Re: [PATCH v3 04/20] fs: check for writeback errors after syncing out buffers in generic_file_fsync

From: Jan Kara
Date: Mon Apr 24 2017 - 11:46:57 EST


On Mon 24-04-17 09:22:43, Jeff Layton wrote:
> ext2 currently does a test+clear of the AS_EIO flag, which is
> is problematic for some coming changes.
>
> What we really need to do instead is call filemap_check_errors
> in __generic_file_fsync after syncing out the buffers. That
> will be sufficient for this case, and help other callers detect
> these errors properly as well.
>
> With that, we don't need to twiddle it in ext2.
>
> Suggested-by: Jan Kara <jack@xxxxxxx>
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>

Looks good to me. You can add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

Honza
> ---
> fs/ext2/file.c | 2 +-
> fs/libfs.c | 3 ++-
> 2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/fs/ext2/file.c b/fs/ext2/file.c
> index b21891a6bfca..ed00e7ae0ef3 100644
> --- a/fs/ext2/file.c
> +++ b/fs/ext2/file.c
> @@ -177,7 +177,7 @@ int ext2_fsync(struct file *file, loff_t start, loff_t end, int datasync)
> struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
>
> ret = generic_file_fsync(file, start, end, datasync);
> - if (ret == -EIO || test_and_clear_bit(AS_EIO, &mapping->flags)) {
> + if (ret == -EIO) {
> /* We don't really know where the IO error happened... */
> ext2_error(sb, __func__,
> "detected IO error when writing metadata buffers");
> diff --git a/fs/libfs.c b/fs/libfs.c
> index a8b62e5d43a9..12a48ee442d3 100644
> --- a/fs/libfs.c
> +++ b/fs/libfs.c
> @@ -991,7 +991,8 @@ int __generic_file_fsync(struct file *file, loff_t start, loff_t end,
>
> out:
> inode_unlock(inode);
> - return ret;
> + err = filemap_check_errors(inode->i_mapping);
> + return ret ? : err;
> }
> EXPORT_SYMBOL(__generic_file_fsync);
>
> --
> 2.9.3
>
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR