On Thu, Nov 02, 2023 at 10:55:50AM +0100, Jan Kara wrote: > Hi Brian, > > On Wed 01-11-23 15:01:22, Brian Foster wrote: > > 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 <[email protected]> > > > CC: Brian Foster <[email protected]> > > > CC: [email protected] > > > Signed-off-by: Jan Kara <[email protected]> > > > --- > > > 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) { > > > > 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... > > Yes, so AFAICS bcachefs will not get the write restriction from the changes > in the generic code. Using sb_open_mode() in bcachefs would fix that but > given the 'noexcl' and 'nochanges' mount options it will not be completely > seamless anyway. I guess once the generic changes are in, bcachefs can > decide how exactly it wants to set the BLK_OPEN_RESTRICT_WRITES flag. Or if > you already have an opinion, we can just add the patch to this series. >
Yep, makes sense, and I agree with Kent this should be a separate patch anyways. Just wanted to make sure I wasn't missing something or otherwise it was known that bcachefs needs a bit more work to turn this on... thanks. Brian > Honza > -- > Jan Kara <[email protected]> > SUSE Labs, CR >
