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-rw-r--r--fs/fscache/cache.c34
-rw-r--r--fs/fscache/cookie.c93
-rw-r--r--fs/fscache/fsdef.c1
-rw-r--r--fs/fscache/internal.h11
-rw-r--r--fs/fscache/main.c11
-rw-r--r--fs/fscache/netfs.c1
-rw-r--r--fs/fscache/object-list.c103
-rw-r--r--fs/fscache/object.c1106
-rw-r--r--fs/fscache/operation.c37
-rw-r--r--fs/fscache/page.c65
10 files changed, 738 insertions, 724 deletions
diff --git a/fs/fscache/cache.c b/fs/fscache/cache.c
index b52aed1dca97..f7cff367db7f 100644
--- a/fs/fscache/cache.c
+++ b/fs/fscache/cache.c
@@ -115,7 +115,7 @@ struct fscache_cache *fscache_select_cache_for_object(
115 struct fscache_object, cookie_link); 115 struct fscache_object, cookie_link);
116 116
117 cache = object->cache; 117 cache = object->cache;
118 if (object->state >= FSCACHE_OBJECT_DYING || 118 if (fscache_object_is_dying(object) ||
119 test_bit(FSCACHE_IOERROR, &cache->flags)) 119 test_bit(FSCACHE_IOERROR, &cache->flags))
120 cache = NULL; 120 cache = NULL;
121 121
@@ -224,8 +224,10 @@ int fscache_add_cache(struct fscache_cache *cache,
224 BUG_ON(!ifsdef); 224 BUG_ON(!ifsdef);
225 225
226 cache->flags = 0; 226 cache->flags = 0;
227 ifsdef->event_mask = ULONG_MAX & ~(1 << FSCACHE_OBJECT_EV_CLEARED); 227 ifsdef->event_mask =
228 ifsdef->state = FSCACHE_OBJECT_ACTIVE; 228 ((1 << NR_FSCACHE_OBJECT_EVENTS) - 1) &
229 ~(1 << FSCACHE_OBJECT_EV_CLEARED);
230 __set_bit(FSCACHE_OBJECT_IS_AVAILABLE, &ifsdef->flags);
229 231
230 if (!tagname) 232 if (!tagname)
231 tagname = cache->identifier; 233 tagname = cache->identifier;
@@ -330,25 +332,25 @@ static void fscache_withdraw_all_objects(struct fscache_cache *cache,
330{ 332{
331 struct fscache_object *object; 333 struct fscache_object *object;
332 334
333 spin_lock(&cache->object_list_lock);
334
335 while (!list_empty(&cache->object_list)) { 335 while (!list_empty(&cache->object_list)) {
336 object = list_entry(cache->object_list.next, 336 spin_lock(&cache->object_list_lock);
337 struct fscache_object, cache_link);
338 list_move_tail(&object->cache_link, dying_objects);
339 337
340 _debug("withdraw %p", object->cookie); 338 if (!list_empty(&cache->object_list)) {
339 object = list_entry(cache->object_list.next,
340 struct fscache_object, cache_link);
341 list_move_tail(&object->cache_link, dying_objects);
341 342
342 spin_lock(&object->lock); 343 _debug("withdraw %p", object->cookie);
343 spin_unlock(&cache->object_list_lock); 344
344 fscache_raise_event(object, FSCACHE_OBJECT_EV_WITHDRAW); 345 /* This must be done under object_list_lock to prevent
345 spin_unlock(&object->lock); 346 * a race with fscache_drop_object().
347 */
348 fscache_raise_event(object, FSCACHE_OBJECT_EV_KILL);
349 }
346 350
351 spin_unlock(&cache->object_list_lock);
347 cond_resched(); 352 cond_resched();
348 spin_lock(&cache->object_list_lock);
349 } 353 }
350
351 spin_unlock(&cache->object_list_lock);
352} 354}
353 355
354/** 356/**
diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c
index e2cba1f60c21..0e91a3c9fdb2 100644
--- a/fs/fscache/cookie.c
+++ b/fs/fscache/cookie.c
@@ -95,6 +95,11 @@ struct fscache_cookie *__fscache_acquire_cookie(
95 atomic_set(&cookie->usage, 1); 95 atomic_set(&cookie->usage, 1);
96 atomic_set(&cookie->n_children, 0); 96 atomic_set(&cookie->n_children, 0);
97 97
98 /* We keep the active count elevated until relinquishment to prevent an
99 * attempt to wake up every time the object operations queue quiesces.
100 */
101 atomic_set(&cookie->n_active, 1);
102
98 atomic_inc(&parent->usage); 103 atomic_inc(&parent->usage);
99 atomic_inc(&parent->n_children); 104 atomic_inc(&parent->n_children);
100 105
@@ -177,7 +182,6 @@ static int fscache_acquire_non_index_cookie(struct fscache_cookie *cookie)
177 182
178 cookie->flags = 183 cookie->flags =
179 (1 << FSCACHE_COOKIE_LOOKING_UP) | 184 (1 << FSCACHE_COOKIE_LOOKING_UP) |
180 (1 << FSCACHE_COOKIE_CREATING) |
181 (1 << FSCACHE_COOKIE_NO_DATA_YET); 185 (1 << FSCACHE_COOKIE_NO_DATA_YET);
182 186
183 /* ask the cache to allocate objects for this cookie and its parent 187 /* ask the cache to allocate objects for this cookie and its parent
@@ -205,7 +209,7 @@ static int fscache_acquire_non_index_cookie(struct fscache_cookie *cookie)
205 209
206 /* initiate the process of looking up all the objects in the chain 210 /* initiate the process of looking up all the objects in the chain
207 * (done by fscache_initialise_object()) */ 211 * (done by fscache_initialise_object()) */
208 fscache_enqueue_object(object); 212 fscache_raise_event(object, FSCACHE_OBJECT_EV_NEW_CHILD);
209 213
210 spin_unlock(&cookie->lock); 214 spin_unlock(&cookie->lock);
211 215
@@ -285,7 +289,7 @@ static int fscache_alloc_object(struct fscache_cache *cache,
285 289
286object_already_extant: 290object_already_extant:
287 ret = -ENOBUFS; 291 ret = -ENOBUFS;
288 if (object->state >= FSCACHE_OBJECT_DYING) { 292 if (fscache_object_is_dead(object)) {
289 spin_unlock(&cookie->lock); 293 spin_unlock(&cookie->lock);
290 goto error; 294 goto error;
291 } 295 }
@@ -321,7 +325,7 @@ static int fscache_attach_object(struct fscache_cookie *cookie,
321 ret = -EEXIST; 325 ret = -EEXIST;
322 hlist_for_each_entry(p, &cookie->backing_objects, cookie_link) { 326 hlist_for_each_entry(p, &cookie->backing_objects, cookie_link) {
323 if (p->cache == object->cache) { 327 if (p->cache == object->cache) {
324 if (p->state >= FSCACHE_OBJECT_DYING) 328 if (fscache_object_is_dying(p))
325 ret = -ENOBUFS; 329 ret = -ENOBUFS;
326 goto cant_attach_object; 330 goto cant_attach_object;
327 } 331 }
@@ -332,7 +336,7 @@ static int fscache_attach_object(struct fscache_cookie *cookie,
332 hlist_for_each_entry(p, &cookie->parent->backing_objects, 336 hlist_for_each_entry(p, &cookie->parent->backing_objects,
333 cookie_link) { 337 cookie_link) {
334 if (p->cache == object->cache) { 338 if (p->cache == object->cache) {
335 if (p->state >= FSCACHE_OBJECT_DYING) { 339 if (fscache_object_is_dying(p)) {
336 ret = -ENOBUFS; 340 ret = -ENOBUFS;
337 spin_unlock(&cookie->parent->lock); 341 spin_unlock(&cookie->parent->lock);
338 goto cant_attach_object; 342 goto cant_attach_object;
@@ -400,7 +404,7 @@ void __fscache_invalidate(struct fscache_cookie *cookie)
400 object = hlist_entry(cookie->backing_objects.first, 404 object = hlist_entry(cookie->backing_objects.first,
401 struct fscache_object, 405 struct fscache_object,
402 cookie_link); 406 cookie_link);
403 if (object->state < FSCACHE_OBJECT_DYING) 407 if (fscache_object_is_live(object))
404 fscache_raise_event( 408 fscache_raise_event(
405 object, FSCACHE_OBJECT_EV_INVALIDATE); 409 object, FSCACHE_OBJECT_EV_INVALIDATE);
406 } 410 }
@@ -467,9 +471,7 @@ EXPORT_SYMBOL(__fscache_update_cookie);
467 */ 471 */
468void __fscache_relinquish_cookie(struct fscache_cookie *cookie, int retire) 472void __fscache_relinquish_cookie(struct fscache_cookie *cookie, int retire)
469{ 473{
470 struct fscache_cache *cache;
471 struct fscache_object *object; 474 struct fscache_object *object;
472 unsigned long event;
473 475
474 fscache_stat(&fscache_n_relinquishes); 476 fscache_stat(&fscache_n_relinquishes);
475 if (retire) 477 if (retire)
@@ -481,8 +483,11 @@ void __fscache_relinquish_cookie(struct fscache_cookie *cookie, int retire)
481 return; 483 return;
482 } 484 }
483 485
484 _enter("%p{%s,%p},%d", 486 _enter("%p{%s,%p,%d},%d",
485 cookie, cookie->def->name, cookie->netfs_data, retire); 487 cookie, cookie->def->name, cookie->netfs_data,
488 atomic_read(&cookie->n_active), retire);
489
490 ASSERTCMP(atomic_read(&cookie->n_active), >, 0);
486 491
487 if (atomic_read(&cookie->n_children) != 0) { 492 if (atomic_read(&cookie->n_children) != 0) {
488 printk(KERN_ERR "FS-Cache: Cookie '%s' still has children\n", 493 printk(KERN_ERR "FS-Cache: Cookie '%s' still has children\n",
@@ -490,62 +495,28 @@ void __fscache_relinquish_cookie(struct fscache_cookie *cookie, int retire)
490 BUG(); 495 BUG();
491 } 496 }
492 497
493 /* wait for the cookie to finish being instantiated (or to fail) */ 498 /* No further netfs-accessing operations on this cookie permitted */
494 if (test_bit(FSCACHE_COOKIE_CREATING, &cookie->flags)) { 499 set_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags);
495 fscache_stat(&fscache_n_relinquishes_waitcrt); 500 if (retire)
496 wait_on_bit(&cookie->flags, FSCACHE_COOKIE_CREATING, 501 set_bit(FSCACHE_COOKIE_RETIRED, &cookie->flags);
497 fscache_wait_bit, TASK_UNINTERRUPTIBLE);
498 }
499
500 event = retire ? FSCACHE_OBJECT_EV_RETIRE : FSCACHE_OBJECT_EV_RELEASE;
501 502
502try_again:
503 spin_lock(&cookie->lock); 503 spin_lock(&cookie->lock);
504 504 hlist_for_each_entry(object, &cookie->backing_objects, cookie_link) {
505 /* break links with all the active objects */ 505 fscache_raise_event(object, FSCACHE_OBJECT_EV_KILL);
506 while (!hlist_empty(&cookie->backing_objects)) {
507 int n_reads;
508 object = hlist_entry(cookie->backing_objects.first,
509 struct fscache_object,
510 cookie_link);
511
512 _debug("RELEASE OBJ%x", object->debug_id);
513
514 set_bit(FSCACHE_COOKIE_WAITING_ON_READS, &cookie->flags);
515 n_reads = atomic_read(&object->n_reads);
516 if (n_reads) {
517 int n_ops = object->n_ops;
518 int n_in_progress = object->n_in_progress;
519 spin_unlock(&cookie->lock);
520 printk(KERN_ERR "FS-Cache:"
521 " Cookie '%s' still has %d outstanding reads (%d,%d)\n",
522 cookie->def->name,
523 n_reads, n_ops, n_in_progress);
524 wait_on_bit(&cookie->flags, FSCACHE_COOKIE_WAITING_ON_READS,
525 fscache_wait_bit, TASK_UNINTERRUPTIBLE);
526 printk("Wait finished\n");
527 goto try_again;
528 }
529
530 /* detach each cache object from the object cookie */
531 spin_lock(&object->lock);
532 hlist_del_init(&object->cookie_link);
533
534 cache = object->cache;
535 object->cookie = NULL;
536 fscache_raise_event(object, event);
537 spin_unlock(&object->lock);
538
539 if (atomic_dec_and_test(&cookie->usage))
540 /* the cookie refcount shouldn't be reduced to 0 yet */
541 BUG();
542 } 506 }
507 spin_unlock(&cookie->lock);
543 508
544 /* detach pointers back to the netfs */ 509 /* Wait for cessation of activity requiring access to the netfs (when
510 * n_active reaches 0).
511 */
512 if (!atomic_dec_and_test(&cookie->n_active))
513 wait_on_atomic_t(&cookie->n_active, fscache_wait_atomic_t,
514 TASK_UNINTERRUPTIBLE);
515
516 /* Clear pointers back to the netfs */
545 cookie->netfs_data = NULL; 517 cookie->netfs_data = NULL;
546 cookie->def = NULL; 518 cookie->def = NULL;
547 519 BUG_ON(cookie->stores.rnode);
548 spin_unlock(&cookie->lock);
549 520
550 if (cookie->parent) { 521 if (cookie->parent) {
551 ASSERTCMP(atomic_read(&cookie->parent->usage), >, 0); 522 ASSERTCMP(atomic_read(&cookie->parent->usage), >, 0);
@@ -553,7 +524,7 @@ try_again:
553 atomic_dec(&cookie->parent->n_children); 524 atomic_dec(&cookie->parent->n_children);
554 } 525 }
555 526
556 /* finally dispose of the cookie */ 527 /* Dispose of the netfs's link to the cookie */
557 ASSERTCMP(atomic_read(&cookie->usage), >, 0); 528 ASSERTCMP(atomic_read(&cookie->usage), >, 0);
558 fscache_cookie_put(cookie); 529 fscache_cookie_put(cookie);
559 530
diff --git a/fs/fscache/fsdef.c b/fs/fscache/fsdef.c
index f5b4baee7352..10a2ade0bdf8 100644
--- a/fs/fscache/fsdef.c
+++ b/fs/fscache/fsdef.c
@@ -55,6 +55,7 @@ static struct fscache_cookie_def fscache_fsdef_index_def = {
55 55
56struct fscache_cookie fscache_fsdef_index = { 56struct fscache_cookie fscache_fsdef_index = {
57 .usage = ATOMIC_INIT(1), 57 .usage = ATOMIC_INIT(1),
58 .n_active = ATOMIC_INIT(1),
58 .lock = __SPIN_LOCK_UNLOCKED(fscache_fsdef_index.lock), 59 .lock = __SPIN_LOCK_UNLOCKED(fscache_fsdef_index.lock),
59 .backing_objects = HLIST_HEAD_INIT, 60 .backing_objects = HLIST_HEAD_INIT,
60 .def = &fscache_fsdef_index_def, 61 .def = &fscache_fsdef_index_def,
diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h
index ee38fef4be51..12d505bedb5c 100644
--- a/fs/fscache/internal.h
+++ b/fs/fscache/internal.h
@@ -93,14 +93,11 @@ static inline bool fscache_object_congested(void)
93 93
94extern int fscache_wait_bit(void *); 94extern int fscache_wait_bit(void *);
95extern int fscache_wait_bit_interruptible(void *); 95extern int fscache_wait_bit_interruptible(void *);
96extern int fscache_wait_atomic_t(atomic_t *);
96 97
97/* 98/*
98 * object.c 99 * object.c
99 */ 100 */
100extern const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5];
101
102extern void fscache_withdrawing_object(struct fscache_cache *,
103 struct fscache_object *);
104extern void fscache_enqueue_object(struct fscache_object *); 101extern void fscache_enqueue_object(struct fscache_object *);
105 102
106/* 103/*
@@ -110,8 +107,10 @@ extern void fscache_enqueue_object(struct fscache_object *);
110extern const struct file_operations fscache_objlist_fops; 107extern const struct file_operations fscache_objlist_fops;
111 108
112extern void fscache_objlist_add(struct fscache_object *); 109extern void fscache_objlist_add(struct fscache_object *);
110extern void fscache_objlist_remove(struct fscache_object *);
113#else 111#else
114#define fscache_objlist_add(object) do {} while(0) 112#define fscache_objlist_add(object) do {} while(0)
113#define fscache_objlist_remove(object) do {} while(0)
115#endif 114#endif
116 115
117/* 116/*
@@ -291,6 +290,10 @@ static inline void fscache_raise_event(struct fscache_object *object,
291 unsigned event) 290 unsigned event)
292{ 291{
293 BUG_ON(event >= NR_FSCACHE_OBJECT_EVENTS); 292 BUG_ON(event >= NR_FSCACHE_OBJECT_EVENTS);
293#if 0
294 printk("*** fscache_raise_event(OBJ%d{%lx},%x)\n",
295 object->debug_id, object->event_mask, (1 << event));
296#endif
294 if (!test_and_set_bit(event, &object->events) && 297 if (!test_and_set_bit(event, &object->events) &&
295 test_bit(event, &object->event_mask)) 298 test_bit(event, &object->event_mask))
296 fscache_enqueue_object(object); 299 fscache_enqueue_object(object);
diff --git a/fs/fscache/main.c b/fs/fscache/main.c
index f9d856773f79..7c27907e650c 100644
--- a/fs/fscache/main.c
+++ b/fs/fscache/main.c
@@ -205,7 +205,6 @@ int fscache_wait_bit(void *flags)
205 schedule(); 205 schedule();
206 return 0; 206 return 0;
207} 207}
208EXPORT_SYMBOL(fscache_wait_bit);
209 208
210/* 209/*
211 * wait_on_bit() sleep function for interruptible waiting 210 * wait_on_bit() sleep function for interruptible waiting
@@ -215,4 +214,12 @@ int fscache_wait_bit_interruptible(void *flags)
215 schedule(); 214 schedule();
216 return signal_pending(current); 215 return signal_pending(current);
217} 216}
218EXPORT_SYMBOL(fscache_wait_bit_interruptible); 217
218/*
219 * wait_on_atomic_t() sleep function for uninterruptible waiting
220 */
221int fscache_wait_atomic_t(atomic_t *p)
222{
223 schedule();
224 return 0;
225}
diff --git a/fs/fscache/netfs.c b/fs/fscache/netfs.c
index e028b8eb1c40..b1bb6117473a 100644
--- a/fs/fscache/netfs.c
+++ b/fs/fscache/netfs.c
@@ -40,6 +40,7 @@ int __fscache_register_netfs(struct fscache_netfs *netfs)
40 /* initialise the primary index cookie */ 40 /* initialise the primary index cookie */
41 atomic_set(&netfs->primary_index->usage, 1); 41 atomic_set(&netfs->primary_index->usage, 1);
42 atomic_set(&netfs->primary_index->n_children, 0); 42 atomic_set(&netfs->primary_index->n_children, 0);
43 atomic_set(&netfs->primary_index->n_active, 1);
43 44
44 netfs->primary_index->def = &fscache_fsdef_netfs_def; 45 netfs->primary_index->def = &fscache_fsdef_netfs_def;
45 netfs->primary_index->parent = &fscache_fsdef_index; 46 netfs->primary_index->parent = &fscache_fsdef_index;
diff --git a/fs/fscache/object-list.c b/fs/fscache/object-list.c
index f27c89d17885..e1959efad64f 100644
--- a/fs/fscache/object-list.c
+++ b/fs/fscache/object-list.c
@@ -70,13 +70,10 @@ void fscache_objlist_add(struct fscache_object *obj)
70 write_unlock(&fscache_object_list_lock); 70 write_unlock(&fscache_object_list_lock);
71} 71}
72 72
73/** 73/*
74 * fscache_object_destroy - Note that a cache object is about to be destroyed 74 * Remove an object from the object list.
75 * @object: The object to be destroyed
76 *
77 * Note the imminent destruction and deallocation of a cache object record.
78 */ 75 */
79void fscache_object_destroy(struct fscache_object *obj) 76void fscache_objlist_remove(struct fscache_object *obj)
80{ 77{
81 write_lock(&fscache_object_list_lock); 78 write_lock(&fscache_object_list_lock);
82 79
@@ -85,7 +82,6 @@ void fscache_object_destroy(struct fscache_object *obj)
85 82
86 write_unlock(&fscache_object_list_lock); 83 write_unlock(&fscache_object_list_lock);
87} 84}
88EXPORT_SYMBOL(fscache_object_destroy);
89 85
90/* 86/*
91 * find the object in the tree on or after the specified index 87 * find the object in the tree on or after the specified index
@@ -166,15 +162,14 @@ static int fscache_objlist_show(struct seq_file *m, void *v)
166{ 162{
167 struct fscache_objlist_data *data = m->private; 163 struct fscache_objlist_data *data = m->private;
168 struct fscache_object *obj = v; 164 struct fscache_object *obj = v;
165 struct fscache_cookie *cookie;
169 unsigned long config = data->config; 166 unsigned long config = data->config;
170 uint16_t keylen, auxlen;
171 char _type[3], *type; 167 char _type[3], *type;
172 bool no_cookie;
173 u8 *buf = data->buf, *p; 168 u8 *buf = data->buf, *p;
174 169
175 if ((unsigned long) v == 1) { 170 if ((unsigned long) v == 1) {
176 seq_puts(m, "OBJECT PARENT STAT CHLDN OPS OOP IPR EX READS" 171 seq_puts(m, "OBJECT PARENT STAT CHLDN OPS OOP IPR EX READS"
177 " EM EV F S" 172 " EM EV FL S"
178 " | NETFS_COOKIE_DEF TY FL NETFS_DATA"); 173 " | NETFS_COOKIE_DEF TY FL NETFS_DATA");
179 if (config & (FSCACHE_OBJLIST_CONFIG_KEY | 174 if (config & (FSCACHE_OBJLIST_CONFIG_KEY |
180 FSCACHE_OBJLIST_CONFIG_AUX)) 175 FSCACHE_OBJLIST_CONFIG_AUX))
@@ -193,7 +188,7 @@ static int fscache_objlist_show(struct seq_file *m, void *v)
193 188
194 if ((unsigned long) v == 2) { 189 if ((unsigned long) v == 2) {
195 seq_puts(m, "======== ======== ==== ===== === === === == =====" 190 seq_puts(m, "======== ======== ==== ===== === === === == ====="
196 " == == = =" 191 " == == == ="
197 " | ================ == == ================"); 192 " | ================ == == ================");
198 if (config & (FSCACHE_OBJLIST_CONFIG_KEY | 193 if (config & (FSCACHE_OBJLIST_CONFIG_KEY |
199 FSCACHE_OBJLIST_CONFIG_AUX)) 194 FSCACHE_OBJLIST_CONFIG_AUX))
@@ -216,10 +211,11 @@ static int fscache_objlist_show(struct seq_file *m, void *v)
216 } \ 211 } \
217 } while(0) 212 } while(0)
218 213
214 cookie = obj->cookie;
219 if (~config) { 215 if (~config) {
220 FILTER(obj->cookie, 216 FILTER(cookie->def,
221 COOKIE, NOCOOKIE); 217 COOKIE, NOCOOKIE);
222 FILTER(obj->state != FSCACHE_OBJECT_ACTIVE || 218 FILTER(fscache_object_is_active(obj) ||
223 obj->n_ops != 0 || 219 obj->n_ops != 0 ||
224 obj->n_obj_ops != 0 || 220 obj->n_obj_ops != 0 ||
225 obj->flags || 221 obj->flags ||
@@ -235,10 +231,10 @@ static int fscache_objlist_show(struct seq_file *m, void *v)
235 } 231 }
236 232
237 seq_printf(m, 233 seq_printf(m,
238 "%8x %8x %s %5u %3u %3u %3u %2u %5u %2lx %2lx %1lx %1x | ", 234 "%8x %8x %s %5u %3u %3u %3u %2u %5u %2lx %2lx %2lx %1x | ",
239 obj->debug_id, 235 obj->debug_id,
240 obj->parent ? obj->parent->debug_id : -1, 236 obj->parent ? obj->parent->debug_id : -1,
241 fscache_object_states_short[obj->state], 237 obj->state->short_name,
242 obj->n_children, 238 obj->n_children,
243 obj->n_ops, 239 obj->n_ops,
244 obj->n_obj_ops, 240 obj->n_obj_ops,
@@ -250,48 +246,40 @@ static int fscache_objlist_show(struct seq_file *m, void *v)
250 obj->flags, 246 obj->flags,
251 work_busy(&obj->work)); 247 work_busy(&obj->work));
252 248
253 no_cookie = true; 249 if (fscache_use_cookie(obj)) {
254 keylen = auxlen = 0; 250 uint16_t keylen = 0, auxlen = 0;
255 if (obj->cookie) {
256 spin_lock(&obj->lock);
257 if (obj->cookie) {
258 switch (obj->cookie->def->type) {
259 case 0:
260 type = "IX";
261 break;
262 case 1:
263 type = "DT";
264 break;
265 default:
266 sprintf(_type, "%02u",
267 obj->cookie->def->type);
268 type = _type;
269 break;
270 }
271 251
272 seq_printf(m, "%-16s %s %2lx %16p", 252 switch (cookie->def->type) {
273 obj->cookie->def->name, 253 case 0:
274 type, 254 type = "IX";
275 obj->cookie->flags, 255 break;
276 obj->cookie->netfs_data); 256 case 1:
277 257 type = "DT";
278 if (obj->cookie->def->get_key && 258 break;
279 config & FSCACHE_OBJLIST_CONFIG_KEY) 259 default:
280 keylen = obj->cookie->def->get_key( 260 sprintf(_type, "%02u", cookie->def->type);
281 obj->cookie->netfs_data, 261 type = _type;
282 buf, 400); 262 break;
283
284 if (obj->cookie->def->get_aux &&
285 config & FSCACHE_OBJLIST_CONFIG_AUX)
286 auxlen = obj->cookie->def->get_aux(
287 obj->cookie->netfs_data,
288 buf + keylen, 512 - keylen);
289
290 no_cookie = false;
291 } 263 }
292 spin_unlock(&obj->lock);
293 264
294 if (!no_cookie && (keylen > 0 || auxlen > 0)) { 265 seq_printf(m, "%-16s %s %2lx %16p",
266 cookie->def->name,
267 type,
268 cookie->flags,
269 cookie->netfs_data);
270
271 if (cookie->def->get_key &&
272 config & FSCACHE_OBJLIST_CONFIG_KEY)
273 keylen = cookie->def->get_key(cookie->netfs_data,
274 buf, 400);
275
276 if (cookie->def->get_aux &&
277 config & FSCACHE_OBJLIST_CONFIG_AUX)
278 auxlen = cookie->def->get_aux(cookie->netfs_data,
279 buf + keylen, 512 - keylen);
280 fscache_unuse_cookie(obj);
281
282 if (keylen > 0 || auxlen > 0) {
295 seq_printf(m, " "); 283 seq_printf(m, " ");
296 for (p = buf; keylen > 0; keylen--) 284 for (p = buf; keylen > 0; keylen--)
297 seq_printf(m, "%02x", *p++); 285 seq_printf(m, "%02x", *p++);
@@ -302,12 +290,11 @@ static int fscache_objlist_show(struct seq_file *m, void *v)
302 seq_printf(m, "%02x", *p++); 290 seq_printf(m, "%02x", *p++);
303 } 291 }
304 } 292 }
305 }
306 293
307 if (no_cookie)
308 seq_printf(m, "<no_cookie>\n");
309 else
310 seq_printf(m, "\n"); 294 seq_printf(m, "\n");
295 } else {
296 seq_printf(m, "<no_netfs>\n");
297 }
311 return 0; 298 return 0;
312} 299}
313 300
diff --git a/fs/fscache/object.c b/fs/fscache/object.c
index 50d41c180211..86d75a60b20c 100644
--- a/fs/fscache/object.c
+++ b/fs/fscache/object.c
@@ -15,52 +15,131 @@
15#define FSCACHE_DEBUG_LEVEL COOKIE 15#define FSCACHE_DEBUG_LEVEL COOKIE
16#include <linux/module.h> 16#include <linux/module.h>
17#include <linux/slab.h> 17#include <linux/slab.h>
18#include <linux/prefetch.h>
18#include "internal.h" 19#include "internal.h"
19 20
20const char *fscache_object_states[FSCACHE_OBJECT__NSTATES] = { 21static const struct fscache_state *fscache_abort_initialisation(struct fscache_object *, int);
21 [FSCACHE_OBJECT_INIT] = "OBJECT_INIT", 22static const struct fscache_state *fscache_kill_dependents(struct fscache_object *, int);
22 [FSCACHE_OBJECT_LOOKING_UP] = "OBJECT_LOOKING_UP", 23static const struct fscache_state *fscache_drop_object(struct fscache_object *, int);
23 [FSCACHE_OBJECT_CREATING] = "OBJECT_CREATING", 24static const struct fscache_state *fscache_initialise_object(struct fscache_object *, int);
24 [FSCACHE_OBJECT_AVAILABLE] = "OBJECT_AVAILABLE", 25static const struct fscache_state *fscache_invalidate_object(struct fscache_object *, int);
25 [FSCACHE_OBJECT_ACTIVE] = "OBJECT_ACTIVE", 26static const struct fscache_state *fscache_jumpstart_dependents(struct fscache_object *, int);
26 [FSCACHE_OBJECT_INVALIDATING] = "OBJECT_INVALIDATING", 27static const struct fscache_state *fscache_kill_object(struct fscache_object *, int);
27 [FSCACHE_OBJECT_UPDATING] = "OBJECT_UPDATING", 28static const struct fscache_state *fscache_lookup_failure(struct fscache_object *, int);
28 [FSCACHE_OBJECT_DYING] = "OBJECT_DYING", 29static const struct fscache_state *fscache_look_up_object(struct fscache_object *, int);
29 [FSCACHE_OBJECT_LC_DYING] = "OBJECT_LC_DYING", 30static const struct fscache_state *fscache_object_available(struct fscache_object *, int);
30 [FSCACHE_OBJECT_ABORT_INIT] = "OBJECT_ABORT_INIT", 31static const struct fscache_state *fscache_parent_ready(struct fscache_object *, int);
31 [FSCACHE_OBJECT_RELEASING] = "OBJECT_RELEASING", 32static const struct fscache_state *fscache_update_object(struct fscache_object *, int);
32 [FSCACHE_OBJECT_RECYCLING] = "OBJECT_RECYCLING", 33
33 [FSCACHE_OBJECT_WITHDRAWING] = "OBJECT_WITHDRAWING", 34#define __STATE_NAME(n) fscache_osm_##n
34 [FSCACHE_OBJECT_DEAD] = "OBJECT_DEAD", 35#define STATE(n) (&__STATE_NAME(n))
36
37/*
38 * Define a work state. Work states are execution states. No event processing
39 * is performed by them. The function attached to a work state returns a
40 * pointer indicating the next state to which the state machine should
41 * transition. Returning NO_TRANSIT repeats the current state, but goes back
42 * to the scheduler first.
43 */
44#define WORK_STATE(n, sn, f) \
45 const struct fscache_state __STATE_NAME(n) = { \
46 .name = #n, \
47 .short_name = sn, \
48 .work = f \
49 }
50
51/*
52 * Returns from work states.
53 */
54#define transit_to(state) ({ prefetch(&STATE(state)->work); STATE(state); })
55
56#define NO_TRANSIT ((struct fscache_state *)NULL)
57
58/*
59 * Define a wait state. Wait states are event processing states. No execution
60 * is performed by them. Wait states are just tables of "if event X occurs,
61 * clear it and transition to state Y". The dispatcher returns to the
62 * scheduler if none of the events in which the wait state has an interest are
63 * currently pending.
64 */
65#define WAIT_STATE(n, sn, ...) \
66 const struct fscache_state __STATE_NAME(n) = { \
67 .name = #n, \
68 .short_name = sn, \
69 .work = NULL, \
70 .transitions = { __VA_ARGS__, { 0, NULL } } \
71 }
72
73#define TRANSIT_TO(state, emask) \
74 { .events = (emask), .transit_to = STATE(state) }
75
76/*
77 * The object state machine.
78 */
79static WORK_STATE(INIT_OBJECT, "INIT", fscache_initialise_object);
80static WORK_STATE(PARENT_READY, "PRDY", fscache_parent_ready);
81static WORK_STATE(ABORT_INIT, "ABRT", fscache_abort_initialisation);
82static WORK_STATE(LOOK_UP_OBJECT, "LOOK", fscache_look_up_object);
83static WORK_STATE(CREATE_OBJECT, "CRTO", fscache_look_up_object);
84static WORK_STATE(OBJECT_AVAILABLE, "AVBL", fscache_object_available);
85static WORK_STATE(JUMPSTART_DEPS, "JUMP", fscache_jumpstart_dependents);
86
87static WORK_STATE(INVALIDATE_OBJECT, "INVL", fscache_invalidate_object);
88static WORK_STATE(UPDATE_OBJECT, "UPDT", fscache_update_object);
89
90static WORK_STATE(LOOKUP_FAILURE, "LCFL", fscache_lookup_failure);
91static WORK_STATE(KILL_OBJECT, "KILL", fscache_kill_object);
92static WORK_STATE(KILL_DEPENDENTS, "KDEP", fscache_kill_dependents);
93static WORK_STATE(DROP_OBJECT, "DROP", fscache_drop_object);
94static WORK_STATE(OBJECT_DEAD, "DEAD", (void*)2UL);
95
96static WAIT_STATE(WAIT_FOR_INIT, "?INI",
97 TRANSIT_TO(INIT_OBJECT, 1 << FSCACHE_OBJECT_EV_NEW_CHILD));
98
99static WAIT_STATE(WAIT_FOR_PARENT, "?PRN",
100 TRANSIT_TO(PARENT_READY, 1 << FSCACHE_OBJECT_EV_PARENT_READY));
101
102static WAIT_STATE(WAIT_FOR_CMD, "?CMD",
103 TRANSIT_TO(INVALIDATE_OBJECT, 1 << FSCACHE_OBJECT_EV_INVALIDATE),
104 TRANSIT_TO(UPDATE_OBJECT, 1 << FSCACHE_OBJECT_EV_UPDATE),
105 TRANSIT_TO(JUMPSTART_DEPS, 1 << FSCACHE_OBJECT_EV_NEW_CHILD));
106
107static WAIT_STATE(WAIT_FOR_CLEARANCE, "?CLR",
108 TRANSIT_TO(KILL_OBJECT, 1 << FSCACHE_OBJECT_EV_CLEARED));
109
110/*
111 * Out-of-band event transition tables. These are for handling unexpected
112 * events, such as an I/O error. If an OOB event occurs, the state machine
113 * clears and disables the event and forces a transition to the nominated work
114 * state (acurrently executing work states will complete first).
115 *
116 * In such a situation, object->state remembers the state the machine should
117 * have been in/gone to and returning NO_TRANSIT returns to that.
118 */
119static const struct fscache_transition fscache_osm_init_oob[] = {
120 TRANSIT_TO(ABORT_INIT,
121 (1 << FSCACHE_OBJECT_EV_ERROR) |
122 (1 << FSCACHE_OBJECT_EV_KILL)),
123 { 0, NULL }
124};
125
126static const struct fscache_transition fscache_osm_lookup_oob[] = {
127 TRANSIT_TO(LOOKUP_FAILURE,
128 (1 << FSCACHE_OBJECT_EV_ERROR) |
129 (1 << FSCACHE_OBJECT_EV_KILL)),
130 { 0, NULL }
35}; 131};
36EXPORT_SYMBOL(fscache_object_states); 132
37 133static const struct fscache_transition fscache_osm_run_oob[] = {
38const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5] = { 134 TRANSIT_TO(KILL_OBJECT,
39 [FSCACHE_OBJECT_INIT] = "INIT", 135 (1 << FSCACHE_OBJECT_EV_ERROR) |
40 [FSCACHE_OBJECT_LOOKING_UP] = "LOOK", 136 (1 << FSCACHE_OBJECT_EV_KILL)),
41 [FSCACHE_OBJECT_CREATING] = "CRTN", 137 { 0, NULL }
42 [FSCACHE_OBJECT_AVAILABLE] = "AVBL",
43 [FSCACHE_OBJECT_ACTIVE] = "ACTV",
44 [FSCACHE_OBJECT_INVALIDATING] = "INVL",
45 [FSCACHE_OBJECT_UPDATING] = "UPDT",
46 [FSCACHE_OBJECT_DYING] = "DYNG",
47 [FSCACHE_OBJECT_LC_DYING] = "LCDY",
48 [FSCACHE_OBJECT_ABORT_INIT] = "ABTI",
49 [FSCACHE_OBJECT_RELEASING] = "RELS",
50 [FSCACHE_OBJECT_RECYCLING] = "RCYC",
51 [FSCACHE_OBJECT_WITHDRAWING] = "WTHD",
52 [FSCACHE_OBJECT_DEAD] = "DEAD",
53}; 138};
54 139
55static int fscache_get_object(struct fscache_object *); 140static int fscache_get_object(struct fscache_object *);
56static void fscache_put_object(struct fscache_object *); 141static void fscache_put_object(struct fscache_object *);
57static void fscache_initialise_object(struct fscache_object *); 142static bool fscache_enqueue_dependents(struct fscache_object *, int);
58static void fscache_lookup_object(struct fscache_object *);
59static void fscache_object_available(struct fscache_object *);
60static void fscache_invalidate_object(struct fscache_object *);
61static void fscache_release_object(struct fscache_object *);
62static void fscache_withdraw_object(struct fscache_object *);
63static void fscache_enqueue_dependents(struct fscache_object *);
64static void fscache_dequeue_object(struct fscache_object *); 143static void fscache_dequeue_object(struct fscache_object *);
65 144
66/* 145/*
@@ -75,295 +154,116 @@ static inline void fscache_done_parent_op(struct fscache_object *object)
75 object->debug_id, parent->debug_id, parent->n_ops); 154 object->debug_id, parent->debug_id, parent->n_ops);
76 155
77 spin_lock_nested(&parent->lock, 1); 156 spin_lock_nested(&parent->lock, 1);
78 parent->n_ops--;
79 parent->n_obj_ops--; 157 parent->n_obj_ops--;
158 parent->n_ops--;
80 if (parent->n_ops == 0) 159 if (parent->n_ops == 0)
81 fscache_raise_event(parent, FSCACHE_OBJECT_EV_CLEARED); 160 fscache_raise_event(parent, FSCACHE_OBJECT_EV_CLEARED);
82 spin_unlock(&parent->lock); 161 spin_unlock(&parent->lock);
83} 162}
84 163
85/* 164/*
86 * Notify netfs of invalidation completion. 165 * Object state machine dispatcher.
87 */ 166 */
88static inline void fscache_invalidation_complete(struct fscache_cookie *cookie) 167static void fscache_object_sm_dispatcher(struct fscache_object *object)
89{ 168{
90 if (test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) 169 const struct fscache_transition *t;
91 wake_up_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING); 170 const struct fscache_state *state, *new_state;
92} 171 unsigned long events, event_mask;
93 172 int event = -1;
94/*
95 * process events that have been sent to an object's state machine
96 * - initiates parent lookup
97 * - does object lookup
98 * - does object creation
99 * - does object recycling and retirement
100 * - does object withdrawal
101 */
102static void fscache_object_state_machine(struct fscache_object *object)
103{
104 enum fscache_object_state new_state;
105 struct fscache_cookie *cookie;
106 int event;
107 173
108 ASSERT(object != NULL); 174 ASSERT(object != NULL);
109 175
110 _enter("{OBJ%x,%s,%lx}", 176 _enter("{OBJ%x,%s,%lx}",
111 object->debug_id, fscache_object_states[object->state], 177 object->debug_id, object->state->name, object->events);
112 object->events); 178
113 179 event_mask = object->event_mask;
114 switch (object->state) { 180restart:
115 /* wait for the parent object to become ready */ 181 object->event_mask = 0; /* Mask normal event handling */
116 case FSCACHE_OBJECT_INIT: 182 state = object->state;
117 object->event_mask = 183restart_masked:
118 FSCACHE_OBJECT_EVENTS_MASK & 184 events = object->events;
119 ~(1 << FSCACHE_OBJECT_EV_CLEARED); 185
120 fscache_initialise_object(object); 186 /* Handle any out-of-band events (typically an error) */
121 goto done; 187 if (events & object->oob_event_mask) {
122 188 _debug("{OBJ%x} oob %lx",
123 /* look up the object metadata on disk */ 189 object->debug_id, events & object->oob_event_mask);
124 case FSCACHE_OBJECT_LOOKING_UP: 190 for (t = object->oob_table; t->events; t++) {
125 fscache_lookup_object(object); 191 if (events & t->events) {
126 goto lookup_transit; 192 state = t->transit_to;
127 193 ASSERT(state->work != NULL);
128 /* create the object metadata on disk */ 194 event = fls(events & t->events) - 1;
129 case FSCACHE_OBJECT_CREATING: 195 __clear_bit(event, &object->oob_event_mask);
130 fscache_lookup_object(object); 196 clear_bit(event, &object->events);
131 goto lookup_transit; 197 goto execute_work_state;
132 198 }
133 /* handle an object becoming available; start pending
134 * operations and queue dependent operations for processing */
135 case FSCACHE_OBJECT_AVAILABLE:
136 fscache_object_available(object);
137 goto active_transit;
138
139 /* normal running state */
140 case FSCACHE_OBJECT_ACTIVE:
141 goto active_transit;
142
143 /* Invalidate an object on disk */
144 case FSCACHE_OBJECT_INVALIDATING:
145 clear_bit(FSCACHE_OBJECT_EV_INVALIDATE, &object->events);
146 fscache_stat(&fscache_n_invalidates_run);
147 fscache_stat(&fscache_n_cop_invalidate_object);
148 fscache_invalidate_object(object);
149 fscache_stat_d(&fscache_n_cop_invalidate_object);
150 fscache_raise_event(object, FSCACHE_OBJECT_EV_UPDATE);
151 goto active_transit;
152
153 /* update the object metadata on disk */
154 case FSCACHE_OBJECT_UPDATING:
155 clear_bit(FSCACHE_OBJECT_EV_UPDATE, &object->events);
156 fscache_stat(&fscache_n_updates_run);
157 fscache_stat(&fscache_n_cop_update_object);
158 object->cache->ops->update_object(object);
159 fscache_stat_d(&fscache_n_cop_update_object);
160 goto active_transit;
161
162 /* handle an object dying during lookup or creation */
163 case FSCACHE_OBJECT_LC_DYING:
164 object->event_mask &= ~(1 << FSCACHE_OBJECT_EV_UPDATE);
165 fscache_stat(&fscache_n_cop_lookup_complete);
166 object->cache->ops->lookup_complete(object);
167 fscache_stat_d(&fscache_n_cop_lookup_complete);
168
169 spin_lock(&object->lock);
170 object->state = FSCACHE_OBJECT_DYING;
171 cookie = object->cookie;
172 if (cookie) {
173 if (test_and_clear_bit(FSCACHE_COOKIE_LOOKING_UP,
174 &cookie->flags))
175 wake_up_bit(&cookie->flags,
176 FSCACHE_COOKIE_LOOKING_UP);
177 if (test_and_clear_bit(FSCACHE_COOKIE_CREATING,
178 &cookie->flags))
179 wake_up_bit(&cookie->flags,
180 FSCACHE_COOKIE_CREATING);
181 } 199 }
182 spin_unlock(&object->lock); 200 }
183 201
184 fscache_done_parent_op(object); 202 /* Wait states are just transition tables */
203 if (!state->work) {
204 if (events & event_mask) {
205 for (t = state->transitions; t->events; t++) {
206 if (events & t->events) {
207 new_state = t->transit_to;
208 event = fls(events & t->events) - 1;
209 clear_bit(event, &object->events);
210 _debug("{OBJ%x} ev %d: %s -> %s",
211 object->debug_id, event,
212 state->name, new_state->name);
213 object->state = state = new_state;
214 goto execute_work_state;
215 }
216 }
185 217
186 /* wait for completion of all active operations on this object 218 /* The event mask didn't include all the tabled bits */
187 * and the death of all child objects of this object */ 219 BUG();
188 case FSCACHE_OBJECT_DYING:
189 dying:
190 clear_bit(FSCACHE_OBJECT_EV_CLEARED, &object->events);
191 spin_lock(&object->lock);
192 _debug("dying OBJ%x {%d,%d}",
193 object->debug_id, object->n_ops, object->n_children);
194 if (object->n_ops == 0 && object->n_children == 0) {
195 object->event_mask &=
196 ~(1 << FSCACHE_OBJECT_EV_CLEARED);
197 object->event_mask |=
198 (1 << FSCACHE_OBJECT_EV_WITHDRAW) |
199 (1 << FSCACHE_OBJECT_EV_RETIRE) |
200 (1 << FSCACHE_OBJECT_EV_RELEASE) |
201 (1 << FSCACHE_OBJECT_EV_ERROR);
202 } else {
203 object->event_mask &=
204 ~((1 << FSCACHE_OBJECT_EV_WITHDRAW) |
205 (1 << FSCACHE_OBJECT_EV_RETIRE) |
206 (1 << FSCACHE_OBJECT_EV_RELEASE) |
207 (1 << FSCACHE_OBJECT_EV_ERROR));
208 object->event_mask |=
209 1 << FSCACHE_OBJECT_EV_CLEARED;
210 } 220 }
211 spin_unlock(&object->lock); 221 /* Randomly woke up */
212 fscache_enqueue_dependents(object); 222 goto unmask_events;
213 fscache_start_operations(object);
214 goto terminal_transit;
215
216 /* handle an abort during initialisation */
217 case FSCACHE_OBJECT_ABORT_INIT:
218 _debug("handle abort init %lx", object->events);
219 object->event_mask &= ~(1 << FSCACHE_OBJECT_EV_UPDATE);
220
221 spin_lock(&object->lock);
222 fscache_dequeue_object(object);
223
224 object->state = FSCACHE_OBJECT_DYING;
225 if (test_and_clear_bit(FSCACHE_COOKIE_CREATING,
226 &object->cookie->flags))
227 wake_up_bit(&object->cookie->flags,
228 FSCACHE_COOKIE_CREATING);
229 spin_unlock(&object->lock);
230 goto dying;
231
232 /* handle the netfs releasing an object and possibly marking it
233 * obsolete too */
234 case FSCACHE_OBJECT_RELEASING:
235 case FSCACHE_OBJECT_RECYCLING:
236 object->event_mask &=
237 ~((1 << FSCACHE_OBJECT_EV_WITHDRAW) |
238 (1 << FSCACHE_OBJECT_EV_RETIRE) |
239 (1 << FSCACHE_OBJECT_EV_RELEASE) |
240 (1 << FSCACHE_OBJECT_EV_ERROR));
241 fscache_release_object(object);
242 spin_lock(&object->lock);
243 object->state = FSCACHE_OBJECT_DEAD;
244 spin_unlock(&object->lock);
245 fscache_stat(&fscache_n_object_dead);
246 goto terminal_transit;
247
248 /* handle the parent cache of this object being withdrawn from
249 * active service */
250 case FSCACHE_OBJECT_WITHDRAWING:
251 object->event_mask &=
252 ~((1 << FSCACHE_OBJECT_EV_WITHDRAW) |
253 (1 << FSCACHE_OBJECT_EV_RETIRE) |
254 (1 << FSCACHE_OBJECT_EV_RELEASE) |
255 (1 << FSCACHE_OBJECT_EV_ERROR));
256 fscache_withdraw_object(object);
257 spin_lock(&object->lock);
258 object->state = FSCACHE_OBJECT_DEAD;
259 spin_unlock(&object->lock);
260 fscache_stat(&fscache_n_object_dead);
261 goto terminal_transit;
262
263 /* complain about the object being woken up once it is
264 * deceased */
265 case FSCACHE_OBJECT_DEAD:
266 printk(KERN_ERR "FS-Cache:"
267 " Unexpected event in dead state %lx\n",
268 object->events & object->event_mask);
269 BUG();
270
271 default:
272 printk(KERN_ERR "FS-Cache: Unknown object state %u\n",
273 object->state);
274 BUG();
275 }
276
277 /* determine the transition from a lookup state */
278lookup_transit:
279 event = fls(object->events & object->event_mask) - 1;
280 switch (event) {
281 case FSCACHE_OBJECT_EV_WITHDRAW:
282 case FSCACHE_OBJECT_EV_RETIRE:
283 case FSCACHE_OBJECT_EV_RELEASE:
284 case FSCACHE_OBJECT_EV_ERROR:
285 new_state = FSCACHE_OBJECT_LC_DYING;
286 goto change_state;
287 case FSCACHE_OBJECT_EV_INVALIDATE:
288 new_state = FSCACHE_OBJECT_INVALIDATING;
289 goto change_state;
290 case FSCACHE_OBJECT_EV_REQUEUE:
291 goto done;
292 case -1:
293 goto done; /* sleep until event */
294 default:
295 goto unsupported_event;
296 } 223 }
297 224
298 /* determine the transition from an active state */ 225execute_work_state:
299active_transit: 226 _debug("{OBJ%x} exec %s", object->debug_id, state->name);
300 event = fls(object->events & object->event_mask) - 1;
301 switch (event) {
302 case FSCACHE_OBJECT_EV_WITHDRAW:
303 case FSCACHE_OBJECT_EV_RETIRE:
304 case FSCACHE_OBJECT_EV_RELEASE:
305 case FSCACHE_OBJECT_EV_ERROR:
306 new_state = FSCACHE_OBJECT_DYING;
307 goto change_state;
308 case FSCACHE_OBJECT_EV_INVALIDATE:
309 new_state = FSCACHE_OBJECT_INVALIDATING;
310 goto change_state;
311 case FSCACHE_OBJECT_EV_UPDATE:
312 new_state = FSCACHE_OBJECT_UPDATING;
313 goto change_state;
314 case -1:
315 new_state = FSCACHE_OBJECT_ACTIVE;
316 goto change_state; /* sleep until event */
317 default:
318 goto unsupported_event;
319 }
320 227
321 /* determine the transition from a terminal state */ 228 new_state = state->work(object, event);
322terminal_transit: 229 event = -1;
323 event = fls(object->events & object->event_mask) - 1; 230 if (new_state == NO_TRANSIT) {
324 switch (event) { 231 _debug("{OBJ%x} %s notrans", object->debug_id, state->name);
325 case FSCACHE_OBJECT_EV_WITHDRAW: 232 fscache_enqueue_object(object);
326 new_state = FSCACHE_OBJECT_WITHDRAWING; 233 event_mask = object->oob_event_mask;
327 goto change_state; 234 goto unmask_events;
328 case FSCACHE_OBJECT_EV_RETIRE:
329 new_state = FSCACHE_OBJECT_RECYCLING;
330 goto change_state;
331 case FSCACHE_OBJECT_EV_RELEASE:
332 new_state = FSCACHE_OBJECT_RELEASING;
333 goto change_state;
334 case FSCACHE_OBJECT_EV_ERROR:
335 new_state = FSCACHE_OBJECT_WITHDRAWING;
336 goto change_state;
337 case FSCACHE_OBJECT_EV_CLEARED:
338 new_state = FSCACHE_OBJECT_DYING;
339 goto change_state;
340 case -1:
341 goto done; /* sleep until event */
342 default:
343 goto unsupported_event;
344 } 235 }
345 236
346change_state: 237 _debug("{OBJ%x} %s -> %s",
347 spin_lock(&object->lock); 238 object->debug_id, state->name, new_state->name);
348 object->state = new_state; 239 object->state = state = new_state;
349 spin_unlock(&object->lock);
350 240
351done: 241 if (state->work) {
352 _leave(" [->%s]", fscache_object_states[object->state]); 242 if (unlikely(state->work == ((void *)2UL))) {
353 return; 243 _leave(" [dead]");
244 return;
245 }
246 goto restart_masked;
247 }
354 248
355unsupported_event: 249 /* Transited to wait state */
356 printk(KERN_ERR "FS-Cache:" 250 event_mask = object->oob_event_mask;
357 " Unsupported event %d [%lx/%lx] in state %s\n", 251 for (t = state->transitions; t->events; t++)
358 event, object->events, object->event_mask, 252 event_mask |= t->events;
359 fscache_object_states[object->state]); 253
360 BUG(); 254unmask_events:
255 object->event_mask = event_mask;
256 smp_mb();
257 events = object->events;
258 if (events & event_mask)
259 goto restart;
260 _leave(" [msk %lx]", event_mask);
361} 261}
362 262
363/* 263/*
364 * execute an object 264 * execute an object
365 */ 265 */
366void fscache_object_work_func(struct work_struct *work) 266static void fscache_object_work_func(struct work_struct *work)
367{ 267{
368 struct fscache_object *object = 268 struct fscache_object *object =
369 container_of(work, struct fscache_object, work); 269 container_of(work, struct fscache_object, work);
@@ -372,14 +272,70 @@ void fscache_object_work_func(struct work_struct *work)
372 _enter("{OBJ%x}", object->debug_id); 272 _enter("{OBJ%x}", object->debug_id);
373 273
374 start = jiffies; 274 start = jiffies;
375 fscache_object_state_machine(object); 275 fscache_object_sm_dispatcher(object);
376 fscache_hist(fscache_objs_histogram, start); 276 fscache_hist(fscache_objs_histogram, start);
377 if (object->events & object->event_mask)
378 fscache_enqueue_object(object);
379 clear_bit(FSCACHE_OBJECT_EV_REQUEUE, &object->events);
380 fscache_put_object(object); 277 fscache_put_object(object);
381} 278}
382EXPORT_SYMBOL(fscache_object_work_func); 279
280/**
281 * fscache_object_init - Initialise a cache object description
282 * @object: Object description
283 * @cookie: Cookie object will be attached to
284 * @cache: Cache in which backing object will be found
285 *
286 * Initialise a cache object description to its basic values.
287 *
288 * See Documentation/filesystems/caching/backend-api.txt for a complete
289 * description.
290 */
291void fscache_object_init(struct fscache_object *object,
292 struct fscache_cookie *cookie,
293 struct fscache_cache *cache)
294{
295 const struct fscache_transition *t;
296
297 atomic_inc(&cache->object_count);
298
299 object->state = STATE(WAIT_FOR_INIT);
300 object->oob_table = fscache_osm_init_oob;
301 object->flags = 1 << FSCACHE_OBJECT_IS_LIVE;
302 spin_lock_init(&object->lock);
303 INIT_LIST_HEAD(&object->cache_link);
304 INIT_HLIST_NODE(&object->cookie_link);
305 INIT_WORK(&object->work, fscache_object_work_func);
306 INIT_LIST_HEAD(&object->dependents);
307 INIT_LIST_HEAD(&object->dep_link);
308 INIT_LIST_HEAD(&object->pending_ops);
309 object->n_children = 0;
310 object->n_ops = object->n_in_progress = object->n_exclusive = 0;
311 object->events = 0;
312 object->store_limit = 0;
313 object->store_limit_l = 0;
314 object->cache = cache;
315 object->cookie = cookie;
316 object->parent = NULL;
317
318 object->oob_event_mask = 0;
319 for (t = object->oob_table; t->events; t++)
320 object->oob_event_mask |= t->events;
321 object->event_mask = object->oob_event_mask;
322 for (t = object->state->transitions; t->events; t++)
323 object->event_mask |= t->events;
324}
325EXPORT_SYMBOL(fscache_object_init);
326
327/*
328 * Abort object initialisation before we start it.
329 */
330static const struct fscache_state *fscache_abort_initialisation(struct fscache_object *object,
331 int event)
332{
333 _enter("{OBJ%x},%d", object->debug_id, event);
334
335 object->oob_event_mask = 0;
336 fscache_dequeue_object(object);
337 return transit_to(KILL_OBJECT);
338}
383 339
384/* 340/*
385 * initialise an object 341 * initialise an object
@@ -387,130 +343,136 @@ EXPORT_SYMBOL(fscache_object_work_func);
387 * immediately to do a creation 343 * immediately to do a creation
388 * - we may need to start the process of creating a parent and we need to wait 344 * - we may need to start the process of creating a parent and we need to wait
389 * for the parent's lookup and creation to complete if it's not there yet 345 * for the parent's lookup and creation to complete if it's not there yet
390 * - an object's cookie is pinned until we clear FSCACHE_COOKIE_CREATING on the
391 * leaf-most cookies of the object and all its children
392 */ 346 */
393static void fscache_initialise_object(struct fscache_object *object) 347static const struct fscache_state *fscache_initialise_object(struct fscache_object *object,
348 int event)
394{ 349{
395 struct fscache_object *parent; 350 struct fscache_object *parent;
351 bool success;
396 352
397 _enter(""); 353 _enter("{OBJ%x},%d", object->debug_id, event);
398 ASSERT(object->cookie != NULL);
399 ASSERT(object->cookie->parent != NULL);
400
401 if (object->events & ((1 << FSCACHE_OBJECT_EV_ERROR) |
402 (1 << FSCACHE_OBJECT_EV_RELEASE) |
403 (1 << FSCACHE_OBJECT_EV_RETIRE) |
404 (1 << FSCACHE_OBJECT_EV_WITHDRAW))) {
405 _debug("abort init %lx", object->events);
406 spin_lock(&object->lock);
407 object->state = FSCACHE_OBJECT_ABORT_INIT;
408 spin_unlock(&object->lock);
409 return;
410 }
411 354
412 spin_lock(&object->cookie->lock); 355 ASSERT(list_empty(&object->dep_link));
413 spin_lock_nested(&object->cookie->parent->lock, 1);
414 356
415 parent = object->parent; 357 parent = object->parent;
416 if (!parent) { 358 if (!parent) {
417 _debug("no parent"); 359 _leave(" [no parent]");
418 set_bit(FSCACHE_OBJECT_EV_WITHDRAW, &object->events); 360 return transit_to(DROP_OBJECT);
419 } else { 361 }
420 spin_lock(&object->lock);
421 spin_lock_nested(&parent->lock, 1);
422 _debug("parent %s", fscache_object_states[parent->state]);
423
424 if (parent->state >= FSCACHE_OBJECT_DYING) {
425 _debug("bad parent");
426 set_bit(FSCACHE_OBJECT_EV_WITHDRAW, &object->events);
427 } else if (parent->state < FSCACHE_OBJECT_AVAILABLE) {
428 _debug("wait");
429
430 /* we may get woken up in this state by child objects
431 * binding on to us, so we need to make sure we don't
432 * add ourself to the list multiple times */
433 if (list_empty(&object->dep_link)) {
434 fscache_stat(&fscache_n_cop_grab_object);
435 object->cache->ops->grab_object(object);
436 fscache_stat_d(&fscache_n_cop_grab_object);
437 list_add(&object->dep_link,
438 &parent->dependents);
439
440 /* fscache_acquire_non_index_cookie() uses this
441 * to wake the chain up */
442 if (parent->state == FSCACHE_OBJECT_INIT)
443 fscache_enqueue_object(parent);
444 }
445 } else {
446 _debug("go");
447 parent->n_ops++;
448 parent->n_obj_ops++;
449 object->lookup_jif = jiffies;
450 object->state = FSCACHE_OBJECT_LOOKING_UP;
451 set_bit(FSCACHE_OBJECT_EV_REQUEUE, &object->events);
452 }
453 362
454 spin_unlock(&parent->lock); 363 _debug("parent: %s of:%lx", parent->state->name, parent->flags);
455 spin_unlock(&object->lock); 364
365 if (fscache_object_is_dying(parent)) {
366 _leave(" [bad parent]");
367 return transit_to(DROP_OBJECT);
456 } 368 }
457 369
458 spin_unlock(&object->cookie->parent->lock); 370 if (fscache_object_is_available(parent)) {
459 spin_unlock(&object->cookie->lock); 371 _leave(" [ready]");
372 return transit_to(PARENT_READY);
373 }
374
375 _debug("wait");
376
377 spin_lock(&parent->lock);
378 fscache_stat(&fscache_n_cop_grab_object);
379 success = false;
380 if (fscache_object_is_live(parent) &&
381 object->cache->ops->grab_object(object)) {
382 list_add(&object->dep_link, &parent->dependents);
383 success = true;
384 }
385 fscache_stat_d(&fscache_n_cop_grab_object);
386 spin_unlock(&parent->lock);
387 if (!success) {
388 _leave(" [grab failed]");
389 return transit_to(DROP_OBJECT);
390 }
391
392 /* fscache_acquire_non_index_cookie() uses this
393 * to wake the chain up */
394 fscache_raise_event(parent, FSCACHE_OBJECT_EV_NEW_CHILD);
395 _leave(" [wait]");
396 return transit_to(WAIT_FOR_PARENT);
397}
398
399/*
400 * Once the parent object is ready, we should kick off our lookup op.
401 */
402static const struct fscache_state *fscache_parent_ready(struct fscache_object *object,
403 int event)
404{
405 struct fscache_object *parent = object->parent;
406
407 _enter("{OBJ%x},%d", object->debug_id, event);
408
409 ASSERT(parent != NULL);
410
411 spin_lock(&parent->lock);
412 parent->n_ops++;
413 parent->n_obj_ops++;
414 object->lookup_jif = jiffies;
415 spin_unlock(&parent->lock);
416
460 _leave(""); 417 _leave("");
418 return transit_to(LOOK_UP_OBJECT);
461} 419}
462 420
463/* 421/*
464 * look an object up in the cache from which it was allocated 422 * look an object up in the cache from which it was allocated
465 * - we hold an "access lock" on the parent object, so the parent object cannot 423 * - we hold an "access lock" on the parent object, so the parent object cannot
466 * be withdrawn by either party till we've finished 424 * be withdrawn by either party till we've finished
467 * - an object's cookie is pinned until we clear FSCACHE_COOKIE_CREATING on the
468 * leaf-most cookies of the object and all its children
469 */ 425 */
470static void fscache_lookup_object(struct fscache_object *object) 426static const struct fscache_state *fscache_look_up_object(struct fscache_object *object,
427 int event)
471{ 428{
472 struct fscache_cookie *cookie = object->cookie; 429 struct fscache_cookie *cookie = object->cookie;
473 struct fscache_object *parent; 430 struct fscache_object *parent = object->parent;
474 int ret; 431 int ret;
475 432
476 _enter(""); 433 _enter("{OBJ%x},%d", object->debug_id, event);
434
435 object->oob_table = fscache_osm_lookup_oob;
477 436
478 parent = object->parent;
479 ASSERT(parent != NULL); 437 ASSERT(parent != NULL);
480 ASSERTCMP(parent->n_ops, >, 0); 438 ASSERTCMP(parent->n_ops, >, 0);
481 ASSERTCMP(parent->n_obj_ops, >, 0); 439 ASSERTCMP(parent->n_obj_ops, >, 0);
482 440
483 /* make sure the parent is still available */ 441 /* make sure the parent is still available */
484 ASSERTCMP(parent->state, >=, FSCACHE_OBJECT_AVAILABLE); 442 ASSERT(fscache_object_is_available(parent));
485 443
486 if (parent->state >= FSCACHE_OBJECT_DYING || 444 if (fscache_object_is_dying(parent) ||
487 test_bit(FSCACHE_IOERROR, &object->cache->flags)) { 445 test_bit(FSCACHE_IOERROR, &object->cache->flags) ||
488 _debug("unavailable"); 446 !fscache_use_cookie(object)) {
489 set_bit(FSCACHE_OBJECT_EV_WITHDRAW, &object->events); 447 _leave(" [unavailable]");
490 _leave(""); 448 return transit_to(LOOKUP_FAILURE);
491 return;
492 } 449 }
493 450
494 _debug("LOOKUP \"%s/%s\" in \"%s\"", 451 _debug("LOOKUP \"%s\" in \"%s\"",
495 parent->cookie->def->name, cookie->def->name, 452 cookie->def->name, object->cache->tag->name);
496 object->cache->tag->name);
497 453
498 fscache_stat(&fscache_n_object_lookups); 454 fscache_stat(&fscache_n_object_lookups);
499 fscache_stat(&fscache_n_cop_lookup_object); 455 fscache_stat(&fscache_n_cop_lookup_object);
500 ret = object->cache->ops->lookup_object(object); 456 ret = object->cache->ops->lookup_object(object);
501 fscache_stat_d(&fscache_n_cop_lookup_object); 457 fscache_stat_d(&fscache_n_cop_lookup_object);
502 458
503 if (test_bit(FSCACHE_OBJECT_EV_ERROR, &object->events)) 459 fscache_unuse_cookie(object);
504 set_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
505 460
506 if (ret == -ETIMEDOUT) { 461 if (ret == -ETIMEDOUT) {
507 /* probably stuck behind another object, so move this one to 462 /* probably stuck behind another object, so move this one to
508 * the back of the queue */ 463 * the back of the queue */
509 fscache_stat(&fscache_n_object_lookups_timed_out); 464 fscache_stat(&fscache_n_object_lookups_timed_out);
510 set_bit(FSCACHE_OBJECT_EV_REQUEUE, &object->events); 465 _leave(" [timeout]");
466 return NO_TRANSIT;
511 } 467 }
512 468
513 _leave(""); 469 if (ret < 0) {
470 _leave(" [error]");
471 return transit_to(LOOKUP_FAILURE);
472 }
473
474 _leave(" [ok]");
475 return transit_to(OBJECT_AVAILABLE);
514} 476}
515 477
516/** 478/**
@@ -524,32 +486,20 @@ void fscache_object_lookup_negative(struct fscache_object *object)
524{ 486{
525 struct fscache_cookie *cookie = object->cookie; 487 struct fscache_cookie *cookie = object->cookie;
526 488
527 _enter("{OBJ%x,%s}", 489 _enter("{OBJ%x,%s}", object->debug_id, object->state->name);
528 object->debug_id, fscache_object_states[object->state]);
529 490
530 spin_lock(&object->lock); 491 if (!test_and_set_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags)) {
531 if (object->state == FSCACHE_OBJECT_LOOKING_UP) {
532 fscache_stat(&fscache_n_object_lookups_negative); 492 fscache_stat(&fscache_n_object_lookups_negative);
533 493
534 /* transit here to allow write requests to begin stacking up 494 /* Allow write requests to begin stacking up and read requests to begin
535 * and read requests to begin returning ENODATA */ 495 * returning ENODATA.
536 object->state = FSCACHE_OBJECT_CREATING; 496 */
537 spin_unlock(&object->lock);
538
539 set_bit(FSCACHE_COOKIE_PENDING_FILL, &cookie->flags);
540 set_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags); 497 set_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
541 498
542 _debug("wake up lookup %p", &cookie->flags); 499 _debug("wake up lookup %p", &cookie->flags);
543 smp_mb__before_clear_bit(); 500 clear_bit_unlock(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
544 clear_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
545 smp_mb__after_clear_bit();
546 wake_up_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP); 501 wake_up_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP);
547 set_bit(FSCACHE_OBJECT_EV_REQUEUE, &object->events);
548 } else {
549 ASSERTCMP(object->state, ==, FSCACHE_OBJECT_CREATING);
550 spin_unlock(&object->lock);
551 } 502 }
552
553 _leave(""); 503 _leave("");
554} 504}
555EXPORT_SYMBOL(fscache_object_lookup_negative); 505EXPORT_SYMBOL(fscache_object_lookup_negative);
@@ -568,38 +518,26 @@ void fscache_obtained_object(struct fscache_object *object)
568{ 518{
569 struct fscache_cookie *cookie = object->cookie; 519 struct fscache_cookie *cookie = object->cookie;
570 520
571 _enter("{OBJ%x,%s}", 521 _enter("{OBJ%x,%s}", object->debug_id, object->state->name);
572 object->debug_id, fscache_object_states[object->state]);
573 522
574 /* if we were still looking up, then we must have a positive lookup 523 /* if we were still looking up, then we must have a positive lookup
575 * result, in which case there may be data available */ 524 * result, in which case there may be data available */
576 spin_lock(&object->lock); 525 if (!test_and_set_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags)) {
577 if (object->state == FSCACHE_OBJECT_LOOKING_UP) {
578 fscache_stat(&fscache_n_object_lookups_positive); 526 fscache_stat(&fscache_n_object_lookups_positive);
579 527
580 clear_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags); 528 /* We do (presumably) have data */
529 clear_bit_unlock(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
581 530
582 object->state = FSCACHE_OBJECT_AVAILABLE; 531 /* Allow write requests to begin stacking up and read requests
583 spin_unlock(&object->lock); 532 * to begin shovelling data.
584 533 */
585 smp_mb__before_clear_bit(); 534 clear_bit_unlock(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
586 clear_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
587 smp_mb__after_clear_bit();
588 wake_up_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP); 535 wake_up_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP);
589 set_bit(FSCACHE_OBJECT_EV_REQUEUE, &object->events);
590 } else { 536 } else {
591 ASSERTCMP(object->state, ==, FSCACHE_OBJECT_CREATING);
592 fscache_stat(&fscache_n_object_created); 537 fscache_stat(&fscache_n_object_created);
593
594 object->state = FSCACHE_OBJECT_AVAILABLE;
595 spin_unlock(&object->lock);
596 set_bit(FSCACHE_OBJECT_EV_REQUEUE, &object->events);
597 smp_wmb();
598 } 538 }
599 539
600 if (test_and_clear_bit(FSCACHE_COOKIE_CREATING, &cookie->flags)) 540 set_bit(FSCACHE_OBJECT_IS_AVAILABLE, &object->flags);
601 wake_up_bit(&cookie->flags, FSCACHE_COOKIE_CREATING);
602
603 _leave(""); 541 _leave("");
604} 542}
605EXPORT_SYMBOL(fscache_obtained_object); 543EXPORT_SYMBOL(fscache_obtained_object);
@@ -607,15 +545,14 @@ EXPORT_SYMBOL(fscache_obtained_object);
607/* 545/*
608 * handle an object that has just become available 546 * handle an object that has just become available
609 */ 547 */
610static void fscache_object_available(struct fscache_object *object) 548static const struct fscache_state *fscache_object_available(struct fscache_object *object,
549 int event)
611{ 550{
612 _enter("{OBJ%x}", object->debug_id); 551 _enter("{OBJ%x},%d", object->debug_id, event);
613 552
614 spin_lock(&object->lock); 553 object->oob_table = fscache_osm_run_oob;
615 554
616 if (object->cookie && 555 spin_lock(&object->lock);
617 test_and_clear_bit(FSCACHE_COOKIE_CREATING, &object->cookie->flags))
618 wake_up_bit(&object->cookie->flags, FSCACHE_COOKIE_CREATING);
619 556
620 fscache_done_parent_op(object); 557 fscache_done_parent_op(object);
621 if (object->n_in_progress == 0) { 558 if (object->n_in_progress == 0) {
@@ -631,130 +568,158 @@ static void fscache_object_available(struct fscache_object *object)
631 fscache_stat(&fscache_n_cop_lookup_complete); 568 fscache_stat(&fscache_n_cop_lookup_complete);
632 object->cache->ops->lookup_complete(object); 569 object->cache->ops->lookup_complete(object);
633 fscache_stat_d(&fscache_n_cop_lookup_complete); 570 fscache_stat_d(&fscache_n_cop_lookup_complete);
634 fscache_enqueue_dependents(object);
635 571
636 fscache_hist(fscache_obj_instantiate_histogram, object->lookup_jif); 572 fscache_hist(fscache_obj_instantiate_histogram, object->lookup_jif);
637 fscache_stat(&fscache_n_object_avail); 573 fscache_stat(&fscache_n_object_avail);
638 574
639 _leave(""); 575 _leave("");
576 return transit_to(JUMPSTART_DEPS);
640} 577}
641 578
642/* 579/*
643 * drop an object's attachments 580 * Wake up this object's dependent objects now that we've become available.
644 */ 581 */
645static void fscache_drop_object(struct fscache_object *object) 582static const struct fscache_state *fscache_jumpstart_dependents(struct fscache_object *object,
583 int event)
646{ 584{
647 struct fscache_object *parent = object->parent; 585 _enter("{OBJ%x},%d", object->debug_id, event);
648 struct fscache_cache *cache = object->cache;
649 586
650 _enter("{OBJ%x,%d}", object->debug_id, object->n_children); 587 if (!fscache_enqueue_dependents(object, FSCACHE_OBJECT_EV_PARENT_READY))
588 return NO_TRANSIT; /* Not finished; requeue */
589 return transit_to(WAIT_FOR_CMD);
590}
651 591
652 ASSERTCMP(object->cookie, ==, NULL); 592/*
653 ASSERT(hlist_unhashed(&object->cookie_link)); 593 * Handle lookup or creation failute.
594 */
595static const struct fscache_state *fscache_lookup_failure(struct fscache_object *object,
596 int event)
597{
598 struct fscache_cookie *cookie;
654 599
655 spin_lock(&cache->object_list_lock); 600 _enter("{OBJ%x},%d", object->debug_id, event);
656 list_del_init(&object->cache_link);
657 spin_unlock(&cache->object_list_lock);
658 601
659 fscache_stat(&fscache_n_cop_drop_object); 602 object->oob_event_mask = 0;
660 cache->ops->drop_object(object);
661 fscache_stat_d(&fscache_n_cop_drop_object);
662 603
663 if (parent) { 604 fscache_stat(&fscache_n_cop_lookup_complete);
664 _debug("release parent OBJ%x {%d}", 605 object->cache->ops->lookup_complete(object);
665 parent->debug_id, parent->n_children); 606 fscache_stat_d(&fscache_n_cop_lookup_complete);
666 607
667 spin_lock(&parent->lock); 608 cookie = object->cookie;
668 parent->n_children--; 609 set_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
669 if (parent->n_children == 0) 610 if (test_and_clear_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags))
670 fscache_raise_event(parent, FSCACHE_OBJECT_EV_CLEARED); 611 wake_up_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP);
671 spin_unlock(&parent->lock); 612
672 object->parent = NULL; 613 fscache_done_parent_op(object);
614 return transit_to(KILL_OBJECT);
615}
616
617/*
618 * Wait for completion of all active operations on this object and the death of
619 * all child objects of this object.
620 */
621static const struct fscache_state *fscache_kill_object(struct fscache_object *object,
622 int event)
623{
624 _enter("{OBJ%x,%d,%d},%d",
625 object->debug_id, object->n_ops, object->n_children, event);
626
627 clear_bit(FSCACHE_OBJECT_IS_LIVE, &object->flags);
628 object->oob_event_mask = 0;
629
630 if (list_empty(&object->dependents) &&
631 object->n_ops == 0 &&
632 object->n_children == 0)
633 return transit_to(DROP_OBJECT);
634
635 if (object->n_in_progress == 0) {
636 spin_lock(&object->lock);
637 if (object->n_ops > 0 && object->n_in_progress == 0)
638 fscache_start_operations(object);
639 spin_unlock(&object->lock);
673 } 640 }
674 641
675 /* this just shifts the object release to the work processor */ 642 if (!list_empty(&object->dependents))
676 fscache_put_object(object); 643 return transit_to(KILL_DEPENDENTS);
677 644
678 _leave(""); 645 return transit_to(WAIT_FOR_CLEARANCE);
679} 646}
680 647
681/* 648/*
682 * release or recycle an object that the netfs has discarded 649 * Kill dependent objects.
683 */ 650 */
684static void fscache_release_object(struct fscache_object *object) 651static const struct fscache_state *fscache_kill_dependents(struct fscache_object *object,
652 int event)
685{ 653{
686 _enter(""); 654 _enter("{OBJ%x},%d", object->debug_id, event);
687 655
688 fscache_drop_object(object); 656 if (!fscache_enqueue_dependents(object, FSCACHE_OBJECT_EV_KILL))
657 return NO_TRANSIT; /* Not finished */
658 return transit_to(WAIT_FOR_CLEARANCE);
689} 659}
690 660
691/* 661/*
692 * withdraw an object from active service 662 * Drop an object's attachments
693 */ 663 */
694static void fscache_withdraw_object(struct fscache_object *object) 664static const struct fscache_state *fscache_drop_object(struct fscache_object *object,
665 int event)
695{ 666{
696 struct fscache_cookie *cookie; 667 struct fscache_object *parent = object->parent;
697 bool detached; 668 struct fscache_cookie *cookie = object->cookie;
669 struct fscache_cache *cache = object->cache;
670 bool awaken = false;
698 671
699 _enter(""); 672 _enter("{OBJ%x,%d},%d", object->debug_id, object->n_children, event);
700 673
701 spin_lock(&object->lock); 674 ASSERT(cookie != NULL);
702 cookie = object->cookie; 675 ASSERT(!hlist_unhashed(&object->cookie_link));
703 if (cookie) {
704 /* need to get the cookie lock before the object lock, starting
705 * from the object pointer */
706 atomic_inc(&cookie->usage);
707 spin_unlock(&object->lock);
708 676
709 detached = false; 677 /* Make sure the cookie no longer points here and that the netfs isn't
710 spin_lock(&cookie->lock); 678 * waiting for us.
711 spin_lock(&object->lock); 679 */
680 spin_lock(&cookie->lock);
681 hlist_del_init(&object->cookie_link);
682 if (test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
683 awaken = true;
684 spin_unlock(&cookie->lock);
712 685
713 if (object->cookie == cookie) { 686 if (awaken)
714 hlist_del_init(&object->cookie_link); 687 wake_up_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING);
715 object->cookie = NULL;
716 fscache_invalidation_complete(cookie);
717 detached = true;
718 }
719 spin_unlock(&cookie->lock);
720 fscache_cookie_put(cookie);
721 if (detached)
722 fscache_cookie_put(cookie);
723 }
724 688
689 /* Prevent a race with our last child, which has to signal EV_CLEARED
690 * before dropping our spinlock.
691 */
692 spin_lock(&object->lock);
725 spin_unlock(&object->lock); 693 spin_unlock(&object->lock);
726 694
727 fscache_drop_object(object); 695 /* Discard from the cache's collection of objects */
728} 696 spin_lock(&cache->object_list_lock);
697 list_del_init(&object->cache_link);
698 spin_unlock(&cache->object_list_lock);
729 699
730/* 700 fscache_stat(&fscache_n_cop_drop_object);
731 * withdraw an object from active service at the behest of the cache 701 cache->ops->drop_object(object);
732 * - need break the links to a cached object cookie 702 fscache_stat_d(&fscache_n_cop_drop_object);
733 * - called under two situations:
734 * (1) recycler decides to reclaim an in-use object
735 * (2) a cache is unmounted
736 * - have to take care as the cookie can be being relinquished by the netfs
737 * simultaneously
738 * - the object is pinned by the caller holding a refcount on it
739 */
740void fscache_withdrawing_object(struct fscache_cache *cache,
741 struct fscache_object *object)
742{
743 bool enqueue = false;
744 703
745 _enter(",OBJ%x", object->debug_id); 704 /* The parent object wants to know when all it dependents have gone */
705 if (parent) {
706 _debug("release parent OBJ%x {%d}",
707 parent->debug_id, parent->n_children);
746 708
747 spin_lock(&object->lock); 709 spin_lock(&parent->lock);
748 if (object->state < FSCACHE_OBJECT_WITHDRAWING) { 710 parent->n_children--;
749 object->state = FSCACHE_OBJECT_WITHDRAWING; 711 if (parent->n_children == 0)
750 enqueue = true; 712 fscache_raise_event(parent, FSCACHE_OBJECT_EV_CLEARED);
713 spin_unlock(&parent->lock);
714 object->parent = NULL;
751 } 715 }
752 spin_unlock(&object->lock);
753 716
754 if (enqueue) 717 /* this just shifts the object release to the work processor */
755 fscache_enqueue_object(object); 718 fscache_put_object(object);
719 fscache_stat(&fscache_n_object_dead);
756 720
757 _leave(""); 721 _leave("");
722 return transit_to(OBJECT_DEAD);
758} 723}
759 724
760/* 725/*
@@ -771,7 +736,7 @@ static int fscache_get_object(struct fscache_object *object)
771} 736}
772 737
773/* 738/*
774 * discard a ref on a work item 739 * Discard a ref on an object
775 */ 740 */
776static void fscache_put_object(struct fscache_object *object) 741static void fscache_put_object(struct fscache_object *object)
777{ 742{
@@ -780,6 +745,22 @@ static void fscache_put_object(struct fscache_object *object)
780 fscache_stat_d(&fscache_n_cop_put_object); 745 fscache_stat_d(&fscache_n_cop_put_object);
781} 746}
782 747
748/**
749 * fscache_object_destroy - Note that a cache object is about to be destroyed
750 * @object: The object to be destroyed
751 *
752 * Note the imminent destruction and deallocation of a cache object record.
753 */
754void fscache_object_destroy(struct fscache_object *object)
755{
756 fscache_objlist_remove(object);
757
758 /* We can get rid of the cookie now */
759 fscache_cookie_put(object->cookie);
760 object->cookie = NULL;
761}
762EXPORT_SYMBOL(fscache_object_destroy);
763
783/* 764/*
784 * enqueue an object for metadata-type processing 765 * enqueue an object for metadata-type processing
785 */ 766 */
@@ -803,7 +784,7 @@ void fscache_enqueue_object(struct fscache_object *object)
803 784
804/** 785/**
805 * fscache_object_sleep_till_congested - Sleep until object wq is congested 786 * fscache_object_sleep_till_congested - Sleep until object wq is congested
806 * @timoutp: Scheduler sleep timeout 787 * @timeoutp: Scheduler sleep timeout
807 * 788 *
808 * Allow an object handler to sleep until the object workqueue is congested. 789 * Allow an object handler to sleep until the object workqueue is congested.
809 * 790 *
@@ -831,18 +812,21 @@ bool fscache_object_sleep_till_congested(signed long *timeoutp)
831EXPORT_SYMBOL_GPL(fscache_object_sleep_till_congested); 812EXPORT_SYMBOL_GPL(fscache_object_sleep_till_congested);
832 813
833/* 814/*
834 * enqueue the dependents of an object for metadata-type processing 815 * Enqueue the dependents of an object for metadata-type processing.
835 * - the caller must hold the object's lock 816 *
836 * - this may cause an already locked object to wind up being processed again 817 * If we don't manage to finish the list before the scheduler wants to run
818 * again then return false immediately. We return true if the list was
819 * cleared.
837 */ 820 */
838static void fscache_enqueue_dependents(struct fscache_object *object) 821static bool fscache_enqueue_dependents(struct fscache_object *object, int event)
839{ 822{
840 struct fscache_object *dep; 823 struct fscache_object *dep;
824 bool ret = true;
841 825
842 _enter("{OBJ%x}", object->debug_id); 826 _enter("{OBJ%x}", object->debug_id);
843 827
844 if (list_empty(&object->dependents)) 828 if (list_empty(&object->dependents))
845 return; 829 return true;
846 830
847 spin_lock(&object->lock); 831 spin_lock(&object->lock);
848 832
@@ -851,23 +835,23 @@ static void fscache_enqueue_dependents(struct fscache_object *object)
851 struct fscache_object, dep_link); 835 struct fscache_object, dep_link);
852 list_del_init(&dep->dep_link); 836 list_del_init(&dep->dep_link);
853 837
854 838 fscache_raise_event(dep, event);
855 /* sort onto appropriate lists */
856 fscache_enqueue_object(dep);
857 fscache_put_object(dep); 839 fscache_put_object(dep);
858 840
859 if (!list_empty(&object->dependents)) 841 if (!list_empty(&object->dependents) && need_resched()) {
860 cond_resched_lock(&object->lock); 842 ret = false;
843 break;
844 }
861 } 845 }
862 846
863 spin_unlock(&object->lock); 847 spin_unlock(&object->lock);
848 return ret;
864} 849}
865 850
866/* 851/*
867 * remove an object from whatever queue it's waiting on 852 * remove an object from whatever queue it's waiting on
868 * - the caller must hold object->lock
869 */ 853 */
870void fscache_dequeue_object(struct fscache_object *object) 854static void fscache_dequeue_object(struct fscache_object *object)
871{ 855{
872 _enter("{OBJ%x}", object->debug_id); 856 _enter("{OBJ%x}", object->debug_id);
873 857
@@ -886,7 +870,10 @@ void fscache_dequeue_object(struct fscache_object *object)
886 * @data: The auxiliary data for the object 870 * @data: The auxiliary data for the object
887 * @datalen: The size of the auxiliary data 871 * @datalen: The size of the auxiliary data
888 * 872 *
889 * This function consults the netfs about the coherency state of an object 873 * This function consults the netfs about the coherency state of an object.
874 * The caller must be holding a ref on cookie->n_active (held by
875 * fscache_look_up_object() on behalf of the cache backend during object lookup
876 * and creation).
890 */ 877 */
891enum fscache_checkaux fscache_check_aux(struct fscache_object *object, 878enum fscache_checkaux fscache_check_aux(struct fscache_object *object,
892 const void *data, uint16_t datalen) 879 const void *data, uint16_t datalen)
@@ -927,12 +914,23 @@ EXPORT_SYMBOL(fscache_check_aux);
927/* 914/*
928 * Asynchronously invalidate an object. 915 * Asynchronously invalidate an object.
929 */ 916 */
930static void fscache_invalidate_object(struct fscache_object *object) 917static const struct fscache_state *_fscache_invalidate_object(struct fscache_object *object,
918 int event)
931{ 919{
932 struct fscache_operation *op; 920 struct fscache_operation *op;
933 struct fscache_cookie *cookie = object->cookie; 921 struct fscache_cookie *cookie = object->cookie;
934 922
935 _enter("{OBJ%x}", object->debug_id); 923 _enter("{OBJ%x},%d", object->debug_id, event);
924
925 /* We're going to need the cookie. If the cookie is not available then
926 * retire the object instead.
927 */
928 if (!fscache_use_cookie(object)) {
929 ASSERT(object->cookie->stores.rnode == NULL);
930 set_bit(FSCACHE_COOKIE_RETIRED, &cookie->flags);
931 _leave(" [no cookie]");
932 return transit_to(KILL_OBJECT);
933 }
936 934
937 /* Reject any new read/write ops and abort any that are pending. */ 935 /* Reject any new read/write ops and abort any that are pending. */
938 fscache_invalidate_writes(cookie); 936 fscache_invalidate_writes(cookie);
@@ -941,14 +939,13 @@ static void fscache_invalidate_object(struct fscache_object *object)
941 939
942 /* Now we have to wait for in-progress reads and writes */ 940 /* Now we have to wait for in-progress reads and writes */
943 op = kzalloc(sizeof(*op), GFP_KERNEL); 941 op = kzalloc(sizeof(*op), GFP_KERNEL);
944 if (!op) { 942 if (!op)
945 fscache_raise_event(object, FSCACHE_OBJECT_EV_ERROR); 943 goto nomem;
946 _leave(" [ENOMEM]");
947 return;
948 }
949 944
950 fscache_operation_init(op, object->cache->ops->invalidate_object, NULL); 945 fscache_operation_init(op, object->cache->ops->invalidate_object, NULL);
951 op->flags = FSCACHE_OP_ASYNC | (1 << FSCACHE_OP_EXCLUSIVE); 946 op->flags = FSCACHE_OP_ASYNC |
947 (1 << FSCACHE_OP_EXCLUSIVE) |
948 (1 << FSCACHE_OP_UNUSE_COOKIE);
952 949
953 spin_lock(&cookie->lock); 950 spin_lock(&cookie->lock);
954 if (fscache_submit_exclusive_op(object, op) < 0) 951 if (fscache_submit_exclusive_op(object, op) < 0)
@@ -965,13 +962,50 @@ static void fscache_invalidate_object(struct fscache_object *object)
965 /* We can allow read and write requests to come in once again. They'll 962 /* We can allow read and write requests to come in once again. They'll
966 * queue up behind our exclusive invalidation operation. 963 * queue up behind our exclusive invalidation operation.
967 */ 964 */
968 fscache_invalidation_complete(cookie); 965 if (test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
969 _leave(""); 966 wake_up_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING);
970 return; 967 _leave(" [ok]");
968 return transit_to(UPDATE_OBJECT);
969
970nomem:
971 clear_bit(FSCACHE_OBJECT_IS_LIVE, &object->flags);
972 fscache_unuse_cookie(object);
973 _leave(" [ENOMEM]");
974 return transit_to(KILL_OBJECT);
971 975
972submit_op_failed: 976submit_op_failed:
977 clear_bit(FSCACHE_OBJECT_IS_LIVE, &object->flags);
973 spin_unlock(&cookie->lock); 978 spin_unlock(&cookie->lock);
974 kfree(op); 979 kfree(op);
975 fscache_raise_event(object, FSCACHE_OBJECT_EV_ERROR);
976 _leave(" [EIO]"); 980 _leave(" [EIO]");
981 return transit_to(KILL_OBJECT);
982}
983
984static const struct fscache_state *fscache_invalidate_object(struct fscache_object *object,
985 int event)
986{
987 const struct fscache_state *s;
988
989 fscache_stat(&fscache_n_invalidates_run);
990 fscache_stat(&fscache_n_cop_invalidate_object);
991 s = _fscache_invalidate_object(object, event);
992 fscache_stat_d(&fscache_n_cop_invalidate_object);
993 return s;
994}
995
996/*
997 * Asynchronously update an object.
998 */
999static const struct fscache_state *fscache_update_object(struct fscache_object *object,
1000 int event)
1001{
1002 _enter("{OBJ%x},%d", object->debug_id, event);
1003
1004 fscache_stat(&fscache_n_updates_run);
1005 fscache_stat(&fscache_n_cop_update_object);
1006 object->cache->ops->update_object(object);
1007 fscache_stat_d(&fscache_n_cop_update_object);
1008
1009 _leave("");
1010 return transit_to(WAIT_FOR_CMD);
977} 1011}
diff --git a/fs/fscache/operation.c b/fs/fscache/operation.c
index 762a9ec4ffa4..318071aca217 100644
--- a/fs/fscache/operation.c
+++ b/fs/fscache/operation.c
@@ -35,7 +35,7 @@ void fscache_enqueue_operation(struct fscache_operation *op)
35 35
36 ASSERT(list_empty(&op->pend_link)); 36 ASSERT(list_empty(&op->pend_link));
37 ASSERT(op->processor != NULL); 37 ASSERT(op->processor != NULL);
38 ASSERTCMP(op->object->state, >=, FSCACHE_OBJECT_AVAILABLE); 38 ASSERT(fscache_object_is_available(op->object));
39 ASSERTCMP(atomic_read(&op->usage), >, 0); 39 ASSERTCMP(atomic_read(&op->usage), >, 0);
40 ASSERTCMP(op->state, ==, FSCACHE_OP_ST_IN_PROGRESS); 40 ASSERTCMP(op->state, ==, FSCACHE_OP_ST_IN_PROGRESS);
41 41
@@ -119,7 +119,7 @@ int fscache_submit_exclusive_op(struct fscache_object *object,
119 /* need to issue a new write op after this */ 119 /* need to issue a new write op after this */
120 clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags); 120 clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags);
121 ret = 0; 121 ret = 0;
122 } else if (object->state == FSCACHE_OBJECT_CREATING) { 122 } else if (test_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags)) {
123 op->object = object; 123 op->object = object;
124 object->n_ops++; 124 object->n_ops++;
125 object->n_exclusive++; /* reads and writes must wait */ 125 object->n_exclusive++; /* reads and writes must wait */
@@ -144,7 +144,7 @@ int fscache_submit_exclusive_op(struct fscache_object *object,
144 */ 144 */
145static void fscache_report_unexpected_submission(struct fscache_object *object, 145static void fscache_report_unexpected_submission(struct fscache_object *object,
146 struct fscache_operation *op, 146 struct fscache_operation *op,
147 unsigned long ostate) 147 const struct fscache_state *ostate)
148{ 148{
149 static bool once_only; 149 static bool once_only;
150 struct fscache_operation *p; 150 struct fscache_operation *p;
@@ -155,11 +155,8 @@ static void fscache_report_unexpected_submission(struct fscache_object *object,
155 once_only = true; 155 once_only = true;
156 156
157 kdebug("unexpected submission OP%x [OBJ%x %s]", 157 kdebug("unexpected submission OP%x [OBJ%x %s]",
158 op->debug_id, object->debug_id, 158 op->debug_id, object->debug_id, object->state->name);
159 fscache_object_states[object->state]); 159 kdebug("objstate=%s [%s]", object->state->name, ostate->name);
160 kdebug("objstate=%s [%s]",
161 fscache_object_states[object->state],
162 fscache_object_states[ostate]);
163 kdebug("objflags=%lx", object->flags); 160 kdebug("objflags=%lx", object->flags);
164 kdebug("objevent=%lx [%lx]", object->events, object->event_mask); 161 kdebug("objevent=%lx [%lx]", object->events, object->event_mask);
165 kdebug("ops=%u inp=%u exc=%u", 162 kdebug("ops=%u inp=%u exc=%u",
@@ -190,7 +187,7 @@ static void fscache_report_unexpected_submission(struct fscache_object *object,
190int fscache_submit_op(struct fscache_object *object, 187int fscache_submit_op(struct fscache_object *object,
191 struct fscache_operation *op) 188 struct fscache_operation *op)
192{ 189{
193 unsigned long ostate; 190 const struct fscache_state *ostate;
194 int ret; 191 int ret;
195 192
196 _enter("{OBJ%x OP%x},{%u}", 193 _enter("{OBJ%x OP%x},{%u}",
@@ -226,16 +223,14 @@ int fscache_submit_op(struct fscache_object *object,
226 fscache_run_op(object, op); 223 fscache_run_op(object, op);
227 } 224 }
228 ret = 0; 225 ret = 0;
229 } else if (object->state == FSCACHE_OBJECT_CREATING) { 226 } else if (test_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags)) {
230 op->object = object; 227 op->object = object;
231 object->n_ops++; 228 object->n_ops++;
232 atomic_inc(&op->usage); 229 atomic_inc(&op->usage);
233 list_add_tail(&op->pend_link, &object->pending_ops); 230 list_add_tail(&op->pend_link, &object->pending_ops);
234 fscache_stat(&fscache_n_op_pend); 231 fscache_stat(&fscache_n_op_pend);
235 ret = 0; 232 ret = 0;
236 } else if (object->state == FSCACHE_OBJECT_DYING || 233 } else if (fscache_object_is_dying(object)) {
237 object->state == FSCACHE_OBJECT_LC_DYING ||
238 object->state == FSCACHE_OBJECT_WITHDRAWING) {
239 fscache_stat(&fscache_n_op_rejected); 234 fscache_stat(&fscache_n_op_rejected);
240 op->state = FSCACHE_OP_ST_CANCELLED; 235 op->state = FSCACHE_OP_ST_CANCELLED;
241 ret = -ENOBUFS; 236 ret = -ENOBUFS;
@@ -265,8 +260,8 @@ void fscache_abort_object(struct fscache_object *object)
265} 260}
266 261
267/* 262/*
268 * jump start the operation processing on an object 263 * Jump start the operation processing on an object. The caller must hold
269 * - caller must hold object->lock 264 * object->lock.
270 */ 265 */
271void fscache_start_operations(struct fscache_object *object) 266void fscache_start_operations(struct fscache_object *object)
272{ 267{
@@ -428,14 +423,10 @@ void fscache_put_operation(struct fscache_operation *op)
428 423
429 object = op->object; 424 object = op->object;
430 425
431 if (test_bit(FSCACHE_OP_DEC_READ_CNT, &op->flags)) { 426 if (test_bit(FSCACHE_OP_DEC_READ_CNT, &op->flags))
432 if (atomic_dec_and_test(&object->n_reads)) { 427 atomic_dec(&object->n_reads);
433 clear_bit(FSCACHE_COOKIE_WAITING_ON_READS, 428 if (test_bit(FSCACHE_OP_UNUSE_COOKIE, &op->flags))
434 &object->cookie->flags); 429 fscache_unuse_cookie(object);
435 wake_up_bit(&object->cookie->flags,
436 FSCACHE_COOKIE_WAITING_ON_READS);
437 }
438 }
439 430
440 /* now... we may get called with the object spinlock held, so we 431 /* now... we may get called with the object spinlock held, so we
441 * complete the cleanup here only if we can immediately acquire the 432 * complete the cleanup here only if we can immediately acquire the
diff --git a/fs/fscache/page.c b/fs/fscache/page.c
index ff000e52072d..d479ab3c63e4 100644
--- a/fs/fscache/page.c
+++ b/fs/fscache/page.c
@@ -109,7 +109,7 @@ page_busy:
109 * allocator as the work threads writing to the cache may all end up 109 * allocator as the work threads writing to the cache may all end up
110 * sleeping on memory allocation, so we may need to impose a timeout 110 * sleeping on memory allocation, so we may need to impose a timeout
111 * too. */ 111 * too. */
112 if (!(gfp & __GFP_WAIT)) { 112 if (!(gfp & __GFP_WAIT) || !(gfp & __GFP_FS)) {
113 fscache_stat(&fscache_n_store_vmscan_busy); 113 fscache_stat(&fscache_n_store_vmscan_busy);
114 return false; 114 return false;
115 } 115 }
@@ -163,10 +163,12 @@ static void fscache_attr_changed_op(struct fscache_operation *op)
163 163
164 fscache_stat(&fscache_n_attr_changed_calls); 164 fscache_stat(&fscache_n_attr_changed_calls);
165 165
166 if (fscache_object_is_active(object)) { 166 if (fscache_object_is_active(object) &&
167 fscache_use_cookie(object)) {
167 fscache_stat(&fscache_n_cop_attr_changed); 168 fscache_stat(&fscache_n_cop_attr_changed);
168 ret = object->cache->ops->attr_changed(object); 169 ret = object->cache->ops->attr_changed(object);
169 fscache_stat_d(&fscache_n_cop_attr_changed); 170 fscache_stat_d(&fscache_n_cop_attr_changed);
171 fscache_unuse_cookie(object);
170 if (ret < 0) 172 if (ret < 0)
171 fscache_abort_object(object); 173 fscache_abort_object(object);
172 } 174 }
@@ -233,7 +235,7 @@ static void fscache_release_retrieval_op(struct fscache_operation *_op)
233 235
234 _enter("{OP%x}", op->op.debug_id); 236 _enter("{OP%x}", op->op.debug_id);
235 237
236 ASSERTCMP(op->n_pages, ==, 0); 238 ASSERTCMP(atomic_read(&op->n_pages), ==, 0);
237 239
238 fscache_hist(fscache_retrieval_histogram, op->start_time); 240 fscache_hist(fscache_retrieval_histogram, op->start_time);
239 if (op->context) 241 if (op->context)
@@ -246,6 +248,7 @@ static void fscache_release_retrieval_op(struct fscache_operation *_op)
246 * allocate a retrieval op 248 * allocate a retrieval op
247 */ 249 */
248static struct fscache_retrieval *fscache_alloc_retrieval( 250static struct fscache_retrieval *fscache_alloc_retrieval(
251 struct fscache_cookie *cookie,
249 struct address_space *mapping, 252 struct address_space *mapping,
250 fscache_rw_complete_t end_io_func, 253 fscache_rw_complete_t end_io_func,
251 void *context) 254 void *context)
@@ -260,7 +263,10 @@ static struct fscache_retrieval *fscache_alloc_retrieval(
260 } 263 }
261 264
262 fscache_operation_init(&op->op, NULL, fscache_release_retrieval_op); 265 fscache_operation_init(&op->op, NULL, fscache_release_retrieval_op);
263 op->op.flags = FSCACHE_OP_MYTHREAD | (1 << FSCACHE_OP_WAITING); 266 atomic_inc(&cookie->n_active);
267 op->op.flags = FSCACHE_OP_MYTHREAD |
268 (1UL << FSCACHE_OP_WAITING) |
269 (1UL << FSCACHE_OP_UNUSE_COOKIE);
264 op->mapping = mapping; 270 op->mapping = mapping;
265 op->end_io_func = end_io_func; 271 op->end_io_func = end_io_func;
266 op->context = context; 272 op->context = context;
@@ -310,7 +316,7 @@ static void fscache_do_cancel_retrieval(struct fscache_operation *_op)
310 struct fscache_retrieval *op = 316 struct fscache_retrieval *op =
311 container_of(_op, struct fscache_retrieval, op); 317 container_of(_op, struct fscache_retrieval, op);
312 318
313 op->n_pages = 0; 319 atomic_set(&op->n_pages, 0);
314} 320}
315 321
316/* 322/*
@@ -394,12 +400,13 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie,
394 if (fscache_wait_for_deferred_lookup(cookie) < 0) 400 if (fscache_wait_for_deferred_lookup(cookie) < 0)
395 return -ERESTARTSYS; 401 return -ERESTARTSYS;
396 402
397 op = fscache_alloc_retrieval(page->mapping, end_io_func, context); 403 op = fscache_alloc_retrieval(cookie, page->mapping,
404 end_io_func,context);
398 if (!op) { 405 if (!op) {
399 _leave(" = -ENOMEM"); 406 _leave(" = -ENOMEM");
400 return -ENOMEM; 407 return -ENOMEM;
401 } 408 }
402 op->n_pages = 1; 409 atomic_set(&op->n_pages, 1);
403 410
404 spin_lock(&cookie->lock); 411 spin_lock(&cookie->lock);
405 412
@@ -408,7 +415,7 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie,
408 object = hlist_entry(cookie->backing_objects.first, 415 object = hlist_entry(cookie->backing_objects.first,
409 struct fscache_object, cookie_link); 416 struct fscache_object, cookie_link);
410 417
411 ASSERTCMP(object->state, >, FSCACHE_OBJECT_LOOKING_UP); 418 ASSERT(test_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags));
412 419
413 atomic_inc(&object->n_reads); 420 atomic_inc(&object->n_reads);
414 __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags); 421 __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags);
@@ -465,6 +472,7 @@ nobufs_unlock_dec:
465 atomic_dec(&object->n_reads); 472 atomic_dec(&object->n_reads);
466nobufs_unlock: 473nobufs_unlock:
467 spin_unlock(&cookie->lock); 474 spin_unlock(&cookie->lock);
475 atomic_dec(&cookie->n_active);
468 kfree(op); 476 kfree(op);
469nobufs: 477nobufs:
470 fscache_stat(&fscache_n_retrievals_nobufs); 478 fscache_stat(&fscache_n_retrievals_nobufs);
@@ -522,10 +530,10 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
522 if (fscache_wait_for_deferred_lookup(cookie) < 0) 530 if (fscache_wait_for_deferred_lookup(cookie) < 0)
523 return -ERESTARTSYS; 531 return -ERESTARTSYS;
524 532
525 op = fscache_alloc_retrieval(mapping, end_io_func, context); 533 op = fscache_alloc_retrieval(cookie, mapping, end_io_func, context);
526 if (!op) 534 if (!op)
527 return -ENOMEM; 535 return -ENOMEM;
528 op->n_pages = *nr_pages; 536 atomic_set(&op->n_pages, *nr_pages);
529 537
530 spin_lock(&cookie->lock); 538 spin_lock(&cookie->lock);
531 539
@@ -589,6 +597,7 @@ nobufs_unlock_dec:
589 atomic_dec(&object->n_reads); 597 atomic_dec(&object->n_reads);
590nobufs_unlock: 598nobufs_unlock:
591 spin_unlock(&cookie->lock); 599 spin_unlock(&cookie->lock);
600 atomic_dec(&cookie->n_active);
592 kfree(op); 601 kfree(op);
593nobufs: 602nobufs:
594 fscache_stat(&fscache_n_retrievals_nobufs); 603 fscache_stat(&fscache_n_retrievals_nobufs);
@@ -631,10 +640,10 @@ int __fscache_alloc_page(struct fscache_cookie *cookie,
631 if (fscache_wait_for_deferred_lookup(cookie) < 0) 640 if (fscache_wait_for_deferred_lookup(cookie) < 0)
632 return -ERESTARTSYS; 641 return -ERESTARTSYS;
633 642
634 op = fscache_alloc_retrieval(page->mapping, NULL, NULL); 643 op = fscache_alloc_retrieval(cookie, page->mapping, NULL, NULL);
635 if (!op) 644 if (!op)
636 return -ENOMEM; 645 return -ENOMEM;
637 op->n_pages = 1; 646 atomic_set(&op->n_pages, 1);
638 647
639 spin_lock(&cookie->lock); 648 spin_lock(&cookie->lock);
640 649
@@ -675,6 +684,7 @@ error:
675 684
676nobufs_unlock: 685nobufs_unlock:
677 spin_unlock(&cookie->lock); 686 spin_unlock(&cookie->lock);
687 atomic_dec(&cookie->n_active);
678 kfree(op); 688 kfree(op);
679nobufs: 689nobufs:
680 fscache_stat(&fscache_n_allocs_nobufs); 690 fscache_stat(&fscache_n_allocs_nobufs);
@@ -729,8 +739,9 @@ static void fscache_write_op(struct fscache_operation *_op)
729 */ 739 */
730 spin_unlock(&object->lock); 740 spin_unlock(&object->lock);
731 fscache_op_complete(&op->op, false); 741 fscache_op_complete(&op->op, false);
732 _leave(" [cancel] op{f=%lx s=%u} obj{s=%u f=%lx}", 742 _leave(" [cancel] op{f=%lx s=%u} obj{s=%s f=%lx}",
733 _op->flags, _op->state, object->state, object->flags); 743 _op->flags, _op->state, object->state->short_name,
744 object->flags);
734 return; 745 return;
735 } 746 }
736 747
@@ -796,11 +807,16 @@ void fscache_invalidate_writes(struct fscache_cookie *cookie)
796 807
797 _enter(""); 808 _enter("");
798 809
799 while (spin_lock(&cookie->stores_lock), 810 for (;;) {
800 n = radix_tree_gang_lookup_tag(&cookie->stores, results, 0, 811 spin_lock(&cookie->stores_lock);
801 ARRAY_SIZE(results), 812 n = radix_tree_gang_lookup_tag(&cookie->stores, results, 0,
802 FSCACHE_COOKIE_PENDING_TAG), 813 ARRAY_SIZE(results),
803 n > 0) { 814 FSCACHE_COOKIE_PENDING_TAG);
815 if (n == 0) {
816 spin_unlock(&cookie->stores_lock);
817 break;
818 }
819
804 for (i = n - 1; i >= 0; i--) { 820 for (i = n - 1; i >= 0; i--) {
805 page = results[i]; 821 page = results[i];
806 radix_tree_delete(&cookie->stores, page->index); 822 radix_tree_delete(&cookie->stores, page->index);
@@ -812,7 +828,6 @@ void fscache_invalidate_writes(struct fscache_cookie *cookie)
812 page_cache_release(results[i]); 828 page_cache_release(results[i]);
813 } 829 }
814 830
815 spin_unlock(&cookie->stores_lock);
816 _leave(""); 831 _leave("");
817} 832}
818 833
@@ -829,14 +844,12 @@ void fscache_invalidate_writes(struct fscache_cookie *cookie)
829 * (1) negative lookup, object not yet created (FSCACHE_COOKIE_CREATING is 844 * (1) negative lookup, object not yet created (FSCACHE_COOKIE_CREATING is
830 * set) 845 * set)
831 * 846 *
832 * (a) no writes yet (set FSCACHE_COOKIE_PENDING_FILL and queue deferred 847 * (a) no writes yet
833 * fill op)
834 * 848 *
835 * (b) writes deferred till post-creation (mark page for writing and 849 * (b) writes deferred till post-creation (mark page for writing and
836 * return immediately) 850 * return immediately)
837 * 851 *
838 * (2) negative lookup, object created, initial fill being made from netfs 852 * (2) negative lookup, object created, initial fill being made from netfs
839 * (FSCACHE_COOKIE_INITIAL_FILL is set)
840 * 853 *
841 * (a) fill point not yet reached this page (mark page for writing and 854 * (a) fill point not yet reached this page (mark page for writing and
842 * return) 855 * return)
@@ -873,7 +886,9 @@ int __fscache_write_page(struct fscache_cookie *cookie,
873 886
874 fscache_operation_init(&op->op, fscache_write_op, 887 fscache_operation_init(&op->op, fscache_write_op,
875 fscache_release_write_op); 888 fscache_release_write_op);
876 op->op.flags = FSCACHE_OP_ASYNC | (1 << FSCACHE_OP_WAITING); 889 op->op.flags = FSCACHE_OP_ASYNC |
890 (1 << FSCACHE_OP_WAITING) |
891 (1 << FSCACHE_OP_UNUSE_COOKIE);
877 892
878 ret = radix_tree_preload(gfp & ~__GFP_HIGHMEM); 893 ret = radix_tree_preload(gfp & ~__GFP_HIGHMEM);
879 if (ret < 0) 894 if (ret < 0)
@@ -919,6 +934,7 @@ int __fscache_write_page(struct fscache_cookie *cookie,
919 op->op.debug_id = atomic_inc_return(&fscache_op_debug_id); 934 op->op.debug_id = atomic_inc_return(&fscache_op_debug_id);
920 op->store_limit = object->store_limit; 935 op->store_limit = object->store_limit;
921 936
937 atomic_inc(&cookie->n_active);
922 if (fscache_submit_op(object, &op->op) < 0) 938 if (fscache_submit_op(object, &op->op) < 0)
923 goto submit_failed; 939 goto submit_failed;
924 940
@@ -945,6 +961,7 @@ already_pending:
945 return 0; 961 return 0;
946 962
947submit_failed: 963submit_failed:
964 atomic_dec(&cookie->n_active);
948 spin_lock(&cookie->stores_lock); 965 spin_lock(&cookie->stores_lock);
949 radix_tree_delete(&cookie->stores, page->index); 966 radix_tree_delete(&cookie->stores, page->index);
950 spin_unlock(&cookie->stores_lock); 967 spin_unlock(&cookie->stores_lock);
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-16 00:42:16 -0500