LXR linux/include/linux/lguest.h

   1/*
   2 * Things the lguest guest needs to know.  Note: like all lguest interfaces,
   3 * this is subject to wild and random change between versions.
   4 */
   5#ifndef _LINUX_LGUEST_H
   6#define _LINUX_LGUEST_H
   7
   8#ifndef __ASSEMBLY__
   9#include <linux/time.h>
  10#include <asm/irq.h>
  11#include <asm/lguest_hcall.h>
  12
  13#define LG_CLOCK_MIN_DELTA      100UL
  14#define LG_CLOCK_MAX_DELTA      ULONG_MAX
  15
  16/*G:031
  17 * The second method of communicating with the Host is to via "struct
  18 * lguest_data".  Once the Guest's initialization hypercall tells the Host where
  19 * this is, the Guest and Host both publish information in it.
  20:*/
  21struct lguest_data {
  22        /*
  23         * 512 == enabled (same as eflags in normal hardware).  The Guest
  24         * changes interrupts so often that a hypercall is too slow.
  25         */
  26        unsigned int irq_enabled;
  27        /* Fine-grained interrupt disabling by the Guest */
  28        DECLARE_BITMAP(blocked_interrupts, LGUEST_IRQS);
  29
  30        /*
  31         * The Host writes the virtual address of the last page fault here,
  32         * which saves the Guest a hypercall.  CR2 is the native register where
  33         * this address would normally be found.
  34         */
  35        unsigned long cr2;
  36
  37        /* Wallclock time set by the Host. */
  38        struct timespec time;
  39
  40        /*
  41         * Interrupt pending set by the Host.  The Guest should do a hypercall
  42         * if it re-enables interrupts and sees this set (to X86_EFLAGS_IF).
  43         */
  44        int irq_pending;
  45
  46        /*
  47         * Async hypercall ring.  Instead of directly making hypercalls, we can
  48         * place them in here for processing the next time the Host wants.
  49         * This batching can be quite efficient.
  50         */
  51
  52        /* 0xFF == done (set by Host), 0 == pending (set by Guest). */
  53        u8 hcall_status[LHCALL_RING_SIZE];
  54        /* The actual registers for the hypercalls. */
  55        struct hcall_args hcalls[LHCALL_RING_SIZE];
  56
  57/* Fields initialized by the Host at boot: */
  58        /* Memory not to try to access */
  59        unsigned long reserve_mem;
  60        /* KHz for the TSC clock. */
  61        u32 tsc_khz;
  62
  63/* Fields initialized by the Guest at boot: */
  64        /* Instruction to suppress interrupts even if enabled */
  65        unsigned long noirq_iret;
  66        /* Address above which page tables are all identical. */
  67        unsigned long kernel_address;
  68        /* The vector to try to use for system calls (0x40 or 0x80). */
  69        unsigned int syscall_vec;
  70};
  71extern struct lguest_data lguest_data;
  72#endif /* __ASSEMBLY__ */
  73#endif  /* _LINUX_LGUEST_H */
  74