1#ifndef _LGUEST_H
2#define _LGUEST_H
3
4#ifndef __ASSEMBLY__
5#include <linux/types.h>
6#include <linux/init.h>
7#include <linux/stringify.h>
8#include <linux/lguest.h>
9#include <linux/lguest_launcher.h>
10#include <linux/wait.h>
11#include <linux/hrtimer.h>
12#include <linux/err.h>
13#include <linux/slab.h>
14
15#include <asm/lguest.h>
16
17struct pgdir {
18	unsigned long gpgdir;
19	bool switcher_mapped;
20	int last_host_cpu;
21	pgd_t *pgdir;
22};
23
24/* We have two pages shared with guests, per cpu.  */
25struct lguest_pages {
26	/* This is the stack page mapped rw in guest */
27	char spare[PAGE_SIZE - sizeof(struct lguest_regs)];
28	struct lguest_regs regs;
29
30	/* This is the host state & guest descriptor page, ro in guest */
31	struct lguest_ro_state state;
32} __attribute__((aligned(PAGE_SIZE)));
33
34#define CHANGED_IDT		1
35#define CHANGED_GDT		2
36#define CHANGED_GDT_TLS		4 /* Actually a subset of CHANGED_GDT */
37#define CHANGED_ALL	        3
38
39struct lg_cpu {
40	unsigned int id;
41	struct lguest *lg;
42	struct task_struct *tsk;
43	struct mm_struct *mm; 	/* == tsk->mm, but that becomes NULL on exit */
44
45	u32 cr2;
46	int ts;
47	u32 esp1;
48	u16 ss1;
49
50	/* Bitmap of what has changed: see CHANGED_* above. */
51	int changed;
52
53	/* Pending operation. */
54	struct lguest_pending pending;
55
56	unsigned long *reg_read; /* register from LHREQ_GETREG */
57
58	/* At end of a page shared mapped over lguest_pages in guest. */
59	unsigned long regs_page;
60	struct lguest_regs *regs;
61
62	struct lguest_pages *last_pages;
63
64	/* Initialization mode: linear map everything. */
65	bool linear_pages;
66	int cpu_pgd; /* Which pgd this cpu is currently using */
67
68	/* If a hypercall was asked for, this points to the arguments. */
69	struct hcall_args *hcall;
70	u32 next_hcall;
71
72	/* Virtual clock device */
73	struct hrtimer hrt;
74
75	/* Did the Guest tell us to halt? */
76	int halted;
77
78	/* Pending virtual interrupts */
79	DECLARE_BITMAP(irqs_pending, LGUEST_IRQS);
80
81	struct lg_cpu_arch arch;
82};
83
84/* The private info the thread maintains about the guest. */
85struct lguest {
86	struct lguest_data __user *lguest_data;
87	struct lg_cpu cpus[NR_CPUS];
88	unsigned int nr_cpus;
89
90	/* Valid guest memory pages must be < this. */
91	u32 pfn_limit;
92
93	/* Device memory is >= pfn_limit and < device_limit. */
94	u32 device_limit;
95
96	/*
97	 * This provides the offset to the base of guest-physical memory in the
98	 * Launcher.
99	 */
100	void __user *mem_base;
101	unsigned long kernel_address;
102
103	struct pgdir pgdirs[4];
104
105	unsigned long noirq_iret;
106
107	unsigned int stack_pages;
108	u32 tsc_khz;
109
110	/* Dead? */
111	const char *dead;
112};
113
114extern struct mutex lguest_lock;
115
116/* core.c: */
117bool lguest_address_ok(const struct lguest *lg,
118		       unsigned long addr, unsigned long len);
119void __lgread(struct lg_cpu *, void *, unsigned long, unsigned);
120void __lgwrite(struct lg_cpu *, unsigned long, const void *, unsigned);
121extern struct page **lg_switcher_pages;
122
123/*H:035
124 * Using memory-copy operations like that is usually inconvient, so we
125 * have the following helper macros which read and write a specific type (often
126 * an unsigned long).
127 *
128 * This reads into a variable of the given type then returns that.
129 */
130#define lgread(cpu, addr, type)						\
131	({ type _v; __lgread((cpu), &_v, (addr), sizeof(_v)); _v; })
132
133/* This checks that the variable is of the given type, then writes it out. */
134#define lgwrite(cpu, addr, type, val)				\
135	do {							\
136		typecheck(type, val);				\
137		__lgwrite((cpu), (addr), &(val), sizeof(val));	\
138	} while(0)
139/* (end of memory access helper routines) :*/
140
141int run_guest(struct lg_cpu *cpu, unsigned long __user *user);
142
143/*
144 * Helper macros to obtain the first 12 or the last 20 bits, this is only the
145 * first step in the migration to the kernel types.  pte_pfn is already defined
146 * in the kernel.
147 */
148#define pgd_flags(x)	(pgd_val(x) & ~PAGE_MASK)
149#define pgd_pfn(x)	(pgd_val(x) >> PAGE_SHIFT)
150#define pmd_flags(x)    (pmd_val(x) & ~PAGE_MASK)
151#define pmd_pfn(x)	(pmd_val(x) >> PAGE_SHIFT)
152
153/* interrupts_and_traps.c: */
154unsigned int interrupt_pending(struct lg_cpu *cpu, bool *more);
155void try_deliver_interrupt(struct lg_cpu *cpu, unsigned int irq, bool more);
156void set_interrupt(struct lg_cpu *cpu, unsigned int irq);
157bool deliver_trap(struct lg_cpu *cpu, unsigned int num);
158void load_guest_idt_entry(struct lg_cpu *cpu, unsigned int i,
159			  u32 low, u32 hi);
160void guest_set_stack(struct lg_cpu *cpu, u32 seg, u32 esp, unsigned int pages);
161void pin_stack_pages(struct lg_cpu *cpu);
162void setup_default_idt_entries(struct lguest_ro_state *state,
163			       const unsigned long *def);
164void copy_traps(const struct lg_cpu *cpu, struct desc_struct *idt,
165		const unsigned long *def);
166void guest_set_clockevent(struct lg_cpu *cpu, unsigned long delta);
167bool send_notify_to_eventfd(struct lg_cpu *cpu);
168void init_clockdev(struct lg_cpu *cpu);
169bool check_syscall_vector(struct lguest *lg);
170int init_interrupts(void);
171void free_interrupts(void);
172
173/* segments.c: */
174void setup_default_gdt_entries(struct lguest_ro_state *state);
175void setup_guest_gdt(struct lg_cpu *cpu);
176void load_guest_gdt_entry(struct lg_cpu *cpu, unsigned int i,
177			  u32 low, u32 hi);
178void guest_load_tls(struct lg_cpu *cpu, unsigned long tls_array);
179void copy_gdt(const struct lg_cpu *cpu, struct desc_struct *gdt);
180void copy_gdt_tls(const struct lg_cpu *cpu, struct desc_struct *gdt);
181
182/* page_tables.c: */
183int init_guest_pagetable(struct lguest *lg);
184void free_guest_pagetable(struct lguest *lg);
185void guest_new_pagetable(struct lg_cpu *cpu, unsigned long pgtable);
186void guest_set_pgd(struct lguest *lg, unsigned long gpgdir, u32 i);
187#ifdef CONFIG_X86_PAE
188void guest_set_pmd(struct lguest *lg, unsigned long gpgdir, u32 i);
189#endif
190void guest_pagetable_clear_all(struct lg_cpu *cpu);
191void guest_pagetable_flush_user(struct lg_cpu *cpu);
192void guest_set_pte(struct lg_cpu *cpu, unsigned long gpgdir,
193		   unsigned long vaddr, pte_t val);
194void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages);
195bool demand_page(struct lg_cpu *cpu, unsigned long cr2, int errcode,
196		 unsigned long *iomem);
197void pin_page(struct lg_cpu *cpu, unsigned long vaddr);
198bool __guest_pa(struct lg_cpu *cpu, unsigned long vaddr, unsigned long *paddr);
199unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr);
200void page_table_guest_data_init(struct lg_cpu *cpu);
201
202/* <arch>/core.c: */
203void lguest_arch_host_init(void);
204void lguest_arch_host_fini(void);
205void lguest_arch_run_guest(struct lg_cpu *cpu);
206void lguest_arch_handle_trap(struct lg_cpu *cpu);
207int lguest_arch_init_hypercalls(struct lg_cpu *cpu);
208int lguest_arch_do_hcall(struct lg_cpu *cpu, struct hcall_args *args);
209void lguest_arch_setup_regs(struct lg_cpu *cpu, unsigned long start);
210unsigned long *lguest_arch_regptr(struct lg_cpu *cpu, size_t reg_off, bool any);
211
212/* <arch>/switcher.S: */
213extern char start_switcher_text[], end_switcher_text[], switch_to_guest[];
214
215/* lguest_user.c: */
216int lguest_device_init(void);
217void lguest_device_remove(void);
218
219/* hypercalls.c: */
220void do_hypercalls(struct lg_cpu *cpu);
221void write_timestamp(struct lg_cpu *cpu);
222
223/*L:035
224 * Let's step aside for the moment, to study one important routine that's used
225 * widely in the Host code.
226 *
227 * There are many cases where the Guest can do something invalid, like pass crap
228 * to a hypercall.  Since only the Guest kernel can make hypercalls, it's quite
229 * acceptable to simply terminate the Guest and give the Launcher a nicely
230 * formatted reason.  It's also simpler for the Guest itself, which doesn't
231 * need to check most hypercalls for "success"; if you're still running, it
232 * succeeded.
233 *
234 * Once this is called, the Guest will never run again, so most Host code can
235 * call this then continue as if nothing had happened.  This means many
236 * functions don't have to explicitly return an error code, which keeps the
237 * code simple.
238 *
239 * It also means that this can be called more than once: only the first one is
240 * remembered.  The only trick is that we still need to kill the Guest even if
241 * we can't allocate memory to store the reason.  Linux has a neat way of
242 * packing error codes into invalid pointers, so we use that here.
243 *
244 * Like any macro which uses an "if", it is safely wrapped in a run-once "do {
245 * } while(0)".
246 */
247#define kill_guest(cpu, fmt...)					\
248do {								\
249	if (!(cpu)->lg->dead) {					\
250		(cpu)->lg->dead = kasprintf(GFP_ATOMIC, fmt);	\
251		if (!(cpu)->lg->dead)				\
252			(cpu)->lg->dead = ERR_PTR(-ENOMEM);	\
253	}							\
254} while(0)
255/* (End of aside) :*/
256
257#endif	/* __ASSEMBLY__ */
258#endif	/* _LGUEST_H */
259