Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * JFFS -- Journaling Flash File System, Linux implementation. |
| 3 | * |
| 4 | * Copyright (C) 1999, 2000 Axis Communications, Inc. |
| 5 | * |
| 6 | * Created by Finn Hakansson <finn@axis.com>. |
| 7 | * |
| 8 | * This is free software; you can redistribute it and/or modify it |
| 9 | * under the terms of the GNU General Public License as published by |
| 10 | * the Free Software Foundation; either version 2 of the License, or |
| 11 | * (at your option) any later version. |
| 12 | * |
| 13 | * $Id: intrep.c,v 1.102 2001/09/23 23:28:36 dwmw2 Exp $ |
| 14 | * |
| 15 | * Ported to Linux 2.3.x and MTD: |
| 16 | * Copyright (C) 2000 Alexander Larsson (alex@cendio.se), Cendio Systems AB |
| 17 | * |
| 18 | */ |
| 19 | |
| 20 | /* This file contains the code for the internal structure of the |
| 21 | Journaling Flash File System, JFFS. */ |
| 22 | |
| 23 | /* |
| 24 | * Todo list: |
| 25 | * |
| 26 | * memcpy_to_flash() and memcpy_from_flash() functions. |
| 27 | * |
| 28 | * Implementation of hard links. |
| 29 | * |
| 30 | * Organize the source code in a better way. Against the VFS we could |
| 31 | * have jffs_ext.c, and against the block device jffs_int.c. |
| 32 | * A better file-internal organization too. |
| 33 | * |
| 34 | * A better checksum algorithm. |
| 35 | * |
| 36 | * Consider endianness stuff. ntohl() etc. |
| 37 | * |
| 38 | * Are we handling the atime, mtime, ctime members of the inode right? |
| 39 | * |
| 40 | * Remove some duplicated code. Take a look at jffs_write_node() and |
| 41 | * jffs_rewrite_data() for instance. |
| 42 | * |
| 43 | * Implement more meaning of the nlink member in various data structures. |
| 44 | * nlink could be used in conjunction with hard links for instance. |
| 45 | * |
| 46 | * Better memory management. Allocate data structures in larger chunks |
| 47 | * if possible. |
| 48 | * |
| 49 | * If too much meta data is stored, a garbage collect should be issued. |
| 50 | * We have experienced problems with too much meta data with for instance |
| 51 | * log files. |
| 52 | * |
| 53 | * Improve the calls to jffs_ioctl(). We would like to retrieve more |
| 54 | * information to be able to debug (or to supervise) JFFS during run-time. |
| 55 | * |
| 56 | */ |
| 57 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | #include <linux/types.h> |
| 59 | #include <linux/slab.h> |
| 60 | #include <linux/jffs.h> |
| 61 | #include <linux/fs.h> |
| 62 | #include <linux/stat.h> |
| 63 | #include <linux/pagemap.h> |
Ingo Molnar | 1eb0d67 | 2006-03-23 03:00:40 -0800 | [diff] [blame] | 64 | #include <linux/mutex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | #include <asm/byteorder.h> |
| 66 | #include <linux/smp_lock.h> |
| 67 | #include <linux/time.h> |
| 68 | #include <linux/ctype.h> |
| 69 | |
| 70 | #include "intrep.h" |
| 71 | #include "jffs_fm.h" |
| 72 | |
| 73 | long no_jffs_node = 0; |
| 74 | static long no_jffs_file = 0; |
| 75 | #if defined(JFFS_MEMORY_DEBUG) && JFFS_MEMORY_DEBUG |
| 76 | long no_jffs_control = 0; |
| 77 | long no_jffs_raw_inode = 0; |
| 78 | long no_jffs_node_ref = 0; |
| 79 | long no_jffs_fm = 0; |
| 80 | long no_jffs_fmcontrol = 0; |
| 81 | long no_hash = 0; |
| 82 | long no_name = 0; |
| 83 | #endif |
| 84 | |
| 85 | static int jffs_scan_flash(struct jffs_control *c); |
| 86 | static int jffs_update_file(struct jffs_file *f, struct jffs_node *node); |
| 87 | static int jffs_build_file(struct jffs_file *f); |
| 88 | static int jffs_free_file(struct jffs_file *f); |
| 89 | static int jffs_free_node_list(struct jffs_file *f); |
| 90 | static int jffs_garbage_collect_now(struct jffs_control *c); |
| 91 | static int jffs_insert_file_into_hash(struct jffs_file *f); |
| 92 | static int jffs_remove_redundant_nodes(struct jffs_file *f); |
| 93 | |
| 94 | /* Is there enough space on the flash? */ |
| 95 | static inline int JFFS_ENOUGH_SPACE(struct jffs_control *c, __u32 space) |
| 96 | { |
| 97 | struct jffs_fmcontrol *fmc = c->fmc; |
| 98 | |
| 99 | while (1) { |
| 100 | if ((fmc->flash_size - (fmc->used_size + fmc->dirty_size)) |
| 101 | >= fmc->min_free_size + space) { |
| 102 | return 1; |
| 103 | } |
| 104 | if (fmc->dirty_size < fmc->sector_size) |
| 105 | return 0; |
| 106 | |
| 107 | if (jffs_garbage_collect_now(c)) { |
| 108 | D1(printk("JFFS_ENOUGH_SPACE: jffs_garbage_collect_now() failed.\n")); |
| 109 | return 0; |
| 110 | } |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | #if CONFIG_JFFS_FS_VERBOSE > 0 |
| 115 | static __u8 |
| 116 | flash_read_u8(struct mtd_info *mtd, loff_t from) |
| 117 | { |
| 118 | size_t retlen; |
| 119 | __u8 ret; |
| 120 | int res; |
| 121 | |
| 122 | res = MTD_READ(mtd, from, 1, &retlen, &ret); |
| 123 | if (retlen != 1) { |
| 124 | printk("Didn't read a byte in flash_read_u8(). Returned %d\n", res); |
| 125 | return 0; |
| 126 | } |
| 127 | |
| 128 | return ret; |
| 129 | } |
| 130 | |
| 131 | static void |
| 132 | jffs_hexdump(struct mtd_info *mtd, loff_t pos, int size) |
| 133 | { |
| 134 | char line[16]; |
| 135 | int j = 0; |
| 136 | |
| 137 | while (size > 0) { |
| 138 | int i; |
| 139 | |
| 140 | printk("%ld:", (long) pos); |
| 141 | for (j = 0; j < 16; j++) { |
| 142 | line[j] = flash_read_u8(mtd, pos++); |
| 143 | } |
| 144 | for (i = 0; i < j; i++) { |
| 145 | if (!(i & 1)) { |
| 146 | printk(" %.2x", line[i] & 0xff); |
| 147 | } |
| 148 | else { |
| 149 | printk("%.2x", line[i] & 0xff); |
| 150 | } |
| 151 | } |
| 152 | |
| 153 | /* Print empty space */ |
| 154 | for (; i < 16; i++) { |
| 155 | if (!(i & 1)) { |
| 156 | printk(" "); |
| 157 | } |
| 158 | else { |
| 159 | printk(" "); |
| 160 | } |
| 161 | } |
| 162 | printk(" "); |
| 163 | |
| 164 | for (i = 0; i < j; i++) { |
| 165 | if (isgraph(line[i])) { |
| 166 | printk("%c", line[i]); |
| 167 | } |
| 168 | else { |
| 169 | printk("."); |
| 170 | } |
| 171 | } |
| 172 | printk("\n"); |
| 173 | size -= 16; |
| 174 | } |
| 175 | } |
| 176 | |
Adrian Bunk | 94c9eca | 2005-06-25 14:59:06 -0700 | [diff] [blame] | 177 | /* Print the contents of a node. */ |
| 178 | static void |
| 179 | jffs_print_node(struct jffs_node *n) |
| 180 | { |
| 181 | D(printk("jffs_node: 0x%p\n", n)); |
| 182 | D(printk("{\n")); |
| 183 | D(printk(" 0x%08x, /* version */\n", n->version)); |
| 184 | D(printk(" 0x%08x, /* data_offset */\n", n->data_offset)); |
| 185 | D(printk(" 0x%08x, /* data_size */\n", n->data_size)); |
| 186 | D(printk(" 0x%08x, /* removed_size */\n", n->removed_size)); |
| 187 | D(printk(" 0x%08x, /* fm_offset */\n", n->fm_offset)); |
| 188 | D(printk(" 0x%02x, /* name_size */\n", n->name_size)); |
| 189 | D(printk(" 0x%p, /* fm, fm->offset: %u */\n", |
| 190 | n->fm, (n->fm ? n->fm->offset : 0))); |
| 191 | D(printk(" 0x%p, /* version_prev */\n", n->version_prev)); |
| 192 | D(printk(" 0x%p, /* version_next */\n", n->version_next)); |
| 193 | D(printk(" 0x%p, /* range_prev */\n", n->range_prev)); |
| 194 | D(printk(" 0x%p, /* range_next */\n", n->range_next)); |
| 195 | D(printk("}\n")); |
| 196 | } |
| 197 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | #endif |
| 199 | |
Adrian Bunk | 94c9eca | 2005-06-25 14:59:06 -0700 | [diff] [blame] | 200 | /* Print the contents of a raw inode. */ |
| 201 | static void |
| 202 | jffs_print_raw_inode(struct jffs_raw_inode *raw_inode) |
| 203 | { |
| 204 | D(printk("jffs_raw_inode: inode number: %u\n", raw_inode->ino)); |
| 205 | D(printk("{\n")); |
| 206 | D(printk(" 0x%08x, /* magic */\n", raw_inode->magic)); |
| 207 | D(printk(" 0x%08x, /* ino */\n", raw_inode->ino)); |
| 208 | D(printk(" 0x%08x, /* pino */\n", raw_inode->pino)); |
| 209 | D(printk(" 0x%08x, /* version */\n", raw_inode->version)); |
| 210 | D(printk(" 0x%08x, /* mode */\n", raw_inode->mode)); |
| 211 | D(printk(" 0x%04x, /* uid */\n", raw_inode->uid)); |
| 212 | D(printk(" 0x%04x, /* gid */\n", raw_inode->gid)); |
| 213 | D(printk(" 0x%08x, /* atime */\n", raw_inode->atime)); |
| 214 | D(printk(" 0x%08x, /* mtime */\n", raw_inode->mtime)); |
| 215 | D(printk(" 0x%08x, /* ctime */\n", raw_inode->ctime)); |
| 216 | D(printk(" 0x%08x, /* offset */\n", raw_inode->offset)); |
| 217 | D(printk(" 0x%08x, /* dsize */\n", raw_inode->dsize)); |
| 218 | D(printk(" 0x%08x, /* rsize */\n", raw_inode->rsize)); |
| 219 | D(printk(" 0x%02x, /* nsize */\n", raw_inode->nsize)); |
| 220 | D(printk(" 0x%02x, /* nlink */\n", raw_inode->nlink)); |
| 221 | D(printk(" 0x%02x, /* spare */\n", |
| 222 | raw_inode->spare)); |
| 223 | D(printk(" %u, /* rename */\n", |
| 224 | raw_inode->rename)); |
| 225 | D(printk(" %u, /* deleted */\n", |
| 226 | raw_inode->deleted)); |
| 227 | D(printk(" 0x%02x, /* accurate */\n", |
| 228 | raw_inode->accurate)); |
| 229 | D(printk(" 0x%08x, /* dchksum */\n", raw_inode->dchksum)); |
| 230 | D(printk(" 0x%04x, /* nchksum */\n", raw_inode->nchksum)); |
| 231 | D(printk(" 0x%04x, /* chksum */\n", raw_inode->chksum)); |
| 232 | D(printk("}\n")); |
| 233 | } |
| 234 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | #define flash_safe_acquire(arg) |
| 236 | #define flash_safe_release(arg) |
| 237 | |
| 238 | |
| 239 | static int |
| 240 | flash_safe_read(struct mtd_info *mtd, loff_t from, |
| 241 | u_char *buf, size_t count) |
| 242 | { |
| 243 | size_t retlen; |
| 244 | int res; |
| 245 | |
| 246 | D3(printk(KERN_NOTICE "flash_safe_read(%p, %08x, %p, %08x)\n", |
| 247 | mtd, (unsigned int) from, buf, count)); |
| 248 | |
Thomas Gleixner | f4a43cf | 2006-05-28 11:01:53 +0200 | [diff] [blame] | 249 | res = mtd->read(mtd, from, count, &retlen, buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | if (retlen != count) { |
| 251 | panic("Didn't read all bytes in flash_safe_read(). Returned %d\n", res); |
| 252 | } |
| 253 | return res?res:retlen; |
| 254 | } |
| 255 | |
| 256 | |
| 257 | static __u32 |
| 258 | flash_read_u32(struct mtd_info *mtd, loff_t from) |
| 259 | { |
| 260 | size_t retlen; |
| 261 | __u32 ret; |
| 262 | int res; |
| 263 | |
Thomas Gleixner | f4a43cf | 2006-05-28 11:01:53 +0200 | [diff] [blame] | 264 | res = mtd->read(mtd, from, 4, &retlen, (unsigned char *)&ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 265 | if (retlen != 4) { |
| 266 | printk("Didn't read all bytes in flash_read_u32(). Returned %d\n", res); |
| 267 | return 0; |
| 268 | } |
| 269 | |
| 270 | return ret; |
| 271 | } |
| 272 | |
| 273 | |
| 274 | static int |
| 275 | flash_safe_write(struct mtd_info *mtd, loff_t to, |
| 276 | const u_char *buf, size_t count) |
| 277 | { |
| 278 | size_t retlen; |
| 279 | int res; |
| 280 | |
| 281 | D3(printk(KERN_NOTICE "flash_safe_write(%p, %08x, %p, %08x)\n", |
| 282 | mtd, (unsigned int) to, buf, count)); |
| 283 | |
Thomas Gleixner | f4a43cf | 2006-05-28 11:01:53 +0200 | [diff] [blame] | 284 | res = mtd->write(mtd, to, count, &retlen, buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 285 | if (retlen != count) { |
| 286 | printk("Didn't write all bytes in flash_safe_write(). Returned %d\n", res); |
| 287 | } |
| 288 | return res?res:retlen; |
| 289 | } |
| 290 | |
| 291 | |
| 292 | static int |
| 293 | flash_safe_writev(struct mtd_info *mtd, const struct kvec *vecs, |
| 294 | unsigned long iovec_cnt, loff_t to) |
| 295 | { |
| 296 | size_t retlen, retlen_a; |
| 297 | int i; |
| 298 | int res; |
| 299 | |
| 300 | D3(printk(KERN_NOTICE "flash_safe_writev(%p, %08x, %p)\n", |
| 301 | mtd, (unsigned int) to, vecs)); |
Thomas Gleixner | f4a43cf | 2006-05-28 11:01:53 +0200 | [diff] [blame] | 302 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | if (mtd->writev) { |
Thomas Gleixner | f4a43cf | 2006-05-28 11:01:53 +0200 | [diff] [blame] | 304 | res = mtd->writev(mtd, vecs, iovec_cnt, to, &retlen); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | return res ? res : retlen; |
| 306 | } |
| 307 | /* Not implemented writev. Repeatedly use write - on the not so |
| 308 | unreasonable assumption that the mtd driver doesn't care how |
| 309 | many write cycles we use. */ |
| 310 | res=0; |
| 311 | retlen=0; |
| 312 | |
| 313 | for (i=0; !res && i<iovec_cnt; i++) { |
Thomas Gleixner | f4a43cf | 2006-05-28 11:01:53 +0200 | [diff] [blame] | 314 | res = mtd->write(mtd, to, vecs[i].iov_len, &retlen_a, |
| 315 | vecs[i].iov_base); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | if (retlen_a != vecs[i].iov_len) { |
| 317 | printk("Didn't write all bytes in flash_safe_writev(). Returned %d\n", res); |
| 318 | if (i != iovec_cnt-1) |
| 319 | return -EIO; |
| 320 | } |
| 321 | /* If res is non-zero, retlen_a is undefined, but we don't |
| 322 | care because in that case it's not going to be |
| 323 | returned anyway. |
| 324 | */ |
| 325 | to += retlen_a; |
| 326 | retlen += retlen_a; |
| 327 | } |
| 328 | return res?res:retlen; |
| 329 | } |
| 330 | |
| 331 | |
| 332 | static int |
| 333 | flash_memset(struct mtd_info *mtd, loff_t to, |
| 334 | const u_char c, size_t size) |
| 335 | { |
| 336 | static unsigned char pattern[64]; |
| 337 | int i; |
| 338 | |
| 339 | /* fill up pattern */ |
| 340 | |
| 341 | for(i = 0; i < 64; i++) |
| 342 | pattern[i] = c; |
| 343 | |
| 344 | /* write as many 64-byte chunks as we can */ |
| 345 | |
| 346 | while (size >= 64) { |
| 347 | flash_safe_write(mtd, to, pattern, 64); |
| 348 | size -= 64; |
| 349 | to += 64; |
| 350 | } |
| 351 | |
| 352 | /* and the rest */ |
| 353 | |
| 354 | if(size) |
| 355 | flash_safe_write(mtd, to, pattern, size); |
| 356 | |
| 357 | return size; |
| 358 | } |
| 359 | |
| 360 | |
| 361 | static void |
| 362 | intrep_erase_callback(struct erase_info *done) |
| 363 | { |
| 364 | wait_queue_head_t *wait_q; |
| 365 | |
| 366 | wait_q = (wait_queue_head_t *)done->priv; |
| 367 | |
| 368 | wake_up(wait_q); |
| 369 | } |
| 370 | |
| 371 | |
| 372 | static int |
| 373 | flash_erase_region(struct mtd_info *mtd, loff_t start, |
| 374 | size_t size) |
| 375 | { |
| 376 | struct erase_info *erase; |
| 377 | DECLARE_WAITQUEUE(wait, current); |
| 378 | wait_queue_head_t wait_q; |
| 379 | |
| 380 | erase = kmalloc(sizeof(struct erase_info), GFP_KERNEL); |
| 381 | if (!erase) |
| 382 | return -ENOMEM; |
| 383 | |
| 384 | init_waitqueue_head(&wait_q); |
| 385 | |
| 386 | erase->mtd = mtd; |
| 387 | erase->callback = intrep_erase_callback; |
| 388 | erase->addr = start; |
| 389 | erase->len = size; |
| 390 | erase->priv = (u_long)&wait_q; |
| 391 | |
| 392 | /* FIXME: Use TASK_INTERRUPTIBLE and deal with being interrupted */ |
| 393 | set_current_state(TASK_UNINTERRUPTIBLE); |
| 394 | add_wait_queue(&wait_q, &wait); |
| 395 | |
Thomas Gleixner | f4a43cf | 2006-05-28 11:01:53 +0200 | [diff] [blame] | 396 | if (mtd->erase(mtd, erase) < 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | set_current_state(TASK_RUNNING); |
| 398 | remove_wait_queue(&wait_q, &wait); |
| 399 | kfree(erase); |
| 400 | |
| 401 | printk(KERN_WARNING "flash: erase of region [0x%lx, 0x%lx] " |
| 402 | "totally failed\n", (long)start, (long)start + size); |
| 403 | |
| 404 | return -1; |
| 405 | } |
| 406 | |
| 407 | schedule(); /* Wait for flash to finish. */ |
| 408 | remove_wait_queue(&wait_q, &wait); |
| 409 | |
| 410 | kfree(erase); |
| 411 | |
| 412 | return 0; |
| 413 | } |
| 414 | |
| 415 | /* This routine calculates checksums in JFFS. */ |
| 416 | static __u32 |
| 417 | jffs_checksum(const void *data, int size) |
| 418 | { |
| 419 | __u32 sum = 0; |
| 420 | __u8 *ptr = (__u8 *)data; |
| 421 | while (size-- > 0) { |
| 422 | sum += *ptr++; |
| 423 | } |
| 424 | D3(printk(", result: 0x%08x\n", sum)); |
| 425 | return sum; |
| 426 | } |
| 427 | |
| 428 | |
| 429 | static int |
| 430 | jffs_checksum_flash(struct mtd_info *mtd, loff_t start, int size, __u32 *result) |
| 431 | { |
| 432 | __u32 sum = 0; |
| 433 | loff_t ptr = start; |
| 434 | __u8 *read_buf; |
| 435 | int i, length; |
| 436 | |
| 437 | /* Allocate read buffer */ |
| 438 | read_buf = (__u8 *) kmalloc (sizeof(__u8) * 4096, GFP_KERNEL); |
| 439 | if (!read_buf) { |
| 440 | printk(KERN_NOTICE "kmalloc failed in jffs_checksum_flash()\n"); |
| 441 | return -ENOMEM; |
| 442 | } |
| 443 | /* Loop until checksum done */ |
| 444 | while (size) { |
| 445 | /* Get amount of data to read */ |
| 446 | if (size < 4096) |
| 447 | length = size; |
| 448 | else |
| 449 | length = 4096; |
| 450 | |
| 451 | /* Perform flash read */ |
| 452 | D3(printk(KERN_NOTICE "jffs_checksum_flash\n")); |
| 453 | flash_safe_read(mtd, ptr, &read_buf[0], length); |
| 454 | |
| 455 | /* Compute checksum */ |
| 456 | for (i=0; i < length ; i++) |
| 457 | sum += read_buf[i]; |
| 458 | |
| 459 | /* Update pointer and size */ |
| 460 | size -= length; |
| 461 | ptr += length; |
| 462 | } |
| 463 | |
| 464 | /* Free read buffer */ |
Jesper Juhl | f99d49a | 2005-11-07 01:01:34 -0800 | [diff] [blame] | 465 | kfree(read_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | |
| 467 | /* Return result */ |
| 468 | D3(printk("checksum result: 0x%08x\n", sum)); |
| 469 | *result = sum; |
| 470 | return 0; |
| 471 | } |
| 472 | |
| 473 | static __inline__ void jffs_fm_write_lock(struct jffs_fmcontrol *fmc) |
| 474 | { |
| 475 | // down(&fmc->wlock); |
| 476 | } |
| 477 | |
| 478 | static __inline__ void jffs_fm_write_unlock(struct jffs_fmcontrol *fmc) |
| 479 | { |
| 480 | // up(&fmc->wlock); |
| 481 | } |
| 482 | |
| 483 | |
| 484 | /* Create and initialize a new struct jffs_file. */ |
| 485 | static struct jffs_file * |
| 486 | jffs_create_file(struct jffs_control *c, |
| 487 | const struct jffs_raw_inode *raw_inode) |
| 488 | { |
| 489 | struct jffs_file *f; |
| 490 | |
Panagiotis Issaris | f52720c | 2006-09-27 01:49:39 -0700 | [diff] [blame] | 491 | if (!(f = kzalloc(sizeof(*f), GFP_KERNEL))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 492 | D(printk("jffs_create_file(): Failed!\n")); |
| 493 | return NULL; |
| 494 | } |
| 495 | no_jffs_file++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 496 | f->ino = raw_inode->ino; |
| 497 | f->pino = raw_inode->pino; |
| 498 | f->nlink = raw_inode->nlink; |
| 499 | f->deleted = raw_inode->deleted; |
| 500 | f->c = c; |
| 501 | |
| 502 | return f; |
| 503 | } |
| 504 | |
| 505 | |
| 506 | /* Build a control block for the file system. */ |
| 507 | static struct jffs_control * |
| 508 | jffs_create_control(struct super_block *sb) |
| 509 | { |
| 510 | struct jffs_control *c; |
| 511 | register int s = sizeof(struct jffs_control); |
| 512 | int i; |
| 513 | D(char *t = 0); |
| 514 | |
| 515 | D2(printk("jffs_create_control()\n")); |
| 516 | |
Panagiotis Issaris | f52720c | 2006-09-27 01:49:39 -0700 | [diff] [blame] | 517 | if (!(c = kmalloc(s, GFP_KERNEL))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | goto fail_control; |
| 519 | } |
| 520 | DJM(no_jffs_control++); |
| 521 | c->root = NULL; |
| 522 | c->gc_task = NULL; |
| 523 | c->hash_len = JFFS_HASH_SIZE; |
| 524 | s = sizeof(struct list_head) * c->hash_len; |
Panagiotis Issaris | f52720c | 2006-09-27 01:49:39 -0700 | [diff] [blame] | 525 | if (!(c->hash = kmalloc(s, GFP_KERNEL))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 526 | goto fail_hash; |
| 527 | } |
| 528 | DJM(no_hash++); |
| 529 | for (i = 0; i < c->hash_len; i++) |
| 530 | INIT_LIST_HEAD(&c->hash[i]); |
| 531 | if (!(c->fmc = jffs_build_begin(c, MINOR(sb->s_dev)))) { |
| 532 | goto fail_fminit; |
| 533 | } |
| 534 | c->next_ino = JFFS_MIN_INO + 1; |
| 535 | c->delete_list = (struct jffs_delete_list *) 0; |
| 536 | return c; |
| 537 | |
| 538 | fail_fminit: |
| 539 | D(t = "c->fmc"); |
| 540 | fail_hash: |
| 541 | kfree(c); |
| 542 | DJM(no_jffs_control--); |
| 543 | D(t = t ? t : "c->hash"); |
| 544 | fail_control: |
| 545 | D(t = t ? t : "control"); |
| 546 | D(printk("jffs_create_control(): Allocation failed: (%s)\n", t)); |
| 547 | return (struct jffs_control *)0; |
| 548 | } |
| 549 | |
| 550 | |
| 551 | /* Clean up all data structures associated with the file system. */ |
| 552 | void |
| 553 | jffs_cleanup_control(struct jffs_control *c) |
| 554 | { |
| 555 | D2(printk("jffs_cleanup_control()\n")); |
| 556 | |
| 557 | if (!c) { |
| 558 | D(printk("jffs_cleanup_control(): c == NULL !!!\n")); |
| 559 | return; |
| 560 | } |
| 561 | |
| 562 | while (c->delete_list) { |
| 563 | struct jffs_delete_list *delete_list_element; |
| 564 | delete_list_element = c->delete_list; |
| 565 | c->delete_list = c->delete_list->next; |
| 566 | kfree(delete_list_element); |
| 567 | } |
| 568 | |
| 569 | /* Free all files and nodes. */ |
| 570 | if (c->hash) { |
| 571 | jffs_foreach_file(c, jffs_free_node_list); |
| 572 | jffs_foreach_file(c, jffs_free_file); |
| 573 | kfree(c->hash); |
| 574 | DJM(no_hash--); |
| 575 | } |
| 576 | jffs_cleanup_fmcontrol(c->fmc); |
| 577 | kfree(c); |
| 578 | DJM(no_jffs_control--); |
| 579 | D3(printk("jffs_cleanup_control(): Leaving...\n")); |
| 580 | } |
| 581 | |
| 582 | |
| 583 | /* This function adds a virtual root node to the in-RAM representation. |
| 584 | Called by jffs_build_fs(). */ |
| 585 | static int |
| 586 | jffs_add_virtual_root(struct jffs_control *c) |
| 587 | { |
| 588 | struct jffs_file *root; |
| 589 | struct jffs_node *node; |
| 590 | |
| 591 | D2(printk("jffs_add_virtual_root(): " |
| 592 | "Creating a virtual root directory.\n")); |
| 593 | |
Panagiotis Issaris | f52720c | 2006-09-27 01:49:39 -0700 | [diff] [blame] | 594 | if (!(root = kmalloc(sizeof(struct jffs_file), GFP_KERNEL))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 595 | return -ENOMEM; |
| 596 | } |
| 597 | no_jffs_file++; |
| 598 | if (!(node = jffs_alloc_node())) { |
| 599 | kfree(root); |
| 600 | no_jffs_file--; |
| 601 | return -ENOMEM; |
| 602 | } |
| 603 | DJM(no_jffs_node++); |
| 604 | memset(node, 0, sizeof(struct jffs_node)); |
| 605 | node->ino = JFFS_MIN_INO; |
| 606 | memset(root, 0, sizeof(struct jffs_file)); |
| 607 | root->ino = JFFS_MIN_INO; |
| 608 | root->mode = S_IFDIR | S_IRWXU | S_IRGRP |
| 609 | | S_IXGRP | S_IROTH | S_IXOTH; |
| 610 | root->atime = root->mtime = root->ctime = get_seconds(); |
| 611 | root->nlink = 1; |
| 612 | root->c = c; |
| 613 | root->version_head = root->version_tail = node; |
| 614 | jffs_insert_file_into_hash(root); |
| 615 | return 0; |
| 616 | } |
| 617 | |
| 618 | |
| 619 | /* This is where the file system is built and initialized. */ |
| 620 | int |
| 621 | jffs_build_fs(struct super_block *sb) |
| 622 | { |
| 623 | struct jffs_control *c; |
| 624 | int err = 0; |
| 625 | |
| 626 | D2(printk("jffs_build_fs()\n")); |
| 627 | |
| 628 | if (!(c = jffs_create_control(sb))) { |
| 629 | return -ENOMEM; |
| 630 | } |
| 631 | c->building_fs = 1; |
| 632 | c->sb = sb; |
| 633 | if ((err = jffs_scan_flash(c)) < 0) { |
| 634 | if(err == -EAGAIN){ |
| 635 | /* scan_flash() wants us to try once more. A flipping |
| 636 | bits sector was detect in the middle of the scan flash. |
| 637 | Clean up old allocated memory before going in. |
| 638 | */ |
| 639 | D1(printk("jffs_build_fs: Cleaning up all control structures," |
| 640 | " reallocating them and trying mount again.\n")); |
| 641 | jffs_cleanup_control(c); |
| 642 | if (!(c = jffs_create_control(sb))) { |
| 643 | return -ENOMEM; |
| 644 | } |
| 645 | c->building_fs = 1; |
| 646 | c->sb = sb; |
| 647 | |
| 648 | if ((err = jffs_scan_flash(c)) < 0) { |
| 649 | goto jffs_build_fs_fail; |
| 650 | } |
| 651 | }else{ |
| 652 | goto jffs_build_fs_fail; |
| 653 | } |
| 654 | } |
| 655 | |
| 656 | /* Add a virtual root node if no one exists. */ |
| 657 | if (!jffs_find_file(c, JFFS_MIN_INO)) { |
| 658 | if ((err = jffs_add_virtual_root(c)) < 0) { |
| 659 | goto jffs_build_fs_fail; |
| 660 | } |
| 661 | } |
| 662 | |
| 663 | while (c->delete_list) { |
| 664 | struct jffs_file *f; |
| 665 | struct jffs_delete_list *delete_list_element; |
| 666 | |
| 667 | if ((f = jffs_find_file(c, c->delete_list->ino))) { |
| 668 | f->deleted = 1; |
| 669 | } |
| 670 | delete_list_element = c->delete_list; |
| 671 | c->delete_list = c->delete_list->next; |
| 672 | kfree(delete_list_element); |
| 673 | } |
| 674 | |
| 675 | /* Remove deleted nodes. */ |
| 676 | if ((err = jffs_foreach_file(c, jffs_possibly_delete_file)) < 0) { |
| 677 | printk(KERN_ERR "JFFS: Failed to remove deleted nodes.\n"); |
| 678 | goto jffs_build_fs_fail; |
| 679 | } |
| 680 | /* Remove redundant nodes. (We are not interested in the |
| 681 | return value in this case.) */ |
| 682 | jffs_foreach_file(c, jffs_remove_redundant_nodes); |
| 683 | /* Try to build a tree from all the nodes. */ |
| 684 | if ((err = jffs_foreach_file(c, jffs_insert_file_into_tree)) < 0) { |
| 685 | printk("JFFS: Failed to build tree.\n"); |
| 686 | goto jffs_build_fs_fail; |
| 687 | } |
| 688 | /* Compute the sizes of all files in the filesystem. Adjust if |
| 689 | necessary. */ |
| 690 | if ((err = jffs_foreach_file(c, jffs_build_file)) < 0) { |
| 691 | printk("JFFS: Failed to build file system.\n"); |
| 692 | goto jffs_build_fs_fail; |
| 693 | } |
| 694 | sb->s_fs_info = (void *)c; |
| 695 | c->building_fs = 0; |
| 696 | |
| 697 | D1(jffs_print_hash_table(c)); |
| 698 | D1(jffs_print_tree(c->root, 0)); |
| 699 | |
| 700 | return 0; |
| 701 | |
| 702 | jffs_build_fs_fail: |
| 703 | jffs_cleanup_control(c); |
| 704 | return err; |
| 705 | } /* jffs_build_fs() */ |
| 706 | |
| 707 | |
| 708 | /* |
| 709 | This checks for sectors that were being erased in their previous |
| 710 | lifetimes and for some reason or the other (power fail etc.), |
| 711 | the erase cycles never completed. |
| 712 | As the flash array would have reverted back to read status, |
| 713 | these sectors are detected by the symptom of the "flipping bits", |
| 714 | i.e. bits being read back differently from the same location in |
| 715 | flash if read multiple times. |
| 716 | The only solution to this is to re-erase the entire |
| 717 | sector. |
| 718 | Unfortunately detecting "flipping bits" is not a simple exercise |
| 719 | as a bit may be read back at 1 or 0 depending on the alignment |
| 720 | of the stars in the universe. |
| 721 | The level of confidence is in direct proportion to the number of |
| 722 | scans done. By power fail testing I (Vipin) have been able to |
| 723 | proove that reading twice is not enough. |
| 724 | Maybe 4 times? Change NUM_REREADS to a higher number if you want |
| 725 | a (even) higher degree of confidence in your mount process. |
| 726 | A higher number would of course slow down your mount. |
| 727 | */ |
| 728 | static int check_partly_erased_sectors(struct jffs_fmcontrol *fmc){ |
| 729 | |
| 730 | #define NUM_REREADS 4 /* see note above */ |
| 731 | #define READ_AHEAD_BYTES 4096 /* must be a multiple of 4, |
| 732 | usually set to kernel page size */ |
| 733 | |
| 734 | __u8 *read_buf1; |
| 735 | __u8 *read_buf2; |
| 736 | |
| 737 | int err = 0; |
| 738 | int retlen; |
| 739 | int i; |
| 740 | int cnt; |
| 741 | __u32 offset; |
| 742 | loff_t pos = 0; |
| 743 | loff_t end = fmc->flash_size; |
| 744 | |
| 745 | |
| 746 | /* Allocate read buffers */ |
| 747 | read_buf1 = (__u8 *) kmalloc (sizeof(__u8) * READ_AHEAD_BYTES, GFP_KERNEL); |
| 748 | if (!read_buf1) |
| 749 | return -ENOMEM; |
| 750 | |
| 751 | read_buf2 = (__u8 *) kmalloc (sizeof(__u8) * READ_AHEAD_BYTES, GFP_KERNEL); |
| 752 | if (!read_buf2) { |
| 753 | kfree(read_buf1); |
| 754 | return -ENOMEM; |
| 755 | } |
| 756 | |
| 757 | CHECK_NEXT: |
| 758 | while(pos < end){ |
| 759 | |
| 760 | D1(printk("check_partly_erased_sector():checking sector which contains" |
| 761 | " offset 0x%x for flipping bits..\n", (__u32)pos)); |
| 762 | |
| 763 | retlen = flash_safe_read(fmc->mtd, pos, |
| 764 | &read_buf1[0], READ_AHEAD_BYTES); |
| 765 | retlen &= ~3; |
| 766 | |
| 767 | for(cnt = 0; cnt < NUM_REREADS; cnt++){ |
| 768 | (void)flash_safe_read(fmc->mtd, pos, |
| 769 | &read_buf2[0], READ_AHEAD_BYTES); |
| 770 | |
| 771 | for (i=0 ; i < retlen ; i+=4) { |
| 772 | /* buffers MUST match, double word for word! */ |
| 773 | if(*((__u32 *) &read_buf1[i]) != |
| 774 | *((__u32 *) &read_buf2[i]) |
| 775 | ){ |
| 776 | /* flipping bits detected, time to erase sector */ |
| 777 | /* This will help us log some statistics etc. */ |
| 778 | D1(printk("Flipping bits detected in re-read round:%i of %i\n", |
| 779 | cnt, NUM_REREADS)); |
| 780 | D1(printk("check_partly_erased_sectors:flipping bits detected" |
| 781 | " @offset:0x%x(0x%x!=0x%x)\n", |
| 782 | (__u32)pos+i, *((__u32 *) &read_buf1[i]), |
| 783 | *((__u32 *) &read_buf2[i]))); |
| 784 | |
| 785 | /* calculate start of present sector */ |
| 786 | offset = (((__u32)pos+i)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size; |
| 787 | |
| 788 | D1(printk("check_partly_erased_sector():erasing sector starting 0x%x.\n", |
| 789 | offset)); |
| 790 | |
| 791 | if (flash_erase_region(fmc->mtd, |
| 792 | offset, fmc->sector_size) < 0) { |
| 793 | printk(KERN_ERR "JFFS: Erase of flash failed. " |
| 794 | "offset = %u, erase_size = %d\n", |
| 795 | offset , fmc->sector_size); |
| 796 | |
| 797 | err = -EIO; |
| 798 | goto returnBack; |
| 799 | |
| 800 | }else{ |
| 801 | D1(printk("JFFS: Erase of flash sector @0x%x successful.\n", |
| 802 | offset)); |
| 803 | /* skip ahead to the next sector */ |
| 804 | pos = (((__u32)pos+i)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size; |
| 805 | pos += fmc->sector_size; |
| 806 | goto CHECK_NEXT; |
| 807 | } |
| 808 | } |
| 809 | } |
| 810 | } |
| 811 | pos += READ_AHEAD_BYTES; |
| 812 | } |
| 813 | |
| 814 | returnBack: |
| 815 | kfree(read_buf1); |
| 816 | kfree(read_buf2); |
| 817 | |
| 818 | D2(printk("check_partly_erased_sector():Done checking all sectors till offset 0x%x for flipping bits.\n", |
| 819 | (__u32)pos)); |
| 820 | |
| 821 | return err; |
| 822 | |
| 823 | }/* end check_partly_erased_sectors() */ |
| 824 | |
| 825 | |
| 826 | |
| 827 | /* Scan the whole flash memory in order to find all nodes in the |
| 828 | file systems. */ |
| 829 | static int |
| 830 | jffs_scan_flash(struct jffs_control *c) |
| 831 | { |
| 832 | char name[JFFS_MAX_NAME_LEN + 2]; |
| 833 | struct jffs_raw_inode raw_inode; |
| 834 | struct jffs_node *node = NULL; |
| 835 | struct jffs_fmcontrol *fmc = c->fmc; |
| 836 | __u32 checksum; |
| 837 | __u8 tmp_accurate; |
| 838 | __u16 tmp_chksum; |
| 839 | __u32 deleted_file; |
| 840 | loff_t pos = 0; |
| 841 | loff_t start; |
| 842 | loff_t test_start; |
| 843 | loff_t end = fmc->flash_size; |
| 844 | __u8 *read_buf; |
| 845 | int i, len, retlen; |
| 846 | __u32 offset; |
| 847 | |
| 848 | __u32 free_chunk_size1; |
| 849 | __u32 free_chunk_size2; |
| 850 | |
| 851 | |
| 852 | #define NUMFREEALLOWED 2 /* 2 chunks of at least erase size space allowed */ |
| 853 | int num_free_space = 0; /* Flag err if more than TWO |
| 854 | free blocks found. This is NOT allowed |
| 855 | by the current jffs design. |
| 856 | */ |
| 857 | int num_free_spc_not_accp = 0; /* For debugging purposed keep count |
| 858 | of how much free space was rejected and |
| 859 | marked dirty |
| 860 | */ |
| 861 | |
| 862 | D1(printk("jffs_scan_flash(): start pos = 0x%lx, end = 0x%lx\n", |
| 863 | (long)pos, (long)end)); |
| 864 | |
| 865 | flash_safe_acquire(fmc->mtd); |
| 866 | |
| 867 | /* |
| 868 | check and make sure that any sector does not suffer |
| 869 | from the "partly erased, bit flipping syndrome" (TM Vipin :) |
| 870 | If so, offending sectors will be erased. |
| 871 | */ |
| 872 | if(check_partly_erased_sectors(fmc) < 0){ |
| 873 | |
| 874 | flash_safe_release(fmc->mtd); |
| 875 | return -EIO; /* bad, bad, bad error. Cannot continue.*/ |
| 876 | } |
| 877 | |
| 878 | /* Allocate read buffer */ |
| 879 | read_buf = (__u8 *) kmalloc (sizeof(__u8) * 4096, GFP_KERNEL); |
| 880 | if (!read_buf) { |
| 881 | flash_safe_release(fmc->mtd); |
| 882 | return -ENOMEM; |
| 883 | } |
| 884 | |
| 885 | /* Start the scan. */ |
| 886 | while (pos < end) { |
| 887 | deleted_file = 0; |
| 888 | |
| 889 | /* Remember the position from where we started this scan. */ |
| 890 | start = pos; |
| 891 | |
| 892 | switch (flash_read_u32(fmc->mtd, pos)) { |
| 893 | case JFFS_EMPTY_BITMASK: |
| 894 | /* We have found 0xffffffff at this position. We have to |
| 895 | scan the rest of the flash till the end or till |
| 896 | something else than 0xffffffff is found. |
| 897 | Keep going till we do not find JFFS_EMPTY_BITMASK |
| 898 | anymore */ |
| 899 | |
| 900 | D1(printk("jffs_scan_flash(): 0xffffffff at pos 0x%lx.\n", |
| 901 | (long)pos)); |
| 902 | |
| 903 | while(pos < end){ |
| 904 | |
| 905 | len = end - pos < 4096 ? end - pos : 4096; |
| 906 | |
| 907 | retlen = flash_safe_read(fmc->mtd, pos, |
| 908 | &read_buf[0], len); |
| 909 | |
| 910 | retlen &= ~3; |
| 911 | |
| 912 | for (i=0 ; i < retlen ; i+=4, pos += 4) { |
| 913 | if(*((__u32 *) &read_buf[i]) != |
| 914 | JFFS_EMPTY_BITMASK) |
| 915 | break; |
| 916 | } |
| 917 | if (i == retlen) |
| 918 | continue; |
| 919 | else |
| 920 | break; |
| 921 | } |
| 922 | |
| 923 | D1(printk("jffs_scan_flash():0xffffffff ended at pos 0x%lx.\n", |
| 924 | (long)pos)); |
| 925 | |
| 926 | /* If some free space ends in the middle of a sector, |
| 927 | treat it as dirty rather than clean. |
| 928 | This is to handle the case where one thread |
| 929 | allocated space for a node, but didn't get to |
| 930 | actually _write_ it before power was lost, leaving |
| 931 | a gap in the log. Shifting all node writes into |
| 932 | a single kernel thread will fix the original problem. |
| 933 | */ |
| 934 | if ((__u32) pos % fmc->sector_size) { |
| 935 | /* If there was free space in previous |
| 936 | sectors, don't mark that dirty too - |
| 937 | only from the beginning of this sector |
| 938 | (or from start) |
| 939 | */ |
| 940 | |
| 941 | test_start = pos & ~(fmc->sector_size-1); /* end of last sector */ |
| 942 | |
| 943 | if (start < test_start) { |
| 944 | |
| 945 | /* free space started in the previous sector! */ |
| 946 | |
| 947 | if((num_free_space < NUMFREEALLOWED) && |
| 948 | ((unsigned int)(test_start - start) >= fmc->sector_size)){ |
| 949 | |
| 950 | /* |
| 951 | Count it in if we are still under NUMFREEALLOWED *and* it is |
| 952 | at least 1 erase sector in length. This will keep us from |
| 953 | picking any little ole' space as "free". |
| 954 | */ |
| 955 | |
| 956 | D1(printk("Reducing end of free space to 0x%x from 0x%x\n", |
| 957 | (unsigned int)test_start, (unsigned int)pos)); |
| 958 | |
| 959 | D1(printk("Free space accepted: Starting 0x%x for 0x%x bytes\n", |
| 960 | (unsigned int) start, |
| 961 | (unsigned int)(test_start - start))); |
| 962 | |
| 963 | /* below, space from "start" to "pos" will be marked dirty. */ |
| 964 | start = test_start; |
| 965 | |
| 966 | /* Being in here means that we have found at least an entire |
| 967 | erase sector size of free space ending on a sector boundary. |
| 968 | Keep track of free spaces accepted. |
| 969 | */ |
| 970 | num_free_space++; |
| 971 | }else{ |
| 972 | num_free_spc_not_accp++; |
| 973 | D1(printk("Free space (#%i) found but *Not* accepted: Starting" |
| 974 | " 0x%x for 0x%x bytes\n", |
| 975 | num_free_spc_not_accp, (unsigned int)start, |
| 976 | (unsigned int)((unsigned int)(pos & ~(fmc->sector_size-1)) - (unsigned int)start))); |
| 977 | |
| 978 | } |
| 979 | |
| 980 | } |
| 981 | if((((__u32)(pos - start)) != 0)){ |
| 982 | |
| 983 | D1(printk("Dirty space: Starting 0x%x for 0x%x bytes\n", |
| 984 | (unsigned int) start, (unsigned int) (pos - start))); |
| 985 | jffs_fmalloced(fmc, (__u32) start, |
| 986 | (__u32) (pos - start), NULL); |
| 987 | }else{ |
| 988 | /* "Flipping bits" detected. This means that our scan for them |
| 989 | did not catch this offset. See check_partly_erased_sectors() for |
| 990 | more info. |
| 991 | */ |
| 992 | |
| 993 | D1(printk("jffs_scan_flash():wants to allocate dirty flash " |
| 994 | "space for 0 bytes.\n")); |
| 995 | D1(printk("jffs_scan_flash(): Flipping bits! We will free " |
| 996 | "all allocated memory, erase this sector and remount\n")); |
| 997 | |
| 998 | /* calculate start of present sector */ |
| 999 | offset = (((__u32)pos)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size; |
| 1000 | |
| 1001 | D1(printk("jffs_scan_flash():erasing sector starting 0x%x.\n", |
| 1002 | offset)); |
| 1003 | |
| 1004 | if (flash_erase_region(fmc->mtd, |
| 1005 | offset, fmc->sector_size) < 0) { |
| 1006 | printk(KERN_ERR "JFFS: Erase of flash failed. " |
| 1007 | "offset = %u, erase_size = %d\n", |
| 1008 | offset , fmc->sector_size); |
| 1009 | |
| 1010 | flash_safe_release(fmc->mtd); |
Jesper Juhl | f99d49a | 2005-11-07 01:01:34 -0800 | [diff] [blame] | 1011 | kfree(read_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1012 | return -1; /* bad, bad, bad! */ |
| 1013 | |
| 1014 | } |
| 1015 | flash_safe_release(fmc->mtd); |
Jesper Juhl | f99d49a | 2005-11-07 01:01:34 -0800 | [diff] [blame] | 1016 | kfree(read_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1017 | |
| 1018 | return -EAGAIN; /* erased offending sector. Try mount one more time please. */ |
| 1019 | } |
| 1020 | }else{ |
| 1021 | /* Being in here means that we have found free space that ends on an erase sector |
| 1022 | boundary. |
| 1023 | Count it in if we are still under NUMFREEALLOWED *and* it is at least 1 erase |
| 1024 | sector in length. This will keep us from picking any little ole' space as "free". |
| 1025 | */ |
| 1026 | if((num_free_space < NUMFREEALLOWED) && |
| 1027 | ((unsigned int)(pos - start) >= fmc->sector_size)){ |
| 1028 | /* We really don't do anything to mark space as free, except *not* |
| 1029 | mark it dirty and just advance the "pos" location pointer. |
| 1030 | It will automatically be picked up as free space. |
| 1031 | */ |
| 1032 | num_free_space++; |
| 1033 | D1(printk("Free space accepted: Starting 0x%x for 0x%x bytes\n", |
| 1034 | (unsigned int) start, (unsigned int) (pos - start))); |
| 1035 | }else{ |
| 1036 | num_free_spc_not_accp++; |
| 1037 | D1(printk("Free space (#%i) found but *Not* accepted: Starting " |
| 1038 | "0x%x for 0x%x bytes\n", num_free_spc_not_accp, |
| 1039 | (unsigned int) start, |
| 1040 | (unsigned int) (pos - start))); |
| 1041 | |
| 1042 | /* Mark this space as dirty. We already have our free space. */ |
| 1043 | D1(printk("Dirty space: Starting 0x%x for 0x%x bytes\n", |
| 1044 | (unsigned int) start, (unsigned int) (pos - start))); |
| 1045 | jffs_fmalloced(fmc, (__u32) start, |
| 1046 | (__u32) (pos - start), NULL); |
| 1047 | } |
| 1048 | |
| 1049 | } |
| 1050 | if(num_free_space > NUMFREEALLOWED){ |
| 1051 | printk(KERN_WARNING "jffs_scan_flash(): Found free space " |
| 1052 | "number %i. Only %i free space is allowed.\n", |
| 1053 | num_free_space, NUMFREEALLOWED); |
| 1054 | } |
| 1055 | continue; |
| 1056 | |
| 1057 | case JFFS_DIRTY_BITMASK: |
| 1058 | /* We have found 0x00000000 at this position. Scan as far |
| 1059 | as possible to find out how much is dirty. */ |
| 1060 | D1(printk("jffs_scan_flash(): 0x00000000 at pos 0x%lx.\n", |
| 1061 | (long)pos)); |
| 1062 | for (; pos < end |
| 1063 | && JFFS_DIRTY_BITMASK == flash_read_u32(fmc->mtd, pos); |
| 1064 | pos += 4); |
| 1065 | D1(printk("jffs_scan_flash(): 0x00 ended at " |
| 1066 | "pos 0x%lx.\n", (long)pos)); |
| 1067 | jffs_fmalloced(fmc, (__u32) start, |
| 1068 | (__u32) (pos - start), NULL); |
| 1069 | continue; |
| 1070 | |
| 1071 | case JFFS_MAGIC_BITMASK: |
| 1072 | /* We have probably found a new raw inode. */ |
| 1073 | break; |
| 1074 | |
| 1075 | default: |
| 1076 | bad_inode: |
| 1077 | /* We're f*cked. This is not solved yet. We have |
| 1078 | to scan for the magic pattern. */ |
| 1079 | D1(printk("*************** Dirty flash memory or " |
| 1080 | "bad inode: " |
| 1081 | "hexdump(pos = 0x%lx, len = 128):\n", |
| 1082 | (long)pos)); |
| 1083 | D1(jffs_hexdump(fmc->mtd, pos, 128)); |
| 1084 | |
| 1085 | for (pos += 4; pos < end; pos += 4) { |
| 1086 | switch (flash_read_u32(fmc->mtd, pos)) { |
| 1087 | case JFFS_MAGIC_BITMASK: |
| 1088 | case JFFS_EMPTY_BITMASK: |
| 1089 | /* handle these in the main switch() loop */ |
| 1090 | goto cont_scan; |
| 1091 | |
| 1092 | default: |
| 1093 | break; |
| 1094 | } |
| 1095 | } |
| 1096 | |
| 1097 | cont_scan: |
| 1098 | /* First, mark as dirty the region |
| 1099 | which really does contain crap. */ |
| 1100 | jffs_fmalloced(fmc, (__u32) start, |
| 1101 | (__u32) (pos - start), |
| 1102 | NULL); |
| 1103 | |
| 1104 | continue; |
| 1105 | }/* switch */ |
| 1106 | |
| 1107 | /* We have found the beginning of an inode. Create a |
| 1108 | node for it unless there already is one available. */ |
| 1109 | if (!node) { |
| 1110 | if (!(node = jffs_alloc_node())) { |
| 1111 | /* Free read buffer */ |
Jesper Juhl | f99d49a | 2005-11-07 01:01:34 -0800 | [diff] [blame] | 1112 | kfree(read_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1113 | |
| 1114 | /* Release the flash device */ |
| 1115 | flash_safe_release(fmc->mtd); |
| 1116 | |
| 1117 | return -ENOMEM; |
| 1118 | } |
| 1119 | DJM(no_jffs_node++); |
| 1120 | } |
| 1121 | |
| 1122 | /* Read the next raw inode. */ |
| 1123 | |
| 1124 | flash_safe_read(fmc->mtd, pos, (u_char *) &raw_inode, |
| 1125 | sizeof(struct jffs_raw_inode)); |
| 1126 | |
| 1127 | /* When we compute the checksum for the inode, we never |
| 1128 | count the 'accurate' or the 'checksum' fields. */ |
| 1129 | tmp_accurate = raw_inode.accurate; |
| 1130 | tmp_chksum = raw_inode.chksum; |
| 1131 | raw_inode.accurate = 0; |
| 1132 | raw_inode.chksum = 0; |
| 1133 | checksum = jffs_checksum(&raw_inode, |
| 1134 | sizeof(struct jffs_raw_inode)); |
| 1135 | raw_inode.accurate = tmp_accurate; |
| 1136 | raw_inode.chksum = tmp_chksum; |
| 1137 | |
| 1138 | D3(printk("*** We have found this raw inode at pos 0x%lx " |
| 1139 | "on the flash:\n", (long)pos)); |
| 1140 | D3(jffs_print_raw_inode(&raw_inode)); |
| 1141 | |
| 1142 | if (checksum != raw_inode.chksum) { |
| 1143 | D1(printk("jffs_scan_flash(): Bad checksum: " |
| 1144 | "checksum = %u, " |
| 1145 | "raw_inode.chksum = %u\n", |
| 1146 | checksum, raw_inode.chksum)); |
| 1147 | pos += sizeof(struct jffs_raw_inode); |
| 1148 | jffs_fmalloced(fmc, (__u32) start, |
| 1149 | (__u32) (pos - start), NULL); |
| 1150 | /* Reuse this unused struct jffs_node. */ |
| 1151 | continue; |
| 1152 | } |
| 1153 | |
| 1154 | /* Check the raw inode read so far. Start with the |
| 1155 | maximum length of the filename. */ |
| 1156 | if (raw_inode.nsize > JFFS_MAX_NAME_LEN) { |
| 1157 | printk(KERN_WARNING "jffs_scan_flash: Found a " |
| 1158 | "JFFS node with name too large\n"); |
| 1159 | goto bad_inode; |
| 1160 | } |
| 1161 | |
| 1162 | if (raw_inode.rename && raw_inode.dsize != sizeof(__u32)) { |
| 1163 | printk(KERN_WARNING "jffs_scan_flash: Found a " |
| 1164 | "rename node with dsize %u.\n", |
| 1165 | raw_inode.dsize); |
| 1166 | jffs_print_raw_inode(&raw_inode); |
| 1167 | goto bad_inode; |
| 1168 | } |
| 1169 | |
| 1170 | /* The node's data segment should not exceed a |
| 1171 | certain length. */ |
| 1172 | if (raw_inode.dsize > fmc->max_chunk_size) { |
| 1173 | printk(KERN_WARNING "jffs_scan_flash: Found a " |
| 1174 | "JFFS node with dsize (0x%x) > max_chunk_size (0x%x)\n", |
| 1175 | raw_inode.dsize, fmc->max_chunk_size); |
| 1176 | goto bad_inode; |
| 1177 | } |
| 1178 | |
| 1179 | pos += sizeof(struct jffs_raw_inode); |
| 1180 | |
| 1181 | /* This shouldn't be necessary because a node that |
| 1182 | violates the flash boundaries shouldn't be written |
| 1183 | in the first place. */ |
| 1184 | if (pos >= end) { |
| 1185 | goto check_node; |
| 1186 | } |
| 1187 | |
| 1188 | /* Read the name. */ |
| 1189 | *name = 0; |
| 1190 | if (raw_inode.nsize) { |
| 1191 | flash_safe_read(fmc->mtd, pos, name, raw_inode.nsize); |
| 1192 | name[raw_inode.nsize] = '\0'; |
| 1193 | pos += raw_inode.nsize |
| 1194 | + JFFS_GET_PAD_BYTES(raw_inode.nsize); |
| 1195 | D3(printk("name == \"%s\"\n", name)); |
| 1196 | checksum = jffs_checksum(name, raw_inode.nsize); |
| 1197 | if (checksum != raw_inode.nchksum) { |
| 1198 | D1(printk("jffs_scan_flash(): Bad checksum: " |
| 1199 | "checksum = %u, " |
| 1200 | "raw_inode.nchksum = %u\n", |
| 1201 | checksum, raw_inode.nchksum)); |
| 1202 | jffs_fmalloced(fmc, (__u32) start, |
| 1203 | (__u32) (pos - start), NULL); |
| 1204 | /* Reuse this unused struct jffs_node. */ |
| 1205 | continue; |
| 1206 | } |
| 1207 | if (pos >= end) { |
| 1208 | goto check_node; |
| 1209 | } |
| 1210 | } |
| 1211 | |
| 1212 | /* Read the data, if it exists, in order to be sure it |
| 1213 | matches the checksum. */ |
| 1214 | if (raw_inode.dsize) { |
| 1215 | if (raw_inode.rename) { |
| 1216 | deleted_file = flash_read_u32(fmc->mtd, pos); |
| 1217 | } |
| 1218 | if (jffs_checksum_flash(fmc->mtd, pos, raw_inode.dsize, &checksum)) { |
| 1219 | printk("jffs_checksum_flash() failed to calculate a checksum\n"); |
| 1220 | jffs_fmalloced(fmc, (__u32) start, |
| 1221 | (__u32) (pos - start), NULL); |
| 1222 | /* Reuse this unused struct jffs_node. */ |
| 1223 | continue; |
| 1224 | } |
| 1225 | pos += raw_inode.dsize |
| 1226 | + JFFS_GET_PAD_BYTES(raw_inode.dsize); |
| 1227 | |
| 1228 | if (checksum != raw_inode.dchksum) { |
| 1229 | D1(printk("jffs_scan_flash(): Bad checksum: " |
| 1230 | "checksum = %u, " |
| 1231 | "raw_inode.dchksum = %u\n", |
| 1232 | checksum, raw_inode.dchksum)); |
| 1233 | jffs_fmalloced(fmc, (__u32) start, |
| 1234 | (__u32) (pos - start), NULL); |
| 1235 | /* Reuse this unused struct jffs_node. */ |
| 1236 | continue; |
| 1237 | } |
| 1238 | } |
| 1239 | |
| 1240 | check_node: |
| 1241 | |
| 1242 | /* Remember the highest inode number in the whole file |
| 1243 | system. This information will be used when assigning |
| 1244 | new files new inode numbers. */ |
| 1245 | if (c->next_ino <= raw_inode.ino) { |
| 1246 | c->next_ino = raw_inode.ino + 1; |
| 1247 | } |
| 1248 | |
| 1249 | if (raw_inode.accurate) { |
| 1250 | int err; |
| 1251 | node->data_offset = raw_inode.offset; |
| 1252 | node->data_size = raw_inode.dsize; |
| 1253 | node->removed_size = raw_inode.rsize; |
| 1254 | /* Compute the offset to the actual data in the |
| 1255 | on-flash node. */ |
| 1256 | node->fm_offset |
| 1257 | = sizeof(struct jffs_raw_inode) |
| 1258 | + raw_inode.nsize |
| 1259 | + JFFS_GET_PAD_BYTES(raw_inode.nsize); |
| 1260 | node->fm = jffs_fmalloced(fmc, (__u32) start, |
| 1261 | (__u32) (pos - start), |
| 1262 | node); |
| 1263 | if (!node->fm) { |
| 1264 | D(printk("jffs_scan_flash(): !node->fm\n")); |
| 1265 | jffs_free_node(node); |
| 1266 | DJM(no_jffs_node--); |
| 1267 | |
| 1268 | /* Free read buffer */ |
Jesper Juhl | f99d49a | 2005-11-07 01:01:34 -0800 | [diff] [blame] | 1269 | kfree(read_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1270 | |
| 1271 | /* Release the flash device */ |
| 1272 | flash_safe_release(fmc->mtd); |
| 1273 | |
| 1274 | return -ENOMEM; |
| 1275 | } |
| 1276 | if ((err = jffs_insert_node(c, NULL, &raw_inode, |
| 1277 | name, node)) < 0) { |
| 1278 | printk("JFFS: Failed to handle raw inode. " |
| 1279 | "(err = %d)\n", err); |
| 1280 | break; |
| 1281 | } |
| 1282 | if (raw_inode.rename) { |
| 1283 | struct jffs_delete_list *dl |
| 1284 | = (struct jffs_delete_list *) |
| 1285 | kmalloc(sizeof(struct jffs_delete_list), |
| 1286 | GFP_KERNEL); |
| 1287 | if (!dl) { |
| 1288 | D(printk("jffs_scan_flash: !dl\n")); |
| 1289 | jffs_free_node(node); |
| 1290 | DJM(no_jffs_node--); |
| 1291 | |
| 1292 | /* Release the flash device */ |
| 1293 | flash_safe_release(fmc->flash_part); |
| 1294 | |
| 1295 | /* Free read buffer */ |
Jesper Juhl | f99d49a | 2005-11-07 01:01:34 -0800 | [diff] [blame] | 1296 | kfree(read_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1297 | |
| 1298 | return -ENOMEM; |
| 1299 | } |
| 1300 | dl->ino = deleted_file; |
| 1301 | dl->next = c->delete_list; |
| 1302 | c->delete_list = dl; |
| 1303 | node->data_size = 0; |
| 1304 | } |
| 1305 | D3(jffs_print_node(node)); |
| 1306 | node = NULL; /* Don't free the node! */ |
| 1307 | } |
| 1308 | else { |
| 1309 | jffs_fmalloced(fmc, (__u32) start, |
| 1310 | (__u32) (pos - start), NULL); |
| 1311 | D3(printk("jffs_scan_flash(): Just found an obsolete " |
| 1312 | "raw_inode. Continuing the scan...\n")); |
| 1313 | /* Reuse this unused struct jffs_node. */ |
| 1314 | } |
| 1315 | } |
| 1316 | |
| 1317 | if (node) { |
| 1318 | jffs_free_node(node); |
| 1319 | DJM(no_jffs_node--); |
| 1320 | } |
| 1321 | jffs_build_end(fmc); |
| 1322 | |
| 1323 | /* Free read buffer */ |
Jesper Juhl | f99d49a | 2005-11-07 01:01:34 -0800 | [diff] [blame] | 1324 | kfree(read_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1325 | |
| 1326 | if(!num_free_space){ |
| 1327 | printk(KERN_WARNING "jffs_scan_flash(): Did not find even a single " |
| 1328 | "chunk of free space. This is BAD!\n"); |
| 1329 | } |
| 1330 | |
| 1331 | /* Return happy */ |
| 1332 | D3(printk("jffs_scan_flash(): Leaving...\n")); |
| 1333 | flash_safe_release(fmc->mtd); |
| 1334 | |
| 1335 | /* This is to trap the "free size accounting screwed error. */ |
| 1336 | free_chunk_size1 = jffs_free_size1(fmc); |
| 1337 | free_chunk_size2 = jffs_free_size2(fmc); |
| 1338 | |
| 1339 | if (free_chunk_size1 + free_chunk_size2 != fmc->free_size) { |
| 1340 | |
| 1341 | printk(KERN_WARNING "jffs_scan_falsh():Free size accounting screwed\n"); |
| 1342 | printk(KERN_WARNING "jfffs_scan_flash():free_chunk_size1 == 0x%x, " |
| 1343 | "free_chunk_size2 == 0x%x, fmc->free_size == 0x%x\n", |
| 1344 | free_chunk_size1, free_chunk_size2, fmc->free_size); |
| 1345 | |
| 1346 | return -1; /* Do NOT mount f/s so that we can inspect what happened. |
| 1347 | Mounting this screwed up f/s will screw us up anyway. |
| 1348 | */ |
| 1349 | } |
| 1350 | |
| 1351 | return 0; /* as far as we are concerned, we are happy! */ |
| 1352 | } /* jffs_scan_flash() */ |
| 1353 | |
| 1354 | |
| 1355 | /* Insert any kind of node into the file system. Take care of data |
| 1356 | insertions and deletions. Also remove redundant information. The |
| 1357 | memory allocated for the `name' is regarded as "given away" in the |
| 1358 | caller's perspective. */ |
| 1359 | int |
| 1360 | jffs_insert_node(struct jffs_control *c, struct jffs_file *f, |
| 1361 | const struct jffs_raw_inode *raw_inode, |
| 1362 | const char *name, struct jffs_node *node) |
| 1363 | { |
| 1364 | int update_name = 0; |
| 1365 | int insert_into_tree = 0; |
| 1366 | |
| 1367 | D2(printk("jffs_insert_node(): ino = %u, version = %u, " |
| 1368 | "name = \"%s\", deleted = %d\n", |
| 1369 | raw_inode->ino, raw_inode->version, |
| 1370 | ((name && *name) ? name : ""), raw_inode->deleted)); |
| 1371 | |
| 1372 | /* If there doesn't exist an associated jffs_file, then |
| 1373 | create, initialize and insert one into the file system. */ |
| 1374 | if (!f && !(f = jffs_find_file(c, raw_inode->ino))) { |
| 1375 | if (!(f = jffs_create_file(c, raw_inode))) { |
| 1376 | return -ENOMEM; |
| 1377 | } |
| 1378 | jffs_insert_file_into_hash(f); |
| 1379 | insert_into_tree = 1; |
| 1380 | } |
| 1381 | node->ino = raw_inode->ino; |
| 1382 | node->version = raw_inode->version; |
| 1383 | node->data_size = raw_inode->dsize; |
| 1384 | node->fm_offset = sizeof(struct jffs_raw_inode) + raw_inode->nsize |
| 1385 | + JFFS_GET_PAD_BYTES(raw_inode->nsize); |
| 1386 | node->name_size = raw_inode->nsize; |
| 1387 | |
| 1388 | /* Now insert the node at the correct position into the file's |
| 1389 | version list. */ |
| 1390 | if (!f->version_head) { |
| 1391 | /* This is the first node. */ |
| 1392 | f->version_head = node; |
| 1393 | f->version_tail = node; |
| 1394 | node->version_prev = NULL; |
| 1395 | node->version_next = NULL; |
| 1396 | f->highest_version = node->version; |
| 1397 | update_name = 1; |
| 1398 | f->mode = raw_inode->mode; |
| 1399 | f->uid = raw_inode->uid; |
| 1400 | f->gid = raw_inode->gid; |
| 1401 | f->atime = raw_inode->atime; |
| 1402 | f->mtime = raw_inode->mtime; |
| 1403 | f->ctime = raw_inode->ctime; |
| 1404 | } |
| 1405 | else if ((f->highest_version < node->version) |
| 1406 | || (node->version == 0)) { |
| 1407 | /* Insert at the end of the list. I.e. this node is the |
| 1408 | newest one so far. */ |
| 1409 | node->version_prev = f->version_tail; |
| 1410 | node->version_next = NULL; |
| 1411 | f->version_tail->version_next = node; |
| 1412 | f->version_tail = node; |
| 1413 | f->highest_version = node->version; |
| 1414 | update_name = 1; |
| 1415 | f->pino = raw_inode->pino; |
| 1416 | f->mode = raw_inode->mode; |
| 1417 | f->uid = raw_inode->uid; |
| 1418 | f->gid = raw_inode->gid; |
| 1419 | f->atime = raw_inode->atime; |
| 1420 | f->mtime = raw_inode->mtime; |
| 1421 | f->ctime = raw_inode->ctime; |
| 1422 | } |
| 1423 | else if (f->version_head->version > node->version) { |
| 1424 | /* Insert at the bottom of the list. */ |
| 1425 | node->version_prev = NULL; |
| 1426 | node->version_next = f->version_head; |
| 1427 | f->version_head->version_prev = node; |
| 1428 | f->version_head = node; |
| 1429 | if (!f->name) { |
| 1430 | update_name = 1; |
| 1431 | } |
| 1432 | } |
| 1433 | else { |
| 1434 | struct jffs_node *n; |
| 1435 | int newer_name = 0; |
| 1436 | /* Search for the insertion position starting from |
| 1437 | the tail (newest node). */ |
| 1438 | for (n = f->version_tail; n; n = n->version_prev) { |
| 1439 | if (n->version < node->version) { |
| 1440 | node->version_prev = n; |
| 1441 | node->version_next = n->version_next; |
| 1442 | node->version_next->version_prev = node; |
| 1443 | n->version_next = node; |
| 1444 | if (!newer_name) { |
| 1445 | update_name = 1; |
| 1446 | } |
| 1447 | break; |
| 1448 | } |
| 1449 | if (n->name_size) { |
| 1450 | newer_name = 1; |
| 1451 | } |
| 1452 | } |
| 1453 | } |
| 1454 | |
| 1455 | /* Deletion is irreversible. If any 'deleted' node is ever |
| 1456 | written, the file is deleted */ |
| 1457 | if (raw_inode->deleted) |
| 1458 | f->deleted = raw_inode->deleted; |
| 1459 | |
| 1460 | /* Perhaps update the name. */ |
| 1461 | if (raw_inode->nsize && update_name && name && *name && (name != f->name)) { |
| 1462 | if (f->name) { |
| 1463 | kfree(f->name); |
| 1464 | DJM(no_name--); |
| 1465 | } |
| 1466 | if (!(f->name = (char *) kmalloc(raw_inode->nsize + 1, |
| 1467 | GFP_KERNEL))) { |
| 1468 | return -ENOMEM; |
| 1469 | } |
| 1470 | DJM(no_name++); |
| 1471 | memcpy(f->name, name, raw_inode->nsize); |
| 1472 | f->name[raw_inode->nsize] = '\0'; |
| 1473 | f->nsize = raw_inode->nsize; |
| 1474 | D3(printk("jffs_insert_node(): Updated the name of " |
| 1475 | "the file to \"%s\".\n", name)); |
| 1476 | } |
| 1477 | |
| 1478 | if (!c->building_fs) { |
| 1479 | D3(printk("jffs_insert_node(): ---------------------------" |
| 1480 | "------------------------------------------- 1\n")); |
| 1481 | if (insert_into_tree) { |
| 1482 | jffs_insert_file_into_tree(f); |
| 1483 | } |
| 1484 | /* Once upon a time, we would call jffs_possibly_delete_file() |
| 1485 | here. That causes an oops if someone's still got the file |
| 1486 | open, so now we only do it in jffs_delete_inode() |
| 1487 | -- dwmw2 |
| 1488 | */ |
| 1489 | if (node->data_size || node->removed_size) { |
| 1490 | jffs_update_file(f, node); |
| 1491 | } |
| 1492 | jffs_remove_redundant_nodes(f); |
| 1493 | |
| 1494 | jffs_garbage_collect_trigger(c); |
| 1495 | |
| 1496 | D3(printk("jffs_insert_node(): ---------------------------" |
| 1497 | "------------------------------------------- 2\n")); |
| 1498 | } |
| 1499 | |
| 1500 | return 0; |
| 1501 | } /* jffs_insert_node() */ |
| 1502 | |
| 1503 | |
| 1504 | /* Unlink a jffs_node from the version list it is in. */ |
| 1505 | static inline void |
| 1506 | jffs_unlink_node_from_version_list(struct jffs_file *f, |
| 1507 | struct jffs_node *node) |
| 1508 | { |
| 1509 | if (node->version_prev) { |
| 1510 | node->version_prev->version_next = node->version_next; |
| 1511 | } else { |
| 1512 | f->version_head = node->version_next; |
| 1513 | } |
| 1514 | if (node->version_next) { |
| 1515 | node->version_next->version_prev = node->version_prev; |
| 1516 | } else { |
| 1517 | f->version_tail = node->version_prev; |
| 1518 | } |
| 1519 | } |
| 1520 | |
| 1521 | |
| 1522 | /* Unlink a jffs_node from the range list it is in. */ |
| 1523 | static inline void |
| 1524 | jffs_unlink_node_from_range_list(struct jffs_file *f, struct jffs_node *node) |
| 1525 | { |
| 1526 | if (node->range_prev) { |
| 1527 | node->range_prev->range_next = node->range_next; |
| 1528 | } |
| 1529 | else { |
| 1530 | f->range_head = node->range_next; |
| 1531 | } |
| 1532 | if (node->range_next) { |
| 1533 | node->range_next->range_prev = node->range_prev; |
| 1534 | } |
| 1535 | else { |
| 1536 | f->range_tail = node->range_prev; |
| 1537 | } |
| 1538 | } |
| 1539 | |
| 1540 | |
| 1541 | /* Function used by jffs_remove_redundant_nodes() below. This function |
| 1542 | classifies what kind of information a node adds to a file. */ |
| 1543 | static inline __u8 |
| 1544 | jffs_classify_node(struct jffs_node *node) |
| 1545 | { |
| 1546 | __u8 mod_type = JFFS_MODIFY_INODE; |
| 1547 | |
| 1548 | if (node->name_size) { |
| 1549 | mod_type |= JFFS_MODIFY_NAME; |
| 1550 | } |
| 1551 | if (node->data_size || node->removed_size) { |
| 1552 | mod_type |= JFFS_MODIFY_DATA; |
| 1553 | } |
| 1554 | return mod_type; |
| 1555 | } |
| 1556 | |
| 1557 | |
| 1558 | /* Remove redundant nodes from a file. Mark the on-flash memory |
| 1559 | as dirty. */ |
| 1560 | static int |
| 1561 | jffs_remove_redundant_nodes(struct jffs_file *f) |
| 1562 | { |
| 1563 | struct jffs_node *newest_node; |
| 1564 | struct jffs_node *cur; |
| 1565 | struct jffs_node *prev; |
| 1566 | __u8 newest_type; |
| 1567 | __u8 mod_type; |
| 1568 | __u8 node_with_name_later = 0; |
| 1569 | |
| 1570 | if (!(newest_node = f->version_tail)) { |
| 1571 | return 0; |
| 1572 | } |
| 1573 | |
| 1574 | /* What does the `newest_node' modify? */ |
| 1575 | newest_type = jffs_classify_node(newest_node); |
| 1576 | node_with_name_later = newest_type & JFFS_MODIFY_NAME; |
| 1577 | |
| 1578 | D3(printk("jffs_remove_redundant_nodes(): ino: %u, name: \"%s\", " |
| 1579 | "newest_type: %u\n", f->ino, (f->name ? f->name : ""), |
| 1580 | newest_type)); |
| 1581 | |
| 1582 | /* Traverse the file's nodes and determine which of them that are |
| 1583 | superfluous. Yeah, this might look very complex at first |
| 1584 | glance but it is actually very simple. */ |
| 1585 | for (cur = newest_node->version_prev; cur; cur = prev) { |
| 1586 | prev = cur->version_prev; |
| 1587 | mod_type = jffs_classify_node(cur); |
| 1588 | if ((mod_type <= JFFS_MODIFY_INODE) |
| 1589 | || ((newest_type & JFFS_MODIFY_NAME) |
| 1590 | && (mod_type |
| 1591 | <= (JFFS_MODIFY_INODE + JFFS_MODIFY_NAME))) |
| 1592 | || (cur->data_size == 0 && cur->removed_size |
| 1593 | && !cur->version_prev && node_with_name_later)) { |
| 1594 | /* Yes, this node is redundant. Remove it. */ |
| 1595 | D2(printk("jffs_remove_redundant_nodes(): " |
| 1596 | "Removing node: ino: %u, version: %u, " |
| 1597 | "mod_type: %u\n", cur->ino, cur->version, |
| 1598 | mod_type)); |
| 1599 | jffs_unlink_node_from_version_list(f, cur); |
| 1600 | jffs_fmfree(f->c->fmc, cur->fm, cur); |
| 1601 | jffs_free_node(cur); |
| 1602 | DJM(no_jffs_node--); |
| 1603 | } |
| 1604 | else { |
| 1605 | node_with_name_later |= (mod_type & JFFS_MODIFY_NAME); |
| 1606 | } |
| 1607 | } |
| 1608 | |
| 1609 | return 0; |
| 1610 | } |
| 1611 | |
| 1612 | |
| 1613 | /* Insert a file into the hash table. */ |
| 1614 | static int |
| 1615 | jffs_insert_file_into_hash(struct jffs_file *f) |
| 1616 | { |
| 1617 | int i = f->ino % f->c->hash_len; |
| 1618 | |
| 1619 | D3(printk("jffs_insert_file_into_hash(): f->ino: %u\n", f->ino)); |
| 1620 | |
| 1621 | list_add(&f->hash, &f->c->hash[i]); |
| 1622 | return 0; |
| 1623 | } |
| 1624 | |
| 1625 | |
| 1626 | /* Insert a file into the file system tree. */ |
| 1627 | int |
| 1628 | jffs_insert_file_into_tree(struct jffs_file *f) |
| 1629 | { |
| 1630 | struct jffs_file *parent; |
| 1631 | |
| 1632 | D3(printk("jffs_insert_file_into_tree(): name: \"%s\"\n", |
| 1633 | (f->name ? f->name : ""))); |
| 1634 | |
| 1635 | if (!(parent = jffs_find_file(f->c, f->pino))) { |
| 1636 | if (f->pino == 0) { |
| 1637 | f->c->root = f; |
| 1638 | f->parent = NULL; |
| 1639 | f->sibling_prev = NULL; |
| 1640 | f->sibling_next = NULL; |
| 1641 | return 0; |
| 1642 | } |
| 1643 | else { |
| 1644 | D1(printk("jffs_insert_file_into_tree(): Found " |
| 1645 | "inode with no parent and pino == %u\n", |
| 1646 | f->pino)); |
| 1647 | return -1; |
| 1648 | } |
| 1649 | } |
| 1650 | f->parent = parent; |
| 1651 | f->sibling_next = parent->children; |
| 1652 | if (f->sibling_next) { |
| 1653 | f->sibling_next->sibling_prev = f; |
| 1654 | } |
| 1655 | f->sibling_prev = NULL; |
| 1656 | parent->children = f; |
| 1657 | return 0; |
| 1658 | } |
| 1659 | |
| 1660 | |
| 1661 | /* Remove a file from the hash table. */ |
| 1662 | static int |
| 1663 | jffs_unlink_file_from_hash(struct jffs_file *f) |
| 1664 | { |
| 1665 | D3(printk("jffs_unlink_file_from_hash(): f: 0x%p, " |
| 1666 | "ino %u\n", f, f->ino)); |
| 1667 | |
| 1668 | list_del(&f->hash); |
| 1669 | return 0; |
| 1670 | } |
| 1671 | |
| 1672 | |
| 1673 | /* Just remove the file from the parent's children. Don't free |
| 1674 | any memory. */ |
| 1675 | int |
| 1676 | jffs_unlink_file_from_tree(struct jffs_file *f) |
| 1677 | { |
| 1678 | D3(printk("jffs_unlink_file_from_tree(): ino: %d, pino: %d, name: " |
| 1679 | "\"%s\"\n", f->ino, f->pino, (f->name ? f->name : ""))); |
| 1680 | |
| 1681 | if (f->sibling_prev) { |
| 1682 | f->sibling_prev->sibling_next = f->sibling_next; |
| 1683 | } |
| 1684 | else if (f->parent) { |
| 1685 | D3(printk("f->parent=%p\n", f->parent)); |
| 1686 | f->parent->children = f->sibling_next; |
| 1687 | } |
| 1688 | if (f->sibling_next) { |
| 1689 | f->sibling_next->sibling_prev = f->sibling_prev; |
| 1690 | } |
| 1691 | return 0; |
| 1692 | } |
| 1693 | |
| 1694 | |
| 1695 | /* Find a file with its inode number. */ |
| 1696 | struct jffs_file * |
| 1697 | jffs_find_file(struct jffs_control *c, __u32 ino) |
| 1698 | { |
| 1699 | struct jffs_file *f; |
| 1700 | int i = ino % c->hash_len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1701 | |
| 1702 | D3(printk("jffs_find_file(): ino: %u\n", ino)); |
| 1703 | |
Domen Puncer | 216d81b | 2005-09-10 00:27:05 -0700 | [diff] [blame] | 1704 | list_for_each_entry(f, &c->hash[i], hash) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1705 | if (ino != f->ino) |
| 1706 | continue; |
| 1707 | D3(printk("jffs_find_file(): Found file with ino " |
| 1708 | "%u. (name: \"%s\")\n", |
| 1709 | ino, (f->name ? f->name : "")); |
| 1710 | ); |
| 1711 | return f; |
| 1712 | } |
| 1713 | D3(printk("jffs_find_file(): Didn't find file " |
| 1714 | "with ino %u.\n", ino); |
| 1715 | ); |
| 1716 | return NULL; |
| 1717 | } |
| 1718 | |
| 1719 | |
| 1720 | /* Find a file in a directory. We are comparing the names. */ |
| 1721 | struct jffs_file * |
| 1722 | jffs_find_child(struct jffs_file *dir, const char *name, int len) |
| 1723 | { |
| 1724 | struct jffs_file *f; |
| 1725 | |
| 1726 | D3(printk("jffs_find_child()\n")); |
| 1727 | |
| 1728 | for (f = dir->children; f; f = f->sibling_next) { |
| 1729 | if (!f->deleted && f->name |
| 1730 | && !strncmp(f->name, name, len) |
| 1731 | && f->name[len] == '\0') { |
| 1732 | break; |
| 1733 | } |
| 1734 | } |
| 1735 | |
| 1736 | D3(if (f) { |
| 1737 | printk("jffs_find_child(): Found \"%s\".\n", f->name); |
| 1738 | } |
| 1739 | else { |
| 1740 | char *copy = (char *) kmalloc(len + 1, GFP_KERNEL); |
| 1741 | if (copy) { |
| 1742 | memcpy(copy, name, len); |
| 1743 | copy[len] = '\0'; |
| 1744 | } |
| 1745 | printk("jffs_find_child(): Didn't find the file \"%s\".\n", |
| 1746 | (copy ? copy : "")); |
Jesper Juhl | f99d49a | 2005-11-07 01:01:34 -0800 | [diff] [blame] | 1747 | kfree(copy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1748 | }); |
| 1749 | |
| 1750 | return f; |
| 1751 | } |
| 1752 | |
| 1753 | |
| 1754 | /* Write a raw inode that takes up a certain amount of space in the flash |
| 1755 | memory. At the end of the flash device, there is often space that is |
| 1756 | impossible to use. At these times we want to mark this space as not |
| 1757 | used. In the cases when the amount of space is greater or equal than |
| 1758 | a struct jffs_raw_inode, we write a "dummy node" that takes up this |
| 1759 | space. The space after the raw inode, if it exists, is left as it is. |
| 1760 | Since this space after the raw inode contains JFFS_EMPTY_BITMASK bytes, |
| 1761 | we can compute the checksum of it; we don't have to manipulate it any |
| 1762 | further. |
| 1763 | |
| 1764 | If the space left on the device is less than the size of a struct |
| 1765 | jffs_raw_inode, this space is filled with JFFS_DIRTY_BITMASK bytes. |
| 1766 | No raw inode is written this time. */ |
| 1767 | static int |
| 1768 | jffs_write_dummy_node(struct jffs_control *c, struct jffs_fm *dirty_fm) |
| 1769 | { |
| 1770 | struct jffs_fmcontrol *fmc = c->fmc; |
| 1771 | int err; |
| 1772 | |
| 1773 | D1(printk("jffs_write_dummy_node(): dirty_fm->offset = 0x%08x, " |
| 1774 | "dirty_fm->size = %u\n", |
| 1775 | dirty_fm->offset, dirty_fm->size)); |
| 1776 | |
| 1777 | if (dirty_fm->size >= sizeof(struct jffs_raw_inode)) { |
| 1778 | struct jffs_raw_inode raw_inode; |
| 1779 | memset(&raw_inode, 0, sizeof(struct jffs_raw_inode)); |
| 1780 | raw_inode.magic = JFFS_MAGIC_BITMASK; |
| 1781 | raw_inode.dsize = dirty_fm->size |
| 1782 | - sizeof(struct jffs_raw_inode); |
| 1783 | raw_inode.dchksum = raw_inode.dsize * 0xff; |
| 1784 | raw_inode.chksum |
| 1785 | = jffs_checksum(&raw_inode, sizeof(struct jffs_raw_inode)); |
| 1786 | |
| 1787 | if ((err = flash_safe_write(fmc->mtd, |
| 1788 | dirty_fm->offset, |
| 1789 | (u_char *)&raw_inode, |
| 1790 | sizeof(struct jffs_raw_inode))) |
| 1791 | < 0) { |
| 1792 | printk(KERN_ERR "JFFS: jffs_write_dummy_node: " |
| 1793 | "flash_safe_write failed!\n"); |
| 1794 | return err; |
| 1795 | } |
| 1796 | } |
| 1797 | else { |
| 1798 | flash_safe_acquire(fmc->mtd); |
| 1799 | flash_memset(fmc->mtd, dirty_fm->offset, 0, dirty_fm->size); |
| 1800 | flash_safe_release(fmc->mtd); |
| 1801 | } |
| 1802 | |
| 1803 | D3(printk("jffs_write_dummy_node(): Leaving...\n")); |
| 1804 | return 0; |
| 1805 | } |
| 1806 | |
| 1807 | |
| 1808 | /* Write a raw inode, possibly its name and possibly some data. */ |
| 1809 | int |
| 1810 | jffs_write_node(struct jffs_control *c, struct jffs_node *node, |
| 1811 | struct jffs_raw_inode *raw_inode, |
| 1812 | const char *name, const unsigned char *data, |
| 1813 | int recoverable, |
| 1814 | struct jffs_file *f) |
| 1815 | { |
| 1816 | struct jffs_fmcontrol *fmc = c->fmc; |
| 1817 | struct jffs_fm *fm; |
| 1818 | struct kvec node_iovec[4]; |
| 1819 | unsigned long iovec_cnt; |
| 1820 | |
| 1821 | __u32 pos; |
| 1822 | int err; |
| 1823 | __u32 slack = 0; |
| 1824 | |
| 1825 | __u32 total_name_size = raw_inode->nsize |
| 1826 | + JFFS_GET_PAD_BYTES(raw_inode->nsize); |
| 1827 | __u32 total_data_size = raw_inode->dsize |
| 1828 | + JFFS_GET_PAD_BYTES(raw_inode->dsize); |
| 1829 | __u32 total_size = sizeof(struct jffs_raw_inode) |
| 1830 | + total_name_size + total_data_size; |
| 1831 | |
| 1832 | /* If this node isn't something that will eventually let |
| 1833 | GC free even more space, then don't allow it unless |
| 1834 | there's at least max_chunk_size space still available |
| 1835 | */ |
| 1836 | if (!recoverable) |
| 1837 | slack = fmc->max_chunk_size; |
| 1838 | |
| 1839 | |
| 1840 | /* Fire the retrorockets and shoot the fruiton torpedoes, sir! */ |
| 1841 | |
| 1842 | ASSERT(if (!node) { |
| 1843 | printk("jffs_write_node(): node == NULL\n"); |
| 1844 | return -EINVAL; |
| 1845 | }); |
| 1846 | ASSERT(if (raw_inode && raw_inode->nsize && !name) { |
| 1847 | printk("*** jffs_write_node(): nsize = %u but name == NULL\n", |
| 1848 | raw_inode->nsize); |
| 1849 | return -EINVAL; |
| 1850 | }); |
| 1851 | |
| 1852 | D1(printk("jffs_write_node(): filename = \"%s\", ino = %u, " |
| 1853 | "total_size = %u\n", |
| 1854 | (name ? name : ""), raw_inode->ino, |
| 1855 | total_size)); |
| 1856 | |
| 1857 | jffs_fm_write_lock(fmc); |
| 1858 | |
| 1859 | retry: |
| 1860 | fm = NULL; |
| 1861 | err = 0; |
| 1862 | while (!fm) { |
| 1863 | |
| 1864 | /* Deadlocks suck. */ |
| 1865 | while(fmc->free_size < fmc->min_free_size + total_size + slack) { |
| 1866 | jffs_fm_write_unlock(fmc); |
| 1867 | if (!JFFS_ENOUGH_SPACE(c, total_size + slack)) |
| 1868 | return -ENOSPC; |
| 1869 | jffs_fm_write_lock(fmc); |
| 1870 | } |
| 1871 | |
| 1872 | /* First try to allocate some flash memory. */ |
| 1873 | err = jffs_fmalloc(fmc, total_size, node, &fm); |
| 1874 | |
| 1875 | if (err == -ENOSPC) { |
| 1876 | /* Just out of space. GC and try again */ |
| 1877 | if (fmc->dirty_size < fmc->sector_size) { |
| 1878 | D(printk("jffs_write_node(): jffs_fmalloc(0x%p, %u) " |
| 1879 | "failed, no dirty space to GC\n", fmc, |
| 1880 | total_size)); |
| 1881 | return err; |
| 1882 | } |
| 1883 | |
| 1884 | D1(printk(KERN_INFO "jffs_write_node(): Calling jffs_garbage_collect_now()\n")); |
| 1885 | jffs_fm_write_unlock(fmc); |
| 1886 | if ((err = jffs_garbage_collect_now(c))) { |
| 1887 | D(printk("jffs_write_node(): jffs_garbage_collect_now() failed\n")); |
| 1888 | return err; |
| 1889 | } |
| 1890 | jffs_fm_write_lock(fmc); |
| 1891 | continue; |
| 1892 | } |
| 1893 | |
| 1894 | if (err < 0) { |
| 1895 | jffs_fm_write_unlock(fmc); |
| 1896 | |
| 1897 | D(printk("jffs_write_node(): jffs_fmalloc(0x%p, %u) " |
| 1898 | "failed!\n", fmc, total_size)); |
| 1899 | return err; |
| 1900 | } |
| 1901 | |
| 1902 | if (!fm->nodes) { |
| 1903 | /* The jffs_fm struct that we got is not good enough. |
| 1904 | Make that space dirty and try again */ |
| 1905 | if ((err = jffs_write_dummy_node(c, fm)) < 0) { |
| 1906 | kfree(fm); |
| 1907 | DJM(no_jffs_fm--); |
| 1908 | jffs_fm_write_unlock(fmc); |
| 1909 | D(printk("jffs_write_node(): " |
| 1910 | "jffs_write_dummy_node(): Failed!\n")); |
| 1911 | return err; |
| 1912 | } |
| 1913 | fm = NULL; |
| 1914 | } |
| 1915 | } /* while(!fm) */ |
| 1916 | node->fm = fm; |
| 1917 | |
| 1918 | ASSERT(if (fm->nodes == 0) { |
| 1919 | printk(KERN_ERR "jffs_write_node(): fm->nodes == 0\n"); |
| 1920 | }); |
| 1921 | |
| 1922 | pos = node->fm->offset; |
| 1923 | |
| 1924 | /* Increment the version number here. We can't let the caller |
| 1925 | set it beforehand, because we might have had to do GC on a node |
| 1926 | of this file - and we'd end up reusing version numbers. |
| 1927 | */ |
| 1928 | if (f) { |
| 1929 | raw_inode->version = f->highest_version + 1; |
| 1930 | D1(printk (KERN_NOTICE "jffs_write_node(): setting version of %s to %d\n", f->name, raw_inode->version)); |
| 1931 | |
| 1932 | /* if the file was deleted, set the deleted bit in the raw inode */ |
| 1933 | if (f->deleted) |
| 1934 | raw_inode->deleted = 1; |
| 1935 | } |
| 1936 | |
| 1937 | /* Compute the checksum for the data and name chunks. */ |
| 1938 | raw_inode->dchksum = jffs_checksum(data, raw_inode->dsize); |
| 1939 | raw_inode->nchksum = jffs_checksum(name, raw_inode->nsize); |
| 1940 | |
| 1941 | /* The checksum is calculated without the chksum and accurate |
| 1942 | fields so set them to zero first. */ |
| 1943 | raw_inode->accurate = 0; |
| 1944 | raw_inode->chksum = 0; |
| 1945 | raw_inode->chksum = jffs_checksum(raw_inode, |
| 1946 | sizeof(struct jffs_raw_inode)); |
| 1947 | raw_inode->accurate = 0xff; |
| 1948 | |
| 1949 | D3(printk("jffs_write_node(): About to write this raw inode to the " |
| 1950 | "flash at pos 0x%lx:\n", (long)pos)); |
| 1951 | D3(jffs_print_raw_inode(raw_inode)); |
| 1952 | |
| 1953 | /* The actual raw JFFS node */ |
| 1954 | node_iovec[0].iov_base = (void *) raw_inode; |
| 1955 | node_iovec[0].iov_len = (size_t) sizeof(struct jffs_raw_inode); |
| 1956 | iovec_cnt = 1; |
| 1957 | |
| 1958 | /* Get name and size if there is one */ |
| 1959 | if (raw_inode->nsize) { |
| 1960 | node_iovec[iovec_cnt].iov_base = (void *) name; |
| 1961 | node_iovec[iovec_cnt].iov_len = (size_t) raw_inode->nsize; |
| 1962 | iovec_cnt++; |
| 1963 | |
| 1964 | if (JFFS_GET_PAD_BYTES(raw_inode->nsize)) { |
Felix Oxley | bd3bfeb | 2006-02-03 03:04:15 -0800 | [diff] [blame] | 1965 | static unsigned char allff[3]={255,255,255}; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1966 | /* Add some extra padding if necessary */ |
| 1967 | node_iovec[iovec_cnt].iov_base = allff; |
| 1968 | node_iovec[iovec_cnt].iov_len = |
| 1969 | JFFS_GET_PAD_BYTES(raw_inode->nsize); |
| 1970 | iovec_cnt++; |
| 1971 | } |
| 1972 | } |
| 1973 | |
| 1974 | /* Get data and size if there is any */ |
| 1975 | if (raw_inode->dsize) { |
| 1976 | node_iovec[iovec_cnt].iov_base = (void *) data; |
| 1977 | node_iovec[iovec_cnt].iov_len = (size_t) raw_inode->dsize; |
| 1978 | iovec_cnt++; |
| 1979 | /* No need to pad this because we're not actually putting |
| 1980 | anything after it. |
| 1981 | */ |
| 1982 | } |
| 1983 | |
| 1984 | if ((err = flash_safe_writev(fmc->mtd, node_iovec, iovec_cnt, |
| 1985 | pos)) < 0) { |
| 1986 | jffs_fmfree_partly(fmc, fm, 0); |
| 1987 | jffs_fm_write_unlock(fmc); |
| 1988 | printk(KERN_ERR "JFFS: jffs_write_node: Failed to write, " |
| 1989 | "requested %i, wrote %i\n", total_size, err); |
| 1990 | goto retry; |
| 1991 | } |
| 1992 | if (raw_inode->deleted) |
| 1993 | f->deleted = 1; |
| 1994 | |
| 1995 | jffs_fm_write_unlock(fmc); |
| 1996 | D3(printk("jffs_write_node(): Leaving...\n")); |
| 1997 | return raw_inode->dsize; |
| 1998 | } /* jffs_write_node() */ |
| 1999 | |
| 2000 | |
| 2001 | /* Read data from the node and write it to the buffer. 'node_offset' |
| 2002 | is how much we have read from this particular node before and which |
| 2003 | shouldn't be read again. 'max_size' is how much space there is in |
| 2004 | the buffer. */ |
| 2005 | static int |
| 2006 | jffs_get_node_data(struct jffs_file *f, struct jffs_node *node, |
| 2007 | unsigned char *buf,__u32 node_offset, __u32 max_size) |
| 2008 | { |
| 2009 | struct jffs_fmcontrol *fmc = f->c->fmc; |
| 2010 | __u32 pos = node->fm->offset + node->fm_offset + node_offset; |
| 2011 | __u32 avail = node->data_size - node_offset; |
| 2012 | __u32 r; |
| 2013 | |
| 2014 | D2(printk(" jffs_get_node_data(): file: \"%s\", ino: %u, " |
| 2015 | "version: %u, node_offset: %u\n", |
| 2016 | f->name, node->ino, node->version, node_offset)); |
| 2017 | |
| 2018 | r = min(avail, max_size); |
| 2019 | D3(printk(KERN_NOTICE "jffs_get_node_data\n")); |
| 2020 | flash_safe_read(fmc->mtd, pos, buf, r); |
| 2021 | |
| 2022 | D3(printk(" jffs_get_node_data(): Read %u byte%s.\n", |
| 2023 | r, (r == 1 ? "" : "s"))); |
| 2024 | |
| 2025 | return r; |
| 2026 | } |
| 2027 | |
| 2028 | |
| 2029 | /* Read data from the file's nodes. Write the data to the buffer |
| 2030 | 'buf'. 'read_offset' tells how much data we should skip. */ |
| 2031 | int |
| 2032 | jffs_read_data(struct jffs_file *f, unsigned char *buf, __u32 read_offset, |
| 2033 | __u32 size) |
| 2034 | { |
| 2035 | struct jffs_node *node; |
| 2036 | __u32 read_data = 0; /* Total amount of read data. */ |
| 2037 | __u32 node_offset = 0; |
| 2038 | __u32 pos = 0; /* Number of bytes traversed. */ |
| 2039 | |
| 2040 | D2(printk("jffs_read_data(): file = \"%s\", read_offset = %d, " |
| 2041 | "size = %u\n", |
| 2042 | (f->name ? f->name : ""), read_offset, size)); |
| 2043 | |
| 2044 | if (read_offset >= f->size) { |
| 2045 | D(printk(" f->size: %d\n", f->size)); |
| 2046 | return 0; |
| 2047 | } |
| 2048 | |
| 2049 | /* First find the node to read data from. */ |
| 2050 | node = f->range_head; |
| 2051 | while (pos <= read_offset) { |
| 2052 | node_offset = read_offset - pos; |
| 2053 | if (node_offset >= node->data_size) { |
| 2054 | pos += node->data_size; |
| 2055 | node = node->range_next; |
| 2056 | } |
| 2057 | else { |
| 2058 | break; |
| 2059 | } |
| 2060 | } |
| 2061 | |
| 2062 | /* "Cats are living proof that not everything in nature |
| 2063 | has to be useful." |
| 2064 | - Garrison Keilor ('97) */ |
| 2065 | |
| 2066 | /* Fill the buffer. */ |
| 2067 | while (node && (read_data < size)) { |
| 2068 | int r; |
| 2069 | if (!node->fm) { |
| 2070 | /* This node does not refer to real data. */ |
| 2071 | r = min(size - read_data, |
| 2072 | node->data_size - node_offset); |
| 2073 | memset(&buf[read_data], 0, r); |
| 2074 | } |
| 2075 | else if ((r = jffs_get_node_data(f, node, &buf[read_data], |
| 2076 | node_offset, |
| 2077 | size - read_data)) < 0) { |
| 2078 | return r; |
| 2079 | } |
| 2080 | read_data += r; |
| 2081 | node_offset = 0; |
| 2082 | node = node->range_next; |
| 2083 | } |
| 2084 | D3(printk(" jffs_read_data(): Read %u bytes.\n", read_data)); |
| 2085 | return read_data; |
| 2086 | } |
| 2087 | |
| 2088 | |
| 2089 | /* Used for traversing all nodes in the hash table. */ |
| 2090 | int |
| 2091 | jffs_foreach_file(struct jffs_control *c, int (*func)(struct jffs_file *)) |
| 2092 | { |
| 2093 | int pos; |
| 2094 | int r; |
| 2095 | int result = 0; |
| 2096 | |
| 2097 | for (pos = 0; pos < c->hash_len; pos++) { |
Domen Puncer | 216d81b | 2005-09-10 00:27:05 -0700 | [diff] [blame] | 2098 | struct jffs_file *f, *next; |
| 2099 | |
| 2100 | /* We must do _safe, because 'func' might remove the |
| 2101 | current file 'f' from the list. */ |
| 2102 | list_for_each_entry_safe(f, next, &c->hash[pos], hash) { |
| 2103 | r = func(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2104 | if (r < 0) |
| 2105 | return r; |
| 2106 | result += r; |
| 2107 | } |
| 2108 | } |
| 2109 | |
| 2110 | return result; |
| 2111 | } |
| 2112 | |
| 2113 | |
| 2114 | /* Free all nodes associated with a file. */ |
| 2115 | static int |
| 2116 | jffs_free_node_list(struct jffs_file *f) |
| 2117 | { |
| 2118 | struct jffs_node *node; |
| 2119 | struct jffs_node *p; |
| 2120 | |
| 2121 | D3(printk("jffs_free_node_list(): f #%u, \"%s\"\n", |
| 2122 | f->ino, (f->name ? f->name : ""))); |
| 2123 | node = f->version_head; |
| 2124 | while (node) { |
| 2125 | p = node; |
| 2126 | node = node->version_next; |
| 2127 | jffs_free_node(p); |
| 2128 | DJM(no_jffs_node--); |
| 2129 | } |
| 2130 | return 0; |
| 2131 | } |
| 2132 | |
| 2133 | |
| 2134 | /* Free a file and its name. */ |
| 2135 | static int |
| 2136 | jffs_free_file(struct jffs_file *f) |
| 2137 | { |
| 2138 | D3(printk("jffs_free_file: f #%u, \"%s\"\n", |
| 2139 | f->ino, (f->name ? f->name : ""))); |
| 2140 | |
| 2141 | if (f->name) { |
| 2142 | kfree(f->name); |
| 2143 | DJM(no_name--); |
| 2144 | } |
| 2145 | kfree(f); |
| 2146 | no_jffs_file--; |
| 2147 | return 0; |
| 2148 | } |
| 2149 | |
| 2150 | static long |
| 2151 | jffs_get_file_count(void) |
| 2152 | { |
| 2153 | return no_jffs_file; |
| 2154 | } |
| 2155 | |
| 2156 | /* See if a file is deleted. If so, mark that file's nodes as obsolete. */ |
| 2157 | int |
| 2158 | jffs_possibly_delete_file(struct jffs_file *f) |
| 2159 | { |
| 2160 | struct jffs_node *n; |
| 2161 | |
| 2162 | D3(printk("jffs_possibly_delete_file(): ino: %u\n", |
| 2163 | f->ino)); |
| 2164 | |
| 2165 | ASSERT(if (!f) { |
| 2166 | printk(KERN_ERR "jffs_possibly_delete_file(): f == NULL\n"); |
| 2167 | return -1; |
| 2168 | }); |
| 2169 | |
| 2170 | if (f->deleted) { |
| 2171 | /* First try to remove all older versions. Commence with |
| 2172 | the oldest node. */ |
| 2173 | for (n = f->version_head; n; n = n->version_next) { |
| 2174 | if (!n->fm) { |
| 2175 | continue; |
| 2176 | } |
| 2177 | if (jffs_fmfree(f->c->fmc, n->fm, n) < 0) { |
| 2178 | break; |
| 2179 | } |
| 2180 | } |
| 2181 | /* Unlink the file from the filesystem. */ |
| 2182 | if (!f->c->building_fs) { |
| 2183 | jffs_unlink_file_from_tree(f); |
| 2184 | } |
| 2185 | jffs_unlink_file_from_hash(f); |
| 2186 | jffs_free_node_list(f); |
| 2187 | jffs_free_file(f); |
| 2188 | } |
| 2189 | return 0; |
| 2190 | } |
| 2191 | |
| 2192 | |
| 2193 | /* Used in conjunction with jffs_foreach_file() to count the number |
| 2194 | of files in the file system. */ |
| 2195 | int |
| 2196 | jffs_file_count(struct jffs_file *f) |
| 2197 | { |
| 2198 | return 1; |
| 2199 | } |
| 2200 | |
| 2201 | |
| 2202 | /* Build up a file's range list from scratch by going through the |
| 2203 | version list. */ |
| 2204 | static int |
| 2205 | jffs_build_file(struct jffs_file *f) |
| 2206 | { |
| 2207 | struct jffs_node *n; |
| 2208 | |
| 2209 | D3(printk("jffs_build_file(): ino: %u, name: \"%s\"\n", |
| 2210 | f->ino, (f->name ? f->name : ""))); |
| 2211 | |
| 2212 | for (n = f->version_head; n; n = n->version_next) { |
| 2213 | jffs_update_file(f, n); |
| 2214 | } |
| 2215 | return 0; |
| 2216 | } |
| 2217 | |
| 2218 | |
| 2219 | /* Remove an amount of data from a file. If this amount of data is |
| 2220 | zero, that could mean that a node should be split in two parts. |
| 2221 | We remove or change the appropriate nodes in the lists. |
| 2222 | |
| 2223 | Starting offset of area to be removed is node->data_offset, |
| 2224 | and the length of the area is in node->removed_size. */ |
| 2225 | static int |
| 2226 | jffs_delete_data(struct jffs_file *f, struct jffs_node *node) |
| 2227 | { |
| 2228 | struct jffs_node *n; |
| 2229 | __u32 offset = node->data_offset; |
| 2230 | __u32 remove_size = node->removed_size; |
| 2231 | |
| 2232 | D3(printk("jffs_delete_data(): offset = %u, remove_size = %u\n", |
| 2233 | offset, remove_size)); |
| 2234 | |
| 2235 | if (remove_size == 0 |
| 2236 | && f->range_tail |
| 2237 | && f->range_tail->data_offset + f->range_tail->data_size |
| 2238 | == offset) { |
| 2239 | /* A simple append; nothing to remove or no node to split. */ |
| 2240 | return 0; |
| 2241 | } |
| 2242 | |
| 2243 | /* Find the node where we should begin the removal. */ |
| 2244 | for (n = f->range_head; n; n = n->range_next) { |
| 2245 | if (n->data_offset + n->data_size > offset) { |
| 2246 | break; |
| 2247 | } |
| 2248 | } |
| 2249 | if (!n) { |
| 2250 | /* If there's no data in the file there's no data to |
| 2251 | remove either. */ |
| 2252 | return 0; |
| 2253 | } |
| 2254 | |
| 2255 | if (n->data_offset > offset) { |
| 2256 | /* XXX: Not implemented yet. */ |
| 2257 | printk(KERN_WARNING "JFFS: An unexpected situation " |
| 2258 | "occurred in jffs_delete_data.\n"); |
| 2259 | } |
| 2260 | else if (n->data_offset < offset) { |
| 2261 | /* See if the node has to be split into two parts. */ |
| 2262 | if (n->data_offset + n->data_size > offset + remove_size) { |
| 2263 | /* Do the split. */ |
| 2264 | struct jffs_node *new_node; |
| 2265 | D3(printk("jffs_delete_data(): Split node with " |
| 2266 | "version number %u.\n", n->version)); |
| 2267 | |
| 2268 | if (!(new_node = jffs_alloc_node())) { |
| 2269 | D(printk("jffs_delete_data(): -ENOMEM\n")); |
| 2270 | return -ENOMEM; |
| 2271 | } |
| 2272 | DJM(no_jffs_node++); |
| 2273 | |
| 2274 | new_node->ino = n->ino; |
| 2275 | new_node->version = n->version; |
| 2276 | new_node->data_offset = offset; |
| 2277 | new_node->data_size = n->data_size - (remove_size + (offset - n->data_offset)); |
| 2278 | new_node->fm_offset = n->fm_offset + (remove_size + (offset - n->data_offset)); |
| 2279 | new_node->name_size = n->name_size; |
| 2280 | new_node->fm = n->fm; |
| 2281 | new_node->version_prev = n; |
| 2282 | new_node->version_next = n->version_next; |
| 2283 | if (new_node->version_next) { |
| 2284 | new_node->version_next->version_prev |
| 2285 | = new_node; |
| 2286 | } |
| 2287 | else { |
| 2288 | f->version_tail = new_node; |
| 2289 | } |
| 2290 | n->version_next = new_node; |
| 2291 | new_node->range_prev = n; |
| 2292 | new_node->range_next = n->range_next; |
| 2293 | if (new_node->range_next) { |
| 2294 | new_node->range_next->range_prev = new_node; |
| 2295 | } |
| 2296 | else { |
| 2297 | f->range_tail = new_node; |
| 2298 | } |
| 2299 | /* A very interesting can of worms. */ |
| 2300 | n->range_next = new_node; |
| 2301 | n->data_size = offset - n->data_offset; |
| 2302 | if (new_node->fm) |
| 2303 | jffs_add_node(new_node); |
| 2304 | else { |
| 2305 | D1(printk(KERN_WARNING "jffs_delete_data(): Splitting an empty node (file hold).\n!")); |
| 2306 | D1(printk(KERN_WARNING "FIXME: Did dwmw2 do the right thing here?\n")); |
| 2307 | } |
| 2308 | n = new_node->range_next; |
| 2309 | remove_size = 0; |
| 2310 | } |
| 2311 | else { |
| 2312 | /* No. No need to split the node. Just remove |
| 2313 | the end of the node. */ |
| 2314 | int r = min(n->data_offset + n->data_size |
| 2315 | - offset, remove_size); |
| 2316 | n->data_size -= r; |
| 2317 | remove_size -= r; |
| 2318 | n = n->range_next; |
| 2319 | } |
| 2320 | } |
| 2321 | |
| 2322 | /* Remove as many nodes as necessary. */ |
| 2323 | while (n && remove_size) { |
| 2324 | if (n->data_size <= remove_size) { |
| 2325 | struct jffs_node *p = n; |
| 2326 | remove_size -= n->data_size; |
| 2327 | n = n->range_next; |
| 2328 | D3(printk("jffs_delete_data(): Removing node: " |
| 2329 | "ino: %u, version: %u%s\n", |
| 2330 | p->ino, p->version, |
| 2331 | (p->fm ? "" : " (virtual)"))); |
| 2332 | if (p->fm) { |
| 2333 | jffs_fmfree(f->c->fmc, p->fm, p); |
| 2334 | } |
| 2335 | jffs_unlink_node_from_range_list(f, p); |
| 2336 | jffs_unlink_node_from_version_list(f, p); |
| 2337 | jffs_free_node(p); |
| 2338 | DJM(no_jffs_node--); |
| 2339 | } |
| 2340 | else { |
| 2341 | n->data_size -= remove_size; |
| 2342 | n->fm_offset += remove_size; |
| 2343 | n->data_offset -= (node->removed_size - remove_size); |
| 2344 | n = n->range_next; |
| 2345 | break; |
| 2346 | } |
| 2347 | } |
| 2348 | |
| 2349 | /* Adjust the following nodes' information about offsets etc. */ |
| 2350 | while (n && node->removed_size) { |
| 2351 | n->data_offset -= node->removed_size; |
| 2352 | n = n->range_next; |
| 2353 | } |
| 2354 | |
| 2355 | if (node->removed_size > (f->size - node->data_offset)) { |
| 2356 | /* It's possible that the removed_size is in fact |
| 2357 | * greater than the amount of data we actually thought |
| 2358 | * were present in the first place - some of the nodes |
| 2359 | * which this node originally obsoleted may already have |
| 2360 | * been deleted from the flash by subsequent garbage |
| 2361 | * collection. |
| 2362 | * |
| 2363 | * If this is the case, don't let f->size go negative. |
| 2364 | * Bad things would happen :) |
| 2365 | */ |
| 2366 | f->size = node->data_offset; |
| 2367 | } else { |
| 2368 | f->size -= node->removed_size; |
| 2369 | } |
| 2370 | D3(printk("jffs_delete_data(): f->size = %d\n", f->size)); |
| 2371 | return 0; |
| 2372 | } /* jffs_delete_data() */ |
| 2373 | |
| 2374 | |
| 2375 | /* Insert some data into a file. Prior to the call to this function, |
| 2376 | jffs_delete_data should be called. */ |
| 2377 | static int |
| 2378 | jffs_insert_data(struct jffs_file *f, struct jffs_node *node) |
| 2379 | { |
| 2380 | D3(printk("jffs_insert_data(): node->data_offset = %u, " |
| 2381 | "node->data_size = %u, f->size = %u\n", |
| 2382 | node->data_offset, node->data_size, f->size)); |
| 2383 | |
| 2384 | /* Find the position where we should insert data. */ |
| 2385 | retry: |
| 2386 | if (node->data_offset == f->size) { |
| 2387 | /* A simple append. This is the most common operation. */ |
| 2388 | node->range_next = NULL; |
| 2389 | node->range_prev = f->range_tail; |
| 2390 | if (node->range_prev) { |
| 2391 | node->range_prev->range_next = node; |
| 2392 | } |
| 2393 | f->range_tail = node; |
| 2394 | f->size += node->data_size; |
| 2395 | if (!f->range_head) { |
| 2396 | f->range_head = node; |
| 2397 | } |
| 2398 | } |
| 2399 | else if (node->data_offset < f->size) { |
| 2400 | /* Trying to insert data into the middle of the file. This |
| 2401 | means no problem because jffs_delete_data() has already |
| 2402 | prepared the range list for us. */ |
| 2403 | struct jffs_node *n; |
| 2404 | |
| 2405 | /* Find the correct place for the insertion and then insert |
| 2406 | the node. */ |
| 2407 | for (n = f->range_head; n; n = n->range_next) { |
| 2408 | D2(printk("Cool stuff's happening!\n")); |
| 2409 | |
| 2410 | if (n->data_offset == node->data_offset) { |
| 2411 | node->range_prev = n->range_prev; |
| 2412 | if (node->range_prev) { |
| 2413 | node->range_prev->range_next = node; |
| 2414 | } |
| 2415 | else { |
| 2416 | f->range_head = node; |
| 2417 | } |
| 2418 | node->range_next = n; |
| 2419 | n->range_prev = node; |
| 2420 | break; |
| 2421 | } |
| 2422 | ASSERT(else if (n->data_offset + n->data_size > |
| 2423 | node->data_offset) { |
| 2424 | printk(KERN_ERR "jffs_insert_data(): " |
| 2425 | "Couldn't find a place to insert " |
| 2426 | "the data!\n"); |
| 2427 | return -1; |
| 2428 | }); |
| 2429 | } |
| 2430 | |
| 2431 | /* Adjust later nodes' offsets etc. */ |
| 2432 | n = node->range_next; |
| 2433 | while (n) { |
| 2434 | n->data_offset += node->data_size; |
| 2435 | n = n->range_next; |
| 2436 | } |
| 2437 | f->size += node->data_size; |
| 2438 | } |
| 2439 | else if (node->data_offset > f->size) { |
| 2440 | /* Okay. This is tricky. This means that we want to insert |
| 2441 | data at a place that is beyond the limits of the file as |
| 2442 | it is constructed right now. This is actually a common |
| 2443 | event that for instance could occur during the mounting |
| 2444 | of the file system if a large file have been truncated, |
| 2445 | rewritten and then only partially garbage collected. */ |
| 2446 | |
| 2447 | struct jffs_node *n; |
| 2448 | |
| 2449 | /* We need a place holder for the data that is missing in |
| 2450 | front of this insertion. This "virtual node" will not |
| 2451 | be associated with any space on the flash device. */ |
| 2452 | struct jffs_node *virtual_node; |
| 2453 | if (!(virtual_node = jffs_alloc_node())) { |
| 2454 | return -ENOMEM; |
| 2455 | } |
| 2456 | |
| 2457 | D(printk("jffs_insert_data: Inserting a virtual node.\n")); |
| 2458 | D(printk(" node->data_offset = %u\n", node->data_offset)); |
| 2459 | D(printk(" f->size = %u\n", f->size)); |
| 2460 | |
| 2461 | virtual_node->ino = node->ino; |
| 2462 | virtual_node->version = node->version; |
| 2463 | virtual_node->removed_size = 0; |
| 2464 | virtual_node->fm_offset = 0; |
| 2465 | virtual_node->name_size = 0; |
| 2466 | virtual_node->fm = NULL; /* This is a virtual data holder. */ |
| 2467 | virtual_node->version_prev = NULL; |
| 2468 | virtual_node->version_next = NULL; |
| 2469 | virtual_node->range_next = NULL; |
| 2470 | |
| 2471 | /* Are there any data at all in the file yet? */ |
| 2472 | if (f->range_head) { |
| 2473 | virtual_node->data_offset |
| 2474 | = f->range_tail->data_offset |
| 2475 | + f->range_tail->data_size; |
| 2476 | virtual_node->data_size |
| 2477 | = node->data_offset - virtual_node->data_offset; |
| 2478 | virtual_node->range_prev = f->range_tail; |
| 2479 | f->range_tail->range_next = virtual_node; |
| 2480 | } |
| 2481 | else { |
| 2482 | virtual_node->data_offset = 0; |
| 2483 | virtual_node->data_size = node->data_offset; |
| 2484 | virtual_node->range_prev = NULL; |
| 2485 | f->range_head = virtual_node; |
| 2486 | } |
| 2487 | |
| 2488 | f->range_tail = virtual_node; |
| 2489 | f->size += virtual_node->data_size; |
| 2490 | |
| 2491 | /* Insert this virtual node in the version list as well. */ |
| 2492 | for (n = f->version_head; n ; n = n->version_next) { |
| 2493 | if (n->version == virtual_node->version) { |
| 2494 | virtual_node->version_prev = n->version_prev; |
| 2495 | n->version_prev = virtual_node; |
| 2496 | if (virtual_node->version_prev) { |
| 2497 | virtual_node->version_prev |
| 2498 | ->version_next = virtual_node; |
| 2499 | } |
| 2500 | else { |
| 2501 | f->version_head = virtual_node; |
| 2502 | } |
| 2503 | virtual_node->version_next = n; |
| 2504 | break; |
| 2505 | } |
| 2506 | } |
| 2507 | |
| 2508 | D(jffs_print_node(virtual_node)); |
| 2509 | |
| 2510 | /* Make a new try to insert the node. */ |
| 2511 | goto retry; |
| 2512 | } |
| 2513 | |
| 2514 | D3(printk("jffs_insert_data(): f->size = %d\n", f->size)); |
| 2515 | return 0; |
| 2516 | } |
| 2517 | |
| 2518 | |
| 2519 | /* A new node (with data) has been added to the file and now the range |
| 2520 | list has to be modified. */ |
| 2521 | static int |
| 2522 | jffs_update_file(struct jffs_file *f, struct jffs_node *node) |
| 2523 | { |
| 2524 | int err; |
| 2525 | |
| 2526 | D3(printk("jffs_update_file(): ino: %u, version: %u\n", |
| 2527 | f->ino, node->version)); |
| 2528 | |
| 2529 | if (node->data_size == 0) { |
| 2530 | if (node->removed_size == 0) { |
| 2531 | /* data_offset == X */ |
| 2532 | /* data_size == 0 */ |
| 2533 | /* remove_size == 0 */ |
| 2534 | } |
| 2535 | else { |
| 2536 | /* data_offset == X */ |
| 2537 | /* data_size == 0 */ |
| 2538 | /* remove_size != 0 */ |
| 2539 | if ((err = jffs_delete_data(f, node)) < 0) { |
| 2540 | return err; |
| 2541 | } |
| 2542 | } |
| 2543 | } |
| 2544 | else { |
| 2545 | /* data_offset == X */ |
| 2546 | /* data_size != 0 */ |
| 2547 | /* remove_size == Y */ |
| 2548 | if ((err = jffs_delete_data(f, node)) < 0) { |
| 2549 | return err; |
| 2550 | } |
| 2551 | if ((err = jffs_insert_data(f, node)) < 0) { |
| 2552 | return err; |
| 2553 | } |
| 2554 | } |
| 2555 | return 0; |
| 2556 | } |
| 2557 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2558 | /* Print the contents of a file. */ |
| 2559 | #if 0 |
| 2560 | int |
| 2561 | jffs_print_file(struct jffs_file *f) |
| 2562 | { |
| 2563 | D(int i); |
| 2564 | D(printk("jffs_file: 0x%p\n", f)); |
| 2565 | D(printk("{\n")); |
| 2566 | D(printk(" 0x%08x, /* ino */\n", f->ino)); |
| 2567 | D(printk(" 0x%08x, /* pino */\n", f->pino)); |
| 2568 | D(printk(" 0x%08x, /* mode */\n", f->mode)); |
| 2569 | D(printk(" 0x%04x, /* uid */\n", f->uid)); |
| 2570 | D(printk(" 0x%04x, /* gid */\n", f->gid)); |
| 2571 | D(printk(" 0x%08x, /* atime */\n", f->atime)); |
| 2572 | D(printk(" 0x%08x, /* mtime */\n", f->mtime)); |
| 2573 | D(printk(" 0x%08x, /* ctime */\n", f->ctime)); |
| 2574 | D(printk(" 0x%02x, /* nsize */\n", f->nsize)); |
| 2575 | D(printk(" 0x%02x, /* nlink */\n", f->nlink)); |
| 2576 | D(printk(" 0x%02x, /* deleted */\n", f->deleted)); |
| 2577 | D(printk(" \"%s\", ", (f->name ? f->name : ""))); |
| 2578 | D(for (i = strlen(f->name ? f->name : ""); i < 8; ++i) { |
| 2579 | printk(" "); |
| 2580 | }); |
| 2581 | D(printk("/* name */\n")); |
| 2582 | D(printk(" 0x%08x, /* size */\n", f->size)); |
| 2583 | D(printk(" 0x%08x, /* highest_version */\n", |
| 2584 | f->highest_version)); |
| 2585 | D(printk(" 0x%p, /* c */\n", f->c)); |
| 2586 | D(printk(" 0x%p, /* parent */\n", f->parent)); |
| 2587 | D(printk(" 0x%p, /* children */\n", f->children)); |
| 2588 | D(printk(" 0x%p, /* sibling_prev */\n", f->sibling_prev)); |
| 2589 | D(printk(" 0x%p, /* sibling_next */\n", f->sibling_next)); |
| 2590 | D(printk(" 0x%p, /* hash_prev */\n", f->hash.prev)); |
| 2591 | D(printk(" 0x%p, /* hash_next */\n", f->hash.next)); |
| 2592 | D(printk(" 0x%p, /* range_head */\n", f->range_head)); |
| 2593 | D(printk(" 0x%p, /* range_tail */\n", f->range_tail)); |
| 2594 | D(printk(" 0x%p, /* version_head */\n", f->version_head)); |
| 2595 | D(printk(" 0x%p, /* version_tail */\n", f->version_tail)); |
| 2596 | D(printk("}\n")); |
| 2597 | return 0; |
| 2598 | } |
| 2599 | #endif /* 0 */ |
| 2600 | |
| 2601 | void |
| 2602 | jffs_print_hash_table(struct jffs_control *c) |
| 2603 | { |
| 2604 | int i; |
| 2605 | |
| 2606 | printk("JFFS: Dumping the file system's hash table...\n"); |
| 2607 | for (i = 0; i < c->hash_len; i++) { |
Domen Puncer | 216d81b | 2005-09-10 00:27:05 -0700 | [diff] [blame] | 2608 | struct jffs_file *f; |
| 2609 | list_for_each_entry(f, &c->hash[i], hash) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2610 | printk("*** c->hash[%u]: \"%s\" " |
| 2611 | "(ino: %u, pino: %u)\n", |
| 2612 | i, (f->name ? f->name : ""), |
| 2613 | f->ino, f->pino); |
| 2614 | } |
| 2615 | } |
| 2616 | } |
| 2617 | |
| 2618 | |
| 2619 | void |
| 2620 | jffs_print_tree(struct jffs_file *first_file, int indent) |
| 2621 | { |
| 2622 | struct jffs_file *f; |
| 2623 | char *space; |
| 2624 | int dir; |
| 2625 | |
| 2626 | if (!first_file) { |
| 2627 | return; |
| 2628 | } |
| 2629 | |
| 2630 | if (!(space = (char *) kmalloc(indent + 1, GFP_KERNEL))) { |
| 2631 | printk("jffs_print_tree(): Out of memory!\n"); |
| 2632 | return; |
| 2633 | } |
| 2634 | |
| 2635 | memset(space, ' ', indent); |
| 2636 | space[indent] = '\0'; |
| 2637 | |
| 2638 | for (f = first_file; f; f = f->sibling_next) { |
| 2639 | dir = S_ISDIR(f->mode); |
| 2640 | printk("%s%s%s (ino: %u, highest_version: %u, size: %u)\n", |
| 2641 | space, (f->name ? f->name : ""), (dir ? "/" : ""), |
| 2642 | f->ino, f->highest_version, f->size); |
| 2643 | if (dir) { |
| 2644 | jffs_print_tree(f->children, indent + 2); |
| 2645 | } |
| 2646 | } |
| 2647 | |
| 2648 | kfree(space); |
| 2649 | } |
| 2650 | |
| 2651 | |
| 2652 | #if defined(JFFS_MEMORY_DEBUG) && JFFS_MEMORY_DEBUG |
| 2653 | void |
| 2654 | jffs_print_memory_allocation_statistics(void) |
| 2655 | { |
| 2656 | static long printout; |
| 2657 | printk("________ Memory printout #%ld ________\n", ++printout); |
| 2658 | printk("no_jffs_file = %ld\n", no_jffs_file); |
| 2659 | printk("no_jffs_node = %ld\n", no_jffs_node); |
| 2660 | printk("no_jffs_control = %ld\n", no_jffs_control); |
| 2661 | printk("no_jffs_raw_inode = %ld\n", no_jffs_raw_inode); |
| 2662 | printk("no_jffs_node_ref = %ld\n", no_jffs_node_ref); |
| 2663 | printk("no_jffs_fm = %ld\n", no_jffs_fm); |
| 2664 | printk("no_jffs_fmcontrol = %ld\n", no_jffs_fmcontrol); |
| 2665 | printk("no_hash = %ld\n", no_hash); |
| 2666 | printk("no_name = %ld\n", no_name); |
| 2667 | printk("\n"); |
| 2668 | } |
| 2669 | #endif |
| 2670 | |
| 2671 | |
| 2672 | /* Rewrite `size' bytes, and begin at `node'. */ |
| 2673 | static int |
| 2674 | jffs_rewrite_data(struct jffs_file *f, struct jffs_node *node, __u32 size) |
| 2675 | { |
| 2676 | struct jffs_control *c = f->c; |
| 2677 | struct jffs_fmcontrol *fmc = c->fmc; |
| 2678 | struct jffs_raw_inode raw_inode; |
| 2679 | struct jffs_node *new_node; |
| 2680 | struct jffs_fm *fm; |
| 2681 | __u32 pos; |
| 2682 | __u32 pos_dchksum; |
| 2683 | __u32 total_name_size; |
| 2684 | __u32 total_data_size; |
| 2685 | __u32 total_size; |
| 2686 | int err; |
| 2687 | |
| 2688 | D1(printk("***jffs_rewrite_data(): node: %u, name: \"%s\", size: %u\n", |
| 2689 | f->ino, (f->name ? f->name : "(null)"), size)); |
| 2690 | |
| 2691 | /* Create and initialize the new node. */ |
| 2692 | if (!(new_node = jffs_alloc_node())) { |
| 2693 | D(printk("jffs_rewrite_data(): " |
| 2694 | "Failed to allocate node.\n")); |
| 2695 | return -ENOMEM; |
| 2696 | } |
| 2697 | DJM(no_jffs_node++); |
| 2698 | new_node->data_offset = node->data_offset; |
| 2699 | new_node->removed_size = size; |
| 2700 | total_name_size = JFFS_PAD(f->nsize); |
| 2701 | total_data_size = JFFS_PAD(size); |
| 2702 | total_size = sizeof(struct jffs_raw_inode) |
| 2703 | + total_name_size + total_data_size; |
| 2704 | new_node->fm_offset = sizeof(struct jffs_raw_inode) |
| 2705 | + total_name_size; |
| 2706 | |
| 2707 | retry: |
| 2708 | jffs_fm_write_lock(fmc); |
| 2709 | err = 0; |
| 2710 | |
| 2711 | if ((err = jffs_fmalloc(fmc, total_size, new_node, &fm)) < 0) { |
| 2712 | DJM(no_jffs_node--); |
| 2713 | jffs_fm_write_unlock(fmc); |
| 2714 | D(printk("jffs_rewrite_data(): Failed to allocate fm.\n")); |
| 2715 | jffs_free_node(new_node); |
| 2716 | return err; |
| 2717 | } |
| 2718 | else if (!fm->nodes) { |
| 2719 | /* The jffs_fm struct that we got is not big enough. */ |
| 2720 | /* This should never happen, because we deal with this case |
| 2721 | in jffs_garbage_collect_next().*/ |
| 2722 | printk(KERN_WARNING "jffs_rewrite_data(): Allocated node is too small (%d bytes of %d)\n", fm->size, total_size); |
| 2723 | if ((err = jffs_write_dummy_node(c, fm)) < 0) { |
| 2724 | D(printk("jffs_rewrite_data(): " |
| 2725 | "jffs_write_dummy_node() Failed!\n")); |
| 2726 | } else { |
| 2727 | err = -ENOSPC; |
| 2728 | } |
| 2729 | DJM(no_jffs_fm--); |
| 2730 | jffs_fm_write_unlock(fmc); |
| 2731 | kfree(fm); |
| 2732 | |
| 2733 | return err; |
| 2734 | } |
| 2735 | new_node->fm = fm; |
| 2736 | |
| 2737 | /* Initialize the raw inode. */ |
| 2738 | raw_inode.magic = JFFS_MAGIC_BITMASK; |
| 2739 | raw_inode.ino = f->ino; |
| 2740 | raw_inode.pino = f->pino; |
| 2741 | raw_inode.version = f->highest_version + 1; |
| 2742 | raw_inode.mode = f->mode; |
| 2743 | raw_inode.uid = f->uid; |
| 2744 | raw_inode.gid = f->gid; |
| 2745 | raw_inode.atime = f->atime; |
| 2746 | raw_inode.mtime = f->mtime; |
| 2747 | raw_inode.ctime = f->ctime; |
| 2748 | raw_inode.offset = node->data_offset; |
| 2749 | raw_inode.dsize = size; |
| 2750 | raw_inode.rsize = size; |
| 2751 | raw_inode.nsize = f->nsize; |
| 2752 | raw_inode.nlink = f->nlink; |
| 2753 | raw_inode.spare = 0; |
| 2754 | raw_inode.rename = 0; |
| 2755 | raw_inode.deleted = f->deleted; |
| 2756 | raw_inode.accurate = 0xff; |
| 2757 | raw_inode.dchksum = 0; |
| 2758 | raw_inode.nchksum = 0; |
| 2759 | |
| 2760 | pos = new_node->fm->offset; |
| 2761 | pos_dchksum = pos +JFFS_RAW_INODE_DCHKSUM_OFFSET; |
| 2762 | |
| 2763 | D3(printk("jffs_rewrite_data(): Writing this raw inode " |
| 2764 | "to pos 0x%ul.\n", pos)); |
| 2765 | D3(jffs_print_raw_inode(&raw_inode)); |
| 2766 | |
| 2767 | if ((err = flash_safe_write(fmc->mtd, pos, |
| 2768 | (u_char *) &raw_inode, |
| 2769 | sizeof(struct jffs_raw_inode) |
| 2770 | - sizeof(__u32) |
| 2771 | - sizeof(__u16) - sizeof(__u16))) < 0) { |
| 2772 | jffs_fmfree_partly(fmc, fm, |
| 2773 | total_name_size + total_data_size); |
| 2774 | jffs_fm_write_unlock(fmc); |
| 2775 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Write error during " |
| 2776 | "rewrite. (raw inode)\n"); |
| 2777 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Now retrying " |
| 2778 | "rewrite. (raw inode)\n"); |
| 2779 | goto retry; |
| 2780 | } |
| 2781 | pos += sizeof(struct jffs_raw_inode); |
| 2782 | |
| 2783 | /* Write the name to the flash memory. */ |
| 2784 | if (f->nsize) { |
| 2785 | D3(printk("jffs_rewrite_data(): Writing name \"%s\" to " |
| 2786 | "pos 0x%ul.\n", f->name, (unsigned int) pos)); |
| 2787 | if ((err = flash_safe_write(fmc->mtd, pos, |
| 2788 | (u_char *)f->name, |
| 2789 | f->nsize)) < 0) { |
| 2790 | jffs_fmfree_partly(fmc, fm, total_data_size); |
| 2791 | jffs_fm_write_unlock(fmc); |
| 2792 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Write " |
| 2793 | "error during rewrite. (name)\n"); |
| 2794 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Now retrying " |
| 2795 | "rewrite. (name)\n"); |
| 2796 | goto retry; |
| 2797 | } |
| 2798 | pos += total_name_size; |
| 2799 | raw_inode.nchksum = jffs_checksum(f->name, f->nsize); |
| 2800 | } |
| 2801 | |
| 2802 | /* Write the data. */ |
| 2803 | if (size) { |
| 2804 | int r; |
| 2805 | unsigned char *page; |
| 2806 | __u32 offset = node->data_offset; |
| 2807 | |
| 2808 | if (!(page = (unsigned char *)__get_free_page(GFP_KERNEL))) { |
| 2809 | jffs_fmfree_partly(fmc, fm, 0); |
| 2810 | return -1; |
| 2811 | } |
| 2812 | |
| 2813 | while (size) { |
| 2814 | __u32 s = min(size, (__u32)PAGE_SIZE); |
| 2815 | if ((r = jffs_read_data(f, (char *)page, |
| 2816 | offset, s)) < s) { |
| 2817 | free_page((unsigned long)page); |
| 2818 | jffs_fmfree_partly(fmc, fm, 0); |
| 2819 | jffs_fm_write_unlock(fmc); |
| 2820 | printk(KERN_ERR "JFFS: jffs_rewrite_data: " |
| 2821 | "jffs_read_data() " |
| 2822 | "failed! (r = %d)\n", r); |
| 2823 | return -1; |
| 2824 | } |
| 2825 | if ((err = flash_safe_write(fmc->mtd, |
| 2826 | pos, page, r)) < 0) { |
| 2827 | free_page((unsigned long)page); |
| 2828 | jffs_fmfree_partly(fmc, fm, 0); |
| 2829 | jffs_fm_write_unlock(fmc); |
| 2830 | printk(KERN_ERR "JFFS: jffs_rewrite_data: " |
| 2831 | "Write error during rewrite. " |
| 2832 | "(data)\n"); |
| 2833 | goto retry; |
| 2834 | } |
| 2835 | pos += r; |
| 2836 | size -= r; |
| 2837 | offset += r; |
| 2838 | raw_inode.dchksum += jffs_checksum(page, r); |
| 2839 | } |
| 2840 | |
| 2841 | free_page((unsigned long)page); |
| 2842 | } |
| 2843 | |
| 2844 | raw_inode.accurate = 0; |
| 2845 | raw_inode.chksum = jffs_checksum(&raw_inode, |
| 2846 | sizeof(struct jffs_raw_inode) |
| 2847 | - sizeof(__u16)); |
| 2848 | |
| 2849 | /* Add the checksum. */ |
| 2850 | if ((err |
| 2851 | = flash_safe_write(fmc->mtd, pos_dchksum, |
| 2852 | &((u_char *) |
| 2853 | &raw_inode)[JFFS_RAW_INODE_DCHKSUM_OFFSET], |
| 2854 | sizeof(__u32) + sizeof(__u16) |
| 2855 | + sizeof(__u16))) < 0) { |
| 2856 | jffs_fmfree_partly(fmc, fm, 0); |
| 2857 | jffs_fm_write_unlock(fmc); |
| 2858 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Write error during " |
| 2859 | "rewrite. (checksum)\n"); |
| 2860 | goto retry; |
| 2861 | } |
| 2862 | |
| 2863 | /* Now make the file system aware of the newly written node. */ |
| 2864 | jffs_insert_node(c, f, &raw_inode, f->name, new_node); |
| 2865 | jffs_fm_write_unlock(fmc); |
| 2866 | |
| 2867 | D3(printk("jffs_rewrite_data(): Leaving...\n")); |
| 2868 | return 0; |
| 2869 | } /* jffs_rewrite_data() */ |
| 2870 | |
| 2871 | |
| 2872 | /* jffs_garbage_collect_next implements one step in the garbage collect |
| 2873 | process and is often called multiple times at each occasion of a |
| 2874 | garbage collect. */ |
| 2875 | |
| 2876 | static int |
| 2877 | jffs_garbage_collect_next(struct jffs_control *c) |
| 2878 | { |
| 2879 | struct jffs_fmcontrol *fmc = c->fmc; |
| 2880 | struct jffs_node *node; |
| 2881 | struct jffs_file *f; |
| 2882 | int err = 0; |
| 2883 | __u32 size; |
| 2884 | __u32 data_size; |
| 2885 | __u32 total_name_size; |
| 2886 | __u32 extra_available; |
| 2887 | __u32 space_needed; |
| 2888 | __u32 free_chunk_size1 = jffs_free_size1(fmc); |
| 2889 | D2(__u32 free_chunk_size2 = jffs_free_size2(fmc)); |
| 2890 | |
| 2891 | /* Get the oldest node in the flash. */ |
| 2892 | node = jffs_get_oldest_node(fmc); |
| 2893 | ASSERT(if (!node) { |
| 2894 | printk(KERN_ERR "JFFS: jffs_garbage_collect_next: " |
| 2895 | "No oldest node found!\n"); |
| 2896 | err = -1; |
| 2897 | goto jffs_garbage_collect_next_end; |
| 2898 | |
| 2899 | |
| 2900 | }); |
| 2901 | |
| 2902 | /* Find its corresponding file too. */ |
| 2903 | f = jffs_find_file(c, node->ino); |
| 2904 | |
| 2905 | if (!f) { |
| 2906 | printk (KERN_ERR "JFFS: jffs_garbage_collect_next: " |
| 2907 | "No file to garbage collect! " |
| 2908 | "(ino = 0x%08x)\n", node->ino); |
| 2909 | /* FIXME: Free the offending node and recover. */ |
| 2910 | err = -1; |
| 2911 | goto jffs_garbage_collect_next_end; |
| 2912 | } |
| 2913 | |
| 2914 | /* We always write out the name. Theoretically, we don't need |
| 2915 | to, but for now it's easier - because otherwise we'd have |
| 2916 | to keep track of how many times the current name exists on |
| 2917 | the flash and make sure it never reaches zero. |
| 2918 | |
| 2919 | The current approach means that would be possible to cause |
| 2920 | the GC to end up eating its tail by writing lots of nodes |
| 2921 | with no name for it to garbage-collect. Hence the change in |
| 2922 | inode.c to write names with _every_ node. |
| 2923 | |
| 2924 | It sucks, but it _should_ work. |
| 2925 | */ |
| 2926 | total_name_size = JFFS_PAD(f->nsize); |
| 2927 | |
| 2928 | D1(printk("jffs_garbage_collect_next(): \"%s\", " |
| 2929 | "ino: %u, version: %u, location 0x%x, dsize %u\n", |
| 2930 | (f->name ? f->name : ""), node->ino, node->version, |
| 2931 | node->fm->offset, node->data_size)); |
| 2932 | |
| 2933 | /* Compute how many data it's possible to rewrite at the moment. */ |
| 2934 | data_size = f->size - node->data_offset; |
| 2935 | |
| 2936 | /* And from that, the total size of the chunk we want to write */ |
| 2937 | size = sizeof(struct jffs_raw_inode) + total_name_size |
| 2938 | + data_size + JFFS_GET_PAD_BYTES(data_size); |
| 2939 | |
| 2940 | /* If that's more than max_chunk_size, reduce it accordingly */ |
| 2941 | if (size > fmc->max_chunk_size) { |
| 2942 | size = fmc->max_chunk_size; |
| 2943 | data_size = size - sizeof(struct jffs_raw_inode) |
| 2944 | - total_name_size; |
| 2945 | } |
| 2946 | |
| 2947 | /* If we're asking to take up more space than free_chunk_size1 |
| 2948 | but we _could_ fit in it, shrink accordingly. |
| 2949 | */ |
| 2950 | if (size > free_chunk_size1) { |
| 2951 | |
| 2952 | if (free_chunk_size1 < |
| 2953 | (sizeof(struct jffs_raw_inode) + total_name_size + BLOCK_SIZE)){ |
| 2954 | /* The space left is too small to be of any |
| 2955 | use really. */ |
| 2956 | struct jffs_fm *dirty_fm |
| 2957 | = jffs_fmalloced(fmc, |
| 2958 | fmc->tail->offset + fmc->tail->size, |
| 2959 | free_chunk_size1, NULL); |
| 2960 | if (!dirty_fm) { |
| 2961 | printk(KERN_ERR "JFFS: " |
| 2962 | "jffs_garbage_collect_next: " |
| 2963 | "Failed to allocate `dirty' " |
| 2964 | "flash memory!\n"); |
| 2965 | err = -1; |
| 2966 | goto jffs_garbage_collect_next_end; |
| 2967 | } |
| 2968 | D1(printk("Dirtying end of flash - too small\n")); |
| 2969 | jffs_write_dummy_node(c, dirty_fm); |
| 2970 | err = 0; |
| 2971 | goto jffs_garbage_collect_next_end; |
| 2972 | } |
| 2973 | D1(printk("Reducing size of new node from %d to %d to avoid " |
| 2974 | " exceeding free_chunk_size1\n", |
| 2975 | size, free_chunk_size1)); |
| 2976 | |
| 2977 | size = free_chunk_size1; |
| 2978 | data_size = size - sizeof(struct jffs_raw_inode) |
| 2979 | - total_name_size; |
| 2980 | } |
| 2981 | |
| 2982 | |
| 2983 | /* Calculate the amount of space needed to hold the nodes |
| 2984 | which are remaining in the tail */ |
| 2985 | space_needed = fmc->min_free_size - (node->fm->offset % fmc->sector_size); |
| 2986 | |
| 2987 | /* From that, calculate how much 'extra' space we can use to |
| 2988 | increase the size of the node we're writing from the size |
| 2989 | of the node we're obsoleting |
| 2990 | */ |
| 2991 | if (space_needed > fmc->free_size) { |
| 2992 | /* If we've gone below min_free_size for some reason, |
| 2993 | don't fuck up. This is why we have |
| 2994 | min_free_size > sector_size. Whinge about it though, |
| 2995 | just so I can convince myself my maths is right. |
| 2996 | */ |
| 2997 | D1(printk(KERN_WARNING "jffs_garbage_collect_next(): " |
| 2998 | "space_needed %d exceeded free_size %d\n", |
| 2999 | space_needed, fmc->free_size)); |
| 3000 | extra_available = 0; |
| 3001 | } else { |
| 3002 | extra_available = fmc->free_size - space_needed; |
| 3003 | } |
| 3004 | |
| 3005 | /* Check that we don't use up any more 'extra' space than |
| 3006 | what's available */ |
| 3007 | if (size > JFFS_PAD(node->data_size) + total_name_size + |
| 3008 | sizeof(struct jffs_raw_inode) + extra_available) { |
| 3009 | D1(printk("Reducing size of new node from %d to %ld to avoid " |
| 3010 | "catching our tail\n", size, |
| 3011 | (long) (JFFS_PAD(node->data_size) + JFFS_PAD(node->name_size) + |
| 3012 | sizeof(struct jffs_raw_inode) + extra_available))); |
| 3013 | D1(printk("space_needed = %d, extra_available = %d\n", |
| 3014 | space_needed, extra_available)); |
| 3015 | |
| 3016 | size = JFFS_PAD(node->data_size) + total_name_size + |
| 3017 | sizeof(struct jffs_raw_inode) + extra_available; |
| 3018 | data_size = size - sizeof(struct jffs_raw_inode) |
| 3019 | - total_name_size; |
| 3020 | }; |
| 3021 | |
| 3022 | D2(printk(" total_name_size: %u\n", total_name_size)); |
| 3023 | D2(printk(" data_size: %u\n", data_size)); |
| 3024 | D2(printk(" size: %u\n", size)); |
| 3025 | D2(printk(" f->nsize: %u\n", f->nsize)); |
| 3026 | D2(printk(" f->size: %u\n", f->size)); |
| 3027 | D2(printk(" node->data_offset: %u\n", node->data_offset)); |
| 3028 | D2(printk(" free_chunk_size1: %u\n", free_chunk_size1)); |
| 3029 | D2(printk(" free_chunk_size2: %u\n", free_chunk_size2)); |
| 3030 | D2(printk(" node->fm->offset: 0x%08x\n", node->fm->offset)); |
| 3031 | |
| 3032 | if ((err = jffs_rewrite_data(f, node, data_size))) { |
| 3033 | printk(KERN_WARNING "jffs_rewrite_data() failed: %d\n", err); |
| 3034 | return err; |
| 3035 | } |
| 3036 | |
| 3037 | jffs_garbage_collect_next_end: |
| 3038 | D3(printk("jffs_garbage_collect_next: Leaving...\n")); |
| 3039 | return err; |
| 3040 | } /* jffs_garbage_collect_next */ |
| 3041 | |
| 3042 | |
| 3043 | /* If an obsolete node is partly going to be erased due to garbage |
| 3044 | collection, the part that isn't going to be erased must be filled |
| 3045 | with zeroes so that the scan of the flash will work smoothly next |
| 3046 | time. (The data in the file could for instance be a JFFS image |
| 3047 | which could cause enormous confusion during a scan of the flash |
| 3048 | device if we didn't do this.) |
| 3049 | There are two phases in this procedure: First, the clearing of |
| 3050 | the name and data parts of the node. Second, possibly also clearing |
| 3051 | a part of the raw inode as well. If the box is power cycled during |
| 3052 | the first phase, only the checksum of this node-to-be-cleared-at- |
| 3053 | the-end will be wrong. If the box is power cycled during, or after, |
| 3054 | the clearing of the raw inode, the information like the length of |
| 3055 | the name and data parts are zeroed. The next time the box is |
| 3056 | powered up, the scanning algorithm manages this faulty data too |
| 3057 | because: |
| 3058 | |
| 3059 | - The checksum is invalid and thus the raw inode must be discarded |
| 3060 | in any case. |
| 3061 | - If the lengths of the data part or the name part are zeroed, the |
| 3062 | scanning just continues after the raw inode. But after the inode |
| 3063 | the scanning procedure just finds zeroes which is the same as |
| 3064 | dirt. |
| 3065 | |
| 3066 | So, in the end, this could never fail. :-) Even if it does fail, |
| 3067 | the scanning algorithm should manage that too. */ |
| 3068 | |
| 3069 | static int |
| 3070 | jffs_clear_end_of_node(struct jffs_control *c, __u32 erase_size) |
| 3071 | { |
| 3072 | struct jffs_fm *fm; |
| 3073 | struct jffs_fmcontrol *fmc = c->fmc; |
| 3074 | __u32 zero_offset; |
| 3075 | __u32 zero_size; |
| 3076 | __u32 zero_offset_data; |
| 3077 | __u32 zero_size_data; |
| 3078 | __u32 cutting_raw_inode = 0; |
| 3079 | |
| 3080 | if (!(fm = jffs_cut_node(fmc, erase_size))) { |
| 3081 | D3(printk("jffs_clear_end_of_node(): fm == NULL\n")); |
| 3082 | return 0; |
| 3083 | } |
| 3084 | |
| 3085 | /* Where and how much shall we clear? */ |
| 3086 | zero_offset = fmc->head->offset + erase_size; |
| 3087 | zero_size = fm->offset + fm->size - zero_offset; |
| 3088 | |
| 3089 | /* Do we have to clear the raw_inode explicitly? */ |
| 3090 | if (fm->size - zero_size < sizeof(struct jffs_raw_inode)) { |
| 3091 | cutting_raw_inode = sizeof(struct jffs_raw_inode) |
| 3092 | - (fm->size - zero_size); |
| 3093 | } |
| 3094 | |
| 3095 | /* First, clear the name and data fields. */ |
| 3096 | zero_offset_data = zero_offset + cutting_raw_inode; |
| 3097 | zero_size_data = zero_size - cutting_raw_inode; |
| 3098 | flash_safe_acquire(fmc->mtd); |
| 3099 | flash_memset(fmc->mtd, zero_offset_data, 0, zero_size_data); |
| 3100 | flash_safe_release(fmc->mtd); |
| 3101 | |
| 3102 | /* Should we clear a part of the raw inode? */ |
| 3103 | if (cutting_raw_inode) { |
| 3104 | /* I guess it is ok to clear the raw inode in this order. */ |
| 3105 | flash_safe_acquire(fmc->mtd); |
| 3106 | flash_memset(fmc->mtd, zero_offset, 0, |
| 3107 | cutting_raw_inode); |
| 3108 | flash_safe_release(fmc->mtd); |
| 3109 | } |
| 3110 | |
| 3111 | return 0; |
| 3112 | } /* jffs_clear_end_of_node() */ |
| 3113 | |
| 3114 | /* Try to erase as much as possible of the dirt in the flash memory. */ |
| 3115 | static long |
| 3116 | jffs_try_to_erase(struct jffs_control *c) |
| 3117 | { |
| 3118 | struct jffs_fmcontrol *fmc = c->fmc; |
| 3119 | long erase_size; |
| 3120 | int err; |
| 3121 | __u32 offset; |
| 3122 | |
| 3123 | D3(printk("jffs_try_to_erase()\n")); |
| 3124 | |
| 3125 | erase_size = jffs_erasable_size(fmc); |
| 3126 | |
| 3127 | D2(printk("jffs_try_to_erase(): erase_size = %ld\n", erase_size)); |
| 3128 | |
| 3129 | if (erase_size == 0) { |
| 3130 | return 0; |
| 3131 | } |
| 3132 | else if (erase_size < 0) { |
| 3133 | printk(KERN_ERR "JFFS: jffs_try_to_erase: " |
| 3134 | "jffs_erasable_size returned %ld.\n", erase_size); |
| 3135 | return erase_size; |
| 3136 | } |
| 3137 | |
| 3138 | if ((err = jffs_clear_end_of_node(c, erase_size)) < 0) { |
| 3139 | printk(KERN_ERR "JFFS: jffs_try_to_erase: " |
| 3140 | "Clearing of node failed.\n"); |
| 3141 | return err; |
| 3142 | } |
| 3143 | |
| 3144 | offset = fmc->head->offset; |
| 3145 | |
| 3146 | /* Now, let's try to do the erase. */ |
| 3147 | if ((err = flash_erase_region(fmc->mtd, |
| 3148 | offset, erase_size)) < 0) { |
| 3149 | printk(KERN_ERR "JFFS: Erase of flash failed. " |
| 3150 | "offset = %u, erase_size = %ld\n", |
| 3151 | offset, erase_size); |
| 3152 | /* XXX: Here we should allocate this area as dirty |
| 3153 | with jffs_fmalloced or something similar. Now |
| 3154 | we just report the error. */ |
| 3155 | return err; |
| 3156 | } |
| 3157 | |
| 3158 | #if 0 |
| 3159 | /* Check if the erased sectors really got erased. */ |
| 3160 | { |
| 3161 | __u32 pos; |
| 3162 | __u32 end; |
| 3163 | |
| 3164 | pos = (__u32)flash_get_direct_pointer(to_kdev_t(c->sb->s_dev), offset); |
| 3165 | end = pos + erase_size; |
| 3166 | |
| 3167 | D2(printk("JFFS: Checking erased sector(s)...\n")); |
| 3168 | |
| 3169 | flash_safe_acquire(fmc->mtd); |
| 3170 | |
| 3171 | for (; pos < end; pos += 4) { |
| 3172 | if (*(__u32 *)pos != JFFS_EMPTY_BITMASK) { |
| 3173 | printk("JFFS: Erase failed! pos = 0x%lx\n", |
| 3174 | (long)pos); |
| 3175 | jffs_hexdump(fmc->mtd, pos, |
| 3176 | jffs_min(256, end - pos)); |
| 3177 | err = -1; |
| 3178 | break; |
| 3179 | } |
| 3180 | } |
| 3181 | |
| 3182 | flash_safe_release(fmc->mtd); |
| 3183 | |
| 3184 | if (!err) { |
| 3185 | D2(printk("JFFS: Erase succeeded.\n")); |
| 3186 | } |
| 3187 | else { |
| 3188 | /* XXX: Here we should allocate the memory |
| 3189 | with jffs_fmalloced() in order to prevent |
| 3190 | JFFS from using this area accidentally. */ |
| 3191 | return err; |
| 3192 | } |
| 3193 | } |
| 3194 | #endif |
| 3195 | |
| 3196 | /* Update the flash memory data structures. */ |
| 3197 | jffs_sync_erase(fmc, erase_size); |
| 3198 | |
| 3199 | return erase_size; |
| 3200 | } |
| 3201 | |
| 3202 | |
| 3203 | /* There are different criteria that should trigger a garbage collect: |
| 3204 | |
| 3205 | 1. There is too much dirt in the memory. |
| 3206 | 2. The free space is becoming small. |
| 3207 | 3. There are many versions of a node. |
| 3208 | |
| 3209 | The garbage collect should always be done in a manner that guarantees |
| 3210 | that future garbage collects cannot be locked. E.g. Rewritten chunks |
| 3211 | should not be too large (span more than one sector in the flash memory |
| 3212 | for exemple). Of course there is a limit on how intelligent this garbage |
| 3213 | collection can be. */ |
| 3214 | |
| 3215 | |
| 3216 | static int |
| 3217 | jffs_garbage_collect_now(struct jffs_control *c) |
| 3218 | { |
| 3219 | struct jffs_fmcontrol *fmc = c->fmc; |
| 3220 | long erased = 0; |
| 3221 | int result = 0; |
| 3222 | D1(int i = 1); |
| 3223 | D2(printk("***jffs_garbage_collect_now(): fmc->dirty_size = %u, fmc->free_size = 0x%x\n, fcs1=0x%x, fcs2=0x%x", |
| 3224 | fmc->dirty_size, fmc->free_size, jffs_free_size1(fmc), jffs_free_size2(fmc))); |
| 3225 | D2(jffs_print_fmcontrol(fmc)); |
| 3226 | |
| 3227 | // down(&fmc->gclock); |
| 3228 | |
| 3229 | /* If it is possible to garbage collect, do so. */ |
| 3230 | |
| 3231 | while (erased == 0) { |
| 3232 | D1(printk("***jffs_garbage_collect_now(): round #%u, " |
| 3233 | "fmc->dirty_size = %u\n", i++, fmc->dirty_size)); |
| 3234 | D2(jffs_print_fmcontrol(fmc)); |
| 3235 | |
| 3236 | if ((erased = jffs_try_to_erase(c)) < 0) { |
| 3237 | printk(KERN_WARNING "JFFS: Error in " |
| 3238 | "garbage collector.\n"); |
| 3239 | result = erased; |
| 3240 | goto gc_end; |
| 3241 | } |
| 3242 | if (erased) |
| 3243 | break; |
| 3244 | |
| 3245 | if (fmc->free_size == 0) { |
| 3246 | /* Argh */ |
| 3247 | printk(KERN_ERR "jffs_garbage_collect_now(): free_size == 0. This is BAD.\n"); |
| 3248 | result = -ENOSPC; |
| 3249 | break; |
| 3250 | } |
| 3251 | |
| 3252 | if (fmc->dirty_size < fmc->sector_size) { |
| 3253 | /* Actually, we _may_ have been able to free some, |
| 3254 | * if there are many overlapping nodes which aren't |
| 3255 | * actually marked dirty because they still have |
| 3256 | * some valid data in each. |
| 3257 | */ |
| 3258 | result = -ENOSPC; |
| 3259 | break; |
| 3260 | } |
| 3261 | |
| 3262 | /* Let's dare to make a garbage collect. */ |
| 3263 | if ((result = jffs_garbage_collect_next(c)) < 0) { |
| 3264 | printk(KERN_ERR "JFFS: Something " |
| 3265 | "has gone seriously wrong " |
| 3266 | "with a garbage collect.\n"); |
| 3267 | goto gc_end; |
| 3268 | } |
| 3269 | |
| 3270 | D1(printk(" jffs_garbage_collect_now(): erased: %ld\n", erased)); |
| 3271 | DJM(jffs_print_memory_allocation_statistics()); |
| 3272 | } |
| 3273 | |
| 3274 | gc_end: |
| 3275 | // up(&fmc->gclock); |
| 3276 | |
| 3277 | D3(printk(" jffs_garbage_collect_now(): Leaving...\n")); |
| 3278 | D1(if (erased) { |
| 3279 | printk("jffs_g_c_now(): erased = %ld\n", erased); |
| 3280 | jffs_print_fmcontrol(fmc); |
| 3281 | }); |
| 3282 | |
| 3283 | if (!erased && !result) |
| 3284 | return -ENOSPC; |
| 3285 | |
| 3286 | return result; |
| 3287 | } /* jffs_garbage_collect_now() */ |
| 3288 | |
| 3289 | |
| 3290 | /* Determine if it is reasonable to start garbage collection. |
| 3291 | We start a gc pass if either: |
| 3292 | - The number of free bytes < MIN_FREE_BYTES && at least one |
| 3293 | block is dirty, OR |
| 3294 | - The number of dirty bytes > MAX_DIRTY_BYTES |
| 3295 | */ |
| 3296 | static inline int thread_should_wake (struct jffs_control *c) |
| 3297 | { |
| 3298 | D1(printk (KERN_NOTICE "thread_should_wake(): free=%d, dirty=%d, blocksize=%d.\n", |
| 3299 | c->fmc->free_size, c->fmc->dirty_size, c->fmc->sector_size)); |
| 3300 | |
| 3301 | /* If there's not enough dirty space to free a block, there's no point. */ |
| 3302 | if (c->fmc->dirty_size < c->fmc->sector_size) { |
| 3303 | D2(printk(KERN_NOTICE "thread_should_wake(): Not waking. Insufficient dirty space\n")); |
| 3304 | return 0; |
| 3305 | } |
| 3306 | #if 1 |
| 3307 | /* If there is too much RAM used by the various structures, GC */ |
| 3308 | if (jffs_get_node_inuse() > (c->fmc->used_size/c->fmc->max_chunk_size * 5 + jffs_get_file_count() * 2 + 50)) { |
| 3309 | /* FIXME: Provide proof that this test can be satisfied. We |
| 3310 | don't want a filesystem doing endless GC just because this |
| 3311 | condition cannot ever be false. |
| 3312 | */ |
| 3313 | D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to number of nodes\n")); |
| 3314 | return 1; |
| 3315 | } |
| 3316 | #endif |
| 3317 | /* If there are fewer free bytes than the threshold, GC */ |
| 3318 | if (c->fmc->free_size < c->gc_minfree_threshold) { |
| 3319 | D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to insufficent free space\n")); |
| 3320 | return 1; |
| 3321 | } |
| 3322 | /* If there are more dirty bytes than the threshold, GC */ |
| 3323 | if (c->fmc->dirty_size > c->gc_maxdirty_threshold) { |
| 3324 | D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to excessive dirty space\n")); |
| 3325 | return 1; |
| 3326 | } |
| 3327 | /* FIXME: What about the "There are many versions of a node" condition? */ |
| 3328 | |
| 3329 | return 0; |
| 3330 | } |
| 3331 | |
| 3332 | |
| 3333 | void jffs_garbage_collect_trigger(struct jffs_control *c) |
| 3334 | { |
| 3335 | /* NOTE: We rely on the fact that we have the BKL here. |
| 3336 | * Otherwise, the gc_task could go away between the check |
| 3337 | * and the wake_up_process() |
| 3338 | */ |
| 3339 | if (c->gc_task && thread_should_wake(c)) |
| 3340 | send_sig(SIGHUP, c->gc_task, 1); |
| 3341 | } |
| 3342 | |
| 3343 | |
| 3344 | /* Kernel threads take (void *) as arguments. Thus we pass |
| 3345 | the jffs_control data as a (void *) and then cast it. */ |
| 3346 | int |
| 3347 | jffs_garbage_collect_thread(void *ptr) |
| 3348 | { |
| 3349 | struct jffs_control *c = (struct jffs_control *) ptr; |
| 3350 | struct jffs_fmcontrol *fmc = c->fmc; |
| 3351 | long erased; |
| 3352 | int result = 0; |
| 3353 | D1(int i = 1); |
| 3354 | |
| 3355 | daemonize("jffs_gcd"); |
| 3356 | |
| 3357 | c->gc_task = current; |
| 3358 | |
| 3359 | lock_kernel(); |
| 3360 | init_completion(&c->gc_thread_comp); /* barrier */ |
| 3361 | spin_lock_irq(¤t->sighand->siglock); |
| 3362 | siginitsetinv (¤t->blocked, sigmask(SIGHUP) | sigmask(SIGKILL) | sigmask(SIGSTOP) | sigmask(SIGCONT)); |
| 3363 | recalc_sigpending(); |
| 3364 | spin_unlock_irq(¤t->sighand->siglock); |
| 3365 | |
| 3366 | D1(printk (KERN_NOTICE "jffs_garbage_collect_thread(): Starting infinite loop.\n")); |
| 3367 | |
| 3368 | for (;;) { |
| 3369 | |
| 3370 | /* See if we need to start gc. If we don't, go to sleep. |
| 3371 | |
| 3372 | Current implementation is a BAD THING(tm). If we try |
| 3373 | to unmount the FS, the unmount operation will sleep waiting |
| 3374 | for this thread to exit. We need to arrange to send it a |
| 3375 | sig before the umount process sleeps. |
| 3376 | */ |
| 3377 | |
| 3378 | if (!thread_should_wake(c)) |
| 3379 | set_current_state (TASK_INTERRUPTIBLE); |
| 3380 | |
| 3381 | schedule(); /* Yes, we do this even if we want to go |
| 3382 | on immediately - we're a low priority |
| 3383 | background task. */ |
| 3384 | |
| 3385 | /* Put_super will send a SIGKILL and then wait on the sem. |
| 3386 | */ |
| 3387 | while (signal_pending(current)) { |
| 3388 | siginfo_t info; |
| 3389 | unsigned long signr = 0; |
| 3390 | |
Nigel Cunningham | ef2a701 | 2005-07-27 11:43:36 -0700 | [diff] [blame] | 3391 | if (try_to_freeze()) |
| 3392 | continue; |
| 3393 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3394 | spin_lock_irq(¤t->sighand->siglock); |
| 3395 | signr = dequeue_signal(current, ¤t->blocked, &info); |
| 3396 | spin_unlock_irq(¤t->sighand->siglock); |
| 3397 | |
| 3398 | switch(signr) { |
| 3399 | case SIGSTOP: |
| 3400 | D1(printk("jffs_garbage_collect_thread(): SIGSTOP received.\n")); |
| 3401 | set_current_state(TASK_STOPPED); |
| 3402 | schedule(); |
| 3403 | break; |
| 3404 | |
| 3405 | case SIGKILL: |
| 3406 | D1(printk("jffs_garbage_collect_thread(): SIGKILL received.\n")); |
| 3407 | c->gc_task = NULL; |
| 3408 | complete_and_exit(&c->gc_thread_comp, 0); |
| 3409 | } |
| 3410 | } |
| 3411 | |
| 3412 | |
| 3413 | D1(printk (KERN_NOTICE "jffs_garbage_collect_thread(): collecting.\n")); |
| 3414 | |
| 3415 | D3(printk (KERN_NOTICE "g_c_thread(): down biglock\n")); |
Ingo Molnar | 1eb0d67 | 2006-03-23 03:00:40 -0800 | [diff] [blame] | 3416 | mutex_lock(&fmc->biglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3417 | |
| 3418 | D1(printk("***jffs_garbage_collect_thread(): round #%u, " |
| 3419 | "fmc->dirty_size = %u\n", i++, fmc->dirty_size)); |
| 3420 | D2(jffs_print_fmcontrol(fmc)); |
| 3421 | |
| 3422 | if ((erased = jffs_try_to_erase(c)) < 0) { |
| 3423 | printk(KERN_WARNING "JFFS: Error in " |
| 3424 | "garbage collector: %ld.\n", erased); |
| 3425 | } |
| 3426 | |
| 3427 | if (erased) |
| 3428 | goto gc_end; |
| 3429 | |
| 3430 | if (fmc->free_size == 0) { |
| 3431 | /* Argh. Might as well commit suicide. */ |
| 3432 | printk(KERN_ERR "jffs_garbage_collect_thread(): free_size == 0. This is BAD.\n"); |
| 3433 | send_sig(SIGQUIT, c->gc_task, 1); |
| 3434 | // panic() |
| 3435 | goto gc_end; |
| 3436 | } |
| 3437 | |
| 3438 | /* Let's dare to make a garbage collect. */ |
| 3439 | if ((result = jffs_garbage_collect_next(c)) < 0) { |
| 3440 | printk(KERN_ERR "JFFS: Something " |
| 3441 | "has gone seriously wrong " |
| 3442 | "with a garbage collect: %d\n", result); |
| 3443 | } |
| 3444 | |
| 3445 | gc_end: |
| 3446 | D3(printk (KERN_NOTICE "g_c_thread(): up biglock\n")); |
Ingo Molnar | 1eb0d67 | 2006-03-23 03:00:40 -0800 | [diff] [blame] | 3447 | mutex_unlock(&fmc->biglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3448 | } /* for (;;) */ |
| 3449 | } /* jffs_garbage_collect_thread() */ |