On 6/23/2023 2:40 PM, Chuck Lever III wrote:
On Jun 23, 2023, at 2:37 PM, Tom Talpey <tom@xxxxxxxxxx> wrote:
On 6/14/2023 10:00 AM, Chuck Lever wrote:
From: Chuck Lever <chuck.lever@xxxxxxxxxx>
Have the iwarp side properly set the ndev in the device's sgid_attrs
so that address resolution can treat it more like a RoCE device.
Suggested-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
drivers/infiniband/core/cache.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/infiniband/core/cache.c b/drivers/infiniband/core/cache.c
index 2e91d8879326..717524fe8a39 100644
--- a/drivers/infiniband/core/cache.c
+++ b/drivers/infiniband/core/cache.c
@@ -1439,6 +1439,7 @@ static int config_non_roce_gid_cache(struct ib_device *device,
{
struct ib_gid_attr gid_attr = {};
struct ib_gid_table *table;
+ struct net_device *ndev;
int ret = 0;
int i;
@@ -1457,10 +1458,21 @@ static int config_non_roce_gid_cache(struct ib_device *device,
i);
goto err;
}
+
+ ndev = NULL;
+ if (rdma_protocol_iwarp(device, port)) {
+ ndev = ib_device_get_netdev(device, port);
+ if (!ndev)
+ continue;
+ RCU_INIT_POINTER(gid_attr.ndev, ndev);
+ }
+
gid_attr.index = i;
tprops->subnet_prefix =
be64_to_cpu(gid_attr.gid.global.subnet_prefix);
add_modify_gid(table, &gid_attr);
+
+ dev_put(ndev);
I'm not sure about two things here...
1) is it correct to dev_put(ndev) when returning? It seems that this
may risk the device may vanish when it's still present in the cache.
Feel free to tell me I'm confused.
ib_device_get_netdev() increments the ndev's reference count
before returning. dev_put() releases that reference.
2) Assuming yes, shouldn't the dev_put(ndev) move to within the new
if(iwarp) block just above?
If the "if (iwarp)" block isn't taken, then ndev is NULL and that
makes the dev_put() a no-op.
I still think it would be clearer and less side-effect sensitive to
put the call inside the if(iwarp) block.
Thanks for the dev_put clarification.
Reviewed-by: Tom Talpey <tom@xxxxxxxxxx>
Tom.
}
err:
mutex_unlock(&table->lock);
--
Chuck Lever
