Re: [PATCH] f2fs: add new wraper function for reading inline data

[Shawn Lin]

On 2016/2/19 15:35, Chao Yu wrote:

Hi Shawn,

-----Original Message-----
From: Shawn Lin [mailto:shawn....@rock-chips.com]
Sent: Friday, February 19, 2016 10:50 AM
To: Jaegeuk Kim; Changman Lee
Cc: Chao Yu; linux-f2fs-de...@lists.sourceforge.net; 
linux-kernel@vger.kernel.org; Shawn Lin
Subject: [PATCH] f2fs: add new wraper function for reading inline data

This patch add __read_inline_data which will no check
PageUptodate and page->index. This can be reused by
f2fs_convert_inline_page to reduce the redundant code
copied from read_inline_data.

Signed-off-by: Shawn Lin <shawn....@rock-chips.com>
---

  fs/f2fs/inline.c | 26 ++++++++++++--------------
  1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index d27347e..39eeff1 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -42,15 +42,11 @@ bool f2fs_may_inline_dentry(struct inode *inode)
        return true;
  }

-void read_inline_data(struct page *page, struct page *ipage)
+static inline void __read_inline_data(struct page *page,
+                                     struct page *ipage)
  {
        void *src_addr, *dst_addr;

-       if (PageUptodate(page))
-               return;
-
-       f2fs_bug_on(F2FS_P_SB(page), page->index);
-
        zero_user_segment(page, MAX_INLINE_DATA, PAGE_CACHE_SIZE);

        /* Copy the whole inline data block */
@@ -61,6 +57,15 @@ void read_inline_data(struct page *page, struct page *ipage)
        kunmap_atomic(dst_addr);
        SetPageUptodate(page);
  }
+void read_inline_data(struct page *page, struct page *ipage)
+{
+       if (PageUptodate(page))
+               return;
+
+       f2fs_bug_on(F2FS_P_SB(page), page->index);
+
+       __read_inline_data(page, ipage);
+}

  bool truncate_inline_inode(struct page *ipage, u64 from)
  {
@@ -128,15 +133,8 @@ int f2fs_convert_inline_page(struct dnode_of_data *dn, 
struct page *page)
        if (PageUptodate(page))
                goto no_update;

Seems we can remove above check and below 'no_update' tag completely
if we use read_inline_data here.

So what about using read_inline_data to clean up codes in
f2fs_convert_inline_page?

yep, it does make sense. I will respin v2 to the list later.
Thanks for sharing your thought.

Thanks,

-       zero_user_segment(page, MAX_INLINE_DATA, PAGE_CACHE_SIZE);
+       __read_inline_data(page, dn->inode_page);

-       /* Copy the whole inline data block */
-       src_addr = inline_data_addr(dn->inode_page);
-       dst_addr = kmap_atomic(page);
-       memcpy(dst_addr, src_addr, MAX_INLINE_DATA);
-       flush_dcache_page(page);
-       kunmap_atomic(dst_addr);
-       SetPageUptodate(page);
  no_update:
        set_page_dirty(page);

--
2.3.7

--
Best Regards
Shawn Lin