xref: /linux/arch/s390/include/asm/gmap.h (revision b2d0f5d5dc53532e6f07bc546a476a55ebdfe0f3)
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 */
136