diff options
Diffstat (limited to 'net/smc/smc_core.c')
-rw-r--r-- | net/smc/smc_core.c | 2633 |
1 files changed, 2633 insertions, 0 deletions
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c new file mode 100644 index 0000000000..d520ee62c8 --- /dev/null +++ b/net/smc/smc_core.c @@ -0,0 +1,2633 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * Basic Transport Functions exploiting Infiniband API + * + * Copyright IBM Corp. 2016 + * + * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com> + */ + +#include <linux/socket.h> +#include <linux/if_vlan.h> +#include <linux/random.h> +#include <linux/workqueue.h> +#include <linux/wait.h> +#include <linux/reboot.h> +#include <linux/mutex.h> +#include <linux/list.h> +#include <linux/smc.h> +#include <net/tcp.h> +#include <net/sock.h> +#include <rdma/ib_verbs.h> +#include <rdma/ib_cache.h> + +#include "smc.h" +#include "smc_clc.h" +#include "smc_core.h" +#include "smc_ib.h" +#include "smc_wr.h" +#include "smc_llc.h" +#include "smc_cdc.h" +#include "smc_close.h" +#include "smc_ism.h" +#include "smc_netlink.h" +#include "smc_stats.h" +#include "smc_tracepoint.h" + +#define SMC_LGR_NUM_INCR 256 +#define SMC_LGR_FREE_DELAY_SERV (600 * HZ) +#define SMC_LGR_FREE_DELAY_CLNT (SMC_LGR_FREE_DELAY_SERV + 10 * HZ) + +struct smc_lgr_list smc_lgr_list = { /* established link groups */ + .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock), + .list = LIST_HEAD_INIT(smc_lgr_list.list), + .num = 0, +}; + +static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */ +static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted); + +static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb, + struct smc_buf_desc *buf_desc); +static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft); + +static void smc_link_down_work(struct work_struct *work); + +/* return head of link group list and its lock for a given link group */ +static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr, + spinlock_t **lgr_lock) +{ + if (lgr->is_smcd) { + *lgr_lock = &lgr->smcd->lgr_lock; + return &lgr->smcd->lgr_list; + } + + *lgr_lock = &smc_lgr_list.lock; + return &smc_lgr_list.list; +} + +static void smc_ibdev_cnt_inc(struct smc_link *lnk) +{ + atomic_inc(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]); +} + +static void smc_ibdev_cnt_dec(struct smc_link *lnk) +{ + atomic_dec(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]); +} + +static void smc_lgr_schedule_free_work(struct smc_link_group *lgr) +{ + /* client link group creation always follows the server link group + * creation. For client use a somewhat higher removal delay time, + * otherwise there is a risk of out-of-sync link groups. + */ + if (!lgr->freeing) { + mod_delayed_work(system_wq, &lgr->free_work, + (!lgr->is_smcd && lgr->role == SMC_CLNT) ? + SMC_LGR_FREE_DELAY_CLNT : + SMC_LGR_FREE_DELAY_SERV); + } +} + +/* Register connection's alert token in our lookup structure. + * To use rbtrees we have to implement our own insert core. + * Requires @conns_lock + * @smc connection to register + * Returns 0 on success, != otherwise. + */ +static void smc_lgr_add_alert_token(struct smc_connection *conn) +{ + struct rb_node **link, *parent = NULL; + u32 token = conn->alert_token_local; + + link = &conn->lgr->conns_all.rb_node; + while (*link) { + struct smc_connection *cur = rb_entry(*link, + struct smc_connection, alert_node); + + parent = *link; + if (cur->alert_token_local > token) + link = &parent->rb_left; + else + link = &parent->rb_right; + } + /* Put the new node there */ + rb_link_node(&conn->alert_node, parent, link); + rb_insert_color(&conn->alert_node, &conn->lgr->conns_all); +} + +/* assign an SMC-R link to the connection */ +static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first) +{ + enum smc_link_state expected = first ? SMC_LNK_ACTIVATING : + SMC_LNK_ACTIVE; + int i, j; + + /* do link balancing */ + conn->lnk = NULL; /* reset conn->lnk first */ + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + struct smc_link *lnk = &conn->lgr->lnk[i]; + + if (lnk->state != expected || lnk->link_is_asym) + continue; + if (conn->lgr->role == SMC_CLNT) { + conn->lnk = lnk; /* temporary, SMC server assigns link*/ + break; + } + if (conn->lgr->conns_num % 2) { + for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) { + struct smc_link *lnk2; + + lnk2 = &conn->lgr->lnk[j]; + if (lnk2->state == expected && + !lnk2->link_is_asym) { + conn->lnk = lnk2; + break; + } + } + } + if (!conn->lnk) + conn->lnk = lnk; + break; + } + if (!conn->lnk) + return SMC_CLC_DECL_NOACTLINK; + atomic_inc(&conn->lnk->conn_cnt); + return 0; +} + +/* Register connection in link group by assigning an alert token + * registered in a search tree. + * Requires @conns_lock + * Note that '0' is a reserved value and not assigned. + */ +static int smc_lgr_register_conn(struct smc_connection *conn, bool first) +{ + struct smc_sock *smc = container_of(conn, struct smc_sock, conn); + static atomic_t nexttoken = ATOMIC_INIT(0); + int rc; + + if (!conn->lgr->is_smcd) { + rc = smcr_lgr_conn_assign_link(conn, first); + if (rc) { + conn->lgr = NULL; + return rc; + } + } + /* find a new alert_token_local value not yet used by some connection + * in this link group + */ + sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */ + while (!conn->alert_token_local) { + conn->alert_token_local = atomic_inc_return(&nexttoken); + if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr)) + conn->alert_token_local = 0; + } + smc_lgr_add_alert_token(conn); + conn->lgr->conns_num++; + return 0; +} + +/* Unregister connection and reset the alert token of the given connection< + */ +static void __smc_lgr_unregister_conn(struct smc_connection *conn) +{ + struct smc_sock *smc = container_of(conn, struct smc_sock, conn); + struct smc_link_group *lgr = conn->lgr; + + rb_erase(&conn->alert_node, &lgr->conns_all); + if (conn->lnk) + atomic_dec(&conn->lnk->conn_cnt); + lgr->conns_num--; + conn->alert_token_local = 0; + sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */ +} + +/* Unregister connection from lgr + */ +static void smc_lgr_unregister_conn(struct smc_connection *conn) +{ + struct smc_link_group *lgr = conn->lgr; + + if (!smc_conn_lgr_valid(conn)) + return; + write_lock_bh(&lgr->conns_lock); + if (conn->alert_token_local) { + __smc_lgr_unregister_conn(conn); + } + write_unlock_bh(&lgr->conns_lock); +} + +int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb); + char hostname[SMC_MAX_HOSTNAME_LEN + 1]; + char smc_seid[SMC_MAX_EID_LEN + 1]; + struct nlattr *attrs; + u8 *seid = NULL; + u8 *host = NULL; + void *nlh; + + nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + &smc_gen_nl_family, NLM_F_MULTI, + SMC_NETLINK_GET_SYS_INFO); + if (!nlh) + goto errmsg; + if (cb_ctx->pos[0]) + goto errout; + attrs = nla_nest_start(skb, SMC_GEN_SYS_INFO); + if (!attrs) + goto errout; + if (nla_put_u8(skb, SMC_NLA_SYS_VER, SMC_V2)) + goto errattr; + if (nla_put_u8(skb, SMC_NLA_SYS_REL, SMC_RELEASE)) + goto errattr; + if (nla_put_u8(skb, SMC_NLA_SYS_IS_ISM_V2, smc_ism_is_v2_capable())) + goto errattr; + if (nla_put_u8(skb, SMC_NLA_SYS_IS_SMCR_V2, true)) + goto errattr; + smc_clc_get_hostname(&host); + if (host) { + memcpy(hostname, host, SMC_MAX_HOSTNAME_LEN); + hostname[SMC_MAX_HOSTNAME_LEN] = 0; + if (nla_put_string(skb, SMC_NLA_SYS_LOCAL_HOST, hostname)) + goto errattr; + } + if (smc_ism_is_v2_capable()) { + smc_ism_get_system_eid(&seid); + memcpy(smc_seid, seid, SMC_MAX_EID_LEN); + smc_seid[SMC_MAX_EID_LEN] = 0; + if (nla_put_string(skb, SMC_NLA_SYS_SEID, smc_seid)) + goto errattr; + } + nla_nest_end(skb, attrs); + genlmsg_end(skb, nlh); + cb_ctx->pos[0] = 1; + return skb->len; + +errattr: + nla_nest_cancel(skb, attrs); +errout: + genlmsg_cancel(skb, nlh); +errmsg: + return skb->len; +} + +/* Fill SMC_NLA_LGR_D_V2_COMMON/SMC_NLA_LGR_R_V2_COMMON nested attributes */ +static int smc_nl_fill_lgr_v2_common(struct smc_link_group *lgr, + struct sk_buff *skb, + struct netlink_callback *cb, + struct nlattr *v2_attrs) +{ + char smc_host[SMC_MAX_HOSTNAME_LEN + 1]; + char smc_eid[SMC_MAX_EID_LEN + 1]; + + if (nla_put_u8(skb, SMC_NLA_LGR_V2_VER, lgr->smc_version)) + goto errv2attr; + if (nla_put_u8(skb, SMC_NLA_LGR_V2_REL, lgr->peer_smc_release)) + goto errv2attr; + if (nla_put_u8(skb, SMC_NLA_LGR_V2_OS, lgr->peer_os)) + goto errv2attr; + memcpy(smc_host, lgr->peer_hostname, SMC_MAX_HOSTNAME_LEN); + smc_host[SMC_MAX_HOSTNAME_LEN] = 0; + if (nla_put_string(skb, SMC_NLA_LGR_V2_PEER_HOST, smc_host)) + goto errv2attr; + memcpy(smc_eid, lgr->negotiated_eid, SMC_MAX_EID_LEN); + smc_eid[SMC_MAX_EID_LEN] = 0; + if (nla_put_string(skb, SMC_NLA_LGR_V2_NEG_EID, smc_eid)) + goto errv2attr; + + nla_nest_end(skb, v2_attrs); + return 0; + +errv2attr: + nla_nest_cancel(skb, v2_attrs); + return -EMSGSIZE; +} + +static int smc_nl_fill_smcr_lgr_v2(struct smc_link_group *lgr, + struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct nlattr *v2_attrs; + + v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2); + if (!v2_attrs) + goto errattr; + if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_DIRECT, !lgr->uses_gateway)) + goto errv2attr; + if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_MAX_CONNS, lgr->max_conns)) + goto errv2attr; + if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_MAX_LINKS, lgr->max_links)) + goto errv2attr; + + nla_nest_end(skb, v2_attrs); + return 0; + +errv2attr: + nla_nest_cancel(skb, v2_attrs); +errattr: + return -EMSGSIZE; +} + +static int smc_nl_fill_lgr(struct smc_link_group *lgr, + struct sk_buff *skb, + struct netlink_callback *cb) +{ + char smc_target[SMC_MAX_PNETID_LEN + 1]; + struct nlattr *attrs, *v2_attrs; + + attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCR); + if (!attrs) + goto errout; + + if (nla_put_u32(skb, SMC_NLA_LGR_R_ID, *((u32 *)&lgr->id))) + goto errattr; + if (nla_put_u32(skb, SMC_NLA_LGR_R_CONNS_NUM, lgr->conns_num)) + goto errattr; + if (nla_put_u8(skb, SMC_NLA_LGR_R_ROLE, lgr->role)) + goto errattr; + if (nla_put_u8(skb, SMC_NLA_LGR_R_TYPE, lgr->type)) + goto errattr; + if (nla_put_u8(skb, SMC_NLA_LGR_R_BUF_TYPE, lgr->buf_type)) + goto errattr; + if (nla_put_u8(skb, SMC_NLA_LGR_R_VLAN_ID, lgr->vlan_id)) + goto errattr; + if (nla_put_u64_64bit(skb, SMC_NLA_LGR_R_NET_COOKIE, + lgr->net->net_cookie, SMC_NLA_LGR_R_PAD)) + goto errattr; + memcpy(smc_target, lgr->pnet_id, SMC_MAX_PNETID_LEN); + smc_target[SMC_MAX_PNETID_LEN] = 0; + if (nla_put_string(skb, SMC_NLA_LGR_R_PNETID, smc_target)) + goto errattr; + if (lgr->smc_version > SMC_V1) { + v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2_COMMON); + if (!v2_attrs) + goto errattr; + if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs)) + goto errattr; + if (smc_nl_fill_smcr_lgr_v2(lgr, skb, cb)) + goto errattr; + } + + nla_nest_end(skb, attrs); + return 0; +errattr: + nla_nest_cancel(skb, attrs); +errout: + return -EMSGSIZE; +} + +static int smc_nl_fill_lgr_link(struct smc_link_group *lgr, + struct smc_link *link, + struct sk_buff *skb, + struct netlink_callback *cb) +{ + char smc_ibname[IB_DEVICE_NAME_MAX]; + u8 smc_gid_target[41]; + struct nlattr *attrs; + u32 link_uid = 0; + void *nlh; + + nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + &smc_gen_nl_family, NLM_F_MULTI, + SMC_NETLINK_GET_LINK_SMCR); + if (!nlh) + goto errmsg; + + attrs = nla_nest_start(skb, SMC_GEN_LINK_SMCR); + if (!attrs) + goto errout; + + if (nla_put_u8(skb, SMC_NLA_LINK_ID, link->link_id)) + goto errattr; + if (nla_put_u32(skb, SMC_NLA_LINK_STATE, link->state)) + goto errattr; + if (nla_put_u32(skb, SMC_NLA_LINK_CONN_CNT, + atomic_read(&link->conn_cnt))) + goto errattr; + if (nla_put_u8(skb, SMC_NLA_LINK_IB_PORT, link->ibport)) + goto errattr; + if (nla_put_u32(skb, SMC_NLA_LINK_NET_DEV, link->ndev_ifidx)) + goto errattr; + snprintf(smc_ibname, sizeof(smc_ibname), "%s", link->ibname); + if (nla_put_string(skb, SMC_NLA_LINK_IB_DEV, smc_ibname)) + goto errattr; + memcpy(&link_uid, link->link_uid, sizeof(link_uid)); + if (nla_put_u32(skb, SMC_NLA_LINK_UID, link_uid)) + goto errattr; + memcpy(&link_uid, link->peer_link_uid, sizeof(link_uid)); + if (nla_put_u32(skb, SMC_NLA_LINK_PEER_UID, link_uid)) + goto errattr; + memset(smc_gid_target, 0, sizeof(smc_gid_target)); + smc_gid_be16_convert(smc_gid_target, link->gid); + if (nla_put_string(skb, SMC_NLA_LINK_GID, smc_gid_target)) + goto errattr; + memset(smc_gid_target, 0, sizeof(smc_gid_target)); + smc_gid_be16_convert(smc_gid_target, link->peer_gid); + if (nla_put_string(skb, SMC_NLA_LINK_PEER_GID, smc_gid_target)) + goto errattr; + + nla_nest_end(skb, attrs); + genlmsg_end(skb, nlh); + return 0; +errattr: + nla_nest_cancel(skb, attrs); +errout: + genlmsg_cancel(skb, nlh); +errmsg: + return -EMSGSIZE; +} + +static int smc_nl_handle_lgr(struct smc_link_group *lgr, + struct sk_buff *skb, + struct netlink_callback *cb, + bool list_links) +{ + void *nlh; + int i; + + nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + &smc_gen_nl_family, NLM_F_MULTI, + SMC_NETLINK_GET_LGR_SMCR); + if (!nlh) + goto errmsg; + if (smc_nl_fill_lgr(lgr, skb, cb)) + goto errout; + + genlmsg_end(skb, nlh); + if (!list_links) + goto out; + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + if (!smc_link_usable(&lgr->lnk[i])) + continue; + if (smc_nl_fill_lgr_link(lgr, &lgr->lnk[i], skb, cb)) + goto errout; + } +out: + return 0; + +errout: + genlmsg_cancel(skb, nlh); +errmsg: + return -EMSGSIZE; +} + +static void smc_nl_fill_lgr_list(struct smc_lgr_list *smc_lgr, + struct sk_buff *skb, + struct netlink_callback *cb, + bool list_links) +{ + struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb); + struct smc_link_group *lgr; + int snum = cb_ctx->pos[0]; + int num = 0; + + spin_lock_bh(&smc_lgr->lock); + list_for_each_entry(lgr, &smc_lgr->list, list) { + if (num < snum) + goto next; + if (smc_nl_handle_lgr(lgr, skb, cb, list_links)) + goto errout; +next: + num++; + } +errout: + spin_unlock_bh(&smc_lgr->lock); + cb_ctx->pos[0] = num; +} + +static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr, + struct sk_buff *skb, + struct netlink_callback *cb) +{ + char smc_pnet[SMC_MAX_PNETID_LEN + 1]; + struct smcd_dev *smcd = lgr->smcd; + struct nlattr *attrs; + void *nlh; + + nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + &smc_gen_nl_family, NLM_F_MULTI, + SMC_NETLINK_GET_LGR_SMCD); + if (!nlh) + goto errmsg; + + attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCD); + if (!attrs) + goto errout; + + if (nla_put_u32(skb, SMC_NLA_LGR_D_ID, *((u32 *)&lgr->id))) + goto errattr; + if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_GID, + smcd->ops->get_local_gid(smcd), + SMC_NLA_LGR_D_PAD)) + goto errattr; + if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid, + SMC_NLA_LGR_D_PAD)) + goto errattr; + if (nla_put_u8(skb, SMC_NLA_LGR_D_VLAN_ID, lgr->vlan_id)) + goto errattr; + if (nla_put_u32(skb, SMC_NLA_LGR_D_CONNS_NUM, lgr->conns_num)) + goto errattr; + if (nla_put_u32(skb, SMC_NLA_LGR_D_CHID, smc_ism_get_chid(lgr->smcd))) + goto errattr; + memcpy(smc_pnet, lgr->smcd->pnetid, SMC_MAX_PNETID_LEN); + smc_pnet[SMC_MAX_PNETID_LEN] = 0; + if (nla_put_string(skb, SMC_NLA_LGR_D_PNETID, smc_pnet)) + goto errattr; + if (lgr->smc_version > SMC_V1) { + struct nlattr *v2_attrs; + + v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_D_V2_COMMON); + if (!v2_attrs) + goto errattr; + if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs)) + goto errattr; + } + nla_nest_end(skb, attrs); + genlmsg_end(skb, nlh); + return 0; + +errattr: + nla_nest_cancel(skb, attrs); +errout: + genlmsg_cancel(skb, nlh); +errmsg: + return -EMSGSIZE; +} + +static int smc_nl_handle_smcd_lgr(struct smcd_dev *dev, + struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb); + struct smc_link_group *lgr; + int snum = cb_ctx->pos[1]; + int rc = 0, num = 0; + + spin_lock_bh(&dev->lgr_lock); + list_for_each_entry(lgr, &dev->lgr_list, list) { + if (!lgr->is_smcd) + continue; + if (num < snum) + goto next; + rc = smc_nl_fill_smcd_lgr(lgr, skb, cb); + if (rc) + goto errout; +next: + num++; + } +errout: + spin_unlock_bh(&dev->lgr_lock); + cb_ctx->pos[1] = num; + return rc; +} + +static int smc_nl_fill_smcd_dev(struct smcd_dev_list *dev_list, + struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb); + struct smcd_dev *smcd_dev; + int snum = cb_ctx->pos[0]; + int rc = 0, num = 0; + + mutex_lock(&dev_list->mutex); + list_for_each_entry(smcd_dev, &dev_list->list, list) { + if (list_empty(&smcd_dev->lgr_list)) + continue; + if (num < snum) + goto next; + rc = smc_nl_handle_smcd_lgr(smcd_dev, skb, cb); + if (rc) + goto errout; +next: + num++; + } +errout: + mutex_unlock(&dev_list->mutex); + cb_ctx->pos[0] = num; + return rc; +} + +int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb) +{ + bool list_links = false; + + smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links); + return skb->len; +} + +int smcr_nl_get_link(struct sk_buff *skb, struct netlink_callback *cb) +{ + bool list_links = true; + + smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links); + return skb->len; +} + +int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb) +{ + smc_nl_fill_smcd_dev(&smcd_dev_list, skb, cb); + return skb->len; +} + +void smc_lgr_cleanup_early(struct smc_link_group *lgr) +{ + spinlock_t *lgr_lock; + + if (!lgr) + return; + + smc_lgr_list_head(lgr, &lgr_lock); + spin_lock_bh(lgr_lock); + /* do not use this link group for new connections */ + if (!list_empty(&lgr->list)) + list_del_init(&lgr->list); + spin_unlock_bh(lgr_lock); + __smc_lgr_terminate(lgr, true); +} + +static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr) +{ + int i; + + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + struct smc_link *lnk = &lgr->lnk[i]; + + if (smc_link_sendable(lnk)) + lnk->state = SMC_LNK_INACTIVE; + } + wake_up_all(&lgr->llc_msg_waiter); + wake_up_all(&lgr->llc_flow_waiter); +} + +static void smc_lgr_free(struct smc_link_group *lgr); + +static void smc_lgr_free_work(struct work_struct *work) +{ + struct smc_link_group *lgr = container_of(to_delayed_work(work), + struct smc_link_group, + free_work); + spinlock_t *lgr_lock; + bool conns; + + smc_lgr_list_head(lgr, &lgr_lock); + spin_lock_bh(lgr_lock); + if (lgr->freeing) { + spin_unlock_bh(lgr_lock); + return; + } + read_lock_bh(&lgr->conns_lock); + conns = RB_EMPTY_ROOT(&lgr->conns_all); + read_unlock_bh(&lgr->conns_lock); + if (!conns) { /* number of lgr connections is no longer zero */ + spin_unlock_bh(lgr_lock); + return; + } + list_del_init(&lgr->list); /* remove from smc_lgr_list */ + lgr->freeing = 1; /* this instance does the freeing, no new schedule */ + spin_unlock_bh(lgr_lock); + cancel_delayed_work(&lgr->free_work); + + if (!lgr->is_smcd && !lgr->terminating) + smc_llc_send_link_delete_all(lgr, true, + SMC_LLC_DEL_PROG_INIT_TERM); + if (lgr->is_smcd && !lgr->terminating) + smc_ism_signal_shutdown(lgr); + if (!lgr->is_smcd) + smcr_lgr_link_deactivate_all(lgr); + smc_lgr_free(lgr); +} + +static void smc_lgr_terminate_work(struct work_struct *work) +{ + struct smc_link_group *lgr = container_of(work, struct smc_link_group, + terminate_work); + + __smc_lgr_terminate(lgr, true); +} + +/* return next unique link id for the lgr */ +static u8 smcr_next_link_id(struct smc_link_group *lgr) +{ + u8 link_id; + int i; + + while (1) { +again: + link_id = ++lgr->next_link_id; + if (!link_id) /* skip zero as link_id */ + link_id = ++lgr->next_link_id; + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + if (smc_link_usable(&lgr->lnk[i]) && + lgr->lnk[i].link_id == link_id) + goto again; + } + break; + } + return link_id; +} + +static void smcr_copy_dev_info_to_link(struct smc_link *link) +{ + struct smc_ib_device *smcibdev = link->smcibdev; + + snprintf(link->ibname, sizeof(link->ibname), "%s", + smcibdev->ibdev->name); + link->ndev_ifidx = smcibdev->ndev_ifidx[link->ibport - 1]; +} + +int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk, + u8 link_idx, struct smc_init_info *ini) +{ + struct smc_ib_device *smcibdev; + u8 rndvec[3]; + int rc; + + if (lgr->smc_version == SMC_V2) { + lnk->smcibdev = ini->smcrv2.ib_dev_v2; + lnk->ibport = ini->smcrv2.ib_port_v2; + } else { + lnk->smcibdev = ini->ib_dev; + lnk->ibport = ini->ib_port; + } + get_device(&lnk->smcibdev->ibdev->dev); + atomic_inc(&lnk->smcibdev->lnk_cnt); + refcount_set(&lnk->refcnt, 1); /* link refcnt is set to 1 */ + lnk->clearing = 0; + lnk->path_mtu = lnk->smcibdev->pattr[lnk->ibport - 1].active_mtu; + lnk->link_id = smcr_next_link_id(lgr); + lnk->lgr = lgr; + smc_lgr_hold(lgr); /* lgr_put in smcr_link_clear() */ + lnk->link_idx = link_idx; + lnk->wr_rx_id_compl = 0; + smc_ibdev_cnt_inc(lnk); + smcr_copy_dev_info_to_link(lnk); + atomic_set(&lnk->conn_cnt, 0); + smc_llc_link_set_uid(lnk); + INIT_WORK(&lnk->link_down_wrk, smc_link_down_work); + if (!lnk->smcibdev->initialized) { + rc = (int)smc_ib_setup_per_ibdev(lnk->smcibdev); + if (rc) + goto out; + } + get_random_bytes(rndvec, sizeof(rndvec)); + lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) + + (rndvec[2] << 16); + rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport, + ini->vlan_id, lnk->gid, &lnk->sgid_index, + lgr->smc_version == SMC_V2 ? + &ini->smcrv2 : NULL); + if (rc) + goto out; + rc = smc_llc_link_init(lnk); + if (rc) + goto out; + rc = smc_wr_alloc_link_mem(lnk); + if (rc) + goto clear_llc_lnk; + rc = smc_ib_create_protection_domain(lnk); + if (rc) + goto free_link_mem; + rc = smc_ib_create_queue_pair(lnk); + if (rc) + goto dealloc_pd; + rc = smc_wr_create_link(lnk); + if (rc) + goto destroy_qp; + lnk->state = SMC_LNK_ACTIVATING; + return 0; + +destroy_qp: + smc_ib_destroy_queue_pair(lnk); +dealloc_pd: + smc_ib_dealloc_protection_domain(lnk); +free_link_mem: + smc_wr_free_link_mem(lnk); +clear_llc_lnk: + smc_llc_link_clear(lnk, false); +out: + smc_ibdev_cnt_dec(lnk); + put_device(&lnk->smcibdev->ibdev->dev); + smcibdev = lnk->smcibdev; + memset(lnk, 0, sizeof(struct smc_link)); + lnk->state = SMC_LNK_UNUSED; + if (!atomic_dec_return(&smcibdev->lnk_cnt)) + wake_up(&smcibdev->lnks_deleted); + smc_lgr_put(lgr); /* lgr_hold above */ + return rc; +} + +/* create a new SMC link group */ +static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini) +{ + struct smc_link_group *lgr; + struct list_head *lgr_list; + struct smcd_dev *smcd; + struct smc_link *lnk; + spinlock_t *lgr_lock; + u8 link_idx; + int rc = 0; + int i; + + if (ini->is_smcd && ini->vlan_id) { + if (smc_ism_get_vlan(ini->ism_dev[ini->ism_selected], + ini->vlan_id)) { + rc = SMC_CLC_DECL_ISMVLANERR; + goto out; + } + } + + lgr = kzalloc(sizeof(*lgr), GFP_KERNEL); + if (!lgr) { + rc = SMC_CLC_DECL_MEM; + goto ism_put_vlan; + } + lgr->tx_wq = alloc_workqueue("smc_tx_wq-%*phN", 0, 0, + SMC_LGR_ID_SIZE, &lgr->id); + if (!lgr->tx_wq) { + rc = -ENOMEM; + goto free_lgr; + } + lgr->is_smcd = ini->is_smcd; + lgr->sync_err = 0; + lgr->terminating = 0; + lgr->freeing = 0; + lgr->vlan_id = ini->vlan_id; + refcount_set(&lgr->refcnt, 1); /* set lgr refcnt to 1 */ + init_rwsem(&lgr->sndbufs_lock); + init_rwsem(&lgr->rmbs_lock); + rwlock_init(&lgr->conns_lock); + for (i = 0; i < SMC_RMBE_SIZES; i++) { + INIT_LIST_HEAD(&lgr->sndbufs[i]); + INIT_LIST_HEAD(&lgr->rmbs[i]); + } + lgr->next_link_id = 0; + smc_lgr_list.num += SMC_LGR_NUM_INCR; + memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE); + INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work); + INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work); + lgr->conns_all = RB_ROOT; + if (ini->is_smcd) { + /* SMC-D specific settings */ + smcd = ini->ism_dev[ini->ism_selected]; + get_device(smcd->ops->get_dev(smcd)); + lgr->peer_gid = ini->ism_peer_gid[ini->ism_selected]; + lgr->smcd = ini->ism_dev[ini->ism_selected]; + lgr_list = &ini->ism_dev[ini->ism_selected]->lgr_list; + lgr_lock = &lgr->smcd->lgr_lock; + lgr->smc_version = ini->smcd_version; + lgr->peer_shutdown = 0; + atomic_inc(&ini->ism_dev[ini->ism_selected]->lgr_cnt); + } else { + /* SMC-R specific settings */ + struct smc_ib_device *ibdev; + int ibport; + + lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT; + lgr->smc_version = ini->smcr_version; + memcpy(lgr->peer_systemid, ini->peer_systemid, + SMC_SYSTEMID_LEN); + if (lgr->smc_version == SMC_V2) { + ibdev = ini->smcrv2.ib_dev_v2; + ibport = ini->smcrv2.ib_port_v2; + lgr->saddr = ini->smcrv2.saddr; + lgr->uses_gateway = ini->smcrv2.uses_gateway; + memcpy(lgr->nexthop_mac, ini->smcrv2.nexthop_mac, + ETH_ALEN); + lgr->max_conns = ini->max_conns; + lgr->max_links = ini->max_links; + } else { + ibdev = ini->ib_dev; + ibport = ini->ib_port; + lgr->max_conns = SMC_CONN_PER_LGR_MAX; + lgr->max_links = SMC_LINKS_ADD_LNK_MAX; + } + memcpy(lgr->pnet_id, ibdev->pnetid[ibport - 1], + SMC_MAX_PNETID_LEN); + rc = smc_wr_alloc_lgr_mem(lgr); + if (rc) + goto free_wq; + smc_llc_lgr_init(lgr, smc); + + link_idx = SMC_SINGLE_LINK; + lnk = &lgr->lnk[link_idx]; + rc = smcr_link_init(lgr, lnk, link_idx, ini); + if (rc) { + smc_wr_free_lgr_mem(lgr); + goto free_wq; + } + lgr->net = smc_ib_net(lnk->smcibdev); + lgr_list = &smc_lgr_list.list; + lgr_lock = &smc_lgr_list.lock; + lgr->buf_type = lgr->net->smc.sysctl_smcr_buf_type; + atomic_inc(&lgr_cnt); + } + smc->conn.lgr = lgr; + spin_lock_bh(lgr_lock); + list_add_tail(&lgr->list, lgr_list); + spin_unlock_bh(lgr_lock); + return 0; + +free_wq: + destroy_workqueue(lgr->tx_wq); +free_lgr: + kfree(lgr); +ism_put_vlan: + if (ini->is_smcd && ini->vlan_id) + smc_ism_put_vlan(ini->ism_dev[ini->ism_selected], ini->vlan_id); +out: + if (rc < 0) { + if (rc == -ENOMEM) + rc = SMC_CLC_DECL_MEM; + else + rc = SMC_CLC_DECL_INTERR; + } + return rc; +} + +static int smc_write_space(struct smc_connection *conn) +{ + int buffer_len = conn->peer_rmbe_size; + union smc_host_cursor prod; + union smc_host_cursor cons; + int space; + + smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn); + smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn); + /* determine rx_buf space */ + space = buffer_len - smc_curs_diff(buffer_len, &cons, &prod); + return space; +} + +static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend, + struct smc_wr_buf *wr_buf) +{ + struct smc_connection *conn = &smc->conn; + union smc_host_cursor cons, fin; + int rc = 0; + int diff; + + smc_curs_copy(&conn->tx_curs_sent, &conn->tx_curs_fin, conn); + smc_curs_copy(&fin, &conn->local_tx_ctrl_fin, conn); + /* set prod cursor to old state, enforce tx_rdma_writes() */ + smc_curs_copy(&conn->local_tx_ctrl.prod, &fin, conn); + smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn); + + if (smc_curs_comp(conn->peer_rmbe_size, &cons, &fin) < 0) { + /* cons cursor advanced more than fin, and prod was set + * fin above, so now prod is smaller than cons. Fix that. + */ + diff = smc_curs_diff(conn->peer_rmbe_size, &fin, &cons); + smc_curs_add(conn->sndbuf_desc->len, + &conn->tx_curs_sent, diff); + smc_curs_add(conn->sndbuf_desc->len, + &conn->tx_curs_fin, diff); + + smp_mb__before_atomic(); + atomic_add(diff, &conn->sndbuf_space); + smp_mb__after_atomic(); + + smc_curs_add(conn->peer_rmbe_size, + &conn->local_tx_ctrl.prod, diff); + smc_curs_add(conn->peer_rmbe_size, + &conn->local_tx_ctrl_fin, diff); + } + /* recalculate, value is used by tx_rdma_writes() */ + atomic_set(&smc->conn.peer_rmbe_space, smc_write_space(conn)); + + if (smc->sk.sk_state != SMC_INIT && + smc->sk.sk_state != SMC_CLOSED) { + rc = smcr_cdc_msg_send_validation(conn, pend, wr_buf); + if (!rc) { + queue_delayed_work(conn->lgr->tx_wq, &conn->tx_work, 0); + smc->sk.sk_data_ready(&smc->sk); + } + } else { + smc_wr_tx_put_slot(conn->lnk, + (struct smc_wr_tx_pend_priv *)pend); + } + return rc; +} + +void smc_switch_link_and_count(struct smc_connection *conn, + struct smc_link *to_lnk) +{ + atomic_dec(&conn->lnk->conn_cnt); + /* link_hold in smc_conn_create() */ + smcr_link_put(conn->lnk); + conn->lnk = to_lnk; + atomic_inc(&conn->lnk->conn_cnt); + /* link_put in smc_conn_free() */ + smcr_link_hold(conn->lnk); +} + +struct smc_link *smc_switch_conns(struct smc_link_group *lgr, + struct smc_link *from_lnk, bool is_dev_err) +{ + struct smc_link *to_lnk = NULL; + struct smc_cdc_tx_pend *pend; + struct smc_connection *conn; + struct smc_wr_buf *wr_buf; + struct smc_sock *smc; + struct rb_node *node; + int i, rc = 0; + + /* link is inactive, wake up tx waiters */ + smc_wr_wakeup_tx_wait(from_lnk); + + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + if (!smc_link_active(&lgr->lnk[i]) || i == from_lnk->link_idx) + continue; + if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev && + from_lnk->ibport == lgr->lnk[i].ibport) { + continue; + } + to_lnk = &lgr->lnk[i]; + break; + } + if (!to_lnk || !smc_wr_tx_link_hold(to_lnk)) { + smc_lgr_terminate_sched(lgr); + return NULL; + } +again: + read_lock_bh(&lgr->conns_lock); + for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) { + conn = rb_entry(node, struct smc_connection, alert_node); + if (conn->lnk != from_lnk) + continue; + smc = container_of(conn, struct smc_sock, conn); + /* conn->lnk not yet set in SMC_INIT state */ + if (smc->sk.sk_state == SMC_INIT) + continue; + if (smc->sk.sk_state == SMC_CLOSED || + smc->sk.sk_state == SMC_PEERCLOSEWAIT1 || + smc->sk.sk_state == SMC_PEERCLOSEWAIT2 || + smc->sk.sk_state == SMC_APPFINCLOSEWAIT || + smc->sk.sk_state == SMC_APPCLOSEWAIT1 || + smc->sk.sk_state == SMC_APPCLOSEWAIT2 || + smc->sk.sk_state == SMC_PEERFINCLOSEWAIT || + smc->sk.sk_state == SMC_PEERABORTWAIT || + smc->sk.sk_state == SMC_PROCESSABORT) { + spin_lock_bh(&conn->send_lock); + smc_switch_link_and_count(conn, to_lnk); + spin_unlock_bh(&conn->send_lock); + continue; + } + sock_hold(&smc->sk); + read_unlock_bh(&lgr->conns_lock); + /* pre-fetch buffer outside of send_lock, might sleep */ + rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend); + if (rc) + goto err_out; + /* avoid race with smcr_tx_sndbuf_nonempty() */ + spin_lock_bh(&conn->send_lock); + smc_switch_link_and_count(conn, to_lnk); + rc = smc_switch_cursor(smc, pend, wr_buf); + spin_unlock_bh(&conn->send_lock); + sock_put(&smc->sk); + if (rc) + goto err_out; + goto again; + } + read_unlock_bh(&lgr->conns_lock); + smc_wr_tx_link_put(to_lnk); + return to_lnk; + +err_out: + smcr_link_down_cond_sched(to_lnk); + smc_wr_tx_link_put(to_lnk); + return NULL; +} + +static void smcr_buf_unuse(struct smc_buf_desc *buf_desc, bool is_rmb, + struct smc_link_group *lgr) +{ + struct rw_semaphore *lock; /* lock buffer list */ + int rc; + + if (is_rmb && buf_desc->is_conf_rkey && !list_empty(&lgr->list)) { + /* unregister rmb with peer */ + rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY); + if (!rc) { + /* protect against smc_llc_cli_rkey_exchange() */ + down_read(&lgr->llc_conf_mutex); + smc_llc_do_delete_rkey(lgr, buf_desc); + buf_desc->is_conf_rkey = false; + up_read(&lgr->llc_conf_mutex); + smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl); + } + } + + if (buf_desc->is_reg_err) { + /* buf registration failed, reuse not possible */ + lock = is_rmb ? &lgr->rmbs_lock : + &lgr->sndbufs_lock; + down_write(lock); + list_del(&buf_desc->list); + up_write(lock); + + smc_buf_free(lgr, is_rmb, buf_desc); + } else { + /* memzero_explicit provides potential memory barrier semantics */ + memzero_explicit(buf_desc->cpu_addr, buf_desc->len); + WRITE_ONCE(buf_desc->used, 0); + } +} + +static void smc_buf_unuse(struct smc_connection *conn, + struct smc_link_group *lgr) +{ + if (conn->sndbuf_desc) { + if (!lgr->is_smcd && conn->sndbuf_desc->is_vm) { + smcr_buf_unuse(conn->sndbuf_desc, false, lgr); + } else { + memzero_explicit(conn->sndbuf_desc->cpu_addr, conn->sndbuf_desc->len); + WRITE_ONCE(conn->sndbuf_desc->used, 0); + } + } + if (conn->rmb_desc) { + if (!lgr->is_smcd) { + smcr_buf_unuse(conn->rmb_desc, true, lgr); + } else { + memzero_explicit(conn->rmb_desc->cpu_addr, + conn->rmb_desc->len + sizeof(struct smcd_cdc_msg)); + WRITE_ONCE(conn->rmb_desc->used, 0); + } + } +} + +/* remove a finished connection from its link group */ +void smc_conn_free(struct smc_connection *conn) +{ + struct smc_link_group *lgr = conn->lgr; + + if (!lgr || conn->freed) + /* Connection has never been registered in a + * link group, or has already been freed. + */ + return; + + conn->freed = 1; + if (!smc_conn_lgr_valid(conn)) + /* Connection has already unregistered from + * link group. + */ + goto lgr_put; + + if (lgr->is_smcd) { + if (!list_empty(&lgr->list)) + smc_ism_unset_conn(conn); + tasklet_kill(&conn->rx_tsklet); + } else { + smc_cdc_wait_pend_tx_wr(conn); + if (current_work() != &conn->abort_work) + cancel_work_sync(&conn->abort_work); + } + if (!list_empty(&lgr->list)) { + smc_buf_unuse(conn, lgr); /* allow buffer reuse */ + smc_lgr_unregister_conn(conn); + } + + if (!lgr->conns_num) + smc_lgr_schedule_free_work(lgr); +lgr_put: + if (!lgr->is_smcd) + smcr_link_put(conn->lnk); /* link_hold in smc_conn_create() */ + smc_lgr_put(lgr); /* lgr_hold in smc_conn_create() */ +} + +/* unregister a link from a buf_desc */ +static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb, + struct smc_link *lnk) +{ + if (is_rmb || buf_desc->is_vm) + buf_desc->is_reg_mr[lnk->link_idx] = false; + if (!buf_desc->is_map_ib[lnk->link_idx]) + return; + + if ((is_rmb || buf_desc->is_vm) && + buf_desc->mr[lnk->link_idx]) { + smc_ib_put_memory_region(buf_desc->mr[lnk->link_idx]); + buf_desc->mr[lnk->link_idx] = NULL; + } + if (is_rmb) + smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_FROM_DEVICE); + else + smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_TO_DEVICE); + + sg_free_table(&buf_desc->sgt[lnk->link_idx]); + buf_desc->is_map_ib[lnk->link_idx] = false; +} + +/* unmap all buffers of lgr for a deleted link */ +static void smcr_buf_unmap_lgr(struct smc_link *lnk) +{ + struct smc_link_group *lgr = lnk->lgr; + struct smc_buf_desc *buf_desc, *bf; + int i; + + for (i = 0; i < SMC_RMBE_SIZES; i++) { + down_write(&lgr->rmbs_lock); + list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) + smcr_buf_unmap_link(buf_desc, true, lnk); + up_write(&lgr->rmbs_lock); + + down_write(&lgr->sndbufs_lock); + list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i], + list) + smcr_buf_unmap_link(buf_desc, false, lnk); + up_write(&lgr->sndbufs_lock); + } +} + +static void smcr_rtoken_clear_link(struct smc_link *lnk) +{ + struct smc_link_group *lgr = lnk->lgr; + int i; + + for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) { + lgr->rtokens[i][lnk->link_idx].rkey = 0; + lgr->rtokens[i][lnk->link_idx].dma_addr = 0; + } +} + +static void __smcr_link_clear(struct smc_link *lnk) +{ + struct smc_link_group *lgr = lnk->lgr; + struct smc_ib_device *smcibdev; + + smc_wr_free_link_mem(lnk); + smc_ibdev_cnt_dec(lnk); + put_device(&lnk->smcibdev->ibdev->dev); + smcibdev = lnk->smcibdev; + memset(lnk, 0, sizeof(struct smc_link)); + lnk->state = SMC_LNK_UNUSED; + if (!atomic_dec_return(&smcibdev->lnk_cnt)) + wake_up(&smcibdev->lnks_deleted); + smc_lgr_put(lgr); /* lgr_hold in smcr_link_init() */ +} + +/* must be called under lgr->llc_conf_mutex lock */ +void smcr_link_clear(struct smc_link *lnk, bool log) +{ + if (!lnk->lgr || lnk->clearing || + lnk->state == SMC_LNK_UNUSED) + return; + lnk->clearing = 1; + lnk->peer_qpn = 0; + smc_llc_link_clear(lnk, log); + smcr_buf_unmap_lgr(lnk); + smcr_rtoken_clear_link(lnk); + smc_ib_modify_qp_error(lnk); + smc_wr_free_link(lnk); + smc_ib_destroy_queue_pair(lnk); + smc_ib_dealloc_protection_domain(lnk); + smcr_link_put(lnk); /* theoretically last link_put */ +} + +void smcr_link_hold(struct smc_link *lnk) +{ + refcount_inc(&lnk->refcnt); +} + +void smcr_link_put(struct smc_link *lnk) +{ + if (refcount_dec_and_test(&lnk->refcnt)) + __smcr_link_clear(lnk); +} + +static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb, + struct smc_buf_desc *buf_desc) +{ + int i; + + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) + smcr_buf_unmap_link(buf_desc, is_rmb, &lgr->lnk[i]); + + if (!buf_desc->is_vm && buf_desc->pages) + __free_pages(buf_desc->pages, buf_desc->order); + else if (buf_desc->is_vm && buf_desc->cpu_addr) + vfree(buf_desc->cpu_addr); + kfree(buf_desc); +} + +static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb, + struct smc_buf_desc *buf_desc) +{ + if (is_dmb) { + /* restore original buf len */ + buf_desc->len += sizeof(struct smcd_cdc_msg); + smc_ism_unregister_dmb(lgr->smcd, buf_desc); + } else { + kfree(buf_desc->cpu_addr); + } + kfree(buf_desc); +} + +static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb, + struct smc_buf_desc *buf_desc) +{ + if (lgr->is_smcd) + smcd_buf_free(lgr, is_rmb, buf_desc); + else + smcr_buf_free(lgr, is_rmb, buf_desc); +} + +static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb) +{ + struct smc_buf_desc *buf_desc, *bf_desc; + struct list_head *buf_list; + int i; + + for (i = 0; i < SMC_RMBE_SIZES; i++) { + if (is_rmb) + buf_list = &lgr->rmbs[i]; + else + buf_list = &lgr->sndbufs[i]; + list_for_each_entry_safe(buf_desc, bf_desc, buf_list, + list) { + list_del(&buf_desc->list); + smc_buf_free(lgr, is_rmb, buf_desc); + } + } +} + +static void smc_lgr_free_bufs(struct smc_link_group *lgr) +{ + /* free send buffers */ + __smc_lgr_free_bufs(lgr, false); + /* free rmbs */ + __smc_lgr_free_bufs(lgr, true); +} + +/* won't be freed until no one accesses to lgr anymore */ +static void __smc_lgr_free(struct smc_link_group *lgr) +{ + smc_lgr_free_bufs(lgr); + if (lgr->is_smcd) { + if (!atomic_dec_return(&lgr->smcd->lgr_cnt)) + wake_up(&lgr->smcd->lgrs_deleted); + } else { + smc_wr_free_lgr_mem(lgr); + if (!atomic_dec_return(&lgr_cnt)) + wake_up(&lgrs_deleted); + } + kfree(lgr); +} + +/* remove a link group */ +static void smc_lgr_free(struct smc_link_group *lgr) +{ + int i; + + if (!lgr->is_smcd) { + down_write(&lgr->llc_conf_mutex); + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + if (lgr->lnk[i].state != SMC_LNK_UNUSED) + smcr_link_clear(&lgr->lnk[i], false); + } + up_write(&lgr->llc_conf_mutex); + smc_llc_lgr_clear(lgr); + } + + destroy_workqueue(lgr->tx_wq); + if (lgr->is_smcd) { + smc_ism_put_vlan(lgr->smcd, lgr->vlan_id); + put_device(lgr->smcd->ops->get_dev(lgr->smcd)); + } + smc_lgr_put(lgr); /* theoretically last lgr_put */ +} + +void smc_lgr_hold(struct smc_link_group *lgr) +{ + refcount_inc(&lgr->refcnt); +} + +void smc_lgr_put(struct smc_link_group *lgr) +{ + if (refcount_dec_and_test(&lgr->refcnt)) + __smc_lgr_free(lgr); +} + +static void smc_sk_wake_ups(struct smc_sock *smc) +{ + smc->sk.sk_write_space(&smc->sk); + smc->sk.sk_data_ready(&smc->sk); + smc->sk.sk_state_change(&smc->sk); +} + +/* kill a connection */ +static void smc_conn_kill(struct smc_connection *conn, bool soft) +{ + struct smc_sock *smc = container_of(conn, struct smc_sock, conn); + + if (conn->lgr->is_smcd && conn->lgr->peer_shutdown) + conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1; + else + smc_close_abort(conn); + conn->killed = 1; + smc->sk.sk_err = ECONNABORTED; + smc_sk_wake_ups(smc); + if (conn->lgr->is_smcd) { + smc_ism_unset_conn(conn); + if (soft) + tasklet_kill(&conn->rx_tsklet); + else + tasklet_unlock_wait(&conn->rx_tsklet); + } else { + smc_cdc_wait_pend_tx_wr(conn); + } + smc_lgr_unregister_conn(conn); + smc_close_active_abort(smc); +} + +static void smc_lgr_cleanup(struct smc_link_group *lgr) +{ + if (lgr->is_smcd) { + smc_ism_signal_shutdown(lgr); + } else { + u32 rsn = lgr->llc_termination_rsn; + + if (!rsn) + rsn = SMC_LLC_DEL_PROG_INIT_TERM; + smc_llc_send_link_delete_all(lgr, false, rsn); + smcr_lgr_link_deactivate_all(lgr); + } +} + +/* terminate link group + * @soft: true if link group shutdown can take its time + * false if immediate link group shutdown is required + */ +static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft) +{ + struct smc_connection *conn; + struct smc_sock *smc; + struct rb_node *node; + + if (lgr->terminating) + return; /* lgr already terminating */ + /* cancel free_work sync, will terminate when lgr->freeing is set */ + cancel_delayed_work(&lgr->free_work); + lgr->terminating = 1; + + /* kill remaining link group connections */ + read_lock_bh(&lgr->conns_lock); + node = rb_first(&lgr->conns_all); + while (node) { + read_unlock_bh(&lgr->conns_lock); + conn = rb_entry(node, struct smc_connection, alert_node); + smc = container_of(conn, struct smc_sock, conn); + sock_hold(&smc->sk); /* sock_put below */ + lock_sock(&smc->sk); + smc_conn_kill(conn, soft); + release_sock(&smc->sk); + sock_put(&smc->sk); /* sock_hold above */ + read_lock_bh(&lgr->conns_lock); + node = rb_first(&lgr->conns_all); + } + read_unlock_bh(&lgr->conns_lock); + smc_lgr_cleanup(lgr); + smc_lgr_free(lgr); +} + +/* unlink link group and schedule termination */ +void smc_lgr_terminate_sched(struct smc_link_group *lgr) +{ + spinlock_t *lgr_lock; + + smc_lgr_list_head(lgr, &lgr_lock); + spin_lock_bh(lgr_lock); + if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) { + spin_unlock_bh(lgr_lock); + return; /* lgr already terminating */ + } + list_del_init(&lgr->list); + lgr->freeing = 1; + spin_unlock_bh(lgr_lock); + schedule_work(&lgr->terminate_work); +} + +/* Called when peer lgr shutdown (regularly or abnormally) is received */ +void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan) +{ + struct smc_link_group *lgr, *l; + LIST_HEAD(lgr_free_list); + + /* run common cleanup function and build free list */ + spin_lock_bh(&dev->lgr_lock); + list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) { + if ((!peer_gid || lgr->peer_gid == peer_gid) && + (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) { + if (peer_gid) /* peer triggered termination */ + lgr->peer_shutdown = 1; + list_move(&lgr->list, &lgr_free_list); + lgr->freeing = 1; + } + } + spin_unlock_bh(&dev->lgr_lock); + + /* cancel the regular free workers and actually free lgrs */ + list_for_each_entry_safe(lgr, l, &lgr_free_list, list) { + list_del_init(&lgr->list); + schedule_work(&lgr->terminate_work); + } +} + +/* Called when an SMCD device is removed or the smc module is unloaded */ +void smc_smcd_terminate_all(struct smcd_dev *smcd) +{ + struct smc_link_group *lgr, *lg; + LIST_HEAD(lgr_free_list); + + spin_lock_bh(&smcd->lgr_lock); + list_splice_init(&smcd->lgr_list, &lgr_free_list); + list_for_each_entry(lgr, &lgr_free_list, list) + lgr->freeing = 1; + spin_unlock_bh(&smcd->lgr_lock); + + list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) { + list_del_init(&lgr->list); + __smc_lgr_terminate(lgr, false); + } + + if (atomic_read(&smcd->lgr_cnt)) + wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt)); +} + +/* Called when an SMCR device is removed or the smc module is unloaded. + * If smcibdev is given, all SMCR link groups using this device are terminated. + * If smcibdev is NULL, all SMCR link groups are terminated. + */ +void smc_smcr_terminate_all(struct smc_ib_device *smcibdev) +{ + struct smc_link_group *lgr, *lg; + LIST_HEAD(lgr_free_list); + int i; + + spin_lock_bh(&smc_lgr_list.lock); + if (!smcibdev) { + list_splice_init(&smc_lgr_list.list, &lgr_free_list); + list_for_each_entry(lgr, &lgr_free_list, list) + lgr->freeing = 1; + } else { + list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) { + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + if (lgr->lnk[i].smcibdev == smcibdev) + smcr_link_down_cond_sched(&lgr->lnk[i]); + } + } + } + spin_unlock_bh(&smc_lgr_list.lock); + + list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) { + list_del_init(&lgr->list); + smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM); + __smc_lgr_terminate(lgr, false); + } + + if (smcibdev) { + if (atomic_read(&smcibdev->lnk_cnt)) + wait_event(smcibdev->lnks_deleted, + !atomic_read(&smcibdev->lnk_cnt)); + } else { + if (atomic_read(&lgr_cnt)) + wait_event(lgrs_deleted, !atomic_read(&lgr_cnt)); + } +} + +/* set new lgr type and clear all asymmetric link tagging */ +void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type) +{ + char *lgr_type = ""; + int i; + + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) + if (smc_link_usable(&lgr->lnk[i])) + lgr->lnk[i].link_is_asym = false; + if (lgr->type == new_type) + return; + lgr->type = new_type; + + switch (lgr->type) { + case SMC_LGR_NONE: + lgr_type = "NONE"; + break; + case SMC_LGR_SINGLE: + lgr_type = "SINGLE"; + break; + case SMC_LGR_SYMMETRIC: + lgr_type = "SYMMETRIC"; + break; + case SMC_LGR_ASYMMETRIC_PEER: + lgr_type = "ASYMMETRIC_PEER"; + break; + case SMC_LGR_ASYMMETRIC_LOCAL: + lgr_type = "ASYMMETRIC_LOCAL"; + break; + } + pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu state changed: " + "%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id, + lgr->net->net_cookie, lgr_type, lgr->pnet_id); +} + +/* set new lgr type and tag a link as asymmetric */ +void smcr_lgr_set_type_asym(struct smc_link_group *lgr, + enum smc_lgr_type new_type, int asym_lnk_idx) +{ + smcr_lgr_set_type(lgr, new_type); + lgr->lnk[asym_lnk_idx].link_is_asym = true; +} + +/* abort connection, abort_work scheduled from tasklet context */ +static void smc_conn_abort_work(struct work_struct *work) +{ + struct smc_connection *conn = container_of(work, + struct smc_connection, + abort_work); + struct smc_sock *smc = container_of(conn, struct smc_sock, conn); + + lock_sock(&smc->sk); + smc_conn_kill(conn, true); + release_sock(&smc->sk); + sock_put(&smc->sk); /* sock_hold done by schedulers of abort_work */ +} + +void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport) +{ + struct smc_link_group *lgr, *n; + + spin_lock_bh(&smc_lgr_list.lock); + list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) { + struct smc_link *link; + + if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id, + SMC_MAX_PNETID_LEN) || + lgr->type == SMC_LGR_SYMMETRIC || + lgr->type == SMC_LGR_ASYMMETRIC_PEER || + !rdma_dev_access_netns(smcibdev->ibdev, lgr->net)) + continue; + + if (lgr->type == SMC_LGR_SINGLE && lgr->max_links <= 1) + continue; + + /* trigger local add link processing */ + link = smc_llc_usable_link(lgr); + if (link) + smc_llc_add_link_local(link); + } + spin_unlock_bh(&smc_lgr_list.lock); +} + +/* link is down - switch connections to alternate link, + * must be called under lgr->llc_conf_mutex lock + */ +static void smcr_link_down(struct smc_link *lnk) +{ + struct smc_link_group *lgr = lnk->lgr; + struct smc_link *to_lnk; + int del_link_id; + + if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(&lgr->list)) + return; + + to_lnk = smc_switch_conns(lgr, lnk, true); + if (!to_lnk) { /* no backup link available */ + smcr_link_clear(lnk, true); + return; + } + smcr_lgr_set_type(lgr, SMC_LGR_SINGLE); + del_link_id = lnk->link_id; + + if (lgr->role == SMC_SERV) { + /* trigger local delete link processing */ + smc_llc_srv_delete_link_local(to_lnk, del_link_id); + } else { + if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) { + /* another llc task is ongoing */ + up_write(&lgr->llc_conf_mutex); + wait_event_timeout(lgr->llc_flow_waiter, + (list_empty(&lgr->list) || + lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE), + SMC_LLC_WAIT_TIME); + down_write(&lgr->llc_conf_mutex); + } + if (!list_empty(&lgr->list)) { + smc_llc_send_delete_link(to_lnk, del_link_id, + SMC_LLC_REQ, true, + SMC_LLC_DEL_LOST_PATH); + smcr_link_clear(lnk, true); + } + wake_up(&lgr->llc_flow_waiter); /* wake up next waiter */ + } +} + +/* must be called under lgr->llc_conf_mutex lock */ +void smcr_link_down_cond(struct smc_link *lnk) +{ + if (smc_link_downing(&lnk->state)) { + trace_smcr_link_down(lnk, __builtin_return_address(0)); + smcr_link_down(lnk); + } +} + +/* will get the lgr->llc_conf_mutex lock */ +void smcr_link_down_cond_sched(struct smc_link *lnk) +{ + if (smc_link_downing(&lnk->state)) { + trace_smcr_link_down(lnk, __builtin_return_address(0)); + schedule_work(&lnk->link_down_wrk); + } +} + +void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport) +{ + struct smc_link_group *lgr, *n; + int i; + + list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) { + if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id, + SMC_MAX_PNETID_LEN)) + continue; /* lgr is not affected */ + if (list_empty(&lgr->list)) + continue; + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + struct smc_link *lnk = &lgr->lnk[i]; + + if (smc_link_usable(lnk) && + lnk->smcibdev == smcibdev && lnk->ibport == ibport) + smcr_link_down_cond_sched(lnk); + } + } +} + +static void smc_link_down_work(struct work_struct *work) +{ + struct smc_link *link = container_of(work, struct smc_link, + link_down_wrk); + struct smc_link_group *lgr = link->lgr; + + if (list_empty(&lgr->list)) + return; + wake_up_all(&lgr->llc_msg_waiter); + down_write(&lgr->llc_conf_mutex); + smcr_link_down(link); + up_write(&lgr->llc_conf_mutex); +} + +static int smc_vlan_by_tcpsk_walk(struct net_device *lower_dev, + struct netdev_nested_priv *priv) +{ + unsigned short *vlan_id = (unsigned short *)priv->data; + + if (is_vlan_dev(lower_dev)) { + *vlan_id = vlan_dev_vlan_id(lower_dev); + return 1; + } + + return 0; +} + +/* Determine vlan of internal TCP socket. */ +int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini) +{ + struct dst_entry *dst = sk_dst_get(clcsock->sk); + struct netdev_nested_priv priv; + struct net_device *ndev; + int rc = 0; + + ini->vlan_id = 0; + if (!dst) { + rc = -ENOTCONN; + goto out; + } + if (!dst->dev) { + rc = -ENODEV; + goto out_rel; + } + + ndev = dst->dev; + if (is_vlan_dev(ndev)) { + ini->vlan_id = vlan_dev_vlan_id(ndev); + goto out_rel; + } + + priv.data = (void *)&ini->vlan_id; + rtnl_lock(); + netdev_walk_all_lower_dev(ndev, smc_vlan_by_tcpsk_walk, &priv); + rtnl_unlock(); + +out_rel: + dst_release(dst); +out: + return rc; +} + +static bool smcr_lgr_match(struct smc_link_group *lgr, u8 smcr_version, + u8 peer_systemid[], + u8 peer_gid[], + u8 peer_mac_v1[], + enum smc_lgr_role role, u32 clcqpn, + struct net *net) +{ + struct smc_link *lnk; + int i; + + if (memcmp(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN) || + lgr->role != role) + return false; + + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + lnk = &lgr->lnk[i]; + + if (!smc_link_active(lnk)) + continue; + /* use verbs API to check netns, instead of lgr->net */ + if (!rdma_dev_access_netns(lnk->smcibdev->ibdev, net)) + return false; + if ((lgr->role == SMC_SERV || lnk->peer_qpn == clcqpn) && + !memcmp(lnk->peer_gid, peer_gid, SMC_GID_SIZE) && + (smcr_version == SMC_V2 || + !memcmp(lnk->peer_mac, peer_mac_v1, ETH_ALEN))) + return true; + } + return false; +} + +static bool smcd_lgr_match(struct smc_link_group *lgr, + struct smcd_dev *smcismdev, u64 peer_gid) +{ + return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev; +} + +/* create a new SMC connection (and a new link group if necessary) */ +int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini) +{ + struct smc_connection *conn = &smc->conn; + struct net *net = sock_net(&smc->sk); + struct list_head *lgr_list; + struct smc_link_group *lgr; + enum smc_lgr_role role; + spinlock_t *lgr_lock; + int rc = 0; + + lgr_list = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_list : + &smc_lgr_list.list; + lgr_lock = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_lock : + &smc_lgr_list.lock; + ini->first_contact_local = 1; + role = smc->listen_smc ? SMC_SERV : SMC_CLNT; + if (role == SMC_CLNT && ini->first_contact_peer) + /* create new link group as well */ + goto create; + + /* determine if an existing link group can be reused */ + spin_lock_bh(lgr_lock); + list_for_each_entry(lgr, lgr_list, list) { + write_lock_bh(&lgr->conns_lock); + if ((ini->is_smcd ? + smcd_lgr_match(lgr, ini->ism_dev[ini->ism_selected], + ini->ism_peer_gid[ini->ism_selected]) : + smcr_lgr_match(lgr, ini->smcr_version, + ini->peer_systemid, + ini->peer_gid, ini->peer_mac, role, + ini->ib_clcqpn, net)) && + !lgr->sync_err && + (ini->smcd_version == SMC_V2 || + lgr->vlan_id == ini->vlan_id) && + (role == SMC_CLNT || ini->is_smcd || + (lgr->conns_num < lgr->max_conns && + !bitmap_full(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX)))) { + /* link group found */ + ini->first_contact_local = 0; + conn->lgr = lgr; + rc = smc_lgr_register_conn(conn, false); + write_unlock_bh(&lgr->conns_lock); + if (!rc && delayed_work_pending(&lgr->free_work)) + cancel_delayed_work(&lgr->free_work); + break; + } + write_unlock_bh(&lgr->conns_lock); + } + spin_unlock_bh(lgr_lock); + if (rc) + return rc; + + if (role == SMC_CLNT && !ini->first_contact_peer && + ini->first_contact_local) { + /* Server reuses a link group, but Client wants to start + * a new one + * send out_of_sync decline, reason synchr. error + */ + return SMC_CLC_DECL_SYNCERR; + } + +create: + if (ini->first_contact_local) { + rc = smc_lgr_create(smc, ini); + if (rc) + goto out; + lgr = conn->lgr; + write_lock_bh(&lgr->conns_lock); + rc = smc_lgr_register_conn(conn, true); + write_unlock_bh(&lgr->conns_lock); + if (rc) { + smc_lgr_cleanup_early(lgr); + goto out; + } + } + smc_lgr_hold(conn->lgr); /* lgr_put in smc_conn_free() */ + if (!conn->lgr->is_smcd) + smcr_link_hold(conn->lnk); /* link_put in smc_conn_free() */ + conn->freed = 0; + conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE; + conn->local_tx_ctrl.len = SMC_WR_TX_SIZE; + conn->urg_state = SMC_URG_READ; + init_waitqueue_head(&conn->cdc_pend_tx_wq); + INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work); + if (ini->is_smcd) { + conn->rx_off = sizeof(struct smcd_cdc_msg); + smcd_cdc_rx_init(conn); /* init tasklet for this conn */ + } else { + conn->rx_off = 0; + } +#ifndef KERNEL_HAS_ATOMIC64 + spin_lock_init(&conn->acurs_lock); +#endif + +out: + return rc; +} + +#define SMCD_DMBE_SIZES 6 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */ +#define SMCR_RMBE_SIZES 5 /* 0 -> 16KB, 1 -> 32KB, .. 5 -> 512KB */ + +/* convert the RMB size into the compressed notation (minimum 16K, see + * SMCD/R_DMBE_SIZES. + * In contrast to plain ilog2, this rounds towards the next power of 2, + * so the socket application gets at least its desired sndbuf / rcvbuf size. + */ +static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb) +{ + const unsigned int max_scat = SG_MAX_SINGLE_ALLOC * PAGE_SIZE; + u8 compressed; + + if (size <= SMC_BUF_MIN_SIZE) + return 0; + + size = (size - 1) >> 14; /* convert to 16K multiple */ + compressed = min_t(u8, ilog2(size) + 1, + is_smcd ? SMCD_DMBE_SIZES : SMCR_RMBE_SIZES); + + if (!is_smcd && is_rmb) + /* RMBs are backed by & limited to max size of scatterlists */ + compressed = min_t(u8, compressed, ilog2(max_scat >> 14)); + + return compressed; +} + +/* convert the RMB size from compressed notation into integer */ +int smc_uncompress_bufsize(u8 compressed) +{ + u32 size; + + size = 0x00000001 << (((int)compressed) + 14); + return (int)size; +} + +/* try to reuse a sndbuf or rmb description slot for a certain + * buffer size; if not available, return NULL + */ +static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize, + struct rw_semaphore *lock, + struct list_head *buf_list) +{ + struct smc_buf_desc *buf_slot; + + down_read(lock); + list_for_each_entry(buf_slot, buf_list, list) { + if (cmpxchg(&buf_slot->used, 0, 1) == 0) { + up_read(lock); + return buf_slot; + } + } + up_read(lock); + return NULL; +} + +/* one of the conditions for announcing a receiver's current window size is + * that it "results in a minimum increase in the window size of 10% of the + * receive buffer space" [RFC7609] + */ +static inline int smc_rmb_wnd_update_limit(int rmbe_size) +{ + return max_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2); +} + +/* map an buf to a link */ +static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb, + struct smc_link *lnk) +{ + int rc, i, nents, offset, buf_size, size, access_flags; + struct scatterlist *sg; + void *buf; + + if (buf_desc->is_map_ib[lnk->link_idx]) + return 0; + + if (buf_desc->is_vm) { + buf = buf_desc->cpu_addr; + buf_size = buf_desc->len; + offset = offset_in_page(buf_desc->cpu_addr); + nents = PAGE_ALIGN(buf_size + offset) / PAGE_SIZE; + } else { + nents = 1; + } + + rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], nents, GFP_KERNEL); + if (rc) + return rc; + + if (buf_desc->is_vm) { + /* virtually contiguous buffer */ + for_each_sg(buf_desc->sgt[lnk->link_idx].sgl, sg, nents, i) { + size = min_t(int, PAGE_SIZE - offset, buf_size); + sg_set_page(sg, vmalloc_to_page(buf), size, offset); + buf += size / sizeof(*buf); + buf_size -= size; + offset = 0; + } + } else { + /* physically contiguous buffer */ + sg_set_buf(buf_desc->sgt[lnk->link_idx].sgl, + buf_desc->cpu_addr, buf_desc->len); + } + + /* map sg table to DMA address */ + rc = smc_ib_buf_map_sg(lnk, buf_desc, + is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE); + /* SMC protocol depends on mapping to one DMA address only */ + if (rc != nents) { + rc = -EAGAIN; + goto free_table; + } + + buf_desc->is_dma_need_sync |= + smc_ib_is_sg_need_sync(lnk, buf_desc) << lnk->link_idx; + + if (is_rmb || buf_desc->is_vm) { + /* create a new memory region for the RMB or vzalloced sndbuf */ + access_flags = is_rmb ? + IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE : + IB_ACCESS_LOCAL_WRITE; + + rc = smc_ib_get_memory_region(lnk->roce_pd, access_flags, + buf_desc, lnk->link_idx); + if (rc) + goto buf_unmap; + smc_ib_sync_sg_for_device(lnk, buf_desc, + is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE); + } + buf_desc->is_map_ib[lnk->link_idx] = true; + return 0; + +buf_unmap: + smc_ib_buf_unmap_sg(lnk, buf_desc, + is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE); +free_table: + sg_free_table(&buf_desc->sgt[lnk->link_idx]); + return rc; +} + +/* register a new buf on IB device, rmb or vzalloced sndbuf + * must be called under lgr->llc_conf_mutex lock + */ +int smcr_link_reg_buf(struct smc_link *link, struct smc_buf_desc *buf_desc) +{ + if (list_empty(&link->lgr->list)) + return -ENOLINK; + if (!buf_desc->is_reg_mr[link->link_idx]) { + /* register memory region for new buf */ + if (buf_desc->is_vm) + buf_desc->mr[link->link_idx]->iova = + (uintptr_t)buf_desc->cpu_addr; + if (smc_wr_reg_send(link, buf_desc->mr[link->link_idx])) { + buf_desc->is_reg_err = true; + return -EFAULT; + } + buf_desc->is_reg_mr[link->link_idx] = true; + } + return 0; +} + +static int _smcr_buf_map_lgr(struct smc_link *lnk, struct rw_semaphore *lock, + struct list_head *lst, bool is_rmb) +{ + struct smc_buf_desc *buf_desc, *bf; + int rc = 0; + + down_write(lock); + list_for_each_entry_safe(buf_desc, bf, lst, list) { + if (!buf_desc->used) + continue; + rc = smcr_buf_map_link(buf_desc, is_rmb, lnk); + if (rc) + goto out; + } +out: + up_write(lock); + return rc; +} + +/* map all used buffers of lgr for a new link */ +int smcr_buf_map_lgr(struct smc_link *lnk) +{ + struct smc_link_group *lgr = lnk->lgr; + int i, rc = 0; + + for (i = 0; i < SMC_RMBE_SIZES; i++) { + rc = _smcr_buf_map_lgr(lnk, &lgr->rmbs_lock, + &lgr->rmbs[i], true); + if (rc) + return rc; + rc = _smcr_buf_map_lgr(lnk, &lgr->sndbufs_lock, + &lgr->sndbufs[i], false); + if (rc) + return rc; + } + return 0; +} + +/* register all used buffers of lgr for a new link, + * must be called under lgr->llc_conf_mutex lock + */ +int smcr_buf_reg_lgr(struct smc_link *lnk) +{ + struct smc_link_group *lgr = lnk->lgr; + struct smc_buf_desc *buf_desc, *bf; + int i, rc = 0; + + /* reg all RMBs for a new link */ + down_write(&lgr->rmbs_lock); + for (i = 0; i < SMC_RMBE_SIZES; i++) { + list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) { + if (!buf_desc->used) + continue; + rc = smcr_link_reg_buf(lnk, buf_desc); + if (rc) { + up_write(&lgr->rmbs_lock); + return rc; + } + } + } + up_write(&lgr->rmbs_lock); + + if (lgr->buf_type == SMCR_PHYS_CONT_BUFS) + return rc; + + /* reg all vzalloced sndbufs for a new link */ + down_write(&lgr->sndbufs_lock); + for (i = 0; i < SMC_RMBE_SIZES; i++) { + list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i], list) { + if (!buf_desc->used || !buf_desc->is_vm) + continue; + rc = smcr_link_reg_buf(lnk, buf_desc); + if (rc) { + up_write(&lgr->sndbufs_lock); + return rc; + } + } + } + up_write(&lgr->sndbufs_lock); + return rc; +} + +static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr, + bool is_rmb, int bufsize) +{ + struct smc_buf_desc *buf_desc; + + /* try to alloc a new buffer */ + buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL); + if (!buf_desc) + return ERR_PTR(-ENOMEM); + + switch (lgr->buf_type) { + case SMCR_PHYS_CONT_BUFS: + case SMCR_MIXED_BUFS: + buf_desc->order = get_order(bufsize); + buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN | + __GFP_NOMEMALLOC | __GFP_COMP | + __GFP_NORETRY | __GFP_ZERO, + buf_desc->order); + if (buf_desc->pages) { + buf_desc->cpu_addr = + (void *)page_address(buf_desc->pages); + buf_desc->len = bufsize; + buf_desc->is_vm = false; + break; + } + if (lgr->buf_type == SMCR_PHYS_CONT_BUFS) + goto out; + fallthrough; // try virtually continguous buf + case SMCR_VIRT_CONT_BUFS: + buf_desc->order = get_order(bufsize); + buf_desc->cpu_addr = vzalloc(PAGE_SIZE << buf_desc->order); + if (!buf_desc->cpu_addr) + goto out; + buf_desc->pages = NULL; + buf_desc->len = bufsize; + buf_desc->is_vm = true; + break; + } + return buf_desc; + +out: + kfree(buf_desc); + return ERR_PTR(-EAGAIN); +} + +/* map buf_desc on all usable links, + * unused buffers stay mapped as long as the link is up + */ +static int smcr_buf_map_usable_links(struct smc_link_group *lgr, + struct smc_buf_desc *buf_desc, bool is_rmb) +{ + int i, rc = 0, cnt = 0; + + /* protect against parallel link reconfiguration */ + down_read(&lgr->llc_conf_mutex); + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + struct smc_link *lnk = &lgr->lnk[i]; + + if (!smc_link_usable(lnk)) + continue; + if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) { + rc = -ENOMEM; + goto out; + } + cnt++; + } +out: + up_read(&lgr->llc_conf_mutex); + if (!rc && !cnt) + rc = -EINVAL; + return rc; +} + +static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr, + bool is_dmb, int bufsize) +{ + struct smc_buf_desc *buf_desc; + int rc; + + /* try to alloc a new DMB */ + buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL); + if (!buf_desc) + return ERR_PTR(-ENOMEM); + if (is_dmb) { + rc = smc_ism_register_dmb(lgr, bufsize, buf_desc); + if (rc) { + kfree(buf_desc); + if (rc == -ENOMEM) + return ERR_PTR(-EAGAIN); + if (rc == -ENOSPC) + return ERR_PTR(-ENOSPC); + return ERR_PTR(-EIO); + } + buf_desc->pages = virt_to_page(buf_desc->cpu_addr); + /* CDC header stored in buf. So, pretend it was smaller */ + buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg); + } else { + buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL | + __GFP_NOWARN | __GFP_NORETRY | + __GFP_NOMEMALLOC); + if (!buf_desc->cpu_addr) { + kfree(buf_desc); + return ERR_PTR(-EAGAIN); + } + buf_desc->len = bufsize; + } + return buf_desc; +} + +static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb) +{ + struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM); + struct smc_connection *conn = &smc->conn; + struct smc_link_group *lgr = conn->lgr; + struct list_head *buf_list; + int bufsize, bufsize_comp; + struct rw_semaphore *lock; /* lock buffer list */ + bool is_dgraded = false; + + if (is_rmb) + /* use socket recv buffer size (w/o overhead) as start value */ + bufsize = smc->sk.sk_rcvbuf / 2; + else + /* use socket send buffer size (w/o overhead) as start value */ + bufsize = smc->sk.sk_sndbuf / 2; + + for (bufsize_comp = smc_compress_bufsize(bufsize, is_smcd, is_rmb); + bufsize_comp >= 0; bufsize_comp--) { + if (is_rmb) { + lock = &lgr->rmbs_lock; + buf_list = &lgr->rmbs[bufsize_comp]; + } else { + lock = &lgr->sndbufs_lock; + buf_list = &lgr->sndbufs[bufsize_comp]; + } + bufsize = smc_uncompress_bufsize(bufsize_comp); + + /* check for reusable slot in the link group */ + buf_desc = smc_buf_get_slot(bufsize_comp, lock, buf_list); + if (buf_desc) { + buf_desc->is_dma_need_sync = 0; + SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize); + SMC_STAT_BUF_REUSE(smc, is_smcd, is_rmb); + break; /* found reusable slot */ + } + + if (is_smcd) + buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize); + else + buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize); + + if (PTR_ERR(buf_desc) == -ENOMEM) + break; + if (IS_ERR(buf_desc)) { + if (!is_dgraded) { + is_dgraded = true; + SMC_STAT_RMB_DOWNGRADED(smc, is_smcd, is_rmb); + } + continue; + } + + SMC_STAT_RMB_ALLOC(smc, is_smcd, is_rmb); + SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize); + buf_desc->used = 1; + down_write(lock); + list_add(&buf_desc->list, buf_list); + up_write(lock); + break; /* found */ + } + + if (IS_ERR(buf_desc)) + return PTR_ERR(buf_desc); + + if (!is_smcd) { + if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) { + smcr_buf_unuse(buf_desc, is_rmb, lgr); + return -ENOMEM; + } + } + + if (is_rmb) { + conn->rmb_desc = buf_desc; + conn->rmbe_size_comp = bufsize_comp; + smc->sk.sk_rcvbuf = bufsize * 2; + atomic_set(&conn->bytes_to_rcv, 0); + conn->rmbe_update_limit = + smc_rmb_wnd_update_limit(buf_desc->len); + if (is_smcd) + smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */ + } else { + conn->sndbuf_desc = buf_desc; + smc->sk.sk_sndbuf = bufsize * 2; + atomic_set(&conn->sndbuf_space, bufsize); + } + return 0; +} + +void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn) +{ + if (!conn->sndbuf_desc->is_dma_need_sync) + return; + if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd || + !smc_link_active(conn->lnk)) + return; + smc_ib_sync_sg_for_device(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE); +} + +void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn) +{ + int i; + + if (!conn->rmb_desc->is_dma_need_sync) + return; + if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd) + return; + for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) { + if (!smc_link_active(&conn->lgr->lnk[i])) + continue; + smc_ib_sync_sg_for_cpu(&conn->lgr->lnk[i], conn->rmb_desc, + DMA_FROM_DEVICE); + } +} + +/* create the send and receive buffer for an SMC socket; + * receive buffers are called RMBs; + * (even though the SMC protocol allows more than one RMB-element per RMB, + * the Linux implementation uses just one RMB-element per RMB, i.e. uses an + * extra RMB for every connection in a link group + */ +int smc_buf_create(struct smc_sock *smc, bool is_smcd) +{ + int rc; + + /* create send buffer */ + rc = __smc_buf_create(smc, is_smcd, false); + if (rc) + return rc; + /* create rmb */ + rc = __smc_buf_create(smc, is_smcd, true); + if (rc) { + down_write(&smc->conn.lgr->sndbufs_lock); + list_del(&smc->conn.sndbuf_desc->list); + up_write(&smc->conn.lgr->sndbufs_lock); + smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc); + smc->conn.sndbuf_desc = NULL; + } + return rc; +} + +static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr) +{ + int i; + + for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) { + if (!test_and_set_bit(i, lgr->rtokens_used_mask)) + return i; + } + return -ENOSPC; +} + +static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx, + u32 rkey) +{ + int i; + + for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) { + if (test_bit(i, lgr->rtokens_used_mask) && + lgr->rtokens[i][lnk_idx].rkey == rkey) + return i; + } + return -ENOENT; +} + +/* set rtoken for a new link to an existing rmb */ +void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new, + __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey) +{ + int rtok_idx; + + rtok_idx = smc_rtoken_find_by_link(lgr, link_idx, ntohl(nw_rkey_known)); + if (rtok_idx == -ENOENT) + return; + lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey); + lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr); +} + +/* set rtoken for a new link whose link_id is given */ +void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id, + __be64 nw_vaddr, __be32 nw_rkey) +{ + u64 dma_addr = be64_to_cpu(nw_vaddr); + u32 rkey = ntohl(nw_rkey); + bool found = false; + int link_idx; + + for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) { + if (lgr->lnk[link_idx].link_id == link_id) { + found = true; + break; + } + } + if (!found) + return; + lgr->rtokens[rtok_idx][link_idx].rkey = rkey; + lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr; +} + +/* add a new rtoken from peer */ +int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey) +{ + struct smc_link_group *lgr = smc_get_lgr(lnk); + u64 dma_addr = be64_to_cpu(nw_vaddr); + u32 rkey = ntohl(nw_rkey); + int i; + + for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) { + if (lgr->rtokens[i][lnk->link_idx].rkey == rkey && + lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr && + test_bit(i, lgr->rtokens_used_mask)) { + /* already in list */ + return i; + } + } + i = smc_rmb_reserve_rtoken_idx(lgr); + if (i < 0) + return i; + lgr->rtokens[i][lnk->link_idx].rkey = rkey; + lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr; + return i; +} + +/* delete an rtoken from all links */ +int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey) +{ + struct smc_link_group *lgr = smc_get_lgr(lnk); + u32 rkey = ntohl(nw_rkey); + int i, j; + + for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) { + if (lgr->rtokens[i][lnk->link_idx].rkey == rkey && + test_bit(i, lgr->rtokens_used_mask)) { + for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) { + lgr->rtokens[i][j].rkey = 0; + lgr->rtokens[i][j].dma_addr = 0; + } + clear_bit(i, lgr->rtokens_used_mask); + return 0; + } + } + return -ENOENT; +} + +/* save rkey and dma_addr received from peer during clc handshake */ +int smc_rmb_rtoken_handling(struct smc_connection *conn, + struct smc_link *lnk, + struct smc_clc_msg_accept_confirm *clc) +{ + conn->rtoken_idx = smc_rtoken_add(lnk, clc->r0.rmb_dma_addr, + clc->r0.rmb_rkey); + if (conn->rtoken_idx < 0) + return conn->rtoken_idx; + return 0; +} + +static void smc_core_going_away(void) +{ + struct smc_ib_device *smcibdev; + struct smcd_dev *smcd; + + mutex_lock(&smc_ib_devices.mutex); + list_for_each_entry(smcibdev, &smc_ib_devices.list, list) { + int i; + + for (i = 0; i < SMC_MAX_PORTS; i++) + set_bit(i, smcibdev->ports_going_away); + } + mutex_unlock(&smc_ib_devices.mutex); + + mutex_lock(&smcd_dev_list.mutex); + list_for_each_entry(smcd, &smcd_dev_list.list, list) { + smcd->going_away = 1; + } + mutex_unlock(&smcd_dev_list.mutex); +} + +/* Clean up all SMC link groups */ +static void smc_lgrs_shutdown(void) +{ + struct smcd_dev *smcd; + + smc_core_going_away(); + + smc_smcr_terminate_all(NULL); + + mutex_lock(&smcd_dev_list.mutex); + list_for_each_entry(smcd, &smcd_dev_list.list, list) + smc_smcd_terminate_all(smcd); + mutex_unlock(&smcd_dev_list.mutex); +} + +static int smc_core_reboot_event(struct notifier_block *this, + unsigned long event, void *ptr) +{ + smc_lgrs_shutdown(); + smc_ib_unregister_client(); + smc_ism_exit(); + return 0; +} + +static struct notifier_block smc_reboot_notifier = { + .notifier_call = smc_core_reboot_event, +}; + +int __init smc_core_init(void) +{ + return register_reboot_notifier(&smc_reboot_notifier); +} + +/* Called (from smc_exit) when module is removed */ +void smc_core_exit(void) +{ + unregister_reboot_notifier(&smc_reboot_notifier); + smc_lgrs_shutdown(); +} |