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
18struct btrfs_chunk_map;
19struct btrfs_fs_info;
20struct btrfs_inode;
21struct btrfs_trans_handle;
22
23enum btrfs_disk_cache_state {
24 BTRFS_DC_WRITTEN,
25 BTRFS_DC_ERROR,
26 BTRFS_DC_CLEAR,
27 BTRFS_DC_SETUP,
28};
29
30enum 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 */
48enum 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 activates the zone
67 */
68enum 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 */
76enum 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
97enum btrfs_caching_type {
98 BTRFS_CACHE_NO,
99 BTRFS_CACHE_STARTED,
100 BTRFS_CACHE_FINISHED,
101 BTRFS_CACHE_ERROR,
102};
103
104struct 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
118struct 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 /* Protected by @free_space_lock. */
250 bool using_free_space_bitmaps;
251 /* Protected by @free_space_lock. */
252 bool using_free_space_bitmaps_cached;
253
254 /*
255 * Number of extents in this block group used for swap files.
256 * All accesses protected by the spinlock 'lock'.
257 */
258 int swap_extents;
259
260 /*
261 * Allocation offset for the block group to implement sequential
262 * allocation. This is used only on a zoned filesystem.
263 */
264 u64 alloc_offset;
265 u64 zone_unusable;
266 u64 zone_capacity;
267 u64 meta_write_pointer;
268 struct btrfs_chunk_map *physical_map;
269 struct list_head active_bg_list;
270 struct work_struct zone_finish_work;
271 struct extent_buffer *last_eb;
272 enum btrfs_block_group_size_class size_class;
273 u64 reclaim_mark;
274};
275
276static inline u64 btrfs_block_group_end(const struct btrfs_block_group *block_group)
277{
278 return (block_group->start + block_group->length);
279}
280
281static inline bool btrfs_is_block_group_used(const struct btrfs_block_group *bg)
282{
283 lockdep_assert_held(&bg->lock);
284
285 return (bg->used > 0 || bg->reserved > 0 || bg->pinned > 0);
286}
287
288static inline bool btrfs_is_block_group_data_only(const struct btrfs_block_group *block_group)
289{
290 /*
291 * In mixed mode the fragmentation is expected to be high, lowering the
292 * efficiency, so only proper data block groups are considered.
293 */
294 return (block_group->flags & BTRFS_BLOCK_GROUP_DATA) &&
295 !(block_group->flags & BTRFS_BLOCK_GROUP_METADATA);
296}
297
298#ifdef CONFIG_BTRFS_DEBUG
299int btrfs_should_fragment_free_space(const struct btrfs_block_group *block_group);
300#endif
301
302struct btrfs_block_group *btrfs_lookup_first_block_group(
303 struct btrfs_fs_info *info, u64 bytenr);
304struct btrfs_block_group *btrfs_lookup_block_group(
305 struct btrfs_fs_info *info, u64 bytenr);
306struct btrfs_block_group *btrfs_next_block_group(
307 struct btrfs_block_group *cache);
308void btrfs_get_block_group(struct btrfs_block_group *cache);
309void btrfs_put_block_group(struct btrfs_block_group *cache);
310void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
311 const u64 start);
312void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg);
313struct btrfs_block_group *btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info,
314 u64 bytenr);
315void btrfs_dec_nocow_writers(struct btrfs_block_group *bg);
316void btrfs_wait_nocow_writers(struct btrfs_block_group *bg);
317void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache,
318 u64 num_bytes);
319int btrfs_cache_block_group(struct btrfs_block_group *cache, bool wait);
320struct btrfs_caching_control *btrfs_get_caching_control(
321 struct btrfs_block_group *cache);
322int btrfs_add_new_free_space(struct btrfs_block_group *block_group,
323 u64 start, u64 end, u64 *total_added_ret);
324struct btrfs_trans_handle *btrfs_start_trans_remove_block_group(
325 struct btrfs_fs_info *fs_info,
326 const u64 chunk_offset);
327int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
328 struct btrfs_chunk_map *map);
329void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info);
330void btrfs_mark_bg_unused(struct btrfs_block_group *bg);
331void btrfs_reclaim_bgs_work(struct work_struct *work);
332void btrfs_reclaim_bgs(struct btrfs_fs_info *fs_info);
333void btrfs_mark_bg_to_reclaim(struct btrfs_block_group *bg);
334int btrfs_read_block_groups(struct btrfs_fs_info *info);
335struct btrfs_block_group *btrfs_make_block_group(struct btrfs_trans_handle *trans,
336 struct btrfs_space_info *space_info,
337 u64 type, u64 chunk_offset, u64 size);
338void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans);
339int btrfs_inc_block_group_ro(struct btrfs_block_group *cache,
340 bool do_chunk_alloc);
341void btrfs_dec_block_group_ro(struct btrfs_block_group *cache);
342int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans);
343int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans);
344int btrfs_setup_space_cache(struct btrfs_trans_handle *trans);
345int btrfs_update_block_group(struct btrfs_trans_handle *trans,
346 u64 bytenr, u64 num_bytes, bool alloc);
347int btrfs_add_reserved_bytes(struct btrfs_block_group *cache,
348 u64 ram_bytes, u64 num_bytes, bool delalloc,
349 bool force_wrong_size_class);
350void btrfs_free_reserved_bytes(struct btrfs_block_group *cache, u64 num_bytes,
351 bool is_delalloc);
352int btrfs_chunk_alloc(struct btrfs_trans_handle *trans,
353 struct btrfs_space_info *space_info, u64 flags,
354 enum btrfs_chunk_alloc_enum force);
355int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type);
356void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type);
357void btrfs_reserve_chunk_metadata(struct btrfs_trans_handle *trans,
358 bool is_item_insertion);
359u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags);
360void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
361int btrfs_free_block_groups(struct btrfs_fs_info *info);
362int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
363 u64 physical, u64 **logical, int *naddrs, int *stripe_len);
364
365static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
366{
367 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA);
368}
369
370static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info)
371{
372 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA);
373}
374
375static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
376{
377 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
378}
379
380static inline int btrfs_block_group_done(const struct btrfs_block_group *cache)
381{
382 smp_mb();
383 return cache->cached == BTRFS_CACHE_FINISHED ||
384 cache->cached == BTRFS_CACHE_ERROR;
385}
386
387void btrfs_freeze_block_group(struct btrfs_block_group *cache);
388void btrfs_unfreeze_block_group(struct btrfs_block_group *cache);
389
390bool btrfs_inc_block_group_swap_extents(struct btrfs_block_group *bg);
391void btrfs_dec_block_group_swap_extents(struct btrfs_block_group *bg, int amount);
392
393enum btrfs_block_group_size_class btrfs_calc_block_group_size_class(u64 size);
394int btrfs_use_block_group_size_class(struct btrfs_block_group *bg,
395 enum btrfs_block_group_size_class size_class,
396 bool force_wrong_size_class);
397bool btrfs_block_group_should_use_size_class(const struct btrfs_block_group *bg);
398
399#endif /* BTRFS_BLOCK_GROUP_H */
400

source code of linux/fs/btrfs/block-group.h