On 07/01/2011 03:26 AM, Lukas Czerner wrote:

On Thu, 30 Jun 2011, Allison Henderson wrote:

quoted

The first patch adds a new flag, EXT4_FREE_BLOCKS_ZERO,
to ext4_free_blocks. This flag causes causes blocks to be
zerod before they are freed.  Files that have the EXT4_SECRM_FL
attribute flag on will have their blocks zerod when
they are released.  The EXT4_SECRM_FL attribute flag can
be enabled useing chattr +s

Hi Allison,

the patch looks good, however I have one little nitpick bellow:)

quoted

Signed-off-by: Allison Henderson<redacted>
---
v1->v2
Removed check for discard mount option and replaced with
check for secure discard and discard_zeroes_data

Added BLKDEV_DISCARD_SECURE to the sb_issue_discard call

v2->v3
Removed code for discard.  A seperate patch will
be done to add that code in the block layer

:100644 100644 1921392... 38a4d75... M	fs/ext4/ext4.h
:100644 100644 f815cc8... cf178f3... M	fs/ext4/extents.c
:100644 100644 62f86e7... 8fdae7d... M	fs/ext4/inode.c
:100644 100644 6ed859d... 94872b2... M	fs/ext4/mballoc.c
:100644 100644 c757adc... 1ff7532... M	fs/ext4/xattr.c
  fs/ext4/ext4.h    |    1 +
  fs/ext4/extents.c |    3 +++
  fs/ext4/inode.c   |    3 +++
  fs/ext4/mballoc.c |    8 ++++++++
  fs/ext4/xattr.c   |   12 ++++++++----
  5 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 1921392..38a4d75 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h

@@ -526,6 +526,7 @@ struct ext4_new_group_data {
  #define EXT4_FREE_BLOCKS_METADATA	0x0001
  #define EXT4_FREE_BLOCKS_FORGET		0x0002
  #define EXT4_FREE_BLOCKS_VALIDATED	0x0004
+#define EXT4_FREE_BLOCKS_ZERO		0x0008

  /*
   * ioctl commands

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index f815cc8..cf178f3 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c

@@ -2231,6 +2231,9 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode,

  	if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
  		flags |= EXT4_FREE_BLOCKS_METADATA;
+
+	if (EXT4_I(inode)->i_flags&  EXT4_SECRM_FL)
+		flags |= EXT4_FREE_BLOCKS_ZERO;
  #ifdef EXTENTS_STATS
  	{
  		struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 62f86e7..8fdae7d 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c

@@ -4182,6 +4182,9 @@ static int ext4_clear_blocks(handle_t *handle, struct inode *inode,
  	for (p = first; p<  last; p++)
  		*p = 0;

+	if (EXT4_I(inode)->i_flags&  EXT4_SECRM_FL)
+		flags |= EXT4_FREE_BLOCKS_ZERO;
+
  	ext4_free_blocks(handle, inode, NULL, block_to_free, count, flags);
  	return 0;
  out_err:

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 6ed859d..94872b2 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c

@@ -4485,6 +4485,14 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode,
  	ext4_debug("freeing block %llu\n", block);
  	trace_ext4_free_blocks(inode, block, count, flags);

+	if (flags&  EXT4_FREE_BLOCKS_ZERO) {
+		err = sb_issue_zeroout(inode->i_sb, block, count, GFP_NOFS);
+		if (err<  0)
+			goto error_return;
+		else
+			err = 0;

No need to set err=0. sb_issue_zeroout() will return zero on success.

Thanks!
-Lukas

Ah, alrighty, I will pull that out.  Thx! :)

Allison

quoted

+	}
+
  	if (flags&  EXT4_FREE_BLOCKS_FORGET) {
  		struct buffer_head *tbh = bh;
  		int i;

diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index c757adc..1ff7532 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c

@@ -471,7 +471,7 @@ ext4_xattr_release_block(handle_t *handle, struct inode *inode,
  			 struct buffer_head *bh)
  {
  	struct mb_cache_entry *ce = NULL;
-	int error = 0;
+	int free_blocks_flags, error = 0;

  	ce = mb_cache_entry_get(ext4_xattr_cache, bh->b_bdev, bh->b_blocknr);
  	error = ext4_journal_get_write_access(handle, bh);

@@ -484,9 +484,13 @@ ext4_xattr_release_block(handle_t *handle, struct inode *inode,
  		if (ce)
  			mb_cache_entry_free(ce);
  		get_bh(bh);
-		ext4_free_blocks(handle, inode, bh, 0, 1,
-				 EXT4_FREE_BLOCKS_METADATA |
-				 EXT4_FREE_BLOCKS_FORGET);
+		free_blocks_flags = EXT4_FREE_BLOCKS_METADATA |
+					EXT4_FREE_BLOCKS_FORGET;
+
+		if (EXT4_I(inode)->i_flags&  EXT4_SECRM_FL)
+			free_blocks_flags |= EXT4_FREE_BLOCKS_ZERO;
+
+		ext4_free_blocks(handle, inode, bh, 0, 1, free_blocks_flags);
  	} else {
  		le32_add_cpu(&BHDR(bh)->h_refcount, -1);
  		error = ext4_handle_dirty_metadata(handle, inode, bh);