2 * Copyright (C) 2006-2010 Red Hat, Inc. All rights reserved.
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.
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>
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>
20 #include <linux/slab.h>
22 #include "dlm_internal.h"
23 #include "lockspace.h"
25 #include "lvb_table.h"
29 static const char name_prefix
[] = "dlm";
30 static const struct file_operations device_fops
;
31 static atomic_t dlm_monitor_opened
;
32 static int dlm_monitor_unused
= 1;
36 struct dlm_lock_params32
{
50 char lvb
[DLM_USER_LVB_LEN
];
54 struct dlm_write_request32
{
61 struct dlm_lock_params32 lock
;
62 struct dlm_lspace_params lspace
;
63 struct dlm_purge_params purge
;
74 struct dlm_lock_result32
{
80 struct dlm_lksb32 lksb
;
83 /* Offsets may be zero if no data is present */
87 static void compat_input(struct dlm_write_request
*kb
,
88 struct dlm_write_request32
*kb32
,
91 kb
->version
[0] = kb32
->version
[0];
92 kb
->version
[1] = kb32
->version
[1];
93 kb
->version
[2] = kb32
->version
[2];
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
;
101 memcpy(kb
->i
.lspace
.name
, kb32
->i
.lspace
.name
, namelen
);
102 } 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
;
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
;
111 kb
->i
.lock
.xid
= kb32
->i
.lock
.xid
;
112 kb
->i
.lock
.timeout
= kb32
->i
.lock
.timeout
;
113 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
);
119 memcpy(kb
->i
.lock
.name
, kb32
->i
.lock
.name
, namelen
);
123 static void compat_output(struct dlm_lock_result
*res
,
124 struct dlm_lock_result32
*res32
)
126 res32
->version
[0] = res
->version
[0];
127 res32
->version
[1] = res
->version
[1];
128 res32
->version
[2] = res
->version
[2];
130 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
;
135 res32
->lvb_offset
= res
->lvb_offset
;
136 res32
->length
= res
->length
;
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
;
145 /* 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. */
156 static int lkb_is_endoflife(int mode
, int status
)
165 if (mode
== DLM_LOCK_IV
)
172 /* 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 */
175 void dlm_user_add_ast(struct dlm_lkb
*lkb
, uint32_t flags
, int mode
,
176 int status
, uint32_t sbflags
, uint64_t seq
)
179 struct dlm_user_args
*ua
;
180 struct dlm_user_proc
*proc
;
183 if (lkb
->lkb_flags
& (DLM_IFL_ORPHAN
| DLM_IFL_DEAD
))
186 ls
= lkb
->lkb_resource
->res_ls
;
187 mutex_lock(&ls
->ls_clear_proc_locks
);
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
191 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. */
195 if (lkb
->lkb_flags
& (DLM_IFL_ORPHAN
| DLM_IFL_DEAD
))
198 DLM_ASSERT(lkb
->lkb_ua
, dlm_print_lkb(lkb
););
202 if ((flags
& DLM_CB_BAST
) && ua
->bastaddr
== NULL
)
205 if ((flags
& DLM_CB_CAST
) && lkb_is_endoflife(mode
, status
))
206 lkb
->lkb_flags
|= DLM_IFL_ENDOFLIFE
;
208 spin_lock(&proc
->asts_spin
);
210 rv
= dlm_add_lkb_callback(lkb
, flags
, mode
, status
, sbflags
, seq
);
212 spin_unlock(&proc
->asts_spin
);
216 if (list_empty(&lkb
->lkb_cb_list
)) {
217 kref_get(&lkb
->lkb_ref
);
218 list_add_tail(&lkb
->lkb_cb_list
, &proc
->asts
);
219 wake_up_interruptible(&proc
->wait
);
221 spin_unlock(&proc
->asts_spin
);
223 if (lkb
->lkb_flags
& DLM_IFL_ENDOFLIFE
) {
224 /* N.B. spin_lock locks_spin, not asts_spin */
225 spin_lock(&proc
->locks_spin
);
226 if (!list_empty(&lkb
->lkb_ownqueue
)) {
227 list_del_init(&lkb
->lkb_ownqueue
);
230 spin_unlock(&proc
->locks_spin
);
233 mutex_unlock(&ls
->ls_clear_proc_locks
);
236 static int device_user_lock(struct dlm_user_proc
*proc
,
237 struct dlm_lock_params
*params
)
240 struct dlm_user_args
*ua
;
243 ls
= dlm_find_lockspace_local(proc
->lockspace
);
247 if (!params
->castaddr
|| !params
->lksb
) {
252 ua
= kzalloc(sizeof(struct dlm_user_args
), GFP_NOFS
);
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
;
261 ua
->xid
= params
->xid
;
263 if (params
->flags
& DLM_LKF_CONVERT
)
264 error
= dlm_user_convert(ls
, ua
,
265 params
->mode
, params
->flags
,
266 params
->lkid
, params
->lvb
,
267 (unsigned long) params
->timeout
);
269 error
= dlm_user_request(ls
, ua
,
270 params
->mode
, params
->flags
,
271 params
->name
, params
->namelen
,
272 (unsigned long) params
->timeout
);
274 error
= ua
->lksb
.sb_lkid
;
277 dlm_put_lockspace(ls
);
281 static int device_user_unlock(struct dlm_user_proc
*proc
,
282 struct dlm_lock_params
*params
)
285 struct dlm_user_args
*ua
;
288 ls
= dlm_find_lockspace_local(proc
->lockspace
);
292 ua
= kzalloc(sizeof(struct dlm_user_args
), GFP_NOFS
);
296 ua
->user_lksb
= params
->lksb
;
297 ua
->castparam
= params
->castparam
;
298 ua
->castaddr
= params
->castaddr
;
300 if (params
->flags
& DLM_LKF_CANCEL
)
301 error
= dlm_user_cancel(ls
, ua
, params
->flags
, params
->lkid
);
303 error
= dlm_user_unlock(ls
, ua
, params
->flags
, params
->lkid
,
306 dlm_put_lockspace(ls
);
310 static int device_user_deadlock(struct dlm_user_proc
*proc
,
311 struct dlm_lock_params
*params
)
316 ls
= dlm_find_lockspace_local(proc
->lockspace
);
320 error
= dlm_user_deadlock(ls
, params
->flags
, params
->lkid
);
322 dlm_put_lockspace(ls
);
326 static int dlm_device_register(struct dlm_ls
*ls
, char *name
)
330 /* The device is already registered. This happens when the
331 lockspace is created multiple times from userspace. */
332 if (ls
->ls_device
.name
)
336 len
= strlen(name
) + strlen(name_prefix
) + 2;
337 ls
->ls_device
.name
= kzalloc(len
, GFP_NOFS
);
338 if (!ls
->ls_device
.name
)
341 snprintf((char *)ls
->ls_device
.name
, len
, "%s_%s", name_prefix
,
343 ls
->ls_device
.fops
= &device_fops
;
344 ls
->ls_device
.minor
= MISC_DYNAMIC_MINOR
;
346 error
= misc_register(&ls
->ls_device
);
348 kfree(ls
->ls_device
.name
);
354 int dlm_device_deregister(struct dlm_ls
*ls
)
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
)
364 error
= misc_deregister(&ls
->ls_device
);
366 kfree(ls
->ls_device
.name
);
370 static int device_user_purge(struct dlm_user_proc
*proc
,
371 struct dlm_purge_params
*params
)
376 ls
= dlm_find_lockspace_local(proc
->lockspace
);
380 error
= dlm_user_purge(ls
, proc
, params
->nodeid
, params
->pid
);
382 dlm_put_lockspace(ls
);
386 static int device_create_lockspace(struct dlm_lspace_params
*params
)
388 dlm_lockspace_t
*lockspace
;
392 if (!capable(CAP_SYS_ADMIN
))
395 error
= dlm_new_lockspace(params
->name
, NULL
, params
->flags
,
396 DLM_USER_LVB_LEN
, NULL
, NULL
, NULL
,
401 ls
= dlm_find_lockspace_local(lockspace
);
405 error
= dlm_device_register(ls
, params
->name
);
406 dlm_put_lockspace(ls
);
409 dlm_release_lockspace(lockspace
, 0);
411 error
= ls
->ls_device
.minor
;
416 static int device_remove_lockspace(struct dlm_lspace_params
*params
)
418 dlm_lockspace_t
*lockspace
;
420 int error
, force
= 0;
422 if (!capable(CAP_SYS_ADMIN
))
425 ls
= dlm_find_lockspace_device(params
->minor
);
429 if (params
->flags
& DLM_USER_LSFLG_FORCEFREE
)
432 lockspace
= ls
->ls_local_handle
;
433 dlm_put_lockspace(ls
);
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. */
442 error
= dlm_release_lockspace(lockspace
, force
);
448 /* Check the user's version matches ours */
449 static int check_version(struct dlm_write_request
*req
)
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
)) {
455 printk(KERN_DEBUG
"dlm: process %s (%d) version mismatch "
456 "user (%d.%d.%d) kernel (%d.%d.%d)\n",
458 task_pid_nr(current
),
462 DLM_DEVICE_VERSION_MAJOR
,
463 DLM_DEVICE_VERSION_MINOR
,
464 DLM_DEVICE_VERSION_PATCH
);
474 * dlm_user_request -> request_lock
475 * dlm_user_convert -> convert_lock
478 * dlm_user_unlock -> unlock_lock
479 * dlm_user_cancel -> cancel_lock
481 * device_create_lockspace
484 * device_remove_lockspace
485 * dlm_release_lockspace
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 */
491 static ssize_t
device_write(struct file
*file
, const char __user
*buf
,
492 size_t count
, loff_t
*ppos
)
494 struct dlm_user_proc
*proc
= file
->private_data
;
495 struct dlm_write_request
*kbuf
;
496 sigset_t tmpsig
, allsigs
;
500 if (count
< sizeof(struct dlm_write_request32
))
502 if (count
< sizeof(struct dlm_write_request
))
507 if (count
> sizeof(struct dlm_write_request32
) + DLM_RESNAME_MAXLEN
)
509 if (count
> sizeof(struct dlm_write_request
) + DLM_RESNAME_MAXLEN
)
513 kbuf
= kzalloc(count
+ 1, GFP_NOFS
);
517 if (copy_from_user(kbuf
, buf
, count
)) {
522 if (check_version(kbuf
)) {
528 if (!kbuf
->is64bit
) {
529 struct dlm_write_request32
*k32buf
;
532 if (count
> sizeof(struct dlm_write_request32
))
533 namelen
= count
- sizeof(struct dlm_write_request32
);
535 k32buf
= (struct dlm_write_request32
*)kbuf
;
537 /* add 1 after namelen so that the name string is terminated */
538 kbuf
= kzalloc(sizeof(struct dlm_write_request
) + namelen
+ 1,
546 set_bit(DLM_PROC_FLAGS_COMPAT
, &proc
->flags
);
548 compat_input(kbuf
, k32buf
, namelen
);
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
) &&
555 (proc
&& test_bit(DLM_PROC_FLAGS_CLOSING
, &proc
->flags
))) {
560 sigfillset(&allsigs
);
561 sigprocmask(SIG_BLOCK
, &allsigs
, &tmpsig
);
569 log_print("no locking on control device");
572 error
= device_user_lock(proc
, &kbuf
->i
.lock
);
575 case DLM_USER_UNLOCK
:
577 log_print("no locking on control device");
580 error
= device_user_unlock(proc
, &kbuf
->i
.lock
);
583 case DLM_USER_DEADLOCK
:
585 log_print("no locking on control device");
588 error
= device_user_deadlock(proc
, &kbuf
->i
.lock
);
591 case DLM_USER_CREATE_LOCKSPACE
:
593 log_print("create/remove only on control device");
596 error
= device_create_lockspace(&kbuf
->i
.lspace
);
599 case DLM_USER_REMOVE_LOCKSPACE
:
601 log_print("create/remove only on control device");
604 error
= device_remove_lockspace(&kbuf
->i
.lspace
);
609 log_print("no locking on control device");
612 error
= device_user_purge(proc
, &kbuf
->i
.purge
);
616 log_print("Unknown command passed to DLM device : %d\n",
621 sigprocmask(SIG_SETMASK
, &tmpsig
, NULL
);
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. */
631 static int device_open(struct inode
*inode
, struct file
*file
)
633 struct dlm_user_proc
*proc
;
636 ls
= dlm_find_lockspace_device(iminor(inode
));
640 proc
= kzalloc(sizeof(struct dlm_user_proc
), GFP_NOFS
);
642 dlm_put_lockspace(ls
);
646 proc
->lockspace
= ls
->ls_local_handle
;
647 INIT_LIST_HEAD(&proc
->asts
);
648 INIT_LIST_HEAD(&proc
->locks
);
649 INIT_LIST_HEAD(&proc
->unlocking
);
650 spin_lock_init(&proc
->asts_spin
);
651 spin_lock_init(&proc
->locks_spin
);
652 init_waitqueue_head(&proc
->wait
);
653 file
->private_data
= proc
;
658 static int device_close(struct inode
*inode
, struct file
*file
)
660 struct dlm_user_proc
*proc
= file
->private_data
;
662 sigset_t tmpsig
, allsigs
;
664 ls
= dlm_find_lockspace_local(proc
->lockspace
);
668 sigfillset(&allsigs
);
669 sigprocmask(SIG_BLOCK
, &allsigs
, &tmpsig
);
671 set_bit(DLM_PROC_FLAGS_CLOSING
, &proc
->flags
);
673 dlm_clear_proc_locks(ls
, proc
);
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 */
680 file
->private_data
= NULL
;
682 dlm_put_lockspace(ls
);
683 dlm_put_lockspace(ls
); /* for the find in device_open() */
685 /* FIXME: AUTOFREE: if this ls is no longer used do
686 device_remove_lockspace() */
688 sigprocmask(SIG_SETMASK
, &tmpsig
, NULL
);
694 static 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
)
699 struct dlm_lock_result32 result32
;
701 struct dlm_lock_result result
;
707 memset(&result
, 0, sizeof(struct dlm_lock_result
));
708 result
.version
[0] = DLM_DEVICE_VERSION_MAJOR
;
709 result
.version
[1] = DLM_DEVICE_VERSION_MINOR
;
710 result
.version
[2] = DLM_DEVICE_VERSION_PATCH
;
711 memcpy(&result
.lksb
, &ua
->lksb
, sizeof(struct dlm_lksb
));
712 result
.user_lksb
= ua
->user_lksb
;
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. */
720 if (flags
& DLM_CB_BAST
) {
721 result
.user_astaddr
= ua
->bastaddr
;
722 result
.user_astparam
= ua
->bastparam
;
723 result
.bast_mode
= mode
;
725 result
.user_astaddr
= ua
->castaddr
;
726 result
.user_astparam
= ua
->castparam
;
731 len
= sizeof(struct dlm_lock_result32
);
734 len
= sizeof(struct dlm_lock_result
);
737 /* copy lvb to userspace if there is one, it's been updated, and
738 the user buffer has space for it */
740 if (copy_lvb
&& ua
->lksb
.sb_lvbptr
&& count
>= len
+ DLM_USER_LVB_LEN
) {
741 if (copy_to_user(buf
+len
, ua
->lksb
.sb_lvbptr
,
747 result
.lvb_offset
= len
;
748 len
+= DLM_USER_LVB_LEN
;
755 compat_output(&result
, &result32
);
756 resultptr
= &result32
;
760 if (copy_to_user(buf
, resultptr
, struct_len
))
768 static int copy_version_to_user(char __user
*buf
, size_t count
)
770 struct dlm_device_version ver
;
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
;
777 if (copy_to_user(buf
, &ver
, sizeof(struct dlm_device_version
)))
779 return sizeof(struct dlm_device_version
);
782 /* a read returns a single ast described in a struct dlm_lock_result */
784 static ssize_t
device_read(struct file
*file
, char __user
*buf
, size_t count
,
787 struct dlm_user_proc
*proc
= file
->private_data
;
789 DECLARE_WAITQUEUE(wait
, current
);
790 struct dlm_callback cb
;
791 int rv
, resid
, copy_lvb
= 0;
793 if (count
== sizeof(struct dlm_device_version
)) {
794 rv
= copy_version_to_user(buf
, count
);
799 log_print("non-version read from control device %zu", count
);
804 if (count
< sizeof(struct dlm_lock_result32
))
806 if (count
< sizeof(struct dlm_lock_result
))
812 /* do we really need this? can a read happen after a close? */
813 if (test_bit(DLM_PROC_FLAGS_CLOSING
, &proc
->flags
))
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
);
823 add_wait_queue(&proc
->wait
, &wait
);
826 set_current_state(TASK_INTERRUPTIBLE
);
827 if (list_empty(&proc
->asts
) && !signal_pending(current
)) {
828 spin_unlock(&proc
->asts_spin
);
830 spin_lock(&proc
->asts_spin
);
833 set_current_state(TASK_RUNNING
);
834 remove_wait_queue(&proc
->wait
, &wait
);
836 if (signal_pending(current
)) {
837 spin_unlock(&proc
->asts_spin
);
842 /* if we empty lkb_callbacks, we don't want to unlock the spinlock
843 without removing lkb_cb_list; so empty lkb_cb_list is always
844 consistent with empty lkb_callbacks */
846 lkb
= list_entry(proc
->asts
.next
, struct dlm_lkb
, lkb_cb_list
);
848 rv
= dlm_rem_lkb_callback(lkb
->lkb_resource
->res_ls
, lkb
, &cb
, &resid
);
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
);
853 list_del_init(&lkb
->lkb_cb_list
);
854 spin_unlock(&proc
->asts_spin
);
855 /* removes ref for proc->asts, may cause lkb to be freed */
860 list_del_init(&lkb
->lkb_cb_list
);
861 spin_unlock(&proc
->asts_spin
);
863 if (cb
.flags
& DLM_CB_SKIP
) {
864 /* removes ref for proc->asts, may cause lkb to be freed */
870 if (cb
.flags
& DLM_CB_CAST
) {
871 int old_mode
, new_mode
;
873 old_mode
= lkb
->lkb_last_cast
.mode
;
876 if (!cb
.sb_status
&& lkb
->lkb_lksb
->sb_lvbptr
&&
877 dlm_lvb_operations
[old_mode
+ 1][new_mode
+ 1])
880 lkb
->lkb_lksb
->sb_status
= cb
.sb_status
;
881 lkb
->lkb_lksb
->sb_flags
= cb
.sb_flags
;
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
);
888 /* removes ref for proc->asts, may cause lkb to be freed */
895 static unsigned int device_poll(struct file
*file
, poll_table
*wait
)
897 struct dlm_user_proc
*proc
= file
->private_data
;
899 poll_wait(file
, &proc
->wait
, wait
);
901 spin_lock(&proc
->asts_spin
);
902 if (!list_empty(&proc
->asts
)) {
903 spin_unlock(&proc
->asts_spin
);
904 return POLLIN
| POLLRDNORM
;
906 spin_unlock(&proc
->asts_spin
);
910 int dlm_user_daemon_available(void)
912 /* dlm_controld hasn't started (or, has started, but not
913 properly populated configfs) */
915 if (!dlm_our_nodeid())
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. */
924 if (dlm_monitor_unused
)
927 return atomic_read(&dlm_monitor_opened
) ? 1 : 0;
930 static int ctl_device_open(struct inode
*inode
, struct file
*file
)
932 file
->private_data
= NULL
;
936 static int ctl_device_close(struct inode
*inode
, struct file
*file
)
941 static int monitor_device_open(struct inode
*inode
, struct file
*file
)
943 atomic_inc(&dlm_monitor_opened
);
944 dlm_monitor_unused
= 0;
948 static int monitor_device_close(struct inode
*inode
, struct file
*file
)
950 if (atomic_dec_and_test(&dlm_monitor_opened
))
951 dlm_stop_lockspaces();
955 static const struct file_operations device_fops
= {
957 .release
= device_close
,
959 .write
= device_write
,
961 .owner
= THIS_MODULE
,
962 .llseek
= noop_llseek
,
965 static const struct file_operations ctl_device_fops
= {
966 .open
= ctl_device_open
,
967 .release
= ctl_device_close
,
969 .write
= device_write
,
970 .owner
= THIS_MODULE
,
971 .llseek
= noop_llseek
,
974 static struct miscdevice ctl_device
= {
975 .name
= "dlm-control",
976 .fops
= &ctl_device_fops
,
977 .minor
= MISC_DYNAMIC_MINOR
,
980 static const struct file_operations monitor_device_fops
= {
981 .open
= monitor_device_open
,
982 .release
= monitor_device_close
,
983 .owner
= THIS_MODULE
,
984 .llseek
= noop_llseek
,
987 static struct miscdevice monitor_device
= {
988 .name
= "dlm-monitor",
989 .fops
= &monitor_device_fops
,
990 .minor
= MISC_DYNAMIC_MINOR
,
993 int __init
dlm_user_init(void)
997 atomic_set(&dlm_monitor_opened
, 0);
999 error
= misc_register(&ctl_device
);
1001 log_print("misc_register failed for control device");
1005 error
= misc_register(&monitor_device
);
1007 log_print("misc_register failed for monitor device");
1008 misc_deregister(&ctl_device
);
1014 void dlm_user_exit(void)
1016 misc_deregister(&ctl_device
);
1017 misc_deregister(&monitor_device
);