From c1f54ec477fdb42e8f454759c7df44f5fb67e58a Mon Sep 17 00:00:00 2001 From: Fuad Tabba Date: Wed, 16 Nov 2022 17:03:28 +0000 Subject: [PATCH] FROMLIST: KVM: arm64: Handle FFA_FEATURES call from the host Filter out advertising unsupported features, and only advertise features and properties that are supported by the hypervisor proxy. Bug: 254811097 Change-Id: I071766d6d241f4bdd00b8f80e6b237c184a1e59a Signed-off-by: Fuad Tabba Signed-off-by: Quentin Perret Link: https://lore.kernel.org/r/20221116170335.2341003-6-qperret@google.com --- arch/arm64/kvm/hyp/nvhe/ffa.c | 44 +++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c index 969d72390844..d199f868583e 100644 --- a/arch/arm64/kvm/hyp/nvhe/ffa.c +++ b/arch/arm64/kvm/hyp/nvhe/ffa.c @@ -45,6 +45,16 @@ static void ffa_to_smccc_error(struct arm_smccc_res *res, u64 ffa_errno) }; } +static void ffa_to_smccc_res_prop(struct arm_smccc_res *res, int ret, u64 prop) +{ + if (ret == FFA_RET_SUCCESS) { + *res = (struct arm_smccc_res) { .a0 = FFA_SUCCESS, + .a2 = prop }; + } else { + ffa_to_smccc_error(res, ret); + } +} + static void ffa_set_retval(struct kvm_cpu_context *ctxt, struct arm_smccc_res *res) { @@ -89,6 +99,35 @@ static bool ffa_call_unsupported(u64 func_id) return false; } +static bool do_ffa_features(struct arm_smccc_res *res, + struct kvm_cpu_context *ctxt) +{ + DECLARE_REG(u32, id, ctxt, 1); + u64 prop = 0; + int ret = 0; + + if (ffa_call_unsupported(id)) { + ret = FFA_RET_NOT_SUPPORTED; + goto out_handled; + } + + switch (id) { + case FFA_MEM_SHARE: + case FFA_FN64_MEM_SHARE: + case FFA_MEM_LEND: + case FFA_FN64_MEM_LEND: + ret = FFA_RET_SUCCESS; + prop = 0; /* No support for dynamic buffers */ + goto out_handled; + default: + return false; + } + +out_handled: + ffa_to_smccc_res_prop(res, ret, prop); + return true; +} + bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt) { DECLARE_REG(u64, func_id, host_ctxt, 0); @@ -98,6 +137,10 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt) return false; switch (func_id) { + case FFA_FEATURES: + if (!do_ffa_features(&res, host_ctxt)) + return false; + goto out_handled; /* Memory management */ case FFA_FN64_RXTX_MAP: case FFA_RXTX_UNMAP: @@ -114,6 +157,7 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt) return false; /* Pass through */ ffa_to_smccc_error(&res, FFA_RET_NOT_SUPPORTED); +out_handled: ffa_set_retval(host_ctxt, &res); return true; }