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 #include <linux/errno.h>
19 #include <linux/module.h>
20 #include <linux/efi.h>
21 #include <linux/bcd.h>
22 #include <linux/highmem.h>
25 #include <asm/paravirt.h>
27 #include <asm/setup.h>
28 #include <asm/arch_hooks.h>
31 #include <asm/delay.h>
32 #include <asm/fixmap.h>
34 #include <asm/tlbflush.h>
35 #include <asm/timer.h>
38 void _paravirt_nop(void)
42 static void __init
default_banner(void)
44 printk(KERN_INFO
"Booting paravirtualized kernel on %s\n",
48 char *memory_setup(void)
50 return pv_init_ops
.memory_setup();
53 /* Simple instruction patching code. */
54 #define DEF_NATIVE(ops, name, code) \
55 extern const char start_##ops##_##name[], end_##ops##_##name[]; \
56 asm("start_" #ops "_" #name ": " code "; end_" #ops "_" #name ":")
58 DEF_NATIVE(pv_irq_ops
, irq_disable
, "cli");
59 DEF_NATIVE(pv_irq_ops
, irq_enable
, "sti");
60 DEF_NATIVE(pv_irq_ops
, restore_fl
, "push %eax; popf");
61 DEF_NATIVE(pv_irq_ops
, save_fl
, "pushf; pop %eax");
62 DEF_NATIVE(pv_cpu_ops
, iret
, "iret");
63 DEF_NATIVE(pv_cpu_ops
, irq_enable_sysexit
, "sti; sysexit");
64 DEF_NATIVE(pv_mmu_ops
, read_cr2
, "mov %cr2, %eax");
65 DEF_NATIVE(pv_mmu_ops
, write_cr3
, "mov %eax, %cr3");
66 DEF_NATIVE(pv_mmu_ops
, read_cr3
, "mov %cr3, %eax");
67 DEF_NATIVE(pv_cpu_ops
, clts
, "clts");
68 DEF_NATIVE(pv_cpu_ops
, read_tsc
, "rdtsc");
70 /* Undefined instruction for dealing with missing ops pointers. */
71 static const unsigned char ud2a
[] = { 0x0f, 0x0b };
73 static unsigned native_patch(u8 type
, u16 clobbers
, void *ibuf
,
74 unsigned long addr
, unsigned len
)
76 const unsigned char *start
, *end
;
80 #define SITE(ops, x) \
81 case PARAVIRT_PATCH(ops.x): \
82 start = start_##ops##_##x; \
83 end = end_##ops##_##x; \
86 SITE(pv_irq_ops
, irq_disable
);
87 SITE(pv_irq_ops
, irq_enable
);
88 SITE(pv_irq_ops
, restore_fl
);
89 SITE(pv_irq_ops
, save_fl
);
90 SITE(pv_cpu_ops
, iret
);
91 SITE(pv_cpu_ops
, irq_enable_sysexit
);
92 SITE(pv_mmu_ops
, read_cr2
);
93 SITE(pv_mmu_ops
, read_cr3
);
94 SITE(pv_mmu_ops
, write_cr3
);
95 SITE(pv_cpu_ops
, clts
);
96 SITE(pv_cpu_ops
, read_tsc
);
100 ret
= paravirt_patch_insns(ibuf
, len
, start
, end
);
104 ret
= paravirt_patch_default(type
, clobbers
, ibuf
, addr
, len
);
111 unsigned paravirt_patch_nop(void)
116 unsigned paravirt_patch_ignore(unsigned len
)
122 unsigned char opcode
;
124 } __attribute__((packed
));
126 unsigned paravirt_patch_call(void *insnbuf
,
127 const void *target
, u16 tgt_clobbers
,
128 unsigned long addr
, u16 site_clobbers
,
131 struct branch
*b
= insnbuf
;
132 unsigned long delta
= (unsigned long)target
- (addr
+5);
134 if (tgt_clobbers
& ~site_clobbers
)
135 return len
; /* target would clobber too much for this site */
137 return len
; /* call too long for patch site */
139 b
->opcode
= 0xe8; /* call */
141 BUILD_BUG_ON(sizeof(*b
) != 5);
146 unsigned paravirt_patch_jmp(void *insnbuf
, const void *target
,
147 unsigned long addr
, unsigned len
)
149 struct branch
*b
= insnbuf
;
150 unsigned long delta
= (unsigned long)target
- (addr
+5);
153 return len
; /* call too long for patch site */
155 b
->opcode
= 0xe9; /* jmp */
161 /* Neat trick to map patch type back to the call within the
162 * corresponding structure. */
163 static void *get_call_destination(u8 type
)
165 struct paravirt_patch_template tmpl
= {
166 .pv_init_ops
= pv_init_ops
,
167 .pv_time_ops
= pv_time_ops
,
168 .pv_cpu_ops
= pv_cpu_ops
,
169 .pv_irq_ops
= pv_irq_ops
,
170 .pv_apic_ops
= pv_apic_ops
,
171 .pv_mmu_ops
= pv_mmu_ops
,
173 return *((void **)&tmpl
+ type
);
176 unsigned paravirt_patch_default(u8 type
, u16 clobbers
, void *insnbuf
,
177 unsigned long addr
, unsigned len
)
179 void *opfunc
= get_call_destination(type
);
183 /* If there's no function, patch it with a ud2a (BUG) */
184 ret
= paravirt_patch_insns(insnbuf
, len
, ud2a
, ud2a
+sizeof(ud2a
));
185 else if (opfunc
== paravirt_nop
)
186 /* If the operation is a nop, then nop the callsite */
187 ret
= paravirt_patch_nop();
188 else if (type
== PARAVIRT_PATCH(pv_cpu_ops
.iret
) ||
189 type
== PARAVIRT_PATCH(pv_cpu_ops
.irq_enable_sysexit
))
190 /* If operation requires a jmp, then jmp */
191 ret
= paravirt_patch_jmp(insnbuf
, opfunc
, addr
, len
);
193 /* Otherwise call the function; assume target could
194 clobber any caller-save reg */
195 ret
= paravirt_patch_call(insnbuf
, opfunc
, CLBR_ANY
,
196 addr
, clobbers
, len
);
201 unsigned paravirt_patch_insns(void *insnbuf
, unsigned len
,
202 const char *start
, const char *end
)
204 unsigned insn_len
= end
- start
;
206 if (insn_len
> len
|| start
== NULL
)
209 memcpy(insnbuf
, start
, insn_len
);
216 pv_irq_ops
.init_IRQ();
219 static void native_flush_tlb(void)
221 __native_flush_tlb();
225 * Global pages have to be flushed a bit differently. Not a real
226 * performance problem because this does not happen often.
228 static void native_flush_tlb_global(void)
230 __native_flush_tlb_global();
233 static void native_flush_tlb_single(unsigned long addr
)
235 __native_flush_tlb_single(addr
);
238 /* These are in entry.S */
239 extern void native_iret(void);
240 extern void native_irq_enable_sysexit(void);
242 static int __init
print_banner(void)
244 pv_init_ops
.banner();
247 core_initcall(print_banner
);
249 static struct resource reserve_ioports
= {
251 .end
= IO_SPACE_LIMIT
,
252 .name
= "paravirt-ioport",
253 .flags
= IORESOURCE_IO
| IORESOURCE_BUSY
,
256 static struct resource reserve_iomem
= {
259 .name
= "paravirt-iomem",
260 .flags
= IORESOURCE_MEM
| IORESOURCE_BUSY
,
264 * Reserve the whole legacy IO space to prevent any legacy drivers
265 * from wasting time probing for their hardware. This is a fairly
266 * brute-force approach to disabling all non-virtual drivers.
268 * Note that this must be called very early to have any effect.
270 int paravirt_disable_iospace(void)
274 ret
= request_resource(&ioport_resource
, &reserve_ioports
);
276 ret
= request_resource(&iomem_resource
, &reserve_iomem
);
278 release_resource(&reserve_ioports
);
284 static DEFINE_PER_CPU(enum paravirt_lazy_mode
, paravirt_lazy_mode
) = PARAVIRT_LAZY_NONE
;
286 static inline void enter_lazy(enum paravirt_lazy_mode mode
)
288 BUG_ON(x86_read_percpu(paravirt_lazy_mode
) != PARAVIRT_LAZY_NONE
);
289 BUG_ON(preemptible());
291 x86_write_percpu(paravirt_lazy_mode
, mode
);
294 void paravirt_leave_lazy(enum paravirt_lazy_mode mode
)
296 BUG_ON(x86_read_percpu(paravirt_lazy_mode
) != mode
);
297 BUG_ON(preemptible());
299 x86_write_percpu(paravirt_lazy_mode
, PARAVIRT_LAZY_NONE
);
302 void paravirt_enter_lazy_mmu(void)
304 enter_lazy(PARAVIRT_LAZY_MMU
);
307 void paravirt_leave_lazy_mmu(void)
309 paravirt_leave_lazy(PARAVIRT_LAZY_MMU
);
312 void paravirt_enter_lazy_cpu(void)
314 enter_lazy(PARAVIRT_LAZY_CPU
);
317 void paravirt_leave_lazy_cpu(void)
319 paravirt_leave_lazy(PARAVIRT_LAZY_CPU
);
322 enum paravirt_lazy_mode
paravirt_get_lazy_mode(void)
324 return x86_read_percpu(paravirt_lazy_mode
);
327 struct pv_info pv_info
= {
328 .name
= "bare hardware",
329 .paravirt_enabled
= 0,
331 .shared_kernel_pmd
= 1, /* Only used when CONFIG_X86_PAE is set */
334 struct pv_init_ops pv_init_ops
= {
335 .patch
= native_patch
,
336 .banner
= default_banner
,
337 .arch_setup
= paravirt_nop
,
338 .memory_setup
= machine_specific_memory_setup
,
341 struct pv_time_ops pv_time_ops
= {
342 .time_init
= hpet_time_init
,
343 .get_wallclock
= native_get_wallclock
,
344 .set_wallclock
= native_set_wallclock
,
345 .sched_clock
= native_sched_clock
,
346 .get_cpu_khz
= native_calculate_cpu_khz
,
349 struct pv_irq_ops pv_irq_ops
= {
350 .init_IRQ
= native_init_IRQ
,
351 .save_fl
= native_save_fl
,
352 .restore_fl
= native_restore_fl
,
353 .irq_disable
= native_irq_disable
,
354 .irq_enable
= native_irq_enable
,
355 .safe_halt
= native_safe_halt
,
359 struct pv_cpu_ops pv_cpu_ops
= {
360 .cpuid
= native_cpuid
,
361 .get_debugreg
= native_get_debugreg
,
362 .set_debugreg
= native_set_debugreg
,
364 .read_cr0
= native_read_cr0
,
365 .write_cr0
= native_write_cr0
,
366 .read_cr4
= native_read_cr4
,
367 .read_cr4_safe
= native_read_cr4_safe
,
368 .write_cr4
= native_write_cr4
,
369 .wbinvd
= native_wbinvd
,
370 .read_msr
= native_read_msr_safe
,
371 .write_msr
= native_write_msr_safe
,
372 .read_tsc
= native_read_tsc
,
373 .read_pmc
= native_read_pmc
,
374 .load_tr_desc
= native_load_tr_desc
,
375 .set_ldt
= native_set_ldt
,
376 .load_gdt
= native_load_gdt
,
377 .load_idt
= native_load_idt
,
378 .store_gdt
= native_store_gdt
,
379 .store_idt
= native_store_idt
,
380 .store_tr
= native_store_tr
,
381 .load_tls
= native_load_tls
,
382 .write_ldt_entry
= write_dt_entry
,
383 .write_gdt_entry
= write_dt_entry
,
384 .write_idt_entry
= write_dt_entry
,
385 .load_esp0
= native_load_esp0
,
387 .irq_enable_sysexit
= native_irq_enable_sysexit
,
390 .set_iopl_mask
= native_set_iopl_mask
,
391 .io_delay
= native_io_delay
,
394 .enter
= paravirt_nop
,
395 .leave
= paravirt_nop
,
399 struct pv_apic_ops pv_apic_ops
= {
400 #ifdef CONFIG_X86_LOCAL_APIC
401 .apic_write
= native_apic_write
,
402 .apic_write_atomic
= native_apic_write_atomic
,
403 .apic_read
= native_apic_read
,
404 .setup_boot_clock
= setup_boot_APIC_clock
,
405 .setup_secondary_clock
= setup_secondary_APIC_clock
,
406 .startup_ipi_hook
= paravirt_nop
,
410 struct pv_mmu_ops pv_mmu_ops
= {
411 .pagetable_setup_start
= native_pagetable_setup_start
,
412 .pagetable_setup_done
= native_pagetable_setup_done
,
414 .read_cr2
= native_read_cr2
,
415 .write_cr2
= native_write_cr2
,
416 .read_cr3
= native_read_cr3
,
417 .write_cr3
= native_write_cr3
,
419 .flush_tlb_user
= native_flush_tlb
,
420 .flush_tlb_kernel
= native_flush_tlb_global
,
421 .flush_tlb_single
= native_flush_tlb_single
,
422 .flush_tlb_others
= native_flush_tlb_others
,
424 .alloc_pt
= paravirt_nop
,
425 .alloc_pd
= paravirt_nop
,
426 .alloc_pd_clone
= paravirt_nop
,
427 .release_pt
= paravirt_nop
,
428 .release_pd
= paravirt_nop
,
430 .set_pte
= native_set_pte
,
431 .set_pte_at
= native_set_pte_at
,
432 .set_pmd
= native_set_pmd
,
433 .pte_update
= paravirt_nop
,
434 .pte_update_defer
= paravirt_nop
,
436 #ifdef CONFIG_HIGHPTE
437 .kmap_atomic_pte
= kmap_atomic
,
440 #ifdef CONFIG_X86_PAE
441 .set_pte_atomic
= native_set_pte_atomic
,
442 .set_pte_present
= native_set_pte_present
,
443 .set_pud
= native_set_pud
,
444 .pte_clear
= native_pte_clear
,
445 .pmd_clear
= native_pmd_clear
,
447 .pmd_val
= native_pmd_val
,
448 .make_pmd
= native_make_pmd
,
451 .pte_val
= native_pte_val
,
452 .pgd_val
= native_pgd_val
,
454 .make_pte
= native_make_pte
,
455 .make_pgd
= native_make_pgd
,
457 .dup_mmap
= paravirt_nop
,
458 .exit_mmap
= paravirt_nop
,
459 .activate_mm
= paravirt_nop
,
462 .enter
= paravirt_nop
,
463 .leave
= paravirt_nop
,
467 EXPORT_SYMBOL_GPL(pv_time_ops
);
468 EXPORT_SYMBOL_GPL(pv_cpu_ops
);
469 EXPORT_SYMBOL_GPL(pv_mmu_ops
);
470 EXPORT_SYMBOL_GPL(pv_apic_ops
);
471 EXPORT_SYMBOL_GPL(pv_info
);
472 EXPORT_SYMBOL (pv_irq_ops
);