2024-04-11 13:33:12

by Sebastian Ene

[permalink] [raw]
Subject: [PATCH v2] KVM: arm64: Add support for FFA_PARTITION_INFO_GET

Handle the FFA_PARTITION_INFO_GET host call inside the pKVM hypervisor
and copy the response message back to the host buffers. Save the
returned FF-A version as we will need it later to interpret the response
from the TEE.

Signed-off-by: Sebastian Ene <[email protected]>
---
arch/arm64/kvm/hyp/nvhe/ffa.c | 45 +++++++++++++++++++++++++++++++++++
1 file changed, 45 insertions(+)

diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c
index 320f2eaa14a9..31ad740137fd 100644
--- a/arch/arm64/kvm/hyp/nvhe/ffa.c
+++ b/arch/arm64/kvm/hyp/nvhe/ffa.c
@@ -67,6 +67,7 @@ struct kvm_ffa_buffers {
*/
static struct kvm_ffa_buffers hyp_buffers;
static struct kvm_ffa_buffers host_buffers;
+static u32 ffa_version;

static void ffa_to_smccc_error(struct arm_smccc_res *res, u64 ffa_errno)
{
@@ -640,6 +641,45 @@ static bool do_ffa_features(struct arm_smccc_res *res,
return true;
}

+static void do_ffa_part_get(struct arm_smccc_res *res,
+ struct kvm_cpu_context *ctxt)
+{
+ DECLARE_REG(u32, uuid0, ctxt, 1);
+ DECLARE_REG(u32, uuid1, ctxt, 2);
+ DECLARE_REG(u32, uuid2, ctxt, 3);
+ DECLARE_REG(u32, uuid3, ctxt, 4);
+ DECLARE_REG(u32, flags, ctxt, 5);
+ u32 count, sz;
+
+ hyp_spin_lock(&host_buffers.lock);
+ if (!host_buffers.rx) {
+ ffa_to_smccc_res(res, FFA_RET_INVALID_PARAMETERS);
+ goto out_unlock;
+ }
+
+ arm_smccc_1_1_smc(FFA_PARTITION_INFO_GET, uuid0, uuid1,
+ uuid2, uuid3, flags, 0, 0,
+ res);
+
+ if (res->a0 != FFA_SUCCESS)
+ goto out_unlock;
+
+ count = res->a2;
+ if (!count)
+ goto out_unlock;
+
+ /* FFA_VERSION_1_0 lacks the size in the response */
+ if (ffa_version > FFA_VERSION_1_0)
+ sz = res->a3;
+ else
+ sz = 8;
+
+ WARN_ON(count * sz > PAGE_SIZE);
+ memcpy(host_buffers.rx, hyp_buffers.rx, count * sz);
+out_unlock:
+ hyp_spin_unlock(&host_buffers.lock);
+}
+
bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id)
{
struct arm_smccc_res res;
@@ -686,6 +726,9 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id)
case FFA_MEM_FRAG_TX:
do_ffa_mem_frag_tx(&res, host_ctxt);
goto out_handled;
+ case FFA_PARTITION_INFO_GET:
+ do_ffa_part_get(&res, host_ctxt);
+ goto out_handled;
}

if (ffa_call_supported(func_id))
@@ -726,6 +769,8 @@ int hyp_ffa_init(void *pages)
if (FFA_MAJOR_VERSION(res.a0) != 1)
return -EOPNOTSUPP;

+ ffa_version = res.a0;
+
arm_smccc_1_1_smc(FFA_ID_GET, 0, 0, 0, 0, 0, 0, 0, &res);
if (res.a0 != FFA_SUCCESS)
return -EOPNOTSUPP;
--
2.44.0.478.gd926399ef9-goog