport->sock != NULL)
kernel_sock_shutdown(transport->sock, SHUT_RDWR);
return -ENOTCONN;
}
if (!transport->inet)
return -ENOTCONN;
xs_pktdump("packet data:",
req->rq_svec->iov_base,
req->rq_svec->iov_len);
if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
xs_tcp_set_socket_timeouts(xprt, transport->sock);
xs_set_srcport(transport, transport->sock);
/* Continue transmitting the packet/record. We must be careful
* to cope with writespace callbacks arriving _after_ we have
* called sendmsg(). */
req->rq_xtime = ktime_get();
tcp_sock_set_cork(transport->inet, true);
vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
do {
status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
transport->xmit.offset, rm, &sent);
dprintk("RPC: xs_tcp_send_request(%u) = %d\n",
xdr->len - transport->xmit.offset, status);
/* If we've sent the entire packet, immediately
* reset the count of bytes sent. */
transport->xmit.offset += sent;
req->rq_bytes_sent = transport->xmit.offset;
if (likely(req->rq_bytes_sent >= msglen)) {
req->rq_xmit_bytes_sent += transport->xmit.offset;
transport->xmit.offset = 0;
if (atomic_long_read(&xprt->xmit_queuelen) == 1)
tcp_sock_set_cork(transport->inet, false);
return 0;
}
WARN_ON_ONCE(sent == 0 && status == 0);
if (sent > 0)
vm_wait = false;
} while (status == 0);
switch (status) {
case -ENOTSOCK:
status = -ENOTCONN;
/* Should we call xs_close() here? */
break;
case -EAGAIN:
status = xs_stream_nospace(req, vm_wait);
break;
case -ECONNRESET:
case -ECONNREFUSED:
case -ENOTCONN:
case -EADDRINUSE:
case -ENOBUFS:
case -EPIPE:
break;
default:
dprintk("RPC: sendmsg returned unrecognized error %d\n",
-status);
}
return status;
}
static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
{
transport->old_data_ready = sk->sk_data_ready;
transport->old_state_change = sk->sk_state_change;
transport->old_write_space = sk->sk_write_space;
transport->old_error_report = sk->sk_error_report;
}
static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
{
sk->sk_data_ready = transport->old_data_ready;
sk->sk_state_change = transport->old_state_change;
sk->sk_write_space = transport->old_write_space;
sk->sk_error_report = transport->old_error_report;
}
static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
transport->xprt_err = 0;
clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
}
static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
{
set_bit(nr, &transport->sock_state);
queue_work(xprtiod_workqueue, &transport->error_worker);
}
static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
{
xprt->connect_cookie++;
smp_mb__before_atomic();
clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
clear_bit(XPRT_CLOSING, &xprt->state);
xs_sock_reset_state_flags(xprt);
smp_mb__after_atomic();
}
/**
* xs_error_report - callback to handle TCP socket state errors
* @sk: socket
*
* Note: we don't call sock_error() since there may be a rpc_task
* using the socket, and so we don't want to clear sk->sk_err.
*/
static void xs_error_report(struct sock *sk)
{
struct sock_xprt *transport;
struct rpc_xprt *xprt;
if (!(xprt = xprt_from_sock(sk)))
return;
transport = container_of(xprt, struct sock_xprt, xprt);
transport->xprt_err = -sk->sk_err;
if (transport->xprt_err == 0)
return;
dprintk("RPC: xs_error_report client %p, error=%d...\n",
xprt, -transport->xprt_err);
trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
smp_mb__before_atomic();
xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
}
static void xs_reset_transport(struct sock_xprt *transport)
{
struct socket *sock = transport->sock;
struct sock *sk = transport->inet;
struct rpc_xprt *xprt = &transport->xprt;
struct file *filp = transport->file;
if (sk == NULL)
return;
/*
* Make sure we're calling this in a context from which it is safe
* to call __fput_sync(). In practice that means rpciod and the
* system workqueue.
*/
if (!(current->flags & PF_WQ_WORKER)) {
WARN_ON_ONCE(1);
set_bit(XPRT_CLOSE_WAIT, &xprt->state);
return;
}
if (atomic_read(&transport->xprt.swapper))
sk_clear_memalloc(sk);
tls_handshake_cancel(sk);
kernel_sock_shutdown(sock, SHUT_RDWR);
mutex_lock(&transport->recv_mutex);
lock_sock(sk);
transport->inet = NULL;
transport->sock = NULL;
transport->file = NULL;
sk->sk_user_data = NULL;
xs_restore_old_callbacks(transport, sk);
xprt_clear_connected(xprt);
xs_sock_reset_connection_flags(xprt);
/* Reset stream record info */
xs_stream_reset_connect(transport);
release_sock(sk);
mutex_unlock(&transport->recv_mutex);
trace_rpc_socket_close(xprt, sock);
__fput_sync(filp);
xprt_disconnect_done(xprt);
}
/**
* 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.
*
* The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
* xs_reset_transport() zeroing the socket from underneath a writer.
*/
static void xs_close(struct rpc_xprt *xprt)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
dprintk("RPC: xs_close xprt %p\n", xprt);
if (transport->sock)
tls_handshake_close(transport->sock);
xs_reset_transport(transport);
xprt->reestablish_timeout = 0;
}
static void xs_inject_disconnect(struct rpc_xprt *xprt)
{
dprintk("RPC: injecting transport disconnect on xprt=%p\n",
xprt);
xprt_disconnect_done(xprt);
}
static void xs_xprt_free(struct rpc_xprt *xprt)
{
xs_free_peer_addresses(xprt);
xprt_free(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_delayed_work_sync(&transport->connect_worker);
xs_close(xprt);
cancel_work_sync(&transport->recv_worker);
cancel_work_sync(&transport->error_worker);
xs_xprt_free(xprt);
module_put(THIS_MODULE);
}
/**
* xs_udp_data_read_skb - receive callback for UDP sockets
* @xprt: transport
* @sk: socket
* @skb: skbuff
*
*/
static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
struct sock *sk,
struct sk_buff *skb)
{
struct rpc_task *task;
struct rpc_rqst *rovr;
int repsize, copied;
u32 _xid;
__be32 *xp;
repsize = skb->len;
if (repsize < 4) {
dprintk("RPC: impossible RPC reply size %d!\n", repsize);
return;
}
/* Copy the XID from the skb... */
xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
if (xp == NULL)
return;
/* Look up and lock the request corresponding to the given XID */
spin_lock(&xprt->queue_lock);
rovr = xprt_lookup_rqst(xprt, *xp);
if (!rovr)
goto out_unlock;
xprt_pin_rqst(rovr);
xprt_update_rtt(rovr->rq_task);
spin_unlock(&xprt->queue_lock);
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)) {
spin_lock(&xprt->queue_lock);
__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
goto out_unpin;
}
spin_lock(&xprt->transport_lock);
xprt_adjust_cwnd(xprt, task, copied);
spin_unlock(&xprt->transport_lock);
spin_lock(&xprt->queue_lock);
xprt_complete_rqst(task, copied);
__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
out_unpin:
xprt_unpin_rqst(rovr);
out_unlock:
spin_unlock(&xprt->queue_lock);
}
static void xs_udp_data_receive(struct sock_xprt *transport)
{
struct sk_buff *skb;
struct sock *sk;
int err;
mutex_lock(&transport->recv_mutex);
sk = transport->inet;
if (sk == NULL)
goto out;
for (;;) {
skb = skb_recv_udp(sk, MSG_DONTWAIT, &err);
if (skb == NULL)
break;
xs_udp_data_read_skb(&transport->xprt, sk, skb);
consume_skb(skb);
cond_resched();
}
xs_poll_check_readable(transport);
out:
mutex_unlock(&transport->recv_mutex);
}
static void xs_udp_data_receive_workfn(struct work_struct *work)
{
struct sock_xprt *transport =
container_of(work, struct sock_xprt, recv_worker);
unsigned int pflags = memalloc_nofs_save();
xs_udp_data_receive(transport);
memalloc_nofs_restore(pflags);
}
/**
* xs_data_ready - "data ready" callback for sockets
* @sk: socket with data to read
*
*/
static void xs_data_ready(struct sock *sk)
{
struct rpc_xprt *xprt;
trace_sk_data_ready(sk);
xprt = xprt_from_sock(sk);
if (xprt != NULL) {
struct sock_xprt *transport = container_of(xprt,
struct sock_xprt, xprt);
trace_xs_data_ready(xprt);
transport->old_data_ready(sk);
if (test_bit(XPRT_SOCK_IGNORE_RECV, &transport->sock_state))
return;
/* Any data means we had a useful conversation, so
* then we don't need to delay the next reconnect
*/
if (xprt->reestablish_timeout)
xprt->reestablish_timeout = 0;
if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
queue_work(xprtiod_workqueue, &transport->recv_worker);
}
}
/*
* Helper function to force a TCP close if the server is sending
* junk and/or it has put us in CLOSE_WAIT
*/
static void xs_tcp_force_close(struct rpc_xprt *xprt)
{
xprt_force_disconnect(xprt);
}
#if defined(CONFIG_SUNRPC_BACKCHANNEL)
static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
{
return PAGE_SIZE;
}
#endif /* CONFIG_SUNRPC_BACKCHANNEL */
/**
* xs_local_state_change - callback to handle AF_LOCAL socket state changes
* @sk: socket whose state has changed
*
*/
static void xs_local_state_change(struct sock *sk)
{
struct rpc_xprt *xprt;
struct sock_xprt *transport;
if (!(xprt = xprt_from_sock(sk)))
return;
transport = container_of(xprt, struct sock_xprt, xprt);
if (sk->sk_shutdown & SHUTDOWN_MASK) {
clear_bit(XPRT_CONNECTED, &xprt->state);
/* Trigger the socket release */
xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
}
}
/**
* 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;
struct sock_xprt *transport;
if (!(xprt = xprt_from_sock(sk)))
return;
dprintk("RPC: xs_tcp_state_change client %p...\n", xprt);
dprintk("RPC: state %x conn %d dead %d zapped %d sk_shutdown %d\n",
sk->sk_state, xprt_connected(xprt),
sock_flag(sk, SOCK_DEAD),
sock_flag(sk, SOCK_ZAPPED),
sk->sk_shutdown);
transport = container_of(xprt, struct sock_xprt, xprt);
trace_rpc_socket_state_change(xprt, sk->sk_socket);
switch (sk->sk_state) {
case TCP_ESTABLISHED:
if (!xprt_test_and_set_connected(xprt)) {
xprt->connect_cookie++;
clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
xprt_clear_connecting(xprt);
xprt->stat.connect_count++;
xprt->stat.connect_time += (long)jiffies -
xprt->stat.connect_start;
xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
}
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_atomic();
clear_bit(XPRT_CONNECTED, &xprt->state);
clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
smp_mb__after_atomic();
break;
case TCP_CLOSE_WAIT:
/* The server initiated a shutdown of the socket */
xprt->connect_cookie++;
clear_bit(XPRT_CONNECTED, &xprt->state);
xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
fallthrough;
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:
set_bit(XPRT_CLOSING, &xprt->state);
smp_mb__before_atomic();
clear_bit(XPRT_CONNECTED, &xprt->state);
smp_mb__after_atomic();
break;
case TCP_CLOSE:
if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
&transport->sock_state)) {
xs_reset_srcport(transport);
xprt_clear_connecting(xprt);
}
clear_bit(XPRT_CLOSING, &xprt->state);
/* Trigger the socket release */
xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
}
}
static void xs_write_space(struct sock *sk)
{
struct sock_xprt *transport;
struct rpc_xprt *xprt;
if (!sk->sk_socket)
return;
clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
if (unlikely(!(xprt = xprt_from_sock(sk))))
return;
transport = container_of(xprt, struct sock_xprt, xprt);
if (!test_and_clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state))
return;
xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
sk->sk_write_pending--;
}
/**
* 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)
{
/* from net/core/sock.c:sock_def_write_space */
if (sock_writeable(sk))
xs_write_space(sk);
}
/**
* 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)
{
/* from net/core/stream.c:sk_stream_write_space */
if (sk_stream_is_writeable(sk))
xs_write_space(sk);
}
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
* @xprt: controlling transport
* @task: task that timed out
*
* Adjust the congestion window after a retransmit timeout has occurred.
*/
static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
{
spin_lock(&xprt->transport_lock);
xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
spin_unlock(&xprt->transport_lock);
}
static int xs_get_random_port(void)
{
unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
unsigned short range;
unsigned short rand;
if (max < min)
return -EADDRINUSE;
range = max - min + 1;
rand = get_random_u32_below(range);
return rand + min;
}
static unsigned short xs_sock_getport(struct socket *sock)
{
struct sockaddr_storage buf;
unsigned short port = 0;
if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
goto out;
switch (buf.ss_family) {
case AF_INET6:
port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
break;
case AF_INET:
port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
}
out:
return port;
}
/**
* 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)
{
dprintk("RPC: setting port for xprt %p to %u\n", xprt, port);
rpc_set_port(xs_addr(xprt), port);
xs_update_peer_port(xprt);
}
static void xs_reset_srcport(struct sock_xprt *transport)
{
transport->srcport = 0;
}
static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
{
if (transport->srcport == 0 && transport->xprt.reuseport)
transport->srcport = xs_sock_getport(sock);
}
static int xs_get_srcport(struct sock_xprt *transport)
{
int port = transport->srcport;
if (port == 0 && transport->xprt.resvport)
port = xs_get_random_port();
return port;
}
static unsigned short xs_sock_srcport(struct rpc_xprt *xprt)
{
struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
unsigned short ret = 0;
mutex_lock(&sock->recv_mutex);
if (sock->sock)
ret = xs_sock_getport(sock->sock);
mutex_unlock(&sock->recv_mutex);
return ret;
}
static int xs_sock_srcaddr(struct rpc_xprt *xprt, char *buf, size_t buflen)
{
struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
union {
struct sockaddr sa;
struct sockaddr_storage st;
} saddr;
int ret = -ENOTCONN;
mutex_lock(&sock->recv_mutex);
if (sock->sock) {
ret = kernel_getsockname(sock->sock, &saddr.sa);
if (ret >= 0)
ret = snprintf(buf, buflen, "%pISc", &saddr.sa);
}
mutex_unlock(&sock->recv_mutex);
return ret;
}
static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
{
if (transport->srcport != 0)
transport->srcport = 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_bind(struct sock_xprt *transport, struct socket *sock)
{
struct sockaddr_storage myaddr;
int err, nloop = 0;
int port = xs_get_srcport(transport);
unsigned short last;
/*
* If we are asking for any ephemeral port (i.e. port == 0 &&
* transport->xprt.resvport == 0), don't bind. Let the local
* port selection happen implicitly when the socket is used
* (for example at connect time).
*
* This ensures that we can continue to establish TCP
* connections even when all local ephemeral ports are already
* a part of some TCP connection. This makes no difference
* for UDP sockets, but also doesn't harm them.
*
* If we're asking for any reserved port (i.e. port == 0 &&
* transport->xprt.resvport == 1) xs_get_srcport above will
* ensure that port is non-zero and we will bind as needed.
*/
if (port <= 0)
return port;
memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
do {
rpc_set_port((struct sockaddr *)&myaddr, port);
err = kernel_bind(sock, (struct sockaddr *)&myaddr,
transport->xprt.addrlen);
if (err == 0) {
if (transport->xprt.reuseport)
transport->srcport = port;
break;
}
last = port;
port = xs_next_srcport(transport, port);
if (port > last)
nloop++;
} while (err == -EADDRINUSE && nloop != 2);
if (myaddr.ss_family == AF_INET)
dprintk("RPC: %s %pI4:%u: %s (%d)\n", __func__,
&((struct sockaddr_in *)&myaddr)->sin_addr,
port, err ? "failed" : "ok", err);
else
dprintk("RPC: %s %pI6:%u: %s (%d)\n", __func__,
&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
port, err ? "failed" : "ok", err);
return err;
}
/*
* We don't support autobind on AF_LOCAL sockets
*/
static void xs_local_rpcbind(struct rpc_task *task)
{
xprt_set_bound(task->tk_xprt);
}
static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
{
}
#ifdef CONFIG_DEBUG_LOCK_ALLOC
static struct lock_class_key xs_key[3];
static struct lock_class_key xs_slock_key[3];
static inline void xs_reclassify_socketu(struct socket *sock)
{
struct sock *sk = sock->sk;
sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
&xs_slock_key[0], "sk_lock-AF_LOCAL-RPC", &xs_key[0]);
}
static inline void xs_reclassify_socket4(struct socket *sock)
{
struct sock *sk = sock->sk;
sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
&xs_slock_key[1], "sk_lock-AF_INET-RPC", &xs_key[1]);
}
static inline void xs_reclassify_socket6(struct socket *sock)
{
struct sock *sk = sock->sk;
sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
&xs_slock_key[2], "sk_lock-AF_INET6-RPC", &xs_key[2]);
}
static inline void xs_reclassify_socket(int family, struct socket *sock)
{
if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
return;
switch (family) {
case AF_LOCAL:
xs_reclassify_socketu(sock);
break;
case AF_INET:
xs_reclassify_socket4(sock);
break;
case AF_INET6:
xs_reclassify_socket6(sock);
break;
}
}
#else
static inline void xs_reclassify_socket(int family, struct socket *sock)
{
}
#endif
static void xs_dummy_setup_socket(struct work_struct *work)
{
}
static struct socket *xs_create_sock(struct rpc_xprt *xprt,
struct sock_xprt *transport, int family, int type,
int protocol, bool reuseport)
{
struct file *filp;
struct socket *sock;
int err;
err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
if (err < 0) {
dprintk("RPC: can't create %d transport socket (%d).\n",
protocol, -err);
goto out;
}
xs_reclassify_socket(family, sock);
if (reuseport)
sock_set_reuseport(sock->sk);
err = xs_bind(transport, sock);
if (err) {
sock_release(sock);
goto out;
}
filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
if (IS_ERR(filp))
return ERR_CAST(filp);
transport->file = filp;
return sock;
out:
return ERR_PTR(err);
}
static int xs_local_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;
lock_sock(sk);
xs_save_old_callbacks(transport, sk);
sk->sk_user_data = xprt;
sk->sk_data_ready = xs_data_ready;
sk->sk_write_space = xs_udp_write_space;
sk->sk_state_change = xs_local_state_change;
sk->sk_error_report = xs_error_report;
sk->sk_use_task_frag = false;
xprt_clear_connected(xprt);
/* Reset to new socket */
transport->sock = sock;
transport->inet = sk;
release_sock(sk);
}
xs_stream_start_connect(transport);
return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
}
/**
* xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
* @transport: socket transport to connect
*/
static int xs_local_setup_socket(struct sock_xprt *transport)
{
struct rpc_xprt *xprt = &transport->xprt;
struct file *filp;
struct socket *sock;
int status;
status = __sock_create(xprt->xprt_net, AF_LOCAL,
SOCK_STREAM, 0, &sock, 1);
if (status < 0) {
dprintk("RPC: can't create AF_LOCAL "
"transport socket (%d).\n", -status);
goto out;
}
xs_reclassify_socket(AF_LOCAL, sock);
filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
if (IS_ERR(filp)) {
status = PTR_ERR(filp);
goto out;
}
transport->file = filp;
dprintk("RPC: worker connecting xprt %p via AF_LOCAL to %s\n",
xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
status = xs_local_finish_connecting(xprt, sock);
trace_rpc_socket_connect(xprt, sock, status);
switch (status) {
case 0:
dprintk("RPC: xprt %p connected to %s\n",
xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
xprt->stat.connect_count++;
xprt->stat.connect_time += (long)jiffies -
xprt->stat.connect_start;
xprt_set_connected(xprt);
break;
case -ENOBUFS:
break;
case -ENOENT:
dprintk("RPC: xprt %p: socket %s does not exist\n",
xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
break;
case -ECONNREFUSED:
dprintk("RPC: xprt %p: connection refused for %s\n",
xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
break;
default:
printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
__func__, -status,
xprt->address_strings[RPC_DISPLAY_ADDR]);
}
out:
xprt_clear_connecting(xprt);
xprt_wake_pending_tasks(xprt, status);
return status;
}
static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
int ret;
if (transport->file)
goto force_disconnect;
if (RPC_IS_ASYNC(task)) {
/*
* We want the AF_LOCAL connect to be resolved in the
* filesystem namespace of the process making the rpc
* call. Thus we connect synchronously.
*
* If we want to support asynchronous AF_LOCAL calls,
* we'll need to figure out how to pass a namespace to
* connect.
*/
rpc_task_set_rpc_status(task, -ENOTCONN);
goto out_wake;
}
ret = xs_local_setup_socket(transport);
if (ret && !RPC_IS_SOFTCONN(task))
msleep_interruptible(15000);
return;
force_disconnect:
xprt_force_disconnect(xprt);
out_wake:
xprt_clear_connecting(xprt);
xprt_wake_pending_tasks(xprt, -ENOTCONN);
}
#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
/*
* Note that this should be called with XPRT_LOCKED held, or recv_mutex
* held, or when we otherwise know that we have exclusive access to the
* socket, to guard against races with xs_reset_transport.
*/
static void xs_set_memalloc(struct rpc_xprt *xprt)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
xprt);
/*
* If there's no sock, then we have nothing to set. The
* reconnecting process will get it for us.
*/
if (!transport->inet)
return;
if (atomic_read(&xprt->swapper))
sk_set_memalloc(transport->inet);
}
/**
* xs_enable_swap - Tag this transport as being used for swap.
* @xprt: transport to tag
*
* Take a reference to this transport on behalf of the rpc_clnt, and
* optionally mark it for swapping if it wasn't already.
*/
static int
xs_enable_swap(struct rpc_xprt *xprt)
{
struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
mutex_lock(&xs->recv_mutex);
if (atomic_inc_return(&xprt->swapper) == 1 &&
xs->inet)
sk_set_memalloc(xs->inet);
mutex_unlock(&xs->recv_mutex);
return 0;
}
/**
* xs_disable_swap - Untag this transport as being used for swap.
* @xprt: transport to tag
*
* Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
* swapper refcount goes to 0, untag the socket as a memalloc socket.
*/
static void
xs_disable_swap(struct rpc_xprt *xprt)
{
struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
mutex_lock(&xs->recv_mutex);
if (atomic_dec_and_test(&xprt->swapper) &&
xs->inet)
sk_clear_memalloc(xs->inet);
mutex_unlock(&xs->recv_mutex);
}
#else
static void xs_set_memalloc(struct rpc_xprt *xprt)
{
}
static int
xs_enable_swap(struct rpc_xprt *xprt)
{
return -EINVAL;
}
static void
xs_disable_swap(struct rpc_xprt *xprt)
{
}
#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;
lock_sock(sk);
xs_save_old_callbacks(transport, sk);
sk->sk_user_data = xprt;
sk->sk_data_ready = xs_data_ready;
sk->sk_write_space = xs_udp_write_space;
sk->sk_use_task_frag = false;
xprt_set_connected(xprt);
/* Reset to new socket */
transport->sock = sock;
transport->inet = sk;
xs_set_memalloc(xprt);
release_sock(sk);
}
xs_udp_do_set_buffer_size(xprt);
xprt->stat.connect_start = jiffies;
}
static void xs_udp_setup_socket(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;
int status = -EIO;
unsigned int pflags = current->flags;
if (atomic_read(&xprt->swapper))
current->flags |= PF_MEMALLOC;
sock = xs_create_sock(xprt, transport,
xs_addr(xprt)->sa_family, SOCK_DGRAM,
IPPROTO_UDP, false);
if (IS_ERR(sock))
goto out;
dprintk("RPC: worker connecting xprt %p via %s to "
"%s (port %s)\n", xprt,
xprt->address_strings[RPC_DISPLAY_PROTO],
xprt->address_strings[RPC_DISPLAY_ADDR],
xprt->address_strings[RPC_DISPLAY_PORT]);
xs_udp_finish_connecting(xprt, sock);
trace_rpc_socket_connect(xprt, sock, 0);
status = 0;
out:
xprt_clear_connecting(xprt);
xprt_unlock_connect(xprt, transport);
xprt_wake_pending_tasks(xprt, status);
current_restore_flags(pflags, PF_MEMALLOC);
}
/**
* 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_RDWR);
*/
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;
int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
if (sock == NULL)
return;
if (!xprt->reuseport) {
xs_close(xprt);
return;
}
switch (skst) {
case TCP_FIN_WAIT1:
case TCP_FIN_WAIT2:
case TCP_LAST_ACK:
break;
case TCP_ESTABLISHED:
case TCP_CLOSE_WAIT:
kernel_sock_shutdown(sock, SHUT_RDWR);
trace_rpc_socket_shutdown(xprt, sock);
break;
default:
xs_reset_transport(transport);
}
}
static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
struct socket *sock)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
struct net *net = sock_net(sock->sk);
unsigned long connect_timeout;
unsigned long syn_retries;
unsigned int keepidle;
unsigned int keepcnt;
unsigned int timeo;
unsigned long t;
spin_lock(&xprt->transport_lock);
keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
keepcnt = xprt->timeout->to_retries + 1;
timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
(xprt->timeout->to_retries + 1);
clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
spin_unlock(&xprt->transport_lock);
/* TCP Keepalive options */
sock_set_keepalive(sock->sk);
tcp_sock_set_keepidle(sock->sk, keepidle);
tcp_sock_set_keepintvl(sock->sk, keepidle);
tcp_sock_set_keepcnt(sock->sk, keepcnt);
/* TCP user timeout (see RFC5482) */
tcp_sock_set_user_timeout(sock->sk, timeo);
/* Connect timeout */
connect_timeout = max_t(unsigned long,
DIV_ROUND_UP(xprt->connect_timeout, HZ), 1);
syn_retries = max_t(unsigned long,
READ_ONCE(net->ipv4.sysctl_tcp_syn_retries), 1);
for (t = 0; t <= syn_retries && (1UL << t) < connect_timeout; t++)
;
if (t <= syn_retries)
tcp_sock_set_syncnt(sock->sk, t - 1);
}
static void xs_tcp_do_set_connect_timeout(struct rpc_xprt *xprt,
unsigned long connect_timeout)
{
struct sock_xprt *transport =
container_of(xprt, struct sock_xprt, xprt);
struct rpc_timeout to;
unsigned long initval;
memcpy(&to, xprt->timeout, sizeof(to));
/* Arbitrary lower limit */
initval = max_t(unsigned long, connect_timeout, XS_TCP_INIT_REEST_TO);
to.to_initval = initval;
to.to_maxval = initval;
to.to_retries = 0;
memcpy(&transport->tcp_timeout, &to, sizeof(transport->tcp_timeout));
xprt->timeout = &transport->tcp_timeout;
xprt->connect_timeout = connect_timeout;
}
static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
unsigned long connect_timeout,
unsigned long reconnect_timeout)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
spin_lock(&xprt->transport_lock);
if (reconnect_timeout < xprt->max_reconnect_timeout)
xprt->max_reconnect_timeout = reconnect_timeout;
if (connect_timeout < xprt->connect_timeout)
xs_tcp_do_set_connect_timeout(xprt, connect_timeout);
set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
spin_unlock(&xprt->transport_lock);
}
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;
/* Avoid temporary address, they are bad for long-lived
* connections such as NFS mounts.
* RFC4941, section 3.6 suggests that:
* Individual applications, which have specific
* knowledge about the normal duration of connections,
* MAY override this as appropriate.
*/
if (xs_addr(xprt)->sa_family == PF_INET6) {
ip6_sock_set_addr_preferences(sk,
IPV6_PREFER_SRC_PUBLIC);
}
xs_tcp_set_socket_timeouts(xprt, sock);
tcp_sock_set_nodelay(sk);
lock_sock(sk);
xs_save_old_callbacks(transport, sk);
sk->sk_user_data = xprt;
sk->sk_data_ready = xs_data_ready;
sk->sk_state_change = xs_tcp_state_change;
sk->sk_write_space = xs_tcp_write_space;
sk->sk_error_report = xs_error_report;
sk->sk_use_task_frag = false;
/* socket options */
sock_reset_flag(sk, SOCK_LINGER);
xprt_clear_connected(xprt);
/* Reset to new socket */
transport->sock = sock;
transport->inet = sk;
release_sock(sk);
}
if (!xprt_bound(xprt))
return -ENOTCONN;
xs_set_memalloc(xprt);
xs_stream_start_connect(transport);
/* Tell the socket layer to start connecting... */
set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
}
/**
* xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
* @work: queued work item
*
* Invoked by a work queue tasklet.
*/
static void xs_tcp_setup_socket(struct work_struct *work)
{
struct sock_xprt *transport =
container_of(work, struct sock_xprt, connect_worker.work);
struct socket *sock = transport->sock;
struct rpc_xprt *xprt = &transport->xprt;
int status;
unsigned int pflags = current->flags;
if (atomic_read(&xprt->swapper))
current->flags |= PF_MEMALLOC;
if (xprt_connected(xprt))
goto out;
if (test_and_clear_bit(XPRT_SOCK_CONNECT_SENT,
&transport->sock_state) ||
!sock) {
xs_reset_transport(transport);
sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family,
SOCK_STREAM, IPPROTO_TCP, true);
if (IS_ERR(sock)) {
xprt_wake_pending_tasks(xprt, PTR_ERR(sock));
goto out;
}
}
dprintk("RPC: worker connecting xprt %p via %s to "
"%s (port %s)\n", xprt,
xprt->address_strings[RPC_DISPLAY_PROTO],
xprt->address_strings[RPC_DISPLAY_ADDR],
xprt->address_strings[RPC_DISPLAY_PORT]);
status = xs_tcp_finish_connecting(xprt, sock);
trace_rpc_socket_connect(xprt, sock, status);
dprintk("RPC: %p connect status %d connected %d sock state %d\n",
xprt, -status, xprt_connected(xprt),
sock->sk->sk_state);
switch (status) {
case 0:
case -EINPROGRESS:
/* SYN_SENT! */
set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
fallthrough;
case -EALREADY:
goto out_unlock;
case -EADDRNOTAVAIL:
/* Source port number is unavailable. Try a new one! */
transport->srcport = 0;
status = -EAGAIN;
break;
case -EPERM:
/* Happens, for instance, if a BPF program is preventing
* the connect. Remap the error so upper layers can better
* deal with it.
*/
status = -ECONNREFUSED;
fallthrough;
case -EINVAL:
/* Happens, for instance, if the user specified a link
* local IPv6 address without a scope-id.
*/
case -ECONNREFUSED:
case -ECONNRESET:
case -ENETDOWN:
case -ENETUNREACH:
case -EHOSTUNREACH:
case -EADDRINUSE:
case -ENOBUFS:
break;
default:
printk("%s: connect returned unhandled error %d\n",
__func__, status);
status = -EAGAIN;
}
/* xs_tcp_force_close() wakes tasks with a fixed error code.
* We need to wake them first to ensure the correct error code.
*/
xprt_wake_pending_tasks(xprt, status);
xs_tcp_force_close(xprt);
out:
xprt_clear_connecting(xprt);
out_unlock:
xprt_unlock_connect(xprt, transport);
current_restore_flags(pflags, PF_MEMALLOC);
}
/*
* Transfer the connected socket to @upper_transport, then mark that
* xprt CONNECTED.
*/
static int xs_tcp_tls_finish_connecting(struct rpc_xprt *lower_xprt,
struct sock_xprt *upper_transport)
{
struct sock_xprt *lower_transport =
container_of(lower_xprt, struct sock_xprt, xprt);
struct rpc_xprt *upper_xprt = &upper_transport->xprt;
if (!upper_transport->inet) {
struct socket *sock = lower_transport->sock;
struct sock *sk = sock->sk;
/* Avoid temporary address, they are bad for long-lived
* connections such as NFS mounts.
* RFC4941, section 3.6 suggests that:
* Individual applications, which have specific
* knowledge about the normal duration of connections,
* MAY override this as appropriate.
*/
if (xs_addr(upper_xprt)->sa_family == PF_INET6)
ip6_sock_set_addr_preferences(sk, IPV6_PREFER_SRC_PUBLIC);
xs_tcp_set_socket_timeouts(upper_xprt, sock);
tcp_sock_set_nodelay(sk);
lock_sock(sk);
/* @sk is already connected, so it now has the RPC callbacks.
* Reach into @lower_transport to save the original ones.
*/
upper_transport->old_data_ready = lower_transport->old_data_ready;
upper_transport->old_state_change = lower_transport->old_state_change;
upper_transport->old_write_space = lower_transport->old_write_space;
upper_transport->old_error_report = lower_transport->old_error_report;
sk->sk_user_data = upper_xprt;
/* socket options */
sock_reset_flag(sk, SOCK_LINGER);
xprt_clear_connected(upper_xprt);
upper_transport->sock = sock;
upper_transport->inet = sk;
upper_transport->file = lower_transport->file;
release_sock(sk);
/* Reset lower_transport before shutting down its clnt */
mutex_lock(&lower_transport->recv_mutex);
lower_transport->inet = NULL;
lower_transport->sock = NULL;
lower_transport->file = NULL;
xprt_clear_connected(lower_xprt);
xs_sock_reset_connection_flags(lower_xprt);
xs_stream_reset_connect(lower_transport);
mutex_unlock(&lower_transport->recv_mutex);
}
if (!xprt_bound(upper_xprt))
return -ENOTCONN;
xs_set_memalloc(upper_xprt);
if (!xprt_test_and_set_connected(upper_xprt)) {
upper_xprt->connect_cookie++;
clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
xprt_clear_connecting(upper_xprt);
upper_xprt->stat.connect_count++;
upper_xprt->stat.connect_time += (long)jiffies -
upper_xprt->stat.connect_start;
xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
}
return 0;
}
/**
* xs_tls_handshake_done - TLS handshake completion handler
* @data: address of xprt to wake
* @status: status of handshake
* @peerid: serial number of key containing the remote's identity
*
*/
static void xs_tls_handshake_done(void *data, int status, key_serial_t peerid)
{
struct rpc_xprt *lower_xprt = data;
struct sock_xprt *lower_transport =
container_of(lower_xprt, struct sock_xprt, xprt);
lower_transport->xprt_err = status ? -EACCES : 0;
complete(&lower_transport->handshake_done);
xprt_put(lower_xprt);
}
static int xs_tls_handshake_sync(struct rpc_xprt *lower_xprt, struct xprtsec_parms *xprtsec)
{
struct sock_xprt *lower_transport =
container_of(lower_xprt, struct sock_xprt, xprt);
struct tls_handshake_args args = {
.ta_sock = lower_transport->sock,
.ta_done = xs_tls_handshake_done,
.ta_data = xprt_get(lower_xprt),
.ta_peername = lower_xprt->servername,
};
struct sock *sk = lower_transport->inet;
int rc;
init_completion(&lower_transport->handshake_done);
set_bit(XPRT_SOCK_IGNORE_RECV, &lower_transport->sock_state);
lower_transport->xprt_err = -ETIMEDOUT;
switch (xprtsec->policy) {
case RPC_XPRTSEC_TLS_ANON:
rc = tls_client_hello_anon(&args, GFP_KERNEL);
if (rc)
goto out_put_xprt;
break;
case RPC_XPRTSEC_TLS_X509:
args.ta_my_cert = xprtsec->cert_serial;
args.ta_my_privkey = xprtsec->privkey_serial;
rc = tls_client_hello_x509(&args, GFP_KERNEL);
if (rc)
goto out_put_xprt;
break;
default:
rc = -EACCES;
goto out_put_xprt;
}
rc = wait_for_completion_interruptible_timeout(&lower_transport->handshake_done,
XS_TLS_HANDSHAKE_TO);
if (rc <= 0) {
if (!tls_handshake_cancel(sk)) {
if (rc == 0)
rc = -ETIMEDOUT;
goto out_put_xprt;
}
}
rc = lower_transport->xprt_err;
out:
xs_stream_reset_connect(lower_transport);
clear_bit(XPRT_SOCK_IGNORE_RECV, &lower_transport->sock_state);
return rc;
out_put_xprt:
xprt_put(lower_xprt);
goto out;
}
/**
* xs_tcp_tls_setup_socket - establish a TLS session on a TCP socket
* @work: queued work item
*
* Invoked by a work queue tasklet.
*
* For RPC-with-TLS, there is a two-stage connection process.
*
* The "upper-layer xprt" is visible to the RPC consumer. Once it has
* been marked connected, the consumer knows that a TCP connection and
* a TLS session have been established.
*
* A "lower-layer xprt", created in this function, handles the mechanics
* of connecting the TCP socket, performing the RPC_AUTH_TLS probe, and
* then driving the TLS handshake. Once all that is complete, the upper
* layer xprt is marked connected.
*/
static void xs_tcp_tls_setup_socket(struct work_struct *work)
{
struct sock_xprt *upper_transport =
container_of(work, struct sock_xprt, connect_worker.work);
struct rpc_clnt *upper_clnt = upper_transport->clnt;
struct rpc_xprt *upper_xprt = &upper_transport->xprt;
struct rpc_create_args args = {
.net = upper_xprt->xprt_net,
.protocol = upper_xprt->prot,
.address = (struct sockaddr *)&upper_xprt->addr,
.addrsize = upper_xprt->addrlen,
.timeout = upper_clnt->cl_timeout,
.servername = upper_xprt->servername,
.program = upper_clnt->cl_program,
.prognumber = upper_clnt->cl_prog,
.version = upper_clnt->cl_vers,
.authflavor = RPC_AUTH_TLS,
.cred = upper_clnt->cl_cred,
.xprtsec = {
.policy = RPC_XPRTSEC_NONE,
},
.stats = upper_clnt->cl_stats,
};
unsigned int pflags = current->flags;
struct rpc_clnt *lower_clnt;
struct rpc_xprt *lower_xprt;
int status;
if (atomic_read(&upper_xprt->swapper))
current->flags |= PF_MEMALLOC;
xs_stream_start_connect(upper_transport);
/* This implicitly sends an RPC_AUTH_TLS probe */
lower_clnt = rpc_create(&args);
if (IS_ERR(lower_clnt)) {
trace_rpc_tls_unavailable(upper_clnt, upper_xprt);
clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
xprt_clear_connecting(upper_xprt);
xprt_wake_pending_tasks(upper_xprt, PTR_ERR(lower_clnt));
xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
goto out_unlock;
}
/* RPC_AUTH_TLS probe was successful. Try a TLS handshake on
* the lower xprt.
*/
rcu_read_lock();
lower_xprt = rcu_dereference(lower_clnt->cl_xprt);
rcu_read_unlock();
if (wait_on_bit_lock(&lower_xprt->state, XPRT_LOCKED, TASK_KILLABLE))
goto out_unlock;
status = xs_tls_handshake_sync(lower_xprt, &upper_xprt->xprtsec);
if (status) {
trace_rpc_tls_not_started(upper_clnt, upper_xprt);
goto out_close;
}
status = xs_tcp_tls_finish_connecting(lower_xprt, upper_transport);
if (status)
goto out_close;
xprt_release_write(lower_xprt, NULL);
trace_rpc_socket_connect(upper_xprt, upper_transport->sock, 0);
if (!xprt_test_and_set_connected(upper_xprt)) {
upper_xprt->connect_cookie++;
clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
xprt_clear_connecting(upper_xprt);
upper_xprt->stat.connect_count++;
upper_xprt->stat.connect_time += (long)jiffies -
upper_xprt->stat.connect_start;
xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
}
rpc_shutdown_client(lower_clnt);
out_unlock:
current_restore_flags(pflags, PF_MEMALLOC);
upper_transport->clnt = NULL;
xprt_unlock_connect(upper_xprt, upper_transport);
return;
out_close:
xprt_release_write(lower_xprt, NULL);
rpc_shutdown_client(lower_clnt);
/* xprt_force_disconnect() wakes tasks with a fixed tk_status code.
* Wake them first here to ensure they get our tk_status code.
*/
xprt_wake_pending_tasks(upper_xprt, status);
xs_tcp_force_close(upper_xprt);
xprt_clear_connecting(upper_xprt);
goto out_unlock;
}
/**
* xs_connect - connect a socket to a remote endpoint
* @xprt: pointer to transport structure
* @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_xprt *xprt, struct rpc_task *task)
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
unsigned long delay = 0;
WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
if (transport->sock != NULL) {
dprintk("RPC: xs_connect delayed xprt %p for %lu "
"seconds\n", xprt, xprt->reestablish_timeout / HZ);
delay = xprt_reconnect_delay(xprt);
xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
} else
dprintk("RPC: xs_connect scheduled xprt %p\n", xprt);
transport->clnt = task->tk_client;
queue_delayed_work(xprtiod_workqueue,
&transport->connect_worker,
delay);
}
static void xs_wake_disconnect(struct sock_xprt *transport)
{
if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
xs_tcp_force_close(&transport->xprt);
}
static void xs_wake_write(struct sock_xprt *transport)
{
if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
xprt_write_space(&transport->xprt);
}
static void xs_wake_error(struct sock_xprt *transport)
{
int sockerr;
if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
return;
sockerr = xchg(&transport->xprt_err, 0);
if (sockerr < 0) {
xprt_wake_pending_tasks(&transport->xprt, sockerr);
xs_tcp_force_close(&transport->xprt);
}
}
static void xs_wake_pending(struct sock_xprt *transport)
{
if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
}
static void xs_error_handle(struct work_struct *work)
{
struct sock_xprt *transport = container_of(work,
struct sock_xprt, error_worker);
xs_wake_disconnect(transport);
xs_wake_write(transport);
xs_wake_error(transport);
xs_wake_pending(transport);
}
/**
* xs_local_print_stats - display AF_LOCAL socket-specific stats
* @xprt: rpc_xprt struct containing statistics
* @seq: output file
*
*/
static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
{
long idle_time = 0;
if (xprt_connected(xprt))
idle_time = (long)(jiffies - xprt->last_used) / HZ;
seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
"%llu %llu %lu %llu %llu\n",
xprt->stat.bind_count,
xprt->stat.connect_count,
xprt->stat.connect_time / HZ,
idle_time,
xprt->stat.sends,
xprt->stat.recvs,
xprt->stat.bad_xids,
xprt->stat.req_u,
xprt->stat.bklog_u,
xprt->stat.max_slots,
xprt->stat.sending_u,
xprt->stat.pending_u);
}
/**
* xs_udp_print_stats - display UDP socket-specific 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 %llu %llu "
"%lu %llu %llu\n",
transport->srcport,
xprt->stat.bind_count,
xprt->stat.sends,
xprt->stat.recvs,
xprt->stat.bad_xids,
xprt->stat.req_u,
xprt->stat.bklog_u,
xprt->stat.max_slots,
xprt->stat.sending_u,
xprt->stat.pending_u);
}
/**
* xs_tcp_print_stats - display TCP socket-specific 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 "
"%llu %llu %lu %llu %llu\n",
transport->srcport,
xprt->stat.bind_count,
xprt->stat.connect_count,
xprt->stat.connect_time / HZ,
idle_time,
xprt->stat.sends,
xprt->stat.recvs,
xprt->stat.bad_xids,
xprt->stat.req_u,
xprt->stat.bklog_u,
xprt->stat.max_slots,
xprt->stat.sending_u,
xprt->stat.pending_u);
}
/*
* Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
* we allocate pages instead doing a kmalloc like rpc_malloc is because we want
* to use the server side send routines.
*/
static int bc_malloc(struct rpc_task *task)
{
struct rpc_rqst *rqst = task->tk_rqstp;
size_t size = rqst->rq_callsize;
struct page *page;
struct rpc_buffer *buf;
if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
size);
return -EINVAL;
}
page = alloc_page(GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
if (!page)
return -ENOMEM;
buf = page_address(page);
buf->len = PAGE_SIZE;
rqst->rq_buffer = buf->data;
rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
return 0;
}
/*
* Free the space allocated in the bc_alloc routine
*/
static void bc_free(struct rpc_task *task)
{
void *buffer = task->tk_rqstp->rq_buffer;
struct rpc_buffer *buf;
buf = container_of(buffer, struct rpc_buffer, data);
free_page((unsigned long)buf);
}
static int bc_sendto(struct rpc_rqst *req)
{
struct xdr_buf *xdr = &req->rq_snd_buf;
struct sock_xprt *transport =
container_of(req->rq_xprt, struct sock_xprt, xprt);
struct msghdr msg = {
.msg_flags = 0,
};
rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
(u32)xdr->len);
unsigned int sent = 0;
int err;
req->rq_xtime = ktime_get();
err = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
if (err < 0)
return err;
err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
xdr_free_bvec(xdr);
if (err < 0 || sent != (xdr->len + sizeof(marker)))
return -EAGAIN;
return sent;
}
/**
* bc_send_request - Send a backchannel Call on a TCP socket
* @req: rpc_rqst containing Call message to be sent
*
* xpt_mutex ensures @rqstp's whole message is written to the socket
* without interruption.
*
* Return values:
* %0 if the message was sent successfully
* %ENOTCONN if the message was not sent
*/
static int bc_send_request(struct rpc_rqst *req)
{
struct svc_xprt *xprt;
int len;
/*
* Get the server socket associated with this callback xprt
*/
xprt = req->rq_xprt->bc_xprt;
/*
* Grab the mutex to serialize data as the connection is shared
* with the fore channel
*/
mutex_lock(&xprt->xpt_mutex);
if (test_bit(XPT_DEAD, &xprt->xpt_flags))
len = -ENOTCONN;
else
len = bc_sendto(req);
mutex_unlock(&xprt->xpt_mutex);
if (len > 0)
len = 0;
return len;
}
static void bc_close(struct rpc_xprt *xprt)
{
xprt_disconnect_done(xprt);
}
static void bc_destroy(struct rpc_xprt *xprt)
{
dprintk("RPC: bc_destroy xprt %p\n", xprt);
xs_xprt_free(xprt);
module_put(THIS_MODULE);
}
static const struct rpc_xprt_ops xs_local_ops = {
.reserve_xprt = xprt_reserve_xprt,
.release_xprt = xprt_release_xprt,
.alloc_slot = xprt_alloc_slot,
.free_slot = xprt_free_slot,
.rpcbind = xs_local_rpcbind,
.set_port = xs_local_set_port,
.connect = xs_local_connect,
.buf_alloc = rpc_malloc,
.buf_free = rpc_free,
.prepare_request = xs_stream_prepare_request,
.send_request = xs_local_send_request,
.abort_send_request = xs_stream_abort_send_request,
.wait_for_reply_request = xprt_wait_for_reply_request_def,
.close = xs_close,
.destroy = xs_destroy,
.print_stats = xs_local_print_stats,
.enable_swap = xs_enable_swap,
.disable_swap = xs_disable_swap,
};
static const 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,
.alloc_slot = xprt_alloc_slot,
.free_slot = xprt_free_slot,
.rpcbind = rpcb_getport_async,
.set_port = xs_set_port,
.connect = xs_connect,
.get_srcaddr = xs_sock_srcaddr,
.get_srcport = xs_sock_srcport,
.buf_alloc = rpc_malloc,
.buf_free = rpc_free,
.send_request = xs_udp_send_request,
.wait_for_reply_request = xprt_wait_for_reply_request_rtt,
.timer = xs_udp_timer,
.release_request = xprt_release_rqst_cong,
.close = xs_close,
.destroy = xs_destroy,
.print_stats = xs_udp_print_stats,
.enable_swap = xs_enable_swap,
.disable_swap = xs_disable_swap,
.inject_disconnect = xs_inject_disconnect,
};
static const struct rpc_xprt_ops xs_tcp_ops = {
.reserve_xprt = xprt_reserve_xprt,
.release_xprt = xprt_release_xprt,
.alloc_slot = xprt_alloc_slot,
.free_slot = xprt_free_slot,
.rpcbind = rpcb_getport_async,
.set_port = xs_set_port,
.connect = xs_connect,
.get_srcaddr = xs_sock_srcaddr,
.get_srcport = xs_sock_srcport,
.buf_alloc = rpc_malloc,
.buf_free = rpc_free,
.prepare_request = xs_stream_prepare_request,
.send_request = xs_tcp_send_request,
.abort_send_request = xs_stream_abort_send_request,
.wait_for_reply_request = xprt_wait_for_reply_request_def,
.close = xs_tcp_shutdown,
.destroy = xs_des