Merge branch 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git...
[cascardo/linux.git] / arch / powerpc / platforms / pseries / dlpar.c
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 #define pr_fmt(fmt)     "dlpar: " fmt
14
15 #include <linux/kernel.h>
16 #include <linux/notifier.h>
17 #include <linux/spinlock.h>
18 #include <linux/cpu.h>
19 #include <linux/slab.h>
20 #include <linux/of.h>
21
22 #include "of_helpers.h"
23 #include "pseries.h"
24
25 #include <asm/prom.h>
26 #include <asm/machdep.h>
27 #include <asm/uaccess.h>
28 #include <asm/rtas.h>
29
30 struct workqueue_struct *pseries_hp_wq;
31
32 struct pseries_hp_work {
33         struct work_struct work;
34         struct pseries_hp_errorlog *errlog;
35         struct completion *hp_completion;
36         int *rc;
37 };
38
39 struct cc_workarea {
40         __be32  drc_index;
41         __be32  zero;
42         __be32  name_offset;
43         __be32  prop_length;
44         __be32  prop_offset;
45 };
46
47 void dlpar_free_cc_property(struct property *prop)
48 {
49         kfree(prop->name);
50         kfree(prop->value);
51         kfree(prop);
52 }
53
54 static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa)
55 {
56         struct property *prop;
57         char *name;
58         char *value;
59
60         prop = kzalloc(sizeof(*prop), GFP_KERNEL);
61         if (!prop)
62                 return NULL;
63
64         name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
65         prop->name = kstrdup(name, GFP_KERNEL);
66
67         prop->length = be32_to_cpu(ccwa->prop_length);
68         value = (char *)ccwa + be32_to_cpu(ccwa->prop_offset);
69         prop->value = kmemdup(value, prop->length, GFP_KERNEL);
70         if (!prop->value) {
71                 dlpar_free_cc_property(prop);
72                 return NULL;
73         }
74
75         return prop;
76 }
77
78 static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa,
79                                                const char *path)
80 {
81         struct device_node *dn;
82         char *name;
83
84         /* If parent node path is "/" advance path to NULL terminator to
85          * prevent double leading slashs in full_name.
86          */
87         if (!path[1])
88                 path++;
89
90         dn = kzalloc(sizeof(*dn), GFP_KERNEL);
91         if (!dn)
92                 return NULL;
93
94         name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
95         dn->full_name = kasprintf(GFP_KERNEL, "%s/%s", path, name);
96         if (!dn->full_name) {
97                 kfree(dn);
98                 return NULL;
99         }
100
101         of_node_set_flag(dn, OF_DYNAMIC);
102         of_node_init(dn);
103
104         return dn;
105 }
106
107 static void dlpar_free_one_cc_node(struct device_node *dn)
108 {
109         struct property *prop;
110
111         while (dn->properties) {
112                 prop = dn->properties;
113                 dn->properties = prop->next;
114                 dlpar_free_cc_property(prop);
115         }
116
117         kfree(dn->full_name);
118         kfree(dn);
119 }
120
121 void dlpar_free_cc_nodes(struct device_node *dn)
122 {
123         if (dn->child)
124                 dlpar_free_cc_nodes(dn->child);
125
126         if (dn->sibling)
127                 dlpar_free_cc_nodes(dn->sibling);
128
129         dlpar_free_one_cc_node(dn);
130 }
131
132 #define COMPLETE        0
133 #define NEXT_SIBLING    1
134 #define NEXT_CHILD      2
135 #define NEXT_PROPERTY   3
136 #define PREV_PARENT     4
137 #define MORE_MEMORY     5
138 #define CALL_AGAIN      -2
139 #define ERR_CFG_USE     -9003
140
141 struct device_node *dlpar_configure_connector(__be32 drc_index,
142                                               struct device_node *parent)
143 {
144         struct device_node *dn;
145         struct device_node *first_dn = NULL;
146         struct device_node *last_dn = NULL;
147         struct property *property;
148         struct property *last_property = NULL;
149         struct cc_workarea *ccwa;
150         char *data_buf;
151         const char *parent_path = parent->full_name;
152         int cc_token;
153         int rc = -1;
154
155         cc_token = rtas_token("ibm,configure-connector");
156         if (cc_token == RTAS_UNKNOWN_SERVICE)
157                 return NULL;
158
159         data_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
160         if (!data_buf)
161                 return NULL;
162
163         ccwa = (struct cc_workarea *)&data_buf[0];
164         ccwa->drc_index = drc_index;
165         ccwa->zero = 0;
166
167         do {
168                 /* Since we release the rtas_data_buf lock between configure
169                  * connector calls we want to re-populate the rtas_data_buffer
170                  * with the contents of the previous call.
171                  */
172                 spin_lock(&rtas_data_buf_lock);
173
174                 memcpy(rtas_data_buf, data_buf, RTAS_DATA_BUF_SIZE);
175                 rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
176                 memcpy(data_buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
177
178                 spin_unlock(&rtas_data_buf_lock);
179
180                 switch (rc) {
181                 case COMPLETE:
182                         break;
183
184                 case NEXT_SIBLING:
185                         dn = dlpar_parse_cc_node(ccwa, parent_path);
186                         if (!dn)
187                                 goto cc_error;
188
189                         dn->parent = last_dn->parent;
190                         last_dn->sibling = dn;
191                         last_dn = dn;
192                         break;
193
194                 case NEXT_CHILD:
195                         if (first_dn)
196                                 parent_path = last_dn->full_name;
197
198                         dn = dlpar_parse_cc_node(ccwa, parent_path);
199                         if (!dn)
200                                 goto cc_error;
201
202                         if (!first_dn) {
203                                 dn->parent = parent;
204                                 first_dn = dn;
205                         } else {
206                                 dn->parent = last_dn;
207                                 if (last_dn)
208                                         last_dn->child = dn;
209                         }
210
211                         last_dn = dn;
212                         break;
213
214                 case NEXT_PROPERTY:
215                         property = dlpar_parse_cc_property(ccwa);
216                         if (!property)
217                                 goto cc_error;
218
219                         if (!last_dn->properties)
220                                 last_dn->properties = property;
221                         else
222                                 last_property->next = property;
223
224                         last_property = property;
225                         break;
226
227                 case PREV_PARENT:
228                         last_dn = last_dn->parent;
229                         parent_path = last_dn->parent->full_name;
230                         break;
231
232                 case CALL_AGAIN:
233                         break;
234
235                 case MORE_MEMORY:
236                 case ERR_CFG_USE:
237                 default:
238                         printk(KERN_ERR "Unexpected Error (%d) "
239                                "returned from configure-connector\n", rc);
240                         goto cc_error;
241                 }
242         } while (rc);
243
244 cc_error:
245         kfree(data_buf);
246
247         if (rc) {
248                 if (first_dn)
249                         dlpar_free_cc_nodes(first_dn);
250
251                 return NULL;
252         }
253
254         return first_dn;
255 }
256
257 int dlpar_attach_node(struct device_node *dn)
258 {
259         int rc;
260
261         dn->parent = pseries_of_derive_parent(dn->full_name);
262         if (IS_ERR(dn->parent))
263                 return PTR_ERR(dn->parent);
264
265         rc = of_attach_node(dn);
266         if (rc) {
267                 printk(KERN_ERR "Failed to add device node %s\n",
268                        dn->full_name);
269                 return rc;
270         }
271
272         of_node_put(dn->parent);
273         return 0;
274 }
275
276 int dlpar_detach_node(struct device_node *dn)
277 {
278         struct device_node *child;
279         int rc;
280
281         child = of_get_next_child(dn, NULL);
282         while (child) {
283                 dlpar_detach_node(child);
284                 child = of_get_next_child(dn, child);
285         }
286
287         rc = of_detach_node(dn);
288         if (rc)
289                 return rc;
290
291         of_node_put(dn); /* Must decrement the refcount */
292         return 0;
293 }
294
295 #define DR_ENTITY_SENSE         9003
296 #define DR_ENTITY_PRESENT       1
297 #define DR_ENTITY_UNUSABLE      2
298 #define ALLOCATION_STATE        9003
299 #define ALLOC_UNUSABLE          0
300 #define ALLOC_USABLE            1
301 #define ISOLATION_STATE         9001
302 #define ISOLATE                 0
303 #define UNISOLATE               1
304
305 int dlpar_acquire_drc(u32 drc_index)
306 {
307         int dr_status, rc;
308
309         rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
310                        DR_ENTITY_SENSE, drc_index);
311         if (rc || dr_status != DR_ENTITY_UNUSABLE)
312                 return -1;
313
314         rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE);
315         if (rc)
316                 return rc;
317
318         rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
319         if (rc) {
320                 rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
321                 return rc;
322         }
323
324         return 0;
325 }
326
327 int dlpar_release_drc(u32 drc_index)
328 {
329         int dr_status, rc;
330
331         rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
332                        DR_ENTITY_SENSE, drc_index);
333         if (rc || dr_status != DR_ENTITY_PRESENT)
334                 return -1;
335
336         rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);
337         if (rc)
338                 return rc;
339
340         rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
341         if (rc) {
342                 rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
343                 return rc;
344         }
345
346         return 0;
347 }
348
349 static int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
350 {
351         int rc;
352
353         /* pseries error logs are in BE format, convert to cpu type */
354         switch (hp_elog->id_type) {
355         case PSERIES_HP_ELOG_ID_DRC_COUNT:
356                 hp_elog->_drc_u.drc_count =
357                                         be32_to_cpu(hp_elog->_drc_u.drc_count);
358                 break;
359         case PSERIES_HP_ELOG_ID_DRC_INDEX:
360                 hp_elog->_drc_u.drc_index =
361                                         be32_to_cpu(hp_elog->_drc_u.drc_index);
362         }
363
364         switch (hp_elog->resource) {
365         case PSERIES_HP_ELOG_RESOURCE_MEM:
366                 rc = dlpar_memory(hp_elog);
367                 break;
368         case PSERIES_HP_ELOG_RESOURCE_CPU:
369                 rc = dlpar_cpu(hp_elog);
370                 break;
371         default:
372                 pr_warn_ratelimited("Invalid resource (%d) specified\n",
373                                     hp_elog->resource);
374                 rc = -EINVAL;
375         }
376
377         return rc;
378 }
379
380 void pseries_hp_work_fn(struct work_struct *work)
381 {
382         struct pseries_hp_work *hp_work =
383                         container_of(work, struct pseries_hp_work, work);
384
385         if (hp_work->rc)
386                 *(hp_work->rc) = handle_dlpar_errorlog(hp_work->errlog);
387         else
388                 handle_dlpar_errorlog(hp_work->errlog);
389
390         if (hp_work->hp_completion)
391                 complete(hp_work->hp_completion);
392
393         kfree(hp_work->errlog);
394         kfree((void *)work);
395 }
396
397 void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog,
398                          struct completion *hotplug_done, int *rc)
399 {
400         struct pseries_hp_work *work;
401         struct pseries_hp_errorlog *hp_errlog_copy;
402
403         hp_errlog_copy = kmalloc(sizeof(struct pseries_hp_errorlog),
404                                  GFP_KERNEL);
405         memcpy(hp_errlog_copy, hp_errlog, sizeof(struct pseries_hp_errorlog));
406
407         work = kmalloc(sizeof(struct pseries_hp_work), GFP_KERNEL);
408         if (work) {
409                 INIT_WORK((struct work_struct *)work, pseries_hp_work_fn);
410                 work->errlog = hp_errlog_copy;
411                 work->hp_completion = hotplug_done;
412                 work->rc = rc;
413                 queue_work(pseries_hp_wq, (struct work_struct *)work);
414         } else {
415                 *rc = -ENOMEM;
416                 complete(hotplug_done);
417         }
418 }
419
420 static ssize_t dlpar_store(struct class *class, struct class_attribute *attr,
421                            const char *buf, size_t count)
422 {
423         struct pseries_hp_errorlog *hp_elog;
424         struct completion hotplug_done;
425         const char *arg;
426         int rc;
427
428         hp_elog = kzalloc(sizeof(*hp_elog), GFP_KERNEL);
429         if (!hp_elog) {
430                 rc = -ENOMEM;
431                 goto dlpar_store_out;
432         }
433
434         /* Parse out the request from the user, this will be in the form
435          * <resource> <action> <id_type> <id>
436          */
437         arg = buf;
438         if (!strncmp(arg, "memory", 6)) {
439                 hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_MEM;
440                 arg += strlen("memory ");
441         } else if (!strncmp(arg, "cpu", 3)) {
442                 hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_CPU;
443                 arg += strlen("cpu ");
444         } else {
445                 pr_err("Invalid resource specified: \"%s\"\n", buf);
446                 rc = -EINVAL;
447                 goto dlpar_store_out;
448         }
449
450         if (!strncmp(arg, "add", 3)) {
451                 hp_elog->action = PSERIES_HP_ELOG_ACTION_ADD;
452                 arg += strlen("add ");
453         } else if (!strncmp(arg, "remove", 6)) {
454                 hp_elog->action = PSERIES_HP_ELOG_ACTION_REMOVE;
455                 arg += strlen("remove ");
456         } else {
457                 pr_err("Invalid action specified: \"%s\"\n", buf);
458                 rc = -EINVAL;
459                 goto dlpar_store_out;
460         }
461
462         if (!strncmp(arg, "index", 5)) {
463                 u32 index;
464
465                 hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
466                 arg += strlen("index ");
467                 if (kstrtou32(arg, 0, &index)) {
468                         rc = -EINVAL;
469                         pr_err("Invalid drc_index specified: \"%s\"\n", buf);
470                         goto dlpar_store_out;
471                 }
472
473                 hp_elog->_drc_u.drc_index = cpu_to_be32(index);
474         } else if (!strncmp(arg, "count", 5)) {
475                 u32 count;
476
477                 hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_COUNT;
478                 arg += strlen("count ");
479                 if (kstrtou32(arg, 0, &count)) {
480                         rc = -EINVAL;
481                         pr_err("Invalid count specified: \"%s\"\n", buf);
482                         goto dlpar_store_out;
483                 }
484
485                 hp_elog->_drc_u.drc_count = cpu_to_be32(count);
486         } else {
487                 pr_err("Invalid id_type specified: \"%s\"\n", buf);
488                 rc = -EINVAL;
489                 goto dlpar_store_out;
490         }
491
492         init_completion(&hotplug_done);
493         queue_hotplug_event(hp_elog, &hotplug_done, &rc);
494         wait_for_completion(&hotplug_done);
495
496 dlpar_store_out:
497         kfree(hp_elog);
498         return rc ? rc : count;
499 }
500
501 static CLASS_ATTR(dlpar, S_IWUSR, NULL, dlpar_store);
502
503 static int __init pseries_dlpar_init(void)
504 {
505         pseries_hp_wq = alloc_workqueue("pseries hotplug workqueue",
506                                         WQ_UNBOUND, 1);
507         return sysfs_create_file(kernel_kobj, &class_attr_dlpar.attr);
508 }
509 machine_device_initcall(pseries, pseries_dlpar_init);
510