Hi, I sent this as a PATCH now and drop the RFC. I got some review back from Jeff Layton and hope I was successful to follow it. There are still issues with lockd and asynchronous lock request but it will at least not directly crash when somebody is using nfs on top of GFS2. The issues are related to cancellation of locks/lockd decides to drop nlm_block for some reasons while pending request is happening. I did not change more documentation about the asynchronous lock request functionality to not confuse users. In my opinion there should be more documentation about what you SHOULD NOT do with this API. Otherwise I think the documentation is still correct. I will send a follow up patch to fsdevel to change all users using IS_SETLKW() to use FL_SLEEP to determine if it's blocking or non-blocking and send it to fsdevel as it was recommended. This will just be a grep and replace patch and look what happens. - Alex changes since v2: - remove B_PENDING_CALLBACK paragraph from commit msg. Was a leftover and I forgot to update the commit message. - change function name from export_op_support_safe_async_lock() to exportfs_lock_op_is_async() - change flag name from EXPORT_OP_SAFE_ASYNC_LOCK to EXPORT_OP_ASYNC_LOCK - add documentation for EXPORT_OP_ASYNC_LOCK to Documentation/filesystems/nfs/exporting.rst - add newline between function name and return type of exportfs_lock_op_is_async() - remove f_op->lock() check and mention it in Documentation/filesystems/nfs/exporting.rst to only use it with filesystems implementing their own ->lock() - add kdoc for exportfs_lock_op_is_async() changes since RFC: - drop the pending callback flag but introduce "lockd: don't call vfs_lock_file() for pending requests", see patch why I need it. - drop per nlm_block callback mutex - change async lock request documentation - use always FL_SLEEP to determine if it's blocking vs non-blocking in DLM Alexander Aring (7): lockd: introduce safe async lock op lockd: don't call vfs_lock_file() for pending requests lockd: fix race in async lock request handling lockd: add doc to enable EXPORT_OP_ASYNC_LOCK dlm: use fl_owner from lockd dlm: use FL_SLEEP to determine blocking vs non-blocking dlm: implement EXPORT_OP_ASYNC_LOCK Documentation/filesystems/nfs/exporting.rst | 7 ++++ fs/dlm/plock.c | 20 +++-------- fs/gfs2/export.c | 1 + fs/lockd/svclock.c | 38 ++++++++++++++------- fs/locks.c | 12 ++++--- fs/nfsd/nfs4state.c | 10 ++++-- fs/ocfs2/export.c | 1 + include/linux/exportfs.h | 14 ++++++++ 8 files changed, 67 insertions(+), 36 deletions(-) -- 2.31.1
