[PATCH v2 01/12] get rid of unlikely() on page_copy_sane() calls

From: Al Viro
Date: Thu Oct 27 2022 - 22:35:00 EST


Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
lib/iov_iter.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index c3ca28ca68a6..e9a8fc9ee8ee 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -703,17 +703,16 @@ static inline bool page_copy_sane(struct page *page, size_t offset, size_t n)
head = compound_head(page);
v += (page - head) << PAGE_SHIFT;

- if (likely(n <= v && v <= (page_size(head))))
- return true;
- WARN_ON(1);
- return false;
+ if (WARN_ON(n > v || v > page_size(head)))
+ return false;
+ return true;
}

size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes,
struct iov_iter *i)
{
size_t res = 0;
- if (unlikely(!page_copy_sane(page, offset, bytes)))
+ if (!page_copy_sane(page, offset, bytes))
return 0;
if (unlikely(iov_iter_is_pipe(i)))
return copy_page_to_iter_pipe(page, offset, bytes, i);
@@ -808,7 +807,7 @@ size_t copy_page_from_iter_atomic(struct page *page, unsigned offset, size_t byt
struct iov_iter *i)
{
char *kaddr = kmap_atomic(page), *p = kaddr + offset;
- if (unlikely(!page_copy_sane(page, offset, bytes))) {
+ if (!page_copy_sane(page, offset, bytes)) {
kunmap_atomic(kaddr);
return 0;
}
--
2.30.2