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 #include <linux/refcount.h>
  13
  14 /* Generic bits for GMAP notification on DAT table entry changes. */
  15 #define GMAP_NOTIFY_SHADOW      0x2
  16 #define GMAP_NOTIFY_MPROT       0x1
  17
  18 /* Status bits only for huge segment entries */
  19 #define _SEGMENT_ENTRY_GMAP_IN          0x8000  /* invalidation notify bit */
  20 #define _SEGMENT_ENTRY_GMAP_UC          0x4000  /* dirty (migration) */
  21
  22 /**
  23  * struct gmap_struct - guest address space
  24  * @list: list head for the mm->context gmap list
  25  * @crst_list: list of all crst tables used in the guest address space
  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  * @host_to_rmap: radix tree with gmap_rmap lists
  35  * @children: list of shadow gmap structures
  36  * @pt_list: list of all page tables used in the shadow guest address space
  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 list_head crst_list;
  47         struct mm_struct *mm;
  48         struct radix_tree_root guest_to_host;
  49         struct radix_tree_root host_to_guest;
  50         spinlock_t guest_table_lock;
  51         refcount_t ref_count;
  52         unsigned long *table;
  53         unsigned long asce;
  54         unsigned long asce_end;
  55         void *private;
  56         bool pfault_enabled;
  57         /* Additional data for shadow guest address spaces */
  58         struct radix_tree_root host_to_rmap;
  59         struct list_head children;
  60         struct list_head pt_list;
  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
 106 void gmap_enable(struct gmap *gmap);
 107 void gmap_disable(struct gmap *gmap);
 108 struct gmap *gmap_get_enabled(void);
 109 int gmap_map_segment(struct gmap *gmap, unsigned long from,
 110                      unsigned long to, unsigned long len);
 111 int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len);
 112 unsigned long __gmap_translate(struct gmap *, unsigned long gaddr);
 113 unsigned long gmap_translate(struct gmap *, unsigned long gaddr);
 114 int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr);
 115 int gmap_fault(struct gmap *, unsigned long gaddr, unsigned int fault_flags);
 116 void gmap_discard(struct gmap *, unsigned long from, unsigned long to);
 117 void __gmap_zap(struct gmap *, unsigned long gaddr);
 118 void gmap_unlink(struct mm_struct *, unsigned long *table, unsigned long vmaddr);
 119
 120 int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
 121
 122 struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
 123                          int edat_level);
 124 int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level);
 125 int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
 126                     int fake);
 127 int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
 128                     int fake);
 129 int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
 130                     int fake);
 131 int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
 132                     int fake);
 133 int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
 134                            unsigned long *pgt, int *dat_protection, int *fake);
 135 int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte);
 136
 137 void gmap_register_pte_notifier(struct gmap_notifier *);
 138 void gmap_unregister_pte_notifier(struct gmap_notifier *);
 139 void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *,
 140                      unsigned long bits);
 141
 142 int gmap_mprotect_notify(struct gmap *, unsigned long start,
 143                          unsigned long len, int prot);
 144
 145 void gmap_sync_dirty_log_pmd(struct gmap *gmap, unsigned long dirty_bitmap[4],
 146                              unsigned long gaddr, unsigned long vmaddr);
 147 #endif /* _ASM_S390_GMAP_H */