* Copyright (C) 1998-2003 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
*
- * 02/06/02 find_next_bit() and find_first_bit() added from Erich Focht's ia64 O(1)
- * scheduler patch
+ * 02/06/02 find_next_bit() and find_first_bit() added from Erich Focht's ia64
+ * O(1) scheduler patch
*/
+#ifndef _LINUX_BITOPS_H
+#error only <linux/bitops.h> can be included directly
+#endif
+
#include <linux/compiler.h>
#include <linux/types.h>
-#include <asm/bitops.h>
#include <asm/intrinsics.h>
/**
* restricted to acting on a single-word quantity.
*
* The address must be (at least) "long" aligned.
- * Note that there are driver (e.g., eepro100) which use these operations to operate on
- * hw-defined data-structures, so we can't easily change these operations to force a
- * bigger alignment.
+ * Note that there are driver (e.g., eepro100) which use these operations to
+ * operate on hw-defined data-structures, so we can't easily change these
+ * operations to force a bigger alignment.
*
* bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
*/
}
/**
+ * clear_bit_unlock - Clears a bit in memory with release
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * clear_bit_unlock() is atomic and may not be reordered. It does
+ * contain a memory barrier suitable for unlock type operations.
+ */
+static __inline__ void
+clear_bit_unlock (int nr, volatile void *addr)
+{
+ __u32 mask, old, new;
+ volatile __u32 *m;
+ CMPXCHG_BUGCHECK_DECL
+
+ m = (volatile __u32 *) addr + (nr >> 5);
+ mask = ~(1 << (nr & 31));
+ do {
+ CMPXCHG_BUGCHECK(m);
+ old = *m;
+ new = old & mask;
+ } while (cmpxchg_rel(m, old, new) != old);
+}
+
+/**
+ * __clear_bit_unlock - Non-atomically clear a bit with release
+ *
+ * This is like clear_bit_unlock, but the implementation uses a store
+ * with release semantics. See also __raw_spin_unlock().
+ */
+static __inline__ void
+__clear_bit_unlock(int nr, volatile void *addr)
+{
+ __u32 mask, new;
+ volatile __u32 *m;
+
+ m = (volatile __u32 *)addr + (nr >> 5);
+ mask = ~(1 << (nr & 31));
+ new = *m & mask;
+ barrier();
+ ia64_st4_rel_nta(m, new);
+}
+
+/**
* __clear_bit - Clears a bit in memory (non-atomic version)
*/
static __inline__ void
}
/**
+ * test_and_set_bit_lock - Set a bit and return its old value for lock
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This is the same as test_and_set_bit on ia64
+ */
+#define test_and_set_bit_lock test_and_set_bit
+
+/**
* __test_and_set_bit - Set a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
* ffz - find the first zero bit in a long word
* @x: The long word to find the bit in
*
- * Returns the bit-number (0..63) of the first (least significant) zero bit. Undefined if
- * no zero exists, so code should check against ~0UL first...
+ * Returns the bit-number (0..63) of the first (least significant) zero bit.
+ * Undefined if no zero exists, so code should check against ~0UL first...
*/
static inline unsigned long
ffz (unsigned long x)
return ia64_popcnt(x);
}
+#include <asm-generic/bitops/fls64.h>
+
/*
- * ffs: find first bit set. This is defined the same way as the libc and compiler builtin
- * ffs routines, therefore differs in spirit from the above ffz (man ffs): it operates on
- * "int" values only and the result value is the bit number + 1. ffs(0) is defined to
- * return zero.
+ * ffs: find first bit set. This is defined the same way as the libc and
+ * compiler builtin ffs routines, therefore differs in spirit from the above
+ * ffz (man ffs): it operates on "int" values only and the result value is the
+ * bit number + 1. ffs(0) is defined to return zero.
*/
#define ffs(x) __builtin_ffs(x)
#endif /* __KERNEL__ */
-extern int __find_next_zero_bit (const void *addr, unsigned long size,
- unsigned long offset);
-extern int __find_next_bit(const void *addr, unsigned long size,
- unsigned long offset);
-
-#define find_next_zero_bit(addr, size, offset) \
- __find_next_zero_bit((addr), (size), (offset))
-#define find_next_bit(addr, size, offset) \
- __find_next_bit((addr), (size), (offset))
-
-/*
- * The optimizer actually does good code for this case..
- */
-#define find_first_zero_bit(addr, size) find_next_zero_bit((addr), (size), 0)
-
-#define find_first_bit(addr, size) find_next_bit((addr), (size), 0)
+#include <asm-generic/bitops/find.h>
#ifdef __KERNEL__
-#define __clear_bit(nr, addr) clear_bit(nr, addr)
+#include <asm-generic/bitops/ext2-non-atomic.h>
-#define ext2_set_bit test_and_set_bit
#define ext2_set_bit_atomic(l,n,a) test_and_set_bit(n,a)
-#define ext2_clear_bit test_and_clear_bit
#define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a)
-#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)
-static inline int
-sched_find_first_bit (unsigned long *b)
-{
- if (unlikely(b[0]))
- return __ffs(b[0]);
- if (unlikely(b[1]))
- return 64 + __ffs(b[1]);
- return __ffs(b[2]) + 128;
-}
+#include <asm-generic/bitops/minix.h>
+#include <asm-generic/bitops/sched.h>
#endif /* __KERNEL__ */
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