diff options
Diffstat (limited to 'kernel/drivers/lguest/lg.h')
| -rw-r--r-- | kernel/drivers/lguest/lg.h | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/kernel/drivers/lguest/lg.h b/kernel/drivers/lguest/lg.h new file mode 100644 index 000000000..ac8ad0461 --- /dev/null +++ b/kernel/drivers/lguest/lg.h @@ -0,0 +1,258 @@ +#ifndef _LGUEST_H +#define _LGUEST_H + +#ifndef __ASSEMBLY__ +#include <linux/types.h> +#include <linux/init.h> +#include <linux/stringify.h> +#include <linux/lguest.h> +#include <linux/lguest_launcher.h> +#include <linux/wait.h> +#include <linux/hrtimer.h> +#include <linux/err.h> +#include <linux/slab.h> + +#include <asm/lguest.h> + +struct pgdir { + unsigned long gpgdir; + bool switcher_mapped; + int last_host_cpu; + pgd_t *pgdir; +}; + +/* We have two pages shared with guests, per cpu. */ +struct lguest_pages { + /* This is the stack page mapped rw in guest */ + char spare[PAGE_SIZE - sizeof(struct lguest_regs)]; + struct lguest_regs regs; + + /* This is the host state & guest descriptor page, ro in guest */ + struct lguest_ro_state state; +} __attribute__((aligned(PAGE_SIZE))); + +#define CHANGED_IDT 1 +#define CHANGED_GDT 2 +#define CHANGED_GDT_TLS 4 /* Actually a subset of CHANGED_GDT */ +#define CHANGED_ALL 3 + +struct lg_cpu { + unsigned int id; + struct lguest *lg; + struct task_struct *tsk; + struct mm_struct *mm; /* == tsk->mm, but that becomes NULL on exit */ + + u32 cr2; + int ts; + u32 esp1; + u16 ss1; + + /* Bitmap of what has changed: see CHANGED_* above. */ + int changed; + + /* Pending operation. */ + struct lguest_pending pending; + + unsigned long *reg_read; /* register from LHREQ_GETREG */ + + /* At end of a page shared mapped over lguest_pages in guest. */ + unsigned long regs_page; + struct lguest_regs *regs; + + struct lguest_pages *last_pages; + + /* Initialization mode: linear map everything. */ + bool linear_pages; + int cpu_pgd; /* Which pgd this cpu is currently using */ + + /* If a hypercall was asked for, this points to the arguments. */ + struct hcall_args *hcall; + u32 next_hcall; + + /* Virtual clock device */ + struct hrtimer hrt; + + /* Did the Guest tell us to halt? */ + int halted; + + /* Pending virtual interrupts */ + DECLARE_BITMAP(irqs_pending, LGUEST_IRQS); + + struct lg_cpu_arch arch; +}; + +/* The private info the thread maintains about the guest. */ +struct lguest { + struct lguest_data __user *lguest_data; + struct lg_cpu cpus[NR_CPUS]; + unsigned int nr_cpus; + + /* Valid guest memory pages must be < this. */ + u32 pfn_limit; + + /* Device memory is >= pfn_limit and < device_limit. */ + u32 device_limit; + + /* + * This provides the offset to the base of guest-physical memory in the + * Launcher. + */ + void __user *mem_base; + unsigned long kernel_address; + + struct pgdir pgdirs[4]; + + unsigned long noirq_iret; + + unsigned int stack_pages; + u32 tsc_khz; + + /* Dead? */ + const char *dead; +}; + +extern struct mutex lguest_lock; + +/* core.c: */ +bool lguest_address_ok(const struct lguest *lg, + unsigned long addr, unsigned long len); +void __lgread(struct lg_cpu *, void *, unsigned long, unsigned); +void __lgwrite(struct lg_cpu *, unsigned long, const void *, unsigned); +extern struct page **lg_switcher_pages; + +/*H:035 + * Using memory-copy operations like that is usually inconvient, so we + * have the following helper macros which read and write a specific type (often + * an unsigned long). + * + * This reads into a variable of the given type then returns that. + */ +#define lgread(cpu, addr, type) \ + ({ type _v; __lgread((cpu), &_v, (addr), sizeof(_v)); _v; }) + +/* This checks that the variable is of the given type, then writes it out. */ +#define lgwrite(cpu, addr, type, val) \ + do { \ + typecheck(type, val); \ + __lgwrite((cpu), (addr), &(val), sizeof(val)); \ + } while(0) +/* (end of memory access helper routines) :*/ + +int run_guest(struct lg_cpu *cpu, unsigned long __user *user); + +/* + * Helper macros to obtain the first 12 or the last 20 bits, this is only the + * first step in the migration to the kernel types. pte_pfn is already defined + * in the kernel. + */ +#define pgd_flags(x) (pgd_val(x) & ~PAGE_MASK) +#define pgd_pfn(x) (pgd_val(x) >> PAGE_SHIFT) +#define pmd_flags(x) (pmd_val(x) & ~PAGE_MASK) +#define pmd_pfn(x) (pmd_val(x) >> PAGE_SHIFT) + +/* interrupts_and_traps.c: */ +unsigned int interrupt_pending(struct lg_cpu *cpu, bool *more); +void try_deliver_interrupt(struct lg_cpu *cpu, unsigned int irq, bool more); +void set_interrupt(struct lg_cpu *cpu, unsigned int irq); +bool deliver_trap(struct lg_cpu *cpu, unsigned int num); +void load_guest_idt_entry(struct lg_cpu *cpu, unsigned int i, + u32 low, u32 hi); +void guest_set_stack(struct lg_cpu *cpu, u32 seg, u32 esp, unsigned int pages); +void pin_stack_pages(struct lg_cpu *cpu); +void setup_default_idt_entries(struct lguest_ro_state *state, + const unsigned long *def); +void copy_traps(const struct lg_cpu *cpu, struct desc_struct *idt, + const unsigned long *def); +void guest_set_clockevent(struct lg_cpu *cpu, unsigned long delta); +bool send_notify_to_eventfd(struct lg_cpu *cpu); +void init_clockdev(struct lg_cpu *cpu); +bool check_syscall_vector(struct lguest *lg); +int init_interrupts(void); +void free_interrupts(void); + +/* segments.c: */ +void setup_default_gdt_entries(struct lguest_ro_state *state); +void setup_guest_gdt(struct lg_cpu *cpu); +void load_guest_gdt_entry(struct lg_cpu *cpu, unsigned int i, + u32 low, u32 hi); +void guest_load_tls(struct lg_cpu *cpu, unsigned long tls_array); +void copy_gdt(const struct lg_cpu *cpu, struct desc_struct *gdt); +void copy_gdt_tls(const struct lg_cpu *cpu, struct desc_struct *gdt); + +/* page_tables.c: */ +int init_guest_pagetable(struct lguest *lg); +void free_guest_pagetable(struct lguest *lg); +void guest_new_pagetable(struct lg_cpu *cpu, unsigned long pgtable); +void guest_set_pgd(struct lguest *lg, unsigned long gpgdir, u32 i); +#ifdef CONFIG_X86_PAE +void guest_set_pmd(struct lguest *lg, unsigned long gpgdir, u32 i); +#endif +void guest_pagetable_clear_all(struct lg_cpu *cpu); +void guest_pagetable_flush_user(struct lg_cpu *cpu); +void guest_set_pte(struct lg_cpu *cpu, unsigned long gpgdir, + unsigned long vaddr, pte_t val); +void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages); +bool demand_page(struct lg_cpu *cpu, unsigned long cr2, int errcode, + unsigned long *iomem); +void pin_page(struct lg_cpu *cpu, unsigned long vaddr); +bool __guest_pa(struct lg_cpu *cpu, unsigned long vaddr, unsigned long *paddr); +unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr); +void page_table_guest_data_init(struct lg_cpu *cpu); + +/* <arch>/core.c: */ +void lguest_arch_host_init(void); +void lguest_arch_host_fini(void); +void lguest_arch_run_guest(struct lg_cpu *cpu); +void lguest_arch_handle_trap(struct lg_cpu *cpu); +int lguest_arch_init_hypercalls(struct lg_cpu *cpu); +int lguest_arch_do_hcall(struct lg_cpu *cpu, struct hcall_args *args); +void lguest_arch_setup_regs(struct lg_cpu *cpu, unsigned long start); +unsigned long *lguest_arch_regptr(struct lg_cpu *cpu, size_t reg_off, bool any); + +/* <arch>/switcher.S: */ +extern char start_switcher_text[], end_switcher_text[], switch_to_guest[]; + +/* lguest_user.c: */ +int lguest_device_init(void); +void lguest_device_remove(void); + +/* hypercalls.c: */ +void do_hypercalls(struct lg_cpu *cpu); +void write_timestamp(struct lg_cpu *cpu); + +/*L:035 + * Let's step aside for the moment, to study one important routine that's used + * widely in the Host code. + * + * There are many cases where the Guest can do something invalid, like pass crap + * to a hypercall. Since only the Guest kernel can make hypercalls, it's quite + * acceptable to simply terminate the Guest and give the Launcher a nicely + * formatted reason. It's also simpler for the Guest itself, which doesn't + * need to check most hypercalls for "success"; if you're still running, it + * succeeded. + * + * Once this is called, the Guest will never run again, so most Host code can + * call this then continue as if nothing had happened. This means many + * functions don't have to explicitly return an error code, which keeps the + * code simple. + * + * It also means that this can be called more than once: only the first one is + * remembered. The only trick is that we still need to kill the Guest even if + * we can't allocate memory to store the reason. Linux has a neat way of + * packing error codes into invalid pointers, so we use that here. + * + * Like any macro which uses an "if", it is safely wrapped in a run-once "do { + * } while(0)". + */ +#define kill_guest(cpu, fmt...) \ +do { \ + if (!(cpu)->lg->dead) { \ + (cpu)->lg->dead = kasprintf(GFP_ATOMIC, fmt); \ + if (!(cpu)->lg->dead) \ + (cpu)->lg->dead = ERR_PTR(-ENOMEM); \ + } \ +} while(0) +/* (End of aside) :*/ + +#endif /* __ASSEMBLY__ */ +#endif /* _LGUEST_H */ |