Al pointed out that we can just toss out the old name on a device and add a
new one arbitrarily, so anybody who uses device->name in printk could
possibly use free'd memory.  Instead of adding locking around all of this he
suggested doing it with RCU, so I've introduced a struct rcu_string that
does just that and have gone through and protected all accesses to
device->name that aren't under the uuid_mutex with rcu_read_lock().  This
protects us and I will use it for dealing with removing the device that we
used to mount the file system in a later patch.  Thanks,
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <josef@redhat.com>

During unmount, it could happen that the integrity checker printed a
warning message "attempt to free ... on umount which is not yet iodone"
which turned out to be a false positive.
Signed-off-by: NStefan Behrens <sbehrens@giantdisaster.de>

If a file_extent_item was located at the very end of a leaf and there was
not enough space to hold a full item, but there was enough space to hold
one of type BTRFS_FILE_EXTENT_INLINE or PREALLOC, and it was only such a
short item, a warning was printed anyway. This check is now fixed.
Signed-off-by: NStefan Behrens <sbehrens@giantdisaster.de>

The integrity checker used to be coded for nodesize == leafsize ==
sectorsize == PAGE_CACHE_SIZE.
This is now changed to support sizes for nodesize and leafsize which are
N * PAGE_CACHE_SIZE.
Signed-off-by: NStefan Behrens <sbehrens@giantdisaster.de>

The enospc tracing code added some interesting uses of
u64 pointer casts.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Once should be enough.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

There have been 4 warnings on 32-bit build, they are herewith fixed.
Signed-off-by: NStefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

The two files added in this patch contain all the code that is
required to implement the integrity checks.
Signed-off-by: NStefan Behrens <sbehrens@giantdisaster.de>