Hi Jaegeuk, > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk@xxxxxxxxxx] > Sent: Wednesday, January 06, 2016 1:49 AM > To: Chao Yu > Cc: linux-kernel@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; > linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx > Subject: Re: [f2fs-dev] [PATCH 1/3] f2fs: check the page status filled from disk > > Hi Chao, > > On Tue, Jan 05, 2016 at 05:31:51PM +0800, Chao Yu wrote: > > Hi Jaegeuk, > > > > > -----Original Message----- > > > From: Jaegeuk Kim [mailto:jaegeuk@xxxxxxxxxx] > > > Sent: Sunday, January 03, 2016 9:26 AM > > > To: linux-kernel@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; > > > linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx > > > Cc: Jaegeuk Kim > > > Subject: [f2fs-dev] [PATCH 1/3] f2fs: check the page status filled from disk > > > > > > After reading a page, we need to check whether there is any error. > > > > > > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> > > > --- > > > fs/f2fs/data.c | 8 ++++++++ > > > 1 file changed, 8 insertions(+) > > > > > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > > > index 89a978c..11b2111 100644 > > > --- a/fs/f2fs/data.c > > > +++ b/fs/f2fs/data.c > > > @@ -448,6 +448,14 @@ repeat: > > > > > > /* wait for read completion */ > > > lock_page(page); > > > + if (unlikely(!PageUptodate(page))) { > > > + f2fs_put_page(page, 1); > > > + return ERR_PTR(-EIO); > > > > There is a convention in get_new_data_page, anyway we should release ipage > > if there is any error occurs, but I think it will be ok to return directly > > since it seems impossible the new dentry page has its real block address. > > Makes sense, but definitely ipage should be put. :) Alright. :) > > > > > To avoid any bug here or wrong usage, how about add bug_on as following patch? > > > > >From d92f0f34493b27ef28da67c446d552ce721b5d6f Mon Sep 17 00:00:00 2001 > > From: Chao Yu <chao2.yu@xxxxxxxxxxx> > > Date: Tue, 5 Jan 2016 15:28:56 +0800 > > Subject: [PATCH] f2fs: add f2fs_bug_on in get_new_data_page > > > > In get_new_data_page, locked inode page should not be hold before > > get_read_data_page, this patch adds f2fs_bug_on to detect this > > condition. > > > > Signed-off-by: Chao Yu <chao2.yu@xxxxxxxxxxx> > > --- > > fs/f2fs/data.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > > index 48f0bd3..2c5e3f6 100644 > > --- a/fs/f2fs/data.c > > +++ b/fs/f2fs/data.c > > @@ -440,6 +440,8 @@ repeat: > > zero_user_segment(page, 0, PAGE_CACHE_SIZE); > > SetPageUptodate(page); > > } else { > > + f2fs_bug_on(F2FS_I_SB(inode), ipage); > > + > > f2fs_put_page(page, 1); > > > > page = get_read_data_page(inode, index, READ_SYNC, true); > > -- > > 2.6.3 > > > > > > > + } > > > + if (unlikely(page->mapping != mapping)) { > > > + f2fs_put_page(page, 1); > > > + goto repeat; > > > + } > > > > How about use get_lock_data_page to avoid duplicated code? > > Agreed. > > How about this? > > From fef77fb244a706491e8e4c46cb245e99e22003c3 Mon Sep 17 00:00:00 2001 > From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> > Date: Fri, 1 Jan 2016 22:03:47 -0800 > Subject: [PATCH] f2fs: check the page status filled from disk > > After reading a page, we need to check whether there is any error. > > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> > --- > fs/f2fs/data.c | 14 +++++++++----- > 1 file changed, 9 insertions(+), 5 deletions(-) > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 89a978c..89d633a 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -442,12 +442,16 @@ repeat: > } else { > f2fs_put_page(page, 1); > > - page = get_read_data_page(inode, index, READ_SYNC, true); > - if (IS_ERR(page)) > - goto repeat; > + f2fs_bug_on(F2FS_I_SB(inode), ipage); > > - /* wait for read completion */ > - lock_page(page); > + page = get_lock_data_page(inode, index, true); > + if (IS_ERR(page)) { > + if (PTR_ERR(page) == -EIO) { > + f2fs_put_page(ipage, 1); > + return page; > + } > + goto repeat; Seems if get_lock_data_page always return -EFAULT, we may run into an infinite loop. IMO, it's not a bad thing to tolerate other error more than EIO returned from get_lock_data_page. How about return directly when error is returned? And add a bug_on for ENOENT which seems not impossible here? Thanks, > + } > } > got_it: > if (new_i_size && i_size_read(inode) < > -- > 2.6.3 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
