Re: [patch net-next 1/3] idr: Add new APIs to support unsigned long

Tue, Aug 29, 2017 at 09:14:04AM CEST, hannes@stressinduktion.org wrote:

Hello,

Chris Mi [off-list ref] writes:

quoted

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 <redacted>
Signed-off-by: Jiri Pirko <redacted>
---
 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(+)

[...]

quoted

+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).

Agreed. Same for free function.

[...]

Thanks,
Hannes