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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-x86_64/bitops.h
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-x86_64/bitops.h')
-rw-r--r--include/asm-x86_64/bitops.h418
1 files changed, 418 insertions, 0 deletions
diff --git a/include/asm-x86_64/bitops.h b/include/asm-x86_64/bitops.h
new file mode 100644
index 000000000000..5dd7727c756b
--- /dev/null
+++ b/include/asm-x86_64/bitops.h
@@ -0,0 +1,418 @@
+#ifndef _X86_64_BITOPS_H
+#define _X86_64_BITOPS_H
+
+/*
+ * Copyright 1992, Linus Torvalds.
+ */
+
+#include <linux/config.h>
+
+#ifdef CONFIG_SMP
+#define LOCK_PREFIX "lock ; "
+#else
+#define LOCK_PREFIX ""
+#endif
+
+#define ADDR (*(volatile long *) addr)
+
+/**
+ * set_bit - Atomically set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This function is atomic and may not be reordered. See __set_bit()
+ * if you do not require the atomic guarantees.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static __inline__ void set_bit(int nr, volatile void * addr)
+{
+ __asm__ __volatile__( LOCK_PREFIX
+ "btsl %1,%0"
+ :"=m" (ADDR)
+ :"dIr" (nr) : "memory");
+}
+
+/**
+ * __set_bit - Set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * Unlike set_bit(), this function is non-atomic and may be reordered.
+ * If it's called on the same region of memory simultaneously, the effect
+ * may be that only one operation succeeds.
+ */
+static __inline__ void __set_bit(int nr, volatile void * addr)
+{
+ __asm__ volatile(
+ "btsl %1,%0"
+ :"=m" (ADDR)
+ :"dIr" (nr) : "memory");
+}
+
+/**
+ * clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * clear_bit() is atomic and may not be reordered. However, it does
+ * not contain a memory barrier, so if it is used for locking purposes,
+ * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
+ * in order to ensure changes are visible on other processors.
+ */
+static __inline__ void clear_bit(int nr, volatile void * addr)
+{
+ __asm__ __volatile__( LOCK_PREFIX
+ "btrl %1,%0"
+ :"=m" (ADDR)
+ :"dIr" (nr));
+}
+
+static __inline__ void __clear_bit(int nr, volatile void * addr)
+{
+ __asm__ __volatile__(
+ "btrl %1,%0"
+ :"=m" (ADDR)
+ :"dIr" (nr));
+}
+
+#define smp_mb__before_clear_bit() barrier()
+#define smp_mb__after_clear_bit() barrier()
+
+/**
+ * __change_bit - Toggle a bit in memory
+ * @nr: the bit to change
+ * @addr: the address to start counting from
+ *
+ * Unlike change_bit(), this function is non-atomic and may be reordered.
+ * If it's called on the same region of memory simultaneously, the effect
+ * may be that only one operation succeeds.
+ */
+static __inline__ void __change_bit(int nr, volatile void * addr)
+{
+ __asm__ __volatile__(
+ "btcl %1,%0"
+ :"=m" (ADDR)
+ :"dIr" (nr));
+}
+
+/**
+ * change_bit - Toggle a bit in memory
+ * @nr: Bit to change
+ * @addr: Address to start counting from
+ *
+ * change_bit() is atomic and may not be reordered.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static __inline__ void change_bit(int nr, volatile void * addr)
+{
+ __asm__ __volatile__( LOCK_PREFIX
+ "btcl %1,%0"
+ :"=m" (ADDR)
+ :"dIr" (nr));
+}
+
+/**
+ * test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static __inline__ int test_and_set_bit(int nr, volatile void * addr)
+{
+ int oldbit;
+
+ __asm__ __volatile__( LOCK_PREFIX
+ "btsl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit),"=m" (ADDR)
+ :"dIr" (nr) : "memory");
+ return oldbit;
+}
+
+/**
+ * __test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
+ * If two examples of this operation race, one can appear to succeed
+ * but actually fail. You must protect multiple accesses with a lock.
+ */
+static __inline__ int __test_and_set_bit(int nr, volatile void * addr)
+{
+ int oldbit;
+
+ __asm__(
+ "btsl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit),"=m" (ADDR)
+ :"dIr" (nr));
+ return oldbit;
+}
+
+/**
+ * test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static __inline__ int test_and_clear_bit(int nr, volatile void * addr)
+{
+ int oldbit;
+
+ __asm__ __volatile__( LOCK_PREFIX
+ "btrl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit),"=m" (ADDR)
+ :"dIr" (nr) : "memory");
+ return oldbit;
+}
+
+/**
+ * __test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
+ * If two examples of this operation race, one can appear to succeed
+ * but actually fail. You must protect multiple accesses with a lock.
+ */
+static __inline__ int __test_and_clear_bit(int nr, volatile void * addr)
+{
+ int oldbit;
+
+ __asm__(
+ "btrl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit),"=m" (ADDR)
+ :"dIr" (nr));
+ return oldbit;
+}
+
+/* WARNING: non atomic and it can be reordered! */
+static __inline__ int __test_and_change_bit(int nr, volatile void * addr)
+{
+ int oldbit;
+
+ __asm__ __volatile__(
+ "btcl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit),"=m" (ADDR)
+ :"dIr" (nr) : "memory");
+ return oldbit;
+}
+
+/**
+ * test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static __inline__ int test_and_change_bit(int nr, volatile void * addr)
+{
+ int oldbit;
+
+ __asm__ __volatile__( LOCK_PREFIX
+ "btcl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit),"=m" (ADDR)
+ :"dIr" (nr) : "memory");
+ return oldbit;
+}
+
+#if 0 /* Fool kernel-doc since it doesn't do macros yet */
+/**
+ * test_bit - Determine whether a bit is set
+ * @nr: bit number to test
+ * @addr: Address to start counting from
+ */
+static int test_bit(int nr, const volatile void * addr);
+#endif
+
+static __inline__ int constant_test_bit(int nr, const volatile void * addr)
+{
+ return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0;
+}
+
+static __inline__ int variable_test_bit(int nr, volatile const void * addr)
+{
+ int oldbit;
+
+ __asm__ __volatile__(
+ "btl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit)
+ :"m" (ADDR),"dIr" (nr));
+ return oldbit;
+}
+
+#define test_bit(nr,addr) \
+(__builtin_constant_p(nr) ? \
+ constant_test_bit((nr),(addr)) : \
+ variable_test_bit((nr),(addr)))
+
+#undef ADDR
+
+extern long find_first_zero_bit(const unsigned long * addr, unsigned long size);
+extern long find_next_zero_bit (const unsigned long * addr, long size, long offset);
+extern long find_first_bit(const unsigned long * addr, unsigned long size);
+extern long find_next_bit(const unsigned long * addr, long size, long offset);
+
+/* return index of first bet set in val or max when no bit is set */
+static inline unsigned long __scanbit(unsigned long val, unsigned long max)
+{
+ asm("bsfq %1,%0 ; cmovz %2,%0" : "=&r" (val) : "r" (val), "r" (max));
+ return val;
+}
+
+#define find_first_bit(addr,size) \
+((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
+ (__scanbit(*(unsigned long *)addr,(size))) : \
+ find_first_bit(addr,size)))
+
+#define find_next_bit(addr,size,off) \
+((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
+ ((off) + (__scanbit((*(unsigned long *)addr) >> (off),(size)-(off)))) : \
+ find_next_bit(addr,size,off)))
+
+#define find_first_zero_bit(addr,size) \
+((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
+ (__scanbit(~*(unsigned long *)addr,(size))) : \
+ find_first_zero_bit(addr,size)))
+
+#define find_next_zero_bit(addr,size,off) \
+((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
+ ((off)+(__scanbit(~(((*(unsigned long *)addr)) >> (off)),(size)-(off)))) : \
+ find_next_zero_bit(addr,size,off)))
+
+/*
+ * Find string of zero bits in a bitmap. -1 when not found.
+ */
+extern unsigned long
+find_next_zero_string(unsigned long *bitmap, long start, long nbits, int len);
+
+static inline void set_bit_string(unsigned long *bitmap, unsigned long i,
+ int len)
+{
+ unsigned long end = i + len;
+ while (i < end) {
+ __set_bit(i, bitmap);
+ i++;
+ }
+}
+
+static inline void __clear_bit_string(unsigned long *bitmap, unsigned long i,
+ int len)
+{
+ unsigned long end = i + len;
+ while (i < end) {
+ __clear_bit(i, bitmap);
+ i++;
+ }
+}
+
+/**
+ * ffz - find first zero in word.
+ * @word: The word to search
+ *
+ * Undefined if no zero exists, so code should check against ~0UL first.
+ */
+static __inline__ unsigned long ffz(unsigned long word)
+{
+ __asm__("bsfq %1,%0"
+ :"=r" (word)
+ :"r" (~word));
+ return word;
+}
+
+/**
+ * __ffs - find first bit in word.
+ * @word: The word to search
+ *
+ * Undefined if no bit exists, so code should check against 0 first.
+ */
+static __inline__ unsigned long __ffs(unsigned long word)
+{
+ __asm__("bsfq %1,%0"
+ :"=r" (word)
+ :"rm" (word));
+ return word;
+}
+
+#ifdef __KERNEL__
+
+static inline int sched_find_first_bit(const unsigned long *b)
+{
+ if (b[0])
+ return __ffs(b[0]);
+ if (b[1])
+ return __ffs(b[1]) + 64;
+ if (b[2])
+ return __ffs(b[2]) + 128;
+}
+
+/**
+ * ffs - find first bit set
+ * @x: the word to search
+ *
+ * This is defined the same way as
+ * the libc and compiler builtin ffs routines, therefore
+ * differs in spirit from the above ffz (man ffs).
+ */
+static __inline__ int ffs(int x)
+{
+ int r;
+
+ __asm__("bsfl %1,%0\n\t"
+ "cmovzl %2,%0"
+ : "=r" (r) : "rm" (x), "r" (-1));
+ return r+1;
+}
+
+/**
+ * hweightN - returns the hamming weight of a N-bit word
+ * @x: the word to weigh
+ *
+ * The Hamming Weight of a number is the total number of bits set in it.
+ */
+
+#define hweight64(x) generic_hweight64(x)
+#define hweight32(x) generic_hweight32(x)
+#define hweight16(x) generic_hweight16(x)
+#define hweight8(x) generic_hweight8(x)
+
+#endif /* __KERNEL__ */
+
+#ifdef __KERNEL__
+
+#define ext2_set_bit(nr,addr) \
+ __test_and_set_bit((nr),(unsigned long*)addr)
+#define ext2_set_bit_atomic(lock,nr,addr) \
+ test_and_set_bit((nr),(unsigned long*)addr)
+#define ext2_clear_bit(nr, addr) \
+ __test_and_clear_bit((nr),(unsigned long*)addr)
+#define ext2_clear_bit_atomic(lock,nr,addr) \
+ test_and_clear_bit((nr),(unsigned long*)addr)
+#define ext2_test_bit(nr, addr) test_bit((nr),(unsigned long*)addr)
+#define ext2_find_first_zero_bit(addr, size) \
+ find_first_zero_bit((unsigned long*)addr, size)
+#define ext2_find_next_zero_bit(addr, size, off) \
+ find_next_zero_bit((unsigned long*)addr, size, off)
+
+/* Bitmap functions for the minix filesystem. */
+#define minix_test_and_set_bit(nr,addr) __test_and_set_bit(nr,(void*)addr)
+#define minix_set_bit(nr,addr) __set_bit(nr,(void*)addr)
+#define minix_test_and_clear_bit(nr,addr) __test_and_clear_bit(nr,(void*)addr)
+#define minix_test_bit(nr,addr) test_bit(nr,(void*)addr)
+#define minix_find_first_zero_bit(addr,size) \
+ find_first_zero_bit((void*)addr,size)
+
+/* find last set bit */
+#define fls(x) generic_fls(x)
+
+#define ARCH_HAS_ATOMIC_UNSIGNED 1
+
+#endif /* __KERNEL__ */
+
+#endif /* _X86_64_BITOPS_H */