> -----Original Message-----
> From: Jiri Pirko [mailto:j...@resnulli.us]
> Sent: Tuesday, August 29, 2017 3:57 PM
> To: Chris Mi <chr...@mellanox.com>
> Cc: Hannes Frederic Sowa <han...@stressinduktion.org>;
> netdev@vger.kernel.org; j...@mojatatu.com; xiyou.wangc...@gmail.com;
> da...@davemloft.net; mawil...@microsoft.com
> Subject: Re: [patch net-next 1/3] idr: Add new APIs to support unsigned long
>
> Tue, Aug 29, 2017 at 09:34:47AM CEST, chr...@mellanox.com wrote:
> >Hi,
> >
> >> -----Original Message-----
> >> From: Hannes Frederic Sowa [mailto:han...@stressinduktion.org]
> >> Sent: Tuesday, August 29, 2017 3:14 PM
> >> To: Chris Mi <chr...@mellanox.com>
> >> Cc: netdev@vger.kernel.org; j...@mojatatu.com;
> >> xiyou.wangc...@gmail.com; j...@resnulli.us; da...@davemloft.net;
> >> mawil...@microsoft.com
> >> Subject: Re: [patch net-next 1/3] idr: Add new APIs to support
> >> unsigned long
> >>
> >> Hello,
> >>
> >> Chris Mi <chr...@mellanox.com> writes:
> >>
> >> > The following new APIs are added:
> >> >
> >> > int idr_alloc_ext(struct idr *idr, void *ptr, unsigned long *index,
> >> > unsigned long start, unsigned long end, gfp_t
> >> > gfp); static inline void *idr_remove_ext(struct idr *idr, unsigned
> >> > long id); static inline void *idr_find_ext(const struct idr *idr,
> >> > unsigned long id); void *idr_replace_ext(struct idr *idr, void
> >> > *ptr, unsigned long id); void *idr_get_next_ext(struct idr *idr,
> >> > unsigned long *nextid);
> >> >
> >> > Signed-off-by: Chris Mi <chr...@mellanox.com>
> >> > Signed-off-by: Jiri Pirko <j...@mellanox.com>
> >> > ---
> >> > include/linux/idr.h | 16 ++++++++++
> >> > include/linux/radix-tree.h | 3 ++
> >> > lib/idr.c | 56 +++++++++++++++++++++++++++++++++++
> >> > lib/radix-tree.c | 73
> >> ++++++++++++++++++++++++++++++++++++++++++++++
> >> > 4 files changed, 148 insertions(+)
> >> >
> >>
> >> [...]
> >>
> >> > +int idr_alloc_ext(struct idr *idr, void *ptr, unsigned long *index,
> >> > + unsigned long start, unsigned long end, gfp_t gfp) {
> >> > + void __rcu **slot;
> >> > + struct radix_tree_iter iter;
> >> > +
> >> > + if (WARN_ON_ONCE(radix_tree_is_internal_node(ptr)))
> >> > + return -EINVAL;
> >> > +
> >> > + radix_tree_iter_init(&iter, start);
> >> > + slot = idr_get_free_ext(&idr->idr_rt, &iter, gfp, end);
> >> > + if (IS_ERR(slot))
> >> > + return PTR_ERR(slot);
> >> > +
> >> > + radix_tree_iter_replace(&idr->idr_rt, &iter, slot, ptr);
> >> > + radix_tree_iter_tag_clear(&idr->idr_rt, &iter, IDR_FREE);
> >> > +
> >> > + if (index)
> >> > + *index = iter.index;
> >> > + return 0;
> >> > +}
> >> > +EXPORT_SYMBOL_GPL(idr_alloc_ext);
> >>
> >> Can you express idr_alloc in terms of idr_alloc_ext? Same for most of
> >> the other functions (it seems that signed int was used as return
> >> value to indicate error cases, thus it should be easy to map those).
> >In idr_alloc(), we have the following check:
> >
> > if (WARN_ON_ONCE(start < 0))
> > return -EINVAL;
> >
> >But in idr_alloc_ext(), since we are using unsigned long, we needn't such
> check.
>
> You can just check and call idr_alloc_ext then to do the actual work.
OK, will fix it.
