Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

To facilitate additional options to get_user_pages_fast() change the
singular write parameter to be gup_flags.

This patch does not change any functionality.  New functionality will
follow in subsequent patches.

Some of the get_user_pages_fast() call sites were unchanged because they
already passed FOLL_WRITE or 0 for the write parameter.

NOTE: It was suggested to change the ordering of the get_user_pages_fast()
arguments to ensure that callers were converted.  This breaks the current
GUP call site convention of having the returned pages be the final
parameter.  So the suggestion was rejected.

Link: http://lkml.kernel.org/r/20190328084422.29911-4-ira.weiny@intel.com
Link: http://lkml.kernel.org/r/20190317183438.2057-4-ira.weiny@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Mike Marshall <hubcap@omnibond.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull orangefs updates from Mike Marshall:
 "This includes one fix and our "Orangefs through the pagecache" patch
  series which greatly improves our small IO performance and helps us
  pass more xfstests than before.

  Fix:
   - orangefs: truncate before updating size

  Pagecache series:
   - all the rest"

* tag 'for-linus-5.2-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux: (23 commits)
  orangefs: truncate before updating size
  orangefs: copy Orangefs-sized blocks into the pagecache if possible.
  orangefs: pass slot index back to readpage.
  orangefs: remember count when reading.
  orangefs: add orangefs_revalidate_mapping
  orangefs: implement writepages
  orangefs: write range tracking
  orangefs: avoid fsync service operation on flush
  orangefs: skip inode writeout if nothing to write
  orangefs: move do_readv_writev to direct_IO
  orangefs: do not return successful read when the client-core disappeared
  orangefs: implement writepage
  orangefs: migrate to generic_file_read_iter
  orangefs: service ops done for writeback are not killable
  orangefs: remove orangefs_readpages
  orangefs: reorganize setattr functions to track attribute changes
  orangefs: let setattr write to cached inode
  orangefs: set up and use backing_dev_info
  orangefs: hold i_lock during inode_getattr
  orangefs: update attributes rather than relying on server
  ...

Otherwise we race with orangefs_writepage/orangefs_writepages
which and does not expect i_size < page_offset.

Fixes xfstests generic/129.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

->readpage looks in file->private_data to try and find out how the
userspace program set "count" in read(2) or with "dd bs=" or whatever.

->readpage uses "count" and inode->i_size to calculate how much
data Orangefs should deposit in the Orangefs shared buffer, and
remembers which slot the data is in.

After copying data from the Orangefs shared buffer slot into
"the page", readpage tries to increment through the pagecache index
and fill as many pages as it can from the extra data in the shared
buffer. Hopefully these extra pages will soon be needed by the vfs,
and they'll be in the pagecache already.

Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Martin Brandenburg <martin@omnibond.com>

When userspace deposits more than a page of data into the shared buffer,
we'll need to know which slot it is in when we get back to readpage
so that we can try to use the extra data to fill some extra pages.

Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Martin Brandenburg <martin@omnibond.com>

Orangefs wins when it can do IO on large (up to four meg) blocks at a time,
and looses when it has to do tiny "small io" reads and writes. Accessing
Orangefs through the pagecache with the kernel module helps with small io,
both reading and writing, a great deal. Readpage generally tries to fetch a
page (four k) at a time. We'll let users use "count" (as in read(2) or
pread(2) for example) as a knob to control how much data they get from
Orangefs at a time and we'll try to use the data to fill extra
pagecache pages when we get to ->readpage, hopefully resulting in
fewer calls to readpage and Orangefs userspace.

We need a way to remember how they set count so that we can still have
it available when we get to ->readpage.

 - We'll use file->private_data to keep track of "count".
   We'll wrap generic_file_open with orangefs_file_open and
   initialize private_data to NULL there.

 - In ->read_iter we have access to both "count" and file, so
   we'll kmalloc some space onto file->private_data and store
   "count" there.

 - We'll kfree file->private_data each time we visit ->flush and
   reinitialize it to NULL.

Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Martin Brandenburg <martin@omnibond.com>

This is modeled after NFS, except our method is different.  We use a
simple timer to determine whether to invalidate the page cache.  This
is bound to perform.

This addes a sysfs parameter cache_timeout_msecs which controls the time
between page cache invalidations.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

Go through pages and look for a consecutive writable region.  After
finding a number of consecutive writable pages or when finding that
the next page's dirty range is not contiguous and cannot be written
as one request, send the write to the server.

The number of pages is determined by the client-core's buffer size.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>