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-rw-r--r--xenolinux-2.4.21-pre4-sparse/include/asm-xeno/atomic.h204
1 files changed, 204 insertions, 0 deletions
diff --git a/xenolinux-2.4.21-pre4-sparse/include/asm-xeno/atomic.h b/xenolinux-2.4.21-pre4-sparse/include/asm-xeno/atomic.h
new file mode 100644
index 0000000000..b356b37394
--- /dev/null
+++ b/xenolinux-2.4.21-pre4-sparse/include/asm-xeno/atomic.h
@@ -0,0 +1,204 @@
+#ifndef __ARCH_I386_ATOMIC__
+#define __ARCH_I386_ATOMIC__
+
+#include <linux/config.h>
+
+/*
+ * Atomic operations that C can't guarantee us. Useful for
+ * resource counting etc..
+ */
+
+#ifdef CONFIG_SMP
+#define LOCK "lock ; "
+#else
+#define LOCK ""
+#endif
+
+/*
+ * Make sure gcc doesn't try to be clever and move things around
+ * on us. We need to use _exactly_ the address the user gave us,
+ * not some alias that contains the same information.
+ */
+typedef struct { volatile int counter; } atomic_t;
+
+#define ATOMIC_INIT(i) { (i) }
+
+/**
+ * atomic_read - read atomic variable
+ * @v: pointer of type atomic_t
+ *
+ * Atomically reads the value of @v. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+#define atomic_read(v) ((v)->counter)
+
+/**
+ * atomic_set - set atomic variable
+ * @v: pointer of type atomic_t
+ * @i: required value
+ *
+ * Atomically sets the value of @v to @i. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+#define atomic_set(v,i) (((v)->counter) = (i))
+
+/**
+ * atomic_add - add integer to atomic variable
+ * @i: integer value to add
+ * @v: pointer of type atomic_t
+ *
+ * Atomically adds @i to @v. Note that the guaranteed useful range
+ * of an atomic_t is only 24 bits.
+ */
+static __inline__ void atomic_add(int i, atomic_t *v)
+{
+ __asm__ __volatile__(
+ LOCK "addl %1,%0"
+ :"=m" (v->counter)
+ :"ir" (i), "m" (v->counter));
+}
+
+/**
+ * atomic_sub - subtract the atomic variable
+ * @i: integer value to subtract
+ * @v: pointer of type atomic_t
+ *
+ * Atomically subtracts @i from @v. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+static __inline__ void atomic_sub(int i, atomic_t *v)
+{
+ __asm__ __volatile__(
+ LOCK "subl %1,%0"
+ :"=m" (v->counter)
+ :"ir" (i), "m" (v->counter));
+}
+
+/**
+ * atomic_sub_and_test - subtract value from variable and test result
+ * @i: integer value to subtract
+ * @v: pointer of type atomic_t
+ *
+ * Atomically subtracts @i from @v and returns
+ * true if the result is zero, or false for all
+ * other cases. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+static __inline__ int atomic_sub_and_test(int i, atomic_t *v)
+{
+ unsigned char c;
+
+ __asm__ __volatile__(
+ LOCK "subl %2,%0; sete %1"
+ :"=m" (v->counter), "=qm" (c)
+ :"ir" (i), "m" (v->counter) : "memory");
+ return c;
+}
+
+/**
+ * atomic_inc - increment atomic variable
+ * @v: pointer of type atomic_t
+ *
+ * Atomically increments @v by 1. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+static __inline__ void atomic_inc(atomic_t *v)
+{
+ __asm__ __volatile__(
+ LOCK "incl %0"
+ :"=m" (v->counter)
+ :"m" (v->counter));
+}
+
+/**
+ * atomic_dec - decrement atomic variable
+ * @v: pointer of type atomic_t
+ *
+ * Atomically decrements @v by 1. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+static __inline__ void atomic_dec(atomic_t *v)
+{
+ __asm__ __volatile__(
+ LOCK "decl %0"
+ :"=m" (v->counter)
+ :"m" (v->counter));
+}
+
+/**
+ * atomic_dec_and_test - decrement and test
+ * @v: pointer of type atomic_t
+ *
+ * Atomically decrements @v by 1 and
+ * returns true if the result is 0, or false for all other
+ * cases. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+static __inline__ int atomic_dec_and_test(atomic_t *v)
+{
+ unsigned char c;
+
+ __asm__ __volatile__(
+ LOCK "decl %0; sete %1"
+ :"=m" (v->counter), "=qm" (c)
+ :"m" (v->counter) : "memory");
+ return c != 0;
+}
+
+/**
+ * atomic_inc_and_test - increment and test
+ * @v: pointer of type atomic_t
+ *
+ * Atomically increments @v by 1
+ * and returns true if the result is zero, or false for all
+ * other cases. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+static __inline__ int atomic_inc_and_test(atomic_t *v)
+{
+ unsigned char c;
+
+ __asm__ __volatile__(
+ LOCK "incl %0; sete %1"
+ :"=m" (v->counter), "=qm" (c)
+ :"m" (v->counter) : "memory");
+ return c != 0;
+}
+
+/**
+ * atomic_add_negative - add and test if negative
+ * @v: pointer of type atomic_t
+ * @i: integer value to add
+ *
+ * Atomically adds @i to @v and returns true
+ * if the result is negative, or false when
+ * result is greater than or equal to zero. Note that the guaranteed
+ * useful range of an atomic_t is only 24 bits.
+ */
+static __inline__ int atomic_add_negative(int i, atomic_t *v)
+{
+ unsigned char c;
+
+ __asm__ __volatile__(
+ LOCK "addl %2,%0; sets %1"
+ :"=m" (v->counter), "=qm" (c)
+ :"ir" (i), "m" (v->counter) : "memory");
+ return c;
+}
+
+/* These are x86-specific, used by some header files */
+#define atomic_clear_mask(mask, addr) \
+__asm__ __volatile__(LOCK "andl %0,%1" \
+: : "r" (~(mask)),"m" (*addr) : "memory")
+
+#define atomic_set_mask(mask, addr) \
+__asm__ __volatile__(LOCK "orl %0,%1" \
+: : "r" (mask),"m" (*addr) : "memory")
+
+/* Atomic operations are already serializing on x86 */
+#define smp_mb__before_atomic_dec() barrier()
+#define smp_mb__after_atomic_dec() barrier()
+#define smp_mb__before_atomic_inc() barrier()
+#define smp_mb__after_atomic_inc() barrier()
+
+#endif