[RFC PATCH v2 0/3] UBIFS: add ACL support

[Sheng Yong <shengyong1@huawei.com>]

Hi, folks,
These 3 patches add ACL support for UBIFS.

UBIFS ACL is based on xattr, which simplifies the implementation without
considering budget and sync.

New kernel/mount options, CONFIG_UBIFS_FS_POSIX_ACL and `-o acl', are
introduced to enable or disable UBIFS ACL.

`acl.c' provides format conversion between in-memory ACL and on-flash ACL.
Each time a new inode is created, the correspondng ACL xattr is built
(except for the inode of an xattr dent). 

Testcases (adjusted to mount an UBI volume) in LTP [1] are passed.

Any comment is appreciated. 

V2:
* Do not set ACL-xattr-handler, and call generic ACL handler in xattr
  functions.

V1:
http://lists.infradead.org/pipermail/linux-mtd/2015-March/058452.html

[1] https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/fs/acl/tacl_xattr.sh

thanks,
Sheng

Sheng Yong (3):
  UBIFS: xattr: add generic helper functions for set/get xattr
  UBIFS: ACL: add ACL support
  UBIFS: ACL: add ACL config option

 fs/ubifs/Kconfig  |  11 ++
 fs/ubifs/Makefile |   1 +
 fs/ubifs/acl.c    | 312 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 fs/ubifs/dir.c    |  20 ++++
 fs/ubifs/file.c   |  14 +++
 fs/ubifs/super.c  |  15 +++
 fs/ubifs/ubifs.h  |  18 ++++
 fs/ubifs/xattr.c  | 115 +++++++++++++++-----
 8 files changed, 482 insertions(+), 24 deletions(-)
 create mode 100644 fs/ubifs/acl.c

-- 
1.9.1