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#ifndef _LGUEST_H
#define _LGUEST_H
#include <asm/desc.h>
#define GDT_ENTRY_LGUEST_CS 10
#define GDT_ENTRY_LGUEST_DS 11
#define LGUEST_CS (GDT_ENTRY_LGUEST_CS * 8)
#define LGUEST_DS (GDT_ENTRY_LGUEST_DS * 8)
#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <linux/init.h>
#include <linux/stringify.h>
#include <linux/futex.h>
#include <linux/lguest.h>
#include <linux/lguest_launcher.h>
#include <linux/wait.h>
#include <linux/err.h>
#include <asm/semaphore.h>
#include "irq_vectors.h"
#define GUEST_PL 1
struct lguest_regs
{
/* Manually saved part. */
unsigned long ebx, ecx, edx;
unsigned long esi, edi, ebp;
unsigned long gs;
unsigned long eax;
unsigned long fs, ds, es;
unsigned long trapnum, errcode;
/* Trap pushed part */
unsigned long eip;
unsigned long cs;
unsigned long eflags;
unsigned long esp;
unsigned long ss;
};
void free_pagetables(void);
int init_pagetables(struct page **switcher_page, unsigned int pages);
/* Full 4G segment descriptors, suitable for CS and DS. */
#define FULL_EXEC_SEGMENT ((struct desc_struct){0x0000ffff, 0x00cf9b00})
#define FULL_SEGMENT ((struct desc_struct){0x0000ffff, 0x00cf9300})
struct lguest_dma_info
{
struct list_head list;
union futex_key key;
unsigned long dmas;
struct lguest *owner;
u16 next_dma;
u16 num_dmas;
u8 interrupt; /* 0 when not registered */
};
/*H:310 The page-table code owes a great debt of gratitude to Andi Kleen. He
* reviewed the original code which used "u32" for all page table entries, and
* insisted that it would be far clearer with explicit typing. I thought it
* was overkill, but he was right: it is much clearer than it was before.
*
* We have separate types for the Guest's ptes & pgds and the shadow ptes &
* pgds. There's already a Linux type for these (pte_t and pgd_t) but they
* change depending on kernel config options (PAE). */
/* Each entry is identical: lower 12 bits of flags and upper 20 bits for the
* "page frame number" (0 == first physical page, etc). They are different
* types so the compiler will warn us if we mix them improperly. */
typedef union {
struct { unsigned flags:12, pfn:20; };
struct { unsigned long val; } raw;
} spgd_t;
typedef union {
struct { unsigned flags:12, pfn:20; };
struct { unsigned long val; } raw;
} spte_t;
typedef union {
struct { unsigned flags:12, pfn:20; };
struct { unsigned long val; } raw;
} gpgd_t;
typedef union {
struct { unsigned flags:12, pfn:20; };
struct { unsigned long val; } raw;
} gpte_t;
/* We have two convenient macros to convert a "raw" value as handed to us by
* the Guest into the correct Guest PGD or PTE type. */
#define mkgpte(_val) ((gpte_t){.raw.val = _val})
#define mkgpgd(_val) ((gpgd_t){.raw.val = _val})
/*:*/
struct pgdir
{
unsigned long cr3;
spgd_t *pgdir;
};
/* This is a guest-specific page (mapped ro) into the guest. */
struct lguest_ro_state
{
/* Host information we need to restore when we switch back. */
u32 host_cr3;
struct Xgt_desc_struct host_idt_desc;
struct Xgt_desc_struct host_gdt_desc;
u32 host_sp;
/* Fields which are used when guest is running. */
struct Xgt_desc_struct guest_idt_desc;
struct Xgt_desc_struct guest_gdt_desc;
struct i386_hw_tss guest_tss;
struct desc_struct guest_idt[IDT_ENTRIES];
struct desc_struct guest_gdt[GDT_ENTRIES];
};
/* 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
/* The private info the thread maintains about the guest. */
struct lguest
{
/* At end of a page shared mapped over lguest_pages in guest. */
unsigned long regs_page;
struct lguest_regs *regs;
struct lguest_data __user *lguest_data;
struct task_struct *tsk;
struct mm_struct *mm; /* == tsk->mm, but that becomes NULL on exit */
u32 pfn_limit;
/* This provides the offset to the base of guest-physical
* memory in the Launcher. */
void __user *mem_base;
u32 page_offset;
u32 cr2;
int halted;
int ts;
u32 next_hcall;
u32 esp1;
u8 ss1;
/* Do we need to stop what we're doing and return to userspace? */
int break_out;
wait_queue_head_t break_wq;
/* Bitmap of what has changed: see CHANGED_* above. */
int changed;
struct lguest_pages *last_pages;
/* We keep a small number of these. */
u32 pgdidx;
struct pgdir pgdirs[4];
/* Cached wakeup: we hold a reference to this task. */
struct task_struct *wake;
unsigned long noirq_start, noirq_end;
int dma_is_pending;
unsigned long pending_dma; /* struct lguest_dma */
unsigned long pending_key; /* address they're sending to */
unsigned int stack_pages;
u32 tsc_khz;
struct lguest_dma_info dma[LGUEST_MAX_DMA];
/* Dead? */
const char *dead;
/* The GDT entries copied into lguest_ro_state when running. */
struct desc_struct gdt[GDT_ENTRIES];
/* The IDT entries: some copied into lguest_ro_state when running. */
struct desc_struct idt[IDT_ENTRIES];
/* Virtual clock device */
struct hrtimer hrt;
/* Pending virtual interrupts */
DECLARE_BITMAP(irqs_pending, LGUEST_IRQS);
};
extern struct mutex lguest_lock;
/* core.c: */
u32 lgread_u32(struct lguest *lg, unsigned long addr);
void lgwrite_u32(struct lguest *lg, unsigned long addr, u32 val);
void lgread(struct lguest *lg, void *buf, unsigned long addr, unsigned len);
void lgwrite(struct lguest *lg, unsigned long, const void *buf, unsigned len);
int lguest_address_ok(const struct lguest *lg,
unsigned long addr, unsigned long len);
int run_guest(struct lguest *lg, unsigned long __user *user);
/* interrupts_and_traps.c: */
void maybe_do_interrupt(struct lguest *lg);
int deliver_trap(struct lguest *lg, unsigned int num);
void load_guest_idt_entry(struct lguest *lg, unsigned int i, u32 low, u32 hi);
void guest_set_stack(struct lguest *lg, u32 seg, u32 esp, unsigned int pages);
void pin_stack_pages(struct lguest *lg);
void setup_default_idt_entries(struct lguest_ro_state *state,
const unsigned long *def);
void copy_traps(const struct lguest *lg, struct desc_struct *idt,
const unsigned long *def);
void guest_set_clockevent(struct lguest *lg, unsigned long delta);
void init_clockdev(struct lguest *lg);
/* segments.c: */
void setup_default_gdt_entries(struct lguest_ro_state *state);
void setup_guest_gdt(struct lguest *lg);
void load_guest_gdt(struct lguest *lg, unsigned long table, u32 num);
void guest_load_tls(struct lguest *lg, unsigned long tls_array);
void copy_gdt(const struct lguest *lg, struct desc_struct *gdt);
void copy_gdt_tls(const struct lguest *lg, struct desc_struct *gdt);
/* page_tables.c: */
int init_guest_pagetable(struct lguest *lg, unsigned long pgtable);
void free_guest_pagetable(struct lguest *lg);
void guest_new_pagetable(struct lguest *lg, unsigned long pgtable);
void guest_set_pmd(struct lguest *lg, unsigned long cr3, u32 i);
void guest_pagetable_clear_all(struct lguest *lg);
void guest_pagetable_flush_user(struct lguest *lg);
void guest_set_pte(struct lguest *lg, unsigned long cr3,
unsigned long vaddr, gpte_t val);
void map_switcher_in_guest(struct lguest *lg, struct lguest_pages *pages);
int demand_page(struct lguest *info, unsigned long cr2, int errcode);
void pin_page(struct lguest *lg, unsigned long vaddr);
/* lguest_user.c: */
int lguest_device_init(void);
void lguest_device_remove(void);
/* io.c: */
void lguest_io_init(void);
int bind_dma(struct lguest *lg,
unsigned long key, unsigned long udma, u16 numdmas, u8 interrupt);
void send_dma(struct lguest *info, unsigned long key, unsigned long udma);
void release_all_dma(struct lguest *lg);
unsigned long get_dma_buffer(struct lguest *lg, unsigned long key,
unsigned long *interrupt);
/* hypercalls.c: */
void do_hypercalls(struct lguest *lg);
void write_timestamp(struct lguest *lg);
/*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 does 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(lg, fmt...) \
do { \
if (!(lg)->dead) { \
(lg)->dead = kasprintf(GFP_ATOMIC, fm
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