Merge tag 'nfsd-4.12' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Another RDMA update from Chuck Lever, and a bunch of miscellaneous
  bugfixes"

* tag 'nfsd-4.12' of git://linux-nfs.org/~bfields/linux: (26 commits)
  nfsd: Fix up the "supattr_exclcreat" attributes
  nfsd: encoders mustn't use unitialized values in error cases
  nfsd: fix undefined behavior in nfsd4_layout_verify
  lockd: fix lockd shutdown race
  NFSv4: Fix callback server shutdown
  SUNRPC: Refactor svc_set_num_threads()
  NFSv4.x/callback: Create the callback service through svc_create_pooled
  lockd: remove redundant check on block
  svcrdma: Clean out old XDR encoders
  svcrdma: Remove the req_map cache
  svcrdma: Remove unused RDMA Write completion handler
  svcrdma: Reduce size of sge array in struct svc_rdma_op_ctxt
  svcrdma: Clean up RPC-over-RDMA backchannel reply processing
  svcrdma: Report Write/Reply chunk overruns
  svcrdma: Clean up RDMA_ERROR path
  svcrdma: Use rdma_rw API in RPC reply path
  svcrdma: Introduce local rdma_rw API helpers
  svcrdma: Clean up svc_rdma_get_inv_rkey()
  svcrdma: Add helper to save pages under I/O
  svcrdma: Eliminate RPCRDMA_SQ_DEPTH_MULT
  ...
nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
		   const char *name, unsigned int len,
		   struct svc_export **exp_ret, struct dentry **dentry_ret)
{
	struct svc_export	*exp;
	struct dentry		*dparent;
	struct dentry		*dentry;
	int			host_err;

	dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);

	dparent = fhp->fh_dentry;
	exp = exp_get(fhp->fh_export);

	/* Lookup the name, but don't follow links */
	if (isdotent(name, len)) {
		if (len==1)
			dentry = dget(dparent);
		else if (dparent != exp->ex_path.dentry)
			dentry = dget_parent(dparent);
		else if (!EX_NOHIDE(exp) && !nfsd_v4client(rqstp))
			dentry = dget(dparent); /* .. == . just like at / */
		else {
			/* checking mountpoint crossing is very different when stepping up */
			host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry);
			if (host_err)
				goto out_nfserr;
		}
	} else {
		/*
		 * In the nfsd4_open() case, this may be held across
		 * subsequent open and delegation acquisition which may
		 * need to take the child's i_mutex:
		 */
		fh_lock_nested(fhp, I_MUTEX_PARENT);
		dentry = lookup_one_len(name, dparent, len);
		host_err = PTR_ERR(dentry);
		if (IS_ERR(dentry))
			goto out_nfserr;
		if (nfsd_mountpoint(dentry, exp)) {
			/*
			 * We don't need the i_mutex after all.  It's
			 * still possible we could open this (regular
			 * files can be mountpoints too), but the
			 * i_mutex is just there to prevent renames of
			 * something that we might be about to delegate,
			 * and a mountpoint won't be renamed:
			 */
			fh_unlock(fhp);
			if ((host_err = nfsd_cross_mnt(rqstp, &dentry, &exp))) {
				dput(dentry);
				goto out_nfserr;
			}
		}
	}
	*dentry_ret = dentry;
	*exp_ret = exp;
	return 0;

out_nfserr:
	exp_put(exp);
	return nfserrno(host_err);
}

nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
		   const char *name, unsigned int len,
		   struct svc_export **exp_ret, struct dentry **dentry_ret)
{
	struct svc_export	*exp;
	struct dentry		*dparent;
	struct dentry		*dentry;
	int			host_err;

	dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);

	dparent = fhp->fh_dentry;
	exp = exp_get(fhp->fh_export);

	/* Lookup the name, but don't follow links */
	if (isdotent(name, len)) {
		if (len==1)
			dentry = dget(dparent);
		else if (dparent != exp->ex_path.dentry)
			dentry = dget_parent(dparent);
		else if (!EX_NOHIDE(exp) && !nfsd_v4client(rqstp))
			dentry = dget(dparent); /* .. == . just like at / */
		else {
			/* checking mountpoint crossing is very different when stepping up */
			host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry);
			if (host_err)
				goto out_nfserr;
		}
	} else {
		/*
		 * In the nfsd4_open() case, this may be held across
		 * subsequent open and delegation acquisition which may
		 * need to take the child's i_mutex:
		 */
		fh_lock_nested(fhp, I_MUTEX_PARENT);
		dentry = lookup_one_len(name, dparent, len);
		host_err = PTR_ERR(dentry);
		if (IS_ERR(dentry))
			goto out_nfserr;
		if (nfsd_mountpoint(dentry, exp)) {
			/*
			 * We don't need the i_mutex after all.  It's
			 * still possible we could open this (regular
			 * files can be mountpoints too), but the
			 * i_mutex is just there to prevent renames of
			 * something that we might be about to delegate,
			 * and a mountpoint won't be renamed:
			 */
			fh_unlock(fhp);
			if ((host_err = nfsd_cross_mnt(rqstp, &dentry, &exp))) {
				dput(dentry);
				goto out_nfserr;
			}
		}
	}
	*dentry_ret = dentry;
	*exp_ret = exp;
	return 0;

out_nfserr:
	exp_put(exp);
	return nfserrno(host_err);
}
