Essentially, the minimal variant of ->evict_inode().  It's
a trimmed-down clear_inode(), sans any fs callbacks.  Once
it returns we know that no async writeback will be happening;
every ->evict_inode() instance should do that once and do that
before doing anything ->write_inode() could interfere with
(e.g. freeing the on-disk inode).
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

All call chains to clear_inode() pass through evict_inode() and
clear_inode() should be called by evict_inode() exactly once.
So we can pull i_bdev/i_cdev detaching up to evict_inode() itself.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

The first spoils - hugetlb can use default ->drop_inode() now.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Hybrid of ->clear_inode() and ->delete_inode(); if present, does
all fs work to be done when in-core inode is about to be gone,
for whatever reason.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

For now, just a straightforward merge
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

add I_CLEAR instead of replacing I_FREEING with it.  I_CLEAR is
equivalent to I_FREEING for almost all code looking at either;
it's there to keep track of having called clear_inode() exactly
once per inode lifetime, at some point after having set I_FREEING.
I_CLEAR and I_FREEING never get set at the same time with the
current code, so we can switch to setting i_flags to I_FREEING | I_CLEAR
instead of I_CLEAR without loss of information.  As the result of
such change, checks become simpler and the amount of code that needs
to know about I_CLEAR shrinks a lot.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Copy and simplify in the only two users remaining.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Convert XFS to the new truncate sequence.  We still can have errors after
updating the file size in xfs_setattr, but these are real I/O errors and lead
to a transaction abort and filesystem shutdown, so they are not an issue.

Errors from ->write_begin and write_end can now be handled correctly because
we can actually get rid of the delalloc extents while previous the buffer
state was stipped in block_invalidatepage.

There is still no error handling for ->direct_IO, because doing so will need
some major restructuring given that we only have the iolock shared and do not
hold i_mutex at all.  Fortunately leaving the normally allocated blocks behind
there is not a major issue and this will get cleaned up by xfs_free_eofblock
later.

Note: the patch is against Al's vfs.git tree as that contains the nessecary
preparations.  I'd prefer to get it applied there so that we can get some
testing in linux-next.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

These changes are crafted based on the similar
conversion done to ext2 by Nick Piggin.

* Remove the deprecated ->truncate vector. Let exofs_setattr
  take care of on-disk size updates.
* Call truncate_pagecache on the unused pages if
  write_begin/end fails.
* Cleanup exofs_delete_inode that did stupid inode
  writes and updates on an inode that will be
  removed.
* And finally get rid of exofs_get_block. We never
  had any blocks it was all for calling nobh_truncate_page.
  nobh_truncate_page is not actually needed in exofs since
  the last page is complete and gone, just like all the other
  pages. There is no partial blocks in exofs.

I've tested with this patch, and there are no apparent
failures, so far.

CC: Nick Piggin <npiggin@suse.de>
CC: Christoph Hellwig <hch@lst.de>
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Make sure we check the truncate constraints early on in ->setattr by adding
those checks to inode_change_ok.  Also clean up and document inode_change_ok
to make this obvious.

As a fallout we don't have to call inode_newsize_ok from simple_setsize and
simplify it down to a truncate_setsize which doesn't return an error.  This
simplifies a lot of setattr implementations and means we use truncate_setsize
almost everywhere.  Get rid of fat_setsize now that it's trivial and mark
ext2_setsize static to make the calling convention obvious.

Keep the inode_newsize_ok in vmtruncate for now as all callers need an
audit for its removal anyway.

Note: setattr code in ecryptfs doesn't call inode_change_ok at all and
needs a deeper audit, but that is left for later.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Make sure we call inode_change_ok before doing any changes in ->setattr,
and make sure to call it even if our fs wants to ignore normal UNIX
permissions, but use the ATTR_FORCE to skip those.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Replace inode_setattr with opencoded variants of it in all callers.  This
moves the remaining call to vmtruncate into the filesystem methods where it
can be replaced with the proper truncate sequence.

In a few cases it was obvious that we would never end up calling vmtruncate
so it was left out in the opencoded variant:

 spufs: explicitly checks for ATTR_SIZE earlier
 btrfs,hugetlbfs,logfs,dlmfs: explicitly clears ATTR_SIZE earlier
 ufs: contains an opencoded simple_seattr + truncate that sets the filesize just above

In addition to that ncpfs called inode_setattr with handcrafted iattrs,
which allowed to trim down the opencoded variant.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

With the new truncate sequence every filesystem that wants to support file
size changes on disk needs to implement its own ->setattr.  So instead
of calling inode_setattr which supports size changes call into a simple
method that doesn't support this.  simple_setattr is almost what we
want except that it does not mark the inode dirty after changes.  Given
that marking the inode dirty is a no-op for the simple in-memory filesystems
that use simple_setattr currently just add the mark_inode_dirty call.

Also add a WARN_ON for the presence of a truncate method to simple_setattr
to catch new instances of it during the transition period.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Despite its name it's now a generic implementation of ->setattr, but
rather a helper to copy attributes from a struct iattr to the inode.
Rename it to setattr_copy to reflect this fact.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

For the new truncate sequence every filesystem that wants to truncate on-disk
state needs a seattr method.  Convert the remaining filesystems that implement
the truncate inode operation to have its own setattr method.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Move the call to vmtruncate to get rid of accessive blocks to the callers
in preparation of the new truncate sequence and rename the non-truncating
version to block_write_begin.

While we're at it also remove several unused arguments to block_write_begin.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Split up the block_write_begin implementation - __block_write_begin is a new
trivial wrapper for block_prepare_write that always takes an already
allocated page and can be either called from block_write_begin or filesystem
code that already has a page allocated.  Remove the handling of already
allocated pages from block_write_begin after switching all callers that
do it to __block_write_begin.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

For filesystem that implement directories in pagecache we call
block_write_begin with an already allocated page for this code, while the
normal regular file write path uses the default block_write_begin behaviour.

Get rid of the __foofs_write_begin helper and opencode the normal write_begin
call in foofs_write_begin, while adding a new foofs_prepare_chunk helper for
the directory code.  The added benefit is that foofs_prepare_chunk has
a much saner calling convention.

Note that the interruptible flag passed into block_write_begin is always
ignored if we already pass in a page (see next patch for details), and
we never were doing truncations of exessive blocks for this case either so we
can switch directly to block_write_begin_newtrunc.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Move the call to vmtruncate to get rid of accessive blocks to the callers
in preparation of the new truncate sequence and rename the non-truncating
version to cont_write_begin.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Move the call to vmtruncate to get rid of accessive blocks to the only
remaining caller and rename the non-truncating version to nobh_write_begin.

Get rid of the superflous file argument to it while we're at it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Move the call to vmtruncate to get rid of accessive blocks to the callers
in prepearation of the new truncate calling sequence.  This was only done
for DIO_LOCKING filesystems, so the __blockdev_direct_IO_newtrunc variant
was not needed anyway.  Get rid of blockdev_direct_IO_no_locking and
its _newtrunc variant while at it as just opencoding the two additional
paramters is shorted than the name suffix.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

if kmalloc fails, we still need to drop the inode, as we do
on other failure exits.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

a) count file openers correctly; i_count use was completely wrong
b) use new mutex for exclusion between final close/open/truncate,
to protect tailpacking logics.  i_mutex use was wrong and resulted
in deadlocks.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

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

* 'for-linus' of git://oss.sgi.com/xfs/xfs: (49 commits)
  xfs simplify and speed up direct I/O completions
  xfs: move aio completion after unwritten extent conversion
  direct-io: move aio_complete into ->end_io
  xfs: fix big endian build
  xfs: clean up xfs_bmap_get_bp
  xfs: simplify xfs_truncate_file
  xfs: kill the b_strat callback in xfs_buf
  xfs: remove obsolete osyncisosync mount option
  xfs: clean up filestreams helpers
  xfs: fix gcc 4.6 set but not read and unused statement warnings
  xfs: Fix build when CONFIG_XFS_POSIX_ACL=n
  xfs: fix unsigned underflow in xfs_free_eofblocks
  xfs: use GFP_NOFS for page cache allocation
  xfs: fix memory reclaim recursion deadlock on locked inode buffer
  xfs: fix xfs_trans_add_item() lockdep warnings
  xfs: simplify and remove xfs_ireclaim
  xfs: don't block on buffer read errors
  xfs: move inode shrinker unregister even earlier
  xfs: remove a dmapi leftover
  xfs: writepage always has buffers
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: (29 commits)
  cifs: fsc should not default to "on"
  [CIFS] remove redundant path walking in dfs_do_refmount
  cifs: ignore the "mand", "nomand" and "_netdev" mount options
  cifs: map NT_STATUS_ERROR_WRITE_PROTECTED to -EROFS
  cifs: don't allow cifs_iget to match inodes of the wrong type
  [CIFS] relinquish fscache cookie before freeing CIFSTconInfo
  cifs: add separate cred_uid field to sesInfo
  fs: cifs: check kmalloc() result
  [CIFS] Missing ifdef
  [CIFS] Missing line from previous commit
  [CIFS] Fix build break when CONFIG_CIFS_FSCACHE disabled
  cifs: add mount option to enable local caching
  cifs: read pages from FS-Cache
  cifs: store pages into local cache
  cifs: FS-Cache page management
  cifs: define inode-level cache object and register them
  cifs: define superblock-level cache index objects and register them
  cifs: remove unused cifsUidInfo struct
  cifs: clean up cifs_find_smb_ses (try #2)
  cifs: match secType when searching for existing tcp session
  ...

* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (291 commits)
  ARM: AMBA: Add pclk support to AMBA bus infrastructure
  ARM: 6278/2: fix regression in RealView after the introduction of pclk
  ARM: 6277/1: mach-shmobile: Allow users to select HZ, default to 128
  ARM: 6276/1: mach-shmobile: remove duplicate NR_IRQS_LEGACY
  ARM: 6246/1: mmci: support larger MMCIDATALENGTH register
  ARM: 6245/1: mmci: enable hardware flow control on Ux500 variants
  ARM: 6244/1: mmci: add variant data and default MCICLOCK support
  ARM: 6243/1: mmci: pass power_mode to the translate_vdd callback
  ARM: 6274/1: add global control registers definition header file for nuc900
  mx2_camera: fix type of dma buffer virtual address pointer
  mx2_camera: Add soc_camera support for i.MX25/i.MX27
  arm/imx/gpio: add spinlock protection
  ARM: Add support for the LPC32XX arch
  ARM: LPC32XX: Arch config menu supoport and makefiles
  ARM: LPC32XX: Phytec 3250 platform support
  ARM: LPC32XX: Misc support functions
  ARM: LPC32XX: Serial support code
  ARM: LPC32XX: System suspend support
  ARM: LPC32XX: GPIO, timer, and IRQ drivers
  ARM: LPC32XX: Clock driver
  ...

avoid potential stack overflow by correctly checking count parameter
Reported-by: NIlja <ilja@netric.org>
Signed-off-by: NHelge Deller <deller@gmx.de>
Acked-by: NKyle McMartin <kyle@mcmartin.ca>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I'm not sure why this was merged with this flag hardcoded on, but it
seems quite dangerous. Turn it off.

Also, mount.cifs hands unrecognized options off to the kernel so there
should be no need for changes there in order to support this.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Reviewed-by: NDave Howells <dhowells@redhat.com>
Signed-off-by: NIgor Mammedov <niallain@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

These are all handled by the userspace mount programs, but older versions
of mount.cifs also handed them off to the kernel. Ignore them.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Seems like a more sensible mapping than -EIO.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

If the type is different from what we think it should be, then don't
match the existing inode.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Doh, fix a use after free bug.
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Reviewed-and-Tested-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Right now, there's no clear separation between the uid that owns the
credentials used to do the mount and the overriding owner of the files
on that mount.

Add a separate cred_uid field that is set to the real uid
of the mount user. Unlike the linux_uid, the uid= option does not
override this parameter. The parm is sent to cifs.upcall, which can then
preferentially use the creduid= parm instead of the uid= parm for
finding credentials.

This is not the only way to solve this. We could try to do all of this
in kernel instead by having a module parameter that affects what gets
passed in the uid= field of the upcall. That said, we have a lot more
flexibility to change things in userspace so I think it probably makes
sense to do it this way.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>