linux-toradex.git/fs/xfs/xfs_dir2_node.c, branch v3.10.41

xfs: fix dir3 freespace block corruption

2013-05-30T22:22:54+00:00

When the directory freespace index grows to a second block (2017
4k data blocks in the directory), the initialisation of the second
new block header goes wrong. The write verifier fires a corruption
error indicating that the block number in the header is zero. This
was being tripped by xfs/110.

The problem is that the initialisation of the new block is done just
fine in xfs_dir3_free_get_buf(), but the caller then users a dirv2
structure to zero on-disk header fields that xfs_dir3_free_get_buf()
has already zeroed. These lined up with the block number in the dir
v3 header format.

While looking at this, I noticed that the struct xfs_dir3_free_hdr()
had 4 bytes of padding in it that wasn't defined as padding or being
zeroed by the initialisation. Add a pad field declaration and fully
zero the on disk and in-core headers in xfs_dir3_free_get_buf() so
that this is never an issue in the future. Note that this doesn't
change the on-disk layout, just makes the 32 bits of padding in the
layout explicit.

Signed-off-by: Dave Chinner 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers 

(cherry picked from commit 5ae6e6a401957698f2bd8c9f4a86d86d02199fea)

xfs: introduce CONFIG_XFS_WARN

2013-05-07T23:45:36+00:00

Running a CONFIG_XFS_DEBUG kernel in production environments is not
the best idea as it introduces significant overhead, can change
the behaviour of algorithms (such as allocation) to improve test
coverage, and (most importantly) panic the machine on non-fatal
errors.

There are many cases where all we want to do is run a
kernel with more bounds checking enabled, such as is provided by the
ASSERT() statements throughout the code, but without all the
potential overhead and drawbacks.

This patch converts all the ASSERT statements to evaluate as
WARN_ON(1) statements and hence if they fail dump a warning and a
stack trace to the log. This has minimal overhead and does not
change any algorithms, and will allow us to find strange "out of
bounds" problems more easily on production machines.

There are a few places where assert statements contain debug only
code. These are converted to be debug-or-warn only code so that we
still get all the assert checks in the code.

Signed-off-by: Dave Chinner 
Reviewed-by: Brian Foster 
Signed-off-by: Ben Myers

xfs: buffer type overruns blf_flags field

2013-04-27T18:01:58+00:00

The buffer type passed to log recvoery in the buffer log item
overruns the blf_flags field. I had assumed that flags field was a
32 bit value, and it turns out it is a unisgned short. Therefore
having 19 flags doesn't really work.

Convert the buffer type field to numeric value, and use the top 5
bits of the flags field for it. We currently have 17 types of
buffers, so using 5 bits gives us plenty of room for expansion in
future....

Signed-off-by: Dave Chinner 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: add buffer types to directory and attribute buffers

2013-04-27T18:01:06+00:00

Add buffer types to the buffer log items so that log recovery can
validate the buffers and calculate CRCs correctly after the buffers
are recovered.

Signed-off-by: Dave Chinner 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: add CRCs to dir2/da node blocks

2013-04-27T17:33:38+00:00

Signed-off-by: Dave Chinner 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: add CRC checking to dir2 leaf blocks

2013-04-27T17:19:53+00:00

This addition follows the same pattern as the dir2 block CRCs.
Seeing as both LEAF1 and LEAFN types need to changed at the same
time, this is a pretty large amount of change. leaf block headers
need to be abstracted away from the on-disk structures (struct
xfs_dir3_icleaf_hdr), as do the base leaf entry locations.

This header abstract allows the in-core header and leaf entry
location to be passed around instead of the leaf block itself. This
saves a lot of converting individual variables from on-disk format
to host format where they are used, so there's a good chance that
the compiler will be able to produce much more optimal code as it's
not having to byteswap variables all over the place.

Signed-off-by: Dave Chinner 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: add CRC checking to dir2 data blocks

2013-04-27T17:00:00+00:00

This addition follows the same pattern as the dir2 block CRCs.

Signed-off-by: Dave Chinner 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: add CRC checking to dir2 free blocks

2013-04-27T16:58:16+00:00

This addition follows the same pattern as the dir2 block CRCs, but
with a few differences. The main difference is that the free block
header is different between the v2 and v3 formats, so an "in-core"
free block header has been added and _todisk/_from_disk functions
used to abstract the differences in structure format from the code.
This is similar to the on-disk superblock versus the in-core
superblock setup. The in-core strucutre is populated when the buffer
is read from disk, all the in memory checks and modifications are
done on the in-core version of the structure which is written back
to the buffer before the buffer is logged.

Signed-off-by: Dave Chinner 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: add CRC checks to block format directory blocks

2013-04-27T16:51:56+00:00

Now that directory buffers are made from a single struct xfs_buf, we
can add CRC calculation and checking callbacks. While there, add all
the fields to the on disk structures for future functionality such
as d_type support, uuids, block numbers, owner inode, etc.

To distinguish between the different on disk formats, change the
magic numbers for the new format directory blocks.

Signed-off-by: Dave Chinner 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: convert buffer verifiers to an ops structure.

2012-11-16T03:35:12+00:00

To separate the verifiers from iodone functions and associate read
and write verifiers at the same time, introduce a buffer verifier
operations structure to the xfs_buf.

This avoids the need for assigning the write verifier, clearing the
iodone function and re-running ioend processing in the read
verifier, and gets rid of the nasty "b_pre_io" name for the write
verifier function pointer. If we ever need to, it will also be
easier to add further content specific callbacks to a buffer with an
ops structure in place.

We also avoid needing to export verifier functions, instead we
can simply export the ops structures for those that are needed
outside the function they are defined in.

This patch also fixes a directory block readahead verifier issue
it exposed.

This patch also adds ops callbacks to the inode/alloc btree blocks
initialised by growfs. These will need more work before they will
work with CRCs.

Signed-off-by: Dave Chinner 
Reviewed-by: Phil White 
Signed-off-by: Ben Myers