LXR linux/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/* Generic bits for GMAP notification on DAT table entry changes. */
  13#define GMAP_NOTIFY_SHADOW      0x2
  14#define GMAP_NOTIFY_MPROT       0x1
  15
  16/* Status bits only for huge segment entries */
  17#define _SEGMENT_ENTRY_GMAP_IN          0x8000  /* invalidation notify bit */
  18#define _SEGMENT_ENTRY_GMAP_UC          0x4000  /* dirty (migration) */
  19
  20/**
  21 * struct gmap_struct - guest address space
  22 * @list: list head for the mm->context gmap list
  23 * @crst_list: list of all crst tables used in the guest address space
  24 * @mm: pointer to the parent mm_struct
  25 * @guest_to_host: radix tree with guest to host address translation
  26 * @host_to_guest: radix tree with pointer to segment table entries
  27 * @guest_table_lock: spinlock to protect all entries in the guest page table
  28 * @ref_count: reference counter for the gmap structure
  29 * @table: pointer to the page directory
  30 * @asce: address space control element for gmap page table
  31 * @pfault_enabled: defines if pfaults are applicable for the guest
  32 * @host_to_rmap: radix tree with gmap_rmap lists
  33 * @children: list of shadow gmap structures
  34 * @pt_list: list of all page tables used in the shadow guest address space
  35 * @shadow_lock: spinlock to protect the shadow gmap list
  36 * @parent: pointer to the parent gmap for shadow guest address spaces
  37 * @orig_asce: ASCE for which the shadow page table has been created
  38 * @edat_level: edat level to be used for the shadow translation
  39 * @removed: flag to indicate if a shadow guest address space has been removed
  40 * @initialized: flag to indicate if a shadow guest address space can be used
  41 */
  42struct gmap {
  43        struct list_head list;
  44        struct list_head crst_list;
  45        struct mm_struct *mm;
  46        struct radix_tree_root guest_to_host;
  47        struct radix_tree_root host_to_guest;
  48        spinlock_t guest_table_lock;
  49        atomic_t ref_count;
  50        unsigned long *table;
  51        unsigned long asce;
  52        unsigned long asce_end;
  53        void *private;
  54        bool pfault_enabled;
  55        /* Additional data for shadow guest address spaces */
  56        struct radix_tree_root host_to_rmap;
  57        struct list_head children;
  58        struct list_head pt_list;
  59        spinlock_t shadow_lock;
  60        struct gmap *parent;
  61        unsigned long orig_asce;
  62        int edat_level;
  63        bool removed;
  64        bool initialized;
  65};
  66
  67/**
  68 * struct gmap_rmap - reverse mapping for shadow page table entries
  69 * @next: pointer to next rmap in the list
  70 * @raddr: virtual rmap address in the shadow guest address space
  71 */
  72struct gmap_rmap {
  73        struct gmap_rmap *next;
  74        unsigned long raddr;
  75};
  76
  77#define gmap_for_each_rmap(pos, head) \
  78        for (pos = (head); pos; pos = pos->next)
  79
  80#define gmap_for_each_rmap_safe(pos, n, head) \
  81        for (pos = (head); n = pos ? pos->next : NULL, pos; pos = n)
  82
  83/**
  84 * struct gmap_notifier - notify function block for page invalidation
  85 * @notifier_call: address of callback function
  86 */
  87struct gmap_notifier {
  88        struct list_head list;
  89        struct rcu_head rcu;
  90        void (*notifier_call)(struct gmap *gmap, unsigned long start,
  91                              unsigned long end);
  92};
  93
  94static inline int gmap_is_shadow(struct gmap *gmap)
  95{
  96        return !!gmap->parent;
  97}
  98
  99struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit);
 100void gmap_remove(struct gmap *gmap);
 101struct gmap *gmap_get(struct gmap *gmap);
 102void gmap_put(struct gmap *gmap);
 103
 104void gmap_enable(struct gmap *gmap);
 105void gmap_disable(struct gmap *gmap);
 106struct gmap *gmap_get_enabled(void);
 107int gmap_map_segment(struct gmap *gmap, unsigned long from,
 108                     unsigned long to, unsigned long len);
 109int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len);
 110unsigned long __gmap_translate(struct gmap *, unsigned long gaddr);
 111unsigned long gmap_translate(struct gmap *, unsigned long gaddr);
 112int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr);
 113int gmap_fault(struct gmap *, unsigned long gaddr, unsigned int fault_flags);
 114void gmap_discard(struct gmap *, unsigned long from, unsigned long to);
 115void __gmap_zap(struct gmap *, unsigned long gaddr);
 116void gmap_unlink(struct mm_struct *, unsigned long *table, unsigned long vmaddr);
 117
 118int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
 119
 120struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
 121                         int edat_level);
 122int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level);
 123int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
 124                    int fake);
 125int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
 126                    int fake);
 127int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
 128                    int fake);
 129int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
 130                    int fake);
 131int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
 132                           unsigned long *pgt, int *dat_protection, int *fake);
 133int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte);
 134
 135void gmap_register_pte_notifier(struct gmap_notifier *);
 136void gmap_unregister_pte_notifier(struct gmap_notifier *);
 137void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *,
 138                     unsigned long bits);
 139
 140int gmap_mprotect_notify(struct gmap *, unsigned long start,
 141                         unsigned long len, int prot);
 142
 143void gmap_sync_dirty_log_pmd(struct gmap *gmap, unsigned long dirty_bitmap[4],
 144                             unsigned long gaddr, unsigned long vmaddr);
 145#endif /* _ASM_S390_GMAP_H */
 146