[PATCH 5/6] iomap: Lift blocksize restriction on atomic writes

From: Ritesh Harjani (IBM)
Date: Thu Oct 24 2024 - 23:47:54 EST


Filesystems like ext4 can submit writes in multiples of blocksizes.
But we still can't allow the writes to be split. Hence let's check if
the iomap_length() is same as iter->len or not.

This shouldn't affect XFS since it anyways checks for this in
xfs_file_write_iter() to not support atomic write size request of more
than FS blocksize.

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>
---
fs/iomap/direct-io.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index ed4764e3b8f0..1d33b4239b3e 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -306,7 +306,7 @@ static loff_t iomap_dio_bio_iter(const struct iomap_iter *iter,
size_t copied = 0;
size_t orig_count;

- if (atomic && length != fs_block_size)
+ if (atomic && length != iter->len)
return -EINVAL;

if ((pos | length) & (bdev_logical_block_size(iomap->bdev) - 1) ||
--
2.46.0