From 1983a66f575bed05ef63a15193246758055c50b2 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@redhat.com>
Date: Thu, 11 Aug 2016 13:36:22 -0400
Subject: nfsd: don't set a FL_LAYOUT lease for flexfiles layouts

We currently can hit a deadlock (of sorts) when trying to use flexfiles
layouts with XFS. XFS will call break_layout when something wants to
write to the file. In the case of the (super-simple) flexfiles layout
driver in knfsd, the MDS and DS are the same machine.

The client can get a layout and then issue a v3 write to do its I/O. XFS
will then call xfs_break_layouts, which will cause a CB_LAYOUTRECALL to
be issued to the client. The client however can't return the layout
until the v3 WRITE completes, but XFS won't allow the write to proceed
until the layout is returned.

Christoph says:

    XFS only cares about block-like layouts where the client has direct
    access to the file blocks.  I'd need to look how to propagate the
    flag into break_layout, but in principle we don't need to do any
    recalls on truncate ever for file and flexfile layouts.

If we're never going to recall the layout, then we don't even need to
set the lease at all. Just skip doing so on flexfiles layouts by
adding a new flag to struct nfsd4_layout_ops and skipping the lease
setting and removal when that flag is true.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/flexfilelayout.c | 1 +
 fs/nfsd/nfs4layouts.c    | 6 +++++-
 fs/nfsd/pnfs.h           | 1 +
 3 files changed, 7 insertions(+), 1 deletion(-)

(limited to 'fs')

diff --git a/fs/nfsd/flexfilelayout.c b/fs/nfsd/flexfilelayout.c
index df880e9fa71f..b67287383010 100644
--- a/fs/nfsd/flexfilelayout.c
+++ b/fs/nfsd/flexfilelayout.c
@@ -126,6 +126,7 @@ nfsd4_ff_proc_getdeviceinfo(struct super_block *sb, struct svc_rqst *rqstp,
 const struct nfsd4_layout_ops ff_layout_ops = {
 	.notify_types		=
 			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
+	.disable_recalls	= true,
 	.proc_getdeviceinfo	= nfsd4_ff_proc_getdeviceinfo,
 	.encode_getdeviceinfo	= nfsd4_ff_encode_getdeviceinfo,
 	.proc_layoutget		= nfsd4_ff_proc_layoutget,
diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c
index 2be9602b0221..42aace4fc4c8 100644
--- a/fs/nfsd/nfs4layouts.c
+++ b/fs/nfsd/nfs4layouts.c
@@ -174,7 +174,8 @@ nfsd4_free_layout_stateid(struct nfs4_stid *stid)
 	list_del_init(&ls->ls_perfile);
 	spin_unlock(&fp->fi_lock);
 
-	vfs_setlease(ls->ls_file, F_UNLCK, NULL, (void **)&ls);
+	if (!nfsd4_layout_ops[ls->ls_layout_type]->disable_recalls)
+		vfs_setlease(ls->ls_file, F_UNLCK, NULL, (void **)&ls);
 	fput(ls->ls_file);
 
 	if (ls->ls_recalled)
@@ -189,6 +190,9 @@ nfsd4_layout_setlease(struct nfs4_layout_stateid *ls)
 	struct file_lock *fl;
 	int status;
 
+	if (nfsd4_layout_ops[ls->ls_layout_type]->disable_recalls)
+		return 0;
+
 	fl = locks_alloc_lock();
 	if (!fl)
 		return -ENOMEM;
diff --git a/fs/nfsd/pnfs.h b/fs/nfsd/pnfs.h
index 0c2a716e8741..d27a5aa60022 100644
--- a/fs/nfsd/pnfs.h
+++ b/fs/nfsd/pnfs.h
@@ -19,6 +19,7 @@ struct nfsd4_deviceid_map {
 
 struct nfsd4_layout_ops {
 	u32		notify_types;
+	bool		disable_recalls;
 
 	__be32 (*proc_getdeviceinfo)(struct super_block *sb,
 			struct svc_rqst *rqstp,
-- 
cgit v1.2.3


From 89dfdc964bb4b2112c2cd058412f49d9906c9d35 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@redhat.com>
Date: Tue, 16 Aug 2016 13:29:27 -0400
Subject: nfsd: eliminate cb_minorversion field

We already have that info in the client pointer. No need to pass around
a copy.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4callback.c | 7 +++----
 fs/nfsd/state.h        | 1 -
 2 files changed, 3 insertions(+), 5 deletions(-)

(limited to 'fs')

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 04c68d900324..dbef646c6a2d 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -448,7 +448,7 @@ static int decode_cb_sequence4res(struct xdr_stream *xdr,
 {
 	int status;
 
-	if (cb->cb_minorversion == 0)
+	if (cb->cb_clp->cl_minorversion == 0)
 		return 0;
 
 	status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_seq_status);
@@ -485,7 +485,7 @@ static void nfs4_xdr_enc_cb_recall(struct rpc_rqst *req, struct xdr_stream *xdr,
 	const struct nfs4_delegation *dp = cb_to_delegation(cb);
 	struct nfs4_cb_compound_hdr hdr = {
 		.ident = cb->cb_clp->cl_cb_ident,
-		.minorversion = cb->cb_minorversion,
+		.minorversion = cb->cb_clp->cl_minorversion,
 	};
 
 	encode_cb_compound4args(xdr, &hdr);
@@ -594,7 +594,7 @@ static void nfs4_xdr_enc_cb_layout(struct rpc_rqst *req,
 		container_of(cb, struct nfs4_layout_stateid, ls_recall);
 	struct nfs4_cb_compound_hdr hdr = {
 		.ident = 0,
-		.minorversion = cb->cb_minorversion,
+		.minorversion = cb->cb_clp->cl_minorversion,
 	};
 
 	encode_cb_compound4args(xdr, &hdr);
@@ -862,7 +862,6 @@ static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata)
 	struct nfs4_client *clp = cb->cb_clp;
 	u32 minorversion = clp->cl_minorversion;
 
-	cb->cb_minorversion = minorversion;
 	/*
 	 * cb_seq_status is only set in decode_cb_sequence4res,
 	 * and so will remain 1 if an rpc level failure occurs.
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index b95adf9a1595..0bdc79cb359c 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -63,7 +63,6 @@ typedef struct {
 
 struct nfsd4_callback {
 	struct nfs4_client *cb_clp;
-	u32 cb_minorversion;
 	struct rpc_message cb_msg;
 	const struct nfsd4_callback_ops *cb_ops;
 	struct work_struct cb_work;
-- 
cgit v1.2.3


From bec782b4fccd395bacb6f99187a9131f7826cbd1 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@redhat.com>
Date: Thu, 22 Sep 2016 07:19:02 -0400
Subject: nfsd: fix dprintk in nfsd4_encode_getdeviceinfo

nfserr is big-endian, so we should convert it to host-endian before
printing it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4xdr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'fs')

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 0aa0236a1429..7f8232e32dc7 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -4062,7 +4062,7 @@ nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
 	u32 starting_len = xdr->buf->len, needed_len;
 	__be32 *p;
 
-	dprintk("%s: err %d\n", __func__, nfserr);
+	dprintk("%s: err %d\n", __func__, be32_to_cpu(nfserr));
 	if (nfserr)
 		goto out;
 
-- 
cgit v1.2.3


From 1eca45f8a840987d0df355e0176921653e4f7ec2 Mon Sep 17 00:00:00 2001
From: Vasily Averin <vvs@virtuozzo.com>
Date: Wed, 21 Sep 2016 15:33:05 +0300
Subject: NFSD: fix corruption in notifier registration

By design notifier can be registered once only, however nfsd registers
the same inetaddr notifiers per net-namespace.  When this happen it
corrupts list of notifiers, as result some notifiers can be not called
on proper event, traverse on list can be cycled forever, and second
unregister can access already freed memory.

Cc: stable@vger.kernel.org
fixes: 36684996 ("nfsd: Register callbacks on the inetaddr_chain and inet6addr_chain")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfssvc.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

(limited to 'fs')

diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 45007acaf364..a2b65fc56dd6 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -366,14 +366,21 @@ static struct notifier_block nfsd_inet6addr_notifier = {
 };
 #endif
 
+/* Only used under nfsd_mutex, so this atomic may be overkill: */
+static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0);
+
 static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
 {
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 
-	unregister_inetaddr_notifier(&nfsd_inetaddr_notifier);
+	/* check if the notifier still has clients */
+	if (atomic_dec_return(&nfsd_notifier_refcount) == 0) {
+		unregister_inetaddr_notifier(&nfsd_inetaddr_notifier);
 #if IS_ENABLED(CONFIG_IPV6)
-	unregister_inet6addr_notifier(&nfsd_inet6addr_notifier);
+		unregister_inet6addr_notifier(&nfsd_inet6addr_notifier);
 #endif
+	}
+
 	/*
 	 * write_ports can create the server without actually starting
 	 * any threads--if we get shut down before any threads are
@@ -488,10 +495,13 @@ int nfsd_create_serv(struct net *net)
 	}
 
 	set_max_drc();
-	register_inetaddr_notifier(&nfsd_inetaddr_notifier);
+	/* check if the notifier is already set */
+	if (atomic_inc_return(&nfsd_notifier_refcount) == 1) {
+		register_inetaddr_notifier(&nfsd_inetaddr_notifier);
 #if IS_ENABLED(CONFIG_IPV6)
-	register_inet6addr_notifier(&nfsd_inet6addr_notifier);
+		register_inet6addr_notifier(&nfsd_inet6addr_notifier);
 #endif
+	}
 	do_gettimeofday(&nn->nfssvc_boot);		/* record boot time */
 	return 0;
 }
-- 
cgit v1.2.3


From a188620ebd294b18d8da93f4b2a307d484e7bd27 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@redhat.com>
Date: Fri, 16 Sep 2016 16:28:23 -0400
Subject: nfsd: plumb in a CB_NOTIFY_LOCK operation

Add the encoding/decoding for CB_NOTIFY_LOCK operations.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4callback.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++
 fs/nfsd/state.h        |  7 +++++++
 fs/nfsd/xdr4cb.h       |  9 ++++++++
 3 files changed, 73 insertions(+)

(limited to 'fs')

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index dbef646c6a2d..211dc2aed8e1 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -623,6 +623,62 @@ static int nfs4_xdr_dec_cb_layout(struct rpc_rqst *rqstp,
 }
 #endif /* CONFIG_NFSD_PNFS */
 
+static void encode_stateowner(struct xdr_stream *xdr, struct nfs4_stateowner *so)
+{
+	__be32	*p;
+
+	p = xdr_reserve_space(xdr, 8 + 4 + so->so_owner.len);
+	p = xdr_encode_opaque_fixed(p, &so->so_client->cl_clientid, 8);
+	xdr_encode_opaque(p, so->so_owner.data, so->so_owner.len);
+}
+
+static void nfs4_xdr_enc_cb_notify_lock(struct rpc_rqst *req,
+					struct xdr_stream *xdr,
+					const struct nfsd4_callback *cb)
+{
+	const struct nfsd4_blocked_lock *nbl =
+		container_of(cb, struct nfsd4_blocked_lock, nbl_cb);
+	struct nfs4_lockowner *lo = (struct nfs4_lockowner *)nbl->nbl_lock.fl_owner;
+	struct nfs4_cb_compound_hdr hdr = {
+		.ident = 0,
+		.minorversion = cb->cb_clp->cl_minorversion,
+	};
+
+	__be32 *p;
+
+	BUG_ON(hdr.minorversion == 0);
+
+	encode_cb_compound4args(xdr, &hdr);
+	encode_cb_sequence4args(xdr, cb, &hdr);
+
+	p = xdr_reserve_space(xdr, 4);
+	*p = cpu_to_be32(OP_CB_NOTIFY_LOCK);
+	encode_nfs_fh4(xdr, &nbl->nbl_fh);
+	encode_stateowner(xdr, &lo->lo_owner);
+	hdr.nops++;
+
+	encode_cb_nops(&hdr);
+}
+
+static int nfs4_xdr_dec_cb_notify_lock(struct rpc_rqst *rqstp,
+					struct xdr_stream *xdr,
+					struct nfsd4_callback *cb)
+{
+	struct nfs4_cb_compound_hdr hdr;
+	int status;
+
+	status = decode_cb_compound4res(xdr, &hdr);
+	if (unlikely(status))
+		return status;
+
+	if (cb) {
+		status = decode_cb_sequence4res(xdr, cb);
+		if (unlikely(status || cb->cb_seq_status))
+			return status;
+	}
+	return decode_cb_op_status(xdr, OP_CB_NOTIFY_LOCK, &cb->cb_status);
+}
+
 /*
  * RPC procedure tables
  */
@@ -643,6 +699,7 @@ static struct rpc_procinfo nfs4_cb_procedures[] = {
 #ifdef CONFIG_NFSD_PNFS
 	PROC(CB_LAYOUT,	COMPOUND,	cb_layout,	cb_layout),
 #endif
+	PROC(CB_NOTIFY_LOCK,	COMPOUND,	cb_notify_lock,	cb_notify_lock),
 };
 
 static struct rpc_version nfs_cb_version4 = {
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 0bdc79cb359c..88d029dd13aa 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -571,6 +571,7 @@ enum nfsd4_cb_op {
 	NFSPROC4_CLNT_CB_RECALL,
 	NFSPROC4_CLNT_CB_LAYOUT,
 	NFSPROC4_CLNT_CB_SEQUENCE,
+	NFSPROC4_CLNT_CB_NOTIFY_LOCK,
 };
 
 /* Returns true iff a is later than b: */
@@ -579,6 +580,12 @@ static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b)
 	return (s32)(a->si_generation - b->si_generation) > 0;
 }
 
+struct nfsd4_blocked_lock {
+	struct file_lock	nbl_lock;
+	struct knfsd_fh		nbl_fh;
+	struct nfsd4_callback	nbl_cb;
+};
+
 struct nfsd4_compound_state;
 struct nfsd_net;
 
diff --git a/fs/nfsd/xdr4cb.h b/fs/nfsd/xdr4cb.h
index c47f6fdb111a..49b719dfef95 100644
--- a/fs/nfsd/xdr4cb.h
+++ b/fs/nfsd/xdr4cb.h
@@ -28,3 +28,12 @@
 #define NFS4_dec_cb_layout_sz		(cb_compound_dec_hdr_sz  +      \
 					cb_sequence_dec_sz +            \
 					op_dec_sz)
+
+#define NFS4_enc_cb_notify_lock_sz	(cb_compound_enc_hdr_sz +        \
+					cb_sequence_enc_sz +             \
+					2 + 1 +				 \
+					XDR_QUADLEN(NFS4_OPAQUE_LIMIT) + \
+					enc_nfs4_fh_sz)
+#define NFS4_dec_cb_notify_lock_sz	(cb_compound_dec_hdr_sz  +      \
+					cb_sequence_dec_sz +            \
+					op_dec_sz)
-- 
cgit v1.2.3


From 76d348fadff52e8ad10e7f587a4560df79a5fefe Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@redhat.com>
Date: Fri, 16 Sep 2016 16:28:24 -0400
Subject: nfsd: have nfsd4_lock use blocking locks for v4.1+ locks

Create a new per-lockowner+per-inode structure that contains a
file_lock. Have nfsd4_lock add this structure to the lockowner's list
prior to setting the lock. Then call the vfs and request a blocking lock
(by setting FL_SLEEP). If we get anything besides FILE_LOCK_DEFERRED
back, then we dequeue the block structure and free it. When the next
lock request comes in, we'll look for an existing block for the same
filehandle and dequeue and reuse it if there is one.

When the lock comes free (a'la an lm_notify call), we dequeue it
from the lockowner's list and kick off a CB_NOTIFY_LOCK callback to
inform the client that it should retry the lock request.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4state.c | 164 ++++++++++++++++++++++++++++++++++++++++++++++------
 fs/nfsd/state.h     |  12 +++-
 2 files changed, 156 insertions(+), 20 deletions(-)

(limited to 'fs')

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index a204d7e109d4..ca0db4974e5b 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -99,6 +99,7 @@ static struct kmem_cache *odstate_slab;
 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 bool is_session_dead(struct nfsd4_session *ses)
 {
@@ -210,6 +211,84 @@ static void nfsd4_put_session(struct nfsd4_session *ses)
 	spin_unlock(&nn->client_lock);
 }
 
+static struct nfsd4_blocked_lock *
+find_blocked_lock(struct nfs4_lockowner *lo, struct knfsd_fh *fh,
+			struct nfsd_net *nn)
+{
+	struct nfsd4_blocked_lock *cur, *found = NULL;
+
+	spin_lock(&nn->client_lock);
+	list_for_each_entry(cur, &lo->lo_blocked, nbl_list) {
+		if (fh_match(fh, &cur->nbl_fh)) {
+			list_del_init(&cur->nbl_list);
+			found = cur;
+			break;
+		}
+	}
+	spin_unlock(&nn->client_lock);
+	if (found)
+		posix_unblock_lock(&found->nbl_lock);
+	return found;
+}
+
+static struct nfsd4_blocked_lock *
+find_or_allocate_block(struct nfs4_lockowner *lo, struct knfsd_fh *fh,
+			struct nfsd_net *nn)
+{
+	struct nfsd4_blocked_lock *nbl;
+
+	nbl = find_blocked_lock(lo, fh, nn);
+	if (!nbl) {
+		nbl= kmalloc(sizeof(*nbl), GFP_KERNEL);
+		if (nbl) {
+			fh_copy_shallow(&nbl->nbl_fh, fh);
+			locks_init_lock(&nbl->nbl_lock);
+			nfsd4_init_cb(&nbl->nbl_cb, lo->lo_owner.so_client,
+					&nfsd4_cb_notify_lock_ops,
+					NFSPROC4_CLNT_CB_NOTIFY_LOCK);
+		}
+	}
+	return nbl;
+}
+
+static void
+free_blocked_lock(struct nfsd4_blocked_lock *nbl)
+{
+	locks_release_private(&nbl->nbl_lock);
+	kfree(nbl);
+}
+
+static int
+nfsd4_cb_notify_lock_done(struct nfsd4_callback *cb, struct rpc_task *task)
+{
+	/*
+	 * Since this is just an optimization, we don't try very hard if it
+	 * turns out not to succeed. We'll requeue it on NFS4ERR_DELAY, and
+	 * just quit trying on anything else.
+	 */
+	switch (task->tk_status) {
+	case -NFS4ERR_DELAY:
+		rpc_delay(task, 1 * HZ);
+		return 0;
+	default:
+		return 1;
+	}
+}
+
+static void
+nfsd4_cb_notify_lock_release(struct nfsd4_callback *cb)
+{
+	struct nfsd4_blocked_lock	*nbl = container_of(cb,
+						struct nfsd4_blocked_lock, nbl_cb);
+
+	free_blocked_lock(nbl);
+}
+
+static const struct nfsd4_callback_ops nfsd4_cb_notify_lock_ops = {
+	.done		= nfsd4_cb_notify_lock_done,
+	.release	= nfsd4_cb_notify_lock_release,
+};
+
 static inline struct nfs4_stateowner *
 nfs4_get_stateowner(struct nfs4_stateowner *sop)
 {
@@ -5309,7 +5388,29 @@ nfsd4_fl_put_owner(fl_owner_t owner)
 		nfs4_put_stateowner(&lo->lo_owner);
 }
 
+static void
+nfsd4_lm_notify(struct file_lock *fl)
+{
+	struct nfs4_lockowner		*lo = (struct nfs4_lockowner *)fl->fl_owner;
+	struct net			*net = lo->lo_owner.so_client->net;
+	struct nfsd_net			*nn = net_generic(net, nfsd_net_id);
+	struct nfsd4_blocked_lock	*nbl = container_of(fl,
+						struct nfsd4_blocked_lock, nbl_lock);
+	bool queue = false;
+
+	spin_lock(&nn->client_lock);
+	if (!list_empty(&nbl->nbl_list)) {
+		list_del_init(&nbl->nbl_list);
+		queue = true;
+	}
+	spin_unlock(&nn->client_lock);
+
+	if (queue)
+		nfsd4_run_cb(&nbl->nbl_cb);
+}
+
 static const struct lock_manager_operations nfsd_posix_mng_ops  = {
+	.lm_notify = nfsd4_lm_notify,
 	.lm_get_owner = nfsd4_fl_get_owner,
 	.lm_put_owner = nfsd4_fl_put_owner,
 };
@@ -5407,6 +5508,7 @@ alloc_init_lock_stateowner(unsigned int strhashval, struct nfs4_client *clp,
 	lo = alloc_stateowner(lockowner_slab, &lock->lk_new_owner, clp);
 	if (!lo)
 		return NULL;
+	INIT_LIST_HEAD(&lo->lo_blocked);
 	INIT_LIST_HEAD(&lo->lo_owner.so_stateids);
 	lo->lo_owner.so_is_open_owner = 0;
 	lo->lo_owner.so_seqid = lock->lk_new_lock_seqid;
@@ -5588,12 +5690,15 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	struct nfs4_ol_stateid *open_stp = NULL;
 	struct nfs4_file *fp;
 	struct file *filp = NULL;
+	struct nfsd4_blocked_lock *nbl = NULL;
 	struct file_lock *file_lock = NULL;
 	struct file_lock *conflock = NULL;
 	__be32 status = 0;
 	int lkflg;
 	int err;
 	bool new = false;
+	unsigned char fl_type;
+	unsigned int fl_flags = FL_POSIX;
 	struct net *net = SVC_NET(rqstp);
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 
@@ -5658,46 +5763,55 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	if (!locks_in_grace(net) && lock->lk_reclaim)
 		goto out;
 
-	file_lock = locks_alloc_lock();
-	if (!file_lock) {
-		dprintk("NFSD: %s: unable to allocate lock!\n", __func__);
-		status = nfserr_jukebox;
-		goto out;
-	}
-
 	fp = lock_stp->st_stid.sc_file;
 	switch (lock->lk_type) {
-		case NFS4_READ_LT:
 		case NFS4_READW_LT:
+			if (nfsd4_has_session(cstate))
+				fl_flags |= FL_SLEEP;
+			/* Fallthrough */
+		case NFS4_READ_LT:
 			spin_lock(&fp->fi_lock);
 			filp = find_readable_file_locked(fp);
 			if (filp)
 				get_lock_access(lock_stp, NFS4_SHARE_ACCESS_READ);
 			spin_unlock(&fp->fi_lock);
-			file_lock->fl_type = F_RDLCK;
+			fl_type = F_RDLCK;
 			break;
-		case NFS4_WRITE_LT:
 		case NFS4_WRITEW_LT:
+			if (nfsd4_has_session(cstate))
+				fl_flags |= FL_SLEEP;
+			/* Fallthrough */
+		case NFS4_WRITE_LT:
 			spin_lock(&fp->fi_lock);
 			filp = find_writeable_file_locked(fp);
 			if (filp)
 				get_lock_access(lock_stp, NFS4_SHARE_ACCESS_WRITE);
 			spin_unlock(&fp->fi_lock);
-			file_lock->fl_type = F_WRLCK;
+			fl_type = F_WRLCK;
 			break;
 		default:
 			status = nfserr_inval;
 		goto out;
 	}
+
 	if (!filp) {
 		status = nfserr_openmode;
 		goto out;
 	}
 
+	nbl = find_or_allocate_block(lock_sop, &fp->fi_fhandle, nn);
+	if (!nbl) {
+		dprintk("NFSD: %s: unable to allocate block!\n", __func__);
+		status = nfserr_jukebox;
+		goto out;
+	}
+
+	file_lock = &nbl->nbl_lock;
+	file_lock->fl_type = fl_type;
 	file_lock->fl_owner = (fl_owner_t)lockowner(nfs4_get_stateowner(&lock_sop->lo_owner));
 	file_lock->fl_pid = current->tgid;
 	file_lock->fl_file = filp;
-	file_lock->fl_flags = FL_POSIX;
+	file_lock->fl_flags = fl_flags;
 	file_lock->fl_lmops = &nfsd_posix_mng_ops;
 	file_lock->fl_start = lock->lk_offset;
 	file_lock->fl_end = last_byte_offset(lock->lk_offset, lock->lk_length);
@@ -5710,18 +5824,27 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 		goto out;
 	}
 
+	if (fl_flags & FL_SLEEP) {
+		spin_lock(&nn->client_lock);
+		list_add_tail(&nbl->nbl_list, &lock_sop->lo_blocked);
+		spin_unlock(&nn->client_lock);
+	}
+
 	err = vfs_lock_file(filp, F_SETLK, file_lock, conflock);
-	switch (-err) {
+	switch (err) {
 	case 0: /* success! */
 		nfs4_inc_and_copy_stateid(&lock->lk_resp_stateid, &lock_stp->st_stid);
 		status = 0;
 		break;
-	case (EAGAIN):		/* conflock holds conflicting lock */
+	case FILE_LOCK_DEFERRED:
+		nbl = NULL;
+		/* Fallthrough */
+	case -EAGAIN:		/* conflock holds conflicting lock */
 		status = nfserr_denied;
 		dprintk("NFSD: nfsd4_lock: conflicting lock found!\n");
 		nfs4_set_lock_denied(conflock, &lock->lk_denied);
 		break;
-	case (EDEADLK):
+	case -EDEADLK:
 		status = nfserr_deadlock;
 		break;
 	default:
@@ -5730,6 +5853,15 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 		break;
 	}
 out:
+	if (nbl) {
+		/* dequeue it if we queued it before */
+		if (fl_flags & FL_SLEEP) {
+			spin_lock(&nn->client_lock);
+			list_del_init(&nbl->nbl_list);
+			spin_unlock(&nn->client_lock);
+		}
+		free_blocked_lock(nbl);
+	}
 	if (filp)
 		fput(filp);
 	if (lock_stp) {
@@ -5753,8 +5885,6 @@ out:
 	if (open_stp)
 		nfs4_put_stid(&open_stp->st_stid);
 	nfsd4_bump_seqid(cstate, status);
-	if (file_lock)
-		locks_free_lock(file_lock);
 	if (conflock)
 		locks_free_lock(conflock);
 	return status;
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 88d029dd13aa..e45c183a8bf7 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -440,11 +440,11 @@ struct nfs4_openowner {
 /*
  * Represents a generic "lockowner". Similar to an openowner. References to it
  * are held by the lock stateids that are created on its behalf. This object is
- * a superset of the nfs4_stateowner struct (or would be if it needed any extra
- * fields).
+ * a superset of the nfs4_stateowner struct.
  */
 struct nfs4_lockowner {
-	struct nfs4_stateowner	lo_owner; /* must be first element */
+	struct nfs4_stateowner	lo_owner;	/* must be first element */
+	struct list_head	lo_blocked;	/* blocked file_locks */
 };
 
 static inline struct nfs4_openowner * openowner(struct nfs4_stateowner *so)
@@ -580,7 +580,13 @@ static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b)
 	return (s32)(a->si_generation - b->si_generation) > 0;
 }
 
+/*
+ * When a client tries to get a lock on a file, we set one of these objects
+ * on the blocking lock. When the lock becomes free, we can then issue a
+ * CB_NOTIFY_LOCK to the server.
+ */
 struct nfsd4_blocked_lock {
+	struct list_head	nbl_list;
 	struct file_lock	nbl_lock;
 	struct knfsd_fh		nbl_fh;
 	struct nfsd4_callback	nbl_cb;
-- 
cgit v1.2.3


From 7919d0a27f1e7cb324e023776aa1cbff00f1ee7b Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@redhat.com>
Date: Fri, 16 Sep 2016 16:28:25 -0400
Subject: nfsd: add a LRU list for blocked locks

It's possible for a client to call in on a lock that is blocked for a
long time, but discontinue polling for it. A malicious client could
even set a lock on a file, and then spam the server with failing lock
requests from different lockowners that pile up in a DoS attack.

Add the blocked lock structures to a per-net namespace LRU when hashing
them, and timestamp them. If the lock request is not revisited after a
lease period, we'll drop it under the assumption that the client is no
longer interested.

This also gives us a mechanism to clean up these objects at server
shutdown time as well.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/netns.h     |  1 +
 fs/nfsd/nfs4state.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 fs/nfsd/state.h     |  2 ++
 3 files changed, 65 insertions(+)

(limited to 'fs')

diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h
index 5fbf3bbd00d0..b10d557f9c9e 100644
--- a/fs/nfsd/netns.h
+++ b/fs/nfsd/netns.h
@@ -84,6 +84,7 @@ struct nfsd_net {
 	struct list_head client_lru;
 	struct list_head close_lru;
 	struct list_head del_recall_lru;
+	struct list_head blocked_locks_lru;
 
 	struct delayed_work laundromat_work;
 
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index ca0db4974e5b..6c74d9a45163 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -221,6 +221,7 @@ find_blocked_lock(struct nfs4_lockowner *lo, struct knfsd_fh *fh,
 	list_for_each_entry(cur, &lo->lo_blocked, nbl_list) {
 		if (fh_match(fh, &cur->nbl_fh)) {
 			list_del_init(&cur->nbl_list);
+			list_del_init(&cur->nbl_lru);
 			found = cur;
 			break;
 		}
@@ -4580,6 +4581,7 @@ nfs4_laundromat(struct nfsd_net *nn)
 	struct nfs4_openowner *oo;
 	struct nfs4_delegation *dp;
 	struct nfs4_ol_stateid *stp;
+	struct nfsd4_blocked_lock *nbl;
 	struct list_head *pos, *next, reaplist;
 	time_t cutoff = get_seconds() - nn->nfsd4_lease;
 	time_t t, new_timeo = nn->nfsd4_lease;
@@ -4648,6 +4650,41 @@ nfs4_laundromat(struct nfsd_net *nn)
 	}
 	spin_unlock(&nn->client_lock);
 
+	/*
+	 * It's possible for a client to try and acquire an already held lock
+	 * that is being held for a long time, and then lose interest in it.
+	 * So, we clean out any un-revisited request after a lease period
+	 * under the assumption that the client is no longer interested.
+	 *
+	 * RFC5661, sec. 9.6 states that the client must not rely on getting
+	 * notifications and must continue to poll for locks, even when the
+	 * server supports them. Thus this shouldn't lead to clients blocking
+	 * indefinitely once the lock does become free.
+	 */
+	BUG_ON(!list_empty(&reaplist));
+	spin_lock(&nn->client_lock);
+	while (!list_empty(&nn->blocked_locks_lru)) {
+		nbl = list_first_entry(&nn->blocked_locks_lru,
+					struct nfsd4_blocked_lock, nbl_lru);
+		if (time_after((unsigned long)nbl->nbl_time,
+			       (unsigned long)cutoff)) {
+			t = nbl->nbl_time - cutoff;
+			new_timeo = min(new_timeo, t);
+			break;
+		}
+		list_move(&nbl->nbl_lru, &reaplist);
+		list_del_init(&nbl->nbl_list);
+	}
+	spin_unlock(&nn->client_lock);
+
+	while (!list_empty(&reaplist)) {
+		nbl = list_first_entry(&nn->blocked_locks_lru,
+					struct nfsd4_blocked_lock, nbl_lru);
+		list_del_init(&nbl->nbl_lru);
+		posix_unblock_lock(&nbl->nbl_lock);
+		free_blocked_lock(nbl);
+	}
+
 	new_timeo = max_t(time_t, new_timeo, NFSD_LAUNDROMAT_MINTIMEOUT);
 	return new_timeo;
 }
@@ -5398,9 +5435,11 @@ nfsd4_lm_notify(struct file_lock *fl)
 						struct nfsd4_blocked_lock, nbl_lock);
 	bool queue = false;
 
+	/* An empty list means that something else is going to be using it */
 	spin_lock(&nn->client_lock);
 	if (!list_empty(&nbl->nbl_list)) {
 		list_del_init(&nbl->nbl_list);
+		list_del_init(&nbl->nbl_lru);
 		queue = true;
 	}
 	spin_unlock(&nn->client_lock);
@@ -5825,8 +5864,10 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	}
 
 	if (fl_flags & FL_SLEEP) {
+		nbl->nbl_time = jiffies;
 		spin_lock(&nn->client_lock);
 		list_add_tail(&nbl->nbl_list, &lock_sop->lo_blocked);
+		list_add_tail(&nbl->nbl_lru, &nn->blocked_locks_lru);
 		spin_unlock(&nn->client_lock);
 	}
 
@@ -5858,6 +5899,7 @@ out:
 		if (fl_flags & FL_SLEEP) {
 			spin_lock(&nn->client_lock);
 			list_del_init(&nbl->nbl_list);
+			list_del_init(&nbl->nbl_lru);
 			spin_unlock(&nn->client_lock);
 		}
 		free_blocked_lock(nbl);
@@ -6898,6 +6940,7 @@ static int nfs4_state_create_net(struct net *net)
 	INIT_LIST_HEAD(&nn->client_lru);
 	INIT_LIST_HEAD(&nn->close_lru);
 	INIT_LIST_HEAD(&nn->del_recall_lru);
+	INIT_LIST_HEAD(&nn->blocked_locks_lru);
 	spin_lock_init(&nn->client_lock);
 
 	INIT_DELAYED_WORK(&nn->laundromat_work, laundromat_main);
@@ -6995,6 +7038,7 @@ nfs4_state_shutdown_net(struct net *net)
 	struct nfs4_delegation *dp = NULL;
 	struct list_head *pos, *next, reaplist;
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+	struct nfsd4_blocked_lock *nbl;
 
 	cancel_delayed_work_sync(&nn->laundromat_work);
 	locks_end_grace(&nn->nfsd4_manager);
@@ -7015,6 +7059,24 @@ nfs4_state_shutdown_net(struct net *net)
 		nfs4_put_stid(&dp->dl_stid);
 	}
 
+	BUG_ON(!list_empty(&reaplist));
+	spin_lock(&nn->client_lock);
+	while (!list_empty(&nn->blocked_locks_lru)) {
+		nbl = list_first_entry(&nn->blocked_locks_lru,
+					struct nfsd4_blocked_lock, nbl_lru);
+		list_move(&nbl->nbl_lru, &reaplist);
+		list_del_init(&nbl->nbl_list);
+	}
+	spin_unlock(&nn->client_lock);
+
+	while (!list_empty(&reaplist)) {
+		nbl = list_first_entry(&nn->blocked_locks_lru,
+					struct nfsd4_blocked_lock, nbl_lru);
+		list_del_init(&nbl->nbl_lru);
+		posix_unblock_lock(&nbl->nbl_lock);
+		free_blocked_lock(nbl);
+	}
+
 	nfsd4_client_tracking_exit(net);
 	nfs4_state_destroy_net(net);
 }
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index e45c183a8bf7..c9399366f9df 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -587,6 +587,8 @@ static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b)
  */
 struct nfsd4_blocked_lock {
 	struct list_head	nbl_list;
+	struct list_head	nbl_lru;
+	unsigned long		nbl_time;
 	struct file_lock	nbl_lock;
 	struct knfsd_fh		nbl_fh;
 	struct nfsd4_callback	nbl_cb;
-- 
cgit v1.2.3


From 19e4c3477f70843930b328be3bcd16bd17993911 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@redhat.com>
Date: Fri, 16 Sep 2016 16:28:27 -0400
Subject: nfsd: set the MAY_NOTIFY_LOCK flag in OPEN replies

If we are using v4.1+, then we can send notification when contended
locks become free. Inform the client of that fact.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4state.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

(limited to 'fs')

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 6c74d9a45163..4062f4fbfc6d 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -4490,9 +4490,11 @@ out:
 	* To finish the open response, we just need to set the rflags.
 	*/
 	open->op_rflags = NFS4_OPEN_RESULT_LOCKTYPE_POSIX;
-	if (!(open->op_openowner->oo_flags & NFS4_OO_CONFIRMED) &&
-	    !nfsd4_has_session(&resp->cstate))
+	if (nfsd4_has_session(&resp->cstate))
+		open->op_rflags |= NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK;
+	else if (!(open->op_openowner->oo_flags & NFS4_OO_CONFIRMED))
 		open->op_rflags |= NFS4_OPEN_RESULT_CONFIRM;
+
 	if (dp)
 		nfs4_put_stid(&dp->dl_stid);
 	if (stp)
-- 
cgit v1.2.3


From ebd7c72c63acc3d00944c88cbf96143a8cae179f Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@redhat.com>
Date: Mon, 12 Sep 2016 16:00:47 -0400
Subject: nfsd: randomize SETCLIENTID reply to help distinguish servers

NFSv4.1 has built-in trunking support that allows a client to determine
whether two connections to two different IP addresses are actually to
the same server.  NFSv4.0 does not, but RFC 7931 attempts to provide
clients a means to do this, basically by performing a SETCLIENTID to one
address and confirming it with a SETCLIENTID_CONFIRM to the other.

Linux clients since 05f4c350ee02 "NFS: Discover NFSv4 server trunking
when mounting" implement a variation on this suggestion.  It is possible
that other clients do too.

This depends on the clientid and verifier not being accepted by an
unrelated server.  Since both are 64-bit values, that would be very
unlikely if they were random numbers.  But they aren't:

knfsd generates the 64-bit clientid by concatenating the 32-bit boot
time (in seconds) and a counter.  This makes collisions between
clientids generated by the same server extremely unlikely.  But
collisions are very likely between clientids generated by servers that
boot at the same time, and it's quite common for multiple servers to
boot at the same time.  The verifier is a concatenation of the
SETCLIENTID time (in seconds) and a counter, so again collisions between
different servers are likely if multiple SETCLIENTIDs are done at the
same time, which is a common case.

Therefore recent NFSv4.0 clients may decide two different servers are
really the same, and mount a filesystem from the wrong server.

Fortunately the Linux client, since 55b9df93ddd6 "nfsv4/v4.1: Verify the
client owner id during trunking detection", only does this when given
the non-default "migration" mount option.

The fault is really with RFC 7931, and needs a client fix, but in the
meantime we can mitigate the chance of these collisions by randomizing
the starting value of the counters used to generate clientids and
verifiers.

Reported-by: Frank Sorenson <fsorenso@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfsctl.c | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'fs')

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 65ad0165a94f..36b2af931e06 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -1216,6 +1216,8 @@ static __net_init int nfsd_init_net(struct net *net)
 		goto out_idmap_error;
 	nn->nfsd4_lease = 90;	/* default lease time */
 	nn->nfsd4_grace = 90;
+	nn->clverifier_counter = prandom_u32();
+	nn->clientid_counter = prandom_u32();
 	return 0;
 
 out_idmap_error:
-- 
cgit v1.2.3


From 7d22fc11c7edeeac6f1c3f1ae0edcef4de08c6e0 Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@redhat.com>
Date: Tue, 20 Sep 2016 20:55:36 -0400
Subject: nfsd4: setclientid_confirm with unmatched verifier should fail

A setclientid_confirm with (clientid, verifier) both matching an
existing confirmed record is assumed to be a replay, but if the verifier
doesn't match, it shouldn't be.

This would be a very rare case, except that clients following
https://tools.ietf.org/html/rfc7931#section-5.8 may depend on the
failure.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4state.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

(limited to 'fs')

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 4062f4fbfc6d..a0e5128ec539 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3304,9 +3304,10 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
 		goto out;
 	/* cases below refer to rfc 3530 section 14.2.34: */
 	if (!unconf || !same_verf(&confirm, &unconf->cl_confirm)) {
-		if (conf && !unconf) /* case 2: probable retransmit */
+		if (conf && same_verf(&confirm, &conf->cl_confirm)) {
+			/* case 2: probable retransmit */
 			status = nfs_ok;
-		else /* case 4: client hasn't noticed we rebooted yet? */
+		} else /* case 4: client hasn't noticed we rebooted yet? */
 			status = nfserr_stale_clientid;
 		goto out;
 	}
-- 
cgit v1.2.3


From 09bb8bfffd29c3dffb72bc2c69a062dfb1ae624c Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@suse.com>
Date: Thu, 4 Aug 2016 10:19:06 +1000
Subject: exportfs: be careful to only return expected errors.

When nfsd calls fh_to_dentry, it expect ESTALE or ENOMEM as errors.
In particular it can be tempting to return ENOENT, but this is not
handled well by nfsd.

Rather than requiring strict adherence to error code code filesystems,
treat all unexpected error codes the same as ESTALE.  This is safest.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/exportfs/expfs.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

(limited to 'fs')

diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c
index 207ba8d627ca..a4b531be9168 100644
--- a/fs/exportfs/expfs.c
+++ b/fs/exportfs/expfs.c
@@ -428,10 +428,10 @@ struct dentry *exportfs_decode_fh(struct vfsmount *mnt, struct fid *fid,
 	if (!nop || !nop->fh_to_dentry)
 		return ERR_PTR(-ESTALE);
 	result = nop->fh_to_dentry(mnt->mnt_sb, fid, fh_len, fileid_type);
-	if (!result)
-		result = ERR_PTR(-ESTALE);
-	if (IS_ERR(result))
-		return result;
+	if (PTR_ERR(result) == -ENOMEM)
+		return ERR_CAST(result);
+	if (IS_ERR_OR_NULL(result))
+		return ERR_PTR(-ESTALE);
 
 	if (d_is_dir(result)) {
 		/*
@@ -541,6 +541,8 @@ struct dentry *exportfs_decode_fh(struct vfsmount *mnt, struct fid *fid,
 
  err_result:
 	dput(result);
+	if (err != -ENOMEM)
+		err = -ESTALE;
 	return ERR_PTR(err);
 }
 EXPORT_SYMBOL_GPL(exportfs_decode_fh);
-- 
cgit v1.2.3


From ff30f08c32f932272f9bd4c1caca824ffc939346 Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@redhat.com>
Date: Tue, 4 Oct 2016 12:53:49 -0400
Subject: nfsd: only WARN once on unmapped errors

No need to spam the logs here.

The only drawback is losing information if we ever encounter two
different unmapped errors, but in practice we've rarely see even one.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfsproc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'fs')

diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
index e9214768cde9..a56ee10204d9 100644
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -798,7 +798,7 @@ nfserrno (int errno)
 		if (nfs_errtbl[i].syserr == errno)
 			return nfs_errtbl[i].nfserr;
 	}
-	WARN(1, "nfsd: non-standard errno: %d\n", errno);
+	WARN_ONCE(1, "nfsd: non-standard errno: %d\n", errno);
 	return nfserr_io;
 }
 
-- 
cgit v1.2.3


From 42e616167abb7e4074cfba3a2ca19fa2aba40048 Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@redhat.com>
Date: Tue, 4 Oct 2016 13:57:43 -0400
Subject: nfsd: handle EUCLEAN

Eric Sandeen reports that xfs can return this if filesystem corruption
prevented completing the operation.

Reported-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfsproc.c | 1 +
 1 file changed, 1 insertion(+)

(limited to 'fs')

diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
index a56ee10204d9..78cd77042a25 100644
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -791,6 +791,7 @@ nfserrno (int errno)
 		{ nfserr_toosmall, -ETOOSMALL },
 		{ nfserr_serverfault, -ESERVERFAULT },
 		{ nfserr_serverfault, -ENFILE },
+		{ nfserr_io, -EUCLEAN },
 	};
 	int	i;
 
-- 
cgit v1.2.3


From 29ae7f9dc21a7dda41d78b27bbda7d427ece8ad4 Mon Sep 17 00:00:00 2001
From: Anna Schumaker <Anna.Schumaker@netapp.com>
Date: Wed, 7 Sep 2016 15:57:30 -0400
Subject: NFSD: Implement the COPY call

I only implemented the sync version of this call, since it's the
easiest.  I can simply call vfs_copy_range() and have the vfs do the
right thing for the filesystem being exported.

Signed-off-by: Anna Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4proc.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++-------
 fs/nfsd/nfs4xdr.c  | 63 ++++++++++++++++++++++++++++++++++++--
 fs/nfsd/vfs.c      | 16 ++++++++++
 fs/nfsd/vfs.h      |  2 ++
 fs/nfsd/xdr4.h     | 23 ++++++++++++++
 5 files changed, 181 insertions(+), 13 deletions(-)

(limited to 'fs')

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 1fb222752b2b..abb09b580389 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1010,46 +1010,96 @@ nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 }
 
 static __be32
-nfsd4_clone(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
-		struct nfsd4_clone *clone)
+nfsd4_verify_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
+		  stateid_t *src_stateid, struct file **src,
+		  stateid_t *dst_stateid, struct file **dst)
 {
-	struct file *src, *dst;
 	__be32 status;
 
 	status = nfs4_preprocess_stateid_op(rqstp, cstate, &cstate->save_fh,
-					    &clone->cl_src_stateid, RD_STATE,
-					    &src, NULL);
+					    src_stateid, RD_STATE, src, NULL);
 	if (status) {
 		dprintk("NFSD: %s: couldn't process src stateid!\n", __func__);
 		goto out;
 	}
 
 	status = nfs4_preprocess_stateid_op(rqstp, cstate, &cstate->current_fh,
-					    &clone->cl_dst_stateid, WR_STATE,
-					    &dst, NULL);
+					    dst_stateid, WR_STATE, dst, NULL);
 	if (status) {
 		dprintk("NFSD: %s: couldn't process dst stateid!\n", __func__);
 		goto out_put_src;
 	}
 
 	/* fix up for NFS-specific error code */
-	if (!S_ISREG(file_inode(src)->i_mode) ||
-	    !S_ISREG(file_inode(dst)->i_mode)) {
+	if (!S_ISREG(file_inode(*src)->i_mode) ||
+	    !S_ISREG(file_inode(*dst)->i_mode)) {
 		status = nfserr_wrong_type;
 		goto out_put_dst;
 	}
 
+out:
+	return status;
+out_put_dst:
+	fput(*dst);
+out_put_src:
+	fput(*src);
+	goto out;
+}
+
+static __be32
+nfsd4_clone(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
+		struct nfsd4_clone *clone)
+{
+	struct file *src, *dst;
+	__be32 status;
+
+	status = nfsd4_verify_copy(rqstp, cstate, &clone->cl_src_stateid, &src,
+				   &clone->cl_dst_stateid, &dst);
+	if (status)
+		goto out;
+
 	status = nfsd4_clone_file_range(src, clone->cl_src_pos,
 			dst, clone->cl_dst_pos, clone->cl_count);
 
-out_put_dst:
 	fput(dst);
-out_put_src:
 	fput(src);
 out:
 	return status;
 }
 
+static __be32
+nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
+		struct nfsd4_copy *copy)
+{
+	struct file *src, *dst;
+	__be32 status;
+	ssize_t bytes;
+
+	status = nfsd4_verify_copy(rqstp, cstate, &copy->cp_src_stateid, &src,
+				   &copy->cp_dst_stateid, &dst);
+	if (status)
+		goto out;
+
+	bytes = nfsd_copy_file_range(src, copy->cp_src_pos,
+			dst, copy->cp_dst_pos, copy->cp_count);
+
+	if (bytes < 0)
+		status = nfserrno(bytes);
+	else {
+		copy->cp_res.wr_bytes_written = bytes;
+		copy->cp_res.wr_stable_how = NFS_UNSTABLE;
+		copy->cp_consecutive = 1;
+		copy->cp_synchronous = 1;
+		gen_boot_verifier(&copy->cp_res.wr_verifier, SVC_NET(rqstp));
+		status = nfs_ok;
+	}
+
+	fput(src);
+	fput(dst);
+out:
+	return status;
+}
+
 static __be32
 nfsd4_fallocate(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 		struct nfsd4_fallocate *fallocate, int flags)
@@ -1966,6 +2016,18 @@ static inline u32 nfsd4_create_session_rsize(struct svc_rqst *rqstp, struct nfsd
 		op_encode_channel_attrs_maxsz) * sizeof(__be32);
 }
 
+static inline u32 nfsd4_copy_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
+{
+	return (op_encode_hdr_size +
+		1 /* wr_callback */ +
+		op_encode_stateid_maxsz /* wr_callback */ +
+		2 /* wr_count */ +
+		1 /* wr_committed */ +
+		op_encode_verifier_maxsz +
+		1 /* cr_consecutive */ +
+		1 /* cr_synchronous */) * sizeof(__be32);
+}
+
 #ifdef CONFIG_NFSD_PNFS
 /*
  * At this stage we don't really know what layout driver will handle the request,
@@ -2328,6 +2390,12 @@ static struct nfsd4_operation nfsd4_ops[] = {
 		.op_name = "OP_CLONE",
 		.op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
 	},
+	[OP_COPY] = {
+		.op_func = (nfsd4op_func)nfsd4_copy,
+		.op_flags = OP_MODIFIES_SOMETHING | OP_CACHEME,
+		.op_name = "OP_COPY",
+		.op_rsize_bop = (nfsd4op_rsize)nfsd4_copy_rsize,
+	},
 	[OP_SEEK] = {
 		.op_func = (nfsd4op_func)nfsd4_seek,
 		.op_name = "OP_SEEK",
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 7f8232e32dc7..c2d2895a1ec1 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1693,6 +1693,30 @@ nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
 	DECODE_TAIL;
 }
 
+static __be32
+nfsd4_decode_copy(struct nfsd4_compoundargs *argp, struct nfsd4_copy *copy)
+{
+	DECODE_HEAD;
+	unsigned int tmp;
+
+	status = nfsd4_decode_stateid(argp, &copy->cp_src_stateid);
+	if (status)
+		return status;
+	status = nfsd4_decode_stateid(argp, &copy->cp_dst_stateid);
+	if (status)
+		return status;
+
+	READ_BUF(8 + 8 + 8 + 4 + 4 + 4);
+	p = xdr_decode_hyper(p, &copy->cp_src_pos);
+	p = xdr_decode_hyper(p, &copy->cp_dst_pos);
+	p = xdr_decode_hyper(p, &copy->cp_count);
+	copy->cp_consecutive = be32_to_cpup(p++);
+	copy->cp_synchronous = be32_to_cpup(p++);
+	tmp = be32_to_cpup(p); /* Source server list not supported */
+
+	DECODE_TAIL;
+}
+
 static __be32
 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
 {
@@ -1793,7 +1817,7 @@ static nfsd4_dec nfsd4_dec_ops[] = {
 
 	/* new operations for NFSv4.2 */
 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
-	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_notsupp,
+	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_copy,
 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
@@ -4201,6 +4225,41 @@ nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
 }
 #endif /* CONFIG_NFSD_PNFS */
 
+static __be32
+nfsd42_encode_write_res(struct nfsd4_compoundres *resp, struct nfsd42_write_res *write)
+{
+	__be32 *p;
+
+	p = xdr_reserve_space(&resp->xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE);
+	if (!p)
+		return nfserr_resource;
+
+	*p++ = cpu_to_be32(0);
+	p = xdr_encode_hyper(p, write->wr_bytes_written);
+	*p++ = cpu_to_be32(write->wr_stable_how);
+	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
+				    NFS4_VERIFIER_SIZE);
+	return nfs_ok;
+}
+
+static __be32
+nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr,
+		  struct nfsd4_copy *copy)
+{
+	__be32 *p;
+
+	if (!nfserr) {
+		nfserr = nfsd42_encode_write_res(resp, &copy->cp_res);
+		if (nfserr)
+			return nfserr;
+
+		p = xdr_reserve_space(&resp->xdr, 4 + 4);
+		*p++ = cpu_to_be32(copy->cp_consecutive);
+		*p++ = cpu_to_be32(copy->cp_synchronous);
+	}
+	return nfserr;
+}
+
 static __be32
 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
 		  struct nfsd4_seek *seek)
@@ -4300,7 +4359,7 @@ static nfsd4_enc nfsd4_enc_ops[] = {
 
 	/* NFSv4.2 operations */
 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
-	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_noop,
+	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_copy,
 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index ff476e654b8f..8ca642fe9b21 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -513,6 +513,22 @@ __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst,
 			count));
 }
 
+ssize_t nfsd_copy_file_range(struct file *src, u64 src_pos, struct file *dst,
+			     u64 dst_pos, u64 count)
+{
+
+	/*
+	 * Limit copy to 4MB to prevent indefinitely blocking an nfsd
+	 * thread and client rpc slot.  The choice of 4MB is somewhat
+	 * arbitrary.  We might instead base this on r/wsize, or make it
+	 * tunable, or use a time instead of a byte limit, or implement
+	 * asynchronous copy.  In theory a client could also recognize a
+	 * limit like this and pipeline multiple COPY requests.
+	 */
+	count = min_t(u64, count, 1 << 22);
+	return vfs_copy_file_range(src, src_pos, dst, dst_pos, count, 0);
+}
+
 __be32 nfsd4_vfs_fallocate(struct svc_rqst *rqstp, struct svc_fh *fhp,
 			   struct file *file, loff_t offset, loff_t len,
 			   int flags)
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index 3cbb1b33777b..0bf9e7bf5800 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -96,6 +96,8 @@ __be32		nfsd_symlink(struct svc_rqst *, struct svc_fh *,
 				struct svc_fh *res);
 __be32		nfsd_link(struct svc_rqst *, struct svc_fh *,
 				char *, int, struct svc_fh *);
+ssize_t		nfsd_copy_file_range(struct file *, u64,
+				     struct file *, u64, u64);
 __be32		nfsd_rename(struct svc_rqst *,
 				struct svc_fh *, char *, int,
 				struct svc_fh *, char *, int);
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index beea0c5edc51..8fda4abdf3b1 100644
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -503,6 +503,28 @@ struct nfsd4_clone {
 	u64		cl_count;
 };
 
+struct nfsd42_write_res {
+	u64			wr_bytes_written;
+	u32			wr_stable_how;
+	nfs4_verifier		wr_verifier;
+};
+
+struct nfsd4_copy {
+	/* request */
+	stateid_t	cp_src_stateid;
+	stateid_t	cp_dst_stateid;
+	u64		cp_src_pos;
+	u64		cp_dst_pos;
+	u64		cp_count;
+
+	/* both */
+	bool		cp_consecutive;
+	bool		cp_synchronous;
+
+	/* response */
+	struct nfsd42_write_res	cp_res;
+};
+
 struct nfsd4_seek {
 	/* request */
 	stateid_t	seek_stateid;
@@ -568,6 +590,7 @@ struct nfsd4_op {
 		struct nfsd4_fallocate		allocate;
 		struct nfsd4_fallocate		deallocate;
 		struct nfsd4_clone		clone;
+		struct nfsd4_copy		copy;
 		struct nfsd4_seek		seek;
 	} u;
 	struct nfs4_replay *			replay;
-- 
cgit v1.2.3