[PATCH 1/3] KVM: arm64: Drop pkvm_mem_transition for FF-A

From: Quentin Perret
Date: Fri Jan 10 2025 - 07:20:03 EST


Simplify the __pkvm_host_{un}share_ffa() paths by using
{check,set}_page_state_range().

No functional changes intended.

Signed-off-by: Quentin Perret <qperret@xxxxxxxxxx>
---
arch/arm64/kvm/hyp/nvhe/mem_protect.c | 36 ++++++++-------------------
1 file changed, 10 insertions(+), 26 deletions(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
index 392f036bc69e..3a3d9fcbc508 100644
--- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c
+++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
@@ -1324,22 +1324,14 @@ void hyp_unpin_shared_mem(void *from, void *to)

int __pkvm_host_share_ffa(u64 pfn, u64 nr_pages)
{
+ u64 phys = hyp_pfn_to_phys(pfn);
+ u64 size = PAGE_SIZE * nr_pages;
int ret;
- struct pkvm_mem_share share = {
- .tx = {
- .nr_pages = nr_pages,
- .initiator = {
- .id = PKVM_ID_HOST,
- .addr = hyp_pfn_to_phys(pfn),
- },
- .completer = {
- .id = PKVM_ID_FFA,
- },
- },
- };

host_lock_component();
- ret = do_share(&share);
+ ret = __host_check_page_state_range(phys, size, PKVM_PAGE_OWNED);
+ if (!ret)
+ ret = __host_set_page_state_range(phys, size, PKVM_PAGE_SHARED_OWNED);
host_unlock_component();

return ret;
@@ -1347,22 +1339,14 @@ int __pkvm_host_share_ffa(u64 pfn, u64 nr_pages)

int __pkvm_host_unshare_ffa(u64 pfn, u64 nr_pages)
{
+ u64 phys = hyp_pfn_to_phys(pfn);
+ u64 size = PAGE_SIZE * nr_pages;
int ret;
- struct pkvm_mem_share share = {
- .tx = {
- .nr_pages = nr_pages,
- .initiator = {
- .id = PKVM_ID_HOST,
- .addr = hyp_pfn_to_phys(pfn),
- },
- .completer = {
- .id = PKVM_ID_FFA,
- },
- },
- };

host_lock_component();
- ret = do_unshare(&share);
+ ret = __host_check_page_state_range(phys, size, PKVM_PAGE_SHARED_OWNED);
+ if (!ret)
+ ret = __host_set_page_state_range(phys, size, PKVM_PAGE_OWNED);
host_unlock_component();

return ret;
--
2.47.1.688.g23fc6f90ad-goog