Commit 93b2b8e4 authored by Tejun Heo's avatar Tejun Heo Committed by Greg Kroah-Hartman
Browse files

sysfs, kernfs: introduce kernfs_create_dir[_ns]() 



Introduce kernfs interface to manipulate a directory which takes and
returns sysfs_dirents.

create_dir() is renamed to kernfs_create_dir_ns() and its argumantes
and return value are updated.  create_dir() usages are replaced with
kernfs_create_dir_ns() and sysfs_create_subdir() usages are replaced
with kernfs_create_dir().  Dup warnings are handled explicitly by
sysfs users of the kernfs interface.

sysfs_enable_ns() is renamed to kernfs_enable_ns().

This patch doesn't introduce any behavior changes.

v2: Dummy implementation for !CONFIG_SYSFS updated to return -ENOSYS.

v3: kernfs_enable_ns() added.

v4: Refreshed on top of "sysfs: drop kobj_ns_type handling, take #2"
    so that this patch removes sysfs_enable_ns().

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 7c6e2d36

fs/sysfs/dir.c

+30 −24
Original line number Diff line number Diff line
@@ -666,9 +666,18 @@ struct sysfs_dirent *sysfs_get_dirent_ns(struct sysfs_dirent *parent_sd, 
}

EXPORT_SYMBOL_GPL(sysfs_get_dirent_ns);



static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,

		      const char *name, const void *ns,

		      struct sysfs_dirent **p_sd)

/**

 * kernfs_create_dir_ns - create a directory

 * @parent: parent in which to create a new directory

 * @name: name of the new directory

 * @priv: opaque data associated with the new directory

 * @ns: optional namespace tag of the directory

 *

 * Returns the created node on success, ERR_PTR() value on failure.

 */

struct sysfs_dirent *kernfs_create_dir_ns(struct sysfs_dirent *parent,

					  const char *name, void *priv,

					  const void *ns)

{

	umode_t mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;

	struct sysfs_addrm_cxt acxt;
@@ -678,28 +687,21 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, 
	/* allocate */

	sd = sysfs_new_dirent(name, mode, SYSFS_DIR);

	if (!sd)

		return -ENOMEM;

		return ERR_PTR(-ENOMEM);



	sd->s_ns = ns;

	sd->priv = kobj;

	sd->priv = priv;



	/* link in */

	sysfs_addrm_start(&acxt);

	rc = sysfs_add_one(&acxt, sd, parent_sd);

	rc = __sysfs_add_one(&acxt, sd, parent);

	sysfs_addrm_finish(&acxt);



	if (rc == 0)

		*p_sd = sd;

	else

		sysfs_put(sd);



	return rc;

}

	if (!rc)

		return sd;



int sysfs_create_subdir(struct kobject *kobj, const char *name,

			struct sysfs_dirent **p_sd)

{

	return create_dir(kobj, kobj->sd, name, NULL, p_sd);

	sysfs_put(sd);

	return ERR_PTR(rc);

}



/**
@@ -710,7 +712,6 @@ int sysfs_create_subdir(struct kobject *kobj, const char *name, 
int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)

{

	struct sysfs_dirent *parent_sd, *sd;

	int error = 0;



	BUG_ON(!kobj);
@@ -722,10 +723,15 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) 
	if (!parent_sd)

		return -ENOENT;



	error = create_dir(kobj, parent_sd, kobject_name(kobj), ns, &sd);

	if (!error)

	sd = kernfs_create_dir_ns(parent_sd, kobject_name(kobj), kobj, ns);

	if (IS_ERR(sd)) {

		if (PTR_ERR(sd) == -EEXIST)

			sysfs_warn_dup(parent_sd, kobject_name(kobj));

		return PTR_ERR(sd);

	}



	kobj->sd = sd;

	return error;

	return 0;

}



static struct dentry *sysfs_lookup(struct inode *dir, struct dentry *dentry,
@@ -1005,14 +1011,14 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, 
}



/**

 * sysfs_enable_ns - enable namespace under a directory

 * kernfs_enable_ns - enable namespace under a directory

 * @sd: directory of interest, should be empty

 *

 * This is to be called right after @sd is created to enable namespace

 * under it.  All children of @sd must have non-NULL namespace tags and

 * only the ones which match the super_block's tag will be visible.

 */

void sysfs_enable_ns(struct sysfs_dirent *sd)

void kernfs_enable_ns(struct sysfs_dirent *sd)

{

	WARN_ON_ONCE(sysfs_type(sd) != SYSFS_DIR);

	WARN_ON_ONCE(!RB_EMPTY_ROOT(&sd->s_dir.children));

fs/sysfs/group.c

+6 −3
Original line number Diff line number Diff line
@@ -101,9 +101,12 @@ static int internal_create_group(struct kobject *kobj, int update, 
		return -EINVAL;

	}

	if (grp->name) {

		error = sysfs_create_subdir(kobj, grp->name, &sd);

		if (error)

			return error;

		sd = kernfs_create_dir(kobj->sd, grp->name, kobj);

		if (IS_ERR(sd)) {

			if (PTR_ERR(sd) == -EEXIST)

				sysfs_warn_dup(kobj->sd, grp->name);

			return PTR_ERR(sd);

		}

	} else

		sd = kobj->sd;

	sysfs_get(sd);

fs/sysfs/sysfs.h

+0 −3
Original line number Diff line number Diff line
@@ -179,9 +179,6 @@ struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type); 


void release_sysfs_dirent(struct sysfs_dirent *sd);



int sysfs_create_subdir(struct kobject *kobj, const char *name,

			struct sysfs_dirent **p_sd);



static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd)

{

	if (sd) {

include/linux/kernfs.h

+17 −0
Original line number Diff line number Diff line
@@ -17,6 +17,9 @@ struct sysfs_dirent; 


#ifdef CONFIG_SYSFS



struct sysfs_dirent *kernfs_create_dir_ns(struct sysfs_dirent *parent,

					  const char *name, void *priv,

					  const void *ns);

struct sysfs_dirent *kernfs_create_link(struct sysfs_dirent *parent,

					const char *name,

					struct sysfs_dirent *target);
@@ -25,10 +28,16 @@ int kernfs_remove_by_name_ns(struct sysfs_dirent *parent, const char *name, 
			     const void *ns);

int kernfs_rename_ns(struct sysfs_dirent *sd, struct sysfs_dirent *new_parent,

		     const char *new_name, const void *new_ns);

void kernfs_enable_ns(struct sysfs_dirent *sd);

int kernfs_setattr(struct sysfs_dirent *sd, const struct iattr *iattr);



#else	/* CONFIG_SYSFS */



static inline struct sysfs_dirent *

kernfs_create_dir_ns(struct sysfs_dirent *parent, const char *name, void *priv,

		     const void *ns)

{ return ERR_PTR(-ENOSYS); }



static inline struct sysfs_dirent *

kernfs_create_link(struct sysfs_dirent *parent, const char *name,

		   struct sysfs_dirent *target)
@@ -45,12 +54,20 @@ static inline int kernfs_rename_ns(struct sysfs_dirent *sd, 
				   const char *new_name, const void *new_ns)

{ return -ENOSYS; }



static inline void kernfs_enable_ns(struct sysfs_dirent *sd) { }



static inline int kernfs_setattr(struct sysfs_dirent *sd,

				 const struct iattr *iattr)

{ return -ENOSYS; }



#endif	/* CONFIG_SYSFS */



static inline struct sysfs_dirent *

kernfs_create_dir(struct sysfs_dirent *parent, const char *name, void *priv)

{

	return kernfs_create_dir_ns(parent, name, priv, NULL);

}



static inline int kernfs_remove_by_name(struct sysfs_dirent *parent,

					const char *name)

{

include/linux/sysfs.h

+0 −6
Original line number Diff line number Diff line
@@ -219,8 +219,6 @@ int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target, 
void sysfs_delete_link(struct kobject *dir, struct kobject *targ,

			const char *name);



void sysfs_enable_ns(struct sysfs_dirent *sd);



int __must_check sysfs_create_group(struct kobject *kobj,

				    const struct attribute_group *grp);

int __must_check sysfs_create_groups(struct kobject *kobj,
@@ -354,10 +352,6 @@ static inline void sysfs_delete_link(struct kobject *k, struct kobject *t, 
{

}



static inline void sysfs_enable_ns(struct sysfs_dirent *sd)

{

}



static inline int sysfs_create_group(struct kobject *kobj,

				     const struct attribute_group *grp)

{

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