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|
/*
* GPL HEADER START
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 only,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License version 2 for more details (a copy is included
* in the LICENSE file that accompanied this code).
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; If not, see
* http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*
* GPL HEADER END
*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Use is subject to license terms.
*
* Copyright (c) 2011, 2012, Intel Corporation.
*/
/*
* This file is part of Lustre, http://www.lustre.org/
* Lustre is a trademark of Sun Microsystems, Inc.
*/
#include "socklnd.h"
int
ksocknal_lib_get_conn_addrs (ksock_conn_t *conn)
{
int rc = libcfs_sock_getaddr(conn->ksnc_sock, 1,
&conn->ksnc_ipaddr,
&conn->ksnc_port);
/* Didn't need the {get,put}connsock dance to deref ksnc_sock... */
LASSERT (!conn->ksnc_closing);
if (rc != 0) {
CERROR ("Error %d getting sock peer IP\n", rc);
return rc;
}
rc = libcfs_sock_getaddr(conn->ksnc_sock, 0,
&conn->ksnc_myipaddr, NULL);
if (rc != 0) {
CERROR ("Error %d getting sock local IP\n", rc);
return rc;
}
return 0;
}
int
ksocknal_lib_zc_capable(ksock_conn_t *conn)
{
int caps = conn->ksnc_sock->sk->sk_route_caps;
if (conn->ksnc_proto == &ksocknal_protocol_v1x)
return 0;
/* ZC if the socket supports scatter/gather and doesn't need software
* checksums */
return ((caps & NETIF_F_SG) != 0 && (caps & NETIF_F_ALL_CSUM) != 0);
}
int
ksocknal_lib_send_iov (ksock_conn_t *conn, ksock_tx_t *tx)
{
struct socket *sock = conn->ksnc_sock;
int nob;
int rc;
if (*ksocknal_tunables.ksnd_enable_csum && /* checksum enabled */
conn->ksnc_proto == &ksocknal_protocol_v2x && /* V2.x connection */
tx->tx_nob == tx->tx_resid && /* frist sending */
tx->tx_msg.ksm_csum == 0) /* not checksummed */
ksocknal_lib_csum_tx(tx);
/* NB we can't trust socket ops to either consume our iovs
* or leave them alone. */
{
#if SOCKNAL_SINGLE_FRAG_TX
struct iovec scratch;
struct iovec *scratchiov = &scratch;
unsigned int niov = 1;
#else
struct iovec *scratchiov = conn->ksnc_scheduler->kss_scratch_iov;
unsigned int niov = tx->tx_niov;
#endif
struct msghdr msg = {
.msg_name = NULL,
.msg_namelen = 0,
.msg_iov = scratchiov,
.msg_iovlen = niov,
.msg_control = NULL,
.msg_controllen = 0,
.msg_flags = MSG_DONTWAIT
};
mm_segment_t oldmm = get_fs();
int i;
for (nob = i = 0; i < niov; i++) {
scratchiov[i] = tx->tx_iov[i];
nob += scratchiov[i].iov_len;
}
if (!list_empty(&conn->ksnc_tx_queue) ||
nob < tx->tx_resid)
msg.msg_flags |= MSG_MORE;
set_fs (KERNEL_DS);
rc = sock_sendmsg(sock, &msg, nob);
set_fs (oldmm);
}
return rc;
}
int
ksocknal_lib_send_kiov (ksock_conn_t *conn, ksock_tx_t *tx)
{
struct socket *sock = conn->ksnc_sock;
lnet_kiov_t *kiov = tx->tx_kiov;
int rc;
int nob;
/* Not NOOP message */
LASSERT (tx->tx_lnetmsg != NULL);
/* NB we can't trust socket ops to either consume our iovs
* or leave them alone. */
if (tx->tx_msg.ksm_zc_cookies[0] != 0) {
/* Zero copy is enabled */
struct sock *sk = sock->sk;
struct page *page = kiov->kiov_page;
int offset = kiov->kiov_offset;
int fragsize = kiov->kiov_len;
int msgflg = MSG_DONTWAIT;
CDEBUG(D_NET, "page %p + offset %x for %d\n",
page, offset, kiov->kiov_len);
if (!list_empty(&conn->ksnc_tx_queue) ||
fragsize < tx->tx_resid)
msgflg |= MSG_MORE;
if (sk->sk_prot->sendpage != NULL) {
rc = sk->sk_prot->sendpage(sk, page,
offset, fragsize, msgflg);
} else {
rc = cfs_tcp_sendpage(sk, page, offset, fragsize,
msgflg);
}
} else {
#if SOCKNAL_SINGLE_FRAG_TX || !SOCKNAL_RISK_KMAP_DEADLOCK
struct iovec scratch;
struct iovec *scratchiov = &scratch;
unsigned int niov = 1;
#else
#ifdef CONFIG_HIGHMEM
#warning "XXX risk of kmap deadlock on multiple frags..."
#endif
struct iovec *scratchiov = conn->ksnc_scheduler->kss_scratch_iov;
unsigned int niov = tx->tx_nkiov;
#endif
struct msghdr msg = {
.msg_name = NULL,
.msg_namelen = 0,
.msg_iov = scratchiov,
.msg_iovlen = niov,
.msg_control = NULL,
.msg_controllen = 0,
.msg_flags = MSG_DONTWAIT
};
mm_segment_t oldmm = get_fs();
int i;
for (nob = i = 0; i < niov; i++) {
scratchiov[i].iov_base = kmap(kiov[i].kiov_page) +
kiov[i].kiov_offset;
nob += scratchiov[i].iov_len = kiov[i].kiov_len;
}
if (!list_empty(&conn->ksnc_tx_queue) ||
nob < tx->tx_resid)
msg.msg_flags |= MSG_MORE;
set_fs (KERNEL_DS);
rc = sock_sendmsg(sock, &msg, nob);
set_fs (oldmm);
for (i = 0; i < niov; i++)
kunmap(kiov[i].kiov_page);
}
return rc;
}
void
ksocknal_lib_eager_ack (ksock_conn_t *conn)
{
int opt = 1;
mm_segment_t oldmm = get_fs();
struct socket *sock = conn->ksnc_sock;
/* Remind the socket to ACK eagerly. If I don't, the socket might
* think I'm about to send something it could piggy-back the ACK
* on, introducing delay in completing zero-copy sends in my
* peer. */
set_fs(KERNEL_DS);
sock->ops->setsockopt (sock, SOL_TCP, TCP_QUICKACK,
(char *)&opt, sizeof (opt));
set_fs(oldmm);
}
int
ksocknal_lib_recv_iov (ksock_conn_t *conn)
{
#if SOCKNAL_SINGLE_FRAG_RX
struct iovec scratch;
struct iovec *scratchiov = &scratch;
unsigned int niov = 1;
#else
struct iovec *scratchiov = conn->ksnc_scheduler->kss_scratch_iov;
unsigned int niov = conn->ksnc_rx_niov;
#endif
struct iovec *iov = conn->ksnc_rx_iov;
struct msghdr msg = {
.msg_name = NULL,
.msg_namelen = 0,
.msg_iov = scratchiov,
.msg_iovlen = niov,
.msg_control = NULL,
.msg_controllen = 0,
.msg_flags = 0
};
mm_segment_t oldmm = get_fs();
int nob;
int i;
int rc;
int fragnob;
int sum;
__u32 saved_csum;
/* NB we can't trust socket ops to either consume our iovs
* or leave them alone. */
LASSERT (niov > 0);
for (nob = i = 0; i < niov; i++) {
scratchiov[i] = iov[i];
nob += scratchiov[i].iov_len;
}
LASSERT (nob <= conn->ksnc_rx_nob_wanted);
set_fs (KERNEL_DS);
rc = sock_recvmsg (conn->ksnc_sock, &msg, nob, MSG_DONTWAIT);
/* NB this is just a boolean..........................^ */
set_fs (oldmm);
saved_csum = 0;
if (conn->ksnc_proto == &ksocknal_protocol_v2x) {
saved_csum = conn->ksnc_msg.ksm_csum;
conn->ksnc_msg.ksm_csum = 0;
}
if (saved_csum != 0) {
/* accumulate checksum */
for (i = 0, sum = rc; sum > 0; i++, sum -= fragnob) {
LASSERT (i < niov);
fragnob = iov[i].iov_len;
if (fragnob > sum)
fragnob = sum;
conn->ksnc_rx_csum = ksocknal_csum(conn->ksnc_rx_csum,
iov[i].iov_base, fragnob);
}
conn->ksnc_msg.ksm_csum = saved_csum;
}
return rc;
}
static void
ksocknal_lib_kiov_vunmap(void *addr)
{
if (addr == NULL)
return;
vunmap(addr);
}
static void *
ksocknal_lib_kiov_vmap(lnet_kiov_t *kiov, int niov,
struct iovec *iov, struct page **pages)
{
void *addr;
int nob;
int i;
if (!*ksocknal_tunables.ksnd_zc_recv || pages == NULL)
return NULL;
LASSERT (niov <= LNET_MAX_IOV);
if (niov < 2 ||
niov < *ksocknal_tunables.ksnd_zc_recv_min_nfrags)
return NULL;
for (nob = i = 0; i < niov; i++) {
if ((kiov[i].kiov_offset != 0 && i > 0) ||
(kiov[i].kiov_offset + kiov[i].kiov_len != PAGE_CACHE_SIZE && i < niov - 1))
return NULL;
pages[i] = kiov[i].kiov_page;
nob += kiov[i].kiov_len;
}
addr = vmap(pages, niov, VM_MAP, PAGE_KERNEL);
if (addr == NULL)
return NULL;
iov->iov_base = addr + kiov[0].kiov_offset;
iov->iov_len = nob;
return addr;
}
int
ksocknal_lib_recv_kiov (ksock_conn_t *conn)
{
#if SOCKNAL_SINGLE_FRAG_RX || !SOCKNAL_RISK_KMAP_DEADLOCK
struct iovec scratch;
struct iovec *scratchiov = &scratch;
struct page **pages = NULL;
unsigned int niov = 1;
#else
#ifdef CONFIG_HIGHMEM
#warning "XXX risk of kmap deadlock on multiple frags..."
#endif
struct iovec *scratchiov = conn->ksnc_scheduler->kss_scratch_iov;
struct page **pages = conn->ksnc_scheduler->kss_rx_scratch_pgs;
unsigned int niov = conn->ksnc_rx_nkiov;
#endif
lnet_kiov_t *kiov = conn->ksnc_rx_kiov;
struct msghdr msg = {
.msg_name = NULL,
.msg_namelen = 0,
.msg_iov = scratchiov,
.msg_control = NULL,
.msg_controllen = 0,
.msg_flags = 0
};
mm_segment_t oldmm = get_fs();
int nob;
int i;
int rc;
void *base;
void *addr;
int sum;
int fragnob;
/* NB we can't trust socket ops to either consume our iovs
* or leave them alone. */
addr = ksocknal_lib_kiov_vmap(kiov, niov, scratchiov, pages);
if (addr != NULL) {
nob = scratchiov[0].iov_len;
msg.msg_iovlen = 1;
} else {
for (nob = i = 0; i < niov; i++) {
nob += scratchiov[i].iov_len = kiov[i].kiov_len;
scratchiov[i].iov_base = kmap(kiov[i].kiov_page) +
kiov[i].kiov_offset;
}
msg.msg_iovlen = niov;
}
LASSERT (nob <= conn->ksnc_rx_nob_wanted);
set_fs (KERNEL_DS);
rc = sock_recvmsg (conn->ksnc_sock, &msg, nob, MSG_DONTWAIT);
/* NB this is just a boolean.......................^ */
set_fs (oldmm);
if (conn->ksnc_msg.ksm_csum != 0) {
for (i = 0, sum = rc; sum > 0; i++, sum -= fragnob) {
LASSERT (i < niov);
/* Dang! have to kmap again because I have nowhere to stash the
* mapped address. But by doing it while the page is still
* mapped, the kernel just bumps the map count and returns me
* the address it stashed. */
base = kmap(kiov[i].kiov_page) + kiov[i].kiov_offset;
fragnob = kiov[i].kiov_len;
if (fragnob > sum)
fragnob = sum;
conn->ksnc_rx_csum = ksocknal_csum(conn->ksnc_rx_csum,
base, fragnob);
kunmap(kiov[i].kiov_page);
}
}
if (addr != NULL) {
ksocknal_lib_kiov_vunmap(addr);
} else {
for (i = 0; i < niov; i++)
kunmap(kiov[i].kiov_page);
}
return (rc);
}
void
ksocknal_lib_csum_tx(ksock_tx_t *tx)
{
int i;
__u32 csum;
void *base;
LASSERT(tx->tx_iov[0].iov_base == (void *)&tx->tx_msg);
LASSERT(tx->tx_conn != NULL);
LASSERT(tx->tx_conn->ksnc_proto == &ksocknal_protocol_v2x);
tx->tx_msg.ksm_csum = 0;
csum = ksocknal_csum(~0, (void *)tx->tx_iov[0].iov_base,
tx->tx_iov[0].iov_len);
if (tx->tx_kiov != NULL) {
for (i = 0; i < tx->tx_nkiov; i++) {
base = kmap(tx->tx_kiov[i].kiov_page) +
tx->tx_kiov[i].kiov_offset;
csum = ksocknal_csum(csum, base, tx->tx_kiov[i].kiov_len);
kunmap(tx->tx_kiov[i].kiov_page);
}
} else {
for (i = 1; i < tx->tx_niov; i++)
csum = ksocknal_csum(csum, tx->tx_iov[i].iov_base,
tx->tx_iov[i].iov_len);
}
if (*ksocknal_tunables.ksnd_inject_csum_error) {
csum++;
*ksocknal_tunables.ksnd_inject_csum_error = 0;
}
tx->tx_msg.ksm_csum = csum;
}
int
ksocknal_lib_get_conn_tunables (ksock_conn_t *conn, int *txmem, int *rxmem, int *nagle)
{
mm_segment_t oldmm = get_fs ();
struct socket *sock = conn->ksnc_sock;
int len;
int rc;
rc = ksocknal_connsock_addref(conn);
if (rc != 0) {
LASSERT (conn->ksnc_closing);
*txmem = *rxmem = *nagle = 0;
return (-ESHUTDOWN);
}
rc = libcfs_sock_getbuf(sock, txmem, rxmem);
if (rc == 0) {
len = sizeof(*nagle);
set_fs(KERNEL_DS);
rc = sock->ops->getsockopt(sock, SOL_TCP, TCP_NODELAY,
(char *)nagle, &len);
set_fs(oldmm);
}
ksocknal_connsock_decref(conn);
if (rc == 0)
*nagle = !*nagle;
else
*txmem = *rxmem = *nagle = 0;
return (rc);
}
int
ksocknal_lib_setup_sock (struct socket *sock)
{
mm_segment_t oldmm = get_fs ();
int rc;
int option;
int keep_idle;
int keep_intvl;
int keep_count;
int do_keepalive;
struct linger linger;
sock->sk->sk_allocation = GFP_NOFS;
/* Ensure this socket aborts active sends immediately when we close
* it. */
linger.l_onoff = 0;
linger.l_linger = 0;
set_fs (KERNEL_DS);
rc = sock_setsockopt (sock, SOL_SOCKET, SO_LINGER,
(char *)&linger, sizeof (linger));
set_fs (oldmm);
if (rc != 0) {
CERROR ("Can't set SO_LINGER: %d\n", rc);
return (rc);
}
option = -1;
set_fs (KERNEL_DS);
rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_LINGER2,
(char *)&option, sizeof (option));
set_fs (oldmm);
if (rc != 0) {
CERROR ("Can't set SO_LINGER2: %d\n", rc);
return (rc);
}
if (!*ksocknal_tunables.ksnd_nagle) {
option = 1;
set_fs (KERNEL_DS);
rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_NODELAY,
(char *)&option, sizeof (option));
set_fs (oldmm);
if (rc != 0) {
CERROR ("Can't disable nagle: %d\n", rc);
return (rc);
}
}
rc = libcfs_sock_setbuf(sock,
*ksocknal_tunables.ksnd_tx_buffer_size,
*ksocknal_tunables.ksnd_rx_buffer_size);
if (rc != 0) {
CERROR ("Can't set buffer tx %d, rx %d buffers: %d\n",
*ksocknal_tunables.ksnd_tx_buffer_size,
*ksocknal_tunables.ksnd_rx_buffer_size, rc);
return (rc);
}
/* TCP_BACKOFF_* sockopt tunables unsupported in stock kernels */
/* snapshot tunables */
keep_idle = *ksocknal_tunables.ksnd_keepalive_idle;
keep_count = *ksocknal_tunables.ksnd_keepalive_count;
keep_intvl = *ksocknal_tunables.ksnd_keepalive_intvl;
do_keepalive = (keep_idle > 0 && keep_count > 0 && keep_intvl > 0);
option = (do_keepalive ? 1 : 0);
set_fs (KERNEL_DS);
rc = sock_setsockopt (sock, SOL_SOCKET, SO_KEEPALIVE,
(char *)&option, sizeof (option));
set_fs (oldmm);
if (rc != 0) {
CERROR ("Can't set SO_KEEPALIVE: %d\n", rc);
return (rc);
}
if (!do_keepalive)
return (0);
set_fs (KERNEL_DS);
rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_KEEPIDLE,
(char *)&keep_idle, sizeof (keep_idle));
set_fs (oldmm);
if (rc != 0) {
CERROR ("Can't set TCP_KEEPIDLE: %d\n", rc);
return (rc);
}
set_fs (KERNEL_DS);
rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_KEEPINTVL,
(char *)&keep_intvl, sizeof (keep_intvl));
set_fs (oldmm);
if (rc != 0) {
CERROR ("Can't set TCP_KEEPINTVL: %d\n", rc);
return (rc);
}
set_fs (KERNEL_DS);
rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_KEEPCNT,
(char *)&keep_count, sizeof (keep_count));
set_fs (oldmm);
if (rc != 0) {
CERROR ("Can't set TCP_KEEPCNT: %d\n", rc);
return (rc);
}
return (0);
}
void
ksocknal_lib_push_conn (ksock_conn_t *conn)
{
struct sock *sk;
struct tcp_sock *tp;
int nonagle;
int val = 1;
int rc;
mm_segment_t oldmm;
rc = ksocknal_connsock_addref(conn);
if (rc != 0) /* being shut down */
return;
sk = conn->ksnc_sock->sk;
tp = tcp_sk(sk);
lock_sock (sk);
nonagle = tp->nonagle;
tp->nonagle = 1;
release_sock (sk);
oldmm = get_fs ();
set_fs (KERNEL_DS);
rc = sk->sk_prot->setsockopt (sk, SOL_TCP, TCP_NODELAY,
(char *)&val, sizeof (val));
LASSERT (rc == 0);
set_fs (oldmm);
lock_sock (sk);
tp->nonagle = nonagle;
release_sock (sk);
ksocknal_connsock_decref(conn);
}
extern void ksocknal_read_callback (ksock_conn_t *conn);
extern void ksocknal_write_callback (ksock_conn_t *conn);
/*
* socket call back in Linux
*/
static void
ksocknal_data_ready (struct sock *sk)
{
ksock_conn_t *conn;
/* interleave correctly with closing sockets... */
LASSERT(!in_irq());
read_lock(&ksocknal_data.ksnd_global_lock);
conn = sk->sk_user_data;
if (conn == NULL) { /* raced with ksocknal_terminate_conn */
LASSERT (sk->sk_data_ready != &ksocknal_data_ready);
sk->sk_data_ready (sk);
} else
ksocknal_read_callback(conn);
read_unlock(&ksocknal_data.ksnd_global_lock);
}
static void
ksocknal_write_space (struct sock *sk)
{
ksock_conn_t *conn;
int wspace;
int min_wpace;
/* interleave correctly with closing sockets... */
LASSERT(!in_irq());
read_lock(&ksocknal_data.ksnd_global_lock);
conn = sk->sk_user_data;
wspace = SOCKNAL_WSPACE(sk);
min_wpace = SOCKNAL_MIN_WSPACE(sk);
CDEBUG(D_NET, "sk %p wspace %d low water %d conn %p%s%s%s\n",
sk, wspace, min_wpace, conn,
(conn == NULL) ? "" : (conn->ksnc_tx_ready ?
" ready" : " blocked"),
(conn == NULL) ? "" : (conn->ksnc_tx_scheduled ?
" scheduled" : " idle"),
(conn == NULL) ? "" : (list_empty (&conn->ksnc_tx_queue) ?
" empty" : " queued"));
if (conn == NULL) { /* raced with ksocknal_terminate_conn */
LASSERT (sk->sk_write_space != &ksocknal_write_space);
sk->sk_write_space (sk);
read_unlock(&ksocknal_data.ksnd_global_lock);
return;
}
if (wspace >= min_wpace) { /* got enough space */
ksocknal_write_callback(conn);
/* Clear SOCK_NOSPACE _after_ ksocknal_write_callback so the
* ENOMEM check in ksocknal_transmit is race-free (think about
* it). */
clear_bit (SOCK_NOSPACE, &sk->sk_socket->flags);
}
read_unlock(&ksocknal_data.ksnd_global_lock);
}
void
ksocknal_lib_save_callback(struct socket *sock, ksock_conn_t *conn)
{
conn->ksnc_saved_data_ready = sock->sk->sk_data_ready;
conn->ksnc_saved_write_space = sock->sk->sk_write_space;
}
void
ksocknal_lib_set_callback(struct socket *sock, ksock_conn_t *conn)
{
sock->sk->sk_user_data = conn;
sock->sk->sk_data_ready = ksocknal_data_ready;
sock->sk->sk_write_space = ksocknal_write_space;
return;
}
void
ksocknal_lib_reset_callback(struct socket *sock, ksock_conn_t *conn)
{
/* Remove conn's network callbacks.
* NB I _have_ to restore the callback, rather than storing a noop,
* since the socket could survive past this module being unloaded!! */
sock->sk->sk_data_ready = conn->ksnc_saved_data_ready;
sock->sk->sk_write_space = conn->ksnc_saved_write_space;
/* A callback could be in progress already; they hold a read lock
* on ksnd_global_lock (to serialise with me) and NOOP if
* sk_user_data is NULL. */
sock->sk->sk_user_data = NULL;
return ;
}
int
ksocknal_lib_memory_pressure(ksock_conn_t *conn)
{
int rc = 0;
ksock_sched_t *sched;
sched = conn->ksnc_scheduler;
spin_lock_bh(&sched->kss_lock);
if (!SOCK_TEST_NOSPACE(conn->ksnc_sock) &&
!conn->ksnc_tx_ready) {
/* SOCK_NOSPACE is set when the socket fills
* and cleared in the write_space callback
* (which also sets ksnc_tx_ready). If
* SOCK_NOSPACE and ksnc_tx_ready are BOTH
* zero, I didn't fill the socket and
* write_space won't reschedule me, so I
* return -ENOMEM to get my caller to retry
* after a timeout */
rc = -ENOMEM;
}
spin_unlock_bh(&sched->kss_lock);
return rc;
}
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