ocfs2_align_clusters_to_page_index() needs to cast the clusters shift to
pgoff_t and ocfs2_file_buffered_write() needs loff_t when calculating
destination start for memcpy.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

There's no need to recalculate things via ocfs2_max_file_offset() as we've
already done that to fill s_maxbytes, so use that instead. We can also
un-export ocfs2_max_file_offset() then.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

ocfs2_update_inode_atime() calls ocfs2_mark_inode_dirty() to push changes
from the struct inode into the ocfs2 disk inode. The problem is,
ocfs2_mark_inode_dirty() might change other fields, depending on what
happened to the struct inode. Since we don't always have locking to
serialize changes to other fields (like i_size, etc), just fix things up to
only touch the atime field.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

kunmap_atomic() takes the virtual address, not the mapped page as
argument.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Plug ocfs2 into the ->fallocate() callback. This just re-uses the existing
preallocation code.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Mark variables with uninitialized_var() if such a warning appears,
and analysis proves that the var is initialized properly on all paths
it is used.
Signed-off-by: NJeff Garzik <jeff@garzik.org>

We re-use the RESVSP/UNRESVSP ioctls from xfs which allow the user to
allocate and deallocate regions to a file without zeroing data or changing
i_size.

Though renamed, the structure passed in from user is identical to struct
xfs_flock64. The three fields that are actually used right now are l_whence,
l_start and l_len.

This should get ocfs2 immediate compatibility with userspace software using
the pre-existing xfs ioctls.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Provide an internal interface for the removal of arbitrary file regions.

ocfs2_remove_inode_range() takes a byte range within a file and will remove
existing extents within that range. Partial clusters will be zeroed so that
any read from within the region will return zeros.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

The partial cluster zeroing code used during truncate usually assumes that
the rightmost byte in the range to be zeroed lies on a cluster boundary.
This makes sense for truncate, but punching holes might require zeroing on
non-aligned rightmost boundaries.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

This can now be trivially supported with re-use of our existing extend code.

ocfs2_allocate_unwritten_extents() takes a start offset and a byte length
and iterates over the inode, adding extents (marked as unwritten) until len
is reached. Existing extents are skipped over.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Update the write code to detect when the user is asking to write to an
unwritten extent. Like writing to a hole, we must zero the region between
the write and the cluster boundaries. Most of the existing cluster zeroing
logic can be re-used with some additional checks for the unwritten flag on
extent records.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Implement cluster consistent shared writeable mappings using the
->page_mkwrite() callback.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Use some ideas from the new-aops patch series and turn
ocfs2_buffered_write_cluster() into a 2 stage operation with the caller
copying data in between. The code now understands multiple cluster writes as
a result of having to deal with a full page write for greater than 4k pages.

This sets us up to easily call into the write path during ->page_mkwrite().
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Use of the alloc sem during truncate was too narrow - we want to protect
the i_size change and page truncation against mmap now.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

The name 'pin' was badly chosen, it doesn't pin a pipe buffer
in the most commonly used sense in the kernel. So change the
name to 'confirm', after debating this issue with Hugh
Dickins a bit.

A good return from ->confirm() means that the buffer is really
there, and that the contents are good.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

We need to move even more stuff into the header so that folks can use
the splice_to_pipe() implementation instead of open-coding a lot of
pipe knowledge (see relay implementation), so move to our own header
file finally.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

They can use generic_file_splice_read() instead. Since sys_sendfile() now
prefers that, there should be no change in behaviour.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

A bit of a cheat, it actually just copies the data to userspace. But
this makes the interface nice and symmetric and enables people to build
on splice, with room for future improvement in performance.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

For direct splicing (or private splicing), the output may not be a file.
So abstract out the handling into a specified actor function and put
the data in the splice_desc structure earlier, so we can build on top
of that.

This is the first step in better splice handling for drivers, and also
for implementing vmsplice _to_ user memory.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

We weren't calling this before, but since ocfs2 handles the entire truncate
operation, we should.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

None of these are actually harmful, but the noise makes looking for real
problems difficult.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

This patch makes the following needlessly global functions static:
- aops.c: ocfs2_write_data_page()
- dlmglue.c: ocfs2_dump_meta_lvb_info()
- file.c: ocfs2_set_inode_size()
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

We need this to support 32 bit system calls on 64 bit kernels.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Cluster locking might have been redone because a direct write won't
complete, so this needs to be reflected in the iocb.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Older file systems which didn't support holes did a dumb calculation of
i_blocks based on i_size. This is no longer accurate, so fix things up to
take actual allocation into account.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Return an optional extent flags field from our lookup functions and wire up
callers to treat unwritten regions as holes for the purpose of returning
zeros to the user.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Due to the size of our group bitmaps, we'll never have a leaf node extent
record with more than 16 bits worth of clusters. Split e_clusters up so that
leaf nodes can get a flags field where we can mark unwritten extents.
Interior nodes whose length references all the child nodes beneath it can't
split their e_clusters field, so we use a union to preserve sizing there.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

We need to fill holes during a splice write. Provide our own splice write
actor which can call ocfs2_file_buffered_write() with a splice-specific
callback.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Since we don't zero on extend anymore, truncate needs to be fixed up to zero
the part of a file between i_size and and end of it's cluster. Otherwise a
subsequent extend could expose bad data.

This introduced a new helper, which can be used in ocfs2_write().
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Unfortunately, ocfs2 can no longer make use of generic_file_aio_write_nlock()
because allocating writes will require zeroing of pages adjacent to the I/O
for cluster sizes greater than page size.

Implement a custom file write here, which can order page locks for zeroing.
This also has the advantage that cluster locks can easily be ordered outside
of the page locks.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Right now, file allocation for ocfs2 is done within ocfs2_extend_file(),
which is either called from ->setattr() (for an i_size change), or at the
top of ocfs2_file_aio_write().

Inodes on file systems with sparse file support will want to do their
allocation during the actual write call.

In either case the cluster locking decisions are the same. We abstract out
that code into a new function, ocfs2_lock_allocators() which will be used by
a later patch to enable writing to sparse files.

This also provides a nice cleanup of ocfs2_extend_allocation().
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

For ocfs2_truncate_file(), we eliminate the "simple" truncate case which no
longer exists since i_size is not tied to i_clusters. In
ocfs2_extend_file(), we skip the allocation / page zeroing code for file
systems which understand sparse files.

The core truncate code is changed to do a bottom up tree traversal. This
gets abstracted out into it's own function. To make things more readable,
most of the special case handling for in-inode extents from
ocfs2_do_truncate() is also removed.

Though write support for sparse files comes in a later patch, we at least
update ocfs2_prepare_inode_for_write() to skip allocation for sparse files.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Introduce tree rotations into the b-tree code. This will allow ocfs2 to
support sparse files. Much of the added code is designed to be generic (in
the ocfs2 sense) so that it can later be re-used to implement large
extended attributes.

This patch only adds the rotation code and does minimal updates to callers
of the extent api.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

We don't want to print anything at all in ocfs2_lookup() when getting an
error from ocfs2_iget() - it could be something as innocuous as a signal
being detected in the dlm.

ocfs2_permission() should filter on -ENOENT which ocfs2_meta_lock() can
return if the inode was deleted on another node.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Many struct inode_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This can come from NFSD.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Errors from generic_permission() can happen in valid cases and shouldn't be
reported.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Update ocfs2_should_update_atime() to understand the MNT_RELATIME flag and
to test against mtime / ctime accordingly.

[akpm@osdl.org: cleanups]
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>
Cc: Valerie Henson <val_henson@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NJosef Sipek <jsipek@fsl.cs.sunysb.edu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>