alloc_percpu: use __percpu annotation for sparse. Add __percpu for sparse. We have to make __kernel "__attribute__((address_space(0)))" so we can cast to it. Signed-off-by: Rusty Russell Cc: Al Viro --- include/asm-generic/percpu.h | 19 ++++++++++++------- include/linux/compiler.h | 4 +++- include/linux/percpu.h | 8 ++++---- 3 files changed, 19 insertions(+), 12 deletions(-) diff --git a/include/linux/compiler.h b/include/linux/compiler.h --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -5,7 +5,7 @@ #ifdef __CHECKER__ # define __user __attribute__((noderef, address_space(1))) -# define __kernel /* default address space */ +# define __kernel __attribute__((address_space(0))) # define __safe __attribute__((safe)) # define __force __attribute__((force)) # define __nocast __attribute__((nocast)) @@ -15,6 +15,7 @@ # define __acquire(x) __context__(x,1) # define __release(x) __context__(x,-1) # define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0) +# define __percpu __attribute__((noderef, address_space(3))) extern void __chk_user_ptr(const volatile void __user *); extern void __chk_io_ptr(const volatile void __iomem *); #else @@ -32,6 +33,7 @@ extern void __chk_io_ptr(const volatile # define __acquire(x) (void)0 # define __release(x) (void)0 # define __cond_lock(x,c) (c) +# define __percpu #endif #ifdef __KERNEL__ diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h --- a/include/asm-generic/percpu.h +++ b/include/asm-generic/percpu.h @@ -45,7 +45,9 @@ extern unsigned long __per_cpu_offset[NR * Only S390 provides its own means of moving the pointer. */ #ifndef SHIFT_PERCPU_PTR -#define SHIFT_PERCPU_PTR(__p, __offset) RELOC_HIDE((__p), (__offset)) +/* Weird cast keeps both GCC and sparse happy. */ +#define SHIFT_PERCPU_PTR(__p, __offset) \ + ((typeof(*__p) __kernel __force *)RELOC_HIDE((__p), (__offset))) #endif /* @@ -72,16 +74,19 @@ extern unsigned long __per_cpu_offset[NR #endif /* read_percpu_var */ /* Use RELOC_HIDE: some arch's SHIFT_PERCPU_PTR really want an identifier. */ +#define RELOC_PERCPU(addr, off) \ + ((typeof(*addr) __kernel __force *)RELOC_HIDE((addr), (off))) + /** * per_cpu_ptr - get a pointer to a particular cpu's allocated memory - * @ptr: the pointer returned from alloc_percpu + * @ptr: the pointer returned from alloc_percpu, or &per-cpu var * @cpu: the cpu whose memory you want to access * * Similar to per_cpu(), except for dynamic memory. * cpu_possible(@cpu) must be true. */ #define per_cpu_ptr(ptr, cpu) \ - RELOC_HIDE((ptr), (per_cpu_offset(cpu))) + RELOC_PERCPU((ptr), (per_cpu_offset(cpu))) /** * __get_cpu_ptr - get a pointer to this cpu's allocated memory @@ -89,8 +94,8 @@ extern unsigned long __per_cpu_offset[NR * * Similar to __get_cpu_var(), except for dynamic memory. */ -#define __get_cpu_ptr(ptr) RELOC_HIDE(ptr, my_cpu_offset) -#define __raw_get_cpu_ptr(ptr) RELOC_HIDE(ptr, __my_cpu_offset) +#define __get_cpu_ptr(ptr) RELOC_PERCPU(ptr, my_cpu_offset) +#define __raw_get_cpu_ptr(ptr) RELOC_PERCPU(ptr, __my_cpu_offset) #ifndef read_percpu_ptr /** @@ -124,7 +129,7 @@ extern void setup_per_cpu_areas(void); #define PER_CPU_ATTRIBUTES #endif -#define DECLARE_PER_CPU(type, name) extern PER_CPU_ATTRIBUTES \ - __typeof__(type) per_cpu_var(name) +#define DECLARE_PER_CPU(type, name) \ + extern PER_CPU_ATTRIBUTES __percpu __typeof__(type) per_cpu_var(name) #endif /* _ASM_GENERIC_PERCPU_H_ */ diff --git a/include/linux/percpu.h b/include/linux/percpu.h --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -11,7 +11,7 @@ #ifdef CONFIG_SMP #define DEFINE_PER_CPU(type, name) \ __attribute__((__section__(".data.percpu"))) \ - PER_CPU_ATTRIBUTES __typeof__(type) name + PER_CPU_ATTRIBUTES __typeof__(type) __percpu name #ifdef MODULE #define SHARED_ALIGNED_SECTION ".data.percpu" @@ -21,15 +21,15 @@ #define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \ __attribute__((__section__(SHARED_ALIGNED_SECTION))) \ - PER_CPU_ATTRIBUTES __typeof__(type) name \ + PER_CPU_ATTRIBUTES __typeof__(type) __percpu name \ ____cacheline_aligned_in_smp #define DEFINE_PER_CPU_PAGE_ALIGNED(type, name) \ __attribute__((__section__(".data.percpu.page_aligned"))) \ - PER_CPU_ATTRIBUTES __typeof__(type) name + PER_CPU_ATTRIBUTES __typeof__(type) __percpu name #else #define DEFINE_PER_CPU(type, name) \ - PER_CPU_ATTRIBUTES __typeof__(type) name + PER_CPU_ATTRIBUTES __typeof__(type) __percpu name #define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \ DEFINE_PER_CPU(type, name)