From 2d8ae8c417db284f598dffb178cc01e7db0f1821 Mon Sep 17 00:00:00 2001
From: Christian Brauner <brauner@kernel.org>
Date: Tue, 2 May 2023 15:36:02 +0200
Subject: nfsd: use vfs setgid helper

We've aligned setgid behavior over multiple kernel releases. The details
can be found in commit cf619f891971 ("Merge tag 'fs.ovl.setgid.v6.2' of
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping") and
commit 426b4ca2d6a5 ("Merge tag 'fs.setgid.v6.0' of
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux").
Consistent setgid stripping behavior is now encapsulated in the
setattr_should_drop_sgid() helper which is used by all filesystems that
strip setgid bits outside of vfs proper. Usually ATTR_KILL_SGID is
raised in e.g., chown_common() and is subject to the
setattr_should_drop_sgid() check to determine whether the setgid bit can
be retained. Since nfsd is raising ATTR_KILL_SGID unconditionally it
will cause notify_change() to strip it even if the caller had the
necessary privileges to retain it. Ensure that nfsd only raises
ATR_KILL_SGID if the caller lacks the necessary privileges to retain the
setgid bit.

Without this patch the setgid stripping tests in LTP will fail:

> As you can see, the problem is S_ISGID (0002000) was dropped on a
> non-group-executable file while chown was invoked by super-user, while

[...]

> fchown02.c:66: TFAIL: testfile2: wrong mode permissions 0100700, expected 0102700

[...]

> chown02.c:57: TFAIL: testfile2: wrong mode permissions 0100700, expected 0102700

With this patch all tests pass.

Reported-by: Sherry Yang <sherry.yang@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/vfs.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index db67f8e19344..0016bcc04a59 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -388,7 +388,9 @@ nfsd_sanitize_attrs(struct inode *inode, struct iattr *iap)
 				iap->ia_mode &= ~S_ISGID;
 		} else {
 			/* set ATTR_KILL_* bits and let VFS handle it */
-			iap->ia_valid |= (ATTR_KILL_SUID | ATTR_KILL_SGID);
+			iap->ia_valid |= ATTR_KILL_SUID;
+			iap->ia_valid |=
+				setattr_should_drop_sgid(&nop_mnt_idmap, inode);
 		}
 	}
 }
-- 
cgit v1.2.3


From fc80fc2d4e39137869da3150ee169b40bf879287 Mon Sep 17 00:00:00 2001
From: Ding Hui <dinghui@sangfor.com.cn>
Date: Mon, 15 May 2023 10:13:07 +0800
Subject: SUNRPC: Fix UAF in svc_tcp_listen_data_ready()

After the listener svc_sock is freed, and before invoking svc_tcp_accept()
for the established child sock, there is a window that the newsock
retaining a freed listener svc_sock in sk_user_data which cloning from
parent. In the race window, if data is received on the newsock, we will
observe use-after-free report in svc_tcp_listen_data_ready().

Reproduce by two tasks:

1. while :; do rpc.nfsd 0 ; rpc.nfsd; done
2. while :; do echo "" | ncat -4 127.0.0.1 2049 ; done

KASAN report:

  ==================================================================
  BUG: KASAN: slab-use-after-free in svc_tcp_listen_data_ready+0x1cf/0x1f0 [sunrpc]
  Read of size 8 at addr ffff888139d96228 by task nc/102553
  CPU: 7 PID: 102553 Comm: nc Not tainted 6.3.0+ #18
  Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
  Call Trace:
   <IRQ>
   dump_stack_lvl+0x33/0x50
   print_address_description.constprop.0+0x27/0x310
   print_report+0x3e/0x70
   kasan_report+0xae/0xe0
   svc_tcp_listen_data_ready+0x1cf/0x1f0 [sunrpc]
   tcp_data_queue+0x9f4/0x20e0
   tcp_rcv_established+0x666/0x1f60
   tcp_v4_do_rcv+0x51c/0x850
   tcp_v4_rcv+0x23fc/0x2e80
   ip_protocol_deliver_rcu+0x62/0x300
   ip_local_deliver_finish+0x267/0x350
   ip_local_deliver+0x18b/0x2d0
   ip_rcv+0x2fb/0x370
   __netif_receive_skb_one_core+0x166/0x1b0
   process_backlog+0x24c/0x5e0
   __napi_poll+0xa2/0x500
   net_rx_action+0x854/0xc90
   __do_softirq+0x1bb/0x5de
   do_softirq+0xcb/0x100
   </IRQ>
   <TASK>
   ...
   </TASK>

  Allocated by task 102371:
   kasan_save_stack+0x1e/0x40
   kasan_set_track+0x21/0x30
   __kasan_kmalloc+0x7b/0x90
   svc_setup_socket+0x52/0x4f0 [sunrpc]
   svc_addsock+0x20d/0x400 [sunrpc]
   __write_ports_addfd+0x209/0x390 [nfsd]
   write_ports+0x239/0x2c0 [nfsd]
   nfsctl_transaction_write+0xac/0x110 [nfsd]
   vfs_write+0x1c3/0xae0
   ksys_write+0xed/0x1c0
   do_syscall_64+0x38/0x90
   entry_SYSCALL_64_after_hwframe+0x72/0xdc

  Freed by task 102551:
   kasan_save_stack+0x1e/0x40
   kasan_set_track+0x21/0x30
   kasan_save_free_info+0x2a/0x50
   __kasan_slab_free+0x106/0x190
   __kmem_cache_free+0x133/0x270
   svc_xprt_free+0x1e2/0x350 [sunrpc]
   svc_xprt_destroy_all+0x25a/0x440 [sunrpc]
   nfsd_put+0x125/0x240 [nfsd]
   nfsd_svc+0x2cb/0x3c0 [nfsd]
   write_threads+0x1ac/0x2a0 [nfsd]
   nfsctl_transaction_write+0xac/0x110 [nfsd]
   vfs_write+0x1c3/0xae0
   ksys_write+0xed/0x1c0
   do_syscall_64+0x38/0x90
   entry_SYSCALL_64_after_hwframe+0x72/0xdc

Fix the UAF by simply doing nothing in svc_tcp_listen_data_ready()
if state != TCP_LISTEN, that will avoid dereferencing svsk for all
child socket.

Link: https://lore.kernel.org/lkml/20230507091131.23540-1-dinghui@sangfor.com.cn/
Fixes: fa9251afc33c ("SUNRPC: Call the default socket callbacks instead of open coding")
Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 net/sunrpc/svcsock.c | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index f77cebe2c071..15f4d0d40bdd 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -826,12 +826,6 @@ static void svc_tcp_listen_data_ready(struct sock *sk)
 
 	trace_sk_data_ready(sk);
 
-	if (svsk) {
-		/* Refer to svc_setup_socket() for details. */
-		rmb();
-		svsk->sk_odata(sk);
-	}
-
 	/*
 	 * This callback may called twice when a new connection
 	 * is established as a child socket inherits everything
@@ -840,13 +834,18 @@ static void svc_tcp_listen_data_ready(struct sock *sk)
 	 *    when one of child sockets become ESTABLISHED.
 	 * 2) data_ready method of the child socket may be called
 	 *    when it receives data before the socket is accepted.
-	 * In case of 2, we should ignore it silently.
+	 * In case of 2, we should ignore it silently and DO NOT
+	 * dereference svsk.
 	 */
-	if (sk->sk_state == TCP_LISTEN) {
-		if (svsk) {
-			set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
-			svc_xprt_enqueue(&svsk->sk_xprt);
-		}
+	if (sk->sk_state != TCP_LISTEN)
+		return;
+
+	if (svsk) {
+		/* Refer to svc_setup_socket() for details. */
+		rmb();
+		svsk->sk_odata(sk);
+		set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
+		svc_xprt_enqueue(&svsk->sk_xprt);
 	}
 }
 
-- 
cgit v1.2.3


From e8277327d74fb28bf46969ad68a225272f04c318 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Mon, 15 May 2023 09:32:41 -0400
Subject: SUNRPC: Fix an incorrect comment

The correct function name is svc_tcp_listen_data_ready().

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 net/sunrpc/svcsock.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 15f4d0d40bdd..a2d0bf429347 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -1463,7 +1463,7 @@ static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
 	svsk->sk_owspace = inet->sk_write_space;
 	/*
 	 * This barrier is necessary in order to prevent race condition
-	 * with svc_data_ready(), svc_listen_data_ready() and others
+	 * with svc_data_ready(), svc_tcp_listen_data_ready(), and others
 	 * when calling callbacks above.
 	 */
 	wmb();
-- 
cgit v1.2.3


From cce4ee9c7834f68cf6a221d61d614c2748611c1c Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Mon, 15 May 2023 09:32:47 -0400
Subject: SUNRPC: Remove dprintk() in svc_handle_xprt()

When enabled, this dprintk() fires for every incoming RPC, which is
an enormous amount of log traffic. These days, after the first few
hundred log messages, the system journald is just going to mute it,
along with all other NFSD debug output.

Let's rely on trace points for this high-traffic information
instead.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 net/sunrpc/svc_xprt.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 13a14897bc17..42536a0b1db4 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -843,9 +843,6 @@ static int svc_handle_xprt(struct svc_rqst *rqstp, struct svc_xprt *xprt)
 		svc_xprt_received(xprt);
 	} else if (svc_xprt_reserve_slot(rqstp, xprt)) {
 		/* XPT_DATA|XPT_DEFERRED case: */
-		dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
-			rqstp, rqstp->rq_pool->sp_id, xprt,
-			kref_read(&xprt->xpt_ref));
 		rqstp->rq_deferred = svc_deferred_dequeue(xprt);
 		if (rqstp->rq_deferred)
 			len = svc_deferred_recv(rqstp);
-- 
cgit v1.2.3


From d7900daea0b9818cd1cbeb9c5bd94653c487b0e4 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Mon, 15 May 2023 09:32:53 -0400
Subject: SUNRPC: Improve observability in svc_tcp_accept()

The -ENOMEM arm could fire repeatedly if the system runs low on
memory, so remove it.

Don't bother to trace -EAGAIN error events, since those fire after
a listener is created (with no work done) and once again after an
accept has been handled successfully (again, with no work done).

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 net/sunrpc/svcsock.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index a2d0bf429347..fbe33c922882 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -886,13 +886,8 @@ static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
 	clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 	err = kernel_accept(sock, &newsock, O_NONBLOCK);
 	if (err < 0) {
-		if (err == -ENOMEM)
-			printk(KERN_WARNING "%s: no more sockets!\n",
-			       serv->sv_name);
-		else if (err != -EAGAIN)
-			net_warn_ratelimited("%s: accept failed (err %d)!\n",
-					     serv->sv_name, -err);
-		trace_svcsock_accept_err(xprt, serv->sv_name, err);
+		if (err != -EAGAIN)
+			trace_svcsock_accept_err(xprt, serv->sv_name, err);
 		return NULL;
 	}
 	if (IS_ERR(sock_alloc_file(newsock, O_NONBLOCK, NULL)))
-- 
cgit v1.2.3


From c42bebca967da88c054ccb5ab152c9822c054662 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Mon, 15 May 2023 09:33:00 -0400
Subject: SUNRPC: Trace struct svc_sock lifetime events

Capture a timestamp and pointer address during the creation and
destruction of struct svc_sock to record its lifetime. This helps
to diagnose transport reference counting issues.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 include/trace/events/sunrpc.h | 39 +++++++++++++++++++++++++++------------
 net/sunrpc/svcsock.c          |  4 +++-
 2 files changed, 30 insertions(+), 13 deletions(-)

diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h
index 31bc7025cb44..69e42ef30979 100644
--- a/include/trace/events/sunrpc.h
+++ b/include/trace/events/sunrpc.h
@@ -2104,31 +2104,46 @@ DEFINE_SVC_DEFERRED_EVENT(drop);
 DEFINE_SVC_DEFERRED_EVENT(queue);
 DEFINE_SVC_DEFERRED_EVENT(recv);
 
-TRACE_EVENT(svcsock_new_socket,
+DECLARE_EVENT_CLASS(svcsock_lifetime_class,
 	TP_PROTO(
+		const void *svsk,
 		const struct socket *socket
 	),
-
-	TP_ARGS(socket),
-
+	TP_ARGS(svsk, socket),
 	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__field(const void *, svsk)
+		__field(const void *, sk)
 		__field(unsigned long, type)
 		__field(unsigned long, family)
-		__field(bool, listener)
+		__field(unsigned long, state)
 	),
-
 	TP_fast_assign(
+		struct sock *sk = socket->sk;
+
+		__entry->netns_ino = sock_net(sk)->ns.inum;
+		__entry->svsk = svsk;
+		__entry->sk = sk;
 		__entry->type = socket->type;
-		__entry->family = socket->sk->sk_family;
-		__entry->listener = (socket->sk->sk_state == TCP_LISTEN);
+		__entry->family = sk->sk_family;
+		__entry->state = sk->sk_state;
 	),
-
-	TP_printk("type=%s family=%s%s",
-		show_socket_type(__entry->type),
+	TP_printk("svsk=%p type=%s family=%s%s",
+		__entry->svsk, show_socket_type(__entry->type),
 		rpc_show_address_family(__entry->family),
-		__entry->listener ? " (listener)" : ""
+		__entry->state == TCP_LISTEN ? " (listener)" : ""
 	)
 );
+#define DEFINE_SVCSOCK_LIFETIME_EVENT(name) \
+	DEFINE_EVENT(svcsock_lifetime_class, name, \
+		TP_PROTO( \
+			const void *svsk, \
+			const struct socket *socket \
+		), \
+		TP_ARGS(svsk, socket))
+
+DEFINE_SVCSOCK_LIFETIME_EVENT(svcsock_new);
+DEFINE_SVCSOCK_LIFETIME_EVENT(svcsock_free);
 
 TRACE_EVENT(svcsock_marker,
 	TP_PROTO(
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index fbe33c922882..5f519fc0541b 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -1470,7 +1470,7 @@ static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
 	else
 		svc_tcp_init(svsk, serv);
 
-	trace_svcsock_new_socket(sock);
+	trace_svcsock_new(svsk, sock);
 	return svsk;
 }
 
@@ -1651,6 +1651,8 @@ static void svc_sock_free(struct svc_xprt *xprt)
 	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 	struct socket *sock = svsk->sk_sock;
 
+	trace_svcsock_free(svsk, sock);
+
 	tls_handshake_cancel(sock->sk);
 	if (sock->file)
 		sockfd_put(sock);
-- 
cgit v1.2.3


From 442a629009818de2f8d9731cafb96e111ca8e4e6 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Mon, 15 May 2023 09:35:38 -0400
Subject: NFSD: Clean up nfsctl white-space damage

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfsctl.c | 38 +++++++++++++++++++-------------------
 1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index b4fd7a7062d5..2ecea3b318eb 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -324,7 +324,7 @@ static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
 	len = qword_get(&mesg, dname, size);
 	if (len <= 0)
 		return -EINVAL;
-	
+
 	path = dname+len+1;
 	len = qword_get(&mesg, path, size);
 	if (len <= 0)
@@ -338,7 +338,7 @@ static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
 		return -EINVAL;
 	maxsize = min(maxsize, NFS3_FHSIZE);
 
-	if (qword_get(&mesg, mesg, size)>0)
+	if (qword_get(&mesg, mesg, size) > 0)
 		return -EINVAL;
 
 	/* we have all the words, they are in buf.. */
@@ -346,7 +346,7 @@ static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
 	if (!dom)
 		return -ENOMEM;
 
-	len = exp_rootfh(netns(file), dom, path, &fh,  maxsize);
+	len = exp_rootfh(netns(file), dom, path, &fh, maxsize);
 	auth_domain_put(dom);
 	if (len)
 		return len;
@@ -418,8 +418,8 @@ static ssize_t write_threads(struct file *file, char *buf, size_t size)
  * OR
  *
  * Input:
- * 			buf:		C string containing whitespace-
- * 					separated unsigned integer values
+ *			buf:		C string containing whitespace-
+ *					separated unsigned integer values
  *					representing the number of NFSD
  *					threads to start in each pool
  *			size:		non-zero length of C string in @buf
@@ -526,7 +526,7 @@ static ssize_t __write_versions(struct file *file, char *buf, size_t size)
 	char *sep;
 	struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
 
-	if (size>0) {
+	if (size > 0) {
 		if (nn->nfsd_serv)
 			/* Cannot change versions without updating
 			 * nn->nfsd_serv->sv_xdrsize, and reallocing
@@ -637,11 +637,11 @@ out:
  * OR
  *
  * Input:
- * 			buf:		C string containing whitespace-
- * 					separated positive or negative
- * 					integer values representing NFS
- * 					protocol versions to enable ("+n")
- * 					or disable ("-n")
+ *			buf:		C string containing whitespace-
+ *					separated positive or negative
+ *					integer values representing NFS
+ *					protocol versions to enable ("+n")
+ *					or disable ("-n")
  *			size:		non-zero length of C string in @buf
  * Output:
  *	On success:	status of zero or more protocol versions has
@@ -705,7 +705,7 @@ static ssize_t __write_ports_addfd(char *buf, struct net *net, const struct cred
 }
 
 /*
- * A transport listener is added by writing it's transport name and
+ * A transport listener is added by writing its transport name and
  * a port number.
  */
 static ssize_t __write_ports_addxprt(char *buf, struct net *net, const struct cred *cred)
@@ -832,9 +832,9 @@ int nfsd_max_blksize;
  * OR
  *
  * Input:
- * 			buf:		C string containing an unsigned
- * 					integer value representing the new
- * 					NFS blksize
+ *			buf:		C string containing an unsigned
+ *					integer value representing the new
+ *					NFS blksize
  *			size:		non-zero length of C string in @buf
  * Output:
  *	On success:	passed-in buffer filled with '\n'-terminated C string
@@ -881,9 +881,9 @@ static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
  * OR
  *
  * Input:
- * 			buf:		C string containing an unsigned
- * 					integer value representing the new
- * 					number of max connections
+ *			buf:		C string containing an unsigned
+ *					integer value representing the new
+ *					number of max connections
  *			size:		non-zero length of C string in @buf
  * Output:
  *	On success:	passed-in buffer filled with '\n'-terminated C string
@@ -1065,7 +1065,7 @@ static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
  * OR
  *
  * Input:
- * 			buf:		any value
+ *			buf:		any value
  *			size:		non-zero length of C string in @buf
  * Output:
  *			passed-in buffer filled with "Y" or "N" with a newline
-- 
cgit v1.2.3


From 3434d7aa77d24c5c4b3d4385084cfdb607f05dec Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Mon, 15 May 2023 09:35:44 -0400
Subject: NFSD: Clean up nfsctl_transaction_write()

For easier readability, follow the common convention:

    if (error)
	handle_error;
    continue_normally;

No behavior change is expected.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfsctl.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 2ecea3b318eb..df0aae211a49 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -109,12 +109,12 @@ static ssize_t nfsctl_transaction_write(struct file *file, const char __user *bu
 	if (IS_ERR(data))
 		return PTR_ERR(data);
 
-	rv =  write_op[ino](file, data, size);
-	if (rv >= 0) {
-		simple_transaction_set(file, rv);
-		rv = size;
-	}
-	return rv;
+	rv = write_op[ino](file, data, size);
+	if (rv < 0)
+		return rv;
+
+	simple_transaction_set(file, rv);
+	return size;
 }
 
 static ssize_t nfsctl_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
-- 
cgit v1.2.3


From 39d432fc76301cf0a0c454022117601994ca9397 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Mon, 15 May 2023 09:35:50 -0400
Subject: NFSD: trace nfsctl operations

Add trace log eye-catchers that record the arguments used to
configure NFSD. This helps when troubleshooting the NFSD
administrative interfaces.

These tracepoints can capture NFSD start-up and shutdown times and
parameters, changes in lease time and thread count, and a request
to end the namespace's NFSv4 grace period, in addition to the set
of NFS versions that are enabled.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfsctl.c |  33 +++++--
 fs/nfsd/trace.h  | 259 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 284 insertions(+), 8 deletions(-)

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index df0aae211a49..1489e0b703b4 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -25,6 +25,7 @@
 #include "netns.h"
 #include "pnfs.h"
 #include "filecache.h"
+#include "trace.h"
 
 /*
  *	We have a single directory with several nodes in it.
@@ -230,6 +231,7 @@ static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size)
 	if (rpc_pton(net, fo_path, size, sap, salen) == 0)
 		return -EINVAL;
 
+	trace_nfsd_ctl_unlock_ip(net, buf);
 	return nlmsvc_unlock_all_by_ip(sap);
 }
 
@@ -263,7 +265,7 @@ static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size)
 	fo_path = buf;
 	if (qword_get(&buf, fo_path, size) < 0)
 		return -EINVAL;
-
+	trace_nfsd_ctl_unlock_fs(netns(file), fo_path);
 	error = kern_path(fo_path, 0, &path);
 	if (error)
 		return error;
@@ -341,6 +343,8 @@ static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
 	if (qword_get(&mesg, mesg, size) > 0)
 		return -EINVAL;
 
+	trace_nfsd_ctl_filehandle(netns(file), dname, path, maxsize);
+
 	/* we have all the words, they are in buf.. */
 	dom = unix_domain_find(dname);
 	if (!dom)
@@ -399,6 +403,7 @@ static ssize_t write_threads(struct file *file, char *buf, size_t size)
 			return rv;
 		if (newthreads < 0)
 			return -EINVAL;
+		trace_nfsd_ctl_threads(net, newthreads);
 		rv = nfsd_svc(newthreads, net, file->f_cred);
 		if (rv < 0)
 			return rv;
@@ -471,6 +476,7 @@ static ssize_t write_pool_threads(struct file *file, char *buf, size_t size)
 			rv = -EINVAL;
 			if (nthreads[i] < 0)
 				goto out_free;
+			trace_nfsd_ctl_pool_threads(net, i, nthreads[i]);
 		}
 		rv = nfsd_set_nrthreads(i, nthreads, net);
 		if (rv)
@@ -536,6 +542,7 @@ static ssize_t __write_versions(struct file *file, char *buf, size_t size)
 		if (buf[size-1] != '\n')
 			return -EINVAL;
 		buf[size-1] = 0;
+		trace_nfsd_ctl_version(netns(file), buf);
 
 		vers = mesg;
 		len = qword_get(&mesg, vers, size);
@@ -689,6 +696,7 @@ static ssize_t __write_ports_addfd(char *buf, struct net *net, const struct cred
 	err = get_int(&mesg, &fd);
 	if (err != 0 || fd < 0)
 		return -EINVAL;
+	trace_nfsd_ctl_ports_addfd(net, fd);
 
 	err = nfsd_create_serv(net);
 	if (err != 0)
@@ -720,6 +728,7 @@ static ssize_t __write_ports_addxprt(char *buf, struct net *net, const struct cr
 
 	if (port < 1 || port > USHRT_MAX)
 		return -EINVAL;
+	trace_nfsd_ctl_ports_addxprt(net, transport, port);
 
 	err = nfsd_create_serv(net);
 	if (err != 0)
@@ -853,6 +862,8 @@ static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
 		int rv = get_int(&mesg, &bsize);
 		if (rv)
 			return rv;
+		trace_nfsd_ctl_maxblksize(netns(file), bsize);
+
 		/* force bsize into allowed range and
 		 * required alignment.
 		 */
@@ -903,6 +914,7 @@ static ssize_t write_maxconn(struct file *file, char *buf, size_t size)
 
 		if (rv)
 			return rv;
+		trace_nfsd_ctl_maxconn(netns(file), maxconn);
 		nn->max_connections = maxconn;
 	}
 
@@ -913,6 +925,7 @@ static ssize_t write_maxconn(struct file *file, char *buf, size_t size)
 static ssize_t __nfsd4_write_time(struct file *file, char *buf, size_t size,
 				  time64_t *time, struct nfsd_net *nn)
 {
+	struct dentry *dentry = file_dentry(file);
 	char *mesg = buf;
 	int rv, i;
 
@@ -922,6 +935,9 @@ static ssize_t __nfsd4_write_time(struct file *file, char *buf, size_t size,
 		rv = get_int(&mesg, &i);
 		if (rv)
 			return rv;
+		trace_nfsd_ctl_time(netns(file), dentry->d_name.name,
+				    dentry->d_name.len, i);
+
 		/*
 		 * Some sanity checking.  We don't have a reason for
 		 * these particular numbers, but problems with the
@@ -1014,6 +1030,7 @@ static ssize_t __write_recoverydir(struct file *file, char *buf, size_t size,
 		len = qword_get(&mesg, recdir, size);
 		if (len <= 0)
 			return -EINVAL;
+		trace_nfsd_ctl_recoverydir(netns(file), recdir);
 
 		status = nfs4_reset_recoverydir(recdir);
 		if (status)
@@ -1087,7 +1104,7 @@ static ssize_t write_v4_end_grace(struct file *file, char *buf, size_t size)
 		case '1':
 			if (!nn->nfsd_serv)
 				return -EBUSY;
-			nfsd4_end_grace(nn);
+			trace_nfsd_end_grace(netns(file));
 			break;
 		default:
 			return -EINVAL;
@@ -1192,8 +1209,8 @@ static int __nfsd_symlink(struct inode *dir, struct dentry *dentry,
  * @content is assumed to be a NUL-terminated string that lives
  * longer than the symlink itself.
  */
-static void nfsd_symlink(struct dentry *parent, const char *name,
-			 const char *content)
+static void _nfsd_symlink(struct dentry *parent, const char *name,
+			  const char *content)
 {
 	struct inode *dir = parent->d_inode;
 	struct dentry *dentry;
@@ -1210,8 +1227,8 @@ out:
 	inode_unlock(dir);
 }
 #else
-static inline void nfsd_symlink(struct dentry *parent, const char *name,
-				const char *content)
+static inline void _nfsd_symlink(struct dentry *parent, const char *name,
+				 const char *content)
 {
 }
 
@@ -1389,8 +1406,8 @@ static int nfsd_fill_super(struct super_block *sb, struct fs_context *fc)
 	ret = simple_fill_super(sb, 0x6e667364, nfsd_files);
 	if (ret)
 		return ret;
-	nfsd_symlink(sb->s_root, "supported_krb5_enctypes",
-		     "/proc/net/rpc/gss_krb5_enctypes");
+	_nfsd_symlink(sb->s_root, "supported_krb5_enctypes",
+		      "/proc/net/rpc/gss_krb5_enctypes");
 	dentry = nfsd_mkdir(sb->s_root, NULL, "clients");
 	if (IS_ERR(dentry))
 		return PTR_ERR(dentry);
diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index 72a906a053dc..2af74983f146 100644
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -1581,6 +1581,265 @@ TRACE_EVENT(nfsd_cb_recall_any_done,
 	)
 );
 
+TRACE_EVENT(nfsd_ctl_unlock_ip,
+	TP_PROTO(
+		const struct net *net,
+		const char *address
+	),
+	TP_ARGS(net, address),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__string(address, address)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__assign_str(address, address);
+	),
+	TP_printk("address=%s",
+		__get_str(address)
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_unlock_fs,
+	TP_PROTO(
+		const struct net *net,
+		const char *path
+	),
+	TP_ARGS(net, path),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__string(path, path)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__assign_str(path, path);
+	),
+	TP_printk("path=%s",
+		__get_str(path)
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_filehandle,
+	TP_PROTO(
+		const struct net *net,
+		const char *domain,
+		const char *path,
+		int maxsize
+	),
+	TP_ARGS(net, domain, path, maxsize),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__field(int, maxsize)
+		__string(domain, domain)
+		__string(path, path)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__entry->maxsize = maxsize;
+		__assign_str(domain, domain);
+		__assign_str(path, path);
+	),
+	TP_printk("domain=%s path=%s maxsize=%d",
+		__get_str(domain), __get_str(path), __entry->maxsize
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_threads,
+	TP_PROTO(
+		const struct net *net,
+		int newthreads
+	),
+	TP_ARGS(net, newthreads),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__field(int, newthreads)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__entry->newthreads = newthreads;
+	),
+	TP_printk("newthreads=%d",
+		__entry->newthreads
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_pool_threads,
+	TP_PROTO(
+		const struct net *net,
+		int pool,
+		int nrthreads
+	),
+	TP_ARGS(net, pool, nrthreads),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__field(int, pool)
+		__field(int, nrthreads)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__entry->pool = pool;
+		__entry->nrthreads = nrthreads;
+	),
+	TP_printk("pool=%d nrthreads=%d",
+		__entry->pool, __entry->nrthreads
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_version,
+	TP_PROTO(
+		const struct net *net,
+		const char *mesg
+	),
+	TP_ARGS(net, mesg),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__string(mesg, mesg)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__assign_str(mesg, mesg);
+	),
+	TP_printk("%s",
+		__get_str(mesg)
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_ports_addfd,
+	TP_PROTO(
+		const struct net *net,
+		int fd
+	),
+	TP_ARGS(net, fd),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__field(int, fd)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__entry->fd = fd;
+	),
+	TP_printk("fd=%d",
+		__entry->fd
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_ports_addxprt,
+	TP_PROTO(
+		const struct net *net,
+		const char *transport,
+		int port
+	),
+	TP_ARGS(net, transport, port),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__field(int, port)
+		__string(transport, transport)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__entry->port = port;
+		__assign_str(transport, transport);
+	),
+	TP_printk("transport=%s port=%d",
+		__get_str(transport), __entry->port
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_maxblksize,
+	TP_PROTO(
+		const struct net *net,
+		int bsize
+	),
+	TP_ARGS(net, bsize),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__field(int, bsize)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__entry->bsize = bsize;
+	),
+	TP_printk("bsize=%d",
+		__entry->bsize
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_maxconn,
+	TP_PROTO(
+		const struct net *net,
+		int maxconn
+	),
+	TP_ARGS(net, maxconn),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__field(int, maxconn)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__entry->maxconn = maxconn;
+	),
+	TP_printk("maxconn=%d",
+		__entry->maxconn
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_time,
+	TP_PROTO(
+		const struct net *net,
+		const char *name,
+		size_t namelen,
+		int time
+	),
+	TP_ARGS(net, name, namelen, time),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__field(int, time)
+		__string_len(name, name, namelen)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__entry->time = time;
+		__assign_str_len(name, name, namelen);
+	),
+	TP_printk("file=%s time=%d\n",
+		__get_str(name), __entry->time
+	)
+);
+
+TRACE_EVENT(nfsd_ctl_recoverydir,
+	TP_PROTO(
+		const struct net *net,
+		const char *recdir
+	),
+	TP_ARGS(net, recdir),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__string(recdir, recdir)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+		__assign_str(recdir, recdir);
+	),
+	TP_printk("recdir=%s",
+		__get_str(recdir)
+	)
+);
+
+TRACE_EVENT(nfsd_end_grace,
+	TP_PROTO(
+		const struct net *net
+	),
+	TP_ARGS(net),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = net->ns.inum;
+	),
+	TP_printk("nn=%d", __entry->netns_ino
+	)
+);
+
 #endif /* _NFSD_TRACE_H */
 
 #undef TRACE_INCLUDE_PATH
-- 
cgit v1.2.3


From 5f7fc5d69f6e92ec0b38774c387f5cf7812c5806 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Mon, 15 May 2023 09:47:29 -0400
Subject: SUNRPC: Resupply rq_pages from node-local memory

svc_init_buffer() is careful to allocate the initial set of server
thread buffer pages from memory on the local NUMA node.
svc_alloc_arg() should also be that careful.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 net/sunrpc/svc_xprt.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 42536a0b1db4..9ca3393a197e 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -685,8 +685,9 @@ static int svc_alloc_arg(struct svc_rqst *rqstp)
 	}
 
 	for (filled = 0; filled < pages; filled = ret) {
-		ret = alloc_pages_bulk_array(GFP_KERNEL, pages,
-					     rqstp->rq_pages);
+		ret = alloc_pages_bulk_array_node(GFP_KERNEL,
+						  rqstp->rq_pool->sp_id,
+						  pages, rqstp->rq_pages);
 		if (ret > filled)
 			/* Made progress, don't sleep yet */
 			continue;
-- 
cgit v1.2.3


From 88e4d41a264d00fbfd344eb2485c1c59096197f4 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Mon, 15 May 2023 09:47:36 -0400
Subject: SUNRPC: Use __alloc_bulk_pages() in svc_init_buffer()

Clean up: Use the bulk page allocator when filling a server thread's
buffer page array.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 net/sunrpc/svc.c | 23 +++++++----------------
 1 file changed, 7 insertions(+), 16 deletions(-)

diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 79967b6925bd..e6d4cec61e47 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -597,34 +597,25 @@ svc_destroy(struct kref *ref)
 }
 EXPORT_SYMBOL_GPL(svc_destroy);
 
-/*
- * Allocate an RPC server's buffer space.
- * We allocate pages and place them in rq_pages.
- */
-static int
+static bool
 svc_init_buffer(struct svc_rqst *rqstp, unsigned int size, int node)
 {
-	unsigned int pages, arghi;
+	unsigned long pages, ret;
 
 	/* bc_xprt uses fore channel allocated buffers */
 	if (svc_is_backchannel(rqstp))
-		return 1;
+		return true;
 
 	pages = size / PAGE_SIZE + 1; /* extra page as we hold both request and reply.
 				       * We assume one is at most one page
 				       */
-	arghi = 0;
 	WARN_ON_ONCE(pages > RPCSVC_MAXPAGES);
 	if (pages > RPCSVC_MAXPAGES)
 		pages = RPCSVC_MAXPAGES;
-	while (pages) {
-		struct page *p = alloc_pages_node(node, GFP_KERNEL, 0);
-		if (!p)
-			break;
-		rqstp->rq_pages[arghi++] = p;
-		pages--;
-	}
-	return pages == 0;
+
+	ret = alloc_pages_bulk_array_node(GFP_KERNEL, node, pages,
+					  rqstp->rq_pages);
+	return ret == pages;
 }
 
 /*
-- 
cgit v1.2.3


From adaa7a50d027b91ee6d56ae8b0a3f6edf5a78776 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Tue, 16 May 2023 10:26:09 -0400
Subject: NFSD: Add encoders for NFSv4 clientids and verifiers

Deduplicate some common code.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs4xdr.c | 107 ++++++++++++++++++++++++++++--------------------------
 1 file changed, 55 insertions(+), 52 deletions(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 76db2fe29624..1488ce978f7c 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3688,6 +3688,30 @@ fail:
 	return -EINVAL;
 }
 
+static __be32
+nfsd4_encode_verifier4(struct xdr_stream *xdr, const nfs4_verifier *verf)
+{
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
+	if (!p)
+		return nfserr_resource;
+	memcpy(p, verf->data, sizeof(verf->data));
+	return nfs_ok;
+}
+
+static __be32
+nfsd4_encode_clientid4(struct xdr_stream *xdr, const clientid_t *clientid)
+{
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, sizeof(__be64));
+	if (!p)
+		return nfserr_resource;
+	memcpy(p, clientid, sizeof(*clientid));
+	return nfs_ok;
+}
+
 static __be32
 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
 {
@@ -3752,15 +3776,8 @@ nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr,
 		    union nfsd4_op_u *u)
 {
 	struct nfsd4_commit *commit = &u->commit;
-	struct xdr_stream *xdr = resp->xdr;
-	__be32 *p;
 
-	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
-	if (!p)
-		return nfserr_resource;
-	p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
-						NFS4_VERIFIER_SIZE);
-	return 0;
+	return nfsd4_encode_verifier4(resp->xdr, &commit->co_verf);
 }
 
 static __be32
@@ -4213,15 +4230,9 @@ nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr,
 	int starting_len = xdr->buf->len;
 	__be32 *p;
 
-	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
-	if (!p)
-		return nfserr_resource;
-
-	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
-	*p++ = cpu_to_be32(0);
-	*p++ = cpu_to_be32(0);
-	xdr->buf->head[0].iov_len = (char *)xdr->p -
-				    (char *)xdr->buf->head[0].iov_base;
+	nfserr = nfsd4_encode_verifier4(xdr, &readdir->rd_verf);
+	if (nfserr != nfs_ok)
+		return nfserr;
 
 	/*
 	 * Number of bytes left for directory entries allowing for the
@@ -4448,23 +4459,25 @@ nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr,
 {
 	struct nfsd4_setclientid *scd = &u->setclientid;
 	struct xdr_stream *xdr = resp->xdr;
-	__be32 *p;
 
 	if (!nfserr) {
-		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
-		if (!p)
-			return nfserr_resource;
-		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
-		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
-						NFS4_VERIFIER_SIZE);
-	}
-	else if (nfserr == nfserr_clid_inuse) {
-		p = xdr_reserve_space(xdr, 8);
-		if (!p)
-			return nfserr_resource;
-		*p++ = cpu_to_be32(0);
-		*p++ = cpu_to_be32(0);
+		nfserr = nfsd4_encode_clientid4(xdr, &scd->se_clientid);
+		if (nfserr != nfs_ok)
+			goto out;
+		nfserr = nfsd4_encode_verifier4(xdr, &scd->se_confirm);
+	} else if (nfserr == nfserr_clid_inuse) {
+		/* empty network id */
+		if (xdr_stream_encode_u32(xdr, 0) < 0) {
+			nfserr = nfserr_resource;
+			goto out;
+		}
+		/* empty universal address */
+		if (xdr_stream_encode_u32(xdr, 0) < 0) {
+			nfserr = nfserr_resource;
+			goto out;
+		}
 	}
+out:
 	return nfserr;
 }
 
@@ -4473,17 +4486,12 @@ nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr,
 		   union nfsd4_op_u *u)
 {
 	struct nfsd4_write *write = &u->write;
-	struct xdr_stream *xdr = resp->xdr;
-	__be32 *p;
 
-	p = xdr_reserve_space(xdr, 16);
-	if (!p)
+	if (xdr_stream_encode_u32(resp->xdr, write->wr_bytes_written) < 0)
 		return nfserr_resource;
-	*p++ = cpu_to_be32(write->wr_bytes_written);
-	*p++ = cpu_to_be32(write->wr_how_written);
-	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
-						NFS4_VERIFIER_SIZE);
-	return 0;
+	if (xdr_stream_encode_u32(resp->xdr, write->wr_how_written) < 0)
+		return nfserr_resource;
+	return nfsd4_encode_verifier4(resp->xdr, &write->wr_verifier);
 }
 
 static __be32
@@ -4505,20 +4513,15 @@ nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
 	server_scope = nn->nfsd_name;
 	server_scope_sz = strlen(nn->nfsd_name);
 
-	p = xdr_reserve_space(xdr,
-		8 /* eir_clientid */ +
-		4 /* eir_sequenceid */ +
-		4 /* eir_flags */ +
-		4 /* spr_how */);
-	if (!p)
+	if (nfsd4_encode_clientid4(xdr, &exid->clientid) != nfs_ok)
+		return nfserr_resource;
+	if (xdr_stream_encode_u32(xdr, exid->seqid) < 0)
+		return nfserr_resource;
+	if (xdr_stream_encode_u32(xdr, exid->flags) < 0)
 		return nfserr_resource;
 
-	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
-	*p++ = cpu_to_be32(exid->seqid);
-	*p++ = cpu_to_be32(exid->flags);
-
-	*p++ = cpu_to_be32(exid->spa_how);
-
+	if (xdr_stream_encode_u32(xdr, exid->spa_how) < 0)
+		return nfserr_resource;
 	switch (exid->spa_how) {
 	case SP4_NONE:
 		break;
-- 
cgit v1.2.3


From 66a21db7db59f279a9fcb6445fa36dc6eb001b3c Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Tue, 16 May 2023 10:26:15 -0400
Subject: NFSD: Replace encode_cinfo()

De-duplicate "reserve_space; encode_cinfo".

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs4xdr.c | 72 +++++++++++++++++++------------------------------------
 1 file changed, 24 insertions(+), 48 deletions(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 1488ce978f7c..c5c6873b938d 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2566,12 +2566,16 @@ static __be32 *encode_time_delta(__be32 *p, struct inode *inode)
 	return p;
 }
 
-static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
+static __be32
+nfsd4_encode_change_info4(struct xdr_stream *xdr, struct nfsd4_change_info *c)
 {
-	*p++ = cpu_to_be32(c->atomic);
-	p = xdr_encode_hyper(p, c->before_change);
-	p = xdr_encode_hyper(p, c->after_change);
-	return p;
+	if (xdr_stream_encode_bool(xdr, c->atomic) < 0)
+		return nfserr_resource;
+	if (xdr_stream_encode_u64(xdr, c->before_change) < 0)
+		return nfserr_resource;
+	if (xdr_stream_encode_u64(xdr, c->after_change) < 0)
+		return nfserr_resource;
+	return nfs_ok;
 }
 
 /* Encode as an array of strings the string given with components
@@ -3786,12 +3790,10 @@ nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr,
 {
 	struct nfsd4_create *create = &u->create;
 	struct xdr_stream *xdr = resp->xdr;
-	__be32 *p;
 
-	p = xdr_reserve_space(xdr, 20);
-	if (!p)
-		return nfserr_resource;
-	encode_cinfo(p, &create->cr_cinfo);
+	nfserr = nfsd4_encode_change_info4(xdr, &create->cr_cinfo);
+	if (nfserr)
+		return nfserr;
 	return nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
 			create->cr_bmval[1], create->cr_bmval[2]);
 }
@@ -3909,13 +3911,8 @@ nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr,
 {
 	struct nfsd4_link *link = &u->link;
 	struct xdr_stream *xdr = resp->xdr;
-	__be32 *p;
 
-	p = xdr_reserve_space(xdr, 20);
-	if (!p)
-		return nfserr_resource;
-	p = encode_cinfo(p, &link->li_cinfo);
-	return 0;
+	return nfsd4_encode_change_info4(xdr, &link->li_cinfo);
 }
 
 
@@ -3930,11 +3927,11 @@ nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr,
 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
 	if (nfserr)
 		return nfserr;
-	p = xdr_reserve_space(xdr, 24);
-	if (!p)
+	nfserr = nfsd4_encode_change_info4(xdr, &open->op_cinfo);
+	if (nfserr)
+		return nfserr;
+	if (xdr_stream_encode_u32(xdr, open->op_rflags) < 0)
 		return nfserr_resource;
-	p = encode_cinfo(p, &open->op_cinfo);
-	*p++ = cpu_to_be32(open->op_rflags);
 
 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
 					open->op_bmval[2]);
@@ -4310,13 +4307,8 @@ nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr,
 {
 	struct nfsd4_remove *remove = &u->remove;
 	struct xdr_stream *xdr = resp->xdr;
-	__be32 *p;
 
-	p = xdr_reserve_space(xdr, 20);
-	if (!p)
-		return nfserr_resource;
-	p = encode_cinfo(p, &remove->rm_cinfo);
-	return 0;
+	return nfsd4_encode_change_info4(xdr, &remove->rm_cinfo);
 }
 
 static __be32
@@ -4325,14 +4317,11 @@ nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr,
 {
 	struct nfsd4_rename *rename = &u->rename;
 	struct xdr_stream *xdr = resp->xdr;
-	__be32 *p;
 
-	p = xdr_reserve_space(xdr, 40);
-	if (!p)
-		return nfserr_resource;
-	p = encode_cinfo(p, &rename->rn_sinfo);
-	p = encode_cinfo(p, &rename->rn_tinfo);
-	return 0;
+	nfserr = nfsd4_encode_change_info4(xdr, &rename->rn_sinfo);
+	if (nfserr)
+		return nfserr;
+	return nfsd4_encode_change_info4(xdr, &rename->rn_tinfo);
 }
 
 static __be32
@@ -5102,15 +5091,8 @@ nfsd4_encode_setxattr(struct nfsd4_compoundres *resp, __be32 nfserr,
 {
 	struct nfsd4_setxattr *setxattr = &u->setxattr;
 	struct xdr_stream *xdr = resp->xdr;
-	__be32 *p;
-
-	p = xdr_reserve_space(xdr, 20);
-	if (!p)
-		return nfserr_resource;
 
-	encode_cinfo(p, &setxattr->setxa_cinfo);
-
-	return 0;
+	return nfsd4_encode_change_info4(xdr, &setxattr->setxa_cinfo);
 }
 
 /*
@@ -5256,14 +5238,8 @@ nfsd4_encode_removexattr(struct nfsd4_compoundres *resp, __be32 nfserr,
 {
 	struct nfsd4_removexattr *removexattr = &u->removexattr;
 	struct xdr_stream *xdr = resp->xdr;
-	__be32 *p;
 
-	p = xdr_reserve_space(xdr, 20);
-	if (!p)
-		return nfserr_resource;
-
-	p = encode_cinfo(p, &removexattr->rmxa_cinfo);
-	return 0;
+	return nfsd4_encode_change_info4(xdr, &removexattr->rmxa_cinfo);
 }
 
 typedef __be32(*nfsd4_enc)(struct nfsd4_compoundres *, __be32, union nfsd4_op_u *u);
-- 
cgit v1.2.3


From 82078b9895bd46ce69b4a73e2da40e7e2202fdb5 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Thu, 18 May 2023 13:45:36 -0400
Subject: NFSD: Ensure that xdr_write_pages updates rq_next_page

All other NFSv[23] procedures manage to keep page_ptr and
rq_next_page in lock step.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs3xdr.c          | 11 +++++++----
 fs/nfsd/nfsxdr.c           | 11 +++++++----
 include/linux/sunrpc/svc.h | 21 +++++++++++++++++++++
 3 files changed, 35 insertions(+), 8 deletions(-)

diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c
index 3308dd671ef0..f32128955ec8 100644
--- a/fs/nfsd/nfs3xdr.c
+++ b/fs/nfsd/nfs3xdr.c
@@ -828,7 +828,8 @@ nfs3svc_encode_readlinkres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 			return false;
 		if (xdr_stream_encode_u32(xdr, resp->len) < 0)
 			return false;
-		xdr_write_pages(xdr, resp->pages, 0, resp->len);
+		svcxdr_encode_opaque_pages(rqstp, xdr, resp->pages, 0,
+					   resp->len);
 		if (svc_encode_result_payload(rqstp, head->iov_len, resp->len) < 0)
 			return false;
 		break;
@@ -859,8 +860,9 @@ nfs3svc_encode_readres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 			return false;
 		if (xdr_stream_encode_u32(xdr, resp->count) < 0)
 			return false;
-		xdr_write_pages(xdr, resp->pages, rqstp->rq_res.page_base,
-				resp->count);
+		svcxdr_encode_opaque_pages(rqstp, xdr, resp->pages,
+					   rqstp->rq_res.page_base,
+					   resp->count);
 		if (svc_encode_result_payload(rqstp, head->iov_len, resp->count) < 0)
 			return false;
 		break;
@@ -961,7 +963,8 @@ nfs3svc_encode_readdirres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 			return false;
 		if (!svcxdr_encode_cookieverf3(xdr, resp->verf))
 			return false;
-		xdr_write_pages(xdr, dirlist->pages, 0, dirlist->len);
+		svcxdr_encode_opaque_pages(rqstp, xdr, dirlist->pages, 0,
+					   dirlist->len);
 		/* no more entries */
 		if (xdr_stream_encode_item_absent(xdr) < 0)
 			return false;
diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c
index caf6355b18fa..5777f40c7353 100644
--- a/fs/nfsd/nfsxdr.c
+++ b/fs/nfsd/nfsxdr.c
@@ -468,7 +468,8 @@ nfssvc_encode_readlinkres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 	case nfs_ok:
 		if (xdr_stream_encode_u32(xdr, resp->len) < 0)
 			return false;
-		xdr_write_pages(xdr, &resp->page, 0, resp->len);
+		svcxdr_encode_opaque_pages(rqstp, xdr, &resp->page, 0,
+					   resp->len);
 		if (svc_encode_result_payload(rqstp, head->iov_len, resp->len) < 0)
 			return false;
 		break;
@@ -491,8 +492,9 @@ nfssvc_encode_readres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 			return false;
 		if (xdr_stream_encode_u32(xdr, resp->count) < 0)
 			return false;
-		xdr_write_pages(xdr, resp->pages, rqstp->rq_res.page_base,
-				resp->count);
+		svcxdr_encode_opaque_pages(rqstp, xdr, resp->pages,
+					   rqstp->rq_res.page_base,
+					   resp->count);
 		if (svc_encode_result_payload(rqstp, head->iov_len, resp->count) < 0)
 			return false;
 		break;
@@ -511,7 +513,8 @@ nfssvc_encode_readdirres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 		return false;
 	switch (resp->status) {
 	case nfs_ok:
-		xdr_write_pages(xdr, dirlist->pages, 0, dirlist->len);
+		svcxdr_encode_opaque_pages(rqstp, xdr, dirlist->pages, 0,
+					   dirlist->len);
 		/* no more entries */
 		if (xdr_stream_encode_item_absent(xdr) < 0)
 			return false;
diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index 762d7231e574..3b10636c51a9 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -508,6 +508,27 @@ static inline void svcxdr_init_encode(struct svc_rqst *rqstp)
 	xdr->rqst = NULL;
 }
 
+/**
+ * svcxdr_encode_opaque_pages - Insert pages into an xdr_stream
+ * @xdr: xdr_stream to be updated
+ * @pages: array of pages to insert
+ * @base: starting offset of first data byte in @pages
+ * @len: number of data bytes in @pages to insert
+ *
+ * After the @pages are added, the tail iovec is instantiated pointing
+ * to end of the head buffer, and the stream is set up to encode
+ * subsequent items into the tail.
+ */
+static inline void svcxdr_encode_opaque_pages(struct svc_rqst *rqstp,
+					      struct xdr_stream *xdr,
+					      struct page **pages,
+					      unsigned int base,
+					      unsigned int len)
+{
+	xdr_write_pages(xdr, pages, base, len);
+	xdr->page_ptr = rqstp->rq_next_page - 1;
+}
+
 /**
  * svcxdr_set_auth_slack -
  * @rqstp: RPC transaction
-- 
cgit v1.2.3


From ba21e20b309564c64761f4953db4456ec8c4e49c Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Thu, 18 May 2023 13:45:43 -0400
Subject: NFSD: Use svcxdr_encode_opaque_pages() in nfsd4_encode_splice_read()

Commit 15b23ef5d348 ("nfsd4: fix corruption of NFSv4 read data")
encountered exactly the same issue: after a splice read, a
filesystem-owned page is left in rq_pages[]; the symptoms are the
same as described there.

If the computed number of pages in nfsd4_encode_splice_read() is not
exactly the same as the actual number of pages that were consumed by
nfsd_splice_actor() (say, because of a bug) then hilarity ensues.

Instead of recomputing the page offset based on the size of the
payload, use rq_next_page, which is already properly updated by
nfsd_splice_actor(), to cause svc_rqst_release_pages() to operate
correctly in every instance.

This is a defensive change since we believe that after commit
27c934dd8832 ("nfsd: don't replace page in rq_pages if it's a
continuation of last page") has been applied, there are no known
opportunities for nfsd_splice_actor() to screw up. So I'm not
marking it for stable backport.

Reported-by: Andy Zlotek <andy.zlotek@oracle.com>
Suggested-by: Calum Mackay <calum.mackay@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs4xdr.c | 43 +++++++++++++++++++++----------------------
 1 file changed, 21 insertions(+), 22 deletions(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index c5c6873b938d..b78c2391a2a1 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -4032,6 +4032,11 @@ nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr,
 	return nfsd4_encode_stateid(xdr, &od->od_stateid);
 }
 
+/*
+ * The operation of this function assumes that this is the only
+ * READ operation in the COMPOUND. If there are multiple READs,
+ * we use nfsd4_encode_readv().
+ */
 static __be32 nfsd4_encode_splice_read(
 				struct nfsd4_compoundres *resp,
 				struct nfsd4_read *read,
@@ -4042,8 +4047,12 @@ static __be32 nfsd4_encode_splice_read(
 	int status, space_left;
 	__be32 nfserr;
 
-	/* Make sure there will be room for padding if needed */
-	if (xdr->end - xdr->p < 1)
+	/*
+	 * Make sure there is room at the end of buf->head for
+	 * svcxdr_encode_opaque_pages() to create a tail buffer
+	 * to XDR-pad the payload.
+	 */
+	if (xdr->iov != xdr->buf->head || xdr->end - xdr->p < 1)
 		return nfserr_resource;
 
 	nfserr = nfsd_splice_read(read->rd_rqstp, read->rd_fhp,
@@ -4052,6 +4061,8 @@ static __be32 nfsd4_encode_splice_read(
 	read->rd_length = maxcount;
 	if (nfserr)
 		goto out_err;
+	svcxdr_encode_opaque_pages(read->rd_rqstp, xdr, buf->pages,
+				   buf->page_base, maxcount);
 	status = svc_encode_result_payload(read->rd_rqstp,
 					   buf->head[0].iov_len, maxcount);
 	if (status) {
@@ -4059,31 +4070,19 @@ static __be32 nfsd4_encode_splice_read(
 		goto out_err;
 	}
 
-	buf->page_len = maxcount;
-	buf->len += maxcount;
-	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
-							/ PAGE_SIZE;
-
-	/* Use rest of head for padding and remaining ops: */
-	buf->tail[0].iov_base = xdr->p;
-	buf->tail[0].iov_len = 0;
-	xdr->iov = buf->tail;
-	if (maxcount&3) {
-		int pad = 4 - (maxcount&3);
-
-		*(xdr->p++) = 0;
-
-		buf->tail[0].iov_base += maxcount&3;
-		buf->tail[0].iov_len = pad;
-		buf->len += pad;
-	}
-
+	/*
+	 * Prepare to encode subsequent operations.
+	 *
+	 * xdr_truncate_encode() is not safe to use after a successful
+	 * splice read has been done, so the following stream
+	 * manipulations are open-coded.
+	 */
 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
 				buf->buflen - buf->len);
 	buf->buflen = buf->len + space_left;
 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
 
-	return 0;
+	return nfs_ok;
 
 out_err:
 	/*
-- 
cgit v1.2.3


From ed4a567a179ec15c15f78fa60ca6de9cc4f34897 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Thu, 18 May 2023 13:45:50 -0400
Subject: NFSD: Update rq_next_page between COMPOUND operations

A GETATTR with a large result can advance xdr->page_ptr without
updating rq_next_page. If a splice READ follows that GETATTR in the
COMPOUND, nfsd_splice_actor can start splicing at the wrong page.

I've also seen READLINK and READDIR leave rq_next_page in an
unmodified state.

There are potentially a myriad of combinations like this, so play it
safe: move the rq_next_page update to nfsd4_encode_operation.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs4xdr.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index b78c2391a2a1..3887da048232 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -5438,6 +5438,12 @@ status:
 release:
 	if (opdesc && opdesc->op_release)
 		opdesc->op_release(&op->u);
+
+	/*
+	 * Account for pages consumed while encoding this operation.
+	 * The xdr_stream primitives don't manage rq_next_page.
+	 */
+	rqstp->rq_next_page = xdr->page_ptr + 1;
 }
 
 /* 
@@ -5506,9 +5512,6 @@ nfs4svc_encode_compoundres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 	p = resp->statusp;
 
 	*p++ = resp->cstate.status;
-
-	rqstp->rq_next_page = xdr->page_ptr + 1;
-
 	*p++ = htonl(resp->taglen);
 	memcpy(p, resp->tag, resp->taglen);
 	p += XDR_QUADLEN(resp->taglen);
-- 
cgit v1.2.3


From 507df40ebf31655203dd05e6e31db5849a83347a Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Thu, 18 May 2023 13:45:56 -0400
Subject: NFSD: Hoist rq_vec preparation into nfsd_read()

Accrue the following benefits:

a) Deduplicate this common bit of code.

b) Don't prepare rq_vec for NFSv2 and NFSv3 spliced reads, which
   don't use rq_vec. This is already the case for
   nfsd4_encode_read().

c) Eventually, converting NFSD's read path to use a bvec iterator
   will be simpler.

In the next patch, nfsd_iter_read() will replace nfsd_readv() for
all NFS versions.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs3proc.c | 14 +----------
 fs/nfsd/nfsproc.c  | 14 +----------
 fs/nfsd/vfs.c      | 68 +++++++++++++++++++++++++++++++++++++++++++++++-------
 fs/nfsd/vfs.h      |  8 +++++--
 4 files changed, 68 insertions(+), 36 deletions(-)

diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c
index e6bb8eeb5bc2..fc8d5b7db9f8 100644
--- a/fs/nfsd/nfs3proc.c
+++ b/fs/nfsd/nfs3proc.c
@@ -151,8 +151,6 @@ nfsd3_proc_read(struct svc_rqst *rqstp)
 {
 	struct nfsd3_readargs *argp = rqstp->rq_argp;
 	struct nfsd3_readres *resp = rqstp->rq_resp;
-	unsigned int len;
-	int v;
 
 	dprintk("nfsd: READ(3) %s %lu bytes at %Lu\n",
 				SVCFH_fmt(&argp->fh),
@@ -166,17 +164,7 @@ nfsd3_proc_read(struct svc_rqst *rqstp)
 	if (argp->offset + argp->count > (u64)OFFSET_MAX)
 		argp->count = (u64)OFFSET_MAX - argp->offset;
 
-	v = 0;
-	len = argp->count;
 	resp->pages = rqstp->rq_next_page;
-	while (len > 0) {
-		struct page *page = *(rqstp->rq_next_page++);
-
-		rqstp->rq_vec[v].iov_base = page_address(page);
-		rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE);
-		len -= rqstp->rq_vec[v].iov_len;
-		v++;
-	}
 
 	/* Obtain buffer pointer for payload.
 	 * 1 (status) + 22 (post_op_attr) + 1 (count) + 1 (eof)
@@ -187,7 +175,7 @@ nfsd3_proc_read(struct svc_rqst *rqstp)
 
 	fh_copy(&resp->fh, &argp->fh);
 	resp->status = nfsd_read(rqstp, &resp->fh, argp->offset,
-				 rqstp->rq_vec, v, &resp->count, &resp->eof);
+				 &resp->count, &resp->eof);
 	return rpc_success;
 }
 
diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
index c37195572fd0..a7315928a760 100644
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -176,9 +176,7 @@ nfsd_proc_read(struct svc_rqst *rqstp)
 {
 	struct nfsd_readargs *argp = rqstp->rq_argp;
 	struct nfsd_readres *resp = rqstp->rq_resp;
-	unsigned int len;
 	u32 eof;
-	int v;
 
 	dprintk("nfsd: READ    %s %d bytes at %d\n",
 		SVCFH_fmt(&argp->fh),
@@ -187,17 +185,7 @@ nfsd_proc_read(struct svc_rqst *rqstp)
 	argp->count = min_t(u32, argp->count, NFSSVC_MAXBLKSIZE_V2);
 	argp->count = min_t(u32, argp->count, rqstp->rq_res.buflen);
 
-	v = 0;
-	len = argp->count;
 	resp->pages = rqstp->rq_next_page;
-	while (len > 0) {
-		struct page *page = *(rqstp->rq_next_page++);
-
-		rqstp->rq_vec[v].iov_base = page_address(page);
-		rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE);
-		len -= rqstp->rq_vec[v].iov_len;
-		v++;
-	}
 
 	/* Obtain buffer pointer for payload. 19 is 1 word for
 	 * status, 17 words for fattr, and 1 word for the byte count.
@@ -207,7 +195,7 @@ nfsd_proc_read(struct svc_rqst *rqstp)
 	resp->count = argp->count;
 	fh_copy(&resp->fh, &argp->fh);
 	resp->status = nfsd_read(rqstp, &resp->fh, argp->offset,
-				 rqstp->rq_vec, v, &resp->count, &eof);
+				 &resp->count, &eof);
 	if (resp->status == nfs_ok)
 		resp->status = fh_getattr(&resp->fh, &resp->stat);
 	else if (resp->status == nfserr_jukebox)
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 0016bcc04a59..d9055b5c496b 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1036,6 +1036,50 @@ __be32 nfsd_readv(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	return nfsd_finish_read(rqstp, fhp, file, offset, count, eof, host_err);
 }
 
+/**
+ * nfsd_iter_read - Perform a VFS read using an iterator
+ * @rqstp: RPC transaction context
+ * @fhp: file handle of file to be read
+ * @file: opened struct file of file to be read
+ * @offset: starting byte offset
+ * @count: IN: requested number of bytes; OUT: number of bytes read
+ * @base: offset in first page of read buffer
+ * @eof: OUT: set non-zero if operation reached the end of the file
+ *
+ * Some filesystems or situations cannot use nfsd_splice_read. This
+ * function is the slightly less-performant fallback for those cases.
+ *
+ * Returns nfs_ok on success, otherwise an nfserr stat value is
+ * returned.
+ */
+__be32 nfsd_iter_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
+		      struct file *file, loff_t offset, unsigned long *count,
+		      unsigned int base, u32 *eof)
+{
+	unsigned long v, total;
+	struct iov_iter iter;
+	loff_t ppos = offset;
+	struct page *page;
+	ssize_t host_err;
+
+	v = 0;
+	total = *count;
+	while (total) {
+		page = *(rqstp->rq_next_page++);
+		rqstp->rq_vec[v].iov_base = page_address(page) + base;
+		rqstp->rq_vec[v].iov_len = min_t(size_t, total, PAGE_SIZE - base);
+		total -= rqstp->rq_vec[v].iov_len;
+		++v;
+		base = 0;
+	}
+	WARN_ON_ONCE(v > ARRAY_SIZE(rqstp->rq_vec));
+
+	trace_nfsd_read_vector(rqstp, fhp, offset, *count);
+	iov_iter_kvec(&iter, ITER_DEST, rqstp->rq_vec, v, *count);
+	host_err = vfs_iter_read(file, &iter, &ppos, 0);
+	return nfsd_finish_read(rqstp, fhp, file, offset, count, eof, host_err);
+}
+
 /*
  * Gathered writes: If another process is currently writing to the file,
  * there's a high chance this is another nfsd (triggered by a bulk write
@@ -1161,14 +1205,24 @@ out_nfserr:
 	return nfserr;
 }
 
-/*
- * Read data from a file. count must contain the requested read count
- * on entry. On return, *count contains the number of bytes actually read.
+/**
+ * nfsd_read - Read data from a file
+ * @rqstp: RPC transaction context
+ * @fhp: file handle of file to be read
+ * @offset: starting byte offset
+ * @count: IN: requested number of bytes; OUT: number of bytes read
+ * @eof: OUT: set non-zero if operation reached the end of the file
+ *
+ * The caller must verify that there is enough space in @rqstp.rq_res
+ * to perform this operation.
+ *
  * N.B. After this call fhp needs an fh_put
+ *
+ * Returns nfs_ok on success, otherwise an nfserr stat value is
+ * returned.
  */
 __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
-	loff_t offset, struct kvec *vec, int vlen, unsigned long *count,
-	u32 *eof)
+		 loff_t offset, unsigned long *count, u32 *eof)
 {
 	struct nfsd_file	*nf;
 	struct file *file;
@@ -1183,12 +1237,10 @@ __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if (file->f_op->splice_read && test_bit(RQ_SPLICE_OK, &rqstp->rq_flags))
 		err = nfsd_splice_read(rqstp, fhp, file, offset, count, eof);
 	else
-		err = nfsd_readv(rqstp, fhp, file, offset, vec, vlen, count, eof);
+		err = nfsd_iter_read(rqstp, fhp, file, offset, count, 0, eof);
 
 	nfsd_file_put(nf);
-
 	trace_nfsd_read_done(rqstp, fhp, offset, *count);
-
 	return err;
 }
 
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index 43fb57a301d3..6381a2890b0b 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -115,8 +115,12 @@ __be32		nfsd_readv(struct svc_rqst *rqstp, struct svc_fh *fhp,
 				struct kvec *vec, int vlen,
 				unsigned long *count,
 				u32 *eof);
-__be32 		nfsd_read(struct svc_rqst *, struct svc_fh *,
-				loff_t, struct kvec *, int, unsigned long *,
+__be32		nfsd_iter_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
+				struct file *file, loff_t offset,
+				unsigned long *count, unsigned int base,
+				u32 *eof);
+__be32		nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
+				loff_t offset, unsigned long *count,
 				u32 *eof);
 __be32 		nfsd_write(struct svc_rqst *, struct svc_fh *, loff_t,
 				struct kvec *, int, unsigned long *,
-- 
cgit v1.2.3


From 703d7521555504b3a316b105b4806d641b7ebc76 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Thu, 18 May 2023 13:46:03 -0400
Subject: NFSD: Hoist rq_vec preparation into nfsd_read() [step two]

Now that the preparation of an rq_vec has been removed from the
generic read path, nfsd_splice_read() no longer needs to reset
rq_next_page.

nfsd4_encode_read() calls nfsd_splice_read() directly. As far as I
can ascertain, resetting rq_next_page for NFSv4 splice reads is
unnecessary because rq_next_page is already set correctly.

Moreover, resetting it might even be incorrect if previous
operations in the COMPOUND have already consumed at least a page of
the send buffer. I would expect that the result would be encoding
the READ payload over previously-encoded results.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs4xdr.c          | 10 +++++-----
 fs/nfsd/vfs.c              | 13 ++++++++++++-
 include/linux/sunrpc/xdr.h |  3 +--
 net/sunrpc/xdr.c           | 26 ++++++++++++--------------
 4 files changed, 30 insertions(+), 22 deletions(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 3887da048232..c67bc904c7b7 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -4103,13 +4103,13 @@ static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
 	__be32 zero = xdr_zero;
 	__be32 nfserr;
 
-	read->rd_vlen = xdr_reserve_space_vec(xdr, resp->rqstp->rq_vec, maxcount);
-	if (read->rd_vlen < 0)
+	if (xdr_reserve_space_vec(xdr, maxcount) < 0)
 		return nfserr_resource;
 
-	nfserr = nfsd_readv(resp->rqstp, read->rd_fhp, file, read->rd_offset,
-			    resp->rqstp->rq_vec, read->rd_vlen, &maxcount,
-			    &read->rd_eof);
+	nfserr = nfsd_iter_read(resp->rqstp, read->rd_fhp, file,
+				read->rd_offset, &maxcount,
+				xdr->buf->page_len & ~PAGE_MASK,
+				&read->rd_eof);
 	read->rd_length = maxcount;
 	if (nfserr)
 		return nfserr;
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index d9055b5c496b..37febe1ff039 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1003,6 +1003,18 @@ static __be32 nfsd_finish_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	}
 }
 
+/**
+ * nfsd_splice_read - Perform a VFS read using a splice pipe
+ * @rqstp: RPC transaction context
+ * @fhp: file handle of file to be read
+ * @file: opened struct file of file to be read
+ * @offset: starting byte offset
+ * @count: IN: requested number of bytes; OUT: number of bytes read
+ * @eof: OUT: set non-zero if operation reached the end of the file
+ *
+ * Returns nfs_ok on success, otherwise an nfserr stat value is
+ * returned.
+ */
 __be32 nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
 			struct file *file, loff_t offset, unsigned long *count,
 			u32 *eof)
@@ -1016,7 +1028,6 @@ __be32 nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	ssize_t host_err;
 
 	trace_nfsd_read_splice(rqstp, fhp, offset, *count);
-	rqstp->rq_next_page = rqstp->rq_respages + 1;
 	host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor);
 	return nfsd_finish_read(rqstp, fhp, file, offset, count, eof, host_err);
 }
diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 72014c9216fc..f89ec4b5ea16 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -242,8 +242,7 @@ extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf,
 extern void xdr_init_encode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
 			   struct page **pages, struct rpc_rqst *rqst);
 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
-extern int xdr_reserve_space_vec(struct xdr_stream *xdr, struct kvec *vec,
-		size_t nbytes);
+extern int xdr_reserve_space_vec(struct xdr_stream *xdr, size_t nbytes);
 extern void __xdr_commit_encode(struct xdr_stream *xdr);
 extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len);
 extern void xdr_truncate_decode(struct xdr_stream *xdr, size_t len);
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 36835b2f5446..2a22e78af116 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -1070,22 +1070,22 @@ __be32 * xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes)
 }
 EXPORT_SYMBOL_GPL(xdr_reserve_space);
 
-
 /**
  * xdr_reserve_space_vec - Reserves a large amount of buffer space for sending
  * @xdr: pointer to xdr_stream
- * @vec: pointer to a kvec array
  * @nbytes: number of bytes to reserve
  *
- * Reserves enough buffer space to encode 'nbytes' of data and stores the
- * pointers in 've