From 36c5100e859d93b3436ae24810612b05addb1e89 Mon Sep 17 00:00:00 2001 From: Amit Cohen Date: Sun, 7 Feb 2021 10:22:50 +0200 Subject: IPv4: Add "offload failed" indication to routes After installing a route to the kernel, user space receives an acknowledgment, which means the route was installed in the kernel, but not necessarily in hardware. The asynchronous nature of route installation in hardware can lead to a routing daemon advertising a route before it was actually installed in hardware. This can result in packet loss or mis-routed packets until the route is installed in hardware. To avoid such cases, previous patch set added the ability to emit RTM_NEWROUTE notifications whenever RTM_F_OFFLOAD/RTM_F_TRAP flags are changed, this behavior is controlled by sysctl. With the above mentioned behavior, it is possible to know from user-space if the route was offloaded, but if the offload fails there is no indication to user-space. Following a failure, a routing daemon will wait indefinitely for a notification that will never come. This patch adds an "offload_failed" indication to IPv4 routes, so that users will have better visibility into the offload process. 'struct fib_alias', and 'struct fib_rt_info' are extended with new field that indicates if route offload failed. Note that the new field is added using unused bit and therefore there is no need to increase structs size. Signed-off-by: Amit Cohen Signed-off-by: Ido Schimmel Signed-off-by: David S. Miller --- include/net/ip_fib.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index 2ec062aaa978..a914f33f3ed5 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -213,7 +213,8 @@ struct fib_rt_info { u8 type; u8 offload:1, trap:1, - unused:6; + offload_failed:1, + unused:5; }; struct fib_entry_notifier_info { -- cgit v1.2.3