git.sesse.net Git - bcachefs-tools-debian/blob - include/linux/darray.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * (C) 2022-2024 Kent Overstreet <kent.overstreet@linux.dev>
   4  */
   5 #ifndef _LINUX_DARRAY_H
   6 #define _LINUX_DARRAY_H
   7
   8 /*
   9  * Dynamic arrays
  10  *
  11  * Inspired by CCAN's darray
  12  */
  13
  14 #include <linux/darray_types.h>
  15 #include <linux/slab.h>
  16
  17 int __darray_resize_slowpath(darray_char *, size_t, size_t, gfp_t);
  18
  19 static inline int __darray_resize(darray_char *d, size_t element_size,
  20                                   size_t new_size, gfp_t gfp)
  21 {
  22         return unlikely(new_size > d->size)
  23                 ? __darray_resize_slowpath(d, element_size, new_size, gfp)
  24                 : 0;
  25 }
  26
  27 #define darray_resize_gfp(_d, _new_size, _gfp)                          \
  28         unlikely(__darray_resize((darray_char *) (_d), sizeof((_d)->data[0]), (_new_size), _gfp))
  29
  30 #define darray_resize(_d, _new_size)                                    \
  31         darray_resize_gfp(_d, _new_size, GFP_KERNEL)
  32
  33 static inline int __darray_make_room(darray_char *d, size_t t_size, size_t more, gfp_t gfp)
  34 {
  35         return __darray_resize(d, t_size, d->nr + more, gfp);
  36 }
  37
  38 #define darray_make_room_gfp(_d, _more, _gfp)                           \
  39         __darray_make_room((darray_char *) (_d), sizeof((_d)->data[0]), (_more), _gfp)
  40
  41 #define darray_make_room(_d, _more)                                     \
  42         darray_make_room_gfp(_d, _more, GFP_KERNEL)
  43
  44 #define darray_room(_d)         ((_d).size - (_d).nr)
  45
  46 #define darray_top(_d)          ((_d).data[(_d).nr])
  47
  48 #define darray_push_gfp(_d, _item, _gfp)                                \
  49 ({                                                                      \
  50         int _ret = darray_make_room_gfp((_d), 1, _gfp);                 \
  51                                                                         \
  52         if (!_ret)                                                      \
  53                 (_d)->data[(_d)->nr++] = (_item);                       \
  54         _ret;                                                           \
  55 })
  56
  57 #define darray_push(_d, _item)  darray_push_gfp(_d, _item, GFP_KERNEL)
  58
  59 #define darray_pop(_d)          ((_d)->data[--(_d)->nr])
  60
  61 #define darray_first(_d)        ((_d).data[0])
  62 #define darray_last(_d)         ((_d).data[(_d).nr - 1])
  63
  64 /* Insert/remove items into the middle of a darray: */
  65
  66 #define array_insert_item(_array, _nr, _pos, _new_item)                 \
  67 do {                                                                    \
  68         memmove(&(_array)[(_pos) + 1],                                  \
  69                 &(_array)[(_pos)],                                      \
  70                 sizeof((_array)[0]) * ((_nr) - (_pos)));                \
  71         (_nr)++;                                                        \
  72         (_array)[(_pos)] = (_new_item);                                 \
  73 } while (0)
  74
  75 #define array_remove_items(_array, _nr, _pos, _nr_to_remove)            \
  76 do {                                                                    \
  77         (_nr) -= (_nr_to_remove);                                       \
  78         memmove(&(_array)[(_pos)],                                      \
  79                 &(_array)[(_pos) + (_nr_to_remove)],                    \
  80                 sizeof((_array)[0]) * ((_nr) - (_pos)));                \
  81 } while (0)
  82
  83 #define array_remove_item(_array, _nr, _pos)                            \
  84         array_remove_items(_array, _nr, _pos, 1)
  85
  86 #define darray_insert_item(_d, pos, _item)                              \
  87 ({                                                                      \
  88         size_t _pos = (pos);                                            \
  89         int _ret = darray_make_room((_d), 1);                           \
  90                                                                         \
  91         if (!_ret)                                                      \
  92                 array_insert_item((_d)->data, (_d)->nr, _pos, (_item)); \
  93         _ret;                                                           \
  94 })
  95
  96 #define darray_remove_items(_d, _pos, _nr_to_remove)                    \
  97         array_remove_items((_d)->data, (_d)->nr, (_pos) - (_d)->data, _nr_to_remove)
  98
  99 #define darray_remove_item(_d, _pos)                                    \
 100         darray_remove_items(_d, _pos, 1)
 101
 102 /* Iteration: */
 103
 104 #define __darray_for_each(_d, _i)                                       \
 105         for ((_i) = (_d).data; _i < (_d).data + (_d).nr; _i++)
 106
 107 #define darray_for_each(_d, _i)                                         \
 108         for (typeof(&(_d).data[0]) _i = (_d).data; _i < (_d).data + (_d).nr; _i++)
 109
 110 #define darray_for_each_reverse(_d, _i)                                 \
 111         for (typeof(&(_d).data[0]) _i = (_d).data + (_d).nr - 1; _i >= (_d).data; --_i)
 112
 113 #define darray_init(_d)                                                 \
 114 do {                                                                    \
 115         (_d)->nr = 0;                                                   \
 116         (_d)->size = ARRAY_SIZE((_d)->preallocated);                    \
 117         (_d)->data = (_d)->size ? (_d)->preallocated : NULL;            \
 118 } while (0)
 119
 120 #define darray_exit(_d)                                                 \
 121 do {                                                                    \
 122         if (!ARRAY_SIZE((_d)->preallocated) ||                          \
 123             (_d)->data != (_d)->preallocated)                           \
 124                 kvfree((_d)->data);                                     \
 125         darray_init(_d);                                                \
 126 } while (0)
 127
 128 #endif /* _LINUX_DARRAY_H */