ksm: check and skip page, if it is already scanned

From: Pradeep Sawlani <sawlani@amazon.com>

On system like Android where most of the process are forked
from parent w/o execve, KSM can scan same page multiple times
in one scan cycle. There is no advantage in scanning same page
multiple times for merging. During testing with Android, it was
observed around 60% pages are skipped for each scan cycle.

Change-Id: I0cf01802f0b4d61fcab92558beb9e1c660dc9a77
Link: http://lkml.kernel.org/r/CAMrOTPgBtANS_ryRjan0-dTL97U7eRvtf3dCsss=Kn+Uk89fuA@mail.gmail.com
Signed-off-by: Pradeep Sawlani <sawlani@amazon.com>

Signed-off-by: Paul Reioux <reioux@gmail.com>
FS: Initial F2FS import

Signed-off-by: Paul Reioux <reioux@gmail.com>
vfs: ignore error on forced remount

On emergency remount we want to force MS_RDONLY on the super block
even if ->remount_fs() failed for some reason.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
hypfs: remove unnecessary nlink setting

alloc_inode() initializes i_nlink to 1.  Remove unnecessary
re-initialization.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
jfs: remove unnecessary nlink setting

alloc_inode() initializes i_nlink to 1.  Remove unnecessary
re-initialization.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
ocfs2: remove unnecessary nlink setting

alloc_inode() initializes i_nlink to 1.  Remove unnecessary
re-initialization.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Joel Becker <jlbec@evilplan.org>
CC: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
logfs: remove unnecessary nlink setting

alloc_inode() initializes i_nlink to 1.  Remove unnecessary
re-initialization.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Joern Engel <joern@logfs.org>
CC: Prasad Joshi <prasadjoshi.linux@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
filesystems: add missing nlink wrappers

Replace direct i_nlink updates with the respective updater function
(inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count).

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
filesystems: add set_nlink()

Replace remaining direct i_nlink updates with a new set_nlink()
updater function.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paul Reioux <reioux@gmail.com>

Conflicts:
	fs/sysfs/inode.c
vfs: protect i_nlink

Prevent direct modification of i_nlink by making it const and adding a
non-const __i_nlink alias.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
vfs: add d_prune dentry operation

This adds a d_prune dentry operation that is called by the VFS prior to
pruning (i.e. unhashing and killing) a hashed dentry from the dcache.
Wrap dentry_lru_del() and use the new _prune() helper in the cases where we
are about to unhash and kill the dentry.

This will be used by Ceph to maintain a flag indicating whether the
complete contents of a directory are contained in the dcache, allowing it
to satisfy lookups and readdir without addition server communication.

Renumber a few DCACHE_* #defines to group DCACHE_OP_PRUNE with the other
DCACHE_OP_ bits.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
vfs: export symbol d_find_any_alias()

Ceph needs this.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sage Weil <sage@newdream.net>
vfs: new helper - d_make_root()

d_alloc_root() with iput() in case of allocation failure...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
f2fs: add code to handle the lack of s_max_links superblock field in 3.2

further modified for Nexus Grouper Kernel

Signed-off-by: Alejandro Martinez Ruiz <alex@nowcomputing.com>
Signed-off-by: Paul Reioux <reioux@gmail.com>
Merge commit '5a2f3a02aea164f4f59c0c3497772090a411b462' into kk_mr1
evm: building without EVM enabled fixes

- Missing 'inline' on evm_inode_setattr() definition.
Introduced by commit 817b54aa45db ("evm: add evm_inode_setattr to prevent
updating an invalid security.evm").

- Missing security_old_inode_init_security() stub function definition.
Caused by commit 9d8f13ba3f48 ("security: new security_inode_init_security
API adds function callback").

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
evm: fix build problems

- Make the previously missing security_old_inode_init_security() stub
  function definition static inline.

- The stub security_inode_init_security() function previously returned
  -EOPNOTSUPP and relied on the callers to change it to 0.  The stub
  security/security_old_inode_init_security() functions now return 0.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
security: Fix a typo

Fix a typo.

Signed-off-by: Roy.Li <rongqing.li@windriver.com>
Signed-off-by: James Morris <jmorris@namei.org>
security: sparse fix: Move security_fixup_op to security.h

Fix sparse warning by moving declaraion to global header.

Signed-off-by: James Morris <jmorris@namei.org>
security.h: fix misc typos/grammar errors in comments

Fix various typos/grammar errors in include/linux/security.h comments (no code changes).

Signed-off-by: Vsevolod Alekseev <vsevolod.alekseev@gmx.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>