[PATCH v4 4/8] mm/gup: Cleanup next_page handling

From: Peter Xu
Date: Wed Jun 28 2023 - 17:54:33 EST


The only path that doesn't use generic "**pages" handling is the gate vma.
Make it use the same path, meanwhile tune the next_page label upper to
cover "**pages" handling. This prepares for THP handling for "**pages".

Reviewed-by: Lorenzo Stoakes <lstoakes@xxxxxxxxx>
Acked-by: David Hildenbrand <david@xxxxxxxxxx>
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
mm/gup.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/mm/gup.c b/mm/gup.c
index 1e2e23084f3c..5af1be81390b 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1124,7 +1124,7 @@ static long __get_user_pages(struct mm_struct *mm,
if (!vma && in_gate_area(mm, start)) {
ret = get_gate_page(mm, start & PAGE_MASK,
gup_flags, &vma,
- pages ? &pages[i] : NULL);
+ pages ? &page : NULL);
if (ret)
goto out;
ctx.page_mask = 0;
@@ -1194,19 +1194,18 @@ static long __get_user_pages(struct mm_struct *mm,
ret = PTR_ERR(page);
goto out;
}
-
- goto next_page;
} else if (IS_ERR(page)) {
ret = PTR_ERR(page);
goto out;
}
+next_page:
if (pages) {
pages[i] = page;
flush_anon_page(vma, page, start);
flush_dcache_page(page);
ctx.page_mask = 0;
}
-next_page:
+
page_increm = 1 + (~(start >> PAGE_SHIFT) & ctx.page_mask);
if (page_increm > nr_pages)
page_increm = nr_pages;
--
2.41.0