| Message ID | 20230328022928.1003996-3-dmitry.fomichev@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | virtio-blk: fix a few problems in ZBD-related code | expand |
On Mon, Mar 27, 2023 at 10:29:28PM -0400, Dmitry Fomichev wrote: > When the kernel is built without support for zoned block devices, > virtio-blk probe needs to error out any host-managed device scans > to prevent such devices from appearing in the system as non-zoned. > The current virtio-blk code simply bypasses all ZBD checks if > CONFIG_BLK_DEV_ZONED is not defined and this leads to host-managed > block devices being presented as non-zoned in the OS. This is one of > the main problems this patch series is aimed to fix. > > In this patch, make VIRTIO_BLK_F_ZONED feature defined even when > CONFIG_BLK_DEV_ZONED is not. This change makes the code compliant with > the voted revision of virtio-blk ZBD spec. Modify the probe code to > look at the situation when VIRTIO_BLK_F_ZONED is negotiated in a kernel > that is built without ZBD support. In this case, the code checks > the zoned model of the device and fails the probe is the device > is host-managed. > > The patch also adds the comment to clarify that the call to perform > the zoned device probe is correctly placed after virtio_device ready(). > > Fixes: 95bfec41bd3d ("virtio-blk: add support for zoned block devices") > Cc: stable@vger.kernel.org > Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com> > --- > drivers/block/virtio_blk.c | 34 ++++++++++++++++++---------------- > 1 file changed, 18 insertions(+), 16 deletions(-) Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
On 3/28/23 11:29, Dmitry Fomichev wrote: > When the kernel is built without support for zoned block devices, > virtio-blk probe needs to error out any host-managed device scans > to prevent such devices from appearing in the system as non-zoned. > The current virtio-blk code simply bypasses all ZBD checks if > CONFIG_BLK_DEV_ZONED is not defined and this leads to host-managed > block devices being presented as non-zoned in the OS. This is one of > the main problems this patch series is aimed to fix. > > In this patch, make VIRTIO_BLK_F_ZONED feature defined even when > CONFIG_BLK_DEV_ZONED is not. This change makes the code compliant with > the voted revision of virtio-blk ZBD spec. Modify the probe code to > look at the situation when VIRTIO_BLK_F_ZONED is negotiated in a kernel > that is built without ZBD support. In this case, the code checks > the zoned model of the device and fails the probe is the device > is host-managed. > > The patch also adds the comment to clarify that the call to perform > the zoned device probe is correctly placed after virtio_device ready(). > > Fixes: 95bfec41bd3d ("virtio-blk: add support for zoned block devices") > Cc: stable@vger.kernel.org > Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com> One nit below, but otherwise looks good to me. Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> > -static inline bool virtblk_has_zoned_feature(struct virtio_device *vdev) > -{ > - return false; > + u8 model; > + > + virtio_cread(vdev, struct virtio_blk_config, zoned.model, &model); > + if (model == VIRTIO_BLK_Z_HM) { > + dev_err(&vdev->dev, > + "zoned devices are not supported by the kernel"); May be simply: "Zoned devices are not supported" Or: "Support for zoned devices is disabled"
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 0b49fd2bd3bf..6d2674aa0551 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -867,16 +867,12 @@ static int virtblk_probe_zoned_device(struct virtio_device *vdev, return ret; } -static inline bool virtblk_has_zoned_feature(struct virtio_device *vdev) -{ - return virtio_has_feature(vdev, VIRTIO_BLK_F_ZONED); -} - #else /* * Zoned block device support is not configured in this kernel. - * We only need to define a few symbols to avoid compilation errors. + * Host-managed zoned devices can't be supported, but others are good + * to go as regular block devices. */ #define virtblk_report_zones NULL static inline void virtblk_revalidate_zones(struct virtio_blk *vblk) @@ -885,11 +881,16 @@ static inline void virtblk_revalidate_zones(struct virtio_blk *vblk) static inline int virtblk_probe_zoned_device(struct virtio_device *vdev, struct virtio_blk *vblk, struct request_queue *q) { - return -EOPNOTSUPP; -} -static inline bool virtblk_has_zoned_feature(struct virtio_device *vdev) -{ - return false; + u8 model; + + virtio_cread(vdev, struct virtio_blk_config, zoned.model, &model); + if (model == VIRTIO_BLK_Z_HM) { + dev_err(&vdev->dev, + "zoned devices are not supported by the kernel"); + return -EOPNOTSUPP; + } + + return 0; } #endif /* CONFIG_BLK_DEV_ZONED */ @@ -1575,7 +1576,11 @@ static int virtblk_probe(struct virtio_device *vdev) virtblk_update_capacity(vblk, false); virtio_device_ready(vdev); - if (virtblk_has_zoned_feature(vdev)) { + /* + * All steps that follow use the VQs therefore they need to be + * placed after the virtio_device_ready() call above. + */ + if (virtio_has_feature(vdev, VIRTIO_BLK_F_ZONED)) { err = virtblk_probe_zoned_device(vdev, vblk, q); if (err) goto out_cleanup_disk; @@ -1681,10 +1686,7 @@ static unsigned int features[] = { VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE, VIRTIO_BLK_F_MQ, VIRTIO_BLK_F_DISCARD, VIRTIO_BLK_F_WRITE_ZEROES, - VIRTIO_BLK_F_SECURE_ERASE, -#ifdef CONFIG_BLK_DEV_ZONED - VIRTIO_BLK_F_ZONED, -#endif /* CONFIG_BLK_DEV_ZONED */ + VIRTIO_BLK_F_SECURE_ERASE, VIRTIO_BLK_F_ZONED, }; static struct virtio_driver virtio_blk = {
When the kernel is built without support for zoned block devices, virtio-blk probe needs to error out any host-managed device scans to prevent such devices from appearing in the system as non-zoned. The current virtio-blk code simply bypasses all ZBD checks if CONFIG_BLK_DEV_ZONED is not defined and this leads to host-managed block devices being presented as non-zoned in the OS. This is one of the main problems this patch series is aimed to fix. In this patch, make VIRTIO_BLK_F_ZONED feature defined even when CONFIG_BLK_DEV_ZONED is not. This change makes the code compliant with the voted revision of virtio-blk ZBD spec. Modify the probe code to look at the situation when VIRTIO_BLK_F_ZONED is negotiated in a kernel that is built without ZBD support. In this case, the code checks the zoned model of the device and fails the probe is the device is host-managed. The patch also adds the comment to clarify that the call to perform the zoned device probe is correctly placed after virtio_device ready(). Fixes: 95bfec41bd3d ("virtio-blk: add support for zoned block devices") Cc: stable@vger.kernel.org Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com> --- drivers/block/virtio_blk.c | 34 ++++++++++++++++++---------------- 1 file changed, 18 insertions(+), 16 deletions(-)