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__
341 struct 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 };
359 DEFINE_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
420 typedef 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 */
460 struct mmu_update {
461 uint64_t ptr; /* Machine address of PTE. */
462 uint64_t val; /* New contents of PTE. */
463 };
464 DEFINE_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 */
472 struct multicall_entry {
473 xen_ulong_t op;
474 xen_long_t result;
475 xen_ulong_t args[6];
476 };
477 DEFINE_GUEST_HANDLE_STRUCT(multicall_entry);
478
479 struct 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
505 struct 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 */
542 struct 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
620 struct 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 */
673 struct 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 */
689 struct 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
732 typedef uint64_t cpumap_t;
733
734 typedef 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
742 struct 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
761 DEFINE_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
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