[PATCH 22/34] sysfs, kernfs: move symlink core code to fs/kernfs/symlink.c

Tejun Heo
2013-11-28T19:59:17Z

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: Tejun Heo <tj@kernel.org>
---
fs/kernfs/kernfs-internal.h | 5 ++
fs/kernfs/symlink.c | 139 ++++++++++++++++++++++++++++++++++++++++++++
fs/sysfs/symlink.c | 137 -------------------------------------------
fs/sysfs/sysfs.h | 1 -
4 files changed, 144 insertions(+), 138 deletions(-)

diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index 38e3a16..62ae35f 100644
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -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 */
diff --git a/fs/kernfs/symlink.c b/fs/kernfs/symlink.c
index 2578715..af3570b 100644
--- a/fs/kernfs/symlink.c
+++ b/fs/kernfs/symlink.c
@@ -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,
+};
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index b137aa3..6797c9c 100644
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -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 @@ out:
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,
-};
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 4b8b60d..6d0dcea 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -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);

--
1.8.4.2