[RFC PATCH 4/8] null_blk: use memcpy_page() in copy_from_nullb()

Chaitanya Kulkarni
2021-02-07T19:07:06Z

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
---
drivers/block/null_blk/main.c | 16 +++++-----------
1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index c9b6db82b07c..1c0e1a295e90 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1042,7 +1042,6 @@ static int copy_from_nullb(struct nullb *nullb, struct page *dest,
size_t temp, count = 0;
unsigned int offset;
struct nullb_page *t_page;
- void *dst, *src;

while (count < n) {
temp = min_t(size_t, nullb->dev->blocksize, n - count);
@@ -1051,16 +1050,11 @@ static int copy_from_nullb(struct nullb *nullb, struct page *dest,
t_page = null_lookup_page(nullb, sector, false,
!null_cache_active(nullb));

- dst = kmap_atomic(dest);
- if (!t_page) {
- memset(dst + off + count, 0, temp);
- goto next;
- }
- src = kmap_atomic(t_page->page);
- memcpy(dst + off + count, src + offset, temp);
- kunmap_atomic(src);
-next:
- kunmap_atomic(dst);
+ if (t_page)
+ memcpy_page(dest, off + count, t_page->page, offset,
+ temp);
+ else
+ zero_user(dest, off + count, temp);

count += temp;
sector += temp >> SECTOR_SHIFT;
--
2.22.1