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/kvm_para.h>
24 #include <linux/slab.h>
28 #include <asm/kvm_ppc.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_INST_MFMSR 0x7c0000a6
47 #define KVM_INST_MFSPR_SPRG0 0x7c1042a6
48 #define KVM_INST_MFSPR_SPRG1 0x7c1142a6
49 #define KVM_INST_MFSPR_SPRG2 0x7c1242a6
50 #define KVM_INST_MFSPR_SPRG3 0x7c1342a6
51 #define KVM_INST_MFSPR_SRR0 0x7c1a02a6
52 #define KVM_INST_MFSPR_SRR1 0x7c1b02a6
53 #define KVM_INST_MFSPR_DAR 0x7c1302a6
54 #define KVM_INST_MFSPR_DSISR 0x7c1202a6
56 #define KVM_INST_MTSPR_SPRG0 0x7c1043a6
57 #define KVM_INST_MTSPR_SPRG1 0x7c1143a6
58 #define KVM_INST_MTSPR_SPRG2 0x7c1243a6
59 #define KVM_INST_MTSPR_SPRG3 0x7c1343a6
60 #define KVM_INST_MTSPR_SRR0 0x7c1a03a6
61 #define KVM_INST_MTSPR_SRR1 0x7c1b03a6
62 #define KVM_INST_MTSPR_DAR 0x7c1303a6
63 #define KVM_INST_MTSPR_DSISR 0x7c1203a6
65 #define KVM_INST_TLBSYNC 0x7c00046c
67 static bool kvm_patching_worked = true;
69 static inline void kvm_patch_ins(u32 *inst, u32 new_inst)
72 flush_icache_range((ulong)inst, (ulong)inst + 4);
75 static void kvm_patch_ins_ld(u32 *inst, long addr, u32 rt)
78 kvm_patch_ins(inst, KVM_INST_LD | rt | (addr & 0x0000fffc));
80 kvm_patch_ins(inst, KVM_INST_LWZ | rt | ((addr + 4) & 0x0000fffc));
84 static void kvm_patch_ins_lwz(u32 *inst, long addr, u32 rt)
86 kvm_patch_ins(inst, KVM_INST_LWZ | rt | (addr & 0x0000ffff));
89 static void kvm_patch_ins_std(u32 *inst, long addr, u32 rt)
92 kvm_patch_ins(inst, KVM_INST_STD | rt | (addr & 0x0000fffc));
94 kvm_patch_ins(inst, KVM_INST_STW | rt | ((addr + 4) & 0x0000fffc));
98 static void kvm_patch_ins_stw(u32 *inst, long addr, u32 rt)
100 kvm_patch_ins(inst, KVM_INST_STW | rt | (addr & 0x0000fffc));
103 static void kvm_patch_ins_nop(u32 *inst)
105 kvm_patch_ins(inst, KVM_INST_NOP);
108 static void kvm_map_magic_page(void *data)
110 kvm_hypercall2(KVM_HC_PPC_MAP_MAGIC_PAGE,
111 KVM_MAGIC_PAGE, /* Physical Address */
112 KVM_MAGIC_PAGE); /* Effective Address */
115 static void kvm_check_ins(u32 *inst)
118 u32 inst_no_rt = _inst & ~KVM_MASK_RT;
119 u32 inst_rt = _inst & KVM_MASK_RT;
121 switch (inst_no_rt) {
124 kvm_patch_ins_ld(inst, magic_var(msr), inst_rt);
126 case KVM_INST_MFSPR_SPRG0:
127 kvm_patch_ins_ld(inst, magic_var(sprg0), inst_rt);
129 case KVM_INST_MFSPR_SPRG1:
130 kvm_patch_ins_ld(inst, magic_var(sprg1), inst_rt);
132 case KVM_INST_MFSPR_SPRG2:
133 kvm_patch_ins_ld(inst, magic_var(sprg2), inst_rt);
135 case KVM_INST_MFSPR_SPRG3:
136 kvm_patch_ins_ld(inst, magic_var(sprg3), inst_rt);
138 case KVM_INST_MFSPR_SRR0:
139 kvm_patch_ins_ld(inst, magic_var(srr0), inst_rt);
141 case KVM_INST_MFSPR_SRR1:
142 kvm_patch_ins_ld(inst, magic_var(srr1), inst_rt);
144 case KVM_INST_MFSPR_DAR:
145 kvm_patch_ins_ld(inst, magic_var(dar), inst_rt);
147 case KVM_INST_MFSPR_DSISR:
148 kvm_patch_ins_lwz(inst, magic_var(dsisr), inst_rt);
152 case KVM_INST_MTSPR_SPRG0:
153 kvm_patch_ins_std(inst, magic_var(sprg0), inst_rt);
155 case KVM_INST_MTSPR_SPRG1:
156 kvm_patch_ins_std(inst, magic_var(sprg1), inst_rt);
158 case KVM_INST_MTSPR_SPRG2:
159 kvm_patch_ins_std(inst, magic_var(sprg2), inst_rt);
161 case KVM_INST_MTSPR_SPRG3:
162 kvm_patch_ins_std(inst, magic_var(sprg3), inst_rt);
164 case KVM_INST_MTSPR_SRR0:
165 kvm_patch_ins_std(inst, magic_var(srr0), inst_rt);
167 case KVM_INST_MTSPR_SRR1:
168 kvm_patch_ins_std(inst, magic_var(srr1), inst_rt);
170 case KVM_INST_MTSPR_DAR:
171 kvm_patch_ins_std(inst, magic_var(dar), inst_rt);
173 case KVM_INST_MTSPR_DSISR:
174 kvm_patch_ins_stw(inst, magic_var(dsisr), inst_rt);
178 case KVM_INST_TLBSYNC:
179 kvm_patch_ins_nop(inst);
187 static void kvm_use_magic_page(void)
193 /* Tell the host to map the magic page to -4096 on all CPUs */
194 on_each_cpu(kvm_map_magic_page, NULL, 1);
196 /* Quick self-test to see if the mapping works */
197 if (__get_user(tmp, (u32*)KVM_MAGIC_PAGE)) {
198 kvm_patching_worked = false;
202 /* Now loop through all code and find instructions */
203 start = (void*)_stext;
206 for (p = start; p < end; p++)
209 printk(KERN_INFO "KVM: Live patching for a fast VM %s\n",
210 kvm_patching_worked ? "worked" : "failed");
213 unsigned long kvm_hypercall(unsigned long *in,
217 unsigned long register r0 asm("r0");
218 unsigned long register r3 asm("r3") = in[0];
219 unsigned long register r4 asm("r4") = in[1];
220 unsigned long register r5 asm("r5") = in[2];
221 unsigned long register r6 asm("r6") = in[3];
222 unsigned long register r7 asm("r7") = in[4];
223 unsigned long register r8 asm("r8") = in[5];
224 unsigned long register r9 asm("r9") = in[6];
225 unsigned long register r10 asm("r10") = in[7];
226 unsigned long register r11 asm("r11") = nr;
227 unsigned long register r12 asm("r12");
229 asm volatile("bl kvm_hypercall_start"
230 : "=r"(r0), "=r"(r3), "=r"(r4), "=r"(r5), "=r"(r6),
231 "=r"(r7), "=r"(r8), "=r"(r9), "=r"(r10), "=r"(r11),
233 : "r"(r3), "r"(r4), "r"(r5), "r"(r6), "r"(r7), "r"(r8),
234 "r"(r9), "r"(r10), "r"(r11)
235 : "memory", "cc", "xer", "ctr", "lr");
248 EXPORT_SYMBOL_GPL(kvm_hypercall);
250 static int kvm_para_setup(void)
252 extern u32 kvm_hypercall_start;
253 struct device_node *hyper_node;
257 hyper_node = of_find_node_by_path("/hypervisor");
261 insts = (u32*)of_get_property(hyper_node, "hcall-instructions", &len);
267 for (i = 0; i < (len / 4); i++)
268 kvm_patch_ins(&(&kvm_hypercall_start)[i], insts[i]);
273 static int __init kvm_guest_init(void)
275 if (!kvm_para_available())
278 if (kvm_para_setup())
281 if (kvm_para_has_feature(KVM_FEATURE_MAGIC_PAGE))
282 kvm_use_magic_page();
287 postcore_initcall(kvm_guest_init);