arch/s390/include/asm/gmap.h

   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 /**
  13  * struct gmap_struct - guest address space
  14  * @list: list head for the mm->context gmap list
  15  * @crst_list: list of all crst tables used in the guest address space
  16  * @mm: pointer to the parent mm_struct
  17  * @guest_to_host: radix tree with guest to host address translation
  18  * @host_to_guest: radix tree with pointer to segment table entries
  19  * @guest_table_lock: spinlock to protect all entries in the guest page table
  20  * @ref_count: reference counter for the gmap structure
  21  * @table: pointer to the page directory
  22  * @asce: address space control element for gmap page table
  23  * @pfault_enabled: defines if pfaults are applicable for the guest
  24  * @host_to_rmap: radix tree with gmap_rmap lists
  25  * @children: list of shadow gmap structures
  26  * @pt_list: list of all page tables used in the shadow guest address space
  27  * @shadow_lock: spinlock to protect the shadow gmap list
  28  * @parent: pointer to the parent gmap for shadow guest address spaces
  29  * @orig_asce: ASCE for which the shadow page table has been created
  30  * @edat_level: edat level to be used for the shadow translation
  31  * @removed: flag to indicate if a shadow guest address space has been removed
  32  * @initialized: flag to indicate if a shadow guest address space can be used
  33  */
  34 struct gmap {
  35         struct list_head list;
  36         struct list_head crst_list;
  37         struct mm_struct *mm;
  38         struct radix_tree_root guest_to_host;
  39         struct radix_tree_root host_to_guest;
  40         spinlock_t guest_table_lock;
  41         atomic_t ref_count;
  42         unsigned long *table;
  43         unsigned long asce;
  44         unsigned long asce_end;
  45         void *private;
  46         bool pfault_enabled;
  47         /* Additional data for shadow guest address spaces */
  48         struct radix_tree_root host_to_rmap;
  49         struct list_head children;
  50         struct list_head pt_list;
  51         spinlock_t shadow_lock;
  52         struct gmap *parent;
  53         unsigned long orig_asce;
  54         int edat_level;
  55         bool removed;
  56         bool initialized;
  57 };
  58
  59 /**
  60  * struct gmap_rmap - reverse mapping for shadow page table entries
  61  * @next: pointer to next rmap in the list
  62  * @raddr: virtual rmap address in the shadow guest address space
  63  */
  64 struct gmap_rmap {
  65         struct gmap_rmap *next;
  66         unsigned long raddr;
  67 };
  68
  69 #define gmap_for_each_rmap(pos, head) \
  70         for (pos = (head); pos; pos = pos->next)
  71
  72 #define gmap_for_each_rmap_safe(pos, n, head) \
  73         for (pos = (head); n = pos ? pos->next : NULL, pos; pos = n)
  74
  75 /**
  76  * struct gmap_notifier - notify function block for page invalidation
  77  * @notifier_call: address of callback function
  78  */
  79 struct gmap_notifier {
  80         struct list_head list;
  81         struct rcu_head rcu;
  82         void (*notifier_call)(struct gmap *gmap, unsigned long start,
  83                               unsigned long end);
  84 };
  85
  86 static inline int gmap_is_shadow(struct gmap *gmap)
  87 {
  88         return !!gmap->parent;
  89 }
  90
  91 struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit);
  92 void gmap_remove(struct gmap *gmap);
  93 struct gmap *gmap_get(struct gmap *gmap);
  94 void gmap_put(struct gmap *gmap);
  95
  96 void gmap_enable(struct gmap *gmap);
  97 void gmap_disable(struct gmap *gmap);
  98 struct gmap *gmap_get_enabled(void);
  99 int gmap_map_segment(struct gmap *gmap, unsigned long from,
 100                      unsigned long to, unsigned long len);
 101 int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len);
 102 unsigned long __gmap_translate(struct gmap *, unsigned long gaddr);
 103 unsigned long gmap_translate(struct gmap *, unsigned long gaddr);
 104 int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr);
 105 int gmap_fault(struct gmap *, unsigned long gaddr, unsigned int fault_flags);
 106 void gmap_discard(struct gmap *, unsigned long from, unsigned long to);
 107 void __gmap_zap(struct gmap *, unsigned long gaddr);
 108 void gmap_unlink(struct mm_struct *, unsigned long *table, unsigned long vmaddr);
 109
 110 int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
 111
 112 struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
 113                          int edat_level);
 114 int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level);
 115 int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
 116                     int fake);
 117 int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
 118                     int fake);
 119 int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
 120                     int fake);
 121 int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
 122                     int fake);
 123 int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
 124                            unsigned long *pgt, int *dat_protection, int *fake);
 125 int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte);
 126
 127 void gmap_register_pte_notifier(struct gmap_notifier *);
 128 void gmap_unregister_pte_notifier(struct gmap_notifier *);
 129 void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *,
 130                      unsigned long bits);
 131
 132 int gmap_mprotect_notify(struct gmap *, unsigned long start,
 133                          unsigned long len, int prot);
 134
 135 #endif /* _ASM_S390_GMAP_H */