From: "Michael S. Tsirkin" <mst@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: Jason Wang <jasowang@redhat.com>,
virtualization@lists.linux-foundation.org
Subject: [PATCH v3 19/38] vdpa: make sure set_features is invoked for legacy
Date: Wed, 5 Aug 2020 09:44:07 -0400 [thread overview]
Message-ID: <20200805134226.1106164-20-mst@redhat.com> (raw)
In-Reply-To: <20200805134226.1106164-1-mst@redhat.com>
Some legacy guests just assume features are 0 after reset.
We detect that config space is accessed before features are
set and set features to 0 automatically.
Note: some legacy guests might not even access config space, if this is
reported in the field we might need to catch a kick to handle these.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/vdpa/vdpa.c | 1 +
include/linux/vdpa.h | 34 ++++++++++++++++++++++++++++++++++
2 files changed, 35 insertions(+)
diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index de211ef3738c..7105265e4793 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -96,6 +96,7 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
vdev->dev.release = vdpa_release_dev;
vdev->index = err;
vdev->config = config;
+ vdev->features_valid = false;
err = dev_set_name(&vdev->dev, "vdpa%u", vdev->index);
if (err)
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 239db794357c..29b8296f1414 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -33,12 +33,14 @@ struct vdpa_notification_area {
* @dma_dev: the actual device that is performing DMA
* @config: the configuration ops for this device.
* @index: device index
+ * @features_valid: were features initialized? for legacy guests
*/
struct vdpa_device {
struct device dev;
struct device *dma_dev;
const struct vdpa_config_ops *config;
unsigned int index;
+ bool features_valid;
};
/**
@@ -266,4 +268,36 @@ static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev)
{
return vdev->dma_dev;
}
+
+static inline void vdpa_reset(struct vdpa_device *vdev)
+{
+ const struct vdpa_config_ops *ops = vdev->config;
+
+ vdev->features_valid = false;
+ ops->set_status(vdev, 0);
+}
+
+static inline int vdpa_set_features(struct vdpa_device *vdev, u64 features)
+{
+ const struct vdpa_config_ops *ops = vdev->config;
+
+ vdev->features_valid = true;
+ return ops->set_features(vdev, features);
+}
+
+
+static inline void vdpa_get_config(struct vdpa_device *vdev, unsigned offset,
+ void *buf, unsigned int len)
+{
+ const struct vdpa_config_ops *ops = vdev->config;
+
+ /*
+ * Config accesses aren't supposed to trigger before features are set.
+ * If it does happen we assume a legacy guest.
+ */
+ if (!vdev->features_valid)
+ vdpa_set_features(vdev, 0);
+ ops->get_config(vdev, offset, buf, len);
+}
+
#endif /* _LINUX_VDPA_H */
--
MST
next prev parent reply other threads:[~2020-08-05 17:13 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-05 13:43 [PATCH v3 00/38] virtio: config space endian-ness cleanup Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 01/38] virtio_balloon: fix sparse warning Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 02/38] virtio_ring: sparse warning fixup Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 03/38] virtio: allow __virtioXX, __leXX in config space Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 04/38] virtio_9p: correct tags for config space fields Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 05/38] virtio_balloon: " Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 06/38] virtio_blk: " Michael S. Tsirkin
2020-08-05 14:24 ` Stefano Garzarella
2020-08-05 13:43 ` [PATCH v3 07/38] virtio_console: " Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 08/38] virtio_crypto: " Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 09/38] virtio_fs: " Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 10/38] virtio_gpu: " Michael S. Tsirkin
2020-08-07 11:22 ` Gerd Hoffmann
2020-08-05 13:43 ` [PATCH v3 11/38] virtio_input: " Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 12/38] virtio_iommu: " Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 13/38] virtio_mem: " Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 14/38] virtio_net: " Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 15/38] virtio_pmem: " Michael S. Tsirkin
2020-08-05 13:43 ` [PATCH v3 16/38] virtio_scsi: " Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 17/38] virtio_config: disallow native type fields Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 18/38] mlxbf-tmfifo: sparse tags for config access Michael S. Tsirkin
2020-08-05 14:24 ` Andy Shevchenko
2020-08-05 13:44 ` Michael S. Tsirkin [this message]
2020-08-05 13:44 ` [PATCH v3 20/38] vhost/vdpa: switch to new helpers Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 21/38] virtio_vdpa: legacy features handling Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 22/38] vdpa_sim: fix endian-ness of config space Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 23/38] virtio_config: cread/write cleanup Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 24/38] virtio_config: rewrite using _Generic Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 25/38] virtio_config: disallow native type fields (again) Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 26/38] virtio_config: LE config space accessors Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 27/38] virtio_caif: correct tags for config space fields Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 28/38] virtio_config: add virtio_cread_le_feature Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 29/38] virtio_balloon: use LE config space accesses Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 30/38] virtio_input: convert to LE accessors Michael S. Tsirkin
2020-08-19 5:59 ` Gerd Hoffmann
2020-08-05 13:44 ` [PATCH v3 31/38] virtio_fs: " Michael S. Tsirkin
2020-08-06 17:28 ` Vivek Goyal
2020-08-05 13:44 ` [PATCH v3 32/38] virtio_crypto: " Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 33/38] virtio_pmem: " Michael S. Tsirkin
2020-08-07 20:05 ` Ira Weiny
2020-08-05 13:44 ` [PATCH v3 34/38] drm/virtio: " Michael S. Tsirkin
2020-08-07 11:22 ` Gerd Hoffmann
2020-08-05 13:44 ` [PATCH v3 35/38] virtio_mem: " Michael S. Tsirkin
2020-08-10 7:57 ` David Hildenbrand
2020-08-05 13:44 ` [PATCH v3 36/38] virtio-iommu: " Michael S. Tsirkin
2020-08-05 13:44 ` [PATCH v3 37/38] virtio_config: drop LE option from config space Michael S. Tsirkin
2020-08-05 13:45 ` [PATCH v3 38/38] virtio_net: use LE accessors for speed/duplex Michael S. Tsirkin
2020-08-05 13:59 ` Cornelia Huck
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