1  /* SPDX-License-Identifier: GPL-2.0 */
2  #ifndef _BCACHEFS_DARRAY_H
3  #define _BCACHEFS_DARRAY_H
4  
5  /*
6   * Dynamic arrays:
7   *
8   * Inspired by CCAN's darray
9   */
10  
11  #include <linux/slab.h>
12  
13  #define DARRAY_PREALLOCATED(_type, _nr)					\
14  struct {								\
15  	size_t nr, size;						\
16  	_type *data;							\
17  	_type preallocated[_nr];					\
18  }
19  
20  #define DARRAY(_type) DARRAY_PREALLOCATED(_type, 0)
21  
22  typedef DARRAY(char)	darray_char;
23  typedef DARRAY(char *) darray_str;
24  
25  int __bch2_darray_resize_noprof(darray_char *, size_t, size_t, gfp_t);
26  
27  #define __bch2_darray_resize(...)	alloc_hooks(__bch2_darray_resize_noprof(__VA_ARGS__))
28  
29  #define __darray_resize(_d, _element_size, _new_size, _gfp)		\
30  	(unlikely((_new_size) > (_d)->size)				\
31  	 ? __bch2_darray_resize((_d), (_element_size), (_new_size), (_gfp))\
32  	 : 0)
33  
34  #define darray_resize_gfp(_d, _new_size, _gfp)				\
35  	__darray_resize((darray_char *) (_d), sizeof((_d)->data[0]), (_new_size), _gfp)
36  
37  #define darray_resize(_d, _new_size)					\
38  	darray_resize_gfp(_d, _new_size, GFP_KERNEL)
39  
40  #define darray_make_room_gfp(_d, _more, _gfp)				\
41  	darray_resize_gfp((_d), (_d)->nr + (_more), _gfp)
42  
43  #define darray_make_room(_d, _more)					\
44  	darray_make_room_gfp(_d, _more, GFP_KERNEL)
45  
46  #define darray_room(_d)		((_d).size - (_d).nr)
47  
48  #define darray_top(_d)		((_d).data[(_d).nr])
49  
50  #define darray_push_gfp(_d, _item, _gfp)				\
51  ({									\
52  	int _ret = darray_make_room_gfp((_d), 1, _gfp);			\
53  									\
54  	if (!_ret)							\
55  		(_d)->data[(_d)->nr++] = (_item);			\
56  	_ret;								\
57  })
58  
59  #define darray_push(_d, _item)	darray_push_gfp(_d, _item, GFP_KERNEL)
60  
61  #define darray_pop(_d)		((_d)->data[--(_d)->nr])
62  
63  #define darray_first(_d)	((_d).data[0])
64  #define darray_last(_d)		((_d).data[(_d).nr - 1])
65  
66  #define darray_insert_item(_d, pos, _item)				\
67  ({									\
68  	size_t _pos = (pos);						\
69  	int _ret = darray_make_room((_d), 1);				\
70  									\
71  	if (!_ret)							\
72  		array_insert_item((_d)->data, (_d)->nr, _pos, (_item));	\
73  	_ret;								\
74  })
75  
76  #define darray_remove_item(_d, _pos)					\
77  	array_remove_item((_d)->data, (_d)->nr, (_pos) - (_d)->data)
78  
79  #define __darray_for_each(_d, _i)						\
80  	for ((_i) = (_d).data; _i < (_d).data + (_d).nr; _i++)
81  
82  #define darray_for_each(_d, _i)						\
83  	for (typeof(&(_d).data[0]) _i = (_d).data; _i < (_d).data + (_d).nr; _i++)
84  
85  #define darray_for_each_reverse(_d, _i)					\
86  	for (typeof(&(_d).data[0]) _i = (_d).data + (_d).nr - 1; _i >= (_d).data; --_i)
87  
88  #define darray_init(_d)							\
89  do {									\
90  	(_d)->nr = 0;							\
91  	(_d)->size = ARRAY_SIZE((_d)->preallocated);			\
92  	(_d)->data = (_d)->size ? (_d)->preallocated : NULL;		\
93  } while (0)
94  
95  #define darray_exit(_d)							\
96  do {									\
97  	if (!ARRAY_SIZE((_d)->preallocated) ||				\
98  	    (_d)->data != (_d)->preallocated)				\
99  		kvfree((_d)->data);					\
100  	darray_init(_d);						\
101  } while (0)
102  
103  #endif /* _BCACHEFS_DARRAY_H */
104