[PATCH RFCv2 1/8] backends/iommufd: Introduce helper function iommufd_device_get_hw_capabilities()

[Joao Martins <joao.m.martins@oracle.com>]

The new helper will fetch vendor agnostic IOMMU capabilities supported
both by hardware and software. Right now it is only iommu dirty
tracking.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
---
 backends/iommufd.c       | 25 +++++++++++++++++++++++++
 include/sysemu/iommufd.h |  2 ++
 2 files changed, 27 insertions(+)

diff --git a/backends/iommufd.c b/backends/iommufd.c
index d92791bba935..8486894f1b3f 100644
--- a/backends/iommufd.c
+++ b/backends/iommufd.c
@@ -237,3 +237,28 @@ void iommufd_device_init(IOMMUFDDevice *idev)
     host_iommu_base_device_init(&idev->base, HID_IOMMUFD,
                                 sizeof(IOMMUFDDevice));
 }
+
+int iommufd_device_get_hw_capabilities(IOMMUFDDevice *idev, uint64_t *caps,
+                                       Error **errp)
+{
+    struct iommu_hw_info info = {
+        .size = sizeof(info),
+        .flags = 0,
+        .dev_id = idev->devid,
+        .data_len = 0,
+        .__reserved = 0,
+        .data_uptr = 0,
+        .out_capabilities = 0,
+    };
+    int ret;
+
+    ret = ioctl(idev->iommufd->fd, IOMMU_GET_HW_INFO, &info);
+    if (ret) {
+        error_setg_errno(errp, errno,
+                         "Failed to get hardware info capabilities");
+    } else {
+        *caps = info.out_capabilities;
+    }
+
+    return ret;
+}
diff --git a/include/sysemu/iommufd.h b/include/sysemu/iommufd.h
index c3f346976039..4afe97307dbe 100644
--- a/include/sysemu/iommufd.h
+++ b/include/sysemu/iommufd.h
@@ -47,4 +47,6 @@ typedef struct IOMMUFDDevice {
 } IOMMUFDDevice;
 
 void iommufd_device_init(IOMMUFDDevice *idev);
+int iommufd_device_get_hw_capabilities(IOMMUFDDevice *idev, uint64_t *caps,
+                                       Error **errp);
 #endif
-- 
2.39.3