Re: [PATCH 1/4] mm/highmem: Lift memcpy_[to|from]_page to core

[Ira Weiny]

On Sun, Feb 07, 2021 at 01:46:47AM +0000, Chaitanya Kulkarni wrote:
> On 2/5/21 18:35, ira.weiny@xxxxxxxxx wrote:
> > +static inline void memmove_page(struct page *dst_page, size_t dst_off,
> > +			       struct page *src_page, size_t src_off,
> > +			       size_t len)
> > +{
> > +	char *dst = kmap_local_page(dst_page);
> > +	char *src = kmap_local_page(src_page);
> > +
> > +	BUG_ON(dst_off + len > PAGE_SIZE || src_off + len > PAGE_SIZE);
> > +	memmove(dst + dst_off, src + src_off, len);
> > +	kunmap_local(src);
> > +	kunmap_local(dst);
> > +}
> > +
> > +static inline void memcpy_from_page(char *to, struct page *page, size_t offset, size_t len)
> How about following ?
> static inline void memcpy_from_page(char *to, struct page *page, size_t
> offset,
>                                     size_t len)  

It is an easy change and It is up to Andrew.  But I thought we were making the
line length limit longer now.

Ira

> > +{
> > +	char *from = kmap_local_page(page);
> > +
> > +	BUG_ON(offset + len > PAGE_SIZE);
> > +	memcpy(to, from + offset, len);
> > +	kunmap_local(from);
> > +}
> > +
> > +static inline void memcpy_to_page(struct page *page, size_t offset, const char *from, size_t len)
> How about following ?
> static inline void memcpy_to_page(struct page *page, size_t offset,
>                                   const char *from, size_t len)
> > +{
> > +	char *to = kmap_local_page(page);
> > +
> > +	BUG_ON(offset + len > PAGE_SIZE);
> > +	memcpy(to + offset, from, len);
> > +	kunmap_local(to);
> > +}
> > +
> > +static inline void memset_page(struct page *page, size_t offset, int val, size_t len)
> How about following ?
> static inline void memset_page(struct page *page, size_t offset, int val,
>                                size_t len)  
> > +{
> > +	char *addr = kmap_local_page(page);
> > +
> > +	BUG_ON(offset + len > PAGE_SIZE);
> > +	memset(addr + offset, val, len);
> > +	kunmap_local(addr);
> > +}
> > +