From b130ed5998e62879a66bad08931a2b5e832da95c Mon Sep 17 00:00:00 2001 From: Kinglong Mee Date: Wed, 4 Nov 2015 15:20:24 +0000 Subject: [PATCH] FS-Cache: Don't override netfs's primary_index if registering failed Only override netfs->primary_index when registering success. Cc: stable@vger.kernel.org # v2.6.30+ Signed-off-by: Kinglong Mee Signed-off-by: David Howells Signed-off-by: Al Viro --- fs/fscache/netfs.c | 35 +++++++++++++++++------------------ 1 file changed, 17 insertions(+), 18 deletions(-) diff --git a/fs/fscache/netfs.c b/fs/fscache/netfs.c index 458cc968d9a0..9b28649df3a1 100644 --- a/fs/fscache/netfs.c +++ b/fs/fscache/netfs.c @@ -22,6 +22,7 @@ static LIST_HEAD(fscache_netfs_list); int __fscache_register_netfs(struct fscache_netfs *netfs) { struct fscache_netfs *ptr; + struct fscache_cookie *cookie; int ret; _enter("{%s}", netfs->name); @@ -29,26 +30,25 @@ int __fscache_register_netfs(struct fscache_netfs *netfs) INIT_LIST_HEAD(&netfs->link); /* allocate a cookie for the primary index */ - netfs->primary_index = - kmem_cache_zalloc(fscache_cookie_jar, GFP_KERNEL); + cookie = kmem_cache_zalloc(fscache_cookie_jar, GFP_KERNEL); - if (!netfs->primary_index) { + if (!cookie) { _leave(" = -ENOMEM"); return -ENOMEM; } /* initialise the primary index cookie */ - atomic_set(&netfs->primary_index->usage, 1); - atomic_set(&netfs->primary_index->n_children, 0); - atomic_set(&netfs->primary_index->n_active, 1); + atomic_set(&cookie->usage, 1); + atomic_set(&cookie->n_children, 0); + atomic_set(&cookie->n_active, 1); - netfs->primary_index->def = &fscache_fsdef_netfs_def; - netfs->primary_index->parent = &fscache_fsdef_index; - netfs->primary_index->netfs_data = netfs; - netfs->primary_index->flags = 1 << FSCACHE_COOKIE_ENABLED; + cookie->def = &fscache_fsdef_netfs_def; + cookie->parent = &fscache_fsdef_index; + cookie->netfs_data = netfs; + cookie->flags = 1 << FSCACHE_COOKIE_ENABLED; - spin_lock_init(&netfs->primary_index->lock); - INIT_HLIST_HEAD(&netfs->primary_index->backing_objects); + spin_lock_init(&cookie->lock); + INIT_HLIST_HEAD(&cookie->backing_objects); /* check the netfs type is not already present */ down_write(&fscache_addremove_sem); @@ -59,9 +59,10 @@ int __fscache_register_netfs(struct fscache_netfs *netfs) goto already_registered; } - atomic_inc(&netfs->primary_index->parent->usage); - atomic_inc(&netfs->primary_index->parent->n_children); + atomic_inc(&cookie->parent->usage); + atomic_inc(&cookie->parent->n_children); + netfs->primary_index = cookie; list_add(&netfs->link, &fscache_netfs_list); ret = 0; @@ -70,10 +71,8 @@ int __fscache_register_netfs(struct fscache_netfs *netfs) already_registered: up_write(&fscache_addremove_sem); - if (ret < 0) { - kmem_cache_free(fscache_cookie_jar, netfs->primary_index); - netfs->primary_index = NULL; - } + if (ret < 0) + kmem_cache_free(fscache_cookie_jar, cookie); _leave(" = %d", ret); return ret;