BKL: introduce CONFIG_BKL.

With all the patches we have queued in the BKL removal tree, only a
few dozen modules are left that actually rely on the BKL, and even
there are lots of low-hanging fruit. We need to decide what to do
about them, this patch illustrates one of the options:

Every user of the BKL is marked as 'depends on BKL' in Kconfig,
and the CONFIG_BKL becomes a user-visible option. If it gets
disabled, no BKL using module can be built any more and the BKL
code itself is compiled out.

The one exception is file locking, which is practically always
enabled and does a 'select BKL' instead. This effectively forces
CONFIG_BKL to be enabled until we have solved the fs/lockd
mess and can apply the patch that removes the BKL from fs/locks.c.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/Kconfig b/fs/Kconfig
index 3d185308ec88..65781de44fc0 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -50,6 +50,7 @@ endif # BLOCK
 config FILE_LOCKING
         bool "Enable POSIX file locking API" if EMBEDDED
         default y
+        select BKL # while lockd still uses it.
         help
           This option enables standard file locking support, required
           for filesystems like NFS and for the flock() system