Re: [PATCH 1/2] erofs: clean up erofs_iget()

[Xiang Gao]

On 2023/1/13 15:41, Jingbo Xu wrote:
> On 1/13/23 2:52 PM, Gao Xiang wrote:
> > Move inode hash function into inode.c and simplify erofs_iget().
> >
> > Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>
> > ---
> >   fs/erofs/inode.c    | 40 +++++++++++++++++++++-------------------
> >   fs/erofs/internal.h |  9 ---------
> >   2 files changed, 21 insertions(+), 28 deletions(-)
> >
> > diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
> > index d3b8736fa124..57328691582e 100644
> > --- a/fs/erofs/inode.c
> > +++ b/fs/erofs/inode.c
> > @@ -308,47 +308,49 @@ static int erofs_fill_inode(struct inode *inode)
> >   }
> >   
> >   /*
> > - * erofs nid is 64bits, but i_ino is 'unsigned long', therefore
> > - * we should do more for 32-bit platform to find the right inode.
> > + * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
> > + * so that it will fit.
> >    */
> > -static int erofs_ilookup_test_actor(struct inode *inode, void *opaque)
> > +static ino_t erofs_squash_ino(erofs_nid_t nid)
> >   {
> > -	const erofs_nid_t nid = *(erofs_nid_t *)opaque;
> > +	ino_t ino = (ino_t)nid;
> > +
> > +	if (sizeof(ino_t) < sizeof(erofs_nid_t))
> > +		ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;
>
> Shouldn't we do:
>
> 	ino ^= nid >> sizeof(ino_t) * 8
Actually I copied it from fuse, for 64-bit erofs_nid_t it has no difference
though. I will also update it as your suggestion in v2.

Thanks,
Gao Xiang


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