Make bitmask 'and' operators return a result code

When 'and'ing two bitmasks (where 'andnot' is a variation on it), some
cases want to know whether the result is the empty set or not.  In
particular, the TLB IPI sending code wants to do cpumask operations and
determine if there are any CPU's left in the final set.

So this just makes the bitmask (and cpumask) functions return a boolean
for whether the result has any bits set.

Cc: stable@kernel.org (2.6.30, needed by TLB shootdown fix)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 10 insertions, 10 deletions

diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index c5ac87c..796df12 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -43,10 +43,10 @@
  * int cpu_isset(cpu, mask)		true iff bit 'cpu' set in mask
  * int cpu_test_and_set(cpu, mask)	test and set bit 'cpu' in mask
  *
- * void cpus_and(dst, src1, src2)	dst = src1 & src2  [intersection]
+ * int cpus_and(dst, src1, src2)	dst = src1 & src2  [intersection]
  * void cpus_or(dst, src1, src2)	dst = src1 | src2  [union]
  * void cpus_xor(dst, src1, src2)	dst = src1 ^ src2
- * void cpus_andnot(dst, src1, src2)	dst = src1 & ~src2
+ * int cpus_andnot(dst, src1, src2)	dst = src1 & ~src2
  * void cpus_complement(dst, src)	dst = ~src
  *
  * int cpus_equal(mask1, mask2)		Does mask1 == mask2?
@@ -179,10 +179,10 @@ static inline int __cpu_test_and_set(int cpu, cpumask_t *addr)
 }
 
 #define cpus_and(dst, src1, src2) __cpus_and(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_and(cpumask_t *dstp, const cpumask_t *src1p,
+static inline int __cpus_and(cpumask_t *dstp, const cpumask_t *src1p,
 					const cpumask_t *src2p, int nbits)
 {
-	bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits);
+	return bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits);
 }
 
 #define cpus_or(dst, src1, src2) __cpus_or(&(dst), &(src1), &(src2), NR_CPUS)
@@ -201,10 +201,10 @@ static inline void __cpus_xor(cpumask_t *dstp, const cpumask_t *src1p,
 
 #define cpus_andnot(dst, src1, src2) \
 				__cpus_andnot(&(dst), &(src1), &(src2), NR_CPUS)
-static inline void __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p,
+static inline int __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p,
 					const cpumask_t *src2p, int nbits)
 {
-	bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
+	return bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
 }
 
 #define cpus_complement(dst, src) __cpus_complement(&(dst), &(src), NR_CPUS)
@@ -738,11 +738,11 @@ static inline void cpumask_clear(struct cpumask *dstp)
  * @src1p: the first input
  * @src2p: the second input
  */
-static inline void cpumask_and(struct cpumask *dstp,
+static inline int cpumask_and(struct cpumask *dstp,
 			       const struct cpumask *src1p,
 			       const struct cpumask *src2p)
 {
-	bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
+	return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
 				       cpumask_bits(src2p), nr_cpumask_bits);
 }
 
@@ -779,11 +779,11 @@ static inline void cpumask_xor(struct cpumask *dstp,
  * @src1p: the first input
  * @src2p: the second input
  */
-static inline void cpumask_andnot(struct cpumask *dstp,
+static inline int cpumask_andnot(struct cpumask *dstp,
 				  const struct cpumask *src1p,
 				  const struct cpumask *src2p)
 {
-	bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
+	return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
 					  cpumask_bits(src2p), nr_cpumask_bits);
 }