From 2331d19dab7c0ea9bd8f895f9a652bf02535a8d7 Mon Sep 17 00:00:00 2001 From: Rob Norris Date: Mon, 1 Jul 2024 11:19:16 +1000 Subject: [PATCH] flush: don't report flush error when disabling flush support The first time a device returns ENOTSUP in repsonse to a flush request, we set vdev_nowritecache so we don't issue flushes in the future and instead just pretend the succeeded. However, we still return an error for the initial flush, even though we just decided such errors are meaningless! So, when setting vdev_nowritecache in response to a flush error, also reset the error code to assume success. Along the way, it seems there's no good reason for vdev_disk & vdev_geom to explicitly detect no support for flush and set vdev_nowritecache; just letting the error through to zio_vdev_io_assess() will cause it all to fall out nicely. So remove those checks. Sponsored-by: Klara, Inc. Sponsored-by: Wasabi Technology, Inc. Signed-off-by: Rob Norris --- module/os/freebsd/zfs/vdev_geom.c | 15 --------------- module/os/linux/zfs/vdev_disk.c | 3 --- module/zfs/zio.c | 7 +++++-- 3 files changed, 5 insertions(+), 20 deletions(-) diff --git a/module/os/freebsd/zfs/vdev_geom.c b/module/os/freebsd/zfs/vdev_geom.c index b7ff1063b0..7aaa42bfb1 100644 --- a/module/os/freebsd/zfs/vdev_geom.c +++ b/module/os/freebsd/zfs/vdev_geom.c @@ -1014,21 +1014,6 @@ vdev_geom_io_intr(struct bio *bp) zio->io_error = SET_ERROR(EIO); switch (zio->io_error) { - case ENOTSUP: - /* - * If we get ENOTSUP for BIO_FLUSH or BIO_DELETE we know - * that future attempts will never succeed. In this case - * we set a persistent flag so that we don't bother with - * requests in the future. - */ - switch (bp->bio_cmd) { - case BIO_FLUSH: - vd->vdev_nowritecache = B_TRUE; - break; - case BIO_DELETE: - break; - } - break; case ENXIO: if (!vd->vdev_remove_wanted) { /* diff --git a/module/os/linux/zfs/vdev_disk.c b/module/os/linux/zfs/vdev_disk.c index e69c5f3841..2c963bb05c 100644 --- a/module/os/linux/zfs/vdev_disk.c +++ b/module/os/linux/zfs/vdev_disk.c @@ -1232,9 +1232,6 @@ BIO_END_IO_PROTO(vdev_disk_io_flush_completion, bio, error) zio->io_error = -error; #endif - if (zio->io_error && (zio->io_error == EOPNOTSUPP)) - zio->io_vd->vdev_nowritecache = B_TRUE; - bio_put(bio); ASSERT3S(zio->io_error, >=, 0); if (zio->io_error) diff --git a/module/zfs/zio.c b/module/zfs/zio.c index 43e4e7ff15..7af3eb922d 100644 --- a/module/zfs/zio.c +++ b/module/zfs/zio.c @@ -4532,11 +4532,14 @@ zio_vdev_io_assess(zio_t *zio) /* * If a cache flush returns ENOTSUP or ENOTTY, we know that no future * attempts will ever succeed. In this case we set a persistent - * boolean flag so that we don't bother with it in the future. + * boolean flag so that we don't bother with it in the future, and + * then we act like the flush succeeded. */ if ((zio->io_error == ENOTSUP || zio->io_error == ENOTTY) && - zio->io_type == ZIO_TYPE_FLUSH && vd != NULL) + zio->io_type == ZIO_TYPE_FLUSH && vd != NULL) { vd->vdev_nowritecache = B_TRUE; + zio->io_error = 0; + } if (zio->io_error) zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;