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 */
41 /* The private info the thread maintains about the guest. */
44 /* At end of a page shared mapped over lguest_pages in guest. */
45 unsigned long regs_page;
46 struct lguest_regs *regs;
47 struct lguest_data __user *lguest_data;
48 struct task_struct *tsk;
49 struct mm_struct *mm; /* == tsk->mm, but that becomes NULL on exit */
51 /* This provides the offset to the base of guest-physical
52 * memory in the Launcher. */
53 void __user *mem_base;
54 unsigned long kernel_address;
62 /* If a hypercall was asked for, this points to the arguments. */
63 struct hcall_args *hcall;
65 /* Do we need to stop what we're doing and return to userspace? */
67 wait_queue_head_t break_wq;
69 /* Bitmap of what has changed: see CHANGED_* above. */
71 struct lguest_pages *last_pages;
73 /* We keep a small number of these. */
75 struct pgdir pgdirs[4];
77 /* Cached wakeup: we hold a reference to this task. */
78 struct task_struct *wake;
80 unsigned long noirq_start, noirq_end;
81 unsigned long pending_notify; /* pfn from LHCALL_NOTIFY */
83 unsigned int stack_pages;
89 struct lguest_arch arch;
91 /* Virtual clock device */
94 /* Pending virtual interrupts */
95 DECLARE_BITMAP(irqs_pending, LGUEST_IRQS);
98 extern struct mutex lguest_lock;
101 u32 lgread_u32(struct lguest *lg, unsigned long addr);
102 void lgwrite_u32(struct lguest *lg, unsigned long addr, u32 val);
103 void lgread(struct lguest *lg, void *buf, unsigned long addr, unsigned len);
104 void lgwrite(struct lguest *lg, unsigned long, const void *buf, unsigned len);
105 int lguest_address_ok(const struct lguest *lg,
106 unsigned long addr, unsigned long len);
107 int run_guest(struct lguest *lg, unsigned long __user *user);
109 /* Helper macros to obtain the first 12 or the last 20 bits, this is only the
110 * first step in the migration to the kernel types. pte_pfn is already defined
112 #define pgd_flags(x) (pgd_val(x) & ~PAGE_MASK)
113 #define pte_flags(x) (pte_val(x) & ~PAGE_MASK)
114 #define pgd_pfn(x) (pgd_val(x) >> PAGE_SHIFT)
116 /* interrupts_and_traps.c: */
117 void maybe_do_interrupt(struct lguest *lg);
118 int deliver_trap(struct lguest *lg, unsigned int num);
119 void load_guest_idt_entry(struct lguest *lg, unsigned int i, u32 low, u32 hi);
120 void guest_set_stack(struct lguest *lg, u32 seg, u32 esp, unsigned int pages);
121 void pin_stack_pages(struct lguest *lg);
122 void setup_default_idt_entries(struct lguest_ro_state *state,
123 const unsigned long *def);
124 void copy_traps(const struct lguest *lg, struct desc_struct *idt,
125 const unsigned long *def);
126 void guest_set_clockevent(struct lguest *lg, unsigned long delta);
127 void init_clockdev(struct lguest *lg);
128 bool check_syscall_vector(struct lguest *lg);
129 int init_interrupts(void);
130 void free_interrupts(void);
133 void setup_default_gdt_entries(struct lguest_ro_state *state);
134 void setup_guest_gdt(struct lguest *lg);
135 void load_guest_gdt(struct lguest *lg, unsigned long table, u32 num);
136 void guest_load_tls(struct lguest *lg, unsigned long tls_array);
137 void copy_gdt(const struct lguest *lg, struct desc_struct *gdt);
138 void copy_gdt_tls(const struct lguest *lg, struct desc_struct *gdt);
141 int init_guest_pagetable(struct lguest *lg, unsigned long pgtable);
142 void free_guest_pagetable(struct lguest *lg);
143 void guest_new_pagetable(struct lguest *lg, unsigned long pgtable);
144 void guest_set_pmd(struct lguest *lg, unsigned long gpgdir, u32 i);
145 void guest_pagetable_clear_all(struct lguest *lg);
146 void guest_pagetable_flush_user(struct lguest *lg);
147 void guest_set_pte(struct lguest *lg, unsigned long gpgdir,
148 unsigned long vaddr, pte_t val);
149 void map_switcher_in_guest(struct lguest *lg, struct lguest_pages *pages);
150 int demand_page(struct lguest *info, unsigned long cr2, int errcode);
151 void pin_page(struct lguest *lg, unsigned long vaddr);
152 unsigned long guest_pa(struct lguest *lg, unsigned long vaddr);
153 void page_table_guest_data_init(struct lguest *lg);
156 void lguest_arch_host_init(void);
157 void lguest_arch_host_fini(void);
158 void lguest_arch_run_guest(struct lguest *lg);
159 void lguest_arch_handle_trap(struct lguest *lg);
160 int lguest_arch_init_hypercalls(struct lguest *lg);
161 int lguest_arch_do_hcall(struct lguest *lg, struct hcall_args *args);
162 void lguest_arch_setup_regs(struct lguest *lg, unsigned long start);
164 /* <arch>/switcher.S: */
165 extern char start_switcher_text[], end_switcher_text[], switch_to_guest[];
168 int lguest_device_init(void);
169 void lguest_device_remove(void);
172 void do_hypercalls(struct lguest *lg);
173 void write_timestamp(struct lguest *lg);
176 * Let's step aside for the moment, to study one important routine that's used
177 * widely in the Host code.
179 * There are many cases where the Guest does something invalid, like pass crap
180 * to a hypercall. Since only the Guest kernel can make hypercalls, it's quite
181 * acceptable to simply terminate the Guest and give the Launcher a nicely
182 * formatted reason. It's also simpler for the Guest itself, which doesn't
183 * need to check most hypercalls for "success"; if you're still running, it
186 * Once this is called, the Guest will never run again, so most Host code can
187 * call this then continue as if nothing had happened. This means many
188 * functions don't have to explicitly return an error code, which keeps the
191 * It also means that this can be called more than once: only the first one is
192 * remembered. The only trick is that we still need to kill the Guest even if
193 * we can't allocate memory to store the reason. Linux has a neat way of
194 * packing error codes into invalid pointers, so we use that here.
196 * Like any macro which uses an "if", it is safely wrapped in a run-once "do {
199 #define kill_guest(lg, fmt...) \
202 (lg)->dead = kasprintf(GFP_ATOMIC, fmt); \
204 (lg)->dead = ERR_PTR(-ENOMEM); \
207 /* (End of aside) :*/
209 #endif /* __ASSEMBLY__ */
210 #endif /* _LGUEST_H */