treewide: fix replace nbd@openwrt.org with nbd@nbd.name
[openwrt.org/openwrt.git] / target / linux / generic / patches-4.4 / 110-jffs2-use-.rename2-and-add-RENAME_WHITEOUT-support.patch
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From: Felix Fietkau <nbd@openwrt.org>
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@openwrt.org>
---
 
--- 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,
@@ -754,8 +754,27 @@ 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);
@@ -763,6 +782,9 @@ 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
@@ -826,9 +848,14 @@ static int jffs2_rename (struct inode *o
        if (d_is_dir(old_dentry) && !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 */
 
 
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