Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012 Google, Inc. |
| 3 | * |
| 4 | * This software is licensed under the terms of the GNU General Public |
| 5 | * License version 2, as published by the Free Software Foundation, and |
| 6 | * may be copied, distributed, and modified under those terms. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | * GNU General Public License for more details. |
| 12 | * |
| 13 | */ |
| 14 | |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 15 | #define pr_fmt(fmt) "persistent_ram: " fmt |
| 16 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 17 | #include <linux/device.h> |
| 18 | #include <linux/err.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 19 | #include <linux/errno.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 20 | #include <linux/init.h> |
| 21 | #include <linux/io.h> |
Mark Salyzyn | 5bf6d1b | 2016-09-01 08:13:46 -0700 | [diff] [blame] | 22 | #include <linux/kernel.h> |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 23 | #include <linux/list.h> |
| 24 | #include <linux/memblock.h> |
Mark Salyzyn | 5bf6d1b | 2016-09-01 08:13:46 -0700 | [diff] [blame] | 25 | #include <linux/pstore_ram.h> |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 26 | #include <linux/rslib.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 27 | #include <linux/slab.h> |
Mark Salyzyn | 5bf6d1b | 2016-09-01 08:13:46 -0700 | [diff] [blame] | 28 | #include <linux/uaccess.h> |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 29 | #include <linux/vmalloc.h> |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 30 | #include <asm/page.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 31 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 32 | struct persistent_ram_buffer { |
| 33 | uint32_t sig; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 34 | atomic_t start; |
| 35 | atomic_t size; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 36 | uint8_t data[0]; |
| 37 | }; |
| 38 | |
| 39 | #define PERSISTENT_RAM_SIG (0x43474244) /* DBGC */ |
| 40 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 41 | static inline size_t buffer_size(struct persistent_ram_zone *prz) |
| 42 | { |
| 43 | return atomic_read(&prz->buffer->size); |
| 44 | } |
| 45 | |
| 46 | static inline size_t buffer_start(struct persistent_ram_zone *prz) |
| 47 | { |
| 48 | return atomic_read(&prz->buffer->start); |
| 49 | } |
| 50 | |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 51 | /* increase and wrap the start pointer, returning the old value */ |
Sebastian Andrzej Siewior | d5a9bf0 | 2016-09-08 13:48:06 +0200 | [diff] [blame] | 52 | static size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a) |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 53 | { |
| 54 | int old; |
| 55 | int new; |
Joel Fernandes | 46930803 | 2016-10-20 00:34:01 -0700 | [diff] [blame] | 56 | unsigned long flags = 0; |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 57 | |
Joel Fernandes | 46930803 | 2016-10-20 00:34:01 -0700 | [diff] [blame] | 58 | if (!(prz->flags & PRZ_FLAG_NO_LOCK)) |
| 59 | raw_spin_lock_irqsave(&prz->buffer_lock, flags); |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 60 | |
| 61 | old = atomic_read(&prz->buffer->start); |
| 62 | new = old + a; |
Liu ShuoX | 017321c | 2014-03-12 21:24:44 +0800 | [diff] [blame] | 63 | while (unlikely(new >= prz->buffer_size)) |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 64 | new -= prz->buffer_size; |
| 65 | atomic_set(&prz->buffer->start, new); |
| 66 | |
Joel Fernandes | 46930803 | 2016-10-20 00:34:01 -0700 | [diff] [blame] | 67 | if (!(prz->flags & PRZ_FLAG_NO_LOCK)) |
| 68 | raw_spin_unlock_irqrestore(&prz->buffer_lock, flags); |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 69 | |
| 70 | return old; |
| 71 | } |
| 72 | |
| 73 | /* increase the size counter until it hits the max size */ |
Sebastian Andrzej Siewior | d5a9bf0 | 2016-09-08 13:48:06 +0200 | [diff] [blame] | 74 | static void buffer_size_add(struct persistent_ram_zone *prz, size_t a) |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 75 | { |
| 76 | size_t old; |
| 77 | size_t new; |
Joel Fernandes | 46930803 | 2016-10-20 00:34:01 -0700 | [diff] [blame] | 78 | unsigned long flags = 0; |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 79 | |
Joel Fernandes | 46930803 | 2016-10-20 00:34:01 -0700 | [diff] [blame] | 80 | if (!(prz->flags & PRZ_FLAG_NO_LOCK)) |
| 81 | raw_spin_lock_irqsave(&prz->buffer_lock, flags); |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 82 | |
| 83 | old = atomic_read(&prz->buffer->size); |
| 84 | if (old == prz->buffer_size) |
| 85 | goto exit; |
| 86 | |
| 87 | new = old + a; |
| 88 | if (new > prz->buffer_size) |
| 89 | new = prz->buffer_size; |
| 90 | atomic_set(&prz->buffer->size, new); |
| 91 | |
| 92 | exit: |
Joel Fernandes | 46930803 | 2016-10-20 00:34:01 -0700 | [diff] [blame] | 93 | if (!(prz->flags & PRZ_FLAG_NO_LOCK)) |
| 94 | raw_spin_unlock_irqrestore(&prz->buffer_lock, flags); |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 95 | } |
| 96 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 97 | static void notrace persistent_ram_encode_rs8(struct persistent_ram_zone *prz, |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 98 | uint8_t *data, size_t len, uint8_t *ecc) |
| 99 | { |
| 100 | int i; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 101 | uint16_t par[prz->ecc_info.ecc_size]; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 102 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 103 | /* Initialize the parity buffer */ |
| 104 | memset(par, 0, sizeof(par)); |
| 105 | encode_rs8(prz->rs_decoder, data, len, par, 0); |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 106 | for (i = 0; i < prz->ecc_info.ecc_size; i++) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 107 | ecc[i] = par[i]; |
| 108 | } |
| 109 | |
| 110 | static int persistent_ram_decode_rs8(struct persistent_ram_zone *prz, |
| 111 | void *data, size_t len, uint8_t *ecc) |
| 112 | { |
| 113 | int i; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 114 | uint16_t par[prz->ecc_info.ecc_size]; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 115 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 116 | for (i = 0; i < prz->ecc_info.ecc_size; i++) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 117 | par[i] = ecc[i]; |
| 118 | return decode_rs8(prz->rs_decoder, data, par, len, |
| 119 | NULL, 0, NULL, 0, NULL); |
| 120 | } |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 121 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 122 | static void notrace persistent_ram_update_ecc(struct persistent_ram_zone *prz, |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 123 | unsigned int start, unsigned int count) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 124 | { |
| 125 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 126 | uint8_t *buffer_end = buffer->data + prz->buffer_size; |
| 127 | uint8_t *block; |
| 128 | uint8_t *par; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 129 | int ecc_block_size = prz->ecc_info.block_size; |
| 130 | int ecc_size = prz->ecc_info.ecc_size; |
| 131 | int size = ecc_block_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 132 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 133 | if (!ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 134 | return; |
| 135 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 136 | block = buffer->data + (start & ~(ecc_block_size - 1)); |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 137 | par = prz->par_buffer + (start / ecc_block_size) * ecc_size; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 138 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 139 | do { |
| 140 | if (block + ecc_block_size > buffer_end) |
| 141 | size = buffer_end - block; |
| 142 | persistent_ram_encode_rs8(prz, block, size, par); |
| 143 | block += ecc_block_size; |
| 144 | par += ecc_size; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 145 | } while (block < buffer->data + start + count); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 146 | } |
| 147 | |
| 148 | static void persistent_ram_update_header_ecc(struct persistent_ram_zone *prz) |
| 149 | { |
| 150 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 151 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 152 | if (!prz->ecc_info.ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 153 | return; |
| 154 | |
| 155 | persistent_ram_encode_rs8(prz, (uint8_t *)buffer, sizeof(*buffer), |
| 156 | prz->par_header); |
| 157 | } |
| 158 | |
| 159 | static void persistent_ram_ecc_old(struct persistent_ram_zone *prz) |
| 160 | { |
| 161 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 162 | uint8_t *block; |
| 163 | uint8_t *par; |
| 164 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 165 | if (!prz->ecc_info.ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 166 | return; |
| 167 | |
| 168 | block = buffer->data; |
| 169 | par = prz->par_buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 170 | while (block < buffer->data + buffer_size(prz)) { |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 171 | int numerr; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 172 | int size = prz->ecc_info.block_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 173 | if (block + size > buffer->data + prz->buffer_size) |
| 174 | size = buffer->data + prz->buffer_size - block; |
| 175 | numerr = persistent_ram_decode_rs8(prz, block, size, par); |
| 176 | if (numerr > 0) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 177 | pr_devel("error in block %p, %d\n", block, numerr); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 178 | prz->corrected_bytes += numerr; |
| 179 | } else if (numerr < 0) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 180 | pr_devel("uncorrectable error in block %p\n", block); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 181 | prz->bad_blocks++; |
| 182 | } |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 183 | block += prz->ecc_info.block_size; |
| 184 | par += prz->ecc_info.ecc_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 185 | } |
| 186 | } |
| 187 | |
Anton Vorontsov | 5ca5d4e | 2012-07-09 17:03:19 -0700 | [diff] [blame] | 188 | static int persistent_ram_init_ecc(struct persistent_ram_zone *prz, |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 189 | struct persistent_ram_ecc_info *ecc_info) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 190 | { |
| 191 | int numerr; |
| 192 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 193 | int ecc_blocks; |
Anton Vorontsov | 1e6a9e5 | 2012-06-18 19:15:53 -0700 | [diff] [blame] | 194 | size_t ecc_total; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 195 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 196 | if (!ecc_info || !ecc_info->ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 197 | return 0; |
| 198 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 199 | prz->ecc_info.block_size = ecc_info->block_size ?: 128; |
| 200 | prz->ecc_info.ecc_size = ecc_info->ecc_size ?: 16; |
| 201 | prz->ecc_info.symsize = ecc_info->symsize ?: 8; |
| 202 | prz->ecc_info.poly = ecc_info->poly ?: 0x11d; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 203 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 204 | ecc_blocks = DIV_ROUND_UP(prz->buffer_size - prz->ecc_info.ecc_size, |
| 205 | prz->ecc_info.block_size + |
| 206 | prz->ecc_info.ecc_size); |
| 207 | ecc_total = (ecc_blocks + 1) * prz->ecc_info.ecc_size; |
Anton Vorontsov | 1e6a9e5 | 2012-06-18 19:15:53 -0700 | [diff] [blame] | 208 | if (ecc_total >= prz->buffer_size) { |
| 209 | pr_err("%s: invalid ecc_size %u (total %zu, buffer size %zu)\n", |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 210 | __func__, prz->ecc_info.ecc_size, |
| 211 | ecc_total, prz->buffer_size); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 212 | return -EINVAL; |
| 213 | } |
| 214 | |
Anton Vorontsov | 1e6a9e5 | 2012-06-18 19:15:53 -0700 | [diff] [blame] | 215 | prz->buffer_size -= ecc_total; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 216 | prz->par_buffer = buffer->data + prz->buffer_size; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 217 | prz->par_header = prz->par_buffer + |
| 218 | ecc_blocks * prz->ecc_info.ecc_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 219 | |
| 220 | /* |
| 221 | * first consecutive root is 0 |
| 222 | * primitive element to generate roots = 1 |
| 223 | */ |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 224 | prz->rs_decoder = init_rs(prz->ecc_info.symsize, prz->ecc_info.poly, |
| 225 | 0, 1, prz->ecc_info.ecc_size); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 226 | if (prz->rs_decoder == NULL) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 227 | pr_info("init_rs failed\n"); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 228 | return -EINVAL; |
| 229 | } |
| 230 | |
| 231 | prz->corrected_bytes = 0; |
| 232 | prz->bad_blocks = 0; |
| 233 | |
| 234 | numerr = persistent_ram_decode_rs8(prz, buffer, sizeof(*buffer), |
| 235 | prz->par_header); |
| 236 | if (numerr > 0) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 237 | pr_info("error in header, %d\n", numerr); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 238 | prz->corrected_bytes += numerr; |
| 239 | } else if (numerr < 0) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 240 | pr_info("uncorrectable error in header\n"); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 241 | prz->bad_blocks++; |
| 242 | } |
| 243 | |
| 244 | return 0; |
| 245 | } |
| 246 | |
| 247 | ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz, |
| 248 | char *str, size_t len) |
| 249 | { |
| 250 | ssize_t ret; |
| 251 | |
Arve Hjønnevåg | bd08ec3 | 2012-12-05 21:19:51 -0800 | [diff] [blame] | 252 | if (!prz->ecc_info.ecc_size) |
| 253 | return 0; |
| 254 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 255 | if (prz->corrected_bytes || prz->bad_blocks) |
| 256 | ret = snprintf(str, len, "" |
| 257 | "\n%d Corrected bytes, %d unrecoverable blocks\n", |
| 258 | prz->corrected_bytes, prz->bad_blocks); |
| 259 | else |
| 260 | ret = snprintf(str, len, "\nNo errors detected\n"); |
| 261 | |
| 262 | return ret; |
| 263 | } |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 264 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 265 | static void notrace persistent_ram_update(struct persistent_ram_zone *prz, |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 266 | const void *s, unsigned int start, unsigned int count) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 267 | { |
| 268 | struct persistent_ram_buffer *buffer = prz->buffer; |
Furquan Shaikh | 7e75678 | 2016-02-15 09:19:48 +0100 | [diff] [blame] | 269 | memcpy_toio(buffer->data + start, s, count); |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 270 | persistent_ram_update_ecc(prz, start, count); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 271 | } |
| 272 | |
Mark Salyzyn | 5bf6d1b | 2016-09-01 08:13:46 -0700 | [diff] [blame] | 273 | static int notrace persistent_ram_update_user(struct persistent_ram_zone *prz, |
| 274 | const void __user *s, unsigned int start, unsigned int count) |
| 275 | { |
| 276 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 277 | int ret = unlikely(__copy_from_user(buffer->data + start, s, count)) ? |
| 278 | -EFAULT : 0; |
| 279 | persistent_ram_update_ecc(prz, start, count); |
| 280 | return ret; |
| 281 | } |
| 282 | |
Anton Vorontsov | 201e4ac | 2012-05-26 06:07:49 -0700 | [diff] [blame] | 283 | void persistent_ram_save_old(struct persistent_ram_zone *prz) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 284 | { |
| 285 | struct persistent_ram_buffer *buffer = prz->buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 286 | size_t size = buffer_size(prz); |
| 287 | size_t start = buffer_start(prz); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 288 | |
Anton Vorontsov | 201e4ac | 2012-05-26 06:07:49 -0700 | [diff] [blame] | 289 | if (!size) |
| 290 | return; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 291 | |
Anton Vorontsov | 201e4ac | 2012-05-26 06:07:49 -0700 | [diff] [blame] | 292 | if (!prz->old_log) { |
| 293 | persistent_ram_ecc_old(prz); |
| 294 | prz->old_log = kmalloc(size, GFP_KERNEL); |
| 295 | } |
| 296 | if (!prz->old_log) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 297 | pr_err("failed to allocate buffer\n"); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 298 | return; |
| 299 | } |
| 300 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 301 | prz->old_log_size = size; |
Andrew Bresticker | d771fdf | 2016-02-15 09:19:49 +0100 | [diff] [blame] | 302 | memcpy_fromio(prz->old_log, &buffer->data[start], size - start); |
| 303 | memcpy_fromio(prz->old_log + size - start, &buffer->data[0], start); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 304 | } |
| 305 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 306 | int notrace persistent_ram_write(struct persistent_ram_zone *prz, |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 307 | const void *s, unsigned int count) |
| 308 | { |
| 309 | int rem; |
| 310 | int c = count; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 311 | size_t start; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 312 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 313 | if (unlikely(c > prz->buffer_size)) { |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 314 | s += c - prz->buffer_size; |
| 315 | c = prz->buffer_size; |
| 316 | } |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 317 | |
Anton Vorontsov | 484dd30 | 2012-05-11 17:17:17 -0700 | [diff] [blame] | 318 | buffer_size_add(prz, c); |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 319 | |
| 320 | start = buffer_start_add(prz, c); |
| 321 | |
| 322 | rem = prz->buffer_size - start; |
| 323 | if (unlikely(rem < c)) { |
| 324 | persistent_ram_update(prz, s, start, rem); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 325 | s += rem; |
| 326 | c -= rem; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 327 | start = 0; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 328 | } |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 329 | persistent_ram_update(prz, s, start, c); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 330 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 331 | persistent_ram_update_header_ecc(prz); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 332 | |
| 333 | return count; |
| 334 | } |
| 335 | |
Mark Salyzyn | 5bf6d1b | 2016-09-01 08:13:46 -0700 | [diff] [blame] | 336 | int notrace persistent_ram_write_user(struct persistent_ram_zone *prz, |
| 337 | const void __user *s, unsigned int count) |
| 338 | { |
| 339 | int rem, ret = 0, c = count; |
| 340 | size_t start; |
| 341 | |
| 342 | if (unlikely(!access_ok(VERIFY_READ, s, count))) |
| 343 | return -EFAULT; |
| 344 | if (unlikely(c > prz->buffer_size)) { |
| 345 | s += c - prz->buffer_size; |
| 346 | c = prz->buffer_size; |
| 347 | } |
| 348 | |
| 349 | buffer_size_add(prz, c); |
| 350 | |
| 351 | start = buffer_start_add(prz, c); |
| 352 | |
| 353 | rem = prz->buffer_size - start; |
| 354 | if (unlikely(rem < c)) { |
| 355 | ret = persistent_ram_update_user(prz, s, start, rem); |
| 356 | s += rem; |
| 357 | c -= rem; |
| 358 | start = 0; |
| 359 | } |
| 360 | if (likely(!ret)) |
| 361 | ret = persistent_ram_update_user(prz, s, start, c); |
| 362 | |
| 363 | persistent_ram_update_header_ecc(prz); |
| 364 | |
| 365 | return unlikely(ret) ? ret : count; |
| 366 | } |
| 367 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 368 | size_t persistent_ram_old_size(struct persistent_ram_zone *prz) |
| 369 | { |
| 370 | return prz->old_log_size; |
| 371 | } |
| 372 | |
| 373 | void *persistent_ram_old(struct persistent_ram_zone *prz) |
| 374 | { |
| 375 | return prz->old_log; |
| 376 | } |
| 377 | |
| 378 | void persistent_ram_free_old(struct persistent_ram_zone *prz) |
| 379 | { |
| 380 | kfree(prz->old_log); |
| 381 | prz->old_log = NULL; |
| 382 | prz->old_log_size = 0; |
| 383 | } |
| 384 | |
Anton Vorontsov | fce3979 | 2012-05-26 06:07:51 -0700 | [diff] [blame] | 385 | void persistent_ram_zap(struct persistent_ram_zone *prz) |
| 386 | { |
| 387 | atomic_set(&prz->buffer->start, 0); |
| 388 | atomic_set(&prz->buffer->size, 0); |
| 389 | persistent_ram_update_header_ecc(prz); |
| 390 | } |
| 391 | |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 392 | static void *persistent_ram_vmap(phys_addr_t start, size_t size, |
| 393 | unsigned int memtype) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 394 | { |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 395 | struct page **pages; |
| 396 | phys_addr_t page_start; |
| 397 | unsigned int page_count; |
| 398 | pgprot_t prot; |
| 399 | unsigned int i; |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 400 | void *vaddr; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 401 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 402 | page_start = start - offset_in_page(start); |
| 403 | page_count = DIV_ROUND_UP(size + offset_in_page(start), PAGE_SIZE); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 404 | |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 405 | if (memtype) |
| 406 | prot = pgprot_noncached(PAGE_KERNEL); |
| 407 | else |
| 408 | prot = pgprot_writecombine(PAGE_KERNEL); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 409 | |
Fabian Frederick | b8f52d8 | 2014-08-08 14:22:35 -0700 | [diff] [blame] | 410 | pages = kmalloc_array(page_count, sizeof(struct page *), GFP_KERNEL); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 411 | if (!pages) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 412 | pr_err("%s: Failed to allocate array for %u pages\n", |
| 413 | __func__, page_count); |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 414 | return NULL; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 415 | } |
| 416 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 417 | for (i = 0; i < page_count; i++) { |
| 418 | phys_addr_t addr = page_start + i * PAGE_SIZE; |
| 419 | pages[i] = pfn_to_page(addr >> PAGE_SHIFT); |
| 420 | } |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 421 | vaddr = vmap(pages, page_count, VM_MAP, prot); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 422 | kfree(pages); |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 423 | |
Bin Yang | 7026e24 | 2018-09-12 03:36:34 +0000 | [diff] [blame] | 424 | /* |
| 425 | * Since vmap() uses page granularity, we must add the offset |
| 426 | * into the page here, to get the byte granularity address |
| 427 | * into the mapping to represent the actual "start" location. |
| 428 | */ |
| 429 | return vaddr + offset_in_page(start); |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 430 | } |
| 431 | |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 432 | static void *persistent_ram_iomap(phys_addr_t start, size_t size, |
| 433 | unsigned int memtype) |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 434 | { |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 435 | void *va; |
| 436 | |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 437 | if (!request_mem_region(start, size, "persistent_ram")) { |
| 438 | pr_err("request mem region (0x%llx@0x%llx) failed\n", |
| 439 | (unsigned long long)size, (unsigned long long)start); |
| 440 | return NULL; |
| 441 | } |
| 442 | |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 443 | if (memtype) |
| 444 | va = ioremap(start, size); |
| 445 | else |
| 446 | va = ioremap_wc(start, size); |
| 447 | |
Bin Yang | 7026e24 | 2018-09-12 03:36:34 +0000 | [diff] [blame] | 448 | /* |
| 449 | * Since request_mem_region() and ioremap() are byte-granularity |
| 450 | * there is no need handle anything special like we do when the |
| 451 | * vmap() case in persistent_ram_vmap() above. |
| 452 | */ |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 453 | return va; |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 454 | } |
| 455 | |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 456 | static int persistent_ram_buffer_map(phys_addr_t start, phys_addr_t size, |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 457 | struct persistent_ram_zone *prz, int memtype) |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 458 | { |
Anton Vorontsov | d3b4876 | 2012-05-11 17:18:05 -0700 | [diff] [blame] | 459 | prz->paddr = start; |
| 460 | prz->size = size; |
| 461 | |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 462 | if (pfn_valid(start >> PAGE_SHIFT)) |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 463 | prz->vaddr = persistent_ram_vmap(start, size, memtype); |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 464 | else |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 465 | prz->vaddr = persistent_ram_iomap(start, size, memtype); |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 466 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 467 | if (!prz->vaddr) { |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 468 | pr_err("%s: Failed to map 0x%llx pages at 0x%llx\n", __func__, |
| 469 | (unsigned long long)size, (unsigned long long)start); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 470 | return -ENOMEM; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 471 | } |
| 472 | |
Bin Yang | 7026e24 | 2018-09-12 03:36:34 +0000 | [diff] [blame] | 473 | prz->buffer = prz->vaddr; |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 474 | prz->buffer_size = size - sizeof(struct persistent_ram_buffer); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 475 | |
| 476 | return 0; |
| 477 | } |
| 478 | |
Greg Kroah-Hartman | f568f6c | 2012-12-21 15:02:05 -0800 | [diff] [blame] | 479 | static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig, |
Kees Cook | a084027 | 2017-02-09 15:43:44 -0800 | [diff] [blame] | 480 | struct persistent_ram_ecc_info *ecc_info) |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 481 | { |
Anton Vorontsov | bb4206f | 2012-05-11 17:17:25 -0700 | [diff] [blame] | 482 | int ret; |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 483 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 484 | ret = persistent_ram_init_ecc(prz, ecc_info); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 485 | if (ret) |
Anton Vorontsov | bb4206f | 2012-05-11 17:17:25 -0700 | [diff] [blame] | 486 | return ret; |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 487 | |
Anton Vorontsov | cbe7cbf | 2012-07-17 12:11:12 -0700 | [diff] [blame] | 488 | sig ^= PERSISTENT_RAM_SIG; |
| 489 | |
| 490 | if (prz->buffer->sig == sig) { |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 491 | if (buffer_size(prz) > prz->buffer_size || |
| 492 | buffer_start(prz) > buffer_size(prz)) |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 493 | pr_info("found existing invalid buffer, size %zu, start %zu\n", |
| 494 | buffer_size(prz), buffer_start(prz)); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 495 | else { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 496 | pr_debug("found existing buffer, size %zu, start %zu\n", |
| 497 | buffer_size(prz), buffer_start(prz)); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 498 | persistent_ram_save_old(prz); |
Anton Vorontsov | 25b63da | 2012-05-26 06:07:50 -0700 | [diff] [blame] | 499 | return 0; |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 500 | } |
| 501 | } else { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 502 | pr_debug("no valid data in buffer (sig = 0x%08x)\n", |
| 503 | prz->buffer->sig); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 504 | } |
| 505 | |
Kees Cook | a084027 | 2017-02-09 15:43:44 -0800 | [diff] [blame] | 506 | /* Rewind missing or invalid memory area. */ |
Anton Vorontsov | cbe7cbf | 2012-07-17 12:11:12 -0700 | [diff] [blame] | 507 | prz->buffer->sig = sig; |
Anton Vorontsov | fce3979 | 2012-05-26 06:07:51 -0700 | [diff] [blame] | 508 | persistent_ram_zap(prz); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 509 | |
Anton Vorontsov | bb4206f | 2012-05-11 17:17:25 -0700 | [diff] [blame] | 510 | return 0; |
| 511 | } |
| 512 | |
Anton Vorontsov | d3b4876 | 2012-05-11 17:18:05 -0700 | [diff] [blame] | 513 | void persistent_ram_free(struct persistent_ram_zone *prz) |
| 514 | { |
Anton Vorontsov | beeb943 | 2012-06-18 19:15:52 -0700 | [diff] [blame] | 515 | if (!prz) |
| 516 | return; |
| 517 | |
| 518 | if (prz->vaddr) { |
| 519 | if (pfn_valid(prz->paddr >> PAGE_SHIFT)) { |
Bin Yang | 7026e24 | 2018-09-12 03:36:34 +0000 | [diff] [blame] | 520 | /* We must vunmap() at page-granularity. */ |
| 521 | vunmap(prz->vaddr - offset_in_page(prz->paddr)); |
Anton Vorontsov | beeb943 | 2012-06-18 19:15:52 -0700 | [diff] [blame] | 522 | } else { |
| 523 | iounmap(prz->vaddr); |
| 524 | release_mem_region(prz->paddr, prz->size); |
| 525 | } |
| 526 | prz->vaddr = NULL; |
Anton Vorontsov | d3b4876 | 2012-05-11 17:18:05 -0700 | [diff] [blame] | 527 | } |
| 528 | persistent_ram_free_old(prz); |
| 529 | kfree(prz); |
| 530 | } |
| 531 | |
Greg Kroah-Hartman | f568f6c | 2012-12-21 15:02:05 -0800 | [diff] [blame] | 532 | struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size, |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 533 | u32 sig, struct persistent_ram_ecc_info *ecc_info, |
Joel Fernandes | 46930803 | 2016-10-20 00:34:01 -0700 | [diff] [blame] | 534 | unsigned int memtype, u32 flags) |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 535 | { |
| 536 | struct persistent_ram_zone *prz; |
| 537 | int ret = -ENOMEM; |
| 538 | |
| 539 | prz = kzalloc(sizeof(struct persistent_ram_zone), GFP_KERNEL); |
| 540 | if (!prz) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 541 | pr_err("failed to allocate persistent ram zone\n"); |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 542 | goto err; |
| 543 | } |
| 544 | |
Kees Cook | a084027 | 2017-02-09 15:43:44 -0800 | [diff] [blame] | 545 | /* Initialize general buffer state. */ |
Kees Cook | e10f7bd | 2017-03-05 22:08:58 -0800 | [diff] [blame] | 546 | raw_spin_lock_init(&prz->buffer_lock); |
Kees Cook | a084027 | 2017-02-09 15:43:44 -0800 | [diff] [blame] | 547 | prz->flags = flags; |
| 548 | |
Tony Lindgren | 027bc8b | 2014-09-16 13:50:01 -0700 | [diff] [blame] | 549 | ret = persistent_ram_buffer_map(start, size, prz, memtype); |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 550 | if (ret) |
| 551 | goto err; |
| 552 | |
Kees Cook | a084027 | 2017-02-09 15:43:44 -0800 | [diff] [blame] | 553 | ret = persistent_ram_post_init(prz, sig, ecc_info); |
Anton Vorontsov | beeb943 | 2012-06-18 19:15:52 -0700 | [diff] [blame] | 554 | if (ret) |
| 555 | goto err; |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 556 | |
| 557 | return prz; |
| 558 | err: |
Anton Vorontsov | beeb943 | 2012-06-18 19:15:52 -0700 | [diff] [blame] | 559 | persistent_ram_free(prz); |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 560 | return ERR_PTR(ret); |
| 561 | } |