This reverts commit d437f5aa.

Code has been duplicated through commit <273c29e9> "ibmvnic: check
failover_pending in login response"
Signed-off-by: NDesnes A. Nunes do Rosario <desnesn@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If a failover occurs before a login response is received, the login
response buffer maybe undefined. Check that there was no failover
before accessing the login response buffer.

Fixes: 032c5e82 ("Driver for IBM System i/p VNIC protocol")
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If a failover occurs before a login response is received, the login
response buffer maybe undefined. Check that there was no failover
before accessing the login response buffer.
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 65d6470d ("ibmvnic: clean pending indirect buffs during reset")
intended to remove the call to ibmvnic_tx_scrq_flush() when the
->resetting flag is true and was tested that way. But during the final
rebase to net-next, the hunk got applied to a block few lines below
(which happened to have the same diff context) and the wrong call to
ibmvnic_tx_scrq_flush() got removed.

Fix that by removing the correct ibmvnic_tx_scrq_flush() and restoring
the one that was incorrectly removed.

Fixes: 65d6470d ("ibmvnic: clean pending indirect buffs during reset")
Reported-by: NDany Madden <drt@linux.ibm.com>
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Normally, if a reset fails due to failover or other communication error
there is another reset (eg: FAILOVER) in the queue and we would process
that reset. But if we are unable to communicate with PHYP or VIOS after
H_FREE_CRQ, there would be no other resets in the queue and the adapter
would be in an undefined state even though it was in the OPEN state
earlier. While starting the reset we set the carrier to off state so
we won't even get the timeout resets.

If the last queued reset fails, retry it as a hard reset (after the
usual 60 second settling time).
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Reviewed-by: NDany Madden <drt@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Parenthesize a check to be more explicit and to fix a sparse warning
seen on some distros.

Fixes: 91dc5d25 ("ibmvnic: fix miscellaneous checks")
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Free tx_pool and clear it, if allocation of tso_pool fails.

release_tx_pools() assumes we have both tx and tso_pools if ->tx_pool is
non-NULL. If allocation of tso_pool fails in init_tx_pools(), the assumption
will not be true and we would end up dereferencing ->tx_buff, ->free_map
fields from a NULL pointer.

Fixes: 3205306c ("ibmvnic: Update TX pool initialization routine")
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

free_long_term_buff() checks ltb->buff to decide whether we have a long
term buffer to free. So set ltb->buff to NULL afer freeing. While here,
also clear ->map_id, fix up some coding style and log an error.

Fixes: 9c4eaabd ("Check CRQ command return codes")
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This fixes a crash in replenish_rx_pool() when called from ibmvnic_poll()
after a previous call to replenish_rx_pool() encountered an error when
allocating a socket buffer.

Thanks to Rick Lindsley and Dany Madden for helping debug the crash.

Fixes: 4f0b6812 ("ibmvnic: Introduce batched RX buffer descriptor transmission")
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We batch subordinate command response queue (scrq) descriptors that we
need to send to the VIOS using an "indirect" buffer. If after we queue
one or more scrqs in the indirect buffer encounter an error (say fail
to allocate an skb), we leave the queued scrq descriptors in the
indirect buffer until the next call to ibmvnic_xmit().

On the next call to ibmvnic_xmit(), it is possible that the adapter is
going through a reset and it is possible that the long term  buffers
have been unmapped on the VIOS side. If we proceed to flush (send) the
packets that are in the indirect buffer, we will end up using the old
map ids and this can cause the VIOS to trigger an unnecessary FATAL
error reset.

Instead of flushing packets remaining on the indirect_buff, discard
(clean) them instead.

Fixes: 0d973388 ("ibmvnic: Introduce xmit_more support using batched subCRQ hcalls")
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit 7c451f3e.

When a vnic interface is taken down and then up, connectivity is not
restored. We bisected it to this commit. Reverting this commit until
we can fully investigate the issue/benefit of the change.

Fixes: 7c451f3e ("ibmvnic: remove duplicate napi_schedule call in open function")
Reported-by: NCristobal Forno <cforno12@linux.ibm.com>
Reported-by: NAbdul Haleem <abdhalee@in.ibm.com>
Signed-off-by: NDany Madden <drt@linux.ibm.com>
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit 1c7d45e7.

We tried to optimize the number of hcalls we send and skipped sending
the REQUEST_MAP calls for some maps. However during resets, we need to
resend all the maps to the VIOS since the VIOS does not remember the
old values. In fact we may have failed over to a new VIOS which will
not have any of the mappings.

When we send packets with map ids the VIOS does not know about, it
triggers a FATAL reset. While the client does recover from the FATAL
error reset, we are seeing a large number of such resets. Handling
FATAL resets is lot more unnecessary work than issuing a few more
hcalls so revert the commit and resend the maps to the VIOS.

Fixes: 1c7d45e7 ("ibmvnic: simplify reset_long_term_buff function")
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since these strings are expected to be NUL-terminated and the buffers
are exactly sized (in vnic_client_data_len()) with no padding, strncpy()
can be safely replaced with strscpy() here, as strncpy() on
NUL-terminated string is considered deprecated[1]. This has the
side-effect of silencing a -Warray-bounds warning due to the compiler
being confused about the vlcd incrementing:

In file included from ./include/linux/string.h:253,
                 from ./include/linux/bitmap.h:10,
                 from ./include/linux/cpumask.h:12,
                 from ./include/linux/mm_types_task.h:14,
                 from ./include/linux/mm_types.h:5,
                 from ./include/linux/buildid.h:5,
                 from ./include/linux/module.h:14,
                 from drivers/net/ethernet/ibm/ibmvnic.c:35:
In function '__fortify_strncpy',
    inlined from 'vnic_add_client_data' at drivers/net/ethernet/ibm/ibmvnic.c:3919:2:
./include/linux/fortify-string.h:39:30: warning: '__builtin_strncpy' offset 12 from the object at 'v
lcd' is out of the bounds of referenced subobject 'name' with type 'char[]' at offset 12 [-Warray-bo
unds]
   39 | #define __underlying_strncpy __builtin_strncpy
      |                              ^
./include/linux/fortify-string.h:51:9: note: in expansion of macro '__underlying_strncpy'
   51 |  return __underlying_strncpy(p, q, size);
      |         ^~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/ibm/ibmvnic.c: In function 'vnic_add_client_data':
drivers/net/ethernet/ibm/ibmvnic.c:3883:7: note: subobject 'name' declared here
 3883 |  char name[];
      |       ^~~~

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings

Cc: Dany Madden <drt@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Cc: Thomas Falcon <tlfalcon@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The 3rd argument is u32 by function definition while it is __be32
by function declaration.
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix the following kernel build warnings:
drivers/net/ethernet/ibm/ibmvnic.c:1516: warning: Function parameter or member 'skb' not described in 'build_hdr_descs_arr'
drivers/net/ethernet/ibm/ibmvnic.c:1516: warning: Function parameter or member 'indir_arr' not described in 'build_hdr_descs_arr'
drivers/net/ethernet/ibm/ibmvnic.c:1516: warning: Excess function parameter 'txbuff' description in 'build_hdr_descs_arr'
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/ibm/ibmvnic.c: In function ‘adapter_state_to_string’:
drivers/net/ethernet/ibm/ibmvnic.c:855:2: warning: enumeration value ‘VNIC_DOWN’ not handled in switch [-Wswitch]
  855 |  switch (state) {
      |  ^~~~~~
drivers/net/ethernet/ibm/ibmvnic.c: In function ‘reset_reason_to_string’:
drivers/net/ethernet/ibm/ibmvnic.c:1958:2: warning: enumeration value ‘VNIC_RESET_PASSIVE_INIT’ not handled in switch [-Wswitch]
 1958 |  switch (reason) {
      |  ^~~~~~
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/ibm/ibmvnic.c: In function ‘handle_vpd_rsp’:
drivers/net/ethernet/ibm/ibmvnic.c:4393:3: warning: ‘strncpy’ output truncated before terminating nul copying 3 bytes from a string of the same length [-Wstringop-truncation]
 4393 |   strncpy((char *)adapter->fw_version, "N/A", 3 * sizeof(char));
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NThomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: NThomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: NCristobal Forno <cforno12@linux.ibm.com>
Acked-by: NLijun Pan <lijunp213@gmail.com>
Reviewed-by: NDany Madden <drt@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert list_for_each() to list_for_each_entry() where
applicable. This simplifies the code.
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NWang Hai <wanghai38@huawei.com>
Acked-by: NLijun Pan <lijunp213@gmail.com>
Reviewed-by: NDany Madden <drt@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This way the compiler warns when a new value is added to the enum but
not to the string translation like:

drivers/net/ethernet/ibm/ibmvnic.c: In function 'adapter_state_to_string':
drivers/net/ethernet/ibm/ibmvnic.c:832:2: warning: enumeration value 'VNIC_FOOBAR' not handled in switch [-Wswitch]
  switch (state) {
  ^~~~~~
drivers/net/ethernet/ibm/ibmvnic.c: In function 'reset_reason_to_string':
drivers/net/ethernet/ibm/ibmvnic.c:1935:2: warning: enumeration value 'VNIC_RESET_FOOBAR' not handled in switch [-Wswitch]
  switch (reason) {
  ^~~~~~
Signed-off-by: NMichal Suchanek <msuchanek@suse.de>
Acked-by: NLijun Pan <lijunp213@gmail.com>
Link: https://lore.kernel.org/netdev/CAOhMmr701LecfuNM+EozqbiTxFvDiXjFdY2aYeKJYaXq9kqVDg@mail.gmail.com/Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove the unnecessary napi_schedule() call in __ibmvnic_open() since
interrupt_rx() calls napi_schedule_prep/__napi_schedule during every
receive interrupt.

Fixes: ed651a10 ("ibmvnic: Updated reset handling")
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

During adapter reset, do_reset/do_hard_reset calls ibmvnic_open(),
which will calls napi_schedule if previous state is VNIC_CLOSED
(i.e, the reset case, and "ifconfig down" case). So there is no need
for do_reset to call napi_schedule again at the end of the function
though napi_schedule will neglect the request if napi is already
scheduled.

Fixes: ed651a10 ("ibmvnic: Updated reset handling")
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

__ibmvnic_open calls napi_disable without checking whether NAPI polling
has already been disabled or not. This could cause napi_disable
being called twice, which could generate deadlock. For example,
the first napi_disable will spin until NAPI_STATE_SCHED is cleared
by napi_complete_done, then set it again.
When napi_disable is called the second time, it will loop infinitely
because no dev->poll will be running to clear NAPI_STATE_SCHED.

To prevent above scenario from happening, call ibmvnic_napi_disable()
which checks if napi is disabled or not before calling napi_disable.

Fixes: bfc32f29 ("ibmvnic: Move resource initialization to its own routine")
Suggested-by: NThomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The reset process for ibmvnic commonly takes multiple seconds, clearly
making it inappropriate for schedule_work/system_wq. The reason to make
this change is that ibmvnic's use of the default system-wide workqueue
for a relatively long-running work item can negatively affect other
workqueue users. So, queue the relatively slow reset job to the
system_long_wq.
Suggested-by: NNathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is more correct to use dev_kfree_skb_irq when packets are dropped,
and to use dev_consume_skb_irq when packets are consumed.

Fixes: 0d973388 ("ibmvnic: Introduce xmit_more support using batched subCRQ hcalls")
Suggested-by: NThomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current implementation relies on H_IOCTL call to issue a
H_SESSION_ERR_DETECTED command to let the hypervisor to send a failover
signal. However, it may not work if there is no backup device or if
the vnic is already in error state,
e.g., "ibmvnic 30000003 env3: rx buffer returned with rc 6".
Add a last resort, that is to schedule a failover reset via CRQ command.
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The adapter state can be added or deleted over different versions
of the source code. Print a string instead of a number.
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The reset reason can be added or deleted over different versions
of the source code. Print a string instead of a number.
Signed-off-by: NLijun Pan <lijunp213@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

'page_address(skb_frag_page()) + skb_frag_off()' can be replaced by an
equivalent 'skb_frag_address()' which is less verbose.
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ibmvnic_remove locks multiple spinlocks while disabling interrupts:
spin_lock_irqsave(&adapter->state_lock, flags);
spin_lock_irqsave(&adapter->rwi_lock, flags);

As reported by coccinelle, the second _irqsave() overwrites the value
saved in 'flags' by the first _irqsave(),   therefore when the second
_irqrestore() comes,the value in 'flags' is not valid,the value saved
by the first _irqsave() has been lost.
This likely leads to IRQs remaining disabled. So remove the second
_irqsave():
spin_lock_irqsave(&adapter->state_lock, flags);
spin_lock(&adapter->rwi_lock);

Generated by: ./scripts/coccinelle/locks/flags.cocci
./drivers/net/ethernet/ibm/ibmvnic.c:5413:1-18:
ERROR: nested lock+irqsave that reuses flags from line 5404.

Fixes: 4a41c421 ("ibmvnic: serialize access to work queue on remove")
Signed-off-by: NJunlin Yang <yangjunlin@yulong.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The last change to ibmvnic_set_mac(), 8fc3672a, meant to prevent
users from setting an invalid MAC address on an ibmvnic interface
that has not been brought up yet. The change also prevented the
requested MAC address from being stored by the adapter object for an
ibmvnic interface when the state of the ibmvnic interface is
VNIC_PROBED - that is after probing has finished but before the
ibmvnic interface is brought up. The MAC address stored by the
adapter object is used and sent to the hypervisor for checking when
an ibmvnic interface is brought up.

The ibmvnic driver ignoring the requested MAC address when in
VNIC_PROBED state caused LACP bonds (bonds in 802.3ad mode) with more
than one slave to malfunction. The bonding code must be able to
change the MAC address of its slaves before they are brought up
during enslaving. The inability of kernels with 8fc3672a to set
the MAC addresses of bonding slaves is observable in the output of
"ip address show". The MAC addresses of the slaves are the same as
the MAC address of the bond on a working system whereas the slaves
retain their original MAC addresses on a system with a malfunctioning
LACP bond.

Fixes: 8fc3672a ("ibmvnic: fix ibmvnic_set_mac")
Signed-off-by: NJiri Wiesner <jwiesner@suse.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

GCC 7.5 reports:
../drivers/net/ethernet/ibm/ibmvnic.c: In function 'ibmvnic_reset_init':
../drivers/net/ethernet/ibm/ibmvnic.c:5373:51: warning: 'old_num_tx_queues' may be used uninitialized in this function [-Wmaybe-uninitialized]
../drivers/net/ethernet/ibm/ibmvnic.c:5373:6: warning: 'old_num_rx_queues' may be used uninitialized in this function [-Wmaybe-uninitialized]

The variable is initialized only if(reset) and used only if(reset &&
something) so this is a false positive. However, there is no reason to
not initialize the variables unconditionally avoiding the warning.

Fixes: 635e442f ("ibmvnic: merge ibmvnic_reset_init and ibmvnic_init")
Signed-off-by: NMichal Suchanek <msuchanek@suse.de>
Reviewed-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core ignores the return value of struct bus_type::remove()
because there is only little that can be done. To simplify the quest to
make this function return void, let struct vio_driver::remove() return
void, too. All users already unconditionally return 0, this commit makes
it obvious that returning an error code is a bad idea.

Note there are two nominally different implementations for a vio bus:
one in arch/sparc/kernel/vio.c and the other in
arch/powerpc/platforms/pseries/vio.c. This patch only adapts the powerpc
one.

Before this patch for a device that was bound to a driver without a
remove callback vio_cmo_bus_remove(viodev) wasn't called. As the device
core still considers the device unbound after vio_bus_remove() returns
calling this unconditionally is the consistent behaviour which is
implemented here.
Signed-off-by: NUwe Kleine-König <uwe@kleine-koenig.org>
Reviewed-by: NTyrel Datwyler <tyreld@linux.ibm.com>
Acked-by: NLijun Pan <ljp@linux.ibm.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
[mpe: Drop unneeded hvcs_remove() forward declaration, squash in
 change from sfr to drop ibmvnic_remove() forward declaration]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210225221834.160083-1-uwe@kleine-koenig.org

__ibmvnic_reset() currently reads the adapter->state before getting the
rtnl and saves that state as the "target state" for the reset. If this
read occurs when adapter is in PROBED state, the target state would be
PROBED.

Just after the target state is saved, and before the actual reset process
is started (i.e before rtnl is acquired) if we get an ibmvnic_open() call
we would move the adapter to OPEN state.

But when the reset is processed (after ibmvnic_open()) drops the rtnl),
it will leave the adapter in PROBED state even though we already moved
it to OPEN.

To fix this, use the RTNL to improve serialization when reading/updating
the adapter state. i.e determine the target state of a reset only after
getting the RTNL. And if a reset is in progress during an open, simply
set the target state of the adapter and let the reset code finish the
open (like we currently do if failover is pending).

One twist to this serialization is if the adapter state changes when we
drop the RTNL to update the link state. Account for this by checking if
there was an intervening open and update the target state for the reset
accordingly (see new comments in the code). Note that only the reset
functions and ibmvnic_open() can set the adapter to OPEN state and this
must happen under rtnl.

Fixes: 7d7195a0 ("ibmvnic: Do not process device remove during device reset")
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Reviewed-by: NDany Madden <drt@linux.ibm.com>
Link: https://lore.kernel.org/r/20210224050229.1155468-1-sukadev@linux.ibm.comSigned-off-by: NJakub Kicinski <kuba@kernel.org>

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

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: 6954a9e4 ("ibmvnic: Flush existing work items before device removal")
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.ibm.com>
Cc:Uwe Kleine-König <uwe@kleine-koenig.org>
Cc:Saeed Mahameed <saeed@kernel.org>
Reviewed-by: NDany Madden <drt@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Timeout reset will trigger the VIOS to unmap it automatically,
similarly as FAILVOER and MOBILITY events. If we unmap it
in the linux side, we will see errors like
"30000003: Error 4 in REQUEST_UNMAP_RSP".
So, don't call send_request_unmap for timeout reset.

Fixes: ed651a10 ("ibmvnic: Updated reset handling")
Signed-off-by: NLijun Pan <ljp@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

dma_rmb() barrier is added to load the long term buffer before copying
it to socket buffer; and dma_wmb() barrier is added to update the
long term buffer before it being accessed by VIOS (virtual i/o server).

Fixes: 032c5e82 ("Driver for IBM System i/p VNIC protocol")
Signed-off-by: NLijun Pan <ljp@linux.ibm.com>
Acked-by: NThomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The CRQ and subCRQ descriptors are DMA mapped, so dma_wmb(),
though weaker, is good enough to protect the data structures.
Signed-off-by: NLijun Pan <ljp@linux.ibm.com>
Acked-by: NThomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only thing reset_long_term_buff() should do is set
buffer to zero. After doing that, it is not necessary to
send_request_map again to VIOS since it actually does not
change the mapping. So, keep memset function and remove all
others.
Signed-off-by: NLijun Pan <ljp@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>