include/linux/lguest.h

   1 /* Things the lguest guest needs to know.  Note: like all lguest interfaces,
   2  * this is subject to wild and random change between versions. */
   3 #ifndef _LINUX_LGUEST_H
   4 #define _LINUX_LGUEST_H
   5
   6 #ifndef __ASSEMBLY__
   7 #include <linux/time.h>
   8 #include <asm/irq.h>
   9 #include <asm/lguest_hcall.h>
  10
  11 #define LG_CLOCK_MIN_DELTA      100UL
  12 #define LG_CLOCK_MAX_DELTA      ULONG_MAX
  13
  14 /*G:031 The second method of communicating with the Host is to via "struct
  15  * lguest_data".  Once the Guest's initialization hypercall tells the Host where
  16  * this is, the Guest and Host both publish information in it. :*/
  17 struct lguest_data
  18 {
  19         /* 512 == enabled (same as eflags in normal hardware).  The Guest
  20          * changes interrupts so often that a hypercall is too slow. */
  21         unsigned int irq_enabled;
  22         /* Fine-grained interrupt disabling by the Guest */
  23         DECLARE_BITMAP(blocked_interrupts, LGUEST_IRQS);
  24
  25         /* The Host writes the virtual address of the last page fault here,
  26          * which saves the Guest a hypercall.  CR2 is the native register where
  27          * this address would normally be found. */
  28         unsigned long cr2;
  29
  30         /* Wallclock time set by the Host. */
  31         struct timespec time;
  32
  33         /* Interrupt pending set by the Host.  The Guest should do a hypercall
  34          * if it re-enables interrupts and sees this set (to X86_EFLAGS_IF). */
  35         int irq_pending;
  36
  37         /* Async hypercall ring.  Instead of directly making hypercalls, we can
  38          * place them in here for processing the next time the Host wants.
  39          * This batching can be quite efficient. */
  40
  41         /* 0xFF == done (set by Host), 0 == pending (set by Guest). */
  42         u8 hcall_status[LHCALL_RING_SIZE];
  43         /* The actual registers for the hypercalls. */
  44         struct hcall_args hcalls[LHCALL_RING_SIZE];
  45
  46 /* Fields initialized by the Host at boot: */
  47         /* Memory not to try to access */
  48         unsigned long reserve_mem;
  49         /* KHz for the TSC clock. */
  50         u32 tsc_khz;
  51         /* Page where the top-level pagetable is */
  52         unsigned long pgdir;
  53
  54 /* Fields initialized by the Guest at boot: */
  55         /* Instruction range to suppress interrupts even if enabled */
  56         unsigned long noirq_start, noirq_end;
  57         /* Address above which page tables are all identical. */
  58         unsigned long kernel_address;
  59         /* The vector to try to use for system calls (0x40 or 0x80). */
  60         unsigned int syscall_vec;
  61 };
  62 extern struct lguest_data lguest_data;
  63 #endif /* __ASSEMBLY__ */
  64 #endif  /* _LINUX_LGUEST_H */