xref: /linux/fs/bcachefs/vstructs.h (revision dbcedec3a31119d7594baacc743300d127c99c56)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _VSTRUCTS_H
3 #define _VSTRUCTS_H
4 
5 #include "util.h"
6 
7 /*
8  * NOTE: we can't differentiate between __le64 and u64 with type_is - this
9  * assumes u64 is little endian:
10  */
11 #define __vstruct_u64s(_s)						\
12 ({									\
13 	( type_is((_s)->u64s, u64) ? le64_to_cpu((__force __le64) (_s)->u64s)		\
14 	: type_is((_s)->u64s, u32) ? le32_to_cpu((__force __le32) (_s)->u64s)		\
15 	: type_is((_s)->u64s, u16) ? le16_to_cpu((__force __le16) (_s)->u64s)		\
16 	: ((__force u8) ((_s)->u64s)));						\
17 })
18 
19 #define __vstruct_bytes(_type, _u64s)					\
20 ({									\
21 	BUILD_BUG_ON(offsetof(_type, _data) % sizeof(u64));		\
22 									\
23 	(size_t) (offsetof(_type, _data) + (_u64s) * sizeof(u64));	\
24 })
25 
26 #define vstruct_bytes(_s)						\
27 	__vstruct_bytes(typeof(*(_s)), __vstruct_u64s(_s))
28 
29 #define __vstruct_blocks(_type, _sector_block_bits, _u64s)		\
30 	(round_up(__vstruct_bytes(_type, _u64s),			\
31 		  512 << (_sector_block_bits)) >> (9 + (_sector_block_bits)))
32 
33 #define vstruct_blocks(_s, _sector_block_bits)				\
34 	__vstruct_blocks(typeof(*(_s)), _sector_block_bits, __vstruct_u64s(_s))
35 
36 #define vstruct_blocks_plus(_s, _sector_block_bits, _u64s)		\
37 	__vstruct_blocks(typeof(*(_s)), _sector_block_bits,		\
38 			 __vstruct_u64s(_s) + (_u64s))
39 
40 #define vstruct_sectors(_s, _sector_block_bits)				\
41 	(round_up(vstruct_bytes(_s), 512 << (_sector_block_bits)) >> 9)
42 
43 #define vstruct_next(_s)						\
44 	((typeof(_s))			((u64 *) (_s)->_data + __vstruct_u64s(_s)))
45 #define vstruct_last(_s)						\
46 	((typeof(&(_s)->start[0]))	((u64 *) (_s)->_data + __vstruct_u64s(_s)))
47 #define vstruct_end(_s)							\
48 	((void *)			((u64 *) (_s)->_data + __vstruct_u64s(_s)))
49 
50 #define vstruct_for_each(_s, _i)					\
51 	for (typeof(&(_s)->start[0]) _i = (_s)->start;			\
52 	     _i < vstruct_last(_s);					\
53 	     _i = vstruct_next(_i))
54 
55 #define vstruct_for_each_safe(_s, _i)					\
56 	for (typeof(&(_s)->start[0]) _next, _i = (_s)->start;		\
57 	     _i < vstruct_last(_s) && (_next = vstruct_next(_i), true);	\
58 	     _i = _next)
59 
60 #define vstruct_idx(_s, _idx)						\
61 	((typeof(&(_s)->start[0])) ((_s)->_data + (_idx)))
62 
63 #endif /* _VSTRUCTS_H */
64