Merge branch kvm-arm64/ffa-1p1 into kvmarm/next

* kvm-arm64/ffa-1p1:
  : Improvements to the pKVM FF-A Proxy, courtesy of Sebastian Ene
  :
  : Various minor improvements to how host FF-A calls are proxied with the
  : TEE, along with support for v1.1 of the protocol.
  KVM: arm64: Use FF-A 1.1 with pKVM
  KVM: arm64: Update the identification range for the FF-A smcs
  KVM: arm64: Add support for FFA_PARTITION_INFO_GET
  KVM: arm64: Trap FFA_VERSION host call in pKVM

Signed-off-by: Oliver Upton <[email protected]>

Author: oupton

arch/arm64/kvm/hyp/include/nvhe/ffa.h

@@ -9,7 +9,7 @@
 #include <asm/kvm_host.h>
 
 #define FFA_MIN_FUNC_NUM 0x60
-#define FFA_MAX_FUNC_NUM 0x7F
+#define FFA_MAX_FUNC_NUM 0xFF
 
 int hyp_ffa_init(void *pages);
 bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id);

arch/arm64/kvm/hyp/nvhe/ffa.c

@@ -67,6 +67,9 @@ struct kvm_ffa_buffers {
  */
 static struct kvm_ffa_buffers hyp_buffers;
 static struct kvm_ffa_buffers host_buffers;
+static u32 hyp_ffa_version;
+static bool has_version_negotiated;
+static hyp_spinlock_t version_lock;
 
 static void ffa_to_smccc_error(struct arm_smccc_res *res, u64 ffa_errno)
 {
@@ -454,7 +457,7 @@ static __always_inline void do_ffa_mem_xfer(const u64 func_id,
 	memcpy(buf, host_buffers.tx, fraglen);
 
 	ep_mem_access = (void *)buf +
-			ffa_mem_desc_offset(buf, 0, FFA_VERSION_1_0);
+			ffa_mem_desc_offset(buf, 0, hyp_ffa_version);
 	offset = ep_mem_access->composite_off;
 	if (!offset || buf->ep_count != 1 || buf->sender_id != HOST_FFA_ID) {
 		ret = FFA_RET_INVALID_PARAMETERS;
@@ -533,7 +536,7 @@ static void do_ffa_mem_reclaim(struct arm_smccc_res *res,
 	fraglen = res->a2;
 
 	ep_mem_access = (void *)buf +
-			ffa_mem_desc_offset(buf, 0, FFA_VERSION_1_0);
+			ffa_mem_desc_offset(buf, 0, hyp_ffa_version);
 	offset = ep_mem_access->composite_off;
 	/*
 	 * We can trust the SPMD to get this right, but let's at least
@@ -639,6 +642,132 @@ static bool do_ffa_features(struct arm_smccc_res *res,
 	return true;
 }
 
+static int hyp_ffa_post_init(void)
+{
+	size_t min_rxtx_sz;
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_smc(FFA_ID_GET, 0, 0, 0, 0, 0, 0, 0, &res);
+	if (res.a0 != FFA_SUCCESS)
+		return -EOPNOTSUPP;
+
+	if (res.a2 != HOST_FFA_ID)
+		return -EINVAL;
+
+	arm_smccc_1_1_smc(FFA_FEATURES, FFA_FN64_RXTX_MAP,
+			  0, 0, 0, 0, 0, 0, &res);
+	if (res.a0 != FFA_SUCCESS)
+		return -EOPNOTSUPP;
+
+	switch (res.a2) {
+	case FFA_FEAT_RXTX_MIN_SZ_4K:
+		min_rxtx_sz = SZ_4K;
+		break;
+	case FFA_FEAT_RXTX_MIN_SZ_16K:
+		min_rxtx_sz = SZ_16K;
+		break;
+	case FFA_FEAT_RXTX_MIN_SZ_64K:
+		min_rxtx_sz = SZ_64K;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (min_rxtx_sz > PAGE_SIZE)
+		return -EOPNOTSUPP;
+
+	return 0;
+}
+
+static void do_ffa_version(struct arm_smccc_res *res,
+			   struct kvm_cpu_context *ctxt)
+{
+	DECLARE_REG(u32, ffa_req_version, ctxt, 1);
+
+	if (FFA_MAJOR_VERSION(ffa_req_version) != 1) {
+		res->a0 = FFA_RET_NOT_SUPPORTED;
+		return;
+	}
+
+	hyp_spin_lock(&version_lock);
+	if (has_version_negotiated) {
+		res->a0 = hyp_ffa_version;
+		goto unlock;
+	}
+
+	/*
+	 * If the client driver tries to downgrade the version, we need to ask
+	 * first if TEE supports it.
+	 */
+	if (FFA_MINOR_VERSION(ffa_req_version) < FFA_MINOR_VERSION(hyp_ffa_version)) {
+		arm_smccc_1_1_smc(FFA_VERSION, ffa_req_version, 0,
+				  0, 0, 0, 0, 0,
+				  res);
+		if (res->a0 == FFA_RET_NOT_SUPPORTED)
+			goto unlock;
+
+		hyp_ffa_version = ffa_req_version;
+	}
+
+	if (hyp_ffa_post_init())
+		res->a0 = FFA_RET_NOT_SUPPORTED;
+	else {
+		has_version_negotiated = true;
+		res->a0 = hyp_ffa_version;
+	}
+unlock:
+	hyp_spin_unlock(&version_lock);
+}
+
+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, partition_sz, copy_sz;
+
+	hyp_spin_lock(&host_buffers.lock);
+	if (!host_buffers.rx) {
+		ffa_to_smccc_res(res, FFA_RET_BUSY);
+		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;
+
+	if (hyp_ffa_version > FFA_VERSION_1_0) {
+		/* Get the number of partitions deployed in the system */
+		if (flags & 0x1)
+			goto out_unlock;
+
+		partition_sz  = res->a3;
+	} else {
+		/* FFA_VERSION_1_0 lacks the size in the response */
+		partition_sz = FFA_1_0_PARTITON_INFO_SZ;
+	}
+
+	copy_sz = partition_sz * count;
+	if (copy_sz > KVM_FFA_MBOX_NR_PAGES * PAGE_SIZE) {
+		ffa_to_smccc_res(res, FFA_RET_ABORTED);
+		goto out_unlock;
+	}
+
+	memcpy(host_buffers.rx, hyp_buffers.rx, copy_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;
@@ -659,6 +788,11 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id)
 	if (!is_ffa_call(func_id))
 		return false;
 
+	if (!has_version_negotiated && func_id != FFA_VERSION) {
+		ffa_to_smccc_error(&res, FFA_RET_INVALID_PARAMETERS);
+		goto out_handled;
+	}
+
 	switch (func_id) {
 	case FFA_FEATURES:
 		if (!do_ffa_features(&res, host_ctxt))
@@ -685,6 +819,12 @@ 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_VERSION:
+		do_ffa_version(&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))
@@ -699,13 +839,12 @@ bool kvm_host_ffa_handler(struct kvm_cpu_context *host_ctxt, u32 func_id)
 int hyp_ffa_init(void *pages)
 {
 	struct arm_smccc_res res;
-	size_t min_rxtx_sz;
 	void *tx, *rx;
 
 	if (kvm_host_psci_config.smccc_version < ARM_SMCCC_VERSION_1_2)
 		return 0;
 
-	arm_smccc_1_1_smc(FFA_VERSION, FFA_VERSION_1_0, 0, 0, 0, 0, 0, 0, &res);
+	arm_smccc_1_1_smc(FFA_VERSION, FFA_VERSION_1_1, 0, 0, 0, 0, 0, 0, &res);
 	if (res.a0 == FFA_RET_NOT_SUPPORTED)
 		return 0;
 
@@ -725,34 +864,10 @@ int hyp_ffa_init(void *pages)
 	if (FFA_MAJOR_VERSION(res.a0) != 1)
 		return -EOPNOTSUPP;
 
-	arm_smccc_1_1_smc(FFA_ID_GET, 0, 0, 0, 0, 0, 0, 0, &res);
-	if (res.a0 != FFA_SUCCESS)
-		return -EOPNOTSUPP;
-
-	if (res.a2 != HOST_FFA_ID)
-		return -EINVAL;
-
-	arm_smccc_1_1_smc(FFA_FEATURES, FFA_FN64_RXTX_MAP,
-			  0, 0, 0, 0, 0, 0, &res);
-	if (res.a0 != FFA_SUCCESS)
-		return -EOPNOTSUPP;
-
-	switch (res.a2) {
-	case FFA_FEAT_RXTX_MIN_SZ_4K:
-		min_rxtx_sz = SZ_4K;
-		break;
-	case FFA_FEAT_RXTX_MIN_SZ_16K:
-		min_rxtx_sz = SZ_16K;
-		break;
-	case FFA_FEAT_RXTX_MIN_SZ_64K:
-		min_rxtx_sz = SZ_64K;
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	if (min_rxtx_sz > PAGE_SIZE)
-		return -EOPNOTSUPP;
+	if (FFA_MINOR_VERSION(res.a0) < FFA_MINOR_VERSION(FFA_VERSION_1_1))
+		hyp_ffa_version = res.a0;
+	else
+		hyp_ffa_version = FFA_VERSION_1_1;
 
 	tx = pages;
 	pages += KVM_FFA_MBOX_NR_PAGES * PAGE_SIZE;
@@ -775,5 +890,6 @@ int hyp_ffa_init(void *pages)
 		.lock	= __HYP_SPIN_LOCK_UNLOCKED,
 	};
 
+	version_lock = __HYP_SPIN_LOCK_UNLOCKED;
 	return 0;
 }

include/linux/arm_ffa.h

@@ -212,6 +212,9 @@ bool ffa_device_is_valid(struct ffa_device *ffa_dev) { return false; }
 
 extern const struct bus_type ffa_bus_type;
 
+/* The FF-A 1.0 partition structure lacks the uuid[4] */
+#define FFA_1_0_PARTITON_INFO_SZ	(8)
+
 /* FFA transport related */
 struct ffa_partition_info {
 	u16 id;