ima: initialize ima before inodes can be allocated

ima wants to create an inode information struct (iint) when inodes are
allocated. This means that at least the part of ima which does this
allocation (the allocation is filled with information later) should
before any inodes are created. To accomplish this we split the ima
initialization routine placing the kmem cache allocator inside a
security_initcall() function. Since this makes use of radix trees we also
need to make sure that is initialized before security_initcall().

Signed-off-by: Eric Paris <[e-mail]>
Acked-by: Mimi Zohar <[e-mail]>
Signed-off-by: Al Viro <[e-mail]>

init/main.c

···
 	proc_caches_init();
 	buffer_init();
 	key_init();
+	radix_tree_init();
 	security_init();
 	vfs_caches_init(totalram_pages);
-	radix_tree_init();
 	signals_init();
 	/* rootfs populating might need page-writeback */
 	page_writeback_init();

security/integrity/ima/ima.h

···
 			 const char *cause, int result, int info);
 
 /* Internal IMA function definitions */
-void ima_iintcache_init(void);
 int ima_init(void);
 void ima_cleanup(void);
 int ima_fs_init(void);

security/integrity/ima/ima_iint.c

···
 	struct ima_iint_cache *iint = NULL;
 	int rc = 0;
 
-	if (!ima_initialized)
-		return 0;
-
 	iint = kmem_cache_alloc(iint_cache, GFP_NOFS);
 	if (!iint)
 		return -ENOMEM;
···
 {
 	struct ima_iint_cache *iint;
 
-	if (!ima_initialized)
-		return;
 	spin_lock(&ima_iint_lock);
 	iint = radix_tree_delete(&ima_iint_store, (unsigned long)inode);
 	spin_unlock(&ima_iint_lock);
···
 	kref_set(&iint->refcount, 1);
 }
 
-void __init ima_iintcache_init(void)
+static int __init ima_iintcache_init(void)
 {
 	iint_cache =
 	    kmem_cache_create("iint_cache", sizeof(struct ima_iint_cache), 0,
 			      SLAB_PANIC, init_once);
+	return 0;
 }
+security_initcall(ima_iintcache_init);

security/integrity/ima/ima_main.c

···
 {
 	int error;
 
-	ima_iintcache_init();
 	error = ima_init();
 	ima_initialized = 1;
 	return error;