Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1 | /* |
Uwe Kleine-König | 5886269 | 2007-05-09 07:51:49 +0200 | [diff] [blame] | 2 | * linux/fs/jbd2/transaction.c |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 3 | * |
| 4 | * Written by Stephen C. Tweedie <sct@redhat.com>, 1998 |
| 5 | * |
| 6 | * Copyright 1998 Red Hat corp --- 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 | * |
| 12 | * Generic filesystem transaction handling code; part of the ext2fs |
| 13 | * journaling system. |
| 14 | * |
| 15 | * This file manages transactions (compound commits managed by the |
| 16 | * journaling code) and handles (individual atomic operations by the |
| 17 | * filesystem). |
| 18 | */ |
| 19 | |
| 20 | #include <linux/time.h> |
| 21 | #include <linux/fs.h> |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 22 | #include <linux/jbd2.h> |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 23 | #include <linux/errno.h> |
| 24 | #include <linux/slab.h> |
| 25 | #include <linux/timer.h> |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 26 | #include <linux/mm.h> |
| 27 | #include <linux/highmem.h> |
Josef Bacik | e07f718 | 2008-11-26 01:14:26 -0500 | [diff] [blame] | 28 | #include <linux/hrtimer.h> |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 29 | #include <linux/backing-dev.h> |
Randy Dunlap | 4470575 | 2011-10-27 04:05:13 -0400 | [diff] [blame] | 30 | #include <linux/bug.h> |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 31 | #include <linux/module.h> |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 32 | |
Adrian Bunk | 7ddae86 | 2006-12-06 20:38:27 -0800 | [diff] [blame] | 33 | static void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh); |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 34 | static void __jbd2_journal_unfile_buffer(struct journal_head *jh); |
Adrian Bunk | 7ddae86 | 2006-12-06 20:38:27 -0800 | [diff] [blame] | 35 | |
Yongqiang Yang | 0c2022e | 2012-02-20 17:53:02 -0500 | [diff] [blame] | 36 | static struct kmem_cache *transaction_cache; |
| 37 | int __init jbd2_journal_init_transaction_cache(void) |
| 38 | { |
| 39 | J_ASSERT(!transaction_cache); |
| 40 | transaction_cache = kmem_cache_create("jbd2_transaction_s", |
| 41 | sizeof(transaction_t), |
| 42 | 0, |
| 43 | SLAB_HWCACHE_ALIGN|SLAB_TEMPORARY, |
| 44 | NULL); |
| 45 | if (transaction_cache) |
| 46 | return 0; |
| 47 | return -ENOMEM; |
| 48 | } |
| 49 | |
| 50 | void jbd2_journal_destroy_transaction_cache(void) |
| 51 | { |
| 52 | if (transaction_cache) { |
| 53 | kmem_cache_destroy(transaction_cache); |
| 54 | transaction_cache = NULL; |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | void jbd2_journal_free_transaction(transaction_t *transaction) |
| 59 | { |
| 60 | if (unlikely(ZERO_OR_NULL_PTR(transaction))) |
| 61 | return; |
| 62 | kmem_cache_free(transaction_cache, transaction); |
| 63 | } |
| 64 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 65 | /* |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 66 | * jbd2_get_transaction: obtain a new transaction_t object. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 67 | * |
| 68 | * Simply allocate and initialise a new transaction. Create it in |
| 69 | * RUNNING state and add it to the current journal (which should not |
| 70 | * have an existing running transaction: we only make a new transaction |
| 71 | * once we have started to commit the old one). |
| 72 | * |
| 73 | * Preconditions: |
| 74 | * The journal MUST be locked. We don't perform atomic mallocs on the |
| 75 | * new transaction and we can't block without protecting against other |
| 76 | * processes trying to touch the journal while it is in transition. |
| 77 | * |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 78 | */ |
| 79 | |
| 80 | static transaction_t * |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 81 | jbd2_get_transaction(journal_t *journal, transaction_t *transaction) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 82 | { |
| 83 | transaction->t_journal = journal; |
| 84 | transaction->t_state = T_RUNNING; |
Josef Bacik | e07f718 | 2008-11-26 01:14:26 -0500 | [diff] [blame] | 85 | transaction->t_start_time = ktime_get(); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 86 | transaction->t_tid = journal->j_transaction_sequence++; |
| 87 | transaction->t_expires = jiffies + journal->j_commit_interval; |
| 88 | spin_lock_init(&transaction->t_handle_lock); |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 89 | atomic_set(&transaction->t_updates, 0); |
| 90 | atomic_set(&transaction->t_outstanding_credits, 0); |
Theodore Ts'o | 8dd4204 | 2010-08-03 21:38:29 -0400 | [diff] [blame] | 91 | atomic_set(&transaction->t_handle_count, 0); |
Jan Kara | c851ed5 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 92 | INIT_LIST_HEAD(&transaction->t_inode_list); |
Theodore Ts'o | 3e624fc | 2008-10-16 20:00:24 -0400 | [diff] [blame] | 93 | INIT_LIST_HEAD(&transaction->t_private_list); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 94 | |
| 95 | /* Set up the commit timer for the new transaction. */ |
Andreas Dilger | b1f485f | 2009-08-10 22:51:53 -0400 | [diff] [blame] | 96 | journal->j_commit_timer.expires = round_jiffies_up(transaction->t_expires); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 97 | add_timer(&journal->j_commit_timer); |
| 98 | |
| 99 | J_ASSERT(journal->j_running_transaction == NULL); |
| 100 | journal->j_running_transaction = transaction; |
Johann Lombardi | 8e85fb3 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 101 | transaction->t_max_wait = 0; |
| 102 | transaction->t_start = jiffies; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 103 | |
| 104 | return transaction; |
| 105 | } |
| 106 | |
| 107 | /* |
| 108 | * Handle management. |
| 109 | * |
| 110 | * A handle_t is an object which represents a single atomic update to a |
| 111 | * filesystem, and which tracks all of the modifications which form part |
| 112 | * of that one update. |
| 113 | */ |
| 114 | |
| 115 | /* |
Tao Ma | 28e35e4 | 2011-05-22 21:45:26 -0400 | [diff] [blame] | 116 | * Update transaction's maximum wait time, if debugging is enabled. |
Theodore Ts'o | 6d0bf00 | 2010-08-09 17:28:38 -0400 | [diff] [blame] | 117 | * |
| 118 | * In order for t_max_wait to be reliable, it must be protected by a |
| 119 | * lock. But doing so will mean that start_this_handle() can not be |
| 120 | * run in parallel on SMP systems, which limits our scalability. So |
| 121 | * unless debugging is enabled, we no longer update t_max_wait, which |
| 122 | * means that maximum wait time reported by the jbd2_run_stats |
| 123 | * tracepoint will always be zero. |
| 124 | */ |
Tao Ma | 28e35e4 | 2011-05-22 21:45:26 -0400 | [diff] [blame] | 125 | static inline void update_t_max_wait(transaction_t *transaction, |
| 126 | unsigned long ts) |
Theodore Ts'o | 6d0bf00 | 2010-08-09 17:28:38 -0400 | [diff] [blame] | 127 | { |
| 128 | #ifdef CONFIG_JBD2_DEBUG |
Theodore Ts'o | 6d0bf00 | 2010-08-09 17:28:38 -0400 | [diff] [blame] | 129 | if (jbd2_journal_enable_debug && |
| 130 | time_after(transaction->t_start, ts)) { |
| 131 | ts = jbd2_time_diff(ts, transaction->t_start); |
| 132 | spin_lock(&transaction->t_handle_lock); |
| 133 | if (ts > transaction->t_max_wait) |
| 134 | transaction->t_max_wait = ts; |
| 135 | spin_unlock(&transaction->t_handle_lock); |
| 136 | } |
| 137 | #endif |
| 138 | } |
| 139 | |
| 140 | /* |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 141 | * start_this_handle: Given a handle, deal with any locking or stalling |
| 142 | * needed to make sure that there is enough journal space for the handle |
| 143 | * to begin. Attach the handle to a transaction and set up the |
| 144 | * transaction's buffer credits. |
| 145 | */ |
| 146 | |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 147 | static int start_this_handle(journal_t *journal, handle_t *handle, |
Dan Carpenter | d2159fb | 2011-09-04 10:20:14 -0400 | [diff] [blame] | 148 | gfp_t gfp_mask) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 149 | { |
Theodore Ts'o | e447183 | 2011-02-12 08:18:24 -0500 | [diff] [blame] | 150 | transaction_t *transaction, *new_transaction = NULL; |
| 151 | tid_t tid; |
| 152 | int needed, need_to_start; |
| 153 | int nblocks = handle->h_buffer_credits; |
Tao Ma | 28e35e4 | 2011-05-22 21:45:26 -0400 | [diff] [blame] | 154 | unsigned long ts = jiffies; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 155 | |
| 156 | if (nblocks > journal->j_max_transaction_buffers) { |
Eryu Guan | f2a4452 | 2011-11-01 19:09:18 -0400 | [diff] [blame] | 157 | printk(KERN_ERR "JBD2: %s wants too many credits (%d > %d)\n", |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 158 | current->comm, nblocks, |
| 159 | journal->j_max_transaction_buffers); |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 160 | return -ENOSPC; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 161 | } |
| 162 | |
| 163 | alloc_transaction: |
| 164 | if (!journal->j_running_transaction) { |
Wanlong Gao | b2f4edb | 2012-06-01 00:10:32 -0400 | [diff] [blame] | 165 | new_transaction = kmem_cache_zalloc(transaction_cache, |
| 166 | gfp_mask); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 167 | if (!new_transaction) { |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 168 | /* |
| 169 | * If __GFP_FS is not present, then we may be |
| 170 | * being called from inside the fs writeback |
| 171 | * layer, so we MUST NOT fail. Since |
| 172 | * __GFP_NOFAIL is going away, we will arrange |
| 173 | * to retry the allocation ourselves. |
| 174 | */ |
| 175 | if ((gfp_mask & __GFP_FS) == 0) { |
| 176 | congestion_wait(BLK_RW_ASYNC, HZ/50); |
| 177 | goto alloc_transaction; |
| 178 | } |
| 179 | return -ENOMEM; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 180 | } |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 181 | } |
| 182 | |
| 183 | jbd_debug(3, "New handle %p going live.\n", handle); |
| 184 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 185 | /* |
| 186 | * We need to hold j_state_lock until t_updates has been incremented, |
| 187 | * for proper journal barrier handling |
| 188 | */ |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 189 | repeat: |
| 190 | read_lock(&journal->j_state_lock); |
Theodore Ts'o | 5c2178e | 2010-10-27 21:30:04 -0400 | [diff] [blame] | 191 | BUG_ON(journal->j_flags & JBD2_UNMOUNT); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 192 | if (is_journal_aborted(journal) || |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 193 | (journal->j_errno != 0 && !(journal->j_flags & JBD2_ACK_ERR))) { |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 194 | read_unlock(&journal->j_state_lock); |
Yongqiang Yang | 0c2022e | 2012-02-20 17:53:02 -0500 | [diff] [blame] | 195 | jbd2_journal_free_transaction(new_transaction); |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 196 | return -EROFS; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 197 | } |
| 198 | |
| 199 | /* Wait on the journal's transaction barrier if necessary */ |
| 200 | if (journal->j_barrier_count) { |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 201 | read_unlock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 202 | wait_event(journal->j_wait_transaction_locked, |
| 203 | journal->j_barrier_count == 0); |
| 204 | goto repeat; |
| 205 | } |
| 206 | |
| 207 | if (!journal->j_running_transaction) { |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 208 | read_unlock(&journal->j_state_lock); |
| 209 | if (!new_transaction) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 210 | goto alloc_transaction; |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 211 | write_lock(&journal->j_state_lock); |
| 212 | if (!journal->j_running_transaction) { |
| 213 | jbd2_get_transaction(journal, new_transaction); |
| 214 | new_transaction = NULL; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 215 | } |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 216 | write_unlock(&journal->j_state_lock); |
| 217 | goto repeat; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 218 | } |
| 219 | |
| 220 | transaction = journal->j_running_transaction; |
| 221 | |
| 222 | /* |
| 223 | * If the current transaction is locked down for commit, wait for the |
| 224 | * lock to be released. |
| 225 | */ |
| 226 | if (transaction->t_state == T_LOCKED) { |
| 227 | DEFINE_WAIT(wait); |
| 228 | |
| 229 | prepare_to_wait(&journal->j_wait_transaction_locked, |
| 230 | &wait, TASK_UNINTERRUPTIBLE); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 231 | read_unlock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 232 | schedule(); |
| 233 | finish_wait(&journal->j_wait_transaction_locked, &wait); |
| 234 | goto repeat; |
| 235 | } |
| 236 | |
| 237 | /* |
| 238 | * If there is not enough space left in the log to write all potential |
| 239 | * buffers requested by this operation, we need to stall pending a log |
| 240 | * checkpoint to free some more log space. |
| 241 | */ |
Theodore Ts'o | 8dd4204 | 2010-08-03 21:38:29 -0400 | [diff] [blame] | 242 | needed = atomic_add_return(nblocks, |
| 243 | &transaction->t_outstanding_credits); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 244 | |
| 245 | if (needed > journal->j_max_transaction_buffers) { |
| 246 | /* |
| 247 | * If the current transaction is already too large, then start |
| 248 | * to commit it: we can then go back and attach this handle to |
| 249 | * a new transaction. |
| 250 | */ |
| 251 | DEFINE_WAIT(wait); |
| 252 | |
| 253 | jbd_debug(2, "Handle %p starting new commit...\n", handle); |
Theodore Ts'o | 8dd4204 | 2010-08-03 21:38:29 -0400 | [diff] [blame] | 254 | atomic_sub(nblocks, &transaction->t_outstanding_credits); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 255 | prepare_to_wait(&journal->j_wait_transaction_locked, &wait, |
| 256 | TASK_UNINTERRUPTIBLE); |
Theodore Ts'o | e447183 | 2011-02-12 08:18:24 -0500 | [diff] [blame] | 257 | tid = transaction->t_tid; |
| 258 | need_to_start = !tid_geq(journal->j_commit_request, tid); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 259 | read_unlock(&journal->j_state_lock); |
Theodore Ts'o | e447183 | 2011-02-12 08:18:24 -0500 | [diff] [blame] | 260 | if (need_to_start) |
| 261 | jbd2_log_start_commit(journal, tid); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 262 | schedule(); |
| 263 | finish_wait(&journal->j_wait_transaction_locked, &wait); |
| 264 | goto repeat; |
| 265 | } |
| 266 | |
| 267 | /* |
| 268 | * The commit code assumes that it can get enough log space |
| 269 | * without forcing a checkpoint. This is *critical* for |
| 270 | * correctness: a checkpoint of a buffer which is also |
| 271 | * associated with a committing transaction creates a deadlock, |
| 272 | * so commit simply cannot force through checkpoints. |
| 273 | * |
| 274 | * We must therefore ensure the necessary space in the journal |
| 275 | * *before* starting to dirty potentially checkpointed buffers |
| 276 | * in the new transaction. |
| 277 | * |
| 278 | * The worst part is, any transaction currently committing can |
| 279 | * reduce the free space arbitrarily. Be careful to account for |
| 280 | * those buffers when checkpointing. |
| 281 | */ |
| 282 | |
| 283 | /* |
| 284 | * @@@ AKPM: This seems rather over-defensive. We're giving commit |
| 285 | * a _lot_ of headroom: 1/4 of the journal plus the size of |
| 286 | * the committing transaction. Really, we only need to give it |
| 287 | * committing_transaction->t_outstanding_credits plus "enough" for |
| 288 | * the log control blocks. |
Uwe Kleine-König | a34f0b3 | 2010-12-10 14:55:42 +0100 | [diff] [blame] | 289 | * Also, this test is inconsistent with the matching one in |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 290 | * jbd2_journal_extend(). |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 291 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 292 | if (__jbd2_log_space_left(journal) < jbd_space_needed(journal)) { |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 293 | jbd_debug(2, "Handle %p waiting for checkpoint...\n", handle); |
Theodore Ts'o | 8dd4204 | 2010-08-03 21:38:29 -0400 | [diff] [blame] | 294 | atomic_sub(nblocks, &transaction->t_outstanding_credits); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 295 | read_unlock(&journal->j_state_lock); |
| 296 | write_lock(&journal->j_state_lock); |
| 297 | if (__jbd2_log_space_left(journal) < jbd_space_needed(journal)) |
| 298 | __jbd2_log_wait_for_space(journal); |
| 299 | write_unlock(&journal->j_state_lock); |
| 300 | goto repeat; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 301 | } |
| 302 | |
| 303 | /* OK, account for the buffers that this operation expects to |
Theodore Ts'o | 8dd4204 | 2010-08-03 21:38:29 -0400 | [diff] [blame] | 304 | * use and add the handle to the running transaction. |
Theodore Ts'o | 8dd4204 | 2010-08-03 21:38:29 -0400 | [diff] [blame] | 305 | */ |
Tao Ma | 28e35e4 | 2011-05-22 21:45:26 -0400 | [diff] [blame] | 306 | update_t_max_wait(transaction, ts); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 307 | handle->h_transaction = transaction; |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 308 | atomic_inc(&transaction->t_updates); |
Theodore Ts'o | 8dd4204 | 2010-08-03 21:38:29 -0400 | [diff] [blame] | 309 | atomic_inc(&transaction->t_handle_count); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 310 | jbd_debug(4, "Handle %p given %d credits (total %d, free %d)\n", |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 311 | handle, nblocks, |
| 312 | atomic_read(&transaction->t_outstanding_credits), |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 313 | __jbd2_log_space_left(journal)); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 314 | read_unlock(&journal->j_state_lock); |
Jan Kara | 9599b0e | 2009-08-17 21:23:17 -0400 | [diff] [blame] | 315 | |
| 316 | lock_map_acquire(&handle->h_lockdep_map); |
Yongqiang Yang | 0c2022e | 2012-02-20 17:53:02 -0500 | [diff] [blame] | 317 | jbd2_journal_free_transaction(new_transaction); |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 318 | return 0; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 319 | } |
| 320 | |
Mingming Cao | 7b75106 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 321 | static struct lock_class_key jbd2_handle_key; |
| 322 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 323 | /* Allocate a new handle. This should probably be in a slab... */ |
| 324 | static handle_t *new_handle(int nblocks) |
| 325 | { |
Mingming Cao | af1e76d | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 326 | handle_t *handle = jbd2_alloc_handle(GFP_NOFS); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 327 | if (!handle) |
| 328 | return NULL; |
| 329 | memset(handle, 0, sizeof(*handle)); |
| 330 | handle->h_buffer_credits = nblocks; |
| 331 | handle->h_ref = 1; |
| 332 | |
Mingming Cao | 7b75106 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 333 | lockdep_init_map(&handle->h_lockdep_map, "jbd2_handle", |
| 334 | &jbd2_handle_key, 0); |
| 335 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 336 | return handle; |
| 337 | } |
| 338 | |
| 339 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 340 | * handle_t *jbd2_journal_start() - Obtain a new handle. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 341 | * @journal: Journal to start transaction on. |
| 342 | * @nblocks: number of block buffer we might modify |
| 343 | * |
| 344 | * We make sure that the transaction can guarantee at least nblocks of |
| 345 | * modified buffers in the log. We block until the log can guarantee |
| 346 | * that much space. |
| 347 | * |
| 348 | * This function is visible to journal users (like ext3fs), so is not |
| 349 | * called with the journal already locked. |
| 350 | * |
Eryu Guan | c867516 | 2011-05-24 17:09:58 -0400 | [diff] [blame] | 351 | * Return a pointer to a newly allocated handle, or an ERR_PTR() value |
| 352 | * on failure. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 353 | */ |
Dan Carpenter | d2159fb | 2011-09-04 10:20:14 -0400 | [diff] [blame] | 354 | handle_t *jbd2__journal_start(journal_t *journal, int nblocks, gfp_t gfp_mask) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 355 | { |
| 356 | handle_t *handle = journal_current_handle(); |
| 357 | int err; |
| 358 | |
| 359 | if (!journal) |
| 360 | return ERR_PTR(-EROFS); |
| 361 | |
| 362 | if (handle) { |
| 363 | J_ASSERT(handle->h_transaction->t_journal == journal); |
| 364 | handle->h_ref++; |
| 365 | return handle; |
| 366 | } |
| 367 | |
| 368 | handle = new_handle(nblocks); |
| 369 | if (!handle) |
| 370 | return ERR_PTR(-ENOMEM); |
| 371 | |
| 372 | current->journal_info = handle; |
| 373 | |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 374 | err = start_this_handle(journal, handle, gfp_mask); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 375 | if (err < 0) { |
Mingming Cao | af1e76d | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 376 | jbd2_free_handle(handle); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 377 | current->journal_info = NULL; |
| 378 | handle = ERR_PTR(err); |
| 379 | } |
| 380 | return handle; |
| 381 | } |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 382 | EXPORT_SYMBOL(jbd2__journal_start); |
| 383 | |
| 384 | |
| 385 | handle_t *jbd2_journal_start(journal_t *journal, int nblocks) |
| 386 | { |
| 387 | return jbd2__journal_start(journal, nblocks, GFP_NOFS); |
| 388 | } |
| 389 | EXPORT_SYMBOL(jbd2_journal_start); |
| 390 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 391 | |
| 392 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 393 | * int jbd2_journal_extend() - extend buffer credits. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 394 | * @handle: handle to 'extend' |
| 395 | * @nblocks: nr blocks to try to extend by. |
| 396 | * |
| 397 | * Some transactions, such as large extends and truncates, can be done |
| 398 | * atomically all at once or in several stages. The operation requests |
| 399 | * a credit for a number of buffer modications in advance, but can |
| 400 | * extend its credit if it needs more. |
| 401 | * |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 402 | * jbd2_journal_extend tries to give the running handle more buffer credits. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 403 | * It does not guarantee that allocation - this is a best-effort only. |
| 404 | * The calling process MUST be able to deal cleanly with a failure to |
| 405 | * extend here. |
| 406 | * |
| 407 | * Return 0 on success, non-zero on failure. |
| 408 | * |
| 409 | * return code < 0 implies an error |
| 410 | * return code > 0 implies normal transaction-full status. |
| 411 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 412 | int jbd2_journal_extend(handle_t *handle, int nblocks) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 413 | { |
| 414 | transaction_t *transaction = handle->h_transaction; |
| 415 | journal_t *journal = transaction->t_journal; |
| 416 | int result; |
| 417 | int wanted; |
| 418 | |
| 419 | result = -EIO; |
| 420 | if (is_handle_aborted(handle)) |
| 421 | goto out; |
| 422 | |
| 423 | result = 1; |
| 424 | |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 425 | read_lock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 426 | |
| 427 | /* Don't extend a locked-down transaction! */ |
| 428 | if (handle->h_transaction->t_state != T_RUNNING) { |
| 429 | jbd_debug(3, "denied handle %p %d blocks: " |
| 430 | "transaction not running\n", handle, nblocks); |
| 431 | goto error_out; |
| 432 | } |
| 433 | |
| 434 | spin_lock(&transaction->t_handle_lock); |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 435 | wanted = atomic_read(&transaction->t_outstanding_credits) + nblocks; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 436 | |
| 437 | if (wanted > journal->j_max_transaction_buffers) { |
| 438 | jbd_debug(3, "denied handle %p %d blocks: " |
| 439 | "transaction too large\n", handle, nblocks); |
| 440 | goto unlock; |
| 441 | } |
| 442 | |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 443 | if (wanted > __jbd2_log_space_left(journal)) { |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 444 | jbd_debug(3, "denied handle %p %d blocks: " |
| 445 | "insufficient log space\n", handle, nblocks); |
| 446 | goto unlock; |
| 447 | } |
| 448 | |
| 449 | handle->h_buffer_credits += nblocks; |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 450 | atomic_add(nblocks, &transaction->t_outstanding_credits); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 451 | result = 0; |
| 452 | |
| 453 | jbd_debug(3, "extended handle %p by %d\n", handle, nblocks); |
| 454 | unlock: |
| 455 | spin_unlock(&transaction->t_handle_lock); |
| 456 | error_out: |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 457 | read_unlock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 458 | out: |
| 459 | return result; |
| 460 | } |
| 461 | |
| 462 | |
| 463 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 464 | * int jbd2_journal_restart() - restart a handle . |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 465 | * @handle: handle to restart |
| 466 | * @nblocks: nr credits requested |
| 467 | * |
| 468 | * Restart a handle for a multi-transaction filesystem |
| 469 | * operation. |
| 470 | * |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 471 | * If the jbd2_journal_extend() call above fails to grant new buffer credits |
| 472 | * to a running handle, a call to jbd2_journal_restart will commit the |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 473 | * handle's transaction so far and reattach the handle to a new |
| 474 | * transaction capabable of guaranteeing the requested number of |
| 475 | * credits. |
| 476 | */ |
Dan Carpenter | d2159fb | 2011-09-04 10:20:14 -0400 | [diff] [blame] | 477 | int jbd2__journal_restart(handle_t *handle, int nblocks, gfp_t gfp_mask) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 478 | { |
| 479 | transaction_t *transaction = handle->h_transaction; |
| 480 | journal_t *journal = transaction->t_journal; |
Theodore Ts'o | e447183 | 2011-02-12 08:18:24 -0500 | [diff] [blame] | 481 | tid_t tid; |
| 482 | int need_to_start, ret; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 483 | |
| 484 | /* If we've had an abort of any type, don't even think about |
| 485 | * actually doing the restart! */ |
| 486 | if (is_handle_aborted(handle)) |
| 487 | return 0; |
| 488 | |
| 489 | /* |
| 490 | * First unlink the handle from its current transaction, and start the |
| 491 | * commit on that. |
| 492 | */ |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 493 | J_ASSERT(atomic_read(&transaction->t_updates) > 0); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 494 | J_ASSERT(journal_current_handle() == handle); |
| 495 | |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 496 | read_lock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 497 | spin_lock(&transaction->t_handle_lock); |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 498 | atomic_sub(handle->h_buffer_credits, |
| 499 | &transaction->t_outstanding_credits); |
| 500 | if (atomic_dec_and_test(&transaction->t_updates)) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 501 | wake_up(&journal->j_wait_updates); |
| 502 | spin_unlock(&transaction->t_handle_lock); |
| 503 | |
| 504 | jbd_debug(2, "restarting handle %p\n", handle); |
Theodore Ts'o | e447183 | 2011-02-12 08:18:24 -0500 | [diff] [blame] | 505 | tid = transaction->t_tid; |
| 506 | need_to_start = !tid_geq(journal->j_commit_request, tid); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 507 | read_unlock(&journal->j_state_lock); |
Theodore Ts'o | e447183 | 2011-02-12 08:18:24 -0500 | [diff] [blame] | 508 | if (need_to_start) |
| 509 | jbd2_log_start_commit(journal, tid); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 510 | |
Jan Kara | 9599b0e | 2009-08-17 21:23:17 -0400 | [diff] [blame] | 511 | lock_map_release(&handle->h_lockdep_map); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 512 | handle->h_buffer_credits = nblocks; |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 513 | ret = start_this_handle(journal, handle, gfp_mask); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 514 | return ret; |
| 515 | } |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 516 | EXPORT_SYMBOL(jbd2__journal_restart); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 517 | |
| 518 | |
Theodore Ts'o | 47def82 | 2010-07-27 11:56:05 -0400 | [diff] [blame] | 519 | int jbd2_journal_restart(handle_t *handle, int nblocks) |
| 520 | { |
| 521 | return jbd2__journal_restart(handle, nblocks, GFP_NOFS); |
| 522 | } |
| 523 | EXPORT_SYMBOL(jbd2_journal_restart); |
| 524 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 525 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 526 | * void jbd2_journal_lock_updates () - establish a transaction barrier. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 527 | * @journal: Journal to establish a barrier on. |
| 528 | * |
| 529 | * This locks out any further updates from being started, and blocks |
| 530 | * until all existing updates have completed, returning only once the |
| 531 | * journal is in a quiescent state with no updates running. |
| 532 | * |
| 533 | * The journal lock should not be held on entry. |
| 534 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 535 | void jbd2_journal_lock_updates(journal_t *journal) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 536 | { |
| 537 | DEFINE_WAIT(wait); |
| 538 | |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 539 | write_lock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 540 | ++journal->j_barrier_count; |
| 541 | |
| 542 | /* Wait until there are no running updates */ |
| 543 | while (1) { |
| 544 | transaction_t *transaction = journal->j_running_transaction; |
| 545 | |
| 546 | if (!transaction) |
| 547 | break; |
| 548 | |
| 549 | spin_lock(&transaction->t_handle_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 550 | prepare_to_wait(&journal->j_wait_updates, &wait, |
| 551 | TASK_UNINTERRUPTIBLE); |
Jan Kara | 9837d8e | 2012-01-04 22:03:11 -0500 | [diff] [blame] | 552 | if (!atomic_read(&transaction->t_updates)) { |
| 553 | spin_unlock(&transaction->t_handle_lock); |
| 554 | finish_wait(&journal->j_wait_updates, &wait); |
| 555 | break; |
| 556 | } |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 557 | spin_unlock(&transaction->t_handle_lock); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 558 | write_unlock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 559 | schedule(); |
| 560 | finish_wait(&journal->j_wait_updates, &wait); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 561 | write_lock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 562 | } |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 563 | write_unlock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 564 | |
| 565 | /* |
| 566 | * We have now established a barrier against other normal updates, but |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 567 | * we also need to barrier against other jbd2_journal_lock_updates() calls |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 568 | * to make sure that we serialise special journal-locked operations |
| 569 | * too. |
| 570 | */ |
| 571 | mutex_lock(&journal->j_barrier); |
| 572 | } |
| 573 | |
| 574 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 575 | * void jbd2_journal_unlock_updates (journal_t* journal) - release barrier |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 576 | * @journal: Journal to release the barrier on. |
| 577 | * |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 578 | * Release a transaction barrier obtained with jbd2_journal_lock_updates(). |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 579 | * |
| 580 | * Should be called without the journal lock held. |
| 581 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 582 | void jbd2_journal_unlock_updates (journal_t *journal) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 583 | { |
| 584 | J_ASSERT(journal->j_barrier_count != 0); |
| 585 | |
| 586 | mutex_unlock(&journal->j_barrier); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 587 | write_lock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 588 | --journal->j_barrier_count; |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 589 | write_unlock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 590 | wake_up(&journal->j_wait_transaction_locked); |
| 591 | } |
| 592 | |
Jan Kara | f91d1d0 | 2009-07-13 16:16:20 -0400 | [diff] [blame] | 593 | static void warn_dirty_buffer(struct buffer_head *bh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 594 | { |
Jan Kara | f91d1d0 | 2009-07-13 16:16:20 -0400 | [diff] [blame] | 595 | char b[BDEVNAME_SIZE]; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 596 | |
Jan Kara | f91d1d0 | 2009-07-13 16:16:20 -0400 | [diff] [blame] | 597 | printk(KERN_WARNING |
Eryu Guan | f2a4452 | 2011-11-01 19:09:18 -0400 | [diff] [blame] | 598 | "JBD2: Spotted dirty metadata buffer (dev = %s, blocknr = %llu). " |
Jan Kara | f91d1d0 | 2009-07-13 16:16:20 -0400 | [diff] [blame] | 599 | "There's a risk of filesystem corruption in case of system " |
| 600 | "crash.\n", |
| 601 | bdevname(bh->b_bdev, b), (unsigned long long)bh->b_blocknr); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 602 | } |
| 603 | |
| 604 | /* |
| 605 | * If the buffer is already part of the current transaction, then there |
| 606 | * is nothing we need to do. If it is already part of a prior |
| 607 | * transaction which we are still committing to disk, then we need to |
| 608 | * make sure that we do not overwrite the old copy: we do copy-out to |
| 609 | * preserve the copy going to disk. We also account the buffer against |
| 610 | * the handle's metadata buffer credits (unless the buffer is already |
| 611 | * part of the transaction, that is). |
| 612 | * |
| 613 | */ |
| 614 | static int |
| 615 | do_get_write_access(handle_t *handle, struct journal_head *jh, |
| 616 | int force_copy) |
| 617 | { |
| 618 | struct buffer_head *bh; |
| 619 | transaction_t *transaction; |
| 620 | journal_t *journal; |
| 621 | int error; |
| 622 | char *frozen_buffer = NULL; |
| 623 | int need_copy = 0; |
| 624 | |
| 625 | if (is_handle_aborted(handle)) |
| 626 | return -EROFS; |
| 627 | |
| 628 | transaction = handle->h_transaction; |
| 629 | journal = transaction->t_journal; |
| 630 | |
Theodore Ts'o | cfef2c6 | 2010-12-18 13:07:34 -0500 | [diff] [blame] | 631 | jbd_debug(5, "journal_head %p, force_copy %d\n", jh, force_copy); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 632 | |
| 633 | JBUFFER_TRACE(jh, "entry"); |
| 634 | repeat: |
| 635 | bh = jh2bh(jh); |
| 636 | |
| 637 | /* @@@ Need to check for errors here at some point. */ |
| 638 | |
| 639 | lock_buffer(bh); |
| 640 | jbd_lock_bh_state(bh); |
| 641 | |
| 642 | /* We now hold the buffer lock so it is safe to query the buffer |
| 643 | * state. Is the buffer dirty? |
| 644 | * |
| 645 | * If so, there are two possibilities. The buffer may be |
| 646 | * non-journaled, and undergoing a quite legitimate writeback. |
| 647 | * Otherwise, it is journaled, and we don't expect dirty buffers |
| 648 | * in that state (the buffers should be marked JBD_Dirty |
| 649 | * instead.) So either the IO is being done under our own |
| 650 | * control and this is a bug, or it's a third party IO such as |
| 651 | * dump(8) (which may leave the buffer scheduled for read --- |
| 652 | * ie. locked but not dirty) or tune2fs (which may actually have |
| 653 | * the buffer dirtied, ugh.) */ |
| 654 | |
| 655 | if (buffer_dirty(bh)) { |
| 656 | /* |
| 657 | * First question: is this buffer already part of the current |
| 658 | * transaction or the existing committing transaction? |
| 659 | */ |
| 660 | if (jh->b_transaction) { |
| 661 | J_ASSERT_JH(jh, |
| 662 | jh->b_transaction == transaction || |
| 663 | jh->b_transaction == |
| 664 | journal->j_committing_transaction); |
| 665 | if (jh->b_next_transaction) |
| 666 | J_ASSERT_JH(jh, jh->b_next_transaction == |
| 667 | transaction); |
Jan Kara | f91d1d0 | 2009-07-13 16:16:20 -0400 | [diff] [blame] | 668 | warn_dirty_buffer(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 669 | } |
| 670 | /* |
| 671 | * In any case we need to clean the dirty flag and we must |
| 672 | * do it under the buffer lock to be sure we don't race |
| 673 | * with running write-out. |
| 674 | */ |
Jan Kara | f91d1d0 | 2009-07-13 16:16:20 -0400 | [diff] [blame] | 675 | JBUFFER_TRACE(jh, "Journalling dirty buffer"); |
| 676 | clear_buffer_dirty(bh); |
| 677 | set_buffer_jbddirty(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 678 | } |
| 679 | |
| 680 | unlock_buffer(bh); |
| 681 | |
| 682 | error = -EROFS; |
| 683 | if (is_handle_aborted(handle)) { |
| 684 | jbd_unlock_bh_state(bh); |
| 685 | goto out; |
| 686 | } |
| 687 | error = 0; |
| 688 | |
| 689 | /* |
| 690 | * The buffer is already part of this transaction if b_transaction or |
| 691 | * b_next_transaction points to it |
| 692 | */ |
| 693 | if (jh->b_transaction == transaction || |
| 694 | jh->b_next_transaction == transaction) |
| 695 | goto done; |
| 696 | |
| 697 | /* |
Josef Bacik | 9fc7c63 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 698 | * this is the first time this transaction is touching this buffer, |
| 699 | * reset the modified flag |
| 700 | */ |
| 701 | jh->b_modified = 0; |
| 702 | |
| 703 | /* |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 704 | * If there is already a copy-out version of this buffer, then we don't |
| 705 | * need to make another one |
| 706 | */ |
| 707 | if (jh->b_frozen_data) { |
| 708 | JBUFFER_TRACE(jh, "has frozen data"); |
| 709 | J_ASSERT_JH(jh, jh->b_next_transaction == NULL); |
| 710 | jh->b_next_transaction = transaction; |
| 711 | goto done; |
| 712 | } |
| 713 | |
| 714 | /* Is there data here we need to preserve? */ |
| 715 | |
| 716 | if (jh->b_transaction && jh->b_transaction != transaction) { |
| 717 | JBUFFER_TRACE(jh, "owned by older transaction"); |
| 718 | J_ASSERT_JH(jh, jh->b_next_transaction == NULL); |
| 719 | J_ASSERT_JH(jh, jh->b_transaction == |
| 720 | journal->j_committing_transaction); |
| 721 | |
| 722 | /* There is one case we have to be very careful about. |
| 723 | * If the committing transaction is currently writing |
| 724 | * this buffer out to disk and has NOT made a copy-out, |
| 725 | * then we cannot modify the buffer contents at all |
| 726 | * right now. The essence of copy-out is that it is the |
| 727 | * extra copy, not the primary copy, which gets |
| 728 | * journaled. If the primary copy is already going to |
| 729 | * disk then we cannot do copy-out here. */ |
| 730 | |
| 731 | if (jh->b_jlist == BJ_Shadow) { |
| 732 | DEFINE_WAIT_BIT(wait, &bh->b_state, BH_Unshadow); |
| 733 | wait_queue_head_t *wqh; |
| 734 | |
| 735 | wqh = bit_waitqueue(&bh->b_state, BH_Unshadow); |
| 736 | |
| 737 | JBUFFER_TRACE(jh, "on shadow: sleep"); |
| 738 | jbd_unlock_bh_state(bh); |
| 739 | /* commit wakes up all shadow buffers after IO */ |
| 740 | for ( ; ; ) { |
| 741 | prepare_to_wait(wqh, &wait.wait, |
| 742 | TASK_UNINTERRUPTIBLE); |
| 743 | if (jh->b_jlist != BJ_Shadow) |
| 744 | break; |
| 745 | schedule(); |
| 746 | } |
| 747 | finish_wait(wqh, &wait.wait); |
| 748 | goto repeat; |
| 749 | } |
| 750 | |
| 751 | /* Only do the copy if the currently-owning transaction |
| 752 | * still needs it. If it is on the Forget list, the |
| 753 | * committing transaction is past that stage. The |
| 754 | * buffer had better remain locked during the kmalloc, |
| 755 | * but that should be true --- we hold the journal lock |
| 756 | * still and the buffer is already on the BUF_JOURNAL |
| 757 | * list so won't be flushed. |
| 758 | * |
| 759 | * Subtle point, though: if this is a get_undo_access, |
| 760 | * then we will be relying on the frozen_data to contain |
| 761 | * the new value of the committed_data record after the |
| 762 | * transaction, so we HAVE to force the frozen_data copy |
| 763 | * in that case. */ |
| 764 | |
| 765 | if (jh->b_jlist != BJ_Forget || force_copy) { |
| 766 | JBUFFER_TRACE(jh, "generate frozen data"); |
| 767 | if (!frozen_buffer) { |
| 768 | JBUFFER_TRACE(jh, "allocate memory for buffer"); |
| 769 | jbd_unlock_bh_state(bh); |
| 770 | frozen_buffer = |
Mingming Cao | af1e76d | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 771 | jbd2_alloc(jh2bh(jh)->b_size, |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 772 | GFP_NOFS); |
| 773 | if (!frozen_buffer) { |
| 774 | printk(KERN_EMERG |
| 775 | "%s: OOM for frozen_buffer\n", |
Harvey Harrison | 329d291 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 776 | __func__); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 777 | JBUFFER_TRACE(jh, "oom!"); |
| 778 | error = -ENOMEM; |
| 779 | jbd_lock_bh_state(bh); |
| 780 | goto done; |
| 781 | } |
| 782 | goto repeat; |
| 783 | } |
| 784 | jh->b_frozen_data = frozen_buffer; |
| 785 | frozen_buffer = NULL; |
| 786 | need_copy = 1; |
| 787 | } |
| 788 | jh->b_next_transaction = transaction; |
| 789 | } |
| 790 | |
| 791 | |
| 792 | /* |
| 793 | * Finally, if the buffer is not journaled right now, we need to make |
| 794 | * sure it doesn't get written to disk before the caller actually |
| 795 | * commits the new data |
| 796 | */ |
| 797 | if (!jh->b_transaction) { |
| 798 | JBUFFER_TRACE(jh, "no transaction"); |
| 799 | J_ASSERT_JH(jh, !jh->b_next_transaction); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 800 | JBUFFER_TRACE(jh, "file as BJ_Reserved"); |
| 801 | spin_lock(&journal->j_list_lock); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 802 | __jbd2_journal_file_buffer(jh, transaction, BJ_Reserved); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 803 | spin_unlock(&journal->j_list_lock); |
| 804 | } |
| 805 | |
| 806 | done: |
| 807 | if (need_copy) { |
| 808 | struct page *page; |
| 809 | int offset; |
| 810 | char *source; |
| 811 | |
| 812 | J_EXPECT_JH(jh, buffer_uptodate(jh2bh(jh)), |
| 813 | "Possible IO failure.\n"); |
| 814 | page = jh2bh(jh)->b_page; |
Theodore Ts'o | a1dd533 | 2010-12-18 13:13:40 -0500 | [diff] [blame] | 815 | offset = offset_in_page(jh2bh(jh)->b_data); |
Cong Wang | 303a8f2 | 2011-11-25 23:14:31 +0800 | [diff] [blame] | 816 | source = kmap_atomic(page); |
Jan Kara | 13ceef0 | 2010-07-14 07:56:33 +0200 | [diff] [blame] | 817 | /* Fire data frozen trigger just before we copy the data */ |
| 818 | jbd2_buffer_frozen_trigger(jh, source + offset, |
| 819 | jh->b_triggers); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 820 | memcpy(jh->b_frozen_data, source+offset, jh2bh(jh)->b_size); |
Cong Wang | 303a8f2 | 2011-11-25 23:14:31 +0800 | [diff] [blame] | 821 | kunmap_atomic(source); |
Joel Becker | e06c822 | 2008-09-11 15:35:47 -0700 | [diff] [blame] | 822 | |
| 823 | /* |
| 824 | * Now that the frozen data is saved off, we need to store |
| 825 | * any matching triggers. |
| 826 | */ |
| 827 | jh->b_frozen_triggers = jh->b_triggers; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 828 | } |
| 829 | jbd_unlock_bh_state(bh); |
| 830 | |
| 831 | /* |
| 832 | * If we are about to journal a buffer, then any revoke pending on it is |
| 833 | * no longer valid |
| 834 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 835 | jbd2_journal_cancel_revoke(handle, jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 836 | |
| 837 | out: |
| 838 | if (unlikely(frozen_buffer)) /* It's usually NULL */ |
Mingming Cao | af1e76d | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 839 | jbd2_free(frozen_buffer, bh->b_size); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 840 | |
| 841 | JBUFFER_TRACE(jh, "exit"); |
| 842 | return error; |
| 843 | } |
| 844 | |
| 845 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 846 | * int jbd2_journal_get_write_access() - notify intent to modify a buffer for metadata (not data) update. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 847 | * @handle: transaction to add buffer modifications to |
| 848 | * @bh: bh to be used for metadata writes |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 849 | * |
| 850 | * Returns an error code or 0 on success. |
| 851 | * |
| 852 | * In full data journalling mode the buffer may be of type BJ_AsyncData, |
| 853 | * because we're write()ing a buffer which is also part of a shared mapping. |
| 854 | */ |
| 855 | |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 856 | int jbd2_journal_get_write_access(handle_t *handle, struct buffer_head *bh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 857 | { |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 858 | struct journal_head *jh = jbd2_journal_add_journal_head(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 859 | int rc; |
| 860 | |
| 861 | /* We do not want to get caught playing with fields which the |
| 862 | * log thread also manipulates. Make sure that the buffer |
| 863 | * completes any outstanding IO before proceeding. */ |
| 864 | rc = do_get_write_access(handle, jh, 0); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 865 | jbd2_journal_put_journal_head(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 866 | return rc; |
| 867 | } |
| 868 | |
| 869 | |
| 870 | /* |
| 871 | * When the user wants to journal a newly created buffer_head |
| 872 | * (ie. getblk() returned a new buffer and we are going to populate it |
| 873 | * manually rather than reading off disk), then we need to keep the |
| 874 | * buffer_head locked until it has been completely filled with new |
| 875 | * data. In this case, we should be able to make the assertion that |
| 876 | * the bh is not already part of an existing transaction. |
| 877 | * |
| 878 | * The buffer should already be locked by the caller by this point. |
| 879 | * There is no lock ranking violation: it was a newly created, |
| 880 | * unlocked buffer beforehand. */ |
| 881 | |
| 882 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 883 | * int jbd2_journal_get_create_access () - notify intent to use newly created bh |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 884 | * @handle: transaction to new buffer to |
| 885 | * @bh: new buffer. |
| 886 | * |
| 887 | * Call this if you create a new bh. |
| 888 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 889 | int jbd2_journal_get_create_access(handle_t *handle, struct buffer_head *bh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 890 | { |
| 891 | transaction_t *transaction = handle->h_transaction; |
| 892 | journal_t *journal = transaction->t_journal; |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 893 | struct journal_head *jh = jbd2_journal_add_journal_head(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 894 | int err; |
| 895 | |
| 896 | jbd_debug(5, "journal_head %p\n", jh); |
| 897 | err = -EROFS; |
| 898 | if (is_handle_aborted(handle)) |
| 899 | goto out; |
| 900 | err = 0; |
| 901 | |
| 902 | JBUFFER_TRACE(jh, "entry"); |
| 903 | /* |
| 904 | * The buffer may already belong to this transaction due to pre-zeroing |
| 905 | * in the filesystem's new_block code. It may also be on the previous, |
| 906 | * committing transaction's lists, but it HAS to be in Forget state in |
| 907 | * that case: the transaction must have deleted the buffer for it to be |
| 908 | * reused here. |
| 909 | */ |
| 910 | jbd_lock_bh_state(bh); |
| 911 | spin_lock(&journal->j_list_lock); |
| 912 | J_ASSERT_JH(jh, (jh->b_transaction == transaction || |
| 913 | jh->b_transaction == NULL || |
| 914 | (jh->b_transaction == journal->j_committing_transaction && |
| 915 | jh->b_jlist == BJ_Forget))); |
| 916 | |
| 917 | J_ASSERT_JH(jh, jh->b_next_transaction == NULL); |
| 918 | J_ASSERT_JH(jh, buffer_locked(jh2bh(jh))); |
| 919 | |
| 920 | if (jh->b_transaction == NULL) { |
Jan Kara | f91d1d0 | 2009-07-13 16:16:20 -0400 | [diff] [blame] | 921 | /* |
| 922 | * Previous jbd2_journal_forget() could have left the buffer |
| 923 | * with jbddirty bit set because it was being committed. When |
| 924 | * the commit finished, we've filed the buffer for |
| 925 | * checkpointing and marked it dirty. Now we are reallocating |
| 926 | * the buffer so the transaction freeing it must have |
| 927 | * committed and so it's safe to clear the dirty bit. |
| 928 | */ |
| 929 | clear_buffer_dirty(jh2bh(jh)); |
Josef Bacik | 9fc7c63 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 930 | /* first access by this transaction */ |
| 931 | jh->b_modified = 0; |
| 932 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 933 | JBUFFER_TRACE(jh, "file as BJ_Reserved"); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 934 | __jbd2_journal_file_buffer(jh, transaction, BJ_Reserved); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 935 | } else if (jh->b_transaction == journal->j_committing_transaction) { |
Josef Bacik | 9fc7c63 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 936 | /* first access by this transaction */ |
| 937 | jh->b_modified = 0; |
| 938 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 939 | JBUFFER_TRACE(jh, "set next transaction"); |
| 940 | jh->b_next_transaction = transaction; |
| 941 | } |
| 942 | spin_unlock(&journal->j_list_lock); |
| 943 | jbd_unlock_bh_state(bh); |
| 944 | |
| 945 | /* |
| 946 | * akpm: I added this. ext3_alloc_branch can pick up new indirect |
| 947 | * blocks which contain freed but then revoked metadata. We need |
| 948 | * to cancel the revoke in case we end up freeing it yet again |
| 949 | * and the reallocating as data - this would cause a second revoke, |
| 950 | * which hits an assertion error. |
| 951 | */ |
| 952 | JBUFFER_TRACE(jh, "cancelling revoke"); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 953 | jbd2_journal_cancel_revoke(handle, jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 954 | out: |
Ding Dinghua | 3991b40 | 2011-05-25 17:43:48 -0400 | [diff] [blame] | 955 | jbd2_journal_put_journal_head(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 956 | return err; |
| 957 | } |
| 958 | |
| 959 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 960 | * int jbd2_journal_get_undo_access() - Notify intent to modify metadata with |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 961 | * non-rewindable consequences |
| 962 | * @handle: transaction |
| 963 | * @bh: buffer to undo |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 964 | * |
| 965 | * Sometimes there is a need to distinguish between metadata which has |
| 966 | * been committed to disk and that which has not. The ext3fs code uses |
| 967 | * this for freeing and allocating space, we have to make sure that we |
| 968 | * do not reuse freed space until the deallocation has been committed, |
| 969 | * since if we overwrote that space we would make the delete |
| 970 | * un-rewindable in case of a crash. |
| 971 | * |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 972 | * To deal with that, jbd2_journal_get_undo_access requests write access to a |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 973 | * buffer for parts of non-rewindable operations such as delete |
| 974 | * operations on the bitmaps. The journaling code must keep a copy of |
| 975 | * the buffer's contents prior to the undo_access call until such time |
| 976 | * as we know that the buffer has definitely been committed to disk. |
| 977 | * |
| 978 | * We never need to know which transaction the committed data is part |
| 979 | * of, buffers touched here are guaranteed to be dirtied later and so |
| 980 | * will be committed to a new transaction in due course, at which point |
| 981 | * we can discard the old committed data pointer. |
| 982 | * |
| 983 | * Returns error number or 0 on success. |
| 984 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 985 | int jbd2_journal_get_undo_access(handle_t *handle, struct buffer_head *bh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 986 | { |
| 987 | int err; |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 988 | struct journal_head *jh = jbd2_journal_add_journal_head(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 989 | char *committed_data = NULL; |
| 990 | |
| 991 | JBUFFER_TRACE(jh, "entry"); |
| 992 | |
| 993 | /* |
| 994 | * Do this first --- it can drop the journal lock, so we want to |
| 995 | * make sure that obtaining the committed_data is done |
| 996 | * atomically wrt. completion of any outstanding commits. |
| 997 | */ |
| 998 | err = do_get_write_access(handle, jh, 1); |
| 999 | if (err) |
| 1000 | goto out; |
| 1001 | |
| 1002 | repeat: |
| 1003 | if (!jh->b_committed_data) { |
Mingming Cao | af1e76d | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 1004 | committed_data = jbd2_alloc(jh2bh(jh)->b_size, GFP_NOFS); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1005 | if (!committed_data) { |
| 1006 | printk(KERN_EMERG "%s: No memory for committed data\n", |
Harvey Harrison | 329d291 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 1007 | __func__); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1008 | err = -ENOMEM; |
| 1009 | goto out; |
| 1010 | } |
| 1011 | } |
| 1012 | |
| 1013 | jbd_lock_bh_state(bh); |
| 1014 | if (!jh->b_committed_data) { |
| 1015 | /* Copy out the current buffer contents into the |
| 1016 | * preserved, committed copy. */ |
| 1017 | JBUFFER_TRACE(jh, "generate b_committed data"); |
| 1018 | if (!committed_data) { |
| 1019 | jbd_unlock_bh_state(bh); |
| 1020 | goto repeat; |
| 1021 | } |
| 1022 | |
| 1023 | jh->b_committed_data = committed_data; |
| 1024 | committed_data = NULL; |
| 1025 | memcpy(jh->b_committed_data, bh->b_data, bh->b_size); |
| 1026 | } |
| 1027 | jbd_unlock_bh_state(bh); |
| 1028 | out: |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1029 | jbd2_journal_put_journal_head(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1030 | if (unlikely(committed_data)) |
Mingming Cao | af1e76d | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 1031 | jbd2_free(committed_data, bh->b_size); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1032 | return err; |
| 1033 | } |
| 1034 | |
| 1035 | /** |
Joel Becker | e06c822 | 2008-09-11 15:35:47 -0700 | [diff] [blame] | 1036 | * void jbd2_journal_set_triggers() - Add triggers for commit writeout |
| 1037 | * @bh: buffer to trigger on |
| 1038 | * @type: struct jbd2_buffer_trigger_type containing the trigger(s). |
| 1039 | * |
| 1040 | * Set any triggers on this journal_head. This is always safe, because |
| 1041 | * triggers for a committing buffer will be saved off, and triggers for |
| 1042 | * a running transaction will match the buffer in that transaction. |
| 1043 | * |
| 1044 | * Call with NULL to clear the triggers. |
| 1045 | */ |
| 1046 | void jbd2_journal_set_triggers(struct buffer_head *bh, |
| 1047 | struct jbd2_buffer_trigger_type *type) |
| 1048 | { |
| 1049 | struct journal_head *jh = bh2jh(bh); |
| 1050 | |
| 1051 | jh->b_triggers = type; |
| 1052 | } |
| 1053 | |
Jan Kara | 13ceef0 | 2010-07-14 07:56:33 +0200 | [diff] [blame] | 1054 | void jbd2_buffer_frozen_trigger(struct journal_head *jh, void *mapped_data, |
Joel Becker | e06c822 | 2008-09-11 15:35:47 -0700 | [diff] [blame] | 1055 | struct jbd2_buffer_trigger_type *triggers) |
| 1056 | { |
| 1057 | struct buffer_head *bh = jh2bh(jh); |
| 1058 | |
Jan Kara | 13ceef0 | 2010-07-14 07:56:33 +0200 | [diff] [blame] | 1059 | if (!triggers || !triggers->t_frozen) |
Joel Becker | e06c822 | 2008-09-11 15:35:47 -0700 | [diff] [blame] | 1060 | return; |
| 1061 | |
Jan Kara | 13ceef0 | 2010-07-14 07:56:33 +0200 | [diff] [blame] | 1062 | triggers->t_frozen(triggers, bh, mapped_data, bh->b_size); |
Joel Becker | e06c822 | 2008-09-11 15:35:47 -0700 | [diff] [blame] | 1063 | } |
| 1064 | |
| 1065 | void jbd2_buffer_abort_trigger(struct journal_head *jh, |
| 1066 | struct jbd2_buffer_trigger_type *triggers) |
| 1067 | { |
| 1068 | if (!triggers || !triggers->t_abort) |
| 1069 | return; |
| 1070 | |
| 1071 | triggers->t_abort(triggers, jh2bh(jh)); |
| 1072 | } |
| 1073 | |
| 1074 | |
| 1075 | |
| 1076 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1077 | * int jbd2_journal_dirty_metadata() - mark a buffer as containing dirty metadata |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1078 | * @handle: transaction to add buffer to. |
| 1079 | * @bh: buffer to mark |
| 1080 | * |
| 1081 | * mark dirty metadata which needs to be journaled as part of the current |
| 1082 | * transaction. |
| 1083 | * |
Theodore Ts'o | 9ea7a0d | 2011-09-04 10:18:14 -0400 | [diff] [blame] | 1084 | * The buffer must have previously had jbd2_journal_get_write_access() |
| 1085 | * called so that it has a valid journal_head attached to the buffer |
| 1086 | * head. |
| 1087 | * |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1088 | * The buffer is placed on the transaction's metadata list and is marked |
| 1089 | * as belonging to the transaction. |
| 1090 | * |
| 1091 | * Returns error number or 0 on success. |
| 1092 | * |
| 1093 | * Special care needs to be taken if the buffer already belongs to the |
| 1094 | * current committing transaction (in which case we should have frozen |
| 1095 | * data present for that commit). In that case, we don't relink the |
| 1096 | * buffer: that only gets done when the old transaction finally |
| 1097 | * completes its commit. |
| 1098 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1099 | int jbd2_journal_dirty_metadata(handle_t *handle, struct buffer_head *bh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1100 | { |
| 1101 | transaction_t *transaction = handle->h_transaction; |
| 1102 | journal_t *journal = transaction->t_journal; |
| 1103 | struct journal_head *jh = bh2jh(bh); |
Theodore Ts'o | 9ea7a0d | 2011-09-04 10:18:14 -0400 | [diff] [blame] | 1104 | int ret = 0; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1105 | |
| 1106 | jbd_debug(5, "journal_head %p\n", jh); |
| 1107 | JBUFFER_TRACE(jh, "entry"); |
| 1108 | if (is_handle_aborted(handle)) |
| 1109 | goto out; |
Theodore Ts'o | 9ea7a0d | 2011-09-04 10:18:14 -0400 | [diff] [blame] | 1110 | if (!buffer_jbd(bh)) { |
| 1111 | ret = -EUCLEAN; |
| 1112 | goto out; |
| 1113 | } |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1114 | |
| 1115 | jbd_lock_bh_state(bh); |
| 1116 | |
| 1117 | if (jh->b_modified == 0) { |
| 1118 | /* |
| 1119 | * This buffer's got modified and becoming part |
| 1120 | * of the transaction. This needs to be done |
| 1121 | * once a transaction -bzzz |
| 1122 | */ |
| 1123 | jh->b_modified = 1; |
| 1124 | J_ASSERT_JH(jh, handle->h_buffer_credits > 0); |
| 1125 | handle->h_buffer_credits--; |
| 1126 | } |
| 1127 | |
| 1128 | /* |
| 1129 | * fastpath, to avoid expensive locking. If this buffer is already |
| 1130 | * on the running transaction's metadata list there is nothing to do. |
| 1131 | * Nobody can take it off again because there is a handle open. |
| 1132 | * I _think_ we're OK here with SMP barriers - a mistaken decision will |
| 1133 | * result in this test being false, so we go in and take the locks. |
| 1134 | */ |
| 1135 | if (jh->b_transaction == transaction && jh->b_jlist == BJ_Metadata) { |
| 1136 | JBUFFER_TRACE(jh, "fastpath"); |
Theodore Ts'o | 9ea7a0d | 2011-09-04 10:18:14 -0400 | [diff] [blame] | 1137 | if (unlikely(jh->b_transaction != |
| 1138 | journal->j_running_transaction)) { |
| 1139 | printk(KERN_EMERG "JBD: %s: " |
| 1140 | "jh->b_transaction (%llu, %p, %u) != " |
| 1141 | "journal->j_running_transaction (%p, %u)", |
| 1142 | journal->j_devname, |
| 1143 | (unsigned long long) bh->b_blocknr, |
| 1144 | jh->b_transaction, |
| 1145 | jh->b_transaction ? jh->b_transaction->t_tid : 0, |
| 1146 | journal->j_running_transaction, |
| 1147 | journal->j_running_transaction ? |
| 1148 | journal->j_running_transaction->t_tid : 0); |
| 1149 | ret = -EINVAL; |
| 1150 | } |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1151 | goto out_unlock_bh; |
| 1152 | } |
| 1153 | |
| 1154 | set_buffer_jbddirty(bh); |
| 1155 | |
| 1156 | /* |
| 1157 | * Metadata already on the current transaction list doesn't |
| 1158 | * need to be filed. Metadata on another transaction's list must |
| 1159 | * be committing, and will be refiled once the commit completes: |
| 1160 | * leave it alone for now. |
| 1161 | */ |
| 1162 | if (jh->b_transaction != transaction) { |
| 1163 | JBUFFER_TRACE(jh, "already on other transaction"); |
Theodore Ts'o | 9ea7a0d | 2011-09-04 10:18:14 -0400 | [diff] [blame] | 1164 | if (unlikely(jh->b_transaction != |
| 1165 | journal->j_committing_transaction)) { |
| 1166 | printk(KERN_EMERG "JBD: %s: " |
| 1167 | "jh->b_transaction (%llu, %p, %u) != " |
| 1168 | "journal->j_committing_transaction (%p, %u)", |
| 1169 | journal->j_devname, |
| 1170 | (unsigned long long) bh->b_blocknr, |
| 1171 | jh->b_transaction, |
| 1172 | jh->b_transaction ? jh->b_transaction->t_tid : 0, |
| 1173 | journal->j_committing_transaction, |
| 1174 | journal->j_committing_transaction ? |
| 1175 | journal->j_committing_transaction->t_tid : 0); |
| 1176 | ret = -EINVAL; |
| 1177 | } |
| 1178 | if (unlikely(jh->b_next_transaction != transaction)) { |
| 1179 | printk(KERN_EMERG "JBD: %s: " |
| 1180 | "jh->b_next_transaction (%llu, %p, %u) != " |
| 1181 | "transaction (%p, %u)", |
| 1182 | journal->j_devname, |
| 1183 | (unsigned long long) bh->b_blocknr, |
| 1184 | jh->b_next_transaction, |
| 1185 | jh->b_next_transaction ? |
| 1186 | jh->b_next_transaction->t_tid : 0, |
| 1187 | transaction, transaction->t_tid); |
| 1188 | ret = -EINVAL; |
| 1189 | } |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1190 | /* And this case is illegal: we can't reuse another |
| 1191 | * transaction's data buffer, ever. */ |
| 1192 | goto out_unlock_bh; |
| 1193 | } |
| 1194 | |
| 1195 | /* That test should have eliminated the following case: */ |
Mingming Cao | 4019191 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 1196 | J_ASSERT_JH(jh, jh->b_frozen_data == NULL); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1197 | |
| 1198 | JBUFFER_TRACE(jh, "file as BJ_Metadata"); |
| 1199 | spin_lock(&journal->j_list_lock); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1200 | __jbd2_journal_file_buffer(jh, handle->h_transaction, BJ_Metadata); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1201 | spin_unlock(&journal->j_list_lock); |
| 1202 | out_unlock_bh: |
| 1203 | jbd_unlock_bh_state(bh); |
| 1204 | out: |
| 1205 | JBUFFER_TRACE(jh, "exit"); |
Randy Dunlap | 4470575 | 2011-10-27 04:05:13 -0400 | [diff] [blame] | 1206 | WARN_ON(ret); /* All errors are bugs, so dump the stack */ |
Theodore Ts'o | 9ea7a0d | 2011-09-04 10:18:14 -0400 | [diff] [blame] | 1207 | return ret; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1208 | } |
| 1209 | |
| 1210 | /* |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1211 | * jbd2_journal_release_buffer: undo a get_write_access without any buffer |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1212 | * updates, if the update decided in the end that it didn't need access. |
| 1213 | * |
| 1214 | */ |
| 1215 | void |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1216 | jbd2_journal_release_buffer(handle_t *handle, struct buffer_head *bh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1217 | { |
| 1218 | BUFFER_TRACE(bh, "entry"); |
| 1219 | } |
| 1220 | |
| 1221 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1222 | * void jbd2_journal_forget() - bforget() for potentially-journaled buffers. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1223 | * @handle: transaction handle |
| 1224 | * @bh: bh to 'forget' |
| 1225 | * |
| 1226 | * We can only do the bforget if there are no commits pending against the |
| 1227 | * buffer. If the buffer is dirty in the current running transaction we |
| 1228 | * can safely unlink it. |
| 1229 | * |
| 1230 | * bh may not be a journalled buffer at all - it may be a non-JBD |
| 1231 | * buffer which came off the hashtable. Check for this. |
| 1232 | * |
| 1233 | * Decrements bh->b_count by one. |
| 1234 | * |
| 1235 | * Allow this call even if the handle has aborted --- it may be part of |
| 1236 | * the caller's cleanup after an abort. |
| 1237 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1238 | int jbd2_journal_forget (handle_t *handle, struct buffer_head *bh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1239 | { |
| 1240 | transaction_t *transaction = handle->h_transaction; |
| 1241 | journal_t *journal = transaction->t_journal; |
| 1242 | struct journal_head *jh; |
| 1243 | int drop_reserve = 0; |
| 1244 | int err = 0; |
Josef Bacik | 1dfc322 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 1245 | int was_modified = 0; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1246 | |
| 1247 | BUFFER_TRACE(bh, "entry"); |
| 1248 | |
| 1249 | jbd_lock_bh_state(bh); |
| 1250 | spin_lock(&journal->j_list_lock); |
| 1251 | |
| 1252 | if (!buffer_jbd(bh)) |
| 1253 | goto not_jbd; |
| 1254 | jh = bh2jh(bh); |
| 1255 | |
| 1256 | /* Critical error: attempting to delete a bitmap buffer, maybe? |
| 1257 | * Don't do any jbd operations, and return an error. */ |
| 1258 | if (!J_EXPECT_JH(jh, !jh->b_committed_data, |
| 1259 | "inconsistent data on disk")) { |
| 1260 | err = -EIO; |
| 1261 | goto not_jbd; |
| 1262 | } |
| 1263 | |
Josef Bacik | 1dfc322 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 1264 | /* keep track of wether or not this transaction modified us */ |
| 1265 | was_modified = jh->b_modified; |
| 1266 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1267 | /* |
| 1268 | * The buffer's going from the transaction, we must drop |
| 1269 | * all references -bzzz |
| 1270 | */ |
| 1271 | jh->b_modified = 0; |
| 1272 | |
| 1273 | if (jh->b_transaction == handle->h_transaction) { |
| 1274 | J_ASSERT_JH(jh, !jh->b_frozen_data); |
| 1275 | |
| 1276 | /* If we are forgetting a buffer which is already part |
| 1277 | * of this transaction, then we can just drop it from |
| 1278 | * the transaction immediately. */ |
| 1279 | clear_buffer_dirty(bh); |
| 1280 | clear_buffer_jbddirty(bh); |
| 1281 | |
| 1282 | JBUFFER_TRACE(jh, "belongs to current transaction: unfile"); |
| 1283 | |
Josef Bacik | 1dfc322 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 1284 | /* |
| 1285 | * we only want to drop a reference if this transaction |
| 1286 | * modified the buffer |
| 1287 | */ |
| 1288 | if (was_modified) |
| 1289 | drop_reserve = 1; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1290 | |
| 1291 | /* |
| 1292 | * We are no longer going to journal this buffer. |
| 1293 | * However, the commit of this transaction is still |
| 1294 | * important to the buffer: the delete that we are now |
| 1295 | * processing might obsolete an old log entry, so by |
| 1296 | * committing, we can satisfy the buffer's checkpoint. |
| 1297 | * |
| 1298 | * So, if we have a checkpoint on the buffer, we should |
| 1299 | * now refile the buffer on our BJ_Forget list so that |
| 1300 | * we know to remove the checkpoint after we commit. |
| 1301 | */ |
| 1302 | |
| 1303 | if (jh->b_cp_transaction) { |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1304 | __jbd2_journal_temp_unlink_buffer(jh); |
| 1305 | __jbd2_journal_file_buffer(jh, transaction, BJ_Forget); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1306 | } else { |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1307 | __jbd2_journal_unfile_buffer(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1308 | if (!buffer_jbd(bh)) { |
| 1309 | spin_unlock(&journal->j_list_lock); |
| 1310 | jbd_unlock_bh_state(bh); |
| 1311 | __bforget(bh); |
| 1312 | goto drop; |
| 1313 | } |
| 1314 | } |
| 1315 | } else if (jh->b_transaction) { |
| 1316 | J_ASSERT_JH(jh, (jh->b_transaction == |
| 1317 | journal->j_committing_transaction)); |
| 1318 | /* However, if the buffer is still owned by a prior |
| 1319 | * (committing) transaction, we can't drop it yet... */ |
| 1320 | JBUFFER_TRACE(jh, "belongs to older transaction"); |
| 1321 | /* ... but we CAN drop it from the new transaction if we |
| 1322 | * have also modified it since the original commit. */ |
| 1323 | |
| 1324 | if (jh->b_next_transaction) { |
| 1325 | J_ASSERT(jh->b_next_transaction == transaction); |
| 1326 | jh->b_next_transaction = NULL; |
Josef Bacik | 1dfc322 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 1327 | |
| 1328 | /* |
| 1329 | * only drop a reference if this transaction modified |
| 1330 | * the buffer |
| 1331 | */ |
| 1332 | if (was_modified) |
| 1333 | drop_reserve = 1; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1334 | } |
| 1335 | } |
| 1336 | |
| 1337 | not_jbd: |
| 1338 | spin_unlock(&journal->j_list_lock); |
| 1339 | jbd_unlock_bh_state(bh); |
| 1340 | __brelse(bh); |
| 1341 | drop: |
| 1342 | if (drop_reserve) { |
| 1343 | /* no need to reserve log space for this block -bzzz */ |
| 1344 | handle->h_buffer_credits++; |
| 1345 | } |
| 1346 | return err; |
| 1347 | } |
| 1348 | |
| 1349 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1350 | * int jbd2_journal_stop() - complete a transaction |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1351 | * @handle: tranaction to complete. |
| 1352 | * |
| 1353 | * All done for a particular handle. |
| 1354 | * |
| 1355 | * There is not much action needed here. We just return any remaining |
| 1356 | * buffer credits to the transaction and remove the handle. The only |
| 1357 | * complication is that we need to start a commit operation if the |
| 1358 | * filesystem is marked for synchronous update. |
| 1359 | * |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1360 | * jbd2_journal_stop itself will not usually return an error, but it may |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1361 | * do so in unusual circumstances. In particular, expect it to |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1362 | * return -EIO if a jbd2_journal_abort has been executed since the |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1363 | * transaction began. |
| 1364 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1365 | int jbd2_journal_stop(handle_t *handle) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1366 | { |
| 1367 | transaction_t *transaction = handle->h_transaction; |
| 1368 | journal_t *journal = transaction->t_journal; |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 1369 | int err, wait_for_commit = 0; |
| 1370 | tid_t tid; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1371 | pid_t pid; |
| 1372 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1373 | J_ASSERT(journal_current_handle() == handle); |
| 1374 | |
| 1375 | if (is_handle_aborted(handle)) |
| 1376 | err = -EIO; |
OGAWA Hirofumi | 3e2a532 | 2006-10-19 23:29:11 -0700 | [diff] [blame] | 1377 | else { |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 1378 | J_ASSERT(atomic_read(&transaction->t_updates) > 0); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1379 | err = 0; |
OGAWA Hirofumi | 3e2a532 | 2006-10-19 23:29:11 -0700 | [diff] [blame] | 1380 | } |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1381 | |
| 1382 | if (--handle->h_ref > 0) { |
| 1383 | jbd_debug(4, "h_ref %d -> %d\n", handle->h_ref + 1, |
| 1384 | handle->h_ref); |
| 1385 | return err; |
| 1386 | } |
| 1387 | |
| 1388 | jbd_debug(4, "Handle %p going down\n", handle); |
| 1389 | |
| 1390 | /* |
| 1391 | * Implement synchronous transaction batching. If the handle |
| 1392 | * was synchronous, don't force a commit immediately. Let's |
Josef Bacik | e07f718 | 2008-11-26 01:14:26 -0500 | [diff] [blame] | 1393 | * yield and let another thread piggyback onto this |
| 1394 | * transaction. Keep doing that while new threads continue to |
| 1395 | * arrive. It doesn't cost much - we're about to run a commit |
| 1396 | * and sleep on IO anyway. Speeds up many-threaded, many-dir |
| 1397 | * operations by 30x or more... |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1398 | * |
Josef Bacik | e07f718 | 2008-11-26 01:14:26 -0500 | [diff] [blame] | 1399 | * We try and optimize the sleep time against what the |
| 1400 | * underlying disk can do, instead of having a static sleep |
| 1401 | * time. This is useful for the case where our storage is so |
| 1402 | * fast that it is more optimal to go ahead and force a flush |
| 1403 | * and wait for the transaction to be committed than it is to |
| 1404 | * wait for an arbitrary amount of time for new writers to |
| 1405 | * join the transaction. We achieve this by measuring how |
| 1406 | * long it takes to commit a transaction, and compare it with |
| 1407 | * how long this transaction has been running, and if run time |
| 1408 | * < commit time then we sleep for the delta and commit. This |
| 1409 | * greatly helps super fast disks that would see slowdowns as |
| 1410 | * more threads started doing fsyncs. |
| 1411 | * |
| 1412 | * But don't do this if this process was the most recent one |
| 1413 | * to perform a synchronous write. We do this to detect the |
| 1414 | * case where a single process is doing a stream of sync |
| 1415 | * writes. No point in waiting for joiners in that case. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1416 | */ |
| 1417 | pid = current->pid; |
| 1418 | if (handle->h_sync && journal->j_last_sync_writer != pid) { |
Josef Bacik | e07f718 | 2008-11-26 01:14:26 -0500 | [diff] [blame] | 1419 | u64 commit_time, trans_time; |
| 1420 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1421 | journal->j_last_sync_writer = pid; |
Josef Bacik | e07f718 | 2008-11-26 01:14:26 -0500 | [diff] [blame] | 1422 | |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 1423 | read_lock(&journal->j_state_lock); |
Josef Bacik | e07f718 | 2008-11-26 01:14:26 -0500 | [diff] [blame] | 1424 | commit_time = journal->j_average_commit_time; |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 1425 | read_unlock(&journal->j_state_lock); |
Josef Bacik | e07f718 | 2008-11-26 01:14:26 -0500 | [diff] [blame] | 1426 | |
| 1427 | trans_time = ktime_to_ns(ktime_sub(ktime_get(), |
| 1428 | transaction->t_start_time)); |
| 1429 | |
Theodore Ts'o | 3077384 | 2009-01-03 20:27:38 -0500 | [diff] [blame] | 1430 | commit_time = max_t(u64, commit_time, |
| 1431 | 1000*journal->j_min_batch_time); |
Josef Bacik | e07f718 | 2008-11-26 01:14:26 -0500 | [diff] [blame] | 1432 | commit_time = min_t(u64, commit_time, |
Theodore Ts'o | 3077384 | 2009-01-03 20:27:38 -0500 | [diff] [blame] | 1433 | 1000*journal->j_max_batch_time); |
Josef Bacik | e07f718 | 2008-11-26 01:14:26 -0500 | [diff] [blame] | 1434 | |
| 1435 | if (trans_time < commit_time) { |
| 1436 | ktime_t expires = ktime_add_ns(ktime_get(), |
| 1437 | commit_time); |
| 1438 | set_current_state(TASK_UNINTERRUPTIBLE); |
| 1439 | schedule_hrtimeout(&expires, HRTIMER_MODE_ABS); |
| 1440 | } |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1441 | } |
| 1442 | |
Theodore Ts'o | 7058548 | 2009-03-25 23:35:46 -0400 | [diff] [blame] | 1443 | if (handle->h_sync) |
| 1444 | transaction->t_synchronous_commit = 1; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1445 | current->journal_info = NULL; |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 1446 | atomic_sub(handle->h_buffer_credits, |
| 1447 | &transaction->t_outstanding_credits); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1448 | |
| 1449 | /* |
| 1450 | * If the handle is marked SYNC, we need to set another commit |
| 1451 | * going! We also want to force a commit if the current |
| 1452 | * transaction is occupying too much of the log, or if the |
| 1453 | * transaction is too old now. |
| 1454 | */ |
| 1455 | if (handle->h_sync || |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 1456 | (atomic_read(&transaction->t_outstanding_credits) > |
| 1457 | journal->j_max_transaction_buffers) || |
| 1458 | time_after_eq(jiffies, transaction->t_expires)) { |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1459 | /* Do this even for aborted journals: an abort still |
| 1460 | * completes the commit thread, it just doesn't write |
| 1461 | * anything to disk. */ |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1462 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1463 | jbd_debug(2, "transaction too old, requesting commit for " |
| 1464 | "handle %p\n", handle); |
| 1465 | /* This is non-blocking */ |
Theodore Ts'o | c35a56a | 2010-05-16 05:00:00 -0400 | [diff] [blame] | 1466 | jbd2_log_start_commit(journal, transaction->t_tid); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1467 | |
| 1468 | /* |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1469 | * Special case: JBD2_SYNC synchronous updates require us |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1470 | * to wait for the commit to complete. |
| 1471 | */ |
| 1472 | if (handle->h_sync && !(current->flags & PF_MEMALLOC)) |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 1473 | wait_for_commit = 1; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1474 | } |
| 1475 | |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 1476 | /* |
| 1477 | * Once we drop t_updates, if it goes to zero the transaction |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 1478 | * could start committing on us and eventually disappear. So |
Theodore Ts'o | a51dca9 | 2010-08-02 08:43:25 -0400 | [diff] [blame] | 1479 | * once we do this, we must not dereference transaction |
| 1480 | * pointer again. |
| 1481 | */ |
| 1482 | tid = transaction->t_tid; |
| 1483 | if (atomic_dec_and_test(&transaction->t_updates)) { |
| 1484 | wake_up(&journal->j_wait_updates); |
| 1485 | if (journal->j_barrier_count) |
| 1486 | wake_up(&journal->j_wait_transaction_locked); |
| 1487 | } |
| 1488 | |
| 1489 | if (wait_for_commit) |
| 1490 | err = jbd2_log_wait_commit(journal, tid); |
| 1491 | |
Ingo Molnar | 3295f0e | 2008-08-11 10:30:30 +0200 | [diff] [blame] | 1492 | lock_map_release(&handle->h_lockdep_map); |
Mingming Cao | 7b75106 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 1493 | |
Mingming Cao | af1e76d | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 1494 | jbd2_free_handle(handle); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1495 | return err; |
| 1496 | } |
| 1497 | |
Randy Dunlap | 5648ba5 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 1498 | /** |
| 1499 | * int jbd2_journal_force_commit() - force any uncommitted transactions |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1500 | * @journal: journal to force |
| 1501 | * |
| 1502 | * For synchronous operations: force any uncommitted transactions |
| 1503 | * to disk. May seem kludgy, but it reuses all the handle batching |
| 1504 | * code in a very simple manner. |
| 1505 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1506 | int jbd2_journal_force_commit(journal_t *journal) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1507 | { |
| 1508 | handle_t *handle; |
| 1509 | int ret; |
| 1510 | |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1511 | handle = jbd2_journal_start(journal, 1); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1512 | if (IS_ERR(handle)) { |
| 1513 | ret = PTR_ERR(handle); |
| 1514 | } else { |
| 1515 | handle->h_sync = 1; |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1516 | ret = jbd2_journal_stop(handle); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1517 | } |
| 1518 | return ret; |
| 1519 | } |
| 1520 | |
| 1521 | /* |
| 1522 | * |
| 1523 | * List management code snippets: various functions for manipulating the |
| 1524 | * transaction buffer lists. |
| 1525 | * |
| 1526 | */ |
| 1527 | |
| 1528 | /* |
| 1529 | * Append a buffer to a transaction list, given the transaction's list head |
| 1530 | * pointer. |
| 1531 | * |
| 1532 | * j_list_lock is held. |
| 1533 | * |
| 1534 | * jbd_lock_bh_state(jh2bh(jh)) is held. |
| 1535 | */ |
| 1536 | |
| 1537 | static inline void |
| 1538 | __blist_add_buffer(struct journal_head **list, struct journal_head *jh) |
| 1539 | { |
| 1540 | if (!*list) { |
| 1541 | jh->b_tnext = jh->b_tprev = jh; |
| 1542 | *list = jh; |
| 1543 | } else { |
| 1544 | /* Insert at the tail of the list to preserve order */ |
| 1545 | struct journal_head *first = *list, *last = first->b_tprev; |
| 1546 | jh->b_tprev = last; |
| 1547 | jh->b_tnext = first; |
| 1548 | last->b_tnext = first->b_tprev = jh; |
| 1549 | } |
| 1550 | } |
| 1551 | |
| 1552 | /* |
| 1553 | * Remove a buffer from a transaction list, given the transaction's list |
| 1554 | * head pointer. |
| 1555 | * |
| 1556 | * Called with j_list_lock held, and the journal may not be locked. |
| 1557 | * |
| 1558 | * jbd_lock_bh_state(jh2bh(jh)) is held. |
| 1559 | */ |
| 1560 | |
| 1561 | static inline void |
| 1562 | __blist_del_buffer(struct journal_head **list, struct journal_head *jh) |
| 1563 | { |
| 1564 | if (*list == jh) { |
| 1565 | *list = jh->b_tnext; |
| 1566 | if (*list == jh) |
| 1567 | *list = NULL; |
| 1568 | } |
| 1569 | jh->b_tprev->b_tnext = jh->b_tnext; |
| 1570 | jh->b_tnext->b_tprev = jh->b_tprev; |
| 1571 | } |
| 1572 | |
| 1573 | /* |
| 1574 | * Remove a buffer from the appropriate transaction list. |
| 1575 | * |
| 1576 | * Note that this function can *change* the value of |
Jan Kara | 87c89c2 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 1577 | * bh->b_transaction->t_buffers, t_forget, t_iobuf_list, t_shadow_list, |
| 1578 | * t_log_list or t_reserved_list. If the caller is holding onto a copy of one |
| 1579 | * of these pointers, it could go bad. Generally the caller needs to re-read |
| 1580 | * the pointer from the transaction_t. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1581 | * |
Jan Kara | 5bebccf | 2012-03-13 22:25:06 -0400 | [diff] [blame] | 1582 | * Called under j_list_lock. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1583 | */ |
Jan Kara | 5bebccf | 2012-03-13 22:25:06 -0400 | [diff] [blame] | 1584 | static void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1585 | { |
| 1586 | struct journal_head **list = NULL; |
| 1587 | transaction_t *transaction; |
| 1588 | struct buffer_head *bh = jh2bh(jh); |
| 1589 | |
| 1590 | J_ASSERT_JH(jh, jbd_is_locked_bh_state(bh)); |
| 1591 | transaction = jh->b_transaction; |
| 1592 | if (transaction) |
| 1593 | assert_spin_locked(&transaction->t_journal->j_list_lock); |
| 1594 | |
| 1595 | J_ASSERT_JH(jh, jh->b_jlist < BJ_Types); |
| 1596 | if (jh->b_jlist != BJ_None) |
Mingming Cao | 4019191 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 1597 | J_ASSERT_JH(jh, transaction != NULL); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1598 | |
| 1599 | switch (jh->b_jlist) { |
| 1600 | case BJ_None: |
| 1601 | return; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1602 | case BJ_Metadata: |
| 1603 | transaction->t_nr_buffers--; |
| 1604 | J_ASSERT_JH(jh, transaction->t_nr_buffers >= 0); |
| 1605 | list = &transaction->t_buffers; |
| 1606 | break; |
| 1607 | case BJ_Forget: |
| 1608 | list = &transaction->t_forget; |
| 1609 | break; |
| 1610 | case BJ_IO: |
| 1611 | list = &transaction->t_iobuf_list; |
| 1612 | break; |
| 1613 | case BJ_Shadow: |
| 1614 | list = &transaction->t_shadow_list; |
| 1615 | break; |
| 1616 | case BJ_LogCtl: |
| 1617 | list = &transaction->t_log_list; |
| 1618 | break; |
| 1619 | case BJ_Reserved: |
| 1620 | list = &transaction->t_reserved_list; |
| 1621 | break; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1622 | } |
| 1623 | |
| 1624 | __blist_del_buffer(list, jh); |
| 1625 | jh->b_jlist = BJ_None; |
| 1626 | if (test_clear_buffer_jbddirty(bh)) |
| 1627 | mark_buffer_dirty(bh); /* Expose it to the VM */ |
| 1628 | } |
| 1629 | |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 1630 | /* |
| 1631 | * Remove buffer from all transactions. |
| 1632 | * |
| 1633 | * Called with bh_state lock and j_list_lock |
| 1634 | * |
| 1635 | * jh and bh may be already freed when this function returns. |
| 1636 | */ |
| 1637 | static void __jbd2_journal_unfile_buffer(struct journal_head *jh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1638 | { |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1639 | __jbd2_journal_temp_unlink_buffer(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1640 | jh->b_transaction = NULL; |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 1641 | jbd2_journal_put_journal_head(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1642 | } |
| 1643 | |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1644 | void jbd2_journal_unfile_buffer(journal_t *journal, struct journal_head *jh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1645 | { |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 1646 | struct buffer_head *bh = jh2bh(jh); |
| 1647 | |
| 1648 | /* Get reference so that buffer cannot be freed before we unlock it */ |
| 1649 | get_bh(bh); |
| 1650 | jbd_lock_bh_state(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1651 | spin_lock(&journal->j_list_lock); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1652 | __jbd2_journal_unfile_buffer(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1653 | spin_unlock(&journal->j_list_lock); |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 1654 | jbd_unlock_bh_state(bh); |
| 1655 | __brelse(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1656 | } |
| 1657 | |
| 1658 | /* |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1659 | * Called from jbd2_journal_try_to_free_buffers(). |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1660 | * |
| 1661 | * Called under jbd_lock_bh_state(bh) |
| 1662 | */ |
| 1663 | static void |
| 1664 | __journal_try_to_free_buffer(journal_t *journal, struct buffer_head *bh) |
| 1665 | { |
| 1666 | struct journal_head *jh; |
| 1667 | |
| 1668 | jh = bh2jh(bh); |
| 1669 | |
| 1670 | if (buffer_locked(bh) || buffer_dirty(bh)) |
| 1671 | goto out; |
| 1672 | |
Mingming Cao | 4019191 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 1673 | if (jh->b_next_transaction != NULL) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1674 | goto out; |
| 1675 | |
| 1676 | spin_lock(&journal->j_list_lock); |
Jan Kara | 87c89c2 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 1677 | if (jh->b_cp_transaction != NULL && jh->b_transaction == NULL) { |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1678 | /* written-back checkpointed metadata buffer */ |
Jan Kara | c254c9e | 2012-03-13 22:27:44 -0400 | [diff] [blame] | 1679 | JBUFFER_TRACE(jh, "remove from checkpoint list"); |
| 1680 | __jbd2_journal_remove_checkpoint(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1681 | } |
| 1682 | spin_unlock(&journal->j_list_lock); |
| 1683 | out: |
| 1684 | return; |
| 1685 | } |
| 1686 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1687 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1688 | * int jbd2_journal_try_to_free_buffers() - try to free page buffers. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1689 | * @journal: journal for operation |
| 1690 | * @page: to try and free |
Mingming Cao | 530576b | 2008-07-13 21:06:39 -0400 | [diff] [blame] | 1691 | * @gfp_mask: we use the mask to detect how hard should we try to release |
| 1692 | * buffers. If __GFP_WAIT and __GFP_FS is set, we wait for commit code to |
| 1693 | * release the buffers. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1694 | * |
| 1695 | * |
| 1696 | * For all the buffers on this page, |
| 1697 | * if they are fully written out ordered data, move them onto BUF_CLEAN |
| 1698 | * so try_to_free_buffers() can reap them. |
| 1699 | * |
| 1700 | * This function returns non-zero if we wish try_to_free_buffers() |
| 1701 | * to be called. We do this if the page is releasable by try_to_free_buffers(). |
| 1702 | * We also do it if the page has locked or dirty buffers and the caller wants |
| 1703 | * us to perform sync or async writeout. |
| 1704 | * |
| 1705 | * This complicates JBD locking somewhat. We aren't protected by the |
| 1706 | * BKL here. We wish to remove the buffer from its committing or |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1707 | * running transaction's ->t_datalist via __jbd2_journal_unfile_buffer. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1708 | * |
| 1709 | * This may *change* the value of transaction_t->t_datalist, so anyone |
| 1710 | * who looks at t_datalist needs to lock against this function. |
| 1711 | * |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1712 | * Even worse, someone may be doing a jbd2_journal_dirty_data on this |
| 1713 | * buffer. So we need to lock against that. jbd2_journal_dirty_data() |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1714 | * will come out of the lock with the buffer dirty, which makes it |
| 1715 | * ineligible for release here. |
| 1716 | * |
| 1717 | * Who else is affected by this? hmm... Really the only contender |
| 1718 | * is do_get_write_access() - it could be looking at the buffer while |
| 1719 | * journal_try_to_free_buffer() is changing its state. But that |
| 1720 | * cannot happen because we never reallocate freed data as metadata |
| 1721 | * while the data is part of a transaction. Yes? |
Mingming Cao | 530576b | 2008-07-13 21:06:39 -0400 | [diff] [blame] | 1722 | * |
| 1723 | * Return 0 on failure, 1 on success |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1724 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1725 | int jbd2_journal_try_to_free_buffers(journal_t *journal, |
Mingming Cao | 530576b | 2008-07-13 21:06:39 -0400 | [diff] [blame] | 1726 | struct page *page, gfp_t gfp_mask) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1727 | { |
| 1728 | struct buffer_head *head; |
| 1729 | struct buffer_head *bh; |
| 1730 | int ret = 0; |
| 1731 | |
| 1732 | J_ASSERT(PageLocked(page)); |
| 1733 | |
| 1734 | head = page_buffers(page); |
| 1735 | bh = head; |
| 1736 | do { |
| 1737 | struct journal_head *jh; |
| 1738 | |
| 1739 | /* |
| 1740 | * We take our own ref against the journal_head here to avoid |
| 1741 | * having to add tons of locking around each instance of |
Mingming Cao | 530576b | 2008-07-13 21:06:39 -0400 | [diff] [blame] | 1742 | * jbd2_journal_put_journal_head(). |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1743 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1744 | jh = jbd2_journal_grab_journal_head(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1745 | if (!jh) |
| 1746 | continue; |
| 1747 | |
| 1748 | jbd_lock_bh_state(bh); |
| 1749 | __journal_try_to_free_buffer(journal, bh); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1750 | jbd2_journal_put_journal_head(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1751 | jbd_unlock_bh_state(bh); |
| 1752 | if (buffer_jbd(bh)) |
| 1753 | goto busy; |
| 1754 | } while ((bh = bh->b_this_page) != head); |
Mingming Cao | 530576b | 2008-07-13 21:06:39 -0400 | [diff] [blame] | 1755 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1756 | ret = try_to_free_buffers(page); |
Mingming Cao | 530576b | 2008-07-13 21:06:39 -0400 | [diff] [blame] | 1757 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1758 | busy: |
| 1759 | return ret; |
| 1760 | } |
| 1761 | |
| 1762 | /* |
| 1763 | * This buffer is no longer needed. If it is on an older transaction's |
| 1764 | * checkpoint list we need to record it on this transaction's forget list |
| 1765 | * to pin this buffer (and hence its checkpointing transaction) down until |
| 1766 | * this transaction commits. If the buffer isn't on a checkpoint list, we |
| 1767 | * release it. |
| 1768 | * Returns non-zero if JBD no longer has an interest in the buffer. |
| 1769 | * |
| 1770 | * Called under j_list_lock. |
| 1771 | * |
| 1772 | * Called under jbd_lock_bh_state(bh). |
| 1773 | */ |
| 1774 | static int __dispose_buffer(struct journal_head *jh, transaction_t *transaction) |
| 1775 | { |
| 1776 | int may_free = 1; |
| 1777 | struct buffer_head *bh = jh2bh(jh); |
| 1778 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1779 | if (jh->b_cp_transaction) { |
| 1780 | JBUFFER_TRACE(jh, "on running+cp transaction"); |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 1781 | __jbd2_journal_temp_unlink_buffer(jh); |
Jan Kara | f91d1d0 | 2009-07-13 16:16:20 -0400 | [diff] [blame] | 1782 | /* |
| 1783 | * We don't want to write the buffer anymore, clear the |
| 1784 | * bit so that we don't confuse checks in |
| 1785 | * __journal_file_buffer |
| 1786 | */ |
| 1787 | clear_buffer_dirty(bh); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1788 | __jbd2_journal_file_buffer(jh, transaction, BJ_Forget); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1789 | may_free = 0; |
| 1790 | } else { |
| 1791 | JBUFFER_TRACE(jh, "on running transaction"); |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 1792 | __jbd2_journal_unfile_buffer(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1793 | } |
| 1794 | return may_free; |
| 1795 | } |
| 1796 | |
| 1797 | /* |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1798 | * jbd2_journal_invalidatepage |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1799 | * |
| 1800 | * This code is tricky. It has a number of cases to deal with. |
| 1801 | * |
| 1802 | * There are two invariants which this code relies on: |
| 1803 | * |
| 1804 | * i_size must be updated on disk before we start calling invalidatepage on the |
| 1805 | * data. |
| 1806 | * |
| 1807 | * This is done in ext3 by defining an ext3_setattr method which |
| 1808 | * updates i_size before truncate gets going. By maintaining this |
| 1809 | * invariant, we can be sure that it is safe to throw away any buffers |
| 1810 | * attached to the current transaction: once the transaction commits, |
| 1811 | * we know that the data will not be needed. |
| 1812 | * |
| 1813 | * Note however that we can *not* throw away data belonging to the |
| 1814 | * previous, committing transaction! |
| 1815 | * |
| 1816 | * Any disk blocks which *are* part of the previous, committing |
| 1817 | * transaction (and which therefore cannot be discarded immediately) are |
| 1818 | * not going to be reused in the new running transaction |
| 1819 | * |
| 1820 | * The bitmap committed_data images guarantee this: any block which is |
| 1821 | * allocated in one transaction and removed in the next will be marked |
| 1822 | * as in-use in the committed_data bitmap, so cannot be reused until |
| 1823 | * the next transaction to delete the block commits. This means that |
| 1824 | * leaving committing buffers dirty is quite safe: the disk blocks |
| 1825 | * cannot be reallocated to a different file and so buffer aliasing is |
| 1826 | * not possible. |
| 1827 | * |
| 1828 | * |
| 1829 | * The above applies mainly to ordered data mode. In writeback mode we |
| 1830 | * don't make guarantees about the order in which data hits disk --- in |
| 1831 | * particular we don't guarantee that new dirty data is flushed before |
| 1832 | * transaction commit --- so it is always safe just to discard data |
| 1833 | * immediately in that mode. --sct |
| 1834 | */ |
| 1835 | |
| 1836 | /* |
| 1837 | * The journal_unmap_buffer helper function returns zero if the buffer |
| 1838 | * concerned remains pinned as an anonymous buffer belonging to an older |
| 1839 | * transaction. |
| 1840 | * |
| 1841 | * We're outside-transaction here. Either or both of j_running_transaction |
| 1842 | * and j_committing_transaction may be NULL. |
| 1843 | */ |
| 1844 | static int journal_unmap_buffer(journal_t *journal, struct buffer_head *bh) |
| 1845 | { |
| 1846 | transaction_t *transaction; |
| 1847 | struct journal_head *jh; |
| 1848 | int may_free = 1; |
| 1849 | int ret; |
| 1850 | |
| 1851 | BUFFER_TRACE(bh, "entry"); |
| 1852 | |
| 1853 | /* |
| 1854 | * It is safe to proceed here without the j_list_lock because the |
| 1855 | * buffers cannot be stolen by try_to_free_buffers as long as we are |
| 1856 | * holding the page lock. --sct |
| 1857 | */ |
| 1858 | |
| 1859 | if (!buffer_jbd(bh)) |
| 1860 | goto zap_buffer_unlocked; |
| 1861 | |
Jan Kara | 87c89c2 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 1862 | /* OK, we have data buffer in journaled mode */ |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 1863 | write_lock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1864 | jbd_lock_bh_state(bh); |
| 1865 | spin_lock(&journal->j_list_lock); |
| 1866 | |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1867 | jh = jbd2_journal_grab_journal_head(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1868 | if (!jh) |
| 1869 | goto zap_buffer_no_jh; |
| 1870 | |
dingdinghua | ba86902 | 2010-02-15 16:35:42 -0500 | [diff] [blame] | 1871 | /* |
| 1872 | * We cannot remove the buffer from checkpoint lists until the |
| 1873 | * transaction adding inode to orphan list (let's call it T) |
| 1874 | * is committed. Otherwise if the transaction changing the |
| 1875 | * buffer would be cleaned from the journal before T is |
| 1876 | * committed, a crash will cause that the correct contents of |
| 1877 | * the buffer will be lost. On the other hand we have to |
| 1878 | * clear the buffer dirty bit at latest at the moment when the |
| 1879 | * transaction marking the buffer as freed in the filesystem |
| 1880 | * structures is committed because from that moment on the |
| 1881 | * buffer can be reallocated and used by a different page. |
| 1882 | * Since the block hasn't been freed yet but the inode has |
| 1883 | * already been added to orphan list, it is safe for us to add |
| 1884 | * the buffer to BJ_Forget list of the newest transaction. |
| 1885 | */ |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1886 | transaction = jh->b_transaction; |
| 1887 | if (transaction == NULL) { |
| 1888 | /* First case: not on any transaction. If it |
| 1889 | * has no checkpoint link, then we can zap it: |
| 1890 | * it's a writeback-mode buffer so we don't care |
| 1891 | * if it hits disk safely. */ |
| 1892 | if (!jh->b_cp_transaction) { |
| 1893 | JBUFFER_TRACE(jh, "not on any transaction: zap"); |
| 1894 | goto zap_buffer; |
| 1895 | } |
| 1896 | |
| 1897 | if (!buffer_dirty(bh)) { |
| 1898 | /* bdflush has written it. We can drop it now */ |
| 1899 | goto zap_buffer; |
| 1900 | } |
| 1901 | |
| 1902 | /* OK, it must be in the journal but still not |
| 1903 | * written fully to disk: it's metadata or |
| 1904 | * journaled data... */ |
| 1905 | |
| 1906 | if (journal->j_running_transaction) { |
| 1907 | /* ... and once the current transaction has |
| 1908 | * committed, the buffer won't be needed any |
| 1909 | * longer. */ |
| 1910 | JBUFFER_TRACE(jh, "checkpointed: add to BJ_Forget"); |
| 1911 | ret = __dispose_buffer(jh, |
| 1912 | journal->j_running_transaction); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1913 | jbd2_journal_put_journal_head(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1914 | spin_unlock(&journal->j_list_lock); |
| 1915 | jbd_unlock_bh_state(bh); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 1916 | write_unlock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1917 | return ret; |
| 1918 | } else { |
| 1919 | /* There is no currently-running transaction. So the |
| 1920 | * orphan record which we wrote for this file must have |
| 1921 | * passed into commit. We must attach this buffer to |
| 1922 | * the committing transaction, if it exists. */ |
| 1923 | if (journal->j_committing_transaction) { |
| 1924 | JBUFFER_TRACE(jh, "give to committing trans"); |
| 1925 | ret = __dispose_buffer(jh, |
| 1926 | journal->j_committing_transaction); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1927 | jbd2_journal_put_journal_head(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1928 | spin_unlock(&journal->j_list_lock); |
| 1929 | jbd_unlock_bh_state(bh); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 1930 | write_unlock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1931 | return ret; |
| 1932 | } else { |
| 1933 | /* The orphan record's transaction has |
| 1934 | * committed. We can cleanse this buffer */ |
| 1935 | clear_buffer_jbddirty(bh); |
| 1936 | goto zap_buffer; |
| 1937 | } |
| 1938 | } |
| 1939 | } else if (transaction == journal->j_committing_transaction) { |
Eric Sandeen | 9b57988 | 2006-10-28 10:38:28 -0700 | [diff] [blame] | 1940 | JBUFFER_TRACE(jh, "on committing transaction"); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1941 | /* |
dingdinghua | ba86902 | 2010-02-15 16:35:42 -0500 | [diff] [blame] | 1942 | * The buffer is committing, we simply cannot touch |
| 1943 | * it. So we just set j_next_transaction to the |
| 1944 | * running transaction (if there is one) and mark |
| 1945 | * buffer as freed so that commit code knows it should |
| 1946 | * clear dirty bits when it is done with the buffer. |
| 1947 | */ |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1948 | set_buffer_freed(bh); |
dingdinghua | ba86902 | 2010-02-15 16:35:42 -0500 | [diff] [blame] | 1949 | if (journal->j_running_transaction && buffer_jbddirty(bh)) |
| 1950 | jh->b_next_transaction = journal->j_running_transaction; |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1951 | jbd2_journal_put_journal_head(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1952 | spin_unlock(&journal->j_list_lock); |
| 1953 | jbd_unlock_bh_state(bh); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 1954 | write_unlock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1955 | return 0; |
| 1956 | } else { |
| 1957 | /* Good, the buffer belongs to the running transaction. |
| 1958 | * We are writing our own transaction's data, not any |
| 1959 | * previous one's, so it is safe to throw it away |
| 1960 | * (remember that we expect the filesystem to have set |
| 1961 | * i_size already for this truncate so recovery will not |
| 1962 | * expose the disk blocks we are discarding here.) */ |
| 1963 | J_ASSERT_JH(jh, transaction == journal->j_running_transaction); |
Eric Sandeen | 9b57988 | 2006-10-28 10:38:28 -0700 | [diff] [blame] | 1964 | JBUFFER_TRACE(jh, "on running transaction"); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1965 | may_free = __dispose_buffer(jh, transaction); |
| 1966 | } |
| 1967 | |
| 1968 | zap_buffer: |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1969 | jbd2_journal_put_journal_head(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1970 | zap_buffer_no_jh: |
| 1971 | spin_unlock(&journal->j_list_lock); |
| 1972 | jbd_unlock_bh_state(bh); |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 1973 | write_unlock(&journal->j_state_lock); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1974 | zap_buffer_unlocked: |
| 1975 | clear_buffer_dirty(bh); |
| 1976 | J_ASSERT_BH(bh, !buffer_jbddirty(bh)); |
| 1977 | clear_buffer_mapped(bh); |
| 1978 | clear_buffer_req(bh); |
| 1979 | clear_buffer_new(bh); |
Eric Sandeen | 1529116 | 2012-02-20 17:53:01 -0500 | [diff] [blame] | 1980 | clear_buffer_delay(bh); |
| 1981 | clear_buffer_unwritten(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1982 | bh->b_bdev = NULL; |
| 1983 | return may_free; |
| 1984 | } |
| 1985 | |
| 1986 | /** |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1987 | * void jbd2_journal_invalidatepage() |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1988 | * @journal: journal to use for flush... |
| 1989 | * @page: page to flush |
| 1990 | * @offset: length of page to invalidate. |
| 1991 | * |
| 1992 | * Reap page buffers containing data after offset in page. |
| 1993 | * |
| 1994 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 1995 | void jbd2_journal_invalidatepage(journal_t *journal, |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 1996 | struct page *page, |
| 1997 | unsigned long offset) |
| 1998 | { |
| 1999 | struct buffer_head *head, *bh, *next; |
| 2000 | unsigned int curr_off = 0; |
| 2001 | int may_free = 1; |
| 2002 | |
| 2003 | if (!PageLocked(page)) |
| 2004 | BUG(); |
| 2005 | if (!page_has_buffers(page)) |
| 2006 | return; |
| 2007 | |
| 2008 | /* We will potentially be playing with lists other than just the |
| 2009 | * data lists (especially for journaled data mode), so be |
| 2010 | * cautious in our locking. */ |
| 2011 | |
| 2012 | head = bh = page_buffers(page); |
| 2013 | do { |
| 2014 | unsigned int next_off = curr_off + bh->b_size; |
| 2015 | next = bh->b_this_page; |
| 2016 | |
| 2017 | if (offset <= curr_off) { |
| 2018 | /* This block is wholly outside the truncation point */ |
| 2019 | lock_buffer(bh); |
| 2020 | may_free &= journal_unmap_buffer(journal, bh); |
| 2021 | unlock_buffer(bh); |
| 2022 | } |
| 2023 | curr_off = next_off; |
| 2024 | bh = next; |
| 2025 | |
| 2026 | } while (bh != head); |
| 2027 | |
| 2028 | if (!offset) { |
| 2029 | if (may_free && try_to_free_buffers(page)) |
| 2030 | J_ASSERT(!page_has_buffers(page)); |
| 2031 | } |
| 2032 | } |
| 2033 | |
| 2034 | /* |
| 2035 | * File a buffer on the given transaction list. |
| 2036 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 2037 | void __jbd2_journal_file_buffer(struct journal_head *jh, |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2038 | transaction_t *transaction, int jlist) |
| 2039 | { |
| 2040 | struct journal_head **list = NULL; |
| 2041 | int was_dirty = 0; |
| 2042 | struct buffer_head *bh = jh2bh(jh); |
| 2043 | |
| 2044 | J_ASSERT_JH(jh, jbd_is_locked_bh_state(bh)); |
| 2045 | assert_spin_locked(&transaction->t_journal->j_list_lock); |
| 2046 | |
| 2047 | J_ASSERT_JH(jh, jh->b_jlist < BJ_Types); |
| 2048 | J_ASSERT_JH(jh, jh->b_transaction == transaction || |
Mingming Cao | 4019191 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 2049 | jh->b_transaction == NULL); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2050 | |
| 2051 | if (jh->b_transaction && jh->b_jlist == jlist) |
| 2052 | return; |
| 2053 | |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2054 | if (jlist == BJ_Metadata || jlist == BJ_Reserved || |
| 2055 | jlist == BJ_Shadow || jlist == BJ_Forget) { |
Jan Kara | f91d1d0 | 2009-07-13 16:16:20 -0400 | [diff] [blame] | 2056 | /* |
| 2057 | * For metadata buffers, we track dirty bit in buffer_jbddirty |
| 2058 | * instead of buffer_dirty. We should not see a dirty bit set |
| 2059 | * here because we clear it in do_get_write_access but e.g. |
| 2060 | * tune2fs can modify the sb and set the dirty bit at any time |
| 2061 | * so we try to gracefully handle that. |
| 2062 | */ |
| 2063 | if (buffer_dirty(bh)) |
| 2064 | warn_dirty_buffer(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2065 | if (test_clear_buffer_dirty(bh) || |
| 2066 | test_clear_buffer_jbddirty(bh)) |
| 2067 | was_dirty = 1; |
| 2068 | } |
| 2069 | |
| 2070 | if (jh->b_transaction) |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 2071 | __jbd2_journal_temp_unlink_buffer(jh); |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 2072 | else |
| 2073 | jbd2_journal_grab_journal_head(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2074 | jh->b_transaction = transaction; |
| 2075 | |
| 2076 | switch (jlist) { |
| 2077 | case BJ_None: |
| 2078 | J_ASSERT_JH(jh, !jh->b_committed_data); |
| 2079 | J_ASSERT_JH(jh, !jh->b_frozen_data); |
| 2080 | return; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2081 | case BJ_Metadata: |
| 2082 | transaction->t_nr_buffers++; |
| 2083 | list = &transaction->t_buffers; |
| 2084 | break; |
| 2085 | case BJ_Forget: |
| 2086 | list = &transaction->t_forget; |
| 2087 | break; |
| 2088 | case BJ_IO: |
| 2089 | list = &transaction->t_iobuf_list; |
| 2090 | break; |
| 2091 | case BJ_Shadow: |
| 2092 | list = &transaction->t_shadow_list; |
| 2093 | break; |
| 2094 | case BJ_LogCtl: |
| 2095 | list = &transaction->t_log_list; |
| 2096 | break; |
| 2097 | case BJ_Reserved: |
| 2098 | list = &transaction->t_reserved_list; |
| 2099 | break; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2100 | } |
| 2101 | |
| 2102 | __blist_add_buffer(list, jh); |
| 2103 | jh->b_jlist = jlist; |
| 2104 | |
| 2105 | if (was_dirty) |
| 2106 | set_buffer_jbddirty(bh); |
| 2107 | } |
| 2108 | |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 2109 | void jbd2_journal_file_buffer(struct journal_head *jh, |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2110 | transaction_t *transaction, int jlist) |
| 2111 | { |
| 2112 | jbd_lock_bh_state(jh2bh(jh)); |
| 2113 | spin_lock(&transaction->t_journal->j_list_lock); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 2114 | __jbd2_journal_file_buffer(jh, transaction, jlist); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2115 | spin_unlock(&transaction->t_journal->j_list_lock); |
| 2116 | jbd_unlock_bh_state(jh2bh(jh)); |
| 2117 | } |
| 2118 | |
| 2119 | /* |
| 2120 | * Remove a buffer from its current buffer list in preparation for |
| 2121 | * dropping it from its current transaction entirely. If the buffer has |
| 2122 | * already started to be used by a subsequent transaction, refile the |
| 2123 | * buffer on that transaction's metadata list. |
| 2124 | * |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 2125 | * Called under j_list_lock |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2126 | * Called under jbd_lock_bh_state(jh2bh(jh)) |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 2127 | * |
| 2128 | * jh and bh may be already free when this function returns |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2129 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 2130 | void __jbd2_journal_refile_buffer(struct journal_head *jh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2131 | { |
dingdinghua | ba86902 | 2010-02-15 16:35:42 -0500 | [diff] [blame] | 2132 | int was_dirty, jlist; |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2133 | struct buffer_head *bh = jh2bh(jh); |
| 2134 | |
| 2135 | J_ASSERT_JH(jh, jbd_is_locked_bh_state(bh)); |
| 2136 | if (jh->b_transaction) |
| 2137 | assert_spin_locked(&jh->b_transaction->t_journal->j_list_lock); |
| 2138 | |
| 2139 | /* If the buffer is now unused, just drop it. */ |
| 2140 | if (jh->b_next_transaction == NULL) { |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 2141 | __jbd2_journal_unfile_buffer(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2142 | return; |
| 2143 | } |
| 2144 | |
| 2145 | /* |
| 2146 | * It has been modified by a later transaction: add it to the new |
| 2147 | * transaction's metadata list. |
| 2148 | */ |
| 2149 | |
| 2150 | was_dirty = test_clear_buffer_jbddirty(bh); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 2151 | __jbd2_journal_temp_unlink_buffer(jh); |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 2152 | /* |
| 2153 | * We set b_transaction here because b_next_transaction will inherit |
| 2154 | * our jh reference and thus __jbd2_journal_file_buffer() must not |
| 2155 | * take a new one. |
| 2156 | */ |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2157 | jh->b_transaction = jh->b_next_transaction; |
| 2158 | jh->b_next_transaction = NULL; |
dingdinghua | ba86902 | 2010-02-15 16:35:42 -0500 | [diff] [blame] | 2159 | if (buffer_freed(bh)) |
| 2160 | jlist = BJ_Forget; |
| 2161 | else if (jh->b_modified) |
| 2162 | jlist = BJ_Metadata; |
| 2163 | else |
| 2164 | jlist = BJ_Reserved; |
| 2165 | __jbd2_journal_file_buffer(jh, jh->b_transaction, jlist); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2166 | J_ASSERT_JH(jh, jh->b_transaction->t_state == T_RUNNING); |
| 2167 | |
| 2168 | if (was_dirty) |
| 2169 | set_buffer_jbddirty(bh); |
| 2170 | } |
| 2171 | |
| 2172 | /* |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 2173 | * __jbd2_journal_refile_buffer() with necessary locking added. We take our |
| 2174 | * bh reference so that we can safely unlock bh. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2175 | * |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 2176 | * The jh and bh may be freed by this call. |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2177 | */ |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 2178 | void jbd2_journal_refile_buffer(journal_t *journal, struct journal_head *jh) |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2179 | { |
| 2180 | struct buffer_head *bh = jh2bh(jh); |
| 2181 | |
Jan Kara | de1b794 | 2011-06-13 15:38:22 -0400 | [diff] [blame] | 2182 | /* Get reference so that buffer cannot be freed before we unlock it */ |
| 2183 | get_bh(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2184 | jbd_lock_bh_state(bh); |
| 2185 | spin_lock(&journal->j_list_lock); |
Mingming Cao | f7f4bcc | 2006-10-11 01:20:59 -0700 | [diff] [blame] | 2186 | __jbd2_journal_refile_buffer(jh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2187 | jbd_unlock_bh_state(bh); |
Dave Kleikamp | 470decc | 2006-10-11 01:20:57 -0700 | [diff] [blame] | 2188 | spin_unlock(&journal->j_list_lock); |
| 2189 | __brelse(bh); |
| 2190 | } |
Jan Kara | c851ed5 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 2191 | |
| 2192 | /* |
| 2193 | * File inode in the inode list of the handle's transaction |
| 2194 | */ |
| 2195 | int jbd2_journal_file_inode(handle_t *handle, struct jbd2_inode *jinode) |
| 2196 | { |
| 2197 | transaction_t *transaction = handle->h_transaction; |
| 2198 | journal_t *journal = transaction->t_journal; |
| 2199 | |
| 2200 | if (is_handle_aborted(handle)) |
| 2201 | return -EIO; |
| 2202 | |
| 2203 | jbd_debug(4, "Adding inode %lu, tid:%d\n", jinode->i_vfs_inode->i_ino, |
| 2204 | transaction->t_tid); |
| 2205 | |
| 2206 | /* |
| 2207 | * First check whether inode isn't already on the transaction's |
| 2208 | * lists without taking the lock. Note that this check is safe |
| 2209 | * without the lock as we cannot race with somebody removing inode |
| 2210 | * from the transaction. The reason is that we remove inode from the |
| 2211 | * transaction only in journal_release_jbd_inode() and when we commit |
| 2212 | * the transaction. We are guarded from the first case by holding |
| 2213 | * a reference to the inode. We are safe against the second case |
| 2214 | * because if jinode->i_transaction == transaction, commit code |
| 2215 | * cannot touch the transaction because we hold reference to it, |
| 2216 | * and if jinode->i_next_transaction == transaction, commit code |
| 2217 | * will only file the inode where we want it. |
| 2218 | */ |
| 2219 | if (jinode->i_transaction == transaction || |
| 2220 | jinode->i_next_transaction == transaction) |
| 2221 | return 0; |
| 2222 | |
| 2223 | spin_lock(&journal->j_list_lock); |
| 2224 | |
| 2225 | if (jinode->i_transaction == transaction || |
| 2226 | jinode->i_next_transaction == transaction) |
| 2227 | goto done; |
| 2228 | |
Jan Kara | 81be12c | 2011-05-24 11:52:40 -0400 | [diff] [blame] | 2229 | /* |
| 2230 | * We only ever set this variable to 1 so the test is safe. Since |
| 2231 | * t_need_data_flush is likely to be set, we do the test to save some |
| 2232 | * cacheline bouncing |
| 2233 | */ |
| 2234 | if (!transaction->t_need_data_flush) |
| 2235 | transaction->t_need_data_flush = 1; |
Jan Kara | c851ed5 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 2236 | /* On some different transaction's list - should be |
| 2237 | * the committing one */ |
| 2238 | if (jinode->i_transaction) { |
| 2239 | J_ASSERT(jinode->i_next_transaction == NULL); |
| 2240 | J_ASSERT(jinode->i_transaction == |
| 2241 | journal->j_committing_transaction); |
| 2242 | jinode->i_next_transaction = transaction; |
| 2243 | goto done; |
| 2244 | } |
| 2245 | /* Not on any transaction list... */ |
| 2246 | J_ASSERT(!jinode->i_next_transaction); |
| 2247 | jinode->i_transaction = transaction; |
| 2248 | list_add(&jinode->i_list, &transaction->t_inode_list); |
| 2249 | done: |
| 2250 | spin_unlock(&journal->j_list_lock); |
| 2251 | |
| 2252 | return 0; |
| 2253 | } |
| 2254 | |
| 2255 | /* |
Jan Kara | 7f5aa21 | 2009-02-10 11:15:34 -0500 | [diff] [blame] | 2256 | * File truncate and transaction commit interact with each other in a |
| 2257 | * non-trivial way. If a transaction writing data block A is |
| 2258 | * committing, we cannot discard the data by truncate until we have |
| 2259 | * written them. Otherwise if we crashed after the transaction with |
| 2260 | * write has committed but before the transaction with truncate has |
| 2261 | * committed, we could see stale data in block A. This function is a |
| 2262 | * helper to solve this problem. It starts writeout of the truncated |
| 2263 | * part in case it is in the committing transaction. |
| 2264 | * |
| 2265 | * Filesystem code must call this function when inode is journaled in |
| 2266 | * ordered mode before truncation happens and after the inode has been |
| 2267 | * placed on orphan list with the new inode size. The second condition |
| 2268 | * avoids the race that someone writes new data and we start |
| 2269 | * committing the transaction after this function has been called but |
| 2270 | * before a transaction for truncate is started (and furthermore it |
| 2271 | * allows us to optimize the case where the addition to orphan list |
| 2272 | * happens in the same transaction as write --- we don't have to write |
| 2273 | * any data in such case). |
Jan Kara | c851ed5 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 2274 | */ |
Jan Kara | 7f5aa21 | 2009-02-10 11:15:34 -0500 | [diff] [blame] | 2275 | int jbd2_journal_begin_ordered_truncate(journal_t *journal, |
| 2276 | struct jbd2_inode *jinode, |
Jan Kara | c851ed5 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 2277 | loff_t new_size) |
| 2278 | { |
Jan Kara | 7f5aa21 | 2009-02-10 11:15:34 -0500 | [diff] [blame] | 2279 | transaction_t *inode_trans, *commit_trans; |
Jan Kara | c851ed5 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 2280 | int ret = 0; |
| 2281 | |
Jan Kara | 7f5aa21 | 2009-02-10 11:15:34 -0500 | [diff] [blame] | 2282 | /* This is a quick check to avoid locking if not necessary */ |
| 2283 | if (!jinode->i_transaction) |
Jan Kara | c851ed5 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 2284 | goto out; |
Jan Kara | 7f5aa21 | 2009-02-10 11:15:34 -0500 | [diff] [blame] | 2285 | /* Locks are here just to force reading of recent values, it is |
| 2286 | * enough that the transaction was not committing before we started |
| 2287 | * a transaction adding the inode to orphan list */ |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 2288 | read_lock(&journal->j_state_lock); |
Jan Kara | c851ed5 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 2289 | commit_trans = journal->j_committing_transaction; |
Theodore Ts'o | a931da6 | 2010-08-03 21:35:12 -0400 | [diff] [blame] | 2290 | read_unlock(&journal->j_state_lock); |
Jan Kara | 7f5aa21 | 2009-02-10 11:15:34 -0500 | [diff] [blame] | 2291 | spin_lock(&journal->j_list_lock); |
| 2292 | inode_trans = jinode->i_transaction; |
| 2293 | spin_unlock(&journal->j_list_lock); |
| 2294 | if (inode_trans == commit_trans) { |
| 2295 | ret = filemap_fdatawrite_range(jinode->i_vfs_inode->i_mapping, |
Jan Kara | c851ed5 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 2296 | new_size, LLONG_MAX); |
| 2297 | if (ret) |
| 2298 | jbd2_journal_abort(journal, ret); |
| 2299 | } |
| 2300 | out: |
| 2301 | return ret; |
| 2302 | } |