1 /* SPDX-License-Identifier: GPL-2.0 */
3 #ifndef BTRFS_BLOCK_GROUP_H
4 #define BTRFS_BLOCK_GROUP_H
6 #include "free-space-cache.h"
8 enum btrfs_disk_cache_state {
16 * Control flags for do_chunk_alloc's force field CHUNK_ALLOC_NO_FORCE means to
17 * only allocate a chunk if we really need one.
19 * CHUNK_ALLOC_LIMITED means to only try and allocate one if we have very few
20 * chunks already allocated. This is used as part of the clustering code to
21 * help make sure we have a good pool of storage to cluster in, without filling
22 * the FS with empty chunks
24 * CHUNK_ALLOC_FORCE means it must try to allocate one
26 enum btrfs_chunk_alloc_enum {
32 struct btrfs_caching_control {
33 struct list_head list;
35 wait_queue_head_t wait;
36 struct btrfs_work work;
37 struct btrfs_block_group_cache *block_group;
42 /* Once caching_thread() finds this much free space, it will wake up waiters. */
43 #define CACHING_CTL_WAKE_UP SZ_2M
45 struct btrfs_block_group_cache {
47 struct btrfs_block_group_item item;
48 struct btrfs_fs_info *fs_info;
59 * If the free space extent count exceeds this number, convert the block
62 u32 bitmap_high_thresh;
65 * If the free space extent count drops below this number, convert the
66 * block group back to extents.
68 u32 bitmap_low_thresh;
71 * It is just used for the delayed data space allocation because
72 * only the data space allocation and the relative metadata update
73 * can be done cross the transaction.
75 struct rw_semaphore data_rwsem;
77 /* For raid56, this is a full stripe, without parity */
78 unsigned long full_stripe_len;
82 unsigned int has_caching_ctl:1;
83 unsigned int removed:1;
87 /* Cache tracking stuff */
89 struct btrfs_caching_control *caching_ctl;
90 u64 last_byte_to_unpin;
92 struct btrfs_space_info *space_info;
94 /* Free space cache stuff */
95 struct btrfs_free_space_ctl *free_space_ctl;
97 /* Block group cache stuff */
98 struct rb_node cache_node;
100 /* For block groups in the same raid type */
101 struct list_head list;
107 * List of struct btrfs_free_clusters for this block group.
108 * Today it will only have one thing on it, but that may change
110 struct list_head cluster_list;
112 /* For delayed block group creation or deletion of empty block groups */
113 struct list_head bg_list;
115 /* For read-only block groups */
116 struct list_head ro_list;
120 /* For dirty block groups */
121 struct list_head dirty_list;
122 struct list_head io_list;
124 struct btrfs_io_ctl io_ctl;
127 * Incremented when doing extent allocations and holding a read lock
128 * on the space_info's groups_sem semaphore.
129 * Decremented when an ordered extent that represents an IO against this
130 * block group's range is created (after it's added to its inode's
131 * root's list of ordered extents) or immediately after the allocation
132 * if it's a metadata extent or fallocate extent (for these cases we
133 * don't create ordered extents).
135 atomic_t reservations;
138 * Incremented while holding the spinlock *lock* by a task checking if
139 * it can perform a nocow write (incremented if the value for the *ro*
140 * field is 0). Decremented by such tasks once they create an ordered
141 * extent or before that if some error happens before reaching that step.
142 * This is to prevent races between block group relocation and nocow
143 * writes through direct IO.
145 atomic_t nocow_writers;
147 /* Lock for free space tree operations. */
148 struct mutex free_space_lock;
151 * Does the block group need to be added to the free space tree?
152 * Protected by free_space_lock.
154 int needs_free_space;
156 /* Record locked full stripes for RAID5/6 block group */
157 struct btrfs_full_stripe_locks_tree full_stripe_locks_root;
160 #ifdef CONFIG_BTRFS_DEBUG
161 static inline int btrfs_should_fragment_free_space(
162 struct btrfs_block_group_cache *block_group)
164 struct btrfs_fs_info *fs_info = block_group->fs_info;
166 return (btrfs_test_opt(fs_info, FRAGMENT_METADATA) &&
167 block_group->flags & BTRFS_BLOCK_GROUP_METADATA) ||
168 (btrfs_test_opt(fs_info, FRAGMENT_DATA) &&
169 block_group->flags & BTRFS_BLOCK_GROUP_DATA);
173 struct btrfs_block_group_cache *btrfs_lookup_first_block_group(
174 struct btrfs_fs_info *info, u64 bytenr);
175 struct btrfs_block_group_cache *btrfs_lookup_block_group(
176 struct btrfs_fs_info *info, u64 bytenr);
177 struct btrfs_block_group_cache *btrfs_next_block_group(
178 struct btrfs_block_group_cache *cache);
179 void btrfs_get_block_group(struct btrfs_block_group_cache *cache);
180 void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
181 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
183 void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg);
184 bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);
185 void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);
186 void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg);
187 void btrfs_wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
189 int btrfs_wait_block_group_cache_done(struct btrfs_block_group_cache *cache);
190 int btrfs_cache_block_group(struct btrfs_block_group_cache *cache,
191 int load_cache_only);
192 void btrfs_put_caching_control(struct btrfs_caching_control *ctl);
193 struct btrfs_caching_control *btrfs_get_caching_control(
194 struct btrfs_block_group_cache *cache);
195 u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
197 struct btrfs_trans_handle *btrfs_start_trans_remove_block_group(
198 struct btrfs_fs_info *fs_info,
199 const u64 chunk_offset);
200 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
201 u64 group_start, struct extent_map *em);
202 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info);
203 void btrfs_mark_bg_unused(struct btrfs_block_group_cache *bg);
204 int btrfs_read_block_groups(struct btrfs_fs_info *info);
205 int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
206 u64 type, u64 chunk_offset, u64 size);
207 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans);
208 int btrfs_inc_block_group_ro(struct btrfs_block_group_cache *cache);
209 void btrfs_dec_block_group_ro(struct btrfs_block_group_cache *cache);
210 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans);
211 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans);
212 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans);
213 int btrfs_update_block_group(struct btrfs_trans_handle *trans,
214 u64 bytenr, u64 num_bytes, int alloc);
215 int btrfs_add_reserved_bytes(struct btrfs_block_group_cache *cache,
216 u64 ram_bytes, u64 num_bytes, int delalloc);
217 void btrfs_free_reserved_bytes(struct btrfs_block_group_cache *cache,
218 u64 num_bytes, int delalloc);
219 int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
220 enum btrfs_chunk_alloc_enum force);
221 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type);
222 void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type);
223 u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags);
224 void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
225 int btrfs_free_block_groups(struct btrfs_fs_info *info);
227 static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
229 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA);
232 static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info)
234 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA);
237 static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
239 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
242 static inline int btrfs_block_group_cache_done(
243 struct btrfs_block_group_cache *cache)
246 return cache->cached == BTRFS_CACHE_FINISHED ||
247 cache->cached == BTRFS_CACHE_ERROR;
250 #endif /* BTRFS_BLOCK_GROUP_H */