OvmfPkg/Include/IndustryStandard/Xen/xen.h

   1 /******************************************************************************
   2  * xen.h
   3  *
   4  * Guest OS interface to Xen.
   5  *
   6  * SPDX-License-Identifier: MIT
   7  *
   8  * Copyright (c) 2004, K A Fraser
   9  */
  10
  11 #ifndef __XEN_PUBLIC_XEN_H__
  12 #define __XEN_PUBLIC_XEN_H__
  13
  14 //
  15 // Xen interface version used by Tianocore
  16 //
  17 #define __XEN_INTERFACE_VERSION__  0x00040400
  18
  19 #include "xen-compat.h"
  20
  21 #if defined (MDE_CPU_IA32) || defined (MDE_CPU_X64)
  22   #include "arch-x86/xen.h"
  23 #elif defined (__arm__) || defined (__aarch64__)
  24   #include "arch-arm/xen.h"
  25 #else
  26   #error "Unsupported architecture"
  27 #endif
  28
  29 #ifndef __ASSEMBLY__
  30 /* Guest handles for primitive C types. */
  31 DEFINE_XEN_GUEST_HANDLE (CHAR8);
  32 __DEFINE_XEN_GUEST_HANDLE (uchar, UINT8);
  33 DEFINE_XEN_GUEST_HANDLE (INT32);
  34 __DEFINE_XEN_GUEST_HANDLE (uint, UINT32);
  35   #if __XEN_INTERFACE_VERSION__ < 0x00040300
  36 DEFINE_XEN_GUEST_HANDLE (INTN);
  37 __DEFINE_XEN_GUEST_HANDLE (ulong, UINTN);
  38   #endif
  39 DEFINE_XEN_GUEST_HANDLE (VOID);
  40
  41 DEFINE_XEN_GUEST_HANDLE (UINT64);
  42 DEFINE_XEN_GUEST_HANDLE (xen_pfn_t);
  43 DEFINE_XEN_GUEST_HANDLE (xen_ulong_t);
  44 #endif
  45
  46 /*
  47  * HYPERCALLS
  48  */
  49
  50 /* `incontents 100 hcalls List of hypercalls
  51  * ` enum hypercall_num { // __HYPERVISOR_* => HYPERVISOR_*()
  52  */
  53
  54 #define __HYPERVISOR_set_trap_table                 0
  55 #define __HYPERVISOR_mmu_update                     1
  56 #define __HYPERVISOR_set_gdt                        2
  57 #define __HYPERVISOR_stack_switch                   3
  58 #define __HYPERVISOR_set_callbacks                  4
  59 #define __HYPERVISOR_fpu_taskswitch                 5
  60 #define __HYPERVISOR_sched_op_compat                6/* compat since 0x00030101 */
  61 #define __HYPERVISOR_platform_op                    7
  62 #define __HYPERVISOR_set_debugreg                   8
  63 #define __HYPERVISOR_get_debugreg                   9
  64 #define __HYPERVISOR_update_descriptor              10
  65 #define __HYPERVISOR_memory_op                      12
  66 #define __HYPERVISOR_multicall                      13
  67 #define __HYPERVISOR_update_va_mapping              14
  68 #define __HYPERVISOR_set_timer_op                   15
  69 #define __HYPERVISOR_event_channel_op_compat        16/* compat since 0x00030202 */
  70 #define __HYPERVISOR_xen_version                    17
  71 #define __HYPERVISOR_console_io                     18
  72 #define __HYPERVISOR_physdev_op_compat              19/* compat since 0x00030202 */
  73 #define __HYPERVISOR_grant_table_op                 20
  74 #define __HYPERVISOR_vm_assist                      21
  75 #define __HYPERVISOR_update_va_mapping_otherdomain  22
  76 #define __HYPERVISOR_iret                           23/* x86 only */
  77 #define __HYPERVISOR_vcpu_op                        24
  78 #define __HYPERVISOR_set_segment_base               25/* x86/64 only */
  79 #define __HYPERVISOR_mmuext_op                      26
  80 #define __HYPERVISOR_xsm_op                         27
  81 #define __HYPERVISOR_nmi_op                         28
  82 #define __HYPERVISOR_sched_op                       29
  83 #define __HYPERVISOR_callback_op                    30
  84 #define __HYPERVISOR_xenoprof_op                    31
  85 #define __HYPERVISOR_event_channel_op               32
  86 #define __HYPERVISOR_physdev_op                     33
  87 #define __HYPERVISOR_hvm_op                         34
  88 #define __HYPERVISOR_sysctl                         35
  89 #define __HYPERVISOR_domctl                         36
  90 #define __HYPERVISOR_kexec_op                       37
  91 #define __HYPERVISOR_tmem_op                        38
  92 #define __HYPERVISOR_xc_reserved_op                 39/* reserved for XenClient */
  93
  94 /* Architecture-specific hypercall definitions. */
  95 #define __HYPERVISOR_arch_0  48
  96 #define __HYPERVISOR_arch_1  49
  97 #define __HYPERVISOR_arch_2  50
  98 #define __HYPERVISOR_arch_3  51
  99 #define __HYPERVISOR_arch_4  52
 100 #define __HYPERVISOR_arch_5  53
 101 #define __HYPERVISOR_arch_6  54
 102 #define __HYPERVISOR_arch_7  55
 103
 104 /* ` } */
 105
 106 /*
 107  * HYPERCALL COMPATIBILITY.
 108  */
 109
 110 /* New sched_op hypercall introduced in 0x00030101. */
 111 #if __XEN_INTERFACE_VERSION__ < 0x00030101
 112   #undef __HYPERVISOR_sched_op
 113 #define __HYPERVISOR_sched_op  __HYPERVISOR_sched_op_compat
 114 #endif
 115
 116 /* New event-channel and physdev hypercalls introduced in 0x00030202. */
 117 #if __XEN_INTERFACE_VERSION__ < 0x00030202
 118   #undef __HYPERVISOR_event_channel_op
 119 #define __HYPERVISOR_event_channel_op  __HYPERVISOR_event_channel_op_compat
 120   #undef __HYPERVISOR_physdev_op
 121 #define __HYPERVISOR_physdev_op  __HYPERVISOR_physdev_op_compat
 122 #endif
 123
 124 /* New platform_op hypercall introduced in 0x00030204. */
 125 #if __XEN_INTERFACE_VERSION__ < 0x00030204
 126 #define __HYPERVISOR_dom0_op  __HYPERVISOR_platform_op
 127 #endif
 128
 129 #ifndef __ASSEMBLY__
 130
 131 typedef UINT16 domid_t;
 132
 133 /* Domain ids >= DOMID_FIRST_RESERVED cannot be used for ordinary domains. */
 134 #define DOMID_FIRST_RESERVED  (0x7FF0U)
 135
 136 /* DOMID_SELF is used in certain contexts to refer to oneself. */
 137 #define DOMID_SELF  (0x7FF0U)
 138
 139 /*
 140  * DOMID_IO is used to restrict page-table updates to mapping I/O memory.
 141  * Although no Foreign Domain need be specified to map I/O pages, DOMID_IO
 142  * is useful to ensure that no mappings to the OS's own heap are accidentally
 143  * installed. (e.g., in Linux this could cause havoc as reference counts
 144  * aren't adjusted on the I/O-mapping code path).
 145  * This only makes sense in MMUEXT_SET_FOREIGNDOM, but in that context can
 146  * be specified by any calling domain.
 147  */
 148 #define DOMID_IO  (0x7FF1U)
 149
 150 /*
 151  * DOMID_XEN is used to allow privileged domains to map restricted parts of
 152  * Xen's heap space (e.g., the machine_to_phys table).
 153  * This only makes sense in MMUEXT_SET_FOREIGNDOM, and is only permitted if
 154  * the caller is privileged.
 155  */
 156 #define DOMID_XEN  (0x7FF2U)
 157
 158 /*
 159  * DOMID_COW is used as the owner of sharable pages */
 160 #define DOMID_COW  (0x7FF3U)
 161
 162 /* DOMID_INVALID is used to identify pages with unknown owner. */
 163 #define DOMID_INVALID  (0x7FF4U)
 164
 165 /* Idle domain. */
 166 #define DOMID_IDLE  (0x7FFFU)
 167
 168   #if __XEN_INTERFACE_VERSION__ < 0x00040400
 169
 170 /*
 171  * Event channel endpoints per domain (when using the 2-level ABI):
 172  *  1024 if a INTN is 32 bits; 4096 if a INTN is 64 bits.
 173  */
 174 #define NR_EVENT_CHANNELS  EVTCHN_2L_NR_CHANNELS
 175   #endif
 176
 177 struct vcpu_time_info {
 178   /*
 179    * Updates to the following values are preceded and followed by an
 180    * increment of 'version'. The guest can therefore detect updates by
 181    * looking for changes to 'version'. If the least-significant bit of
 182    * the version number is set then an update is in progress and the guest
 183    * must wait to read a consistent set of values.
 184    * The correct way to interact with the version number is similar to
 185    * Linux's seqlock: see the implementations of read_seqbegin/read_seqretry.
 186    */
 187   UINT32    Version;
 188   UINT32    pad0;
 189   UINT64    TscTimestamp;  /* TSC at last update of time vals.  */
 190   UINT64    SystemTime;    /* Time, in nanosecs, since boot.    */
 191
 192   /*
 193    * Current system time:
 194    *   system_time +
 195    *   ((((tsc - tsc_timestamp) << tsc_shift) * tsc_to_system_mul) >> 32)
 196    * CPU frequency (Hz):
 197    *   ((10^9 << 32) / tsc_to_system_mul) >> tsc_shift
 198    */
 199   UINT32    TscToSystemMultiplier;
 200   INT8      TscShift;
 201   INT8      pad1[3];
 202 }; /* 32 bytes */
 203
 204 typedef struct vcpu_time_info XEN_VCPU_TIME_INFO;
 205
 206 struct vcpu_info {
 207   /*
 208    * 'evtchn_upcall_pending' is written non-zero by Xen to indicate
 209    * a pending notification for a particular VCPU. It is then cleared
 210    * by the guest OS /before/ checking for pending work, thus avoiding
 211    * a set-and-check race. Note that the mask is only accessed by Xen
 212    * on the CPU that is currently hosting the VCPU. This means that the
 213    * pending and mask flags can be updated by the guest without special
 214    * synchronisation (i.e., no need for the x86 LOCK prefix).
 215    * This may seem suboptimal because if the pending flag is set by
 216    * a different CPU then an IPI may be scheduled even when the mask
 217    * is set. However, note:
 218    *  1. The task of 'interrupt holdoff' is covered by the per-event-
 219    *     channel mask bits. A 'noisy' event that is continually being
 220    *     triggered can be masked at source at this very precise
 221    *     granularity.
 222    *  2. The main purpose of the per-VCPU mask is therefore to restrict
 223    *     reentrant execution: whether for concurrency control, or to
 224    *     prevent unbounded stack usage. Whatever the purpose, we expect
 225    *     that the mask will be asserted only for short periods at a time,
 226    *     and so the likelihood of a 'spurious' IPI is suitably small.
 227    * The mask is read before making an event upcall to the guest: a
 228    * non-zero mask therefore guarantees that the VCPU will not receive
 229    * an upcall activation. The mask is cleared when the VCPU requests
 230    * to block: this avoids wakeup-waiting races.
 231    */
 232   UINT8                    evtchn_upcall_pending;
 233  #ifdef XEN_HAVE_PV_UPCALL_MASK
 234   UINT8                    evtchn_upcall_mask;
 235  #else /* XEN_HAVE_PV_UPCALL_MASK */
 236   UINT8                    pad0;
 237  #endif /* XEN_HAVE_PV_UPCALL_MASK */
 238   xen_ulong_t              evtchn_pending_sel;
 239   struct arch_vcpu_info    arch;
 240   struct vcpu_time_info    Time;
 241 }; /* 64 bytes (x86) */
 242
 243   #ifndef __XEN__
 244 typedef struct vcpu_info vcpu_info_t;
 245   #endif
 246
 247 /*
 248  * `incontents 200 startofday_shared Start-of-day shared data structure
 249  * Xen/kernel shared data -- pointer provided in start_info.
 250  *
 251  * This structure is defined to be both smaller than a page, and the
 252  * only data on the shared page, but may vary in actual size even within
 253  * compatible Xen versions; guests should not rely on the size
 254  * of this structure remaining constant.
 255  */
 256 struct shared_info {
 257   struct vcpu_info    VcpuInfo[XEN_LEGACY_MAX_VCPUS];
 258
 259   /*
 260    * A domain can create "event channels" on which it can send and receive
 261    * asynchronous event notifications. There are three classes of event that
 262    * are delivered by this mechanism:
 263    *  1. Bi-directional inter- and intra-domain connections. Domains must
 264    *     arrange out-of-band to set up a connection (usually by allocating
 265    *     an unbound 'listener' port and avertising that via a storage service
 266    *     such as xenstore).
 267    *  2. Physical interrupts. A domain with suitable hardware-access
 268    *     privileges can bind an event-channel port to a physical interrupt
 269    *     source.
 270    *  3. Virtual interrupts ('events'). A domain can bind an event-channel
 271    *     port to a virtual interrupt source, such as the virtual-timer
 272    *     device or the emergency console.
 273    *
 274    * Event channels are addressed by a "port index". Each channel is
 275    * associated with two bits of information:
 276    *  1. PENDING -- notifies the domain that there is a pending notification
 277    *     to be processed. This bit is cleared by the guest.
 278    *  2. MASK -- if this bit is clear then a 0->1 transition of PENDING
 279    *     will cause an asynchronous upcall to be scheduled. This bit is only
 280    *     updated by the guest. It is read-only within Xen. If a channel
 281    *     becomes pending while the channel is masked then the 'edge' is lost
 282    *     (i.e., when the channel is unmasked, the guest must manually handle
 283    *     pending notifications as no upcall will be scheduled by Xen).
 284    *
 285    * To expedite scanning of pending notifications, any 0->1 pending
 286    * transition on an unmasked channel causes a corresponding bit in a
 287    * per-vcpu selector word to be set. Each bit in the selector covers a
 288    * 'C INTN' in the PENDING bitfield array.
 289    */
 290   xen_ulong_t                evtchn_pending[sizeof (xen_ulong_t) * 8];
 291   xen_ulong_t                evtchn_mask[sizeof (xen_ulong_t) * 8];
 292
 293   /*
 294    * Wallclock time: updated only by control software. Guests should base
 295    * their gettimeofday() syscall on this wallclock-base value.
 296    */
 297   UINT32                     wc_version; /* Version counter: see vcpu_time_info_t. */
 298   UINT32                     wc_sec;     /* Secs  00:00:00 UTC, Jan 1, 1970.  */
 299   UINT32                     wc_nsec;    /* Nsecs 00:00:00 UTC, Jan 1, 1970.  */
 300
 301   struct arch_shared_info    arch;
 302 };
 303
 304   #ifndef __XEN__
 305 typedef struct shared_info shared_info_t;
 306 typedef struct shared_info XEN_SHARED_INFO;
 307   #endif
 308
 309 /* Turn a plain number into a C UINTN constant. */
 310 #define __mk_unsigned_long(x)  x ## UL
 311 #define mk_unsigned_long(x)    __mk_unsigned_long(x)
 312
 313 __DEFINE_XEN_GUEST_HANDLE (uint8, UINT8);
 314 __DEFINE_XEN_GUEST_HANDLE (uint16, UINT16);
 315 __DEFINE_XEN_GUEST_HANDLE (uint32, UINT32);
 316 __DEFINE_XEN_GUEST_HANDLE (uint64, UINT64);
 317
 318 #else /* __ASSEMBLY__ */
 319
 320 /* In assembly code we cannot use C numeric constant suffixes. */
 321 #define mk_unsigned_long(x)  x
 322
 323 #endif /* !__ASSEMBLY__ */
 324
 325 #endif /* __XEN_PUBLIC_XEN_H__ */
 326
 327 /*
 328  * Local variables:
 329  * mode: C
 330  * c-file-style: "BSD"
 331  * c-basic-offset: 4
 332  * tab-width: 4
 333  * indent-tabs-mode: nil
 334  * End:
 335  */