configfs: Add permission and ownership to configfs objects.

configfs always made item and attribute ownership root.root and
permissions based on a umask of 022.  Add ->setattr() to allow
chown(2)/chmod(2), and persist the changes for the lifetime of the
items and attributes.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

1 files changed, 10 insertions, 9 deletions

diff --git a/fs/configfs/file.c b/fs/configfs/file.c
index c26cd61f13af..3921920d8716 100644
--- a/fs/configfs/file.c
+++ b/fs/configfs/file.c
@@ -26,7 +26,6 @@
 
 #include <linux/fs.h>
 #include <linux/module.h>
-#include <linux/dnotify.h>
 #include <linux/slab.h>
 #include <asm/uaccess.h>
 #include <asm/semaphore.h>
@@ -150,7 +149,7 @@ out:
 /**
  *      fill_write_buffer - copy buffer from userspace.
  *      @buffer:        data buffer for file.
- *      @userbuf:       data from user.
+ *      @buf:           data from user.
  *      @count:         number of bytes in @userbuf.
  *
  *      Allocate @buffer->page if it hasn't been already, then
@@ -177,8 +176,9 @@ fill_write_buffer(struct configfs_buffer * buffer, const char __user * buf, size
 
 /**
  *      flush_write_buffer - push buffer to config_item.
- *      @file:          file pointer.
+ *      @dentry:        dentry to the attribute
  *      @buffer:        data buffer for file.
+ *      @count:         number of bytes
  *
  *      Get the correct pointers for the config_item and the attribute we're
  *      dealing with, then call the store() method for the attribute,
@@ -217,15 +217,16 @@ static ssize_t
 configfs_write_file(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 {
         struct configfs_buffer * buffer = file->private_data;
+        ssize_t len;
 
         down(&buffer->sem);
-        count = fill_write_buffer(buffer,buf,count);
-        if (count > 0)
-                count = flush_write_buffer(file->f_dentry,buffer,count);
-        if (count > 0)
-                *ppos += count;
+        len = fill_write_buffer(buffer, buf, count);
+        if (len > 0)
+                len = flush_write_buffer(file->f_dentry, buffer, count);
+        if (len > 0)
+                *ppos += len;
         up(&buffer->sem);
-        return count;
+        return len;
 }
 
 static int check_perm(struct inode * inode, struct file * file)