From mboxrd@z Thu Jan 1 00:00:00 1970 From: Changman Lee Subject: Re: [PATCH 1/3] f2fs: call flush_dcache_page when the page was updated Date: Thu, 20 Nov 2014 15:04:10 +0900 Message-ID: <20141120060410.GB3117@lcm> References: <1416436510-6251-1-git-send-email-jaegeuk@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1XrKs4-0006m6-MO for linux-f2fs-devel@lists.sourceforge.net; Thu, 20 Nov 2014 06:05:36 +0000 Received: from mailout2.samsung.com ([203.254.224.25]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-MD5:128) (Exim 4.76) id 1XrKs2-0000ip-D9 for linux-f2fs-devel@lists.sourceforge.net; Thu, 20 Nov 2014 06:05:36 +0000 Received: from epcpsbgr3.samsung.com (u143.gpu120.samsung.co.kr [203.254.230.143]) by mailout2.samsung.com (Oracle Communications Messaging Server 7u4-24.01 (7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0NFB00JUHQ925E70@mailout2.samsung.com> for linux-f2fs-devel@lists.sourceforge.net; Thu, 20 Nov 2014 15:05:26 +0900 (KST) Content-disposition: inline In-reply-to: <1416436510-6251-1-git-send-email-jaegeuk@kernel.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: Jaegeuk Kim Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Hi Jaegeuk, We should call flush_dcache_page before kunmap because the purpose of the cache flush is to address aliasing problem related to virtual address. On Wed, Nov 19, 2014 at 02:35:08PM -0800, Jaegeuk Kim wrote: > Whenever f2fs updates mapped pages, it needs to call flush_dcache_page. > > Signed-off-by: Jaegeuk Kim > --- > fs/f2fs/dir.c | 7 ++++++- > fs/f2fs/inline.c | 4 +++- > 2 files changed, 9 insertions(+), 2 deletions(-) > > diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c > index 5a49995..312fbfc 100644 > --- a/fs/f2fs/dir.c > +++ b/fs/f2fs/dir.c > @@ -287,8 +287,10 @@ void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de, > f2fs_wait_on_page_writeback(page, type); > de->ino = cpu_to_le32(inode->i_ino); > set_de_type(de, inode); > - if (!f2fs_has_inline_dentry(dir)) > + if (!f2fs_has_inline_dentry(dir)) { > kunmap(page); > + flush_dcache_page(page); > + } > set_page_dirty(page); > dir->i_mtime = dir->i_ctime = CURRENT_TIME; > mark_inode_dirty(dir); > @@ -366,6 +368,7 @@ static int make_empty_dir(struct inode *inode, > do_make_empty_dir(inode, parent, &d); > > kunmap_atomic(dentry_blk); > + flush_dcache_page(dentry_page); > > set_page_dirty(dentry_page); > f2fs_put_page(dentry_page, 1); > @@ -579,6 +582,7 @@ fail: > clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR); > } > kunmap(dentry_page); > + flush_dcache_page(dentry_page); > f2fs_put_page(dentry_page, 1); > return err; > } > @@ -661,6 +665,7 @@ void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page, > NR_DENTRY_IN_BLOCK, > 0); > kunmap(page); /* kunmap - pair of f2fs_find_entry */ > + flush_dcache_page(page); > set_page_dirty(page); > > dir->i_ctime = dir->i_mtime = CURRENT_TIME; > diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c > index f26fb87..8b7cc51 100644 > --- a/fs/f2fs/inline.c > +++ b/fs/f2fs/inline.c > @@ -45,8 +45,8 @@ void read_inline_data(struct page *page, struct page *ipage) > src_addr = inline_data_addr(ipage); > dst_addr = kmap_atomic(page); > memcpy(dst_addr, src_addr, MAX_INLINE_DATA); > - flush_dcache_page(page); > kunmap_atomic(dst_addr); > + flush_dcache_page(page); > SetPageUptodate(page); > } > > @@ -107,6 +107,7 @@ int f2fs_convert_inline_page(struct dnode_of_data *dn, struct page *page) > dst_addr = kmap_atomic(page); > memcpy(dst_addr, src_addr, MAX_INLINE_DATA); > kunmap_atomic(dst_addr); > + flush_dcache_page(page); > SetPageUptodate(page); > no_update: > /* write data page to try to make data consistent */ > @@ -358,6 +359,7 @@ static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage, > NR_INLINE_DENTRY * F2FS_SLOT_LEN); > > kunmap_atomic(dentry_blk); > + flush_dcache_page(page); > SetPageUptodate(page); > set_page_dirty(page); > > -- > 2.1.1 > > > ------------------------------------------------------------------------------ > Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server > from Actuate! Instantly Supercharge Your Business Reports and Dashboards > with Interactivity, Sharing, Native Excel Exports, App Integration & more > Get technology previously reserved for billion-dollar corporations, FREE > http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk