1/* SPDX-License-Identifier: MIT */
2/******************************************************************************
3 * xen.h
4 *
5 * Guest OS interface to Xen.
6 *
7 * Copyright (c) 2004, K A Fraser
8 */
9
10#ifndef __XEN_PUBLIC_XEN_H__
11#define __XEN_PUBLIC_XEN_H__
12
13#include <asm/xen/interface.h>
14
15/*
16 * XEN "SYSTEM CALLS" (a.k.a. HYPERCALLS).
17 */
18
19/*
20 * x86_32: EAX = vector; EBX, ECX, EDX, ESI, EDI = args 1, 2, 3, 4, 5.
21 *         EAX = return value
22 *         (argument registers may be clobbered on return)
23 * x86_64: RAX = vector; RDI, RSI, RDX, R10, R8, R9 = args 1, 2, 3, 4, 5, 6.
24 *         RAX = return value
25 *         (argument registers not clobbered on return; RCX, R11 are)
26 */
27#define __HYPERVISOR_set_trap_table        0
28#define __HYPERVISOR_mmu_update            1
29#define __HYPERVISOR_set_gdt               2
30#define __HYPERVISOR_stack_switch          3
31#define __HYPERVISOR_set_callbacks         4
32#define __HYPERVISOR_fpu_taskswitch        5
33#define __HYPERVISOR_sched_op_compat       6
34#define __HYPERVISOR_platform_op           7
35#define __HYPERVISOR_set_debugreg          8
36#define __HYPERVISOR_get_debugreg          9
37#define __HYPERVISOR_update_descriptor    10
38#define __HYPERVISOR_memory_op            12
39#define __HYPERVISOR_multicall            13
40#define __HYPERVISOR_update_va_mapping    14
41#define __HYPERVISOR_set_timer_op         15
42#define __HYPERVISOR_event_channel_op_compat 16
43#define __HYPERVISOR_xen_version          17
44#define __HYPERVISOR_console_io           18
45#define __HYPERVISOR_physdev_op_compat    19
46#define __HYPERVISOR_grant_table_op       20
47#define __HYPERVISOR_vm_assist            21
48#define __HYPERVISOR_update_va_mapping_otherdomain 22
49#define __HYPERVISOR_iret                 23 /* x86 only */
50#define __HYPERVISOR_vcpu_op              24
51#define __HYPERVISOR_set_segment_base     25 /* x86/64 only */
52#define __HYPERVISOR_mmuext_op            26
53#define __HYPERVISOR_xsm_op               27
54#define __HYPERVISOR_nmi_op               28
55#define __HYPERVISOR_sched_op             29
56#define __HYPERVISOR_callback_op          30
57#define __HYPERVISOR_xenoprof_op          31
58#define __HYPERVISOR_event_channel_op     32
59#define __HYPERVISOR_physdev_op           33
60#define __HYPERVISOR_hvm_op               34
61#define __HYPERVISOR_sysctl               35
62#define __HYPERVISOR_domctl               36
63#define __HYPERVISOR_kexec_op             37
64#define __HYPERVISOR_tmem_op              38
65#define __HYPERVISOR_xc_reserved_op       39 /* reserved for XenClient */
66#define __HYPERVISOR_xenpmu_op            40
67#define __HYPERVISOR_dm_op                41
68
69/* Architecture-specific hypercall definitions. */
70#define __HYPERVISOR_arch_0               48
71#define __HYPERVISOR_arch_1               49
72#define __HYPERVISOR_arch_2               50
73#define __HYPERVISOR_arch_3               51
74#define __HYPERVISOR_arch_4               52
75#define __HYPERVISOR_arch_5               53
76#define __HYPERVISOR_arch_6               54
77#define __HYPERVISOR_arch_7               55
78
79/*
80 * VIRTUAL INTERRUPTS
81 *
82 * Virtual interrupts that a guest OS may receive from Xen.
83 * In the side comments, 'V.' denotes a per-VCPU VIRQ while 'G.' denotes a
84 * global VIRQ. The former can be bound once per VCPU and cannot be re-bound.
85 * The latter can be allocated only once per guest: they must initially be
86 * allocated to VCPU0 but can subsequently be re-bound.
87 */
88#define VIRQ_TIMER      0  /* V. Timebase update, and/or requested timeout.  */
89#define VIRQ_DEBUG      1  /* V. Request guest to dump debug info.           */
90#define VIRQ_CONSOLE    2  /* G. (DOM0) Bytes received on emergency console. */
91#define VIRQ_DOM_EXC    3  /* G. (DOM0) Exceptional event for some domain.   */
92#define VIRQ_TBUF       4  /* G. (DOM0) Trace buffer has records available.  */
93#define VIRQ_DEBUGGER   6  /* G. (DOM0) A domain has paused for debugging.   */
94#define VIRQ_XENOPROF   7  /* V. XenOprofile interrupt: new sample available */
95#define VIRQ_CON_RING   8  /* G. (DOM0) Bytes received on console            */
96#define VIRQ_PCPU_STATE 9  /* G. (DOM0) PCPU state changed                   */
97#define VIRQ_MEM_EVENT  10 /* G. (DOM0) A memory event has occured           */
98#define VIRQ_XC_RESERVED 11 /* G. Reserved for XenClient                     */
99#define VIRQ_ENOMEM     12 /* G. (DOM0) Low on heap memory       */
100#define VIRQ_XENPMU     13  /* PMC interrupt                                 */
101
102/* Architecture-specific VIRQ definitions. */
103#define VIRQ_ARCH_0    16
104#define VIRQ_ARCH_1    17
105#define VIRQ_ARCH_2    18
106#define VIRQ_ARCH_3    19
107#define VIRQ_ARCH_4    20
108#define VIRQ_ARCH_5    21
109#define VIRQ_ARCH_6    22
110#define VIRQ_ARCH_7    23
111
112#define NR_VIRQS       24
113
114/*
115 * enum neg_errnoval HYPERVISOR_mmu_update(const struct mmu_update reqs[],
116 *                                         unsigned count, unsigned *done_out,
117 *                                         unsigned foreigndom)
118 * @reqs is an array of mmu_update_t structures ((ptr, val) pairs).
119 * @count is the length of the above array.
120 * @pdone is an output parameter indicating number of completed operations
121 * @foreigndom[15:0]: FD, the expected owner of data pages referenced in this
122 *                    hypercall invocation. Can be DOMID_SELF.
123 * @foreigndom[31:16]: PFD, the expected owner of pagetable pages referenced
124 *                     in this hypercall invocation. The value of this field
125 *                     (x) encodes the PFD as follows:
126 *                     x == 0 => PFD == DOMID_SELF
127 *                     x != 0 => PFD == x - 1
128 *
129 * Sub-commands: ptr[1:0] specifies the appropriate MMU_* command.
130 * -------------
131 * ptr[1:0] == MMU_NORMAL_PT_UPDATE:
132 * Updates an entry in a page table belonging to PFD. If updating an L1 table,
133 * and the new table entry is valid/present, the mapped frame must belong to
134 * FD. If attempting to map an I/O page then the caller assumes the privilege
135 * of the FD.
136 * FD == DOMID_IO: Permit /only/ I/O mappings, at the priv level of the caller.
137 * FD == DOMID_XEN: Map restricted areas of Xen's heap space.
138 * ptr[:2]  -- Machine address of the page-table entry to modify.
139 * val      -- Value to write.
140 *
141 * There also certain implicit requirements when using this hypercall. The
142 * pages that make up a pagetable must be mapped read-only in the guest.
143 * This prevents uncontrolled guest updates to the pagetable. Xen strictly
144 * enforces this, and will disallow any pagetable update which will end up
145 * mapping pagetable page RW, and will disallow using any writable page as a
146 * pagetable. In practice it means that when constructing a page table for a
147 * process, thread, etc, we MUST be very dilligient in following these rules:
148 *  1). Start with top-level page (PGD or in Xen language: L4). Fill out
149 *      the entries.
150 *  2). Keep on going, filling out the upper (PUD or L3), and middle (PMD
151 *      or L2).
152 *  3). Start filling out the PTE table (L1) with the PTE entries. Once
153 *      done, make sure to set each of those entries to RO (so writeable bit
154 *      is unset). Once that has been completed, set the PMD (L2) for this
155 *      PTE table as RO.
156 *  4). When completed with all of the PMD (L2) entries, and all of them have
157 *      been set to RO, make sure to set RO the PUD (L3). Do the same
158 *      operation on PGD (L4) pagetable entries that have a PUD (L3) entry.
159 *  5). Now before you can use those pages (so setting the cr3), you MUST also
160 *      pin them so that the hypervisor can verify the entries. This is done
161 *      via the HYPERVISOR_mmuext_op(MMUEXT_PIN_L4_TABLE, guest physical frame
162 *      number of the PGD (L4)). And this point the HYPERVISOR_mmuext_op(
163 *      MMUEXT_NEW_BASEPTR, guest physical frame number of the PGD (L4)) can be
164 *      issued.
165 * For 32-bit guests, the L4 is not used (as there is less pagetables), so
166 * instead use L3.
167 * At this point the pagetables can be modified using the MMU_NORMAL_PT_UPDATE
168 * hypercall. Also if so desired the OS can also try to write to the PTE
169 * and be trapped by the hypervisor (as the PTE entry is RO).
170 *
171 * To deallocate the pages, the operations are the reverse of the steps
172 * mentioned above. The argument is MMUEXT_UNPIN_TABLE for all levels and the
173 * pagetable MUST not be in use (meaning that the cr3 is not set to it).
174 *
175 * ptr[1:0] == MMU_MACHPHYS_UPDATE:
176 * Updates an entry in the machine->pseudo-physical mapping table.
177 * ptr[:2]  -- Machine address within the frame whose mapping to modify.
178 *             The frame must belong to the FD, if one is specified.
179 * val      -- Value to write into the mapping entry.
180 *
181 * ptr[1:0] == MMU_PT_UPDATE_PRESERVE_AD:
182 * As MMU_NORMAL_PT_UPDATE above, but A/D bits currently in the PTE are ORed
183 * with those in @val.
184 *
185 * @val is usually the machine frame number along with some attributes.
186 * The attributes by default follow the architecture defined bits. Meaning that
187 * if this is a X86_64 machine and four page table layout is used, the layout
188 * of val is:
189 *  - 63 if set means No execute (NX)
190 *  - 46-13 the machine frame number
191 *  - 12 available for guest
192 *  - 11 available for guest
193 *  - 10 available for guest
194 *  - 9 available for guest
195 *  - 8 global
196 *  - 7 PAT (PSE is disabled, must use hypercall to make 4MB or 2MB pages)
197 *  - 6 dirty
198 *  - 5 accessed
199 *  - 4 page cached disabled
200 *  - 3 page write through
201 *  - 2 userspace accessible
202 *  - 1 writeable
203 *  - 0 present
204 *
205 *  The one bits that does not fit with the default layout is the PAGE_PSE
206 *  also called PAGE_PAT). The MMUEXT_[UN]MARK_SUPER arguments to the
207 *  HYPERVISOR_mmuext_op serve as mechanism to set a pagetable to be 4MB
208 *  (or 2MB) instead of using the PAGE_PSE bit.
209 *
210 *  The reason that the PAGE_PSE (bit 7) is not being utilized is due to Xen
211 *  using it as the Page Attribute Table (PAT) bit - for details on it please
212 *  refer to Intel SDM 10.12. The PAT allows to set the caching attributes of
213 *  pages instead of using MTRRs.
214 *
215 *  The PAT MSR is as follows (it is a 64-bit value, each entry is 8 bits):
216 *                    PAT4                 PAT0
217 *  +-----+-----+----+----+----+-----+----+----+
218 *  | UC  | UC- | WC | WB | UC | UC- | WC | WB |  <= Linux
219 *  +-----+-----+----+----+----+-----+----+----+
220 *  | UC  | UC- | WT | WB | UC | UC- | WT | WB |  <= BIOS (default when machine boots)
221 *  +-----+-----+----+----+----+-----+----+----+
222 *  | rsv | rsv | WP | WC | UC | UC- | WT | WB |  <= Xen
223 *  +-----+-----+----+----+----+-----+----+----+
224 *
225 *  The lookup of this index table translates to looking up
226 *  Bit 7, Bit 4, and Bit 3 of val entry:
227 *
228 *  PAT/PSE (bit 7) ... PCD (bit 4) .. PWT (bit 3).
229 *
230 *  If all bits are off, then we are using PAT0. If bit 3 turned on,
231 *  then we are using PAT1, if bit 3 and bit 4, then PAT2..
232 *
233 *  As you can see, the Linux PAT1 translates to PAT4 under Xen. Which means
234 *  that if a guest that follows Linux's PAT setup and would like to set Write
235 *  Combined on pages it MUST use PAT4 entry. Meaning that Bit 7 (PAGE_PAT) is
236 *  set. For example, under Linux it only uses PAT0, PAT1, and PAT2 for the
237 *  caching as:
238 *
239 *   WB = none (so PAT0)
240 *   WC = PWT (bit 3 on)
241 *   UC = PWT | PCD (bit 3 and 4 are on).
242 *
243 * To make it work with Xen, it needs to translate the WC bit as so:
244 *
245 *  PWT (so bit 3 on) --> PAT (so bit 7 is on) and clear bit 3
246 *
247 * And to translate back it would:
248 *
249 * PAT (bit 7 on) --> PWT (bit 3 on) and clear bit 7.
250 */
251#define MMU_NORMAL_PT_UPDATE       0 /* checked '*ptr = val'. ptr is MA.      */
252#define MMU_MACHPHYS_UPDATE        1 /* ptr = MA of frame to modify entry for */
253#define MMU_PT_UPDATE_PRESERVE_AD  2 /* atomically: *ptr = val | (*ptr&(A|D)) */
254#define MMU_PT_UPDATE_NO_TRANSLATE 3 /* checked '*ptr = val'. ptr is MA.      */
255
256/*
257 * MMU EXTENDED OPERATIONS
258 *
259 * enum neg_errnoval HYPERVISOR_mmuext_op(mmuext_op_t uops[],
260 *                                        unsigned int count,
261 *                                        unsigned int *pdone,
262 *                                        unsigned int foreigndom)
263 */
264/* HYPERVISOR_mmuext_op() accepts a list of mmuext_op structures.
265 * A foreigndom (FD) can be specified (or DOMID_SELF for none).
266 * Where the FD has some effect, it is described below.
267 *
268 * cmd: MMUEXT_(UN)PIN_*_TABLE
269 * mfn: Machine frame number to be (un)pinned as a p.t. page.
270 *      The frame must belong to the FD, if one is specified.
271 *
272 * cmd: MMUEXT_NEW_BASEPTR
273 * mfn: Machine frame number of new page-table base to install in MMU.
274 *
275 * cmd: MMUEXT_NEW_USER_BASEPTR [x86/64 only]
276 * mfn: Machine frame number of new page-table base to install in MMU
277 *      when in user space.
278 *
279 * cmd: MMUEXT_TLB_FLUSH_LOCAL
280 * No additional arguments. Flushes local TLB.
281 *
282 * cmd: MMUEXT_INVLPG_LOCAL
283 * linear_addr: Linear address to be flushed from the local TLB.
284 *
285 * cmd: MMUEXT_TLB_FLUSH_MULTI
286 * vcpumask: Pointer to bitmap of VCPUs to be flushed.
287 *
288 * cmd: MMUEXT_INVLPG_MULTI
289 * linear_addr: Linear address to be flushed.
290 * vcpumask: Pointer to bitmap of VCPUs to be flushed.
291 *
292 * cmd: MMUEXT_TLB_FLUSH_ALL
293 * No additional arguments. Flushes all VCPUs' TLBs.
294 *
295 * cmd: MMUEXT_INVLPG_ALL
296 * linear_addr: Linear address to be flushed from all VCPUs' TLBs.
297 *
298 * cmd: MMUEXT_FLUSH_CACHE
299 * No additional arguments. Writes back and flushes cache contents.
300 *
301 * cmd: MMUEXT_FLUSH_CACHE_GLOBAL
302 * No additional arguments. Writes back and flushes cache contents
303 * on all CPUs in the system.
304 *
305 * cmd: MMUEXT_SET_LDT
306 * linear_addr: Linear address of LDT base (NB. must be page-aligned).
307 * nr_ents: Number of entries in LDT.
308 *
309 * cmd: MMUEXT_CLEAR_PAGE
310 * mfn: Machine frame number to be cleared.
311 *
312 * cmd: MMUEXT_COPY_PAGE
313 * mfn: Machine frame number of the destination page.
314 * src_mfn: Machine frame number of the source page.
315 *
316 * cmd: MMUEXT_[UN]MARK_SUPER
317 * mfn: Machine frame number of head of superpage to be [un]marked.
318 */
319#define MMUEXT_PIN_L1_TABLE      0
320#define MMUEXT_PIN_L2_TABLE      1
321#define MMUEXT_PIN_L3_TABLE      2
322#define MMUEXT_PIN_L4_TABLE      3
323#define MMUEXT_UNPIN_TABLE       4
324#define MMUEXT_NEW_BASEPTR       5
325#define MMUEXT_TLB_FLUSH_LOCAL   6
326#define MMUEXT_INVLPG_LOCAL      7
327#define MMUEXT_TLB_FLUSH_MULTI   8
328#define MMUEXT_INVLPG_MULTI      9
329#define MMUEXT_TLB_FLUSH_ALL    10
330#define MMUEXT_INVLPG_ALL       11
331#define MMUEXT_FLUSH_CACHE      12
332#define MMUEXT_SET_LDT          13
333#define MMUEXT_NEW_USER_BASEPTR 15
334#define MMUEXT_CLEAR_PAGE       16
335#define MMUEXT_COPY_PAGE        17
336#define MMUEXT_FLUSH_CACHE_GLOBAL 18
337#define MMUEXT_MARK_SUPER       19
338#define MMUEXT_UNMARK_SUPER     20
339
340#ifndef __ASSEMBLY__
341struct mmuext_op {
342	unsigned int cmd;
343	union {
344		/* [UN]PIN_TABLE, NEW_BASEPTR, NEW_USER_BASEPTR
345		 * CLEAR_PAGE, COPY_PAGE, [UN]MARK_SUPER */
346		xen_pfn_t mfn;
347		/* INVLPG_LOCAL, INVLPG_ALL, SET_LDT */
348		unsigned long linear_addr;
349	} arg1;
350	union {
351		/* SET_LDT */
352		unsigned int nr_ents;
353		/* TLB_FLUSH_MULTI, INVLPG_MULTI */
354		void *vcpumask;
355		/* COPY_PAGE */
356		xen_pfn_t src_mfn;
357	} arg2;
358};
359DEFINE_GUEST_HANDLE_STRUCT(mmuext_op);
360#endif
361
362/* These are passed as 'flags' to update_va_mapping. They can be ORed. */
363/* When specifying UVMF_MULTI, also OR in a pointer to a CPU bitmap.   */
364/* UVMF_LOCAL is merely UVMF_MULTI with a NULL bitmap pointer.         */
365#define UVMF_NONE               (0UL<<0) /* No flushing at all.   */
366#define UVMF_TLB_FLUSH          (1UL<<0) /* Flush entire TLB(s).  */
367#define UVMF_INVLPG             (2UL<<0) /* Flush only one entry. */
368#define UVMF_FLUSHTYPE_MASK     (3UL<<0)
369#define UVMF_MULTI              (0UL<<2) /* Flush subset of TLBs. */
370#define UVMF_LOCAL              (0UL<<2) /* Flush local TLB.      */
371#define UVMF_ALL                (1UL<<2) /* Flush all TLBs.       */
372
373/*
374 * Commands to HYPERVISOR_console_io().
375 */
376#define CONSOLEIO_write         0
377#define CONSOLEIO_read          1
378
379/*
380 * Commands to HYPERVISOR_vm_assist().
381 */
382#define VMASST_CMD_enable                0
383#define VMASST_CMD_disable               1
384
385/* x86/32 guests: simulate full 4GB segment limits. */
386#define VMASST_TYPE_4gb_segments         0
387
388/* x86/32 guests: trap (vector 15) whenever above vmassist is used. */
389#define VMASST_TYPE_4gb_segments_notify  1
390
391/*
392 * x86 guests: support writes to bottom-level PTEs.
393 * NB1. Page-directory entries cannot be written.
394 * NB2. Guest must continue to remove all writable mappings of PTEs.
395 */
396#define VMASST_TYPE_writable_pagetables  2
397
398/* x86/PAE guests: support PDPTs above 4GB. */
399#define VMASST_TYPE_pae_extended_cr3     3
400
401/*
402 * x86 guests: Sane behaviour for virtual iopl
403 *  - virtual iopl updated from do_iret() hypercalls.
404 *  - virtual iopl reported in bounce frames.
405 *  - guest kernels assumed to be level 0 for the purpose of iopl checks.
406 */
407#define VMASST_TYPE_architectural_iopl   4
408
409/*
410 * All guests: activate update indicator in vcpu_runstate_info
411 * Enable setting the XEN_RUNSTATE_UPDATE flag in guest memory mapped
412 * vcpu_runstate_info during updates of the runstate information.
413 */
414#define VMASST_TYPE_runstate_update_flag 5
415
416#define MAX_VMASST_TYPE 5
417
418#ifndef __ASSEMBLY__
419
420typedef uint16_t domid_t;
421
422/* Domain ids >= DOMID_FIRST_RESERVED cannot be used for ordinary domains. */
423#define DOMID_FIRST_RESERVED (0x7FF0U)
424
425/* DOMID_SELF is used in certain contexts to refer to oneself. */
426#define DOMID_SELF (0x7FF0U)
427
428/*
429 * DOMID_IO is used to restrict page-table updates to mapping I/O memory.
430 * Although no Foreign Domain need be specified to map I/O pages, DOMID_IO
431 * is useful to ensure that no mappings to the OS's own heap are accidentally
432 * installed. (e.g., in Linux this could cause havoc as reference counts
433 * aren't adjusted on the I/O-mapping code path).
434 * This only makes sense in MMUEXT_SET_FOREIGNDOM, but in that context can
435 * be specified by any calling domain.
436 */
437#define DOMID_IO   (0x7FF1U)
438
439/*
440 * DOMID_XEN is used to allow privileged domains to map restricted parts of
441 * Xen's heap space (e.g., the machine_to_phys table).
442 * This only makes sense in MMUEXT_SET_FOREIGNDOM, and is only permitted if
443 * the caller is privileged.
444 */
445#define DOMID_XEN  (0x7FF2U)
446
447/* DOMID_COW is used as the owner of sharable pages */
448#define DOMID_COW  (0x7FF3U)
449
450/* DOMID_INVALID is used to identify pages with unknown owner. */
451#define DOMID_INVALID (0x7FF4U)
452
453/* Idle domain. */
454#define DOMID_IDLE (0x7FFFU)
455
456/*
457 * Send an array of these to HYPERVISOR_mmu_update().
458 * NB. The fields are natural pointer/address size for this architecture.
459 */
460struct mmu_update {
461    uint64_t ptr;       /* Machine address of PTE. */
462    uint64_t val;       /* New contents of PTE.    */
463};
464DEFINE_GUEST_HANDLE_STRUCT(mmu_update);
465
466/*
467 * Send an array of these to HYPERVISOR_multicall().
468 * NB. The fields are logically the natural register size for this
469 * architecture. In cases where xen_ulong_t is larger than this then
470 * any unused bits in the upper portion must be zero.
471 */
472struct multicall_entry {
473    xen_ulong_t op;
474    xen_long_t result;
475    xen_ulong_t args[6];
476};
477DEFINE_GUEST_HANDLE_STRUCT(multicall_entry);
478
479struct vcpu_time_info {
480	/*
481	 * Updates to the following values are preceded and followed
482	 * by an increment of 'version'. The guest can therefore
483	 * detect updates by looking for changes to 'version'. If the
484	 * least-significant bit of the version number is set then an
485	 * update is in progress and the guest must wait to read a
486	 * consistent set of values.  The correct way to interact with
487	 * the version number is similar to Linux's seqlock: see the
488	 * implementations of read_seqbegin/read_seqretry.
489	 */
490	uint32_t version;
491	uint32_t pad0;
492	uint64_t tsc_timestamp;   /* TSC at last update of time vals.  */
493	uint64_t system_time;     /* Time, in nanosecs, since boot.    */
494	/*
495	 * Current system time:
496	 *   system_time + ((tsc - tsc_timestamp) << tsc_shift) * tsc_to_system_mul
497	 * CPU frequency (Hz):
498	 *   ((10^9 << 32) / tsc_to_system_mul) >> tsc_shift
499	 */
500	uint32_t tsc_to_system_mul;
501	int8_t   tsc_shift;
502	int8_t   pad1[3];
503}; /* 32 bytes */
504
505struct vcpu_info {
506	/*
507	 * 'evtchn_upcall_pending' is written non-zero by Xen to indicate
508	 * a pending notification for a particular VCPU. It is then cleared
509	 * by the guest OS /before/ checking for pending work, thus avoiding
510	 * a set-and-check race. Note that the mask is only accessed by Xen
511	 * on the CPU that is currently hosting the VCPU. This means that the
512	 * pending and mask flags can be updated by the guest without special
513	 * synchronisation (i.e., no need for the x86 LOCK prefix).
514	 * This may seem suboptimal because if the pending flag is set by
515	 * a different CPU then an IPI may be scheduled even when the mask
516	 * is set. However, note:
517	 *  1. The task of 'interrupt holdoff' is covered by the per-event-
518	 *     channel mask bits. A 'noisy' event that is continually being
519	 *     triggered can be masked at source at this very precise
520	 *     granularity.
521	 *  2. The main purpose of the per-VCPU mask is therefore to restrict
522	 *     reentrant execution: whether for concurrency control, or to
523	 *     prevent unbounded stack usage. Whatever the purpose, we expect
524	 *     that the mask will be asserted only for short periods at a time,
525	 *     and so the likelihood of a 'spurious' IPI is suitably small.
526	 * The mask is read before making an event upcall to the guest: a
527	 * non-zero mask therefore guarantees that the VCPU will not receive
528	 * an upcall activation. The mask is cleared when the VCPU requests
529	 * to block: this avoids wakeup-waiting races.
530	 */
531	uint8_t evtchn_upcall_pending;
532	uint8_t evtchn_upcall_mask;
533	xen_ulong_t evtchn_pending_sel;
534	struct arch_vcpu_info arch;
535	struct pvclock_vcpu_time_info time;
536}; /* 64 bytes (x86) */
537
538/*
539 * Xen/kernel shared data -- pointer provided in start_info.
540 * NB. We expect that this struct is smaller than a page.
541 */
542struct shared_info {
543	struct vcpu_info vcpu_info[MAX_VIRT_CPUS];
544
545	/*
546	 * A domain can create "event channels" on which it can send and receive
547	 * asynchronous event notifications. There are three classes of event that
548	 * are delivered by this mechanism:
549	 *  1. Bi-directional inter- and intra-domain connections. Domains must
550	 *     arrange out-of-band to set up a connection (usually by allocating
551	 *     an unbound 'listener' port and avertising that via a storage service
552	 *     such as xenstore).
553	 *  2. Physical interrupts. A domain with suitable hardware-access
554	 *     privileges can bind an event-channel port to a physical interrupt
555	 *     source.
556	 *  3. Virtual interrupts ('events'). A domain can bind an event-channel
557	 *     port to a virtual interrupt source, such as the virtual-timer
558	 *     device or the emergency console.
559	 *
560	 * Event channels are addressed by a "port index". Each channel is
561	 * associated with two bits of information:
562	 *  1. PENDING -- notifies the domain that there is a pending notification
563	 *     to be processed. This bit is cleared by the guest.
564	 *  2. MASK -- if this bit is clear then a 0->1 transition of PENDING
565	 *     will cause an asynchronous upcall to be scheduled. This bit is only
566	 *     updated by the guest. It is read-only within Xen. If a channel
567	 *     becomes pending while the channel is masked then the 'edge' is lost
568	 *     (i.e., when the channel is unmasked, the guest must manually handle
569	 *     pending notifications as no upcall will be scheduled by Xen).
570	 *
571	 * To expedite scanning of pending notifications, any 0->1 pending
572	 * transition on an unmasked channel causes a corresponding bit in a
573	 * per-vcpu selector word to be set. Each bit in the selector covers a
574	 * 'C long' in the PENDING bitfield array.
575	 */
576	xen_ulong_t evtchn_pending[sizeof(xen_ulong_t) * 8];
577	xen_ulong_t evtchn_mask[sizeof(xen_ulong_t) * 8];
578
579	/*
580	 * Wallclock time: updated only by control software. Guests should base
581	 * their gettimeofday() syscall on this wallclock-base value.
582	 */
583	struct pvclock_wall_clock wc;
584#ifndef CONFIG_X86_32
585	uint32_t wc_sec_hi;
586#endif
587	struct arch_shared_info arch;
588
589};
590
591/*
592 * Start-of-day memory layout
593 *
594 *  1. The domain is started within contiguous virtual-memory region.
595 *  2. The contiguous region begins and ends on an aligned 4MB boundary.
596 *  3. This the order of bootstrap elements in the initial virtual region:
597 *      a. relocated kernel image
598 *      b. initial ram disk              [mod_start, mod_len]
599 *         (may be omitted)
600 *      c. list of allocated page frames [mfn_list, nr_pages]
601 *         (unless relocated due to XEN_ELFNOTE_INIT_P2M)
602 *      d. start_info_t structure        [register ESI (x86)]
603 *         in case of dom0 this page contains the console info, too
604 *      e. unless dom0: xenstore ring page
605 *      f. unless dom0: console ring page
606 *      g. bootstrap page tables         [pt_base, CR3 (x86)]
607 *      h. bootstrap stack               [register ESP (x86)]
608 *  4. Bootstrap elements are packed together, but each is 4kB-aligned.
609 *  5. The list of page frames forms a contiguous 'pseudo-physical' memory
610 *     layout for the domain. In particular, the bootstrap virtual-memory
611 *     region is a 1:1 mapping to the first section of the pseudo-physical map.
612 *  6. All bootstrap elements are mapped read-writable for the guest OS. The
613 *     only exception is the bootstrap page table, which is mapped read-only.
614 *  7. There is guaranteed to be at least 512kB padding after the final
615 *     bootstrap element. If necessary, the bootstrap virtual region is
616 *     extended by an extra 4MB to ensure this.
617 */
618
619#define MAX_GUEST_CMDLINE 1024
620struct start_info {
621	/* THE FOLLOWING ARE FILLED IN BOTH ON INITIAL BOOT AND ON RESUME.    */
622	char magic[32];             /* "xen-<version>-<platform>".            */
623	unsigned long nr_pages;     /* Total pages allocated to this domain.  */
624	unsigned long shared_info;  /* MACHINE address of shared info struct. */
625	uint32_t flags;             /* SIF_xxx flags.                         */
626	xen_pfn_t store_mfn;        /* MACHINE page number of shared page.    */
627	uint32_t store_evtchn;      /* Event channel for store communication. */
628	union {
629		struct {
630			xen_pfn_t mfn;      /* MACHINE page number of console page.   */
631			uint32_t  evtchn;   /* Event channel for console page.        */
632		} domU;
633		struct {
634			uint32_t info_off;  /* Offset of console_info struct.         */
635			uint32_t info_size; /* Size of console_info struct from start.*/
636		} dom0;
637	} console;
638	/* THE FOLLOWING ARE ONLY FILLED IN ON INITIAL BOOT (NOT RESUME).     */
639	unsigned long pt_base;      /* VIRTUAL address of page directory.     */
640	unsigned long nr_pt_frames; /* Number of bootstrap p.t. frames.       */
641	unsigned long mfn_list;     /* VIRTUAL address of page-frame list.    */
642	unsigned long mod_start;    /* VIRTUAL address of pre-loaded module.  */
643	unsigned long mod_len;      /* Size (bytes) of pre-loaded module.     */
644	int8_t cmd_line[MAX_GUEST_CMDLINE];
645	/* The pfn range here covers both page table and p->m table frames.   */
646	unsigned long first_p2m_pfn;/* 1st pfn forming initial P->M table.    */
647	unsigned long nr_p2m_frames;/* # of pfns forming initial P->M table.  */
648};
649
650/* These flags are passed in the 'flags' field of start_info_t. */
651#define SIF_PRIVILEGED      (1<<0)  /* Is the domain privileged? */
652#define SIF_INITDOMAIN      (1<<1)  /* Is this the initial control domain? */
653#define SIF_MULTIBOOT_MOD   (1<<2)  /* Is mod_start a multiboot module? */
654#define SIF_MOD_START_PFN   (1<<3)  /* Is mod_start a PFN? */
655#define SIF_VIRT_P2M_4TOOLS (1<<4)  /* Do Xen tools understand a virt. mapped */
656				    /* P->M making the 3 level tree obsolete? */
657#define SIF_PM_MASK       (0xFF<<8) /* reserve 1 byte for xen-pm options */
658
659/*
660 * A multiboot module is a package containing modules very similar to a
661 * multiboot module array. The only differences are:
662 * - the array of module descriptors is by convention simply at the beginning
663 *   of the multiboot module,
664 * - addresses in the module descriptors are based on the beginning of the
665 *   multiboot module,
666 * - the number of modules is determined by a termination descriptor that has
667 *   mod_start == 0.
668 *
669 * This permits to both build it statically and reference it in a configuration
670 * file, and let the PV guest easily rebase the addresses to virtual addresses
671 * and at the same time count the number of modules.
672 */
673struct xen_multiboot_mod_list {
674	/* Address of first byte of the module */
675	uint32_t mod_start;
676	/* Address of last byte of the module (inclusive) */
677	uint32_t mod_end;
678	/* Address of zero-terminated command line */
679	uint32_t cmdline;
680	/* Unused, must be zero */
681	uint32_t pad;
682};
683/*
684 * The console structure in start_info.console.dom0
685 *
686 * This structure includes a variety of information required to
687 * have a working VGA/VESA console.
688 */
689struct dom0_vga_console_info {
690	uint8_t video_type;
691#define XEN_VGATYPE_TEXT_MODE_3 0x03
692#define XEN_VGATYPE_VESA_LFB    0x23
693#define XEN_VGATYPE_EFI_LFB     0x70
694
695	union {
696		struct {
697			/* Font height, in pixels. */
698			uint16_t font_height;
699			/* Cursor location (column, row). */
700			uint16_t cursor_x, cursor_y;
701			/* Number of rows and columns (dimensions in characters). */
702			uint16_t rows, columns;
703		} text_mode_3;
704
705		struct {
706			/* Width and height, in pixels. */
707			uint16_t width, height;
708			/* Bytes per scan line. */
709			uint16_t bytes_per_line;
710			/* Bits per pixel. */
711			uint16_t bits_per_pixel;
712			/* LFB physical address, and size (in units of 64kB). */
713			uint32_t lfb_base;
714			uint32_t lfb_size;
715			/* RGB mask offsets and sizes, as defined by VBE 1.2+ */
716			uint8_t  red_pos, red_size;
717			uint8_t  green_pos, green_size;
718			uint8_t  blue_pos, blue_size;
719			uint8_t  rsvd_pos, rsvd_size;
720
721			/* VESA capabilities (offset 0xa, VESA command 0x4f00). */
722			uint32_t gbl_caps;
723			/* Mode attributes (offset 0x0, VESA command 0x4f01). */
724			uint16_t mode_attrs;
725			uint16_t pad;
726			/* high 32 bits of lfb_base */
727			uint32_t ext_lfb_base;
728		} vesa_lfb;
729	} u;
730};
731
732typedef uint64_t cpumap_t;
733
734typedef uint8_t xen_domain_handle_t[16];
735
736/* Turn a plain number into a C unsigned long constant. */
737#define __mk_unsigned_long(x) x ## UL
738#define mk_unsigned_long(x) __mk_unsigned_long(x)
739
740#define TMEM_SPEC_VERSION 1
741
742struct tmem_op {
743	uint32_t cmd;
744	int32_t pool_id;
745	union {
746		struct {  /* for cmd == TMEM_NEW_POOL */
747			uint64_t uuid[2];
748			uint32_t flags;
749		} new;
750		struct {
751			uint64_t oid[3];
752			uint32_t index;
753			uint32_t tmem_offset;
754			uint32_t pfn_offset;
755			uint32_t len;
756			GUEST_HANDLE(void) gmfn; /* guest machine page frame */
757		} gen;
758	} u;
759};
760
761DEFINE_GUEST_HANDLE(u64);
762
763#else /* __ASSEMBLY__ */
764
765/* In assembly code we cannot use C numeric constant suffixes. */
766#define mk_unsigned_long(x) x
767
768#endif /* !__ASSEMBLY__ */
769
770#endif /* __XEN_PUBLIC_XEN_H__ */
771