Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/recovery.c |
| 3 | * |
| 4 | * Written by Stephen C. Tweedie <sct@redhat.com>, 1999 |
| 5 | * |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 6 | * Copyright 1999-2000 Red Hat Software --- All Rights Reserved |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 7 | * |
| 8 | * This file is part of the Linux kernel and is made available under |
| 9 | * the terms of the GNU General Public License, version 2, or at your |
| 10 | * option, any later version, incorporated herein by reference. |
| 11 | * |
| 12 | * Journal recovery routines for the generic filesystem journaling code; |
| 13 | * part of the ext2fs journaling system. |
| 14 | */ |
| 15 | |
| 16 | #ifndef __KERNEL__ |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 17 | #include "jfs_user.h" |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 18 | #else |
| 19 | #include <linux/sched.h> |
| 20 | #include <linux/fs.h> |
| 21 | #include <linux/jfs.h> |
| 22 | #include <linux/errno.h> |
| 23 | #include <linux/malloc.h> |
| 24 | #include <linux/locks.h> |
| 25 | #include <linux/buffer.h> |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 26 | #endif |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 27 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 28 | /* |
| 29 | * Maintain information about the progress of the recovery job, so that |
| 30 | * the different passes can carry information between them. |
| 31 | */ |
| 32 | struct recovery_info |
| 33 | { |
| 34 | tid_t start_transaction; |
| 35 | tid_t end_transaction; |
| 36 | |
| 37 | int nr_replays; |
| 38 | int nr_revokes; |
| 39 | int nr_revoke_hits; |
| 40 | }; |
| 41 | |
| 42 | enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY}; |
| 43 | static int do_one_pass(journal_t *, struct recovery_info *, enum passtype); |
| 44 | static int scan_revoke_records(journal_t *, struct buffer_head *, tid_t, struct recovery_info *); |
| 45 | |
| 46 | #ifdef __KERNEL__ |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 47 | |
| 48 | /* Release readahead buffers after use */ |
| 49 | static void brelse_array(struct buffer_head *b[], int n) |
| 50 | { |
| 51 | while (--n >= 0) |
| 52 | brelse (b[n]); |
| 53 | } |
| 54 | |
| 55 | |
| 56 | /* |
| 57 | * When reading from the journal, we are going through the block device |
| 58 | * layer directly and so there is no readahead being done for us. We |
| 59 | * need to implement any readahead ourselves if we want it to happen at |
| 60 | * all. Recovery is basically one long sequential read, so make sure we |
| 61 | * do the IO in reasonably large chunks. |
| 62 | * |
| 63 | * This is not so critical that we need to be enormously clever about |
| 64 | * the readahead size, though. 128K is a purely arbitrary, good-enough |
| 65 | * fixed value. |
| 66 | */ |
| 67 | |
| 68 | static int do_readahead(journal_t *journal, unsigned int start) |
| 69 | { |
| 70 | int err; |
| 71 | unsigned int max, nbufs, next, blocknr; |
| 72 | struct buffer_head *bh; |
| 73 | |
| 74 | #define MAXBUF 8 |
| 75 | struct buffer_head * bufs[MAXBUF]; |
| 76 | |
| 77 | /* Do up to 128K of readahead */ |
| 78 | max = start + (128 * 1024 / journal->j_blocksize); |
| 79 | if (max > journal->j_maxlen) |
| 80 | max = journal->j_maxlen; |
| 81 | |
| 82 | /* Do the readahead itself. We'll submit MAXBUF buffer_heads at |
| 83 | * a time to the block device IO layer. */ |
| 84 | |
| 85 | nbufs = 0; |
| 86 | |
| 87 | for (next = start; next < max; next++) { |
| 88 | blocknr = next; |
| 89 | if (journal->j_inode) |
| 90 | blocknr = bmap(journal->j_inode, next); |
| 91 | if (!blocknr) { |
| 92 | printk (KERN_ERR "JFS: bad block at offset %u\n", |
| 93 | next); |
| 94 | err = -EIO; |
| 95 | goto failed; |
| 96 | } |
| 97 | |
| 98 | bh = getblk(journal->j_dev, blocknr, journal->j_blocksize); |
| 99 | if (!bh) { |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 100 | err = -ENOMEM; |
| 101 | goto failed; |
| 102 | } |
| 103 | |
| 104 | if (!buffer_uptodate(bh) && !buffer_locked(bh)) { |
| 105 | bufs[nbufs++] = bh; |
| 106 | if (nbufs == MAXBUF) { |
| 107 | ll_rw_block(READ, nbufs, bufs); |
| 108 | brelse_array(bufs, nbufs); |
| 109 | nbufs = 0; |
| 110 | } |
| 111 | } else |
| 112 | brelse(bh); |
| 113 | } |
| 114 | |
| 115 | if (nbufs) |
| 116 | ll_rw_block(READ, nbufs, bufs); |
| 117 | err = 0; |
| 118 | |
| 119 | failed: |
| 120 | if (nbufs) |
| 121 | brelse_array(bufs, nbufs); |
| 122 | return err; |
| 123 | } |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 124 | |
| 125 | #endif /* __KERNEL__ */ |
| 126 | |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 127 | |
| 128 | /* |
| 129 | * Read a block from the journal |
| 130 | */ |
| 131 | |
| 132 | static int jread(struct buffer_head **bhp, journal_t *journal, |
| 133 | unsigned int offset) |
| 134 | { |
| 135 | unsigned int blocknr; |
| 136 | struct buffer_head *bh; |
| 137 | |
| 138 | *bhp = NULL; |
| 139 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 140 | J_ASSERT (offset < journal->j_maxlen); |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 141 | |
| 142 | blocknr = offset; |
| 143 | if (journal->j_inode) |
| 144 | blocknr = bmap(journal->j_inode, offset); |
| 145 | |
| 146 | if (!blocknr) { |
| 147 | printk (KERN_ERR "JFS: bad block at offset %u\n", |
| 148 | offset); |
| 149 | return -EIO; |
| 150 | } |
| 151 | |
| 152 | bh = getblk(journal->j_dev, blocknr, journal->j_blocksize); |
| 153 | if (!bh) |
| 154 | return -ENOMEM; |
| 155 | |
| 156 | if (!buffer_uptodate(bh)) { |
| 157 | /* If this is a brand new buffer, start readahead. |
| 158 | Otherwise, we assume we are already reading it. */ |
| 159 | if (!buffer_req(bh)) |
| 160 | do_readahead(journal, offset); |
| 161 | wait_on_buffer(bh); |
| 162 | } |
| 163 | |
| 164 | if (!buffer_uptodate(bh)) { |
| 165 | printk (KERN_ERR "JFS: Failed to read block at offset %u\n", |
| 166 | offset); |
| 167 | brelse(bh); |
| 168 | return -EIO; |
| 169 | } |
| 170 | |
| 171 | *bhp = bh; |
| 172 | return 0; |
| 173 | } |
| 174 | |
| 175 | |
| 176 | /* |
| 177 | * Count the number of in-use tags in a journal descriptor block. |
| 178 | */ |
| 179 | |
| 180 | int count_tags(struct buffer_head *bh, int size) |
| 181 | { |
| 182 | char * tagp; |
| 183 | journal_block_tag_t * tag; |
| 184 | int nr = 0; |
| 185 | |
| 186 | tagp = &bh->b_data[sizeof(journal_header_t)]; |
| 187 | |
| 188 | while ((tagp - bh->b_data + sizeof(journal_block_tag_t)) <= size) { |
| 189 | tag = (journal_block_tag_t *) tagp; |
| 190 | |
| 191 | nr++; |
| 192 | tagp += sizeof(journal_block_tag_t); |
| 193 | if (!(tag->t_flags & htonl(JFS_FLAG_SAME_UUID))) |
| 194 | tagp += 16; |
| 195 | |
| 196 | if (tag->t_flags & htonl(JFS_FLAG_LAST_TAG)) |
| 197 | break; |
| 198 | } |
| 199 | |
| 200 | return nr; |
| 201 | } |
| 202 | |
| 203 | |
| 204 | /* Make sure we wrap around the log correctly! */ |
| 205 | #define wrap(journal, var) \ |
| 206 | do { \ |
| 207 | if (var >= (journal)->j_last) \ |
| 208 | var -= ((journal)->j_last - (journal)->j_first); \ |
| 209 | } while (0) |
| 210 | |
| 211 | /* |
| 212 | * journal_recover |
| 213 | * |
| 214 | * The primary function for recovering the log contents when mounting a |
| 215 | * journaled device. |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 216 | * |
| 217 | * Recovery is done in three passes. In the first pass, we look for the |
| 218 | * end of the log. In the second, we assemble the list of revoke |
| 219 | * blocks. In the third and final pass, we replay any un-revoked blocks |
| 220 | * in the log. |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 221 | */ |
| 222 | |
| 223 | int journal_recover(journal_t *journal) |
| 224 | { |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 225 | int err; |
| 226 | journal_superblock_t * sb; |
| 227 | |
| 228 | struct recovery_info info = {}; |
| 229 | |
| 230 | sb = journal->j_superblock; |
| 231 | |
| 232 | /* |
| 233 | * The journal superblock's s_start field (the current log head) |
| 234 | * is always zero if, and only if, the journal was cleanly |
| 235 | * unmounted. |
| 236 | */ |
| 237 | |
| 238 | if (!sb->s_start) { |
| 239 | jfs_debug(1, "No recovery required, last transaction %d\n", |
| 240 | ntohl(sb->s_sequence)); |
| 241 | journal->j_transaction_sequence = ntohl(sb->s_sequence) + 1; |
| 242 | return 0; |
| 243 | } |
| 244 | |
| 245 | |
| 246 | err = do_one_pass(journal, &info, PASS_SCAN); |
| 247 | if (!err) |
| 248 | err = do_one_pass(journal, &info, PASS_REVOKE); |
| 249 | if (!err) |
| 250 | err = do_one_pass(journal, &info, PASS_REPLAY); |
| 251 | |
| 252 | jfs_debug(0, "JFS: recovery, exit status %d, " |
| 253 | "recovered transactions %u to %u\n", |
| 254 | err, info.start_transaction, info.end_transaction); |
| 255 | jfs_debug(0, "JFS: Replayed %d and revoked %d/%d blocks\n", |
| 256 | info.nr_replays, info.nr_revoke_hits, info.nr_revokes); |
| 257 | |
| 258 | /* Restart the log at the next transaction ID, thus invalidating |
| 259 | * any existing commit records in the log. */ |
| 260 | journal->j_transaction_sequence = ++info.end_transaction; |
| 261 | |
| 262 | journal_clear_revoke(journal); |
| 263 | fsync_dev(journal->j_dev); |
| 264 | return err; |
| 265 | } |
| 266 | |
| 267 | static int do_one_pass(journal_t *journal, struct recovery_info *info, |
| 268 | enum passtype pass) |
| 269 | { |
| 270 | |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 271 | unsigned int first_commit_ID, next_commit_ID; |
| 272 | unsigned long next_log_block; |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 273 | int err, success = 0; |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 274 | journal_superblock_t * sb; |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 275 | journal_header_t * tmp; |
| 276 | struct buffer_head * bh; |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 277 | unsigned int sequence; |
| 278 | int blocktype; |
| 279 | |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 280 | /* Precompute the maximum metadata descriptors in a descriptor block */ |
| 281 | int MAX_BLOCKS_PER_DESC; |
| 282 | MAX_BLOCKS_PER_DESC = ((journal->j_blocksize-sizeof(journal_header_t)) |
| 283 | / sizeof(journal_block_tag_t)); |
| 284 | |
| 285 | /* |
| 286 | * First thing is to establish what we expect to find in the log |
| 287 | * (in terms of transaction IDs), and where (in terms of log |
| 288 | * block offsets): query the superblock. |
| 289 | */ |
| 290 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 291 | sb = journal->j_superblock; |
| 292 | next_commit_ID = ntohl(sb->s_sequence); |
| 293 | next_log_block = ntohl(sb->s_start); |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 294 | |
| 295 | first_commit_ID = next_commit_ID; |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 296 | if (pass == PASS_SCAN) |
| 297 | info->start_transaction = first_commit_ID; |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 298 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 299 | jfs_debug(1, "Starting recovery pass %d\n", pass); |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 300 | |
| 301 | /* |
| 302 | * Now we walk through the log, transaction by transaction, |
| 303 | * making sure that each transaction has a commit block in the |
| 304 | * expected place. Each complete transaction gets replayed back |
| 305 | * into the main filesystem. |
| 306 | */ |
| 307 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 308 | while (1) { |
| 309 | int flags; |
| 310 | char * tagp; |
| 311 | journal_block_tag_t * tag; |
| 312 | struct buffer_head * obh; |
| 313 | struct buffer_head * nbh; |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 314 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 315 | /* If we already know where to stop the log traversal, |
| 316 | * check right now that we haven't gone past the end of |
| 317 | * the log. */ |
| 318 | |
| 319 | if (pass != PASS_SCAN) |
| 320 | if (tid_geq(next_commit_ID, info->end_transaction)) |
| 321 | break; |
| 322 | |
| 323 | jfs_debug(2, "Scanning for sequence ID %u at %lu/%lu\n", |
| 324 | next_commit_ID, next_log_block, journal->j_last); |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 325 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 326 | /* Skip over each chunk of the transaction looking |
| 327 | * either the next descriptor block or the final commit |
| 328 | * record. */ |
| 329 | |
| 330 | jfs_debug(3, "JFS: checking block %ld\n", next_log_block); |
| 331 | err = jread(&bh, journal, next_log_block); |
| 332 | if (err) |
| 333 | goto failed; |
| 334 | |
| 335 | next_log_block++; |
| 336 | wrap(journal, next_log_block); |
| 337 | |
| 338 | /* What kind of buffer is it? |
| 339 | * |
| 340 | * If it is a descriptor block, check that it has the |
| 341 | * expected sequence number. Otherwise, we're all done |
| 342 | * here. */ |
| 343 | |
| 344 | tmp = (journal_header_t *) bh->b_data; |
| 345 | |
| 346 | if (tmp->h_magic != htonl(JFS_MAGIC_NUMBER)) { |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 347 | brelse(bh); |
| 348 | break; |
| 349 | } |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 350 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 351 | blocktype = ntohl(tmp->h_blocktype); |
| 352 | sequence = ntohl(tmp->h_sequence); |
| 353 | jfs_debug(3, "Found magic %d, sequence %d\n", |
| 354 | blocktype, sequence); |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 355 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 356 | if (sequence != next_commit_ID) { |
| 357 | brelse(bh); |
| 358 | break; |
| 359 | } |
| 360 | |
| 361 | /* OK, we have a valid descriptor block which matches |
| 362 | * all of the sequence number checks. What are we going |
| 363 | * to do with it? That depends on the pass... */ |
| 364 | |
| 365 | switch(blocktype) { |
| 366 | case JFS_DESCRIPTOR_BLOCK: |
| 367 | /* If it is a valid descriptor block, replay it |
| 368 | * in pass REPLAY; otherwise, just skip over the |
| 369 | * blocks it describes. */ |
| 370 | if (pass != PASS_REPLAY) { |
| 371 | next_log_block += count_tags(bh, journal->j_blocksize); |
| 372 | wrap(journal, next_log_block); |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 373 | brelse(bh); |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 374 | continue; |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 375 | } |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 376 | |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 377 | /* A descriptor block: we can now write all of |
| 378 | * the data blocks. Yay, useful work is finally |
| 379 | * getting done here! */ |
| 380 | |
| 381 | tagp = &bh->b_data[sizeof(journal_header_t)]; |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 382 | while ((tagp - bh->b_data +sizeof(journal_block_tag_t)) |
| 383 | <= journal->j_blocksize) { |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 384 | unsigned long io_block; |
| 385 | |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 386 | tag = (journal_block_tag_t *) tagp; |
| 387 | flags = ntohl(tag->t_flags); |
| 388 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 389 | io_block = next_log_block++; |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 390 | wrap(journal, next_log_block); |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 391 | err = jread(&obh, journal, io_block); |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 392 | if (err) { |
| 393 | /* Recover what we can, but |
| 394 | * report failure at the end. */ |
| 395 | success = err; |
| 396 | printk (KERN_ERR |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 397 | "JFS: IO error %d recovering " |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 398 | "block %ld in log\n", |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 399 | err, io_block); |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 400 | } else { |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 401 | unsigned long blocknr; |
| 402 | |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 403 | J_ASSERT(obh != NULL); |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 404 | blocknr = ntohl(tag->t_blocknr); |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 405 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 406 | /* If the block has been |
| 407 | * revoked, then we're all done |
| 408 | * here. */ |
| 409 | if (journal_test_revoke |
| 410 | (journal, blocknr, |
| 411 | next_commit_ID)) { |
| 412 | brelse(obh); |
| 413 | ++info->nr_revoke_hits; |
| 414 | goto skip_write; |
| 415 | } |
| 416 | |
| 417 | /* Find a buffer for the new |
| 418 | * data being restored */ |
| 419 | nbh = getblk(journal->j_dev, blocknr, |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 420 | journal->j_blocksize); |
| 421 | if (nbh == NULL) { |
| 422 | printk(KERN_ERR |
| 423 | "JFS: Out of memory " |
| 424 | "during recovery.\n"); |
| 425 | err = -ENOMEM; |
| 426 | brelse(bh); |
| 427 | brelse(obh); |
| 428 | goto failed; |
| 429 | } |
| 430 | |
| 431 | memcpy(nbh->b_data, obh->b_data, |
| 432 | journal->j_blocksize); |
| 433 | if (flags & JFS_FLAG_ESCAPE) { |
| 434 | * ((unsigned int *) bh->b_data) = htonl(JFS_MAGIC_NUMBER); |
| 435 | } |
| 436 | |
| 437 | mark_buffer_dirty(nbh, 1); |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 438 | ++info->nr_replays; |
| 439 | // ll_rw_block(WRITE, 1, &nbh); |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 440 | brelse(obh); |
| 441 | brelse(nbh); |
| 442 | } |
| 443 | |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 444 | skip_write: |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 445 | tagp += sizeof(journal_block_tag_t); |
| 446 | if (!(flags & JFS_FLAG_SAME_UUID)) |
| 447 | tagp += 16; |
| 448 | |
| 449 | if (flags & JFS_FLAG_LAST_TAG) |
| 450 | break; |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 451 | } |
| 452 | |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 453 | brelse(bh); |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 454 | continue; |
| 455 | |
| 456 | case JFS_COMMIT_BLOCK: |
| 457 | /* Found an expected commit block: not much to |
| 458 | * do other than move on to the next sequence |
| 459 | * number. */ |
| 460 | brelse(bh); |
| 461 | next_commit_ID++; |
| 462 | continue; |
| 463 | |
| 464 | case JFS_REVOKE_BLOCK: |
| 465 | /* If we aren't in the REVOKE pass, then we can |
| 466 | * just skip over this block. */ |
| 467 | if (pass != PASS_REVOKE) { |
| 468 | brelse(bh); |
| 469 | continue; |
| 470 | } |
| 471 | |
| 472 | err = scan_revoke_records(journal, bh, |
| 473 | next_commit_ID, info); |
| 474 | brelse(bh); |
| 475 | if (err) |
| 476 | goto failed; |
| 477 | continue; |
| 478 | |
| 479 | default: |
| 480 | jfs_debug(3, "Unrecognised magic %d, end of scan.\n", |
| 481 | blocktype); |
| 482 | goto done; |
| 483 | } |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 484 | } |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 485 | |
| 486 | done: |
| 487 | /* |
| 488 | * We broke out of the log scan loop: either we came to the |
| 489 | * known end of the log or we found an unexpected block in the |
| 490 | * log. If the latter happened, then we know that the "current" |
| 491 | * transaction marks the end of the valid log. |
| 492 | */ |
| 493 | |
| 494 | if (pass == PASS_SCAN) |
| 495 | info->end_transaction = next_commit_ID; |
| 496 | else { |
| 497 | /* It's really bad news if different passes end up at |
| 498 | * different places (but possible due to IO errors). */ |
| 499 | if (info->end_transaction != next_commit_ID) { |
| 500 | printk (KERN_ERR "JFS: recovery pass %d ended at " |
| 501 | "transaction %u, expected %u\n", |
| 502 | pass, next_commit_ID, info->end_transaction); |
| 503 | if (!success) |
| 504 | success = -EIO; |
| 505 | } |
| 506 | } |
| 507 | |
| 508 | return success; |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 509 | |
| 510 | failed: |
Theodore Ts'o | 3b5386d | 2000-08-14 14:25:19 +0000 | [diff] [blame] | 511 | return err; |
| 512 | } |
Theodore Ts'o | 0e8a956 | 2000-12-09 06:41:25 +0000 | [diff] [blame^] | 513 | |
| 514 | |
| 515 | /* Scan a revoke record, marking all blocks mentioned as revoked. */ |
| 516 | |
| 517 | static int scan_revoke_records(journal_t *journal, struct buffer_head *bh, |
| 518 | tid_t sequence, struct recovery_info *info) |
| 519 | { |
| 520 | journal_revoke_header_t *header; |
| 521 | int offset, max; |
| 522 | |
| 523 | header = (journal_revoke_header_t *) bh->b_data; |
| 524 | offset = sizeof(journal_revoke_header_t); |
| 525 | max = ntohl(header->r_count); |
| 526 | |
| 527 | while (offset < max) { |
| 528 | unsigned long blocknr; |
| 529 | int err; |
| 530 | |
| 531 | blocknr = * ((unsigned int *) bh->b_data+offset); |
| 532 | offset += 4; |
| 533 | err = journal_set_revoke(journal, blocknr, sequence); |
| 534 | if (err) |
| 535 | return err; |
| 536 | ++info->nr_revokes; |
| 537 | } |
| 538 | return 0; |
| 539 | } |