[PATCH v2 7/7] tracefs: switch to simplefs inode creation API

From: Emanuele Giuseppe Esposito
Date: Tue Apr 21 2020 - 09:58:20 EST


There is no semantic change intended; the code in the libfs.c
functions in fact was derived from debugfs and tracefs code.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@xxxxxxxxxx>
---
fs/tracefs/inode.c | 86 ++++------------------------------------------
1 file changed, 7 insertions(+), 79 deletions(-)

diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c
index 370eb38ff1ad..bceaa4f45da2 100644
--- a/fs/tracefs/inode.c
+++ b/fs/tracefs/inode.c
@@ -308,57 +308,6 @@ static struct file_system_type trace_fs_type = {
};
MODULE_ALIAS_FS("tracefs");

-static struct dentry *start_creating(const char *name, struct dentry *parent)
-{
- struct dentry *dentry;
- int error;
-
- pr_debug("tracefs: creating file '%s'\n",name);
-
- error = simple_pin_fs(&tracefs, &trace_fs_type);
- if (error)
- return ERR_PTR(error);
-
- /* If the parent is not specified, we create it in the root.
- * We need the root dentry to do this, which is in the super
- * block. A pointer to that is in the struct vfsmount that we
- * have around.
- */
- if (!parent)
- parent = tracefs.mount->mnt_root;
-
- inode_lock(parent->d_inode);
- if (unlikely(IS_DEADDIR(parent->d_inode)))
- dentry = ERR_PTR(-ENOENT);
- else
- dentry = lookup_one_len(name, parent, strlen(name));
- if (!IS_ERR(dentry) && dentry->d_inode) {
- dput(dentry);
- dentry = ERR_PTR(-EEXIST);
- }
-
- if (IS_ERR(dentry)) {
- inode_unlock(parent->d_inode);
- simple_release_fs(&tracefs);
- }
-
- return dentry;
-}
-
-static struct dentry *failed_creating(struct dentry *dentry)
-{
- inode_unlock(dentry->d_parent->d_inode);
- dput(dentry);
- simple_release_fs(&tracefs);
- return NULL;
-}
-
-static struct dentry *end_creating(struct dentry *dentry)
-{
- inode_unlock(dentry->d_parent->d_inode);
- return dentry;
-}
-
/**
* tracefs_create_file - create a file in the tracefs filesystem
* @name: a pointer to a string containing the name of the file to create.
@@ -395,49 +344,28 @@ struct dentry *tracefs_create_file(const char *name, umode_t mode,
if (security_locked_down(LOCKDOWN_TRACEFS))
return NULL;

- if (!(mode & S_IFMT))
- mode |= S_IFREG;
- BUG_ON(!S_ISREG(mode));
- dentry = start_creating(name, parent);
-
+ dentry = simplefs_create_file(&tracefs, &trace_fs_type,
+ name, mode, parent, data, &inode);
if (IS_ERR(dentry))
return NULL;

- inode = tracefs_get_inode(dentry->d_sb);
- if (unlikely(!inode))
- return failed_creating(dentry);
-
- inode->i_mode = mode;
inode->i_fop = fops ? fops : &tracefs_file_operations;
- inode->i_private = data;
- d_instantiate(dentry, inode);
- fsnotify_create(dentry->d_parent->d_inode, dentry);
- return end_creating(dentry);
+ return simplefs_finish_dentry(dentry, inode);
}

static struct dentry *__create_dir(const char *name, struct dentry *parent,
const struct inode_operations *ops)
{
- struct dentry *dentry = start_creating(name, parent);
+ struct dentry *dentry;
struct inode *inode;

+ dentry = simplefs_create_dir(&tracefs, &trace_fs_type,
+ name, 0755, parent, &inode);
if (IS_ERR(dentry))
return NULL;

- inode = tracefs_get_inode(dentry->d_sb);
- if (unlikely(!inode))
- return failed_creating(dentry);
-
- inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
inode->i_op = ops;
- inode->i_fop = &simple_dir_operations;
-
- /* directory inodes start off with i_nlink == 2 (for "." entry) */
- inc_nlink(inode);
- d_instantiate(dentry, inode);
- inc_nlink(dentry->d_parent->d_inode);
- fsnotify_mkdir(dentry->d_parent->d_inode, dentry);
- return end_creating(dentry);
+ return simplefs_finish_dentry(dentry, inode);
}

/**
--
2.25.2