Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Swap block device support for MTDs |
| 3 | * Turns an MTD device into a swap device with block wear leveling |
| 4 | * |
| 5 | * Copyright © 2007,2011 Nokia Corporation. All rights reserved. |
| 6 | * |
| 7 | * Authors: Jarkko Lavinen <jarkko.lavinen@nokia.com> |
| 8 | * |
| 9 | * Based on Richard Purdie's earlier implementation in 2007. Background |
| 10 | * support and lock-less operation written by Adrian Hunter. |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or |
| 13 | * modify it under the terms of the GNU General Public License |
| 14 | * version 2 as published by the Free Software Foundation. |
| 15 | * |
| 16 | * This program is distributed in the hope that it will be useful, but |
| 17 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 19 | * General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU General Public License |
| 22 | * along with this program; if not, write to the Free Software |
| 23 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA |
| 24 | * 02110-1301 USA |
| 25 | */ |
| 26 | |
| 27 | #include <linux/kernel.h> |
| 28 | #include <linux/module.h> |
| 29 | #include <linux/mtd/mtd.h> |
| 30 | #include <linux/mtd/blktrans.h> |
| 31 | #include <linux/rbtree.h> |
| 32 | #include <linux/sched.h> |
| 33 | #include <linux/slab.h> |
| 34 | #include <linux/vmalloc.h> |
| 35 | #include <linux/genhd.h> |
| 36 | #include <linux/swap.h> |
| 37 | #include <linux/debugfs.h> |
| 38 | #include <linux/seq_file.h> |
| 39 | #include <linux/device.h> |
| 40 | #include <linux/math64.h> |
| 41 | |
| 42 | #define MTDSWAP_PREFIX "mtdswap" |
| 43 | |
| 44 | /* |
| 45 | * The number of free eraseblocks when GC should stop |
| 46 | */ |
| 47 | #define CLEAN_BLOCK_THRESHOLD 20 |
| 48 | |
| 49 | /* |
| 50 | * Number of free eraseblocks below which GC can also collect low frag |
| 51 | * blocks. |
| 52 | */ |
| 53 | #define LOW_FRAG_GC_TRESHOLD 5 |
| 54 | |
| 55 | /* |
| 56 | * Wear level cost amortization. We want to do wear leveling on the background |
| 57 | * without disturbing gc too much. This is made by defining max GC frequency. |
| 58 | * Frequency value 6 means 1/6 of the GC passes will pick an erase block based |
| 59 | * on the biggest wear difference rather than the biggest dirtiness. |
| 60 | * |
| 61 | * The lower freq2 should be chosen so that it makes sure the maximum erase |
| 62 | * difference will decrease even if a malicious application is deliberately |
| 63 | * trying to make erase differences large. |
| 64 | */ |
| 65 | #define MAX_ERASE_DIFF 4000 |
| 66 | #define COLLECT_NONDIRTY_BASE MAX_ERASE_DIFF |
| 67 | #define COLLECT_NONDIRTY_FREQ1 6 |
| 68 | #define COLLECT_NONDIRTY_FREQ2 4 |
| 69 | |
| 70 | #define PAGE_UNDEF UINT_MAX |
| 71 | #define BLOCK_UNDEF UINT_MAX |
| 72 | #define BLOCK_ERROR (UINT_MAX - 1) |
| 73 | #define BLOCK_MAX (UINT_MAX - 2) |
| 74 | |
| 75 | #define EBLOCK_BAD (1 << 0) |
| 76 | #define EBLOCK_NOMAGIC (1 << 1) |
| 77 | #define EBLOCK_BITFLIP (1 << 2) |
| 78 | #define EBLOCK_FAILED (1 << 3) |
| 79 | #define EBLOCK_READERR (1 << 4) |
| 80 | #define EBLOCK_IDX_SHIFT 5 |
| 81 | |
| 82 | struct swap_eb { |
| 83 | struct rb_node rb; |
| 84 | struct rb_root *root; |
| 85 | |
| 86 | unsigned int flags; |
| 87 | unsigned int active_count; |
| 88 | unsigned int erase_count; |
Brian Norris | 92394b5c | 2011-07-20 09:53:42 -0700 | [diff] [blame] | 89 | unsigned int pad; /* speeds up pointer decrement */ |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 90 | }; |
| 91 | |
| 92 | #define MTDSWAP_ECNT_MIN(rbroot) (rb_entry(rb_first(rbroot), struct swap_eb, \ |
| 93 | rb)->erase_count) |
| 94 | #define MTDSWAP_ECNT_MAX(rbroot) (rb_entry(rb_last(rbroot), struct swap_eb, \ |
| 95 | rb)->erase_count) |
| 96 | |
| 97 | struct mtdswap_tree { |
| 98 | struct rb_root root; |
| 99 | unsigned int count; |
| 100 | }; |
| 101 | |
| 102 | enum { |
| 103 | MTDSWAP_CLEAN, |
| 104 | MTDSWAP_USED, |
| 105 | MTDSWAP_LOWFRAG, |
| 106 | MTDSWAP_HIFRAG, |
| 107 | MTDSWAP_DIRTY, |
| 108 | MTDSWAP_BITFLIP, |
| 109 | MTDSWAP_FAILING, |
| 110 | MTDSWAP_TREE_CNT, |
| 111 | }; |
| 112 | |
| 113 | struct mtdswap_dev { |
| 114 | struct mtd_blktrans_dev *mbd_dev; |
| 115 | struct mtd_info *mtd; |
| 116 | struct device *dev; |
| 117 | |
| 118 | unsigned int *page_data; |
| 119 | unsigned int *revmap; |
| 120 | |
| 121 | unsigned int eblks; |
| 122 | unsigned int spare_eblks; |
| 123 | unsigned int pages_per_eblk; |
| 124 | unsigned int max_erase_count; |
| 125 | struct swap_eb *eb_data; |
| 126 | |
| 127 | struct mtdswap_tree trees[MTDSWAP_TREE_CNT]; |
| 128 | |
| 129 | unsigned long long sect_read_count; |
| 130 | unsigned long long sect_write_count; |
| 131 | unsigned long long mtd_write_count; |
| 132 | unsigned long long mtd_read_count; |
| 133 | unsigned long long discard_count; |
| 134 | unsigned long long discard_page_count; |
| 135 | |
| 136 | unsigned int curr_write_pos; |
| 137 | struct swap_eb *curr_write; |
| 138 | |
| 139 | char *page_buf; |
| 140 | char *oob_buf; |
| 141 | |
| 142 | struct dentry *debugfs_root; |
| 143 | }; |
| 144 | |
| 145 | struct mtdswap_oobdata { |
| 146 | __le16 magic; |
| 147 | __le32 count; |
Brian Norris | 31f7546 | 2014-07-21 19:07:22 -0700 | [diff] [blame] | 148 | } __packed; |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 149 | |
| 150 | #define MTDSWAP_MAGIC_CLEAN 0x2095 |
| 151 | #define MTDSWAP_MAGIC_DIRTY (MTDSWAP_MAGIC_CLEAN + 1) |
| 152 | #define MTDSWAP_TYPE_CLEAN 0 |
| 153 | #define MTDSWAP_TYPE_DIRTY 1 |
| 154 | #define MTDSWAP_OOBSIZE sizeof(struct mtdswap_oobdata) |
| 155 | |
| 156 | #define MTDSWAP_ERASE_RETRIES 3 /* Before marking erase block bad */ |
| 157 | #define MTDSWAP_IO_RETRIES 3 |
| 158 | |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 159 | enum { |
| 160 | MTDSWAP_SCANNED_CLEAN, |
| 161 | MTDSWAP_SCANNED_DIRTY, |
| 162 | MTDSWAP_SCANNED_BITFLIP, |
| 163 | MTDSWAP_SCANNED_BAD, |
| 164 | }; |
| 165 | |
| 166 | /* |
| 167 | * In the worst case mtdswap_writesect() has allocated the last clean |
| 168 | * page from the current block and is then pre-empted by the GC |
| 169 | * thread. The thread can consume a full erase block when moving a |
| 170 | * block. |
| 171 | */ |
| 172 | #define MIN_SPARE_EBLOCKS 2 |
| 173 | #define MIN_ERASE_BLOCKS (MIN_SPARE_EBLOCKS + 1) |
| 174 | |
| 175 | #define TREE_ROOT(d, name) (&d->trees[MTDSWAP_ ## name].root) |
| 176 | #define TREE_EMPTY(d, name) (TREE_ROOT(d, name)->rb_node == NULL) |
| 177 | #define TREE_NONEMPTY(d, name) (!TREE_EMPTY(d, name)) |
| 178 | #define TREE_COUNT(d, name) (d->trees[MTDSWAP_ ## name].count) |
| 179 | |
| 180 | #define MTDSWAP_MBD_TO_MTDSWAP(dev) ((struct mtdswap_dev *)dev->priv) |
| 181 | |
| 182 | static char partitions[128] = ""; |
| 183 | module_param_string(partitions, partitions, sizeof(partitions), 0444); |
| 184 | MODULE_PARM_DESC(partitions, "MTD partition numbers to use as swap " |
| 185 | "partitions=\"1,3,5\""); |
| 186 | |
| 187 | static unsigned int spare_eblocks = 10; |
| 188 | module_param(spare_eblocks, uint, 0444); |
| 189 | MODULE_PARM_DESC(spare_eblocks, "Percentage of spare erase blocks for " |
| 190 | "garbage collection (default 10%)"); |
| 191 | |
| 192 | static bool header; /* false */ |
| 193 | module_param(header, bool, 0444); |
| 194 | MODULE_PARM_DESC(header, |
| 195 | "Include builtin swap header (default 0, without header)"); |
| 196 | |
| 197 | static int mtdswap_gc(struct mtdswap_dev *d, unsigned int background); |
| 198 | |
| 199 | static loff_t mtdswap_eb_offset(struct mtdswap_dev *d, struct swap_eb *eb) |
| 200 | { |
| 201 | return (loff_t)(eb - d->eb_data) * d->mtd->erasesize; |
| 202 | } |
| 203 | |
| 204 | static void mtdswap_eb_detach(struct mtdswap_dev *d, struct swap_eb *eb) |
| 205 | { |
| 206 | unsigned int oldidx; |
| 207 | struct mtdswap_tree *tp; |
| 208 | |
| 209 | if (eb->root) { |
| 210 | tp = container_of(eb->root, struct mtdswap_tree, root); |
| 211 | oldidx = tp - &d->trees[0]; |
| 212 | |
| 213 | d->trees[oldidx].count--; |
| 214 | rb_erase(&eb->rb, eb->root); |
| 215 | } |
| 216 | } |
| 217 | |
| 218 | static void __mtdswap_rb_add(struct rb_root *root, struct swap_eb *eb) |
| 219 | { |
| 220 | struct rb_node **p, *parent = NULL; |
| 221 | struct swap_eb *cur; |
| 222 | |
| 223 | p = &root->rb_node; |
| 224 | while (*p) { |
| 225 | parent = *p; |
| 226 | cur = rb_entry(parent, struct swap_eb, rb); |
| 227 | if (eb->erase_count > cur->erase_count) |
| 228 | p = &(*p)->rb_right; |
| 229 | else |
| 230 | p = &(*p)->rb_left; |
| 231 | } |
| 232 | |
| 233 | rb_link_node(&eb->rb, parent, p); |
| 234 | rb_insert_color(&eb->rb, root); |
| 235 | } |
| 236 | |
| 237 | static void mtdswap_rb_add(struct mtdswap_dev *d, struct swap_eb *eb, int idx) |
| 238 | { |
| 239 | struct rb_root *root; |
| 240 | |
| 241 | if (eb->root == &d->trees[idx].root) |
| 242 | return; |
| 243 | |
| 244 | mtdswap_eb_detach(d, eb); |
| 245 | root = &d->trees[idx].root; |
| 246 | __mtdswap_rb_add(root, eb); |
| 247 | eb->root = root; |
| 248 | d->trees[idx].count++; |
| 249 | } |
| 250 | |
| 251 | static struct rb_node *mtdswap_rb_index(struct rb_root *root, unsigned int idx) |
| 252 | { |
| 253 | struct rb_node *p; |
| 254 | unsigned int i; |
| 255 | |
| 256 | p = rb_first(root); |
| 257 | i = 0; |
| 258 | while (i < idx && p) { |
| 259 | p = rb_next(p); |
| 260 | i++; |
| 261 | } |
| 262 | |
| 263 | return p; |
| 264 | } |
| 265 | |
| 266 | static int mtdswap_handle_badblock(struct mtdswap_dev *d, struct swap_eb *eb) |
| 267 | { |
| 268 | int ret; |
| 269 | loff_t offset; |
| 270 | |
| 271 | d->spare_eblks--; |
| 272 | eb->flags |= EBLOCK_BAD; |
| 273 | mtdswap_eb_detach(d, eb); |
| 274 | eb->root = NULL; |
| 275 | |
| 276 | /* badblocks not supported */ |
Artem Bityutskiy | 800ffd3 | 2012-01-02 13:59:12 +0200 | [diff] [blame] | 277 | if (!mtd_can_have_bb(d->mtd)) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 278 | return 1; |
| 279 | |
| 280 | offset = mtdswap_eb_offset(d, eb); |
| 281 | dev_warn(d->dev, "Marking bad block at %08llx\n", offset); |
Artem Bityutskiy | 5942ddb | 2011-12-23 19:37:38 +0200 | [diff] [blame] | 282 | ret = mtd_block_markbad(d->mtd, offset); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 283 | |
| 284 | if (ret) { |
| 285 | dev_warn(d->dev, "Mark block bad failed for block at %08llx " |
| 286 | "error %d\n", offset, ret); |
| 287 | return ret; |
| 288 | } |
| 289 | |
| 290 | return 1; |
| 291 | |
| 292 | } |
| 293 | |
| 294 | static int mtdswap_handle_write_error(struct mtdswap_dev *d, struct swap_eb *eb) |
| 295 | { |
| 296 | unsigned int marked = eb->flags & EBLOCK_FAILED; |
| 297 | struct swap_eb *curr_write = d->curr_write; |
| 298 | |
| 299 | eb->flags |= EBLOCK_FAILED; |
| 300 | if (curr_write == eb) { |
| 301 | d->curr_write = NULL; |
| 302 | |
| 303 | if (!marked && d->curr_write_pos != 0) { |
| 304 | mtdswap_rb_add(d, eb, MTDSWAP_FAILING); |
| 305 | return 0; |
| 306 | } |
| 307 | } |
| 308 | |
| 309 | return mtdswap_handle_badblock(d, eb); |
| 310 | } |
| 311 | |
| 312 | static int mtdswap_read_oob(struct mtdswap_dev *d, loff_t from, |
| 313 | struct mtd_oob_ops *ops) |
| 314 | { |
Artem Bityutskiy | fd2819b | 2011-12-23 18:27:05 +0200 | [diff] [blame] | 315 | int ret = mtd_read_oob(d->mtd, from, ops); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 316 | |
Brian Norris | d57f4054 | 2011-09-20 18:34:25 -0700 | [diff] [blame] | 317 | if (mtd_is_bitflip(ret)) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 318 | return ret; |
| 319 | |
| 320 | if (ret) { |
| 321 | dev_warn(d->dev, "Read OOB failed %d for block at %08llx\n", |
| 322 | ret, from); |
| 323 | return ret; |
| 324 | } |
| 325 | |
| 326 | if (ops->oobretlen < ops->ooblen) { |
| 327 | dev_warn(d->dev, "Read OOB return short read (%zd bytes not " |
David Woodhouse | 89d8d32 | 2011-03-11 15:17:41 +0000 | [diff] [blame] | 328 | "%zd) for block at %08llx\n", |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 329 | ops->oobretlen, ops->ooblen, from); |
| 330 | return -EIO; |
| 331 | } |
| 332 | |
| 333 | return 0; |
| 334 | } |
| 335 | |
| 336 | static int mtdswap_read_markers(struct mtdswap_dev *d, struct swap_eb *eb) |
| 337 | { |
| 338 | struct mtdswap_oobdata *data, *data2; |
| 339 | int ret; |
| 340 | loff_t offset; |
| 341 | struct mtd_oob_ops ops; |
| 342 | |
| 343 | offset = mtdswap_eb_offset(d, eb); |
| 344 | |
| 345 | /* Check first if the block is bad. */ |
Artem Bityutskiy | 8f461a7 | 2012-01-02 13:48:54 +0200 | [diff] [blame] | 346 | if (mtd_can_have_bb(d->mtd) && mtd_block_isbad(d->mtd, offset)) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 347 | return MTDSWAP_SCANNED_BAD; |
| 348 | |
Boris BREZILLON | f5b8aa7 | 2016-03-07 10:46:51 +0100 | [diff] [blame] | 349 | ops.ooblen = 2 * d->mtd->oobavail; |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 350 | ops.oobbuf = d->oob_buf; |
| 351 | ops.ooboffs = 0; |
| 352 | ops.datbuf = NULL; |
Brian Norris | 0612b9d | 2011-08-30 18:45:40 -0700 | [diff] [blame] | 353 | ops.mode = MTD_OPS_AUTO_OOB; |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 354 | |
| 355 | ret = mtdswap_read_oob(d, offset, &ops); |
| 356 | |
Brian Norris | d57f4054 | 2011-09-20 18:34:25 -0700 | [diff] [blame] | 357 | if (ret && !mtd_is_bitflip(ret)) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 358 | return ret; |
| 359 | |
| 360 | data = (struct mtdswap_oobdata *)d->oob_buf; |
| 361 | data2 = (struct mtdswap_oobdata *) |
Boris BREZILLON | f5b8aa7 | 2016-03-07 10:46:51 +0100 | [diff] [blame] | 362 | (d->oob_buf + d->mtd->oobavail); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 363 | |
| 364 | if (le16_to_cpu(data->magic) == MTDSWAP_MAGIC_CLEAN) { |
| 365 | eb->erase_count = le32_to_cpu(data->count); |
Brian Norris | d57f4054 | 2011-09-20 18:34:25 -0700 | [diff] [blame] | 366 | if (mtd_is_bitflip(ret)) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 367 | ret = MTDSWAP_SCANNED_BITFLIP; |
| 368 | else { |
| 369 | if (le16_to_cpu(data2->magic) == MTDSWAP_MAGIC_DIRTY) |
| 370 | ret = MTDSWAP_SCANNED_DIRTY; |
| 371 | else |
| 372 | ret = MTDSWAP_SCANNED_CLEAN; |
| 373 | } |
| 374 | } else { |
| 375 | eb->flags |= EBLOCK_NOMAGIC; |
| 376 | ret = MTDSWAP_SCANNED_DIRTY; |
| 377 | } |
| 378 | |
| 379 | return ret; |
| 380 | } |
| 381 | |
| 382 | static int mtdswap_write_marker(struct mtdswap_dev *d, struct swap_eb *eb, |
| 383 | u16 marker) |
| 384 | { |
| 385 | struct mtdswap_oobdata n; |
| 386 | int ret; |
| 387 | loff_t offset; |
| 388 | struct mtd_oob_ops ops; |
| 389 | |
| 390 | ops.ooboffs = 0; |
| 391 | ops.oobbuf = (uint8_t *)&n; |
Brian Norris | 0612b9d | 2011-08-30 18:45:40 -0700 | [diff] [blame] | 392 | ops.mode = MTD_OPS_AUTO_OOB; |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 393 | ops.datbuf = NULL; |
| 394 | |
| 395 | if (marker == MTDSWAP_TYPE_CLEAN) { |
| 396 | n.magic = cpu_to_le16(MTDSWAP_MAGIC_CLEAN); |
| 397 | n.count = cpu_to_le32(eb->erase_count); |
| 398 | ops.ooblen = MTDSWAP_OOBSIZE; |
| 399 | offset = mtdswap_eb_offset(d, eb); |
| 400 | } else { |
| 401 | n.magic = cpu_to_le16(MTDSWAP_MAGIC_DIRTY); |
| 402 | ops.ooblen = sizeof(n.magic); |
| 403 | offset = mtdswap_eb_offset(d, eb) + d->mtd->writesize; |
| 404 | } |
| 405 | |
Artem Bityutskiy | a2cc5ba | 2011-12-23 18:29:55 +0200 | [diff] [blame] | 406 | ret = mtd_write_oob(d->mtd, offset, &ops); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 407 | |
| 408 | if (ret) { |
| 409 | dev_warn(d->dev, "Write OOB failed for block at %08llx " |
| 410 | "error %d\n", offset, ret); |
Brian Norris | d57f4054 | 2011-09-20 18:34:25 -0700 | [diff] [blame] | 411 | if (ret == -EIO || mtd_is_eccerr(ret)) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 412 | mtdswap_handle_write_error(d, eb); |
| 413 | return ret; |
| 414 | } |
| 415 | |
| 416 | if (ops.oobretlen != ops.ooblen) { |
| 417 | dev_warn(d->dev, "Short OOB write for block at %08llx: " |
David Woodhouse | 89d8d32 | 2011-03-11 15:17:41 +0000 | [diff] [blame] | 418 | "%zd not %zd\n", |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 419 | offset, ops.oobretlen, ops.ooblen); |
| 420 | return ret; |
| 421 | } |
| 422 | |
| 423 | return 0; |
| 424 | } |
| 425 | |
| 426 | /* |
| 427 | * Are there any erase blocks without MAGIC_CLEAN header, presumably |
| 428 | * because power was cut off after erase but before header write? We |
| 429 | * need to guestimate the erase count. |
| 430 | */ |
| 431 | static void mtdswap_check_counts(struct mtdswap_dev *d) |
| 432 | { |
| 433 | struct rb_root hist_root = RB_ROOT; |
| 434 | struct rb_node *medrb; |
| 435 | struct swap_eb *eb; |
| 436 | unsigned int i, cnt, median; |
| 437 | |
| 438 | cnt = 0; |
| 439 | for (i = 0; i < d->eblks; i++) { |
| 440 | eb = d->eb_data + i; |
| 441 | |
| 442 | if (eb->flags & (EBLOCK_NOMAGIC | EBLOCK_BAD | EBLOCK_READERR)) |
| 443 | continue; |
| 444 | |
| 445 | __mtdswap_rb_add(&hist_root, eb); |
| 446 | cnt++; |
| 447 | } |
| 448 | |
| 449 | if (cnt == 0) |
| 450 | return; |
| 451 | |
| 452 | medrb = mtdswap_rb_index(&hist_root, cnt / 2); |
| 453 | median = rb_entry(medrb, struct swap_eb, rb)->erase_count; |
| 454 | |
| 455 | d->max_erase_count = MTDSWAP_ECNT_MAX(&hist_root); |
| 456 | |
| 457 | for (i = 0; i < d->eblks; i++) { |
| 458 | eb = d->eb_data + i; |
| 459 | |
| 460 | if (eb->flags & (EBLOCK_NOMAGIC | EBLOCK_READERR)) |
| 461 | eb->erase_count = median; |
| 462 | |
| 463 | if (eb->flags & (EBLOCK_NOMAGIC | EBLOCK_BAD | EBLOCK_READERR)) |
| 464 | continue; |
| 465 | |
| 466 | rb_erase(&eb->rb, &hist_root); |
| 467 | } |
| 468 | } |
| 469 | |
| 470 | static void mtdswap_scan_eblks(struct mtdswap_dev *d) |
| 471 | { |
| 472 | int status; |
| 473 | unsigned int i, idx; |
| 474 | struct swap_eb *eb; |
| 475 | |
| 476 | for (i = 0; i < d->eblks; i++) { |
| 477 | eb = d->eb_data + i; |
| 478 | |
| 479 | status = mtdswap_read_markers(d, eb); |
| 480 | if (status < 0) |
| 481 | eb->flags |= EBLOCK_READERR; |
| 482 | else if (status == MTDSWAP_SCANNED_BAD) { |
| 483 | eb->flags |= EBLOCK_BAD; |
| 484 | continue; |
| 485 | } |
| 486 | |
| 487 | switch (status) { |
| 488 | case MTDSWAP_SCANNED_CLEAN: |
| 489 | idx = MTDSWAP_CLEAN; |
| 490 | break; |
| 491 | case MTDSWAP_SCANNED_DIRTY: |
| 492 | case MTDSWAP_SCANNED_BITFLIP: |
| 493 | idx = MTDSWAP_DIRTY; |
| 494 | break; |
| 495 | default: |
| 496 | idx = MTDSWAP_FAILING; |
| 497 | } |
| 498 | |
| 499 | eb->flags |= (idx << EBLOCK_IDX_SHIFT); |
| 500 | } |
| 501 | |
| 502 | mtdswap_check_counts(d); |
| 503 | |
| 504 | for (i = 0; i < d->eblks; i++) { |
| 505 | eb = d->eb_data + i; |
| 506 | |
| 507 | if (eb->flags & EBLOCK_BAD) |
| 508 | continue; |
| 509 | |
| 510 | idx = eb->flags >> EBLOCK_IDX_SHIFT; |
| 511 | mtdswap_rb_add(d, eb, idx); |
| 512 | } |
| 513 | } |
| 514 | |
| 515 | /* |
| 516 | * Place eblk into a tree corresponding to its number of active blocks |
| 517 | * it contains. |
| 518 | */ |
| 519 | static void mtdswap_store_eb(struct mtdswap_dev *d, struct swap_eb *eb) |
| 520 | { |
| 521 | unsigned int weight = eb->active_count; |
| 522 | unsigned int maxweight = d->pages_per_eblk; |
| 523 | |
| 524 | if (eb == d->curr_write) |
| 525 | return; |
| 526 | |
| 527 | if (eb->flags & EBLOCK_BITFLIP) |
| 528 | mtdswap_rb_add(d, eb, MTDSWAP_BITFLIP); |
| 529 | else if (eb->flags & (EBLOCK_READERR | EBLOCK_FAILED)) |
| 530 | mtdswap_rb_add(d, eb, MTDSWAP_FAILING); |
| 531 | if (weight == maxweight) |
| 532 | mtdswap_rb_add(d, eb, MTDSWAP_USED); |
| 533 | else if (weight == 0) |
| 534 | mtdswap_rb_add(d, eb, MTDSWAP_DIRTY); |
| 535 | else if (weight > (maxweight/2)) |
| 536 | mtdswap_rb_add(d, eb, MTDSWAP_LOWFRAG); |
| 537 | else |
| 538 | mtdswap_rb_add(d, eb, MTDSWAP_HIFRAG); |
| 539 | } |
| 540 | |
| 541 | |
| 542 | static void mtdswap_erase_callback(struct erase_info *done) |
| 543 | { |
| 544 | wait_queue_head_t *wait_q = (wait_queue_head_t *)done->priv; |
| 545 | wake_up(wait_q); |
| 546 | } |
| 547 | |
| 548 | static int mtdswap_erase_block(struct mtdswap_dev *d, struct swap_eb *eb) |
| 549 | { |
| 550 | struct mtd_info *mtd = d->mtd; |
| 551 | struct erase_info erase; |
| 552 | wait_queue_head_t wq; |
| 553 | unsigned int retries = 0; |
| 554 | int ret; |
| 555 | |
| 556 | eb->erase_count++; |
| 557 | if (eb->erase_count > d->max_erase_count) |
| 558 | d->max_erase_count = eb->erase_count; |
| 559 | |
| 560 | retry: |
| 561 | init_waitqueue_head(&wq); |
| 562 | memset(&erase, 0, sizeof(struct erase_info)); |
| 563 | |
| 564 | erase.mtd = mtd; |
| 565 | erase.callback = mtdswap_erase_callback; |
| 566 | erase.addr = mtdswap_eb_offset(d, eb); |
| 567 | erase.len = mtd->erasesize; |
| 568 | erase.priv = (u_long)&wq; |
| 569 | |
Artem Bityutskiy | 7e1f0dc | 2011-12-23 15:25:39 +0200 | [diff] [blame] | 570 | ret = mtd_erase(mtd, &erase); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 571 | if (ret) { |
Yang Ruirui | e21fa86 | 2011-03-14 09:50:56 +0800 | [diff] [blame] | 572 | if (retries++ < MTDSWAP_ERASE_RETRIES) { |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 573 | dev_warn(d->dev, |
| 574 | "erase of erase block %#llx on %s failed", |
| 575 | erase.addr, mtd->name); |
| 576 | yield(); |
| 577 | goto retry; |
| 578 | } |
| 579 | |
| 580 | dev_err(d->dev, "Cannot erase erase block %#llx on %s\n", |
| 581 | erase.addr, mtd->name); |
| 582 | |
| 583 | mtdswap_handle_badblock(d, eb); |
| 584 | return -EIO; |
| 585 | } |
| 586 | |
| 587 | ret = wait_event_interruptible(wq, erase.state == MTD_ERASE_DONE || |
| 588 | erase.state == MTD_ERASE_FAILED); |
| 589 | if (ret) { |
| 590 | dev_err(d->dev, "Interrupted erase block %#llx erassure on %s", |
| 591 | erase.addr, mtd->name); |
| 592 | return -EINTR; |
| 593 | } |
| 594 | |
| 595 | if (erase.state == MTD_ERASE_FAILED) { |
| 596 | if (retries++ < MTDSWAP_ERASE_RETRIES) { |
| 597 | dev_warn(d->dev, |
| 598 | "erase of erase block %#llx on %s failed", |
| 599 | erase.addr, mtd->name); |
| 600 | yield(); |
| 601 | goto retry; |
| 602 | } |
| 603 | |
| 604 | mtdswap_handle_badblock(d, eb); |
| 605 | return -EIO; |
| 606 | } |
| 607 | |
| 608 | return 0; |
| 609 | } |
| 610 | |
| 611 | static int mtdswap_map_free_block(struct mtdswap_dev *d, unsigned int page, |
| 612 | unsigned int *block) |
| 613 | { |
| 614 | int ret; |
| 615 | struct swap_eb *old_eb = d->curr_write; |
| 616 | struct rb_root *clean_root; |
| 617 | struct swap_eb *eb; |
| 618 | |
| 619 | if (old_eb == NULL || d->curr_write_pos >= d->pages_per_eblk) { |
| 620 | do { |
| 621 | if (TREE_EMPTY(d, CLEAN)) |
| 622 | return -ENOSPC; |
| 623 | |
| 624 | clean_root = TREE_ROOT(d, CLEAN); |
| 625 | eb = rb_entry(rb_first(clean_root), struct swap_eb, rb); |
| 626 | rb_erase(&eb->rb, clean_root); |
| 627 | eb->root = NULL; |
| 628 | TREE_COUNT(d, CLEAN)--; |
| 629 | |
| 630 | ret = mtdswap_write_marker(d, eb, MTDSWAP_TYPE_DIRTY); |
Brian Norris | d57f4054 | 2011-09-20 18:34:25 -0700 | [diff] [blame] | 631 | } while (ret == -EIO || mtd_is_eccerr(ret)); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 632 | |
| 633 | if (ret) |
| 634 | return ret; |
| 635 | |
| 636 | d->curr_write_pos = 0; |
| 637 | d->curr_write = eb; |
| 638 | if (old_eb) |
| 639 | mtdswap_store_eb(d, old_eb); |
| 640 | } |
| 641 | |
| 642 | *block = (d->curr_write - d->eb_data) * d->pages_per_eblk + |
| 643 | d->curr_write_pos; |
| 644 | |
| 645 | d->curr_write->active_count++; |
| 646 | d->revmap[*block] = page; |
| 647 | d->curr_write_pos++; |
| 648 | |
| 649 | return 0; |
| 650 | } |
| 651 | |
| 652 | static unsigned int mtdswap_free_page_cnt(struct mtdswap_dev *d) |
| 653 | { |
| 654 | return TREE_COUNT(d, CLEAN) * d->pages_per_eblk + |
| 655 | d->pages_per_eblk - d->curr_write_pos; |
| 656 | } |
| 657 | |
| 658 | static unsigned int mtdswap_enough_free_pages(struct mtdswap_dev *d) |
| 659 | { |
| 660 | return mtdswap_free_page_cnt(d) > d->pages_per_eblk; |
| 661 | } |
| 662 | |
| 663 | static int mtdswap_write_block(struct mtdswap_dev *d, char *buf, |
| 664 | unsigned int page, unsigned int *bp, int gc_context) |
| 665 | { |
| 666 | struct mtd_info *mtd = d->mtd; |
| 667 | struct swap_eb *eb; |
| 668 | size_t retlen; |
| 669 | loff_t writepos; |
| 670 | int ret; |
| 671 | |
| 672 | retry: |
| 673 | if (!gc_context) |
| 674 | while (!mtdswap_enough_free_pages(d)) |
| 675 | if (mtdswap_gc(d, 0) > 0) |
| 676 | return -ENOSPC; |
| 677 | |
| 678 | ret = mtdswap_map_free_block(d, page, bp); |
| 679 | eb = d->eb_data + (*bp / d->pages_per_eblk); |
| 680 | |
Brian Norris | d57f4054 | 2011-09-20 18:34:25 -0700 | [diff] [blame] | 681 | if (ret == -EIO || mtd_is_eccerr(ret)) { |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 682 | d->curr_write = NULL; |
| 683 | eb->active_count--; |
| 684 | d->revmap[*bp] = PAGE_UNDEF; |
| 685 | goto retry; |
| 686 | } |
| 687 | |
| 688 | if (ret < 0) |
| 689 | return ret; |
| 690 | |
| 691 | writepos = (loff_t)*bp << PAGE_SHIFT; |
Artem Bityutskiy | eda95cb | 2011-12-23 17:35:41 +0200 | [diff] [blame] | 692 | ret = mtd_write(mtd, writepos, PAGE_SIZE, &retlen, buf); |
Brian Norris | d57f4054 | 2011-09-20 18:34:25 -0700 | [diff] [blame] | 693 | if (ret == -EIO || mtd_is_eccerr(ret)) { |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 694 | d->curr_write_pos--; |
| 695 | eb->active_count--; |
| 696 | d->revmap[*bp] = PAGE_UNDEF; |
| 697 | mtdswap_handle_write_error(d, eb); |
| 698 | goto retry; |
| 699 | } |
| 700 | |
| 701 | if (ret < 0) { |
David Woodhouse | 89d8d32 | 2011-03-11 15:17:41 +0000 | [diff] [blame] | 702 | dev_err(d->dev, "Write to MTD device failed: %d (%zd written)", |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 703 | ret, retlen); |
| 704 | goto err; |
| 705 | } |
| 706 | |
| 707 | if (retlen != PAGE_SIZE) { |
David Woodhouse | 89d8d32 | 2011-03-11 15:17:41 +0000 | [diff] [blame] | 708 | dev_err(d->dev, "Short write to MTD device: %zd written", |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 709 | retlen); |
| 710 | ret = -EIO; |
| 711 | goto err; |
| 712 | } |
| 713 | |
| 714 | return ret; |
| 715 | |
| 716 | err: |
| 717 | d->curr_write_pos--; |
| 718 | eb->active_count--; |
| 719 | d->revmap[*bp] = PAGE_UNDEF; |
| 720 | |
| 721 | return ret; |
| 722 | } |
| 723 | |
| 724 | static int mtdswap_move_block(struct mtdswap_dev *d, unsigned int oldblock, |
| 725 | unsigned int *newblock) |
| 726 | { |
| 727 | struct mtd_info *mtd = d->mtd; |
| 728 | struct swap_eb *eb, *oldeb; |
| 729 | int ret; |
| 730 | size_t retlen; |
| 731 | unsigned int page, retries; |
| 732 | loff_t readpos; |
| 733 | |
| 734 | page = d->revmap[oldblock]; |
| 735 | readpos = (loff_t) oldblock << PAGE_SHIFT; |
| 736 | retries = 0; |
| 737 | |
| 738 | retry: |
Artem Bityutskiy | 329ad39 | 2011-12-23 17:30:16 +0200 | [diff] [blame] | 739 | ret = mtd_read(mtd, readpos, PAGE_SIZE, &retlen, d->page_buf); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 740 | |
Brian Norris | d57f4054 | 2011-09-20 18:34:25 -0700 | [diff] [blame] | 741 | if (ret < 0 && !mtd_is_bitflip(ret)) { |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 742 | oldeb = d->eb_data + oldblock / d->pages_per_eblk; |
| 743 | oldeb->flags |= EBLOCK_READERR; |
| 744 | |
| 745 | dev_err(d->dev, "Read Error: %d (block %u)\n", ret, |
| 746 | oldblock); |
| 747 | retries++; |
| 748 | if (retries < MTDSWAP_IO_RETRIES) |
| 749 | goto retry; |
| 750 | |
| 751 | goto read_error; |
| 752 | } |
| 753 | |
| 754 | if (retlen != PAGE_SIZE) { |
David Woodhouse | 89d8d32 | 2011-03-11 15:17:41 +0000 | [diff] [blame] | 755 | dev_err(d->dev, "Short read: %zd (block %u)\n", retlen, |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 756 | oldblock); |
| 757 | ret = -EIO; |
| 758 | goto read_error; |
| 759 | } |
| 760 | |
| 761 | ret = mtdswap_write_block(d, d->page_buf, page, newblock, 1); |
| 762 | if (ret < 0) { |
| 763 | d->page_data[page] = BLOCK_ERROR; |
| 764 | dev_err(d->dev, "Write error: %d\n", ret); |
| 765 | return ret; |
| 766 | } |
| 767 | |
| 768 | eb = d->eb_data + *newblock / d->pages_per_eblk; |
| 769 | d->page_data[page] = *newblock; |
| 770 | d->revmap[oldblock] = PAGE_UNDEF; |
| 771 | eb = d->eb_data + oldblock / d->pages_per_eblk; |
| 772 | eb->active_count--; |
| 773 | |
| 774 | return 0; |
| 775 | |
| 776 | read_error: |
| 777 | d->page_data[page] = BLOCK_ERROR; |
| 778 | d->revmap[oldblock] = PAGE_UNDEF; |
| 779 | return ret; |
| 780 | } |
| 781 | |
| 782 | static int mtdswap_gc_eblock(struct mtdswap_dev *d, struct swap_eb *eb) |
| 783 | { |
| 784 | unsigned int i, block, eblk_base, newblock; |
| 785 | int ret, errcode; |
| 786 | |
| 787 | errcode = 0; |
| 788 | eblk_base = (eb - d->eb_data) * d->pages_per_eblk; |
| 789 | |
| 790 | for (i = 0; i < d->pages_per_eblk; i++) { |
| 791 | if (d->spare_eblks < MIN_SPARE_EBLOCKS) |
| 792 | return -ENOSPC; |
| 793 | |
| 794 | block = eblk_base + i; |
| 795 | if (d->revmap[block] == PAGE_UNDEF) |
| 796 | continue; |
| 797 | |
| 798 | ret = mtdswap_move_block(d, block, &newblock); |
| 799 | if (ret < 0 && !errcode) |
| 800 | errcode = ret; |
| 801 | } |
| 802 | |
| 803 | return errcode; |
| 804 | } |
| 805 | |
| 806 | static int __mtdswap_choose_gc_tree(struct mtdswap_dev *d) |
| 807 | { |
| 808 | int idx, stopat; |
| 809 | |
| 810 | if (TREE_COUNT(d, CLEAN) < LOW_FRAG_GC_TRESHOLD) |
| 811 | stopat = MTDSWAP_LOWFRAG; |
| 812 | else |
| 813 | stopat = MTDSWAP_HIFRAG; |
| 814 | |
| 815 | for (idx = MTDSWAP_BITFLIP; idx >= stopat; idx--) |
| 816 | if (d->trees[idx].root.rb_node != NULL) |
| 817 | return idx; |
| 818 | |
| 819 | return -1; |
| 820 | } |
| 821 | |
| 822 | static int mtdswap_wlfreq(unsigned int maxdiff) |
| 823 | { |
| 824 | unsigned int h, x, y, dist, base; |
| 825 | |
| 826 | /* |
| 827 | * Calculate linear ramp down from f1 to f2 when maxdiff goes from |
| 828 | * MAX_ERASE_DIFF to MAX_ERASE_DIFF + COLLECT_NONDIRTY_BASE. Similar |
| 829 | * to triangle with height f1 - f1 and width COLLECT_NONDIRTY_BASE. |
| 830 | */ |
| 831 | |
| 832 | dist = maxdiff - MAX_ERASE_DIFF; |
| 833 | if (dist > COLLECT_NONDIRTY_BASE) |
| 834 | dist = COLLECT_NONDIRTY_BASE; |
| 835 | |
| 836 | /* |
| 837 | * Modelling the slop as right angular triangle with base |
| 838 | * COLLECT_NONDIRTY_BASE and height freq1 - freq2. The ratio y/x is |
| 839 | * equal to the ratio h/base. |
| 840 | */ |
| 841 | h = COLLECT_NONDIRTY_FREQ1 - COLLECT_NONDIRTY_FREQ2; |
| 842 | base = COLLECT_NONDIRTY_BASE; |
| 843 | |
| 844 | x = dist - base; |
| 845 | y = (x * h + base / 2) / base; |
| 846 | |
| 847 | return COLLECT_NONDIRTY_FREQ2 + y; |
| 848 | } |
| 849 | |
| 850 | static int mtdswap_choose_wl_tree(struct mtdswap_dev *d) |
| 851 | { |
| 852 | static unsigned int pick_cnt; |
Artem Bityutskiy | 68b1a1e | 2011-03-25 17:10:16 +0200 | [diff] [blame] | 853 | unsigned int i, idx = -1, wear, max; |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 854 | struct rb_root *root; |
| 855 | |
| 856 | max = 0; |
| 857 | for (i = 0; i <= MTDSWAP_DIRTY; i++) { |
| 858 | root = &d->trees[i].root; |
| 859 | if (root->rb_node == NULL) |
| 860 | continue; |
| 861 | |
| 862 | wear = d->max_erase_count - MTDSWAP_ECNT_MIN(root); |
| 863 | if (wear > max) { |
| 864 | max = wear; |
| 865 | idx = i; |
| 866 | } |
| 867 | } |
| 868 | |
| 869 | if (max > MAX_ERASE_DIFF && pick_cnt >= mtdswap_wlfreq(max) - 1) { |
| 870 | pick_cnt = 0; |
| 871 | return idx; |
| 872 | } |
| 873 | |
| 874 | pick_cnt++; |
| 875 | return -1; |
| 876 | } |
| 877 | |
| 878 | static int mtdswap_choose_gc_tree(struct mtdswap_dev *d, |
| 879 | unsigned int background) |
| 880 | { |
| 881 | int idx; |
| 882 | |
| 883 | if (TREE_NONEMPTY(d, FAILING) && |
| 884 | (background || (TREE_EMPTY(d, CLEAN) && TREE_EMPTY(d, DIRTY)))) |
| 885 | return MTDSWAP_FAILING; |
| 886 | |
| 887 | idx = mtdswap_choose_wl_tree(d); |
| 888 | if (idx >= MTDSWAP_CLEAN) |
| 889 | return idx; |
| 890 | |
| 891 | return __mtdswap_choose_gc_tree(d); |
| 892 | } |
| 893 | |
| 894 | static struct swap_eb *mtdswap_pick_gc_eblk(struct mtdswap_dev *d, |
| 895 | unsigned int background) |
| 896 | { |
| 897 | struct rb_root *rp = NULL; |
| 898 | struct swap_eb *eb = NULL; |
| 899 | int idx; |
| 900 | |
| 901 | if (background && TREE_COUNT(d, CLEAN) > CLEAN_BLOCK_THRESHOLD && |
| 902 | TREE_EMPTY(d, DIRTY) && TREE_EMPTY(d, FAILING)) |
| 903 | return NULL; |
| 904 | |
| 905 | idx = mtdswap_choose_gc_tree(d, background); |
| 906 | if (idx < 0) |
| 907 | return NULL; |
| 908 | |
| 909 | rp = &d->trees[idx].root; |
| 910 | eb = rb_entry(rb_first(rp), struct swap_eb, rb); |
| 911 | |
| 912 | rb_erase(&eb->rb, rp); |
| 913 | eb->root = NULL; |
| 914 | d->trees[idx].count--; |
| 915 | return eb; |
| 916 | } |
| 917 | |
| 918 | static unsigned int mtdswap_test_patt(unsigned int i) |
| 919 | { |
| 920 | return i % 2 ? 0x55555555 : 0xAAAAAAAA; |
| 921 | } |
| 922 | |
| 923 | static unsigned int mtdswap_eblk_passes(struct mtdswap_dev *d, |
| 924 | struct swap_eb *eb) |
| 925 | { |
| 926 | struct mtd_info *mtd = d->mtd; |
| 927 | unsigned int test, i, j, patt, mtd_pages; |
| 928 | loff_t base, pos; |
| 929 | unsigned int *p1 = (unsigned int *)d->page_buf; |
| 930 | unsigned char *p2 = (unsigned char *)d->oob_buf; |
| 931 | struct mtd_oob_ops ops; |
| 932 | int ret; |
| 933 | |
Brian Norris | 0612b9d | 2011-08-30 18:45:40 -0700 | [diff] [blame] | 934 | ops.mode = MTD_OPS_AUTO_OOB; |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 935 | ops.len = mtd->writesize; |
Boris BREZILLON | f5b8aa7 | 2016-03-07 10:46:51 +0100 | [diff] [blame] | 936 | ops.ooblen = mtd->oobavail; |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 937 | ops.ooboffs = 0; |
| 938 | ops.datbuf = d->page_buf; |
| 939 | ops.oobbuf = d->oob_buf; |
| 940 | base = mtdswap_eb_offset(d, eb); |
| 941 | mtd_pages = d->pages_per_eblk * PAGE_SIZE / mtd->writesize; |
| 942 | |
| 943 | for (test = 0; test < 2; test++) { |
| 944 | pos = base; |
| 945 | for (i = 0; i < mtd_pages; i++) { |
| 946 | patt = mtdswap_test_patt(test + i); |
| 947 | memset(d->page_buf, patt, mtd->writesize); |
Boris BREZILLON | f5b8aa7 | 2016-03-07 10:46:51 +0100 | [diff] [blame] | 948 | memset(d->oob_buf, patt, mtd->oobavail); |
Artem Bityutskiy | a2cc5ba | 2011-12-23 18:29:55 +0200 | [diff] [blame] | 949 | ret = mtd_write_oob(mtd, pos, &ops); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 950 | if (ret) |
| 951 | goto error; |
| 952 | |
| 953 | pos += mtd->writesize; |
| 954 | } |
| 955 | |
| 956 | pos = base; |
| 957 | for (i = 0; i < mtd_pages; i++) { |
Artem Bityutskiy | fd2819b | 2011-12-23 18:27:05 +0200 | [diff] [blame] | 958 | ret = mtd_read_oob(mtd, pos, &ops); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 959 | if (ret) |
| 960 | goto error; |
| 961 | |
| 962 | patt = mtdswap_test_patt(test + i); |
| 963 | for (j = 0; j < mtd->writesize/sizeof(int); j++) |
| 964 | if (p1[j] != patt) |
| 965 | goto error; |
| 966 | |
Boris BREZILLON | f5b8aa7 | 2016-03-07 10:46:51 +0100 | [diff] [blame] | 967 | for (j = 0; j < mtd->oobavail; j++) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 968 | if (p2[j] != (unsigned char)patt) |
| 969 | goto error; |
| 970 | |
| 971 | pos += mtd->writesize; |
| 972 | } |
| 973 | |
| 974 | ret = mtdswap_erase_block(d, eb); |
| 975 | if (ret) |
| 976 | goto error; |
| 977 | } |
| 978 | |
| 979 | eb->flags &= ~EBLOCK_READERR; |
| 980 | return 1; |
| 981 | |
| 982 | error: |
| 983 | mtdswap_handle_badblock(d, eb); |
| 984 | return 0; |
| 985 | } |
| 986 | |
| 987 | static int mtdswap_gc(struct mtdswap_dev *d, unsigned int background) |
| 988 | { |
| 989 | struct swap_eb *eb; |
| 990 | int ret; |
| 991 | |
| 992 | if (d->spare_eblks < MIN_SPARE_EBLOCKS) |
| 993 | return 1; |
| 994 | |
| 995 | eb = mtdswap_pick_gc_eblk(d, background); |
| 996 | if (!eb) |
| 997 | return 1; |
| 998 | |
| 999 | ret = mtdswap_gc_eblock(d, eb); |
| 1000 | if (ret == -ENOSPC) |
| 1001 | return 1; |
| 1002 | |
| 1003 | if (eb->flags & EBLOCK_FAILED) { |
| 1004 | mtdswap_handle_badblock(d, eb); |
| 1005 | return 0; |
| 1006 | } |
| 1007 | |
| 1008 | eb->flags &= ~EBLOCK_BITFLIP; |
| 1009 | ret = mtdswap_erase_block(d, eb); |
| 1010 | if ((eb->flags & EBLOCK_READERR) && |
| 1011 | (ret || !mtdswap_eblk_passes(d, eb))) |
| 1012 | return 0; |
| 1013 | |
| 1014 | if (ret == 0) |
| 1015 | ret = mtdswap_write_marker(d, eb, MTDSWAP_TYPE_CLEAN); |
| 1016 | |
| 1017 | if (ret == 0) |
| 1018 | mtdswap_rb_add(d, eb, MTDSWAP_CLEAN); |
Brian Norris | d57f4054 | 2011-09-20 18:34:25 -0700 | [diff] [blame] | 1019 | else if (ret != -EIO && !mtd_is_eccerr(ret)) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1020 | mtdswap_rb_add(d, eb, MTDSWAP_DIRTY); |
| 1021 | |
| 1022 | return 0; |
| 1023 | } |
| 1024 | |
| 1025 | static void mtdswap_background(struct mtd_blktrans_dev *dev) |
| 1026 | { |
| 1027 | struct mtdswap_dev *d = MTDSWAP_MBD_TO_MTDSWAP(dev); |
| 1028 | int ret; |
| 1029 | |
| 1030 | while (1) { |
| 1031 | ret = mtdswap_gc(d, 1); |
| 1032 | if (ret || mtd_blktrans_cease_background(dev)) |
| 1033 | return; |
| 1034 | } |
| 1035 | } |
| 1036 | |
| 1037 | static void mtdswap_cleanup(struct mtdswap_dev *d) |
| 1038 | { |
| 1039 | vfree(d->eb_data); |
| 1040 | vfree(d->revmap); |
| 1041 | vfree(d->page_data); |
| 1042 | kfree(d->oob_buf); |
| 1043 | kfree(d->page_buf); |
| 1044 | } |
| 1045 | |
| 1046 | static int mtdswap_flush(struct mtd_blktrans_dev *dev) |
| 1047 | { |
| 1048 | struct mtdswap_dev *d = MTDSWAP_MBD_TO_MTDSWAP(dev); |
| 1049 | |
Artem Bityutskiy | 327cf29 | 2011-12-30 16:35:35 +0200 | [diff] [blame] | 1050 | mtd_sync(d->mtd); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1051 | return 0; |
| 1052 | } |
| 1053 | |
| 1054 | static unsigned int mtdswap_badblocks(struct mtd_info *mtd, uint64_t size) |
| 1055 | { |
| 1056 | loff_t offset; |
| 1057 | unsigned int badcnt; |
| 1058 | |
| 1059 | badcnt = 0; |
| 1060 | |
Artem Bityutskiy | 8f461a7 | 2012-01-02 13:48:54 +0200 | [diff] [blame] | 1061 | if (mtd_can_have_bb(mtd)) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1062 | for (offset = 0; offset < size; offset += mtd->erasesize) |
Artem Bityutskiy | 7086c19 | 2011-12-23 19:35:30 +0200 | [diff] [blame] | 1063 | if (mtd_block_isbad(mtd, offset)) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1064 | badcnt++; |
| 1065 | |
| 1066 | return badcnt; |
| 1067 | } |
| 1068 | |
| 1069 | static int mtdswap_writesect(struct mtd_blktrans_dev *dev, |
| 1070 | unsigned long page, char *buf) |
| 1071 | { |
| 1072 | struct mtdswap_dev *d = MTDSWAP_MBD_TO_MTDSWAP(dev); |
| 1073 | unsigned int newblock, mapped; |
| 1074 | struct swap_eb *eb; |
| 1075 | int ret; |
| 1076 | |
| 1077 | d->sect_write_count++; |
| 1078 | |
| 1079 | if (d->spare_eblks < MIN_SPARE_EBLOCKS) |
| 1080 | return -ENOSPC; |
| 1081 | |
| 1082 | if (header) { |
| 1083 | /* Ignore writes to the header page */ |
| 1084 | if (unlikely(page == 0)) |
| 1085 | return 0; |
| 1086 | |
| 1087 | page--; |
| 1088 | } |
| 1089 | |
| 1090 | mapped = d->page_data[page]; |
| 1091 | if (mapped <= BLOCK_MAX) { |
| 1092 | eb = d->eb_data + (mapped / d->pages_per_eblk); |
| 1093 | eb->active_count--; |
| 1094 | mtdswap_store_eb(d, eb); |
| 1095 | d->page_data[page] = BLOCK_UNDEF; |
| 1096 | d->revmap[mapped] = PAGE_UNDEF; |
| 1097 | } |
| 1098 | |
| 1099 | ret = mtdswap_write_block(d, buf, page, &newblock, 0); |
| 1100 | d->mtd_write_count++; |
| 1101 | |
| 1102 | if (ret < 0) |
| 1103 | return ret; |
| 1104 | |
| 1105 | eb = d->eb_data + (newblock / d->pages_per_eblk); |
| 1106 | d->page_data[page] = newblock; |
| 1107 | |
| 1108 | return 0; |
| 1109 | } |
| 1110 | |
| 1111 | /* Provide a dummy swap header for the kernel */ |
| 1112 | static int mtdswap_auto_header(struct mtdswap_dev *d, char *buf) |
| 1113 | { |
| 1114 | union swap_header *hd = (union swap_header *)(buf); |
| 1115 | |
| 1116 | memset(buf, 0, PAGE_SIZE - 10); |
| 1117 | |
| 1118 | hd->info.version = 1; |
| 1119 | hd->info.last_page = d->mbd_dev->size - 1; |
| 1120 | hd->info.nr_badpages = 0; |
| 1121 | |
| 1122 | memcpy(buf + PAGE_SIZE - 10, "SWAPSPACE2", 10); |
| 1123 | |
| 1124 | return 0; |
| 1125 | } |
| 1126 | |
| 1127 | static int mtdswap_readsect(struct mtd_blktrans_dev *dev, |
| 1128 | unsigned long page, char *buf) |
| 1129 | { |
| 1130 | struct mtdswap_dev *d = MTDSWAP_MBD_TO_MTDSWAP(dev); |
| 1131 | struct mtd_info *mtd = d->mtd; |
| 1132 | unsigned int realblock, retries; |
| 1133 | loff_t readpos; |
| 1134 | struct swap_eb *eb; |
| 1135 | size_t retlen; |
| 1136 | int ret; |
| 1137 | |
| 1138 | d->sect_read_count++; |
| 1139 | |
| 1140 | if (header) { |
| 1141 | if (unlikely(page == 0)) |
| 1142 | return mtdswap_auto_header(d, buf); |
| 1143 | |
| 1144 | page--; |
| 1145 | } |
| 1146 | |
| 1147 | realblock = d->page_data[page]; |
| 1148 | if (realblock > BLOCK_MAX) { |
| 1149 | memset(buf, 0x0, PAGE_SIZE); |
| 1150 | if (realblock == BLOCK_UNDEF) |
| 1151 | return 0; |
| 1152 | else |
| 1153 | return -EIO; |
| 1154 | } |
| 1155 | |
| 1156 | eb = d->eb_data + (realblock / d->pages_per_eblk); |
| 1157 | BUG_ON(d->revmap[realblock] == PAGE_UNDEF); |
| 1158 | |
| 1159 | readpos = (loff_t)realblock << PAGE_SHIFT; |
| 1160 | retries = 0; |
| 1161 | |
| 1162 | retry: |
Artem Bityutskiy | 329ad39 | 2011-12-23 17:30:16 +0200 | [diff] [blame] | 1163 | ret = mtd_read(mtd, readpos, PAGE_SIZE, &retlen, buf); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1164 | |
| 1165 | d->mtd_read_count++; |
Brian Norris | d57f4054 | 2011-09-20 18:34:25 -0700 | [diff] [blame] | 1166 | if (mtd_is_bitflip(ret)) { |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1167 | eb->flags |= EBLOCK_BITFLIP; |
| 1168 | mtdswap_rb_add(d, eb, MTDSWAP_BITFLIP); |
| 1169 | ret = 0; |
| 1170 | } |
| 1171 | |
| 1172 | if (ret < 0) { |
| 1173 | dev_err(d->dev, "Read error %d\n", ret); |
| 1174 | eb->flags |= EBLOCK_READERR; |
| 1175 | mtdswap_rb_add(d, eb, MTDSWAP_FAILING); |
| 1176 | retries++; |
| 1177 | if (retries < MTDSWAP_IO_RETRIES) |
| 1178 | goto retry; |
| 1179 | |
| 1180 | return ret; |
| 1181 | } |
| 1182 | |
| 1183 | if (retlen != PAGE_SIZE) { |
David Woodhouse | 89d8d32 | 2011-03-11 15:17:41 +0000 | [diff] [blame] | 1184 | dev_err(d->dev, "Short read %zd\n", retlen); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1185 | return -EIO; |
| 1186 | } |
| 1187 | |
| 1188 | return 0; |
| 1189 | } |
| 1190 | |
| 1191 | static int mtdswap_discard(struct mtd_blktrans_dev *dev, unsigned long first, |
| 1192 | unsigned nr_pages) |
| 1193 | { |
| 1194 | struct mtdswap_dev *d = MTDSWAP_MBD_TO_MTDSWAP(dev); |
| 1195 | unsigned long page; |
| 1196 | struct swap_eb *eb; |
| 1197 | unsigned int mapped; |
| 1198 | |
| 1199 | d->discard_count++; |
| 1200 | |
| 1201 | for (page = first; page < first + nr_pages; page++) { |
| 1202 | mapped = d->page_data[page]; |
| 1203 | if (mapped <= BLOCK_MAX) { |
| 1204 | eb = d->eb_data + (mapped / d->pages_per_eblk); |
| 1205 | eb->active_count--; |
| 1206 | mtdswap_store_eb(d, eb); |
| 1207 | d->page_data[page] = BLOCK_UNDEF; |
| 1208 | d->revmap[mapped] = PAGE_UNDEF; |
| 1209 | d->discard_page_count++; |
| 1210 | } else if (mapped == BLOCK_ERROR) { |
| 1211 | d->page_data[page] = BLOCK_UNDEF; |
| 1212 | d->discard_page_count++; |
| 1213 | } |
| 1214 | } |
| 1215 | |
| 1216 | return 0; |
| 1217 | } |
| 1218 | |
| 1219 | static int mtdswap_show(struct seq_file *s, void *data) |
| 1220 | { |
| 1221 | struct mtdswap_dev *d = (struct mtdswap_dev *) s->private; |
| 1222 | unsigned long sum; |
| 1223 | unsigned int count[MTDSWAP_TREE_CNT]; |
| 1224 | unsigned int min[MTDSWAP_TREE_CNT]; |
| 1225 | unsigned int max[MTDSWAP_TREE_CNT]; |
| 1226 | unsigned int i, cw = 0, cwp = 0, cwecount = 0, bb_cnt, mapped, pages; |
| 1227 | uint64_t use_size; |
| 1228 | char *name[] = {"clean", "used", "low", "high", "dirty", "bitflip", |
| 1229 | "failing"}; |
| 1230 | |
| 1231 | mutex_lock(&d->mbd_dev->lock); |
| 1232 | |
| 1233 | for (i = 0; i < MTDSWAP_TREE_CNT; i++) { |
| 1234 | struct rb_root *root = &d->trees[i].root; |
| 1235 | |
| 1236 | if (root->rb_node) { |
| 1237 | count[i] = d->trees[i].count; |
| 1238 | min[i] = rb_entry(rb_first(root), struct swap_eb, |
| 1239 | rb)->erase_count; |
| 1240 | max[i] = rb_entry(rb_last(root), struct swap_eb, |
| 1241 | rb)->erase_count; |
| 1242 | } else |
| 1243 | count[i] = 0; |
| 1244 | } |
| 1245 | |
| 1246 | if (d->curr_write) { |
| 1247 | cw = 1; |
| 1248 | cwp = d->curr_write_pos; |
| 1249 | cwecount = d->curr_write->erase_count; |
| 1250 | } |
| 1251 | |
| 1252 | sum = 0; |
| 1253 | for (i = 0; i < d->eblks; i++) |
| 1254 | sum += d->eb_data[i].erase_count; |
| 1255 | |
| 1256 | use_size = (uint64_t)d->eblks * d->mtd->erasesize; |
| 1257 | bb_cnt = mtdswap_badblocks(d->mtd, use_size); |
| 1258 | |
| 1259 | mapped = 0; |
| 1260 | pages = d->mbd_dev->size; |
| 1261 | for (i = 0; i < pages; i++) |
| 1262 | if (d->page_data[i] != BLOCK_UNDEF) |
| 1263 | mapped++; |
| 1264 | |
| 1265 | mutex_unlock(&d->mbd_dev->lock); |
| 1266 | |
| 1267 | for (i = 0; i < MTDSWAP_TREE_CNT; i++) { |
| 1268 | if (!count[i]) |
| 1269 | continue; |
| 1270 | |
| 1271 | if (min[i] != max[i]) |
| 1272 | seq_printf(s, "%s:\t%5d erase blocks, erased min %d, " |
| 1273 | "max %d times\n", |
| 1274 | name[i], count[i], min[i], max[i]); |
| 1275 | else |
| 1276 | seq_printf(s, "%s:\t%5d erase blocks, all erased %d " |
| 1277 | "times\n", name[i], count[i], min[i]); |
| 1278 | } |
| 1279 | |
| 1280 | if (bb_cnt) |
| 1281 | seq_printf(s, "bad:\t%5u erase blocks\n", bb_cnt); |
| 1282 | |
| 1283 | if (cw) |
| 1284 | seq_printf(s, "current erase block: %u pages used, %u free, " |
| 1285 | "erased %u times\n", |
| 1286 | cwp, d->pages_per_eblk - cwp, cwecount); |
| 1287 | |
| 1288 | seq_printf(s, "total erasures: %lu\n", sum); |
| 1289 | |
Samarth Parikh | 6f3c0f1 | 2014-07-16 16:14:37 +0530 | [diff] [blame] | 1290 | seq_puts(s, "\n"); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1291 | |
| 1292 | seq_printf(s, "mtdswap_readsect count: %llu\n", d->sect_read_count); |
| 1293 | seq_printf(s, "mtdswap_writesect count: %llu\n", d->sect_write_count); |
| 1294 | seq_printf(s, "mtdswap_discard count: %llu\n", d->discard_count); |
| 1295 | seq_printf(s, "mtd read count: %llu\n", d->mtd_read_count); |
| 1296 | seq_printf(s, "mtd write count: %llu\n", d->mtd_write_count); |
| 1297 | seq_printf(s, "discarded pages count: %llu\n", d->discard_page_count); |
| 1298 | |
Samarth Parikh | 6f3c0f1 | 2014-07-16 16:14:37 +0530 | [diff] [blame] | 1299 | seq_puts(s, "\n"); |
David Woodhouse | 89d8d32 | 2011-03-11 15:17:41 +0000 | [diff] [blame] | 1300 | seq_printf(s, "total pages: %u\n", pages); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1301 | seq_printf(s, "pages mapped: %u\n", mapped); |
| 1302 | |
| 1303 | return 0; |
| 1304 | } |
| 1305 | |
| 1306 | static int mtdswap_open(struct inode *inode, struct file *file) |
| 1307 | { |
| 1308 | return single_open(file, mtdswap_show, inode->i_private); |
| 1309 | } |
| 1310 | |
| 1311 | static const struct file_operations mtdswap_fops = { |
| 1312 | .open = mtdswap_open, |
| 1313 | .read = seq_read, |
| 1314 | .llseek = seq_lseek, |
| 1315 | .release = single_release, |
| 1316 | }; |
| 1317 | |
| 1318 | static int mtdswap_add_debugfs(struct mtdswap_dev *d) |
| 1319 | { |
| 1320 | struct gendisk *gd = d->mbd_dev->disk; |
| 1321 | struct device *dev = disk_to_dev(gd); |
| 1322 | |
| 1323 | struct dentry *root; |
| 1324 | struct dentry *dent; |
| 1325 | |
| 1326 | root = debugfs_create_dir(gd->disk_name, NULL); |
| 1327 | if (IS_ERR(root)) |
| 1328 | return 0; |
| 1329 | |
| 1330 | if (!root) { |
| 1331 | dev_err(dev, "failed to initialize debugfs\n"); |
| 1332 | return -1; |
| 1333 | } |
| 1334 | |
| 1335 | d->debugfs_root = root; |
| 1336 | |
| 1337 | dent = debugfs_create_file("stats", S_IRUSR, root, d, |
| 1338 | &mtdswap_fops); |
| 1339 | if (!dent) { |
| 1340 | dev_err(d->dev, "debugfs_create_file failed\n"); |
| 1341 | debugfs_remove_recursive(root); |
| 1342 | d->debugfs_root = NULL; |
| 1343 | return -1; |
| 1344 | } |
| 1345 | |
| 1346 | return 0; |
| 1347 | } |
| 1348 | |
| 1349 | static int mtdswap_init(struct mtdswap_dev *d, unsigned int eblocks, |
| 1350 | unsigned int spare_cnt) |
| 1351 | { |
| 1352 | struct mtd_info *mtd = d->mbd_dev->mtd; |
| 1353 | unsigned int i, eblk_bytes, pages, blocks; |
| 1354 | int ret = -ENOMEM; |
| 1355 | |
| 1356 | d->mtd = mtd; |
| 1357 | d->eblks = eblocks; |
| 1358 | d->spare_eblks = spare_cnt; |
| 1359 | d->pages_per_eblk = mtd->erasesize >> PAGE_SHIFT; |
| 1360 | |
| 1361 | pages = d->mbd_dev->size; |
| 1362 | blocks = eblocks * d->pages_per_eblk; |
| 1363 | |
| 1364 | for (i = 0; i < MTDSWAP_TREE_CNT; i++) |
| 1365 | d->trees[i].root = RB_ROOT; |
| 1366 | |
| 1367 | d->page_data = vmalloc(sizeof(int)*pages); |
| 1368 | if (!d->page_data) |
| 1369 | goto page_data_fail; |
| 1370 | |
| 1371 | d->revmap = vmalloc(sizeof(int)*blocks); |
| 1372 | if (!d->revmap) |
| 1373 | goto revmap_fail; |
| 1374 | |
| 1375 | eblk_bytes = sizeof(struct swap_eb)*d->eblks; |
Joe Perches | 1712cde | 2011-05-28 10:36:29 -0700 | [diff] [blame] | 1376 | d->eb_data = vzalloc(eblk_bytes); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1377 | if (!d->eb_data) |
| 1378 | goto eb_data_fail; |
| 1379 | |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1380 | for (i = 0; i < pages; i++) |
| 1381 | d->page_data[i] = BLOCK_UNDEF; |
| 1382 | |
| 1383 | for (i = 0; i < blocks; i++) |
| 1384 | d->revmap[i] = PAGE_UNDEF; |
| 1385 | |
| 1386 | d->page_buf = kmalloc(PAGE_SIZE, GFP_KERNEL); |
| 1387 | if (!d->page_buf) |
| 1388 | goto page_buf_fail; |
| 1389 | |
Boris BREZILLON | f5b8aa7 | 2016-03-07 10:46:51 +0100 | [diff] [blame] | 1390 | d->oob_buf = kmalloc(2 * mtd->oobavail, GFP_KERNEL); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1391 | if (!d->oob_buf) |
| 1392 | goto oob_buf_fail; |
| 1393 | |
| 1394 | mtdswap_scan_eblks(d); |
| 1395 | |
| 1396 | return 0; |
| 1397 | |
| 1398 | oob_buf_fail: |
| 1399 | kfree(d->page_buf); |
| 1400 | page_buf_fail: |
| 1401 | vfree(d->eb_data); |
| 1402 | eb_data_fail: |
| 1403 | vfree(d->revmap); |
| 1404 | revmap_fail: |
| 1405 | vfree(d->page_data); |
| 1406 | page_data_fail: |
| 1407 | printk(KERN_ERR "%s: init failed (%d)\n", MTDSWAP_PREFIX, ret); |
| 1408 | return ret; |
| 1409 | } |
| 1410 | |
| 1411 | static void mtdswap_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) |
| 1412 | { |
| 1413 | struct mtdswap_dev *d; |
| 1414 | struct mtd_blktrans_dev *mbd_dev; |
| 1415 | char *parts; |
| 1416 | char *this_opt; |
| 1417 | unsigned long part; |
| 1418 | unsigned int eblocks, eavailable, bad_blocks, spare_cnt; |
| 1419 | uint64_t swap_size, use_size, size_limit; |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1420 | int ret; |
| 1421 | |
| 1422 | parts = &partitions[0]; |
| 1423 | if (!*parts) |
| 1424 | return; |
| 1425 | |
| 1426 | while ((this_opt = strsep(&parts, ",")) != NULL) { |
Jingoo Han | 3156231 | 2013-07-19 15:54:11 +0900 | [diff] [blame] | 1427 | if (kstrtoul(this_opt, 0, &part) < 0) |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1428 | return; |
| 1429 | |
| 1430 | if (mtd->index == part) |
| 1431 | break; |
| 1432 | } |
| 1433 | |
| 1434 | if (mtd->index != part) |
| 1435 | return; |
| 1436 | |
| 1437 | if (mtd->erasesize < PAGE_SIZE || mtd->erasesize % PAGE_SIZE) { |
| 1438 | printk(KERN_ERR "%s: Erase size %u not multiple of PAGE_SIZE " |
| 1439 | "%lu\n", MTDSWAP_PREFIX, mtd->erasesize, PAGE_SIZE); |
| 1440 | return; |
| 1441 | } |
| 1442 | |
| 1443 | if (PAGE_SIZE % mtd->writesize || mtd->writesize > PAGE_SIZE) { |
| 1444 | printk(KERN_ERR "%s: PAGE_SIZE %lu not multiple of write size" |
| 1445 | " %u\n", MTDSWAP_PREFIX, PAGE_SIZE, mtd->writesize); |
| 1446 | return; |
| 1447 | } |
| 1448 | |
Boris BREZILLON | f5b8aa7 | 2016-03-07 10:46:51 +0100 | [diff] [blame] | 1449 | if (!mtd->oobsize || mtd->oobavail < MTDSWAP_OOBSIZE) { |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1450 | printk(KERN_ERR "%s: Not enough free bytes in OOB, " |
Randy Dunlap | 2130ad3 | 2011-03-29 12:35:23 -0700 | [diff] [blame] | 1451 | "%d available, %zu needed.\n", |
Boris BREZILLON | f5b8aa7 | 2016-03-07 10:46:51 +0100 | [diff] [blame] | 1452 | MTDSWAP_PREFIX, mtd->oobavail, MTDSWAP_OOBSIZE); |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1453 | return; |
| 1454 | } |
| 1455 | |
| 1456 | if (spare_eblocks > 100) |
| 1457 | spare_eblocks = 100; |
| 1458 | |
| 1459 | use_size = mtd->size; |
| 1460 | size_limit = (uint64_t) BLOCK_MAX * PAGE_SIZE; |
| 1461 | |
| 1462 | if (mtd->size > size_limit) { |
| 1463 | printk(KERN_WARNING "%s: Device too large. Limiting size to " |
| 1464 | "%llu bytes\n", MTDSWAP_PREFIX, size_limit); |
| 1465 | use_size = size_limit; |
| 1466 | } |
| 1467 | |
| 1468 | eblocks = mtd_div_by_eb(use_size, mtd); |
Brian Norris | 8c3f3f1 | 2014-07-21 19:07:02 -0700 | [diff] [blame] | 1469 | use_size = (uint64_t)eblocks * mtd->erasesize; |
Jarkko Lavinen | a321590 | 2011-02-14 16:16:11 +0200 | [diff] [blame] | 1470 | bad_blocks = mtdswap_badblocks(mtd, use_size); |
| 1471 | eavailable = eblocks - bad_blocks; |
| 1472 | |
| 1473 | if (eavailable < MIN_ERASE_BLOCKS) { |
| 1474 | printk(KERN_ERR "%s: Not enough erase blocks. %u available, " |
| 1475 | "%d needed\n", MTDSWAP_PREFIX, eavailable, |
| 1476 | MIN_ERASE_BLOCKS); |
| 1477 | return; |
| 1478 | } |
| 1479 | |
| 1480 | spare_cnt = div_u64((uint64_t)eavailable * spare_eblocks, 100); |
| 1481 | |
| 1482 | if (spare_cnt < MIN_SPARE_EBLOCKS) |
| 1483 | spare_cnt = MIN_SPARE_EBLOCKS; |
| 1484 | |
| 1485 | if (spare_cnt > eavailable - 1) |
| 1486 | spare_cnt = eavailable - 1; |
| 1487 | |
| 1488 | swap_size = (uint64_t)(eavailable - spare_cnt) * mtd->erasesize + |
| 1489 | (header ? PAGE_SIZE : 0); |
| 1490 | |
| 1491 | printk(KERN_INFO "%s: Enabling MTD swap on device %lu, size %llu KB, " |
| 1492 | "%u spare, %u bad blocks\n", |
| 1493 | MTDSWAP_PREFIX, part, swap_size / 1024, spare_cnt, bad_blocks); |
| 1494 | |
| 1495 | d = kzalloc(sizeof(struct mtdswap_dev), GFP_KERNEL); |
| 1496 | if (!d) |
| 1497 | return; |
| 1498 | |
| 1499 | mbd_dev = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL); |
| 1500 | if (!mbd_dev) { |
| 1501 | kfree(d); |
| 1502 | return; |
| 1503 | } |
| 1504 | |
| 1505 | d->mbd_dev = mbd_dev; |
| 1506 | mbd_dev->priv = d; |
| 1507 | |
| 1508 | mbd_dev->mtd = mtd; |
| 1509 | mbd_dev->devnum = mtd->index; |
| 1510 | mbd_dev->size = swap_size >> PAGE_SHIFT; |
| 1511 | mbd_dev->tr = tr; |
| 1512 | |
| 1513 | if (!(mtd->flags & MTD_WRITEABLE)) |
| 1514 | mbd_dev->readonly = 1; |
| 1515 | |
| 1516 | if (mtdswap_init(d, eblocks, spare_cnt) < 0) |
| 1517 | goto init_failed; |
| 1518 | |
| 1519 | if (add_mtd_blktrans_dev(mbd_dev) < 0) |
| 1520 | goto cleanup; |
| 1521 | |
| 1522 | d->dev = disk_to_dev(mbd_dev->disk); |
| 1523 | |
| 1524 | ret = mtdswap_add_debugfs(d); |
| 1525 | if (ret < 0) |
| 1526 | goto debugfs_failed; |
| 1527 | |
| 1528 | return; |
| 1529 | |
| 1530 | debugfs_failed: |
| 1531 | del_mtd_blktrans_dev(mbd_dev); |
| 1532 | |
| 1533 | cleanup: |
| 1534 | mtdswap_cleanup(d); |
| 1535 | |
| 1536 | init_failed: |
| 1537 | kfree(mbd_dev); |
| 1538 | kfree(d); |
| 1539 | } |
| 1540 | |
| 1541 | static void mtdswap_remove_dev(struct mtd_blktrans_dev *dev) |
| 1542 | { |
| 1543 | struct mtdswap_dev *d = MTDSWAP_MBD_TO_MTDSWAP(dev); |
| 1544 | |
| 1545 | debugfs_remove_recursive(d->debugfs_root); |
| 1546 | del_mtd_blktrans_dev(dev); |
| 1547 | mtdswap_cleanup(d); |
| 1548 | kfree(d); |
| 1549 | } |
| 1550 | |
| 1551 | static struct mtd_blktrans_ops mtdswap_ops = { |
| 1552 | .name = "mtdswap", |
| 1553 | .major = 0, |
| 1554 | .part_bits = 0, |
| 1555 | .blksize = PAGE_SIZE, |
| 1556 | .flush = mtdswap_flush, |
| 1557 | .readsect = mtdswap_readsect, |
| 1558 | .writesect = mtdswap_writesect, |
| 1559 | .discard = mtdswap_discard, |
| 1560 | .background = mtdswap_background, |
| 1561 | .add_mtd = mtdswap_add_mtd, |
| 1562 | .remove_dev = mtdswap_remove_dev, |
| 1563 | .owner = THIS_MODULE, |
| 1564 | }; |
| 1565 | |
| 1566 | static int __init mtdswap_modinit(void) |
| 1567 | { |
| 1568 | return register_mtd_blktrans(&mtdswap_ops); |
| 1569 | } |
| 1570 | |
| 1571 | static void __exit mtdswap_modexit(void) |
| 1572 | { |
| 1573 | deregister_mtd_blktrans(&mtdswap_ops); |
| 1574 | } |
| 1575 | |
| 1576 | module_init(mtdswap_modinit); |
| 1577 | module_exit(mtdswap_modexit); |
| 1578 | |
| 1579 | |
| 1580 | MODULE_LICENSE("GPL"); |
| 1581 | MODULE_AUTHOR("Jarkko Lavinen <jarkko.lavinen@nokia.com>"); |
| 1582 | MODULE_DESCRIPTION("Block device access to an MTD suitable for using as " |
| 1583 | "swap space"); |