From 5bfe37ca8ac8e9176bfd923d0a83802b7305d2f5 Mon Sep 17 00:00:00 2001 From: Sebastien Boeuf Date: Wed, 19 Aug 2020 18:19:41 -0400 Subject: virtio: Add get_shm_region method Virtio defines 'shared memory regions' that provide a continuously shared region between the host and guest. Provide a method to find a particular region on a device. Signed-off-by: Sebastien Boeuf Signed-off-by: Dr. David Alan Gilbert Acked-by: Michael S. Tsirkin Cc: kvm@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Cc: "Michael S. Tsirkin" Signed-off-by: Miklos Szeredi --- include/linux/virtio_config.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'include') diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 8fe857e27ef3..4b8e38c5c4d8 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -11,6 +11,11 @@ struct irq_affinity; +struct virtio_shm_region { + u64 addr; + u64 len; +}; + /** * virtio_config_ops - operations for configuring a virtio device * Note: Do not assume that a transport implements all of the operations @@ -66,6 +71,7 @@ struct irq_affinity; * the caller can then copy. * @set_vq_affinity: set the affinity for a virtqueue (optional). * @get_vq_affinity: get the affinity for a virtqueue (optional). + * @get_shm_region: get a shared memory region based on the index. */ typedef void vq_callback_t(struct virtqueue *); struct virtio_config_ops { @@ -89,6 +95,8 @@ struct virtio_config_ops { const struct cpumask *cpu_mask); const struct cpumask *(*get_vq_affinity)(struct virtio_device *vdev, int index); + bool (*get_shm_region)(struct virtio_device *vdev, + struct virtio_shm_region *region, u8 id); }; /* If driver didn't advertise the feature, it will never appear. */ @@ -251,6 +259,15 @@ int virtqueue_set_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask) return 0; } +static inline +bool virtio_get_shm_region(struct virtio_device *vdev, + struct virtio_shm_region *region, u8 id) +{ + if (!vdev->config->get_shm_region) + return false; + return vdev->config->get_shm_region(vdev, region, id); +} + static inline bool virtio_is_little_endian(struct virtio_device *vdev) { return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) || -- cgit v1.2.3 From 0dd4ff93f4c8dba016ad79384007da4938cd54a1 Mon Sep 17 00:00:00 2001 From: Sebastien Boeuf Date: Wed, 19 Aug 2020 18:19:42 -0400 Subject: virtio: Implement get_shm_region for PCI transport On PCI the shm regions are found using capability entries; find a region by searching for the capability. Signed-off-by: Sebastien Boeuf Signed-off-by: Dr. David Alan Gilbert Signed-off-by: kbuild test robot Acked-by: Michael S. Tsirkin Cc: kvm@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Cc: "Michael S. Tsirkin" Signed-off-by: Miklos Szeredi --- include/uapi/linux/virtio_pci.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/uapi/linux/virtio_pci.h b/include/uapi/linux/virtio_pci.h index 90007a1abcab..3a86f36d7e3d 100644 --- a/include/uapi/linux/virtio_pci.h +++ b/include/uapi/linux/virtio_pci.h @@ -113,6 +113,8 @@ #define VIRTIO_PCI_CAP_DEVICE_CFG 4 /* PCI configuration access */ #define VIRTIO_PCI_CAP_PCI_CFG 5 +/* Additional shared memory capability */ +#define VIRTIO_PCI_CAP_SHARED_MEMORY_CFG 8 /* This is the PCI capability header: */ struct virtio_pci_cap { @@ -121,11 +123,18 @@ struct virtio_pci_cap { __u8 cap_len; /* Generic PCI field: capability length */ __u8 cfg_type; /* Identifies the structure. */ __u8 bar; /* Where to find it. */ - __u8 padding[3]; /* Pad to full dword. */ + __u8 id; /* Multiple capabilities of the same type */ + __u8 padding[2]; /* Pad to full dword. */ __le32 offset; /* Offset within bar. */ __le32 length; /* Length of the structure, in bytes. */ }; +struct virtio_pci_cap64 { + struct virtio_pci_cap cap; + __le32 offset_hi; /* Most sig 32 bits of offset */ + __le32 length_hi; /* Most sig 32 bits of length */ +}; + struct virtio_pci_notify_cap { struct virtio_pci_cap cap; __le32 notify_off_multiplier; /* Multiplier for queue_notify_off. */ -- cgit v1.2.3 From 38e895487afc2ed42c11045853cbb3fa20b52b6e Mon Sep 17 00:00:00 2001 From: Sebastien Boeuf Date: Wed, 19 Aug 2020 18:19:43 -0400 Subject: virtio: Implement get_shm_region for MMIO transport On MMIO a new set of registers is defined for finding SHM regions. Add their definitions and use them to find the region. Signed-off-by: Sebastien Boeuf Cc: kvm@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Cc: "Michael S. Tsirkin" Signed-off-by: Miklos Szeredi --- include/uapi/linux/virtio_mmio.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include') diff --git a/include/uapi/linux/virtio_mmio.h b/include/uapi/linux/virtio_mmio.h index c4b09689ab64..0650f91bea6c 100644 --- a/include/uapi/linux/virtio_mmio.h +++ b/include/uapi/linux/virtio_mmio.h @@ -122,6 +122,17 @@ #define VIRTIO_MMIO_QUEUE_USED_LOW 0x0a0 #define VIRTIO_MMIO_QUEUE_USED_HIGH 0x0a4 +/* Shared memory region id */ +#define VIRTIO_MMIO_SHM_SEL 0x0ac + +/* Shared memory region length, 64 bits in two halves */ +#define VIRTIO_MMIO_SHM_LEN_LOW 0x0b0 +#define VIRTIO_MMIO_SHM_LEN_HIGH 0x0b4 + +/* Shared memory region base address, 64 bits in two halves */ +#define VIRTIO_MMIO_SHM_BASE_LOW 0x0b8 +#define VIRTIO_MMIO_SHM_BASE_HIGH 0x0bc + /* Configuration atomicity value */ #define VIRTIO_MMIO_CONFIG_GENERATION 0x0fc -- cgit v1.2.3