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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
45
46
47
48extern void _paravirt_nop(void);
49asm (".pushsection .entry.text, \"ax\"\n"
50 ".global _paravirt_nop\n"
51 "_paravirt_nop:\n\t"
52 "ret\n\t"
53 ".size _paravirt_nop, . - _paravirt_nop\n\t"
54 ".type _paravirt_nop, @function\n\t"
55 ".popsection");
56
57
58u32 _paravirt_ident_32(u32 x)
59{
60 return x;
61}
62
63u64 _paravirt_ident_64(u64 x)
64{
65 return x;
66}
67
68void __init default_banner(void)
69{
70 printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
71 pv_info.name);
72}
73
74
75static const unsigned char ud2a[] = { 0x0f, 0x0b };
76
77unsigned paravirt_patch_nop(void)
78{
79 return 0;
80}
81
82unsigned paravirt_patch_ignore(unsigned len)
83{
84 return len;
85}
86
87struct branch {
88 unsigned char opcode;
89 u32 delta;
90} __attribute__((packed));
91
92unsigned paravirt_patch_call(void *insnbuf,
93 const void *target, u16 tgt_clobbers,
94 unsigned long addr, u16 site_clobbers,
95 unsigned len)
96{
97 struct branch *b = insnbuf;
98 unsigned long delta = (unsigned long)target - (addr+5);
99
100 if (tgt_clobbers & ~site_clobbers)
101 return len;
102 if (len < 5)
103 return len;
104
105 b->opcode = 0xe8;
106 b->delta = delta;
107 BUILD_BUG_ON(sizeof(*b) != 5);
108
109 return 5;
110}
111
112unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
113 unsigned long addr, unsigned len)
114{
115 struct branch *b = insnbuf;
116 unsigned long delta = (unsigned long)target - (addr+5);
117
118 if (len < 5)
119 return len;
120
121 b->opcode = 0xe9;
122 b->delta = delta;
123
124 return 5;
125}
126
127
128
129static void *get_call_destination(u8 type)
130{
131 struct paravirt_patch_template tmpl = {
132 .pv_init_ops = pv_init_ops,
133 .pv_time_ops = pv_time_ops,
134 .pv_cpu_ops = pv_cpu_ops,
135 .pv_irq_ops = pv_irq_ops,
136 .pv_apic_ops = pv_apic_ops,
137 .pv_mmu_ops = pv_mmu_ops,
138#ifdef CONFIG_PARAVIRT_SPINLOCKS
139 .pv_lock_ops = pv_lock_ops,
140#endif
141 };
142 return *((void **)&tmpl + type);
143}
144
145unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
146 unsigned long addr, unsigned len)
147{
148 void *opfunc = get_call_destination(type);
149 unsigned ret;
150
151 if (opfunc == NULL)
152
153 ret = paravirt_patch_insns(insnbuf, len, ud2a, ud2a+sizeof(ud2a));
154 else if (opfunc == _paravirt_nop)
155
156 ret = paravirt_patch_nop();
157
158
159 else if (opfunc == _paravirt_ident_32)
160 ret = paravirt_patch_ident_32(insnbuf, len);
161 else if (opfunc == _paravirt_ident_64)
162 ret = paravirt_patch_ident_64(insnbuf, len);
163
164 else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
165#ifdef CONFIG_X86_32
166 type == PARAVIRT_PATCH(pv_cpu_ops.irq_enable_sysexit) ||
167#endif
168 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret32) ||
169 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret64))
170
171 ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
172 else
173
174
175 ret = paravirt_patch_call(insnbuf, opfunc, CLBR_ANY,
176 addr, clobbers, len);
177
178 return ret;
179}
180
181unsigned paravirt_patch_insns(void *insnbuf, unsigned len,
182 const char *start, const char *end)
183{
184 unsigned insn_len = end - start;
185
186 if (insn_len > len || start == NULL)
187 insn_len = len;
188 else
189 memcpy(insnbuf, start, insn_len);
190
191 return insn_len;
192}
193
194static void native_flush_tlb(void)
195{
196 __native_flush_tlb();
197}
198
199
200
201
202
203static void native_flush_tlb_global(void)
204{
205 __native_flush_tlb_global();
206}
207
208static void native_flush_tlb_single(unsigned long addr)
209{
210 __native_flush_tlb_single(addr);
211}
212
213struct static_key paravirt_steal_enabled;
214struct static_key paravirt_steal_rq_enabled;
215
216static u64 native_steal_clock(int cpu)
217{
218 return 0;
219}
220
221
222extern void native_iret(void);
223extern void native_irq_enable_sysexit(void);
224extern void native_usergs_sysret32(void);
225extern void native_usergs_sysret64(void);
226
227static struct resource reserve_ioports = {
228 .start = 0,
229 .end = IO_SPACE_LIMIT,
230 .name = "paravirt-ioport",
231 .flags = IORESOURCE_IO | IORESOURCE_BUSY,
232};
233
234
235
236
237
238
239
240
241int paravirt_disable_iospace(void)
242{
243 return request_resource(&ioport_resource, &reserve_ioports);
244}
245
246static DEFINE_PER_CPU(enum paravirt_lazy_mode, paravirt_lazy_mode) = PARAVIRT_LAZY_NONE;
247
248static inline void enter_lazy(enum paravirt_lazy_mode mode)
249{
250 BUG_ON(this_cpu_read(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE);
251
252 this_cpu_write(paravirt_lazy_mode, mode);
253}
254
255static void leave_lazy(enum paravirt_lazy_mode mode)
256{
257 BUG_ON(this_cpu_read(paravirt_lazy_mode) != mode);
258
259 this_cpu_write(paravirt_lazy_mode, PARAVIRT_LAZY_NONE);
260}
261
262void paravirt_enter_lazy_mmu(void)
263{
264 enter_lazy(PARAVIRT_LAZY_MMU);
265}
266
267void paravirt_leave_lazy_mmu(void)
268{
269 leave_lazy(PARAVIRT_LAZY_MMU);
270}
271
272void paravirt_flush_lazy_mmu(void)
273{
274 preempt_disable();
275
276 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
277 arch_leave_lazy_mmu_mode();
278 arch_enter_lazy_mmu_mode();
279 }
280
281 preempt_enable();
282}
283
284void paravirt_start_context_switch(struct task_struct *prev)
285{
286 BUG_ON(preemptible());
287
288 if (this_cpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) {
289 arch_leave_lazy_mmu_mode();
290 set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES);
291 }
292 enter_lazy(PARAVIRT_LAZY_CPU);
293}
294
295void paravirt_end_context_switch(struct task_struct *next)
296{
297 BUG_ON(preemptible());
298
299 leave_lazy(PARAVIRT_LAZY_CPU);
300
301 if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES))
302 arch_enter_lazy_mmu_mode();
303}
304
305enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
306{
307 if (in_interrupt())
308 return PARAVIRT_LAZY_NONE;
309
310 return this_cpu_read(paravirt_lazy_mode);
311}
312
313struct pv_info pv_info = {
314 .name = "bare hardware",
315 .paravirt_enabled = 0,
316 .kernel_rpl = 0,
317 .shared_kernel_pmd = 1,
318
319#ifdef CONFIG_X86_64
320 .extra_user_64bit_cs = __USER_CS,
321#endif
322};
323
324struct pv_init_ops pv_init_ops = {
325 .patch = native_patch,
326};
327
328struct pv_time_ops pv_time_ops = {
329 .sched_clock = native_sched_clock,
330 .steal_clock = native_steal_clock,
331};
332
333__visible struct pv_irq_ops pv_irq_ops = {
334 .save_fl = __PV_IS_CALLEE_SAVE(native_save_fl),
335 .restore_fl = __PV_IS_CALLEE_SAVE(native_restore_fl),
336 .irq_disable = __PV_IS_CALLEE_SAVE(native_irq_disable),
337 .irq_enable = __PV_IS_CALLEE_SAVE(native_irq_enable),
338 .safe_halt = native_safe_halt,
339 .halt = native_halt,
340#ifdef CONFIG_X86_64
341 .adjust_exception_frame = paravirt_nop,
342#endif
343};
344
345__visible struct pv_cpu_ops pv_cpu_ops = {
346 .cpuid = native_cpuid,
347 .get_debugreg = native_get_debugreg,
348 .set_debugreg = native_set_debugreg,
349 .clts = native_clts,
350 .read_cr0 = native_read_cr0,
351 .write_cr0 = native_write_cr0,
352 .read_cr4 = native_read_cr4,
353 .read_cr4_safe = native_read_cr4_safe,
354 .write_cr4 = native_write_cr4,
355#ifdef CONFIG_X86_64
356 .read_cr8 = native_read_cr8,
357 .write_cr8 = native_write_cr8,
358#endif
359 .wbinvd = native_wbinvd,
360 .read_msr = native_read_msr_safe,
361 .write_msr = native_write_msr_safe,
362 .read_pmc = native_read_pmc,
363 .load_tr_desc = native_load_tr_desc,
364 .set_ldt = native_set_ldt,
365 .load_gdt = native_load_gdt,
366 .load_idt = native_load_idt,
367 .store_idt = native_store_idt,
368 .store_tr = native_store_tr,
369 .load_tls = native_load_tls,
370#ifdef CONFIG_X86_64
371 .load_gs_index = native_load_gs_index,
372#endif
373 .write_ldt_entry = native_write_ldt_entry,
374 .write_gdt_entry = native_write_gdt_entry,
375 .write_idt_entry = native_write_idt_entry,
376
377 .alloc_ldt = paravirt_nop,
378 .free_ldt = paravirt_nop,
379
380 .load_sp0 = native_load_sp0,
381
382#if defined(CONFIG_X86_32)
383 .irq_enable_sysexit = native_irq_enable_sysexit,
384#endif
385#ifdef CONFIG_X86_64
386#ifdef CONFIG_IA32_EMULATION
387 .usergs_sysret32 = native_usergs_sysret32,
388#endif
389 .usergs_sysret64 = native_usergs_sysret64,
390#endif
391 .iret = native_iret,
392 .swapgs = native_swapgs,
393
394 .set_iopl_mask = native_set_iopl_mask,
395 .io_delay = native_io_delay,
396
397 .start_context_switch = paravirt_nop,
398 .end_context_switch = paravirt_nop,
399};
400
401
402NOKPROBE_SYMBOL(native_get_debugreg);
403NOKPROBE_SYMBOL(native_set_debugreg);
404NOKPROBE_SYMBOL(native_load_idt);
405
406struct pv_apic_ops pv_apic_ops = {
407#ifdef CONFIG_X86_LOCAL_APIC
408 .startup_ipi_hook = paravirt_nop,
409#endif
410};
411
412#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_PAE)
413
414#define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_32)
415#else
416
417#define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_64)
418#endif
419
420struct pv_mmu_ops pv_mmu_ops = {
421
422 .read_cr2 = native_read_cr2,
423 .write_cr2 = native_write_cr2,
424 .read_cr3 = native_read_cr3,
425 .write_cr3 = native_write_cr3,
426
427 .flush_tlb_user = native_flush_tlb,
428 .flush_tlb_kernel = native_flush_tlb_global,
429 .flush_tlb_single = native_flush_tlb_single,
430 .flush_tlb_others = native_flush_tlb_others,
431
432 .pgd_alloc = __paravirt_pgd_alloc,
433 .pgd_free = paravirt_nop,
434
435 .alloc_pte = paravirt_nop,
436 .alloc_pmd = paravirt_nop,
437 .alloc_pud = paravirt_nop,
438 .release_pte = paravirt_nop,
439 .release_pmd = paravirt_nop,
440 .release_pud = paravirt_nop,
441
442 .set_pte = native_set_pte,
443 .set_pte_at = native_set_pte_at,
444 .set_pmd = native_set_pmd,
445 .set_pmd_at = native_set_pmd_at,
446 .pte_update = paravirt_nop,
447 .pte_update_defer = paravirt_nop,
448 .pmd_update = paravirt_nop,
449 .pmd_update_defer = paravirt_nop,
450
451 .ptep_modify_prot_start = __ptep_modify_prot_start,
452 .ptep_modify_prot_commit = __ptep_modify_prot_commit,
453
454#if CONFIG_PGTABLE_LEVELS >= 3
455#ifdef CONFIG_X86_PAE
456 .set_pte_atomic = native_set_pte_atomic,
457 .pte_clear = native_pte_clear,
458 .pmd_clear = native_pmd_clear,
459#endif
460 .set_pud = native_set_pud,
461
462 .pmd_val = PTE_IDENT,
463 .make_pmd = PTE_IDENT,
464
465#if CONFIG_PGTABLE_LEVELS == 4
466 .pud_val = PTE_IDENT,
467 .make_pud = PTE_IDENT,
468
469 .set_pgd = native_set_pgd,
470#endif
471#endif
472
473 .pte_val = PTE_IDENT,
474 .pgd_val = PTE_IDENT,
475
476 .make_pte = PTE_IDENT,
477 .make_pgd = PTE_IDENT,
478
479 .dup_mmap = paravirt_nop,
480 .exit_mmap = paravirt_nop,
481 .activate_mm = paravirt_nop,
482
483 .lazy_mode = {
484 .enter = paravirt_nop,
485 .leave = paravirt_nop,
486 .flush = paravirt_nop,
487 },
488
489 .set_fixmap = native_set_fixmap,
490};
491
492EXPORT_SYMBOL_GPL(pv_time_ops);
493EXPORT_SYMBOL (pv_cpu_ops);
494EXPORT_SYMBOL (pv_mmu_ops);
495EXPORT_SYMBOL_GPL(pv_apic_ops);
496EXPORT_SYMBOL_GPL(pv_info);
497EXPORT_SYMBOL (pv_irq_ops);
498
