From 6b9f9eadffb5f64801746593784e12f07f2fadd0 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 13 Jul 2015 13:17:07 +0900 Subject: [PATCH] linux_compat: handle __GFP_ZERO in kmalloc() Currently, kzalloc() returns zero-filled memory, while kmalloc() simply ignores the second argument and never fills the memory area with zeros. I want kmalloc(size, __GFP_ZERO) to behave as kzalloc() does, which will make it easier to add more memory allocator variants. With the introduction of __GFP_ZERO flag, going forward, kzmalloc() variants can fall back to kmalloc() enabling the __GFP_ZERO flag. Signed-off-by: Masahiro Yamada Reviewed-by: Heiko Schocher Acked-by: Simon Glass Reviewed-by: Lukasz Majewski --- include/linux/compat.h | 20 ++++++++++++-------- lib/linux_compat.c | 13 ++++++------- 2 files changed, 18 insertions(+), 15 deletions(-) diff --git a/include/linux/compat.h b/include/linux/compat.h index a3d136b70b..fbebf910ad 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -36,8 +36,19 @@ extern struct p_current *current; #define KERN_INFO #define KERN_DEBUG +#define GFP_ATOMIC ((gfp_t) 0) +#define GFP_KERNEL ((gfp_t) 0) +#define GFP_NOFS ((gfp_t) 0) +#define GFP_USER ((gfp_t) 0) +#define __GFP_NOWARN ((gfp_t) 0) +#define __GFP_ZERO ((__force gfp_t)0x8000u) /* Return zeroed page on success */ + void *kmalloc(size_t size, int flags); -void *kzalloc(size_t size, int flags); + +static inline void *kzalloc(size_t size, gfp_t flags) +{ + return kmalloc(size, flags | __GFP_ZERO); +} #define vmalloc(size) kmalloc(size, 0) #define __vmalloc(size, flags, pgsz) kmalloc(size, flags) static inline void *vzalloc(unsigned long size) @@ -77,13 +88,6 @@ void *kmem_cache_alloc(struct kmem_cache *obj, int flag); /* drivers/char/random.c */ #define get_random_bytes(...) -/* idr.c */ -#define GFP_ATOMIC ((gfp_t) 0) -#define GFP_KERNEL ((gfp_t) 0) -#define GFP_NOFS ((gfp_t) 0) -#define GFP_USER ((gfp_t) 0) -#define __GFP_NOWARN ((gfp_t) 0) - /* include/linux/leds.h */ struct led_trigger {}; diff --git a/lib/linux_compat.c b/lib/linux_compat.c index 8c7a7b5752..a936a7eac2 100644 --- a/lib/linux_compat.c +++ b/lib/linux_compat.c @@ -16,14 +16,13 @@ unsigned long copy_from_user(void *dest, const void *src, void *kmalloc(size_t size, int flags) { - return memalign(ARCH_DMA_MINALIGN, size); -} + void *p; -void *kzalloc(size_t size, int flags) -{ - void *ptr = kmalloc(size, flags); - memset(ptr, 0, size); - return ptr; + p = memalign(ARCH_DMA_MINALIGN, size); + if (flags & __GFP_ZERO) + memset(p, 0, size); + + return p; } struct kmem_cache *get_mem(int element_sz) -- 2.39.5