diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/slab.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/include/linux/slab.h b/include/linux/slab.h index cbb64a2698f5..7701b38cedec 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -983,6 +983,33 @@ void *kmalloc_nolock_noprof(size_t size, gfp_t gfp_flags, int node); }) /** + * __alloc_flex - Allocate an object that has a trailing flexible array + * @KMALLOC: kmalloc wrapper function to use for allocation. + * @GFP: GFP flags for the allocation. + * @TYPE: type of structure to allocate space for. + * @FAM: The name of the flexible array member of @TYPE structure. + * @COUNT: how many @FAM elements to allocate space for. + * + * Returns: Newly allocated pointer to @TYPE with @COUNT-many trailing + * @FAM elements, or NULL on failure or if @COUNT cannot be represented + * by the member of @TYPE that counts the @FAM elements (annotated via + * __counted_by()). + */ +#define __alloc_flex(KMALLOC, GFP, TYPE, FAM, COUNT) \ +({ \ + const size_t __count = (COUNT); \ + const size_t __obj_size = struct_size_t(TYPE, FAM, __count); \ + TYPE *__obj_ptr; \ + if (WARN_ON_ONCE(overflows_flex_counter_type(TYPE, FAM, __count))) \ + __obj_ptr = NULL; \ + else \ + __obj_ptr = KMALLOC(__obj_size, GFP); \ + if (__obj_ptr) \ + __set_flex_counter(__obj_ptr->FAM, __count); \ + __obj_ptr; \ +}) + +/** * kmalloc_obj - Allocate a single instance of the given type * @VAR_OR_TYPE: Variable or type to allocate. * @GFP: GFP flags for the allocation. @@ -1005,23 +1032,44 @@ void *kmalloc_nolock_noprof(size_t size, gfp_t gfp_flags, int node); #define kmalloc_objs(VAR_OR_TYPE, COUNT, GFP) \ __alloc_objs(kmalloc, GFP, typeof(VAR_OR_TYPE), COUNT) +/** + * kmalloc_flex - Allocate a single instance of the given flexible structure + * @VAR_OR_TYPE: Variable or type to allocate (with its flex array). + * @FAM: The name of the flexible array member of the structure. + * @COUNT: How many flexible array member elements are desired. + * @GFP: GFP flags for the allocation. + * + * Returns: newly allocated pointer to @VAR_OR_TYPE on success, NULL on + * failure. If @FAM has been annotated with __counted_by(), the allocation + * will immediately fail if @COUNT is larger than what the type of the + * struct's counter variable can represent. + */ +#define kmalloc_flex(VAR_OR_TYPE, FAM, COUNT, GFP) \ + __alloc_flex(kmalloc, GFP, typeof(VAR_OR_TYPE), FAM, COUNT) + /* All kzalloc aliases for kmalloc_(obj|objs|flex). */ #define kzalloc_obj(P, GFP) \ __alloc_objs(kzalloc, GFP, typeof(P), 1) #define kzalloc_objs(P, COUNT, GFP) \ __alloc_objs(kzalloc, GFP, typeof(P), COUNT) +#define kzalloc_flex(P, FAM, COUNT, GFP) \ + __alloc_flex(kzalloc, GFP, typeof(P), FAM, COUNT) /* All kvmalloc aliases for kmalloc_(obj|objs|flex). */ #define kvmalloc_obj(P, GFP) \ __alloc_objs(kvmalloc, GFP, typeof(P), 1) #define kvmalloc_objs(P, COUNT, GFP) \ __alloc_objs(kvmalloc, GFP, typeof(P), COUNT) +#define kvmalloc_flex(P, FAM, COUNT, GFP) \ + __alloc_flex(kvmalloc, GFP, typeof(P), FAM, COUNT) /* All kvzalloc aliases for kmalloc_(obj|objs|flex). */ #define kvzalloc_obj(P, GFP) \ __alloc_objs(kvzalloc, GFP, typeof(P), 1) #define kvzalloc_objs(P, COUNT, GFP) \ __alloc_objs(kvzalloc, GFP, typeof(P), COUNT) +#define kvzalloc_flex(P, FAM, COUNT, GFP) \ + __alloc_flex(kvzalloc, GFP, typeof(P), FAM, COUNT) #define kmem_buckets_alloc(_b, _size, _flags) \ alloc_hooks(__kmalloc_node_noprof(PASS_BUCKET_PARAMS(_size, _b), _flags, NUMA_NO_NODE)) |