From e0639dc5805a9d4faaa2c07ad98fa853b9529dd3 Mon Sep 17 00:00:00 2001 From: Olga Kornievskaia Date: Fri, 20 Jul 2018 18:19:20 -0400 Subject: NFSD introduce async copy feature Upon receiving a request for async copy, create a new kthread. If we get asynchronous request, make sure to copy the needed arguments/state from the stack before starting the copy. Then start the thread and reply back to the client indicating copy is asynchronous. nfsd_copy_file_range() will copy in a loop over the total number of bytes is needed to copy. In case a failure happens in the middle, we ignore the error and return how much we copied so far. Once done creating a workitem for the callback workqueue and send CB_OFFLOAD with the results. The lifetime of the copy stateid is bound to the vfs copy. This way we don't need to keep the nfsd_net structure for the callback. We could keep it around longer so that an OFFLOAD_STATUS that came late would still get results, but clients should be able to deal without that. We handle OFFLOAD_CANCEL by sending a signal to the copy thread and calling kthread_stop. A client should cancel any ongoing copies before calling DESTROY_CLIENT; if not, we return a CLIENT_BUSY error. If the client is destroyed for some other reason (lease expiration, or server shutdown), we must clean up any ongoing copies ourselves. Signed-off-by: Olga Kornievskaia [colin.king@canonical.com: fix leak in error case] [bfields@fieldses.org: remove signalling, merge patches] Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4xdr.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) (limited to 'fs/nfsd/nfs4xdr.c') diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index b78280a8af73..3de42a729093 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -4231,15 +4231,27 @@ nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr, #endif /* CONFIG_NFSD_PNFS */ static __be32 -nfsd42_encode_write_res(struct nfsd4_compoundres *resp, struct nfsd42_write_res *write) +nfsd42_encode_write_res(struct nfsd4_compoundres *resp, + struct nfsd42_write_res *write, bool sync) { __be32 *p; + p = xdr_reserve_space(&resp->xdr, 4); + if (!p) + return nfserr_resource; - p = xdr_reserve_space(&resp->xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE); + if (sync) + *p++ = cpu_to_be32(0); + else { + __be32 nfserr; + *p++ = cpu_to_be32(1); + nfserr = nfsd4_encode_stateid(&resp->xdr, &write->cb_stateid); + if (nfserr) + return nfserr; + } + p = xdr_reserve_space(&resp->xdr, 8 + 4 + NFS4_VERIFIER_SIZE); if (!p) return nfserr_resource; - *p++ = cpu_to_be32(0); p = xdr_encode_hyper(p, write->wr_bytes_written); *p++ = cpu_to_be32(write->wr_stable_how); p = xdr_encode_opaque_fixed(p, write->wr_verifier.data, @@ -4253,7 +4265,8 @@ nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr, { __be32 *p; - nfserr = nfsd42_encode_write_res(resp, ©->cp_res); + nfserr = nfsd42_encode_write_res(resp, ©->cp_res, + copy->cp_synchronous); if (nfserr) return nfserr; -- cgit v1.2.3