Re: [PATCH v1] RDMA/core: Handle ARPHRD_NONE devices for iWARP

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



在 2023/6/10 20:05, Jason Gunthorpe 写道:
On Fri, Jun 09, 2023 at 04:49:49PM -0400, Tom Talpey wrote:
On 6/7/2023 3:43 PM, Chuck Lever wrote:
From: Chuck Lever <chuck.lever@xxxxxxxxxx>

We would like to enable the use of siw on top of a VPN that is
constructed and managed via a tun device. That hasn't worked up
until now because ARPHRD_NONE devices (such as tun devices) have
no GID for the RDMA/core to look up.

But it turns out that the egress device has already been picked for
us. addr_handler() just has to do the right thing with it.

Tested with siw and qedr, both initiator and target.

Suggested-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
   drivers/infiniband/core/cma.c |    3 +++
   1 file changed, 3 insertions(+)

This of course needs broader testing, but it seems to work, and it's
a little nicer than "if (dev_type == ARPHRD_NONE)".

One thing I discovered is that the NFS/RDMA server implementation
does not deal at all with more than one RDMA device on the system.
I will address that with an ib_client; SunRPC patches forthcoming.

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 56e568fcd32b..c9a2bdb49e3c 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -694,6 +694,9 @@ cma_validate_port(struct ib_device *device, u32 port,
   	if (!rdma_dev_access_netns(device, id_priv->id.route.addr.dev_addr.net))
   		return ERR_PTR(-ENODEV);
+	if (rdma_protocol_iwarp(device, port))
+		return rdma_get_gid_attr(device, port, 0);

This might work, but I'm skeptical of the conditional. There's nothing
special about iWARP that says a GID should come from the outgoing device
mac. And, other protocols without IB GID addressing won't benefit.

The GID represents the source address, so it better come from the
outgoing device or something is really wrong.

iWARP gets a conditional because iwarp always has a single GID, other
devices do not work that way.


Thanks. If I get this problem correctly, this problem is about "GID can not be generated correctly if a iWARP device is attached to a loopback device". This patch will fix this problem. So iWARP device can be managed via this unique GID.

Do you mean that RXE does not have the similar problem?
But if a RXE device is attached to a loopback device, the similar problem occurs.

Zhu Yanjun


Jason




[Index of Archives]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Photo]     [Yosemite News]     [Yosemite Photos]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux