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/err.h>
12 #include <asm/semaphore.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 */
47 /* If a hypercall was asked for, this points to the arguments. */
48 struct hcall_args
*hcall
;
51 /* Virtual clock device */
54 /* Pending virtual interrupts */
55 DECLARE_BITMAP(irqs_pending
, LGUEST_IRQS
);
58 /* The private info the thread maintains about the guest. */
61 /* At end of a page shared mapped over lguest_pages in guest. */
62 unsigned long regs_page
;
63 struct lguest_regs
*regs
;
64 struct lguest_data __user
*lguest_data
;
65 struct task_struct
*tsk
;
66 struct mm_struct
*mm
; /* == tsk->mm, but that becomes NULL on exit */
67 struct lg_cpu cpus
[NR_CPUS
];
71 /* This provides the offset to the base of guest-physical
72 * memory in the Launcher. */
73 void __user
*mem_base
;
74 unsigned long kernel_address
;
81 /* Do we need to stop what we're doing and return to userspace? */
83 wait_queue_head_t break_wq
;
85 /* Bitmap of what has changed: see CHANGED_* above. */
87 struct lguest_pages
*last_pages
;
89 /* We keep a small number of these. */
91 struct pgdir pgdirs
[4];
93 unsigned long noirq_start
, noirq_end
;
94 unsigned long pending_notify
; /* pfn from LHCALL_NOTIFY */
96 unsigned int stack_pages
;
102 struct lguest_arch arch
;
105 extern struct mutex lguest_lock
;
108 int lguest_address_ok(const struct lguest
*lg
,
109 unsigned long addr
, unsigned long len
);
110 void __lgread(struct lguest
*, void *, unsigned long, unsigned);
111 void __lgwrite(struct lguest
*, unsigned long, const void *, unsigned);
113 /*H:035 Using memory-copy operations like that is usually inconvient, so we
114 * have the following helper macros which read and write a specific type (often
117 * This reads into a variable of the given type then returns that. */
118 #define lgread(lg, addr, type) \
119 ({ type _v; __lgread((lg), &_v, (addr), sizeof(_v)); _v; })
121 /* This checks that the variable is of the given type, then writes it out. */
122 #define lgwrite(lg, addr, type, val) \
124 typecheck(type, val); \
125 __lgwrite((lg), (addr), &(val), sizeof(val)); \
127 /* (end of memory access helper routines) :*/
129 int run_guest(struct lg_cpu
*cpu
, unsigned long __user
*user
);
131 /* Helper macros to obtain the first 12 or the last 20 bits, this is only the
132 * first step in the migration to the kernel types. pte_pfn is already defined
134 #define pgd_flags(x) (pgd_val(x) & ~PAGE_MASK)
135 #define pte_flags(x) (pte_val(x) & ~PAGE_MASK)
136 #define pgd_pfn(x) (pgd_val(x) >> PAGE_SHIFT)
138 /* interrupts_and_traps.c: */
139 void maybe_do_interrupt(struct lg_cpu
*cpu
);
140 int deliver_trap(struct lg_cpu
*cpu
, unsigned int num
);
141 void load_guest_idt_entry(struct lguest
*lg
, unsigned int i
, u32 low
, u32 hi
);
142 void guest_set_stack(struct lguest
*lg
, u32 seg
, u32 esp
, unsigned int pages
);
143 void pin_stack_pages(struct lguest
*lg
);
144 void setup_default_idt_entries(struct lguest_ro_state
*state
,
145 const unsigned long *def
);
146 void copy_traps(const struct lguest
*lg
, struct desc_struct
*idt
,
147 const unsigned long *def
);
148 void guest_set_clockevent(struct lg_cpu
*cpu
, unsigned long delta
);
149 void init_clockdev(struct lg_cpu
*cpu
);
150 bool check_syscall_vector(struct lguest
*lg
);
151 int init_interrupts(void);
152 void free_interrupts(void);
155 void setup_default_gdt_entries(struct lguest_ro_state
*state
);
156 void setup_guest_gdt(struct lguest
*lg
);
157 void load_guest_gdt(struct lguest
*lg
, unsigned long table
, u32 num
);
158 void guest_load_tls(struct lguest
*lg
, unsigned long tls_array
);
159 void copy_gdt(const struct lguest
*lg
, struct desc_struct
*gdt
);
160 void copy_gdt_tls(const struct lguest
*lg
, struct desc_struct
*gdt
);
163 int init_guest_pagetable(struct lguest
*lg
, unsigned long pgtable
);
164 void free_guest_pagetable(struct lguest
*lg
);
165 void guest_new_pagetable(struct lguest
*lg
, unsigned long pgtable
);
166 void guest_set_pmd(struct lguest
*lg
, unsigned long gpgdir
, u32 i
);
167 void guest_pagetable_clear_all(struct lguest
*lg
);
168 void guest_pagetable_flush_user(struct lguest
*lg
);
169 void guest_set_pte(struct lguest
*lg
, unsigned long gpgdir
,
170 unsigned long vaddr
, pte_t val
);
171 void map_switcher_in_guest(struct lg_cpu
*cpu
, struct lguest_pages
*pages
);
172 int demand_page(struct lguest
*info
, unsigned long cr2
, int errcode
);
173 void pin_page(struct lguest
*lg
, unsigned long vaddr
);
174 unsigned long guest_pa(struct lguest
*lg
, unsigned long vaddr
);
175 void page_table_guest_data_init(struct lguest
*lg
);
178 void lguest_arch_host_init(void);
179 void lguest_arch_host_fini(void);
180 void lguest_arch_run_guest(struct lg_cpu
*cpu
);
181 void lguest_arch_handle_trap(struct lg_cpu
*cpu
);
182 int lguest_arch_init_hypercalls(struct lg_cpu
*cpu
);
183 int lguest_arch_do_hcall(struct lg_cpu
*cpu
, struct hcall_args
*args
);
184 void lguest_arch_setup_regs(struct lguest
*lg
, unsigned long start
);
186 /* <arch>/switcher.S: */
187 extern char start_switcher_text
[], end_switcher_text
[], switch_to_guest
[];
190 int lguest_device_init(void);
191 void lguest_device_remove(void);
194 void do_hypercalls(struct lg_cpu
*cpu
);
195 void write_timestamp(struct lguest
*lg
);
198 * Let's step aside for the moment, to study one important routine that's used
199 * widely in the Host code.
201 * There are many cases where the Guest can do something invalid, like pass crap
202 * to a hypercall. Since only the Guest kernel can make hypercalls, it's quite
203 * acceptable to simply terminate the Guest and give the Launcher a nicely
204 * formatted reason. It's also simpler for the Guest itself, which doesn't
205 * need to check most hypercalls for "success"; if you're still running, it
208 * Once this is called, the Guest will never run again, so most Host code can
209 * call this then continue as if nothing had happened. This means many
210 * functions don't have to explicitly return an error code, which keeps the
213 * It also means that this can be called more than once: only the first one is
214 * remembered. The only trick is that we still need to kill the Guest even if
215 * we can't allocate memory to store the reason. Linux has a neat way of
216 * packing error codes into invalid pointers, so we use that here.
218 * Like any macro which uses an "if", it is safely wrapped in a run-once "do {
221 #define kill_guest(lg, fmt...) \
224 (lg)->dead = kasprintf(GFP_ATOMIC, fmt); \
226 (lg)->dead = ERR_PTR(-ENOMEM); \
229 /* (End of aside) :*/
231 #endif /* __ASSEMBLY__ */
232 #endif /* _LGUEST_H */