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/device.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 DEVICE_ATTR(name, 0444, show_##name, NULL)
39
40 #define define_one_rw(name) \
41 static DEVICE_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 device *dev, struct device_attribute *attr, \
59 char *buf) \
60 { \
61 u32 cpu=dev->id; \
62 return sprintf(buf, "%llx\n", name[cpu]); \
63 }
64
65 #define store(name) \
66 static ssize_t \
67 store_##name(struct device *dev, struct device_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
show(call_start)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 device *dev, struct device_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=%llx,\n", err_type_info[cpu]);
90 printk(KERN_DEBUG "err_struct_info=%llx,\n", err_struct_info[cpu]);
91 printk(KERN_DEBUG "err_data_buffer=%llx, %llx, %llx.\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 "capabilities=%llx,\n", capabilities[cpu]);
121 printk(KERN_DEBUG "resources=%llx\n", resources[cpu]);
122 #endif
123 return size;
124 }
125
126 show(err_type_info)
store(err_type_info)127 store(err_type_info)
128
129 static ssize_t
130 show_virtual_to_phys(struct device *dev, struct device_attribute *attr,
131 char *buf)
132 {
133 unsigned int cpu=dev->id;
134 return sprintf(buf, "%llx\n", phys_addr[cpu]);
135 }
136
137 static ssize_t
store_virtual_to_phys(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)138 store_virtual_to_phys(struct device *dev, struct device_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_fast(virt_addr, 1, FOLL_WRITE, NULL);
146 if (ret<=0) {
147 #ifdef ERR_INJ_DEBUG
148 printk("Virtual address %llx is not existing.\n", virt_addr);
149 #endif
150 return -EINVAL;
151 }
152
153 phys_addr[cpu] = ia64_tpa(virt_addr);
154 return size;
155 }
156
157 show(err_struct_info)
store(err_struct_info)158 store(err_struct_info)
159
160 static ssize_t
161 show_err_data_buffer(struct device *dev,
162 struct device_attribute *attr, char *buf)
163 {
164 unsigned int cpu=dev->id;
165
166 return sprintf(buf, "%llx, %llx, %llx\n",
167 err_data_buffer[cpu].data1,
168 err_data_buffer[cpu].data2,
169 err_data_buffer[cpu].data3);
170 }
171
172 static ssize_t
store_err_data_buffer(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)173 store_err_data_buffer(struct device *dev,
174 struct device_attribute *attr,
175 const char *buf, size_t size)
176 {
177 unsigned int cpu=dev->id;
178 int ret;
179
180 #ifdef ERR_INJ_DEBUG
181 printk("write err_data_buffer=[%llx,%llx,%llx] on cpu%d\n",
182 err_data_buffer[cpu].data1,
183 err_data_buffer[cpu].data2,
184 err_data_buffer[cpu].data3,
185 cpu);
186 #endif
187 ret = sscanf(buf, "%llx, %llx, %llx",
188 &err_data_buffer[cpu].data1,
189 &err_data_buffer[cpu].data2,
190 &err_data_buffer[cpu].data3);
191 if (ret!=ERR_DATA_BUFFER_SIZE)
192 return -EINVAL;
193
194 return size;
195 }
196
197 show(status)
198 show(capabilities)
199 show(resources)
200
201 define_one_rw(call_start);
202 define_one_rw(err_type_info);
203 define_one_rw(err_struct_info);
204 define_one_rw(err_data_buffer);
205 define_one_rw(virtual_to_phys);
206 define_one_ro(status);
207 define_one_ro(capabilities);
208 define_one_ro(resources);
209
210 static struct attribute *default_attrs[] = {
211 &dev_attr_call_start.attr,
212 &dev_attr_virtual_to_phys.attr,
213 &dev_attr_err_type_info.attr,
214 &dev_attr_err_struct_info.attr,
215 &dev_attr_err_data_buffer.attr,
216 &dev_attr_status.attr,
217 &dev_attr_capabilities.attr,
218 &dev_attr_resources.attr,
219 NULL
220 };
221
222 static struct attribute_group err_inject_attr_group = {
223 .attrs = default_attrs,
224 .name = "err_inject"
225 };
226 /* Add/Remove err_inject interface for CPU device */
err_inject_add_dev(unsigned int cpu)227 static int err_inject_add_dev(unsigned int cpu)
228 {
229 struct device *sys_dev = get_cpu_device(cpu);
230
231 return sysfs_create_group(&sys_dev->kobj, &err_inject_attr_group);
232 }
233
err_inject_remove_dev(unsigned int cpu)234 static int err_inject_remove_dev(unsigned int cpu)
235 {
236 struct device *sys_dev = get_cpu_device(cpu);
237
238 sysfs_remove_group(&sys_dev->kobj, &err_inject_attr_group);
239 return 0;
240 }
241
242 static enum cpuhp_state hp_online;
243
err_inject_init(void)244 static int __init err_inject_init(void)
245 {
246 int ret;
247 #ifdef ERR_INJ_DEBUG
248 printk(KERN_INFO "Enter error injection driver.\n");
249 #endif
250
251 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "ia64/err_inj:online",
252 err_inject_add_dev, err_inject_remove_dev);
253 if (ret >= 0) {
254 hp_online = ret;
255 ret = 0;
256 }
257 return ret;
258 }
259
err_inject_exit(void)260 static void __exit err_inject_exit(void)
261 {
262 #ifdef ERR_INJ_DEBUG
263 printk(KERN_INFO "Exit error injection driver.\n");
264 #endif
265 cpuhp_remove_state(hp_online);
266 }
267
268 module_init(err_inject_init);
269 module_exit(err_inject_exit);
270
271 MODULE_AUTHOR("Fenghua Yu <fenghua.yu@intel.com>");
272 MODULE_DESCRIPTION("MC error injection kernel sysfs interface");
273 MODULE_LICENSE("GPL");
274