Commit | Line | Data |
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b3b94faa DT |
1 | /* |
2 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
3a8a9a10 | 3 | * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. |
b3b94faa DT |
4 | * |
5 | * This copyrighted material is made available to anyone wishing to use, | |
6 | * modify, copy, or redistribute it subject to the terms and conditions | |
e9fc2aa0 | 7 | * of the GNU General Public License version 2. |
b3b94faa DT |
8 | */ |
9 | ||
10 | #include <linux/sched.h> | |
11 | #include <linux/slab.h> | |
12 | #include <linux/spinlock.h> | |
13 | #include <linux/completion.h> | |
14 | #include <linux/buffer_head.h> | |
15 | #include <linux/delay.h> | |
16 | #include <linux/sort.h> | |
17 | #include <linux/jhash.h> | |
d0dc80db | 18 | #include <linux/kallsyms.h> |
5c676f6d | 19 | #include <linux/gfs2_ondisk.h> |
24264434 | 20 | #include <linux/list.h> |
7d308590 | 21 | #include <linux/lm_interface.h> |
fee852e3 | 22 | #include <linux/wait.h> |
95d97b7d | 23 | #include <linux/module.h> |
61be084e | 24 | #include <linux/rwsem.h> |
b3b94faa | 25 | #include <asm/uaccess.h> |
7c52b166 RP |
26 | #include <linux/seq_file.h> |
27 | #include <linux/debugfs.h> | |
b3b94faa DT |
28 | |
29 | #include "gfs2.h" | |
5c676f6d | 30 | #include "incore.h" |
b3b94faa DT |
31 | #include "glock.h" |
32 | #include "glops.h" | |
33 | #include "inode.h" | |
34 | #include "lm.h" | |
35 | #include "lops.h" | |
36 | #include "meta_io.h" | |
37 | #include "quota.h" | |
38 | #include "super.h" | |
5c676f6d | 39 | #include "util.h" |
b3b94faa | 40 | |
37b2fa6a | 41 | struct gfs2_gl_hash_bucket { |
b6397893 | 42 | struct hlist_head hb_list; |
37b2fa6a SW |
43 | }; |
44 | ||
7c52b166 RP |
45 | struct glock_iter { |
46 | int hash; /* hash bucket index */ | |
47 | struct gfs2_sbd *sdp; /* incore superblock */ | |
48 | struct gfs2_glock *gl; /* current glock struct */ | |
49 | struct hlist_head *hb_list; /* current hash bucket ptr */ | |
50 | struct seq_file *seq; /* sequence file for debugfs */ | |
51 | char string[512]; /* scratch space */ | |
52 | }; | |
53 | ||
b3b94faa DT |
54 | typedef void (*glock_examiner) (struct gfs2_glock * gl); |
55 | ||
08bc2dbc | 56 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp); |
b5d32bea SW |
57 | static void gfs2_glock_xmote_th(struct gfs2_holder *gh); |
58 | static void gfs2_glock_drop_th(struct gfs2_glock *gl); | |
61be084e | 59 | static DECLARE_RWSEM(gfs2_umount_flush_sem); |
7c52b166 | 60 | static struct dentry *gfs2_root; |
08bc2dbc | 61 | |
b6397893 | 62 | #define GFS2_GL_HASH_SHIFT 15 |
087efdd3 SW |
63 | #define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT) |
64 | #define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1) | |
65 | ||
85d1da67 | 66 | static struct gfs2_gl_hash_bucket gl_hash_table[GFS2_GL_HASH_SIZE]; |
087efdd3 SW |
67 | |
68 | /* | |
69 | * Despite what you might think, the numbers below are not arbitrary :-) | |
70 | * They are taken from the ipv4 routing hash code, which is well tested | |
71 | * and thus should be nearly optimal. Later on we might tweek the numbers | |
72 | * but for now this should be fine. | |
73 | * | |
74 | * The reason for putting the locks in a separate array from the list heads | |
75 | * is that we can have fewer locks than list heads and save memory. We use | |
76 | * the same hash function for both, but with a different hash mask. | |
77 | */ | |
78 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \ | |
79 | defined(CONFIG_PROVE_LOCKING) | |
80 | ||
81 | #ifdef CONFIG_LOCKDEP | |
82 | # define GL_HASH_LOCK_SZ 256 | |
83 | #else | |
84 | # if NR_CPUS >= 32 | |
85 | # define GL_HASH_LOCK_SZ 4096 | |
86 | # elif NR_CPUS >= 16 | |
87 | # define GL_HASH_LOCK_SZ 2048 | |
88 | # elif NR_CPUS >= 8 | |
89 | # define GL_HASH_LOCK_SZ 1024 | |
90 | # elif NR_CPUS >= 4 | |
91 | # define GL_HASH_LOCK_SZ 512 | |
92 | # else | |
93 | # define GL_HASH_LOCK_SZ 256 | |
94 | # endif | |
95 | #endif | |
96 | ||
97 | /* We never want more locks than chains */ | |
98 | #if GFS2_GL_HASH_SIZE < GL_HASH_LOCK_SZ | |
99 | # undef GL_HASH_LOCK_SZ | |
100 | # define GL_HASH_LOCK_SZ GFS2_GL_HASH_SIZE | |
101 | #endif | |
102 | ||
103 | static rwlock_t gl_hash_locks[GL_HASH_LOCK_SZ]; | |
104 | ||
105 | static inline rwlock_t *gl_lock_addr(unsigned int x) | |
106 | { | |
94610610 | 107 | return &gl_hash_locks[x & (GL_HASH_LOCK_SZ-1)]; |
087efdd3 SW |
108 | } |
109 | #else /* not SMP, so no spinlocks required */ | |
0ac23069 | 110 | static inline rwlock_t *gl_lock_addr(unsigned int x) |
087efdd3 SW |
111 | { |
112 | return NULL; | |
113 | } | |
114 | #endif | |
85d1da67 | 115 | |
b3b94faa DT |
116 | /** |
117 | * relaxed_state_ok - is a requested lock compatible with the current lock mode? | |
118 | * @actual: the current state of the lock | |
119 | * @requested: the lock state that was requested by the caller | |
120 | * @flags: the modifier flags passed in by the caller | |
121 | * | |
122 | * Returns: 1 if the locks are compatible, 0 otherwise | |
123 | */ | |
124 | ||
125 | static inline int relaxed_state_ok(unsigned int actual, unsigned requested, | |
126 | int flags) | |
127 | { | |
128 | if (actual == requested) | |
129 | return 1; | |
130 | ||
131 | if (flags & GL_EXACT) | |
132 | return 0; | |
133 | ||
134 | if (actual == LM_ST_EXCLUSIVE && requested == LM_ST_SHARED) | |
135 | return 1; | |
136 | ||
137 | if (actual != LM_ST_UNLOCKED && (flags & LM_FLAG_ANY)) | |
138 | return 1; | |
139 | ||
140 | return 0; | |
141 | } | |
142 | ||
143 | /** | |
144 | * gl_hash() - Turn glock number into hash bucket number | |
145 | * @lock: The glock number | |
146 | * | |
147 | * Returns: The number of the corresponding hash bucket | |
148 | */ | |
149 | ||
b8547856 SW |
150 | static unsigned int gl_hash(const struct gfs2_sbd *sdp, |
151 | const struct lm_lockname *name) | |
b3b94faa DT |
152 | { |
153 | unsigned int h; | |
154 | ||
cd915493 | 155 | h = jhash(&name->ln_number, sizeof(u64), 0); |
b3b94faa | 156 | h = jhash(&name->ln_type, sizeof(unsigned int), h); |
b8547856 | 157 | h = jhash(&sdp, sizeof(struct gfs2_sbd *), h); |
b3b94faa DT |
158 | h &= GFS2_GL_HASH_MASK; |
159 | ||
160 | return h; | |
161 | } | |
162 | ||
163 | /** | |
164 | * glock_free() - Perform a few checks and then release struct gfs2_glock | |
165 | * @gl: The glock to release | |
166 | * | |
167 | * Also calls lock module to release its internal structure for this glock. | |
168 | * | |
169 | */ | |
170 | ||
171 | static void glock_free(struct gfs2_glock *gl) | |
172 | { | |
173 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
174 | struct inode *aspace = gl->gl_aspace; | |
175 | ||
176 | gfs2_lm_put_lock(sdp, gl->gl_lock); | |
177 | ||
178 | if (aspace) | |
179 | gfs2_aspace_put(aspace); | |
180 | ||
181 | kmem_cache_free(gfs2_glock_cachep, gl); | |
b3b94faa DT |
182 | } |
183 | ||
184 | /** | |
185 | * gfs2_glock_hold() - increment reference count on glock | |
186 | * @gl: The glock to hold | |
187 | * | |
188 | */ | |
189 | ||
190 | void gfs2_glock_hold(struct gfs2_glock *gl) | |
191 | { | |
16feb9fe | 192 | atomic_inc(&gl->gl_ref); |
b3b94faa DT |
193 | } |
194 | ||
195 | /** | |
196 | * gfs2_glock_put() - Decrement reference count on glock | |
197 | * @gl: The glock to put | |
198 | * | |
199 | */ | |
200 | ||
201 | int gfs2_glock_put(struct gfs2_glock *gl) | |
202 | { | |
b3b94faa | 203 | int rv = 0; |
16feb9fe | 204 | struct gfs2_sbd *sdp = gl->gl_sbd; |
b3b94faa | 205 | |
087efdd3 | 206 | write_lock(gl_lock_addr(gl->gl_hash)); |
16feb9fe | 207 | if (atomic_dec_and_test(&gl->gl_ref)) { |
b6397893 | 208 | hlist_del(&gl->gl_list); |
087efdd3 | 209 | write_unlock(gl_lock_addr(gl->gl_hash)); |
190562bd | 210 | BUG_ON(spin_is_locked(&gl->gl_spin)); |
16feb9fe SW |
211 | gfs2_assert(sdp, gl->gl_state == LM_ST_UNLOCKED); |
212 | gfs2_assert(sdp, list_empty(&gl->gl_reclaim)); | |
213 | gfs2_assert(sdp, list_empty(&gl->gl_holders)); | |
214 | gfs2_assert(sdp, list_empty(&gl->gl_waiters1)); | |
215 | gfs2_assert(sdp, list_empty(&gl->gl_waiters2)); | |
216 | gfs2_assert(sdp, list_empty(&gl->gl_waiters3)); | |
b3b94faa DT |
217 | glock_free(gl); |
218 | rv = 1; | |
219 | goto out; | |
220 | } | |
087efdd3 | 221 | write_unlock(gl_lock_addr(gl->gl_hash)); |
a2242db0 | 222 | out: |
b3b94faa DT |
223 | return rv; |
224 | } | |
225 | ||
b3b94faa DT |
226 | /** |
227 | * search_bucket() - Find struct gfs2_glock by lock number | |
228 | * @bucket: the bucket to search | |
229 | * @name: The lock name | |
230 | * | |
231 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
232 | */ | |
233 | ||
37b2fa6a | 234 | static struct gfs2_glock *search_bucket(unsigned int hash, |
899be4d3 | 235 | const struct gfs2_sbd *sdp, |
d6a53727 | 236 | const struct lm_lockname *name) |
b3b94faa DT |
237 | { |
238 | struct gfs2_glock *gl; | |
b6397893 | 239 | struct hlist_node *h; |
b3b94faa | 240 | |
b6397893 | 241 | hlist_for_each_entry(gl, h, &gl_hash_table[hash].hb_list, gl_list) { |
b3b94faa DT |
242 | if (!lm_name_equal(&gl->gl_name, name)) |
243 | continue; | |
899be4d3 SW |
244 | if (gl->gl_sbd != sdp) |
245 | continue; | |
b3b94faa | 246 | |
16feb9fe | 247 | atomic_inc(&gl->gl_ref); |
b3b94faa DT |
248 | |
249 | return gl; | |
250 | } | |
251 | ||
252 | return NULL; | |
253 | } | |
254 | ||
255 | /** | |
256 | * gfs2_glock_find() - Find glock by lock number | |
257 | * @sdp: The GFS2 superblock | |
258 | * @name: The lock name | |
259 | * | |
260 | * Returns: NULL, or the struct gfs2_glock with the requested number | |
261 | */ | |
262 | ||
85d1da67 | 263 | static struct gfs2_glock *gfs2_glock_find(const struct gfs2_sbd *sdp, |
d6a53727 | 264 | const struct lm_lockname *name) |
b3b94faa | 265 | { |
37b2fa6a | 266 | unsigned int hash = gl_hash(sdp, name); |
b3b94faa DT |
267 | struct gfs2_glock *gl; |
268 | ||
087efdd3 | 269 | read_lock(gl_lock_addr(hash)); |
37b2fa6a | 270 | gl = search_bucket(hash, sdp, name); |
087efdd3 | 271 | read_unlock(gl_lock_addr(hash)); |
b3b94faa DT |
272 | |
273 | return gl; | |
274 | } | |
275 | ||
276 | /** | |
277 | * gfs2_glock_get() - Get a glock, or create one if one doesn't exist | |
278 | * @sdp: The GFS2 superblock | |
279 | * @number: the lock number | |
280 | * @glops: The glock_operations to use | |
281 | * @create: If 0, don't create the glock if it doesn't exist | |
282 | * @glp: the glock is returned here | |
283 | * | |
284 | * This does not lock a glock, just finds/creates structures for one. | |
285 | * | |
286 | * Returns: errno | |
287 | */ | |
288 | ||
cd915493 | 289 | int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 | 290 | const struct gfs2_glock_operations *glops, int create, |
b3b94faa DT |
291 | struct gfs2_glock **glp) |
292 | { | |
37b2fa6a | 293 | struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type }; |
b3b94faa | 294 | struct gfs2_glock *gl, *tmp; |
37b2fa6a | 295 | unsigned int hash = gl_hash(sdp, &name); |
b3b94faa DT |
296 | int error; |
297 | ||
087efdd3 | 298 | read_lock(gl_lock_addr(hash)); |
37b2fa6a | 299 | gl = search_bucket(hash, sdp, &name); |
087efdd3 | 300 | read_unlock(gl_lock_addr(hash)); |
b3b94faa DT |
301 | |
302 | if (gl || !create) { | |
303 | *glp = gl; | |
304 | return 0; | |
305 | } | |
306 | ||
307 | gl = kmem_cache_alloc(gfs2_glock_cachep, GFP_KERNEL); | |
308 | if (!gl) | |
309 | return -ENOMEM; | |
310 | ||
ec45d9f5 | 311 | gl->gl_flags = 0; |
b3b94faa | 312 | gl->gl_name = name; |
16feb9fe | 313 | atomic_set(&gl->gl_ref, 1); |
b3b94faa | 314 | gl->gl_state = LM_ST_UNLOCKED; |
37b2fa6a | 315 | gl->gl_hash = hash; |
320dd101 SW |
316 | gl->gl_owner = NULL; |
317 | gl->gl_ip = 0; | |
b3b94faa | 318 | gl->gl_ops = glops; |
ec45d9f5 SW |
319 | gl->gl_req_gh = NULL; |
320 | gl->gl_req_bh = NULL; | |
321 | gl->gl_vn = 0; | |
322 | gl->gl_stamp = jiffies; | |
323 | gl->gl_object = NULL; | |
b3b94faa | 324 | gl->gl_sbd = sdp; |
ec45d9f5 | 325 | gl->gl_aspace = NULL; |
b3b94faa | 326 | lops_init_le(&gl->gl_le, &gfs2_glock_lops); |
b3b94faa DT |
327 | |
328 | /* If this glock protects actual on-disk data or metadata blocks, | |
329 | create a VFS inode to manage the pages/buffers holding them. */ | |
50299965 | 330 | if (glops == &gfs2_inode_glops || glops == &gfs2_rgrp_glops) { |
b3b94faa DT |
331 | gl->gl_aspace = gfs2_aspace_get(sdp); |
332 | if (!gl->gl_aspace) { | |
333 | error = -ENOMEM; | |
334 | goto fail; | |
335 | } | |
336 | } | |
337 | ||
338 | error = gfs2_lm_get_lock(sdp, &name, &gl->gl_lock); | |
339 | if (error) | |
340 | goto fail_aspace; | |
341 | ||
087efdd3 | 342 | write_lock(gl_lock_addr(hash)); |
37b2fa6a | 343 | tmp = search_bucket(hash, sdp, &name); |
b3b94faa | 344 | if (tmp) { |
087efdd3 | 345 | write_unlock(gl_lock_addr(hash)); |
b3b94faa DT |
346 | glock_free(gl); |
347 | gl = tmp; | |
348 | } else { | |
b6397893 | 349 | hlist_add_head(&gl->gl_list, &gl_hash_table[hash].hb_list); |
087efdd3 | 350 | write_unlock(gl_lock_addr(hash)); |
b3b94faa DT |
351 | } |
352 | ||
353 | *glp = gl; | |
354 | ||
355 | return 0; | |
356 | ||
ec45d9f5 | 357 | fail_aspace: |
b3b94faa DT |
358 | if (gl->gl_aspace) |
359 | gfs2_aspace_put(gl->gl_aspace); | |
ec45d9f5 | 360 | fail: |
907b9bce | 361 | kmem_cache_free(gfs2_glock_cachep, gl); |
b3b94faa DT |
362 | return error; |
363 | } | |
364 | ||
365 | /** | |
366 | * gfs2_holder_init - initialize a struct gfs2_holder in the default way | |
367 | * @gl: the glock | |
368 | * @state: the state we're requesting | |
369 | * @flags: the modifier flags | |
370 | * @gh: the holder structure | |
371 | * | |
372 | */ | |
373 | ||
190562bd | 374 | void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, |
b3b94faa DT |
375 | struct gfs2_holder *gh) |
376 | { | |
377 | INIT_LIST_HEAD(&gh->gh_list); | |
378 | gh->gh_gl = gl; | |
d0dc80db | 379 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
190562bd | 380 | gh->gh_owner = current; |
b3b94faa DT |
381 | gh->gh_state = state; |
382 | gh->gh_flags = flags; | |
383 | gh->gh_error = 0; | |
384 | gh->gh_iflags = 0; | |
b3b94faa DT |
385 | gfs2_glock_hold(gl); |
386 | } | |
387 | ||
388 | /** | |
389 | * gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it | |
390 | * @state: the state we're requesting | |
391 | * @flags: the modifier flags | |
392 | * @gh: the holder structure | |
393 | * | |
394 | * Don't mess with the glock. | |
395 | * | |
396 | */ | |
397 | ||
190562bd | 398 | void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh) |
b3b94faa DT |
399 | { |
400 | gh->gh_state = state; | |
579b78a4 | 401 | gh->gh_flags = flags; |
b3b94faa | 402 | gh->gh_iflags &= 1 << HIF_ALLOCED; |
d0dc80db | 403 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b3b94faa DT |
404 | } |
405 | ||
406 | /** | |
407 | * gfs2_holder_uninit - uninitialize a holder structure (drop glock reference) | |
408 | * @gh: the holder structure | |
409 | * | |
410 | */ | |
411 | ||
412 | void gfs2_holder_uninit(struct gfs2_holder *gh) | |
413 | { | |
414 | gfs2_glock_put(gh->gh_gl); | |
415 | gh->gh_gl = NULL; | |
d0dc80db | 416 | gh->gh_ip = 0; |
b3b94faa DT |
417 | } |
418 | ||
419 | /** | |
420 | * gfs2_holder_get - get a struct gfs2_holder structure | |
421 | * @gl: the glock | |
422 | * @state: the state we're requesting | |
423 | * @flags: the modifier flags | |
af18ddb8 | 424 | * @gfp_flags: |
b3b94faa DT |
425 | * |
426 | * Figure out how big an impact this function has. Either: | |
427 | * 1) Replace it with a cache of structures hanging off the struct gfs2_sbd | |
428 | * 2) Leave it like it is | |
429 | * | |
430 | * Returns: the holder structure, NULL on ENOMEM | |
431 | */ | |
432 | ||
08bc2dbc AB |
433 | static struct gfs2_holder *gfs2_holder_get(struct gfs2_glock *gl, |
434 | unsigned int state, | |
435 | int flags, gfp_t gfp_flags) | |
b3b94faa DT |
436 | { |
437 | struct gfs2_holder *gh; | |
438 | ||
439 | gh = kmalloc(sizeof(struct gfs2_holder), gfp_flags); | |
440 | if (!gh) | |
441 | return NULL; | |
442 | ||
443 | gfs2_holder_init(gl, state, flags, gh); | |
444 | set_bit(HIF_ALLOCED, &gh->gh_iflags); | |
d0dc80db | 445 | gh->gh_ip = (unsigned long)__builtin_return_address(0); |
b3b94faa DT |
446 | return gh; |
447 | } | |
448 | ||
449 | /** | |
450 | * gfs2_holder_put - get rid of a struct gfs2_holder structure | |
451 | * @gh: the holder structure | |
452 | * | |
453 | */ | |
454 | ||
08bc2dbc | 455 | static void gfs2_holder_put(struct gfs2_holder *gh) |
b3b94faa DT |
456 | { |
457 | gfs2_holder_uninit(gh); | |
458 | kfree(gh); | |
459 | } | |
460 | ||
fee852e3 SW |
461 | static void gfs2_holder_dispose_or_wake(struct gfs2_holder *gh) |
462 | { | |
463 | if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) { | |
464 | gfs2_holder_put(gh); | |
465 | return; | |
466 | } | |
467 | clear_bit(HIF_WAIT, &gh->gh_iflags); | |
468 | smp_mb(); | |
469 | wake_up_bit(&gh->gh_iflags, HIF_WAIT); | |
470 | } | |
471 | ||
472 | static int holder_wait(void *word) | |
473 | { | |
474 | schedule(); | |
475 | return 0; | |
476 | } | |
477 | ||
478 | static void wait_on_holder(struct gfs2_holder *gh) | |
479 | { | |
480 | might_sleep(); | |
481 | wait_on_bit(&gh->gh_iflags, HIF_WAIT, holder_wait, TASK_UNINTERRUPTIBLE); | |
482 | } | |
483 | ||
b3b94faa DT |
484 | /** |
485 | * rq_mutex - process a mutex request in the queue | |
486 | * @gh: the glock holder | |
487 | * | |
488 | * Returns: 1 if the queue is blocked | |
489 | */ | |
490 | ||
491 | static int rq_mutex(struct gfs2_holder *gh) | |
492 | { | |
493 | struct gfs2_glock *gl = gh->gh_gl; | |
494 | ||
495 | list_del_init(&gh->gh_list); | |
496 | /* gh->gh_error never examined. */ | |
497 | set_bit(GLF_LOCK, &gl->gl_flags); | |
d043e190 | 498 | clear_bit(HIF_WAIT, &gh->gh_iflags); |
fee852e3 SW |
499 | smp_mb(); |
500 | wake_up_bit(&gh->gh_iflags, HIF_WAIT); | |
b3b94faa DT |
501 | |
502 | return 1; | |
503 | } | |
504 | ||
505 | /** | |
506 | * rq_promote - process a promote request in the queue | |
507 | * @gh: the glock holder | |
508 | * | |
509 | * Acquire a new inter-node lock, or change a lock state to more restrictive. | |
510 | * | |
511 | * Returns: 1 if the queue is blocked | |
512 | */ | |
513 | ||
514 | static int rq_promote(struct gfs2_holder *gh) | |
515 | { | |
516 | struct gfs2_glock *gl = gh->gh_gl; | |
517 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
b3b94faa DT |
518 | |
519 | if (!relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { | |
520 | if (list_empty(&gl->gl_holders)) { | |
521 | gl->gl_req_gh = gh; | |
522 | set_bit(GLF_LOCK, &gl->gl_flags); | |
523 | spin_unlock(&gl->gl_spin); | |
524 | ||
525 | if (atomic_read(&sdp->sd_reclaim_count) > | |
526 | gfs2_tune_get(sdp, gt_reclaim_limit) && | |
527 | !(gh->gh_flags & LM_FLAG_PRIORITY)) { | |
528 | gfs2_reclaim_glock(sdp); | |
529 | gfs2_reclaim_glock(sdp); | |
530 | } | |
531 | ||
b5d32bea | 532 | gfs2_glock_xmote_th(gh); |
b3b94faa DT |
533 | spin_lock(&gl->gl_spin); |
534 | } | |
535 | return 1; | |
536 | } | |
537 | ||
538 | if (list_empty(&gl->gl_holders)) { | |
539 | set_bit(HIF_FIRST, &gh->gh_iflags); | |
540 | set_bit(GLF_LOCK, &gl->gl_flags); | |
b3b94faa DT |
541 | } else { |
542 | struct gfs2_holder *next_gh; | |
1c0f4872 | 543 | if (gh->gh_state == LM_ST_EXCLUSIVE) |
b3b94faa DT |
544 | return 1; |
545 | next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder, | |
546 | gh_list); | |
1c0f4872 | 547 | if (next_gh->gh_state == LM_ST_EXCLUSIVE) |
b3b94faa | 548 | return 1; |
b3b94faa DT |
549 | } |
550 | ||
551 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
552 | gh->gh_error = 0; | |
553 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
554 | ||
fee852e3 | 555 | gfs2_holder_dispose_or_wake(gh); |
b3b94faa DT |
556 | |
557 | return 0; | |
558 | } | |
559 | ||
560 | /** | |
561 | * rq_demote - process a demote request in the queue | |
562 | * @gh: the glock holder | |
563 | * | |
564 | * Returns: 1 if the queue is blocked | |
565 | */ | |
566 | ||
567 | static int rq_demote(struct gfs2_holder *gh) | |
568 | { | |
569 | struct gfs2_glock *gl = gh->gh_gl; | |
b3b94faa DT |
570 | |
571 | if (!list_empty(&gl->gl_holders)) | |
572 | return 1; | |
573 | ||
574 | if (gl->gl_state == gh->gh_state || gl->gl_state == LM_ST_UNLOCKED) { | |
575 | list_del_init(&gh->gh_list); | |
576 | gh->gh_error = 0; | |
577 | spin_unlock(&gl->gl_spin); | |
fee852e3 | 578 | gfs2_holder_dispose_or_wake(gh); |
b3b94faa DT |
579 | spin_lock(&gl->gl_spin); |
580 | } else { | |
581 | gl->gl_req_gh = gh; | |
582 | set_bit(GLF_LOCK, &gl->gl_flags); | |
583 | spin_unlock(&gl->gl_spin); | |
584 | ||
585 | if (gh->gh_state == LM_ST_UNLOCKED || | |
586 | gl->gl_state != LM_ST_EXCLUSIVE) | |
b5d32bea | 587 | gfs2_glock_drop_th(gl); |
b3b94faa | 588 | else |
b5d32bea | 589 | gfs2_glock_xmote_th(gh); |
b3b94faa DT |
590 | |
591 | spin_lock(&gl->gl_spin); | |
592 | } | |
593 | ||
594 | return 0; | |
595 | } | |
596 | ||
b3b94faa DT |
597 | /** |
598 | * run_queue - process holder structures on a glock | |
599 | * @gl: the glock | |
600 | * | |
601 | */ | |
b3b94faa DT |
602 | static void run_queue(struct gfs2_glock *gl) |
603 | { | |
604 | struct gfs2_holder *gh; | |
605 | int blocked = 1; | |
606 | ||
607 | for (;;) { | |
608 | if (test_bit(GLF_LOCK, &gl->gl_flags)) | |
609 | break; | |
610 | ||
611 | if (!list_empty(&gl->gl_waiters1)) { | |
612 | gh = list_entry(gl->gl_waiters1.next, | |
613 | struct gfs2_holder, gh_list); | |
614 | ||
615 | if (test_bit(HIF_MUTEX, &gh->gh_iflags)) | |
616 | blocked = rq_mutex(gh); | |
617 | else | |
618 | gfs2_assert_warn(gl->gl_sbd, 0); | |
619 | ||
620 | } else if (!list_empty(&gl->gl_waiters2) && | |
621 | !test_bit(GLF_SKIP_WAITERS2, &gl->gl_flags)) { | |
622 | gh = list_entry(gl->gl_waiters2.next, | |
623 | struct gfs2_holder, gh_list); | |
624 | ||
625 | if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) | |
626 | blocked = rq_demote(gh); | |
b3b94faa DT |
627 | else |
628 | gfs2_assert_warn(gl->gl_sbd, 0); | |
629 | ||
630 | } else if (!list_empty(&gl->gl_waiters3)) { | |
631 | gh = list_entry(gl->gl_waiters3.next, | |
632 | struct gfs2_holder, gh_list); | |
633 | ||
634 | if (test_bit(HIF_PROMOTE, &gh->gh_iflags)) | |
635 | blocked = rq_promote(gh); | |
636 | else | |
637 | gfs2_assert_warn(gl->gl_sbd, 0); | |
638 | ||
639 | } else | |
640 | break; | |
641 | ||
642 | if (blocked) | |
643 | break; | |
644 | } | |
645 | } | |
646 | ||
647 | /** | |
648 | * gfs2_glmutex_lock - acquire a local lock on a glock | |
649 | * @gl: the glock | |
650 | * | |
651 | * Gives caller exclusive access to manipulate a glock structure. | |
652 | */ | |
653 | ||
feaa7bba | 654 | static void gfs2_glmutex_lock(struct gfs2_glock *gl) |
b3b94faa DT |
655 | { |
656 | struct gfs2_holder gh; | |
657 | ||
658 | gfs2_holder_init(gl, 0, 0, &gh); | |
659 | set_bit(HIF_MUTEX, &gh.gh_iflags); | |
fee852e3 SW |
660 | if (test_and_set_bit(HIF_WAIT, &gh.gh_iflags)) |
661 | BUG(); | |
b3b94faa DT |
662 | |
663 | spin_lock(&gl->gl_spin); | |
85d1da67 | 664 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { |
b3b94faa | 665 | list_add_tail(&gh.gh_list, &gl->gl_waiters1); |
85d1da67 | 666 | } else { |
320dd101 SW |
667 | gl->gl_owner = current; |
668 | gl->gl_ip = (unsigned long)__builtin_return_address(0); | |
fee852e3 SW |
669 | clear_bit(HIF_WAIT, &gh.gh_iflags); |
670 | smp_mb(); | |
671 | wake_up_bit(&gh.gh_iflags, HIF_WAIT); | |
320dd101 | 672 | } |
b3b94faa DT |
673 | spin_unlock(&gl->gl_spin); |
674 | ||
fee852e3 | 675 | wait_on_holder(&gh); |
b3b94faa DT |
676 | gfs2_holder_uninit(&gh); |
677 | } | |
678 | ||
679 | /** | |
680 | * gfs2_glmutex_trylock - try to acquire a local lock on a glock | |
681 | * @gl: the glock | |
682 | * | |
683 | * Returns: 1 if the glock is acquired | |
684 | */ | |
685 | ||
08bc2dbc | 686 | static int gfs2_glmutex_trylock(struct gfs2_glock *gl) |
b3b94faa DT |
687 | { |
688 | int acquired = 1; | |
689 | ||
690 | spin_lock(&gl->gl_spin); | |
85d1da67 | 691 | if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) { |
b3b94faa | 692 | acquired = 0; |
85d1da67 | 693 | } else { |
320dd101 SW |
694 | gl->gl_owner = current; |
695 | gl->gl_ip = (unsigned long)__builtin_return_address(0); | |
696 | } | |
b3b94faa DT |
697 | spin_unlock(&gl->gl_spin); |
698 | ||
699 | return acquired; | |
700 | } | |
701 | ||
702 | /** | |
703 | * gfs2_glmutex_unlock - release a local lock on a glock | |
704 | * @gl: the glock | |
705 | * | |
706 | */ | |
707 | ||
feaa7bba | 708 | static void gfs2_glmutex_unlock(struct gfs2_glock *gl) |
b3b94faa DT |
709 | { |
710 | spin_lock(&gl->gl_spin); | |
711 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
320dd101 SW |
712 | gl->gl_owner = NULL; |
713 | gl->gl_ip = 0; | |
b3b94faa | 714 | run_queue(gl); |
190562bd | 715 | BUG_ON(!spin_is_locked(&gl->gl_spin)); |
b3b94faa DT |
716 | spin_unlock(&gl->gl_spin); |
717 | } | |
718 | ||
719 | /** | |
720 | * handle_callback - add a demote request to a lock's queue | |
721 | * @gl: the glock | |
722 | * @state: the state the caller wants us to change to | |
723 | * | |
af18ddb8 | 724 | * Note: This may fail sliently if we are out of memory. |
b3b94faa DT |
725 | */ |
726 | ||
727 | static void handle_callback(struct gfs2_glock *gl, unsigned int state) | |
728 | { | |
729 | struct gfs2_holder *gh, *new_gh = NULL; | |
730 | ||
feaa7bba | 731 | restart: |
b3b94faa DT |
732 | spin_lock(&gl->gl_spin); |
733 | ||
734 | list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { | |
735 | if (test_bit(HIF_DEMOTE, &gh->gh_iflags) && | |
736 | gl->gl_req_gh != gh) { | |
737 | if (gh->gh_state != state) | |
738 | gh->gh_state = LM_ST_UNLOCKED; | |
739 | goto out; | |
740 | } | |
741 | } | |
742 | ||
743 | if (new_gh) { | |
744 | list_add_tail(&new_gh->gh_list, &gl->gl_waiters2); | |
745 | new_gh = NULL; | |
746 | } else { | |
747 | spin_unlock(&gl->gl_spin); | |
748 | ||
ab923031 | 749 | new_gh = gfs2_holder_get(gl, state, LM_FLAG_TRY, GFP_NOFS); |
af18ddb8 SW |
750 | if (!new_gh) |
751 | return; | |
b3b94faa DT |
752 | set_bit(HIF_DEMOTE, &new_gh->gh_iflags); |
753 | set_bit(HIF_DEALLOC, &new_gh->gh_iflags); | |
fee852e3 | 754 | set_bit(HIF_WAIT, &new_gh->gh_iflags); |
b3b94faa DT |
755 | |
756 | goto restart; | |
757 | } | |
758 | ||
feaa7bba | 759 | out: |
b3b94faa DT |
760 | spin_unlock(&gl->gl_spin); |
761 | ||
762 | if (new_gh) | |
763 | gfs2_holder_put(new_gh); | |
764 | } | |
765 | ||
766 | /** | |
767 | * state_change - record that the glock is now in a different state | |
768 | * @gl: the glock | |
769 | * @new_state the new state | |
770 | * | |
771 | */ | |
772 | ||
773 | static void state_change(struct gfs2_glock *gl, unsigned int new_state) | |
774 | { | |
b3b94faa DT |
775 | int held1, held2; |
776 | ||
777 | held1 = (gl->gl_state != LM_ST_UNLOCKED); | |
778 | held2 = (new_state != LM_ST_UNLOCKED); | |
779 | ||
780 | if (held1 != held2) { | |
6a6b3d01 | 781 | if (held2) |
b3b94faa | 782 | gfs2_glock_hold(gl); |
6a6b3d01 | 783 | else |
b3b94faa | 784 | gfs2_glock_put(gl); |
b3b94faa DT |
785 | } |
786 | ||
787 | gl->gl_state = new_state; | |
788 | } | |
789 | ||
790 | /** | |
791 | * xmote_bh - Called after the lock module is done acquiring a lock | |
792 | * @gl: The glock in question | |
793 | * @ret: the int returned from the lock module | |
794 | * | |
795 | */ | |
796 | ||
797 | static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) | |
798 | { | |
799 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 800 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
801 | struct gfs2_holder *gh = gl->gl_req_gh; |
802 | int prev_state = gl->gl_state; | |
803 | int op_done = 1; | |
804 | ||
805 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
12132933 | 806 | gfs2_assert_warn(sdp, list_empty(&gl->gl_holders)); |
b3b94faa DT |
807 | gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC)); |
808 | ||
809 | state_change(gl, ret & LM_OUT_ST_MASK); | |
810 | ||
811 | if (prev_state != LM_ST_UNLOCKED && !(ret & LM_OUT_CACHEABLE)) { | |
812 | if (glops->go_inval) | |
1a14d3a6 | 813 | glops->go_inval(gl, DIO_METADATA); |
b3b94faa DT |
814 | } else if (gl->gl_state == LM_ST_DEFERRED) { |
815 | /* We might not want to do this here. | |
816 | Look at moving to the inode glops. */ | |
817 | if (glops->go_inval) | |
1a14d3a6 | 818 | glops->go_inval(gl, 0); |
b3b94faa DT |
819 | } |
820 | ||
821 | /* Deal with each possible exit condition */ | |
822 | ||
823 | if (!gh) | |
824 | gl->gl_stamp = jiffies; | |
b3b94faa DT |
825 | else if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { |
826 | spin_lock(&gl->gl_spin); | |
827 | list_del_init(&gh->gh_list); | |
828 | gh->gh_error = -EIO; | |
b3b94faa | 829 | spin_unlock(&gl->gl_spin); |
b3b94faa DT |
830 | } else if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) { |
831 | spin_lock(&gl->gl_spin); | |
832 | list_del_init(&gh->gh_list); | |
833 | if (gl->gl_state == gh->gh_state || | |
85d1da67 | 834 | gl->gl_state == LM_ST_UNLOCKED) { |
b3b94faa | 835 | gh->gh_error = 0; |
85d1da67 | 836 | } else { |
b3b94faa DT |
837 | if (gfs2_assert_warn(sdp, gh->gh_flags & |
838 | (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) == -1) | |
839 | fs_warn(sdp, "ret = 0x%.8X\n", ret); | |
840 | gh->gh_error = GLR_TRYFAILED; | |
841 | } | |
842 | spin_unlock(&gl->gl_spin); | |
843 | ||
844 | if (ret & LM_OUT_CANCELED) | |
50299965 | 845 | handle_callback(gl, LM_ST_UNLOCKED); |
b3b94faa DT |
846 | |
847 | } else if (ret & LM_OUT_CANCELED) { | |
848 | spin_lock(&gl->gl_spin); | |
849 | list_del_init(&gh->gh_list); | |
850 | gh->gh_error = GLR_CANCELED; | |
b3b94faa DT |
851 | spin_unlock(&gl->gl_spin); |
852 | ||
853 | } else if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { | |
854 | spin_lock(&gl->gl_spin); | |
855 | list_move_tail(&gh->gh_list, &gl->gl_holders); | |
856 | gh->gh_error = 0; | |
857 | set_bit(HIF_HOLDER, &gh->gh_iflags); | |
858 | spin_unlock(&gl->gl_spin); | |
859 | ||
860 | set_bit(HIF_FIRST, &gh->gh_iflags); | |
861 | ||
862 | op_done = 0; | |
863 | ||
864 | } else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { | |
865 | spin_lock(&gl->gl_spin); | |
866 | list_del_init(&gh->gh_list); | |
867 | gh->gh_error = GLR_TRYFAILED; | |
b3b94faa DT |
868 | spin_unlock(&gl->gl_spin); |
869 | ||
870 | } else { | |
871 | if (gfs2_assert_withdraw(sdp, 0) == -1) | |
872 | fs_err(sdp, "ret = 0x%.8X\n", ret); | |
873 | } | |
874 | ||
875 | if (glops->go_xmote_bh) | |
876 | glops->go_xmote_bh(gl); | |
877 | ||
878 | if (op_done) { | |
879 | spin_lock(&gl->gl_spin); | |
880 | gl->gl_req_gh = NULL; | |
881 | gl->gl_req_bh = NULL; | |
882 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
883 | run_queue(gl); | |
884 | spin_unlock(&gl->gl_spin); | |
885 | } | |
886 | ||
887 | gfs2_glock_put(gl); | |
888 | ||
fee852e3 SW |
889 | if (gh) |
890 | gfs2_holder_dispose_or_wake(gh); | |
b3b94faa DT |
891 | } |
892 | ||
893 | /** | |
894 | * gfs2_glock_xmote_th - Call into the lock module to acquire or change a glock | |
895 | * @gl: The glock in question | |
896 | * @state: the requested state | |
897 | * @flags: modifier flags to the lock call | |
898 | * | |
899 | */ | |
900 | ||
b5d32bea | 901 | void gfs2_glock_xmote_th(struct gfs2_holder *gh) |
b3b94faa | 902 | { |
b5d32bea | 903 | struct gfs2_glock *gl = gh->gh_gl; |
b3b94faa | 904 | struct gfs2_sbd *sdp = gl->gl_sbd; |
b5d32bea SW |
905 | int flags = gh->gh_flags; |
906 | unsigned state = gh->gh_state; | |
8fb4b536 | 907 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
908 | int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB | |
909 | LM_FLAG_NOEXP | LM_FLAG_ANY | | |
910 | LM_FLAG_PRIORITY); | |
911 | unsigned int lck_ret; | |
912 | ||
b5d32bea SW |
913 | if (glops->go_xmote_th) |
914 | glops->go_xmote_th(gl); | |
915 | ||
b3b94faa | 916 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); |
12132933 | 917 | gfs2_assert_warn(sdp, list_empty(&gl->gl_holders)); |
b3b94faa DT |
918 | gfs2_assert_warn(sdp, state != LM_ST_UNLOCKED); |
919 | gfs2_assert_warn(sdp, state != gl->gl_state); | |
920 | ||
b3b94faa DT |
921 | gfs2_glock_hold(gl); |
922 | gl->gl_req_bh = xmote_bh; | |
923 | ||
ec45d9f5 | 924 | lck_ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, state, lck_flags); |
b3b94faa DT |
925 | |
926 | if (gfs2_assert_withdraw(sdp, !(lck_ret & LM_OUT_ERROR))) | |
927 | return; | |
928 | ||
929 | if (lck_ret & LM_OUT_ASYNC) | |
930 | gfs2_assert_warn(sdp, lck_ret == LM_OUT_ASYNC); | |
931 | else | |
932 | xmote_bh(gl, lck_ret); | |
933 | } | |
934 | ||
935 | /** | |
936 | * drop_bh - Called after a lock module unlock completes | |
937 | * @gl: the glock | |
938 | * @ret: the return status | |
939 | * | |
940 | * Doesn't wake up the process waiting on the struct gfs2_holder (if any) | |
941 | * Doesn't drop the reference on the glock the top half took out | |
942 | * | |
943 | */ | |
944 | ||
945 | static void drop_bh(struct gfs2_glock *gl, unsigned int ret) | |
946 | { | |
947 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 948 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
949 | struct gfs2_holder *gh = gl->gl_req_gh; |
950 | ||
b3b94faa | 951 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); |
12132933 | 952 | gfs2_assert_warn(sdp, list_empty(&gl->gl_holders)); |
b3b94faa DT |
953 | gfs2_assert_warn(sdp, !ret); |
954 | ||
955 | state_change(gl, LM_ST_UNLOCKED); | |
956 | ||
957 | if (glops->go_inval) | |
1a14d3a6 | 958 | glops->go_inval(gl, DIO_METADATA); |
b3b94faa DT |
959 | |
960 | if (gh) { | |
961 | spin_lock(&gl->gl_spin); | |
962 | list_del_init(&gh->gh_list); | |
963 | gh->gh_error = 0; | |
964 | spin_unlock(&gl->gl_spin); | |
965 | } | |
966 | ||
b3b94faa DT |
967 | spin_lock(&gl->gl_spin); |
968 | gl->gl_req_gh = NULL; | |
969 | gl->gl_req_bh = NULL; | |
970 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
971 | run_queue(gl); | |
972 | spin_unlock(&gl->gl_spin); | |
973 | ||
974 | gfs2_glock_put(gl); | |
975 | ||
fee852e3 SW |
976 | if (gh) |
977 | gfs2_holder_dispose_or_wake(gh); | |
b3b94faa DT |
978 | } |
979 | ||
980 | /** | |
981 | * gfs2_glock_drop_th - call into the lock module to unlock a lock | |
982 | * @gl: the glock | |
983 | * | |
984 | */ | |
985 | ||
b5d32bea | 986 | static void gfs2_glock_drop_th(struct gfs2_glock *gl) |
b3b94faa DT |
987 | { |
988 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 989 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
990 | unsigned int ret; |
991 | ||
b5d32bea SW |
992 | if (glops->go_drop_th) |
993 | glops->go_drop_th(gl); | |
994 | ||
b3b94faa | 995 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); |
12132933 | 996 | gfs2_assert_warn(sdp, list_empty(&gl->gl_holders)); |
b3b94faa DT |
997 | gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED); |
998 | ||
b3b94faa DT |
999 | gfs2_glock_hold(gl); |
1000 | gl->gl_req_bh = drop_bh; | |
1001 | ||
b3b94faa DT |
1002 | ret = gfs2_lm_unlock(sdp, gl->gl_lock, gl->gl_state); |
1003 | ||
1004 | if (gfs2_assert_withdraw(sdp, !(ret & LM_OUT_ERROR))) | |
1005 | return; | |
1006 | ||
1007 | if (!ret) | |
1008 | drop_bh(gl, ret); | |
1009 | else | |
1010 | gfs2_assert_warn(sdp, ret == LM_OUT_ASYNC); | |
1011 | } | |
1012 | ||
1013 | /** | |
1014 | * do_cancels - cancel requests for locks stuck waiting on an expire flag | |
1015 | * @gh: the LM_FLAG_PRIORITY holder waiting to acquire the lock | |
1016 | * | |
1017 | * Don't cancel GL_NOCANCEL requests. | |
1018 | */ | |
1019 | ||
1020 | static void do_cancels(struct gfs2_holder *gh) | |
1021 | { | |
1022 | struct gfs2_glock *gl = gh->gh_gl; | |
1023 | ||
1024 | spin_lock(&gl->gl_spin); | |
1025 | ||
1026 | while (gl->gl_req_gh != gh && | |
1027 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && | |
1028 | !list_empty(&gh->gh_list)) { | |
50299965 SW |
1029 | if (gl->gl_req_bh && !(gl->gl_req_gh && |
1030 | (gl->gl_req_gh->gh_flags & GL_NOCANCEL))) { | |
b3b94faa DT |
1031 | spin_unlock(&gl->gl_spin); |
1032 | gfs2_lm_cancel(gl->gl_sbd, gl->gl_lock); | |
1033 | msleep(100); | |
1034 | spin_lock(&gl->gl_spin); | |
1035 | } else { | |
1036 | spin_unlock(&gl->gl_spin); | |
1037 | msleep(100); | |
1038 | spin_lock(&gl->gl_spin); | |
1039 | } | |
1040 | } | |
1041 | ||
1042 | spin_unlock(&gl->gl_spin); | |
1043 | } | |
1044 | ||
1045 | /** | |
1046 | * glock_wait_internal - wait on a glock acquisition | |
1047 | * @gh: the glock holder | |
1048 | * | |
1049 | * Returns: 0 on success | |
1050 | */ | |
1051 | ||
1052 | static int glock_wait_internal(struct gfs2_holder *gh) | |
1053 | { | |
1054 | struct gfs2_glock *gl = gh->gh_gl; | |
1055 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
8fb4b536 | 1056 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1057 | |
1058 | if (test_bit(HIF_ABORTED, &gh->gh_iflags)) | |
1059 | return -EIO; | |
1060 | ||
1061 | if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { | |
1062 | spin_lock(&gl->gl_spin); | |
1063 | if (gl->gl_req_gh != gh && | |
1064 | !test_bit(HIF_HOLDER, &gh->gh_iflags) && | |
1065 | !list_empty(&gh->gh_list)) { | |
1066 | list_del_init(&gh->gh_list); | |
1067 | gh->gh_error = GLR_TRYFAILED; | |
b3b94faa DT |
1068 | run_queue(gl); |
1069 | spin_unlock(&gl->gl_spin); | |
1070 | return gh->gh_error; | |
1071 | } | |
1072 | spin_unlock(&gl->gl_spin); | |
1073 | } | |
1074 | ||
1075 | if (gh->gh_flags & LM_FLAG_PRIORITY) | |
1076 | do_cancels(gh); | |
1077 | ||
fee852e3 | 1078 | wait_on_holder(gh); |
b3b94faa DT |
1079 | if (gh->gh_error) |
1080 | return gh->gh_error; | |
1081 | ||
1082 | gfs2_assert_withdraw(sdp, test_bit(HIF_HOLDER, &gh->gh_iflags)); | |
85d1da67 | 1083 | gfs2_assert_withdraw(sdp, relaxed_state_ok(gl->gl_state, gh->gh_state, |
b3b94faa DT |
1084 | gh->gh_flags)); |
1085 | ||
1086 | if (test_bit(HIF_FIRST, &gh->gh_iflags)) { | |
1087 | gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags)); | |
1088 | ||
1089 | if (glops->go_lock) { | |
1090 | gh->gh_error = glops->go_lock(gh); | |
1091 | if (gh->gh_error) { | |
1092 | spin_lock(&gl->gl_spin); | |
1093 | list_del_init(&gh->gh_list); | |
b3b94faa DT |
1094 | spin_unlock(&gl->gl_spin); |
1095 | } | |
1096 | } | |
1097 | ||
1098 | spin_lock(&gl->gl_spin); | |
1099 | gl->gl_req_gh = NULL; | |
1100 | gl->gl_req_bh = NULL; | |
1101 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
b3b94faa DT |
1102 | run_queue(gl); |
1103 | spin_unlock(&gl->gl_spin); | |
1104 | } | |
1105 | ||
1106 | return gh->gh_error; | |
1107 | } | |
1108 | ||
1109 | static inline struct gfs2_holder * | |
1110 | find_holder_by_owner(struct list_head *head, struct task_struct *owner) | |
1111 | { | |
1112 | struct gfs2_holder *gh; | |
1113 | ||
1114 | list_for_each_entry(gh, head, gh_list) { | |
1115 | if (gh->gh_owner == owner) | |
1116 | return gh; | |
1117 | } | |
1118 | ||
1119 | return NULL; | |
1120 | } | |
1121 | ||
7c52b166 RP |
1122 | static void print_dbg(struct glock_iter *gi, const char *fmt, ...) |
1123 | { | |
1124 | va_list args; | |
1125 | ||
1126 | va_start(args, fmt); | |
1127 | if (gi) { | |
1128 | vsprintf(gi->string, fmt, args); | |
1129 | seq_printf(gi->seq, gi->string); | |
1130 | } | |
1131 | else | |
1132 | vprintk(fmt, args); | |
1133 | va_end(args); | |
1134 | } | |
1135 | ||
b3b94faa DT |
1136 | /** |
1137 | * add_to_queue - Add a holder to the wait queue (but look for recursion) | |
1138 | * @gh: the holder structure to add | |
1139 | * | |
1140 | */ | |
1141 | ||
1142 | static void add_to_queue(struct gfs2_holder *gh) | |
1143 | { | |
1144 | struct gfs2_glock *gl = gh->gh_gl; | |
1145 | struct gfs2_holder *existing; | |
1146 | ||
190562bd | 1147 | BUG_ON(!gh->gh_owner); |
fee852e3 SW |
1148 | if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags)) |
1149 | BUG(); | |
190562bd | 1150 | |
b3b94faa DT |
1151 | existing = find_holder_by_owner(&gl->gl_holders, gh->gh_owner); |
1152 | if (existing) { | |
5965b1f4 | 1153 | print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip); |
86384605 | 1154 | printk(KERN_INFO "pid : %d\n", existing->gh_owner->pid); |
907b9bce | 1155 | printk(KERN_INFO "lock type : %d lock state : %d\n", |
86384605 | 1156 | existing->gh_gl->gl_name.ln_type, existing->gh_gl->gl_state); |
5965b1f4 | 1157 | print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip); |
86384605 | 1158 | printk(KERN_INFO "pid : %d\n", gh->gh_owner->pid); |
907b9bce | 1159 | printk(KERN_INFO "lock type : %d lock state : %d\n", |
86384605 | 1160 | gl->gl_name.ln_type, gl->gl_state); |
5965b1f4 | 1161 | BUG(); |
b3b94faa DT |
1162 | } |
1163 | ||
1164 | existing = find_holder_by_owner(&gl->gl_waiters3, gh->gh_owner); | |
1165 | if (existing) { | |
5965b1f4 SW |
1166 | print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip); |
1167 | print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip); | |
1168 | BUG(); | |
b3b94faa DT |
1169 | } |
1170 | ||
b3b94faa DT |
1171 | if (gh->gh_flags & LM_FLAG_PRIORITY) |
1172 | list_add(&gh->gh_list, &gl->gl_waiters3); | |
1173 | else | |
907b9bce | 1174 | list_add_tail(&gh->gh_list, &gl->gl_waiters3); |
b3b94faa DT |
1175 | } |
1176 | ||
1177 | /** | |
1178 | * gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock) | |
1179 | * @gh: the holder structure | |
1180 | * | |
1181 | * if (gh->gh_flags & GL_ASYNC), this never returns an error | |
1182 | * | |
1183 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1184 | */ | |
1185 | ||
1186 | int gfs2_glock_nq(struct gfs2_holder *gh) | |
1187 | { | |
1188 | struct gfs2_glock *gl = gh->gh_gl; | |
1189 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1190 | int error = 0; | |
1191 | ||
320dd101 | 1192 | restart: |
b3b94faa DT |
1193 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { |
1194 | set_bit(HIF_ABORTED, &gh->gh_iflags); | |
1195 | return -EIO; | |
1196 | } | |
1197 | ||
1198 | set_bit(HIF_PROMOTE, &gh->gh_iflags); | |
1199 | ||
1200 | spin_lock(&gl->gl_spin); | |
1201 | add_to_queue(gh); | |
1202 | run_queue(gl); | |
1203 | spin_unlock(&gl->gl_spin); | |
1204 | ||
1205 | if (!(gh->gh_flags & GL_ASYNC)) { | |
1206 | error = glock_wait_internal(gh); | |
1207 | if (error == GLR_CANCELED) { | |
190562bd | 1208 | msleep(100); |
b3b94faa DT |
1209 | goto restart; |
1210 | } | |
1211 | } | |
1212 | ||
b3b94faa DT |
1213 | return error; |
1214 | } | |
1215 | ||
1216 | /** | |
1217 | * gfs2_glock_poll - poll to see if an async request has been completed | |
1218 | * @gh: the holder | |
1219 | * | |
1220 | * Returns: 1 if the request is ready to be gfs2_glock_wait()ed on | |
1221 | */ | |
1222 | ||
1223 | int gfs2_glock_poll(struct gfs2_holder *gh) | |
1224 | { | |
1225 | struct gfs2_glock *gl = gh->gh_gl; | |
1226 | int ready = 0; | |
1227 | ||
1228 | spin_lock(&gl->gl_spin); | |
1229 | ||
1230 | if (test_bit(HIF_HOLDER, &gh->gh_iflags)) | |
1231 | ready = 1; | |
1232 | else if (list_empty(&gh->gh_list)) { | |
1233 | if (gh->gh_error == GLR_CANCELED) { | |
1234 | spin_unlock(&gl->gl_spin); | |
190562bd | 1235 | msleep(100); |
b3b94faa DT |
1236 | if (gfs2_glock_nq(gh)) |
1237 | return 1; | |
1238 | return 0; | |
1239 | } else | |
1240 | ready = 1; | |
1241 | } | |
1242 | ||
1243 | spin_unlock(&gl->gl_spin); | |
1244 | ||
1245 | return ready; | |
1246 | } | |
1247 | ||
1248 | /** | |
1249 | * gfs2_glock_wait - wait for a lock acquisition that ended in a GLR_ASYNC | |
1250 | * @gh: the holder structure | |
1251 | * | |
1252 | * Returns: 0, GLR_TRYFAILED, or errno on failure | |
1253 | */ | |
1254 | ||
1255 | int gfs2_glock_wait(struct gfs2_holder *gh) | |
1256 | { | |
1257 | int error; | |
1258 | ||
1259 | error = glock_wait_internal(gh); | |
1260 | if (error == GLR_CANCELED) { | |
190562bd | 1261 | msleep(100); |
b3b94faa DT |
1262 | gh->gh_flags &= ~GL_ASYNC; |
1263 | error = gfs2_glock_nq(gh); | |
1264 | } | |
1265 | ||
1266 | return error; | |
1267 | } | |
1268 | ||
1269 | /** | |
1270 | * gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock) | |
1271 | * @gh: the glock holder | |
1272 | * | |
1273 | */ | |
1274 | ||
1275 | void gfs2_glock_dq(struct gfs2_holder *gh) | |
1276 | { | |
1277 | struct gfs2_glock *gl = gh->gh_gl; | |
8fb4b536 | 1278 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa | 1279 | |
b3b94faa DT |
1280 | if (gh->gh_flags & GL_NOCACHE) |
1281 | handle_callback(gl, LM_ST_UNLOCKED); | |
1282 | ||
1283 | gfs2_glmutex_lock(gl); | |
1284 | ||
1285 | spin_lock(&gl->gl_spin); | |
1286 | list_del_init(&gh->gh_list); | |
1287 | ||
1288 | if (list_empty(&gl->gl_holders)) { | |
1289 | spin_unlock(&gl->gl_spin); | |
1290 | ||
1291 | if (glops->go_unlock) | |
1292 | glops->go_unlock(gh); | |
1293 | ||
b3b94faa DT |
1294 | gl->gl_stamp = jiffies; |
1295 | ||
1296 | spin_lock(&gl->gl_spin); | |
1297 | } | |
1298 | ||
1299 | clear_bit(GLF_LOCK, &gl->gl_flags); | |
1300 | run_queue(gl); | |
1301 | spin_unlock(&gl->gl_spin); | |
1302 | } | |
1303 | ||
b3b94faa DT |
1304 | /** |
1305 | * gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it | |
1306 | * @gh: the holder structure | |
1307 | * | |
1308 | */ | |
1309 | ||
1310 | void gfs2_glock_dq_uninit(struct gfs2_holder *gh) | |
1311 | { | |
1312 | gfs2_glock_dq(gh); | |
1313 | gfs2_holder_uninit(gh); | |
1314 | } | |
1315 | ||
1316 | /** | |
1317 | * gfs2_glock_nq_num - acquire a glock based on lock number | |
1318 | * @sdp: the filesystem | |
1319 | * @number: the lock number | |
1320 | * @glops: the glock operations for the type of glock | |
1321 | * @state: the state to acquire the glock in | |
1322 | * @flags: modifier flags for the aquisition | |
1323 | * @gh: the struct gfs2_holder | |
1324 | * | |
1325 | * Returns: errno | |
1326 | */ | |
1327 | ||
cd915493 | 1328 | int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number, |
8fb4b536 SW |
1329 | const struct gfs2_glock_operations *glops, |
1330 | unsigned int state, int flags, struct gfs2_holder *gh) | |
b3b94faa DT |
1331 | { |
1332 | struct gfs2_glock *gl; | |
1333 | int error; | |
1334 | ||
1335 | error = gfs2_glock_get(sdp, number, glops, CREATE, &gl); | |
1336 | if (!error) { | |
1337 | error = gfs2_glock_nq_init(gl, state, flags, gh); | |
1338 | gfs2_glock_put(gl); | |
1339 | } | |
1340 | ||
1341 | return error; | |
1342 | } | |
1343 | ||
1344 | /** | |
1345 | * glock_compare - Compare two struct gfs2_glock structures for sorting | |
1346 | * @arg_a: the first structure | |
1347 | * @arg_b: the second structure | |
1348 | * | |
1349 | */ | |
1350 | ||
1351 | static int glock_compare(const void *arg_a, const void *arg_b) | |
1352 | { | |
a5e08a9e SW |
1353 | const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a; |
1354 | const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b; | |
1355 | const struct lm_lockname *a = &gh_a->gh_gl->gl_name; | |
1356 | const struct lm_lockname *b = &gh_b->gh_gl->gl_name; | |
b3b94faa DT |
1357 | |
1358 | if (a->ln_number > b->ln_number) | |
a5e08a9e SW |
1359 | return 1; |
1360 | if (a->ln_number < b->ln_number) | |
1361 | return -1; | |
1c0f4872 | 1362 | BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type); |
a5e08a9e | 1363 | return 0; |
b3b94faa DT |
1364 | } |
1365 | ||
1366 | /** | |
1367 | * nq_m_sync - synchonously acquire more than one glock in deadlock free order | |
1368 | * @num_gh: the number of structures | |
1369 | * @ghs: an array of struct gfs2_holder structures | |
1370 | * | |
1371 | * Returns: 0 on success (all glocks acquired), | |
1372 | * errno on failure (no glocks acquired) | |
1373 | */ | |
1374 | ||
1375 | static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs, | |
1376 | struct gfs2_holder **p) | |
1377 | { | |
1378 | unsigned int x; | |
1379 | int error = 0; | |
1380 | ||
1381 | for (x = 0; x < num_gh; x++) | |
1382 | p[x] = &ghs[x]; | |
1383 | ||
1384 | sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL); | |
1385 | ||
1386 | for (x = 0; x < num_gh; x++) { | |
1387 | p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1388 | ||
1389 | error = gfs2_glock_nq(p[x]); | |
1390 | if (error) { | |
1391 | while (x--) | |
1392 | gfs2_glock_dq(p[x]); | |
1393 | break; | |
1394 | } | |
1395 | } | |
1396 | ||
1397 | return error; | |
1398 | } | |
1399 | ||
1400 | /** | |
1401 | * gfs2_glock_nq_m - acquire multiple glocks | |
1402 | * @num_gh: the number of structures | |
1403 | * @ghs: an array of struct gfs2_holder structures | |
1404 | * | |
1405 | * Figure out how big an impact this function has. Either: | |
1406 | * 1) Replace this code with code that calls gfs2_glock_prefetch() | |
1407 | * 2) Forget async stuff and just call nq_m_sync() | |
1408 | * 3) Leave it like it is | |
1409 | * | |
1410 | * Returns: 0 on success (all glocks acquired), | |
1411 | * errno on failure (no glocks acquired) | |
1412 | */ | |
1413 | ||
1414 | int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1415 | { | |
1416 | int *e; | |
1417 | unsigned int x; | |
1418 | int borked = 0, serious = 0; | |
1419 | int error = 0; | |
1420 | ||
1421 | if (!num_gh) | |
1422 | return 0; | |
1423 | ||
1424 | if (num_gh == 1) { | |
1425 | ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC); | |
1426 | return gfs2_glock_nq(ghs); | |
1427 | } | |
1428 | ||
1429 | e = kcalloc(num_gh, sizeof(struct gfs2_holder *), GFP_KERNEL); | |
1430 | if (!e) | |
1431 | return -ENOMEM; | |
1432 | ||
1433 | for (x = 0; x < num_gh; x++) { | |
1434 | ghs[x].gh_flags |= LM_FLAG_TRY | GL_ASYNC; | |
1435 | error = gfs2_glock_nq(&ghs[x]); | |
1436 | if (error) { | |
1437 | borked = 1; | |
1438 | serious = error; | |
1439 | num_gh = x; | |
1440 | break; | |
1441 | } | |
1442 | } | |
1443 | ||
1444 | for (x = 0; x < num_gh; x++) { | |
1445 | error = e[x] = glock_wait_internal(&ghs[x]); | |
1446 | if (error) { | |
1447 | borked = 1; | |
1448 | if (error != GLR_TRYFAILED && error != GLR_CANCELED) | |
1449 | serious = error; | |
1450 | } | |
1451 | } | |
1452 | ||
1453 | if (!borked) { | |
1454 | kfree(e); | |
1455 | return 0; | |
1456 | } | |
1457 | ||
1458 | for (x = 0; x < num_gh; x++) | |
1459 | if (!e[x]) | |
1460 | gfs2_glock_dq(&ghs[x]); | |
1461 | ||
1462 | if (serious) | |
1463 | error = serious; | |
1464 | else { | |
1465 | for (x = 0; x < num_gh; x++) | |
1466 | gfs2_holder_reinit(ghs[x].gh_state, ghs[x].gh_flags, | |
1467 | &ghs[x]); | |
1468 | error = nq_m_sync(num_gh, ghs, (struct gfs2_holder **)e); | |
1469 | } | |
1470 | ||
1471 | kfree(e); | |
1472 | ||
1473 | return error; | |
1474 | } | |
1475 | ||
1476 | /** | |
1477 | * gfs2_glock_dq_m - release multiple glocks | |
1478 | * @num_gh: the number of structures | |
1479 | * @ghs: an array of struct gfs2_holder structures | |
1480 | * | |
1481 | */ | |
1482 | ||
1483 | void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1484 | { | |
1485 | unsigned int x; | |
1486 | ||
1487 | for (x = 0; x < num_gh; x++) | |
1488 | gfs2_glock_dq(&ghs[x]); | |
1489 | } | |
1490 | ||
1491 | /** | |
1492 | * gfs2_glock_dq_uninit_m - release multiple glocks | |
1493 | * @num_gh: the number of structures | |
1494 | * @ghs: an array of struct gfs2_holder structures | |
1495 | * | |
1496 | */ | |
1497 | ||
1498 | void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs) | |
1499 | { | |
1500 | unsigned int x; | |
1501 | ||
1502 | for (x = 0; x < num_gh; x++) | |
1503 | gfs2_glock_dq_uninit(&ghs[x]); | |
1504 | } | |
1505 | ||
b3b94faa DT |
1506 | /** |
1507 | * gfs2_lvb_hold - attach a LVB from a glock | |
1508 | * @gl: The glock in question | |
1509 | * | |
1510 | */ | |
1511 | ||
1512 | int gfs2_lvb_hold(struct gfs2_glock *gl) | |
1513 | { | |
1514 | int error; | |
1515 | ||
1516 | gfs2_glmutex_lock(gl); | |
1517 | ||
1518 | if (!atomic_read(&gl->gl_lvb_count)) { | |
1519 | error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb); | |
1520 | if (error) { | |
1521 | gfs2_glmutex_unlock(gl); | |
1522 | return error; | |
1523 | } | |
1524 | gfs2_glock_hold(gl); | |
1525 | } | |
1526 | atomic_inc(&gl->gl_lvb_count); | |
1527 | ||
1528 | gfs2_glmutex_unlock(gl); | |
1529 | ||
1530 | return 0; | |
1531 | } | |
1532 | ||
1533 | /** | |
1534 | * gfs2_lvb_unhold - detach a LVB from a glock | |
1535 | * @gl: The glock in question | |
1536 | * | |
1537 | */ | |
1538 | ||
1539 | void gfs2_lvb_unhold(struct gfs2_glock *gl) | |
1540 | { | |
1541 | gfs2_glock_hold(gl); | |
1542 | gfs2_glmutex_lock(gl); | |
1543 | ||
1544 | gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0); | |
1545 | if (atomic_dec_and_test(&gl->gl_lvb_count)) { | |
1546 | gfs2_lm_unhold_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb); | |
1547 | gl->gl_lvb = NULL; | |
1548 | gfs2_glock_put(gl); | |
1549 | } | |
1550 | ||
1551 | gfs2_glmutex_unlock(gl); | |
1552 | gfs2_glock_put(gl); | |
1553 | } | |
1554 | ||
b3b94faa DT |
1555 | static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name, |
1556 | unsigned int state) | |
1557 | { | |
1558 | struct gfs2_glock *gl; | |
1559 | ||
1560 | gl = gfs2_glock_find(sdp, name); | |
1561 | if (!gl) | |
1562 | return; | |
1563 | ||
b3b94faa DT |
1564 | handle_callback(gl, state); |
1565 | ||
1566 | spin_lock(&gl->gl_spin); | |
1567 | run_queue(gl); | |
1568 | spin_unlock(&gl->gl_spin); | |
1569 | ||
1570 | gfs2_glock_put(gl); | |
1571 | } | |
1572 | ||
1573 | /** | |
1574 | * gfs2_glock_cb - Callback used by locking module | |
1c089c32 | 1575 | * @sdp: Pointer to the superblock |
b3b94faa DT |
1576 | * @type: Type of callback |
1577 | * @data: Type dependent data pointer | |
1578 | * | |
1579 | * Called by the locking module when it wants to tell us something. | |
1580 | * Either we need to drop a lock, one of our ASYNC requests completed, or | |
1581 | * a journal from another client needs to be recovered. | |
1582 | */ | |
1583 | ||
9b47c11d | 1584 | void gfs2_glock_cb(void *cb_data, unsigned int type, void *data) |
b3b94faa | 1585 | { |
9b47c11d | 1586 | struct gfs2_sbd *sdp = cb_data; |
b3b94faa | 1587 | |
b3b94faa DT |
1588 | switch (type) { |
1589 | case LM_CB_NEED_E: | |
e7f5c01c | 1590 | blocking_cb(sdp, data, LM_ST_UNLOCKED); |
b3b94faa DT |
1591 | return; |
1592 | ||
1593 | case LM_CB_NEED_D: | |
e7f5c01c | 1594 | blocking_cb(sdp, data, LM_ST_DEFERRED); |
b3b94faa DT |
1595 | return; |
1596 | ||
1597 | case LM_CB_NEED_S: | |
e7f5c01c | 1598 | blocking_cb(sdp, data, LM_ST_SHARED); |
b3b94faa DT |
1599 | return; |
1600 | ||
1601 | case LM_CB_ASYNC: { | |
e7f5c01c | 1602 | struct lm_async_cb *async = data; |
b3b94faa DT |
1603 | struct gfs2_glock *gl; |
1604 | ||
61be084e | 1605 | down_read(&gfs2_umount_flush_sem); |
b3b94faa DT |
1606 | gl = gfs2_glock_find(sdp, &async->lc_name); |
1607 | if (gfs2_assert_warn(sdp, gl)) | |
1608 | return; | |
1609 | if (!gfs2_assert_warn(sdp, gl->gl_req_bh)) | |
1610 | gl->gl_req_bh(gl, async->lc_ret); | |
1611 | gfs2_glock_put(gl); | |
61be084e | 1612 | up_read(&gfs2_umount_flush_sem); |
b3b94faa DT |
1613 | return; |
1614 | } | |
1615 | ||
1616 | case LM_CB_NEED_RECOVERY: | |
1617 | gfs2_jdesc_make_dirty(sdp, *(unsigned int *)data); | |
1618 | if (sdp->sd_recoverd_process) | |
1619 | wake_up_process(sdp->sd_recoverd_process); | |
1620 | return; | |
1621 | ||
1622 | case LM_CB_DROPLOCKS: | |
1623 | gfs2_gl_hash_clear(sdp, NO_WAIT); | |
1624 | gfs2_quota_scan(sdp); | |
1625 | return; | |
1626 | ||
1627 | default: | |
1628 | gfs2_assert_warn(sdp, 0); | |
1629 | return; | |
1630 | } | |
1631 | } | |
1632 | ||
b3b94faa DT |
1633 | /** |
1634 | * demote_ok - Check to see if it's ok to unlock a glock | |
1635 | * @gl: the glock | |
1636 | * | |
1637 | * Returns: 1 if it's ok | |
1638 | */ | |
1639 | ||
1640 | static int demote_ok(struct gfs2_glock *gl) | |
1641 | { | |
8fb4b536 | 1642 | const struct gfs2_glock_operations *glops = gl->gl_ops; |
b3b94faa DT |
1643 | int demote = 1; |
1644 | ||
1645 | if (test_bit(GLF_STICKY, &gl->gl_flags)) | |
1646 | demote = 0; | |
b3b94faa DT |
1647 | else if (glops->go_demote_ok) |
1648 | demote = glops->go_demote_ok(gl); | |
1649 | ||
1650 | return demote; | |
1651 | } | |
1652 | ||
1653 | /** | |
1654 | * gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list | |
1655 | * @gl: the glock | |
1656 | * | |
1657 | */ | |
1658 | ||
1659 | void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl) | |
1660 | { | |
1661 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1662 | ||
1663 | spin_lock(&sdp->sd_reclaim_lock); | |
1664 | if (list_empty(&gl->gl_reclaim)) { | |
1665 | gfs2_glock_hold(gl); | |
1666 | list_add(&gl->gl_reclaim, &sdp->sd_reclaim_list); | |
1667 | atomic_inc(&sdp->sd_reclaim_count); | |
1668 | } | |
1669 | spin_unlock(&sdp->sd_reclaim_lock); | |
1670 | ||
1671 | wake_up(&sdp->sd_reclaim_wq); | |
1672 | } | |
1673 | ||
1674 | /** | |
1675 | * gfs2_reclaim_glock - process the next glock on the filesystem's reclaim list | |
1676 | * @sdp: the filesystem | |
1677 | * | |
1678 | * Called from gfs2_glockd() glock reclaim daemon, or when promoting a | |
1679 | * different glock and we notice that there are a lot of glocks in the | |
1680 | * reclaim list. | |
1681 | * | |
1682 | */ | |
1683 | ||
1684 | void gfs2_reclaim_glock(struct gfs2_sbd *sdp) | |
1685 | { | |
1686 | struct gfs2_glock *gl; | |
1687 | ||
1688 | spin_lock(&sdp->sd_reclaim_lock); | |
1689 | if (list_empty(&sdp->sd_reclaim_list)) { | |
1690 | spin_unlock(&sdp->sd_reclaim_lock); | |
1691 | return; | |
1692 | } | |
1693 | gl = list_entry(sdp->sd_reclaim_list.next, | |
1694 | struct gfs2_glock, gl_reclaim); | |
1695 | list_del_init(&gl->gl_reclaim); | |
1696 | spin_unlock(&sdp->sd_reclaim_lock); | |
1697 | ||
1698 | atomic_dec(&sdp->sd_reclaim_count); | |
1699 | atomic_inc(&sdp->sd_reclaimed); | |
1700 | ||
1701 | if (gfs2_glmutex_trylock(gl)) { | |
12132933 | 1702 | if (list_empty(&gl->gl_holders) && |
50299965 | 1703 | gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl)) |
b3b94faa DT |
1704 | handle_callback(gl, LM_ST_UNLOCKED); |
1705 | gfs2_glmutex_unlock(gl); | |
1706 | } | |
1707 | ||
1708 | gfs2_glock_put(gl); | |
1709 | } | |
1710 | ||
1711 | /** | |
1712 | * examine_bucket - Call a function for glock in a hash bucket | |
1713 | * @examiner: the function | |
1714 | * @sdp: the filesystem | |
1715 | * @bucket: the bucket | |
1716 | * | |
1717 | * Returns: 1 if the bucket has entries | |
1718 | */ | |
1719 | ||
1720 | static int examine_bucket(glock_examiner examiner, struct gfs2_sbd *sdp, | |
37b2fa6a | 1721 | unsigned int hash) |
b3b94faa | 1722 | { |
24264434 SW |
1723 | struct gfs2_glock *gl, *prev = NULL; |
1724 | int has_entries = 0; | |
b6397893 | 1725 | struct hlist_head *head = &gl_hash_table[hash].hb_list; |
b3b94faa | 1726 | |
24264434 | 1727 | read_lock(gl_lock_addr(hash)); |
b6397893 SW |
1728 | /* Can't use hlist_for_each_entry - don't want prefetch here */ |
1729 | if (hlist_empty(head)) | |
24264434 | 1730 | goto out; |
b6397893 SW |
1731 | gl = list_entry(head->first, struct gfs2_glock, gl_list); |
1732 | while(1) { | |
24264434 | 1733 | if (gl->gl_sbd == sdp) { |
b3b94faa | 1734 | gfs2_glock_hold(gl); |
24264434 SW |
1735 | read_unlock(gl_lock_addr(hash)); |
1736 | if (prev) | |
1737 | gfs2_glock_put(prev); | |
1738 | prev = gl; | |
1739 | examiner(gl); | |
a8336344 | 1740 | has_entries = 1; |
24264434 | 1741 | read_lock(gl_lock_addr(hash)); |
b3b94faa | 1742 | } |
b6397893 SW |
1743 | if (gl->gl_list.next == NULL) |
1744 | break; | |
24264434 | 1745 | gl = list_entry(gl->gl_list.next, struct gfs2_glock, gl_list); |
b3b94faa | 1746 | } |
24264434 SW |
1747 | out: |
1748 | read_unlock(gl_lock_addr(hash)); | |
1749 | if (prev) | |
1750 | gfs2_glock_put(prev); | |
1751 | return has_entries; | |
b3b94faa DT |
1752 | } |
1753 | ||
1754 | /** | |
1755 | * scan_glock - look at a glock and see if we can reclaim it | |
1756 | * @gl: the glock to look at | |
1757 | * | |
1758 | */ | |
1759 | ||
1760 | static void scan_glock(struct gfs2_glock *gl) | |
1761 | { | |
b004157a | 1762 | if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) |
24264434 | 1763 | return; |
a2242db0 | 1764 | |
b3b94faa | 1765 | if (gfs2_glmutex_trylock(gl)) { |
12132933 | 1766 | if (list_empty(&gl->gl_holders) && |
24264434 | 1767 | gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl)) |
b3b94faa | 1768 | goto out_schedule; |
b3b94faa DT |
1769 | gfs2_glmutex_unlock(gl); |
1770 | } | |
b3b94faa DT |
1771 | return; |
1772 | ||
627add2d | 1773 | out_schedule: |
b3b94faa DT |
1774 | gfs2_glmutex_unlock(gl); |
1775 | gfs2_glock_schedule_for_reclaim(gl); | |
b3b94faa DT |
1776 | } |
1777 | ||
1778 | /** | |
1779 | * gfs2_scand_internal - Look for glocks and inodes to toss from memory | |
1780 | * @sdp: the filesystem | |
1781 | * | |
1782 | */ | |
1783 | ||
1784 | void gfs2_scand_internal(struct gfs2_sbd *sdp) | |
1785 | { | |
1786 | unsigned int x; | |
1787 | ||
94610610 | 1788 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) |
37b2fa6a | 1789 | examine_bucket(scan_glock, sdp, x); |
b3b94faa DT |
1790 | } |
1791 | ||
1792 | /** | |
1793 | * clear_glock - look at a glock and see if we can free it from glock cache | |
1794 | * @gl: the glock to look at | |
1795 | * | |
1796 | */ | |
1797 | ||
1798 | static void clear_glock(struct gfs2_glock *gl) | |
1799 | { | |
1800 | struct gfs2_sbd *sdp = gl->gl_sbd; | |
1801 | int released; | |
1802 | ||
1803 | spin_lock(&sdp->sd_reclaim_lock); | |
1804 | if (!list_empty(&gl->gl_reclaim)) { | |
1805 | list_del_init(&gl->gl_reclaim); | |
1806 | atomic_dec(&sdp->sd_reclaim_count); | |
190562bd | 1807 | spin_unlock(&sdp->sd_reclaim_lock); |
b3b94faa DT |
1808 | released = gfs2_glock_put(gl); |
1809 | gfs2_assert(sdp, !released); | |
190562bd SW |
1810 | } else { |
1811 | spin_unlock(&sdp->sd_reclaim_lock); | |
b3b94faa | 1812 | } |
b3b94faa DT |
1813 | |
1814 | if (gfs2_glmutex_trylock(gl)) { | |
90101c31 | 1815 | if (list_empty(&gl->gl_holders) && |
b3b94faa DT |
1816 | gl->gl_state != LM_ST_UNLOCKED) |
1817 | handle_callback(gl, LM_ST_UNLOCKED); | |
b3b94faa DT |
1818 | gfs2_glmutex_unlock(gl); |
1819 | } | |
b3b94faa DT |
1820 | } |
1821 | ||
1822 | /** | |
1823 | * gfs2_gl_hash_clear - Empty out the glock hash table | |
1824 | * @sdp: the filesystem | |
1825 | * @wait: wait until it's all gone | |
1826 | * | |
1827 | * Called when unmounting the filesystem, or when inter-node lock manager | |
1828 | * requests DROPLOCKS because it is running out of capacity. | |
1829 | */ | |
1830 | ||
1831 | void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait) | |
1832 | { | |
1833 | unsigned long t; | |
1834 | unsigned int x; | |
1835 | int cont; | |
1836 | ||
1837 | t = jiffies; | |
1838 | ||
1839 | for (;;) { | |
1840 | cont = 0; | |
24264434 | 1841 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { |
907b9bce | 1842 | if (examine_bucket(clear_glock, sdp, x)) |
b3b94faa | 1843 | cont = 1; |
24264434 | 1844 | } |
b3b94faa DT |
1845 | |
1846 | if (!wait || !cont) | |
1847 | break; | |
1848 | ||
1849 | if (time_after_eq(jiffies, | |
1850 | t + gfs2_tune_get(sdp, gt_stall_secs) * HZ)) { | |
1851 | fs_warn(sdp, "Unmount seems to be stalled. " | |
1852 | "Dumping lock state...\n"); | |
1853 | gfs2_dump_lockstate(sdp); | |
1854 | t = jiffies; | |
1855 | } | |
1856 | ||
61be084e | 1857 | down_write(&gfs2_umount_flush_sem); |
b3b94faa | 1858 | invalidate_inodes(sdp->sd_vfs); |
61be084e | 1859 | up_write(&gfs2_umount_flush_sem); |
fd88de56 | 1860 | msleep(10); |
b3b94faa DT |
1861 | } |
1862 | } | |
1863 | ||
1864 | /* | |
1865 | * Diagnostic routines to help debug distributed deadlock | |
1866 | */ | |
1867 | ||
1868 | /** | |
1869 | * dump_holder - print information about a glock holder | |
1870 | * @str: a string naming the type of holder | |
1871 | * @gh: the glock holder | |
1872 | * | |
1873 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
1874 | */ | |
1875 | ||
7c52b166 RP |
1876 | static int dump_holder(struct glock_iter *gi, char *str, |
1877 | struct gfs2_holder *gh) | |
b3b94faa DT |
1878 | { |
1879 | unsigned int x; | |
b3b94faa | 1880 | |
7c52b166 RP |
1881 | print_dbg(gi, " %s\n", str); |
1882 | print_dbg(gi, " owner = %ld\n", | |
b3b94faa | 1883 | (gh->gh_owner) ? (long)gh->gh_owner->pid : -1); |
7c52b166 RP |
1884 | print_dbg(gi, " gh_state = %u\n", gh->gh_state); |
1885 | print_dbg(gi, " gh_flags ="); | |
b3b94faa DT |
1886 | for (x = 0; x < 32; x++) |
1887 | if (gh->gh_flags & (1 << x)) | |
7c52b166 RP |
1888 | print_dbg(gi, " %u", x); |
1889 | print_dbg(gi, " \n"); | |
1890 | print_dbg(gi, " error = %d\n", gh->gh_error); | |
1891 | print_dbg(gi, " gh_iflags ="); | |
b3b94faa DT |
1892 | for (x = 0; x < 32; x++) |
1893 | if (test_bit(x, &gh->gh_iflags)) | |
7c52b166 RP |
1894 | print_dbg(gi, " %u", x); |
1895 | print_dbg(gi, " \n"); | |
1896 | if (gi) | |
1897 | print_dbg(gi, " initialized at: 0x%x\n", gh->gh_ip); | |
1898 | else | |
1899 | print_symbol(KERN_INFO " initialized at: %s\n", gh->gh_ip); | |
b3b94faa | 1900 | |
7c52b166 | 1901 | return 0; |
b3b94faa DT |
1902 | } |
1903 | ||
1904 | /** | |
1905 | * dump_inode - print information about an inode | |
1906 | * @ip: the inode | |
1907 | * | |
1908 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
1909 | */ | |
1910 | ||
7c52b166 | 1911 | static int dump_inode(struct glock_iter *gi, struct gfs2_inode *ip) |
b3b94faa DT |
1912 | { |
1913 | unsigned int x; | |
b3b94faa | 1914 | |
7c52b166 RP |
1915 | print_dbg(gi, " Inode:\n"); |
1916 | print_dbg(gi, " num = %llu/%llu\n", | |
1917 | ip->i_num.no_formal_ino, ip->i_num.no_addr); | |
1918 | print_dbg(gi, " type = %u\n", IF2DT(ip->i_inode.i_mode)); | |
1919 | print_dbg(gi, " i_flags ="); | |
b3b94faa DT |
1920 | for (x = 0; x < 32; x++) |
1921 | if (test_bit(x, &ip->i_flags)) | |
7c52b166 RP |
1922 | print_dbg(gi, " %u", x); |
1923 | print_dbg(gi, " \n"); | |
1924 | return 0; | |
b3b94faa DT |
1925 | } |
1926 | ||
1927 | /** | |
1928 | * dump_glock - print information about a glock | |
1929 | * @gl: the glock | |
1930 | * @count: where we are in the buffer | |
1931 | * | |
1932 | * Returns: 0 on success, -ENOBUFS when we run out of space | |
1933 | */ | |
1934 | ||
7c52b166 | 1935 | static int dump_glock(struct glock_iter *gi, struct gfs2_glock *gl) |
b3b94faa DT |
1936 | { |
1937 | struct gfs2_holder *gh; | |
1938 | unsigned int x; | |
1939 | int error = -ENOBUFS; | |
1940 | ||
1941 | spin_lock(&gl->gl_spin); | |
1942 | ||
7c52b166 RP |
1943 | print_dbg(gi, "Glock 0x%p (%u, %llu)\n", gl, gl->gl_name.ln_type, |
1944 | (unsigned long long)gl->gl_name.ln_number); | |
1945 | print_dbg(gi, " gl_flags ="); | |
85d1da67 | 1946 | for (x = 0; x < 32; x++) { |
b3b94faa | 1947 | if (test_bit(x, &gl->gl_flags)) |
7c52b166 RP |
1948 | print_dbg(gi, " %u", x); |
1949 | } | |
1950 | print_dbg(gi, " \n"); | |
1951 | print_dbg(gi, " gl_ref = %d\n", atomic_read(&gl->gl_ref)); | |
1952 | print_dbg(gi, " gl_state = %u\n", gl->gl_state); | |
1953 | print_dbg(gi, " gl_owner = %s\n", gl->gl_owner->comm); | |
1954 | print_dbg(gi, " gl_ip = %lu\n", gl->gl_ip); | |
1955 | print_dbg(gi, " req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no"); | |
1956 | print_dbg(gi, " req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no"); | |
1957 | print_dbg(gi, " lvb_count = %d\n", atomic_read(&gl->gl_lvb_count)); | |
1958 | print_dbg(gi, " object = %s\n", (gl->gl_object) ? "yes" : "no"); | |
1959 | print_dbg(gi, " le = %s\n", | |
b3b94faa | 1960 | (list_empty(&gl->gl_le.le_list)) ? "no" : "yes"); |
7c52b166 RP |
1961 | print_dbg(gi, " reclaim = %s\n", |
1962 | (list_empty(&gl->gl_reclaim)) ? "no" : "yes"); | |
b3b94faa | 1963 | if (gl->gl_aspace) |
7c52b166 RP |
1964 | print_dbg(gi, " aspace = 0x%p nrpages = %lu\n", gl->gl_aspace, |
1965 | gl->gl_aspace->i_mapping->nrpages); | |
b3b94faa | 1966 | else |
7c52b166 RP |
1967 | print_dbg(gi, " aspace = no\n"); |
1968 | print_dbg(gi, " ail = %d\n", atomic_read(&gl->gl_ail_count)); | |
b3b94faa | 1969 | if (gl->gl_req_gh) { |
7c52b166 | 1970 | error = dump_holder(gi, "Request", gl->gl_req_gh); |
b3b94faa DT |
1971 | if (error) |
1972 | goto out; | |
1973 | } | |
1974 | list_for_each_entry(gh, &gl->gl_holders, gh_list) { | |
7c52b166 | 1975 | error = dump_holder(gi, "Holder", gh); |
b3b94faa DT |
1976 | if (error) |
1977 | goto out; | |
1978 | } | |
1979 | list_for_each_entry(gh, &gl->gl_waiters1, gh_list) { | |
7c52b166 | 1980 | error = dump_holder(gi, "Waiter1", gh); |
b3b94faa DT |
1981 | if (error) |
1982 | goto out; | |
1983 | } | |
1984 | list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { | |
7c52b166 | 1985 | error = dump_holder(gi, "Waiter2", gh); |
b3b94faa DT |
1986 | if (error) |
1987 | goto out; | |
1988 | } | |
1989 | list_for_each_entry(gh, &gl->gl_waiters3, gh_list) { | |
7c52b166 | 1990 | error = dump_holder(gi, "Waiter3", gh); |
b3b94faa DT |
1991 | if (error) |
1992 | goto out; | |
1993 | } | |
5c676f6d | 1994 | if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) { |
b3b94faa | 1995 | if (!test_bit(GLF_LOCK, &gl->gl_flags) && |
7c52b166 RP |
1996 | list_empty(&gl->gl_holders)) { |
1997 | error = dump_inode(gi, gl->gl_object); | |
b3b94faa DT |
1998 | if (error) |
1999 | goto out; | |
2000 | } else { | |
2001 | error = -ENOBUFS; | |
7c52b166 | 2002 | print_dbg(gi, " Inode: busy\n"); |
b3b94faa DT |
2003 | } |
2004 | } | |
2005 | ||
2006 | error = 0; | |
2007 | ||
a91ea69f | 2008 | out: |
b3b94faa | 2009 | spin_unlock(&gl->gl_spin); |
b3b94faa DT |
2010 | return error; |
2011 | } | |
2012 | ||
2013 | /** | |
2014 | * gfs2_dump_lockstate - print out the current lockstate | |
2015 | * @sdp: the filesystem | |
2016 | * @ub: the buffer to copy the information into | |
2017 | * | |
2018 | * If @ub is NULL, dump the lockstate to the console. | |
2019 | * | |
2020 | */ | |
2021 | ||
08bc2dbc | 2022 | static int gfs2_dump_lockstate(struct gfs2_sbd *sdp) |
b3b94faa | 2023 | { |
b3b94faa | 2024 | struct gfs2_glock *gl; |
b6397893 | 2025 | struct hlist_node *h; |
b3b94faa DT |
2026 | unsigned int x; |
2027 | int error = 0; | |
2028 | ||
2029 | for (x = 0; x < GFS2_GL_HASH_SIZE; x++) { | |
b3b94faa | 2030 | |
087efdd3 | 2031 | read_lock(gl_lock_addr(x)); |
b3b94faa | 2032 | |
b6397893 | 2033 | hlist_for_each_entry(gl, h, &gl_hash_table[x].hb_list, gl_list) { |
85d1da67 SW |
2034 | if (gl->gl_sbd != sdp) |
2035 | continue; | |
b3b94faa | 2036 | |
7c52b166 | 2037 | error = dump_glock(NULL, gl); |
b3b94faa DT |
2038 | if (error) |
2039 | break; | |
2040 | } | |
2041 | ||
087efdd3 | 2042 | read_unlock(gl_lock_addr(x)); |
b3b94faa DT |
2043 | |
2044 | if (error) | |
2045 | break; | |
2046 | } | |
2047 | ||
2048 | ||
2049 | return error; | |
2050 | } | |
2051 | ||
85d1da67 SW |
2052 | int __init gfs2_glock_init(void) |
2053 | { | |
2054 | unsigned i; | |
2055 | for(i = 0; i < GFS2_GL_HASH_SIZE; i++) { | |
b6397893 | 2056 | INIT_HLIST_HEAD(&gl_hash_table[i].hb_list); |
85d1da67 | 2057 | } |
087efdd3 SW |
2058 | #ifdef GL_HASH_LOCK_SZ |
2059 | for(i = 0; i < GL_HASH_LOCK_SZ; i++) { | |
2060 | rwlock_init(&gl_hash_locks[i]); | |
2061 | } | |
2062 | #endif | |
85d1da67 SW |
2063 | return 0; |
2064 | } | |
2065 | ||
7c52b166 RP |
2066 | static int gfs2_glock_iter_next(struct glock_iter *gi) |
2067 | { | |
2068 | while (1) { | |
2069 | if (!gi->hb_list) { /* If we don't have a hash bucket yet */ | |
2070 | gi->hb_list = &gl_hash_table[gi->hash].hb_list; | |
2071 | if (hlist_empty(gi->hb_list)) { | |
2072 | gi->hash++; | |
2073 | gi->hb_list = NULL; | |
2074 | if (gi->hash >= GFS2_GL_HASH_SIZE) | |
2075 | return 1; | |
2076 | else | |
2077 | continue; | |
2078 | } | |
2079 | if (!hlist_empty(gi->hb_list)) { | |
2080 | gi->gl = list_entry(gi->hb_list->first, | |
2081 | struct gfs2_glock, | |
2082 | gl_list); | |
2083 | } | |
2084 | } else { | |
2085 | if (gi->gl->gl_list.next == NULL) { | |
2086 | gi->hash++; | |
2087 | gi->hb_list = NULL; | |
2088 | continue; | |
2089 | } | |
2090 | gi->gl = list_entry(gi->gl->gl_list.next, | |
2091 | struct gfs2_glock, gl_list); | |
2092 | } | |
2093 | if (gi->gl) | |
2094 | break; | |
2095 | } | |
2096 | return 0; | |
2097 | } | |
2098 | ||
2099 | static void gfs2_glock_iter_free(struct glock_iter *gi) | |
2100 | { | |
2101 | kfree(gi); | |
2102 | } | |
2103 | ||
2104 | static struct glock_iter *gfs2_glock_iter_init(struct gfs2_sbd *sdp) | |
2105 | { | |
2106 | struct glock_iter *gi; | |
2107 | ||
2108 | gi = kmalloc(sizeof (*gi), GFP_KERNEL); | |
2109 | if (!gi) | |
2110 | return NULL; | |
2111 | ||
2112 | gi->sdp = sdp; | |
2113 | gi->hash = 0; | |
2114 | gi->gl = NULL; | |
2115 | gi->hb_list = NULL; | |
2116 | gi->seq = NULL; | |
2117 | memset(gi->string, 0, sizeof(gi->string)); | |
2118 | ||
2119 | if (gfs2_glock_iter_next(gi)) { | |
2120 | gfs2_glock_iter_free(gi); | |
2121 | return NULL; | |
2122 | } | |
2123 | ||
2124 | return gi; | |
2125 | } | |
2126 | ||
2127 | static void *gfs2_glock_seq_start(struct seq_file *file, loff_t *pos) | |
2128 | { | |
2129 | struct glock_iter *gi; | |
2130 | loff_t n = *pos; | |
2131 | ||
2132 | gi = gfs2_glock_iter_init(file->private); | |
2133 | if (!gi) | |
2134 | return NULL; | |
2135 | ||
2136 | while (n--) { | |
2137 | if (gfs2_glock_iter_next(gi)) { | |
2138 | gfs2_glock_iter_free(gi); | |
2139 | return NULL; | |
2140 | } | |
2141 | } | |
2142 | ||
2143 | return gi; | |
2144 | } | |
2145 | ||
2146 | static void *gfs2_glock_seq_next(struct seq_file *file, void *iter_ptr, | |
2147 | loff_t *pos) | |
2148 | { | |
2149 | struct glock_iter *gi = iter_ptr; | |
2150 | ||
2151 | (*pos)++; | |
2152 | ||
2153 | if (gfs2_glock_iter_next(gi)) { | |
2154 | gfs2_glock_iter_free(gi); | |
2155 | return NULL; | |
2156 | } | |
2157 | ||
2158 | return gi; | |
2159 | } | |
2160 | ||
2161 | static void gfs2_glock_seq_stop(struct seq_file *file, void *iter_ptr) | |
2162 | { | |
2163 | /* nothing for now */ | |
2164 | } | |
2165 | ||
2166 | static int gfs2_glock_seq_show(struct seq_file *file, void *iter_ptr) | |
2167 | { | |
2168 | struct glock_iter *gi = iter_ptr; | |
2169 | ||
2170 | gi->seq = file; | |
2171 | dump_glock(gi, gi->gl); | |
2172 | ||
2173 | return 0; | |
2174 | } | |
2175 | ||
2176 | static struct seq_operations gfs2_glock_seq_ops = { | |
2177 | .start = gfs2_glock_seq_start, | |
2178 | .next = gfs2_glock_seq_next, | |
2179 | .stop = gfs2_glock_seq_stop, | |
2180 | .show = gfs2_glock_seq_show, | |
2181 | }; | |
2182 | ||
2183 | static int gfs2_debugfs_open(struct inode *inode, struct file *file) | |
2184 | { | |
2185 | struct seq_file *seq; | |
2186 | int ret; | |
2187 | ||
2188 | ret = seq_open(file, &gfs2_glock_seq_ops); | |
2189 | if (ret) | |
2190 | return ret; | |
2191 | ||
2192 | seq = file->private_data; | |
2193 | seq->private = inode->i_private; | |
2194 | ||
2195 | return 0; | |
2196 | } | |
2197 | ||
2198 | static const struct file_operations gfs2_debug_fops = { | |
2199 | .owner = THIS_MODULE, | |
2200 | .open = gfs2_debugfs_open, | |
2201 | .read = seq_read, | |
2202 | .llseek = seq_lseek, | |
2203 | .release = seq_release | |
2204 | }; | |
2205 | ||
2206 | int gfs2_create_debugfs_file(struct gfs2_sbd *sdp) | |
2207 | { | |
2208 | sdp->debugfs_dentry = debugfs_create_file(sdp->sd_table_name, | |
2209 | S_IFREG | S_IRUGO, | |
2210 | gfs2_root, sdp, | |
2211 | &gfs2_debug_fops); | |
2212 | if (!sdp->debugfs_dentry) | |
2213 | return -ENOMEM; | |
2214 | ||
2215 | return 0; | |
2216 | } | |
2217 | ||
2218 | void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp) | |
2219 | { | |
5c7342d8 | 2220 | if (sdp && sdp->debugfs_dentry) |
7c52b166 RP |
2221 | debugfs_remove(sdp->debugfs_dentry); |
2222 | } | |
2223 | ||
2224 | int gfs2_register_debugfs(void) | |
2225 | { | |
2226 | gfs2_root = debugfs_create_dir("gfs2", NULL); | |
2227 | return gfs2_root ? 0 : -ENOMEM; | |
2228 | } | |
2229 | ||
2230 | void gfs2_unregister_debugfs(void) | |
2231 | { | |
2232 | debugfs_remove(gfs2_root); | |
2233 | } |