Allows an extra channel to override the standard receive_skb handler
and also for extra non generic operations to be performed on remove.

Also set default rx strategy so only skbs can be delivered to the
PTP receive function.
Signed-off-by: NStuart Hodgson <smhodgson@solarflare.com>
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

The PTP channel will have its own RX queue even though it's not
a regular traffic channel.

Original work by Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: NStuart Hodgson <smhodgson@solarflare.com>
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Following commit 8f4cccbb ('net: Set device operstate at registration
time') it is now correct and preferable to set the carrier off before
registering a device.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

We also stop clearing *efx in efx_init_struct().  This is safe because
alloc_etherdev_mq() already clears it for us.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

RX DMA is limited by the length specified in each descriptor and not
by the MAC.  Over-length frames may get into the RX FIFO regardless of
the MAC settings, due to a hardware bug, but they will be truncated by
the packet DMA engine and reported as such in the completion event.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

We try to defer resets while the device is not READY, but we're not
doing this quite correctly.  In particular, changes to efx_nic::state
are documented as serialised by the RTNL lock, but they aren't.

1. We check whether a reset was requested during probe (suggesting
broken hardware) before we allow requested resets to be scheduled.
This leaves a window where a requested reset would be deferred
indefinitely.

2. Although we cancel the reset work item during device removal,
there are still later operations that can cause it to be scheduled
again.  We need to check the state before scheduling it.

3. Since the state can change between scheduling and running of
the work item, we still need to check it there, and we need to
do so *after* acquiring the RTNL lock which serialises state
changes.

4. We must cancel the reset work item during device removal, if the
state could ever have been READY.  This wasn't done in some of the
failure paths from efx_pci_probe().  Move the cancellation to
efx_pci_remove_main().
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

The current informational message doesn't properly explain what
happens, and could also appear if we defer a reset during
suspend/resume.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

efx_change_mtu() and efx_realloc_channels() each stop and start much
of the NIC, even if it has been disabled.  Since efx_start_all() is a
no-op when the NIC is disabled, this is probably harmless in the case
of efx_change_mtu(), but efx_realloc_channels() also reenables
interrupts which could be a bad thing to do.

Change efx_start_all() and efx_start_interrupts() to assert that the
NIC is not disabled, but make efx_stop_interrupts() do nothing if the
NIC is disabled (since it is already stopped), consistent with
efx_stop_all().

Update comments for efx_start_all() and efx_stop_all() to describe
their purpose and preconditions more accurately.

Add a common function to check and log if the NIC is disabled, and use
it in efx_net_open(), efx_change_mtu() and efx_realloc_channels().
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Interrupt state should be consistently guarded by the RTNL lock once
the net device is registered.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Currently we ignore and clear the disabled state.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

I don't think these PM functions can race with userland net device
operations, but it's much easier to reason about locking if state is
consistently guarded by the same lock.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

STATE_INIT and STATE_FINI are equivalent and represent incompletely
initialised states; combine them as STATE_UNINIT.

Rename STATE_RUNNING to STATE_READY, to avoid confusion with
netif_running() and IFF_RUNNING.

The comments do not quite match current usage, but this will be
corrected in subsequent fixes.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

We only use tso_state::full_packet_space to calculate the IPv4 tot_len
or IPv6 payload_len, not to set tso_state::packet_space.  Replace it
with an ip_base_len field holding the value of tot_len or payload_len
before including the TCP payload, which is much more useful when
constructing the new headers.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

TSO header buffers contain a control structure immediately followed by
the packet headers, and are kept on a free list when not in use.  This
complicates buffer management and tends to result in cache read misses
when we recycle such buffers (particularly if DMA-coherent memory
requires caches to be disabled).

Replace the free list with a simple mapping by descriptor index.  We
know that there is always a payload descriptor between any two
descriptors with TSO header buffers, so we can allocate only one
such buffer for each two descriptors.

While we're at it, use a standard error code for allocation failure,
not -1.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

We now have a definite upper bound on the number of descriptors per
skb; use that to stop the queue when the next packet might not fit.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Add a flags field to struct efx_tx_buffer, replacing the
continuation and map_single booleans.

Since a single descriptor cannot be both a TSO header and the last
descriptor for an skb, unionise efx_tx_buffer::{skb,tsoh} and add
flags for validity of these fields.

Clear all flags in free buffers (whereas previously the continuation
flag would be set).
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

ETHTOOL_GRXCLSRULE returns filters for a TCP/IPv4 or UDP/IPv4 4-tuple
with source and destination swapped.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Currently an skb requiring TSO may not fit within a minimum-size TX
queue.  The TX queue selected for the skb may stall and trigger the TX
watchdog repeatedly (since the problem skb will be retried after the
TX reset).  This issue is designated as CVE-2012-3412.

Set the maximum number of TSO segments for our devices to 100.  This
should make no difference to behaviour unless the actual MSS is less
than about 700.  Increase the minimum TX queue size accordingly to
allow for 2 worst-case skbs, so that there will definitely be space
to add an skb after we wake a queue.

To avoid invalidating existing configurations, change
efx_ethtool_set_ringparam() to fix up values that are too small rather
than returning -EINVAL.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Dynamically allocated sysfs attributes must be initialized using
sysfs_attr_init(), otherwise lockdep complains:
BUG: key <address> not in .data!
Signed-off-by: NMichal Schmidt <mschmidt@redhat.com>
Acked-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Some interface statistics are computed in such a way that they can
sometimes decrease (and even underflow).  Since the computed value
will never be greater than the true value, we fix this by only storing
the computed value when it increases.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Currently VF queues and drivers may remain active during this test.
This could cause memory corruption or spurious test failures.
Therefore we reset the port/function before running these tests on
Siena.

On Falcon this doesn't work: we have to do some additional
initialisation before some blocks will work again.  So refactor the
reset/register-test sequence into an efx_nic_type method so
efx_selftest() doesn't have to consider such quirks.

In the process, fix another minor bug: Siena does not have an
'invisible' reset and the self-test currently fails to push the PHY
configuration after resetting.  Passing RESET_TYPE_ALL to
efx_reset_{down,up}() fixes this.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Fix CID 113952 in Coverity report on Linux.

This is the one instance where we don't, and shouldn't, check the
return code from efx_mcdi_rpc().  It wasn't immediately obvious to me
why we didn't, so I think an explanation is in order.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Fix CID 102619 in the Coverity report on Linux.

efx_end_loopback() iterates over an array of skb pointers of which
some may be null (if efx_begin_loopback() failed).  It should not use
dev_kfree_skb_irq(), which requires non-null pointers.  In practice
this is safe because it does not run in interrupt context and
therefore always ends up calling dev_kfree_skb(), which does allow
null pointers.  But we should make that explicit.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Fix CID 113703 in the Coverity report on Linux.

ethtool stats names are limited to 32 bytes including a null
terminator.  Use strlcpy() to ensure that we will always include the
null terminator even if a source string becomes longer than this.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

There is nothing in the VLAN driver or core VLAN support that
invalidates the TCP and IP header offsets.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

tso_state::packet_space is always set in tso_start_packet(); the
value set in tso_start() is not used, and is also incorrect.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

With some gcc versions & optimisations, the compiler will warn that
'depth' in efx_filter_insert_filter() may be used without being
initialised, although this is not the case.

This is related to inlining of efx_filter_search(), which only has
one caller since commit 8db182f4
('sfc: Remove now-unused filter function').

Shut the compiler up by initialising it to 0.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Convert doxygen (or similar) formatted comments to kernel-doc or
unformatted comment.  Delete a few that are content-free.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Acked-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix incorrect start markers, wrapped summary lines, missing section
breaks, incorrect separators, and some name mismatches.  Delete
a few that are content-free.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Acked-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the new bool function ether_addr_equal to add
some clarity and reduce the likelihood for misuse
of compare_ether_addr for sorting.

Done via cocci script:

$ cat compare_ether_addr.cocci
@@
expression a,b;
@@
-	!compare_ether_addr(a, b)
+	ether_addr_equal(a, b)

@@
expression a,b;
@@
-	compare_ether_addr(a, b)
+	!ether_addr_equal(a, b)

@@
expression a,b;
@@
-	!ether_addr_equal(a, b) == 0
+	ether_addr_equal(a, b)

@@
expression a,b;
@@
-	!ether_addr_equal(a, b) != 0
+	!ether_addr_equal(a, b)

@@
expression a,b;
@@
-	ether_addr_equal(a, b) == 0
+	!ether_addr_equal(a, b)

@@
expression a,b;
@@
-	ether_addr_equal(a, b) != 0
+	ether_addr_equal(a, b)

@@
expression a,b;
@@
-	!!ether_addr_equal(a, b)
+	ether_addr_equal(a, b)
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Currently allows for SFP+ eeprom to be returned using the ethtool API.
This can be extended in future to handle different eeprom formats
and sizes
Signed-off-by: NStuart Hodgson <smhodgson@solarflare.com>
[bwh: Drop redundant validation, comment, whitespace]
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Previously we refilled with much larger batches, which caused large latency
spikes.  We now have many more much much smaller spikes!
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

There was no runtime control of the fast_fill_limit in any case, so purged
that field.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

We need to clear the private data pointer in the PCI device.
Also reorder cleanup in efx_pci_remove() for symmetry.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

efx_nic_fatal_interrupt() disables DMA before scheduling a reset.
After this, we need not and *cannot* flush queues.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>