xref: /linux/fs/bcachefs/buckets.h (revision 3d0fe49454652117522f60bfbefb978ba0e5300b)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Code for manipulating bucket marks for garbage collection.
4  *
5  * Copyright 2014 Datera, Inc.
6  */
7 
8 #ifndef _BUCKETS_H
9 #define _BUCKETS_H
10 
11 #include "buckets_types.h"
12 #include "extents.h"
13 #include "sb-members.h"
14 
15 static inline size_t sector_to_bucket(const struct bch_dev *ca, sector_t s)
16 {
17 	return div_u64(s, ca->mi.bucket_size);
18 }
19 
20 static inline sector_t bucket_to_sector(const struct bch_dev *ca, size_t b)
21 {
22 	return ((sector_t) b) * ca->mi.bucket_size;
23 }
24 
25 static inline sector_t bucket_remainder(const struct bch_dev *ca, sector_t s)
26 {
27 	u32 remainder;
28 
29 	div_u64_rem(s, ca->mi.bucket_size, &remainder);
30 	return remainder;
31 }
32 
33 static inline size_t sector_to_bucket_and_offset(const struct bch_dev *ca, sector_t s,
34 						 u32 *offset)
35 {
36 	return div_u64_rem(s, ca->mi.bucket_size, offset);
37 }
38 
39 #define for_each_bucket(_b, _buckets)				\
40 	for (_b = (_buckets)->b + (_buckets)->first_bucket;	\
41 	     _b < (_buckets)->b + (_buckets)->nbuckets; _b++)
42 
43 /*
44  * Ugly hack alert:
45  *
46  * We need to cram a spinlock in a single byte, because that's what we have left
47  * in struct bucket, and we care about the size of these - during fsck, we need
48  * in memory state for every single bucket on every device.
49  *
50  * We used to do
51  *   while (xchg(&b->lock, 1) cpu_relax();
52  * but, it turns out not all architectures support xchg on a single byte.
53  *
54  * So now we use bit_spin_lock(), with fun games since we can't burn a whole
55  * ulong for this - we just need to make sure the lock bit always ends up in the
56  * first byte.
57  */
58 
59 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
60 #define BUCKET_LOCK_BITNR	0
61 #else
62 #define BUCKET_LOCK_BITNR	(BITS_PER_LONG - 1)
63 #endif
64 
65 union ulong_byte_assert {
66 	ulong	ulong;
67 	u8	byte;
68 };
69 
70 static inline void bucket_unlock(struct bucket *b)
71 {
72 	BUILD_BUG_ON(!((union ulong_byte_assert) { .ulong = 1UL << BUCKET_LOCK_BITNR }).byte);
73 
74 	clear_bit_unlock(BUCKET_LOCK_BITNR, (void *) &b->lock);
75 	wake_up_bit((void *) &b->lock, BUCKET_LOCK_BITNR);
76 }
77 
78 static inline void bucket_lock(struct bucket *b)
79 {
80 	wait_on_bit_lock((void *) &b->lock, BUCKET_LOCK_BITNR,
81 			 TASK_UNINTERRUPTIBLE);
82 }
83 
84 static inline struct bucket_array *gc_bucket_array(struct bch_dev *ca)
85 {
86 	return rcu_dereference_check(ca->buckets_gc,
87 				     !ca->fs ||
88 				     percpu_rwsem_is_held(&ca->fs->mark_lock) ||
89 				     lockdep_is_held(&ca->fs->gc_lock) ||
90 				     lockdep_is_held(&ca->bucket_lock));
91 }
92 
93 static inline struct bucket *gc_bucket(struct bch_dev *ca, size_t b)
94 {
95 	struct bucket_array *buckets = gc_bucket_array(ca);
96 
97 	BUG_ON(b < buckets->first_bucket || b >= buckets->nbuckets);
98 	return buckets->b + b;
99 }
100 
101 static inline struct bucket_gens *bucket_gens(struct bch_dev *ca)
102 {
103 	return rcu_dereference_check(ca->bucket_gens,
104 				     !ca->fs ||
105 				     percpu_rwsem_is_held(&ca->fs->mark_lock) ||
106 				     lockdep_is_held(&ca->fs->gc_lock) ||
107 				     lockdep_is_held(&ca->bucket_lock));
108 }
109 
110 static inline u8 *bucket_gen(struct bch_dev *ca, size_t b)
111 {
112 	struct bucket_gens *gens = bucket_gens(ca);
113 
114 	BUG_ON(b < gens->first_bucket || b >= gens->nbuckets);
115 	return gens->b + b;
116 }
117 
118 static inline size_t PTR_BUCKET_NR(const struct bch_dev *ca,
119 				   const struct bch_extent_ptr *ptr)
120 {
121 	return sector_to_bucket(ca, ptr->offset);
122 }
123 
124 static inline struct bpos PTR_BUCKET_POS(const struct bch_fs *c,
125 				   const struct bch_extent_ptr *ptr)
126 {
127 	struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
128 
129 	return POS(ptr->dev, PTR_BUCKET_NR(ca, ptr));
130 }
131 
132 static inline struct bpos PTR_BUCKET_POS_OFFSET(const struct bch_fs *c,
133 						const struct bch_extent_ptr *ptr,
134 						u32 *bucket_offset)
135 {
136 	struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
137 
138 	return POS(ptr->dev, sector_to_bucket_and_offset(ca, ptr->offset, bucket_offset));
139 }
140 
141 static inline struct bucket *PTR_GC_BUCKET(struct bch_dev *ca,
142 					   const struct bch_extent_ptr *ptr)
143 {
144 	return gc_bucket(ca, PTR_BUCKET_NR(ca, ptr));
145 }
146 
147 static inline enum bch_data_type ptr_data_type(const struct bkey *k,
148 					       const struct bch_extent_ptr *ptr)
149 {
150 	if (bkey_is_btree_ptr(k))
151 		return BCH_DATA_btree;
152 
153 	return ptr->cached ? BCH_DATA_cached : BCH_DATA_user;
154 }
155 
156 static inline s64 ptr_disk_sectors(s64 sectors, struct extent_ptr_decoded p)
157 {
158 	EBUG_ON(sectors < 0);
159 
160 	return crc_is_compressed(p.crc)
161 		? DIV_ROUND_UP_ULL(sectors * p.crc.compressed_size,
162 				   p.crc.uncompressed_size)
163 		: sectors;
164 }
165 
166 static inline int gen_cmp(u8 a, u8 b)
167 {
168 	return (s8) (a - b);
169 }
170 
171 static inline int gen_after(u8 a, u8 b)
172 {
173 	int r = gen_cmp(a, b);
174 
175 	return r > 0 ? r : 0;
176 }
177 
178 /**
179  * ptr_stale() - check if a pointer points into a bucket that has been
180  * invalidated.
181  */
182 static inline u8 ptr_stale(struct bch_dev *ca,
183 			   const struct bch_extent_ptr *ptr)
184 {
185 	u8 ret;
186 
187 	rcu_read_lock();
188 	ret = gen_after(*bucket_gen(ca, PTR_BUCKET_NR(ca, ptr)), ptr->gen);
189 	rcu_read_unlock();
190 
191 	return ret;
192 }
193 
194 /* Device usage: */
195 
196 void bch2_dev_usage_read_fast(struct bch_dev *, struct bch_dev_usage *);
197 static inline struct bch_dev_usage bch2_dev_usage_read(struct bch_dev *ca)
198 {
199 	struct bch_dev_usage ret;
200 
201 	bch2_dev_usage_read_fast(ca, &ret);
202 	return ret;
203 }
204 
205 void bch2_dev_usage_init(struct bch_dev *);
206 
207 static inline u64 bch2_dev_buckets_reserved(struct bch_dev *ca, enum bch_watermark watermark)
208 {
209 	s64 reserved = 0;
210 
211 	switch (watermark) {
212 	case BCH_WATERMARK_NR:
213 		BUG();
214 	case BCH_WATERMARK_stripe:
215 		reserved += ca->mi.nbuckets >> 6;
216 		fallthrough;
217 	case BCH_WATERMARK_normal:
218 		reserved += ca->mi.nbuckets >> 6;
219 		fallthrough;
220 	case BCH_WATERMARK_copygc:
221 		reserved += ca->nr_btree_reserve;
222 		fallthrough;
223 	case BCH_WATERMARK_btree:
224 		reserved += ca->nr_btree_reserve;
225 		fallthrough;
226 	case BCH_WATERMARK_btree_copygc:
227 	case BCH_WATERMARK_reclaim:
228 		break;
229 	}
230 
231 	return reserved;
232 }
233 
234 static inline u64 dev_buckets_free(struct bch_dev *ca,
235 				   struct bch_dev_usage usage,
236 				   enum bch_watermark watermark)
237 {
238 	return max_t(s64, 0,
239 		     usage.d[BCH_DATA_free].buckets -
240 		     ca->nr_open_buckets -
241 		     bch2_dev_buckets_reserved(ca, watermark));
242 }
243 
244 static inline u64 __dev_buckets_available(struct bch_dev *ca,
245 					  struct bch_dev_usage usage,
246 					  enum bch_watermark watermark)
247 {
248 	return max_t(s64, 0,
249 		       usage.d[BCH_DATA_free].buckets
250 		     + usage.d[BCH_DATA_cached].buckets
251 		     + usage.d[BCH_DATA_need_gc_gens].buckets
252 		     + usage.d[BCH_DATA_need_discard].buckets
253 		     - ca->nr_open_buckets
254 		     - bch2_dev_buckets_reserved(ca, watermark));
255 }
256 
257 static inline u64 dev_buckets_available(struct bch_dev *ca,
258 					enum bch_watermark watermark)
259 {
260 	return __dev_buckets_available(ca, bch2_dev_usage_read(ca), watermark);
261 }
262 
263 /* Filesystem usage: */
264 
265 static inline unsigned __fs_usage_u64s(unsigned nr_replicas)
266 {
267 	return sizeof(struct bch_fs_usage) / sizeof(u64) + nr_replicas;
268 }
269 
270 static inline unsigned fs_usage_u64s(struct bch_fs *c)
271 {
272 	return __fs_usage_u64s(READ_ONCE(c->replicas.nr));
273 }
274 
275 static inline unsigned __fs_usage_online_u64s(unsigned nr_replicas)
276 {
277 	return sizeof(struct bch_fs_usage_online) / sizeof(u64) + nr_replicas;
278 }
279 
280 static inline unsigned fs_usage_online_u64s(struct bch_fs *c)
281 {
282 	return __fs_usage_online_u64s(READ_ONCE(c->replicas.nr));
283 }
284 
285 static inline unsigned dev_usage_u64s(void)
286 {
287 	return sizeof(struct bch_dev_usage) / sizeof(u64);
288 }
289 
290 u64 bch2_fs_usage_read_one(struct bch_fs *, u64 *);
291 
292 struct bch_fs_usage_online *bch2_fs_usage_read(struct bch_fs *);
293 
294 void bch2_fs_usage_acc_to_base(struct bch_fs *, unsigned);
295 
296 void bch2_fs_usage_to_text(struct printbuf *,
297 			   struct bch_fs *, struct bch_fs_usage_online *);
298 
299 u64 bch2_fs_sectors_used(struct bch_fs *, struct bch_fs_usage_online *);
300 
301 struct bch_fs_usage_short
302 bch2_fs_usage_read_short(struct bch_fs *);
303 
304 /* key/bucket marking: */
305 
306 static inline struct bch_fs_usage *fs_usage_ptr(struct bch_fs *c,
307 						unsigned journal_seq,
308 						bool gc)
309 {
310 	percpu_rwsem_assert_held(&c->mark_lock);
311 	BUG_ON(!gc && !journal_seq);
312 
313 	return this_cpu_ptr(gc
314 			    ? c->usage_gc
315 			    : c->usage[journal_seq & JOURNAL_BUF_MASK]);
316 }
317 
318 int bch2_replicas_deltas_realloc(struct btree_trans *, unsigned);
319 
320 void bch2_fs_usage_initialize(struct bch_fs *);
321 
322 int bch2_mark_metadata_bucket(struct bch_fs *, struct bch_dev *,
323 			      size_t, enum bch_data_type, unsigned,
324 			      struct gc_pos, unsigned);
325 
326 int bch2_mark_alloc(struct btree_trans *, enum btree_id, unsigned,
327 		    struct bkey_s_c, struct bkey_s_c, unsigned);
328 int bch2_mark_extent(struct btree_trans *, enum btree_id, unsigned,
329 		     struct bkey_s_c, struct bkey_s_c, unsigned);
330 int bch2_mark_stripe(struct btree_trans *, enum btree_id, unsigned,
331 		     struct bkey_s_c, struct bkey_s_c, unsigned);
332 int bch2_mark_reservation(struct btree_trans *, enum btree_id, unsigned,
333 			  struct bkey_s_c, struct bkey_s_c, unsigned);
334 int bch2_mark_reflink_p(struct btree_trans *, enum btree_id, unsigned,
335 			struct bkey_s_c, struct bkey_s_c, unsigned);
336 
337 int bch2_trans_mark_extent(struct btree_trans *, enum btree_id, unsigned, struct bkey_s_c, struct bkey_i *, unsigned);
338 int bch2_trans_mark_stripe(struct btree_trans *, enum btree_id, unsigned, struct bkey_s_c, struct bkey_i *, unsigned);
339 int bch2_trans_mark_reservation(struct btree_trans *, enum btree_id, unsigned, struct bkey_s_c, struct bkey_i *, unsigned);
340 int bch2_trans_mark_reflink_p(struct btree_trans *, enum btree_id, unsigned, struct bkey_s_c, struct bkey_i *, unsigned);
341 
342 #define mem_trigger_run_overwrite_then_insert(_fn, _trans, _btree_id, _level, _old, _new, _flags)\
343 ({												\
344 	int ret = 0;										\
345 												\
346 	if (_old.k->type)									\
347 		ret = _fn(_trans, _btree_id, _level, _old, _flags & ~BTREE_TRIGGER_INSERT);	\
348 	if (!ret && _new.k->type)								\
349 		ret = _fn(_trans, _btree_id, _level, _new, _flags & ~BTREE_TRIGGER_OVERWRITE);	\
350 	ret;											\
351 })
352 
353 #define trigger_run_overwrite_then_insert(_fn, _trans, _btree_id, _level, _old, _new, _flags)	\
354 	mem_trigger_run_overwrite_then_insert(_fn, _trans, _btree_id, _level, _old, bkey_i_to_s_c(_new), _flags)
355 
356 void bch2_trans_fs_usage_revert(struct btree_trans *, struct replicas_delta_list *);
357 int bch2_trans_fs_usage_apply(struct btree_trans *, struct replicas_delta_list *);
358 
359 int bch2_trans_mark_metadata_bucket(struct btree_trans *, struct bch_dev *,
360 				    size_t, enum bch_data_type, unsigned);
361 int bch2_trans_mark_dev_sb(struct bch_fs *, struct bch_dev *);
362 int bch2_trans_mark_dev_sbs(struct bch_fs *);
363 
364 static inline bool is_superblock_bucket(struct bch_dev *ca, u64 b)
365 {
366 	struct bch_sb_layout *layout = &ca->disk_sb.sb->layout;
367 	u64 b_offset	= bucket_to_sector(ca, b);
368 	u64 b_end	= bucket_to_sector(ca, b + 1);
369 	unsigned i;
370 
371 	if (!b)
372 		return true;
373 
374 	for (i = 0; i < layout->nr_superblocks; i++) {
375 		u64 offset = le64_to_cpu(layout->sb_offset[i]);
376 		u64 end = offset + (1 << layout->sb_max_size_bits);
377 
378 		if (!(offset >= b_end || end <= b_offset))
379 			return true;
380 	}
381 
382 	return false;
383 }
384 
385 /* disk reservations: */
386 
387 static inline void bch2_disk_reservation_put(struct bch_fs *c,
388 					     struct disk_reservation *res)
389 {
390 	if (res->sectors) {
391 		this_cpu_sub(*c->online_reserved, res->sectors);
392 		res->sectors = 0;
393 	}
394 }
395 
396 #define BCH_DISK_RESERVATION_NOFAIL		(1 << 0)
397 
398 int __bch2_disk_reservation_add(struct bch_fs *,
399 				struct disk_reservation *,
400 				u64, int);
401 
402 static inline int bch2_disk_reservation_add(struct bch_fs *c, struct disk_reservation *res,
403 					    u64 sectors, int flags)
404 {
405 #ifdef __KERNEL__
406 	u64 old, new;
407 
408 	do {
409 		old = this_cpu_read(c->pcpu->sectors_available);
410 		if (sectors > old)
411 			return __bch2_disk_reservation_add(c, res, sectors, flags);
412 
413 		new = old - sectors;
414 	} while (this_cpu_cmpxchg(c->pcpu->sectors_available, old, new) != old);
415 
416 	this_cpu_add(*c->online_reserved, sectors);
417 	res->sectors			+= sectors;
418 	return 0;
419 #else
420 	return __bch2_disk_reservation_add(c, res, sectors, flags);
421 #endif
422 }
423 
424 static inline struct disk_reservation
425 bch2_disk_reservation_init(struct bch_fs *c, unsigned nr_replicas)
426 {
427 	return (struct disk_reservation) {
428 		.sectors	= 0,
429 #if 0
430 		/* not used yet: */
431 		.gen		= c->capacity_gen,
432 #endif
433 		.nr_replicas	= nr_replicas,
434 	};
435 }
436 
437 static inline int bch2_disk_reservation_get(struct bch_fs *c,
438 					    struct disk_reservation *res,
439 					    u64 sectors, unsigned nr_replicas,
440 					    int flags)
441 {
442 	*res = bch2_disk_reservation_init(c, nr_replicas);
443 
444 	return bch2_disk_reservation_add(c, res, sectors * nr_replicas, flags);
445 }
446 
447 #define RESERVE_FACTOR	6
448 
449 static inline u64 avail_factor(u64 r)
450 {
451 	return div_u64(r << RESERVE_FACTOR, (1 << RESERVE_FACTOR) + 1);
452 }
453 
454 int bch2_dev_buckets_resize(struct bch_fs *, struct bch_dev *, u64);
455 void bch2_dev_buckets_free(struct bch_dev *);
456 int bch2_dev_buckets_alloc(struct bch_fs *, struct bch_dev *);
457 
458 #endif /* _BUCKETS_H */
459