xref: /linux/fs/bcachefs/buckets.h (revision 06a130e42a5bfc84795464bff023bff4c16f58c5)
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 u64 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 u64 sector_to_bucket_and_offset(const struct bch_dev *ca, sector_t s, u32 *offset)
34 {
35 	return div_u64_rem(s, ca->mi.bucket_size, offset);
36 }
37 
38 #define for_each_bucket(_b, _buckets)				\
39 	for (_b = (_buckets)->b + (_buckets)->first_bucket;	\
40 	     _b < (_buckets)->b + (_buckets)->nbuckets; _b++)
41 
42 /*
43  * Ugly hack alert:
44  *
45  * We need to cram a spinlock in a single byte, because that's what we have left
46  * in struct bucket, and we care about the size of these - during fsck, we need
47  * in memory state for every single bucket on every device.
48  *
49  * We used to do
50  *   while (xchg(&b->lock, 1) cpu_relax();
51  * but, it turns out not all architectures support xchg on a single byte.
52  *
53  * So now we use bit_spin_lock(), with fun games since we can't burn a whole
54  * ulong for this - we just need to make sure the lock bit always ends up in the
55  * first byte.
56  */
57 
58 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
59 #define BUCKET_LOCK_BITNR	0
60 #else
61 #define BUCKET_LOCK_BITNR	(BITS_PER_LONG - 1)
62 #endif
63 
64 union ulong_byte_assert {
65 	ulong	ulong;
66 	u8	byte;
67 };
68 
69 static inline void bucket_unlock(struct bucket *b)
70 {
71 	BUILD_BUG_ON(!((union ulong_byte_assert) { .ulong = 1UL << BUCKET_LOCK_BITNR }).byte);
72 
73 	clear_bit_unlock(BUCKET_LOCK_BITNR, (void *) &b->lock);
74 	wake_up_bit((void *) &b->lock, BUCKET_LOCK_BITNR);
75 }
76 
77 static inline void bucket_lock(struct bucket *b)
78 {
79 	wait_on_bit_lock((void *) &b->lock, BUCKET_LOCK_BITNR,
80 			 TASK_UNINTERRUPTIBLE);
81 }
82 
83 static inline struct bucket *gc_bucket(struct bch_dev *ca, size_t b)
84 {
85 	return genradix_ptr(&ca->buckets_gc, b);
86 }
87 
88 static inline struct bucket_gens *bucket_gens(struct bch_dev *ca)
89 {
90 	return rcu_dereference_check(ca->bucket_gens,
91 				     !ca->fs ||
92 				     percpu_rwsem_is_held(&ca->fs->mark_lock) ||
93 				     lockdep_is_held(&ca->fs->state_lock) ||
94 				     lockdep_is_held(&ca->bucket_lock));
95 }
96 
97 static inline u8 *bucket_gen(struct bch_dev *ca, size_t b)
98 {
99 	struct bucket_gens *gens = bucket_gens(ca);
100 
101 	if (b - gens->first_bucket >= gens->nbuckets_minus_first)
102 		return NULL;
103 	return gens->b + b;
104 }
105 
106 static inline u8 bucket_gen_get(struct bch_dev *ca, size_t b)
107 {
108 	rcu_read_lock();
109 	u8 gen = *bucket_gen(ca, b);
110 	rcu_read_unlock();
111 	return gen;
112 }
113 
114 static inline size_t PTR_BUCKET_NR(const struct bch_dev *ca,
115 				   const struct bch_extent_ptr *ptr)
116 {
117 	return sector_to_bucket(ca, ptr->offset);
118 }
119 
120 static inline struct bpos PTR_BUCKET_POS(const struct bch_dev *ca,
121 					 const struct bch_extent_ptr *ptr)
122 {
123 	return POS(ptr->dev, PTR_BUCKET_NR(ca, ptr));
124 }
125 
126 static inline struct bpos PTR_BUCKET_POS_OFFSET(const struct bch_dev *ca,
127 						const struct bch_extent_ptr *ptr,
128 						u32 *bucket_offset)
129 {
130 	return POS(ptr->dev, sector_to_bucket_and_offset(ca, ptr->offset, bucket_offset));
131 }
132 
133 static inline struct bucket *PTR_GC_BUCKET(struct bch_dev *ca,
134 					   const struct bch_extent_ptr *ptr)
135 {
136 	return gc_bucket(ca, PTR_BUCKET_NR(ca, ptr));
137 }
138 
139 static inline enum bch_data_type ptr_data_type(const struct bkey *k,
140 					       const struct bch_extent_ptr *ptr)
141 {
142 	if (bkey_is_btree_ptr(k))
143 		return BCH_DATA_btree;
144 
145 	return ptr->cached ? BCH_DATA_cached : BCH_DATA_user;
146 }
147 
148 static inline s64 ptr_disk_sectors(s64 sectors, struct extent_ptr_decoded p)
149 {
150 	EBUG_ON(sectors < 0);
151 
152 	return crc_is_compressed(p.crc)
153 		? DIV_ROUND_UP_ULL(sectors * p.crc.compressed_size,
154 				   p.crc.uncompressed_size)
155 		: sectors;
156 }
157 
158 static inline int gen_cmp(u8 a, u8 b)
159 {
160 	return (s8) (a - b);
161 }
162 
163 static inline int gen_after(u8 a, u8 b)
164 {
165 	int r = gen_cmp(a, b);
166 
167 	return r > 0 ? r : 0;
168 }
169 
170 static inline int dev_ptr_stale_rcu(struct bch_dev *ca, const struct bch_extent_ptr *ptr)
171 {
172 	u8 *gen = bucket_gen(ca, PTR_BUCKET_NR(ca, ptr));
173 	if (!gen)
174 		return -1;
175 	return gen_after(*gen, ptr->gen);
176 }
177 
178 /**
179  * dev_ptr_stale() - check if a pointer points into a bucket that has been
180  * invalidated.
181  */
182 static inline int dev_ptr_stale(struct bch_dev *ca, const struct bch_extent_ptr *ptr)
183 {
184 	rcu_read_lock();
185 	int ret = dev_ptr_stale_rcu(ca, ptr);
186 	rcu_read_unlock();
187 
188 	return ret;
189 }
190 
191 /* Device usage: */
192 
193 void bch2_dev_usage_read_fast(struct bch_dev *, struct bch_dev_usage *);
194 static inline struct bch_dev_usage bch2_dev_usage_read(struct bch_dev *ca)
195 {
196 	struct bch_dev_usage ret;
197 
198 	bch2_dev_usage_read_fast(ca, &ret);
199 	return ret;
200 }
201 
202 void bch2_dev_usage_to_text(struct printbuf *, struct bch_dev *, struct bch_dev_usage *);
203 
204 static inline u64 bch2_dev_buckets_reserved(struct bch_dev *ca, enum bch_watermark watermark)
205 {
206 	s64 reserved = 0;
207 
208 	switch (watermark) {
209 	case BCH_WATERMARK_NR:
210 		BUG();
211 	case BCH_WATERMARK_stripe:
212 		reserved += ca->mi.nbuckets >> 6;
213 		fallthrough;
214 	case BCH_WATERMARK_normal:
215 		reserved += ca->mi.nbuckets >> 6;
216 		fallthrough;
217 	case BCH_WATERMARK_copygc:
218 		reserved += ca->nr_btree_reserve;
219 		fallthrough;
220 	case BCH_WATERMARK_btree:
221 		reserved += ca->nr_btree_reserve;
222 		fallthrough;
223 	case BCH_WATERMARK_btree_copygc:
224 	case BCH_WATERMARK_reclaim:
225 	case BCH_WATERMARK_interior_updates:
226 		break;
227 	}
228 
229 	return reserved;
230 }
231 
232 static inline u64 dev_buckets_free(struct bch_dev *ca,
233 				   struct bch_dev_usage usage,
234 				   enum bch_watermark watermark)
235 {
236 	return max_t(s64, 0,
237 		     usage.d[BCH_DATA_free].buckets -
238 		     ca->nr_open_buckets -
239 		     bch2_dev_buckets_reserved(ca, watermark));
240 }
241 
242 static inline u64 __dev_buckets_available(struct bch_dev *ca,
243 					  struct bch_dev_usage usage,
244 					  enum bch_watermark watermark)
245 {
246 	return max_t(s64, 0,
247 		       usage.d[BCH_DATA_free].buckets
248 		     + usage.d[BCH_DATA_cached].buckets
249 		     + usage.d[BCH_DATA_need_gc_gens].buckets
250 		     + usage.d[BCH_DATA_need_discard].buckets
251 		     - ca->nr_open_buckets
252 		     - bch2_dev_buckets_reserved(ca, watermark));
253 }
254 
255 static inline u64 dev_buckets_available(struct bch_dev *ca,
256 					enum bch_watermark watermark)
257 {
258 	return __dev_buckets_available(ca, bch2_dev_usage_read(ca), watermark);
259 }
260 
261 /* Filesystem usage: */
262 
263 static inline unsigned dev_usage_u64s(void)
264 {
265 	return sizeof(struct bch_dev_usage) / sizeof(u64);
266 }
267 
268 struct bch_fs_usage_short
269 bch2_fs_usage_read_short(struct bch_fs *);
270 
271 int bch2_bucket_ref_update(struct btree_trans *, struct bch_dev *,
272 			   struct bkey_s_c, const struct bch_extent_ptr *,
273 			   s64, enum bch_data_type, u8, u8, u32 *);
274 
275 int bch2_check_fix_ptrs(struct btree_trans *,
276 			enum btree_id, unsigned, struct bkey_s_c,
277 			enum btree_iter_update_trigger_flags);
278 
279 int bch2_trigger_extent(struct btree_trans *, enum btree_id, unsigned,
280 			struct bkey_s_c, struct bkey_s,
281 			enum btree_iter_update_trigger_flags);
282 int bch2_trigger_reservation(struct btree_trans *, enum btree_id, unsigned,
283 			  struct bkey_s_c, struct bkey_s,
284 			  enum btree_iter_update_trigger_flags);
285 
286 #define trigger_run_overwrite_then_insert(_fn, _trans, _btree_id, _level, _old, _new, _flags)\
287 ({												\
288 	int ret = 0;										\
289 												\
290 	if (_old.k->type)									\
291 		ret = _fn(_trans, _btree_id, _level, _old, _flags & ~BTREE_TRIGGER_insert);	\
292 	if (!ret && _new.k->type)								\
293 		ret = _fn(_trans, _btree_id, _level, _new.s_c, _flags & ~BTREE_TRIGGER_overwrite);\
294 	ret;											\
295 })
296 
297 void bch2_trans_account_disk_usage_change(struct btree_trans *);
298 
299 int bch2_trans_mark_metadata_bucket(struct btree_trans *, struct bch_dev *, u64,
300 				    enum bch_data_type, unsigned,
301 				    enum btree_iter_update_trigger_flags);
302 int bch2_trans_mark_dev_sb(struct bch_fs *, struct bch_dev *,
303 				    enum btree_iter_update_trigger_flags);
304 int bch2_trans_mark_dev_sbs_flags(struct bch_fs *,
305 				    enum btree_iter_update_trigger_flags);
306 int bch2_trans_mark_dev_sbs(struct bch_fs *);
307 
308 static inline bool is_superblock_bucket(struct bch_dev *ca, u64 b)
309 {
310 	struct bch_sb_layout *layout = &ca->disk_sb.sb->layout;
311 	u64 b_offset	= bucket_to_sector(ca, b);
312 	u64 b_end	= bucket_to_sector(ca, b + 1);
313 	unsigned i;
314 
315 	if (!b)
316 		return true;
317 
318 	for (i = 0; i < layout->nr_superblocks; i++) {
319 		u64 offset = le64_to_cpu(layout->sb_offset[i]);
320 		u64 end = offset + (1 << layout->sb_max_size_bits);
321 
322 		if (!(offset >= b_end || end <= b_offset))
323 			return true;
324 	}
325 
326 	return false;
327 }
328 
329 static inline const char *bch2_data_type_str(enum bch_data_type type)
330 {
331 	return type < BCH_DATA_NR
332 		? __bch2_data_types[type]
333 		: "(invalid data type)";
334 }
335 
336 /* disk reservations: */
337 
338 static inline void bch2_disk_reservation_put(struct bch_fs *c,
339 					     struct disk_reservation *res)
340 {
341 	if (res->sectors) {
342 		this_cpu_sub(*c->online_reserved, res->sectors);
343 		res->sectors = 0;
344 	}
345 }
346 
347 #define BCH_DISK_RESERVATION_NOFAIL		(1 << 0)
348 
349 int __bch2_disk_reservation_add(struct bch_fs *,
350 				struct disk_reservation *,
351 				u64, int);
352 
353 static inline int bch2_disk_reservation_add(struct bch_fs *c, struct disk_reservation *res,
354 					    u64 sectors, int flags)
355 {
356 #ifdef __KERNEL__
357 	u64 old, new;
358 
359 	old = this_cpu_read(c->pcpu->sectors_available);
360 	do {
361 		if (sectors > old)
362 			return __bch2_disk_reservation_add(c, res, sectors, flags);
363 
364 		new = old - sectors;
365 	} while (!this_cpu_try_cmpxchg(c->pcpu->sectors_available, &old, new));
366 
367 	this_cpu_add(*c->online_reserved, sectors);
368 	res->sectors			+= sectors;
369 	return 0;
370 #else
371 	return __bch2_disk_reservation_add(c, res, sectors, flags);
372 #endif
373 }
374 
375 static inline struct disk_reservation
376 bch2_disk_reservation_init(struct bch_fs *c, unsigned nr_replicas)
377 {
378 	return (struct disk_reservation) {
379 		.sectors	= 0,
380 #if 0
381 		/* not used yet: */
382 		.gen		= c->capacity_gen,
383 #endif
384 		.nr_replicas	= nr_replicas,
385 	};
386 }
387 
388 static inline int bch2_disk_reservation_get(struct bch_fs *c,
389 					    struct disk_reservation *res,
390 					    u64 sectors, unsigned nr_replicas,
391 					    int flags)
392 {
393 	*res = bch2_disk_reservation_init(c, nr_replicas);
394 
395 	return bch2_disk_reservation_add(c, res, sectors * nr_replicas, flags);
396 }
397 
398 #define RESERVE_FACTOR	6
399 
400 static inline u64 avail_factor(u64 r)
401 {
402 	return div_u64(r << RESERVE_FACTOR, (1 << RESERVE_FACTOR) + 1);
403 }
404 
405 void bch2_buckets_nouse_free(struct bch_fs *);
406 int bch2_buckets_nouse_alloc(struct bch_fs *);
407 
408 int bch2_dev_buckets_resize(struct bch_fs *, struct bch_dev *, u64);
409 void bch2_dev_buckets_free(struct bch_dev *);
410 int bch2_dev_buckets_alloc(struct bch_fs *, struct bch_dev *);
411 
412 #endif /* _BUCKETS_H */
413