diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/slab.c | 2 | ||||
| -rw-r--r-- | mm/slab.h | 5 | ||||
| -rw-r--r-- | mm/slab_common.c | 46 | ||||
| -rw-r--r-- | mm/slub.c | 11 |
4 files changed, 52 insertions, 12 deletions
diff --git a/mm/slab.c b/mm/slab.c index b2beb2cc15e2..47acfe54e1ae 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1281,7 +1281,7 @@ void __init kmem_cache_init(void) create_boot_cache(kmem_cache, "kmem_cache", offsetof(struct kmem_cache, node) + nr_node_ids * sizeof(struct kmem_cache_node *), - SLAB_HWCACHE_ALIGN); + SLAB_HWCACHE_ALIGN, 0, 0); list_add(&kmem_cache->list, &slab_caches); slab_state = PARTIAL; diff --git a/mm/slab.h b/mm/slab.h index ad657ffa44e5..8f3030788e01 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -22,6 +22,8 @@ struct kmem_cache { unsigned int size; /* The aligned/padded/added on size */ unsigned int align; /* Alignment as calculated */ slab_flags_t flags; /* Active flags on the slab */ + size_t useroffset; /* Usercopy region offset */ + size_t usersize; /* Usercopy region size */ const char *name; /* Slab name for sysfs */ int refcount; /* Use counter */ void (*ctor)(void *); /* Called on object slot creation */ @@ -97,7 +99,8 @@ int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags); extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size, slab_flags_t flags); extern void create_boot_cache(struct kmem_cache *, const char *name, - size_t size, slab_flags_t flags); + size_t size, slab_flags_t flags, size_t useroffset, + size_t usersize); int slab_unmergeable(struct kmem_cache *s); struct kmem_cache *find_mergeable(size_t size, size_t align, diff --git a/mm/slab_common.c b/mm/slab_common.c index c8cb36774ba1..fc3e66bdce75 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -281,6 +281,9 @@ int slab_unmergeable(struct kmem_cache *s) if (s->ctor) return 1; + if (s->usersize) + return 1; + /* * We may have set a slab to be unmergeable during bootstrap. */ @@ -366,12 +369,16 @@ unsigned long calculate_alignment(slab_flags_t flags, static struct kmem_cache *create_cache(const char *name, size_t object_size, size_t size, size_t align, - slab_flags_t flags, void (*ctor)(void *), + slab_flags_t flags, size_t useroffset, + size_t usersize, void (*ctor)(void *), struct mem_cgroup *memcg, struct kmem_cache *root_cache) { struct kmem_cache *s; int err; + if (WARN_ON(useroffset + usersize > object_size)) + useroffset = usersize = 0; + err = -ENOMEM; s = kmem_cache_zalloc(kmem_cache, GFP_KERNEL); if (!s) @@ -382,6 +389,8 @@ static struct kmem_cache *create_cache(const char *name, s->size = size; s->align = align; s->ctor = ctor; + s->useroffset = useroffset; + s->usersize = usersize; err = init_memcg_params(s, memcg, root_cache); if (err) @@ -406,11 +415,13 @@ out_free_cache: } /* - * kmem_cache_create - Create a cache. + * kmem_cache_create_usercopy - Create a cache. * @name: A string which is used in /proc/slabinfo to identify this cache. * @size: The size of objects to be created in this cache. * @align: The required alignment for the objects. * @flags: SLAB flags + * @useroffset: Usercopy region offset + * @usersize: Usercopy region size * @ctor: A constructor for the objects. * * Returns a ptr to the cache on success, NULL on failure. @@ -430,8 +441,9 @@ out_free_cache: * as davem. */ struct kmem_cache * -kmem_cache_create(const char *name, size_t size, size_t align, - slab_flags_t flags, void (*ctor)(void *)) +kmem_cache_create_usercopy(const char *name, size_t size, size_t align, + slab_flags_t flags, size_t useroffset, size_t usersize, + void (*ctor)(void *)) { struct kmem_cache *s = NULL; const char *cache_name; @@ -462,7 +474,13 @@ kmem_cache_create(const char *name, size_t size, size_t align, */ flags &= CACHE_CREATE_MASK; - s = __kmem_cache_alias(name, size, align, flags, ctor); + /* Fail closed on bad usersize of useroffset values. */ + if (WARN_ON(!usersize && useroffset) || + WARN_ON(size < usersize || size - usersize < useroffset)) + usersize = useroffset = 0; + + if (!usersize) + s = __kmem_cache_alias(name, size, align, flags, ctor); if (s) goto out_unlock; @@ -474,7 +492,7 @@ kmem_cache_create(const char *name, size_t size, size_t align, s = create_cache(cache_name, size, size, calculate_alignment(flags, align, size), - flags, ctor, NULL, NULL); + flags, useroffset, usersize, ctor, NULL, NULL); if (IS_ERR(s)) { err = PTR_ERR(s); kfree_const(cache_name); @@ -500,6 +518,15 @@ out_unlock: } return s; } +EXPORT_SYMBOL(kmem_cache_create_usercopy); + +struct kmem_cache * +kmem_cache_create(const char *name, size_t size, size_t align, + slab_flags_t flags, void (*ctor)(void *)) +{ + return kmem_cache_create_usercopy(name, size, align, flags, 0, size, + ctor); +} EXPORT_SYMBOL(kmem_cache_create); static void slab_caches_to_rcu_destroy_workfn(struct work_struct *work) @@ -612,6 +639,7 @@ void memcg_create_kmem_cache(struct mem_cgroup *memcg, s = create_cache(cache_name, root_cache->object_size, root_cache->size, root_cache->align, root_cache->flags & CACHE_CREATE_MASK, + root_cache->useroffset, root_cache->usersize, root_cache->ctor, memcg, root_cache); /* * If we could not create a memcg cache, do not complain, because @@ -879,13 +907,15 @@ bool slab_is_available(void) #ifndef CONFIG_SLOB /* Create a cache during boot when no slab services are available yet */ void __init create_boot_cache(struct kmem_cache *s, const char *name, size_t size, - slab_flags_t flags) + slab_flags_t flags, size_t useroffset, size_t usersize) { int err; s->name = name; s->size = s->object_size = size; s->align = calculate_alignment(flags, ARCH_KMALLOC_MINALIGN, size); + s->useroffset = useroffset; + s->usersize = usersize; slab_init_memcg_params(s); @@ -906,7 +936,7 @@ struct kmem_cache *__init create_kmalloc_cache(const char *name, size_t size, if (!s) panic("Out of memory when creating slab %s\n", name); - create_boot_cache(s, name, size, flags); + create_boot_cache(s, name, size, flags, 0, size); list_add(&s->list, &slab_caches); memcg_link_cache(s); s->refcount = 1; diff --git a/mm/slub.c b/mm/slub.c index bcd22332300a..f40a57164dd6 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4183,7 +4183,7 @@ void __init kmem_cache_init(void) kmem_cache = &boot_kmem_cache; create_boot_cache(kmem_cache_node, "kmem_cache_node", - sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN); + sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN, 0, 0); register_hotmemory_notifier(&slab_memory_callback_nb); @@ -4193,7 +4193,7 @@ void __init kmem_cache_init(void) create_boot_cache(kmem_cache, "kmem_cache", offsetof(struct kmem_cache, node) + nr_node_ids * sizeof(struct kmem_cache_node *), - SLAB_HWCACHE_ALIGN); + SLAB_HWCACHE_ALIGN, 0, 0); kmem_cache = bootstrap(&boot_kmem_cache); @@ -5063,6 +5063,12 @@ static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) SLAB_ATTR_RO(cache_dma); #endif +static ssize_t usersize_show(struct kmem_cache *s, char *buf) +{ + return sprintf(buf, "%zu\n", s->usersize); +} +SLAB_ATTR_RO(usersize); + static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) { return sprintf(buf, "%d\n", !!(s->flags & SLAB_TYPESAFE_BY_RCU)); @@ -5437,6 +5443,7 @@ static struct attribute *slab_attrs[] = { #ifdef CONFIG_FAILSLAB &failslab_attr.attr, #endif + &usersize_attr.attr, NULL }; |