NFS: skip recovery of copy open on dest server

Mark the open created for the source file on the destination
server. Then if this open is going thru a recovery, then fail
the recovery as we don't need to be recoving a "fake" open.
We need to fail the ongoing READs and vfs_copy_file_range().
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

fs/nfs/nfs4_fs.h

@@ -168,6 +168,7 @@ enum {
 	NFS_STATE_CHANGE_WAIT,		/* A state changing operation is outstanding */
 #ifdef CONFIG_NFS_V4_2
 	NFS_CLNT_DST_SSC_COPY_STATE,    /* dst server open state on client*/
+	NFS_SRV_SSC_COPY_STATE,		/* ssc state on the dst server */
 #endif /* CONFIG_NFS_V4_2 */
 };
 

fs/nfs/nfs4file.c

@@ -352,6 +352,7 @@ nfs42_ssc_open(struct vfsmount *ss_mnt, struct nfs_fh *src_fh,
 	if (ctx->state == NULL)
 		goto out_stateowner;
 
+	set_bit(NFS_SRV_SSC_COPY_STATE, &ctx->state->flags);
 	set_bit(NFS_OPEN_STATE, &ctx->state->flags);
 	memcpy(&ctx->state->open_stateid.other, &stateid->other,
 	       NFS4_STATEID_OTHER_SIZE);

fs/nfs/nfs4state.c

@@ -1609,6 +1609,9 @@ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs
 	struct nfs4_state *state;
 	unsigned int loop = 0;
 	int status = 0;
+#ifdef CONFIG_NFS_V4_2
+	bool found_ssc_copy_state = false;
+#endif /* CONFIG_NFS_V4_2 */
 
 	/* Note: we rely on the sp->so_states list being ordered 
 	 * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
@@ -1628,6 +1631,13 @@ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs
 			continue;
 		if (state->state == 0)
 			continue;
+#ifdef CONFIG_NFS_V4_2
+		if (test_bit(NFS_SRV_SSC_COPY_STATE, &state->flags)) {
+			nfs4_state_mark_recovery_failed(state, -EIO);
+			found_ssc_copy_state = true;
+			continue;
+		}
+#endif /* CONFIG_NFS_V4_2 */
 		refcount_inc(&state->count);
 		spin_unlock(&sp->so_lock);
 		status = __nfs4_reclaim_open_state(sp, state, ops);
@@ -1682,6 +1692,10 @@ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs
 	}
 	raw_write_seqcount_end(&sp->so_reclaim_seqcount);
 	spin_unlock(&sp->so_lock);
+#ifdef CONFIG_NFS_V4_2
+	if (found_ssc_copy_state)
+		return -EIO;
+#endif /* CONFIG_NFS_V4_2 */
 	return 0;
 out_err:
 	nfs4_put_open_state(state);