In KASAN development I noticed that the powerpc-specific bitops
were not being picked up by the KASAN test suite.
Instrumentation is done via the bitops/instrumented-{atomic,lock}.h
headers. They require that arch-specific versions of bitop functions
are renamed to arch_*. Do this renaming.
For clear_bit_unlock_is_negative_byte, the current implementation
uses the PG_waiters constant. This works because it's a preprocessor
macro - so it's only actually evaluated in contexts where PG_waiters
is defined. With instrumentation however, it becomes a static inline
function, and all of a sudden we need the actual value of PG_waiters.
Because of the order of header includes, it's not available and we
fail to compile. Instead, manually specify that we care about bit 7.
This is still correct: bit 7 is the bit that would mark a negative
byte.
Cc: Nicholas Piggin <npiggin@xxxxxxxxx> # clear_bit_unlock_negative_byte
Signed-off-by: Daniel Axtens <dja@xxxxxxxxxx>
---
arch/powerpc/include/asm/bitops.h | 31 +++++++++++++++++++------------
1 file changed, 19 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/include/asm/bitops.h b/arch/powerpc/include/asm/bitops.h
index 603aed229af7..8615b2bc35fe 100644
--- a/arch/powerpc/include/asm/bitops.h
+++ b/arch/powerpc/include/asm/bitops.h
@@ -86,22 +86,22 @@ DEFINE_BITOP(clear_bits, andc, "")
DEFINE_BITOP(clear_bits_unlock, andc, PPC_RELEASE_BARRIER)
DEFINE_BITOP(change_bits, xor, "")
-static __inline__ void set_bit(int nr, volatile unsigned long *addr)
+static __inline__ void arch_set_bit(int nr, volatile unsigned long *addr)
{
set_bits(BIT_MASK(nr), addr + BIT_WORD(nr));
}
-static __inline__ void clear_bit(int nr, volatile unsigned long *addr)
+static __inline__ void arch_clear_bit(int nr, volatile unsigned long *addr)
{
clear_bits(BIT_MASK(nr), addr + BIT_WORD(nr));
}
-static __inline__ void clear_bit_unlock(int nr, volatile unsigned long *addr)
+static __inline__ void arch_clear_bit_unlock(int nr, volatile unsigned long *addr)
{
clear_bits_unlock(BIT_MASK(nr), addr + BIT_WORD(nr));
}
-static __inline__ void change_bit(int nr, volatile unsigned long *addr)
+static __inline__ void arch_change_bit(int nr, volatile unsigned long *addr)
{
change_bits(BIT_MASK(nr), addr + BIT_WORD(nr));
}
@@ -138,26 +138,26 @@ DEFINE_TESTOP(test_and_clear_bits, andc, PPC_ATOMIC_ENTRY_BARRIER,
DEFINE_TESTOP(test_and_change_bits, xor, PPC_ATOMIC_ENTRY_BARRIER,
PPC_ATOMIC_EXIT_BARRIER, 0)
-static __inline__ int test_and_set_bit(unsigned long nr,
+static __inline__ int arch_test_and_set_bit(unsigned long nr,
volatile unsigned long *addr)
{
return test_and_set_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0;
}
-static __inline__ int test_and_set_bit_lock(unsigned long nr,
+static __inline__ int arch_test_and_set_bit_lock(unsigned long nr,
volatile unsigned long *addr)
{
return test_and_set_bits_lock(BIT_MASK(nr),
addr + BIT_WORD(nr)) != 0;
}
-static __inline__ int test_and_clear_bit(unsigned long nr,
+static __inline__ int arch_test_and_clear_bit(unsigned long nr,
volatile unsigned long *addr)
{
return test_and_clear_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0;
}
-static __inline__ int test_and_change_bit(unsigned long nr,
+static __inline__ int arch_test_and_change_bit(unsigned long nr,
volatile unsigned long *addr)
{
return test_and_change_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0;
@@ -185,15 +185,18 @@ static __inline__ unsigned long clear_bit_unlock_return_word(int nr,
return old;
}
-/* This is a special function for mm/filemap.c */
-#define clear_bit_unlock_is_negative_byte(nr, addr) \
- (clear_bit_unlock_return_word(nr, addr) & BIT_MASK(PG_waiters))
+/*
+ * This is a special function for mm/filemap.c
+ * Bit 7 corresponds to PG_waiters.
+ */
+#define arch_clear_bit_unlock_is_negative_byte(nr, addr) \
+ (clear_bit_unlock_return_word(nr, addr) & BIT_MASK(7))
#endif /* CONFIG_PPC64 */
#include <asm-generic/bitops/non-atomic.h>
-static __inline__ void __clear_bit_unlock(int nr, volatile unsigned long *addr)
+static __inline__ void arch___clear_bit_unlock(int nr, volatile unsigned long *addr)
{
__asm__ __volatile__(PPC_RELEASE_BARRIER "" ::: "memory");
__clear_bit(nr, addr);
@@ -239,6 +242,10 @@ unsigned long __arch_hweight64(__u64 w);
#include <asm-generic/bitops/find.h>
+/* wrappers that deal with KASAN instrumentation */
+#include <asm-generic/bitops/instrumented-atomic.h>
+#include <asm-generic/bitops/instrumented-lock.h>
+
/* Little-endian versions */
#include <asm-generic/bitops/le.h>
--
2.20.1
