sysfs: make directory dentries and inodes reclaimable

[powerpc.git] / fs / sysfs / file.c

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 69bacf1..cc49799 100644 (file)
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -362,43 +362,22 @@ static unsigned int sysfs_poll(struct file *filp, poll_table *wait)
        return POLLERR|POLLPRI;
 }
 
-
-static struct dentry *step_down(struct dentry *dir, const char * name)
+void sysfs_notify(struct kobject *k, char *dir, char *attr)
 {
-       struct dentry * de;
-
-       if (dir == NULL || dir->d_inode == NULL)
-               return NULL;
-
-       mutex_lock(&dir->d_inode->i_mutex);
-       de = lookup_one_len(name, dir, strlen(name));
-       mutex_unlock(&dir->d_inode->i_mutex);
-       dput(dir);
-       if (IS_ERR(de))
-               return NULL;
-       if (de->d_inode == NULL) {
-               dput(de);
-               return NULL;
-       }
-       return de;
-}
+       struct sysfs_dirent *sd = k->sd;
 
-void sysfs_notify(struct kobject * k, char *dir, char *attr)
-{
-       struct dentry *de = k->sd->s_dentry;
-       if (de)
-               dget(de);
-       if (de && dir)
-               de = step_down(de, dir);
-       if (de && attr)
-               de = step_down(de, attr);
-       if (de) {
-               struct sysfs_dirent * sd = de->d_fsdata;
-               if (sd)
-                       atomic_inc(&sd->s_event);
+       mutex_lock(&sysfs_mutex);
+
+       if (sd && dir)
+               sd = sysfs_find_dirent(sd, dir);
+       if (sd && attr)
+               sd = sysfs_find_dirent(sd, attr);
+       if (sd) {
+               atomic_inc(&sd->s_event);
                wake_up_interruptible(&k->poll);
-               dput(de);
        }
+
+       mutex_unlock(&sysfs_mutex);
 }
 EXPORT_SYMBOL_GPL(sysfs_notify);
 
@@ -485,30 +464,31 @@ EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
  */
 int sysfs_update_file(struct kobject * kobj, const struct attribute * attr)
 {
-       struct dentry *dir = kobj->sd->s_dentry;
-       struct dentry * victim;
-       int res = -ENOENT;
-
-       mutex_lock(&dir->d_inode->i_mutex);
-       victim = lookup_one_len(attr->name, dir, strlen(attr->name));
-       if (!IS_ERR(victim)) {
-               /* make sure dentry is really there */
-               if (victim->d_inode && 
-                   (victim->d_parent->d_inode == dir->d_inode)) {
-                       victim->d_inode->i_mtime = CURRENT_TIME;
-                       fsnotify_modify(victim);
-                       res = 0;
-               } else
-                       d_drop(victim);
-               
-               /**
-                * Drop the reference acquired from lookup_one_len() above.
-                */
-               dput(victim);
+       struct sysfs_dirent *victim_sd = NULL;
+       struct dentry *victim = NULL;
+       int rc;
+
+       rc = -ENOENT;
+       victim_sd = sysfs_get_dirent(kobj->sd, attr->name);
+       if (!victim_sd)
+               goto out;
+
+       victim = sysfs_get_dentry(victim_sd);
+       if (IS_ERR(victim)) {
+               rc = PTR_ERR(victim);
+               victim = NULL;
+               goto out;
        }
-       mutex_unlock(&dir->d_inode->i_mutex);
 
-       return res;
+       mutex_lock(&victim->d_inode->i_mutex);
+       victim->d_inode->i_mtime = CURRENT_TIME;
+       fsnotify_modify(victim);
+       mutex_unlock(&victim->d_inode->i_mutex);
+       rc = 0;
+ out:
+       dput(victim);
+       sysfs_put(victim_sd);
+       return rc;
 }
 
 
@@ -521,30 +501,34 @@ int sysfs_update_file(struct kobject * kobj, const struct attribute * attr)
  */
 int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
 {
-       struct dentry *dir = kobj->sd->s_dentry;
-       struct dentry *victim;
+       struct sysfs_dirent *victim_sd = NULL;
+       struct dentry *victim = NULL;
        struct inode * inode;
        struct iattr newattrs;
-       int res = -ENOENT;
-
-       mutex_lock(&dir->d_inode->i_mutex);
-       victim = lookup_one_len(attr->name, dir, strlen(attr->name));
-       if (!IS_ERR(victim)) {
-               if (victim->d_inode &&
-                   (victim->d_parent->d_inode == dir->d_inode)) {
-                       inode = victim->d_inode;
-                       mutex_lock(&inode->i_mutex);
-                       newattrs.ia_mode = (mode & S_IALLUGO) |
-                                               (inode->i_mode & ~S_IALLUGO);
-                       newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
-                       res = notify_change(victim, &newattrs);
-                       mutex_unlock(&inode->i_mutex);
-               }
-               dput(victim);
+       int rc;
+
+       rc = -ENOENT;
+       victim_sd = sysfs_get_dirent(kobj->sd, attr->name);
+       if (!victim_sd)
+               goto out;
+
+       victim = sysfs_get_dentry(victim_sd);
+       if (IS_ERR(victim)) {
+               rc = PTR_ERR(victim);
+               victim = NULL;
+               goto out;
        }
-       mutex_unlock(&dir->d_inode->i_mutex);
 
-       return res;
+       inode = victim->d_inode;
+       mutex_lock(&inode->i_mutex);
+       newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
+       newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
+       rc = notify_change(victim, &newattrs);
+       mutex_unlock(&inode->i_mutex);
+ out:
+       dput(victim);
+       sysfs_put(victim_sd);
+       return rc;
 }
 EXPORT_SYMBOL_GPL(sysfs_chmod_file);