Commit cefd1b83 authored by Miklos Szeredi's avatar Miklos Szeredi
Browse files

fuse: decrement nlink on overwriting rename 



Rename didn't decrement/clear nlink on overwritten target inode.

Create a common helper fuse_entry_unlinked() that handles this for unlink,
rmdir and rename.

Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 84840efc

fs/fuse/dir.c

+27 −22
Original line number Diff line number Diff line
@@ -755,6 +755,29 @@ void fuse_update_ctime(struct inode *inode) 
	}

}



static void fuse_entry_unlinked(struct dentry *entry)

{

	struct inode *inode = d_inode(entry);

	struct fuse_conn *fc = get_fuse_conn(inode);

	struct fuse_inode *fi = get_fuse_inode(inode);



	spin_lock(&fi->lock);

	fi->attr_version = atomic64_inc_return(&fc->attr_version);

	/*

	 * If i_nlink == 0 then unlink doesn't make sense, yet this can

	 * happen if userspace filesystem is careless.  It would be

	 * difficult to enforce correct nlink usage so just ignore this

	 * condition here

	 */

	if (S_ISDIR(inode->i_mode))

		clear_nlink(inode);

	else if (inode->i_nlink > 0)

		drop_nlink(inode);

	spin_unlock(&fi->lock);

	fuse_invalidate_entry_cache(entry);

	fuse_update_ctime(inode);

}



static int fuse_unlink(struct inode *dir, struct dentry *entry)

{

	int err;
@@ -771,23 +794,8 @@ static int fuse_unlink(struct inode *dir, struct dentry *entry) 
	args.in_args[0].value = entry->d_name.name;

	err = fuse_simple_request(fm, &args);

	if (!err) {

		struct inode *inode = d_inode(entry);

		struct fuse_inode *fi = get_fuse_inode(inode);



		spin_lock(&fi->lock);

		fi->attr_version = atomic64_inc_return(&fm->fc->attr_version);

		/*

		 * If i_nlink == 0 then unlink doesn't make sense, yet this can

		 * happen if userspace filesystem is careless.  It would be

		 * difficult to enforce correct nlink usage so just ignore this

		 * condition here

		 */

		if (inode->i_nlink > 0)

			drop_nlink(inode);

		spin_unlock(&fi->lock);

		fuse_dir_changed(dir);

		fuse_invalidate_entry_cache(entry);

		fuse_update_ctime(inode);

		fuse_entry_unlinked(entry);

	} else if (err == -EINTR)

		fuse_invalidate_entry(entry);

	return err;
@@ -809,9 +817,8 @@ static int fuse_rmdir(struct inode *dir, struct dentry *entry) 
	args.in_args[0].value = entry->d_name.name;

	err = fuse_simple_request(fm, &args);

	if (!err) {

		clear_nlink(d_inode(entry));

		fuse_dir_changed(dir);

		fuse_invalidate_entry_cache(entry);

		fuse_entry_unlinked(entry);

	} else if (err == -EINTR)

		fuse_invalidate_entry(entry);

	return err;
@@ -851,10 +858,8 @@ static int fuse_rename_common(struct inode *olddir, struct dentry *oldent, 
			fuse_dir_changed(newdir);



		/* newent will end up negative */

		if (!(flags & RENAME_EXCHANGE) && d_really_is_positive(newent)) {

			fuse_invalidate_entry_cache(newent);

			fuse_update_ctime(d_inode(newent));

		}

		if (!(flags & RENAME_EXCHANGE) && d_really_is_positive(newent))

			fuse_entry_unlinked(newent);

	} else if (err == -EINTR) {

		/* If request was interrupted, DEITY only knows if the

		   rename actually took place.  If the invalidation