kernel.git/fs/jbd/checkpoint.c, branch linux-3.1.y

jbd: Use WRITE_SYNC in journal checkpoint.

2011-06-27T22:06:41Z

In journal checkpoint, we write the buffer and wait for its finish. But in cfq, the async queue has a very low priority, and in our test, if there are too many sync queues and every queue is filled up with requests, and the process will hang waiting for the log space. So this patch tries to use WRITE_SYNC in __flush_batch so that the request will be moved into sync queue and handled by cfq timely. We also use the new plug, sot that all the WRITE_SYNC requests can be given as a whole when we unplug it. Reported-by: Robin Dong Signed-off-by: Tao Ma Signed-off-by: Jan Kara

jbd: Fix oops in journal_remove_journal_head()

2011-06-27T09:44:37Z

journal_remove_journal_head() can oops when trying to access journal_head returned by bh2jh(). This is caused for example by the following race: TASK1 TASK2 journal_commit_transaction() ... processing t_forget list __journal_refile_buffer(jh); if (!jh->b_transaction) { jbd_unlock_bh_state(bh); journal_try_to_free_buffers() journal_grab_journal_head(bh) jbd_lock_bh_state(bh) __journal_try_to_free_buffer() journal_put_journal_head(jh) journal_remove_journal_head(bh); journal_put_journal_head() in TASK2 sees that b_jcount == 0 and buffer is not part of any transaction and thus frees journal_head before TASK1 gets to doing so. Note that even buffer_head can be released by try_to_free_buffers() after journal_put_journal_head() which adds even larger opportunity for oops (but I didn't see this happen in reality). Fix the problem by making transactions hold their own journal_head reference (in b_jcount). That way we don't have to remove journal_head explicitely via journal_remove_journal_head() and instead just remove journal_head when b_jcount drops to zero. The result of this is that [__]journal_refile_buffer(), [__]journal_unfile_buffer(), and __journal_remove_checkpoint() can free journal_head which needs modification of a few callers. Also we have to be careful because once journal_head is removed, buffer_head might be freed as well. So we have to get our own buffer_head reference where it matters. Signed-off-by: Jan Kara

jbd: Add fixed tracepoints

2011-06-25T15:29:51Z

This commit adds fixed tracepoint for jbd. It has been based on fixed tracepoints for jbd2, however there are missing those for collecting statistics, since I think that it will require more intrusive patch so I should have its own commit, if someone decide that it is needed. Also there are new tracepoints in __journal_drop_transaction() and journal_update_superblock(). The list of jbd tracepoints: jbd_checkpoint jbd_start_commit jbd_commit_locking jbd_commit_flushing jbd_commit_logging jbd_drop_transaction jbd_end_commit jbd_do_submit_data jbd_cleanup_journal_tail jbd_update_superblock_end Signed-off-by: Lukas Czerner Cc: Jan Kara Signed-off-by: Jan Kara

jbd: Convert atomic_inc() to get_bh()

2010-10-27T23:30:05Z

Convert atomic_inc(&bh->b_count) to get_bh(bh) for consistency. Signed-off-by: Namhyung Kim Signed-off-by: Jan Kara

remove SWRITE* I/O types

2010-08-18T05:09:01Z

These flags aren't real I/O types, but tell ll_rw_block to always lock the buffer instead of giving up on a failed trylock. Instead add a new write_dirty_buffer helper that implements this semantic and use it from the existing SWRITE* callers. Note that the ll_rw_block code had a bug where it didn't promote WRITE_SYNC_PLUG properly, which this patch fixes. In the ufs code clean up the helper that used to call ll_rw_block to mirror sync_dirty_buffer, which is the function it implements for compound buffers. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro

jbd: Journal block numbers can ever be only 32-bit use unsigned int for them

2009-09-16T15:44:10Z

It does not make sense to store block number for journal as unsigned long since they can be only 32-bit (because of on-disk format limitation). So change in-memory structures and variables to use unsigned int instead. Signed-off-by: Jan Kara

jbd: don't give up looking for space so easily in __log_wait_for_space

2008-11-07T03:37:59Z

Commit be07c4ed introducd a regression because it assumed that if there were no transactions ready to be checkpointed, that no progress could be made on making space available in the journal, and so the journal should be aborted. This assumption is false; it could be the case that simply calling cleanup_journal_tail() will recover the necessary space, or, for small journals, the currently committing transaction could be responsible for chewing up the required space in the log, so we need to wait for the currently committing transaction to finish before trying to force a checkpoint operation. This patch fixes the bug reported by Meelis Roos at: http://bugzilla.kernel.org/show_bug.cgi?id=11937 Signed-off-by: "Theodore Ts'o" Cc: Duane Griffin Cc: Toshiyuki Okajima

jbd: abort instead of waiting for nonexistent transactions

2008-10-23T15:55:02Z

The __log_wait_for_space function sits in a loop checkpointing transactions until there is sufficient space free in the journal. However, if there are no transactions to be processed (e.g. because the free space calculation is wrong due to a corrupted filesystem) it will never progress. Check for space being required when no transactions are outstanding and abort the journal instead of endlessly looping. This patch fixes the bug reported by Sami Liedes at: http://bugzilla.kernel.org/show_bug.cgi?id=10976 Signed-off-by: Duane Griffin Tested-by: Sami Liedes Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

jbd: test BH_Write_EIO to detect errors on metadata buffers

2008-10-23T15:55:02Z

__try_to_free_cp_buf(), __process_buffer(), and __wait_cp_io() test BH_Uptodate flag to detect write I/O errors on metadata buffers. But by commit 95450f5a7e53d5752ce1a0d0b8282e10fe745ae0 "ext3: don't read inode block if the buffer has a write error"(*), BH_Uptodate flag can be set to inode buffers with BH_Write_EIO in order to avoid reading old inode data. So now, we have to test BH_Write_EIO flag of checkpointing inode buffers instead of BH_Uptodate. This patch does it. Signed-off-by: Hidehiro Kawai Acked-by: Jan Kara Acked-by: Eric Sandeen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

jbd: fix error handling for checkpoint io

2008-10-23T15:55:01Z

When a checkpointing IO fails, current JBD code doesn't check the error and continue journaling. This means latest metadata can be lost from both the journal and filesystem. This patch leaves the failed metadata blocks in the journal space and aborts journaling in the case of log_do_checkpoint(). To achieve this, we need to do: 1. don't remove the failed buffer from the checkpoint list where in the case of __try_to_free_cp_buf() because it may be released or overwritten by a later transaction 2. log_do_checkpoint() is the last chance, remove the failed buffer from the checkpoint list and abort the journal 3. when checkpointing fails, don't update the journal super block to prevent the journaled contents from being cleaned. For safety, don't update j_tail and j_tail_sequence either 4. when checkpointing fails, notify this error to the ext3 layer so that ext3 don't clear the needs_recovery flag, otherwise the journaled contents are ignored and cleaned in the recovery phase 5. if the recovery fails, keep the needs_recovery flag 6. prevent cleanup_journal_tail() from being called between __journal_drop_transaction() and journal_abort() (a race issue between journal_flush() and __log_wait_for_space() Signed-off-by: Hidehiro Kawai Acked-by: Jan Kara Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds