linux/net/smc/smc_core.c
Karsten Graul 72b7f6c487 net/smc: unique reason code for exceeded max dmb count
When the maximum dmb buffer limit for an ism device is reached no more
dmb buffers can be registered. When this happens the reason code is set
to SMC_CLC_DECL_MEM indicating out-of-memory. This is the same reason
code that is used when no memory could be allocated for the new dmb
buffer.
This is confusing for users when they see this error but there is more
memory available. To solve this set a separate new reason code when the
maximum dmb limit exceeded.

Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-27 10:30:01 -07:00

1958 lines
51 KiB
C

// 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 <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"
#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)
#define SMC_LGR_FREE_DELAY_FAST (8 * HZ)
static 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_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 && !lgr->freefast) {
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);
}
}
void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr)
{
if (!lgr->freeing && !lgr->freefast) {
lgr->freefast = 1;
mod_delayed_work(system_wq, &lgr->free_work,
SMC_LGR_FREE_DELAY_FAST);
}
}
/* 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 */
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;
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)
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);
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 (!lgr)
return;
write_lock_bh(&lgr->conns_lock);
if (conn->alert_token_local) {
__smc_lgr_unregister_conn(conn);
}
write_unlock_bh(&lgr->conns_lock);
conn->lgr = NULL;
}
void smc_lgr_cleanup_early(struct smc_connection *conn)
{
struct smc_link_group *lgr = conn->lgr;
struct list_head *lgr_list;
spinlock_t *lgr_lock;
if (!lgr)
return;
smc_conn_free(conn);
lgr_list = 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_schedule_free_work_fast(lgr);
}
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_usable(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) {
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)
continue;
}
break;
}
return link_id;
}
int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
u8 link_idx, struct smc_init_info *ini)
{
u8 rndvec[3];
int rc;
get_device(&ini->ib_dev->ibdev->dev);
atomic_inc(&ini->ib_dev->lnk_cnt);
lnk->link_id = smcr_next_link_id(lgr);
lnk->lgr = lgr;
lnk->link_idx = link_idx;
lnk->smcibdev = ini->ib_dev;
lnk->ibport = ini->ib_port;
lnk->path_mtu = ini->ib_dev->pattr[ini->ib_port - 1].active_mtu;
smc_llc_link_set_uid(lnk);
INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
if (!ini->ib_dev->initialized) {
rc = (int)smc_ib_setup_per_ibdev(ini->ib_dev);
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);
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:
put_device(&ini->ib_dev->ibdev->dev);
memset(lnk, 0, sizeof(struct smc_link));
lnk->state = SMC_LNK_UNUSED;
if (!atomic_dec_return(&ini->ib_dev->lnk_cnt))
wake_up(&ini->ib_dev->lnks_deleted);
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 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->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->is_smcd = ini->is_smcd;
lgr->sync_err = 0;
lgr->terminating = 0;
lgr->freefast = 0;
lgr->freeing = 0;
lgr->vlan_id = ini->vlan_id;
mutex_init(&lgr->sndbufs_lock);
mutex_init(&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 */
get_device(&ini->ism_dev->dev);
lgr->peer_gid = ini->ism_gid;
lgr->smcd = ini->ism_dev;
lgr_list = &ini->ism_dev->lgr_list;
lgr_lock = &lgr->smcd->lgr_lock;
lgr->peer_shutdown = 0;
atomic_inc(&ini->ism_dev->lgr_cnt);
} else {
/* SMC-R specific settings */
lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
memcpy(lgr->peer_systemid, ini->ib_lcl->id_for_peer,
SMC_SYSTEMID_LEN);
memcpy(lgr->pnet_id, ini->ib_dev->pnetid[ini->ib_port - 1],
SMC_MAX_PNETID_LEN);
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)
goto free_lgr;
lgr_list = &smc_lgr_list.list;
lgr_lock = &smc_lgr_list.lock;
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_lgr:
kfree(lgr);
ism_put_vlan:
if (ini->is_smcd && ini->vlan_id)
smc_ism_put_vlan(ini->ism_dev, 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) {
schedule_delayed_work(&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;
}
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_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);
conn->lnk = 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) {
smcr_link_down_cond_sched(to_lnk);
return NULL;
}
/* avoid race with smcr_tx_sndbuf_nonempty() */
spin_lock_bh(&conn->send_lock);
conn->lnk = to_lnk;
rc = smc_switch_cursor(smc, pend, wr_buf);
spin_unlock_bh(&conn->send_lock);
sock_put(&smc->sk);
if (rc) {
smcr_link_down_cond_sched(to_lnk);
return NULL;
}
goto again;
}
read_unlock_bh(&lgr->conns_lock);
return to_lnk;
}
static void smcr_buf_unuse(struct smc_buf_desc *rmb_desc,
struct smc_link_group *lgr)
{
int rc;
if (rmb_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() */
mutex_lock(&lgr->llc_conf_mutex);
smc_llc_do_delete_rkey(lgr, rmb_desc);
rmb_desc->is_conf_rkey = false;
mutex_unlock(&lgr->llc_conf_mutex);
smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
}
}
if (rmb_desc->is_reg_err) {
/* buf registration failed, reuse not possible */
mutex_lock(&lgr->rmbs_lock);
list_del(&rmb_desc->list);
mutex_unlock(&lgr->rmbs_lock);
smc_buf_free(lgr, true, rmb_desc);
} else {
rmb_desc->used = 0;
}
}
static void smc_buf_unuse(struct smc_connection *conn,
struct smc_link_group *lgr)
{
if (conn->sndbuf_desc)
conn->sndbuf_desc->used = 0;
if (conn->rmb_desc && lgr->is_smcd)
conn->rmb_desc->used = 0;
else if (conn->rmb_desc)
smcr_buf_unuse(conn->rmb_desc, lgr);
}
/* 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)
return;
if (lgr->is_smcd) {
if (!list_empty(&lgr->list))
smc_ism_unset_conn(conn);
tasklet_kill(&conn->rx_tsklet);
} else {
smc_cdc_tx_dismiss_slots(conn);
if (current_work() != &conn->abort_work)
cancel_work_sync(&conn->abort_work);
}
if (!list_empty(&lgr->list)) {
smc_lgr_unregister_conn(conn);
smc_buf_unuse(conn, lgr); /* allow buffer reuse */
}
if (!lgr->conns_num)
smc_lgr_schedule_free_work(lgr);
}
/* 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_reg_mr[lnk->link_idx] = false;
if (!buf_desc->is_map_ib[lnk->link_idx])
return;
if (is_rmb) {
if (buf_desc->mr_rx[lnk->link_idx]) {
smc_ib_put_memory_region(
buf_desc->mr_rx[lnk->link_idx]);
buf_desc->mr_rx[lnk->link_idx] = NULL;
}
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++) {
mutex_lock(&lgr->rmbs_lock);
list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
smcr_buf_unmap_link(buf_desc, true, lnk);
mutex_unlock(&lgr->rmbs_lock);
mutex_lock(&lgr->sndbufs_lock);
list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
list)
smcr_buf_unmap_link(buf_desc, false, lnk);
mutex_unlock(&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;
}
}
/* must be called under lgr->llc_conf_mutex lock */
void smcr_link_clear(struct smc_link *lnk, bool log)
{
struct smc_ib_device *smcibdev;
if (!lnk->lgr || lnk->state == SMC_LNK_UNUSED)
return;
lnk->peer_qpn = 0;
smc_llc_link_clear(lnk, log);
smcr_buf_unmap_lgr(lnk);
smcr_rtoken_clear_link(lnk);
smc_ib_modify_qp_reset(lnk);
smc_wr_free_link(lnk);
smc_ib_destroy_queue_pair(lnk);
smc_ib_dealloc_protection_domain(lnk);
smc_wr_free_link_mem(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);
}
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->pages)
__free_pages(buf_desc->pages, buf_desc->order);
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);
}
/* remove a link group */
static void smc_lgr_free(struct smc_link_group *lgr)
{
int i;
if (!lgr->is_smcd) {
mutex_lock(&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);
}
mutex_unlock(&lgr->llc_conf_mutex);
smc_llc_lgr_clear(lgr);
}
smc_lgr_free_bufs(lgr);
if (lgr->is_smcd) {
if (!lgr->terminating) {
smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
put_device(&lgr->smcd->dev);
}
if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
wake_up(&lgr->smcd->lgrs_deleted);
} else {
if (!atomic_dec_return(&lgr_cnt))
wake_up(&lgrs_deleted);
}
kfree(lgr);
}
static void smcd_unregister_all_dmbs(struct smc_link_group *lgr)
{
int i;
for (i = 0; i < SMC_RMBE_SIZES; i++) {
struct smc_buf_desc *buf_desc;
list_for_each_entry(buf_desc, &lgr->rmbs[i], list) {
buf_desc->len += sizeof(struct smcd_cdc_msg);
smc_ism_unregister_dmb(lgr->smcd, buf_desc);
}
}
}
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_tx_dismiss_slots(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);
smcd_unregister_all_dmbs(lgr);
smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
put_device(&lgr->smcd->dev);
} 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_sync(&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 state changed: "
"%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
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);
smc_conn_kill(conn, true);
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;
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)
continue;
/* trigger local add link processing */
link = smc_llc_usable_link(lgr);
if (link)
smc_llc_add_link_local(link);
}
}
/* 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;
smc_ib_modify_qp_reset(lnk);
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 */
mutex_unlock(&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);
mutex_lock(&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))
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))
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);
mutex_lock(&lgr->llc_conf_mutex);
smcr_link_down(link);
mutex_unlock(&lgr->llc_conf_mutex);
}
/* Determine vlan of internal TCP socket.
* @vlan_id: address to store the determined vlan id into
*/
int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
{
struct dst_entry *dst = sk_dst_get(clcsock->sk);
struct net_device *ndev;
int i, nest_lvl, 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;
}
rtnl_lock();
nest_lvl = ndev->lower_level;
for (i = 0; i < nest_lvl; i++) {
struct list_head *lower = &ndev->adj_list.lower;
if (list_empty(lower))
break;
lower = lower->next;
ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower);
if (is_vlan_dev(ndev)) {
ini->vlan_id = vlan_dev_vlan_id(ndev);
break;
}
}
rtnl_unlock();
out_rel:
dst_release(dst);
out:
return rc;
}
static bool smcr_lgr_match(struct smc_link_group *lgr,
struct smc_clc_msg_local *lcl,
enum smc_lgr_role role, u32 clcqpn)
{
int i;
if (memcmp(lgr->peer_systemid, lcl->id_for_peer, SMC_SYSTEMID_LEN) ||
lgr->role != role)
return false;
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
if (!smc_link_active(&lgr->lnk[i]))
continue;
if ((lgr->role == SMC_SERV || lgr->lnk[i].peer_qpn == clcqpn) &&
!memcmp(lgr->lnk[i].peer_gid, &lcl->gid, SMC_GID_SIZE) &&
!memcmp(lgr->lnk[i].peer_mac, lcl->mac, sizeof(lcl->mac)))
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 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->lgr_list : &smc_lgr_list.list;
lgr_lock = ini->is_smcd ? &ini->ism_dev->lgr_lock : &smc_lgr_list.lock;
ini->cln_first_contact = SMC_FIRST_CONTACT;
role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
if (role == SMC_CLNT && ini->srv_first_contact)
/* 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_gid) :
smcr_lgr_match(lgr, ini->ib_lcl, role, ini->ib_clcqpn)) &&
!lgr->sync_err &&
lgr->vlan_id == ini->vlan_id &&
(role == SMC_CLNT || ini->is_smcd ||
lgr->conns_num < SMC_RMBS_PER_LGR_MAX)) {
/* link group found */
ini->cln_first_contact = SMC_REUSE_CONTACT;
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->srv_first_contact &&
ini->cln_first_contact == SMC_FIRST_CONTACT) {
/* 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->cln_first_contact == SMC_FIRST_CONTACT) {
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)
goto out;
}
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_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 */
}
#ifndef KERNEL_HAS_ATOMIC64
spin_lock_init(&conn->acurs_lock);
#endif
out:
return rc;
}
/* convert the RMB size into the compressed notation - minimum 16K.
* 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)
{
u8 compressed;
if (size <= SMC_BUF_MIN_SIZE)
return 0;
size = (size - 1) >> 14;
compressed = ilog2(size) + 1;
if (compressed >= SMC_RMBE_SIZES)
compressed = SMC_RMBE_SIZES - 1;
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 mutex *lock,
struct list_head *buf_list)
{
struct smc_buf_desc *buf_slot;
mutex_lock(lock);
list_for_each_entry(buf_slot, buf_list, list) {
if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
mutex_unlock(lock);
return buf_slot;
}
}
mutex_unlock(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 min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
}
/* map an rmb 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;
if (buf_desc->is_map_ib[lnk->link_idx])
return 0;
rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], 1, GFP_KERNEL);
if (rc)
return rc;
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 != 1) {
rc = -EAGAIN;
goto free_table;
}
/* create a new memory region for the RMB */
if (is_rmb) {
rc = smc_ib_get_memory_region(lnk->roce_pd,
IB_ACCESS_REMOTE_WRITE |
IB_ACCESS_LOCAL_WRITE,
buf_desc, lnk->link_idx);
if (rc)
goto buf_unmap;
smc_ib_sync_sg_for_device(lnk, buf_desc, DMA_FROM_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 rmb on IB device,
* must be called under lgr->llc_conf_mutex lock
*/
int smcr_link_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc)
{
if (list_empty(&link->lgr->list))
return -ENOLINK;
if (!rmb_desc->is_reg_mr[link->link_idx]) {
/* register memory region for new rmb */
if (smc_wr_reg_send(link, rmb_desc->mr_rx[link->link_idx])) {
rmb_desc->is_reg_err = true;
return -EFAULT;
}
rmb_desc->is_reg_mr[link->link_idx] = true;
}
return 0;
}
static int _smcr_buf_map_lgr(struct smc_link *lnk, struct mutex *lock,
struct list_head *lst, bool is_rmb)
{
struct smc_buf_desc *buf_desc, *bf;
int rc = 0;
mutex_lock(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:
mutex_unlock(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;
mutex_lock(&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_rmb(lnk, buf_desc);
if (rc)
goto out;
}
}
out:
mutex_unlock(&lgr->rmbs_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);
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) {
kfree(buf_desc);
return ERR_PTR(-EAGAIN);
}
buf_desc->cpu_addr = (void *)page_address(buf_desc->pages);
buf_desc->len = bufsize;
return buf_desc;
}
/* 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;
/* protect against parallel link reconfiguration */
mutex_lock(&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;
}
}
out:
mutex_unlock(&lgr->llc_conf_mutex);
return rc;
}
#define SMCD_DMBE_SIZES 7 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
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;
if (smc_compress_bufsize(bufsize) > SMCD_DMBE_SIZES)
return ERR_PTR(-EAGAIN);
/* 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);
return (rc == -ENOMEM) ? ERR_PTR(-EAGAIN) : ERR_PTR(rc);
}
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_short;
struct mutex *lock; /* lock buffer list */
int sk_buf_size;
if (is_rmb)
/* use socket recv buffer size (w/o overhead) as start value */
sk_buf_size = smc->sk.sk_rcvbuf / 2;
else
/* use socket send buffer size (w/o overhead) as start value */
sk_buf_size = smc->sk.sk_sndbuf / 2;
for (bufsize_short = smc_compress_bufsize(sk_buf_size);
bufsize_short >= 0; bufsize_short--) {
if (is_rmb) {
lock = &lgr->rmbs_lock;
buf_list = &lgr->rmbs[bufsize_short];
} else {
lock = &lgr->sndbufs_lock;
buf_list = &lgr->sndbufs[bufsize_short];
}
bufsize = smc_uncompress_bufsize(bufsize_short);
if ((1 << get_order(bufsize)) > SG_MAX_SINGLE_ALLOC)
continue;
/* check for reusable slot in the link group */
buf_desc = smc_buf_get_slot(bufsize_short, lock, buf_list);
if (buf_desc) {
memset(buf_desc->cpu_addr, 0, bufsize);
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))
continue;
buf_desc->used = 1;
mutex_lock(lock);
list_add(&buf_desc->list, buf_list);
mutex_unlock(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, lgr);
return -ENOMEM;
}
}
if (is_rmb) {
conn->rmb_desc = buf_desc;
conn->rmbe_size_short = bufsize_short;
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_cpu(struct smc_connection *conn)
{
if (!conn->lgr || conn->lgr->is_smcd || !smc_link_active(conn->lnk))
return;
smc_ib_sync_sg_for_cpu(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
}
void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
{
if (!conn->lgr || 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->lgr || 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);
}
}
void smc_rmb_sync_sg_for_device(struct smc_connection *conn)
{
int i;
if (!conn->lgr || 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_device(&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) {
mutex_lock(&smc->conn.lgr->sndbufs_lock);
list_del(&smc->conn.sndbuf_desc->list);
mutex_unlock(&smc->conn.lgr->sndbufs_lock);
smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
}
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->rmb_dma_addr,
clc->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();
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();
}