IB/IPoIB: Allow using netdevs that require the instance lock

IB/IPoIB: Allow using netdevs that require the instance lock

After the last patch removing vlan_rwsem, it is an incremental step to
allow ipoib to work with netdevs that require the instance lock.
In several places, netdev_lock() is changed to netdev_lock_ops_to_full()
which takes care of not acquiring the lock again when the netdev is
already locked.

In ipoib_ib_tx_timeout_work() and __ipoib_ib_dev_flush() for HEAVY
flushes, the netdev lock is acquired/released. This is needed because
these functions end up calling .ndo_stop()/.ndo_open() on subinterfaces,
and the device may expect the netdev instance lock to be held.

ipoib_set_mode() now explicitly acquires ops lock while manipulating the
features, mtu and tx queues.

Finally, ipoib_napi_enable()/ipoib_napi_disable() now use the *_locked
variants of the napi_enable()/napi_disable() calls and optionally
acquire the netdev lock themselves depending on the dev they operate on.

Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/1747829342-1018757-4-git-send-email-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>