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-rw-r--r--arch/cris/include/asm/bitops.h166
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/cris/include/asm/bitops.h b/arch/cris/include/asm/bitops.h
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+++ b/arch/cris/include/asm/bitops.h
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+/* asm/bitops.h for Linux/CRIS
+ *
+ * TODO: asm versions if speed is needed
+ *
+ * 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).
+ */
+
+#ifndef _CRIS_BITOPS_H
+#define _CRIS_BITOPS_H
+
+/* Currently this is unsuitable for consumption outside the kernel. */
+#ifdef __KERNEL__
+
+#ifndef _LINUX_BITOPS_H
+#error only <linux/bitops.h> can be included directly
+#endif
+
+#include <arch/bitops.h>
+#include <asm/system.h>
+#include <asm/atomic.h>
+#include <linux/compiler.h>
+
+/*
+ * 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.
+ */
+
+#define set_bit(nr, addr) (void)test_and_set_bit(nr, addr)
+
+/*
+ * clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * 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.
+ */
+
+#define clear_bit(nr, addr) (void)test_and_clear_bit(nr, addr)
+
+/*
+ * change_bit - Toggle a bit in memory
+ * @nr: Bit to change
+ * @addr: Address to start counting from
+ *
+ * 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.
+ */
+
+#define change_bit(nr, addr) (void)test_and_change_bit(nr, addr)
+
+/**
+ * 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 test_and_set_bit(int nr, volatile unsigned long *addr)
+{
+ unsigned int mask, retval;
+ unsigned long flags;
+ unsigned int *adr = (unsigned int *)addr;
+
+ adr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ cris_atomic_save(addr, flags);
+ retval = (mask & *adr) != 0;
+ *adr |= mask;
+ cris_atomic_restore(addr, flags);
+ return retval;
+}
+
+/*
+ * clear_bit() doesn't provide any barrier for the compiler.
+ */
+#define smp_mb__before_clear_bit() barrier()
+#define smp_mb__after_clear_bit() barrier()
+
+/**
+ * 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 test_and_clear_bit(int nr, volatile unsigned long *addr)
+{
+ unsigned int mask, retval;
+ unsigned long flags;
+ unsigned int *adr = (unsigned int *)addr;
+
+ adr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ cris_atomic_save(addr, flags);
+ retval = (mask & *adr) != 0;
+ *adr &= ~mask;
+ cris_atomic_restore(addr, flags);
+ return retval;
+}
+
+/**
+ * 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 test_and_change_bit(int nr, volatile unsigned long *addr)
+{
+ unsigned int mask, retval;
+ unsigned long flags;
+ unsigned int *adr = (unsigned int *)addr;
+ adr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ cris_atomic_save(addr, flags);
+ retval = (mask & *adr) != 0;
+ *adr ^= mask;
+ cris_atomic_restore(addr, flags);
+ return retval;
+}
+
+#include <asm-generic/bitops/non-atomic.h>
+
+/*
+ * Since we define it "external", it collides with the built-in
+ * definition, which doesn't have the same semantics. We don't want to
+ * use -fno-builtin, so just hide the name ffs.
+ */
+#define ffs kernel_ffs
+
+#include <asm-generic/bitops/fls.h>
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/hweight.h>
+#include <asm-generic/bitops/find.h>
+#include <asm-generic/bitops/lock.h>
+
+#include <asm-generic/bitops/ext2-non-atomic.h>
+
+#define ext2_set_bit_atomic(l,n,a) test_and_set_bit(n,a)
+#define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a)
+
+#include <asm-generic/bitops/minix.h>
+#include <asm-generic/bitops/sched.h>
+
+#endif /* __KERNEL__ */
+
+#endif /* _CRIS_BITOPS_H */