diff options
Diffstat (limited to 'lib/bitmap.c')
-rw-r--r-- | lib/bitmap.c | 137 |
1 files changed, 53 insertions, 84 deletions
diff --git a/lib/bitmap.c b/lib/bitmap.c index d8f0c09..9e498c7 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -1106,111 +1106,80 @@ int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order) EXPORT_SYMBOL(bitmap_allocate_region); /** - * bitmap_from_u32array - copy the contents of a u32 array of bits to bitmap - * @bitmap: array of unsigned longs, the destination bitmap, non NULL - * @nbits: number of bits in @bitmap - * @buf: array of u32 (in host byte order), the source bitmap, non NULL - * @nwords: number of u32 words in @buf - * - * copy min(nbits, 32*nwords) bits from @buf to @bitmap, remaining - * bits between nword and nbits in @bitmap (if any) are cleared. In - * last word of @bitmap, the bits beyond nbits (if any) are kept - * unchanged. + * bitmap_copy_le - copy a bitmap, putting the bits into little-endian order. + * @dst: destination buffer + * @src: bitmap to copy + * @nbits: number of bits in the bitmap * - * Return the number of bits effectively copied. + * Require nbits % BITS_PER_LONG == 0. */ -unsigned int -bitmap_from_u32array(unsigned long *bitmap, unsigned int nbits, - const u32 *buf, unsigned int nwords) +#ifdef __BIG_ENDIAN +void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits) { - unsigned int dst_idx, src_idx; - - for (src_idx = dst_idx = 0; dst_idx < BITS_TO_LONGS(nbits); ++dst_idx) { - unsigned long part = 0; - - if (src_idx < nwords) - part = buf[src_idx++]; - -#if BITS_PER_LONG == 64 - if (src_idx < nwords) - part |= ((unsigned long) buf[src_idx++]) << 32; -#endif - - if (dst_idx < nbits/BITS_PER_LONG) - bitmap[dst_idx] = part; - else { - unsigned long mask = BITMAP_LAST_WORD_MASK(nbits); + unsigned int i; - bitmap[dst_idx] = (bitmap[dst_idx] & ~mask) - | (part & mask); - } + for (i = 0; i < nbits/BITS_PER_LONG; i++) { + if (BITS_PER_LONG == 64) + dst[i] = cpu_to_le64(src[i]); + else + dst[i] = cpu_to_le32(src[i]); } - - return min_t(unsigned int, nbits, 32*nwords); } -EXPORT_SYMBOL(bitmap_from_u32array); +EXPORT_SYMBOL(bitmap_copy_le); +#endif +#if BITS_PER_LONG == 64 /** - * bitmap_to_u32array - copy the contents of bitmap to a u32 array of bits - * @buf: array of u32 (in host byte order), the dest bitmap, non NULL - * @nwords: number of u32 words in @buf - * @bitmap: array of unsigned longs, the source bitmap, non NULL + * bitmap_from_arr32 - copy the contents of u32 array of bits to bitmap + * @bitmap: array of unsigned longs, the destination bitmap + * @buf: array of u32 (in host byte order), the source bitmap * @nbits: number of bits in @bitmap - * - * copy min(nbits, 32*nwords) bits from @bitmap to @buf. Remaining - * bits after nbits in @buf (if any) are cleared. - * - * Return the number of bits effectively copied. */ -unsigned int -bitmap_to_u32array(u32 *buf, unsigned int nwords, - const unsigned long *bitmap, unsigned int nbits) +void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, + unsigned int nbits) { - unsigned int dst_idx = 0, src_idx = 0; - - while (dst_idx < nwords) { - unsigned long part = 0; - - if (src_idx < BITS_TO_LONGS(nbits)) { - part = bitmap[src_idx]; - if (src_idx >= nbits/BITS_PER_LONG) - part &= BITMAP_LAST_WORD_MASK(nbits); - src_idx++; - } + unsigned int i, halfwords; - buf[dst_idx++] = part & 0xffffffffUL; + if (!nbits) + return; -#if BITS_PER_LONG == 64 - if (dst_idx < nwords) { - part >>= 32; - buf[dst_idx++] = part & 0xffffffffUL; - } -#endif + halfwords = DIV_ROUND_UP(nbits, 32); + for (i = 0; i < halfwords; i++) { + bitmap[i/2] = (unsigned long) buf[i]; + if (++i < halfwords) + bitmap[i/2] |= ((unsigned long) buf[i]) << 32; } - return min_t(unsigned int, nbits, 32*nwords); + /* Clear tail bits in last word beyond nbits. */ + if (nbits % BITS_PER_LONG) + bitmap[(halfwords - 1) / 2] &= BITMAP_LAST_WORD_MASK(nbits); } -EXPORT_SYMBOL(bitmap_to_u32array); +EXPORT_SYMBOL(bitmap_from_arr32); /** - * bitmap_copy_le - copy a bitmap, putting the bits into little-endian order. - * @dst: destination buffer - * @src: bitmap to copy - * @nbits: number of bits in the bitmap - * - * Require nbits % BITS_PER_LONG == 0. + * bitmap_to_arr32 - copy the contents of bitmap to a u32 array of bits + * @buf: array of u32 (in host byte order), the dest bitmap + * @bitmap: array of unsigned longs, the source bitmap + * @nbits: number of bits in @bitmap */ -#ifdef __BIG_ENDIAN -void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits) +void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, unsigned int nbits) { - unsigned int i; + unsigned int i, halfwords; - for (i = 0; i < nbits/BITS_PER_LONG; i++) { - if (BITS_PER_LONG == 64) - dst[i] = cpu_to_le64(src[i]); - else - dst[i] = cpu_to_le32(src[i]); + if (!nbits) + return; + + halfwords = DIV_ROUND_UP(nbits, 32); + for (i = 0; i < halfwords; i++) { + buf[i] = (u32) (bitmap[i/2] & UINT_MAX); + if (++i < halfwords) + buf[i] = (u32) (bitmap[i/2] >> 32); } + + /* Clear tail bits in last element of array beyond nbits. */ + if (nbits % BITS_PER_LONG) + buf[halfwords - 1] &= (u32) (UINT_MAX >> ((-nbits) & 31)); } -EXPORT_SYMBOL(bitmap_copy_le); +EXPORT_SYMBOL(bitmap_to_arr32); + #endif |