On Tue, Dec 28, 2021 at 09:06:10PM +0800, Tony Lu wrote:
> This adds net namespace ID to diag of linkgroup, helps us to distinguish
> different namespaces, and net_cookie is unique in the whole system.
>
> Signed-off-by: Tony Lu <tonylu@xxxxxxxxxxxxxxxxx>
> ---
> include/uapi/linux/smc.h | 2 ++
> include/uapi/linux/smc_diag.h | 11 ++++++-----
> net/smc/smc_core.c | 3 +++
> net/smc/smc_diag.c | 16 +++++++++-------
> 4 files changed, 20 insertions(+), 12 deletions(-)
>
> diff --git a/include/uapi/linux/smc.h b/include/uapi/linux/smc.h
> index 20f33b27787f..6c2874fd2c00 100644
> --- a/include/uapi/linux/smc.h
> +++ b/include/uapi/linux/smc.h
> @@ -119,6 +119,8 @@ enum {
> SMC_NLA_LGR_R_CONNS_NUM, /* u32 */
> SMC_NLA_LGR_R_V2_COMMON, /* nest */
> SMC_NLA_LGR_R_V2, /* nest */
> + SMC_NLA_LGR_R_NET_COOKIE, /* u64 */
> + SMC_NLA_LGR_R_PAD, /* flag */
> __SMC_NLA_LGR_R_MAX,
> SMC_NLA_LGR_R_MAX = __SMC_NLA_LGR_R_MAX - 1
> };
> diff --git a/include/uapi/linux/smc_diag.h b/include/uapi/linux/smc_diag.h
> index 8cb3a6fef553..c7008d87f1a4 100644
> --- a/include/uapi/linux/smc_diag.h
> +++ b/include/uapi/linux/smc_diag.h
> @@ -84,11 +84,12 @@ struct smc_diag_conninfo {
> /* SMC_DIAG_LINKINFO */
>
> struct smc_diag_linkinfo {
> - __u8 link_id; /* link identifier */
> - __u8 ibname[IB_DEVICE_NAME_MAX]; /* name of the RDMA device */
> - __u8 ibport; /* RDMA device port number */
> - __u8 gid[40]; /* local GID */
> - __u8 peer_gid[40]; /* peer GID */
> + __u8 link_id; /* link identifier */
> + __u8 ibname[IB_DEVICE_NAME_MAX]; /* name of the RDMA device */
> + __u8 ibport; /* RDMA device port number */
> + __u8 gid[40]; /* local GID */
> + __u8 peer_gid[40]; /* peer GID */
> + __aligned_u64 net_cookie; /* RDMA device net namespace */
> };
>
> struct smc_diag_lgrinfo {
I'm sorry but this is an ABI regression.
Since struct smc_diag_lgrinfo contains an object of type "struct smc_diag_linkinfo",
offset of all subsequent members of struct smc_diag_lgrinfo is changed by
this patch.
As result, applications compiled with the old version of struct smc_diag_linkinfo
will receive garbage in struct smc_diag_lgrinfo.role if the kernel implements
this new version of struct smc_diag_linkinfo.
--
ldv
