sysfs: kill attribute file orphaning

Now that sysfs_dirent can be disconnected from kobject on deletion,
there is no need to orphan each attribute files.  All [bin_]attribute
nodes are automatically orphaned when the parent node is deleted.
Kill attribute file orphaning.

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

1 files changed, 13 insertions, 52 deletions

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 310430baf572..d673d9b5d33f 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -50,29 +50,15 @@ static struct sysfs_ops subsys_sysfs_ops = {
         .store  = subsys_attr_store,
 };
 
-/**
- *      add_to_collection - add buffer to a collection
- *      @buffer:        buffer to be added
- *      @node:          inode of set to add to
- */
-
-static inline void
-add_to_collection(struct sysfs_buffer *buffer, struct inode *node)
-{
-        struct sysfs_buffer_collection *set = node->i_private;
-
-        mutex_lock(&node->i_mutex);
-        list_add(&buffer->associates, &set->associates);
-        mutex_unlock(&node->i_mutex);
-}
-
-static inline void
-remove_from_collection(struct sysfs_buffer *buffer, struct inode *node)
-{
-        mutex_lock(&node->i_mutex);
-        list_del(&buffer->associates);
-        mutex_unlock(&node->i_mutex);
-}
+struct sysfs_buffer {
+        size_t                  count;
+        loff_t                  pos;
+        char                    * page;
+        struct sysfs_ops        * ops;
+        struct semaphore        sem;
+        int                     needs_read_fill;
+        int                     event;
+};
 
 /**
  *      fill_read_buffer - allocate and fill buffer from object.
@@ -144,10 +130,7 @@ sysfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 
         down(&buffer->sem);
         if (buffer->needs_read_fill) {
-                if (buffer->orphaned)
-                        retval = -ENODEV;
-                else
-                        retval = fill_read_buffer(file->f_path.dentry,buffer);
+                retval = fill_read_buffer(file->f_path.dentry,buffer);
                 if (retval)
                         goto out;
         }
@@ -246,16 +229,11 @@ sysfs_write_file(struct file *file, const char __user *buf, size_t count, loff_t
         ssize_t len;
 
         down(&buffer->sem);
-        if (buffer->orphaned) {
-                len = -ENODEV;
-                goto out;
-        }
         len = fill_write_buffer(buffer, buf, count);
         if (len > 0)
                 len = flush_write_buffer(file->f_path.dentry, buffer, len);
         if (len > 0)
                 *ppos += len;
-out:
         up(&buffer->sem);
         return len;
 }
@@ -265,7 +243,6 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
         struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
         struct attribute *attr = attr_sd->s_elem.attr.attr;
         struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
-        struct sysfs_buffer_collection *set;
         struct sysfs_buffer * buffer;
         struct sysfs_ops * ops = NULL;
         int error;
@@ -289,26 +266,14 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
         else
                 ops = &subsys_sysfs_ops;
 
+        error = -EACCES;
+
         /* No sysfs operations, either from having no subsystem,
          * or the subsystem have no operations.
          */
-        error = -EACCES;
         if (!ops)
                 goto err_mput;
 
-        /* make sure we have a collection to add our buffers to */
-        mutex_lock(&inode->i_mutex);
-        if (!(set = inode->i_private)) {
-                error = -ENOMEM;
-                if (!(set = inode->i_private = kmalloc(sizeof(struct sysfs_buffer_collection), GFP_KERNEL)))
-                        goto err_mput;
-                else
-                        INIT_LIST_HEAD(&set->associates);
-        }
-        mutex_unlock(&inode->i_mutex);
-
-        error = -EACCES;
-
         /* File needs write support.
          * The inode's perms must say it's ok, 
          * and we must have a store method.
@@ -335,11 +300,9 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
         if (!buffer)
                 goto err_mput;
 
-        INIT_LIST_HEAD(&buffer->associates);
         init_MUTEX(&buffer->sem);
         buffer->needs_read_fill = 1;
         buffer->ops = ops;
-        add_to_collection(buffer, inode);
         file->private_data = buffer;
 
         /* open succeeded, put active references and pin attr_sd */
@@ -358,10 +321,8 @@ static int sysfs_release(struct inode * inode, struct file * filp)
 {
         struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
         struct attribute *attr = attr_sd->s_elem.attr.attr;
-        struct sysfs_buffer * buffer = filp->private_data;
+        struct sysfs_buffer *buffer = filp->private_data;
 
-        if (buffer)
-                remove_from_collection(buffer, inode);
         sysfs_put(attr_sd);
         /* After this point, attr should not be accessed. */
         module_put(attr->owner);