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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * OS info memory interface
4 *
5 * Copyright IBM Corp. 2012
6 * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
7 */
8
9#define KMSG_COMPONENT "os_info"
10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12#include <linux/crash_dump.h>
13#include <linux/kernel.h>
14#include <linux/slab.h>
15#include <asm/checksum.h>
16#include <asm/abs_lowcore.h>
17#include <asm/os_info.h>
18#include <asm/physmem_info.h>
19#include <asm/maccess.h>
20#include <asm/asm-offsets.h>
21#include <asm/ipl.h>
22
23/*
24 * OS info structure has to be page aligned
25 */
26static struct os_info os_info __page_aligned_data;
27
28/*
29 * Compute checksum over OS info structure
30 */
31u32 os_info_csum(struct os_info *os_info)
32{
33 int size = sizeof(*os_info) - offsetof(struct os_info, version_major);
34 return (__force u32)cksm(&os_info->version_major, size, 0);
35}
36
37/*
38 * Add crashkernel info to OS info and update checksum
39 */
40void os_info_crashkernel_add(unsigned long base, unsigned long size)
41{
42 os_info.crashkernel_addr = (u64)(unsigned long)base;
43 os_info.crashkernel_size = (u64)(unsigned long)size;
44 os_info.csum = os_info_csum(&os_info);
45}
46
47/*
48 * Add OS info data entry and update checksum
49 */
50void os_info_entry_add_data(int nr, void *ptr, u64 size)
51{
52 os_info.entry[nr].addr = __pa(ptr);
53 os_info.entry[nr].size = size;
54 os_info.entry[nr].csum = (__force u32)cksm(ptr, size, 0);
55 os_info.csum = os_info_csum(&os_info);
56}
57
58/*
59 * Add OS info value entry and update checksum
60 */
61void os_info_entry_add_val(int nr, u64 value)
62{
63 os_info.entry[nr].val = value;
64 os_info.entry[nr].size = 0;
65 os_info.entry[nr].csum = 0;
66 os_info.csum = os_info_csum(&os_info);
67}
68
69/*
70 * Initialize OS info structure and set lowcore pointer
71 */
72void __init os_info_init(void)
73{
74 struct lowcore *abs_lc;
75
76 BUILD_BUG_ON(sizeof(struct os_info) != PAGE_SIZE);
77 os_info.version_major = OS_INFO_VERSION_MAJOR;
78 os_info.version_minor = OS_INFO_VERSION_MINOR;
79 os_info.magic = OS_INFO_MAGIC;
80 os_info_entry_add_val(OS_INFO_IDENTITY_BASE, __identity_base);
81 os_info_entry_add_val(OS_INFO_KASLR_OFFSET, kaslr_offset());
82 os_info_entry_add_val(OS_INFO_KASLR_OFF_PHYS, __kaslr_offset_phys);
83 os_info_entry_add_val(OS_INFO_VMEMMAP, (unsigned long)vmemmap);
84 os_info_entry_add_val(OS_INFO_AMODE31_START, AMODE31_START);
85 os_info_entry_add_val(OS_INFO_AMODE31_END, AMODE31_END);
86 os_info_entry_add_val(OS_INFO_IMAGE_START, (unsigned long)_stext);
87 os_info_entry_add_val(OS_INFO_IMAGE_END, (unsigned long)_end);
88 os_info_entry_add_val(OS_INFO_IMAGE_PHYS, __pa_symbol(_stext));
89 os_info.csum = os_info_csum(&os_info);
90 abs_lc = get_abs_lowcore();
91 abs_lc->os_info = __pa(&os_info);
92 put_abs_lowcore(abs_lc);
93}
94
95#ifdef CONFIG_CRASH_DUMP
96
97static struct os_info *os_info_old;
98
99/*
100 * Allocate and copy OS info entry from oldmem
101 */
102static void os_info_old_alloc(int nr, int align)
103{
104 unsigned long addr, size = 0;
105 char *buf, *buf_align, *msg;
106 u32 csum;
107
108 addr = os_info_old->entry[nr].addr;
109 if (!addr) {
110 msg = "not available";
111 goto fail;
112 }
113 size = os_info_old->entry[nr].size;
114 buf = kmalloc(size + align - 1, GFP_KERNEL);
115 if (!buf) {
116 msg = "alloc failed";
117 goto fail;
118 }
119 buf_align = PTR_ALIGN(buf, align);
120 if (copy_oldmem_kernel(buf_align, addr, size)) {
121 msg = "copy failed";
122 goto fail_free;
123 }
124 csum = (__force u32)cksm(buf_align, size, 0);
125 if (csum != os_info_old->entry[nr].csum) {
126 msg = "checksum failed";
127 goto fail_free;
128 }
129 os_info_old->entry[nr].addr = (u64)(unsigned long)buf_align;
130 msg = "copied";
131 goto out;
132fail_free:
133 kfree(buf);
134fail:
135 os_info_old->entry[nr].addr = 0;
136out:
137 pr_info("entry %i: %s (addr=0x%lx size=%lu)\n",
138 nr, msg, addr, size);
139}
140
141/*
142 * Initialize os info and os info entries from oldmem
143 */
144static void os_info_old_init(void)
145{
146 static int os_info_init;
147 unsigned long addr;
148
149 if (os_info_init)
150 return;
151 if (!oldmem_data.start && !is_ipl_type_dump())
152 goto fail;
153 if (copy_oldmem_kernel(&addr, __LC_OS_INFO, sizeof(addr)))
154 goto fail;
155 if (addr == 0 || addr % PAGE_SIZE)
156 goto fail;
157 os_info_old = kzalloc(sizeof(*os_info_old), GFP_KERNEL);
158 if (!os_info_old)
159 goto fail;
160 if (copy_oldmem_kernel(os_info_old, addr, sizeof(*os_info_old)))
161 goto fail_free;
162 if (os_info_old->magic != OS_INFO_MAGIC)
163 goto fail_free;
164 if (os_info_old->csum != os_info_csum(os_info_old))
165 goto fail_free;
166 if (os_info_old->version_major > OS_INFO_VERSION_MAJOR)
167 goto fail_free;
168 os_info_old_alloc(OS_INFO_VMCOREINFO, 1);
169 os_info_old_alloc(OS_INFO_REIPL_BLOCK, 1);
170 pr_info("crashkernel: addr=0x%lx size=%lu\n",
171 (unsigned long) os_info_old->crashkernel_addr,
172 (unsigned long) os_info_old->crashkernel_size);
173 os_info_init = 1;
174 return;
175fail_free:
176 kfree(os_info_old);
177fail:
178 os_info_init = 1;
179 os_info_old = NULL;
180}
181
182/*
183 * Return pointer to os info entry and its size
184 */
185void *os_info_old_entry(int nr, unsigned long *size)
186{
187 os_info_old_init();
188
189 if (!os_info_old)
190 return NULL;
191 if (!os_info_old->entry[nr].addr)
192 return NULL;
193 *size = (unsigned long) os_info_old->entry[nr].size;
194 return (void *)(unsigned long)os_info_old->entry[nr].addr;
195}
196#endif
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * OS info memory interface
4 *
5 * Copyright IBM Corp. 2012
6 * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
7 */
8
9#define KMSG_COMPONENT "os_info"
10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12#include <linux/crash_dump.h>
13#include <linux/kernel.h>
14#include <linux/slab.h>
15#include <asm/checksum.h>
16#include <asm/abs_lowcore.h>
17#include <asm/os_info.h>
18#include <asm/maccess.h>
19#include <asm/asm-offsets.h>
20
21/*
22 * OS info structure has to be page aligned
23 */
24static struct os_info os_info __page_aligned_data;
25
26/*
27 * Compute checksum over OS info structure
28 */
29u32 os_info_csum(struct os_info *os_info)
30{
31 int size = sizeof(*os_info) - offsetof(struct os_info, version_major);
32 return (__force u32)csum_partial(&os_info->version_major, size, 0);
33}
34
35/*
36 * Add crashkernel info to OS info and update checksum
37 */
38void os_info_crashkernel_add(unsigned long base, unsigned long size)
39{
40 os_info.crashkernel_addr = (u64)(unsigned long)base;
41 os_info.crashkernel_size = (u64)(unsigned long)size;
42 os_info.csum = os_info_csum(&os_info);
43}
44
45/*
46 * Add OS info entry and update checksum
47 */
48void os_info_entry_add(int nr, void *ptr, u64 size)
49{
50 os_info.entry[nr].addr = __pa(ptr);
51 os_info.entry[nr].size = size;
52 os_info.entry[nr].csum = (__force u32)csum_partial(ptr, size, 0);
53 os_info.csum = os_info_csum(&os_info);
54}
55
56/*
57 * Initialize OS info structure and set lowcore pointer
58 */
59void __init os_info_init(void)
60{
61 struct lowcore *abs_lc;
62 unsigned long flags;
63
64 os_info.version_major = OS_INFO_VERSION_MAJOR;
65 os_info.version_minor = OS_INFO_VERSION_MINOR;
66 os_info.magic = OS_INFO_MAGIC;
67 os_info.csum = os_info_csum(&os_info);
68 abs_lc = get_abs_lowcore(&flags);
69 abs_lc->os_info = __pa(&os_info);
70 put_abs_lowcore(abs_lc, flags);
71}
72
73#ifdef CONFIG_CRASH_DUMP
74
75static struct os_info *os_info_old;
76
77/*
78 * Allocate and copy OS info entry from oldmem
79 */
80static void os_info_old_alloc(int nr, int align)
81{
82 unsigned long addr, size = 0;
83 char *buf, *buf_align, *msg;
84 u32 csum;
85
86 addr = os_info_old->entry[nr].addr;
87 if (!addr) {
88 msg = "not available";
89 goto fail;
90 }
91 size = os_info_old->entry[nr].size;
92 buf = kmalloc(size + align - 1, GFP_KERNEL);
93 if (!buf) {
94 msg = "alloc failed";
95 goto fail;
96 }
97 buf_align = PTR_ALIGN(buf, align);
98 if (copy_oldmem_kernel(buf_align, addr, size)) {
99 msg = "copy failed";
100 goto fail_free;
101 }
102 csum = (__force u32)csum_partial(buf_align, size, 0);
103 if (csum != os_info_old->entry[nr].csum) {
104 msg = "checksum failed";
105 goto fail_free;
106 }
107 os_info_old->entry[nr].addr = (u64)(unsigned long)buf_align;
108 msg = "copied";
109 goto out;
110fail_free:
111 kfree(buf);
112fail:
113 os_info_old->entry[nr].addr = 0;
114out:
115 pr_info("entry %i: %s (addr=0x%lx size=%lu)\n",
116 nr, msg, addr, size);
117}
118
119/*
120 * Initialize os info and os info entries from oldmem
121 */
122static void os_info_old_init(void)
123{
124 static int os_info_init;
125 unsigned long addr;
126
127 if (os_info_init)
128 return;
129 if (!oldmem_data.start)
130 goto fail;
131 if (copy_oldmem_kernel(&addr, __LC_OS_INFO, sizeof(addr)))
132 goto fail;
133 if (addr == 0 || addr % PAGE_SIZE)
134 goto fail;
135 os_info_old = kzalloc(sizeof(*os_info_old), GFP_KERNEL);
136 if (!os_info_old)
137 goto fail;
138 if (copy_oldmem_kernel(os_info_old, addr, sizeof(*os_info_old)))
139 goto fail_free;
140 if (os_info_old->magic != OS_INFO_MAGIC)
141 goto fail_free;
142 if (os_info_old->csum != os_info_csum(os_info_old))
143 goto fail_free;
144 if (os_info_old->version_major > OS_INFO_VERSION_MAJOR)
145 goto fail_free;
146 os_info_old_alloc(OS_INFO_VMCOREINFO, 1);
147 os_info_old_alloc(OS_INFO_REIPL_BLOCK, 1);
148 pr_info("crashkernel: addr=0x%lx size=%lu\n",
149 (unsigned long) os_info_old->crashkernel_addr,
150 (unsigned long) os_info_old->crashkernel_size);
151 os_info_init = 1;
152 return;
153fail_free:
154 kfree(os_info_old);
155fail:
156 os_info_init = 1;
157 os_info_old = NULL;
158}
159
160/*
161 * Return pointer to os infor entry and its size
162 */
163void *os_info_old_entry(int nr, unsigned long *size)
164{
165 os_info_old_init();
166
167 if (!os_info_old)
168 return NULL;
169 if (!os_info_old->entry[nr].addr)
170 return NULL;
171 *size = (unsigned long) os_info_old->entry[nr].size;
172 return (void *)(unsigned long)os_info_old->entry[nr].addr;
173}
174#endif