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, 617 insertions, 0 deletions

diff --git a/drivers/isdn/hardware/mISDN/isdnhdlc.c b/drivers/isdn/hardware/mISDN/isdnhdlc.c
new file mode 100644
index 000000000..985367e67
--- /dev/null
+++ b/drivers/isdn/hardware/mISDN/isdnhdlc.c
@@ -0,0 +1,617 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * isdnhdlc.c  --  General purpose ISDN HDLC decoder.
+ *
+ * Copyright (C)
+ *	2009	Karsten Keil		<keil@b1-systems.de>
+ *	2002	Wolfgang Mües		<wolfgang@iksw-muees.de>
+ *	2001	Frode Isaksen		<fisaksen@bewan.com>
+ *      2001	Kai Germaschewski	<kai.germaschewski@gmx.de>
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/crc-ccitt.h>
+#include <linux/bitrev.h>
+#include "isdnhdlc.h"
+
+/*-------------------------------------------------------------------*/
+
+MODULE_AUTHOR("Wolfgang Mües <wolfgang@iksw-muees.de>, "
+	      "Frode Isaksen <fisaksen@bewan.com>, "
+	      "Kai Germaschewski <kai.germaschewski@gmx.de>");
+MODULE_DESCRIPTION("General purpose ISDN HDLC decoder");
+MODULE_LICENSE("GPL");
+
+/*-------------------------------------------------------------------*/
+
+enum {
+	HDLC_FAST_IDLE, HDLC_GET_FLAG_B0, HDLC_GETFLAG_B1A6, HDLC_GETFLAG_B7,
+	HDLC_GET_DATA, HDLC_FAST_FLAG
+};
+
+enum {
+	HDLC_SEND_DATA, HDLC_SEND_CRC1, HDLC_SEND_FAST_FLAG,
+	HDLC_SEND_FIRST_FLAG, HDLC_SEND_CRC2, HDLC_SEND_CLOSING_FLAG,
+	HDLC_SEND_IDLE1, HDLC_SEND_FAST_IDLE, HDLC_SENDFLAG_B0,
+	HDLC_SENDFLAG_B1A6, HDLC_SENDFLAG_B7, STOPPED, HDLC_SENDFLAG_ONE
+};
+
+void isdnhdlc_rcv_init(struct isdnhdlc_vars *hdlc, u32 features)
+{
+	memset(hdlc, 0, sizeof(struct isdnhdlc_vars));
+	hdlc->state = HDLC_GET_DATA;
+	if (features & HDLC_56KBIT)
+		hdlc->do_adapt56 = 1;
+	if (features & HDLC_BITREVERSE)
+		hdlc->do_bitreverse = 1;
+}
+EXPORT_SYMBOL(isdnhdlc_out_init);
+
+void isdnhdlc_out_init(struct isdnhdlc_vars *hdlc, u32 features)
+{
+	memset(hdlc, 0, sizeof(struct isdnhdlc_vars));
+	if (features & HDLC_DCHANNEL) {
+		hdlc->dchannel = 1;
+		hdlc->state = HDLC_SEND_FIRST_FLAG;
+	} else {
+		hdlc->dchannel = 0;
+		hdlc->state = HDLC_SEND_FAST_FLAG;
+		hdlc->ffvalue = 0x7e;
+	}
+	hdlc->cbin = 0x7e;
+	if (features & HDLC_56KBIT) {
+		hdlc->do_adapt56 = 1;
+		hdlc->state = HDLC_SENDFLAG_B0;
+	} else
+		hdlc->data_bits = 8;
+	if (features & HDLC_BITREVERSE)
+		hdlc->do_bitreverse = 1;
+}
+EXPORT_SYMBOL(isdnhdlc_rcv_init);
+
+static int
+check_frame(struct isdnhdlc_vars *hdlc)
+{
+	int status;
+
+	if (hdlc->dstpos < 2)	/* too small - framing error */
+		status = -HDLC_FRAMING_ERROR;
+	else if (hdlc->crc != 0xf0b8)	/* crc error */
+		status = -HDLC_CRC_ERROR;
+	else {
+		/* remove CRC */
+		hdlc->dstpos -= 2;
+		/* good frame */
+		status = hdlc->dstpos;
+	}
+	return status;
+}
+
+/*
+  isdnhdlc_decode - decodes HDLC frames from a transparent bit stream.
+
+  The source buffer is scanned for valid HDLC frames looking for
+  flags (01111110) to indicate the start of a frame. If the start of
+  the frame is found, the bit stuffing is removed (0 after 5 1's).
+  When a new flag is found, the complete frame has been received
+  and the CRC is checked.
+  If a valid frame is found, the function returns the frame length
+  excluding the CRC with the bit HDLC_END_OF_FRAME set.
+  If the beginning of a valid frame is found, the function returns
+  the length.
+  If a framing error is found (too many 1s and not a flag) the function
+  returns the length with the bit HDLC_FRAMING_ERROR set.
+  If a CRC error is found the function returns the length with the
+  bit HDLC_CRC_ERROR set.
+  If the frame length exceeds the destination buffer size, the function
+  returns the length with the bit HDLC_LENGTH_ERROR set.
+
+  src - source buffer
+  slen - source buffer length
+  count - number of bytes removed (decoded) from the source buffer
+  dst _ destination buffer
+  dsize - destination buffer size
+  returns - number of decoded bytes in the destination buffer and status
+  flag.
+*/
+int isdnhdlc_decode(struct isdnhdlc_vars *hdlc, const u8 *src, int slen,
+		    int *count, u8 *dst, int dsize)
+{
+	int status = 0;
+
+	static const unsigned char fast_flag[] = {
+		0x00, 0x00, 0x00, 0x20, 0x30, 0x38, 0x3c, 0x3e, 0x3f
+	};
+
+	static const unsigned char fast_flag_value[] = {
+		0x00, 0x7e, 0xfc, 0xf9, 0xf3, 0xe7, 0xcf, 0x9f, 0x3f
+	};
+
+	static const unsigned char fast_abort[] = {
+		0x00, 0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff
+	};
+
+#define handle_fast_flag(h)						\
+	do {								\
+		if (h->cbin == fast_flag[h->bit_shift]) {		\
+			h->ffvalue = fast_flag_value[h->bit_shift];	\
+			h->state = HDLC_FAST_FLAG;			\
+			h->ffbit_shift = h->bit_shift;			\
+			h->bit_shift = 1;				\
+		} else {						\
+			h->state = HDLC_GET_DATA;			\
+			h->data_received = 0;				\
+		}							\
+	} while (0)
+
+#define handle_abort(h)						\
+	do {							\
+		h->shift_reg = fast_abort[h->ffbit_shift - 1];	\
+		h->hdlc_bits1 = h->ffbit_shift - 2;		\
+		if (h->hdlc_bits1 < 0)				\
+			h->hdlc_bits1 = 0;			\
+		h->data_bits = h->ffbit_shift - 1;		\
+		h->state = HDLC_GET_DATA;			\
+		h->data_received = 0;				\
+	} while (0)
+
+	*count = slen;
+
+	while (slen > 0) {
+		if (hdlc->bit_shift == 0) {
+			/* the code is for bitreverse streams */
+			if (hdlc->do_bitreverse == 0)
+				hdlc->cbin = bitrev8(*src++);
+			else
+				hdlc->cbin = *src++;
+			slen--;
+			hdlc->bit_shift = 8;
+			if (hdlc->do_adapt56)
+				hdlc->bit_shift--;
+		}
+
+		switch (hdlc->state) {
+		case STOPPED:
+			return 0;
+		case HDLC_FAST_IDLE:
+			if (hdlc->cbin == 0xff) {
+				hdlc->bit_shift = 0;
+				break;
+			}
+			hdlc->state = HDLC_GET_FLAG_B0;
+			hdlc->hdlc_bits1 = 0;
+			hdlc->bit_shift = 8;
+			break;
+		case HDLC_GET_FLAG_B0:
+			if (!(hdlc->cbin & 0x80)) {
+				hdlc->state = HDLC_GETFLAG_B1A6;
+				hdlc->hdlc_bits1 = 0;
+			} else {
+				if ((!hdlc->do_adapt56) &&
+				    (++hdlc->hdlc_bits1 >= 8) &&
+				    (hdlc->bit_shift == 1))
+					hdlc->state = HDLC_FAST_IDLE;
+			}
+			hdlc->cbin <<= 1;
+			hdlc->bit_shift--;
+			break;
+		case HDLC_GETFLAG_B1A6:
+			if (hdlc->cbin & 0x80) {
+				hdlc->hdlc_bits1++;
+				if (hdlc->hdlc_bits1 == 6)
+					hdlc->state = HDLC_GETFLAG_B7;
+			} else
+				hdlc->hdlc_bits1 = 0;
+			hdlc->cbin <<= 1;
+			hdlc->bit_shift--;
+			break;
+		case HDLC_GETFLAG_B7:
+			if (hdlc->cbin & 0x80) {
+				hdlc->state = HDLC_GET_FLAG_B0;
+			} else {
+				hdlc->state = HDLC_GET_DATA;
+				hdlc->crc = 0xffff;
+				hdlc->shift_reg = 0;
+				hdlc->hdlc_bits1 = 0;
+				hdlc->data_bits = 0;
+				hdlc->data_received = 0;
+			}
+			hdlc->cbin <<= 1;
+			hdlc->bit_shift--;
+			break;
+		case HDLC_GET_DATA:
+			if (hdlc->cbin & 0x80) {
+				hdlc->hdlc_bits1++;
+				switch (hdlc->hdlc_bits1) {
+				case 6:
+					break;
+				case 7:
+					if (hdlc->data_received)
+						/* bad frame */
+						status = -HDLC_FRAMING_ERROR;
+					if (!hdlc->do_adapt56) {
+						if (hdlc->cbin == fast_abort
+						    [hdlc->bit_shift + 1]) {
+							hdlc->state =
+								HDLC_FAST_IDLE;
+							hdlc->bit_shift = 1;
+							break;
+						}
+					} else
+						hdlc->state = HDLC_GET_FLAG_B0;
+					break;
+				default:
+					hdlc->shift_reg >>= 1;
+					hdlc->shift_reg |= 0x80;
+					hdlc->data_bits++;
+					break;
+				}
+			} else {
+				switch (hdlc->hdlc_bits1) {
+				case 5:
+					break;
+				case 6:
+					if (hdlc->data_received)
+						status = check_frame(hdlc);
+					hdlc->crc = 0xffff;
+					hdlc->shift_reg = 0;
+					hdlc->data_bits = 0;
+					if (!hdlc->do_adapt56)
+						handle_fast_flag(hdlc);
+					else {
+						hdlc->state = HDLC_GET_DATA;
+						hdlc->data_received = 0;
+					}
+					break;
+				default:
+					hdlc->shift_reg >>= 1;
+					hdlc->data_bits++;
+					break;
+				}
+				hdlc->hdlc_bits1 = 0;
+			}
+			if (status) {
+				hdlc->dstpos = 0;
+				*count -= slen;
+				hdlc->cbin <<= 1;
+				hdlc->bit_shift--;
+				return status;
+			}
+			if (hdlc->data_bits == 8) {
+				hdlc->data_bits = 0;
+				hdlc->data_received = 1;
+				hdlc->crc = crc_ccitt_byte(hdlc->crc,
+							   hdlc->shift_reg);
+
+				/* good byte received */
+				if (hdlc->dstpos < dsize)
+					dst[hdlc->dstpos++] = hdlc->shift_reg;
+				else {
+					/* frame too long */
+					status = -HDLC_LENGTH_ERROR;
+					hdlc->dstpos = 0;
+				}
+			}
+			hdlc->cbin <<= 1;
+			hdlc->bit_shift--;
+			break;
+		case HDLC_FAST_FLAG:
+			if (hdlc->cbin == hdlc->ffvalue) {
+				hdlc->bit_shift = 0;
+				break;
+			} else {
+				if (hdlc->cbin == 0xff) {
+					hdlc->state = HDLC_FAST_IDLE;
+					hdlc->bit_shift = 0;
+				} else if (hdlc->ffbit_shift == 8) {
+					hdlc->state = HDLC_GETFLAG_B7;
+					break;
+				} else
+					handle_abort(hdlc);
+			}
+			break;
+		default:
+			break;
+		}
+	}
+	*count -= slen;
+	return 0;
+}
+EXPORT_SYMBOL(isdnhdlc_decode);
+/*
+  isdnhdlc_encode - encodes HDLC frames to a transparent bit stream.
+
+  The bit stream starts with a beginning flag (01111110). After
+  that each byte is added to the bit stream with bit stuffing added
+  (0 after 5 1's).
+  When the last byte has been removed from the source buffer, the
+  CRC (2 bytes is added) and the frame terminates with the ending flag.
+  For the dchannel, the idle character (all 1's) is also added at the end.
+  If this function is called with empty source buffer (slen=0), flags or
+  idle character will be generated.
+
+  src - source buffer
+  slen - source buffer length
+  count - number of bytes removed (encoded) from source buffer
+  dst _ destination buffer
+  dsize - destination buffer size
+  returns - number of encoded bytes in the destination buffer
+*/
+int isdnhdlc_encode(struct isdnhdlc_vars *hdlc, const u8 *src, u16 slen,
+		    int *count, u8 *dst, int dsize)
+{
+	static const unsigned char xfast_flag_value[] = {
+		0x7e, 0x3f, 0x9f, 0xcf, 0xe7, 0xf3, 0xf9, 0xfc, 0x7e
+	};
+
+	int len = 0;
+
+	*count = slen;
+
+	/* special handling for one byte frames */
+	if ((slen == 1) && (hdlc->state == HDLC_SEND_FAST_FLAG))
+		hdlc->state = HDLC_SENDFLAG_ONE;
+	while (dsize > 0) {
+		if (hdlc->bit_shift == 0) {
+			if (slen && !hdlc->do_closing) {
+				hdlc->shift_reg = *src++;
+				slen--;
+				if (slen == 0)
+					/* closing sequence, CRC + flag(s) */
+					hdlc->do_closing = 1;
+				hdlc->bit_shift = 8;
+			} else {
+				if (hdlc->state == HDLC_SEND_DATA) {
+					if (hdlc->data_received) {
+						hdlc->state = HDLC_SEND_CRC1;
+						hdlc->crc ^= 0xffff;
+						hdlc->bit_shift = 8;
+						hdlc->shift_reg =
+							hdlc->crc & 0xff;
+					} else if (!hdlc->do_adapt56)
+						hdlc->state =
+							HDLC_SEND_FAST_FLAG;
+					else
+						hdlc->state =
+							HDLC_SENDFLAG_B0;
+				}
+
+			}
+		}
+
+		switch (hdlc->state) {
+		case STOPPED:
+			while (dsize--)
+				*dst++ = 0xff;
+			return dsize;
+		case HDLC_SEND_FAST_FLAG:
+			hdlc->do_closing = 0;
+			if (slen == 0) {
+				/* the code is for bitreverse streams */
+				if (hdlc->do_bitreverse == 0)
+					*dst++ = bitrev8(hdlc->ffvalue);
+				else
+					*dst++ = hdlc->ffvalue;
+				len++;
+				dsize--;
+				break;
+			}
+			fallthrough;
+		case HDLC_SENDFLAG_ONE:
+			if (hdlc->bit_shift == 8) {
+				hdlc->cbin = hdlc->ffvalue >>
+					(8 - hdlc->data_bits);
+				hdlc->state = HDLC_SEND_DATA;
+				hdlc->crc = 0xffff;
+				hdlc->hdlc_bits1 = 0;
+				hdlc->data_received = 1;
+			}
+			break;
+		case HDLC_SENDFLAG_B0:
+			hdlc->do_closing = 0;
+			hdlc->cbin <<= 1;
+			hdlc->data_bits++;
+			hdlc->hdlc_bits1 = 0;
+			hdlc->state = HDLC_SENDFLAG_B1A6;
+			break;
+		case HDLC_SENDFLAG_B1A6:
+			hdlc->cbin <<= 1;
+			hdlc->data_bits++;
+			hdlc->cbin++;
+			if (++hdlc->hdlc_bits1 == 6)
+				hdlc->state = HDLC_SENDFLAG_B7;
+			break;
+		case HDLC_SENDFLAG_B7:
+			hdlc->cbin <<= 1;
+			hdlc->data_bits++;
+			if (slen == 0) {
+				hdlc->state = HDLC_SENDFLAG_B0;
+				break;
+			}
+			if (hdlc->bit_shift == 8) {
+				hdlc->state = HDLC_SEND_DATA;
+				hdlc->crc = 0xffff;
+				hdlc->hdlc_bits1 = 0;
+				hdlc->data_received = 1;
+			}
+			break;
+		case HDLC_SEND_FIRST_FLAG:
+			hdlc->data_received = 1;
+			if (hdlc->data_bits == 8) {
+				hdlc->state = HDLC_SEND_DATA;
+				hdlc->crc = 0xffff;
+				hdlc->hdlc_bits1 = 0;
+				break;
+			}
+			hdlc->cbin <<= 1;
+			hdlc->data_bits++;
+			if (hdlc->shift_reg & 0x01)
+				hdlc->cbin++;
+			hdlc->shift_reg >>= 1;
+			hdlc->bit_shift--;
+			if (hdlc->bit_shift == 0) {
+				hdlc->state = HDLC_SEND_DATA;
+				hdlc->crc = 0xffff;
+				hdlc->hdlc_bits1 = 0;
+			}
+			break;
+		case HDLC_SEND_DATA:
+			hdlc->cbin <<= 1;
+			hdlc->data_bits++;
+			if (hdlc->hdlc_bits1 == 5) {
+				hdlc->hdlc_bits1 = 0;
+				break;
+			}
+			if (hdlc->bit_shift == 8)
+				hdlc->crc = crc_ccitt_byte(hdlc->crc,
+							   hdlc->shift_reg);
+			if (hdlc->shift_reg & 0x01) {
+				hdlc->hdlc_bits1++;
+				hdlc->cbin++;
+				hdlc->shift_reg >>= 1;
+				hdlc->bit_shift--;
+			} else {
+				hdlc->hdlc_bits1 = 0;
+				hdlc->shift_reg >>= 1;
+				hdlc->bit_shift--;
+			}
+			break;
+		case HDLC_SEND_CRC1:
+			hdlc->cbin <<= 1;
+			hdlc->data_bits++;
+			if (hdlc->hdlc_bits1 == 5) {
+				hdlc->hdlc_bits1 = 0;
+				break;
+			}
+			if (hdlc->shift_reg & 0x01) {
+				hdlc->hdlc_bits1++;
+				hdlc->cbin++;
+				hdlc->shift_reg >>= 1;
+				hdlc->bit_shift--;
+			} else {
+				hdlc->hdlc_bits1 = 0;
+				hdlc->shift_reg >>= 1;
+				hdlc->bit_shift--;
+			}
+			if (hdlc->bit_shift == 0) {
+				hdlc->shift_reg = (hdlc->crc >> 8);
+				hdlc->state = HDLC_SEND_CRC2;
+				hdlc->bit_shift = 8;
+			}
+			break;
+		case HDLC_SEND_CRC2:
+			hdlc->cbin <<= 1;
+			hdlc->data_bits++;
+			if (hdlc->hdlc_bits1 == 5) {
+				hdlc->hdlc_bits1 = 0;
+				break;
+			}
+			if (hdlc->shift_reg & 0x01) {
+				hdlc->hdlc_bits1++;
+				hdlc->cbin++;
+				hdlc->shift_reg >>= 1;
+				hdlc->bit_shift--;
+			} else {
+				hdlc->hdlc_bits1 = 0;
+				hdlc->shift_reg >>= 1;
+				hdlc->bit_shift--;
+			}
+			if (hdlc->bit_shift == 0) {
+				hdlc->shift_reg = 0x7e;
+				hdlc->state = HDLC_SEND_CLOSING_FLAG;
+				hdlc->bit_shift = 8;
+			}
+			break;
+		case HDLC_SEND_CLOSING_FLAG:
+			hdlc->cbin <<= 1;
+			hdlc->data_bits++;
+			if (hdlc->hdlc_bits1 == 5) {
+				hdlc->hdlc_bits1 = 0;
+				break;
+			}
+			if (hdlc->shift_reg & 0x01)
+				hdlc->cbin++;
+			hdlc->shift_reg >>= 1;
+			hdlc->bit_shift--;
+			if (hdlc->bit_shift == 0) {
+				hdlc->ffvalue =
+					xfast_flag_value[hdlc->data_bits];
+				if (hdlc->dchannel) {
+					hdlc->ffvalue = 0x7e;
+					hdlc->state = HDLC_SEND_IDLE1;
+					hdlc->bit_shift = 8-hdlc->data_bits;
+					if (hdlc->bit_shift == 0)
+						hdlc->state =
+							HDLC_SEND_FAST_IDLE;
+				} else {
+					if (!hdlc->do_adapt56) {
+						hdlc->state =
+							HDLC_SEND_FAST_FLAG;
+						hdlc->data_received = 0;
+					} else {
+						hdlc->state = HDLC_SENDFLAG_B0;
+						hdlc->data_received = 0;
+					}
+					/* Finished this frame, send flags */
+					if (dsize > 1)
+						dsize = 1;
+				}
+			}
+			break;
+		case HDLC_SEND_IDLE1:
+			hdlc->do_closing = 0;
+			hdlc->cbin <<= 1;
+			hdlc->cbin++;
+			hdlc->data_bits++;
+			hdlc->bit_shift--;
+			if (hdlc->bit_shift == 0) {
+				hdlc->state = HDLC_SEND_FAST_IDLE;
+				hdlc->bit_shift = 0;
+			}
+			break;
+		case HDLC_SEND_FAST_IDLE:
+			hdlc->do_closing = 0;
+			hdlc->cbin = 0xff;
+			hdlc->data_bits = 8;
+			if (hdlc->bit_shift == 8) {
+				hdlc->cbin = 0x7e;
+				hdlc->state = HDLC_SEND_FIRST_FLAG;
+			} else {
+				/* the code is for bitreverse streams */
+				if (hdlc->do_bitreverse == 0)
+					*dst++ = bitrev8(hdlc->cbin);
+				else
+					*dst++ = hdlc->cbin;
+				hdlc->bit_shift = 0;
+				hdlc->data_bits = 0;
+				len++;
+				dsize = 0;
+			}
+			break;
+		default:
+			break;
+		}
+		if (hdlc->do_adapt56) {
+			if (hdlc->data_bits == 7) {
+				hdlc->cbin <<= 1;
+				hdlc->cbin++;
+				hdlc->data_bits++;
+			}
+		}
+		if (hdlc->data_bits == 8) {
+			/* the code is for bitreverse streams */
+			if (hdlc->do_bitreverse == 0)
+				*dst++ = bitrev8(hdlc->cbin);
+			else
+				*dst++ = hdlc->cbin;
+			hdlc->data_bits = 0;
+			len++;
+			dsize--;
+		}
+	}
+	*count -= slen;
+
+	return len;
+}
+EXPORT_SYMBOL(isdnhdlc_encode);