Author: wulf Date: Sat Aug 29 19:26:31 2020 New Revision: 364964 URL: https://svnweb.freebsd.org/changeset/base/364964
Log: LinuxKPI: Implement ksize() function. In Linux, ksize() gets the actual amount of memory allocated for a given object. This commit adds malloc_usable_size() to FreeBSD KPI which does the same. It also maps LinuxKPI ksize() to newly created function. ksize() function is used by drm-kmod. Reviewed by: hselasky, kib MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D26215 Modified: head/share/man/man9/malloc.9 head/sys/compat/linuxkpi/common/include/linux/slab.h head/sys/kern/kern_malloc.c head/sys/sys/malloc.h head/sys/vm/memguard.c head/sys/vm/memguard.h Modified: head/share/man/man9/malloc.9 ============================================================================== --- head/share/man/man9/malloc.9 Sat Aug 29 18:11:37 2020 (r364963) +++ head/share/man/man9/malloc.9 Sat Aug 29 19:26:31 2020 (r364964) @@ -29,7 +29,7 @@ .\" $NetBSD: malloc.9,v 1.3 1996/11/11 00:05:11 lukem Exp $ .\" $FreeBSD$ .\" -.Dd August 3, 2020 +.Dd August 28, 2020 .Dt MALLOC 9 .Os .Sh NAME @@ -55,6 +55,8 @@ .Fn realloc "void *addr" "size_t size" "struct malloc_type *type" "int flags" .Ft void * .Fn reallocf "void *addr" "size_t size" "struct malloc_type *type" "int flags" +.Ft size_t +.Fn malloc_usable_size "const void *addr" .Fn MALLOC_DECLARE type .In sys/param.h .In sys/malloc.h @@ -149,6 +151,13 @@ function is identical to .Fn realloc except that it will free the passed pointer when the requested memory cannot be allocated. +.Pp +The +.Fn malloc_usable_size +function returns the usable size of the allocation pointed to by +.Fa addr . +The return value may be larger than the size that was requested during +allocation. .Pp Unlike its standard C library counterpart .Pq Xr malloc 3 , Modified: head/sys/compat/linuxkpi/common/include/linux/slab.h ============================================================================== --- head/sys/compat/linuxkpi/common/include/linux/slab.h Sat Aug 29 18:11:37 2020 (r364963) +++ head/sys/compat/linuxkpi/common/include/linux/slab.h Sat Aug 29 19:26:31 2020 (r364964) @@ -154,6 +154,12 @@ kfree(const void *ptr) free(__DECONST(void *, ptr), M_KMALLOC); } +static inline size_t +ksize(const void *ptr) +{ + return (malloc_usable_size(ptr)); +} + extern struct linux_kmem_cache *linux_kmem_cache_create(const char *name, size_t size, size_t align, unsigned flags, linux_kmem_ctor_t *ctor); Modified: head/sys/kern/kern_malloc.c ============================================================================== --- head/sys/kern/kern_malloc.c Sat Aug 29 18:11:37 2020 (r364963) +++ head/sys/kern/kern_malloc.c Sat Aug 29 19:26:31 2020 (r364964) @@ -938,6 +938,42 @@ reallocf(void *addr, size_t size, struct malloc_type * return (mem); } +/* + * malloc_usable_size: returns the usable size of the allocation. + */ +size_t +malloc_usable_size(const void *addr) +{ +#ifndef DEBUG_REDZONE + uma_zone_t zone; + uma_slab_t slab; +#endif + u_long size; + + if (addr == NULL) + return (0); + +#ifdef DEBUG_MEMGUARD + if (is_memguard_addr(__DECONST(void *, addr))) + return (memguard_get_req_size(addr)); +#endif + +#ifdef DEBUG_REDZONE + size = redzone_get_size(__DECONST(void *, addr)); +#else + vtozoneslab((vm_offset_t)addr & (~UMA_SLAB_MASK), &zone, &slab); + if (slab == NULL) + panic("malloc_usable_size: address %p(%p) is not allocated.\n", + addr, (void *)((u_long)addr & (~UMA_SLAB_MASK))); + + if (!malloc_large_slab(slab)) + size = zone->uz_size; + else + size = malloc_large_size(slab); +#endif + return (size); +} + CTASSERT(VM_KMEM_SIZE_SCALE >= 1); /* Modified: head/sys/sys/malloc.h ============================================================================== --- head/sys/sys/malloc.h Sat Aug 29 18:11:37 2020 (r364963) +++ head/sys/sys/malloc.h Sat Aug 29 19:26:31 2020 (r364964) @@ -244,6 +244,7 @@ void malloc_type_allocated(struct malloc_type *type, u void malloc_type_freed(struct malloc_type *type, unsigned long size); void malloc_type_list(malloc_type_list_func_t *, void *); void malloc_uninit(void *); +size_t malloc_usable_size(const void *); void *realloc(void *addr, size_t size, struct malloc_type *type, int flags) __result_use_check __alloc_size(2); void *reallocf(void *addr, size_t size, struct malloc_type *type, int flags) Modified: head/sys/vm/memguard.c ============================================================================== --- head/sys/vm/memguard.c Sat Aug 29 18:11:37 2020 (r364963) +++ head/sys/vm/memguard.c Sat Aug 29 19:26:31 2020 (r364964) @@ -504,3 +504,9 @@ memguard_cmp_zone(uma_zone_t zone) */ return (strcmp(zone->uz_name, vm_memguard_desc) == 0); } + +unsigned long +memguard_get_req_size(const void *addr) +{ + return (*v2sizep(trunc_page((uintptr_t)addr))); +} Modified: head/sys/vm/memguard.h ============================================================================== --- head/sys/vm/memguard.h Sat Aug 29 18:11:37 2020 (r364963) +++ head/sys/vm/memguard.h Sat Aug 29 19:26:31 2020 (r364964) @@ -43,6 +43,7 @@ void memguard_init(struct vmem *); void *memguard_alloc(unsigned long, int); void *memguard_realloc(void *, unsigned long, struct malloc_type *, int); void memguard_free(void *); +unsigned long memguard_get_req_size(const void *); int memguard_cmp_mtp(struct malloc_type *, unsigned long); int memguard_cmp_zone(uma_zone_t); int is_memguard_addr(void *); @@ -52,6 +53,7 @@ int is_memguard_addr(void *); #define memguard_alloc(size, flags) NULL #define memguard_realloc(a, s, mtp, f) NULL #define memguard_free(addr) do { } while (0) +#define memguard_get_req_size(addr) 0 #define memguard_cmp_mtp(mtp, size) 0 #define memguard_cmp_zone(zone) 0 #define is_memguard_addr(addr) 0 _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
