arch/s390/include/asm/gmap.h

   1 /*
   2  *  KVM guest address space mapping code
   3  *
   4  *    Copyright IBM Corp. 2007, 2016
   5  *    Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
   6  */
   7
   8 #ifndef _ASM_S390_GMAP_H
   9 #define _ASM_S390_GMAP_H
  10
  11 /**
  12  * struct gmap_struct - guest address space
  13  * @list: list head for the mm->context gmap list
  14  * @crst_list: list of all crst tables used in the guest address space
  15  * @mm: pointer to the parent mm_struct
  16  * @guest_to_host: radix tree with guest to host address translation
  17  * @host_to_guest: radix tree with pointer to segment table entries
  18  * @guest_table_lock: spinlock to protect all entries in the guest page table
  19  * @ref_count: reference counter for the gmap structure
  20  * @table: pointer to the page directory
  21  * @asce: address space control element for gmap page table
  22  * @pfault_enabled: defines if pfaults are applicable for the guest
  23  * @host_to_rmap: radix tree with gmap_rmap lists
  24  * @children: list of shadow gmap structures
  25  * @pt_list: list of all page tables used in the shadow guest address space
  26  * @shadow_lock: spinlock to protect the shadow gmap list
  27  * @parent: pointer to the parent gmap for shadow guest address spaces
  28  * @orig_asce: ASCE for which the shadow page table has been created
  29  * @removed: flag to indicate if a shadow guest address space has been removed
  30  */
  31 struct gmap {
  32         struct list_head list;
  33         struct list_head crst_list;
  34         struct mm_struct *mm;
  35         struct radix_tree_root guest_to_host;
  36         struct radix_tree_root host_to_guest;
  37         spinlock_t guest_table_lock;
  38         atomic_t ref_count;
  39         unsigned long *table;
  40         unsigned long asce;
  41         unsigned long asce_end;
  42         void *private;
  43         bool pfault_enabled;
  44         /* Additional data for shadow guest address spaces */
  45         struct radix_tree_root host_to_rmap;
  46         struct list_head children;
  47         struct list_head pt_list;
  48         spinlock_t shadow_lock;
  49         struct gmap *parent;
  50         unsigned long orig_asce;
  51         bool removed;
  52 };
  53
  54 /**
  55  * struct gmap_rmap - reverse mapping for shadow page table entries
  56  * @next: pointer to next rmap in the list
  57  * @raddr: virtual rmap address in the shadow guest address space
  58  */
  59 struct gmap_rmap {
  60         struct gmap_rmap *next;
  61         unsigned long raddr;
  62 };
  63
  64 #define gmap_for_each_rmap(pos, head) \
  65         for (pos = (head); pos; pos = pos->next)
  66
  67 #define gmap_for_each_rmap_safe(pos, n, head) \
  68         for (pos = (head); n = pos ? pos->next : NULL, pos; pos = n)
  69
  70 /**
  71  * struct gmap_notifier - notify function block for page invalidation
  72  * @notifier_call: address of callback function
  73  */
  74 struct gmap_notifier {
  75         struct list_head list;
  76         struct rcu_head rcu;
  77         void (*notifier_call)(struct gmap *gmap, unsigned long start,
  78                               unsigned long end);
  79 };
  80
  81 static inline int gmap_is_shadow(struct gmap *gmap)
  82 {
  83         return !!gmap->parent;
  84 }
  85
  86 struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit);
  87 void gmap_remove(struct gmap *gmap);
  88 struct gmap *gmap_get(struct gmap *gmap);
  89 void gmap_put(struct gmap *gmap);
  90
  91 void gmap_enable(struct gmap *gmap);
  92 void gmap_disable(struct gmap *gmap);
  93 int gmap_map_segment(struct gmap *gmap, unsigned long from,
  94                      unsigned long to, unsigned long len);
  95 int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len);
  96 unsigned long __gmap_translate(struct gmap *, unsigned long gaddr);
  97 unsigned long gmap_translate(struct gmap *, unsigned long gaddr);
  98 int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr);
  99 int gmap_fault(struct gmap *, unsigned long gaddr, unsigned int fault_flags);
 100 void gmap_discard(struct gmap *, unsigned long from, unsigned long to);
 101 void __gmap_zap(struct gmap *, unsigned long gaddr);
 102 void gmap_unlink(struct mm_struct *, unsigned long *table, unsigned long vmaddr);
 103
 104 int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
 105
 106 struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce);
 107 int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t);
 108 int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t);
 109 int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt);
 110 int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt);
 111 int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
 112                            unsigned long *pgt, int *dat_protection);
 113 int gmap_shadow_page(struct gmap *sg, unsigned long saddr,
 114                      unsigned long paddr, int write);
 115
 116 void gmap_register_pte_notifier(struct gmap_notifier *);
 117 void gmap_unregister_pte_notifier(struct gmap_notifier *);
 118 void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *,
 119                      unsigned long bits);
 120
 121 int gmap_mprotect_notify(struct gmap *, unsigned long start,
 122                          unsigned long len, int prot);
 123
 124 #endif /* _ASM_S390_GMAP_H */