diff options
Diffstat (limited to 'include/linux/bitmap.h')
| -rw-r--r-- | include/linux/bitmap.h | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 3489253e38fc..dac9dff90350 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -66,6 +66,8 @@ * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region * bitmap_from_u32array(dst, nbits, buf, nwords) *dst = *buf (nwords 32b words) * bitmap_to_u32array(buf, nwords, src, nbits) *buf = *dst (nwords 32b words) + * bitmap_from_arr32(dst, buf, nbits) Copy nbits from u32[] buf to dst + * bitmap_to_arr32(buf, src, nbits) Copy nbits from buf to u32[] dst * */ @@ -228,6 +230,35 @@ static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, } } +/* + * Copy bitmap and clear tail bits in last word. + */ +static inline void bitmap_copy_clear_tail(unsigned long *dst, + const unsigned long *src, unsigned int nbits) +{ + bitmap_copy(dst, src, nbits); + if (nbits % BITS_PER_LONG) + dst[nbits / BITS_PER_LONG] &= BITMAP_LAST_WORD_MASK(nbits); +} + +/* + * On 32-bit systems bitmaps are represented as u32 arrays internally, and + * therefore conversion is not needed when copying data from/to arrays of u32. + */ +#if BITS_PER_LONG == 64 +extern void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, + unsigned int nbits); +extern void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, + unsigned int nbits); +#else +#define bitmap_from_arr32(bitmap, buf, nbits) \ + bitmap_copy_clear_tail((unsigned long *) (bitmap), \ + (const unsigned long *) (buf), (nbits)) +#define bitmap_to_arr32(buf, bitmap, nbits) \ + bitmap_copy_clear_tail((unsigned long *) (buf), \ + (const unsigned long *) (bitmap), (nbits)) +#endif + static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, const unsigned long *src2, unsigned int nbits) { |