Adding support for remote blocking locks in virtiofs. Initially linux only supported the fcntl(SETLK) option. Now the fcntl(SETLKW) option is also supported. A guest issuing a fcntl(SETLKW) system call will block if another guest has already acquired the lock. Once the lock is available then the blocking guest will receive a notification, through the notification queue. Then the guest will unblock and acquire the lock. Vivek Goyal (3): virtiofs: Add an index to keep track of first request queue virtiofs: Add a virtqueue for notifications virtiofs: Support blocking posix locks (fcntl(F_SETLKW)) fs/fuse/virtio_fs.c | 290 +++++++++++++++++++++++++++++++-- include/uapi/linux/fuse.h | 7 + include/uapi/linux/virtio_fs.h | 5 + 3 files changed, 288 insertions(+), 14 deletions(-) -- 2.27.0
