blob: 52cab160893ce0d095e771dd1abe72a4b170162f [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>
54#include <net/sctp/user.h>
Joe Perches44ad5322009-01-22 13:24:49 -080055#include <net/ipv6.h>
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010056
57#include "dlm_internal.h"
58#include "lowcomms.h"
59#include "midcomms.h"
60#include "config.h"
61
62#define NEEDED_RMEM (4*1024*1024)
Christine Caulfield5e9ccc32009-01-28 12:57:40 -060063#define CONN_HASH_SIZE 32
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +010064
65struct cbuf {
66 unsigned int base;
67 unsigned int len;
68 unsigned int mask;
69};
70
71static void cbuf_add(struct cbuf *cb, int n)
72{
73 cb->len += n;
74}
75
76static int cbuf_data(struct cbuf *cb)
77{
78 return ((cb->base + cb->len) & cb->mask);
79}
80
81static void cbuf_init(struct cbuf *cb, int size)
82{
83 cb->base = cb->len = 0;
84 cb->mask = size-1;
85}
86
87static void cbuf_eat(struct cbuf *cb, int n)
88{
89 cb->len -= n;
90 cb->base += n;
91 cb->base &= cb->mask;
92}
93
94static bool cbuf_empty(struct cbuf *cb)
95{
96 return cb->len == 0;
97}
98
99struct connection {
100 struct socket *sock; /* NULL if not connected */
101 uint32_t nodeid; /* So we know who we are in the list */
102 struct mutex sock_mutex;
103 unsigned long flags;
104#define CF_READ_PENDING 1
105#define CF_WRITE_PENDING 2
106#define CF_CONNECT_PENDING 3
107#define CF_INIT_PENDING 4
108#define CF_IS_OTHERCON 5
Lars Marowsky-Bree063c4c92009-08-11 16:18:23 -0500109#define CF_CLOSE 6
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100110 struct list_head writequeue; /* List of outgoing writequeue_entries */
111 spinlock_t writequeue_lock;
112 int (*rx_action) (struct connection *); /* What to do when active */
113 void (*connect_action) (struct connection *); /* What to do to connect */
114 struct page *rx_page;
115 struct cbuf cb;
116 int retries;
117#define MAX_CONNECT_RETRIES 3
118 int sctp_assoc;
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600119 struct hlist_node list;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100120 struct connection *othercon;
121 struct work_struct rwork; /* Receive workqueue */
122 struct work_struct swork; /* Send workqueue */
123};
124#define sock2con(x) ((struct connection *)(x)->sk_user_data)
125
126/* An entry waiting to be sent */
127struct writequeue_entry {
128 struct list_head list;
129 struct page *page;
130 int offset;
131 int len;
132 int end;
133 int users;
134 struct connection *con;
135};
136
137static struct sockaddr_storage *dlm_local_addr[DLM_MAX_ADDR_COUNT];
138static int dlm_local_count;
139
140/* Work queues */
141static struct workqueue_struct *recv_workqueue;
142static struct workqueue_struct *send_workqueue;
143
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600144static struct hlist_head connection_hash[CONN_HASH_SIZE];
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500145static DEFINE_MUTEX(connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100146static struct kmem_cache *con_cache;
147
148static void process_recv_sockets(struct work_struct *work);
149static void process_send_sockets(struct work_struct *work);
150
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600151
152/* This is deliberately very simple because most clusters have simple
153 sequential nodeids, so we should be able to go straight to a connection
154 struct in the array */
155static inline int nodeid_hash(int nodeid)
156{
157 return nodeid & (CONN_HASH_SIZE-1);
158}
159
160static struct connection *__find_con(int nodeid)
161{
162 int r;
163 struct hlist_node *h;
164 struct connection *con;
165
166 r = nodeid_hash(nodeid);
167
168 hlist_for_each_entry(con, h, &connection_hash[r], list) {
169 if (con->nodeid == nodeid)
170 return con;
171 }
172 return NULL;
173}
174
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100175/*
176 * If 'allocation' is zero then we don't attempt to create a new
177 * connection structure for this node.
178 */
179static struct connection *__nodeid2con(int nodeid, gfp_t alloc)
180{
181 struct connection *con = NULL;
182 int r;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100183
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600184 con = __find_con(nodeid);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100185 if (con || !alloc)
186 return con;
187
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100188 con = kmem_cache_zalloc(con_cache, alloc);
189 if (!con)
190 return NULL;
191
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600192 r = nodeid_hash(nodeid);
193 hlist_add_head(&con->list, &connection_hash[r]);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100194
195 con->nodeid = nodeid;
196 mutex_init(&con->sock_mutex);
197 INIT_LIST_HEAD(&con->writequeue);
198 spin_lock_init(&con->writequeue_lock);
199 INIT_WORK(&con->swork, process_send_sockets);
200 INIT_WORK(&con->rwork, process_recv_sockets);
201
202 /* Setup action pointers for child sockets */
203 if (con->nodeid) {
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600204 struct connection *zerocon = __find_con(0);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100205
206 con->connect_action = zerocon->connect_action;
207 if (!con->rx_action)
208 con->rx_action = zerocon->rx_action;
209 }
210
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100211 return con;
212}
213
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600214/* Loop round all connections */
215static void foreach_conn(void (*conn_func)(struct connection *c))
216{
217 int i;
218 struct hlist_node *h, *n;
219 struct connection *con;
220
221 for (i = 0; i < CONN_HASH_SIZE; i++) {
222 hlist_for_each_entry_safe(con, h, n, &connection_hash[i], list){
223 conn_func(con);
224 }
225 }
226}
227
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100228static struct connection *nodeid2con(int nodeid, gfp_t allocation)
229{
230 struct connection *con;
231
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500232 mutex_lock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100233 con = __nodeid2con(nodeid, allocation);
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500234 mutex_unlock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100235
236 return con;
237}
238
239/* This is a bit drastic, but only called when things go wrong */
240static struct connection *assoc2con(int assoc_id)
241{
242 int i;
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600243 struct hlist_node *h;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100244 struct connection *con;
245
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500246 mutex_lock(&connections_lock);
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600247
248 for (i = 0 ; i < CONN_HASH_SIZE; i++) {
249 hlist_for_each_entry(con, h, &connection_hash[i], list) {
250 if (con && con->sctp_assoc == assoc_id) {
251 mutex_unlock(&connections_lock);
252 return con;
253 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100254 }
255 }
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500256 mutex_unlock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100257 return NULL;
258}
259
260static int nodeid_to_addr(int nodeid, struct sockaddr *retaddr)
261{
262 struct sockaddr_storage addr;
263 int error;
264
265 if (!dlm_local_count)
266 return -1;
267
268 error = dlm_nodeid_to_addr(nodeid, &addr);
269 if (error)
270 return error;
271
272 if (dlm_local_addr[0]->ss_family == AF_INET) {
273 struct sockaddr_in *in4 = (struct sockaddr_in *) &addr;
274 struct sockaddr_in *ret4 = (struct sockaddr_in *) retaddr;
275 ret4->sin_addr.s_addr = in4->sin_addr.s_addr;
276 } else {
277 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) &addr;
278 struct sockaddr_in6 *ret6 = (struct sockaddr_in6 *) retaddr;
Joe Perches44ad5322009-01-22 13:24:49 -0800279 ipv6_addr_copy(&ret6->sin6_addr, &in6->sin6_addr);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100280 }
281
282 return 0;
283}
284
285/* Data available on socket or listen socket received a connect */
286static void lowcomms_data_ready(struct sock *sk, int count_unused)
287{
288 struct connection *con = sock2con(sk);
Patrick Caulfieldafb853f2007-06-01 10:07:26 -0500289 if (con && !test_and_set_bit(CF_READ_PENDING, &con->flags))
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100290 queue_work(recv_workqueue, &con->rwork);
291}
292
293static void lowcomms_write_space(struct sock *sk)
294{
295 struct connection *con = sock2con(sk);
296
Patrick Caulfieldafb853f2007-06-01 10:07:26 -0500297 if (con && !test_and_set_bit(CF_WRITE_PENDING, &con->flags))
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100298 queue_work(send_workqueue, &con->swork);
299}
300
301static inline void lowcomms_connect_sock(struct connection *con)
302{
Lars Marowsky-Bree063c4c92009-08-11 16:18:23 -0500303 if (test_bit(CF_CLOSE, &con->flags))
304 return;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100305 if (!test_and_set_bit(CF_CONNECT_PENDING, &con->flags))
306 queue_work(send_workqueue, &con->swork);
307}
308
309static void lowcomms_state_change(struct sock *sk)
310{
311 if (sk->sk_state == TCP_ESTABLISHED)
312 lowcomms_write_space(sk);
313}
314
Christine Caulfield391fbdc2009-05-07 10:54:16 -0500315int dlm_lowcomms_connect_node(int nodeid)
316{
317 struct connection *con;
318
David Teigland04bedd72009-09-18 14:31:47 -0500319 /* with sctp there's no connecting without sending */
320 if (dlm_config.ci_protocol != 0)
321 return 0;
322
Christine Caulfield391fbdc2009-05-07 10:54:16 -0500323 if (nodeid == dlm_our_nodeid())
324 return 0;
325
326 con = nodeid2con(nodeid, GFP_NOFS);
327 if (!con)
328 return -ENOMEM;
329 lowcomms_connect_sock(con);
330 return 0;
331}
332
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100333/* Make a socket active */
334static int add_sock(struct socket *sock, struct connection *con)
335{
336 con->sock = sock;
337
338 /* Install a data_ready callback */
339 con->sock->sk->sk_data_ready = lowcomms_data_ready;
340 con->sock->sk->sk_write_space = lowcomms_write_space;
341 con->sock->sk->sk_state_change = lowcomms_state_change;
342 con->sock->sk->sk_user_data = con;
Steven Whitehoused6d7b702008-11-12 16:49:48 -0600343 con->sock->sk->sk_allocation = GFP_NOFS;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100344 return 0;
345}
346
347/* Add the port number to an IPv6 or 4 sockaddr and return the address
348 length */
349static void make_sockaddr(struct sockaddr_storage *saddr, uint16_t port,
350 int *addr_len)
351{
352 saddr->ss_family = dlm_local_addr[0]->ss_family;
353 if (saddr->ss_family == AF_INET) {
354 struct sockaddr_in *in4_addr = (struct sockaddr_in *)saddr;
355 in4_addr->sin_port = cpu_to_be16(port);
356 *addr_len = sizeof(struct sockaddr_in);
357 memset(&in4_addr->sin_zero, 0, sizeof(in4_addr->sin_zero));
358 } else {
359 struct sockaddr_in6 *in6_addr = (struct sockaddr_in6 *)saddr;
360 in6_addr->sin6_port = cpu_to_be16(port);
361 *addr_len = sizeof(struct sockaddr_in6);
362 }
Patrick Caulfield01c8cab2007-07-17 16:53:15 +0100363 memset((char *)saddr + *addr_len, 0, sizeof(struct sockaddr_storage) - *addr_len);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100364}
365
366/* Close a remote connection and tidy up */
367static void close_connection(struct connection *con, bool and_other)
368{
369 mutex_lock(&con->sock_mutex);
370
371 if (con->sock) {
372 sock_release(con->sock);
373 con->sock = NULL;
374 }
375 if (con->othercon && and_other) {
376 /* Will only re-enter once. */
377 close_connection(con->othercon, false);
378 }
379 if (con->rx_page) {
380 __free_page(con->rx_page);
381 con->rx_page = NULL;
382 }
Patrick Caulfield9e5f2822007-08-02 14:58:14 +0100383
Patrick Caulfield61d96be2007-08-20 15:13:38 +0100384 con->retries = 0;
385 mutex_unlock(&con->sock_mutex);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100386}
387
388/* We only send shutdown messages to nodes that are not part of the cluster */
389static void sctp_send_shutdown(sctp_assoc_t associd)
390{
391 static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
392 struct msghdr outmessage;
393 struct cmsghdr *cmsg;
394 struct sctp_sndrcvinfo *sinfo;
395 int ret;
396 struct connection *con;
397
398 con = nodeid2con(0,0);
399 BUG_ON(con == NULL);
400
401 outmessage.msg_name = NULL;
402 outmessage.msg_namelen = 0;
403 outmessage.msg_control = outcmsg;
404 outmessage.msg_controllen = sizeof(outcmsg);
405 outmessage.msg_flags = MSG_EOR;
406
407 cmsg = CMSG_FIRSTHDR(&outmessage);
408 cmsg->cmsg_level = IPPROTO_SCTP;
409 cmsg->cmsg_type = SCTP_SNDRCV;
410 cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo));
411 outmessage.msg_controllen = cmsg->cmsg_len;
412 sinfo = CMSG_DATA(cmsg);
413 memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo));
414
415 sinfo->sinfo_flags |= MSG_EOF;
416 sinfo->sinfo_assoc_id = associd;
417
418 ret = kernel_sendmsg(con->sock, &outmessage, NULL, 0, 0);
419
420 if (ret != 0)
421 log_print("send EOF to node failed: %d", ret);
422}
423
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600424static void sctp_init_failed_foreach(struct connection *con)
425{
426 con->sctp_assoc = 0;
427 if (test_and_clear_bit(CF_CONNECT_PENDING, &con->flags)) {
428 if (!test_and_set_bit(CF_WRITE_PENDING, &con->flags))
429 queue_work(send_workqueue, &con->swork);
430 }
431}
432
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100433/* INIT failed but we don't know which node...
434 restart INIT on all pending nodes */
435static void sctp_init_failed(void)
436{
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500437 mutex_lock(&connections_lock);
Christine Caulfield5e9ccc32009-01-28 12:57:40 -0600438
439 foreach_conn(sctp_init_failed_foreach);
440
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -0500441 mutex_unlock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100442}
443
444/* Something happened to an association */
David Teigland617e82e2007-04-26 13:46:49 -0500445static void process_sctp_notification(struct connection *con,
446 struct msghdr *msg, char *buf)
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100447{
448 union sctp_notification *sn = (union sctp_notification *)buf;
449
450 if (sn->sn_header.sn_type == SCTP_ASSOC_CHANGE) {
451 switch (sn->sn_assoc_change.sac_state) {
452
453 case SCTP_COMM_UP:
454 case SCTP_RESTART:
455 {
456 /* Check that the new node is in the lockspace */
457 struct sctp_prim prim;
458 int nodeid;
459 int prim_len, ret;
460 int addr_len;
461 struct connection *new_con;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100462 sctp_peeloff_arg_t parg;
463 int parglen = sizeof(parg);
David Teigland6861f352009-09-24 15:58:23 -0500464 int err;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100465
466 /*
467 * We get this before any data for an association.
468 * We verify that the node is in the cluster and
469 * then peel off a socket for it.
470 */
471 if ((int)sn->sn_assoc_change.sac_assoc_id <= 0) {
472 log_print("COMM_UP for invalid assoc ID %d",
David Teigland617e82e2007-04-26 13:46:49 -0500473 (int)sn->sn_assoc_change.sac_assoc_id);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100474 sctp_init_failed();
475 return;
476 }
477 memset(&prim, 0, sizeof(struct sctp_prim));
478 prim_len = sizeof(struct sctp_prim);
479 prim.ssp_assoc_id = sn->sn_assoc_change.sac_assoc_id;
480
481 ret = kernel_getsockopt(con->sock,
482 IPPROTO_SCTP,
483 SCTP_PRIMARY_ADDR,
484 (char*)&prim,
485 &prim_len);
486 if (ret < 0) {
487 log_print("getsockopt/sctp_primary_addr on "
488 "new assoc %d failed : %d",
489 (int)sn->sn_assoc_change.sac_assoc_id,
490 ret);
491
492 /* Retry INIT later */
493 new_con = assoc2con(sn->sn_assoc_change.sac_assoc_id);
494 if (new_con)
495 clear_bit(CF_CONNECT_PENDING, &con->flags);
496 return;
497 }
498 make_sockaddr(&prim.ssp_addr, 0, &addr_len);
499 if (dlm_addr_to_nodeid(&prim.ssp_addr, &nodeid)) {
500 int i;
501 unsigned char *b=(unsigned char *)&prim.ssp_addr;
502 log_print("reject connect from unknown addr");
503 for (i=0; i<sizeof(struct sockaddr_storage);i++)
504 printk("%02x ", b[i]);
505 printk("\n");
506 sctp_send_shutdown(prim.ssp_assoc_id);
507 return;
508 }
509
David Teigland748285c2009-05-15 10:50:57 -0500510 new_con = nodeid2con(nodeid, GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100511 if (!new_con)
512 return;
513
514 /* Peel off a new sock */
515 parg.associd = sn->sn_assoc_change.sac_assoc_id;
David Teigland617e82e2007-04-26 13:46:49 -0500516 ret = kernel_getsockopt(con->sock, IPPROTO_SCTP,
517 SCTP_SOCKOPT_PEELOFF,
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100518 (void *)&parg, &parglen);
David Teigland6861f352009-09-24 15:58:23 -0500519 if (ret < 0) {
David Teigland617e82e2007-04-26 13:46:49 -0500520 log_print("Can't peel off a socket for "
David Teigland6861f352009-09-24 15:58:23 -0500521 "connection %d to node %d: err=%d",
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100522 parg.associd, nodeid, ret);
David Teigland6861f352009-09-24 15:58:23 -0500523 return;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100524 }
David Teigland6861f352009-09-24 15:58:23 -0500525 new_con->sock = sockfd_lookup(parg.sd, &err);
526 if (!new_con->sock) {
527 log_print("sockfd_lookup error %d", err);
528 return;
529 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100530 add_sock(new_con->sock, new_con);
David Teigland6861f352009-09-24 15:58:23 -0500531 sockfd_put(new_con->sock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100532
David Teigland6861f352009-09-24 15:58:23 -0500533 log_print("connecting to %d sctp association %d",
534 nodeid, (int)sn->sn_assoc_change.sac_assoc_id);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100535
536 /* Send any pending writes */
537 clear_bit(CF_CONNECT_PENDING, &new_con->flags);
538 clear_bit(CF_INIT_PENDING, &con->flags);
539 if (!test_and_set_bit(CF_WRITE_PENDING, &new_con->flags)) {
540 queue_work(send_workqueue, &new_con->swork);
541 }
542 if (!test_and_set_bit(CF_READ_PENDING, &new_con->flags))
543 queue_work(recv_workqueue, &new_con->rwork);
544 }
545 break;
546
547 case SCTP_COMM_LOST:
548 case SCTP_SHUTDOWN_COMP:
549 {
550 con = assoc2con(sn->sn_assoc_change.sac_assoc_id);
551 if (con) {
552 con->sctp_assoc = 0;
553 }
554 }
555 break;
556
557 /* We don't know which INIT failed, so clear the PENDING flags
558 * on them all. if assoc_id is zero then it will then try
559 * again */
560
561 case SCTP_CANT_STR_ASSOC:
562 {
563 log_print("Can't start SCTP association - retrying");
564 sctp_init_failed();
565 }
566 break;
567
568 default:
569 log_print("unexpected SCTP assoc change id=%d state=%d",
570 (int)sn->sn_assoc_change.sac_assoc_id,
571 sn->sn_assoc_change.sac_state);
572 }
573 }
574}
575
576/* Data received from remote end */
577static int receive_from_sock(struct connection *con)
578{
579 int ret = 0;
580 struct msghdr msg = {};
581 struct kvec iov[2];
582 unsigned len;
583 int r;
584 int call_again_soon = 0;
585 int nvec;
586 char incmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
587
588 mutex_lock(&con->sock_mutex);
589
590 if (con->sock == NULL) {
591 ret = -EAGAIN;
592 goto out_close;
593 }
594
595 if (con->rx_page == NULL) {
596 /*
597 * This doesn't need to be atomic, but I think it should
598 * improve performance if it is.
599 */
600 con->rx_page = alloc_page(GFP_ATOMIC);
601 if (con->rx_page == NULL)
602 goto out_resched;
603 cbuf_init(&con->cb, PAGE_CACHE_SIZE);
604 }
605
606 /* Only SCTP needs these really */
607 memset(&incmsg, 0, sizeof(incmsg));
608 msg.msg_control = incmsg;
609 msg.msg_controllen = sizeof(incmsg);
610
611 /*
612 * iov[0] is the bit of the circular buffer between the current end
613 * point (cb.base + cb.len) and the end of the buffer.
614 */
615 iov[0].iov_len = con->cb.base - cbuf_data(&con->cb);
616 iov[0].iov_base = page_address(con->rx_page) + cbuf_data(&con->cb);
617 iov[1].iov_len = 0;
618 nvec = 1;
619
620 /*
621 * iov[1] is the bit of the circular buffer between the start of the
622 * buffer and the start of the currently used section (cb.base)
623 */
624 if (cbuf_data(&con->cb) >= con->cb.base) {
625 iov[0].iov_len = PAGE_CACHE_SIZE - cbuf_data(&con->cb);
626 iov[1].iov_len = con->cb.base;
627 iov[1].iov_base = page_address(con->rx_page);
628 nvec = 2;
629 }
630 len = iov[0].iov_len + iov[1].iov_len;
631
632 r = ret = kernel_recvmsg(con->sock, &msg, iov, nvec, len,
633 MSG_DONTWAIT | MSG_NOSIGNAL);
634 if (ret <= 0)
635 goto out_close;
636
637 /* Process SCTP notifications */
638 if (msg.msg_flags & MSG_NOTIFICATION) {
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100639 msg.msg_control = incmsg;
640 msg.msg_controllen = sizeof(incmsg);
641
642 process_sctp_notification(con, &msg,
David Teigland617e82e2007-04-26 13:46:49 -0500643 page_address(con->rx_page) + con->cb.base);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100644 mutex_unlock(&con->sock_mutex);
645 return 0;
646 }
647 BUG_ON(con->nodeid == 0);
648
649 if (ret == len)
650 call_again_soon = 1;
651 cbuf_add(&con->cb, ret);
652 ret = dlm_process_incoming_buffer(con->nodeid,
653 page_address(con->rx_page),
654 con->cb.base, con->cb.len,
655 PAGE_CACHE_SIZE);
656 if (ret == -EBADMSG) {
David Teigland617e82e2007-04-26 13:46:49 -0500657 log_print("lowcomms: addr=%p, base=%u, len=%u, "
658 "iov_len=%u, iov_base[0]=%p, read=%d",
659 page_address(con->rx_page), con->cb.base, con->cb.len,
660 len, iov[0].iov_base, r);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100661 }
662 if (ret < 0)
663 goto out_close;
664 cbuf_eat(&con->cb, ret);
665
666 if (cbuf_empty(&con->cb) && !call_again_soon) {
667 __free_page(con->rx_page);
668 con->rx_page = NULL;
669 }
670
671 if (call_again_soon)
672 goto out_resched;
673 mutex_unlock(&con->sock_mutex);
674 return 0;
675
676out_resched:
677 if (!test_and_set_bit(CF_READ_PENDING, &con->flags))
678 queue_work(recv_workqueue, &con->rwork);
679 mutex_unlock(&con->sock_mutex);
680 return -EAGAIN;
681
682out_close:
683 mutex_unlock(&con->sock_mutex);
Patrick Caulfield9e5f2822007-08-02 14:58:14 +0100684 if (ret != -EAGAIN) {
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100685 close_connection(con, false);
686 /* Reconnect when there is something to send */
687 }
688 /* Don't return success if we really got EOF */
689 if (ret == 0)
690 ret = -EAGAIN;
691
692 return ret;
693}
694
695/* Listening socket is busy, accept a connection */
696static int tcp_accept_from_sock(struct connection *con)
697{
698 int result;
699 struct sockaddr_storage peeraddr;
700 struct socket *newsock;
701 int len;
702 int nodeid;
703 struct connection *newcon;
704 struct connection *addcon;
705
706 memset(&peeraddr, 0, sizeof(peeraddr));
707 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_STREAM,
708 IPPROTO_TCP, &newsock);
709 if (result < 0)
710 return -ENOMEM;
711
712 mutex_lock_nested(&con->sock_mutex, 0);
713
714 result = -ENOTCONN;
715 if (con->sock == NULL)
716 goto accept_err;
717
718 newsock->type = con->sock->type;
719 newsock->ops = con->sock->ops;
720
721 result = con->sock->ops->accept(con->sock, newsock, O_NONBLOCK);
722 if (result < 0)
723 goto accept_err;
724
725 /* Get the connected socket's peer */
726 memset(&peeraddr, 0, sizeof(peeraddr));
727 if (newsock->ops->getname(newsock, (struct sockaddr *)&peeraddr,
728 &len, 2)) {
729 result = -ECONNABORTED;
730 goto accept_err;
731 }
732
733 /* Get the new node's NODEID */
734 make_sockaddr(&peeraddr, 0, &len);
735 if (dlm_addr_to_nodeid(&peeraddr, &nodeid)) {
David Teigland617e82e2007-04-26 13:46:49 -0500736 log_print("connect from non cluster node");
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100737 sock_release(newsock);
738 mutex_unlock(&con->sock_mutex);
739 return -1;
740 }
741
742 log_print("got connection from %d", nodeid);
743
744 /* Check to see if we already have a connection to this node. This
745 * could happen if the two nodes initiate a connection at roughly
746 * the same time and the connections cross on the wire.
747 * In this case we store the incoming one in "othercon"
748 */
David Teigland748285c2009-05-15 10:50:57 -0500749 newcon = nodeid2con(nodeid, GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100750 if (!newcon) {
751 result = -ENOMEM;
752 goto accept_err;
753 }
754 mutex_lock_nested(&newcon->sock_mutex, 1);
755 if (newcon->sock) {
756 struct connection *othercon = newcon->othercon;
757
758 if (!othercon) {
David Teigland748285c2009-05-15 10:50:57 -0500759 othercon = kmem_cache_zalloc(con_cache, GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100760 if (!othercon) {
David Teigland617e82e2007-04-26 13:46:49 -0500761 log_print("failed to allocate incoming socket");
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100762 mutex_unlock(&newcon->sock_mutex);
763 result = -ENOMEM;
764 goto accept_err;
765 }
766 othercon->nodeid = nodeid;
767 othercon->rx_action = receive_from_sock;
768 mutex_init(&othercon->sock_mutex);
769 INIT_WORK(&othercon->swork, process_send_sockets);
770 INIT_WORK(&othercon->rwork, process_recv_sockets);
771 set_bit(CF_IS_OTHERCON, &othercon->flags);
Patrick Caulfield61d96be2007-08-20 15:13:38 +0100772 }
773 if (!othercon->sock) {
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100774 newcon->othercon = othercon;
Patrick Caulfield97d84832007-06-27 11:36:23 +0100775 othercon->sock = newsock;
776 newsock->sk->sk_user_data = othercon;
777 add_sock(newsock, othercon);
778 addcon = othercon;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100779 }
Patrick Caulfield97d84832007-06-27 11:36:23 +0100780 else {
781 printk("Extra connection from node %d attempted\n", nodeid);
782 result = -EAGAIN;
akpm@linux-foundation.orgf4fadb23c2007-06-27 14:43:37 -0700783 mutex_unlock(&newcon->sock_mutex);
Patrick Caulfield97d84832007-06-27 11:36:23 +0100784 goto accept_err;
785 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100786 }
787 else {
788 newsock->sk->sk_user_data = newcon;
789 newcon->rx_action = receive_from_sock;
790 add_sock(newsock, newcon);
791 addcon = newcon;
792 }
793
794 mutex_unlock(&newcon->sock_mutex);
795
796 /*
797 * Add it to the active queue in case we got data
798 * beween processing the accept adding the socket
799 * to the read_sockets list
800 */
801 if (!test_and_set_bit(CF_READ_PENDING, &addcon->flags))
802 queue_work(recv_workqueue, &addcon->rwork);
803 mutex_unlock(&con->sock_mutex);
804
805 return 0;
806
807accept_err:
808 mutex_unlock(&con->sock_mutex);
809 sock_release(newsock);
810
811 if (result != -EAGAIN)
David Teigland617e82e2007-04-26 13:46:49 -0500812 log_print("error accepting connection from node: %d", result);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100813 return result;
814}
815
816static void free_entry(struct writequeue_entry *e)
817{
818 __free_page(e->page);
819 kfree(e);
820}
821
822/* Initiate an SCTP association.
823 This is a special case of send_to_sock() in that we don't yet have a
824 peeled-off socket for this association, so we use the listening socket
825 and add the primary IP address of the remote node.
826 */
827static void sctp_init_assoc(struct connection *con)
828{
829 struct sockaddr_storage rem_addr;
830 char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
831 struct msghdr outmessage;
832 struct cmsghdr *cmsg;
833 struct sctp_sndrcvinfo *sinfo;
834 struct connection *base_con;
835 struct writequeue_entry *e;
836 int len, offset;
837 int ret;
838 int addrlen;
839 struct kvec iov[1];
840
841 if (test_and_set_bit(CF_INIT_PENDING, &con->flags))
842 return;
843
844 if (con->retries++ > MAX_CONNECT_RETRIES)
845 return;
846
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100847 if (nodeid_to_addr(con->nodeid, (struct sockaddr *)&rem_addr)) {
848 log_print("no address for nodeid %d", con->nodeid);
849 return;
850 }
851 base_con = nodeid2con(0, 0);
852 BUG_ON(base_con == NULL);
853
854 make_sockaddr(&rem_addr, dlm_config.ci_tcp_port, &addrlen);
855
856 outmessage.msg_name = &rem_addr;
857 outmessage.msg_namelen = addrlen;
858 outmessage.msg_control = outcmsg;
859 outmessage.msg_controllen = sizeof(outcmsg);
860 outmessage.msg_flags = MSG_EOR;
861
862 spin_lock(&con->writequeue_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100863
David Teigland04bedd72009-09-18 14:31:47 -0500864 if (list_empty(&con->writequeue)) {
865 spin_unlock(&con->writequeue_lock);
866 log_print("writequeue empty for nodeid %d", con->nodeid);
867 return;
868 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100869
David Teigland04bedd72009-09-18 14:31:47 -0500870 e = list_first_entry(&con->writequeue, struct writequeue_entry, list);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100871 len = e->len;
872 offset = e->offset;
873 spin_unlock(&con->writequeue_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100874
875 /* Send the first block off the write queue */
876 iov[0].iov_base = page_address(e->page)+offset;
877 iov[0].iov_len = len;
878
879 cmsg = CMSG_FIRSTHDR(&outmessage);
880 cmsg->cmsg_level = IPPROTO_SCTP;
881 cmsg->cmsg_type = SCTP_SNDRCV;
882 cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo));
883 sinfo = CMSG_DATA(cmsg);
884 memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo));
885 sinfo->sinfo_ppid = cpu_to_le32(dlm_our_nodeid());
886 outmessage.msg_controllen = cmsg->cmsg_len;
887
888 ret = kernel_sendmsg(base_con->sock, &outmessage, iov, 1, len);
889 if (ret < 0) {
David Teigland617e82e2007-04-26 13:46:49 -0500890 log_print("Send first packet to node %d failed: %d",
891 con->nodeid, ret);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100892
893 /* Try again later */
894 clear_bit(CF_CONNECT_PENDING, &con->flags);
895 clear_bit(CF_INIT_PENDING, &con->flags);
896 }
897 else {
898 spin_lock(&con->writequeue_lock);
899 e->offset += ret;
900 e->len -= ret;
901
902 if (e->len == 0 && e->users == 0) {
903 list_del(&e->list);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100904 free_entry(e);
905 }
906 spin_unlock(&con->writequeue_lock);
907 }
908}
909
910/* Connect a new socket to its peer */
911static void tcp_connect_to_sock(struct connection *con)
912{
913 int result = -EHOSTUNREACH;
Lon Hohberger6bd8fed2007-10-25 18:51:54 -0400914 struct sockaddr_storage saddr, src_addr;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100915 int addr_len;
Casey Dahlina89d63a2009-07-14 12:17:51 -0500916 struct socket *sock = NULL;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100917
918 if (con->nodeid == 0) {
919 log_print("attempt to connect sock 0 foiled");
920 return;
921 }
922
923 mutex_lock(&con->sock_mutex);
924 if (con->retries++ > MAX_CONNECT_RETRIES)
925 goto out;
926
927 /* Some odd races can cause double-connects, ignore them */
928 if (con->sock) {
929 result = 0;
930 goto out;
931 }
932
933 /* Create a socket to communicate with */
934 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_STREAM,
935 IPPROTO_TCP, &sock);
936 if (result < 0)
937 goto out_err;
938
939 memset(&saddr, 0, sizeof(saddr));
Casey Dahlinb5711b82009-07-28 12:29:05 -0500940 if (dlm_nodeid_to_addr(con->nodeid, &saddr))
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100941 goto out_err;
942
943 sock->sk->sk_user_data = con;
944 con->rx_action = receive_from_sock;
945 con->connect_action = tcp_connect_to_sock;
946 add_sock(sock, con);
947
Lon Hohberger6bd8fed2007-10-25 18:51:54 -0400948 /* Bind to our cluster-known address connecting to avoid
949 routing problems */
950 memcpy(&src_addr, dlm_local_addr[0], sizeof(src_addr));
951 make_sockaddr(&src_addr, 0, &addr_len);
952 result = sock->ops->bind(sock, (struct sockaddr *) &src_addr,
953 addr_len);
954 if (result < 0) {
955 log_print("could not bind for connect: %d", result);
956 /* This *may* not indicate a critical error */
957 }
958
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100959 make_sockaddr(&saddr, dlm_config.ci_tcp_port, &addr_len);
960
961 log_print("connecting to %d", con->nodeid);
962 result =
963 sock->ops->connect(sock, (struct sockaddr *)&saddr, addr_len,
964 O_NONBLOCK);
965 if (result == -EINPROGRESS)
966 result = 0;
967 if (result == 0)
968 goto out;
969
970out_err:
971 if (con->sock) {
972 sock_release(con->sock);
973 con->sock = NULL;
Casey Dahlina89d63a2009-07-14 12:17:51 -0500974 } else if (sock) {
975 sock_release(sock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100976 }
977 /*
978 * Some errors are fatal and this list might need adjusting. For other
979 * errors we try again until the max number of retries is reached.
980 */
981 if (result != -EHOSTUNREACH && result != -ENETUNREACH &&
Marcin Slusarz0035a4b2008-05-11 22:01:29 +0200982 result != -ENETDOWN && result != -EINVAL
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +0100983 && result != -EPROTONOSUPPORT) {
984 lowcomms_connect_sock(con);
985 result = 0;
986 }
987out:
988 mutex_unlock(&con->sock_mutex);
989 return;
990}
991
992static struct socket *tcp_create_listen_sock(struct connection *con,
993 struct sockaddr_storage *saddr)
994{
995 struct socket *sock = NULL;
996 int result = 0;
997 int one = 1;
998 int addr_len;
999
1000 if (dlm_local_addr[0]->ss_family == AF_INET)
1001 addr_len = sizeof(struct sockaddr_in);
1002 else
1003 addr_len = sizeof(struct sockaddr_in6);
1004
1005 /* Create a socket to communicate with */
David Teigland617e82e2007-04-26 13:46:49 -05001006 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_STREAM,
1007 IPPROTO_TCP, &sock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001008 if (result < 0) {
David Teigland617e82e2007-04-26 13:46:49 -05001009 log_print("Can't create listening comms socket");
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001010 goto create_out;
1011 }
1012
1013 result = kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
1014 (char *)&one, sizeof(one));
1015
1016 if (result < 0) {
David Teigland617e82e2007-04-26 13:46:49 -05001017 log_print("Failed to set SO_REUSEADDR on socket: %d", result);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001018 }
1019 sock->sk->sk_user_data = con;
1020 con->rx_action = tcp_accept_from_sock;
1021 con->connect_action = tcp_connect_to_sock;
1022 con->sock = sock;
1023
1024 /* Bind to our port */
1025 make_sockaddr(saddr, dlm_config.ci_tcp_port, &addr_len);
1026 result = sock->ops->bind(sock, (struct sockaddr *) saddr, addr_len);
1027 if (result < 0) {
David Teigland617e82e2007-04-26 13:46:49 -05001028 log_print("Can't bind to port %d", dlm_config.ci_tcp_port);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001029 sock_release(sock);
1030 sock = NULL;
1031 con->sock = NULL;
1032 goto create_out;
1033 }
1034 result = kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
1035 (char *)&one, sizeof(one));
1036 if (result < 0) {
David Teigland617e82e2007-04-26 13:46:49 -05001037 log_print("Set keepalive failed: %d", result);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001038 }
1039
1040 result = sock->ops->listen(sock, 5);
1041 if (result < 0) {
David Teigland617e82e2007-04-26 13:46:49 -05001042 log_print("Can't listen on port %d", dlm_config.ci_tcp_port);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001043 sock_release(sock);
1044 sock = NULL;
1045 goto create_out;
1046 }
1047
1048create_out:
1049 return sock;
1050}
1051
1052/* Get local addresses */
1053static void init_local(void)
1054{
1055 struct sockaddr_storage sas, *addr;
1056 int i;
1057
Patrick Caulfield30d3a232007-04-23 16:26:21 +01001058 dlm_local_count = 0;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001059 for (i = 0; i < DLM_MAX_ADDR_COUNT - 1; i++) {
1060 if (dlm_our_addr(&sas, i))
1061 break;
1062
David Teigland573c24c2009-11-30 16:34:43 -06001063 addr = kmalloc(sizeof(*addr), GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001064 if (!addr)
1065 break;
1066 memcpy(addr, &sas, sizeof(*addr));
1067 dlm_local_addr[dlm_local_count++] = addr;
1068 }
1069}
1070
David Teigland617e82e2007-04-26 13:46:49 -05001071/* Bind to an IP address. SCTP allows multiple address so it can do
1072 multi-homing */
1073static int add_sctp_bind_addr(struct connection *sctp_con,
1074 struct sockaddr_storage *addr,
1075 int addr_len, int num)
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001076{
1077 int result = 0;
1078
1079 if (num == 1)
1080 result = kernel_bind(sctp_con->sock,
1081 (struct sockaddr *) addr,
1082 addr_len);
1083 else
1084 result = kernel_setsockopt(sctp_con->sock, SOL_SCTP,
1085 SCTP_SOCKOPT_BINDX_ADD,
1086 (char *)addr, addr_len);
1087
1088 if (result < 0)
1089 log_print("Can't bind to port %d addr number %d",
1090 dlm_config.ci_tcp_port, num);
1091
1092 return result;
1093}
1094
1095/* Initialise SCTP socket and bind to all interfaces */
1096static int sctp_listen_for_all(void)
1097{
1098 struct socket *sock = NULL;
1099 struct sockaddr_storage localaddr;
1100 struct sctp_event_subscribe subscribe;
1101 int result = -EINVAL, num = 1, i, addr_len;
David Teigland573c24c2009-11-30 16:34:43 -06001102 struct connection *con = nodeid2con(0, GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001103 int bufsize = NEEDED_RMEM;
1104
1105 if (!con)
1106 return -ENOMEM;
1107
1108 log_print("Using SCTP for communications");
1109
1110 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_SEQPACKET,
1111 IPPROTO_SCTP, &sock);
1112 if (result < 0) {
1113 log_print("Can't create comms socket, check SCTP is loaded");
1114 goto out;
1115 }
1116
1117 /* Listen for events */
1118 memset(&subscribe, 0, sizeof(subscribe));
1119 subscribe.sctp_data_io_event = 1;
1120 subscribe.sctp_association_event = 1;
1121 subscribe.sctp_send_failure_event = 1;
1122 subscribe.sctp_shutdown_event = 1;
1123 subscribe.sctp_partial_delivery_event = 1;
1124
David S. Millerdf61c952007-11-06 23:48:57 -08001125 result = kernel_setsockopt(sock, SOL_SOCKET, SO_RCVBUFFORCE,
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001126 (char *)&bufsize, sizeof(bufsize));
1127 if (result)
David Teigland617e82e2007-04-26 13:46:49 -05001128 log_print("Error increasing buffer space on socket %d", result);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001129
1130 result = kernel_setsockopt(sock, SOL_SCTP, SCTP_EVENTS,
David Teigland617e82e2007-04-26 13:46:49 -05001131 (char *)&subscribe, sizeof(subscribe));
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001132 if (result < 0) {
1133 log_print("Failed to set SCTP_EVENTS on socket: result=%d",
1134 result);
1135 goto create_delsock;
1136 }
1137
1138 /* Init con struct */
1139 sock->sk->sk_user_data = con;
1140 con->sock = sock;
1141 con->sock->sk->sk_data_ready = lowcomms_data_ready;
1142 con->rx_action = receive_from_sock;
1143 con->connect_action = sctp_init_assoc;
1144
1145 /* Bind to all interfaces. */
1146 for (i = 0; i < dlm_local_count; i++) {
1147 memcpy(&localaddr, dlm_local_addr[i], sizeof(localaddr));
1148 make_sockaddr(&localaddr, dlm_config.ci_tcp_port, &addr_len);
1149
1150 result = add_sctp_bind_addr(con, &localaddr, addr_len, num);
1151 if (result)
1152 goto create_delsock;
1153 ++num;
1154 }
1155
1156 result = sock->ops->listen(sock, 5);
1157 if (result < 0) {
1158 log_print("Can't set socket listening");
1159 goto create_delsock;
1160 }
1161
1162 return 0;
1163
1164create_delsock:
1165 sock_release(sock);
1166 con->sock = NULL;
1167out:
1168 return result;
1169}
1170
1171static int tcp_listen_for_all(void)
1172{
1173 struct socket *sock = NULL;
David Teigland573c24c2009-11-30 16:34:43 -06001174 struct connection *con = nodeid2con(0, GFP_NOFS);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001175 int result = -EINVAL;
1176
1177 if (!con)
1178 return -ENOMEM;
1179
1180 /* We don't support multi-homed hosts */
1181 if (dlm_local_addr[1] != NULL) {
David Teigland617e82e2007-04-26 13:46:49 -05001182 log_print("TCP protocol can't handle multi-homed hosts, "
1183 "try SCTP");
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001184 return -EINVAL;
1185 }
1186
1187 log_print("Using TCP for communications");
1188
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001189 sock = tcp_create_listen_sock(con, dlm_local_addr[0]);
1190 if (sock) {
1191 add_sock(sock, con);
1192 result = 0;
1193 }
1194 else {
1195 result = -EADDRINUSE;
1196 }
1197
1198 return result;
1199}
1200
1201
1202
1203static struct writequeue_entry *new_writequeue_entry(struct connection *con,
1204 gfp_t allocation)
1205{
1206 struct writequeue_entry *entry;
1207
1208 entry = kmalloc(sizeof(struct writequeue_entry), allocation);
1209 if (!entry)
1210 return NULL;
1211
1212 entry->page = alloc_page(allocation);
1213 if (!entry->page) {
1214 kfree(entry);
1215 return NULL;
1216 }
1217
1218 entry->offset = 0;
1219 entry->len = 0;
1220 entry->end = 0;
1221 entry->users = 0;
1222 entry->con = con;
1223
1224 return entry;
1225}
1226
David Teigland617e82e2007-04-26 13:46:49 -05001227void *dlm_lowcomms_get_buffer(int nodeid, int len, gfp_t allocation, char **ppc)
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001228{
1229 struct connection *con;
1230 struct writequeue_entry *e;
1231 int offset = 0;
1232 int users = 0;
1233
1234 con = nodeid2con(nodeid, allocation);
1235 if (!con)
1236 return NULL;
1237
1238 spin_lock(&con->writequeue_lock);
1239 e = list_entry(con->writequeue.prev, struct writequeue_entry, list);
1240 if ((&e->list == &con->writequeue) ||
1241 (PAGE_CACHE_SIZE - e->end < len)) {
1242 e = NULL;
1243 } else {
1244 offset = e->end;
1245 e->end += len;
1246 users = e->users++;
1247 }
1248 spin_unlock(&con->writequeue_lock);
1249
1250 if (e) {
1251 got_one:
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001252 *ppc = page_address(e->page) + offset;
1253 return e;
1254 }
1255
1256 e = new_writequeue_entry(con, allocation);
1257 if (e) {
1258 spin_lock(&con->writequeue_lock);
1259 offset = e->end;
1260 e->end += len;
1261 users = e->users++;
1262 list_add_tail(&e->list, &con->writequeue);
1263 spin_unlock(&con->writequeue_lock);
1264 goto got_one;
1265 }
1266 return NULL;
1267}
1268
1269void dlm_lowcomms_commit_buffer(void *mh)
1270{
1271 struct writequeue_entry *e = (struct writequeue_entry *)mh;
1272 struct connection *con = e->con;
1273 int users;
1274
1275 spin_lock(&con->writequeue_lock);
1276 users = --e->users;
1277 if (users)
1278 goto out;
1279 e->len = e->end - e->offset;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001280 spin_unlock(&con->writequeue_lock);
1281
1282 if (!test_and_set_bit(CF_WRITE_PENDING, &con->flags)) {
1283 queue_work(send_workqueue, &con->swork);
1284 }
1285 return;
1286
1287out:
1288 spin_unlock(&con->writequeue_lock);
1289 return;
1290}
1291
1292/* Send a message */
1293static void send_to_sock(struct connection *con)
1294{
1295 int ret = 0;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001296 const int msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL;
1297 struct writequeue_entry *e;
1298 int len, offset;
1299
1300 mutex_lock(&con->sock_mutex);
1301 if (con->sock == NULL)
1302 goto out_connect;
1303
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001304 spin_lock(&con->writequeue_lock);
1305 for (;;) {
1306 e = list_entry(con->writequeue.next, struct writequeue_entry,
1307 list);
1308 if ((struct list_head *) e == &con->writequeue)
1309 break;
1310
1311 len = e->len;
1312 offset = e->offset;
1313 BUG_ON(len == 0 && e->users == 0);
1314 spin_unlock(&con->writequeue_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001315
1316 ret = 0;
1317 if (len) {
Paolo Bonzini1329e3f2009-08-24 13:18:04 -05001318 ret = kernel_sendpage(con->sock, e->page, offset, len,
1319 msg_flags);
Patrick Caulfieldd66f8272007-09-14 08:49:21 +01001320 if (ret == -EAGAIN || ret == 0) {
1321 cond_resched();
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001322 goto out;
Patrick Caulfieldd66f8272007-09-14 08:49:21 +01001323 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001324 if (ret <= 0)
1325 goto send_error;
Patrick Caulfieldd66f8272007-09-14 08:49:21 +01001326 }
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001327 /* Don't starve people filling buffers */
1328 cond_resched();
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001329
1330 spin_lock(&con->writequeue_lock);
1331 e->offset += ret;
1332 e->len -= ret;
1333
1334 if (e->len == 0 && e->users == 0) {
1335 list_del(&e->list);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001336 free_entry(e);
1337 continue;
1338 }
1339 }
1340 spin_unlock(&con->writequeue_lock);
1341out:
1342 mutex_unlock(&con->sock_mutex);
1343 return;
1344
1345send_error:
1346 mutex_unlock(&con->sock_mutex);
1347 close_connection(con, false);
1348 lowcomms_connect_sock(con);
1349 return;
1350
1351out_connect:
1352 mutex_unlock(&con->sock_mutex);
1353 if (!test_bit(CF_INIT_PENDING, &con->flags))
1354 lowcomms_connect_sock(con);
1355 return;
1356}
1357
1358static void clean_one_writequeue(struct connection *con)
1359{
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001360 struct writequeue_entry *e, *safe;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001361
1362 spin_lock(&con->writequeue_lock);
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001363 list_for_each_entry_safe(e, safe, &con->writequeue, list) {
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001364 list_del(&e->list);
1365 free_entry(e);
1366 }
1367 spin_unlock(&con->writequeue_lock);
1368}
1369
1370/* Called from recovery when it knows that a node has
1371 left the cluster */
1372int dlm_lowcomms_close(int nodeid)
1373{
1374 struct connection *con;
1375
1376 log_print("closing connection to node %d", nodeid);
1377 con = nodeid2con(nodeid, 0);
1378 if (con) {
Lars Marowsky-Bree063c4c92009-08-11 16:18:23 -05001379 clear_bit(CF_CONNECT_PENDING, &con->flags);
1380 clear_bit(CF_WRITE_PENDING, &con->flags);
1381 set_bit(CF_CLOSE, &con->flags);
1382 if (cancel_work_sync(&con->swork))
1383 log_print("canceled swork for node %d", nodeid);
1384 if (cancel_work_sync(&con->rwork))
1385 log_print("canceled rwork for node %d", nodeid);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001386 clean_one_writequeue(con);
1387 close_connection(con, true);
1388 }
1389 return 0;
1390}
1391
1392/* Receive workqueue function */
1393static void process_recv_sockets(struct work_struct *work)
1394{
1395 struct connection *con = container_of(work, struct connection, rwork);
1396 int err;
1397
1398 clear_bit(CF_READ_PENDING, &con->flags);
1399 do {
1400 err = con->rx_action(con);
1401 } while (!err);
1402}
1403
1404/* Send workqueue function */
1405static void process_send_sockets(struct work_struct *work)
1406{
1407 struct connection *con = container_of(work, struct connection, swork);
1408
1409 if (test_and_clear_bit(CF_CONNECT_PENDING, &con->flags)) {
1410 con->connect_action(con);
Lars Marowsky-Bree063c4c92009-08-11 16:18:23 -05001411 set_bit(CF_WRITE_PENDING, &con->flags);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001412 }
Lars Marowsky-Bree063c4c92009-08-11 16:18:23 -05001413 if (test_and_clear_bit(CF_WRITE_PENDING, &con->flags))
1414 send_to_sock(con);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001415}
1416
1417
1418/* Discard all entries on the write queues */
1419static void clean_writequeues(void)
1420{
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001421 foreach_conn(clean_one_writequeue);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001422}
1423
1424static void work_stop(void)
1425{
1426 destroy_workqueue(recv_workqueue);
1427 destroy_workqueue(send_workqueue);
1428}
1429
1430static int work_start(void)
1431{
1432 int error;
1433 recv_workqueue = create_workqueue("dlm_recv");
1434 error = IS_ERR(recv_workqueue);
1435 if (error) {
1436 log_print("can't start dlm_recv %d", error);
1437 return error;
1438 }
1439
1440 send_workqueue = create_singlethread_workqueue("dlm_send");
1441 error = IS_ERR(send_workqueue);
1442 if (error) {
1443 log_print("can't start dlm_send %d", error);
1444 destroy_workqueue(recv_workqueue);
1445 return error;
1446 }
1447
1448 return 0;
1449}
1450
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001451static void stop_conn(struct connection *con)
1452{
1453 con->flags |= 0x0F;
Christine Caulfield391fbdc2009-05-07 10:54:16 -05001454 if (con->sock && con->sock->sk)
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001455 con->sock->sk->sk_user_data = NULL;
1456}
1457
1458static void free_conn(struct connection *con)
1459{
1460 close_connection(con, true);
1461 if (con->othercon)
1462 kmem_cache_free(con_cache, con->othercon);
1463 hlist_del(&con->list);
1464 kmem_cache_free(con_cache, con);
1465}
1466
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001467void dlm_lowcomms_stop(void)
1468{
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001469 /* Set all the flags to prevent any
1470 socket activity.
1471 */
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -05001472 mutex_lock(&connections_lock);
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001473 foreach_conn(stop_conn);
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -05001474 mutex_unlock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001475
1476 work_stop();
1477
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -05001478 mutex_lock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001479 clean_writequeues();
1480
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001481 foreach_conn(free_conn);
1482
Matthias Kaehlcke7a936ce2008-05-12 10:04:51 -05001483 mutex_unlock(&connections_lock);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001484 kmem_cache_destroy(con_cache);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001485}
1486
1487int dlm_lowcomms_start(void)
1488{
1489 int error = -EINVAL;
1490 struct connection *con;
Christine Caulfield5e9ccc32009-01-28 12:57:40 -06001491 int i;
1492
1493 for (i = 0; i < CONN_HASH_SIZE; i++)
1494 INIT_HLIST_HEAD(&connection_hash[i]);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001495
1496 init_local();
1497 if (!dlm_local_count) {
David Teigland617e82e2007-04-26 13:46:49 -05001498 error = -ENOTCONN;
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001499 log_print("no local IP address has been set");
1500 goto out;
1501 }
1502
1503 error = -ENOMEM;
1504 con_cache = kmem_cache_create("dlm_conn", sizeof(struct connection),
1505 __alignof__(struct connection), 0,
Paul Mundt20c2df82007-07-20 10:11:58 +09001506 NULL);
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001507 if (!con_cache)
1508 goto out;
1509
Patrick Caulfield6ed7257b2007-04-17 15:39:57 +01001510 /* Start listening */
1511 if (dlm_config.ci_protocol == 0)
1512 error = tcp_listen_for_all();
1513 else
1514 error = sctp_listen_for_all();
1515 if (error)
1516 goto fail_unlisten;
1517
1518 error = work_start();
1519 if (error)
1520 goto fail_unlisten;
1521
1522 return 0;
1523
1524fail_unlisten:
1525 con = nodeid2con(0,0);
1526 if (con) {
1527 close_connection(con, false);
1528 kmem_cache_free(con_cache, con);
1529 }
1530 kmem_cache_destroy(con_cache);
1531
1532out:
1533 return error;
1534}