diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/idr.h | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/include/linux/idr.h b/include/linux/idr.h index 826803449db7..915572fa030b 100644 --- a/include/linux/idr.h +++ b/include/linux/idr.h @@ -83,4 +83,33 @@ void idr_remove(struct idr *idp, int id); void idr_destroy(struct idr *idp); void idr_init(struct idr *idp); + +/* + * IDA - IDR based id allocator, use when translation from id to + * pointer isn't necessary. + */ +#define IDA_CHUNK_SIZE 128 /* 128 bytes per chunk */ +#define IDA_BITMAP_LONGS (128 / sizeof(long) - 1) +#define IDA_BITMAP_BITS (IDA_BITMAP_LONGS * sizeof(long) * 8) + +struct ida_bitmap { + long nr_busy; + unsigned long bitmap[IDA_BITMAP_LONGS]; +}; + +struct ida { + struct idr idr; + struct ida_bitmap *free_bitmap; +}; + +#define IDA_INIT(name) { .idr = IDR_INIT(name), .free_bitmap = NULL, } +#define DEFINE_IDA(name) struct ida name = IDA_INIT(name) + +int ida_pre_get(struct ida *ida, gfp_t gfp_mask); +int ida_get_new_above(struct ida *ida, int starting_id, int *p_id); +int ida_get_new(struct ida *ida, int *p_id); +void ida_remove(struct ida *ida, int id); +void ida_destroy(struct ida *ida); +void ida_init(struct ida *ida); + #endif /* __IDR_H__ */ |