2 /* Manage high-level VFS aspects of a cache.
15  * Bring a cache online.
17 int cachefiles_add_cache(struct cachefiles_cache *cache)  in cachefiles_add_cache()  argument
28 	cache_cookie = fscache_acquire_cache(cache->tag);  in cachefiles_add_cache()
33 	ret = cachefiles_get_security_ID(cache);  in cachefiles_add_cache()
37 	cachefiles_begin_secure(cache, &saved_cred);  in cachefiles_add_cache()
39 	/* look up the directory at the root of the cache */  in cachefiles_add_cache()
40 	ret = kern_path(cache->rootdirname, LOOKUP_DIRECTORY, &path);  in cachefiles_add_cache()
44 	cache->mnt = path.mnt;  in cachefiles_add_cache()
49 		pr_warn("File cache on idmapped mounts not supported");  in cachefiles_add_cache()
58 	 * - We want to be able to sync the filesystem when stopping the cache  in cachefiles_add_cache()
76 	/* determine the security of the on-disk cache as this governs  in cachefiles_add_cache()
78 	ret = cachefiles_determine_cache_security(cache, root, &saved_cred);  in cachefiles_add_cache()
82 	/* get the cache size and blocksize */  in cachefiles_add_cache()
95 	cache->bsize = stats.f_bsize;  in cachefiles_add_cache()
96 	cache->bshift = ilog2(stats.f_bsize);  in cachefiles_add_cache()
99 	       cache->bsize, cache->bshift);  in cachefiles_add_cache()
107 	cache->fstop = stats.f_files * cache->fstop_percent;  in cachefiles_add_cache()
108 	cache->fcull = stats.f_files * cache->fcull_percent;  in cachefiles_add_cache()
109 	cache->frun  = stats.f_files * cache->frun_percent;  in cachefiles_add_cache()
112 	       (unsigned long long) cache->frun,  in cachefiles_add_cache()
113 	       (unsigned long long) cache->fcull,  in cachefiles_add_cache()
114 	       (unsigned long long) cache->fstop);  in cachefiles_add_cache()
117 	cache->bstop = stats.f_blocks * cache->bstop_percent;  in cachefiles_add_cache()
118 	cache->bcull = stats.f_blocks * cache->bcull_percent;  in cachefiles_add_cache()
119 	cache->brun  = stats.f_blocks * cache->brun_percent;  in cachefiles_add_cache()
122 	       (unsigned long long) cache->brun,  in cachefiles_add_cache()
123 	       (unsigned long long) cache->bcull,  in cachefiles_add_cache()
124 	       (unsigned long long) cache->bstop);  in cachefiles_add_cache()
126 	/* get the cache directory and check its type */  in cachefiles_add_cache()
127 	cachedir = cachefiles_get_directory(cache, root, "cache", NULL);  in cachefiles_add_cache()
133 	cache->store = cachedir;  in cachefiles_add_cache()
136 	graveyard = cachefiles_get_directory(cache, root, "graveyard", NULL);  in cachefiles_add_cache()
142 	cache->graveyard = graveyard;  in cachefiles_add_cache()
143 	cache->cache = cache_cookie;  in cachefiles_add_cache()
145 	ret = fscache_add_cache(cache_cookie, &cachefiles_cache_ops, cache);  in cachefiles_add_cache()
150 	set_bit(CACHEFILES_READY, &cache->flags);  in cachefiles_add_cache()
153 	pr_info("File cache on %s registered\n", cache_cookie->name);  in cachefiles_add_cache()
155 	/* check how much space the cache has */  in cachefiles_add_cache()
156 	cachefiles_has_space(cache, 0, 0, cachefiles_has_space_check);  in cachefiles_add_cache()
157 	cachefiles_end_secure(cache, saved_cred);  in cachefiles_add_cache()
158 	_leave(" = 0 [%px]", cache->cache);  in cachefiles_add_cache()
162 	cachefiles_put_directory(cache->graveyard);  in cachefiles_add_cache()
163 	cache->graveyard = NULL;  in cachefiles_add_cache()
165 	cachefiles_put_directory(cache->store);  in cachefiles_add_cache()
166 	cache->store = NULL;  in cachefiles_add_cache()
167 	mntput(cache->mnt);  in cachefiles_add_cache()
168 	cache->mnt = NULL;  in cachefiles_add_cache()
171 	cachefiles_end_secure(cache, saved_cred);  in cachefiles_add_cache()
172 	put_cred(cache->cache_cred);  in cachefiles_add_cache()
173 	cache->cache_cred = NULL;  in cachefiles_add_cache()
176 	cache->cache = NULL;  in cachefiles_add_cache()
183  * cache
185 int cachefiles_has_space(struct cachefiles_cache *cache,  in cachefiles_has_space()  argument
194 		.mnt	= cache->mnt,  in cachefiles_has_space()
195 		.dentry	= cache->mnt->mnt_root,  in cachefiles_has_space()
199 	//       (unsigned long long) cache->frun,  in cachefiles_has_space()
200 	//       (unsigned long long) cache->fcull,  in cachefiles_has_space()
201 	//       (unsigned long long) cache->fstop,  in cachefiles_has_space()
202 	//       (unsigned long long) cache->brun,  in cachefiles_has_space()
203 	//       (unsigned long long) cache->bcull,  in cachefiles_has_space()
204 	//       (unsigned long long) cache->bstop,  in cachefiles_has_space()
215 			cachefiles_io_error(cache, "statfs failed");  in cachefiles_has_space()
221 	b_writing = atomic_long_read(&cache->b_writing);  in cachefiles_has_space()
243 	if (stats.f_ffree < cache->fstop ||  in cachefiles_has_space()
244 	    b_avail < cache->bstop)  in cachefiles_has_space()
248 	if (stats.f_ffree < cache->fcull ||  in cachefiles_has_space()
249 	    b_avail < cache->bcull)  in cachefiles_has_space()
252 	if (test_bit(CACHEFILES_CULLING, &cache->flags) &&  in cachefiles_has_space()
253 	    stats.f_ffree >= cache->frun &&  in cachefiles_has_space()
254 	    b_avail >= cache->brun &&  in cachefiles_has_space()
255 	    test_and_clear_bit(CACHEFILES_CULLING, &cache->flags)  in cachefiles_has_space()
258 		cachefiles_state_changed(cache);  in cachefiles_has_space()
276 	if (!test_and_set_bit(CACHEFILES_CULLING, &cache->flags)) {  in cachefiles_has_space()
277 		_debug("### CULL CACHE ###");  in cachefiles_has_space()
278 		cachefiles_state_changed(cache);  in cachefiles_has_space()
288 static void cachefiles_withdraw_objects(struct cachefiles_cache *cache)  in cachefiles_withdraw_objects()  argument
295 	spin_lock(&cache->object_list_lock);  in cachefiles_withdraw_objects()
297 	while (!list_empty(&cache->object_list)) {  in cachefiles_withdraw_objects()
298 		object = list_first_entry(&cache->object_list,  in cachefiles_withdraw_objects()
305 			spin_unlock(&cache->object_list_lock);  in cachefiles_withdraw_objects()
307 			spin_lock(&cache->object_list_lock);  in cachefiles_withdraw_objects()
311 	spin_unlock(&cache->object_list_lock);  in cachefiles_withdraw_objects()
318 static void cachefiles_withdraw_fscache_volumes(struct cachefiles_cache *cache)  in cachefiles_withdraw_fscache_volumes()  argument
326 	spin_lock(&cache->object_list_lock);  in cachefiles_withdraw_fscache_volumes()
327 	list_for_each(cur, &cache->volumes) {  in cachefiles_withdraw_fscache_volumes()
336 			spin_unlock(&cache->object_list_lock);  in cachefiles_withdraw_fscache_volumes()
342 	spin_unlock(&cache->object_list_lock);  in cachefiles_withdraw_fscache_volumes()
350 static void cachefiles_withdraw_volumes(struct cachefiles_cache *cache)  in cachefiles_withdraw_volumes()  argument
358 		spin_lock(&cache->object_list_lock);  in cachefiles_withdraw_volumes()
359 		if (!list_empty(&cache->volumes)) {  in cachefiles_withdraw_volumes()
360 			volume = list_first_entry(&cache->volumes,  in cachefiles_withdraw_volumes()
365 				spin_unlock(&cache->object_list_lock);  in cachefiles_withdraw_volumes()
371 		spin_unlock(&cache->object_list_lock);  in cachefiles_withdraw_volumes()
383  * Sync a cache to backing disk.
385 static void cachefiles_sync_cache(struct cachefiles_cache *cache)  in cachefiles_sync_cache()  argument
390 	_enter("%s", cache->cache->name);  in cachefiles_sync_cache()
394 	cachefiles_begin_secure(cache, &saved_cred);  in cachefiles_sync_cache()
395 	down_read(&cache->mnt->mnt_sb->s_umount);  in cachefiles_sync_cache()
396 	ret = sync_filesystem(cache->mnt->mnt_sb);  in cachefiles_sync_cache()
397 	up_read(&cache->mnt->mnt_sb->s_umount);  in cachefiles_sync_cache()
398 	cachefiles_end_secure(cache, saved_cred);  in cachefiles_sync_cache()
401 		cachefiles_io_error(cache,  in cachefiles_sync_cache()
407  * Withdraw cache objects.
409 void cachefiles_withdraw_cache(struct cachefiles_cache *cache)  in cachefiles_withdraw_cache()  argument
411 	struct fscache_cache *fscache = cache->cache;  in cachefiles_withdraw_cache()
413 	pr_info("File cache on %s unregistering\n", fscache->name);  in cachefiles_withdraw_cache()
416 	cachefiles_withdraw_fscache_volumes(cache);  in cachefiles_withdraw_cache()
419 	 * cache - which we do by passing them off to thread pool to be  in cachefiles_withdraw_cache()
421 	cachefiles_withdraw_objects(cache);  in cachefiles_withdraw_cache()
424 	cachefiles_withdraw_volumes(cache);  in cachefiles_withdraw_cache()
425 	cachefiles_sync_cache(cache);  in cachefiles_withdraw_cache()
426 	cache->cache = NULL;  in cachefiles_withdraw_cache()