bcachefs: Prep work for variable size btree node buffers
[sfrench/cifs-2.6.git] / fs / bcachefs / backpointers.h
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 "super.h"
10
11 static inline u64 swab40(u64 x)
12 {
13         return (((x & 0x00000000ffULL) << 32)|
14                 ((x & 0x000000ff00ULL) << 16)|
15                 ((x & 0x0000ff0000ULL) >>  0)|
16                 ((x & 0x00ff000000ULL) >> 16)|
17                 ((x & 0xff00000000ULL) >> 32));
18 }
19
20 int bch2_backpointer_invalid(struct bch_fs *, struct bkey_s_c k,
21                              enum bkey_invalid_flags, struct printbuf *);
22 void bch2_backpointer_to_text(struct printbuf *, const struct bch_backpointer *);
23 void bch2_backpointer_k_to_text(struct printbuf *, struct bch_fs *, struct bkey_s_c);
24 void bch2_backpointer_swab(struct bkey_s);
25
26 #define bch2_bkey_ops_backpointer ((struct bkey_ops) {  \
27         .key_invalid    = bch2_backpointer_invalid,     \
28         .val_to_text    = bch2_backpointer_k_to_text,   \
29         .swab           = bch2_backpointer_swab,        \
30         .min_val_size   = 32,                           \
31 })
32
33 #define MAX_EXTENT_COMPRESS_RATIO_SHIFT         10
34
35 /*
36  * Convert from pos in backpointer btree to pos of corresponding bucket in alloc
37  * btree:
38  */
39 static inline struct bpos bp_pos_to_bucket(const struct bch_fs *c,
40                                            struct bpos bp_pos)
41 {
42         struct bch_dev *ca = bch_dev_bkey_exists(c, bp_pos.inode);
43         u64 bucket_sector = bp_pos.offset >> MAX_EXTENT_COMPRESS_RATIO_SHIFT;
44
45         return POS(bp_pos.inode, sector_to_bucket(ca, bucket_sector));
46 }
47
48 /*
49  * Convert from pos in alloc btree + bucket offset to pos in backpointer btree:
50  */
51 static inline struct bpos bucket_pos_to_bp(const struct bch_fs *c,
52                                            struct bpos bucket,
53                                            u64 bucket_offset)
54 {
55         struct bch_dev *ca = bch_dev_bkey_exists(c, bucket.inode);
56         struct bpos ret;
57
58         ret = POS(bucket.inode,
59                   (bucket_to_sector(ca, bucket.offset) <<
60                    MAX_EXTENT_COMPRESS_RATIO_SHIFT) + bucket_offset);
61
62         EBUG_ON(!bkey_eq(bucket, bp_pos_to_bucket(c, ret)));
63
64         return ret;
65 }
66
67 int bch2_bucket_backpointer_mod_nowritebuffer(struct btree_trans *, struct bpos bucket,
68                                 struct bch_backpointer, struct bkey_s_c, bool);
69
70 static inline int bch2_bucket_backpointer_mod(struct btree_trans *trans,
71                                 struct bpos bucket,
72                                 struct bch_backpointer bp,
73                                 struct bkey_s_c orig_k,
74                                 bool insert)
75 {
76         if (unlikely(bch2_backpointers_no_use_write_buffer))
77                 return bch2_bucket_backpointer_mod_nowritebuffer(trans, bucket, bp, orig_k, insert);
78
79         struct bkey_i_backpointer bp_k;
80
81         bkey_backpointer_init(&bp_k.k_i);
82         bp_k.k.p = bucket_pos_to_bp(trans->c, bucket, bp.bucket_offset);
83         bp_k.v = bp;
84
85         if (!insert) {
86                 bp_k.k.type = KEY_TYPE_deleted;
87                 set_bkey_val_u64s(&bp_k.k, 0);
88         }
89
90         return bch2_trans_update_buffered(trans, BTREE_ID_backpointers, &bp_k.k_i);
91 }
92
93 static inline enum bch_data_type bkey_ptr_data_type(enum btree_id btree_id, unsigned level,
94                                                     struct bkey_s_c k, struct extent_ptr_decoded p)
95 {
96         return  level           ? BCH_DATA_btree :
97                 p.has_ec        ? BCH_DATA_stripe :
98                                   BCH_DATA_user;
99 }
100
101 static inline void bch2_extent_ptr_to_bp(struct bch_fs *c,
102                            enum btree_id btree_id, unsigned level,
103                            struct bkey_s_c k, struct extent_ptr_decoded p,
104                            struct bpos *bucket_pos, struct bch_backpointer *bp)
105 {
106         enum bch_data_type data_type = bkey_ptr_data_type(btree_id, level, k, p);
107         s64 sectors = level ? btree_sectors(c) : k.k->size;
108         u32 bucket_offset;
109
110         *bucket_pos = PTR_BUCKET_POS_OFFSET(c, &p.ptr, &bucket_offset);
111         *bp = (struct bch_backpointer) {
112                 .btree_id       = btree_id,
113                 .level          = level,
114                 .data_type      = data_type,
115                 .bucket_offset  = ((u64) bucket_offset << MAX_EXTENT_COMPRESS_RATIO_SHIFT) +
116                         p.crc.offset,
117                 .bucket_len     = ptr_disk_sectors(sectors, p),
118                 .pos            = k.k->p,
119         };
120 }
121
122 int bch2_get_next_backpointer(struct btree_trans *, struct bpos, int,
123                               struct bpos *, struct bch_backpointer *, unsigned);
124 struct bkey_s_c bch2_backpointer_get_key(struct btree_trans *, struct btree_iter *,
125                                          struct bpos, struct bch_backpointer,
126                                          unsigned);
127 struct btree *bch2_backpointer_get_node(struct btree_trans *, struct btree_iter *,
128                                         struct bpos, struct bch_backpointer);
129
130 int bch2_check_btree_backpointers(struct bch_fs *);
131 int bch2_check_extents_to_backpointers(struct bch_fs *);
132 int bch2_check_backpointers_to_extents(struct bch_fs *);
133
134 #endif /* _BCACHEFS_BACKPOINTERS_BACKGROUND_H */