From: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Instead of looping with ZERO_PAGE, use a huge zero folio to zero pad the
block. Fallback to ZERO_PAGE if mm_get_huge_zero_folio() fails.
Suggested-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
---
I rebased on top of mm-unstable to get mm_get_huge_zero_folio().
@Christoph is this inline with what you had in mind?
fs/iomap/direct-io.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 5f481068de5b..7f584f9ff2c5 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -236,11 +236,18 @@ static void iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio,
loff_t pos, unsigned len)
{
struct inode *inode = file_inode(dio->iocb->ki_filp);
- struct page *page = ZERO_PAGE(0);
+ struct folio *zero_page_folio = page_folio(ZERO_PAGE(0));
+ struct folio *folio = zero_page_folio;
struct bio *bio;
WARN_ON_ONCE(len > (BIO_MAX_VECS * PAGE_SIZE));
+ if (len > PAGE_SIZE) {
+ folio = mm_get_huge_zero_folio(current->mm);
+ if (!folio)
+ folio = zero_page_folio;
+ }
+
bio = iomap_dio_alloc_bio(iter, dio, BIO_MAX_VECS,
REQ_OP_WRITE | REQ_SYNC | REQ_IDLE);
fscrypt_set_bio_crypt_ctx(bio, inode, pos >> inode->i_blkbits,
@@ -251,10 +258,10 @@ static void iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio,
bio->bi_end_io = iomap_dio_bio_end_io;
while (len) {
- unsigned int io_len = min_t(unsigned int, len, PAGE_SIZE);
+ unsigned int size = min(len, folio_size(folio));
- __bio_add_page(bio, page, io_len, 0);
- len -= io_len;
+ bio_add_folio_nofail(bio, folio, size, 0);
+ len -= size;
}
iomap_dio_submit_bio(iter, dio, bio, pos);
}
--
2.34.1
