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>
14 #include <asm/lguest.h>
16 void free_pagetables(void);
17 int init_pagetables(struct page
**switcher_page
, unsigned int pages
);
25 /* We have two pages shared with guests, per cpu. */
28 /* This is the stack page mapped rw in guest */
29 char spare
[PAGE_SIZE
- sizeof(struct lguest_regs
)];
30 struct lguest_regs regs
;
32 /* This is the host state & guest descriptor page, ro in guest */
33 struct lguest_ro_state state
;
34 } __attribute__((aligned(PAGE_SIZE
)));
38 #define CHANGED_GDT_TLS 4 /* Actually a subset of CHANGED_GDT */
46 struct task_struct
*tsk
;
47 struct mm_struct
*mm
; /* == tsk->mm, but that becomes NULL on exit */
54 /* Bitmap of what has changed: see CHANGED_* above. */
57 unsigned long pending_notify
; /* pfn from LHCALL_NOTIFY */
59 /* At end of a page shared mapped over lguest_pages in guest. */
60 unsigned long regs_page
;
61 struct lguest_regs
*regs
;
63 struct lguest_pages
*last_pages
;
65 int cpu_pgd
; /* which pgd this cpu is currently using */
67 /* If a hypercall was asked for, this points to the arguments. */
68 struct hcall_args
*hcall
;
71 /* Virtual clock device */
74 /* Do we need to stop what we're doing and return to userspace? */
76 wait_queue_head_t break_wq
;
79 /* Pending virtual interrupts */
80 DECLARE_BITMAP(irqs_pending
, LGUEST_IRQS
);
82 struct lg_cpu_arch arch
;
85 /* The private info the thread maintains about the guest. */
88 struct lguest_data __user
*lguest_data
;
89 struct lg_cpu cpus
[NR_CPUS
];
93 /* This provides the offset to the base of guest-physical
94 * memory in the Launcher. */
95 void __user
*mem_base
;
96 unsigned long kernel_address
;
98 struct pgdir pgdirs
[4];
100 unsigned long noirq_start
, noirq_end
;
102 unsigned int stack_pages
;
109 extern struct mutex lguest_lock
;
112 bool lguest_address_ok(const struct lguest
*lg
,
113 unsigned long addr
, unsigned long len
);
114 void __lgread(struct lg_cpu
*, void *, unsigned long, unsigned);
115 void __lgwrite(struct lg_cpu
*, unsigned long, const void *, unsigned);
117 /*H:035 Using memory-copy operations like that is usually inconvient, so we
118 * have the following helper macros which read and write a specific type (often
121 * This reads into a variable of the given type then returns that. */
122 #define lgread(cpu, addr, type) \
123 ({ type _v; __lgread((cpu), &_v, (addr), sizeof(_v)); _v; })
125 /* This checks that the variable is of the given type, then writes it out. */
126 #define lgwrite(cpu, addr, type, val) \
128 typecheck(type, val); \
129 __lgwrite((cpu), (addr), &(val), sizeof(val)); \
131 /* (end of memory access helper routines) :*/
133 int run_guest(struct lg_cpu
*cpu
, unsigned long __user
*user
);
135 /* Helper macros to obtain the first 12 or the last 20 bits, this is only the
136 * first step in the migration to the kernel types. pte_pfn is already defined
138 #define pgd_flags(x) (pgd_val(x) & ~PAGE_MASK)
139 #define pgd_pfn(x) (pgd_val(x) >> PAGE_SHIFT)
140 #define pmd_flags(x) (pmd_val(x) & ~PAGE_MASK)
141 #define pmd_pfn(x) (pmd_val(x) >> PAGE_SHIFT)
143 /* interrupts_and_traps.c: */
144 unsigned int interrupt_pending(struct lg_cpu
*cpu
, bool *more
);
145 void try_deliver_interrupt(struct lg_cpu
*cpu
, unsigned int irq
, bool more
);
146 bool deliver_trap(struct lg_cpu
*cpu
, unsigned int num
);
147 void load_guest_idt_entry(struct lg_cpu
*cpu
, unsigned int i
,
149 void guest_set_stack(struct lg_cpu
*cpu
, u32 seg
, u32 esp
, unsigned int pages
);
150 void pin_stack_pages(struct lg_cpu
*cpu
);
151 void setup_default_idt_entries(struct lguest_ro_state
*state
,
152 const unsigned long *def
);
153 void copy_traps(const struct lg_cpu
*cpu
, struct desc_struct
*idt
,
154 const unsigned long *def
);
155 void guest_set_clockevent(struct lg_cpu
*cpu
, unsigned long delta
);
156 void init_clockdev(struct lg_cpu
*cpu
);
157 bool check_syscall_vector(struct lguest
*lg
);
158 int init_interrupts(void);
159 void free_interrupts(void);
162 void setup_default_gdt_entries(struct lguest_ro_state
*state
);
163 void setup_guest_gdt(struct lg_cpu
*cpu
);
164 void load_guest_gdt_entry(struct lg_cpu
*cpu
, unsigned int i
,
166 void guest_load_tls(struct lg_cpu
*cpu
, unsigned long tls_array
);
167 void copy_gdt(const struct lg_cpu
*cpu
, struct desc_struct
*gdt
);
168 void copy_gdt_tls(const struct lg_cpu
*cpu
, struct desc_struct
*gdt
);
171 int init_guest_pagetable(struct lguest
*lg
);
172 void free_guest_pagetable(struct lguest
*lg
);
173 void guest_new_pagetable(struct lg_cpu
*cpu
, unsigned long pgtable
);
174 void guest_set_pgd(struct lguest
*lg
, unsigned long gpgdir
, u32 i
);
175 #ifdef CONFIG_X86_PAE
176 void guest_set_pmd(struct lguest
*lg
, unsigned long gpgdir
, u32 i
);
178 void guest_pagetable_clear_all(struct lg_cpu
*cpu
);
179 void guest_pagetable_flush_user(struct lg_cpu
*cpu
);
180 void guest_set_pte(struct lg_cpu
*cpu
, unsigned long gpgdir
,
181 unsigned long vaddr
, pte_t val
);
182 void map_switcher_in_guest(struct lg_cpu
*cpu
, struct lguest_pages
*pages
);
183 bool demand_page(struct lg_cpu
*cpu
, unsigned long cr2
, int errcode
);
184 void pin_page(struct lg_cpu
*cpu
, unsigned long vaddr
);
185 unsigned long guest_pa(struct lg_cpu
*cpu
, unsigned long vaddr
);
186 void page_table_guest_data_init(struct lg_cpu
*cpu
);
189 void lguest_arch_host_init(void);
190 void lguest_arch_host_fini(void);
191 void lguest_arch_run_guest(struct lg_cpu
*cpu
);
192 void lguest_arch_handle_trap(struct lg_cpu
*cpu
);
193 int lguest_arch_init_hypercalls(struct lg_cpu
*cpu
);
194 int lguest_arch_do_hcall(struct lg_cpu
*cpu
, struct hcall_args
*args
);
195 void lguest_arch_setup_regs(struct lg_cpu
*cpu
, unsigned long start
);
197 /* <arch>/switcher.S: */
198 extern char start_switcher_text
[], end_switcher_text
[], switch_to_guest
[];
201 int lguest_device_init(void);
202 void lguest_device_remove(void);
205 void do_hypercalls(struct lg_cpu
*cpu
);
206 void write_timestamp(struct lg_cpu
*cpu
);
209 * Let's step aside for the moment, to study one important routine that's used
210 * widely in the Host code.
212 * There are many cases where the Guest can do something invalid, like pass crap
213 * to a hypercall. Since only the Guest kernel can make hypercalls, it's quite
214 * acceptable to simply terminate the Guest and give the Launcher a nicely
215 * formatted reason. It's also simpler for the Guest itself, which doesn't
216 * need to check most hypercalls for "success"; if you're still running, it
219 * Once this is called, the Guest will never run again, so most Host code can
220 * call this then continue as if nothing had happened. This means many
221 * functions don't have to explicitly return an error code, which keeps the
224 * It also means that this can be called more than once: only the first one is
225 * remembered. The only trick is that we still need to kill the Guest even if
226 * we can't allocate memory to store the reason. Linux has a neat way of
227 * packing error codes into invalid pointers, so we use that here.
229 * Like any macro which uses an "if", it is safely wrapped in a run-once "do {
232 #define kill_guest(cpu, fmt...) \
234 if (!(cpu)->lg->dead) { \
235 (cpu)->lg->dead = kasprintf(GFP_ATOMIC, fmt); \
236 if (!(cpu)->lg->dead) \
237 (cpu)->lg->dead = ERR_PTR(-ENOMEM); \
240 /* (End of aside) :*/
242 #endif /* __ASSEMBLY__ */
243 #endif /* _LGUEST_H */