On Wed, Nov 01, 2023 at 06:43:06PM +0100, Jan Kara wrote:
> Convert bcachefs to use bdev_open_by_path() and pass the handle around.
>
> CC: Kent Overstreet <kent.overstreet@xxxxxxxxx>
> CC: Brian Foster <bfoster@xxxxxxxxxx>
> CC: linux-bcachefs@xxxxxxxxxxxxxxx
> Signed-off-by: Jan Kara <jack@xxxxxxx>
> ---
> fs/bcachefs/super-io.c | 19 ++++++++++---------
> fs/bcachefs/super_types.h | 1 +
> 2 files changed, 11 insertions(+), 9 deletions(-)
>
> diff --git a/fs/bcachefs/super-io.c b/fs/bcachefs/super-io.c
> index 332d41e1c0a3..01a32c41a540 100644
> --- a/fs/bcachefs/super-io.c
> +++ b/fs/bcachefs/super-io.c
...
> @@ -685,21 +685,22 @@ int bch2_read_super(const char *path, struct bch_opts *opts,
> if (!opt_get(*opts, nochanges))
> sb->mode |= BLK_OPEN_WRITE;
>
> - sb->bdev = blkdev_get_by_path(path, sb->mode, sb->holder, &bch2_sb_handle_bdev_ops);
> - if (IS_ERR(sb->bdev) &&
> - PTR_ERR(sb->bdev) == -EACCES &&
> + sb->bdev_handle = bdev_open_by_path(path, sb->mode, sb->holder, &bch2_sb_handle_bdev_ops);
> + if (IS_ERR(sb->bdev_handle) &&
> + PTR_ERR(sb->bdev_handle) == -EACCES &&
> opt_get(*opts, read_only)) {
> sb->mode &= ~BLK_OPEN_WRITE;
>
> - sb->bdev = blkdev_get_by_path(path, sb->mode, sb->holder, &bch2_sb_handle_bdev_ops);
> - if (!IS_ERR(sb->bdev))
> + sb->bdev_handle = bdev_open_by_path(path, sb->mode, sb->holder, &bch2_sb_handle_bdev_ops);
> + if (!IS_ERR(sb->bdev_handle))
> opt_set(*opts, nochanges, true);
> }
>
> - if (IS_ERR(sb->bdev)) {
> - ret = PTR_ERR(sb->bdev);
> + if (IS_ERR(sb->bdev_handle)) {
> + ret = PTR_ERR(sb->bdev_handle);
> goto out;
> }
> + sb->bdev = sb->bdev_handle->bdev;
>
> ret = bch2_sb_realloc(sb, 0);
> if (ret) {
Hi Jan,
This all seems reasonable to me, but should bcachefs use sb_open_mode()
somewhere in here to involve use of the restrict writes flag in the
first place? It looks like bcachefs sort of open codes bits of
mount_bdev() so it isn't clear the flag would be used anywhere...
Brian
> diff --git a/fs/bcachefs/super_types.h b/fs/bcachefs/super_types.h
> index 78d6138db62d..b77d8897c9fa 100644
> --- a/fs/bcachefs/super_types.h
> +++ b/fs/bcachefs/super_types.h
> @@ -4,6 +4,7 @@
>
> struct bch_sb_handle {
> struct bch_sb *sb;
> + struct bdev_handle *bdev_handle;
> struct block_device *bdev;
> struct bio *bio;
> void *holder;
> --
> 2.35.3
>
