ovl: create ovl_need_index() helper (24b33ee1) · Commits · 戴 / test

fs/overlayfs/copy_up.c

+1 −5

Original line number	Diff line number	Diff line
		@@ -536,11 +536,7 @@ static int ovl_do_copy_up(struct ovl_copy_up_ctx *c)
		{
		int err;
		struct ovl_fs *ofs = c->dentry->d_sb->s_fs_info;
		bool indexed = false;

		if (ovl_indexdir(c->dentry->d_sb) && !S_ISDIR(c->stat.mode) &&
		c->stat.nlink > 1)
		indexed = true;
		bool indexed = ovl_need_index(c->dentry);

		if (S_ISDIR(c->stat.mode) \|\| c->stat.nlink == 1 \|\| indexed)
		c->origin = true;

fs/overlayfs/overlayfs.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -241,6 +241,7 @@ void ovl_clear_flag(unsigned long flag, struct inode *inode);
		bool ovl_test_flag(unsigned long flag, struct inode *inode);
		bool ovl_inuse_trylock(struct dentry *dentry);
		void ovl_inuse_unlock(struct dentry *dentry);
		bool ovl_need_index(struct dentry *dentry);
		int ovl_nlink_start(struct dentry dentry, bool locked);
		void ovl_nlink_end(struct dentry *dentry, bool locked);
		int ovl_lock_rename_workdir(struct dentry workdir, struct dentry upperdir);

fs/overlayfs/util.c

+20 −4

Original line number	Diff line number	Diff line
		@@ -463,6 +463,23 @@ void ovl_inuse_unlock(struct dentry *dentry)
		}
		}

		/*
		* Does this overlay dentry need to be indexed on copy up?
		*/
		bool ovl_need_index(struct dentry *dentry)
		{
		struct dentry *lower = ovl_dentry_lower(dentry);

		if (!lower \|\| !ovl_indexdir(dentry->d_sb))
		return false;

		/* Index only lower hardlinks on copy up */
		if (!d_is_dir(lower) && d_inode(lower)->i_nlink > 1)
		return true;

		return false;
		}

		/* Caller must hold OVL_I(inode)->lock */
		static void ovl_cleanup_index(struct dentry *dentry)
		{
		@@ -533,11 +550,11 @@ int ovl_nlink_start(struct dentry dentry, bool locked)

		/*
		* With inodes index is enabled, we store the union overlay nlink
		* in an xattr on the index inode. When whiting out lower hardlinks
		* in an xattr on the index inode. When whiting out an indexed lower,
		* we need to decrement the overlay persistent nlink, but before the
		* first copy up, we have no upper index inode to store the xattr.
		*
		* As a workaround, before whiteout/rename over of a lower hardlink,
		* As a workaround, before whiteout/rename over an indexed lower,
		* copy up to create the upper index. Creating the upper index will
		* initialize the overlay nlink, so it could be dropped if unlink
		* or rename succeeds.
		@@ -545,8 +562,7 @@ int ovl_nlink_start(struct dentry dentry, bool locked)
		* TODO: implement metadata only index copy up when called with
		* ovl_copy_up_flags(dentry, O_PATH).
		*/
		if (ovl_indexdir(dentry->d_sb) && !ovl_dentry_has_upper_alias(dentry) &&
		d_inode(ovl_dentry_lower(dentry))->i_nlink > 1) {
		if (ovl_need_index(dentry) && !ovl_dentry_has_upper_alias(dentry)) {
		err = ovl_copy_up(dentry);
		if (err)
		return err;

Admin message