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, 688 insertions, 0 deletions

diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
new file mode 100644
index 000000000..0a0e984e5
--- /dev/null
+++ b/drivers/misc/mei/interrupt.c
@@ -0,0 +1,688 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2003-2018, Intel Corporation. All rights reserved.
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ */
+
+#include <linux/export.h>
+#include <linux/kthread.h>
+#include <linux/interrupt.h>
+#include <linux/fs.h>
+#include <linux/jiffies.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/mei.h>
+
+#include "mei_dev.h"
+#include "hbm.h"
+#include "client.h"
+
+
+/**
+ * mei_irq_compl_handler - dispatch complete handlers
+ *	for the completed callbacks
+ *
+ * @dev: mei device
+ * @cmpl_list: list of completed cbs
+ */
+void mei_irq_compl_handler(struct mei_device *dev, struct list_head *cmpl_list)
+{
+	struct mei_cl_cb *cb, *next;
+	struct mei_cl *cl;
+
+	list_for_each_entry_safe(cb, next, cmpl_list, list) {
+		cl = cb->cl;
+		list_del_init(&cb->list);
+
+		dev_dbg(dev->dev, "completing call back.\n");
+		mei_cl_complete(cl, cb);
+	}
+}
+EXPORT_SYMBOL_GPL(mei_irq_compl_handler);
+
+/**
+ * mei_cl_hbm_equal - check if hbm is addressed to the client
+ *
+ * @cl: host client
+ * @mei_hdr: header of mei client message
+ *
+ * Return: true if matches, false otherwise
+ */
+static inline int mei_cl_hbm_equal(struct mei_cl *cl,
+			struct mei_msg_hdr *mei_hdr)
+{
+	return  mei_cl_host_addr(cl) == mei_hdr->host_addr &&
+		mei_cl_me_id(cl) == mei_hdr->me_addr;
+}
+
+/**
+ * mei_irq_discard_msg  - discard received message
+ *
+ * @dev: mei device
+ * @hdr: message header
+ * @discard_len: the length of the message to discard (excluding header)
+ */
+static void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr,
+				size_t discard_len)
+{
+	if (hdr->dma_ring) {
+		mei_dma_ring_read(dev, NULL,
+				  hdr->extension[dev->rd_msg_hdr_count - 2]);
+		discard_len = 0;
+	}
+	/*
+	 * no need to check for size as it is guarantied
+	 * that length fits into rd_msg_buf
+	 */
+	mei_read_slots(dev, dev->rd_msg_buf, discard_len);
+	dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
+		MEI_HDR_PRM(hdr));
+}
+
+/**
+ * mei_cl_irq_read_msg - process client message
+ *
+ * @cl: reading client
+ * @mei_hdr: header of mei client message
+ * @meta: extend meta header
+ * @cmpl_list: completion list
+ *
+ * Return: always 0
+ */
+static int mei_cl_irq_read_msg(struct mei_cl *cl,
+			       struct mei_msg_hdr *mei_hdr,
+			       struct mei_ext_meta_hdr *meta,
+			       struct list_head *cmpl_list)
+{
+	struct mei_device *dev = cl->dev;
+	struct mei_cl_cb *cb;
+
+	struct mei_ext_hdr_vtag *vtag_hdr = NULL;
+	struct mei_ext_hdr_gsc_f2h *gsc_f2h = NULL;
+
+	size_t buf_sz;
+	u32 length;
+	u32 ext_len;
+
+	length = mei_hdr->length;
+	ext_len = 0;
+	if (mei_hdr->extended) {
+		ext_len = sizeof(*meta) + mei_slots2data(meta->size);
+		length -= ext_len;
+	}
+
+	cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
+	if (!cb) {
+		if (!mei_cl_is_fixed_address(cl)) {
+			cl_err(dev, cl, "pending read cb not found\n");
+			goto discard;
+		}
+		cb = mei_cl_alloc_cb(cl, mei_cl_mtu(cl), MEI_FOP_READ, cl->fp);
+		if (!cb)
+			goto discard;
+		list_add_tail(&cb->list, &cl->rd_pending);
+	}
+
+	if (mei_hdr->extended) {
+		struct mei_ext_hdr *ext = mei_ext_begin(meta);
+		do {
+			switch (ext->type) {
+			case MEI_EXT_HDR_VTAG:
+				vtag_hdr = (struct mei_ext_hdr_vtag *)ext;
+				break;
+			case MEI_EXT_HDR_GSC:
+				gsc_f2h = (struct mei_ext_hdr_gsc_f2h *)ext;
+				cb->ext_hdr = kzalloc(sizeof(*gsc_f2h), GFP_KERNEL);
+				if (!cb->ext_hdr) {
+					cb->status = -ENOMEM;
+					goto discard;
+				}
+				break;
+			case MEI_EXT_HDR_NONE:
+				fallthrough;
+			default:
+				cl_err(dev, cl, "unknown extended header\n");
+				cb->status = -EPROTO;
+				break;
+			}
+
+			ext = mei_ext_next(ext);
+		} while (!mei_ext_last(meta, ext));
+
+		if (!vtag_hdr && !gsc_f2h) {
+			cl_dbg(dev, cl, "no vtag or gsc found in extended header.\n");
+			cb->status = -EPROTO;
+			goto discard;
+		}
+	}
+
+	if (vtag_hdr) {
+		cl_dbg(dev, cl, "vtag: %d\n", vtag_hdr->vtag);
+		if (cb->vtag && cb->vtag != vtag_hdr->vtag) {
+			cl_err(dev, cl, "mismatched tag: %d != %d\n",
+			       cb->vtag, vtag_hdr->vtag);
+			cb->status = -EPROTO;
+			goto discard;
+		}
+		cb->vtag = vtag_hdr->vtag;
+	}
+
+	if (gsc_f2h) {
+		u32 ext_hdr_len = mei_ext_hdr_len(&gsc_f2h->hdr);
+
+		if (!dev->hbm_f_gsc_supported) {
+			cl_err(dev, cl, "gsc extended header is not supported\n");
+			cb->status = -EPROTO;
+			goto discard;
+		}
+
+		if (length) {
+			cl_err(dev, cl, "no data allowed in cb with gsc\n");
+			cb->status = -EPROTO;
+			goto discard;
+		}
+		if (ext_hdr_len > sizeof(*gsc_f2h)) {
+			cl_err(dev, cl, "gsc extended header is too big %u\n", ext_hdr_len);
+			cb->status = -EPROTO;
+			goto discard;
+		}
+		memcpy(cb->ext_hdr, gsc_f2h, ext_hdr_len);
+	}
+
+	if (!mei_cl_is_connected(cl)) {
+		cl_dbg(dev, cl, "not connected\n");
+		cb->status = -ENODEV;
+		goto discard;
+	}
+
+	if (mei_hdr->dma_ring)
+		length = mei_hdr->extension[mei_data2slots(ext_len)];
+
+	buf_sz = length + cb->buf_idx;
+	/* catch for integer overflow */
+	if (buf_sz < cb->buf_idx) {
+		cl_err(dev, cl, "message is too big len %d idx %zu\n",
+		       length, cb->buf_idx);
+		cb->status = -EMSGSIZE;
+		goto discard;
+	}
+
+	if (cb->buf.size < buf_sz) {
+		cl_dbg(dev, cl, "message overflow. size %zu len %d idx %zu\n",
+			cb->buf.size, length, cb->buf_idx);
+		cb->status = -EMSGSIZE;
+		goto discard;
+	}
+
+	if (mei_hdr->dma_ring) {
+		mei_dma_ring_read(dev, cb->buf.data + cb->buf_idx, length);
+		/*  for DMA read 0 length to generate interrupt to the device */
+		mei_read_slots(dev, cb->buf.data + cb->buf_idx, 0);
+	} else {
+		mei_read_slots(dev, cb->buf.data + cb->buf_idx, length);
+	}
+
+	cb->buf_idx += length;
+
+	if (mei_hdr->msg_complete) {
+		cl_dbg(dev, cl, "completed read length = %zu\n", cb->buf_idx);
+		list_move_tail(&cb->list, cmpl_list);
+	} else {
+		pm_runtime_mark_last_busy(dev->dev);
+		pm_request_autosuspend(dev->dev);
+	}
+
+	return 0;
+
+discard:
+	if (cb)
+		list_move_tail(&cb->list, cmpl_list);
+	mei_irq_discard_msg(dev, mei_hdr, length);
+	return 0;
+}
+
+/**
+ * mei_cl_irq_disconnect_rsp - send disconnection response message
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
+				     struct list_head *cmpl_list)
+{
+	struct mei_device *dev = cl->dev;
+	u32 msg_slots;
+	int slots;
+	int ret;
+
+	msg_slots = mei_hbm2slots(sizeof(struct hbm_client_connect_response));
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if ((u32)slots < msg_slots)
+		return -EMSGSIZE;
+
+	ret = mei_hbm_cl_disconnect_rsp(dev, cl);
+	list_move_tail(&cb->list, cmpl_list);
+
+	return ret;
+}
+
+/**
+ * mei_cl_irq_read - processes client read related operation from the
+ *	interrupt thread context - request for flow control credits
+ *
+ * @cl: client
+ * @cb: callback block.
+ * @cmpl_list: complete list.
+ *
+ * Return: 0, OK; otherwise, error.
+ */
+static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
+			   struct list_head *cmpl_list)
+{
+	struct mei_device *dev = cl->dev;
+	u32 msg_slots;
+	int slots;
+	int ret;
+
+	if (!list_empty(&cl->rd_pending))
+		return 0;
+
+	msg_slots = mei_hbm2slots(sizeof(struct hbm_flow_control));
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if ((u32)slots < msg_slots)
+		return -EMSGSIZE;
+
+	ret = mei_hbm_cl_flow_control_req(dev, cl);
+	if (ret) {
+		cl->status = ret;
+		cb->buf_idx = 0;
+		list_move_tail(&cb->list, cmpl_list);
+		return ret;
+	}
+
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_request_autosuspend(dev->dev);
+
+	list_move_tail(&cb->list, &cl->rd_pending);
+
+	return 0;
+}
+
+static inline bool hdr_is_hbm(struct mei_msg_hdr *mei_hdr)
+{
+	return mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0;
+}
+
+static inline bool hdr_is_fixed(struct mei_msg_hdr *mei_hdr)
+{
+	return mei_hdr->host_addr == 0 && mei_hdr->me_addr != 0;
+}
+
+static inline int hdr_is_valid(u32 msg_hdr)
+{
+	struct mei_msg_hdr *mei_hdr;
+	u32 expected_len = 0;
+
+	mei_hdr = (struct mei_msg_hdr *)&msg_hdr;
+	if (!msg_hdr || mei_hdr->reserved)
+		return -EBADMSG;
+
+	if (mei_hdr->dma_ring)
+		expected_len += MEI_SLOT_SIZE;
+	if (mei_hdr->extended)
+		expected_len += MEI_SLOT_SIZE;
+	if (mei_hdr->length < expected_len)
+		return -EBADMSG;
+
+	return 0;
+}
+
+/**
+ * mei_irq_read_handler - bottom half read routine after ISR to
+ * handle the read processing.
+ *
+ * @dev: the device structure
+ * @cmpl_list: An instance of our list structure
+ * @slots: slots to read.
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_irq_read_handler(struct mei_device *dev,
+			 struct list_head *cmpl_list, s32 *slots)
+{
+	struct mei_msg_hdr *mei_hdr;
+	struct mei_ext_meta_hdr *meta_hdr = NULL;
+	struct mei_cl *cl;
+	int ret;
+	u32 hdr_size_left;
+	u32 hdr_size_ext;
+	int i;
+	int ext_hdr_end;
+
+	if (!dev->rd_msg_hdr[0]) {
+		dev->rd_msg_hdr[0] = mei_read_hdr(dev);
+		dev->rd_msg_hdr_count = 1;
+		(*slots)--;
+		dev_dbg(dev->dev, "slots =%08x.\n", *slots);
+
+		ret = hdr_is_valid(dev->rd_msg_hdr[0]);
+		if (ret) {
+			dev_err(dev->dev, "corrupted message header 0x%08X\n",
+				dev->rd_msg_hdr[0]);
+			goto end;
+		}
+	}
+
+	mei_hdr = (struct mei_msg_hdr *)dev->rd_msg_hdr;
+	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
+
+	if (mei_slots2data(*slots) < mei_hdr->length) {
+		dev_err(dev->dev, "less data available than length=%08x.\n",
+				*slots);
+		/* we can't read the message */
+		ret = -ENODATA;
+		goto end;
+	}
+
+	ext_hdr_end = 1;
+	hdr_size_left = mei_hdr->length;
+
+	if (mei_hdr->extended) {
+		if (!dev->rd_msg_hdr[1]) {
+			dev->rd_msg_hdr[1] = mei_read_hdr(dev);
+			dev->rd_msg_hdr_count++;
+			(*slots)--;
+			dev_dbg(dev->dev, "extended header is %08x\n", dev->rd_msg_hdr[1]);
+		}
+		meta_hdr = ((struct mei_ext_meta_hdr *)&dev->rd_msg_hdr[1]);
+		if (check_add_overflow((u32)sizeof(*meta_hdr),
+				       mei_slots2data(meta_hdr->size),
+				       &hdr_size_ext)) {
+			dev_err(dev->dev, "extended message size too big %d\n",
+				meta_hdr->size);
+			return -EBADMSG;
+		}
+		if (hdr_size_left < hdr_size_ext) {
+			dev_err(dev->dev, "corrupted message header len %d\n",
+				mei_hdr->length);
+			return -EBADMSG;
+		}
+		hdr_size_left -= hdr_size_ext;
+
+		ext_hdr_end = meta_hdr->size + 2;
+		for (i = dev->rd_msg_hdr_count; i < ext_hdr_end; i++) {
+			dev->rd_msg_hdr[i] = mei_read_hdr(dev);
+			dev_dbg(dev->dev, "extended header %d is %08x\n", i,
+				dev->rd_msg_hdr[i]);
+			dev->rd_msg_hdr_count++;
+			(*slots)--;
+		}
+	}
+
+	if (mei_hdr->dma_ring) {
+		if (hdr_size_left != sizeof(dev->rd_msg_hdr[ext_hdr_end])) {
+			dev_err(dev->dev, "corrupted message header len %d\n",
+				mei_hdr->length);
+			return -EBADMSG;
+		}
+
+		dev->rd_msg_hdr[ext_hdr_end] = mei_read_hdr(dev);
+		dev->rd_msg_hdr_count++;
+		(*slots)--;
+		mei_hdr->length -= sizeof(dev->rd_msg_hdr[ext_hdr_end]);
+	}
+
+	/*  HBM message */
+	if (hdr_is_hbm(mei_hdr)) {
+		ret = mei_hbm_dispatch(dev, mei_hdr);
+		if (ret) {
+			dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
+					ret);
+			goto end;
+		}
+		goto reset_slots;
+	}
+
+	/* find recipient cl */
+	list_for_each_entry(cl, &dev->file_list, link) {
+		if (mei_cl_hbm_equal(cl, mei_hdr)) {
+			cl_dbg(dev, cl, "got a message\n");
+			ret = mei_cl_irq_read_msg(cl, mei_hdr, meta_hdr, cmpl_list);
+			goto reset_slots;
+		}
+	}
+
+	/* if no recipient cl was found we assume corrupted header */
+	/* A message for not connected fixed address clients
+	 * should be silently discarded
+	 * On power down client may be force cleaned,
+	 * silently discard such messages
+	 */
+	if (hdr_is_fixed(mei_hdr) ||
+	    dev->dev_state == MEI_DEV_POWER_DOWN) {
+		mei_irq_discard_msg(dev, mei_hdr, mei_hdr->length);
+		ret = 0;
+		goto reset_slots;
+	}
+	dev_err(dev->dev, "no destination client found 0x%08X\n", dev->rd_msg_hdr[0]);
+	ret = -EBADMSG;
+	goto end;
+
+reset_slots:
+	/* reset the number of slots and header */
+	memset(dev->rd_msg_hdr, 0, sizeof(dev->rd_msg_hdr));
+	dev->rd_msg_hdr_count = 0;
+	*slots = mei_count_full_read_slots(dev);
+	if (*slots == -EOVERFLOW) {
+		/* overflow - reset */
+		dev_err(dev->dev, "resetting due to slots overflow.\n");
+		/* set the event since message has been read */
+		ret = -ERANGE;
+		goto end;
+	}
+end:
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mei_irq_read_handler);
+
+
+/**
+ * mei_irq_write_handler -  dispatch write requests
+ *  after irq received
+ *
+ * @dev: the device structure
+ * @cmpl_list: An instance of our list structure
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int mei_irq_write_handler(struct mei_device *dev, struct list_head *cmpl_list)
+{
+
+	struct mei_cl *cl;
+	struct mei_cl_cb *cb, *next;
+	s32 slots;
+	int ret;
+
+
+	if (!mei_hbuf_acquire(dev))
+		return 0;
+
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if (slots == 0)
+		return -EMSGSIZE;
+
+	/* complete all waiting for write CB */
+	dev_dbg(dev->dev, "complete all waiting for write cb.\n");
+
+	list_for_each_entry_safe(cb, next, &dev->write_waiting_list, list) {
+		cl = cb->cl;
+
+		cl->status = 0;
+		cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
+		cl->writing_state = MEI_WRITE_COMPLETE;
+		list_move_tail(&cb->list, cmpl_list);
+	}
+
+	/* complete control write list CB */
+	dev_dbg(dev->dev, "complete control write list cb.\n");
+	list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list, list) {
+		cl = cb->cl;
+		switch (cb->fop_type) {
+		case MEI_FOP_DISCONNECT:
+			/* send disconnect message */
+			ret = mei_cl_irq_disconnect(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+
+			break;
+		case MEI_FOP_READ:
+			/* send flow control message */
+			ret = mei_cl_irq_read(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+
+			break;
+		case MEI_FOP_CONNECT:
+			/* connect message */
+			ret = mei_cl_irq_connect(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+
+			break;
+		case MEI_FOP_DISCONNECT_RSP:
+			/* send disconnect resp */
+			ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+			break;
+
+		case MEI_FOP_NOTIFY_START:
+		case MEI_FOP_NOTIFY_STOP:
+			ret = mei_cl_irq_notify(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+			break;
+		case MEI_FOP_DMA_MAP:
+			ret = mei_cl_irq_dma_map(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+			break;
+		case MEI_FOP_DMA_UNMAP:
+			ret = mei_cl_irq_dma_unmap(cl, cb, cmpl_list);
+			if (ret)
+				return ret;
+			break;
+		default:
+			BUG();
+		}
+
+	}
+	/* complete  write list CB */
+	dev_dbg(dev->dev, "complete write list cb.\n");
+	list_for_each_entry_safe(cb, next, &dev->write_list, list) {
+		cl = cb->cl;
+		ret = mei_cl_irq_write(cl, cb, cmpl_list);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_irq_write_handler);
+
+
+/**
+ * mei_connect_timeout  - connect/disconnect timeouts
+ *
+ * @cl: host client
+ */
+static void mei_connect_timeout(struct mei_cl *cl)
+{
+	struct mei_device *dev = cl->dev;
+
+	if (cl->state == MEI_FILE_CONNECTING) {
+		if (dev->hbm_f_dot_supported) {
+			cl->state = MEI_FILE_DISCONNECT_REQUIRED;
+			wake_up(&cl->wait);
+			return;
+		}
+	}
+	mei_reset(dev);
+}
+
+#define MEI_STALL_TIMER_FREQ (2 * HZ)
+/**
+ * mei_schedule_stall_timer - re-arm stall_timer work
+ *
+ * Schedule stall timer
+ *
+ * @dev: the device structure
+ */
+void mei_schedule_stall_timer(struct mei_device *dev)
+{
+	schedule_delayed_work(&dev->timer_work, MEI_STALL_TIMER_FREQ);
+}
+
+/**
+ * mei_timer - timer function.
+ *
+ * @work: pointer to the work_struct structure
+ *
+ */
+void mei_timer(struct work_struct *work)
+{
+	struct mei_cl *cl;
+	struct mei_device *dev = container_of(work,
+					struct mei_device, timer_work.work);
+	bool reschedule_timer = false;
+
+	mutex_lock(&dev->device_lock);
+
+	/* Catch interrupt stalls during HBM init handshake */
+	if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
+	    dev->hbm_state != MEI_HBM_IDLE) {
+
+		if (dev->init_clients_timer) {
+			if (--dev->init_clients_timer == 0) {
+				dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n",
+					dev->hbm_state);
+				mei_reset(dev);
+				goto out;
+			}
+			reschedule_timer = true;
+		}
+	}
+
+	if (dev->dev_state != MEI_DEV_ENABLED)
+		goto out;
+
+	/*** connect/disconnect timeouts ***/
+	list_for_each_entry(cl, &dev->file_list, link) {
+		if (cl->timer_count) {
+			if (--cl->timer_count == 0) {
+				dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
+				mei_connect_timeout(cl);
+				goto out;
+			}
+			reschedule_timer = true;
+		}
+	}
+
+out:
+	if (dev->dev_state != MEI_DEV_DISABLED && reschedule_timer)
+		mei_schedule_stall_timer(dev);
+
+	mutex_unlock(&dev->device_lock);
+}