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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 | 138 | #include "dlm_internal.h" |
2c3fa6ae | 139 | #include "lockspace.h" |
e7fd4179 DT |
140 | #include "lowcomms.h" |
141 | #include "config.h" | |
6c547f26 | 142 | #include "memory.h" |
e7fd4179 | 143 | #include "lock.h" |
489d8e55 | 144 | #include "util.h" |
e7fd4179 DT |
145 | #include "midcomms.h" |
146 | ||
489d8e55 AA |
147 | /* init value for sequence numbers for testing purpose only e.g. overflows */ |
148 | #define DLM_SEQ_INIT 0 | |
11605353 AA |
149 | /* 5 seconds wait to sync ending of dlm */ |
150 | #define DLM_SHUTDOWN_TIMEOUT msecs_to_jiffies(5000) | |
489d8e55 AA |
151 | #define DLM_VERSION_NOT_SET 0 |
152 | ||
153 | struct midcomms_node { | |
154 | int nodeid; | |
155 | uint32_t version; | |
156 | uint32_t seq_send; | |
157 | uint32_t seq_next; | |
158 | /* These queues are unbound because we cannot drop any message in dlm. | |
159 | * We could send a fence signal for a specific node to the cluster | |
160 | * manager if queues hits some maximum value, however this handling | |
161 | * not supported yet. | |
162 | */ | |
163 | struct list_head send_queue; | |
164 | spinlock_t send_queue_lock; | |
165 | atomic_t send_queue_cnt; | |
166 | #define DLM_NODE_FLAG_CLOSE 1 | |
167 | #define DLM_NODE_FLAG_STOP_TX 2 | |
168 | #define DLM_NODE_FLAG_STOP_RX 3 | |
b97f8525 | 169 | #define DLM_NODE_ULP_DELIVERED 4 |
489d8e55 AA |
170 | unsigned long flags; |
171 | wait_queue_head_t shutdown_wait; | |
172 | ||
173 | /* dlm tcp termination state */ | |
174 | #define DLM_CLOSED 1 | |
175 | #define DLM_ESTABLISHED 2 | |
176 | #define DLM_FIN_WAIT1 3 | |
177 | #define DLM_FIN_WAIT2 4 | |
178 | #define DLM_CLOSE_WAIT 5 | |
179 | #define DLM_LAST_ACK 6 | |
180 | #define DLM_CLOSING 7 | |
181 | int state; | |
182 | spinlock_t state_lock; | |
183 | ||
184 | /* counts how many lockspaces are using this node | |
185 | * this refcount is necessary to determine if the | |
186 | * node wants to disconnect. | |
187 | */ | |
188 | int users; | |
189 | ||
5b2f981f AA |
190 | /* not protected by srcu, node_hash lifetime */ |
191 | void *debugfs; | |
192 | ||
489d8e55 AA |
193 | struct hlist_node hlist; |
194 | struct rcu_head rcu; | |
195 | }; | |
196 | ||
197 | struct dlm_mhandle { | |
5b787667 | 198 | const union dlm_packet *inner_p; |
489d8e55 AA |
199 | struct midcomms_node *node; |
200 | struct dlm_opts *opts; | |
201 | struct dlm_msg *msg; | |
202 | bool committed; | |
203 | uint32_t seq; | |
204 | ||
205 | void (*ack_rcv)(struct midcomms_node *node); | |
206 | ||
207 | /* get_mhandle/commit srcu idx exchange */ | |
208 | int idx; | |
209 | ||
210 | struct list_head list; | |
211 | struct rcu_head rcu; | |
212 | }; | |
213 | ||
214 | static struct hlist_head node_hash[CONN_HASH_SIZE]; | |
215 | static DEFINE_SPINLOCK(nodes_lock); | |
216 | DEFINE_STATIC_SRCU(nodes_srcu); | |
217 | ||
218 | /* This mutex prevents that midcomms_close() is running while | |
219 | * stop() or remove(). As I experienced invalid memory access | |
220 | * behaviours when DLM_DEBUG_FENCE_TERMINATION is enabled and | |
221 | * resetting machines. I will end in some double deletion in nodes | |
222 | * datastructure. | |
223 | */ | |
224 | static DEFINE_MUTEX(close_lock); | |
225 | ||
6c547f26 AA |
226 | struct kmem_cache *dlm_midcomms_cache_create(void) |
227 | { | |
228 | return kmem_cache_create("dlm_mhandle", sizeof(struct dlm_mhandle), | |
229 | 0, 0, NULL); | |
230 | } | |
231 | ||
489d8e55 | 232 | static inline const char *dlm_state_str(int state) |
a070a91c | 233 | { |
489d8e55 AA |
234 | switch (state) { |
235 | case DLM_CLOSED: | |
236 | return "CLOSED"; | |
237 | case DLM_ESTABLISHED: | |
238 | return "ESTABLISHED"; | |
239 | case DLM_FIN_WAIT1: | |
240 | return "FIN_WAIT1"; | |
241 | case DLM_FIN_WAIT2: | |
242 | return "FIN_WAIT2"; | |
243 | case DLM_CLOSE_WAIT: | |
244 | return "CLOSE_WAIT"; | |
245 | case DLM_LAST_ACK: | |
246 | return "LAST_ACK"; | |
247 | case DLM_CLOSING: | |
248 | return "CLOSING"; | |
249 | default: | |
250 | return "UNKNOWN"; | |
251 | } | |
a070a91c AA |
252 | } |
253 | ||
5b2f981f AA |
254 | const char *dlm_midcomms_state(struct midcomms_node *node) |
255 | { | |
256 | return dlm_state_str(node->state); | |
257 | } | |
258 | ||
259 | unsigned long dlm_midcomms_flags(struct midcomms_node *node) | |
260 | { | |
261 | return node->flags; | |
262 | } | |
263 | ||
264 | int dlm_midcomms_send_queue_cnt(struct midcomms_node *node) | |
265 | { | |
266 | return atomic_read(&node->send_queue_cnt); | |
267 | } | |
268 | ||
269 | uint32_t dlm_midcomms_version(struct midcomms_node *node) | |
270 | { | |
271 | return node->version; | |
272 | } | |
273 | ||
489d8e55 | 274 | static struct midcomms_node *__find_node(int nodeid, int r) |
a070a91c | 275 | { |
489d8e55 AA |
276 | struct midcomms_node *node; |
277 | ||
278 | hlist_for_each_entry_rcu(node, &node_hash[r], hlist) { | |
279 | if (node->nodeid == nodeid) | |
280 | return node; | |
281 | } | |
282 | ||
283 | return NULL; | |
a070a91c AA |
284 | } |
285 | ||
489d8e55 AA |
286 | static void dlm_mhandle_release(struct rcu_head *rcu) |
287 | { | |
288 | struct dlm_mhandle *mh = container_of(rcu, struct dlm_mhandle, rcu); | |
a070a91c | 289 | |
489d8e55 | 290 | dlm_lowcomms_put_msg(mh->msg); |
6c547f26 | 291 | dlm_free_mhandle(mh); |
489d8e55 | 292 | } |
a070a91c | 293 | |
f5fe8d51 AA |
294 | static void dlm_mhandle_delete(struct midcomms_node *node, |
295 | struct dlm_mhandle *mh) | |
296 | { | |
297 | list_del_rcu(&mh->list); | |
298 | atomic_dec(&node->send_queue_cnt); | |
299 | call_rcu(&mh->rcu, dlm_mhandle_release); | |
300 | } | |
301 | ||
489d8e55 | 302 | static void dlm_send_queue_flush(struct midcomms_node *node) |
a070a91c | 303 | { |
489d8e55 AA |
304 | struct dlm_mhandle *mh; |
305 | ||
306 | pr_debug("flush midcomms send queue of node %d\n", node->nodeid); | |
307 | ||
308 | rcu_read_lock(); | |
dbb751ff | 309 | spin_lock_bh(&node->send_queue_lock); |
489d8e55 | 310 | list_for_each_entry_rcu(mh, &node->send_queue, list) { |
f5fe8d51 | 311 | dlm_mhandle_delete(node, mh); |
489d8e55 | 312 | } |
dbb751ff | 313 | spin_unlock_bh(&node->send_queue_lock); |
489d8e55 | 314 | rcu_read_unlock(); |
a070a91c AA |
315 | } |
316 | ||
489d8e55 | 317 | static void midcomms_node_reset(struct midcomms_node *node) |
a070a91c | 318 | { |
489d8e55 AA |
319 | pr_debug("reset node %d\n", node->nodeid); |
320 | ||
321 | node->seq_next = DLM_SEQ_INIT; | |
322 | node->seq_send = DLM_SEQ_INIT; | |
323 | node->version = DLM_VERSION_NOT_SET; | |
324 | node->flags = 0; | |
325 | ||
326 | dlm_send_queue_flush(node); | |
327 | node->state = DLM_CLOSED; | |
328 | wake_up(&node->shutdown_wait); | |
a070a91c AA |
329 | } |
330 | ||
489d8e55 AA |
331 | static struct midcomms_node *nodeid2node(int nodeid, gfp_t alloc) |
332 | { | |
333 | struct midcomms_node *node, *tmp; | |
334 | int r = nodeid_hash(nodeid); | |
335 | ||
336 | node = __find_node(nodeid, r); | |
337 | if (node || !alloc) | |
338 | return node; | |
339 | ||
340 | node = kmalloc(sizeof(*node), alloc); | |
341 | if (!node) | |
342 | return NULL; | |
343 | ||
344 | node->nodeid = nodeid; | |
345 | spin_lock_init(&node->state_lock); | |
346 | spin_lock_init(&node->send_queue_lock); | |
347 | atomic_set(&node->send_queue_cnt, 0); | |
348 | INIT_LIST_HEAD(&node->send_queue); | |
349 | init_waitqueue_head(&node->shutdown_wait); | |
350 | node->users = 0; | |
351 | midcomms_node_reset(node); | |
352 | ||
353 | spin_lock(&nodes_lock); | |
354 | /* check again if there was somebody else | |
355 | * earlier here to add the node | |
356 | */ | |
357 | tmp = __find_node(nodeid, r); | |
358 | if (tmp) { | |
359 | spin_unlock(&nodes_lock); | |
360 | kfree(node); | |
361 | return tmp; | |
362 | } | |
363 | ||
364 | hlist_add_head_rcu(&node->hlist, &node_hash[r]); | |
365 | spin_unlock(&nodes_lock); | |
5b2f981f AA |
366 | |
367 | node->debugfs = dlm_create_debug_comms_file(nodeid, node); | |
489d8e55 AA |
368 | return node; |
369 | } | |
370 | ||
371 | static int dlm_send_ack(int nodeid, uint32_t seq) | |
372 | { | |
373 | int mb_len = sizeof(struct dlm_header); | |
374 | struct dlm_header *m_header; | |
375 | struct dlm_msg *msg; | |
376 | char *ppc; | |
377 | ||
00908b33 | 378 | msg = dlm_lowcomms_new_msg(nodeid, mb_len, GFP_ATOMIC, &ppc, |
489d8e55 AA |
379 | NULL, NULL); |
380 | if (!msg) | |
381 | return -ENOMEM; | |
382 | ||
383 | m_header = (struct dlm_header *)ppc; | |
384 | ||
3428785a AA |
385 | m_header->h_version = cpu_to_le32(DLM_HEADER_MAJOR | DLM_HEADER_MINOR); |
386 | m_header->h_nodeid = cpu_to_le32(dlm_our_nodeid()); | |
387 | m_header->h_length = cpu_to_le16(mb_len); | |
489d8e55 | 388 | m_header->h_cmd = DLM_ACK; |
3428785a | 389 | m_header->u.h_seq = cpu_to_le32(seq); |
489d8e55 | 390 | |
489d8e55 AA |
391 | dlm_lowcomms_commit_msg(msg); |
392 | dlm_lowcomms_put_msg(msg); | |
393 | ||
394 | return 0; | |
395 | } | |
396 | ||
397 | static int dlm_send_fin(struct midcomms_node *node, | |
398 | void (*ack_rcv)(struct midcomms_node *node)) | |
399 | { | |
400 | int mb_len = sizeof(struct dlm_header); | |
401 | struct dlm_header *m_header; | |
402 | struct dlm_mhandle *mh; | |
403 | char *ppc; | |
404 | ||
a5849636 | 405 | mh = dlm_midcomms_get_mhandle(node->nodeid, mb_len, GFP_ATOMIC, &ppc); |
489d8e55 AA |
406 | if (!mh) |
407 | return -ENOMEM; | |
408 | ||
16427211 | 409 | set_bit(DLM_NODE_FLAG_STOP_TX, &node->flags); |
489d8e55 AA |
410 | mh->ack_rcv = ack_rcv; |
411 | ||
412 | m_header = (struct dlm_header *)ppc; | |
413 | ||
3428785a AA |
414 | m_header->h_version = cpu_to_le32(DLM_HEADER_MAJOR | DLM_HEADER_MINOR); |
415 | m_header->h_nodeid = cpu_to_le32(dlm_our_nodeid()); | |
416 | m_header->h_length = cpu_to_le16(mb_len); | |
489d8e55 AA |
417 | m_header->h_cmd = DLM_FIN; |
418 | ||
489d8e55 | 419 | pr_debug("sending fin msg to node %d\n", node->nodeid); |
e01c4b7b | 420 | dlm_midcomms_commit_mhandle(mh, NULL, 0); |
489d8e55 AA |
421 | |
422 | return 0; | |
423 | } | |
424 | ||
425 | static void dlm_receive_ack(struct midcomms_node *node, uint32_t seq) | |
426 | { | |
427 | struct dlm_mhandle *mh; | |
428 | ||
429 | rcu_read_lock(); | |
430 | list_for_each_entry_rcu(mh, &node->send_queue, list) { | |
431 | if (before(mh->seq, seq)) { | |
489d8e55 AA |
432 | if (mh->ack_rcv) |
433 | mh->ack_rcv(node); | |
f5fe8d51 AA |
434 | } else { |
435 | /* send queue should be ordered */ | |
436 | break; | |
437 | } | |
438 | } | |
489d8e55 | 439 | |
dbb751ff | 440 | spin_lock_bh(&node->send_queue_lock); |
f5fe8d51 AA |
441 | list_for_each_entry_rcu(mh, &node->send_queue, list) { |
442 | if (before(mh->seq, seq)) { | |
443 | dlm_mhandle_delete(node, mh); | |
489d8e55 AA |
444 | } else { |
445 | /* send queue should be ordered */ | |
446 | break; | |
447 | } | |
448 | } | |
dbb751ff | 449 | spin_unlock_bh(&node->send_queue_lock); |
489d8e55 AA |
450 | rcu_read_unlock(); |
451 | } | |
452 | ||
453 | static void dlm_pas_fin_ack_rcv(struct midcomms_node *node) | |
454 | { | |
455 | spin_lock(&node->state_lock); | |
456 | pr_debug("receive passive fin ack from node %d with state %s\n", | |
457 | node->nodeid, dlm_state_str(node->state)); | |
458 | ||
459 | switch (node->state) { | |
460 | case DLM_LAST_ACK: | |
461 | /* DLM_CLOSED */ | |
462 | midcomms_node_reset(node); | |
463 | break; | |
464 | case DLM_CLOSED: | |
465 | /* not valid but somehow we got what we want */ | |
466 | wake_up(&node->shutdown_wait); | |
467 | break; | |
468 | default: | |
469 | spin_unlock(&node->state_lock); | |
31864097 | 470 | log_print("%s: unexpected state: %d", |
489d8e55 | 471 | __func__, node->state); |
775af207 | 472 | WARN_ON_ONCE(1); |
489d8e55 AA |
473 | return; |
474 | } | |
475 | spin_unlock(&node->state_lock); | |
476 | } | |
477 | ||
e01c4b7b AA |
478 | static void dlm_receive_buffer_3_2_trace(uint32_t seq, union dlm_packet *p) |
479 | { | |
480 | switch (p->header.h_cmd) { | |
481 | case DLM_MSG: | |
17827754 | 482 | trace_dlm_recv_message(dlm_our_nodeid(), seq, &p->message); |
e01c4b7b AA |
483 | break; |
484 | case DLM_RCOM: | |
17827754 | 485 | trace_dlm_recv_rcom(dlm_our_nodeid(), seq, &p->rcom); |
e01c4b7b AA |
486 | break; |
487 | default: | |
488 | break; | |
489 | } | |
490 | } | |
491 | ||
489d8e55 AA |
492 | static void dlm_midcomms_receive_buffer(union dlm_packet *p, |
493 | struct midcomms_node *node, | |
494 | uint32_t seq) | |
495 | { | |
496 | if (seq == node->seq_next) { | |
497 | node->seq_next++; | |
489d8e55 AA |
498 | |
499 | switch (p->header.h_cmd) { | |
500 | case DLM_FIN: | |
501 | spin_lock(&node->state_lock); | |
502 | pr_debug("receive fin msg from node %d with state %s\n", | |
503 | node->nodeid, dlm_state_str(node->state)); | |
504 | ||
505 | switch (node->state) { | |
506 | case DLM_ESTABLISHED: | |
00908b33 AA |
507 | dlm_send_ack(node->nodeid, node->seq_next); |
508 | ||
489d8e55 AA |
509 | /* passive shutdown DLM_LAST_ACK case 1 |
510 | * additional we check if the node is used by | |
511 | * cluster manager events at all. | |
512 | */ | |
513 | if (node->users == 0) { | |
514 | node->state = DLM_LAST_ACK; | |
515 | pr_debug("switch node %d to state %s case 1\n", | |
516 | node->nodeid, dlm_state_str(node->state)); | |
a5849636 AA |
517 | set_bit(DLM_NODE_FLAG_STOP_RX, &node->flags); |
518 | dlm_send_fin(node, dlm_pas_fin_ack_rcv); | |
ef7ef015 AA |
519 | } else { |
520 | node->state = DLM_CLOSE_WAIT; | |
521 | pr_debug("switch node %d to state %s\n", | |
522 | node->nodeid, dlm_state_str(node->state)); | |
489d8e55 AA |
523 | } |
524 | break; | |
525 | case DLM_FIN_WAIT1: | |
00908b33 | 526 | dlm_send_ack(node->nodeid, node->seq_next); |
489d8e55 | 527 | node->state = DLM_CLOSING; |
15c63db8 | 528 | set_bit(DLM_NODE_FLAG_STOP_RX, &node->flags); |
489d8e55 AA |
529 | pr_debug("switch node %d to state %s\n", |
530 | node->nodeid, dlm_state_str(node->state)); | |
531 | break; | |
532 | case DLM_FIN_WAIT2: | |
00908b33 | 533 | dlm_send_ack(node->nodeid, node->seq_next); |
489d8e55 AA |
534 | midcomms_node_reset(node); |
535 | pr_debug("switch node %d to state %s\n", | |
536 | node->nodeid, dlm_state_str(node->state)); | |
489d8e55 AA |
537 | break; |
538 | case DLM_LAST_ACK: | |
539 | /* probably remove_member caught it, do nothing */ | |
540 | break; | |
541 | default: | |
542 | spin_unlock(&node->state_lock); | |
31864097 | 543 | log_print("%s: unexpected state: %d", |
489d8e55 | 544 | __func__, node->state); |
775af207 | 545 | WARN_ON_ONCE(1); |
489d8e55 AA |
546 | return; |
547 | } | |
548 | spin_unlock(&node->state_lock); | |
489d8e55 AA |
549 | break; |
550 | default: | |
775af207 | 551 | WARN_ON_ONCE(test_bit(DLM_NODE_FLAG_STOP_RX, &node->flags)); |
e01c4b7b | 552 | dlm_receive_buffer_3_2_trace(seq, p); |
489d8e55 | 553 | dlm_receive_buffer(p, node->nodeid); |
b97f8525 | 554 | set_bit(DLM_NODE_ULP_DELIVERED, &node->flags); |
489d8e55 AA |
555 | break; |
556 | } | |
557 | } else { | |
558 | /* retry to ack message which we already have by sending back | |
559 | * current node->seq_next number as ack. | |
560 | */ | |
561 | if (seq < node->seq_next) | |
562 | dlm_send_ack(node->nodeid, node->seq_next); | |
563 | ||
564 | log_print_ratelimited("ignore dlm msg because seq mismatch, seq: %u, expected: %u, nodeid: %d", | |
565 | seq, node->seq_next, node->nodeid); | |
566 | } | |
489d8e55 AA |
567 | } |
568 | ||
569 | static struct midcomms_node * | |
570 | dlm_midcomms_recv_node_lookup(int nodeid, const union dlm_packet *p, | |
571 | uint16_t msglen, int (*cb)(struct midcomms_node *node)) | |
572 | { | |
573 | struct midcomms_node *node = NULL; | |
574 | gfp_t allocation = 0; | |
575 | int ret; | |
576 | ||
577 | switch (p->header.h_cmd) { | |
578 | case DLM_RCOM: | |
579 | if (msglen < sizeof(struct dlm_rcom)) { | |
580 | log_print("rcom msg too small: %u, will skip this message from node %d", | |
581 | msglen, nodeid); | |
582 | return NULL; | |
583 | } | |
584 | ||
14a92fd7 AA |
585 | switch (p->rcom.rc_type) { |
586 | case cpu_to_le32(DLM_RCOM_NAMES): | |
489d8e55 | 587 | fallthrough; |
14a92fd7 | 588 | case cpu_to_le32(DLM_RCOM_NAMES_REPLY): |
489d8e55 | 589 | fallthrough; |
14a92fd7 | 590 | case cpu_to_le32(DLM_RCOM_STATUS): |
489d8e55 | 591 | fallthrough; |
14a92fd7 | 592 | case cpu_to_le32(DLM_RCOM_STATUS_REPLY): |
489d8e55 AA |
593 | node = nodeid2node(nodeid, 0); |
594 | if (node) { | |
595 | spin_lock(&node->state_lock); | |
596 | if (node->state != DLM_ESTABLISHED) | |
597 | pr_debug("receive begin RCOM msg from node %d with state %s\n", | |
598 | node->nodeid, dlm_state_str(node->state)); | |
599 | ||
600 | switch (node->state) { | |
601 | case DLM_CLOSED: | |
602 | node->state = DLM_ESTABLISHED; | |
603 | pr_debug("switch node %d to state %s\n", | |
604 | node->nodeid, dlm_state_str(node->state)); | |
605 | break; | |
606 | case DLM_ESTABLISHED: | |
607 | break; | |
608 | default: | |
89835b06 AA |
609 | spin_unlock(&node->state_lock); |
610 | return NULL; | |
489d8e55 AA |
611 | } |
612 | spin_unlock(&node->state_lock); | |
613 | } | |
614 | ||
615 | allocation = GFP_NOFS; | |
616 | break; | |
617 | default: | |
618 | break; | |
619 | } | |
620 | ||
621 | break; | |
622 | default: | |
623 | break; | |
624 | } | |
625 | ||
626 | node = nodeid2node(nodeid, allocation); | |
627 | if (!node) { | |
957adb68 AA |
628 | switch (p->header.h_cmd) { |
629 | case DLM_OPTS: | |
630 | if (msglen < sizeof(struct dlm_opts)) { | |
631 | log_print("opts msg too small: %u, will skip this message from node %d", | |
632 | msglen, nodeid); | |
633 | return NULL; | |
634 | } | |
635 | ||
636 | log_print_ratelimited("received dlm opts message nextcmd %d from node %d in an invalid sequence", | |
637 | p->opts.o_nextcmd, nodeid); | |
638 | break; | |
639 | default: | |
640 | log_print_ratelimited("received dlm message cmd %d from node %d in an invalid sequence", | |
641 | p->header.h_cmd, nodeid); | |
642 | break; | |
643 | } | |
644 | ||
489d8e55 AA |
645 | return NULL; |
646 | } | |
647 | ||
648 | ret = cb(node); | |
649 | if (ret < 0) | |
650 | return NULL; | |
651 | ||
652 | return node; | |
653 | } | |
654 | ||
655 | static int dlm_midcomms_version_check_3_2(struct midcomms_node *node) | |
656 | { | |
657 | switch (node->version) { | |
658 | case DLM_VERSION_NOT_SET: | |
659 | node->version = DLM_VERSION_3_2; | |
b8b750e0 | 660 | wake_up(&node->shutdown_wait); |
489d8e55 AA |
661 | log_print("version 0x%08x for node %d detected", DLM_VERSION_3_2, |
662 | node->nodeid); | |
663 | break; | |
664 | case DLM_VERSION_3_2: | |
665 | break; | |
666 | default: | |
667 | log_print_ratelimited("version mismatch detected, assumed 0x%08x but node %d has 0x%08x", | |
668 | DLM_VERSION_3_2, node->nodeid, node->version); | |
669 | return -1; | |
670 | } | |
671 | ||
672 | return 0; | |
673 | } | |
674 | ||
675 | static int dlm_opts_check_msglen(union dlm_packet *p, uint16_t msglen, int nodeid) | |
676 | { | |
677 | int len = msglen; | |
678 | ||
679 | /* we only trust outer header msglen because | |
680 | * it's checked against receive buffer length. | |
681 | */ | |
682 | if (len < sizeof(struct dlm_opts)) | |
683 | return -1; | |
684 | len -= sizeof(struct dlm_opts); | |
685 | ||
686 | if (len < le16_to_cpu(p->opts.o_optlen)) | |
687 | return -1; | |
688 | len -= le16_to_cpu(p->opts.o_optlen); | |
689 | ||
690 | switch (p->opts.o_nextcmd) { | |
691 | case DLM_FIN: | |
692 | if (len < sizeof(struct dlm_header)) { | |
693 | log_print("fin too small: %d, will skip this message from node %d", | |
694 | len, nodeid); | |
695 | return -1; | |
696 | } | |
697 | ||
698 | break; | |
699 | case DLM_MSG: | |
700 | if (len < sizeof(struct dlm_message)) { | |
701 | log_print("msg too small: %d, will skip this message from node %d", | |
702 | msglen, nodeid); | |
703 | return -1; | |
704 | } | |
705 | ||
706 | break; | |
707 | case DLM_RCOM: | |
708 | if (len < sizeof(struct dlm_rcom)) { | |
709 | log_print("rcom msg too small: %d, will skip this message from node %d", | |
710 | len, nodeid); | |
711 | return -1; | |
712 | } | |
713 | ||
714 | break; | |
715 | default: | |
716 | log_print("unsupported o_nextcmd received: %u, will skip this message from node %d", | |
717 | p->opts.o_nextcmd, nodeid); | |
718 | return -1; | |
719 | } | |
720 | ||
721 | return 0; | |
722 | } | |
723 | ||
724 | static void dlm_midcomms_receive_buffer_3_2(union dlm_packet *p, int nodeid) | |
725 | { | |
726 | uint16_t msglen = le16_to_cpu(p->header.h_length); | |
727 | struct midcomms_node *node; | |
728 | uint32_t seq; | |
729 | int ret, idx; | |
730 | ||
731 | idx = srcu_read_lock(&nodes_srcu); | |
732 | node = dlm_midcomms_recv_node_lookup(nodeid, p, msglen, | |
733 | dlm_midcomms_version_check_3_2); | |
734 | if (!node) | |
735 | goto out; | |
736 | ||
737 | switch (p->header.h_cmd) { | |
738 | case DLM_RCOM: | |
739 | /* these rcom message we use to determine version. | |
740 | * they have their own retransmission handling and | |
741 | * are the first messages of dlm. | |
742 | * | |
743 | * length already checked. | |
744 | */ | |
14a92fd7 AA |
745 | switch (p->rcom.rc_type) { |
746 | case cpu_to_le32(DLM_RCOM_NAMES): | |
489d8e55 | 747 | fallthrough; |
14a92fd7 | 748 | case cpu_to_le32(DLM_RCOM_NAMES_REPLY): |
489d8e55 | 749 | fallthrough; |
14a92fd7 | 750 | case cpu_to_le32(DLM_RCOM_STATUS): |
489d8e55 | 751 | fallthrough; |
14a92fd7 | 752 | case cpu_to_le32(DLM_RCOM_STATUS_REPLY): |
489d8e55 AA |
753 | break; |
754 | default: | |
755 | log_print("unsupported rcom type received: %u, will skip this message from node %d", | |
756 | le32_to_cpu(p->rcom.rc_type), nodeid); | |
757 | goto out; | |
758 | } | |
759 | ||
775af207 | 760 | WARN_ON_ONCE(test_bit(DLM_NODE_FLAG_STOP_RX, &node->flags)); |
489d8e55 AA |
761 | dlm_receive_buffer(p, nodeid); |
762 | break; | |
763 | case DLM_OPTS: | |
764 | seq = le32_to_cpu(p->header.u.h_seq); | |
765 | ||
766 | ret = dlm_opts_check_msglen(p, msglen, nodeid); | |
767 | if (ret < 0) { | |
768 | log_print("opts msg too small: %u, will skip this message from node %d", | |
769 | msglen, nodeid); | |
770 | goto out; | |
771 | } | |
772 | ||
773 | p = (union dlm_packet *)((unsigned char *)p->opts.o_opts + | |
774 | le16_to_cpu(p->opts.o_optlen)); | |
775 | ||
776 | /* recheck inner msglen just if it's not garbage */ | |
777 | msglen = le16_to_cpu(p->header.h_length); | |
778 | switch (p->header.h_cmd) { | |
779 | case DLM_RCOM: | |
780 | if (msglen < sizeof(struct dlm_rcom)) { | |
781 | log_print("inner rcom msg too small: %u, will skip this message from node %d", | |
782 | msglen, nodeid); | |
783 | goto out; | |
784 | } | |
785 | ||
786 | break; | |
787 | case DLM_MSG: | |
788 | if (msglen < sizeof(struct dlm_message)) { | |
789 | log_print("inner msg too small: %u, will skip this message from node %d", | |
790 | msglen, nodeid); | |
791 | goto out; | |
792 | } | |
793 | ||
794 | break; | |
795 | case DLM_FIN: | |
796 | if (msglen < sizeof(struct dlm_header)) { | |
797 | log_print("inner fin too small: %u, will skip this message from node %d", | |
798 | msglen, nodeid); | |
799 | goto out; | |
800 | } | |
801 | ||
802 | break; | |
803 | default: | |
804 | log_print("unsupported inner h_cmd received: %u, will skip this message from node %d", | |
805 | msglen, nodeid); | |
806 | goto out; | |
807 | } | |
808 | ||
809 | dlm_midcomms_receive_buffer(p, node, seq); | |
810 | break; | |
811 | case DLM_ACK: | |
812 | seq = le32_to_cpu(p->header.u.h_seq); | |
813 | dlm_receive_ack(node, seq); | |
814 | break; | |
815 | default: | |
816 | log_print("unsupported h_cmd received: %u, will skip this message from node %d", | |
817 | p->header.h_cmd, nodeid); | |
818 | break; | |
819 | } | |
820 | ||
821 | out: | |
822 | srcu_read_unlock(&nodes_srcu, idx); | |
823 | } | |
824 | ||
825 | static int dlm_midcomms_version_check_3_1(struct midcomms_node *node) | |
a070a91c | 826 | { |
489d8e55 AA |
827 | switch (node->version) { |
828 | case DLM_VERSION_NOT_SET: | |
829 | node->version = DLM_VERSION_3_1; | |
b8b750e0 | 830 | wake_up(&node->shutdown_wait); |
489d8e55 AA |
831 | log_print("version 0x%08x for node %d detected", DLM_VERSION_3_1, |
832 | node->nodeid); | |
833 | break; | |
834 | case DLM_VERSION_3_1: | |
835 | break; | |
836 | default: | |
837 | log_print_ratelimited("version mismatch detected, assumed 0x%08x but node %d has 0x%08x", | |
838 | DLM_VERSION_3_1, node->nodeid, node->version); | |
839 | return -1; | |
840 | } | |
841 | ||
842 | return 0; | |
843 | } | |
844 | ||
845 | static void dlm_midcomms_receive_buffer_3_1(union dlm_packet *p, int nodeid) | |
846 | { | |
847 | uint16_t msglen = le16_to_cpu(p->header.h_length); | |
848 | struct midcomms_node *node; | |
849 | int idx; | |
850 | ||
851 | idx = srcu_read_lock(&nodes_srcu); | |
852 | node = dlm_midcomms_recv_node_lookup(nodeid, p, msglen, | |
853 | dlm_midcomms_version_check_3_1); | |
854 | if (!node) { | |
855 | srcu_read_unlock(&nodes_srcu, idx); | |
856 | return; | |
857 | } | |
858 | srcu_read_unlock(&nodes_srcu, idx); | |
859 | ||
860 | switch (p->header.h_cmd) { | |
861 | case DLM_RCOM: | |
862 | /* length already checked */ | |
863 | break; | |
864 | case DLM_MSG: | |
865 | if (msglen < sizeof(struct dlm_message)) { | |
866 | log_print("msg too small: %u, will skip this message from node %d", | |
867 | msglen, nodeid); | |
868 | return; | |
869 | } | |
870 | ||
871 | break; | |
872 | default: | |
873 | log_print("unsupported h_cmd received: %u, will skip this message from node %d", | |
874 | p->header.h_cmd, nodeid); | |
875 | return; | |
876 | } | |
877 | ||
878 | dlm_receive_buffer(p, nodeid); | |
a070a91c AA |
879 | } |
880 | ||
dbb751ff | 881 | int dlm_validate_incoming_buffer(int nodeid, unsigned char *buf, int len) |
e7fd4179 | 882 | { |
4798cbbf AA |
883 | const unsigned char *ptr = buf; |
884 | const struct dlm_header *hd; | |
e7fd4179 | 885 | uint16_t msglen; |
4798cbbf | 886 | int ret = 0; |
e7fd4179 | 887 | |
4798cbbf AA |
888 | while (len >= sizeof(struct dlm_header)) { |
889 | hd = (struct dlm_header *)ptr; | |
890 | ||
d10a0b88 | 891 | /* no message should be more than DLM_MAX_SOCKET_BUFSIZE or |
df9e06b8 AA |
892 | * less than dlm_header size. |
893 | * | |
894 | * Some messages does not have a 8 byte length boundary yet | |
895 | * which can occur in a unaligned memory access of some dlm | |
896 | * messages. However this problem need to be fixed at the | |
897 | * sending side, for now it seems nobody run into architecture | |
898 | * related issues yet but it slows down some processing. | |
899 | * Fixing this issue should be scheduled in future by doing | |
900 | * the next major version bump. | |
4798cbbf | 901 | */ |
df9e06b8 | 902 | msglen = le16_to_cpu(hd->h_length); |
d10a0b88 | 903 | if (msglen > DLM_MAX_SOCKET_BUFSIZE || |
710176e8 AA |
904 | msglen < sizeof(struct dlm_header)) { |
905 | log_print("received invalid length header: %u from node %d, will abort message parsing", | |
906 | msglen, nodeid); | |
4798cbbf | 907 | return -EBADMSG; |
e7fd4179 | 908 | } |
e7fd4179 | 909 | |
4798cbbf AA |
910 | /* caller will take care that leftover |
911 | * will be parsed next call with more data | |
912 | */ | |
e7fd4179 DT |
913 | if (msglen > len) |
914 | break; | |
915 | ||
dbb751ff AA |
916 | ret += msglen; |
917 | len -= msglen; | |
918 | ptr += msglen; | |
919 | } | |
920 | ||
921 | return ret; | |
922 | } | |
923 | ||
924 | /* | |
925 | * Called from the low-level comms layer to process a buffer of | |
926 | * commands. | |
927 | */ | |
928 | int dlm_process_incoming_buffer(int nodeid, unsigned char *buf, int len) | |
929 | { | |
930 | const unsigned char *ptr = buf; | |
931 | const struct dlm_header *hd; | |
932 | uint16_t msglen; | |
933 | int ret = 0; | |
934 | ||
935 | while (len >= sizeof(struct dlm_header)) { | |
936 | hd = (struct dlm_header *)ptr; | |
937 | ||
938 | msglen = le16_to_cpu(hd->h_length); | |
939 | if (msglen > len) | |
940 | break; | |
941 | ||
658bd576 AA |
942 | switch (hd->h_version) { |
943 | case cpu_to_le32(DLM_VERSION_3_1): | |
489d8e55 | 944 | dlm_midcomms_receive_buffer_3_1((union dlm_packet *)ptr, nodeid); |
4798cbbf | 945 | break; |
658bd576 | 946 | case cpu_to_le32(DLM_VERSION_3_2): |
489d8e55 | 947 | dlm_midcomms_receive_buffer_3_2((union dlm_packet *)ptr, nodeid); |
4798cbbf AA |
948 | break; |
949 | default: | |
489d8e55 AA |
950 | log_print("received invalid version header: %u from node %d, will skip this message", |
951 | le32_to_cpu(hd->h_version), nodeid); | |
952 | break; | |
4798cbbf | 953 | } |
e7fd4179 DT |
954 | |
955 | ret += msglen; | |
e7fd4179 | 956 | len -= msglen; |
4798cbbf | 957 | ptr += msglen; |
e7fd4179 DT |
958 | } |
959 | ||
4798cbbf | 960 | return ret; |
e7fd4179 | 961 | } |
489d8e55 | 962 | |
b97f8525 AA |
963 | void dlm_midcomms_receive_done(int nodeid) |
964 | { | |
965 | struct midcomms_node *node; | |
966 | int idx; | |
967 | ||
968 | idx = srcu_read_lock(&nodes_srcu); | |
969 | node = nodeid2node(nodeid, 0); | |
970 | if (!node) { | |
971 | srcu_read_unlock(&nodes_srcu, idx); | |
972 | return; | |
973 | } | |
974 | ||
975 | /* old protocol, we do nothing */ | |
976 | switch (node->version) { | |
977 | case DLM_VERSION_3_2: | |
978 | break; | |
979 | default: | |
980 | srcu_read_unlock(&nodes_srcu, idx); | |
981 | return; | |
982 | } | |
983 | ||
984 | /* do nothing if we didn't delivered stateful to ulp */ | |
985 | if (!test_and_clear_bit(DLM_NODE_ULP_DELIVERED, | |
986 | &node->flags)) { | |
987 | srcu_read_unlock(&nodes_srcu, idx); | |
988 | return; | |
989 | } | |
990 | ||
991 | spin_lock(&node->state_lock); | |
992 | /* we only ack if state is ESTABLISHED */ | |
993 | switch (node->state) { | |
994 | case DLM_ESTABLISHED: | |
995 | spin_unlock(&node->state_lock); | |
996 | dlm_send_ack(node->nodeid, node->seq_next); | |
997 | break; | |
998 | default: | |
999 | spin_unlock(&node->state_lock); | |
1000 | /* do nothing FIN has it's own ack send */ | |
1001 | break; | |
c8b9f34e | 1002 | } |
b97f8525 AA |
1003 | srcu_read_unlock(&nodes_srcu, idx); |
1004 | } | |
1005 | ||
489d8e55 AA |
1006 | void dlm_midcomms_unack_msg_resend(int nodeid) |
1007 | { | |
1008 | struct midcomms_node *node; | |
1009 | struct dlm_mhandle *mh; | |
1010 | int idx, ret; | |
1011 | ||
1012 | idx = srcu_read_lock(&nodes_srcu); | |
1013 | node = nodeid2node(nodeid, 0); | |
1014 | if (!node) { | |
1015 | srcu_read_unlock(&nodes_srcu, idx); | |
1016 | return; | |
1017 | } | |
1018 | ||
1019 | /* old protocol, we don't support to retransmit on failure */ | |
1020 | switch (node->version) { | |
1021 | case DLM_VERSION_3_2: | |
1022 | break; | |
1023 | default: | |
1024 | srcu_read_unlock(&nodes_srcu, idx); | |
1025 | return; | |
1026 | } | |
1027 | ||
1028 | rcu_read_lock(); | |
1029 | list_for_each_entry_rcu(mh, &node->send_queue, list) { | |
1030 | if (!mh->committed) | |
1031 | continue; | |
1032 | ||
1033 | ret = dlm_lowcomms_resend_msg(mh->msg); | |
1034 | if (!ret) | |
1035 | log_print_ratelimited("retransmit dlm msg, seq %u, nodeid %d", | |
1036 | mh->seq, node->nodeid); | |
1037 | } | |
1038 | rcu_read_unlock(); | |
1039 | srcu_read_unlock(&nodes_srcu, idx); | |
1040 | } | |
1041 | ||
1042 | static void dlm_fill_opts_header(struct dlm_opts *opts, uint16_t inner_len, | |
1043 | uint32_t seq) | |
1044 | { | |
1045 | opts->o_header.h_cmd = DLM_OPTS; | |
3428785a AA |
1046 | opts->o_header.h_version = cpu_to_le32(DLM_HEADER_MAJOR | DLM_HEADER_MINOR); |
1047 | opts->o_header.h_nodeid = cpu_to_le32(dlm_our_nodeid()); | |
1048 | opts->o_header.h_length = cpu_to_le16(DLM_MIDCOMMS_OPT_LEN + inner_len); | |
1049 | opts->o_header.u.h_seq = cpu_to_le32(seq); | |
489d8e55 AA |
1050 | } |
1051 | ||
5c16febb | 1052 | static void midcomms_new_msg_cb(void *data) |
489d8e55 | 1053 | { |
5c16febb AA |
1054 | struct dlm_mhandle *mh = data; |
1055 | ||
489d8e55 AA |
1056 | atomic_inc(&mh->node->send_queue_cnt); |
1057 | ||
dbb751ff | 1058 | spin_lock_bh(&mh->node->send_queue_lock); |
489d8e55 | 1059 | list_add_tail_rcu(&mh->list, &mh->node->send_queue); |
dbb751ff | 1060 | spin_unlock_bh(&mh->node->send_queue_lock); |
489d8e55 AA |
1061 | |
1062 | mh->seq = mh->node->seq_send++; | |
1063 | } | |
1064 | ||
1065 | static struct dlm_msg *dlm_midcomms_get_msg_3_2(struct dlm_mhandle *mh, int nodeid, | |
1066 | int len, gfp_t allocation, char **ppc) | |
1067 | { | |
1068 | struct dlm_opts *opts; | |
1069 | struct dlm_msg *msg; | |
1070 | ||
1071 | msg = dlm_lowcomms_new_msg(nodeid, len + DLM_MIDCOMMS_OPT_LEN, | |
1072 | allocation, ppc, midcomms_new_msg_cb, mh); | |
1073 | if (!msg) | |
1074 | return NULL; | |
1075 | ||
1076 | opts = (struct dlm_opts *)*ppc; | |
1077 | mh->opts = opts; | |
1078 | ||
1079 | /* add possible options here */ | |
1080 | dlm_fill_opts_header(opts, len, mh->seq); | |
1081 | ||
1082 | *ppc += sizeof(*opts); | |
5b787667 | 1083 | mh->inner_p = (const union dlm_packet *)*ppc; |
489d8e55 AA |
1084 | return msg; |
1085 | } | |
1086 | ||
a8449f23 AA |
1087 | /* avoid false positive for nodes_srcu, unlock happens in |
1088 | * dlm_midcomms_commit_mhandle which is a must call if success | |
1089 | */ | |
1090 | #ifndef __CHECKER__ | |
489d8e55 AA |
1091 | struct dlm_mhandle *dlm_midcomms_get_mhandle(int nodeid, int len, |
1092 | gfp_t allocation, char **ppc) | |
1093 | { | |
1094 | struct midcomms_node *node; | |
1095 | struct dlm_mhandle *mh; | |
1096 | struct dlm_msg *msg; | |
1097 | int idx; | |
1098 | ||
1099 | idx = srcu_read_lock(&nodes_srcu); | |
1100 | node = nodeid2node(nodeid, 0); | |
1101 | if (!node) { | |
1102 | WARN_ON_ONCE(1); | |
1103 | goto err; | |
1104 | } | |
1105 | ||
1106 | /* this is a bug, however we going on and hope it will be resolved */ | |
775af207 | 1107 | WARN_ON_ONCE(test_bit(DLM_NODE_FLAG_STOP_TX, &node->flags)); |
489d8e55 | 1108 | |
e1711fe3 | 1109 | mh = dlm_allocate_mhandle(allocation); |
489d8e55 AA |
1110 | if (!mh) |
1111 | goto err; | |
1112 | ||
6c547f26 AA |
1113 | mh->committed = false; |
1114 | mh->ack_rcv = NULL; | |
489d8e55 AA |
1115 | mh->idx = idx; |
1116 | mh->node = node; | |
1117 | ||
1118 | switch (node->version) { | |
1119 | case DLM_VERSION_3_1: | |
1120 | msg = dlm_lowcomms_new_msg(nodeid, len, allocation, ppc, | |
1121 | NULL, NULL); | |
1122 | if (!msg) { | |
6c547f26 | 1123 | dlm_free_mhandle(mh); |
489d8e55 AA |
1124 | goto err; |
1125 | } | |
1126 | ||
1127 | break; | |
1128 | case DLM_VERSION_3_2: | |
1129 | msg = dlm_midcomms_get_msg_3_2(mh, nodeid, len, allocation, | |
1130 | ppc); | |
1131 | if (!msg) { | |
6c547f26 | 1132 | dlm_free_mhandle(mh); |
489d8e55 AA |
1133 | goto err; |
1134 | } | |
1135 | ||
1136 | break; | |
1137 | default: | |
6c547f26 | 1138 | dlm_free_mhandle(mh); |
775af207 | 1139 | WARN_ON_ONCE(1); |
489d8e55 AA |
1140 | goto err; |
1141 | } | |
1142 | ||
1143 | mh->msg = msg; | |
1144 | ||
1145 | /* keep in mind that is a must to call | |
1146 | * dlm_midcomms_commit_msg() which releases | |
1147 | * nodes_srcu using mh->idx which is assumed | |
1148 | * here that the application will call it. | |
1149 | */ | |
1150 | return mh; | |
1151 | ||
1152 | err: | |
1153 | srcu_read_unlock(&nodes_srcu, idx); | |
1154 | return NULL; | |
1155 | } | |
a8449f23 | 1156 | #endif |
489d8e55 | 1157 | |
e01c4b7b AA |
1158 | static void dlm_midcomms_commit_msg_3_2_trace(const struct dlm_mhandle *mh, |
1159 | const void *name, int namelen) | |
1160 | { | |
1161 | switch (mh->inner_p->header.h_cmd) { | |
1162 | case DLM_MSG: | |
17827754 AA |
1163 | trace_dlm_send_message(mh->node->nodeid, mh->seq, |
1164 | &mh->inner_p->message, | |
e01c4b7b AA |
1165 | name, namelen); |
1166 | break; | |
1167 | case DLM_RCOM: | |
17827754 AA |
1168 | trace_dlm_send_rcom(mh->node->nodeid, mh->seq, |
1169 | &mh->inner_p->rcom); | |
e01c4b7b AA |
1170 | break; |
1171 | default: | |
1172 | /* nothing to trace */ | |
1173 | break; | |
1174 | } | |
1175 | } | |
1176 | ||
1177 | static void dlm_midcomms_commit_msg_3_2(struct dlm_mhandle *mh, | |
1178 | const void *name, int namelen) | |
489d8e55 AA |
1179 | { |
1180 | /* nexthdr chain for fast lookup */ | |
5b787667 | 1181 | mh->opts->o_nextcmd = mh->inner_p->header.h_cmd; |
489d8e55 | 1182 | mh->committed = true; |
e01c4b7b | 1183 | dlm_midcomms_commit_msg_3_2_trace(mh, name, namelen); |
489d8e55 AA |
1184 | dlm_lowcomms_commit_msg(mh->msg); |
1185 | } | |
1186 | ||
a8449f23 AA |
1187 | /* avoid false positive for nodes_srcu, lock was happen in |
1188 | * dlm_midcomms_get_mhandle | |
1189 | */ | |
1190 | #ifndef __CHECKER__ | |
e01c4b7b AA |
1191 | void dlm_midcomms_commit_mhandle(struct dlm_mhandle *mh, |
1192 | const void *name, int namelen) | |
489d8e55 | 1193 | { |
e01c4b7b | 1194 | |
489d8e55 AA |
1195 | switch (mh->node->version) { |
1196 | case DLM_VERSION_3_1: | |
1197 | srcu_read_unlock(&nodes_srcu, mh->idx); | |
1198 | ||
1199 | dlm_lowcomms_commit_msg(mh->msg); | |
1200 | dlm_lowcomms_put_msg(mh->msg); | |
1201 | /* mh is not part of rcu list in this case */ | |
6c547f26 | 1202 | dlm_free_mhandle(mh); |
489d8e55 AA |
1203 | break; |
1204 | case DLM_VERSION_3_2: | |
724b6bab AA |
1205 | /* held rcu read lock here, because we sending the |
1206 | * dlm message out, when we do that we could receive | |
1207 | * an ack back which releases the mhandle and we | |
1208 | * get a use after free. | |
1209 | */ | |
1210 | rcu_read_lock(); | |
e01c4b7b | 1211 | dlm_midcomms_commit_msg_3_2(mh, name, namelen); |
489d8e55 | 1212 | srcu_read_unlock(&nodes_srcu, mh->idx); |
724b6bab | 1213 | rcu_read_unlock(); |
489d8e55 AA |
1214 | break; |
1215 | default: | |
1216 | srcu_read_unlock(&nodes_srcu, mh->idx); | |
775af207 | 1217 | WARN_ON_ONCE(1); |
489d8e55 AA |
1218 | break; |
1219 | } | |
1220 | } | |
a8449f23 | 1221 | #endif |
489d8e55 AA |
1222 | |
1223 | int dlm_midcomms_start(void) | |
8b0188b0 AA |
1224 | { |
1225 | return dlm_lowcomms_start(); | |
1226 | } | |
1227 | ||
1228 | void dlm_midcomms_stop(void) | |
1229 | { | |
1230 | dlm_lowcomms_stop(); | |
1231 | } | |
1232 | ||
1233 | void dlm_midcomms_init(void) | |
489d8e55 AA |
1234 | { |
1235 | int i; | |
1236 | ||
1237 | for (i = 0; i < CONN_HASH_SIZE; i++) | |
1238 | INIT_HLIST_HEAD(&node_hash[i]); | |
1239 | ||
8b0188b0 AA |
1240 | dlm_lowcomms_init(); |
1241 | } | |
1242 | ||
1243 | void dlm_midcomms_exit(void) | |
1244 | { | |
1245 | dlm_lowcomms_exit(); | |
489d8e55 AA |
1246 | } |
1247 | ||
1248 | static void dlm_act_fin_ack_rcv(struct midcomms_node *node) | |
1249 | { | |
1250 | spin_lock(&node->state_lock); | |
1251 | pr_debug("receive active fin ack from node %d with state %s\n", | |
1252 | node->nodeid, dlm_state_str(node->state)); | |
1253 | ||
1254 | switch (node->state) { | |
1255 | case DLM_FIN_WAIT1: | |
1256 | node->state = DLM_FIN_WAIT2; | |
1257 | pr_debug("switch node %d to state %s\n", | |
1258 | node->nodeid, dlm_state_str(node->state)); | |
1259 | break; | |
1260 | case DLM_CLOSING: | |
1261 | midcomms_node_reset(node); | |
1262 | pr_debug("switch node %d to state %s\n", | |
1263 | node->nodeid, dlm_state_str(node->state)); | |
489d8e55 AA |
1264 | break; |
1265 | case DLM_CLOSED: | |
1266 | /* not valid but somehow we got what we want */ | |
1267 | wake_up(&node->shutdown_wait); | |
1268 | break; | |
1269 | default: | |
1270 | spin_unlock(&node->state_lock); | |
31864097 | 1271 | log_print("%s: unexpected state: %d", |
489d8e55 | 1272 | __func__, node->state); |
775af207 | 1273 | WARN_ON_ONCE(1); |
489d8e55 AA |
1274 | return; |
1275 | } | |
1276 | spin_unlock(&node->state_lock); | |
1277 | } | |
1278 | ||
1279 | void dlm_midcomms_add_member(int nodeid) | |
1280 | { | |
1281 | struct midcomms_node *node; | |
1282 | int idx; | |
1283 | ||
1284 | if (nodeid == dlm_our_nodeid()) | |
1285 | return; | |
1286 | ||
1287 | idx = srcu_read_lock(&nodes_srcu); | |
1288 | node = nodeid2node(nodeid, GFP_NOFS); | |
1289 | if (!node) { | |
1290 | srcu_read_unlock(&nodes_srcu, idx); | |
1291 | return; | |
1292 | } | |
1293 | ||
1294 | spin_lock(&node->state_lock); | |
1295 | if (!node->users) { | |
1296 | pr_debug("receive add member from node %d with state %s\n", | |
1297 | node->nodeid, dlm_state_str(node->state)); | |
1298 | switch (node->state) { | |
1299 | case DLM_ESTABLISHED: | |
1300 | break; | |
1301 | case DLM_CLOSED: | |
1302 | node->state = DLM_ESTABLISHED; | |
1303 | pr_debug("switch node %d to state %s\n", | |
1304 | node->nodeid, dlm_state_str(node->state)); | |
1305 | break; | |
1306 | default: | |
1307 | /* some invalid state passive shutdown | |
1308 | * was failed, we try to reset and | |
1309 | * hope it will go on. | |
1310 | */ | |
7d3848c0 | 1311 | log_print("reset node %d because shutdown stuck", |
489d8e55 AA |
1312 | node->nodeid); |
1313 | ||
1314 | midcomms_node_reset(node); | |
1315 | node->state = DLM_ESTABLISHED; | |
1316 | break; | |
1317 | } | |
1318 | } | |
1319 | ||
1320 | node->users++; | |
1aafd9c2 | 1321 | pr_debug("node %d users inc count %d\n", nodeid, node->users); |
489d8e55 AA |
1322 | spin_unlock(&node->state_lock); |
1323 | ||
1324 | srcu_read_unlock(&nodes_srcu, idx); | |
1325 | } | |
1326 | ||
1327 | void dlm_midcomms_remove_member(int nodeid) | |
1328 | { | |
1329 | struct midcomms_node *node; | |
1330 | int idx; | |
1331 | ||
1332 | if (nodeid == dlm_our_nodeid()) | |
1333 | return; | |
1334 | ||
1335 | idx = srcu_read_lock(&nodes_srcu); | |
1336 | node = nodeid2node(nodeid, 0); | |
1337 | if (!node) { | |
1338 | srcu_read_unlock(&nodes_srcu, idx); | |
1339 | return; | |
1340 | } | |
1341 | ||
1342 | spin_lock(&node->state_lock); | |
1343 | node->users--; | |
1aafd9c2 | 1344 | pr_debug("node %d users dec count %d\n", nodeid, node->users); |
489d8e55 AA |
1345 | |
1346 | /* hitting users count to zero means the | |
1347 | * other side is running dlm_midcomms_stop() | |
1348 | * we meet us to have a clean disconnect. | |
1349 | */ | |
1350 | if (node->users == 0) { | |
1351 | pr_debug("receive remove member from node %d with state %s\n", | |
1352 | node->nodeid, dlm_state_str(node->state)); | |
1353 | switch (node->state) { | |
1354 | case DLM_ESTABLISHED: | |
1355 | break; | |
1356 | case DLM_CLOSE_WAIT: | |
1357 | /* passive shutdown DLM_LAST_ACK case 2 */ | |
1358 | node->state = DLM_LAST_ACK; | |
489d8e55 AA |
1359 | pr_debug("switch node %d to state %s case 2\n", |
1360 | node->nodeid, dlm_state_str(node->state)); | |
a5849636 AA |
1361 | set_bit(DLM_NODE_FLAG_STOP_RX, &node->flags); |
1362 | dlm_send_fin(node, dlm_pas_fin_ack_rcv); | |
1363 | break; | |
489d8e55 AA |
1364 | case DLM_LAST_ACK: |
1365 | /* probably receive fin caught it, do nothing */ | |
1366 | break; | |
1367 | case DLM_CLOSED: | |
1368 | /* already gone, do nothing */ | |
1369 | break; | |
1370 | default: | |
31864097 | 1371 | log_print("%s: unexpected state: %d", |
489d8e55 AA |
1372 | __func__, node->state); |
1373 | break; | |
1374 | } | |
1375 | } | |
1376 | spin_unlock(&node->state_lock); | |
1377 | ||
1378 | srcu_read_unlock(&nodes_srcu, idx); | |
489d8e55 AA |
1379 | } |
1380 | ||
1381 | static void midcomms_node_release(struct rcu_head *rcu) | |
1382 | { | |
1383 | struct midcomms_node *node = container_of(rcu, struct midcomms_node, rcu); | |
1384 | ||
775af207 | 1385 | WARN_ON_ONCE(atomic_read(&node->send_queue_cnt)); |
7354fa4e | 1386 | dlm_send_queue_flush(node); |
489d8e55 AA |
1387 | kfree(node); |
1388 | } | |
1389 | ||
b8b750e0 AA |
1390 | void dlm_midcomms_version_wait(void) |
1391 | { | |
1392 | struct midcomms_node *node; | |
1393 | int i, idx, ret; | |
1394 | ||
1395 | idx = srcu_read_lock(&nodes_srcu); | |
1396 | for (i = 0; i < CONN_HASH_SIZE; i++) { | |
1397 | hlist_for_each_entry_rcu(node, &node_hash[i], hlist) { | |
1398 | ret = wait_event_timeout(node->shutdown_wait, | |
1399 | node->version != DLM_VERSION_NOT_SET || | |
1400 | node->state == DLM_CLOSED || | |
1401 | test_bit(DLM_NODE_FLAG_CLOSE, &node->flags), | |
1402 | DLM_SHUTDOWN_TIMEOUT); | |
1403 | if (!ret || test_bit(DLM_NODE_FLAG_CLOSE, &node->flags)) | |
1404 | pr_debug("version wait timed out for node %d with state %s\n", | |
1405 | node->nodeid, dlm_state_str(node->state)); | |
1406 | } | |
1407 | } | |
1408 | srcu_read_unlock(&nodes_srcu, idx); | |
1409 | } | |
1410 | ||
489d8e55 AA |
1411 | static void midcomms_shutdown(struct midcomms_node *node) |
1412 | { | |
1413 | int ret; | |
1414 | ||
1415 | /* old protocol, we don't wait for pending operations */ | |
1416 | switch (node->version) { | |
1417 | case DLM_VERSION_3_2: | |
1418 | break; | |
1419 | default: | |
1420 | return; | |
1421 | } | |
1422 | ||
1423 | spin_lock(&node->state_lock); | |
1424 | pr_debug("receive active shutdown for node %d with state %s\n", | |
1425 | node->nodeid, dlm_state_str(node->state)); | |
1426 | switch (node->state) { | |
1427 | case DLM_ESTABLISHED: | |
1428 | node->state = DLM_FIN_WAIT1; | |
1429 | pr_debug("switch node %d to state %s case 2\n", | |
1430 | node->nodeid, dlm_state_str(node->state)); | |
a5849636 | 1431 | dlm_send_fin(node, dlm_act_fin_ack_rcv); |
489d8e55 AA |
1432 | break; |
1433 | case DLM_CLOSED: | |
1434 | /* we have what we want */ | |
54fbe0c1 | 1435 | break; |
489d8e55 AA |
1436 | default: |
1437 | /* busy to enter DLM_FIN_WAIT1, wait until passive | |
1438 | * done in shutdown_wait to enter DLM_CLOSED. | |
1439 | */ | |
1440 | break; | |
1441 | } | |
1442 | spin_unlock(&node->state_lock); | |
1443 | ||
a5849636 AA |
1444 | if (DLM_DEBUG_FENCE_TERMINATION) |
1445 | msleep(5000); | |
489d8e55 AA |
1446 | |
1447 | /* wait for other side dlm + fin */ | |
1448 | ret = wait_event_timeout(node->shutdown_wait, | |
1449 | node->state == DLM_CLOSED || | |
1450 | test_bit(DLM_NODE_FLAG_CLOSE, &node->flags), | |
1451 | DLM_SHUTDOWN_TIMEOUT); | |
54fbe0c1 | 1452 | if (!ret || test_bit(DLM_NODE_FLAG_CLOSE, &node->flags)) |
489d8e55 AA |
1453 | pr_debug("active shutdown timed out for node %d with state %s\n", |
1454 | node->nodeid, dlm_state_str(node->state)); | |
54fbe0c1 AA |
1455 | else |
1456 | pr_debug("active shutdown done for node %d with state %s\n", | |
1457 | node->nodeid, dlm_state_str(node->state)); | |
489d8e55 AA |
1458 | } |
1459 | ||
1460 | void dlm_midcomms_shutdown(void) | |
1461 | { | |
1462 | struct midcomms_node *node; | |
1463 | int i, idx; | |
1464 | ||
1465 | mutex_lock(&close_lock); | |
1466 | idx = srcu_read_lock(&nodes_srcu); | |
1467 | for (i = 0; i < CONN_HASH_SIZE; i++) { | |
1468 | hlist_for_each_entry_rcu(node, &node_hash[i], hlist) { | |
1469 | midcomms_shutdown(node); | |
1470 | ||
5b2f981f AA |
1471 | dlm_delete_debug_comms_file(node->debugfs); |
1472 | ||
489d8e55 AA |
1473 | spin_lock(&nodes_lock); |
1474 | hlist_del_rcu(&node->hlist); | |
1475 | spin_unlock(&nodes_lock); | |
1476 | ||
1477 | call_srcu(&nodes_srcu, &node->rcu, midcomms_node_release); | |
1478 | } | |
1479 | } | |
1480 | srcu_read_unlock(&nodes_srcu, idx); | |
1481 | mutex_unlock(&close_lock); | |
54fbe0c1 AA |
1482 | |
1483 | dlm_lowcomms_shutdown(); | |
489d8e55 AA |
1484 | } |
1485 | ||
1486 | int dlm_midcomms_close(int nodeid) | |
1487 | { | |
1488 | struct midcomms_node *node; | |
1489 | int idx, ret; | |
1490 | ||
1491 | if (nodeid == dlm_our_nodeid()) | |
1492 | return 0; | |
1493 | ||
2c3fa6ae AA |
1494 | dlm_stop_lockspaces_check(); |
1495 | ||
489d8e55 AA |
1496 | idx = srcu_read_lock(&nodes_srcu); |
1497 | /* Abort pending close/remove operation */ | |
1498 | node = nodeid2node(nodeid, 0); | |
1499 | if (node) { | |
1500 | /* let shutdown waiters leave */ | |
1501 | set_bit(DLM_NODE_FLAG_CLOSE, &node->flags); | |
1502 | wake_up(&node->shutdown_wait); | |
1503 | } | |
1504 | srcu_read_unlock(&nodes_srcu, idx); | |
1505 | ||
1506 | synchronize_srcu(&nodes_srcu); | |
1507 | ||
1508 | idx = srcu_read_lock(&nodes_srcu); | |
1509 | mutex_lock(&close_lock); | |
1510 | node = nodeid2node(nodeid, 0); | |
1511 | if (!node) { | |
1512 | mutex_unlock(&close_lock); | |
1513 | srcu_read_unlock(&nodes_srcu, idx); | |
1514 | return dlm_lowcomms_close(nodeid); | |
1515 | } | |
1516 | ||
1517 | ret = dlm_lowcomms_close(nodeid); | |
1518 | spin_lock(&node->state_lock); | |
1519 | midcomms_node_reset(node); | |
1520 | spin_unlock(&node->state_lock); | |
1521 | srcu_read_unlock(&nodes_srcu, idx); | |
1522 | mutex_unlock(&close_lock); | |
1523 | ||
1524 | return ret; | |
1525 | } | |
9af5b8f0 AA |
1526 | |
1527 | /* debug functionality to send raw dlm msg from user space */ | |
1528 | struct dlm_rawmsg_data { | |
1529 | struct midcomms_node *node; | |
1530 | void *buf; | |
1531 | }; | |
1532 | ||
1533 | static void midcomms_new_rawmsg_cb(void *data) | |
1534 | { | |
1535 | struct dlm_rawmsg_data *rd = data; | |
1536 | struct dlm_header *h = rd->buf; | |
1537 | ||
1538 | switch (h->h_version) { | |
1539 | case cpu_to_le32(DLM_VERSION_3_1): | |
1540 | break; | |
1541 | default: | |
1542 | switch (h->h_cmd) { | |
1543 | case DLM_OPTS: | |
1544 | if (!h->u.h_seq) | |
3428785a | 1545 | h->u.h_seq = cpu_to_le32(rd->node->seq_send++); |
9af5b8f0 AA |
1546 | break; |
1547 | default: | |
1548 | break; | |
1549 | } | |
1550 | break; | |
1551 | } | |
1552 | } | |
1553 | ||
1554 | int dlm_midcomms_rawmsg_send(struct midcomms_node *node, void *buf, | |
1555 | int buflen) | |
1556 | { | |
1557 | struct dlm_rawmsg_data rd; | |
1558 | struct dlm_msg *msg; | |
1559 | char *msgbuf; | |
1560 | ||
1561 | rd.node = node; | |
1562 | rd.buf = buf; | |
1563 | ||
1564 | msg = dlm_lowcomms_new_msg(node->nodeid, buflen, GFP_NOFS, | |
1565 | &msgbuf, midcomms_new_rawmsg_cb, &rd); | |
1566 | if (!msg) | |
1567 | return -ENOMEM; | |
1568 | ||
1569 | memcpy(msgbuf, buf, buflen); | |
1570 | dlm_lowcomms_commit_msg(msg); | |
1571 | return 0; | |
1572 | } | |
1573 |