On 18:41 19/06, Christoph Hellwig wrote:
> This will be used by gfs2 to attach data to transactions for the journaled
> data mode. But the concept is generic enough that we might be able to
> use it for other purposes like encryption/integrity post-processing in the
> future.
>
> Based on a patch from Andreas Gruenbacher.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> fs/iomap.c | 3 +++
> include/linux/iomap.h | 9 +++++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/fs/iomap.c b/fs/iomap.c
> index 4aecd7c5dbd8..a1f71e64ea49 100644
> --- a/fs/iomap.c
> +++ b/fs/iomap.c
> @@ -201,6 +201,9 @@ iomap_write_end(struct inode *inode, loff_t pos, unsigned len,
> copied, page, NULL);
> }
>
> + if (iomap->page_done)
> + iomap->page_done(inode, pos, copied, page, iomap);
> +
> if (ret < len)
> iomap_write_failed(inode, pos, len);
> return ret;
> diff --git a/include/linux/iomap.h b/include/linux/iomap.h
> index 10d6cff7f69a..45f43865b0f0 100644
> --- a/include/linux/iomap.h
> +++ b/include/linux/iomap.h
> @@ -9,6 +9,7 @@ struct fiemap_extent_info;
> struct inode;
> struct iov_iter;
> struct kiocb;
> +struct page;
> struct vm_area_struct;
> struct vm_fault;
>
> @@ -56,6 +57,14 @@ struct iomap {
> struct block_device *bdev; /* block device for I/O */
> struct dax_device *dax_dev; /* dax_dev for dax operations */
> void *inline_data;
> +
> + /*
> + * Called when finished processing a page in the mapping returned in
> + * this iomap. At least for now this is only supported in the buffered
> + * write path.
> + */
> + void (*page_done)(struct inode *inode, loff_t pos, unsigned copied,
> + struct page *page, struct iomap *iomap);
> };
>
Would it be better if we keep this function as a part of iomap_ops? I
know gfs2 sets this conditionally, but we can always check the condition
in the function assigned to page_done(). It would keep all the functions
in one place.
--
Goldwyn
