[PATCH 04/41] sysfs, kernfs: introduce kernfs_remove[_by_name[_ns]]()

[Tejun Heo <tj@kernel.org>]

Introduce kernfs removal interfaces - kernfs_remove() and
kernfs_remove_by_name[_ns]().

These are just renames of sysfs_remove() and sysfs_hash_and_remove().
No functional changes.

v2: Dummy kernfs_remove_by_name_ns() for !CONFIG_SYSFS updated to
    return -ENOSYS instead of 0.

Signed-off-by: Tejun Heo <tj@kernel.org>
---
 fs/sysfs/dir.c         | 20 ++++++++++----------
 fs/sysfs/file.c        |  6 +++---
 fs/sysfs/group.c       | 15 +++++++--------
 fs/sysfs/symlink.c     |  4 ++--
 fs/sysfs/sysfs.h       |  3 ---
 include/linux/kernfs.h | 24 ++++++++++++++++++++++++
 6 files changed, 46 insertions(+), 26 deletions(-)

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 98701c0..edbde4e 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -829,8 +829,8 @@ static struct sysfs_dirent *sysfs_next_descendant_post(struct sysfs_dirent *pos,
 	return pos->s_parent;
 }
 
-static void __sysfs_remove(struct sysfs_addrm_cxt *acxt,
-			   struct sysfs_dirent *sd)
+static void __kernfs_remove(struct sysfs_addrm_cxt *acxt,
+			    struct sysfs_dirent *sd)
 {
 	struct sysfs_dirent *pos, *next;
 
@@ -849,22 +849,22 @@ static void __sysfs_remove(struct sysfs_addrm_cxt *acxt,
 }
 
 /**
- * sysfs_remove - remove a sysfs_dirent recursively
+ * kernfs_remove - remove a sysfs_dirent recursively
  * @sd: the sysfs_dirent to remove
  *
  * Remove @sd along with all its subdirectories and files.
  */
-void sysfs_remove(struct sysfs_dirent *sd)
+void kernfs_remove(struct sysfs_dirent *sd)
 {
 	struct sysfs_addrm_cxt acxt;
 
 	sysfs_addrm_start(&acxt);
-	__sysfs_remove(&acxt, sd);
+	__kernfs_remove(&acxt, sd);
 	sysfs_addrm_finish(&acxt);
 }
 
 /**
- * sysfs_hash_and_remove - find a sysfs_dirent by name and remove it
+ * kernfs_remove_by_name_ns - find a sysfs_dirent by name and remove it
  * @dir_sd: parent of the target
  * @name: name of the sysfs_dirent to remove
  * @ns: namespace tag of the sysfs_dirent to remove
@@ -872,8 +872,8 @@ void sysfs_remove(struct sysfs_dirent *sd)
  * Look for the sysfs_dirent with @name and @ns under @dir_sd and remove
  * it.  Returns 0 on success, -ENOENT if such entry doesn't exist.
  */
-int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name,
-			  const void *ns)
+int kernfs_remove_by_name_ns(struct sysfs_dirent *dir_sd, const char *name,
+			     const void *ns)
 {
 	struct sysfs_addrm_cxt acxt;
 	struct sysfs_dirent *sd;
@@ -888,7 +888,7 @@ int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name,
 
 	sd = sysfs_find_dirent(dir_sd, name, ns);
 	if (sd)
-		__sysfs_remove(&acxt, sd);
+		__kernfs_remove(&acxt, sd);
 
 	sysfs_addrm_finish(&acxt);
 
@@ -928,7 +928,7 @@ void sysfs_remove_dir(struct kobject *kobj)
 
 	if (sd) {
 		WARN_ON_ONCE(sysfs_type(sd) != SYSFS_DIR);
-		sysfs_remove(sd);
+		kernfs_remove(sd);
 	}
 }
 
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index b94f936..6e2ee22 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -970,7 +970,7 @@ void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
 {
 	struct sysfs_dirent *dir_sd = kobj->sd;
 
-	sysfs_hash_and_remove(dir_sd, attr->name, ns);
+	kernfs_remove_by_name_ns(dir_sd, attr->name, ns);
 }
 EXPORT_SYMBOL_GPL(sysfs_remove_file_ns);
 
@@ -998,7 +998,7 @@ void sysfs_remove_file_from_group(struct kobject *kobj,
 	else
 		dir_sd = sysfs_get(kobj->sd);
 	if (dir_sd) {
-		sysfs_hash_and_remove(dir_sd, attr->name, NULL);
+		kernfs_remove_by_name(dir_sd, attr->name);
 		sysfs_put(dir_sd);
 	}
 }
@@ -1026,7 +1026,7 @@ EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
 void sysfs_remove_bin_file(struct kobject *kobj,
 			   const struct bin_attribute *attr)
 {
-	sysfs_hash_and_remove(kobj->sd, attr->attr.name, NULL);
+	kernfs_remove_by_name(kobj->sd, attr->attr.name);
 }
 EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);
 
diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c
index 3796afd..01657c5 100644
--- a/fs/sysfs/group.c
+++ b/fs/sysfs/group.c
@@ -26,7 +26,7 @@ static void remove_files(struct sysfs_dirent *dir_sd, struct kobject *kobj,
 
 	if (grp->attrs)
 		for (attr = grp->attrs; *attr; attr++)
-			sysfs_hash_and_remove(dir_sd, (*attr)->name, NULL);
+			kernfs_remove_by_name(dir_sd, (*attr)->name);
 	if (grp->bin_attrs)
 		for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++)
 			sysfs_remove_bin_file(kobj, *bin_attr);
@@ -49,8 +49,7 @@ static int create_files(struct sysfs_dirent *dir_sd, struct kobject *kobj,
 			 * re-adding (if required) the file.
 			 */
 			if (update)
-				sysfs_hash_and_remove(dir_sd, (*attr)->name,
-						      NULL);
+				kernfs_remove_by_name(dir_sd, (*attr)->name);
 			if (grp->is_visible) {
 				mode = grp->is_visible(kobj, *attr, i);
 				if (!mode)
@@ -111,7 +110,7 @@ static int internal_create_group(struct kobject *kobj, int update,
 	error = create_files(sd, kobj, grp, update);
 	if (error) {
 		if (grp->name)
-			sysfs_remove(sd);
+			kernfs_remove(sd);
 	}
 	sysfs_put(sd);
 	return error;
@@ -228,7 +227,7 @@ void sysfs_remove_group(struct kobject *kobj,
 
 	remove_files(sd, kobj, grp);
 	if (grp->name)
-		sysfs_remove(sd);
+		kernfs_remove(sd);
 
 	sysfs_put(sd);
 }
@@ -279,7 +278,7 @@ int sysfs_merge_group(struct kobject *kobj,
 		error = sysfs_add_file(dir_sd, *attr, SYSFS_KOBJ_ATTR);
 	if (error) {
 		while (--i >= 0)
-			sysfs_hash_and_remove(dir_sd, (*--attr)->name, NULL);
+			kernfs_remove_by_name(dir_sd, (*--attr)->name);
 	}
 	sysfs_put(dir_sd);
 
@@ -301,7 +300,7 @@ void sysfs_unmerge_group(struct kobject *kobj,
 	dir_sd = sysfs_get_dirent(kobj->sd, grp->name);
 	if (dir_sd) {
 		for (attr = grp->attrs; *attr; ++attr)
-			sysfs_hash_and_remove(dir_sd, (*attr)->name, NULL);
+			kernfs_remove_by_name(dir_sd, (*attr)->name);
 		sysfs_put(dir_sd);
 	}
 }
@@ -344,7 +343,7 @@ void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
 
 	dir_sd = sysfs_get_dirent(kobj->sd, group_name);
 	if (dir_sd) {
-		sysfs_hash_and_remove(dir_sd, link_name, NULL);
+		kernfs_remove_by_name(dir_sd, link_name);
 		sysfs_put(dir_sd);
 	}
 }
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index c660363..71583fc 100644
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -153,7 +153,7 @@ void sysfs_delete_link(struct kobject *kobj, struct kobject *targ,
 	if (targ->sd && (kobj->sd->s_flags & SYSFS_FLAG_NS))
 		ns = targ->sd->s_ns;
 	spin_unlock(&sysfs_symlink_target_lock);
-	sysfs_hash_and_remove(kobj->sd, name, ns);
+	kernfs_remove_by_name_ns(kobj->sd, name, ns);
 }
 
 /**
@@ -170,7 +170,7 @@ void sysfs_remove_link(struct kobject *kobj, const char *name)
 	else
 		parent_sd = kobj->sd;
 
-	sysfs_hash_and_remove(parent_sd, name, NULL);
+	kernfs_remove_by_name(parent_sd, name);
 }
 EXPORT_SYMBOL_GPL(sysfs_remove_link);
 
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index e116c21..97625b1 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -173,9 +173,6 @@ int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd,
 		    struct sysfs_dirent *parent_sd);
 int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd,
 		  struct sysfs_dirent *parent_sd);
-void sysfs_remove(struct sysfs_dirent *sd);
-int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name,
-			  const void *ns);
 void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
 
 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h
index 254b9e8..83e151a 100644
--- a/include/linux/kernfs.h
+++ b/include/linux/kernfs.h
@@ -7,6 +7,30 @@
 #ifndef __LINUX_KERNFS_H
 #define __LINUX_KERNFS_H
 
+#include <linux/kernel.h>
+
 struct sysfs_dirent;
 
+#ifdef CONFIG_SYSFS
+
+void kernfs_remove(struct sysfs_dirent *sd);
+int kernfs_remove_by_name_ns(struct sysfs_dirent *parent, const char *name,
+			     const void *ns);
+
+#else	/* CONFIG_SYSFS */
+
+static inline void kernfs_remove(struct sysfs_dirent *sd) { }
+
+static inline int kernfs_remove_by_name_ns(struct sysfs_dirent *parent,
+					   const char *name, const void *ns)
+{ return -ENOSYS; }
+
+#endif	/* CONFIG_SYSFS */
+
+static inline int kernfs_remove_by_name(struct sysfs_dirent *parent,
+					const char *name)
+{
+	return kernfs_remove_by_name_ns(parent, name, NULL);
+}
+
 #endif	/* __LINUX_KERNFS_H */
-- 
1.8.4.2