From 9c305126dd9775b8768aaadb240cffd29da3130e Mon Sep 17 00:00:00 2001 From: Jakob Koschel Date: Thu, 31 Mar 2022 23:39:34 +0200 Subject: FROMLIST: staging: android: ashmem: remove usage of list iterator after the loop body In preparation to limit the scope of a list iterator to the list traversal loop, use a dedicated pointer to point to the found element [1]. Before, the code implicitly used the head when no element was found when using &pos->list. Since the new variable is only set if an element was found, the head needs to be used explicitly if the variable is NULL. Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1] Signed-off-by: Jakob Koschel Signed-off-by: Greg Kroah-Hartman [sw0312.kim: cherry-pick commit 4f49a861af66 of https://android.googlesource.com/kernel/common/+/refs/heads/android15-6.6 to support waydroid on tizen] Signed-off-by: Seung-Woo Kim Change-Id: Ifaf19dd876a513a1952fac448079d664aebdf604 --- drivers/staging/android/ashmem.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c index ddbde3f8430e..a1e245827cf6 100644 --- a/drivers/staging/android/ashmem.c +++ b/drivers/staging/android/ashmem.c @@ -703,30 +703,33 @@ static int ashmem_pin(struct ashmem_area *asma, size_t pgstart, size_t pgend, static int ashmem_unpin(struct ashmem_area *asma, size_t pgstart, size_t pgend, struct ashmem_range **new_range) { - struct ashmem_range *range, *next; + struct ashmem_range *range = NULL, *iter, *next; unsigned int purged = ASHMEM_NOT_PURGED; restart: - list_for_each_entry_safe(range, next, &asma->unpinned_list, unpinned) { + list_for_each_entry_safe(iter, next, &asma->unpinned_list, unpinned) { /* short circuit: this is our insertion point */ - if (range_before_page(range, pgstart)) + if (range_before_page(iter, pgstart)) { + range = iter; break; + } /* * The user can ask us to unpin pages that are already entirely * or partially pinned. We handle those two cases here. */ - if (page_range_subsumed_by_range(range, pgstart, pgend)) + if (page_range_subsumed_by_range(iter, pgstart, pgend)) return 0; - if (page_range_in_range(range, pgstart, pgend)) { - pgstart = min(range->pgstart, pgstart); - pgend = max(range->pgend, pgend); - purged |= range->purged; - range_del(range); + if (page_range_in_range(iter, pgstart, pgend)) { + pgstart = min(iter->pgstart, pgstart); + pgend = max(iter->pgend, pgend); + purged |= iter->purged; + range_del(iter); goto restart; } } + range = list_prepare_entry(range, &asma->unpinned_list, unpinned); range_alloc(asma, range, purged, pgstart, pgend, new_range); return 0; } -- cgit v1.2.3