procfs: new helper - PDE_DATA(inode)

The only part of proc_dir_entry the code outside of fs/proc
really cares about is PDE(inode)->data.  Provide a helper
for that; static inline for now, eventually will be moved
to fs/proc, along with the knowledge of struct proc_dir_entry
layout.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/drivers/ide/ide-disk_proc.c b/drivers/ide/ide-disk_proc.c
index 8b570a1..0d1fae6 100644
--- a/drivers/ide/ide-disk_proc.c
+++ b/drivers/ide/ide-disk_proc.c
@@ -53,7 +53,7 @@
 
 static int idedisk_cache_proc_open(struct inode *inode, struct file *file)
 {
-	return single_open(file, idedisk_cache_proc_show, PDE(inode)->data);
+	return single_open(file, idedisk_cache_proc_show, PDE_DATA(inode));
 }
 
 static const struct file_operations idedisk_cache_proc_fops = {
@@ -74,7 +74,7 @@
 
 static int idedisk_capacity_proc_open(struct inode *inode, struct file *file)
 {
-	return single_open(file, idedisk_capacity_proc_show, PDE(inode)->data);
+	return single_open(file, idedisk_capacity_proc_show, PDE_DATA(inode));
 }
 
 static const struct file_operations idedisk_capacity_proc_fops = {
@@ -115,7 +115,7 @@
 
 static int idedisk_sv_proc_open(struct inode *inode, struct file *file)
 {
-	return single_open(file, idedisk_sv_proc_show, PDE(inode)->data);
+	return single_open(file, idedisk_sv_proc_show, PDE_DATA(inode));
 }
 
 static const struct file_operations idedisk_sv_proc_fops = {
@@ -133,7 +133,7 @@
 
 static int idedisk_st_proc_open(struct inode *inode, struct file *file)
 {
-	return single_open(file, idedisk_st_proc_show, PDE(inode)->data);
+	return single_open(file, idedisk_st_proc_show, PDE_DATA(inode));
 }
 
 static const struct file_operations idedisk_st_proc_fops = {