1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * KVM guest address space mapping code 4 * 5 * Copyright IBM Corp. 2007, 2016, 2025 6 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> 7 * Claudio Imbrenda <imbrenda@linux.ibm.com> 8 */ 9 10 #ifndef ARCH_KVM_S390_GMAP_H 11 #define ARCH_KVM_S390_GMAP_H 12 13 #include "dat.h" 14 15 /** 16 * enum gmap_flags - Flags of a gmap. 17 * 18 * @GMAP_FLAG_SHADOW: The gmap is a vsie shadow gmap. 19 * @GMAP_FLAG_OWNS_PAGETABLES: The gmap owns all dat levels; normally 1, is 0 20 * only for ucontrol per-cpu gmaps, since they 21 * share the page tables with the main gmap. 22 * @GMAP_FLAG_IS_UCONTROL: The gmap is ucontrol (main gmap or per-cpu gmap). 23 * @GMAP_FLAG_ALLOW_HPAGE_1M: 1M hugepages are allowed for this gmap, 24 * independently of the page size used by userspace. 25 * @GMAP_FLAG_ALLOW_HPAGE_2G: 2G hugepages are allowed for this gmap, 26 * independently of the page size used by userspace. 27 * @GMAP_FLAG_PFAULT_ENABLED: Pfault is enabled for the gmap. 28 * @GMAP_FLAG_USES_SKEYS: If the guest uses storage keys. 29 * @GMAP_FLAG_USES_CMM: Whether the guest uses CMMA. 30 * @GMAP_FLAG_EXPORT_ON_UNMAP: Whether to export guest pages when unmapping. 31 */ 32 enum gmap_flags { 33 GMAP_FLAG_SHADOW = 0, 34 GMAP_FLAG_OWNS_PAGETABLES, 35 GMAP_FLAG_IS_UCONTROL, 36 GMAP_FLAG_ALLOW_HPAGE_1M, 37 GMAP_FLAG_ALLOW_HPAGE_2G, 38 GMAP_FLAG_PFAULT_ENABLED, 39 GMAP_FLAG_USES_SKEYS, 40 GMAP_FLAG_USES_CMM, 41 GMAP_FLAG_EXPORT_ON_UNMAP, 42 }; 43 44 /** 45 * struct gmap_struct - Guest address space. 46 * 47 * @flags: GMAP_FLAG_* flags. 48 * @edat_level: The edat level of this shadow gmap. 49 * @kvm: The vm. 50 * @asce: The ASCE used by this gmap. 51 * @list: List head used in children gmaps for the children gmap list. 52 * @children_lock: Protects children and scb_users. 53 * @children: List of child gmaps of this gmap. 54 * @scb_users: List of vsie_scb that use this shadow gmap. 55 * @parent: Parent gmap of a child gmap. 56 * @guest_asce: Original ASCE of this shadow gmap. 57 * @host_to_rmap_lock: Protects host_to_rmap. 58 * @host_to_rmap: Radix tree mapping host addresses to guest addresses. 59 */ 60 struct gmap { 61 unsigned long flags; 62 unsigned char edat_level; 63 struct kvm *kvm; 64 union asce asce; 65 struct list_head list; 66 spinlock_t children_lock; /* Protects: children, scb_users */ 67 struct list_head children; 68 struct list_head scb_users; 69 struct gmap *parent; 70 union asce guest_asce; 71 spinlock_t host_to_rmap_lock; /* Protects host_to_rmap */ 72 struct radix_tree_root host_to_rmap; 73 refcount_t refcount; 74 }; 75 76 struct gmap_cache { 77 struct list_head list; 78 struct gmap *gmap; 79 }; 80 81 #define gmap_for_each_rmap_safe(pos, n, head) \ 82 for (pos = (head); n = pos ? pos->next : NULL, pos; pos = n) 83 84 int s390_replace_asce(struct gmap *gmap); 85 bool _gmap_unmap_prefix(struct gmap *gmap, gfn_t gfn, gfn_t end, bool hint); 86 bool gmap_age_gfn(struct gmap *gmap, gfn_t start, gfn_t end); 87 bool gmap_unmap_gfn_range(struct gmap *gmap, struct kvm_memory_slot *slot, gfn_t start, gfn_t end); 88 int gmap_try_fixup_minor(struct gmap *gmap, struct guest_fault *fault); 89 struct gmap *gmap_new(struct kvm *kvm, gfn_t limit); 90 struct gmap *gmap_new_child(struct gmap *parent, gfn_t limit); 91 void gmap_remove_child(struct gmap *child); 92 void gmap_dispose(struct gmap *gmap); 93 int gmap_link(struct kvm_s390_mmu_cache *mc, struct gmap *gmap, struct guest_fault *fault); 94 void gmap_sync_dirty_log(struct gmap *gmap, gfn_t start, gfn_t end); 95 int gmap_set_limit(struct gmap *gmap, gfn_t limit); 96 int gmap_ucas_translate(struct kvm_s390_mmu_cache *mc, struct gmap *gmap, gpa_t *gaddr); 97 int gmap_ucas_map(struct gmap *gmap, gfn_t p_gfn, gfn_t c_gfn, unsigned long count); 98 void gmap_ucas_unmap(struct gmap *gmap, gfn_t c_gfn, unsigned long count); 99 int gmap_enable_skeys(struct gmap *gmap); 100 int gmap_pv_destroy_range(struct gmap *gmap, gfn_t start, gfn_t end, bool interruptible); 101 int gmap_insert_rmap(struct gmap *sg, gfn_t p_gfn, gfn_t r_gfn, int level); 102 int gmap_protect_rmap(struct kvm_s390_mmu_cache *mc, struct gmap *sg, gfn_t p_gfn, gfn_t r_gfn, 103 kvm_pfn_t pfn, int level, bool wr); 104 void gmap_set_cmma_all_dirty(struct gmap *gmap); 105 void _gmap_handle_vsie_unshadow_event(struct gmap *parent, gfn_t gfn); 106 struct gmap *gmap_create_shadow(struct kvm_s390_mmu_cache *mc, struct gmap *gmap, 107 union asce asce, int edat_level); 108 void gmap_split_huge_pages(struct gmap *gmap); 109 110 static inline bool uses_skeys(struct gmap *gmap) 111 { 112 return test_bit(GMAP_FLAG_USES_SKEYS, &gmap->flags); 113 } 114 115 static inline bool uses_cmm(struct gmap *gmap) 116 { 117 return test_bit(GMAP_FLAG_USES_CMM, &gmap->flags); 118 } 119 120 static inline bool pfault_enabled(struct gmap *gmap) 121 { 122 return test_bit(GMAP_FLAG_PFAULT_ENABLED, &gmap->flags); 123 } 124 125 static inline bool is_ucontrol(struct gmap *gmap) 126 { 127 return test_bit(GMAP_FLAG_IS_UCONTROL, &gmap->flags); 128 } 129 130 static inline bool is_shadow(struct gmap *gmap) 131 { 132 return test_bit(GMAP_FLAG_SHADOW, &gmap->flags); 133 } 134 135 static inline bool owns_page_tables(struct gmap *gmap) 136 { 137 return test_bit(GMAP_FLAG_OWNS_PAGETABLES, &gmap->flags); 138 } 139 140 static inline struct gmap *gmap_put(struct gmap *gmap) 141 { 142 if (refcount_dec_and_test(&gmap->refcount)) 143 gmap_dispose(gmap); 144 return NULL; 145 } 146 147 static inline void gmap_get(struct gmap *gmap) 148 { 149 WARN_ON_ONCE(unlikely(!refcount_inc_not_zero(&gmap->refcount))); 150 } 151 152 static inline void gmap_handle_vsie_unshadow_event(struct gmap *parent, gfn_t gfn) 153 { 154 scoped_guard(spinlock, &parent->children_lock) 155 _gmap_handle_vsie_unshadow_event(parent, gfn); 156 } 157 158 static inline bool gmap_mkold_prefix(struct gmap *gmap, gfn_t gfn, gfn_t end) 159 { 160 return _gmap_unmap_prefix(gmap, gfn, end, true); 161 } 162 163 static inline bool gmap_unmap_prefix(struct gmap *gmap, gfn_t gfn, gfn_t end) 164 { 165 return _gmap_unmap_prefix(gmap, gfn, end, false); 166 } 167 168 static inline union pgste _gmap_ptep_xchg(struct gmap *gmap, union pte *ptep, union pte newpte, 169 union pgste pgste, gfn_t gfn, bool needs_lock) 170 { 171 lockdep_assert_held(&gmap->kvm->mmu_lock); 172 if (!needs_lock) 173 lockdep_assert_held(&gmap->children_lock); 174 else 175 lockdep_assert_not_held(&gmap->children_lock); 176 177 if (pgste.prefix_notif && (newpte.h.p || newpte.h.i)) { 178 pgste.prefix_notif = 0; 179 gmap_unmap_prefix(gmap, gfn, gfn + 1); 180 } 181 if (pgste.vsie_notif && (ptep->h.p != newpte.h.p || newpte.h.i)) { 182 pgste.vsie_notif = 0; 183 if (needs_lock) 184 gmap_handle_vsie_unshadow_event(gmap, gfn); 185 else 186 _gmap_handle_vsie_unshadow_event(gmap, gfn); 187 } 188 if (!ptep->s.d && newpte.s.d && !newpte.s.s) 189 SetPageDirty(pfn_to_page(newpte.h.pfra)); 190 return __dat_ptep_xchg(ptep, pgste, newpte, gfn, gmap->asce, uses_skeys(gmap)); 191 } 192 193 static inline union pgste gmap_ptep_xchg(struct gmap *gmap, union pte *ptep, union pte newpte, 194 union pgste pgste, gfn_t gfn) 195 { 196 return _gmap_ptep_xchg(gmap, ptep, newpte, pgste, gfn, true); 197 } 198 199 static inline bool __must_check _gmap_crstep_xchg_atomic(struct gmap *gmap, union crste *crstep, 200 union crste oldcrste, union crste newcrste, 201 gfn_t gfn, bool needs_lock) 202 { 203 unsigned long align = is_pmd(newcrste) ? _PAGE_ENTRIES : _PAGE_ENTRIES * _CRST_ENTRIES; 204 205 if (KVM_BUG_ON(crstep->h.tt != oldcrste.h.tt || newcrste.h.tt != oldcrste.h.tt, gmap->kvm)) 206 return true; 207 208 lockdep_assert_held(&gmap->kvm->mmu_lock); 209 if (!needs_lock) 210 lockdep_assert_held(&gmap->children_lock); 211 212 gfn = ALIGN_DOWN(gfn, align); 213 if (crste_prefix(oldcrste) && (newcrste.h.p || newcrste.h.i || !crste_prefix(newcrste))) { 214 newcrste.s.fc1.prefix_notif = 0; 215 gmap_unmap_prefix(gmap, gfn, gfn + align); 216 } 217 if (crste_leaf(oldcrste) && oldcrste.s.fc1.vsie_notif && 218 (newcrste.h.p || newcrste.h.i || !newcrste.s.fc1.vsie_notif)) { 219 newcrste.s.fc1.vsie_notif = 0; 220 if (needs_lock) 221 gmap_handle_vsie_unshadow_event(gmap, gfn); 222 else 223 _gmap_handle_vsie_unshadow_event(gmap, gfn); 224 } 225 if (!oldcrste.s.fc1.d && newcrste.s.fc1.d && !newcrste.s.fc1.s) 226 SetPageDirty(phys_to_page(crste_origin_large(newcrste))); 227 return dat_crstep_xchg_atomic(crstep, oldcrste, newcrste, gfn, gmap->asce); 228 } 229 230 static inline bool __must_check gmap_crstep_xchg_atomic(struct gmap *gmap, union crste *crstep, 231 union crste oldcrste, union crste newcrste, 232 gfn_t gfn) 233 { 234 return _gmap_crstep_xchg_atomic(gmap, crstep, oldcrste, newcrste, gfn, true); 235 } 236 237 /** 238 * gmap_is_shadow_valid() - check if a shadow guest address space matches the 239 * given properties and is still valid. 240 * @sg: Pointer to the shadow guest address space structure. 241 * @asce: ASCE for which the shadow table is requested. 242 * @edat_level: Edat level to be used for the shadow translation. 243 * 244 * Return: true if the gmap shadow is still valid and matches the given 245 * properties and the caller can continue using it; false otherwise, the 246 * caller has to request a new shadow gmap in this case. 247 */ 248 static inline bool gmap_is_shadow_valid(struct gmap *sg, union asce asce, int edat_level) 249 { 250 return sg->guest_asce.val == asce.val && sg->edat_level == edat_level; 251 } 252 253 #endif /* ARCH_KVM_S390_GMAP_H */ 254