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> |
| 20 | #include <linux/kernel.h> |
| 21 | #include <linux/init.h> |
| 22 | #include <linux/io.h> |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 23 | #include <linux/list.h> |
| 24 | #include <linux/memblock.h> |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 25 | #include <linux/rslib.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 26 | #include <linux/slab.h> |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 27 | #include <linux/vmalloc.h> |
Anton Vorontsov | cddb875 | 2012-05-17 00:15:08 -0700 | [diff] [blame] | 28 | #include <linux/pstore_ram.h> |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 29 | #include <asm/page.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 30 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 31 | struct persistent_ram_buffer { |
| 32 | uint32_t sig; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 33 | atomic_t start; |
| 34 | atomic_t size; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 35 | uint8_t data[0]; |
| 36 | }; |
| 37 | |
| 38 | #define PERSISTENT_RAM_SIG (0x43474244) /* DBGC */ |
| 39 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 40 | static inline size_t buffer_size(struct persistent_ram_zone *prz) |
| 41 | { |
| 42 | return atomic_read(&prz->buffer->size); |
| 43 | } |
| 44 | |
| 45 | static inline size_t buffer_start(struct persistent_ram_zone *prz) |
| 46 | { |
| 47 | return atomic_read(&prz->buffer->start); |
| 48 | } |
| 49 | |
| 50 | /* increase and wrap the start pointer, returning the old value */ |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 51 | static size_t buffer_start_add_atomic(struct persistent_ram_zone *prz, size_t a) |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 52 | { |
| 53 | int old; |
| 54 | int new; |
| 55 | |
| 56 | do { |
| 57 | old = atomic_read(&prz->buffer->start); |
| 58 | new = old + a; |
Liu ShuoX | 017321c | 2014-03-12 21:24:44 +0800 | [diff] [blame] | 59 | while (unlikely(new >= prz->buffer_size)) |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 60 | new -= prz->buffer_size; |
| 61 | } while (atomic_cmpxchg(&prz->buffer->start, old, new) != old); |
| 62 | |
| 63 | return old; |
| 64 | } |
| 65 | |
| 66 | /* increase the size counter until it hits the max size */ |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 67 | static void buffer_size_add_atomic(struct persistent_ram_zone *prz, size_t a) |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 68 | { |
| 69 | size_t old; |
| 70 | size_t new; |
| 71 | |
| 72 | if (atomic_read(&prz->buffer->size) == prz->buffer_size) |
| 73 | return; |
| 74 | |
| 75 | do { |
| 76 | old = atomic_read(&prz->buffer->size); |
| 77 | new = old + a; |
| 78 | if (new > prz->buffer_size) |
| 79 | new = prz->buffer_size; |
| 80 | } while (atomic_cmpxchg(&prz->buffer->size, old, new) != old); |
| 81 | } |
| 82 | |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 83 | static DEFINE_RAW_SPINLOCK(buffer_lock); |
| 84 | |
| 85 | /* increase and wrap the start pointer, returning the old value */ |
| 86 | static size_t buffer_start_add_locked(struct persistent_ram_zone *prz, size_t a) |
| 87 | { |
| 88 | int old; |
| 89 | int new; |
| 90 | unsigned long flags; |
| 91 | |
| 92 | raw_spin_lock_irqsave(&buffer_lock, flags); |
| 93 | |
| 94 | old = atomic_read(&prz->buffer->start); |
| 95 | new = old + a; |
Liu ShuoX | 017321c | 2014-03-12 21:24:44 +0800 | [diff] [blame] | 96 | while (unlikely(new >= prz->buffer_size)) |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 97 | new -= prz->buffer_size; |
| 98 | atomic_set(&prz->buffer->start, new); |
| 99 | |
| 100 | raw_spin_unlock_irqrestore(&buffer_lock, flags); |
| 101 | |
| 102 | return old; |
| 103 | } |
| 104 | |
| 105 | /* increase the size counter until it hits the max size */ |
| 106 | static void buffer_size_add_locked(struct persistent_ram_zone *prz, size_t a) |
| 107 | { |
| 108 | size_t old; |
| 109 | size_t new; |
| 110 | unsigned long flags; |
| 111 | |
| 112 | raw_spin_lock_irqsave(&buffer_lock, flags); |
| 113 | |
| 114 | old = atomic_read(&prz->buffer->size); |
| 115 | if (old == prz->buffer_size) |
| 116 | goto exit; |
| 117 | |
| 118 | new = old + a; |
| 119 | if (new > prz->buffer_size) |
| 120 | new = prz->buffer_size; |
| 121 | atomic_set(&prz->buffer->size, new); |
| 122 | |
| 123 | exit: |
| 124 | raw_spin_unlock_irqrestore(&buffer_lock, flags); |
| 125 | } |
| 126 | |
| 127 | static size_t (*buffer_start_add)(struct persistent_ram_zone *, size_t) = buffer_start_add_atomic; |
| 128 | static void (*buffer_size_add)(struct persistent_ram_zone *, size_t) = buffer_size_add_atomic; |
| 129 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 130 | static void notrace persistent_ram_encode_rs8(struct persistent_ram_zone *prz, |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 131 | uint8_t *data, size_t len, uint8_t *ecc) |
| 132 | { |
| 133 | int i; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 134 | uint16_t par[prz->ecc_info.ecc_size]; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 135 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 136 | /* Initialize the parity buffer */ |
| 137 | memset(par, 0, sizeof(par)); |
| 138 | encode_rs8(prz->rs_decoder, data, len, par, 0); |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 139 | for (i = 0; i < prz->ecc_info.ecc_size; i++) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 140 | ecc[i] = par[i]; |
| 141 | } |
| 142 | |
| 143 | static int persistent_ram_decode_rs8(struct persistent_ram_zone *prz, |
| 144 | void *data, size_t len, uint8_t *ecc) |
| 145 | { |
| 146 | int i; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 147 | uint16_t par[prz->ecc_info.ecc_size]; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 148 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 149 | for (i = 0; i < prz->ecc_info.ecc_size; i++) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 150 | par[i] = ecc[i]; |
| 151 | return decode_rs8(prz->rs_decoder, data, par, len, |
| 152 | NULL, 0, NULL, 0, NULL); |
| 153 | } |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 154 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 155 | static void notrace persistent_ram_update_ecc(struct persistent_ram_zone *prz, |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 156 | unsigned int start, unsigned int count) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 157 | { |
| 158 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 159 | uint8_t *buffer_end = buffer->data + prz->buffer_size; |
| 160 | uint8_t *block; |
| 161 | uint8_t *par; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 162 | int ecc_block_size = prz->ecc_info.block_size; |
| 163 | int ecc_size = prz->ecc_info.ecc_size; |
| 164 | int size = ecc_block_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 165 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 166 | if (!ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 167 | return; |
| 168 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 169 | block = buffer->data + (start & ~(ecc_block_size - 1)); |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 170 | par = prz->par_buffer + (start / ecc_block_size) * ecc_size; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 171 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 172 | do { |
| 173 | if (block + ecc_block_size > buffer_end) |
| 174 | size = buffer_end - block; |
| 175 | persistent_ram_encode_rs8(prz, block, size, par); |
| 176 | block += ecc_block_size; |
| 177 | par += ecc_size; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 178 | } while (block < buffer->data + start + count); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 179 | } |
| 180 | |
| 181 | static void persistent_ram_update_header_ecc(struct persistent_ram_zone *prz) |
| 182 | { |
| 183 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 184 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 185 | if (!prz->ecc_info.ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 186 | return; |
| 187 | |
| 188 | persistent_ram_encode_rs8(prz, (uint8_t *)buffer, sizeof(*buffer), |
| 189 | prz->par_header); |
| 190 | } |
| 191 | |
| 192 | static void persistent_ram_ecc_old(struct persistent_ram_zone *prz) |
| 193 | { |
| 194 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 195 | uint8_t *block; |
| 196 | uint8_t *par; |
| 197 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 198 | if (!prz->ecc_info.ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 199 | return; |
| 200 | |
| 201 | block = buffer->data; |
| 202 | par = prz->par_buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 203 | while (block < buffer->data + buffer_size(prz)) { |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 204 | int numerr; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 205 | int size = prz->ecc_info.block_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 206 | if (block + size > buffer->data + prz->buffer_size) |
| 207 | size = buffer->data + prz->buffer_size - block; |
| 208 | numerr = persistent_ram_decode_rs8(prz, block, size, par); |
| 209 | if (numerr > 0) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 210 | pr_devel("error in block %p, %d\n", block, numerr); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 211 | prz->corrected_bytes += numerr; |
| 212 | } else if (numerr < 0) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 213 | pr_devel("uncorrectable error in block %p\n", block); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 214 | prz->bad_blocks++; |
| 215 | } |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 216 | block += prz->ecc_info.block_size; |
| 217 | par += prz->ecc_info.ecc_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 218 | } |
| 219 | } |
| 220 | |
Anton Vorontsov | 5ca5d4e | 2012-07-09 17:03:19 -0700 | [diff] [blame] | 221 | static int persistent_ram_init_ecc(struct persistent_ram_zone *prz, |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 222 | struct persistent_ram_ecc_info *ecc_info) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 223 | { |
| 224 | int numerr; |
| 225 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 226 | int ecc_blocks; |
Anton Vorontsov | 1e6a9e5 | 2012-06-18 19:15:53 -0700 | [diff] [blame] | 227 | size_t ecc_total; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 228 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 229 | if (!ecc_info || !ecc_info->ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 230 | return 0; |
| 231 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 232 | prz->ecc_info.block_size = ecc_info->block_size ?: 128; |
| 233 | prz->ecc_info.ecc_size = ecc_info->ecc_size ?: 16; |
| 234 | prz->ecc_info.symsize = ecc_info->symsize ?: 8; |
| 235 | prz->ecc_info.poly = ecc_info->poly ?: 0x11d; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 236 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 237 | ecc_blocks = DIV_ROUND_UP(prz->buffer_size - prz->ecc_info.ecc_size, |
| 238 | prz->ecc_info.block_size + |
| 239 | prz->ecc_info.ecc_size); |
| 240 | ecc_total = (ecc_blocks + 1) * prz->ecc_info.ecc_size; |
Anton Vorontsov | 1e6a9e5 | 2012-06-18 19:15:53 -0700 | [diff] [blame] | 241 | if (ecc_total >= prz->buffer_size) { |
| 242 | 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] | 243 | __func__, prz->ecc_info.ecc_size, |
| 244 | ecc_total, prz->buffer_size); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 245 | return -EINVAL; |
| 246 | } |
| 247 | |
Anton Vorontsov | 1e6a9e5 | 2012-06-18 19:15:53 -0700 | [diff] [blame] | 248 | prz->buffer_size -= ecc_total; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 249 | prz->par_buffer = buffer->data + prz->buffer_size; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 250 | prz->par_header = prz->par_buffer + |
| 251 | ecc_blocks * prz->ecc_info.ecc_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 252 | |
| 253 | /* |
| 254 | * first consecutive root is 0 |
| 255 | * primitive element to generate roots = 1 |
| 256 | */ |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 257 | prz->rs_decoder = init_rs(prz->ecc_info.symsize, prz->ecc_info.poly, |
| 258 | 0, 1, prz->ecc_info.ecc_size); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 259 | if (prz->rs_decoder == NULL) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 260 | pr_info("init_rs failed\n"); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 261 | return -EINVAL; |
| 262 | } |
| 263 | |
| 264 | prz->corrected_bytes = 0; |
| 265 | prz->bad_blocks = 0; |
| 266 | |
| 267 | numerr = persistent_ram_decode_rs8(prz, buffer, sizeof(*buffer), |
| 268 | prz->par_header); |
| 269 | if (numerr > 0) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 270 | pr_info("error in header, %d\n", numerr); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 271 | prz->corrected_bytes += numerr; |
| 272 | } else if (numerr < 0) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 273 | pr_info("uncorrectable error in header\n"); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 274 | prz->bad_blocks++; |
| 275 | } |
| 276 | |
| 277 | return 0; |
| 278 | } |
| 279 | |
| 280 | ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz, |
| 281 | char *str, size_t len) |
| 282 | { |
| 283 | ssize_t ret; |
| 284 | |
Arve Hjønnevåg | bd08ec3 | 2012-12-05 21:19:51 -0800 | [diff] [blame] | 285 | if (!prz->ecc_info.ecc_size) |
| 286 | return 0; |
| 287 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 288 | if (prz->corrected_bytes || prz->bad_blocks) |
| 289 | ret = snprintf(str, len, "" |
| 290 | "\n%d Corrected bytes, %d unrecoverable blocks\n", |
| 291 | prz->corrected_bytes, prz->bad_blocks); |
| 292 | else |
| 293 | ret = snprintf(str, len, "\nNo errors detected\n"); |
| 294 | |
| 295 | return ret; |
| 296 | } |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 297 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 298 | static void notrace persistent_ram_update(struct persistent_ram_zone *prz, |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 299 | const void *s, unsigned int start, unsigned int count) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 300 | { |
| 301 | struct persistent_ram_buffer *buffer = prz->buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 302 | memcpy(buffer->data + start, s, count); |
| 303 | persistent_ram_update_ecc(prz, start, count); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 304 | } |
| 305 | |
Anton Vorontsov | 201e4ac | 2012-05-26 06:07:49 -0700 | [diff] [blame] | 306 | void persistent_ram_save_old(struct persistent_ram_zone *prz) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 307 | { |
| 308 | struct persistent_ram_buffer *buffer = prz->buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 309 | size_t size = buffer_size(prz); |
| 310 | size_t start = buffer_start(prz); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 311 | |
Anton Vorontsov | 201e4ac | 2012-05-26 06:07:49 -0700 | [diff] [blame] | 312 | if (!size) |
| 313 | return; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 314 | |
Anton Vorontsov | 201e4ac | 2012-05-26 06:07:49 -0700 | [diff] [blame] | 315 | if (!prz->old_log) { |
| 316 | persistent_ram_ecc_old(prz); |
| 317 | prz->old_log = kmalloc(size, GFP_KERNEL); |
| 318 | } |
| 319 | if (!prz->old_log) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 320 | pr_err("failed to allocate buffer\n"); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 321 | return; |
| 322 | } |
| 323 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 324 | prz->old_log_size = size; |
| 325 | memcpy(prz->old_log, &buffer->data[start], size - start); |
| 326 | memcpy(prz->old_log + size - start, &buffer->data[0], start); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 327 | } |
| 328 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 329 | int notrace persistent_ram_write(struct persistent_ram_zone *prz, |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 330 | const void *s, unsigned int count) |
| 331 | { |
| 332 | int rem; |
| 333 | int c = count; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 334 | size_t start; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 335 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 336 | if (unlikely(c > prz->buffer_size)) { |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 337 | s += c - prz->buffer_size; |
| 338 | c = prz->buffer_size; |
| 339 | } |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 340 | |
Anton Vorontsov | 484dd30 | 2012-05-11 17:17:17 -0700 | [diff] [blame] | 341 | buffer_size_add(prz, c); |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 342 | |
| 343 | start = buffer_start_add(prz, c); |
| 344 | |
| 345 | rem = prz->buffer_size - start; |
| 346 | if (unlikely(rem < c)) { |
| 347 | persistent_ram_update(prz, s, start, rem); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 348 | s += rem; |
| 349 | c -= rem; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 350 | start = 0; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 351 | } |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 352 | persistent_ram_update(prz, s, start, c); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 353 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 354 | persistent_ram_update_header_ecc(prz); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 355 | |
| 356 | return count; |
| 357 | } |
| 358 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 359 | size_t persistent_ram_old_size(struct persistent_ram_zone *prz) |
| 360 | { |
| 361 | return prz->old_log_size; |
| 362 | } |
| 363 | |
| 364 | void *persistent_ram_old(struct persistent_ram_zone *prz) |
| 365 | { |
| 366 | return prz->old_log; |
| 367 | } |
| 368 | |
| 369 | void persistent_ram_free_old(struct persistent_ram_zone *prz) |
| 370 | { |
| 371 | kfree(prz->old_log); |
| 372 | prz->old_log = NULL; |
| 373 | prz->old_log_size = 0; |
| 374 | } |
| 375 | |
Anton Vorontsov | fce3979 | 2012-05-26 06:07:51 -0700 | [diff] [blame] | 376 | void persistent_ram_zap(struct persistent_ram_zone *prz) |
| 377 | { |
| 378 | atomic_set(&prz->buffer->start, 0); |
| 379 | atomic_set(&prz->buffer->size, 0); |
| 380 | persistent_ram_update_header_ecc(prz); |
| 381 | } |
| 382 | |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 383 | static void *persistent_ram_vmap(phys_addr_t start, size_t size) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 384 | { |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 385 | struct page **pages; |
| 386 | phys_addr_t page_start; |
| 387 | unsigned int page_count; |
| 388 | pgprot_t prot; |
| 389 | unsigned int i; |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 390 | void *vaddr; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 391 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 392 | page_start = start - offset_in_page(start); |
| 393 | page_count = DIV_ROUND_UP(size + offset_in_page(start), PAGE_SIZE); |
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 | prot = pgprot_noncached(PAGE_KERNEL); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 396 | |
Fabian Frederick | b8f52d8 | 2014-08-08 14:22:35 -0700 | [diff] [blame] | 397 | pages = kmalloc_array(page_count, sizeof(struct page *), GFP_KERNEL); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 398 | if (!pages) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 399 | pr_err("%s: Failed to allocate array for %u pages\n", |
| 400 | __func__, page_count); |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 401 | return NULL; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 402 | } |
| 403 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 404 | for (i = 0; i < page_count; i++) { |
| 405 | phys_addr_t addr = page_start + i * PAGE_SIZE; |
| 406 | pages[i] = pfn_to_page(addr >> PAGE_SHIFT); |
| 407 | } |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 408 | vaddr = vmap(pages, page_count, VM_MAP, prot); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 409 | kfree(pages); |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 410 | |
| 411 | return vaddr; |
| 412 | } |
| 413 | |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 414 | static void *persistent_ram_iomap(phys_addr_t start, size_t size) |
| 415 | { |
| 416 | if (!request_mem_region(start, size, "persistent_ram")) { |
| 417 | pr_err("request mem region (0x%llx@0x%llx) failed\n", |
| 418 | (unsigned long long)size, (unsigned long long)start); |
| 419 | return NULL; |
| 420 | } |
| 421 | |
Rob Herring | 0405a5c | 2013-04-08 20:23:33 -0500 | [diff] [blame] | 422 | buffer_start_add = buffer_start_add_locked; |
| 423 | buffer_size_add = buffer_size_add_locked; |
| 424 | |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 425 | return ioremap(start, size); |
| 426 | } |
| 427 | |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 428 | static int persistent_ram_buffer_map(phys_addr_t start, phys_addr_t size, |
| 429 | struct persistent_ram_zone *prz) |
| 430 | { |
Anton Vorontsov | d3b4876 | 2012-05-11 17:18:05 -0700 | [diff] [blame] | 431 | prz->paddr = start; |
| 432 | prz->size = size; |
| 433 | |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 434 | if (pfn_valid(start >> PAGE_SHIFT)) |
| 435 | prz->vaddr = persistent_ram_vmap(start, size); |
| 436 | else |
| 437 | prz->vaddr = persistent_ram_iomap(start, size); |
| 438 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 439 | if (!prz->vaddr) { |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 440 | pr_err("%s: Failed to map 0x%llx pages at 0x%llx\n", __func__, |
| 441 | (unsigned long long)size, (unsigned long long)start); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 442 | return -ENOMEM; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 443 | } |
| 444 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 445 | prz->buffer = prz->vaddr + offset_in_page(start); |
| 446 | prz->buffer_size = size - sizeof(struct persistent_ram_buffer); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 447 | |
| 448 | return 0; |
| 449 | } |
| 450 | |
Greg Kroah-Hartman | f568f6c | 2012-12-21 15:02:05 -0800 | [diff] [blame] | 451 | static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig, |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 452 | struct persistent_ram_ecc_info *ecc_info) |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 453 | { |
Anton Vorontsov | bb4206f | 2012-05-11 17:17:25 -0700 | [diff] [blame] | 454 | int ret; |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 455 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 456 | ret = persistent_ram_init_ecc(prz, ecc_info); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 457 | if (ret) |
Anton Vorontsov | bb4206f | 2012-05-11 17:17:25 -0700 | [diff] [blame] | 458 | return ret; |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 459 | |
Anton Vorontsov | cbe7cbf | 2012-07-17 12:11:12 -0700 | [diff] [blame] | 460 | sig ^= PERSISTENT_RAM_SIG; |
| 461 | |
| 462 | if (prz->buffer->sig == sig) { |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 463 | if (buffer_size(prz) > prz->buffer_size || |
| 464 | buffer_start(prz) > buffer_size(prz)) |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 465 | pr_info("found existing invalid buffer, size %zu, start %zu\n", |
| 466 | buffer_size(prz), buffer_start(prz)); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 467 | else { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 468 | pr_debug("found existing buffer, size %zu, start %zu\n", |
| 469 | buffer_size(prz), buffer_start(prz)); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 470 | persistent_ram_save_old(prz); |
Anton Vorontsov | 25b63da | 2012-05-26 06:07:50 -0700 | [diff] [blame] | 471 | return 0; |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 472 | } |
| 473 | } else { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 474 | pr_debug("no valid data in buffer (sig = 0x%08x)\n", |
| 475 | prz->buffer->sig); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 476 | } |
| 477 | |
Anton Vorontsov | cbe7cbf | 2012-07-17 12:11:12 -0700 | [diff] [blame] | 478 | prz->buffer->sig = sig; |
Anton Vorontsov | fce3979 | 2012-05-26 06:07:51 -0700 | [diff] [blame] | 479 | persistent_ram_zap(prz); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 480 | |
Anton Vorontsov | bb4206f | 2012-05-11 17:17:25 -0700 | [diff] [blame] | 481 | return 0; |
| 482 | } |
| 483 | |
Anton Vorontsov | d3b4876 | 2012-05-11 17:18:05 -0700 | [diff] [blame] | 484 | void persistent_ram_free(struct persistent_ram_zone *prz) |
| 485 | { |
Anton Vorontsov | beeb943 | 2012-06-18 19:15:52 -0700 | [diff] [blame] | 486 | if (!prz) |
| 487 | return; |
| 488 | |
| 489 | if (prz->vaddr) { |
| 490 | if (pfn_valid(prz->paddr >> PAGE_SHIFT)) { |
| 491 | vunmap(prz->vaddr); |
| 492 | } else { |
| 493 | iounmap(prz->vaddr); |
| 494 | release_mem_region(prz->paddr, prz->size); |
| 495 | } |
| 496 | prz->vaddr = NULL; |
Anton Vorontsov | d3b4876 | 2012-05-11 17:18:05 -0700 | [diff] [blame] | 497 | } |
| 498 | persistent_ram_free_old(prz); |
| 499 | kfree(prz); |
| 500 | } |
| 501 | |
Greg Kroah-Hartman | f568f6c | 2012-12-21 15:02:05 -0800 | [diff] [blame] | 502 | struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size, |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 503 | u32 sig, struct persistent_ram_ecc_info *ecc_info) |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 504 | { |
| 505 | struct persistent_ram_zone *prz; |
| 506 | int ret = -ENOMEM; |
| 507 | |
| 508 | prz = kzalloc(sizeof(struct persistent_ram_zone), GFP_KERNEL); |
| 509 | if (!prz) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 510 | pr_err("failed to allocate persistent ram zone\n"); |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 511 | goto err; |
| 512 | } |
| 513 | |
| 514 | ret = persistent_ram_buffer_map(start, size, prz); |
| 515 | if (ret) |
| 516 | goto err; |
| 517 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 518 | ret = persistent_ram_post_init(prz, sig, ecc_info); |
Anton Vorontsov | beeb943 | 2012-06-18 19:15:52 -0700 | [diff] [blame] | 519 | if (ret) |
| 520 | goto err; |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 521 | |
| 522 | return prz; |
| 523 | err: |
Anton Vorontsov | beeb943 | 2012-06-18 19:15:52 -0700 | [diff] [blame] | 524 | persistent_ram_free(prz); |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 525 | return ERR_PTR(ret); |
| 526 | } |