On 2/7/2023 6:43 AM, Srinivas Kandagatla wrote:
On 20/01/2023 22:46, Elliot Berman wrote:
Gunyah allows host virtual machines to schedule guest virtual machines
and handle their MMIO accesses. vCPUs are presented to the host as a
Gunyah resource and represented to userspace as a Gunyah VM function.
Creating the vcpu VM function will create a file descriptor that:
- can run an ioctl: GH_VCPU_RUN to schedule the guest vCPU until the
next interrupt occurs on the host or when the guest vCPU can no
longer be run.
- can be mmap'd to share a gh_vcpu_run structure which can look up the
reason why GH_VCPU_RUN returned and provide return values for MMIO
access.
Co-developed-by: Prakruthi Deepak Heragu <quic_pheragu@xxxxxxxxxxx>
Signed-off-by: Prakruthi Deepak Heragu <quic_pheragu@xxxxxxxxxxx>
Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx>
---
Documentation/virt/gunyah/vm-manager.rst | 30 +-
arch/arm64/gunyah/gunyah_hypercall.c | 28 ++
drivers/virt/gunyah/Kconfig | 11 +
drivers/virt/gunyah/Makefile | 2 +
drivers/virt/gunyah/gunyah_vcpu.c | 358 +++++++++++++++++++++++
drivers/virt/gunyah/vm_mgr.c | 25 ++
drivers/virt/gunyah/vm_mgr.h | 1 +
include/linux/gunyah.h | 7 +
include/uapi/linux/gunyah.h | 30 ++
9 files changed, 490 insertions(+), 2 deletions(-)
create mode 100644 drivers/virt/gunyah/gunyah_vcpu.c
...
diff --git a/include/uapi/linux/gunyah.h b/include/uapi/linux/gunyah.h
index ec8da6fde045..b4afb11f538a 100644
--- a/include/uapi/linux/gunyah.h
+++ b/include/uapi/linux/gunyah.h
@@ -53,9 +53,14 @@ struct gh_vm_dtb_config {
#define GUNYAH_FUNCTION_NAME_SIZE 32
#define GUNYAH_FUNCTION_MAX_ARG_SIZE 1024
+struct gh_fn_vcpu_arg {
+ __u32 vcpu_id;
+};
+
struct gh_vm_function {
char name[GUNYAH_FUNCTION_NAME_SIZE];
union {
+ struct gh_device_vcpu_arg vcpu;
char data[GUNYAH_FUNCTION_MAX_ARG_SIZE];
};
};
@@ -63,4 +68,29 @@ struct gh_vm_function {
#define GH_VM_ADD_FUNCTION _IOW(GH_IOCTL_TYPE, 0x4, struct
gh_vm_function)
#define GH_VM_REMOVE_FUNCTION _IOW(GH_IOCTL_TYPE, 0x7, struct
gh_vm_function)
+/* for GH_VCPU_RUN, returned by mmap(vcpu_fd, offset=0) */
+struct gh_vcpu_run {
this looks unused, I dont see any reference to this.
This structure gets mapped into userspace from the vCPU file descriptor,
similar principle to KVM.
Thanks,
Elliot
+ /* in */
+ __u8 immediate_exit;
+ __u8 padding1[7];
+
+ /* out */
+#define GH_VM_EXIT_UNKNOWN 0
+#define GH_VM_EXIT_MMIO 1
+ __u32 exit_reason;
If this is ment to go in any of the ioctl arguments then this suffers
same issue of padding.
+
+ union {
+ /* GH_VM_EXIT_MMIO */
+ struct {
+ __u64 phys_addr;
+ __u8 data[8];
+ __u32 len;
+ __u8 is_write;
+ } mmio;
+ };
+};
+
+#define GH_VCPU_RUN _IO(GH_IOCTL_TYPE, 0x5)
+#define GH_VCPU_MMAP_SIZE _IO(GH_IOCTL_TYPE, 0x6)
+
#endif
