linux.git/fs/jbd2/commit.c, branch v5.10

jbd2: add todo for a fast commit performance optimization

2020-11-07T04:01:03+00:00

Fast commit performance can be optimized if commit thread doesn't wait
for ongoing fast commits to complete until the transaction enters
T_FLUSH state. Document this optimization.

Suggested-by: Jan Kara 
Signed-off-by: Harshad Shirwadkar 
Link: https://lore.kernel.org/r/20201106035911.1942128-11-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o

jbd2: rename j_maxlen to j_total_len and add jbd2_journal_max_txn_bufs

2020-11-07T04:01:02+00:00

The on-disk superblock field sb->s_maxlen represents the total size of
the journal including the fast commit area and is no more the max
number of blocks available for a transaction. The maximum number of
blocks available to a transaction is reduced by the number of fast
commit blocks. So, this patch renames j_maxlen to j_total_len to
better represent its intent. Also, it adds a function to calculate max
number of bufs available for a transaction.

Suggested-by: Jan Kara 
Signed-off-by: Harshad Shirwadkar 
Link: https://lore.kernel.org/r/20201106035911.1942128-6-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o

jbd2: add fast commit machinery

2020-10-22T03:22:37+00:00

This functions adds necessary APIs needed in JBD2 layer for fast
commits.

Signed-off-by: Harshad Shirwadkar 
Link: https://lore.kernel.org/r/20201015203802.3597742-5-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o

jbd2, ext4, ocfs2: introduce/use journal callbacks j_submit|finish_inode_data_buffers()

2020-10-18T14:37:15+00:00

Introduce journal callbacks to allow different behaviors
for an inode in journal_submit|finish_inode_data_buffers().

The existing users of the current behavior (ext4, ocfs2)
are adapted to use the previously exported functions
that implement the current behavior.

Users are callers of jbd2_journal_inode_ranged_write|wait(),
which adds the inode to the transaction's inode list with
the JI_WRITE|WAIT_DATA flags. Only ext4 and ocfs2 in-tree.

Both CONFIG_EXT4_FS and CONFIG_OCSFS2_FS select CONFIG_JBD2,
which builds fs/jbd2/commit.c and journal.c that define and
export the functions, so we can call directly in ext4/ocfs2.

Signed-off-by: Mauricio Faria de Oliveira 
Suggested-by: Jan Kara 
Reviewed-by: Jan Kara 
Reviewed-by: Andreas Dilger 
Link: https://lore.kernel.org/r/20201006004841.600488-3-mfo@canonical.com
Signed-off-by: Theodore Ts'o

jbd2: introduce/export functions jbd2_journal_submit|finish_inode_data_buffers()

2020-10-18T14:37:15+00:00

Export functions that implement the current behavior done
for an inode in journal_submit|finish_inode_data_buffers().

No functional change.

Signed-off-by: Mauricio Faria de Oliveira 
Suggested-by: Jan Kara 
Reviewed-by: Jan Kara 
Reviewed-by: Andreas Dilger 
Link: https://lore.kernel.org/r/20201006004841.600488-2-mfo@canonical.com
Signed-off-by: Theodore Ts'o

block: remove the error_sector argument to blkdev_issue_flush

2020-05-22T14:45:46+00:00

The argument isn't used by any caller, and drivers don't fill out
bi_sector for flush requests either.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

jbd2: improve comments about freeing data buffers whose page mapping is NULL

2020-03-06T01:25:05+00:00

Improve comments in jbd2_journal_commit_transaction() to describe why
we don't need to clear the buffer_mapped bit for freeing file mapping
buffers whose page mapping is NULL.

Link: https://lore.kernel.org/r/20200217112706.20085-1-yi.zhang@huawei.com
Fixes: c96dceeabf76 ("jbd2: do not clear the BH_Mapped flag when forgetting a metadata buffer")
Suggested-by: Jan Kara 
Reviewed-by: Jan Kara 
Signed-off-by: zhangyi (F) 
Signed-off-by: Theodore Ts'o

jbd2: do not clear the BH_Mapped flag when forgetting a metadata buffer

2020-02-13T17:06:28+00:00

Commit 904cdbd41d74 ("jbd2: clear dirty flag when revoking a buffer from
an older transaction") set the BH_Freed flag when forgetting a metadata
buffer which belongs to the committing transaction, it indicate the
committing process clear dirty bits when it is done with the buffer. But
it also clear the BH_Mapped flag at the same time, which may trigger
below NULL pointer oops when block_size < PAGE_SIZE.

rmdir 1             kjournald2                 mkdir 2
                    jbd2_journal_commit_transaction
		    commit transaction N
jbd2_journal_forget
set_buffer_freed(bh1)
                    jbd2_journal_commit_transaction
                     commit transaction N+1
                     ...
                     clear_buffer_mapped(bh1)
                                               ext4_getblk(bh2 ummapped)
                                               ...
                                               grow_dev_page
                                                init_page_buffers
                                                 bh1->b_private=NULL
                                                 bh2->b_private=NULL
                     jbd2_journal_put_journal_head(jh1)
                      __journal_remove_journal_head(hb1)
		       jh1 is NULL and trigger oops

*) Dir entry block bh1 and bh2 belongs to one page, and the bh2 has
   already been unmapped.

For the metadata buffer we forgetting, we should always keep the mapped
flag and clear the dirty flags is enough, so this patch pick out the
these buffers and keep their BH_Mapped flag.

Link: https://lore.kernel.org/r/20200213063821.30455-3-yi.zhang@huawei.com
Fixes: 904cdbd41d74 ("jbd2: clear dirty flag when revoking a buffer from an older transaction")
Reviewed-by: Jan Kara 
Signed-off-by: zhangyi (F) 
Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org

jbd2: move the clearing of b_modified flag to the journal_unmap_buffer()

2020-02-13T17:06:17+00:00

There is no need to delay the clearing of b_modified flag to the
transaction committing time when unmapping the journalled buffer, so
just move it to the journal_unmap_buffer().

Link: https://lore.kernel.org/r/20200213063821.30455-2-yi.zhang@huawei.com
Reviewed-by: Jan Kara 
Signed-off-by: zhangyi (F) 
Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org

jbd2: switch to use jbd2_journal_abort() when failed to submit the commit record

2020-01-25T07:58:46+00:00

We invoke jbd2_journal_abort() to abort the journal and record errno
in the jbd2 superblock when committing journal transaction besides the
failure on submitting the commit record. But there is no need for the
case and we can also invoke jbd2_journal_abort() instead of
__jbd2_journal_abort_hard().

Fixes: 818d276ceb83a ("ext4: Add the journal checksum feature")
Signed-off-by: zhangyi (F) 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20191204124614.45424-2-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o