This patch try to fix the building error on MIPS. The reason is MIPS
has already defined the PTR macro, which conflicts with the PTR macro
in include/uapi/linux/bcache.h.

[fixed by mlyle: corrected a line-length issue]

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Many user space API headers are missing licensing information, which
makes it hard for compliance tools to determine the correct license.

By default are files without license information under the default
license of the kernel, which is GPLV2.  Marking them GPLV2 would exclude
them from being included in non GPLV2 code, which is obviously not
intended. The user space API headers fall under the syscall exception
which is in the kernels COPYING file:

   NOTE! This copyright does *not* cover user programs that use kernel
   services by normal system calls - this is merely considered normal use
   of the kernel, and does *not* fall under the heading of "derived work".

otherwise syscall usage would not be possible.

Update the files which contain no license information with an SPDX
license identifier.  The chosen identifier is 'GPL-2.0 WITH
Linux-syscall-note' which is the officially assigned identifier for the
Linux syscall exception.  SPDX license identifiers are a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.  See the previous patch in this series for the
methodology of how this patch was researched.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Some files will be exported after a following patch. 0-day tests report the
following warning/error:
./usr/include/linux/bcache.h:8: include of <linux/types.h> is preferred over <asm/types.h>
./usr/include/linux/bcache.h:11: found __[us]{8,16,32,64} type without #include <linux/types.h>
./usr/include/linux/qrtr.h:8: found __[us]{8,16,32,64} type without #include <linux/types.h>
./usr/include/linux/cryptouser.h:39: found __[us]{8,16,32,64} type without #include <linux/types.h>
./usr/include/linux/pr.h:14: found __[us]{8,16,32,64} type without #include <linux/types.h>
./usr/include/linux/btrfs_tree.h:337: found __[us]{8,16,32,64} type without #include <linux/types.h>
./usr/include/rdma/bnxt_re-abi.h:45: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Helper function to explicitly check how much space is free in a btree node

Signed-off-by: Kent Overstreet <kmo@daterainc.com>

More refactoring:

node() -> bset_bkey_idx()
end() -> bset_bkey_last()

Signed-off-by: Kent Overstreet <kmo@daterainc.com>

Now, the on disk data structures are in a header that can be exported to
userspace - and having them all centralized is nice too.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>