[RFC PATCH net-next v4 03/11] net/smc: implement ID-related operations of loopback-ism

Wen Gu
2024-03-17T10:06:02Z

This implements GID and CHID related operations of loopback-ism device.
loopback-ism acts as an ISMv2. It's GID is generated randomly by UUIDv4
algorithm and CHID is reserved 0xFFFF.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
---
net/smc/smc_loopback.c | 62 ++++++++++++++++++++++++++++++++++++++----
net/smc/smc_loopback.h | 3 ++
2 files changed, 60 insertions(+), 5 deletions(-)

diff --git a/net/smc/smc_loopback.c b/net/smc/smc_loopback.c
index e9170d86e58f..7656a2474500 100644
--- a/net/smc/smc_loopback.c
+++ b/net/smc/smc_loopback.c
@@ -19,11 +19,62 @@
#include "smc_loopback.h"

#if IS_ENABLED(CONFIG_SMC_LO)
+#define SMC_LO_V2_CAPABLE 0x1 /* loopback-ism acts as ISMv2 */
+
static const char smc_lo_dev_name[] = "loopback-ism";
static struct smc_lo_dev *lo_dev;

+static void smc_lo_generate_id(struct smc_lo_dev *ldev)
+{
+ struct smcd_gid *lgid = &ldev->local_gid;
+ uuid_t uuid;
+
+ uuid_gen(&uuid);
+ memcpy(&lgid->gid, &uuid, sizeof(lgid->gid));
+ memcpy(&lgid->gid_ext, (u8 *)&uuid + sizeof(lgid->gid),
+ sizeof(lgid->gid_ext));
+
+ ldev->chid = SMC_LO_CHID;
+}
+
+static int smc_lo_query_rgid(struct smcd_dev *smcd, struct smcd_gid *rgid,
+ u32 vid_valid, u32 vid)
+{
+ struct smc_lo_dev *ldev = smcd->priv;
+
+ /* rgid should be the same as lgid */
+ if (!ldev || rgid->gid != ldev->local_gid.gid ||
+ rgid->gid_ext != ldev->local_gid.gid_ext)
+ return -ENETUNREACH;
+ return 0;
+}
+
+static int smc_lo_supports_v2(void)
+{
+ return SMC_LO_V2_CAPABLE;
+}
+
+static void smc_lo_get_local_gid(struct smcd_dev *smcd,
+ struct smcd_gid *smcd_gid)
+{
+ struct smc_lo_dev *ldev = smcd->priv;
+
+ smcd_gid->gid = ldev->local_gid.gid;
+ smcd_gid->gid_ext = ldev->local_gid.gid_ext;
+}
+
+static u16 smc_lo_get_chid(struct smcd_dev *smcd)
+{
+ return ((struct smc_lo_dev *)smcd->priv)->chid;
+}
+
+static struct device *smc_lo_get_dev(struct smcd_dev *smcd)
+{
+ return &((struct smc_lo_dev *)smcd->priv)->dev;
+}
+
static const struct smcd_ops lo_ops = {
- .query_remote_gid = NULL,
+ .query_remote_gid = smc_lo_query_rgid,
.register_dmb = NULL,
.unregister_dmb = NULL,
.add_vlan_id = NULL,
@@ -32,10 +83,10 @@ static const struct smcd_ops lo_ops = {
.reset_vlan_required = NULL,
.signal_event = NULL,
.move_data = NULL,
- .supports_v2 = NULL,
- .get_local_gid = NULL,
- .get_chid = NULL,
- .get_dev = NULL,
+ .supports_v2 = smc_lo_supports_v2,
+ .get_local_gid = smc_lo_get_local_gid,
+ .get_chid = smc_lo_get_chid,
+ .get_dev = smc_lo_get_dev,
};

static struct smcd_dev *smcd_lo_alloc_dev(const struct smcd_ops *ops,
@@ -95,6 +146,7 @@ static void smcd_lo_unregister_dev(struct smc_lo_dev *ldev)

static int smc_lo_dev_init(struct smc_lo_dev *ldev)
{
+ smc_lo_generate_id(ldev);
return smcd_lo_register_dev(ldev);
}

diff --git a/net/smc/smc_loopback.h b/net/smc/smc_loopback.h
index 9dd44d4c0ca3..55b41133a97f 100644
--- a/net/smc/smc_loopback.h
+++ b/net/smc/smc_loopback.h
@@ -20,10 +20,13 @@

#if IS_ENABLED(CONFIG_SMC_LO)
#define SMC_LO_MAX_DMBS 5000
+#define SMC_LO_CHID 0xFFFF

struct smc_lo_dev {
struct smcd_dev *smcd;
struct device dev;
+ u16 chid;
+ struct smcd_gid local_gid;
};
#endif

--
2.32.0.3.g01195cf9f