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8adf0536 JB |
1 | /* -*- mode: c; c-basic-offset: 8; -*- |
2 | * vim: noexpandtab sw=8 ts=8 sts=0: | |
3 | * | |
4 | * stack_user.c | |
5 | * | |
6 | * Code which interfaces ocfs2 with fs/dlm and a userspace stack. | |
7 | * | |
8 | * Copyright (C) 2007 Oracle. All rights reserved. | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or | |
11 | * modify it under the terms of the GNU General Public | |
12 | * License as published by the Free Software Foundation, version 2. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
17 | * General Public License for more details. | |
18 | */ | |
19 | ||
20 | #include <linux/module.h> | |
6427a727 JB |
21 | #include <linux/fs.h> |
22 | #include <linux/miscdevice.h> | |
23 | #include <linux/mutex.h> | |
24 | #include <linux/reboot.h> | |
462c7e6a | 25 | #include <asm/uaccess.h> |
8adf0536 | 26 | |
cf4d8d75 | 27 | #include "ocfs2.h" /* For struct ocfs2_lock_res */ |
8adf0536 JB |
28 | #include "stackglue.h" |
29 | ||
30 | ||
6427a727 JB |
31 | /* |
32 | * The control protocol starts with a handshake. Until the handshake | |
33 | * is complete, the control device will fail all write(2)s. | |
34 | * | |
35 | * The handshake is simple. First, the client reads until EOF. Each line | |
36 | * of output is a supported protocol tag. All protocol tags are a single | |
37 | * character followed by a two hex digit version number. Currently the | |
38 | * only things supported is T01, for "Text-base version 0x01". Next, the | |
de870ef0 JB |
39 | * client writes the version they would like to use, including the newline. |
40 | * Thus, the protocol tag is 'T01\n'. If the version tag written is | |
41 | * unknown, -EINVAL is returned. Once the negotiation is complete, the | |
42 | * client can start sending messages. | |
43 | * | |
d4b95eef | 44 | * The T01 protocol has three messages. First is the "SETN" message. |
3cfd4ab6 JB |
45 | * It has the following syntax: |
46 | * | |
47 | * SETN<space><8-char-hex-nodenum><newline> | |
48 | * | |
49 | * This is 14 characters. | |
50 | * | |
51 | * The "SETN" message must be the first message following the protocol. | |
52 | * It tells ocfs2_control the local node number. | |
53 | * | |
d4b95eef JB |
54 | * Next comes the "SETV" message. It has the following syntax: |
55 | * | |
56 | * SETV<space><2-char-hex-major><space><2-char-hex-minor><newline> | |
57 | * | |
58 | * This is 11 characters. | |
59 | * | |
60 | * The "SETV" message sets the filesystem locking protocol version as | |
61 | * negotiated by the client. The client negotiates based on the maximum | |
62 | * version advertised in /sys/fs/ocfs2/max_locking_protocol. The major | |
63 | * number from the "SETV" message must match | |
64 | * user_stack.sp_proto->lp_max_version.pv_major, and the minor number | |
65 | * must be less than or equal to ...->lp_max_version.pv_minor. | |
66 | * | |
67 | * Once this information has been set, mounts will be allowed. From this | |
68 | * point on, the "DOWN" message can be sent for node down notification. | |
69 | * It has the following syntax: | |
de870ef0 JB |
70 | * |
71 | * DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline> | |
72 | * | |
73 | * eg: | |
74 | * | |
75 | * DOWN 632A924FDD844190BDA93C0DF6B94899 00000001\n | |
76 | * | |
77 | * This is 47 characters. | |
6427a727 JB |
78 | */ |
79 | ||
462c7e6a JB |
80 | /* |
81 | * Whether or not the client has done the handshake. | |
82 | * For now, we have just one protocol version. | |
83 | */ | |
84 | #define OCFS2_CONTROL_PROTO "T01\n" | |
85 | #define OCFS2_CONTROL_PROTO_LEN 4 | |
3cfd4ab6 JB |
86 | |
87 | /* Handshake states */ | |
462c7e6a JB |
88 | #define OCFS2_CONTROL_HANDSHAKE_INVALID (0) |
89 | #define OCFS2_CONTROL_HANDSHAKE_READ (1) | |
3cfd4ab6 JB |
90 | #define OCFS2_CONTROL_HANDSHAKE_PROTOCOL (2) |
91 | #define OCFS2_CONTROL_HANDSHAKE_VALID (3) | |
92 | ||
93 | /* Messages */ | |
94 | #define OCFS2_CONTROL_MESSAGE_OP_LEN 4 | |
95 | #define OCFS2_CONTROL_MESSAGE_SETNODE_OP "SETN" | |
96 | #define OCFS2_CONTROL_MESSAGE_SETNODE_TOTAL_LEN 14 | |
d4b95eef JB |
97 | #define OCFS2_CONTROL_MESSAGE_SETVERSION_OP "SETV" |
98 | #define OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN 11 | |
3cfd4ab6 | 99 | #define OCFS2_CONTROL_MESSAGE_DOWN_OP "DOWN" |
de870ef0 JB |
100 | #define OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN 47 |
101 | #define OCFS2_TEXT_UUID_LEN 32 | |
d4b95eef | 102 | #define OCFS2_CONTROL_MESSAGE_VERNUM_LEN 2 |
de870ef0 | 103 | #define OCFS2_CONTROL_MESSAGE_NODENUM_LEN 8 |
462c7e6a | 104 | |
6427a727 JB |
105 | /* |
106 | * ocfs2_live_connection is refcounted because the filesystem and | |
107 | * miscdevice sides can detach in different order. Let's just be safe. | |
108 | */ | |
109 | struct ocfs2_live_connection { | |
110 | struct list_head oc_list; | |
111 | struct ocfs2_cluster_connection *oc_conn; | |
112 | }; | |
113 | ||
462c7e6a JB |
114 | struct ocfs2_control_private { |
115 | struct list_head op_list; | |
116 | int op_state; | |
3cfd4ab6 | 117 | int op_this_node; |
d4b95eef | 118 | struct ocfs2_protocol_version op_proto; |
3cfd4ab6 JB |
119 | }; |
120 | ||
121 | /* SETN<space><8-char-hex-nodenum><newline> */ | |
122 | struct ocfs2_control_message_setn { | |
123 | char tag[OCFS2_CONTROL_MESSAGE_OP_LEN]; | |
124 | char space; | |
125 | char nodestr[OCFS2_CONTROL_MESSAGE_NODENUM_LEN]; | |
126 | char newline; | |
127 | }; | |
128 | ||
d4b95eef JB |
129 | /* SETV<space><2-char-hex-major><space><2-char-hex-minor><newline> */ |
130 | struct ocfs2_control_message_setv { | |
131 | char tag[OCFS2_CONTROL_MESSAGE_OP_LEN]; | |
132 | char space1; | |
133 | char major[OCFS2_CONTROL_MESSAGE_VERNUM_LEN]; | |
134 | char space2; | |
135 | char minor[OCFS2_CONTROL_MESSAGE_VERNUM_LEN]; | |
136 | char newline; | |
137 | }; | |
138 | ||
3cfd4ab6 JB |
139 | /* DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline> */ |
140 | struct ocfs2_control_message_down { | |
141 | char tag[OCFS2_CONTROL_MESSAGE_OP_LEN]; | |
142 | char space1; | |
143 | char uuid[OCFS2_TEXT_UUID_LEN]; | |
144 | char space2; | |
145 | char nodestr[OCFS2_CONTROL_MESSAGE_NODENUM_LEN]; | |
146 | char newline; | |
147 | }; | |
148 | ||
149 | union ocfs2_control_message { | |
150 | char tag[OCFS2_CONTROL_MESSAGE_OP_LEN]; | |
151 | struct ocfs2_control_message_setn u_setn; | |
d4b95eef | 152 | struct ocfs2_control_message_setv u_setv; |
3cfd4ab6 | 153 | struct ocfs2_control_message_down u_down; |
462c7e6a JB |
154 | }; |
155 | ||
cf4d8d75 DT |
156 | static struct ocfs2_stack_plugin user_stack; |
157 | ||
6427a727 | 158 | static atomic_t ocfs2_control_opened; |
3cfd4ab6 | 159 | static int ocfs2_control_this_node = -1; |
d4b95eef | 160 | static struct ocfs2_protocol_version running_proto; |
6427a727 JB |
161 | |
162 | static LIST_HEAD(ocfs2_live_connection_list); | |
462c7e6a | 163 | static LIST_HEAD(ocfs2_control_private_list); |
6427a727 JB |
164 | static DEFINE_MUTEX(ocfs2_control_lock); |
165 | ||
462c7e6a JB |
166 | static inline void ocfs2_control_set_handshake_state(struct file *file, |
167 | int state) | |
168 | { | |
169 | struct ocfs2_control_private *p = file->private_data; | |
170 | p->op_state = state; | |
171 | } | |
172 | ||
173 | static inline int ocfs2_control_get_handshake_state(struct file *file) | |
174 | { | |
175 | struct ocfs2_control_private *p = file->private_data; | |
176 | return p->op_state; | |
177 | } | |
178 | ||
6427a727 JB |
179 | static struct ocfs2_live_connection *ocfs2_connection_find(const char *name) |
180 | { | |
181 | size_t len = strlen(name); | |
182 | struct ocfs2_live_connection *c; | |
183 | ||
184 | BUG_ON(!mutex_is_locked(&ocfs2_control_lock)); | |
185 | ||
186 | list_for_each_entry(c, &ocfs2_live_connection_list, oc_list) { | |
187 | if ((c->oc_conn->cc_namelen == len) && | |
188 | !strncmp(c->oc_conn->cc_name, name, len)) | |
189 | return c; | |
190 | } | |
191 | ||
192 | return c; | |
193 | } | |
194 | ||
195 | /* | |
196 | * ocfs2_live_connection structures are created underneath the ocfs2 | |
197 | * mount path. Since the VFS prevents multiple calls to | |
198 | * fill_super(), we can't get dupes here. | |
199 | */ | |
200 | static int ocfs2_live_connection_new(struct ocfs2_cluster_connection *conn, | |
201 | struct ocfs2_live_connection **c_ret) | |
202 | { | |
203 | int rc = 0; | |
204 | struct ocfs2_live_connection *c; | |
205 | ||
206 | c = kzalloc(sizeof(struct ocfs2_live_connection), GFP_KERNEL); | |
207 | if (!c) | |
208 | return -ENOMEM; | |
209 | ||
210 | mutex_lock(&ocfs2_control_lock); | |
211 | c->oc_conn = conn; | |
212 | ||
213 | if (atomic_read(&ocfs2_control_opened)) | |
214 | list_add(&c->oc_list, &ocfs2_live_connection_list); | |
215 | else { | |
216 | printk(KERN_ERR | |
217 | "ocfs2: Userspace control daemon is not present\n"); | |
218 | rc = -ESRCH; | |
219 | } | |
220 | ||
221 | mutex_unlock(&ocfs2_control_lock); | |
222 | ||
223 | if (!rc) | |
224 | *c_ret = c; | |
225 | else | |
226 | kfree(c); | |
227 | ||
228 | return rc; | |
229 | } | |
230 | ||
231 | /* | |
232 | * This function disconnects the cluster connection from ocfs2_control. | |
233 | * Afterwards, userspace can't affect the cluster connection. | |
234 | */ | |
235 | static void ocfs2_live_connection_drop(struct ocfs2_live_connection *c) | |
236 | { | |
237 | mutex_lock(&ocfs2_control_lock); | |
238 | list_del_init(&c->oc_list); | |
239 | c->oc_conn = NULL; | |
240 | mutex_unlock(&ocfs2_control_lock); | |
241 | ||
242 | kfree(c); | |
243 | } | |
244 | ||
3cfd4ab6 JB |
245 | static int ocfs2_control_cfu(void *target, size_t target_len, |
246 | const char __user *buf, size_t count) | |
462c7e6a JB |
247 | { |
248 | /* The T01 expects write(2) calls to have exactly one command */ | |
3cfd4ab6 JB |
249 | if ((count != target_len) || |
250 | (count > sizeof(union ocfs2_control_message))) | |
462c7e6a JB |
251 | return -EINVAL; |
252 | ||
253 | if (copy_from_user(target, buf, target_len)) | |
254 | return -EFAULT; | |
255 | ||
3cfd4ab6 | 256 | return 0; |
462c7e6a JB |
257 | } |
258 | ||
3cfd4ab6 JB |
259 | static ssize_t ocfs2_control_validate_protocol(struct file *file, |
260 | const char __user *buf, | |
261 | size_t count) | |
462c7e6a JB |
262 | { |
263 | ssize_t ret; | |
264 | char kbuf[OCFS2_CONTROL_PROTO_LEN]; | |
265 | ||
266 | ret = ocfs2_control_cfu(kbuf, OCFS2_CONTROL_PROTO_LEN, | |
267 | buf, count); | |
3cfd4ab6 | 268 | if (ret) |
462c7e6a JB |
269 | return ret; |
270 | ||
271 | if (strncmp(kbuf, OCFS2_CONTROL_PROTO, OCFS2_CONTROL_PROTO_LEN)) | |
272 | return -EINVAL; | |
273 | ||
462c7e6a | 274 | ocfs2_control_set_handshake_state(file, |
3cfd4ab6 | 275 | OCFS2_CONTROL_HANDSHAKE_PROTOCOL); |
462c7e6a JB |
276 | |
277 | return count; | |
278 | } | |
279 | ||
de870ef0 JB |
280 | static void ocfs2_control_send_down(const char *uuid, |
281 | int nodenum) | |
282 | { | |
283 | struct ocfs2_live_connection *c; | |
284 | ||
285 | mutex_lock(&ocfs2_control_lock); | |
286 | ||
287 | c = ocfs2_connection_find(uuid); | |
288 | if (c) { | |
289 | BUG_ON(c->oc_conn == NULL); | |
290 | c->oc_conn->cc_recovery_handler(nodenum, | |
291 | c->oc_conn->cc_recovery_data); | |
292 | } | |
293 | ||
294 | mutex_unlock(&ocfs2_control_lock); | |
295 | } | |
296 | ||
3cfd4ab6 JB |
297 | /* |
298 | * Called whenever configuration elements are sent to /dev/ocfs2_control. | |
299 | * If all configuration elements are present, try to set the global | |
d4b95eef JB |
300 | * values. If there is a problem, return an error. Skip any missing |
301 | * elements, and only bump ocfs2_control_opened when we have all elements | |
302 | * and are successful. | |
3cfd4ab6 JB |
303 | */ |
304 | static int ocfs2_control_install_private(struct file *file) | |
305 | { | |
306 | int rc = 0; | |
307 | int set_p = 1; | |
308 | struct ocfs2_control_private *p = file->private_data; | |
de870ef0 | 309 | |
3cfd4ab6 JB |
310 | BUG_ON(p->op_state != OCFS2_CONTROL_HANDSHAKE_PROTOCOL); |
311 | ||
d4b95eef JB |
312 | mutex_lock(&ocfs2_control_lock); |
313 | ||
314 | if (p->op_this_node < 0) { | |
3cfd4ab6 | 315 | set_p = 0; |
d4b95eef JB |
316 | } else if ((ocfs2_control_this_node >= 0) && |
317 | (ocfs2_control_this_node != p->op_this_node)) { | |
318 | rc = -EINVAL; | |
319 | goto out_unlock; | |
320 | } | |
3cfd4ab6 | 321 | |
d4b95eef JB |
322 | if (!p->op_proto.pv_major) { |
323 | set_p = 0; | |
324 | } else if (!list_empty(&ocfs2_live_connection_list) && | |
325 | ((running_proto.pv_major != p->op_proto.pv_major) || | |
326 | (running_proto.pv_minor != p->op_proto.pv_minor))) { | |
3cfd4ab6 | 327 | rc = -EINVAL; |
d4b95eef JB |
328 | goto out_unlock; |
329 | } | |
330 | ||
331 | if (set_p) { | |
332 | ocfs2_control_this_node = p->op_this_node; | |
333 | running_proto.pv_major = p->op_proto.pv_major; | |
334 | running_proto.pv_minor = p->op_proto.pv_minor; | |
335 | } | |
336 | ||
337 | out_unlock: | |
3cfd4ab6 JB |
338 | mutex_unlock(&ocfs2_control_lock); |
339 | ||
340 | if (!rc && set_p) { | |
341 | /* We set the global values successfully */ | |
342 | atomic_inc(&ocfs2_control_opened); | |
343 | ocfs2_control_set_handshake_state(file, | |
344 | OCFS2_CONTROL_HANDSHAKE_VALID); | |
345 | } | |
346 | ||
347 | return rc; | |
348 | } | |
349 | ||
cf4d8d75 DT |
350 | static int ocfs2_control_get_this_node(void) |
351 | { | |
352 | int rc; | |
353 | ||
354 | mutex_lock(&ocfs2_control_lock); | |
355 | if (ocfs2_control_this_node < 0) | |
356 | rc = -EINVAL; | |
357 | else | |
358 | rc = ocfs2_control_this_node; | |
359 | mutex_unlock(&ocfs2_control_lock); | |
360 | ||
361 | return rc; | |
362 | } | |
363 | ||
3cfd4ab6 JB |
364 | static int ocfs2_control_do_setnode_msg(struct file *file, |
365 | struct ocfs2_control_message_setn *msg) | |
de870ef0 | 366 | { |
de870ef0 | 367 | long nodenum; |
3cfd4ab6 JB |
368 | char *ptr = NULL; |
369 | struct ocfs2_control_private *p = file->private_data; | |
de870ef0 | 370 | |
3cfd4ab6 JB |
371 | if (ocfs2_control_get_handshake_state(file) != |
372 | OCFS2_CONTROL_HANDSHAKE_PROTOCOL) | |
373 | return -EINVAL; | |
de870ef0 | 374 | |
3cfd4ab6 JB |
375 | if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_SETNODE_OP, |
376 | OCFS2_CONTROL_MESSAGE_OP_LEN)) | |
377 | return -EINVAL; | |
378 | ||
379 | if ((msg->space != ' ') || (msg->newline != '\n')) | |
380 | return -EINVAL; | |
381 | msg->space = msg->newline = '\0'; | |
382 | ||
383 | nodenum = simple_strtol(msg->nodestr, &ptr, 16); | |
384 | if (!ptr || *ptr) | |
385 | return -EINVAL; | |
386 | ||
387 | if ((nodenum == LONG_MIN) || (nodenum == LONG_MAX) || | |
388 | (nodenum > INT_MAX) || (nodenum < 0)) | |
389 | return -ERANGE; | |
390 | p->op_this_node = nodenum; | |
391 | ||
392 | return ocfs2_control_install_private(file); | |
393 | } | |
394 | ||
d4b95eef JB |
395 | static int ocfs2_control_do_setversion_msg(struct file *file, |
396 | struct ocfs2_control_message_setv *msg) | |
397 | { | |
398 | long major, minor; | |
399 | char *ptr = NULL; | |
400 | struct ocfs2_control_private *p = file->private_data; | |
401 | struct ocfs2_protocol_version *max = | |
402 | &user_stack.sp_proto->lp_max_version; | |
403 | ||
404 | if (ocfs2_control_get_handshake_state(file) != | |
405 | OCFS2_CONTROL_HANDSHAKE_PROTOCOL) | |
406 | return -EINVAL; | |
407 | ||
408 | if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP, | |
409 | OCFS2_CONTROL_MESSAGE_OP_LEN)) | |
410 | return -EINVAL; | |
411 | ||
412 | if ((msg->space1 != ' ') || (msg->space2 != ' ') || | |
413 | (msg->newline != '\n')) | |
414 | return -EINVAL; | |
415 | msg->space1 = msg->space2 = msg->newline = '\0'; | |
416 | ||
417 | major = simple_strtol(msg->major, &ptr, 16); | |
418 | if (!ptr || *ptr) | |
419 | return -EINVAL; | |
420 | minor = simple_strtol(msg->minor, &ptr, 16); | |
421 | if (!ptr || *ptr) | |
422 | return -EINVAL; | |
423 | ||
424 | /* | |
425 | * The major must be between 1 and 255, inclusive. The minor | |
426 | * must be between 0 and 255, inclusive. The version passed in | |
427 | * must be within the maximum version supported by the filesystem. | |
428 | */ | |
429 | if ((major == LONG_MIN) || (major == LONG_MAX) || | |
430 | (major > (u8)-1) || (major < 1)) | |
431 | return -ERANGE; | |
432 | if ((minor == LONG_MIN) || (minor == LONG_MAX) || | |
433 | (minor > (u8)-1) || (minor < 0)) | |
434 | return -ERANGE; | |
435 | if ((major != max->pv_major) || | |
436 | (minor > max->pv_minor)) | |
437 | return -EINVAL; | |
438 | ||
439 | p->op_proto.pv_major = major; | |
440 | p->op_proto.pv_minor = minor; | |
441 | ||
442 | return ocfs2_control_install_private(file); | |
443 | } | |
444 | ||
3cfd4ab6 JB |
445 | static int ocfs2_control_do_down_msg(struct file *file, |
446 | struct ocfs2_control_message_down *msg) | |
447 | { | |
448 | long nodenum; | |
449 | char *p = NULL; | |
450 | ||
451 | if (ocfs2_control_get_handshake_state(file) != | |
452 | OCFS2_CONTROL_HANDSHAKE_VALID) | |
453 | return -EINVAL; | |
de870ef0 | 454 | |
3cfd4ab6 JB |
455 | if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_DOWN_OP, |
456 | OCFS2_CONTROL_MESSAGE_OP_LEN)) | |
de870ef0 JB |
457 | return -EINVAL; |
458 | ||
3cfd4ab6 JB |
459 | if ((msg->space1 != ' ') || (msg->space2 != ' ') || |
460 | (msg->newline != '\n')) | |
de870ef0 | 461 | return -EINVAL; |
3cfd4ab6 | 462 | msg->space1 = msg->space2 = msg->newline = '\0'; |
de870ef0 | 463 | |
3cfd4ab6 | 464 | nodenum = simple_strtol(msg->nodestr, &p, 16); |
de870ef0 JB |
465 | if (!p || *p) |
466 | return -EINVAL; | |
467 | ||
468 | if ((nodenum == LONG_MIN) || (nodenum == LONG_MAX) || | |
469 | (nodenum > INT_MAX) || (nodenum < 0)) | |
470 | return -ERANGE; | |
471 | ||
3cfd4ab6 | 472 | ocfs2_control_send_down(msg->uuid, nodenum); |
de870ef0 | 473 | |
3cfd4ab6 JB |
474 | return 0; |
475 | } | |
476 | ||
477 | static ssize_t ocfs2_control_message(struct file *file, | |
478 | const char __user *buf, | |
479 | size_t count) | |
480 | { | |
481 | ssize_t ret; | |
482 | union ocfs2_control_message msg; | |
483 | ||
484 | /* Try to catch padding issues */ | |
485 | WARN_ON(offsetof(struct ocfs2_control_message_down, uuid) != | |
486 | (sizeof(msg.u_down.tag) + sizeof(msg.u_down.space1))); | |
487 | ||
488 | memset(&msg, 0, sizeof(union ocfs2_control_message)); | |
489 | ret = ocfs2_control_cfu(&msg, count, buf, count); | |
490 | if (ret) | |
491 | goto out; | |
492 | ||
493 | if ((count == OCFS2_CONTROL_MESSAGE_SETNODE_TOTAL_LEN) && | |
494 | !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETNODE_OP, | |
495 | OCFS2_CONTROL_MESSAGE_OP_LEN)) | |
496 | ret = ocfs2_control_do_setnode_msg(file, &msg.u_setn); | |
d4b95eef JB |
497 | else if ((count == OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN) && |
498 | !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP, | |
499 | OCFS2_CONTROL_MESSAGE_OP_LEN)) | |
500 | ret = ocfs2_control_do_setversion_msg(file, &msg.u_setv); | |
3cfd4ab6 JB |
501 | else if ((count == OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN) && |
502 | !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_DOWN_OP, | |
503 | OCFS2_CONTROL_MESSAGE_OP_LEN)) | |
504 | ret = ocfs2_control_do_down_msg(file, &msg.u_down); | |
505 | else | |
506 | ret = -EINVAL; | |
507 | ||
508 | out: | |
509 | return ret ? ret : count; | |
de870ef0 | 510 | } |
6427a727 JB |
511 | |
512 | static ssize_t ocfs2_control_write(struct file *file, | |
513 | const char __user *buf, | |
514 | size_t count, | |
515 | loff_t *ppos) | |
8adf0536 | 516 | { |
462c7e6a JB |
517 | ssize_t ret; |
518 | ||
519 | switch (ocfs2_control_get_handshake_state(file)) { | |
520 | case OCFS2_CONTROL_HANDSHAKE_INVALID: | |
521 | ret = -EINVAL; | |
522 | break; | |
523 | ||
524 | case OCFS2_CONTROL_HANDSHAKE_READ: | |
3cfd4ab6 JB |
525 | ret = ocfs2_control_validate_protocol(file, buf, |
526 | count); | |
462c7e6a JB |
527 | break; |
528 | ||
3cfd4ab6 | 529 | case OCFS2_CONTROL_HANDSHAKE_PROTOCOL: |
462c7e6a | 530 | case OCFS2_CONTROL_HANDSHAKE_VALID: |
de870ef0 | 531 | ret = ocfs2_control_message(file, buf, count); |
462c7e6a JB |
532 | break; |
533 | ||
534 | default: | |
535 | BUG(); | |
536 | ret = -EIO; | |
537 | break; | |
538 | } | |
539 | ||
540 | return ret; | |
8adf0536 JB |
541 | } |
542 | ||
462c7e6a JB |
543 | /* |
544 | * This is a naive version. If we ever have a new protocol, we'll expand | |
545 | * it. Probably using seq_file. | |
546 | */ | |
6427a727 JB |
547 | static ssize_t ocfs2_control_read(struct file *file, |
548 | char __user *buf, | |
549 | size_t count, | |
550 | loff_t *ppos) | |
551 | { | |
462c7e6a JB |
552 | char *proto_string = OCFS2_CONTROL_PROTO; |
553 | size_t to_write = 0; | |
554 | ||
555 | if (*ppos >= OCFS2_CONTROL_PROTO_LEN) | |
556 | return 0; | |
557 | ||
558 | to_write = OCFS2_CONTROL_PROTO_LEN - *ppos; | |
559 | if (to_write > count) | |
560 | to_write = count; | |
561 | if (copy_to_user(buf, proto_string + *ppos, to_write)) | |
562 | return -EFAULT; | |
563 | ||
564 | *ppos += to_write; | |
565 | ||
566 | /* Have we read the whole protocol list? */ | |
567 | if (*ppos >= OCFS2_CONTROL_PROTO_LEN) | |
568 | ocfs2_control_set_handshake_state(file, | |
569 | OCFS2_CONTROL_HANDSHAKE_READ); | |
570 | ||
571 | return to_write; | |
6427a727 JB |
572 | } |
573 | ||
574 | static int ocfs2_control_release(struct inode *inode, struct file *file) | |
575 | { | |
462c7e6a JB |
576 | struct ocfs2_control_private *p = file->private_data; |
577 | ||
578 | mutex_lock(&ocfs2_control_lock); | |
579 | ||
580 | if (ocfs2_control_get_handshake_state(file) != | |
581 | OCFS2_CONTROL_HANDSHAKE_VALID) | |
582 | goto out; | |
583 | ||
6427a727 | 584 | if (atomic_dec_and_test(&ocfs2_control_opened)) { |
6427a727 JB |
585 | if (!list_empty(&ocfs2_live_connection_list)) { |
586 | /* XXX: Do bad things! */ | |
587 | printk(KERN_ERR | |
588 | "ocfs2: Unexpected release of ocfs2_control!\n" | |
589 | " Loss of cluster connection requires " | |
590 | "an emergency restart!\n"); | |
591 | emergency_restart(); | |
592 | } | |
d4b95eef JB |
593 | /* |
594 | * Last valid close clears the node number and resets | |
595 | * the locking protocol version | |
596 | */ | |
3cfd4ab6 | 597 | ocfs2_control_this_node = -1; |
d4b95eef JB |
598 | running_proto.pv_major = 0; |
599 | running_proto.pv_major = 0; | |
6427a727 JB |
600 | } |
601 | ||
462c7e6a JB |
602 | out: |
603 | list_del_init(&p->op_list); | |
604 | file->private_data = NULL; | |
605 | ||
606 | mutex_unlock(&ocfs2_control_lock); | |
607 | ||
608 | kfree(p); | |
609 | ||
6427a727 JB |
610 | return 0; |
611 | } | |
612 | ||
613 | static int ocfs2_control_open(struct inode *inode, struct file *file) | |
614 | { | |
462c7e6a JB |
615 | struct ocfs2_control_private *p; |
616 | ||
617 | p = kzalloc(sizeof(struct ocfs2_control_private), GFP_KERNEL); | |
618 | if (!p) | |
619 | return -ENOMEM; | |
3cfd4ab6 | 620 | p->op_this_node = -1; |
462c7e6a JB |
621 | |
622 | mutex_lock(&ocfs2_control_lock); | |
623 | file->private_data = p; | |
624 | list_add(&p->op_list, &ocfs2_control_private_list); | |
625 | mutex_unlock(&ocfs2_control_lock); | |
6427a727 JB |
626 | |
627 | return 0; | |
628 | } | |
629 | ||
630 | static const struct file_operations ocfs2_control_fops = { | |
631 | .open = ocfs2_control_open, | |
632 | .release = ocfs2_control_release, | |
633 | .read = ocfs2_control_read, | |
634 | .write = ocfs2_control_write, | |
635 | .owner = THIS_MODULE, | |
636 | }; | |
637 | ||
638 | struct miscdevice ocfs2_control_device = { | |
639 | .minor = MISC_DYNAMIC_MINOR, | |
640 | .name = "ocfs2_control", | |
641 | .fops = &ocfs2_control_fops, | |
642 | }; | |
643 | ||
644 | static int ocfs2_control_init(void) | |
645 | { | |
646 | int rc; | |
647 | ||
648 | atomic_set(&ocfs2_control_opened, 0); | |
649 | ||
650 | rc = misc_register(&ocfs2_control_device); | |
651 | if (rc) | |
652 | printk(KERN_ERR | |
653 | "ocfs2: Unable to register ocfs2_control device " | |
654 | "(errno %d)\n", | |
655 | -rc); | |
656 | ||
657 | return rc; | |
658 | } | |
659 | ||
660 | static void ocfs2_control_exit(void) | |
661 | { | |
662 | int rc; | |
663 | ||
664 | rc = misc_deregister(&ocfs2_control_device); | |
665 | if (rc) | |
666 | printk(KERN_ERR | |
667 | "ocfs2: Unable to deregister ocfs2_control device " | |
668 | "(errno %d)\n", | |
669 | -rc); | |
670 | } | |
671 | ||
cf4d8d75 DT |
672 | static struct dlm_lksb *fsdlm_astarg_to_lksb(void *astarg) |
673 | { | |
674 | struct ocfs2_lock_res *res = astarg; | |
675 | return &res->l_lksb.lksb_fsdlm; | |
676 | } | |
677 | ||
678 | static void fsdlm_lock_ast_wrapper(void *astarg) | |
679 | { | |
680 | struct dlm_lksb *lksb = fsdlm_astarg_to_lksb(astarg); | |
681 | int status = lksb->sb_status; | |
682 | ||
683 | BUG_ON(user_stack.sp_proto == NULL); | |
684 | ||
685 | /* | |
686 | * For now we're punting on the issue of other non-standard errors | |
687 | * where we can't tell if the unlock_ast or lock_ast should be called. | |
688 | * The main "other error" that's possible is EINVAL which means the | |
689 | * function was called with invalid args, which shouldn't be possible | |
690 | * since the caller here is under our control. Other non-standard | |
691 | * errors probably fall into the same category, or otherwise are fatal | |
692 | * which means we can't carry on anyway. | |
693 | */ | |
694 | ||
695 | if (status == -DLM_EUNLOCK || status == -DLM_ECANCEL) | |
696 | user_stack.sp_proto->lp_unlock_ast(astarg, 0); | |
697 | else | |
698 | user_stack.sp_proto->lp_lock_ast(astarg); | |
699 | } | |
700 | ||
701 | static void fsdlm_blocking_ast_wrapper(void *astarg, int level) | |
702 | { | |
703 | BUG_ON(user_stack.sp_proto == NULL); | |
704 | ||
705 | user_stack.sp_proto->lp_blocking_ast(astarg, level); | |
706 | } | |
707 | ||
708 | static int user_dlm_lock(struct ocfs2_cluster_connection *conn, | |
709 | int mode, | |
710 | union ocfs2_dlm_lksb *lksb, | |
711 | u32 flags, | |
712 | void *name, | |
713 | unsigned int namelen, | |
714 | void *astarg) | |
715 | { | |
716 | int ret; | |
717 | ||
718 | if (!lksb->lksb_fsdlm.sb_lvbptr) | |
719 | lksb->lksb_fsdlm.sb_lvbptr = (char *)lksb + | |
720 | sizeof(struct dlm_lksb); | |
721 | ||
722 | ret = dlm_lock(conn->cc_lockspace, mode, &lksb->lksb_fsdlm, | |
723 | flags|DLM_LKF_NODLCKWT, name, namelen, 0, | |
724 | fsdlm_lock_ast_wrapper, astarg, | |
725 | fsdlm_blocking_ast_wrapper); | |
726 | return ret; | |
727 | } | |
728 | ||
729 | static int user_dlm_unlock(struct ocfs2_cluster_connection *conn, | |
730 | union ocfs2_dlm_lksb *lksb, | |
731 | u32 flags, | |
732 | void *astarg) | |
733 | { | |
734 | int ret; | |
735 | ||
736 | ret = dlm_unlock(conn->cc_lockspace, lksb->lksb_fsdlm.sb_lkid, | |
737 | flags, &lksb->lksb_fsdlm, astarg); | |
738 | return ret; | |
739 | } | |
740 | ||
741 | static int user_dlm_lock_status(union ocfs2_dlm_lksb *lksb) | |
742 | { | |
743 | return lksb->lksb_fsdlm.sb_status; | |
744 | } | |
745 | ||
746 | static void *user_dlm_lvb(union ocfs2_dlm_lksb *lksb) | |
747 | { | |
748 | return (void *)(lksb->lksb_fsdlm.sb_lvbptr); | |
749 | } | |
750 | ||
751 | static void user_dlm_dump_lksb(union ocfs2_dlm_lksb *lksb) | |
752 | { | |
753 | } | |
754 | ||
755 | /* | |
756 | * Compare a requested locking protocol version against the current one. | |
757 | * | |
758 | * If the major numbers are different, they are incompatible. | |
759 | * If the current minor is greater than the request, they are incompatible. | |
760 | * If the current minor is less than or equal to the request, they are | |
761 | * compatible, and the requester should run at the current minor version. | |
762 | */ | |
763 | static int fs_protocol_compare(struct ocfs2_protocol_version *existing, | |
764 | struct ocfs2_protocol_version *request) | |
765 | { | |
766 | if (existing->pv_major != request->pv_major) | |
767 | return 1; | |
768 | ||
769 | if (existing->pv_minor > request->pv_minor) | |
770 | return 1; | |
771 | ||
772 | if (existing->pv_minor < request->pv_minor) | |
773 | request->pv_minor = existing->pv_minor; | |
774 | ||
775 | return 0; | |
776 | } | |
777 | ||
778 | static int user_cluster_connect(struct ocfs2_cluster_connection *conn) | |
779 | { | |
780 | dlm_lockspace_t *fsdlm; | |
781 | struct ocfs2_live_connection *control; | |
782 | int rc = 0; | |
783 | ||
784 | BUG_ON(conn == NULL); | |
785 | ||
786 | rc = ocfs2_live_connection_new(conn, &control); | |
787 | if (rc) | |
788 | goto out; | |
789 | ||
790 | /* | |
791 | * running_proto must have been set before we allowed any mounts | |
792 | * to proceed. | |
793 | */ | |
794 | if (fs_protocol_compare(&running_proto, &conn->cc_version)) { | |
795 | printk(KERN_ERR | |
796 | "Unable to mount with fs locking protocol version " | |
797 | "%u.%u because the userspace control daemon has " | |
798 | "negotiated %u.%u\n", | |
799 | conn->cc_version.pv_major, conn->cc_version.pv_minor, | |
800 | running_proto.pv_major, running_proto.pv_minor); | |
801 | rc = -EPROTO; | |
802 | ocfs2_live_connection_drop(control); | |
803 | goto out; | |
804 | } | |
805 | ||
806 | rc = dlm_new_lockspace(conn->cc_name, strlen(conn->cc_name), | |
807 | &fsdlm, DLM_LSFL_FS, DLM_LVB_LEN); | |
808 | if (rc) { | |
809 | ocfs2_live_connection_drop(control); | |
810 | goto out; | |
811 | } | |
812 | ||
813 | conn->cc_private = control; | |
814 | conn->cc_lockspace = fsdlm; | |
815 | out: | |
816 | return rc; | |
817 | } | |
818 | ||
819 | static int user_cluster_disconnect(struct ocfs2_cluster_connection *conn, | |
820 | int hangup_pending) | |
821 | { | |
822 | dlm_release_lockspace(conn->cc_lockspace, 2); | |
823 | conn->cc_lockspace = NULL; | |
824 | ocfs2_live_connection_drop(conn->cc_private); | |
825 | conn->cc_private = NULL; | |
826 | return 0; | |
827 | } | |
828 | ||
829 | static int user_cluster_this_node(unsigned int *this_node) | |
830 | { | |
831 | int rc; | |
832 | ||
833 | rc = ocfs2_control_get_this_node(); | |
834 | if (rc < 0) | |
835 | return rc; | |
836 | ||
837 | *this_node = rc; | |
838 | return 0; | |
839 | } | |
840 | ||
841 | static struct ocfs2_stack_operations user_stack_ops = { | |
842 | .connect = user_cluster_connect, | |
843 | .disconnect = user_cluster_disconnect, | |
844 | .this_node = user_cluster_this_node, | |
845 | .dlm_lock = user_dlm_lock, | |
846 | .dlm_unlock = user_dlm_unlock, | |
847 | .lock_status = user_dlm_lock_status, | |
848 | .lock_lvb = user_dlm_lvb, | |
849 | .dump_lksb = user_dlm_dump_lksb, | |
850 | }; | |
851 | ||
852 | static struct ocfs2_stack_plugin user_stack = { | |
853 | .sp_name = "user", | |
854 | .sp_ops = &user_stack_ops, | |
855 | .sp_owner = THIS_MODULE, | |
856 | }; | |
857 | ||
858 | ||
6427a727 JB |
859 | static int __init user_stack_init(void) |
860 | { | |
cf4d8d75 DT |
861 | int rc; |
862 | ||
863 | rc = ocfs2_control_init(); | |
864 | if (!rc) { | |
865 | rc = ocfs2_stack_glue_register(&user_stack); | |
866 | if (rc) | |
867 | ocfs2_control_exit(); | |
868 | } | |
869 | ||
870 | return rc; | |
6427a727 JB |
871 | } |
872 | ||
8adf0536 JB |
873 | static void __exit user_stack_exit(void) |
874 | { | |
cf4d8d75 | 875 | ocfs2_stack_glue_unregister(&user_stack); |
6427a727 | 876 | ocfs2_control_exit(); |
8adf0536 JB |
877 | } |
878 | ||
879 | MODULE_AUTHOR("Oracle"); | |
880 | MODULE_DESCRIPTION("ocfs2 driver for userspace cluster stacks"); | |
881 | MODULE_LICENSE("GPL"); | |
882 | module_init(user_stack_init); | |
883 | module_exit(user_stack_exit); |