Re: [rfc][patch 4/4] fs: tmpfs, ext2 use new truncate

[Christoph Hellwig <hch@infradead.org>]

I'd still prefer this to be split into one patch for shmem, and one for
ext2 to make bisecting easier.

> @@ -68,7 +70,7 @@ void ext2_delete_inode (struct inode * i
>  
>  	inode->i_size = 0;
>  	if (inode->i_blocks)
> -		ext2_truncate (inode);
> +		ext2_truncate_blocks(inode, 0);
>  	ext2_free_inode (inode);
>  
>  	return;

> -void ext2_truncate(struct inode *inode)
> +static void ext2_truncate_blocks(struct inode *inode, loff_t offset)
>  {
>  	__le32 *i_data = EXT2_I(inode)->i_data;
>  	struct ext2_inode_info *ei = EXT2_I(inode);
> @@ -1032,27 +1074,8 @@ void ext2_truncate(struct inode *inode)
>  	int n;
>  	long iblock;
>  	unsigned blocksize;
> -
> -	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
> -	    S_ISLNK(inode->i_mode)))
> -		return;
> -	if (ext2_inode_is_fast_symlink(inode))
> -		return;
> -	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
> -		return;
> -

We can't move this to the caller easily.  ext2_delete_inode gets
called for all inodes, but we only want to go on truncating for the
limited set that passes this check.



> -	if (mapping_is_xip(inode->i_mapping))
> -		xip_truncate_page(inode->i_mapping, inode->i_size);
> -	else if (test_opt(inode->i_sb, NOBH))
> -		nobh_truncate_page(inode->i_mapping,
> -				inode->i_size, ext2_get_block);
> -	else
> -		block_truncate_page(inode->i_mapping,
> -				inode->i_size, ext2_get_block);

The patch header should have an explanation for why we don't need this
anymore for the various existing callers.