xref: /openbmc/linux/fs/btrfs/space-info.c (revision 5da6afeb)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include "ctree.h"
4 #include "space-info.h"
5 #include "sysfs.h"
6 #include "volumes.h"
7 #include "free-space-cache.h"
8 
9 u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
10 			  bool may_use_included)
11 {
12 	ASSERT(s_info);
13 	return s_info->bytes_used + s_info->bytes_reserved +
14 		s_info->bytes_pinned + s_info->bytes_readonly +
15 		(may_use_included ? s_info->bytes_may_use : 0);
16 }
17 
18 /*
19  * after adding space to the filesystem, we need to clear the full flags
20  * on all the space infos.
21  */
22 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
23 {
24 	struct list_head *head = &info->space_info;
25 	struct btrfs_space_info *found;
26 
27 	rcu_read_lock();
28 	list_for_each_entry_rcu(found, head, list)
29 		found->full = 0;
30 	rcu_read_unlock();
31 }
32 
33 static const char *alloc_name(u64 flags)
34 {
35 	switch (flags) {
36 	case BTRFS_BLOCK_GROUP_METADATA|BTRFS_BLOCK_GROUP_DATA:
37 		return "mixed";
38 	case BTRFS_BLOCK_GROUP_METADATA:
39 		return "metadata";
40 	case BTRFS_BLOCK_GROUP_DATA:
41 		return "data";
42 	case BTRFS_BLOCK_GROUP_SYSTEM:
43 		return "system";
44 	default:
45 		WARN_ON(1);
46 		return "invalid-combination";
47 	};
48 }
49 
50 static int create_space_info(struct btrfs_fs_info *info, u64 flags)
51 {
52 
53 	struct btrfs_space_info *space_info;
54 	int i;
55 	int ret;
56 
57 	space_info = kzalloc(sizeof(*space_info), GFP_NOFS);
58 	if (!space_info)
59 		return -ENOMEM;
60 
61 	ret = percpu_counter_init(&space_info->total_bytes_pinned, 0,
62 				 GFP_KERNEL);
63 	if (ret) {
64 		kfree(space_info);
65 		return ret;
66 	}
67 
68 	for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
69 		INIT_LIST_HEAD(&space_info->block_groups[i]);
70 	init_rwsem(&space_info->groups_sem);
71 	spin_lock_init(&space_info->lock);
72 	space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
73 	space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
74 	init_waitqueue_head(&space_info->wait);
75 	INIT_LIST_HEAD(&space_info->ro_bgs);
76 	INIT_LIST_HEAD(&space_info->tickets);
77 	INIT_LIST_HEAD(&space_info->priority_tickets);
78 
79 	ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
80 				    info->space_info_kobj, "%s",
81 				    alloc_name(space_info->flags));
82 	if (ret) {
83 		kobject_put(&space_info->kobj);
84 		return ret;
85 	}
86 
87 	list_add_rcu(&space_info->list, &info->space_info);
88 	if (flags & BTRFS_BLOCK_GROUP_DATA)
89 		info->data_sinfo = space_info;
90 
91 	return ret;
92 }
93 
94 int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
95 {
96 	struct btrfs_super_block *disk_super;
97 	u64 features;
98 	u64 flags;
99 	int mixed = 0;
100 	int ret;
101 
102 	disk_super = fs_info->super_copy;
103 	if (!btrfs_super_root(disk_super))
104 		return -EINVAL;
105 
106 	features = btrfs_super_incompat_flags(disk_super);
107 	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
108 		mixed = 1;
109 
110 	flags = BTRFS_BLOCK_GROUP_SYSTEM;
111 	ret = create_space_info(fs_info, flags);
112 	if (ret)
113 		goto out;
114 
115 	if (mixed) {
116 		flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
117 		ret = create_space_info(fs_info, flags);
118 	} else {
119 		flags = BTRFS_BLOCK_GROUP_METADATA;
120 		ret = create_space_info(fs_info, flags);
121 		if (ret)
122 			goto out;
123 
124 		flags = BTRFS_BLOCK_GROUP_DATA;
125 		ret = create_space_info(fs_info, flags);
126 	}
127 out:
128 	return ret;
129 }
130 
131 void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags,
132 			     u64 total_bytes, u64 bytes_used,
133 			     u64 bytes_readonly,
134 			     struct btrfs_space_info **space_info)
135 {
136 	struct btrfs_space_info *found;
137 	int factor;
138 
139 	factor = btrfs_bg_type_to_factor(flags);
140 
141 	found = btrfs_find_space_info(info, flags);
142 	ASSERT(found);
143 	spin_lock(&found->lock);
144 	found->total_bytes += total_bytes;
145 	found->disk_total += total_bytes * factor;
146 	found->bytes_used += bytes_used;
147 	found->disk_used += bytes_used * factor;
148 	found->bytes_readonly += bytes_readonly;
149 	if (total_bytes > 0)
150 		found->full = 0;
151 	btrfs_space_info_add_new_bytes(info, found,
152 				       total_bytes - bytes_used -
153 				       bytes_readonly);
154 	spin_unlock(&found->lock);
155 	*space_info = found;
156 }
157 
158 struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
159 					       u64 flags)
160 {
161 	struct list_head *head = &info->space_info;
162 	struct btrfs_space_info *found;
163 
164 	flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
165 
166 	rcu_read_lock();
167 	list_for_each_entry_rcu(found, head, list) {
168 		if (found->flags & flags) {
169 			rcu_read_unlock();
170 			return found;
171 		}
172 	}
173 	rcu_read_unlock();
174 	return NULL;
175 }
176 
177 static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
178 {
179 	return (global->size << 1);
180 }
181 
182 int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
183 			 struct btrfs_space_info *space_info, u64 bytes,
184 			 enum btrfs_reserve_flush_enum flush,
185 			 bool system_chunk)
186 {
187 	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
188 	u64 profile;
189 	u64 space_size;
190 	u64 avail;
191 	u64 used;
192 	int factor;
193 
194 	/* Don't overcommit when in mixed mode. */
195 	if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
196 		return 0;
197 
198 	if (system_chunk)
199 		profile = btrfs_system_alloc_profile(fs_info);
200 	else
201 		profile = btrfs_metadata_alloc_profile(fs_info);
202 
203 	used = btrfs_space_info_used(space_info, false);
204 
205 	/*
206 	 * We only want to allow over committing if we have lots of actual space
207 	 * free, but if we don't have enough space to handle the global reserve
208 	 * space then we could end up having a real enospc problem when trying
209 	 * to allocate a chunk or some other such important allocation.
210 	 */
211 	spin_lock(&global_rsv->lock);
212 	space_size = calc_global_rsv_need_space(global_rsv);
213 	spin_unlock(&global_rsv->lock);
214 	if (used + space_size >= space_info->total_bytes)
215 		return 0;
216 
217 	used += space_info->bytes_may_use;
218 
219 	avail = atomic64_read(&fs_info->free_chunk_space);
220 
221 	/*
222 	 * If we have dup, raid1 or raid10 then only half of the free
223 	 * space is actually usable.  For raid56, the space info used
224 	 * doesn't include the parity drive, so we don't have to
225 	 * change the math
226 	 */
227 	factor = btrfs_bg_type_to_factor(profile);
228 	avail = div_u64(avail, factor);
229 
230 	/*
231 	 * If we aren't flushing all things, let us overcommit up to
232 	 * 1/2th of the space. If we can flush, don't let us overcommit
233 	 * too much, let it overcommit up to 1/8 of the space.
234 	 */
235 	if (flush == BTRFS_RESERVE_FLUSH_ALL)
236 		avail >>= 3;
237 	else
238 		avail >>= 1;
239 
240 	if (used + bytes < space_info->total_bytes + avail)
241 		return 1;
242 	return 0;
243 }
244 
245 /*
246  * This is for space we already have accounted in space_info->bytes_may_use, so
247  * basically when we're returning space from block_rsv's.
248  */
249 void btrfs_space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
250 				    struct btrfs_space_info *space_info,
251 				    u64 num_bytes)
252 {
253 	struct reserve_ticket *ticket;
254 	struct list_head *head;
255 	u64 used;
256 	enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH;
257 	bool check_overcommit = false;
258 
259 	spin_lock(&space_info->lock);
260 	head = &space_info->priority_tickets;
261 
262 	/*
263 	 * If we are over our limit then we need to check and see if we can
264 	 * overcommit, and if we can't then we just need to free up our space
265 	 * and not satisfy any requests.
266 	 */
267 	used = btrfs_space_info_used(space_info, true);
268 	if (used - num_bytes >= space_info->total_bytes)
269 		check_overcommit = true;
270 again:
271 	while (!list_empty(head) && num_bytes) {
272 		ticket = list_first_entry(head, struct reserve_ticket,
273 					  list);
274 		/*
275 		 * We use 0 bytes because this space is already reserved, so
276 		 * adding the ticket space would be a double count.
277 		 */
278 		if (check_overcommit &&
279 		    !btrfs_can_overcommit(fs_info, space_info, 0, flush,
280 					  false))
281 			break;
282 		if (num_bytes >= ticket->bytes) {
283 			list_del_init(&ticket->list);
284 			num_bytes -= ticket->bytes;
285 			ticket->bytes = 0;
286 			space_info->tickets_id++;
287 			wake_up(&ticket->wait);
288 		} else {
289 			ticket->bytes -= num_bytes;
290 			num_bytes = 0;
291 		}
292 	}
293 
294 	if (num_bytes && head == &space_info->priority_tickets) {
295 		head = &space_info->tickets;
296 		flush = BTRFS_RESERVE_FLUSH_ALL;
297 		goto again;
298 	}
299 	btrfs_space_info_update_bytes_may_use(fs_info, space_info, -num_bytes);
300 	trace_btrfs_space_reservation(fs_info, "space_info",
301 				      space_info->flags, num_bytes, 0);
302 	spin_unlock(&space_info->lock);
303 }
304 
305 /*
306  * This is for newly allocated space that isn't accounted in
307  * space_info->bytes_may_use yet.  So if we allocate a chunk or unpin an extent
308  * we use this helper.
309  */
310 void btrfs_space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
311 				    struct btrfs_space_info *space_info,
312 				    u64 num_bytes)
313 {
314 	struct reserve_ticket *ticket;
315 	struct list_head *head = &space_info->priority_tickets;
316 
317 again:
318 	while (!list_empty(head) && num_bytes) {
319 		ticket = list_first_entry(head, struct reserve_ticket,
320 					  list);
321 		if (num_bytes >= ticket->bytes) {
322 			trace_btrfs_space_reservation(fs_info, "space_info",
323 						      space_info->flags,
324 						      ticket->bytes, 1);
325 			list_del_init(&ticket->list);
326 			num_bytes -= ticket->bytes;
327 			btrfs_space_info_update_bytes_may_use(fs_info,
328 							      space_info,
329 							      ticket->bytes);
330 			ticket->bytes = 0;
331 			space_info->tickets_id++;
332 			wake_up(&ticket->wait);
333 		} else {
334 			trace_btrfs_space_reservation(fs_info, "space_info",
335 						      space_info->flags,
336 						      num_bytes, 1);
337 			btrfs_space_info_update_bytes_may_use(fs_info,
338 							      space_info,
339 							      num_bytes);
340 			ticket->bytes -= num_bytes;
341 			num_bytes = 0;
342 		}
343 	}
344 
345 	if (num_bytes && head == &space_info->priority_tickets) {
346 		head = &space_info->tickets;
347 		goto again;
348 	}
349 }
350 
351 #define DUMP_BLOCK_RSV(fs_info, rsv_name)				\
352 do {									\
353 	struct btrfs_block_rsv *__rsv = &(fs_info)->rsv_name;		\
354 	spin_lock(&__rsv->lock);					\
355 	btrfs_info(fs_info, #rsv_name ": size %llu reserved %llu",	\
356 		   __rsv->size, __rsv->reserved);			\
357 	spin_unlock(&__rsv->lock);					\
358 } while (0)
359 
360 void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
361 			   struct btrfs_space_info *info, u64 bytes,
362 			   int dump_block_groups)
363 {
364 	struct btrfs_block_group_cache *cache;
365 	int index = 0;
366 
367 	spin_lock(&info->lock);
368 	btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull",
369 		   info->flags,
370 		   info->total_bytes - btrfs_space_info_used(info, true),
371 		   info->full ? "" : "not ");
372 	btrfs_info(fs_info,
373 		"space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
374 		info->total_bytes, info->bytes_used, info->bytes_pinned,
375 		info->bytes_reserved, info->bytes_may_use,
376 		info->bytes_readonly);
377 	spin_unlock(&info->lock);
378 
379 	DUMP_BLOCK_RSV(fs_info, global_block_rsv);
380 	DUMP_BLOCK_RSV(fs_info, trans_block_rsv);
381 	DUMP_BLOCK_RSV(fs_info, chunk_block_rsv);
382 	DUMP_BLOCK_RSV(fs_info, delayed_block_rsv);
383 	DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv);
384 
385 	if (!dump_block_groups)
386 		return;
387 
388 	down_read(&info->groups_sem);
389 again:
390 	list_for_each_entry(cache, &info->block_groups[index], list) {
391 		spin_lock(&cache->lock);
392 		btrfs_info(fs_info,
393 			"block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
394 			cache->key.objectid, cache->key.offset,
395 			btrfs_block_group_used(&cache->item), cache->pinned,
396 			cache->reserved, cache->ro ? "[readonly]" : "");
397 		btrfs_dump_free_space(cache, bytes);
398 		spin_unlock(&cache->lock);
399 	}
400 	if (++index < BTRFS_NR_RAID_TYPES)
401 		goto again;
402 	up_read(&info->groups_sem);
403 }
404