summaryrefslogtreecommitdiff
path: root/drivers/lguest/lg.h
blob: 3e2ddfbc816e9fc1396c8fe724e14e1732928502 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
#ifndef _LGUEST_H
#define _LGUEST_H

#include <asm/desc.h>

#define GDT_ENTRY_LGUEST_CS	10
#define GDT_ENTRY_LGUEST_DS	11
#define LGUEST_CS		(GDT_ENTRY_LGUEST_CS * 8)
#define LGUEST_DS		(GDT_ENTRY_LGUEST_DS * 8)

#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <linux/init.h>
#include <linux/stringify.h>
#include <linux/binfmts.h>
#include <linux/futex.h>
#include <linux/lguest.h>
#include <linux/lguest_launcher.h>
#include <linux/wait.h>
#include <linux/err.h>
#include <asm/semaphore.h>
#include "irq_vectors.h"

#define GUEST_PL 1

struct lguest_regs
{
	/* Manually saved part. */
	unsigned long ebx, ecx, edx;
	unsigned long esi, edi, ebp;
	unsigned long gs;
	unsigned long eax;
	unsigned long fs, ds, es;
	unsigned long trapnum, errcode;
	/* Trap pushed part */
	unsigned long eip;
	unsigned long cs;
	unsigned long eflags;
	unsigned long esp;
	unsigned long ss;
};

void free_pagetables(void);
int init_pagetables(struct page **switcher_page, unsigned int pages);

/* Full 4G segment descriptors, suitable for CS and DS. */
#define FULL_EXEC_SEGMENT ((struct desc_struct){0x0000ffff, 0x00cf9b00})
#define FULL_SEGMENT ((struct desc_struct){0x0000ffff, 0x00cf9300})

struct lguest_dma_info
{
	struct list_head list;
	union futex_key key;
	unsigned long dmas;
	u16 next_dma;
	u16 num_dmas;
	u16 guestid;
	u8 interrupt; 	/* 0 when not registered */
};

/* We have separate types for the guest's ptes & pgds and the shadow ptes &
 * pgds.  Since this host might use three-level pagetables and the guest and
 * shadow pagetables don't, we can't use the normal pte_t/pgd_t. */
typedef union {
	struct { unsigned flags:12, pfn:20; };
	struct { unsigned long val; } raw;
} spgd_t;
typedef union {
	struct { unsigned flags:12, pfn:20; };
	struct { unsigned long val; } raw;
} spte_t;
typedef union {
	struct { unsigned flags:12, pfn:20; };
	struct { unsigned long val; } raw;
} gpgd_t;
typedef union {
	struct { unsigned flags:12, pfn:20; };
	struct { unsigned long val; } raw;
} gpte_t;
#define mkgpte(_val) ((gpte_t){.raw.val = _val})
#define mkgpgd(_val) ((gpgd_t){.raw.val = _val})

struct pgdir
{
	unsigned long cr3;
	spgd_t *pgdir;
};

/* This is a guest-specific page (mapped ro) into the guest. */
struct lguest_ro_state
{
	/* Host information we need to restore when we switch back. */
	u32 host_cr3;
	struct Xgt_desc_struct host_idt_desc;
	struct Xgt_desc_struct host_gdt_desc;
	u32 host_sp;

	/* Fields which are used when guest is running. */
	struct Xgt_desc_struct guest_idt_desc;
	struct Xgt_desc_struct guest_gdt_desc;
	struct i386_hw_tss guest_tss;
	struct desc_struct guest_idt[IDT_ENTRIES];
	struct desc_struct guest_gdt[GDT_ENTRIES];
};

/* We have two pages shared with guests, per cpu.  */
struct lguest_pages
{
	/* This is the stack page mapped rw in guest */
	char spare[PAGE_SIZE - sizeof(struct lguest_regs)];
	struct lguest_regs regs;

	/* This is the host state & guest descriptor page, ro in guest */
	struct lguest_ro_state state;
} __attribute__((aligned(PAGE_SIZE)));

#define CHANGED_IDT		1
#define CHANGED_GDT		2
#define CHANGED_GDT_TLS		4 /* Actually a subset of CHANGED_GDT */
#define CHANGED_ALL	        3

/* The private info the thread maintains about the guest. */
struct lguest
{
	/* At end of a page shared mapped over lguest_pages in guest.  */
	unsigned long regs_page;
	struct lguest_regs *regs;
	struct lguest_data __user *lguest_data;
	struct task_struct *tsk;
	struct mm_struct *mm; 	/* == tsk->mm, but that becomes NULL on exit */
	u16 guestid;
	u32 pfn_limit;
	u32 page_offset;
	u32 cr2;
	int halted;
	int ts;
	u32 next_hcall;
	u32 esp1;
	u8 ss1;

	/* Do we need to stop what we're doing and return to userspace? */
	int break_out;
	wait_queue_head_t break_wq;

	/* Bitmap of what has changed: see CHANGED_* above. */
	int changed;
	struct lguest_pages *last_pages;

	/* We keep a small number of these. */
	u32 pgdidx;
	struct pgdir pgdirs[4];

	/* Cached wakeup: we hold a reference to this task. */
	struct task_struct *wake;

	unsigned long noirq_start, noirq_end;
	int dma_is_pending;
	unsigned long pending_dma; /* struct lguest_dma */
	unsigned long pending_key; /* address they're sending to */

	unsigned int stack_pages;
	u32 tsc_khz;

	struct lguest_dma_info dma[LGUEST_MAX_DMA];

	/* Dead? */
	const char *dead;

	/* The GDT entries copied into lguest_ro_state when running. */
	struct desc_struct gdt[GDT_ENTRIES];

	/* The IDT entries: some copied into lguest_ro_state when running. */
	struct desc_struct idt[FIRST_EXTERNAL_VECTOR+LGUEST_IRQS];
	struct desc_struct syscall_idt;

	/* Virtual clock device */
	struct hrtimer hrt;

	/* Pending virtual interrupts */
	DECLARE_BITMAP(irqs_pending, LGUEST_IRQS);
};

extern struct lguest lguests[];
extern struct mutex lguest_lock;

/* core.c: */
u32 lgread_u32(struct lguest *lg, unsigned long addr);
void lgwrite_u32(struct lguest *lg, unsigned long addr, u32 val);
void lgread(struct lguest *lg, void *buf, unsigned long addr, unsigned len);
void lgwrite(struct lguest *lg, unsigned long, const void *buf, unsigned len);
int find_free_guest(void);
int lguest_address_ok(const struct lguest *lg,
		      unsigned long addr, unsigned long len);
int run_guest(struct lguest *lg, unsigned long __user *user);


/* interrupts_and_traps.c: */
void maybe_do_interrupt(struct lguest *lg);
int deliver_trap(struct lguest *lg, unsigned int num);
void load_guest_idt_entry(struct lguest *lg, unsigned int i, u32 low, u32 hi);
void guest_set_stack(struct lguest *lg, u32 seg, u32 esp, unsigned int pages);
void pin_stack_pages(struct lguest *lg);
void setup_default_idt_entries(struct lguest_ro_state *state,
			       const unsigned long *def);
void copy_traps(const struct lguest *lg, struct desc_struct *idt,
		const unsigned long *def);
void guest_set_clockevent(struct lguest *lg, unsigned long delta);
void init_clockdev(struct lguest *lg);

/* segments.c: */
void setup_default_gdt_entries(struct lguest_ro_state *state);
void setup_guest_gdt(struct lguest *lg);
void load_guest_gdt(struct lguest *lg, unsigned long table, u32 num);
void guest_load_tls(struct lguest *lg, unsigned long tls_array);
void copy_gdt(const struct lguest *lg, struct desc_struct *gdt);
void copy_gdt_tls(const struct lguest *lg, struct desc_struct *gdt);

/* page_tables.c: */
int init_guest_pagetable(struct lguest *lg, unsigned long pgtable);
void free_guest_pagetable(struct lguest *lg);
void guest_new_pagetable(struct lguest *lg, unsigned long pgtable);
void guest_set_pmd(struct lguest *lg, unsigned long cr3, u32 i);
void guest_pagetable_clear_all(struct lguest *lg);
void guest_pagetable_flush_user(struct lguest *lg);
void guest_set_pte(struct lguest *lg, unsigned long cr3,
		   unsigned long vaddr, gpte_t val);
void map_switcher_in_guest(struct lguest *lg, struct lguest_pages *pages);
int demand_page(struct lguest *info, unsigned long cr2, int errcode);
void pin_page(struct lguest *lg, unsigned long vaddr);

/* lguest_user.c: */
int lguest_device_init(void);
void lguest_device_remove(void);

/* io.c: */
void lguest_io_init(void);
int bind_dma(struct lguest *lg,
	     unsigned long key, unsigned long udma, u16 numdmas, u8 interrupt);
void send_dma(struct lguest *info, unsigned long key, unsigned long udma);
void release_all_dma(struct lguest *lg);
unsigned long get_dma_buffer(struct lguest *lg, unsigned long key,
			     unsigned long *interrupt);

/* hypercalls.c: */
void do_hypercalls(struct lguest *lg);

#define kill_guest(lg, fmt...)					\
do {								\
	if (!(lg)->dead) {					\
		(lg)->dead = kasprintf(GFP_ATOMIC, fmt);	\
		if (!(lg)->dead)				\
			(lg)->dead = ERR_PTR(-ENOMEM);		\
	}							\
} while(0)

static inline unsigned long guest_pa(struct lguest *lg, unsigned long vaddr)
{
	return vaddr - lg->page_offset;
}
#endif	/* __ASSEMBLY__ */
#endif	/* _LGUEST_H */