[dm-devel] [PATCH next] Btrfs: fix comparison in __btrfs_map_block()

[Christoph Hellwig]

On Sun, Jul 17, 2016 at 03:51:03PM -0500, Mike Christie wrote:
> > 
> > diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> > index a69203a..6ee1e36 100644
> > --- a/fs/btrfs/volumes.c
> > +++ b/fs/btrfs/volumes.c
> > @@ -5533,7 +5533,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int op,
> >  		}
> >  
> >  	} else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
> > -		if (op == REQ_OP_WRITE || REQ_OP_DISCARD ||
> > +		if (op == REQ_OP_WRITE || op == REQ_OP_DISCARD ||
> >  		    op == REQ_GET_READ_MIRRORS) {
> >  			num_stripes = map->num_stripes;
> >  		} else if (mirror_num) {
> > 
> 
> 
> Shoot. Dumb mistake by me. It is of course correct.

Ad while we're at it we need to fix up that REQ_GET_READ_MIRRORS thing.
Overloading the op localally in a fs is going to create problems sooner
or later as no one touching the generic values and/or the code
mashalling it in different forms knows about it.