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authorLinus Torvalds <torvalds@linux-foundation.org>2019-12-06 13:36:31 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-12-06 13:36:31 -0800
commit43a2898631a8beee66c1d64c1e860f43d96b2e91 (patch)
treefc2a43ca77627443d09621bdb1e364e41b4f3890 /include/asm-generic/bitops
parentf89d416a8676fe36de8be0f7c2e1ac6cd51410a8 (diff)
parent4f4afc2c9599520300b3f2b3666d2034fca03df3 (diff)
Merge tag 'powerpc-5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull more powerpc updates from Michael Ellerman: "A few commits splitting the KASAN instrumented bitops header in three, to match the split of the asm-generic bitops headers. This is needed on powerpc because we use the generic bitops for the non-atomic case only, whereas the existing KASAN instrumented bitops assume all the underlying operations are provided by the arch as arch_foo() versions. Thanks to: Daniel Axtens & Christophe Leroy" * tag 'powerpc-5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: docs/core-api: Remove possibly confusing sub-headings from Bit Operations powerpc: support KASAN instrumentation of bitops kasan: support instrumented bitops combined with generic bitops
Diffstat (limited to 'include/asm-generic/bitops')
-rw-r--r--include/asm-generic/bitops/instrumented-atomic.h100
-rw-r--r--include/asm-generic/bitops/instrumented-lock.h81
-rw-r--r--include/asm-generic/bitops/instrumented-non-atomic.h114
3 files changed, 295 insertions, 0 deletions
diff --git a/include/asm-generic/bitops/instrumented-atomic.h b/include/asm-generic/bitops/instrumented-atomic.h
new file mode 100644
index 000000000000..18ce3c9e8eec
--- /dev/null
+++ b/include/asm-generic/bitops/instrumented-atomic.h
@@ -0,0 +1,100 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * This file provides wrappers with sanitizer instrumentation for atomic bit
+ * operations.
+ *
+ * To use this functionality, an arch's bitops.h file needs to define each of
+ * the below bit operations with an arch_ prefix (e.g. arch_set_bit(),
+ * arch___set_bit(), etc.).
+ */
+#ifndef _ASM_GENERIC_BITOPS_INSTRUMENTED_ATOMIC_H
+#define _ASM_GENERIC_BITOPS_INSTRUMENTED_ATOMIC_H
+
+#include <linux/kasan-checks.h>
+
+/**
+ * set_bit - Atomically set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This is a relaxed atomic operation (no implied memory barriers).
+ *
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static inline void set_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ arch_set_bit(nr, addr);
+}
+
+/**
+ * clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * This is a relaxed atomic operation (no implied memory barriers).
+ */
+static inline void clear_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ arch_clear_bit(nr, addr);
+}
+
+/**
+ * change_bit - Toggle a bit in memory
+ * @nr: Bit to change
+ * @addr: Address to start counting from
+ *
+ * This is a relaxed atomic operation (no implied memory barriers).
+ *
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static inline void change_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ arch_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 is an atomic fully-ordered operation (implied full memory barrier).
+ */
+static inline bool test_and_set_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ return arch_test_and_set_bit(nr, addr);
+}
+
+/**
+ * test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ *
+ * This is an atomic fully-ordered operation (implied full memory barrier).
+ */
+static inline bool test_and_clear_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ return arch_test_and_clear_bit(nr, addr);
+}
+
+/**
+ * test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @addr: Address to count from
+ *
+ * This is an atomic fully-ordered operation (implied full memory barrier).
+ */
+static inline bool test_and_change_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ return arch_test_and_change_bit(nr, addr);
+}
+
+#endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H */
diff --git a/include/asm-generic/bitops/instrumented-lock.h b/include/asm-generic/bitops/instrumented-lock.h
new file mode 100644
index 000000000000..ec53fdeea9ec
--- /dev/null
+++ b/include/asm-generic/bitops/instrumented-lock.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * This file provides wrappers with sanitizer instrumentation for bit
+ * locking operations.
+ *
+ * To use this functionality, an arch's bitops.h file needs to define each of
+ * the below bit operations with an arch_ prefix (e.g. arch_set_bit(),
+ * arch___set_bit(), etc.).
+ */
+#ifndef _ASM_GENERIC_BITOPS_INSTRUMENTED_LOCK_H
+#define _ASM_GENERIC_BITOPS_INSTRUMENTED_LOCK_H
+
+#include <linux/kasan-checks.h>
+
+/**
+ * clear_bit_unlock - Clear a bit in memory, for unlock
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This operation is atomic and provides release barrier semantics.
+ */
+static inline void clear_bit_unlock(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ arch_clear_bit_unlock(nr, addr);
+}
+
+/**
+ * __clear_bit_unlock - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * This is a non-atomic operation but implies a release barrier before the
+ * memory operation. It can be used for an unlock if no other CPUs can
+ * concurrently modify other bits in the word.
+ */
+static inline void __clear_bit_unlock(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ arch___clear_bit_unlock(nr, addr);
+}
+
+/**
+ * test_and_set_bit_lock - Set a bit and return its old value, for lock
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and provides acquire barrier semantics if
+ * the returned value is 0.
+ * It can be used to implement bit locks.
+ */
+static inline bool test_and_set_bit_lock(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ return arch_test_and_set_bit_lock(nr, addr);
+}
+
+#if defined(arch_clear_bit_unlock_is_negative_byte)
+/**
+ * clear_bit_unlock_is_negative_byte - Clear a bit in memory and test if bottom
+ * byte is negative, for unlock.
+ * @nr: the bit to clear
+ * @addr: the address to start counting from
+ *
+ * This operation is atomic and provides release barrier semantics.
+ *
+ * This is a bit of a one-trick-pony for the filemap code, which clears
+ * PG_locked and tests PG_waiters,
+ */
+static inline bool
+clear_bit_unlock_is_negative_byte(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ return arch_clear_bit_unlock_is_negative_byte(nr, addr);
+}
+/* Let everybody know we have it. */
+#define clear_bit_unlock_is_negative_byte clear_bit_unlock_is_negative_byte
+#endif
+
+#endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_LOCK_H */
diff --git a/include/asm-generic/bitops/instrumented-non-atomic.h b/include/asm-generic/bitops/instrumented-non-atomic.h
new file mode 100644
index 000000000000..95ff28d128a1
--- /dev/null
+++ b/include/asm-generic/bitops/instrumented-non-atomic.h
@@ -0,0 +1,114 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * This file provides wrappers with sanitizer instrumentation for non-atomic
+ * bit operations.
+ *
+ * To use this functionality, an arch's bitops.h file needs to define each of
+ * the below bit operations with an arch_ prefix (e.g. arch_set_bit(),
+ * arch___set_bit(), etc.).
+ */
+#ifndef _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H
+#define _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H
+
+#include <linux/kasan-checks.h>
+
+/**
+ * __set_bit - Set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * Unlike set_bit(), this function is non-atomic. If it is called on the same
+ * region of memory concurrently, the effect may be that only one operation
+ * succeeds.
+ */
+static inline void __set_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ arch___set_bit(nr, addr);
+}
+
+/**
+ * __clear_bit - Clears a bit in memory
+ * @nr: the bit to clear
+ * @addr: the address to start counting from
+ *
+ * Unlike clear_bit(), this function is non-atomic. If it is called on the same
+ * region of memory concurrently, the effect may be that only one operation
+ * succeeds.
+ */
+static inline void __clear_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ arch___clear_bit(nr, addr);
+}
+
+/**
+ * __change_bit - Toggle a bit in memory
+ * @nr: the bit to change
+ * @addr: the address to start counting from
+ *
+ * Unlike change_bit(), this function is non-atomic. If it is called on the same
+ * region of memory concurrently, the effect may be that only one operation
+ * succeeds.
+ */
+static inline void __change_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ arch___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 non-atomic. If two instances of this operation race, one
+ * can appear to succeed but actually fail.
+ */
+static inline bool __test_and_set_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ return arch___test_and_set_bit(nr, addr);
+}
+
+/**
+ * __test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic. If two instances of this operation race, one
+ * can appear to succeed but actually fail.
+ */
+static inline bool __test_and_clear_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ return arch___test_and_clear_bit(nr, addr);
+}
+
+/**
+ * __test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic. If two instances of this operation race, one
+ * can appear to succeed but actually fail.
+ */
+static inline bool __test_and_change_bit(long nr, volatile unsigned long *addr)
+{
+ kasan_check_write(addr + BIT_WORD(nr), sizeof(long));
+ return arch___test_and_change_bit(nr, addr);
+}
+
+/**
+ * test_bit - Determine whether a bit is set
+ * @nr: bit number to test
+ * @addr: Address to start counting from
+ */
+static inline bool test_bit(long nr, const volatile unsigned long *addr)
+{
+ kasan_check_read(addr + BIT_WORD(nr), sizeof(long));
+ return arch_test_bit(nr, addr);
+}
+
+#endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H */