This is a preparation for the following refactoring of krealloc(), for more efficient function calling as it will call some internal functions defined in slub.c. Signed-off-by: Feng Tang <feng.tang@xxxxxxxxx> --- mm/slab_common.c | 84 ------------------------------------------------ mm/slub.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 84 insertions(+), 84 deletions(-) diff --git a/mm/slab_common.c b/mm/slab_common.c index af6b14769fbd..5734b61a106f 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -1185,90 +1185,6 @@ module_init(slab_proc_init); #endif /* CONFIG_SLUB_DEBUG */ -static __always_inline __realloc_size(2) void * -__do_krealloc(const void *p, size_t new_size, gfp_t flags) -{ - void *ret; - size_t ks; - - /* Check for double-free before calling ksize. */ - if (likely(!ZERO_OR_NULL_PTR(p))) { - if (!kasan_check_byte(p)) - return NULL; - ks = ksize(p); - } else - ks = 0; - - /* If the object still fits, repoison it precisely. */ - if (ks >= new_size) { - /* Zero out spare memory. */ - if (want_init_on_alloc(flags)) { - kasan_disable_current(); - memset((void *)p + new_size, 0, ks - new_size); - kasan_enable_current(); - } - - p = kasan_krealloc((void *)p, new_size, flags); - return (void *)p; - } - - ret = kmalloc_node_track_caller_noprof(new_size, flags, NUMA_NO_NODE, _RET_IP_); - if (ret && p) { - /* Disable KASAN checks as the object's redzone is accessed. */ - kasan_disable_current(); - memcpy(ret, kasan_reset_tag(p), ks); - kasan_enable_current(); - } - - return ret; -} - -/** - * krealloc - reallocate memory. The contents will remain unchanged. - * @p: object to reallocate memory for. - * @new_size: how many bytes of memory are required. - * @flags: the type of memory to allocate. - * - * If @p is %NULL, krealloc() behaves exactly like kmalloc(). If @new_size - * is 0 and @p is not a %NULL pointer, the object pointed to is freed. - * - * If __GFP_ZERO logic is requested, callers must ensure that, starting with the - * initial memory allocation, every subsequent call to this API for the same - * memory allocation is flagged with __GFP_ZERO. Otherwise, it is possible that - * __GFP_ZERO is not fully honored by this API. - * - * This is the case, since krealloc() only knows about the bucket size of an - * allocation (but not the exact size it was allocated with) and hence - * implements the following semantics for shrinking and growing buffers with - * __GFP_ZERO. - * - * new bucket - * 0 size size - * |--------|----------------| - * | keep | zero | - * - * In any case, the contents of the object pointed to are preserved up to the - * lesser of the new and old sizes. - * - * Return: pointer to the allocated memory or %NULL in case of error - */ -void *krealloc_noprof(const void *p, size_t new_size, gfp_t flags) -{ - void *ret; - - if (unlikely(!new_size)) { - kfree(p); - return ZERO_SIZE_PTR; - } - - ret = __do_krealloc(p, new_size, flags); - if (ret && kasan_reset_tag(p) != kasan_reset_tag(ret)) - kfree(p); - - return ret; -} -EXPORT_SYMBOL(krealloc_noprof); - /** * kfree_sensitive - Clear sensitive information in memory before freeing * @p: object to free memory of diff --git a/mm/slub.c b/mm/slub.c index 021991e17287..c1796f9dd30f 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4712,6 +4712,90 @@ void kfree(const void *object) } EXPORT_SYMBOL(kfree); +static __always_inline __realloc_size(2) void * +__do_krealloc(const void *p, size_t new_size, gfp_t flags) +{ + void *ret; + size_t ks; + + /* Check for double-free before calling ksize. */ + if (likely(!ZERO_OR_NULL_PTR(p))) { + if (!kasan_check_byte(p)) + return NULL; + ks = ksize(p); + } else + ks = 0; + + /* If the object still fits, repoison it precisely. */ + if (ks >= new_size) { + /* Zero out spare memory. */ + if (want_init_on_alloc(flags)) { + kasan_disable_current(); + memset((void *)p + new_size, 0, ks - new_size); + kasan_enable_current(); + } + + p = kasan_krealloc((void *)p, new_size, flags); + return (void *)p; + } + + ret = kmalloc_node_track_caller_noprof(new_size, flags, NUMA_NO_NODE, _RET_IP_); + if (ret && p) { + /* Disable KASAN checks as the object's redzone is accessed. */ + kasan_disable_current(); + memcpy(ret, kasan_reset_tag(p), ks); + kasan_enable_current(); + } + + return ret; +} + +/** + * krealloc - reallocate memory. The contents will remain unchanged. + * @p: object to reallocate memory for. + * @new_size: how many bytes of memory are required. + * @flags: the type of memory to allocate. + * + * If @p is %NULL, krealloc() behaves exactly like kmalloc(). If @new_size + * is 0 and @p is not a %NULL pointer, the object pointed to is freed. + * + * If __GFP_ZERO logic is requested, callers must ensure that, starting with the + * initial memory allocation, every subsequent call to this API for the same + * memory allocation is flagged with __GFP_ZERO. Otherwise, it is possible that + * __GFP_ZERO is not fully honored by this API. + * + * This is the case, since krealloc() only knows about the bucket size of an + * allocation (but not the exact size it was allocated with) and hence + * implements the following semantics for shrinking and growing buffers with + * __GFP_ZERO. + * + * new bucket + * 0 size size + * |--------|----------------| + * | keep | zero | + * + * In any case, the contents of the object pointed to are preserved up to the + * lesser of the new and old sizes. + * + * Return: pointer to the allocated memory or %NULL in case of error + */ +void *krealloc_noprof(const void *p, size_t new_size, gfp_t flags) +{ + void *ret; + + if (unlikely(!new_size)) { + kfree(p); + return ZERO_SIZE_PTR; + } + + ret = __do_krealloc(p, new_size, flags); + if (ret && kasan_reset_tag(p) != kasan_reset_tag(ret)) + kfree(p); + + return ret; +} +EXPORT_SYMBOL(krealloc_noprof); + struct detached_freelist { struct slab *slab; void *tail; -- 2.34.1