block: remove CONFIG_LBDAF

Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit
architectures.  These types are required to support block device and/or
file sizes larger than 2 TiB, and have generally defaulted to on for
a long time.  Enabling the option only increases the i386 tinyconfig
size by 145 bytes, and many data structures already always use
64-bit values for their in-core and on-disk data structures anyway,
so there should not be a large change in dynamic memory usage either.

Dropping this option removes a somewhat weird non-default config that
has cause various bugs or compiler warnings when actually used.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/stack.c b/fs/stack.c
index a54e33e..664ed35 100644
--- a/fs/stack.c
+++ b/fs/stack.c
@@ -21,11 +21,10 @@ void fsstack_copy_inode_size(struct inode *dst, struct inode *src)
 	i_size = i_size_read(src);
 
 	/*
-	 * But if CONFIG_LBDAF (on 32-bit), we ought to make an effort to
-	 * keep the two halves of i_blocks in sync despite SMP or PREEMPT -
-	 * though stat's generic_fillattr() doesn't bother, and we won't be
-	 * applying quotas (where i_blocks does become important) at the
-	 * upper level.
+	 * But on 32-bit, we ought to make an effort to keep the two halves of
+	 * i_blocks in sync despite SMP or PREEMPT - though stat's
+	 * generic_fillattr() doesn't bother, and we won't be applying quotas
+	 * (where i_blocks does become important) at the upper level.
 	 *
 	 * We don't actually know what locking is used at the lower level;
 	 * but if it's a filesystem that supports quotas, it will be using
@@ -44,9 +43,9 @@ void fsstack_copy_inode_size(struct inode *dst, struct inode *src)
 	 * include/linux/fs.h).  We don't necessarily hold i_mutex when this
 	 * is called, so take i_lock for that case.
 	 *
-	 * And if CONFIG_LBDAF (on 32-bit), continue our effort to keep the
-	 * two halves of i_blocks in sync despite SMP or PREEMPT: use i_lock
-	 * for that case too, and do both at once by combining the tests.
+	 * And if on 32-bit, continue our effort to keep the two halves of
+	 * i_blocks in sync despite SMP or PREEMPT: use i_lock  for that case
+	 * too, and do both at once by combining the tests.
 	 *
 	 * There is none of this locking overhead in the 64-bit case.
 	 */