1 /* SPDX-License-Identifier: GPL-2.0 */
2
3 #ifndef BTRFS_BLOCK_GROUP_H
4 #define BTRFS_BLOCK_GROUP_H
5
6 #include "free-space-cache.h"
7
8 enum btrfs_disk_cache_state {
9 BTRFS_DC_WRITTEN,
10 BTRFS_DC_ERROR,
11 BTRFS_DC_CLEAR,
12 BTRFS_DC_SETUP,
13 };
14
15 /*
16 * This describes the state of the block_group for async discard. This is due
17 * to the two pass nature of it where extent discarding is prioritized over
18 * bitmap discarding. BTRFS_DISCARD_RESET_CURSOR is set when we are resetting
19 * between lists to prevent contention for discard state variables
20 * (eg. discard_cursor).
21 */
22 enum btrfs_discard_state {
23 BTRFS_DISCARD_EXTENTS,
24 BTRFS_DISCARD_BITMAPS,
25 BTRFS_DISCARD_RESET_CURSOR,
26 };
27
28 /*
29 * Control flags for do_chunk_alloc's force field CHUNK_ALLOC_NO_FORCE means to
30 * only allocate a chunk if we really need one.
31 *
32 * CHUNK_ALLOC_LIMITED means to only try and allocate one if we have very few
33 * chunks already allocated. This is used as part of the clustering code to
34 * help make sure we have a good pool of storage to cluster in, without filling
35 * the FS with empty chunks
36 *
37 * CHUNK_ALLOC_FORCE means it must try to allocate one
38 */
39 enum btrfs_chunk_alloc_enum {
40 CHUNK_ALLOC_NO_FORCE,
41 CHUNK_ALLOC_LIMITED,
42 CHUNK_ALLOC_FORCE,
43 };
44
45 struct btrfs_caching_control {
46 struct list_head list;
47 struct mutex mutex;
48 wait_queue_head_t wait;
49 struct btrfs_work work;
50 struct btrfs_block_group *block_group;
51 u64 progress;
52 refcount_t count;
53 };
54
55 /* Once caching_thread() finds this much free space, it will wake up waiters. */
56 #define CACHING_CTL_WAKE_UP SZ_2M
57
58 struct btrfs_block_group {
59 struct btrfs_fs_info *fs_info;
60 struct inode *inode;
61 spinlock_t lock;
62 u64 start;
63 u64 length;
64 u64 pinned;
65 u64 reserved;
66 u64 used;
67 u64 delalloc_bytes;
68 u64 bytes_super;
69 u64 flags;
70 u64 cache_generation;
71
72 /*
73 * If the free space extent count exceeds this number, convert the block
74 * group to bitmaps.
75 */
76 u32 bitmap_high_thresh;
77
78 /*
79 * If the free space extent count drops below this number, convert the
80 * block group back to extents.
81 */
82 u32 bitmap_low_thresh;
83
84 /*
85 * It is just used for the delayed data space allocation because
86 * only the data space allocation and the relative metadata update
87 * can be done cross the transaction.
88 */
89 struct rw_semaphore data_rwsem;
90
91 /* For raid56, this is a full stripe, without parity */
92 unsigned long full_stripe_len;
93
94 unsigned int ro;
95 unsigned int iref:1;
96 unsigned int has_caching_ctl:1;
97 unsigned int removed:1;
98 unsigned int to_copy:1;
99 unsigned int relocating_repair:1;
100 unsigned int chunk_item_inserted:1;
101
102 int disk_cache_state;
103
104 /* Cache tracking stuff */
105 int cached;
106 struct btrfs_caching_control *caching_ctl;
107 u64 last_byte_to_unpin;
108
109 struct btrfs_space_info *space_info;
110
111 /* Free space cache stuff */
112 struct btrfs_free_space_ctl *free_space_ctl;
113
114 /* Block group cache stuff */
115 struct rb_node cache_node;
116
117 /* For block groups in the same raid type */
118 struct list_head list;
119
120 refcount_t refs;
121
122 /*
123 * List of struct btrfs_free_clusters for this block group.
124 * Today it will only have one thing on it, but that may change
125 */
126 struct list_head cluster_list;
127
128 /* For delayed block group creation or deletion of empty block groups */
129 struct list_head bg_list;
130
131 /* For read-only block groups */
132 struct list_head ro_list;
133
134 /*
135 * When non-zero it means the block group's logical address and its
136 * device extents can not be reused for future block group allocations
137 * until the counter goes down to 0. This is to prevent them from being
138 * reused while some task is still using the block group after it was
139 * deleted - we want to make sure they can only be reused for new block
140 * groups after that task is done with the deleted block group.
141 */
142 atomic_t frozen;
143
144 /* For discard operations */
145 struct list_head discard_list;
146 int discard_index;
147 u64 discard_eligible_time;
148 u64 discard_cursor;
149 enum btrfs_discard_state discard_state;
150
151 /* For dirty block groups */
152 struct list_head dirty_list;
153 struct list_head io_list;
154
155 struct btrfs_io_ctl io_ctl;
156
157 /*
158 * Incremented when doing extent allocations and holding a read lock
159 * on the space_info's groups_sem semaphore.
160 * Decremented when an ordered extent that represents an IO against this
161 * block group's range is created (after it's added to its inode's
162 * root's list of ordered extents) or immediately after the allocation
163 * if it's a metadata extent or fallocate extent (for these cases we
164 * don't create ordered extents).
165 */
166 atomic_t reservations;
167
168 /*
169 * Incremented while holding the spinlock *lock* by a task checking if
170 * it can perform a nocow write (incremented if the value for the *ro*
171 * field is 0). Decremented by such tasks once they create an ordered
172 * extent or before that if some error happens before reaching that step.
173 * This is to prevent races between block group relocation and nocow
174 * writes through direct IO.
175 */
176 atomic_t nocow_writers;
177
178 /* Lock for free space tree operations. */
179 struct mutex free_space_lock;
180
181 /*
182 * Does the block group need to be added to the free space tree?
183 * Protected by free_space_lock.
184 */
185 int needs_free_space;
186
187 /* Flag indicating this block group is placed on a sequential zone */
188 bool seq_zone;
189
190 /*
191 * Number of extents in this block group used for swap files.
192 * All accesses protected by the spinlock 'lock'.
193 */
194 int swap_extents;
195
196 /* Record locked full stripes for RAID5/6 block group */
197 struct btrfs_full_stripe_locks_tree full_stripe_locks_root;
198
199 /*
200 * Allocation offset for the block group to implement sequential
201 * allocation. This is used only on a zoned filesystem.
202 */
203 u64 alloc_offset;
204 u64 zone_unusable;
205 u64 meta_write_pointer;
206 };
207
btrfs_block_group_end(struct btrfs_block_group * block_group)208 static inline u64 btrfs_block_group_end(struct btrfs_block_group *block_group)
209 {
210 return (block_group->start + block_group->length);
211 }
212
btrfs_is_block_group_data_only(struct btrfs_block_group * block_group)213 static inline bool btrfs_is_block_group_data_only(
214 struct btrfs_block_group *block_group)
215 {
216 /*
217 * In mixed mode the fragmentation is expected to be high, lowering the
218 * efficiency, so only proper data block groups are considered.
219 */
220 return (block_group->flags & BTRFS_BLOCK_GROUP_DATA) &&
221 !(block_group->flags & BTRFS_BLOCK_GROUP_METADATA);
222 }
223
224 #ifdef CONFIG_BTRFS_DEBUG
btrfs_should_fragment_free_space(struct btrfs_block_group * block_group)225 static inline int btrfs_should_fragment_free_space(
226 struct btrfs_block_group *block_group)
227 {
228 struct btrfs_fs_info *fs_info = block_group->fs_info;
229
230 return (btrfs_test_opt(fs_info, FRAGMENT_METADATA) &&
231 block_group->flags & BTRFS_BLOCK_GROUP_METADATA) ||
232 (btrfs_test_opt(fs_info, FRAGMENT_DATA) &&
233 block_group->flags & BTRFS_BLOCK_GROUP_DATA);
234 }
235 #endif
236
237 struct btrfs_block_group *btrfs_lookup_first_block_group(
238 struct btrfs_fs_info *info, u64 bytenr);
239 struct btrfs_block_group *btrfs_lookup_block_group(
240 struct btrfs_fs_info *info, u64 bytenr);
241 struct btrfs_block_group *btrfs_next_block_group(
242 struct btrfs_block_group *cache);
243 void btrfs_get_block_group(struct btrfs_block_group *cache);
244 void btrfs_put_block_group(struct btrfs_block_group *cache);
245 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
246 const u64 start);
247 void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg);
248 bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);
249 void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);
250 void btrfs_wait_nocow_writers(struct btrfs_block_group *bg);
251 void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache,
252 u64 num_bytes);
253 int btrfs_wait_block_group_cache_done(struct btrfs_block_group *cache);
254 int btrfs_cache_block_group(struct btrfs_block_group *cache,
255 int load_cache_only);
256 void btrfs_put_caching_control(struct btrfs_caching_control *ctl);
257 struct btrfs_caching_control *btrfs_get_caching_control(
258 struct btrfs_block_group *cache);
259 u64 add_new_free_space(struct btrfs_block_group *block_group,
260 u64 start, u64 end);
261 struct btrfs_trans_handle *btrfs_start_trans_remove_block_group(
262 struct btrfs_fs_info *fs_info,
263 const u64 chunk_offset);
264 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
265 u64 group_start, struct extent_map *em);
266 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info);
267 void btrfs_mark_bg_unused(struct btrfs_block_group *bg);
268 void btrfs_reclaim_bgs_work(struct work_struct *work);
269 void btrfs_reclaim_bgs(struct btrfs_fs_info *fs_info);
270 void btrfs_mark_bg_to_reclaim(struct btrfs_block_group *bg);
271 int btrfs_read_block_groups(struct btrfs_fs_info *info);
272 struct btrfs_block_group *btrfs_make_block_group(struct btrfs_trans_handle *trans,
273 u64 bytes_used, u64 type,
274 u64 chunk_offset, u64 size);
275 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans);
276 int btrfs_inc_block_group_ro(struct btrfs_block_group *cache,
277 bool do_chunk_alloc);
278 void btrfs_dec_block_group_ro(struct btrfs_block_group *cache);
279 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans);
280 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans);
281 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans);
282 int btrfs_update_block_group(struct btrfs_trans_handle *trans,
283 u64 bytenr, u64 num_bytes, int alloc);
284 int btrfs_add_reserved_bytes(struct btrfs_block_group *cache,
285 u64 ram_bytes, u64 num_bytes, int delalloc);
286 void btrfs_free_reserved_bytes(struct btrfs_block_group *cache,
287 u64 num_bytes, int delalloc);
288 int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
289 enum btrfs_chunk_alloc_enum force);
290 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type);
291 void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type);
292 u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags);
293 void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
294 int btrfs_free_block_groups(struct btrfs_fs_info *info);
295 void btrfs_wait_space_cache_v1_finished(struct btrfs_block_group *cache,
296 struct btrfs_caching_control *caching_ctl);
297 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
298 struct block_device *bdev, u64 physical, u64 **logical,
299 int *naddrs, int *stripe_len);
300
btrfs_data_alloc_profile(struct btrfs_fs_info * fs_info)301 static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
302 {
303 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA);
304 }
305
btrfs_metadata_alloc_profile(struct btrfs_fs_info * fs_info)306 static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info)
307 {
308 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA);
309 }
310
btrfs_system_alloc_profile(struct btrfs_fs_info * fs_info)311 static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
312 {
313 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
314 }
315
btrfs_block_group_done(struct btrfs_block_group * cache)316 static inline int btrfs_block_group_done(struct btrfs_block_group *cache)
317 {
318 smp_mb();
319 return cache->cached == BTRFS_CACHE_FINISHED ||
320 cache->cached == BTRFS_CACHE_ERROR;
321 }
322
323 void btrfs_freeze_block_group(struct btrfs_block_group *cache);
324 void btrfs_unfreeze_block_group(struct btrfs_block_group *cache);
325
326 bool btrfs_inc_block_group_swap_extents(struct btrfs_block_group *bg);
327 void btrfs_dec_block_group_swap_extents(struct btrfs_block_group *bg, int amount);
328
329 #endif /* BTRFS_BLOCK_GROUP_H */
330
