Make bitmask 'and' operators return a result code

[pandora-kernel.git] / include / linux / bitmap.h

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index a08c33a..756d78b 100644 (file)
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -94,13 +94,13 @@ extern void __bitmap_shift_right(unsigned long *dst,
                         const unsigned long *src, int shift, int bits);
 extern void __bitmap_shift_left(unsigned long *dst,
                         const unsigned long *src, int shift, int bits);
-extern void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
+extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
                        const unsigned long *bitmap2, int bits);
 extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
                        const unsigned long *bitmap2, int bits);
 extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
                        const unsigned long *bitmap2, int bits);
-extern void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
+extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
                        const unsigned long *bitmap2, int bits);
 extern int __bitmap_intersects(const unsigned long *bitmap1,
                        const unsigned long *bitmap2, int bits);
@@ -137,9 +137,12 @@ extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits);
                (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL               \
 )
 
+#define small_const_nbits(nbits) \
+       (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
+
 static inline void bitmap_zero(unsigned long *dst, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                *dst = 0UL;
        else {
                int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
@@ -150,7 +153,7 @@ static inline void bitmap_zero(unsigned long *dst, int nbits)
 static inline void bitmap_fill(unsigned long *dst, int nbits)
 {
        size_t nlongs = BITS_TO_LONGS(nbits);
-       if (nlongs > 1) {
+       if (!small_const_nbits(nbits)) {
                int len = (nlongs - 1) * sizeof(unsigned long);
                memset(dst, 0xff,  len);
        }
@@ -160,7 +163,7 @@ static inline void bitmap_fill(unsigned long *dst, int nbits)
 static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
                        int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                *dst = *src;
        else {
                int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
@@ -168,19 +171,18 @@ static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
        }
 }
 
-static inline void bitmap_and(unsigned long *dst, const unsigned long *src1,
+static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
                        const unsigned long *src2, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
-               *dst = *src1 & *src2;
-       else
-               __bitmap_and(dst, src1, src2, nbits);
+       if (small_const_nbits(nbits))
+               return (*dst = *src1 & *src2) != 0;
+       return __bitmap_and(dst, src1, src2, nbits);
 }
 
 static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
                        const unsigned long *src2, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                *dst = *src1 | *src2;
        else
                __bitmap_or(dst, src1, src2, nbits);
@@ -189,25 +191,24 @@ static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
 static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
                        const unsigned long *src2, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                *dst = *src1 ^ *src2;
        else
                __bitmap_xor(dst, src1, src2, nbits);
 }
 
-static inline void bitmap_andnot(unsigned long *dst, const unsigned long *src1,
+static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1,
                        const unsigned long *src2, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
-               *dst = *src1 & ~(*src2);
-       else
-               __bitmap_andnot(dst, src1, src2, nbits);
+       if (small_const_nbits(nbits))
+               return (*dst = *src1 & ~(*src2)) != 0;
+       return __bitmap_andnot(dst, src1, src2, nbits);
 }
 
 static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
                        int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits);
        else
                __bitmap_complement(dst, src, nbits);
@@ -216,7 +217,7 @@ static inline void bitmap_complement(unsigned long *dst, const unsigned long *sr
 static inline int bitmap_equal(const unsigned long *src1,
                        const unsigned long *src2, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
        else
                return __bitmap_equal(src1, src2, nbits);
@@ -225,7 +226,7 @@ static inline int bitmap_equal(const unsigned long *src1,
 static inline int bitmap_intersects(const unsigned long *src1,
                        const unsigned long *src2, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
        else
                return __bitmap_intersects(src1, src2, nbits);
@@ -234,7 +235,7 @@ static inline int bitmap_intersects(const unsigned long *src1,
 static inline int bitmap_subset(const unsigned long *src1,
                        const unsigned long *src2, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
        else
                return __bitmap_subset(src1, src2, nbits);
@@ -242,7 +243,7 @@ static inline int bitmap_subset(const unsigned long *src1,
 
 static inline int bitmap_empty(const unsigned long *src, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
        else
                return __bitmap_empty(src, nbits);
@@ -250,7 +251,7 @@ static inline int bitmap_empty(const unsigned long *src, int nbits)
 
 static inline int bitmap_full(const unsigned long *src, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
        else
                return __bitmap_full(src, nbits);
@@ -258,7 +259,7 @@ static inline int bitmap_full(const unsigned long *src, int nbits)
 
 static inline int bitmap_weight(const unsigned long *src, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
        return __bitmap_weight(src, nbits);
 }
@@ -266,7 +267,7 @@ static inline int bitmap_weight(const unsigned long *src, int nbits)
 static inline void bitmap_shift_right(unsigned long *dst,
                        const unsigned long *src, int n, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                *dst = *src >> n;
        else
                __bitmap_shift_right(dst, src, n, nbits);
@@ -275,7 +276,7 @@ static inline void bitmap_shift_right(unsigned long *dst,
 static inline void bitmap_shift_left(unsigned long *dst,
                        const unsigned long *src, int n, int nbits)
 {
-       if (nbits <= BITS_PER_LONG)
+       if (small_const_nbits(nbits))
                *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
        else
                __bitmap_shift_left(dst, src, n, nbits);