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 17void free_pagetables(void); 18int init_pagetables(struct page **switcher_page, unsigned int pages); 19 20struct pgdir { 21 unsigned long gpgdir; 22 pgd_t *pgdir; 23}; 24 25/* We have two pages shared with guests, per cpu. */ 26struct 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 40struct 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 int cpu_pgd; /* Which pgd this cpu is currently using */ 63 64 /* If a hypercall was asked for, this points to the arguments. */ 65 struct hcall_args *hcall; 66 u32 next_hcall; 67 68 /* Virtual clock device */ 69 struct hrtimer hrt; 70 71 /* Did the Guest tell us to halt? */ 72 int halted; 73 74 /* Pending virtual interrupts */ 75 DECLARE_BITMAP(irqs_pending, LGUEST_IRQS); 76 77 struct lg_cpu_arch arch; 78}; 79 80struct lg_eventfd { 81 unsigned long addr; 82 struct eventfd_ctx *event; 83}; 84 85struct lg_eventfd_map { 86 unsigned int num; 87 struct lg_eventfd map[]; 88}; 89 90/* The private info the thread maintains about the guest. */ 91struct lguest { 92 struct lguest_data __user *lguest_data; 93 struct lg_cpu cpus[NR_CPUS]; 94 unsigned int nr_cpus; 95 96 u32 pfn_limit; 97 98 /* 99 * This provides the offset to the base of guest-physical memory in the 100 * Launcher. 101 */ 102 void __user *mem_base; 103 unsigned long kernel_address; 104 105 struct pgdir pgdirs[4]; 106 107 unsigned long noirq_start, noirq_end; 108 109 unsigned int stack_pages; 110 u32 tsc_khz; 111 112 struct lg_eventfd_map *eventfds; 113 114 /* Dead? */ 115 const char *dead; 116}; 117 118extern struct mutex lguest_lock; 119 120/* core.c: */ 121bool lguest_address_ok(const struct lguest *lg, 122 unsigned long addr, unsigned long len); 123void __lgread(struct lg_cpu *, void *, unsigned long, unsigned); 124void __lgwrite(struct lg_cpu *, unsigned long, const void *, unsigned); 125 126/*H:035 127 * Using memory-copy operations like that is usually inconvient, so we 128 * have the following helper macros which read and write a specific type (often 129 * an unsigned long). 130 * 131 * This reads into a variable of the given type then returns that. 132 */ 133#define lgread(cpu, addr, type) \ 134 ({ type _v; __lgread((cpu), &_v, (addr), sizeof(_v)); _v; }) 135 136/* This checks that the variable is of the given type, then writes it out. */ 137#define lgwrite(cpu, addr, type, val) \ 138 do { \ 139 typecheck(type, val); \ 140 __lgwrite((cpu), (addr), &(val), sizeof(val)); \ 141 } while(0) 142/* (end of memory access helper routines) :*/ 143 144int run_guest(struct lg_cpu *cpu, unsigned long __user *user); 145 146/* 147 * Helper macros to obtain the first 12 or the last 20 bits, this is only the 148 * first step in the migration to the kernel types. pte_pfn is already defined 149 * in the kernel. 150 */ 151#define pgd_flags(x) (pgd_val(x) & ~PAGE_MASK) 152#define pgd_pfn(x) (pgd_val(x) >> PAGE_SHIFT) 153#define pmd_flags(x) (pmd_val(x) & ~PAGE_MASK) 154#define pmd_pfn(x) (pmd_val(x) >> PAGE_SHIFT) 155 156/* interrupts_and_traps.c: */ 157unsigned int interrupt_pending(struct lg_cpu *cpu, bool *more); 158void try_deliver_interrupt(struct lg_cpu *cpu, unsigned int irq, bool more); 159void set_interrupt(struct lg_cpu *cpu, unsigned int irq); 160bool deliver_trap(struct lg_cpu *cpu, unsigned int num); 161void load_guest_idt_entry(struct lg_cpu *cpu, unsigned int i, 162 u32 low, u32 hi); 163void guest_set_stack(struct lg_cpu *cpu, u32 seg, u32 esp, unsigned int pages); 164void pin_stack_pages(struct lg_cpu *cpu); 165void setup_default_idt_entries(struct lguest_ro_state *state, 166 const unsigned long *def); 167void copy_traps(const struct lg_cpu *cpu, struct desc_struct *idt, 168 const unsigned long *def); 169void guest_set_clockevent(struct lg_cpu *cpu, unsigned long delta); 170bool send_notify_to_eventfd(struct lg_cpu *cpu); 171void init_clockdev(struct lg_cpu *cpu); 172bool check_syscall_vector(struct lguest *lg); 173int init_interrupts(void); 174void free_interrupts(void); 175 176/* segments.c: */ 177void setup_default_gdt_entries(struct lguest_ro_state *state); 178void setup_guest_gdt(struct lg_cpu *cpu); 179void load_guest_gdt_entry(struct lg_cpu *cpu, unsigned int i, 180 u32 low, u32 hi); 181void guest_load_tls(struct lg_cpu *cpu, unsigned long tls_array); 182void copy_gdt(const struct lg_cpu *cpu, struct desc_struct *gdt); 183void copy_gdt_tls(const struct lg_cpu *cpu, struct desc_struct *gdt); 184 185/* page_tables.c: */ 186int init_guest_pagetable(struct lguest *lg); 187void free_guest_pagetable(struct lguest *lg); 188void guest_new_pagetable(struct lg_cpu *cpu, unsigned long pgtable); 189void guest_set_pgd(struct lguest *lg, unsigned long gpgdir, u32 i); 190#ifdef CONFIG_X86_PAE 191void guest_set_pmd(struct lguest *lg, unsigned long gpgdir, u32 i); 192#endif 193void guest_pagetable_clear_all(struct lg_cpu *cpu); 194void guest_pagetable_flush_user(struct lg_cpu *cpu); 195void guest_set_pte(struct lg_cpu *cpu, unsigned long gpgdir, 196 unsigned long vaddr, pte_t val); 197void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages); 198bool demand_page(struct lg_cpu *cpu, unsigned long cr2, int errcode); 199void pin_page(struct lg_cpu *cpu, unsigned long vaddr); 200unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr); 201void page_table_guest_data_init(struct lg_cpu *cpu); 202 203/* <arch>/core.c: */ 204void lguest_arch_host_init(void); 205void lguest_arch_host_fini(void); 206void lguest_arch_run_guest(struct lg_cpu *cpu); 207void lguest_arch_handle_trap(struct lg_cpu *cpu); 208int lguest_arch_init_hypercalls(struct lg_cpu *cpu); 209int lguest_arch_do_hcall(struct lg_cpu *cpu, struct hcall_args *args); 210void lguest_arch_setup_regs(struct lg_cpu *cpu, unsigned long start); 211 212/* <arch>/switcher.S: */ 213extern char start_switcher_text[], end_switcher_text[], switch_to_guest[]; 214 215/* lguest_user.c: */ 216int lguest_device_init(void); 217void lguest_device_remove(void); 218 219/* hypercalls.c: */ 220void do_hypercalls(struct lg_cpu *cpu); 221void 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...) \ 248do { \ 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