[PATCH RFC v2 3/4] virtio: allow finalize_features to fail

Michael S. Tsirkin
2014-12-04T18:44:42Z

This will make it easy for transports to validate features and return
failure.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
include/linux/virtio_config.h | 3 ++-
drivers/lguest/lguest_device.c | 4 +++-
drivers/misc/mic/card/mic_virtio.c | 4 +++-
drivers/remoteproc/remoteproc_virtio.c | 4 +++-
drivers/s390/kvm/kvm_virtio.c | 4 +++-
drivers/s390/kvm/virtio_ccw.c | 6 ++++--
drivers/virtio/virtio.c | 4 +++-
drivers/virtio/virtio_mmio.c | 4 +++-
drivers/virtio/virtio_pci.c | 4 +++-
9 files changed, 27 insertions(+), 10 deletions(-)

diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 1fa5faa..7979f85 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -47,6 +47,7 @@
* vdev: the virtio_device
* This gives the final feature bits for the device: it can change
* the dev->feature bits if it wants.
+ * Returns 0 on success or error status
* @bus_name: return the bus name associated with the device
* vdev: the virtio_device
* This returns a pointer to the bus name a la pci_name from which
@@ -68,7 +69,7 @@ struct virtio_config_ops {
const char *names[]);
void (*del_vqs)(struct virtio_device *);
u64 (*get_features)(struct virtio_device *vdev);
- void (*finalize_features)(struct virtio_device *vdev);
+ int (*finalize_features)(struct virtio_device *vdev);
const char *(*bus_name)(struct virtio_device *vdev);
int (*set_vq_affinity)(struct virtqueue *vq, int cpu);
};
diff --git a/drivers/lguest/lguest_device.c b/drivers/lguest/lguest_device.c
index 9b77b66..89088d6 100644
--- a/drivers/lguest/lguest_device.c
+++ b/drivers/lguest/lguest_device.c
@@ -126,7 +126,7 @@ static void status_notify(struct virtio_device *vdev)
* sorted out, this routine is called so we can tell the Host which features we
* understand and accept.
*/
-static void lg_finalize_features(struct virtio_device *vdev)
+static int lg_finalize_features(struct virtio_device *vdev)
{
unsigned int i, bits;
struct lguest_device_desc *desc = to_lgdev(vdev)->desc;
@@ -153,6 +153,8 @@ static void lg_finalize_features(struct virtio_device *vdev)

/* Tell Host we've finished with this device's feature negotiation */
status_notify(vdev);
+
+ return 0;
}

/* Once they've found a field, getting a copy of it is easy. */
diff --git a/drivers/misc/mic/card/mic_virtio.c b/drivers/misc/mic/card/mic_virtio.c
index d027d29..e486a0c 100644
--- a/drivers/misc/mic/card/mic_virtio.c
+++ b/drivers/misc/mic/card/mic_virtio.c
@@ -84,7 +84,7 @@ static u64 mic_get_features(struct virtio_device *vdev)
return features;
}

-static void mic_finalize_features(struct virtio_device *vdev)
+static int mic_finalize_features(struct virtio_device *vdev)
{
unsigned int i, bits;
struct mic_device_desc __iomem *desc = to_micvdev(vdev)->desc;
@@ -107,6 +107,8 @@ static void mic_finalize_features(struct virtio_device *vdev)
iowrite8(ioread8(&out_features[i / 8]) | (1 << (i % 8)),
&out_features[i / 8]);
}
+
+ return 0;
}

/*
diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c
index 627737e..e1a1023 100644
--- a/drivers/remoteproc/remoteproc_virtio.c
+++ b/drivers/remoteproc/remoteproc_virtio.c
@@ -217,7 +217,7 @@ static u64 rproc_virtio_get_features(struct virtio_device *vdev)
return rsc->dfeatures;
}

-static void rproc_virtio_finalize_features(struct virtio_device *vdev)
+static int rproc_virtio_finalize_features(struct virtio_device *vdev)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
struct fw_rsc_vdev *rsc;
@@ -235,6 +235,8 @@ static void rproc_virtio_finalize_features(struct virtio_device *vdev)
* to the remote processor once it is powered on.
*/
rsc->gfeatures = vdev->features;
+
+ return 0;
}

static void rproc_virtio_get(struct virtio_device *vdev, unsigned offset,
diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
index f5575cc..dd65c8b 100644
--- a/drivers/s390/kvm/kvm_virtio.c
+++ b/drivers/s390/kvm/kvm_virtio.c
@@ -93,7 +93,7 @@ static u64 kvm_get_features(struct virtio_device *vdev)
return features;
}

-static void kvm_finalize_features(struct virtio_device *vdev)
+static int kvm_finalize_features(struct virtio_device *vdev)
{
unsigned int i, bits;
struct kvm_device_desc *desc = to_kvmdev(vdev)->desc;
@@ -112,6 +112,8 @@ static void kvm_finalize_features(struct virtio_device *vdev)
if (__virtio_test_bit(vdev, i))
out_features[i / 8] |= (1 << (i % 8));
}
+
+ return 0;
}

/*
diff --git a/drivers/s390/kvm/virtio_ccw.c b/drivers/s390/kvm/virtio_ccw.c
index c792b5f..789275f 100644
--- a/drivers/s390/kvm/virtio_ccw.c
+++ b/drivers/s390/kvm/virtio_ccw.c
@@ -752,7 +752,7 @@ out_free:
return rc;
}

-static void virtio_ccw_finalize_features(struct virtio_device *vdev)
+static int virtio_ccw_finalize_features(struct virtio_device *vdev)
{
struct virtio_ccw_device *vcdev = to_vc_device(vdev);
struct virtio_feature_desc *features;
@@ -760,7 +760,7 @@ static void virtio_ccw_finalize_features(struct virtio_device *vdev)

ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
if (!ccw)
- return;
+ return 0;

features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
if (!features)
@@ -793,6 +793,8 @@ static void virtio_ccw_finalize_features(struct virtio_device *vdev)
out_free:
kfree(features);
kfree(ccw);
+
+ return 0;
}

static void virtio_ccw_get_config(struct virtio_device *vdev,
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 6b4c1113..7ddebbc 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -211,7 +211,9 @@ static int virtio_dev_probe(struct device *_d)
if (device_features & (1ULL << i))
__virtio_set_bit(dev, i);

- dev->config->finalize_features(dev);
+ err = dev->config->finalize_features(dev);
+ if (err)
+ goto err;

if (virtio_has_feature(dev, VIRTIO_F_VERSION_1)) {
add_status(dev, VIRTIO_CONFIG_S_FEATURES_OK);
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index aec1dae..5219210 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -152,7 +152,7 @@ static u64 vm_get_features(struct virtio_device *vdev)
return readl(vm_dev->base + VIRTIO_MMIO_HOST_FEATURES);
}

-static void vm_finalize_features(struct virtio_device *vdev)
+static int vm_finalize_features(struct virtio_device *vdev)
{
struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);

@@ -164,6 +164,8 @@ static void vm_finalize_features(struct virtio_device *vdev)

writel(0, vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES_SEL);
writel(vdev->features, vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES);
+
+ return 0;
}

static void vm_get(struct virtio_device *vdev, unsigned offset,
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 98f9c6e..c7649f3 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -111,7 +111,7 @@ static u64 vp_get_features(struct virtio_device *vdev)
}

/* virtio config->finalize_features() implementation */
-static void vp_finalize_features(struct virtio_device *vdev)
+static int vp_finalize_features(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);

@@ -124,6 +124,8 @@ static void vp_finalize_features(struct virtio_device *vdev)
/* We only support 32 feature bits. */
iowrite32(vdev->features, vp_dev->ioaddr +
VIRTIO_PCI_LEGACY_GUEST_FEATURES);
+
+ return 0;
}

/* virtio config->get() implementation */
--
MST