xref: /linux/fs/bcachefs/backpointers.h (revision 001821b0e79716c4e17c71d8e053a23599a7a508)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _BCACHEFS_BACKPOINTERS_BACKGROUND_H
3 #define _BCACHEFS_BACKPOINTERS_BACKGROUND_H
4 
5 #include "btree_cache.h"
6 #include "btree_iter.h"
7 #include "btree_update.h"
8 #include "buckets.h"
9 #include "error.h"
10 #include "super.h"
11 
12 static inline u64 swab40(u64 x)
13 {
14 	return (((x & 0x00000000ffULL) << 32)|
15 		((x & 0x000000ff00ULL) << 16)|
16 		((x & 0x0000ff0000ULL) >>  0)|
17 		((x & 0x00ff000000ULL) >> 16)|
18 		((x & 0xff00000000ULL) >> 32));
19 }
20 
21 int bch2_backpointer_invalid(struct bch_fs *, struct bkey_s_c k,
22 			     enum bch_validate_flags, struct printbuf *);
23 void bch2_backpointer_to_text(struct printbuf *, const struct bch_backpointer *);
24 void bch2_backpointer_k_to_text(struct printbuf *, struct bch_fs *, struct bkey_s_c);
25 void bch2_backpointer_swab(struct bkey_s);
26 
27 #define bch2_bkey_ops_backpointer ((struct bkey_ops) {	\
28 	.key_invalid	= bch2_backpointer_invalid,	\
29 	.val_to_text	= bch2_backpointer_k_to_text,	\
30 	.swab		= bch2_backpointer_swab,	\
31 	.min_val_size	= 32,				\
32 })
33 
34 #define MAX_EXTENT_COMPRESS_RATIO_SHIFT		10
35 
36 /*
37  * Convert from pos in backpointer btree to pos of corresponding bucket in alloc
38  * btree:
39  */
40 static inline struct bpos bp_pos_to_bucket(const struct bch_dev *ca, struct bpos bp_pos)
41 {
42 	u64 bucket_sector = bp_pos.offset >> MAX_EXTENT_COMPRESS_RATIO_SHIFT;
43 
44 	return POS(bp_pos.inode, sector_to_bucket(ca, bucket_sector));
45 }
46 
47 static inline bool bp_pos_to_bucket_nodev_noerror(struct bch_fs *c, struct bpos bp_pos, struct bpos *bucket)
48 {
49 	rcu_read_lock();
50 	struct bch_dev *ca = bch2_dev_rcu(c, bp_pos.inode);
51 	if (ca)
52 		*bucket = bp_pos_to_bucket(ca, bp_pos);
53 	rcu_read_unlock();
54 	return ca != NULL;
55 }
56 
57 static inline bool bp_pos_to_bucket_nodev(struct bch_fs *c, struct bpos bp_pos, struct bpos *bucket)
58 {
59 	return !bch2_fs_inconsistent_on(!bp_pos_to_bucket_nodev_noerror(c, bp_pos, bucket),
60 					c, "backpointer for missing device %llu", bp_pos.inode);
61 }
62 
63 static inline struct bpos bucket_pos_to_bp_noerror(const struct bch_dev *ca,
64 						   struct bpos bucket,
65 						   u64 bucket_offset)
66 {
67 	return POS(bucket.inode,
68 		   (bucket_to_sector(ca, bucket.offset) <<
69 		    MAX_EXTENT_COMPRESS_RATIO_SHIFT) + bucket_offset);
70 }
71 
72 /*
73  * Convert from pos in alloc btree + bucket offset to pos in backpointer btree:
74  */
75 static inline struct bpos bucket_pos_to_bp(const struct bch_dev *ca,
76 					   struct bpos bucket,
77 					   u64 bucket_offset)
78 {
79 	struct bpos ret = bucket_pos_to_bp_noerror(ca, bucket, bucket_offset);
80 	EBUG_ON(!bkey_eq(bucket, bp_pos_to_bucket(ca, ret)));
81 	return ret;
82 }
83 
84 int bch2_bucket_backpointer_mod_nowritebuffer(struct btree_trans *, struct bch_dev *,
85 				struct bpos bucket, struct bch_backpointer, struct bkey_s_c, bool);
86 
87 static inline int bch2_bucket_backpointer_mod(struct btree_trans *trans,
88 				struct bch_dev *ca,
89 				struct bpos bucket,
90 				struct bch_backpointer bp,
91 				struct bkey_s_c orig_k,
92 				bool insert)
93 {
94 	if (unlikely(bch2_backpointers_no_use_write_buffer))
95 		return bch2_bucket_backpointer_mod_nowritebuffer(trans, ca, bucket, bp, orig_k, insert);
96 
97 	struct bkey_i_backpointer bp_k;
98 
99 	bkey_backpointer_init(&bp_k.k_i);
100 	bp_k.k.p = bucket_pos_to_bp(ca, bucket, bp.bucket_offset);
101 	bp_k.v = bp;
102 
103 	if (!insert) {
104 		bp_k.k.type = KEY_TYPE_deleted;
105 		set_bkey_val_u64s(&bp_k.k, 0);
106 	}
107 
108 	return bch2_trans_update_buffered(trans, BTREE_ID_backpointers, &bp_k.k_i);
109 }
110 
111 static inline enum bch_data_type bch2_bkey_ptr_data_type(struct bkey_s_c k,
112 							 struct extent_ptr_decoded p,
113 							 const union bch_extent_entry *entry)
114 {
115 	switch (k.k->type) {
116 	case KEY_TYPE_btree_ptr:
117 	case KEY_TYPE_btree_ptr_v2:
118 		return BCH_DATA_btree;
119 	case KEY_TYPE_extent:
120 	case KEY_TYPE_reflink_v:
121 		return p.has_ec ? BCH_DATA_stripe : BCH_DATA_user;
122 	case KEY_TYPE_stripe: {
123 		const struct bch_extent_ptr *ptr = &entry->ptr;
124 		struct bkey_s_c_stripe s = bkey_s_c_to_stripe(k);
125 
126 		BUG_ON(ptr < s.v->ptrs ||
127 		       ptr >= s.v->ptrs + s.v->nr_blocks);
128 
129 		return ptr >= s.v->ptrs + s.v->nr_blocks - s.v->nr_redundant
130 			? BCH_DATA_parity
131 			: BCH_DATA_user;
132 	}
133 	default:
134 		BUG();
135 	}
136 }
137 
138 static inline void bch2_extent_ptr_to_bp(struct bch_fs *c, struct bch_dev *ca,
139 			   enum btree_id btree_id, unsigned level,
140 			   struct bkey_s_c k, struct extent_ptr_decoded p,
141 			   const union bch_extent_entry *entry,
142 			   struct bpos *bucket_pos, struct bch_backpointer *bp)
143 {
144 	enum bch_data_type data_type = bch2_bkey_ptr_data_type(k, p, entry);
145 	s64 sectors = level ? btree_sectors(c) : k.k->size;
146 	u32 bucket_offset;
147 
148 	*bucket_pos = PTR_BUCKET_POS_OFFSET(ca, &p.ptr, &bucket_offset);
149 	*bp = (struct bch_backpointer) {
150 		.btree_id	= btree_id,
151 		.level		= level,
152 		.data_type	= data_type,
153 		.bucket_offset	= ((u64) bucket_offset << MAX_EXTENT_COMPRESS_RATIO_SHIFT) +
154 			p.crc.offset,
155 		.bucket_len	= ptr_disk_sectors(sectors, p),
156 		.pos		= k.k->p,
157 	};
158 }
159 
160 int bch2_get_next_backpointer(struct btree_trans *, struct bch_dev *ca, struct bpos, int,
161 			      struct bpos *, struct bch_backpointer *, unsigned);
162 struct bkey_s_c bch2_backpointer_get_key(struct btree_trans *, struct btree_iter *,
163 					 struct bpos, struct bch_backpointer,
164 					 unsigned);
165 struct btree *bch2_backpointer_get_node(struct btree_trans *, struct btree_iter *,
166 					struct bpos, struct bch_backpointer);
167 
168 int bch2_check_btree_backpointers(struct bch_fs *);
169 int bch2_check_extents_to_backpointers(struct bch_fs *);
170 int bch2_check_backpointers_to_extents(struct bch_fs *);
171 
172 #endif /* _BCACHEFS_BACKPOINTERS_BACKGROUND_H */
173