xref: /openbmc/linux/arch/s390/include/asm/gmap.h (revision 09b35b41)
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 */
148