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Merge branch 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm
[linux-2.6/next.git] / arch / powerpc / platforms / pseries / dlpar.c
blob227c1c3d585e028874cc895afc3241afff0b3caf
1 /*
2 * Support for dynamic reconfiguration for PCI, Memory, and CPU
3 * Hotplug and Dynamic Logical Partitioning on RPA platforms.
4 *
5 * Copyright (C) 2009 Nathan Fontenot
6 * Copyright (C) 2009 IBM Corporation
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License version
10 * 2 as published by the Free Software Foundation.
11 */
12
13 #include <linux/kernel.h>
14 #include <linux/kref.h>
15 #include <linux/notifier.h>
16 #include <linux/proc_fs.h>
17 #include <linux/spinlock.h>
18 #include <linux/cpu.h>
19 #include <linux/slab.h>
20 #include "offline_states.h"
21
22 #include <asm/prom.h>
23 #include <asm/machdep.h>
24 #include <asm/uaccess.h>
25 #include <asm/rtas.h>
26 #include <asm/pSeries_reconfig.h>
27
28 struct cc_workarea {
29 u32 drc_index;
30 u32 zero;
31 u32 name_offset;
32 u32 prop_length;
33 u32 prop_offset;
34 };
35
36 static void dlpar_free_cc_property(struct property *prop)
37 {
38 kfree(prop->name);
39 kfree(prop->value);
40 kfree(prop);
41 }
42
43 static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa)
44 {
45 struct property *prop;
46 char *name;
47 char *value;
48
49 prop = kzalloc(sizeof(*prop), GFP_KERNEL);
50 if (!prop)
51 return NULL;
52
53 name = (char *)ccwa + ccwa->name_offset;
54 prop->name = kstrdup(name, GFP_KERNEL);
55
56 prop->length = ccwa->prop_length;
57 value = (char *)ccwa + ccwa->prop_offset;
58 prop->value = kzalloc(prop->length, GFP_KERNEL);
59 if (!prop->value) {
60 dlpar_free_cc_property(prop);
61 return NULL;
62 }
63
64 memcpy(prop->value, value, prop->length);
65 return prop;
66 }
67
68 static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa)
69 {
70 struct device_node *dn;
71 char *name;
72
73 dn = kzalloc(sizeof(*dn), GFP_KERNEL);
74 if (!dn)
75 return NULL;
76
77 /* The configure connector reported name does not contain a
78 * preceeding '/', so we allocate a buffer large enough to
79 * prepend this to the full_name.
80 */
81 name = (char *)ccwa + ccwa->name_offset;
82 dn->full_name = kasprintf(GFP_KERNEL, "/%s", name);
83 if (!dn->full_name) {
84 kfree(dn);
85 return NULL;
86 }
87
88 return dn;
89 }
90
91 static void dlpar_free_one_cc_node(struct device_node *dn)
92 {
93 struct property *prop;
94
95 while (dn->properties) {
96 prop = dn->properties;
97 dn->properties = prop->next;
98 dlpar_free_cc_property(prop);
99 }
100
101 kfree(dn->full_name);
102 kfree(dn);
103 }
104
105 static void dlpar_free_cc_nodes(struct device_node *dn)
106 {
107 if (dn->child)
108 dlpar_free_cc_nodes(dn->child);
109
110 if (dn->sibling)
111 dlpar_free_cc_nodes(dn->sibling);
112
113 dlpar_free_one_cc_node(dn);
114 }
115
116 #define NEXT_SIBLING 1
117 #define NEXT_CHILD 2
118 #define NEXT_PROPERTY 3
119 #define PREV_PARENT 4
120 #define MORE_MEMORY 5
121 #define CALL_AGAIN -2
122 #define ERR_CFG_USE -9003
123
124 struct device_node *dlpar_configure_connector(u32 drc_index)
125 {
126 struct device_node *dn;
127 struct device_node *first_dn = NULL;
128 struct device_node *last_dn = NULL;
129 struct property *property;
130 struct property *last_property = NULL;
131 struct cc_workarea *ccwa;
132 int cc_token;
133 int rc;
134
135 cc_token = rtas_token("ibm,configure-connector");
136 if (cc_token == RTAS_UNKNOWN_SERVICE)
137 return NULL;
138
139 spin_lock(&rtas_data_buf_lock);
140 ccwa = (struct cc_workarea *)&rtas_data_buf[0];
141 ccwa->drc_index = drc_index;
142 ccwa->zero = 0;
143
144 rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
145 while (rc) {
146 switch (rc) {
147 case NEXT_SIBLING:
148 dn = dlpar_parse_cc_node(ccwa);
149 if (!dn)
150 goto cc_error;
151
152 dn->parent = last_dn->parent;
153 last_dn->sibling = dn;
154 last_dn = dn;
155 break;
156
157 case NEXT_CHILD:
158 dn = dlpar_parse_cc_node(ccwa);
159 if (!dn)
160 goto cc_error;
161
162 if (!first_dn)
163 first_dn = dn;
164 else {
165 dn->parent = last_dn;
166 if (last_dn)
167 last_dn->child = dn;
168 }
169
170 last_dn = dn;
171 break;
172
173 case NEXT_PROPERTY:
174 property = dlpar_parse_cc_property(ccwa);
175 if (!property)
176 goto cc_error;
177
178 if (!last_dn->properties)
179 last_dn->properties = property;
180 else
181 last_property->next = property;
182
183 last_property = property;
184 break;
185
186 case PREV_PARENT:
187 last_dn = last_dn->parent;
188 break;
189
190 case CALL_AGAIN:
191 break;
192
193 case MORE_MEMORY:
194 case ERR_CFG_USE:
195 default:
196 printk(KERN_ERR "Unexpected Error (%d) "
197 "returned from configure-connector\n", rc);
198 goto cc_error;
199 }
200
201 rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
202 }
203
204 spin_unlock(&rtas_data_buf_lock);
205 return first_dn;
206
207 cc_error:
208 if (first_dn)
209 dlpar_free_cc_nodes(first_dn);
210 spin_unlock(&rtas_data_buf_lock);
211 return NULL;
212 }
213
214 static struct device_node *derive_parent(const char *path)
215 {
216 struct device_node *parent;
217 char *last_slash;
218
219 last_slash = strrchr(path, '/');
220 if (last_slash == path) {
221 parent = of_find_node_by_path("/");
222 } else {
223 char *parent_path;
224 int parent_path_len = last_slash - path + 1;
225 parent_path = kmalloc(parent_path_len, GFP_KERNEL);
226 if (!parent_path)
227 return NULL;
228
229 strlcpy(parent_path, path, parent_path_len);
230 parent = of_find_node_by_path(parent_path);
231 kfree(parent_path);
232 }
233
234 return parent;
235 }
236
237 int dlpar_attach_node(struct device_node *dn)
238 {
239 #ifdef CONFIG_PROC_DEVICETREE
240 struct proc_dir_entry *ent;
241 #endif
242 int rc;
243
244 of_node_set_flag(dn, OF_DYNAMIC);
245 kref_init(&dn->kref);
246 dn->parent = derive_parent(dn->full_name);
247 if (!dn->parent)
248 return -ENOMEM;
249
250 rc = blocking_notifier_call_chain(&pSeries_reconfig_chain,
251 PSERIES_RECONFIG_ADD, dn);
252 if (rc == NOTIFY_BAD) {
253 printk(KERN_ERR "Failed to add device node %s\n",
254 dn->full_name);
255 return -ENOMEM; /* For now, safe to assume kmalloc failure */
256 }
257
258 of_attach_node(dn);
259
260 #ifdef CONFIG_PROC_DEVICETREE
261 ent = proc_mkdir(strrchr(dn->full_name, '/') + 1, dn->parent->pde);
262 if (ent)
263 proc_device_tree_add_node(dn, ent);
264 #endif
265
266 of_node_put(dn->parent);
267 return 0;
268 }
269
270 int dlpar_detach_node(struct device_node *dn)
271 {
272 #ifdef CONFIG_PROC_DEVICETREE
273 struct device_node *parent = dn->parent;
274 struct property *prop = dn->properties;
275
276 while (prop) {
277 remove_proc_entry(prop->name, dn->pde);
278 prop = prop->next;
279 }
280
281 if (dn->pde)
282 remove_proc_entry(dn->pde->name, parent->pde);
283 #endif
284
285 blocking_notifier_call_chain(&pSeries_reconfig_chain,
286 PSERIES_RECONFIG_REMOVE, dn);
287 of_detach_node(dn);
288 of_node_put(dn); /* Must decrement the refcount */
289
290 return 0;
291 }
292
293 #define DR_ENTITY_SENSE 9003
294 #define DR_ENTITY_PRESENT 1
295 #define DR_ENTITY_UNUSABLE 2
296 #define ALLOCATION_STATE 9003
297 #define ALLOC_UNUSABLE 0
298 #define ALLOC_USABLE 1
299 #define ISOLATION_STATE 9001
300 #define ISOLATE 0
301 #define UNISOLATE 1
302
303 int dlpar_acquire_drc(u32 drc_index)
304 {
305 int dr_status, rc;
306
307 rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
308 DR_ENTITY_SENSE, drc_index);
309 if (rc || dr_status != DR_ENTITY_UNUSABLE)
310 return -1;
311
312 rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE);
313 if (rc)
314 return rc;
315
316 rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
317 if (rc) {
318 rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
319 return rc;
320 }
321
322 return 0;
323 }
324
325 int dlpar_release_drc(u32 drc_index)
326 {
327 int dr_status, rc;
328
329 rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
330 DR_ENTITY_SENSE, drc_index);
331 if (rc || dr_status != DR_ENTITY_PRESENT)
332 return -1;
333
334 rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);
335 if (rc)
336 return rc;
337
338 rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
339 if (rc) {
340 rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
341 return rc;
342 }
343
344 return 0;
345 }
346
347 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
348
349 static int dlpar_online_cpu(struct device_node *dn)
350 {
351 int rc = 0;
352 unsigned int cpu;
353 int len, nthreads, i;
354 const u32 *intserv;
355
356 intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
357 if (!intserv)
358 return -EINVAL;
359
360 nthreads = len / sizeof(u32);
361
362 cpu_maps_update_begin();
363 for (i = 0; i < nthreads; i++) {
364 for_each_present_cpu(cpu) {
365 if (get_hard_smp_processor_id(cpu) != intserv[i])
366 continue;
367 BUG_ON(get_cpu_current_state(cpu)
368 != CPU_STATE_OFFLINE);
369 cpu_maps_update_done();
370 rc = cpu_up(cpu);
371 if (rc)
372 goto out;
373 cpu_maps_update_begin();
374
375 break;
376 }
377 if (cpu == num_possible_cpus())
378 printk(KERN_WARNING "Could not find cpu to online "
379 "with physical id 0x%x\n", intserv[i]);
380 }
381 cpu_maps_update_done();
382
383 out:
384 return rc;
385
386 }
387
388 static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
389 {
390 struct device_node *dn;
391 unsigned long drc_index;
392 char *cpu_name;
393 int rc;
394
395 cpu_hotplug_driver_lock();
396 rc = strict_strtoul(buf, 0, &drc_index);
397 if (rc) {
398 rc = -EINVAL;
399 goto out;
400 }
401
402 dn = dlpar_configure_connector(drc_index);
403 if (!dn) {
404 rc = -EINVAL;
405 goto out;
406 }
407
408 /* configure-connector reports cpus as living in the base
409 * directory of the device tree. CPUs actually live in the
410 * cpus directory so we need to fixup the full_name.
411 */
412 cpu_name = kasprintf(GFP_KERNEL, "/cpus%s", dn->full_name);
413 if (!cpu_name) {
414 dlpar_free_cc_nodes(dn);
415 rc = -ENOMEM;
416 goto out;
417 }
418
419 kfree(dn->full_name);
420 dn->full_name = cpu_name;
421
422 rc = dlpar_acquire_drc(drc_index);
423 if (rc) {
424 dlpar_free_cc_nodes(dn);
425 rc = -EINVAL;
426 goto out;
427 }
428
429 rc = dlpar_attach_node(dn);
430 if (rc) {
431 dlpar_release_drc(drc_index);
432 dlpar_free_cc_nodes(dn);
433 goto out;
434 }
435
436 rc = dlpar_online_cpu(dn);
437 out:
438 cpu_hotplug_driver_unlock();
439
440 return rc ? rc : count;
441 }
442
443 static int dlpar_offline_cpu(struct device_node *dn)
444 {
445 int rc = 0;
446 unsigned int cpu;
447 int len, nthreads, i;
448 const u32 *intserv;
449
450 intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
451 if (!intserv)
452 return -EINVAL;
453
454 nthreads = len / sizeof(u32);
455
456 cpu_maps_update_begin();
457 for (i = 0; i < nthreads; i++) {
458 for_each_present_cpu(cpu) {
459 if (get_hard_smp_processor_id(cpu) != intserv[i])
460 continue;
461
462 if (get_cpu_current_state(cpu) == CPU_STATE_OFFLINE)
463 break;
464
465 if (get_cpu_current_state(cpu) == CPU_STATE_ONLINE) {
466 set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
467 cpu_maps_update_done();
468 rc = cpu_down(cpu);
469 if (rc)
470 goto out;
471 cpu_maps_update_begin();
472 break;
473
474 }
475
476 /*
477 * The cpu is in CPU_STATE_INACTIVE.
478 * Upgrade it's state to CPU_STATE_OFFLINE.
479 */
480 set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
481 BUG_ON(plpar_hcall_norets(H_PROD, intserv[i])
482 != H_SUCCESS);
483 __cpu_die(cpu);
484 break;
485 }
486 if (cpu == num_possible_cpus())
487 printk(KERN_WARNING "Could not find cpu to offline "
488 "with physical id 0x%x\n", intserv[i]);
489 }
490 cpu_maps_update_done();
491
492 out:
493 return rc;
494
495 }
496
497 static ssize_t dlpar_cpu_release(const char *buf, size_t count)
498 {
499 struct device_node *dn;
500 const u32 *drc_index;
501 int rc;
502
503 dn = of_find_node_by_path(buf);
504 if (!dn)
505 return -EINVAL;
506
507 drc_index = of_get_property(dn, "ibm,my-drc-index", NULL);
508 if (!drc_index) {
509 of_node_put(dn);
510 return -EINVAL;
511 }
512
513 cpu_hotplug_driver_lock();
514 rc = dlpar_offline_cpu(dn);
515 if (rc) {
516 of_node_put(dn);
517 rc = -EINVAL;
518 goto out;
519 }
520
521 rc = dlpar_release_drc(*drc_index);
522 if (rc) {
523 of_node_put(dn);
524 goto out;
525 }
526
527 rc = dlpar_detach_node(dn);
528 if (rc) {
529 dlpar_acquire_drc(*drc_index);
530 goto out;
531 }
532
533 of_node_put(dn);
534 out:
535 cpu_hotplug_driver_unlock();
536 return rc ? rc : count;
537 }
538
539 static int __init pseries_dlpar_init(void)
540 {
541 ppc_md.cpu_probe = dlpar_cpu_probe;
542 ppc_md.cpu_release = dlpar_cpu_release;
543
544 return 0;
545 }
546 machine_device_initcall(pseries, pseries_dlpar_init);
547
548 #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
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