1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com> |
4 | * Copyright (C) 2011 Kees Cook <keescook@chromium.org> |
5 | * Copyright (C) 2011 Google, Inc. |
6 | */ |
7 | |
8 | #include <linux/pstore_ram.h> |
9 | |
10 | /* |
11 | * Choose whether access to the RAM zone requires locking or not. If a zone |
12 | * can be written to from different CPUs like with ftrace for example, then |
13 | * PRZ_FLAG_NO_LOCK is used. For all other cases, locking is required. |
14 | */ |
15 | #define PRZ_FLAG_NO_LOCK BIT(0) |
16 | /* |
17 | * If a PRZ should only have a single-boot lifetime, this marks it as |
18 | * getting wiped after its contents get copied out after boot. |
19 | */ |
20 | #define PRZ_FLAG_ZAP_OLD BIT(1) |
21 | |
22 | /** |
23 | * struct persistent_ram_zone - Details of a persistent RAM zone (PRZ) |
24 | * used as a pstore backend |
25 | * |
26 | * @paddr: physical address of the mapped RAM area |
27 | * @size: size of mapping |
28 | * @label: unique name of this PRZ |
29 | * @type: frontend type for this PRZ |
30 | * @flags: holds PRZ_FLAGS_* bits |
31 | * |
32 | * @buffer_lock: |
33 | * locks access to @buffer "size" bytes and "start" offset |
34 | * @buffer: |
35 | * pointer to actual RAM area managed by this PRZ |
36 | * @buffer_size: |
37 | * bytes in @buffer->data (not including any trailing ECC bytes) |
38 | * |
39 | * @par_buffer: |
40 | * pointer into @buffer->data containing ECC bytes for @buffer->data |
41 | * @par_header: |
42 | * pointer into @buffer->data containing ECC bytes for @buffer header |
43 | * (i.e. all fields up to @data) |
44 | * @rs_decoder: |
45 | * RSLIB instance for doing ECC calculations |
46 | * @corrected_bytes: |
47 | * ECC corrected bytes accounting since boot |
48 | * @bad_blocks: |
49 | * ECC uncorrectable bytes accounting since boot |
50 | * @ecc_info: |
51 | * ECC configuration details |
52 | * |
53 | * @old_log: |
54 | * saved copy of @buffer->data prior to most recent wipe |
55 | * @old_log_size: |
56 | * bytes contained in @old_log |
57 | * |
58 | */ |
59 | struct persistent_ram_zone { |
60 | phys_addr_t paddr; |
61 | size_t size; |
62 | void *vaddr; |
63 | char *label; |
64 | enum pstore_type_id type; |
65 | u32 flags; |
66 | |
67 | raw_spinlock_t buffer_lock; |
68 | struct persistent_ram_buffer *buffer; |
69 | size_t buffer_size; |
70 | |
71 | char *par_buffer; |
72 | char *; |
73 | struct rs_control *rs_decoder; |
74 | int corrected_bytes; |
75 | int bad_blocks; |
76 | struct persistent_ram_ecc_info ecc_info; |
77 | |
78 | char *old_log; |
79 | size_t old_log_size; |
80 | }; |
81 | |
82 | struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size, |
83 | u32 sig, struct persistent_ram_ecc_info *ecc_info, |
84 | unsigned int memtype, u32 flags, char *label); |
85 | void persistent_ram_free(struct persistent_ram_zone **_prz); |
86 | void persistent_ram_zap(struct persistent_ram_zone *prz); |
87 | |
88 | int persistent_ram_write(struct persistent_ram_zone *prz, const void *s, |
89 | unsigned int count); |
90 | int persistent_ram_write_user(struct persistent_ram_zone *prz, |
91 | const void __user *s, unsigned int count); |
92 | |
93 | void persistent_ram_save_old(struct persistent_ram_zone *prz); |
94 | size_t persistent_ram_old_size(struct persistent_ram_zone *prz); |
95 | void *persistent_ram_old(struct persistent_ram_zone *prz); |
96 | void persistent_ram_free_old(struct persistent_ram_zone *prz); |
97 | ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz, |
98 | char *str, size_t len); |
99 | |