Extend features to 64 bit so we can use more transport bits. Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> --- drivers/lguest/lguest_device.c | 8 ++++---- drivers/s390/kvm/kvm_virtio.c | 8 ++++---- drivers/virtio/virtio.c | 8 ++++---- drivers/virtio/virtio_pci.c | 34 ++++++++++++++++++++++++++++------ drivers/virtio/virtio_ring.c | 2 ++ include/linux/virtio.h | 2 +- include/linux/virtio_config.h | 15 +++++++++------ include/linux/virtio_pci.h | 9 ++++++++- 8 files changed, 60 insertions(+), 26 deletions(-) diff --git a/drivers/lguest/lguest_device.c b/drivers/lguest/lguest_device.c index 69c84a1..d2d6953 100644 --- a/drivers/lguest/lguest_device.c +++ b/drivers/lguest/lguest_device.c @@ -93,17 +93,17 @@ static unsigned desc_size(const struct lguest_device_desc *desc) } /* This gets the device's feature bits. */ -static u32 lg_get_features(struct virtio_device *vdev) +static u64 lg_get_features(struct virtio_device *vdev) { unsigned int i; - u32 features = 0; + u64 features = 0; struct lguest_device_desc *desc = to_lgdev(vdev)->desc; u8 *in_features = lg_features(desc); /* We do this the slow but generic way. */ - for (i = 0; i < min(desc->feature_len * 8, 32); i++) + for (i = 0; i < min(desc->feature_len * 8, 64); i++) if (in_features[i / 8] & (1 << (i % 8))) - features |= (1 << i); + features |= (1ull << i); return features; } diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c index 414427d..c56293c 100644 --- a/drivers/s390/kvm/kvm_virtio.c +++ b/drivers/s390/kvm/kvm_virtio.c @@ -79,16 +79,16 @@ static unsigned desc_size(const struct kvm_device_desc *desc) } /* This gets the device's feature bits. */ -static u32 kvm_get_features(struct virtio_device *vdev) +static u64 kvm_get_features(struct virtio_device *vdev) { unsigned int i; - u32 features = 0; + u64 features = 0; struct kvm_device_desc *desc = to_kvmdev(vdev)->desc; u8 *in_features = kvm_vq_features(desc); - for (i = 0; i < min(desc->feature_len * 8, 32); i++) + for (i = 0; i < min(desc->feature_len * 8, 64); i++) if (in_features[i / 8] & (1 << (i % 8))) - features |= (1 << i); + features |= (1ull << i); return features; } diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index efb35aa..52b24d7 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -112,7 +112,7 @@ static int virtio_dev_probe(struct device *_d) struct virtio_device *dev = container_of(_d,struct virtio_device,dev); struct virtio_driver *drv = container_of(dev->dev.driver, struct virtio_driver, driver); - u32 device_features; + u64 device_features; /* We have a driver! */ add_status(dev, VIRTIO_CONFIG_S_DRIVER); @@ -124,14 +124,14 @@ static int virtio_dev_probe(struct device *_d) memset(dev->features, 0, sizeof(dev->features)); for (i = 0; i < drv->feature_table_size; i++) { unsigned int f = drv->feature_table[i]; - BUG_ON(f >= 32); - if (device_features & (1 << f)) + BUG_ON(f >= 64); + if (device_features & (1ull << f)) set_bit(f, dev->features); } /* Transport features always preserved to pass to finalize_features. */ for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++) - if (device_features & (1 << i)) + if (device_features & (1ull << i)) set_bit(i, dev->features); dev->config->finalize_features(dev); diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c index 4fb5b2b..04b216f 100644 --- a/drivers/virtio/virtio_pci.c +++ b/drivers/virtio/virtio_pci.c @@ -44,6 +44,8 @@ struct virtio_pci_device spinlock_t lock; struct list_head virtqueues; + /* 64 bit features */ + int features_hi; /* MSI-X support */ int msix_enabled; int intx_enabled; @@ -103,26 +105,46 @@ static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) } /* virtio config->get_features() implementation */ -static u32 vp_get_features(struct virtio_device *vdev) +static u64 vp_get_features(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); + u32 flo, fhi; - /* When someone needs more than 32 feature bits, we'll need to + /* When someone needs more than 32 feature bits, we need to * steal a bit to indicate that the rest are somewhere else. */ - return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES); + flo = ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES); + if (flo & (0x1 << VIRTIO_F_FEATURES_HI)) { + vp_dev->features_hi = 1; + iowrite32(0x1 << VIRTIO_F_FEATURES_HI, + vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); + fhi = ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES_HI); + } else { + vp_dev->features_hi = 0; + fhi = 0; + } + return (((u64)fhi) << 32) | flo; } /* virtio config->finalize_features() implementation */ static void vp_finalize_features(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); + u32 flo, fhi; /* Give virtio_ring a chance to accept features. */ vring_transport_features(vdev); - /* We only support 32 feature bits. */ - BUILD_BUG_ON(ARRAY_SIZE(vdev->features) != 1); - iowrite32(vdev->features[0], vp_dev->ioaddr+VIRTIO_PCI_GUEST_FEATURES); + /* We only support 64 feature bits. */ + BUILD_BUG_ON(ARRAY_SIZE(vdev->features) != 64 / BITS_PER_LONG); + flo = vdev->features[0]; + fhi = vdev->features[64 / BITS_PER_LONG - 1] >> (BITS_PER_LONG - 32); + iowrite32(flo, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); + if (flo & (0x1 << VIRTIO_F_FEATURES_HI)) { + vp_dev->features_hi = 1; + iowrite32(fhi, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES_HI); + } else { + vp_dev->features_hi = 0; + } } /* virtio config->get() implementation */ diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 8218fe6..4a7a651 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -534,6 +534,8 @@ void vring_transport_features(struct virtio_device *vdev) for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++) { switch (i) { + case VIRTIO_F_FEATURES_HI: + break; case VIRTIO_RING_F_INDIRECT_DESC: break; case VIRTIO_RING_F_EVENT_IDX: diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 58c0953..944ebcd 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -119,7 +119,7 @@ struct virtio_device { struct virtio_config_ops *config; struct list_head vqs; /* Note that this is a Linux set_bit-style bitmap. */ - unsigned long features[1]; + unsigned long features[64 / BITS_PER_LONG]; void *priv; }; diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 800617b..b1a1981 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -18,16 +18,19 @@ /* We've given up on this device. */ #define VIRTIO_CONFIG_S_FAILED 0x80 -/* Some virtio feature bits (currently bits 28 through 31) are reserved for the +/* Some virtio feature bits (currently bits 28 through 39) are reserved for the * transport being used (eg. virtio_ring), the rest are per-device feature * bits. */ #define VIRTIO_TRANSPORT_F_START 28 -#define VIRTIO_TRANSPORT_F_END 32 +#define VIRTIO_TRANSPORT_F_END 40 /* Do we get callbacks when the ring is completely used, even if we've * suppressed them? */ #define VIRTIO_F_NOTIFY_ON_EMPTY 24 +/* Enables feature bits 32 to 63 (only really required for virtio_pci). */ +#define VIRTIO_F_FEATURES_HI 31 + #ifdef __KERNEL__ #include <linux/err.h> #include <linux/virtio.h> @@ -72,7 +75,7 @@ * @del_vqs: free virtqueues found by find_vqs(). * @get_features: get the array of feature bits for this device. * vdev: the virtio_device - * Returns the first 32 feature bits (all we currently need). + * Returns the first 64 feature bits (all we currently need). * @finalize_features: confirm what device features we'll be using. * vdev: the virtio_device * This gives the final feature bits for the device: it can change @@ -92,7 +95,7 @@ struct virtio_config_ops { vq_callback_t *callbacks[], const char *names[]); void (*del_vqs)(struct virtio_device *); - u32 (*get_features)(struct virtio_device *vdev); + u64 (*get_features)(struct virtio_device *vdev); void (*finalize_features)(struct virtio_device *vdev); }; @@ -110,9 +113,9 @@ static inline bool virtio_has_feature(const struct virtio_device *vdev, { /* Did you forget to fix assumptions on max features? */ if (__builtin_constant_p(fbit)) - BUILD_BUG_ON(fbit >= 32); + BUILD_BUG_ON(fbit >= 64); else - BUG_ON(fbit >= 32); + BUG_ON(fbit >= 64); if (fbit < VIRTIO_TRANSPORT_F_START) virtio_check_driver_offered_feature(vdev, fbit); diff --git a/include/linux/virtio_pci.h b/include/linux/virtio_pci.h index 9a3d7c4..90f9725 100644 --- a/include/linux/virtio_pci.h +++ b/include/linux/virtio_pci.h @@ -55,9 +55,16 @@ /* Vector value used to disable MSI for queue */ #define VIRTIO_MSI_NO_VECTOR 0xffff +/* An extended 32-bit r/o bitmask of the features supported by the host */ +#define VIRTIO_PCI_HOST_FEATURES_HI 24 + +/* An extended 32-bit r/w bitmask of features activated by the guest */ +#define VIRTIO_PCI_GUEST_FEATURES_HI 28 + /* The remaining space is defined by each driver as the per-driver * configuration space */ -#define VIRTIO_PCI_CONFIG(dev) ((dev)->msix_enabled ? 24 : 20) +#define VIRTIO_PCI_CONFIG(dev) ((dev)->features_hi ? 32 : \ + (dev)->msix_enabled ? 24 : 20) /* Virtio ABI version, this must match exactly */ #define VIRTIO_PCI_ABI_VERSION 0 -- 1.7.5.53.gc233e -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html