blob: 990626e7da80aaf411c67f8e20ca73ac3a46bc0a [file] [log] [blame]
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001/******************************************************************************
2*******************************************************************************
3**
4** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06005** Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01006**
7** This copyrighted material is made available to anyone wishing to use,
8** modify, copy, or redistribute it subject to the terms and conditions
9** of the GNU General Public License v.2.
10**
11*******************************************************************************
12******************************************************************************/
13
14/*
15 * lowcomms.c
16 *
17 * This is the "low-level" comms layer.
18 *
19 * It is responsible for sending/receiving messages
20 * from other nodes in the cluster.
21 *
22 * Cluster nodes are referred to by their nodeids. nodeids are
23 * simply 32 bit numbers to the locking module - if they need to
Joe Perches2cf12c02009-01-22 13:26:47 -080024 * be expanded for the cluster infrastructure then that is its
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010025 * responsibility. It is this layer's
26 * responsibility to resolve these into IP address or
27 * whatever it needs for inter-node communication.
28 *
29 * The comms level is two kernel threads that deal mainly with
30 * the receiving of messages from other nodes and passing them
31 * up to the mid-level comms layer (which understands the
32 * message format) for execution by the locking core, and
33 * a send thread which does all the setting up of connections
34 * to remote nodes and the sending of data. Threads are not allowed
35 * to send their own data because it may cause them to wait in times
36 * of high load. Also, this way, the sending thread can collect together
37 * messages bound for one node and send them in one block.
38 *
Joe Perches2cf12c02009-01-22 13:26:47 -080039 * lowcomms will choose to use either TCP or SCTP as its transport layer
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010040 * depending on the configuration variable 'protocol'. This should be set
Joe Perches2cf12c02009-01-22 13:26:47 -080041 * to 0 (default) for TCP or 1 for SCTP. It should be configured using a
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010042 * cluster-wide mechanism as it must be the same on all nodes of the cluster
43 * for the DLM to function.
44 *
45 */
46
47#include <asm/ioctls.h>
48#include <net/sock.h>
49#include <net/tcp.h>
50#include <linux/pagemap.h>
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010051#include <linux/file.h>
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -050052#include <linux/mutex.h>
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010053#include <linux/sctp.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090054#include <linux/slab.h>
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010055#include <net/sctp/user.h>
Joe Perches44ad5322009-01-22 13:24:49 -080056#include <net/ipv6.h>
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010057
58#include "dlm_internal.h"
59#include "lowcomms.h"
60#include "midcomms.h"
61#include "config.h"
62
63#define NEEDED_RMEM (4*1024*1024)
Christine Caulfield5e9ccc32009-01-28 12:57:40 -060064#define CONN_HASH_SIZE 32
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010065
Bob Petersonf92c8dd2010-11-12 11:15:20 -060066/* Number of messages to send before rescheduling */
67#define MAX_SEND_MSG_COUNT 25
68
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010069struct cbuf {
70 unsigned int base;
71 unsigned int len;
72 unsigned int mask;
73};
74
75static void cbuf_add(struct cbuf *cb, int n)
76{
77 cb->len += n;
78}
79
80static int cbuf_data(struct cbuf *cb)
81{
82 return ((cb->base + cb->len) & cb->mask);
83}
84
85static void cbuf_init(struct cbuf *cb, int size)
86{
87 cb->base = cb->len = 0;
88 cb->mask = size-1;
89}
90
91static void cbuf_eat(struct cbuf *cb, int n)
92{
93 cb->len -= n;
94 cb->base += n;
95 cb->base &= cb->mask;
96}
97
98static bool cbuf_empty(struct cbuf *cb)
99{
100 return cb->len == 0;
101}
102
103struct connection {
104 struct socket *sock; /* NULL if not connected */
105 uint32_t nodeid; /* So we know who we are in the list */
106 struct mutex sock_mutex;
107 unsigned long flags;
108#define CF_READ_PENDING 1
109#define CF_WRITE_PENDING 2
110#define CF_CONNECT_PENDING 3
111#define CF_INIT_PENDING 4
112#define CF_IS_OTHERCON 5
Lars Marowsky-Bree063c4c92009-08-11 16:18:23 -0500113#define CF_CLOSE 6
David Millerb36930d2010-11-10 21:56:39 -0800114#define CF_APP_LIMITED 7
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100115 struct list_head writequeue; /* List of outgoing writequeue_entries */
116 spinlock_t writequeue_lock;
117 int (*rx_action) (struct connection *); /* What to do when active */
118 void (*connect_action) (struct connection *); /* What to do to connect */
119 struct page *rx_page;
120 struct cbuf cb;
121 int retries;
122#define MAX_CONNECT_RETRIES 3
123 int sctp_assoc;
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600124 struct hlist_node list;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100125 struct connection *othercon;
126 struct work_struct rwork; /* Receive workqueue */
127 struct work_struct swork; /* Send workqueue */
128};
129#define sock2con(x) ((struct connection *)(x)->sk_user_data)
130
131/* An entry waiting to be sent */
132struct writequeue_entry {
133 struct list_head list;
134 struct page *page;
135 int offset;
136 int len;
137 int end;
138 int users;
139 struct connection *con;
140};
141
142static struct sockaddr_storage *dlm_local_addr[DLM_MAX_ADDR_COUNT];
143static int dlm_local_count;
144
145/* Work queues */
146static struct workqueue_struct *recv_workqueue;
147static struct workqueue_struct *send_workqueue;
148
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600149static struct hlist_head connection_hash[CONN_HASH_SIZE];
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500150static DEFINE_MUTEX(connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100151static struct kmem_cache *con_cache;
152
153static void process_recv_sockets(struct work_struct *work);
154static void process_send_sockets(struct work_struct *work);
155
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600156
157/* This is deliberately very simple because most clusters have simple
158 sequential nodeids, so we should be able to go straight to a connection
159 struct in the array */
160static inline int nodeid_hash(int nodeid)
161{
162 return nodeid & (CONN_HASH_SIZE-1);
163}
164
165static struct connection *__find_con(int nodeid)
166{
167 int r;
168 struct hlist_node *h;
169 struct connection *con;
170
171 r = nodeid_hash(nodeid);
172
173 hlist_for_each_entry(con, h, &connection_hash[r], list) {
174 if (con->nodeid == nodeid)
175 return con;
176 }
177 return NULL;
178}
179
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100180/*
181 * If 'allocation' is zero then we don't attempt to create a new
182 * connection structure for this node.
183 */
184static struct connection *__nodeid2con(int nodeid, gfp_t alloc)
185{
186 struct connection *con = NULL;
187 int r;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100188
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600189 con = __find_con(nodeid);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100190 if (con || !alloc)
191 return con;
192
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100193 con = kmem_cache_zalloc(con_cache, alloc);
194 if (!con)
195 return NULL;
196
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600197 r = nodeid_hash(nodeid);
198 hlist_add_head(&con->list, &connection_hash[r]);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100199
200 con->nodeid = nodeid;
201 mutex_init(&con->sock_mutex);
202 INIT_LIST_HEAD(&con->writequeue);
203 spin_lock_init(&con->writequeue_lock);
204 INIT_WORK(&con->swork, process_send_sockets);
205 INIT_WORK(&con->rwork, process_recv_sockets);
206
207 /* Setup action pointers for child sockets */
208 if (con->nodeid) {
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600209 struct connection *zerocon = __find_con(0);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100210
211 con->connect_action = zerocon->connect_action;
212 if (!con->rx_action)
213 con->rx_action = zerocon->rx_action;
214 }
215
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100216 return con;
217}
218
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600219/* Loop round all connections */
220static void foreach_conn(void (*conn_func)(struct connection *c))
221{
222 int i;
223 struct hlist_node *h, *n;
224 struct connection *con;
225
226 for (i = 0; i < CONN_HASH_SIZE; i++) {
227 hlist_for_each_entry_safe(con, h, n, &connection_hash[i], list){
228 conn_func(con);
229 }
230 }
231}
232
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100233static struct connection *nodeid2con(int nodeid, gfp_t allocation)
234{
235 struct connection *con;
236
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500237 mutex_lock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100238 con = __nodeid2con(nodeid, allocation);
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500239 mutex_unlock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100240
241 return con;
242}
243
244/* This is a bit drastic, but only called when things go wrong */
245static struct connection *assoc2con(int assoc_id)
246{
247 int i;
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600248 struct hlist_node *h;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100249 struct connection *con;
250
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500251 mutex_lock(&connections_lock);
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600252
253 for (i = 0 ; i < CONN_HASH_SIZE; i++) {
254 hlist_for_each_entry(con, h, &connection_hash[i], list) {
Julia Lawallf70cb332010-08-03 23:34:16 +0200255 if (con->sctp_assoc == assoc_id) {
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600256 mutex_unlock(&connections_lock);
257 return con;
258 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100259 }
260 }
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500261 mutex_unlock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100262 return NULL;
263}
264
265static int nodeid_to_addr(int nodeid, struct sockaddr *retaddr)
266{
267 struct sockaddr_storage addr;
268 int error;
269
270 if (!dlm_local_count)
271 return -1;
272
273 error = dlm_nodeid_to_addr(nodeid, &addr);
274 if (error)
275 return error;
276
277 if (dlm_local_addr[0]->ss_family == AF_INET) {
278 struct sockaddr_in *in4 = (struct sockaddr_in *) &addr;
279 struct sockaddr_in *ret4 = (struct sockaddr_in *) retaddr;
280 ret4->sin_addr.s_addr = in4->sin_addr.s_addr;
281 } else {
282 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) &addr;
283 struct sockaddr_in6 *ret6 = (struct sockaddr_in6 *) retaddr;
Joe Perches44ad5322009-01-22 13:24:49 -0800284 ipv6_addr_copy(&ret6->sin6_addr, &in6->sin6_addr);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100285 }
286
287 return 0;
288}
289
290/* Data available on socket or listen socket received a connect */
291static void lowcomms_data_ready(struct sock *sk, int count_unused)
292{
293 struct connection *con = sock2con(sk);
Patrick Caulfieldafb853f2007-06-01 10:07:26 -0500294 if (con && !test_and_set_bit(CF_READ_PENDING, &con->flags))
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100295 queue_work(recv_workqueue, &con->rwork);
296}
297
298static void lowcomms_write_space(struct sock *sk)
299{
300 struct connection *con = sock2con(sk);
301
David Millerb36930d2010-11-10 21:56:39 -0800302 if (!con)
303 return;
304
305 clear_bit(SOCK_NOSPACE, &con->sock->flags);
306
307 if (test_and_clear_bit(CF_APP_LIMITED, &con->flags)) {
308 con->sock->sk->sk_write_pending--;
309 clear_bit(SOCK_ASYNC_NOSPACE, &con->sock->flags);
310 }
311
312 if (!test_and_set_bit(CF_WRITE_PENDING, &con->flags))
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100313 queue_work(send_workqueue, &con->swork);
314}
315
316static inline void lowcomms_connect_sock(struct connection *con)
317{
Lars Marowsky-Bree063c4c92009-08-11 16:18:23 -0500318 if (test_bit(CF_CLOSE, &con->flags))
319 return;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100320 if (!test_and_set_bit(CF_CONNECT_PENDING, &con->flags))
321 queue_work(send_workqueue, &con->swork);
322}
323
324static void lowcomms_state_change(struct sock *sk)
325{
326 if (sk->sk_state == TCP_ESTABLISHED)
327 lowcomms_write_space(sk);
328}
329
Christine Caulfield391fbdc2009-05-07 10:54:16 -0500330int dlm_lowcomms_connect_node(int nodeid)
331{
332 struct connection *con;
333
David Teigland04bedd72009-09-18 14:31:47 -0500334 /* with sctp there's no connecting without sending */
335 if (dlm_config.ci_protocol != 0)
336 return 0;
337
Christine Caulfield391fbdc2009-05-07 10:54:16 -0500338 if (nodeid == dlm_our_nodeid())
339 return 0;
340
341 con = nodeid2con(nodeid, GFP_NOFS);
342 if (!con)
343 return -ENOMEM;
344 lowcomms_connect_sock(con);
345 return 0;
346}
347
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100348/* Make a socket active */
349static int add_sock(struct socket *sock, struct connection *con)
350{
351 con->sock = sock;
352
353 /* Install a data_ready callback */
354 con->sock->sk->sk_data_ready = lowcomms_data_ready;
355 con->sock->sk->sk_write_space = lowcomms_write_space;
356 con->sock->sk->sk_state_change = lowcomms_state_change;
357 con->sock->sk->sk_user_data = con;
Steven Whitehoused6d7b702008-11-12 16:49:48 -0600358 con->sock->sk->sk_allocation = GFP_NOFS;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100359 return 0;
360}
361
362/* Add the port number to an IPv6 or 4 sockaddr and return the address
363 length */
364static void make_sockaddr(struct sockaddr_storage *saddr, uint16_t port,
365 int *addr_len)
366{
367 saddr->ss_family = dlm_local_addr[0]->ss_family;
368 if (saddr->ss_family == AF_INET) {
369 struct sockaddr_in *in4_addr = (struct sockaddr_in *)saddr;
370 in4_addr->sin_port = cpu_to_be16(port);
371 *addr_len = sizeof(struct sockaddr_in);
372 memset(&in4_addr->sin_zero, 0, sizeof(in4_addr->sin_zero));
373 } else {
374 struct sockaddr_in6 *in6_addr = (struct sockaddr_in6 *)saddr;
375 in6_addr->sin6_port = cpu_to_be16(port);
376 *addr_len = sizeof(struct sockaddr_in6);
377 }
Patrick Caulfield01c8cab2007-07-17 16:53:15 +0100378 memset((char *)saddr + *addr_len, 0, sizeof(struct sockaddr_storage) - *addr_len);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100379}
380
381/* Close a remote connection and tidy up */
382static void close_connection(struct connection *con, bool and_other)
383{
384 mutex_lock(&con->sock_mutex);
385
386 if (con->sock) {
387 sock_release(con->sock);
388 con->sock = NULL;
389 }
390 if (con->othercon && and_other) {
391 /* Will only re-enter once. */
392 close_connection(con->othercon, false);
393 }
394 if (con->rx_page) {
395 __free_page(con->rx_page);
396 con->rx_page = NULL;
397 }
Patrick Caulfield9e5f2822007-08-02 14:58:14 +0100398
Patrick Caulfield61d96be2007-08-20 15:13:38 +0100399 con->retries = 0;
400 mutex_unlock(&con->sock_mutex);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100401}
402
403/* We only send shutdown messages to nodes that are not part of the cluster */
404static void sctp_send_shutdown(sctp_assoc_t associd)
405{
406 static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
407 struct msghdr outmessage;
408 struct cmsghdr *cmsg;
409 struct sctp_sndrcvinfo *sinfo;
410 int ret;
411 struct connection *con;
412
413 con = nodeid2con(0,0);
414 BUG_ON(con == NULL);
415
416 outmessage.msg_name = NULL;
417 outmessage.msg_namelen = 0;
418 outmessage.msg_control = outcmsg;
419 outmessage.msg_controllen = sizeof(outcmsg);
420 outmessage.msg_flags = MSG_EOR;
421
422 cmsg = CMSG_FIRSTHDR(&outmessage);
423 cmsg->cmsg_level = IPPROTO_SCTP;
424 cmsg->cmsg_type = SCTP_SNDRCV;
425 cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo));
426 outmessage.msg_controllen = cmsg->cmsg_len;
427 sinfo = CMSG_DATA(cmsg);
428 memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo));
429
430 sinfo->sinfo_flags |= MSG_EOF;
431 sinfo->sinfo_assoc_id = associd;
432
433 ret = kernel_sendmsg(con->sock, &outmessage, NULL, 0, 0);
434
435 if (ret != 0)
436 log_print("send EOF to node failed: %d", ret);
437}
438
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600439static void sctp_init_failed_foreach(struct connection *con)
440{
441 con->sctp_assoc = 0;
442 if (test_and_clear_bit(CF_CONNECT_PENDING, &con->flags)) {
443 if (!test_and_set_bit(CF_WRITE_PENDING, &con->flags))
444 queue_work(send_workqueue, &con->swork);
445 }
446}
447
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100448/* INIT failed but we don't know which node...
449 restart INIT on all pending nodes */
450static void sctp_init_failed(void)
451{
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500452 mutex_lock(&connections_lock);
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600453
454 foreach_conn(sctp_init_failed_foreach);
455
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500456 mutex_unlock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100457}
458
459/* Something happened to an association */
David Teigland617e82e2007-04-26 13:46:49 -0500460static void process_sctp_notification(struct connection *con,
461 struct msghdr *msg, char *buf)
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100462{
463 union sctp_notification *sn = (union sctp_notification *)buf;
464
465 if (sn->sn_header.sn_type == SCTP_ASSOC_CHANGE) {
466 switch (sn->sn_assoc_change.sac_state) {
467
468 case SCTP_COMM_UP:
469 case SCTP_RESTART:
470 {
471 /* Check that the new node is in the lockspace */
472 struct sctp_prim prim;
473 int nodeid;
474 int prim_len, ret;
475 int addr_len;
476 struct connection *new_con;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100477 sctp_peeloff_arg_t parg;
478 int parglen = sizeof(parg);
David Teigland6861f352009-09-24 15:58:23 -0500479 int err;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100480
481 /*
482 * We get this before any data for an association.
483 * We verify that the node is in the cluster and
484 * then peel off a socket for it.
485 */
486 if ((int)sn->sn_assoc_change.sac_assoc_id <= 0) {
487 log_print("COMM_UP for invalid assoc ID %d",
David Teigland617e82e2007-04-26 13:46:49 -0500488 (int)sn->sn_assoc_change.sac_assoc_id);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100489 sctp_init_failed();
490 return;
491 }
492 memset(&prim, 0, sizeof(struct sctp_prim));
493 prim_len = sizeof(struct sctp_prim);
494 prim.ssp_assoc_id = sn->sn_assoc_change.sac_assoc_id;
495
496 ret = kernel_getsockopt(con->sock,
497 IPPROTO_SCTP,
498 SCTP_PRIMARY_ADDR,
499 (char*)&prim,
500 &prim_len);
501 if (ret < 0) {
502 log_print("getsockopt/sctp_primary_addr on "
503 "new assoc %d failed : %d",
504 (int)sn->sn_assoc_change.sac_assoc_id,
505 ret);
506
507 /* Retry INIT later */
508 new_con = assoc2con(sn->sn_assoc_change.sac_assoc_id);
509 if (new_con)
510 clear_bit(CF_CONNECT_PENDING, &con->flags);
511 return;
512 }
513 make_sockaddr(&prim.ssp_addr, 0, &addr_len);
514 if (dlm_addr_to_nodeid(&prim.ssp_addr, &nodeid)) {
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100515 unsigned char *b=(unsigned char *)&prim.ssp_addr;
516 log_print("reject connect from unknown addr");
Masatake YAMATObcaadf52011-07-04 12:25:51 +0900517 print_hex_dump_bytes("ss: ", DUMP_PREFIX_NONE,
518 b, sizeof(struct sockaddr_storage));
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100519 sctp_send_shutdown(prim.ssp_assoc_id);
520 return;
521 }
522
David Teigland748285c2009-05-15 10:50:57 -0500523 new_con = nodeid2con(nodeid, GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100524 if (!new_con)
525 return;
526
527 /* Peel off a new sock */
528 parg.associd = sn->sn_assoc_change.sac_assoc_id;
David Teigland617e82e2007-04-26 13:46:49 -0500529 ret = kernel_getsockopt(con->sock, IPPROTO_SCTP,
530 SCTP_SOCKOPT_PEELOFF,
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100531 (void *)&parg, &parglen);
David Teigland6861f352009-09-24 15:58:23 -0500532 if (ret < 0) {
David Teigland617e82e2007-04-26 13:46:49 -0500533 log_print("Can't peel off a socket for "
David Teigland6861f352009-09-24 15:58:23 -0500534 "connection %d to node %d: err=%d",
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100535 parg.associd, nodeid, ret);
David Teigland6861f352009-09-24 15:58:23 -0500536 return;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100537 }
David Teigland6861f352009-09-24 15:58:23 -0500538 new_con->sock = sockfd_lookup(parg.sd, &err);
539 if (!new_con->sock) {
540 log_print("sockfd_lookup error %d", err);
541 return;
542 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100543 add_sock(new_con->sock, new_con);
David Teigland6861f352009-09-24 15:58:23 -0500544 sockfd_put(new_con->sock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100545
David Teigland6861f352009-09-24 15:58:23 -0500546 log_print("connecting to %d sctp association %d",
547 nodeid, (int)sn->sn_assoc_change.sac_assoc_id);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100548
549 /* Send any pending writes */
550 clear_bit(CF_CONNECT_PENDING, &new_con->flags);
551 clear_bit(CF_INIT_PENDING, &con->flags);
552 if (!test_and_set_bit(CF_WRITE_PENDING, &new_con->flags)) {
553 queue_work(send_workqueue, &new_con->swork);
554 }
555 if (!test_and_set_bit(CF_READ_PENDING, &new_con->flags))
556 queue_work(recv_workqueue, &new_con->rwork);
557 }
558 break;
559
560 case SCTP_COMM_LOST:
561 case SCTP_SHUTDOWN_COMP:
562 {
563 con = assoc2con(sn->sn_assoc_change.sac_assoc_id);
564 if (con) {
565 con->sctp_assoc = 0;
566 }
567 }
568 break;
569
570 /* We don't know which INIT failed, so clear the PENDING flags
571 * on them all. if assoc_id is zero then it will then try
572 * again */
573
574 case SCTP_CANT_STR_ASSOC:
575 {
576 log_print("Can't start SCTP association - retrying");
577 sctp_init_failed();
578 }
579 break;
580
581 default:
582 log_print("unexpected SCTP assoc change id=%d state=%d",
583 (int)sn->sn_assoc_change.sac_assoc_id,
584 sn->sn_assoc_change.sac_state);
585 }
586 }
587}
588
589/* Data received from remote end */
590static int receive_from_sock(struct connection *con)
591{
592 int ret = 0;
593 struct msghdr msg = {};
594 struct kvec iov[2];
595 unsigned len;
596 int r;
597 int call_again_soon = 0;
598 int nvec;
599 char incmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
600
601 mutex_lock(&con->sock_mutex);
602
603 if (con->sock == NULL) {
604 ret = -EAGAIN;
605 goto out_close;
606 }
607
608 if (con->rx_page == NULL) {
609 /*
610 * This doesn't need to be atomic, but I think it should
611 * improve performance if it is.
612 */
613 con->rx_page = alloc_page(GFP_ATOMIC);
614 if (con->rx_page == NULL)
615 goto out_resched;
616 cbuf_init(&con->cb, PAGE_CACHE_SIZE);
617 }
618
619 /* Only SCTP needs these really */
620 memset(&incmsg, 0, sizeof(incmsg));
621 msg.msg_control = incmsg;
622 msg.msg_controllen = sizeof(incmsg);
623
624 /*
625 * iov[0] is the bit of the circular buffer between the current end
626 * point (cb.base + cb.len) and the end of the buffer.
627 */
628 iov[0].iov_len = con->cb.base - cbuf_data(&con->cb);
629 iov[0].iov_base = page_address(con->rx_page) + cbuf_data(&con->cb);
630 iov[1].iov_len = 0;
631 nvec = 1;
632
633 /*
634 * iov[1] is the bit of the circular buffer between the start of the
635 * buffer and the start of the currently used section (cb.base)
636 */
637 if (cbuf_data(&con->cb) >= con->cb.base) {
638 iov[0].iov_len = PAGE_CACHE_SIZE - cbuf_data(&con->cb);
639 iov[1].iov_len = con->cb.base;
640 iov[1].iov_base = page_address(con->rx_page);
641 nvec = 2;
642 }
643 len = iov[0].iov_len + iov[1].iov_len;
644
645 r = ret = kernel_recvmsg(con->sock, &msg, iov, nvec, len,
646 MSG_DONTWAIT | MSG_NOSIGNAL);
647 if (ret <= 0)
648 goto out_close;
649
650 /* Process SCTP notifications */
651 if (msg.msg_flags & MSG_NOTIFICATION) {
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100652 msg.msg_control = incmsg;
653 msg.msg_controllen = sizeof(incmsg);
654
655 process_sctp_notification(con, &msg,
David Teigland617e82e2007-04-26 13:46:49 -0500656 page_address(con->rx_page) + con->cb.base);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100657 mutex_unlock(&con->sock_mutex);
658 return 0;
659 }
660 BUG_ON(con->nodeid == 0);
661
662 if (ret == len)
663 call_again_soon = 1;
664 cbuf_add(&con->cb, ret);
665 ret = dlm_process_incoming_buffer(con->nodeid,
666 page_address(con->rx_page),
667 con->cb.base, con->cb.len,
668 PAGE_CACHE_SIZE);
669 if (ret == -EBADMSG) {
David Teigland617e82e2007-04-26 13:46:49 -0500670 log_print("lowcomms: addr=%p, base=%u, len=%u, "
671 "iov_len=%u, iov_base[0]=%p, read=%d",
672 page_address(con->rx_page), con->cb.base, con->cb.len,
673 len, iov[0].iov_base, r);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100674 }
675 if (ret < 0)
676 goto out_close;
677 cbuf_eat(&con->cb, ret);
678
679 if (cbuf_empty(&con->cb) && !call_again_soon) {
680 __free_page(con->rx_page);
681 con->rx_page = NULL;
682 }
683
684 if (call_again_soon)
685 goto out_resched;
686 mutex_unlock(&con->sock_mutex);
687 return 0;
688
689out_resched:
690 if (!test_and_set_bit(CF_READ_PENDING, &con->flags))
691 queue_work(recv_workqueue, &con->rwork);
692 mutex_unlock(&con->sock_mutex);
693 return -EAGAIN;
694
695out_close:
696 mutex_unlock(&con->sock_mutex);
Patrick Caulfield9e5f2822007-08-02 14:58:14 +0100697 if (ret != -EAGAIN) {
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100698 close_connection(con, false);
699 /* Reconnect when there is something to send */
700 }
701 /* Don't return success if we really got EOF */
702 if (ret == 0)
703 ret = -EAGAIN;
704
705 return ret;
706}
707
708/* Listening socket is busy, accept a connection */
709static int tcp_accept_from_sock(struct connection *con)
710{
711 int result;
712 struct sockaddr_storage peeraddr;
713 struct socket *newsock;
714 int len;
715 int nodeid;
716 struct connection *newcon;
717 struct connection *addcon;
718
719 memset(&peeraddr, 0, sizeof(peeraddr));
720 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_STREAM,
721 IPPROTO_TCP, &newsock);
722 if (result < 0)
723 return -ENOMEM;
724
725 mutex_lock_nested(&con->sock_mutex, 0);
726
727 result = -ENOTCONN;
728 if (con->sock == NULL)
729 goto accept_err;
730
731 newsock->type = con->sock->type;
732 newsock->ops = con->sock->ops;
733
734 result = con->sock->ops->accept(con->sock, newsock, O_NONBLOCK);
735 if (result < 0)
736 goto accept_err;
737
738 /* Get the connected socket's peer */
739 memset(&peeraddr, 0, sizeof(peeraddr));
740 if (newsock->ops->getname(newsock, (struct sockaddr *)&peeraddr,
741 &len, 2)) {
742 result = -ECONNABORTED;
743 goto accept_err;
744 }
745
746 /* Get the new node's NODEID */
747 make_sockaddr(&peeraddr, 0, &len);
748 if (dlm_addr_to_nodeid(&peeraddr, &nodeid)) {
Masatake YAMATObcaadf52011-07-04 12:25:51 +0900749 unsigned char *b=(unsigned char *)&peeraddr;
David Teigland617e82e2007-04-26 13:46:49 -0500750 log_print("connect from non cluster node");
Masatake YAMATObcaadf52011-07-04 12:25:51 +0900751 print_hex_dump_bytes("ss: ", DUMP_PREFIX_NONE,
752 b, sizeof(struct sockaddr_storage));
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100753 sock_release(newsock);
754 mutex_unlock(&con->sock_mutex);
755 return -1;
756 }
757
758 log_print("got connection from %d", nodeid);
759
760 /* Check to see if we already have a connection to this node. This
761 * could happen if the two nodes initiate a connection at roughly
762 * the same time and the connections cross on the wire.
763 * In this case we store the incoming one in "othercon"
764 */
David Teigland748285c2009-05-15 10:50:57 -0500765 newcon = nodeid2con(nodeid, GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100766 if (!newcon) {
767 result = -ENOMEM;
768 goto accept_err;
769 }
770 mutex_lock_nested(&newcon->sock_mutex, 1);
771 if (newcon->sock) {
772 struct connection *othercon = newcon->othercon;
773
774 if (!othercon) {
David Teigland748285c2009-05-15 10:50:57 -0500775 othercon = kmem_cache_zalloc(con_cache, GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100776 if (!othercon) {
David Teigland617e82e2007-04-26 13:46:49 -0500777 log_print("failed to allocate incoming socket");
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100778 mutex_unlock(&newcon->sock_mutex);
779 result = -ENOMEM;
780 goto accept_err;
781 }
782 othercon->nodeid = nodeid;
783 othercon->rx_action = receive_from_sock;
784 mutex_init(&othercon->sock_mutex);
785 INIT_WORK(&othercon->swork, process_send_sockets);
786 INIT_WORK(&othercon->rwork, process_recv_sockets);
787 set_bit(CF_IS_OTHERCON, &othercon->flags);
Patrick Caulfield61d96be2007-08-20 15:13:38 +0100788 }
789 if (!othercon->sock) {
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100790 newcon->othercon = othercon;
Patrick Caulfield97d84832007-06-27 11:36:23 +0100791 othercon->sock = newsock;
792 newsock->sk->sk_user_data = othercon;
793 add_sock(newsock, othercon);
794 addcon = othercon;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100795 }
Patrick Caulfield97d84832007-06-27 11:36:23 +0100796 else {
797 printk("Extra connection from node %d attempted\n", nodeid);
798 result = -EAGAIN;
akpm@linux-foundation.orgf4fadb23c2007-06-27 14:43:37 -0700799 mutex_unlock(&newcon->sock_mutex);
Patrick Caulfield97d84832007-06-27 11:36:23 +0100800 goto accept_err;
801 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100802 }
803 else {
804 newsock->sk->sk_user_data = newcon;
805 newcon->rx_action = receive_from_sock;
806 add_sock(newsock, newcon);
807 addcon = newcon;
808 }
809
810 mutex_unlock(&newcon->sock_mutex);
811
812 /*
813 * Add it to the active queue in case we got data
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300814 * between processing the accept adding the socket
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100815 * to the read_sockets list
816 */
817 if (!test_and_set_bit(CF_READ_PENDING, &addcon->flags))
818 queue_work(recv_workqueue, &addcon->rwork);
819 mutex_unlock(&con->sock_mutex);
820
821 return 0;
822
823accept_err:
824 mutex_unlock(&con->sock_mutex);
825 sock_release(newsock);
826
827 if (result != -EAGAIN)
David Teigland617e82e2007-04-26 13:46:49 -0500828 log_print("error accepting connection from node: %d", result);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100829 return result;
830}
831
832static void free_entry(struct writequeue_entry *e)
833{
834 __free_page(e->page);
835 kfree(e);
836}
837
838/* Initiate an SCTP association.
839 This is a special case of send_to_sock() in that we don't yet have a
840 peeled-off socket for this association, so we use the listening socket
841 and add the primary IP address of the remote node.
842 */
843static void sctp_init_assoc(struct connection *con)
844{
845 struct sockaddr_storage rem_addr;
846 char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
847 struct msghdr outmessage;
848 struct cmsghdr *cmsg;
849 struct sctp_sndrcvinfo *sinfo;
850 struct connection *base_con;
851 struct writequeue_entry *e;
852 int len, offset;
853 int ret;
854 int addrlen;
855 struct kvec iov[1];
856
857 if (test_and_set_bit(CF_INIT_PENDING, &con->flags))
858 return;
859
860 if (con->retries++ > MAX_CONNECT_RETRIES)
861 return;
862
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100863 if (nodeid_to_addr(con->nodeid, (struct sockaddr *)&rem_addr)) {
864 log_print("no address for nodeid %d", con->nodeid);
865 return;
866 }
867 base_con = nodeid2con(0, 0);
868 BUG_ON(base_con == NULL);
869
870 make_sockaddr(&rem_addr, dlm_config.ci_tcp_port, &addrlen);
871
872 outmessage.msg_name = &rem_addr;
873 outmessage.msg_namelen = addrlen;
874 outmessage.msg_control = outcmsg;
875 outmessage.msg_controllen = sizeof(outcmsg);
876 outmessage.msg_flags = MSG_EOR;
877
878 spin_lock(&con->writequeue_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100879
David Teigland04bedd72009-09-18 14:31:47 -0500880 if (list_empty(&con->writequeue)) {
881 spin_unlock(&con->writequeue_lock);
882 log_print("writequeue empty for nodeid %d", con->nodeid);
883 return;
884 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100885
David Teigland04bedd72009-09-18 14:31:47 -0500886 e = list_first_entry(&con->writequeue, struct writequeue_entry, list);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100887 len = e->len;
888 offset = e->offset;
889 spin_unlock(&con->writequeue_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100890
891 /* Send the first block off the write queue */
892 iov[0].iov_base = page_address(e->page)+offset;
893 iov[0].iov_len = len;
894
895 cmsg = CMSG_FIRSTHDR(&outmessage);
896 cmsg->cmsg_level = IPPROTO_SCTP;
897 cmsg->cmsg_type = SCTP_SNDRCV;
898 cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo));
899 sinfo = CMSG_DATA(cmsg);
900 memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo));
901 sinfo->sinfo_ppid = cpu_to_le32(dlm_our_nodeid());
902 outmessage.msg_controllen = cmsg->cmsg_len;
903
904 ret = kernel_sendmsg(base_con->sock, &outmessage, iov, 1, len);
905 if (ret < 0) {
David Teigland617e82e2007-04-26 13:46:49 -0500906 log_print("Send first packet to node %d failed: %d",
907 con->nodeid, ret);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100908
909 /* Try again later */
910 clear_bit(CF_CONNECT_PENDING, &con->flags);
911 clear_bit(CF_INIT_PENDING, &con->flags);
912 }
913 else {
914 spin_lock(&con->writequeue_lock);
915 e->offset += ret;
916 e->len -= ret;
917
918 if (e->len == 0 && e->users == 0) {
919 list_del(&e->list);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100920 free_entry(e);
921 }
922 spin_unlock(&con->writequeue_lock);
923 }
924}
925
926/* Connect a new socket to its peer */
927static void tcp_connect_to_sock(struct connection *con)
928{
929 int result = -EHOSTUNREACH;
Lon Hohberger6bd8fed2007-10-25 18:51:54 -0400930 struct sockaddr_storage saddr, src_addr;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100931 int addr_len;
Casey Dahlina89d63a2009-07-14 12:17:51 -0500932 struct socket *sock = NULL;
David Teiglandcb2d45d2010-11-12 11:12:55 -0600933 int one = 1;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100934
935 if (con->nodeid == 0) {
936 log_print("attempt to connect sock 0 foiled");
937 return;
938 }
939
940 mutex_lock(&con->sock_mutex);
941 if (con->retries++ > MAX_CONNECT_RETRIES)
942 goto out;
943
944 /* Some odd races can cause double-connects, ignore them */
945 if (con->sock) {
946 result = 0;
947 goto out;
948 }
949
950 /* Create a socket to communicate with */
951 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_STREAM,
952 IPPROTO_TCP, &sock);
953 if (result < 0)
954 goto out_err;
955
956 memset(&saddr, 0, sizeof(saddr));
Casey Dahlinb5711b82009-07-28 12:29:05 -0500957 if (dlm_nodeid_to_addr(con->nodeid, &saddr))
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100958 goto out_err;
959
960 sock->sk->sk_user_data = con;
961 con->rx_action = receive_from_sock;
962 con->connect_action = tcp_connect_to_sock;
963 add_sock(sock, con);
964
Lon Hohberger6bd8fed2007-10-25 18:51:54 -0400965 /* Bind to our cluster-known address connecting to avoid
966 routing problems */
967 memcpy(&src_addr, dlm_local_addr[0], sizeof(src_addr));
968 make_sockaddr(&src_addr, 0, &addr_len);
969 result = sock->ops->bind(sock, (struct sockaddr *) &src_addr,
970 addr_len);
971 if (result < 0) {
972 log_print("could not bind for connect: %d", result);
973 /* This *may* not indicate a critical error */
974 }
975
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100976 make_sockaddr(&saddr, dlm_config.ci_tcp_port, &addr_len);
977
978 log_print("connecting to %d", con->nodeid);
David Teiglandcb2d45d2010-11-12 11:12:55 -0600979
980 /* Turn off Nagle's algorithm */
981 kernel_setsockopt(sock, SOL_TCP, TCP_NODELAY, (char *)&one,
982 sizeof(one));
983
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100984 result =
985 sock->ops->connect(sock, (struct sockaddr *)&saddr, addr_len,
986 O_NONBLOCK);
987 if (result == -EINPROGRESS)
988 result = 0;
989 if (result == 0)
990 goto out;
991
992out_err:
993 if (con->sock) {
994 sock_release(con->sock);
995 con->sock = NULL;
Casey Dahlina89d63a2009-07-14 12:17:51 -0500996 } else if (sock) {
997 sock_release(sock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100998 }
999 /*
1000 * Some errors are fatal and this list might need adjusting. For other
1001 * errors we try again until the max number of retries is reached.
1002 */
1003 if (result != -EHOSTUNREACH && result != -ENETUNREACH &&
Marcin Slusarz0035a4b2008-05-11 22:01:29 +02001004 result != -ENETDOWN && result != -EINVAL
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001005 && result != -EPROTONOSUPPORT) {
1006 lowcomms_connect_sock(con);
1007 result = 0;
1008 }
1009out:
1010 mutex_unlock(&con->sock_mutex);
1011 return;
1012}
1013
1014static struct socket *tcp_create_listen_sock(struct connection *con,
1015 struct sockaddr_storage *saddr)
1016{
1017 struct socket *sock = NULL;
1018 int result = 0;
1019 int one = 1;
1020 int addr_len;
1021
1022 if (dlm_local_addr[0]->ss_family == AF_INET)
1023 addr_len = sizeof(struct sockaddr_in);
1024 else
1025 addr_len = sizeof(struct sockaddr_in6);
1026
1027 /* Create a socket to communicate with */
David Teigland617e82e2007-04-26 13:46:49 -05001028 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_STREAM,
1029 IPPROTO_TCP, &sock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001030 if (result < 0) {
David Teigland617e82e2007-04-26 13:46:49 -05001031 log_print("Can't create listening comms socket");
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001032 goto create_out;
1033 }
1034
David Teiglandcb2d45d2010-11-12 11:12:55 -06001035 /* Turn off Nagle's algorithm */
1036 kernel_setsockopt(sock, SOL_TCP, TCP_NODELAY, (char *)&one,
1037 sizeof(one));
1038
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001039 result = kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
1040 (char *)&one, sizeof(one));
1041
1042 if (result < 0) {
David Teigland617e82e2007-04-26 13:46:49 -05001043 log_print("Failed to set SO_REUSEADDR on socket: %d", result);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001044 }
1045 sock->sk->sk_user_data = con;
1046 con->rx_action = tcp_accept_from_sock;
1047 con->connect_action = tcp_connect_to_sock;
1048 con->sock = sock;
1049
1050 /* Bind to our port */
1051 make_sockaddr(saddr, dlm_config.ci_tcp_port, &addr_len);
1052 result = sock->ops->bind(sock, (struct sockaddr *) saddr, addr_len);
1053 if (result < 0) {
David Teigland617e82e2007-04-26 13:46:49 -05001054 log_print("Can't bind to port %d", dlm_config.ci_tcp_port);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001055 sock_release(sock);
1056 sock = NULL;
1057 con->sock = NULL;
1058 goto create_out;
1059 }
1060 result = kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
1061 (char *)&one, sizeof(one));
1062 if (result < 0) {
David Teigland617e82e2007-04-26 13:46:49 -05001063 log_print("Set keepalive failed: %d", result);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001064 }
1065
1066 result = sock->ops->listen(sock, 5);
1067 if (result < 0) {
David Teigland617e82e2007-04-26 13:46:49 -05001068 log_print("Can't listen on port %d", dlm_config.ci_tcp_port);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001069 sock_release(sock);
1070 sock = NULL;
1071 goto create_out;
1072 }
1073
1074create_out:
1075 return sock;
1076}
1077
1078/* Get local addresses */
1079static void init_local(void)
1080{
1081 struct sockaddr_storage sas, *addr;
1082 int i;
1083
Patrick Caulfield30d3a232007-04-23 16:26:21 +01001084 dlm_local_count = 0;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001085 for (i = 0; i < DLM_MAX_ADDR_COUNT - 1; i++) {
1086 if (dlm_our_addr(&sas, i))
1087 break;
1088
David Teigland573c24c2009-11-30 16:34:43 -06001089 addr = kmalloc(sizeof(*addr), GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001090 if (!addr)
1091 break;
1092 memcpy(addr, &sas, sizeof(*addr));
1093 dlm_local_addr[dlm_local_count++] = addr;
1094 }
1095}
1096
David Teigland617e82e2007-04-26 13:46:49 -05001097/* Bind to an IP address. SCTP allows multiple address so it can do
1098 multi-homing */
1099static int add_sctp_bind_addr(struct connection *sctp_con,
1100 struct sockaddr_storage *addr,
1101 int addr_len, int num)
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001102{
1103 int result = 0;
1104
1105 if (num == 1)
1106 result = kernel_bind(sctp_con->sock,
1107 (struct sockaddr *) addr,
1108 addr_len);
1109 else
1110 result = kernel_setsockopt(sctp_con->sock, SOL_SCTP,
1111 SCTP_SOCKOPT_BINDX_ADD,
1112 (char *)addr, addr_len);
1113
1114 if (result < 0)
1115 log_print("Can't bind to port %d addr number %d",
1116 dlm_config.ci_tcp_port, num);
1117
1118 return result;
1119}
1120
1121/* Initialise SCTP socket and bind to all interfaces */
1122static int sctp_listen_for_all(void)
1123{
1124 struct socket *sock = NULL;
1125 struct sockaddr_storage localaddr;
1126 struct sctp_event_subscribe subscribe;
1127 int result = -EINVAL, num = 1, i, addr_len;
David Teigland573c24c2009-11-30 16:34:43 -06001128 struct connection *con = nodeid2con(0, GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001129 int bufsize = NEEDED_RMEM;
1130
1131 if (!con)
1132 return -ENOMEM;
1133
1134 log_print("Using SCTP for communications");
1135
1136 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_SEQPACKET,
1137 IPPROTO_SCTP, &sock);
1138 if (result < 0) {
1139 log_print("Can't create comms socket, check SCTP is loaded");
1140 goto out;
1141 }
1142
1143 /* Listen for events */
1144 memset(&subscribe, 0, sizeof(subscribe));
1145 subscribe.sctp_data_io_event = 1;
1146 subscribe.sctp_association_event = 1;
1147 subscribe.sctp_send_failure_event = 1;
1148 subscribe.sctp_shutdown_event = 1;
1149 subscribe.sctp_partial_delivery_event = 1;
1150
David S. Millerdf61c952007-11-06 23:48:57 -08001151 result = kernel_setsockopt(sock, SOL_SOCKET, SO_RCVBUFFORCE,
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001152 (char *)&bufsize, sizeof(bufsize));
1153 if (result)
David Teigland617e82e2007-04-26 13:46:49 -05001154 log_print("Error increasing buffer space on socket %d", result);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001155
1156 result = kernel_setsockopt(sock, SOL_SCTP, SCTP_EVENTS,
David Teigland617e82e2007-04-26 13:46:49 -05001157 (char *)&subscribe, sizeof(subscribe));
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001158 if (result < 0) {
1159 log_print("Failed to set SCTP_EVENTS on socket: result=%d",
1160 result);
1161 goto create_delsock;
1162 }
1163
1164 /* Init con struct */
1165 sock->sk->sk_user_data = con;
1166 con->sock = sock;
1167 con->sock->sk->sk_data_ready = lowcomms_data_ready;
1168 con->rx_action = receive_from_sock;
1169 con->connect_action = sctp_init_assoc;
1170
1171 /* Bind to all interfaces. */
1172 for (i = 0; i < dlm_local_count; i++) {
1173 memcpy(&localaddr, dlm_local_addr[i], sizeof(localaddr));
1174 make_sockaddr(&localaddr, dlm_config.ci_tcp_port, &addr_len);
1175
1176 result = add_sctp_bind_addr(con, &localaddr, addr_len, num);
1177 if (result)
1178 goto create_delsock;
1179 ++num;
1180 }
1181
1182 result = sock->ops->listen(sock, 5);
1183 if (result < 0) {
1184 log_print("Can't set socket listening");
1185 goto create_delsock;
1186 }
1187
1188 return 0;
1189
1190create_delsock:
1191 sock_release(sock);
1192 con->sock = NULL;
1193out:
1194 return result;
1195}
1196
1197static int tcp_listen_for_all(void)
1198{
1199 struct socket *sock = NULL;
David Teigland573c24c2009-11-30 16:34:43 -06001200 struct connection *con = nodeid2con(0, GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001201 int result = -EINVAL;
1202
1203 if (!con)
1204 return -ENOMEM;
1205
1206 /* We don't support multi-homed hosts */
1207 if (dlm_local_addr[1] != NULL) {
David Teigland617e82e2007-04-26 13:46:49 -05001208 log_print("TCP protocol can't handle multi-homed hosts, "
1209 "try SCTP");
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001210 return -EINVAL;
1211 }
1212
1213 log_print("Using TCP for communications");
1214
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001215 sock = tcp_create_listen_sock(con, dlm_local_addr[0]);
1216 if (sock) {
1217 add_sock(sock, con);
1218 result = 0;
1219 }
1220 else {
1221 result = -EADDRINUSE;
1222 }
1223
1224 return result;
1225}
1226
1227
1228
1229static struct writequeue_entry *new_writequeue_entry(struct connection *con,
1230 gfp_t allocation)
1231{
1232 struct writequeue_entry *entry;
1233
1234 entry = kmalloc(sizeof(struct writequeue_entry), allocation);
1235 if (!entry)
1236 return NULL;
1237
1238 entry->page = alloc_page(allocation);
1239 if (!entry->page) {
1240 kfree(entry);
1241 return NULL;
1242 }
1243
1244 entry->offset = 0;
1245 entry->len = 0;
1246 entry->end = 0;
1247 entry->users = 0;
1248 entry->con = con;
1249
1250 return entry;
1251}
1252
David Teigland617e82e2007-04-26 13:46:49 -05001253void *dlm_lowcomms_get_buffer(int nodeid, int len, gfp_t allocation, char **ppc)
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001254{
1255 struct connection *con;
1256 struct writequeue_entry *e;
1257 int offset = 0;
1258 int users = 0;
1259
1260 con = nodeid2con(nodeid, allocation);
1261 if (!con)
1262 return NULL;
1263
1264 spin_lock(&con->writequeue_lock);
1265 e = list_entry(con->writequeue.prev, struct writequeue_entry, list);
1266 if ((&e->list == &con->writequeue) ||
1267 (PAGE_CACHE_SIZE - e->end < len)) {
1268 e = NULL;
1269 } else {
1270 offset = e->end;
1271 e->end += len;
1272 users = e->users++;
1273 }
1274 spin_unlock(&con->writequeue_lock);
1275
1276 if (e) {
1277 got_one:
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001278 *ppc = page_address(e->page) + offset;
1279 return e;
1280 }
1281
1282 e = new_writequeue_entry(con, allocation);
1283 if (e) {
1284 spin_lock(&con->writequeue_lock);
1285 offset = e->end;
1286 e->end += len;
1287 users = e->users++;
1288 list_add_tail(&e->list, &con->writequeue);
1289 spin_unlock(&con->writequeue_lock);
1290 goto got_one;
1291 }
1292 return NULL;
1293}
1294
1295void dlm_lowcomms_commit_buffer(void *mh)
1296{
1297 struct writequeue_entry *e = (struct writequeue_entry *)mh;
1298 struct connection *con = e->con;
1299 int users;
1300
1301 spin_lock(&con->writequeue_lock);
1302 users = --e->users;
1303 if (users)
1304 goto out;
1305 e->len = e->end - e->offset;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001306 spin_unlock(&con->writequeue_lock);
1307
1308 if (!test_and_set_bit(CF_WRITE_PENDING, &con->flags)) {
1309 queue_work(send_workqueue, &con->swork);
1310 }
1311 return;
1312
1313out:
1314 spin_unlock(&con->writequeue_lock);
1315 return;
1316}
1317
1318/* Send a message */
1319static void send_to_sock(struct connection *con)
1320{
1321 int ret = 0;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001322 const int msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL;
1323 struct writequeue_entry *e;
1324 int len, offset;
Bob Petersonf92c8dd2010-11-12 11:15:20 -06001325 int count = 0;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001326
1327 mutex_lock(&con->sock_mutex);
1328 if (con->sock == NULL)
1329 goto out_connect;
1330
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001331 spin_lock(&con->writequeue_lock);
1332 for (;;) {
1333 e = list_entry(con->writequeue.next, struct writequeue_entry,
1334 list);
1335 if ((struct list_head *) e == &con->writequeue)
1336 break;
1337
1338 len = e->len;
1339 offset = e->offset;
1340 BUG_ON(len == 0 && e->users == 0);
1341 spin_unlock(&con->writequeue_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001342
1343 ret = 0;
1344 if (len) {
Paolo Bonzini1329e3f2009-08-24 13:18:04 -05001345 ret = kernel_sendpage(con->sock, e->page, offset, len,
1346 msg_flags);
Patrick Caulfieldd66f8272007-09-14 08:49:21 +01001347 if (ret == -EAGAIN || ret == 0) {
David Millerb36930d2010-11-10 21:56:39 -08001348 if (ret == -EAGAIN &&
1349 test_bit(SOCK_ASYNC_NOSPACE, &con->sock->flags) &&
1350 !test_and_set_bit(CF_APP_LIMITED, &con->flags)) {
1351 /* Notify TCP that we're limited by the
1352 * application window size.
1353 */
1354 set_bit(SOCK_NOSPACE, &con->sock->flags);
1355 con->sock->sk->sk_write_pending++;
1356 }
Patrick Caulfieldd66f8272007-09-14 08:49:21 +01001357 cond_resched();
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001358 goto out;
Patrick Caulfieldd66f8272007-09-14 08:49:21 +01001359 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001360 if (ret <= 0)
1361 goto send_error;
Patrick Caulfieldd66f8272007-09-14 08:49:21 +01001362 }
Bob Petersonf92c8dd2010-11-12 11:15:20 -06001363
1364 /* Don't starve people filling buffers */
1365 if (++count >= MAX_SEND_MSG_COUNT) {
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001366 cond_resched();
Bob Petersonf92c8dd2010-11-12 11:15:20 -06001367 count = 0;
1368 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001369
1370 spin_lock(&con->writequeue_lock);
1371 e->offset += ret;
1372 e->len -= ret;
1373
1374 if (e->len == 0 && e->users == 0) {
1375 list_del(&e->list);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001376 free_entry(e);
1377 continue;
1378 }
1379 }
1380 spin_unlock(&con->writequeue_lock);
1381out:
1382 mutex_unlock(&con->sock_mutex);
1383 return;
1384
1385send_error:
1386 mutex_unlock(&con->sock_mutex);
1387 close_connection(con, false);
1388 lowcomms_connect_sock(con);
1389 return;
1390
1391out_connect:
1392 mutex_unlock(&con->sock_mutex);
1393 if (!test_bit(CF_INIT_PENDING, &con->flags))
1394 lowcomms_connect_sock(con);
1395 return;
1396}
1397
1398static void clean_one_writequeue(struct connection *con)
1399{
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001400 struct writequeue_entry *e, *safe;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001401
1402 spin_lock(&con->writequeue_lock);
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001403 list_for_each_entry_safe(e, safe, &con->writequeue, list) {
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001404 list_del(&e->list);
1405 free_entry(e);
1406 }
1407 spin_unlock(&con->writequeue_lock);
1408}
1409
1410/* Called from recovery when it knows that a node has
1411 left the cluster */
1412int dlm_lowcomms_close(int nodeid)
1413{
1414 struct connection *con;
1415
1416 log_print("closing connection to node %d", nodeid);
1417 con = nodeid2con(nodeid, 0);
1418 if (con) {
Lars Marowsky-Bree063c4c92009-08-11 16:18:23 -05001419 clear_bit(CF_CONNECT_PENDING, &con->flags);
1420 clear_bit(CF_WRITE_PENDING, &con->flags);
1421 set_bit(CF_CLOSE, &con->flags);
1422 if (cancel_work_sync(&con->swork))
1423 log_print("canceled swork for node %d", nodeid);
1424 if (cancel_work_sync(&con->rwork))
1425 log_print("canceled rwork for node %d", nodeid);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001426 clean_one_writequeue(con);
1427 close_connection(con, true);
1428 }
1429 return 0;
1430}
1431
1432/* Receive workqueue function */
1433static void process_recv_sockets(struct work_struct *work)
1434{
1435 struct connection *con = container_of(work, struct connection, rwork);
1436 int err;
1437
1438 clear_bit(CF_READ_PENDING, &con->flags);
1439 do {
1440 err = con->rx_action(con);
1441 } while (!err);
1442}
1443
1444/* Send workqueue function */
1445static void process_send_sockets(struct work_struct *work)
1446{
1447 struct connection *con = container_of(work, struct connection, swork);
1448
1449 if (test_and_clear_bit(CF_CONNECT_PENDING, &con->flags)) {
1450 con->connect_action(con);
Lars Marowsky-Bree063c4c92009-08-11 16:18:23 -05001451 set_bit(CF_WRITE_PENDING, &con->flags);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001452 }
Lars Marowsky-Bree063c4c92009-08-11 16:18:23 -05001453 if (test_and_clear_bit(CF_WRITE_PENDING, &con->flags))
1454 send_to_sock(con);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001455}
1456
1457
1458/* Discard all entries on the write queues */
1459static void clean_writequeues(void)
1460{
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001461 foreach_conn(clean_one_writequeue);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001462}
1463
1464static void work_stop(void)
1465{
1466 destroy_workqueue(recv_workqueue);
1467 destroy_workqueue(send_workqueue);
1468}
1469
1470static int work_start(void)
1471{
David Teiglande43f0552011-03-10 13:22:34 -06001472 recv_workqueue = alloc_workqueue("dlm_recv",
1473 WQ_UNBOUND | WQ_MEM_RECLAIM, 1);
Namhyung Kimb9d41052010-12-13 13:42:24 -06001474 if (!recv_workqueue) {
1475 log_print("can't start dlm_recv");
1476 return -ENOMEM;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001477 }
1478
David Teiglande43f0552011-03-10 13:22:34 -06001479 send_workqueue = alloc_workqueue("dlm_send",
1480 WQ_UNBOUND | WQ_MEM_RECLAIM, 1);
Namhyung Kimb9d41052010-12-13 13:42:24 -06001481 if (!send_workqueue) {
1482 log_print("can't start dlm_send");
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001483 destroy_workqueue(recv_workqueue);
Namhyung Kimb9d41052010-12-13 13:42:24 -06001484 return -ENOMEM;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001485 }
1486
1487 return 0;
1488}
1489
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001490static void stop_conn(struct connection *con)
1491{
1492 con->flags |= 0x0F;
Christine Caulfield391fbdc2009-05-07 10:54:16 -05001493 if (con->sock && con->sock->sk)
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001494 con->sock->sk->sk_user_data = NULL;
1495}
1496
1497static void free_conn(struct connection *con)
1498{
1499 close_connection(con, true);
1500 if (con->othercon)
1501 kmem_cache_free(con_cache, con->othercon);
1502 hlist_del(&con->list);
1503 kmem_cache_free(con_cache, con);
1504}
1505
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001506void dlm_lowcomms_stop(void)
1507{
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001508 /* Set all the flags to prevent any
1509 socket activity.
1510 */
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -05001511 mutex_lock(&connections_lock);
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001512 foreach_conn(stop_conn);
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -05001513 mutex_unlock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001514
1515 work_stop();
1516
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -05001517 mutex_lock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001518 clean_writequeues();
1519
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001520 foreach_conn(free_conn);
1521
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -05001522 mutex_unlock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001523 kmem_cache_destroy(con_cache);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001524}
1525
1526int dlm_lowcomms_start(void)
1527{
1528 int error = -EINVAL;
1529 struct connection *con;
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001530 int i;
1531
1532 for (i = 0; i < CONN_HASH_SIZE; i++)
1533 INIT_HLIST_HEAD(&connection_hash[i]);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001534
1535 init_local();
1536 if (!dlm_local_count) {
David Teigland617e82e2007-04-26 13:46:49 -05001537 error = -ENOTCONN;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001538 log_print("no local IP address has been set");
1539 goto out;
1540 }
1541
1542 error = -ENOMEM;
1543 con_cache = kmem_cache_create("dlm_conn", sizeof(struct connection),
1544 __alignof__(struct connection), 0,
Paul Mundt20c2df82007-07-20 10:11:58 +09001545 NULL);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001546 if (!con_cache)
1547 goto out;
1548
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001549 /* Start listening */
1550 if (dlm_config.ci_protocol == 0)
1551 error = tcp_listen_for_all();
1552 else
1553 error = sctp_listen_for_all();
1554 if (error)
1555 goto fail_unlisten;
1556
1557 error = work_start();
1558 if (error)
1559 goto fail_unlisten;
1560
1561 return 0;
1562
1563fail_unlisten:
1564 con = nodeid2con(0,0);
1565 if (con) {
1566 close_connection(con, false);
1567 kmem_cache_free(con_cache, con);
1568 }
1569 kmem_cache_destroy(con_cache);
1570
1571out:
1572 return error;
1573}