KVM: change the way how lowest priority vcpu is calculated
[linux-2.6] / arch / ia64 / kernel / err_inject.c
1 /*
2  * err_inject.c -
3  *      1.) Inject errors to a processor.
4  *      2.) Query error injection capabilities.
5  * This driver along with user space code can be acting as an error
6  * injection tool.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
16  * NON INFRINGEMENT.  See the GNU General Public License for more
17  * details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  * Written by: Fenghua Yu <fenghua.yu@intel.com>, Intel Corporation
24  * Copyright (C) 2006, Intel Corp.  All rights reserved.
25  *
26  */
27 #include <linux/sysdev.h>
28 #include <linux/init.h>
29 #include <linux/mm.h>
30 #include <linux/cpu.h>
31 #include <linux/module.h>
32
33 #define ERR_INJ_DEBUG
34
35 #define ERR_DATA_BUFFER_SIZE 3          // Three 8-byte;
36
37 #define define_one_ro(name)                                             \
38 static SYSDEV_ATTR(name, 0444, show_##name, NULL)
39
40 #define define_one_rw(name)                                             \
41 static SYSDEV_ATTR(name, 0644, show_##name, store_##name)
42
43 static u64 call_start[NR_CPUS];
44 static u64 phys_addr[NR_CPUS];
45 static u64 err_type_info[NR_CPUS];
46 static u64 err_struct_info[NR_CPUS];
47 static struct {
48         u64 data1;
49         u64 data2;
50         u64 data3;
51 } __attribute__((__aligned__(16))) err_data_buffer[NR_CPUS];
52 static s64 status[NR_CPUS];
53 static u64 capabilities[NR_CPUS];
54 static u64 resources[NR_CPUS];
55
56 #define show(name)                                                      \
57 static ssize_t                                                          \
58 show_##name(struct sys_device *dev, struct sysdev_attribute *attr,      \
59                 char *buf)                                              \
60 {                                                                       \
61         u32 cpu=dev->id;                                                \
62         return sprintf(buf, "%lx\n", name[cpu]);                        \
63 }
64
65 #define store(name)                                                     \
66 static ssize_t                                                          \
67 store_##name(struct sys_device *dev, struct sysdev_attribute *attr,     \
68                                         const char *buf, size_t size)   \
69 {                                                                       \
70         unsigned int cpu=dev->id;                                       \
71         name[cpu] = simple_strtoull(buf, NULL, 16);                     \
72         return size;                                                    \
73 }
74
75 show(call_start)
76
77 /* It's user's responsibility to call the PAL procedure on a specific
78  * processor. The cpu number in driver is only used for storing data.
79  */
80 static ssize_t
81 store_call_start(struct sys_device *dev, struct sysdev_attribute *attr,
82                 const char *buf, size_t size)
83 {
84         unsigned int cpu=dev->id;
85         unsigned long call_start = simple_strtoull(buf, NULL, 16);
86
87 #ifdef ERR_INJ_DEBUG
88         printk(KERN_DEBUG "pal_mc_err_inject for cpu%d:\n", cpu);
89         printk(KERN_DEBUG "err_type_info=%lx,\n", err_type_info[cpu]);
90         printk(KERN_DEBUG "err_struct_info=%lx,\n", err_struct_info[cpu]);
91         printk(KERN_DEBUG "err_data_buffer=%lx, %lx, %lx.\n",
92                           err_data_buffer[cpu].data1,
93                           err_data_buffer[cpu].data2,
94                           err_data_buffer[cpu].data3);
95 #endif
96         switch (call_start) {
97             case 0: /* Do nothing. */
98                 break;
99             case 1: /* Call pal_mc_error_inject in physical mode. */
100                 status[cpu]=ia64_pal_mc_error_inject_phys(err_type_info[cpu],
101                                         err_struct_info[cpu],
102                                         ia64_tpa(&err_data_buffer[cpu]),
103                                         &capabilities[cpu],
104                                         &resources[cpu]);
105                 break;
106             case 2: /* Call pal_mc_error_inject in virtual mode. */
107                 status[cpu]=ia64_pal_mc_error_inject_virt(err_type_info[cpu],
108                                         err_struct_info[cpu],
109                                         ia64_tpa(&err_data_buffer[cpu]),
110                                         &capabilities[cpu],
111                                         &resources[cpu]);
112                 break;
113             default:
114                 status[cpu] = -EINVAL;
115                 break;
116         }
117
118 #ifdef ERR_INJ_DEBUG
119         printk(KERN_DEBUG "Returns: status=%d,\n", (int)status[cpu]);
120         printk(KERN_DEBUG "capapbilities=%lx,\n", capabilities[cpu]);
121         printk(KERN_DEBUG "resources=%lx\n", resources[cpu]);
122 #endif
123         return size;
124 }
125
126 show(err_type_info)
127 store(err_type_info)
128
129 static ssize_t
130 show_virtual_to_phys(struct sys_device *dev, struct sysdev_attribute *attr,
131                         char *buf)
132 {
133         unsigned int cpu=dev->id;
134         return sprintf(buf, "%lx\n", phys_addr[cpu]);
135 }
136
137 static ssize_t
138 store_virtual_to_phys(struct sys_device *dev, struct sysdev_attribute *attr,
139                         const char *buf, size_t size)
140 {
141         unsigned int cpu=dev->id;
142         u64 virt_addr=simple_strtoull(buf, NULL, 16);
143         int ret;
144
145         ret = get_user_pages(current, current->mm, virt_addr,
146                         1, VM_READ, 0, NULL, NULL);
147         if (ret<=0) {
148 #ifdef ERR_INJ_DEBUG
149                 printk("Virtual address %lx is not existing.\n",virt_addr);
150 #endif
151                 return -EINVAL;
152         }
153
154         phys_addr[cpu] = ia64_tpa(virt_addr);
155         return size;
156 }
157
158 show(err_struct_info)
159 store(err_struct_info)
160
161 static ssize_t
162 show_err_data_buffer(struct sys_device *dev,
163                         struct sysdev_attribute *attr, char *buf)
164 {
165         unsigned int cpu=dev->id;
166
167         return sprintf(buf, "%lx, %lx, %lx\n",
168                         err_data_buffer[cpu].data1,
169                         err_data_buffer[cpu].data2,
170                         err_data_buffer[cpu].data3);
171 }
172
173 static ssize_t
174 store_err_data_buffer(struct sys_device *dev,
175                         struct sysdev_attribute *attr,
176                         const char *buf, size_t size)
177 {
178         unsigned int cpu=dev->id;
179         int ret;
180
181 #ifdef ERR_INJ_DEBUG
182         printk("write err_data_buffer=[%lx,%lx,%lx] on cpu%d\n",
183                  err_data_buffer[cpu].data1,
184                  err_data_buffer[cpu].data2,
185                  err_data_buffer[cpu].data3,
186                  cpu);
187 #endif
188         ret=sscanf(buf, "%lx, %lx, %lx",
189                         &err_data_buffer[cpu].data1,
190                         &err_data_buffer[cpu].data2,
191                         &err_data_buffer[cpu].data3);
192         if (ret!=ERR_DATA_BUFFER_SIZE)
193                 return -EINVAL;
194
195         return size;
196 }
197
198 show(status)
199 show(capabilities)
200 show(resources)
201
202 define_one_rw(call_start);
203 define_one_rw(err_type_info);
204 define_one_rw(err_struct_info);
205 define_one_rw(err_data_buffer);
206 define_one_rw(virtual_to_phys);
207 define_one_ro(status);
208 define_one_ro(capabilities);
209 define_one_ro(resources);
210
211 static struct attribute *default_attrs[] = {
212         &attr_call_start.attr,
213         &attr_virtual_to_phys.attr,
214         &attr_err_type_info.attr,
215         &attr_err_struct_info.attr,
216         &attr_err_data_buffer.attr,
217         &attr_status.attr,
218         &attr_capabilities.attr,
219         &attr_resources.attr,
220         NULL
221 };
222
223 static struct attribute_group err_inject_attr_group = {
224         .attrs = default_attrs,
225         .name = "err_inject"
226 };
227 /* Add/Remove err_inject interface for CPU device */
228 static int __cpuinit err_inject_add_dev(struct sys_device * sys_dev)
229 {
230         return sysfs_create_group(&sys_dev->kobj, &err_inject_attr_group);
231 }
232
233 static int __cpuinit err_inject_remove_dev(struct sys_device * sys_dev)
234 {
235         sysfs_remove_group(&sys_dev->kobj, &err_inject_attr_group);
236         return 0;
237 }
238 static int __cpuinit err_inject_cpu_callback(struct notifier_block *nfb,
239                 unsigned long action, void *hcpu)
240 {
241         unsigned int cpu = (unsigned long)hcpu;
242         struct sys_device *sys_dev;
243
244         sys_dev = get_cpu_sysdev(cpu);
245         switch (action) {
246         case CPU_ONLINE:
247         case CPU_ONLINE_FROZEN:
248                 err_inject_add_dev(sys_dev);
249                 break;
250         case CPU_DEAD:
251         case CPU_DEAD_FROZEN:
252                 err_inject_remove_dev(sys_dev);
253                 break;
254         }
255
256         return NOTIFY_OK;
257 }
258
259 static struct notifier_block __cpuinitdata err_inject_cpu_notifier =
260 {
261         .notifier_call = err_inject_cpu_callback,
262 };
263
264 static int __init
265 err_inject_init(void)
266 {
267         int i;
268
269 #ifdef ERR_INJ_DEBUG
270         printk(KERN_INFO "Enter error injection driver.\n");
271 #endif
272         for_each_online_cpu(i) {
273                 err_inject_cpu_callback(&err_inject_cpu_notifier, CPU_ONLINE,
274                                 (void *)(long)i);
275         }
276
277         register_hotcpu_notifier(&err_inject_cpu_notifier);
278
279         return 0;
280 }
281
282 static void __exit
283 err_inject_exit(void)
284 {
285         int i;
286         struct sys_device *sys_dev;
287
288 #ifdef ERR_INJ_DEBUG
289         printk(KERN_INFO "Exit error injection driver.\n");
290 #endif
291         for_each_online_cpu(i) {
292                 sys_dev = get_cpu_sysdev(i);
293                 sysfs_remove_group(&sys_dev->kobj, &err_inject_attr_group);
294         }
295         unregister_hotcpu_notifier(&err_inject_cpu_notifier);
296 }
297
298 module_init(err_inject_init);
299 module_exit(err_inject_exit);
300
301 MODULE_AUTHOR("Fenghua Yu <fenghua.yu@intel.com>");
302 MODULE_DESCRIPTION("MC error injection kernel sysfs interface");
303 MODULE_LICENSE("GPL");