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21#include <linux/errno.h>
22#include <linux/module.h>
23#include <linux/efi.h>
24#include <linux/bcd.h>
25#include <linux/highmem.h>
26#include <linux/kprobes.h>
27
28#include <asm/bug.h>
29#include <asm/paravirt.h>
30#include <asm/debugreg.h>
31#include <asm/desc.h>
32#include <asm/setup.h>
33#include <asm/pgtable.h>
34#include <asm/time.h>
35#include <asm/pgalloc.h>
36#include <asm/irq.h>
37#include <asm/delay.h>
38#include <asm/fixmap.h>
39#include <asm/apic.h>
40#include <asm/tlbflush.h>
41#include <asm/timer.h>
42#include <asm/special_insns.h>
43
44
45void _paravirt_nop(void)
46{
47}
48
49
50u32 _paravirt_ident_32(u32 x)
51{
52 return x;
53}
54
55u64 _paravirt_ident_64(u64 x)
56{
57 return x;
58}
59
60void __init default_banner(void)
61{
62 printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
63 pv_info.name);
64}
65
66
67static const unsigned char ud2a[] = { 0x0f, 0x0b };
68
69unsigned paravirt_patch_nop(void)
70{
71 return 0;
72}
73
74unsigned paravirt_patch_ignore(unsigned len)
75{
76 return len;
77}
78
79struct branch {
80 unsigned char opcode;
81 u32 delta;
82} __attribute__((packed));
83
84unsigned paravirt_patch_call(void *insnbuf,
85 const void *target, u16 tgt_clobbers,
86 unsigned long addr, u16 site_clobbers,
87 unsigned len)
88{
89 struct branch *b = insnbuf;
90 unsigned long delta = (unsigned long)target - (addr+5);
91
92 if (tgt_clobbers & ~site_clobbers)
93 return len;
94 if (len < 5)
95 return len;
96
97 b->opcode = 0xe8;
98 b->delta = delta;
99 BUILD_BUG_ON(sizeof(*b) != 5);
100
101 return 5;
102}
103
104unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
105 unsigned long addr, unsigned len)
106{
107 struct branch *b = insnbuf;
108 unsigned long delta = (unsigned long)target - (addr+5);
109
110 if (len < 5)
111 return len;
112
113 b->opcode = 0xe9;
114 b->delta = delta;
115
116 return 5;
117}
118
119
120
121static void *get_call_destination(u8 type)
122{
123 struct paravirt_patch_template tmpl = {
124 .pv_init_ops = pv_init_ops,
125 .pv_time_ops = pv_time_ops,
126 .pv_cpu_ops = pv_cpu_ops,
127 .pv_irq_ops = pv_irq_ops,
128 .pv_apic_ops = pv_apic_ops,
129 .pv_mmu_ops = pv_mmu_ops,
130#ifdef CONFIG_PARAVIRT_SPINLOCKS
131 .pv_lock_ops = pv_lock_ops,
132#endif
133 };
134 return *((void **)&tmpl + type);
135}
136
137unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
138 unsigned long addr, unsigned len)
139{
140 void *opfunc = get_call_destination(type);
141 unsigned ret;
142
143 if (opfunc == NULL)
144
145 ret = paravirt_patch_insns(insnbuf, len, ud2a, ud2a+sizeof(ud2a));
146 else if (opfunc == _paravirt_nop)
147
148 ret = paravirt_patch_nop();
149
150
151 else if (opfunc == _paravirt_ident_32)
152 ret = paravirt_patch_ident_32(insnbuf, len);
153 else if (opfunc == _paravirt_ident_64)
154 ret = paravirt_patch_ident_64(insnbuf, len);
155
156 else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
157#ifdef CONFIG_X86_32
158 type == PARAVIRT_PATCH(pv_cpu_ops.irq_enable_sysexit) ||
159#endif
160 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret32) ||
161 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret64))
162
163 ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
164 else
165
166
167 ret = paravirt_patch_call(insnbuf, opfunc, CLBR_ANY,
168 addr, clobbers, len);
169
170 return ret;
171}
172
173unsigned paravirt_patch_insns(void *insnbuf, unsigned len,
174 const char *start, const char *end)
175{
176 unsigned insn_len = end - start;
177
178 if (insn_len > len || start == NULL)
179 insn_len = len;
180 else
181 memcpy(insnbuf, start, insn_len);
182
183 return insn_len;
184}
185
186static void native_flush_tlb(void)
187{
188 __native_flush_tlb();
189}
190
191
192
193
194
195static void native_flush_tlb_global(void)
196{
197 __native_flush_tlb_global();
198}
199
200static void native_flush_tlb_single(unsigned long addr)
201{
202 __native_flush_tlb_single(addr);
203}
204
205struct static_key paravirt_steal_enabled;
206struct static_key paravirt_steal_rq_enabled;
207
208static u64 native_steal_clock(int cpu)
209{
210 return 0;
211}
212
213
214extern void native_iret(void);
215extern void native_irq_enable_sysexit(void);
216extern void native_usergs_sysret32(void);
217extern void native_usergs_sysret64(void);
218
219static struct resource reserve_ioports = {
220 .start = 0,
221 .end = IO_SPACE_LIMIT,
222 .name = "paravirt-ioport",
223 .flags = IORESOURCE_IO | IORESOURCE_BUSY,
224};
225
226
227
228
229
230
231
232
233int paravirt_disable_iospace(void)
234{
235 return request_resource(&ioport_resource, &reserve_ioports);
236}
237
238static DEFINE_PER_CPU(enum paravirt_lazy_mode, paravirt_lazy_mode) = PARAVIRT_LAZY_NONE;
239
240static inline void enter_lazy(enum paravirt_lazy_mode mode)
241{
242 BUG_ON(this_cpu_read(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE);
243
244 this_cpu_write(paravirt_lazy_mode, mode);
245}
246
247static void leave_lazy(enum paravirt_lazy_mode mode)
248{
249 BUG_ON(this_cpu_read(paravirt_lazy_mode) != mode);
250
251 this_cpu_write(paravirt_lazy_mode, PARAVIRT_LAZY_NONE);
252}
253
254void paravirt_enter_lazy_mmu(void)
255{
256 enter_lazy(PARAVIRT_LAZY_MMU);
257}
258
259void paravirt_leave_lazy_mmu(void)
260{
261 leave_lazy(PARAVIRT_LAZY_MMU);
262}
263
264void paravirt_flush_lazy_mmu(void)
265{
266 preempt_disable();
267
268 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
269 arch_leave_lazy_mmu_mode();
270 arch_enter_lazy_mmu_mode();
271 }
272
273 preempt_enable();
274}
275
276void paravirt_start_context_switch(struct task_struct *prev)
277{
278 BUG_ON(preemptible());
279
280 if (this_cpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) {
281 arch_leave_lazy_mmu_mode();
282 set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES);
283 }
284 enter_lazy(PARAVIRT_LAZY_CPU);
285}
286
287void paravirt_end_context_switch(struct task_struct *next)
288{
289 BUG_ON(preemptible());
290
291 leave_lazy(PARAVIRT_LAZY_CPU);
292
293 if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES))
294 arch_enter_lazy_mmu_mode();
295}
296
297enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
298{
299 if (in_interrupt())
300 return PARAVIRT_LAZY_NONE;
301
302 return this_cpu_read(paravirt_lazy_mode);
303}
304
305struct pv_info pv_info = {
306 .name = "bare hardware",
307 .paravirt_enabled = 0,
308 .kernel_rpl = 0,
309 .shared_kernel_pmd = 1,
310
311#ifdef CONFIG_X86_64
312 .extra_user_64bit_cs = __USER_CS,
313#endif
314};
315
316struct pv_init_ops pv_init_ops = {
317 .patch = native_patch,
318};
319
320struct pv_time_ops pv_time_ops = {
321 .sched_clock = native_sched_clock,
322 .steal_clock = native_steal_clock,
323};
324
325__visible struct pv_irq_ops pv_irq_ops = {
326 .save_fl = __PV_IS_CALLEE_SAVE(native_save_fl),
327 .restore_fl = __PV_IS_CALLEE_SAVE(native_restore_fl),
328 .irq_disable = __PV_IS_CALLEE_SAVE(native_irq_disable),
329 .irq_enable = __PV_IS_CALLEE_SAVE(native_irq_enable),
330 .safe_halt = native_safe_halt,
331 .halt = native_halt,
332#ifdef CONFIG_X86_64
333 .adjust_exception_frame = paravirt_nop,
334#endif
335};
336
337__visible struct pv_cpu_ops pv_cpu_ops = {
338 .cpuid = native_cpuid,
339 .get_debugreg = native_get_debugreg,
340 .set_debugreg = native_set_debugreg,
341 .clts = native_clts,
342 .read_cr0 = native_read_cr0,
343 .write_cr0 = native_write_cr0,
344 .read_cr4 = native_read_cr4,
345 .read_cr4_safe = native_read_cr4_safe,
346 .write_cr4 = native_write_cr4,
347#ifdef CONFIG_X86_64
348 .read_cr8 = native_read_cr8,
349 .write_cr8 = native_write_cr8,
350#endif
351 .wbinvd = native_wbinvd,
352 .read_msr = native_read_msr_safe,
353 .write_msr = native_write_msr_safe,
354 .read_tsc = native_read_tsc,
355 .read_pmc = native_read_pmc,
356 .read_tscp = native_read_tscp,
357 .load_tr_desc = native_load_tr_desc,
358 .set_ldt = native_set_ldt,
359 .load_gdt = native_load_gdt,
360 .load_idt = native_load_idt,
361 .store_idt = native_store_idt,
362 .store_tr = native_store_tr,
363 .load_tls = native_load_tls,
364#ifdef CONFIG_X86_64
365 .load_gs_index = native_load_gs_index,
366#endif
367 .write_ldt_entry = native_write_ldt_entry,
368 .write_gdt_entry = native_write_gdt_entry,
369 .write_idt_entry = native_write_idt_entry,
370
371 .alloc_ldt = paravirt_nop,
372 .free_ldt = paravirt_nop,
373
374 .load_sp0 = native_load_sp0,
375
376#if defined(CONFIG_X86_32)
377 .irq_enable_sysexit = native_irq_enable_sysexit,
378#endif
379#ifdef CONFIG_X86_64
380#ifdef CONFIG_IA32_EMULATION
381 .usergs_sysret32 = native_usergs_sysret32,
382#endif
383 .usergs_sysret64 = native_usergs_sysret64,
384#endif
385 .iret = native_iret,
386 .swapgs = native_swapgs,
387
388 .set_iopl_mask = native_set_iopl_mask,
389 .io_delay = native_io_delay,
390
391 .start_context_switch = paravirt_nop,
392 .end_context_switch = paravirt_nop,
393};
394
395
396NOKPROBE_SYMBOL(native_get_debugreg);
397NOKPROBE_SYMBOL(native_set_debugreg);
398NOKPROBE_SYMBOL(native_load_idt);
399
400struct pv_apic_ops pv_apic_ops = {
401#ifdef CONFIG_X86_LOCAL_APIC
402 .startup_ipi_hook = paravirt_nop,
403#endif
404};
405
406#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_PAE)
407
408#define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_32)
409#else
410
411#define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_64)
412#endif
413
414struct pv_mmu_ops pv_mmu_ops = {
415
416 .read_cr2 = native_read_cr2,
417 .write_cr2 = native_write_cr2,
418 .read_cr3 = native_read_cr3,
419 .write_cr3 = native_write_cr3,
420
421 .flush_tlb_user = native_flush_tlb,
422 .flush_tlb_kernel = native_flush_tlb_global,
423 .flush_tlb_single = native_flush_tlb_single,
424 .flush_tlb_others = native_flush_tlb_others,
425
426 .pgd_alloc = __paravirt_pgd_alloc,
427 .pgd_free = paravirt_nop,
428
429 .alloc_pte = paravirt_nop,
430 .alloc_pmd = paravirt_nop,
431 .alloc_pud = paravirt_nop,
432 .release_pte = paravirt_nop,
433 .release_pmd = paravirt_nop,
434 .release_pud = paravirt_nop,
435
436 .set_pte = native_set_pte,
437 .set_pte_at = native_set_pte_at,
438 .set_pmd = native_set_pmd,
439 .set_pmd_at = native_set_pmd_at,
440 .pte_update = paravirt_nop,
441 .pte_update_defer = paravirt_nop,
442 .pmd_update = paravirt_nop,
443 .pmd_update_defer = paravirt_nop,
444
445 .ptep_modify_prot_start = __ptep_modify_prot_start,
446 .ptep_modify_prot_commit = __ptep_modify_prot_commit,
447
448#if CONFIG_PGTABLE_LEVELS >= 3
449#ifdef CONFIG_X86_PAE
450 .set_pte_atomic = native_set_pte_atomic,
451 .pte_clear = native_pte_clear,
452 .pmd_clear = native_pmd_clear,
453#endif
454 .set_pud = native_set_pud,
455
456 .pmd_val = PTE_IDENT,
457 .make_pmd = PTE_IDENT,
458
459#if CONFIG_PGTABLE_LEVELS == 4
460 .pud_val = PTE_IDENT,
461 .make_pud = PTE_IDENT,
462
463 .set_pgd = native_set_pgd,
464#endif
465#endif
466
467 .pte_val = PTE_IDENT,
468 .pgd_val = PTE_IDENT,
469
470 .make_pte = PTE_IDENT,
471 .make_pgd = PTE_IDENT,
472
473 .dup_mmap = paravirt_nop,
474 .exit_mmap = paravirt_nop,
475 .activate_mm = paravirt_nop,
476
477 .lazy_mode = {
478 .enter = paravirt_nop,
479 .leave = paravirt_nop,
480 .flush = paravirt_nop,
481 },
482
483 .set_fixmap = native_set_fixmap,
484};
485
486EXPORT_SYMBOL_GPL(pv_time_ops);
487EXPORT_SYMBOL (pv_cpu_ops);
488EXPORT_SYMBOL (pv_mmu_ops);
489EXPORT_SYMBOL_GPL(pv_apic_ops);
490EXPORT_SYMBOL_GPL(pv_info);
491EXPORT_SYMBOL (pv_irq_ops);
492
