Author: wulf Date: Sun Sep 6 17:40:35 2020 New Revision: 365383 URL: https://svnweb.freebsd.org/changeset/base/365383
Log: MFC r364964: 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 Differential Revision: https://reviews.freebsd.org/D26215 Modified: stable/12/share/man/man9/malloc.9 stable/12/sys/compat/linuxkpi/common/include/linux/slab.h stable/12/sys/kern/kern_malloc.c stable/12/sys/sys/malloc.h stable/12/sys/vm/memguard.c stable/12/sys/vm/memguard.h Directory Properties: stable/12/ (props changed) Modified: stable/12/share/man/man9/malloc.9 ============================================================================== --- stable/12/share/man/man9/malloc.9 Sun Sep 6 15:44:09 2020 (r365382) +++ stable/12/share/man/man9/malloc.9 Sun Sep 6 17:40:35 2020 (r365383) @@ -29,7 +29,7 @@ .\" $NetBSD: malloc.9,v 1.3 1996/11/11 00:05:11 lukem Exp $ .\" $FreeBSD$ .\" -.Dd October 30, 2018 +.Dd August 28, 2020 .Dt MALLOC 9 .Os .Sh NAME @@ -53,6 +53,8 @@ .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 @@ -138,6 +140,13 @@ 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: stable/12/sys/compat/linuxkpi/common/include/linux/slab.h ============================================================================== --- stable/12/sys/compat/linuxkpi/common/include/linux/slab.h Sun Sep 6 15:44:09 2020 (r365382) +++ stable/12/sys/compat/linuxkpi/common/include/linux/slab.h Sun Sep 6 17:40:35 2020 (r365383) @@ -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: stable/12/sys/kern/kern_malloc.c ============================================================================== --- stable/12/sys/kern/kern_malloc.c Sun Sep 6 15:44:09 2020 (r365382) +++ stable/12/sys/kern/kern_malloc.c Sun Sep 6 17:40:35 2020 (r365383) @@ -867,6 +867,41 @@ 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_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 + slab = vtoslab((vm_offset_t)addr & (~UMA_SLAB_MASK)); + if (slab == NULL) + panic("malloc_usable_size: address %p(%p) is not allocated.\n", + addr, (void *)((u_long)addr & (~UMA_SLAB_MASK))); + + if (!(slab->us_flags & UMA_SLAB_MALLOC)) + size = slab->us_keg->uk_size; + else + size = slab->us_size; +#endif + return (size); +} + #ifndef __sparc64__ CTASSERT(VM_KMEM_SIZE_SCALE >= 1); #endif Modified: stable/12/sys/sys/malloc.h ============================================================================== --- stable/12/sys/sys/malloc.h Sun Sep 6 15:44:09 2020 (r365382) +++ stable/12/sys/sys/malloc.h Sun Sep 6 17:40:35 2020 (r365383) @@ -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: stable/12/sys/vm/memguard.c ============================================================================== --- stable/12/sys/vm/memguard.c Sun Sep 6 15:44:09 2020 (r365382) +++ stable/12/sys/vm/memguard.c Sun Sep 6 17:40:35 2020 (r365383) @@ -503,3 +503,9 @@ 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: stable/12/sys/vm/memguard.h ============================================================================== --- stable/12/sys/vm/memguard.h Sun Sep 6 15:44:09 2020 (r365382) +++ stable/12/sys/vm/memguard.h Sun Sep 6 17:40:35 2020 (r365383) @@ -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"
