The ghost sndbuf descriptor will be created and attached to peer DMB
once peer token is obtained and it will be detach and freed when the
connection is freed.
Signed-off-by: Wen Gu <guwen@xxxxxxxxxxxxxxxxx>
---
net/smc/af_smc.c | 21 ++++++++++++++++
net/smc/smc_core.c | 71 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
net/smc/smc_core.h | 1 +
3 files changed, 92 insertions(+), 1 deletion(-)
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 6c0e381..838cf9c 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -1449,6 +1449,14 @@ static int smc_connect_ism(struct smc_sock *smc,
}
smc_conn_save_peer_info(smc, aclc);
+
+ if (smc_ism_dmb_mappable(smc->conn.lgr->smcd)) {
+ rc = smcd_buf_attach(smc);
+ if (rc) {
+ rc = SMC_CLC_DECL_MEM; /* try to fallback */
+ goto connect_abort;
+ }
+ }
smc_close_init(smc);
smc_rx_init(smc);
smc_tx_init(smc);
@@ -2559,6 +2567,19 @@ static void smc_listen_work(struct work_struct *work)
mutex_unlock(&smc_server_lgr_pending);
}
smc_conn_save_peer_info(new_smc, cclc);
+
+ if (ini->is_smcd &&
+ smc_ism_dmb_mappable(new_smc->conn.lgr->smcd)) {
+ rc = smcd_buf_attach(new_smc);
+ if (rc)
+ /* SMC-D client has completed the CLC process,
+ * so server can not send decline any more.
+ * This requires the rc returned here no larger
+ * than 0.
+ */
+ goto out_decl;
+ }
+
smc_listen_out_connected(new_smc);
SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
goto out_free;
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 95cc954..4a76e38 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -1149,6 +1149,20 @@ static void smcr_buf_unuse(struct smc_buf_desc *buf_desc, bool is_rmb,
}
}
+static void smcd_buf_detach(struct smc_connection *conn)
+{
+ struct smcd_dev *smcd = conn->lgr->smcd;
+ u64 peer_token = conn->peer_token;
+
+ if (!conn->sndbuf_desc)
+ return;
+
+ smc_ism_detach_dmb(smcd, peer_token);
+
+ kfree(conn->sndbuf_desc);
+ conn->sndbuf_desc = NULL;
+}
+
static void smc_buf_unuse(struct smc_connection *conn,
struct smc_link_group *lgr)
{
@@ -1192,6 +1206,8 @@ void smc_conn_free(struct smc_connection *conn)
if (lgr->is_smcd) {
if (!list_empty(&lgr->list))
smc_ism_unset_conn(conn);
+ if (smc_ism_dmb_mappable(lgr->smcd))
+ smcd_buf_detach(conn);
tasklet_kill(&conn->rx_tsklet);
} else {
smc_cdc_wait_pend_tx_wr(conn);
@@ -1445,6 +1461,8 @@ static void smc_conn_kill(struct smc_connection *conn, bool soft)
smc_sk_wake_ups(smc);
if (conn->lgr->is_smcd) {
smc_ism_unset_conn(conn);
+ if (smc_ism_dmb_mappable(conn->lgr->smcd))
+ smcd_buf_detach(conn);
if (soft)
tasklet_kill(&conn->rx_tsklet);
else
@@ -2455,15 +2473,23 @@ void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
*/
int smc_buf_create(struct smc_sock *smc, bool is_smcd)
{
+ bool sndbuf_created = false;
int rc;
/* create send buffer */
+ if (is_smcd &&
+ smc_ism_dmb_mappable(smc->conn.lgr->smcd))
+ goto create_rmb;
+
rc = __smc_buf_create(smc, is_smcd, false);
if (rc)
return rc;
+ sndbuf_created = true;
+
+create_rmb:
/* create rmb */
rc = __smc_buf_create(smc, is_smcd, true);
- if (rc) {
+ if (rc && sndbuf_created) {
down_write(&smc->conn.lgr->sndbufs_lock);
list_del(&smc->conn.sndbuf_desc->list);
up_write(&smc->conn.lgr->sndbufs_lock);
@@ -2473,6 +2499,49 @@ int smc_buf_create(struct smc_sock *smc, bool is_smcd)
return rc;
}
+int smcd_buf_attach(struct smc_sock *smc)
+{
+ struct smc_connection *conn = &smc->conn;
+ struct smcd_dev *smcd = conn->lgr->smcd;
+ u64 peer_token = conn->peer_token;
+ struct smc_buf_desc *buf_desc;
+ int rc;
+
+ buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
+ if (!buf_desc)
+ return -ENOMEM;
+
+ /* The ghost sndbuf_desc describes the same memory region as
+ * peer RMB. Its lifecycle is consistent with the connection's
+ * and it will be freed with the connections instead of the
+ * link group.
+ */
+ rc = smc_ism_attach_dmb(smcd, peer_token, buf_desc);
+ if (rc)
+ goto free;
+
+ smc->sk.sk_sndbuf = buf_desc->len;
+ buf_desc->cpu_addr =
+ (u8 *)buf_desc->cpu_addr + sizeof(struct smcd_cdc_msg);
+ buf_desc->len -= sizeof(struct smcd_cdc_msg);
+ conn->sndbuf_desc = buf_desc;
+ conn->sndbuf_desc->used = 1;
+ atomic_set(&conn->sndbuf_space, conn->sndbuf_desc->len);
+ return 0;
+
+free:
+ if (conn->rmb_desc) {
+ /* free local RMB as well */
+ down_write(&conn->lgr->rmbs_lock);
+ list_del(&conn->rmb_desc->list);
+ up_write(&conn->lgr->rmbs_lock);
+ smc_buf_free(conn->lgr, true, conn->rmb_desc);
+ conn->rmb_desc = NULL;
+ }
+ kfree(buf_desc);
+ return rc;
+}
+
static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
{
int i;
diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 1f17537..d93cf51 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -557,6 +557,7 @@ void smc_smcd_terminate(struct smcd_dev *dev, struct smcd_gid *peer_gid,
void smc_smcd_terminate_all(struct smcd_dev *dev);
void smc_smcr_terminate_all(struct smc_ib_device *smcibdev);
int smc_buf_create(struct smc_sock *smc, bool is_smcd);
+int smcd_buf_attach(struct smc_sock *smc);
int smc_uncompress_bufsize(u8 compressed);
int smc_rmb_rtoken_handling(struct smc_connection *conn, struct smc_link *link,
struct smc_clc_msg_accept_confirm *clc);
--
1.8.3.1
