kernfs: clean up struct kernfs_iattrs

Right now, kernfs_iattrs embeds the whole struct iattr, even though it
doesn't really use half of its fields... This both leads to wasting
space and makes the code look awkward. Let's just list the few fields
we need directly in struct kernfs_iattrs.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
[PM: merged a number of chunks manually due to fuzz]
Signed-off-by: Paul Moore <paul@paul-moore.com>

diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index b84d635..1654d91 100644 (file)
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -795,9 +795,8 @@ int kernfs_add_one(struct kernfs_node *kn)
        /* Update timestamps on the parent */
        ps_iattr = parent->iattr;
        if (ps_iattr) {
-               struct iattr *ps_iattrs = &ps_iattr->ia_iattr;
-               ktime_get_real_ts64(&ps_iattrs->ia_ctime);
-               ps_iattrs->ia_mtime = ps_iattrs->ia_ctime;
+               ktime_get_real_ts64(&ps_iattr->ia_ctime);
+               ps_iattr->ia_mtime = ps_iattr->ia_ctime;
        }
 
        mutex_unlock(&kernfs_mutex);
@@ -1329,9 +1328,8 @@ static void __kernfs_remove(struct kernfs_node *kn)
 
                        /* update timestamps on the parent */
                        if (ps_iattr) {
-                               ktime_get_real_ts64(&ps_iattr->ia_iattr.ia_ctime);
-                               ps_iattr->ia_iattr.ia_mtime =
-                                       ps_iattr->ia_iattr.ia_ctime;
+                               ktime_get_real_ts64(&ps_iattr->ia_ctime);
+                               ps_iattr->ia_mtime = ps_iattr->ia_ctime;
                        }
 
                        kernfs_put(pos);

diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index 0c1fd94..7d30b49 100644 (file)
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -35,7 +35,6 @@ static struct kernfs_iattrs *kernfs_iattrs(struct kernfs_node *kn)
 {
        static DEFINE_MUTEX(iattr_mutex);
        struct kernfs_iattrs *ret;
-       struct iattr *iattrs;
 
        mutex_lock(&iattr_mutex);
 
@@ -45,16 +44,14 @@ static struct kernfs_iattrs *kernfs_iattrs(struct kernfs_node *kn)
        kn->iattr = kmem_cache_zalloc(kernfs_iattrs_cache, GFP_KERNEL);
        if (!kn->iattr)
                goto out_unlock;
-       iattrs = &kn->iattr->ia_iattr;
 
        /* assign default attributes */
-       iattrs->ia_mode = kn->mode;
-       iattrs->ia_uid = GLOBAL_ROOT_UID;
-       iattrs->ia_gid = GLOBAL_ROOT_GID;
+       kn->iattr->ia_uid = GLOBAL_ROOT_UID;
+       kn->iattr->ia_gid = GLOBAL_ROOT_GID;
 
-       ktime_get_real_ts64(&iattrs->ia_atime);
-       iattrs->ia_mtime = iattrs->ia_atime;
-       iattrs->ia_ctime = iattrs->ia_atime;
+       ktime_get_real_ts64(&kn->iattr->ia_atime);
+       kn->iattr->ia_mtime = kn->iattr->ia_atime;
+       kn->iattr->ia_ctime = kn->iattr->ia_atime;
 
        simple_xattrs_init(&kn->iattr->xattrs);
 out_unlock:
@@ -66,29 +63,24 @@ out_unlock:
 int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr)
 {
        struct kernfs_iattrs *attrs;
-       struct iattr *iattrs;
        unsigned int ia_valid = iattr->ia_valid;
 
        attrs = kernfs_iattrs(kn);
        if (!attrs)
                return -ENOMEM;
 
-       iattrs = &attrs->ia_iattr;
-
        if (ia_valid & ATTR_UID)
-               iattrs->ia_uid = iattr->ia_uid;
+               attrs->ia_uid = iattr->ia_uid;
        if (ia_valid & ATTR_GID)
-               iattrs->ia_gid = iattr->ia_gid;
+               attrs->ia_gid = iattr->ia_gid;
        if (ia_valid & ATTR_ATIME)
-               iattrs->ia_atime = iattr->ia_atime;
+               attrs->ia_atime = iattr->ia_atime;
        if (ia_valid & ATTR_MTIME)
-               iattrs->ia_mtime = iattr->ia_mtime;
+               attrs->ia_mtime = iattr->ia_mtime;
        if (ia_valid & ATTR_CTIME)
-               iattrs->ia_ctime = iattr->ia_ctime;
-       if (ia_valid & ATTR_MODE) {
-               umode_t mode = iattr->ia_mode;
-               iattrs->ia_mode = kn->mode = mode;
-       }
+               attrs->ia_ctime = iattr->ia_ctime;
+       if (ia_valid & ATTR_MODE)
+               kn->mode = iattr->ia_mode;
        return 0;
 }
 
@@ -171,14 +163,15 @@ static inline void set_default_inode_attr(struct inode *inode, umode_t mode)
                inode->i_ctime = current_time(inode);
 }
 
-static inline void set_inode_attr(struct inode *inode, struct iattr *iattr)
+static inline void set_inode_attr(struct inode *inode,
+                                 struct kernfs_iattrs *attrs)
 {
        struct super_block *sb = inode->i_sb;
-       inode->i_uid = iattr->ia_uid;
-       inode->i_gid = iattr->ia_gid;
-       inode->i_atime = timespec64_trunc(iattr->ia_atime, sb->s_time_gran);
-       inode->i_mtime = timespec64_trunc(iattr->ia_mtime, sb->s_time_gran);
-       inode->i_ctime = timespec64_trunc(iattr->ia_ctime, sb->s_time_gran);
+       inode->i_uid = attrs->ia_uid;
+       inode->i_gid = attrs->ia_gid;
+       inode->i_atime = timespec64_trunc(attrs->ia_atime, sb->s_time_gran);
+       inode->i_mtime = timespec64_trunc(attrs->ia_mtime, sb->s_time_gran);
+       inode->i_ctime = timespec64_trunc(attrs->ia_ctime, sb->s_time_gran);
 }
 
 static void kernfs_refresh_inode(struct kernfs_node *kn, struct inode *inode)
@@ -191,7 +184,7 @@ static void kernfs_refresh_inode(struct kernfs_node *kn, struct inode *inode)
                 * kernfs_node has non-default attributes get them from
                 * persistent copy in kernfs_node.
                 */
-               set_inode_attr(inode, &attrs->ia_iattr);
+               set_inode_attr(inode, attrs);
                security_inode_notifysecctx(inode, attrs->ia_secdata,
                                            attrs->ia_secdata_len);
        }

diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index 0b7d197..385a5ca 100644 (file)
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -20,7 +20,11 @@
 #include <linux/fs_context.h>
 
 struct kernfs_iattrs {
-       struct iattr            ia_iattr;
+       kuid_t                  ia_uid;
+       kgid_t                  ia_gid;
+       struct timespec64       ia_atime;
+       struct timespec64       ia_mtime;
+       struct timespec64       ia_ctime;
        void                    *ia_secdata;
        u32                     ia_secdata_len;
 

diff --git a/fs/kernfs/symlink.c b/fs/kernfs/symlink.c
index 162f43b..eb46c3a 100644 (file)
--- a/fs/kernfs/symlink.c
+++ b/fs/kernfs/symlink.c
@@ -33,8 +33,8 @@ struct kernfs_node *kernfs_create_link(struct kernfs_node *parent,
        kgid_t gid = GLOBAL_ROOT_GID;
 
        if (target->iattr) {
-               uid = target->iattr->ia_iattr.ia_uid;
-               gid = target->iattr->ia_iattr.ia_gid;
+               uid = target->iattr->ia_uid;
+               gid = target->iattr->ia_gid;
        }
 
        kn = kernfs_new_node(parent, name, S_IFLNK|S_IRWXUGO, uid, gid,