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 static bool kvm_patching_worked = true;
67 static inline void kvm_patch_ins(u32 *inst, u32 new_inst)
70 flush_icache_range((ulong)inst, (ulong)inst + 4);
73 static void kvm_patch_ins_ld(u32 *inst, long addr, u32 rt)
76 kvm_patch_ins(inst, KVM_INST_LD | rt | (addr & 0x0000fffc));
78 kvm_patch_ins(inst, KVM_INST_LWZ | rt | ((addr + 4) & 0x0000fffc));
82 static void kvm_patch_ins_lwz(u32 *inst, long addr, u32 rt)
84 kvm_patch_ins(inst, KVM_INST_LWZ | rt | (addr & 0x0000ffff));
87 static void kvm_patch_ins_std(u32 *inst, long addr, u32 rt)
90 kvm_patch_ins(inst, KVM_INST_STD | rt | (addr & 0x0000fffc));
92 kvm_patch_ins(inst, KVM_INST_STW | rt | ((addr + 4) & 0x0000fffc));
96 static void kvm_patch_ins_stw(u32 *inst, long addr, u32 rt)
98 kvm_patch_ins(inst, KVM_INST_STW | rt | (addr & 0x0000fffc));
101 static void kvm_map_magic_page(void *data)
103 kvm_hypercall2(KVM_HC_PPC_MAP_MAGIC_PAGE,
104 KVM_MAGIC_PAGE, /* Physical Address */
105 KVM_MAGIC_PAGE); /* Effective Address */
108 static void kvm_check_ins(u32 *inst)
111 u32 inst_no_rt = _inst & ~KVM_MASK_RT;
112 u32 inst_rt = _inst & KVM_MASK_RT;
114 switch (inst_no_rt) {
117 kvm_patch_ins_ld(inst, magic_var(msr), inst_rt);
119 case KVM_INST_MFSPR_SPRG0:
120 kvm_patch_ins_ld(inst, magic_var(sprg0), inst_rt);
122 case KVM_INST_MFSPR_SPRG1:
123 kvm_patch_ins_ld(inst, magic_var(sprg1), inst_rt);
125 case KVM_INST_MFSPR_SPRG2:
126 kvm_patch_ins_ld(inst, magic_var(sprg2), inst_rt);
128 case KVM_INST_MFSPR_SPRG3:
129 kvm_patch_ins_ld(inst, magic_var(sprg3), inst_rt);
131 case KVM_INST_MFSPR_SRR0:
132 kvm_patch_ins_ld(inst, magic_var(srr0), inst_rt);
134 case KVM_INST_MFSPR_SRR1:
135 kvm_patch_ins_ld(inst, magic_var(srr1), inst_rt);
137 case KVM_INST_MFSPR_DAR:
138 kvm_patch_ins_ld(inst, magic_var(dar), inst_rt);
140 case KVM_INST_MFSPR_DSISR:
141 kvm_patch_ins_lwz(inst, magic_var(dsisr), inst_rt);
145 case KVM_INST_MTSPR_SPRG0:
146 kvm_patch_ins_std(inst, magic_var(sprg0), inst_rt);
148 case KVM_INST_MTSPR_SPRG1:
149 kvm_patch_ins_std(inst, magic_var(sprg1), inst_rt);
151 case KVM_INST_MTSPR_SPRG2:
152 kvm_patch_ins_std(inst, magic_var(sprg2), inst_rt);
154 case KVM_INST_MTSPR_SPRG3:
155 kvm_patch_ins_std(inst, magic_var(sprg3), inst_rt);
157 case KVM_INST_MTSPR_SRR0:
158 kvm_patch_ins_std(inst, magic_var(srr0), inst_rt);
160 case KVM_INST_MTSPR_SRR1:
161 kvm_patch_ins_std(inst, magic_var(srr1), inst_rt);
163 case KVM_INST_MTSPR_DAR:
164 kvm_patch_ins_std(inst, magic_var(dar), inst_rt);
166 case KVM_INST_MTSPR_DSISR:
167 kvm_patch_ins_stw(inst, magic_var(dsisr), inst_rt);
175 static void kvm_use_magic_page(void)
181 /* Tell the host to map the magic page to -4096 on all CPUs */
182 on_each_cpu(kvm_map_magic_page, NULL, 1);
184 /* Quick self-test to see if the mapping works */
185 if (__get_user(tmp, (u32*)KVM_MAGIC_PAGE)) {
186 kvm_patching_worked = false;
190 /* Now loop through all code and find instructions */
191 start = (void*)_stext;
194 for (p = start; p < end; p++)
197 printk(KERN_INFO "KVM: Live patching for a fast VM %s\n",
198 kvm_patching_worked ? "worked" : "failed");
201 unsigned long kvm_hypercall(unsigned long *in,
205 unsigned long register r0 asm("r0");
206 unsigned long register r3 asm("r3") = in[0];
207 unsigned long register r4 asm("r4") = in[1];
208 unsigned long register r5 asm("r5") = in[2];
209 unsigned long register r6 asm("r6") = in[3];
210 unsigned long register r7 asm("r7") = in[4];
211 unsigned long register r8 asm("r8") = in[5];
212 unsigned long register r9 asm("r9") = in[6];
213 unsigned long register r10 asm("r10") = in[7];
214 unsigned long register r11 asm("r11") = nr;
215 unsigned long register r12 asm("r12");
217 asm volatile("bl kvm_hypercall_start"
218 : "=r"(r0), "=r"(r3), "=r"(r4), "=r"(r5), "=r"(r6),
219 "=r"(r7), "=r"(r8), "=r"(r9), "=r"(r10), "=r"(r11),
221 : "r"(r3), "r"(r4), "r"(r5), "r"(r6), "r"(r7), "r"(r8),
222 "r"(r9), "r"(r10), "r"(r11)
223 : "memory", "cc", "xer", "ctr", "lr");
236 EXPORT_SYMBOL_GPL(kvm_hypercall);
238 static int kvm_para_setup(void)
240 extern u32 kvm_hypercall_start;
241 struct device_node *hyper_node;
245 hyper_node = of_find_node_by_path("/hypervisor");
249 insts = (u32*)of_get_property(hyper_node, "hcall-instructions", &len);
255 for (i = 0; i < (len / 4); i++)
256 kvm_patch_ins(&(&kvm_hypercall_start)[i], insts[i]);
261 static int __init kvm_guest_init(void)
263 if (!kvm_para_available())
266 if (kvm_para_setup())
269 if (kvm_para_has_feature(KVM_FEATURE_MAGIC_PAGE))
270 kvm_use_magic_page();
275 postcore_initcall(kvm_guest_init);