Commit 86dabda426 ("net: thunderbolt: Clear finished Tx frame bus
address in tbnet_tx_callback()") fixed a DMA-API violation where the
driver called dma_unmap_page() in tbnet_free_buffers() for a bus address
that might already be unmapped. The fix was to zero out the bus address
of a frame in tbnet_tx_callback().
However, as pointed out by David Miller, zero might well be valid
mapping (at least in theory) so it is not good idea to use it here.
It turns out that we don't need the whole map/unmap dance for Tx buffers
at all. Instead we can map the buffers when they are initially allocated
and unmap them when the interface is brought down. In between we just
DMA sync the buffers for the CPU or device as needed.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When Thunderbolt network interface is disabled or when the cable is
unplugged the driver releases all allocated buffers by calling
tbnet_free_buffers() for each ring. This function then calls
dma_unmap_page() for each buffer it finds where bus address is non-zero.
Now, we only clear this bus address when the Tx buffer is sent to the
hardware so it is possible that the function finds an entry that has
already been unmapped.
Enabling DMA-API debugging catches this as well:
thunderbolt 0000:06:00.0: DMA-API: device driver tries to free DMA
memory it has not allocated [device address=0x0000000068321000] [size=4096 bytes]
Fix this by clearing the bus address of a Tx frame right after we have
unmapped the buffer.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a problem when we do:
sequence = pkg->hdr.length_sn & TBIP_HDR_SN_MASK;
sequence >>= TBIP_HDR_SN_SHIFT;
TBIP_HDR_SN_SHIFT is 27, and right shifting a u8 27 bits is always
going to result in zero. The fix is to declare these variables as u32.
Fixes: e69b6c02b4 ("net: Add support for networking over Thunderbolt cable")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ThunderboltIP is a protocol created by Apple to tunnel IP/ethernet
traffic over a Thunderbolt cable. The protocol consists of configuration
phase where each side sends ThunderboltIP login packets (the protocol is
determined by UUID in the XDomain packet header) over the configuration
channel. Once both sides get positive acknowledgment to their login
packet, they configure high-speed DMA path accordingly. This DMA path is
then used to transmit and receive networking traffic.
This patch creates a virtual ethernet interface the host software can
use in the same way as any other networking interface. Once the
interface is brought up successfully network packets get tunneled over
the Thunderbolt cable to the remote host and back.
The connection is terminated by sending a ThunderboltIP logout packet
over the configuration channel. We do this when the network interface is
brought down by user or the driver is unloaded.
Signed-off-by: Amir Levy <amir.jer.levy@intel.com>
Signed-off-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
