Return-Path: Received: from mail-io0-f196.google.com ([209.85.223.196]:37687 "EHLO mail-io0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752478AbdI2VvZ (ORCPT ); Fri, 29 Sep 2017 17:51:25 -0400 Received: by mail-io0-f196.google.com with SMTP id 93so486046iol.4 for ; Fri, 29 Sep 2017 14:51:25 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20170928180703.GE10182@parsley.fieldses.org> References: <20170928172945.50780-1-kolga@netapp.com> <20170928172945.50780-6-kolga@netapp.com> <20170928180703.GE10182@parsley.fieldses.org> From: Olga Kornievskaia Date: Fri, 29 Sep 2017 17:51:23 -0400 Message-ID: Subject: Re: [PATCH v4 05/10] NFSD first draft of async copy To: "J. Bruce Fields" Cc: Olga Kornievskaia , linux-nfs Content-Type: text/plain; charset="UTF-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, Sep 28, 2017 at 2:07 PM, J. Bruce Fields wrote: > 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. 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. > > I don't think you need to do this--just call vfs_copy_file_range() > directly, as nfsd_copy_file_range does. > > The 4MB chunking was only there to prevent a synchronous copy from > taking too long, which isn't an issue in the async case. Before I remove the loop, the other reason I kept the loop was for a meaningful OFFLOAD_STATUS. Without the loop, any query for the OFFLOAD_STATUS would either return 0 or if it's really really really really lucky then it might return full-bytes copy value. There will never be an intermediate reply. I kept the loop and kept track of bytes copied so far for the status query. > > --b. > >> 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 >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html