blob: 911649a47dd5ae5b000bfabb2b73b0c71a95ec52 [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 Teigland23e8e1a2011-04-05 13:16:24 -0500216 if (list_empty(&lkb->lkb_cb_list)) {
David Teigland597d0ca2006-07-12 16:44:04 -0500217 kref_get(&lkb->lkb_ref);
David Teigland23e8e1a2011-04-05 13:16:24 -0500218 list_add_tail(&lkb->lkb_cb_list, &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
David Teigland60f98d12011-11-02 14:30:58 -0500395 error = dlm_new_lockspace(params->name, NULL, params->flags,
396 DLM_USER_LVB_LEN, NULL, NULL, NULL,
397 &lockspace);
David Teigland597d0ca2006-07-12 16:44:04 -0500398 if (error)
399 return error;
400
401 ls = dlm_find_lockspace_local(lockspace);
402 if (!ls)
403 return -ENOENT;
404
David Teigland0f8e0d92008-08-06 13:30:24 -0500405 error = dlm_device_register(ls, params->name);
David Teigland597d0ca2006-07-12 16:44:04 -0500406 dlm_put_lockspace(ls);
David Teigland597d0ca2006-07-12 16:44:04 -0500407
Patrick Caulfield254da032007-03-21 09:23:53 +0000408 if (error)
409 dlm_release_lockspace(lockspace, 0);
410 else
411 error = ls->ls_device.minor;
412
David Teigland597d0ca2006-07-12 16:44:04 -0500413 return error;
414}
415
416static int device_remove_lockspace(struct dlm_lspace_params *params)
417{
418 dlm_lockspace_t *lockspace;
419 struct dlm_ls *ls;
David Teiglandc6e6f0b2006-08-30 10:50:18 -0500420 int error, force = 0;
David Teigland597d0ca2006-07-12 16:44:04 -0500421
422 if (!capable(CAP_SYS_ADMIN))
423 return -EPERM;
424
425 ls = dlm_find_lockspace_device(params->minor);
426 if (!ls)
427 return -ENOENT;
428
David Teiglandc6e6f0b2006-08-30 10:50:18 -0500429 if (params->flags & DLM_USER_LSFLG_FORCEFREE)
430 force = 2;
431
David Teigland597d0ca2006-07-12 16:44:04 -0500432 lockspace = ls->ls_local_handle;
David Teigland597d0ca2006-07-12 16:44:04 -0500433 dlm_put_lockspace(ls);
David Teigland0f8e0d92008-08-06 13:30:24 -0500434
435 /* The final dlm_release_lockspace waits for references to go to
436 zero, so all processes will need to close their device for the
437 ls before the release will proceed. release also calls the
438 device_deregister above. Converting a positive return value
439 from release to zero means that userspace won't know when its
440 release was the final one, but it shouldn't need to know. */
441
David Teiglandc6e6f0b2006-08-30 10:50:18 -0500442 error = dlm_release_lockspace(lockspace, force);
David Teigland0f8e0d92008-08-06 13:30:24 -0500443 if (error > 0)
444 error = 0;
David Teigland597d0ca2006-07-12 16:44:04 -0500445 return error;
446}
447
448/* Check the user's version matches ours */
449static int check_version(struct dlm_write_request *req)
450{
451 if (req->version[0] != DLM_DEVICE_VERSION_MAJOR ||
452 (req->version[0] == DLM_DEVICE_VERSION_MAJOR &&
453 req->version[1] > DLM_DEVICE_VERSION_MINOR)) {
454
455 printk(KERN_DEBUG "dlm: process %s (%d) version mismatch "
456 "user (%d.%d.%d) kernel (%d.%d.%d)\n",
457 current->comm,
Pavel Emelyanovba25f9d2007-10-18 23:40:40 -0700458 task_pid_nr(current),
David Teigland597d0ca2006-07-12 16:44:04 -0500459 req->version[0],
460 req->version[1],
461 req->version[2],
462 DLM_DEVICE_VERSION_MAJOR,
463 DLM_DEVICE_VERSION_MINOR,
464 DLM_DEVICE_VERSION_PATCH);
465 return -EINVAL;
466 }
467 return 0;
468}
469
470/*
471 * device_write
472 *
473 * device_user_lock
474 * dlm_user_request -> request_lock
475 * dlm_user_convert -> convert_lock
476 *
477 * device_user_unlock
478 * dlm_user_unlock -> unlock_lock
479 * dlm_user_cancel -> cancel_lock
480 *
481 * device_create_lockspace
482 * dlm_new_lockspace
483 *
484 * device_remove_lockspace
485 * dlm_release_lockspace
486 */
487
488/* a write to a lockspace device is a lock or unlock request, a write
489 to the control device is to create/remove a lockspace */
490
491static ssize_t device_write(struct file *file, const char __user *buf,
492 size_t count, loff_t *ppos)
493{
494 struct dlm_user_proc *proc = file->private_data;
495 struct dlm_write_request *kbuf;
496 sigset_t tmpsig, allsigs;
497 int error;
498
499#ifdef CONFIG_COMPAT
500 if (count < sizeof(struct dlm_write_request32))
501#else
502 if (count < sizeof(struct dlm_write_request))
503#endif
504 return -EINVAL;
505
David Teiglandd4b0bcf2013-02-04 15:31:22 -0600506 /*
507 * can't compare against COMPAT/dlm_write_request32 because
508 * we don't yet know if is64bit is zero
509 */
Sasha Levin2b75bc92012-09-09 16:16:58 +0200510 if (count > sizeof(struct dlm_write_request) + DLM_RESNAME_MAXLEN)
Sasha Levin2b75bc92012-09-09 16:16:58 +0200511 return -EINVAL;
512
David Teigland573c24c2009-11-30 16:34:43 -0600513 kbuf = kzalloc(count + 1, GFP_NOFS);
David Teigland597d0ca2006-07-12 16:44:04 -0500514 if (!kbuf)
515 return -ENOMEM;
516
517 if (copy_from_user(kbuf, buf, count)) {
518 error = -EFAULT;
519 goto out_free;
520 }
521
522 if (check_version(kbuf)) {
523 error = -EBADE;
524 goto out_free;
525 }
526
527#ifdef CONFIG_COMPAT
528 if (!kbuf->is64bit) {
529 struct dlm_write_request32 *k32buf;
David Teigland1fecb1c2009-03-04 11:17:23 -0600530 int namelen = 0;
531
532 if (count > sizeof(struct dlm_write_request32))
533 namelen = count - sizeof(struct dlm_write_request32);
534
David Teigland597d0ca2006-07-12 16:44:04 -0500535 k32buf = (struct dlm_write_request32 *)kbuf;
David Teigland1fecb1c2009-03-04 11:17:23 -0600536
537 /* add 1 after namelen so that the name string is terminated */
538 kbuf = kzalloc(sizeof(struct dlm_write_request) + namelen + 1,
David Teigland573c24c2009-11-30 16:34:43 -0600539 GFP_NOFS);
David Teiglandcb980d92008-07-29 15:21:19 -0500540 if (!kbuf) {
541 kfree(k32buf);
David Teigland597d0ca2006-07-12 16:44:04 -0500542 return -ENOMEM;
David Teiglandcb980d92008-07-29 15:21:19 -0500543 }
David Teigland597d0ca2006-07-12 16:44:04 -0500544
545 if (proc)
546 set_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags);
David Teigland1fecb1c2009-03-04 11:17:23 -0600547
548 compat_input(kbuf, k32buf, namelen);
David Teigland597d0ca2006-07-12 16:44:04 -0500549 kfree(k32buf);
550 }
551#endif
552
553 /* do we really need this? can a write happen after a close? */
554 if ((kbuf->cmd == DLM_USER_LOCK || kbuf->cmd == DLM_USER_UNLOCK) &&
David Teiglandcb980d92008-07-29 15:21:19 -0500555 (proc && test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags))) {
556 error = -EINVAL;
557 goto out_free;
558 }
David Teigland597d0ca2006-07-12 16:44:04 -0500559
560 sigfillset(&allsigs);
561 sigprocmask(SIG_BLOCK, &allsigs, &tmpsig);
562
563 error = -EINVAL;
564
565 switch (kbuf->cmd)
566 {
567 case DLM_USER_LOCK:
568 if (!proc) {
569 log_print("no locking on control device");
570 goto out_sig;
571 }
572 error = device_user_lock(proc, &kbuf->i.lock);
573 break;
574
575 case DLM_USER_UNLOCK:
576 if (!proc) {
577 log_print("no locking on control device");
578 goto out_sig;
579 }
580 error = device_user_unlock(proc, &kbuf->i.lock);
581 break;
582
David Teigland8b4021f2007-05-29 08:46:00 -0500583 case DLM_USER_DEADLOCK:
584 if (!proc) {
585 log_print("no locking on control device");
586 goto out_sig;
587 }
588 error = device_user_deadlock(proc, &kbuf->i.lock);
589 break;
590
David Teigland597d0ca2006-07-12 16:44:04 -0500591 case DLM_USER_CREATE_LOCKSPACE:
592 if (proc) {
593 log_print("create/remove only on control device");
594 goto out_sig;
595 }
596 error = device_create_lockspace(&kbuf->i.lspace);
597 break;
598
599 case DLM_USER_REMOVE_LOCKSPACE:
600 if (proc) {
601 log_print("create/remove only on control device");
602 goto out_sig;
603 }
604 error = device_remove_lockspace(&kbuf->i.lspace);
605 break;
606
David Teigland72c2be72007-03-30 15:06:16 -0500607 case DLM_USER_PURGE:
608 if (!proc) {
609 log_print("no locking on control device");
610 goto out_sig;
611 }
612 error = device_user_purge(proc, &kbuf->i.purge);
613 break;
614
David Teigland597d0ca2006-07-12 16:44:04 -0500615 default:
616 log_print("Unknown command passed to DLM device : %d\n",
617 kbuf->cmd);
618 }
619
620 out_sig:
621 sigprocmask(SIG_SETMASK, &tmpsig, NULL);
David Teigland597d0ca2006-07-12 16:44:04 -0500622 out_free:
623 kfree(kbuf);
624 return error;
625}
626
627/* Every process that opens the lockspace device has its own "proc" structure
628 hanging off the open file that's used to keep track of locks owned by the
629 process and asts that need to be delivered to the process. */
630
631static int device_open(struct inode *inode, struct file *file)
632{
633 struct dlm_user_proc *proc;
634 struct dlm_ls *ls;
635
636 ls = dlm_find_lockspace_device(iminor(inode));
David Teiglandf9f2ed42008-09-04 12:51:20 -0500637 if (!ls)
David Teigland597d0ca2006-07-12 16:44:04 -0500638 return -ENOENT;
639
David Teigland573c24c2009-11-30 16:34:43 -0600640 proc = kzalloc(sizeof(struct dlm_user_proc), GFP_NOFS);
David Teigland597d0ca2006-07-12 16:44:04 -0500641 if (!proc) {
642 dlm_put_lockspace(ls);
643 return -ENOMEM;
644 }
645
646 proc->lockspace = ls->ls_local_handle;
647 INIT_LIST_HEAD(&proc->asts);
648 INIT_LIST_HEAD(&proc->locks);
David Teiglanda1bc86e2007-01-15 10:34:52 -0600649 INIT_LIST_HEAD(&proc->unlocking);
David Teigland597d0ca2006-07-12 16:44:04 -0500650 spin_lock_init(&proc->asts_spin);
651 spin_lock_init(&proc->locks_spin);
652 init_waitqueue_head(&proc->wait);
653 file->private_data = proc;
654
655 return 0;
656}
657
658static int device_close(struct inode *inode, struct file *file)
659{
660 struct dlm_user_proc *proc = file->private_data;
661 struct dlm_ls *ls;
662 sigset_t tmpsig, allsigs;
663
664 ls = dlm_find_lockspace_local(proc->lockspace);
665 if (!ls)
666 return -ENOENT;
667
668 sigfillset(&allsigs);
669 sigprocmask(SIG_BLOCK, &allsigs, &tmpsig);
670
671 set_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags);
672
673 dlm_clear_proc_locks(ls, proc);
674
675 /* at this point no more lkb's should exist for this lockspace,
676 so there's no chance of dlm_user_add_ast() being called and
677 looking for lkb->ua->proc */
678
679 kfree(proc);
680 file->private_data = NULL;
681
682 dlm_put_lockspace(ls);
683 dlm_put_lockspace(ls); /* for the find in device_open() */
684
685 /* FIXME: AUTOFREE: if this ls is no longer used do
686 device_remove_lockspace() */
687
688 sigprocmask(SIG_SETMASK, &tmpsig, NULL);
689 recalc_sigpending();
690
691 return 0;
692}
693
David Teigland8304d6f2011-02-21 14:58:21 -0600694static int copy_result_to_user(struct dlm_user_args *ua, int compat,
695 uint32_t flags, int mode, int copy_lvb,
696 char __user *buf, size_t count)
David Teigland597d0ca2006-07-12 16:44:04 -0500697{
698#ifdef CONFIG_COMPAT
699 struct dlm_lock_result32 result32;
700#endif
701 struct dlm_lock_result result;
702 void *resultptr;
703 int error=0;
704 int len;
705 int struct_len;
706
707 memset(&result, 0, sizeof(struct dlm_lock_result));
David Teiglandd7db9232007-05-18 09:00:32 -0500708 result.version[0] = DLM_DEVICE_VERSION_MAJOR;
709 result.version[1] = DLM_DEVICE_VERSION_MINOR;
710 result.version[2] = DLM_DEVICE_VERSION_PATCH;
David Teigland597d0ca2006-07-12 16:44:04 -0500711 memcpy(&result.lksb, &ua->lksb, sizeof(struct dlm_lksb));
712 result.user_lksb = ua->user_lksb;
713
714 /* FIXME: dlm1 provides for the user's bastparam/addr to not be updated
715 in a conversion unless the conversion is successful. See code
716 in dlm_user_convert() for updating ua from ua_tmp. OpenVMS, though,
717 notes that a new blocking AST address and parameter are set even if
718 the conversion fails, so maybe we should just do that. */
719
David Teigland8304d6f2011-02-21 14:58:21 -0600720 if (flags & DLM_CB_BAST) {
David Teigland597d0ca2006-07-12 16:44:04 -0500721 result.user_astaddr = ua->bastaddr;
722 result.user_astparam = ua->bastparam;
David Teigland89d799d2010-03-25 14:23:13 -0500723 result.bast_mode = mode;
David Teigland597d0ca2006-07-12 16:44:04 -0500724 } else {
725 result.user_astaddr = ua->castaddr;
726 result.user_astparam = ua->castparam;
727 }
728
729#ifdef CONFIG_COMPAT
730 if (compat)
731 len = sizeof(struct dlm_lock_result32);
732 else
733#endif
734 len = sizeof(struct dlm_lock_result);
735 struct_len = len;
736
737 /* copy lvb to userspace if there is one, it's been updated, and
738 the user buffer has space for it */
739
David Teigland8304d6f2011-02-21 14:58:21 -0600740 if (copy_lvb && ua->lksb.sb_lvbptr && count >= len + DLM_USER_LVB_LEN) {
David Teigland597d0ca2006-07-12 16:44:04 -0500741 if (copy_to_user(buf+len, ua->lksb.sb_lvbptr,
742 DLM_USER_LVB_LEN)) {
743 error = -EFAULT;
744 goto out;
745 }
746
747 result.lvb_offset = len;
748 len += DLM_USER_LVB_LEN;
749 }
750
751 result.length = len;
752 resultptr = &result;
753#ifdef CONFIG_COMPAT
754 if (compat) {
755 compat_output(&result, &result32);
756 resultptr = &result32;
757 }
758#endif
759
760 if (copy_to_user(buf, resultptr, struct_len))
761 error = -EFAULT;
762 else
763 error = len;
764 out:
765 return error;
766}
767
David Teiglandd7db9232007-05-18 09:00:32 -0500768static int copy_version_to_user(char __user *buf, size_t count)
769{
770 struct dlm_device_version ver;
771
772 memset(&ver, 0, sizeof(struct dlm_device_version));
773 ver.version[0] = DLM_DEVICE_VERSION_MAJOR;
774 ver.version[1] = DLM_DEVICE_VERSION_MINOR;
775 ver.version[2] = DLM_DEVICE_VERSION_PATCH;
776
777 if (copy_to_user(buf, &ver, sizeof(struct dlm_device_version)))
778 return -EFAULT;
779 return sizeof(struct dlm_device_version);
780}
781
David Teigland597d0ca2006-07-12 16:44:04 -0500782/* a read returns a single ast described in a struct dlm_lock_result */
783
784static ssize_t device_read(struct file *file, char __user *buf, size_t count,
785 loff_t *ppos)
786{
787 struct dlm_user_proc *proc = file->private_data;
788 struct dlm_lkb *lkb;
David Teigland597d0ca2006-07-12 16:44:04 -0500789 DECLARE_WAITQUEUE(wait, current);
David Teigland8304d6f2011-02-21 14:58:21 -0600790 struct dlm_callback cb;
791 int rv, resid, copy_lvb = 0;
David Teigland597d0ca2006-07-12 16:44:04 -0500792
David Teiglandd7db9232007-05-18 09:00:32 -0500793 if (count == sizeof(struct dlm_device_version)) {
David Teigland8304d6f2011-02-21 14:58:21 -0600794 rv = copy_version_to_user(buf, count);
795 return rv;
David Teiglandd7db9232007-05-18 09:00:32 -0500796 }
797
798 if (!proc) {
799 log_print("non-version read from control device %zu", count);
800 return -EINVAL;
801 }
802
David Teigland597d0ca2006-07-12 16:44:04 -0500803#ifdef CONFIG_COMPAT
804 if (count < sizeof(struct dlm_lock_result32))
805#else
806 if (count < sizeof(struct dlm_lock_result))
807#endif
808 return -EINVAL;
809
David Teigland89d799d2010-03-25 14:23:13 -0500810 try_another:
811
David Teigland597d0ca2006-07-12 16:44:04 -0500812 /* do we really need this? can a read happen after a close? */
813 if (test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags))
814 return -EINVAL;
815
816 spin_lock(&proc->asts_spin);
817 if (list_empty(&proc->asts)) {
818 if (file->f_flags & O_NONBLOCK) {
819 spin_unlock(&proc->asts_spin);
820 return -EAGAIN;
821 }
822
823 add_wait_queue(&proc->wait, &wait);
824
825 repeat:
826 set_current_state(TASK_INTERRUPTIBLE);
827 if (list_empty(&proc->asts) && !signal_pending(current)) {
828 spin_unlock(&proc->asts_spin);
829 schedule();
830 spin_lock(&proc->asts_spin);
831 goto repeat;
832 }
833 set_current_state(TASK_RUNNING);
834 remove_wait_queue(&proc->wait, &wait);
835
836 if (signal_pending(current)) {
837 spin_unlock(&proc->asts_spin);
838 return -ERESTARTSYS;
839 }
840 }
841
David Teigland8304d6f2011-02-21 14:58:21 -0600842 /* if we empty lkb_callbacks, we don't want to unlock the spinlock
David Teigland23e8e1a2011-04-05 13:16:24 -0500843 without removing lkb_cb_list; so empty lkb_cb_list is always
David Teigland8304d6f2011-02-21 14:58:21 -0600844 consistent with empty lkb_callbacks */
David Teigland597d0ca2006-07-12 16:44:04 -0500845
David Teigland23e8e1a2011-04-05 13:16:24 -0500846 lkb = list_entry(proc->asts.next, struct dlm_lkb, lkb_cb_list);
David Teigland597d0ca2006-07-12 16:44:04 -0500847
David Teigland8304d6f2011-02-21 14:58:21 -0600848 rv = dlm_rem_lkb_callback(lkb->lkb_resource->res_ls, lkb, &cb, &resid);
849 if (rv < 0) {
850 /* this shouldn't happen; lkb should have been removed from
851 list when resid was zero */
852 log_print("dlm_rem_lkb_callback empty %x", lkb->lkb_id);
David Teigland23e8e1a2011-04-05 13:16:24 -0500853 list_del_init(&lkb->lkb_cb_list);
David Teigland8304d6f2011-02-21 14:58:21 -0600854 spin_unlock(&proc->asts_spin);
855 /* removes ref for proc->asts, may cause lkb to be freed */
856 dlm_put_lkb(lkb);
857 goto try_another;
David Teigland89d799d2010-03-25 14:23:13 -0500858 }
David Teigland8304d6f2011-02-21 14:58:21 -0600859 if (!resid)
David Teigland23e8e1a2011-04-05 13:16:24 -0500860 list_del_init(&lkb->lkb_cb_list);
David Teigland597d0ca2006-07-12 16:44:04 -0500861 spin_unlock(&proc->asts_spin);
862
David Teigland8304d6f2011-02-21 14:58:21 -0600863 if (cb.flags & DLM_CB_SKIP) {
864 /* removes ref for proc->asts, may cause lkb to be freed */
865 if (!resid)
866 dlm_put_lkb(lkb);
867 goto try_another;
David Teigland89d799d2010-03-25 14:23:13 -0500868 }
David Teigland597d0ca2006-07-12 16:44:04 -0500869
David Teigland8304d6f2011-02-21 14:58:21 -0600870 if (cb.flags & DLM_CB_CAST) {
871 int old_mode, new_mode;
David Teigland89d799d2010-03-25 14:23:13 -0500872
David Teigland8304d6f2011-02-21 14:58:21 -0600873 old_mode = lkb->lkb_last_cast.mode;
874 new_mode = cb.mode;
875
876 if (!cb.sb_status && lkb->lkb_lksb->sb_lvbptr &&
877 dlm_lvb_operations[old_mode + 1][new_mode + 1])
878 copy_lvb = 1;
879
880 lkb->lkb_lksb->sb_status = cb.sb_status;
881 lkb->lkb_lksb->sb_flags = cb.sb_flags;
882 }
883
884 rv = copy_result_to_user(lkb->lkb_ua,
885 test_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags),
886 cb.flags, cb.mode, copy_lvb, buf, count);
887
888 /* removes ref for proc->asts, may cause lkb to be freed */
889 if (!resid)
David Teigland597d0ca2006-07-12 16:44:04 -0500890 dlm_put_lkb(lkb);
891
David Teigland8304d6f2011-02-21 14:58:21 -0600892 return rv;
David Teigland597d0ca2006-07-12 16:44:04 -0500893}
894
895static unsigned int device_poll(struct file *file, poll_table *wait)
896{
897 struct dlm_user_proc *proc = file->private_data;
898
899 poll_wait(file, &proc->wait, wait);
900
901 spin_lock(&proc->asts_spin);
902 if (!list_empty(&proc->asts)) {
903 spin_unlock(&proc->asts_spin);
904 return POLLIN | POLLRDNORM;
905 }
906 spin_unlock(&proc->asts_spin);
907 return 0;
908}
909
David Teiglanddc68c7e2008-08-18 11:43:30 -0500910int dlm_user_daemon_available(void)
911{
912 /* dlm_controld hasn't started (or, has started, but not
913 properly populated configfs) */
914
915 if (!dlm_our_nodeid())
916 return 0;
917
918 /* This is to deal with versions of dlm_controld that don't
919 know about the monitor device. We assume that if the
920 dlm_controld was started (above), but the monitor device
921 was never opened, that it's an old version. dlm_controld
922 should open the monitor device before populating configfs. */
923
924 if (dlm_monitor_unused)
925 return 1;
926
927 return atomic_read(&dlm_monitor_opened) ? 1 : 0;
928}
929
David Teigland597d0ca2006-07-12 16:44:04 -0500930static int ctl_device_open(struct inode *inode, struct file *file)
931{
932 file->private_data = NULL;
933 return 0;
934}
935
936static int ctl_device_close(struct inode *inode, struct file *file)
937{
938 return 0;
939}
940
David Teiglanddc68c7e2008-08-18 11:43:30 -0500941static int monitor_device_open(struct inode *inode, struct file *file)
942{
943 atomic_inc(&dlm_monitor_opened);
944 dlm_monitor_unused = 0;
945 return 0;
946}
947
948static int monitor_device_close(struct inode *inode, struct file *file)
949{
950 if (atomic_dec_and_test(&dlm_monitor_opened))
951 dlm_stop_lockspaces();
952 return 0;
953}
954
Arjan van de Ven00977a52007-02-12 00:55:34 -0800955static const struct file_operations device_fops = {
David Teigland597d0ca2006-07-12 16:44:04 -0500956 .open = device_open,
957 .release = device_close,
958 .read = device_read,
959 .write = device_write,
960 .poll = device_poll,
961 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200962 .llseek = noop_llseek,
David Teigland597d0ca2006-07-12 16:44:04 -0500963};
964
Arjan van de Ven00977a52007-02-12 00:55:34 -0800965static const struct file_operations ctl_device_fops = {
David Teigland597d0ca2006-07-12 16:44:04 -0500966 .open = ctl_device_open,
967 .release = ctl_device_close,
David Teiglandd7db9232007-05-18 09:00:32 -0500968 .read = device_read,
David Teigland597d0ca2006-07-12 16:44:04 -0500969 .write = device_write,
970 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200971 .llseek = noop_llseek,
David Teigland597d0ca2006-07-12 16:44:04 -0500972};
973
Denis Cheng0fe410d2008-01-29 13:50:16 +0800974static struct miscdevice ctl_device = {
975 .name = "dlm-control",
976 .fops = &ctl_device_fops,
977 .minor = MISC_DYNAMIC_MINOR,
978};
979
David Teiglanddc68c7e2008-08-18 11:43:30 -0500980static const struct file_operations monitor_device_fops = {
981 .open = monitor_device_open,
982 .release = monitor_device_close,
983 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200984 .llseek = noop_llseek,
David Teiglanddc68c7e2008-08-18 11:43:30 -0500985};
986
987static struct miscdevice monitor_device = {
988 .name = "dlm-monitor",
989 .fops = &monitor_device_fops,
990 .minor = MISC_DYNAMIC_MINOR,
991};
992
Denis Cheng30727172008-02-02 01:53:46 +0800993int __init dlm_user_init(void)
David Teigland597d0ca2006-07-12 16:44:04 -0500994{
995 int error;
996
David Teiglanddc68c7e2008-08-18 11:43:30 -0500997 atomic_set(&dlm_monitor_opened, 0);
David Teigland597d0ca2006-07-12 16:44:04 -0500998
David Teiglanddc68c7e2008-08-18 11:43:30 -0500999 error = misc_register(&ctl_device);
1000 if (error) {
1001 log_print("misc_register failed for control device");
1002 goto out;
1003 }
1004
1005 error = misc_register(&monitor_device);
1006 if (error) {
1007 log_print("misc_register failed for monitor device");
1008 misc_deregister(&ctl_device);
1009 }
1010 out:
David Teigland597d0ca2006-07-12 16:44:04 -05001011 return error;
1012}
1013
1014void dlm_user_exit(void)
1015{
1016 misc_deregister(&ctl_device);
David Teiglanddc68c7e2008-08-18 11:43:30 -05001017 misc_deregister(&monitor_device);
David Teigland597d0ca2006-07-12 16:44:04 -05001018}
1019