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 bool invalidated; 64 struct kvm *kvm; 65 union asce asce; 66 struct list_head list; 67 spinlock_t children_lock; /* Protects: children, scb_users */ 68 struct list_head children; 69 struct list_head scb_users; 70 struct gmap *parent; 71 union asce guest_asce; 72 spinlock_t host_to_rmap_lock; /* Protects host_to_rmap */ 73 struct radix_tree_root host_to_rmap; 74 refcount_t refcount; 75 }; 76 77 struct gmap_cache { 78 struct list_head list; 79 struct gmap *gmap; 80 }; 81 82 #define gmap_for_each_rmap_safe(pos, n, head) \ 83 for (pos = (head); n = pos ? pos->next : NULL, pos; pos = n) 84 85 int s390_replace_asce(struct gmap *gmap); 86 bool _gmap_unmap_prefix(struct gmap *gmap, gfn_t gfn, gfn_t end, bool hint); 87 bool gmap_age_gfn(struct gmap *gmap, gfn_t start, gfn_t end); 88 bool gmap_unmap_gfn_range(struct gmap *gmap, struct kvm_memory_slot *slot, gfn_t start, gfn_t end); 89 int gmap_try_fixup_minor(struct gmap *gmap, struct guest_fault *fault); 90 struct gmap *gmap_new(struct kvm *kvm, gfn_t limit); 91 struct gmap *gmap_new_child(struct gmap *parent, gfn_t limit); 92 void gmap_remove_child(struct gmap *child); 93 void gmap_dispose(struct gmap *gmap); 94 int gmap_link(struct kvm_s390_mmu_cache *mc, struct gmap *gmap, struct guest_fault *fault, 95 struct kvm_memory_slot *slot); 96 void gmap_sync_dirty_log(struct gmap *gmap, gfn_t start, gfn_t end); 97 int gmap_set_limit(struct gmap *gmap, gfn_t limit); 98 int gmap_ucas_translate(struct kvm_s390_mmu_cache *mc, struct gmap *gmap, gpa_t *gaddr); 99 int gmap_ucas_map(struct gmap *gmap, gfn_t p_gfn, gfn_t c_gfn, unsigned long count); 100 void gmap_ucas_unmap(struct gmap *gmap, gfn_t c_gfn, unsigned long count); 101 int gmap_enable_skeys(struct gmap *gmap); 102 int gmap_pv_destroy_range(struct gmap *gmap, gfn_t start, gfn_t end, bool interruptible); 103 int gmap_insert_rmap(struct gmap *sg, gfn_t p_gfn, gfn_t r_gfn, int level); 104 int gmap_protect_rmap(struct kvm_s390_mmu_cache *mc, struct gmap *sg, gfn_t p_gfn, gfn_t r_gfn, 105 kvm_pfn_t pfn, int level, bool wr); 106 void gmap_set_cmma_all_dirty(struct gmap *gmap); 107 void _gmap_handle_vsie_unshadow_event(struct gmap *parent, gfn_t gfn); 108 struct gmap *gmap_create_shadow(struct kvm_s390_mmu_cache *mc, struct gmap *gmap, 109 union asce asce, int edat_level); 110 void gmap_split_huge_pages(struct gmap *gmap); 111 112 static inline bool uses_skeys(struct gmap *gmap) 113 { 114 return test_bit(GMAP_FLAG_USES_SKEYS, &gmap->flags); 115 } 116 117 static inline bool uses_cmm(struct gmap *gmap) 118 { 119 return test_bit(GMAP_FLAG_USES_CMM, &gmap->flags); 120 } 121 122 static inline bool pfault_enabled(struct gmap *gmap) 123 { 124 return test_bit(GMAP_FLAG_PFAULT_ENABLED, &gmap->flags); 125 } 126 127 static inline bool is_ucontrol(struct gmap *gmap) 128 { 129 return test_bit(GMAP_FLAG_IS_UCONTROL, &gmap->flags); 130 } 131 132 static inline bool is_shadow(struct gmap *gmap) 133 { 134 return test_bit(GMAP_FLAG_SHADOW, &gmap->flags); 135 } 136 137 static inline bool owns_page_tables(struct gmap *gmap) 138 { 139 return test_bit(GMAP_FLAG_OWNS_PAGETABLES, &gmap->flags); 140 } 141 142 static inline struct gmap *gmap_put(struct gmap *gmap) 143 { 144 if (refcount_dec_and_test(&gmap->refcount)) 145 gmap_dispose(gmap); 146 return NULL; 147 } 148 149 static inline void gmap_get(struct gmap *gmap) 150 { 151 WARN_ON_ONCE(unlikely(!refcount_inc_not_zero(&gmap->refcount))); 152 } 153 154 static inline void gmap_handle_vsie_unshadow_event(struct gmap *parent, gfn_t gfn) 155 { 156 scoped_guard(spinlock, &parent->children_lock) 157 _gmap_handle_vsie_unshadow_event(parent, gfn); 158 } 159 160 static inline bool gmap_mkold_prefix(struct gmap *gmap, gfn_t gfn, gfn_t end) 161 { 162 return _gmap_unmap_prefix(gmap, gfn, end, true); 163 } 164 165 static inline bool gmap_unmap_prefix(struct gmap *gmap, gfn_t gfn, gfn_t end) 166 { 167 return _gmap_unmap_prefix(gmap, gfn, end, false); 168 } 169 170 static inline union pgste _gmap_ptep_xchg(struct gmap *gmap, union pte *ptep, union pte newpte, 171 union pgste pgste, gfn_t gfn, bool needs_lock) 172 { 173 lockdep_assert_held(&gmap->kvm->mmu_lock); 174 if (!needs_lock) 175 lockdep_assert_held(&gmap->children_lock); 176 else 177 lockdep_assert_not_held(&gmap->children_lock); 178 179 if (pgste.prefix_notif && (newpte.h.p || newpte.h.i)) { 180 pgste.prefix_notif = 0; 181 gmap_unmap_prefix(gmap, gfn, gfn + 1); 182 } 183 if (pgste.vsie_notif && (ptep->h.p != newpte.h.p || newpte.h.i)) { 184 pgste.vsie_notif = 0; 185 if (needs_lock) 186 gmap_handle_vsie_unshadow_event(gmap, gfn); 187 else 188 _gmap_handle_vsie_unshadow_event(gmap, gfn); 189 } 190 if (!ptep->s.d && newpte.s.d && !newpte.s.s) 191 SetPageDirty(pfn_to_page(newpte.h.pfra)); 192 return __dat_ptep_xchg(ptep, pgste, newpte, gfn, gmap->asce, uses_skeys(gmap)); 193 } 194 195 static inline union pgste gmap_ptep_xchg(struct gmap *gmap, union pte *ptep, union pte newpte, 196 union pgste pgste, gfn_t gfn) 197 { 198 return _gmap_ptep_xchg(gmap, ptep, newpte, pgste, gfn, true); 199 } 200 201 static inline bool __must_check _gmap_crstep_xchg_atomic(struct gmap *gmap, union crste *crstep, 202 union crste oldcrste, union crste newcrste, 203 gfn_t gfn, bool needs_lock) 204 { 205 unsigned long align = is_pmd(newcrste) ? _PAGE_ENTRIES : _PAGE_ENTRIES * _CRST_ENTRIES; 206 207 if (KVM_BUG_ON(crstep->h.tt != oldcrste.h.tt || newcrste.h.tt != oldcrste.h.tt, gmap->kvm)) 208 return true; 209 210 lockdep_assert_held(&gmap->kvm->mmu_lock); 211 if (!needs_lock) 212 lockdep_assert_held(&gmap->children_lock); 213 214 gfn = ALIGN_DOWN(gfn, align); 215 if (crste_prefix(oldcrste) && (newcrste.h.p || newcrste.h.i || !crste_prefix(newcrste))) { 216 newcrste.s.fc1.prefix_notif = 0; 217 gmap_unmap_prefix(gmap, gfn, gfn + align); 218 } 219 if (crste_leaf(oldcrste) && oldcrste.s.fc1.vsie_notif && 220 (newcrste.h.p || newcrste.h.i || !newcrste.s.fc1.vsie_notif)) { 221 newcrste.s.fc1.vsie_notif = 0; 222 if (needs_lock) 223 gmap_handle_vsie_unshadow_event(gmap, gfn); 224 else 225 _gmap_handle_vsie_unshadow_event(gmap, gfn); 226 } 227 if (!oldcrste.s.fc1.d && newcrste.s.fc1.d && !newcrste.s.fc1.s) 228 SetPageDirty(phys_to_page(crste_origin_large(newcrste))); 229 return dat_crstep_xchg_atomic(crstep, oldcrste, newcrste, gfn, gmap->asce); 230 } 231 232 static inline bool __must_check gmap_crstep_xchg_atomic(struct gmap *gmap, union crste *crstep, 233 union crste oldcrste, union crste newcrste, 234 gfn_t gfn) 235 { 236 return _gmap_crstep_xchg_atomic(gmap, crstep, oldcrste, newcrste, gfn, true); 237 } 238 239 /** 240 * gmap_is_shadow_valid() - check if a shadow guest address space matches the 241 * given properties and is still valid. 242 * @sg: Pointer to the shadow guest address space structure. 243 * @asce: ASCE for which the shadow table is requested. 244 * @edat_level: Edat level to be used for the shadow translation. 245 * 246 * Return: true if the gmap shadow is still valid and matches the given 247 * properties and the caller can continue using it; false otherwise, the 248 * caller has to request a new shadow gmap in this case. 249 */ 250 static inline bool gmap_is_shadow_valid(struct gmap *sg, union asce asce, int edat_level) 251 { 252 return sg->guest_asce.val == asce.val && sg->edat_level == edat_level; 253 } 254 255 #endif /* ARCH_KVM_S390_GMAP_H */ 256