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, 863 insertions, 0 deletions

diff --git a/drivers/net/ethernet/google/gve/gve_rx.c b/drivers/net/ethernet/google/gve/gve_rx.c
new file mode 100644
index 000000000..1f5513772
--- /dev/null
+++ b/drivers/net/ethernet/google/gve/gve_rx.c
@@ -0,0 +1,863 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/* Google virtual Ethernet (gve) driver
+ *
+ * Copyright (C) 2015-2021 Google, Inc.
+ */
+
+#include "gve.h"
+#include "gve_adminq.h"
+#include "gve_utils.h"
+#include <linux/etherdevice.h>
+
+static void gve_rx_free_buffer(struct device *dev,
+			       struct gve_rx_slot_page_info *page_info,
+			       union gve_rx_data_slot *data_slot)
+{
+	dma_addr_t dma = (dma_addr_t)(be64_to_cpu(data_slot->addr) &
+				      GVE_DATA_SLOT_ADDR_PAGE_MASK);
+
+	page_ref_sub(page_info->page, page_info->pagecnt_bias - 1);
+	gve_free_page(dev, page_info->page, dma, DMA_FROM_DEVICE);
+}
+
+static void gve_rx_unfill_pages(struct gve_priv *priv, struct gve_rx_ring *rx)
+{
+	u32 slots = rx->mask + 1;
+	int i;
+
+	if (rx->data.raw_addressing) {
+		for (i = 0; i < slots; i++)
+			gve_rx_free_buffer(&priv->pdev->dev, &rx->data.page_info[i],
+					   &rx->data.data_ring[i]);
+	} else {
+		for (i = 0; i < slots; i++)
+			page_ref_sub(rx->data.page_info[i].page,
+				     rx->data.page_info[i].pagecnt_bias - 1);
+		gve_unassign_qpl(priv, rx->data.qpl->id);
+		rx->data.qpl = NULL;
+
+		for (i = 0; i < rx->qpl_copy_pool_mask + 1; i++) {
+			page_ref_sub(rx->qpl_copy_pool[i].page,
+				     rx->qpl_copy_pool[i].pagecnt_bias - 1);
+			put_page(rx->qpl_copy_pool[i].page);
+		}
+	}
+	kvfree(rx->data.page_info);
+	rx->data.page_info = NULL;
+}
+
+static void gve_rx_free_ring(struct gve_priv *priv, int idx)
+{
+	struct gve_rx_ring *rx = &priv->rx[idx];
+	struct device *dev = &priv->pdev->dev;
+	u32 slots = rx->mask + 1;
+	size_t bytes;
+
+	gve_rx_remove_from_block(priv, idx);
+
+	bytes = sizeof(struct gve_rx_desc) * priv->rx_desc_cnt;
+	dma_free_coherent(dev, bytes, rx->desc.desc_ring, rx->desc.bus);
+	rx->desc.desc_ring = NULL;
+
+	dma_free_coherent(dev, sizeof(*rx->q_resources),
+			  rx->q_resources, rx->q_resources_bus);
+	rx->q_resources = NULL;
+
+	gve_rx_unfill_pages(priv, rx);
+
+	bytes = sizeof(*rx->data.data_ring) * slots;
+	dma_free_coherent(dev, bytes, rx->data.data_ring,
+			  rx->data.data_bus);
+	rx->data.data_ring = NULL;
+
+	kvfree(rx->qpl_copy_pool);
+	rx->qpl_copy_pool = NULL;
+
+	netif_dbg(priv, drv, priv->dev, "freed rx ring %d\n", idx);
+}
+
+static void gve_setup_rx_buffer(struct gve_rx_slot_page_info *page_info,
+			     dma_addr_t addr, struct page *page, __be64 *slot_addr)
+{
+	page_info->page = page;
+	page_info->page_offset = 0;
+	page_info->page_address = page_address(page);
+	*slot_addr = cpu_to_be64(addr);
+	/* The page already has 1 ref */
+	page_ref_add(page, INT_MAX - 1);
+	page_info->pagecnt_bias = INT_MAX;
+}
+
+static int gve_rx_alloc_buffer(struct gve_priv *priv, struct device *dev,
+			       struct gve_rx_slot_page_info *page_info,
+			       union gve_rx_data_slot *data_slot)
+{
+	struct page *page;
+	dma_addr_t dma;
+	int err;
+
+	err = gve_alloc_page(priv, dev, &page, &dma, DMA_FROM_DEVICE,
+			     GFP_ATOMIC);
+	if (err)
+		return err;
+
+	gve_setup_rx_buffer(page_info, dma, page, &data_slot->addr);
+	return 0;
+}
+
+static int gve_prefill_rx_pages(struct gve_rx_ring *rx)
+{
+	struct gve_priv *priv = rx->gve;
+	u32 slots;
+	int err;
+	int i;
+	int j;
+
+	/* Allocate one page per Rx queue slot. Each page is split into two
+	 * packet buffers, when possible we "page flip" between the two.
+	 */
+	slots = rx->mask + 1;
+
+	rx->data.page_info = kvzalloc(slots *
+				      sizeof(*rx->data.page_info), GFP_KERNEL);
+	if (!rx->data.page_info)
+		return -ENOMEM;
+
+	if (!rx->data.raw_addressing) {
+		rx->data.qpl = gve_assign_rx_qpl(priv);
+		if (!rx->data.qpl) {
+			kvfree(rx->data.page_info);
+			rx->data.page_info = NULL;
+			return -ENOMEM;
+		}
+	}
+	for (i = 0; i < slots; i++) {
+		if (!rx->data.raw_addressing) {
+			struct page *page = rx->data.qpl->pages[i];
+			dma_addr_t addr = i * PAGE_SIZE;
+
+			gve_setup_rx_buffer(&rx->data.page_info[i], addr, page,
+					    &rx->data.data_ring[i].qpl_offset);
+			continue;
+		}
+		err = gve_rx_alloc_buffer(priv, &priv->pdev->dev, &rx->data.page_info[i],
+					  &rx->data.data_ring[i]);
+		if (err)
+			goto alloc_err;
+	}
+
+	if (!rx->data.raw_addressing) {
+		for (j = 0; j < rx->qpl_copy_pool_mask + 1; j++) {
+			struct page *page = alloc_page(GFP_KERNEL);
+
+			if (!page) {
+				err = -ENOMEM;
+				goto alloc_err_qpl;
+			}
+
+			rx->qpl_copy_pool[j].page = page;
+			rx->qpl_copy_pool[j].page_offset = 0;
+			rx->qpl_copy_pool[j].page_address = page_address(page);
+
+			/* The page already has 1 ref. */
+			page_ref_add(page, INT_MAX - 1);
+			rx->qpl_copy_pool[j].pagecnt_bias = INT_MAX;
+		}
+	}
+
+	return slots;
+
+alloc_err_qpl:
+	while (j--) {
+		page_ref_sub(rx->qpl_copy_pool[j].page,
+			     rx->qpl_copy_pool[j].pagecnt_bias - 1);
+		put_page(rx->qpl_copy_pool[j].page);
+	}
+alloc_err:
+	while (i--)
+		gve_rx_free_buffer(&priv->pdev->dev,
+				   &rx->data.page_info[i],
+				   &rx->data.data_ring[i]);
+	return err;
+}
+
+static void gve_rx_ctx_clear(struct gve_rx_ctx *ctx)
+{
+	ctx->skb_head = NULL;
+	ctx->skb_tail = NULL;
+	ctx->total_size = 0;
+	ctx->frag_cnt = 0;
+	ctx->drop_pkt = false;
+}
+
+static int gve_rx_alloc_ring(struct gve_priv *priv, int idx)
+{
+	struct gve_rx_ring *rx = &priv->rx[idx];
+	struct device *hdev = &priv->pdev->dev;
+	u32 slots, npages;
+	int filled_pages;
+	size_t bytes;
+	int err;
+
+	netif_dbg(priv, drv, priv->dev, "allocating rx ring\n");
+	/* Make sure everything is zeroed to start with */
+	memset(rx, 0, sizeof(*rx));
+
+	rx->gve = priv;
+	rx->q_num = idx;
+
+	slots = priv->rx_data_slot_cnt;
+	rx->mask = slots - 1;
+	rx->data.raw_addressing = priv->queue_format == GVE_GQI_RDA_FORMAT;
+
+	/* alloc rx data ring */
+	bytes = sizeof(*rx->data.data_ring) * slots;
+	rx->data.data_ring = dma_alloc_coherent(hdev, bytes,
+						&rx->data.data_bus,
+						GFP_KERNEL);
+	if (!rx->data.data_ring)
+		return -ENOMEM;
+
+	rx->qpl_copy_pool_mask = min_t(u32, U32_MAX, slots * 2) - 1;
+	rx->qpl_copy_pool_head = 0;
+	rx->qpl_copy_pool = kvcalloc(rx->qpl_copy_pool_mask + 1,
+				     sizeof(rx->qpl_copy_pool[0]),
+				     GFP_KERNEL);
+
+	if (!rx->qpl_copy_pool) {
+		err = -ENOMEM;
+		goto abort_with_slots;
+	}
+
+	filled_pages = gve_prefill_rx_pages(rx);
+	if (filled_pages < 0) {
+		err = -ENOMEM;
+		goto abort_with_copy_pool;
+	}
+	rx->fill_cnt = filled_pages;
+	/* Ensure data ring slots (packet buffers) are visible. */
+	dma_wmb();
+
+	/* Alloc gve_queue_resources */
+	rx->q_resources =
+		dma_alloc_coherent(hdev,
+				   sizeof(*rx->q_resources),
+				   &rx->q_resources_bus,
+				   GFP_KERNEL);
+	if (!rx->q_resources) {
+		err = -ENOMEM;
+		goto abort_filled;
+	}
+	netif_dbg(priv, drv, priv->dev, "rx[%d]->data.data_bus=%lx\n", idx,
+		  (unsigned long)rx->data.data_bus);
+
+	/* alloc rx desc ring */
+	bytes = sizeof(struct gve_rx_desc) * priv->rx_desc_cnt;
+	npages = bytes / PAGE_SIZE;
+	if (npages * PAGE_SIZE != bytes) {
+		err = -EIO;
+		goto abort_with_q_resources;
+	}
+
+	rx->desc.desc_ring = dma_alloc_coherent(hdev, bytes, &rx->desc.bus,
+						GFP_KERNEL);
+	if (!rx->desc.desc_ring) {
+		err = -ENOMEM;
+		goto abort_with_q_resources;
+	}
+	rx->cnt = 0;
+	rx->db_threshold = priv->rx_desc_cnt / 2;
+	rx->desc.seqno = 1;
+
+	/* Allocating half-page buffers allows page-flipping which is faster
+	 * than copying or allocating new pages.
+	 */
+	rx->packet_buffer_size = PAGE_SIZE / 2;
+	gve_rx_ctx_clear(&rx->ctx);
+	gve_rx_add_to_block(priv, idx);
+
+	return 0;
+
+abort_with_q_resources:
+	dma_free_coherent(hdev, sizeof(*rx->q_resources),
+			  rx->q_resources, rx->q_resources_bus);
+	rx->q_resources = NULL;
+abort_filled:
+	gve_rx_unfill_pages(priv, rx);
+abort_with_copy_pool:
+	kvfree(rx->qpl_copy_pool);
+	rx->qpl_copy_pool = NULL;
+abort_with_slots:
+	bytes = sizeof(*rx->data.data_ring) * slots;
+	dma_free_coherent(hdev, bytes, rx->data.data_ring, rx->data.data_bus);
+	rx->data.data_ring = NULL;
+
+	return err;
+}
+
+int gve_rx_alloc_rings(struct gve_priv *priv)
+{
+	int err = 0;
+	int i;
+
+	for (i = 0; i < priv->rx_cfg.num_queues; i++) {
+		err = gve_rx_alloc_ring(priv, i);
+		if (err) {
+			netif_err(priv, drv, priv->dev,
+				  "Failed to alloc rx ring=%d: err=%d\n",
+				  i, err);
+			break;
+		}
+	}
+	/* Unallocate if there was an error */
+	if (err) {
+		int j;
+
+		for (j = 0; j < i; j++)
+			gve_rx_free_ring(priv, j);
+	}
+	return err;
+}
+
+void gve_rx_free_rings_gqi(struct gve_priv *priv)
+{
+	int i;
+
+	for (i = 0; i < priv->rx_cfg.num_queues; i++)
+		gve_rx_free_ring(priv, i);
+}
+
+void gve_rx_write_doorbell(struct gve_priv *priv, struct gve_rx_ring *rx)
+{
+	u32 db_idx = be32_to_cpu(rx->q_resources->db_index);
+
+	iowrite32be(rx->fill_cnt, &priv->db_bar2[db_idx]);
+}
+
+static enum pkt_hash_types gve_rss_type(__be16 pkt_flags)
+{
+	if (likely(pkt_flags & (GVE_RXF_TCP | GVE_RXF_UDP)))
+		return PKT_HASH_TYPE_L4;
+	if (pkt_flags & (GVE_RXF_IPV4 | GVE_RXF_IPV6))
+		return PKT_HASH_TYPE_L3;
+	return PKT_HASH_TYPE_L2;
+}
+
+static struct sk_buff *gve_rx_add_frags(struct napi_struct *napi,
+					struct gve_rx_slot_page_info *page_info,
+					u16 packet_buffer_size, u16 len,
+					struct gve_rx_ctx *ctx)
+{
+	u32 offset = page_info->page_offset + page_info->pad;
+	struct sk_buff *skb = ctx->skb_tail;
+	int num_frags = 0;
+
+	if (!skb) {
+		skb = napi_get_frags(napi);
+		if (unlikely(!skb))
+			return NULL;
+
+		ctx->skb_head = skb;
+		ctx->skb_tail = skb;
+	} else {
+		num_frags = skb_shinfo(ctx->skb_tail)->nr_frags;
+		if (num_frags == MAX_SKB_FRAGS) {
+			skb = napi_alloc_skb(napi, 0);
+			if (!skb)
+				return NULL;
+
+			// We will never chain more than two SKBs: 2 * 16 * 2k > 64k
+			// which is why we do not need to chain by using skb->next
+			skb_shinfo(ctx->skb_tail)->frag_list = skb;
+
+			ctx->skb_tail = skb;
+			num_frags = 0;
+		}
+	}
+
+	if (skb != ctx->skb_head) {
+		ctx->skb_head->len += len;
+		ctx->skb_head->data_len += len;
+		ctx->skb_head->truesize += packet_buffer_size;
+	}
+	skb_add_rx_frag(skb, num_frags, page_info->page,
+			offset, len, packet_buffer_size);
+
+	return ctx->skb_head;
+}
+
+static void gve_rx_flip_buff(struct gve_rx_slot_page_info *page_info, __be64 *slot_addr)
+{
+	const __be64 offset = cpu_to_be64(PAGE_SIZE / 2);
+
+	/* "flip" to other packet buffer on this page */
+	page_info->page_offset ^= PAGE_SIZE / 2;
+	*(slot_addr) ^= offset;
+}
+
+static int gve_rx_can_recycle_buffer(struct gve_rx_slot_page_info *page_info)
+{
+	int pagecount = page_count(page_info->page);
+
+	/* This page is not being used by any SKBs - reuse */
+	if (pagecount == page_info->pagecnt_bias)
+		return 1;
+	/* This page is still being used by an SKB - we can't reuse */
+	else if (pagecount > page_info->pagecnt_bias)
+		return 0;
+	WARN(pagecount < page_info->pagecnt_bias,
+	     "Pagecount should never be less than the bias.");
+	return -1;
+}
+
+static struct sk_buff *
+gve_rx_raw_addressing(struct device *dev, struct net_device *netdev,
+		      struct gve_rx_slot_page_info *page_info, u16 len,
+		      struct napi_struct *napi,
+		      union gve_rx_data_slot *data_slot,
+		      u16 packet_buffer_size, struct gve_rx_ctx *ctx)
+{
+	struct sk_buff *skb = gve_rx_add_frags(napi, page_info, packet_buffer_size, len, ctx);
+
+	if (!skb)
+		return NULL;
+
+	/* Optimistically stop the kernel from freeing the page.
+	 * We will check again in refill to determine if we need to alloc a
+	 * new page.
+	 */
+	gve_dec_pagecnt_bias(page_info);
+
+	return skb;
+}
+
+static struct sk_buff *gve_rx_copy_to_pool(struct gve_rx_ring *rx,
+					   struct gve_rx_slot_page_info *page_info,
+					   u16 len, struct napi_struct *napi)
+{
+	u32 pool_idx = rx->qpl_copy_pool_head & rx->qpl_copy_pool_mask;
+	void *src = page_info->page_address + page_info->page_offset;
+	struct gve_rx_slot_page_info *copy_page_info;
+	struct gve_rx_ctx *ctx = &rx->ctx;
+	bool alloc_page = false;
+	struct sk_buff *skb;
+	void *dst;
+
+	copy_page_info = &rx->qpl_copy_pool[pool_idx];
+	if (!copy_page_info->can_flip) {
+		int recycle = gve_rx_can_recycle_buffer(copy_page_info);
+
+		if (unlikely(recycle < 0)) {
+			gve_schedule_reset(rx->gve);
+			return NULL;
+		}
+		alloc_page = !recycle;
+	}
+
+	if (alloc_page) {
+		struct gve_rx_slot_page_info alloc_page_info;
+		struct page *page;
+
+		/* The least recently used page turned out to be
+		 * still in use by the kernel. Ignoring it and moving
+		 * on alleviates head-of-line blocking.
+		 */
+		rx->qpl_copy_pool_head++;
+
+		page = alloc_page(GFP_ATOMIC);
+		if (!page)
+			return NULL;
+
+		alloc_page_info.page = page;
+		alloc_page_info.page_offset = 0;
+		alloc_page_info.page_address = page_address(page);
+		alloc_page_info.pad = page_info->pad;
+
+		memcpy(alloc_page_info.page_address, src, page_info->pad + len);
+		skb = gve_rx_add_frags(napi, &alloc_page_info,
+				       rx->packet_buffer_size,
+				       len, ctx);
+
+		u64_stats_update_begin(&rx->statss);
+		rx->rx_frag_copy_cnt++;
+		rx->rx_frag_alloc_cnt++;
+		u64_stats_update_end(&rx->statss);
+
+		return skb;
+	}
+
+	dst = copy_page_info->page_address + copy_page_info->page_offset;
+	memcpy(dst, src, page_info->pad + len);
+	copy_page_info->pad = page_info->pad;
+
+	skb = gve_rx_add_frags(napi, copy_page_info,
+			       rx->packet_buffer_size, len, ctx);
+	if (unlikely(!skb))
+		return NULL;
+
+	gve_dec_pagecnt_bias(copy_page_info);
+	copy_page_info->page_offset += rx->packet_buffer_size;
+	copy_page_info->page_offset &= (PAGE_SIZE - 1);
+
+	if (copy_page_info->can_flip) {
+		/* We have used both halves of this copy page, it
+		 * is time for it to go to the back of the queue.
+		 */
+		copy_page_info->can_flip = false;
+		rx->qpl_copy_pool_head++;
+		prefetch(rx->qpl_copy_pool[rx->qpl_copy_pool_head & rx->qpl_copy_pool_mask].page);
+	} else {
+		copy_page_info->can_flip = true;
+	}
+
+	u64_stats_update_begin(&rx->statss);
+	rx->rx_frag_copy_cnt++;
+	u64_stats_update_end(&rx->statss);
+
+	return skb;
+}
+
+static struct sk_buff *
+gve_rx_qpl(struct device *dev, struct net_device *netdev,
+	   struct gve_rx_ring *rx, struct gve_rx_slot_page_info *page_info,
+	   u16 len, struct napi_struct *napi,
+	   union gve_rx_data_slot *data_slot)
+{
+	struct gve_rx_ctx *ctx = &rx->ctx;
+	struct sk_buff *skb;
+
+	/* if raw_addressing mode is not enabled gvnic can only receive into
+	 * registered segments. If the buffer can't be recycled, our only
+	 * choice is to copy the data out of it so that we can return it to the
+	 * device.
+	 */
+	if (page_info->can_flip) {
+		skb = gve_rx_add_frags(napi, page_info, rx->packet_buffer_size, len, ctx);
+		/* No point in recycling if we didn't get the skb */
+		if (skb) {
+			/* Make sure that the page isn't freed. */
+			gve_dec_pagecnt_bias(page_info);
+			gve_rx_flip_buff(page_info, &data_slot->qpl_offset);
+		}
+	} else {
+		skb = gve_rx_copy_to_pool(rx, page_info, len, napi);
+	}
+	return skb;
+}
+
+static struct sk_buff *gve_rx_skb(struct gve_priv *priv, struct gve_rx_ring *rx,
+				  struct gve_rx_slot_page_info *page_info, struct napi_struct *napi,
+				  u16 len, union gve_rx_data_slot *data_slot,
+				  bool is_only_frag)
+{
+	struct net_device *netdev = priv->dev;
+	struct gve_rx_ctx *ctx = &rx->ctx;
+	struct sk_buff *skb = NULL;
+
+	if (len <= priv->rx_copybreak && is_only_frag)  {
+		/* Just copy small packets */
+		skb = gve_rx_copy(netdev, napi, page_info, len, GVE_RX_PAD);
+		if (skb) {
+			u64_stats_update_begin(&rx->statss);
+			rx->rx_copied_pkt++;
+			rx->rx_frag_copy_cnt++;
+			rx->rx_copybreak_pkt++;
+			u64_stats_update_end(&rx->statss);
+		}
+	} else {
+		int recycle = gve_rx_can_recycle_buffer(page_info);
+
+		if (unlikely(recycle < 0)) {
+			gve_schedule_reset(priv);
+			return NULL;
+		}
+		page_info->can_flip = recycle;
+		if (page_info->can_flip) {
+			u64_stats_update_begin(&rx->statss);
+			rx->rx_frag_flip_cnt++;
+			u64_stats_update_end(&rx->statss);
+		}
+
+		if (rx->data.raw_addressing) {
+			skb = gve_rx_raw_addressing(&priv->pdev->dev, netdev,
+						    page_info, len, napi,
+						    data_slot,
+						    rx->packet_buffer_size, ctx);
+		} else {
+			skb = gve_rx_qpl(&priv->pdev->dev, netdev, rx,
+					 page_info, len, napi, data_slot);
+		}
+	}
+	return skb;
+}
+
+#define GVE_PKTCONT_BIT_IS_SET(x) (GVE_RXF_PKT_CONT & (x))
+static void gve_rx(struct gve_rx_ring *rx, netdev_features_t feat,
+		   struct gve_rx_desc *desc, u32 idx,
+		   struct gve_rx_cnts *cnts)
+{
+	bool is_last_frag = !GVE_PKTCONT_BIT_IS_SET(desc->flags_seq);
+	struct gve_rx_slot_page_info *page_info;
+	u16 frag_size = be16_to_cpu(desc->len);
+	struct gve_rx_ctx *ctx = &rx->ctx;
+	union gve_rx_data_slot *data_slot;
+	struct gve_priv *priv = rx->gve;
+	struct sk_buff *skb = NULL;
+	dma_addr_t page_bus;
+	void *va;
+
+	struct napi_struct *napi = &priv->ntfy_blocks[rx->ntfy_id].napi;
+	bool is_first_frag = ctx->frag_cnt == 0;
+
+	bool is_only_frag = is_first_frag && is_last_frag;
+
+	if (unlikely(ctx->drop_pkt))
+		goto finish_frag;
+
+	if (desc->flags_seq & GVE_RXF_ERR) {
+		ctx->drop_pkt = true;
+		cnts->desc_err_pkt_cnt++;
+		napi_free_frags(napi);
+		goto finish_frag;
+	}
+
+	if (unlikely(frag_size > rx->packet_buffer_size)) {
+		netdev_warn(priv->dev, "Unexpected frag size %d, can't exceed %d, scheduling reset",
+			    frag_size, rx->packet_buffer_size);
+		ctx->drop_pkt = true;
+		napi_free_frags(napi);
+		gve_schedule_reset(rx->gve);
+		goto finish_frag;
+	}
+
+	/* Prefetch two packet buffers ahead, we will need it soon. */
+	page_info = &rx->data.page_info[(idx + 2) & rx->mask];
+	va = page_info->page_address + page_info->page_offset;
+	prefetch(page_info->page); /* Kernel page struct. */
+	prefetch(va);              /* Packet header. */
+	prefetch(va + 64);         /* Next cacheline too. */
+
+	page_info = &rx->data.page_info[idx];
+	data_slot = &rx->data.data_ring[idx];
+	page_bus = (rx->data.raw_addressing) ?
+		be64_to_cpu(data_slot->addr) - page_info->page_offset :
+		rx->data.qpl->page_buses[idx];
+	dma_sync_single_for_cpu(&priv->pdev->dev, page_bus,
+				PAGE_SIZE, DMA_FROM_DEVICE);
+	page_info->pad = is_first_frag ? GVE_RX_PAD : 0;
+	frag_size -= page_info->pad;
+
+	skb = gve_rx_skb(priv, rx, page_info, napi, frag_size,
+			 data_slot, is_only_frag);
+	if (!skb) {
+		u64_stats_update_begin(&rx->statss);
+		rx->rx_skb_alloc_fail++;
+		u64_stats_update_end(&rx->statss);
+
+		napi_free_frags(napi);
+		ctx->drop_pkt = true;
+		goto finish_frag;
+	}
+	ctx->total_size += frag_size;
+
+	if (is_first_frag) {
+		if (likely(feat & NETIF_F_RXCSUM)) {
+			/* NIC passes up the partial sum */
+			if (desc->csum)
+				skb->ip_summed = CHECKSUM_COMPLETE;
+			else
+				skb->ip_summed = CHECKSUM_NONE;
+			skb->csum = csum_unfold(desc->csum);
+		}
+
+		/* parse flags & pass relevant info up */
+		if (likely(feat & NETIF_F_RXHASH) &&
+		    gve_needs_rss(desc->flags_seq))
+			skb_set_hash(skb, be32_to_cpu(desc->rss_hash),
+				     gve_rss_type(desc->flags_seq));
+	}
+
+	if (is_last_frag) {
+		skb_record_rx_queue(skb, rx->q_num);
+		if (skb_is_nonlinear(skb))
+			napi_gro_frags(napi);
+		else
+			napi_gro_receive(napi, skb);
+		goto finish_ok_pkt;
+	}
+
+	goto finish_frag;
+
+finish_ok_pkt:
+	cnts->ok_pkt_bytes += ctx->total_size;
+	cnts->ok_pkt_cnt++;
+finish_frag:
+	ctx->frag_cnt++;
+	if (is_last_frag) {
+		cnts->total_pkt_cnt++;
+		cnts->cont_pkt_cnt += (ctx->frag_cnt > 1);
+		gve_rx_ctx_clear(ctx);
+	}
+}
+
+bool gve_rx_work_pending(struct gve_rx_ring *rx)
+{
+	struct gve_rx_desc *desc;
+	__be16 flags_seq;
+	u32 next_idx;
+
+	next_idx = rx->cnt & rx->mask;
+	desc = rx->desc.desc_ring + next_idx;
+
+	flags_seq = desc->flags_seq;
+
+	return (GVE_SEQNO(flags_seq) == rx->desc.seqno);
+}
+
+static bool gve_rx_refill_buffers(struct gve_priv *priv, struct gve_rx_ring *rx)
+{
+	int refill_target = rx->mask + 1;
+	u32 fill_cnt = rx->fill_cnt;
+
+	while (fill_cnt - rx->cnt < refill_target) {
+		struct gve_rx_slot_page_info *page_info;
+		u32 idx = fill_cnt & rx->mask;
+
+		page_info = &rx->data.page_info[idx];
+		if (page_info->can_flip) {
+			/* The other half of the page is free because it was
+			 * free when we processed the descriptor. Flip to it.
+			 */
+			union gve_rx_data_slot *data_slot =
+						&rx->data.data_ring[idx];
+
+			gve_rx_flip_buff(page_info, &data_slot->addr);
+			page_info->can_flip = 0;
+		} else {
+			/* It is possible that the networking stack has already
+			 * finished processing all outstanding packets in the buffer
+			 * and it can be reused.
+			 * Flipping is unnecessary here - if the networking stack still
+			 * owns half the page it is impossible to tell which half. Either
+			 * the whole page is free or it needs to be replaced.
+			 */
+			int recycle = gve_rx_can_recycle_buffer(page_info);
+
+			if (recycle < 0) {
+				if (!rx->data.raw_addressing)
+					gve_schedule_reset(priv);
+				return false;
+			}
+			if (!recycle) {
+				/* We can't reuse the buffer - alloc a new one*/
+				union gve_rx_data_slot *data_slot =
+						&rx->data.data_ring[idx];
+				struct device *dev = &priv->pdev->dev;
+				gve_rx_free_buffer(dev, page_info, data_slot);
+				page_info->page = NULL;
+				if (gve_rx_alloc_buffer(priv, dev, page_info,
+							data_slot)) {
+					u64_stats_update_begin(&rx->statss);
+					rx->rx_buf_alloc_fail++;
+					u64_stats_update_end(&rx->statss);
+					break;
+				}
+			}
+		}
+		fill_cnt++;
+	}
+	rx->fill_cnt = fill_cnt;
+	return true;
+}
+
+static int gve_clean_rx_done(struct gve_rx_ring *rx, int budget,
+			     netdev_features_t feat)
+{
+	struct gve_rx_ctx *ctx = &rx->ctx;
+	struct gve_priv *priv = rx->gve;
+	struct gve_rx_cnts cnts = {0};
+	struct gve_rx_desc *next_desc;
+	u32 idx = rx->cnt & rx->mask;
+	u32 work_done = 0;
+
+	struct gve_rx_desc *desc = &rx->desc.desc_ring[idx];
+
+	// Exceed budget only if (and till) the inflight packet is consumed.
+	while ((GVE_SEQNO(desc->flags_seq) == rx->desc.seqno) &&
+	       (work_done < budget || ctx->frag_cnt)) {
+		next_desc = &rx->desc.desc_ring[(idx + 1) & rx->mask];
+		prefetch(next_desc);
+
+		gve_rx(rx, feat, desc, idx, &cnts);
+
+		rx->cnt++;
+		idx = rx->cnt & rx->mask;
+		desc = &rx->desc.desc_ring[idx];
+		rx->desc.seqno = gve_next_seqno(rx->desc.seqno);
+		work_done++;
+	}
+
+	// The device will only send whole packets.
+	if (unlikely(ctx->frag_cnt)) {
+		struct napi_struct *napi = &priv->ntfy_blocks[rx->ntfy_id].napi;
+
+		napi_free_frags(napi);
+		gve_rx_ctx_clear(&rx->ctx);
+		netdev_warn(priv->dev, "Unexpected seq number %d with incomplete packet, expected %d, scheduling reset",
+			    GVE_SEQNO(desc->flags_seq), rx->desc.seqno);
+		gve_schedule_reset(rx->gve);
+	}
+
+	if (!work_done && rx->fill_cnt - rx->cnt > rx->db_threshold)
+		return 0;
+
+	if (work_done) {
+		u64_stats_update_begin(&rx->statss);
+		rx->rpackets += cnts.ok_pkt_cnt;
+		rx->rbytes += cnts.ok_pkt_bytes;
+		rx->rx_cont_packet_cnt += cnts.cont_pkt_cnt;
+		rx->rx_desc_err_dropped_pkt += cnts.desc_err_pkt_cnt;
+		u64_stats_update_end(&rx->statss);
+	}
+
+	/* restock ring slots */
+	if (!rx->data.raw_addressing) {
+		/* In QPL mode buffs are refilled as the desc are processed */
+		rx->fill_cnt += work_done;
+	} else if (rx->fill_cnt - rx->cnt <= rx->db_threshold) {
+		/* In raw addressing mode buffs are only refilled if the avail
+		 * falls below a threshold.
+		 */
+		if (!gve_rx_refill_buffers(priv, rx))
+			return 0;
+
+		/* If we were not able to completely refill buffers, we'll want
+		 * to schedule this queue for work again to refill buffers.
+		 */
+		if (rx->fill_cnt - rx->cnt <= rx->db_threshold) {
+			gve_rx_write_doorbell(priv, rx);
+			return budget;
+		}
+	}
+
+	gve_rx_write_doorbell(priv, rx);
+	return cnts.total_pkt_cnt;
+}
+
+int gve_rx_poll(struct gve_notify_block *block, int budget)
+{
+	struct gve_rx_ring *rx = block->rx;
+	netdev_features_t feat;
+	int work_done = 0;
+
+	feat = block->napi.dev->features;
+
+	/* If budget is 0, do all the work */
+	if (budget == 0)
+		budget = INT_MAX;
+
+	if (budget > 0)
+		work_done = gve_clean_rx_done(rx, budget, feat);
+
+	return work_done;
+}