Merge tag 'nfsd-6.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd fixes from Chuck Lever:

 - Address a few recently-introduced issues

* tag 'nfsd-6.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  SUNRPC: Revert 5f7fc5d
  NFSD: Revert 738401a
  NFSD: Revert 6c41d9a
  nfsd: hold nfsd_mutex across entire netlink operation
  nfsd: call nfsd_last_thread() before final nfsd_put()

Author: torvalds

fs/nfsd/nfs4callback.c

@@ -84,21 +84,7 @@ static void encode_uint32(struct xdr_stream *xdr, u32 n)
 static void encode_bitmap4(struct xdr_stream *xdr, const __u32 *bitmap,
 			   size_t len)
 {
-	xdr_stream_encode_uint32_array(xdr, bitmap, len);
-}
-
-static int decode_cb_fattr4(struct xdr_stream *xdr, uint32_t *bitmap,
-				struct nfs4_cb_fattr *fattr)
-{
-	fattr->ncf_cb_change = 0;
-	fattr->ncf_cb_fsize = 0;
-	if (bitmap[0] & FATTR4_WORD0_CHANGE)
-		if (xdr_stream_decode_u64(xdr, &fattr->ncf_cb_change) < 0)
-			return -NFSERR_BAD_XDR;
-	if (bitmap[0] & FATTR4_WORD0_SIZE)
-		if (xdr_stream_decode_u64(xdr, &fattr->ncf_cb_fsize) < 0)
-			return -NFSERR_BAD_XDR;
-	return 0;
+	WARN_ON_ONCE(xdr_stream_encode_uint32_array(xdr, bitmap, len) < 0);
 }
 
 /*
@@ -371,30 +357,6 @@ encode_cb_recallany4args(struct xdr_stream *xdr,
 	hdr->nops++;
 }
 
-/*
- * CB_GETATTR4args
- *	struct CB_GETATTR4args {
- *	   nfs_fh4 fh;
- *	   bitmap4 attr_request;
- *	};
- *
- * The size and change attributes are the only one
- * guaranteed to be serviced by the client.
- */
-static void
-encode_cb_getattr4args(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr,
-			struct nfs4_cb_fattr *fattr)
-{
-	struct nfs4_delegation *dp =
-		container_of(fattr, struct nfs4_delegation, dl_cb_fattr);
-	struct knfsd_fh *fh = &dp->dl_stid.sc_file->fi_fhandle;
-
-	encode_nfs_cb_opnum4(xdr, OP_CB_GETATTR);
-	encode_nfs_fh4(xdr, fh);
-	encode_bitmap4(xdr, fattr->ncf_cb_bmap, ARRAY_SIZE(fattr->ncf_cb_bmap));
-	hdr->nops++;
-}
-
 /*
  * CB_SEQUENCE4args
  *
@@ -530,26 +492,6 @@ static void nfs4_xdr_enc_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr,
 	xdr_reserve_space(xdr, 0);
 }
 
-/*
- * 20.1.  Operation 3: CB_GETATTR - Get Attributes
- */
-static void nfs4_xdr_enc_cb_getattr(struct rpc_rqst *req,
-		struct xdr_stream *xdr, const void *data)
-{
-	const struct nfsd4_callback *cb = data;
-	struct nfs4_cb_fattr *ncf =
-		container_of(cb, struct nfs4_cb_fattr, ncf_getattr);
-	struct nfs4_cb_compound_hdr hdr = {
-		.ident = cb->cb_clp->cl_cb_ident,
-		.minorversion = cb->cb_clp->cl_minorversion,
-	};
-
-	encode_cb_compound4args(xdr, &hdr);
-	encode_cb_sequence4args(xdr, cb, &hdr);
-	encode_cb_getattr4args(xdr, &hdr, ncf);
-	encode_cb_nops(&hdr);
-}
-
 /*
  * 20.2. Operation 4: CB_RECALL - Recall a Delegation
  */
@@ -605,42 +547,6 @@ static int nfs4_xdr_dec_cb_null(struct rpc_rqst *req, struct xdr_stream *xdr,
 	return 0;
 }
 
-/*
- * 20.1.  Operation 3: CB_GETATTR - Get Attributes
- */
-static int nfs4_xdr_dec_cb_getattr(struct rpc_rqst *rqstp,
-				  struct xdr_stream *xdr,
-				  void *data)
-{
-	struct nfsd4_callback *cb = data;
-	struct nfs4_cb_compound_hdr hdr;
-	int status;
-	u32 bitmap[3] = {0};
-	u32 attrlen;
-	struct nfs4_cb_fattr *ncf =
-		container_of(cb, struct nfs4_cb_fattr, ncf_getattr);
-
-	status = decode_cb_compound4res(xdr, &hdr);
-	if (unlikely(status))
-		return status;
-
-	status = decode_cb_sequence4res(xdr, cb);
-	if (unlikely(status || cb->cb_seq_status))
-		return status;
-
-	status = decode_cb_op_status(xdr, OP_CB_GETATTR, &cb->cb_status);
-	if (status)
-		return status;
-	if (xdr_stream_decode_uint32_array(xdr, bitmap, 3) < 0)
-		return -NFSERR_BAD_XDR;
-	if (xdr_stream_decode_u32(xdr, &attrlen) < 0)
-		return -NFSERR_BAD_XDR;
-	if (attrlen > (sizeof(ncf->ncf_cb_change) + sizeof(ncf->ncf_cb_fsize)))
-		return -NFSERR_BAD_XDR;
-	status = decode_cb_fattr4(xdr, bitmap, ncf);
-	return status;
-}
-
 /*
  * 20.2. Operation 4: CB_RECALL - Recall a Delegation
  */
@@ -949,7 +855,6 @@ static const struct rpc_procinfo nfs4_cb_procedures[] = {
 	PROC(CB_NOTIFY_LOCK,	COMPOUND,	cb_notify_lock,	cb_notify_lock),
 	PROC(CB_OFFLOAD,	COMPOUND,	cb_offload,	cb_offload),
 	PROC(CB_RECALL_ANY,	COMPOUND,	cb_recall_any,	cb_recall_any),
-	PROC(CB_GETATTR,	COMPOUND,	cb_getattr,	cb_getattr),
 };
 
 static unsigned int nfs4_cb_counts[ARRAY_SIZE(nfs4_cb_procedures)];

fs/nfsd/nfs4state.c

@@ -127,7 +127,6 @@ static void free_session(struct nfsd4_session *);
 
 static const struct nfsd4_callback_ops nfsd4_cb_recall_ops;
 static const struct nfsd4_callback_ops nfsd4_cb_notify_lock_ops;
-static const struct nfsd4_callback_ops nfsd4_cb_getattr_ops;
 
 static struct workqueue_struct *laundry_wq;
 
@@ -1190,10 +1189,6 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_file *fp,
 	dp->dl_recalled = false;
 	nfsd4_init_cb(&dp->dl_recall, dp->dl_stid.sc_client,
 		      &nfsd4_cb_recall_ops, NFSPROC4_CLNT_CB_RECALL);
-	nfsd4_init_cb(&dp->dl_cb_fattr.ncf_getattr, dp->dl_stid.sc_client,
-			&nfsd4_cb_getattr_ops, NFSPROC4_CLNT_CB_GETATTR);
-	dp->dl_cb_fattr.ncf_file_modified = false;
-	dp->dl_cb_fattr.ncf_cb_bmap[0] = FATTR4_WORD0_CHANGE | FATTR4_WORD0_SIZE;
 	get_nfs4_file(fp);
 	dp->dl_stid.sc_file = fp;
 	return dp;
@@ -2901,56 +2896,11 @@ nfsd4_cb_recall_any_release(struct nfsd4_callback *cb)
 	spin_unlock(&nn->client_lock);
 }
 
-static int
-nfsd4_cb_getattr_done(struct nfsd4_callback *cb, struct rpc_task *task)
-{
-	struct nfs4_cb_fattr *ncf =
-			container_of(cb, struct nfs4_cb_fattr, ncf_getattr);
-
-	ncf->ncf_cb_status = task->tk_status;
-	switch (task->tk_status) {
-	case -NFS4ERR_DELAY:
-		rpc_delay(task, 2 * HZ);
-		return 0;
-	default:
-		return 1;
-	}
-}
-
-static void
-nfsd4_cb_getattr_release(struct nfsd4_callback *cb)
-{
-	struct nfs4_cb_fattr *ncf =
-			container_of(cb, struct nfs4_cb_fattr, ncf_getattr);
-	struct nfs4_delegation *dp =
-			container_of(ncf, struct nfs4_delegation, dl_cb_fattr);
-
-	nfs4_put_stid(&dp->dl_stid);
-	clear_bit(CB_GETATTR_BUSY, &ncf->ncf_cb_flags);
-	wake_up_bit(&ncf->ncf_cb_flags, CB_GETATTR_BUSY);
-}
-
 static const struct nfsd4_callback_ops nfsd4_cb_recall_any_ops = {
 	.done		= nfsd4_cb_recall_any_done,
 	.release	= nfsd4_cb_recall_any_release,
 };
 
-static const struct nfsd4_callback_ops nfsd4_cb_getattr_ops = {
-	.done		= nfsd4_cb_getattr_done,
-	.release	= nfsd4_cb_getattr_release,
-};
-
-void nfs4_cb_getattr(struct nfs4_cb_fattr *ncf)
-{
-	struct nfs4_delegation *dp =
-			container_of(ncf, struct nfs4_delegation, dl_cb_fattr);
-
-	if (test_and_set_bit(CB_GETATTR_BUSY, &ncf->ncf_cb_flags))
-		return;
-	refcount_inc(&dp->dl_stid.sc_count);
-	nfsd4_run_cb(&ncf->ncf_getattr);
-}
-
 static struct nfs4_client *create_client(struct xdr_netobj name,
 		struct svc_rqst *rqstp, nfs4_verifier *verf)
 {
@@ -5685,8 +5635,6 @@ nfs4_open_delegation(struct nfsd4_open *open, struct nfs4_ol_stateid *stp,
 	struct svc_fh *parent = NULL;
 	int cb_up;
 	int status = 0;
-	struct kstat stat;
-	struct path path;
 
 	cb_up = nfsd4_cb_channel_good(oo->oo_owner.so_client);
 	open->op_recall = false;
@@ -5724,18 +5672,6 @@ nfs4_open_delegation(struct nfsd4_open *open, struct nfs4_ol_stateid *stp,
 	if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE) {
 		open->op_delegate_type = NFS4_OPEN_DELEGATE_WRITE;
 		trace_nfsd_deleg_write(&dp->dl_stid.sc_stateid);
-		path.mnt = currentfh->fh_export->ex_path.mnt;
-		path.dentry = currentfh->fh_dentry;
-		if (vfs_getattr(&path, &stat,
-				(STATX_SIZE | STATX_CTIME | STATX_CHANGE_COOKIE),
-				AT_STATX_SYNC_AS_STAT)) {
-			nfs4_put_stid(&dp->dl_stid);
-			destroy_delegation(dp);
-			goto out_no_deleg;
-		}
-		dp->dl_cb_fattr.ncf_cur_fsize = stat.size;
-		dp->dl_cb_fattr.ncf_initial_cinfo =
-			nfsd4_change_attribute(&stat, d_inode(currentfh->fh_dentry));
 	} else {
 		open->op_delegate_type = NFS4_OPEN_DELEGATE_READ;
 		trace_nfsd_deleg_read(&dp->dl_stid.sc_stateid);
@@ -8492,8 +8428,6 @@ nfsd4_get_writestateid(struct nfsd4_compound_state *cstate,
  * nfsd4_deleg_getattr_conflict - Recall if GETATTR causes conflict
  * @rqstp: RPC transaction context
  * @inode: file to be checked for a conflict
- * @modified: return true if file was modified
- * @size: new size of file if modified is true
  *
  * This function is called when there is a conflict between a write
  * delegation and a change/size GETATTR from another client. The server
@@ -8502,23 +8436,21 @@ nfsd4_get_writestateid(struct nfsd4_compound_state *cstate,
  * delegation before replying to the GETATTR. See RFC 8881 section
  * 18.7.4.
  *
+ * The current implementation does not support CB_GETATTR yet. However
+ * this can avoid recalling the delegation could be added in follow up
+ * work.
+ *
  * Returns 0 if there is no conflict; otherwise an nfs_stat
  * code is returned.
  */
 __be32
-nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp, struct inode *inode,
-			     bool *modified, u64 *size)
+nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp, struct inode *inode)
 {
+	__be32 status;
 	struct file_lock_context *ctx;
-	struct nfs4_delegation *dp;
-	struct nfs4_cb_fattr *ncf;
 	struct file_lock *fl;
-	struct iattr attrs;
-	__be32 status;
-
-	might_sleep();
+	struct nfs4_delegation *dp;
 
-	*modified = false;
 	ctx = locks_inode_context(inode);
 	if (!ctx)
 		return 0;
@@ -8545,34 +8477,10 @@ nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp, struct inode *inode,
 break_lease:
 			spin_unlock(&ctx->flc_lock);
 			nfsd_stats_wdeleg_getattr_inc();
-
-			dp = fl->fl_owner;
-			ncf = &dp->dl_cb_fattr;
-			nfs4_cb_getattr(&dp->dl_cb_fattr);
-			wait_on_bit(&ncf->ncf_cb_flags, CB_GETATTR_BUSY, TASK_INTERRUPTIBLE);
-			if (ncf->ncf_cb_status) {
-				status = nfserrno(nfsd_open_break_lease(inode, NFSD_MAY_READ));
-				if (status != nfserr_jukebox ||
-						!nfsd_wait_for_delegreturn(rqstp, inode))
-					return status;
-			}
-			if (!ncf->ncf_file_modified &&
-					(ncf->ncf_initial_cinfo != ncf->ncf_cb_change ||
-					ncf->ncf_cur_fsize != ncf->ncf_cb_fsize))
-				ncf->ncf_file_modified = true;
-			if (ncf->ncf_file_modified) {
-				/*
-				 * The server would not update the file's metadata
-				 * with the client's modified size.
-				 */
-				attrs.ia_mtime = attrs.ia_ctime = current_time(inode);
-				attrs.ia_valid = ATTR_MTIME | ATTR_CTIME;
-				setattr_copy(&nop_mnt_idmap, inode, &attrs);
-				mark_inode_dirty(inode);
-				ncf->ncf_cur_fsize = ncf->ncf_cb_fsize;
-				*size = ncf->ncf_cur_fsize;
-				*modified = true;
-			}
+			status = nfserrno(nfsd_open_break_lease(inode, NFSD_MAY_READ));
+			if (status != nfserr_jukebox ||
+					!nfsd_wait_for_delegreturn(rqstp, inode))
+				return status;
 			return 0;
 		}
 		break;

fs/nfsd/nfs4xdr.c

@@ -3505,9 +3505,7 @@ nfsd4_encode_fattr4(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 		u32		attrmask[3];
 		unsigned long	mask[2];
 	} u;
-	bool file_modified;
 	unsigned long bit;
-	u64 size = 0;
 
 	WARN_ON_ONCE(bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1);
 	WARN_ON_ONCE(!nfsd_attrs_supported(minorversion, bmval));
@@ -3534,8 +3532,7 @@ nfsd4_encode_fattr4(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 	}
 	args.size = 0;
 	if (u.attrmask[0] & (FATTR4_WORD0_CHANGE | FATTR4_WORD0_SIZE)) {
-		status = nfsd4_deleg_getattr_conflict(rqstp, d_inode(dentry),
-						      &file_modified, &size);
+		status = nfsd4_deleg_getattr_conflict(rqstp, d_inode(dentry));
 		if (status)
 			goto out;
 	}
@@ -3545,7 +3542,7 @@ nfsd4_encode_fattr4(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 			  AT_STATX_SYNC_AS_STAT);
 	if (err)
 		goto out_nfserr;
-	args.size = file_modified ? size : args.stat.size;
+	args.size = args.stat.size;
 
 	if (!(args.stat.result_mask & STATX_BTIME))
 		/* underlying FS does not offer btime so we can't share it */

fs/nfsd/nfsctl.c

@@ -705,8 +705,10 @@ static ssize_t __write_ports_addfd(char *buf, struct net *net, const struct cred
 
 	err = svc_addsock(nn->nfsd_serv, net, fd, buf, SIMPLE_TRANSACTION_LIMIT, cred);
 
-	if (err >= 0 &&
-	    !nn->nfsd_serv->sv_nrthreads && !xchg(&nn->keep_active, 1))
+	if (err < 0 && !nn->nfsd_serv->sv_nrthreads && !nn->keep_active)
+		nfsd_last_thread(net);
+	else if (err >= 0 &&
+		 !nn->nfsd_serv->sv_nrthreads && !xchg(&nn->keep_active, 1))
 		svc_get(nn->nfsd_serv);
 
 	nfsd_put(net);
@@ -757,6 +759,9 @@ static ssize_t __write_ports_addxprt(char *buf, struct net *net, const struct cr
 		svc_xprt_put(xprt);
 	}
 out_err:
+	if (!nn->nfsd_serv->sv_nrthreads && !nn->keep_active)
+		nfsd_last_thread(net);
+
 	nfsd_put(net);
 	return err;
 }
@@ -1510,11 +1515,10 @@ int nfsd_nl_rpc_status_get_start(struct netlink_callback *cb)
 	int ret = -ENODEV;
 
 	mutex_lock(&nfsd_mutex);
-	if (nn->nfsd_serv) {
-		svc_get(nn->nfsd_serv);
+	if (nn->nfsd_serv)
 		ret = 0;
-	}
-	mutex_unlock(&nfsd_mutex);
+	else
+		mutex_unlock(&nfsd_mutex);
 
 	return ret;
 }
@@ -1686,8 +1690,6 @@ int nfsd_nl_rpc_status_get_dumpit(struct sk_buff *skb,
  */
 int nfsd_nl_rpc_status_get_done(struct netlink_callback *cb)
 {
-	mutex_lock(&nfsd_mutex);
-	nfsd_put(sock_net(cb->skb->sk));
 	mutex_unlock(&nfsd_mutex);
 
 	return 0;

fs/nfsd/nfsd.h

@@ -155,6 +155,7 @@ int nfsd_vers(struct nfsd_net *nn, int vers, enum vers_op change);
 int nfsd_minorversion(struct nfsd_net *nn, u32 minorversion, enum vers_op change);
 void nfsd_reset_versions(struct nfsd_net *nn);
 int nfsd_create_serv(struct net *net);
+void nfsd_last_thread(struct net *net);
 
 extern int nfsd_max_blksize;