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 17 void free_pagetables(void); 18 int init_pagetables(struct page **switcher_page, unsigned int pages); 19 20 struct pgdir { 21 unsigned long gpgdir; 22 pgd_t *pgdir; 23 }; 24 25 /* We have two pages shared with guests, per cpu. */ 26 struct 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 40 struct 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 82 struct lg_eventfd { 83 unsigned long addr; 84 struct eventfd_ctx *event; 85 }; 86 87 struct lg_eventfd_map { 88 unsigned int num; 89 struct lg_eventfd map[]; 90 }; 91 92 /* The private info the thread maintains about the guest. */ 93 struct 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 }; 119 120 extern struct mutex lguest_lock; 121 122 /* core.c: */ 123 bool lguest_address_ok(const struct lguest *lg, 124 unsigned long addr, unsigned long len); 125 void __lgread(struct lg_cpu *, void *, unsigned long, unsigned); 126 void __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) :*/ 145 146 int 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: */ 159 unsigned int interrupt_pending(struct lg_cpu *cpu, bool *more); 160 void try_deliver_interrupt(struct lg_cpu *cpu, unsigned int irq, bool more); 161 void set_interrupt(struct lg_cpu *cpu, unsigned int irq); 162 bool deliver_trap(struct lg_cpu *cpu, unsigned int num); 163 void load_guest_idt_entry(struct lg_cpu *cpu, unsigned int i, 164 u32 low, u32 hi); 165 void guest_set_stack(struct lg_cpu *cpu, u32 seg, u32 esp, unsigned int pages); 166 void pin_stack_pages(struct lg_cpu *cpu); 167 void setup_default_idt_entries(struct lguest_ro_state *state, 168 const unsigned long *def); 169 void copy_traps(const struct lg_cpu *cpu, struct desc_struct *idt, 170 const unsigned long *def); 171 void guest_set_clockevent(struct lg_cpu *cpu, unsigned long delta); 172 bool send_notify_to_eventfd(struct lg_cpu *cpu); 173 void init_clockdev(struct lg_cpu *cpu); 174 bool check_syscall_vector(struct lguest *lg); 175 int init_interrupts(void); 176 void free_interrupts(void); 177 178 /* segments.c: */ 179 void setup_default_gdt_entries(struct lguest_ro_state *state); 180 void setup_guest_gdt(struct lg_cpu *cpu); 181 void load_guest_gdt_entry(struct lg_cpu *cpu, unsigned int i, 182 u32 low, u32 hi); 183 void guest_load_tls(struct lg_cpu *cpu, unsigned long tls_array); 184 void copy_gdt(const struct lg_cpu *cpu, struct desc_struct *gdt); 185 void copy_gdt_tls(const struct lg_cpu *cpu, struct desc_struct *gdt); 186 187 /* page_tables.c: */ 188 int init_guest_pagetable(struct lguest *lg); 189 void free_guest_pagetable(struct lguest *lg); 190 void guest_new_pagetable(struct lg_cpu *cpu, unsigned long pgtable); 191 void guest_set_pgd(struct lguest *lg, unsigned long gpgdir, u32 i); 192 #ifdef CONFIG_X86_PAE 193 void guest_set_pmd(struct lguest *lg, unsigned long gpgdir, u32 i); 194 #endif 195 void guest_pagetable_clear_all(struct lg_cpu *cpu); 196 void guest_pagetable_flush_user(struct lg_cpu *cpu); 197 void guest_set_pte(struct lg_cpu *cpu, unsigned long gpgdir, 198 unsigned long vaddr, pte_t val); 199 void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages); 200 bool demand_page(struct lg_cpu *cpu, unsigned long cr2, int errcode); 201 void pin_page(struct lg_cpu *cpu, unsigned long vaddr); 202 unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr); 203 void page_table_guest_data_init(struct lg_cpu *cpu); 204 205 /* <arch>/core.c: */ 206 void lguest_arch_host_init(void); 207 void lguest_arch_host_fini(void); 208 void lguest_arch_run_guest(struct lg_cpu *cpu); 209 void lguest_arch_handle_trap(struct lg_cpu *cpu); 210 int lguest_arch_init_hypercalls(struct lg_cpu *cpu); 211 int lguest_arch_do_hcall(struct lg_cpu *cpu, struct hcall_args *args); 212 void lguest_arch_setup_regs(struct lg_cpu *cpu, unsigned long start); 213 214 /* <arch>/switcher.S: */ 215 extern char start_switcher_text[], end_switcher_text[], switch_to_guest[]; 216 217 /* lguest_user.c: */ 218 int lguest_device_init(void); 219 void lguest_device_remove(void); 220 221 /* hypercalls.c: */ 222 void do_hypercalls(struct lg_cpu *cpu); 223 void 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...) \ 250 do { \ 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 */ 261