infiniband: i40iw, nes: don't use wall time for TCP sequence numbers

The nes infiniband driver uses current_kernel_time() to get a nanosecond
granunarity timestamp to initialize its tcp sequence counters. This is
one of only a few remaining users of that deprecated function, so we
should try to get rid of it.

Aside from using a deprecated API, there are several problems I see here:

- Using a CLOCK_REALTIME based time source makes it predictable in
  case the time base is synchronized.
- Using a coarse timestamp means it only gets updated once per jiffie,
  making it even more predictable in order to avoid having to access
  the hardware clock source
- The upper 2 bits are always zero because the nanoseconds are at most
  999999999.

For the Linux TCP implementation, we use secure_tcp_seq(), which appears
to be appropriate here as well, and solves all the above problems.

i40iw uses a variant of the same code, so I do that same thing there
for ipv4. Unlike nes, i40e also supports ipv6, which needs to call
secure_tcpv6_seq instead.

Acked-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/i40iw/Kconfig b/drivers/infiniband/hw/i40iw/Kconfig
index 2962979c06e9..d867ef1ac72a 100644
--- a/drivers/infiniband/hw/i40iw/Kconfig
+++ b/drivers/infiniband/hw/i40iw/Kconfig
@@ -1,6 +1,7 @@
 config INFINIBAND_I40IW
 	tristate "Intel(R) Ethernet X722 iWARP Driver"
 	depends on INET && I40E
+	depends on IPV6 || !IPV6
 	depends on PCI
 	select GENERIC_ALLOCATOR
 	---help---