blob: e96bf3e9be88e566e1095f6960974a5e3fc1340d [file] [log] [blame]
David Teigland597d0ca2006-07-12 16:44:04 -05001/*
David Teigland7fe2b312010-02-24 11:08:18 -06002 * Copyright (C) 2006-2010 Red Hat, Inc. All rights reserved.
David Teigland597d0ca2006-07-12 16:44:04 -05003 *
4 * This copyrighted material is made available to anyone wishing to use,
5 * modify, copy, or redistribute it subject to the terms and conditions
6 * of the GNU General Public License v.2.
7 */
8
9#include <linux/miscdevice.h>
10#include <linux/init.h>
11#include <linux/wait.h>
12#include <linux/module.h>
13#include <linux/file.h>
14#include <linux/fs.h>
15#include <linux/poll.h>
16#include <linux/signal.h>
17#include <linux/spinlock.h>
18#include <linux/dlm.h>
19#include <linux/dlm_device.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090020#include <linux/slab.h>
David Teigland597d0ca2006-07-12 16:44:04 -050021
22#include "dlm_internal.h"
23#include "lockspace.h"
24#include "lock.h"
25#include "lvb_table.h"
Adrian Bunk84c6e8c2007-02-26 00:18:42 +010026#include "user.h"
David Teigland8304d6f2011-02-21 14:58:21 -060027#include "ast.h"
David Teigland597d0ca2006-07-12 16:44:04 -050028
Denis Cheng0fe410d2008-01-29 13:50:16 +080029static const char name_prefix[] = "dlm";
Arjan van de Ven00977a52007-02-12 00:55:34 -080030static const struct file_operations device_fops;
David Teiglanddc68c7e2008-08-18 11:43:30 -050031static atomic_t dlm_monitor_opened;
32static int dlm_monitor_unused = 1;
David Teigland597d0ca2006-07-12 16:44:04 -050033
34#ifdef CONFIG_COMPAT
35
36struct dlm_lock_params32 {
37 __u8 mode;
38 __u8 namelen;
David Teiglandd7db9232007-05-18 09:00:32 -050039 __u16 unused;
40 __u32 flags;
David Teigland597d0ca2006-07-12 16:44:04 -050041 __u32 lkid;
42 __u32 parent;
David Teiglandd7db9232007-05-18 09:00:32 -050043 __u64 xid;
44 __u64 timeout;
David Teigland597d0ca2006-07-12 16:44:04 -050045 __u32 castparam;
46 __u32 castaddr;
47 __u32 bastparam;
48 __u32 bastaddr;
49 __u32 lksb;
David Teigland597d0ca2006-07-12 16:44:04 -050050 char lvb[DLM_USER_LVB_LEN];
51 char name[0];
52};
53
54struct dlm_write_request32 {
55 __u32 version[3];
56 __u8 cmd;
57 __u8 is64bit;
58 __u8 unused[2];
59
60 union {
61 struct dlm_lock_params32 lock;
62 struct dlm_lspace_params lspace;
David Teigland72c2be72007-03-30 15:06:16 -050063 struct dlm_purge_params purge;
David Teigland597d0ca2006-07-12 16:44:04 -050064 } i;
65};
66
67struct dlm_lksb32 {
68 __u32 sb_status;
69 __u32 sb_lkid;
70 __u8 sb_flags;
71 __u32 sb_lvbptr;
72};
73
74struct dlm_lock_result32 {
David Teiglandd7db9232007-05-18 09:00:32 -050075 __u32 version[3];
David Teigland597d0ca2006-07-12 16:44:04 -050076 __u32 length;
77 __u32 user_astaddr;
78 __u32 user_astparam;
79 __u32 user_lksb;
80 struct dlm_lksb32 lksb;
81 __u8 bast_mode;
82 __u8 unused[3];
83 /* Offsets may be zero if no data is present */
84 __u32 lvb_offset;
85};
86
87static void compat_input(struct dlm_write_request *kb,
Patrick Caulfeld2a792892008-01-17 10:25:28 +000088 struct dlm_write_request32 *kb32,
David Teigland1fecb1c2009-03-04 11:17:23 -060089 int namelen)
David Teigland597d0ca2006-07-12 16:44:04 -050090{
91 kb->version[0] = kb32->version[0];
92 kb->version[1] = kb32->version[1];
93 kb->version[2] = kb32->version[2];
94
95 kb->cmd = kb32->cmd;
96 kb->is64bit = kb32->is64bit;
97 if (kb->cmd == DLM_USER_CREATE_LOCKSPACE ||
98 kb->cmd == DLM_USER_REMOVE_LOCKSPACE) {
99 kb->i.lspace.flags = kb32->i.lspace.flags;
100 kb->i.lspace.minor = kb32->i.lspace.minor;
David Teigland1fecb1c2009-03-04 11:17:23 -0600101 memcpy(kb->i.lspace.name, kb32->i.lspace.name, namelen);
David Teigland72c2be72007-03-30 15:06:16 -0500102 } else if (kb->cmd == DLM_USER_PURGE) {
103 kb->i.purge.nodeid = kb32->i.purge.nodeid;
104 kb->i.purge.pid = kb32->i.purge.pid;
David Teigland597d0ca2006-07-12 16:44:04 -0500105 } else {
106 kb->i.lock.mode = kb32->i.lock.mode;
107 kb->i.lock.namelen = kb32->i.lock.namelen;
108 kb->i.lock.flags = kb32->i.lock.flags;
109 kb->i.lock.lkid = kb32->i.lock.lkid;
110 kb->i.lock.parent = kb32->i.lock.parent;
David Teiglandd7db9232007-05-18 09:00:32 -0500111 kb->i.lock.xid = kb32->i.lock.xid;
112 kb->i.lock.timeout = kb32->i.lock.timeout;
David Teigland597d0ca2006-07-12 16:44:04 -0500113 kb->i.lock.castparam = (void *)(long)kb32->i.lock.castparam;
114 kb->i.lock.castaddr = (void *)(long)kb32->i.lock.castaddr;
115 kb->i.lock.bastparam = (void *)(long)kb32->i.lock.bastparam;
116 kb->i.lock.bastaddr = (void *)(long)kb32->i.lock.bastaddr;
117 kb->i.lock.lksb = (void *)(long)kb32->i.lock.lksb;
118 memcpy(kb->i.lock.lvb, kb32->i.lock.lvb, DLM_USER_LVB_LEN);
David Teigland1fecb1c2009-03-04 11:17:23 -0600119 memcpy(kb->i.lock.name, kb32->i.lock.name, namelen);
David Teigland597d0ca2006-07-12 16:44:04 -0500120 }
121}
122
123static void compat_output(struct dlm_lock_result *res,
124 struct dlm_lock_result32 *res32)
125{
David Teiglandd7db9232007-05-18 09:00:32 -0500126 res32->version[0] = res->version[0];
127 res32->version[1] = res->version[1];
128 res32->version[2] = res->version[2];
129
David Teigland597d0ca2006-07-12 16:44:04 -0500130 res32->user_astaddr = (__u32)(long)res->user_astaddr;
131 res32->user_astparam = (__u32)(long)res->user_astparam;
132 res32->user_lksb = (__u32)(long)res->user_lksb;
133 res32->bast_mode = res->bast_mode;
134
135 res32->lvb_offset = res->lvb_offset;
136 res32->length = res->length;
137
138 res32->lksb.sb_status = res->lksb.sb_status;
139 res32->lksb.sb_flags = res->lksb.sb_flags;
140 res32->lksb.sb_lkid = res->lksb.sb_lkid;
141 res32->lksb.sb_lvbptr = (__u32)(long)res->lksb.sb_lvbptr;
142}
143#endif
144
David Teigland84d8cd62007-05-29 08:44:23 -0500145/* Figure out if this lock is at the end of its life and no longer
146 available for the application to use. The lkb still exists until
147 the final ast is read. A lock becomes EOL in three situations:
148 1. a noqueue request fails with EAGAIN
149 2. an unlock completes with EUNLOCK
150 3. a cancel of a waiting request completes with ECANCEL/EDEADLK
151 An EOL lock needs to be removed from the process's list of locks.
152 And we can't allow any new operation on an EOL lock. This is
153 not related to the lifetime of the lkb struct which is managed
154 entirely by refcount. */
155
David Teigland8304d6f2011-02-21 14:58:21 -0600156static int lkb_is_endoflife(int mode, int status)
David Teigland84d8cd62007-05-29 08:44:23 -0500157{
David Teigland8304d6f2011-02-21 14:58:21 -0600158 switch (status) {
David Teigland84d8cd62007-05-29 08:44:23 -0500159 case -DLM_EUNLOCK:
160 return 1;
161 case -DLM_ECANCEL:
162 case -ETIMEDOUT:
David Teigland8b4021f2007-05-29 08:46:00 -0500163 case -EDEADLK:
David Teigland84d8cd62007-05-29 08:44:23 -0500164 case -EAGAIN:
David Teigland8304d6f2011-02-21 14:58:21 -0600165 if (mode == DLM_LOCK_IV)
David Teigland84d8cd62007-05-29 08:44:23 -0500166 return 1;
167 break;
168 }
169 return 0;
170}
171
David Teiglandef0c2bb2007-03-28 09:56:46 -0500172/* we could possibly check if the cancel of an orphan has resulted in the lkb
173 being removed and then remove that lkb from the orphans list and free it */
David Teigland597d0ca2006-07-12 16:44:04 -0500174
David Teigland8304d6f2011-02-21 14:58:21 -0600175void dlm_user_add_ast(struct dlm_lkb *lkb, uint32_t flags, int mode,
176 int status, uint32_t sbflags, uint64_t seq)
David Teigland597d0ca2006-07-12 16:44:04 -0500177{
178 struct dlm_ls *ls;
179 struct dlm_user_args *ua;
180 struct dlm_user_proc *proc;
David Teigland8304d6f2011-02-21 14:58:21 -0600181 int rv;
David Teigland597d0ca2006-07-12 16:44:04 -0500182
David Teiglandef0c2bb2007-03-28 09:56:46 -0500183 if (lkb->lkb_flags & (DLM_IFL_ORPHAN | DLM_IFL_DEAD))
David Teigland597d0ca2006-07-12 16:44:04 -0500184 return;
David Teigland597d0ca2006-07-12 16:44:04 -0500185
186 ls = lkb->lkb_resource->res_ls;
187 mutex_lock(&ls->ls_clear_proc_locks);
188
189 /* If ORPHAN/DEAD flag is set, it means the process is dead so an ast
190 can't be delivered. For ORPHAN's, dlm_clear_proc_locks() freed
David Teiglandef0c2bb2007-03-28 09:56:46 -0500191 lkb->ua so we can't try to use it. This second check is necessary
192 for cases where a completion ast is received for an operation that
193 began before clear_proc_locks did its cancel/unlock. */
David Teigland597d0ca2006-07-12 16:44:04 -0500194
David Teiglandef0c2bb2007-03-28 09:56:46 -0500195 if (lkb->lkb_flags & (DLM_IFL_ORPHAN | DLM_IFL_DEAD))
David Teigland597d0ca2006-07-12 16:44:04 -0500196 goto out;
David Teigland597d0ca2006-07-12 16:44:04 -0500197
David Teiglandd292c0c2008-02-06 23:27:04 -0600198 DLM_ASSERT(lkb->lkb_ua, dlm_print_lkb(lkb););
199 ua = lkb->lkb_ua;
David Teigland597d0ca2006-07-12 16:44:04 -0500200 proc = ua->proc;
201
David Teigland8304d6f2011-02-21 14:58:21 -0600202 if ((flags & DLM_CB_BAST) && ua->bastaddr == NULL)
David Teigland597d0ca2006-07-12 16:44:04 -0500203 goto out;
204
David Teigland8304d6f2011-02-21 14:58:21 -0600205 if ((flags & DLM_CB_CAST) && lkb_is_endoflife(mode, status))
206 lkb->lkb_flags |= DLM_IFL_ENDOFLIFE;
207
David Teigland597d0ca2006-07-12 16:44:04 -0500208 spin_lock(&proc->asts_spin);
David Teiglandef0c2bb2007-03-28 09:56:46 -0500209
David Teigland8304d6f2011-02-21 14:58:21 -0600210 rv = dlm_add_lkb_callback(lkb, flags, mode, status, sbflags, seq);
211 if (rv < 0) {
212 spin_unlock(&proc->asts_spin);
213 goto out;
214 }
David Teiglandef0c2bb2007-03-28 09:56:46 -0500215
David Teigland8304d6f2011-02-21 14:58:21 -0600216 if (list_empty(&lkb->lkb_astqueue)) {
David Teigland597d0ca2006-07-12 16:44:04 -0500217 kref_get(&lkb->lkb_ref);
218 list_add_tail(&lkb->lkb_astqueue, &proc->asts);
David Teigland597d0ca2006-07-12 16:44:04 -0500219 wake_up_interruptible(&proc->wait);
220 }
David Teigland597d0ca2006-07-12 16:44:04 -0500221 spin_unlock(&proc->asts_spin);
David Teigland34e22be2006-07-18 11:24:04 -0500222
David Teigland8304d6f2011-02-21 14:58:21 -0600223 if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
224 /* N.B. spin_lock locks_spin, not asts_spin */
David Teiglandce5246b2008-01-14 15:48:58 -0600225 spin_lock(&proc->locks_spin);
David Teiglandef0c2bb2007-03-28 09:56:46 -0500226 if (!list_empty(&lkb->lkb_ownqueue)) {
227 list_del_init(&lkb->lkb_ownqueue);
228 dlm_put_lkb(lkb);
229 }
David Teiglandce5246b2008-01-14 15:48:58 -0600230 spin_unlock(&proc->locks_spin);
David Teigland34e22be2006-07-18 11:24:04 -0500231 }
David Teigland597d0ca2006-07-12 16:44:04 -0500232 out:
233 mutex_unlock(&ls->ls_clear_proc_locks);
234}
235
236static int device_user_lock(struct dlm_user_proc *proc,
237 struct dlm_lock_params *params)
238{
239 struct dlm_ls *ls;
240 struct dlm_user_args *ua;
241 int error = -ENOMEM;
242
243 ls = dlm_find_lockspace_local(proc->lockspace);
244 if (!ls)
245 return -ENOENT;
246
247 if (!params->castaddr || !params->lksb) {
248 error = -EINVAL;
249 goto out;
250 }
251
David Teigland573c24c2009-11-30 16:34:43 -0600252 ua = kzalloc(sizeof(struct dlm_user_args), GFP_NOFS);
David Teigland597d0ca2006-07-12 16:44:04 -0500253 if (!ua)
254 goto out;
255 ua->proc = proc;
256 ua->user_lksb = params->lksb;
257 ua->castparam = params->castparam;
258 ua->castaddr = params->castaddr;
259 ua->bastparam = params->bastparam;
260 ua->bastaddr = params->bastaddr;
David Teiglandd7db9232007-05-18 09:00:32 -0500261 ua->xid = params->xid;
David Teigland597d0ca2006-07-12 16:44:04 -0500262
263 if (params->flags & DLM_LKF_CONVERT)
264 error = dlm_user_convert(ls, ua,
265 params->mode, params->flags,
David Teiglandd7db9232007-05-18 09:00:32 -0500266 params->lkid, params->lvb,
267 (unsigned long) params->timeout);
David Teigland597d0ca2006-07-12 16:44:04 -0500268 else {
269 error = dlm_user_request(ls, ua,
270 params->mode, params->flags,
271 params->name, params->namelen,
David Teiglandd7db9232007-05-18 09:00:32 -0500272 (unsigned long) params->timeout);
David Teigland597d0ca2006-07-12 16:44:04 -0500273 if (!error)
274 error = ua->lksb.sb_lkid;
275 }
276 out:
277 dlm_put_lockspace(ls);
278 return error;
279}
280
281static int device_user_unlock(struct dlm_user_proc *proc,
282 struct dlm_lock_params *params)
283{
284 struct dlm_ls *ls;
285 struct dlm_user_args *ua;
286 int error = -ENOMEM;
287
288 ls = dlm_find_lockspace_local(proc->lockspace);
289 if (!ls)
290 return -ENOENT;
291
David Teigland573c24c2009-11-30 16:34:43 -0600292 ua = kzalloc(sizeof(struct dlm_user_args), GFP_NOFS);
David Teigland597d0ca2006-07-12 16:44:04 -0500293 if (!ua)
294 goto out;
295 ua->proc = proc;
296 ua->user_lksb = params->lksb;
297 ua->castparam = params->castparam;
298 ua->castaddr = params->castaddr;
299
300 if (params->flags & DLM_LKF_CANCEL)
301 error = dlm_user_cancel(ls, ua, params->flags, params->lkid);
302 else
303 error = dlm_user_unlock(ls, ua, params->flags, params->lkid,
304 params->lvb);
305 out:
306 dlm_put_lockspace(ls);
307 return error;
308}
309
David Teigland8b4021f2007-05-29 08:46:00 -0500310static int device_user_deadlock(struct dlm_user_proc *proc,
311 struct dlm_lock_params *params)
312{
313 struct dlm_ls *ls;
314 int error;
315
316 ls = dlm_find_lockspace_local(proc->lockspace);
317 if (!ls)
318 return -ENOENT;
319
320 error = dlm_user_deadlock(ls, params->flags, params->lkid);
321
322 dlm_put_lockspace(ls);
323 return error;
324}
325
David Teigland0f8e0d92008-08-06 13:30:24 -0500326static int dlm_device_register(struct dlm_ls *ls, char *name)
Patrick Caulfield254da032007-03-21 09:23:53 +0000327{
328 int error, len;
329
David Teigland0f8e0d92008-08-06 13:30:24 -0500330 /* The device is already registered. This happens when the
331 lockspace is created multiple times from userspace. */
332 if (ls->ls_device.name)
333 return 0;
334
Patrick Caulfield254da032007-03-21 09:23:53 +0000335 error = -ENOMEM;
336 len = strlen(name) + strlen(name_prefix) + 2;
David Teigland573c24c2009-11-30 16:34:43 -0600337 ls->ls_device.name = kzalloc(len, GFP_NOFS);
Patrick Caulfield254da032007-03-21 09:23:53 +0000338 if (!ls->ls_device.name)
339 goto fail;
340
341 snprintf((char *)ls->ls_device.name, len, "%s_%s", name_prefix,
342 name);
343 ls->ls_device.fops = &device_fops;
344 ls->ls_device.minor = MISC_DYNAMIC_MINOR;
345
346 error = misc_register(&ls->ls_device);
347 if (error) {
348 kfree(ls->ls_device.name);
349 }
350fail:
351 return error;
352}
353
David Teigland0f8e0d92008-08-06 13:30:24 -0500354int dlm_device_deregister(struct dlm_ls *ls)
355{
356 int error;
357
358 /* The device is not registered. This happens when the lockspace
359 was never used from userspace, or when device_create_lockspace()
360 calls dlm_release_lockspace() after the register fails. */
361 if (!ls->ls_device.name)
362 return 0;
363
364 error = misc_deregister(&ls->ls_device);
365 if (!error)
366 kfree(ls->ls_device.name);
367 return error;
368}
369
David Teigland72c2be72007-03-30 15:06:16 -0500370static int device_user_purge(struct dlm_user_proc *proc,
371 struct dlm_purge_params *params)
372{
373 struct dlm_ls *ls;
374 int error;
375
376 ls = dlm_find_lockspace_local(proc->lockspace);
377 if (!ls)
378 return -ENOENT;
379
380 error = dlm_user_purge(ls, proc, params->nodeid, params->pid);
381
382 dlm_put_lockspace(ls);
383 return error;
384}
385
David Teigland597d0ca2006-07-12 16:44:04 -0500386static int device_create_lockspace(struct dlm_lspace_params *params)
387{
388 dlm_lockspace_t *lockspace;
389 struct dlm_ls *ls;
Patrick Caulfield254da032007-03-21 09:23:53 +0000390 int error;
David Teigland597d0ca2006-07-12 16:44:04 -0500391
392 if (!capable(CAP_SYS_ADMIN))
393 return -EPERM;
394
395 error = dlm_new_lockspace(params->name, strlen(params->name),
David Teigland3ae1acf2007-05-18 08:59:31 -0500396 &lockspace, params->flags, DLM_USER_LVB_LEN);
David Teigland597d0ca2006-07-12 16:44:04 -0500397 if (error)
398 return error;
399
400 ls = dlm_find_lockspace_local(lockspace);
401 if (!ls)
402 return -ENOENT;
403
David Teigland0f8e0d92008-08-06 13:30:24 -0500404 error = dlm_device_register(ls, params->name);
David Teigland597d0ca2006-07-12 16:44:04 -0500405 dlm_put_lockspace(ls);
David Teigland597d0ca2006-07-12 16:44:04 -0500406
Patrick Caulfield254da032007-03-21 09:23:53 +0000407 if (error)
408 dlm_release_lockspace(lockspace, 0);
409 else
410 error = ls->ls_device.minor;
411
David Teigland597d0ca2006-07-12 16:44:04 -0500412 return error;
413}
414
415static int device_remove_lockspace(struct dlm_lspace_params *params)
416{
417 dlm_lockspace_t *lockspace;
418 struct dlm_ls *ls;
David Teiglandc6e6f0b2006-08-30 10:50:18 -0500419 int error, force = 0;
David Teigland597d0ca2006-07-12 16:44:04 -0500420
421 if (!capable(CAP_SYS_ADMIN))
422 return -EPERM;
423
424 ls = dlm_find_lockspace_device(params->minor);
425 if (!ls)
426 return -ENOENT;
427
David Teiglandc6e6f0b2006-08-30 10:50:18 -0500428 if (params->flags & DLM_USER_LSFLG_FORCEFREE)
429 force = 2;
430
David Teigland597d0ca2006-07-12 16:44:04 -0500431 lockspace = ls->ls_local_handle;
David Teigland597d0ca2006-07-12 16:44:04 -0500432 dlm_put_lockspace(ls);
David Teigland0f8e0d92008-08-06 13:30:24 -0500433
434 /* The final dlm_release_lockspace waits for references to go to
435 zero, so all processes will need to close their device for the
436 ls before the release will proceed. release also calls the
437 device_deregister above. Converting a positive return value
438 from release to zero means that userspace won't know when its
439 release was the final one, but it shouldn't need to know. */
440
David Teiglandc6e6f0b2006-08-30 10:50:18 -0500441 error = dlm_release_lockspace(lockspace, force);
David Teigland0f8e0d92008-08-06 13:30:24 -0500442 if (error > 0)
443 error = 0;
David Teigland597d0ca2006-07-12 16:44:04 -0500444 return error;
445}
446
447/* Check the user's version matches ours */
448static int check_version(struct dlm_write_request *req)
449{
450 if (req->version[0] != DLM_DEVICE_VERSION_MAJOR ||
451 (req->version[0] == DLM_DEVICE_VERSION_MAJOR &&
452 req->version[1] > DLM_DEVICE_VERSION_MINOR)) {
453
454 printk(KERN_DEBUG "dlm: process %s (%d) version mismatch "
455 "user (%d.%d.%d) kernel (%d.%d.%d)\n",
456 current->comm,
Pavel Emelyanovba25f9d2007-10-18 23:40:40 -0700457 task_pid_nr(current),
David Teigland597d0ca2006-07-12 16:44:04 -0500458 req->version[0],
459 req->version[1],
460 req->version[2],
461 DLM_DEVICE_VERSION_MAJOR,
462 DLM_DEVICE_VERSION_MINOR,
463 DLM_DEVICE_VERSION_PATCH);
464 return -EINVAL;
465 }
466 return 0;
467}
468
469/*
470 * device_write
471 *
472 * device_user_lock
473 * dlm_user_request -> request_lock
474 * dlm_user_convert -> convert_lock
475 *
476 * device_user_unlock
477 * dlm_user_unlock -> unlock_lock
478 * dlm_user_cancel -> cancel_lock
479 *
480 * device_create_lockspace
481 * dlm_new_lockspace
482 *
483 * device_remove_lockspace
484 * dlm_release_lockspace
485 */
486
487/* a write to a lockspace device is a lock or unlock request, a write
488 to the control device is to create/remove a lockspace */
489
490static ssize_t device_write(struct file *file, const char __user *buf,
491 size_t count, loff_t *ppos)
492{
493 struct dlm_user_proc *proc = file->private_data;
494 struct dlm_write_request *kbuf;
495 sigset_t tmpsig, allsigs;
496 int error;
497
498#ifdef CONFIG_COMPAT
499 if (count < sizeof(struct dlm_write_request32))
500#else
501 if (count < sizeof(struct dlm_write_request))
502#endif
503 return -EINVAL;
504
David Teigland573c24c2009-11-30 16:34:43 -0600505 kbuf = kzalloc(count + 1, GFP_NOFS);
David Teigland597d0ca2006-07-12 16:44:04 -0500506 if (!kbuf)
507 return -ENOMEM;
508
509 if (copy_from_user(kbuf, buf, count)) {
510 error = -EFAULT;
511 goto out_free;
512 }
513
514 if (check_version(kbuf)) {
515 error = -EBADE;
516 goto out_free;
517 }
518
519#ifdef CONFIG_COMPAT
520 if (!kbuf->is64bit) {
521 struct dlm_write_request32 *k32buf;
David Teigland1fecb1c2009-03-04 11:17:23 -0600522 int namelen = 0;
523
524 if (count > sizeof(struct dlm_write_request32))
525 namelen = count - sizeof(struct dlm_write_request32);
526
David Teigland597d0ca2006-07-12 16:44:04 -0500527 k32buf = (struct dlm_write_request32 *)kbuf;
David Teigland1fecb1c2009-03-04 11:17:23 -0600528
529 /* add 1 after namelen so that the name string is terminated */
530 kbuf = kzalloc(sizeof(struct dlm_write_request) + namelen + 1,
David Teigland573c24c2009-11-30 16:34:43 -0600531 GFP_NOFS);
David Teiglandcb980d92008-07-29 15:21:19 -0500532 if (!kbuf) {
533 kfree(k32buf);
David Teigland597d0ca2006-07-12 16:44:04 -0500534 return -ENOMEM;
David Teiglandcb980d92008-07-29 15:21:19 -0500535 }
David Teigland597d0ca2006-07-12 16:44:04 -0500536
537 if (proc)
538 set_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags);
David Teigland1fecb1c2009-03-04 11:17:23 -0600539
540 compat_input(kbuf, k32buf, namelen);
David Teigland597d0ca2006-07-12 16:44:04 -0500541 kfree(k32buf);
542 }
543#endif
544
545 /* do we really need this? can a write happen after a close? */
546 if ((kbuf->cmd == DLM_USER_LOCK || kbuf->cmd == DLM_USER_UNLOCK) &&
David Teiglandcb980d92008-07-29 15:21:19 -0500547 (proc && test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags))) {
548 error = -EINVAL;
549 goto out_free;
550 }
David Teigland597d0ca2006-07-12 16:44:04 -0500551
552 sigfillset(&allsigs);
553 sigprocmask(SIG_BLOCK, &allsigs, &tmpsig);
554
555 error = -EINVAL;
556
557 switch (kbuf->cmd)
558 {
559 case DLM_USER_LOCK:
560 if (!proc) {
561 log_print("no locking on control device");
562 goto out_sig;
563 }
564 error = device_user_lock(proc, &kbuf->i.lock);
565 break;
566
567 case DLM_USER_UNLOCK:
568 if (!proc) {
569 log_print("no locking on control device");
570 goto out_sig;
571 }
572 error = device_user_unlock(proc, &kbuf->i.lock);
573 break;
574
David Teigland8b4021f2007-05-29 08:46:00 -0500575 case DLM_USER_DEADLOCK:
576 if (!proc) {
577 log_print("no locking on control device");
578 goto out_sig;
579 }
580 error = device_user_deadlock(proc, &kbuf->i.lock);
581 break;
582
David Teigland597d0ca2006-07-12 16:44:04 -0500583 case DLM_USER_CREATE_LOCKSPACE:
584 if (proc) {
585 log_print("create/remove only on control device");
586 goto out_sig;
587 }
588 error = device_create_lockspace(&kbuf->i.lspace);
589 break;
590
591 case DLM_USER_REMOVE_LOCKSPACE:
592 if (proc) {
593 log_print("create/remove only on control device");
594 goto out_sig;
595 }
596 error = device_remove_lockspace(&kbuf->i.lspace);
597 break;
598
David Teigland72c2be72007-03-30 15:06:16 -0500599 case DLM_USER_PURGE:
600 if (!proc) {
601 log_print("no locking on control device");
602 goto out_sig;
603 }
604 error = device_user_purge(proc, &kbuf->i.purge);
605 break;
606
David Teigland597d0ca2006-07-12 16:44:04 -0500607 default:
608 log_print("Unknown command passed to DLM device : %d\n",
609 kbuf->cmd);
610 }
611
612 out_sig:
613 sigprocmask(SIG_SETMASK, &tmpsig, NULL);
David Teigland597d0ca2006-07-12 16:44:04 -0500614 out_free:
615 kfree(kbuf);
616 return error;
617}
618
619/* Every process that opens the lockspace device has its own "proc" structure
620 hanging off the open file that's used to keep track of locks owned by the
621 process and asts that need to be delivered to the process. */
622
623static int device_open(struct inode *inode, struct file *file)
624{
625 struct dlm_user_proc *proc;
626 struct dlm_ls *ls;
627
628 ls = dlm_find_lockspace_device(iminor(inode));
David Teiglandf9f2ed42008-09-04 12:51:20 -0500629 if (!ls)
David Teigland597d0ca2006-07-12 16:44:04 -0500630 return -ENOENT;
631
David Teigland573c24c2009-11-30 16:34:43 -0600632 proc = kzalloc(sizeof(struct dlm_user_proc), GFP_NOFS);
David Teigland597d0ca2006-07-12 16:44:04 -0500633 if (!proc) {
634 dlm_put_lockspace(ls);
635 return -ENOMEM;
636 }
637
638 proc->lockspace = ls->ls_local_handle;
639 INIT_LIST_HEAD(&proc->asts);
640 INIT_LIST_HEAD(&proc->locks);
David Teiglanda1bc86e2007-01-15 10:34:52 -0600641 INIT_LIST_HEAD(&proc->unlocking);
David Teigland597d0ca2006-07-12 16:44:04 -0500642 spin_lock_init(&proc->asts_spin);
643 spin_lock_init(&proc->locks_spin);
644 init_waitqueue_head(&proc->wait);
645 file->private_data = proc;
646
647 return 0;
648}
649
650static int device_close(struct inode *inode, struct file *file)
651{
652 struct dlm_user_proc *proc = file->private_data;
653 struct dlm_ls *ls;
654 sigset_t tmpsig, allsigs;
655
656 ls = dlm_find_lockspace_local(proc->lockspace);
657 if (!ls)
658 return -ENOENT;
659
660 sigfillset(&allsigs);
661 sigprocmask(SIG_BLOCK, &allsigs, &tmpsig);
662
663 set_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags);
664
665 dlm_clear_proc_locks(ls, proc);
666
667 /* at this point no more lkb's should exist for this lockspace,
668 so there's no chance of dlm_user_add_ast() being called and
669 looking for lkb->ua->proc */
670
671 kfree(proc);
672 file->private_data = NULL;
673
674 dlm_put_lockspace(ls);
675 dlm_put_lockspace(ls); /* for the find in device_open() */
676
677 /* FIXME: AUTOFREE: if this ls is no longer used do
678 device_remove_lockspace() */
679
680 sigprocmask(SIG_SETMASK, &tmpsig, NULL);
681 recalc_sigpending();
682
683 return 0;
684}
685
David Teigland8304d6f2011-02-21 14:58:21 -0600686static int copy_result_to_user(struct dlm_user_args *ua, int compat,
687 uint32_t flags, int mode, int copy_lvb,
688 char __user *buf, size_t count)
David Teigland597d0ca2006-07-12 16:44:04 -0500689{
690#ifdef CONFIG_COMPAT
691 struct dlm_lock_result32 result32;
692#endif
693 struct dlm_lock_result result;
694 void *resultptr;
695 int error=0;
696 int len;
697 int struct_len;
698
699 memset(&result, 0, sizeof(struct dlm_lock_result));
David Teiglandd7db9232007-05-18 09:00:32 -0500700 result.version[0] = DLM_DEVICE_VERSION_MAJOR;
701 result.version[1] = DLM_DEVICE_VERSION_MINOR;
702 result.version[2] = DLM_DEVICE_VERSION_PATCH;
David Teigland597d0ca2006-07-12 16:44:04 -0500703 memcpy(&result.lksb, &ua->lksb, sizeof(struct dlm_lksb));
704 result.user_lksb = ua->user_lksb;
705
706 /* FIXME: dlm1 provides for the user's bastparam/addr to not be updated
707 in a conversion unless the conversion is successful. See code
708 in dlm_user_convert() for updating ua from ua_tmp. OpenVMS, though,
709 notes that a new blocking AST address and parameter are set even if
710 the conversion fails, so maybe we should just do that. */
711
David Teigland8304d6f2011-02-21 14:58:21 -0600712 if (flags & DLM_CB_BAST) {
David Teigland597d0ca2006-07-12 16:44:04 -0500713 result.user_astaddr = ua->bastaddr;
714 result.user_astparam = ua->bastparam;
David Teigland89d799d2010-03-25 14:23:13 -0500715 result.bast_mode = mode;
David Teigland597d0ca2006-07-12 16:44:04 -0500716 } else {
717 result.user_astaddr = ua->castaddr;
718 result.user_astparam = ua->castparam;
719 }
720
721#ifdef CONFIG_COMPAT
722 if (compat)
723 len = sizeof(struct dlm_lock_result32);
724 else
725#endif
726 len = sizeof(struct dlm_lock_result);
727 struct_len = len;
728
729 /* copy lvb to userspace if there is one, it's been updated, and
730 the user buffer has space for it */
731
David Teigland8304d6f2011-02-21 14:58:21 -0600732 if (copy_lvb && ua->lksb.sb_lvbptr && count >= len + DLM_USER_LVB_LEN) {
David Teigland597d0ca2006-07-12 16:44:04 -0500733 if (copy_to_user(buf+len, ua->lksb.sb_lvbptr,
734 DLM_USER_LVB_LEN)) {
735 error = -EFAULT;
736 goto out;
737 }
738
739 result.lvb_offset = len;
740 len += DLM_USER_LVB_LEN;
741 }
742
743 result.length = len;
744 resultptr = &result;
745#ifdef CONFIG_COMPAT
746 if (compat) {
747 compat_output(&result, &result32);
748 resultptr = &result32;
749 }
750#endif
751
752 if (copy_to_user(buf, resultptr, struct_len))
753 error = -EFAULT;
754 else
755 error = len;
756 out:
757 return error;
758}
759
David Teiglandd7db9232007-05-18 09:00:32 -0500760static int copy_version_to_user(char __user *buf, size_t count)
761{
762 struct dlm_device_version ver;
763
764 memset(&ver, 0, sizeof(struct dlm_device_version));
765 ver.version[0] = DLM_DEVICE_VERSION_MAJOR;
766 ver.version[1] = DLM_DEVICE_VERSION_MINOR;
767 ver.version[2] = DLM_DEVICE_VERSION_PATCH;
768
769 if (copy_to_user(buf, &ver, sizeof(struct dlm_device_version)))
770 return -EFAULT;
771 return sizeof(struct dlm_device_version);
772}
773
David Teigland597d0ca2006-07-12 16:44:04 -0500774/* a read returns a single ast described in a struct dlm_lock_result */
775
776static ssize_t device_read(struct file *file, char __user *buf, size_t count,
777 loff_t *ppos)
778{
779 struct dlm_user_proc *proc = file->private_data;
780 struct dlm_lkb *lkb;
David Teigland597d0ca2006-07-12 16:44:04 -0500781 DECLARE_WAITQUEUE(wait, current);
David Teigland8304d6f2011-02-21 14:58:21 -0600782 struct dlm_callback cb;
783 int rv, resid, copy_lvb = 0;
David Teigland597d0ca2006-07-12 16:44:04 -0500784
David Teiglandd7db9232007-05-18 09:00:32 -0500785 if (count == sizeof(struct dlm_device_version)) {
David Teigland8304d6f2011-02-21 14:58:21 -0600786 rv = copy_version_to_user(buf, count);
787 return rv;
David Teiglandd7db9232007-05-18 09:00:32 -0500788 }
789
790 if (!proc) {
791 log_print("non-version read from control device %zu", count);
792 return -EINVAL;
793 }
794
David Teigland597d0ca2006-07-12 16:44:04 -0500795#ifdef CONFIG_COMPAT
796 if (count < sizeof(struct dlm_lock_result32))
797#else
798 if (count < sizeof(struct dlm_lock_result))
799#endif
800 return -EINVAL;
801
David Teigland89d799d2010-03-25 14:23:13 -0500802 try_another:
803
David Teigland597d0ca2006-07-12 16:44:04 -0500804 /* do we really need this? can a read happen after a close? */
805 if (test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags))
806 return -EINVAL;
807
808 spin_lock(&proc->asts_spin);
809 if (list_empty(&proc->asts)) {
810 if (file->f_flags & O_NONBLOCK) {
811 spin_unlock(&proc->asts_spin);
812 return -EAGAIN;
813 }
814
815 add_wait_queue(&proc->wait, &wait);
816
817 repeat:
818 set_current_state(TASK_INTERRUPTIBLE);
819 if (list_empty(&proc->asts) && !signal_pending(current)) {
820 spin_unlock(&proc->asts_spin);
821 schedule();
822 spin_lock(&proc->asts_spin);
823 goto repeat;
824 }
825 set_current_state(TASK_RUNNING);
826 remove_wait_queue(&proc->wait, &wait);
827
828 if (signal_pending(current)) {
829 spin_unlock(&proc->asts_spin);
830 return -ERESTARTSYS;
831 }
832 }
833
David Teigland8304d6f2011-02-21 14:58:21 -0600834 /* if we empty lkb_callbacks, we don't want to unlock the spinlock
835 without removing lkb_astqueue; so empty lkb_astqueue is always
836 consistent with empty lkb_callbacks */
David Teigland597d0ca2006-07-12 16:44:04 -0500837
838 lkb = list_entry(proc->asts.next, struct dlm_lkb, lkb_astqueue);
839
David Teigland8304d6f2011-02-21 14:58:21 -0600840 rv = dlm_rem_lkb_callback(lkb->lkb_resource->res_ls, lkb, &cb, &resid);
841 if (rv < 0) {
842 /* this shouldn't happen; lkb should have been removed from
843 list when resid was zero */
844 log_print("dlm_rem_lkb_callback empty %x", lkb->lkb_id);
845 list_del_init(&lkb->lkb_astqueue);
846 spin_unlock(&proc->asts_spin);
847 /* removes ref for proc->asts, may cause lkb to be freed */
848 dlm_put_lkb(lkb);
849 goto try_another;
David Teigland89d799d2010-03-25 14:23:13 -0500850 }
David Teigland8304d6f2011-02-21 14:58:21 -0600851 if (!resid)
852 list_del_init(&lkb->lkb_astqueue);
David Teigland597d0ca2006-07-12 16:44:04 -0500853 spin_unlock(&proc->asts_spin);
854
David Teigland8304d6f2011-02-21 14:58:21 -0600855 if (cb.flags & DLM_CB_SKIP) {
856 /* removes ref for proc->asts, may cause lkb to be freed */
857 if (!resid)
858 dlm_put_lkb(lkb);
859 goto try_another;
David Teigland89d799d2010-03-25 14:23:13 -0500860 }
David Teigland597d0ca2006-07-12 16:44:04 -0500861
David Teigland8304d6f2011-02-21 14:58:21 -0600862 if (cb.flags & DLM_CB_CAST) {
863 int old_mode, new_mode;
David Teigland89d799d2010-03-25 14:23:13 -0500864
David Teigland8304d6f2011-02-21 14:58:21 -0600865 old_mode = lkb->lkb_last_cast.mode;
866 new_mode = cb.mode;
867
868 if (!cb.sb_status && lkb->lkb_lksb->sb_lvbptr &&
869 dlm_lvb_operations[old_mode + 1][new_mode + 1])
870 copy_lvb = 1;
871
872 lkb->lkb_lksb->sb_status = cb.sb_status;
873 lkb->lkb_lksb->sb_flags = cb.sb_flags;
874 }
875
876 rv = copy_result_to_user(lkb->lkb_ua,
877 test_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags),
878 cb.flags, cb.mode, copy_lvb, buf, count);
879
880 /* removes ref for proc->asts, may cause lkb to be freed */
881 if (!resid)
David Teigland597d0ca2006-07-12 16:44:04 -0500882 dlm_put_lkb(lkb);
883
David Teigland8304d6f2011-02-21 14:58:21 -0600884 return rv;
David Teigland597d0ca2006-07-12 16:44:04 -0500885}
886
887static unsigned int device_poll(struct file *file, poll_table *wait)
888{
889 struct dlm_user_proc *proc = file->private_data;
890
891 poll_wait(file, &proc->wait, wait);
892
893 spin_lock(&proc->asts_spin);
894 if (!list_empty(&proc->asts)) {
895 spin_unlock(&proc->asts_spin);
896 return POLLIN | POLLRDNORM;
897 }
898 spin_unlock(&proc->asts_spin);
899 return 0;
900}
901
David Teiglanddc68c7e2008-08-18 11:43:30 -0500902int dlm_user_daemon_available(void)
903{
904 /* dlm_controld hasn't started (or, has started, but not
905 properly populated configfs) */
906
907 if (!dlm_our_nodeid())
908 return 0;
909
910 /* This is to deal with versions of dlm_controld that don't
911 know about the monitor device. We assume that if the
912 dlm_controld was started (above), but the monitor device
913 was never opened, that it's an old version. dlm_controld
914 should open the monitor device before populating configfs. */
915
916 if (dlm_monitor_unused)
917 return 1;
918
919 return atomic_read(&dlm_monitor_opened) ? 1 : 0;
920}
921
David Teigland597d0ca2006-07-12 16:44:04 -0500922static int ctl_device_open(struct inode *inode, struct file *file)
923{
924 file->private_data = NULL;
925 return 0;
926}
927
928static int ctl_device_close(struct inode *inode, struct file *file)
929{
930 return 0;
931}
932
David Teiglanddc68c7e2008-08-18 11:43:30 -0500933static int monitor_device_open(struct inode *inode, struct file *file)
934{
935 atomic_inc(&dlm_monitor_opened);
936 dlm_monitor_unused = 0;
937 return 0;
938}
939
940static int monitor_device_close(struct inode *inode, struct file *file)
941{
942 if (atomic_dec_and_test(&dlm_monitor_opened))
943 dlm_stop_lockspaces();
944 return 0;
945}
946
Arjan van de Ven00977a52007-02-12 00:55:34 -0800947static const struct file_operations device_fops = {
David Teigland597d0ca2006-07-12 16:44:04 -0500948 .open = device_open,
949 .release = device_close,
950 .read = device_read,
951 .write = device_write,
952 .poll = device_poll,
953 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200954 .llseek = noop_llseek,
David Teigland597d0ca2006-07-12 16:44:04 -0500955};
956
Arjan van de Ven00977a52007-02-12 00:55:34 -0800957static const struct file_operations ctl_device_fops = {
David Teigland597d0ca2006-07-12 16:44:04 -0500958 .open = ctl_device_open,
959 .release = ctl_device_close,
David Teiglandd7db9232007-05-18 09:00:32 -0500960 .read = device_read,
David Teigland597d0ca2006-07-12 16:44:04 -0500961 .write = device_write,
962 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200963 .llseek = noop_llseek,
David Teigland597d0ca2006-07-12 16:44:04 -0500964};
965
Denis Cheng0fe410d2008-01-29 13:50:16 +0800966static struct miscdevice ctl_device = {
967 .name = "dlm-control",
968 .fops = &ctl_device_fops,
969 .minor = MISC_DYNAMIC_MINOR,
970};
971
David Teiglanddc68c7e2008-08-18 11:43:30 -0500972static const struct file_operations monitor_device_fops = {
973 .open = monitor_device_open,
974 .release = monitor_device_close,
975 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200976 .llseek = noop_llseek,
David Teiglanddc68c7e2008-08-18 11:43:30 -0500977};
978
979static struct miscdevice monitor_device = {
980 .name = "dlm-monitor",
981 .fops = &monitor_device_fops,
982 .minor = MISC_DYNAMIC_MINOR,
983};
984
Denis Cheng30727172008-02-02 01:53:46 +0800985int __init dlm_user_init(void)
David Teigland597d0ca2006-07-12 16:44:04 -0500986{
987 int error;
988
David Teiglanddc68c7e2008-08-18 11:43:30 -0500989 atomic_set(&dlm_monitor_opened, 0);
David Teigland597d0ca2006-07-12 16:44:04 -0500990
David Teiglanddc68c7e2008-08-18 11:43:30 -0500991 error = misc_register(&ctl_device);
992 if (error) {
993 log_print("misc_register failed for control device");
994 goto out;
995 }
996
997 error = misc_register(&monitor_device);
998 if (error) {
999 log_print("misc_register failed for monitor device");
1000 misc_deregister(&ctl_device);
1001 }
1002 out:
David Teigland597d0ca2006-07-12 16:44:04 -05001003 return error;
1004}
1005
1006void dlm_user_exit(void)
1007{
1008 misc_deregister(&ctl_device);
David Teiglanddc68c7e2008-08-18 11:43:30 -05001009 misc_deregister(&monitor_device);
David Teigland597d0ca2006-07-12 16:44:04 -05001010}
1011