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