mm/memory_hotplug: make remove_memory() take the device_hotplug_lock
[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 <asm/fadump.h>
26 #include <asm/drmem.h>
27 #include "pseries.h"
28
29 static bool rtas_hp_event;
30
31 unsigned long pseries_memory_block_size(void)
32 {
33         struct device_node *np;
34         unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
35         struct resource r;
36
37         np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
38         if (np) {
39                 const __be64 *size;
40
41                 size = of_get_property(np, "ibm,lmb-size", NULL);
42                 if (size)
43                         memblock_size = be64_to_cpup(size);
44                 of_node_put(np);
45         } else  if (machine_is(pseries)) {
46                 /* This fallback really only applies to pseries */
47                 unsigned int memzero_size = 0;
48
49                 np = of_find_node_by_path("/memory@0");
50                 if (np) {
51                         if (!of_address_to_resource(np, 0, &r))
52                                 memzero_size = resource_size(&r);
53                         of_node_put(np);
54                 }
55
56                 if (memzero_size) {
57                         /* We now know the size of memory@0, use this to find
58                          * the first memoryblock and get its size.
59                          */
60                         char buf[64];
61
62                         sprintf(buf, "/memory@%x", memzero_size);
63                         np = of_find_node_by_path(buf);
64                         if (np) {
65                                 if (!of_address_to_resource(np, 0, &r))
66                                         memblock_size = resource_size(&r);
67                                 of_node_put(np);
68                         }
69                 }
70         }
71         return memblock_size;
72 }
73
74 static void dlpar_free_property(struct property *prop)
75 {
76         kfree(prop->name);
77         kfree(prop->value);
78         kfree(prop);
79 }
80
81 static struct property *dlpar_clone_property(struct property *prop,
82                                              u32 prop_size)
83 {
84         struct property *new_prop;
85
86         new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
87         if (!new_prop)
88                 return NULL;
89
90         new_prop->name = kstrdup(prop->name, GFP_KERNEL);
91         new_prop->value = kzalloc(prop_size, GFP_KERNEL);
92         if (!new_prop->name || !new_prop->value) {
93                 dlpar_free_property(new_prop);
94                 return NULL;
95         }
96
97         memcpy(new_prop->value, prop->value, prop->length);
98         new_prop->length = prop_size;
99
100         of_property_set_flag(new_prop, OF_DYNAMIC);
101         return new_prop;
102 }
103
104 static bool find_aa_index(struct device_node *dr_node,
105                          struct property *ala_prop,
106                          const u32 *lmb_assoc, u32 *aa_index)
107 {
108         u32 *assoc_arrays, new_prop_size;
109         struct property *new_prop;
110         int aa_arrays, aa_array_entries, aa_array_sz;
111         int i, index;
112
113         /*
114          * The ibm,associativity-lookup-arrays property is defined to be
115          * a 32-bit value specifying the number of associativity arrays
116          * followed by a 32-bitvalue specifying the number of entries per
117          * array, followed by the associativity arrays.
118          */
119         assoc_arrays = ala_prop->value;
120
121         aa_arrays = be32_to_cpu(assoc_arrays[0]);
122         aa_array_entries = be32_to_cpu(assoc_arrays[1]);
123         aa_array_sz = aa_array_entries * sizeof(u32);
124
125         for (i = 0; i < aa_arrays; i++) {
126                 index = (i * aa_array_entries) + 2;
127
128                 if (memcmp(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz))
129                         continue;
130
131                 *aa_index = i;
132                 return true;
133         }
134
135         new_prop_size = ala_prop->length + aa_array_sz;
136         new_prop = dlpar_clone_property(ala_prop, new_prop_size);
137         if (!new_prop)
138                 return false;
139
140         assoc_arrays = new_prop->value;
141
142         /* increment the number of entries in the lookup array */
143         assoc_arrays[0] = cpu_to_be32(aa_arrays + 1);
144
145         /* copy the new associativity into the lookup array */
146         index = aa_arrays * aa_array_entries + 2;
147         memcpy(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz);
148
149         of_update_property(dr_node, new_prop);
150
151         /*
152          * The associativity lookup array index for this lmb is
153          * number of entries - 1 since we added its associativity
154          * to the end of the lookup array.
155          */
156         *aa_index = be32_to_cpu(assoc_arrays[0]) - 1;
157         return true;
158 }
159
160 static int update_lmb_associativity_index(struct drmem_lmb *lmb)
161 {
162         struct device_node *parent, *lmb_node, *dr_node;
163         struct property *ala_prop;
164         const u32 *lmb_assoc;
165         u32 aa_index;
166         bool found;
167
168         parent = of_find_node_by_path("/");
169         if (!parent)
170                 return -ENODEV;
171
172         lmb_node = dlpar_configure_connector(cpu_to_be32(lmb->drc_index),
173                                              parent);
174         of_node_put(parent);
175         if (!lmb_node)
176                 return -EINVAL;
177
178         lmb_assoc = of_get_property(lmb_node, "ibm,associativity", NULL);
179         if (!lmb_assoc) {
180                 dlpar_free_cc_nodes(lmb_node);
181                 return -ENODEV;
182         }
183
184         dr_node = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
185         if (!dr_node) {
186                 dlpar_free_cc_nodes(lmb_node);
187                 return -ENODEV;
188         }
189
190         ala_prop = of_find_property(dr_node, "ibm,associativity-lookup-arrays",
191                                     NULL);
192         if (!ala_prop) {
193                 of_node_put(dr_node);
194                 dlpar_free_cc_nodes(lmb_node);
195                 return -ENODEV;
196         }
197
198         found = find_aa_index(dr_node, ala_prop, lmb_assoc, &aa_index);
199
200         dlpar_free_cc_nodes(lmb_node);
201
202         if (!found) {
203                 pr_err("Could not find LMB associativity\n");
204                 return -1;
205         }
206
207         lmb->aa_index = aa_index;
208         return 0;
209 }
210
211 static struct memory_block *lmb_to_memblock(struct drmem_lmb *lmb)
212 {
213         unsigned long section_nr;
214         struct mem_section *mem_sect;
215         struct memory_block *mem_block;
216
217         section_nr = pfn_to_section_nr(PFN_DOWN(lmb->base_addr));
218         mem_sect = __nr_to_section(section_nr);
219
220         mem_block = find_memory_block(mem_sect);
221         return mem_block;
222 }
223
224 static int get_lmb_range(u32 drc_index, int n_lmbs,
225                          struct drmem_lmb **start_lmb,
226                          struct drmem_lmb **end_lmb)
227 {
228         struct drmem_lmb *lmb, *start, *end;
229         struct drmem_lmb *last_lmb;
230
231         start = NULL;
232         for_each_drmem_lmb(lmb) {
233                 if (lmb->drc_index == drc_index) {
234                         start = lmb;
235                         break;
236                 }
237         }
238
239         if (!start)
240                 return -EINVAL;
241
242         end = &start[n_lmbs - 1];
243
244         last_lmb = &drmem_info->lmbs[drmem_info->n_lmbs - 1];
245         if (end > last_lmb)
246                 return -EINVAL;
247
248         *start_lmb = start;
249         *end_lmb = end;
250         return 0;
251 }
252
253 static int dlpar_change_lmb_state(struct drmem_lmb *lmb, bool online)
254 {
255         struct memory_block *mem_block;
256         int rc;
257
258         mem_block = lmb_to_memblock(lmb);
259         if (!mem_block)
260                 return -EINVAL;
261
262         if (online && mem_block->dev.offline)
263                 rc = device_online(&mem_block->dev);
264         else if (!online && !mem_block->dev.offline)
265                 rc = device_offline(&mem_block->dev);
266         else
267                 rc = 0;
268
269         put_device(&mem_block->dev);
270
271         return rc;
272 }
273
274 static int dlpar_online_lmb(struct drmem_lmb *lmb)
275 {
276         return dlpar_change_lmb_state(lmb, true);
277 }
278
279 #ifdef CONFIG_MEMORY_HOTREMOVE
280 static int dlpar_offline_lmb(struct drmem_lmb *lmb)
281 {
282         return dlpar_change_lmb_state(lmb, false);
283 }
284
285 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
286 {
287         unsigned long block_sz, start_pfn;
288         int sections_per_block;
289         int i, nid;
290
291         start_pfn = base >> PAGE_SHIFT;
292
293         lock_device_hotplug();
294
295         if (!pfn_valid(start_pfn))
296                 goto out;
297
298         block_sz = pseries_memory_block_size();
299         sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
300         nid = memory_add_physaddr_to_nid(base);
301
302         for (i = 0; i < sections_per_block; i++) {
303                 __remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
304                 base += MIN_MEMORY_BLOCK_SIZE;
305         }
306
307 out:
308         /* Update memory regions for memory remove */
309         memblock_remove(base, memblock_size);
310         unlock_device_hotplug();
311         return 0;
312 }
313
314 static int pseries_remove_mem_node(struct device_node *np)
315 {
316         const char *type;
317         const __be32 *regs;
318         unsigned long base;
319         unsigned int lmb_size;
320         int ret = -EINVAL;
321
322         /*
323          * Check to see if we are actually removing memory
324          */
325         type = of_get_property(np, "device_type", NULL);
326         if (type == NULL || strcmp(type, "memory") != 0)
327                 return 0;
328
329         /*
330          * Find the base address and size of the memblock
331          */
332         regs = of_get_property(np, "reg", NULL);
333         if (!regs)
334                 return ret;
335
336         base = be64_to_cpu(*(unsigned long *)regs);
337         lmb_size = be32_to_cpu(regs[3]);
338
339         pseries_remove_memblock(base, lmb_size);
340         return 0;
341 }
342
343 static bool lmb_is_removable(struct drmem_lmb *lmb)
344 {
345         int i, scns_per_block;
346         int rc = 1;
347         unsigned long pfn, block_sz;
348         u64 phys_addr;
349
350         if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
351                 return false;
352
353         block_sz = memory_block_size_bytes();
354         scns_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
355         phys_addr = lmb->base_addr;
356
357 #ifdef CONFIG_FA_DUMP
358         /* Don't hot-remove memory that falls in fadump boot memory area */
359         if (is_fadump_boot_memory_area(phys_addr, block_sz))
360                 return false;
361 #endif
362
363         for (i = 0; i < scns_per_block; i++) {
364                 pfn = PFN_DOWN(phys_addr);
365                 if (!pfn_present(pfn))
366                         continue;
367
368                 rc &= is_mem_section_removable(pfn, PAGES_PER_SECTION);
369                 phys_addr += MIN_MEMORY_BLOCK_SIZE;
370         }
371
372         return rc ? true : false;
373 }
374
375 static int dlpar_add_lmb(struct drmem_lmb *);
376
377 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
378 {
379         unsigned long block_sz;
380         int nid, rc;
381
382         if (!lmb_is_removable(lmb))
383                 return -EINVAL;
384
385         rc = dlpar_offline_lmb(lmb);
386         if (rc)
387                 return rc;
388
389         block_sz = pseries_memory_block_size();
390         nid = memory_add_physaddr_to_nid(lmb->base_addr);
391
392         __remove_memory(nid, lmb->base_addr, block_sz);
393
394         /* Update memory regions for memory remove */
395         memblock_remove(lmb->base_addr, block_sz);
396
397         invalidate_lmb_associativity_index(lmb);
398         lmb->flags &= ~DRCONF_MEM_ASSIGNED;
399
400         return 0;
401 }
402
403 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
404 {
405         struct drmem_lmb *lmb;
406         int lmbs_removed = 0;
407         int lmbs_available = 0;
408         int rc;
409
410         pr_info("Attempting to hot-remove %d LMB(s)\n", lmbs_to_remove);
411
412         if (lmbs_to_remove == 0)
413                 return -EINVAL;
414
415         /* Validate that there are enough LMBs to satisfy the request */
416         for_each_drmem_lmb(lmb) {
417                 if (lmb_is_removable(lmb))
418                         lmbs_available++;
419
420                 if (lmbs_available == lmbs_to_remove)
421                         break;
422         }
423
424         if (lmbs_available < lmbs_to_remove) {
425                 pr_info("Not enough LMBs available (%d of %d) to satisfy request\n",
426                         lmbs_available, lmbs_to_remove);
427                 return -EINVAL;
428         }
429
430         for_each_drmem_lmb(lmb) {
431                 rc = dlpar_remove_lmb(lmb);
432                 if (rc)
433                         continue;
434
435                 /* Mark this lmb so we can add it later if all of the
436                  * requested LMBs cannot be removed.
437                  */
438                 drmem_mark_lmb_reserved(lmb);
439
440                 lmbs_removed++;
441                 if (lmbs_removed == lmbs_to_remove)
442                         break;
443         }
444
445         if (lmbs_removed != lmbs_to_remove) {
446                 pr_err("Memory hot-remove failed, adding LMB's back\n");
447
448                 for_each_drmem_lmb(lmb) {
449                         if (!drmem_lmb_reserved(lmb))
450                                 continue;
451
452                         rc = dlpar_add_lmb(lmb);
453                         if (rc)
454                                 pr_err("Failed to add LMB back, drc index %x\n",
455                                        lmb->drc_index);
456
457                         drmem_remove_lmb_reservation(lmb);
458                 }
459
460                 rc = -EINVAL;
461         } else {
462                 for_each_drmem_lmb(lmb) {
463                         if (!drmem_lmb_reserved(lmb))
464                                 continue;
465
466                         dlpar_release_drc(lmb->drc_index);
467                         pr_info("Memory at %llx was hot-removed\n",
468                                 lmb->base_addr);
469
470                         drmem_remove_lmb_reservation(lmb);
471                 }
472                 rc = 0;
473         }
474
475         return rc;
476 }
477
478 static int dlpar_memory_remove_by_index(u32 drc_index)
479 {
480         struct drmem_lmb *lmb;
481         int lmb_found;
482         int rc;
483
484         pr_info("Attempting to hot-remove LMB, drc index %x\n", drc_index);
485
486         lmb_found = 0;
487         for_each_drmem_lmb(lmb) {
488                 if (lmb->drc_index == drc_index) {
489                         lmb_found = 1;
490                         rc = dlpar_remove_lmb(lmb);
491                         if (!rc)
492                                 dlpar_release_drc(lmb->drc_index);
493
494                         break;
495                 }
496         }
497
498         if (!lmb_found)
499                 rc = -EINVAL;
500
501         if (rc)
502                 pr_info("Failed to hot-remove memory at %llx\n",
503                         lmb->base_addr);
504         else
505                 pr_info("Memory at %llx was hot-removed\n", lmb->base_addr);
506
507         return rc;
508 }
509
510 static int dlpar_memory_readd_by_index(u32 drc_index)
511 {
512         struct drmem_lmb *lmb;
513         int lmb_found;
514         int rc;
515
516         pr_info("Attempting to update LMB, drc index %x\n", drc_index);
517
518         lmb_found = 0;
519         for_each_drmem_lmb(lmb) {
520                 if (lmb->drc_index == drc_index) {
521                         lmb_found = 1;
522                         rc = dlpar_remove_lmb(lmb);
523                         if (!rc) {
524                                 rc = dlpar_add_lmb(lmb);
525                                 if (rc)
526                                         dlpar_release_drc(lmb->drc_index);
527                         }
528                         break;
529                 }
530         }
531
532         if (!lmb_found)
533                 rc = -EINVAL;
534
535         if (rc)
536                 pr_info("Failed to update memory at %llx\n",
537                         lmb->base_addr);
538         else
539                 pr_info("Memory at %llx was updated\n", lmb->base_addr);
540
541         return rc;
542 }
543
544 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
545 {
546         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
547         int lmbs_available = 0;
548         int rc;
549
550         pr_info("Attempting to hot-remove %u LMB(s) at %x\n",
551                 lmbs_to_remove, drc_index);
552
553         if (lmbs_to_remove == 0)
554                 return -EINVAL;
555
556         rc = get_lmb_range(drc_index, lmbs_to_remove, &start_lmb, &end_lmb);
557         if (rc)
558                 return -EINVAL;
559
560         /* Validate that there are enough LMBs to satisfy the request */
561         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
562                 if (lmb->flags & DRCONF_MEM_RESERVED)
563                         break;
564
565                 lmbs_available++;
566         }
567
568         if (lmbs_available < lmbs_to_remove)
569                 return -EINVAL;
570
571         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
572                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
573                         continue;
574
575                 rc = dlpar_remove_lmb(lmb);
576                 if (rc)
577                         break;
578
579                 drmem_mark_lmb_reserved(lmb);
580         }
581
582         if (rc) {
583                 pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
584
585
586                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
587                         if (!drmem_lmb_reserved(lmb))
588                                 continue;
589
590                         rc = dlpar_add_lmb(lmb);
591                         if (rc)
592                                 pr_err("Failed to add LMB, drc index %x\n",
593                                        lmb->drc_index);
594
595                         drmem_remove_lmb_reservation(lmb);
596                 }
597                 rc = -EINVAL;
598         } else {
599                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
600                         if (!drmem_lmb_reserved(lmb))
601                                 continue;
602
603                         dlpar_release_drc(lmb->drc_index);
604                         pr_info("Memory at %llx (drc index %x) was hot-removed\n",
605                                 lmb->base_addr, lmb->drc_index);
606
607                         drmem_remove_lmb_reservation(lmb);
608                 }
609         }
610
611         return rc;
612 }
613
614 #else
615 static inline int pseries_remove_memblock(unsigned long base,
616                                           unsigned int memblock_size)
617 {
618         return -EOPNOTSUPP;
619 }
620 static inline int pseries_remove_mem_node(struct device_node *np)
621 {
622         return 0;
623 }
624 static inline int dlpar_memory_remove(struct pseries_hp_errorlog *hp_elog)
625 {
626         return -EOPNOTSUPP;
627 }
628 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
629 {
630         return -EOPNOTSUPP;
631 }
632 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
633 {
634         return -EOPNOTSUPP;
635 }
636 static int dlpar_memory_remove_by_index(u32 drc_index)
637 {
638         return -EOPNOTSUPP;
639 }
640 static int dlpar_memory_readd_by_index(u32 drc_index)
641 {
642         return -EOPNOTSUPP;
643 }
644
645 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
646 {
647         return -EOPNOTSUPP;
648 }
649 #endif /* CONFIG_MEMORY_HOTREMOVE */
650
651 static int dlpar_add_lmb(struct drmem_lmb *lmb)
652 {
653         unsigned long block_sz;
654         int nid, rc;
655
656         if (lmb->flags & DRCONF_MEM_ASSIGNED)
657                 return -EINVAL;
658
659         rc = update_lmb_associativity_index(lmb);
660         if (rc) {
661                 dlpar_release_drc(lmb->drc_index);
662                 return rc;
663         }
664
665         block_sz = memory_block_size_bytes();
666
667         /* Find the node id for this address */
668         nid = memory_add_physaddr_to_nid(lmb->base_addr);
669
670         /* Add the memory */
671         rc = add_memory(nid, lmb->base_addr, block_sz);
672         if (rc) {
673                 invalidate_lmb_associativity_index(lmb);
674                 return rc;
675         }
676
677         rc = dlpar_online_lmb(lmb);
678         if (rc) {
679                 __remove_memory(nid, lmb->base_addr, block_sz);
680                 invalidate_lmb_associativity_index(lmb);
681         } else {
682                 lmb->flags |= DRCONF_MEM_ASSIGNED;
683         }
684
685         return rc;
686 }
687
688 static int dlpar_memory_add_by_count(u32 lmbs_to_add)
689 {
690         struct drmem_lmb *lmb;
691         int lmbs_available = 0;
692         int lmbs_added = 0;
693         int rc;
694
695         pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);
696
697         if (lmbs_to_add == 0)
698                 return -EINVAL;
699
700         /* Validate that there are enough LMBs to satisfy the request */
701         for_each_drmem_lmb(lmb) {
702                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
703                         lmbs_available++;
704
705                 if (lmbs_available == lmbs_to_add)
706                         break;
707         }
708
709         if (lmbs_available < lmbs_to_add)
710                 return -EINVAL;
711
712         for_each_drmem_lmb(lmb) {
713                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
714                         continue;
715
716                 rc = dlpar_acquire_drc(lmb->drc_index);
717                 if (rc)
718                         continue;
719
720                 rc = dlpar_add_lmb(lmb);
721                 if (rc) {
722                         dlpar_release_drc(lmb->drc_index);
723                         continue;
724                 }
725
726                 /* Mark this lmb so we can remove it later if all of the
727                  * requested LMBs cannot be added.
728                  */
729                 drmem_mark_lmb_reserved(lmb);
730
731                 lmbs_added++;
732                 if (lmbs_added == lmbs_to_add)
733                         break;
734         }
735
736         if (lmbs_added != lmbs_to_add) {
737                 pr_err("Memory hot-add failed, removing any added LMBs\n");
738
739                 for_each_drmem_lmb(lmb) {
740                         if (!drmem_lmb_reserved(lmb))
741                                 continue;
742
743                         rc = dlpar_remove_lmb(lmb);
744                         if (rc)
745                                 pr_err("Failed to remove LMB, drc index %x\n",
746                                        lmb->drc_index);
747                         else
748                                 dlpar_release_drc(lmb->drc_index);
749
750                         drmem_remove_lmb_reservation(lmb);
751                 }
752                 rc = -EINVAL;
753         } else {
754                 for_each_drmem_lmb(lmb) {
755                         if (!drmem_lmb_reserved(lmb))
756                                 continue;
757
758                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
759                                 lmb->base_addr, lmb->drc_index);
760                         drmem_remove_lmb_reservation(lmb);
761                 }
762                 rc = 0;
763         }
764
765         return rc;
766 }
767
768 static int dlpar_memory_add_by_index(u32 drc_index)
769 {
770         struct drmem_lmb *lmb;
771         int rc, lmb_found;
772
773         pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);
774
775         lmb_found = 0;
776         for_each_drmem_lmb(lmb) {
777                 if (lmb->drc_index == drc_index) {
778                         lmb_found = 1;
779                         rc = dlpar_acquire_drc(lmb->drc_index);
780                         if (!rc) {
781                                 rc = dlpar_add_lmb(lmb);
782                                 if (rc)
783                                         dlpar_release_drc(lmb->drc_index);
784                         }
785
786                         break;
787                 }
788         }
789
790         if (!lmb_found)
791                 rc = -EINVAL;
792
793         if (rc)
794                 pr_info("Failed to hot-add memory, drc index %x\n", drc_index);
795         else
796                 pr_info("Memory at %llx (drc index %x) was hot-added\n",
797                         lmb->base_addr, drc_index);
798
799         return rc;
800 }
801
802 static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
803 {
804         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
805         int lmbs_available = 0;
806         int rc;
807
808         pr_info("Attempting to hot-add %u LMB(s) at index %x\n",
809                 lmbs_to_add, drc_index);
810
811         if (lmbs_to_add == 0)
812                 return -EINVAL;
813
814         rc = get_lmb_range(drc_index, lmbs_to_add, &start_lmb, &end_lmb);
815         if (rc)
816                 return -EINVAL;
817
818         /* Validate that the LMBs in this range are not reserved */
819         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
820                 if (lmb->flags & DRCONF_MEM_RESERVED)
821                         break;
822
823                 lmbs_available++;
824         }
825
826         if (lmbs_available < lmbs_to_add)
827                 return -EINVAL;
828
829         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
830                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
831                         continue;
832
833                 rc = dlpar_acquire_drc(lmb->drc_index);
834                 if (rc)
835                         break;
836
837                 rc = dlpar_add_lmb(lmb);
838                 if (rc) {
839                         dlpar_release_drc(lmb->drc_index);
840                         break;
841                 }
842
843                 drmem_mark_lmb_reserved(lmb);
844         }
845
846         if (rc) {
847                 pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
848
849                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
850                         if (!drmem_lmb_reserved(lmb))
851                                 continue;
852
853                         rc = dlpar_remove_lmb(lmb);
854                         if (rc)
855                                 pr_err("Failed to remove LMB, drc index %x\n",
856                                        lmb->drc_index);
857                         else
858                                 dlpar_release_drc(lmb->drc_index);
859
860                         drmem_remove_lmb_reservation(lmb);
861                 }
862                 rc = -EINVAL;
863         } else {
864                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
865                         if (!drmem_lmb_reserved(lmb))
866                                 continue;
867
868                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
869                                 lmb->base_addr, lmb->drc_index);
870                         drmem_remove_lmb_reservation(lmb);
871                 }
872         }
873
874         return rc;
875 }
876
877 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
878 {
879         u32 count, drc_index;
880         int rc;
881
882         lock_device_hotplug();
883
884         switch (hp_elog->action) {
885         case PSERIES_HP_ELOG_ACTION_ADD:
886                 if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) {
887                         count = hp_elog->_drc_u.drc_count;
888                         rc = dlpar_memory_add_by_count(count);
889                 } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) {
890                         drc_index = hp_elog->_drc_u.drc_index;
891                         rc = dlpar_memory_add_by_index(drc_index);
892                 } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_IC) {
893                         count = hp_elog->_drc_u.ic.count;
894                         drc_index = hp_elog->_drc_u.ic.index;
895                         rc = dlpar_memory_add_by_ic(count, drc_index);
896                 } else {
897                         rc = -EINVAL;
898                 }
899
900                 break;
901         case PSERIES_HP_ELOG_ACTION_REMOVE:
902                 if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) {
903                         count = hp_elog->_drc_u.drc_count;
904                         rc = dlpar_memory_remove_by_count(count);
905                 } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) {
906                         drc_index = hp_elog->_drc_u.drc_index;
907                         rc = dlpar_memory_remove_by_index(drc_index);
908                 } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_IC) {
909                         count = hp_elog->_drc_u.ic.count;
910                         drc_index = hp_elog->_drc_u.ic.index;
911                         rc = dlpar_memory_remove_by_ic(count, drc_index);
912                 } else {
913                         rc = -EINVAL;
914                 }
915
916                 break;
917         case PSERIES_HP_ELOG_ACTION_READD:
918                 drc_index = hp_elog->_drc_u.drc_index;
919                 rc = dlpar_memory_readd_by_index(drc_index);
920                 break;
921         default:
922                 pr_err("Invalid action (%d) specified\n", hp_elog->action);
923                 rc = -EINVAL;
924                 break;
925         }
926
927         if (!rc) {
928                 rtas_hp_event = true;
929                 rc = drmem_update_dt();
930                 rtas_hp_event = false;
931         }
932
933         unlock_device_hotplug();
934         return rc;
935 }
936
937 static int pseries_add_mem_node(struct device_node *np)
938 {
939         const char *type;
940         const __be32 *regs;
941         unsigned long base;
942         unsigned int lmb_size;
943         int ret = -EINVAL;
944
945         /*
946          * Check to see if we are actually adding memory
947          */
948         type = of_get_property(np, "device_type", NULL);
949         if (type == NULL || strcmp(type, "memory") != 0)
950                 return 0;
951
952         /*
953          * Find the base and size of the memblock
954          */
955         regs = of_get_property(np, "reg", NULL);
956         if (!regs)
957                 return ret;
958
959         base = be64_to_cpu(*(unsigned long *)regs);
960         lmb_size = be32_to_cpu(regs[3]);
961
962         /*
963          * Update memory region to represent the memory add
964          */
965         ret = memblock_add(base, lmb_size);
966         return (ret < 0) ? -EINVAL : 0;
967 }
968
969 static int pseries_update_drconf_memory(struct of_reconfig_data *pr)
970 {
971         struct of_drconf_cell_v1 *new_drmem, *old_drmem;
972         unsigned long memblock_size;
973         u32 entries;
974         __be32 *p;
975         int i, rc = -EINVAL;
976
977         if (rtas_hp_event)
978                 return 0;
979
980         memblock_size = pseries_memory_block_size();
981         if (!memblock_size)
982                 return -EINVAL;
983
984         p = (__be32 *) pr->old_prop->value;
985         if (!p)
986                 return -EINVAL;
987
988         /* The first int of the property is the number of lmb's described
989          * by the property. This is followed by an array of of_drconf_cell
990          * entries. Get the number of entries and skip to the array of
991          * of_drconf_cell's.
992          */
993         entries = be32_to_cpu(*p++);
994         old_drmem = (struct of_drconf_cell_v1 *)p;
995
996         p = (__be32 *)pr->prop->value;
997         p++;
998         new_drmem = (struct of_drconf_cell_v1 *)p;
999
1000         for (i = 0; i < entries; i++) {
1001                 if ((be32_to_cpu(old_drmem[i].flags) & DRCONF_MEM_ASSIGNED) &&
1002                     (!(be32_to_cpu(new_drmem[i].flags) & DRCONF_MEM_ASSIGNED))) {
1003                         rc = pseries_remove_memblock(
1004                                 be64_to_cpu(old_drmem[i].base_addr),
1005                                                      memblock_size);
1006                         break;
1007                 } else if ((!(be32_to_cpu(old_drmem[i].flags) &
1008                             DRCONF_MEM_ASSIGNED)) &&
1009                             (be32_to_cpu(new_drmem[i].flags) &
1010                             DRCONF_MEM_ASSIGNED)) {
1011                         rc = memblock_add(be64_to_cpu(old_drmem[i].base_addr),
1012                                           memblock_size);
1013                         rc = (rc < 0) ? -EINVAL : 0;
1014                         break;
1015                 }
1016         }
1017         return rc;
1018 }
1019
1020 static int pseries_memory_notifier(struct notifier_block *nb,
1021                                    unsigned long action, void *data)
1022 {
1023         struct of_reconfig_data *rd = data;
1024         int err = 0;
1025
1026         switch (action) {
1027         case OF_RECONFIG_ATTACH_NODE:
1028                 err = pseries_add_mem_node(rd->dn);
1029                 break;
1030         case OF_RECONFIG_DETACH_NODE:
1031                 err = pseries_remove_mem_node(rd->dn);
1032                 break;
1033         case OF_RECONFIG_UPDATE_PROPERTY:
1034                 if (!strcmp(rd->prop->name, "ibm,dynamic-memory"))
1035                         err = pseries_update_drconf_memory(rd);
1036                 break;
1037         }
1038         return notifier_from_errno(err);
1039 }
1040
1041 static struct notifier_block pseries_mem_nb = {
1042         .notifier_call = pseries_memory_notifier,
1043 };
1044
1045 static int __init pseries_memory_hotplug_init(void)
1046 {
1047         if (firmware_has_feature(FW_FEATURE_LPAR))
1048                 of_reconfig_notifier_register(&pseries_mem_nb);
1049
1050         return 0;
1051 }
1052 machine_device_initcall(pseries, pseries_memory_hotplug_init);