FS-Cache: Provide a slab for cookie allocation

Provide a slab from which can be allocated the FS-Cache cookies that will be
presented to the netfs.

Also provide a slab constructor and a function to recursively discard a cookie
and its ancestor chain.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/fs/fscache/main.c b/fs/fscache/main.c
index c2f3e637725d..48b79d2deac1 100644
--- a/fs/fscache/main.c
+++ b/fs/fscache/main.c
@@ -56,6 +56,18 @@ static int __init fscache_init(void)
         if (ret < 0)
                 goto error_proc;
 
+        fscache_cookie_jar = kmem_cache_create("fscache_cookie_jar",
+                                               sizeof(struct fscache_cookie),
+                                               0,
+                                               0,
+                                               fscache_cookie_init_once);
+        if (!fscache_cookie_jar) {
+                printk(KERN_NOTICE
+                       "FS-Cache: Failed to allocate a cookie jar\n");
+                ret = -ENOMEM;
+                goto error_cookie_jar;
+        }
+
         fscache_root = kobject_create_and_add("fscache", kernel_kobj);
         if (!fscache_root)
                 goto error_kobj;
@@ -64,6 +76,8 @@ static int __init fscache_init(void)
         return 0;
 
 error_kobj:
+        kmem_cache_destroy(fscache_cookie_jar);
+error_cookie_jar:
         fscache_proc_cleanup();
 error_proc:
         slow_work_unregister_user();
@@ -81,6 +95,7 @@ static void __exit fscache_exit(void)
         _enter("");
 
         kobject_put(fscache_root);
+        kmem_cache_destroy(fscache_cookie_jar);
         fscache_proc_cleanup();
         slow_work_unregister_user();
         printk(KERN_NOTICE "FS-Cache: Unloaded\n");