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
  8enum btrfs_disk_cache_state {
  9	BTRFS_DC_WRITTEN,
 10	BTRFS_DC_ERROR,
 11	BTRFS_DC_CLEAR,
 12	BTRFS_DC_SETUP,
 13};
 14
 15/*
 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.
 18 *
 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
 23 *
 24 * CHUNK_ALLOC_FORCE means it must try to allocate one
 25 */
 26enum btrfs_chunk_alloc_enum {
 27	CHUNK_ALLOC_NO_FORCE,
 28	CHUNK_ALLOC_LIMITED,
 29	CHUNK_ALLOC_FORCE,
 30};
 31
 32struct btrfs_caching_control {
 33	struct list_head list;
 34	struct mutex mutex;
 35	wait_queue_head_t wait;
 36	struct btrfs_work work;
 37	struct btrfs_block_group_cache *block_group;
 38	u64 progress;
 39	refcount_t count;
 40};
 41
 42/* Once caching_thread() finds this much free space, it will wake up waiters. */
 43#define CACHING_CTL_WAKE_UP SZ_2M
 44
 45struct btrfs_block_group_cache {
 46	struct btrfs_key key;
 47	struct btrfs_block_group_item item;
 48	struct btrfs_fs_info *fs_info;
 49	struct inode *inode;
 50	spinlock_t lock;
 51	u64 pinned;
 52	u64 reserved;
 53	u64 delalloc_bytes;
 54	u64 bytes_super;
 55	u64 flags;
 56	u64 cache_generation;
 57
 58	/*
 59	 * If the free space extent count exceeds this number, convert the block
 60	 * group to bitmaps.
 61	 */
 62	u32 bitmap_high_thresh;
 63
 64	/*
 65	 * If the free space extent count drops below this number, convert the
 66	 * block group back to extents.
 67	 */
 68	u32 bitmap_low_thresh;
 69
 70	/*
 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.
 74	 */
 75	struct rw_semaphore data_rwsem;
 76
 77	/* For raid56, this is a full stripe, without parity */
 78	unsigned long full_stripe_len;
 79
 80	unsigned int ro;
 81	unsigned int iref:1;
 82	unsigned int has_caching_ctl:1;
 83	unsigned int removed:1;
 84
 85	int disk_cache_state;
 86
 87	/* Cache tracking stuff */
 88	int cached;
 89	struct btrfs_caching_control *caching_ctl;
 90	u64 last_byte_to_unpin;
 91
 92	struct btrfs_space_info *space_info;
 93
 94	/* Free space cache stuff */
 95	struct btrfs_free_space_ctl *free_space_ctl;
 96
 97	/* Block group cache stuff */
 98	struct rb_node cache_node;
 99
100	/* For block groups in the same raid type */
101	struct list_head list;
102
103	/* Usage count */
104	atomic_t count;
105
106	/*
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
109	 */
110	struct list_head cluster_list;
111
112	/* For delayed block group creation or deletion of empty block groups */
113	struct list_head bg_list;
114
115	/* For read-only block groups */
116	struct list_head ro_list;
117
118	atomic_t trimming;
119
120	/* For dirty block groups */
121	struct list_head dirty_list;
122	struct list_head io_list;
123
124	struct btrfs_io_ctl io_ctl;
125
126	/*
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).
134	 */
135	atomic_t reservations;
136
137	/*
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.
144	 */
145	atomic_t nocow_writers;
146
147	/* Lock for free space tree operations. */
148	struct mutex free_space_lock;
149
150	/*
151	 * Does the block group need to be added to the free space tree?
152	 * Protected by free_space_lock.
153	 */
154	int needs_free_space;
155
156	/* Record locked full stripes for RAID5/6 block group */
157	struct btrfs_full_stripe_locks_tree full_stripe_locks_root;
158};
159
160#ifdef CONFIG_BTRFS_DEBUG
161static inline int btrfs_should_fragment_free_space(
162		struct btrfs_block_group_cache *block_group)
163{
164	struct btrfs_fs_info *fs_info = block_group->fs_info;
165
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);
170}
171#endif
172
173struct btrfs_block_group_cache *btrfs_lookup_first_block_group(
174		struct btrfs_fs_info *info, u64 bytenr);
175struct btrfs_block_group_cache *btrfs_lookup_block_group(
176		struct btrfs_fs_info *info, u64 bytenr);
177struct btrfs_block_group_cache *btrfs_next_block_group(
178		struct btrfs_block_group_cache *cache);
179void btrfs_get_block_group(struct btrfs_block_group_cache *cache);
180void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
181void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
182					const u64 start);
183void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg);
184bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);
185void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);
186void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg);
187void btrfs_wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
188				           u64 num_bytes);
189int btrfs_wait_block_group_cache_done(struct btrfs_block_group_cache *cache);
190int btrfs_cache_block_group(struct btrfs_block_group_cache *cache,
191			    int load_cache_only);
192void btrfs_put_caching_control(struct btrfs_caching_control *ctl);
193struct btrfs_caching_control *btrfs_get_caching_control(
194		struct btrfs_block_group_cache *cache);
195u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
196		       u64 start, u64 end);
197struct btrfs_trans_handle *btrfs_start_trans_remove_block_group(
198				struct btrfs_fs_info *fs_info,
199				const u64 chunk_offset);
200int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
201			     u64 group_start, struct extent_map *em);
202void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info);
203void btrfs_mark_bg_unused(struct btrfs_block_group_cache *bg);
204int btrfs_read_block_groups(struct btrfs_fs_info *info);
205int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
206			   u64 type, u64 chunk_offset, u64 size);
207void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans);
208int btrfs_inc_block_group_ro(struct btrfs_block_group_cache *cache);
209void btrfs_dec_block_group_ro(struct btrfs_block_group_cache *cache);
210int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans);
211int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans);
212int btrfs_setup_space_cache(struct btrfs_trans_handle *trans);
213int btrfs_update_block_group(struct btrfs_trans_handle *trans,
214			     u64 bytenr, u64 num_bytes, int alloc);
215int btrfs_add_reserved_bytes(struct btrfs_block_group_cache *cache,
216			     u64 ram_bytes, u64 num_bytes, int delalloc);
217void btrfs_free_reserved_bytes(struct btrfs_block_group_cache *cache,
218			       u64 num_bytes, int delalloc);
219int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
220		      enum btrfs_chunk_alloc_enum force);
221int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type);
222void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type);
223u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags);
224void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
225int btrfs_free_block_groups(struct btrfs_fs_info *info);
226
227static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
228{
229	return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA);
230}
231
232static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info)
233{
234	return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA);
235}
236
237static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
238{
239	return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
240}
241
242static inline int btrfs_block_group_cache_done(
243		struct btrfs_block_group_cache *cache)
244{
245	smp_mb();
246	return cache->cached == BTRFS_CACHE_FINISHED ||
247		cache->cached == BTRFS_CACHE_ERROR;
248}
249
250#endif /* BTRFS_BLOCK_GROUP_H */