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

Source file repositories/reference/linux-study-clean/arch/arm64/kvm/hyp/include/nvhe/memory.h

File Facts

System
Linux kernel
Corpus path
arch/arm64/kvm/hyp/include/nvhe/memory.h
Extension
.h
Size
4419 bytes
Lines
160
Domain
Architecture Layer
Bucket
arch/arm64
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct hyp_page {
	u16 refcount;
	u8 order;

	/* Host state. Guarded by the host stage-2 lock. */
	unsigned __host_state : 4;

	/*
	 * Complement of the hyp state. Guarded by the hyp stage-1 lock. We use
	 * the complement so that the initial 0 in __hyp_state_comp (due to the
	 * entire vmemmap starting off zeroed) encodes PKVM_NOPAGE.
	 */
	unsigned __hyp_state_comp : 4;

	u32 host_share_guest_count;
};

extern u64 __hyp_vmemmap;
#define hyp_vmemmap ((struct hyp_page *)__hyp_vmemmap)

#define __hyp_va(phys)	((void *)((phys_addr_t)(phys) - hyp_physvirt_offset))

static inline void *hyp_phys_to_virt(phys_addr_t phys)
{
	return __hyp_va(phys);
}

static inline phys_addr_t hyp_virt_to_phys(void *addr)
{
	return __hyp_pa(addr);
}

#define hyp_phys_to_pfn(phys)	((phys) >> PAGE_SHIFT)
#define hyp_pfn_to_phys(pfn)	((phys_addr_t)((pfn) << PAGE_SHIFT))

static inline struct hyp_page *hyp_phys_to_page(phys_addr_t phys)
{
	BUILD_BUG_ON(sizeof(struct hyp_page) != sizeof(u64));
	return &hyp_vmemmap[hyp_phys_to_pfn(phys)];
}

#define hyp_virt_to_page(virt)	hyp_phys_to_page(__hyp_pa(virt))
#define hyp_virt_to_pfn(virt)	hyp_phys_to_pfn(__hyp_pa(virt))

#define hyp_page_to_pfn(page)	((struct hyp_page *)(page) - hyp_vmemmap)
#define hyp_page_to_phys(page)  hyp_pfn_to_phys((hyp_page_to_pfn(page)))
#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(struct hyp_page *p)
{
	return p->__host_state;
}

static inline void set_host_state(struct hyp_page *p, enum pkvm_page_state state)
{
	p->__host_state = state;
}

static inline enum pkvm_page_state get_hyp_state(struct hyp_page *p)
{
	return p->__hyp_state_comp ^ PKVM_PAGE_STATE_VMEMMAP_MASK;
}

static inline void set_hyp_state(struct hyp_page *p, enum pkvm_page_state state)
{
	p->__hyp_state_comp = state ^ PKVM_PAGE_STATE_VMEMMAP_MASK;
}

/*
 * Refcounting for 'struct hyp_page'.
 * hyp_pool::lock must be held if atomic access to the refcount is required.
 */
static inline int hyp_page_count(void *addr)
{
	struct hyp_page *p = hyp_virt_to_page(addr);

	return p->refcount;
}

static inline void hyp_page_ref_inc(struct hyp_page *p)
{
	BUG_ON(p->refcount == USHRT_MAX);
	p->refcount++;
}

static inline void hyp_page_ref_dec(struct hyp_page *p)
{
	BUG_ON(!p->refcount);
	p->refcount--;

Annotation

Implementation Notes