The write path code intends to bug if a math error (or unhandled case)
results in a write outside of the current cluster boundaries. The actual
BUG_ON() statements however are incorrect, leading to a crash on kernels
with 64k page size. Fix those by checking against the right variables.

Also, move the assertions higher up within the functions so that they trip
*before* the code starts to mark buffers.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Use zero_user_page() instead of open-coding it.
Signed-off-by: NNate Diller <nate.diller@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Similarly to the page lock / cluster lock inversion in ocfs2_readpage, we
can deadlock on ip_alloc_sem. We can down_read_trylock() instead and just
return AOP_TRUNCATED_PAGE if the operation fails.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

We can otherwise recurse into the file system.
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>

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>

Initially, we had wired things to return a size '1' of holes. Cook up a
small amount of code to find the next extent and calculate the number of
clusters between the virtual offset and the next allocated extent.
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>

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>

ocfs2_get_block() didn't understand sparse files, fix that. Also remove some
code that isn't really useful anymore. We can fix up
ocfs2_direct_IO_get_blocks() at the same time.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

These are no longer used, and can't handle file systems with sparse file
allocation.
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>

The code in extent_map.c is not prepared to deal with a subtree being
rotated between lookups. This can happen when filling holes in sparse files.
Instead of a lengthy patch to update the code (which would likely lose the
benefit of caching subtree roots), we remove most of the algorithms and
implement a simple path based lookup. A less ambitious extent caching scheme
will be added in a later patch.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Under load, OCFS2 would crash in invalidate_inode_pages2_range() because
invalidate_complete_page2() was unable to invalidate a page.  It would
appear that JBD is holding on to the page.  ext3 has a specific
->releasepage() handler to cover this case.

Steal ext3's ->releasepage(), ->invalidatepage(), and ->migratepage(), as
they appear completely appropriate for OCFS2.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

ocfs2_direct_IO_get_blocks() was incorrectly returning -EIO for a direct I/O
read whose start block was past the end of the file allocation tree. Fix
things so that we return a hole instead. do_direct_IO() will then notice
that the range start is past eof and return a short read.

While there, remove the unused vbo_max variable.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

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>

This is mostly a search and replace as ocfs2_journal_handle is now no more
than a container for a handle_t pointer.

ocfs2_commit_trans() becomes very straight forward, and we remove some out
of date comments / code.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

All callers either pass in NULL directly, or a local variable that is
already set to NULL.

The internals of ocfs2_start_trans() get a nice cleanup as a result.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

This sets us up to remove handle->journal.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Now that this is unused and all callers pass NULL, we can safely remove it.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

We weren't always updating i_mtime on writes, so fix ocfs2_commit_write() to
handle this.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>
Acked-by: NZach Brown <zach.brown@oracle.com>

Signed-off-by: NFlorin Malita <fmalita@gmail.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Same as with already do with the file operations: keep them in .rodata and
prevents people from doing runtime patching.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We need to take a data lock around extends to protect the pages that
ocfs2_zero_extend is going to be pulling into the page cache. Otherwise an
extend on one node might populate the page cache with data pages that have
no lock coverage.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Now that get_block() can handle mapping multiple disk blocks, no need to have
->get_blocks().  This patch removes fs specific ->get_blocks() added for DIO
and makes it users use get_block() instead.
Signed-off-by: NBadari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

The OCFS2 file system module.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: NKurt Hackel <kurt.hackel@oracle.com>