Commit | Line | Data |
---|---|---|
597d0cae | 1 | /* |
ef0c2bb0 | 2 | * Copyright (C) 2006-2007 Red Hat, Inc. All rights reserved. |
597d0cae DT |
3 | * |
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> | |
20 | ||
21 | #include "dlm_internal.h" | |
22 | #include "lockspace.h" | |
23 | #include "lock.h" | |
24 | #include "lvb_table.h" | |
84c6e8cd | 25 | #include "user.h" |
597d0cae DT |
26 | |
27 | static const char *name_prefix="dlm"; | |
28 | static struct miscdevice ctl_device; | |
00977a59 | 29 | static const struct file_operations device_fops; |
597d0cae DT |
30 | |
31 | #ifdef CONFIG_COMPAT | |
32 | ||
33 | struct dlm_lock_params32 { | |
34 | __u8 mode; | |
35 | __u8 namelen; | |
36 | __u16 flags; | |
37 | __u32 lkid; | |
38 | __u32 parent; | |
39 | ||
40 | __u32 castparam; | |
41 | __u32 castaddr; | |
42 | __u32 bastparam; | |
43 | __u32 bastaddr; | |
44 | __u32 lksb; | |
45 | ||
46 | char lvb[DLM_USER_LVB_LEN]; | |
47 | char name[0]; | |
48 | }; | |
49 | ||
50 | struct dlm_write_request32 { | |
51 | __u32 version[3]; | |
52 | __u8 cmd; | |
53 | __u8 is64bit; | |
54 | __u8 unused[2]; | |
55 | ||
56 | union { | |
57 | struct dlm_lock_params32 lock; | |
58 | struct dlm_lspace_params lspace; | |
72c2be77 | 59 | struct dlm_purge_params purge; |
597d0cae DT |
60 | } i; |
61 | }; | |
62 | ||
63 | struct dlm_lksb32 { | |
64 | __u32 sb_status; | |
65 | __u32 sb_lkid; | |
66 | __u8 sb_flags; | |
67 | __u32 sb_lvbptr; | |
68 | }; | |
69 | ||
70 | struct dlm_lock_result32 { | |
71 | __u32 length; | |
72 | __u32 user_astaddr; | |
73 | __u32 user_astparam; | |
74 | __u32 user_lksb; | |
75 | struct dlm_lksb32 lksb; | |
76 | __u8 bast_mode; | |
77 | __u8 unused[3]; | |
78 | /* Offsets may be zero if no data is present */ | |
79 | __u32 lvb_offset; | |
80 | }; | |
81 | ||
82 | static void compat_input(struct dlm_write_request *kb, | |
83 | struct dlm_write_request32 *kb32) | |
84 | { | |
85 | kb->version[0] = kb32->version[0]; | |
86 | kb->version[1] = kb32->version[1]; | |
87 | kb->version[2] = kb32->version[2]; | |
88 | ||
89 | kb->cmd = kb32->cmd; | |
90 | kb->is64bit = kb32->is64bit; | |
91 | if (kb->cmd == DLM_USER_CREATE_LOCKSPACE || | |
92 | kb->cmd == DLM_USER_REMOVE_LOCKSPACE) { | |
93 | kb->i.lspace.flags = kb32->i.lspace.flags; | |
94 | kb->i.lspace.minor = kb32->i.lspace.minor; | |
95 | strcpy(kb->i.lspace.name, kb32->i.lspace.name); | |
72c2be77 DT |
96 | } else if (kb->cmd == DLM_USER_PURGE) { |
97 | kb->i.purge.nodeid = kb32->i.purge.nodeid; | |
98 | kb->i.purge.pid = kb32->i.purge.pid; | |
597d0cae DT |
99 | } else { |
100 | kb->i.lock.mode = kb32->i.lock.mode; | |
101 | kb->i.lock.namelen = kb32->i.lock.namelen; | |
102 | kb->i.lock.flags = kb32->i.lock.flags; | |
103 | kb->i.lock.lkid = kb32->i.lock.lkid; | |
104 | kb->i.lock.parent = kb32->i.lock.parent; | |
105 | kb->i.lock.castparam = (void *)(long)kb32->i.lock.castparam; | |
106 | kb->i.lock.castaddr = (void *)(long)kb32->i.lock.castaddr; | |
107 | kb->i.lock.bastparam = (void *)(long)kb32->i.lock.bastparam; | |
108 | kb->i.lock.bastaddr = (void *)(long)kb32->i.lock.bastaddr; | |
109 | kb->i.lock.lksb = (void *)(long)kb32->i.lock.lksb; | |
110 | memcpy(kb->i.lock.lvb, kb32->i.lock.lvb, DLM_USER_LVB_LEN); | |
111 | memcpy(kb->i.lock.name, kb32->i.lock.name, kb->i.lock.namelen); | |
112 | } | |
113 | } | |
114 | ||
115 | static void compat_output(struct dlm_lock_result *res, | |
116 | struct dlm_lock_result32 *res32) | |
117 | { | |
597d0cae DT |
118 | res32->user_astaddr = (__u32)(long)res->user_astaddr; |
119 | res32->user_astparam = (__u32)(long)res->user_astparam; | |
120 | res32->user_lksb = (__u32)(long)res->user_lksb; | |
121 | res32->bast_mode = res->bast_mode; | |
122 | ||
123 | res32->lvb_offset = res->lvb_offset; | |
124 | res32->length = res->length; | |
125 | ||
126 | res32->lksb.sb_status = res->lksb.sb_status; | |
127 | res32->lksb.sb_flags = res->lksb.sb_flags; | |
128 | res32->lksb.sb_lkid = res->lksb.sb_lkid; | |
129 | res32->lksb.sb_lvbptr = (__u32)(long)res->lksb.sb_lvbptr; | |
130 | } | |
131 | #endif | |
132 | ||
ef0c2bb0 DT |
133 | /* we could possibly check if the cancel of an orphan has resulted in the lkb |
134 | being removed and then remove that lkb from the orphans list and free it */ | |
597d0cae DT |
135 | |
136 | void dlm_user_add_ast(struct dlm_lkb *lkb, int type) | |
137 | { | |
138 | struct dlm_ls *ls; | |
139 | struct dlm_user_args *ua; | |
140 | struct dlm_user_proc *proc; | |
ef0c2bb0 | 141 | int eol = 0, ast_type; |
597d0cae | 142 | |
ef0c2bb0 | 143 | if (lkb->lkb_flags & (DLM_IFL_ORPHAN | DLM_IFL_DEAD)) |
597d0cae | 144 | return; |
597d0cae DT |
145 | |
146 | ls = lkb->lkb_resource->res_ls; | |
147 | mutex_lock(&ls->ls_clear_proc_locks); | |
148 | ||
149 | /* If ORPHAN/DEAD flag is set, it means the process is dead so an ast | |
150 | can't be delivered. For ORPHAN's, dlm_clear_proc_locks() freed | |
ef0c2bb0 DT |
151 | lkb->ua so we can't try to use it. This second check is necessary |
152 | for cases where a completion ast is received for an operation that | |
153 | began before clear_proc_locks did its cancel/unlock. */ | |
597d0cae | 154 | |
ef0c2bb0 | 155 | if (lkb->lkb_flags & (DLM_IFL_ORPHAN | DLM_IFL_DEAD)) |
597d0cae | 156 | goto out; |
597d0cae DT |
157 | |
158 | DLM_ASSERT(lkb->lkb_astparam, dlm_print_lkb(lkb);); | |
159 | ua = (struct dlm_user_args *)lkb->lkb_astparam; | |
160 | proc = ua->proc; | |
161 | ||
162 | if (type == AST_BAST && ua->bastaddr == NULL) | |
163 | goto out; | |
164 | ||
165 | spin_lock(&proc->asts_spin); | |
ef0c2bb0 DT |
166 | |
167 | ast_type = lkb->lkb_ast_type; | |
168 | lkb->lkb_ast_type |= type; | |
169 | ||
170 | if (!ast_type) { | |
597d0cae DT |
171 | kref_get(&lkb->lkb_ref); |
172 | list_add_tail(&lkb->lkb_astqueue, &proc->asts); | |
597d0cae DT |
173 | wake_up_interruptible(&proc->wait); |
174 | } | |
ef0c2bb0 DT |
175 | if (type == AST_COMP && (ast_type & AST_COMP)) |
176 | log_debug(ls, "ast overlap %x status %x %x", | |
177 | lkb->lkb_id, ua->lksb.sb_status, lkb->lkb_flags); | |
178 | ||
179 | /* Figure out if this lock is at the end of its life and no longer | |
180 | available for the application to use. The lkb still exists until | |
181 | the final ast is read. A lock becomes EOL in three situations: | |
182 | 1. a noqueue request fails with EAGAIN | |
183 | 2. an unlock completes with EUNLOCK | |
184 | 3. a cancel of a waiting request completes with ECANCEL | |
185 | An EOL lock needs to be removed from the process's list of locks. | |
186 | And we can't allow any new operation on an EOL lock. This is | |
187 | not related to the lifetime of the lkb struct which is managed | |
188 | entirely by refcount. */ | |
189 | ||
190 | if (type == AST_COMP && | |
191 | lkb->lkb_grmode == DLM_LOCK_IV && | |
192 | ua->lksb.sb_status == -EAGAIN) | |
193 | eol = 1; | |
194 | else if (ua->lksb.sb_status == -DLM_EUNLOCK || | |
a1bc86e6 DT |
195 | (ua->lksb.sb_status == -DLM_ECANCEL && |
196 | lkb->lkb_grmode == DLM_LOCK_IV)) | |
ef0c2bb0 DT |
197 | eol = 1; |
198 | if (eol) { | |
199 | lkb->lkb_ast_type &= ~AST_BAST; | |
200 | lkb->lkb_flags |= DLM_IFL_ENDOFLIFE; | |
201 | } | |
a1bc86e6 | 202 | |
597d0cae DT |
203 | /* We want to copy the lvb to userspace when the completion |
204 | ast is read if the status is 0, the lock has an lvb and | |
205 | lvb_ops says we should. We could probably have set_lvb_lock() | |
206 | set update_user_lvb instead and not need old_mode */ | |
207 | ||
208 | if ((lkb->lkb_ast_type & AST_COMP) && | |
209 | (lkb->lkb_lksb->sb_status == 0) && | |
210 | lkb->lkb_lksb->sb_lvbptr && | |
211 | dlm_lvb_operations[ua->old_mode + 1][lkb->lkb_grmode + 1]) | |
212 | ua->update_user_lvb = 1; | |
213 | else | |
214 | ua->update_user_lvb = 0; | |
215 | ||
216 | spin_unlock(&proc->asts_spin); | |
34e22bed | 217 | |
ef0c2bb0 | 218 | if (eol) { |
34e22bed | 219 | spin_lock(&ua->proc->locks_spin); |
ef0c2bb0 DT |
220 | if (!list_empty(&lkb->lkb_ownqueue)) { |
221 | list_del_init(&lkb->lkb_ownqueue); | |
222 | dlm_put_lkb(lkb); | |
223 | } | |
34e22bed | 224 | spin_unlock(&ua->proc->locks_spin); |
34e22bed | 225 | } |
597d0cae DT |
226 | out: |
227 | mutex_unlock(&ls->ls_clear_proc_locks); | |
228 | } | |
229 | ||
230 | static int device_user_lock(struct dlm_user_proc *proc, | |
231 | struct dlm_lock_params *params) | |
232 | { | |
233 | struct dlm_ls *ls; | |
234 | struct dlm_user_args *ua; | |
235 | int error = -ENOMEM; | |
236 | ||
237 | ls = dlm_find_lockspace_local(proc->lockspace); | |
238 | if (!ls) | |
239 | return -ENOENT; | |
240 | ||
241 | if (!params->castaddr || !params->lksb) { | |
242 | error = -EINVAL; | |
243 | goto out; | |
244 | } | |
245 | ||
246 | ua = kzalloc(sizeof(struct dlm_user_args), GFP_KERNEL); | |
247 | if (!ua) | |
248 | goto out; | |
249 | ua->proc = proc; | |
250 | ua->user_lksb = params->lksb; | |
251 | ua->castparam = params->castparam; | |
252 | ua->castaddr = params->castaddr; | |
253 | ua->bastparam = params->bastparam; | |
254 | ua->bastaddr = params->bastaddr; | |
255 | ||
256 | if (params->flags & DLM_LKF_CONVERT) | |
257 | error = dlm_user_convert(ls, ua, | |
258 | params->mode, params->flags, | |
259 | params->lkid, params->lvb); | |
260 | else { | |
261 | error = dlm_user_request(ls, ua, | |
262 | params->mode, params->flags, | |
263 | params->name, params->namelen, | |
264 | params->parent); | |
265 | if (!error) | |
266 | error = ua->lksb.sb_lkid; | |
267 | } | |
268 | out: | |
269 | dlm_put_lockspace(ls); | |
270 | return error; | |
271 | } | |
272 | ||
273 | static int device_user_unlock(struct dlm_user_proc *proc, | |
274 | struct dlm_lock_params *params) | |
275 | { | |
276 | struct dlm_ls *ls; | |
277 | struct dlm_user_args *ua; | |
278 | int error = -ENOMEM; | |
279 | ||
280 | ls = dlm_find_lockspace_local(proc->lockspace); | |
281 | if (!ls) | |
282 | return -ENOENT; | |
283 | ||
284 | ua = kzalloc(sizeof(struct dlm_user_args), GFP_KERNEL); | |
285 | if (!ua) | |
286 | goto out; | |
287 | ua->proc = proc; | |
288 | ua->user_lksb = params->lksb; | |
289 | ua->castparam = params->castparam; | |
290 | ua->castaddr = params->castaddr; | |
291 | ||
292 | if (params->flags & DLM_LKF_CANCEL) | |
293 | error = dlm_user_cancel(ls, ua, params->flags, params->lkid); | |
294 | else | |
295 | error = dlm_user_unlock(ls, ua, params->flags, params->lkid, | |
296 | params->lvb); | |
297 | out: | |
298 | dlm_put_lockspace(ls); | |
299 | return error; | |
300 | } | |
301 | ||
254da030 PC |
302 | static int create_misc_device(struct dlm_ls *ls, char *name) |
303 | { | |
304 | int error, len; | |
305 | ||
306 | error = -ENOMEM; | |
307 | len = strlen(name) + strlen(name_prefix) + 2; | |
308 | ls->ls_device.name = kzalloc(len, GFP_KERNEL); | |
309 | if (!ls->ls_device.name) | |
310 | goto fail; | |
311 | ||
312 | snprintf((char *)ls->ls_device.name, len, "%s_%s", name_prefix, | |
313 | name); | |
314 | ls->ls_device.fops = &device_fops; | |
315 | ls->ls_device.minor = MISC_DYNAMIC_MINOR; | |
316 | ||
317 | error = misc_register(&ls->ls_device); | |
318 | if (error) { | |
319 | kfree(ls->ls_device.name); | |
320 | } | |
321 | fail: | |
322 | return error; | |
323 | } | |
324 | ||
72c2be77 DT |
325 | static int device_user_purge(struct dlm_user_proc *proc, |
326 | struct dlm_purge_params *params) | |
327 | { | |
328 | struct dlm_ls *ls; | |
329 | int error; | |
330 | ||
331 | ls = dlm_find_lockspace_local(proc->lockspace); | |
332 | if (!ls) | |
333 | return -ENOENT; | |
334 | ||
335 | error = dlm_user_purge(ls, proc, params->nodeid, params->pid); | |
336 | ||
337 | dlm_put_lockspace(ls); | |
338 | return error; | |
339 | } | |
340 | ||
597d0cae DT |
341 | static int device_create_lockspace(struct dlm_lspace_params *params) |
342 | { | |
343 | dlm_lockspace_t *lockspace; | |
344 | struct dlm_ls *ls; | |
254da030 | 345 | int error; |
597d0cae DT |
346 | |
347 | if (!capable(CAP_SYS_ADMIN)) | |
348 | return -EPERM; | |
349 | ||
350 | error = dlm_new_lockspace(params->name, strlen(params->name), | |
3ae1acf9 | 351 | &lockspace, params->flags, DLM_USER_LVB_LEN); |
597d0cae DT |
352 | if (error) |
353 | return error; | |
354 | ||
355 | ls = dlm_find_lockspace_local(lockspace); | |
356 | if (!ls) | |
357 | return -ENOENT; | |
358 | ||
254da030 | 359 | error = create_misc_device(ls, params->name); |
597d0cae | 360 | dlm_put_lockspace(ls); |
597d0cae | 361 | |
254da030 PC |
362 | if (error) |
363 | dlm_release_lockspace(lockspace, 0); | |
364 | else | |
365 | error = ls->ls_device.minor; | |
366 | ||
597d0cae DT |
367 | return error; |
368 | } | |
369 | ||
370 | static int device_remove_lockspace(struct dlm_lspace_params *params) | |
371 | { | |
372 | dlm_lockspace_t *lockspace; | |
373 | struct dlm_ls *ls; | |
c6e6f0ba | 374 | int error, force = 0; |
597d0cae DT |
375 | |
376 | if (!capable(CAP_SYS_ADMIN)) | |
377 | return -EPERM; | |
378 | ||
379 | ls = dlm_find_lockspace_device(params->minor); | |
380 | if (!ls) | |
381 | return -ENOENT; | |
382 | ||
254da030 PC |
383 | /* Deregister the misc device first, so we don't have |
384 | * a device that's not attached to a lockspace. If | |
385 | * dlm_release_lockspace fails then we can recreate it | |
386 | */ | |
597d0cae DT |
387 | error = misc_deregister(&ls->ls_device); |
388 | if (error) { | |
389 | dlm_put_lockspace(ls); | |
390 | goto out; | |
391 | } | |
392 | kfree(ls->ls_device.name); | |
393 | ||
c6e6f0ba DT |
394 | if (params->flags & DLM_USER_LSFLG_FORCEFREE) |
395 | force = 2; | |
396 | ||
597d0cae DT |
397 | lockspace = ls->ls_local_handle; |
398 | ||
399 | /* dlm_release_lockspace waits for references to go to zero, | |
400 | so all processes will need to close their device for the ls | |
401 | before the release will procede */ | |
402 | ||
403 | dlm_put_lockspace(ls); | |
c6e6f0ba | 404 | error = dlm_release_lockspace(lockspace, force); |
254da030 PC |
405 | if (error) |
406 | create_misc_device(ls, ls->ls_name); | |
c6e6f0ba | 407 | out: |
597d0cae DT |
408 | return error; |
409 | } | |
410 | ||
411 | /* Check the user's version matches ours */ | |
412 | static int check_version(struct dlm_write_request *req) | |
413 | { | |
414 | if (req->version[0] != DLM_DEVICE_VERSION_MAJOR || | |
415 | (req->version[0] == DLM_DEVICE_VERSION_MAJOR && | |
416 | req->version[1] > DLM_DEVICE_VERSION_MINOR)) { | |
417 | ||
418 | printk(KERN_DEBUG "dlm: process %s (%d) version mismatch " | |
419 | "user (%d.%d.%d) kernel (%d.%d.%d)\n", | |
420 | current->comm, | |
421 | current->pid, | |
422 | req->version[0], | |
423 | req->version[1], | |
424 | req->version[2], | |
425 | DLM_DEVICE_VERSION_MAJOR, | |
426 | DLM_DEVICE_VERSION_MINOR, | |
427 | DLM_DEVICE_VERSION_PATCH); | |
428 | return -EINVAL; | |
429 | } | |
430 | return 0; | |
431 | } | |
432 | ||
433 | /* | |
434 | * device_write | |
435 | * | |
436 | * device_user_lock | |
437 | * dlm_user_request -> request_lock | |
438 | * dlm_user_convert -> convert_lock | |
439 | * | |
440 | * device_user_unlock | |
441 | * dlm_user_unlock -> unlock_lock | |
442 | * dlm_user_cancel -> cancel_lock | |
443 | * | |
444 | * device_create_lockspace | |
445 | * dlm_new_lockspace | |
446 | * | |
447 | * device_remove_lockspace | |
448 | * dlm_release_lockspace | |
449 | */ | |
450 | ||
451 | /* a write to a lockspace device is a lock or unlock request, a write | |
452 | to the control device is to create/remove a lockspace */ | |
453 | ||
454 | static ssize_t device_write(struct file *file, const char __user *buf, | |
455 | size_t count, loff_t *ppos) | |
456 | { | |
457 | struct dlm_user_proc *proc = file->private_data; | |
458 | struct dlm_write_request *kbuf; | |
459 | sigset_t tmpsig, allsigs; | |
460 | int error; | |
461 | ||
462 | #ifdef CONFIG_COMPAT | |
463 | if (count < sizeof(struct dlm_write_request32)) | |
464 | #else | |
465 | if (count < sizeof(struct dlm_write_request)) | |
466 | #endif | |
467 | return -EINVAL; | |
468 | ||
469 | kbuf = kmalloc(count, GFP_KERNEL); | |
470 | if (!kbuf) | |
471 | return -ENOMEM; | |
472 | ||
473 | if (copy_from_user(kbuf, buf, count)) { | |
474 | error = -EFAULT; | |
475 | goto out_free; | |
476 | } | |
477 | ||
478 | if (check_version(kbuf)) { | |
479 | error = -EBADE; | |
480 | goto out_free; | |
481 | } | |
482 | ||
483 | #ifdef CONFIG_COMPAT | |
484 | if (!kbuf->is64bit) { | |
485 | struct dlm_write_request32 *k32buf; | |
486 | k32buf = (struct dlm_write_request32 *)kbuf; | |
487 | kbuf = kmalloc(count + (sizeof(struct dlm_write_request) - | |
488 | sizeof(struct dlm_write_request32)), GFP_KERNEL); | |
489 | if (!kbuf) | |
490 | return -ENOMEM; | |
491 | ||
492 | if (proc) | |
493 | set_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags); | |
494 | compat_input(kbuf, k32buf); | |
495 | kfree(k32buf); | |
496 | } | |
497 | #endif | |
498 | ||
499 | /* do we really need this? can a write happen after a close? */ | |
500 | if ((kbuf->cmd == DLM_USER_LOCK || kbuf->cmd == DLM_USER_UNLOCK) && | |
501 | test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags)) | |
502 | return -EINVAL; | |
503 | ||
504 | sigfillset(&allsigs); | |
505 | sigprocmask(SIG_BLOCK, &allsigs, &tmpsig); | |
506 | ||
507 | error = -EINVAL; | |
508 | ||
509 | switch (kbuf->cmd) | |
510 | { | |
511 | case DLM_USER_LOCK: | |
512 | if (!proc) { | |
513 | log_print("no locking on control device"); | |
514 | goto out_sig; | |
515 | } | |
516 | error = device_user_lock(proc, &kbuf->i.lock); | |
517 | break; | |
518 | ||
519 | case DLM_USER_UNLOCK: | |
520 | if (!proc) { | |
521 | log_print("no locking on control device"); | |
522 | goto out_sig; | |
523 | } | |
524 | error = device_user_unlock(proc, &kbuf->i.lock); | |
525 | break; | |
526 | ||
527 | case DLM_USER_CREATE_LOCKSPACE: | |
528 | if (proc) { | |
529 | log_print("create/remove only on control device"); | |
530 | goto out_sig; | |
531 | } | |
532 | error = device_create_lockspace(&kbuf->i.lspace); | |
533 | break; | |
534 | ||
535 | case DLM_USER_REMOVE_LOCKSPACE: | |
536 | if (proc) { | |
537 | log_print("create/remove only on control device"); | |
538 | goto out_sig; | |
539 | } | |
540 | error = device_remove_lockspace(&kbuf->i.lspace); | |
541 | break; | |
542 | ||
72c2be77 DT |
543 | case DLM_USER_PURGE: |
544 | if (!proc) { | |
545 | log_print("no locking on control device"); | |
546 | goto out_sig; | |
547 | } | |
548 | error = device_user_purge(proc, &kbuf->i.purge); | |
549 | break; | |
550 | ||
597d0cae DT |
551 | default: |
552 | log_print("Unknown command passed to DLM device : %d\n", | |
553 | kbuf->cmd); | |
554 | } | |
555 | ||
556 | out_sig: | |
557 | sigprocmask(SIG_SETMASK, &tmpsig, NULL); | |
558 | recalc_sigpending(); | |
559 | out_free: | |
560 | kfree(kbuf); | |
561 | return error; | |
562 | } | |
563 | ||
564 | /* Every process that opens the lockspace device has its own "proc" structure | |
565 | hanging off the open file that's used to keep track of locks owned by the | |
566 | process and asts that need to be delivered to the process. */ | |
567 | ||
568 | static int device_open(struct inode *inode, struct file *file) | |
569 | { | |
570 | struct dlm_user_proc *proc; | |
571 | struct dlm_ls *ls; | |
572 | ||
573 | ls = dlm_find_lockspace_device(iminor(inode)); | |
574 | if (!ls) | |
575 | return -ENOENT; | |
576 | ||
577 | proc = kzalloc(sizeof(struct dlm_user_proc), GFP_KERNEL); | |
578 | if (!proc) { | |
579 | dlm_put_lockspace(ls); | |
580 | return -ENOMEM; | |
581 | } | |
582 | ||
583 | proc->lockspace = ls->ls_local_handle; | |
584 | INIT_LIST_HEAD(&proc->asts); | |
585 | INIT_LIST_HEAD(&proc->locks); | |
a1bc86e6 | 586 | INIT_LIST_HEAD(&proc->unlocking); |
597d0cae DT |
587 | spin_lock_init(&proc->asts_spin); |
588 | spin_lock_init(&proc->locks_spin); | |
589 | init_waitqueue_head(&proc->wait); | |
590 | file->private_data = proc; | |
591 | ||
592 | return 0; | |
593 | } | |
594 | ||
595 | static int device_close(struct inode *inode, struct file *file) | |
596 | { | |
597 | struct dlm_user_proc *proc = file->private_data; | |
598 | struct dlm_ls *ls; | |
599 | sigset_t tmpsig, allsigs; | |
600 | ||
601 | ls = dlm_find_lockspace_local(proc->lockspace); | |
602 | if (!ls) | |
603 | return -ENOENT; | |
604 | ||
605 | sigfillset(&allsigs); | |
606 | sigprocmask(SIG_BLOCK, &allsigs, &tmpsig); | |
607 | ||
608 | set_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags); | |
609 | ||
610 | dlm_clear_proc_locks(ls, proc); | |
611 | ||
612 | /* at this point no more lkb's should exist for this lockspace, | |
613 | so there's no chance of dlm_user_add_ast() being called and | |
614 | looking for lkb->ua->proc */ | |
615 | ||
616 | kfree(proc); | |
617 | file->private_data = NULL; | |
618 | ||
619 | dlm_put_lockspace(ls); | |
620 | dlm_put_lockspace(ls); /* for the find in device_open() */ | |
621 | ||
622 | /* FIXME: AUTOFREE: if this ls is no longer used do | |
623 | device_remove_lockspace() */ | |
624 | ||
625 | sigprocmask(SIG_SETMASK, &tmpsig, NULL); | |
626 | recalc_sigpending(); | |
627 | ||
628 | return 0; | |
629 | } | |
630 | ||
631 | static int copy_result_to_user(struct dlm_user_args *ua, int compat, int type, | |
632 | int bmode, char __user *buf, size_t count) | |
633 | { | |
634 | #ifdef CONFIG_COMPAT | |
635 | struct dlm_lock_result32 result32; | |
636 | #endif | |
637 | struct dlm_lock_result result; | |
638 | void *resultptr; | |
639 | int error=0; | |
640 | int len; | |
641 | int struct_len; | |
642 | ||
643 | memset(&result, 0, sizeof(struct dlm_lock_result)); | |
644 | memcpy(&result.lksb, &ua->lksb, sizeof(struct dlm_lksb)); | |
645 | result.user_lksb = ua->user_lksb; | |
646 | ||
647 | /* FIXME: dlm1 provides for the user's bastparam/addr to not be updated | |
648 | in a conversion unless the conversion is successful. See code | |
649 | in dlm_user_convert() for updating ua from ua_tmp. OpenVMS, though, | |
650 | notes that a new blocking AST address and parameter are set even if | |
651 | the conversion fails, so maybe we should just do that. */ | |
652 | ||
653 | if (type == AST_BAST) { | |
654 | result.user_astaddr = ua->bastaddr; | |
655 | result.user_astparam = ua->bastparam; | |
656 | result.bast_mode = bmode; | |
657 | } else { | |
658 | result.user_astaddr = ua->castaddr; | |
659 | result.user_astparam = ua->castparam; | |
660 | } | |
661 | ||
662 | #ifdef CONFIG_COMPAT | |
663 | if (compat) | |
664 | len = sizeof(struct dlm_lock_result32); | |
665 | else | |
666 | #endif | |
667 | len = sizeof(struct dlm_lock_result); | |
668 | struct_len = len; | |
669 | ||
670 | /* copy lvb to userspace if there is one, it's been updated, and | |
671 | the user buffer has space for it */ | |
672 | ||
673 | if (ua->update_user_lvb && ua->lksb.sb_lvbptr && | |
674 | count >= len + DLM_USER_LVB_LEN) { | |
675 | if (copy_to_user(buf+len, ua->lksb.sb_lvbptr, | |
676 | DLM_USER_LVB_LEN)) { | |
677 | error = -EFAULT; | |
678 | goto out; | |
679 | } | |
680 | ||
681 | result.lvb_offset = len; | |
682 | len += DLM_USER_LVB_LEN; | |
683 | } | |
684 | ||
685 | result.length = len; | |
686 | resultptr = &result; | |
687 | #ifdef CONFIG_COMPAT | |
688 | if (compat) { | |
689 | compat_output(&result, &result32); | |
690 | resultptr = &result32; | |
691 | } | |
692 | #endif | |
693 | ||
694 | if (copy_to_user(buf, resultptr, struct_len)) | |
695 | error = -EFAULT; | |
696 | else | |
697 | error = len; | |
698 | out: | |
699 | return error; | |
700 | } | |
701 | ||
702 | /* a read returns a single ast described in a struct dlm_lock_result */ | |
703 | ||
704 | static ssize_t device_read(struct file *file, char __user *buf, size_t count, | |
705 | loff_t *ppos) | |
706 | { | |
707 | struct dlm_user_proc *proc = file->private_data; | |
708 | struct dlm_lkb *lkb; | |
709 | struct dlm_user_args *ua; | |
710 | DECLARE_WAITQUEUE(wait, current); | |
711 | int error, type=0, bmode=0, removed = 0; | |
712 | ||
713 | #ifdef CONFIG_COMPAT | |
714 | if (count < sizeof(struct dlm_lock_result32)) | |
715 | #else | |
716 | if (count < sizeof(struct dlm_lock_result)) | |
717 | #endif | |
718 | return -EINVAL; | |
719 | ||
720 | /* do we really need this? can a read happen after a close? */ | |
721 | if (test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags)) | |
722 | return -EINVAL; | |
723 | ||
724 | spin_lock(&proc->asts_spin); | |
725 | if (list_empty(&proc->asts)) { | |
726 | if (file->f_flags & O_NONBLOCK) { | |
727 | spin_unlock(&proc->asts_spin); | |
728 | return -EAGAIN; | |
729 | } | |
730 | ||
731 | add_wait_queue(&proc->wait, &wait); | |
732 | ||
733 | repeat: | |
734 | set_current_state(TASK_INTERRUPTIBLE); | |
735 | if (list_empty(&proc->asts) && !signal_pending(current)) { | |
736 | spin_unlock(&proc->asts_spin); | |
737 | schedule(); | |
738 | spin_lock(&proc->asts_spin); | |
739 | goto repeat; | |
740 | } | |
741 | set_current_state(TASK_RUNNING); | |
742 | remove_wait_queue(&proc->wait, &wait); | |
743 | ||
744 | if (signal_pending(current)) { | |
745 | spin_unlock(&proc->asts_spin); | |
746 | return -ERESTARTSYS; | |
747 | } | |
748 | } | |
749 | ||
750 | if (list_empty(&proc->asts)) { | |
751 | spin_unlock(&proc->asts_spin); | |
752 | return -EAGAIN; | |
753 | } | |
754 | ||
755 | /* there may be both completion and blocking asts to return for | |
756 | the lkb, don't remove lkb from asts list unless no asts remain */ | |
757 | ||
758 | lkb = list_entry(proc->asts.next, struct dlm_lkb, lkb_astqueue); | |
759 | ||
760 | if (lkb->lkb_ast_type & AST_COMP) { | |
761 | lkb->lkb_ast_type &= ~AST_COMP; | |
762 | type = AST_COMP; | |
763 | } else if (lkb->lkb_ast_type & AST_BAST) { | |
764 | lkb->lkb_ast_type &= ~AST_BAST; | |
765 | type = AST_BAST; | |
766 | bmode = lkb->lkb_bastmode; | |
767 | } | |
768 | ||
769 | if (!lkb->lkb_ast_type) { | |
770 | list_del(&lkb->lkb_astqueue); | |
771 | removed = 1; | |
772 | } | |
773 | spin_unlock(&proc->asts_spin); | |
774 | ||
775 | ua = (struct dlm_user_args *)lkb->lkb_astparam; | |
776 | error = copy_result_to_user(ua, | |
777 | test_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags), | |
778 | type, bmode, buf, count); | |
779 | ||
780 | /* removes reference for the proc->asts lists added by | |
781 | dlm_user_add_ast() and may result in the lkb being freed */ | |
782 | if (removed) | |
783 | dlm_put_lkb(lkb); | |
784 | ||
785 | return error; | |
786 | } | |
787 | ||
788 | static unsigned int device_poll(struct file *file, poll_table *wait) | |
789 | { | |
790 | struct dlm_user_proc *proc = file->private_data; | |
791 | ||
792 | poll_wait(file, &proc->wait, wait); | |
793 | ||
794 | spin_lock(&proc->asts_spin); | |
795 | if (!list_empty(&proc->asts)) { | |
796 | spin_unlock(&proc->asts_spin); | |
797 | return POLLIN | POLLRDNORM; | |
798 | } | |
799 | spin_unlock(&proc->asts_spin); | |
800 | return 0; | |
801 | } | |
802 | ||
803 | static int ctl_device_open(struct inode *inode, struct file *file) | |
804 | { | |
805 | file->private_data = NULL; | |
806 | return 0; | |
807 | } | |
808 | ||
809 | static int ctl_device_close(struct inode *inode, struct file *file) | |
810 | { | |
811 | return 0; | |
812 | } | |
813 | ||
00977a59 | 814 | static const struct file_operations device_fops = { |
597d0cae DT |
815 | .open = device_open, |
816 | .release = device_close, | |
817 | .read = device_read, | |
818 | .write = device_write, | |
819 | .poll = device_poll, | |
820 | .owner = THIS_MODULE, | |
821 | }; | |
822 | ||
00977a59 | 823 | static const struct file_operations ctl_device_fops = { |
597d0cae DT |
824 | .open = ctl_device_open, |
825 | .release = ctl_device_close, | |
826 | .write = device_write, | |
827 | .owner = THIS_MODULE, | |
828 | }; | |
829 | ||
830 | int dlm_user_init(void) | |
831 | { | |
832 | int error; | |
833 | ||
834 | ctl_device.name = "dlm-control"; | |
835 | ctl_device.fops = &ctl_device_fops; | |
836 | ctl_device.minor = MISC_DYNAMIC_MINOR; | |
837 | ||
838 | error = misc_register(&ctl_device); | |
839 | if (error) | |
840 | log_print("misc_register failed for control device"); | |
841 | ||
842 | return error; | |
843 | } | |
844 | ||
845 | void dlm_user_exit(void) | |
846 | { | |
847 | misc_deregister(&ctl_device); | |
848 | } | |
849 |