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 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 15 | #include <linux/device.h> |
| 16 | #include <linux/err.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 17 | #include <linux/errno.h> |
| 18 | #include <linux/kernel.h> |
| 19 | #include <linux/init.h> |
| 20 | #include <linux/io.h> |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 21 | #include <linux/list.h> |
| 22 | #include <linux/memblock.h> |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 23 | #include <linux/rslib.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 24 | #include <linux/slab.h> |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 25 | #include <linux/vmalloc.h> |
Anton Vorontsov | cddb875 | 2012-05-17 00:15:08 -0700 | [diff] [blame] | 26 | #include <linux/pstore_ram.h> |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 27 | #include <asm/page.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 28 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 29 | struct persistent_ram_buffer { |
| 30 | uint32_t sig; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 31 | atomic_t start; |
| 32 | atomic_t size; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 33 | uint8_t data[0]; |
| 34 | }; |
| 35 | |
| 36 | #define PERSISTENT_RAM_SIG (0x43474244) /* DBGC */ |
| 37 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 38 | static inline size_t buffer_size(struct persistent_ram_zone *prz) |
| 39 | { |
| 40 | return atomic_read(&prz->buffer->size); |
| 41 | } |
| 42 | |
| 43 | static inline size_t buffer_start(struct persistent_ram_zone *prz) |
| 44 | { |
| 45 | return atomic_read(&prz->buffer->start); |
| 46 | } |
| 47 | |
| 48 | /* increase and wrap the start pointer, returning the old value */ |
| 49 | static inline size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a) |
| 50 | { |
| 51 | int old; |
| 52 | int new; |
| 53 | |
| 54 | do { |
| 55 | old = atomic_read(&prz->buffer->start); |
| 56 | new = old + a; |
| 57 | while (unlikely(new > prz->buffer_size)) |
| 58 | new -= prz->buffer_size; |
| 59 | } while (atomic_cmpxchg(&prz->buffer->start, old, new) != old); |
| 60 | |
| 61 | return old; |
| 62 | } |
| 63 | |
| 64 | /* increase the size counter until it hits the max size */ |
| 65 | static inline void buffer_size_add(struct persistent_ram_zone *prz, size_t a) |
| 66 | { |
| 67 | size_t old; |
| 68 | size_t new; |
| 69 | |
| 70 | if (atomic_read(&prz->buffer->size) == prz->buffer_size) |
| 71 | return; |
| 72 | |
| 73 | do { |
| 74 | old = atomic_read(&prz->buffer->size); |
| 75 | new = old + a; |
| 76 | if (new > prz->buffer_size) |
| 77 | new = prz->buffer_size; |
| 78 | } while (atomic_cmpxchg(&prz->buffer->size, old, new) != old); |
| 79 | } |
| 80 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 81 | static void notrace persistent_ram_encode_rs8(struct persistent_ram_zone *prz, |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 82 | uint8_t *data, size_t len, uint8_t *ecc) |
| 83 | { |
| 84 | int i; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 85 | uint16_t par[prz->ecc_info.ecc_size]; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 86 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 87 | /* Initialize the parity buffer */ |
| 88 | memset(par, 0, sizeof(par)); |
| 89 | encode_rs8(prz->rs_decoder, data, len, par, 0); |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 90 | for (i = 0; i < prz->ecc_info.ecc_size; i++) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 91 | ecc[i] = par[i]; |
| 92 | } |
| 93 | |
| 94 | static int persistent_ram_decode_rs8(struct persistent_ram_zone *prz, |
| 95 | void *data, size_t len, uint8_t *ecc) |
| 96 | { |
| 97 | int i; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 98 | uint16_t par[prz->ecc_info.ecc_size]; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 99 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 100 | for (i = 0; i < prz->ecc_info.ecc_size; i++) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 101 | par[i] = ecc[i]; |
| 102 | return decode_rs8(prz->rs_decoder, data, par, len, |
| 103 | NULL, 0, NULL, 0, NULL); |
| 104 | } |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 105 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 106 | static void notrace persistent_ram_update_ecc(struct persistent_ram_zone *prz, |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 107 | unsigned int start, unsigned int count) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 108 | { |
| 109 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 110 | uint8_t *buffer_end = buffer->data + prz->buffer_size; |
| 111 | uint8_t *block; |
| 112 | uint8_t *par; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 113 | int ecc_block_size = prz->ecc_info.block_size; |
| 114 | int ecc_size = prz->ecc_info.ecc_size; |
| 115 | int size = ecc_block_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 116 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 117 | if (!ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 118 | return; |
| 119 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 120 | block = buffer->data + (start & ~(ecc_block_size - 1)); |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 121 | par = prz->par_buffer + (start / ecc_block_size) * ecc_size; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 122 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 123 | do { |
| 124 | if (block + ecc_block_size > buffer_end) |
| 125 | size = buffer_end - block; |
| 126 | persistent_ram_encode_rs8(prz, block, size, par); |
| 127 | block += ecc_block_size; |
| 128 | par += ecc_size; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 129 | } while (block < buffer->data + start + count); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 130 | } |
| 131 | |
| 132 | static void persistent_ram_update_header_ecc(struct persistent_ram_zone *prz) |
| 133 | { |
| 134 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 135 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 136 | if (!prz->ecc_info.ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 137 | return; |
| 138 | |
| 139 | persistent_ram_encode_rs8(prz, (uint8_t *)buffer, sizeof(*buffer), |
| 140 | prz->par_header); |
| 141 | } |
| 142 | |
| 143 | static void persistent_ram_ecc_old(struct persistent_ram_zone *prz) |
| 144 | { |
| 145 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 146 | uint8_t *block; |
| 147 | uint8_t *par; |
| 148 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 149 | if (!prz->ecc_info.ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 150 | return; |
| 151 | |
| 152 | block = buffer->data; |
| 153 | par = prz->par_buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 154 | while (block < buffer->data + buffer_size(prz)) { |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 155 | int numerr; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 156 | int size = prz->ecc_info.block_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 157 | if (block + size > buffer->data + prz->buffer_size) |
| 158 | size = buffer->data + prz->buffer_size - block; |
| 159 | numerr = persistent_ram_decode_rs8(prz, block, size, par); |
| 160 | if (numerr > 0) { |
| 161 | pr_devel("persistent_ram: error in block %p, %d\n", |
| 162 | block, numerr); |
| 163 | prz->corrected_bytes += numerr; |
| 164 | } else if (numerr < 0) { |
| 165 | pr_devel("persistent_ram: uncorrectable error in block %p\n", |
| 166 | block); |
| 167 | prz->bad_blocks++; |
| 168 | } |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 169 | block += prz->ecc_info.block_size; |
| 170 | par += prz->ecc_info.ecc_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 171 | } |
| 172 | } |
| 173 | |
Anton Vorontsov | 5ca5d4e | 2012-07-09 17:03:19 -0700 | [diff] [blame] | 174 | static int persistent_ram_init_ecc(struct persistent_ram_zone *prz, |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 175 | struct persistent_ram_ecc_info *ecc_info) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 176 | { |
| 177 | int numerr; |
| 178 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 179 | int ecc_blocks; |
Anton Vorontsov | 1e6a9e5 | 2012-06-18 19:15:53 -0700 | [diff] [blame] | 180 | size_t ecc_total; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 181 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 182 | if (!ecc_info || !ecc_info->ecc_size) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 183 | return 0; |
| 184 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 185 | prz->ecc_info.block_size = ecc_info->block_size ?: 128; |
| 186 | prz->ecc_info.ecc_size = ecc_info->ecc_size ?: 16; |
| 187 | prz->ecc_info.symsize = ecc_info->symsize ?: 8; |
| 188 | prz->ecc_info.poly = ecc_info->poly ?: 0x11d; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 189 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 190 | ecc_blocks = DIV_ROUND_UP(prz->buffer_size - prz->ecc_info.ecc_size, |
| 191 | prz->ecc_info.block_size + |
| 192 | prz->ecc_info.ecc_size); |
| 193 | ecc_total = (ecc_blocks + 1) * prz->ecc_info.ecc_size; |
Anton Vorontsov | 1e6a9e5 | 2012-06-18 19:15:53 -0700 | [diff] [blame] | 194 | if (ecc_total >= prz->buffer_size) { |
| 195 | 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] | 196 | __func__, prz->ecc_info.ecc_size, |
| 197 | ecc_total, prz->buffer_size); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 198 | return -EINVAL; |
| 199 | } |
| 200 | |
Anton Vorontsov | 1e6a9e5 | 2012-06-18 19:15:53 -0700 | [diff] [blame] | 201 | prz->buffer_size -= ecc_total; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 202 | prz->par_buffer = buffer->data + prz->buffer_size; |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 203 | prz->par_header = prz->par_buffer + |
| 204 | ecc_blocks * prz->ecc_info.ecc_size; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 205 | |
| 206 | /* |
| 207 | * first consecutive root is 0 |
| 208 | * primitive element to generate roots = 1 |
| 209 | */ |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 210 | prz->rs_decoder = init_rs(prz->ecc_info.symsize, prz->ecc_info.poly, |
| 211 | 0, 1, prz->ecc_info.ecc_size); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 212 | if (prz->rs_decoder == NULL) { |
| 213 | pr_info("persistent_ram: init_rs failed\n"); |
| 214 | return -EINVAL; |
| 215 | } |
| 216 | |
| 217 | prz->corrected_bytes = 0; |
| 218 | prz->bad_blocks = 0; |
| 219 | |
| 220 | numerr = persistent_ram_decode_rs8(prz, buffer, sizeof(*buffer), |
| 221 | prz->par_header); |
| 222 | if (numerr > 0) { |
| 223 | pr_info("persistent_ram: error in header, %d\n", numerr); |
| 224 | prz->corrected_bytes += numerr; |
| 225 | } else if (numerr < 0) { |
| 226 | pr_info("persistent_ram: uncorrectable error in header\n"); |
| 227 | prz->bad_blocks++; |
| 228 | } |
| 229 | |
| 230 | return 0; |
| 231 | } |
| 232 | |
| 233 | ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz, |
| 234 | char *str, size_t len) |
| 235 | { |
| 236 | ssize_t ret; |
| 237 | |
Arve Hjønnevåg | bd08ec3 | 2012-12-05 21:19:51 -0800 | [diff] [blame^] | 238 | if (!prz->ecc_info.ecc_size) |
| 239 | return 0; |
| 240 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 241 | if (prz->corrected_bytes || prz->bad_blocks) |
| 242 | ret = snprintf(str, len, "" |
| 243 | "\n%d Corrected bytes, %d unrecoverable blocks\n", |
| 244 | prz->corrected_bytes, prz->bad_blocks); |
| 245 | else |
| 246 | ret = snprintf(str, len, "\nNo errors detected\n"); |
| 247 | |
| 248 | return ret; |
| 249 | } |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 250 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 251 | static void notrace persistent_ram_update(struct persistent_ram_zone *prz, |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 252 | const void *s, unsigned int start, unsigned int count) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 253 | { |
| 254 | struct persistent_ram_buffer *buffer = prz->buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 255 | memcpy(buffer->data + start, s, count); |
| 256 | persistent_ram_update_ecc(prz, start, count); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 257 | } |
| 258 | |
Anton Vorontsov | 201e4ac | 2012-05-26 06:07:49 -0700 | [diff] [blame] | 259 | void persistent_ram_save_old(struct persistent_ram_zone *prz) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 260 | { |
| 261 | struct persistent_ram_buffer *buffer = prz->buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 262 | size_t size = buffer_size(prz); |
| 263 | size_t start = buffer_start(prz); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 264 | |
Anton Vorontsov | 201e4ac | 2012-05-26 06:07:49 -0700 | [diff] [blame] | 265 | if (!size) |
| 266 | return; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 267 | |
Anton Vorontsov | 201e4ac | 2012-05-26 06:07:49 -0700 | [diff] [blame] | 268 | if (!prz->old_log) { |
| 269 | persistent_ram_ecc_old(prz); |
| 270 | prz->old_log = kmalloc(size, GFP_KERNEL); |
| 271 | } |
| 272 | if (!prz->old_log) { |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 273 | pr_err("persistent_ram: failed to allocate buffer\n"); |
| 274 | return; |
| 275 | } |
| 276 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 277 | prz->old_log_size = size; |
| 278 | memcpy(prz->old_log, &buffer->data[start], size - start); |
| 279 | memcpy(prz->old_log + size - start, &buffer->data[0], start); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 280 | } |
| 281 | |
Colin Cross | a15d0b3 | 2012-03-07 17:34:36 -0800 | [diff] [blame] | 282 | int notrace persistent_ram_write(struct persistent_ram_zone *prz, |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 283 | const void *s, unsigned int count) |
| 284 | { |
| 285 | int rem; |
| 286 | int c = count; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 287 | size_t start; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 288 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 289 | if (unlikely(c > prz->buffer_size)) { |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 290 | s += c - prz->buffer_size; |
| 291 | c = prz->buffer_size; |
| 292 | } |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 293 | |
Anton Vorontsov | 484dd30 | 2012-05-11 17:17:17 -0700 | [diff] [blame] | 294 | buffer_size_add(prz, c); |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 295 | |
| 296 | start = buffer_start_add(prz, c); |
| 297 | |
| 298 | rem = prz->buffer_size - start; |
| 299 | if (unlikely(rem < c)) { |
| 300 | persistent_ram_update(prz, s, start, rem); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 301 | s += rem; |
| 302 | c -= rem; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 303 | start = 0; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 304 | } |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 305 | persistent_ram_update(prz, s, start, c); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 306 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 307 | persistent_ram_update_header_ecc(prz); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 308 | |
| 309 | return count; |
| 310 | } |
| 311 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 312 | size_t persistent_ram_old_size(struct persistent_ram_zone *prz) |
| 313 | { |
| 314 | return prz->old_log_size; |
| 315 | } |
| 316 | |
| 317 | void *persistent_ram_old(struct persistent_ram_zone *prz) |
| 318 | { |
| 319 | return prz->old_log; |
| 320 | } |
| 321 | |
| 322 | void persistent_ram_free_old(struct persistent_ram_zone *prz) |
| 323 | { |
| 324 | kfree(prz->old_log); |
| 325 | prz->old_log = NULL; |
| 326 | prz->old_log_size = 0; |
| 327 | } |
| 328 | |
Anton Vorontsov | fce3979 | 2012-05-26 06:07:51 -0700 | [diff] [blame] | 329 | void persistent_ram_zap(struct persistent_ram_zone *prz) |
| 330 | { |
| 331 | atomic_set(&prz->buffer->start, 0); |
| 332 | atomic_set(&prz->buffer->size, 0); |
| 333 | persistent_ram_update_header_ecc(prz); |
| 334 | } |
| 335 | |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 336 | static void *persistent_ram_vmap(phys_addr_t start, size_t size) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 337 | { |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 338 | struct page **pages; |
| 339 | phys_addr_t page_start; |
| 340 | unsigned int page_count; |
| 341 | pgprot_t prot; |
| 342 | unsigned int i; |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 343 | void *vaddr; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 344 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 345 | page_start = start - offset_in_page(start); |
| 346 | page_count = DIV_ROUND_UP(size + offset_in_page(start), PAGE_SIZE); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 347 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 348 | prot = pgprot_noncached(PAGE_KERNEL); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 349 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 350 | pages = kmalloc(sizeof(struct page *) * page_count, GFP_KERNEL); |
| 351 | if (!pages) { |
| 352 | pr_err("%s: Failed to allocate array for %u pages\n", __func__, |
| 353 | page_count); |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 354 | return NULL; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 355 | } |
| 356 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 357 | for (i = 0; i < page_count; i++) { |
| 358 | phys_addr_t addr = page_start + i * PAGE_SIZE; |
| 359 | pages[i] = pfn_to_page(addr >> PAGE_SHIFT); |
| 360 | } |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 361 | vaddr = vmap(pages, page_count, VM_MAP, prot); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 362 | kfree(pages); |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 363 | |
| 364 | return vaddr; |
| 365 | } |
| 366 | |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 367 | static void *persistent_ram_iomap(phys_addr_t start, size_t size) |
| 368 | { |
| 369 | if (!request_mem_region(start, size, "persistent_ram")) { |
| 370 | pr_err("request mem region (0x%llx@0x%llx) failed\n", |
| 371 | (unsigned long long)size, (unsigned long long)start); |
| 372 | return NULL; |
| 373 | } |
| 374 | |
| 375 | return ioremap(start, size); |
| 376 | } |
| 377 | |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 378 | static int persistent_ram_buffer_map(phys_addr_t start, phys_addr_t size, |
| 379 | struct persistent_ram_zone *prz) |
| 380 | { |
Anton Vorontsov | d3b4876 | 2012-05-11 17:18:05 -0700 | [diff] [blame] | 381 | prz->paddr = start; |
| 382 | prz->size = size; |
| 383 | |
Anton Vorontsov | 24c3d2f | 2012-05-11 17:17:54 -0700 | [diff] [blame] | 384 | if (pfn_valid(start >> PAGE_SHIFT)) |
| 385 | prz->vaddr = persistent_ram_vmap(start, size); |
| 386 | else |
| 387 | prz->vaddr = persistent_ram_iomap(start, size); |
| 388 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 389 | if (!prz->vaddr) { |
Anton Vorontsov | 2b1321e | 2012-05-11 17:17:43 -0700 | [diff] [blame] | 390 | pr_err("%s: Failed to map 0x%llx pages at 0x%llx\n", __func__, |
| 391 | (unsigned long long)size, (unsigned long long)start); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 392 | return -ENOMEM; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 393 | } |
| 394 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 395 | prz->buffer = prz->vaddr + offset_in_page(start); |
| 396 | prz->buffer_size = size - sizeof(struct persistent_ram_buffer); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 397 | |
| 398 | return 0; |
| 399 | } |
| 400 | |
Greg Kroah-Hartman | f568f6c | 2012-12-21 15:02:05 -0800 | [diff] [blame] | 401 | 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] | 402 | struct persistent_ram_ecc_info *ecc_info) |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 403 | { |
Anton Vorontsov | bb4206f | 2012-05-11 17:17:25 -0700 | [diff] [blame] | 404 | int ret; |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 405 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 406 | ret = persistent_ram_init_ecc(prz, ecc_info); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 407 | if (ret) |
Anton Vorontsov | bb4206f | 2012-05-11 17:17:25 -0700 | [diff] [blame] | 408 | return ret; |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 409 | |
Anton Vorontsov | cbe7cbf | 2012-07-17 12:11:12 -0700 | [diff] [blame] | 410 | sig ^= PERSISTENT_RAM_SIG; |
| 411 | |
| 412 | if (prz->buffer->sig == sig) { |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 413 | if (buffer_size(prz) > prz->buffer_size || |
| 414 | buffer_start(prz) > buffer_size(prz)) |
| 415 | pr_info("persistent_ram: found existing invalid buffer," |
Randy Dunlap | f56d711 | 2012-03-30 10:31:32 -0700 | [diff] [blame] | 416 | " size %zu, start %zu\n", |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 417 | buffer_size(prz), buffer_start(prz)); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 418 | else { |
Anton Vorontsov | 602b5be | 2012-05-26 06:20:24 -0700 | [diff] [blame] | 419 | pr_debug("persistent_ram: found existing buffer," |
Randy Dunlap | f56d711 | 2012-03-30 10:31:32 -0700 | [diff] [blame] | 420 | " size %zu, start %zu\n", |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 421 | buffer_size(prz), buffer_start(prz)); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 422 | persistent_ram_save_old(prz); |
Anton Vorontsov | 25b63da | 2012-05-26 06:07:50 -0700 | [diff] [blame] | 423 | return 0; |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 424 | } |
| 425 | } else { |
Anton Vorontsov | 602b5be | 2012-05-26 06:20:24 -0700 | [diff] [blame] | 426 | pr_debug("persistent_ram: no valid data in buffer" |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame] | 427 | " (sig = 0x%08x)\n", prz->buffer->sig); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 428 | } |
| 429 | |
Anton Vorontsov | cbe7cbf | 2012-07-17 12:11:12 -0700 | [diff] [blame] | 430 | prz->buffer->sig = sig; |
Anton Vorontsov | fce3979 | 2012-05-26 06:07:51 -0700 | [diff] [blame] | 431 | persistent_ram_zap(prz); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 432 | |
Anton Vorontsov | bb4206f | 2012-05-11 17:17:25 -0700 | [diff] [blame] | 433 | return 0; |
| 434 | } |
| 435 | |
Anton Vorontsov | d3b4876 | 2012-05-11 17:18:05 -0700 | [diff] [blame] | 436 | void persistent_ram_free(struct persistent_ram_zone *prz) |
| 437 | { |
Anton Vorontsov | beeb943 | 2012-06-18 19:15:52 -0700 | [diff] [blame] | 438 | if (!prz) |
| 439 | return; |
| 440 | |
| 441 | if (prz->vaddr) { |
| 442 | if (pfn_valid(prz->paddr >> PAGE_SHIFT)) { |
| 443 | vunmap(prz->vaddr); |
| 444 | } else { |
| 445 | iounmap(prz->vaddr); |
| 446 | release_mem_region(prz->paddr, prz->size); |
| 447 | } |
| 448 | prz->vaddr = NULL; |
Anton Vorontsov | d3b4876 | 2012-05-11 17:18:05 -0700 | [diff] [blame] | 449 | } |
| 450 | persistent_ram_free_old(prz); |
| 451 | kfree(prz); |
| 452 | } |
| 453 | |
Greg Kroah-Hartman | f568f6c | 2012-12-21 15:02:05 -0800 | [diff] [blame] | 454 | 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] | 455 | u32 sig, struct persistent_ram_ecc_info *ecc_info) |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 456 | { |
| 457 | struct persistent_ram_zone *prz; |
| 458 | int ret = -ENOMEM; |
| 459 | |
| 460 | prz = kzalloc(sizeof(struct persistent_ram_zone), GFP_KERNEL); |
| 461 | if (!prz) { |
| 462 | pr_err("persistent_ram: failed to allocate persistent ram zone\n"); |
| 463 | goto err; |
| 464 | } |
| 465 | |
| 466 | ret = persistent_ram_buffer_map(start, size, prz); |
| 467 | if (ret) |
| 468 | goto err; |
| 469 | |
Arve Hjønnevåg | c31ad08 | 2012-05-22 16:33:23 -0700 | [diff] [blame] | 470 | ret = persistent_ram_post_init(prz, sig, ecc_info); |
Anton Vorontsov | beeb943 | 2012-06-18 19:15:52 -0700 | [diff] [blame] | 471 | if (ret) |
| 472 | goto err; |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 473 | |
| 474 | return prz; |
| 475 | err: |
Anton Vorontsov | beeb943 | 2012-06-18 19:15:52 -0700 | [diff] [blame] | 476 | persistent_ram_free(prz); |
Anton Vorontsov | 8cf5aff | 2012-05-11 17:17:34 -0700 | [diff] [blame] | 477 | return ERR_PTR(ret); |
| 478 | } |