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-rw-r--r--lib/bitmap.c137
1 files changed, 53 insertions, 84 deletions
diff --git a/lib/bitmap.c b/lib/bitmap.c
index d8f0c094b18e..9e498c77ed0e 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