[PATCH] f2fs: fix to truncate inline data past EOF

[PATCH] f2fs: fix to truncate inline data past EOF

[Chao Yu]

Previously if inode is with inline data, we will try to invalid partial inline
data in page #0 when we truncate size of inode in truncate_partial_data_page().
And then we set page #0 to dirty, after this we can synchronize inode page with
page #0 at ->writepage().

But sometimes we will fail to operate page #0 in truncate_partial_data_page()
due to below reason:
a) if offset is zero, we will skip setting page #0 to dirty.
b) if page #0 is not uptodate, we will fail to update it as it has no mapping
data.

So with following operations, we will meet recent data which should be
truncated.

1.write inline data to file
2.sync first data page to inode page
3.truncate file size to 0
4.truncate file size to max_inline_size
5.echo 1 > /proc/sys/vm/drop_caches
6.read file --> meet original inline data which is remained in inode page.

This patch renames truncate_inline_data() to truncate_inline_inode() for code
readability, then intruduces new truncate_inline_data() and use it to truncate
inline data in page #0 and inode page in truncate_partial_data_page() for
fixing.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
---
 fs/f2fs/f2fs.h   |  1 +
 fs/f2fs/file.c   | 13 ++++++++-----
 fs/f2fs/inline.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++-----
 3 files changed, 61 insertions(+), 10 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 511d6cd..55dbbe7 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
  */
 bool f2fs_may_inline(struct inode *);
 void read_inline_data(struct page *, struct page *);
+int truncate_inline_data(struct inode *, u64 from);
 int f2fs_read_inline_data(struct inode *, struct page *);
 int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
 int f2fs_convert_inline_inode(struct inode *);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index f1341c7..6c4443e 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -461,6 +461,9 @@ static int truncate_partial_data_page(struct inode *inode, u64 from)
 	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
 	struct page *page;
 
+	if (f2fs_has_inline_data(inode))
+		return 0;
+
 	if (!offset)
 		return 0;
 
@@ -497,14 +500,14 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
 	if (lock)
 		f2fs_lock_op(sbi);
 
-	ipage = get_node_page(sbi, inode->i_ino);
-	if (IS_ERR(ipage)) {
-		err = PTR_ERR(ipage);
+	if (f2fs_has_inline_data(inode)) {
+		err = truncate_inline_data(inode, from);
 		goto out;
 	}
 
-	if (f2fs_has_inline_data(inode)) {
-		f2fs_put_page(ipage, 1);
+	ipage = get_node_page(sbi, inode->i_ino);
+	if (IS_ERR(ipage)) {
+		err = PTR_ERR(ipage);
 		goto out;
 	}
 
diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index 4ba9732..a8189c92 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -50,10 +50,57 @@ void read_inline_data(struct page *page, struct page *ipage)
 	SetPageUptodate(page);
 }
 
-static void truncate_inline_data(struct page *ipage)
+static void truncate_inline_inode(struct page *ipage, u64 from)
 {
+	void *addr = inline_data_addr(ipage);
+
 	f2fs_wait_on_page_writeback(ipage, NODE);
-	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
+	memset(addr + from, 0, MAX_INLINE_DATA - from);
+}
+
+int truncate_inline_data(struct inode *inode, u64 from)
+{
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	struct page *page, *ipage;
+	void *addr;
+	int err = 0;
+
+	/*
+	 * we should never truncate inline data past max inline data size,
+	 * because we always convert inline inode to normal one before
+	 * truncating real data if new size is past max inline data size.
+	 */
+	f2fs_bug_on(sbi, from > MAX_INLINE_DATA);
+
+	if (from == MAX_INLINE_DATA)
+		return 0;
+
+	page = grab_cache_page(inode->i_mapping, 0);
+	if (!page)
+		return -ENOMEM;
+
+	ipage = get_node_page(sbi, inode->i_ino);
+	if (IS_ERR(ipage)) {
+		err = PTR_ERR(ipage);
+		goto out;
+	}
+
+	if (!f2fs_has_inline_data(inode)) {
+		f2fs_put_page(ipage, 1);
+		goto out;
+	}
+
+	truncate_inline_inode(ipage, from);
+	set_page_dirty(ipage);
+
+	read_inline_data(page, ipage);
+	f2fs_put_page(ipage, 1);
+
+	addr = inline_data_addr(page);
+	memset(addr + from, 0, MAX_INLINE_DATA - from);
+out:
+	f2fs_put_page(page, 1);
+	return err;
 }
 
 int f2fs_read_inline_data(struct inode *inode, struct page *page)
@@ -131,7 +178,7 @@ no_update:
 	set_inode_flag(F2FS_I(dn->inode), FI_APPEND_WRITE);
 
 	/* clear inline data and flag after data writeback */
-	truncate_inline_data(dn->inode_page);
+	truncate_inline_inode(dn->inode_page, 0);
 clear_out:
 	stat_dec_inline_inode(dn->inode);
 	f2fs_clear_inline_inode(dn->inode);
@@ -245,7 +292,7 @@ process_inline:
 	if (f2fs_has_inline_data(inode)) {
 		ipage = get_node_page(sbi, inode->i_ino);
 		f2fs_bug_on(sbi, IS_ERR(ipage));
-		truncate_inline_data(ipage);
+		truncate_inline_inode(ipage, 0);
 		f2fs_clear_inline_inode(inode);
 		update_inode(inode, ipage);
 		f2fs_put_page(ipage, 1);
@@ -363,7 +410,7 @@ static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
 	set_page_dirty(page);
 
 	/* clear inline dir and flag after data writeback */
-	truncate_inline_data(ipage);
+	truncate_inline_inode(ipage, 0);
 
 	stat_dec_inline_dir(dir);
 	clear_inode_flag(F2FS_I(dir), FI_INLINE_DENTRY);
-- 
2.3.1

Re: [PATCH] f2fs: fix to truncate inline data past EOF

[Jaegeuk Kim]

Hi Chao,

On Thu, Mar 05, 2015 at 05:41:32PM +0800, Chao Yu wrote:
> Previously if inode is with inline data, we will try to invalid partial inline
> data in page #0 when we truncate size of inode in truncate_partial_data_page().
> And then we set page #0 to dirty, after this we can synchronize inode page with
> page #0 at ->writepage().
> 
> But sometimes we will fail to operate page #0 in truncate_partial_data_page()
> due to below reason:
> a) if offset is zero, we will skip setting page #0 to dirty.
> b) if page #0 is not uptodate, we will fail to update it as it has no mapping
> data.
> 
> So with following operations, we will meet recent data which should be
> truncated.
> 
> 1.write inline data to file
> 2.sync first data page to inode page
> 3.truncate file size to 0
> 4.truncate file size to max_inline_size
> 5.echo 1 > /proc/sys/vm/drop_caches
> 6.read file --> meet original inline data which is remained in inode page.
> 
> This patch renames truncate_inline_data() to truncate_inline_inode() for code
> readability, then intruduces new truncate_inline_data() and use it to truncate
> inline data in page #0 and inode page in truncate_partial_data_page() for
> fixing.
> 
> Signed-off-by: Chao Yu <chao2.yu@samsung.com>
> ---
>  fs/f2fs/f2fs.h   |  1 +
>  fs/f2fs/file.c   | 13 ++++++++-----
>  fs/f2fs/inline.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++-----
>  3 files changed, 61 insertions(+), 10 deletions(-)
> 
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 511d6cd..55dbbe7 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
>   */
>  bool f2fs_may_inline(struct inode *);
>  void read_inline_data(struct page *, struct page *);
> +int truncate_inline_data(struct inode *, u64 from);
>  int f2fs_read_inline_data(struct inode *, struct page *);
>  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
>  int f2fs_convert_inline_inode(struct inode *);
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index f1341c7..6c4443e 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -461,6 +461,9 @@ static int truncate_partial_data_page(struct inode *inode, u64 from)
>  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
>  	struct page *page;
>  
> +	if (f2fs_has_inline_data(inode))
> +		return 0;
> +
>  	if (!offset)
>  		return 0;
>  
> @@ -497,14 +500,14 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
>  	if (lock)
>  		f2fs_lock_op(sbi);
>  
> -	ipage = get_node_page(sbi, inode->i_ino);
> -	if (IS_ERR(ipage)) {
> -		err = PTR_ERR(ipage);
> +	if (f2fs_has_inline_data(inode)) {
> +		err = truncate_inline_data(inode, from);
>  		goto out;
>  	}
>  
> -	if (f2fs_has_inline_data(inode)) {
> -		f2fs_put_page(ipage, 1);
> +	ipage = get_node_page(sbi, inode->i_ino);
> +	if (IS_ERR(ipage)) {
> +		err = PTR_ERR(ipage);
>  		goto out;
>  	}
>  
> diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
> index 4ba9732..a8189c92 100644
> --- a/fs/f2fs/inline.c
> +++ b/fs/f2fs/inline.c
> @@ -50,10 +50,57 @@ void read_inline_data(struct page *page, struct page *ipage)
>  	SetPageUptodate(page);
>  }
>  
> -static void truncate_inline_data(struct page *ipage)
> +static void truncate_inline_inode(struct page *ipage, u64 from)
>  {
> +	void *addr = inline_data_addr(ipage);
> +
>  	f2fs_wait_on_page_writeback(ipage, NODE);
> -	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
> +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> +}
> +
> +int truncate_inline_data(struct inode *inode, u64 from)
> +{
> +	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> +	struct page *page, *ipage;
> +	void *addr;
> +	int err = 0;
> +
> +	/*
> +	 * we should never truncate inline data past max inline data size,
> +	 * because we always convert inline inode to normal one before
> +	 * truncating real data if new size is past max inline data size.
> +	 */
> +	f2fs_bug_on(sbi, from > MAX_INLINE_DATA);
> +
> +	if (from == MAX_INLINE_DATA)
> +		return 0;
> +
> +	page = grab_cache_page(inode->i_mapping, 0);
> +	if (!page)
> +		return -ENOMEM;

Do we need to grab and read #0 page?
How about checking its cached page after on-disk truncation?

1. page = get_node_page()
2. check_inline
3. truncate_inline_inode
4. f2fs_put_page(ipage)

5. truncate_partial_data_page(inode, from, force)
	if (!offset && !force)
 		return 0;

> +
> +	ipage = get_node_page(sbi, inode->i_ino);
> +	if (IS_ERR(ipage)) {
> +		err = PTR_ERR(ipage);
> +		goto out;
> +	}
> +
> +	if (!f2fs_has_inline_data(inode)) {
> +		f2fs_put_page(ipage, 1);
> +		goto out;
> +	}
> +
> +	truncate_inline_inode(ipage, from);
> +	set_page_dirty(ipage);
> +
> +	read_inline_data(page, ipage);
> +	f2fs_put_page(ipage, 1);
> +
> +	addr = inline_data_addr(page);
> +	memset(addr + from, 0, MAX_INLINE_DATA - from);

It needs to do likewise truncate_partial_data_page.

Thanks,

> +out:
> +	f2fs_put_page(page, 1);
> +	return err;
>  }
>  
>  int f2fs_read_inline_data(struct inode *inode, struct page *page)
> @@ -131,7 +178,7 @@ no_update:
>  	set_inode_flag(F2FS_I(dn->inode), FI_APPEND_WRITE);
>  
>  	/* clear inline data and flag after data writeback */
> -	truncate_inline_data(dn->inode_page);
> +	truncate_inline_inode(dn->inode_page, 0);
>  clear_out:
>  	stat_dec_inline_inode(dn->inode);
>  	f2fs_clear_inline_inode(dn->inode);
> @@ -245,7 +292,7 @@ process_inline:
>  	if (f2fs_has_inline_data(inode)) {
>  		ipage = get_node_page(sbi, inode->i_ino);
>  		f2fs_bug_on(sbi, IS_ERR(ipage));
> -		truncate_inline_data(ipage);
> +		truncate_inline_inode(ipage, 0);
>  		f2fs_clear_inline_inode(inode);
>  		update_inode(inode, ipage);
>  		f2fs_put_page(ipage, 1);
> @@ -363,7 +410,7 @@ static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
>  	set_page_dirty(page);
>  
>  	/* clear inline dir and flag after data writeback */
> -	truncate_inline_data(ipage);
> +	truncate_inline_inode(ipage, 0);
>  
>  	stat_dec_inline_dir(dir);
>  	clear_inode_flag(F2FS_I(dir), FI_INLINE_DENTRY);
> -- 
> 2.3.1

RE: [PATCH] f2fs: fix to truncate inline data past EOF

[Chao Yu]

Hi Jaegeuk,

> -----Original Message-----
> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> Sent: Friday, March 06, 2015 5:34 AM
> To: Chao Yu
> Cc: Changman Lee; linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH] f2fs: fix to truncate inline data past EOF
> 
> Hi Chao,
> 
> On Thu, Mar 05, 2015 at 05:41:32PM +0800, Chao Yu wrote:
> > Previously if inode is with inline data, we will try to invalid partial inline
> > data in page #0 when we truncate size of inode in truncate_partial_data_page().
> > And then we set page #0 to dirty, after this we can synchronize inode page with
> > page #0 at ->writepage().
> >
> > But sometimes we will fail to operate page #0 in truncate_partial_data_page()
> > due to below reason:
> > a) if offset is zero, we will skip setting page #0 to dirty.
> > b) if page #0 is not uptodate, we will fail to update it as it has no mapping
> > data.
> >
> > So with following operations, we will meet recent data which should be
> > truncated.
> >
> > 1.write inline data to file
> > 2.sync first data page to inode page
> > 3.truncate file size to 0
> > 4.truncate file size to max_inline_size
> > 5.echo 1 > /proc/sys/vm/drop_caches
> > 6.read file --> meet original inline data which is remained in inode page.
> >
> > This patch renames truncate_inline_data() to truncate_inline_inode() for code
> > readability, then intruduces new truncate_inline_data() and use it to truncate
> > inline data in page #0 and inode page in truncate_partial_data_page() for
> > fixing.
> >
> > Signed-off-by: Chao Yu <chao2.yu@samsung.com>
> > ---
> >  fs/f2fs/f2fs.h   |  1 +
> >  fs/f2fs/file.c   | 13 ++++++++-----
> >  fs/f2fs/inline.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++-----
> >  3 files changed, 61 insertions(+), 10 deletions(-)
> >
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index 511d6cd..55dbbe7 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
> >   */
> >  bool f2fs_may_inline(struct inode *);
> >  void read_inline_data(struct page *, struct page *);
> > +int truncate_inline_data(struct inode *, u64 from);
> >  int f2fs_read_inline_data(struct inode *, struct page *);
> >  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
> >  int f2fs_convert_inline_inode(struct inode *);
> > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > index f1341c7..6c4443e 100644
> > --- a/fs/f2fs/file.c
> > +++ b/fs/f2fs/file.c
> > @@ -461,6 +461,9 @@ static int truncate_partial_data_page(struct inode *inode, u64 from)
> >  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
> >  	struct page *page;
> >
> > +	if (f2fs_has_inline_data(inode))
> > +		return 0;
> > +
> >  	if (!offset)
> >  		return 0;
> >
> > @@ -497,14 +500,14 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> >  	if (lock)
> >  		f2fs_lock_op(sbi);
> >
> > -	ipage = get_node_page(sbi, inode->i_ino);
> > -	if (IS_ERR(ipage)) {
> > -		err = PTR_ERR(ipage);
> > +	if (f2fs_has_inline_data(inode)) {
> > +		err = truncate_inline_data(inode, from);
> >  		goto out;
> >  	}
> >
> > -	if (f2fs_has_inline_data(inode)) {
> > -		f2fs_put_page(ipage, 1);
> > +	ipage = get_node_page(sbi, inode->i_ino);
> > +	if (IS_ERR(ipage)) {
> > +		err = PTR_ERR(ipage);
> >  		goto out;
> >  	}
> >
> > diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
> > index 4ba9732..a8189c92 100644
> > --- a/fs/f2fs/inline.c
> > +++ b/fs/f2fs/inline.c
> > @@ -50,10 +50,57 @@ void read_inline_data(struct page *page, struct page *ipage)
> >  	SetPageUptodate(page);
> >  }
> >
> > -static void truncate_inline_data(struct page *ipage)
> > +static void truncate_inline_inode(struct page *ipage, u64 from)
> >  {
> > +	void *addr = inline_data_addr(ipage);
> > +
> >  	f2fs_wait_on_page_writeback(ipage, NODE);
> > -	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
> > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> > +}
> > +
> > +int truncate_inline_data(struct inode *inode, u64 from)
> > +{
> > +	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> > +	struct page *page, *ipage;
> > +	void *addr;
> > +	int err = 0;
> > +
> > +	/*
> > +	 * we should never truncate inline data past max inline data size,
> > +	 * because we always convert inline inode to normal one before
> > +	 * truncating real data if new size is past max inline data size.
> > +	 */
> > +	f2fs_bug_on(sbi, from > MAX_INLINE_DATA);
> > +
> > +	if (from == MAX_INLINE_DATA)
> > +		return 0;
> > +
> > +	page = grab_cache_page(inode->i_mapping, 0);
> > +	if (!page)
> > +		return -ENOMEM;
> 
> Do we need to grab and read #0 page?

No need to read #0 page, sorry for the mistake.

> How about checking its cached page after on-disk truncation?
> 
> 1. page = get_node_page()
> 2. check_inline
> 3. truncate_inline_inode
> 4. f2fs_put_page(ipage)
> 
> 5. truncate_partial_data_page(inode, from, force)
> 	if (!offset && !force)
>  		return 0;
> 
> > +
> > +	ipage = get_node_page(sbi, inode->i_ino);
> > +	if (IS_ERR(ipage)) {
> > +		err = PTR_ERR(ipage);
> > +		goto out;
> > +	}
> > +
> > +	if (!f2fs_has_inline_data(inode)) {
> > +		f2fs_put_page(ipage, 1);
> > +		goto out;
> > +	}
> > +
> > +	truncate_inline_inode(ipage, from);
> > +	set_page_dirty(ipage);
> > +
> > +	read_inline_data(page, ipage);
> > +	f2fs_put_page(ipage, 1);
> > +
> > +	addr = inline_data_addr(page);
> > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> 
> It needs to do likewise truncate_partial_data_page.

Do you mean like this?

>From 2e993eee4588cbf2c318eab9916a3aa548ce21f9 Mon Sep 17 00:00:00 2001
From: Chao Yu <chao2.yu@samsung.com>
Date: Fri, 6 Mar 2015 13:29:59 +0800
Subject: [PATCH] f2fs: fix to truncate inline data past EOF

Previously if inode is with inline data, we will try to invalid partial inline
data in page #0 when we truncate size of inode in truncate_partial_data_page().
And then we set page #0 to dirty, after this we can synchronize inode page with
page #0 at ->writepage().

But sometimes we will fail to operate page #0 in truncate_partial_data_page()
due to below reason:
a) if offset is zero, we will skip setting page #0 to dirty.
b) if page #0 is not uptodate, we will fail to update it as it has no mapping
data.

So with following operations, we will meet recent data which should be
truncated.

1.write inline data to file
2.sync first data page to inode page
3.truncate file size to 0
4.truncate file size to max_inline_size
5.echo 1 > /proc/sys/vm/drop_caches
6.read file --> meet original inline data which is remained in inode page.

This patch renames truncate_inline_data() to truncate_inline_inode() for code
readability, then use truncate_inline_inode() to truncate inline data in inode
page in truncate_blocks() and truncate page #0 in truncate_partial_data_page()
for fixing.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
---
 fs/f2fs/f2fs.h   |  1 +
 fs/f2fs/file.c   | 16 +++++++++++-----
 fs/f2fs/inline.c | 26 +++++++++++++++++++++-----
 3 files changed, 33 insertions(+), 10 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 511d6cd..c1ad404 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
  */
 bool f2fs_may_inline(struct inode *);
 void read_inline_data(struct page *, struct page *);
+bool truncate_inline_inode(struct page *, u64);
 int f2fs_read_inline_data(struct inode *, struct page *);
 int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
 int f2fs_convert_inline_inode(struct inode *);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index f1341c7..97abec9 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -456,15 +456,16 @@ void truncate_data_blocks(struct dnode_of_data *dn)
 	truncate_data_blocks_range(dn, ADDRS_PER_BLOCK);
 }
 
-static int truncate_partial_data_page(struct inode *inode, u64 from)
+static int truncate_partial_data_page(struct inode *inode, u64 from,
+								bool force)
 {
 	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
 	struct page *page;
 
-	if (!offset)
+	if (!offset && !force)
 		return 0;
 
-	page = find_data_page(inode, from >> PAGE_CACHE_SHIFT, false);
+	page = find_data_page(inode, from >> PAGE_CACHE_SHIFT, force);
 	if (IS_ERR(page))
 		return 0;
 
@@ -475,7 +476,8 @@ static int truncate_partial_data_page(struct inode *inode, u64 from)
 
 	f2fs_wait_on_page_writeback(page, DATA);
 	zero_user(page, offset, PAGE_CACHE_SIZE - offset);
-	set_page_dirty(page);
+	if (!force)
+		set_page_dirty(page);
 out:
 	f2fs_put_page(page, 1);
 	return 0;
@@ -489,6 +491,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
 	pgoff_t free_from;
 	int count = 0, err = 0;
 	struct page *ipage;
+	bool force = false;
 
 	trace_f2fs_truncate_blocks_enter(inode, from);
 
@@ -504,7 +507,10 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
 	}
 
 	if (f2fs_has_inline_data(inode)) {
+		if (truncate_inline_inode(ipage, from))
+			set_page_dirty(ipage);
 		f2fs_put_page(ipage, 1);
+		force = true;
 		goto out;
 	}
 
@@ -535,7 +541,7 @@ out:
 
 	/* lastly zero out the first data page */
 	if (!err)
-		err = truncate_partial_data_page(inode, from);
+		err = truncate_partial_data_page(inode, from, force);
 
 	trace_f2fs_truncate_blocks_exit(inode, err);
 	return err;
diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index 4ba9732..98e3802 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -50,10 +50,26 @@ void read_inline_data(struct page *page, struct page *ipage)
 	SetPageUptodate(page);
 }
 
-static void truncate_inline_data(struct page *ipage)
+bool truncate_inline_inode(struct page *ipage, u64 from)
 {
+	void *addr;
+
+	/*
+	 * we should never truncate inline data past max inline data size,
+	 * because we always convert inline inode to normal one before
+	 * truncating real data if new size is past max inline data size.
+	 */
+	f2fs_bug_on(F2FS_P_SB(ipage), from > MAX_INLINE_DATA);
+
+	if (from == MAX_INLINE_DATA)
+		return false;
+
+	addr = inline_data_addr(ipage);
+
 	f2fs_wait_on_page_writeback(ipage, NODE);
-	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
+	memset(addr + from, 0, MAX_INLINE_DATA - from);
+
+	return true;
 }
 
 int f2fs_read_inline_data(struct inode *inode, struct page *page)
@@ -131,7 +147,7 @@ no_update:
 	set_inode_flag(F2FS_I(dn->inode), FI_APPEND_WRITE);
 
 	/* clear inline data and flag after data writeback */
-	truncate_inline_data(dn->inode_page);
+	truncate_inline_inode(dn->inode_page, 0);
 clear_out:
 	stat_dec_inline_inode(dn->inode);
 	f2fs_clear_inline_inode(dn->inode);
@@ -245,7 +261,7 @@ process_inline:
 	if (f2fs_has_inline_data(inode)) {
 		ipage = get_node_page(sbi, inode->i_ino);
 		f2fs_bug_on(sbi, IS_ERR(ipage));
-		truncate_inline_data(ipage);
+		truncate_inline_inode(ipage, 0);
 		f2fs_clear_inline_inode(inode);
 		update_inode(inode, ipage);
 		f2fs_put_page(ipage, 1);
@@ -363,7 +379,7 @@ static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
 	set_page_dirty(page);
 
 	/* clear inline dir and flag after data writeback */
-	truncate_inline_data(ipage);
+	truncate_inline_inode(ipage, 0);
 
 	stat_dec_inline_dir(dir);
 	clear_inode_flag(F2FS_I(dir), FI_INLINE_DENTRY);
-- 
2.3.1

Re: [PATCH] f2fs: fix to truncate inline data past EOF

[Jaegeuk Kim]

Hi Chao,


On Mon, Mar 09, 2015 at 10:24:35AM +0800, Chao Yu wrote:
> Hi Jaegeuk,
> 
> > -----Original Message-----
> > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> > Sent: Friday, March 06, 2015 5:34 AM
> > To: Chao Yu
> > Cc: Changman Lee; linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> > Subject: Re: [PATCH] f2fs: fix to truncate inline data past EOF
> > 
> > Hi Chao,
> > 
> > On Thu, Mar 05, 2015 at 05:41:32PM +0800, Chao Yu wrote:
> > > Previously if inode is with inline data, we will try to invalid partial inline
> > > data in page #0 when we truncate size of inode in truncate_partial_data_page().
> > > And then we set page #0 to dirty, after this we can synchronize inode page with
> > > page #0 at ->writepage().
> > >
> > > But sometimes we will fail to operate page #0 in truncate_partial_data_page()
> > > due to below reason:
> > > a) if offset is zero, we will skip setting page #0 to dirty.
> > > b) if page #0 is not uptodate, we will fail to update it as it has no mapping
> > > data.
> > >
> > > So with following operations, we will meet recent data which should be
> > > truncated.
> > >
> > > 1.write inline data to file
> > > 2.sync first data page to inode page
> > > 3.truncate file size to 0
> > > 4.truncate file size to max_inline_size
> > > 5.echo 1 > /proc/sys/vm/drop_caches
> > > 6.read file --> meet original inline data which is remained in inode page.
> > >
> > > This patch renames truncate_inline_data() to truncate_inline_inode() for code
> > > readability, then intruduces new truncate_inline_data() and use it to truncate
> > > inline data in page #0 and inode page in truncate_partial_data_page() for
> > > fixing.
> > >
> > > Signed-off-by: Chao Yu <chao2.yu@samsung.com>
> > > ---
> > >  fs/f2fs/f2fs.h   |  1 +
> > >  fs/f2fs/file.c   | 13 ++++++++-----
> > >  fs/f2fs/inline.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++-----
> > >  3 files changed, 61 insertions(+), 10 deletions(-)
> > >
> > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > > index 511d6cd..55dbbe7 100644
> > > --- a/fs/f2fs/f2fs.h
> > > +++ b/fs/f2fs/f2fs.h
> > > @@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
> > >   */
> > >  bool f2fs_may_inline(struct inode *);
> > >  void read_inline_data(struct page *, struct page *);
> > > +int truncate_inline_data(struct inode *, u64 from);
> > >  int f2fs_read_inline_data(struct inode *, struct page *);
> > >  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
> > >  int f2fs_convert_inline_inode(struct inode *);
> > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > > index f1341c7..6c4443e 100644
> > > --- a/fs/f2fs/file.c
> > > +++ b/fs/f2fs/file.c
> > > @@ -461,6 +461,9 @@ static int truncate_partial_data_page(struct inode *inode, u64 from)
> > >  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
> > >  	struct page *page;
> > >
> > > +	if (f2fs_has_inline_data(inode))
> > > +		return 0;
> > > +
> > >  	if (!offset)
> > >  		return 0;
> > >
> > > @@ -497,14 +500,14 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> > >  	if (lock)
> > >  		f2fs_lock_op(sbi);
> > >
> > > -	ipage = get_node_page(sbi, inode->i_ino);
> > > -	if (IS_ERR(ipage)) {
> > > -		err = PTR_ERR(ipage);
> > > +	if (f2fs_has_inline_data(inode)) {
> > > +		err = truncate_inline_data(inode, from);
> > >  		goto out;
> > >  	}
> > >
> > > -	if (f2fs_has_inline_data(inode)) {
> > > -		f2fs_put_page(ipage, 1);
> > > +	ipage = get_node_page(sbi, inode->i_ino);
> > > +	if (IS_ERR(ipage)) {
> > > +		err = PTR_ERR(ipage);
> > >  		goto out;
> > >  	}
> > >
> > > diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
> > > index 4ba9732..a8189c92 100644
> > > --- a/fs/f2fs/inline.c
> > > +++ b/fs/f2fs/inline.c
> > > @@ -50,10 +50,57 @@ void read_inline_data(struct page *page, struct page *ipage)
> > >  	SetPageUptodate(page);
> > >  }
> > >
> > > -static void truncate_inline_data(struct page *ipage)
> > > +static void truncate_inline_inode(struct page *ipage, u64 from)
> > >  {
> > > +	void *addr = inline_data_addr(ipage);
> > > +
> > >  	f2fs_wait_on_page_writeback(ipage, NODE);
> > > -	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
> > > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> > > +}
> > > +
> > > +int truncate_inline_data(struct inode *inode, u64 from)
> > > +{
> > > +	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> > > +	struct page *page, *ipage;
> > > +	void *addr;
> > > +	int err = 0;
> > > +
> > > +	/*
> > > +	 * we should never truncate inline data past max inline data size,
> > > +	 * because we always convert inline inode to normal one before
> > > +	 * truncating real data if new size is past max inline data size.
> > > +	 */
> > > +	f2fs_bug_on(sbi, from > MAX_INLINE_DATA);
> > > +
> > > +	if (from == MAX_INLINE_DATA)
> > > +		return 0;
> > > +
> > > +	page = grab_cache_page(inode->i_mapping, 0);
> > > +	if (!page)
> > > +		return -ENOMEM;
> > 
> > Do we need to grab and read #0 page?
> 
> No need to read #0 page, sorry for the mistake.
> 
> > How about checking its cached page after on-disk truncation?
> > 
> > 1. page = get_node_page()
> > 2. check_inline
> > 3. truncate_inline_inode
> > 4. f2fs_put_page(ipage)
> > 
> > 5. truncate_partial_data_page(inode, from, force)
> > 	if (!offset && !force)
> >  		return 0;
> > 
> > > +
> > > +	ipage = get_node_page(sbi, inode->i_ino);
> > > +	if (IS_ERR(ipage)) {
> > > +		err = PTR_ERR(ipage);
> > > +		goto out;
> > > +	}
> > > +
> > > +	if (!f2fs_has_inline_data(inode)) {
> > > +		f2fs_put_page(ipage, 1);
> > > +		goto out;
> > > +	}
> > > +
> > > +	truncate_inline_inode(ipage, from);
> > > +	set_page_dirty(ipage);
> > > +
> > > +	read_inline_data(page, ipage);
> > > +	f2fs_put_page(ipage, 1);
> > > +
> > > +	addr = inline_data_addr(page);
> > > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> > 
> > It needs to do likewise truncate_partial_data_page.
> 
> Do you mean like this?

I meant this.

Anyway, I also wrote a patch about your testing scenario wrt inline_data.
So, let me submit the patch sooner or later to xfstests mailing list.

Thanks,

---
 fs/f2fs/f2fs.h   |  1 +
 fs/f2fs/file.c   | 10 +++++++---
 fs/f2fs/inline.c | 12 +++++++-----
 3 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 31b440e..b222b3a 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1760,6 +1760,7 @@ extern struct kmem_cache *inode_entry_slab;
  */
 bool f2fs_may_inline(struct inode *);
 void read_inline_data(struct page *, struct page *);
+void truncate_inline_inode(struct page *, u64);
 int f2fs_read_inline_data(struct inode *, struct page *);
 int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
 int f2fs_convert_inline_inode(struct inode *);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index f1341c7..ab249dd 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -456,12 +456,12 @@ void truncate_data_blocks(struct dnode_of_data *dn)
 	truncate_data_blocks_range(dn, ADDRS_PER_BLOCK);
 }
 
-static int truncate_partial_data_page(struct inode *inode, u64 from)
+static int truncate_partial_data_page(struct inode *inode, u64 from, bool force)
 {
 	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
 	struct page *page;
 
-	if (!offset)
+	if (!offset && !force)
 		return 0;
 
 	page = find_data_page(inode, from >> PAGE_CACHE_SHIFT, false);
@@ -489,6 +489,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
 	pgoff_t free_from;
 	int count = 0, err = 0;
 	struct page *ipage;
+	bool truncate_page = false;
 
 	trace_f2fs_truncate_blocks_enter(inode, from);
 
@@ -504,6 +505,9 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
 	}
 
 	if (f2fs_has_inline_data(inode)) {
+		truncate_inline_inode(ipage, from);
+		set_page_dirty(ipage);
+		truncate_page = true;
 		f2fs_put_page(ipage, 1);
 		goto out;
 	}
@@ -535,7 +539,7 @@ out:
 
 	/* lastly zero out the first data page */
 	if (!err)
-		err = truncate_partial_data_page(inode, from);
+		err = truncate_partial_data_page(inode, from, truncate_page);
 
 	trace_f2fs_truncate_blocks_exit(inode, err);
 	return err;
diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index ee0984c..b236e30 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -50,10 +50,12 @@ void read_inline_data(struct page *page, struct page *ipage)
 	SetPageUptodate(page);
 }
 
-static void truncate_inline_data(struct page *ipage)
+void truncate_inline_inode(struct page *ipage, u64 from)
 {
+	void *addr = inline_data_addr(ipage);
+
 	f2fs_wait_on_page_writeback(ipage, NODE);
-	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
+	memset(addr + from, 0, MAX_INLINE_DATA - from);
 }
 
 int f2fs_read_inline_data(struct inode *inode, struct page *page)
@@ -131,7 +133,7 @@ no_update:
 	set_inode_flag(F2FS_I(dn->inode), FI_APPEND_WRITE);
 
 	/* clear inline data and flag after data writeback */
-	truncate_inline_data(dn->inode_page);
+	truncate_inline_inode(dn->inode_page, 0);
 clear_out:
 	stat_dec_inline_inode(dn->inode);
 	f2fs_clear_inline_inode(dn->inode);
@@ -245,7 +247,7 @@ process_inline:
 	if (f2fs_has_inline_data(inode)) {
 		ipage = get_node_page(sbi, inode->i_ino);
 		f2fs_bug_on(sbi, IS_ERR(ipage));
-		truncate_inline_data(ipage);
+		truncate_inline_inode(ipage, 0);
 		f2fs_clear_inline_inode(inode);
 		update_inode(inode, ipage);
 		f2fs_put_page(ipage, 1);
@@ -363,7 +365,7 @@ static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
 	set_page_dirty(page);
 
 	/* clear inline dir and flag after data writeback */
-	truncate_inline_data(ipage);
+	truncate_inline_inode(ipage, 0);
 
 	stat_dec_inline_dir(dir);
 	clear_inode_flag(F2FS_I(dir), FI_INLINE_DENTRY);
-- 
2.1.1

RE: [PATCH] f2fs: fix to truncate inline data past EOF

[Chao Yu]

Hi Jaegeuk,

> -----Original Message-----
> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> Sent: Monday, March 09, 2015 11:49 AM
> To: Chao Yu
> Cc: 'Changman Lee'; linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH] f2fs: fix to truncate inline data past EOF
> 
> Hi Chao,
> 
> 
> On Mon, Mar 09, 2015 at 10:24:35AM +0800, Chao Yu wrote:
> > Hi Jaegeuk,
> >
> > > -----Original Message-----
> > > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> > > Sent: Friday, March 06, 2015 5:34 AM
> > > To: Chao Yu
> > > Cc: Changman Lee; linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> > > Subject: Re: [PATCH] f2fs: fix to truncate inline data past EOF
> > >
> > > Hi Chao,
> > >
> > > On Thu, Mar 05, 2015 at 05:41:32PM +0800, Chao Yu wrote:
> > > > Previously if inode is with inline data, we will try to invalid partial inline
> > > > data in page #0 when we truncate size of inode in truncate_partial_data_page().
> > > > And then we set page #0 to dirty, after this we can synchronize inode page with
> > > > page #0 at ->writepage().
> > > >
> > > > But sometimes we will fail to operate page #0 in truncate_partial_data_page()
> > > > due to below reason:
> > > > a) if offset is zero, we will skip setting page #0 to dirty.
> > > > b) if page #0 is not uptodate, we will fail to update it as it has no mapping
> > > > data.
> > > >
> > > > So with following operations, we will meet recent data which should be
> > > > truncated.
> > > >
> > > > 1.write inline data to file
> > > > 2.sync first data page to inode page
> > > > 3.truncate file size to 0
> > > > 4.truncate file size to max_inline_size
> > > > 5.echo 1 > /proc/sys/vm/drop_caches
> > > > 6.read file --> meet original inline data which is remained in inode page.
> > > >
> > > > This patch renames truncate_inline_data() to truncate_inline_inode() for code
> > > > readability, then intruduces new truncate_inline_data() and use it to truncate
> > > > inline data in page #0 and inode page in truncate_partial_data_page() for
> > > > fixing.
> > > >
> > > > Signed-off-by: Chao Yu <chao2.yu@samsung.com>
> > > > ---
> > > >  fs/f2fs/f2fs.h   |  1 +
> > > >  fs/f2fs/file.c   | 13 ++++++++-----
> > > >  fs/f2fs/inline.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++-----
> > > >  3 files changed, 61 insertions(+), 10 deletions(-)
> > > >
> > > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > > > index 511d6cd..55dbbe7 100644
> > > > --- a/fs/f2fs/f2fs.h
> > > > +++ b/fs/f2fs/f2fs.h
> > > > @@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
> > > >   */
> > > >  bool f2fs_may_inline(struct inode *);
> > > >  void read_inline_data(struct page *, struct page *);
> > > > +int truncate_inline_data(struct inode *, u64 from);
> > > >  int f2fs_read_inline_data(struct inode *, struct page *);
> > > >  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
> > > >  int f2fs_convert_inline_inode(struct inode *);
> > > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > > > index f1341c7..6c4443e 100644
> > > > --- a/fs/f2fs/file.c
> > > > +++ b/fs/f2fs/file.c
> > > > @@ -461,6 +461,9 @@ static int truncate_partial_data_page(struct inode *inode, u64 from)
> > > >  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
> > > >  	struct page *page;
> > > >
> > > > +	if (f2fs_has_inline_data(inode))
> > > > +		return 0;
> > > > +
> > > >  	if (!offset)
> > > >  		return 0;
> > > >
> > > > @@ -497,14 +500,14 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> > > >  	if (lock)
> > > >  		f2fs_lock_op(sbi);
> > > >
> > > > -	ipage = get_node_page(sbi, inode->i_ino);
> > > > -	if (IS_ERR(ipage)) {
> > > > -		err = PTR_ERR(ipage);
> > > > +	if (f2fs_has_inline_data(inode)) {
> > > > +		err = truncate_inline_data(inode, from);
> > > >  		goto out;
> > > >  	}
> > > >
> > > > -	if (f2fs_has_inline_data(inode)) {
> > > > -		f2fs_put_page(ipage, 1);
> > > > +	ipage = get_node_page(sbi, inode->i_ino);
> > > > +	if (IS_ERR(ipage)) {
> > > > +		err = PTR_ERR(ipage);
> > > >  		goto out;
> > > >  	}
> > > >
> > > > diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
> > > > index 4ba9732..a8189c92 100644
> > > > --- a/fs/f2fs/inline.c
> > > > +++ b/fs/f2fs/inline.c
> > > > @@ -50,10 +50,57 @@ void read_inline_data(struct page *page, struct page *ipage)
> > > >  	SetPageUptodate(page);
> > > >  }
> > > >
> > > > -static void truncate_inline_data(struct page *ipage)
> > > > +static void truncate_inline_inode(struct page *ipage, u64 from)
> > > >  {
> > > > +	void *addr = inline_data_addr(ipage);
> > > > +
> > > >  	f2fs_wait_on_page_writeback(ipage, NODE);
> > > > -	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
> > > > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> > > > +}
> > > > +
> > > > +int truncate_inline_data(struct inode *inode, u64 from)
> > > > +{
> > > > +	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> > > > +	struct page *page, *ipage;
> > > > +	void *addr;
> > > > +	int err = 0;
> > > > +
> > > > +	/*
> > > > +	 * we should never truncate inline data past max inline data size,
> > > > +	 * because we always convert inline inode to normal one before
> > > > +	 * truncating real data if new size is past max inline data size.
> > > > +	 */
> > > > +	f2fs_bug_on(sbi, from > MAX_INLINE_DATA);
> > > > +
> > > > +	if (from == MAX_INLINE_DATA)
> > > > +		return 0;
> > > > +
> > > > +	page = grab_cache_page(inode->i_mapping, 0);
> > > > +	if (!page)
> > > > +		return -ENOMEM;
> > >
> > > Do we need to grab and read #0 page?
> >
> > No need to read #0 page, sorry for the mistake.
> >
> > > How about checking its cached page after on-disk truncation?
> > >
> > > 1. page = get_node_page()
> > > 2. check_inline
> > > 3. truncate_inline_inode
> > > 4. f2fs_put_page(ipage)
> > >
> > > 5. truncate_partial_data_page(inode, from, force)
> > > 	if (!offset && !force)
> > >  		return 0;
> > >
> > > > +
> > > > +	ipage = get_node_page(sbi, inode->i_ino);
> > > > +	if (IS_ERR(ipage)) {
> > > > +		err = PTR_ERR(ipage);
> > > > +		goto out;
> > > > +	}
> > > > +
> > > > +	if (!f2fs_has_inline_data(inode)) {
> > > > +		f2fs_put_page(ipage, 1);
> > > > +		goto out;
> > > > +	}
> > > > +
> > > > +	truncate_inline_inode(ipage, from);
> > > > +	set_page_dirty(ipage);
> > > > +
> > > > +	read_inline_data(page, ipage);
> > > > +	f2fs_put_page(ipage, 1);
> > > > +
> > > > +	addr = inline_data_addr(page);
> > > > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> > >
> > > It needs to do likewise truncate_partial_data_page.
> >
> > Do you mean like this?
> 
> I meant this.
> 
> Anyway, I also wrote a patch about your testing scenario wrt inline_data.
> So, let me submit the patch sooner or later to xfstests mailing list.

Sounds good! :)

> 
> Thanks,
> 
> ---
>  fs/f2fs/f2fs.h   |  1 +
>  fs/f2fs/file.c   | 10 +++++++---
>  fs/f2fs/inline.c | 12 +++++++-----
>  3 files changed, 15 insertions(+), 8 deletions(-)
> 
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 31b440e..b222b3a 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -1760,6 +1760,7 @@ extern struct kmem_cache *inode_entry_slab;
>   */
>  bool f2fs_may_inline(struct inode *);
>  void read_inline_data(struct page *, struct page *);
> +void truncate_inline_inode(struct page *, u64);
>  int f2fs_read_inline_data(struct inode *, struct page *);
>  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
>  int f2fs_convert_inline_inode(struct inode *);
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index f1341c7..ab249dd 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -456,12 +456,12 @@ void truncate_data_blocks(struct dnode_of_data *dn)
>  	truncate_data_blocks_range(dn, ADDRS_PER_BLOCK);
>  }
> 
> -static int truncate_partial_data_page(struct inode *inode, u64 from)
> +static int truncate_partial_data_page(struct inode *inode, u64 from, bool force)
>  {
>  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
>  	struct page *page;
> 
> -	if (!offset)
> +	if (!offset && !force)

We truncate on-disk inode page and #0 page separately, so IMO there is a very
small chance the following issue will occur.

(0 < truncated_size < MAX_INLINE_SIZE)
->f2fs_setattr
  ->truncate_setsize #0 page has been truncated partially
  ->f2fs_truncate
    ->truncate_blocks
					invalidate #0 page by reclaimer
					update #0 page with original data in inode page by reader
      ->truncate_inline_inode
      ->truncate_partial_data_page
        we will fail to truncate #0 page because we can't find valid blkaddr for
        #0 page in find_data_page(,,false)

How about using find_data_page(,,true) to check weather this page is update or not
for this condition.

>  		return 0;
> 
>  	page = find_data_page(inode, from >> PAGE_CACHE_SHIFT, false);
> @@ -489,6 +489,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
>  	pgoff_t free_from;
>  	int count = 0, err = 0;
>  	struct page *ipage;
> +	bool truncate_page = false;
> 
>  	trace_f2fs_truncate_blocks_enter(inode, from);
> 
> @@ -504,6 +505,9 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
>  	}
> 
>  	if (f2fs_has_inline_data(inode)) {
> +		truncate_inline_inode(ipage, from);
> +		set_page_dirty(ipage);

If @from is the same as MAX_INLINE_DATA, we will change nothing in inode page,
How about skipping set_page_dirty for inode page in this condition?

Thanks,

> +		truncate_page = true;
>  		f2fs_put_page(ipage, 1);
>  		goto out;
>  	}
> @@ -535,7 +539,7 @@ out:
> 
>  	/* lastly zero out the first data page */
>  	if (!err)
> -		err = truncate_partial_data_page(inode, from);
> +		err = truncate_partial_data_page(inode, from, truncate_page);
> 
>  	trace_f2fs_truncate_blocks_exit(inode, err);
>  	return err;
> diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
> index ee0984c..b236e30 100644
> --- a/fs/f2fs/inline.c
> +++ b/fs/f2fs/inline.c
> @@ -50,10 +50,12 @@ void read_inline_data(struct page *page, struct page *ipage)
>  	SetPageUptodate(page);
>  }
> 
> -static void truncate_inline_data(struct page *ipage)
> +void truncate_inline_inode(struct page *ipage, u64 from)
>  {
> +	void *addr = inline_data_addr(ipage);
> +
>  	f2fs_wait_on_page_writeback(ipage, NODE);
> -	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
> +	memset(addr + from, 0, MAX_INLINE_DATA - from);
>  }
> 
>  int f2fs_read_inline_data(struct inode *inode, struct page *page)
> @@ -131,7 +133,7 @@ no_update:
>  	set_inode_flag(F2FS_I(dn->inode), FI_APPEND_WRITE);
> 
>  	/* clear inline data and flag after data writeback */
> -	truncate_inline_data(dn->inode_page);
> +	truncate_inline_inode(dn->inode_page, 0);
>  clear_out:
>  	stat_dec_inline_inode(dn->inode);
>  	f2fs_clear_inline_inode(dn->inode);
> @@ -245,7 +247,7 @@ process_inline:
>  	if (f2fs_has_inline_data(inode)) {
>  		ipage = get_node_page(sbi, inode->i_ino);
>  		f2fs_bug_on(sbi, IS_ERR(ipage));
> -		truncate_inline_data(ipage);
> +		truncate_inline_inode(ipage, 0);
>  		f2fs_clear_inline_inode(inode);
>  		update_inode(inode, ipage);
>  		f2fs_put_page(ipage, 1);
> @@ -363,7 +365,7 @@ static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
>  	set_page_dirty(page);
> 
>  	/* clear inline dir and flag after data writeback */
> -	truncate_inline_data(ipage);
> +	truncate_inline_inode(ipage, 0);
> 
>  	stat_dec_inline_dir(dir);
>  	clear_inode_flag(F2FS_I(dir), FI_INLINE_DENTRY);
> --
> 2.1.1

Re: [PATCH] f2fs: fix to truncate inline data past EOF

[Jaegeuk Kim]

Hi Chao,

On Mon, Mar 09, 2015 at 04:30:32PM +0800, Chao Yu wrote:
> Hi Jaegeuk,
> 
> > -----Original Message-----
> > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> > Sent: Monday, March 09, 2015 11:49 AM
> > To: Chao Yu
> > Cc: 'Changman Lee'; linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> > Subject: Re: [PATCH] f2fs: fix to truncate inline data past EOF
> > 
> > Hi Chao,
> > 
> > 
> > On Mon, Mar 09, 2015 at 10:24:35AM +0800, Chao Yu wrote:
> > > Hi Jaegeuk,
> > >
> > > > -----Original Message-----
> > > > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> > > > Sent: Friday, March 06, 2015 5:34 AM
> > > > To: Chao Yu
> > > > Cc: Changman Lee; linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> > > > Subject: Re: [PATCH] f2fs: fix to truncate inline data past EOF
> > > >
> > > > Hi Chao,
> > > >
> > > > On Thu, Mar 05, 2015 at 05:41:32PM +0800, Chao Yu wrote:
> > > > > Previously if inode is with inline data, we will try to invalid partial inline
> > > > > data in page #0 when we truncate size of inode in truncate_partial_data_page().
> > > > > And then we set page #0 to dirty, after this we can synchronize inode page with
> > > > > page #0 at ->writepage().
> > > > >
> > > > > But sometimes we will fail to operate page #0 in truncate_partial_data_page()
> > > > > due to below reason:
> > > > > a) if offset is zero, we will skip setting page #0 to dirty.
> > > > > b) if page #0 is not uptodate, we will fail to update it as it has no mapping
> > > > > data.
> > > > >
> > > > > So with following operations, we will meet recent data which should be
> > > > > truncated.
> > > > >
> > > > > 1.write inline data to file
> > > > > 2.sync first data page to inode page
> > > > > 3.truncate file size to 0
> > > > > 4.truncate file size to max_inline_size
> > > > > 5.echo 1 > /proc/sys/vm/drop_caches
> > > > > 6.read file --> meet original inline data which is remained in inode page.
> > > > >
> > > > > This patch renames truncate_inline_data() to truncate_inline_inode() for code
> > > > > readability, then intruduces new truncate_inline_data() and use it to truncate
> > > > > inline data in page #0 and inode page in truncate_partial_data_page() for
> > > > > fixing.
> > > > >
> > > > > Signed-off-by: Chao Yu <chao2.yu@samsung.com>
> > > > > ---
> > > > >  fs/f2fs/f2fs.h   |  1 +
> > > > >  fs/f2fs/file.c   | 13 ++++++++-----
> > > > >  fs/f2fs/inline.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++-----
> > > > >  3 files changed, 61 insertions(+), 10 deletions(-)
> > > > >
> > > > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > > > > index 511d6cd..55dbbe7 100644
> > > > > --- a/fs/f2fs/f2fs.h
> > > > > +++ b/fs/f2fs/f2fs.h
> > > > > @@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
> > > > >   */
> > > > >  bool f2fs_may_inline(struct inode *);
> > > > >  void read_inline_data(struct page *, struct page *);
> > > > > +int truncate_inline_data(struct inode *, u64 from);
> > > > >  int f2fs_read_inline_data(struct inode *, struct page *);
> > > > >  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
> > > > >  int f2fs_convert_inline_inode(struct inode *);
> > > > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > > > > index f1341c7..6c4443e 100644
> > > > > --- a/fs/f2fs/file.c
> > > > > +++ b/fs/f2fs/file.c
> > > > > @@ -461,6 +461,9 @@ static int truncate_partial_data_page(struct inode *inode, u64 from)
> > > > >  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
> > > > >  	struct page *page;
> > > > >
> > > > > +	if (f2fs_has_inline_data(inode))
> > > > > +		return 0;
> > > > > +
> > > > >  	if (!offset)
> > > > >  		return 0;
> > > > >
> > > > > @@ -497,14 +500,14 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> > > > >  	if (lock)
> > > > >  		f2fs_lock_op(sbi);
> > > > >
> > > > > -	ipage = get_node_page(sbi, inode->i_ino);
> > > > > -	if (IS_ERR(ipage)) {
> > > > > -		err = PTR_ERR(ipage);
> > > > > +	if (f2fs_has_inline_data(inode)) {
> > > > > +		err = truncate_inline_data(inode, from);
> > > > >  		goto out;
> > > > >  	}
> > > > >
> > > > > -	if (f2fs_has_inline_data(inode)) {
> > > > > -		f2fs_put_page(ipage, 1);
> > > > > +	ipage = get_node_page(sbi, inode->i_ino);
> > > > > +	if (IS_ERR(ipage)) {
> > > > > +		err = PTR_ERR(ipage);
> > > > >  		goto out;
> > > > >  	}
> > > > >
> > > > > diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
> > > > > index 4ba9732..a8189c92 100644
> > > > > --- a/fs/f2fs/inline.c
> > > > > +++ b/fs/f2fs/inline.c
> > > > > @@ -50,10 +50,57 @@ void read_inline_data(struct page *page, struct page *ipage)
> > > > >  	SetPageUptodate(page);
> > > > >  }
> > > > >
> > > > > -static void truncate_inline_data(struct page *ipage)
> > > > > +static void truncate_inline_inode(struct page *ipage, u64 from)
> > > > >  {
> > > > > +	void *addr = inline_data_addr(ipage);
> > > > > +
> > > > >  	f2fs_wait_on_page_writeback(ipage, NODE);
> > > > > -	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
> > > > > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> > > > > +}
> > > > > +
> > > > > +int truncate_inline_data(struct inode *inode, u64 from)
> > > > > +{
> > > > > +	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> > > > > +	struct page *page, *ipage;
> > > > > +	void *addr;
> > > > > +	int err = 0;
> > > > > +
> > > > > +	/*
> > > > > +	 * we should never truncate inline data past max inline data size,
> > > > > +	 * because we always convert inline inode to normal one before
> > > > > +	 * truncating real data if new size is past max inline data size.
> > > > > +	 */
> > > > > +	f2fs_bug_on(sbi, from > MAX_INLINE_DATA);
> > > > > +
> > > > > +	if (from == MAX_INLINE_DATA)
> > > > > +		return 0;
> > > > > +
> > > > > +	page = grab_cache_page(inode->i_mapping, 0);
> > > > > +	if (!page)
> > > > > +		return -ENOMEM;
> > > >
> > > > Do we need to grab and read #0 page?
> > >
> > > No need to read #0 page, sorry for the mistake.
> > >
> > > > How about checking its cached page after on-disk truncation?
> > > >
> > > > 1. page = get_node_page()
> > > > 2. check_inline
> > > > 3. truncate_inline_inode
> > > > 4. f2fs_put_page(ipage)
> > > >
> > > > 5. truncate_partial_data_page(inode, from, force)
> > > > 	if (!offset && !force)
> > > >  		return 0;
> > > >
> > > > > +
> > > > > +	ipage = get_node_page(sbi, inode->i_ino);
> > > > > +	if (IS_ERR(ipage)) {
> > > > > +		err = PTR_ERR(ipage);
> > > > > +		goto out;
> > > > > +	}
> > > > > +
> > > > > +	if (!f2fs_has_inline_data(inode)) {
> > > > > +		f2fs_put_page(ipage, 1);
> > > > > +		goto out;
> > > > > +	}
> > > > > +
> > > > > +	truncate_inline_inode(ipage, from);
> > > > > +	set_page_dirty(ipage);
> > > > > +
> > > > > +	read_inline_data(page, ipage);
> > > > > +	f2fs_put_page(ipage, 1);
> > > > > +
> > > > > +	addr = inline_data_addr(page);
> > > > > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> > > >
> > > > It needs to do likewise truncate_partial_data_page.
> > >
> > > Do you mean like this?
> > 
> > I meant this.
> > 
> > Anyway, I also wrote a patch about your testing scenario wrt inline_data.
> > So, let me submit the patch sooner or later to xfstests mailing list.
> 
> Sounds good! :)
> 
> > 
> > Thanks,
> > 
> > ---
> >  fs/f2fs/f2fs.h   |  1 +
> >  fs/f2fs/file.c   | 10 +++++++---
> >  fs/f2fs/inline.c | 12 +++++++-----
> >  3 files changed, 15 insertions(+), 8 deletions(-)
> > 
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index 31b440e..b222b3a 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -1760,6 +1760,7 @@ extern struct kmem_cache *inode_entry_slab;
> >   */
> >  bool f2fs_may_inline(struct inode *);
> >  void read_inline_data(struct page *, struct page *);
> > +void truncate_inline_inode(struct page *, u64);
> >  int f2fs_read_inline_data(struct inode *, struct page *);
> >  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
> >  int f2fs_convert_inline_inode(struct inode *);
> > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > index f1341c7..ab249dd 100644
> > --- a/fs/f2fs/file.c
> > +++ b/fs/f2fs/file.c
> > @@ -456,12 +456,12 @@ void truncate_data_blocks(struct dnode_of_data *dn)
> >  	truncate_data_blocks_range(dn, ADDRS_PER_BLOCK);
> >  }
> > 
> > -static int truncate_partial_data_page(struct inode *inode, u64 from)
> > +static int truncate_partial_data_page(struct inode *inode, u64 from, bool force)
> >  {
> >  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
> >  	struct page *page;
> > 
> > -	if (!offset)
> > +	if (!offset && !force)
> 
> We truncate on-disk inode page and #0 page separately, so IMO there is a very
> small chance the following issue will occur.
> 
> (0 < truncated_size < MAX_INLINE_SIZE)
> ->f2fs_setattr
>   ->truncate_setsize #0 page has been truncated partially
>   ->f2fs_truncate
>     ->truncate_blocks
> 					invalidate #0 page by reclaimer
> 					update #0 page with original data in inode page by reader

					truncate_setsize called truncate_pagesize.
					so #0 page was truncated successfully.

>       ->truncate_inline_inode
>       ->truncate_partial_data_page
>         we will fail to truncate #0 page because we can't find valid blkaddr for
>         #0 page in find_data_page(,,false)
> 
> How about using find_data_page(,,true) to check weather this page is update or not
> for this condition.

Oh, I realized that we don't need to call truncate_partial_data_page, since the
cached #0 page was truncated already. We don't care about that.
So, do we need to add just truncate_inline_inode() like below?

> 
> >  		return 0;
> > 
> >  	page = find_data_page(inode, from >> PAGE_CACHE_SHIFT, false);
> > @@ -489,6 +489,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> >  	pgoff_t free_from;
> >  	int count = 0, err = 0;
> >  	struct page *ipage;
> > +	bool truncate_page = false;
> > 
> >  	trace_f2fs_truncate_blocks_enter(inode, from);
> > 
> > @@ -504,6 +505,9 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> >  	}
> > 
> >  	if (f2fs_has_inline_data(inode)) {
> > +		truncate_inline_inode(ipage, from);
> > +		set_page_dirty(ipage);
> 
> If @from is the same as MAX_INLINE_DATA, we will change nothing in inode page,
> How about skipping set_page_dirty for inode page in this condition?

Agreed.
How about adding this in truncate_inline_inode?

	if (from >= MAX_INLINE_DATA)
		return;
	...
	set_page_dirty(ipage);

Thanks,

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/f2fs/f2fs.h   |  1 +
 fs/f2fs/file.c   |  1 +
 fs/f2fs/inline.c | 16 +++++++++++-----
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 511d6cd..5cd3a2f 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
  */
 bool f2fs_may_inline(struct inode *);
 void read_inline_data(struct page *, struct page *);
+void truncate_inline_inode(struct page *, u64);
 int f2fs_read_inline_data(struct inode *, struct page *);
 int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
 int f2fs_convert_inline_inode(struct inode *);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index f1341c7..b6b6a04 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -504,6 +504,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
 	}
 
 	if (f2fs_has_inline_data(inode)) {
+		truncate_inline_inode(ipage, from);
 		f2fs_put_page(ipage, 1);
 		goto out;
 	}
diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index 4ba9732..40bbf96 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -50,10 +50,16 @@ void read_inline_data(struct page *page, struct page *ipage)
 	SetPageUptodate(page);
 }
 
-static void truncate_inline_data(struct page *ipage)
+void truncate_inline_inode(struct page *ipage, u64 from)
 {
+	void *addr = inline_data_addr(ipage);
+
+	if (from >= MAX_INLIE_DATA)
+		return;
+
 	f2fs_wait_on_page_writeback(ipage, NODE);
-	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
+	memset(addr + from, 0, MAX_INLINE_DATA - from);
+	set_page_dirty(ipage);
 }
 
 int f2fs_read_inline_data(struct inode *inode, struct page *page)
@@ -131,7 +137,7 @@ no_update:
 	set_inode_flag(F2FS_I(dn->inode), FI_APPEND_WRITE);
 
 	/* clear inline data and flag after data writeback */
-	truncate_inline_data(dn->inode_page);
+	truncate_inline_inode(dn->inode_page, 0);
 clear_out:
 	stat_dec_inline_inode(dn->inode);
 	f2fs_clear_inline_inode(dn->inode);
@@ -245,7 +251,7 @@ process_inline:
 	if (f2fs_has_inline_data(inode)) {
 		ipage = get_node_page(sbi, inode->i_ino);
 		f2fs_bug_on(sbi, IS_ERR(ipage));
-		truncate_inline_data(ipage);
+		truncate_inline_inode(ipage, 0);
 		f2fs_clear_inline_inode(inode);
 		update_inode(inode, ipage);
 		f2fs_put_page(ipage, 1);
@@ -363,7 +369,7 @@ static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
 	set_page_dirty(page);
 
 	/* clear inline dir and flag after data writeback */
-	truncate_inline_data(ipage);
+	truncate_inline_inode(ipage, 0);
 
 	stat_dec_inline_dir(dir);
 	clear_inode_flag(F2FS_I(dir), FI_INLINE_DENTRY);
-- 
2.1.1

RE: [PATCH] f2fs: fix to truncate inline data past EOF

[Chao Yu]

Hi Jaegeuk,

> -----Original Message-----
> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> Sent: Tuesday, March 10, 2015 12:16 AM
> To: Chao Yu
> Cc: 'Changman Lee'; linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH] f2fs: fix to truncate inline data past EOF
> 
> Hi Chao,
> 
> On Mon, Mar 09, 2015 at 04:30:32PM +0800, Chao Yu wrote:
> > Hi Jaegeuk,
> >
> > > -----Original Message-----
> > > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> > > Sent: Monday, March 09, 2015 11:49 AM
> > > To: Chao Yu
> > > Cc: 'Changman Lee'; linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> > > Subject: Re: [PATCH] f2fs: fix to truncate inline data past EOF
> > >
> > > Hi Chao,
> > >
> > >
> > > On Mon, Mar 09, 2015 at 10:24:35AM +0800, Chao Yu wrote:
> > > > Hi Jaegeuk,
> > > >
> > > > > -----Original Message-----
> > > > > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> > > > > Sent: Friday, March 06, 2015 5:34 AM
> > > > > To: Chao Yu
> > > > > Cc: Changman Lee; linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> > > > > Subject: Re: [PATCH] f2fs: fix to truncate inline data past EOF
> > > > >
> > > > > Hi Chao,
> > > > >
> > > > > On Thu, Mar 05, 2015 at 05:41:32PM +0800, Chao Yu wrote:
> > > > > > Previously if inode is with inline data, we will try to invalid partial inline
> > > > > > data in page #0 when we truncate size of inode in truncate_partial_data_page().
> > > > > > And then we set page #0 to dirty, after this we can synchronize inode page with
> > > > > > page #0 at ->writepage().
> > > > > >
> > > > > > But sometimes we will fail to operate page #0 in truncate_partial_data_page()
> > > > > > due to below reason:
> > > > > > a) if offset is zero, we will skip setting page #0 to dirty.
> > > > > > b) if page #0 is not uptodate, we will fail to update it as it has no mapping
> > > > > > data.
> > > > > >
> > > > > > So with following operations, we will meet recent data which should be
> > > > > > truncated.
> > > > > >
> > > > > > 1.write inline data to file
> > > > > > 2.sync first data page to inode page
> > > > > > 3.truncate file size to 0
> > > > > > 4.truncate file size to max_inline_size
> > > > > > 5.echo 1 > /proc/sys/vm/drop_caches
> > > > > > 6.read file --> meet original inline data which is remained in inode page.
> > > > > >
> > > > > > This patch renames truncate_inline_data() to truncate_inline_inode() for code
> > > > > > readability, then intruduces new truncate_inline_data() and use it to truncate
> > > > > > inline data in page #0 and inode page in truncate_partial_data_page() for
> > > > > > fixing.
> > > > > >
> > > > > > Signed-off-by: Chao Yu <chao2.yu@samsung.com>
> > > > > > ---
> > > > > >  fs/f2fs/f2fs.h   |  1 +
> > > > > >  fs/f2fs/file.c   | 13 ++++++++-----
> > > > > >  fs/f2fs/inline.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++-----
> > > > > >  3 files changed, 61 insertions(+), 10 deletions(-)
> > > > > >
> > > > > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > > > > > index 511d6cd..55dbbe7 100644
> > > > > > --- a/fs/f2fs/f2fs.h
> > > > > > +++ b/fs/f2fs/f2fs.h
> > > > > > @@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
> > > > > >   */
> > > > > >  bool f2fs_may_inline(struct inode *);
> > > > > >  void read_inline_data(struct page *, struct page *);
> > > > > > +int truncate_inline_data(struct inode *, u64 from);
> > > > > >  int f2fs_read_inline_data(struct inode *, struct page *);
> > > > > >  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
> > > > > >  int f2fs_convert_inline_inode(struct inode *);
> > > > > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > > > > > index f1341c7..6c4443e 100644
> > > > > > --- a/fs/f2fs/file.c
> > > > > > +++ b/fs/f2fs/file.c
> > > > > > @@ -461,6 +461,9 @@ static int truncate_partial_data_page(struct inode *inode, u64
> from)
> > > > > >  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
> > > > > >  	struct page *page;
> > > > > >
> > > > > > +	if (f2fs_has_inline_data(inode))
> > > > > > +		return 0;
> > > > > > +
> > > > > >  	if (!offset)
> > > > > >  		return 0;
> > > > > >
> > > > > > @@ -497,14 +500,14 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> > > > > >  	if (lock)
> > > > > >  		f2fs_lock_op(sbi);
> > > > > >
> > > > > > -	ipage = get_node_page(sbi, inode->i_ino);
> > > > > > -	if (IS_ERR(ipage)) {
> > > > > > -		err = PTR_ERR(ipage);
> > > > > > +	if (f2fs_has_inline_data(inode)) {
> > > > > > +		err = truncate_inline_data(inode, from);
> > > > > >  		goto out;
> > > > > >  	}
> > > > > >
> > > > > > -	if (f2fs_has_inline_data(inode)) {
> > > > > > -		f2fs_put_page(ipage, 1);
> > > > > > +	ipage = get_node_page(sbi, inode->i_ino);
> > > > > > +	if (IS_ERR(ipage)) {
> > > > > > +		err = PTR_ERR(ipage);
> > > > > >  		goto out;
> > > > > >  	}
> > > > > >
> > > > > > diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
> > > > > > index 4ba9732..a8189c92 100644
> > > > > > --- a/fs/f2fs/inline.c
> > > > > > +++ b/fs/f2fs/inline.c
> > > > > > @@ -50,10 +50,57 @@ void read_inline_data(struct page *page, struct page *ipage)
> > > > > >  	SetPageUptodate(page);
> > > > > >  }
> > > > > >
> > > > > > -static void truncate_inline_data(struct page *ipage)
> > > > > > +static void truncate_inline_inode(struct page *ipage, u64 from)
> > > > > >  {
> > > > > > +	void *addr = inline_data_addr(ipage);
> > > > > > +
> > > > > >  	f2fs_wait_on_page_writeback(ipage, NODE);
> > > > > > -	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
> > > > > > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> > > > > > +}
> > > > > > +
> > > > > > +int truncate_inline_data(struct inode *inode, u64 from)
> > > > > > +{
> > > > > > +	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> > > > > > +	struct page *page, *ipage;
> > > > > > +	void *addr;
> > > > > > +	int err = 0;
> > > > > > +
> > > > > > +	/*
> > > > > > +	 * we should never truncate inline data past max inline data size,
> > > > > > +	 * because we always convert inline inode to normal one before
> > > > > > +	 * truncating real data if new size is past max inline data size.
> > > > > > +	 */
> > > > > > +	f2fs_bug_on(sbi, from > MAX_INLINE_DATA);
> > > > > > +
> > > > > > +	if (from == MAX_INLINE_DATA)
> > > > > > +		return 0;
> > > > > > +
> > > > > > +	page = grab_cache_page(inode->i_mapping, 0);
> > > > > > +	if (!page)
> > > > > > +		return -ENOMEM;
> > > > >
> > > > > Do we need to grab and read #0 page?
> > > >
> > > > No need to read #0 page, sorry for the mistake.
> > > >
> > > > > How about checking its cached page after on-disk truncation?
> > > > >
> > > > > 1. page = get_node_page()
> > > > > 2. check_inline
> > > > > 3. truncate_inline_inode
> > > > > 4. f2fs_put_page(ipage)
> > > > >
> > > > > 5. truncate_partial_data_page(inode, from, force)
> > > > > 	if (!offset && !force)
> > > > >  		return 0;
> > > > >
> > > > > > +
> > > > > > +	ipage = get_node_page(sbi, inode->i_ino);
> > > > > > +	if (IS_ERR(ipage)) {
> > > > > > +		err = PTR_ERR(ipage);
> > > > > > +		goto out;
> > > > > > +	}
> > > > > > +
> > > > > > +	if (!f2fs_has_inline_data(inode)) {
> > > > > > +		f2fs_put_page(ipage, 1);
> > > > > > +		goto out;
> > > > > > +	}
> > > > > > +
> > > > > > +	truncate_inline_inode(ipage, from);
> > > > > > +	set_page_dirty(ipage);
> > > > > > +
> > > > > > +	read_inline_data(page, ipage);
> > > > > > +	f2fs_put_page(ipage, 1);
> > > > > > +
> > > > > > +	addr = inline_data_addr(page);
> > > > > > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> > > > >
> > > > > It needs to do likewise truncate_partial_data_page.
> > > >
> > > > Do you mean like this?
> > >
> > > I meant this.
> > >
> > > Anyway, I also wrote a patch about your testing scenario wrt inline_data.
> > > So, let me submit the patch sooner or later to xfstests mailing list.
> >
> > Sounds good! :)
> >
> > >
> > > Thanks,
> > >
> > > ---
> > >  fs/f2fs/f2fs.h   |  1 +
> > >  fs/f2fs/file.c   | 10 +++++++---
> > >  fs/f2fs/inline.c | 12 +++++++-----
> > >  3 files changed, 15 insertions(+), 8 deletions(-)
> > >
> > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > > index 31b440e..b222b3a 100644
> > > --- a/fs/f2fs/f2fs.h
> > > +++ b/fs/f2fs/f2fs.h
> > > @@ -1760,6 +1760,7 @@ extern struct kmem_cache *inode_entry_slab;
> > >   */
> > >  bool f2fs_may_inline(struct inode *);
> > >  void read_inline_data(struct page *, struct page *);
> > > +void truncate_inline_inode(struct page *, u64);
> > >  int f2fs_read_inline_data(struct inode *, struct page *);
> > >  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
> > >  int f2fs_convert_inline_inode(struct inode *);
> > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > > index f1341c7..ab249dd 100644
> > > --- a/fs/f2fs/file.c
> > > +++ b/fs/f2fs/file.c
> > > @@ -456,12 +456,12 @@ void truncate_data_blocks(struct dnode_of_data *dn)
> > >  	truncate_data_blocks_range(dn, ADDRS_PER_BLOCK);
> > >  }
> > >
> > > -static int truncate_partial_data_page(struct inode *inode, u64 from)
> > > +static int truncate_partial_data_page(struct inode *inode, u64 from, bool force)
> > >  {
> > >  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
> > >  	struct page *page;
> > >
> > > -	if (!offset)
> > > +	if (!offset && !force)
> >
> > We truncate on-disk inode page and #0 page separately, so IMO there is a very
> > small chance the following issue will occur.
> >
> > (0 < truncated_size < MAX_INLINE_SIZE)
> > ->f2fs_setattr
> >   ->truncate_setsize #0 page has been truncated partially
> >   ->f2fs_truncate
> >     ->truncate_blocks
> > 					invalidate #0 page by reclaimer
> > 					update #0 page with original data in inode page by reader
> 
> 					truncate_setsize called truncate_pagesize.
> 					so #0 page was truncated successfully.

Yeah, but it's partially truncating as 0 < truncated_size < MAX_INLINE_SIZE,
After truncating, we still keep [0, truncated_size) valid data in #0 page, and
our #0 page status is uptodate | !dirty.

So what I mean is that mm can reclaim this #0 page, then if someone else read
the #0 page again, we will update the #0 page with original data in inode page
since inode page haven't truncated yet.

If this happened, if we don't truncate #0 page in following code of truncate_blocks,
we will remain the original data for user, it's wrong.

IMO, it's better to truncate inode page and #0 page together, or truncate #0 page
in truncate_partial_data_page.

How do you think?

> 
> >       ->truncate_inline_inode
> >       ->truncate_partial_data_page
> >         we will fail to truncate #0 page because we can't find valid blkaddr for
> >         #0 page in find_data_page(,,false)
> >
> > How about using find_data_page(,,true) to check weather this page is update or not
> > for this condition.
> 
> Oh, I realized that we don't need to call truncate_partial_data_page, since the
> cached #0 page was truncated already. We don't care about that.

IMO, we should care about this #0 page if above example can happen.

> So, do we need to add just truncate_inline_inode() like below?
> 
> >
> > >  		return 0;
> > >
> > >  	page = find_data_page(inode, from >> PAGE_CACHE_SHIFT, false);
> > > @@ -489,6 +489,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> > >  	pgoff_t free_from;
> > >  	int count = 0, err = 0;
> > >  	struct page *ipage;
> > > +	bool truncate_page = false;
> > >
> > >  	trace_f2fs_truncate_blocks_enter(inode, from);
> > >
> > > @@ -504,6 +505,9 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> > >  	}
> > >
> > >  	if (f2fs_has_inline_data(inode)) {
> > > +		truncate_inline_inode(ipage, from);
> > > +		set_page_dirty(ipage);
> >
> > If @from is the same as MAX_INLINE_DATA, we will change nothing in inode page,
> > How about skipping set_page_dirty for inode page in this condition?
> 
> Agreed.
> How about adding this in truncate_inline_inode?
> 
> 	if (from >= MAX_INLINE_DATA)
> 		return;
> 	...
> 	set_page_dirty(ipage);

Yeah, that's good.
 
And What I suggest is:

bool truncate_inline_inode(struct page *ipage, u64 from)
{
	/*
	 * we should never truncate inline data past max inline data size,
	 * because we always convert inline inode to normal one before
	 * truncating real data if new size is past max inline data size.
	 */
	f2fs_bug_on(F2FS_P_SB(ipage), from > MAX_INLINE_DATA);

	if (from == MAX_INLINE_DATA)
		return false;
	...
	return true;
}

in truncate_blocks()

 	if (f2fs_has_inline_data(inode)) {
		if (truncate_inline_inode(ipage, from))
			set_page_dirty(ipage);

So by this way, we can distinguish between a bug and invalid truncating in
truncate_inline_inode, and also we can avoid unneeded set_dirty_page for inode
page in other call path.

How do you think of this?

> 
> Thanks,
> 
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> ---
>  fs/f2fs/f2fs.h   |  1 +
>  fs/f2fs/file.c   |  1 +
>  fs/f2fs/inline.c | 16 +++++++++++-----
>  3 files changed, 13 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 511d6cd..5cd3a2f 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
>   */
>  bool f2fs_may_inline(struct inode *);
>  void read_inline_data(struct page *, struct page *);
> +void truncate_inline_inode(struct page *, u64);
>  int f2fs_read_inline_data(struct inode *, struct page *);
>  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
>  int f2fs_convert_inline_inode(struct inode *);
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index f1341c7..b6b6a04 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -504,6 +504,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
>  	}
> 
>  	if (f2fs_has_inline_data(inode)) {
> +		truncate_inline_inode(ipage, from);
>  		f2fs_put_page(ipage, 1);
>  		goto out;
>  	}
> diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
> index 4ba9732..40bbf96 100644
> --- a/fs/f2fs/inline.c
> +++ b/fs/f2fs/inline.c
> @@ -50,10 +50,16 @@ void read_inline_data(struct page *page, struct page *ipage)
>  	SetPageUptodate(page);
>  }
> 
> -static void truncate_inline_data(struct page *ipage)
> +void truncate_inline_inode(struct page *ipage, u64 from)
>  {
> +	void *addr = inline_data_addr(ipage);
> +
> +	if (from >= MAX_INLIE_DATA)
> +		return;
> +
>  	f2fs_wait_on_page_writeback(ipage, NODE);
> -	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
> +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> +	set_page_dirty(ipage);
>  }
> 
>  int f2fs_read_inline_data(struct inode *inode, struct page *page)
> @@ -131,7 +137,7 @@ no_update:
>  	set_inode_flag(F2FS_I(dn->inode), FI_APPEND_WRITE);
> 
>  	/* clear inline data and flag after data writeback */
> -	truncate_inline_data(dn->inode_page);
> +	truncate_inline_inode(dn->inode_page, 0);
>  clear_out:
>  	stat_dec_inline_inode(dn->inode);
>  	f2fs_clear_inline_inode(dn->inode);
> @@ -245,7 +251,7 @@ process_inline:
>  	if (f2fs_has_inline_data(inode)) {
>  		ipage = get_node_page(sbi, inode->i_ino);
>  		f2fs_bug_on(sbi, IS_ERR(ipage));
> -		truncate_inline_data(ipage);
> +		truncate_inline_inode(ipage, 0);
>  		f2fs_clear_inline_inode(inode);
>  		update_inode(inode, ipage);
>  		f2fs_put_page(ipage, 1);
> @@ -363,7 +369,7 @@ static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
>  	set_page_dirty(page);
> 
>  	/* clear inline dir and flag after data writeback */
> -	truncate_inline_data(ipage);
> +	truncate_inline_inode(ipage, 0);
> 
>  	stat_dec_inline_dir(dir);
>  	clear_inode_flag(F2FS_I(dir), FI_INLINE_DENTRY);
> --
> 2.1.1

Re: [PATCH] f2fs: fix to truncate inline data past EOF

[Jaegeuk Kim]

Hi Chao,

On Tue, Mar 10, 2015 at 10:02:46AM +0800, Chao Yu wrote:
> Hi Jaegeuk,
> 

[snip]

> > > > +static int truncate_partial_data_page(struct inode *inode, u64 from, bool force)
> > > >  {
> > > >  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
> > > >  	struct page *page;
> > > >
> > > > -	if (!offset)
> > > > +	if (!offset && !force)
> > >
> > > We truncate on-disk inode page and #0 page separately, so IMO there is a very
> > > small chance the following issue will occur.
> > >
> > > (0 < truncated_size < MAX_INLINE_SIZE)
> > > ->f2fs_setattr
> > >   ->truncate_setsize #0 page has been truncated partially
> > >   ->f2fs_truncate
> > >     ->truncate_blocks
> > > 					invalidate #0 page by reclaimer
> > > 					update #0 page with original data in inode page by reader
> > 
> > 					truncate_setsize called truncate_pagesize.
> > 					so #0 page was truncated successfully.
> 
> Yeah, but it's partially truncating as 0 < truncated_size < MAX_INLINE_SIZE,
> After truncating, we still keep [0, truncated_size) valid data in #0 page, and
> our #0 page status is uptodate | !dirty.
> 
> So what I mean is that mm can reclaim this #0 page, then if someone else read
> the #0 page again, we will update the #0 page with original data in inode page
> since inode page haven't truncated yet.

The truncate_blocks dropped inline_data in inode page, which is modified by
this patch.
And, the cached #0 page was truncated by truncate_setsize.
Even if this page was evicted and reloaded again, the data would be filled with
the inode page having truncated inline_data.
So, it seems there is no problem.

BTW, do you mean like this scenario?

-> f2fs_setattr
 ->truncate_setsize: #0 page has been truncated partially
 ->f2fs_truncate
 					invalidate #0 page by reclaimer
 					update #0 page with original data in inode page by reader

    ->truncate_blocks
      (*)-> truncate_inline_inode
    (*)-> truncate_partial_data_page(,, force)
       find_data_page(,, force)  <- we can use *force* here.

Then, I agree that two functions as noted (*) above would be necessary.

> 
> If this happened, if we don't truncate #0 page in following code of truncate_blocks,
> we will remain the original data for user, it's wrong.
> 
> IMO, it's better to truncate inode page and #0 page together, or truncate #0 page
> in truncate_partial_data_page.
> 
> How do you think?
> 
> > 
> > >       ->truncate_inline_inode
> > >       ->truncate_partial_data_page
> > >         we will fail to truncate #0 page because we can't find valid blkaddr for
> > >         #0 page in find_data_page(,,false)
> > >
> > > How about using find_data_page(,,true) to check weather this page is update or not
> > > for this condition.
> > 
> > Oh, I realized that we don't need to call truncate_partial_data_page, since the
> > cached #0 page was truncated already. We don't care about that.
> 
> IMO, we should care about this #0 page if above example can happen.
> 
> > So, do we need to add just truncate_inline_inode() like below?
> > 
> > >
> > > >  		return 0;
> > > >
> > > >  	page = find_data_page(inode, from >> PAGE_CACHE_SHIFT, false);
> > > > @@ -489,6 +489,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> > > >  	pgoff_t free_from;
> > > >  	int count = 0, err = 0;
> > > >  	struct page *ipage;
> > > > +	bool truncate_page = false;
> > > >
> > > >  	trace_f2fs_truncate_blocks_enter(inode, from);
> > > >
> > > > @@ -504,6 +505,9 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> > > >  	}
> > > >
> > > >  	if (f2fs_has_inline_data(inode)) {
> > > > +		truncate_inline_inode(ipage, from);
> > > > +		set_page_dirty(ipage);
> > >
> > > If @from is the same as MAX_INLINE_DATA, we will change nothing in inode page,
> > > How about skipping set_page_dirty for inode page in this condition?
> > 
> > Agreed.
> > How about adding this in truncate_inline_inode?
> > 
> > 	if (from >= MAX_INLINE_DATA)
> > 		return;
> > 	...
> > 	set_page_dirty(ipage);
> 
> Yeah, that's good.
>  
> And What I suggest is:
> 
> bool truncate_inline_inode(struct page *ipage, u64 from)
> {
> 	/*
> 	 * we should never truncate inline data past max inline data size,
> 	 * because we always convert inline inode to normal one before
> 	 * truncating real data if new size is past max inline data size.
> 	 */
> 	f2fs_bug_on(F2FS_P_SB(ipage), from > MAX_INLINE_DATA);
> 
> 	if (from == MAX_INLINE_DATA)

	if (from >= MAX_INLINE_DATA)  to handle when f2fs_bug_on is bypassed.

> 		return false;
> 	...
> 	return true;
> }
> 
> in truncate_blocks()
> 
>  	if (f2fs_has_inline_data(inode)) {
> 		if (truncate_inline_inode(ipage, from))
> 			set_page_dirty(ipage);
> 
> So by this way, we can distinguish between a bug and invalid truncating in
> truncate_inline_inode, and also we can avoid unneeded set_dirty_page for inode
> page in other call path.

Ok, it's not a big deal.

Thanks,

> 
> How do you think of this?
> 
> > 
> > Thanks,
> > 
> > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> > ---
> >  fs/f2fs/f2fs.h   |  1 +
> >  fs/f2fs/file.c   |  1 +
> >  fs/f2fs/inline.c | 16 +++++++++++-----
> >  3 files changed, 13 insertions(+), 5 deletions(-)
> > 
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index 511d6cd..5cd3a2f 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -1754,6 +1754,7 @@ extern struct kmem_cache *inode_entry_slab;
> >   */
> >  bool f2fs_may_inline(struct inode *);
> >  void read_inline_data(struct page *, struct page *);
> > +void truncate_inline_inode(struct page *, u64);
> >  int f2fs_read_inline_data(struct inode *, struct page *);
> >  int f2fs_convert_inline_page(struct dnode_of_data *, struct page *);
> >  int f2fs_convert_inline_inode(struct inode *);
> > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > index f1341c7..b6b6a04 100644
> > --- a/fs/f2fs/file.c
> > +++ b/fs/f2fs/file.c
> > @@ -504,6 +504,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> >  	}
> > 
> >  	if (f2fs_has_inline_data(inode)) {
> > +		truncate_inline_inode(ipage, from);
> >  		f2fs_put_page(ipage, 1);
> >  		goto out;
> >  	}
> > diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
> > index 4ba9732..40bbf96 100644
> > --- a/fs/f2fs/inline.c
> > +++ b/fs/f2fs/inline.c
> > @@ -50,10 +50,16 @@ void read_inline_data(struct page *page, struct page *ipage)
> >  	SetPageUptodate(page);
> >  }
> > 
> > -static void truncate_inline_data(struct page *ipage)
> > +void truncate_inline_inode(struct page *ipage, u64 from)
> >  {
> > +	void *addr = inline_data_addr(ipage);
> > +
> > +	if (from >= MAX_INLIE_DATA)
> > +		return;
> > +
> >  	f2fs_wait_on_page_writeback(ipage, NODE);
> > -	memset(inline_data_addr(ipage), 0, MAX_INLINE_DATA);
> > +	memset(addr + from, 0, MAX_INLINE_DATA - from);
> > +	set_page_dirty(ipage);
> >  }
> > 
> >  int f2fs_read_inline_data(struct inode *inode, struct page *page)
> > @@ -131,7 +137,7 @@ no_update:
> >  	set_inode_flag(F2FS_I(dn->inode), FI_APPEND_WRITE);
> > 
> >  	/* clear inline data and flag after data writeback */
> > -	truncate_inline_data(dn->inode_page);
> > +	truncate_inline_inode(dn->inode_page, 0);
> >  clear_out:
> >  	stat_dec_inline_inode(dn->inode);
> >  	f2fs_clear_inline_inode(dn->inode);
> > @@ -245,7 +251,7 @@ process_inline:
> >  	if (f2fs_has_inline_data(inode)) {
> >  		ipage = get_node_page(sbi, inode->i_ino);
> >  		f2fs_bug_on(sbi, IS_ERR(ipage));
> > -		truncate_inline_data(ipage);
> > +		truncate_inline_inode(ipage, 0);
> >  		f2fs_clear_inline_inode(inode);
> >  		update_inode(inode, ipage);
> >  		f2fs_put_page(ipage, 1);
> > @@ -363,7 +369,7 @@ static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
> >  	set_page_dirty(page);
> > 
> >  	/* clear inline dir and flag after data writeback */
> > -	truncate_inline_data(ipage);
> > +	truncate_inline_inode(ipage, 0);
> > 
> >  	stat_dec_inline_dir(dir);
> >  	clear_inode_flag(F2FS_I(dir), FI_INLINE_DENTRY);
> > --
> > 2.1.1

RE: [PATCH] f2fs: fix to truncate inline data past EOF

[Chao Yu]

Hi Jaegeuk,

> -----Original Message-----
> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> Sent: Tuesday, March 10, 2015 11:00 AM
> To: Chao Yu
> Cc: 'Changman Lee'; linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH] f2fs: fix to truncate inline data past EOF
> 
> Hi Chao,
> 
> On Tue, Mar 10, 2015 at 10:02:46AM +0800, Chao Yu wrote:
> > Hi Jaegeuk,
> >
> 
> [snip]
> 
> > > > > +static int truncate_partial_data_page(struct inode *inode, u64 from, bool force)
> > > > >  {
> > > > >  	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
> > > > >  	struct page *page;
> > > > >
> > > > > -	if (!offset)
> > > > > +	if (!offset && !force)
> > > >
> > > > We truncate on-disk inode page and #0 page separately, so IMO there is a very
> > > > small chance the following issue will occur.
> > > >
> > > > (0 < truncated_size < MAX_INLINE_SIZE)
> > > > ->f2fs_setattr
> > > >   ->truncate_setsize #0 page has been truncated partially
> > > >   ->f2fs_truncate
> > > >     ->truncate_blocks
> > > > 					invalidate #0 page by reclaimer
> > > > 					update #0 page with original data in inode page by reader
> > >
> > > 					truncate_setsize called truncate_pagesize.
> > > 					so #0 page was truncated successfully.
> >
> > Yeah, but it's partially truncating as 0 < truncated_size < MAX_INLINE_SIZE,
> > After truncating, we still keep [0, truncated_size) valid data in #0 page, and
> > our #0 page status is uptodate | !dirty.
> >
> > So what I mean is that mm can reclaim this #0 page, then if someone else read
> > the #0 page again, we will update the #0 page with original data in inode page
> > since inode page haven't truncated yet.
> 
> The truncate_blocks dropped inline_data in inode page, which is modified by
> this patch.
> And, the cached #0 page was truncated by truncate_setsize.
> Even if this page was evicted and reloaded again, the data would be filled with
> the inode page having truncated inline_data.
> So, it seems there is no problem.
> 
> BTW, do you mean like this scenario?

Yeah, actually it is. ;-)

> 
> -> f2fs_setattr
>  ->truncate_setsize: #0 page has been truncated partially
>  ->f2fs_truncate
>  					invalidate #0 page by reclaimer
>  					update #0 page with original data in inode page by reader
> 
>     ->truncate_blocks
>       (*)-> truncate_inline_inode
>     (*)-> truncate_partial_data_page(,, force)
>        find_data_page(,, force)  <- we can use *force* here.
> 
> Then, I agree that two functions as noted (*) above would be necessary.
> 
> >
> > If this happened, if we don't truncate #0 page in following code of truncate_blocks,
> > we will remain the original data for user, it's wrong.
> >
> > IMO, it's better to truncate inode page and #0 page together, or truncate #0 page
> > in truncate_partial_data_page.
> >
> > How do you think?
> >
> > >
> > > >       ->truncate_inline_inode
> > > >       ->truncate_partial_data_page
> > > >         we will fail to truncate #0 page because we can't find valid blkaddr for
> > > >         #0 page in find_data_page(,,false)
> > > >
> > > > How about using find_data_page(,,true) to check weather this page is update or not
> > > > for this condition.
> > >
> > > Oh, I realized that we don't need to call truncate_partial_data_page, since the
> > > cached #0 page was truncated already. We don't care about that.
> >
> > IMO, we should care about this #0 page if above example can happen.
> >
> > > So, do we need to add just truncate_inline_inode() like below?
> > >
> > > >
> > > > >  		return 0;
> > > > >
> > > > >  	page = find_data_page(inode, from >> PAGE_CACHE_SHIFT, false);
> > > > > @@ -489,6 +489,7 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> > > > >  	pgoff_t free_from;
> > > > >  	int count = 0, err = 0;
> > > > >  	struct page *ipage;
> > > > > +	bool truncate_page = false;
> > > > >
> > > > >  	trace_f2fs_truncate_blocks_enter(inode, from);
> > > > >
> > > > > @@ -504,6 +505,9 @@ int truncate_blocks(struct inode *inode, u64 from, bool lock)
> > > > >  	}
> > > > >
> > > > >  	if (f2fs_has_inline_data(inode)) {
> > > > > +		truncate_inline_inode(ipage, from);
> > > > > +		set_page_dirty(ipage);
> > > >
> > > > If @from is the same as MAX_INLINE_DATA, we will change nothing in inode page,
> > > > How about skipping set_page_dirty for inode page in this condition?
> > >
> > > Agreed.
> > > How about adding this in truncate_inline_inode?
> > >
> > > 	if (from >= MAX_INLINE_DATA)
> > > 		return;
> > > 	...
> > > 	set_page_dirty(ipage);
> >
> > Yeah, that's good.
> >
> > And What I suggest is:
> >
> > bool truncate_inline_inode(struct page *ipage, u64 from)
> > {
> > 	/*
> > 	 * we should never truncate inline data past max inline data size,
> > 	 * because we always convert inline inode to normal one before
> > 	 * truncating real data if new size is past max inline data size.
> > 	 */
> > 	f2fs_bug_on(F2FS_P_SB(ipage), from > MAX_INLINE_DATA);
> >
> > 	if (from == MAX_INLINE_DATA)
> 
> 	if (from >= MAX_INLINE_DATA)  to handle when f2fs_bug_on is bypassed.

Agreed, we should handle this condition.

> 
> > 		return false;
> > 	...
> > 	return true;
> > }
> >
> > in truncate_blocks()
> >
> >  	if (f2fs_has_inline_data(inode)) {
> > 		if (truncate_inline_inode(ipage, from))
> > 			set_page_dirty(ipage);
> >
> > So by this way, we can distinguish between a bug and invalid truncating in
> > truncate_inline_inode, and also we can avoid unneeded set_dirty_page for inode
> > page in other call path.
> 
> Ok, it's not a big deal.

Thanks for your help! Let me send a v2 patch.

Regards,
Chao

[sinp]