From 28961998f858114e51d2ae862065b858afcfa2b2 Mon Sep 17 00:00:00 2001 From: Ira Weiny Date: Tue, 4 May 2021 18:40:03 -0700 Subject: [PATCH] iov_iter: lift memzero_page() to highmem.h Patch series "btrfs: Convert kmap/memset/kunmap to memzero_user()". Lifting memzero_user(), convert it to kmap_local_page() and then use it in btrfs. This patch (of 3): memzero_page() can replace the kmap/memset/kunmap pattern in other places in the code. While zero_user() has the same interface it is not the same call and its use should be limited and some of those calls may be better converted from zero_user() to memzero_page().[1] But that is not addressed in this series. Lift memzero_page() to highmem. [1] https://lore.kernel.org/lkml/CAHk-=wijdojzo56FzYqE5TOYw2Vws7ik3LEMGj9SPQaJJ+Z73Q@mail.gmail.com/ Link: https://lkml.kernel.org/r/20210309212137.2610186-1-ira.weiny@intel.com Link: https://lkml.kernel.org/r/20210309212137.2610186-2-ira.weiny@intel.com Signed-off-by: Ira Weiny Cc: Alexander Viro Cc: David Sterba Cc: Chris Mason Cc: Josef Bacik Cc: Chaitanya Kulkarni Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/highmem.h | 7 +++++++ lib/iov_iter.c | 8 +------- 2 files changed, 8 insertions(+), 7 deletions(-) diff --git a/include/linux/highmem.h b/include/linux/highmem.h index 44170f312ae7..832b49b50c7b 100644 --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -332,4 +332,11 @@ static inline void memcpy_to_page(struct page *page, size_t offset, kunmap_local(to); } +static inline 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); +} + #endif /* _LINUX_HIGHMEM_H */ diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 61228a6c69f8..c701b7a187f2 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -5,6 +5,7 @@ #include #include #include +#include #include #include #include @@ -507,13 +508,6 @@ 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; -- 2.39.5