FROMGIT: maple_tree: clear up index and last setting in single entry tree

When there is a single entry tree (range of 0-0 pointing to an entry),
then ensure the limit is either 0-0 or 1-oo, depending on where the user
walks.  Ensure the correct node setting as well; either MAS_ROOT or
MAS_NONE.

Link: https://lkml.kernel.org/r/20230518145544.1722059-33-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

(cherry picked from commit c0b1bdd9011ef34b654fe62f2607bff0eb1ef0a8
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm mm-unstable)

Bug: 274059236
Change-Id: I22a41c01e525fde88774b509cd5cbc60f56f6dc5
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
This commit is contained in:
Liam R. Howlett 2023-05-18 10:55:41 -04:00 committed by Suren Baghdasaryan
parent 9288f53a31
commit 86d9de0898

View file

@ -5050,24 +5050,25 @@ void *mas_walk(struct ma_state *mas)
{
void *entry;
if (mas_is_none(mas) || mas_is_paused(mas) || mas_is_ptr(mas))
mas->node = MAS_START;
retry:
entry = mas_state_walk(mas);
if (mas_is_start(mas))
if (mas_is_start(mas)) {
goto retry;
if (mas_is_ptr(mas)) {
if (!mas->index) {
mas->last = 0;
} else {
mas->index = 1;
mas->last = ULONG_MAX;
}
return entry;
}
if (mas_is_none(mas)) {
} else if (mas_is_none(mas)) {
mas->index = 0;
mas->last = ULONG_MAX;
} else if (mas_is_ptr(mas)) {
if (!mas->index) {
mas->last = 0;
return entry;
}
mas->index = 1;
mas->last = ULONG_MAX;
mas->node = MAS_NONE;
return NULL;
}
return entry;