Re: [PATCH v6 06/11] filemap: cap PTE range to be created to allowed zero fill in folio_map_range()

[Hannes Reinecke]

On 5/29/24 15:45, Pankaj Raghav (Samsung) wrote:
> From: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
>
> Usually the page cache does not extend beyond the size of the inode,
> therefore, no PTEs are created for folios that extend beyond the size.
>
> But with LBS support, we might extend page cache beyond the size of the
> inode as we need to guarantee folios of minimum order. Cap the PTE range
> to be created for the page cache up to the max allowed zero-fill file
> end, which is aligned to the PAGE_SIZE.
>
> An fstests test has been created to trigger this edge case [0].
>
> [0] https://lore.kernel.org/fstests/20240415081054.1782715-1-mcgrof@xxxxxxxxxx/
>
> Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
> Signed-off-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
> ---
>   mm/filemap.c | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>

Cheers,

Hannes
--
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@xxxxxxx                                +49 911 74053 688
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