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, @@ -756,8 +756,27 @@ 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); @@ -765,6 +784,9 @@ 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 @@ -828,9 +850,14 @@ 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 */