diff options
Diffstat (limited to 'include/linux/bitmap.h')
| -rw-r--r-- | include/linux/bitmap.h | 27 |
1 files changed, 24 insertions, 3 deletions
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index e9b0b9ab07e5..3b77588a9360 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -266,9 +266,12 @@ static inline int bitmap_equal(const unsigned long *src1, const unsigned long *src2, unsigned int nbits) { if (small_const_nbits(nbits)) - return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); - else - return __bitmap_equal(src1, src2, nbits); + return !((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); +#ifdef CONFIG_S390 + if (__builtin_constant_p(nbits) && (nbits % BITS_PER_LONG) == 0) + return !memcmp(src1, src2, nbits / 8); +#endif + return __bitmap_equal(src1, src2, nbits); } static inline int bitmap_intersects(const unsigned long *src1, @@ -336,6 +339,24 @@ static inline int bitmap_parse(const char *buf, unsigned int buflen, return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits); } +/* + * bitmap_from_u64 - Check and swap words within u64. + * @mask: source bitmap + * @dst: destination bitmap + * + * In 32-bit Big Endian kernel, when using (u32 *)(&val)[*] + * to read u64 mask, we will get the wrong word. + * That is "(u32 *)(&val)[0]" gets the upper 32 bits, + * but we expect the lower 32-bits of u64. + */ +static inline void bitmap_from_u64(unsigned long *dst, u64 mask) +{ + dst[0] = mask & ULONG_MAX; + + if (sizeof(mask) > sizeof(unsigned long)) + dst[1] = mask >> 32; +} + #endif /* __ASSEMBLY__ */ #endif /* __LINUX_BITMAP_H */ |