Re: [PATCH v1 0/3] fuse: clean up offset and page count calculations

["Darrick J. Wong" <djwong@kernel.org>]

On Fri, Jan 16, 2026 at 03:56:03PM -0800, Joanne Koong wrote:
> This patchset aims to improve code clarity by using standard kernel helper
> macros for common calculations:
>  * DIV_ROUND_UP() for page count calculations
>  * offset_in_folio() for large folio offset calculations
>  * offset_in_page() for page offset calculations
> 
> These helpers improve readability and consistency with patterns used
> elsewhere in the kernel. No functional changes intended.
> 
> This patchset is on top of Jingbo's patch in [1].

As a straight conversion this looks fine to me so
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

OTOH I just learned that fuse has a backchannel for fuse servers to
inject pagecache data for a regular file.  That might be kinda nice for
an HSM or something?  Though that would be covered by FUSE_READ.

Hrmm, I wonder how well that interacts with iomap... we don't mark the
folios dirty or update timestamps, so I'm guessing the contents could
disappear at any time if the page cache gets reclaimed?

Weiiiird.....

--D


> Thanks,
> Joanne
> 
> [1] https://lore.kernel.org/linux-fsdevel/20260115023607.77349-1-jefflexu@linux.alibaba.com/
> 
> Joanne Koong (3):
>   fuse: use DIV_ROUND_UP() for page count calculations
>   fuse: use offset_in_folio() for large folio offset calculations
>   fuse: use offset_in_page() for page offset calculations
> 
>  fs/fuse/dev.c     | 14 +++++++-------
>  fs/fuse/file.c    |  2 +-
>  fs/fuse/readdir.c |  8 ++++----
>  3 files changed, 12 insertions(+), 12 deletions(-)
> 
> -- 
> 2.47.3
> 
>