| Message ID | 20181231194836.3761-2-tytso@mit.edu |
|---|---|
| State | New |
| Headers | show |
| Series | [1/3] ext4: avoid kernel warning when writing the superblock to a dead device | expand |
On Mon 31-12-18 14:48:35, Theodore Ts'o wrote: > In no-journal mode, we previously used __generic_file_fsync() in > no-journal mode. This triggers a lockdep warning, and in addition, > it's not safe to depend on the inode writeback mechanism in the case > ext4. We can solve both problems by calling ext4_write_inode() > directly. > > Signed-off-by: Theodore Ts'o <tytso@mit.edu> > Cc: stable@kernel.org > --- > fs/ext4/fsync.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c > index 26a7fe5c4fd3..87a7ff00ef62 100644 > --- a/fs/ext4/fsync.c > +++ b/fs/ext4/fsync.c > @@ -116,8 +116,16 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync) > goto out; > } > > + ret = file_write_and_wait_range(file, start, end); > + if (ret) > + return ret; > + > if (!journal) { > - ret = __generic_file_fsync(file, start, end, datasync); > + struct writeback_control wbc = { > + .sync_mode = WB_SYNC_ALL > + }; > + > + ret = ext4_write_inode(inode, &wbc); Going through some older email... How come this is safe Ted? ext4_write_inode() will not write out metadata buffers associated with the inode (unlike __generic_file_fsync() which calls sync_mapping_buffers()). So you probably need to call sync_mapping_buffers() before calling ext4_write_inode() here? Honza > @@ -125,9 +133,6 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync) > goto out; > } > > - ret = file_write_and_wait_range(file, start, end); > - if (ret) > - return ret; > /* > * data=writeback,ordered: > * The caller's filemap_fdatawrite()/wait will sync the data. > -- > 2.19.1 >
diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c index 26a7fe5c4fd3..87a7ff00ef62 100644 --- a/fs/ext4/fsync.c +++ b/fs/ext4/fsync.c @@ -116,8 +116,16 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync) goto out; } + ret = file_write_and_wait_range(file, start, end); + if (ret) + return ret; + if (!journal) { - ret = __generic_file_fsync(file, start, end, datasync); + struct writeback_control wbc = { + .sync_mode = WB_SYNC_ALL + }; + + ret = ext4_write_inode(inode, &wbc); if (!ret) ret = ext4_sync_parent(inode); if (test_opt(inode->i_sb, BARRIER)) @@ -125,9 +133,6 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync) goto out; } - ret = file_write_and_wait_range(file, start, end); - if (ret) - return ret; /* * data=writeback,ordered: * The caller's filemap_fdatawrite()/wait will sync the data.
In no-journal mode, we previously used __generic_file_fsync() in no-journal mode. This triggers a lockdep warning, and in addition, it's not safe to depend on the inode writeback mechanism in the case ext4. We can solve both problems by calling ext4_write_inode() directly. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org --- fs/ext4/fsync.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)