On Tue, Oct 24, 2017 at 1:47 PM, Olga Kornievskaia <kolga@xxxxxxxxxx> wrote: > To do asynchronous copies, NFSD creates a new kthread to handle the request. > Upon receiving the COPY, it generates a unique copy stateid (stored in a > global list for keeping track of state for OFFLOAD_STATUS to be queried by), > starts the thread, and replies back to the client. nfsd4_copy arguments that > are allocated on the stack are copies for the kthread. > > For the async copy handler, copy is done in the loop for the requested > number of bytes. If an error is encountered and partial copy has happened, > a successful partial copy is returned in the CB_OFFLOAD. vfs_copy_file_range > is called with 4MB chunks for both async and sync, allowing for 4MB > granularity of OFFLOAD_STATUS queiry. Once copy is done, the results are > queued for the callback workqueue and sent via CB_OFFLOAD. > > When the server received an OFFLOAD_CANCEL, it will find the kthread running > the copy and will send a SIGPENDING and kthread_stop() and it will interrupt > the ongoing do_splice() and once vfs returns we are choosing not to send > the CB_OFFLOAD back to the client. > > When the server receives an OFFLOAD_STATUS, it will find the kthread running > the copy and will locate within the copy state the current number of bytes > copied so far. > > v6: > 1. if an error occured and partial bytes were copied, don't return the error > and instead return the successful partial copy. > 2. OFFLOAD_STATUS locates the on-going copy and looks up the number of bytes > copied so far. > > Olga Kornievskaia (10): > NFSD CB_OFFLOAD xdr > NFSD OFFLOAD_STATUS xdr > NFSD OFFLOAD_CANCEL xdr > NFSD xdr callback stateid in async COPY reply > NFSD first draft of async copy > NFSD return nfs4_stid in nfs4_preprocess_stateid_op > NFSD create new stateid for async copy > NFSD handle OFFLOAD_CANCEL op > NFSD support OFFLOAD_STATUS > NFSD stop queued async copies on client shutdown > > fs/nfsd/netns.h | 8 ++ > fs/nfsd/nfs4callback.c | 97 +++++++++++++++ > fs/nfsd/nfs4proc.c | 316 ++++++++++++++++++++++++++++++++++++++++++++----- > fs/nfsd/nfs4state.c | 77 +++++++++++- > fs/nfsd/nfs4xdr.c | 50 ++++++-- > fs/nfsd/nfsctl.c | 1 + > fs/nfsd/state.h | 21 +++- > fs/nfsd/xdr4.h | 28 +++++ > fs/nfsd/xdr4cb.h | 10 ++ > 9 files changed, 571 insertions(+), 37 deletions(-) Bruce, any comments on this version? -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
