1 /* SPDX-License-Identifier: GPL-2.0 */
2
3 #ifndef BTRFS_BLOCK_GROUP_H
4 #define BTRFS_BLOCK_GROUP_H
5
6 #include <linux/atomic.h>
7 #include <linux/mutex.h>
8 #include <linux/list.h>
9 #include <linux/spinlock.h>
10 #include <linux/refcount.h>
11 #include <linux/wait.h>
12 #include <linux/sizes.h>
13 #include <linux/rwsem.h>
14 #include <linux/rbtree.h>
15 #include <uapi/linux/btrfs_tree.h>
16 #include "free-space-cache.h"
17
18 struct btrfs_chunk_map;
19 struct btrfs_fs_info;
20 struct btrfs_inode;
21 struct btrfs_trans_handle;
22
23 enum btrfs_disk_cache_state {
24 BTRFS_DC_WRITTEN,
25 BTRFS_DC_ERROR,
26 BTRFS_DC_CLEAR,
27 BTRFS_DC_SETUP,
28 };
29
30 enum btrfs_block_group_size_class {
31 /* Unset */
32 BTRFS_BG_SZ_NONE,
33 /* 0 < size <= 128K */
34 BTRFS_BG_SZ_SMALL,
35 /* 128K < size <= 8M */
36 BTRFS_BG_SZ_MEDIUM,
37 /* 8M < size < BG_LENGTH */
38 BTRFS_BG_SZ_LARGE,
39 };
40
41 /*
42 * This describes the state of the block_group for async discard. This is due
43 * to the two pass nature of it where extent discarding is prioritized over
44 * bitmap discarding. BTRFS_DISCARD_RESET_CURSOR is set when we are resetting
45 * between lists to prevent contention for discard state variables
46 * (eg. discard_cursor).
47 */
48 enum btrfs_discard_state {
49 BTRFS_DISCARD_EXTENTS,
50 BTRFS_DISCARD_BITMAPS,
51 BTRFS_DISCARD_RESET_CURSOR,
52 };
53
54 /*
55 * Control flags for do_chunk_alloc's force field CHUNK_ALLOC_NO_FORCE means to
56 * only allocate a chunk if we really need one.
57 *
58 * CHUNK_ALLOC_LIMITED means to only try and allocate one if we have very few
59 * chunks already allocated. This is used as part of the clustering code to
60 * help make sure we have a good pool of storage to cluster in, without filling
61 * the FS with empty chunks
62 *
63 * CHUNK_ALLOC_FORCE means it must try to allocate one
64 *
65 * CHUNK_ALLOC_FORCE_FOR_EXTENT like CHUNK_ALLOC_FORCE but called from
66 * find_free_extent() that also activaes the zone
67 */
68 enum btrfs_chunk_alloc_enum {
69 CHUNK_ALLOC_NO_FORCE,
70 CHUNK_ALLOC_LIMITED,
71 CHUNK_ALLOC_FORCE,
72 CHUNK_ALLOC_FORCE_FOR_EXTENT,
73 };
74
75 /* Block group flags set at runtime */
76 enum btrfs_block_group_flags {
77 BLOCK_GROUP_FLAG_IREF,
78 BLOCK_GROUP_FLAG_REMOVED,
79 BLOCK_GROUP_FLAG_TO_COPY,
80 BLOCK_GROUP_FLAG_RELOCATING_REPAIR,
81 BLOCK_GROUP_FLAG_CHUNK_ITEM_INSERTED,
82 BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE,
83 BLOCK_GROUP_FLAG_ZONED_DATA_RELOC,
84 /* Does the block group need to be added to the free space tree? */
85 BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE,
86 /* Set after we add a new block group to the free space tree. */
87 BLOCK_GROUP_FLAG_FREE_SPACE_ADDED,
88 /* Indicate that the block group is placed on a sequential zone */
89 BLOCK_GROUP_FLAG_SEQUENTIAL_ZONE,
90 /*
91 * Indicate that block group is in the list of new block groups of a
92 * transaction.
93 */
94 BLOCK_GROUP_FLAG_NEW,
95 };
96
97 enum btrfs_caching_type {
98 BTRFS_CACHE_NO,
99 BTRFS_CACHE_STARTED,
100 BTRFS_CACHE_FINISHED,
101 BTRFS_CACHE_ERROR,
102 };
103
104 struct btrfs_caching_control {
105 struct list_head list;
106 struct mutex mutex;
107 wait_queue_head_t wait;
108 struct btrfs_work work;
109 struct btrfs_block_group *block_group;
110 /* Track progress of caching during allocation. */
111 atomic_t progress;
112 refcount_t count;
113 };
114
115 /* Once caching_thread() finds this much free space, it will wake up waiters. */
116 #define CACHING_CTL_WAKE_UP SZ_2M
117
118 struct btrfs_block_group {
119 struct btrfs_fs_info *fs_info;
120 struct btrfs_inode *inode;
121 spinlock_t lock;
122 u64 start;
123 u64 length;
124 u64 pinned;
125 u64 reserved;
126 u64 used;
127 u64 delalloc_bytes;
128 u64 bytes_super;
129 u64 flags;
130 u64 cache_generation;
131 u64 global_root_id;
132
133 /*
134 * The last committed used bytes of this block group, if the above @used
135 * is still the same as @commit_used, we don't need to update block
136 * group item of this block group.
137 */
138 u64 commit_used;
139 /*
140 * If the free space extent count exceeds this number, convert the block
141 * group to bitmaps.
142 */
143 u32 bitmap_high_thresh;
144
145 /*
146 * If the free space extent count drops below this number, convert the
147 * block group back to extents.
148 */
149 u32 bitmap_low_thresh;
150
151 /*
152 * It is just used for the delayed data space allocation because
153 * only the data space allocation and the relative metadata update
154 * can be done cross the transaction.
155 */
156 struct rw_semaphore data_rwsem;
157
158 /* For raid56, this is a full stripe, without parity */
159 unsigned long full_stripe_len;
160 unsigned long runtime_flags;
161
162 unsigned int ro;
163
164 int disk_cache_state;
165
166 /* Cache tracking stuff */
167 int cached;
168 struct btrfs_caching_control *caching_ctl;
169
170 struct btrfs_space_info *space_info;
171
172 /* Free space cache stuff */
173 struct btrfs_free_space_ctl *free_space_ctl;
174
175 /* Block group cache stuff */
176 struct rb_node cache_node;
177
178 /* For block groups in the same raid type */
179 struct list_head list;
180
181 refcount_t refs;
182
183 /*
184 * List of struct btrfs_free_clusters for this block group.
185 * Today it will only have one thing on it, but that may change
186 */
187 struct list_head cluster_list;
188
189 /*
190 * Used for several lists:
191 *
192 * 1) struct btrfs_fs_info::unused_bgs
193 * 2) struct btrfs_fs_info::reclaim_bgs
194 * 3) struct btrfs_transaction::deleted_bgs
195 * 4) struct btrfs_trans_handle::new_bgs
196 */
197 struct list_head bg_list;
198
199 /* For read-only block groups */
200 struct list_head ro_list;
201
202 /*
203 * When non-zero it means the block group's logical address and its
204 * device extents can not be reused for future block group allocations
205 * until the counter goes down to 0. This is to prevent them from being
206 * reused while some task is still using the block group after it was
207 * deleted - we want to make sure they can only be reused for new block
208 * groups after that task is done with the deleted block group.
209 */
210 atomic_t frozen;
211
212 /* For discard operations */
213 struct list_head discard_list;
214 int discard_index;
215 u64 discard_eligible_time;
216 u64 discard_cursor;
217 enum btrfs_discard_state discard_state;
218
219 /* For dirty block groups */
220 struct list_head dirty_list;
221 struct list_head io_list;
222
223 struct btrfs_io_ctl io_ctl;
224
225 /*
226 * Incremented when doing extent allocations and holding a read lock
227 * on the space_info's groups_sem semaphore.
228 * Decremented when an ordered extent that represents an IO against this
229 * block group's range is created (after it's added to its inode's
230 * root's list of ordered extents) or immediately after the allocation
231 * if it's a metadata extent or fallocate extent (for these cases we
232 * don't create ordered extents).
233 */
234 atomic_t reservations;
235
236 /*
237 * Incremented while holding the spinlock *lock* by a task checking if
238 * it can perform a nocow write (incremented if the value for the *ro*
239 * field is 0). Decremented by such tasks once they create an ordered
240 * extent or before that if some error happens before reaching that step.
241 * This is to prevent races between block group relocation and nocow
242 * writes through direct IO.
243 */
244 atomic_t nocow_writers;
245
246 /* Lock for free space tree operations. */
247 struct mutex free_space_lock;
248
249 /*
250 * Number of extents in this block group used for swap files.
251 * All accesses protected by the spinlock 'lock'.
252 */
253 int swap_extents;
254
255 /*
256 * Allocation offset for the block group to implement sequential
257 * allocation. This is used only on a zoned filesystem.
258 */
259 u64 alloc_offset;
260 u64 zone_unusable;
261 u64 zone_capacity;
262 u64 meta_write_pointer;
263 struct btrfs_chunk_map *physical_map;
264 struct list_head active_bg_list;
265 struct work_struct zone_finish_work;
266 struct extent_buffer *last_eb;
267 enum btrfs_block_group_size_class size_class;
268 u64 reclaim_mark;
269 };
270
btrfs_block_group_end(const struct btrfs_block_group * block_group)271 static inline u64 btrfs_block_group_end(const struct btrfs_block_group *block_group)
272 {
273 return (block_group->start + block_group->length);
274 }
275
btrfs_is_block_group_used(const struct btrfs_block_group * bg)276 static inline bool btrfs_is_block_group_used(const struct btrfs_block_group *bg)
277 {
278 lockdep_assert_held(&bg->lock);
279
280 return (bg->used > 0 || bg->reserved > 0 || bg->pinned > 0);
281 }
282
btrfs_is_block_group_data_only(const struct btrfs_block_group * block_group)283 static inline bool btrfs_is_block_group_data_only(const struct btrfs_block_group *block_group)
284 {
285 /*
286 * In mixed mode the fragmentation is expected to be high, lowering the
287 * efficiency, so only proper data block groups are considered.
288 */
289 return (block_group->flags & BTRFS_BLOCK_GROUP_DATA) &&
290 !(block_group->flags & BTRFS_BLOCK_GROUP_METADATA);
291 }
292
293 #ifdef CONFIG_BTRFS_DEBUG
294 int btrfs_should_fragment_free_space(const struct btrfs_block_group *block_group);
295 #endif
296
297 struct btrfs_block_group *btrfs_lookup_first_block_group(
298 struct btrfs_fs_info *info, u64 bytenr);
299 struct btrfs_block_group *btrfs_lookup_block_group(
300 struct btrfs_fs_info *info, u64 bytenr);
301 struct btrfs_block_group *btrfs_next_block_group(
302 struct btrfs_block_group *cache);
303 void btrfs_get_block_group(struct btrfs_block_group *cache);
304 void btrfs_put_block_group(struct btrfs_block_group *cache);
305 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
306 const u64 start);
307 void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg);
308 struct btrfs_block_group *btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info,
309 u64 bytenr);
310 void btrfs_dec_nocow_writers(struct btrfs_block_group *bg);
311 void btrfs_wait_nocow_writers(struct btrfs_block_group *bg);
312 void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache,
313 u64 num_bytes);
314 int btrfs_cache_block_group(struct btrfs_block_group *cache, bool wait);
315 struct btrfs_caching_control *btrfs_get_caching_control(
316 struct btrfs_block_group *cache);
317 int btrfs_add_new_free_space(struct btrfs_block_group *block_group,
318 u64 start, u64 end, u64 *total_added_ret);
319 struct btrfs_trans_handle *btrfs_start_trans_remove_block_group(
320 struct btrfs_fs_info *fs_info,
321 const u64 chunk_offset);
322 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
323 struct btrfs_chunk_map *map);
324 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info);
325 void btrfs_mark_bg_unused(struct btrfs_block_group *bg);
326 void btrfs_reclaim_bgs_work(struct work_struct *work);
327 void btrfs_reclaim_bgs(struct btrfs_fs_info *fs_info);
328 void btrfs_mark_bg_to_reclaim(struct btrfs_block_group *bg);
329 int btrfs_read_block_groups(struct btrfs_fs_info *info);
330 struct btrfs_block_group *btrfs_make_block_group(struct btrfs_trans_handle *trans,
331 struct btrfs_space_info *space_info,
332 u64 type, u64 chunk_offset, u64 size);
333 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans);
334 int btrfs_inc_block_group_ro(struct btrfs_block_group *cache,
335 bool do_chunk_alloc);
336 void btrfs_dec_block_group_ro(struct btrfs_block_group *cache);
337 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans);
338 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans);
339 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans);
340 int btrfs_update_block_group(struct btrfs_trans_handle *trans,
341 u64 bytenr, u64 num_bytes, bool alloc);
342 int btrfs_add_reserved_bytes(struct btrfs_block_group *cache,
343 u64 ram_bytes, u64 num_bytes, int delalloc,
344 bool force_wrong_size_class);
345 void btrfs_free_reserved_bytes(struct btrfs_block_group *cache, u64 num_bytes,
346 bool is_delalloc);
347 int btrfs_chunk_alloc(struct btrfs_trans_handle *trans,
348 struct btrfs_space_info *space_info, u64 flags,
349 enum btrfs_chunk_alloc_enum force);
350 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type);
351 void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type);
352 void btrfs_reserve_chunk_metadata(struct btrfs_trans_handle *trans,
353 bool is_item_insertion);
354 u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags);
355 void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
356 int btrfs_free_block_groups(struct btrfs_fs_info *info);
357 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
358 u64 physical, u64 **logical, int *naddrs, int *stripe_len);
359
btrfs_data_alloc_profile(struct btrfs_fs_info * fs_info)360 static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
361 {
362 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA);
363 }
364
btrfs_metadata_alloc_profile(struct btrfs_fs_info * fs_info)365 static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info)
366 {
367 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA);
368 }
369
btrfs_system_alloc_profile(struct btrfs_fs_info * fs_info)370 static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
371 {
372 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
373 }
374
btrfs_block_group_done(const struct btrfs_block_group * cache)375 static inline int btrfs_block_group_done(const struct btrfs_block_group *cache)
376 {
377 smp_mb();
378 return cache->cached == BTRFS_CACHE_FINISHED ||
379 cache->cached == BTRFS_CACHE_ERROR;
380 }
381
382 void btrfs_freeze_block_group(struct btrfs_block_group *cache);
383 void btrfs_unfreeze_block_group(struct btrfs_block_group *cache);
384
385 bool btrfs_inc_block_group_swap_extents(struct btrfs_block_group *bg);
386 void btrfs_dec_block_group_swap_extents(struct btrfs_block_group *bg, int amount);
387
388 enum btrfs_block_group_size_class btrfs_calc_block_group_size_class(u64 size);
389 int btrfs_use_block_group_size_class(struct btrfs_block_group *bg,
390 enum btrfs_block_group_size_class size_class,
391 bool force_wrong_size_class);
392 bool btrfs_block_group_should_use_size_class(const struct btrfs_block_group *bg);
393
394 #endif /* BTRFS_BLOCK_GROUP_H */
395