1 /*
2 * Support for Partition Mobility/Migration
3 *
4 * Copyright (C) 2010 Nathan Fontenot
5 * Copyright (C) 2010 IBM Corporation
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation.
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/kobject.h>
14 #include <linux/smp.h>
15 #include <linux/stat.h>
16 #include <linux/completion.h>
17 #include <linux/device.h>
18 #include <linux/delay.h>
19 #include <linux/slab.h>
20
21 #include <asm/machdep.h>
22 #include <asm/rtas.h>
23 #include "pseries.h"
24
25 static struct kobject *mobility_kobj;
26
27 struct update_props_workarea {
28 __be32 phandle;
29 __be32 state;
30 __be64 reserved;
31 __be32 nprops;
32 } __packed;
33
34 #define NODE_ACTION_MASK 0xff000000
35 #define NODE_COUNT_MASK 0x00ffffff
36
37 #define DELETE_DT_NODE 0x01000000
38 #define UPDATE_DT_NODE 0x02000000
39 #define ADD_DT_NODE 0x03000000
40
41 #define MIGRATION_SCOPE (1)
42
mobility_rtas_call(int token,char * buf,s32 scope)43 static int mobility_rtas_call(int token, char *buf, s32 scope)
44 {
45 int rc;
46
47 spin_lock(&rtas_data_buf_lock);
48
49 memcpy(rtas_data_buf, buf, RTAS_DATA_BUF_SIZE);
50 rc = rtas_call(token, 2, 1, NULL, rtas_data_buf, scope);
51 memcpy(buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
52
53 spin_unlock(&rtas_data_buf_lock);
54 return rc;
55 }
56
delete_dt_node(__be32 phandle)57 static int delete_dt_node(__be32 phandle)
58 {
59 struct device_node *dn;
60
61 dn = of_find_node_by_phandle(be32_to_cpu(phandle));
62 if (!dn)
63 return -ENOENT;
64
65 dlpar_detach_node(dn);
66 of_node_put(dn);
67 return 0;
68 }
69
update_dt_property(struct device_node * dn,struct property ** prop,const char * name,u32 vd,char * value)70 static int update_dt_property(struct device_node *dn, struct property **prop,
71 const char *name, u32 vd, char *value)
72 {
73 struct property *new_prop = *prop;
74 int more = 0;
75
76 /* A negative 'vd' value indicates that only part of the new property
77 * value is contained in the buffer and we need to call
78 * ibm,update-properties again to get the rest of the value.
79 *
80 * A negative value is also the two's compliment of the actual value.
81 */
82 if (vd & 0x80000000) {
83 vd = ~vd + 1;
84 more = 1;
85 }
86
87 if (new_prop) {
88 /* partial property fixup */
89 char *new_data = kzalloc(new_prop->length + vd, GFP_KERNEL);
90 if (!new_data)
91 return -ENOMEM;
92
93 memcpy(new_data, new_prop->value, new_prop->length);
94 memcpy(new_data + new_prop->length, value, vd);
95
96 kfree(new_prop->value);
97 new_prop->value = new_data;
98 new_prop->length += vd;
99 } else {
100 new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
101 if (!new_prop)
102 return -ENOMEM;
103
104 new_prop->name = kstrdup(name, GFP_KERNEL);
105 if (!new_prop->name) {
106 kfree(new_prop);
107 return -ENOMEM;
108 }
109
110 new_prop->length = vd;
111 new_prop->value = kzalloc(new_prop->length, GFP_KERNEL);
112 if (!new_prop->value) {
113 kfree(new_prop->name);
114 kfree(new_prop);
115 return -ENOMEM;
116 }
117
118 memcpy(new_prop->value, value, vd);
119 *prop = new_prop;
120 }
121
122 if (!more) {
123 of_update_property(dn, new_prop);
124 *prop = NULL;
125 }
126
127 return 0;
128 }
129
update_dt_node(__be32 phandle,s32 scope)130 static int update_dt_node(__be32 phandle, s32 scope)
131 {
132 struct update_props_workarea *upwa;
133 struct device_node *dn;
134 struct property *prop = NULL;
135 int i, rc, rtas_rc;
136 char *prop_data;
137 char *rtas_buf;
138 int update_properties_token;
139 u32 nprops;
140 u32 vd;
141
142 update_properties_token = rtas_token("ibm,update-properties");
143 if (update_properties_token == RTAS_UNKNOWN_SERVICE)
144 return -EINVAL;
145
146 rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
147 if (!rtas_buf)
148 return -ENOMEM;
149
150 dn = of_find_node_by_phandle(be32_to_cpu(phandle));
151 if (!dn) {
152 kfree(rtas_buf);
153 return -ENOENT;
154 }
155
156 upwa = (struct update_props_workarea *)&rtas_buf[0];
157 upwa->phandle = phandle;
158
159 do {
160 rtas_rc = mobility_rtas_call(update_properties_token, rtas_buf,
161 scope);
162 if (rtas_rc < 0)
163 break;
164
165 prop_data = rtas_buf + sizeof(*upwa);
166 nprops = be32_to_cpu(upwa->nprops);
167
168 /* On the first call to ibm,update-properties for a node the
169 * the first property value descriptor contains an empty
170 * property name, the property value length encoded as u32,
171 * and the property value is the node path being updated.
172 */
173 if (*prop_data == 0) {
174 prop_data++;
175 vd = be32_to_cpu(*(__be32 *)prop_data);
176 prop_data += vd + sizeof(vd);
177 nprops--;
178 }
179
180 for (i = 0; i < nprops; i++) {
181 char *prop_name;
182
183 prop_name = prop_data;
184 prop_data += strlen(prop_name) + 1;
185 vd = be32_to_cpu(*(__be32 *)prop_data);
186 prop_data += sizeof(vd);
187
188 switch (vd) {
189 case 0x00000000:
190 /* name only property, nothing to do */
191 break;
192
193 case 0x80000000:
194 of_remove_property(dn, of_find_property(dn,
195 prop_name, NULL));
196 prop = NULL;
197 break;
198
199 default:
200 rc = update_dt_property(dn, &prop, prop_name,
201 vd, prop_data);
202 if (rc) {
203 printk(KERN_ERR "Could not update %s"
204 " property\n", prop_name);
205 }
206
207 prop_data += vd;
208 }
209 }
210 } while (rtas_rc == 1);
211
212 of_node_put(dn);
213 kfree(rtas_buf);
214 return 0;
215 }
216
add_dt_node(__be32 parent_phandle,__be32 drc_index)217 static int add_dt_node(__be32 parent_phandle, __be32 drc_index)
218 {
219 struct device_node *dn;
220 struct device_node *parent_dn;
221 int rc;
222
223 parent_dn = of_find_node_by_phandle(be32_to_cpu(parent_phandle));
224 if (!parent_dn)
225 return -ENOENT;
226
227 dn = dlpar_configure_connector(drc_index, parent_dn);
228 if (!dn) {
229 of_node_put(parent_dn);
230 return -ENOENT;
231 }
232
233 rc = dlpar_attach_node(dn);
234 if (rc)
235 dlpar_free_cc_nodes(dn);
236
237 of_node_put(parent_dn);
238 return rc;
239 }
240
pseries_devicetree_update(s32 scope)241 int pseries_devicetree_update(s32 scope)
242 {
243 char *rtas_buf;
244 __be32 *data;
245 int update_nodes_token;
246 int rc;
247
248 update_nodes_token = rtas_token("ibm,update-nodes");
249 if (update_nodes_token == RTAS_UNKNOWN_SERVICE)
250 return -EINVAL;
251
252 rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
253 if (!rtas_buf)
254 return -ENOMEM;
255
256 do {
257 rc = mobility_rtas_call(update_nodes_token, rtas_buf, scope);
258 if (rc && rc != 1)
259 break;
260
261 data = (__be32 *)rtas_buf + 4;
262 while (be32_to_cpu(*data) & NODE_ACTION_MASK) {
263 int i;
264 u32 action = be32_to_cpu(*data) & NODE_ACTION_MASK;
265 u32 node_count = be32_to_cpu(*data) & NODE_COUNT_MASK;
266
267 data++;
268
269 for (i = 0; i < node_count; i++) {
270 __be32 phandle = *data++;
271 __be32 drc_index;
272
273 switch (action) {
274 case DELETE_DT_NODE:
275 delete_dt_node(phandle);
276 break;
277 case UPDATE_DT_NODE:
278 update_dt_node(phandle, scope);
279 break;
280 case ADD_DT_NODE:
281 drc_index = *data++;
282 add_dt_node(phandle, drc_index);
283 break;
284 }
285 }
286 }
287 } while (rc == 1);
288
289 kfree(rtas_buf);
290 return rc;
291 }
292
post_mobility_fixup(void)293 void post_mobility_fixup(void)
294 {
295 int rc;
296 int activate_fw_token;
297
298 activate_fw_token = rtas_token("ibm,activate-firmware");
299 if (activate_fw_token == RTAS_UNKNOWN_SERVICE) {
300 printk(KERN_ERR "Could not make post-mobility "
301 "activate-fw call.\n");
302 return;
303 }
304
305 do {
306 rc = rtas_call(activate_fw_token, 0, 1, NULL);
307 } while (rtas_busy_delay(rc));
308
309 if (rc)
310 printk(KERN_ERR "Post-mobility activate-fw failed: %d\n", rc);
311
312 rc = pseries_devicetree_update(MIGRATION_SCOPE);
313 if (rc)
314 printk(KERN_ERR "Post-mobility device tree update "
315 "failed: %d\n", rc);
316
317 return;
318 }
319
migrate_store(struct class * class,struct class_attribute * attr,const char * buf,size_t count)320 static ssize_t migrate_store(struct class *class, struct class_attribute *attr,
321 const char *buf, size_t count)
322 {
323 u64 streamid;
324 int rc;
325
326 rc = kstrtou64(buf, 0, &streamid);
327 if (rc)
328 return rc;
329
330 do {
331 rc = rtas_ibm_suspend_me(streamid);
332 if (rc == -EAGAIN)
333 ssleep(1);
334 } while (rc == -EAGAIN);
335
336 if (rc)
337 return rc;
338
339 post_mobility_fixup();
340 return count;
341 }
342
343 /*
344 * Used by drmgr to determine the kernel behavior of the migration interface.
345 *
346 * Version 1: Performs all PAPR requirements for migration including
347 * firmware activation and device tree update.
348 */
349 #define MIGRATION_API_VERSION 1
350
351 static CLASS_ATTR(migration, S_IWUSR, NULL, migrate_store);
352 static CLASS_ATTR_STRING(api_version, S_IRUGO, __stringify(MIGRATION_API_VERSION));
353
mobility_sysfs_init(void)354 static int __init mobility_sysfs_init(void)
355 {
356 int rc;
357
358 mobility_kobj = kobject_create_and_add("mobility", kernel_kobj);
359 if (!mobility_kobj)
360 return -ENOMEM;
361
362 rc = sysfs_create_file(mobility_kobj, &class_attr_migration.attr);
363 if (rc)
364 pr_err("mobility: unable to create migration sysfs file (%d)\n", rc);
365
366 rc = sysfs_create_file(mobility_kobj, &class_attr_api_version.attr.attr);
367 if (rc)
368 pr_err("mobility: unable to create api_version sysfs file (%d)\n", rc);
369
370 return 0;
371 }
372 machine_device_initcall(pseries, mobility_sysfs_init);
373