Merge branch 'net-smc-add-support-for-generic-netlink-api'

Karsten Graul says:

====================
net/smc: Add support for generic netlink API

Up to version 4 this patch series was using the sock_diag netlink
infrastructure. This version is using the generic netlink API. Generic
netlink API offers a better type safety between kernel and userspace
communication.
Using the generic netlink API the smc module can now provide information
about SMC linkgroups, links and devices (both for SMC-R and SMC-D).

v2: Add missing include to uapi header smc_diag.h.

v3: Apply code style recommendations from review comments.
    Instead of using EXPORTs to allow the smc_diag module to access
    data of the smc module, introduce struct smc_diag_ops and let
    smc_diag access the required data using function pointers.

v4: Address checkpatch.pl warnings. Do not use static inline for
    functions.

v5: Use generic netlink API instead of the sock_diag netlink
    infrastructure.

v6: Integrate more review comments from Jakub.

v7: Use nla_nest_start() with the new family. Use .maxattr=1 in the
    genl family and define one entry for attribute 1 in the policy to
    reject this attritbute for all commands. All other possible attributes
    are rejected because NL_VALIDATE_STRICT is set for the policy
    implicitely, which includes NL_VALIDATE_MAXTYPE.
    Setting policy[0].strict_start_type=1 does not work here because there
    is no valid attribute defined for this family, only plain commands. For
    any type > maxtype (which is .maxattr) validate_nla() would return 0 to
    userspace instead of -EINVAL. What helps here is __nla_validate_parse()
    which checks for type > maxtype and returns -EINVAL when NL_VALIDATE_MAXTYPE
    is set. This requires the one entry for type == .maxattr with
    .type = NLA_REJECT in the nla_policy.
    When a future command wants to allow attributes then it can easily specify a
    dedicated .policy for this new command in the genl_ops array. This dedicated
    policy overlays the global policy specified in the genl_family structure.
====================

Link: https://lore.kernel.org/r/20201201192049.53517-1-kgraul@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 126 insertions, 0 deletions

diff --git a/include/uapi/linux/smc.h b/include/uapi/linux/smc.h
index 0e11ca421ca4..3e68da07fba2 100644
--- a/include/uapi/linux/smc.h
+++ b/include/uapi/linux/smc.h
@@ -33,4 +33,130 @@ enum {				/* SMC PNET Table commands */
 #define SMCR_GENL_FAMILY_NAME		"SMC_PNETID"
 #define SMCR_GENL_FAMILY_VERSION	1
 
+/* gennetlink interface to access non-socket information from SMC module */
+#define SMC_GENL_FAMILY_NAME		"SMC_GEN_NETLINK"
+#define SMC_GENL_FAMILY_VERSION		1
+
+#define SMC_PCI_ID_STR_LEN		16 /* Max length of pci id string */
+
+/* SMC_GENL_FAMILY commands */
+enum {
+	SMC_NETLINK_GET_SYS_INFO = 1,
+	SMC_NETLINK_GET_LGR_SMCR,
+	SMC_NETLINK_GET_LINK_SMCR,
+	SMC_NETLINK_GET_LGR_SMCD,
+	SMC_NETLINK_GET_DEV_SMCD,
+	SMC_NETLINK_GET_DEV_SMCR,
+};
+
+/* SMC_GENL_FAMILY top level attributes */
+enum {
+	SMC_GEN_UNSPEC,
+	SMC_GEN_SYS_INFO,		/* nest */
+	SMC_GEN_LGR_SMCR,		/* nest */
+	SMC_GEN_LINK_SMCR,		/* nest */
+	SMC_GEN_LGR_SMCD,		/* nest */
+	SMC_GEN_DEV_SMCD,		/* nest */
+	SMC_GEN_DEV_SMCR,		/* nest */
+	__SMC_GEN_MAX,
+	SMC_GEN_MAX = __SMC_GEN_MAX - 1
+};
+
+/* SMC_GEN_SYS_INFO attributes */
+enum {
+	SMC_NLA_SYS_UNSPEC,
+	SMC_NLA_SYS_VER,		/* u8 */
+	SMC_NLA_SYS_REL,		/* u8 */
+	SMC_NLA_SYS_IS_ISM_V2,		/* u8 */
+	SMC_NLA_SYS_LOCAL_HOST,		/* string */
+	SMC_NLA_SYS_SEID,		/* string */
+	__SMC_NLA_SYS_MAX,
+	SMC_NLA_SYS_MAX = __SMC_NLA_SYS_MAX - 1
+};
+
+/* SMC_NLA_LGR_V2 nested attributes */
+enum {
+	SMC_NLA_LGR_V2_VER,		/* u8 */
+	SMC_NLA_LGR_V2_REL,		/* u8 */
+	SMC_NLA_LGR_V2_OS,		/* u8 */
+	SMC_NLA_LGR_V2_NEG_EID,		/* string */
+	SMC_NLA_LGR_V2_PEER_HOST,	/* string */
+};
+
+/* SMC_GEN_LGR_SMCR attributes */
+enum {
+	SMC_NLA_LGR_R_UNSPEC,
+	SMC_NLA_LGR_R_ID,		/* u32 */
+	SMC_NLA_LGR_R_ROLE,		/* u8 */
+	SMC_NLA_LGR_R_TYPE,		/* u8 */
+	SMC_NLA_LGR_R_PNETID,		/* string */
+	SMC_NLA_LGR_R_VLAN_ID,		/* u8 */
+	SMC_NLA_LGR_R_CONNS_NUM,	/* u32 */
+	__SMC_NLA_LGR_R_MAX,
+	SMC_NLA_LGR_R_MAX = __SMC_NLA_LGR_R_MAX - 1
+};
+
+/* SMC_GEN_LINK_SMCR attributes */
+enum {
+	SMC_NLA_LINK_UNSPEC,
+	SMC_NLA_LINK_ID,		/* u8 */
+	SMC_NLA_LINK_IB_DEV,		/* string */
+	SMC_NLA_LINK_IB_PORT,		/* u8 */
+	SMC_NLA_LINK_GID,		/* string */
+	SMC_NLA_LINK_PEER_GID,		/* string */
+	SMC_NLA_LINK_CONN_CNT,		/* u32 */
+	SMC_NLA_LINK_NET_DEV,		/* u32 */
+	SMC_NLA_LINK_UID,		/* u32 */
+	SMC_NLA_LINK_PEER_UID,		/* u32 */
+	SMC_NLA_LINK_STATE,		/* u32 */
+	__SMC_NLA_LINK_MAX,
+	SMC_NLA_LINK_MAX = __SMC_NLA_LINK_MAX - 1
+};
+
+/* SMC_GEN_LGR_SMCD attributes */
+enum {
+	SMC_NLA_LGR_D_UNSPEC,
+	SMC_NLA_LGR_D_ID,		/* u32 */
+	SMC_NLA_LGR_D_GID,		/* u64 */
+	SMC_NLA_LGR_D_PEER_GID,		/* u64 */
+	SMC_NLA_LGR_D_VLAN_ID,		/* u8 */
+	SMC_NLA_LGR_D_CONNS_NUM,	/* u32 */
+	SMC_NLA_LGR_D_PNETID,		/* string */
+	SMC_NLA_LGR_D_CHID,		/* u16 */
+	SMC_NLA_LGR_D_PAD,		/* flag */
+	SMC_NLA_LGR_V2,			/* nest */
+	__SMC_NLA_LGR_D_MAX,
+	SMC_NLA_LGR_D_MAX = __SMC_NLA_LGR_D_MAX - 1
+};
+
+/* SMC_NLA_DEV_PORT nested attributes */
+enum {
+	SMC_NLA_DEV_PORT_UNSPEC,
+	SMC_NLA_DEV_PORT_PNET_USR,	/* u8 */
+	SMC_NLA_DEV_PORT_PNETID,	/* string */
+	SMC_NLA_DEV_PORT_NETDEV,	/* u32 */
+	SMC_NLA_DEV_PORT_STATE,		/* u8 */
+	SMC_NLA_DEV_PORT_VALID,		/* u8 */
+	SMC_NLA_DEV_PORT_LNK_CNT,	/* u32 */
+	__SMC_NLA_DEV_PORT_MAX,
+	SMC_NLA_DEV_PORT_MAX = __SMC_NLA_DEV_PORT_MAX - 1
+};
+
+/* SMC_GEN_DEV_SMCD and SMC_GEN_DEV_SMCR attributes */
+enum {
+	SMC_NLA_DEV_UNSPEC,
+	SMC_NLA_DEV_USE_CNT,		/* u32 */
+	SMC_NLA_DEV_IS_CRIT,		/* u8 */
+	SMC_NLA_DEV_PCI_FID,		/* u32 */
+	SMC_NLA_DEV_PCI_CHID,		/* u16 */
+	SMC_NLA_DEV_PCI_VENDOR,		/* u16 */
+	SMC_NLA_DEV_PCI_DEVICE,		/* u16 */
+	SMC_NLA_DEV_PCI_ID,		/* string */
+	SMC_NLA_DEV_PORT,		/* nest */
+	SMC_NLA_DEV_PORT2,		/* nest */
+	SMC_NLA_DEV_IB_NAME,		/* string */
+	__SMC_NLA_DEV_MAX,
+	SMC_NLA_DEV_MAX = __SMC_NLA_DEV_MAX - 1
+};
+
 #endif /* _UAPI_LINUX_SMC_H */