On Fri, Feb 16, 2018 at 12:28:19PM -0500, Olga Kornievskaia wrote:
> On Tue, Oct 24, 2017 at 1:47 PM, Olga Kornievskaia <kolga@xxxxxxxxxx> wrote:
> > Upon receiving OFFLOAD_CANCEL search the list of copy stateids,
> > if found then set the SIGPENDING signal so that do_splice stops
> > copying and also send kthread_stop to the copy thread to stop
> > and wait for it. Take a reference on the copy from the
> > offload_cancel thread so that it won't go away while we are
> > trying to process it. Server won't be sending CB_OFFLOAD to the
> > client since it received a cancel.
> >
> > Signed-off-by: Olga Kornievskaia <kolga@xxxxxxxxxx>
> > ---
> > fs/nfsd/nfs4proc.c | 46 ++++++++++++++++++++++++++++++++++++++++++++--
> > fs/nfsd/xdr4.h | 1 +
> > 2 files changed, 45 insertions(+), 2 deletions(-)
> >
> > diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> > index 6876080..3b0bb54 100644
> > --- a/fs/nfsd/nfs4proc.c
> > +++ b/fs/nfsd/nfs4proc.c
> > @@ -1097,6 +1097,14 @@ static int fill_in_write_vector(struct kvec *vec, struct nfsd4_write *write)
> > out:
> > return status;
> > }
> > +
> > +static void nfs4_put_copy(struct nfsd4_copy *copy)
> > +{
> > + if (!atomic_dec_and_test(©->refcount))
> > + return;
> > + kfree(copy);
> > +}
> > +
> > static void nfsd4_cb_offload_release(struct nfsd4_callback *cb)
> > {
> > struct nfsd4_copy *copy = container_of(cb, struct nfsd4_copy, cp_cb);
> > @@ -1134,6 +1142,8 @@ static int _nfsd_copy_file_range(struct nfsd4_copy *copy)
> > u64 dst_pos = copy->cp_dst_pos;
> >
> > do {
> > + if (signalled() || kthread_should_stop())
> > + return -1;
> > bytes_copied = nfsd_copy_file_range(copy->fh_src, src_pos,
> > copy->fh_dst, dst_pos, bytes_total);
> > if (bytes_copied <= 0)
> > @@ -1152,11 +1162,16 @@ static int nfsd4_do_copy(struct nfsd4_copy *copy, bool sync)
> > ssize_t bytes;
> >
> > bytes = _nfsd_copy_file_range(copy);
> > + if (signalled() || kthread_should_stop()) {
> > + status = -1;
> > + goto cleanup;
> > + }
> > if (bytes < 0 && !copy->cp_res.wr_bytes_written)
> > status = nfserrno(bytes);
> > else
> > status = nfsd4_init_copy_res(copy, sync);
> >
> > +cleanup:
> > fput(copy->fh_src);
> > fput(copy->fh_dst);
> > return status;
> > @@ -1194,7 +1209,7 @@ static void cleanup_async_copy(struct nfsd4_copy *copy)
> > list_del(©->copies);
> > spin_unlock(©->cp_clp->async_lock);
> > atomic_dec(©->cp_clp->cl_refcount);
> > - kfree(copy);
> > + nfs4_put_copy(copy);
> > }
> >
> > static int nfsd4_do_async_copy(void *data)
> > @@ -1203,6 +1218,9 @@ static int nfsd4_do_async_copy(void *data)
> > struct nfsd4_copy *cb_copy;
> >
> > copy->nfserr = nfsd4_do_copy(copy, 0);
> > + if (signalled() || kthread_should_stop())
> > + goto out;
> > +
> > cb_copy = kzalloc(sizeof(struct nfsd4_copy), GFP_KERNEL);
> > if (!cb_copy)
> > goto out;
> > @@ -1259,6 +1277,7 @@ static int nfsd4_do_async_copy(void *data)
> > memcpy(©->cp_res.cb_stateid, ©->cps->cp_stateid,
> > sizeof(copy->cps->cp_stateid));
> > dup_copy_fields(copy, async_copy);
> > + atomic_set(&async_copy->refcount, 1);
> > spin_lock(&async_copy->cp_clp->async_lock);
> > list_add(&async_copy->copies,
> > &async_copy->cp_clp->async_copies);
> > @@ -1285,7 +1304,30 @@ static int nfsd4_do_async_copy(void *data)
> > struct nfsd4_compound_state *cstate,
> > union nfsd4_op_u *u)
> > {
> > - return 0;
> > + struct nfsd4_offload_status *os = &u->offload_status;
> > + __be32 status = 0;
> > + struct nfsd4_copy *copy;
> > + bool found = false;
> > + struct nfs4_client *clp = cstate->clp;
> > +
> > + spin_lock(&clp->async_lock);
> > + list_for_each_entry(copy, &clp->async_copies, copies) {
> > + if (memcmp(©->cps->cp_stateid, &os->stateid,
> > + NFS4_STATEID_SIZE))
> > + continue;
> > + found = true;
> > + atomic_inc(©->refcount);
> > + break;
> > + }
> > + spin_unlock(&clp->async_lock);
> > + if (found) {
> > + set_tsk_thread_flag(copy->copy_task, TIF_SIGPENDING);
> > + kthread_stop(copy->copy_task);
> > + nfs4_put_copy(copy);
> > + } else
> > + status = nfserr_bad_stateid;
> > +
> > + return status;
> > }
> >
> > static __be32
> > diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
> > index 27bac6a..3127b58 100644
> > --- a/fs/nfsd/xdr4.h
> > +++ b/fs/nfsd/xdr4.h
> > @@ -540,6 +540,7 @@ struct nfsd4_copy {
> >
> > struct list_head copies;
> > struct task_struct *copy_task;
> > + atomic_t refcount;
>
> Hi Bruce,
>
> Is the code moving away from using atomic_t and using refcount_t
> instead. Should I be changing this as well?
Yeah, that would be a good idea, thanks.
--b.
--
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
