Commit | Line | Data |
---|---|---|
57b53926 BP |
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 | #include <linux/of.h> | |
13 | #include <asm/firmware.h> | |
14 | #include <asm/machdep.h> | |
15 | #include <asm/pSeries_reconfig.h> | |
16 | ||
17 | static int pseries_remove_memory(struct device_node *np) | |
18 | { | |
19 | const char *type; | |
20 | const unsigned int *my_index; | |
21 | const unsigned int *regs; | |
22 | u64 start_pfn, start; | |
23 | struct zone *zone; | |
24 | int ret = -EINVAL; | |
25 | ||
26 | /* | |
27 | * Check to see if we are actually removing memory | |
28 | */ | |
29 | type = of_get_property(np, "device_type", NULL); | |
30 | if (type == NULL || strcmp(type, "memory") != 0) | |
31 | return 0; | |
32 | ||
33 | /* | |
34 | * Find the memory index and size of the removing section | |
35 | */ | |
36 | my_index = of_get_property(np, "ibm,my-drc-index", NULL); | |
37 | if (!my_index) | |
38 | return ret; | |
39 | ||
40 | regs = of_get_property(np, "reg", NULL); | |
41 | if (!regs) | |
42 | return ret; | |
43 | ||
44 | start_pfn = section_nr_to_pfn(*my_index & 0xffff); | |
45 | zone = page_zone(pfn_to_page(start_pfn)); | |
46 | ||
47 | /* | |
48 | * Remove section mappings and sysfs entries for the | |
49 | * section of the memory we are removing. | |
50 | * | |
51 | * NOTE: Ideally, this should be done in generic code like | |
52 | * remove_memory(). But remove_memory() gets called by writing | |
53 | * to sysfs "state" file and we can't remove sysfs entries | |
54 | * while writing to it. So we have to defer it to here. | |
55 | */ | |
56 | ret = __remove_pages(zone, start_pfn, regs[3] >> PAGE_SHIFT); | |
57 | if (ret) | |
58 | return ret; | |
59 | ||
60 | /* | |
61 | * Remove htab bolted mappings for this section of memory | |
62 | */ | |
63 | start = (unsigned long)__va(start_pfn << PAGE_SHIFT); | |
64 | ret = remove_section_mapping(start, start + regs[3]); | |
65 | return ret; | |
66 | } | |
67 | ||
68 | static int pseries_memory_notifier(struct notifier_block *nb, | |
69 | unsigned long action, void *node) | |
70 | { | |
71 | int err = NOTIFY_OK; | |
72 | ||
73 | switch (action) { | |
74 | case PSERIES_RECONFIG_ADD: | |
75 | break; | |
76 | case PSERIES_RECONFIG_REMOVE: | |
77 | if (pseries_remove_memory(node)) | |
78 | err = NOTIFY_BAD; | |
79 | break; | |
80 | default: | |
81 | err = NOTIFY_DONE; | |
82 | break; | |
83 | } | |
84 | return err; | |
85 | } | |
86 | ||
87 | static struct notifier_block pseries_mem_nb = { | |
88 | .notifier_call = pseries_memory_notifier, | |
89 | }; | |
90 | ||
91 | static int __init pseries_memory_hotplug_init(void) | |
92 | { | |
93 | if (firmware_has_feature(FW_FEATURE_LPAR)) | |
94 | pSeries_reconfig_notifier_register(&pseries_mem_nb); | |
95 | ||
96 | return 0; | |
97 | } | |
98 | machine_device_initcall(pseries, pseries_memory_hotplug_init); |