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 paravirt_ops
.memory_setup();
53 /* Simple instruction patching code. */
54 #define DEF_NATIVE(name, code) \
55 extern const char start_##name[], end_##name[]; \
56 asm("start_" #name ": " code "; end_" #name ":")
58 DEF_NATIVE(irq_disable
, "cli");
59 DEF_NATIVE(irq_enable
, "sti");
60 DEF_NATIVE(restore_fl
, "push %eax; popf");
61 DEF_NATIVE(save_fl
, "pushf; pop %eax");
62 DEF_NATIVE(iret
, "iret");
63 DEF_NATIVE(irq_enable_sysexit
, "sti; sysexit");
64 DEF_NATIVE(read_cr2
, "mov %cr2, %eax");
65 DEF_NATIVE(write_cr3
, "mov %eax, %cr3");
66 DEF_NATIVE(read_cr3
, "mov %cr3, %eax");
67 DEF_NATIVE(clts
, "clts");
68 DEF_NATIVE(read_tsc
, "rdtsc");
70 DEF_NATIVE(ud2a
, "ud2a");
72 static unsigned native_patch(u8 type
, u16 clobbers
, void *insns
, unsigned len
)
74 const unsigned char *start
, *end
;
78 #define SITE(x) case PARAVIRT_PATCH(x): start = start_##x; end = end_##x; goto patch_site
84 SITE(irq_enable_sysexit
);
93 ret
= paravirt_patch_insns(insns
, len
, start
, end
);
96 case PARAVIRT_PATCH(make_pgd
):
97 case PARAVIRT_PATCH(make_pte
):
98 case PARAVIRT_PATCH(pgd_val
):
99 case PARAVIRT_PATCH(pte_val
):
100 #ifdef CONFIG_X86_PAE
101 case PARAVIRT_PATCH(make_pmd
):
102 case PARAVIRT_PATCH(pmd_val
):
104 /* These functions end up returning exactly what
105 they're passed, in the same registers. */
106 ret
= paravirt_patch_nop();
110 ret
= paravirt_patch_default(type
, clobbers
, insns
, len
);
117 unsigned paravirt_patch_nop(void)
122 unsigned paravirt_patch_ignore(unsigned len
)
128 unsigned char opcode
;
130 } __attribute__((packed
));
132 unsigned paravirt_patch_call(void *target
, u16 tgt_clobbers
,
133 void *site
, u16 site_clobbers
,
136 unsigned char *call
= site
;
137 unsigned long delta
= (unsigned long)target
- (unsigned long)(call
+5);
140 if (tgt_clobbers
& ~site_clobbers
)
141 return len
; /* target would clobber too much for this site */
143 return len
; /* call too long for patch site */
145 b
.opcode
= 0xe8; /* call */
147 BUILD_BUG_ON(sizeof(b
) != 5);
148 text_poke(call
, (unsigned char *)&b
, 5);
153 unsigned paravirt_patch_jmp(void *target
, void *site
, unsigned len
)
155 unsigned char *jmp
= site
;
156 unsigned long delta
= (unsigned long)target
- (unsigned long)(jmp
+5);
159 return len
; /* call too long for patch site */
161 b
.opcode
= 0xe9; /* jmp */
163 text_poke(call
, (unsigned char *)&b
, 5);
168 unsigned paravirt_patch_default(u8 type
, u16 clobbers
, void *site
, unsigned len
)
170 void *opfunc
= *((void **)¶virt_ops
+ type
);
174 /* If there's no function, patch it with a ud2a (BUG) */
175 ret
= paravirt_patch_insns(site
, len
, start_ud2a
, end_ud2a
);
176 else if (opfunc
== paravirt_nop
)
177 /* If the operation is a nop, then nop the callsite */
178 ret
= paravirt_patch_nop();
179 else if (type
== PARAVIRT_PATCH(iret
) ||
180 type
== PARAVIRT_PATCH(irq_enable_sysexit
))
181 /* If operation requires a jmp, then jmp */
182 ret
= paravirt_patch_jmp(opfunc
, site
, len
);
184 /* Otherwise call the function; assume target could
185 clobber any caller-save reg */
186 ret
= paravirt_patch_call(opfunc
, CLBR_ANY
,
187 site
, clobbers
, len
);
192 unsigned paravirt_patch_insns(void *site
, unsigned len
,
193 const char *start
, const char *end
)
195 unsigned insn_len
= end
- start
;
197 if (insn_len
> len
|| start
== NULL
)
200 memcpy(site
, start
, insn_len
);
207 paravirt_ops
.init_IRQ();
210 static void native_flush_tlb(void)
212 __native_flush_tlb();
216 * Global pages have to be flushed a bit differently. Not a real
217 * performance problem because this does not happen often.
219 static void native_flush_tlb_global(void)
221 __native_flush_tlb_global();
224 static void native_flush_tlb_single(unsigned long addr
)
226 __native_flush_tlb_single(addr
);
229 /* These are in entry.S */
230 extern void native_iret(void);
231 extern void native_irq_enable_sysexit(void);
233 static int __init
print_banner(void)
235 paravirt_ops
.banner();
238 core_initcall(print_banner
);
240 static struct resource reserve_ioports
= {
242 .end
= IO_SPACE_LIMIT
,
243 .name
= "paravirt-ioport",
244 .flags
= IORESOURCE_IO
| IORESOURCE_BUSY
,
247 static struct resource reserve_iomem
= {
250 .name
= "paravirt-iomem",
251 .flags
= IORESOURCE_MEM
| IORESOURCE_BUSY
,
255 * Reserve the whole legacy IO space to prevent any legacy drivers
256 * from wasting time probing for their hardware. This is a fairly
257 * brute-force approach to disabling all non-virtual drivers.
259 * Note that this must be called very early to have any effect.
261 int paravirt_disable_iospace(void)
265 ret
= request_resource(&ioport_resource
, &reserve_ioports
);
267 ret
= request_resource(&iomem_resource
, &reserve_iomem
);
269 release_resource(&reserve_ioports
);
275 struct paravirt_ops paravirt_ops
= {
276 .name
= "bare hardware",
277 .paravirt_enabled
= 0,
279 .shared_kernel_pmd
= 1, /* Only used when CONFIG_X86_PAE is set */
281 .patch
= native_patch
,
282 .banner
= default_banner
,
283 .arch_setup
= paravirt_nop
,
284 .memory_setup
= machine_specific_memory_setup
,
285 .get_wallclock
= native_get_wallclock
,
286 .set_wallclock
= native_set_wallclock
,
287 .time_init
= hpet_time_init
,
288 .init_IRQ
= native_init_IRQ
,
290 .cpuid
= native_cpuid
,
291 .get_debugreg
= native_get_debugreg
,
292 .set_debugreg
= native_set_debugreg
,
294 .read_cr0
= native_read_cr0
,
295 .write_cr0
= native_write_cr0
,
296 .read_cr2
= native_read_cr2
,
297 .write_cr2
= native_write_cr2
,
298 .read_cr3
= native_read_cr3
,
299 .write_cr3
= native_write_cr3
,
300 .read_cr4
= native_read_cr4
,
301 .read_cr4_safe
= native_read_cr4_safe
,
302 .write_cr4
= native_write_cr4
,
303 .save_fl
= native_save_fl
,
304 .restore_fl
= native_restore_fl
,
305 .irq_disable
= native_irq_disable
,
306 .irq_enable
= native_irq_enable
,
307 .safe_halt
= native_safe_halt
,
309 .wbinvd
= native_wbinvd
,
310 .read_msr
= native_read_msr_safe
,
311 .write_msr
= native_write_msr_safe
,
312 .read_tsc
= native_read_tsc
,
313 .read_pmc
= native_read_pmc
,
314 .sched_clock
= native_sched_clock
,
315 .get_cpu_khz
= native_calculate_cpu_khz
,
316 .load_tr_desc
= native_load_tr_desc
,
317 .set_ldt
= native_set_ldt
,
318 .load_gdt
= native_load_gdt
,
319 .load_idt
= native_load_idt
,
320 .store_gdt
= native_store_gdt
,
321 .store_idt
= native_store_idt
,
322 .store_tr
= native_store_tr
,
323 .load_tls
= native_load_tls
,
324 .write_ldt_entry
= write_dt_entry
,
325 .write_gdt_entry
= write_dt_entry
,
326 .write_idt_entry
= write_dt_entry
,
327 .load_esp0
= native_load_esp0
,
329 .set_iopl_mask
= native_set_iopl_mask
,
330 .io_delay
= native_io_delay
,
332 #ifdef CONFIG_X86_LOCAL_APIC
333 .apic_write
= native_apic_write
,
334 .apic_write_atomic
= native_apic_write_atomic
,
335 .apic_read
= native_apic_read
,
336 .setup_boot_clock
= setup_boot_APIC_clock
,
337 .setup_secondary_clock
= setup_secondary_APIC_clock
,
338 .startup_ipi_hook
= paravirt_nop
,
340 .set_lazy_mode
= paravirt_nop
,
342 .pagetable_setup_start
= native_pagetable_setup_start
,
343 .pagetable_setup_done
= native_pagetable_setup_done
,
345 .flush_tlb_user
= native_flush_tlb
,
346 .flush_tlb_kernel
= native_flush_tlb_global
,
347 .flush_tlb_single
= native_flush_tlb_single
,
348 .flush_tlb_others
= native_flush_tlb_others
,
350 .alloc_pt
= paravirt_nop
,
351 .alloc_pd
= paravirt_nop
,
352 .alloc_pd_clone
= paravirt_nop
,
353 .release_pt
= paravirt_nop
,
354 .release_pd
= paravirt_nop
,
356 .set_pte
= native_set_pte
,
357 .set_pte_at
= native_set_pte_at
,
358 .set_pmd
= native_set_pmd
,
359 .pte_update
= paravirt_nop
,
360 .pte_update_defer
= paravirt_nop
,
362 #ifdef CONFIG_HIGHPTE
363 .kmap_atomic_pte
= kmap_atomic
,
366 #ifdef CONFIG_X86_PAE
367 .set_pte_atomic
= native_set_pte_atomic
,
368 .set_pte_present
= native_set_pte_present
,
369 .set_pud
= native_set_pud
,
370 .pte_clear
= native_pte_clear
,
371 .pmd_clear
= native_pmd_clear
,
373 .pmd_val
= native_pmd_val
,
374 .make_pmd
= native_make_pmd
,
377 .pte_val
= native_pte_val
,
378 .pgd_val
= native_pgd_val
,
380 .make_pte
= native_make_pte
,
381 .make_pgd
= native_make_pgd
,
383 .irq_enable_sysexit
= native_irq_enable_sysexit
,
386 .dup_mmap
= paravirt_nop
,
387 .exit_mmap
= paravirt_nop
,
388 .activate_mm
= paravirt_nop
,
391 EXPORT_SYMBOL(paravirt_ops
);