| Message ID | 20200426214925.10970-2-guoqing.jiang@cloud.ionos.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Introduce set/clear_fs_page_private to cleanup code | expand |
Why not attach_page_private and clear_page_private as that conveys the use case a little better? > +static inline void *set_fs_page_private(struct page *page, void *data) > +{ > + get_page(page); > + set_page_private(page, (unsigned long)data); > + SetPagePrivate(page); > + > + return data; > +} > + > +static inline void *clear_fs_page_private(struct page *page) > +{ > + void *data = (void *)page_private(page); > + > + if (!PagePrivate(page)) > + return NULL; > + ClearPagePrivate(page); > + set_page_private(page, 0); > + put_page(page); > + > + return data; > +} Can you add kerneldoc comments describing them, including why we take the refernces? Also what is the point of the return value of set_fs_page_private?
Hi Christoph, On 4/27/20 7:52 AM, Christoph Hellwig wrote: > Why not attach_page_private and clear_page_private as that conveys > the use case a little better? Yes, thanks for the good suggestion. Will rename them if no one else has new idea ... >> +static inline void *set_fs_page_private(struct page *page, void *data) >> +{ >> + get_page(page); >> + set_page_private(page, (unsigned long)data); >> + SetPagePrivate(page); >> + >> + return data; >> +} >> + >> +static inline void *clear_fs_page_private(struct page *page) >> +{ >> + void *data = (void *)page_private(page); >> + >> + if (!PagePrivate(page)) >> + return NULL; >> + ClearPagePrivate(page); >> + set_page_private(page, 0); >> + put_page(page); >> + >> + return data; >> +} > Can you add kerneldoc comments describing them, including why we > take the refernces? Ok, will do. > Also what is the point of the return value of set_fs_page_private? In this way, iomap_page_create can just return the function, but you don't like this way as you replied, will change the return value to "void". Thanks, Guoqing
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index a8f7bd8ea1c6..2a165ea647fe 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -205,6 +205,28 @@ static inline int page_cache_add_speculative(struct page *page, int count) return __page_cache_add_speculative(page, count); } +static inline void *set_fs_page_private(struct page *page, void *data) +{ + get_page(page); + set_page_private(page, (unsigned long)data); + SetPagePrivate(page); + + return data; +} + +static inline void *clear_fs_page_private(struct page *page) +{ + void *data = (void *)page_private(page); + + if (!PagePrivate(page)) + return NULL; + ClearPagePrivate(page); + set_page_private(page, 0); + put_page(page); + + return data; +} + #ifdef CONFIG_NUMA extern struct page *__page_cache_alloc(gfp_t gfp); #else
The logic in attach_page_buffers and __clear_page_buffers are quite paired, but 1. they are located in different files. 2. attach_page_buffers is implemented in buffer_head.h, so it could be used by other files. But __clear_page_buffers is static function in buffer.c and other potential users can't call the function, md-bitmap even copied the function. So, introduce the new set/clear_fs_page_private to replace them since they are mostly used in fs layer. With the new pair of function, we will remove the usage of attach_page_buffers and __clear_page_buffers in next patches. Suggested-by: Matthew Wilcox <willy@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Cc: William Kucharski <william.kucharski@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Yang Shi <yang.shi@linux.alibaba.com> Cc: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> --- include/linux/pagemap.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)