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, 743 insertions, 0 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/ccm_mbox.c b/drivers/net/ethernet/netronome/nfp/ccm_mbox.c
new file mode 100644
index 000000000..aa8aba4ff
--- /dev/null
+++ b/drivers/net/ethernet/netronome/nfp/ccm_mbox.c
@@ -0,0 +1,743 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/* Copyright (C) 2019 Netronome Systems, Inc. */
+
+#include <linux/bitfield.h>
+#include <linux/io.h>
+#include <linux/skbuff.h>
+
+#include "ccm.h"
+#include "nfp_net.h"
+
+/* CCM messages via the mailbox.  CMSGs get wrapped into simple TLVs
+ * and copied into the mailbox.  Multiple messages can be copied to
+ * form a batch.  Threads come in with CMSG formed in an skb, then
+ * enqueue that skb onto the request queue.  If threads skb is first
+ * in queue this thread will handle the mailbox operation.  It copies
+ * up to 64 messages into the mailbox (making sure that both requests
+ * and replies will fit.  After FW is done processing the batch it
+ * copies the data out and wakes waiting threads.
+ * If a thread is waiting it either gets its the message completed
+ * (response is copied into the same skb as the request, overwriting
+ * it), or becomes the first in queue.
+ * Completions and next-to-run are signaled via the control buffer
+ * to limit potential cache line bounces.
+ */
+
+#define NFP_CCM_MBOX_BATCH_LIMIT	64
+#define NFP_CCM_TIMEOUT			(NFP_NET_POLL_TIMEOUT * 1000)
+#define NFP_CCM_MAX_QLEN		1024
+
+enum nfp_net_mbox_cmsg_state {
+	NFP_NET_MBOX_CMSG_STATE_QUEUED,
+	NFP_NET_MBOX_CMSG_STATE_NEXT,
+	NFP_NET_MBOX_CMSG_STATE_BUSY,
+	NFP_NET_MBOX_CMSG_STATE_REPLY_FOUND,
+	NFP_NET_MBOX_CMSG_STATE_DONE,
+};
+
+/**
+ * struct nfp_ccm_mbox_cmsg_cb - CCM mailbox specific info
+ * @state:	processing state (/stage) of the message
+ * @err:	error encountered during processing if any
+ * @max_len:	max(request_len, reply_len)
+ * @exp_reply:	expected reply length (0 means don't validate)
+ * @posted:	the message was posted and nobody waits for the reply
+ */
+struct nfp_ccm_mbox_cmsg_cb {
+	enum nfp_net_mbox_cmsg_state state;
+	int err;
+	unsigned int max_len;
+	unsigned int exp_reply;
+	bool posted;
+};
+
+static u32 nfp_ccm_mbox_max_msg(struct nfp_net *nn)
+{
+	return round_down(nn->tlv_caps.mbox_len, 4) -
+		NFP_NET_CFG_MBOX_SIMPLE_VAL - /* common mbox command header */
+		4 * 2; /* Msg TLV plus End TLV headers */
+}
+
+static void
+nfp_ccm_mbox_msg_init(struct sk_buff *skb, unsigned int exp_reply, int max_len)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb = (void *)skb->cb;
+
+	cb->state = NFP_NET_MBOX_CMSG_STATE_QUEUED;
+	cb->err = 0;
+	cb->max_len = max_len;
+	cb->exp_reply = exp_reply;
+	cb->posted = false;
+}
+
+static int nfp_ccm_mbox_maxlen(const struct sk_buff *skb)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb = (void *)skb->cb;
+
+	return cb->max_len;
+}
+
+static bool nfp_ccm_mbox_done(struct sk_buff *skb)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb = (void *)skb->cb;
+
+	return cb->state == NFP_NET_MBOX_CMSG_STATE_DONE;
+}
+
+static bool nfp_ccm_mbox_in_progress(struct sk_buff *skb)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb = (void *)skb->cb;
+
+	return cb->state != NFP_NET_MBOX_CMSG_STATE_QUEUED &&
+	       cb->state != NFP_NET_MBOX_CMSG_STATE_NEXT;
+}
+
+static void nfp_ccm_mbox_set_busy(struct sk_buff *skb)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb = (void *)skb->cb;
+
+	cb->state = NFP_NET_MBOX_CMSG_STATE_BUSY;
+}
+
+static bool nfp_ccm_mbox_is_posted(struct sk_buff *skb)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb = (void *)skb->cb;
+
+	return cb->posted;
+}
+
+static void nfp_ccm_mbox_mark_posted(struct sk_buff *skb)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb = (void *)skb->cb;
+
+	cb->posted = true;
+}
+
+static bool nfp_ccm_mbox_is_first(struct nfp_net *nn, struct sk_buff *skb)
+{
+	return skb_queue_is_first(&nn->mbox_cmsg.queue, skb);
+}
+
+static bool nfp_ccm_mbox_should_run(struct nfp_net *nn, struct sk_buff *skb)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb = (void *)skb->cb;
+
+	return cb->state == NFP_NET_MBOX_CMSG_STATE_NEXT;
+}
+
+static void nfp_ccm_mbox_mark_next_runner(struct nfp_net *nn)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb;
+	struct sk_buff *skb;
+
+	skb = skb_peek(&nn->mbox_cmsg.queue);
+	if (!skb)
+		return;
+
+	cb = (void *)skb->cb;
+	cb->state = NFP_NET_MBOX_CMSG_STATE_NEXT;
+	if (cb->posted)
+		queue_work(nn->mbox_cmsg.workq, &nn->mbox_cmsg.runq_work);
+}
+
+static void
+nfp_ccm_mbox_write_tlv(struct nfp_net *nn, u32 off, u32 type, u32 len)
+{
+	nn_writel(nn, off,
+		  FIELD_PREP(NFP_NET_MBOX_TLV_TYPE, type) |
+		  FIELD_PREP(NFP_NET_MBOX_TLV_LEN, len));
+}
+
+static void nfp_ccm_mbox_copy_in(struct nfp_net *nn, struct sk_buff *last)
+{
+	struct sk_buff *skb;
+	int reserve, i, cnt;
+	__be32 *data;
+	u32 off, len;
+
+	off = nn->tlv_caps.mbox_off + NFP_NET_CFG_MBOX_SIMPLE_VAL;
+	skb = __skb_peek(&nn->mbox_cmsg.queue);
+	while (true) {
+		nfp_ccm_mbox_write_tlv(nn, off, NFP_NET_MBOX_TLV_TYPE_MSG,
+				       skb->len);
+		off += 4;
+
+		/* Write data word by word, skb->data should be aligned */
+		data = (__be32 *)skb->data;
+		cnt = skb->len / 4;
+		for (i = 0 ; i < cnt; i++) {
+			nn_writel(nn, off, be32_to_cpu(data[i]));
+			off += 4;
+		}
+		if (skb->len & 3) {
+			__be32 tmp = 0;
+
+			memcpy(&tmp, &data[i], skb->len & 3);
+			nn_writel(nn, off, be32_to_cpu(tmp));
+			off += 4;
+		}
+
+		/* Reserve space if reply is bigger */
+		len = round_up(skb->len, 4);
+		reserve = nfp_ccm_mbox_maxlen(skb) - len;
+		if (reserve > 0) {
+			nfp_ccm_mbox_write_tlv(nn, off,
+					       NFP_NET_MBOX_TLV_TYPE_RESV,
+					       reserve);
+			off += 4 + reserve;
+		}
+
+		if (skb == last)
+			break;
+		skb = skb_queue_next(&nn->mbox_cmsg.queue, skb);
+	}
+
+	nfp_ccm_mbox_write_tlv(nn, off, NFP_NET_MBOX_TLV_TYPE_END, 0);
+}
+
+static struct sk_buff *
+nfp_ccm_mbox_find_req(struct nfp_net *nn, __be16 tag, struct sk_buff *last)
+{
+	struct sk_buff *skb;
+
+	skb = __skb_peek(&nn->mbox_cmsg.queue);
+	while (true) {
+		if (__nfp_ccm_get_tag(skb) == tag)
+			return skb;
+
+		if (skb == last)
+			return NULL;
+		skb = skb_queue_next(&nn->mbox_cmsg.queue, skb);
+	}
+}
+
+static void nfp_ccm_mbox_copy_out(struct nfp_net *nn, struct sk_buff *last)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb;
+	u8 __iomem *data, *end;
+	struct sk_buff *skb;
+
+	data = nn->dp.ctrl_bar + nn->tlv_caps.mbox_off +
+		NFP_NET_CFG_MBOX_SIMPLE_VAL;
+	end = data + nn->tlv_caps.mbox_len;
+
+	while (true) {
+		unsigned int length, offset, type;
+		struct nfp_ccm_hdr hdr;
+		u32 tlv_hdr;
+
+		tlv_hdr = readl(data);
+		type = FIELD_GET(NFP_NET_MBOX_TLV_TYPE, tlv_hdr);
+		length = FIELD_GET(NFP_NET_MBOX_TLV_LEN, tlv_hdr);
+		offset = data - nn->dp.ctrl_bar;
+
+		/* Advance past the header */
+		data += 4;
+
+		if (data + length > end) {
+			nn_dp_warn(&nn->dp, "mailbox oversized TLV type:%d offset:%u len:%u\n",
+				   type, offset, length);
+			break;
+		}
+
+		if (type == NFP_NET_MBOX_TLV_TYPE_END)
+			break;
+		if (type == NFP_NET_MBOX_TLV_TYPE_RESV)
+			goto next_tlv;
+		if (type != NFP_NET_MBOX_TLV_TYPE_MSG &&
+		    type != NFP_NET_MBOX_TLV_TYPE_MSG_NOSUP) {
+			nn_dp_warn(&nn->dp, "mailbox unknown TLV type:%d offset:%u len:%u\n",
+				   type, offset, length);
+			break;
+		}
+
+		if (length < 4) {
+			nn_dp_warn(&nn->dp, "mailbox msg too short to contain header TLV type:%d offset:%u len:%u\n",
+				   type, offset, length);
+			break;
+		}
+
+		hdr.raw = cpu_to_be32(readl(data));
+
+		skb = nfp_ccm_mbox_find_req(nn, hdr.tag, last);
+		if (!skb) {
+			nn_dp_warn(&nn->dp, "mailbox request not found:%u\n",
+				   be16_to_cpu(hdr.tag));
+			break;
+		}
+		cb = (void *)skb->cb;
+
+		if (type == NFP_NET_MBOX_TLV_TYPE_MSG_NOSUP) {
+			nn_dp_warn(&nn->dp,
+				   "mailbox msg not supported type:%d\n",
+				   nfp_ccm_get_type(skb));
+			cb->err = -EIO;
+			goto next_tlv;
+		}
+
+		if (hdr.type != __NFP_CCM_REPLY(nfp_ccm_get_type(skb))) {
+			nn_dp_warn(&nn->dp, "mailbox msg reply wrong type:%u expected:%lu\n",
+				   hdr.type,
+				   __NFP_CCM_REPLY(nfp_ccm_get_type(skb)));
+			cb->err = -EIO;
+			goto next_tlv;
+		}
+		if (cb->exp_reply && length != cb->exp_reply) {
+			nn_dp_warn(&nn->dp, "mailbox msg reply wrong size type:%u expected:%u have:%u\n",
+				   hdr.type, length, cb->exp_reply);
+			cb->err = -EIO;
+			goto next_tlv;
+		}
+		if (length > cb->max_len) {
+			nn_dp_warn(&nn->dp, "mailbox msg oversized reply type:%u max:%u have:%u\n",
+				   hdr.type, cb->max_len, length);
+			cb->err = -EIO;
+			goto next_tlv;
+		}
+
+		if (!cb->posted) {
+			__be32 *skb_data;
+			int i, cnt;
+
+			if (length <= skb->len)
+				__skb_trim(skb, length);
+			else
+				skb_put(skb, length - skb->len);
+
+			/* We overcopy here slightly, but that's okay,
+			 * the skb is large enough, and the garbage will
+			 * be ignored (beyond skb->len).
+			 */
+			skb_data = (__be32 *)skb->data;
+			memcpy(skb_data, &hdr, 4);
+
+			cnt = DIV_ROUND_UP(length, 4);
+			for (i = 1 ; i < cnt; i++)
+				skb_data[i] = cpu_to_be32(readl(data + i * 4));
+		}
+
+		cb->state = NFP_NET_MBOX_CMSG_STATE_REPLY_FOUND;
+next_tlv:
+		data += round_up(length, 4);
+		if (data + 4 > end) {
+			nn_dp_warn(&nn->dp,
+				   "reached end of MBOX without END TLV\n");
+			break;
+		}
+	}
+
+	smp_wmb(); /* order the skb->data vs. cb->state */
+	spin_lock_bh(&nn->mbox_cmsg.queue.lock);
+	do {
+		skb = __skb_dequeue(&nn->mbox_cmsg.queue);
+		cb = (void *)skb->cb;
+
+		if (cb->state != NFP_NET_MBOX_CMSG_STATE_REPLY_FOUND) {
+			cb->err = -ENOENT;
+			smp_wmb(); /* order the cb->err vs. cb->state */
+		}
+		cb->state = NFP_NET_MBOX_CMSG_STATE_DONE;
+
+		if (cb->posted) {
+			if (cb->err)
+				nn_dp_warn(&nn->dp,
+					   "mailbox posted msg failed type:%u err:%d\n",
+					   nfp_ccm_get_type(skb), cb->err);
+			dev_consume_skb_any(skb);
+		}
+	} while (skb != last);
+
+	nfp_ccm_mbox_mark_next_runner(nn);
+	spin_unlock_bh(&nn->mbox_cmsg.queue.lock);
+}
+
+static void
+nfp_ccm_mbox_mark_all_err(struct nfp_net *nn, struct sk_buff *last, int err)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb;
+	struct sk_buff *skb;
+
+	spin_lock_bh(&nn->mbox_cmsg.queue.lock);
+	do {
+		skb = __skb_dequeue(&nn->mbox_cmsg.queue);
+		cb = (void *)skb->cb;
+
+		cb->err = err;
+		smp_wmb(); /* order the cb->err vs. cb->state */
+		cb->state = NFP_NET_MBOX_CMSG_STATE_DONE;
+	} while (skb != last);
+
+	nfp_ccm_mbox_mark_next_runner(nn);
+	spin_unlock_bh(&nn->mbox_cmsg.queue.lock);
+}
+
+static void nfp_ccm_mbox_run_queue_unlock(struct nfp_net *nn)
+	__releases(&nn->mbox_cmsg.queue.lock)
+{
+	int space = nn->tlv_caps.mbox_len - NFP_NET_CFG_MBOX_SIMPLE_VAL;
+	struct sk_buff *skb, *last;
+	int cnt, err;
+
+	space -= 4; /* for End TLV */
+
+	/* First skb must fit, because it's ours and we checked it fits */
+	cnt = 1;
+	last = skb = __skb_peek(&nn->mbox_cmsg.queue);
+	space -= 4 + nfp_ccm_mbox_maxlen(skb);
+
+	while (!skb_queue_is_last(&nn->mbox_cmsg.queue, last)) {
+		skb = skb_queue_next(&nn->mbox_cmsg.queue, last);
+		space -= 4 + nfp_ccm_mbox_maxlen(skb);
+		if (space < 0)
+			break;
+		last = skb;
+		nfp_ccm_mbox_set_busy(skb);
+		cnt++;
+		if (cnt == NFP_CCM_MBOX_BATCH_LIMIT)
+			break;
+	}
+	spin_unlock_bh(&nn->mbox_cmsg.queue.lock);
+
+	/* Now we own all skb's marked in progress, new requests may arrive
+	 * at the end of the queue.
+	 */
+
+	nn_ctrl_bar_lock(nn);
+
+	nfp_ccm_mbox_copy_in(nn, last);
+
+	err = nfp_net_mbox_reconfig(nn, NFP_NET_CFG_MBOX_CMD_TLV_CMSG);
+	if (!err)
+		nfp_ccm_mbox_copy_out(nn, last);
+	else
+		nfp_ccm_mbox_mark_all_err(nn, last, -EIO);
+
+	nn_ctrl_bar_unlock(nn);
+
+	wake_up_all(&nn->mbox_cmsg.wq);
+}
+
+static int nfp_ccm_mbox_skb_return(struct sk_buff *skb)
+{
+	struct nfp_ccm_mbox_cmsg_cb *cb = (void *)skb->cb;
+
+	if (cb->err)
+		dev_kfree_skb_any(skb);
+	return cb->err;
+}
+
+/* If wait timed out but the command is already in progress we have
+ * to wait until it finishes.  Runners has ownership of the skbs marked
+ * as busy.
+ */
+static int
+nfp_ccm_mbox_unlink_unlock(struct nfp_net *nn, struct sk_buff *skb,
+			   enum nfp_ccm_type type)
+	__releases(&nn->mbox_cmsg.queue.lock)
+{
+	bool was_first;
+
+	if (nfp_ccm_mbox_in_progress(skb)) {
+		spin_unlock_bh(&nn->mbox_cmsg.queue.lock);
+
+		wait_event(nn->mbox_cmsg.wq, nfp_ccm_mbox_done(skb));
+		smp_rmb(); /* pairs with smp_wmb() after data is written */
+		return nfp_ccm_mbox_skb_return(skb);
+	}
+
+	was_first = nfp_ccm_mbox_should_run(nn, skb);
+	__skb_unlink(skb, &nn->mbox_cmsg.queue);
+	if (was_first)
+		nfp_ccm_mbox_mark_next_runner(nn);
+
+	spin_unlock_bh(&nn->mbox_cmsg.queue.lock);
+
+	if (was_first)
+		wake_up_all(&nn->mbox_cmsg.wq);
+
+	nn_dp_warn(&nn->dp, "time out waiting for mbox response to 0x%02x\n",
+		   type);
+	return -ETIMEDOUT;
+}
+
+static int
+nfp_ccm_mbox_msg_prepare(struct nfp_net *nn, struct sk_buff *skb,
+			 enum nfp_ccm_type type,
+			 unsigned int reply_size, unsigned int max_reply_size,
+			 gfp_t flags)
+{
+	const unsigned int mbox_max = nfp_ccm_mbox_max_msg(nn);
+	unsigned int max_len;
+	ssize_t undersize;
+	int err;
+
+	if (unlikely(!(nn->tlv_caps.mbox_cmsg_types & BIT(type)))) {
+		nn_dp_warn(&nn->dp,
+			   "message type %d not supported by mailbox\n", type);
+		return -EINVAL;
+	}
+
+	/* If the reply size is unknown assume it will take the entire
+	 * mailbox, the callers should do their best for this to never
+	 * happen.
+	 */
+	if (!max_reply_size)
+		max_reply_size = mbox_max;
+	max_reply_size = round_up(max_reply_size, 4);
+
+	/* Make sure we can fit the entire reply into the skb,
+	 * and that we don't have to slow down the mbox handler
+	 * with allocations.
+	 */
+	undersize = max_reply_size - (skb_end_pointer(skb) - skb->data);
+	if (undersize > 0) {
+		err = pskb_expand_head(skb, 0, undersize, flags);
+		if (err) {
+			nn_dp_warn(&nn->dp,
+				   "can't allocate reply buffer for mailbox\n");
+			return err;
+		}
+	}
+
+	/* Make sure that request and response both fit into the mailbox */
+	max_len = max(max_reply_size, round_up(skb->len, 4));
+	if (max_len > mbox_max) {
+		nn_dp_warn(&nn->dp,
+			   "message too big for the mailbox: %u/%u vs %u\n",
+			   skb->len, max_reply_size, mbox_max);
+		return -EMSGSIZE;
+	}
+
+	nfp_ccm_mbox_msg_init(skb, reply_size, max_len);
+
+	return 0;
+}
+
+static int
+nfp_ccm_mbox_msg_enqueue(struct nfp_net *nn, struct sk_buff *skb,
+			 enum nfp_ccm_type type, bool critical)
+{
+	struct nfp_ccm_hdr *hdr;
+
+	assert_spin_locked(&nn->mbox_cmsg.queue.lock);
+
+	if (!critical && nn->mbox_cmsg.queue.qlen >= NFP_CCM_MAX_QLEN) {
+		nn_dp_warn(&nn->dp, "mailbox request queue too long\n");
+		return -EBUSY;
+	}
+
+	hdr = (void *)skb->data;
+	hdr->ver = NFP_CCM_ABI_VERSION;
+	hdr->type = type;
+	hdr->tag = cpu_to_be16(nn->mbox_cmsg.tag++);
+
+	__skb_queue_tail(&nn->mbox_cmsg.queue, skb);
+
+	return 0;
+}
+
+int __nfp_ccm_mbox_communicate(struct nfp_net *nn, struct sk_buff *skb,
+			       enum nfp_ccm_type type,
+			       unsigned int reply_size,
+			       unsigned int max_reply_size, bool critical)
+{
+	int err;
+
+	err = nfp_ccm_mbox_msg_prepare(nn, skb, type, reply_size,
+				       max_reply_size, GFP_KERNEL);
+	if (err)
+		goto err_free_skb;
+
+	spin_lock_bh(&nn->mbox_cmsg.queue.lock);
+
+	err = nfp_ccm_mbox_msg_enqueue(nn, skb, type, critical);
+	if (err)
+		goto err_unlock;
+
+	/* First in queue takes the mailbox lock and processes the batch */
+	if (!nfp_ccm_mbox_is_first(nn, skb)) {
+		bool to;
+
+		spin_unlock_bh(&nn->mbox_cmsg.queue.lock);
+
+		to = !wait_event_timeout(nn->mbox_cmsg.wq,
+					 nfp_ccm_mbox_done(skb) ||
+					 nfp_ccm_mbox_should_run(nn, skb),
+					 msecs_to_jiffies(NFP_CCM_TIMEOUT));
+
+		/* fast path for those completed by another thread */
+		if (nfp_ccm_mbox_done(skb)) {
+			smp_rmb(); /* pairs with wmb after data is written */
+			return nfp_ccm_mbox_skb_return(skb);
+		}
+
+		spin_lock_bh(&nn->mbox_cmsg.queue.lock);
+
+		if (!nfp_ccm_mbox_is_first(nn, skb)) {
+			WARN_ON(!to);
+
+			err = nfp_ccm_mbox_unlink_unlock(nn, skb, type);
+			if (err)
+				goto err_free_skb;
+			return 0;
+		}
+	}
+
+	/* run queue expects the lock held */
+	nfp_ccm_mbox_run_queue_unlock(nn);
+	return nfp_ccm_mbox_skb_return(skb);
+
+err_unlock:
+	spin_unlock_bh(&nn->mbox_cmsg.queue.lock);
+err_free_skb:
+	dev_kfree_skb_any(skb);
+	return err;
+}
+
+int nfp_ccm_mbox_communicate(struct nfp_net *nn, struct sk_buff *skb,
+			     enum nfp_ccm_type type,
+			     unsigned int reply_size,
+			     unsigned int max_reply_size)
+{
+	return __nfp_ccm_mbox_communicate(nn, skb, type, reply_size,
+					  max_reply_size, false);
+}
+
+static void nfp_ccm_mbox_post_runq_work(struct work_struct *work)
+{
+	struct sk_buff *skb;
+	struct nfp_net *nn;
+
+	nn = container_of(work, struct nfp_net, mbox_cmsg.runq_work);
+
+	spin_lock_bh(&nn->mbox_cmsg.queue.lock);
+
+	skb = __skb_peek(&nn->mbox_cmsg.queue);
+	if (WARN_ON(!skb || !nfp_ccm_mbox_is_posted(skb) ||
+		    !nfp_ccm_mbox_should_run(nn, skb))) {
+		spin_unlock_bh(&nn->mbox_cmsg.queue.lock);
+		return;
+	}
+
+	nfp_ccm_mbox_run_queue_unlock(nn);
+}
+
+static void nfp_ccm_mbox_post_wait_work(struct work_struct *work)
+{
+	struct sk_buff *skb;
+	struct nfp_net *nn;
+	int err;
+
+	nn = container_of(work, struct nfp_net, mbox_cmsg.wait_work);
+
+	skb = skb_peek(&nn->mbox_cmsg.queue);
+	if (WARN_ON(!skb || !nfp_ccm_mbox_is_posted(skb)))
+		/* Should never happen so it's unclear what to do here.. */
+		goto exit_unlock_wake;
+
+	err = nfp_net_mbox_reconfig_wait_posted(nn);
+	if (!err)
+		nfp_ccm_mbox_copy_out(nn, skb);
+	else
+		nfp_ccm_mbox_mark_all_err(nn, skb, -EIO);
+exit_unlock_wake:
+	nn_ctrl_bar_unlock(nn);
+	wake_up_all(&nn->mbox_cmsg.wq);
+}
+
+int nfp_ccm_mbox_post(struct nfp_net *nn, struct sk_buff *skb,
+		      enum nfp_ccm_type type, unsigned int max_reply_size)
+{
+	int err;
+
+	err = nfp_ccm_mbox_msg_prepare(nn, skb, type, 0, max_reply_size,
+				       GFP_ATOMIC);
+	if (err)
+		goto err_free_skb;
+
+	nfp_ccm_mbox_mark_posted(skb);
+
+	spin_lock_bh(&nn->mbox_cmsg.queue.lock);
+
+	err = nfp_ccm_mbox_msg_enqueue(nn, skb, type, false);
+	if (err)
+		goto err_unlock;
+
+	if (nfp_ccm_mbox_is_first(nn, skb)) {
+		if (nn_ctrl_bar_trylock(nn)) {
+			nfp_ccm_mbox_copy_in(nn, skb);
+			nfp_net_mbox_reconfig_post(nn,
+						   NFP_NET_CFG_MBOX_CMD_TLV_CMSG);
+			queue_work(nn->mbox_cmsg.workq,
+				   &nn->mbox_cmsg.wait_work);
+		} else {
+			nfp_ccm_mbox_mark_next_runner(nn);
+		}
+	}
+
+	spin_unlock_bh(&nn->mbox_cmsg.queue.lock);
+
+	return 0;
+
+err_unlock:
+	spin_unlock_bh(&nn->mbox_cmsg.queue.lock);
+err_free_skb:
+	dev_kfree_skb_any(skb);
+	return err;
+}
+
+struct sk_buff *
+nfp_ccm_mbox_msg_alloc(struct nfp_net *nn, unsigned int req_size,
+		       unsigned int reply_size, gfp_t flags)
+{
+	unsigned int max_size;
+	struct sk_buff *skb;
+
+	if (!reply_size)
+		max_size = nfp_ccm_mbox_max_msg(nn);
+	else
+		max_size = max(req_size, reply_size);
+	max_size = round_up(max_size, 4);
+
+	skb = alloc_skb(max_size, flags);
+	if (!skb)
+		return NULL;
+
+	skb_put(skb, req_size);
+
+	return skb;
+}
+
+bool nfp_ccm_mbox_fits(struct nfp_net *nn, unsigned int size)
+{
+	return nfp_ccm_mbox_max_msg(nn) >= size;
+}
+
+int nfp_ccm_mbox_init(struct nfp_net *nn)
+{
+	return 0;
+}
+
+void nfp_ccm_mbox_clean(struct nfp_net *nn)
+{
+	drain_workqueue(nn->mbox_cmsg.workq);
+}
+
+int nfp_ccm_mbox_alloc(struct nfp_net *nn)
+{
+	skb_queue_head_init(&nn->mbox_cmsg.queue);
+	init_waitqueue_head(&nn->mbox_cmsg.wq);
+	INIT_WORK(&nn->mbox_cmsg.wait_work, nfp_ccm_mbox_post_wait_work);
+	INIT_WORK(&nn->mbox_cmsg.runq_work, nfp_ccm_mbox_post_runq_work);
+
+	nn->mbox_cmsg.workq = alloc_workqueue("nfp-ccm-mbox", WQ_UNBOUND, 0);
+	if (!nn->mbox_cmsg.workq)
+		return -ENOMEM;
+	return 0;
+}
+
+void nfp_ccm_mbox_free(struct nfp_net *nn)
+{
+	destroy_workqueue(nn->mbox_cmsg.workq);
+	WARN_ON(!skb_queue_empty(&nn->mbox_cmsg.queue));
+}