Btrfs-progs: add skinny metadata support to progs

This fixes up the progs to properly deal with skinny metadata.  This adds the -x
option to mkfs and btrfstune for enabling the skinny metadata option.  This also
makes changes to fsck so it can properly deal with the skinny metadata entries.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs-progs: fix segfault when using tools fs with tree log

We just free the log root after we set it up when we open a ctree in the tools.
This isn't nice, it makes double free's and leaks eb's, makes segfaults with
btrfs-image.  So fix this to be correct, and fix the cleanup if the buffer is
not uptodate.  With this fix I no longer segfault trying to do btrfs-image on a
file system with a log tree.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs-progs: fix memory leaks on cleanup

I've been working on btrfs-image and I kept seeing these leaks pop up on
valgrind so I'm just fixing them.  We don't properly cleanup the device cache,
the chunk tree mapping cache, or the space infos on close.  With this patch
valgrind doesn't complain about any memory leaks running btrfs-image.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs-progs: cleanup error handling in btrfs-image

We use BUG_ON() everywhere in btrfs-image.  When users are going to use this
command things are pretty dire, so I'd rather have really good error messages so
I know what happened rather than figure out which one of the 20 BUG_ON()'s made
the stupid thing exit early.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs-progs: make btrfs-image copy the tree logs if they exist

Currently btrfs-image doesn't copy the tree logs, which doesn't help me when
we're trying to debug log replay bugs.  Since we don't have entries in the
extent root for the blocks we have to walk down all of the trees in order to
copy them.  With this patch I can image a file system with a tree log and it
works fine.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs-progs: make btrfs-image grab the free space cache

A lot of tree log replay bugs are because of strange space cache setups, so make
btrfs-image scrape the free space cache as well so we can better replicate what
a user is seeing if they have a tree log bug or anything related to free space
cache.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs-progs: make btrfs-image restore with a valid chunk tree

Previously btrfs-image would set a METADUMP flag and would make one big system
chunk to cover the entire file system in the super in order to get around the
unpleasant business of having to adjust the chunk tree.  This meant that you
could use the progs stuff on a restored file system, which is great for testing
btrfsck and other such things.  But we want to be able to run the tree log
replay on a file system that is not able to run the tree log replay.  So in
order to do this we need to fixup the super's chunk array and the chunk tree
itself.  This is pretty easy since we restore using the logical offsets of the
metadata, so we just have to set the chunk items to have 1 stripe and have the
stripes point at the primary device and then use the logical offset of the chunk
as the physical offset.  With this patch I can restore a file system image that
had a tree log and mount the file system and have the log be replayed
successfully.  This patch also gives you the -o option in case you want the old
restore way, in the case where we want to make sure the system chunks as they
were given to us are correct.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs-progs: add btrfs-crc tool

This tool can be used to compute btrfs' style crc32c checksums for filenames
as done by the kernel. Additionally, there is -c mode to do a brute force
search for file names with a given checksum.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Btrfs-image: add the ability to santize file names when making an image

We've had a few users who wouldn't (or couldn't) provide us btrfs-images because
we maintain the file names when making an image.  So introduce a sanitize
option.  There are two uses, one that is fast and the other that is dog slow.
The fast way just generates garbage that's equal in length to the original name.
The slow way will try and find a crc32c collision for the file name that is also
the same length.  Finding a crc32c collision for the file name "btrfs-progs" on
my box without CPU crc32c support takes a little more than 3 minutes, and a
little less than 2 minutes for my box that has CPU crc32c support, so it's a
lengthy and CPU intensive process.

The idea is that we use -s for most cases, and then only use -ss when we need
the file system tree to be somewhat sane.  I could probably do a better job
about finding collisions, but I'll have to revist that later.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs-progs: add support for the ENOSPC log

This adds support for the ENOSPC log incompat feature.  We can mkfs with the new
format and we'll read the block groups properly.  Support for clearing the log
will come later.

Signed-off-by: Josef Bacik <jbacik@fusionio.com>