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-rw-r--r--arch/arm/include/asm/bitops.h151
1 files changed, 151 insertions, 0 deletions
diff --git a/arch/arm/include/asm/bitops.h b/arch/arm/include/asm/bitops.h
new file mode 100644
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+++ b/arch/arm/include/asm/bitops.h
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+/*
+ * Copyright 1995, Russell King.
+ * Various bits and pieces copyrights include:
+ * Linus Torvalds (test_bit).
+ *
+ * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
+ *
+ * Please note that the code in this file should never be included
+ * from user space. Many of these are not implemented in assembler
+ * since they would be too costly. Also, they require priviledged
+ * instructions (which are not available from user mode) to ensure
+ * that they are atomic.
+ */
+
+#ifndef __ASM_ARM_BITOPS_H
+#define __ASM_ARM_BITOPS_H
+
+#ifdef __KERNEL__
+
+#include <asm/proc/system.h>
+
+#define smp_mb__before_clear_bit() do { } while (0)
+#define smp_mb__after_clear_bit() do { } while (0)
+
+/*
+ * Function prototypes to keep gcc -Wall happy.
+ */
+extern void set_bit(int nr, volatile void * addr);
+
+extern void clear_bit(int nr, volatile void * addr);
+
+extern void change_bit(int nr, volatile void * addr);
+
+static inline void __change_bit(int nr, volatile void *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+
+ *p ^= mask;
+}
+
+static inline int __test_and_set_bit(int nr, volatile void *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ unsigned long old = *p;
+
+ *p = old | mask;
+ return (old & mask) != 0;
+}
+
+static inline int test_and_set_bit(int nr, volatile void * addr)
+{
+ unsigned long flags;
+ int out;
+
+ local_irq_save(flags);
+ out = __test_and_set_bit(nr, addr);
+ local_irq_restore(flags);
+
+ return out;
+}
+
+static inline int __test_and_clear_bit(int nr, volatile void *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ unsigned long old = *p;
+
+ *p = old & ~mask;
+ return (old & mask) != 0;
+}
+
+static inline int test_and_clear_bit(int nr, volatile void * addr)
+{
+ unsigned long flags;
+ int out;
+
+ local_irq_save(flags);
+ out = __test_and_clear_bit(nr, addr);
+ local_irq_restore(flags);
+
+ return out;
+}
+
+extern int test_and_change_bit(int nr, volatile void * addr);
+
+static inline int __test_and_change_bit(int nr, volatile void *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ unsigned long old = *p;
+
+ *p = old ^ mask;
+ return (old & mask) != 0;
+}
+
+extern int find_first_zero_bit(void * addr, unsigned size);
+extern int find_next_zero_bit(void * addr, int size, int offset);
+
+/*
+ * This routine doesn't need to be atomic.
+ */
+static inline int test_bit(int nr, const void * addr)
+{
+ return ((unsigned char *) addr)[nr >> 3] & (1U << (nr & 7));
+}
+
+/*
+ * ffz = Find First Zero in word. Undefined if no zero exists,
+ * so code should check against ~0UL first..
+ */
+static inline unsigned long ffz(unsigned long word)
+{
+ int k;
+
+ word = ~word;
+ k = 31;
+ if (word & 0x0000ffff) { k -= 16; word <<= 16; }
+ if (word & 0x00ff0000) { k -= 8; word <<= 8; }
+ if (word & 0x0f000000) { k -= 4; word <<= 4; }
+ if (word & 0x30000000) { k -= 2; word <<= 2; }
+ if (word & 0x40000000) { k -= 1; }
+ return k;
+}
+
+/*
+ * hweightN: returns the hamming weight (i.e. the number
+ * of bits set) of a N-bit word
+ */
+
+#define hweight32(x) generic_hweight32(x)
+#define hweight16(x) generic_hweight16(x)
+#define hweight8(x) generic_hweight8(x)
+
+#define ext2_set_bit test_and_set_bit
+#define ext2_clear_bit test_and_clear_bit
+#define ext2_test_bit test_bit
+#define ext2_find_first_zero_bit find_first_zero_bit
+#define ext2_find_next_zero_bit find_next_zero_bit
+
+/* Bitmap functions for the minix filesystem. */
+#define minix_test_and_set_bit(nr,addr) test_and_set_bit(nr,addr)
+#define minix_set_bit(nr,addr) set_bit(nr,addr)
+#define minix_test_and_clear_bit(nr,addr) test_and_clear_bit(nr,addr)
+#define minix_test_bit(nr,addr) test_bit(nr,addr)
+#define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size)
+
+#endif /* __KERNEL__ */
+
+#endif /* _ARM_BITOPS_H */