Re: [PATCH v11 10/25] xfs: Refactor xfs_attr_rmtval_remove

Darrick J. Wong
2020-07-22T00:24:51Z

On Tue, Jul 21, 2020 at 04:31:18PM -0700, Darrick J. Wong wrote:
> On Mon, Jul 20, 2020 at 05:15:51PM -0700, Allison Collins wrote:
> > Refactor xfs_attr_rmtval_remove to add helper function
> > __xfs_attr_rmtval_remove. We will use this later when we introduce
> > delayed attributes. This function will eventually replace
> > xfs_attr_rmtval_remove
> >
> > Signed-off-by: Allison Collins <allison.henderson@oracle.com>
> > Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
> > Reviewed-by: Brian Foster <bfoster@redhat.com>
> > ---
> > fs/xfs/libxfs/xfs_attr_remote.c | 46 ++++++++++++++++++++++++++++++++---------
> > fs/xfs/libxfs/xfs_attr_remote.h | 1 +
> > 2 files changed, 37 insertions(+), 10 deletions(-)
> >
> > diff --git a/fs/xfs/libxfs/xfs_attr_remote.c b/fs/xfs/libxfs/xfs_attr_remote.c
> > index 4d51969..9b4c173 100644
> > --- a/fs/xfs/libxfs/xfs_attr_remote.c
> > +++ b/fs/xfs/libxfs/xfs_attr_remote.c
> > @@ -681,7 +681,7 @@ xfs_attr_rmtval_remove(
> > xfs_dablk_t lblkno;
> > int blkcnt;
> > int error = 0;
> > - int done = 0;
> > + int retval = 0;
> >
> > trace_xfs_attr_rmtval_remove(args);
> >
> > @@ -693,14 +693,10 @@ xfs_attr_rmtval_remove(
> > */
> > lblkno = args->rmtblkno;
> > blkcnt = args->rmtblkcnt;
>
> Er... I think these local variables can go away here, right?
>
> --D
>
> > - while (!done) {
> > - error = xfs_bunmapi(args->trans, args->dp, lblkno, blkcnt,
> > - XFS_BMAPI_ATTRFORK, 1, &done);
> > - if (error)
> > - return error;
> > - error = xfs_defer_finish(&args->trans);
> > - if (error)
> > - return error;
> > + do {
> > + retval = __xfs_attr_rmtval_remove(args);
> > + if (retval && retval != EAGAIN)

Also this has to be -EAGAIN. Amazingly, nothing in fstests blew up on
this.

--D

> > + return retval;
> >
> > /*
> > * Close out trans and start the next one in the chain.
> > @@ -708,6 +704,36 @@ xfs_attr_rmtval_remove(
> > error = xfs_trans_roll_inode(&args->trans, args->dp);
> > if (error)
> > return error;
> > - }
> > + } while (retval == -EAGAIN);
> > +
> > return 0;
> > }
> > +
> > +/*
> > + * Remove the value associated with an attribute by deleting the out-of-line
> > + * buffer that it is stored on. Returns EAGAIN for the caller to refresh the
> > + * transaction and re-call the function
> > + */
> > +int
> > +__xfs_attr_rmtval_remove(
> > + struct xfs_da_args *args)
> > +{
> > + int error, done;
> > +
> > + /*
> > + * Unmap value blocks for this attr.
> > + */
> > + error = xfs_bunmapi(args->trans, args->dp, args->rmtblkno,
> > + args->rmtblkcnt, XFS_BMAPI_ATTRFORK, 1, &done);
> > + if (error)
> > + return error;
> > +
> > + error = xfs_defer_finish(&args->trans);
> > + if (error)
> > + return error;
> > +
> > + if (!done)
> > + return -EAGAIN;
> > +
> > + return error;
> > +}
> > diff --git a/fs/xfs/libxfs/xfs_attr_remote.h b/fs/xfs/libxfs/xfs_attr_remote.h
> > index 3616e88..9eee615 100644
> > --- a/fs/xfs/libxfs/xfs_attr_remote.h
> > +++ b/fs/xfs/libxfs/xfs_attr_remote.h
> > @@ -14,4 +14,5 @@ int xfs_attr_rmtval_remove(struct xfs_da_args *args);
> > int xfs_attr_rmtval_stale(struct xfs_inode *ip, struct xfs_bmbt_irec *map,
> > xfs_buf_flags_t incore_flags);
> > int xfs_attr_rmtval_invalidate(struct xfs_da_args *args);
> > +int __xfs_attr_rmtval_remove(struct xfs_da_args *args);
> > #endif /* __XFS_ATTR_REMOTE_H__ */
> > --
> > 2.7.4
> >