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, 660 insertions, 0 deletions

diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c
new file mode 100644
index 000000000..caf6355b1
--- /dev/null
+++ b/fs/nfsd/nfsxdr.c
@@ -0,0 +1,660 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * XDR support for nfsd
+ *
+ * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include "vfs.h"
+#include "xdr.h"
+#include "auth.h"
+
+/*
+ * Mapping of S_IF* types to NFS file types
+ */
+static const u32 nfs_ftypes[] = {
+	NFNON,  NFCHR,  NFCHR, NFBAD,
+	NFDIR,  NFBAD,  NFBLK, NFBAD,
+	NFREG,  NFBAD,  NFLNK, NFBAD,
+	NFSOCK, NFBAD,  NFLNK, NFBAD,
+};
+
+
+/*
+ * Basic NFSv2 data types (RFC 1094 Section 2.3)
+ */
+
+/**
+ * svcxdr_encode_stat - Encode an NFSv2 status code
+ * @xdr: XDR stream
+ * @status: status value to encode
+ *
+ * Return values:
+ *   %false: Send buffer space was exhausted
+ *   %true: Success
+ */
+bool
+svcxdr_encode_stat(struct xdr_stream *xdr, __be32 status)
+{
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, sizeof(status));
+	if (!p)
+		return false;
+	*p = status;
+
+	return true;
+}
+
+/**
+ * svcxdr_decode_fhandle - Decode an NFSv2 file handle
+ * @xdr: XDR stream positioned at an encoded NFSv2 FH
+ * @fhp: OUT: filled-in server file handle
+ *
+ * Return values:
+ *  %false: The encoded file handle was not valid
+ *  %true: @fhp has been initialized
+ */
+bool
+svcxdr_decode_fhandle(struct xdr_stream *xdr, struct svc_fh *fhp)
+{
+	__be32 *p;
+
+	p = xdr_inline_decode(xdr, NFS_FHSIZE);
+	if (!p)
+		return false;
+	fh_init(fhp, NFS_FHSIZE);
+	memcpy(&fhp->fh_handle.fh_raw, p, NFS_FHSIZE);
+	fhp->fh_handle.fh_size = NFS_FHSIZE;
+
+	return true;
+}
+
+static bool
+svcxdr_encode_fhandle(struct xdr_stream *xdr, const struct svc_fh *fhp)
+{
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, NFS_FHSIZE);
+	if (!p)
+		return false;
+	memcpy(p, &fhp->fh_handle.fh_raw, NFS_FHSIZE);
+
+	return true;
+}
+
+static __be32 *
+encode_timeval(__be32 *p, const struct timespec64 *time)
+{
+	*p++ = cpu_to_be32((u32)time->tv_sec);
+	if (time->tv_nsec)
+		*p++ = cpu_to_be32(time->tv_nsec / NSEC_PER_USEC);
+	else
+		*p++ = xdr_zero;
+	return p;
+}
+
+static bool
+svcxdr_decode_filename(struct xdr_stream *xdr, char **name, unsigned int *len)
+{
+	u32 size, i;
+	__be32 *p;
+	char *c;
+
+	if (xdr_stream_decode_u32(xdr, &size) < 0)
+		return false;
+	if (size == 0 || size > NFS_MAXNAMLEN)
+		return false;
+	p = xdr_inline_decode(xdr, size);
+	if (!p)
+		return false;
+
+	*len = size;
+	*name = (char *)p;
+	for (i = 0, c = *name; i < size; i++, c++)
+		if (*c == '\0' || *c == '/')
+			return false;
+
+	return true;
+}
+
+static bool
+svcxdr_decode_diropargs(struct xdr_stream *xdr, struct svc_fh *fhp,
+			char **name, unsigned int *len)
+{
+	return svcxdr_decode_fhandle(xdr, fhp) &&
+		svcxdr_decode_filename(xdr, name, len);
+}
+
+static bool
+svcxdr_decode_sattr(struct svc_rqst *rqstp, struct xdr_stream *xdr,
+		    struct iattr *iap)
+{
+	u32 tmp1, tmp2;
+	__be32 *p;
+
+	p = xdr_inline_decode(xdr, XDR_UNIT * 8);
+	if (!p)
+		return false;
+
+	iap->ia_valid = 0;
+
+	/*
+	 * Some Sun clients put 0xffff in the mode field when they
+	 * mean 0xffffffff.
+	 */
+	tmp1 = be32_to_cpup(p++);
+	if (tmp1 != (u32)-1 && tmp1 != 0xffff) {
+		iap->ia_valid |= ATTR_MODE;
+		iap->ia_mode = tmp1;
+	}
+
+	tmp1 = be32_to_cpup(p++);
+	if (tmp1 != (u32)-1) {
+		iap->ia_uid = make_kuid(nfsd_user_namespace(rqstp), tmp1);
+		if (uid_valid(iap->ia_uid))
+			iap->ia_valid |= ATTR_UID;
+	}
+
+	tmp1 = be32_to_cpup(p++);
+	if (tmp1 != (u32)-1) {
+		iap->ia_gid = make_kgid(nfsd_user_namespace(rqstp), tmp1);
+		if (gid_valid(iap->ia_gid))
+			iap->ia_valid |= ATTR_GID;
+	}
+
+	tmp1 = be32_to_cpup(p++);
+	if (tmp1 != (u32)-1) {
+		iap->ia_valid |= ATTR_SIZE;
+		iap->ia_size = tmp1;
+	}
+
+	tmp1 = be32_to_cpup(p++);
+	tmp2 = be32_to_cpup(p++);
+	if (tmp1 != (u32)-1 && tmp2 != (u32)-1) {
+		iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET;
+		iap->ia_atime.tv_sec = tmp1;
+		iap->ia_atime.tv_nsec = tmp2 * NSEC_PER_USEC;
+	}
+
+	tmp1 = be32_to_cpup(p++);
+	tmp2 = be32_to_cpup(p++);
+	if (tmp1 != (u32)-1 && tmp2 != (u32)-1) {
+		iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET;
+		iap->ia_mtime.tv_sec = tmp1;
+		iap->ia_mtime.tv_nsec = tmp2 * NSEC_PER_USEC;
+		/*
+		 * Passing the invalid value useconds=1000000 for mtime
+		 * is a Sun convention for "set both mtime and atime to
+		 * current server time".  It's needed to make permissions
+		 * checks for the "touch" program across v2 mounts to
+		 * Solaris and Irix boxes work correctly. See description of
+		 * sattr in section 6.1 of "NFS Illustrated" by
+		 * Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5
+		 */
+		if (tmp2 == 1000000)
+			iap->ia_valid &= ~(ATTR_ATIME_SET|ATTR_MTIME_SET);
+	}
+
+	return true;
+}
+
+/**
+ * svcxdr_encode_fattr - Encode NFSv2 file attributes
+ * @rqstp: Context of a completed RPC transaction
+ * @xdr: XDR stream
+ * @fhp: File handle to encode
+ * @stat: Attributes to encode
+ *
+ * Return values:
+ *   %false: Send buffer space was exhausted
+ *   %true: Success
+ */
+bool
+svcxdr_encode_fattr(struct svc_rqst *rqstp, struct xdr_stream *xdr,
+		    const struct svc_fh *fhp, const struct kstat *stat)
+{
+	struct user_namespace *userns = nfsd_user_namespace(rqstp);
+	struct dentry *dentry = fhp->fh_dentry;
+	int type = stat->mode & S_IFMT;
+	struct timespec64 time;
+	__be32 *p;
+	u32 fsid;
+
+	p = xdr_reserve_space(xdr, XDR_UNIT * 17);
+	if (!p)
+		return false;
+
+	*p++ = cpu_to_be32(nfs_ftypes[type >> 12]);
+	*p++ = cpu_to_be32((u32)stat->mode);
+	*p++ = cpu_to_be32((u32)stat->nlink);
+	*p++ = cpu_to_be32((u32)from_kuid_munged(userns, stat->uid));
+	*p++ = cpu_to_be32((u32)from_kgid_munged(userns, stat->gid));
+
+	if (S_ISLNK(type) && stat->size > NFS_MAXPATHLEN)
+		*p++ = cpu_to_be32(NFS_MAXPATHLEN);
+	else
+		*p++ = cpu_to_be32((u32) stat->size);
+	*p++ = cpu_to_be32((u32) stat->blksize);
+	if (S_ISCHR(type) || S_ISBLK(type))
+		*p++ = cpu_to_be32(new_encode_dev(stat->rdev));
+	else
+		*p++ = cpu_to_be32(0xffffffff);
+	*p++ = cpu_to_be32((u32)stat->blocks);
+
+	switch (fsid_source(fhp)) {
+	case FSIDSOURCE_FSID:
+		fsid = (u32)fhp->fh_export->ex_fsid;
+		break;
+	case FSIDSOURCE_UUID:
+		fsid = ((u32 *)fhp->fh_export->ex_uuid)[0];
+		fsid ^= ((u32 *)fhp->fh_export->ex_uuid)[1];
+		fsid ^= ((u32 *)fhp->fh_export->ex_uuid)[2];
+		fsid ^= ((u32 *)fhp->fh_export->ex_uuid)[3];
+		break;
+	default:
+		fsid = new_encode_dev(stat->dev);
+		break;
+	}
+	*p++ = cpu_to_be32(fsid);
+
+	*p++ = cpu_to_be32((u32)stat->ino);
+	p = encode_timeval(p, &stat->atime);
+	time = stat->mtime;
+	lease_get_mtime(d_inode(dentry), &time);
+	p = encode_timeval(p, &time);
+	encode_timeval(p, &stat->ctime);
+
+	return true;
+}
+
+/*
+ * XDR decode functions
+ */
+
+bool
+nfssvc_decode_fhandleargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_fhandle *args = rqstp->rq_argp;
+
+	return svcxdr_decode_fhandle(xdr, &args->fh);
+}
+
+bool
+nfssvc_decode_sattrargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_sattrargs *args = rqstp->rq_argp;
+
+	return svcxdr_decode_fhandle(xdr, &args->fh) &&
+		svcxdr_decode_sattr(rqstp, xdr, &args->attrs);
+}
+
+bool
+nfssvc_decode_diropargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_diropargs *args = rqstp->rq_argp;
+
+	return svcxdr_decode_diropargs(xdr, &args->fh, &args->name, &args->len);
+}
+
+bool
+nfssvc_decode_readargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_readargs *args = rqstp->rq_argp;
+	u32 totalcount;
+
+	if (!svcxdr_decode_fhandle(xdr, &args->fh))
+		return false;
+	if (xdr_stream_decode_u32(xdr, &args->offset) < 0)
+		return false;
+	if (xdr_stream_decode_u32(xdr, &args->count) < 0)
+		return false;
+	/* totalcount is ignored */
+	if (xdr_stream_decode_u32(xdr, &totalcount) < 0)
+		return false;
+
+	return true;
+}
+
+bool
+nfssvc_decode_writeargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_writeargs *args = rqstp->rq_argp;
+	u32 beginoffset, totalcount;
+
+	if (!svcxdr_decode_fhandle(xdr, &args->fh))
+		return false;
+	/* beginoffset is ignored */
+	if (xdr_stream_decode_u32(xdr, &beginoffset) < 0)
+		return false;
+	if (xdr_stream_decode_u32(xdr, &args->offset) < 0)
+		return false;
+	/* totalcount is ignored */
+	if (xdr_stream_decode_u32(xdr, &totalcount) < 0)
+		return false;
+
+	/* opaque data */
+	if (xdr_stream_decode_u32(xdr, &args->len) < 0)
+		return false;
+	if (args->len > NFSSVC_MAXBLKSIZE_V2)
+		return false;
+
+	return xdr_stream_subsegment(xdr, &args->payload, args->len);
+}
+
+bool
+nfssvc_decode_createargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_createargs *args = rqstp->rq_argp;
+
+	return svcxdr_decode_diropargs(xdr, &args->fh,
+				       &args->name, &args->len) &&
+		svcxdr_decode_sattr(rqstp, xdr, &args->attrs);
+}
+
+bool
+nfssvc_decode_renameargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_renameargs *args = rqstp->rq_argp;
+
+	return svcxdr_decode_diropargs(xdr, &args->ffh,
+				       &args->fname, &args->flen) &&
+		svcxdr_decode_diropargs(xdr, &args->tfh,
+					&args->tname, &args->tlen);
+}
+
+bool
+nfssvc_decode_linkargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_linkargs *args = rqstp->rq_argp;
+
+	return svcxdr_decode_fhandle(xdr, &args->ffh) &&
+		svcxdr_decode_diropargs(xdr, &args->tfh,
+					&args->tname, &args->tlen);
+}
+
+bool
+nfssvc_decode_symlinkargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_symlinkargs *args = rqstp->rq_argp;
+	struct kvec *head = rqstp->rq_arg.head;
+
+	if (!svcxdr_decode_diropargs(xdr, &args->ffh, &args->fname, &args->flen))
+		return false;
+	if (xdr_stream_decode_u32(xdr, &args->tlen) < 0)
+		return false;
+	if (args->tlen == 0)
+		return false;
+
+	args->first.iov_len = head->iov_len - xdr_stream_pos(xdr);
+	args->first.iov_base = xdr_inline_decode(xdr, args->tlen);
+	if (!args->first.iov_base)
+		return false;
+	return svcxdr_decode_sattr(rqstp, xdr, &args->attrs);
+}
+
+bool
+nfssvc_decode_readdirargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_readdirargs *args = rqstp->rq_argp;
+
+	if (!svcxdr_decode_fhandle(xdr, &args->fh))
+		return false;
+	if (xdr_stream_decode_u32(xdr, &args->cookie) < 0)
+		return false;
+	if (xdr_stream_decode_u32(xdr, &args->count) < 0)
+		return false;
+
+	return true;
+}
+
+/*
+ * XDR encode functions
+ */
+
+bool
+nfssvc_encode_statres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_stat *resp = rqstp->rq_resp;
+
+	return svcxdr_encode_stat(xdr, resp->status);
+}
+
+bool
+nfssvc_encode_attrstatres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_attrstat *resp = rqstp->rq_resp;
+
+	if (!svcxdr_encode_stat(xdr, resp->status))
+		return false;
+	switch (resp->status) {
+	case nfs_ok:
+		if (!svcxdr_encode_fattr(rqstp, xdr, &resp->fh, &resp->stat))
+			return false;
+		break;
+	}
+
+	return true;
+}
+
+bool
+nfssvc_encode_diropres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_diropres *resp = rqstp->rq_resp;
+
+	if (!svcxdr_encode_stat(xdr, resp->status))
+		return false;
+	switch (resp->status) {
+	case nfs_ok:
+		if (!svcxdr_encode_fhandle(xdr, &resp->fh))
+			return false;
+		if (!svcxdr_encode_fattr(rqstp, xdr, &resp->fh, &resp->stat))
+			return false;
+		break;
+	}
+
+	return true;
+}
+
+bool
+nfssvc_encode_readlinkres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_readlinkres *resp = rqstp->rq_resp;
+	struct kvec *head = rqstp->rq_res.head;
+
+	if (!svcxdr_encode_stat(xdr, resp->status))
+		return false;
+	switch (resp->status) {
+	case nfs_ok:
+		if (xdr_stream_encode_u32(xdr, resp->len) < 0)
+			return false;
+		xdr_write_pages(xdr, &resp->page, 0, resp->len);
+		if (svc_encode_result_payload(rqstp, head->iov_len, resp->len) < 0)
+			return false;
+		break;
+	}
+
+	return true;
+}
+
+bool
+nfssvc_encode_readres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_readres *resp = rqstp->rq_resp;
+	struct kvec *head = rqstp->rq_res.head;
+
+	if (!svcxdr_encode_stat(xdr, resp->status))
+		return false;
+	switch (resp->status) {
+	case nfs_ok:
+		if (!svcxdr_encode_fattr(rqstp, xdr, &resp->fh, &resp->stat))
+			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);
+		if (svc_encode_result_payload(rqstp, head->iov_len, resp->count) < 0)
+			return false;
+		break;
+	}
+
+	return true;
+}
+
+bool
+nfssvc_encode_readdirres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_readdirres *resp = rqstp->rq_resp;
+	struct xdr_buf *dirlist = &resp->dirlist;
+
+	if (!svcxdr_encode_stat(xdr, resp->status))
+		return false;
+	switch (resp->status) {
+	case nfs_ok:
+		xdr_write_pages(xdr, dirlist->pages, 0, dirlist->len);
+		/* no more entries */
+		if (xdr_stream_encode_item_absent(xdr) < 0)
+			return false;
+		if (xdr_stream_encode_bool(xdr, resp->common.err == nfserr_eof) < 0)
+			return false;
+		break;
+	}
+
+	return true;
+}
+
+bool
+nfssvc_encode_statfsres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+{
+	struct nfsd_statfsres *resp = rqstp->rq_resp;
+	struct kstatfs	*stat = &resp->stats;
+	__be32 *p;
+
+	if (!svcxdr_encode_stat(xdr, resp->status))
+		return false;
+	switch (resp->status) {
+	case nfs_ok:
+		p = xdr_reserve_space(xdr, XDR_UNIT * 5);
+		if (!p)
+			return false;
+		*p++ = cpu_to_be32(NFSSVC_MAXBLKSIZE_V2);
+		*p++ = cpu_to_be32(stat->f_bsize);
+		*p++ = cpu_to_be32(stat->f_blocks);
+		*p++ = cpu_to_be32(stat->f_bfree);
+		*p = cpu_to_be32(stat->f_bavail);
+		break;
+	}
+
+	return true;
+}
+
+/**
+ * nfssvc_encode_nfscookie - Encode a directory offset cookie
+ * @resp: readdir result context
+ * @offset: offset cookie to encode
+ *
+ * The buffer space for the offset cookie has already been reserved
+ * by svcxdr_encode_entry_common().
+ */
+void nfssvc_encode_nfscookie(struct nfsd_readdirres *resp, u32 offset)
+{
+	__be32 cookie = cpu_to_be32(offset);
+
+	if (!resp->cookie_offset)
+		return;
+
+	write_bytes_to_xdr_buf(&resp->dirlist, resp->cookie_offset, &cookie,
+			       sizeof(cookie));
+	resp->cookie_offset = 0;
+}
+
+static bool
+svcxdr_encode_entry_common(struct nfsd_readdirres *resp, const char *name,
+			   int namlen, loff_t offset, u64 ino)
+{
+	struct xdr_buf *dirlist = &resp->dirlist;
+	struct xdr_stream *xdr = &resp->xdr;
+
+	if (xdr_stream_encode_item_present(xdr) < 0)
+		return false;
+	/* fileid */
+	if (xdr_stream_encode_u32(xdr, (u32)ino) < 0)
+		return false;
+	/* name */
+	if (xdr_stream_encode_opaque(xdr, name, min(namlen, NFS2_MAXNAMLEN)) < 0)
+		return false;
+	/* cookie */
+	resp->cookie_offset = dirlist->len;
+	if (xdr_stream_encode_u32(xdr, ~0U) < 0)
+		return false;
+
+	return true;
+}
+
+/**
+ * nfssvc_encode_entry - encode one NFSv2 READDIR entry
+ * @data: directory context
+ * @name: name of the object to be encoded
+ * @namlen: length of that name, in bytes
+ * @offset: the offset of the previous entry
+ * @ino: the fileid of this entry
+ * @d_type: unused
+ *
+ * Return values:
+ *   %0: Entry was successfully encoded.
+ *   %-EINVAL: An encoding problem occured, secondary status code in resp->common.err
+ *
+ * On exit, the following fields are updated:
+ *   - resp->xdr
+ *   - resp->common.err
+ *   - resp->cookie_offset
+ */
+int nfssvc_encode_entry(void *data, const char *name, int namlen,
+			loff_t offset, u64 ino, unsigned int d_type)
+{
+	struct readdir_cd *ccd = data;
+	struct nfsd_readdirres *resp = container_of(ccd,
+						    struct nfsd_readdirres,
+						    common);
+	unsigned int starting_length = resp->dirlist.len;
+
+	/* The offset cookie for the previous entry */
+	nfssvc_encode_nfscookie(resp, offset);
+
+	if (!svcxdr_encode_entry_common(resp, name, namlen, offset, ino))
+		goto out_toosmall;
+
+	xdr_commit_encode(&resp->xdr);
+	resp->common.err = nfs_ok;
+	return 0;
+
+out_toosmall:
+	resp->cookie_offset = 0;
+	resp->common.err = nfserr_toosmall;
+	resp->dirlist.len = starting_length;
+	return -EINVAL;
+}
+
+/*
+ * XDR release functions
+ */
+void nfssvc_release_attrstat(struct svc_rqst *rqstp)
+{
+	struct nfsd_attrstat *resp = rqstp->rq_resp;
+
+	fh_put(&resp->fh);
+}
+
+void nfssvc_release_diropres(struct svc_rqst *rqstp)
+{
+	struct nfsd_diropres *resp = rqstp->rq_resp;
+
+	fh_put(&resp->fh);
+}
+
+void nfssvc_release_readres(struct svc_rqst *rqstp)
+{
+	struct nfsd_readres *resp = rqstp->rq_resp;
+
+	fh_put(&resp->fh);
+}