include/hw/xen/interface/vcpu.h

   1 /* SPDX-License-Identifier: MIT */
   2 /******************************************************************************
   3  * vcpu.h
   4  *
   5  * VCPU initialisation, query, and hotplug.
   6  *
   7  * Copyright (c) 2005, Keir Fraser <keir@xensource.com>
   8  */
   9
  10 #ifndef __XEN_PUBLIC_VCPU_H__
  11 #define __XEN_PUBLIC_VCPU_H__
  12
  13 #include "xen.h"
  14
  15 /*
  16  * Prototype for this hypercall is:
  17  *  long vcpu_op(int cmd, unsigned int vcpuid, void *extra_args)
  18  * @cmd        == VCPUOP_??? (VCPU operation).
  19  * @vcpuid     == VCPU to operate on.
  20  * @extra_args == Operation-specific extra arguments (NULL if none).
  21  */
  22
  23 /*
  24  * Initialise a VCPU. Each VCPU can be initialised only once. A
  25  * newly-initialised VCPU will not run until it is brought up by VCPUOP_up.
  26  *
  27  * @extra_arg == For PV or ARM guests this is a pointer to a vcpu_guest_context
  28  *               structure containing the initial state for the VCPU. For x86
  29  *               HVM based guests this is a pointer to a vcpu_hvm_context
  30  *               structure.
  31  */
  32 #define VCPUOP_initialise            0
  33
  34 /*
  35  * Bring up a VCPU. This makes the VCPU runnable. This operation will fail
  36  * if the VCPU has not been initialised (VCPUOP_initialise).
  37  */
  38 #define VCPUOP_up                    1
  39
  40 /*
  41  * Bring down a VCPU (i.e., make it non-runnable).
  42  * There are a few caveats that callers should observe:
  43  *  1. This operation may return, and VCPU_is_up may return false, before the
  44  *     VCPU stops running (i.e., the command is asynchronous). It is a good
  45  *     idea to ensure that the VCPU has entered a non-critical loop before
  46  *     bringing it down. Alternatively, this operation is guaranteed
  47  *     synchronous if invoked by the VCPU itself.
  48  *  2. After a VCPU is initialised, there is currently no way to drop all its
  49  *     references to domain memory. Even a VCPU that is down still holds
  50  *     memory references via its pagetable base pointer and GDT. It is good
  51  *     practise to move a VCPU onto an 'idle' or default page table, LDT and
  52  *     GDT before bringing it down.
  53  */
  54 #define VCPUOP_down                  2
  55
  56 /* Returns 1 if the given VCPU is up. */
  57 #define VCPUOP_is_up                 3
  58
  59 /*
  60  * Return information about the state and running time of a VCPU.
  61  * @extra_arg == pointer to vcpu_runstate_info structure.
  62  */
  63 #define VCPUOP_get_runstate_info     4
  64 struct vcpu_runstate_info {
  65     /* VCPU's current state (RUNSTATE_*). */
  66     int      state;
  67     /* When was current state entered (system time, ns)? */
  68     uint64_t state_entry_time;
  69     /*
  70      * Update indicator set in state_entry_time:
  71      * When activated via VMASST_TYPE_runstate_update_flag, set during
  72      * updates in guest memory mapped copy of vcpu_runstate_info.
  73      */
  74 #define XEN_RUNSTATE_UPDATE          (xen_mk_ullong(1) << 63)
  75     /*
  76      * Time spent in each RUNSTATE_* (ns). The sum of these times is
  77      * guaranteed not to drift from system time.
  78      */
  79     uint64_t time[4];
  80 };
  81 typedef struct vcpu_runstate_info vcpu_runstate_info_t;
  82 DEFINE_XEN_GUEST_HANDLE(vcpu_runstate_info_t);
  83
  84 /* VCPU is currently running on a physical CPU. */
  85 #define RUNSTATE_running  0
  86
  87 /* VCPU is runnable, but not currently scheduled on any physical CPU. */
  88 #define RUNSTATE_runnable 1
  89
  90 /* VCPU is blocked (a.k.a. idle). It is therefore not runnable. */
  91 #define RUNSTATE_blocked  2
  92
  93 /*
  94  * VCPU is not runnable, but it is not blocked.
  95  * This is a 'catch all' state for things like hotplug and pauses by the
  96  * system administrator (or for critical sections in the hypervisor).
  97  * RUNSTATE_blocked dominates this state (it is the preferred state).
  98  */
  99 #define RUNSTATE_offline  3
 100
 101 /*
 102  * Register a shared memory area from which the guest may obtain its own
 103  * runstate information without needing to execute a hypercall.
 104  * Notes:
 105  *  1. The registered address may be virtual or physical or guest handle,
 106  *     depending on the platform. Virtual address or guest handle should be
 107  *     registered on x86 systems.
 108  *  2. Only one shared area may be registered per VCPU. The shared area is
 109  *     updated by the hypervisor each time the VCPU is scheduled. Thus
 110  *     runstate.state will always be RUNSTATE_running and
 111  *     runstate.state_entry_time will indicate the system time at which the
 112  *     VCPU was last scheduled to run.
 113  * @extra_arg == pointer to vcpu_register_runstate_memory_area structure.
 114  */
 115 #define VCPUOP_register_runstate_memory_area 5
 116 struct vcpu_register_runstate_memory_area {
 117     union {
 118         XEN_GUEST_HANDLE(vcpu_runstate_info_t) h;
 119         struct vcpu_runstate_info *v;
 120         uint64_t p;
 121     } addr;
 122 };
 123 typedef struct vcpu_register_runstate_memory_area vcpu_register_runstate_memory_area_t;
 124 DEFINE_XEN_GUEST_HANDLE(vcpu_register_runstate_memory_area_t);
 125
 126 /*
 127  * Set or stop a VCPU's periodic timer. Every VCPU has one periodic timer
 128  * which can be set via these commands. Periods smaller than one millisecond
 129  * may not be supported.
 130  */
 131 #define VCPUOP_set_periodic_timer    6 /* arg == vcpu_set_periodic_timer_t */
 132 #define VCPUOP_stop_periodic_timer   7 /* arg == NULL */
 133 struct vcpu_set_periodic_timer {
 134     uint64_t period_ns;
 135 };
 136 typedef struct vcpu_set_periodic_timer vcpu_set_periodic_timer_t;
 137 DEFINE_XEN_GUEST_HANDLE(vcpu_set_periodic_timer_t);
 138
 139 /*
 140  * Set or stop a VCPU's single-shot timer. Every VCPU has one single-shot
 141  * timer which can be set via these commands.
 142  */
 143 #define VCPUOP_set_singleshot_timer  8 /* arg == vcpu_set_singleshot_timer_t */
 144 #define VCPUOP_stop_singleshot_timer 9 /* arg == NULL */
 145 struct vcpu_set_singleshot_timer {
 146     uint64_t timeout_abs_ns;   /* Absolute system time value in nanoseconds. */
 147     uint32_t flags;            /* VCPU_SSHOTTMR_??? */
 148 };
 149 typedef struct vcpu_set_singleshot_timer vcpu_set_singleshot_timer_t;
 150 DEFINE_XEN_GUEST_HANDLE(vcpu_set_singleshot_timer_t);
 151
 152 /* Flags to VCPUOP_set_singleshot_timer. */
 153  /* Require the timeout to be in the future (return -ETIME if it's passed). */
 154 #define _VCPU_SSHOTTMR_future (0)
 155 #define VCPU_SSHOTTMR_future  (1U << _VCPU_SSHOTTMR_future)
 156
 157 /*
 158  * Register a memory location in the guest address space for the
 159  * vcpu_info structure.  This allows the guest to place the vcpu_info
 160  * structure in a convenient place, such as in a per-cpu data area.
 161  * The pointer need not be page aligned, but the structure must not
 162  * cross a page boundary.
 163  *
 164  * This may be called only once per vcpu.
 165  */
 166 #define VCPUOP_register_vcpu_info   10  /* arg == vcpu_register_vcpu_info_t */
 167 struct vcpu_register_vcpu_info {
 168     uint64_t mfn;    /* mfn of page to place vcpu_info */
 169     uint32_t offset; /* offset within page */
 170     uint32_t rsvd;   /* unused */
 171 };
 172 typedef struct vcpu_register_vcpu_info vcpu_register_vcpu_info_t;
 173 DEFINE_XEN_GUEST_HANDLE(vcpu_register_vcpu_info_t);
 174
 175 /* Send an NMI to the specified VCPU. @extra_arg == NULL. */
 176 #define VCPUOP_send_nmi             11
 177
 178 /*
 179  * Get the physical ID information for a pinned vcpu's underlying physical
 180  * processor.  The physical ID informmation is architecture-specific.
 181  * On x86: id[31:0]=apic_id, id[63:32]=acpi_id.
 182  * This command returns -EINVAL if it is not a valid operation for this VCPU.
 183  */
 184 #define VCPUOP_get_physid           12 /* arg == vcpu_get_physid_t */
 185 struct vcpu_get_physid {
 186     uint64_t phys_id;
 187 };
 188 typedef struct vcpu_get_physid vcpu_get_physid_t;
 189 DEFINE_XEN_GUEST_HANDLE(vcpu_get_physid_t);
 190 #define xen_vcpu_physid_to_x86_apicid(physid) ((uint32_t)(physid))
 191 #define xen_vcpu_physid_to_x86_acpiid(physid) ((uint32_t)((physid) >> 32))
 192
 193 /*
 194  * Register a memory location to get a secondary copy of the vcpu time
 195  * parameters.  The master copy still exists as part of the vcpu shared
 196  * memory area, and this secondary copy is updated whenever the master copy
 197  * is updated (and using the same versioning scheme for synchronisation).
 198  *
 199  * The intent is that this copy may be mapped (RO) into userspace so
 200  * that usermode can compute system time using the time info and the
 201  * tsc.  Usermode will see an array of vcpu_time_info structures, one
 202  * for each vcpu, and choose the right one by an existing mechanism
 203  * which allows it to get the current vcpu number (such as via a
 204  * segment limit).  It can then apply the normal algorithm to compute
 205  * system time from the tsc.
 206  *
 207  * @extra_arg == pointer to vcpu_register_time_info_memory_area structure.
 208  */
 209 #define VCPUOP_register_vcpu_time_memory_area   13
 210 DEFINE_XEN_GUEST_HANDLE(vcpu_time_info_t);
 211 struct vcpu_register_time_memory_area {
 212     union {
 213         XEN_GUEST_HANDLE(vcpu_time_info_t) h;
 214         struct vcpu_time_info *v;
 215         uint64_t p;
 216     } addr;
 217 };
 218 typedef struct vcpu_register_time_memory_area vcpu_register_time_memory_area_t;
 219 DEFINE_XEN_GUEST_HANDLE(vcpu_register_time_memory_area_t);
 220
 221 #endif /* __XEN_PUBLIC_VCPU_H__ */
 222
 223 /*
 224  * Local variables:
 225  * mode: C
 226  * c-file-style: "BSD"
 227  * c-basic-offset: 4
 228  * tab-width: 4
 229  * indent-tabs-mode: nil
 230  * End:
 231  */