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