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2522fe45 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
e7fd4179 DT |
2 | /****************************************************************************** |
3 | ******************************************************************************* | |
4 | ** | |
5 | ** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
489d8e55 | 6 | ** Copyright (C) 2004-2021 Red Hat, Inc. All rights reserved. |
e7fd4179 | 7 | ** |
e7fd4179 DT |
8 | ** |
9 | ******************************************************************************* | |
10 | ******************************************************************************/ | |
11 | ||
12 | /* | |
13 | * midcomms.c | |
14 | * | |
489d8e55 AA |
15 | * This is the appallingly named "mid-level" comms layer. It takes care about |
16 | * deliver an on application layer "reliable" communication above the used | |
17 | * lowcomms transport layer. | |
e7fd4179 | 18 | * |
489d8e55 | 19 | * How it works: |
e7fd4179 | 20 | * |
489d8e55 AA |
21 | * Each nodes keeps track of all send DLM messages in send_queue with a sequence |
22 | * number. The receive will send an DLM_ACK message back for every DLM message | |
23 | * received at the other side. If a reconnect happens in lowcomms we will send | |
24 | * all unacknowledged dlm messages again. The receiving side might drop any already | |
25 | * received message by comparing sequence numbers. | |
26 | * | |
27 | * How version detection works: | |
28 | * | |
29 | * Due the fact that dlm has pre-configured node addresses on every side | |
30 | * it is in it's nature that every side connects at starts to transmit | |
31 | * dlm messages which ends in a race. However DLM_RCOM_NAMES, DLM_RCOM_STATUS | |
32 | * and their replies are the first messages which are exchanges. Due backwards | |
33 | * compatibility these messages are not covered by the midcomms re-transmission | |
34 | * layer. These messages have their own re-transmission handling in the dlm | |
35 | * application layer. The version field of every node will be set on these RCOM | |
36 | * messages as soon as they arrived and the node isn't yet part of the nodes | |
37 | * hash. There exists also logic to detect version mismatched if something weird | |
38 | * going on or the first messages isn't an expected one. | |
39 | * | |
40 | * Termination: | |
41 | * | |
42 | * The midcomms layer does a 4 way handshake for termination on DLM protocol | |
43 | * like TCP supports it with half-closed socket support. SCTP doesn't support | |
44 | * half-closed socket, so we do it on DLM layer. Also socket shutdown() can be | |
45 | * interrupted by .e.g. tcp reset itself. Additional there exists the othercon | |
46 | * paradigm in lowcomms which cannot be easily without breaking backwards | |
47 | * compatibility. A node cannot send anything to another node when a DLM_FIN | |
48 | * message was send. There exists additional logic to print a warning if | |
49 | * DLM wants to do it. There exists a state handling like RFC 793 but reduced | |
50 | * to termination only. The event "member removal event" describes the cluster | |
51 | * manager removed the node from internal lists, at this point DLM does not | |
52 | * send any message to the other node. There exists two cases: | |
53 | * | |
54 | * 1. The cluster member was removed and we received a FIN | |
55 | * OR | |
56 | * 2. We received a FIN but the member was not removed yet | |
57 | * | |
58 | * One of these cases will do the CLOSE_WAIT to LAST_ACK change. | |
59 | * | |
60 | * | |
61 | * +---------+ | |
62 | * | CLOSED | | |
63 | * +---------+ | |
64 | * | add member/receive RCOM version | |
65 | * | detection msg | |
66 | * V | |
67 | * +---------+ | |
68 | * | ESTAB | | |
69 | * +---------+ | |
70 | * CLOSE | | rcv FIN | |
71 | * ------- | | ------- | |
72 | * +---------+ snd FIN / \ snd ACK +---------+ | |
73 | * | FIN |<----------------- ------------------>| CLOSE | | |
74 | * | WAIT-1 |------------------ | WAIT | | |
75 | * +---------+ rcv FIN \ +---------+ | |
76 | * | rcv ACK of FIN ------- | CLOSE | member | |
77 | * | -------------- snd ACK | ------- | removal | |
78 | * V x V snd FIN V event | |
79 | * +---------+ +---------+ +---------+ | |
80 | * |FINWAIT-2| | CLOSING | | LAST-ACK| | |
81 | * +---------+ +---------+ +---------+ | |
82 | * | rcv ACK of FIN | rcv ACK of FIN | | |
83 | * | rcv FIN -------------- | -------------- | | |
84 | * | ------- x V x V | |
85 | * \ snd ACK +---------+ +---------+ | |
86 | * ------------------------>| CLOSED | | CLOSED | | |
87 | * +---------+ +---------+ | |
88 | * | |
89 | * NOTE: any state can interrupted by midcomms_close() and state will be | |
90 | * switched to CLOSED in case of fencing. There exists also some timeout | |
91 | * handling when we receive the version detection RCOM messages which is | |
92 | * made by observation. | |
93 | * | |
94 | * Future improvements: | |
95 | * | |
96 | * There exists some known issues/improvements of the dlm handling. Some | |
97 | * of them should be done in a next major dlm version bump which makes | |
98 | * it incompatible with previous versions. | |
99 | * | |
100 | * Unaligned memory access: | |
101 | * | |
102 | * There exists cases when the dlm message buffer length is not aligned | |
103 | * to 8 byte. However seems nobody detected any problem with it. This | |
104 | * can be fixed in the next major version bump of dlm. | |
105 | * | |
106 | * Version detection: | |
107 | * | |
108 | * The version detection and how it's done is related to backwards | |
109 | * compatibility. There exists better ways to make a better handling. | |
110 | * However this should be changed in the next major version bump of dlm. | |
111 | * | |
489d8e55 AA |
112 | * Tail Size checking: |
113 | * | |
114 | * There exists a message tail payload in e.g. DLM_MSG however we don't | |
115 | * check it against the message length yet regarding to the receive buffer | |
116 | * length. That need to be validated. | |
117 | * | |
118 | * Fencing bad nodes: | |
119 | * | |
120 | * At timeout places or weird sequence number behaviours we should send | |
121 | * a fencing request to the cluster manager. | |
e7fd4179 DT |
122 | */ |
123 | ||
489d8e55 AA |
124 | /* Debug switch to enable a 5 seconds sleep waiting of a termination. |
125 | * This can be useful to test fencing while termination is running. | |
126 | * This requires a setup with only gfs2 as dlm user, so that the | |
127 | * last umount will terminate the connection. | |
128 | * | |
129 | * However it became useful to test, while the 5 seconds block in umount | |
130 | * just press the reset button. In a lot of dropping the termination | |
131 | * process can could take several seconds. | |
132 | */ | |
133 | #define DLM_DEBUG_FENCE_TERMINATION 0 | |
134 | ||
e01c4b7b | 135 | #include <trace/events/dlm.h> |
489d8e55 AA |
136 | #include <net/tcp.h> |
137 | ||
e7fd4179 DT |
138 | #include "dlm_internal.h" |
139 | #include "lowcomms.h" | |
140 | #include "config.h" | |
6c547f26 | 141 | #include "memory.h" |
e7fd4179 | 142 | #include "lock.h" |
489d8e55 | 143 | #include "util.h" |
e7fd4179 DT |
144 | #include "midcomms.h" |
145 | ||
489d8e55 AA |
146 | /* init value for sequence numbers for testing purpose only e.g. overflows */ |
147 | #define DLM_SEQ_INIT 0 | |
11605353 AA |
148 | /* 5 seconds wait to sync ending of dlm */ |
149 | #define DLM_SHUTDOWN_TIMEOUT msecs_to_jiffies(5000) | |
489d8e55 | 150 | #define DLM_VERSION_NOT_SET 0 |
1696c75f AA |
151 | #define DLM_SEND_ACK_BACK_MSG_THRESHOLD 32 |
152 | #define DLM_RECV_ACK_BACK_MSG_THRESHOLD (DLM_SEND_ACK_BACK_MSG_THRESHOLD * 8) | |
489d8e55 AA |
153 | |
154 | struct midcomms_node { | |
155 | int nodeid; | |
156 | uint32_t version; | |
d00725ca AA |
157 | atomic_t seq_send; |
158 | atomic_t seq_next; | |
489d8e55 AA |
159 | /* These queues are unbound because we cannot drop any message in dlm. |
160 | * We could send a fence signal for a specific node to the cluster | |
161 | * manager if queues hits some maximum value, however this handling | |
162 | * not supported yet. | |
163 | */ | |
164 | struct list_head send_queue; | |
165 | spinlock_t send_queue_lock; | |
166 | atomic_t send_queue_cnt; | |
167 | #define DLM_NODE_FLAG_CLOSE 1 | |
168 | #define DLM_NODE_FLAG_STOP_TX 2 | |
169 | #define DLM_NODE_FLAG_STOP_RX 3 | |
1696c75f | 170 | atomic_t ulp_delivered; |
489d8e55 AA |
171 | unsigned long flags; |
172 | wait_queue_head_t shutdown_wait; | |
173 | ||
174 | /* dlm tcp termination state */ | |
175 | #define DLM_CLOSED 1 | |
176 | #define DLM_ESTABLISHED 2 | |
177 | #define DLM_FIN_WAIT1 3 | |
178 | #define DLM_FIN_WAIT2 4 | |
179 | #define DLM_CLOSE_WAIT 5 | |
180 | #define DLM_LAST_ACK 6 | |
181 | #define DLM_CLOSING 7 | |
182 | int state; | |
183 | spinlock_t state_lock; | |
184 | ||
185 | /* counts how many lockspaces are using this node | |
186 | * this refcount is necessary to determine if the | |
187 | * node wants to disconnect. | |
188 | */ | |
189 | int users; | |
190 | ||
5b2f981f AA |
191 | /* not protected by srcu, node_hash lifetime */ |
192 | void *debugfs; | |
193 | ||
489d8e55 AA |
194 | struct hlist_node hlist; |
195 | struct rcu_head rcu; | |
196 | }; | |
197 | ||
198 | struct dlm_mhandle { | |
5b787667 | 199 | const union dlm_packet *inner_p; |
489d8e55 AA |
200 | struct midcomms_node *node; |
201 | struct dlm_opts *opts; | |
202 | struct dlm_msg *msg; | |
203 | bool committed; | |
204 | uint32_t seq; | |
205 | ||
206 | void (*ack_rcv)(struct midcomms_node *node); | |
207 | ||
208 | /* get_mhandle/commit srcu idx exchange */ | |
209 | int idx; | |
210 | ||
211 | struct list_head list; | |
212 | struct rcu_head rcu; | |
213 | }; | |
214 | ||
215 | static struct hlist_head node_hash[CONN_HASH_SIZE]; | |
216 | static DEFINE_SPINLOCK(nodes_lock); | |
217 | DEFINE_STATIC_SRCU(nodes_srcu); | |
218 | ||
219 | /* This mutex prevents that midcomms_close() is running while | |
220 | * stop() or remove(). As I experienced invalid memory access | |
221 | * behaviours when DLM_DEBUG_FENCE_TERMINATION is enabled and | |
222 | * resetting machines. I will end in some double deletion in nodes | |
223 | * datastructure. | |
224 | */ | |
225 | static DEFINE_MUTEX(close_lock); | |
226 | ||
6c547f26 AA |
227 | struct kmem_cache *dlm_midcomms_cache_create(void) |
228 | { | |
229 | return kmem_cache_create("dlm_mhandle", sizeof(struct dlm_mhandle), | |
230 | 0, 0, NULL); | |
231 | } | |
232 | ||
489d8e55 | 233 | static inline const char *dlm_state_str(int state) |
a070a91c | 234 | { |
489d8e55 AA |
235 | switch (state) { |
236 | case DLM_CLOSED: | |
237 | return "CLOSED"; | |
238 | case DLM_ESTABLISHED: | |
239 | return "ESTABLISHED"; | |
240 | case DLM_FIN_WAIT1: | |
241 | return "FIN_WAIT1"; | |
242 | case DLM_FIN_WAIT2: | |
243 | return "FIN_WAIT2"; | |
244 | case DLM_CLOSE_WAIT: | |
245 | return "CLOSE_WAIT"; | |
246 | case DLM_LAST_ACK: | |
247 | return "LAST_ACK"; | |
248 | case DLM_CLOSING: | |
249 | return "CLOSING"; | |
250 | default: | |
251 | return "UNKNOWN"; | |
252 | } | |
a070a91c AA |
253 | } |
254 | ||
5b2f981f AA |
255 | const char *dlm_midcomms_state(struct midcomms_node *node) |
256 | { | |
257 | return dlm_state_str(node->state); | |
258 | } | |
259 | ||
260 | unsigned long dlm_midcomms_flags(struct midcomms_node *node) | |
261 | { | |
262 | return node->flags; | |
263 | } | |
264 | ||
265 | int dlm_midcomms_send_queue_cnt(struct midcomms_node *node) | |
266 | { | |
267 | return atomic_read(&node->send_queue_cnt); | |
268 | } | |
269 | ||
270 | uint32_t dlm_midcomms_version(struct midcomms_node *node) | |
271 | { | |
272 | return node->version; | |
273 | } | |
274 | ||
489d8e55 | 275 | static struct midcomms_node *__find_node(int nodeid, int r) |
a070a91c | 276 | { |
489d8e55 AA |
277 | struct midcomms_node *node; |
278 | ||
279 | hlist_for_each_entry_rcu(node, &node_hash[r], hlist) { | |
280 | if (node->nodeid == nodeid) | |
281 | return node; | |
282 | } | |
283 | ||
284 | return NULL; | |
a070a91c AA |
285 | } |
286 | ||
489d8e55 AA |
287 | static void dlm_mhandle_release(struct rcu_head *rcu) |
288 | { | |
289 | struct dlm_mhandle *mh = container_of(rcu, struct dlm_mhandle, rcu); | |
a070a91c | 290 | |
489d8e55 | 291 | dlm_lowcomms_put_msg(mh->msg); |
6c547f26 | 292 | dlm_free_mhandle(mh); |
489d8e55 | 293 | } |
a070a91c | 294 | |
f5fe8d51 AA |
295 | static void dlm_mhandle_delete(struct midcomms_node *node, |
296 | struct dlm_mhandle *mh) | |
297 | { | |
298 | list_del_rcu(&mh->list); | |
299 | atomic_dec(&node->send_queue_cnt); | |
300 | call_rcu(&mh->rcu, dlm_mhandle_release); | |
301 | } | |
302 | ||
489d8e55 | 303 | static void dlm_send_queue_flush(struct midcomms_node *node) |
a070a91c | 304 | { |
489d8e55 AA |
305 | struct dlm_mhandle *mh; |
306 | ||
307 | pr_debug("flush midcomms send queue of node %d\n", node->nodeid); | |
308 | ||
309 | rcu_read_lock(); | |
dbb751ff | 310 | spin_lock_bh(&node->send_queue_lock); |
489d8e55 | 311 | list_for_each_entry_rcu(mh, &node->send_queue, list) { |
f5fe8d51 | 312 | dlm_mhandle_delete(node, mh); |
489d8e55 | 313 | } |
dbb751ff | 314 | spin_unlock_bh(&node->send_queue_lock); |
489d8e55 | 315 | rcu_read_unlock(); |
a070a91c AA |
316 | } |
317 | ||
489d8e55 | 318 | static void midcomms_node_reset(struct midcomms_node *node) |
a070a91c | 319 | { |
489d8e55 AA |
320 | pr_debug("reset node %d\n", node->nodeid); |
321 | ||
d00725ca AA |
322 | atomic_set(&node->seq_next, DLM_SEQ_INIT); |
323 | atomic_set(&node->seq_send, DLM_SEQ_INIT); | |
1696c75f | 324 | atomic_set(&node->ulp_delivered, 0); |
489d8e55 AA |
325 | node->version = DLM_VERSION_NOT_SET; |
326 | node->flags = 0; | |
327 | ||
328 | dlm_send_queue_flush(node); | |
329 | node->state = DLM_CLOSED; | |
330 | wake_up(&node->shutdown_wait); | |
a070a91c AA |
331 | } |
332 | ||
63e711b0 | 333 | static struct midcomms_node *nodeid2node(int nodeid) |
489d8e55 | 334 | { |
63e711b0 AA |
335 | return __find_node(nodeid, nodeid_hash(nodeid)); |
336 | } | |
337 | ||
338 | int dlm_midcomms_addr(int nodeid, struct sockaddr_storage *addr, int len) | |
339 | { | |
340 | int ret, r = nodeid_hash(nodeid); | |
341 | struct midcomms_node *node; | |
489d8e55 | 342 | |
63e711b0 AA |
343 | ret = dlm_lowcomms_addr(nodeid, addr, len); |
344 | if (ret) | |
345 | return ret; | |
489d8e55 | 346 | |
63e711b0 | 347 | node = kmalloc(sizeof(*node), GFP_NOFS); |
489d8e55 | 348 | if (!node) |
63e711b0 | 349 | return -ENOMEM; |
489d8e55 AA |
350 | |
351 | node->nodeid = nodeid; | |
352 | spin_lock_init(&node->state_lock); | |
353 | spin_lock_init(&node->send_queue_lock); | |
354 | atomic_set(&node->send_queue_cnt, 0); | |
355 | INIT_LIST_HEAD(&node->send_queue); | |
356 | init_waitqueue_head(&node->shutdown_wait); | |
357 | node->users = 0; | |
358 | midcomms_node_reset(node); | |
359 | ||
360 | spin_lock(&nodes_lock); | |
489d8e55 AA |
361 | hlist_add_head_rcu(&node->hlist, &node_hash[r]); |
362 | spin_unlock(&nodes_lock); | |
5b2f981f AA |
363 | |
364 | node->debugfs = dlm_create_debug_comms_file(nodeid, node); | |
63e711b0 | 365 | return 0; |
489d8e55 AA |
366 | } |
367 | ||
368 | static int dlm_send_ack(int nodeid, uint32_t seq) | |
369 | { | |
370 | int mb_len = sizeof(struct dlm_header); | |
371 | struct dlm_header *m_header; | |
372 | struct dlm_msg *msg; | |
373 | char *ppc; | |
374 | ||
00908b33 | 375 | msg = dlm_lowcomms_new_msg(nodeid, mb_len, GFP_ATOMIC, &ppc, |
489d8e55 AA |
376 | NULL, NULL); |
377 | if (!msg) | |
378 | return -ENOMEM; | |
379 | ||
380 | m_header = (struct dlm_header *)ppc; | |
381 | ||
3428785a AA |
382 | m_header->h_version = cpu_to_le32(DLM_HEADER_MAJOR | DLM_HEADER_MINOR); |
383 | m_header->h_nodeid = cpu_to_le32(dlm_our_nodeid()); | |
384 | m_header->h_length = cpu_to_le16(mb_len); | |
489d8e55 | 385 | m_header->h_cmd = DLM_ACK; |
3428785a | 386 | m_header->u.h_seq = cpu_to_le32(seq); |
489d8e55 | 387 | |
489d8e55 AA |
388 | dlm_lowcomms_commit_msg(msg); |
389 | dlm_lowcomms_put_msg(msg); | |
390 | ||
391 | return 0; | |
392 | } | |
393 | ||
1696c75f AA |
394 | static void dlm_send_ack_threshold(struct midcomms_node *node, |
395 | uint32_t threshold) | |
396 | { | |
397 | uint32_t oval, nval; | |
398 | bool send_ack; | |
399 | ||
400 | /* let only send one user trigger threshold to send ack back */ | |
401 | do { | |
402 | oval = atomic_read(&node->ulp_delivered); | |
403 | send_ack = (oval > threshold); | |
404 | /* abort if threshold is not reached */ | |
405 | if (!send_ack) | |
406 | break; | |
407 | ||
408 | nval = 0; | |
409 | /* try to reset ulp_delivered counter */ | |
410 | } while (atomic_cmpxchg(&node->ulp_delivered, oval, nval) != oval); | |
411 | ||
412 | if (send_ack) | |
413 | dlm_send_ack(node->nodeid, atomic_read(&node->seq_next)); | |
414 | } | |
415 | ||
489d8e55 AA |
416 | static int dlm_send_fin(struct midcomms_node *node, |
417 | void (*ack_rcv)(struct midcomms_node *node)) | |
418 | { | |
419 | int mb_len = sizeof(struct dlm_header); | |
420 | struct dlm_header *m_header; | |
421 | struct dlm_mhandle *mh; | |
422 | char *ppc; | |
423 | ||
a5849636 | 424 | mh = dlm_midcomms_get_mhandle(node->nodeid, mb_len, GFP_ATOMIC, &ppc); |
489d8e55 AA |
425 | if (!mh) |
426 | return -ENOMEM; | |
427 | ||
16427211 | 428 | set_bit(DLM_NODE_FLAG_STOP_TX, &node->flags); |
489d8e55 AA |
429 | mh->ack_rcv = ack_rcv; |
430 | ||
431 | m_header = (struct dlm_header *)ppc; | |
432 | ||
3428785a AA |
433 | m_header->h_version = cpu_to_le32(DLM_HEADER_MAJOR | DLM_HEADER_MINOR); |
434 | m_header->h_nodeid = cpu_to_le32(dlm_our_nodeid()); | |
435 | m_header->h_length = cpu_to_le16(mb_len); | |
489d8e55 AA |
436 | m_header->h_cmd = DLM_FIN; |
437 | ||
489d8e55 | 438 | pr_debug("sending fin msg to node %d\n", node->nodeid); |
e01c4b7b | 439 | dlm_midcomms_commit_mhandle(mh, NULL, 0); |
489d8e55 AA |
440 | |
441 | return 0; | |
442 | } | |
443 | ||
444 | static void dlm_receive_ack(struct midcomms_node *node, uint32_t seq) | |
445 | { | |
446 | struct dlm_mhandle *mh; | |
447 | ||
448 | rcu_read_lock(); | |
449 | list_for_each_entry_rcu(mh, &node->send_queue, list) { | |
450 | if (before(mh->seq, seq)) { | |
489d8e55 AA |
451 | if (mh->ack_rcv) |
452 | mh->ack_rcv(node); | |
f5fe8d51 AA |
453 | } else { |
454 | /* send queue should be ordered */ | |
455 | break; | |
456 | } | |
457 | } | |
489d8e55 | 458 | |
dbb751ff | 459 | spin_lock_bh(&node->send_queue_lock); |
f5fe8d51 AA |
460 | list_for_each_entry_rcu(mh, &node->send_queue, list) { |
461 | if (before(mh->seq, seq)) { | |
462 | dlm_mhandle_delete(node, mh); | |
489d8e55 AA |
463 | } else { |
464 | /* send queue should be ordered */ | |
465 | break; | |
466 | } | |
467 | } | |
dbb751ff | 468 | spin_unlock_bh(&node->send_queue_lock); |
489d8e55 AA |
469 | rcu_read_unlock(); |
470 | } | |
471 | ||
472 | static void dlm_pas_fin_ack_rcv(struct midcomms_node *node) | |
473 | { | |
474 | spin_lock(&node->state_lock); | |
475 | pr_debug("receive passive fin ack from node %d with state %s\n", | |
476 | node->nodeid, dlm_state_str(node->state)); | |
477 | ||
478 | switch (node->state) { | |
479 | case DLM_LAST_ACK: | |
480 | /* DLM_CLOSED */ | |
481 | midcomms_node_reset(node); | |
482 | break; | |
483 | case DLM_CLOSED: | |
484 | /* not valid but somehow we got what we want */ | |
485 | wake_up(&node->shutdown_wait); | |
486 | break; | |
487 | default: | |
488 | spin_unlock(&node->state_lock); | |
31864097 | 489 | log_print("%s: unexpected state: %d", |
489d8e55 | 490 | __func__, node->state); |
775af207 | 491 | WARN_ON_ONCE(1); |
489d8e55 AA |
492 | return; |
493 | } | |
494 | spin_unlock(&node->state_lock); | |
495 | } | |
496 | ||
11519351 AA |
497 | static void dlm_receive_buffer_3_2_trace(uint32_t seq, |
498 | const union dlm_packet *p) | |
e01c4b7b AA |
499 | { |
500 | switch (p->header.h_cmd) { | |
501 | case DLM_MSG: | |
17827754 | 502 | trace_dlm_recv_message(dlm_our_nodeid(), seq, &p->message); |
e01c4b7b AA |
503 | break; |
504 | case DLM_RCOM: | |
17827754 | 505 | trace_dlm_recv_rcom(dlm_our_nodeid(), seq, &p->rcom); |
e01c4b7b AA |
506 | break; |
507 | default: | |
508 | break; | |
509 | } | |
510 | } | |
511 | ||
11519351 | 512 | static void dlm_midcomms_receive_buffer(const union dlm_packet *p, |
489d8e55 AA |
513 | struct midcomms_node *node, |
514 | uint32_t seq) | |
515 | { | |
d00725ca AA |
516 | bool is_expected_seq; |
517 | uint32_t oval, nval; | |
489d8e55 | 518 | |
d00725ca AA |
519 | do { |
520 | oval = atomic_read(&node->seq_next); | |
521 | is_expected_seq = (oval == seq); | |
522 | if (!is_expected_seq) | |
523 | break; | |
524 | ||
525 | nval = oval + 1; | |
526 | } while (atomic_cmpxchg(&node->seq_next, oval, nval) != oval); | |
527 | ||
528 | if (is_expected_seq) { | |
489d8e55 AA |
529 | switch (p->header.h_cmd) { |
530 | case DLM_FIN: | |
531 | spin_lock(&node->state_lock); | |
532 | pr_debug("receive fin msg from node %d with state %s\n", | |
533 | node->nodeid, dlm_state_str(node->state)); | |
534 | ||
535 | switch (node->state) { | |
536 | case DLM_ESTABLISHED: | |
d00725ca | 537 | dlm_send_ack(node->nodeid, nval); |
00908b33 | 538 | |
489d8e55 AA |
539 | /* passive shutdown DLM_LAST_ACK case 1 |
540 | * additional we check if the node is used by | |
541 | * cluster manager events at all. | |
542 | */ | |
543 | if (node->users == 0) { | |
544 | node->state = DLM_LAST_ACK; | |
545 | pr_debug("switch node %d to state %s case 1\n", | |
546 | node->nodeid, dlm_state_str(node->state)); | |
a5849636 AA |
547 | set_bit(DLM_NODE_FLAG_STOP_RX, &node->flags); |
548 | dlm_send_fin(node, dlm_pas_fin_ack_rcv); | |
ef7ef015 AA |
549 | } else { |
550 | node->state = DLM_CLOSE_WAIT; | |
551 | pr_debug("switch node %d to state %s\n", | |
552 | node->nodeid, dlm_state_str(node->state)); | |
489d8e55 AA |
553 | } |
554 | break; | |
555 | case DLM_FIN_WAIT1: | |
d00725ca | 556 | dlm_send_ack(node->nodeid, nval); |
489d8e55 | 557 | node->state = DLM_CLOSING; |
15c63db8 | 558 | set_bit(DLM_NODE_FLAG_STOP_RX, &node->flags); |
489d8e55 AA |
559 | pr_debug("switch node %d to state %s\n", |
560 | node->nodeid, dlm_state_str(node->state)); | |
561 | break; | |
562 | case DLM_FIN_WAIT2: | |
d00725ca | 563 | dlm_send_ack(node->nodeid, nval); |
489d8e55 AA |
564 | midcomms_node_reset(node); |
565 | pr_debug("switch node %d to state %s\n", | |
566 | node->nodeid, dlm_state_str(node->state)); | |
489d8e55 AA |
567 | break; |
568 | case DLM_LAST_ACK: | |
569 | /* probably remove_member caught it, do nothing */ | |
570 | break; | |
571 | default: | |
572 | spin_unlock(&node->state_lock); | |
31864097 | 573 | log_print("%s: unexpected state: %d", |
489d8e55 | 574 | __func__, node->state); |
775af207 | 575 | WARN_ON_ONCE(1); |
489d8e55 AA |
576 | return; |
577 | } | |
578 | spin_unlock(&node->state_lock); | |
489d8e55 AA |
579 | break; |
580 | default: | |
775af207 | 581 | WARN_ON_ONCE(test_bit(DLM_NODE_FLAG_STOP_RX, &node->flags)); |
e01c4b7b | 582 | dlm_receive_buffer_3_2_trace(seq, p); |
489d8e55 | 583 | dlm_receive_buffer(p, node->nodeid); |
1696c75f AA |
584 | atomic_inc(&node->ulp_delivered); |
585 | /* unlikely case to send ack back when we don't transmit */ | |
586 | dlm_send_ack_threshold(node, DLM_RECV_ACK_BACK_MSG_THRESHOLD); | |
489d8e55 AA |
587 | break; |
588 | } | |
589 | } else { | |
590 | /* retry to ack message which we already have by sending back | |
591 | * current node->seq_next number as ack. | |
592 | */ | |
d00725ca AA |
593 | if (seq < oval) |
594 | dlm_send_ack(node->nodeid, oval); | |
489d8e55 AA |
595 | |
596 | log_print_ratelimited("ignore dlm msg because seq mismatch, seq: %u, expected: %u, nodeid: %d", | |
d00725ca | 597 | seq, oval, node->nodeid); |
489d8e55 | 598 | } |
489d8e55 AA |
599 | } |
600 | ||
11519351 AA |
601 | static int dlm_opts_check_msglen(const union dlm_packet *p, uint16_t msglen, |
602 | int nodeid) | |
489d8e55 AA |
603 | { |
604 | int len = msglen; | |
605 | ||
606 | /* we only trust outer header msglen because | |
607 | * it's checked against receive buffer length. | |
608 | */ | |
609 | if (len < sizeof(struct dlm_opts)) | |
610 | return -1; | |
611 | len -= sizeof(struct dlm_opts); | |
612 | ||
613 | if (len < le16_to_cpu(p->opts.o_optlen)) | |
614 | return -1; | |
615 | len -= le16_to_cpu(p->opts.o_optlen); | |
616 | ||
617 | switch (p->opts.o_nextcmd) { | |
618 | case DLM_FIN: | |
619 | if (len < sizeof(struct dlm_header)) { | |
620 | log_print("fin too small: %d, will skip this message from node %d", | |
621 | len, nodeid); | |
622 | return -1; | |
623 | } | |
624 | ||
625 | break; | |
626 | case DLM_MSG: | |
627 | if (len < sizeof(struct dlm_message)) { | |
628 | log_print("msg too small: %d, will skip this message from node %d", | |
629 | msglen, nodeid); | |
630 | return -1; | |
631 | } | |
632 | ||
633 | break; | |
634 | case DLM_RCOM: | |
635 | if (len < sizeof(struct dlm_rcom)) { | |
636 | log_print("rcom msg too small: %d, will skip this message from node %d", | |
637 | len, nodeid); | |
638 | return -1; | |
639 | } | |
640 | ||
641 | break; | |
642 | default: | |
643 | log_print("unsupported o_nextcmd received: %u, will skip this message from node %d", | |
644 | p->opts.o_nextcmd, nodeid); | |
645 | return -1; | |
646 | } | |
647 | ||
648 | return 0; | |
649 | } | |
650 | ||
11519351 | 651 | static void dlm_midcomms_receive_buffer_3_2(const union dlm_packet *p, int nodeid) |
489d8e55 AA |
652 | { |
653 | uint16_t msglen = le16_to_cpu(p->header.h_length); | |
654 | struct midcomms_node *node; | |
655 | uint32_t seq; | |
656 | int ret, idx; | |
657 | ||
658 | idx = srcu_read_lock(&nodes_srcu); | |
63e711b0 AA |
659 | node = nodeid2node(nodeid); |
660 | if (WARN_ON_ONCE(!node)) | |
661 | goto out; | |
662 | ||
663 | switch (node->version) { | |
664 | case DLM_VERSION_NOT_SET: | |
665 | node->version = DLM_VERSION_3_2; | |
666 | wake_up(&node->shutdown_wait); | |
667 | log_print("version 0x%08x for node %d detected", DLM_VERSION_3_2, | |
668 | node->nodeid); | |
669 | ||
670 | spin_lock(&node->state_lock); | |
671 | switch (node->state) { | |
672 | case DLM_CLOSED: | |
673 | node->state = DLM_ESTABLISHED; | |
674 | pr_debug("switch node %d to state %s\n", | |
675 | node->nodeid, dlm_state_str(node->state)); | |
676 | break; | |
677 | default: | |
678 | break; | |
679 | } | |
680 | spin_unlock(&node->state_lock); | |
681 | ||
682 | break; | |
683 | case DLM_VERSION_3_2: | |
684 | break; | |
685 | default: | |
686 | log_print_ratelimited("version mismatch detected, assumed 0x%08x but node %d has 0x%08x", | |
687 | DLM_VERSION_3_2, node->nodeid, node->version); | |
489d8e55 | 688 | goto out; |
63e711b0 | 689 | } |
489d8e55 AA |
690 | |
691 | switch (p->header.h_cmd) { | |
692 | case DLM_RCOM: | |
693 | /* these rcom message we use to determine version. | |
694 | * they have their own retransmission handling and | |
695 | * are the first messages of dlm. | |
696 | * | |
697 | * length already checked. | |
698 | */ | |
14a92fd7 AA |
699 | switch (p->rcom.rc_type) { |
700 | case cpu_to_le32(DLM_RCOM_NAMES): | |
489d8e55 | 701 | fallthrough; |
14a92fd7 | 702 | case cpu_to_le32(DLM_RCOM_NAMES_REPLY): |
489d8e55 | 703 | fallthrough; |
14a92fd7 | 704 | case cpu_to_le32(DLM_RCOM_STATUS): |
489d8e55 | 705 | fallthrough; |
14a92fd7 | 706 | case cpu_to_le32(DLM_RCOM_STATUS_REPLY): |
489d8e55 AA |
707 | break; |
708 | default: | |
709 | log_print("unsupported rcom type received: %u, will skip this message from node %d", | |
710 | le32_to_cpu(p->rcom.rc_type), nodeid); | |
711 | goto out; | |
712 | } | |
713 | ||
775af207 | 714 | WARN_ON_ONCE(test_bit(DLM_NODE_FLAG_STOP_RX, &node->flags)); |
489d8e55 AA |
715 | dlm_receive_buffer(p, nodeid); |
716 | break; | |
717 | case DLM_OPTS: | |
718 | seq = le32_to_cpu(p->header.u.h_seq); | |
719 | ||
720 | ret = dlm_opts_check_msglen(p, msglen, nodeid); | |
721 | if (ret < 0) { | |
722 | log_print("opts msg too small: %u, will skip this message from node %d", | |
723 | msglen, nodeid); | |
724 | goto out; | |
725 | } | |
726 | ||
727 | p = (union dlm_packet *)((unsigned char *)p->opts.o_opts + | |
728 | le16_to_cpu(p->opts.o_optlen)); | |
729 | ||
730 | /* recheck inner msglen just if it's not garbage */ | |
731 | msglen = le16_to_cpu(p->header.h_length); | |
732 | switch (p->header.h_cmd) { | |
733 | case DLM_RCOM: | |
734 | if (msglen < sizeof(struct dlm_rcom)) { | |
735 | log_print("inner rcom msg too small: %u, will skip this message from node %d", | |
736 | msglen, nodeid); | |
737 | goto out; | |
738 | } | |
739 | ||
740 | break; | |
741 | case DLM_MSG: | |
742 | if (msglen < sizeof(struct dlm_message)) { | |
743 | log_print("inner msg too small: %u, will skip this message from node %d", | |
744 | msglen, nodeid); | |
745 | goto out; | |
746 | } | |
747 | ||
748 | break; | |
749 | case DLM_FIN: | |
750 | if (msglen < sizeof(struct dlm_header)) { | |
751 | log_print("inner fin too small: %u, will skip this message from node %d", | |
752 | msglen, nodeid); | |
753 | goto out; | |
754 | } | |
755 | ||
756 | break; | |
757 | default: | |
758 | log_print("unsupported inner h_cmd received: %u, will skip this message from node %d", | |
759 | msglen, nodeid); | |
760 | goto out; | |
761 | } | |
762 | ||
763 | dlm_midcomms_receive_buffer(p, node, seq); | |
764 | break; | |
765 | case DLM_ACK: | |
766 | seq = le32_to_cpu(p->header.u.h_seq); | |
767 | dlm_receive_ack(node, seq); | |
768 | break; | |
769 | default: | |
770 | log_print("unsupported h_cmd received: %u, will skip this message from node %d", | |
771 | p->header.h_cmd, nodeid); | |
772 | break; | |
773 | } | |
774 | ||
775 | out: | |
776 | srcu_read_unlock(&nodes_srcu, idx); | |
777 | } | |
778 | ||
63e711b0 | 779 | static void dlm_midcomms_receive_buffer_3_1(const union dlm_packet *p, int nodeid) |
a070a91c | 780 | { |
63e711b0 AA |
781 | uint16_t msglen = le16_to_cpu(p->header.h_length); |
782 | struct midcomms_node *node; | |
783 | int idx; | |
784 | ||
785 | idx = srcu_read_lock(&nodes_srcu); | |
786 | node = nodeid2node(nodeid); | |
787 | if (WARN_ON_ONCE(!node)) { | |
788 | srcu_read_unlock(&nodes_srcu, idx); | |
789 | return; | |
790 | } | |
791 | ||
489d8e55 AA |
792 | switch (node->version) { |
793 | case DLM_VERSION_NOT_SET: | |
794 | node->version = DLM_VERSION_3_1; | |
b8b750e0 | 795 | wake_up(&node->shutdown_wait); |
489d8e55 AA |
796 | log_print("version 0x%08x for node %d detected", DLM_VERSION_3_1, |
797 | node->nodeid); | |
798 | break; | |
799 | case DLM_VERSION_3_1: | |
800 | break; | |
801 | default: | |
802 | log_print_ratelimited("version mismatch detected, assumed 0x%08x but node %d has 0x%08x", | |
803 | DLM_VERSION_3_1, node->nodeid, node->version); | |
489d8e55 AA |
804 | srcu_read_unlock(&nodes_srcu, idx); |
805 | return; | |
806 | } | |
807 | srcu_read_unlock(&nodes_srcu, idx); | |
808 | ||
809 | switch (p->header.h_cmd) { | |
810 | case DLM_RCOM: | |
811 | /* length already checked */ | |
812 | break; | |
813 | case DLM_MSG: | |
814 | if (msglen < sizeof(struct dlm_message)) { | |
815 | log_print("msg too small: %u, will skip this message from node %d", | |
816 | msglen, nodeid); | |
817 | return; | |
818 | } | |
819 | ||
820 | break; | |
821 | default: | |
822 | log_print("unsupported h_cmd received: %u, will skip this message from node %d", | |
823 | p->header.h_cmd, nodeid); | |
824 | return; | |
825 | } | |
826 | ||
827 | dlm_receive_buffer(p, nodeid); | |
a070a91c AA |
828 | } |
829 | ||
dbb751ff | 830 | int dlm_validate_incoming_buffer(int nodeid, unsigned char *buf, int len) |
e7fd4179 | 831 | { |
4798cbbf AA |
832 | const unsigned char *ptr = buf; |
833 | const struct dlm_header *hd; | |
e7fd4179 | 834 | uint16_t msglen; |
4798cbbf | 835 | int ret = 0; |
e7fd4179 | 836 | |
4798cbbf AA |
837 | while (len >= sizeof(struct dlm_header)) { |
838 | hd = (struct dlm_header *)ptr; | |
839 | ||
d10a0b88 | 840 | /* no message should be more than DLM_MAX_SOCKET_BUFSIZE or |
df9e06b8 AA |
841 | * less than dlm_header size. |
842 | * | |
843 | * Some messages does not have a 8 byte length boundary yet | |
844 | * which can occur in a unaligned memory access of some dlm | |
845 | * messages. However this problem need to be fixed at the | |
846 | * sending side, for now it seems nobody run into architecture | |
847 | * related issues yet but it slows down some processing. | |
848 | * Fixing this issue should be scheduled in future by doing | |
849 | * the next major version bump. | |
4798cbbf | 850 | */ |
df9e06b8 | 851 | msglen = le16_to_cpu(hd->h_length); |
d10a0b88 | 852 | if (msglen > DLM_MAX_SOCKET_BUFSIZE || |
710176e8 AA |
853 | msglen < sizeof(struct dlm_header)) { |
854 | log_print("received invalid length header: %u from node %d, will abort message parsing", | |
855 | msglen, nodeid); | |
4798cbbf | 856 | return -EBADMSG; |
e7fd4179 | 857 | } |
e7fd4179 | 858 | |
4798cbbf AA |
859 | /* caller will take care that leftover |
860 | * will be parsed next call with more data | |
861 | */ | |
e7fd4179 DT |
862 | if (msglen > len) |
863 | break; | |
864 | ||
dbb751ff AA |
865 | ret += msglen; |
866 | len -= msglen; | |
867 | ptr += msglen; | |
868 | } | |
869 | ||
870 | return ret; | |
871 | } | |
872 | ||
873 | /* | |
874 | * Called from the low-level comms layer to process a buffer of | |
875 | * commands. | |
876 | */ | |
877 | int dlm_process_incoming_buffer(int nodeid, unsigned char *buf, int len) | |
878 | { | |
879 | const unsigned char *ptr = buf; | |
880 | const struct dlm_header *hd; | |
881 | uint16_t msglen; | |
882 | int ret = 0; | |
883 | ||
884 | while (len >= sizeof(struct dlm_header)) { | |
885 | hd = (struct dlm_header *)ptr; | |
886 | ||
887 | msglen = le16_to_cpu(hd->h_length); | |
888 | if (msglen > len) | |
889 | break; | |
890 | ||
658bd576 AA |
891 | switch (hd->h_version) { |
892 | case cpu_to_le32(DLM_VERSION_3_1): | |
11519351 | 893 | dlm_midcomms_receive_buffer_3_1((const union dlm_packet *)ptr, nodeid); |
4798cbbf | 894 | break; |
658bd576 | 895 | case cpu_to_le32(DLM_VERSION_3_2): |
11519351 | 896 | dlm_midcomms_receive_buffer_3_2((const union dlm_packet *)ptr, nodeid); |
4798cbbf AA |
897 | break; |
898 | default: | |
489d8e55 AA |
899 | log_print("received invalid version header: %u from node %d, will skip this message", |
900 | le32_to_cpu(hd->h_version), nodeid); | |
901 | break; | |
4798cbbf | 902 | } |
e7fd4179 DT |
903 | |
904 | ret += msglen; | |
e7fd4179 | 905 | len -= msglen; |
4798cbbf | 906 | ptr += msglen; |
e7fd4179 DT |
907 | } |
908 | ||
4798cbbf | 909 | return ret; |
e7fd4179 | 910 | } |
489d8e55 AA |
911 | |
912 | void dlm_midcomms_unack_msg_resend(int nodeid) | |
913 | { | |
914 | struct midcomms_node *node; | |
915 | struct dlm_mhandle *mh; | |
916 | int idx, ret; | |
917 | ||
918 | idx = srcu_read_lock(&nodes_srcu); | |
63e711b0 AA |
919 | node = nodeid2node(nodeid); |
920 | if (WARN_ON_ONCE(!node)) { | |
489d8e55 AA |
921 | srcu_read_unlock(&nodes_srcu, idx); |
922 | return; | |
923 | } | |
924 | ||
925 | /* old protocol, we don't support to retransmit on failure */ | |
926 | switch (node->version) { | |
927 | case DLM_VERSION_3_2: | |
928 | break; | |
929 | default: | |
930 | srcu_read_unlock(&nodes_srcu, idx); | |
931 | return; | |
932 | } | |
933 | ||
934 | rcu_read_lock(); | |
935 | list_for_each_entry_rcu(mh, &node->send_queue, list) { | |
936 | if (!mh->committed) | |
937 | continue; | |
938 | ||
939 | ret = dlm_lowcomms_resend_msg(mh->msg); | |
940 | if (!ret) | |
941 | log_print_ratelimited("retransmit dlm msg, seq %u, nodeid %d", | |
942 | mh->seq, node->nodeid); | |
943 | } | |
944 | rcu_read_unlock(); | |
945 | srcu_read_unlock(&nodes_srcu, idx); | |
946 | } | |
947 | ||
948 | static void dlm_fill_opts_header(struct dlm_opts *opts, uint16_t inner_len, | |
949 | uint32_t seq) | |
950 | { | |
951 | opts->o_header.h_cmd = DLM_OPTS; | |
3428785a AA |
952 | opts->o_header.h_version = cpu_to_le32(DLM_HEADER_MAJOR | DLM_HEADER_MINOR); |
953 | opts->o_header.h_nodeid = cpu_to_le32(dlm_our_nodeid()); | |
954 | opts->o_header.h_length = cpu_to_le16(DLM_MIDCOMMS_OPT_LEN + inner_len); | |
955 | opts->o_header.u.h_seq = cpu_to_le32(seq); | |
489d8e55 AA |
956 | } |
957 | ||
5c16febb | 958 | static void midcomms_new_msg_cb(void *data) |
489d8e55 | 959 | { |
5c16febb AA |
960 | struct dlm_mhandle *mh = data; |
961 | ||
489d8e55 AA |
962 | atomic_inc(&mh->node->send_queue_cnt); |
963 | ||
dbb751ff | 964 | spin_lock_bh(&mh->node->send_queue_lock); |
489d8e55 | 965 | list_add_tail_rcu(&mh->list, &mh->node->send_queue); |
dbb751ff | 966 | spin_unlock_bh(&mh->node->send_queue_lock); |
489d8e55 | 967 | |
d00725ca | 968 | mh->seq = atomic_fetch_inc(&mh->node->seq_send); |
489d8e55 AA |
969 | } |
970 | ||
971 | static struct dlm_msg *dlm_midcomms_get_msg_3_2(struct dlm_mhandle *mh, int nodeid, | |
972 | int len, gfp_t allocation, char **ppc) | |
973 | { | |
974 | struct dlm_opts *opts; | |
975 | struct dlm_msg *msg; | |
976 | ||
977 | msg = dlm_lowcomms_new_msg(nodeid, len + DLM_MIDCOMMS_OPT_LEN, | |
978 | allocation, ppc, midcomms_new_msg_cb, mh); | |
979 | if (!msg) | |
980 | return NULL; | |
981 | ||
982 | opts = (struct dlm_opts *)*ppc; | |
983 | mh->opts = opts; | |
984 | ||
985 | /* add possible options here */ | |
986 | dlm_fill_opts_header(opts, len, mh->seq); | |
987 | ||
988 | *ppc += sizeof(*opts); | |
5b787667 | 989 | mh->inner_p = (const union dlm_packet *)*ppc; |
489d8e55 AA |
990 | return msg; |
991 | } | |
992 | ||
a8449f23 AA |
993 | /* avoid false positive for nodes_srcu, unlock happens in |
994 | * dlm_midcomms_commit_mhandle which is a must call if success | |
995 | */ | |
996 | #ifndef __CHECKER__ | |
489d8e55 AA |
997 | struct dlm_mhandle *dlm_midcomms_get_mhandle(int nodeid, int len, |
998 | gfp_t allocation, char **ppc) | |
999 | { | |
1000 | struct midcomms_node *node; | |
1001 | struct dlm_mhandle *mh; | |
1002 | struct dlm_msg *msg; | |
1003 | int idx; | |
1004 | ||
1005 | idx = srcu_read_lock(&nodes_srcu); | |
63e711b0 AA |
1006 | node = nodeid2node(nodeid); |
1007 | if (WARN_ON_ONCE(!node)) | |
489d8e55 | 1008 | goto err; |
489d8e55 AA |
1009 | |
1010 | /* this is a bug, however we going on and hope it will be resolved */ | |
775af207 | 1011 | WARN_ON_ONCE(test_bit(DLM_NODE_FLAG_STOP_TX, &node->flags)); |
489d8e55 | 1012 | |
e1711fe3 | 1013 | mh = dlm_allocate_mhandle(allocation); |
489d8e55 AA |
1014 | if (!mh) |
1015 | goto err; | |
1016 | ||
6c547f26 AA |
1017 | mh->committed = false; |
1018 | mh->ack_rcv = NULL; | |
489d8e55 AA |
1019 | mh->idx = idx; |
1020 | mh->node = node; | |
1021 | ||
1022 | switch (node->version) { | |
1023 | case DLM_VERSION_3_1: | |
1024 | msg = dlm_lowcomms_new_msg(nodeid, len, allocation, ppc, | |
1025 | NULL, NULL); | |
1026 | if (!msg) { | |
6c547f26 | 1027 | dlm_free_mhandle(mh); |
489d8e55 AA |
1028 | goto err; |
1029 | } | |
1030 | ||
1031 | break; | |
1032 | case DLM_VERSION_3_2: | |
1033 | msg = dlm_midcomms_get_msg_3_2(mh, nodeid, len, allocation, | |
1034 | ppc); | |
1035 | if (!msg) { | |
6c547f26 | 1036 | dlm_free_mhandle(mh); |
489d8e55 AA |
1037 | goto err; |
1038 | } | |
1039 | ||
1696c75f AA |
1040 | /* send ack back if necessary */ |
1041 | dlm_send_ack_threshold(node, DLM_SEND_ACK_BACK_MSG_THRESHOLD); | |
489d8e55 AA |
1042 | break; |
1043 | default: | |
6c547f26 | 1044 | dlm_free_mhandle(mh); |
775af207 | 1045 | WARN_ON_ONCE(1); |
489d8e55 AA |
1046 | goto err; |
1047 | } | |
1048 | ||
1049 | mh->msg = msg; | |
1050 | ||
1051 | /* keep in mind that is a must to call | |
1052 | * dlm_midcomms_commit_msg() which releases | |
1053 | * nodes_srcu using mh->idx which is assumed | |
1054 | * here that the application will call it. | |
1055 | */ | |
1056 | return mh; | |
1057 | ||
1058 | err: | |
1059 | srcu_read_unlock(&nodes_srcu, idx); | |
1060 | return NULL; | |
1061 | } | |
a8449f23 | 1062 | #endif |
489d8e55 | 1063 | |
e01c4b7b AA |
1064 | static void dlm_midcomms_commit_msg_3_2_trace(const struct dlm_mhandle *mh, |
1065 | const void *name, int namelen) | |
1066 | { | |
1067 | switch (mh->inner_p->header.h_cmd) { | |
1068 | case DLM_MSG: | |
17827754 AA |
1069 | trace_dlm_send_message(mh->node->nodeid, mh->seq, |
1070 | &mh->inner_p->message, | |
e01c4b7b AA |
1071 | name, namelen); |
1072 | break; | |
1073 | case DLM_RCOM: | |
17827754 AA |
1074 | trace_dlm_send_rcom(mh->node->nodeid, mh->seq, |
1075 | &mh->inner_p->rcom); | |
e01c4b7b AA |
1076 | break; |
1077 | default: | |
1078 | /* nothing to trace */ | |
1079 | break; | |
1080 | } | |
1081 | } | |
1082 | ||
1083 | static void dlm_midcomms_commit_msg_3_2(struct dlm_mhandle *mh, | |
1084 | const void *name, int namelen) | |
489d8e55 AA |
1085 | { |
1086 | /* nexthdr chain for fast lookup */ | |
5b787667 | 1087 | mh->opts->o_nextcmd = mh->inner_p->header.h_cmd; |
489d8e55 | 1088 | mh->committed = true; |
e01c4b7b | 1089 | dlm_midcomms_commit_msg_3_2_trace(mh, name, namelen); |
489d8e55 AA |
1090 | dlm_lowcomms_commit_msg(mh->msg); |
1091 | } | |
1092 | ||
a8449f23 AA |
1093 | /* avoid false positive for nodes_srcu, lock was happen in |
1094 | * dlm_midcomms_get_mhandle | |
1095 | */ | |
1096 | #ifndef __CHECKER__ | |
e01c4b7b AA |
1097 | void dlm_midcomms_commit_mhandle(struct dlm_mhandle *mh, |
1098 | const void *name, int namelen) | |
489d8e55 | 1099 | { |
e01c4b7b | 1100 | |
489d8e55 AA |
1101 | switch (mh->node->version) { |
1102 | case DLM_VERSION_3_1: | |
1103 | srcu_read_unlock(&nodes_srcu, mh->idx); | |
1104 | ||
1105 | dlm_lowcomms_commit_msg(mh->msg); | |
1106 | dlm_lowcomms_put_msg(mh->msg); | |
1107 | /* mh is not part of rcu list in this case */ | |
6c547f26 | 1108 | dlm_free_mhandle(mh); |
489d8e55 AA |
1109 | break; |
1110 | case DLM_VERSION_3_2: | |
724b6bab AA |
1111 | /* held rcu read lock here, because we sending the |
1112 | * dlm message out, when we do that we could receive | |
1113 | * an ack back which releases the mhandle and we | |
1114 | * get a use after free. | |
1115 | */ | |
1116 | rcu_read_lock(); | |
e01c4b7b | 1117 | dlm_midcomms_commit_msg_3_2(mh, name, namelen); |
489d8e55 | 1118 | srcu_read_unlock(&nodes_srcu, mh->idx); |
724b6bab | 1119 | rcu_read_unlock(); |
489d8e55 AA |
1120 | break; |
1121 | default: | |
1122 | srcu_read_unlock(&nodes_srcu, mh->idx); | |
775af207 | 1123 | WARN_ON_ONCE(1); |
489d8e55 AA |
1124 | break; |
1125 | } | |
1126 | } | |
a8449f23 | 1127 | #endif |
489d8e55 AA |
1128 | |
1129 | int dlm_midcomms_start(void) | |
8b0188b0 AA |
1130 | { |
1131 | return dlm_lowcomms_start(); | |
1132 | } | |
1133 | ||
1134 | void dlm_midcomms_stop(void) | |
1135 | { | |
1136 | dlm_lowcomms_stop(); | |
1137 | } | |
1138 | ||
1139 | void dlm_midcomms_init(void) | |
489d8e55 AA |
1140 | { |
1141 | int i; | |
1142 | ||
1143 | for (i = 0; i < CONN_HASH_SIZE; i++) | |
1144 | INIT_HLIST_HEAD(&node_hash[i]); | |
1145 | ||
8b0188b0 AA |
1146 | dlm_lowcomms_init(); |
1147 | } | |
1148 | ||
63e711b0 AA |
1149 | static void midcomms_node_release(struct rcu_head *rcu) |
1150 | { | |
1151 | struct midcomms_node *node = container_of(rcu, struct midcomms_node, rcu); | |
1152 | ||
1153 | WARN_ON_ONCE(atomic_read(&node->send_queue_cnt)); | |
1154 | dlm_send_queue_flush(node); | |
1155 | kfree(node); | |
1156 | } | |
1157 | ||
8b0188b0 AA |
1158 | void dlm_midcomms_exit(void) |
1159 | { | |
63e711b0 AA |
1160 | struct midcomms_node *node; |
1161 | int i, idx; | |
1162 | ||
1163 | idx = srcu_read_lock(&nodes_srcu); | |
1164 | for (i = 0; i < CONN_HASH_SIZE; i++) { | |
1165 | hlist_for_each_entry_rcu(node, &node_hash[i], hlist) { | |
1166 | dlm_delete_debug_comms_file(node->debugfs); | |
1167 | ||
1168 | spin_lock(&nodes_lock); | |
1169 | hlist_del_rcu(&node->hlist); | |
1170 | spin_unlock(&nodes_lock); | |
1171 | ||
1172 | call_srcu(&nodes_srcu, &node->rcu, midcomms_node_release); | |
1173 | } | |
1174 | } | |
1175 | srcu_read_unlock(&nodes_srcu, idx); | |
1176 | ||
8b0188b0 | 1177 | dlm_lowcomms_exit(); |
489d8e55 AA |
1178 | } |
1179 | ||
1180 | static void dlm_act_fin_ack_rcv(struct midcomms_node *node) | |
1181 | { | |
1182 | spin_lock(&node->state_lock); | |
1183 | pr_debug("receive active fin ack from node %d with state %s\n", | |
1184 | node->nodeid, dlm_state_str(node->state)); | |
1185 | ||
1186 | switch (node->state) { | |
1187 | case DLM_FIN_WAIT1: | |
1188 | node->state = DLM_FIN_WAIT2; | |
1189 | pr_debug("switch node %d to state %s\n", | |
1190 | node->nodeid, dlm_state_str(node->state)); | |
1191 | break; | |
1192 | case DLM_CLOSING: | |
1193 | midcomms_node_reset(node); | |
1194 | pr_debug("switch node %d to state %s\n", | |
1195 | node->nodeid, dlm_state_str(node->state)); | |
489d8e55 AA |
1196 | break; |
1197 | case DLM_CLOSED: | |
1198 | /* not valid but somehow we got what we want */ | |
1199 | wake_up(&node->shutdown_wait); | |
1200 | break; | |
1201 | default: | |
1202 | spin_unlock(&node->state_lock); | |
31864097 | 1203 | log_print("%s: unexpected state: %d", |
489d8e55 | 1204 | __func__, node->state); |
775af207 | 1205 | WARN_ON_ONCE(1); |
489d8e55 AA |
1206 | return; |
1207 | } | |
1208 | spin_unlock(&node->state_lock); | |
1209 | } | |
1210 | ||
1211 | void dlm_midcomms_add_member(int nodeid) | |
1212 | { | |
1213 | struct midcomms_node *node; | |
1214 | int idx; | |
1215 | ||
489d8e55 | 1216 | idx = srcu_read_lock(&nodes_srcu); |
63e711b0 AA |
1217 | node = nodeid2node(nodeid); |
1218 | if (WARN_ON_ONCE(!node)) { | |
489d8e55 AA |
1219 | srcu_read_unlock(&nodes_srcu, idx); |
1220 | return; | |
1221 | } | |
1222 | ||
1223 | spin_lock(&node->state_lock); | |
1224 | if (!node->users) { | |
1225 | pr_debug("receive add member from node %d with state %s\n", | |
1226 | node->nodeid, dlm_state_str(node->state)); | |
1227 | switch (node->state) { | |
1228 | case DLM_ESTABLISHED: | |
1229 | break; | |
1230 | case DLM_CLOSED: | |
1231 | node->state = DLM_ESTABLISHED; | |
1232 | pr_debug("switch node %d to state %s\n", | |
1233 | node->nodeid, dlm_state_str(node->state)); | |
1234 | break; | |
1235 | default: | |
1236 | /* some invalid state passive shutdown | |
1237 | * was failed, we try to reset and | |
1238 | * hope it will go on. | |
1239 | */ | |
7d3848c0 | 1240 | log_print("reset node %d because shutdown stuck", |
489d8e55 AA |
1241 | node->nodeid); |
1242 | ||
1243 | midcomms_node_reset(node); | |
1244 | node->state = DLM_ESTABLISHED; | |
1245 | break; | |
1246 | } | |
1247 | } | |
1248 | ||
1249 | node->users++; | |
1aafd9c2 | 1250 | pr_debug("node %d users inc count %d\n", nodeid, node->users); |
489d8e55 AA |
1251 | spin_unlock(&node->state_lock); |
1252 | ||
1253 | srcu_read_unlock(&nodes_srcu, idx); | |
1254 | } | |
1255 | ||
1256 | void dlm_midcomms_remove_member(int nodeid) | |
1257 | { | |
1258 | struct midcomms_node *node; | |
1259 | int idx; | |
1260 | ||
489d8e55 | 1261 | idx = srcu_read_lock(&nodes_srcu); |
63e711b0 AA |
1262 | node = nodeid2node(nodeid); |
1263 | if (WARN_ON_ONCE(!node)) { | |
489d8e55 AA |
1264 | srcu_read_unlock(&nodes_srcu, idx); |
1265 | return; | |
1266 | } | |
1267 | ||
1268 | spin_lock(&node->state_lock); | |
1269 | node->users--; | |
1aafd9c2 | 1270 | pr_debug("node %d users dec count %d\n", nodeid, node->users); |
489d8e55 AA |
1271 | |
1272 | /* hitting users count to zero means the | |
1273 | * other side is running dlm_midcomms_stop() | |
1274 | * we meet us to have a clean disconnect. | |
1275 | */ | |
1276 | if (node->users == 0) { | |
1277 | pr_debug("receive remove member from node %d with state %s\n", | |
1278 | node->nodeid, dlm_state_str(node->state)); | |
1279 | switch (node->state) { | |
1280 | case DLM_ESTABLISHED: | |
1281 | break; | |
1282 | case DLM_CLOSE_WAIT: | |
1283 | /* passive shutdown DLM_LAST_ACK case 2 */ | |
1284 | node->state = DLM_LAST_ACK; | |
489d8e55 AA |
1285 | pr_debug("switch node %d to state %s case 2\n", |
1286 | node->nodeid, dlm_state_str(node->state)); | |
a5849636 AA |
1287 | set_bit(DLM_NODE_FLAG_STOP_RX, &node->flags); |
1288 | dlm_send_fin(node, dlm_pas_fin_ack_rcv); | |
1289 | break; | |
489d8e55 AA |
1290 | case DLM_LAST_ACK: |
1291 | /* probably receive fin caught it, do nothing */ | |
1292 | break; | |
1293 | case DLM_CLOSED: | |
1294 | /* already gone, do nothing */ | |
1295 | break; | |
1296 | default: | |
31864097 | 1297 | log_print("%s: unexpected state: %d", |
489d8e55 AA |
1298 | __func__, node->state); |
1299 | break; | |
1300 | } | |
1301 | } | |
1302 | spin_unlock(&node->state_lock); | |
1303 | ||
1304 | srcu_read_unlock(&nodes_srcu, idx); | |
489d8e55 AA |
1305 | } |
1306 | ||
b8b750e0 AA |
1307 | void dlm_midcomms_version_wait(void) |
1308 | { | |
1309 | struct midcomms_node *node; | |
1310 | int i, idx, ret; | |
1311 | ||
1312 | idx = srcu_read_lock(&nodes_srcu); | |
1313 | for (i = 0; i < CONN_HASH_SIZE; i++) { | |
1314 | hlist_for_each_entry_rcu(node, &node_hash[i], hlist) { | |
1315 | ret = wait_event_timeout(node->shutdown_wait, | |
1316 | node->version != DLM_VERSION_NOT_SET || | |
1317 | node->state == DLM_CLOSED || | |
1318 | test_bit(DLM_NODE_FLAG_CLOSE, &node->flags), | |
1319 | DLM_SHUTDOWN_TIMEOUT); | |
1320 | if (!ret || test_bit(DLM_NODE_FLAG_CLOSE, &node->flags)) | |
1321 | pr_debug("version wait timed out for node %d with state %s\n", | |
1322 | node->nodeid, dlm_state_str(node->state)); | |
1323 | } | |
1324 | } | |
1325 | srcu_read_unlock(&nodes_srcu, idx); | |
1326 | } | |
1327 | ||
489d8e55 AA |
1328 | static void midcomms_shutdown(struct midcomms_node *node) |
1329 | { | |
1330 | int ret; | |
1331 | ||
1332 | /* old protocol, we don't wait for pending operations */ | |
1333 | switch (node->version) { | |
1334 | case DLM_VERSION_3_2: | |
1335 | break; | |
1336 | default: | |
1337 | return; | |
1338 | } | |
1339 | ||
1340 | spin_lock(&node->state_lock); | |
1341 | pr_debug("receive active shutdown for node %d with state %s\n", | |
1342 | node->nodeid, dlm_state_str(node->state)); | |
1343 | switch (node->state) { | |
1344 | case DLM_ESTABLISHED: | |
1345 | node->state = DLM_FIN_WAIT1; | |
1346 | pr_debug("switch node %d to state %s case 2\n", | |
1347 | node->nodeid, dlm_state_str(node->state)); | |
a5849636 | 1348 | dlm_send_fin(node, dlm_act_fin_ack_rcv); |
489d8e55 AA |
1349 | break; |
1350 | case DLM_CLOSED: | |
1351 | /* we have what we want */ | |
54fbe0c1 | 1352 | break; |
489d8e55 AA |
1353 | default: |
1354 | /* busy to enter DLM_FIN_WAIT1, wait until passive | |
1355 | * done in shutdown_wait to enter DLM_CLOSED. | |
1356 | */ | |
1357 | break; | |
1358 | } | |
1359 | spin_unlock(&node->state_lock); | |
1360 | ||
a5849636 AA |
1361 | if (DLM_DEBUG_FENCE_TERMINATION) |
1362 | msleep(5000); | |
489d8e55 AA |
1363 | |
1364 | /* wait for other side dlm + fin */ | |
1365 | ret = wait_event_timeout(node->shutdown_wait, | |
1366 | node->state == DLM_CLOSED || | |
1367 | test_bit(DLM_NODE_FLAG_CLOSE, &node->flags), | |
1368 | DLM_SHUTDOWN_TIMEOUT); | |
63e711b0 | 1369 | if (!ret) |
489d8e55 AA |
1370 | pr_debug("active shutdown timed out for node %d with state %s\n", |
1371 | node->nodeid, dlm_state_str(node->state)); | |
54fbe0c1 AA |
1372 | else |
1373 | pr_debug("active shutdown done for node %d with state %s\n", | |
1374 | node->nodeid, dlm_state_str(node->state)); | |
489d8e55 AA |
1375 | } |
1376 | ||
1377 | void dlm_midcomms_shutdown(void) | |
1378 | { | |
1379 | struct midcomms_node *node; | |
1380 | int i, idx; | |
1381 | ||
1382 | mutex_lock(&close_lock); | |
1383 | idx = srcu_read_lock(&nodes_srcu); | |
1384 | for (i = 0; i < CONN_HASH_SIZE; i++) { | |
1385 | hlist_for_each_entry_rcu(node, &node_hash[i], hlist) { | |
1386 | midcomms_shutdown(node); | |
489d8e55 AA |
1387 | } |
1388 | } | |
1389 | srcu_read_unlock(&nodes_srcu, idx); | |
1390 | mutex_unlock(&close_lock); | |
54fbe0c1 AA |
1391 | |
1392 | dlm_lowcomms_shutdown(); | |
489d8e55 AA |
1393 | } |
1394 | ||
1395 | int dlm_midcomms_close(int nodeid) | |
1396 | { | |
1397 | struct midcomms_node *node; | |
1398 | int idx, ret; | |
1399 | ||
489d8e55 AA |
1400 | idx = srcu_read_lock(&nodes_srcu); |
1401 | /* Abort pending close/remove operation */ | |
63e711b0 | 1402 | node = nodeid2node(nodeid); |
489d8e55 AA |
1403 | if (node) { |
1404 | /* let shutdown waiters leave */ | |
1405 | set_bit(DLM_NODE_FLAG_CLOSE, &node->flags); | |
1406 | wake_up(&node->shutdown_wait); | |
1407 | } | |
1408 | srcu_read_unlock(&nodes_srcu, idx); | |
1409 | ||
1410 | synchronize_srcu(&nodes_srcu); | |
1411 | ||
489d8e55 | 1412 | mutex_lock(&close_lock); |
643f5cfa | 1413 | idx = srcu_read_lock(&nodes_srcu); |
63e711b0 | 1414 | node = nodeid2node(nodeid); |
489d8e55 | 1415 | if (!node) { |
489d8e55 | 1416 | srcu_read_unlock(&nodes_srcu, idx); |
643f5cfa | 1417 | mutex_unlock(&close_lock); |
489d8e55 AA |
1418 | return dlm_lowcomms_close(nodeid); |
1419 | } | |
1420 | ||
1421 | ret = dlm_lowcomms_close(nodeid); | |
63e711b0 AA |
1422 | dlm_delete_debug_comms_file(node->debugfs); |
1423 | ||
1424 | spin_lock(&nodes_lock); | |
1425 | hlist_del_rcu(&node->hlist); | |
1426 | spin_unlock(&nodes_lock); | |
489d8e55 | 1427 | srcu_read_unlock(&nodes_srcu, idx); |
63e711b0 AA |
1428 | |
1429 | /* wait that all readers left until flush send queue */ | |
1430 | synchronize_srcu(&nodes_srcu); | |
1431 | ||
1432 | /* drop all pending dlm messages, this is fine as | |
1433 | * this function get called when the node is fenced | |
1434 | */ | |
1435 | dlm_send_queue_flush(node); | |
1436 | ||
1437 | call_srcu(&nodes_srcu, &node->rcu, midcomms_node_release); | |
489d8e55 AA |
1438 | mutex_unlock(&close_lock); |
1439 | ||
1440 | return ret; | |
1441 | } | |
9af5b8f0 AA |
1442 | |
1443 | /* debug functionality to send raw dlm msg from user space */ | |
1444 | struct dlm_rawmsg_data { | |
1445 | struct midcomms_node *node; | |
1446 | void *buf; | |
1447 | }; | |
1448 | ||
1449 | static void midcomms_new_rawmsg_cb(void *data) | |
1450 | { | |
1451 | struct dlm_rawmsg_data *rd = data; | |
1452 | struct dlm_header *h = rd->buf; | |
1453 | ||
1454 | switch (h->h_version) { | |
1455 | case cpu_to_le32(DLM_VERSION_3_1): | |
1456 | break; | |
1457 | default: | |
1458 | switch (h->h_cmd) { | |
1459 | case DLM_OPTS: | |
1460 | if (!h->u.h_seq) | |
d00725ca | 1461 | h->u.h_seq = cpu_to_le32(atomic_fetch_inc(&rd->node->seq_send)); |
9af5b8f0 AA |
1462 | break; |
1463 | default: | |
1464 | break; | |
1465 | } | |
1466 | break; | |
1467 | } | |
1468 | } | |
1469 | ||
1470 | int dlm_midcomms_rawmsg_send(struct midcomms_node *node, void *buf, | |
1471 | int buflen) | |
1472 | { | |
1473 | struct dlm_rawmsg_data rd; | |
1474 | struct dlm_msg *msg; | |
1475 | char *msgbuf; | |
1476 | ||
1477 | rd.node = node; | |
1478 | rd.buf = buf; | |
1479 | ||
1480 | msg = dlm_lowcomms_new_msg(node->nodeid, buflen, GFP_NOFS, | |
1481 | &msgbuf, midcomms_new_rawmsg_cb, &rd); | |
1482 | if (!msg) | |
1483 | return -ENOMEM; | |
1484 | ||
1485 | memcpy(msgbuf, buf, buflen); | |
1486 | dlm_lowcomms_commit_msg(msg); | |
1487 | return 0; | |
1488 | } | |
1489 |