linux-toradex.git/fs/ext4/ext4_jbd2.h, branch v2.6.32.52

ext4: Use bitops to read/modify i_flags in struct ext4_inode_info

2010-08-02T17:21:22+00:00

commit 12e9b892002d9af057655d35b44db8ee9243b0dc upstream (as of v2.6.34-git13)

At several places we modify EXT4_I(inode)->i_flags without holding
i_mutex (ext4_do_update_inode, ...). These modifications are racy and
we can lose updates to i_flags. So convert handling of i_flags to use
bitops which are atomic.

https://bugzilla.kernel.org/show_bug.cgi?id=15792

Signed-off-by: Dmitry Monakhov 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: Wait for proper transaction commit on fsync

2009-12-14T17:45:25+00:00

(cherry picked from commit b436b9bef84de6893e86346d8fbf7104bc520645)

We cannot rely on buffer dirty bits during fsync because pdflush can come
before fsync is called and clear dirty bits without forcing a transaction
commit. What we do is that we track which transaction has last changed
the inode and which transaction last changed allocation and force it to
disk on fsync.

Signed-off-by: Jan Kara 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: quota macros cleanup

2009-12-14T17:45:22+00:00

(cherry picked from commit 5aca07eb7d8f14d90c740834d15ca15277f4820c)

Currently all quota block reservation macros contains hard-coded "2"
aka MAXQUOTAS value. This is no good because in some places it is not
obvious to understand what does this digit represent. Let's introduce
new macro with self descriptive name.

Signed-off-by: Dmitry Monakhov 
Acked-by: Mingming Cao 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: Handle nested ext4_journal_start/stop calls without a journal

2009-09-29T15:01:03+00:00

This patch fixes a problem with handling nested calls to
ext4_journal_start/ext4_journal_stop, when there is no journal present.

Signed-off-by: Curt Wohlgemuth 
Signed-off-by: "Theodore Ts'o"

ext4: Fix buffer head reference leak in no-journal mode

2009-07-13T13:07:20+00:00

We found a problem with buffer head reference leaks when using an ext4
partition without a journal.  In particular, calls to ext4_forget() would
not to a brelse() on the input buffer head, which will cause pages they
belong to to not be reclaimable.

Further investigation showed that all places where ext4_journal_forget() and
ext4_journal_revoke() are called are subject to the same problem.  The patch
below changes __ext4_journal_forget/__ext4_journal_revoke to do an explicit
release of the buffer head when the journal handle isn't valid.

Signed-off-by: Curt Wohlgemuth 
Signed-off-by: "Theodore Ts'o"

ext4: fix no journal corruption with locale-gen

2009-07-08T21:11:24+00:00

If there is no journal, ext4_should_writeback_data() should return
TRUE.  This will fix ext4_set_aops() to set ext4_da_ops in the case of
delayed allocation; otherwise ext4_journaled_aops gets used by
default, which doesn't handle delayed allocation properly.

The advantage of using ext4_should_writeback_data() approach is that
it should handle nobh better as well.

Thanks to Curt Wohlgemuth for investigating this problem, and Aneesh
Kumar for suggesting this approach.

Signed-off-by: "Theodore Ts'o"

ext4: Remove "extents" mount option

2009-01-06T19:53:16+00:00

This mount option is largely superfluous, and in fact the way it was
implemented was buggy; if a filesystem which did not have the extents
feature flag was mounted -o extents, the filesystem would attempt to
create and use extents-based file even though the extents feature flag
was not eabled.  The simplest thing to do is to nuke the mount option
entirely.  It's not all that useful to force the non-creation of new
extent-based files if the filesystem can support it.

Signed-off-by: "Theodore Ts'o"

ext4: Allow ext4 to run without a journal

2009-01-07T05:06:22+00:00

A few weeks ago I posted a patch for discussion that allowed ext4 to run
without a journal.  Since that time I've integrated the excellent
comments from Andreas and fixed several serious bugs.  We're currently
running with this patch and generating some performance numbers against
both ext2 (with backported reservations code) and ext4 with and without
a journal.  It just so happens that running without a journal is
slightly faster for most everything.

We did
	iozone -T -t 4 s 2g -r 256k -T -I -i0 -i1 -i2

which creates 4 threads, each of which create and do reads and writes on
a 2G file, with a buffer size of 256K, using O_DIRECT for all file opens
to bypass the page cache.  Results:

                     ext2        ext4, default   ext4, no journal
  initial writes   13.0 MB/s        15.4 MB/s          15.7 MB/s
  rewrites         13.1 MB/s        15.6 MB/s          15.9 MB/s
  reads            15.2 MB/s        16.9 MB/s          17.2 MB/s
  re-reads         15.3 MB/s        16.9 MB/s          17.2 MB/s
  random readers    5.6 MB/s         5.6 MB/s           5.7 MB/s
  random writers    5.1 MB/s         5.3 MB/s           5.4 MB/s 

So it seems that, so far, this was a useful exercise.

Signed-off-by: Frank Mayhar 
Signed-off-by: "Theodore Ts'o"

ext4: journal credits calulation cleanup and fix for non-extent writepage

2008-08-20T02:16:07+00:00

When considering how many journal credits are needed for modifying a
chunk of data, we need to account for the super block, inode block,
quota blocks and xattr block, indirect/index blocks, also, group bitmap
and group descriptor blocks for new allocation (including data and
indirect/index blocks). There are many places in ext4 do the calculation
on their own and often missed one or two meta blocks, and often they
assume single block allocation, and did not considering the multile
chunk of allocation case.

This patch is trying to cleanup current journal credit code, provides
some common helper funtion to calculate the journal credits, to be used
for writepage, writepages, DIO, fallocate, migration, defrag, and for
both nonextent and extent files.

This patch modified the writepage/write_begin credit caculation for
nonextent files, to use the new helper function. It also fixed the
problem that writepage on nonextent files did not consider the case
blocksize 
Reviewed-by: Aneesh Kumar K.V 
Signed-off-by: "Theodore Ts'o"

ext4: Use new framework for data=ordered mode in JBD2

2008-07-11T23:27:31+00:00

This patch makes ext4 use inode-based implementation of data=ordered mode
in JBD2. It allows us to unify some data=ordered and data=writeback paths
(especially writepage since we don't have to start a transaction anymore)
and remove some buffer walking.

Updated fix from Aneesh Kumar K.V 
to fix file system hang due to corrupt jinode values.

Signed-off-by: Jan Kara 
Signed-off-by: Aneesh Kumar K.V 
Signed-off-by: Mingming Cao 
Signed-off-by: "Theodore Ts'o"