Re: [PATCH 4/5] ext4: implement ext4_fiemap

[Andreas Dilger <adilger@sun.com>]

On May 24, 2008  17:02 -0700, Mark Fasheh wrote:
> +#define EXT4_FIEMAP_FLAG_INCOMPAT_UNSUPP (FIEMAP_FLAG_INCOMPAT &	\
> +					  ~(FIEMAP_FLAG_LUN_OFFSET))

Per discussion with Eric, this needs to be changed:

#define EXT4_FIEMAP_FLAG_SUPP (FIEMAP_FLAG_NUM_EXTENTS | FIEMAP_FLAG_SYNC | \
			       FIEMAP_FLAG_HSM_READ | FIEMAP_FLAG_LUN_ORDER)


> +struct fiemap_internal {
> +	struct fiemap		*fiemap_s;
> +	struct fiemap_extent	fm_extent;
> +	char			*cur_ext_ptr;
> +	int			err;
> +};

This is no longer used and can be removed (now uses fiemap_extent_info).

> +/*
> + * Callback function called for each extent to gather FIEMAP information.
> + */
> +int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
> +		       struct ext4_ext_cache *newex, struct ext4_extent *ex,
> +		       void *data)
> +{
> +	/* Just counting extents? */
> +	if (fieinfo->fi_flags & FIEMAP_FLAG_NUM_EXTENTS) {
> +		fieinfo->fi_extents_mapped++;
> +		return EXT_CONTINUE;
> +	}

This isn't needed anymore, fiemap_fill_next_extent() handles it.


> +int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
> +		__u64 start, __u64 len)
> +{
> +	/* fallback to generic here if not extents */
> +#warning fix bitmap fallback
> +	if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
> +		return -EOPNOTSUPP;

	if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
		return generic_block_fiemap(inode, fieinfo, start, len,
					    ext4_get_block);

> +#if 0
> +	/* bail on unsupported flags for this fs */
> +	if (fiemap_s->fm_flags & EXT4_FIEMAP_FLAG_INCOMPAT_UNSUPP)
> +		return -EOPNOTSUPP;
> +#endif

This should be reinstated now that we have come to a decision on the flags:

	if (fieinfo->fi_flags & ~EXT4_FIEMAP_FLAG_SUPP) {
		fieinfo->fi_flags &= ~EXT4_FIEMAP_FLAG_SUPP;
		return -EBADF;
	}


Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.