xref: /openbmc/linux/arch/s390/include/asm/gmap.h (revision 6d99a79c)
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  */
42 struct 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  */
72 struct 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  */
87 struct 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 
94 static inline int gmap_is_shadow(struct gmap *gmap)
95 {
96 	return !!gmap->parent;
97 }
98 
99 struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit);
100 void gmap_remove(struct gmap *gmap);
101 struct gmap *gmap_get(struct gmap *gmap);
102 void gmap_put(struct gmap *gmap);
103 
104 void gmap_enable(struct gmap *gmap);
105 void gmap_disable(struct gmap *gmap);
106 struct gmap *gmap_get_enabled(void);
107 int gmap_map_segment(struct gmap *gmap, unsigned long from,
108 		     unsigned long to, unsigned long len);
109 int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len);
110 unsigned long __gmap_translate(struct gmap *, unsigned long gaddr);
111 unsigned long gmap_translate(struct gmap *, unsigned long gaddr);
112 int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr);
113 int gmap_fault(struct gmap *, unsigned long gaddr, unsigned int fault_flags);
114 void gmap_discard(struct gmap *, unsigned long from, unsigned long to);
115 void __gmap_zap(struct gmap *, unsigned long gaddr);
116 void gmap_unlink(struct mm_struct *, unsigned long *table, unsigned long vmaddr);
117 
118 int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
119 
120 struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
121 			 int edat_level);
122 int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level);
123 int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
124 		    int fake);
125 int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
126 		    int fake);
127 int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
128 		    int fake);
129 int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
130 		    int fake);
131 int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
132 			   unsigned long *pgt, int *dat_protection, int *fake);
133 int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte);
134 
135 void gmap_register_pte_notifier(struct gmap_notifier *);
136 void gmap_unregister_pte_notifier(struct gmap_notifier *);
137 void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *,
138 		     unsigned long bits);
139 
140 int gmap_mprotect_notify(struct gmap *, unsigned long start,
141 			 unsigned long len, int prot);
142 
143 void 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