switch a bunch of places to mnt_want_write_file()

it's both faster (in case when file has been opened for write) and cleaner.

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

Conflicts:
	fs/nfsd/nfs4recover.c
	fs/xfs/xfs_ioctl.c
switch vfs_mkdir() and ->mkdir() to umode_t

vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...

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

Conflicts:
	fs/affs/affs.h
	fs/cifs/cifsfs.h
	fs/nfs/dir.c
	fs/xfs/xfs_iops.c
	include/linux/fs.h
switch ->create() to umode_t

vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the method

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
ext4: propagate umode_t

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
ext4: add a function which extends a group without checking parameters

This patch added a function named ext4_group_extend_no_check() whose code
is copied from ext4_group_extend().  ext4_group_extend_no_check() assumes
the parameter is valid and has been checked by caller.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: add a function which adds a new group descriptors to a fs

This patch adds a function named ext4_add_new_descs() which adds one
or more new group descriptors to a fs and whose code is copied from
ext4_group_add().

The function will be used by new resize implementation.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: add a structure which will be used by 64bit-resize interface

This patch adds a structure which will be used by 64bit-resize interface.
Two functions which allocate and destroy the structure respectively are
added.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: add a function which sets up group blocks of a flex bg

This patch adds a function named setup_new_flex_group_blocks() which
sets up group blocks of a flex bg.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: add a function which sets up a block group descriptors of a flex bg

This patch adds a function named ext4_setup_new_descs which sets up the
block group descriptors of a flex bg.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: add a function which updates the super block during online resizing

This patch adds a function named ext4_update_super() which updates
super block so the newly created block groups are visible to the file
system.  This code is copied from ext4_group_add().

The function will be used by new resize implementation.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: pass verify_reserved_gdb() the number of group decriptors

The 64bit resizer adds a flex group each time, so verify_reserved_gdb
can not use s_groups_count directly, it should use the number of group
decriptors before the added group.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: add a new function which allocates bitmaps and inode tables

This patch adds a new function named ext4_allocates_group_table()
which allocates block bitmaps, inode bitmaps and inode tables for a
flex groups and is used by resize code.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: add a new function which adds a flex group to a fs

This patch adds a new function named ext4_flex_group_add() which adds a
flex group to a fs.  The function is used by 64bit-resize interface.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: add new online resize interface

This patch adds new online resize interface, whose input argument is a
64-bit integer indicating how many blocks there are in the resized fs.

In new resize impelmentation, all work like allocating group tables
are done by kernel side, so the new resize interface can support
flex_bg feature and prepares ground for suppoting resize with features
like bigalloc and exclude bitmap. Besides these, user-space tools just
passes in the new number of blocks.

We delay initializing the bitmaps and inode tables of added groups if
possible and add multi groups (a flex groups) each time, so new resize
is very fast like mkfs.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: let ext4_group_extend() use common code

ext4_group_extend_no_check() is moved out from ext4_group_extend(),
this patch lets ext4_group_extend() call ext4_group_extentd_no_check()
instead.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: let ext4_group_add() use common code

This patch lets ext4_group_add() call ext4_flex_group_add().

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: add missing ext4_resize_end on error paths

Online resize ioctls 'EXT4_IOC_GROUP_EXTEND' and 'EXT4_IOC_GROUP_ADD'
call ext4_resize_begin() to check permissions and to set the
EXT4_RESIZING bit lock, they do their work and they must finish with
ext4_resize_end() which calls clear_bit_unlock() to unlock and to
avoid -EBUSY errors for the next resize operations.

This patch adds the missing ext4_resize_end() calls on error paths.

Patch tested.

Cc: stable@vger.kernel.org
Signed-off-by: Djalal Harouni <tixxdz@opendz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: Report max_batch_time option correctly

Currently the value reported for max_batch_time is really the
value of min_batch_time.

Reported-by: Russell Coker <russell@coker.com.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ext4: reserve new feature flag codepoints

Reserve the ext4 features flags EXT4_FEATURE_RO_COMPAT_METADATA_CSUM,
EXT4_FEATURE_INCOMPAT_INLINEDATA, and EXT4_FEATURE_INCOMPAT_LARGEDIR.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4: make local symbol ext4_initxattrs static

The ext4_initxattrs symbol is used only in this file, so it should be
declared static.

Signed-off-by: Djalal Harouni <tixxdz@opendz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>