slab: pull kmem_cache_open() into do_kmem_cache_create()

do_kmem_cache_create() is the only caller and we're going to pass down
struct kmem_cache_args in a follow-up patch.
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

mm/slub.c

@@ -5290,65 +5290,6 @@ static int calculate_sizes(struct kmem_cache *s)
 	return !!oo_objects(s->oo);
 }
 
-static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags)
-{
-	s->flags = kmem_cache_flags(flags, s->name);
-#ifdef CONFIG_SLAB_FREELIST_HARDENED
-	s->random = get_random_long();
-#endif
-
-	if (!calculate_sizes(s))
-		goto error;
-	if (disable_higher_order_debug) {
-		/*
-		 * Disable debugging flags that store metadata if the min slab
-		 * order increased.
-		 */
-		if (get_order(s->size) > get_order(s->object_size)) {
-			s->flags &= ~DEBUG_METADATA_FLAGS;
-			s->offset = 0;
-			if (!calculate_sizes(s))
-				goto error;
-		}
-	}
-
-#ifdef system_has_freelist_aba
-	if (system_has_freelist_aba() && !(s->flags & SLAB_NO_CMPXCHG)) {
-		/* Enable fast mode */
-		s->flags |= __CMPXCHG_DOUBLE;
-	}
-#endif
-
-	/*
-	 * The larger the object size is, the more slabs we want on the partial
-	 * list to avoid pounding the page allocator excessively.
-	 */
-	s->min_partial = min_t(unsigned long, MAX_PARTIAL, ilog2(s->size) / 2);
-	s->min_partial = max_t(unsigned long, MIN_PARTIAL, s->min_partial);
-
-	set_cpu_partial(s);
-
-#ifdef CONFIG_NUMA
-	s->remote_node_defrag_ratio = 1000;
-#endif
-
-	/* Initialize the pre-computed randomized freelist if slab is up */
-	if (slab_state >= UP) {
-		if (init_cache_random_seq(s))
-			goto error;
-	}
-
-	if (!init_kmem_cache_nodes(s))
-		goto error;
-
-	if (alloc_kmem_cache_cpus(s))
-		return 0;
-
-error:
-	__kmem_cache_release(s);
-	return -EINVAL;
-}
-
 static void list_slab_objects(struct kmem_cache *s, struct slab *slab,
 			      const char *text)
 {
@@ -5904,26 +5845,77 @@ __kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
 
 int do_kmem_cache_create(struct kmem_cache *s, slab_flags_t flags)
 {
-	int err;
+	int err = -EINVAL;
 
-	err = kmem_cache_open(s, flags);
-	if (err)
-		return err;
+	s->flags = kmem_cache_flags(flags, s->name);
+#ifdef CONFIG_SLAB_FREELIST_HARDENED
+	s->random = get_random_long();
+#endif
+
+	if (!calculate_sizes(s))
+		goto out;
+	if (disable_higher_order_debug) {
+		/*
+		 * Disable debugging flags that store metadata if the min slab
+		 * order increased.
+		 */
+		if (get_order(s->size) > get_order(s->object_size)) {
+			s->flags &= ~DEBUG_METADATA_FLAGS;
+			s->offset = 0;
+			if (!calculate_sizes(s))
+				goto out;
+		}
+	}
+
+#ifdef system_has_freelist_aba
+	if (system_has_freelist_aba() && !(s->flags & SLAB_NO_CMPXCHG)) {
+		/* Enable fast mode */
+		s->flags |= __CMPXCHG_DOUBLE;
+	}
+#endif
+
+	/*
+	 * The larger the object size is, the more slabs we want on the partial
+	 * list to avoid pounding the page allocator excessively.
+	 */
+	s->min_partial = min_t(unsigned long, MAX_PARTIAL, ilog2(s->size) / 2);
+	s->min_partial = max_t(unsigned long, MIN_PARTIAL, s->min_partial);
+
+	set_cpu_partial(s);
+
+#ifdef CONFIG_NUMA
+	s->remote_node_defrag_ratio = 1000;
+#endif
+
+	/* Initialize the pre-computed randomized freelist if slab is up */
+	if (slab_state >= UP) {
+		if (init_cache_random_seq(s))
+			goto out;
+	}
+
+	if (!init_kmem_cache_nodes(s))
+		goto out;
+
+	if (!alloc_kmem_cache_cpus(s))
+		goto out;
 
 	/* Mutex is not taken during early boot */
-	if (slab_state <= UP)
-		return 0;
+	if (slab_state <= UP) {
+		err = 0;
+		goto out;
+	}
 
 	err = sysfs_slab_add(s);
-	if (err) {
-		__kmem_cache_release(s);
-		return err;
-	}
+	if (err)
+		goto out;
 
 	if (s->flags & SLAB_STORE_USER)
 		debugfs_slab_add(s);
 
-	return 0;
+out:
+	if (err)
+		__kmem_cache_release(s);
+	return err;
 }
 
 #ifdef SLAB_SUPPORTS_SYSFS