Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 694 insertions, 0 deletions

diff --git a/fs/lockd/host.c b/fs/lockd/host.c
new file mode 100644
index 000000000..cdc8e12cd
--- /dev/null
+++ b/fs/lockd/host.c
@@ -0,0 +1,694 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/lockd/host.c
+ *
+ * Management for NLM peer hosts. The nlm_host struct is shared
+ * between client and server implementation. The only reason to
+ * do so is to reduce code bloat.
+ *
+ * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/addr.h>
+#include <linux/sunrpc/svc.h>
+#include <linux/lockd/lockd.h>
+#include <linux/mutex.h>
+
+#include <linux/sunrpc/svc_xprt.h>
+
+#include <net/ipv6.h>
+
+#include "netns.h"
+
+#define NLMDBG_FACILITY		NLMDBG_HOSTCACHE
+#define NLM_HOST_NRHASH		32
+#define NLM_HOST_REBIND		(60 * HZ)
+#define NLM_HOST_EXPIRE		(300 * HZ)
+#define NLM_HOST_COLLECT	(120 * HZ)
+
+static struct hlist_head	nlm_server_hosts[NLM_HOST_NRHASH];
+static struct hlist_head	nlm_client_hosts[NLM_HOST_NRHASH];
+
+#define for_each_host(host, chain, table) \
+	for ((chain) = (table); \
+	     (chain) < (table) + NLM_HOST_NRHASH; ++(chain)) \
+		hlist_for_each_entry((host), (chain), h_hash)
+
+#define for_each_host_safe(host, next, chain, table) \
+	for ((chain) = (table); \
+	     (chain) < (table) + NLM_HOST_NRHASH; ++(chain)) \
+		hlist_for_each_entry_safe((host), (next), \
+						(chain), h_hash)
+
+static unsigned long		nrhosts;
+static DEFINE_MUTEX(nlm_host_mutex);
+
+static void			nlm_gc_hosts(struct net *net);
+
+struct nlm_lookup_host_info {
+	const int		server;		/* search for server|client */
+	const struct sockaddr	*sap;		/* address to search for */
+	const size_t		salen;		/* it's length */
+	const unsigned short	protocol;	/* transport to search for*/
+	const u32		version;	/* NLM version to search for */
+	const char		*hostname;	/* remote's hostname */
+	const size_t		hostname_len;	/* it's length */
+	const int		noresvport;	/* use non-priv port */
+	struct net		*net;		/* network namespace to bind */
+	const struct cred	*cred;
+};
+
+/*
+ * Hash function must work well on big- and little-endian platforms
+ */
+static unsigned int __nlm_hash32(const __be32 n)
+{
+	unsigned int hash = (__force u32)n ^ ((__force u32)n >> 16);
+	return hash ^ (hash >> 8);
+}
+
+static unsigned int __nlm_hash_addr4(const struct sockaddr *sap)
+{
+	const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
+	return __nlm_hash32(sin->sin_addr.s_addr);
+}
+
+static unsigned int __nlm_hash_addr6(const struct sockaddr *sap)
+{
+	const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
+	const struct in6_addr addr = sin6->sin6_addr;
+	return __nlm_hash32(addr.s6_addr32[0]) ^
+	       __nlm_hash32(addr.s6_addr32[1]) ^
+	       __nlm_hash32(addr.s6_addr32[2]) ^
+	       __nlm_hash32(addr.s6_addr32[3]);
+}
+
+static unsigned int nlm_hash_address(const struct sockaddr *sap)
+{
+	unsigned int hash;
+
+	switch (sap->sa_family) {
+	case AF_INET:
+		hash = __nlm_hash_addr4(sap);
+		break;
+	case AF_INET6:
+		hash = __nlm_hash_addr6(sap);
+		break;
+	default:
+		hash = 0;
+	}
+	return hash & (NLM_HOST_NRHASH - 1);
+}
+
+/*
+ * Allocate and initialize an nlm_host.  Common to both client and server.
+ */
+static struct nlm_host *nlm_alloc_host(struct nlm_lookup_host_info *ni,
+				       struct nsm_handle *nsm)
+{
+	struct nlm_host *host = NULL;
+	unsigned long now = jiffies;
+
+	if (nsm != NULL)
+		refcount_inc(&nsm->sm_count);
+	else {
+		host = NULL;
+		nsm = nsm_get_handle(ni->net, ni->sap, ni->salen,
+					ni->hostname, ni->hostname_len);
+		if (unlikely(nsm == NULL)) {
+			dprintk("lockd: %s failed; no nsm handle\n",
+				__func__);
+			goto out;
+		}
+	}
+
+	host = kmalloc(sizeof(*host), GFP_KERNEL);
+	if (unlikely(host == NULL)) {
+		dprintk("lockd: %s failed; no memory\n", __func__);
+		nsm_release(nsm);
+		goto out;
+	}
+
+	memcpy(nlm_addr(host), ni->sap, ni->salen);
+	host->h_addrlen    = ni->salen;
+	rpc_set_port(nlm_addr(host), 0);
+	host->h_srcaddrlen = 0;
+
+	host->h_rpcclnt    = NULL;
+	host->h_name	   = nsm->sm_name;
+	host->h_version    = ni->version;
+	host->h_proto      = ni->protocol;
+	host->h_reclaiming = 0;
+	host->h_server     = ni->server;
+	host->h_noresvport = ni->noresvport;
+	host->h_inuse      = 0;
+	init_waitqueue_head(&host->h_gracewait);
+	init_rwsem(&host->h_rwsem);
+	host->h_state      = 0;
+	host->h_nsmstate   = 0;
+	host->h_pidcount   = 0;
+	refcount_set(&host->h_count, 1);
+	mutex_init(&host->h_mutex);
+	host->h_nextrebind = now + NLM_HOST_REBIND;
+	host->h_expires    = now + NLM_HOST_EXPIRE;
+	INIT_LIST_HEAD(&host->h_lockowners);
+	spin_lock_init(&host->h_lock);
+	INIT_LIST_HEAD(&host->h_granted);
+	INIT_LIST_HEAD(&host->h_reclaim);
+	host->h_nsmhandle  = nsm;
+	host->h_addrbuf    = nsm->sm_addrbuf;
+	host->net	   = ni->net;
+	host->h_cred	   = get_cred(ni->cred);
+	strscpy(host->nodename, utsname()->nodename, sizeof(host->nodename));
+
+out:
+	return host;
+}
+
+/*
+ * Destroy an nlm_host and free associated resources
+ *
+ * Caller must hold nlm_host_mutex.
+ */
+static void nlm_destroy_host_locked(struct nlm_host *host)
+{
+	struct rpc_clnt	*clnt;
+	struct lockd_net *ln = net_generic(host->net, lockd_net_id);
+
+	dprintk("lockd: destroy host %s\n", host->h_name);
+
+	hlist_del_init(&host->h_hash);
+
+	nsm_unmonitor(host);
+	nsm_release(host->h_nsmhandle);
+
+	clnt = host->h_rpcclnt;
+	if (clnt != NULL)
+		rpc_shutdown_client(clnt);
+	put_cred(host->h_cred);
+	kfree(host);
+
+	ln->nrhosts--;
+	nrhosts--;
+}
+
+/**
+ * nlmclnt_lookup_host - Find an NLM host handle matching a remote server
+ * @sap: network address of server
+ * @salen: length of server address
+ * @protocol: transport protocol to use
+ * @version: NLM protocol version
+ * @hostname: '\0'-terminated hostname of server
+ * @noresvport: 1 if non-privileged port should be used
+ * @net: pointer to net namespace
+ * @cred: pointer to cred
+ *
+ * Returns an nlm_host structure that matches the passed-in
+ * [server address, transport protocol, NLM version, server hostname].
+ * If one doesn't already exist in the host cache, a new handle is
+ * created and returned.
+ */
+struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap,
+				     const size_t salen,
+				     const unsigned short protocol,
+				     const u32 version,
+				     const char *hostname,
+				     int noresvport,
+				     struct net *net,
+				     const struct cred *cred)
+{
+	struct nlm_lookup_host_info ni = {
+		.server		= 0,
+		.sap		= sap,
+		.salen		= salen,
+		.protocol	= protocol,
+		.version	= version,
+		.hostname	= hostname,
+		.hostname_len	= strlen(hostname),
+		.noresvport	= noresvport,
+		.net		= net,
+		.cred		= cred,
+	};
+	struct hlist_head *chain;
+	struct nlm_host	*host;
+	struct nsm_handle *nsm = NULL;
+	struct lockd_net *ln = net_generic(net, lockd_net_id);
+
+	dprintk("lockd: %s(host='%s', vers=%u, proto=%s)\n", __func__,
+			(hostname ? hostname : "<none>"), version,
+			(protocol == IPPROTO_UDP ? "udp" : "tcp"));
+
+	mutex_lock(&nlm_host_mutex);
+
+	chain = &nlm_client_hosts[nlm_hash_address(sap)];
+	hlist_for_each_entry(host, chain, h_hash) {
+		if (host->net != net)
+			continue;
+		if (!rpc_cmp_addr(nlm_addr(host), sap))
+			continue;
+
+		/* Same address. Share an NSM handle if we already have one */
+		if (nsm == NULL)
+			nsm = host->h_nsmhandle;
+
+		if (host->h_proto != protocol)
+			continue;
+		if (host->h_version != version)
+			continue;
+
+		nlm_get_host(host);
+		dprintk("lockd: %s found host %s (%s)\n", __func__,
+			host->h_name, host->h_addrbuf);
+		goto out;
+	}
+
+	host = nlm_alloc_host(&ni, nsm);
+	if (unlikely(host == NULL))
+		goto out;
+
+	hlist_add_head(&host->h_hash, chain);
+	ln->nrhosts++;
+	nrhosts++;
+
+	dprintk("lockd: %s created host %s (%s)\n", __func__,
+		host->h_name, host->h_addrbuf);
+
+out:
+	mutex_unlock(&nlm_host_mutex);
+	return host;
+}
+
+/**
+ * nlmclnt_release_host - release client nlm_host
+ * @host: nlm_host to release
+ *
+ */
+void nlmclnt_release_host(struct nlm_host *host)
+{
+	if (host == NULL)
+		return;
+
+	dprintk("lockd: release client host %s\n", host->h_name);
+
+	WARN_ON_ONCE(host->h_server);
+
+	if (refcount_dec_and_mutex_lock(&host->h_count, &nlm_host_mutex)) {
+		WARN_ON_ONCE(!list_empty(&host->h_lockowners));
+		WARN_ON_ONCE(!list_empty(&host->h_granted));
+		WARN_ON_ONCE(!list_empty(&host->h_reclaim));
+
+		nlm_destroy_host_locked(host);
+		mutex_unlock(&nlm_host_mutex);
+	}
+}
+
+/**
+ * nlmsvc_lookup_host - Find an NLM host handle matching a remote client
+ * @rqstp: incoming NLM request
+ * @hostname: name of client host
+ * @hostname_len: length of client hostname
+ *
+ * Returns an nlm_host structure that matches the [client address,
+ * transport protocol, NLM version, client hostname] of the passed-in
+ * NLM request.  If one doesn't already exist in the host cache, a
+ * new handle is created and returned.
+ *
+ * Before possibly creating a new nlm_host, construct a sockaddr
+ * for a specific source address in case the local system has
+ * multiple network addresses.  The family of the address in
+ * rq_daddr is guaranteed to be the same as the family of the
+ * address in rq_addr, so it's safe to use the same family for
+ * the source address.
+ */
+struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
+				    const char *hostname,
+				    const size_t hostname_len)
+{
+	struct hlist_head *chain;
+	struct nlm_host	*host = NULL;
+	struct nsm_handle *nsm = NULL;
+	struct sockaddr *src_sap = svc_daddr(rqstp);
+	size_t src_len = rqstp->rq_daddrlen;
+	struct net *net = SVC_NET(rqstp);
+	struct nlm_lookup_host_info ni = {
+		.server		= 1,
+		.sap		= svc_addr(rqstp),
+		.salen		= rqstp->rq_addrlen,
+		.protocol	= rqstp->rq_prot,
+		.version	= rqstp->rq_vers,
+		.hostname	= hostname,
+		.hostname_len	= hostname_len,
+		.net		= net,
+	};
+	struct lockd_net *ln = net_generic(net, lockd_net_id);
+
+	dprintk("lockd: %s(host='%.*s', vers=%u, proto=%s)\n", __func__,
+			(int)hostname_len, hostname, rqstp->rq_vers,
+			(rqstp->rq_prot == IPPROTO_UDP ? "udp" : "tcp"));
+
+	mutex_lock(&nlm_host_mutex);
+
+	if (time_after_eq(jiffies, ln->next_gc))
+		nlm_gc_hosts(net);
+
+	chain = &nlm_server_hosts[nlm_hash_address(ni.sap)];
+	hlist_for_each_entry(host, chain, h_hash) {
+		if (host->net != net)
+			continue;
+		if (!rpc_cmp_addr(nlm_addr(host), ni.sap))
+			continue;
+
+		/* Same address. Share an NSM handle if we already have one */
+		if (nsm == NULL)
+			nsm = host->h_nsmhandle;
+
+		if (host->h_proto != ni.protocol)
+			continue;
+		if (host->h_version != ni.version)
+			continue;
+		if (!rpc_cmp_addr(nlm_srcaddr(host), src_sap))
+			continue;
+
+		/* Move to head of hash chain. */
+		hlist_del(&host->h_hash);
+		hlist_add_head(&host->h_hash, chain);
+
+		nlm_get_host(host);
+		dprintk("lockd: %s found host %s (%s)\n",
+			__func__, host->h_name, host->h_addrbuf);
+		goto out;
+	}
+
+	host = nlm_alloc_host(&ni, nsm);
+	if (unlikely(host == NULL))
+		goto out;
+
+	memcpy(nlm_srcaddr(host), src_sap, src_len);
+	host->h_srcaddrlen = src_len;
+	hlist_add_head(&host->h_hash, chain);
+	ln->nrhosts++;
+	nrhosts++;
+
+	refcount_inc(&host->h_count);
+
+	dprintk("lockd: %s created host %s (%s)\n",
+		__func__, host->h_name, host->h_addrbuf);
+
+out:
+	mutex_unlock(&nlm_host_mutex);
+	return host;
+}
+
+/**
+ * nlmsvc_release_host - release server nlm_host
+ * @host: nlm_host to release
+ *
+ * Host is destroyed later in nlm_gc_host().
+ */
+void nlmsvc_release_host(struct nlm_host *host)
+{
+	if (host == NULL)
+		return;
+
+	dprintk("lockd: release server host %s\n", host->h_name);
+
+	WARN_ON_ONCE(!host->h_server);
+	refcount_dec(&host->h_count);
+}
+
+/*
+ * Create the NLM RPC client for an NLM peer
+ */
+struct rpc_clnt *
+nlm_bind_host(struct nlm_host *host)
+{
+	struct rpc_clnt	*clnt;
+
+	dprintk("lockd: nlm_bind_host %s (%s)\n",
+			host->h_name, host->h_addrbuf);
+
+	/* Lock host handle */
+	mutex_lock(&host->h_mutex);
+
+	/* If we've already created an RPC client, check whether
+	 * RPC rebind is required
+	 */
+	if ((clnt = host->h_rpcclnt) != NULL) {
+		nlm_rebind_host(host);
+	} else {
+		unsigned long increment = nlmsvc_timeout;
+		struct rpc_timeout timeparms = {
+			.to_initval	= increment,
+			.to_increment	= increment,
+			.to_maxval	= increment * 6UL,
+			.to_retries	= 5U,
+		};
+		struct rpc_create_args args = {
+			.net		= host->net,
+			.protocol	= host->h_proto,
+			.address	= nlm_addr(host),
+			.addrsize	= host->h_addrlen,
+			.timeout	= &timeparms,
+			.servername	= host->h_name,
+			.program	= &nlm_program,
+			.version	= host->h_version,
+			.authflavor	= RPC_AUTH_UNIX,
+			.flags		= (RPC_CLNT_CREATE_NOPING |
+					   RPC_CLNT_CREATE_AUTOBIND |
+					   RPC_CLNT_CREATE_REUSEPORT),
+			.cred		= host->h_cred,
+		};
+
+		/*
+		 * lockd retries server side blocks automatically so we want
+		 * those to be soft RPC calls. Client side calls need to be
+		 * hard RPC tasks.
+		 */
+		if (!host->h_server)
+			args.flags |= RPC_CLNT_CREATE_HARDRTRY;
+		if (host->h_noresvport)
+			args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
+		if (host->h_srcaddrlen)
+			args.saddress = nlm_srcaddr(host);
+
+		clnt = rpc_create(&args);
+		if (!IS_ERR(clnt))
+			host->h_rpcclnt = clnt;
+		else {
+			printk("lockd: couldn't create RPC handle for %s\n", host->h_name);
+			clnt = NULL;
+		}
+	}
+
+	mutex_unlock(&host->h_mutex);
+	return clnt;
+}
+
+/**
+ * nlm_rebind_host - If needed, force a portmap lookup of the peer's lockd port
+ * @host: NLM host handle for peer
+ *
+ * This is not needed when using a connection-oriented protocol, such as TCP.
+ * The existing autobind mechanism is sufficient to force a rebind when
+ * required, e.g. on connection state transitions.
+ */
+void
+nlm_rebind_host(struct nlm_host *host)
+{
+	if (host->h_proto != IPPROTO_UDP)
+		return;
+
+	if (host->h_rpcclnt && time_after_eq(jiffies, host->h_nextrebind)) {
+		rpc_force_rebind(host->h_rpcclnt);
+		host->h_nextrebind = jiffies + NLM_HOST_REBIND;
+	}
+}
+
+/*
+ * Increment NLM host count
+ */
+struct nlm_host * nlm_get_host(struct nlm_host *host)
+{
+	if (host) {
+		dprintk("lockd: get host %s\n", host->h_name);
+		refcount_inc(&host->h_count);
+		host->h_expires = jiffies + NLM_HOST_EXPIRE;
+	}
+	return host;
+}
+
+static struct nlm_host *next_host_state(struct hlist_head *cache,
+					struct nsm_handle *nsm,
+					const struct nlm_reboot *info)
+{
+	struct nlm_host *host;
+	struct hlist_head *chain;
+
+	mutex_lock(&nlm_host_mutex);
+	for_each_host(host, chain, cache) {
+		if (host->h_nsmhandle == nsm
+		    && host->h_nsmstate != info->state) {
+			host->h_nsmstate = info->state;
+			host->h_state++;
+
+			nlm_get_host(host);
+			mutex_unlock(&nlm_host_mutex);
+			return host;
+		}
+	}
+
+	mutex_unlock(&nlm_host_mutex);
+	return NULL;
+}
+
+/**
+ * nlm_host_rebooted - Release all resources held by rebooted host
+ * @net:  network namespace
+ * @info: pointer to decoded results of NLM_SM_NOTIFY call
+ *
+ * We were notified that the specified host has rebooted.  Release
+ * all resources held by that peer.
+ */
+void nlm_host_rebooted(const struct net *net, const struct nlm_reboot *info)
+{
+	struct nsm_handle *nsm;
+	struct nlm_host	*host;
+
+	nsm = nsm_reboot_lookup(net, info);
+	if (unlikely(nsm == NULL))
+		return;
+
+	/* Mark all hosts tied to this NSM state as having rebooted.
+	 * We run the loop repeatedly, because we drop the host table
+	 * lock for this.
+	 * To avoid processing a host several times, we match the nsmstate.
+	 */
+	while ((host = next_host_state(nlm_server_hosts, nsm, info)) != NULL) {
+		nlmsvc_free_host_resources(host);
+		nlmsvc_release_host(host);
+	}
+	while ((host = next_host_state(nlm_client_hosts, nsm, info)) != NULL) {
+		nlmclnt_recovery(host);
+		nlmclnt_release_host(host);
+	}
+
+	nsm_release(nsm);
+}
+
+static void nlm_complain_hosts(struct net *net)
+{
+	struct hlist_head *chain;
+	struct nlm_host	*host;
+
+	if (net) {
+		struct lockd_net *ln = net_generic(net, lockd_net_id);
+
+		if (ln->nrhosts == 0)
+			return;
+		pr_warn("lockd: couldn't shutdown host module for net %x!\n",
+			net->ns.inum);
+		dprintk("lockd: %lu hosts left in net %x:\n", ln->nrhosts,
+			net->ns.inum);
+	} else {
+		if (nrhosts == 0)
+			return;
+		printk(KERN_WARNING "lockd: couldn't shutdown host module!\n");
+		dprintk("lockd: %lu hosts left:\n", nrhosts);
+	}
+
+	for_each_host(host, chain, nlm_server_hosts) {
+		if (net && host->net != net)
+			continue;
+		dprintk("       %s (cnt %d use %d exp %ld net %x)\n",
+			host->h_name, refcount_read(&host->h_count),
+			host->h_inuse, host->h_expires, host->net->ns.inum);
+	}
+}
+
+void
+nlm_shutdown_hosts_net(struct net *net)
+{
+	struct hlist_head *chain;
+	struct nlm_host	*host;
+
+	mutex_lock(&nlm_host_mutex);
+
+	/* First, make all hosts eligible for gc */
+	dprintk("lockd: nuking all hosts in net %x...\n",
+		net ? net->ns.inum : 0);
+	for_each_host(host, chain, nlm_server_hosts) {
+		if (net && host->net != net)
+			continue;
+		host->h_expires = jiffies - 1;
+		if (host->h_rpcclnt) {
+			rpc_shutdown_client(host->h_rpcclnt);
+			host->h_rpcclnt = NULL;
+		}
+	}
+
+	/* Then, perform a garbage collection pass */
+	nlm_gc_hosts(net);
+	nlm_complain_hosts(net);
+	mutex_unlock(&nlm_host_mutex);
+}
+
+/*
+ * Shut down the hosts module.
+ * Note that this routine is called only at server shutdown time.
+ */
+void
+nlm_shutdown_hosts(void)
+{
+	dprintk("lockd: shutting down host module\n");
+	nlm_shutdown_hosts_net(NULL);
+}
+
+/*
+ * Garbage collect any unused NLM hosts.
+ * This GC combines reference counting for async operations with
+ * mark & sweep for resources held by remote clients.
+ */
+static void
+nlm_gc_hosts(struct net *net)
+{
+	struct hlist_head *chain;
+	struct hlist_node *next;
+	struct nlm_host	*host;
+
+	dprintk("lockd: host garbage collection for net %x\n",
+		net ? net->ns.inum : 0);
+	for_each_host(host, chain, nlm_server_hosts) {
+		if (net && host->net != net)
+			continue;
+		host->h_inuse = 0;
+	}
+
+	/* Mark all hosts that hold locks, blocks or shares */
+	nlmsvc_mark_resources(net);
+
+	for_each_host_safe(host, next, chain, nlm_server_hosts) {
+		if (net && host->net != net)
+			continue;
+		if (host->h_inuse || time_before(jiffies, host->h_expires)) {
+			dprintk("nlm_gc_hosts skipping %s "
+				"(cnt %d use %d exp %ld net %x)\n",
+				host->h_name, refcount_read(&host->h_count),
+				host->h_inuse, host->h_expires,
+				host->net->ns.inum);
+			continue;
+		}
+		if (refcount_dec_if_one(&host->h_count))
+			nlm_destroy_host_locked(host);
+	}
+
+	if (net) {
+		struct lockd_net *ln = net_generic(net, lockd_net_id);
+
+		ln->next_gc = jiffies + NLM_HOST_COLLECT;
+	}
+}