diff options
Diffstat (limited to 'include/linux/slab.h')
| -rw-r--r-- | include/linux/slab.h | 196 |
1 files changed, 96 insertions, 100 deletions
diff --git a/include/linux/slab.h b/include/linux/slab.h index 0fefdf528e0d..90877fcde70b 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -29,6 +29,8 @@ #define SLAB_RED_ZONE ((slab_flags_t __force)0x00000400U) /* DEBUG: Poison objects */ #define SLAB_POISON ((slab_flags_t __force)0x00000800U) +/* Indicate a kmalloc slab */ +#define SLAB_KMALLOC ((slab_flags_t __force)0x00001000U) /* Align objs on cache lines */ #define SLAB_HWCACHE_ALIGN ((slab_flags_t __force)0x00002000U) /* Use GFP_DMA memory */ @@ -106,7 +108,7 @@ # define SLAB_ACCOUNT 0 #endif -#ifdef CONFIG_KASAN +#ifdef CONFIG_KASAN_GENERIC #define SLAB_KASAN ((slab_flags_t __force)0x08000000U) #else #define SLAB_KASAN 0 @@ -119,6 +121,12 @@ */ #define SLAB_NO_USER_FLAGS ((slab_flags_t __force)0x10000000U) +#ifdef CONFIG_KFENCE +#define SLAB_SKIP_KFENCE ((slab_flags_t __force)0x20000000U) +#else +#define SLAB_SKIP_KFENCE 0 +#endif + /* The following flags affect the page allocator grouping pages by mobility */ /* Objects are reclaimable */ #define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U) @@ -184,11 +192,25 @@ int kmem_cache_shrink(struct kmem_cache *s); /* * Common kmalloc functions provided by all allocators */ -void * __must_check krealloc(const void *objp, size_t new_size, gfp_t flags) __alloc_size(2); +void * __must_check krealloc(const void *objp, size_t new_size, gfp_t flags) __realloc_size(2); void kfree(const void *objp); void kfree_sensitive(const void *objp); size_t __ksize(const void *objp); + +/** + * ksize - Report actual allocation size of associated object + * + * @objp: Pointer returned from a prior kmalloc()-family allocation. + * + * This should not be used for writing beyond the originally requested + * allocation size. Either use krealloc() or round up the allocation size + * with kmalloc_size_roundup() prior to allocation. If this is used to + * access beyond the originally requested allocation size, UBSAN_BOUNDS + * and/or FORTIFY_SOURCE may trip, since they only know about the + * originally allocated size via the __alloc_size attribute. + */ size_t ksize(const void *objp); + #ifdef CONFIG_PRINTK bool kmem_valid_obj(void *object); void kmem_dump_obj(void *object); @@ -243,27 +265,17 @@ static inline unsigned int arch_slab_minalign(void) #ifdef CONFIG_SLAB /* - * The largest kmalloc size supported by the SLAB allocators is - * 32 megabyte (2^25) or the maximum allocatable page order if that is - * less than 32 MB. - * - * WARNING: Its not easy to increase this value since the allocators have - * to do various tricks to work around compiler limitations in order to - * ensure proper constant folding. + * SLAB and SLUB directly allocates requests fitting in to an order-1 page + * (PAGE_SIZE*2). Larger requests are passed to the page allocator. */ -#define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \ - (MAX_ORDER + PAGE_SHIFT - 1) : 25) -#define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH +#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 5 #endif #endif #ifdef CONFIG_SLUB -/* - * SLUB directly allocates requests fitting in to an order-1 page - * (PAGE_SIZE*2). Larger requests are passed to the page allocator. - */ #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) #ifndef KMALLOC_SHIFT_LOW @@ -415,10 +427,6 @@ static __always_inline unsigned int __kmalloc_index(size_t size, if (size <= 512 * 1024) return 19; if (size <= 1024 * 1024) return 20; if (size <= 2 * 1024 * 1024) return 21; - if (size <= 4 * 1024 * 1024) return 22; - if (size <= 8 * 1024 * 1024) return 23; - if (size <= 16 * 1024 * 1024) return 24; - if (size <= 32 * 1024 * 1024) return 25; if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant) BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()"); @@ -428,6 +436,7 @@ static __always_inline unsigned int __kmalloc_index(size_t size, /* Will never be reached. Needed because the compiler may complain */ return -1; } +static_assert(PAGE_SHIFT <= 20); #define kmalloc_index(s) __kmalloc_index(s, true) #endif /* !CONFIG_SLOB */ @@ -456,42 +465,22 @@ static __always_inline void kfree_bulk(size_t size, void **p) kmem_cache_free_bulk(NULL, size, p); } -#ifdef CONFIG_NUMA void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignment __alloc_size(1); void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node) __assume_slab_alignment __malloc; -#else -static __always_inline __alloc_size(1) void *__kmalloc_node(size_t size, gfp_t flags, int node) -{ - return __kmalloc(size, flags); -} - -static __always_inline void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node) -{ - return kmem_cache_alloc(s, flags); -} -#endif #ifdef CONFIG_TRACING -extern void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t flags, size_t size) - __assume_slab_alignment __alloc_size(3); - -#ifdef CONFIG_NUMA -extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, - int node, size_t size) __assume_slab_alignment - __alloc_size(4); -#else -static __always_inline __alloc_size(4) void *kmem_cache_alloc_node_trace(struct kmem_cache *s, - gfp_t gfpflags, int node, size_t size) -{ - return kmem_cache_alloc_trace(s, gfpflags, size); -} -#endif /* CONFIG_NUMA */ +void *kmalloc_trace(struct kmem_cache *s, gfp_t flags, size_t size) + __assume_kmalloc_alignment __alloc_size(3); +void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, + int node, size_t size) __assume_kmalloc_alignment + __alloc_size(4); #else /* CONFIG_TRACING */ -static __always_inline __alloc_size(3) void *kmem_cache_alloc_trace(struct kmem_cache *s, - gfp_t flags, size_t size) +/* Save a function call when CONFIG_TRACING=n */ +static __always_inline __alloc_size(3) +void *kmalloc_trace(struct kmem_cache *s, gfp_t flags, size_t size) { void *ret = kmem_cache_alloc(s, flags); @@ -499,8 +488,9 @@ static __always_inline __alloc_size(3) void *kmem_cache_alloc_trace(struct kmem_ return ret; } -static __always_inline void *kmem_cache_alloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, - int node, size_t size) +static __always_inline __alloc_size(4) +void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, + int node, size_t size) { void *ret = kmem_cache_alloc_node(s, gfpflags, node); @@ -509,25 +499,11 @@ static __always_inline void *kmem_cache_alloc_node_trace(struct kmem_cache *s, g } #endif /* CONFIG_TRACING */ -extern void *kmalloc_order(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment - __alloc_size(1); +void *kmalloc_large(size_t size, gfp_t flags) __assume_page_alignment + __alloc_size(1); -#ifdef CONFIG_TRACING -extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order) - __assume_page_alignment __alloc_size(1); -#else -static __always_inline __alloc_size(1) void *kmalloc_order_trace(size_t size, gfp_t flags, - unsigned int order) -{ - return kmalloc_order(size, flags, order); -} -#endif - -static __always_inline __alloc_size(1) void *kmalloc_large(size_t size, gfp_t flags) -{ - unsigned int order = get_order(size); - return kmalloc_order_trace(size, flags, order); -} +void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_alignment + __alloc_size(1); /** * kmalloc - allocate memory @@ -597,7 +573,7 @@ static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) if (!index) return ZERO_SIZE_PTR; - return kmem_cache_alloc_trace( + return kmalloc_trace( kmalloc_caches[kmalloc_type(flags)][index], flags, size); #endif @@ -605,23 +581,35 @@ static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) return __kmalloc(size, flags); } +#ifndef CONFIG_SLOB static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) { -#ifndef CONFIG_SLOB - if (__builtin_constant_p(size) && - size <= KMALLOC_MAX_CACHE_SIZE) { - unsigned int i = kmalloc_index(size); + if (__builtin_constant_p(size)) { + unsigned int index; - if (!i) + if (size > KMALLOC_MAX_CACHE_SIZE) + return kmalloc_large_node(size, flags, node); + + index = kmalloc_index(size); + + if (!index) return ZERO_SIZE_PTR; - return kmem_cache_alloc_node_trace( - kmalloc_caches[kmalloc_type(flags)][i], - flags, node, size); + return kmalloc_node_trace( + kmalloc_caches[kmalloc_type(flags)][index], + flags, node, size); } -#endif return __kmalloc_node(size, flags, node); } +#else +static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) +{ + if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) + return kmalloc_large_node(size, flags, node); + + return __kmalloc_node(size, flags, node); +} +#endif /** * kmalloc_array - allocate memory for an array. @@ -647,10 +635,10 @@ static inline __alloc_size(1, 2) void *kmalloc_array(size_t n, size_t size, gfp_ * @new_size: new size of a single member of the array * @flags: the type of memory to allocate (see kmalloc) */ -static inline __alloc_size(2, 3) void * __must_check krealloc_array(void *p, - size_t new_n, - size_t new_size, - gfp_t flags) +static inline __realloc_size(2, 3) void * __must_check krealloc_array(void *p, + size_t new_n, + size_t new_size, + gfp_t flags) { size_t bytes; @@ -671,6 +659,12 @@ static inline __alloc_size(1, 2) void *kcalloc(size_t n, size_t size, gfp_t flag return kmalloc_array(n, size, flags | __GFP_ZERO); } +void *__kmalloc_node_track_caller(size_t size, gfp_t flags, int node, + unsigned long caller) __alloc_size(1); +#define kmalloc_node_track_caller(size, flags, node) \ + __kmalloc_node_track_caller(size, flags, node, \ + _RET_IP_) + /* * kmalloc_track_caller is a special version of kmalloc that records the * calling function of the routine calling it for slab leak tracking instead @@ -679,9 +673,9 @@ static inline __alloc_size(1, 2) void *kcalloc(size_t n, size_t size, gfp_t flag * allocator where we care about the real place the memory allocation * request comes from. */ -extern void *__kmalloc_track_caller(size_t size, gfp_t flags, unsigned long caller); #define kmalloc_track_caller(size, flags) \ - __kmalloc_track_caller(size, flags, _RET_IP_) + __kmalloc_node_track_caller(size, flags, \ + NUMA_NO_NODE, _RET_IP_) static inline __alloc_size(1, 2) void *kmalloc_array_node(size_t n, size_t size, gfp_t flags, int node) @@ -700,21 +694,6 @@ static inline __alloc_size(1, 2) void *kcalloc_node(size_t n, size_t size, gfp_t return kmalloc_array_node(n, size, flags | __GFP_ZERO, node); } - -#ifdef CONFIG_NUMA -extern void *__kmalloc_node_track_caller(size_t size, gfp_t flags, int node, - unsigned long caller) __alloc_size(1); -#define kmalloc_node_track_caller(size, flags, node) \ - __kmalloc_node_track_caller(size, flags, node, \ - _RET_IP_) - -#else /* CONFIG_NUMA */ - -#define kmalloc_node_track_caller(size, flags, node) \ - kmalloc_track_caller(size, flags) - -#endif /* CONFIG_NUMA */ - /* * Shortcuts */ @@ -774,11 +753,28 @@ static inline __alloc_size(1, 2) void *kvcalloc(size_t n, size_t size, gfp_t fla } extern void *kvrealloc(const void *p, size_t oldsize, size_t newsize, gfp_t flags) - __alloc_size(3); + __realloc_size(3); extern void kvfree(const void *addr); extern void kvfree_sensitive(const void *addr, size_t len); unsigned int kmem_cache_size(struct kmem_cache *s); + +/** + * kmalloc_size_roundup - Report allocation bucket size for the given size + * + * @size: Number of bytes to round up from. + * + * This returns the number of bytes that would be available in a kmalloc() + * allocation of @size bytes. For example, a 126 byte request would be + * rounded up to the next sized kmalloc bucket, 128 bytes. (This is strictly + * for the general-purpose kmalloc()-based allocations, and is not for the + * pre-sized kmem_cache_alloc()-based allocations.) + * + * Use this to kmalloc() the full bucket size ahead of time instead of using + * ksize() to query the size after an allocation. + */ +size_t kmalloc_size_roundup(size_t size); + void __init kmem_cache_init_late(void); #if defined(CONFIG_SMP) && defined(CONFIG_SLAB) |