1 /* Paravirtualization interfaces
2 Copyright (C) 2006 Rusty Russell IBM Corporation
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.
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.
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
18 2007 - x86_64 support added by Glauber de Oliveira Costa, Red Hat Inc
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>
28 #include <asm/paravirt.h>
30 #include <asm/setup.h>
31 #include <asm/arch_hooks.h>
34 #include <asm/delay.h>
35 #include <asm/fixmap.h>
37 #include <asm/tlbflush.h>
38 #include <asm/timer.h>
41 void _paravirt_nop(void)
45 static void __init
default_banner(void)
47 printk(KERN_INFO
"Booting paravirtualized kernel on %s\n",
51 char *memory_setup(void)
53 return pv_init_ops
.memory_setup();
56 /* Simple instruction patching code. */
57 #define DEF_NATIVE(ops, name, code) \
58 extern const char start_##ops##_##name[], end_##ops##_##name[]; \
59 asm("start_" #ops "_" #name ": " code "; end_" #ops "_" #name ":")
61 DEF_NATIVE(pv_irq_ops
, irq_disable
, "cli");
62 DEF_NATIVE(pv_irq_ops
, irq_enable
, "sti");
63 DEF_NATIVE(pv_irq_ops
, restore_fl
, "push %eax; popf");
64 DEF_NATIVE(pv_irq_ops
, save_fl
, "pushf; pop %eax");
65 DEF_NATIVE(pv_cpu_ops
, iret
, "iret");
66 DEF_NATIVE(pv_cpu_ops
, irq_enable_syscall_ret
, "sti; sysexit");
67 DEF_NATIVE(pv_mmu_ops
, read_cr2
, "mov %cr2, %eax");
68 DEF_NATIVE(pv_mmu_ops
, write_cr3
, "mov %eax, %cr3");
69 DEF_NATIVE(pv_mmu_ops
, read_cr3
, "mov %cr3, %eax");
70 DEF_NATIVE(pv_cpu_ops
, clts
, "clts");
71 DEF_NATIVE(pv_cpu_ops
, read_tsc
, "rdtsc");
73 /* Undefined instruction for dealing with missing ops pointers. */
74 static const unsigned char ud2a
[] = { 0x0f, 0x0b };
76 static unsigned native_patch(u8 type
, u16 clobbers
, void *ibuf
,
77 unsigned long addr
, unsigned len
)
79 const unsigned char *start
, *end
;
83 #define SITE(ops, x) \
84 case PARAVIRT_PATCH(ops.x): \
85 start = start_##ops##_##x; \
86 end = end_##ops##_##x; \
89 SITE(pv_irq_ops
, irq_disable
);
90 SITE(pv_irq_ops
, irq_enable
);
91 SITE(pv_irq_ops
, restore_fl
);
92 SITE(pv_irq_ops
, save_fl
);
93 SITE(pv_cpu_ops
, iret
);
94 SITE(pv_cpu_ops
, irq_enable_syscall_ret
);
95 SITE(pv_mmu_ops
, read_cr2
);
96 SITE(pv_mmu_ops
, read_cr3
);
97 SITE(pv_mmu_ops
, write_cr3
);
98 SITE(pv_cpu_ops
, clts
);
99 SITE(pv_cpu_ops
, read_tsc
);
103 ret
= paravirt_patch_insns(ibuf
, len
, start
, end
);
107 ret
= paravirt_patch_default(type
, clobbers
, ibuf
, addr
, len
);
114 unsigned paravirt_patch_nop(void)
119 unsigned paravirt_patch_ignore(unsigned len
)
125 unsigned char opcode
;
127 } __attribute__((packed
));
129 unsigned paravirt_patch_call(void *insnbuf
,
130 const void *target
, u16 tgt_clobbers
,
131 unsigned long addr
, u16 site_clobbers
,
134 struct branch
*b
= insnbuf
;
135 unsigned long delta
= (unsigned long)target
- (addr
+5);
137 if (tgt_clobbers
& ~site_clobbers
)
138 return len
; /* target would clobber too much for this site */
140 return len
; /* call too long for patch site */
142 b
->opcode
= 0xe8; /* call */
144 BUILD_BUG_ON(sizeof(*b
) != 5);
149 unsigned paravirt_patch_jmp(void *insnbuf
, const void *target
,
150 unsigned long addr
, unsigned len
)
152 struct branch
*b
= insnbuf
;
153 unsigned long delta
= (unsigned long)target
- (addr
+5);
156 return len
; /* call too long for patch site */
158 b
->opcode
= 0xe9; /* jmp */
164 /* Neat trick to map patch type back to the call within the
165 * corresponding structure. */
166 static void *get_call_destination(u8 type
)
168 struct paravirt_patch_template tmpl
= {
169 .pv_init_ops
= pv_init_ops
,
170 .pv_time_ops
= pv_time_ops
,
171 .pv_cpu_ops
= pv_cpu_ops
,
172 .pv_irq_ops
= pv_irq_ops
,
173 .pv_apic_ops
= pv_apic_ops
,
174 .pv_mmu_ops
= pv_mmu_ops
,
176 return *((void **)&tmpl
+ type
);
179 unsigned paravirt_patch_default(u8 type
, u16 clobbers
, void *insnbuf
,
180 unsigned long addr
, unsigned len
)
182 void *opfunc
= get_call_destination(type
);
186 /* If there's no function, patch it with a ud2a (BUG) */
187 ret
= paravirt_patch_insns(insnbuf
, len
, ud2a
, ud2a
+sizeof(ud2a
));
188 else if (opfunc
== paravirt_nop
)
189 /* If the operation is a nop, then nop the callsite */
190 ret
= paravirt_patch_nop();
191 else if (type
== PARAVIRT_PATCH(pv_cpu_ops
.iret
) ||
192 type
== PARAVIRT_PATCH(pv_cpu_ops
.irq_enable_syscall_ret
))
193 /* If operation requires a jmp, then jmp */
194 ret
= paravirt_patch_jmp(insnbuf
, opfunc
, addr
, len
);
196 /* Otherwise call the function; assume target could
197 clobber any caller-save reg */
198 ret
= paravirt_patch_call(insnbuf
, opfunc
, CLBR_ANY
,
199 addr
, clobbers
, len
);
204 unsigned paravirt_patch_insns(void *insnbuf
, unsigned len
,
205 const char *start
, const char *end
)
207 unsigned insn_len
= end
- start
;
209 if (insn_len
> len
|| start
== NULL
)
212 memcpy(insnbuf
, start
, insn_len
);
219 pv_irq_ops
.init_IRQ();
222 static void native_flush_tlb(void)
224 __native_flush_tlb();
228 * Global pages have to be flushed a bit differently. Not a real
229 * performance problem because this does not happen often.
231 static void native_flush_tlb_global(void)
233 __native_flush_tlb_global();
236 static void native_flush_tlb_single(unsigned long addr
)
238 __native_flush_tlb_single(addr
);
241 /* These are in entry.S */
242 extern void native_iret(void);
243 extern void native_irq_enable_syscall_ret(void);
245 static int __init
print_banner(void)
247 pv_init_ops
.banner();
250 core_initcall(print_banner
);
252 static struct resource reserve_ioports
= {
254 .end
= IO_SPACE_LIMIT
,
255 .name
= "paravirt-ioport",
256 .flags
= IORESOURCE_IO
| IORESOURCE_BUSY
,
259 static struct resource reserve_iomem
= {
262 .name
= "paravirt-iomem",
263 .flags
= IORESOURCE_MEM
| IORESOURCE_BUSY
,
267 * Reserve the whole legacy IO space to prevent any legacy drivers
268 * from wasting time probing for their hardware. This is a fairly
269 * brute-force approach to disabling all non-virtual drivers.
271 * Note that this must be called very early to have any effect.
273 int paravirt_disable_iospace(void)
277 ret
= request_resource(&ioport_resource
, &reserve_ioports
);
279 ret
= request_resource(&iomem_resource
, &reserve_iomem
);
281 release_resource(&reserve_ioports
);
287 static DEFINE_PER_CPU(enum paravirt_lazy_mode
, paravirt_lazy_mode
) = PARAVIRT_LAZY_NONE
;
289 static inline void enter_lazy(enum paravirt_lazy_mode mode
)
291 BUG_ON(x86_read_percpu(paravirt_lazy_mode
) != PARAVIRT_LAZY_NONE
);
292 BUG_ON(preemptible());
294 x86_write_percpu(paravirt_lazy_mode
, mode
);
297 void paravirt_leave_lazy(enum paravirt_lazy_mode mode
)
299 BUG_ON(x86_read_percpu(paravirt_lazy_mode
) != mode
);
300 BUG_ON(preemptible());
302 x86_write_percpu(paravirt_lazy_mode
, PARAVIRT_LAZY_NONE
);
305 void paravirt_enter_lazy_mmu(void)
307 enter_lazy(PARAVIRT_LAZY_MMU
);
310 void paravirt_leave_lazy_mmu(void)
312 paravirt_leave_lazy(PARAVIRT_LAZY_MMU
);
315 void paravirt_enter_lazy_cpu(void)
317 enter_lazy(PARAVIRT_LAZY_CPU
);
320 void paravirt_leave_lazy_cpu(void)
322 paravirt_leave_lazy(PARAVIRT_LAZY_CPU
);
325 enum paravirt_lazy_mode
paravirt_get_lazy_mode(void)
327 return x86_read_percpu(paravirt_lazy_mode
);
330 struct pv_info pv_info
= {
331 .name
= "bare hardware",
332 .paravirt_enabled
= 0,
334 .shared_kernel_pmd
= 1, /* Only used when CONFIG_X86_PAE is set */
337 struct pv_init_ops pv_init_ops
= {
338 .patch
= native_patch
,
339 .banner
= default_banner
,
340 .arch_setup
= paravirt_nop
,
341 .memory_setup
= machine_specific_memory_setup
,
344 struct pv_time_ops pv_time_ops
= {
345 .time_init
= hpet_time_init
,
346 .get_wallclock
= native_get_wallclock
,
347 .set_wallclock
= native_set_wallclock
,
348 .sched_clock
= native_sched_clock
,
349 .get_cpu_khz
= native_calculate_cpu_khz
,
352 struct pv_irq_ops pv_irq_ops
= {
353 .init_IRQ
= native_init_IRQ
,
354 .save_fl
= native_save_fl
,
355 .restore_fl
= native_restore_fl
,
356 .irq_disable
= native_irq_disable
,
357 .irq_enable
= native_irq_enable
,
358 .safe_halt
= native_safe_halt
,
362 struct pv_cpu_ops pv_cpu_ops
= {
363 .cpuid
= native_cpuid
,
364 .get_debugreg
= native_get_debugreg
,
365 .set_debugreg
= native_set_debugreg
,
367 .read_cr0
= native_read_cr0
,
368 .write_cr0
= native_write_cr0
,
369 .read_cr4
= native_read_cr4
,
370 .read_cr4_safe
= native_read_cr4_safe
,
371 .write_cr4
= native_write_cr4
,
372 .wbinvd
= native_wbinvd
,
373 .read_msr
= native_read_msr_safe
,
374 .write_msr
= native_write_msr_safe
,
375 .read_tsc
= native_read_tsc
,
376 .read_pmc
= native_read_pmc
,
377 .read_tscp
= native_read_tscp
,
378 .load_tr_desc
= native_load_tr_desc
,
379 .set_ldt
= native_set_ldt
,
380 .load_gdt
= native_load_gdt
,
381 .load_idt
= native_load_idt
,
382 .store_gdt
= native_store_gdt
,
383 .store_idt
= native_store_idt
,
384 .store_tr
= native_store_tr
,
385 .load_tls
= native_load_tls
,
386 .write_ldt_entry
= native_write_ldt_entry
,
387 .write_gdt_entry
= native_write_gdt_entry
,
388 .write_idt_entry
= native_write_idt_entry
,
389 .load_sp0
= native_load_sp0
,
391 .irq_enable_syscall_ret
= native_irq_enable_syscall_ret
,
394 .set_iopl_mask
= native_set_iopl_mask
,
395 .io_delay
= native_io_delay
,
398 .enter
= paravirt_nop
,
399 .leave
= paravirt_nop
,
403 struct pv_apic_ops pv_apic_ops
= {
404 #ifdef CONFIG_X86_LOCAL_APIC
405 .apic_write
= native_apic_write
,
406 .apic_write_atomic
= native_apic_write_atomic
,
407 .apic_read
= native_apic_read
,
408 .setup_boot_clock
= setup_boot_APIC_clock
,
409 .setup_secondary_clock
= setup_secondary_APIC_clock
,
410 .startup_ipi_hook
= paravirt_nop
,
414 struct pv_mmu_ops pv_mmu_ops
= {
415 .pagetable_setup_start
= native_pagetable_setup_start
,
416 .pagetable_setup_done
= native_pagetable_setup_done
,
418 .read_cr2
= native_read_cr2
,
419 .write_cr2
= native_write_cr2
,
420 .read_cr3
= native_read_cr3
,
421 .write_cr3
= native_write_cr3
,
423 .flush_tlb_user
= native_flush_tlb
,
424 .flush_tlb_kernel
= native_flush_tlb_global
,
425 .flush_tlb_single
= native_flush_tlb_single
,
426 .flush_tlb_others
= native_flush_tlb_others
,
428 .alloc_pt
= paravirt_nop
,
429 .alloc_pd
= paravirt_nop
,
430 .alloc_pd_clone
= paravirt_nop
,
431 .release_pt
= paravirt_nop
,
432 .release_pd
= paravirt_nop
,
434 .set_pte
= native_set_pte
,
435 .set_pte_at
= native_set_pte_at
,
436 .set_pmd
= native_set_pmd
,
437 .pte_update
= paravirt_nop
,
438 .pte_update_defer
= paravirt_nop
,
440 #ifdef CONFIG_HIGHPTE
441 .kmap_atomic_pte
= kmap_atomic
,
444 #ifdef CONFIG_X86_PAE
445 .set_pte_atomic
= native_set_pte_atomic
,
446 .set_pte_present
= native_set_pte_present
,
447 .set_pud
= native_set_pud
,
448 .pte_clear
= native_pte_clear
,
449 .pmd_clear
= native_pmd_clear
,
451 .pmd_val
= native_pmd_val
,
452 .make_pmd
= native_make_pmd
,
455 .pte_val
= native_pte_val
,
456 .pgd_val
= native_pgd_val
,
458 .make_pte
= native_make_pte
,
459 .make_pgd
= native_make_pgd
,
461 .dup_mmap
= paravirt_nop
,
462 .exit_mmap
= paravirt_nop
,
463 .activate_mm
= paravirt_nop
,
466 .enter
= paravirt_nop
,
467 .leave
= paravirt_nop
,
471 EXPORT_SYMBOL_GPL(pv_time_ops
);
472 EXPORT_SYMBOL (pv_cpu_ops
);
473 EXPORT_SYMBOL (pv_mmu_ops
);
474 EXPORT_SYMBOL_GPL(pv_apic_ops
);
475 EXPORT_SYMBOL_GPL(pv_info
);
476 EXPORT_SYMBOL (pv_irq_ops
);