From 79e165b8ccc03db795e17054490743a96630fd02 Mon Sep 17 00:00:00 2001
From: Will Deacon <willdeacon@google.com>
Date: Thu, 7 Jul 2022 15:51:43 +0100
Subject: [PATCH] Revert "ANDROID: KVM: arm64: Implement hyp -> host memory
 donation"

This reverts commit 17086543c9cfbafa4ebf1c66cb140f9add7cc257.

Bug: 233587962
Signed-off-by: Will Deacon <willdeacon@google.com>
Change-Id: Ib5e25f606e69411178c933972266f278dbbef369
---
 arch/arm64/kvm/hyp/nvhe/mem_protect.c | 60 ---------------------------
 1 file changed, 60 deletions(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
index 8f0710d64572..ff9532cbe6ff 100644
--- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c
+++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
@@ -457,9 +457,6 @@ struct pkvm_mem_transition {
 				/* Address in the completer's address space */
 				u64	completer_addr;
 			} host;
-			struct {
-				u64	completer_addr;
-			} hyp;
 		};
 	} initiator;
 
@@ -599,30 +596,6 @@ static int host_initiate_donation(u64 *completer_addr,
 	return host_stage2_set_owner_locked(tx->initiator.addr, size, owner_id);
 }
 
-static bool __host_ack_skip_pgtable_check(const struct pkvm_mem_transition *tx)
-{
-	return !(IS_ENABLED(CONFIG_NVHE_EL2_DEBUG) ||
-		 tx->initiator.id != PKVM_ID_HYP);
-}
-
-static int host_ack_donation(u64 addr, const struct pkvm_mem_transition *tx)
-{
-	u64 size = tx->nr_pages * PAGE_SIZE;
-
-	if (__host_ack_skip_pgtable_check(tx))
-		return 0;
-
-	return __host_check_page_state_range(addr, size, PKVM_NOPAGE);
-}
-
-static int host_complete_donation(u64 addr, const struct pkvm_mem_transition *tx)
-{
-	u64 size = tx->nr_pages * PAGE_SIZE;
-	u8 host_id = completer_owner_id(tx);
-
-	return host_stage2_set_owner_locked(addr, size, host_id);
-}
-
 static enum pkvm_page_state hyp_get_page_state(kvm_pte_t pte)
 {
 	if (!kvm_pte_valid(pte))
@@ -643,27 +616,6 @@ static int __hyp_check_page_state_range(u64 addr, u64 size,
 	return check_page_state_range(&pkvm_pgtable, addr, size, &d);
 }
 
-static int hyp_request_donation(u64 *completer_addr,
-				const struct pkvm_mem_transition *tx)
-{
-	u64 size = tx->nr_pages * PAGE_SIZE;
-	u64 addr = tx->initiator.addr;
-
-	*completer_addr = tx->initiator.hyp.completer_addr;
-	return __hyp_check_page_state_range(addr, size, PKVM_PAGE_OWNED);
-}
-
-static int hyp_initiate_donation(u64 *completer_addr,
-				 const struct pkvm_mem_transition *tx)
-{
-	u64 size = tx->nr_pages * PAGE_SIZE;
-	int ret;
-
-	*completer_addr = tx->initiator.hyp.completer_addr;
-	ret = kvm_pgtable_hyp_unmap(&pkvm_pgtable, tx->initiator.addr, size);
-	return (ret != size) ? -EFAULT : 0;
-}
-
 static bool __hyp_ack_skip_pgtable_check(const struct pkvm_mem_transition *tx)
 {
 	return !(IS_ENABLED(CONFIG_NVHE_EL2_DEBUG) ||
@@ -894,9 +846,6 @@ static int check_donation(struct pkvm_mem_donation *donation)
 	case PKVM_ID_HOST:
 		ret = host_request_owned_transition(&completer_addr, tx);
 		break;
-	case PKVM_ID_HYP:
-		ret = hyp_request_donation(&completer_addr, tx);
-		break;
 	default:
 		ret = -EINVAL;
 	}
@@ -905,9 +854,6 @@ static int check_donation(struct pkvm_mem_donation *donation)
 		return ret;
 
 	switch (tx->completer.id){
-	case PKVM_ID_HOST:
-		ret = host_ack_donation(completer_addr, tx);
-		break;
 	case PKVM_ID_HYP:
 		ret = hyp_ack_donation(completer_addr, tx);
 		break;
@@ -928,9 +874,6 @@ static int __do_donate(struct pkvm_mem_donation *donation)
 	case PKVM_ID_HOST:
 		ret = host_initiate_donation(&completer_addr, tx);
 		break;
-	case PKVM_ID_HYP:
-		ret = hyp_initiate_donation(&completer_addr, tx);
-		break;
 	default:
 		ret = -EINVAL;
 	}
@@ -939,9 +882,6 @@ static int __do_donate(struct pkvm_mem_donation *donation)
 		return ret;
 
 	switch (tx->completer.id){
-	case PKVM_ID_HOST:
-		ret = host_complete_donation(completer_addr, tx);
-		break;
 	case PKVM_ID_HYP:
 		ret = hyp_complete_donation(completer_addr, tx);
 		break;