On Wed, 2023-05-17 at 16:38 -0700, Dai Ngo wrote: > NFSD: add support for NFSv4 write delegation > > The NFSv4 server currently supports read delegation using VFS lease > which is implemented using file_lock. > > This patch series add write delegation support for NFSv4 server by: > > . remove the check for F_WRLCK in generic_add_lease to allow > file_lock to be used for write delegation. > > . grant write delegation for OPEN with NFS4_SHARE_ACCESS_WRITE > if there is no conflict with other OPENs. > > Write delegation conflict with another OPEN, REMOVE, RENAME and SETATTR > are handled the same as read delegation using notify_change, try_break_deleg. > > Changes since v1: > > [PATCH 3/4] NFSD: add supports for CB_GETATTR callback > - remove WARN_ON_ONCE from encode_bitmap4 > - replace decode_bitmap4 with xdr_stream_decode_uint32_array > - replace xdr_inline_decode and xdr_decode_hyper in decode_cb_getattr > with xdr_stream_decode_u64. Also remove the un-needed likely(). > - modify signature of encode_cb_getattr4args to take pointer to > nfs4_cb_fattr > - replace decode_attr_length with xdr_stream_decode_u32 > - rename decode_cb_getattr to decode_cb_fattr4 > - fold the initialization of cb_cinfo and cb_fsize into decode_cb_fattr4 > - rename ncf_cb_cinfo to ncf_cb_change to avoid confusion of cindo usage > in fs/nfsd/nfs4xdr.c > - correct NFS4_dec_cb_getattr_sz and update size description > > [PATCH 4/4] NFSD: handle GETATTR conflict with write delegation > - change nfs4_handle_wrdeleg_conflict returns __be32 to fix test robot > - change ncf_cb_cinfo to ncf_cb_change to avoid confusion of cindo usage > in fs/nfsd/nfs4xdr.c > > Changes since v2: > > [PATCH 2/4] NFSD: enable support for write delegation > - rename 'deleg' to 'dl_type' in nfs4_set_delegation > - remove 'wdeleg' in nfs4_open_delegation > > - drop [PATCH 3/4] NFSD: add supports for CB_GETATTR callback > and [PATCH 4/4] NFSD: handle GETATTR conflict with write delegation > for futher clarification of the benefits of using CB_GETATTR > for handling GETATTR from the 2nd client > Pretty straightforward. Not as useful (IMO) without CB_GETATTR, since even a stray 'ls -l' in the parent directory will cause the delegation to be recalled, but it's a reasonable first step. Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
