Implement .get_ringparam (ethtool -g) functionality
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The vnic server reports the statistics buffer in big endian format and must
be converted to cpu endian in order to be displayed correctly on little
endian lpars.
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add counters to report number of packets, bytes, and dropped packets for
each transmit queue and number of packets, bytes, and interrupts for each
receive queue. Modify ethtool callbacks to report the new statistics.
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On resume, the ibmvnic driver will fail to resume normal operation.
The main crq gets closed on suspend by the vnic server and doesn't get
reopened again as the interrupt for the transport event that would reset
the main crq comes in after the driver has been suspended.

This patch resolves the issue by removing the calls to kick the receive
interrupts handlers and instead directly invoking the main crq interrupt
handler. This will ensure that we see the transport event necessary to
properly resume the driver.
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

dev_pm_ops are not supposed to change at runtime. All functions
working with dev_pm_ops provided by <linux/device.h> work with const
dev_pm_ops. So mark the non-const structs as const.

File size before:
   text	   data	    bss	    dec	    hex	filename
  15426	   1256	      0	  16682	   412a	drivers/net/ethernet/ibm/ibmveth.o

File size After adding 'const':
   text	   data	    bss	    dec	    hex	filename
  15618	   1064	      0	  16682	   412a	drivers/net/ethernet/ibm/ibmveth.o
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver currently creates RX/TX queues during device probe, but
assigns IRQ's to them during device open. On reset, however,
IRQ's are assigned when resetting the queues. If there is a reset
while the device is closed and the device is later opened, the driver will
request IRQ's twice, causing the open to fail. This patch assigns
the IRQ's in the ibmvnic_init function after the queues are reset or
initialized, ensuring IRQ's are only requested once.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The update to ibmvnic_init to allow an EAGAIN return code broke
the calling of ibmvnic_init from ibmvnic_probe. The code now
will return from this point in the probe routine if anything
other than EAGAIN is returned. The check should be to see if rc
is non-zero and not equal to EAGAIN.

Without this fix, the vNIC driver can return 0 (success) from
its probe routine due to ibmvnic_init returning zero, but before
completing the probe process and registering with the netdev layer.

Fixes: 6a2fb0e9 (ibmvnic: driver initialization for kdump/kexec)
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The patch stores the return code of the REQUEST_MAP_RSP sub-CRQ command
in the private data structure, where it can be later checked during
device open or a reset.

In the case of a reset, the mapping request to the vNIC Server may fail,
especially in the case of a partition migration. The driver attempts to
handle this by re-allocating the buffer and re-sending the mapping request.

The original error handling implementation was removed. The separate
function handling the REQUEST_MAP response message was also removed,
since it is now simple enough to be handled in the ibmvnic_handle_crq
function.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reserved area should be eight bytes in length instead of four.
As a result, the return codes in the REQUEST_MAP_RSP descriptors
were not being properly handled.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the ibmvnic driver is not in the VNIC_OPEN state, return from
ibmvnic_resume callback. If we are not in the VNIC_OPEN state, interrupts
may not be initialized and directly calling the interrupt handler will
cause a crash.
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Reviewed-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

That way the driver doesn't have to rely on DMA_ERROR_CODE, which
is not a public API and going away.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NDavid S. Miller <davem@davemloft.net>

When booting into the kdump/kexec kernel, pHyp and vios
are not prepared for the initialization crq request and
a failover transport event is generated. This is not
handled correctly.

At this point in initialization the driver is still in
the 'probing' state and cannot handle a full reset of the
driver as is normally done for a failover transport event.

To correct this we catch driver resets while still in the
'probing' state and return EAGAIN. This results in the
driver tearing down the main crq and calling ibmvnic_init()
again.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes a bug where, in the case of a device reset,
the polling routine will never complete, causing napi_disable
to sleep indefinitely when attempting to close the device.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix a kernel panic resulting from data access of a NULL
pointer during device close. The pending_scrq routine is
meant to determine whether there is a valid sub-CRQ message
awaiting processing. When the device is closing, however,
there is a possibility that NULL messages can be processed
because pending_scrq will always return 1 even if there
no valid message in the queue.

It's not clear what this closing state check was originally
meant to accomplish, so just remove it.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixup a typo so that the entire SCRQ buffer is cleaned.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use netif_tx_disable to guarantee that TX queues are disabled
when __ibmvnic_close is called by the device reset routine.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RX buffer pools are disabled while awaiting a device
reset if firmware indicates that the resource is closed.

This patch fixes a bug where pools were not being
subsequently enabled after the device reset, causing
the device to become inoperable.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When handling a driver reset due to a failover of the backing
server on the vios, doing the netdev_notify_peers() can cause
network traffic to stall or halt. Remove the netdev notify call
for failover resets.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The IBM vNIC protocol provides support for the user to initiate
a failover from the client LPAR in case the current backing infrastructure
is deemed inadequate or in an error state.

Support for two H_VIOCTL sub-commands for vNIC devices are required
to implement this function. These commands are H_GET_SESSION_TOKEN
and H_SESSION_ERR_DETECTED.

"[H_GET_SESSION_TOKEN] is used to obtain a session token from a VNIC client
adapter.  This token is opaque to the caller and is intended to be used in
tandem with the SESSION_ERROR_DETECTED vioctl subfunction."

"[H_SESSION_ERR_DETECTED] is used to report that the currently active
backing device for a VNIC client adapter is behaving poorly, and that
the hypervisor should attempt to fail over to a different backing device,
if one is available."

To provide tools access to this functionality the vNIC driver creates a
sysfs file that, when written to, will send a request to pHyp to failover
to a different backing device.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Reviewed-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We are trying to get rid of DRIVER_ATTR(), and the ehea driver's
attribute can be trivially changed to use DRIVER_ATTR_RO().

Cc: Douglas Miller <dougmill@linux.vnet.ibm.com>
Cc: <netdev@vger.kernel.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The object references of mii_phy_ops structures are only stored
in the ops field of a mii_phy_def structure. This ops field is of type
const. So, mii_phy_ops structures having similar properties can be
declared as const.
Signed-off-by: NBhumika Goyal <bhumirks@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

emac_mdio_read_link() was not copying the requested phy settings
back into the emac driver's own phy api. This has caused a link
speed mismatch issue for the AR8035 as the emac driver kept
trying to connect with 10/100MBps on a 1GBit/s link.

This patch also unifies shared code between emac_setup_aneg()
and emac_mdio_setup_forced(). And furthermore it removes
a chunk of emac_mdio_init_phy(), that was copying the same
data into itself.
Signed-off-by: NChristian Lamparter <chunkeey@googlemail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes a problem where the AR8035 PHY can't be
detected on an Cisco Meraki MR24, if the ethernet cable is
not connected on boot.

Russell Senior provided steps to reproduce the issue:
|Disconnect ethernet cable, apply power, wait until device has booted,
|plug in ethernet, check for interfaces, no eth0 is listed.
|
|This appears to be a problem during probing of the AR8035 Phy chip.
|When ethernet has no link, the phy detection fails, and eth0 is not
|created. Plugging ethernet later has no effect, because there is no
|interface as far as the kernel is concerned. The relevant part of
|the boot log looks like this:
|this is the failing case:
|
|[    0.876611] /plb/opb/emac-rgmii@ef601500: input 0 in RGMII mode
|[    0.882532] /plb/opb/ethernet@ef600c00: reset timeout
|[    0.888546] /plb/opb/ethernet@ef600c00: can't find PHY!
|and the succeeding case:
|
|[    0.876672] /plb/opb/emac-rgmii@ef601500: input 0 in RGMII mode
|[    0.883952] eth0: EMAC-0 /plb/opb/ethernet@ef600c00, MAC 00:01:..
|[    0.890822] eth0: found Atheros 8035 Gigabit Ethernet PHY (0x01)

Based on the comment and the commit message of
commit 23fbb5a8 ("emac: Fix EMAC soft reset on 460EX/GT").
This is because the AR8035 PHY doesn't provide the TX Clock,
if the ethernet cable is not attached. This causes the reset
to timeout and the PHY detection code in emac_init_phy() is
unable to detect the AR8035 PHY. As a result, the emac driver
bails out early and the user left with no ethernet.

In order to stay compatible with existing configurations, the driver
tries the current reset approach at first. Only if the first attempt
timed out, it does perform one more retry with the clock temporarily
switched to the internal source for just the duration of the reset.

LEDE-Bug: #687 <https://bugs.lede-project.org/index.php?do=details&task_id=687>

Cc: Chris Blake <chrisrblake93@gmail.com>
Reported-by: NRussell Senior <russell@personaltelco.net>
Fixes: 23fbb5a8 ("emac: Fix EMAC soft reset on 460EX/GT")
Signed-off-by: NChristian Lamparter <chunkeey@googlemail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Changing the mtu is currently not supported in the ibmvnic driver.

Implement .ndo_change_mtu in the driver so that attempting to use ifconfig
to change the mtu will fail and present the user with an error message.
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The original author left the project and so far has not
responded to emails sent to the listed address.
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the ibmvnic driver is resetting, we can just reset the sub crqs
instead of releasing all of their resources and re-allocting them.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When resetting the ibmvnic driver there is not a need to release
and re-allocate the resources for the tx and rx pools. These
resources can just be reset to avoid the re-allocations.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a driver reset operation occurs there is not a need to release
the CRQ resources and re-allocate them. Instead a reset of the CRQ
will suffice.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We do not want to process any receive frames if the ibmvnic_poll
routine is invoked while a reset is in process. Also, before
replenishing the rx pools in the ibmvnic_poll, we want to
make sure the adapter is not in the process of closing.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If H_CLOSED is returned, halt RX buffer replenishment activity
until firmware sends a notification that the driver can reset.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch disables transmissions and reports carrier off if xmit
function returns that the hardware TX queue is closed. The driver can
then await a signal from firmware to determine the correct reset method.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Handle non-fatal error conditions. The process to do this when
resetting the driver is to just do __ibmvnic_close followed by
__ibmvnic_open.
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A race condition occurs when closing the driver. Free'ing of skb's
can race between the close routine and ibmvnic_tx_interrupt. To fix
this we move the claenup of tx pools during close to after the
sub-CRQ interrupts are disabled.
Signed-off-by: NThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Send gratuitous arp after any reset.
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Handle case where phyp sends a failover after failing to send the
init crq.
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Track the state of ibmvnic napis. The driver can get into states where it
can be reset when napis are already disabled and attempting to disable them
again will cause the driver to hang.
Signed-off-by: NJohn Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Current largesend and checksum offload feature in ibmveth driver,
 - Source VM sends the TCP packets with ip_summed field set as
   CHECKSUM_PARTIAL and TCP pseudo header checksum is placed in
   checksum field
 - CHECKSUM_PARTIAL flag in SKB will enable ibmveth driver to mark
   "no checksum" and "checksum good" bits in transmit buffer descriptor
   before the packet is delivered to pseries PowerVM Hypervisor
 - If ibmveth has largesend capability enabled, transmit buffer descriptors
   are market accordingly before packet is delivered to Hypervisor
   (along with mss value for packets with length > MSS)
 - Destination VM's ibmveth driver receives the packet with "checksum good"
   bit set and so, SKB's ip_summed field is set with CHECKSUM_UNNECESSARY
 - If "largesend" bit was on, mss value is copied from receive descriptor
   into SKB's gso_size and other flags are appropriately set for
   packets > MSS size
 - The packet is now successfully delivered up the stack in destination VM

The offloads described above works fine for TCP communication among VMs in
the same pseries server ( VM A <=> PowerVM Hypervisor <=> VM B )

We are now enabling support for OVS in pseries PowerVM environment. One of
our requirements is to have ibmveth driver configured in "Trunk" mode, when
they are used with OVS. This is because, PowerVM Hypervisor will no more
bridge the packets between VMs, instead the packets are delivered to
IO Server which hosts OVS to bridge them between VMs or to external
networks (flow shown below),
  VM A <=> PowerVM Hypervisor <=> IO Server(OVS) <=> PowerVM Hypervisor
                                                                   <=> VM B
In "IO server" the packet is received by inbound Trunk ibmveth and then
delivered to OVS, which is then bridged to outbound Trunk ibmveth (shown
below),
        Inbound Trunk ibmveth <=> OVS <=> Outbound Trunk ibmveth

In this model, we hit the following issues which impacted the VM
communication performance,

 - Issue 1: ibmveth doesn't support largesend and checksum offload features
   when configured as "Trunk". Driver has explicit checks to prevent
   enabling these offloads.

 - Issue 2: SYN packet drops seen at destination VM. When the packet
   originates, it has CHECKSUM_PARTIAL flag set and as it gets delivered to
   IO server's inbound Trunk ibmveth, on validating "checksum good" bits
   in ibmveth receive routine, SKB's ip_summed field is set with
   CHECKSUM_UNNECESSARY flag. This packet is then bridged by OVS (or Linux
   Bridge) and delivered to outbound Trunk ibmveth. At this point the
   outbound ibmveth transmit routine will not set "no checksum" and
   "checksum good" bits in transmit buffer descriptor, as it does so only
   when the ip_summed field is CHECKSUM_PARTIAL. When this packet gets
   delivered to destination VM, TCP layer receives the packet with checksum
   value of 0 and with no checksum related flags in ip_summed field. This
   leads to packet drops. So, TCP connections never goes through fine.

 - Issue 3: First packet of a TCP connection will be dropped, if there is
   no OVS flow cached in datapath. OVS while trying to identify the flow,
   computes the checksum. The computed checksum will be invalid at the
   receiving end, as ibmveth transmit routine zeroes out the pseudo
   checksum value in the packet. This leads to packet drop.

 - Issue 4: ibmveth driver doesn't have support for SKB's with frag_list.
   When Physical NIC has GRO enabled and when OVS bridges these packets,
   OVS vport send code will end up calling dev_queue_xmit, which in turn
   calls validate_xmit_skb.
   In validate_xmit_skb routine, the larger packets will get segmented into
   MSS sized segments, if SKB has a frag_list and if the driver to which
   they are delivered to doesn't support NETIF_F_FRAGLIST feature.

This patch addresses the above four issues, thereby enabling end to end
largesend and checksum offload support for better performance.

 - Fix for Issue 1 : Remove checks which prevent enabling TCP largesend and
   checksum offloads.
 - Fix for Issue 2 : When ibmveth receives a packet with "checksum good"
   bit set and if its configured in Trunk mode, set appropriate SKB fields
   using skb_partial_csum_set (ip_summed field is set with
   CHECKSUM_PARTIAL)
 - Fix for Issue 3: Recompute the pseudo header checksum before sending the
   SKB up the stack.
 - Fix for Issue 4: Linearize the SKBs with frag_list. Though we end up
   allocating buffers and copying data, this fix gives
   upto 4X throughput increase.

Note: All these fixes need to be dropped together as fixing just one of
them will lead to other issues immediately (especially for Issues 1,2 & 3).
Signed-off-by: NSivakumar Krishnasamy <ksiva@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add the missing unlock before return from function __ibmvnic_reset()
in the error handling case.

Fixes: ed651a10 ("ibmvnic: Updated reset handling")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Restart of the subqueue should occur outside of the loop processing
any tx buffers instead of doing this in the middle of the loop.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>