Commit ba5b2e5b authored by Quentin Perret's avatar Quentin Perret Committed by Marc Zyngier
Browse files

KVM: arm64: Introduce {get,set}_host_state() helpers 



Instead of directly accessing the host_state member in struct hyp_page,
introduce static inline accessors to do it. The future hyp_state member
will follow the same pattern as it will need some logic in the accessors.

Reviewed-by: default avatarMarc Zyngier <maz@kernel.org>
Signed-off-by: default avatarQuentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20250416152648.2982950-5-qperret@google.com


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent cd4b0391

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

+11 −1
Original line number Diff line number Diff line
@@ -52,7 +52,7 @@ struct hyp_page { 
	u8 order;



	/* Host state. Guarded by the host stage-2 lock. */

	enum pkvm_page_state host_state : 8;

	unsigned __host_state : 8;



	u32 host_share_guest_count;

};
@@ -89,6 +89,16 @@ static inline struct hyp_page *hyp_phys_to_page(phys_addr_t phys) 
#define hyp_page_to_virt(page)	__hyp_va(hyp_page_to_phys(page))

#define hyp_page_to_pool(page)	(((struct hyp_page *)page)->pool)



static inline enum pkvm_page_state get_host_state(phys_addr_t phys)

{

	return (enum pkvm_page_state)hyp_phys_to_page(phys)->__host_state;

}



static inline void set_host_state(phys_addr_t phys, enum pkvm_page_state state)

{

	hyp_phys_to_page(phys)->__host_state = state;

}



/*

 * Refcounting for 'struct hyp_page'.

 * hyp_pool::lock must be held if atomic access to the refcount is required.

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

+7 −7
Original line number Diff line number Diff line
@@ -467,7 +467,7 @@ static int host_stage2_adjust_range(u64 addr, struct kvm_mem_range *range) 
		return -EAGAIN;



	if (pte) {

		WARN_ON(addr_is_memory(addr) && hyp_phys_to_page(addr)->host_state != PKVM_NOPAGE);

		WARN_ON(addr_is_memory(addr) && get_host_state(addr) != PKVM_NOPAGE);

		return -EPERM;

	}
@@ -496,7 +496,7 @@ static void __host_update_page_state(phys_addr_t addr, u64 size, enum pkvm_page_ 
	phys_addr_t end = addr + size;



	for (; addr < end; addr += PAGE_SIZE)

		hyp_phys_to_page(addr)->host_state = state;

		set_host_state(addr, state);

}



int host_stage2_set_owner_locked(phys_addr_t addr, u64 size, u8 owner_id)
@@ -627,7 +627,7 @@ static int __host_check_page_state_range(u64 addr, u64 size, 


	hyp_assert_lock_held(&host_mmu.lock);

	for (; addr < end; addr += PAGE_SIZE) {

		if (hyp_phys_to_page(addr)->host_state != state)

		if (get_host_state(addr) != state)

			return -EPERM;

	}
@@ -637,7 +637,7 @@ static int __host_check_page_state_range(u64 addr, u64 size, 
static int __host_set_page_state_range(u64 addr, u64 size,

				       enum pkvm_page_state state)

{

	if (hyp_phys_to_page(addr)->host_state == PKVM_NOPAGE) {

	if (get_host_state(addr) == PKVM_NOPAGE) {

		int ret = host_stage2_idmap_locked(addr, size, PKVM_HOST_MEM_PROT);



		if (ret)
@@ -911,7 +911,7 @@ int __pkvm_host_share_guest(u64 pfn, u64 gfn, struct pkvm_hyp_vcpu *vcpu, 
		goto unlock;



	page = hyp_phys_to_page(phys);

	switch (page->host_state) {

	switch (get_host_state(phys)) {

	case PKVM_PAGE_OWNED:

		WARN_ON(__host_set_page_state_range(phys, PAGE_SIZE, PKVM_PAGE_SHARED_OWNED));

		break;
@@ -964,9 +964,9 @@ static int __check_host_shared_guest(struct pkvm_hyp_vm *vm, u64 *__phys, u64 ip 
	if (WARN_ON(ret))

		return ret;



	page = hyp_phys_to_page(phys);

	if (page->host_state != PKVM_PAGE_SHARED_OWNED)

	if (get_host_state(phys) != PKVM_PAGE_SHARED_OWNED)

		return -EPERM;

	page = hyp_phys_to_page(phys);

	if (WARN_ON(!page->host_share_guest_count))

		return -EINVAL;

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

+2 −2
Original line number Diff line number Diff line
@@ -201,10 +201,10 @@ static int fix_host_ownership_walker(const struct kvm_pgtable_visit_ctx *ctx, 
	case PKVM_PAGE_OWNED:

		return host_stage2_set_owner_locked(phys, PAGE_SIZE, PKVM_ID_HYP);

	case PKVM_PAGE_SHARED_OWNED:

		hyp_phys_to_page(phys)->host_state = PKVM_PAGE_SHARED_BORROWED;

		set_host_state(phys, PKVM_PAGE_SHARED_BORROWED);

		break;

	case PKVM_PAGE_SHARED_BORROWED:

		hyp_phys_to_page(phys)->host_state = PKVM_PAGE_SHARED_OWNED;

		set_host_state(phys, PKVM_PAGE_SHARED_OWNED);

		break;

	default:

		return -EINVAL;