Commit aa0ebd21 authored by Chuck Lever's avatar Chuck Lever
Browse files

NFSD: Add nfsd4_copy time-to-live 



Keep async copy state alive for a few lease cycles after the copy
completes so that OFFLOAD_STATUS returns something meaningful.

This means that NFSD's client shutdown processing needs to purge
any of this state that happens to be waiting to die.

Reviewed-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent ac0514f4

fs/nfsd/nfs4proc.c

+5 −2
Original line number Diff line number Diff line
@@ -1326,10 +1326,12 @@ void nfsd4_async_copy_reaper(struct nfsd_net *nn) 
		list_for_each_safe(pos, next, &clp->async_copies) {

			copy = list_entry(pos, struct nfsd4_copy, copies);

			if (test_bit(NFSD4_COPY_F_OFFLOAD_DONE, &copy->cp_flags)) {

				if (--copy->cp_ttl) {

					list_del_init(&copy->copies);

					list_add(&copy->copies, &reaplist);

				}

			}

		}

		spin_unlock(&clp->async_lock);

	}

	spin_unlock(&nn->client_lock);
@@ -1921,6 +1923,7 @@ nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, 
		async_copy->cp_nn = nn;

		INIT_LIST_HEAD(&async_copy->copies);

		refcount_set(&async_copy->refcount, 1);

		async_copy->cp_ttl = NFSD_COPY_INITIAL_TTL;

		/* Arbitrary cap on number of pending async copy operations */

		if (atomic_inc_return(&nn->pending_async_copies) >

				(int)rqstp->rq_pool->sp_nrthreads)

fs/nfsd/state.h

+15 −0
Original line number Diff line number Diff line
@@ -137,6 +137,21 @@ struct nfs4_cpntf_state { 
	time64_t		cpntf_time;	/* last time stateid used */

};



/*

 * RFC 7862 Section 4.8 states:

 *

 * | A copy offload stateid will be valid until either (A) the client

 * | or server restarts or (B) the client returns the resource by

 * | issuing an OFFLOAD_CANCEL operation or the client replies to a

 * | CB_OFFLOAD operation.

 *

 * Because a client might not reply to a CB_OFFLOAD, or a reply

 * might get lost due to connection loss, NFSD purges async copy

 * state after a short period to prevent it from accumulating

 * over time.

 */

#define NFSD_COPY_INITIAL_TTL 10



struct nfs4_cb_fattr {

	struct nfsd4_callback ncf_getattr;

	u32 ncf_cb_status;

fs/nfsd/xdr4.h

+1 −0
Original line number Diff line number Diff line
@@ -715,6 +715,7 @@ struct nfsd4_copy { 
	struct list_head	copies;

	struct task_struct	*copy_task;

	refcount_t		refcount;

	unsigned int		cp_ttl;



	struct nfsd4_ssc_umount_item *ss_nsui;

	struct nfs_fh		c_fh;