2 * Copyright (C) 2010 SUSE Linux Products GmbH. All rights reserved.
5 * Alexander Graf <agraf@suse.de>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License, version 2, as
9 * published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21 #include <linux/kvm_host.h>
22 #include <linux/init.h>
23 #include <linux/export.h>
24 #include <linux/kvm_para.h>
25 #include <linux/slab.h>
29 #include <asm/sections.h>
30 #include <asm/cacheflush.h>
31 #include <asm/disassemble.h>
33 #define KVM_MAGIC_PAGE (-4096L)
34 #define magic_var(x) KVM_MAGIC_PAGE + offsetof(struct kvm_vcpu_arch_shared, x)
36 #define KVM_INST_LWZ 0x80000000
37 #define KVM_INST_STW 0x90000000
38 #define KVM_INST_LD 0xe8000000
39 #define KVM_INST_STD 0xf8000000
40 #define KVM_INST_NOP 0x60000000
41 #define KVM_INST_B 0x48000000
42 #define KVM_INST_B_MASK 0x03ffffff
43 #define KVM_INST_B_MAX 0x01ffffff
45 #define KVM_MASK_RT 0x03e00000
46 #define KVM_RT_30 0x03c00000
47 #define KVM_MASK_RB 0x0000f800
48 #define KVM_INST_MFMSR 0x7c0000a6
49 #define KVM_INST_MFSPR_SPRG0 0x7c1042a6
50 #define KVM_INST_MFSPR_SPRG1 0x7c1142a6
51 #define KVM_INST_MFSPR_SPRG2 0x7c1242a6
52 #define KVM_INST_MFSPR_SPRG3 0x7c1342a6
53 #define KVM_INST_MFSPR_SRR0 0x7c1a02a6
54 #define KVM_INST_MFSPR_SRR1 0x7c1b02a6
55 #define KVM_INST_MFSPR_DAR 0x7c1302a6
56 #define KVM_INST_MFSPR_DSISR 0x7c1202a6
58 #define KVM_INST_MTSPR_SPRG0 0x7c1043a6
59 #define KVM_INST_MTSPR_SPRG1 0x7c1143a6
60 #define KVM_INST_MTSPR_SPRG2 0x7c1243a6
61 #define KVM_INST_MTSPR_SPRG3 0x7c1343a6
62 #define KVM_INST_MTSPR_SRR0 0x7c1a03a6
63 #define KVM_INST_MTSPR_SRR1 0x7c1b03a6
64 #define KVM_INST_MTSPR_DAR 0x7c1303a6
65 #define KVM_INST_MTSPR_DSISR 0x7c1203a6
67 #define KVM_INST_TLBSYNC 0x7c00046c
68 #define KVM_INST_MTMSRD_L0 0x7c000164
69 #define KVM_INST_MTMSRD_L1 0x7c010164
70 #define KVM_INST_MTMSR 0x7c000124
72 #define KVM_INST_WRTEEI_0 0x7c000146
73 #define KVM_INST_WRTEEI_1 0x7c008146
75 #define KVM_INST_MTSRIN 0x7c0001e4
77 static bool kvm_patching_worked
= true;
78 static char kvm_tmp
[1024 * 1024];
79 static int kvm_tmp_index
;
81 static inline void kvm_patch_ins(u32
*inst
, u32 new_inst
)
84 flush_icache_range((ulong
)inst
, (ulong
)inst
+ 4);
87 static void kvm_patch_ins_ll(u32
*inst
, long addr
, u32 rt
)
90 kvm_patch_ins(inst
, KVM_INST_LD
| rt
| (addr
& 0x0000fffc));
92 kvm_patch_ins(inst
, KVM_INST_LWZ
| rt
| (addr
& 0x0000fffc));
96 static void kvm_patch_ins_ld(u32
*inst
, long addr
, u32 rt
)
99 kvm_patch_ins(inst
, KVM_INST_LD
| rt
| (addr
& 0x0000fffc));
101 kvm_patch_ins(inst
, KVM_INST_LWZ
| rt
| ((addr
+ 4) & 0x0000fffc));
105 static void kvm_patch_ins_lwz(u32
*inst
, long addr
, u32 rt
)
107 kvm_patch_ins(inst
, KVM_INST_LWZ
| rt
| (addr
& 0x0000ffff));
110 static void kvm_patch_ins_std(u32
*inst
, long addr
, u32 rt
)
113 kvm_patch_ins(inst
, KVM_INST_STD
| rt
| (addr
& 0x0000fffc));
115 kvm_patch_ins(inst
, KVM_INST_STW
| rt
| ((addr
+ 4) & 0x0000fffc));
119 static void kvm_patch_ins_stw(u32
*inst
, long addr
, u32 rt
)
121 kvm_patch_ins(inst
, KVM_INST_STW
| rt
| (addr
& 0x0000fffc));
124 static void kvm_patch_ins_nop(u32
*inst
)
126 kvm_patch_ins(inst
, KVM_INST_NOP
);
129 static void kvm_patch_ins_b(u32
*inst
, int addr
)
131 #if defined(CONFIG_RELOCATABLE) && defined(CONFIG_PPC_BOOK3S)
132 /* On relocatable kernels interrupts handlers and our code
133 can be in different regions, so we don't patch them */
135 if ((ulong
)inst
< (ulong
)&__end_interrupts
)
139 kvm_patch_ins(inst
, KVM_INST_B
| (addr
& KVM_INST_B_MASK
));
142 static u32
*kvm_alloc(int len
)
146 if ((kvm_tmp_index
+ len
) > ARRAY_SIZE(kvm_tmp
)) {
147 printk(KERN_ERR
"KVM: No more space (%d + %d)\n",
149 kvm_patching_worked
= false;
153 p
= (void*)&kvm_tmp
[kvm_tmp_index
];
154 kvm_tmp_index
+= len
;
159 extern u32 kvm_emulate_mtmsrd_branch_offs
;
160 extern u32 kvm_emulate_mtmsrd_reg_offs
;
161 extern u32 kvm_emulate_mtmsrd_orig_ins_offs
;
162 extern u32 kvm_emulate_mtmsrd_len
;
163 extern u32 kvm_emulate_mtmsrd
[];
165 static void kvm_patch_ins_mtmsrd(u32
*inst
, u32 rt
)
172 p
= kvm_alloc(kvm_emulate_mtmsrd_len
* 4);
176 /* Find out where we are and put everything there */
177 distance_start
= (ulong
)p
- (ulong
)inst
;
178 next_inst
= ((ulong
)inst
+ 4);
179 distance_end
= next_inst
- (ulong
)&p
[kvm_emulate_mtmsrd_branch_offs
];
181 /* Make sure we only write valid b instructions */
182 if (distance_start
> KVM_INST_B_MAX
) {
183 kvm_patching_worked
= false;
187 /* Modify the chunk to fit the invocation */
188 memcpy(p
, kvm_emulate_mtmsrd
, kvm_emulate_mtmsrd_len
* 4);
189 p
[kvm_emulate_mtmsrd_branch_offs
] |= distance_end
& KVM_INST_B_MASK
;
190 switch (get_rt(rt
)) {
192 kvm_patch_ins_ll(&p
[kvm_emulate_mtmsrd_reg_offs
],
193 magic_var(scratch2
), KVM_RT_30
);
196 kvm_patch_ins_ll(&p
[kvm_emulate_mtmsrd_reg_offs
],
197 magic_var(scratch1
), KVM_RT_30
);
200 p
[kvm_emulate_mtmsrd_reg_offs
] |= rt
;
204 p
[kvm_emulate_mtmsrd_orig_ins_offs
] = *inst
;
205 flush_icache_range((ulong
)p
, (ulong
)p
+ kvm_emulate_mtmsrd_len
* 4);
207 /* Patch the invocation */
208 kvm_patch_ins_b(inst
, distance_start
);
211 extern u32 kvm_emulate_mtmsr_branch_offs
;
212 extern u32 kvm_emulate_mtmsr_reg1_offs
;
213 extern u32 kvm_emulate_mtmsr_reg2_offs
;
214 extern u32 kvm_emulate_mtmsr_orig_ins_offs
;
215 extern u32 kvm_emulate_mtmsr_len
;
216 extern u32 kvm_emulate_mtmsr
[];
218 static void kvm_patch_ins_mtmsr(u32
*inst
, u32 rt
)
225 p
= kvm_alloc(kvm_emulate_mtmsr_len
* 4);
229 /* Find out where we are and put everything there */
230 distance_start
= (ulong
)p
- (ulong
)inst
;
231 next_inst
= ((ulong
)inst
+ 4);
232 distance_end
= next_inst
- (ulong
)&p
[kvm_emulate_mtmsr_branch_offs
];
234 /* Make sure we only write valid b instructions */
235 if (distance_start
> KVM_INST_B_MAX
) {
236 kvm_patching_worked
= false;
240 /* Modify the chunk to fit the invocation */
241 memcpy(p
, kvm_emulate_mtmsr
, kvm_emulate_mtmsr_len
* 4);
242 p
[kvm_emulate_mtmsr_branch_offs
] |= distance_end
& KVM_INST_B_MASK
;
244 /* Make clobbered registers work too */
245 switch (get_rt(rt
)) {
247 kvm_patch_ins_ll(&p
[kvm_emulate_mtmsr_reg1_offs
],
248 magic_var(scratch2
), KVM_RT_30
);
249 kvm_patch_ins_ll(&p
[kvm_emulate_mtmsr_reg2_offs
],
250 magic_var(scratch2
), KVM_RT_30
);
253 kvm_patch_ins_ll(&p
[kvm_emulate_mtmsr_reg1_offs
],
254 magic_var(scratch1
), KVM_RT_30
);
255 kvm_patch_ins_ll(&p
[kvm_emulate_mtmsr_reg2_offs
],
256 magic_var(scratch1
), KVM_RT_30
);
259 p
[kvm_emulate_mtmsr_reg1_offs
] |= rt
;
260 p
[kvm_emulate_mtmsr_reg2_offs
] |= rt
;
264 p
[kvm_emulate_mtmsr_orig_ins_offs
] = *inst
;
265 flush_icache_range((ulong
)p
, (ulong
)p
+ kvm_emulate_mtmsr_len
* 4);
267 /* Patch the invocation */
268 kvm_patch_ins_b(inst
, distance_start
);
273 extern u32 kvm_emulate_wrteei_branch_offs
;
274 extern u32 kvm_emulate_wrteei_ee_offs
;
275 extern u32 kvm_emulate_wrteei_len
;
276 extern u32 kvm_emulate_wrteei
[];
278 static void kvm_patch_ins_wrteei(u32
*inst
)
285 p
= kvm_alloc(kvm_emulate_wrteei_len
* 4);
289 /* Find out where we are and put everything there */
290 distance_start
= (ulong
)p
- (ulong
)inst
;
291 next_inst
= ((ulong
)inst
+ 4);
292 distance_end
= next_inst
- (ulong
)&p
[kvm_emulate_wrteei_branch_offs
];
294 /* Make sure we only write valid b instructions */
295 if (distance_start
> KVM_INST_B_MAX
) {
296 kvm_patching_worked
= false;
300 /* Modify the chunk to fit the invocation */
301 memcpy(p
, kvm_emulate_wrteei
, kvm_emulate_wrteei_len
* 4);
302 p
[kvm_emulate_wrteei_branch_offs
] |= distance_end
& KVM_INST_B_MASK
;
303 p
[kvm_emulate_wrteei_ee_offs
] |= (*inst
& MSR_EE
);
304 flush_icache_range((ulong
)p
, (ulong
)p
+ kvm_emulate_wrteei_len
* 4);
306 /* Patch the invocation */
307 kvm_patch_ins_b(inst
, distance_start
);
312 #ifdef CONFIG_PPC_BOOK3S_32
314 extern u32 kvm_emulate_mtsrin_branch_offs
;
315 extern u32 kvm_emulate_mtsrin_reg1_offs
;
316 extern u32 kvm_emulate_mtsrin_reg2_offs
;
317 extern u32 kvm_emulate_mtsrin_orig_ins_offs
;
318 extern u32 kvm_emulate_mtsrin_len
;
319 extern u32 kvm_emulate_mtsrin
[];
321 static void kvm_patch_ins_mtsrin(u32
*inst
, u32 rt
, u32 rb
)
328 p
= kvm_alloc(kvm_emulate_mtsrin_len
* 4);
332 /* Find out where we are and put everything there */
333 distance_start
= (ulong
)p
- (ulong
)inst
;
334 next_inst
= ((ulong
)inst
+ 4);
335 distance_end
= next_inst
- (ulong
)&p
[kvm_emulate_mtsrin_branch_offs
];
337 /* Make sure we only write valid b instructions */
338 if (distance_start
> KVM_INST_B_MAX
) {
339 kvm_patching_worked
= false;
343 /* Modify the chunk to fit the invocation */
344 memcpy(p
, kvm_emulate_mtsrin
, kvm_emulate_mtsrin_len
* 4);
345 p
[kvm_emulate_mtsrin_branch_offs
] |= distance_end
& KVM_INST_B_MASK
;
346 p
[kvm_emulate_mtsrin_reg1_offs
] |= (rb
<< 10);
347 p
[kvm_emulate_mtsrin_reg2_offs
] |= rt
;
348 p
[kvm_emulate_mtsrin_orig_ins_offs
] = *inst
;
349 flush_icache_range((ulong
)p
, (ulong
)p
+ kvm_emulate_mtsrin_len
* 4);
351 /* Patch the invocation */
352 kvm_patch_ins_b(inst
, distance_start
);
357 static void kvm_map_magic_page(void *data
)
359 u32
*features
= data
;
364 in
[0] = KVM_MAGIC_PAGE
;
365 in
[1] = KVM_MAGIC_PAGE
;
367 kvm_hypercall(in
, out
, HC_VENDOR_KVM
| KVM_HC_PPC_MAP_MAGIC_PAGE
);
372 static void kvm_check_ins(u32
*inst
, u32 features
)
375 u32 inst_no_rt
= _inst
& ~KVM_MASK_RT
;
376 u32 inst_rt
= _inst
& KVM_MASK_RT
;
378 switch (inst_no_rt
) {
381 kvm_patch_ins_ld(inst
, magic_var(msr
), inst_rt
);
383 case KVM_INST_MFSPR_SPRG0
:
384 kvm_patch_ins_ld(inst
, magic_var(sprg0
), inst_rt
);
386 case KVM_INST_MFSPR_SPRG1
:
387 kvm_patch_ins_ld(inst
, magic_var(sprg1
), inst_rt
);
389 case KVM_INST_MFSPR_SPRG2
:
390 kvm_patch_ins_ld(inst
, magic_var(sprg2
), inst_rt
);
392 case KVM_INST_MFSPR_SPRG3
:
393 kvm_patch_ins_ld(inst
, magic_var(sprg3
), inst_rt
);
395 case KVM_INST_MFSPR_SRR0
:
396 kvm_patch_ins_ld(inst
, magic_var(srr0
), inst_rt
);
398 case KVM_INST_MFSPR_SRR1
:
399 kvm_patch_ins_ld(inst
, magic_var(srr1
), inst_rt
);
401 case KVM_INST_MFSPR_DAR
:
402 kvm_patch_ins_ld(inst
, magic_var(dar
), inst_rt
);
404 case KVM_INST_MFSPR_DSISR
:
405 kvm_patch_ins_lwz(inst
, magic_var(dsisr
), inst_rt
);
409 case KVM_INST_MTSPR_SPRG0
:
410 kvm_patch_ins_std(inst
, magic_var(sprg0
), inst_rt
);
412 case KVM_INST_MTSPR_SPRG1
:
413 kvm_patch_ins_std(inst
, magic_var(sprg1
), inst_rt
);
415 case KVM_INST_MTSPR_SPRG2
:
416 kvm_patch_ins_std(inst
, magic_var(sprg2
), inst_rt
);
418 case KVM_INST_MTSPR_SPRG3
:
419 kvm_patch_ins_std(inst
, magic_var(sprg3
), inst_rt
);
421 case KVM_INST_MTSPR_SRR0
:
422 kvm_patch_ins_std(inst
, magic_var(srr0
), inst_rt
);
424 case KVM_INST_MTSPR_SRR1
:
425 kvm_patch_ins_std(inst
, magic_var(srr1
), inst_rt
);
427 case KVM_INST_MTSPR_DAR
:
428 kvm_patch_ins_std(inst
, magic_var(dar
), inst_rt
);
430 case KVM_INST_MTSPR_DSISR
:
431 kvm_patch_ins_stw(inst
, magic_var(dsisr
), inst_rt
);
435 case KVM_INST_TLBSYNC
:
436 kvm_patch_ins_nop(inst
);
440 case KVM_INST_MTMSRD_L1
:
441 kvm_patch_ins_mtmsrd(inst
, inst_rt
);
444 case KVM_INST_MTMSRD_L0
:
445 kvm_patch_ins_mtmsr(inst
, inst_rt
);
449 switch (inst_no_rt
& ~KVM_MASK_RB
) {
450 #ifdef CONFIG_PPC_BOOK3S_32
451 case KVM_INST_MTSRIN
:
452 if (features
& KVM_MAGIC_FEAT_SR
) {
453 u32 inst_rb
= _inst
& KVM_MASK_RB
;
454 kvm_patch_ins_mtsrin(inst
, inst_rt
, inst_rb
);
463 case KVM_INST_WRTEEI_0
:
464 case KVM_INST_WRTEEI_1
:
465 kvm_patch_ins_wrteei(inst
);
471 static void kvm_use_magic_page(void)
478 /* Tell the host to map the magic page to -4096 on all CPUs */
479 on_each_cpu(kvm_map_magic_page
, &features
, 1);
481 /* Quick self-test to see if the mapping works */
482 if (__get_user(tmp
, (u32
*)KVM_MAGIC_PAGE
)) {
483 kvm_patching_worked
= false;
487 /* Now loop through all code and find instructions */
488 start
= (void*)_stext
;
491 for (p
= start
; p
< end
; p
++)
492 kvm_check_ins(p
, features
);
494 printk(KERN_INFO
"KVM: Live patching for a fast VM %s\n",
495 kvm_patching_worked
? "worked" : "failed");
498 unsigned long kvm_hypercall(unsigned long *in
,
502 unsigned long register r0
asm("r0");
503 unsigned long register r3
asm("r3") = in
[0];
504 unsigned long register r4
asm("r4") = in
[1];
505 unsigned long register r5
asm("r5") = in
[2];
506 unsigned long register r6
asm("r6") = in
[3];
507 unsigned long register r7
asm("r7") = in
[4];
508 unsigned long register r8
asm("r8") = in
[5];
509 unsigned long register r9
asm("r9") = in
[6];
510 unsigned long register r10
asm("r10") = in
[7];
511 unsigned long register r11
asm("r11") = nr
;
512 unsigned long register r12
asm("r12");
514 asm volatile("bl kvm_hypercall_start"
515 : "=r"(r0
), "=r"(r3
), "=r"(r4
), "=r"(r5
), "=r"(r6
),
516 "=r"(r7
), "=r"(r8
), "=r"(r9
), "=r"(r10
), "=r"(r11
),
518 : "r"(r3
), "r"(r4
), "r"(r5
), "r"(r6
), "r"(r7
), "r"(r8
),
519 "r"(r9
), "r"(r10
), "r"(r11
)
520 : "memory", "cc", "xer", "ctr", "lr");
533 EXPORT_SYMBOL_GPL(kvm_hypercall
);
535 static int kvm_para_setup(void)
537 extern u32 kvm_hypercall_start
;
538 struct device_node
*hyper_node
;
542 hyper_node
= of_find_node_by_path("/hypervisor");
546 insts
= (u32
*)of_get_property(hyper_node
, "hcall-instructions", &len
);
552 for (i
= 0; i
< (len
/ 4); i
++)
553 kvm_patch_ins(&(&kvm_hypercall_start
)[i
], insts
[i
]);
558 static __init
void kvm_free_tmp(void)
560 unsigned long start
, end
;
562 start
= (ulong
)&kvm_tmp
[kvm_tmp_index
+ (PAGE_SIZE
- 1)] & PAGE_MASK
;
563 end
= (ulong
)&kvm_tmp
[ARRAY_SIZE(kvm_tmp
)] & PAGE_MASK
;
565 /* Free the tmp space we don't need */
566 for (; start
< end
; start
+= PAGE_SIZE
) {
567 ClearPageReserved(virt_to_page(start
));
568 init_page_count(virt_to_page(start
));
574 static int __init
kvm_guest_init(void)
576 if (!kvm_para_available())
579 if (kvm_para_setup())
582 if (kvm_para_has_feature(KVM_FEATURE_MAGIC_PAGE
))
583 kvm_use_magic_page();
585 #ifdef CONFIG_PPC_BOOK3S_64
596 postcore_initcall(kvm_guest_init
);