Merge tag 'nfsd-4.19-1' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Chuck Lever fixed a problem with NFSv4.0 callbacks over GSS from
  multi-homed servers.

  The only new feature is a minor bit of protocol (change_attr_type)
  which the client doesn't even use yet.

  Other than that, various bugfixes and cleanup"

* tag 'nfsd-4.19-1' of git://linux-nfs.org/~bfields/linux: (27 commits)
  sunrpc: Add comment defining gssd upcall API keywords
  nfsd: Remove callback_cred
  nfsd: Use correct credential for NFSv4.0 callback with GSS
  sunrpc: Extract target name into svc_cred
  sunrpc: Enable the kernel to specify the hostname part of service principals
  sunrpc: Don't use stack buffer with scatterlist
  rpc: remove unneeded variable 'ret' in rdma_listen_handler
  nfsd: use true and false for boolean values
  nfsd: constify write_op[]
  fs/nfsd: Delete invalid assignment statements in nfsd4_decode_exchange_id
  NFSD: Handle full-length symlinks
  NFSD: Refactor the generic write vector fill helper
  svcrdma: Clean up Read chunk path
  svcrdma: Avoid releasing a page in svc_xprt_release()
  nfsd: Mark expected switch fall-through
  sunrpc: remove redundant variables 'checksumlen','blocksize' and 'data'
  nfsd: fix leaked file lock with nfs exported overlayfs
  nfsd: don't advertise a SCSI layout for an unsupported request_queue
  nfsd: fix corrupted reply to badly ordered compound
  nfsd: clarify check_op_ordering
  ...

5 files changed, 23 insertions, 27 deletions

diff --git a/net/sunrpc/xprtrdma/svc_rdma.c b/net/sunrpc/xprtrdma/svc_rdma.c
index 357ba90c382d..134bef6a451e 100644
--- a/net/sunrpc/xprtrdma/svc_rdma.c
+++ b/net/sunrpc/xprtrdma/svc_rdma.c
@@ -94,7 +94,6 @@ static int read_reset_stat(struct ctl_table *table, int write,
 		atomic_set(stat, 0);
 	else {
 		char str_buf[32];
-		char *data;
 		int len = snprintf(str_buf, 32, "%d\n", atomic_read(stat));
 		if (len >= 32)
 			return -EFAULT;
@@ -103,7 +102,6 @@ static int read_reset_stat(struct ctl_table *table, int write,
 			*lenp = 0;
 			return 0;
 		}
-		data = &str_buf[*ppos];
 		len -= *ppos;
 		if (len > *lenp)
 			len = *lenp;
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
index 2ef75e885411..b24d5b8f2fee 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
@@ -365,9 +365,6 @@ static void svc_rdma_build_arg_xdr(struct svc_rqst *rqstp,
 	arg->page_base = 0;
 	arg->buflen = ctxt->rc_byte_len;
 	arg->len = ctxt->rc_byte_len;
-
-	rqstp->rq_respages = &rqstp->rq_pages[0];
-	rqstp->rq_next_page = rqstp->rq_respages + 1;
 }
 
 /* This accommodates the largest possible Write chunk,
@@ -729,6 +726,12 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
 
 	svc_rdma_build_arg_xdr(rqstp, ctxt);
 
+	/* Prevent svc_xprt_release from releasing pages in rq_pages
+	 * if we return 0 or an error.
+	 */
+	rqstp->rq_respages = rqstp->rq_pages;
+	rqstp->rq_next_page = rqstp->rq_respages;
+
 	p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
 	ret = svc_rdma_xdr_decode_req(&rqstp->rq_arg);
 	if (ret < 0)
diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c
index 04cb3363172a..dc1951759a8e 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_rw.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c
@@ -680,6 +680,7 @@ static int svc_rdma_build_read_chunk(struct svc_rqst *rqstp,
 				     struct svc_rdma_read_info *info,
 				     __be32 *p)
 {
+	unsigned int i;
 	int ret;
 
 	ret = -EINVAL;
@@ -702,6 +703,12 @@ static int svc_rdma_build_read_chunk(struct svc_rqst *rqstp,
 		info->ri_chunklen += rs_length;
 	}
 
+	/* Pages under I/O have been copied to head->rc_pages.
+	 * Prevent their premature release by svc_xprt_release() .
+	 */
+	for (i = 0; i < info->ri_readctxt->rc_page_count; i++)
+		rqstp->rq_pages[i] = NULL;
+
 	return ret;
 }
 
@@ -817,7 +824,6 @@ int svc_rdma_recv_read_chunk(struct svcxprt_rdma *rdma, struct svc_rqst *rqstp,
 			     struct svc_rdma_recv_ctxt *head, __be32 *p)
 {
 	struct svc_rdma_read_info *info;
-	struct page **page;
 	int ret;
 
 	/* The request (with page list) is constructed in
@@ -844,27 +850,15 @@ int svc_rdma_recv_read_chunk(struct svcxprt_rdma *rdma, struct svc_rqst *rqstp,
 		ret = svc_rdma_build_normal_read_chunk(rqstp, info, p);
 	else
 		ret = svc_rdma_build_pz_read_chunk(rqstp, info, p);
-
-	/* Mark the start of the pages that can be used for the reply */
-	if (info->ri_pageoff > 0)
-		info->ri_pageno++;
-	rqstp->rq_respages = &rqstp->rq_pages[info->ri_pageno];
-	rqstp->rq_next_page = rqstp->rq_respages + 1;
-
 	if (ret < 0)
-		goto out;
+		goto out_err;
 
 	ret = svc_rdma_post_chunk_ctxt(&info->ri_cc);
-
-out:
-	/* Read sink pages have been moved from rqstp->rq_pages to
-	 * head->rc_arg.pages. Force svc_recv to refill those slots
-	 * in rq_pages.
-	 */
-	for (page = rqstp->rq_pages; page < rqstp->rq_respages; page++)
-		*page = NULL;
-
 	if (ret < 0)
-		svc_rdma_read_info_free(info);
+		goto out_err;
+	return 0;
+
+out_err:
+	svc_rdma_read_info_free(info);
 	return ret;
 }
diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
index ffef0c508f1a..8602a5f1b515 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
@@ -656,7 +656,9 @@ static void svc_rdma_save_io_pages(struct svc_rqst *rqstp,
 		ctxt->sc_pages[i] = rqstp->rq_respages[i];
 		rqstp->rq_respages[i] = NULL;
 	}
-	rqstp->rq_next_page = rqstp->rq_respages + 1;
+
+	/* Prevent svc_xprt_release from releasing pages in rq_pages */
+	rqstp->rq_next_page = rqstp->rq_respages;
 }
 
 /* Prepare the portion of the RPC Reply that will be transmitted
diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
index 547b2cdf1427..2848cafd4a17 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_transport.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
@@ -296,7 +296,6 @@ static int rdma_listen_handler(struct rdma_cm_id *cma_id,
 			       struct rdma_cm_event *event)
 {
 	struct sockaddr *sap = (struct sockaddr *)&cma_id->route.addr.src_addr;
-	int ret = 0;
 
 	trace_svcrdma_cm_event(event, sap);
 
@@ -315,7 +314,7 @@ static int rdma_listen_handler(struct rdma_cm_id *cma_id,
 		break;
 	}
 
-	return ret;
+	return 0;
 }
 
 static int rdma_cma_handler(struct rdma_cm_id *cma_id,