On 20/01/2023 22:46, Elliot Berman wrote:
Add Gunyah Resource Manager RPC to launch an unauthenticated VM.
Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx>
---
drivers/virt/gunyah/Makefile | 2 +-
drivers/virt/gunyah/rsc_mgr.h | 36 +++++
drivers/virt/gunyah/rsc_mgr_rpc.c | 238 ++++++++++++++++++++++++++++++
include/linux/gunyah_rsc_mgr.h | 55 +++++++
4 files changed, 330 insertions(+), 1 deletion(-)
create mode 100644 drivers/virt/gunyah/rsc_mgr_rpc.c
diff --git a/drivers/virt/gunyah/Makefile b/drivers/virt/gunyah/Makefile
index cc864ff5abbb..de29769f2f3f 100644
--- a/drivers/virt/gunyah/Makefile
+++ b/drivers/virt/gunyah/Makefile
@@ -2,5 +2,5 @@
obj-$(CONFIG_GUNYAH) += gunyah.o
-gunyah_rsc_mgr-y += rsc_mgr.o
+gunyah_rsc_mgr-y += rsc_mgr.o rsc_mgr_rpc.o
obj-$(CONFIG_GUNYAH) += gunyah_rsc_mgr.o
diff --git a/drivers/virt/gunyah/rsc_mgr.h b/drivers/virt/gunyah/rsc_mgr.h
index 824749e63a54..2f12f31a2ea6 100644
--- a/drivers/virt/gunyah/rsc_mgr.h
+++ b/drivers/virt/gunyah/rsc_mgr.h
@@ -68,4 +68,40 @@ struct gh_rm;
int gh_rm_call(struct gh_rm *rsc_mgr, u32 message_id, void *req_buff, size_t req_buff_size,
void **resp_buf, size_t *resp_buff_size);
+/* Message IDs: VM Management */
+#define GH_RM_RPC_VM_ALLOC_VMID 0x56000001
+#define GH_RM_RPC_VM_DEALLOC_VMID 0x56000002
+#define GH_RM_RPC_VM_START 0x56000004
+#define GH_RM_RPC_VM_STOP 0x56000005
+#define GH_RM_RPC_VM_CONFIG_IMAGE 0x56000009
+#define GH_RM_RPC_VM_INIT 0x5600000B
+#define GH_RM_RPC_VM_GET_HYP_RESOURCES 0x56000020
+#define GH_RM_RPC_VM_GET_VMID 0x56000024
+
+struct gh_vm_common_vmid_req {
+ __le16 vmid;
+ __le16 reserved0;
+} __packed;
+
+/* Call: VM_STOP */
+struct gh_vm_stop_req {
+ __le16 vmid;
+ u8 flags; /* currently not used */
+ u8 reserved;
+ __le32 stop_reason; /* currently not used */
+} __packed;
+
+/* Call: VM_CONFIG_IMAGE */
+struct gh_vm_config_image_req {
+ __le16 vmid;
+ __le16 auth_mech;
+ __le32 mem_handle;
+ __le64 image_offset;
+ __le64 image_size;
+ __le64 dtb_offset;
+ __le64 dtb_size;
+} __packed;
+
+/* Call: GET_HYP_RESOURCES */
+
#endif
diff --git a/drivers/virt/gunyah/rsc_mgr_rpc.c b/drivers/virt/gunyah/rsc_mgr_rpc.c
new file mode 100644
index 000000000000..b6935dfac1fe
--- /dev/null
+++ b/drivers/virt/gunyah/rsc_mgr_rpc.c
@@ -0,0 +1,238 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/gunyah_rsc_mgr.h>
+
+#include "rsc_mgr.h"
+
+/*
+ * Several RM calls take only a VMID as a parameter and give only standard
+ * response back. Deduplicate boilerplate code by using this common call.
+ */
+static int gh_rm_common_vmid_call(struct gh_rm *rm, u32 message_id, u16 vmid)
+{
+ void *resp;
+ struct gh_vm_common_vmid_req req_payload = {
+ .vmid = cpu_to_le16(vmid),
+ };
+ size_t resp_size;
+ int ret;
+
+ ret = gh_rm_call(rm, message_id, &req_payload, sizeof(req_payload), &resp, &resp_size);
+ if (!ret && resp_size) {
Am struggling to understand these type of checks in success case, when a
command is not expecting any response why are we checking for response
here, This sounds like a bug in either RM or hypervisor.
Or Is this something that happens due to some firmware behaviour?
Could you elobrate on this.
+ pr_warn("Unexpected payload size: %ld Expected: 0", resp_size);
+ dump_stack();
+ kfree(resp);
+ return -EBADMSG;
+ }
+
+ return ret;
+}
+
+/**
+ * gh_rm_alloc_vmid() - Allocate a new VM in Gunyah. Returns the VM identifier.
+ * @vmid: Use GH_VMID_INVAL or GH_VMID_SELF (0) to dynamically allocate a VM. A reserved VMID can
+ * be supplied to request allocation of a platform-defined VM.
+ *
+ * Returns - the allocated VMID or negative value on error
+ */
+int gh_rm_alloc_vmid(struct gh_rm *rm, u16 vmid)
+{
+ void *resp;
+ struct gh_vm_common_vmid_req req_payload = {
+ .vmid = cpu_to_le16(vmid),
we pass vmid that is recevied here.
+ };
+ struct gh_vm_alloc_vmid_resp *resp_payload;
+ size_t resp_size;
+ int ret;
+
+ if (vmid == GH_VMID_INVAL)
+ vmid = 0;
then we change this to 0.
+
+ ret = gh_rm_call(rm, GH_RM_RPC_VM_ALLOC_VMID, &req_payload, sizeof(req_payload), &resp,
+ &resp_size);
+ if (ret)
+ return ret;
+
+ if (!vmid) {
then here we check agaist zero.
Why not just do
if (vmid == GH_VMID_INVAL || vmid == GH_VMID_SELF)
this will make core more reader friendly and match to what is in kerneldoc.
+ if (resp_size != sizeof(*resp_payload)) {
+ pr_warn("%s: unexpected payload size: %ld Expected: %ld", __func__,
+ resp_size, sizeof(*resp_payload));
+ ret = -EBADMSG;
+ } else {
+ resp_payload = resp;
+ ret = le16_to_cpu(resp_payload->vmid);
+ }
+ }
+ kfree(resp);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gh_rm_alloc_vmid);
+
+/**
+ * gh_rm_dealloc_vmid() - Dispose the VMID
+ * @vmid: VM identifier
+ */
+int gh_rm_dealloc_vmid(struct gh_rm *rm, u16 vmid)
+{
+ return gh_rm_common_vmid_call(rm, GH_RM_RPC_VM_DEALLOC_VMID, vmid);
+}
+EXPORT_SYMBOL_GPL(gh_rm_dealloc_vmid);
+
+/**
+ * gh_rm_vm_start() - Move the VM into "ready to run" state
+ * @vmid: VM identifier
+ *
+ * On VMs which use proxy scheduling, vcpu_run is needed to actually run the VM.
+ * On VMs which use Gunyah's scheduling, the vCPUs start executing in accordance with Gunyah
+ * scheduling policies.
+ */
+int gh_rm_vm_start(struct gh_rm *rm, u16 vmid)
+{
+ return gh_rm_common_vmid_call(rm, GH_RM_RPC_VM_START, vmid);
+}
+EXPORT_SYMBOL_GPL(gh_rm_vm_start);
+
+/**
+ * gh_rm_vm_stop() - Send a request to Resource Manager VM to stop a VM.
+ * @vmid: VM identifier
+ *
+ * Returns - 0 on success; negative value on failure
+ */
+int gh_rm_vm_stop(struct gh_rm *rm, u16 vmid)
+{
+ struct gh_vm_stop_req req_payload = {
+ .vmid = cpu_to_le16(vmid),
+ };
+ void *resp;
+ size_t resp_size;
+ int ret;
+
+ ret = gh_rm_call(rm, GH_RM_RPC_VM_STOP, &req_payload, sizeof(req_payload),
+ &resp, &resp_size);
+ if (!ret && resp_size) {
same comment as the first one.
+ pr_warn("%s: unexpected payload size: %ld Expected: 0", __func__, resp_size);
+ kfree(resp);
+ return -EBADMSG;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gh_rm_vm_stop);
+
+int gh_rm_vm_configure(struct gh_rm *rm, u16 vmid, enum gh_rm_vm_auth_mechanism auth_mechanism,
+ u32 mem_handle, u64 image_offset, u64 image_size, u64 dtb_offset, u64 dtb_size)
+{
+ struct gh_vm_config_image_req req_payload = { 0 };
+ void *resp;
+ size_t resp_size;
+ int ret;
+
+ req_payload.vmid = cpu_to_le16(vmid);
+ req_payload.auth_mech = cpu_to_le16(auth_mechanism);
+ req_payload.mem_handle = cpu_to_le32(mem_handle);
+ req_payload.image_offset = cpu_to_le64(image_offset);
+ req_payload.image_size = cpu_to_le64(image_size);
+ req_payload.dtb_offset = cpu_to_le64(dtb_offset);
+ req_payload.dtb_size = cpu_to_le64(dtb_size);
+
+ ret = gh_rm_call(rm, GH_RM_RPC_VM_CONFIG_IMAGE, &req_payload, sizeof(req_payload),
+ &resp, &resp_size);
+ if (!ret && resp_size) {
same comment as the first one.
+ pr_warn("%s: unexpected payload size: %ld Expected: 0", __func__, resp_size);
+ kfree(resp);
+ return -EBADMSG;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gh_rm_vm_configure);
+
+/**
+ * gh_rm_vm_init() - Move the VM to initialized state.
+ * @vmid: VM identifier
+ *
+ * RM will allocate needed resources for the VM. After gh_rm_vm_init, gh_rm_get_hyp_resources()
+ * can be called to learn of the capabilities we can use with the new VM.
+ *
+ * Returns - 0 on success; negative value on failure
+ */
+int gh_rm_vm_init(struct gh_rm *rm, u16 vmid)
+{
+ return gh_rm_common_vmid_call(rm, GH_RM_RPC_VM_INIT, vmid);
+}
+EXPORT_SYMBOL_GPL(gh_rm_vm_init);
+
+/**
+ * gh_rm_get_hyp_resources() - Retrieve hypervisor resources (capabilities) associated with a VM
+ * @vmid: VMID of the other VM to get the resources of
+ * @resources: Set by gh_rm_get_hyp_resources and contains the returned hypervisor resources.
+ *
+ * Returns - 0 on success; negative value on failure
+ */
+int gh_rm_get_hyp_resources(struct gh_rm *rm, u16 vmid,
+ struct gh_rm_hyp_resources **resources)
+{
+ struct gh_rm_hyp_resources *resp;
+ size_t resp_size;
+ int ret;
+ struct gh_vm_common_vmid_req req_payload = {
+ .vmid = cpu_to_le16(vmid),
+ };
+
+ ret = gh_rm_call(rm, GH_RM_RPC_VM_GET_HYP_RESOURCES,
+ &req_payload, sizeof(req_payload),
+ (void **)&resp, &resp_size);
we can go upto 100 chars.
+ if (ret)
+ return ret;
+
+ if (!resp_size)
+ return -EBADMSG;
This is again another check that falls under the first category, how can
a command pass and return incorrect responses?
Or are we doing to many unnecessary checks?
+
+ if (resp_size < struct_size(resp, entries, 0) ||
+ resp_size != struct_size(resp, entries, le32_to_cpu(resp->n_entries))) {
+ kfree(resp);
+ return -EBADMSG;
+ }
+
+ *resources = resp;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(gh_rm_get_hyp_resources);
+
+/**
+ * gh_rm_get_vmid() - Retrieve VMID of this virtual machine
+ * @vmid: Filled with the VMID of this VM
+ */
+int gh_rm_get_vmid(struct gh_rm *rm, u16 *vmid)
+{
+ static u16 cached_vmid = GH_VMID_INVAL;
+ __le16 *resp;
+ size_t resp_size;
+ int ret;
+
+ if (cached_vmid != GH_VMID_INVAL) {
+ *vmid = cached_vmid;
+ return 0;
+ }
+
+ ret = gh_rm_call(rm, GH_RM_RPC_VM_GET_VMID, NULL, 0, (void **)&resp, &resp_size);
+ if (ret)
+ return ret;
+
+ if (resp_size != sizeof(*resp)) {
+ pr_warn("%s: unexpected payload size: %ld Expected: %ld", __func__,
+ resp_size, sizeof(*resp));
+ ret = -EBADMSG;
+ goto out;
+ }
+
+ *vmid = cached_vmid = le16_to_cpu(*resp);
+out:
+ kfree(resp);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gh_rm_get_vmid);
