2021-02-10 08:36:47

by Ira Weiny

[permalink] [raw]
Subject: [PATCH V2 5/8] iov_iter: Remove memzero_page() in favor of zero_user()

From: Ira Weiny <[email protected]>

zero_user() is already defined with the same interface and contains the
same code pattern as memzero_page(). Remove memzero_page() and use the
already defined common function zero_user()

To: Alexander Viro <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Signed-off-by: Ira Weiny <[email protected]>

---
New for V2
---
lib/iov_iter.c | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 9889e9903cdf..aa0d03b33a1e 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -5,6 +5,7 @@
#include <linux/fault-inject-usercopy.h>
#include <linux/uio.h>
#include <linux/pagemap.h>
+#include <linux/highmem.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/splice.h>
@@ -466,13 +467,6 @@ void iov_iter_init(struct iov_iter *i, unsigned int direction,
}
EXPORT_SYMBOL(iov_iter_init);

-static void memzero_page(struct page *page, size_t offset, size_t len)
-{
- char *addr = kmap_atomic(page);
- memset(addr + offset, 0, len);
- kunmap_atomic(addr);
-}
-
static inline bool allocated(struct pipe_buffer *buf)
{
return buf->ops == &default_pipe_buf_ops;
@@ -950,7 +944,7 @@ static size_t pipe_zero(size_t bytes, struct iov_iter *i)

do {
size_t chunk = min_t(size_t, n, PAGE_SIZE - off);
- memzero_page(pipe->bufs[i_head & p_mask].page, off, chunk);
+ zero_user(pipe->bufs[i_head & p_mask].page, off, chunk);
i->head = i_head;
i->iov_offset = off + chunk;
n -= chunk;
@@ -967,7 +961,7 @@ size_t iov_iter_zero(size_t bytes, struct iov_iter *i)
return pipe_zero(bytes, i);
iterate_and_advance(i, bytes, v,
clear_user(v.iov_base, v.iov_len),
- memzero_page(v.bv_page, v.bv_offset, v.bv_len),
+ zero_user(v.bv_page, v.bv_offset, v.bv_len),
memset(v.iov_base, 0, v.iov_len)
)

--
2.28.0.rc0.12.gb6a658bd00c9


2021-02-10 13:01:48

by Christoph Hellwig

[permalink] [raw]
Subject: Re: [PATCH V2 5/8] iov_iter: Remove memzero_page() in favor of zero_user()

On Tue, Feb 09, 2021 at 10:22:18PM -0800, [email protected] wrote:
> From: Ira Weiny <[email protected]>
>
> zero_user() is already defined with the same interface and contains the
> same code pattern as memzero_page(). Remove memzero_page() and use the
> already defined common function zero_user()

Looks good,

Reviewed-by: Christoph Hellwig <[email protected]>