[PATCH -next 0/3] configfs: Clean up by adding helpers

[PATCH -next 0/3] configfs: Clean up by adding helpers

[Shang XiaoJing]

Some clean up in dir.c, inode.c, and symlink.c.

Shang XiaoJing (3):
  configfs: Add configfs_remove_drop_dirent helper
  configfs: Add group_to_dentry helper
  configfs: Add subsys_to_item helper

 fs/configfs/configfs_internal.h |  1 +
 fs/configfs/dir.c               | 61 +++++++++++++++++++++------------
 fs/configfs/inode.c             |  6 +---
 fs/configfs/symlink.c           |  6 +---
 4 files changed, 42 insertions(+), 32 deletions(-)

-- 
2.17.1

[PATCH -next 1/3] configfs: Add configfs_remove_drop_dirent helper

[Shang XiaoJing]

Wrap repeated code in helper function configf_remove_drop_dirent, which
remove dirent and drop dentry.

Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
---
 fs/configfs/configfs_internal.h |  1 +
 fs/configfs/dir.c               | 16 +++++++++++-----
 fs/configfs/inode.c             |  6 +-----
 fs/configfs/symlink.c           |  6 +-----
 4 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/fs/configfs/configfs_internal.h b/fs/configfs/configfs_internal.h
index c0395363eab9..4905b6d35dda 100644
--- a/fs/configfs/configfs_internal.h
+++ b/fs/configfs/configfs_internal.h
@@ -76,6 +76,7 @@ extern int configfs_dirent_is_ready(struct configfs_dirent *);
 extern void configfs_hash_and_remove(struct dentry * dir, const char * name);
 
 extern const unsigned char * configfs_get_name(struct configfs_dirent *sd);
+extern void configfs_remove_drop_dirent(struct configfs_dirent *sd, struct dentry *dentry);
 extern void configfs_drop_dentry(struct configfs_dirent *sd, struct dentry *parent);
 extern int configfs_setattr(struct user_namespace *mnt_userns,
 			    struct dentry *dentry, struct iattr *iattr);
diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index d1f9d2632202..4e086635b3ed 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -257,6 +257,16 @@ int configfs_make_dirent(struct configfs_dirent * parent_sd,
 	return 0;
 }
 
+void configfs_remove_drop_dirent(struct configfs_dirent *sd,
+				  struct dentry *dentry)
+{
+	spin_lock(&configfs_dirent_lock);
+	list_del_init(&sd->s_sibling);
+	spin_unlock(&configfs_dirent_lock);
+	configfs_drop_dentry(sd, dentry);
+	configfs_put(sd);
+}
+
 static void configfs_remove_dirent(struct dentry *dentry)
 {
 	struct configfs_dirent *sd = dentry->d_fsdata;
@@ -562,11 +572,7 @@ static void detach_attrs(struct config_item * item)
 	list_for_each_entry_safe(sd, tmp, &parent_sd->s_children, s_sibling) {
 		if (!sd->s_element || !(sd->s_type & CONFIGFS_NOT_PINNED))
 			continue;
-		spin_lock(&configfs_dirent_lock);
-		list_del_init(&sd->s_sibling);
-		spin_unlock(&configfs_dirent_lock);
-		configfs_drop_dentry(sd, dentry);
-		configfs_put(sd);
+		configfs_remove_drop_dirent(sd, dentry);
 	}
 
 	/**
diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c
index b601610e9907..c91fe11e4450 100644
--- a/fs/configfs/inode.c
+++ b/fs/configfs/inode.c
@@ -232,11 +232,7 @@ void configfs_hash_and_remove(struct dentry * dir, const char * name)
 		if (!sd->s_element)
 			continue;
 		if (!strcmp(configfs_get_name(sd), name)) {
-			spin_lock(&configfs_dirent_lock);
-			list_del_init(&sd->s_sibling);
-			spin_unlock(&configfs_dirent_lock);
-			configfs_drop_dentry(sd, dir);
-			configfs_put(sd);
+			configfs_remove_drop_dirent(sd, dir);
 			break;
 		}
 	}
diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c
index 0623c3edcfb9..529d204b807f 100644
--- a/fs/configfs/symlink.c
+++ b/fs/configfs/symlink.c
@@ -233,12 +233,8 @@ int configfs_unlink(struct inode *dir, struct dentry *dentry)
 	parent_item = configfs_get_config_item(dentry->d_parent);
 	type = parent_item->ci_type;
 
-	spin_lock(&configfs_dirent_lock);
-	list_del_init(&sd->s_sibling);
-	spin_unlock(&configfs_dirent_lock);
-	configfs_drop_dentry(sd, dentry->d_parent);
+	configfs_remove_drop_dirent(sd, dentry->d_parent);
 	dput(dentry);
-	configfs_put(sd);
 
 	/*
 	 * drop_link() must be called before
-- 
2.17.1

[PATCH -next 2/3] configfs: Add group_to_dentry helper

[Shang XiaoJing]

Add group_to_dentry helper function for more clear, which get the
corresponding dentry of the config_group.

Space is deleted due to checkpatch.pl.

Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
---
 fs/configfs/dir.c | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index 4e086635b3ed..b5614b66add2 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -611,6 +611,11 @@ static int populate_attrs(struct config_item *item)
 	return error;
 }
 
+static inline struct dentry *group_to_dentry(struct config_group *group)
+{
+	return group->cg_item.ci_dentry;
+}
+
 static int configfs_attach_group(struct config_item *parent_item,
 				 struct config_item *item,
 				 struct dentry *dentry,
@@ -619,7 +624,7 @@ static void configfs_detach_group(struct config_item *item);
 
 static void detach_groups(struct config_group *group)
 {
-	struct dentry * dentry = dget(group->cg_item.ci_dentry);
+	struct dentry *dentry = dget(group_to_dentry(group));
 	struct dentry *child;
 	struct configfs_dirent *parent_sd;
 	struct configfs_dirent *sd, *tmp;
@@ -668,7 +673,7 @@ static int create_default_group(struct config_group *parent_group,
 	int ret;
 	struct configfs_dirent *sd;
 	/* We trust the caller holds a reference to parent */
-	struct dentry *child, *parent = parent_group->cg_item.ci_dentry;
+	struct dentry *child, *parent = group_to_dentry(parent_group);
 
 	if (!group->cg_item.ci_name)
 		group->cg_item.ci_name = group->cg_item.ci_namebuf;
@@ -1225,14 +1230,14 @@ int configfs_depend_item_unlocked(struct configfs_subsystem *caller_subsys,
 		 * additional locking to prevent other subsystem from being
 		 * unregistered
 		 */
-		inode_lock(d_inode(root->cg_item.ci_dentry));
+		inode_lock(d_inode(group_to_dentry(root)));
 
 		/*
 		 * As we are trying to depend item from other subsystem
 		 * we have to check if this subsystem is still registered
 		 */
 		subsys_sd = configfs_find_subsys_dentry(
-				root->cg_item.ci_dentry->d_fsdata,
+				group_to_dentry(root)->d_fsdata,
 				&target_subsys->su_group.cg_item);
 		if (!subsys_sd)
 			goto out_root_unlock;
@@ -1249,7 +1254,7 @@ int configfs_depend_item_unlocked(struct configfs_subsystem *caller_subsys,
 		 * We were called from subsystem other than our target so we
 		 * took some locks so now it's time to release them
 		 */
-		inode_unlock(d_inode(root->cg_item.ci_dentry));
+		inode_unlock(d_inode(group_to_dentry(root)));
 
 	return ret;
 }
@@ -1745,7 +1750,7 @@ int configfs_register_group(struct config_group *parent_group,
 	link_group(parent_group, group);
 	mutex_unlock(&subsys->su_mutex);
 
-	parent = parent_group->cg_item.ci_dentry;
+	parent = group_to_dentry(parent_group);
 
 	inode_lock_nested(d_inode(parent), I_MUTEX_PARENT);
 	ret = create_default_group(parent_group, group, frag);
@@ -1753,7 +1758,7 @@ int configfs_register_group(struct config_group *parent_group,
 		goto err_out;
 
 	spin_lock(&configfs_dirent_lock);
-	configfs_dir_set_ready(group->cg_item.ci_dentry->d_fsdata);
+	configfs_dir_set_ready(group_to_dentry(group)->d_fsdata);
 	spin_unlock(&configfs_dirent_lock);
 	inode_unlock(d_inode(parent));
 	put_fragment(frag);
@@ -1777,7 +1782,7 @@ EXPORT_SYMBOL(configfs_register_group);
 void configfs_unregister_group(struct config_group *group)
 {
 	struct configfs_subsystem *subsys = group->cg_subsys;
-	struct dentry *dentry = group->cg_item.ci_dentry;
+	struct dentry *dentry = group_to_dentry(group);
 	struct dentry *parent = group->cg_item.ci_parent->ci_dentry;
 	struct configfs_dirent *sd = dentry->d_fsdata;
 	struct configfs_fragment *frag = sd->s_frag;
@@ -1913,7 +1918,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
 void configfs_unregister_subsystem(struct configfs_subsystem *subsys)
 {
 	struct config_group *group = &subsys->su_group;
-	struct dentry *dentry = group->cg_item.ci_dentry;
+	struct dentry *dentry = group_to_dentry(group);
 	struct dentry *root = dentry->d_sb->s_root;
 	struct configfs_dirent *sd = dentry->d_fsdata;
 	struct configfs_fragment *frag = sd->s_frag;
-- 
2.17.1

[PATCH -next 3/3] configfs: Add subsys_to_item helper

[Shang XiaoJing]

Add helper function subsys_to_item, which get the corresponding
config_item of the configfs_subsystem.

Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
---
 fs/configfs/dir.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index b5614b66add2..e4386eab3428 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -281,7 +281,7 @@ static void configfs_remove_dirent(struct dentry *dentry)
 
 /**
  *	configfs_create_dir - create a directory for an config_item.
- *	@item:		config_itemwe're creating directory for.
+ *	@item:		config_item we're creating directory for.
  *	@dentry:	config_item's dentry.
  *	@frag:		config_item's fragment.
  *
@@ -616,6 +616,12 @@ static inline struct dentry *group_to_dentry(struct config_group *group)
 	return group->cg_item.ci_dentry;
 }
 
+static inline
+struct config_item *subsys_to_item(struct configfs_subsystem *subsys)
+{
+	return &subsys->su_group.cg_item;
+}
+
 static int configfs_attach_group(struct config_item *parent_item,
 				 struct config_item *item,
 				 struct dentry *dentry,
@@ -1119,7 +1125,7 @@ int configfs_depend_item(struct configfs_subsystem *subsys,
 {
 	int ret;
 	struct configfs_dirent *subsys_sd;
-	struct config_item *s_item = &subsys->su_group.cg_item;
+	struct config_item *s_item = subsys_to_item(subsys);
 	struct dentry *root;
 
 	/*
@@ -1238,11 +1244,11 @@ int configfs_depend_item_unlocked(struct configfs_subsystem *caller_subsys,
 		 */
 		subsys_sd = configfs_find_subsys_dentry(
 				group_to_dentry(root)->d_fsdata,
-				&target_subsys->su_group.cg_item);
+				subsys_to_item(target_subsys));
 		if (!subsys_sd)
 			goto out_root_unlock;
 	} else {
-		subsys_sd = target_subsys->su_group.cg_item.ci_dentry->d_fsdata;
+		subsys_sd = subsys_to_item(target_subsys)->ci_dentry->d_fsdata;
 	}
 
 	/* Now we can execute core of depend item */
@@ -1315,11 +1321,11 @@ static int configfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
 	 * being created.  We don't want to safely pin the new item but
 	 * fail to pin the subsystem it sits under.
 	 */
-	if (!subsys->su_group.cg_item.ci_type) {
+	if (!subsys_to_item(subsys)->ci_type) {
 		ret = -EINVAL;
 		goto out_put;
 	}
-	subsys_owner = subsys->su_group.cg_item.ci_type->ct_owner;
+	subsys_owner = subsys_to_item(subsys)->ci_type->ct_owner;
 	if (!try_module_get(subsys_owner)) {
 		ret = -EINVAL;
 		goto out_put;
@@ -1469,8 +1475,8 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry)
 	}
 
 	/* configfs_mkdir() shouldn't have allowed this */
-	BUG_ON(!subsys->su_group.cg_item.ci_type);
-	subsys_owner = subsys->su_group.cg_item.ci_type->ct_owner;
+	BUG_ON(!subsys_to_item(subsys)->ci_type);
+	subsys_owner = subsys_to_item(subsys)->ci_type->ct_owner;
 
 	/*
 	 * Ensure that no racing symlink() will make detach_prep() fail while
-- 
2.17.1