1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
7 # if CONFIG_SYSCTL && !CFS_SYSFS_MODULE_PARM
8 static ctl_table ksocknal_ctl_table[21];
10 ctl_table ksocknal_top_ctl_table[] = {
11 {200, "socknal", NULL, 0, 0555, ksocknal_ctl_table},
16 ksocknal_lib_tunables_init ()
21 ksocknal_ctl_table[i++] = (ctl_table)
22 {j++, "timeout", ksocknal_tunables.ksnd_timeout,
23 sizeof (int), 0644, NULL, &proc_dointvec};
24 ksocknal_ctl_table[i++] = (ctl_table)
25 {j++, "credits", ksocknal_tunables.ksnd_credits,
26 sizeof (int), 0444, NULL, &proc_dointvec};
27 ksocknal_ctl_table[i++] = (ctl_table)
28 {j++, "peer_credits", ksocknal_tunables.ksnd_peercredits,
29 sizeof (int), 0444, NULL, &proc_dointvec};
30 ksocknal_ctl_table[i++] = (ctl_table)
31 {j++, "nconnds", ksocknal_tunables.ksnd_nconnds,
32 sizeof (int), 0444, NULL, &proc_dointvec};
33 ksocknal_ctl_table[i++] = (ctl_table)
34 {j++, "min_reconnectms", ksocknal_tunables.ksnd_min_reconnectms,
35 sizeof (int), 0444, NULL, &proc_dointvec};
36 ksocknal_ctl_table[i++] = (ctl_table)
37 {j++, "max_reconnectms", ksocknal_tunables.ksnd_max_reconnectms,
38 sizeof (int), 0444, NULL, &proc_dointvec};
39 ksocknal_ctl_table[i++] = (ctl_table)
40 {j++, "eager_ack", ksocknal_tunables.ksnd_eager_ack,
41 sizeof (int), 0644, NULL, &proc_dointvec};
42 ksocknal_ctl_table[i++] = (ctl_table)
43 {j++, "zero_copy", ksocknal_tunables.ksnd_zc_min_frag,
44 sizeof (int), 0644, NULL, &proc_dointvec};
45 ksocknal_ctl_table[i++] = (ctl_table)
46 {j++, "typed", ksocknal_tunables.ksnd_typed_conns,
47 sizeof (int), 0444, NULL, &proc_dointvec};
48 ksocknal_ctl_table[i++] = (ctl_table)
49 {j++, "min_bulk", ksocknal_tunables.ksnd_min_bulk,
50 sizeof (int), 0644, NULL, &proc_dointvec};
51 ksocknal_ctl_table[i++] = (ctl_table)
52 {j++, "rx_buffer_size", ksocknal_tunables.ksnd_rx_buffer_size,
53 sizeof(int), 0644, NULL, &proc_dointvec};
54 ksocknal_ctl_table[i++] = (ctl_table)
55 {j++, "tx_buffer_size", ksocknal_tunables.ksnd_tx_buffer_size,
56 sizeof(int), 0644, NULL, &proc_dointvec};
57 ksocknal_ctl_table[i++] = (ctl_table)
58 {j++, "nagle", ksocknal_tunables.ksnd_nagle,
59 sizeof(int), 0644, NULL, &proc_dointvec};
61 ksocknal_ctl_table[i++] = (ctl_table)
62 {j++, "irq_affinity", ksocknal_tunables.ksnd_irq_affinity,
63 sizeof(int), 0644, NULL, &proc_dointvec};
65 ksocknal_ctl_table[i++] = (ctl_table)
66 {j++, "keepalive_idle", ksocknal_tunables.ksnd_keepalive_idle,
67 sizeof(int), 0644, NULL, &proc_dointvec};
68 ksocknal_ctl_table[i++] = (ctl_table)
69 {j++, "keepalive_count", ksocknal_tunables.ksnd_keepalive_count,
70 sizeof(int), 0644, NULL, &proc_dointvec};
71 ksocknal_ctl_table[i++] = (ctl_table)
72 {j++, "keepalive_intvl", ksocknal_tunables.ksnd_keepalive_intvl,
73 sizeof(int), 0644, NULL, &proc_dointvec};
74 #ifdef SOCKNAL_BACKOFF
75 ksocknal_ctl_table[i++] = (ctl_table)
76 {j++, "backoff_init", ksocknal_tunables.ksnd_backoff_init,
77 sizeof(int), 0644, NULL, &proc_dointvec};
78 ksocknal_ctl_table[i++] = (ctl_table)
79 {j++, "backoff_max", ksocknal_tunables.ksnd_backoff_max,
80 sizeof(int), 0644, NULL, &proc_dointvec};
84 LASSERT (i < sizeof(ksocknal_ctl_table)/sizeof(ksocknal_ctl_table[0]));
86 ksocknal_tunables.ksnd_sysctl =
87 cfs_register_sysctl_table(ksocknal_top_ctl_table, 0);
89 if (ksocknal_tunables.ksnd_sysctl == NULL)
90 CWARN("Can't setup /proc tunables\n");
96 ksocknal_lib_tunables_fini ()
98 if (ksocknal_tunables.ksnd_sysctl != NULL)
99 cfs_unregister_sysctl_table(ksocknal_tunables.ksnd_sysctl);
103 ksocknal_lib_tunables_init ()
109 ksocknal_lib_tunables_fini ()
112 #endif /* # if CONFIG_SYSCTL && !CFS_SYSFS_MODULE_PARM */
115 ksocknal_lib_bind_irq (unsigned int irq)
117 #if (defined(CONFIG_SMP) && CPU_AFFINITY)
121 ksock_irqinfo_t *info;
122 char *argv[] = {"/bin/sh",
126 char *envp[] = {"HOME=/",
127 "PATH=/sbin:/bin:/usr/sbin:/usr/bin",
130 LASSERT (irq < NR_IRQS);
131 if (irq == 0) /* software NIC or affinity disabled */
134 info = &ksocknal_data.ksnd_irqinfo[irq];
136 write_lock_bh (&ksocknal_data.ksnd_global_lock);
138 LASSERT (info->ksni_valid);
139 bind = !info->ksni_bound;
140 info->ksni_bound = 1;
142 write_unlock_bh (&ksocknal_data.ksnd_global_lock);
144 if (!bind) /* bound already */
147 cpu = ksocknal_irqsched2cpu(info->ksni_sched);
148 snprintf (cmdline, sizeof (cmdline),
149 "echo %d > /proc/irq/%u/smp_affinity", 1 << cpu, irq);
151 LCONSOLE_INFO("Binding irq %u to CPU %d with cmd: %s\n",
154 /* FIXME: Find a better method of setting IRQ affinity...
157 USERMODEHELPER(argv[0], argv, envp);
162 ksocknal_lib_get_conn_addrs (ksock_conn_t *conn)
164 int rc = libcfs_sock_getaddr(conn->ksnc_sock, 1,
168 /* Didn't need the {get,put}connsock dance to deref ksnc_sock... */
169 LASSERT (!conn->ksnc_closing);
172 CERROR ("Error %d getting sock peer IP\n", rc);
176 rc = libcfs_sock_getaddr(conn->ksnc_sock, 0,
177 &conn->ksnc_myipaddr, NULL);
179 CERROR ("Error %d getting sock local IP\n", rc);
187 ksocknal_lib_sock_irq (struct socket *sock)
191 struct dst_entry *dst;
193 if (!*ksocknal_tunables.ksnd_irq_affinity)
196 dst = sk_dst_get (sock->sk);
198 if (dst->dev != NULL) {
200 if (irq >= NR_IRQS) {
201 CERROR ("Unexpected IRQ %x\n", irq);
213 ksocknal_lib_zc_capable(struct socket *sock)
215 int caps = sock->sk->sk_route_caps;
217 /* ZC if the socket supports scatter/gather and doesn't need software
219 return ((caps & NETIF_F_SG) != 0 &&
220 (caps & (NETIF_F_IP_CSUM | NETIF_F_NO_CSUM | NETIF_F_HW_CSUM)) != 0);
224 ksocknal_lib_send_iov (ksock_conn_t *conn, ksock_tx_t *tx)
226 struct socket *sock = conn->ksnc_sock;
230 if (*ksocknal_tunables.ksnd_enable_csum && /* checksum enabled */
231 conn->ksnc_proto == &ksocknal_protocol_v2x && /* V2.x connection */
232 tx->tx_nob == tx->tx_resid && /* frist sending */
233 tx->tx_msg.ksm_csum == 0) /* not checksummed */
234 ksocknal_lib_csum_tx(tx);
236 /* NB we can't trust socket ops to either consume our iovs
237 * or leave them alone. */
240 #if SOCKNAL_SINGLE_FRAG_TX
241 struct iovec scratch;
242 struct iovec *scratchiov = &scratch;
243 unsigned int niov = 1;
245 struct iovec *scratchiov = conn->ksnc_tx_scratch_iov;
246 unsigned int niov = tx->tx_niov;
248 struct msghdr msg = {
251 .msg_iov = scratchiov,
255 .msg_flags = MSG_DONTWAIT
257 mm_segment_t oldmm = get_fs();
260 for (nob = i = 0; i < niov; i++) {
261 scratchiov[i] = tx->tx_iov[i];
262 nob += scratchiov[i].iov_len;
265 if (!list_empty(&conn->ksnc_tx_queue) ||
267 msg.msg_flags |= MSG_MORE;
270 rc = sock_sendmsg(sock, &msg, nob);
277 ksocknal_lib_send_kiov (ksock_conn_t *conn, ksock_tx_t *tx)
279 struct socket *sock = conn->ksnc_sock;
280 lnet_kiov_t *kiov = tx->tx_kiov;
284 /* NB we can't trust socket ops to either consume our iovs
285 * or leave them alone. */
287 if (kiov->kiov_len >= *ksocknal_tunables.ksnd_zc_min_frag &&
288 tx->tx_msg.ksm_zc_req_cookie != 0) {
289 /* Zero copy is enabled */
290 struct page *page = kiov->kiov_page;
291 int offset = kiov->kiov_offset;
292 int fragsize = kiov->kiov_len;
293 int msgflg = MSG_DONTWAIT;
295 CDEBUG(D_NET, "page %p + offset %x for %d\n",
296 page, offset, kiov->kiov_len);
298 if (!list_empty(&conn->ksnc_tx_queue) ||
299 fragsize < tx->tx_resid)
302 rc = tcp_sendpage(sock, page, offset, fragsize, msgflg);
304 #if SOCKNAL_SINGLE_FRAG_TX || !SOCKNAL_RISK_KMAP_DEADLOCK
305 struct iovec scratch;
306 struct iovec *scratchiov = &scratch;
307 unsigned int niov = 1;
309 #ifdef CONFIG_HIGHMEM
310 #warning "XXX risk of kmap deadlock on multiple frags..."
312 struct iovec *scratchiov = conn->ksnc_tx_scratch_iov;
313 unsigned int niov = tx->tx_nkiov;
315 struct msghdr msg = {
318 .msg_iov = scratchiov,
322 .msg_flags = MSG_DONTWAIT
324 mm_segment_t oldmm = get_fs();
327 for (nob = i = 0; i < niov; i++) {
328 scratchiov[i].iov_base = kmap(kiov[i].kiov_page) +
330 nob += scratchiov[i].iov_len = kiov[i].kiov_len;
333 if (!list_empty(&conn->ksnc_tx_queue) ||
335 msg.msg_flags |= MSG_MORE;
338 rc = sock_sendmsg(sock, &msg, nob);
341 for (i = 0; i < niov; i++)
342 kunmap(kiov[i].kiov_page);
348 ksocknal_lib_eager_ack (ksock_conn_t *conn)
351 mm_segment_t oldmm = get_fs();
352 struct socket *sock = conn->ksnc_sock;
354 /* Remind the socket to ACK eagerly. If I don't, the socket might
355 * think I'm about to send something it could piggy-back the ACK
356 * on, introducing delay in completing zero-copy sends in my
360 sock->ops->setsockopt (sock, SOL_TCP, TCP_QUICKACK,
361 (char *)&opt, sizeof (opt));
366 ksocknal_lib_recv_iov (ksock_conn_t *conn)
368 #if SOCKNAL_SINGLE_FRAG_RX
369 struct iovec scratch;
370 struct iovec *scratchiov = &scratch;
371 unsigned int niov = 1;
373 struct iovec *scratchiov = conn->ksnc_rx_scratch_iov;
374 unsigned int niov = conn->ksnc_rx_niov;
376 struct iovec *iov = conn->ksnc_rx_iov;
377 struct msghdr msg = {
380 .msg_iov = scratchiov,
386 mm_segment_t oldmm = get_fs();
394 /* NB we can't trust socket ops to either consume our iovs
395 * or leave them alone. */
398 for (nob = i = 0; i < niov; i++) {
399 scratchiov[i] = iov[i];
400 nob += scratchiov[i].iov_len;
402 LASSERT (nob <= conn->ksnc_rx_nob_wanted);
405 rc = sock_recvmsg (conn->ksnc_sock, &msg, nob, MSG_DONTWAIT);
406 /* NB this is just a boolean..........................^ */
410 if (conn->ksnc_proto == &ksocknal_protocol_v2x) {
411 saved_csum = conn->ksnc_msg.ksm_csum;
412 conn->ksnc_msg.ksm_csum = 0;
415 if (saved_csum != 0) {
416 /* accumulate checksum */
417 for (i = 0, sum = rc; sum > 0; i++, sum -= fragnob) {
420 fragnob = iov[i].iov_len;
424 conn->ksnc_rx_csum = ksocknal_csum(conn->ksnc_rx_csum,
425 iov[i].iov_base, fragnob);
427 conn->ksnc_msg.ksm_csum = saved_csum;
434 ksocknal_lib_recv_kiov (ksock_conn_t *conn)
436 #if SOCKNAL_SINGLE_FRAG_RX || !SOCKNAL_RISK_KMAP_DEADLOCK
437 struct iovec scratch;
438 struct iovec *scratchiov = &scratch;
439 unsigned int niov = 1;
441 #ifdef CONFIG_HIGHMEM
442 #warning "XXX risk of kmap deadlock on multiple frags..."
444 struct iovec *scratchiov = conn->ksnc_rx_scratch_iov;
445 unsigned int niov = conn->ksnc_rx_nkiov;
447 lnet_kiov_t *kiov = conn->ksnc_rx_kiov;
448 struct msghdr msg = {
451 .msg_iov = scratchiov,
457 mm_segment_t oldmm = get_fs();
465 /* NB we can't trust socket ops to either consume our iovs
466 * or leave them alone. */
467 for (nob = i = 0; i < niov; i++) {
468 scratchiov[i].iov_base = kmap(kiov[i].kiov_page) + kiov[i].kiov_offset;
469 nob += scratchiov[i].iov_len = kiov[i].kiov_len;
471 LASSERT (nob <= conn->ksnc_rx_nob_wanted);
474 rc = sock_recvmsg (conn->ksnc_sock, &msg, nob, MSG_DONTWAIT);
475 /* NB this is just a boolean.......................^ */
478 if (conn->ksnc_msg.ksm_csum != 0) {
479 for (i = 0, sum = rc; sum > 0; i++, sum -= fragnob) {
482 /* Dang! have to kmap again because I have nowhere to stash the
483 * mapped address. But by doing it while the page is still
484 * mapped, the kernel just bumps the map count and returns me
485 * the address it stashed. */
486 base = kmap(kiov[i].kiov_page) + kiov[i].kiov_offset;
487 fragnob = kiov[i].kiov_len;
491 conn->ksnc_rx_csum = ksocknal_csum(conn->ksnc_rx_csum,
494 kunmap(kiov[i].kiov_page);
497 for (i = 0; i < niov; i++)
498 kunmap(kiov[i].kiov_page);
503 void ksocknal_lib_csum_tx(ksock_tx_t *tx)
509 LASSERT(tx->tx_iov[0].iov_base == (void *)&tx->tx_msg);
510 LASSERT(tx->tx_conn != NULL);
511 LASSERT(tx->tx_conn->ksnc_proto == &ksocknal_protocol_v2x);
513 tx->tx_msg.ksm_csum = 0;
515 csum = ksocknal_csum(~0, (void *)tx->tx_iov[0].iov_base,
516 tx->tx_iov[0].iov_len);
518 if (tx->tx_kiov != NULL) {
519 for (i = 0; i < tx->tx_nkiov; i++) {
520 base = kmap(tx->tx_kiov[i].kiov_page) +
521 tx->tx_kiov[i].kiov_offset;
523 csum = ksocknal_csum(csum, base, tx->tx_kiov[i].kiov_len);
525 kunmap(tx->tx_kiov[i].kiov_page);
528 for (i = 1; i < tx->tx_niov; i++)
529 csum = ksocknal_csum(csum, tx->tx_iov[i].iov_base,
530 tx->tx_iov[i].iov_len);
533 if (*ksocknal_tunables.ksnd_inject_csum_error) {
535 *ksocknal_tunables.ksnd_inject_csum_error = 0;
538 tx->tx_msg.ksm_csum = csum;
542 ksocknal_lib_get_conn_tunables (ksock_conn_t *conn, int *txmem, int *rxmem, int *nagle)
544 mm_segment_t oldmm = get_fs ();
545 struct socket *sock = conn->ksnc_sock;
549 rc = ksocknal_connsock_addref(conn);
551 LASSERT (conn->ksnc_closing);
552 *txmem = *rxmem = *nagle = 0;
556 rc = libcfs_sock_getbuf(sock, txmem, rxmem);
558 len = sizeof(*nagle);
560 rc = sock->ops->getsockopt(sock, SOL_TCP, TCP_NODELAY,
561 (char *)nagle, &len);
565 ksocknal_connsock_decref(conn);
570 *txmem = *rxmem = *nagle = 0;
576 ksocknal_lib_setup_sock (struct socket *sock)
578 mm_segment_t oldmm = get_fs ();
585 struct linger linger;
587 sock->sk->sk_allocation = GFP_NOFS;
589 /* Ensure this socket aborts active sends immediately when we close
596 rc = sock_setsockopt (sock, SOL_SOCKET, SO_LINGER,
597 (char *)&linger, sizeof (linger));
600 CERROR ("Can't set SO_LINGER: %d\n", rc);
606 rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_LINGER2,
607 (char *)&option, sizeof (option));
610 CERROR ("Can't set SO_LINGER2: %d\n", rc);
614 if (!*ksocknal_tunables.ksnd_nagle) {
618 rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_NODELAY,
619 (char *)&option, sizeof (option));
622 CERROR ("Can't disable nagle: %d\n", rc);
627 rc = libcfs_sock_setbuf(sock,
628 *ksocknal_tunables.ksnd_tx_buffer_size,
629 *ksocknal_tunables.ksnd_rx_buffer_size);
631 CERROR ("Can't set buffer tx %d, rx %d buffers: %d\n",
632 *ksocknal_tunables.ksnd_tx_buffer_size,
633 *ksocknal_tunables.ksnd_rx_buffer_size, rc);
637 /* TCP_BACKOFF_* sockopt tunables unsupported in stock kernels */
638 #ifdef SOCKNAL_BACKOFF
639 if (*ksocknal_tunables.ksnd_backoff_init > 0) {
640 option = *ksocknal_tunables.ksnd_backoff_init;
643 rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_BACKOFF_INIT,
644 (char *)&option, sizeof (option));
647 CERROR ("Can't set initial tcp backoff %d: %d\n",
653 if (*ksocknal_tunables.ksnd_backoff_max > 0) {
654 option = *ksocknal_tunables.ksnd_backoff_max;
657 rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_BACKOFF_MAX,
658 (char *)&option, sizeof (option));
661 CERROR ("Can't set maximum tcp backoff %d: %d\n",
668 /* snapshot tunables */
669 keep_idle = *ksocknal_tunables.ksnd_keepalive_idle;
670 keep_count = *ksocknal_tunables.ksnd_keepalive_count;
671 keep_intvl = *ksocknal_tunables.ksnd_keepalive_intvl;
673 do_keepalive = (keep_idle > 0 && keep_count > 0 && keep_intvl > 0);
675 option = (do_keepalive ? 1 : 0);
677 rc = sock_setsockopt (sock, SOL_SOCKET, SO_KEEPALIVE,
678 (char *)&option, sizeof (option));
681 CERROR ("Can't set SO_KEEPALIVE: %d\n", rc);
689 rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_KEEPIDLE,
690 (char *)&keep_idle, sizeof (keep_idle));
693 CERROR ("Can't set TCP_KEEPIDLE: %d\n", rc);
698 rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_KEEPINTVL,
699 (char *)&keep_intvl, sizeof (keep_intvl));
702 CERROR ("Can't set TCP_KEEPINTVL: %d\n", rc);
707 rc = sock->ops->setsockopt (sock, SOL_TCP, TCP_KEEPCNT,
708 (char *)&keep_count, sizeof (keep_count));
711 CERROR ("Can't set TCP_KEEPCNT: %d\n", rc);
718 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
719 struct tcp_opt *sock2tcp_opt(struct sock *sk)
721 return &(sk->tp_pinfo.af_tcp);
723 #elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,10))
724 #define sock2tcp_opt(sk) tcp_sk(sk)
726 struct tcp_opt *sock2tcp_opt(struct sock *sk)
728 struct tcp_sock *s = (struct tcp_sock *)sk;
734 ksocknal_lib_push_conn (ksock_conn_t *conn)
737 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,11))
747 rc = ksocknal_connsock_addref(conn);
748 if (rc != 0) /* being shut down */
751 sk = conn->ksnc_sock->sk;
752 tp = sock2tcp_opt(sk);
755 nonagle = tp->nonagle;
762 rc = sk->sk_prot->setsockopt (sk, SOL_TCP, TCP_NODELAY,
763 (char *)&val, sizeof (val));
769 tp->nonagle = nonagle;
772 ksocknal_connsock_decref(conn);
775 extern void ksocknal_read_callback (ksock_conn_t *conn);
776 extern void ksocknal_write_callback (ksock_conn_t *conn);
778 * socket call back in Linux
781 ksocknal_data_ready (struct sock *sk, int n)
786 /* interleave correctly with closing sockets... */
788 read_lock (&ksocknal_data.ksnd_global_lock);
790 conn = sk->sk_user_data;
791 if (conn == NULL) { /* raced with ksocknal_terminate_conn */
792 LASSERT (sk->sk_data_ready != &ksocknal_data_ready);
793 sk->sk_data_ready (sk, n);
795 ksocknal_read_callback(conn);
797 read_unlock (&ksocknal_data.ksnd_global_lock);
803 ksocknal_write_space (struct sock *sk)
809 /* interleave correctly with closing sockets... */
811 read_lock (&ksocknal_data.ksnd_global_lock);
813 conn = sk->sk_user_data;
814 wspace = SOCKNAL_WSPACE(sk);
815 min_wpace = SOCKNAL_MIN_WSPACE(sk);
817 CDEBUG(D_NET, "sk %p wspace %d low water %d conn %p%s%s%s\n",
818 sk, wspace, min_wpace, conn,
819 (conn == NULL) ? "" : (conn->ksnc_tx_ready ?
820 " ready" : " blocked"),
821 (conn == NULL) ? "" : (conn->ksnc_tx_scheduled ?
822 " scheduled" : " idle"),
823 (conn == NULL) ? "" : (list_empty (&conn->ksnc_tx_queue) ?
824 " empty" : " queued"));
826 if (conn == NULL) { /* raced with ksocknal_terminate_conn */
827 LASSERT (sk->sk_write_space != &ksocknal_write_space);
828 sk->sk_write_space (sk);
830 read_unlock (&ksocknal_data.ksnd_global_lock);
834 if (wspace >= min_wpace) { /* got enough space */
835 ksocknal_write_callback(conn);
837 /* Clear SOCK_NOSPACE _after_ ksocknal_write_callback so the
838 * ENOMEM check in ksocknal_transmit is race-free (think about
841 clear_bit (SOCK_NOSPACE, &sk->sk_socket->flags);
844 read_unlock (&ksocknal_data.ksnd_global_lock);
848 ksocknal_lib_save_callback(struct socket *sock, ksock_conn_t *conn)
850 conn->ksnc_saved_data_ready = sock->sk->sk_data_ready;
851 conn->ksnc_saved_write_space = sock->sk->sk_write_space;
855 ksocknal_lib_set_callback(struct socket *sock, ksock_conn_t *conn)
857 sock->sk->sk_user_data = conn;
858 sock->sk->sk_data_ready = ksocknal_data_ready;
859 sock->sk->sk_write_space = ksocknal_write_space;
864 ksocknal_lib_reset_callback(struct socket *sock, ksock_conn_t *conn)
866 /* Remove conn's network callbacks.
867 * NB I _have_ to restore the callback, rather than storing a noop,
868 * since the socket could survive past this module being unloaded!! */
869 sock->sk->sk_data_ready = conn->ksnc_saved_data_ready;
870 sock->sk->sk_write_space = conn->ksnc_saved_write_space;
872 /* A callback could be in progress already; they hold a read lock
873 * on ksnd_global_lock (to serialise with me) and NOOP if
874 * sk_user_data is NULL. */
875 sock->sk->sk_user_data = NULL;