Merge tag 'nfs-for-3.20-2' of git://git.linux-nfs.org/projects/trondm…

…y/linux-nfs

Pull more NFS client updates from Trond Myklebust:
 "Highlights include:

   - Fix a use-after-free in decode_cb_sequence_args()
   - Fix a compile error when #undef CONFIG_PROC_FS
   - NFSv4.1 backchannel spinlocking issue
   - Cleanups in the NFS unstable write code requested by Linus
   - NFSv4.1 fix issues when the server denies our backchannel request
   - Cleanups in create_session and bind_conn_to_session"

* tag 'nfs-for-3.20-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFSv4.1: Clean up bind_conn_to_session
  NFSv4.1: Always set up a forward channel when binding the session
  NFSv4.1: Don't set up a backchannel if the server didn't agree to do so
  NFSv4.1: Clean up create_session
  pnfs: Refactor the *_layout_mark_request_commit to use pnfs_layout_mark_request_commit
  NFSv4: Kill unused nfs_inode->delegation_state field
  NFS: struct nfs_commit_info.lock must always point to inode->i_lock
  nfs: Can call nfs_clear_page_commit() instead
  nfs: Provide and use helper functions for marking a page as unstable
  SUNRPC: Always manipulate rpc_rqst::rq_bc_pa_list under xprt->bc_pa_lock
  SUNRPC: Fix a compile error when #undef CONFIG_PROC_FS
  NFSv4.1: Convert open-coded array allocation calls to kmalloc_array()
  NFSv4.1: Fix a kfree() of uninitialised pointers in decode_cb_sequence_args

fs/nfs/callback_proc.c

@@ -427,6 +427,8 @@ __be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
 	if (clp == NULL)
 		goto out;
 
+	if (!(clp->cl_session->flags & SESSION4_BACK_CHAN))
+		goto out;
 	tbl = &clp->cl_session->bc_slot_table;
 
 	spin_lock(&tbl->slot_tbl_lock);

fs/nfs/callback_xdr.c

@@ -313,7 +313,7 @@ __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 		goto out;
 	}
 
-	args->devs = kmalloc(n * sizeof(*args->devs), GFP_KERNEL);
+	args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
 	if (!args->devs) {
 		status = htonl(NFS4ERR_DELAY);
 		goto out;
@@ -415,7 +415,7 @@ static __be32 decode_rc_list(struct xdr_stream *xdr,
 			     rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
 		if (unlikely(p == NULL))
 			goto out;
-		rc_list->rcl_refcalls = kmalloc(rc_list->rcl_nrefcalls *
+		rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
 						sizeof(*rc_list->rcl_refcalls),
 						GFP_KERNEL);
 		if (unlikely(rc_list->rcl_refcalls == NULL))
@@ -464,8 +464,10 @@ static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
 
 		for (i = 0; i < args->csa_nrclists; i++) {
 			status = decode_rc_list(xdr, &args->csa_rclists[i]);
-			if (status)
+			if (status) {
+				args->csa_nrclists = i;
 				goto out_free;
+			}
 		}
 	}
 	status = 0;

fs/nfs/delegation.c

@@ -180,7 +180,6 @@ void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred,
 			delegation->cred = get_rpccred(cred);
 			clear_bit(NFS_DELEGATION_NEED_RECLAIM,
 				  &delegation->flags);
-			NFS_I(inode)->delegation_state = delegation->type;
 			spin_unlock(&delegation->lock);
 			put_rpccred(oldcred);
 			rcu_read_unlock();
@@ -275,7 +274,6 @@ nfs_detach_delegation_locked(struct nfs_inode *nfsi,
 	set_bit(NFS_DELEGATION_RETURNING, &delegation->flags);
 	list_del_rcu(&delegation->super_list);
 	delegation->inode = NULL;
-	nfsi->delegation_state = 0;
 	rcu_assign_pointer(nfsi->delegation, NULL);
 	spin_unlock(&delegation->lock);
 	return delegation;
@@ -355,7 +353,6 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
 					&delegation->stateid)) {
 			nfs_update_inplace_delegation(old_delegation,
 					delegation);
-			nfsi->delegation_state = old_delegation->type;
 			goto out;
 		}
 		/*
@@ -379,7 +376,6 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
 			goto out;
 	}
 	list_add_rcu(&delegation->super_list, &server->delegations);
-	nfsi->delegation_state = delegation->type;
 	rcu_assign_pointer(nfsi->delegation, delegation);
 	delegation = NULL;
 

fs/nfs/direct.c

@@ -283,7 +283,7 @@ static void nfs_direct_release_pages(struct page **pages, unsigned int npages)
 void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
 			      struct nfs_direct_req *dreq)
 {
-	cinfo->lock = &dreq->lock;
+	cinfo->lock = &dreq->inode->i_lock;
 	cinfo->mds = &dreq->mds_cinfo;
 	cinfo->ds = &dreq->ds_cinfo;
 	cinfo->dreq = dreq;

fs/nfs/filelayout/filelayout.c

@@ -960,52 +960,19 @@ filelayout_mark_request_commit(struct nfs_page *req,
 {
 	struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 	u32 i, j;
-	struct list_head *list;
-	struct pnfs_commit_bucket *buckets;
 
 	if (fl->commit_through_mds) {
-		list = &cinfo->mds->list;
-		spin_lock(cinfo->lock);
-		goto mds_commit;
-	}
-
-	/* Note that we are calling nfs4_fl_calc_j_index on each page
-	 * that ends up being committed to a data server.  An attractive
-	 * alternative is to add a field to nfs_write_data and nfs_page
-	 * to store the value calculated in filelayout_write_pagelist
-	 * and just use that here.
-	 */
-	j = nfs4_fl_calc_j_index(lseg, req_offset(req));
-	i = select_bucket_index(fl, j);
-	spin_lock(cinfo->lock);
-	buckets = cinfo->ds->buckets;
-	list = &buckets[i].written;
-	if (list_empty(list)) {
-		/* Non-empty buckets hold a reference on the lseg.  That ref
-		 * is normally transferred to the COMMIT call and released
-		 * there.  It could also be released if the last req is pulled
-		 * off due to a rewrite, in which case it will be done in
-		 * pnfs_generic_clear_request_commit
+		nfs_request_add_commit_list(req, &cinfo->mds->list, cinfo);
+	} else {
+		/* Note that we are calling nfs4_fl_calc_j_index on each page
+		 * that ends up being committed to a data server.  An attractive
+		 * alternative is to add a field to nfs_write_data and nfs_page
+		 * to store the value calculated in filelayout_write_pagelist
+		 * and just use that here.
 		 */
-		buckets[i].wlseg = pnfs_get_lseg(lseg);
-	}
-	set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
-	cinfo->ds->nwritten++;
-
-mds_commit:
-	/* nfs_request_add_commit_list(). We need to add req to list without
-	 * dropping cinfo lock.
-	 */
-	set_bit(PG_CLEAN, &(req)->wb_flags);
-	nfs_list_add_request(req, list);
-	cinfo->mds->ncommit++;
-	spin_unlock(cinfo->lock);
-	if (!cinfo->dreq) {
-		inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
-		inc_bdi_stat(inode_to_bdi(page_file_mapping(req->wb_page)->host),
-			     BDI_RECLAIMABLE);
-		__mark_inode_dirty(req->wb_context->dentry->d_inode,
-				   I_DIRTY_DATASYNC);
+		j = nfs4_fl_calc_j_index(lseg, req_offset(req));
+		i = select_bucket_index(fl, j);
+		pnfs_layout_mark_request_commit(req, lseg, cinfo, i);
 	}
 }
 

fs/nfs/flexfilelayout/flexfilelayout.c

@@ -1332,47 +1332,6 @@ ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 	return PNFS_ATTEMPTED;
 }
 
-static void
-ff_layout_mark_request_commit(struct nfs_page *req,
-			      struct pnfs_layout_segment *lseg,
-			      struct nfs_commit_info *cinfo,
-			      u32 ds_commit_idx)
-{
-	struct list_head *list;
-	struct pnfs_commit_bucket *buckets;
-
-	spin_lock(cinfo->lock);
-	buckets = cinfo->ds->buckets;
-	list = &buckets[ds_commit_idx].written;
-	if (list_empty(list)) {
-		/* Non-empty buckets hold a reference on the lseg.  That ref
-		 * is normally transferred to the COMMIT call and released
-		 * there.  It could also be released if the last req is pulled
-		 * off due to a rewrite, in which case it will be done in
-		 * pnfs_common_clear_request_commit
-		 */
-		WARN_ON_ONCE(buckets[ds_commit_idx].wlseg != NULL);
-		buckets[ds_commit_idx].wlseg = pnfs_get_lseg(lseg);
-	}
-	set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
-	cinfo->ds->nwritten++;
-
-	/* nfs_request_add_commit_list(). We need to add req to list without
-	 * dropping cinfo lock.
-	 */
-	set_bit(PG_CLEAN, &(req)->wb_flags);
-	nfs_list_add_request(req, list);
-	cinfo->mds->ncommit++;
-	spin_unlock(cinfo->lock);
-	if (!cinfo->dreq) {
-		inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
-		inc_bdi_stat(inode_to_bdi(page_file_mapping(req->wb_page)->host),
-			     BDI_RECLAIMABLE);
-		__mark_inode_dirty(req->wb_context->dentry->d_inode,
-				   I_DIRTY_DATASYNC);
-	}
-}
-
 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
 {
 	return i;
@@ -1540,7 +1499,7 @@ static struct pnfs_layoutdriver_type flexfilelayout_type = {
 	.pg_write_ops		= &ff_layout_pg_write_ops,
 	.get_ds_info		= ff_layout_get_ds_info,
 	.free_deviceid_node	= ff_layout_free_deveiceid_node,
-	.mark_request_commit	= ff_layout_mark_request_commit,
+	.mark_request_commit	= pnfs_layout_mark_request_commit,
 	.clear_request_commit	= pnfs_generic_clear_request_commit,
 	.scan_commit_lists	= pnfs_generic_scan_commit_lists,
 	.recover_commit_reqs	= pnfs_generic_recover_commit_reqs,

fs/nfs/inode.c

@@ -1775,7 +1775,6 @@ static inline void nfs4_init_once(struct nfs_inode *nfsi)
 #if IS_ENABLED(CONFIG_NFS_V4)
 	INIT_LIST_HEAD(&nfsi->open_states);
 	nfsi->delegation = NULL;
-	nfsi->delegation_state = 0;
 	init_rwsem(&nfsi->rwsem);
 	nfsi->layout = NULL;
 #endif

fs/nfs/internal.h

@@ -597,6 +597,19 @@ void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
 		sb->s_maxbytes = MAX_LFS_FILESIZE;
 }
 
+/*
+ * Record the page as unstable and mark its inode as dirty.
+ */
+static inline
+void nfs_mark_page_unstable(struct page *page)
+{
+	struct inode *inode = page_file_mapping(page)->host;
+
+	inc_zone_page_state(page, NR_UNSTABLE_NFS);
+	inc_bdi_stat(inode_to_bdi(inode), BDI_RECLAIMABLE);
+	 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
+}
+
 /*
  * Determine the number of bytes of data the page contains
  */

fs/nfs/nfs4proc.c

@@ -6648,47 +6648,47 @@ nfs41_same_server_scope(struct nfs41_server_scope *a,
 int nfs4_proc_bind_conn_to_session(struct nfs_client *clp, struct rpc_cred *cred)
 {
 	int status;
+	struct nfs41_bind_conn_to_session_args args = {
+		.client = clp,
+		.dir = NFS4_CDFC4_FORE_OR_BOTH,
+	};
 	struct nfs41_bind_conn_to_session_res res;
 	struct rpc_message msg = {
 		.rpc_proc =
 			&nfs4_procedures[NFSPROC4_CLNT_BIND_CONN_TO_SESSION],
-		.rpc_argp = clp,
+		.rpc_argp = &args,
 		.rpc_resp = &res,
 		.rpc_cred = cred,
 	};
 
 	dprintk("--> %s\n", __func__);
 
-	res.session = kzalloc(sizeof(struct nfs4_session), GFP_NOFS);
-	if (unlikely(res.session == NULL)) {
-		status = -ENOMEM;
-		goto out;
-	}
+	nfs4_copy_sessionid(&args.sessionid, &clp->cl_session->sess_id);
+	if (!(clp->cl_session->flags & SESSION4_BACK_CHAN))
+		args.dir = NFS4_CDFC4_FORE;
 
 	status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
 	trace_nfs4_bind_conn_to_session(clp, status);
 	if (status == 0) {
-		if (memcmp(res.session->sess_id.data,
+		if (memcmp(res.sessionid.data,
 		    clp->cl_session->sess_id.data, NFS4_MAX_SESSIONID_LEN)) {
 			dprintk("NFS: %s: Session ID mismatch\n", __func__);
 			status = -EIO;
-			goto out_session;
+			goto out;
 		}
-		if (res.dir != NFS4_CDFS4_BOTH) {
+		if ((res.dir & args.dir) != res.dir || res.dir == 0) {
 			dprintk("NFS: %s: Unexpected direction from server\n",
 				__func__);
 			status = -EIO;
-			goto out_session;
+			goto out;
 		}
-		if (res.use_conn_in_rdma_mode) {
+		if (res.use_conn_in_rdma_mode != args.use_conn_in_rdma_mode) {
 			dprintk("NFS: %s: Server returned RDMA mode = true\n",
 				__func__);
 			status = -EIO;
-			goto out_session;
+			goto out;
 		}
 	}
-out_session:
-	kfree(res.session);
 out:
 	dprintk("<-- %s status= %d\n", __func__, status);
 	return status;
@@ -7166,10 +7166,11 @@ static void nfs4_init_channel_attrs(struct nfs41_create_session_args *args)
 		args->bc_attrs.max_reqs);
 }
 
-static int nfs4_verify_fore_channel_attrs(struct nfs41_create_session_args *args, struct nfs4_session *session)
+static int nfs4_verify_fore_channel_attrs(struct nfs41_create_session_args *args,
+		struct nfs41_create_session_res *res)
 {
 	struct nfs4_channel_attrs *sent = &args->fc_attrs;
-	struct nfs4_channel_attrs *rcvd = &session->fc_attrs;
+	struct nfs4_channel_attrs *rcvd = &res->fc_attrs;
 
 	if (rcvd->max_resp_sz > sent->max_resp_sz)
 		return -EINVAL;
@@ -7188,11 +7189,14 @@ static int nfs4_verify_fore_channel_attrs(struct nfs41_create_session_args *args
 	return 0;
 }
 
-static int nfs4_verify_back_channel_attrs(struct nfs41_create_session_args *args, struct nfs4_session *session)
+static int nfs4_verify_back_channel_attrs(struct nfs41_create_session_args *args,
+		struct nfs41_create_session_res *res)
 {
 	struct nfs4_channel_attrs *sent = &args->bc_attrs;
-	struct nfs4_channel_attrs *rcvd = &session->bc_attrs;
+	struct nfs4_channel_attrs *rcvd = &res->bc_attrs;
 
+	if (!(res->flags & SESSION4_BACK_CHAN))
+		goto out;
 	if (rcvd->max_rqst_sz > sent->max_rqst_sz)
 		return -EINVAL;
 	if (rcvd->max_resp_sz < sent->max_resp_sz)
@@ -7204,18 +7208,30 @@ static int nfs4_verify_back_channel_attrs(struct nfs41_create_session_args *args
 		return -EINVAL;
 	if (rcvd->max_reqs != sent->max_reqs)
 		return -EINVAL;
+out:
 	return 0;
 }
 
 static int nfs4_verify_channel_attrs(struct nfs41_create_session_args *args,
-				     struct nfs4_session *session)
+				     struct nfs41_create_session_res *res)
 {
 	int ret;
 
-	ret = nfs4_verify_fore_channel_attrs(args, session);
+	ret = nfs4_verify_fore_channel_attrs(args, res);
 	if (ret)
 		return ret;
-	return nfs4_verify_back_channel_attrs(args, session);
+	return nfs4_verify_back_channel_attrs(args, res);
+}
+
+static void nfs4_update_session(struct nfs4_session *session,
+		struct nfs41_create_session_res *res)
+{
+	nfs4_copy_sessionid(&session->sess_id, &res->sessionid);
+	session->flags = res->flags;
+	memcpy(&session->fc_attrs, &res->fc_attrs, sizeof(session->fc_attrs));
+	if (res->flags & SESSION4_BACK_CHAN)
+		memcpy(&session->bc_attrs, &res->bc_attrs,
+				sizeof(session->bc_attrs));
 }
 
 static int _nfs4_proc_create_session(struct nfs_client *clp,
@@ -7224,11 +7240,12 @@ static int _nfs4_proc_create_session(struct nfs_client *clp,
 	struct nfs4_session *session = clp->cl_session;
 	struct nfs41_create_session_args args = {
 		.client = clp,
+		.clientid = clp->cl_clientid,
+		.seqid = clp->cl_seqid,
 		.cb_program = NFS4_CALLBACK,
 	};
-	struct nfs41_create_session_res res = {
-		.client = clp,
-	};
+	struct nfs41_create_session_res res;
+
 	struct rpc_message msg = {
 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CREATE_SESSION],
 		.rpc_argp = &args,
@@ -7245,11 +7262,15 @@ static int _nfs4_proc_create_session(struct nfs_client *clp,
 
 	if (!status) {
 		/* Verify the session's negotiated channel_attrs values */
-		status = nfs4_verify_channel_attrs(&args, session);
+		status = nfs4_verify_channel_attrs(&args, &res);
 		/* Increment the clientid slot sequence id */
-		clp->cl_seqid++;
+		if (clp->cl_seqid == res.seqid)
+			clp->cl_seqid++;
+		if (status)
+			goto out;
+		nfs4_update_session(session, &res);
 	}
-
+out:
 	return status;
 }
 

fs/nfs/nfs4session.c

@@ -450,7 +450,7 @@ int nfs4_setup_session_slot_tables(struct nfs4_session *ses)
 	tbl = &ses->fc_slot_table;
 	tbl->session = ses;
 	status = nfs4_realloc_slot_table(tbl, ses->fc_attrs.max_reqs, 1);
-	if (status) /* -ENOMEM */
+	if (status || !(ses->flags & SESSION4_BACK_CHAN)) /* -ENOMEM */
 		return status;
 	/* Back channel */
 	tbl = &ses->bc_slot_table;