HPFS: Introduce a global mutex and lock it on every callback from VFS.

Introduce a global mutex and lock it on every callback from VFS.

Performance doesn't matter, reviewing the whole code for locking correctness
would be too complicated, so simply lock it all.

Signed-off-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --cc fs/hpfs/buffer.c
Simple merge

diff --cc fs/hpfs/file.c
Simple merge

diff --cc fs/hpfs/hpfs_fn.h
Simple merge

diff --cc fs/hpfs/super.c
Simple merge