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 <kolga@xxxxxxxxxx>
> ---
> 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
>
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