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  1. 22 1月, 2009 25 次提交
  3. 07 1月, 2009 1 次提交
  5. 06 1月, 2009 4 次提交
  7. 05 1月, 2009 1 次提交
  9. 01 1月, 2009 1 次提交
  11. 30 10月, 2008 1 次提交
    • C
      Btrfs: Add zlib compression support · c8b97818
      由 Chris Mason 提交于 
      This is a large change for adding compression on reading and writing,
both for inline and regular extents.  It does some fairly large
surgery to the writeback paths.

Compression is off by default and enabled by mount -o compress.  Even
when the -o compress mount option is not used, it is possible to read
compressed extents off the disk.

If compression for a given set of pages fails to make them smaller, the
file is flagged to avoid future compression attempts later.

* While finding delalloc extents, the pages are locked before being sent down
to the delalloc handler.  This allows the delalloc handler to do complex things
such as cleaning the pages, marking them writeback and starting IO on their
behalf.

* Inline extents are inserted at delalloc time now.  This allows us to compress
the data before inserting the inline extent, and it allows us to insert
an inline extent that spans multiple pages.

* All of the in-memory extent representations (extent_map.c, ordered-data.c etc)
are changed to record both an in-memory size and an on disk size, as well
as a flag for compression.

From a disk format point of view, the extent pointers in the file are changed
to record the on disk size of a given extent and some encoding flags.
Space in the disk format is allocated for compression encoding, as well
as encryption and a generic 'other' field.  Neither the encryption or the
'other' field are currently used.

In order to limit the amount of data read for a single random read in the
file, the size of a compressed extent is limited to 128k.  This is a
software only limit, the disk format supports u64 sized compressed extents.

In order to limit the ram consumed while processing extents, the uncompressed
size of a compressed extent is limited to 256k.  This is a software only limit
and will be subject to tuning later.

Checksumming is still done on compressed extents, and it is done on the
uncompressed version of the data.  This way additional encodings can be
layered on without having to figure out which encoding to checksum.

Compression happens at delalloc time, which is basically singled threaded because
it is usually done by a single pdflush thread.  This makes it tricky to
spread the compression load across all the cpus on the box.  We'll have to
look at parallel pdflush walks of dirty inodes at a later time.

Decompression is hooked into readpages and it does spread across CPUs nicely.
Signed-off-by: NChris Mason <chris.mason@oracle.com>
      c8b97818
  13. 23 10月, 2008 1 次提交
    • A
      [patch 1/3] FS_MBCACHE: don't needlessly make it built-in · 2c512397
      由 Adrian Bunk 提交于 
      Assume you have:
- one or more of ext2/3/4 statically built into your kernel
- none of these with extended attributes enabled and
- want to add onother one of ext2/3/4 modular and with
  extended attributes enabled

then you currently have to reboot to use it since this results in
CONFIG_FS_MBCACHE=y.

That's not a common issue, but I just ran into it and since there's no
reason to get a built-in mbcache in this case this patch fixes it.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Cc: Andreas Gruenbacher <agruen@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      2c512397
  15. 21 10月, 2008 1 次提交
  17. 20 10月, 2008 1 次提交
  19. 16 10月, 2008 1 次提交
  21. 14 10月, 2008 1 次提交
    • J
      ocfs2: Switch over to JBD2. · 2b4e30fb
      由 Joel Becker 提交于 
      ocfs2 wants JBD2 for many reasons, not the least of which is that JBD is
limiting our maximum filesystem size.

It's a pretty trivial change.  Most functions are just renamed.  The
only functional change is moving to Jan's inode-based ordered data mode.
It's better, too.

Because JBD2 reads and writes JBD journals, this is compatible with any
existing filesystem.  It can even interact with JBD-based ocfs2 as long
as the journal is formated for JBD.

We provide a compatibility option so that paranoid people can still use
JBD for the time being.  This will go away shortly.

[ Moved call of ocfs2_begin_ordered_truncate() from ocfs2_delete_inode() to
  ocfs2_truncate_for_delete(). --Mark ]
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>
      2b4e30fb
  23. 13 10月, 2008 2 次提交