[PATCH] maple_tree: document that "last" in mtree_insert_range() is inclusive

[Liam R. Howlett]

On 26/05/07 06:44AM, Alice Ryhl wrote:
> On Wed, May 06, 2026 at 10:52:18AM -0400, Steven Rostedt wrote:
> > From: Steven Rostedt <rostedt at goodmis.org>
> > 
> > The kernel doc of mtree_insert_range() does not state if the address
> > represented by the "last" parameter is inclusive or exclusive. This can
> > lead to bugs by code that assumes it is exclusive. Explicitly state that
> > the parameter is inclusive, and add '[' and ']' around the word "end" to
> > also stress this point.
> > 
> > Signed-off-by: Steven Rostedt <rostedt at goodmis.org>
> 
> Reviewed-by: Alice Ryhl <aliceryhl at google.com>
> 
> >  lib/maple_tree.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> > index 60ae5e6fc1ee..dc9591218446 100644
> > --- a/lib/maple_tree.c
> > +++ b/lib/maple_tree.c
> > @@ -5730,10 +5730,12 @@ EXPORT_SYMBOL(mtree_store);
> >   * mtree_insert_range() - Insert an entry at a given range if there is no value.
> >   * @mt: The maple tree
> >   * @first: The start of the range
> > - * @last: The end of the range
> > + * @last: The [end] of the range
> >   * @entry: The entry to store
> >   * @gfp: The GFP_FLAGS to use for allocations.
> >   *
> > + * Note that @last is inclusive. That is, @last = @first + length - 1;
> 
> How about writing it like this?
> 
> * @first: The start of the range
> * @last: The end of the range (inclusive)


I like this.

I think the range should be identified in the initial statement.
Something like this:

mtree_insert_range() - Insert an entry from [first, last] if there isn't
an entry within that range.

> 
> Alice
> 
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