Import of Linux/MIPS 2.1.14.2

1 files changed, 53 insertions, 0 deletions

diff --git a/include/asm-generic/bitops.h b/include/asm-generic/bitops.h
new file mode 100644
index 000000000..130619840
--- /dev/null
+++ b/include/asm-generic/bitops.h
@@ -0,0 +1,53 @@
+#ifndef _ASM_GENERIC_BITOPS_H_
+#define _ASM_GENERIC_BITOPS_H_
+
+/*
+ * For the benefit of those who are trying to port Linux to another
+ * architecture, here are some C-language equivalents.  You should
+ * recode these in the native assembly language, if at all possible.
+ * To guarantee atomicity, these routines call cli() and sti() to
+ * disable interrupts while they operate.  (You have to provide inline
+ * routines to cli() and sti().)
+ *
+ * Also note, these routines assume that you have 32 bit integers.
+ * You will have to change this if you are trying to port Linux to the
+ * Alpha architecture or to a Cray.  :-)
+ * 
+ * C language equivalents written by Theodore Ts'o, 9/26/92
+ */
+
+extern __inline__ int set_bit(int nr,int * addr)
+{
+	int	mask, retval;
+
+	addr += nr >> 5;
+	mask = 1 << (nr & 0x1f);
+	cli();
+	retval = (mask & *addr) != 0;
+	*addr |= mask;
+	sti();
+	return retval;
+}
+
+extern __inline__ int clear_bit(int nr, int * addr)
+{
+	int	mask, retval;
+
+	addr += nr >> 5;
+	mask = 1 << (nr & 0x1f);
+	cli();
+	retval = (mask & *addr) != 0;
+	*addr &= ~mask;
+	sti();
+	return retval;
+}
+
+extern __inline__ int test_bit(int nr, int * addr)
+{
+	int	mask;
+
+	addr += nr >> 5;
+	mask = 1 << (nr & 0x1f);
+	return ((mask & *addr) != 0);
+}
+#endif /* _ASM_GENERIC_BITOPS_H */