mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER

commit 23baf831a32c ("mm, treewide: redefine MAX_ORDER sanely") has
changed the definition of MAX_ORDER to be inclusive. This has caused
issues with code that was not yet upstream and depended on the previous
definition.

To draw attention to the altered meaning of the define, rename MAX_ORDER
to MAX_PAGE_ORDER.

Link: https://lkml.kernel.org/r/20231228144704.14033-2-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm, treewide: redefine MAX_ORDER sanely

MAX_ORDER currently defined as number of orders page allocator supports:
user can ask buddy allocator for page order between 0 and MAX_ORDER-1.

This definition is counter-intuitive and lead to number of bugs all over
the kernel.

Change the definition of MAX_ORDER to be inclusive: the range of orders
user can ask from buddy allocator is 0..MAX_ORDER now.

[kirill@shutemov.name: fix min() warning]
Link: https://lkml.kernel.org/r/20230315153800.32wib3n5rickolvh@box
[akpm@linux-foundation.org: fix another min_t warning]
[kirill@shutemov.name: fixups per Zi Yan]
Link: https://lkml.kernel.org/r/20230316232144.b7ic4cif4kjiabws@box.shutemov.name
[akpm@linux-foundation.org: fix underlining in docs]
Link: https://lore.kernel.org/oe-kbuild-all/202303191025.VRCTk6mP-lkp@intel.com/
Link: https://lkml.kernel.org/r/20230315113133.11326-11-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

ibmvnic: Add hotpluggable CPU callbacks to reassign affinity hints

When CPU's are added and removed, ibmvnic devices will reassign
hint values. Introduce a new cpu hotplug state CPUHP_IBMVNIC_DEAD
to signal to ibmvnic devices that the CPU has been removed and it
is time to reset affinity hint assignments. On the other hand,
when CPU's are being added, add a state instance to
CPUHP_AP_ONLINE_DYN which will trigger a reassignment of affinity
hints once the new CPU's are online. This implementation is based
on the virtio_net driver.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Nick Child <nnac123@linux.ibm.com>
Reviewed-by: Rick Lindsley <ricklind@linux.ibm.com>
Reviewed-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Assign IRQ affinity hints to device queues

Assign affinity hints to ibmvnic device queue interrupts.
Affinity hints are assigned and removed during sub-crq init and
teardown, respectively. This update should improve latency if
utilized as interrupt lines and processing are more equally
distributed among CPU's. This implementation is based on the
virtio_net driver.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Nick Child <nnac123@linux.ibm.com>
Reviewed-by: Rick Lindsley <ricklind@linux.ibm.com>
Reviewed-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Allow multiple ltbs in txpool ltb_set

Allow multiple LTBs in the txpool's ltb_set. i.e rather than using
a single large LTB, use several smaller LTBs.

The first n-1 LTBs will all be of the same size. The size of the last
LTB in the set depends on the number of buffers and buffer (mtu) size.
This strategy hopefully allows more reuse of the initial LTBs and also
reduces the chances of an allocation failure (of the large LTB) when
system is low in memory.

Suggested-by: Brian King <brking@linux.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ibmvnic: Allow multiple ltbs in rxpool ltb_set

Allow multiple LTBs in the rxpool's ltb_set. The first n-1 LTBs will all
be of the same size. The size of the last LTB in the set depends on the
number of buffers and buffer (mtu) size.

Having a set of LTBs per pool provides a couple of benefits.

First, with the current value of IBMVNIC_MAX_LTB_SIZE of 16MB, with an
MTU of 9000, we need a LTB (DMA buffer) of that size but the allocation
can fail in low memory conditions. With a set of LTBs per pool, we can
use several smaller (8MB) LTBs and hopefully have fewer allocation
failures. (See also comments in ibmvnic.h on the trade-off with smaller
LTBs)

Second since the kernel limits the size of the DMA buffer to 16MB (based
on MAX_ORDER), with a single DMA buffer per pool, the pool is also limited
to 16MB. This in turn limits the number of buffers per pool to 1763 when
MTU is 9000. With a set of LTBs per pool, we can have upto the max of 4096
buffers per pool even when MTU is 9000.

Suggested-by: Brian King <brking@linux.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ibmvnic: convert rxpool ltb to a set of ltbs

Define and use interfaces that treat the long term buffer (LTB) of an
rxpool as a set of LTBs rather than a single LTB. The set only has one
LTB for now.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Revert "ibmvnic: Add ethtool private flag for driver-defined queue limits"

This reverts commit 723ad916134784b317b72f3f6cf0f7ba774e5dae

When client requests channel or ring size larger than what the server
can support the server will cap the request to the supported max. So,
the client would not be able to successfully request resources that
exceed the server limit.

Fixes: 723ad9161347 ("ibmvnic: Add ethtool private flag for driver-defined queue limits")
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Link: https://lore.kernel.org/r/20220427235146.23189-1-drt@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ibmvnic: fix race between xmit and reset

There is a race between reset and the transmit paths that can lead to
ibmvnic_xmit() accessing an scrq after it has been freed in the reset
path. It can result in a crash like:

Kernel attempted to read user page (0) - exploit attempt? (uid: 0)
BUG: Kernel NULL pointer dereference on read at 0x00000000
Faulting instruction address: 0xc0080000016189f8
Oops: Kernel access of bad area, sig: 11 [#1]
...
NIP [c0080000016189f8] ibmvnic_xmit+0x60/0xb60 [ibmvnic]
LR [c000000000c0046c] dev_hard_start_xmit+0x11c/0x280
Call Trace:
[c008000001618f08] ibmvnic_xmit+0x570/0xb60 [ibmvnic] (unreliable)
[c000000000c0046c] dev_hard_start_xmit+0x11c/0x280
[c000000000c9cfcc] sch_direct_xmit+0xec/0x330
[c000000000bfe640] __dev_xmit_skb+0x3a0/0x9d0
[c000000000c00ad4] __dev_queue_xmit+0x394/0x730
[c008000002db813c] __bond_start_xmit+0x254/0x450 [bonding]
[c008000002db8378] bond_start_xmit+0x40/0xc0 [bonding]
[c000000000c0046c] dev_hard_start_xmit+0x11c/0x280
[c000000000c00ca4] __dev_queue_xmit+0x564/0x730
[c000000000cf97e0] neigh_hh_output+0xd0/0x180
[c000000000cfa69c] ip_finish_output2+0x31c/0x5c0
[c000000000cfd244] __ip_queue_xmit+0x194/0x4f0
[c000000000d2a3c4] __tcp_transmit_skb+0x434/0x9b0
[c000000000d2d1e0] __tcp_retransmit_skb+0x1d0/0x6a0
[c000000000d2d984] tcp_retransmit_skb+0x34/0x130
[c000000000d310e8] tcp_retransmit_timer+0x388/0x6d0
[c000000000d315ec] tcp_write_timer_handler+0x1bc/0x330
[c000000000d317bc] tcp_write_timer+0x5c/0x200
[c000000000243270] call_timer_fn+0x50/0x1c0
[c000000000243704] __run_timers.part.0+0x324/0x460
[c000000000243894] run_timer_softirq+0x54/0xa0
[c000000000ea713c] __do_softirq+0x15c/0x3e0
[c000000000166258] __irq_exit_rcu+0x158/0x190
[c000000000166420] irq_exit+0x20/0x40
[c00000000002853c] timer_interrupt+0x14c/0x2b0
[c000000000009a00] decrementer_common_virt+0x210/0x220
--- interrupt: 900 at plpar_hcall_norets_notrace+0x18/0x2c

The immediate cause of the crash is the access of tx_scrq in the following
snippet during a reset, where the tx_scrq can be either NULL or an address
that will soon be invalid:

ibmvnic_xmit()
{
...
tx_scrq = adapter->tx_scrq[queue_num];
txq = netdev_get_tx_queue(netdev, queue_num);
ind_bufp = &tx_scrq->ind_buf;

if (test_bit(0, &adapter->resetting)) {
...
}

But beyond that, the call to ibmvnic_xmit() itself is not safe during a
reset and the reset path attempts to avoid this by stopping the queue in
ibmvnic_cleanup(). However just after the queue was stopped, an in-flight
ibmvnic_complete_tx() could have restarted the queue even as the reset is
progressing.

Since the queue was restarted we could get a call to ibmvnic_xmit() which
can then access the bad tx_scrq (or other fields).

We cannot however simply have ibmvnic_complete_tx() check the ->resetting
bit and skip starting the queue. This can race at the "back-end" of a good
reset which just restarted the queue but has not cleared the ->resetting
bit yet. If we skip restarting the queue due to ->resetting being true,
the queue would remain stopped indefinitely potentially leading to transmit
timeouts.

IOW ->resetting is too broad for this purpose. Instead use a new flag
that indicates whether or not the queues are active. Only the open/
reset paths control when the queues are active. ibmvnic_complete_tx()
and others wake up the queue only if the queue is marked active.

So we will have:
A. reset/open thread in ibmvnic_cleanup() and __ibmvnic_open()

->resetting = true
->tx_queues_active = false
disable tx queues
...
->tx_queues_active = true
start tx queues

B. Tx interrupt in ibmvnic_complete_tx():

if (->tx_queues_active)
netif_wake_subqueue();

To ensure that ->tx_queues_active and state of the queues are consistent,
we need a lock which:

- must also be taken in the interrupt path (ibmvnic_complete_tx())
- shared across the multiple queues in the adapter (so they don't
become serialized)

Use rcu_read_lock() and have the reset thread synchronize_rcu() after
updating the ->tx_queues_active state.

While here, consolidate a few boolean fields in ibmvnic_adapter for
better alignment.

Based on discussions with Brian King and Dany Madden.

Fixes: 7ed5b31f4a66 ("net/ibmvnic: prevent more than one thread from running in reset")
Reported-by: Vaishnavi Bhat <vaish123@in.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Allow queueing resets during probe

We currently don't allow queuing resets when adapter is in VNIC_PROBING
state - instead we throw away the reset and return EBUSY. The reasoning
is probably that during ibmvnic_probe() the ibmvnic_adapter itself is
being initialized so performing a reset during this time can lead us to
accessing fields in the ibmvnic_adapter that are not fully initialized.
A review of the code shows that all the adapter state neede to process a
reset is initialized before registering the CRQ so that should no longer
be a concern.

Further the expectation is that if we do get a reset (transport event)
during probe, the do..while() loop in ibmvnic_probe() will handle this
by reinitializing the CRQ.

While that is true to some extent, it is possible that the reset might
occur _after_ the CRQ is registered and CRQ_INIT message was exchanged
but _before_ the adapter state is set to VNIC_PROBED. As mentioned above,
such a reset will be thrown away. While the client assumes that the
adapter is functional, the vnic server will wait for the client to reinit
the adapter. This disconnect between the two leaves the adapter down
needing manual intervention.

Because ibmvnic_probe() has other work to do after initializing the CRQ
(such as registering the netdev at a minimum) and because the reset event
can occur at any instant after the CRQ is initialized, there will always
be a window between initializing the CRQ and considering the adapter
ready for resets (ie state == PROBED).

So rather than discarding resets during this window, allow queueing them
- but only process them after the adapter is fully initialized.

To do this, introduce a new completion state ->probe_done and have the
reset worker thread wait on this before processing resets.

This change brings up two new situations in or just after ibmvnic_probe().
First after one or more resets were queued, we encounter an error and
decide to retry the initialization. At that point the queued resets are
no longer relevant since we could be talking to a new vnic server. So we
must purge/flush the queued resets before restarting the initialization.
As a side note, since we are still in the probing stage and we have not
registered the netdev, it will not be CHANGE_PARAM reset.

Second this change opens up a potential race between the worker thread
in __ibmvnic_reset(), the tasklet and the ibmvnic_open() due to the
following sequence of events:

1. Register CRQ
2. Get transport event before CRQ_INIT completes.
3. Tasklet schedules reset:
a) add rwi to list
b) schedule_work() to start worker thread which runs
and waits for ->probe_done.
4. ibmvnic_probe() decides to retry, purges rwi_list
5. Re-register crq and this time rest of probe succeeds - register
netdev and complete(->probe_done).
6. Worker thread resumes in __ibmvnic_reset() from 3b.
7. Worker thread sets ->resetting bit
8. ibmvnic_open() comes in, notices ->resetting bit, sets state
to IBMVNIC_OPEN and returns early expecting worker thread to
finish the open.
9. Worker thread finds rwi_list empty and returns without
opening the interface.

If this happens, the ->ndo_open() call is effectively lost and the
interface remains down. To address this, ensure that ->rwi_list is
not empty before setting the ->resetting bit. See also comments in
__ibmvnic_reset().

Fixes: 6a2fb0e99f9c ("ibmvnic: driver initialization for kdump/kexec")
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: remove unused ->wait_capability

With previous bug fix, ->wait_capability flag is no longer needed and can
be removed.

Fixes: 249168ad07cd ("ibmvnic: Make CRQ interrupt tasklet wait for all capabilities crqs")
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Reviewed-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: remove unused defines

IBMVNIC_STATS_TIMEOUT and IBMVNIC_INIT_FAILED are not used in the driver.
Remove them.

Suggested-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Reuse tx pools when possible

Rather than releasing the tx pools on every close and reallocating
them on open, reuse the tx pools unless the pool parameters (number
of pools, size of each pool or size of each buffer in a pool) have
changed.

If the pool parameters changed, then release the old pools (if
any) and allocate new ones.

Specifically release tx pools, if:
- adapter is removed,
- pool parameters change during reset,
- we encounter an error when opening the adapter in response
to a user request (in ibmvnic_open()).

and don't release them:
- in __ibmvnic_close() or
- on errors in __ibmvnic_open()

in the hope that we can reuse them during this or next reset.

With these changes reset_tx_pools() can be dropped because its
optimization is now included in init_tx_pools() itself.

cleanup_tx_pools() releases all the skbs associated with the pool and
is called from ibmvnic_cleanup(), which is called on every reset. Since
we want to reuse skbs across resets, move cleanup_tx_pools() out of
ibmvnic_cleanup() and call it only when user closes the adapter.

Add two new adapter fields, ->prev_mtu, ->prev_tx_pool_size to track the
previous values and use them to decide whether to reuse or realloc the
pools.

Reviewed-by: Rick Lindsley <ricklind@linux.vnet.ibm.com>
Reviewed-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Reuse rx pools when possible

Rather than releasing the rx pools on and reallocating them on every
reset, reuse the rx pools unless the pool parameters (number of pools,
size of each pool or size of each buffer in a pool) have changed.

If the pool parameters changed, then release the old pools (if any)
and allocate new ones.

Specifically release rx pools, if:
- adapter is removed,
- pool parameters change during reset,
- we encounter an error when opening the adapter in response
to a user request (in ibmvnic_open()).

and don't release them:
- in __ibmvnic_close() or
- on errors in __ibmvnic_open()

in the hope that we can reuse them on the next reset.

With these, reset_rx_pools() can be dropped because its optimzation is
now included in init_rx_pools() itself.

cleanup_rx_pools() releases all the skbs associated with the pool and
is called from ibmvnic_cleanup(), which is called on every reset. Since
we want to reuse skbs across resets, move cleanup_rx_pools() out of
ibmvnic_cleanup() and call it only when user closes the adapter.

Add two new adapter fields, ->prev_rx_buf_sz, ->prev_rx_pool_size to
keep track of the previous values and use them to decide whether to
reuse or realloc the pools.

Reviewed-by: Rick Lindsley <ricklind@linux.vnet.ibm.com>
Reviewed-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Use bitmap for LTB map_ids

In a follow-on patch, we will reuse long term buffers when possible.
When doing so we have to be careful to properly assign map ids. We
can no longer assign them sequentially because a lower map id may be
available and we could wrap at 255 and collide with an in-use map id.

Instead, use a bitmap to track active map ids and to find a free map id.
Don't need to take locks here since the map_id only changes during reset
and at that time only the reset worker thread should be using the adapter.

Noticed this when analyzing an error Dany Madden ran into with the
patch set.

Reported-by: Dany Madden <drt@linux.ibm.com>
Reviewed-by: Rick Lindsley <ricklind@linux.vnet.ibm.com>
Reviewed-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Use/rename local vars in init_rx_pools

To make the code more readable, use/rename some local variables.
Basically we have a set of pools, num_pools. Each pool has a set of
buffers, pool_size and each buffer is of size buff_size.

pool_size is a bit ambiguous (whether size in bytes or buffers). Add
a comment in the header file to make it explicit.

Reviewed-by: Rick Lindsley <ricklind@linux.vnet.ibm.com>
Reviewed-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Allow device probe if the device is not ready at boot

Allow the device to be initialized at a later time if
it is not available at boot. The device will be allowed to probe but
will be given a "down" state. After completing device probe and
registering the net device, the driver will await an interrupt signal
from its partner device, indicating that it is ready for boot. The
driver will schedule a work event to perform the necessary procedure
and begin operation.

Co-developed-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: Cristobal Forno <cforno12@linux.ibm.com>
Acked-by: Lijun Pan <lijunp213@gmail.com>
Reviewed-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: clean up the remaining debugfs data structures

Commit e704f0434ea6 ("ibmvnic: Remove debugfs support") did not
clean up everything. Remove the remaining code.

Signed-off-by: Lijun Pan <lijunp213@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: re-solve some conflicts after net -> net-next merge

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ibmvnic: serialize access to work queue on remove

The work queue is used to queue reset requests like CHANGE-PARAM or
FAILOVER resets for the worker thread. When the adapter is being removed
the adapter state is set to VNIC_REMOVING and the work queue is flushed
so no new work is added. However the check for adapter being removed is
racy in that the adapter can go into REMOVING state just after we check
and we might end up adding work just as it is being flushed (or after).

The ->rwi_lock is already being used to serialize queue/dequeue work.
Extend its usage ensure there is no race when scheduling/flushing work.

Fixes: 6954a9e4192b ("ibmvnic: Flush existing work items before device removal")
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Cc:Uwe Kleine-König <uwe@kleine-koenig.org>
Cc:Saeed Mahameed <saeed@kernel.org>
Reviewed-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: change IBMVNIC_MAX_IND_DESCS to 16

The supported indirect subcrq entries on Power8 is 16. Power9
supports 128. Redefined this value to 16 to minimize the driver from
having to reset when migrating between Power9 and Power8. In our rx/tx
performance testing, we found no performance difference between 16 and
128 at this time.

Fixes: f019fb6392e5 ("ibmvnic: Introduce indirect subordinate Command Response Queue buffer")
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: remove unused spinlock_t stats_lock definition

stats_lock is no longer used. So remove it.

Signed-off-by: Lijun Pan <lijunp213@gmail.com>
Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: add comments for spinlock_t definitions

There are several spinlock_t definitions without comments.
Add them.

Signed-off-by: Lijun Pan <lijunp213@gmail.com>
Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: no reset timeout for 5 seconds after reset

Reset timeout is going off right after adapter reset. This patch ensures
that timeout is scheduled if it has been 5 seconds since the last reset.
5 seconds is the default watchdog timeout.

Fixes: ed651a10875f1 ("ibmvnic: Updated reset handling")
Signed-off-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ibmvnic: track pending login

If after ibmvnic sends a LOGIN it gets a FAILOVER, it is possible that
the worker thread will start reset process and free the login response
buffer before it gets a (now stale) LOGIN_RSP. The ibmvnic tasklet will
then try to access the login response buffer and crash.

Have ibmvnic track pending logins and discard any stale login responses.

Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol")
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ibmvnic: enhance resetting status check during module exit

Based on the discussion with Sukadev Bhattiprolu and Dany Madden,
we believe that checking adapter->resetting bit is preferred
since RESETTING state flag is not as strict as resetting bit.
RESETTING state flag is removed since it is verbose now.

Fixes: 7d7195a026ba ("ibmvnic: Do not process device remove during device reset")
Signed-off-by: Lijun Pan <ljp@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ibmvnic: Ensure that device queue memory is cache-line aligned

PCI bus slowdowns were observed on IBM VNIC devices as a result
of partial cache line writes and non-cache aligned full cache line writes.
Ensure that packet data buffers are cache-line aligned to avoid these
slowdowns.

Signed-off-by: Dwip N. Banerjee <dnbanerg@us.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ibmvnic: Clean up TX code and TX buffer data structure

Remove unused and superfluous code and members in
existing TX implementation and data structures.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ibmvnic: Introduce indirect subordinate Command Response Queue buffer

This patch introduces the infrastructure to send batched subordinate
Command Response Queue descriptors, which are used by the ibmvnic
driver to send TX frame and RX buffer descriptors.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Acked-by: Lijun Pan <ljp@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ibmvnic: set up 200GBPS speed

Set up the speed according to crq->query_phys_parms.rsp.speed.
Fix IBMVNIC_10GBPS typo.

Fixes: f8d6ae0d27ec ("ibmvnic: Report actual backing device speed and duplex values")
Signed-off-by: Lijun Pan <ljp@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix use-after-free of VNIC login response buffer

The login response buffer is freed after it is received
and parsed, but other functions in the driver still attempt
to read it, such as when the device is opened, causing the
Oops below. Store relevant information in the driver's
private data structures and use those instead.

BUG: Kernel NULL pointer dereference on read at 0x00000010
Faulting instruction address: 0xc00800000050a900
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
Modules linked in: pseries_rng rng_core vmx_crypto gf128mul binfmt_misc ip_tables x_tables ibmvnic ibmveth crc32c_vpmsum autofs4
CPU: 7 PID: 759 Comm: NetworkManager Not tainted 5.9.0-rc1-00124-gd0a84e1f38d9 #14
NIP: c00800000050a900 LR: c00800000050a8f0 CTR: 00000000005b1904
REGS: c0000001ed746d20 TRAP: 0300 Not tainted (5.9.0-rc1-00124-gd0a84e1f38d9)
MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24428484 XER: 00000001
CFAR: c0000000000101b0 DAR: 0000000000000010 DSISR: 40000000 IRQMASK: 0
GPR00: c00800000050a8f0 c0000001ed746fb0 c008000000518e00 0000000000000000
GPR04: 00000000000000c0 0000000000000080 0003c366c60c4501 0000000000000352
GPR08: 000000000001f400 0000000000000010 0000000000000000 0000000000000000
GPR12: 0001cf0000000019 c00000001ec97680 00000001003dfd40 0000010008dbb22c
GPR16: 0000000000000000 0000000000000000 0000000000000000 c000000000edb6c8
GPR20: c000000004e73e00 c000000004fd2448 c000000004e6d700 c000000004fd2448
GPR24: c000000004fd2400 c000000004a0cd20 c0000001ed961860 c0080000005029d8
GPR28: 0000000000000000 0000000000000003 c000000004a0c000 0000000000000000
NIP [c00800000050a900] init_resources+0x338/0xa00 [ibmvnic]
LR [c00800000050a8f0] init_resources+0x328/0xa00 [ibmvnic]
Call Trace:
[c0000001ed746fb0] [c00800000050a8f0] init_resources+0x328/0xa00 [ibmvnic] (unreliable)
[c0000001ed747090] [c00800000050b024] ibmvnic_open+0x5c/0x100 [ibmvnic]
[c0000001ed747110] [c000000000bdcc0c] __dev_open+0x17c/0x250
[c0000001ed7471b0] [c000000000bdd1ec] __dev_change_flags+0x1dc/0x270
[c0000001ed747260] [c000000000bdd2bc] dev_change_flags+0x3c/0x90
[c0000001ed7472a0] [c000000000bf24b8] do_setlink+0x3b8/0x1280
[c0000001ed747450] [c000000000bf8cc8] __rtnl_newlink+0x5a8/0x980
[c0000001ed7478b0] [c000000000bf9110] rtnl_newlink+0x70/0xb0
[c0000001ed7478f0] [c000000000bf07c4] rtnetlink_rcv_msg+0x364/0x460
[c0000001ed747990] [c000000000c68b94] netlink_rcv_skb+0x84/0x1a0
[c0000001ed747a00] [c000000000bef758] rtnetlink_rcv+0x28/0x40
[c0000001ed747a20] [c000000000c68188] netlink_unicast+0x218/0x310
[c0000001ed747a80] [c000000000c6848c] netlink_sendmsg+0x20c/0x4e0
[c0000001ed747b20] [c000000000b9dc88] ____sys_sendmsg+0x158/0x360
[c0000001ed747bb0] [c000000000ba1c88] ___sys_sendmsg+0x98/0xf0
[c0000001ed747d10] [c000000000ba1db8] __sys_sendmsg+0x78/0x100
[c0000001ed747dc0] [c000000000033820] system_call_exception+0x160/0x280
[c0000001ed747e20] [c00000000000d740] system_call_common+0xf0/0x27c
Instruction dump:
3be00000 38810068 b1410076 3941006a 93e10072 fbea0000 b1210068 4bff9915
eb9e0ca0 eabe0900 393c0010 3ab50048 <7fa04c2c> 7fba07b4 7b431764 7b4917a0
---[ end trace fbc5949a28e103bd ]---

Fixes: f3ae59c0c015 ("ibmvnic: store RX and TX subCRQ handle array in ibmvnic_adapter struct")
Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: store RX and TX subCRQ handle array in ibmvnic_adapter struct

Currently the driver reads RX and TX subCRQ handle array directly from
a DMA-mapped buffer address when it needs to make a H_SEND_SUBCRQ
hcall. This patch stores that information in the ibmvnic_sub_crq_queue
structure instead of reading from the buffer received at login. The
overall goal of this patch is to parse relevant information from the
login response buffer and store it in the driver's private data
structures so that we don't need to read directly from the buffer and
can then free up that memory.

Signed-off-by: Cristobal Forno <cforno12@linux.ibm.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Do not process device remove during device reset

The ibmvnic driver does not check the device state when the device
is removed. If the device is removed while a device reset is being
processed, the remove may free structures needed by the reset,
causing an oops.

Fix this by checking the device state before processing device remove.

Signed-off-by: Juliet Kim <julietk@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Serialize device queries

Provide some serialization for device CRQ commands
and queries to ensure that the shared variable used for
storing return codes is properly synchronized.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ibmvnic: prevent more than one thread from running in reset

The current code allows more than one thread to run in reset. This can
corrupt struct adapter data. Check adapter->resetting before performing
a reset, if there is another reset running delay (100 msec) before trying
again.

Signed-off-by: Juliet Kim <julietk@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ibmvnic: unlock rtnl_lock in reset so linkwatch_event can run

Commit a5681e20b541 ("net/ibmnvic: Fix deadlock problem in reset")
made the change to hold the RTNL lock during a reset to avoid deadlock
but linkwatch_event is fired during the reset and needs the RTNL lock.
That keeps linkwatch_event process from proceeding until the reset
is complete. The reset process cannot tolerate the linkwatch_event
processing after reset completes, so release the RTNL lock during the
process to allow a chance for linkwatch_event to run during reset.
This does not guarantee that the linkwatch_event will be processed as
soon as link state changes, but is an improvement over the current code
where linkwatch_event processing is always delayed, which prevents
transmissions on the device from being deactivated leading transmit
watchdog timer to time-out.

Release the RTNL lock before link state change and re-acquire after
the link state change to allow linkwatch_event to grab the RTNL lock
and run during the reset.

Fixes: a5681e20b541 ("net/ibmnvic: Fix deadlock problem in reset")
Signed-off-by: Juliet Kim <julietk@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 114

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 8 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091650.663497195@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net/ibmvnic: Update MAC address settings after adapter reset

It was discovered in testing that the underlying hardware MAC
address will revert to initial settings following a device reset,
but the driver fails to resend the current OS MAC settings. This
oversight can result in dropped packets should the scenario occur.
Fix this by informing hardware of current MAC address settings
following any adapter initialization or resets.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Add device identification to requested IRQs

The ibmvnic driver currently uses the same fixed name when using
request_irq, this makes it hard to parse when multiple VNIC devices are
available at the same time. This patch adds the unit_address as the device
identification along with an id for each queue.

The original idea was to use the interface name as an identifier, but it
is not feasible given these requests happen at adapter probe, and at this
point netdev is not yet registered so it doesn't have the proper name
assigned to it.

Signed-off-by: Murilo Fossa Vicentini <muvic@linux.ibm.com>
Reviewed-by: Mauro S. M. Rodrigues <maurosr@linux.vnet.ibm.com>
Reviewed-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Report actual backing device speed and duplex values

The ibmvnic driver currently reports a fixed value for both speed and
duplex settings regardless of the actual backing device that is being
used. By adding support to the QUERY_PHYS_PARMS command defined by the
PAPR+ we can query the current physical port state and report the proper
values for these feilds.

Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Signed-off-by: Murilo Fossa Vicentini <muvic@linux.ibm.com>
Reviewed-by: Mauro S. M. Rodrigues <maurosr@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Convert reset work item mutex to spin lock

ibmvnic_reset can create and schedule a reset work item from
an IRQ context, so do not use a mutex, which can sleep. Convert
the reset work item mutex to a spin lock. Locking debugger generated
the trace output below.

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:908
in_atomic(): 1, irqs_disabled(): 1, pid: 120, name: kworker/8:1
4 locks held by kworker/8:1/120:
#0: 0000000017c05720 ((wq_completion)"events"){+.+.}, at: process_one_work+0x188/0x710
#1: 00000000ace90706 ((linkwatch_work).work){+.+.}, at: process_one_work+0x188/0x710
#2: 000000007632871f (rtnl_mutex){+.+.}, at: rtnl_lock+0x30/0x50
#3: 00000000fc36813a (&(&crq->lock)->rlock){..-.}, at: ibmvnic_tasklet+0x88/0x2010 [ibmvnic]
irq event stamp: 26293
hardirqs last enabled at (26292): [<c000000000122468>] tasklet_action_common.isra.12+0x78/0x1c0
hardirqs last disabled at (26293): [<c000000000befce8>] _raw_spin_lock_irqsave+0x48/0xf0
softirqs last enabled at (26288): [<c000000000a8ac78>] dev_deactivate_queue.constprop.28+0xc8/0x160
softirqs last disabled at (26289): [<c0000000000306e0>] call_do_softirq+0x14/0x24
CPU: 8 PID: 120 Comm: kworker/8:1 Kdump: loaded Not tainted 4.20.0-rc6 #6
Workqueue: events linkwatch_event
Call Trace:
[c0000003fffa7a50] [c000000000bc83e4] dump_stack+0xe8/0x164 (unreliable)
[c0000003fffa7aa0] [c00000000015ba0c] ___might_sleep+0x2dc/0x320
[c0000003fffa7b20] [c000000000be960c] __mutex_lock+0x8c/0xb40
[c0000003fffa7c30] [d000000006202ac8] ibmvnic_reset+0x78/0x330 [ibmvnic]
[c0000003fffa7cc0] [d0000000062097f4] ibmvnic_tasklet+0x1054/0x2010 [ibmvnic]
[c0000003fffa7e00] [c0000000001224c8] tasklet_action_common.isra.12+0xd8/0x1c0
[c0000003fffa7e60] [c000000000bf1238] __do_softirq+0x1a8/0x64c
[c0000003fffa7f90] [c0000000000306e0] call_do_softirq+0x14/0x24
[c0000003f3f87980] [c00000000001ba50] do_softirq_own_stack+0x60/0xb0
[c0000003f3f879c0] [c0000000001218a8] do_softirq+0xa8/0x100
[c0000003f3f879f0] [c000000000121a74] __local_bh_enable_ip+0x174/0x180
[c0000003f3f87a60] [c000000000bf003c] _raw_spin_unlock_bh+0x5c/0x80
[c0000003f3f87a90] [c000000000a8ac78] dev_deactivate_queue.constprop.28+0xc8/0x160
[c0000003f3f87ad0] [c000000000a8c8b0] dev_deactivate_many+0xd0/0x520
[c0000003f3f87b70] [c000000000a8cd40] dev_deactivate+0x40/0x60
[c0000003f3f87ba0] [c000000000a5e0c4] linkwatch_do_dev+0x74/0xd0
[c0000003f3f87bd0] [c000000000a5e694] __linkwatch_run_queue+0x1a4/0x1f0
[c0000003f3f87c30] [c000000000a5e728] linkwatch_event+0x48/0x60
[c0000003f3f87c50] [c0000000001444e8] process_one_work+0x238/0x710
[c0000003f3f87d20] [c000000000144a48] worker_thread+0x88/0x4e0
[c0000003f3f87db0] [c00000000014e3a8] kthread+0x178/0x1c0
[c0000003f3f87e20] [c00000000000bfd0] ret_from_kernel_thread+0x5c/0x6c

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ibmnvic: Fix deadlock problem in reset

This patch changes to use rtnl_lock only during a reset to avoid
deadlock that could occur when a thread operating close is holding
rtnl_lock and waiting for reset_lock acquired by another thread,
which is waiting for rtnl_lock in order to set the number of tx/rx
queues during a reset.

Also, we now setting the number of tx/rx queues during a soft reset
for failover or LPM events.

Signed-off-by: Juliet Kim <julietk@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Add ethtool private flag for driver-defined queue limits

When choosing channel amounts and ring sizes, the maximums in the
ibmvnic driver are defined by the virtual i/o server management
partition. Even though they are defined as maximums, the client
driver may in fact successfully request resources that exceed
these limits, which are mostly dependent on a user's hardware

With this in mind, provide an ethtool flag that when enabled will
allow the user to request resources limited by driver-defined
maximums instead of limits defined by the management partition.
The driver will try to honor the user's request but may not allowed
by the management partition. In this case, the driver requests
as close as it can get to the desired amount until it succeeds.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Introduce driver limits for ring sizes

Introduce driver-defined maximums for queue ring sizes. Devices
available for IBM vNIC today will likely not allow this amount,
but this should give us some leeway for future devices that may
support larger ring sizes.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Increase maximum queue size limit

Increase queue size limit to 16. Devices available for IBM vNIC today
will not allow this amount, but this should give us some leeway for
future devices that may support more RX or TX queues.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Remove code to request error information

When backing device firmware reports an error, it provides an
error ID, which is meant to be queried for more detailed error
information. Currently, however, an error ID is not provided by
the Virtual I/O server and there are not any plans to do so. For
now, it is always unfilled or zero, so request_error_information
will never be called. Remove it.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Introduce hard reset recovery

Introduce a recovery hard reset to handle reset failure as a result of
change of device context following a transport event, such as a
backing device failover or partition migration. These operations reset
the device context to its initial state. If this occurs during a reset,
any initialization commands are likely to fail with an invalid state
error as backing device firmware requests reinitialization.

When this happens, make one more attempt by performing a hard reset,
which frees any resources currently allocated and performs device
initialization. If a transport event occurs during a device reset, a
flag is set which will trigger a new hard reset following the
completionof the current reset event.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Introduce active CRQ state

Introduce an "active" state for a IBM vNIC Command-Response Queue. A CRQ
is considered active once it has initialized or linked with its partner by
sending an initialization request and getting a successful response back
from the management partition. Until this has happened, do not allow CRQ
commands to be sent other than the initialization request.

This change will avoid a protocol error in case of a device transport
event occurring during a initialization. When the driver receives a
transport event notification indicating that the backing hardware
has changed and needs reinitialization, any further commands other
than the initialization handshake with the VIOS management partition
will result in an invalid state error. Instead of sending a command
that will be returned with an error, print a warning and return an
error that will be handled by the caller.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Handle all login error conditions

There is a bug in handling the possible return codes from sending the
login CRQ. The current code treats any non-success return value,
minus failure to send the crq and a timeout waiting for a login response,
as a need to re-send the login CRQ. This can put the drive in an
infinite loop of trying to login when getting return values other
that a partial success such as a return code of aborted. For these
scenarios the login will not ever succeed at this point and the
driver would need to be reset again.

To resolve this loop trying to login is updated to only retry the
login if the driver gets a return code of a partial success. Other
return codes are treated as an error and the driver returns an error
from ibmvnic_login().

To avoid infinite looping in the partial success return cases, the
number of retries is capped at the maximum number of supported
queues. This value was chosen because the driver does a renegotiation
of capabilities which sets the number of queues possible and allows
the driver to attempt a login for possible value for the number
of queues supported.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix failover case for non-redundant configuration

There is a failover case for a non-redundant pseries VNIC
configuration that was not being handled properly. The current
implementation assumes that the driver will always have a redandant
device to communicate with following a failover notification. There
are cases, however, when a non-redundant configuration can receive
a failover request. If that happens, the driver should wait until
it receives a signal that the device is ready for operation.

The driver is agnostic of its backing hardware configuration,
so this fix necessarily affects all device failover management.
The driver needs to wait until it receives a signal that the device
is ready for resetting. A flag is introduced to track this intermediary
state where the driver is waiting for an active device.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Remove unused TSO resources in TX pool structure

Finally, remove the TSO-specific fields in the TX pool
strcutures. These are no longer needed with the introduction
of separate buffer pools for TSO transmissions.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Update TX and TX completion routines

Update TX and TX completion routines to account for TX pool
restructuring. TX routine first chooses the pool depending
on whether a packet is GSO or not, then uses it accordingly.

For the completion routine to know which pool it needs to use,
set the most significant bit of the correlator index to one
if the packet uses the TSO pool. On completion, unset the bit
and use the correlator index to release the buffer pool entry.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Generalize TX pool structure

Remove some unused fields in the structure and include values
describing the individual buffer size and number of buffers in
a TX pool. This allows us to use these fields for TX pool buffer
accounting as opposed to using hard coded values. Include a new
pool array for TSO transmissions.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Split counters for scrq/pools/napi

The approach of one counter to rule them all when tracking the number
of active sub-crqs, pools, and napi has problems handling some failover
scenarios. This is due to the split in initializing the sub crqs,
pools and napi in different places and the placement of updating
the active counts.

This patch simplifies this by having a counter for tx and rx
sub-crqs, pools, and napi.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Rename active queue count variables

Rename the tx/rx active pool variables to be tx/rx active scrq
counts. The tx/rx pools are per sub-crq so this is a more appropriate
name. This also is a preparatory step for using thiese variables
for handling updates to sub-crqs and napi based on the active
count.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Keep track of supplementary TX descriptors

Supplementary TX descriptors were not being accounted for, which
was resulting in an overflow of the hardware device's transmit
queue. Keep track of those descriptors now when determining
how many entries remain on the TX queue.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Modify buffer size and number of queues on failover

Using newer backing devices can cause the required padding at the end of
buffer as well as the number of queues to change after a failover.
Since we currently assume that these values never change, after a
failover to a backing device with different capabilities, we can get
errors from the vnic server, attempt to free long term buffers that are
no longer there, or not free long term buffers that should be freed.

This patch resolves the issue by checking whether any of these values
change, and if so perform the necessary re-allocations.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Increase maximum number of RX/TX queues

Increase the number of queues allocated to accommodate recent
network adapter inclusions on the IBM vNIC platform.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Rename IBMVNIC_MAX_TX_QUEUES to IBMVNIC_MAX_QUEUES

This value denotes the maximum number of TX queues but is used
to allocate both RX and TX queues.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Feature implementation of Vital Product Data (VPD) for the ibmvnic driver

This patch implements and enables VDP support for the ibmvnic driver.
Moreover, it includes the implementation of suitable structs, signal
transmission/handling and functions which allows the retrival of firmware
information from the ibmvnic card through the ethtool command.

Signed-off-by: Desnes A. Nunes do Rosario <desnesn@linux.vnet.ibm.com>
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Add vnic client data to login buffer

Update the login buffer to include client data for the vnic driver,
this includes the OS name, LPAR name, and device name. This update
allows this information to be available in the VIOS.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix failover error path for non-fatal resets

For all non-fatal reset conditions, the hypervisor will send a failover when
we attempt to initialize the crq and the vnic client is expected to handle
that failover instead of the existing non-fatal reset. To handle this, we
need to return from init with a return code that indicates that we have hit
this case.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Update reset infrastructure to support tunable parameters

Update ibmvnic reset infrastructure to include a new reset option that will
allow changing of tunable parameters. There currently is no way to request
different capabilities from the vnic server on the fly so this patch
achieves this by resetting the driver and attempting to log in with the
requested changes. If the reset operation fails, the old values of the
tunable parameters are stored in the "fallback" struct and we attempt to
login with the fallback values.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Enable TSO support

This patch enables TSO support. It includes additional
buffers reserved exclusively for large packets. Throughput
is greatly increased with TSO enabled, from about 1 Gb/s to
9 Gb/s on our test systems.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Implement per-queue statistics reporting

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: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix error handling when registering long-term-mapped buffers

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: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix incorrectly defined ibmvnic_request_map_rsp structure

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: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Non-fatal error handling

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: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Handle failover after failed init crq

Handle case where phyp sends a failover after failing to send the
init crq.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Track state of adapter napis

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: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Updated reset handling

The ibmvnic driver has multiple handlers for resetting the driver
depending on the reason the reset is needed (failover, lpm,
fatal erors,...). All of the reset handlers do essentially the same
thing, this patch moves this work to a common reset handler.

By doing this we also allow the driver to better handle situations
where we can get a reset while handling a reset.

The updated reset handling works by adding a reset work item to the
list of resets and then scheduling work to perform the reset. This
step is necessary because we can receive a reset in interrupt context
and we want to handle the reset out of interrupt context.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Replace is_closed with state field

Replace the is_closed flag in the ibmvnic adapter strcut with a
more comprehensive state field that tracks the current state of
the driver.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Add set_link_state routine for setting adapter link state

Create a common routine for setting the link state for the vnic adapter.
This update moves the sending of the crq and waiting for the link state
response to a common place. The new routine also adds handling of
resending the crq in cases of getting a partial success response.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Insert header on VLAN tagged received frame

This patch addresses a modification in the PAPR+ specification which now
defines a previously reserved value for vNIC capabilities. It indicates
whether the system firmware performs a VLAN header stripping on all VLAN
tagged received frames, in case it does, the behavior expected is for
the ibmvnic driver to be responsible for inserting the VLAN header.

Reported-by: Manvanthara B. Puttashankar <mputtash@in.ibm.com>
Signed-off-by: Murilo Fossa Vicentini <muvic@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Remove unused bouce buffer

The bounce buffer is not used in the ibmvnic driver, just
get rid of it.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Remove inflight list

The inflight list used to track memory that is allocated for crq that are
inflight is not needed. The one piece of the inflight list that does need
to be cleaned at module exit is the error buffer list which is already
attached to the adapter struct.

This patch removes the inflight list and moves checking the error buffer
list to ibmvnic_remove.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix ibmvnic_change_mac_addr struct format

The ibmvnic_change_mac_addr struct alignment was not matching the defined
format in PAPR+, it had the reserved and return code fields swapped. As a
consequence, the CHANGE_MAC_ADDR_RSP commands were being improperly handled
and executed even when the operation wasn't successfully completed by the
system firmware.

Also changing the endianness of the debug message to make it easier to
parse the CRQ content.

Signed-off-by: Murilo Fossa Vicentini <muvic@linux.vnet.ibm.com>
Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Remove debugfs support

The debugfs support in the ibmvnic driver is not, and never has been,
supported. Just remove it.

The work done in the debugfs code for the driver was part of the original
spec for the ibmvnic driver. The corresponding support for this from the
server side was never supported and has been dropped.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ibmvnic: Remove unused net_stats member from struct ibmvnic_adapter

The ibmvnic driver keeps its statistics in net_device->stats, so the
net_stats member in struct ibmvnic_adapter is unused. Remove it.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Correct ibmvnic handling of device open/close

When closing the ibmvnic device we need to release the resources used
in communicating to the virtual I/O server. These need to be
re-negotiated with the server at open time.

This patch moves the releasing of resources a separate routine
and updates the open and close handlers to release all resources at
close and re-negotiate and allocate these resources at open.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix overflowing firmware/hardware TX queue

Use a counter to track the number of outstanding transmissions sent
that have not received completions. If the counter reaches the maximum
number of queue entries, stop transmissions on that queue. As we receive
more completions from firmware, wake the queue once the counter reaches
an acceptable level.

This patch prevents hardware/firmware TX queue from filling up and
and generating errors. Since incorporating this fix, internal testing
has reported that these firmware errors have stopped.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Make CRQ interrupt tasklet wait for all capabilities crqs

After sending device capability queries and requests to the vNIC Server,
an interrupt is triggered and the responses are written to the driver's
CRQ response buffer. Since the interrupt can be triggered before all
responses are written and visible to the partition, there is a danger
that the interrupt handler or tasklet can terminate before all responses
are read, resulting in a failure to initialize the device.

To avoid this scenario, when capability commands are sent, we set
a flag that will be checked in the following interrupt tasklet that
will handle the capability responses from the server. Once all
responses have been handled, the flag is disabled; and the tasklet
is allowed to terminate.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Use common counter for capabilities checks

Two different counters were being used for capabilities
requests and queries. These commands are not called
at the same time so there is no reason a single counter
cannot be used.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Handle processing of CRQ messages in a tasklet

Create a tasklet to process queued commands or messages received from
firmware instead of processing them in the interrupt handler. Note that
this handler does not process network traffic, but communications related
to resource allocation and device settings.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context

Schedule these XPORT event tasks in the shared workqueue
so that IRQs are not freed in an interrupt context when
sub-CRQs are released.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Revert "ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context"

This reverts commit 8d7533e5aaad1c94386a8101a36b0617987966b7.

It introduced kbuild failures, new version coming.

Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context

Schedule these XPORT event tasks in the shared workqueue
so that IRQs are not freed in an interrupt context when
sub-CRQs are released.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Driver Version 1.0.1

Increment driver version to reflect features that have
been added since release.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Handle backing device failover and reinitialization

An upcoming feature of IBM VNIC protocol is the ability to configure
redundant backing devices for a VNIC client. In case of a failure
on the current backing device, the driver will receive a signal
from the hypervisor indicating that a failover will occur. The driver
will then wait for a message from the backing device before
establishing a new connection.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix passive VNIC server login process

In some cases, if there is no VNIC server available during the driver
probe, the driver should wait until it receives an initialization
request from the VNIC Server to start the login process. Recent testing
has show that this is incorrectly handled in the current driver.

The proposed solution handles this initialization request by scheduling
a task in the shared workqueue that completes the login process and
registers the net device.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Enable use of multiple tx/rx scrqs

Enables the use of multiple transmit and receive scrqs allowing the ibmvnic
driver to take advantage of multiqueue functionality. To achieve this, the
driver must implement the process of negotiating the maximum number of
queues allowed by the server. Initially, the driver will attempt to login
with the maximum number of tx and rx queues supported by the server. If
the server fails to allocate the requested number of scrqs, it will return
partial success in the login response. In this case, we must reinitiate
the login process from the request capabilities stage and attempt to login
requesting fewer scrqs.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: map L2/L3/L4 header descriptors to firmware

Allow the VNIC driver to provide descriptors containing
L2/L3/L4 headers to firmware. This feature is needed
for greater hardware compatibility and enablement of checksum
and TCP offloading features.

A new function is included for the hypervisor call,
H_SEND_SUBCRQ_INDIRECT, allowing a DMA-mapped array of SCRQ
descriptor elements to be sent to the VNIC server.

These additions will help fully enable checksum offloading as
well as other features as they are included later.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Cc: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ibmvnic: Fix ibmvnic_capability struct

The ibmvnic_capability struct was defined incorrectly. The last two
elements of the struct are in the wrong order. In addition, the number
element should be 64-bit. Byteswapping functions are updated
as well.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Driver for IBM System i/p VNIC protocol

This is a new device driver for a high performance SR-IOV assisted virtual
network for IBM System p and IBM System i systems. The SR-IOV VF will be
attached to the VIOS partition and mapped to the Linux client via the
hypervisor's VNIC protocol that this driver implements.

This driver is able to perform basic tx and rx, new features
and improvements will be added as they are being developed and tested.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>