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e1dab14c VK |
1 | /* |
2 | * Core of Xen paravirt_ops implementation. | |
3 | * | |
4 | * This file contains the xen_paravirt_ops structure itself, and the | |
5 | * implementations for: | |
6 | * - privileged instructions | |
7 | * - interrupt flags | |
8 | * - segment operations | |
9 | * - booting and setup | |
10 | * | |
11 | * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 | |
12 | */ | |
13 | ||
14 | #include <linux/cpu.h> | |
15 | #include <linux/kernel.h> | |
16 | #include <linux/init.h> | |
17 | #include <linux/smp.h> | |
18 | #include <linux/preempt.h> | |
19 | #include <linux/hardirq.h> | |
20 | #include <linux/percpu.h> | |
21 | #include <linux/delay.h> | |
22 | #include <linux/start_kernel.h> | |
23 | #include <linux/sched.h> | |
24 | #include <linux/kprobes.h> | |
25 | #include <linux/bootmem.h> | |
26 | #include <linux/export.h> | |
27 | #include <linux/mm.h> | |
28 | #include <linux/page-flags.h> | |
29 | #include <linux/highmem.h> | |
30 | #include <linux/console.h> | |
31 | #include <linux/pci.h> | |
32 | #include <linux/gfp.h> | |
33 | #include <linux/memblock.h> | |
34 | #include <linux/edd.h> | |
35 | #include <linux/frame.h> | |
36 | ||
37 | #include <xen/xen.h> | |
38 | #include <xen/events.h> | |
39 | #include <xen/interface/xen.h> | |
40 | #include <xen/interface/version.h> | |
41 | #include <xen/interface/physdev.h> | |
42 | #include <xen/interface/vcpu.h> | |
43 | #include <xen/interface/memory.h> | |
44 | #include <xen/interface/nmi.h> | |
45 | #include <xen/interface/xen-mca.h> | |
46 | #include <xen/features.h> | |
47 | #include <xen/page.h> | |
48 | #include <xen/hvc-console.h> | |
49 | #include <xen/acpi.h> | |
50 | ||
51 | #include <asm/paravirt.h> | |
52 | #include <asm/apic.h> | |
53 | #include <asm/page.h> | |
54 | #include <asm/xen/pci.h> | |
55 | #include <asm/xen/hypercall.h> | |
56 | #include <asm/xen/hypervisor.h> | |
57 | #include <asm/xen/cpuid.h> | |
58 | #include <asm/fixmap.h> | |
59 | #include <asm/processor.h> | |
60 | #include <asm/proto.h> | |
61 | #include <asm/msr-index.h> | |
62 | #include <asm/traps.h> | |
63 | #include <asm/setup.h> | |
64 | #include <asm/desc.h> | |
65 | #include <asm/pgalloc.h> | |
66 | #include <asm/pgtable.h> | |
67 | #include <asm/tlbflush.h> | |
68 | #include <asm/reboot.h> | |
69 | #include <asm/stackprotector.h> | |
70 | #include <asm/hypervisor.h> | |
71 | #include <asm/mach_traps.h> | |
72 | #include <asm/mwait.h> | |
73 | #include <asm/pci_x86.h> | |
74 | #include <asm/cpu.h> | |
75 | ||
76 | #ifdef CONFIG_ACPI | |
77 | #include <linux/acpi.h> | |
78 | #include <asm/acpi.h> | |
79 | #include <acpi/pdc_intel.h> | |
80 | #include <acpi/processor.h> | |
81 | #include <xen/interface/platform.h> | |
82 | #endif | |
83 | ||
84 | #include "xen-ops.h" | |
85 | #include "mmu.h" | |
86 | #include "smp.h" | |
87 | #include "multicalls.h" | |
88 | #include "pmu.h" | |
89 | ||
90 | void *xen_initial_gdt; | |
91 | ||
e1dab14c VK |
92 | static int xen_cpu_up_prepare_pv(unsigned int cpu); |
93 | static int xen_cpu_dead_pv(unsigned int cpu); | |
94 | ||
95 | struct tls_descs { | |
96 | struct desc_struct desc[3]; | |
97 | }; | |
98 | ||
99 | /* | |
100 | * Updating the 3 TLS descriptors in the GDT on every task switch is | |
101 | * surprisingly expensive so we avoid updating them if they haven't | |
102 | * changed. Since Xen writes different descriptors than the one | |
103 | * passed in the update_descriptor hypercall we keep shadow copies to | |
104 | * compare against. | |
105 | */ | |
106 | static DEFINE_PER_CPU(struct tls_descs, shadow_tls_desc); | |
107 | ||
e1dab14c VK |
108 | static void __init xen_banner(void) |
109 | { | |
110 | unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL); | |
111 | struct xen_extraversion extra; | |
112 | HYPERVISOR_xen_version(XENVER_extraversion, &extra); | |
113 | ||
989513a7 | 114 | pr_info("Booting paravirtualized kernel on %s\n", pv_info.name); |
e1dab14c VK |
115 | printk(KERN_INFO "Xen version: %d.%d%s%s\n", |
116 | version >> 16, version & 0xffff, extra.extraversion, | |
117 | xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : ""); | |
118 | } | |
119 | /* Check if running on Xen version (major, minor) or later */ | |
120 | bool | |
121 | xen_running_on_version_or_later(unsigned int major, unsigned int minor) | |
122 | { | |
123 | unsigned int version; | |
124 | ||
125 | if (!xen_domain()) | |
126 | return false; | |
127 | ||
128 | version = HYPERVISOR_xen_version(XENVER_version, NULL); | |
129 | if ((((version >> 16) == major) && ((version & 0xffff) >= minor)) || | |
130 | ((version >> 16) > major)) | |
131 | return true; | |
132 | return false; | |
133 | } | |
134 | ||
e1dab14c VK |
135 | static __read_mostly unsigned int cpuid_leaf5_ecx_val; |
136 | static __read_mostly unsigned int cpuid_leaf5_edx_val; | |
137 | ||
138 | static void xen_cpuid(unsigned int *ax, unsigned int *bx, | |
139 | unsigned int *cx, unsigned int *dx) | |
140 | { | |
141 | unsigned maskebx = ~0; | |
6807cf65 | 142 | |
e1dab14c VK |
143 | /* |
144 | * Mask out inconvenient features, to try and disable as many | |
145 | * unsupported kernel subsystems as possible. | |
146 | */ | |
147 | switch (*ax) { | |
e1dab14c VK |
148 | case CPUID_MWAIT_LEAF: |
149 | /* Synthesize the values.. */ | |
150 | *ax = 0; | |
151 | *bx = 0; | |
152 | *cx = cpuid_leaf5_ecx_val; | |
153 | *dx = cpuid_leaf5_edx_val; | |
154 | return; | |
155 | ||
e1dab14c VK |
156 | case 0xb: |
157 | /* Suppress extended topology stuff */ | |
158 | maskebx = 0; | |
159 | break; | |
160 | } | |
161 | ||
162 | asm(XEN_EMULATE_PREFIX "cpuid" | |
163 | : "=a" (*ax), | |
164 | "=b" (*bx), | |
165 | "=c" (*cx), | |
166 | "=d" (*dx) | |
167 | : "0" (*ax), "2" (*cx)); | |
168 | ||
169 | *bx &= maskebx; | |
e1dab14c VK |
170 | } |
171 | STACK_FRAME_NON_STANDARD(xen_cpuid); /* XEN_EMULATE_PREFIX */ | |
172 | ||
173 | static bool __init xen_check_mwait(void) | |
174 | { | |
175 | #ifdef CONFIG_ACPI | |
176 | struct xen_platform_op op = { | |
177 | .cmd = XENPF_set_processor_pminfo, | |
178 | .u.set_pminfo.id = -1, | |
179 | .u.set_pminfo.type = XEN_PM_PDC, | |
180 | }; | |
181 | uint32_t buf[3]; | |
182 | unsigned int ax, bx, cx, dx; | |
183 | unsigned int mwait_mask; | |
184 | ||
185 | /* We need to determine whether it is OK to expose the MWAIT | |
186 | * capability to the kernel to harvest deeper than C3 states from ACPI | |
187 | * _CST using the processor_harvest_xen.c module. For this to work, we | |
188 | * need to gather the MWAIT_LEAF values (which the cstate.c code | |
189 | * checks against). The hypervisor won't expose the MWAIT flag because | |
190 | * it would break backwards compatibility; so we will find out directly | |
191 | * from the hardware and hypercall. | |
192 | */ | |
193 | if (!xen_initial_domain()) | |
194 | return false; | |
195 | ||
196 | /* | |
197 | * When running under platform earlier than Xen4.2, do not expose | |
198 | * mwait, to avoid the risk of loading native acpi pad driver | |
199 | */ | |
200 | if (!xen_running_on_version_or_later(4, 2)) | |
201 | return false; | |
202 | ||
203 | ax = 1; | |
204 | cx = 0; | |
205 | ||
206 | native_cpuid(&ax, &bx, &cx, &dx); | |
207 | ||
208 | mwait_mask = (1 << (X86_FEATURE_EST % 32)) | | |
209 | (1 << (X86_FEATURE_MWAIT % 32)); | |
210 | ||
211 | if ((cx & mwait_mask) != mwait_mask) | |
212 | return false; | |
213 | ||
214 | /* We need to emulate the MWAIT_LEAF and for that we need both | |
215 | * ecx and edx. The hypercall provides only partial information. | |
216 | */ | |
217 | ||
218 | ax = CPUID_MWAIT_LEAF; | |
219 | bx = 0; | |
220 | cx = 0; | |
221 | dx = 0; | |
222 | ||
223 | native_cpuid(&ax, &bx, &cx, &dx); | |
224 | ||
225 | /* Ask the Hypervisor whether to clear ACPI_PDC_C_C2C3_FFH. If so, | |
226 | * don't expose MWAIT_LEAF and let ACPI pick the IOPORT version of C3. | |
227 | */ | |
228 | buf[0] = ACPI_PDC_REVISION_ID; | |
229 | buf[1] = 1; | |
230 | buf[2] = (ACPI_PDC_C_CAPABILITY_SMP | ACPI_PDC_EST_CAPABILITY_SWSMP); | |
231 | ||
232 | set_xen_guest_handle(op.u.set_pminfo.pdc, buf); | |
233 | ||
234 | if ((HYPERVISOR_platform_op(&op) == 0) && | |
235 | (buf[2] & (ACPI_PDC_C_C1_FFH | ACPI_PDC_C_C2C3_FFH))) { | |
236 | cpuid_leaf5_ecx_val = cx; | |
237 | cpuid_leaf5_edx_val = dx; | |
238 | } | |
239 | return true; | |
240 | #else | |
241 | return false; | |
242 | #endif | |
243 | } | |
e1dab14c | 244 | |
6807cf65 JG |
245 | static bool __init xen_check_xsave(void) |
246 | { | |
40f4ac0b | 247 | unsigned int cx, xsave_mask; |
e1dab14c | 248 | |
40f4ac0b JG |
249 | cx = cpuid_ecx(1); |
250 | ||
251 | xsave_mask = (1 << (X86_FEATURE_XSAVE % 32)) | | |
252 | (1 << (X86_FEATURE_OSXSAVE % 32)); | |
253 | ||
254 | /* Xen will set CR4.OSXSAVE if supported and not disabled by force */ | |
255 | return (cx & xsave_mask) == xsave_mask; | |
e1dab14c VK |
256 | } |
257 | ||
0808e80c JG |
258 | static void __init xen_init_capabilities(void) |
259 | { | |
0808e80c | 260 | setup_force_cpu_cap(X86_FEATURE_XENPV); |
3ee99df3 | 261 | setup_clear_cpu_cap(X86_FEATURE_DCA); |
fd9145fd | 262 | setup_clear_cpu_cap(X86_FEATURE_APERFMPERF); |
88f3256f | 263 | setup_clear_cpu_cap(X86_FEATURE_MTRR); |
aa107156 | 264 | setup_clear_cpu_cap(X86_FEATURE_ACC); |
e657fccb | 265 | setup_clear_cpu_cap(X86_FEATURE_X2APIC); |
b778d6bf JG |
266 | |
267 | if (!xen_initial_domain()) | |
268 | setup_clear_cpu_cap(X86_FEATURE_ACPI); | |
ea01598b JG |
269 | |
270 | if (xen_check_mwait()) | |
271 | setup_force_cpu_cap(X86_FEATURE_MWAIT); | |
272 | else | |
273 | setup_clear_cpu_cap(X86_FEATURE_MWAIT); | |
6807cf65 | 274 | |
40f4ac0b | 275 | if (!xen_check_xsave()) { |
6807cf65 JG |
276 | setup_clear_cpu_cap(X86_FEATURE_XSAVE); |
277 | setup_clear_cpu_cap(X86_FEATURE_OSXSAVE); | |
278 | } | |
0808e80c JG |
279 | } |
280 | ||
e1dab14c VK |
281 | static void xen_set_debugreg(int reg, unsigned long val) |
282 | { | |
283 | HYPERVISOR_set_debugreg(reg, val); | |
284 | } | |
285 | ||
286 | static unsigned long xen_get_debugreg(int reg) | |
287 | { | |
288 | return HYPERVISOR_get_debugreg(reg); | |
289 | } | |
290 | ||
291 | static void xen_end_context_switch(struct task_struct *next) | |
292 | { | |
293 | xen_mc_flush(); | |
294 | paravirt_end_context_switch(next); | |
295 | } | |
296 | ||
297 | static unsigned long xen_store_tr(void) | |
298 | { | |
299 | return 0; | |
300 | } | |
301 | ||
302 | /* | |
303 | * Set the page permissions for a particular virtual address. If the | |
304 | * address is a vmalloc mapping (or other non-linear mapping), then | |
305 | * find the linear mapping of the page and also set its protections to | |
306 | * match. | |
307 | */ | |
308 | static void set_aliased_prot(void *v, pgprot_t prot) | |
309 | { | |
310 | int level; | |
311 | pte_t *ptep; | |
312 | pte_t pte; | |
313 | unsigned long pfn; | |
314 | struct page *page; | |
315 | unsigned char dummy; | |
316 | ||
317 | ptep = lookup_address((unsigned long)v, &level); | |
318 | BUG_ON(ptep == NULL); | |
319 | ||
320 | pfn = pte_pfn(*ptep); | |
321 | page = pfn_to_page(pfn); | |
322 | ||
323 | pte = pfn_pte(pfn, prot); | |
324 | ||
325 | /* | |
326 | * Careful: update_va_mapping() will fail if the virtual address | |
327 | * we're poking isn't populated in the page tables. We don't | |
328 | * need to worry about the direct map (that's always in the page | |
329 | * tables), but we need to be careful about vmap space. In | |
330 | * particular, the top level page table can lazily propagate | |
331 | * entries between processes, so if we've switched mms since we | |
332 | * vmapped the target in the first place, we might not have the | |
333 | * top-level page table entry populated. | |
334 | * | |
335 | * We disable preemption because we want the same mm active when | |
336 | * we probe the target and when we issue the hypercall. We'll | |
337 | * have the same nominal mm, but if we're a kernel thread, lazy | |
338 | * mm dropping could change our pgd. | |
339 | * | |
340 | * Out of an abundance of caution, this uses __get_user() to fault | |
341 | * in the target address just in case there's some obscure case | |
342 | * in which the target address isn't readable. | |
343 | */ | |
344 | ||
345 | preempt_disable(); | |
346 | ||
347 | probe_kernel_read(&dummy, v, 1); | |
348 | ||
349 | if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0)) | |
350 | BUG(); | |
351 | ||
352 | if (!PageHighMem(page)) { | |
353 | void *av = __va(PFN_PHYS(pfn)); | |
354 | ||
355 | if (av != v) | |
356 | if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0)) | |
357 | BUG(); | |
358 | } else | |
359 | kmap_flush_unused(); | |
360 | ||
361 | preempt_enable(); | |
362 | } | |
363 | ||
364 | static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries) | |
365 | { | |
366 | const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE; | |
367 | int i; | |
368 | ||
369 | /* | |
370 | * We need to mark the all aliases of the LDT pages RO. We | |
371 | * don't need to call vm_flush_aliases(), though, since that's | |
372 | * only responsible for flushing aliases out the TLBs, not the | |
373 | * page tables, and Xen will flush the TLB for us if needed. | |
374 | * | |
375 | * To avoid confusing future readers: none of this is necessary | |
376 | * to load the LDT. The hypervisor only checks this when the | |
377 | * LDT is faulted in due to subsequent descriptor access. | |
378 | */ | |
379 | ||
380 | for (i = 0; i < entries; i += entries_per_page) | |
381 | set_aliased_prot(ldt + i, PAGE_KERNEL_RO); | |
382 | } | |
383 | ||
384 | static void xen_free_ldt(struct desc_struct *ldt, unsigned entries) | |
385 | { | |
386 | const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE; | |
387 | int i; | |
388 | ||
389 | for (i = 0; i < entries; i += entries_per_page) | |
390 | set_aliased_prot(ldt + i, PAGE_KERNEL); | |
391 | } | |
392 | ||
393 | static void xen_set_ldt(const void *addr, unsigned entries) | |
394 | { | |
395 | struct mmuext_op *op; | |
396 | struct multicall_space mcs = xen_mc_entry(sizeof(*op)); | |
397 | ||
398 | trace_xen_cpu_set_ldt(addr, entries); | |
399 | ||
400 | op = mcs.args; | |
401 | op->cmd = MMUEXT_SET_LDT; | |
402 | op->arg1.linear_addr = (unsigned long)addr; | |
403 | op->arg2.nr_ents = entries; | |
404 | ||
405 | MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); | |
406 | ||
407 | xen_mc_issue(PARAVIRT_LAZY_CPU); | |
408 | } | |
409 | ||
410 | static void xen_load_gdt(const struct desc_ptr *dtr) | |
411 | { | |
412 | unsigned long va = dtr->address; | |
413 | unsigned int size = dtr->size + 1; | |
414 | unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE); | |
415 | unsigned long frames[pages]; | |
416 | int f; | |
417 | ||
418 | /* | |
419 | * A GDT can be up to 64k in size, which corresponds to 8192 | |
420 | * 8-byte entries, or 16 4k pages.. | |
421 | */ | |
422 | ||
423 | BUG_ON(size > 65536); | |
424 | BUG_ON(va & ~PAGE_MASK); | |
425 | ||
426 | for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) { | |
427 | int level; | |
428 | pte_t *ptep; | |
429 | unsigned long pfn, mfn; | |
430 | void *virt; | |
431 | ||
432 | /* | |
433 | * The GDT is per-cpu and is in the percpu data area. | |
434 | * That can be virtually mapped, so we need to do a | |
435 | * page-walk to get the underlying MFN for the | |
436 | * hypercall. The page can also be in the kernel's | |
437 | * linear range, so we need to RO that mapping too. | |
438 | */ | |
439 | ptep = lookup_address(va, &level); | |
440 | BUG_ON(ptep == NULL); | |
441 | ||
442 | pfn = pte_pfn(*ptep); | |
443 | mfn = pfn_to_mfn(pfn); | |
444 | virt = __va(PFN_PHYS(pfn)); | |
445 | ||
446 | frames[f] = mfn; | |
447 | ||
448 | make_lowmem_page_readonly((void *)va); | |
449 | make_lowmem_page_readonly(virt); | |
450 | } | |
451 | ||
452 | if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct))) | |
453 | BUG(); | |
454 | } | |
455 | ||
456 | /* | |
457 | * load_gdt for early boot, when the gdt is only mapped once | |
458 | */ | |
459 | static void __init xen_load_gdt_boot(const struct desc_ptr *dtr) | |
460 | { | |
461 | unsigned long va = dtr->address; | |
462 | unsigned int size = dtr->size + 1; | |
463 | unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE); | |
464 | unsigned long frames[pages]; | |
465 | int f; | |
466 | ||
467 | /* | |
468 | * A GDT can be up to 64k in size, which corresponds to 8192 | |
469 | * 8-byte entries, or 16 4k pages.. | |
470 | */ | |
471 | ||
472 | BUG_ON(size > 65536); | |
473 | BUG_ON(va & ~PAGE_MASK); | |
474 | ||
475 | for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) { | |
476 | pte_t pte; | |
477 | unsigned long pfn, mfn; | |
478 | ||
479 | pfn = virt_to_pfn(va); | |
480 | mfn = pfn_to_mfn(pfn); | |
481 | ||
482 | pte = pfn_pte(pfn, PAGE_KERNEL_RO); | |
483 | ||
484 | if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0)) | |
485 | BUG(); | |
486 | ||
487 | frames[f] = mfn; | |
488 | } | |
489 | ||
490 | if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct))) | |
491 | BUG(); | |
492 | } | |
493 | ||
494 | static inline bool desc_equal(const struct desc_struct *d1, | |
495 | const struct desc_struct *d2) | |
496 | { | |
497 | return d1->a == d2->a && d1->b == d2->b; | |
498 | } | |
499 | ||
500 | static void load_TLS_descriptor(struct thread_struct *t, | |
501 | unsigned int cpu, unsigned int i) | |
502 | { | |
503 | struct desc_struct *shadow = &per_cpu(shadow_tls_desc, cpu).desc[i]; | |
504 | struct desc_struct *gdt; | |
505 | xmaddr_t maddr; | |
506 | struct multicall_space mc; | |
507 | ||
508 | if (desc_equal(shadow, &t->tls_array[i])) | |
509 | return; | |
510 | ||
511 | *shadow = t->tls_array[i]; | |
512 | ||
513 | gdt = get_cpu_gdt_rw(cpu); | |
514 | maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]); | |
515 | mc = __xen_mc_entry(0); | |
516 | ||
517 | MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]); | |
518 | } | |
519 | ||
520 | static void xen_load_tls(struct thread_struct *t, unsigned int cpu) | |
521 | { | |
522 | /* | |
523 | * XXX sleazy hack: If we're being called in a lazy-cpu zone | |
524 | * and lazy gs handling is enabled, it means we're in a | |
525 | * context switch, and %gs has just been saved. This means we | |
526 | * can zero it out to prevent faults on exit from the | |
527 | * hypervisor if the next process has no %gs. Either way, it | |
528 | * has been saved, and the new value will get loaded properly. | |
529 | * This will go away as soon as Xen has been modified to not | |
530 | * save/restore %gs for normal hypercalls. | |
531 | * | |
532 | * On x86_64, this hack is not used for %gs, because gs points | |
533 | * to KERNEL_GS_BASE (and uses it for PDA references), so we | |
534 | * must not zero %gs on x86_64 | |
535 | * | |
536 | * For x86_64, we need to zero %fs, otherwise we may get an | |
537 | * exception between the new %fs descriptor being loaded and | |
538 | * %fs being effectively cleared at __switch_to(). | |
539 | */ | |
540 | if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) { | |
541 | #ifdef CONFIG_X86_32 | |
542 | lazy_load_gs(0); | |
543 | #else | |
544 | loadsegment(fs, 0); | |
545 | #endif | |
546 | } | |
547 | ||
548 | xen_mc_batch(); | |
549 | ||
550 | load_TLS_descriptor(t, cpu, 0); | |
551 | load_TLS_descriptor(t, cpu, 1); | |
552 | load_TLS_descriptor(t, cpu, 2); | |
553 | ||
554 | xen_mc_issue(PARAVIRT_LAZY_CPU); | |
555 | } | |
556 | ||
557 | #ifdef CONFIG_X86_64 | |
558 | static void xen_load_gs_index(unsigned int idx) | |
559 | { | |
560 | if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx)) | |
561 | BUG(); | |
562 | } | |
563 | #endif | |
564 | ||
565 | static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, | |
566 | const void *ptr) | |
567 | { | |
568 | xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]); | |
569 | u64 entry = *(u64 *)ptr; | |
570 | ||
571 | trace_xen_cpu_write_ldt_entry(dt, entrynum, entry); | |
572 | ||
573 | preempt_disable(); | |
574 | ||
575 | xen_mc_flush(); | |
576 | if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry)) | |
577 | BUG(); | |
578 | ||
579 | preempt_enable(); | |
580 | } | |
581 | ||
582 | static int cvt_gate_to_trap(int vector, const gate_desc *val, | |
583 | struct trap_info *info) | |
584 | { | |
585 | unsigned long addr; | |
586 | ||
587 | if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT) | |
588 | return 0; | |
589 | ||
590 | info->vector = vector; | |
591 | ||
592 | addr = gate_offset(*val); | |
593 | #ifdef CONFIG_X86_64 | |
594 | /* | |
595 | * Look for known traps using IST, and substitute them | |
596 | * appropriately. The debugger ones are the only ones we care | |
597 | * about. Xen will handle faults like double_fault, | |
598 | * so we should never see them. Warn if | |
599 | * there's an unexpected IST-using fault handler. | |
600 | */ | |
601 | if (addr == (unsigned long)debug) | |
602 | addr = (unsigned long)xen_debug; | |
603 | else if (addr == (unsigned long)int3) | |
604 | addr = (unsigned long)xen_int3; | |
605 | else if (addr == (unsigned long)stack_segment) | |
606 | addr = (unsigned long)xen_stack_segment; | |
607 | else if (addr == (unsigned long)double_fault) { | |
608 | /* Don't need to handle these */ | |
609 | return 0; | |
610 | #ifdef CONFIG_X86_MCE | |
611 | } else if (addr == (unsigned long)machine_check) { | |
612 | /* | |
613 | * when xen hypervisor inject vMCE to guest, | |
614 | * use native mce handler to handle it | |
615 | */ | |
616 | ; | |
617 | #endif | |
618 | } else if (addr == (unsigned long)nmi) | |
619 | /* | |
620 | * Use the native version as well. | |
621 | */ | |
622 | ; | |
623 | else { | |
624 | /* Some other trap using IST? */ | |
625 | if (WARN_ON(val->ist != 0)) | |
626 | return 0; | |
627 | } | |
628 | #endif /* CONFIG_X86_64 */ | |
629 | info->address = addr; | |
630 | ||
631 | info->cs = gate_segment(*val); | |
632 | info->flags = val->dpl; | |
633 | /* interrupt gates clear IF */ | |
634 | if (val->type == GATE_INTERRUPT) | |
635 | info->flags |= 1 << 2; | |
636 | ||
637 | return 1; | |
638 | } | |
639 | ||
640 | /* Locations of each CPU's IDT */ | |
641 | static DEFINE_PER_CPU(struct desc_ptr, idt_desc); | |
642 | ||
643 | /* Set an IDT entry. If the entry is part of the current IDT, then | |
644 | also update Xen. */ | |
645 | static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g) | |
646 | { | |
647 | unsigned long p = (unsigned long)&dt[entrynum]; | |
648 | unsigned long start, end; | |
649 | ||
650 | trace_xen_cpu_write_idt_entry(dt, entrynum, g); | |
651 | ||
652 | preempt_disable(); | |
653 | ||
654 | start = __this_cpu_read(idt_desc.address); | |
655 | end = start + __this_cpu_read(idt_desc.size) + 1; | |
656 | ||
657 | xen_mc_flush(); | |
658 | ||
659 | native_write_idt_entry(dt, entrynum, g); | |
660 | ||
661 | if (p >= start && (p + 8) <= end) { | |
662 | struct trap_info info[2]; | |
663 | ||
664 | info[1].address = 0; | |
665 | ||
666 | if (cvt_gate_to_trap(entrynum, g, &info[0])) | |
667 | if (HYPERVISOR_set_trap_table(info)) | |
668 | BUG(); | |
669 | } | |
670 | ||
671 | preempt_enable(); | |
672 | } | |
673 | ||
674 | static void xen_convert_trap_info(const struct desc_ptr *desc, | |
675 | struct trap_info *traps) | |
676 | { | |
677 | unsigned in, out, count; | |
678 | ||
679 | count = (desc->size+1) / sizeof(gate_desc); | |
680 | BUG_ON(count > 256); | |
681 | ||
682 | for (in = out = 0; in < count; in++) { | |
683 | gate_desc *entry = (gate_desc *)(desc->address) + in; | |
684 | ||
685 | if (cvt_gate_to_trap(in, entry, &traps[out])) | |
686 | out++; | |
687 | } | |
688 | traps[out].address = 0; | |
689 | } | |
690 | ||
691 | void xen_copy_trap_info(struct trap_info *traps) | |
692 | { | |
693 | const struct desc_ptr *desc = this_cpu_ptr(&idt_desc); | |
694 | ||
695 | xen_convert_trap_info(desc, traps); | |
696 | } | |
697 | ||
698 | /* Load a new IDT into Xen. In principle this can be per-CPU, so we | |
699 | hold a spinlock to protect the static traps[] array (static because | |
700 | it avoids allocation, and saves stack space). */ | |
701 | static void xen_load_idt(const struct desc_ptr *desc) | |
702 | { | |
703 | static DEFINE_SPINLOCK(lock); | |
704 | static struct trap_info traps[257]; | |
705 | ||
706 | trace_xen_cpu_load_idt(desc); | |
707 | ||
708 | spin_lock(&lock); | |
709 | ||
710 | memcpy(this_cpu_ptr(&idt_desc), desc, sizeof(idt_desc)); | |
711 | ||
712 | xen_convert_trap_info(desc, traps); | |
713 | ||
714 | xen_mc_flush(); | |
715 | if (HYPERVISOR_set_trap_table(traps)) | |
716 | BUG(); | |
717 | ||
718 | spin_unlock(&lock); | |
719 | } | |
720 | ||
721 | /* Write a GDT descriptor entry. Ignore LDT descriptors, since | |
722 | they're handled differently. */ | |
723 | static void xen_write_gdt_entry(struct desc_struct *dt, int entry, | |
724 | const void *desc, int type) | |
725 | { | |
726 | trace_xen_cpu_write_gdt_entry(dt, entry, desc, type); | |
727 | ||
728 | preempt_disable(); | |
729 | ||
730 | switch (type) { | |
731 | case DESC_LDT: | |
732 | case DESC_TSS: | |
733 | /* ignore */ | |
734 | break; | |
735 | ||
736 | default: { | |
737 | xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]); | |
738 | ||
739 | xen_mc_flush(); | |
740 | if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc)) | |
741 | BUG(); | |
742 | } | |
743 | ||
744 | } | |
745 | ||
746 | preempt_enable(); | |
747 | } | |
748 | ||
749 | /* | |
750 | * Version of write_gdt_entry for use at early boot-time needed to | |
751 | * update an entry as simply as possible. | |
752 | */ | |
753 | static void __init xen_write_gdt_entry_boot(struct desc_struct *dt, int entry, | |
754 | const void *desc, int type) | |
755 | { | |
756 | trace_xen_cpu_write_gdt_entry(dt, entry, desc, type); | |
757 | ||
758 | switch (type) { | |
759 | case DESC_LDT: | |
760 | case DESC_TSS: | |
761 | /* ignore */ | |
762 | break; | |
763 | ||
764 | default: { | |
765 | xmaddr_t maddr = virt_to_machine(&dt[entry]); | |
766 | ||
767 | if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc)) | |
768 | dt[entry] = *(struct desc_struct *)desc; | |
769 | } | |
770 | ||
771 | } | |
772 | } | |
773 | ||
774 | static void xen_load_sp0(struct tss_struct *tss, | |
775 | struct thread_struct *thread) | |
776 | { | |
777 | struct multicall_space mcs; | |
778 | ||
779 | mcs = xen_mc_entry(0); | |
780 | MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0); | |
781 | xen_mc_issue(PARAVIRT_LAZY_CPU); | |
782 | tss->x86_tss.sp0 = thread->sp0; | |
783 | } | |
784 | ||
785 | void xen_set_iopl_mask(unsigned mask) | |
786 | { | |
787 | struct physdev_set_iopl set_iopl; | |
788 | ||
789 | /* Force the change at ring 0. */ | |
790 | set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3; | |
791 | HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl); | |
792 | } | |
793 | ||
794 | static void xen_io_delay(void) | |
795 | { | |
796 | } | |
797 | ||
798 | static DEFINE_PER_CPU(unsigned long, xen_cr0_value); | |
799 | ||
800 | static unsigned long xen_read_cr0(void) | |
801 | { | |
802 | unsigned long cr0 = this_cpu_read(xen_cr0_value); | |
803 | ||
804 | if (unlikely(cr0 == 0)) { | |
805 | cr0 = native_read_cr0(); | |
806 | this_cpu_write(xen_cr0_value, cr0); | |
807 | } | |
808 | ||
809 | return cr0; | |
810 | } | |
811 | ||
812 | static void xen_write_cr0(unsigned long cr0) | |
813 | { | |
814 | struct multicall_space mcs; | |
815 | ||
816 | this_cpu_write(xen_cr0_value, cr0); | |
817 | ||
818 | /* Only pay attention to cr0.TS; everything else is | |
819 | ignored. */ | |
820 | mcs = xen_mc_entry(0); | |
821 | ||
822 | MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0); | |
823 | ||
824 | xen_mc_issue(PARAVIRT_LAZY_CPU); | |
825 | } | |
826 | ||
827 | static void xen_write_cr4(unsigned long cr4) | |
828 | { | |
829 | cr4 &= ~(X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PCE); | |
830 | ||
831 | native_write_cr4(cr4); | |
832 | } | |
833 | #ifdef CONFIG_X86_64 | |
834 | static inline unsigned long xen_read_cr8(void) | |
835 | { | |
836 | return 0; | |
837 | } | |
838 | static inline void xen_write_cr8(unsigned long val) | |
839 | { | |
840 | BUG_ON(val); | |
841 | } | |
842 | #endif | |
843 | ||
844 | static u64 xen_read_msr_safe(unsigned int msr, int *err) | |
845 | { | |
846 | u64 val; | |
847 | ||
848 | if (pmu_msr_read(msr, &val, err)) | |
849 | return val; | |
850 | ||
851 | val = native_read_msr_safe(msr, err); | |
852 | switch (msr) { | |
853 | case MSR_IA32_APICBASE: | |
854 | #ifdef CONFIG_X86_X2APIC | |
855 | if (!(cpuid_ecx(1) & (1 << (X86_FEATURE_X2APIC & 31)))) | |
856 | #endif | |
857 | val &= ~X2APIC_ENABLE; | |
858 | break; | |
859 | } | |
860 | return val; | |
861 | } | |
862 | ||
863 | static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high) | |
864 | { | |
865 | int ret; | |
866 | ||
867 | ret = 0; | |
868 | ||
869 | switch (msr) { | |
870 | #ifdef CONFIG_X86_64 | |
871 | unsigned which; | |
872 | u64 base; | |
873 | ||
874 | case MSR_FS_BASE: which = SEGBASE_FS; goto set; | |
875 | case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set; | |
876 | case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set; | |
877 | ||
878 | set: | |
879 | base = ((u64)high << 32) | low; | |
880 | if (HYPERVISOR_set_segment_base(which, base) != 0) | |
881 | ret = -EIO; | |
882 | break; | |
883 | #endif | |
884 | ||
885 | case MSR_STAR: | |
886 | case MSR_CSTAR: | |
887 | case MSR_LSTAR: | |
888 | case MSR_SYSCALL_MASK: | |
889 | case MSR_IA32_SYSENTER_CS: | |
890 | case MSR_IA32_SYSENTER_ESP: | |
891 | case MSR_IA32_SYSENTER_EIP: | |
892 | /* Fast syscall setup is all done in hypercalls, so | |
893 | these are all ignored. Stub them out here to stop | |
894 | Xen console noise. */ | |
895 | break; | |
896 | ||
897 | default: | |
898 | if (!pmu_msr_write(msr, low, high, &ret)) | |
899 | ret = native_write_msr_safe(msr, low, high); | |
900 | } | |
901 | ||
902 | return ret; | |
903 | } | |
904 | ||
905 | static u64 xen_read_msr(unsigned int msr) | |
906 | { | |
907 | /* | |
908 | * This will silently swallow a #GP from RDMSR. It may be worth | |
909 | * changing that. | |
910 | */ | |
911 | int err; | |
912 | ||
913 | return xen_read_msr_safe(msr, &err); | |
914 | } | |
915 | ||
916 | static void xen_write_msr(unsigned int msr, unsigned low, unsigned high) | |
917 | { | |
918 | /* | |
919 | * This will silently swallow a #GP from WRMSR. It may be worth | |
920 | * changing that. | |
921 | */ | |
922 | xen_write_msr_safe(msr, low, high); | |
923 | } | |
924 | ||
925 | void xen_setup_shared_info(void) | |
926 | { | |
989513a7 | 927 | set_fixmap(FIX_PARAVIRT_BOOTMAP, xen_start_info->shared_info); |
e1dab14c | 928 | |
989513a7 JG |
929 | HYPERVISOR_shared_info = |
930 | (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP); | |
e1dab14c | 931 | |
e1dab14c | 932 | xen_setup_mfn_list_list(); |
d162809f | 933 | |
0e4d5837 AA |
934 | if (system_state == SYSTEM_BOOTING) { |
935 | #ifndef CONFIG_SMP | |
936 | /* | |
937 | * In UP this is as good a place as any to set up shared info. | |
938 | * Limit this to boot only, at restore vcpu setup is done via | |
939 | * xen_vcpu_restore(). | |
940 | */ | |
941 | xen_setup_vcpu_info_placement(); | |
942 | #endif | |
943 | /* | |
944 | * Now that shared info is set up we can start using routines | |
945 | * that point to pvclock area. | |
946 | */ | |
d162809f | 947 | xen_init_time_ops(); |
0e4d5837 | 948 | } |
e1dab14c VK |
949 | } |
950 | ||
951 | /* This is called once we have the cpu_possible_mask */ | |
0e4d5837 | 952 | void __ref xen_setup_vcpu_info_placement(void) |
e1dab14c VK |
953 | { |
954 | int cpu; | |
955 | ||
956 | for_each_possible_cpu(cpu) { | |
957 | /* Set up direct vCPU id mapping for PV guests. */ | |
958 | per_cpu(xen_vcpu_id, cpu) = cpu; | |
c9b5d98b AA |
959 | |
960 | /* | |
961 | * xen_vcpu_setup(cpu) can fail -- in which case it | |
962 | * falls back to the shared_info version for cpus | |
963 | * where xen_vcpu_nr(cpu) < MAX_VIRT_CPUS. | |
964 | * | |
965 | * xen_cpu_up_prepare_pv() handles the rest by failing | |
966 | * them in hotplug. | |
967 | */ | |
968 | (void) xen_vcpu_setup(cpu); | |
e1dab14c VK |
969 | } |
970 | ||
971 | /* | |
972 | * xen_vcpu_setup managed to place the vcpu_info within the | |
973 | * percpu area for all cpus, so make use of it. | |
974 | */ | |
975 | if (xen_have_vcpu_info_placement) { | |
976 | pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct); | |
977 | pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct); | |
978 | pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct); | |
979 | pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct); | |
980 | pv_mmu_ops.read_cr2 = xen_read_cr2_direct; | |
981 | } | |
982 | } | |
983 | ||
984 | static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf, | |
985 | unsigned long addr, unsigned len) | |
986 | { | |
987 | char *start, *end, *reloc; | |
988 | unsigned ret; | |
989 | ||
990 | start = end = reloc = NULL; | |
991 | ||
992 | #define SITE(op, x) \ | |
993 | case PARAVIRT_PATCH(op.x): \ | |
994 | if (xen_have_vcpu_info_placement) { \ | |
995 | start = (char *)xen_##x##_direct; \ | |
996 | end = xen_##x##_direct_end; \ | |
997 | reloc = xen_##x##_direct_reloc; \ | |
998 | } \ | |
999 | goto patch_site | |
1000 | ||
1001 | switch (type) { | |
1002 | SITE(pv_irq_ops, irq_enable); | |
1003 | SITE(pv_irq_ops, irq_disable); | |
1004 | SITE(pv_irq_ops, save_fl); | |
1005 | SITE(pv_irq_ops, restore_fl); | |
1006 | #undef SITE | |
1007 | ||
1008 | patch_site: | |
1009 | if (start == NULL || (end-start) > len) | |
1010 | goto default_patch; | |
1011 | ||
1012 | ret = paravirt_patch_insns(insnbuf, len, start, end); | |
1013 | ||
1014 | /* Note: because reloc is assigned from something that | |
1015 | appears to be an array, gcc assumes it's non-null, | |
1016 | but doesn't know its relationship with start and | |
1017 | end. */ | |
1018 | if (reloc > start && reloc < end) { | |
1019 | int reloc_off = reloc - start; | |
1020 | long *relocp = (long *)(insnbuf + reloc_off); | |
1021 | long delta = start - (char *)addr; | |
1022 | ||
1023 | *relocp += delta; | |
1024 | } | |
1025 | break; | |
1026 | ||
1027 | default_patch: | |
1028 | default: | |
1029 | ret = paravirt_patch_default(type, clobbers, insnbuf, | |
1030 | addr, len); | |
1031 | break; | |
1032 | } | |
1033 | ||
1034 | return ret; | |
1035 | } | |
1036 | ||
1037 | static const struct pv_info xen_info __initconst = { | |
1038 | .shared_kernel_pmd = 0, | |
1039 | ||
1040 | #ifdef CONFIG_X86_64 | |
1041 | .extra_user_64bit_cs = FLAT_USER_CS64, | |
1042 | #endif | |
1043 | .name = "Xen", | |
1044 | }; | |
1045 | ||
1046 | static const struct pv_init_ops xen_init_ops __initconst = { | |
1047 | .patch = xen_patch, | |
1048 | }; | |
1049 | ||
1050 | static const struct pv_cpu_ops xen_cpu_ops __initconst = { | |
1051 | .cpuid = xen_cpuid, | |
1052 | ||
1053 | .set_debugreg = xen_set_debugreg, | |
1054 | .get_debugreg = xen_get_debugreg, | |
1055 | ||
1056 | .read_cr0 = xen_read_cr0, | |
1057 | .write_cr0 = xen_write_cr0, | |
1058 | ||
1059 | .read_cr4 = native_read_cr4, | |
1060 | .write_cr4 = xen_write_cr4, | |
1061 | ||
1062 | #ifdef CONFIG_X86_64 | |
1063 | .read_cr8 = xen_read_cr8, | |
1064 | .write_cr8 = xen_write_cr8, | |
1065 | #endif | |
1066 | ||
1067 | .wbinvd = native_wbinvd, | |
1068 | ||
1069 | .read_msr = xen_read_msr, | |
1070 | .write_msr = xen_write_msr, | |
1071 | ||
1072 | .read_msr_safe = xen_read_msr_safe, | |
1073 | .write_msr_safe = xen_write_msr_safe, | |
1074 | ||
1075 | .read_pmc = xen_read_pmc, | |
1076 | ||
1077 | .iret = xen_iret, | |
1078 | #ifdef CONFIG_X86_64 | |
1079 | .usergs_sysret64 = xen_sysret64, | |
1080 | #endif | |
1081 | ||
1082 | .load_tr_desc = paravirt_nop, | |
1083 | .set_ldt = xen_set_ldt, | |
1084 | .load_gdt = xen_load_gdt, | |
1085 | .load_idt = xen_load_idt, | |
1086 | .load_tls = xen_load_tls, | |
1087 | #ifdef CONFIG_X86_64 | |
1088 | .load_gs_index = xen_load_gs_index, | |
1089 | #endif | |
1090 | ||
1091 | .alloc_ldt = xen_alloc_ldt, | |
1092 | .free_ldt = xen_free_ldt, | |
1093 | ||
1094 | .store_idt = native_store_idt, | |
1095 | .store_tr = xen_store_tr, | |
1096 | ||
1097 | .write_ldt_entry = xen_write_ldt_entry, | |
1098 | .write_gdt_entry = xen_write_gdt_entry, | |
1099 | .write_idt_entry = xen_write_idt_entry, | |
1100 | .load_sp0 = xen_load_sp0, | |
1101 | ||
1102 | .set_iopl_mask = xen_set_iopl_mask, | |
1103 | .io_delay = xen_io_delay, | |
1104 | ||
1105 | /* Xen takes care of %gs when switching to usermode for us */ | |
1106 | .swapgs = paravirt_nop, | |
1107 | ||
1108 | .start_context_switch = paravirt_start_context_switch, | |
1109 | .end_context_switch = xen_end_context_switch, | |
1110 | }; | |
1111 | ||
1112 | static void xen_restart(char *msg) | |
1113 | { | |
1114 | xen_reboot(SHUTDOWN_reboot); | |
1115 | } | |
1116 | ||
1117 | static void xen_machine_halt(void) | |
1118 | { | |
1119 | xen_reboot(SHUTDOWN_poweroff); | |
1120 | } | |
1121 | ||
1122 | static void xen_machine_power_off(void) | |
1123 | { | |
1124 | if (pm_power_off) | |
1125 | pm_power_off(); | |
1126 | xen_reboot(SHUTDOWN_poweroff); | |
1127 | } | |
1128 | ||
1129 | static void xen_crash_shutdown(struct pt_regs *regs) | |
1130 | { | |
1131 | xen_reboot(SHUTDOWN_crash); | |
1132 | } | |
1133 | ||
1134 | static const struct machine_ops xen_machine_ops __initconst = { | |
1135 | .restart = xen_restart, | |
1136 | .halt = xen_machine_halt, | |
1137 | .power_off = xen_machine_power_off, | |
1138 | .shutdown = xen_machine_halt, | |
1139 | .crash_shutdown = xen_crash_shutdown, | |
1140 | .emergency_restart = xen_emergency_restart, | |
1141 | }; | |
1142 | ||
1143 | static unsigned char xen_get_nmi_reason(void) | |
1144 | { | |
1145 | unsigned char reason = 0; | |
1146 | ||
1147 | /* Construct a value which looks like it came from port 0x61. */ | |
1148 | if (test_bit(_XEN_NMIREASON_io_error, | |
1149 | &HYPERVISOR_shared_info->arch.nmi_reason)) | |
1150 | reason |= NMI_REASON_IOCHK; | |
1151 | if (test_bit(_XEN_NMIREASON_pci_serr, | |
1152 | &HYPERVISOR_shared_info->arch.nmi_reason)) | |
1153 | reason |= NMI_REASON_SERR; | |
1154 | ||
1155 | return reason; | |
1156 | } | |
1157 | ||
1158 | static void __init xen_boot_params_init_edd(void) | |
1159 | { | |
1160 | #if IS_ENABLED(CONFIG_EDD) | |
1161 | struct xen_platform_op op; | |
1162 | struct edd_info *edd_info; | |
1163 | u32 *mbr_signature; | |
1164 | unsigned nr; | |
1165 | int ret; | |
1166 | ||
1167 | edd_info = boot_params.eddbuf; | |
1168 | mbr_signature = boot_params.edd_mbr_sig_buffer; | |
1169 | ||
1170 | op.cmd = XENPF_firmware_info; | |
1171 | ||
1172 | op.u.firmware_info.type = XEN_FW_DISK_INFO; | |
1173 | for (nr = 0; nr < EDDMAXNR; nr++) { | |
1174 | struct edd_info *info = edd_info + nr; | |
1175 | ||
1176 | op.u.firmware_info.index = nr; | |
1177 | info->params.length = sizeof(info->params); | |
1178 | set_xen_guest_handle(op.u.firmware_info.u.disk_info.edd_params, | |
1179 | &info->params); | |
1180 | ret = HYPERVISOR_platform_op(&op); | |
1181 | if (ret) | |
1182 | break; | |
1183 | ||
1184 | #define C(x) info->x = op.u.firmware_info.u.disk_info.x | |
1185 | C(device); | |
1186 | C(version); | |
1187 | C(interface_support); | |
1188 | C(legacy_max_cylinder); | |
1189 | C(legacy_max_head); | |
1190 | C(legacy_sectors_per_track); | |
1191 | #undef C | |
1192 | } | |
1193 | boot_params.eddbuf_entries = nr; | |
1194 | ||
1195 | op.u.firmware_info.type = XEN_FW_DISK_MBR_SIGNATURE; | |
1196 | for (nr = 0; nr < EDD_MBR_SIG_MAX; nr++) { | |
1197 | op.u.firmware_info.index = nr; | |
1198 | ret = HYPERVISOR_platform_op(&op); | |
1199 | if (ret) | |
1200 | break; | |
1201 | mbr_signature[nr] = op.u.firmware_info.u.disk_mbr_signature.mbr_signature; | |
1202 | } | |
1203 | boot_params.edd_mbr_sig_buf_entries = nr; | |
1204 | #endif | |
1205 | } | |
1206 | ||
1207 | /* | |
1208 | * Set up the GDT and segment registers for -fstack-protector. Until | |
1209 | * we do this, we have to be careful not to call any stack-protected | |
1210 | * function, which is most of the kernel. | |
1211 | */ | |
1212 | static void xen_setup_gdt(int cpu) | |
1213 | { | |
1214 | pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry_boot; | |
1215 | pv_cpu_ops.load_gdt = xen_load_gdt_boot; | |
1216 | ||
1217 | setup_stack_canary_segment(0); | |
1218 | switch_to_new_gdt(0); | |
1219 | ||
1220 | pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry; | |
1221 | pv_cpu_ops.load_gdt = xen_load_gdt; | |
1222 | } | |
1223 | ||
1224 | static void __init xen_dom0_set_legacy_features(void) | |
1225 | { | |
1226 | x86_platform.legacy.rtc = 1; | |
1227 | } | |
1228 | ||
1229 | /* First C function to be called on Xen boot */ | |
1230 | asmlinkage __visible void __init xen_start_kernel(void) | |
1231 | { | |
1232 | struct physdev_set_iopl set_iopl; | |
1233 | unsigned long initrd_start = 0; | |
1234 | int rc; | |
1235 | ||
1236 | if (!xen_start_info) | |
1237 | return; | |
1238 | ||
1239 | xen_domain_type = XEN_PV_DOMAIN; | |
1240 | ||
1241 | xen_setup_features(); | |
1242 | ||
1243 | xen_setup_machphys_mapping(); | |
1244 | ||
1245 | /* Install Xen paravirt ops */ | |
1246 | pv_info = xen_info; | |
1247 | pv_init_ops = xen_init_ops; | |
1248 | pv_cpu_ops = xen_cpu_ops; | |
1249 | ||
1250 | x86_platform.get_nmi_reason = xen_get_nmi_reason; | |
1251 | ||
1252 | x86_init.resources.memory_setup = xen_memory_setup; | |
1253 | x86_init.oem.arch_setup = xen_arch_setup; | |
1254 | x86_init.oem.banner = xen_banner; | |
1255 | ||
e1dab14c VK |
1256 | /* |
1257 | * Set up some pagetable state before starting to set any ptes. | |
1258 | */ | |
1259 | ||
1260 | xen_init_mmu_ops(); | |
1261 | ||
1262 | /* Prevent unwanted bits from being set in PTEs. */ | |
1263 | __supported_pte_mask &= ~_PAGE_GLOBAL; | |
1264 | ||
1265 | /* | |
1266 | * Prevent page tables from being allocated in highmem, even | |
1267 | * if CONFIG_HIGHPTE is enabled. | |
1268 | */ | |
1269 | __userpte_alloc_gfp &= ~__GFP_HIGHMEM; | |
1270 | ||
1271 | /* Work out if we support NX */ | |
1272 | x86_configure_nx(); | |
1273 | ||
1274 | /* Get mfn list */ | |
1275 | xen_build_dynamic_phys_to_machine(); | |
1276 | ||
1277 | /* | |
1278 | * Set up kernel GDT and segment registers, mainly so that | |
1279 | * -fstack-protector code can be executed. | |
1280 | */ | |
1281 | xen_setup_gdt(0); | |
1282 | ||
1283 | xen_init_irq_ops(); | |
0808e80c | 1284 | xen_init_capabilities(); |
e1dab14c VK |
1285 | |
1286 | #ifdef CONFIG_X86_LOCAL_APIC | |
1287 | /* | |
1288 | * set up the basic apic ops. | |
1289 | */ | |
1290 | xen_init_apic(); | |
1291 | #endif | |
1292 | ||
1293 | if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) { | |
1294 | pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start; | |
1295 | pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit; | |
1296 | } | |
1297 | ||
1298 | machine_ops = xen_machine_ops; | |
1299 | ||
1300 | /* | |
1301 | * The only reliable way to retain the initial address of the | |
1302 | * percpu gdt_page is to remember it here, so we can go and | |
1303 | * mark it RW later, when the initial percpu area is freed. | |
1304 | */ | |
1305 | xen_initial_gdt = &per_cpu(gdt_page, 0); | |
1306 | ||
1307 | xen_smp_init(); | |
1308 | ||
1309 | #ifdef CONFIG_ACPI_NUMA | |
1310 | /* | |
1311 | * The pages we from Xen are not related to machine pages, so | |
1312 | * any NUMA information the kernel tries to get from ACPI will | |
1313 | * be meaningless. Prevent it from trying. | |
1314 | */ | |
1315 | acpi_numa = -1; | |
1316 | #endif | |
ad73fd59 AA |
1317 | /* Let's presume PV guests always boot on vCPU with id 0. */ |
1318 | per_cpu(xen_vcpu_id, 0) = 0; | |
1319 | ||
1320 | /* | |
1321 | * Setup xen_vcpu early because start_kernel needs it for | |
1322 | * local_irq_disable(), irqs_disabled(). | |
1323 | * | |
1324 | * Don't do the full vcpu_info placement stuff until we have | |
1325 | * the cpu_possible_mask and a non-dummy shared_info. | |
1326 | */ | |
1327 | xen_vcpu_info_reset(0); | |
e1dab14c VK |
1328 | |
1329 | WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_pv, xen_cpu_dead_pv)); | |
1330 | ||
1331 | local_irq_disable(); | |
1332 | early_boot_irqs_disabled = true; | |
1333 | ||
1334 | xen_raw_console_write("mapping kernel into physical memory\n"); | |
1335 | xen_setup_kernel_pagetable((pgd_t *)xen_start_info->pt_base, | |
1336 | xen_start_info->nr_pages); | |
1337 | xen_reserve_special_pages(); | |
1338 | ||
1339 | /* keep using Xen gdt for now; no urgent need to change it */ | |
1340 | ||
1341 | #ifdef CONFIG_X86_32 | |
1342 | pv_info.kernel_rpl = 1; | |
1343 | if (xen_feature(XENFEAT_supervisor_mode_kernel)) | |
1344 | pv_info.kernel_rpl = 0; | |
1345 | #else | |
1346 | pv_info.kernel_rpl = 0; | |
1347 | #endif | |
1348 | /* set the limit of our address space */ | |
1349 | xen_reserve_top(); | |
1350 | ||
1351 | /* | |
1352 | * We used to do this in xen_arch_setup, but that is too late | |
1353 | * on AMD were early_cpu_init (run before ->arch_setup()) calls | |
1354 | * early_amd_init which pokes 0xcf8 port. | |
1355 | */ | |
1356 | set_iopl.iopl = 1; | |
1357 | rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl); | |
1358 | if (rc != 0) | |
1359 | xen_raw_printk("physdev_op failed %d\n", rc); | |
1360 | ||
1361 | #ifdef CONFIG_X86_32 | |
1362 | /* set up basic CPUID stuff */ | |
1363 | cpu_detect(&new_cpu_data); | |
1364 | set_cpu_cap(&new_cpu_data, X86_FEATURE_FPU); | |
1365 | new_cpu_data.x86_capability[CPUID_1_EDX] = cpuid_edx(1); | |
1366 | #endif | |
1367 | ||
1368 | if (xen_start_info->mod_start) { | |
1369 | if (xen_start_info->flags & SIF_MOD_START_PFN) | |
1370 | initrd_start = PFN_PHYS(xen_start_info->mod_start); | |
1371 | else | |
1372 | initrd_start = __pa(xen_start_info->mod_start); | |
1373 | } | |
1374 | ||
1375 | /* Poke various useful things into boot_params */ | |
1376 | boot_params.hdr.type_of_loader = (9 << 4) | 0; | |
1377 | boot_params.hdr.ramdisk_image = initrd_start; | |
1378 | boot_params.hdr.ramdisk_size = xen_start_info->mod_len; | |
1379 | boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line); | |
1380 | boot_params.hdr.hardware_subarch = X86_SUBARCH_XEN; | |
1381 | ||
1382 | if (!xen_initial_domain()) { | |
1383 | add_preferred_console("xenboot", 0, NULL); | |
1384 | add_preferred_console("tty", 0, NULL); | |
1385 | add_preferred_console("hvc", 0, NULL); | |
1386 | if (pci_xen) | |
1387 | x86_init.pci.arch_init = pci_xen_init; | |
1388 | } else { | |
1389 | const struct dom0_vga_console_info *info = | |
1390 | (void *)((char *)xen_start_info + | |
1391 | xen_start_info->console.dom0.info_off); | |
1392 | struct xen_platform_op op = { | |
1393 | .cmd = XENPF_firmware_info, | |
1394 | .interface_version = XENPF_INTERFACE_VERSION, | |
1395 | .u.firmware_info.type = XEN_FW_KBD_SHIFT_FLAGS, | |
1396 | }; | |
1397 | ||
1398 | x86_platform.set_legacy_features = | |
1399 | xen_dom0_set_legacy_features; | |
1400 | xen_init_vga(info, xen_start_info->console.dom0.info_size); | |
1401 | xen_start_info->console.domU.mfn = 0; | |
1402 | xen_start_info->console.domU.evtchn = 0; | |
1403 | ||
1404 | if (HYPERVISOR_platform_op(&op) == 0) | |
1405 | boot_params.kbd_status = op.u.firmware_info.u.kbd_shift_flags; | |
1406 | ||
1407 | /* Make sure ACS will be enabled */ | |
1408 | pci_request_acs(); | |
1409 | ||
1410 | xen_acpi_sleep_register(); | |
1411 | ||
1412 | /* Avoid searching for BIOS MP tables */ | |
1413 | x86_init.mpparse.find_smp_config = x86_init_noop; | |
1414 | x86_init.mpparse.get_smp_config = x86_init_uint_noop; | |
1415 | ||
1416 | xen_boot_params_init_edd(); | |
1417 | } | |
1418 | #ifdef CONFIG_PCI | |
1419 | /* PCI BIOS service won't work from a PV guest. */ | |
1420 | pci_probe &= ~PCI_PROBE_BIOS; | |
1421 | #endif | |
1422 | xen_raw_console_write("about to get started...\n"); | |
1423 | ||
ad73fd59 | 1424 | /* We need this for printk timestamps */ |
e1dab14c VK |
1425 | xen_setup_runstate_info(0); |
1426 | ||
1427 | xen_efi_init(); | |
1428 | ||
1429 | /* Start the world */ | |
1430 | #ifdef CONFIG_X86_32 | |
1431 | i386_start_kernel(); | |
1432 | #else | |
1433 | cr4_init_shadow(); /* 32b kernel does this in i386_start_kernel() */ | |
1434 | x86_64_start_reservations((char *)__pa_symbol(&boot_params)); | |
1435 | #endif | |
1436 | } | |
1437 | ||
1438 | static int xen_cpu_up_prepare_pv(unsigned int cpu) | |
1439 | { | |
1440 | int rc; | |
1441 | ||
c9b5d98b AA |
1442 | if (per_cpu(xen_vcpu, cpu) == NULL) |
1443 | return -ENODEV; | |
1444 | ||
e1dab14c VK |
1445 | xen_setup_timer(cpu); |
1446 | ||
1447 | rc = xen_smp_intr_init(cpu); | |
1448 | if (rc) { | |
1449 | WARN(1, "xen_smp_intr_init() for CPU %d failed: %d\n", | |
1450 | cpu, rc); | |
1451 | return rc; | |
1452 | } | |
04e95761 VK |
1453 | |
1454 | rc = xen_smp_intr_init_pv(cpu); | |
1455 | if (rc) { | |
1456 | WARN(1, "xen_smp_intr_init_pv() for CPU %d failed: %d\n", | |
1457 | cpu, rc); | |
1458 | return rc; | |
1459 | } | |
1460 | ||
e1dab14c VK |
1461 | return 0; |
1462 | } | |
1463 | ||
1464 | static int xen_cpu_dead_pv(unsigned int cpu) | |
1465 | { | |
1466 | xen_smp_intr_free(cpu); | |
04e95761 | 1467 | xen_smp_intr_free_pv(cpu); |
e1dab14c VK |
1468 | |
1469 | xen_teardown_timer(cpu); | |
1470 | ||
1471 | return 0; | |
1472 | } | |
1473 | ||
1474 | static uint32_t __init xen_platform_pv(void) | |
1475 | { | |
1476 | if (xen_pv_domain()) | |
1477 | return xen_cpuid_base(); | |
1478 | ||
1479 | return 0; | |
1480 | } | |
1481 | ||
e1dab14c VK |
1482 | const struct hypervisor_x86 x86_hyper_xen_pv = { |
1483 | .name = "Xen PV", | |
1484 | .detect = xen_platform_pv, | |
e1dab14c VK |
1485 | .pin_vcpu = xen_pin_vcpu, |
1486 | }; | |
1487 | EXPORT_SYMBOL(x86_hyper_xen_pv); |