kleikamp/linux-shaggy forked from torvalds/linux

Convert tmpfs do_shmem_file_read() to shmem_file_read_iter().
Make file_read_iter_actor() global so tmpfs can use it too: delete
file_read_actor(), which was made global in 2.4.4 for use by tmpfs.
Replace tmpfs generic_file_aio_write() by generic_file_write_iter().

Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: linux-mtd@lists.infradead.org

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Dustin Kirkland <dustin.kirkland@gazzang.com>
Cc: ecryptfs@vger.kernel.org

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: Jan Kara <jack@suse.cz>

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: cluster-devel@redhat.com

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Ben Myers <bpm@sgi.com>
Cc: Alex Elder <elder@kernel.org>
Cc: xfs@oss.sgi.com

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>

btrfs can use generic_file_read_iter(). Base btrfs_file_write_iter()
on btrfs_file_aio_write(), then have the latter call the former.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: Zach Brown <zab@zabbo.net>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: linux-btrfs@vger.kernel.org

swap_writepage can now call nfs's write_iter f_op, eliminating the need to
implement for the special-case direct_IO a_op. There is no longer a need to
pass the uio flag through the direct write path.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: linux-nfs@vger.kernel.org

This patch implements the read_iter and write_iter file operations which
allow kernel code to initiate directIO. This allows the loop device to
read and write directly to the server, bypassing the page cache.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: Zach Brown <zab@zabbo.net>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: linux-nfs@vger.kernel.org

use the generic_file_read_iter(), create ext4_file_write_iter() based on
ext4_file_write(), and make ext4_file_write() a wrapper around
ext4_file_write_iter().

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Zach Brown <zab@zabbo.net>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: linux-ext4@vger.kernel.org

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: Joel Becker <jlbec@evilplan.org>
Cc: Zach Brown <zab@zabbo.net>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: ocfs2-devel@oss.oracle.com

These are the simple ones.

File systems that use generic_file_aio_read() and generic_file_aio_write()
can trivially support generic_file_read_iter() and generic_file_write_iter().

This patch adds those file_operations for 9p, adfs, affs, bfs, exofs, ext2,
ext3, fat, f2fs, hfs, hfsplus, hostfs, hpfs, jfs, jffs2, logfs, minix, nilfs2,
omfs, ramfs, reiserfs, romfs, sysv, and ufs.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: Boaz Harrosh <bharrosh@panasas.com>
Cc: Zach Brown <zab@zabbo.net>

File systems implementing read_iter & write_iter should not be required
to keep aio_read and aio_write as well. The vfs should always call
read/write_iter if they exist. This will make it easier to remove the
aio_read/write operation in the future.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Zach Brown <zab@zabbo.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: linux-aio@kvack.org

Create functions to simplify if file_ops contain either a read
or aio_read op, or likewise write or aio_write. We will be adding
read_iter and write_iter and don't need to be complicating the code
in multiple places.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

This uses the new kernel aio interface to process loopback IO by
submitting concurrent direct aio.  Previously loop's IO was serialized
by synchronous processing in a thread.

The aio operations specify the memory for the IO with the bio_vec arrays
directly instead of mappings of the pages.

The use of aio operations is enabled when the backing file supports the
read_iter, write_iter and direct_IO methods.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

This adds iocb cmds which specify that memory is held in iov_iter
structures.  This lets kernel callers specify memory that can be
expressed in an iov_iter, which includes pages in bio_vec arrays.

Only kernel callers can provide an iov_iter so it doesn't make a lot of
sense to expose the IOCB_CMD values for this as part of the user space
ABI.

But kernel callers should also be able to perform the usual aio
operations which suggests using the the existing operation namespace and
support code.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Zach Brown <zab@zabbo.net>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: linux-aio@kvack.org

This adds an interface that lets kernel callers submit aio iocbs without
going through the user space syscalls.  This lets kernel callers avoid
the management limits and overhead of the context.  It will also let us
integrate aio operations with other kernel apis that the user space
interface doesn't have access to.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Zach Brown <zab@zabbo.net>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: linux-aio@kvack.org

Right now only callers of generic_perform_write() pack their iovec
arguments into an iov_iter structure.  All the callers higher up in the
stack work on raw iovec arguments.

This patch introduces the use of the iov_iter abstraction higher up the
stack.  Private generic path functions are changed to operation on
iov_iter instead of on raw iovecs.  Exported interfaces that take iovecs
immediately pack their arguments into an iov_iter and call into the
shared functions.

File operation struct functions are added with iov_iter as an argument
so that callers to the generic file system functions can specify
abstract memory rather than iovec arrays only.

Almost all of this patch only transforms arguments and shouldn't change
functionality.  The buffered read path is the exception.  We add a
read_actor function which uses the iov_iter helper functions instead of
operating on each individual iovec element.  This may improve
performance as the iov_iter helper can copy multiple iovec elements from
one mapped page cache page.

As always, the direct IO path is special.  Sadly, it may still be
cleanest to have it work on the underlying memory structures directly
instead of working through the iov_iter abstraction.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

The trick here is to initialize the dio state so that do_direct_IO()
consumes the pages we provide and never tries to map user pages.  This
is done by making sure that final_block_in_request covers the page that
we set in the dio.  do_direct_IO() will return before running out of
pages.

The caller is responsible for dirtying these pages, if needed.  We add
an option to the dio struct that makes sure we only dirty pages when
we're operating on iovecs of user addresses.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Zach Brown <zab@zabbo.net>

Change the direct_IO aop to take an iov_iter argument rather than an iovec.
This will get passed down through most filesystems so that only the
__blockdev_direct_IO helper need be aware of whether user or kernel memory
is being passed to the function.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

direct IO treats memory from user iovecs and memory from arrays of
kernel pages very differently.  User memory is pinned and worked with in
batches while kernel pages are always pinned and don't require
additional processing.

Rather than try and provide an abstraction that includes these
different behaviours we let direct IO extract the memory structs and
hand them to the existing code.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

The generic direct write path wants to shorten its memory vector.  It
does this when it finds that it has to perform a partial write due to
LIMIT_FSIZE.  .direct_IO() always performs IO on all of the referenced
memory because it doesn't have an argument to specify the length of the
IO.

We add an iov_iter operation for this so that the generic path can ask
to shorten the memory vector without having to know what kind it is.
We're happy to shorten the kernel copy of the iovec array, but we refuse
to shorten the bio_vec array and return an error in this case.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

This adds a set of iov_iter_ops calls which work with memory which is
specified by an array of bio_vec structs instead of an array of iovec
structs.

The big difference is that the pages referenced by the bio_vec elements
are pinned.  They don't need to be faulted in and we can always use
kmap_atomic() to map them one at a time.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

This duplicates the optimization in file_read_actor as a later patch
will replace it with a call to __iov_iter_copy_to_user().

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

This moves the current iov_iter functions behind an ops struct of
function pointers.  The current iov_iter functions all work with memory
which is specified by iovec arrays of user space pointers.

This patch is part of a series that lets us specify memory with bio_vec
arrays of page pointers.  By moving to an iov_iter operation struct we
can add that support in later patches in this series by adding another
set of function pointers.

I only came to this after having initialy tried to teach the current
iov_iter functions about bio_vecs by introducing conditional branches
that dealt with bio_vecs in all the functions.  It wasn't pretty.  This
approach seems to be the lesser evil.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

A future patch hides the internals of struct iov_iter, so fuse should
be using the supported interface.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: fuse-devel@lists.sourceforge.net

This patch adds __iovec_copy_to_user() which doesn't verify write access
to the user memory to be called from code where that verification has
already been done.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

This adds iov_iter wrappers around copy_to_user() to match the existing
wrappers around copy_from_user().

This will be used by the generic file system buffered read path.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

This moves the iov_iter functions in to their own file.  We're going to
be working on them in upcoming patches.  They become sufficiently large,
and remain self-contained, to justify seperating them from the rest of
the huge mm/filemap.c.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>

Pull vfio fix from Alex Williamson:
 "Fix an incorrect break out of nested loop in iommu mapping code"

* tag 'vfio-v3.12-rc5' of git://github.com/awilliam/linux-vfio:
  VFIO: vfio_iommu_type1: fix bug caused by break in nested loop

…el/git/roland/infiniband

Pull infiniband updates from Roland Dreier:
 "Last batch of IB changes for 3.12: many mlx5 hardware driver fixes
  plus one trivial semicolon cleanup"

* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  IB: Remove unnecessary semicolons
  IB/mlx5: Ensure proper synchronization accessing memory
  IB/mlx5: Fix alignment of reg umr gather buffers
  IB/mlx5: Fix eq names to display nicely in /proc/interrupts
  mlx5: Fix error code translation from firmware to driver
  IB/mlx5: Fix opt param mask according to firmware spec
  mlx5: Fix opt param mask for sq err to rts transition
  IB/mlx5: Disable atomic operations
  mlx5: Fix layout of struct mlx5_init_seg
  mlx5: Keep polling to reclaim pages while any returned
  IB/mlx5: Avoid async events on invalid port number
  IB/mlx5: Decrease memory consumption of mr caches
  mlx5: Remove checksum on command interface commands
  IB/mlx5: Fix memory leak in mlx5_ib_create_srq
  IB/mlx5: Flush cache workqueue before destroying it
  IB/mlx5: Fix send work queue size calculation