|
| 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 *par_header; |
| 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); |
0 commit comments