fs: proc: store PDE()->data into inode->i_private

PDE_DATA(inode) is introduced to get user private data and hide the
layout of struct proc_dir_entry.  The inode->i_private is used to do the
same thing as well.  Save a copy of user private data to inode->
i_private when proc inode is allocated.  This means the user also can
get their private data by inode->i_private.

Introduce pde_data() to wrap inode->i_private so that we can remove
PDE_DATA() from fs/proc/generic.c and make PTE_DATE() as a wrapper of
pde_data().  It will be easier if we decide to remove PDE_DATE() in the
future.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Muchun Song <[email protected]>
Acked-by: Christian Brauner <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: Alexey Gladkov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 599eb724ff2d..f84355c5a36d 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -650,6 +650,7 @@ struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de)
 		return NULL;
 	}
 
+	inode->i_private = de->data;
 	inode->i_ino = de->low_ino;
 	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
 	PROC_I(inode)->pde = de;