| Message ID | 1346391419-4278-2-git-send-email-bo.li.liu@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Aug 31, 2012 at 01:36:54PM +0800, Liu Bo wrote: > The new created file should not only inherit the NODATACOW flag, but also > honor NODATASUM flag, because we must do COW on a file extent with checksum. I was not entierly correct when suggesting to move NODATASUM to inherit_iflags. Se below. > > Signed-off-by: Liu Bo <bo.li.liu@oracle.com> > --- > fs/btrfs/inode.c | 3 +-- > fs/btrfs/ioctl.c | 3 ++- > 2 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index b2c3514..9bce6e9 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -4720,8 +4720,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, > if (S_ISREG(mode)) { Originaly it applied to regular files only. > if (btrfs_test_opt(root, NODATASUM)) > BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; > - if (btrfs_test_opt(root, NODATACOW) || > - (BTRFS_I(dir)->flags & BTRFS_INODE_NODATACOW)) > + if (btrfs_test_opt(root, NODATACOW)) > BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; > } > > diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c > index 00ddf22..7390b25 100644 > --- a/fs/btrfs/ioctl.c > +++ b/fs/btrfs/ioctl.c > @@ -141,7 +141,8 @@ void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) > } > > if (flags & BTRFS_INODE_NODATACOW) > - BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; > + BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW | > + BTRFS_INODE_NODATASUM; But now this will happen to: * nodes (mknod) * directories -- NODATASUM for a dir does nothing, but does not feel right * symlinks -- same * subvolume roots -- same, and even more confusing what it does While the fix you suggested in http://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg18292.html is simple, I'm still inclined to keep all flag inheritance at one place, so the fix I'm proposing is to do > if (flags & BTRFS_INODE_NODATACOW) > BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; if (S_ISREG(inode->i_mode)) BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; } > > btrfs_update_iflags(inode); > } -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index b2c3514..9bce6e9 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -4720,8 +4720,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, if (S_ISREG(mode)) { if (btrfs_test_opt(root, NODATASUM)) BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; - if (btrfs_test_opt(root, NODATACOW) || - (BTRFS_I(dir)->flags & BTRFS_INODE_NODATACOW)) + if (btrfs_test_opt(root, NODATACOW)) BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; } diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 00ddf22..7390b25 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -141,7 +141,8 @@ void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) } if (flags & BTRFS_INODE_NODATACOW) - BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; + BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW | + BTRFS_INODE_NODATASUM; btrfs_update_iflags(inode); }
Users report a bug, the reproducer is: $ mkfs.btrfs /dev/loop0 $ mount /dev/loop0 /mnt/btrfs/ $ mkdir /mnt/btrfs/dir $ chattr +C /mnt/btrfs/dir/ $ dd if=/dev/zero of=/mnt/btrfs/dir/foo bs=4K count=10; $ lsattr /mnt/btrfs/dir/foo ---------------C- /mnt/btrfs/dir/foo $ filefrag /mnt/btrfs/dir/foo /mnt/btrfs/dir/foo: 1 extent found ---> an extent $ dd if=/dev/zero of=/mnt/btrfs/dir/foo bs=4K count=1 seek=5 conv=notrunc,nocreat; sync $ filefrag /mnt/btrfs/dir/foo /mnt/btrfs/dir/foo: 3 extents found ---> with nocow, btrfs breaks the extent into three parts The new created file should not only inherit the NODATACOW flag, but also honor NODATASUM flag, because we must do COW on a file extent with checksum. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> --- fs/btrfs/inode.c | 3 +-- fs/btrfs/ioctl.c | 3 ++- 2 files changed, 3 insertions(+), 3 deletions(-)