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Commit 2072f1af authored by Tejun Heo's avatar Tejun Heo Committed by Greg Kroah-Hartman
Browse files

sysfs, kernfs: move symlink core code to fs/kernfs/symlink.c 



Move core symlink code to fs/kernfs/symlink.c.  fs/sysfs/symlink.c now
only contains sysfs wrappers around kernfs interfaces.  The respective
declarations in fs/sysfs/sysfs.h are moved to
fs/kernfs/kernfs-internal.h.

This is pure relocation.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 414985ae

fs/kernfs/kernfs-internal.h

+5 −0
Original line number Diff line number Diff line
@@ -149,4 +149,9 @@ extern const struct file_operations kernfs_file_operations; 


void sysfs_unmap_bin_file(struct sysfs_dirent *sd);



/*

 * symlink.c

 */

extern const struct inode_operations sysfs_symlink_inode_operations;



#endif	/* __KERNFS_INTERNAL_H */

fs/kernfs/symlink.c

+139 −0
Original line number Diff line number Diff line
@@ -7,3 +7,142 @@ 
 *

 * This file is released under the GPLv2.

 */



#include <linux/fs.h>

#include <linux/gfp.h>

#include <linux/namei.h>



#include "kernfs-internal.h"



/**

 * kernfs_create_link - create a symlink

 * @parent: directory to create the symlink in

 * @name: name of the symlink

 * @target: target node for the symlink to point to

 *

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

 */

struct sysfs_dirent *kernfs_create_link(struct sysfs_dirent *parent,

					const char *name,

					struct sysfs_dirent *target)

{

	struct sysfs_dirent *sd;

	struct sysfs_addrm_cxt acxt;

	int error;



	sd = sysfs_new_dirent(name, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK);

	if (!sd)

		return ERR_PTR(-ENOMEM);



	if (parent->s_flags & SYSFS_FLAG_NS)

		sd->s_ns = target->s_ns;

	sd->s_symlink.target_sd = target;

	kernfs_get(target);	/* ref owned by symlink */



	sysfs_addrm_start(&acxt);

	error = sysfs_add_one(&acxt, sd, parent);

	sysfs_addrm_finish(&acxt);



	if (!error)

		return sd;



	kernfs_put(sd);

	return ERR_PTR(error);

}



static int sysfs_get_target_path(struct sysfs_dirent *parent_sd,

				 struct sysfs_dirent *target_sd, char *path)

{

	struct sysfs_dirent *base, *sd;

	char *s = path;

	int len = 0;



	/* go up to the root, stop at the base */

	base = parent_sd;

	while (base->s_parent) {

		sd = target_sd->s_parent;

		while (sd->s_parent && base != sd)

			sd = sd->s_parent;



		if (base == sd)

			break;



		strcpy(s, "../");

		s += 3;

		base = base->s_parent;

	}



	/* determine end of target string for reverse fillup */

	sd = target_sd;

	while (sd->s_parent && sd != base) {

		len += strlen(sd->s_name) + 1;

		sd = sd->s_parent;

	}



	/* check limits */

	if (len < 2)

		return -EINVAL;

	len--;

	if ((s - path) + len > PATH_MAX)

		return -ENAMETOOLONG;



	/* reverse fillup of target string from target to base */

	sd = target_sd;

	while (sd->s_parent && sd != base) {

		int slen = strlen(sd->s_name);



		len -= slen;

		strncpy(s + len, sd->s_name, slen);

		if (len)

			s[--len] = '/';



		sd = sd->s_parent;

	}



	return 0;

}



static int sysfs_getlink(struct dentry *dentry, char *path)

{

	struct sysfs_dirent *sd = dentry->d_fsdata;

	struct sysfs_dirent *parent_sd = sd->s_parent;

	struct sysfs_dirent *target_sd = sd->s_symlink.target_sd;

	int error;



	mutex_lock(&sysfs_mutex);

	error = sysfs_get_target_path(parent_sd, target_sd, path);

	mutex_unlock(&sysfs_mutex);



	return error;

}



static void *sysfs_follow_link(struct dentry *dentry, struct nameidata *nd)

{

	int error = -ENOMEM;

	unsigned long page = get_zeroed_page(GFP_KERNEL);

	if (page) {

		error = sysfs_getlink(dentry, (char *) page);

		if (error < 0)

			free_page((unsigned long)page);

	}

	nd_set_link(nd, error ? ERR_PTR(error) : (char *)page);

	return NULL;

}



static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd,

			   void *cookie)

{

	char *page = nd_get_link(nd);

	if (!IS_ERR(page))

		free_page((unsigned long)page);

}



const struct inode_operations sysfs_symlink_inode_operations = {

	.setxattr	= sysfs_setxattr,

	.readlink	= generic_readlink,

	.follow_link	= sysfs_follow_link,

	.put_link	= sysfs_put_link,

	.setattr	= sysfs_setattr,

	.getattr	= sysfs_getattr,

	.permission	= sysfs_permission,

};

fs/sysfs/symlink.c

+0 −137
Original line number Diff line number Diff line
@@ -11,53 +11,13 @@ 
 */



#include <linux/fs.h>

#include <linux/gfp.h>

#include <linux/mount.h>

#include <linux/module.h>

#include <linux/kobject.h>

#include <linux/namei.h>

#include <linux/mutex.h>

#include <linux/security.h>



#include "sysfs.h"



/**

 * kernfs_create_link - create a symlink

 * @parent: directory to create the symlink in

 * @name: name of the symlink

 * @target: target node for the symlink to point to

 *

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

 */

struct sysfs_dirent *kernfs_create_link(struct sysfs_dirent *parent,

					const char *name,

					struct sysfs_dirent *target)

{

	struct sysfs_dirent *sd;

	struct sysfs_addrm_cxt acxt;

	int error;



	sd = sysfs_new_dirent(name, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK);

	if (!sd)

		return ERR_PTR(-ENOMEM);



	if (parent->s_flags & SYSFS_FLAG_NS)

		sd->s_ns = target->s_ns;

	sd->s_symlink.target_sd = target;

	kernfs_get(target);	/* ref owned by symlink */



	sysfs_addrm_start(&acxt);

	error = sysfs_add_one(&acxt, sd, parent);

	sysfs_addrm_finish(&acxt);



	if (!error)

		return sd;



	kernfs_put(sd);

	return ERR_PTR(error);

}





static int sysfs_do_create_link_sd(struct sysfs_dirent *parent_sd,

				   struct kobject *target,

				   const char *name, int warn)
@@ -235,100 +195,3 @@ int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *targ, 
	return result;

}

EXPORT_SYMBOL_GPL(sysfs_rename_link_ns);
 


static int sysfs_get_target_path(struct sysfs_dirent *parent_sd,

				 struct sysfs_dirent *target_sd, char *path)

{

	struct sysfs_dirent *base, *sd;

	char *s = path;

	int len = 0;



	/* go up to the root, stop at the base */

	base = parent_sd;

	while (base->s_parent) {

		sd = target_sd->s_parent;

		while (sd->s_parent && base != sd)

			sd = sd->s_parent;



		if (base == sd)

			break;



		strcpy(s, "../");

		s += 3;

		base = base->s_parent;

	}



	/* determine end of target string for reverse fillup */

	sd = target_sd;

	while (sd->s_parent && sd != base) {

		len += strlen(sd->s_name) + 1;

		sd = sd->s_parent;

	}



	/* check limits */

	if (len < 2)

		return -EINVAL;

	len--;

	if ((s - path) + len > PATH_MAX)

		return -ENAMETOOLONG;



	/* reverse fillup of target string from target to base */

	sd = target_sd;

	while (sd->s_parent && sd != base) {

		int slen = strlen(sd->s_name);



		len -= slen;

		strncpy(s + len, sd->s_name, slen);

		if (len)

			s[--len] = '/';



		sd = sd->s_parent;

	}



	return 0;

}



static int sysfs_getlink(struct dentry *dentry, char *path)

{

	struct sysfs_dirent *sd = dentry->d_fsdata;

	struct sysfs_dirent *parent_sd = sd->s_parent;

	struct sysfs_dirent *target_sd = sd->s_symlink.target_sd;

	int error;



	mutex_lock(&sysfs_mutex);

	error = sysfs_get_target_path(parent_sd, target_sd, path);

	mutex_unlock(&sysfs_mutex);



	return error;

}



static void *sysfs_follow_link(struct dentry *dentry, struct nameidata *nd)

{

	int error = -ENOMEM;

	unsigned long page = get_zeroed_page(GFP_KERNEL);

	if (page) {

		error = sysfs_getlink(dentry, (char *) page);

		if (error < 0)

			free_page((unsigned long)page);

	}

	nd_set_link(nd, error ? ERR_PTR(error) : (char *)page);

	return NULL;

}



static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd,

			   void *cookie)

{

	char *page = nd_get_link(nd);

	if (!IS_ERR(page))

		free_page((unsigned long)page);

}



const struct inode_operations sysfs_symlink_inode_operations = {

	.setxattr	= sysfs_setxattr,

	.readlink	= generic_readlink,

	.follow_link	= sysfs_follow_link,

	.put_link	= sysfs_put_link,

	.setattr	= sysfs_setattr,

	.getattr	= sysfs_getattr,

	.permission	= sysfs_permission,

};

fs/sysfs/sysfs.h

+0 −1
Original line number Diff line number Diff line
@@ -50,7 +50,6 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd, 
/*

 * symlink.c

 */

extern const struct inode_operations sysfs_symlink_inode_operations;

int sysfs_create_link_sd(struct sysfs_dirent *sd, struct kobject *target,

			 const char *name);