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:032 The second method of communicating with the Host is to via "struct
  15  * lguest_data".  The Guest's very first hypercall is to tell the Host where
  16  * this is, and then 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         /* Async hypercall ring.  Instead of directly making hypercalls, we can
  34          * place them in here for processing the next time the Host wants.
  35          * This batching can be quite efficient. */
  36
  37         /* 0xFF == done (set by Host), 0 == pending (set by Guest). */
  38         u8 hcall_status[LHCALL_RING_SIZE];
  39         /* The actual registers for the hypercalls. */
  40         struct hcall_args hcalls[LHCALL_RING_SIZE];
  41
  42 /* Fields initialized by the Host at boot: */
  43         /* Memory not to try to access */
  44         unsigned long reserve_mem;
  45         /* KHz for the TSC clock. */
  46         u32 tsc_khz;
  47         /* Page where the top-level pagetable is */
  48         unsigned long pgdir;
  49
  50 /* Fields initialized by the Guest at boot: */
  51         /* Instruction range to suppress interrupts even if enabled */
  52         unsigned long noirq_start, noirq_end;
  53         /* Address above which page tables are all identical. */
  54         unsigned long kernel_address;
  55         /* The vector to try to use for system calls (0x40 or 0x80). */
  56         unsigned int syscall_vec;
  57 };
  58 extern struct lguest_data lguest_data;
  59 #endif /* __ASSEMBLY__ */
  60 #endif  /* _LINUX_LGUEST_H */