diff mbox series

[05/24] DAX: virtio: Add shared memory capability

Message ID 20210209190224.62827-6-dgilbert@redhat.com (mailing list archive)
State New, archived
Headers show
Series virtiofs dax patches | expand

Commit Message

Dr. David Alan Gilbert (git) Feb. 9, 2021, 7:02 p.m. UTC
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Define a new capability type 'VIRTIO_PCI_CAP_SHARED_MEMORY_CFG'
and the data structure 'virtio_pci_cap64' to go with it.
They allow defining shared memory regions with sizes and offsets
of 2^32 and more.
Multiple instances of the capability are allowed and distinguished
by the 'id' field in the base capability.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 hw/virtio/virtio-pci.c | 20 ++++++++++++++++++++
 hw/virtio/virtio-pci.h |  4 ++++
 2 files changed, 24 insertions(+)

Comments

Stefan Hajnoczi Feb. 11, 2021, 10:17 a.m. UTC | #1
On Tue, Feb 09, 2021 at 07:02:05PM +0000, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> 
> Define a new capability type 'VIRTIO_PCI_CAP_SHARED_MEMORY_CFG'
> and the data structure 'virtio_pci_cap64' to go with it.
> They allow defining shared memory regions with sizes and offsets
> of 2^32 and more.
> Multiple instances of the capability are allowed and distinguished
> by the 'id' field in the base capability.
> 
> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> ---
>  hw/virtio/virtio-pci.c | 20 ++++++++++++++++++++
>  hw/virtio/virtio-pci.h |  4 ++++
>  2 files changed, 24 insertions(+)

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
diff mbox series

Patch

diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 094c36aa3e..de378c594e 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -1138,6 +1138,26 @@  static int virtio_pci_add_mem_cap(VirtIOPCIProxy *proxy,
     return offset;
 }
 
+int virtio_pci_add_shm_cap(VirtIOPCIProxy *proxy,
+                           uint8_t bar, uint64_t offset, uint64_t length,
+                           uint8_t id)
+{
+    struct virtio_pci_cap64 cap = {
+        .cap.cap_len = sizeof cap,
+        .cap.cfg_type = VIRTIO_PCI_CAP_SHARED_MEMORY_CFG,
+    };
+    uint32_t mask32 = ~0;
+
+    cap.cap.bar = bar;
+    cap.cap.id = id;
+    cap.cap.length = cpu_to_le32(length & mask32);
+    cap.length_hi = cpu_to_le32((length >> 32) & mask32);
+    cap.cap.offset = cpu_to_le32(offset & mask32);
+    cap.offset_hi = cpu_to_le32((offset >> 32) & mask32);
+
+    return virtio_pci_add_mem_cap(proxy, &cap.cap);
+}
+
 static uint64_t virtio_pci_common_read(void *opaque, hwaddr addr,
                                        unsigned size)
 {
diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h
index d7d5d403a9..31ca339099 100644
--- a/hw/virtio/virtio-pci.h
+++ b/hw/virtio/virtio-pci.h
@@ -247,4 +247,8 @@  void virtio_pci_types_register(const VirtioPCIDeviceTypeInfo *t);
  */
 unsigned virtio_pci_optimal_num_queues(unsigned fixed_queues);
 
+int virtio_pci_add_shm_cap(VirtIOPCIProxy *proxy,
+                           uint8_t bar, uint64_t offset, uint64_t length,
+                           uint8_t id);
+
 #endif