On Mon, Feb 03, 2025 at 10:43:08AM +0100, Christoph Hellwig wrote:
> Support using the ioend structure to defer I/O completion for
> reads in addition to writes. This requires a check for the operation
> to not merge reads and writes, and for buffere I/O a call into the
buffered
> buffered read I/O completion handler from iomap_finish_ioend. For
> direct I/O the existing call into the direct I/O completion handler
> handles reads just fine already.
Otherwise everything looks ok to me.
--D
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> fs/iomap/buffered-io.c | 23 ++++++++++++++++++-----
> fs/iomap/internal.h | 3 ++-
> fs/iomap/ioend.c | 6 +++++-
> 3 files changed, 25 insertions(+), 7 deletions(-)
>
> diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
> index eaffa23eb8e4..06990e012884 100644
> --- a/fs/iomap/buffered-io.c
> +++ b/fs/iomap/buffered-io.c
> @@ -306,14 +306,27 @@ static void iomap_finish_folio_read(struct folio *folio, size_t off,
> folio_end_read(folio, uptodate);
> }
>
> -static void iomap_read_end_io(struct bio *bio)
> +static u32 __iomap_read_end_io(struct bio *bio, int error)
> {
> - int error = blk_status_to_errno(bio->bi_status);
> struct folio_iter fi;
> + u32 folio_count = 0;
>
> - bio_for_each_folio_all(fi, bio)
> + bio_for_each_folio_all(fi, bio) {
> iomap_finish_folio_read(fi.folio, fi.offset, fi.length, error);
> + folio_count++;
> + }
> bio_put(bio);
> + return folio_count;
> +}
> +
> +static void iomap_read_end_io(struct bio *bio)
> +{
> + __iomap_read_end_io(bio, blk_status_to_errno(bio->bi_status));
> +}
> +
> +u32 iomap_finish_ioend_buffered_read(struct iomap_ioend *ioend)
> +{
> + return __iomap_read_end_io(&ioend->io_bio, ioend->io_error);
> }
>
> struct iomap_readpage_ctx {
> @@ -1568,7 +1581,7 @@ static void iomap_finish_folio_write(struct inode *inode, struct folio *folio,
> * state, release holds on bios, and finally free up memory. Do not use the
> * ioend after this.
> */
> -u32 iomap_finish_ioend_buffered(struct iomap_ioend *ioend)
> +u32 iomap_finish_ioend_buffered_write(struct iomap_ioend *ioend)
> {
> struct inode *inode = ioend->io_inode;
> struct bio *bio = &ioend->io_bio;
> @@ -1600,7 +1613,7 @@ static void iomap_writepage_end_bio(struct bio *bio)
> struct iomap_ioend *ioend = iomap_ioend_from_bio(bio);
>
> ioend->io_error = blk_status_to_errno(bio->bi_status);
> - iomap_finish_ioend_buffered(ioend);
> + iomap_finish_ioend_buffered_write(ioend);
> }
>
> /*
> diff --git a/fs/iomap/internal.h b/fs/iomap/internal.h
> index f6992a3bf66a..c824e74a3526 100644
> --- a/fs/iomap/internal.h
> +++ b/fs/iomap/internal.h
> @@ -4,7 +4,8 @@
>
> #define IOEND_BATCH_SIZE 4096
>
> -u32 iomap_finish_ioend_buffered(struct iomap_ioend *ioend);
> +u32 iomap_finish_ioend_buffered_read(struct iomap_ioend *ioend);
> +u32 iomap_finish_ioend_buffered_write(struct iomap_ioend *ioend);
> u32 iomap_finish_ioend_direct(struct iomap_ioend *ioend);
>
> #endif /* _IOMAP_INTERNAL_H */
> diff --git a/fs/iomap/ioend.c b/fs/iomap/ioend.c
> index 18894ebba6db..2dd29403dc10 100644
> --- a/fs/iomap/ioend.c
> +++ b/fs/iomap/ioend.c
> @@ -44,7 +44,9 @@ static u32 iomap_finish_ioend(struct iomap_ioend *ioend, int error)
> return 0;
> if (ioend->io_flags & IOMAP_IOEND_DIRECT)
> return iomap_finish_ioend_direct(ioend);
> - return iomap_finish_ioend_buffered(ioend);
> + if (bio_op(&ioend->io_bio) == REQ_OP_READ)
> + return iomap_finish_ioend_buffered_read(ioend);
> + return iomap_finish_ioend_buffered_write(ioend);
> }
>
> /*
> @@ -83,6 +85,8 @@ EXPORT_SYMBOL_GPL(iomap_finish_ioends);
> static bool iomap_ioend_can_merge(struct iomap_ioend *ioend,
> struct iomap_ioend *next)
> {
> + if (bio_op(&ioend->io_bio) != bio_op(&next->io_bio))
> + return false;
> if (ioend->io_bio.bi_status != next->io_bio.bi_status)
> return false;
> if (next->io_flags & IOMAP_IOEND_BOUNDARY)
> --
> 2.45.2
>
>
