fs/ntfs3: Code formatting

clang-format-15 was used to format code according kernel's .clang-format.

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

fs/ntfs3: Code formatting and refactoring

Added minor refactoring.
Added and fixed some comments.
In some places, the code has been reformatted to fit into 80 columns.
clang-format-12 was used to format code according kernel's .clang-format.

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

fs/ntfs3: Remove tabs before spaces from comment

Remove tabs before spaces from comment as recommended by kernel coding
style. Checkpatch also warn about these.

Signed-off-by: Kari Argillander <kari.argillander@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

fs/ntfs3: Change right headers to lznt.c

There is lot of headers which we do not need in this file. Delete them
and add what we really need. Here is list which identify why we need
this header.

<linux/kernel.h> // min()
<linux/slab.h> // kzalloc()
<linux/stddef.h> // offsetof()
<linux/string.h> // memcpy(), memset()
<linux/types.h> // u8, size_t, etc.

"debug.h" // PtrOffset()

Signed-off-by: Kari Argillander <kari.argillander@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

fs/ntfs3: Restyle comments to better align with kernel-doc

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

fs/ntfs3: Restyle comments to better align with kernel-doc

Capitalize comments and end with period for better reading.

Also function comments are now little more kernel-doc style. This way we
can easily convert them to kernel-doc style if we want. Note that these
are not yet complete with this style. Example function comments start
with /* and in kernel-doc style they start /**.

Use imperative mood in function descriptions.

Change words like ntfs -> NTFS, linux -> Linux.

Use "we" not "I" when commenting code.

Signed-off-by: Kari Argillander <kari.argillander@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

fs/ntfs3: Do not use driver own alloc wrappers

Problem with these wrapper is that we cannot take off example GFP_NOFS
flag. It is not recomended use those in all places. Also if we change
one driver specific wrapper to kernel wrapper then it would look really
weird. People should be most familiar with kernel wrappers so let's just
use those ones.

Driver specific alloc wrapper also confuse some static analyzing tools,
good example is example kernels checkpatch tool. After we converter
these to kernel specific then warnings is showed.

Following Coccinelle script was used to automate changing.

virtual patch

@alloc depends on patch@
expression x;
expression y;
@@
(
- ntfs_malloc(x)
+ kmalloc(x, GFP_NOFS)
|
- ntfs_zalloc(x)
+ kzalloc(x, GFP_NOFS)
|
- ntfs_vmalloc(x)
+ kvmalloc(x, GFP_NOFS)
|
- ntfs_free(x)
+ kfree(x)
|
- ntfs_vfree(x)
+ kvfree(x)
|
- ntfs_memdup(x, y)
+ kmemdup(x, y, GFP_NOFS)
)

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kari Argillander <kari.argillander@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

fs/ntfs3: Add compression

This patch adds different types of NTFS-applicable compressions:
- lznt
- lzx
- xpress
Latter two (lzx, xpress) implement Windows Compact OS feature and
were taken from ntfs-3g system comression plugin authored by Eric Biggers
(https://github.com/ebiggers/ntfs-3g-system-compression)
which were ported to ntfs3 and adapted to Linux Kernel environment.

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>