linux.git/fs/ext4/super.c, branch v3.17

jbd2: fix descriptor block size handling errors with journal_csum

2014-08-29T02:22:29+00:00

It turns out that there are some serious problems with the on-disk
format of journal checksum v2.  The foremost is that the function to
calculate descriptor tag size returns sizes that are too big.  This
causes alignment issues on some architectures and is compounded by the
fact that some parts of jbd2 use the structure size (incorrectly) to
determine the presence of a 64bit journal instead of checking the
feature flags.

Therefore, introduce journal checksum v3, which enlarges the
descriptor block tag format to allow for full 32-bit checksums of
journal blocks, fix the journal tag function to return the correct
sizes, and fix the jbd2 recovery code to use feature flags to
determine 64bitness.

Add a few function helpers so we don't have to open-code quite so
many pieces.

Switching to a 16-byte block size was found to increase journal size
overhead by a maximum of 0.1%, to convert a 32-bit journal with no
checksumming to a 32-bit journal with checksum v3 enabled.

Signed-off-by: Darrick J. Wong 
Reported-by: TR Reardon 
Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org

ext4: rearrange initialization to fix EXT4FS_DEBUG

2014-07-15T10:01:38+00:00

The EXT4FS_DEBUG is a *very* developer specific #ifdef designed for
ext4 developers only.  (You have to modify fs/ext4/ext4.h to enable
it.)

Rearrange how we initialize data structures to avoid calling
ext4_count_free_clusters() until the multiblock allocator has been
initialized.

This also allows us to only call ext4_count_free_clusters() once, and
simplifies the code somewhat.

(Thanks to Chen Gang  for pointing out a
!CONFIG_SMP compile breakage in the original patch.)

Signed-off-by: Theodore Ts'o 
Reviewed-by: Lukas Czerner

ext4: revert commit which was causing fs corruption after journal replays

2014-07-11T17:55:40+00:00

Commit 007649375f6af2 ("ext4: initialize multi-block allocator before
checking block descriptors") causes the block group descriptor's count
of the number of free blocks to become inconsistent with the number of
free blocks in the allocation bitmap.  This is a harmless form of fs
corruption, but it causes the kernel to potentially remount the file
system read-only, or to panic, depending on the file systems's error
behavior.

Thanks to Eric Whitney for his tireless work to reproduce and to find
the guilty commit.

Fixes: 007649375f6af2 ("ext4: initialize multi-block allocator before checking block descriptors"

Cc: stable@vger.kernel.org  # 3.15
Reported-by: David Jander 
Reported-by: Matteo Croce 
Tested-by: Eric Whitney 
Suggested-by: Eric Whitney 
Signed-off-by: Theodore Ts'o

ext4: disable synchronous transaction batching if max_batch_time==0

2014-07-05T23:18:22+00:00

The mount manpage says of the max_batch_time option,

	This optimization can be turned off entirely
	by setting max_batch_time to 0.

But the code doesn't do that.  So fix the code to do
that.

Signed-off-by: Eric Sandeen 
Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org

ext4: clarify error count warning messages

2014-07-05T22:40:52+00:00

Make it clear that values printed are times, and that it is error
since last fsck. Also add note about fsck version required.

Signed-off-by: Pavel Machek 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Andreas Dilger 
Cc: stable@vger.kernel.org

ext4: add missing BUFFER_TRACE before ext4_journal_get_write_access

2014-05-13T02:06:43+00:00

Make them more consistently

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

ext4: remove unnecessary double parentheses

2014-05-12T16:55:07+00:00

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

ext4: make local functions static

2014-05-12T14:50:23+00:00

I have been running make namespacecheck to look for unneeded globals, and
found these in ext4.

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

ext4: find the group descriptors on a 1k-block bigalloc,meta_bg filesystem

2014-05-12T14:06:27+00:00

On a filesystem with a 1k block size, the group descriptors live in
block 2, not block 1.  If the filesystem has bigalloc,meta_bg set,
however, the calculation of the group descriptor table location does
not take this into account and returns the wrong block number.  Fix
the calculation to return the correct value for this case.

Signed-off-by: Darrick J. Wong 
Signed-off-by: "Theodore Ts'o"

ext4: add a new spinlock i_raw_lock to protect the ext4's raw inode

2014-04-21T18:37:55+00:00

To avoid potential data races, use a spinlock which protects the raw
(on-disk) inode.

Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Jan Kara