fs/cachefiles/daemon.c

61 	int (*handler)(struct cachefiles_cache *cache, char *args);
87  * Prepare a cache for caching.
91 	struct cachefiles_cache *cache;
103 	/* allocate a cache record */
104 	cache = kzalloc(sizeof(struct cachefiles_cache), GFP_KERNEL);
105 	if (!cache) {
110 	mutex_init(&cache->daemon_mutex);
111 	init_waitqueue_head(&cache->daemon_pollwq);
112 	INIT_LIST_HEAD(&cache->volumes);
113 	INIT_LIST_HEAD(&cache->object_list);
114 	spin_lock_init(&cache->object_list_lock);
115 	refcount_set(&cache->unbind_pincount, 1);
116 	xa_init_flags(&cache->reqs, XA_FLAGS_ALLOC);
117 	xa_init_flags(&cache->ondemand_ids, XA_FLAGS_ALLOC1);
124 	cache->frun_percent = 7;
125 	cache->fcull_percent = 5;
126 	cache->fstop_percent = 1;
127 	cache->brun_percent = 7;
128 	cache->bcull_percent = 5;
129 	cache->bstop_percent = 1;
131 	file->private_data = cache;
132 	cache->cachefilesd = file;
136 static void cachefiles_flush_reqs(struct cachefiles_cache *cache)
138 	struct xarray *xa = &cache->reqs;
165 	xa_destroy(&cache->reqs);
166 	xa_destroy(&cache->ondemand_ids);
169 void cachefiles_put_unbind_pincount(struct cachefiles_cache *cache)
171 	if (refcount_dec_and_test(&cache->unbind_pincount)) {
172 		cachefiles_daemon_unbind(cache);
174 		kfree(cache);
178 void cachefiles_get_unbind_pincount(struct cachefiles_cache *cache)
180 	refcount_inc(&cache->unbind_pincount);
184  * Release a cache.
188 	struct cachefiles_cache *cache = file->private_data;
192 	ASSERT(cache);
194 	set_bit(CACHEFILES_DEAD, &cache->flags);
196 	if (cachefiles_in_ondemand_mode(cache))
197 		cachefiles_flush_reqs(cache);
200 	cache->cachefilesd = NULL;
203 	cachefiles_put_unbind_pincount(cache);
209 static ssize_t cachefiles_do_daemon_read(struct cachefiles_cache *cache,
217 	/* check how much space the cache has */
218 	cachefiles_has_space(cache, 0, 0, cachefiles_has_space_check);
221 	f_released = atomic_xchg(&cache->f_released, 0);
222 	b_released = atomic_long_xchg(&cache->b_released, 0);
223 	clear_bit(CACHEFILES_STATE_CHANGED, &cache->flags);
235 		     test_bit(CACHEFILES_CULLING, &cache->flags) ? '1' : '0',
236 		     (unsigned long long) cache->frun,
237 		     (unsigned long long) cache->fcull,
238 		     (unsigned long long) cache->fstop,
239 		     (unsigned long long) cache->brun,
240 		     (unsigned long long) cache->bcull,
241 		     (unsigned long long) cache->bstop,
255  * Read the cache state.
260 	struct cachefiles_cache *cache = file->private_data;
264 	if (!test_bit(CACHEFILES_READY, &cache->flags))
267 	if (cachefiles_in_ondemand_mode(cache))
268 		return cachefiles_ondemand_daemon_read(cache, _buffer, buflen);
270 		return cachefiles_do_daemon_read(cache, _buffer, buflen);
282 	struct cachefiles_cache *cache = file->private_data;
288 	ASSERT(cache);
290 	if (test_bit(CACHEFILES_DEAD, &cache->flags))
338 	mutex_lock(&cache->daemon_mutex);
341 	if (!test_bit(CACHEFILES_DEAD, &cache->flags))
342 		ret = cmd->handler(cache, args);
344 	mutex_unlock(&cache->daemon_mutex);
358 	struct cachefiles_cache *cache = file->private_data;
359 	XA_STATE(xas, &cache->reqs, 0);
363 	poll_wait(file, &cache->daemon_pollwq, poll);
366 	if (cachefiles_in_ondemand_mode(cache)) {
367 		if (!xa_empty(&cache->reqs)) {
378 		if (test_bit(CACHEFILES_STATE_CHANGED, &cache->flags))
382 	if (test_bit(CACHEFILES_CULLING, &cache->flags))
389  * Give a range error for cache space constraints
392 static int cachefiles_daemon_range_error(struct cachefiles_cache *cache,
404 static int cachefiles_daemon_frun(struct cachefiles_cache *cache, char *args)
417 	if (frun <= cache->fcull_percent || frun >= 100)
418 		return cachefiles_daemon_range_error(cache, args);
420 	cache->frun_percent = frun;
428 static int cachefiles_daemon_fcull(struct cachefiles_cache *cache, char *args)
441 	if (fcull <= cache->fstop_percent || fcull >= cache->frun_percent)
442 		return cachefiles_daemon_range_error(cache, args);
444 	cache->fcull_percent = fcull;
452 static int cachefiles_daemon_fstop(struct cachefiles_cache *cache, char *args)
465 	if (fstop >= cache->fcull_percent)
466 		return cachefiles_daemon_range_error(cache, args);
468 	cache->fstop_percent = fstop;
476 static int cachefiles_daemon_brun(struct cachefiles_cache *cache, char *args)
489 	if (brun <= cache->bcull_percent || brun >= 100)
490 		return cachefiles_daemon_range_error(cache, args);
492 	cache->brun_percent = brun;
500 static int cachefiles_daemon_bcull(struct cachefiles_cache *cache, char *args)
513 	if (bcull <= cache->bstop_percent || bcull >= cache->brun_percent)
514 		return cachefiles_daemon_range_error(cache, args);
516 	cache->bcull_percent = bcull;
524 static int cachefiles_daemon_bstop(struct cachefiles_cache *cache, char *args)
537 	if (bstop >= cache->bcull_percent)
538 		return cachefiles_daemon_range_error(cache, args);
540 	cache->bstop_percent = bstop;
545  * Set the cache directory
548 static int cachefiles_daemon_dir(struct cachefiles_cache *cache, char *args)
559 	if (cache->rootdirname) {
560 		pr_err("Second cache directory specified\n");
568 	cache->rootdirname = dir;
573  * Set the cache security context
576 static int cachefiles_daemon_secctx(struct cachefiles_cache *cache, char *args)
587 	if (cache->secctx) {
596 	cache->secctx = secctx;
601  * Set the cache tag
604 static int cachefiles_daemon_tag(struct cachefiles_cache *cache, char *args)
615 	if (cache->tag)
622 	cache->tag = tag;
627  * Request a node in the cache be culled from the current working directory
630 static int cachefiles_daemon_cull(struct cachefiles_cache *cache, char *args)
641 	if (!test_bit(CACHEFILES_READY, &cache->flags)) {
642 		pr_err("cull applied to unready cache\n");
646 	if (test_bit(CACHEFILES_DEAD, &cache->flags)) {
647 		pr_err("cull applied to dead cache\n");
656 	cachefiles_begin_secure(cache, &saved_cred);
657 	ret = cachefiles_cull(cache, path.dentry, args);
658 	cachefiles_end_secure(cache, saved_cred);
678 static int cachefiles_daemon_debug(struct cachefiles_cache *cache, char *args)
701 static int cachefiles_daemon_inuse(struct cachefiles_cache *cache, char *args)
712 	if (!test_bit(CACHEFILES_READY, &cache->flags)) {
713 		pr_err("inuse applied to unready cache\n");
717 	if (test_bit(CACHEFILES_DEAD, &cache->flags)) {
718 		pr_err("inuse applied to dead cache\n");
727 	cachefiles_begin_secure(cache, &saved_cred);
728 	ret = cachefiles_check_in_use(cache, path.dentry, args);
729 	cachefiles_end_secure(cache, saved_cred);
746  * Bind a directory as a cache
748 static int cachefiles_daemon_bind(struct cachefiles_cache *cache, char *args)
751 	       cache->frun_percent,
752 	       cache->fcull_percent,
753 	       cache->fstop_percent,
754 	       cache->brun_percent,
755 	       cache->bcull_percent,
756 	       cache->bstop_percent,
759 	if (cache->fstop_percent >= cache->fcull_percent ||
760 	    cache->fcull_percent >= cache->frun_percent ||
761 	    cache->frun_percent  >= 100)
764 	if (cache->bstop_percent >= cache->bcull_percent ||
765 	    cache->bcull_percent >= cache->brun_percent ||
766 	    cache->brun_percent  >= 100)
769 	if (!cache->rootdirname) {
770 		pr_err("No cache directory specified\n");
775 	if (test_bit(CACHEFILES_READY, &cache->flags)) {
782 			set_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags);
793 	if (!cache->tag) {
798 		cache->tag = kstrdup("CacheFiles", GFP_KERNEL);
799 		if (!cache->tag)
803 	return cachefiles_add_cache(cache);
807  * Unbind a cache.
809 static void cachefiles_daemon_unbind(struct cachefiles_cache *cache)
813 	if (test_bit(CACHEFILES_READY, &cache->flags))
814 		cachefiles_withdraw_cache(cache);
816 	cachefiles_put_directory(cache->graveyard);
817 	cachefiles_put_directory(cache->store);
818 	mntput(cache->mnt);
819 	put_cred(cache->cache_cred);
821 	kfree(cache->rootdirname);
822 	kfree(cache->secctx);
823 	kfree(cache->tag);