Linux Audio

Check our new training course

Embedded Linux training

Mar 10-20, 2025, special US time zones
Register
Loading...
v4.17
  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/init.h>
 23#include <linux/export.h>
 24#include <linux/efi.h>
 25#include <linux/bcd.h>
 26#include <linux/highmem.h>
 27#include <linux/kprobes.h>
 28
 29#include <asm/bug.h>
 30#include <asm/paravirt.h>
 31#include <asm/debugreg.h>
 32#include <asm/desc.h>
 33#include <asm/setup.h>
 34#include <asm/pgtable.h>
 35#include <asm/time.h>
 36#include <asm/pgalloc.h>
 37#include <asm/irq.h>
 38#include <asm/delay.h>
 39#include <asm/fixmap.h>
 40#include <asm/apic.h>
 41#include <asm/tlbflush.h>
 42#include <asm/timer.h>
 43#include <asm/special_insns.h>
 44
 45/*
 46 * nop stub, which must not clobber anything *including the stack* to
 47 * avoid confusing the entry prologues.
 48 */
 49extern void _paravirt_nop(void);
 50asm (".pushsection .entry.text, \"ax\"\n"
 51     ".global _paravirt_nop\n"
 52     "_paravirt_nop:\n\t"
 53     "ret\n\t"
 54     ".size _paravirt_nop, . - _paravirt_nop\n\t"
 55     ".type _paravirt_nop, @function\n\t"
 56     ".popsection");
 57
 58/* identity function, which can be inlined */
 59u32 notrace _paravirt_ident_32(u32 x)
 60{
 61	return x;
 62}
 63
 64u64 notrace _paravirt_ident_64(u64 x)
 65{
 66	return x;
 67}
 68
 69void __init default_banner(void)
 70{
 71	printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
 72	       pv_info.name);
 73}
 74
 
 
 
 
 
 75/* Undefined instruction for dealing with missing ops pointers. */
 76static const unsigned char ud2a[] = { 0x0f, 0x0b };
 77
 
 
 
 
 
 
 
 
 
 
 78struct branch {
 79	unsigned char opcode;
 80	u32 delta;
 81} __attribute__((packed));
 82
 83unsigned paravirt_patch_call(void *insnbuf,
 84			     const void *target, u16 tgt_clobbers,
 85			     unsigned long addr, u16 site_clobbers,
 86			     unsigned len)
 87{
 88	struct branch *b = insnbuf;
 89	unsigned long delta = (unsigned long)target - (addr+5);
 90
 91	if (tgt_clobbers & ~site_clobbers)
 92		return len;	/* target would clobber too much for this site */
 93	if (len < 5)
 94		return len;	/* call too long for patch site */
 95
 96	b->opcode = 0xe8; /* call */
 97	b->delta = delta;
 98	BUILD_BUG_ON(sizeof(*b) != 5);
 99
100	return 5;
101}
102
103unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
104			    unsigned long addr, unsigned len)
105{
106	struct branch *b = insnbuf;
107	unsigned long delta = (unsigned long)target - (addr+5);
108
109	if (len < 5)
110		return len;	/* call too long for patch site */
111
112	b->opcode = 0xe9;	/* jmp */
113	b->delta = delta;
114
115	return 5;
116}
117
118DEFINE_STATIC_KEY_TRUE(virt_spin_lock_key);
119
120void __init native_pv_lock_init(void)
121{
122	if (!static_cpu_has(X86_FEATURE_HYPERVISOR))
123		static_branch_disable(&virt_spin_lock_key);
124}
125
126/*
127 * Neat trick to map patch type back to the call within the
128 * corresponding structure.
129 */
130static void *get_call_destination(u8 type)
131{
132	struct paravirt_patch_template tmpl = {
133		.pv_init_ops = pv_init_ops,
134		.pv_time_ops = pv_time_ops,
135		.pv_cpu_ops = pv_cpu_ops,
136		.pv_irq_ops = pv_irq_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		/* If there's no function, patch it with a ud2a (BUG) */
153		ret = paravirt_patch_insns(insnbuf, len, ud2a, ud2a+sizeof(ud2a));
154	else if (opfunc == _paravirt_nop)
155		ret = 0;
 
156
157	/* identity functions just return their single argument */
158	else if (opfunc == _paravirt_ident_32)
159		ret = paravirt_patch_ident_32(insnbuf, len);
160	else if (opfunc == _paravirt_ident_64)
161		ret = paravirt_patch_ident_64(insnbuf, len);
162
163	else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
 
 
164		 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret64))
165		/* If operation requires a jmp, then jmp */
166		ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
167	else
168		/* Otherwise call the function; assume target could
169		   clobber any caller-save reg */
170		ret = paravirt_patch_call(insnbuf, opfunc, CLBR_ANY,
171					  addr, clobbers, len);
172
173	return ret;
174}
175
176unsigned paravirt_patch_insns(void *insnbuf, unsigned len,
177			      const char *start, const char *end)
178{
179	unsigned insn_len = end - start;
180
181	if (insn_len > len || start == NULL)
182		insn_len = len;
183	else
184		memcpy(insnbuf, start, insn_len);
185
186	return insn_len;
187}
188
189static void native_flush_tlb(void)
190{
191	__native_flush_tlb();
192}
193
194/*
195 * Global pages have to be flushed a bit differently. Not a real
196 * performance problem because this does not happen often.
197 */
198static void native_flush_tlb_global(void)
199{
200	__native_flush_tlb_global();
201}
202
203static void native_flush_tlb_one_user(unsigned long addr)
204{
205	__native_flush_tlb_one_user(addr);
206}
207
208struct static_key paravirt_steal_enabled;
209struct static_key paravirt_steal_rq_enabled;
210
211static u64 native_steal_clock(int cpu)
212{
213	return 0;
214}
215
216/* These are in entry.S */
217extern void native_iret(void);
 
 
218extern void native_usergs_sysret64(void);
219
220static struct resource reserve_ioports = {
221	.start = 0,
222	.end = IO_SPACE_LIMIT,
223	.name = "paravirt-ioport",
224	.flags = IORESOURCE_IO | IORESOURCE_BUSY,
225};
226
227/*
228 * Reserve the whole legacy IO space to prevent any legacy drivers
229 * from wasting time probing for their hardware.  This is a fairly
230 * brute-force approach to disabling all non-virtual drivers.
231 *
232 * Note that this must be called very early to have any effect.
233 */
234int paravirt_disable_iospace(void)
235{
236	return request_resource(&ioport_resource, &reserve_ioports);
237}
238
239static DEFINE_PER_CPU(enum paravirt_lazy_mode, paravirt_lazy_mode) = PARAVIRT_LAZY_NONE;
240
241static inline void enter_lazy(enum paravirt_lazy_mode mode)
242{
243	BUG_ON(this_cpu_read(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE);
244
245	this_cpu_write(paravirt_lazy_mode, mode);
246}
247
248static void leave_lazy(enum paravirt_lazy_mode mode)
249{
250	BUG_ON(this_cpu_read(paravirt_lazy_mode) != mode);
251
252	this_cpu_write(paravirt_lazy_mode, PARAVIRT_LAZY_NONE);
253}
254
255void paravirt_enter_lazy_mmu(void)
256{
257	enter_lazy(PARAVIRT_LAZY_MMU);
258}
259
260void paravirt_leave_lazy_mmu(void)
261{
262	leave_lazy(PARAVIRT_LAZY_MMU);
263}
264
265void paravirt_flush_lazy_mmu(void)
266{
267	preempt_disable();
268
269	if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
270		arch_leave_lazy_mmu_mode();
271		arch_enter_lazy_mmu_mode();
272	}
273
274	preempt_enable();
275}
276
277void paravirt_start_context_switch(struct task_struct *prev)
278{
279	BUG_ON(preemptible());
280
281	if (this_cpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) {
282		arch_leave_lazy_mmu_mode();
283		set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES);
284	}
285	enter_lazy(PARAVIRT_LAZY_CPU);
286}
287
288void paravirt_end_context_switch(struct task_struct *next)
289{
290	BUG_ON(preemptible());
291
292	leave_lazy(PARAVIRT_LAZY_CPU);
293
294	if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES))
295		arch_enter_lazy_mmu_mode();
296}
297
298enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
299{
300	if (in_interrupt())
301		return PARAVIRT_LAZY_NONE;
302
303	return this_cpu_read(paravirt_lazy_mode);
304}
305
 
 
 
 
 
 
 
 
 
 
 
 
306struct pv_info pv_info = {
307	.name = "bare hardware",
 
308	.kernel_rpl = 0,
309	.shared_kernel_pmd = 1,	/* Only used when CONFIG_X86_PAE is set */
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};
333
334__visible struct pv_cpu_ops pv_cpu_ops = {
335	.cpuid = native_cpuid,
336	.get_debugreg = native_get_debugreg,
337	.set_debugreg = native_set_debugreg,
 
338	.read_cr0 = native_read_cr0,
339	.write_cr0 = native_write_cr0,
 
 
340	.write_cr4 = native_write_cr4,
341#ifdef CONFIG_X86_64
342	.read_cr8 = native_read_cr8,
343	.write_cr8 = native_write_cr8,
344#endif
345	.wbinvd = native_wbinvd,
346	.read_msr = native_read_msr,
347	.write_msr = native_write_msr,
348	.read_msr_safe = native_read_msr_safe,
349	.write_msr_safe = native_write_msr_safe,
 
350	.read_pmc = native_read_pmc,
 
351	.load_tr_desc = native_load_tr_desc,
352	.set_ldt = native_set_ldt,
353	.load_gdt = native_load_gdt,
354	.load_idt = native_load_idt,
 
 
355	.store_tr = native_store_tr,
356	.load_tls = native_load_tls,
357#ifdef CONFIG_X86_64
358	.load_gs_index = native_load_gs_index,
359#endif
360	.write_ldt_entry = native_write_ldt_entry,
361	.write_gdt_entry = native_write_gdt_entry,
362	.write_idt_entry = native_write_idt_entry,
363
364	.alloc_ldt = paravirt_nop,
365	.free_ldt = paravirt_nop,
366
367	.load_sp0 = native_load_sp0,
368
 
 
 
369#ifdef CONFIG_X86_64
 
 
 
370	.usergs_sysret64 = native_usergs_sysret64,
371#endif
372	.iret = native_iret,
373	.swapgs = native_swapgs,
374
375	.set_iopl_mask = native_set_iopl_mask,
376	.io_delay = native_io_delay,
377
378	.start_context_switch = paravirt_nop,
379	.end_context_switch = paravirt_nop,
380};
381
382/* At this point, native_get/set_debugreg has real function entries */
383NOKPROBE_SYMBOL(native_get_debugreg);
384NOKPROBE_SYMBOL(native_set_debugreg);
385NOKPROBE_SYMBOL(native_load_idt);
 
386
387#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_PAE)
388/* 32-bit pagetable entries */
389#define PTE_IDENT	__PV_IS_CALLEE_SAVE(_paravirt_ident_32)
390#else
391/* 64-bit pagetable entries */
392#define PTE_IDENT	__PV_IS_CALLEE_SAVE(_paravirt_ident_64)
393#endif
394
395struct pv_mmu_ops pv_mmu_ops __ro_after_init = {
396
397	.read_cr2 = native_read_cr2,
398	.write_cr2 = native_write_cr2,
399	.read_cr3 = __native_read_cr3,
400	.write_cr3 = native_write_cr3,
401
402	.flush_tlb_user = native_flush_tlb,
403	.flush_tlb_kernel = native_flush_tlb_global,
404	.flush_tlb_one_user = native_flush_tlb_one_user,
405	.flush_tlb_others = native_flush_tlb_others,
406
407	.pgd_alloc = __paravirt_pgd_alloc,
408	.pgd_free = paravirt_nop,
409
410	.alloc_pte = paravirt_nop,
411	.alloc_pmd = paravirt_nop,
412	.alloc_pud = paravirt_nop,
413	.alloc_p4d = paravirt_nop,
414	.release_pte = paravirt_nop,
415	.release_pmd = paravirt_nop,
416	.release_pud = paravirt_nop,
417	.release_p4d = paravirt_nop,
418
419	.set_pte = native_set_pte,
420	.set_pte_at = native_set_pte_at,
421	.set_pmd = native_set_pmd,
 
 
 
 
 
422
423	.ptep_modify_prot_start = __ptep_modify_prot_start,
424	.ptep_modify_prot_commit = __ptep_modify_prot_commit,
425
426#if CONFIG_PGTABLE_LEVELS >= 3
427#ifdef CONFIG_X86_PAE
428	.set_pte_atomic = native_set_pte_atomic,
429	.pte_clear = native_pte_clear,
430	.pmd_clear = native_pmd_clear,
431#endif
432	.set_pud = native_set_pud,
433
434	.pmd_val = PTE_IDENT,
435	.make_pmd = PTE_IDENT,
436
437#if CONFIG_PGTABLE_LEVELS >= 4
438	.pud_val = PTE_IDENT,
439	.make_pud = PTE_IDENT,
440
441	.set_p4d = native_set_p4d,
442
443#if CONFIG_PGTABLE_LEVELS >= 5
444	.p4d_val = PTE_IDENT,
445	.make_p4d = PTE_IDENT,
446
447	.set_pgd = native_set_pgd,
448#endif /* CONFIG_PGTABLE_LEVELS >= 5 */
449#endif /* CONFIG_PGTABLE_LEVELS >= 4 */
450#endif /* CONFIG_PGTABLE_LEVELS >= 3 */
451
452	.pte_val = PTE_IDENT,
453	.pgd_val = PTE_IDENT,
454
455	.make_pte = PTE_IDENT,
456	.make_pgd = PTE_IDENT,
457
458	.dup_mmap = paravirt_nop,
459	.exit_mmap = paravirt_nop,
460	.activate_mm = paravirt_nop,
461
462	.lazy_mode = {
463		.enter = paravirt_nop,
464		.leave = paravirt_nop,
465		.flush = paravirt_nop,
466	},
467
468	.set_fixmap = native_set_fixmap,
469};
470
471EXPORT_SYMBOL_GPL(pv_time_ops);
472EXPORT_SYMBOL    (pv_cpu_ops);
473EXPORT_SYMBOL    (pv_mmu_ops);
 
474EXPORT_SYMBOL_GPL(pv_info);
475EXPORT_SYMBOL    (pv_irq_ops);
v3.5.6
  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
 27#include <asm/bug.h>
 28#include <asm/paravirt.h>
 29#include <asm/debugreg.h>
 30#include <asm/desc.h>
 31#include <asm/setup.h>
 32#include <asm/pgtable.h>
 33#include <asm/time.h>
 34#include <asm/pgalloc.h>
 35#include <asm/irq.h>
 36#include <asm/delay.h>
 37#include <asm/fixmap.h>
 38#include <asm/apic.h>
 39#include <asm/tlbflush.h>
 40#include <asm/timer.h>
 41#include <asm/special_insns.h>
 42
 43/* nop stub */
 44void _paravirt_nop(void)
 45{
 46}
 
 
 
 
 
 
 
 
 47
 48/* identity function, which can be inlined */
 49u32 _paravirt_ident_32(u32 x)
 50{
 51	return x;
 52}
 53
 54u64 _paravirt_ident_64(u64 x)
 55{
 56	return x;
 57}
 58
 59void __init default_banner(void)
 60{
 61	printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
 62	       pv_info.name);
 63}
 64
 65/* Simple instruction patching code. */
 66#define DEF_NATIVE(ops, name, code)					\
 67	extern const char start_##ops##_##name[], end_##ops##_##name[];	\
 68	asm("start_" #ops "_" #name ": " code "; end_" #ops "_" #name ":")
 69
 70/* Undefined instruction for dealing with missing ops pointers. */
 71static const unsigned char ud2a[] = { 0x0f, 0x0b };
 72
 73unsigned paravirt_patch_nop(void)
 74{
 75	return 0;
 76}
 77
 78unsigned paravirt_patch_ignore(unsigned len)
 79{
 80	return len;
 81}
 82
 83struct branch {
 84	unsigned char opcode;
 85	u32 delta;
 86} __attribute__((packed));
 87
 88unsigned paravirt_patch_call(void *insnbuf,
 89			     const void *target, u16 tgt_clobbers,
 90			     unsigned long addr, u16 site_clobbers,
 91			     unsigned len)
 92{
 93	struct branch *b = insnbuf;
 94	unsigned long delta = (unsigned long)target - (addr+5);
 95
 96	if (tgt_clobbers & ~site_clobbers)
 97		return len;	/* target would clobber too much for this site */
 98	if (len < 5)
 99		return len;	/* call too long for patch site */
100
101	b->opcode = 0xe8; /* call */
102	b->delta = delta;
103	BUILD_BUG_ON(sizeof(*b) != 5);
104
105	return 5;
106}
107
108unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
109			    unsigned long addr, unsigned len)
110{
111	struct branch *b = insnbuf;
112	unsigned long delta = (unsigned long)target - (addr+5);
113
114	if (len < 5)
115		return len;	/* call too long for patch site */
116
117	b->opcode = 0xe9;	/* jmp */
118	b->delta = delta;
119
120	return 5;
121}
122
123/* Neat trick to map patch type back to the call within the
124 * corresponding structure. */
 
 
 
 
 
 
 
 
 
 
125static void *get_call_destination(u8 type)
126{
127	struct paravirt_patch_template tmpl = {
128		.pv_init_ops = pv_init_ops,
129		.pv_time_ops = pv_time_ops,
130		.pv_cpu_ops = pv_cpu_ops,
131		.pv_irq_ops = pv_irq_ops,
132		.pv_apic_ops = pv_apic_ops,
133		.pv_mmu_ops = pv_mmu_ops,
134#ifdef CONFIG_PARAVIRT_SPINLOCKS
135		.pv_lock_ops = pv_lock_ops,
136#endif
137	};
138	return *((void **)&tmpl + type);
139}
140
141unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
142				unsigned long addr, unsigned len)
143{
144	void *opfunc = get_call_destination(type);
145	unsigned ret;
146
147	if (opfunc == NULL)
148		/* If there's no function, patch it with a ud2a (BUG) */
149		ret = paravirt_patch_insns(insnbuf, len, ud2a, ud2a+sizeof(ud2a));
150	else if (opfunc == _paravirt_nop)
151		/* If the operation is a nop, then nop the callsite */
152		ret = paravirt_patch_nop();
153
154	/* identity functions just return their single argument */
155	else if (opfunc == _paravirt_ident_32)
156		ret = paravirt_patch_ident_32(insnbuf, len);
157	else if (opfunc == _paravirt_ident_64)
158		ret = paravirt_patch_ident_64(insnbuf, len);
159
160	else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
161		 type == PARAVIRT_PATCH(pv_cpu_ops.irq_enable_sysexit) ||
162		 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret32) ||
163		 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret64))
164		/* If operation requires a jmp, then jmp */
165		ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
166	else
167		/* Otherwise call the function; assume target could
168		   clobber any caller-save reg */
169		ret = paravirt_patch_call(insnbuf, opfunc, CLBR_ANY,
170					  addr, clobbers, len);
171
172	return ret;
173}
174
175unsigned paravirt_patch_insns(void *insnbuf, unsigned len,
176			      const char *start, const char *end)
177{
178	unsigned insn_len = end - start;
179
180	if (insn_len > len || start == NULL)
181		insn_len = len;
182	else
183		memcpy(insnbuf, start, insn_len);
184
185	return insn_len;
186}
187
188static void native_flush_tlb(void)
189{
190	__native_flush_tlb();
191}
192
193/*
194 * Global pages have to be flushed a bit differently. Not a real
195 * performance problem because this does not happen often.
196 */
197static void native_flush_tlb_global(void)
198{
199	__native_flush_tlb_global();
200}
201
202static void native_flush_tlb_single(unsigned long addr)
203{
204	__native_flush_tlb_single(addr);
205}
206
207struct static_key paravirt_steal_enabled;
208struct static_key paravirt_steal_rq_enabled;
209
210static u64 native_steal_clock(int cpu)
211{
212	return 0;
213}
214
215/* These are in entry.S */
216extern void native_iret(void);
217extern void native_irq_enable_sysexit(void);
218extern void native_usergs_sysret32(void);
219extern void native_usergs_sysret64(void);
220
221static struct resource reserve_ioports = {
222	.start = 0,
223	.end = IO_SPACE_LIMIT,
224	.name = "paravirt-ioport",
225	.flags = IORESOURCE_IO | IORESOURCE_BUSY,
226};
227
228/*
229 * Reserve the whole legacy IO space to prevent any legacy drivers
230 * from wasting time probing for their hardware.  This is a fairly
231 * brute-force approach to disabling all non-virtual drivers.
232 *
233 * Note that this must be called very early to have any effect.
234 */
235int paravirt_disable_iospace(void)
236{
237	return request_resource(&ioport_resource, &reserve_ioports);
238}
239
240static DEFINE_PER_CPU(enum paravirt_lazy_mode, paravirt_lazy_mode) = PARAVIRT_LAZY_NONE;
241
242static inline void enter_lazy(enum paravirt_lazy_mode mode)
243{
244	BUG_ON(this_cpu_read(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE);
245
246	this_cpu_write(paravirt_lazy_mode, mode);
247}
248
249static void leave_lazy(enum paravirt_lazy_mode mode)
250{
251	BUG_ON(this_cpu_read(paravirt_lazy_mode) != mode);
252
253	this_cpu_write(paravirt_lazy_mode, PARAVIRT_LAZY_NONE);
254}
255
256void paravirt_enter_lazy_mmu(void)
257{
258	enter_lazy(PARAVIRT_LAZY_MMU);
259}
260
261void paravirt_leave_lazy_mmu(void)
262{
263	leave_lazy(PARAVIRT_LAZY_MMU);
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
295void arch_flush_lazy_mmu_mode(void)
296{
297	preempt_disable();
298
299	if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
300		arch_leave_lazy_mmu_mode();
301		arch_enter_lazy_mmu_mode();
302	}
303
304	preempt_enable();
305}
306
307struct pv_info pv_info = {
308	.name = "bare hardware",
309	.paravirt_enabled = 0,
310	.kernel_rpl = 0,
311	.shared_kernel_pmd = 1,	/* Only used when CONFIG_X86_PAE is set */
312
313#ifdef CONFIG_X86_64
314	.extra_user_64bit_cs = __USER_CS,
315#endif
316};
317
318struct pv_init_ops pv_init_ops = {
319	.patch = native_patch,
320};
321
322struct pv_time_ops pv_time_ops = {
323	.sched_clock = native_sched_clock,
324	.steal_clock = native_steal_clock,
325};
326
327struct pv_irq_ops pv_irq_ops = {
328	.save_fl = __PV_IS_CALLEE_SAVE(native_save_fl),
329	.restore_fl = __PV_IS_CALLEE_SAVE(native_restore_fl),
330	.irq_disable = __PV_IS_CALLEE_SAVE(native_irq_disable),
331	.irq_enable = __PV_IS_CALLEE_SAVE(native_irq_enable),
332	.safe_halt = native_safe_halt,
333	.halt = native_halt,
334#ifdef CONFIG_X86_64
335	.adjust_exception_frame = paravirt_nop,
336#endif
337};
338
339struct pv_cpu_ops pv_cpu_ops = {
340	.cpuid = native_cpuid,
341	.get_debugreg = native_get_debugreg,
342	.set_debugreg = native_set_debugreg,
343	.clts = native_clts,
344	.read_cr0 = native_read_cr0,
345	.write_cr0 = native_write_cr0,
346	.read_cr4 = native_read_cr4,
347	.read_cr4_safe = native_read_cr4_safe,
348	.write_cr4 = native_write_cr4,
349#ifdef CONFIG_X86_64
350	.read_cr8 = native_read_cr8,
351	.write_cr8 = native_write_cr8,
352#endif
353	.wbinvd = native_wbinvd,
354	.read_msr = native_read_msr_safe,
355	.rdmsr_regs = native_rdmsr_safe_regs,
356	.write_msr = native_write_msr_safe,
357	.wrmsr_regs = native_wrmsr_safe_regs,
358	.read_tsc = native_read_tsc,
359	.read_pmc = native_read_pmc,
360	.read_tscp = native_read_tscp,
361	.load_tr_desc = native_load_tr_desc,
362	.set_ldt = native_set_ldt,
363	.load_gdt = native_load_gdt,
364	.load_idt = native_load_idt,
365	.store_gdt = native_store_gdt,
366	.store_idt = native_store_idt,
367	.store_tr = native_store_tr,
368	.load_tls = native_load_tls,
369#ifdef CONFIG_X86_64
370	.load_gs_index = native_load_gs_index,
371#endif
372	.write_ldt_entry = native_write_ldt_entry,
373	.write_gdt_entry = native_write_gdt_entry,
374	.write_idt_entry = native_write_idt_entry,
375
376	.alloc_ldt = paravirt_nop,
377	.free_ldt = paravirt_nop,
378
379	.load_sp0 = native_load_sp0,
380
381#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
382	.irq_enable_sysexit = native_irq_enable_sysexit,
383#endif
384#ifdef CONFIG_X86_64
385#ifdef CONFIG_IA32_EMULATION
386	.usergs_sysret32 = native_usergs_sysret32,
387#endif
388	.usergs_sysret64 = native_usergs_sysret64,
389#endif
390	.iret = native_iret,
391	.swapgs = native_swapgs,
392
393	.set_iopl_mask = native_set_iopl_mask,
394	.io_delay = native_io_delay,
395
396	.start_context_switch = paravirt_nop,
397	.end_context_switch = paravirt_nop,
398};
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/* 32-bit pagetable entries */
408#define PTE_IDENT	__PV_IS_CALLEE_SAVE(_paravirt_ident_32)
409#else
410/* 64-bit pagetable entries */
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 PAGETABLE_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 PAGETABLE_LEVELS == 4
460	.pud_val = PTE_IDENT,
461	.make_pud = PTE_IDENT,
462
 
 
 
 
 
 
463	.set_pgd = native_set_pgd,
464#endif
465#endif /* PAGETABLE_LEVELS >= 3 */
 
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	},
481
482	.set_fixmap = native_set_fixmap,
483};
484
485EXPORT_SYMBOL_GPL(pv_time_ops);
486EXPORT_SYMBOL    (pv_cpu_ops);
487EXPORT_SYMBOL    (pv_mmu_ops);
488EXPORT_SYMBOL_GPL(pv_apic_ops);
489EXPORT_SYMBOL_GPL(pv_info);
490EXPORT_SYMBOL    (pv_irq_ops);