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v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*  Paravirtualization interfaces
  3    Copyright (C) 2006 Rusty Russell IBM Corporation
  4
 
 
 
 
 
 
 
 
 
 
 
 
 
  5
  6    2007 - x86_64 support added by Glauber de Oliveira Costa, Red Hat Inc
  7*/
  8
  9#include <linux/errno.h>
 10#include <linux/init.h>
 11#include <linux/export.h>
 12#include <linux/efi.h>
 13#include <linux/bcd.h>
 14#include <linux/highmem.h>
 15#include <linux/kprobes.h>
 16
 17#include <asm/bug.h>
 18#include <asm/paravirt.h>
 19#include <asm/debugreg.h>
 20#include <asm/desc.h>
 21#include <asm/setup.h>
 22#include <asm/pgtable.h>
 23#include <asm/time.h>
 24#include <asm/pgalloc.h>
 25#include <asm/irq.h>
 26#include <asm/delay.h>
 27#include <asm/fixmap.h>
 28#include <asm/apic.h>
 29#include <asm/tlbflush.h>
 30#include <asm/timer.h>
 31#include <asm/special_insns.h>
 32#include <asm/tlb.h>
 33
 34/*
 35 * nop stub, which must not clobber anything *including the stack* to
 36 * avoid confusing the entry prologues.
 37 */
 38extern void _paravirt_nop(void);
 39asm (".pushsection .entry.text, \"ax\"\n"
 40     ".global _paravirt_nop\n"
 41     "_paravirt_nop:\n\t"
 42     "ret\n\t"
 43     ".size _paravirt_nop, . - _paravirt_nop\n\t"
 44     ".type _paravirt_nop, @function\n\t"
 45     ".popsection");
 46
 
 
 
 
 
 
 
 
 
 
 
 47void __init default_banner(void)
 48{
 49	printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
 50	       pv_info.name);
 51}
 52
 53/* Undefined instruction for dealing with missing ops pointers. */
 54static const unsigned char ud2a[] = { 0x0f, 0x0b };
 55
 56struct branch {
 57	unsigned char opcode;
 58	u32 delta;
 59} __attribute__((packed));
 60
 61static unsigned paravirt_patch_call(void *insn_buff, const void *target,
 62				    unsigned long addr, unsigned len)
 
 
 63{
 64	const int call_len = 5;
 65	struct branch *b = insn_buff;
 66	unsigned long delta = (unsigned long)target - (addr+call_len);
 67
 68	if (len < call_len) {
 69		pr_warn("paravirt: Failed to patch indirect CALL at %ps\n", (void *)addr);
 70		/* Kernel might not be viable if patching fails, bail out: */
 71		BUG_ON(1);
 72	}
 73
 74	b->opcode = 0xe8; /* call */
 75	b->delta = delta;
 76	BUILD_BUG_ON(sizeof(*b) != call_len);
 77
 78	return call_len;
 79}
 80
 81#ifdef CONFIG_PARAVIRT_XXL
 82/* identity function, which can be inlined */
 83u64 notrace _paravirt_ident_64(u64 x)
 84{
 85	return x;
 86}
 87
 88static unsigned paravirt_patch_jmp(void *insn_buff, const void *target,
 89				   unsigned long addr, unsigned len)
 90{
 91	struct branch *b = insn_buff;
 92	unsigned long delta = (unsigned long)target - (addr+5);
 93
 94	if (len < 5) {
 95#ifdef CONFIG_RETPOLINE
 96		WARN_ONCE(1, "Failing to patch indirect JMP in %ps\n", (void *)addr);
 97#endif
 98		return len;	/* call too long for patch site */
 99	}
100
101	b->opcode = 0xe9;	/* jmp */
102	b->delta = delta;
103
104	return 5;
105}
106#endif
107
108DEFINE_STATIC_KEY_TRUE(virt_spin_lock_key);
109
110void __init native_pv_lock_init(void)
111{
112	if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))
113		static_branch_disable(&virt_spin_lock_key);
 
 
 
 
 
 
 
 
 
114}
115
116unsigned paravirt_patch_default(u8 type, void *insn_buff,
117				unsigned long addr, unsigned len)
118{
119	/*
120	 * Neat trick to map patch type back to the call within the
121	 * corresponding structure.
122	 */
123	void *opfunc = *((void **)&pv_ops + type);
124	unsigned ret;
125
126	if (opfunc == NULL)
127		/* If there's no function, patch it with a ud2a (BUG) */
128		ret = paravirt_patch_insns(insn_buff, len, ud2a, ud2a+sizeof(ud2a));
129	else if (opfunc == _paravirt_nop)
130		ret = 0;
131
132#ifdef CONFIG_PARAVIRT_XXL
133	/* identity functions just return their single argument */
 
 
134	else if (opfunc == _paravirt_ident_64)
135		ret = paravirt_patch_ident_64(insn_buff, len);
136
137	else if (type == PARAVIRT_PATCH(cpu.iret) ||
138		 type == PARAVIRT_PATCH(cpu.usergs_sysret64))
139		/* If operation requires a jmp, then jmp */
140		ret = paravirt_patch_jmp(insn_buff, opfunc, addr, len);
141#endif
142	else
143		/* Otherwise call the function. */
144		ret = paravirt_patch_call(insn_buff, opfunc, addr, len);
 
 
145
146	return ret;
147}
148
149unsigned paravirt_patch_insns(void *insn_buff, unsigned len,
150			      const char *start, const char *end)
151{
152	unsigned insn_len = end - start;
153
154	/* Alternative instruction is too large for the patch site and we cannot continue: */
155	BUG_ON(insn_len > len || start == NULL);
156
157	memcpy(insn_buff, start, insn_len);
158
159	return insn_len;
160}
161
162static void native_flush_tlb(void)
163{
164	__native_flush_tlb();
165}
166
167/*
168 * Global pages have to be flushed a bit differently. Not a real
169 * performance problem because this does not happen often.
170 */
171static void native_flush_tlb_global(void)
172{
173	__native_flush_tlb_global();
174}
175
176static void native_flush_tlb_one_user(unsigned long addr)
177{
178	__native_flush_tlb_one_user(addr);
179}
180
181struct static_key paravirt_steal_enabled;
182struct static_key paravirt_steal_rq_enabled;
183
184static u64 native_steal_clock(int cpu)
185{
186	return 0;
187}
188
189/* These are in entry.S */
190extern void native_iret(void);
191extern void native_usergs_sysret64(void);
192
193static struct resource reserve_ioports = {
194	.start = 0,
195	.end = IO_SPACE_LIMIT,
196	.name = "paravirt-ioport",
197	.flags = IORESOURCE_IO | IORESOURCE_BUSY,
198};
199
200/*
201 * Reserve the whole legacy IO space to prevent any legacy drivers
202 * from wasting time probing for their hardware.  This is a fairly
203 * brute-force approach to disabling all non-virtual drivers.
204 *
205 * Note that this must be called very early to have any effect.
206 */
207int paravirt_disable_iospace(void)
208{
209	return request_resource(&ioport_resource, &reserve_ioports);
210}
211
212static DEFINE_PER_CPU(enum paravirt_lazy_mode, paravirt_lazy_mode) = PARAVIRT_LAZY_NONE;
213
214static inline void enter_lazy(enum paravirt_lazy_mode mode)
215{
216	BUG_ON(this_cpu_read(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE);
217
218	this_cpu_write(paravirt_lazy_mode, mode);
219}
220
221static void leave_lazy(enum paravirt_lazy_mode mode)
222{
223	BUG_ON(this_cpu_read(paravirt_lazy_mode) != mode);
224
225	this_cpu_write(paravirt_lazy_mode, PARAVIRT_LAZY_NONE);
226}
227
228void paravirt_enter_lazy_mmu(void)
229{
230	enter_lazy(PARAVIRT_LAZY_MMU);
231}
232
233void paravirt_leave_lazy_mmu(void)
234{
235	leave_lazy(PARAVIRT_LAZY_MMU);
236}
237
238void paravirt_flush_lazy_mmu(void)
239{
240	preempt_disable();
241
242	if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
243		arch_leave_lazy_mmu_mode();
244		arch_enter_lazy_mmu_mode();
245	}
246
247	preempt_enable();
248}
249
250#ifdef CONFIG_PARAVIRT_XXL
251void paravirt_start_context_switch(struct task_struct *prev)
252{
253	BUG_ON(preemptible());
254
255	if (this_cpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) {
256		arch_leave_lazy_mmu_mode();
257		set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES);
258	}
259	enter_lazy(PARAVIRT_LAZY_CPU);
260}
261
262void paravirt_end_context_switch(struct task_struct *next)
263{
264	BUG_ON(preemptible());
265
266	leave_lazy(PARAVIRT_LAZY_CPU);
267
268	if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES))
269		arch_enter_lazy_mmu_mode();
270}
271#endif
272
273enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
274{
275	if (in_interrupt())
276		return PARAVIRT_LAZY_NONE;
277
278	return this_cpu_read(paravirt_lazy_mode);
279}
280
281struct pv_info pv_info = {
282	.name = "bare hardware",
283#ifdef CONFIG_PARAVIRT_XXL
284	.kernel_rpl = 0,
285	.shared_kernel_pmd = 1,	/* Only used when CONFIG_X86_PAE is set */
286
287#ifdef CONFIG_X86_64
288	.extra_user_64bit_cs = __USER_CS,
289#endif
290#endif
291};
292
293/* 64-bit pagetable entries */
294#define PTE_IDENT	__PV_IS_CALLEE_SAVE(_paravirt_ident_64)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
295
296struct paravirt_patch_template pv_ops = {
297	/* Init ops. */
298	.init.patch		= native_patch,
299
300	/* Time ops. */
301	.time.sched_clock	= native_sched_clock,
302	.time.steal_clock	= native_steal_clock,
303
304	/* Cpu ops. */
305	.cpu.io_delay		= native_io_delay,
306
307#ifdef CONFIG_PARAVIRT_XXL
308	.cpu.cpuid		= native_cpuid,
309	.cpu.get_debugreg	= native_get_debugreg,
310	.cpu.set_debugreg	= native_set_debugreg,
311	.cpu.read_cr0		= native_read_cr0,
312	.cpu.write_cr0		= native_write_cr0,
313	.cpu.write_cr4		= native_write_cr4,
314	.cpu.wbinvd		= native_wbinvd,
315	.cpu.read_msr		= native_read_msr,
316	.cpu.write_msr		= native_write_msr,
317	.cpu.read_msr_safe	= native_read_msr_safe,
318	.cpu.write_msr_safe	= native_write_msr_safe,
319	.cpu.read_pmc		= native_read_pmc,
320	.cpu.load_tr_desc	= native_load_tr_desc,
321	.cpu.set_ldt		= native_set_ldt,
322	.cpu.load_gdt		= native_load_gdt,
323	.cpu.load_idt		= native_load_idt,
324	.cpu.store_tr		= native_store_tr,
325	.cpu.load_tls		= native_load_tls,
326#ifdef CONFIG_X86_64
327	.cpu.load_gs_index	= native_load_gs_index,
328#endif
329	.cpu.write_ldt_entry	= native_write_ldt_entry,
330	.cpu.write_gdt_entry	= native_write_gdt_entry,
331	.cpu.write_idt_entry	= native_write_idt_entry,
332
333	.cpu.alloc_ldt		= paravirt_nop,
334	.cpu.free_ldt		= paravirt_nop,
335
336	.cpu.load_sp0		= native_load_sp0,
337
338#ifdef CONFIG_X86_64
339	.cpu.usergs_sysret64	= native_usergs_sysret64,
340#endif
341	.cpu.iret		= native_iret,
342	.cpu.swapgs		= native_swapgs,
 
 
 
 
 
 
 
 
 
 
 
 
343
344	.cpu.set_iopl_mask	= native_set_iopl_mask,
 
 
 
 
 
 
345
346	.cpu.start_context_switch	= paravirt_nop,
347	.cpu.end_context_switch		= paravirt_nop,
348
349	/* Irq ops. */
350	.irq.save_fl		= __PV_IS_CALLEE_SAVE(native_save_fl),
351	.irq.restore_fl		= __PV_IS_CALLEE_SAVE(native_restore_fl),
352	.irq.irq_disable	= __PV_IS_CALLEE_SAVE(native_irq_disable),
353	.irq.irq_enable		= __PV_IS_CALLEE_SAVE(native_irq_enable),
354	.irq.safe_halt		= native_safe_halt,
355	.irq.halt		= native_halt,
356#endif /* CONFIG_PARAVIRT_XXL */
357
358	/* Mmu ops. */
359	.mmu.flush_tlb_user	= native_flush_tlb,
360	.mmu.flush_tlb_kernel	= native_flush_tlb_global,
361	.mmu.flush_tlb_one_user	= native_flush_tlb_one_user,
362	.mmu.flush_tlb_others	= native_flush_tlb_others,
363	.mmu.tlb_remove_table	=
364			(void (*)(struct mmu_gather *, void *))tlb_remove_page,
365
366	.mmu.exit_mmap		= paravirt_nop,
367
368#ifdef CONFIG_PARAVIRT_XXL
369	.mmu.read_cr2		= __PV_IS_CALLEE_SAVE(native_read_cr2),
370	.mmu.write_cr2		= native_write_cr2,
371	.mmu.read_cr3		= __native_read_cr3,
372	.mmu.write_cr3		= native_write_cr3,
373
374	.mmu.pgd_alloc		= __paravirt_pgd_alloc,
375	.mmu.pgd_free		= paravirt_nop,
376
377	.mmu.alloc_pte		= paravirt_nop,
378	.mmu.alloc_pmd		= paravirt_nop,
379	.mmu.alloc_pud		= paravirt_nop,
380	.mmu.alloc_p4d		= paravirt_nop,
381	.mmu.release_pte	= paravirt_nop,
382	.mmu.release_pmd	= paravirt_nop,
383	.mmu.release_pud	= paravirt_nop,
384	.mmu.release_p4d	= paravirt_nop,
385
386	.mmu.set_pte		= native_set_pte,
387	.mmu.set_pte_at		= native_set_pte_at,
388	.mmu.set_pmd		= native_set_pmd,
389
390	.mmu.ptep_modify_prot_start	= __ptep_modify_prot_start,
391	.mmu.ptep_modify_prot_commit	= __ptep_modify_prot_commit,
392
393#if CONFIG_PGTABLE_LEVELS >= 3
394#ifdef CONFIG_X86_PAE
395	.mmu.set_pte_atomic	= native_set_pte_atomic,
396	.mmu.pte_clear		= native_pte_clear,
397	.mmu.pmd_clear		= native_pmd_clear,
398#endif
399	.mmu.set_pud		= native_set_pud,
400
401	.mmu.pmd_val		= PTE_IDENT,
402	.mmu.make_pmd		= PTE_IDENT,
403
404#if CONFIG_PGTABLE_LEVELS >= 4
405	.mmu.pud_val		= PTE_IDENT,
406	.mmu.make_pud		= PTE_IDENT,
407
408	.mmu.set_p4d		= native_set_p4d,
409
410#if CONFIG_PGTABLE_LEVELS >= 5
411	.mmu.p4d_val		= PTE_IDENT,
412	.mmu.make_p4d		= PTE_IDENT,
413
414	.mmu.set_pgd		= native_set_pgd,
415#endif /* CONFIG_PGTABLE_LEVELS >= 5 */
416#endif /* CONFIG_PGTABLE_LEVELS >= 4 */
417#endif /* CONFIG_PGTABLE_LEVELS >= 3 */
418
419	.mmu.pte_val		= PTE_IDENT,
420	.mmu.pgd_val		= PTE_IDENT,
421
422	.mmu.make_pte		= PTE_IDENT,
423	.mmu.make_pgd		= PTE_IDENT,
424
425	.mmu.dup_mmap		= paravirt_nop,
426	.mmu.activate_mm	= paravirt_nop,
427
428	.mmu.lazy_mode = {
429		.enter		= paravirt_nop,
430		.leave		= paravirt_nop,
431		.flush		= paravirt_nop,
 
 
 
 
432	},
433
434	.mmu.set_fixmap		= native_set_fixmap,
435#endif /* CONFIG_PARAVIRT_XXL */
436
437#if defined(CONFIG_PARAVIRT_SPINLOCKS)
438	/* Lock ops. */
439#ifdef CONFIG_SMP
440	.lock.queued_spin_lock_slowpath	= native_queued_spin_lock_slowpath,
441	.lock.queued_spin_unlock	=
442				PV_CALLEE_SAVE(__native_queued_spin_unlock),
443	.lock.wait			= paravirt_nop,
444	.lock.kick			= paravirt_nop,
445	.lock.vcpu_is_preempted		=
446				PV_CALLEE_SAVE(__native_vcpu_is_preempted),
447#endif /* SMP */
448#endif
449};
450
451#ifdef CONFIG_PARAVIRT_XXL
452/* At this point, native_get/set_debugreg has real function entries */
453NOKPROBE_SYMBOL(native_get_debugreg);
454NOKPROBE_SYMBOL(native_set_debugreg);
455NOKPROBE_SYMBOL(native_load_idt);
456#endif
457
458EXPORT_SYMBOL(pv_ops);
459EXPORT_SYMBOL_GPL(pv_info);
v4.6
 
  1/*  Paravirtualization interfaces
  2    Copyright (C) 2006 Rusty Russell IBM Corporation
  3
  4    This program is free software; you can redistribute it and/or modify
  5    it under the terms of the GNU General Public License as published by
  6    the Free Software Foundation; either version 2 of the License, or
  7    (at your option) any later version.
  8
  9    This program is distributed in the hope that it will be useful,
 10    but WITHOUT ANY WARRANTY; without even the implied warranty of
 11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 12    GNU General Public License for more details.
 13
 14    You should have received a copy of the GNU General Public License
 15    along with this program; if not, write to the Free Software
 16    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 17
 18    2007 - x86_64 support added by Glauber de Oliveira Costa, Red Hat Inc
 19*/
 20
 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 * nop stub, which must not clobber anything *including the stack* to
 46 * avoid confusing the entry prologues.
 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/* identity function, which can be inlined */
 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/* Undefined instruction for dealing with missing ops pointers. */
 75static const unsigned char ud2a[] = { 0x0f, 0x0b };
 76
 77struct branch {
 78	unsigned char opcode;
 79	u32 delta;
 80} __attribute__((packed));
 81
 82unsigned paravirt_patch_call(void *insnbuf,
 83			     const void *target, u16 tgt_clobbers,
 84			     unsigned long addr, u16 site_clobbers,
 85			     unsigned len)
 86{
 87	struct branch *b = insnbuf;
 88	unsigned long delta = (unsigned long)target - (addr+5);
 89
 90	if (tgt_clobbers & ~site_clobbers)
 91		return len;	/* target would clobber too much for this site */
 92	if (len < 5)
 93		return len;	/* call too long for patch site */
 
 
 94
 95	b->opcode = 0xe8; /* call */
 96	b->delta = delta;
 97	BUILD_BUG_ON(sizeof(*b) != 5);
 
 
 
 98
 99	return 5;
 
 
 
 
100}
101
102unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
103			    unsigned long addr, unsigned len)
104{
105	struct branch *b = insnbuf;
106	unsigned long delta = (unsigned long)target - (addr+5);
107
108	if (len < 5)
 
 
 
109		return len;	/* call too long for patch site */
 
110
111	b->opcode = 0xe9;	/* jmp */
112	b->delta = delta;
113
114	return 5;
115}
 
116
117/* Neat trick to map patch type back to the call within the
118 * corresponding structure. */
119static void *get_call_destination(u8 type)
120{
121	struct paravirt_patch_template tmpl = {
122		.pv_init_ops = pv_init_ops,
123		.pv_time_ops = pv_time_ops,
124		.pv_cpu_ops = pv_cpu_ops,
125		.pv_irq_ops = pv_irq_ops,
126		.pv_mmu_ops = pv_mmu_ops,
127#ifdef CONFIG_PARAVIRT_SPINLOCKS
128		.pv_lock_ops = pv_lock_ops,
129#endif
130	};
131	return *((void **)&tmpl + type);
132}
133
134unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
135				unsigned long addr, unsigned len)
136{
137	void *opfunc = get_call_destination(type);
 
 
 
 
138	unsigned ret;
139
140	if (opfunc == NULL)
141		/* If there's no function, patch it with a ud2a (BUG) */
142		ret = paravirt_patch_insns(insnbuf, len, ud2a, ud2a+sizeof(ud2a));
143	else if (opfunc == _paravirt_nop)
144		ret = 0;
145
 
146	/* identity functions just return their single argument */
147	else if (opfunc == _paravirt_ident_32)
148		ret = paravirt_patch_ident_32(insnbuf, len);
149	else if (opfunc == _paravirt_ident_64)
150		ret = paravirt_patch_ident_64(insnbuf, len);
151
152	else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
153		 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret64))
154		/* If operation requires a jmp, then jmp */
155		ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
 
156	else
157		/* Otherwise call the function; assume target could
158		   clobber any caller-save reg */
159		ret = paravirt_patch_call(insnbuf, opfunc, CLBR_ANY,
160					  addr, clobbers, len);
161
162	return ret;
163}
164
165unsigned paravirt_patch_insns(void *insnbuf, unsigned len,
166			      const char *start, const char *end)
167{
168	unsigned insn_len = end - start;
169
170	if (insn_len > len || start == NULL)
171		insn_len = len;
172	else
173		memcpy(insnbuf, start, insn_len);
174
175	return insn_len;
176}
177
178static void native_flush_tlb(void)
179{
180	__native_flush_tlb();
181}
182
183/*
184 * Global pages have to be flushed a bit differently. Not a real
185 * performance problem because this does not happen often.
186 */
187static void native_flush_tlb_global(void)
188{
189	__native_flush_tlb_global();
190}
191
192static void native_flush_tlb_single(unsigned long addr)
193{
194	__native_flush_tlb_single(addr);
195}
196
197struct static_key paravirt_steal_enabled;
198struct static_key paravirt_steal_rq_enabled;
199
200static u64 native_steal_clock(int cpu)
201{
202	return 0;
203}
204
205/* These are in entry.S */
206extern void native_iret(void);
207extern void native_usergs_sysret64(void);
208
209static struct resource reserve_ioports = {
210	.start = 0,
211	.end = IO_SPACE_LIMIT,
212	.name = "paravirt-ioport",
213	.flags = IORESOURCE_IO | IORESOURCE_BUSY,
214};
215
216/*
217 * Reserve the whole legacy IO space to prevent any legacy drivers
218 * from wasting time probing for their hardware.  This is a fairly
219 * brute-force approach to disabling all non-virtual drivers.
220 *
221 * Note that this must be called very early to have any effect.
222 */
223int paravirt_disable_iospace(void)
224{
225	return request_resource(&ioport_resource, &reserve_ioports);
226}
227
228static DEFINE_PER_CPU(enum paravirt_lazy_mode, paravirt_lazy_mode) = PARAVIRT_LAZY_NONE;
229
230static inline void enter_lazy(enum paravirt_lazy_mode mode)
231{
232	BUG_ON(this_cpu_read(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE);
233
234	this_cpu_write(paravirt_lazy_mode, mode);
235}
236
237static void leave_lazy(enum paravirt_lazy_mode mode)
238{
239	BUG_ON(this_cpu_read(paravirt_lazy_mode) != mode);
240
241	this_cpu_write(paravirt_lazy_mode, PARAVIRT_LAZY_NONE);
242}
243
244void paravirt_enter_lazy_mmu(void)
245{
246	enter_lazy(PARAVIRT_LAZY_MMU);
247}
248
249void paravirt_leave_lazy_mmu(void)
250{
251	leave_lazy(PARAVIRT_LAZY_MMU);
252}
253
254void paravirt_flush_lazy_mmu(void)
255{
256	preempt_disable();
257
258	if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
259		arch_leave_lazy_mmu_mode();
260		arch_enter_lazy_mmu_mode();
261	}
262
263	preempt_enable();
264}
265
 
266void paravirt_start_context_switch(struct task_struct *prev)
267{
268	BUG_ON(preemptible());
269
270	if (this_cpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) {
271		arch_leave_lazy_mmu_mode();
272		set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES);
273	}
274	enter_lazy(PARAVIRT_LAZY_CPU);
275}
276
277void paravirt_end_context_switch(struct task_struct *next)
278{
279	BUG_ON(preemptible());
280
281	leave_lazy(PARAVIRT_LAZY_CPU);
282
283	if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES))
284		arch_enter_lazy_mmu_mode();
285}
 
286
287enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
288{
289	if (in_interrupt())
290		return PARAVIRT_LAZY_NONE;
291
292	return this_cpu_read(paravirt_lazy_mode);
293}
294
295struct pv_info pv_info = {
296	.name = "bare hardware",
297	.paravirt_enabled = 0,
298	.kernel_rpl = 0,
299	.shared_kernel_pmd = 1,	/* Only used when CONFIG_X86_PAE is set */
300
301#ifdef CONFIG_X86_64
302	.extra_user_64bit_cs = __USER_CS,
303#endif
 
304};
305
306struct pv_init_ops pv_init_ops = {
307	.patch = native_patch,
308};
309
310struct pv_time_ops pv_time_ops = {
311	.sched_clock = native_sched_clock,
312	.steal_clock = native_steal_clock,
313};
314
315__visible struct pv_irq_ops pv_irq_ops = {
316	.save_fl = __PV_IS_CALLEE_SAVE(native_save_fl),
317	.restore_fl = __PV_IS_CALLEE_SAVE(native_restore_fl),
318	.irq_disable = __PV_IS_CALLEE_SAVE(native_irq_disable),
319	.irq_enable = __PV_IS_CALLEE_SAVE(native_irq_enable),
320	.safe_halt = native_safe_halt,
321	.halt = native_halt,
322#ifdef CONFIG_X86_64
323	.adjust_exception_frame = paravirt_nop,
324#endif
325};
326
327__visible struct pv_cpu_ops pv_cpu_ops = {
328	.cpuid = native_cpuid,
329	.get_debugreg = native_get_debugreg,
330	.set_debugreg = native_set_debugreg,
331	.clts = native_clts,
332	.read_cr0 = native_read_cr0,
333	.write_cr0 = native_write_cr0,
334	.read_cr4 = native_read_cr4,
335	.read_cr4_safe = native_read_cr4_safe,
336	.write_cr4 = native_write_cr4,
337#ifdef CONFIG_X86_64
338	.read_cr8 = native_read_cr8,
339	.write_cr8 = native_write_cr8,
340#endif
341	.wbinvd = native_wbinvd,
342	.read_msr = native_read_msr_safe,
343	.write_msr = native_write_msr_safe,
344	.read_pmc = native_read_pmc,
345	.load_tr_desc = native_load_tr_desc,
346	.set_ldt = native_set_ldt,
347	.load_gdt = native_load_gdt,
348	.load_idt = native_load_idt,
349	.store_idt = native_store_idt,
350	.store_tr = native_store_tr,
351	.load_tls = native_load_tls,
 
 
 
 
 
352#ifdef CONFIG_X86_64
353	.load_gs_index = native_load_gs_index,
354#endif
355	.write_ldt_entry = native_write_ldt_entry,
356	.write_gdt_entry = native_write_gdt_entry,
357	.write_idt_entry = native_write_idt_entry,
358
359	.alloc_ldt = paravirt_nop,
360	.free_ldt = paravirt_nop,
361
362	.load_sp0 = native_load_sp0,
363
364#ifdef CONFIG_X86_64
365	.usergs_sysret64 = native_usergs_sysret64,
366#endif
367	.iret = native_iret,
368	.swapgs = native_swapgs,
369
370	.set_iopl_mask = native_set_iopl_mask,
371	.io_delay = native_io_delay,
372
373	.start_context_switch = paravirt_nop,
374	.end_context_switch = paravirt_nop,
375};
376
377/* At this point, native_get/set_debugreg has real function entries */
378NOKPROBE_SYMBOL(native_get_debugreg);
379NOKPROBE_SYMBOL(native_set_debugreg);
380NOKPROBE_SYMBOL(native_load_idt);
381
382#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_PAE)
383/* 32-bit pagetable entries */
384#define PTE_IDENT	__PV_IS_CALLEE_SAVE(_paravirt_ident_32)
385#else
386/* 64-bit pagetable entries */
387#define PTE_IDENT	__PV_IS_CALLEE_SAVE(_paravirt_ident_64)
388#endif
389
390struct pv_mmu_ops pv_mmu_ops = {
 
391
392	.read_cr2 = native_read_cr2,
393	.write_cr2 = native_write_cr2,
394	.read_cr3 = native_read_cr3,
395	.write_cr3 = native_write_cr3,
396
397	.flush_tlb_user = native_flush_tlb,
398	.flush_tlb_kernel = native_flush_tlb_global,
399	.flush_tlb_single = native_flush_tlb_single,
400	.flush_tlb_others = native_flush_tlb_others,
401
402	.pgd_alloc = __paravirt_pgd_alloc,
403	.pgd_free = paravirt_nop,
404
405	.alloc_pte = paravirt_nop,
406	.alloc_pmd = paravirt_nop,
407	.alloc_pud = paravirt_nop,
408	.release_pte = paravirt_nop,
409	.release_pmd = paravirt_nop,
410	.release_pud = paravirt_nop,
411
412	.set_pte = native_set_pte,
413	.set_pte_at = native_set_pte_at,
414	.set_pmd = native_set_pmd,
415	.set_pmd_at = native_set_pmd_at,
416	.pte_update = paravirt_nop,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
417
418	.ptep_modify_prot_start = __ptep_modify_prot_start,
419	.ptep_modify_prot_commit = __ptep_modify_prot_commit,
420
421#if CONFIG_PGTABLE_LEVELS >= 3
422#ifdef CONFIG_X86_PAE
423	.set_pte_atomic = native_set_pte_atomic,
424	.pte_clear = native_pte_clear,
425	.pmd_clear = native_pmd_clear,
426#endif
427	.set_pud = native_set_pud,
428
429	.pmd_val = PTE_IDENT,
430	.make_pmd = PTE_IDENT,
431
432#if CONFIG_PGTABLE_LEVELS == 4
433	.pud_val = PTE_IDENT,
434	.make_pud = PTE_IDENT,
435
436	.set_pgd = native_set_pgd,
437#endif
 
 
 
 
 
 
 
438#endif /* CONFIG_PGTABLE_LEVELS >= 3 */
439
440	.pte_val = PTE_IDENT,
441	.pgd_val = PTE_IDENT,
 
 
 
442
443	.make_pte = PTE_IDENT,
444	.make_pgd = PTE_IDENT,
445
446	.dup_mmap = paravirt_nop,
447	.exit_mmap = paravirt_nop,
448	.activate_mm = paravirt_nop,
449
450	.lazy_mode = {
451		.enter = paravirt_nop,
452		.leave = paravirt_nop,
453		.flush = paravirt_nop,
454	},
455
456	.set_fixmap = native_set_fixmap,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
457};
458
459EXPORT_SYMBOL_GPL(pv_time_ops);
460EXPORT_SYMBOL    (pv_cpu_ops);
461EXPORT_SYMBOL    (pv_mmu_ops);
 
 
 
 
 
462EXPORT_SYMBOL_GPL(pv_info);
463EXPORT_SYMBOL    (pv_irq_ops);