Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux...
[sfrench/cifs-2.6.git] / arch / powerpc / platforms / pseries / hotplug-memory.c
1 /*
2  * pseries Memory Hotplug infrastructure.
3  *
4  * Copyright (C) 2008 Badari Pulavarty, IBM Corporation
5  *
6  *      This program is free software; you can redistribute it and/or
7  *      modify it under the terms of the GNU General Public License
8  *      as published by the Free Software Foundation; either version
9  *      2 of the License, or (at your option) any later version.
10  */
11
12 #define pr_fmt(fmt)     "pseries-hotplug-mem: " fmt
13
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 #include <linux/memblock.h>
17 #include <linux/memory.h>
18 #include <linux/memory_hotplug.h>
19 #include <linux/slab.h>
20
21 #include <asm/firmware.h>
22 #include <asm/machdep.h>
23 #include <asm/prom.h>
24 #include <asm/sparsemem.h>
25 #include "pseries.h"
26
27 static bool rtas_hp_event;
28
29 unsigned long pseries_memory_block_size(void)
30 {
31         struct device_node *np;
32         unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
33         struct resource r;
34
35         np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
36         if (np) {
37                 const __be64 *size;
38
39                 size = of_get_property(np, "ibm,lmb-size", NULL);
40                 if (size)
41                         memblock_size = be64_to_cpup(size);
42                 of_node_put(np);
43         } else  if (machine_is(pseries)) {
44                 /* This fallback really only applies to pseries */
45                 unsigned int memzero_size = 0;
46
47                 np = of_find_node_by_path("/memory@0");
48                 if (np) {
49                         if (!of_address_to_resource(np, 0, &r))
50                                 memzero_size = resource_size(&r);
51                         of_node_put(np);
52                 }
53
54                 if (memzero_size) {
55                         /* We now know the size of memory@0, use this to find
56                          * the first memoryblock and get its size.
57                          */
58                         char buf[64];
59
60                         sprintf(buf, "/memory@%x", memzero_size);
61                         np = of_find_node_by_path(buf);
62                         if (np) {
63                                 if (!of_address_to_resource(np, 0, &r))
64                                         memblock_size = resource_size(&r);
65                                 of_node_put(np);
66                         }
67                 }
68         }
69         return memblock_size;
70 }
71
72 static void dlpar_free_property(struct property *prop)
73 {
74         kfree(prop->name);
75         kfree(prop->value);
76         kfree(prop);
77 }
78
79 static struct property *dlpar_clone_property(struct property *prop,
80                                              u32 prop_size)
81 {
82         struct property *new_prop;
83
84         new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
85         if (!new_prop)
86                 return NULL;
87
88         new_prop->name = kstrdup(prop->name, GFP_KERNEL);
89         new_prop->value = kzalloc(prop_size, GFP_KERNEL);
90         if (!new_prop->name || !new_prop->value) {
91                 dlpar_free_property(new_prop);
92                 return NULL;
93         }
94
95         memcpy(new_prop->value, prop->value, prop->length);
96         new_prop->length = prop_size;
97
98         of_property_set_flag(new_prop, OF_DYNAMIC);
99         return new_prop;
100 }
101
102 static struct property *dlpar_clone_drconf_property(struct device_node *dn)
103 {
104         struct property *prop, *new_prop;
105         struct of_drconf_cell *lmbs;
106         u32 num_lmbs, *p;
107         int i;
108
109         prop = of_find_property(dn, "ibm,dynamic-memory", NULL);
110         if (!prop)
111                 return NULL;
112
113         new_prop = dlpar_clone_property(prop, prop->length);
114         if (!new_prop)
115                 return NULL;
116
117         /* Convert the property to cpu endian-ness */
118         p = new_prop->value;
119         *p = be32_to_cpu(*p);
120
121         num_lmbs = *p++;
122         lmbs = (struct of_drconf_cell *)p;
123
124         for (i = 0; i < num_lmbs; i++) {
125                 lmbs[i].base_addr = be64_to_cpu(lmbs[i].base_addr);
126                 lmbs[i].drc_index = be32_to_cpu(lmbs[i].drc_index);
127                 lmbs[i].flags = be32_to_cpu(lmbs[i].flags);
128         }
129
130         return new_prop;
131 }
132
133 static void dlpar_update_drconf_property(struct device_node *dn,
134                                          struct property *prop)
135 {
136         struct of_drconf_cell *lmbs;
137         u32 num_lmbs, *p;
138         int i;
139
140         /* Convert the property back to BE */
141         p = prop->value;
142         num_lmbs = *p;
143         *p = cpu_to_be32(*p);
144         p++;
145
146         lmbs = (struct of_drconf_cell *)p;
147         for (i = 0; i < num_lmbs; i++) {
148                 lmbs[i].base_addr = cpu_to_be64(lmbs[i].base_addr);
149                 lmbs[i].drc_index = cpu_to_be32(lmbs[i].drc_index);
150                 lmbs[i].flags = cpu_to_be32(lmbs[i].flags);
151         }
152
153         rtas_hp_event = true;
154         of_update_property(dn, prop);
155         rtas_hp_event = false;
156 }
157
158 static int dlpar_update_device_tree_lmb(struct of_drconf_cell *lmb)
159 {
160         struct device_node *dn;
161         struct property *prop;
162         struct of_drconf_cell *lmbs;
163         u32 *p, num_lmbs;
164         int i;
165
166         dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
167         if (!dn)
168                 return -ENODEV;
169
170         prop = dlpar_clone_drconf_property(dn);
171         if (!prop) {
172                 of_node_put(dn);
173                 return -ENODEV;
174         }
175
176         p = prop->value;
177         num_lmbs = *p++;
178         lmbs = (struct of_drconf_cell *)p;
179
180         for (i = 0; i < num_lmbs; i++) {
181                 if (lmbs[i].drc_index == lmb->drc_index) {
182                         lmbs[i].flags = lmb->flags;
183                         lmbs[i].aa_index = lmb->aa_index;
184
185                         dlpar_update_drconf_property(dn, prop);
186                         break;
187                 }
188         }
189
190         of_node_put(dn);
191         return 0;
192 }
193
194 static u32 find_aa_index(struct device_node *dr_node,
195                          struct property *ala_prop, const u32 *lmb_assoc)
196 {
197         u32 *assoc_arrays;
198         u32 aa_index;
199         int aa_arrays, aa_array_entries, aa_array_sz;
200         int i, index;
201
202         /*
203          * The ibm,associativity-lookup-arrays property is defined to be
204          * a 32-bit value specifying the number of associativity arrays
205          * followed by a 32-bitvalue specifying the number of entries per
206          * array, followed by the associativity arrays.
207          */
208         assoc_arrays = ala_prop->value;
209
210         aa_arrays = be32_to_cpu(assoc_arrays[0]);
211         aa_array_entries = be32_to_cpu(assoc_arrays[1]);
212         aa_array_sz = aa_array_entries * sizeof(u32);
213
214         aa_index = -1;
215         for (i = 0; i < aa_arrays; i++) {
216                 index = (i * aa_array_entries) + 2;
217
218                 if (memcmp(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz))
219                         continue;
220
221                 aa_index = i;
222                 break;
223         }
224
225         if (aa_index == -1) {
226                 struct property *new_prop;
227                 u32 new_prop_size;
228
229                 new_prop_size = ala_prop->length + aa_array_sz;
230                 new_prop = dlpar_clone_property(ala_prop, new_prop_size);
231                 if (!new_prop)
232                         return -1;
233
234                 assoc_arrays = new_prop->value;
235
236                 /* increment the number of entries in the lookup array */
237                 assoc_arrays[0] = cpu_to_be32(aa_arrays + 1);
238
239                 /* copy the new associativity into the lookup array */
240                 index = aa_arrays * aa_array_entries + 2;
241                 memcpy(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz);
242
243                 of_update_property(dr_node, new_prop);
244
245                 /*
246                  * The associativity lookup array index for this lmb is
247                  * number of entries - 1 since we added its associativity
248                  * to the end of the lookup array.
249                  */
250                 aa_index = be32_to_cpu(assoc_arrays[0]) - 1;
251         }
252
253         return aa_index;
254 }
255
256 static u32 lookup_lmb_associativity_index(struct of_drconf_cell *lmb)
257 {
258         struct device_node *parent, *lmb_node, *dr_node;
259         struct property *ala_prop;
260         const u32 *lmb_assoc;
261         u32 aa_index;
262
263         parent = of_find_node_by_path("/");
264         if (!parent)
265                 return -ENODEV;
266
267         lmb_node = dlpar_configure_connector(cpu_to_be32(lmb->drc_index),
268                                              parent);
269         of_node_put(parent);
270         if (!lmb_node)
271                 return -EINVAL;
272
273         lmb_assoc = of_get_property(lmb_node, "ibm,associativity", NULL);
274         if (!lmb_assoc) {
275                 dlpar_free_cc_nodes(lmb_node);
276                 return -ENODEV;
277         }
278
279         dr_node = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
280         if (!dr_node) {
281                 dlpar_free_cc_nodes(lmb_node);
282                 return -ENODEV;
283         }
284
285         ala_prop = of_find_property(dr_node, "ibm,associativity-lookup-arrays",
286                                     NULL);
287         if (!ala_prop) {
288                 of_node_put(dr_node);
289                 dlpar_free_cc_nodes(lmb_node);
290                 return -ENODEV;
291         }
292
293         aa_index = find_aa_index(dr_node, ala_prop, lmb_assoc);
294
295         dlpar_free_cc_nodes(lmb_node);
296         return aa_index;
297 }
298
299 static int dlpar_add_device_tree_lmb(struct of_drconf_cell *lmb)
300 {
301         int aa_index;
302
303         lmb->flags |= DRCONF_MEM_ASSIGNED;
304
305         aa_index = lookup_lmb_associativity_index(lmb);
306         if (aa_index < 0) {
307                 pr_err("Couldn't find associativity index for drc index %x\n",
308                        lmb->drc_index);
309                 return aa_index;
310         }
311
312         lmb->aa_index = aa_index;
313         return dlpar_update_device_tree_lmb(lmb);
314 }
315
316 static int dlpar_remove_device_tree_lmb(struct of_drconf_cell *lmb)
317 {
318         lmb->flags &= ~DRCONF_MEM_ASSIGNED;
319         lmb->aa_index = 0xffffffff;
320         return dlpar_update_device_tree_lmb(lmb);
321 }
322
323 #ifdef CONFIG_MEMORY_HOTREMOVE
324 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
325 {
326         unsigned long block_sz, start_pfn;
327         int sections_per_block;
328         int i, nid;
329
330         start_pfn = base >> PAGE_SHIFT;
331
332         lock_device_hotplug();
333
334         if (!pfn_valid(start_pfn))
335                 goto out;
336
337         block_sz = pseries_memory_block_size();
338         sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
339         nid = memory_add_physaddr_to_nid(base);
340
341         for (i = 0; i < sections_per_block; i++) {
342                 remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
343                 base += MIN_MEMORY_BLOCK_SIZE;
344         }
345
346 out:
347         /* Update memory regions for memory remove */
348         memblock_remove(base, memblock_size);
349         unlock_device_hotplug();
350         return 0;
351 }
352
353 static int pseries_remove_mem_node(struct device_node *np)
354 {
355         const char *type;
356         const __be32 *regs;
357         unsigned long base;
358         unsigned int lmb_size;
359         int ret = -EINVAL;
360
361         /*
362          * Check to see if we are actually removing memory
363          */
364         type = of_get_property(np, "device_type", NULL);
365         if (type == NULL || strcmp(type, "memory") != 0)
366                 return 0;
367
368         /*
369          * Find the base address and size of the memblock
370          */
371         regs = of_get_property(np, "reg", NULL);
372         if (!regs)
373                 return ret;
374
375         base = be64_to_cpu(*(unsigned long *)regs);
376         lmb_size = be32_to_cpu(regs[3]);
377
378         pseries_remove_memblock(base, lmb_size);
379         return 0;
380 }
381
382 static bool lmb_is_removable(struct of_drconf_cell *lmb)
383 {
384         int i, scns_per_block;
385         int rc = 1;
386         unsigned long pfn, block_sz;
387         u64 phys_addr;
388
389         if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
390                 return false;
391
392         block_sz = memory_block_size_bytes();
393         scns_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
394         phys_addr = lmb->base_addr;
395
396         for (i = 0; i < scns_per_block; i++) {
397                 pfn = PFN_DOWN(phys_addr);
398                 if (!pfn_present(pfn))
399                         continue;
400
401                 rc &= is_mem_section_removable(pfn, PAGES_PER_SECTION);
402                 phys_addr += MIN_MEMORY_BLOCK_SIZE;
403         }
404
405         return rc ? true : false;
406 }
407
408 static int dlpar_add_lmb(struct of_drconf_cell *);
409
410 static struct memory_block *lmb_to_memblock(struct of_drconf_cell *lmb)
411 {
412         unsigned long section_nr;
413         struct mem_section *mem_sect;
414         struct memory_block *mem_block;
415
416         section_nr = pfn_to_section_nr(PFN_DOWN(lmb->base_addr));
417         mem_sect = __nr_to_section(section_nr);
418
419         mem_block = find_memory_block(mem_sect);
420         return mem_block;
421 }
422
423 static int dlpar_remove_lmb(struct of_drconf_cell *lmb)
424 {
425         struct memory_block *mem_block;
426         unsigned long block_sz;
427         int nid, rc;
428
429         if (!lmb_is_removable(lmb))
430                 return -EINVAL;
431
432         mem_block = lmb_to_memblock(lmb);
433         if (!mem_block)
434                 return -EINVAL;
435
436         rc = device_offline(&mem_block->dev);
437         put_device(&mem_block->dev);
438         if (rc)
439                 return rc;
440
441         block_sz = pseries_memory_block_size();
442         nid = memory_add_physaddr_to_nid(lmb->base_addr);
443
444         remove_memory(nid, lmb->base_addr, block_sz);
445
446         /* Update memory regions for memory remove */
447         memblock_remove(lmb->base_addr, block_sz);
448
449         dlpar_release_drc(lmb->drc_index);
450         dlpar_remove_device_tree_lmb(lmb);
451
452         return 0;
453 }
454
455 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove,
456                                         struct property *prop)
457 {
458         struct of_drconf_cell *lmbs;
459         int lmbs_removed = 0;
460         int lmbs_available = 0;
461         u32 num_lmbs, *p;
462         int i, rc;
463
464         pr_info("Attempting to hot-remove %d LMB(s)\n", lmbs_to_remove);
465
466         if (lmbs_to_remove == 0)
467                 return -EINVAL;
468
469         p = prop->value;
470         num_lmbs = *p++;
471         lmbs = (struct of_drconf_cell *)p;
472
473         /* Validate that there are enough LMBs to satisfy the request */
474         for (i = 0; i < num_lmbs; i++) {
475                 if (lmb_is_removable(&lmbs[i]))
476                         lmbs_available++;
477         }
478
479         if (lmbs_available < lmbs_to_remove) {
480                 pr_info("Not enough LMBs available (%d of %d) to satisfy request\n",
481                         lmbs_available, lmbs_to_remove);
482                 return -EINVAL;
483         }
484
485         for (i = 0; i < num_lmbs && lmbs_removed < lmbs_to_remove; i++) {
486                 rc = dlpar_remove_lmb(&lmbs[i]);
487                 if (rc)
488                         continue;
489
490                 lmbs_removed++;
491
492                 /* Mark this lmb so we can add it later if all of the
493                  * requested LMBs cannot be removed.
494                  */
495                 lmbs[i].reserved = 1;
496         }
497
498         if (lmbs_removed != lmbs_to_remove) {
499                 pr_err("Memory hot-remove failed, adding LMB's back\n");
500
501                 for (i = 0; i < num_lmbs; i++) {
502                         if (!lmbs[i].reserved)
503                                 continue;
504
505                         rc = dlpar_add_lmb(&lmbs[i]);
506                         if (rc)
507                                 pr_err("Failed to add LMB back, drc index %x\n",
508                                        lmbs[i].drc_index);
509
510                         lmbs[i].reserved = 0;
511                 }
512
513                 rc = -EINVAL;
514         } else {
515                 for (i = 0; i < num_lmbs; i++) {
516                         if (!lmbs[i].reserved)
517                                 continue;
518
519                         pr_info("Memory at %llx was hot-removed\n",
520                                 lmbs[i].base_addr);
521
522                         lmbs[i].reserved = 0;
523                 }
524                 rc = 0;
525         }
526
527         return rc;
528 }
529
530 static int dlpar_memory_remove_by_index(u32 drc_index, struct property *prop)
531 {
532         struct of_drconf_cell *lmbs;
533         u32 num_lmbs, *p;
534         int lmb_found;
535         int i, rc;
536
537         pr_info("Attempting to hot-remove LMB, drc index %x\n", drc_index);
538
539         p = prop->value;
540         num_lmbs = *p++;
541         lmbs = (struct of_drconf_cell *)p;
542
543         lmb_found = 0;
544         for (i = 0; i < num_lmbs; i++) {
545                 if (lmbs[i].drc_index == drc_index) {
546                         lmb_found = 1;
547                         rc = dlpar_remove_lmb(&lmbs[i]);
548                         break;
549                 }
550         }
551
552         if (!lmb_found)
553                 rc = -EINVAL;
554
555         if (rc)
556                 pr_info("Failed to hot-remove memory at %llx\n",
557                         lmbs[i].base_addr);
558         else
559                 pr_info("Memory at %llx was hot-removed\n", lmbs[i].base_addr);
560
561         return rc;
562 }
563
564 #else
565 static inline int pseries_remove_memblock(unsigned long base,
566                                           unsigned int memblock_size)
567 {
568         return -EOPNOTSUPP;
569 }
570 static inline int pseries_remove_mem_node(struct device_node *np)
571 {
572         return 0;
573 }
574 static inline int dlpar_memory_remove(struct pseries_hp_errorlog *hp_elog)
575 {
576         return -EOPNOTSUPP;
577 }
578 static int dlpar_remove_lmb(struct of_drconf_cell *lmb)
579 {
580         return -EOPNOTSUPP;
581 }
582 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove,
583                                         struct property *prop)
584 {
585         return -EOPNOTSUPP;
586 }
587 static int dlpar_memory_remove_by_index(u32 drc_index, struct property *prop)
588 {
589         return -EOPNOTSUPP;
590 }
591
592 #endif /* CONFIG_MEMORY_HOTREMOVE */
593
594 static int dlpar_add_lmb(struct of_drconf_cell *lmb)
595 {
596         unsigned long block_sz;
597         int nid, rc;
598
599         if (lmb->flags & DRCONF_MEM_ASSIGNED)
600                 return -EINVAL;
601
602         rc = dlpar_acquire_drc(lmb->drc_index);
603         if (rc)
604                 return rc;
605
606         rc = dlpar_add_device_tree_lmb(lmb);
607         if (rc) {
608                 pr_err("Couldn't update device tree for drc index %x\n",
609                        lmb->drc_index);
610                 dlpar_release_drc(lmb->drc_index);
611                 return rc;
612         }
613
614         block_sz = memory_block_size_bytes();
615
616         /* Find the node id for this address */
617         nid = memory_add_physaddr_to_nid(lmb->base_addr);
618
619         /* Add the memory */
620         rc = add_memory(nid, lmb->base_addr, block_sz);
621         if (rc) {
622                 dlpar_remove_device_tree_lmb(lmb);
623                 dlpar_release_drc(lmb->drc_index);
624         } else {
625                 lmb->flags |= DRCONF_MEM_ASSIGNED;
626         }
627
628         return rc;
629 }
630
631 static int dlpar_memory_add_by_count(u32 lmbs_to_add, struct property *prop)
632 {
633         struct of_drconf_cell *lmbs;
634         u32 num_lmbs, *p;
635         int lmbs_available = 0;
636         int lmbs_added = 0;
637         int i, rc;
638
639         pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);
640
641         if (lmbs_to_add == 0)
642                 return -EINVAL;
643
644         p = prop->value;
645         num_lmbs = *p++;
646         lmbs = (struct of_drconf_cell *)p;
647
648         /* Validate that there are enough LMBs to satisfy the request */
649         for (i = 0; i < num_lmbs; i++) {
650                 if (!(lmbs[i].flags & DRCONF_MEM_ASSIGNED))
651                         lmbs_available++;
652         }
653
654         if (lmbs_available < lmbs_to_add)
655                 return -EINVAL;
656
657         for (i = 0; i < num_lmbs && lmbs_to_add != lmbs_added; i++) {
658                 rc = dlpar_add_lmb(&lmbs[i]);
659                 if (rc)
660                         continue;
661
662                 lmbs_added++;
663
664                 /* Mark this lmb so we can remove it later if all of the
665                  * requested LMBs cannot be added.
666                  */
667                 lmbs[i].reserved = 1;
668         }
669
670         if (lmbs_added != lmbs_to_add) {
671                 pr_err("Memory hot-add failed, removing any added LMBs\n");
672
673                 for (i = 0; i < num_lmbs; i++) {
674                         if (!lmbs[i].reserved)
675                                 continue;
676
677                         rc = dlpar_remove_lmb(&lmbs[i]);
678                         if (rc)
679                                 pr_err("Failed to remove LMB, drc index %x\n",
680                                        be32_to_cpu(lmbs[i].drc_index));
681                 }
682                 rc = -EINVAL;
683         } else {
684                 for (i = 0; i < num_lmbs; i++) {
685                         if (!lmbs[i].reserved)
686                                 continue;
687
688                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
689                                 lmbs[i].base_addr, lmbs[i].drc_index);
690                         lmbs[i].reserved = 0;
691                 }
692         }
693
694         return rc;
695 }
696
697 static int dlpar_memory_add_by_index(u32 drc_index, struct property *prop)
698 {
699         struct of_drconf_cell *lmbs;
700         u32 num_lmbs, *p;
701         int i, lmb_found;
702         int rc;
703
704         pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);
705
706         p = prop->value;
707         num_lmbs = *p++;
708         lmbs = (struct of_drconf_cell *)p;
709
710         lmb_found = 0;
711         for (i = 0; i < num_lmbs; i++) {
712                 if (lmbs[i].drc_index == drc_index) {
713                         lmb_found = 1;
714                         rc = dlpar_add_lmb(&lmbs[i]);
715                         break;
716                 }
717         }
718
719         if (!lmb_found)
720                 rc = -EINVAL;
721
722         if (rc)
723                 pr_info("Failed to hot-add memory, drc index %x\n", drc_index);
724         else
725                 pr_info("Memory at %llx (drc index %x) was hot-added\n",
726                         lmbs[i].base_addr, drc_index);
727
728         return rc;
729 }
730
731 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
732 {
733         struct device_node *dn;
734         struct property *prop;
735         u32 count, drc_index;
736         int rc;
737
738         count = hp_elog->_drc_u.drc_count;
739         drc_index = hp_elog->_drc_u.drc_index;
740
741         lock_device_hotplug();
742
743         dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
744         if (!dn) {
745                 rc = -EINVAL;
746                 goto dlpar_memory_out;
747         }
748
749         prop = dlpar_clone_drconf_property(dn);
750         if (!prop) {
751                 rc = -EINVAL;
752                 goto dlpar_memory_out;
753         }
754
755         switch (hp_elog->action) {
756         case PSERIES_HP_ELOG_ACTION_ADD:
757                 if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT)
758                         rc = dlpar_memory_add_by_count(count, prop);
759                 else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX)
760                         rc = dlpar_memory_add_by_index(drc_index, prop);
761                 else
762                         rc = -EINVAL;
763                 break;
764         case PSERIES_HP_ELOG_ACTION_REMOVE:
765                 if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT)
766                         rc = dlpar_memory_remove_by_count(count, prop);
767                 else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX)
768                         rc = dlpar_memory_remove_by_index(drc_index, prop);
769                 else
770                         rc = -EINVAL;
771                 break;
772         default:
773                 pr_err("Invalid action (%d) specified\n", hp_elog->action);
774                 rc = -EINVAL;
775                 break;
776         }
777
778         dlpar_free_property(prop);
779
780 dlpar_memory_out:
781         of_node_put(dn);
782         unlock_device_hotplug();
783         return rc;
784 }
785
786 static int pseries_add_mem_node(struct device_node *np)
787 {
788         const char *type;
789         const __be32 *regs;
790         unsigned long base;
791         unsigned int lmb_size;
792         int ret = -EINVAL;
793
794         /*
795          * Check to see if we are actually adding memory
796          */
797         type = of_get_property(np, "device_type", NULL);
798         if (type == NULL || strcmp(type, "memory") != 0)
799                 return 0;
800
801         /*
802          * Find the base and size of the memblock
803          */
804         regs = of_get_property(np, "reg", NULL);
805         if (!regs)
806                 return ret;
807
808         base = be64_to_cpu(*(unsigned long *)regs);
809         lmb_size = be32_to_cpu(regs[3]);
810
811         /*
812          * Update memory region to represent the memory add
813          */
814         ret = memblock_add(base, lmb_size);
815         return (ret < 0) ? -EINVAL : 0;
816 }
817
818 static int pseries_update_drconf_memory(struct of_reconfig_data *pr)
819 {
820         struct of_drconf_cell *new_drmem, *old_drmem;
821         unsigned long memblock_size;
822         u32 entries;
823         __be32 *p;
824         int i, rc = -EINVAL;
825
826         if (rtas_hp_event)
827                 return 0;
828
829         memblock_size = pseries_memory_block_size();
830         if (!memblock_size)
831                 return -EINVAL;
832
833         p = (__be32 *) pr->old_prop->value;
834         if (!p)
835                 return -EINVAL;
836
837         /* The first int of the property is the number of lmb's described
838          * by the property. This is followed by an array of of_drconf_cell
839          * entries. Get the number of entries and skip to the array of
840          * of_drconf_cell's.
841          */
842         entries = be32_to_cpu(*p++);
843         old_drmem = (struct of_drconf_cell *)p;
844
845         p = (__be32 *)pr->prop->value;
846         p++;
847         new_drmem = (struct of_drconf_cell *)p;
848
849         for (i = 0; i < entries; i++) {
850                 if ((be32_to_cpu(old_drmem[i].flags) & DRCONF_MEM_ASSIGNED) &&
851                     (!(be32_to_cpu(new_drmem[i].flags) & DRCONF_MEM_ASSIGNED))) {
852                         rc = pseries_remove_memblock(
853                                 be64_to_cpu(old_drmem[i].base_addr),
854                                                      memblock_size);
855                         break;
856                 } else if ((!(be32_to_cpu(old_drmem[i].flags) &
857                             DRCONF_MEM_ASSIGNED)) &&
858                             (be32_to_cpu(new_drmem[i].flags) &
859                             DRCONF_MEM_ASSIGNED)) {
860                         rc = memblock_add(be64_to_cpu(old_drmem[i].base_addr),
861                                           memblock_size);
862                         rc = (rc < 0) ? -EINVAL : 0;
863                         break;
864                 }
865         }
866         return rc;
867 }
868
869 static int pseries_memory_notifier(struct notifier_block *nb,
870                                    unsigned long action, void *data)
871 {
872         struct of_reconfig_data *rd = data;
873         int err = 0;
874
875         switch (action) {
876         case OF_RECONFIG_ATTACH_NODE:
877                 err = pseries_add_mem_node(rd->dn);
878                 break;
879         case OF_RECONFIG_DETACH_NODE:
880                 err = pseries_remove_mem_node(rd->dn);
881                 break;
882         case OF_RECONFIG_UPDATE_PROPERTY:
883                 if (!strcmp(rd->prop->name, "ibm,dynamic-memory"))
884                         err = pseries_update_drconf_memory(rd);
885                 break;
886         }
887         return notifier_from_errno(err);
888 }
889
890 static struct notifier_block pseries_mem_nb = {
891         .notifier_call = pseries_memory_notifier,
892 };
893
894 static int __init pseries_memory_hotplug_init(void)
895 {
896         if (firmware_has_feature(FW_FEATURE_LPAR))
897                 of_reconfig_notifier_register(&pseries_mem_nb);
898
899         return 0;
900 }
901 machine_device_initcall(pseries, pseries_memory_hotplug_init);