linux-toradex.git/fs/xfs/xfs_dir2_leaf.c, branch v3.2.37

xfs: introduce xfs_bmapi_read()

2011-10-12T02:15:03+00:00

xfs_bmapi() currently handles both extent map reading and
allocation. As a result, the code is littered with "if (wr)"
branches to conditionally do allocation operations if required.
This makes the code much harder to follow and causes significant
indent issues with the code.

Given that read mapping is much simpler than allocation, we can
split out read mapping from xfs_bmapi() and reuse the logic that
we have already factored out do do all the hard work of handling the
extent map manipulations. The results in a much simpler function for
the common extent read operations, and will allow the allocation
code to be simplified in another commit.

Once xfs_bmapi_read() is implemented, convert all the callers of
xfs_bmapi() that are only reading extents to use the new function.

Signed-off-by: Dave Chinner 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Alex Elder

xfs: factor out xfs_dir2_leaf_find_stale

2011-07-13T11:43:48+00:00

Signed-off-by: Christoph Hellwig 
Reviewed-by: Alex Elder 
Reviewed-by: Dave Chinner

xfs: reshuffle dir2 headers

2011-07-13T11:43:48+00:00

Replace the current mess of dir2 headers with just three that have a clear
purpose:

 - xfs_dir2_format.h for all format definitions, including the inline helpers
   to access our variable size structures
 - xfs_dir2_priv.h for all prototypes that are internal to the dir2 code
   and not needed by anything outside of the directory code.  For this
   purpose xfs_da_btree.c, and phase6.c in xfs_repair are considered part
   of the directory code.
 - xfs_dir2.h for the public interface to the directory code

In addition to the reshuffle I have also update the comments to not only
match the new file structure, but also to describe the directory format
better.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Alex Elder 
Reviewed-by: Dave Chinner

xfs: byteswap constants instead of variables

2011-07-08T12:36:05+00:00

Micro-optimize various comparisms by always byteswapping the constant
instead of the variable, which allows to do the swap at compile instead
of runtime.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Alex Elder 
Reviewed-by: Dave Chinner

xfs: cleanup struct xfs_dir2_leaf

2011-07-08T12:35:53+00:00

Simplify the confusing xfs_dir2_leaf structure.  It is supposed to describe
an XFS dir2 leaf format btree block, but due to the variable sized nature
of almost all elements in it it can't actuall do anything close to that
job.   Remove the members that are after the first variable sized array,
given that they could only be used for sizeof expressions that can as well
just use the underlying types directly, and make the ents array a real
C99 variable sized array.

Also factor out the xfs_dir2_leaf_size, to make the sizing of a leaf
entry which already was convoluted somewhat readable after using the
longer type names in the sizeof expressions.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Alex Elder 
Reviewed-by: Dave Chinner

xfs: kill struct xfs_dir2_data

2011-07-08T12:35:42+00:00

Remove the confusing xfs_dir2_data structure.  It is supposed to describe
an XFS dir2 data btree block, but due to the variable sized nature of
almost all elements in it it can't actuall do anything close to that
job.  In addition to accessing the fixed offset header structure it was
only used to get a pointer to the first dir or unused entry after it,
which can be trivially replaced by pointer arithmetics on the header
pointer.  For most users that is actually more natural anyway, as they
don't use a typed pointer but rather a character pointer for further
arithmetics.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Alex Elder 
Reviewed-by: Dave Chinner

xfs: avoid usage of struct xfs_dir2_data

2011-07-08T12:35:38+00:00

In most places we can simply pass around and use the struct xfs_dir2_data_hdr,
which is the first and most important member of struct xfs_dir2_data instead
of the full structure.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Alex Elder 
Reviewed-by: Dave Chinner

xfs: avoid usage of struct xfs_dir2_block

2011-07-08T12:35:27+00:00

In most places we can simply pass around and use the struct xfs_dir2_data_hdr,
which is the first and most important member of struct xfs_dir2_block instead
of the full structure.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Alex Elder 
Reviewed-by: Dave Chinner

xfs: factor out xfs_dir2_leaf_find_entry

2011-07-08T12:34:59+00:00

Add a new xfs_dir2_leaf_find_entry helper to factor out some duplicate code
from xfs_dir2_leaf_addname xfs_dir2_leafn_add.  Found by Eric Sandeen using
an automated code duplication checker.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Alex Elder 
Reviewed-by: Dave Chinner

xfs: remove xfs_buf wrappers

2010-10-18T20:08:07+00:00

Stop having two different names for many buffer functions and use
the more descriptive xfs_buf_* names directly.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Alex Elder