Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:36864 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750819AbdI1SQT (ORCPT ); Thu, 28 Sep 2017 14:16:19 -0400 Date: Thu, 28 Sep 2017 14:16:13 -0400 From: "J. Bruce Fields" To: Olga Kornievskaia Cc: linux-nfs@vger.kernel.org Subject: Re: [PATCH v4 05/10] NFSD first draft of async copy Message-ID: <20170928181612.GF10182@parsley.fieldses.org> References: <20170928172945.50780-1-kolga@netapp.com> <20170928172945.50780-6-kolga@netapp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20170928172945.50780-6-kolga@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, Sep 28, 2017 at 01:29:40PM -0400, Olga Kornievskaia wrote: > Asynchronous copies are handled by a single threaded workqueue. > If we get asynchronous request, make sure to copy the needed > arguments/state from the stack before starting the copy. I'm worried by those copies--I suspect you want to be taking actual references (so, bumping reference counts) to the clp and the filehandles, not just copying pointers. --b. > Then > queue work and reply back to the client indicating copy is > asynchronous. > > nfsd_copy_file_range() will copy in 4MBchunk so do a loop over > the total number of bytes need to copy. In case a failure > happens in the middle, we can return an error as well as how > much we copied so far. Once done creating a workitem for the > callback workqueue and send CB_OFFLOAD with the results. > > Signed-off-by: Olga Kornievskaia > --- > fs/nfsd/nfs4proc.c | 164 ++++++++++++++++++++++++++++++++++++++++++++++------ > fs/nfsd/nfs4state.c | 9 ++- > fs/nfsd/state.h | 2 + > fs/nfsd/xdr4.h | 7 +++ > 4 files changed, 162 insertions(+), 20 deletions(-) > > diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c > index 11ade90..de21b1a 100644 > --- a/fs/nfsd/nfs4proc.c > +++ b/fs/nfsd/nfs4proc.c > @@ -76,6 +76,21 @@ > { } > #endif > > +static struct workqueue_struct *copy_wq; > + > +int nfsd4_create_copy_queue(void) > +{ > + copy_wq = create_singlethread_workqueue("nfsd4_copy"); > + if (!copy_wq) > + return -ENOMEM; > + return 0; > +} > + > +void nfsd4_destroy_copy_queue(void) > +{ > + destroy_workqueue(copy_wq); > +} > + > #define NFSDDBG_FACILITY NFSDDBG_PROC > > static u32 nfsd_attrmask[] = { > @@ -1085,37 +1100,148 @@ static int fill_in_write_vector(struct kvec *vec, struct nfsd4_write *write) > out: > return status; > } > +static void nfsd4_cb_offload_release(struct nfsd4_callback *cb) > +{ > + struct nfsd4_copy *copy = container_of(cb, struct nfsd4_copy, cp_cb); > + > + kfree(copy); > +} > + > +static int nfsd4_cb_offload_done(struct nfsd4_callback *cb, > + struct rpc_task *task) > +{ > + return 1; > +} > + > +static const struct nfsd4_callback_ops nfsd4_cb_offload_ops = { > + .release = nfsd4_cb_offload_release, > + .done = nfsd4_cb_offload_done > +}; > + > +static int nfsd4_init_copy_res(struct nfsd4_copy *copy, bool sync) > +{ > + memcpy(©->cp_res.cb_stateid, ©->cp_dst_stateid, > + sizeof(copy->cp_dst_stateid)); > + copy->cp_res.wr_stable_how = NFS_UNSTABLE; > + copy->cp_consecutive = 1; > + copy->cp_synchronous = sync; > + gen_boot_verifier(©->cp_res.wr_verifier, copy->net); > + > + return nfs_ok; > +} > + > +static int _nfsd_copy_file_range(struct nfsd4_copy *copy) > +{ > + ssize_t bytes_copied = 0; > + size_t bytes_total = copy->cp_count; > + size_t bytes_to_copy; > + u64 src_pos = copy->cp_src_pos; > + u64 dst_pos = copy->cp_dst_pos; > + > + do { > + bytes_to_copy = min_t(u64, bytes_total, MAX_RW_COUNT); > + bytes_copied = nfsd_copy_file_range(copy->fh_src, src_pos, > + copy->fh_dst, dst_pos, bytes_to_copy); > + if (bytes_copied <= 0) > + break; > + bytes_total -= bytes_copied; > + copy->cp_res.wr_bytes_written += bytes_copied; > + src_pos += bytes_copied; > + dst_pos += bytes_copied; > + } while (bytes_total > 0 && !copy->cp_synchronous); > + return bytes_copied; > +} > + > +static int nfsd4_do_copy(struct nfsd4_copy *copy, bool sync) > +{ > + __be32 status; > + ssize_t bytes; > + > + bytes = _nfsd_copy_file_range(copy); > + if (bytes < 0) > + status = nfserrno(bytes); > + else > + status = nfsd4_init_copy_res(copy, sync); > + > + fput(copy->fh_src); > + fput(copy->fh_dst); > + return status; > +} > + > +static void dup_copy_fields(struct nfsd4_copy *src, struct nfsd4_copy *dst) > +{ > + memcpy(&dst->cp_src_stateid, &src->cp_src_stateid, sizeof(stateid_t)); > + memcpy(&dst->cp_dst_stateid, &src->cp_dst_stateid, sizeof(stateid_t)); > + dst->cp_src_pos = src->cp_src_pos; > + dst->cp_dst_pos = src->cp_dst_pos; > + dst->cp_count = src->cp_count; > + dst->cp_consecutive = src->cp_consecutive; > + dst->cp_synchronous = src->cp_synchronous; > + memcpy(&dst->cp_res, &src->cp_res, sizeof(src->cp_res)); > + /* skipping nfsd4_callback */ > + memcpy(&dst->fh, &src->fh, sizeof(src->fh)); > + dst->fh = src->fh; > + dst->cp_clp = src->cp_clp; > + dst->fh_src = src->fh_src; > + dst->fh_dst = src->fh_dst; > + dst->net = src->net; > +} > + > +static void nfsd4_do_async_copy(struct work_struct *work) > +{ > + struct nfsd4_copy *copy = > + container_of(work, struct nfsd4_copy, cp_work); > + struct nfsd4_copy *cb_copy; > + > + copy->nfserr = nfsd4_do_copy(copy, 0); > + cb_copy = kzalloc(sizeof(struct nfsd4_copy), GFP_KERNEL); > + if (!cb_copy) > + goto out; > + memcpy(&cb_copy->cp_res, ©->cp_res, sizeof(copy->cp_res)); > + cb_copy->cp_clp = copy->cp_clp; > + cb_copy->nfserr = copy->nfserr; > + memcpy(&cb_copy->fh, ©->fh, sizeof(copy->fh)); > + nfsd4_init_cb(&cb_copy->cp_cb, cb_copy->cp_clp, > + &nfsd4_cb_offload_ops, NFSPROC4_CLNT_CB_OFFLOAD); > + nfsd4_run_cb(&cb_copy->cp_cb); > +out: > + kfree(copy); > +} > > static __be32 > nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, > union nfsd4_op_u *u) > { > struct nfsd4_copy *copy = &u->copy; > - struct file *src, *dst; > __be32 status; > - ssize_t bytes; > > - status = nfsd4_verify_copy(rqstp, cstate, ©->cp_src_stateid, &src, > - ©->cp_dst_stateid, &dst); > + status = nfsd4_verify_copy(rqstp, cstate, ©->cp_src_stateid, > + ©->fh_src, ©->cp_dst_stateid, > + ©->fh_dst); > if (status) > goto out; > > - bytes = nfsd_copy_file_range(src, copy->cp_src_pos, > - dst, copy->cp_dst_pos, copy->cp_count); > - > - if (bytes < 0) > - status = nfserrno(bytes); > - else { > - copy->cp_res.wr_bytes_written = bytes; > - copy->cp_res.wr_stable_how = NFS_UNSTABLE; > - copy->cp_consecutive = 1; > - copy->cp_synchronous = 1; > - gen_boot_verifier(©->cp_res.wr_verifier, SVC_NET(rqstp)); > - status = nfs_ok; > + copy->cp_clp = cstate->clp; > + memcpy(©->fh, &cstate->current_fh.fh_handle, > + sizeof(struct knfsd_fh)); > + copy->net = SVC_NET(rqstp); > + if (!copy->cp_synchronous) { > + struct nfsd4_copy *async_copy; > + > + status = nfsd4_init_copy_res(copy, 0); > + async_copy = kzalloc(sizeof(struct nfsd4_copy), GFP_KERNEL); > + if (!async_copy) { > + status = nfserrno(-ENOMEM); > + goto out; > + } > + dup_copy_fields(copy, async_copy); > + memcpy(©->cp_res.cb_stateid, ©->cp_dst_stateid, > + sizeof(copy->cp_dst_stateid)); > + INIT_WORK(&async_copy->cp_work, nfsd4_do_async_copy); > + queue_work(copy_wq, &async_copy->cp_work); > + } else { > + status = nfsd4_do_copy(copy, 1); > } > - > - fput(src); > - fput(dst); > out: > return status; > } > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index 0c04f81..fe6f275 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -7033,8 +7033,14 @@ static int nfs4_state_create_net(struct net *net) > goto out_free_laundry; > > set_max_delegations(); > - return 0; > > + ret = nfsd4_create_copy_queue(); > + if (ret) > + goto out_free_callback; > + > + return 0; > +out_free_callback: > + nfsd4_destroy_callback_queue(); > out_free_laundry: > destroy_workqueue(laundry_wq); > out_cleanup_cred: > @@ -7097,6 +7103,7 @@ static int nfs4_state_create_net(struct net *net) > destroy_workqueue(laundry_wq); > nfsd4_destroy_callback_queue(); > cleanup_callback_cred(); > + nfsd4_destroy_copy_queue(); > } > > static void > diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h > index f8b0210..b5358cf 100644 > --- a/fs/nfsd/state.h > +++ b/fs/nfsd/state.h > @@ -630,6 +630,8 @@ extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp, > extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(const char *name, > struct nfsd_net *nn); > extern bool nfs4_has_reclaimed_state(const char *name, struct nfsd_net *nn); > +extern int nfsd4_create_copy_queue(void); > +extern void nfsd4_destroy_copy_queue(void); > > struct nfs4_file *find_file(struct knfsd_fh *fh); > void put_nfs4_file(struct nfs4_file *fi); > diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h > index 9b0c099..f7a94d3 100644 > --- a/fs/nfsd/xdr4.h > +++ b/fs/nfsd/xdr4.h > @@ -529,6 +529,13 @@ struct nfsd4_copy { > struct nfsd4_callback cp_cb; > __be32 nfserr; > struct knfsd_fh fh; > + > + struct work_struct cp_work; > + struct nfs4_client *cp_clp; > + > + struct file *fh_src; > + struct file *fh_dst; > + struct net *net; > }; > > struct nfsd4_seek { > -- > 1.8.3.1 >