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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>
21#include <linux/fs.h>
22#include <linux/miscdevice.h>
23#include <linux/mutex.h>
24#include <linux/slab.h>
25#include <linux/reboot.h>
26#include <linux/sched.h>
27#include <asm/uaccess.h>
28
29#include "stackglue.h"
30
31#include <linux/dlm_plock.h>
32
33/*
34 * The control protocol starts with a handshake. Until the handshake
35 * is complete, the control device will fail all write(2)s.
36 *
37 * The handshake is simple. First, the client reads until EOF. Each line
38 * of output is a supported protocol tag. All protocol tags are a single
39 * character followed by a two hex digit version number. Currently the
40 * only things supported is T01, for "Text-base version 0x01". Next, the
41 * client writes the version they would like to use, including the newline.
42 * Thus, the protocol tag is 'T01\n'. If the version tag written is
43 * unknown, -EINVAL is returned. Once the negotiation is complete, the
44 * client can start sending messages.
45 *
46 * The T01 protocol has three messages. First is the "SETN" message.
47 * It has the following syntax:
48 *
49 * SETN<space><8-char-hex-nodenum><newline>
50 *
51 * This is 14 characters.
52 *
53 * The "SETN" message must be the first message following the protocol.
54 * It tells ocfs2_control the local node number.
55 *
56 * Next comes the "SETV" message. It has the following syntax:
57 *
58 * SETV<space><2-char-hex-major><space><2-char-hex-minor><newline>
59 *
60 * This is 11 characters.
61 *
62 * The "SETV" message sets the filesystem locking protocol version as
63 * negotiated by the client. The client negotiates based on the maximum
64 * version advertised in /sys/fs/ocfs2/max_locking_protocol. The major
65 * number from the "SETV" message must match
66 * ocfs2_user_plugin.sp_max_proto.pv_major, and the minor number
67 * must be less than or equal to ...sp_max_version.pv_minor.
68 *
69 * Once this information has been set, mounts will be allowed. From this
70 * point on, the "DOWN" message can be sent for node down notification.
71 * It has the following syntax:
72 *
73 * DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline>
74 *
75 * eg:
76 *
77 * DOWN 632A924FDD844190BDA93C0DF6B94899 00000001\n
78 *
79 * This is 47 characters.
80 */
81
82/*
83 * Whether or not the client has done the handshake.
84 * For now, we have just one protocol version.
85 */
86#define OCFS2_CONTROL_PROTO "T01\n"
87#define OCFS2_CONTROL_PROTO_LEN 4
88
89/* Handshake states */
90#define OCFS2_CONTROL_HANDSHAKE_INVALID (0)
91#define OCFS2_CONTROL_HANDSHAKE_READ (1)
92#define OCFS2_CONTROL_HANDSHAKE_PROTOCOL (2)
93#define OCFS2_CONTROL_HANDSHAKE_VALID (3)
94
95/* Messages */
96#define OCFS2_CONTROL_MESSAGE_OP_LEN 4
97#define OCFS2_CONTROL_MESSAGE_SETNODE_OP "SETN"
98#define OCFS2_CONTROL_MESSAGE_SETNODE_TOTAL_LEN 14
99#define OCFS2_CONTROL_MESSAGE_SETVERSION_OP "SETV"
100#define OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN 11
101#define OCFS2_CONTROL_MESSAGE_DOWN_OP "DOWN"
102#define OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN 47
103#define OCFS2_TEXT_UUID_LEN 32
104#define OCFS2_CONTROL_MESSAGE_VERNUM_LEN 2
105#define OCFS2_CONTROL_MESSAGE_NODENUM_LEN 8
106#define VERSION_LOCK "version_lock"
107
108enum ocfs2_connection_type {
109 WITH_CONTROLD,
110 NO_CONTROLD
111};
112
113/*
114 * ocfs2_live_connection is refcounted because the filesystem and
115 * miscdevice sides can detach in different order. Let's just be safe.
116 */
117struct ocfs2_live_connection {
118 struct list_head oc_list;
119 struct ocfs2_cluster_connection *oc_conn;
120 enum ocfs2_connection_type oc_type;
121 atomic_t oc_this_node;
122 int oc_our_slot;
123 struct dlm_lksb oc_version_lksb;
124 char oc_lvb[DLM_LVB_LEN];
125 struct completion oc_sync_wait;
126 wait_queue_head_t oc_wait;
127};
128
129struct ocfs2_control_private {
130 struct list_head op_list;
131 int op_state;
132 int op_this_node;
133 struct ocfs2_protocol_version op_proto;
134};
135
136/* SETN<space><8-char-hex-nodenum><newline> */
137struct ocfs2_control_message_setn {
138 char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
139 char space;
140 char nodestr[OCFS2_CONTROL_MESSAGE_NODENUM_LEN];
141 char newline;
142};
143
144/* SETV<space><2-char-hex-major><space><2-char-hex-minor><newline> */
145struct ocfs2_control_message_setv {
146 char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
147 char space1;
148 char major[OCFS2_CONTROL_MESSAGE_VERNUM_LEN];
149 char space2;
150 char minor[OCFS2_CONTROL_MESSAGE_VERNUM_LEN];
151 char newline;
152};
153
154/* DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline> */
155struct ocfs2_control_message_down {
156 char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
157 char space1;
158 char uuid[OCFS2_TEXT_UUID_LEN];
159 char space2;
160 char nodestr[OCFS2_CONTROL_MESSAGE_NODENUM_LEN];
161 char newline;
162};
163
164union ocfs2_control_message {
165 char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
166 struct ocfs2_control_message_setn u_setn;
167 struct ocfs2_control_message_setv u_setv;
168 struct ocfs2_control_message_down u_down;
169};
170
171static struct ocfs2_stack_plugin ocfs2_user_plugin;
172
173static atomic_t ocfs2_control_opened;
174static int ocfs2_control_this_node = -1;
175static struct ocfs2_protocol_version running_proto;
176
177static LIST_HEAD(ocfs2_live_connection_list);
178static LIST_HEAD(ocfs2_control_private_list);
179static DEFINE_MUTEX(ocfs2_control_lock);
180
181static inline void ocfs2_control_set_handshake_state(struct file *file,
182 int state)
183{
184 struct ocfs2_control_private *p = file->private_data;
185 p->op_state = state;
186}
187
188static inline int ocfs2_control_get_handshake_state(struct file *file)
189{
190 struct ocfs2_control_private *p = file->private_data;
191 return p->op_state;
192}
193
194static struct ocfs2_live_connection *ocfs2_connection_find(const char *name)
195{
196 size_t len = strlen(name);
197 struct ocfs2_live_connection *c;
198
199 BUG_ON(!mutex_is_locked(&ocfs2_control_lock));
200
201 list_for_each_entry(c, &ocfs2_live_connection_list, oc_list) {
202 if ((c->oc_conn->cc_namelen == len) &&
203 !strncmp(c->oc_conn->cc_name, name, len))
204 return c;
205 }
206
207 return NULL;
208}
209
210/*
211 * ocfs2_live_connection structures are created underneath the ocfs2
212 * mount path. Since the VFS prevents multiple calls to
213 * fill_super(), we can't get dupes here.
214 */
215static int ocfs2_live_connection_attach(struct ocfs2_cluster_connection *conn,
216 struct ocfs2_live_connection *c)
217{
218 int rc = 0;
219
220 mutex_lock(&ocfs2_control_lock);
221 c->oc_conn = conn;
222
223 if ((c->oc_type == NO_CONTROLD) || atomic_read(&ocfs2_control_opened))
224 list_add(&c->oc_list, &ocfs2_live_connection_list);
225 else {
226 printk(KERN_ERR
227 "ocfs2: Userspace control daemon is not present\n");
228 rc = -ESRCH;
229 }
230
231 mutex_unlock(&ocfs2_control_lock);
232 return rc;
233}
234
235/*
236 * This function disconnects the cluster connection from ocfs2_control.
237 * Afterwards, userspace can't affect the cluster connection.
238 */
239static void ocfs2_live_connection_drop(struct ocfs2_live_connection *c)
240{
241 mutex_lock(&ocfs2_control_lock);
242 list_del_init(&c->oc_list);
243 c->oc_conn = NULL;
244 mutex_unlock(&ocfs2_control_lock);
245
246 kfree(c);
247}
248
249static int ocfs2_control_cfu(void *target, size_t target_len,
250 const char __user *buf, size_t count)
251{
252 /* The T01 expects write(2) calls to have exactly one command */
253 if ((count != target_len) ||
254 (count > sizeof(union ocfs2_control_message)))
255 return -EINVAL;
256
257 if (copy_from_user(target, buf, target_len))
258 return -EFAULT;
259
260 return 0;
261}
262
263static ssize_t ocfs2_control_validate_protocol(struct file *file,
264 const char __user *buf,
265 size_t count)
266{
267 ssize_t ret;
268 char kbuf[OCFS2_CONTROL_PROTO_LEN];
269
270 ret = ocfs2_control_cfu(kbuf, OCFS2_CONTROL_PROTO_LEN,
271 buf, count);
272 if (ret)
273 return ret;
274
275 if (strncmp(kbuf, OCFS2_CONTROL_PROTO, OCFS2_CONTROL_PROTO_LEN))
276 return -EINVAL;
277
278 ocfs2_control_set_handshake_state(file,
279 OCFS2_CONTROL_HANDSHAKE_PROTOCOL);
280
281 return count;
282}
283
284static void ocfs2_control_send_down(const char *uuid,
285 int nodenum)
286{
287 struct ocfs2_live_connection *c;
288
289 mutex_lock(&ocfs2_control_lock);
290
291 c = ocfs2_connection_find(uuid);
292 if (c) {
293 BUG_ON(c->oc_conn == NULL);
294 c->oc_conn->cc_recovery_handler(nodenum,
295 c->oc_conn->cc_recovery_data);
296 }
297
298 mutex_unlock(&ocfs2_control_lock);
299}
300
301/*
302 * Called whenever configuration elements are sent to /dev/ocfs2_control.
303 * If all configuration elements are present, try to set the global
304 * values. If there is a problem, return an error. Skip any missing
305 * elements, and only bump ocfs2_control_opened when we have all elements
306 * and are successful.
307 */
308static int ocfs2_control_install_private(struct file *file)
309{
310 int rc = 0;
311 int set_p = 1;
312 struct ocfs2_control_private *p = file->private_data;
313
314 BUG_ON(p->op_state != OCFS2_CONTROL_HANDSHAKE_PROTOCOL);
315
316 mutex_lock(&ocfs2_control_lock);
317
318 if (p->op_this_node < 0) {
319 set_p = 0;
320 } else if ((ocfs2_control_this_node >= 0) &&
321 (ocfs2_control_this_node != p->op_this_node)) {
322 rc = -EINVAL;
323 goto out_unlock;
324 }
325
326 if (!p->op_proto.pv_major) {
327 set_p = 0;
328 } else if (!list_empty(&ocfs2_live_connection_list) &&
329 ((running_proto.pv_major != p->op_proto.pv_major) ||
330 (running_proto.pv_minor != p->op_proto.pv_minor))) {
331 rc = -EINVAL;
332 goto out_unlock;
333 }
334
335 if (set_p) {
336 ocfs2_control_this_node = p->op_this_node;
337 running_proto.pv_major = p->op_proto.pv_major;
338 running_proto.pv_minor = p->op_proto.pv_minor;
339 }
340
341out_unlock:
342 mutex_unlock(&ocfs2_control_lock);
343
344 if (!rc && set_p) {
345 /* We set the global values successfully */
346 atomic_inc(&ocfs2_control_opened);
347 ocfs2_control_set_handshake_state(file,
348 OCFS2_CONTROL_HANDSHAKE_VALID);
349 }
350
351 return rc;
352}
353
354static int ocfs2_control_get_this_node(void)
355{
356 int rc;
357
358 mutex_lock(&ocfs2_control_lock);
359 if (ocfs2_control_this_node < 0)
360 rc = -EINVAL;
361 else
362 rc = ocfs2_control_this_node;
363 mutex_unlock(&ocfs2_control_lock);
364
365 return rc;
366}
367
368static int ocfs2_control_do_setnode_msg(struct file *file,
369 struct ocfs2_control_message_setn *msg)
370{
371 long nodenum;
372 char *ptr = NULL;
373 struct ocfs2_control_private *p = file->private_data;
374
375 if (ocfs2_control_get_handshake_state(file) !=
376 OCFS2_CONTROL_HANDSHAKE_PROTOCOL)
377 return -EINVAL;
378
379 if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_SETNODE_OP,
380 OCFS2_CONTROL_MESSAGE_OP_LEN))
381 return -EINVAL;
382
383 if ((msg->space != ' ') || (msg->newline != '\n'))
384 return -EINVAL;
385 msg->space = msg->newline = '\0';
386
387 nodenum = simple_strtol(msg->nodestr, &ptr, 16);
388 if (!ptr || *ptr)
389 return -EINVAL;
390
391 if ((nodenum == LONG_MIN) || (nodenum == LONG_MAX) ||
392 (nodenum > INT_MAX) || (nodenum < 0))
393 return -ERANGE;
394 p->op_this_node = nodenum;
395
396 return ocfs2_control_install_private(file);
397}
398
399static int ocfs2_control_do_setversion_msg(struct file *file,
400 struct ocfs2_control_message_setv *msg)
401 {
402 long major, minor;
403 char *ptr = NULL;
404 struct ocfs2_control_private *p = file->private_data;
405 struct ocfs2_protocol_version *max =
406 &ocfs2_user_plugin.sp_max_proto;
407
408 if (ocfs2_control_get_handshake_state(file) !=
409 OCFS2_CONTROL_HANDSHAKE_PROTOCOL)
410 return -EINVAL;
411
412 if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP,
413 OCFS2_CONTROL_MESSAGE_OP_LEN))
414 return -EINVAL;
415
416 if ((msg->space1 != ' ') || (msg->space2 != ' ') ||
417 (msg->newline != '\n'))
418 return -EINVAL;
419 msg->space1 = msg->space2 = msg->newline = '\0';
420
421 major = simple_strtol(msg->major, &ptr, 16);
422 if (!ptr || *ptr)
423 return -EINVAL;
424 minor = simple_strtol(msg->minor, &ptr, 16);
425 if (!ptr || *ptr)
426 return -EINVAL;
427
428 /*
429 * The major must be between 1 and 255, inclusive. The minor
430 * must be between 0 and 255, inclusive. The version passed in
431 * must be within the maximum version supported by the filesystem.
432 */
433 if ((major == LONG_MIN) || (major == LONG_MAX) ||
434 (major > (u8)-1) || (major < 1))
435 return -ERANGE;
436 if ((minor == LONG_MIN) || (minor == LONG_MAX) ||
437 (minor > (u8)-1) || (minor < 0))
438 return -ERANGE;
439 if ((major != max->pv_major) ||
440 (minor > max->pv_minor))
441 return -EINVAL;
442
443 p->op_proto.pv_major = major;
444 p->op_proto.pv_minor = minor;
445
446 return ocfs2_control_install_private(file);
447}
448
449static int ocfs2_control_do_down_msg(struct file *file,
450 struct ocfs2_control_message_down *msg)
451{
452 long nodenum;
453 char *p = NULL;
454
455 if (ocfs2_control_get_handshake_state(file) !=
456 OCFS2_CONTROL_HANDSHAKE_VALID)
457 return -EINVAL;
458
459 if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_DOWN_OP,
460 OCFS2_CONTROL_MESSAGE_OP_LEN))
461 return -EINVAL;
462
463 if ((msg->space1 != ' ') || (msg->space2 != ' ') ||
464 (msg->newline != '\n'))
465 return -EINVAL;
466 msg->space1 = msg->space2 = msg->newline = '\0';
467
468 nodenum = simple_strtol(msg->nodestr, &p, 16);
469 if (!p || *p)
470 return -EINVAL;
471
472 if ((nodenum == LONG_MIN) || (nodenum == LONG_MAX) ||
473 (nodenum > INT_MAX) || (nodenum < 0))
474 return -ERANGE;
475
476 ocfs2_control_send_down(msg->uuid, nodenum);
477
478 return 0;
479}
480
481static ssize_t ocfs2_control_message(struct file *file,
482 const char __user *buf,
483 size_t count)
484{
485 ssize_t ret;
486 union ocfs2_control_message msg;
487
488 /* Try to catch padding issues */
489 WARN_ON(offsetof(struct ocfs2_control_message_down, uuid) !=
490 (sizeof(msg.u_down.tag) + sizeof(msg.u_down.space1)));
491
492 memset(&msg, 0, sizeof(union ocfs2_control_message));
493 ret = ocfs2_control_cfu(&msg, count, buf, count);
494 if (ret)
495 goto out;
496
497 if ((count == OCFS2_CONTROL_MESSAGE_SETNODE_TOTAL_LEN) &&
498 !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETNODE_OP,
499 OCFS2_CONTROL_MESSAGE_OP_LEN))
500 ret = ocfs2_control_do_setnode_msg(file, &msg.u_setn);
501 else if ((count == OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN) &&
502 !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP,
503 OCFS2_CONTROL_MESSAGE_OP_LEN))
504 ret = ocfs2_control_do_setversion_msg(file, &msg.u_setv);
505 else if ((count == OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN) &&
506 !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_DOWN_OP,
507 OCFS2_CONTROL_MESSAGE_OP_LEN))
508 ret = ocfs2_control_do_down_msg(file, &msg.u_down);
509 else
510 ret = -EINVAL;
511
512out:
513 return ret ? ret : count;
514}
515
516static ssize_t ocfs2_control_write(struct file *file,
517 const char __user *buf,
518 size_t count,
519 loff_t *ppos)
520{
521 ssize_t ret;
522
523 switch (ocfs2_control_get_handshake_state(file)) {
524 case OCFS2_CONTROL_HANDSHAKE_INVALID:
525 ret = -EINVAL;
526 break;
527
528 case OCFS2_CONTROL_HANDSHAKE_READ:
529 ret = ocfs2_control_validate_protocol(file, buf,
530 count);
531 break;
532
533 case OCFS2_CONTROL_HANDSHAKE_PROTOCOL:
534 case OCFS2_CONTROL_HANDSHAKE_VALID:
535 ret = ocfs2_control_message(file, buf, count);
536 break;
537
538 default:
539 BUG();
540 ret = -EIO;
541 break;
542 }
543
544 return ret;
545}
546
547/*
548 * This is a naive version. If we ever have a new protocol, we'll expand
549 * it. Probably using seq_file.
550 */
551static ssize_t ocfs2_control_read(struct file *file,
552 char __user *buf,
553 size_t count,
554 loff_t *ppos)
555{
556 ssize_t ret;
557
558 ret = simple_read_from_buffer(buf, count, ppos,
559 OCFS2_CONTROL_PROTO, OCFS2_CONTROL_PROTO_LEN);
560
561 /* Have we read the whole protocol list? */
562 if (ret > 0 && *ppos >= OCFS2_CONTROL_PROTO_LEN)
563 ocfs2_control_set_handshake_state(file,
564 OCFS2_CONTROL_HANDSHAKE_READ);
565
566 return ret;
567}
568
569static int ocfs2_control_release(struct inode *inode, struct file *file)
570{
571 struct ocfs2_control_private *p = file->private_data;
572
573 mutex_lock(&ocfs2_control_lock);
574
575 if (ocfs2_control_get_handshake_state(file) !=
576 OCFS2_CONTROL_HANDSHAKE_VALID)
577 goto out;
578
579 if (atomic_dec_and_test(&ocfs2_control_opened)) {
580 if (!list_empty(&ocfs2_live_connection_list)) {
581 /* XXX: Do bad things! */
582 printk(KERN_ERR
583 "ocfs2: Unexpected release of ocfs2_control!\n"
584 " Loss of cluster connection requires "
585 "an emergency restart!\n");
586 emergency_restart();
587 }
588 /*
589 * Last valid close clears the node number and resets
590 * the locking protocol version
591 */
592 ocfs2_control_this_node = -1;
593 running_proto.pv_major = 0;
594 running_proto.pv_major = 0;
595 }
596
597out:
598 list_del_init(&p->op_list);
599 file->private_data = NULL;
600
601 mutex_unlock(&ocfs2_control_lock);
602
603 kfree(p);
604
605 return 0;
606}
607
608static int ocfs2_control_open(struct inode *inode, struct file *file)
609{
610 struct ocfs2_control_private *p;
611
612 p = kzalloc(sizeof(struct ocfs2_control_private), GFP_KERNEL);
613 if (!p)
614 return -ENOMEM;
615 p->op_this_node = -1;
616
617 mutex_lock(&ocfs2_control_lock);
618 file->private_data = p;
619 list_add(&p->op_list, &ocfs2_control_private_list);
620 mutex_unlock(&ocfs2_control_lock);
621
622 return 0;
623}
624
625static const struct file_operations ocfs2_control_fops = {
626 .open = ocfs2_control_open,
627 .release = ocfs2_control_release,
628 .read = ocfs2_control_read,
629 .write = ocfs2_control_write,
630 .owner = THIS_MODULE,
631 .llseek = default_llseek,
632};
633
634static struct miscdevice ocfs2_control_device = {
635 .minor = MISC_DYNAMIC_MINOR,
636 .name = "ocfs2_control",
637 .fops = &ocfs2_control_fops,
638};
639
640static int ocfs2_control_init(void)
641{
642 int rc;
643
644 atomic_set(&ocfs2_control_opened, 0);
645
646 rc = misc_register(&ocfs2_control_device);
647 if (rc)
648 printk(KERN_ERR
649 "ocfs2: Unable to register ocfs2_control device "
650 "(errno %d)\n",
651 -rc);
652
653 return rc;
654}
655
656static void ocfs2_control_exit(void)
657{
658 int rc;
659
660 rc = misc_deregister(&ocfs2_control_device);
661 if (rc)
662 printk(KERN_ERR
663 "ocfs2: Unable to deregister ocfs2_control device "
664 "(errno %d)\n",
665 -rc);
666}
667
668static void fsdlm_lock_ast_wrapper(void *astarg)
669{
670 struct ocfs2_dlm_lksb *lksb = astarg;
671 int status = lksb->lksb_fsdlm.sb_status;
672
673 /*
674 * For now we're punting on the issue of other non-standard errors
675 * where we can't tell if the unlock_ast or lock_ast should be called.
676 * The main "other error" that's possible is EINVAL which means the
677 * function was called with invalid args, which shouldn't be possible
678 * since the caller here is under our control. Other non-standard
679 * errors probably fall into the same category, or otherwise are fatal
680 * which means we can't carry on anyway.
681 */
682
683 if (status == -DLM_EUNLOCK || status == -DLM_ECANCEL)
684 lksb->lksb_conn->cc_proto->lp_unlock_ast(lksb, 0);
685 else
686 lksb->lksb_conn->cc_proto->lp_lock_ast(lksb);
687}
688
689static void fsdlm_blocking_ast_wrapper(void *astarg, int level)
690{
691 struct ocfs2_dlm_lksb *lksb = astarg;
692
693 lksb->lksb_conn->cc_proto->lp_blocking_ast(lksb, level);
694}
695
696static int user_dlm_lock(struct ocfs2_cluster_connection *conn,
697 int mode,
698 struct ocfs2_dlm_lksb *lksb,
699 u32 flags,
700 void *name,
701 unsigned int namelen)
702{
703 int ret;
704
705 if (!lksb->lksb_fsdlm.sb_lvbptr)
706 lksb->lksb_fsdlm.sb_lvbptr = (char *)lksb +
707 sizeof(struct dlm_lksb);
708
709 ret = dlm_lock(conn->cc_lockspace, mode, &lksb->lksb_fsdlm,
710 flags|DLM_LKF_NODLCKWT, name, namelen, 0,
711 fsdlm_lock_ast_wrapper, lksb,
712 fsdlm_blocking_ast_wrapper);
713 return ret;
714}
715
716static int user_dlm_unlock(struct ocfs2_cluster_connection *conn,
717 struct ocfs2_dlm_lksb *lksb,
718 u32 flags)
719{
720 int ret;
721
722 ret = dlm_unlock(conn->cc_lockspace, lksb->lksb_fsdlm.sb_lkid,
723 flags, &lksb->lksb_fsdlm, lksb);
724 return ret;
725}
726
727static int user_dlm_lock_status(struct ocfs2_dlm_lksb *lksb)
728{
729 return lksb->lksb_fsdlm.sb_status;
730}
731
732static int user_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb)
733{
734 int invalid = lksb->lksb_fsdlm.sb_flags & DLM_SBF_VALNOTVALID;
735
736 return !invalid;
737}
738
739static void *user_dlm_lvb(struct ocfs2_dlm_lksb *lksb)
740{
741 if (!lksb->lksb_fsdlm.sb_lvbptr)
742 lksb->lksb_fsdlm.sb_lvbptr = (char *)lksb +
743 sizeof(struct dlm_lksb);
744 return (void *)(lksb->lksb_fsdlm.sb_lvbptr);
745}
746
747static void user_dlm_dump_lksb(struct ocfs2_dlm_lksb *lksb)
748{
749}
750
751static int user_plock(struct ocfs2_cluster_connection *conn,
752 u64 ino,
753 struct file *file,
754 int cmd,
755 struct file_lock *fl)
756{
757 /*
758 * This more or less just demuxes the plock request into any
759 * one of three dlm calls.
760 *
761 * Internally, fs/dlm will pass these to a misc device, which
762 * a userspace daemon will read and write to.
763 *
764 * For now, cancel requests (which happen internally only),
765 * are turned into unlocks. Most of this function taken from
766 * gfs2_lock.
767 */
768
769 if (cmd == F_CANCELLK) {
770 cmd = F_SETLK;
771 fl->fl_type = F_UNLCK;
772 }
773
774 if (IS_GETLK(cmd))
775 return dlm_posix_get(conn->cc_lockspace, ino, file, fl);
776 else if (fl->fl_type == F_UNLCK)
777 return dlm_posix_unlock(conn->cc_lockspace, ino, file, fl);
778 else
779 return dlm_posix_lock(conn->cc_lockspace, ino, file, cmd, fl);
780}
781
782/*
783 * Compare a requested locking protocol version against the current one.
784 *
785 * If the major numbers are different, they are incompatible.
786 * If the current minor is greater than the request, they are incompatible.
787 * If the current minor is less than or equal to the request, they are
788 * compatible, and the requester should run at the current minor version.
789 */
790static int fs_protocol_compare(struct ocfs2_protocol_version *existing,
791 struct ocfs2_protocol_version *request)
792{
793 if (existing->pv_major != request->pv_major)
794 return 1;
795
796 if (existing->pv_minor > request->pv_minor)
797 return 1;
798
799 if (existing->pv_minor < request->pv_minor)
800 request->pv_minor = existing->pv_minor;
801
802 return 0;
803}
804
805static void lvb_to_version(char *lvb, struct ocfs2_protocol_version *ver)
806{
807 struct ocfs2_protocol_version *pv =
808 (struct ocfs2_protocol_version *)lvb;
809 /*
810 * ocfs2_protocol_version has two u8 variables, so we don't
811 * need any endian conversion.
812 */
813 ver->pv_major = pv->pv_major;
814 ver->pv_minor = pv->pv_minor;
815}
816
817static void version_to_lvb(struct ocfs2_protocol_version *ver, char *lvb)
818{
819 struct ocfs2_protocol_version *pv =
820 (struct ocfs2_protocol_version *)lvb;
821 /*
822 * ocfs2_protocol_version has two u8 variables, so we don't
823 * need any endian conversion.
824 */
825 pv->pv_major = ver->pv_major;
826 pv->pv_minor = ver->pv_minor;
827}
828
829static void sync_wait_cb(void *arg)
830{
831 struct ocfs2_cluster_connection *conn = arg;
832 struct ocfs2_live_connection *lc = conn->cc_private;
833 complete(&lc->oc_sync_wait);
834}
835
836static int sync_unlock(struct ocfs2_cluster_connection *conn,
837 struct dlm_lksb *lksb, char *name)
838{
839 int error;
840 struct ocfs2_live_connection *lc = conn->cc_private;
841
842 error = dlm_unlock(conn->cc_lockspace, lksb->sb_lkid, 0, lksb, conn);
843 if (error) {
844 printk(KERN_ERR "%s lkid %x error %d\n",
845 name, lksb->sb_lkid, error);
846 return error;
847 }
848
849 wait_for_completion(&lc->oc_sync_wait);
850
851 if (lksb->sb_status != -DLM_EUNLOCK) {
852 printk(KERN_ERR "%s lkid %x status %d\n",
853 name, lksb->sb_lkid, lksb->sb_status);
854 return -1;
855 }
856 return 0;
857}
858
859static int sync_lock(struct ocfs2_cluster_connection *conn,
860 int mode, uint32_t flags,
861 struct dlm_lksb *lksb, char *name)
862{
863 int error, status;
864 struct ocfs2_live_connection *lc = conn->cc_private;
865
866 error = dlm_lock(conn->cc_lockspace, mode, lksb, flags,
867 name, strlen(name),
868 0, sync_wait_cb, conn, NULL);
869 if (error) {
870 printk(KERN_ERR "%s lkid %x flags %x mode %d error %d\n",
871 name, lksb->sb_lkid, flags, mode, error);
872 return error;
873 }
874
875 wait_for_completion(&lc->oc_sync_wait);
876
877 status = lksb->sb_status;
878
879 if (status && status != -EAGAIN) {
880 printk(KERN_ERR "%s lkid %x flags %x mode %d status %d\n",
881 name, lksb->sb_lkid, flags, mode, status);
882 }
883
884 return status;
885}
886
887
888static int version_lock(struct ocfs2_cluster_connection *conn, int mode,
889 int flags)
890{
891 struct ocfs2_live_connection *lc = conn->cc_private;
892 return sync_lock(conn, mode, flags,
893 &lc->oc_version_lksb, VERSION_LOCK);
894}
895
896static int version_unlock(struct ocfs2_cluster_connection *conn)
897{
898 struct ocfs2_live_connection *lc = conn->cc_private;
899 return sync_unlock(conn, &lc->oc_version_lksb, VERSION_LOCK);
900}
901
902/* get_protocol_version()
903 *
904 * To exchange ocfs2 versioning, we use the LVB of the version dlm lock.
905 * The algorithm is:
906 * 1. Attempt to take the lock in EX mode (non-blocking).
907 * 2. If successful (which means it is the first mount), write the
908 * version number and downconvert to PR lock.
909 * 3. If unsuccessful (returns -EAGAIN), read the version from the LVB after
910 * taking the PR lock.
911 */
912
913static int get_protocol_version(struct ocfs2_cluster_connection *conn)
914{
915 int ret;
916 struct ocfs2_live_connection *lc = conn->cc_private;
917 struct ocfs2_protocol_version pv;
918
919 running_proto.pv_major =
920 ocfs2_user_plugin.sp_max_proto.pv_major;
921 running_proto.pv_minor =
922 ocfs2_user_plugin.sp_max_proto.pv_minor;
923
924 lc->oc_version_lksb.sb_lvbptr = lc->oc_lvb;
925 ret = version_lock(conn, DLM_LOCK_EX,
926 DLM_LKF_VALBLK|DLM_LKF_NOQUEUE);
927 if (!ret) {
928 conn->cc_version.pv_major = running_proto.pv_major;
929 conn->cc_version.pv_minor = running_proto.pv_minor;
930 version_to_lvb(&running_proto, lc->oc_lvb);
931 version_lock(conn, DLM_LOCK_PR, DLM_LKF_CONVERT|DLM_LKF_VALBLK);
932 } else if (ret == -EAGAIN) {
933 ret = version_lock(conn, DLM_LOCK_PR, DLM_LKF_VALBLK);
934 if (ret)
935 goto out;
936 lvb_to_version(lc->oc_lvb, &pv);
937
938 if ((pv.pv_major != running_proto.pv_major) ||
939 (pv.pv_minor > running_proto.pv_minor)) {
940 ret = -EINVAL;
941 goto out;
942 }
943
944 conn->cc_version.pv_major = pv.pv_major;
945 conn->cc_version.pv_minor = pv.pv_minor;
946 }
947out:
948 return ret;
949}
950
951static void user_recover_prep(void *arg)
952{
953}
954
955static void user_recover_slot(void *arg, struct dlm_slot *slot)
956{
957 struct ocfs2_cluster_connection *conn = arg;
958 printk(KERN_INFO "ocfs2: Node %d/%d down. Initiating recovery.\n",
959 slot->nodeid, slot->slot);
960 conn->cc_recovery_handler(slot->nodeid, conn->cc_recovery_data);
961
962}
963
964static void user_recover_done(void *arg, struct dlm_slot *slots,
965 int num_slots, int our_slot,
966 uint32_t generation)
967{
968 struct ocfs2_cluster_connection *conn = arg;
969 struct ocfs2_live_connection *lc = conn->cc_private;
970 int i;
971
972 for (i = 0; i < num_slots; i++)
973 if (slots[i].slot == our_slot) {
974 atomic_set(&lc->oc_this_node, slots[i].nodeid);
975 break;
976 }
977
978 lc->oc_our_slot = our_slot;
979 wake_up(&lc->oc_wait);
980}
981
982static const struct dlm_lockspace_ops ocfs2_ls_ops = {
983 .recover_prep = user_recover_prep,
984 .recover_slot = user_recover_slot,
985 .recover_done = user_recover_done,
986};
987
988static int user_cluster_disconnect(struct ocfs2_cluster_connection *conn)
989{
990 version_unlock(conn);
991 dlm_release_lockspace(conn->cc_lockspace, 2);
992 conn->cc_lockspace = NULL;
993 ocfs2_live_connection_drop(conn->cc_private);
994 conn->cc_private = NULL;
995 return 0;
996}
997
998static int user_cluster_connect(struct ocfs2_cluster_connection *conn)
999{
1000 dlm_lockspace_t *fsdlm;
1001 struct ocfs2_live_connection *lc;
1002 int rc, ops_rv;
1003
1004 BUG_ON(conn == NULL);
1005
1006 lc = kzalloc(sizeof(struct ocfs2_live_connection), GFP_KERNEL);
1007 if (!lc) {
1008 rc = -ENOMEM;
1009 goto out;
1010 }
1011
1012 init_waitqueue_head(&lc->oc_wait);
1013 init_completion(&lc->oc_sync_wait);
1014 atomic_set(&lc->oc_this_node, 0);
1015 conn->cc_private = lc;
1016 lc->oc_type = NO_CONTROLD;
1017
1018 rc = dlm_new_lockspace(conn->cc_name, conn->cc_cluster_name,
1019 DLM_LSFL_FS, DLM_LVB_LEN,
1020 &ocfs2_ls_ops, conn, &ops_rv, &fsdlm);
1021 if (rc)
1022 goto out;
1023
1024 if (ops_rv == -EOPNOTSUPP) {
1025 lc->oc_type = WITH_CONTROLD;
1026 printk(KERN_NOTICE "ocfs2: You seem to be using an older "
1027 "version of dlm_controld and/or ocfs2-tools."
1028 " Please consider upgrading.\n");
1029 } else if (ops_rv) {
1030 rc = ops_rv;
1031 goto out;
1032 }
1033 conn->cc_lockspace = fsdlm;
1034
1035 rc = ocfs2_live_connection_attach(conn, lc);
1036 if (rc)
1037 goto out;
1038
1039 if (lc->oc_type == NO_CONTROLD) {
1040 rc = get_protocol_version(conn);
1041 if (rc) {
1042 printk(KERN_ERR "ocfs2: Could not determine"
1043 " locking version\n");
1044 user_cluster_disconnect(conn);
1045 goto out;
1046 }
1047 wait_event(lc->oc_wait, (atomic_read(&lc->oc_this_node) > 0));
1048 }
1049
1050 /*
1051 * running_proto must have been set before we allowed any mounts
1052 * to proceed.
1053 */
1054 if (fs_protocol_compare(&running_proto, &conn->cc_version)) {
1055 printk(KERN_ERR
1056 "Unable to mount with fs locking protocol version "
1057 "%u.%u because negotiated protocol is %u.%u\n",
1058 conn->cc_version.pv_major, conn->cc_version.pv_minor,
1059 running_proto.pv_major, running_proto.pv_minor);
1060 rc = -EPROTO;
1061 ocfs2_live_connection_drop(lc);
1062 lc = NULL;
1063 }
1064
1065out:
1066 if (rc && lc)
1067 kfree(lc);
1068 return rc;
1069}
1070
1071
1072static int user_cluster_this_node(struct ocfs2_cluster_connection *conn,
1073 unsigned int *this_node)
1074{
1075 int rc;
1076 struct ocfs2_live_connection *lc = conn->cc_private;
1077
1078 if (lc->oc_type == WITH_CONTROLD)
1079 rc = ocfs2_control_get_this_node();
1080 else if (lc->oc_type == NO_CONTROLD)
1081 rc = atomic_read(&lc->oc_this_node);
1082 else
1083 rc = -EINVAL;
1084
1085 if (rc < 0)
1086 return rc;
1087
1088 *this_node = rc;
1089 return 0;
1090}
1091
1092static struct ocfs2_stack_operations ocfs2_user_plugin_ops = {
1093 .connect = user_cluster_connect,
1094 .disconnect = user_cluster_disconnect,
1095 .this_node = user_cluster_this_node,
1096 .dlm_lock = user_dlm_lock,
1097 .dlm_unlock = user_dlm_unlock,
1098 .lock_status = user_dlm_lock_status,
1099 .lvb_valid = user_dlm_lvb_valid,
1100 .lock_lvb = user_dlm_lvb,
1101 .plock = user_plock,
1102 .dump_lksb = user_dlm_dump_lksb,
1103};
1104
1105static struct ocfs2_stack_plugin ocfs2_user_plugin = {
1106 .sp_name = "user",
1107 .sp_ops = &ocfs2_user_plugin_ops,
1108 .sp_owner = THIS_MODULE,
1109};
1110
1111
1112static int __init ocfs2_user_plugin_init(void)
1113{
1114 int rc;
1115
1116 rc = ocfs2_control_init();
1117 if (!rc) {
1118 rc = ocfs2_stack_glue_register(&ocfs2_user_plugin);
1119 if (rc)
1120 ocfs2_control_exit();
1121 }
1122
1123 return rc;
1124}
1125
1126static void __exit ocfs2_user_plugin_exit(void)
1127{
1128 ocfs2_stack_glue_unregister(&ocfs2_user_plugin);
1129 ocfs2_control_exit();
1130}
1131
1132MODULE_AUTHOR("Oracle");
1133MODULE_DESCRIPTION("ocfs2 driver for userspace cluster stacks");
1134MODULE_LICENSE("GPL");
1135module_init(ocfs2_user_plugin_init);
1136module_exit(ocfs2_user_plugin_exit);
1// SPDX-License-Identifier: GPL-2.0-only
2/* -*- mode: c; c-basic-offset: 8; -*-
3 * vim: noexpandtab sw=8 ts=8 sts=0:
4 *
5 * stack_user.c
6 *
7 * Code which interfaces ocfs2 with fs/dlm and a userspace stack.
8 *
9 * Copyright (C) 2007 Oracle. All rights reserved.
10 */
11
12#include <linux/module.h>
13#include <linux/fs.h>
14#include <linux/miscdevice.h>
15#include <linux/mutex.h>
16#include <linux/slab.h>
17#include <linux/reboot.h>
18#include <linux/sched.h>
19#include <linux/uaccess.h>
20
21#include "stackglue.h"
22
23#include <linux/dlm_plock.h>
24
25/*
26 * The control protocol starts with a handshake. Until the handshake
27 * is complete, the control device will fail all write(2)s.
28 *
29 * The handshake is simple. First, the client reads until EOF. Each line
30 * of output is a supported protocol tag. All protocol tags are a single
31 * character followed by a two hex digit version number. Currently the
32 * only things supported is T01, for "Text-base version 0x01". Next, the
33 * client writes the version they would like to use, including the newline.
34 * Thus, the protocol tag is 'T01\n'. If the version tag written is
35 * unknown, -EINVAL is returned. Once the negotiation is complete, the
36 * client can start sending messages.
37 *
38 * The T01 protocol has three messages. First is the "SETN" message.
39 * It has the following syntax:
40 *
41 * SETN<space><8-char-hex-nodenum><newline>
42 *
43 * This is 14 characters.
44 *
45 * The "SETN" message must be the first message following the protocol.
46 * It tells ocfs2_control the local node number.
47 *
48 * Next comes the "SETV" message. It has the following syntax:
49 *
50 * SETV<space><2-char-hex-major><space><2-char-hex-minor><newline>
51 *
52 * This is 11 characters.
53 *
54 * The "SETV" message sets the filesystem locking protocol version as
55 * negotiated by the client. The client negotiates based on the maximum
56 * version advertised in /sys/fs/ocfs2/max_locking_protocol. The major
57 * number from the "SETV" message must match
58 * ocfs2_user_plugin.sp_max_proto.pv_major, and the minor number
59 * must be less than or equal to ...sp_max_version.pv_minor.
60 *
61 * Once this information has been set, mounts will be allowed. From this
62 * point on, the "DOWN" message can be sent for node down notification.
63 * It has the following syntax:
64 *
65 * DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline>
66 *
67 * eg:
68 *
69 * DOWN 632A924FDD844190BDA93C0DF6B94899 00000001\n
70 *
71 * This is 47 characters.
72 */
73
74/*
75 * Whether or not the client has done the handshake.
76 * For now, we have just one protocol version.
77 */
78#define OCFS2_CONTROL_PROTO "T01\n"
79#define OCFS2_CONTROL_PROTO_LEN 4
80
81/* Handshake states */
82#define OCFS2_CONTROL_HANDSHAKE_INVALID (0)
83#define OCFS2_CONTROL_HANDSHAKE_READ (1)
84#define OCFS2_CONTROL_HANDSHAKE_PROTOCOL (2)
85#define OCFS2_CONTROL_HANDSHAKE_VALID (3)
86
87/* Messages */
88#define OCFS2_CONTROL_MESSAGE_OP_LEN 4
89#define OCFS2_CONTROL_MESSAGE_SETNODE_OP "SETN"
90#define OCFS2_CONTROL_MESSAGE_SETNODE_TOTAL_LEN 14
91#define OCFS2_CONTROL_MESSAGE_SETVERSION_OP "SETV"
92#define OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN 11
93#define OCFS2_CONTROL_MESSAGE_DOWN_OP "DOWN"
94#define OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN 47
95#define OCFS2_TEXT_UUID_LEN 32
96#define OCFS2_CONTROL_MESSAGE_VERNUM_LEN 2
97#define OCFS2_CONTROL_MESSAGE_NODENUM_LEN 8
98#define VERSION_LOCK "version_lock"
99
100enum ocfs2_connection_type {
101 WITH_CONTROLD,
102 NO_CONTROLD
103};
104
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 */
109struct ocfs2_live_connection {
110 struct list_head oc_list;
111 struct ocfs2_cluster_connection *oc_conn;
112 enum ocfs2_connection_type oc_type;
113 atomic_t oc_this_node;
114 int oc_our_slot;
115 struct dlm_lksb oc_version_lksb;
116 char oc_lvb[DLM_LVB_LEN];
117 struct completion oc_sync_wait;
118 wait_queue_head_t oc_wait;
119};
120
121struct ocfs2_control_private {
122 struct list_head op_list;
123 int op_state;
124 int op_this_node;
125 struct ocfs2_protocol_version op_proto;
126};
127
128/* SETN<space><8-char-hex-nodenum><newline> */
129struct ocfs2_control_message_setn {
130 char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
131 char space;
132 char nodestr[OCFS2_CONTROL_MESSAGE_NODENUM_LEN];
133 char newline;
134};
135
136/* SETV<space><2-char-hex-major><space><2-char-hex-minor><newline> */
137struct ocfs2_control_message_setv {
138 char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
139 char space1;
140 char major[OCFS2_CONTROL_MESSAGE_VERNUM_LEN];
141 char space2;
142 char minor[OCFS2_CONTROL_MESSAGE_VERNUM_LEN];
143 char newline;
144};
145
146/* DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline> */
147struct ocfs2_control_message_down {
148 char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
149 char space1;
150 char uuid[OCFS2_TEXT_UUID_LEN];
151 char space2;
152 char nodestr[OCFS2_CONTROL_MESSAGE_NODENUM_LEN];
153 char newline;
154};
155
156union ocfs2_control_message {
157 char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
158 struct ocfs2_control_message_setn u_setn;
159 struct ocfs2_control_message_setv u_setv;
160 struct ocfs2_control_message_down u_down;
161};
162
163static struct ocfs2_stack_plugin ocfs2_user_plugin;
164
165static atomic_t ocfs2_control_opened;
166static int ocfs2_control_this_node = -1;
167static struct ocfs2_protocol_version running_proto;
168
169static LIST_HEAD(ocfs2_live_connection_list);
170static LIST_HEAD(ocfs2_control_private_list);
171static DEFINE_MUTEX(ocfs2_control_lock);
172
173static inline void ocfs2_control_set_handshake_state(struct file *file,
174 int state)
175{
176 struct ocfs2_control_private *p = file->private_data;
177 p->op_state = state;
178}
179
180static inline int ocfs2_control_get_handshake_state(struct file *file)
181{
182 struct ocfs2_control_private *p = file->private_data;
183 return p->op_state;
184}
185
186static struct ocfs2_live_connection *ocfs2_connection_find(const char *name)
187{
188 size_t len = strlen(name);
189 struct ocfs2_live_connection *c;
190
191 BUG_ON(!mutex_is_locked(&ocfs2_control_lock));
192
193 list_for_each_entry(c, &ocfs2_live_connection_list, oc_list) {
194 if ((c->oc_conn->cc_namelen == len) &&
195 !strncmp(c->oc_conn->cc_name, name, len))
196 return c;
197 }
198
199 return NULL;
200}
201
202/*
203 * ocfs2_live_connection structures are created underneath the ocfs2
204 * mount path. Since the VFS prevents multiple calls to
205 * fill_super(), we can't get dupes here.
206 */
207static int ocfs2_live_connection_attach(struct ocfs2_cluster_connection *conn,
208 struct ocfs2_live_connection *c)
209{
210 int rc = 0;
211
212 mutex_lock(&ocfs2_control_lock);
213 c->oc_conn = conn;
214
215 if ((c->oc_type == NO_CONTROLD) || atomic_read(&ocfs2_control_opened))
216 list_add(&c->oc_list, &ocfs2_live_connection_list);
217 else {
218 printk(KERN_ERR
219 "ocfs2: Userspace control daemon is not present\n");
220 rc = -ESRCH;
221 }
222
223 mutex_unlock(&ocfs2_control_lock);
224 return rc;
225}
226
227/*
228 * This function disconnects the cluster connection from ocfs2_control.
229 * Afterwards, userspace can't affect the cluster connection.
230 */
231static void ocfs2_live_connection_drop(struct ocfs2_live_connection *c)
232{
233 mutex_lock(&ocfs2_control_lock);
234 list_del_init(&c->oc_list);
235 c->oc_conn = NULL;
236 mutex_unlock(&ocfs2_control_lock);
237
238 kfree(c);
239}
240
241static int ocfs2_control_cfu(void *target, size_t target_len,
242 const char __user *buf, size_t count)
243{
244 /* The T01 expects write(2) calls to have exactly one command */
245 if ((count != target_len) ||
246 (count > sizeof(union ocfs2_control_message)))
247 return -EINVAL;
248
249 if (copy_from_user(target, buf, target_len))
250 return -EFAULT;
251
252 return 0;
253}
254
255static ssize_t ocfs2_control_validate_protocol(struct file *file,
256 const char __user *buf,
257 size_t count)
258{
259 ssize_t ret;
260 char kbuf[OCFS2_CONTROL_PROTO_LEN];
261
262 ret = ocfs2_control_cfu(kbuf, OCFS2_CONTROL_PROTO_LEN,
263 buf, count);
264 if (ret)
265 return ret;
266
267 if (strncmp(kbuf, OCFS2_CONTROL_PROTO, OCFS2_CONTROL_PROTO_LEN))
268 return -EINVAL;
269
270 ocfs2_control_set_handshake_state(file,
271 OCFS2_CONTROL_HANDSHAKE_PROTOCOL);
272
273 return count;
274}
275
276static void ocfs2_control_send_down(const char *uuid,
277 int nodenum)
278{
279 struct ocfs2_live_connection *c;
280
281 mutex_lock(&ocfs2_control_lock);
282
283 c = ocfs2_connection_find(uuid);
284 if (c) {
285 BUG_ON(c->oc_conn == NULL);
286 c->oc_conn->cc_recovery_handler(nodenum,
287 c->oc_conn->cc_recovery_data);
288 }
289
290 mutex_unlock(&ocfs2_control_lock);
291}
292
293/*
294 * Called whenever configuration elements are sent to /dev/ocfs2_control.
295 * If all configuration elements are present, try to set the global
296 * values. If there is a problem, return an error. Skip any missing
297 * elements, and only bump ocfs2_control_opened when we have all elements
298 * and are successful.
299 */
300static int ocfs2_control_install_private(struct file *file)
301{
302 int rc = 0;
303 int set_p = 1;
304 struct ocfs2_control_private *p = file->private_data;
305
306 BUG_ON(p->op_state != OCFS2_CONTROL_HANDSHAKE_PROTOCOL);
307
308 mutex_lock(&ocfs2_control_lock);
309
310 if (p->op_this_node < 0) {
311 set_p = 0;
312 } else if ((ocfs2_control_this_node >= 0) &&
313 (ocfs2_control_this_node != p->op_this_node)) {
314 rc = -EINVAL;
315 goto out_unlock;
316 }
317
318 if (!p->op_proto.pv_major) {
319 set_p = 0;
320 } else if (!list_empty(&ocfs2_live_connection_list) &&
321 ((running_proto.pv_major != p->op_proto.pv_major) ||
322 (running_proto.pv_minor != p->op_proto.pv_minor))) {
323 rc = -EINVAL;
324 goto out_unlock;
325 }
326
327 if (set_p) {
328 ocfs2_control_this_node = p->op_this_node;
329 running_proto.pv_major = p->op_proto.pv_major;
330 running_proto.pv_minor = p->op_proto.pv_minor;
331 }
332
333out_unlock:
334 mutex_unlock(&ocfs2_control_lock);
335
336 if (!rc && set_p) {
337 /* We set the global values successfully */
338 atomic_inc(&ocfs2_control_opened);
339 ocfs2_control_set_handshake_state(file,
340 OCFS2_CONTROL_HANDSHAKE_VALID);
341 }
342
343 return rc;
344}
345
346static int ocfs2_control_get_this_node(void)
347{
348 int rc;
349
350 mutex_lock(&ocfs2_control_lock);
351 if (ocfs2_control_this_node < 0)
352 rc = -EINVAL;
353 else
354 rc = ocfs2_control_this_node;
355 mutex_unlock(&ocfs2_control_lock);
356
357 return rc;
358}
359
360static int ocfs2_control_do_setnode_msg(struct file *file,
361 struct ocfs2_control_message_setn *msg)
362{
363 long nodenum;
364 char *ptr = NULL;
365 struct ocfs2_control_private *p = file->private_data;
366
367 if (ocfs2_control_get_handshake_state(file) !=
368 OCFS2_CONTROL_HANDSHAKE_PROTOCOL)
369 return -EINVAL;
370
371 if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_SETNODE_OP,
372 OCFS2_CONTROL_MESSAGE_OP_LEN))
373 return -EINVAL;
374
375 if ((msg->space != ' ') || (msg->newline != '\n'))
376 return -EINVAL;
377 msg->space = msg->newline = '\0';
378
379 nodenum = simple_strtol(msg->nodestr, &ptr, 16);
380 if (!ptr || *ptr)
381 return -EINVAL;
382
383 if ((nodenum == LONG_MIN) || (nodenum == LONG_MAX) ||
384 (nodenum > INT_MAX) || (nodenum < 0))
385 return -ERANGE;
386 p->op_this_node = nodenum;
387
388 return ocfs2_control_install_private(file);
389}
390
391static int ocfs2_control_do_setversion_msg(struct file *file,
392 struct ocfs2_control_message_setv *msg)
393{
394 long major, minor;
395 char *ptr = NULL;
396 struct ocfs2_control_private *p = file->private_data;
397 struct ocfs2_protocol_version *max =
398 &ocfs2_user_plugin.sp_max_proto;
399
400 if (ocfs2_control_get_handshake_state(file) !=
401 OCFS2_CONTROL_HANDSHAKE_PROTOCOL)
402 return -EINVAL;
403
404 if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP,
405 OCFS2_CONTROL_MESSAGE_OP_LEN))
406 return -EINVAL;
407
408 if ((msg->space1 != ' ') || (msg->space2 != ' ') ||
409 (msg->newline != '\n'))
410 return -EINVAL;
411 msg->space1 = msg->space2 = msg->newline = '\0';
412
413 major = simple_strtol(msg->major, &ptr, 16);
414 if (!ptr || *ptr)
415 return -EINVAL;
416 minor = simple_strtol(msg->minor, &ptr, 16);
417 if (!ptr || *ptr)
418 return -EINVAL;
419
420 /*
421 * The major must be between 1 and 255, inclusive. The minor
422 * must be between 0 and 255, inclusive. The version passed in
423 * must be within the maximum version supported by the filesystem.
424 */
425 if ((major == LONG_MIN) || (major == LONG_MAX) ||
426 (major > (u8)-1) || (major < 1))
427 return -ERANGE;
428 if ((minor == LONG_MIN) || (minor == LONG_MAX) ||
429 (minor > (u8)-1) || (minor < 0))
430 return -ERANGE;
431 if ((major != max->pv_major) ||
432 (minor > max->pv_minor))
433 return -EINVAL;
434
435 p->op_proto.pv_major = major;
436 p->op_proto.pv_minor = minor;
437
438 return ocfs2_control_install_private(file);
439}
440
441static int ocfs2_control_do_down_msg(struct file *file,
442 struct ocfs2_control_message_down *msg)
443{
444 long nodenum;
445 char *p = NULL;
446
447 if (ocfs2_control_get_handshake_state(file) !=
448 OCFS2_CONTROL_HANDSHAKE_VALID)
449 return -EINVAL;
450
451 if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_DOWN_OP,
452 OCFS2_CONTROL_MESSAGE_OP_LEN))
453 return -EINVAL;
454
455 if ((msg->space1 != ' ') || (msg->space2 != ' ') ||
456 (msg->newline != '\n'))
457 return -EINVAL;
458 msg->space1 = msg->space2 = msg->newline = '\0';
459
460 nodenum = simple_strtol(msg->nodestr, &p, 16);
461 if (!p || *p)
462 return -EINVAL;
463
464 if ((nodenum == LONG_MIN) || (nodenum == LONG_MAX) ||
465 (nodenum > INT_MAX) || (nodenum < 0))
466 return -ERANGE;
467
468 ocfs2_control_send_down(msg->uuid, nodenum);
469
470 return 0;
471}
472
473static ssize_t ocfs2_control_message(struct file *file,
474 const char __user *buf,
475 size_t count)
476{
477 ssize_t ret;
478 union ocfs2_control_message msg;
479
480 /* Try to catch padding issues */
481 WARN_ON(offsetof(struct ocfs2_control_message_down, uuid) !=
482 (sizeof(msg.u_down.tag) + sizeof(msg.u_down.space1)));
483
484 memset(&msg, 0, sizeof(union ocfs2_control_message));
485 ret = ocfs2_control_cfu(&msg, count, buf, count);
486 if (ret)
487 goto out;
488
489 if ((count == OCFS2_CONTROL_MESSAGE_SETNODE_TOTAL_LEN) &&
490 !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETNODE_OP,
491 OCFS2_CONTROL_MESSAGE_OP_LEN))
492 ret = ocfs2_control_do_setnode_msg(file, &msg.u_setn);
493 else if ((count == OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN) &&
494 !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP,
495 OCFS2_CONTROL_MESSAGE_OP_LEN))
496 ret = ocfs2_control_do_setversion_msg(file, &msg.u_setv);
497 else if ((count == OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN) &&
498 !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_DOWN_OP,
499 OCFS2_CONTROL_MESSAGE_OP_LEN))
500 ret = ocfs2_control_do_down_msg(file, &msg.u_down);
501 else
502 ret = -EINVAL;
503
504out:
505 return ret ? ret : count;
506}
507
508static ssize_t ocfs2_control_write(struct file *file,
509 const char __user *buf,
510 size_t count,
511 loff_t *ppos)
512{
513 ssize_t ret;
514
515 switch (ocfs2_control_get_handshake_state(file)) {
516 case OCFS2_CONTROL_HANDSHAKE_INVALID:
517 ret = -EINVAL;
518 break;
519
520 case OCFS2_CONTROL_HANDSHAKE_READ:
521 ret = ocfs2_control_validate_protocol(file, buf,
522 count);
523 break;
524
525 case OCFS2_CONTROL_HANDSHAKE_PROTOCOL:
526 case OCFS2_CONTROL_HANDSHAKE_VALID:
527 ret = ocfs2_control_message(file, buf, count);
528 break;
529
530 default:
531 BUG();
532 ret = -EIO;
533 break;
534 }
535
536 return ret;
537}
538
539/*
540 * This is a naive version. If we ever have a new protocol, we'll expand
541 * it. Probably using seq_file.
542 */
543static ssize_t ocfs2_control_read(struct file *file,
544 char __user *buf,
545 size_t count,
546 loff_t *ppos)
547{
548 ssize_t ret;
549
550 ret = simple_read_from_buffer(buf, count, ppos,
551 OCFS2_CONTROL_PROTO, OCFS2_CONTROL_PROTO_LEN);
552
553 /* Have we read the whole protocol list? */
554 if (ret > 0 && *ppos >= OCFS2_CONTROL_PROTO_LEN)
555 ocfs2_control_set_handshake_state(file,
556 OCFS2_CONTROL_HANDSHAKE_READ);
557
558 return ret;
559}
560
561static int ocfs2_control_release(struct inode *inode, struct file *file)
562{
563 struct ocfs2_control_private *p = file->private_data;
564
565 mutex_lock(&ocfs2_control_lock);
566
567 if (ocfs2_control_get_handshake_state(file) !=
568 OCFS2_CONTROL_HANDSHAKE_VALID)
569 goto out;
570
571 if (atomic_dec_and_test(&ocfs2_control_opened)) {
572 if (!list_empty(&ocfs2_live_connection_list)) {
573 /* XXX: Do bad things! */
574 printk(KERN_ERR
575 "ocfs2: Unexpected release of ocfs2_control!\n"
576 " Loss of cluster connection requires "
577 "an emergency restart!\n");
578 emergency_restart();
579 }
580 /*
581 * Last valid close clears the node number and resets
582 * the locking protocol version
583 */
584 ocfs2_control_this_node = -1;
585 running_proto.pv_major = 0;
586 running_proto.pv_minor = 0;
587 }
588
589out:
590 list_del_init(&p->op_list);
591 file->private_data = NULL;
592
593 mutex_unlock(&ocfs2_control_lock);
594
595 kfree(p);
596
597 return 0;
598}
599
600static int ocfs2_control_open(struct inode *inode, struct file *file)
601{
602 struct ocfs2_control_private *p;
603
604 p = kzalloc(sizeof(struct ocfs2_control_private), GFP_KERNEL);
605 if (!p)
606 return -ENOMEM;
607 p->op_this_node = -1;
608
609 mutex_lock(&ocfs2_control_lock);
610 file->private_data = p;
611 list_add(&p->op_list, &ocfs2_control_private_list);
612 mutex_unlock(&ocfs2_control_lock);
613
614 return 0;
615}
616
617static const struct file_operations ocfs2_control_fops = {
618 .open = ocfs2_control_open,
619 .release = ocfs2_control_release,
620 .read = ocfs2_control_read,
621 .write = ocfs2_control_write,
622 .owner = THIS_MODULE,
623 .llseek = default_llseek,
624};
625
626static struct miscdevice ocfs2_control_device = {
627 .minor = MISC_DYNAMIC_MINOR,
628 .name = "ocfs2_control",
629 .fops = &ocfs2_control_fops,
630};
631
632static int ocfs2_control_init(void)
633{
634 int rc;
635
636 atomic_set(&ocfs2_control_opened, 0);
637
638 rc = misc_register(&ocfs2_control_device);
639 if (rc)
640 printk(KERN_ERR
641 "ocfs2: Unable to register ocfs2_control device "
642 "(errno %d)\n",
643 -rc);
644
645 return rc;
646}
647
648static void ocfs2_control_exit(void)
649{
650 misc_deregister(&ocfs2_control_device);
651}
652
653static void fsdlm_lock_ast_wrapper(void *astarg)
654{
655 struct ocfs2_dlm_lksb *lksb = astarg;
656 int status = lksb->lksb_fsdlm.sb_status;
657
658 /*
659 * For now we're punting on the issue of other non-standard errors
660 * where we can't tell if the unlock_ast or lock_ast should be called.
661 * The main "other error" that's possible is EINVAL which means the
662 * function was called with invalid args, which shouldn't be possible
663 * since the caller here is under our control. Other non-standard
664 * errors probably fall into the same category, or otherwise are fatal
665 * which means we can't carry on anyway.
666 */
667
668 if (status == -DLM_EUNLOCK || status == -DLM_ECANCEL)
669 lksb->lksb_conn->cc_proto->lp_unlock_ast(lksb, 0);
670 else
671 lksb->lksb_conn->cc_proto->lp_lock_ast(lksb);
672}
673
674static void fsdlm_blocking_ast_wrapper(void *astarg, int level)
675{
676 struct ocfs2_dlm_lksb *lksb = astarg;
677
678 lksb->lksb_conn->cc_proto->lp_blocking_ast(lksb, level);
679}
680
681static int user_dlm_lock(struct ocfs2_cluster_connection *conn,
682 int mode,
683 struct ocfs2_dlm_lksb *lksb,
684 u32 flags,
685 void *name,
686 unsigned int namelen)
687{
688 int ret;
689
690 if (!lksb->lksb_fsdlm.sb_lvbptr)
691 lksb->lksb_fsdlm.sb_lvbptr = (char *)lksb +
692 sizeof(struct dlm_lksb);
693
694 ret = dlm_lock(conn->cc_lockspace, mode, &lksb->lksb_fsdlm,
695 flags|DLM_LKF_NODLCKWT, name, namelen, 0,
696 fsdlm_lock_ast_wrapper, lksb,
697 fsdlm_blocking_ast_wrapper);
698 return ret;
699}
700
701static int user_dlm_unlock(struct ocfs2_cluster_connection *conn,
702 struct ocfs2_dlm_lksb *lksb,
703 u32 flags)
704{
705 int ret;
706
707 ret = dlm_unlock(conn->cc_lockspace, lksb->lksb_fsdlm.sb_lkid,
708 flags, &lksb->lksb_fsdlm, lksb);
709 return ret;
710}
711
712static int user_dlm_lock_status(struct ocfs2_dlm_lksb *lksb)
713{
714 return lksb->lksb_fsdlm.sb_status;
715}
716
717static int user_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb)
718{
719 int invalid = lksb->lksb_fsdlm.sb_flags & DLM_SBF_VALNOTVALID;
720
721 return !invalid;
722}
723
724static void *user_dlm_lvb(struct ocfs2_dlm_lksb *lksb)
725{
726 if (!lksb->lksb_fsdlm.sb_lvbptr)
727 lksb->lksb_fsdlm.sb_lvbptr = (char *)lksb +
728 sizeof(struct dlm_lksb);
729 return (void *)(lksb->lksb_fsdlm.sb_lvbptr);
730}
731
732static void user_dlm_dump_lksb(struct ocfs2_dlm_lksb *lksb)
733{
734}
735
736static int user_plock(struct ocfs2_cluster_connection *conn,
737 u64 ino,
738 struct file *file,
739 int cmd,
740 struct file_lock *fl)
741{
742 /*
743 * This more or less just demuxes the plock request into any
744 * one of three dlm calls.
745 *
746 * Internally, fs/dlm will pass these to a misc device, which
747 * a userspace daemon will read and write to.
748 *
749 * For now, cancel requests (which happen internally only),
750 * are turned into unlocks. Most of this function taken from
751 * gfs2_lock.
752 */
753
754 if (cmd == F_CANCELLK) {
755 cmd = F_SETLK;
756 fl->fl_type = F_UNLCK;
757 }
758
759 if (IS_GETLK(cmd))
760 return dlm_posix_get(conn->cc_lockspace, ino, file, fl);
761 else if (fl->fl_type == F_UNLCK)
762 return dlm_posix_unlock(conn->cc_lockspace, ino, file, fl);
763 else
764 return dlm_posix_lock(conn->cc_lockspace, ino, file, cmd, fl);
765}
766
767/*
768 * Compare a requested locking protocol version against the current one.
769 *
770 * If the major numbers are different, they are incompatible.
771 * If the current minor is greater than the request, they are incompatible.
772 * If the current minor is less than or equal to the request, they are
773 * compatible, and the requester should run at the current minor version.
774 */
775static int fs_protocol_compare(struct ocfs2_protocol_version *existing,
776 struct ocfs2_protocol_version *request)
777{
778 if (existing->pv_major != request->pv_major)
779 return 1;
780
781 if (existing->pv_minor > request->pv_minor)
782 return 1;
783
784 if (existing->pv_minor < request->pv_minor)
785 request->pv_minor = existing->pv_minor;
786
787 return 0;
788}
789
790static void lvb_to_version(char *lvb, struct ocfs2_protocol_version *ver)
791{
792 struct ocfs2_protocol_version *pv =
793 (struct ocfs2_protocol_version *)lvb;
794 /*
795 * ocfs2_protocol_version has two u8 variables, so we don't
796 * need any endian conversion.
797 */
798 ver->pv_major = pv->pv_major;
799 ver->pv_minor = pv->pv_minor;
800}
801
802static void version_to_lvb(struct ocfs2_protocol_version *ver, char *lvb)
803{
804 struct ocfs2_protocol_version *pv =
805 (struct ocfs2_protocol_version *)lvb;
806 /*
807 * ocfs2_protocol_version has two u8 variables, so we don't
808 * need any endian conversion.
809 */
810 pv->pv_major = ver->pv_major;
811 pv->pv_minor = ver->pv_minor;
812}
813
814static void sync_wait_cb(void *arg)
815{
816 struct ocfs2_cluster_connection *conn = arg;
817 struct ocfs2_live_connection *lc = conn->cc_private;
818 complete(&lc->oc_sync_wait);
819}
820
821static int sync_unlock(struct ocfs2_cluster_connection *conn,
822 struct dlm_lksb *lksb, char *name)
823{
824 int error;
825 struct ocfs2_live_connection *lc = conn->cc_private;
826
827 error = dlm_unlock(conn->cc_lockspace, lksb->sb_lkid, 0, lksb, conn);
828 if (error) {
829 printk(KERN_ERR "%s lkid %x error %d\n",
830 name, lksb->sb_lkid, error);
831 return error;
832 }
833
834 wait_for_completion(&lc->oc_sync_wait);
835
836 if (lksb->sb_status != -DLM_EUNLOCK) {
837 printk(KERN_ERR "%s lkid %x status %d\n",
838 name, lksb->sb_lkid, lksb->sb_status);
839 return -1;
840 }
841 return 0;
842}
843
844static int sync_lock(struct ocfs2_cluster_connection *conn,
845 int mode, uint32_t flags,
846 struct dlm_lksb *lksb, char *name)
847{
848 int error, status;
849 struct ocfs2_live_connection *lc = conn->cc_private;
850
851 error = dlm_lock(conn->cc_lockspace, mode, lksb, flags,
852 name, strlen(name),
853 0, sync_wait_cb, conn, NULL);
854 if (error) {
855 printk(KERN_ERR "%s lkid %x flags %x mode %d error %d\n",
856 name, lksb->sb_lkid, flags, mode, error);
857 return error;
858 }
859
860 wait_for_completion(&lc->oc_sync_wait);
861
862 status = lksb->sb_status;
863
864 if (status && status != -EAGAIN) {
865 printk(KERN_ERR "%s lkid %x flags %x mode %d status %d\n",
866 name, lksb->sb_lkid, flags, mode, status);
867 }
868
869 return status;
870}
871
872
873static int version_lock(struct ocfs2_cluster_connection *conn, int mode,
874 int flags)
875{
876 struct ocfs2_live_connection *lc = conn->cc_private;
877 return sync_lock(conn, mode, flags,
878 &lc->oc_version_lksb, VERSION_LOCK);
879}
880
881static int version_unlock(struct ocfs2_cluster_connection *conn)
882{
883 struct ocfs2_live_connection *lc = conn->cc_private;
884 return sync_unlock(conn, &lc->oc_version_lksb, VERSION_LOCK);
885}
886
887/* get_protocol_version()
888 *
889 * To exchange ocfs2 versioning, we use the LVB of the version dlm lock.
890 * The algorithm is:
891 * 1. Attempt to take the lock in EX mode (non-blocking).
892 * 2. If successful (which means it is the first mount), write the
893 * version number and downconvert to PR lock.
894 * 3. If unsuccessful (returns -EAGAIN), read the version from the LVB after
895 * taking the PR lock.
896 */
897
898static int get_protocol_version(struct ocfs2_cluster_connection *conn)
899{
900 int ret;
901 struct ocfs2_live_connection *lc = conn->cc_private;
902 struct ocfs2_protocol_version pv;
903
904 running_proto.pv_major =
905 ocfs2_user_plugin.sp_max_proto.pv_major;
906 running_proto.pv_minor =
907 ocfs2_user_plugin.sp_max_proto.pv_minor;
908
909 lc->oc_version_lksb.sb_lvbptr = lc->oc_lvb;
910 ret = version_lock(conn, DLM_LOCK_EX,
911 DLM_LKF_VALBLK|DLM_LKF_NOQUEUE);
912 if (!ret) {
913 conn->cc_version.pv_major = running_proto.pv_major;
914 conn->cc_version.pv_minor = running_proto.pv_minor;
915 version_to_lvb(&running_proto, lc->oc_lvb);
916 version_lock(conn, DLM_LOCK_PR, DLM_LKF_CONVERT|DLM_LKF_VALBLK);
917 } else if (ret == -EAGAIN) {
918 ret = version_lock(conn, DLM_LOCK_PR, DLM_LKF_VALBLK);
919 if (ret)
920 goto out;
921 lvb_to_version(lc->oc_lvb, &pv);
922
923 if ((pv.pv_major != running_proto.pv_major) ||
924 (pv.pv_minor > running_proto.pv_minor)) {
925 ret = -EINVAL;
926 goto out;
927 }
928
929 conn->cc_version.pv_major = pv.pv_major;
930 conn->cc_version.pv_minor = pv.pv_minor;
931 }
932out:
933 return ret;
934}
935
936static void user_recover_prep(void *arg)
937{
938}
939
940static void user_recover_slot(void *arg, struct dlm_slot *slot)
941{
942 struct ocfs2_cluster_connection *conn = arg;
943 printk(KERN_INFO "ocfs2: Node %d/%d down. Initiating recovery.\n",
944 slot->nodeid, slot->slot);
945 conn->cc_recovery_handler(slot->nodeid, conn->cc_recovery_data);
946
947}
948
949static void user_recover_done(void *arg, struct dlm_slot *slots,
950 int num_slots, int our_slot,
951 uint32_t generation)
952{
953 struct ocfs2_cluster_connection *conn = arg;
954 struct ocfs2_live_connection *lc = conn->cc_private;
955 int i;
956
957 for (i = 0; i < num_slots; i++)
958 if (slots[i].slot == our_slot) {
959 atomic_set(&lc->oc_this_node, slots[i].nodeid);
960 break;
961 }
962
963 lc->oc_our_slot = our_slot;
964 wake_up(&lc->oc_wait);
965}
966
967static const struct dlm_lockspace_ops ocfs2_ls_ops = {
968 .recover_prep = user_recover_prep,
969 .recover_slot = user_recover_slot,
970 .recover_done = user_recover_done,
971};
972
973static int user_cluster_disconnect(struct ocfs2_cluster_connection *conn)
974{
975 version_unlock(conn);
976 dlm_release_lockspace(conn->cc_lockspace, 2);
977 conn->cc_lockspace = NULL;
978 ocfs2_live_connection_drop(conn->cc_private);
979 conn->cc_private = NULL;
980 return 0;
981}
982
983static int user_cluster_connect(struct ocfs2_cluster_connection *conn)
984{
985 dlm_lockspace_t *fsdlm;
986 struct ocfs2_live_connection *lc;
987 int rc, ops_rv;
988
989 BUG_ON(conn == NULL);
990
991 lc = kzalloc(sizeof(struct ocfs2_live_connection), GFP_KERNEL);
992 if (!lc)
993 return -ENOMEM;
994
995 init_waitqueue_head(&lc->oc_wait);
996 init_completion(&lc->oc_sync_wait);
997 atomic_set(&lc->oc_this_node, 0);
998 conn->cc_private = lc;
999 lc->oc_type = NO_CONTROLD;
1000
1001 rc = dlm_new_lockspace(conn->cc_name, conn->cc_cluster_name,
1002 DLM_LSFL_FS | DLM_LSFL_NEWEXCL, DLM_LVB_LEN,
1003 &ocfs2_ls_ops, conn, &ops_rv, &fsdlm);
1004 if (rc) {
1005 if (rc == -EEXIST || rc == -EPROTO)
1006 printk(KERN_ERR "ocfs2: Unable to create the "
1007 "lockspace %s (%d), because a ocfs2-tools "
1008 "program is running on this file system "
1009 "with the same name lockspace\n",
1010 conn->cc_name, rc);
1011 goto out;
1012 }
1013
1014 if (ops_rv == -EOPNOTSUPP) {
1015 lc->oc_type = WITH_CONTROLD;
1016 printk(KERN_NOTICE "ocfs2: You seem to be using an older "
1017 "version of dlm_controld and/or ocfs2-tools."
1018 " Please consider upgrading.\n");
1019 } else if (ops_rv) {
1020 rc = ops_rv;
1021 goto out;
1022 }
1023 conn->cc_lockspace = fsdlm;
1024
1025 rc = ocfs2_live_connection_attach(conn, lc);
1026 if (rc)
1027 goto out;
1028
1029 if (lc->oc_type == NO_CONTROLD) {
1030 rc = get_protocol_version(conn);
1031 if (rc) {
1032 printk(KERN_ERR "ocfs2: Could not determine"
1033 " locking version\n");
1034 user_cluster_disconnect(conn);
1035 goto out;
1036 }
1037 wait_event(lc->oc_wait, (atomic_read(&lc->oc_this_node) > 0));
1038 }
1039
1040 /*
1041 * running_proto must have been set before we allowed any mounts
1042 * to proceed.
1043 */
1044 if (fs_protocol_compare(&running_proto, &conn->cc_version)) {
1045 printk(KERN_ERR
1046 "Unable to mount with fs locking protocol version "
1047 "%u.%u because negotiated protocol is %u.%u\n",
1048 conn->cc_version.pv_major, conn->cc_version.pv_minor,
1049 running_proto.pv_major, running_proto.pv_minor);
1050 rc = -EPROTO;
1051 ocfs2_live_connection_drop(lc);
1052 lc = NULL;
1053 }
1054
1055out:
1056 if (rc)
1057 kfree(lc);
1058 return rc;
1059}
1060
1061
1062static int user_cluster_this_node(struct ocfs2_cluster_connection *conn,
1063 unsigned int *this_node)
1064{
1065 int rc;
1066 struct ocfs2_live_connection *lc = conn->cc_private;
1067
1068 if (lc->oc_type == WITH_CONTROLD)
1069 rc = ocfs2_control_get_this_node();
1070 else if (lc->oc_type == NO_CONTROLD)
1071 rc = atomic_read(&lc->oc_this_node);
1072 else
1073 rc = -EINVAL;
1074
1075 if (rc < 0)
1076 return rc;
1077
1078 *this_node = rc;
1079 return 0;
1080}
1081
1082static struct ocfs2_stack_operations ocfs2_user_plugin_ops = {
1083 .connect = user_cluster_connect,
1084 .disconnect = user_cluster_disconnect,
1085 .this_node = user_cluster_this_node,
1086 .dlm_lock = user_dlm_lock,
1087 .dlm_unlock = user_dlm_unlock,
1088 .lock_status = user_dlm_lock_status,
1089 .lvb_valid = user_dlm_lvb_valid,
1090 .lock_lvb = user_dlm_lvb,
1091 .plock = user_plock,
1092 .dump_lksb = user_dlm_dump_lksb,
1093};
1094
1095static struct ocfs2_stack_plugin ocfs2_user_plugin = {
1096 .sp_name = "user",
1097 .sp_ops = &ocfs2_user_plugin_ops,
1098 .sp_owner = THIS_MODULE,
1099};
1100
1101
1102static int __init ocfs2_user_plugin_init(void)
1103{
1104 int rc;
1105
1106 rc = ocfs2_control_init();
1107 if (!rc) {
1108 rc = ocfs2_stack_glue_register(&ocfs2_user_plugin);
1109 if (rc)
1110 ocfs2_control_exit();
1111 }
1112
1113 return rc;
1114}
1115
1116static void __exit ocfs2_user_plugin_exit(void)
1117{
1118 ocfs2_stack_glue_unregister(&ocfs2_user_plugin);
1119 ocfs2_control_exit();
1120}
1121
1122MODULE_AUTHOR("Oracle");
1123MODULE_DESCRIPTION("ocfs2 driver for userspace cluster stacks");
1124MODULE_LICENSE("GPL");
1125module_init(ocfs2_user_plugin_init);
1126module_exit(ocfs2_user_plugin_exit);