Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking updates from David Miller:

 1) New ipset extensions for matching on destination MAC addresses, from
    Stefano Brivio.

 2) Add ipv4 ttl and tos, plus ipv6 flow label and hop limit offloads to
    nfp driver. From Stefano Brivio.

 3) Implement GRO for plain UDP sockets, from Paolo Abeni.

 4) Lots of work from Michał Mirosław to eliminate the VLAN_TAG_PRESENT
    bit so that we could support the entire vlan_tci value.

 5) Rework the IPSEC policy lookups to better optimize more usecases,
    from Florian Westphal.

 6) Infrastructure changes eliminating direct manipulation of SKB lists
    wherever possible, and to always use the appropriate SKB list
    helpers. This work is still ongoing...

 7) Lots of PHY driver and state machine improvements and
    simplifications, from Heiner Kallweit.

 8) Various TSO deferral refinements, from Eric Dumazet.

 9) Add ntuple filter support to aquantia driver, from Dmitry Bogdanov.

10) Batch dropping of XDP packets in tuntap, from Jason Wang.

11) Lots of cleanups and improvements to the r8169 driver from Heiner
    Kallweit, including support for ->xmit_more. This driver has been
    getting some much needed love since he started working on it.

12) Lots of new forwarding selftests from Petr Machata.

13) Enable VXLAN learning in mlxsw driver, from Ido Schimmel.

14) Packed ring support for virtio, from Tiwei Bie.

15) Add new Aquantia AQtion USB driver, from Dmitry Bezrukov.

16) Add XDP support to dpaa2-eth driver, from Ioana Ciocoi Radulescu.

17) Implement coalescing on TCP backlog queue, from Eric Dumazet.

18) Implement carrier change in tun driver, from Nicolas Dichtel.

19) Support msg_zerocopy in UDP, from Willem de Bruijn.

20) Significantly improve garbage collection of neighbor objects when
    the table has many PERMANENT entries, from David Ahern.

21) Remove egdev usage from nfp and mlx5, and remove the facility
    completely from the tree as it no longer has any users. From Oz
    Shlomo and others.

22) Add a NETDEV_PRE_CHANGEADDR so that drivers can veto the change and
    therefore abort the operation before the commit phase (which is the
    NETDEV_CHANGEADDR event). From Petr Machata.

23) Add indirect call wrappers to avoid retpoline overhead, and use them
    in the GRO code paths. From Paolo Abeni.

24) Add support for netlink FDB get operations, from Roopa Prabhu.

25) Support bloom filter in mlxsw driver, from Nir Dotan.

26) Add SKB extension infrastructure. This consolidates the handling of
    the auxiliary SKB data used by IPSEC and bridge netfilter, and is
    designed to support the needs to MPTCP which could be integrated in
    the future.

27) Lots of XDP TX optimizations in mlx5 from Tariq Toukan.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1845 commits)
  net: dccp: fix kernel crash on module load
  drivers/net: appletalk/cops: remove redundant if statement and mask
  bnx2x: Fix NULL pointer dereference in bnx2x_del_all_vlans() on some hw
  net/net_namespace: Check the return value of register_pernet_subsys()
  net/netlink_compat: Fix a missing check of nla_parse_nested
  ieee802154: lowpan_header_create check must check daddr
  net/mlx4_core: drop useless LIST_HEAD
  mlxsw: spectrum: drop useless LIST_HEAD
  net/mlx5e: drop useless LIST_HEAD
  iptunnel: Set tun_flags in the iptunnel_metadata_reply from src
  net/mlx5e: fix semicolon.cocci warnings
  staging: octeon: fix build failure with XFRM enabled
  net: Revert recent Spectre-v1 patches.
  can: af_can: Fix Spectre v1 vulnerability
  packet: validate address length if non-zero
  nfc: af_nfc: Fix Spectre v1 vulnerability
  phonet: af_phonet: Fix Spectre v1 vulnerability
  net: core: Fix Spectre v1 vulnerability
  net: minor cleanup in skb_ext_add()
  net: drop the unused helper skb_ext_get()
  ...

1 files changed, 305 insertions, 0 deletions

diff --git a/Documentation/networking/device_drivers/amazon/ena.txt b/Documentation/networking/device_drivers/amazon/ena.txt
new file mode 100644
index 000000000000..2b4b6f57e549
--- /dev/null
+++ b/Documentation/networking/device_drivers/amazon/ena.txt
@@ -0,0 +1,305 @@
+Linux kernel driver for Elastic Network Adapter (ENA) family:
+=============================================================
+
+Overview:
+=========
+ENA is a networking interface designed to make good use of modern CPU
+features and system architectures.
+
+The ENA device exposes a lightweight management interface with a
+minimal set of memory mapped registers and extendable command set
+through an Admin Queue.
+
+The driver supports a range of ENA devices, is link-speed independent
+(i.e., the same driver is used for 10GbE, 25GbE, 40GbE, etc.), and has
+a negotiated and extendable feature set.
+
+Some ENA devices support SR-IOV. This driver is used for both the
+SR-IOV Physical Function (PF) and Virtual Function (VF) devices.
+
+ENA devices enable high speed and low overhead network traffic
+processing by providing multiple Tx/Rx queue pairs (the maximum number
+is advertised by the device via the Admin Queue), a dedicated MSI-X
+interrupt vector per Tx/Rx queue pair, adaptive interrupt moderation,
+and CPU cacheline optimized data placement.
+
+The ENA driver supports industry standard TCP/IP offload features such
+as checksum offload and TCP transmit segmentation offload (TSO).
+Receive-side scaling (RSS) is supported for multi-core scaling.
+
+The ENA driver and its corresponding devices implement health
+monitoring mechanisms such as watchdog, enabling the device and driver
+to recover in a manner transparent to the application, as well as
+debug logs.
+
+Some of the ENA devices support a working mode called Low-latency
+Queue (LLQ), which saves several more microseconds.
+
+Supported PCI vendor ID/device IDs:
+===================================
+1d0f:0ec2 - ENA PF
+1d0f:1ec2 - ENA PF with LLQ support
+1d0f:ec20 - ENA VF
+1d0f:ec21 - ENA VF with LLQ support
+
+ENA Source Code Directory Structure:
+====================================
+ena_com.[ch]      - Management communication layer. This layer is
+                    responsible for the handling all the management
+                    (admin) communication between the device and the
+                    driver.
+ena_eth_com.[ch]  - Tx/Rx data path.
+ena_admin_defs.h  - Definition of ENA management interface.
+ena_eth_io_defs.h - Definition of ENA data path interface.
+ena_common_defs.h - Common definitions for ena_com layer.
+ena_regs_defs.h   - Definition of ENA PCI memory-mapped (MMIO) registers.
+ena_netdev.[ch]   - Main Linux kernel driver.
+ena_syfsfs.[ch]   - Sysfs files.
+ena_ethtool.c     - ethtool callbacks.
+ena_pci_id_tbl.h  - Supported device IDs.
+
+Management Interface:
+=====================
+ENA management interface is exposed by means of:
+- PCIe Configuration Space
+- Device Registers
+- Admin Queue (AQ) and Admin Completion Queue (ACQ)
+- Asynchronous Event Notification Queue (AENQ)
+
+ENA device MMIO Registers are accessed only during driver
+initialization and are not involved in further normal device
+operation.
+
+AQ is used for submitting management commands, and the
+results/responses are reported asynchronously through ACQ.
+
+ENA introduces a very small set of management commands with room for
+vendor-specific extensions. Most of the management operations are
+framed in a generic Get/Set feature command.
+
+The following admin queue commands are supported:
+- Create I/O submission queue
+- Create I/O completion queue
+- Destroy I/O submission queue
+- Destroy I/O completion queue
+- Get feature
+- Set feature
+- Configure AENQ
+- Get statistics
+
+Refer to ena_admin_defs.h for the list of supported Get/Set Feature
+properties.
+
+The Asynchronous Event Notification Queue (AENQ) is a uni-directional
+queue used by the ENA device to send to the driver events that cannot
+be reported using ACQ. AENQ events are subdivided into groups. Each
+group may have multiple syndromes, as shown below
+
+The events are:
+	Group			Syndrome
+	Link state change	- X -
+	Fatal error		- X -
+	Notification		Suspend traffic
+	Notification		Resume traffic
+	Keep-Alive		- X -
+
+ACQ and AENQ share the same MSI-X vector.
+
+Keep-Alive is a special mechanism that allows monitoring of the
+device's health. The driver maintains a watchdog (WD) handler which,
+if fired, logs the current state and statistics then resets and
+restarts the ENA device and driver. A Keep-Alive event is delivered by
+the device every second. The driver re-arms the WD upon reception of a
+Keep-Alive event. A missed Keep-Alive event causes the WD handler to
+fire.
+
+Data Path Interface:
+====================
+I/O operations are based on Tx and Rx Submission Queues (Tx SQ and Rx
+SQ correspondingly). Each SQ has a completion queue (CQ) associated
+with it.
+
+The SQs and CQs are implemented as descriptor rings in contiguous
+physical memory.
+
+The ENA driver supports two Queue Operation modes for Tx SQs:
+- Regular mode
+  * In this mode the Tx SQs reside in the host's memory. The ENA
+    device fetches the ENA Tx descriptors and packet data from host
+    memory.
+- Low Latency Queue (LLQ) mode or "push-mode".
+  * In this mode the driver pushes the transmit descriptors and the
+    first 128 bytes of the packet directly to the ENA device memory
+    space. The rest of the packet payload is fetched by the
+    device. For this operation mode, the driver uses a dedicated PCI
+    device memory BAR, which is mapped with write-combine capability.
+
+The Rx SQs support only the regular mode.
+
+Note: Not all ENA devices support LLQ, and this feature is negotiated
+      with the device upon initialization. If the ENA device does not
+      support LLQ mode, the driver falls back to the regular mode.
+
+The driver supports multi-queue for both Tx and Rx. This has various
+benefits:
+- Reduced CPU/thread/process contention on a given Ethernet interface.
+- Cache miss rate on completion is reduced, particularly for data
+  cache lines that hold the sk_buff structures.
+- Increased process-level parallelism when handling received packets.
+- Increased data cache hit rate, by steering kernel processing of
+  packets to the CPU, where the application thread consuming the
+  packet is running.
+- In hardware interrupt re-direction.
+
+Interrupt Modes:
+================
+The driver assigns a single MSI-X vector per queue pair (for both Tx
+and Rx directions). The driver assigns an additional dedicated MSI-X vector
+for management (for ACQ and AENQ).
+
+Management interrupt registration is performed when the Linux kernel
+probes the adapter, and it is de-registered when the adapter is
+removed. I/O queue interrupt registration is performed when the Linux
+interface of the adapter is opened, and it is de-registered when the
+interface is closed.
+
+The management interrupt is named:
+   ena-mgmnt@pci:<PCI domain:bus:slot.function>
+and for each queue pair, an interrupt is named:
+   <interface name>-Tx-Rx-<queue index>
+
+The ENA device operates in auto-mask and auto-clear interrupt
+modes. That is, once MSI-X is delivered to the host, its Cause bit is
+automatically cleared and the interrupt is masked. The interrupt is
+unmasked by the driver after NAPI processing is complete.
+
+Interrupt Moderation:
+=====================
+ENA driver and device can operate in conventional or adaptive interrupt
+moderation mode.
+
+In conventional mode the driver instructs device to postpone interrupt
+posting according to static interrupt delay value. The interrupt delay
+value can be configured through ethtool(8). The following ethtool
+parameters are supported by the driver: tx-usecs, rx-usecs
+
+In adaptive interrupt moderation mode the interrupt delay value is
+updated by the driver dynamically and adjusted every NAPI cycle
+according to the traffic nature.
+
+By default ENA driver applies adaptive coalescing on Rx traffic and
+conventional coalescing on Tx traffic.
+
+Adaptive coalescing can be switched on/off through ethtool(8)
+adaptive_rx on|off parameter.
+
+The driver chooses interrupt delay value according to the number of
+bytes and packets received between interrupt unmasking and interrupt
+posting. The driver uses interrupt delay table that subdivides the
+range of received bytes/packets into 5 levels and assigns interrupt
+delay value to each level.
+
+The user can enable/disable adaptive moderation, modify the interrupt
+delay table and restore its default values through sysfs.
+
+The rx_copybreak is initialized by default to ENA_DEFAULT_RX_COPYBREAK
+and can be configured by the ETHTOOL_STUNABLE command of the
+SIOCETHTOOL ioctl.
+
+SKB:
+The driver-allocated SKB for frames received from Rx handling using
+NAPI context. The allocation method depends on the size of the packet.
+If the frame length is larger than rx_copybreak, napi_get_frags()
+is used, otherwise netdev_alloc_skb_ip_align() is used, the buffer
+content is copied (by CPU) to the SKB, and the buffer is recycled.
+
+Statistics:
+===========
+The user can obtain ENA device and driver statistics using ethtool.
+The driver can collect regular or extended statistics (including
+per-queue stats) from the device.
+
+In addition the driver logs the stats to syslog upon device reset.
+
+MTU:
+====
+The driver supports an arbitrarily large MTU with a maximum that is
+negotiated with the device. The driver configures MTU using the
+SetFeature command (ENA_ADMIN_MTU property). The user can change MTU
+via ip(8) and similar legacy tools.
+
+Stateless Offloads:
+===================
+The ENA driver supports:
+- TSO over IPv4/IPv6
+- TSO with ECN
+- IPv4 header checksum offload
+- TCP/UDP over IPv4/IPv6 checksum offloads
+
+RSS:
+====
+- The ENA device supports RSS that allows flexible Rx traffic
+  steering.
+- Toeplitz and CRC32 hash functions are supported.
+- Different combinations of L2/L3/L4 fields can be configured as
+  inputs for hash functions.
+- The driver configures RSS settings using the AQ SetFeature command
+  (ENA_ADMIN_RSS_HASH_FUNCTION, ENA_ADMIN_RSS_HASH_INPUT and
+  ENA_ADMIN_RSS_REDIRECTION_TABLE_CONFIG properties).
+- If the NETIF_F_RXHASH flag is set, the 32-bit result of the hash
+  function delivered in the Rx CQ descriptor is set in the received
+  SKB.
+- The user can provide a hash key, hash function, and configure the
+  indirection table through ethtool(8).
+
+DATA PATH:
+==========
+Tx:
+---
+end_start_xmit() is called by the stack. This function does the following:
+- Maps data buffers (skb->data and frags).
+- Populates ena_buf for the push buffer (if the driver and device are
+  in push mode.)
+- Prepares ENA bufs for the remaining frags.
+- Allocates a new request ID from the empty req_id ring. The request
+  ID is the index of the packet in the Tx info. This is used for
+  out-of-order TX completions.
+- Adds the packet to the proper place in the Tx ring.
+- Calls ena_com_prepare_tx(), an ENA communication layer that converts
+  the ena_bufs to ENA descriptors (and adds meta ENA descriptors as
+  needed.)
+  * This function also copies the ENA descriptors and the push buffer
+    to the Device memory space (if in push mode.)
+- Writes doorbell to the ENA device.
+- When the ENA device finishes sending the packet, a completion
+  interrupt is raised.
+- The interrupt handler schedules NAPI.
+- The ena_clean_tx_irq() function is called. This function handles the
+  completion descriptors generated by the ENA, with a single
+  completion descriptor per completed packet.
+  * req_id is retrieved from the completion descriptor. The tx_info of
+    the packet is retrieved via the req_id. The data buffers are
+    unmapped and req_id is returned to the empty req_id ring.
+  * The function stops when the completion descriptors are completed or
+    the budget is reached.
+
+Rx:
+---
+- When a packet is received from the ENA device.
+- The interrupt handler schedules NAPI.
+- The ena_clean_rx_irq() function is called. This function calls
+  ena_rx_pkt(), an ENA communication layer function, which returns the
+  number of descriptors used for a new unhandled packet, and zero if
+  no new packet is found.
+- Then it calls the ena_clean_rx_irq() function.
+- ena_eth_rx_skb() checks packet length:
+  * If the packet is small (len < rx_copybreak), the driver allocates
+    a SKB for the new packet, and copies the packet payload into the
+    SKB data buffer.
+    - In this way the original data buffer is not passed to the stack
+      and is reused for future Rx packets.
+  * Otherwise the function unmaps the Rx buffer, then allocates the
+    new SKB structure and hooks the Rx buffer to the SKB frags.
+- The new SKB is updated with the necessary information (protocol,
+  checksum hw verify result, etc.), and then passed to the network
+  stack, using the NAPI interface function napi_gro_receive().