1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 #ifndef __KVM_HYP_MEMORY_H 3 #define __KVM_HYP_MEMORY_H 4 5 #include <asm/kvm_mmu.h> 6 #include <asm/page.h> 7 8 #include <linux/types.h> 9 10 /* 11 * Bits 0-1 are reserved to track the memory ownership state of each page: 12 * 00: The page is owned exclusively by the page-table owner. 13 * 01: The page is owned by the page-table owner, but is shared 14 * with another entity. 15 * 10: The page is shared with, but not owned by the page-table owner. 16 * 11: Reserved for future use (lending). 17 */ 18 enum pkvm_page_state { 19 PKVM_PAGE_OWNED = 0ULL, 20 PKVM_PAGE_SHARED_OWNED = BIT(0), 21 PKVM_PAGE_SHARED_BORROWED = BIT(1), 22 __PKVM_PAGE_RESERVED = BIT(0) | BIT(1), 23 24 /* Meta-states which aren't encoded directly in the PTE's SW bits */ 25 PKVM_NOPAGE = BIT(2), 26 }; 27 #define PKVM_PAGE_META_STATES_MASK (~__PKVM_PAGE_RESERVED) 28 29 #define PKVM_PAGE_STATE_PROT_MASK (KVM_PGTABLE_PROT_SW0 | KVM_PGTABLE_PROT_SW1) 30 static inline enum kvm_pgtable_prot pkvm_mkstate(enum kvm_pgtable_prot prot, 31 enum pkvm_page_state state) 32 { 33 prot &= ~PKVM_PAGE_STATE_PROT_MASK; 34 prot |= FIELD_PREP(PKVM_PAGE_STATE_PROT_MASK, state); 35 return prot; 36 } 37 38 static inline enum pkvm_page_state pkvm_getstate(enum kvm_pgtable_prot prot) 39 { 40 return FIELD_GET(PKVM_PAGE_STATE_PROT_MASK, prot); 41 } 42 43 struct hyp_page { 44 u16 refcount; 45 u8 order; 46 47 /* Host (non-meta) state. Guarded by the host stage-2 lock. */ 48 enum pkvm_page_state host_state : 8; 49 50 u32 host_share_guest_count; 51 }; 52 53 extern u64 __hyp_vmemmap; 54 #define hyp_vmemmap ((struct hyp_page *)__hyp_vmemmap) 55 56 #define __hyp_va(phys) ((void *)((phys_addr_t)(phys) - hyp_physvirt_offset)) 57 58 static inline void *hyp_phys_to_virt(phys_addr_t phys) 59 { 60 return __hyp_va(phys); 61 } 62 63 static inline phys_addr_t hyp_virt_to_phys(void *addr) 64 { 65 return __hyp_pa(addr); 66 } 67 68 #define hyp_phys_to_pfn(phys) ((phys) >> PAGE_SHIFT) 69 #define hyp_pfn_to_phys(pfn) ((phys_addr_t)((pfn) << PAGE_SHIFT)) 70 71 static inline struct hyp_page *hyp_phys_to_page(phys_addr_t phys) 72 { 73 BUILD_BUG_ON(sizeof(struct hyp_page) != sizeof(u64)); 74 return &hyp_vmemmap[hyp_phys_to_pfn(phys)]; 75 } 76 77 #define hyp_virt_to_page(virt) hyp_phys_to_page(__hyp_pa(virt)) 78 #define hyp_virt_to_pfn(virt) hyp_phys_to_pfn(__hyp_pa(virt)) 79 80 #define hyp_page_to_pfn(page) ((struct hyp_page *)(page) - hyp_vmemmap) 81 #define hyp_page_to_phys(page) hyp_pfn_to_phys((hyp_page_to_pfn(page))) 82 #define hyp_page_to_virt(page) __hyp_va(hyp_page_to_phys(page)) 83 #define hyp_page_to_pool(page) (((struct hyp_page *)page)->pool) 84 85 /* 86 * Refcounting for 'struct hyp_page'. 87 * hyp_pool::lock must be held if atomic access to the refcount is required. 88 */ 89 static inline int hyp_page_count(void *addr) 90 { 91 struct hyp_page *p = hyp_virt_to_page(addr); 92 93 return p->refcount; 94 } 95 96 static inline void hyp_page_ref_inc(struct hyp_page *p) 97 { 98 BUG_ON(p->refcount == USHRT_MAX); 99 p->refcount++; 100 } 101 102 static inline void hyp_page_ref_dec(struct hyp_page *p) 103 { 104 BUG_ON(!p->refcount); 105 p->refcount--; 106 } 107 108 static inline int hyp_page_ref_dec_and_test(struct hyp_page *p) 109 { 110 hyp_page_ref_dec(p); 111 return (p->refcount == 0); 112 } 113 114 static inline void hyp_set_page_refcounted(struct hyp_page *p) 115 { 116 BUG_ON(p->refcount); 117 p->refcount = 1; 118 } 119 #endif /* __KVM_HYP_MEMORY_H */ 120