virtio: allow finalize_features to fail

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

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/lguest/lguest_device.c b/drivers/lguest/lguest_device.c
index 9b77b66..89088d6 100644 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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 224f854..e1673a5 100644 (file)
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -212,7 +212,9 @@ 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);
@@ -354,6 +356,7 @@ EXPORT_SYMBOL_GPL(virtio_device_freeze);
 int virtio_device_restore(struct virtio_device *dev)
 {
        struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+       int ret;
 
        /* We always start by resetting the device, in case a previous
         * driver messed it up. */
@@ -373,14 +376,14 @@ int virtio_device_restore(struct virtio_device *dev)
        /* We have a driver! */
        add_status(dev, VIRTIO_CONFIG_S_DRIVER);
 
-       dev->config->finalize_features(dev);
+       ret = dev->config->finalize_features(dev);
+       if (ret)
+               goto err;
 
        if (drv->restore) {
-               int ret = drv->restore(dev);
-               if (ret) {
-                       add_status(dev, VIRTIO_CONFIG_S_FAILED);
-                       return ret;
-               }
+               ret = drv->restore(dev);
+               if (ret)
+                       goto err;
        }
 
        /* Finally, tell the device we're all set */
@@ -389,6 +392,10 @@ int virtio_device_restore(struct virtio_device *dev)
        virtio_config_enable(dev);
 
        return 0;
+
+err:
+       add_status(dev, VIRTIO_CONFIG_S_FAILED);
+       return ret;
 }
 EXPORT_SYMBOL_GPL(virtio_device_restore);
 #endif

diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index aec1dae..5219210 100644 (file)
--- 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 dd6df97..9be59d9 100644 (file)
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -112,7 +112,7 @@ 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_GUEST_FEATURES);
+
+       return 0;
 }
 
 /* virtio config->get() implementation */

diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 1fa5faa..7979f85 100644 (file)
--- 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);
 };