[PATCH 33/41] sysfs, kernfs: introduce sysfs_root_sd

Tejun Heo
2013-11-23T22:25:34Z

Currently, it's assumed that there's a single kernfs hierarchy in the
system anchored at sysfs_root which is defined as a global struct. To
allow other users of kernfs, this will be made dynamic. Introduce a
new global variable sysfs_root_sd which points to &sysfs_root and
convert all &sysfs_root users.

This patch doesn't introduce any behavior difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
---
fs/sysfs/dir.c | 4 ++--
fs/sysfs/mount.c | 8 +++++---
fs/sysfs/symlink.c | 6 +++---
fs/sysfs/sysfs.h | 2 +-
4 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index e5c4e71..2fea501 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -68,7 +68,7 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
if (kobj->parent)
parent_sd = kobj->parent->sd;
else
- parent_sd = &sysfs_root;
+ parent_sd = sysfs_root_sd;

if (!parent_sd)
return -ENOENT;
@@ -134,7 +134,7 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj,

BUG_ON(!sd->s_parent);
new_parent_sd = new_parent_kobj && new_parent_kobj->sd ?
- new_parent_kobj->sd : &sysfs_root;
+ new_parent_kobj->sd : sysfs_root_sd;

return kernfs_rename_ns(sd, new_parent_sd, sd->s_name, new_ns);
}
diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c
index 0c80f03..7cbd1fc 100644
--- a/fs/sysfs/mount.c
+++ b/fs/sysfs/mount.c
@@ -32,7 +32,7 @@ static const struct super_operations sysfs_ops = {
.evict_inode = sysfs_evict_inode,
};

-struct sysfs_dirent sysfs_root = {
+static struct sysfs_dirent sysfs_root = {
.s_name = "",
.s_count = ATOMIC_INIT(1),
.s_flags = SYSFS_DIR,
@@ -40,6 +40,8 @@ struct sysfs_dirent sysfs_root = {
.s_ino = 1,
};

+struct sysfs_dirent *sysfs_root_sd = &sysfs_root;
+
static int sysfs_fill_super(struct super_block *sb)
{
struct inode *inode;
@@ -53,7 +55,7 @@ static int sysfs_fill_super(struct super_block *sb)

/* get root inode, initialize and unlock it */
mutex_lock(&sysfs_mutex);
- inode = sysfs_get_inode(sb, &sysfs_root);
+ inode = sysfs_get_inode(sb, sysfs_root_sd);
mutex_unlock(&sysfs_mutex);
if (!inode) {
pr_debug("sysfs: could not get root inode\n");
@@ -66,7 +68,7 @@ static int sysfs_fill_super(struct super_block *sb)
pr_debug("%s: could not get root dentry!\n", __func__);
return -ENOMEM;
}
- root->d_fsdata = &sysfs_root;
+ root->d_fsdata = sysfs_root_sd;
sb->s_root = root;
sb->s_d_op = &sysfs_dentry_ops;
return 0;
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index 6797c9c..62f0e01 100644
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -70,7 +70,7 @@ static int sysfs_do_create_link(struct kobject *kobj, struct kobject *target,
struct sysfs_dirent *parent_sd = NULL;

if (!kobj)
- parent_sd = &sysfs_root;
+ parent_sd = sysfs_root_sd;
else
parent_sd = kobj->sd;

@@ -144,7 +144,7 @@ void sysfs_remove_link(struct kobject *kobj, const char *name)
struct sysfs_dirent *parent_sd = NULL;

if (!kobj)
- parent_sd = &sysfs_root;
+ parent_sd = sysfs_root_sd;
else
parent_sd = kobj->sd;

@@ -170,7 +170,7 @@ int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *targ,
int result;

if (!kobj)
- parent_sd = &sysfs_root;
+ parent_sd = sysfs_root_sd;
else
parent_sd = kobj->sd;

diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index ce97907..2b217ce 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -28,7 +28,7 @@ struct sysfs_super_info {
const void *ns;
};
#define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))
-extern struct sysfs_dirent sysfs_root;
+extern struct sysfs_dirent *sysfs_root_sd;
extern struct kmem_cache *sysfs_dir_cachep;

/*
--
1.8.4.2