1 files changed, 28 insertions, 5 deletions

diff --git a/arch/mips/include/asm/bitops.h b/arch/mips/include/asm/bitops.h
index b4bf754f7db3..42f88452c920 100644
--- a/arch/mips/include/asm/bitops.h
+++ b/arch/mips/include/asm/bitops.h
@@ -73,7 +73,8 @@ int __mips_test_and_clear_bit(unsigned long nr,
 			      volatile unsigned long *addr);
 int __mips_test_and_change_bit(unsigned long nr,
 			       volatile unsigned long *addr);
-
+bool __mips_xor_is_negative_byte(unsigned long mask,
+		volatile unsigned long *addr);
 
 /*
  * set_bit - Atomically set a bit in memory
@@ -279,6 +280,28 @@ static inline int test_and_change_bit(unsigned long nr,
 	return res;
 }
 
+static inline bool xor_unlock_is_negative_byte(unsigned long mask,
+		volatile unsigned long *p)
+{
+	unsigned long orig;
+	bool res;
+
+	smp_mb__before_atomic();
+
+	if (!kernel_uses_llsc) {
+		res = __mips_xor_is_negative_byte(mask, p);
+	} else {
+		orig = __test_bit_op(*p, "%0",
+				     "xor\t%1, %0, %3",
+				     "ir"(mask));
+		res = (orig & BIT(7)) != 0;
+	}
+
+	smp_llsc_mb();
+
+	return res;
+}
+
 #undef __bit_op
 #undef __test_bit_op
 
@@ -304,7 +327,7 @@ static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *
  * Return the bit position (0..63) of the most significant 1 bit in a word
  * Returns -1 if no 1 bit exists
  */
-static __always_inline unsigned long __fls(unsigned long word)
+static __always_inline __attribute_const__ unsigned long __fls(unsigned long word)
 {
 	int num;
 
@@ -370,7 +393,7 @@ static __always_inline unsigned long __fls(unsigned long word)
  * Returns 0..SZLONG-1
  * Undefined if no bit exists, so code should check against 0 first.
  */
-static __always_inline unsigned long __ffs(unsigned long word)
+static __always_inline __attribute_const__ unsigned long __ffs(unsigned long word)
 {
 	return __fls(word & -word);
 }
@@ -382,7 +405,7 @@ static __always_inline unsigned long __ffs(unsigned long word)
  * This is defined the same way as ffs.
  * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
  */
-static inline int fls(unsigned int x)
+static inline __attribute_const__ int fls(unsigned int x)
 {
 	int r;
 
@@ -435,7 +458,7 @@ static inline int fls(unsigned int x)
  * the libc and compiler builtin ffs routines, therefore
  * differs in spirit from the below ffz (man ffs).
  */
-static inline int ffs(int word)
+static inline __attribute_const__ int ffs(int word)
 {
 	if (!word)
 		return 0;