net: ena: Add dynamic recycling mechanism for rx buffers

The current implementation allocates page-sized rx buffers.
As traffic may consist of different types and sizes of packets,
in various cases, buffers are not fully used.

This change (Dynamic RX Buffers - DRB) uses part of the allocated rx
page needed for the incoming packet, and returns the rest of the
unused page to be used again as an rx buffer for future packets.
A threshold of 2K for unused space has been set in order to declare
whether the remainder of the page can be reused again as an rx buffer.

As a page may be reused, dma_sync_single_for_cpu() is added in order
to sync the memory to the CPU side after it was owned by the HW.
In addition, when the rx page can no longer be reused, it is being
unmapped using dma_page_unmap(), which implicitly syncs and then
unmaps the entire page. In case the kernel still handles the skbs
pointing to the previous buffers from that rx page, it may access
garbage pointers, caused by the implicit sync overwriting them.
The implicit dma sync is removed by replacing dma_page_unmap() with
dma_unmap_page_attrs() with DMA_ATTR_SKIP_CPU_SYNC flag.

The functionality is disabled for XDP traffic to avoid handling
several descriptors per packet.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20230612121448.28829-1-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: ena: Add capabilities field with support for ENI stats capability

This bitmask field indicates what capabilities are supported by the
device.

The capabilities field differs from the 'supported_features' field which
indicates what sub-commands for the set/get feature commands are
supported. The sub-commands are specified in the 'feature_id' field of
the 'ena_admin_set_feat_cmd' struct in the following way:

struct ena_admin_set_feat_cmd cmd;

cmd.aq_common_descriptor.opcode = ENA_ADMIN_SET_FEATURE;
cmd.feat_common.feature_

The 'capabilities' field, on the other hand, specifies different
capabilities of the device. For example, whether the device supports
querying of ENI stats.

Also add an enumerator which contains all the capabilities. The
first added capability macro is for ENI stats feature.

Capabilities are queried along with the other device attributes (in
ena_com_get_dev_attr_feat()) during device initialization and are stored
in the ena_com_dev struct. They can be later queried using the
ena_com_get_cap() helper function.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: ena: Remove unused code

The ENA_DEFAULT_MIN_RX_BUFF_ALLOC_SIZE macro,
ena_xdp_queues_present() function and SUSPEND_RESUME enums aren't used
in the driver, and so not needed.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Gal Pressman <galpress@amazon.com>
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: Change RSS related macros and variables names

The formal name changes to "ENA_ADMIN_RSS_INDIRECTION_TABLE_CONFIG".
Indirection is the ability to reference "something" using "something else"
instead of the value itself.
Indirection table, as the name implies, is the ability to reference
CPU/Queue value using hash-to-CPU table instead of CPU/Queue itself.

This patch renames the variable keys_num, which describes the number of
words in the RSS hash key, to key_parts which makes its purpose clearer
in RSS context.

Signed-off-by: Amit Bernstein <amitbern@amazon.com>
Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: Capitalize all log strings and improve code readability

Capitalize all log strings printed by the ena driver to make their
format uniform across it.

Also fix indentation, spelling mistakes and comments to improve code
readability. This also includes adding comments to macros/enums whose
purpose might be difficult to understand.
Separate some code into functions to make it easier to understand the
purpose of these lines.

Signed-off-by: Amit Bernstein <amitbern@amazon.com>
Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: Change license into format to SPDX in all files

All ena files should now use SPDX format in their license string. This
doesn't change the license of the files, but rather states the same
license in fewer words.

Also update the license years in some of the files.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: ethtool: Add new device statistics

The new metrics provide granular visibility along multiple network
dimensions and enable troubleshooting and remediation of issues caused
by instances exceeding network performance allowances.

The new statistics can be queried using ethtool command.

Signed-off-by: Guy Tzalik <gtzalik@amazon.com>
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: support new LLQ acceleration mode

New devices add a new hardware acceleration engine, which adds some
restrictions to the driver.
Metadata descriptor must be present for each packet and the maximum
burst size between two doorbells is now limited to a number
advertised by the device.

This patch adds:
1. A handshake protocol between the driver and the device, so the
device will enable the accelerated queues only when both sides
support it.

2. The driver support for the new acceleration engine:
2.1. Send metadata descriptor for each Tx packet.
2.2. Limit the number of packets sent between doorbells.(*)

(*) A previous driver implementation of this feature was comitted in
commit 05d62ca218f8 ("net: ena: add handling of llq max tx burst size")
however the design of the interface between the driver and device
changed since then. This change is reflected in this commit.

Signed-off-by: Netanel Belgazal <netanel@amazon.com>
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: enable support of rss hash key and function changes

Add the rss_configurable_function_key bit to driver_supported_feature.

This bit tells the device that the driver in question supports the
retrieving and updating of RSS function and hash key, and therefore
the device should allow RSS function and key manipulation.

This commit turns on device support for hash key and RSS function
management. Without this commit this feature is turned off at the
device and appears to the user as unsupported.

This commit concludes the following series of already merged commits:
commit 0af3c4e2eab8 ("net: ena: changes to RSS hash key allocation")
commit c1bd17e51c71 ("net: ena: change default RSS hash function to Toeplitz")
commit f66c2ea3b18a ("net: ena: allow setting the hash function without changing the key")
commit e9a1de378dd4 ("net: ena: fix error returning in ena_com_get_hash_function()")
commit 80f8443fcdaa ("net: ena: avoid unnecessary admin command when RSS function set fails")
commit 6a4f7dc82d1e ("net: ena: rss: do not allocate key when not supported")
commit 0d1c3de7b8c7 ("net: ena: fix incorrect default RSS key")

The above commits represent the last part of the implementation of
this feature, and with them merged the feature can be enabled
in the device.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: add support for traffic mirroring

Add support for traffic mirroring, where the hardware reads the
buffer from the instance memory directly.

Traffic Mirroring needs access to the rx buffers in the instance.
To have this access, this patch:
1. Changes the code to map and unmap the rx buffers bidirectionally.
2. Enables the relevant bit in driver_supported_features to indicate
to the FW that this driver supports traffic mirroring.

Rx completion is not generated until mirroring is done to avoid
the situation where the driver changes the buffer before it is
mirrored.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: cosmetic: fix spacing issues

1. Add leading and trailing spaces to several comments for better
readability
2. Make tabs and spaces uniform in enum defines in ena_admin_defs.h

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: add support for the rx offset feature

Newer ENA devices can write data to rx buffers with an offset
from the beginning of the buffer.

This commit adds support for this feature in the driver.

Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: add support for reporting of packet drops

1. Add support for getting tx drops from the device and saving them
in the driver.
2. Report tx via netdev stats.

Signed-off-by: Igor Chauskin <igorch@amazon.com>
Signed-off-by: Guy Tzalik <gtzalik@amazon.com>
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: enable the interrupt_moderation in driver_supported_features

Add driver_supported_features to host_host info which is a new API used to
communicate to the device which features are supported by the driver.

Add the interrupt_moderation bit to host_info->driver_supported_features
and enable it to signal the device that this driver supports interrupt
moderation properly.

Reserved bits are for features implemented in the future

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Revert "net: ena: ethtool: add extra properties retrieval via get_priv_flags"

This reverts commit 315c28d2b714 ("net: ena: ethtool: add extra properties retrieval via get_priv_flags").

As discussed at netconf and on the mailing list we can't allow
for the the abuse of private flags for exposing arbitrary device
labels.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: add MAX_QUEUES_EXT get feature admin command

Add a new admin command to support different queue size for Tx/Rx
queues (the change also support different SQ/CQ sizes)

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: ethtool: add extra properties retrieval via get_priv_flags

This commit adds a mechanism for exposing different device
properties via ethtool's priv_flags. The strings are provided
by the device and copied to user space through the driver.

In this commit we:

Add commands, structs and defines necessary for handling
extra properties

Add functions for:
Allocation/destruction of a buffer for extra properties strings.
Retreival of extra properties strings and flags from the network device.

Handle the allocation of a buffer for extra properties strings.

* Initialize buffer with extra properties strings from the
network device at driver startup.

Use ethtool's get_priv_flags to expose extra properties of
the ENA device

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: add handling of llq max tx burst size

There is a maximum TX burst size that the ENA device can handle.
It is exposed by the device to the driver and the driver
needs to comply with it to avoid bugs.

In this commit we:
1. Add ena_com_is_doorbell_needed(), which calculates the number of
llq entries that will be used to hold a packet, and will return
true if they exceed the number of allowed entries in a burst.
If the function returns true, a doorbell needs to be invoked
to send this packet in the next burst.

2. Follow the available entries in the current burst:
- Every doorbell a new burst begins
- With each write of an llq entry, the available entries in the
current burst are decreased by 1.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: fix indentations in ena_defs for better readability

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: introduce Low Latency Queues data structures according to ENA spec

Low Latency Queues(LLQ) allow usage of device's memory for descriptors
and headers. Such queues decrease processing time since data is already
located on the device when driver rings the doorbell.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: complete host info to match latest ENA spec

Add new fields and definitions to host info and fill them
according to the latest ENA spec version.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: add new admin define for future support of IPv6 RSS

Signed-off-by: Netanel Belgazal <netanel@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: add hardware hints capability to the driver

With this patch, ENA device can update the ena driver about
the desired timeout values:
These values are part of the "hardware hints" which are transmitted
to the driver as Asynchronous event through ENA async
event notification queue.

In case the ENA device does not support this capability,
the driver will use its own default values.

Signed-off-by: Netanel Belgazal <netanel@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ena: refactor ena_get_stats64 to be atomic context safe

ndo_get_stat64() can be called from atomic context, but the current
implementation sends an admin command to retrieve the statistics from
the device. This admin command can sleep.

This patch re-factors the implementation of ena_get_stats64() to use
the {rx,tx}bytes/count from the driver's inner counters, and to obtain
the rx drop counter from the asynchronous keep alive (heart bit)
event.

Signed-off-by: Netanel Belgazal <netanel@annapurnalabs.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ena: fix ethtool RSS flow configuration

ena_flow_data_to_flow_hash and ena_flow_hash_to_flow_type
treat the ena_flow_hash_to_flow_type enum as power of two values.

Change the values of ena_admin_flow_hash_fields to be power of two values.

This bug effect the ethtool set/get rxnfc.
ethtool will report wrong values hash fields for get and will
configure wrong hash fields in set.

Signed-off-by: Netanel Belgazal <netanel@annapurnalabs.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)

This is a driver for the ENA family of networking devices.

Signed-off-by: Netanel Belgazal <netanel@annapurnalabs.com>
Signed-off-by: David S. Miller <davem@davemloft.net>