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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/lowcore.h>
17#include <asm/os_info.h>
18
19/*
20 * OS info structure has to be page aligned
21 */
22static struct os_info os_info __page_aligned_data;
23
24/*
25 * Compute checksum over OS info structure
26 */
27u32 os_info_csum(struct os_info *os_info)
28{
29 int size = sizeof(*os_info) - offsetof(struct os_info, version_major);
30 return (__force u32)csum_partial(&os_info->version_major, size, 0);
31}
32
33/*
34 * Add crashkernel info to OS info and update checksum
35 */
36void os_info_crashkernel_add(unsigned long base, unsigned long size)
37{
38 os_info.crashkernel_addr = (u64)(unsigned long)base;
39 os_info.crashkernel_size = (u64)(unsigned long)size;
40 os_info.csum = os_info_csum(&os_info);
41}
42
43/*
44 * Add OS info entry and update checksum
45 */
46void os_info_entry_add(int nr, void *ptr, u64 size)
47{
48 os_info.entry[nr].addr = (u64)(unsigned long)ptr;
49 os_info.entry[nr].size = size;
50 os_info.entry[nr].csum = (__force u32)csum_partial(ptr, size, 0);
51 os_info.csum = os_info_csum(&os_info);
52}
53
54/*
55 * Initialize OS info structure and set lowcore pointer
56 */
57void __init os_info_init(void)
58{
59 void *ptr = &os_info;
60
61 os_info.version_major = OS_INFO_VERSION_MAJOR;
62 os_info.version_minor = OS_INFO_VERSION_MINOR;
63 os_info.magic = OS_INFO_MAGIC;
64 os_info.csum = os_info_csum(&os_info);
65 mem_assign_absolute(S390_lowcore.os_info, (unsigned long) ptr);
66}
67
68#ifdef CONFIG_CRASH_DUMP
69
70static struct os_info *os_info_old;
71
72/*
73 * Allocate and copy OS info entry from oldmem
74 */
75static void os_info_old_alloc(int nr, int align)
76{
77 unsigned long addr, size = 0;
78 char *buf, *buf_align, *msg;
79 u32 csum;
80
81 addr = os_info_old->entry[nr].addr;
82 if (!addr) {
83 msg = "not available";
84 goto fail;
85 }
86 size = os_info_old->entry[nr].size;
87 buf = kmalloc(size + align - 1, GFP_KERNEL);
88 if (!buf) {
89 msg = "alloc failed";
90 goto fail;
91 }
92 buf_align = PTR_ALIGN(buf, align);
93 if (copy_oldmem_kernel(buf_align, (void *) addr, size)) {
94 msg = "copy failed";
95 goto fail_free;
96 }
97 csum = (__force u32)csum_partial(buf_align, size, 0);
98 if (csum != os_info_old->entry[nr].csum) {
99 msg = "checksum failed";
100 goto fail_free;
101 }
102 os_info_old->entry[nr].addr = (u64)(unsigned long)buf_align;
103 msg = "copied";
104 goto out;
105fail_free:
106 kfree(buf);
107fail:
108 os_info_old->entry[nr].addr = 0;
109out:
110 pr_info("entry %i: %s (addr=0x%lx size=%lu)\n",
111 nr, msg, addr, size);
112}
113
114/*
115 * Initialize os info and os info entries from oldmem
116 */
117static void os_info_old_init(void)
118{
119 static int os_info_init;
120 unsigned long addr;
121
122 if (os_info_init)
123 return;
124 if (!OLDMEM_BASE)
125 goto fail;
126 if (copy_oldmem_kernel(&addr, &S390_lowcore.os_info, sizeof(addr)))
127 goto fail;
128 if (addr == 0 || addr % PAGE_SIZE)
129 goto fail;
130 os_info_old = kzalloc(sizeof(*os_info_old), GFP_KERNEL);
131 if (!os_info_old)
132 goto fail;
133 if (copy_oldmem_kernel(os_info_old, (void *) addr,
134 sizeof(*os_info_old)))
135 goto fail_free;
136 if (os_info_old->magic != OS_INFO_MAGIC)
137 goto fail_free;
138 if (os_info_old->csum != os_info_csum(os_info_old))
139 goto fail_free;
140 if (os_info_old->version_major > OS_INFO_VERSION_MAJOR)
141 goto fail_free;
142 os_info_old_alloc(OS_INFO_VMCOREINFO, 1);
143 os_info_old_alloc(OS_INFO_REIPL_BLOCK, 1);
144 pr_info("crashkernel: addr=0x%lx size=%lu\n",
145 (unsigned long) os_info_old->crashkernel_addr,
146 (unsigned long) os_info_old->crashkernel_size);
147 os_info_init = 1;
148 return;
149fail_free:
150 kfree(os_info_old);
151fail:
152 os_info_init = 1;
153 os_info_old = NULL;
154}
155
156/*
157 * Return pointer to os infor entry and its size
158 */
159void *os_info_old_entry(int nr, unsigned long *size)
160{
161 os_info_old_init();
162
163 if (!os_info_old)
164 return NULL;
165 if (!os_info_old->entry[nr].addr)
166 return NULL;
167 *size = (unsigned long) os_info_old->entry[nr].size;
168 return (void *)(unsigned long)os_info_old->entry[nr].addr;
169}
170#endif