Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Not all architectures (in particular, sparc64) have empty_zero_page.
So instead of copying from empty_zero_page, use memset to clear the
inline data by signalling to ext4_xattr_set_entry() via a magic
pointer value, EXT4_ZERO_ATTR_VALUE, which is defined by casting -1 to
a pointer.

This fixes a build failure on sparc64, and the memset() should be more
efficient than using memcpy() anyway.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

If we are punching hole in a file, we will return ENOTSUPP.
As for the fallocation of some extents, we will convert the
inline data to a normal extent based file first.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Signed-off-by: NRobin Dong <sanbai@taobao.com>
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Now we that store data in the inode, in case we need to store some
xattrs and inode doesn't have enough space, Andreas suggested that we
should keep the xattr(metadata) in and data should be pushed out.  So
this patch does the work.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

fiemap is used to find the disk layout of a file, as for inline data,
let us just pretend like a file with just one extent.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

In case we rename a directory, ext4_rename has to read the dir block
and change its dotdot's information.  The old ext4_rename encapsulated
the dir_block read into itself.  So this patch adds a new function
ext4_get_first_dir_block() which gets the dir buffer information so
the ext4_rename can handle it properly.  As it will also change the
parent inode number, we return the parent_de so that ext4_rename() can
handle it more easily.

ext4_find_entry is also changed so that the caller(rename) can tell
whether the found entry is an inlined one or not and journaling the
corresponding buffer head.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

empty_dir is used when deleting a dir.  So it should handle inline dir
properly.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Create a new function ext4_find_inline_entry() to handle the case of
inline data.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

For "." and "..", we just call filldir by ourselves
instead of iterating the real dir entry.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

This patch let add_dir_entry handle the inline data case. So the
dir is initialized as inline dir first and then we can try to add
some files to it, when the inline space can't hold all the entries,
a dir block will be created and the dir entry will be moved to it.

Also for an inlined dir, "." and ".." are removed and we only use
4 bytes to store the parent inode number. These 2 entries will be
added when we convert an inline dir to a block-based one.

[ Folded in patch from Dan Carpenter to remove an unused variable. ]
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

For delayed allocation mode, we write to inline data if the file
is small enough. And in case of we write to some offset larger
than the inline size, the 1st page is dirtied, so that
ext4_da_writepages can handle the conversion. When the 1st page
is initialized with blocks, the inline part is removed.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

For a normal write case (not journalled write, not delayed
allocation), we write to the inline if the file is small and convert
it to an extent based file when the write is larger than the max
inline size.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Let readpage and readpages handle the case when we want to read an
inlined file.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Implement inline data with xattr.

Now we use "system.data" to store xattr, and the xattr will
be extended if the i_size is increased while we don't release
the space during truncate.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>