OpenWrt – Rev 1
?pathlinks?
From: Felix Fietkau <nbd@nbd.name>
Date: Fri, 10 Apr 2015 13:35:29 +0200
Subject: [PATCH] jffs2: use .rename2 and add RENAME_WHITEOUT support
It is required for renames on overlayfs
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
--- a/fs/jffs2/dir.c
+++ b/fs/jffs2/dir.c
@@ -35,7 +35,7 @@ static int jffs2_mkdir (struct inode *,s
static int jffs2_rmdir (struct inode *,struct dentry *);
static int jffs2_mknod (struct inode *,struct dentry *,umode_t,dev_t);
static int jffs2_rename (struct inode *, struct dentry *,
- struct inode *, struct dentry *);
+ struct inode *, struct dentry *, unsigned int);
const struct file_operations jffs2_dir_operations =
{
@@ -57,7 +57,7 @@ const struct inode_operations jffs2_dir_
.mkdir = jffs2_mkdir,
.rmdir = jffs2_rmdir,
.mknod = jffs2_mknod,
- .rename = jffs2_rename,
+ .rename2 = jffs2_rename,
.get_acl = jffs2_get_acl,
.set_acl = jffs2_set_acl,
.setattr = jffs2_setattr,
@@ -752,8 +752,27 @@ static int jffs2_mknod (struct inode *di
return ret;
}
+static int jffs2_whiteout(struct inode *old_dir, struct dentry *old_dentry)
+{
+ struct dentry *wh;
+ int err;
+
+ wh = d_alloc(old_dentry->d_parent, &old_dentry->d_name);
+ if (!wh)
+ return -ENOMEM;
+
+ err = jffs2_mknod(old_dir, wh, S_IFCHR | WHITEOUT_MODE,
+ WHITEOUT_DEV);
+ if (err)
+ return err;
+
+ d_rehash(wh);
+ return 0;
+}
+
static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry,
- struct inode *new_dir_i, struct dentry *new_dentry)
+ struct inode *new_dir_i, struct dentry *new_dentry,
+ unsigned int flags)
{
int ret;
struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dir_i->i_sb);
@@ -761,6 +780,9 @@ static int jffs2_rename (struct inode *o
uint8_t type;
uint32_t now;
+ if (flags & ~RENAME_WHITEOUT)
+ return -EINVAL;
+
/* The VFS will check for us and prevent trying to rename a
* file over a directory and vice versa, but if it's a directory,
* the VFS can't check whether the victim is empty. The filesystem
@@ -824,9 +846,14 @@ static int jffs2_rename (struct inode *o
if (S_ISDIR(old_dentry->d_inode->i_mode) && !victim_f)
inc_nlink(new_dir_i);
- /* Unlink the original */
- ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
- old_dentry->d_name.name, old_dentry->d_name.len, NULL, now);
+ if (flags & RENAME_WHITEOUT)
+ /* Replace with whiteout */
+ ret = jffs2_whiteout(old_dir_i, old_dentry);
+ else
+ /* Unlink the original */
+ ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
+ old_dentry->d_name.name,
+ old_dentry->d_name.len, NULL, now);
/* We don't touch inode->i_nlink */