1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * KVM guest address space mapping code 4 * 5 * Copyright IBM Corp. 2007, 2016 6 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> 7 */ 8 9 #ifndef _ASM_S390_GMAP_H 10 #define _ASM_S390_GMAP_H 11 12 #include <linux/radix-tree.h> 13 #include <linux/refcount.h> 14 15 /* Generic bits for GMAP notification on DAT table entry changes. */ 16 #define GMAP_NOTIFY_SHADOW 0x2 17 #define GMAP_NOTIFY_MPROT 0x1 18 19 /* Status bits only for huge segment entries */ 20 #define _SEGMENT_ENTRY_GMAP_IN 0x0800 /* invalidation notify bit */ 21 #define _SEGMENT_ENTRY_GMAP_UC 0x0002 /* dirty (migration) */ 22 23 /** 24 * struct gmap_struct - guest address space 25 * @list: list head for the mm->context gmap list 26 * @mm: pointer to the parent mm_struct 27 * @guest_to_host: radix tree with guest to host address translation 28 * @host_to_guest: radix tree with pointer to segment table entries 29 * @guest_table_lock: spinlock to protect all entries in the guest page table 30 * @ref_count: reference counter for the gmap structure 31 * @table: pointer to the page directory 32 * @asce: address space control element for gmap page table 33 * @pfault_enabled: defines if pfaults are applicable for the guest 34 * @guest_handle: protected virtual machine handle for the ultravisor 35 * @host_to_rmap: radix tree with gmap_rmap lists 36 * @children: list of shadow gmap structures 37 * @shadow_lock: spinlock to protect the shadow gmap list 38 * @parent: pointer to the parent gmap for shadow guest address spaces 39 * @orig_asce: ASCE for which the shadow page table has been created 40 * @edat_level: edat level to be used for the shadow translation 41 * @removed: flag to indicate if a shadow guest address space has been removed 42 * @initialized: flag to indicate if a shadow guest address space can be used 43 */ 44 struct gmap { 45 struct list_head list; 46 struct mm_struct *mm; 47 struct radix_tree_root guest_to_host; 48 struct radix_tree_root host_to_guest; 49 spinlock_t guest_table_lock; 50 refcount_t ref_count; 51 unsigned long *table; 52 unsigned long asce; 53 unsigned long asce_end; 54 void *private; 55 bool pfault_enabled; 56 /* only set for protected virtual machines */ 57 unsigned long guest_handle; 58 /* Additional data for shadow guest address spaces */ 59 struct radix_tree_root host_to_rmap; 60 struct list_head children; 61 spinlock_t shadow_lock; 62 struct gmap *parent; 63 unsigned long orig_asce; 64 int edat_level; 65 bool removed; 66 bool initialized; 67 }; 68 69 /** 70 * struct gmap_rmap - reverse mapping for shadow page table entries 71 * @next: pointer to next rmap in the list 72 * @raddr: virtual rmap address in the shadow guest address space 73 */ 74 struct gmap_rmap { 75 struct gmap_rmap *next; 76 unsigned long raddr; 77 }; 78 79 #define gmap_for_each_rmap(pos, head) \ 80 for (pos = (head); pos; pos = pos->next) 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 /** 86 * struct gmap_notifier - notify function block for page invalidation 87 * @notifier_call: address of callback function 88 */ 89 struct gmap_notifier { 90 struct list_head list; 91 struct rcu_head rcu; 92 void (*notifier_call)(struct gmap *gmap, unsigned long start, 93 unsigned long end); 94 }; 95 96 static inline int gmap_is_shadow(struct gmap *gmap) 97 { 98 return !!gmap->parent; 99 } 100 101 struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit); 102 void gmap_remove(struct gmap *gmap); 103 struct gmap *gmap_get(struct gmap *gmap); 104 void gmap_put(struct gmap *gmap); 105 void gmap_free(struct gmap *gmap); 106 struct gmap *gmap_alloc(unsigned long limit); 107 108 int gmap_map_segment(struct gmap *gmap, unsigned long from, 109 unsigned long to, unsigned long len); 110 int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len); 111 unsigned long __gmap_translate(struct gmap *, unsigned long gaddr); 112 int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr); 113 void gmap_discard(struct gmap *, unsigned long from, unsigned long to); 114 void __gmap_zap(struct gmap *, unsigned long gaddr); 115 void gmap_unlink(struct mm_struct *, unsigned long *table, unsigned long vmaddr); 116 117 int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val); 118 119 void gmap_unshadow(struct gmap *sg); 120 int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t, 121 int fake); 122 int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t, 123 int fake); 124 int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt, 125 int fake); 126 int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt, 127 int fake); 128 int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte); 129 130 void gmap_register_pte_notifier(struct gmap_notifier *); 131 void gmap_unregister_pte_notifier(struct gmap_notifier *); 132 133 int gmap_protect_one(struct gmap *gmap, unsigned long gaddr, int prot, unsigned long bits); 134 135 void gmap_sync_dirty_log_pmd(struct gmap *gmap, unsigned long dirty_bitmap[4], 136 unsigned long gaddr, unsigned long vmaddr); 137 int s390_disable_cow_sharing(void); 138 int s390_replace_asce(struct gmap *gmap); 139 void s390_uv_destroy_pfns(unsigned long count, unsigned long *pfns); 140 int __s390_uv_destroy_range(struct mm_struct *mm, unsigned long start, 141 unsigned long end, bool interruptible); 142 int kvm_s390_wiggle_split_folio(struct mm_struct *mm, struct folio *folio, bool split); 143 unsigned long *gmap_table_walk(struct gmap *gmap, unsigned long gaddr, int level); 144 145 /** 146 * s390_uv_destroy_range - Destroy a range of pages in the given mm. 147 * @mm: the mm on which to operate on 148 * @start: the start of the range 149 * @end: the end of the range 150 * 151 * This function will call cond_sched, so it should not generate stalls, but 152 * it will otherwise only return when it completed. 153 */ 154 static inline void s390_uv_destroy_range(struct mm_struct *mm, unsigned long start, 155 unsigned long end) 156 { 157 (void)__s390_uv_destroy_range(mm, start, end, false); 158 } 159 160 /** 161 * s390_uv_destroy_range_interruptible - Destroy a range of pages in the 162 * given mm, but stop when a fatal signal is received. 163 * @mm: the mm on which to operate on 164 * @start: the start of the range 165 * @end: the end of the range 166 * 167 * This function will call cond_sched, so it should not generate stalls. If 168 * a fatal signal is received, it will return with -EINTR immediately, 169 * without finishing destroying the whole range. Upon successful 170 * completion, 0 is returned. 171 */ 172 static inline int s390_uv_destroy_range_interruptible(struct mm_struct *mm, unsigned long start, 173 unsigned long end) 174 { 175 return __s390_uv_destroy_range(mm, start, end, true); 176 } 177 #endif /* _ASM_S390_GMAP_H */ 178