Currently, the driver had 2 global locks - one was sx lock used for
up/down synchronization and the second one was mutex, which was used
for link configuration and timer service callout.
It is better to have single lock for that. We cannot use mutex, as it
can sleep and cause witness errors in up/down configuration, so sx lock
seems to be the only choice.
Callout cannot use sx lock, but the timer service is MP safe, so we just
need to avoid race between ena_down() and ena_detach(). It can be
avoided by acquiring sx lock.
Simple macros were added that are encapsulating implementation of the
lock and makes the code cleaner.
Submitted by: Michal Krawczyk <mk@semihalf.com>
Obtained from: Semihalf
Sponsored by: Amazon, Inc.
As the reset triggering is no longer a simple macro that was just
setting appropriate flag, the new function for triggering reset was
added. It improves code readability a lot, as we are avoiding additional
indentation.
Submitted by: Michal Krawczyk <mk@semihalf.com>
Obtained from: Semihalf
Sponsored by: Amazon, Inc.
* Removed adaptive interrupt moderation (not suported on FreeBSD).
* Use ena_com_free_q_entries instead of ena_com_free_desc.
* Don't use ENA_MEM_FREE outside of the ena_com.
* Don't use barriers before calling doorbells as it's already done in
the HAL.
* Add function that generates random RSS key, common for all driver's
interfaces.
* Change admin stats sysctls to U64.
Submitted by: Michal Krawczyk <mk@semihalf.com>
Obtained from: Semihalf
Sponsored by: Amazon, Inc.
In NETMAP mode not all queues need to be allocated to NETMAP. Some of
them could be left to the kernel. Configuration is managed by the flags
nr_mode and nr_pending_mode provided per each NETMAP kring.
ENA driver checks those flags and perform proper rings initialization.
Differential Revision: https://reviews.freebsd.org/D21937
Submitted by: Rafal Kozik <rk@semihalf.com>
Michal Krawczyk <mk@semihalf.com>
Obtained from: Semihalf
Sponsored by: Amazon, Inc.
Two new tables are added to ena_tx_buffer structure:
* netmap_map_seg stores DMA mapping structures,
* netmap_buf_idx stores buff indexes taken from the slots.
When Tx resources are being set, the new mapping structures are created
and netmap Tx rings are being reset.
When Tx resources are being released, used netmap bufs are unmapped from
DMA and then mapping structures are destroyed.
When Tx interrupt occurrs, ena_netmap_tx_irq is called.
ena_netmap_txsync callback signalizes that there are new packets which
should be transmitted.
First, it fills ena_netmap_ctx. Then it performs two actions:
* ena_netmap_tx_frames moves packets from netmap ring to NIC,
* ena_netmap_tx_cleanup restores buffers from NIC and gives them back
to the userspace app.
0 is returned in case of Tx error that could be handled by the driver.
ena_netmap_tx_frames checks if there are packets ready for transmission.
Then, for each of them, ena_netmap_tx_frame is called. If error occurs,
transmitting is stopped, but if the error was cause due to HW ring being
full, information about that is not propagated to the userspace app.
When all packets are ready, doorbell is written to NIC and netmap ring
state is updated.
Parsing of one packet is done by the ena_netmap_tx_frame function.
First, it checks if number of slots does not exceed NIC limit. Invalid
packets are being dropped and the error is propagated to the upper
layer. As each netmap buffer has equal size, which is typically greater
then 2KiB, there shouldn't be any packets which contain too many slots.
Then, the ena_com_tx_ctx structure is being filled. As netmap does not
support any hardware offloads, ena_com_tx_meta structure is set to zero.
After that, ena_netmap_map_slots maps all memory slots for DMA.
If the device works in the LLQ mode, the push header is being determined
by checking if the header fits within the first socket.
If so, the portion of data is being copied directly from the slot.
In other case, the data is copied to the intermediate buffer.
First slots are treated the same as as the others, because DMA mapping
has no impact on LLQ mode. Index of each netmap buffer is taken from
slot and stored in netmap_buf_idx array. In case of mapping error,
memory is unmapped and packets are put back to the netmap ring.
ena_netmap_tx_cleanup performs out of order cleanup of sent buffers.
First, req_id is taken and is validated. As validate_tx_req_id from
ena.c is specific to kernels mbuf, another implementation is provided.
Each req_id is cleaned up by ena_netmap_tx_clean_one function. Buffers
are being unmaped from DMA and put back to netmap ring. In the end,
state of netmap and NIC rings are being updated.
Differential Revision: https://reviews.freebsd.org/D21936
Submitted by: Rafal Kozik <rk@semihalf.com>
Michal Krawczyk <mk@semihalf.com>
Obtained from: Semihalf
Sponsored by: Amazon, Inc.
Most of code used for Rx ring initialization could be reused in NETMAP.
Reset of NETMAP ring and new alloc method was added. Driver decides if
use kernels mbufs or NETMAPs slots based on IFCAP_NETMAP flag. It
allows to reuse ena_refill_rx_bufs, which provides proper handling of
Rx out of order completion.
ena_netmap_alloc_rx_slot takes exactly the same arguments as
ena_alloc_rx_mbuf, but instead of allocating one mbuf it takes one slot
from NETMAP ring. Based on queue id proper netmap_ring is found. As
NETMAP provides the "partial opening" feature not all of the rings are
avaiable. Not used points to invalid ring. If there is available slot,
it is taken from the ring. Its buffer is mapped to DMA and its index is
stored in ena_rx_buffer field in ena_rx_buffer structure. Then ena_buf
is filled with addresses and ring state is updated.
Cleanup is handled by ena_netmap_free_rx_slot. It unmaps DMA and returns
buffer to ring. As we could not return more bufs than we have taken and
we should not override occupied slots, buf_index should be 0. It is
being checked by assertion.
ena_netmap_rxsync callback puts received packets back to NETMAP ring and
passes them to user space by updating ring pointers. First it fills
ena_netmap_ctx.
Then it performs two actions:
* ena_netmap_rx_frames moves received frames from NIC to NETMAP ring,
* ena_netmap_rx_cleanup fills NIC ring with slots released by userspace
app.
In case of Rx error that could be handled by NIC driver (for example by
performing reset) rx sync should return 0.
ena_netmap_rx_frames first checks if NETMAP ring is in consistent
state and then in the loop receives new frames. When all available
frames are taken nr_hwtail is updated.
Receiving one frame is handled by ena_netmap_rx_frame. If no error
occurrs, each Descriptor is loaded by ena_netmap_rx_load_desc function.
If packets take more than one segments NS_MOREFRAG flag must be set in
all, but not last slot. In case of wrong req_id packet is removed from
NETMAP ring. If packet is successful received counters are updated.
Refiling of NIC ring is performed by ena_netmap_rx_cleanup function.
It calculates number of available slots and call ena_refill_rx_bufs with
proper number.
Differential Revision: https://reviews.freebsd.org/D21935
Submitted by: Rafal Kozik <rk@semihalf.com>
Michal Krawczyk <mk@semihalf.com>
Obtained from: Semihalf
Sponsored by: Amazon, Inc.
Mock implementation of NETMAP routines is located in ena_netmap.c/.h
files. All code is protected under the DEV_NETMAP macro. Makefile was
updated with files and flag.
As ENA driver provide own implementations of (un)likely it must be
undefined before including NETMAP headers.
ena_netmap_attach function is called on the end of NIC attach. It fills
structure with NIC configuration and callbacks. Then provides it to
netmap_attach. Similarly netmap_detach is called during ena_detach.
Three callbacks are used.
nm_register is implemented by ena_netmap_reg. It is called when user
space application open or close NIC in NETMAP mode. Current action is
recognized based on onoff parameter: true means on and false off. As
NICs rings need to be reconfigured ena_down and ena_up are reused.
When user space application wants to receive new packets from NIC
nm_rxsync is called, and when there are new packets ready for Tx
nm_txsync is called.
Differential Revision: https://reviews.freebsd.org/D21934
Submitted by: Rafal Kozik <rk@semihalf.com>
Michal Krawczyk <mk@semihalf.com>
Obtained from: Semihalf
Sponsored by: Amazon, Inc.
