diff mbox series

[RFCv3,5/7] iomap: Fix iomap_adjust_read_range for plen calculation

Message ID deb8991ce9aa1850b82471cf3e76cd8fdc1a9e92.1714046808.git.ritesh.list@gmail.com (mailing list archive)
State New, archived
Headers show
Series ext2 iomap changes and iomap improvements | expand

Commit Message

Ritesh Harjani (IBM) April 25, 2024, 1:28 p.m. UTC
If the extent spans the block that contains the i_size, we need to
handle both halves separately but only when the i_size is within the
current folio under processing.
"orig_pos + length > isize" can be true for all folios if the mapped
extent length is greater than the folio size. That is making plen to
break for every folio instead of only the last folio.

So use orig_plen for checking if "orig_pos + orig_plen > isize".

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
cc: Ojaswin Mujoo <ojaswin@linux.ibm.com>
---
 fs/iomap/buffered-io.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Christoph Hellwig April 26, 2024, 6:49 a.m. UTC | #1
On Thu, Apr 25, 2024 at 06:58:49PM +0530, Ritesh Harjani (IBM) wrote:
> If the extent spans the block that contains the i_size, we need to

s/the i_size/i_size/.

> handle both halves separately

.. so that we properly zero data in the page cache for blocks that are
entirely outside of i_size.

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>
Ritesh Harjani (IBM) April 26, 2024, 8:52 a.m. UTC | #2
Christoph Hellwig <hch@infradead.org> writes:

> On Thu, Apr 25, 2024 at 06:58:49PM +0530, Ritesh Harjani (IBM) wrote:
>> If the extent spans the block that contains the i_size, we need to
>
> s/the i_size/i_size/.
>
>> handle both halves separately
>
> .. so that we properly zero data in the page cache for blocks that are
> entirely outside of i_size.

Sure. 

>
> Otherwise looks good:
>
> Reviewed-by: Christoph Hellwig <hch@lst.de>

Thanks for the review.

-ritesh
Darrick J. Wong April 26, 2024, 3:43 p.m. UTC | #3
On Fri, Apr 26, 2024 at 02:22:25PM +0530, Ritesh Harjani wrote:
> Christoph Hellwig <hch@infradead.org> writes:
> 
> > On Thu, Apr 25, 2024 at 06:58:49PM +0530, Ritesh Harjani (IBM) wrote:
> >> If the extent spans the block that contains the i_size, we need to
> >
> > s/the i_size/i_size/.
> >
> >> handle both halves separately
> >
> > .. so that we properly zero data in the page cache for blocks that are
> > entirely outside of i_size.
> 
> Sure. 
> 
> >
> > Otherwise looks good:
> >
> > Reviewed-by: Christoph Hellwig <hch@lst.de>
> 
> Thanks for the review.

With Christoph's comments addressed, you can also add
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> 
> -ritesh
>
diff mbox series

Patch

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 4e8e41c8b3c0..9f79c82d1f73 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -241,6 +241,7 @@  static void iomap_adjust_read_range(struct inode *inode, struct folio *folio,
 	unsigned block_size = (1 << block_bits);
 	size_t poff = offset_in_folio(folio, *pos);
 	size_t plen = min_t(loff_t, folio_size(folio) - poff, length);
+	size_t orig_plen = plen;
 	unsigned first = poff >> block_bits;
 	unsigned last = (poff + plen - 1) >> block_bits;
 
@@ -277,7 +278,7 @@  static void iomap_adjust_read_range(struct inode *inode, struct folio *folio,
 	 * handle both halves separately so that we properly zero data in the
 	 * page cache for blocks that are entirely outside of i_size.
 	 */
-	if (orig_pos <= isize && orig_pos + length > isize) {
+	if (orig_pos <= isize && orig_pos + orig_plen > isize) {
 		unsigned end = offset_in_folio(folio, isize - 1) >> block_bits;
 
 		if (first <= end && last > end)