x86, um: ... and asm-x86 move

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 130 insertions, 0 deletions

diff --git a/arch/x86/include/asm/sync_bitops.h b/arch/x86/include/asm/sync_bitops.h
new file mode 100644
index 000000000000..b689bee71104
--- /dev/null
+++ b/arch/x86/include/asm/sync_bitops.h
@@ -0,0 +1,130 @@
+#ifndef ASM_X86__SYNC_BITOPS_H
+#define ASM_X86__SYNC_BITOPS_H
+
+/*
+ * Copyright 1992, Linus Torvalds.
+ */
+
+/*
+ * These have to be done with inline assembly: that way the bit-setting
+ * is guaranteed to be atomic. All bit operations return 0 if the bit
+ * was cleared before the operation and != 0 if it was not.
+ *
+ * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
+ */
+
+#define ADDR (*(volatile long *)addr)
+
+/**
+ * sync_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 sync_set_bit(int nr, volatile unsigned long *addr)
+{
+	asm volatile("lock; btsl %1,%0"
+		     : "+m" (ADDR)
+		     : "Ir" (nr)
+		     : "memory");
+}
+
+/**
+ * sync_clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * sync_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 sync_clear_bit(int nr, volatile unsigned long *addr)
+{
+	asm volatile("lock; btrl %1,%0"
+		     : "+m" (ADDR)
+		     : "Ir" (nr)
+		     : "memory");
+}
+
+/**
+ * sync_change_bit - Toggle a bit in memory
+ * @nr: Bit to change
+ * @addr: Address to start counting from
+ *
+ * sync_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 sync_change_bit(int nr, volatile unsigned long *addr)
+{
+	asm volatile("lock; btcl %1,%0"
+		     : "+m" (ADDR)
+		     : "Ir" (nr)
+		     : "memory");
+}
+
+/**
+ * sync_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 sync_test_and_set_bit(int nr, volatile unsigned long *addr)
+{
+	int oldbit;
+
+	asm volatile("lock; btsl %2,%1\n\tsbbl %0,%0"
+		     : "=r" (oldbit), "+m" (ADDR)
+		     : "Ir" (nr) : "memory");
+	return oldbit;
+}
+
+/**
+ * sync_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 sync_test_and_clear_bit(int nr, volatile unsigned long *addr)
+{
+	int oldbit;
+
+	asm volatile("lock; btrl %2,%1\n\tsbbl %0,%0"
+		     : "=r" (oldbit), "+m" (ADDR)
+		     : "Ir" (nr) : "memory");
+	return oldbit;
+}
+
+/**
+ * sync_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 sync_test_and_change_bit(int nr, volatile unsigned long *addr)
+{
+	int oldbit;
+
+	asm volatile("lock; btcl %2,%1\n\tsbbl %0,%0"
+		     : "=r" (oldbit), "+m" (ADDR)
+		     : "Ir" (nr) : "memory");
+	return oldbit;
+}
+
+#define sync_test_bit(nr, addr) test_bit(nr, addr)
+
+#undef ADDR
+
+#endif /* ASM_X86__SYNC_BITOPS_H */