Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/pci-2.6

[linux-2.6-omap-h63xx.git] / include / asm-ia64 / bitops.h

diff --git a/include/asm-ia64/bitops.h b/include/asm-ia64/bitops.h
index 2144f1a8ed6f7f89793858c9cab1d4f73b37be95..953d3df9dd22670f16fec92440a9dc18f5431593 100644 (file)
--- a/include/asm-ia64/bitops.h
+++ b/include/asm-ia64/bitops.h
@@ -9,6 +9,10 @@
  * 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/intrinsics.h>
@@ -118,27 +122,40 @@ clear_bit_unlock (int nr, volatile void *addr)
 }
 
 /**
- * __clear_bit_unlock - Non-atomically clear a bit with release
+ * __clear_bit_unlock - Non-atomically clears a bit in memory with release
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
  *
- * This is like clear_bit_unlock, but the implementation may use a non-atomic
- * store (this one uses an atomic, however).
+ * Similarly to clear_bit_unlock, the implementation uses a store
+ * with release semantics. See also __raw_spin_unlock().
  */
-#define __clear_bit_unlock clear_bit_unlock
+static __inline__ void
+__clear_bit_unlock(int nr, void *addr)
+{
+       __u32 * const m = (__u32 *) addr + (nr >> 5);
+       __u32 const new = *m & ~(1 << (nr & 31));
+
+       ia64_st4_rel_nta(m, new);
+}
 
 /**
  * __clear_bit - Clears a bit in memory (non-atomic version)
+ * @nr: the bit to clear
+ * @addr: the address to start counting from
+ *
+ * Unlike clear_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
 __clear_bit (int nr, volatile void *addr)
 {
-       volatile __u32 *p = (__u32 *) addr + (nr >> 5);
-       __u32 m = 1 << (nr & 31);
-       *p &= ~m;
+       *((__u32 *) addr + (nr >> 5)) &= ~(1 << (nr & 31));
 }
 
 /**
  * change_bit - Toggle a bit in memory
- * @nr: Bit to clear
+ * @nr: Bit to toggle
  * @addr: Address to start counting from
  *
  * change_bit() is atomic and may not be reordered.
@@ -163,7 +180,7 @@ change_bit (int nr, volatile void *addr)
 
 /**
  * __change_bit - Toggle a bit in memory
- * @nr: the bit to set
+ * @nr: the bit to toggle
  * @addr: the address to start counting from
  *
  * Unlike change_bit(), this function is non-atomic and may be reordered.
@@ -182,7 +199,7 @@ __change_bit (int nr, volatile void *addr)
  * @addr: Address to count from
  *
  * This operation is atomic and cannot be reordered.  
- * It also implies a memory barrier.
+ * It also implies the acquisition side of the memory barrier.
  */
 static __inline__ int
 test_and_set_bit (int nr, volatile void *addr)
@@ -232,11 +249,11 @@ __test_and_set_bit (int nr, volatile void *addr)
 
 /**
  * test_and_clear_bit - Clear a bit and return its old value
- * @nr: Bit to set
+ * @nr: Bit to clear
  * @addr: Address to count from
  *
  * This operation is atomic and cannot be reordered.  
- * It also implies a memory barrier.
+ * It also implies the acquisition side of the memory barrier.
  */
 static __inline__ int
 test_and_clear_bit (int nr, volatile void *addr)
@@ -257,7 +274,7 @@ test_and_clear_bit (int nr, volatile void *addr)
 
 /**
  * __test_and_clear_bit - Clear a bit and return its old value
- * @nr: Bit to set
+ * @nr: Bit to clear
  * @addr: Address to count from
  *
  * This operation is non-atomic and can be reordered.  
@@ -277,11 +294,11 @@ __test_and_clear_bit(int nr, volatile void * addr)
 
 /**
  * test_and_change_bit - Change a bit and return its old value
- * @nr: Bit to set
+ * @nr: Bit to change
  * @addr: Address to count from
  *
  * This operation is atomic and cannot be reordered.  
- * It also implies a memory barrier.
+ * It also implies the acquisition side of the memory barrier.
  */
 static __inline__ int
 test_and_change_bit (int nr, volatile void *addr)
@@ -300,8 +317,12 @@ test_and_change_bit (int nr, volatile void *addr)
        return (old & bit) != 0;
 }
 
-/*
- * WARNING: non atomic version.
+/**
+ * __test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
  */
 static __inline__ int
 __test_and_change_bit (int nr, void *addr)