This patch series adds support for NFSv4.2 copy offload feature allowing copy between two different NFS servers. This functionality depends on the VFS ability to support generic copy_file_range() where a copy is done between an NFS file and a local file system. This is on top of Amir's VFS generic copy offload series. This feature is enabled by the kernel module parameter -- inter_copy_offload_enable -- and by default is disabled. There is also a kernel compile configuration of NFSD_V4_2_INTER_SSC that adds dependency on the NFS client side functions called from the server. These patches work on top of existing async intra copy offload patches. For the "inter" SSC, the implementation only supports asynchronous inter copy. On the source server, upon receiving a COPY_NOTIFY, it generate a unique stateid that's kept in the global list. Upon receiving a READ with a stateid, the code checks the normal list of open stateid and now additionally, it'll check the copy state list as well before deciding to either fail with BAD_STATEID or find one that matches. The stored stateid is only valid to be used for the first time with a choosen lease period (90s currently). When the source server received an OFFLOAD_CANCEL, it will remove the stateid from the global list. Otherwise, the copy stateid is removed upon the removal of its "parent" stateid (open/lock/delegation stateid). On the destination server, upon receiving a COPY request, the server establishes the necessary clientid/session with the source server. It calls into the NFS client code to establish the necessary open stateid, filehandle, file description (without doing an NFS open). Then the server calls into the copy_file_range() to preform the copy where the source file will issue NFS READs and then do local file system writes (this depends on the VFS ability to do cross device copy_file_range(). v4: --- allowing for synchronous inter server-to-server copy --- added missing offload_cancel on the source server Already presented numbers for performance improvement for large file transfer but here are times for copying linux kernel tree (which is mostly small files): -- regular cp 6m1s (intra) -- copy offload cp 4m11s (intra) -- benefit of using copy offload with small copies using sync copy -- regular cp 6m9s (inter) -- copy offload cp 6m3s (inter) -- same performance as traditional as for most it fallback to traditional copy offload Olga Kornievskaia (8): NFSD fill-in netloc4 structure NFSD add ca_source_server<> to COPY NFSD return nfs4_stid in nfs4_preprocess_stateid_op NFSD add COPY_NOTIFY operation NFSD check stateids against copy stateids NFSD generalize nfsd4_compound_state flag names NFSD: allow inter server COPY to have a STALE source server fh NFSD add nfs4 inter ssc to nfsd4_copy fs/nfsd/Kconfig | 10 ++ fs/nfsd/nfs4proc.c | 434 +++++++++++++++++++++++++++++++++++++++++++++++----- fs/nfsd/nfs4state.c | 135 ++++++++++++++-- fs/nfsd/nfs4xdr.c | 172 ++++++++++++++++++++- fs/nfsd/nfsd.h | 32 ++++ fs/nfsd/nfsfh.h | 5 +- fs/nfsd/nfssvc.c | 6 + fs/nfsd/state.h | 25 ++- fs/nfsd/xdr4.h | 37 ++++- 9 files changed, 790 insertions(+), 66 deletions(-) -- 1.8.3.1
