sysfs: make kobj point to sysfs_dirent instead of dentry

As kobj sysfs dentries and inodes are gonna be made reclaimable,
dentry can't be used as naming token for sysfs file/directory, replace
kobj->dentry with kobj->sd.  The only external interface change is
shadow directory handling.  All other changes are contained in kobj
and sysfs.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 59 insertions, 60 deletions

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 4762a9aa0b27..31b6cf30636d 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -368,9 +368,10 @@ struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
         return sd;
 }
 
-static int create_dir(struct kobject *kobj, struct dentry *parent,
-                      const char *name, struct dentry **p_dentry)
+static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,
+                      const char *name, struct sysfs_dirent **p_sd)
 {
+        struct dentry *parent = parent_sd->s_dentry;
         int error;
         umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO;
         struct dentry *dentry;
@@ -409,14 +410,14 @@ static int create_dir(struct kobject *kobj, struct dentry *parent,
 
         /* link in */
         error = -EEXIST;
-        if (sysfs_find_dirent(parent->d_fsdata, name))
+        if (sysfs_find_dirent(parent_sd, name))
                 goto out_iput;
 
         sysfs_instantiate(dentry, inode);
         inc_nlink(parent->d_inode);
-        sysfs_attach_dirent(sd, parent->d_fsdata, dentry);
+        sysfs_attach_dirent(sd, parent_sd, dentry);
 
-        *p_dentry = dentry;
+        *p_sd = sd;
         error = 0;
         goto out_unlock;        /* pin directory dentry in core */
 
@@ -433,38 +434,37 @@ static int create_dir(struct kobject *kobj, struct dentry *parent,
         return error;
 }
 
-
-int sysfs_create_subdir(struct kobject * k, const char * n, struct dentry ** d)
+int sysfs_create_subdir(struct kobject *kobj, const char *name,
+                        struct sysfs_dirent **p_sd)
 {
-        return create_dir(k,k->dentry,n,d);
+        return create_dir(kobj, kobj->sd, name, p_sd);
 }
 
 /**
  *      sysfs_create_dir - create a directory for an object.
  *      @kobj:          object we're creating directory for. 
- *      @shadow_parent: parent parent object.
+ *      @shadow_parent: parent object.
  */
-
-int sysfs_create_dir(struct kobject * kobj, struct dentry *shadow_parent)
+int sysfs_create_dir(struct kobject *kobj,
+                     struct sysfs_dirent *shadow_parent_sd)
 {
-        struct dentry * dentry = NULL;
-        struct dentry * parent;
+        struct sysfs_dirent *parent_sd, *sd;
         int error = 0;
 
         BUG_ON(!kobj);
 
-        if (shadow_parent)
-                parent = shadow_parent;
+        if (shadow_parent_sd)
+                parent_sd = shadow_parent_sd;
         else if (kobj->parent)
-                parent = kobj->parent->dentry;
+                parent_sd = kobj->parent->sd;
         else if (sysfs_mount && sysfs_mount->mnt_sb)
-                parent = sysfs_mount->mnt_sb->s_root;
+                parent_sd = sysfs_mount->mnt_sb->s_root->d_fsdata;
         else
                 return -EFAULT;
 
-        error = create_dir(kobj,parent,kobject_name(kobj),&dentry);
+        error = create_dir(kobj, parent_sd, kobject_name(kobj), &sd);
         if (!error)
-                kobj->dentry = dentry;
+                kobj->sd = sd;
         return error;
 }
 
@@ -525,18 +525,16 @@ const struct inode_operations sysfs_dir_inode_operations = {
         .setattr        = sysfs_setattr,
 };
 
-static void remove_dir(struct dentry * d)
+static void remove_dir(struct sysfs_dirent *sd)
 {
-        struct dentry *parent = d->d_parent;
-        struct sysfs_dirent *sd = d->d_fsdata;
+        struct dentry *parent = sd->s_parent->s_dentry;
 
         mutex_lock(&parent->d_inode->i_mutex);
 
         sysfs_unlink_sibling(sd);
         sd->s_flags |= SYSFS_FLAG_REMOVED;
 
-        pr_debug(" o %s removing done (%d)\n",d->d_name.name,
-                 atomic_read(&d->d_count));
+        pr_debug(" o %s removing done\n", sd->s_name);
 
         mutex_unlock(&parent->d_inode->i_mutex);
 
@@ -545,25 +543,26 @@ static void remove_dir(struct dentry * d)
         sysfs_put(sd);
 }
 
-void sysfs_remove_subdir(struct dentry * d)
+void sysfs_remove_subdir(struct sysfs_dirent *sd)
 {
-        remove_dir(d);
+        remove_dir(sd);
 }
 
 
-static void __sysfs_remove_dir(struct dentry *dentry)
+static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd)
 {
         struct sysfs_dirent *removed = NULL;
-        struct sysfs_dirent *parent_sd;
         struct sysfs_dirent **pos;
+        struct dentry *dir;
 
-        if (!dentry)
+        if (!dir_sd)
                 return;
 
-        pr_debug("sysfs %s: removing dir\n",dentry->d_name.name);
-        mutex_lock(&dentry->d_inode->i_mutex);
-        parent_sd = dentry->d_fsdata;
-        pos = &parent_sd->s_children;
+        dir = dir_sd->s_dentry;
+
+        pr_debug("sysfs %s: removing dir\n", dir_sd->s_name);
+        mutex_lock(&dir->d_inode->i_mutex);
+        pos = &dir_sd->s_children;
         while (*pos) {
                 struct sysfs_dirent *sd = *pos;
 
@@ -575,7 +574,7 @@ static void __sysfs_remove_dir(struct dentry *dentry)
                 } else
                         pos = &(*pos)->s_sibling;
         }
-        mutex_unlock(&dentry->d_inode->i_mutex);
+        mutex_unlock(&dir->d_inode->i_mutex);
 
         while (removed) {
                 struct sysfs_dirent *sd = removed;
@@ -588,7 +587,7 @@ static void __sysfs_remove_dir(struct dentry *dentry)
                 sysfs_put(sd);
         }
 
-        remove_dir(dentry);
+        remove_dir(dir_sd);
 }
 
 /**
@@ -602,25 +601,25 @@ static void __sysfs_remove_dir(struct dentry *dentry)
 
 void sysfs_remove_dir(struct kobject * kobj)
 {
-        struct dentry *d = kobj->dentry;
+        struct sysfs_dirent *sd = kobj->sd;
 
         spin_lock(&kobj_sysfs_assoc_lock);
-        kobj->dentry = NULL;
+        kobj->sd = NULL;
         spin_unlock(&kobj_sysfs_assoc_lock);
 
-        __sysfs_remove_dir(d);
+        __sysfs_remove_dir(sd);
 }
 
-int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent,
+int sysfs_rename_dir(struct kobject *kobj, struct sysfs_dirent *new_parent_sd,
                      const char *new_name)
 {
-        struct sysfs_dirent *sd = kobj->dentry->d_fsdata;
-        struct sysfs_dirent *parent_sd = new_parent->d_fsdata;
+        struct sysfs_dirent *sd = kobj->sd;
+        struct dentry *new_parent = new_parent_sd->s_dentry;
         struct dentry *new_dentry;
         char *dup_name;
         int error;
 
-        if (!new_parent)
+        if (!new_parent_sd)
                 return -EFAULT;
 
         down_write(&sysfs_rename_sem);
@@ -637,9 +636,9 @@ int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent,
          * shadows of the same directory
          */
         error = -EINVAL;
-        if (kobj->dentry->d_parent->d_inode != new_parent->d_inode ||
+        if (sd->s_parent->s_dentry->d_inode != new_parent->d_inode ||
             new_dentry->d_parent->d_inode != new_parent->d_inode ||
-            new_dentry == kobj->dentry)
+            new_dentry == sd->s_dentry)
                 goto out_dput;
 
         error = -EEXIST;
@@ -661,12 +660,12 @@ int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent,
 
         /* move under the new parent */
         d_add(new_dentry, NULL);
-        d_move(kobj->dentry, new_dentry);
+        d_move(sd->s_dentry, new_dentry);
 
         sysfs_unlink_sibling(sd);
-        sysfs_get(parent_sd);
+        sysfs_get(new_parent_sd);
         sysfs_put(sd->s_parent);
-        sd->s_parent = parent_sd;
+        sd->s_parent = new_parent_sd;
         sysfs_link_sibling(sd);
 
         error = 0;
@@ -691,9 +690,9 @@ int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent)
         int error;
 
         old_parent_dentry = kobj->parent ?
-                kobj->parent->dentry : sysfs_mount->mnt_sb->s_root;
+                kobj->parent->sd->s_dentry : sysfs_mount->mnt_sb->s_root;
         new_parent_dentry = new_parent ?
-                new_parent->dentry : sysfs_mount->mnt_sb->s_root;
+                new_parent->sd->s_dentry : sysfs_mount->mnt_sb->s_root;
 
         if (old_parent_dentry->d_inode == new_parent_dentry->d_inode)
                 return 0;       /* nothing to move */
@@ -705,7 +704,7 @@ again:
         }
 
         new_parent_sd = new_parent_dentry->d_fsdata;
-        sd = kobj->dentry->d_fsdata;
+        sd = kobj->sd;
 
         new_dentry = lookup_one_len(kobj->name, new_parent_dentry,
                                     strlen(kobj->name));
@@ -715,7 +714,7 @@ again:
         } else
                 error = 0;
         d_add(new_dentry, NULL);
-        d_move(kobj->dentry, new_dentry);
+        d_move(sd->s_dentry, new_dentry);
         dput(new_dentry);
 
         /* Remove from old parent's list and insert into new parent's list. */
@@ -885,7 +884,7 @@ int sysfs_make_shadowed_dir(struct kobject *kobj,
         struct inode *inode;
         struct inode_operations *i_op;
 
-        inode = kobj->dentry->d_inode;
+        inode = kobj->sd->s_dentry->d_inode;
         if (inode->i_op != &sysfs_dir_inode_operations)
                 return -EINVAL;
 
@@ -912,16 +911,16 @@ int sysfs_make_shadowed_dir(struct kobject *kobj,
  *      directory.
  */
 
-struct dentry *sysfs_create_shadow_dir(struct kobject *kobj)
+struct sysfs_dirent *sysfs_create_shadow_dir(struct kobject *kobj)
 {
-        struct dentry *dir = kobj->dentry;
+        struct dentry *dir = kobj->sd->s_dentry;
         struct inode *inode = dir->d_inode;
         struct dentry *parent = dir->d_parent;
         struct sysfs_dirent *parent_sd = parent->d_fsdata;
         struct dentry *shadow;
         struct sysfs_dirent *sd;
 
-        shadow = ERR_PTR(-EINVAL);
+        sd = ERR_PTR(-EINVAL);
         if (!sysfs_is_shadowed_inode(inode))
                 goto out;
 
@@ -944,25 +943,25 @@ struct dentry *sysfs_create_shadow_dir(struct kobject *kobj)
         dget(shadow);           /* Extra count - pin the dentry in core */
 
 out:
-        return shadow;
+        return sd;
 nomem:
         dput(shadow);
-        shadow = ERR_PTR(-ENOMEM);
+        sd = ERR_PTR(-ENOMEM);
         goto out;
 }
 
 /**
  *      sysfs_remove_shadow_dir - remove an object's directory.
- *      @shadow: dentry of shadow directory
+ *      @shadow_sd: sysfs_dirent of shadow directory
  *
  *      The only thing special about this is that we remove any files in
  *      the directory before we remove the directory, and we've inlined
  *      what used to be sysfs_rmdir() below, instead of calling separately.
  */
 
-void sysfs_remove_shadow_dir(struct dentry *shadow)
+void sysfs_remove_shadow_dir(struct sysfs_dirent *shadow_sd)
 {
-        __sysfs_remove_dir(shadow);
+        __sysfs_remove_dir(shadow_sd);
 }
 
 const struct file_operations sysfs_dir_operations = {