Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Uwe Kleine-König | 5886269 | 2007-05-09 07:51:49 +0200 | [diff] [blame] | 2 | * linux/fs/jbd/checkpoint.c |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 3 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * Written by Stephen C. Tweedie <sct@redhat.com>, 1999 |
| 5 | * |
| 6 | * Copyright 1999 Red Hat Software --- All Rights Reserved |
| 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 | * |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 12 | * Checkpoint routines for the generic filesystem journaling code. |
| 13 | * Part of the ext2fs journaling system. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | * |
| 15 | * Checkpointing is the process of ensuring that a section of the log is |
| 16 | * committed fully to disk, so that that portion of the log can be |
| 17 | * reused. |
| 18 | */ |
| 19 | |
| 20 | #include <linux/time.h> |
| 21 | #include <linux/fs.h> |
| 22 | #include <linux/jbd.h> |
| 23 | #include <linux/errno.h> |
| 24 | #include <linux/slab.h> |
Lukas Czerner | 99cb1a3 | 2011-05-23 18:33:02 +0200 | [diff] [blame] | 25 | #include <trace/events/jbd.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | |
| 27 | /* |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 28 | * Unlink a buffer from a transaction checkpoint list. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | * |
| 30 | * Called with j_list_lock held. |
| 31 | */ |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 32 | static inline void __buffer_unlink_first(struct journal_head *jh) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | { |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 34 | transaction_t *transaction = jh->b_cp_transaction; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | |
Mark Fasheh | 7c8903f | 2006-02-14 13:53:03 -0800 | [diff] [blame] | 36 | jh->b_cpnext->b_cpprev = jh->b_cpprev; |
| 37 | jh->b_cpprev->b_cpnext = jh->b_cpnext; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 38 | if (transaction->t_checkpoint_list == jh) { |
Mark Fasheh | 7c8903f | 2006-02-14 13:53:03 -0800 | [diff] [blame] | 39 | transaction->t_checkpoint_list = jh->b_cpnext; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 40 | if (transaction->t_checkpoint_list == jh) |
| 41 | transaction->t_checkpoint_list = NULL; |
| 42 | } |
| 43 | } |
| 44 | |
| 45 | /* |
| 46 | * Unlink a buffer from a transaction checkpoint(io) list. |
| 47 | * |
| 48 | * Called with j_list_lock held. |
| 49 | */ |
| 50 | static inline void __buffer_unlink(struct journal_head *jh) |
| 51 | { |
| 52 | transaction_t *transaction = jh->b_cp_transaction; |
| 53 | |
| 54 | __buffer_unlink_first(jh); |
| 55 | if (transaction->t_checkpoint_io_list == jh) { |
| 56 | transaction->t_checkpoint_io_list = jh->b_cpnext; |
| 57 | if (transaction->t_checkpoint_io_list == jh) |
| 58 | transaction->t_checkpoint_io_list = NULL; |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | /* |
| 63 | * Move a buffer from the checkpoint list to the checkpoint io list |
| 64 | * |
| 65 | * Called with j_list_lock held |
| 66 | */ |
| 67 | static inline void __buffer_relink_io(struct journal_head *jh) |
| 68 | { |
| 69 | transaction_t *transaction = jh->b_cp_transaction; |
| 70 | |
| 71 | __buffer_unlink_first(jh); |
| 72 | |
| 73 | if (!transaction->t_checkpoint_io_list) { |
| 74 | jh->b_cpnext = jh->b_cpprev = jh; |
| 75 | } else { |
| 76 | jh->b_cpnext = transaction->t_checkpoint_io_list; |
| 77 | jh->b_cpprev = transaction->t_checkpoint_io_list->b_cpprev; |
| 78 | jh->b_cpprev->b_cpnext = jh; |
| 79 | jh->b_cpnext->b_cpprev = jh; |
| 80 | } |
| 81 | transaction->t_checkpoint_io_list = jh; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | } |
| 83 | |
| 84 | /* |
| 85 | * Try to release a checkpointed buffer from its transaction. |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 86 | * Returns 1 if we released it and 2 if we also released the |
| 87 | * whole transaction. |
| 88 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | * Requires j_list_lock |
| 90 | * Called under jbd_lock_bh_state(jh2bh(jh)), and drops it |
| 91 | */ |
| 92 | static int __try_to_free_cp_buf(struct journal_head *jh) |
| 93 | { |
| 94 | int ret = 0; |
| 95 | struct buffer_head *bh = jh2bh(jh); |
| 96 | |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 97 | if (jh->b_jlist == BJ_None && !buffer_locked(bh) && |
Hidehiro Kawai | 9f818b4 | 2008-10-22 14:15:02 -0700 | [diff] [blame] | 98 | !buffer_dirty(bh) && !buffer_write_io_error(bh)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | JBUFFER_TRACE(jh, "remove from checkpoint list"); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 100 | ret = __journal_remove_checkpoint(jh) + 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | jbd_unlock_bh_state(bh); |
| 102 | journal_remove_journal_head(bh); |
| 103 | BUFFER_TRACE(bh, "release"); |
| 104 | __brelse(bh); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | } else { |
| 106 | jbd_unlock_bh_state(bh); |
| 107 | } |
| 108 | return ret; |
| 109 | } |
| 110 | |
| 111 | /* |
| 112 | * __log_wait_for_space: wait until there is space in the journal. |
| 113 | * |
| 114 | * Called under j-state_lock *only*. It will be unlocked if we have to wait |
| 115 | * for a checkpoint to free up some space in the log. |
| 116 | */ |
| 117 | void __log_wait_for_space(journal_t *journal) |
| 118 | { |
Theodore Ts'o | e219cca | 2008-11-06 22:37:59 -0500 | [diff] [blame] | 119 | int nblocks, space_left; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | assert_spin_locked(&journal->j_state_lock); |
| 121 | |
| 122 | nblocks = jbd_space_needed(journal); |
| 123 | while (__log_space_left(journal) < nblocks) { |
| 124 | if (journal->j_flags & JFS_ABORT) |
| 125 | return; |
| 126 | spin_unlock(&journal->j_state_lock); |
Arjan van de Ven | 2c68ee7 | 2006-03-23 03:00:35 -0800 | [diff] [blame] | 127 | mutex_lock(&journal->j_checkpoint_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | |
| 129 | /* |
| 130 | * Test again, another process may have checkpointed while we |
Duane Griffin | be07c4e | 2008-10-22 14:15:03 -0700 | [diff] [blame] | 131 | * were waiting for the checkpoint lock. If there are no |
Theodore Ts'o | e219cca | 2008-11-06 22:37:59 -0500 | [diff] [blame] | 132 | * transactions ready to be checkpointed, try to recover |
| 133 | * journal space by calling cleanup_journal_tail(), and if |
| 134 | * that doesn't work, by waiting for the currently committing |
| 135 | * transaction to complete. If there is absolutely no way |
| 136 | * to make progress, this is either a BUG or corrupted |
| 137 | * filesystem, so abort the journal and leave a stack |
| 138 | * trace for forensic evidence. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | */ |
| 140 | spin_lock(&journal->j_state_lock); |
Duane Griffin | be07c4e | 2008-10-22 14:15:03 -0700 | [diff] [blame] | 141 | spin_lock(&journal->j_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | nblocks = jbd_space_needed(journal); |
Theodore Ts'o | e219cca | 2008-11-06 22:37:59 -0500 | [diff] [blame] | 143 | space_left = __log_space_left(journal); |
| 144 | if (space_left < nblocks) { |
Duane Griffin | be07c4e | 2008-10-22 14:15:03 -0700 | [diff] [blame] | 145 | int chkpt = journal->j_checkpoint_transactions != NULL; |
Theodore Ts'o | e219cca | 2008-11-06 22:37:59 -0500 | [diff] [blame] | 146 | tid_t tid = 0; |
Duane Griffin | be07c4e | 2008-10-22 14:15:03 -0700 | [diff] [blame] | 147 | |
Theodore Ts'o | e219cca | 2008-11-06 22:37:59 -0500 | [diff] [blame] | 148 | if (journal->j_committing_transaction) |
| 149 | tid = journal->j_committing_transaction->t_tid; |
Duane Griffin | be07c4e | 2008-10-22 14:15:03 -0700 | [diff] [blame] | 150 | spin_unlock(&journal->j_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | spin_unlock(&journal->j_state_lock); |
Duane Griffin | be07c4e | 2008-10-22 14:15:03 -0700 | [diff] [blame] | 152 | if (chkpt) { |
| 153 | log_do_checkpoint(journal); |
Theodore Ts'o | e219cca | 2008-11-06 22:37:59 -0500 | [diff] [blame] | 154 | } else if (cleanup_journal_tail(journal) == 0) { |
| 155 | /* We were able to recover space; yay! */ |
| 156 | ; |
| 157 | } else if (tid) { |
| 158 | log_wait_commit(journal, tid); |
Duane Griffin | be07c4e | 2008-10-22 14:15:03 -0700 | [diff] [blame] | 159 | } else { |
Theodore Ts'o | e219cca | 2008-11-06 22:37:59 -0500 | [diff] [blame] | 160 | printk(KERN_ERR "%s: needed %d blocks and " |
| 161 | "only had %d space available\n", |
| 162 | __func__, nblocks, space_left); |
| 163 | printk(KERN_ERR "%s: no way to get more " |
| 164 | "journal space\n", __func__); |
| 165 | WARN_ON(1); |
Duane Griffin | be07c4e | 2008-10-22 14:15:03 -0700 | [diff] [blame] | 166 | journal_abort(journal, 0); |
| 167 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | spin_lock(&journal->j_state_lock); |
Duane Griffin | be07c4e | 2008-10-22 14:15:03 -0700 | [diff] [blame] | 169 | } else { |
| 170 | spin_unlock(&journal->j_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | } |
Arjan van de Ven | 2c68ee7 | 2006-03-23 03:00:35 -0800 | [diff] [blame] | 172 | mutex_unlock(&journal->j_checkpoint_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | } |
| 174 | } |
| 175 | |
| 176 | /* |
| 177 | * We were unable to perform jbd_trylock_bh_state() inside j_list_lock. |
| 178 | * The caller must restart a list walk. Wait for someone else to run |
| 179 | * jbd_unlock_bh_state(). |
| 180 | */ |
| 181 | static void jbd_sync_bh(journal_t *journal, struct buffer_head *bh) |
Josh Triplett | e7ab8d6 | 2006-09-27 01:49:26 -0700 | [diff] [blame] | 182 | __releases(journal->j_list_lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | { |
| 184 | get_bh(bh); |
| 185 | spin_unlock(&journal->j_list_lock); |
| 186 | jbd_lock_bh_state(bh); |
| 187 | jbd_unlock_bh_state(bh); |
| 188 | put_bh(bh); |
| 189 | } |
| 190 | |
| 191 | /* |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 192 | * Clean up transaction's list of buffers submitted for io. |
| 193 | * We wait for any pending IO to complete and remove any clean |
| 194 | * buffers. Note that we take the buffers in the opposite ordering |
| 195 | * from the one in which they were submitted for IO. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | * |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 197 | * Return 0 on success, and return <0 if some buffers have failed |
| 198 | * to be written out. |
| 199 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | * Called with j_list_lock held. |
| 201 | */ |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 202 | static int __wait_cp_io(journal_t *journal, transaction_t *transaction) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | { |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 204 | struct journal_head *jh; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | struct buffer_head *bh; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 206 | tid_t this_tid; |
| 207 | int released = 0; |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 208 | int ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 210 | this_tid = transaction->t_tid; |
| 211 | restart: |
| 212 | /* Did somebody clean up the transaction in the meanwhile? */ |
| 213 | if (journal->j_checkpoint_transactions != transaction || |
| 214 | transaction->t_tid != this_tid) |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 215 | return ret; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 216 | while (!released && transaction->t_checkpoint_io_list) { |
| 217 | jh = transaction->t_checkpoint_io_list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | bh = jh2bh(jh); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 219 | if (!jbd_trylock_bh_state(bh)) { |
| 220 | jbd_sync_bh(journal, bh); |
| 221 | spin_lock(&journal->j_list_lock); |
| 222 | goto restart; |
| 223 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | if (buffer_locked(bh)) { |
Namhyung Kim | e4d5e3a | 2010-10-16 17:11:02 +0900 | [diff] [blame] | 225 | get_bh(bh); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | spin_unlock(&journal->j_list_lock); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 227 | jbd_unlock_bh_state(bh); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | wait_on_buffer(bh); |
| 229 | /* the journal_head may have gone by now */ |
| 230 | BUFFER_TRACE(bh, "brelse"); |
| 231 | __brelse(bh); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 232 | spin_lock(&journal->j_list_lock); |
| 233 | goto restart; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | } |
Hidehiro Kawai | 9f818b4 | 2008-10-22 14:15:02 -0700 | [diff] [blame] | 235 | if (unlikely(buffer_write_io_error(bh))) |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 236 | ret = -EIO; |
| 237 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | /* |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 239 | * Now in whatever state the buffer currently is, we know that |
| 240 | * it has been written out and so we can drop it from the list |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | */ |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 242 | released = __journal_remove_checkpoint(jh); |
| 243 | jbd_unlock_bh_state(bh); |
| 244 | journal_remove_journal_head(bh); |
| 245 | __brelse(bh); |
| 246 | } |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 247 | |
| 248 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | } |
| 250 | |
| 251 | #define NR_BATCH 64 |
| 252 | |
| 253 | static void |
| 254 | __flush_batch(journal_t *journal, struct buffer_head **bhs, int *batch_count) |
| 255 | { |
| 256 | int i; |
| 257 | |
Christoph Hellwig | 9cb569d | 2010-08-11 17:06:24 +0200 | [diff] [blame] | 258 | for (i = 0; i < *batch_count; i++) |
| 259 | write_dirty_buffer(bhs[i], WRITE); |
| 260 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | for (i = 0; i < *batch_count; i++) { |
| 262 | struct buffer_head *bh = bhs[i]; |
| 263 | clear_buffer_jwrite(bh); |
| 264 | BUFFER_TRACE(bh, "brelse"); |
| 265 | __brelse(bh); |
| 266 | } |
| 267 | *batch_count = 0; |
| 268 | } |
| 269 | |
| 270 | /* |
| 271 | * Try to flush one buffer from the checkpoint list to disk. |
| 272 | * |
| 273 | * Return 1 if something happened which requires us to abort the current |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 274 | * scan of the checkpoint list. Return <0 if the buffer has failed to |
| 275 | * be written out. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 276 | * |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 277 | * Called with j_list_lock held and drops it if 1 is returned |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 278 | * Called under jbd_lock_bh_state(jh2bh(jh)), and drops it |
| 279 | */ |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 280 | static int __process_buffer(journal_t *journal, struct journal_head *jh, |
| 281 | struct buffer_head **bhs, int *batch_count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 282 | { |
| 283 | struct buffer_head *bh = jh2bh(jh); |
| 284 | int ret = 0; |
| 285 | |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 286 | if (buffer_locked(bh)) { |
Namhyung Kim | e4d5e3a | 2010-10-16 17:11:02 +0900 | [diff] [blame] | 287 | get_bh(bh); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 288 | spin_unlock(&journal->j_list_lock); |
| 289 | jbd_unlock_bh_state(bh); |
| 290 | wait_on_buffer(bh); |
| 291 | /* the journal_head may have gone by now */ |
| 292 | BUFFER_TRACE(bh, "brelse"); |
| 293 | __brelse(bh); |
| 294 | ret = 1; |
| 295 | } else if (jh->b_transaction != NULL) { |
| 296 | transaction_t *t = jh->b_transaction; |
| 297 | tid_t tid = t->t_tid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 299 | spin_unlock(&journal->j_list_lock); |
| 300 | jbd_unlock_bh_state(bh); |
| 301 | log_start_commit(journal, tid); |
| 302 | log_wait_commit(journal, tid); |
| 303 | ret = 1; |
| 304 | } else if (!buffer_dirty(bh)) { |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 305 | ret = 1; |
Hidehiro Kawai | 9f818b4 | 2008-10-22 14:15:02 -0700 | [diff] [blame] | 306 | if (unlikely(buffer_write_io_error(bh))) |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 307 | ret = -EIO; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 308 | J_ASSERT_JH(jh, !buffer_jbddirty(bh)); |
| 309 | BUFFER_TRACE(bh, "remove from checkpoint"); |
| 310 | __journal_remove_checkpoint(jh); |
| 311 | spin_unlock(&journal->j_list_lock); |
| 312 | jbd_unlock_bh_state(bh); |
| 313 | journal_remove_journal_head(bh); |
| 314 | __brelse(bh); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 315 | } else { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | /* |
| 317 | * Important: we are about to write the buffer, and |
| 318 | * possibly block, while still holding the journal lock. |
| 319 | * We cannot afford to let the transaction logic start |
| 320 | * messing around with this buffer before we write it to |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 321 | * disk, as that would break recoverability. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | */ |
| 323 | BUFFER_TRACE(bh, "queue"); |
| 324 | get_bh(bh); |
| 325 | J_ASSERT_BH(bh, !buffer_jwrite(bh)); |
| 326 | set_buffer_jwrite(bh); |
| 327 | bhs[*batch_count] = bh; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 328 | __buffer_relink_io(jh); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | jbd_unlock_bh_state(bh); |
| 330 | (*batch_count)++; |
| 331 | if (*batch_count == NR_BATCH) { |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 332 | spin_unlock(&journal->j_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | __flush_batch(journal, bhs, batch_count); |
| 334 | ret = 1; |
| 335 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | } |
| 337 | return ret; |
| 338 | } |
| 339 | |
| 340 | /* |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 341 | * Perform an actual checkpoint. We take the first transaction on the |
| 342 | * list of transactions to be checkpointed and send all its buffers |
| 343 | * to disk. We submit larger chunks of data at once. |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 344 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 345 | * The journal should be locked before calling this function. |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 346 | * Called with j_checkpoint_mutex held. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | */ |
| 348 | int log_do_checkpoint(journal_t *journal) |
| 349 | { |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 350 | transaction_t *transaction; |
| 351 | tid_t this_tid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | int result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | |
| 354 | jbd_debug(1, "Start checkpoint\n"); |
| 355 | |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 356 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 357 | * First thing: if there are any transactions in the log which |
| 358 | * don't need checkpointing, just eliminate them from the |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 359 | * journal straight away. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | */ |
| 361 | result = cleanup_journal_tail(journal); |
Lukas Czerner | 99cb1a3 | 2011-05-23 18:33:02 +0200 | [diff] [blame] | 362 | trace_jbd_checkpoint(journal, result); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | jbd_debug(1, "cleanup_journal_tail returned %d\n", result); |
| 364 | if (result <= 0) |
| 365 | return result; |
| 366 | |
| 367 | /* |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 368 | * OK, we need to start writing disk blocks. Take one transaction |
| 369 | * and write it. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 370 | */ |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 371 | result = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | spin_lock(&journal->j_list_lock); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 373 | if (!journal->j_checkpoint_transactions) |
| 374 | goto out; |
| 375 | transaction = journal->j_checkpoint_transactions; |
| 376 | this_tid = transaction->t_tid; |
| 377 | restart: |
| 378 | /* |
| 379 | * If someone cleaned up this transaction while we slept, we're |
| 380 | * done (maybe it's a new transaction, but it fell at the same |
| 381 | * address). |
| 382 | */ |
| 383 | if (journal->j_checkpoint_transactions == transaction && |
| 384 | transaction->t_tid == this_tid) { |
| 385 | int batch_count = 0; |
| 386 | struct buffer_head *bhs[NR_BATCH]; |
| 387 | struct journal_head *jh; |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 388 | int retry = 0, err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 390 | while (!retry && transaction->t_checkpoint_list) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 391 | struct buffer_head *bh; |
| 392 | |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 393 | jh = transaction->t_checkpoint_list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | bh = jh2bh(jh); |
| 395 | if (!jbd_trylock_bh_state(bh)) { |
| 396 | jbd_sync_bh(journal, bh); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | retry = 1; |
| 398 | break; |
| 399 | } |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 400 | retry = __process_buffer(journal, jh, bhs,&batch_count); |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 401 | if (retry < 0 && !result) |
| 402 | result = retry; |
Nick Piggin | 95c354f | 2008-01-30 13:31:20 +0100 | [diff] [blame] | 403 | if (!retry && (need_resched() || |
| 404 | spin_needbreak(&journal->j_list_lock))) { |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 405 | spin_unlock(&journal->j_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | retry = 1; |
| 407 | break; |
| 408 | } |
Jan Kara | f93ea41 | 2006-01-06 00:19:55 -0800 | [diff] [blame] | 409 | } |
| 410 | |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 411 | if (batch_count) { |
| 412 | if (!retry) { |
| 413 | spin_unlock(&journal->j_list_lock); |
| 414 | retry = 1; |
| 415 | } |
| 416 | __flush_batch(journal, bhs, &batch_count); |
| 417 | } |
| 418 | |
| 419 | if (retry) { |
| 420 | spin_lock(&journal->j_list_lock); |
| 421 | goto restart; |
| 422 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 423 | /* |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 424 | * Now we have cleaned up the first transaction's checkpoint |
| 425 | * list. Let's clean up the second one |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 426 | */ |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 427 | err = __wait_cp_io(journal, transaction); |
| 428 | if (!result) |
| 429 | result = err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 430 | } |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 431 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 432 | spin_unlock(&journal->j_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | if (result < 0) |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 434 | journal_abort(journal, result); |
| 435 | else |
| 436 | result = cleanup_journal_tail(journal); |
| 437 | |
| 438 | return (result < 0) ? result : 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | } |
| 440 | |
| 441 | /* |
| 442 | * Check the list of checkpoint transactions for the journal to see if |
| 443 | * we have already got rid of any since the last update of the log tail |
| 444 | * in the journal superblock. If so, we can instantly roll the |
| 445 | * superblock forward to remove those transactions from the log. |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 446 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | * Return <0 on error, 0 on success, 1 if there was nothing to clean up. |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 448 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 449 | * Called with the journal lock held. |
| 450 | * |
| 451 | * This is the only part of the journaling code which really needs to be |
| 452 | * aware of transaction aborts. Checkpointing involves writing to the |
| 453 | * main filesystem area rather than to the journal, so it can proceed |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 454 | * even in abort state, but we must not update the super block if |
| 455 | * checkpointing may have failed. Otherwise, we would lose some metadata |
| 456 | * buffers which should be written-back to the filesystem. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | */ |
| 458 | |
| 459 | int cleanup_journal_tail(journal_t *journal) |
| 460 | { |
| 461 | transaction_t * transaction; |
| 462 | tid_t first_tid; |
Jan Kara | 9c28cbc | 2009-08-03 19:21:00 +0200 | [diff] [blame] | 463 | unsigned int blocknr, freed; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | |
Hidehiro Kawai | 4afe978 | 2008-10-22 14:15:00 -0700 | [diff] [blame] | 465 | if (is_journal_aborted(journal)) |
| 466 | return 1; |
| 467 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 468 | /* OK, work out the oldest transaction remaining in the log, and |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 469 | * the log block it starts at. |
| 470 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | * If the log is now empty, we need to work out which is the |
| 472 | * next transaction ID we will write, and where it will |
| 473 | * start. */ |
| 474 | |
| 475 | spin_lock(&journal->j_state_lock); |
| 476 | spin_lock(&journal->j_list_lock); |
| 477 | transaction = journal->j_checkpoint_transactions; |
| 478 | if (transaction) { |
| 479 | first_tid = transaction->t_tid; |
| 480 | blocknr = transaction->t_log_start; |
| 481 | } else if ((transaction = journal->j_committing_transaction) != NULL) { |
| 482 | first_tid = transaction->t_tid; |
| 483 | blocknr = transaction->t_log_start; |
| 484 | } else if ((transaction = journal->j_running_transaction) != NULL) { |
| 485 | first_tid = transaction->t_tid; |
| 486 | blocknr = journal->j_head; |
| 487 | } else { |
| 488 | first_tid = journal->j_transaction_sequence; |
| 489 | blocknr = journal->j_head; |
| 490 | } |
| 491 | spin_unlock(&journal->j_list_lock); |
| 492 | J_ASSERT(blocknr != 0); |
| 493 | |
| 494 | /* If the oldest pinned transaction is at the tail of the log |
| 495 | already then there's not much we can do right now. */ |
| 496 | if (journal->j_tail_sequence == first_tid) { |
| 497 | spin_unlock(&journal->j_state_lock); |
| 498 | return 1; |
| 499 | } |
| 500 | |
| 501 | /* OK, update the superblock to recover the freed space. |
| 502 | * Physical blocks come first: have we wrapped beyond the end of |
| 503 | * the log? */ |
| 504 | freed = blocknr - journal->j_tail; |
| 505 | if (blocknr < journal->j_tail) |
| 506 | freed = freed + journal->j_last - journal->j_first; |
| 507 | |
Lukas Czerner | 99cb1a3 | 2011-05-23 18:33:02 +0200 | [diff] [blame] | 508 | trace_jbd_cleanup_journal_tail(journal, first_tid, blocknr, freed); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 509 | jbd_debug(1, |
Jan Kara | 9c28cbc | 2009-08-03 19:21:00 +0200 | [diff] [blame] | 510 | "Cleaning journal tail from %d to %d (offset %u), " |
| 511 | "freeing %u\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 512 | journal->j_tail_sequence, first_tid, blocknr, freed); |
| 513 | |
| 514 | journal->j_free += freed; |
| 515 | journal->j_tail_sequence = first_tid; |
| 516 | journal->j_tail = blocknr; |
| 517 | spin_unlock(&journal->j_state_lock); |
| 518 | if (!(journal->j_flags & JFS_ABORT)) |
| 519 | journal_update_superblock(journal, 1); |
| 520 | return 0; |
| 521 | } |
| 522 | |
| 523 | |
| 524 | /* Checkpoint list management */ |
| 525 | |
| 526 | /* |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 527 | * journal_clean_one_cp_list |
Jan Kara | f93ea41 | 2006-01-06 00:19:55 -0800 | [diff] [blame] | 528 | * |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 529 | * Find all the written-back checkpoint buffers in the given list and release them. |
Jan Kara | f93ea41 | 2006-01-06 00:19:55 -0800 | [diff] [blame] | 530 | * |
| 531 | * Called with the journal locked. |
| 532 | * Called with j_list_lock held. |
Mark Fasheh | 7c8903f | 2006-02-14 13:53:03 -0800 | [diff] [blame] | 533 | * Returns number of bufers reaped (for debug) |
Jan Kara | f93ea41 | 2006-01-06 00:19:55 -0800 | [diff] [blame] | 534 | */ |
| 535 | |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 536 | static int journal_clean_one_cp_list(struct journal_head *jh, int *released) |
| 537 | { |
| 538 | struct journal_head *last_jh; |
| 539 | struct journal_head *next_jh = jh; |
| 540 | int ret, freed = 0; |
| 541 | |
| 542 | *released = 0; |
| 543 | if (!jh) |
| 544 | return 0; |
| 545 | |
Dave Kleikamp | e9ad562 | 2006-09-27 01:49:35 -0700 | [diff] [blame] | 546 | last_jh = jh->b_cpprev; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 547 | do { |
| 548 | jh = next_jh; |
| 549 | next_jh = jh->b_cpnext; |
| 550 | /* Use trylock because of the ranking */ |
| 551 | if (jbd_trylock_bh_state(jh2bh(jh))) { |
| 552 | ret = __try_to_free_cp_buf(jh); |
| 553 | if (ret) { |
| 554 | freed++; |
| 555 | if (ret == 2) { |
| 556 | *released = 1; |
| 557 | return freed; |
| 558 | } |
| 559 | } |
| 560 | } |
| 561 | /* |
| 562 | * This function only frees up some memory |
| 563 | * if possible so we dont have an obligation |
| 564 | * to finish processing. Bail out if preemption |
| 565 | * requested: |
| 566 | */ |
| 567 | if (need_resched()) |
| 568 | return freed; |
| 569 | } while (jh != last_jh); |
| 570 | |
| 571 | return freed; |
| 572 | } |
| 573 | |
| 574 | /* |
| 575 | * journal_clean_checkpoint_list |
| 576 | * |
| 577 | * Find all the written-back checkpoint buffers in the journal and release them. |
| 578 | * |
| 579 | * Called with the journal locked. |
| 580 | * Called with j_list_lock held. |
| 581 | * Returns number of buffers reaped (for debug) |
| 582 | */ |
| 583 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | int __journal_clean_checkpoint_list(journal_t *journal) |
| 585 | { |
| 586 | transaction_t *transaction, *last_transaction, *next_transaction; |
Mark Fasheh | 7c8903f | 2006-02-14 13:53:03 -0800 | [diff] [blame] | 587 | int ret = 0; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 588 | int released; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 589 | |
| 590 | transaction = journal->j_checkpoint_transactions; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 591 | if (!transaction) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 592 | goto out; |
| 593 | |
| 594 | last_transaction = transaction->t_cpprev; |
| 595 | next_transaction = transaction; |
| 596 | do { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 597 | transaction = next_transaction; |
| 598 | next_transaction = transaction->t_cpnext; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 599 | ret += journal_clean_one_cp_list(transaction-> |
| 600 | t_checkpoint_list, &released); |
| 601 | /* |
| 602 | * This function only frees up some memory if possible so we |
| 603 | * dont have an obligation to finish processing. Bail out if |
| 604 | * preemption requested: |
| 605 | */ |
| 606 | if (need_resched()) |
| 607 | goto out; |
| 608 | if (released) |
| 609 | continue; |
| 610 | /* |
| 611 | * It is essential that we are as careful as in the case of |
| 612 | * t_checkpoint_list with removing the buffer from the list as |
| 613 | * we can possibly see not yet submitted buffers on io_list |
| 614 | */ |
| 615 | ret += journal_clean_one_cp_list(transaction-> |
| 616 | t_checkpoint_io_list, &released); |
| 617 | if (need_resched()) |
| 618 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 619 | } while (transaction != last_transaction); |
| 620 | out: |
| 621 | return ret; |
| 622 | } |
| 623 | |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 624 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 625 | * journal_remove_checkpoint: called after a buffer has been committed |
| 626 | * to disk (either by being write-back flushed to disk, or being |
| 627 | * committed to the log). |
| 628 | * |
| 629 | * We cannot safely clean a transaction out of the log until all of the |
| 630 | * buffer updates committed in that transaction have safely been stored |
| 631 | * elsewhere on disk. To achieve this, all of the buffers in a |
| 632 | * transaction need to be maintained on the transaction's checkpoint |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 633 | * lists until they have been rewritten, at which point this function is |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 634 | * called to remove the buffer from the existing transaction's |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 635 | * checkpoint lists. |
| 636 | * |
| 637 | * The function returns 1 if it frees the transaction, 0 otherwise. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | * |
| 639 | * This function is called with the journal locked. |
| 640 | * This function is called with j_list_lock held. |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 641 | * This function is called with jbd_lock_bh_state(jh2bh(jh)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 642 | */ |
| 643 | |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 644 | int __journal_remove_checkpoint(struct journal_head *jh) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 645 | { |
| 646 | transaction_t *transaction; |
| 647 | journal_t *journal; |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 648 | int ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 649 | |
| 650 | JBUFFER_TRACE(jh, "entry"); |
| 651 | |
| 652 | if ((transaction = jh->b_cp_transaction) == NULL) { |
| 653 | JBUFFER_TRACE(jh, "not on transaction"); |
| 654 | goto out; |
| 655 | } |
| 656 | journal = transaction->t_journal; |
| 657 | |
| 658 | __buffer_unlink(jh); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 659 | jh->b_cp_transaction = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 660 | |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 661 | if (transaction->t_checkpoint_list != NULL || |
| 662 | transaction->t_checkpoint_io_list != NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 663 | goto out; |
| 664 | JBUFFER_TRACE(jh, "transaction has no more buffers"); |
| 665 | |
| 666 | /* |
| 667 | * There is one special case to worry about: if we have just pulled the |
Jan Kara | d4beaf4 | 2007-12-04 23:45:27 -0800 | [diff] [blame] | 668 | * buffer off a running or committing transaction's checkpoing list, |
| 669 | * then even if the checkpoint list is empty, the transaction obviously |
| 670 | * cannot be dropped! |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | * |
Jan Kara | d4beaf4 | 2007-12-04 23:45:27 -0800 | [diff] [blame] | 672 | * The locking here around t_state is a bit sleazy. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 673 | * See the comment at the end of journal_commit_transaction(). |
| 674 | */ |
Jan Kara | d4beaf4 | 2007-12-04 23:45:27 -0800 | [diff] [blame] | 675 | if (transaction->t_state != T_FINISHED) { |
| 676 | JBUFFER_TRACE(jh, "belongs to running/committing transaction"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 677 | goto out; |
| 678 | } |
| 679 | |
| 680 | /* OK, that was the last buffer for the transaction: we can now |
| 681 | safely remove this transaction from the log */ |
| 682 | |
| 683 | __journal_drop_transaction(journal, transaction); |
| 684 | |
| 685 | /* Just in case anybody was waiting for more transactions to be |
| 686 | checkpointed... */ |
| 687 | wake_up(&journal->j_wait_logspace); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 688 | ret = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 689 | out: |
| 690 | JBUFFER_TRACE(jh, "exit"); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 691 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 692 | } |
| 693 | |
| 694 | /* |
| 695 | * journal_insert_checkpoint: put a committed buffer onto a checkpoint |
| 696 | * list so that we know when it is safe to clean the transaction out of |
| 697 | * the log. |
| 698 | * |
| 699 | * Called with the journal locked. |
| 700 | * Called with j_list_lock held. |
| 701 | */ |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 702 | void __journal_insert_checkpoint(struct journal_head *jh, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 703 | transaction_t *transaction) |
| 704 | { |
| 705 | JBUFFER_TRACE(jh, "entry"); |
| 706 | J_ASSERT_JH(jh, buffer_dirty(jh2bh(jh)) || buffer_jbddirty(jh2bh(jh))); |
| 707 | J_ASSERT_JH(jh, jh->b_cp_transaction == NULL); |
| 708 | |
| 709 | jh->b_cp_transaction = transaction; |
| 710 | |
| 711 | if (!transaction->t_checkpoint_list) { |
| 712 | jh->b_cpnext = jh->b_cpprev = jh; |
| 713 | } else { |
| 714 | jh->b_cpnext = transaction->t_checkpoint_list; |
| 715 | jh->b_cpprev = transaction->t_checkpoint_list->b_cpprev; |
| 716 | jh->b_cpprev->b_cpnext = jh; |
| 717 | jh->b_cpnext->b_cpprev = jh; |
| 718 | } |
| 719 | transaction->t_checkpoint_list = jh; |
| 720 | } |
| 721 | |
| 722 | /* |
| 723 | * We've finished with this transaction structure: adios... |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 724 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 725 | * The transaction must have no links except for the checkpoint by this |
| 726 | * point. |
| 727 | * |
| 728 | * Called with the journal locked. |
| 729 | * Called with j_list_lock held. |
| 730 | */ |
| 731 | |
| 732 | void __journal_drop_transaction(journal_t *journal, transaction_t *transaction) |
| 733 | { |
| 734 | assert_spin_locked(&journal->j_list_lock); |
| 735 | if (transaction->t_cpnext) { |
| 736 | transaction->t_cpnext->t_cpprev = transaction->t_cpprev; |
| 737 | transaction->t_cpprev->t_cpnext = transaction->t_cpnext; |
| 738 | if (journal->j_checkpoint_transactions == transaction) |
| 739 | journal->j_checkpoint_transactions = |
| 740 | transaction->t_cpnext; |
| 741 | if (journal->j_checkpoint_transactions == transaction) |
| 742 | journal->j_checkpoint_transactions = NULL; |
| 743 | } |
| 744 | |
| 745 | J_ASSERT(transaction->t_state == T_FINISHED); |
| 746 | J_ASSERT(transaction->t_buffers == NULL); |
| 747 | J_ASSERT(transaction->t_sync_datalist == NULL); |
| 748 | J_ASSERT(transaction->t_forget == NULL); |
| 749 | J_ASSERT(transaction->t_iobuf_list == NULL); |
| 750 | J_ASSERT(transaction->t_shadow_list == NULL); |
| 751 | J_ASSERT(transaction->t_log_list == NULL); |
| 752 | J_ASSERT(transaction->t_checkpoint_list == NULL); |
Jan Kara | 78ce89c | 2006-06-23 02:06:05 -0700 | [diff] [blame] | 753 | J_ASSERT(transaction->t_checkpoint_io_list == NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 754 | J_ASSERT(transaction->t_updates == 0); |
| 755 | J_ASSERT(journal->j_committing_transaction != transaction); |
| 756 | J_ASSERT(journal->j_running_transaction != transaction); |
| 757 | |
Lukas Czerner | 99cb1a3 | 2011-05-23 18:33:02 +0200 | [diff] [blame] | 758 | trace_jbd_drop_transaction(journal, transaction); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 759 | jbd_debug(1, "Dropping transaction %d, all done\n", transaction->t_tid); |
| 760 | kfree(transaction); |
| 761 | } |