* Peng Zhang <zhangpeng.00@xxxxxxxxxxxxx> [230517 04:58]:
> Use mas_empty_area{_rev}() to refactor mtree_alloc_{range,rrange}()
>
> Signed-off-by: Peng Zhang <zhangpeng.00@xxxxxxxxxxxxx>
> ---
> lib/maple_tree.c | 63 ++++++++++++++++++++++++------------------------
> 1 file changed, 32 insertions(+), 31 deletions(-)
>
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index 4eb220008f72..e1820e90f167 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -6493,32 +6493,31 @@ int mtree_alloc_range(struct maple_tree *mt, unsigned long *startp,
> {
> int ret = 0;
>
> - MA_STATE(mas, mt, min, min);
> + MA_STATE(mas, mt, 0, 0);
> if (!mt_is_alloc(mt))
> return -EINVAL;
>
> if (WARN_ON_ONCE(mt_is_reserved(entry)))
> return -EINVAL;
>
> - if (min > max)
> - return -EINVAL;
> -
> - if (max < size)
> - return -EINVAL;
> -
> - if (!size)
> - return -EINVAL;
> -
> mtree_lock(mt);
> retry:
> - mas.offset = 0;
> - mas.index = min;
> - mas.last = max - size + 1;
> - ret = mas_alloc(&mas, entry, size, startp);
> - if (mas_nomem(&mas, gfp))
> - goto retry;
> -
> + ret = mas_empty_area(&mas, min, max, size);
> + if (!ret) {
> + mas_insert(&mas, entry);
> + /*
> + * mas_nomem() may release the lock, causing the allocated area
> + * to be unavailable, so try to allocate a free area again.
> + */
> + if (mas_nomem(&mas, gfp))
> + goto retry;
> + }
> mtree_unlock(mt);
> + if (!ret) {
Checking for a mas_is_err() should probably be outside if (!ret)
statement. If mas_insert() returns something besides ENOMEM, we will
not detect the error. I'm not sure if this is possible today since this
should never return an -EEXISTS, but having it this way doesn't add much
to the overhead.
> + if (mas_is_err(&mas))
> + return xa_err(mas.node);
> + *startp = mas.index;
> + }
> return ret;
> }
> EXPORT_SYMBOL(mtree_alloc_range);
> @@ -6529,29 +6528,31 @@ int mtree_alloc_rrange(struct maple_tree *mt, unsigned long *startp,
> {
> int ret = 0;
>
> - MA_STATE(mas, mt, min, max - size + 1);
> + MA_STATE(mas, mt, 0, 0);
> if (!mt_is_alloc(mt))
> return -EINVAL;
>
> if (WARN_ON_ONCE(mt_is_reserved(entry)))
> return -EINVAL;
>
> - if (min > max)
> - return -EINVAL;
> -
> - if (max < size - 1)
> - return -EINVAL;
> -
> - if (!size)
> - return -EINVAL;
> -
> mtree_lock(mt);
> retry:
> - ret = mas_rev_alloc(&mas, min, max, entry, size, startp);
> - if (mas_nomem(&mas, gfp))
> - goto retry;
> -
> + ret = mas_empty_area_rev(&mas, min, max, size);
> + if (!ret) {
> + mas_insert(&mas, entry);
> + /*
> + * mas_nomem() may release the lock, causing the allocated area
> + * to be unavailable, so try to allocate a free area again.
> + */
> + if (mas_nomem(&mas, gfp))
> + goto retry;
> + }
> mtree_unlock(mt);
> + if (!ret) {
Same here.
> + if (mas_is_err(&mas))
> + return xa_err(mas.node);
> + *startp = mas.index;
> + }
> return ret;
> }
> EXPORT_SYMBOL(mtree_alloc_rrange);
> --
> 2.20.1
>
