// SPDX-License-Identifier: GPL-2.0
/* Shared Memory Communications Direct over ISM devices (SMC-D)
*
* Functions for ISM device.
*
* Copyright IBM Corp. 2018
*/
#include <linux/if_vlan.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <asm/page.h>
#include "smc.h"
#include "smc_core.h"
#include "smc_ism.h"
#include "smc_pnet.h"
#include "smc_netlink.h"
#include "linux/ism.h"
struct smcd_dev_list smcd_dev_list = {
.list = LIST_HEAD_INIT(smcd_dev_list.list),
.mutex = __MUTEX_INITIALIZER(smcd_dev_list.mutex)
};
static bool smc_ism_v2_capable;
static u8 smc_ism_v2_system_eid[SMC_MAX_EID_LEN];
#if IS_ENABLED(CONFIG_ISM)
static void smcd_register_dev(struct ism_dev *ism);
static void smcd_unregister_dev(struct ism_dev *ism);
static void smcd_handle_event(struct ism_dev *ism, struct ism_event *event);
static void smcd_handle_irq(struct ism_dev *ism, unsigned int dmbno,
u16 dmbemask);
static struct ism_client smc_ism_client = {
.name = "SMC-D",
.add = smcd_register_dev,
.remove = smcd_unregister_dev,
.handle_event = smcd_handle_event,
.handle_irq = smcd_handle_irq,
};
#endif
static void smc_ism_create_system_eid(void)
{
struct smc_ism_seid *seid =
(struct smc_ism_seid *)smc_ism_v2_system_eid;
#if IS_ENABLED(CONFIG_S390)
struct cpuid id;
u16 ident_tail;
char tmp[5];
memcpy(seid->seid_string, "IBM-SYSZ-ISMSEID00000000", 24);
get_cpu_id(&id);
ident_tail = (u16)(id.ident & SMC_ISM_IDENT_MASK);
snprintf(tmp, 5, "%04X", ident_tail);
memcpy(seid->serial_number, tmp, 4);
snprintf(tmp, 5, "%04X", id.machine);
memcpy(seid->type, tmp, 4);
#else
memset(seid, 0, SMC_MAX_EID_LEN);
#endif
}
/* Test if an ISM communication is possible - same CPC */
int smc_ism_cantalk(struct smcd_gid *peer_gid, unsigned short vlan_id,
struct smcd_dev *smcd)
{
return smcd->ops->query_remote_gid(smcd, peer_gid, vlan_id ? 1 : 0,
vlan_id);
}
void smc_ism_get_system_eid(u8 **eid)
{
if (!smc_ism_v2_capable)
*eid = NULL;
else
*eid = smc_ism_v2_system_eid;
}
u16 smc_ism_get_chid(struct smcd_dev *smcd)
{
return smcd->ops->get_chid(smcd);
}
/* HW supports ISM V2 and thus System EID is defined */
bool smc_ism_is_v2_capable(void)
{
return smc_ism_v2_capable;
}
void smc_ism_set_v2_capable(void)
{
smc_ism_v2_capable = true;
}
/* Set a connection using this DMBE. */
void smc_ism_set_conn(struct smc_connection *conn)
{
unsigned long flags;
spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = conn;
spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
}
/* Unset a connection using this DMBE. */
void smc_ism_unset_conn(struct smc_connection *conn)
{
unsigned long flags;
if (!conn->rmb_desc)
return;
spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = NULL;
spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
}
/* Register a VLAN identifier with the ISM device. Use a reference count
* and add a VLAN identifier only when the first DMB using this VLAN is
* registered.
*/
int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid)
{
struct smc_ism_vlanid *new_vlan, *vlan;
unsigned long flags;
int rc = 0;
if (!vlanid) /* No valid vlan id */
return -EINVAL;
if (!smcd->ops->add_vlan_id)
return -EOPNOTSUPP;
/* create new vlan entry, in case we need it */
new_vlan = kzalloc(sizeof(*new_vlan), GFP_KERNEL);
if (!new_vlan)
return -ENOMEM;
new_vlan->vlanid = vlanid;
refcount_set(&new_vlan->refcnt, 1);
/* if there is an existing entry, increase count and return */
spin_lock_irqsave(&smcd->lock, flags);
list_for_each_entry(vlan, &smcd->vlan, list) {
if (vlan->vlanid == vlanid) {
refcount_inc(&vlan->refcnt);
kfree(new_vlan);
goto out;
}
}
/* no existing entry found.
* add new entry to device; might fail, e.g., if HW limit reached
*/
if (smcd->ops->add_vlan_id(smcd, vlanid)) {
kfree(new_vlan);
rc = -EIO;
goto out;
}
list_add_tail(&new_vlan->list, &smcd->vlan);
out:
spin_unlock_irqrestore(&smcd->lock, flags);
return rc;
}
/* Unregister a VLAN identifier with the ISM device. Use a reference count
* and remove a VLAN identifier only when the last DMB using this VLAN is
* unregistered.
*/
int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid)
{
struct smc_ism_vlanid *vlan;
unsigned long flags;
bool found = false;
int rc = 0;
if (!vlanid) /* No valid vlan id */
return -EINVAL;
if (!smcd->ops->del_vlan_id)
return -EOPNOTSUPP;
spin_lock_irqsave(&smcd->lock, flags);
list_for_each_entry(vlan, &smcd->vlan, list) {
if (vlan->vlanid == vlanid) {
if (!refcount_dec_and_test(&vlan->refcnt))
goto out;
found = true;
break;
}
}
if (!found) {
rc = -ENOENT;
goto out; /* VLAN id not in table */
}
/* Found and the last reference just gone */
if (smcd->ops->del_vlan_id(smcd, vlanid))
rc = -EIO;
list_del(&vlan->list);
kfree(vlan);
out:
spin_unlock_irqrestore(&smcd->lock, flags);
return rc;
}
int smc_ism_unregister_dmb(struct smcd_dev *smcd, struct smc_buf_desc *dmb_desc)
{
struct smcd_dmb dmb;
int rc = 0;
if (!dmb_desc->dma_addr)
return rc;
memset(&dmb, 0, sizeof(dmb));
dmb.dmb_tok = dmb_desc->token;
dmb.sba_idx = dmb_desc->sba_idx;
dmb.cpu_addr = dmb_desc->cpu_addr;
dmb.dma_addr = dmb_desc->dma_addr;
dmb.dmb_len = dmb_desc->len;
rc = smcd->ops->unregister_dmb(smcd, &dmb);
if (!rc || rc == ISM_ERROR) {
dmb_desc->cpu_addr = NULL;
dmb_desc->dma_addr = 0;
}
return rc;
}
int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len,
struct smc_buf_desc *dmb_desc)
{
struct smcd_dmb dmb;
int rc;
memset(&dmb, 0, sizeof(dmb));
dmb.dmb_len = dmb_len;
dmb.sba_idx = dmb_desc->sba_idx;
dmb.vlan_id = lgr->vlan_id;
dmb.rgid = lgr->peer_gid.gid;
rc = lgr->smcd->ops->register_dmb(lgr->smcd, &dmb, lgr->smcd->client);
if (!rc) {
dmb_desc->sba_idx = dmb.sba_idx;
dmb_desc->token = dmb.dmb_tok;
dmb_desc->cpu_addr = dmb.cpu_addr;
dmb_desc->dma_addr = dmb.dma_addr;
dmb_desc->len = dmb.dmb_len;
}
return rc;
}
bool smc_ism_support_dmb_nocopy(struct smcd_dev *smcd)
{
/* for now only loopback-ism supports
* merging sndbuf with peer DMB to avoid
* data copies between them.
*/
return (smcd->ops->support_dmb_nocopy &&
smcd->ops->support_dmb_nocopy(smcd));
}
int smc_ism_attach_dmb(struct smcd_dev *dev, u64 token,
struct smc_buf_desc *dmb_desc)
{
struct smcd_dmb dmb;
int rc = 0;
if (!dev->ops->attach_dmb)
return -EINVAL;
memset(&dmb, 0, sizeof(dmb));
dmb.dmb_tok = token;
rc = dev->ops->attach_dmb(dev, &dmb);
if (!rc) {
dmb_desc->sba_idx = dmb.sba_idx;
dmb_desc->token = dmb.dmb_tok;
dmb_desc->cpu_addr = dmb.cpu_addr;
dmb_desc->dma_addr = dmb.dma_addr;
dmb_desc->len = dmb.dmb_len;
}
return rc;
}
int smc_ism_detach_dmb(struct smcd_dev *dev, u64 token)
{
if (!dev->ops->detach_dmb)
return -EINVAL;
return dev->ops->detach_dmb(dev, token);
}
static int smc_nl_handle_smcd_dev(struct smcd_dev *smcd,
struct sk_buff *skb,
struct netlink_callback *cb)
{
char smc_pnet[SMC_MAX_PNETID_LEN + 1];
struct smc_pci_dev smc_pci_dev;
struct nlattr *port_attrs;
struct nlattr *attrs;
struct ism_dev *ism;
int use_cnt = 0;
void *nlh;
ism = smcd->priv;
nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
&smc_gen_nl_family, NLM_F_MULTI,
SMC_NETLINK_GET_DEV_SMCD);
if (!nlh)
goto errmsg;
attrs = nla_nest_start(skb, SMC_GEN_DEV_SMCD);
if (!attrs)
goto errout;
use_cnt = atomic_read(&smcd->lgr_cnt);
if (nla_put_u32(skb, SMC_NLA_DEV_USE_CNT, use_cnt))
goto errattr;
if (nla_put_u8(skb, SMC_NLA_DEV_IS_CRIT, use_cnt > 0))
goto errattr;
memset(&smc_pci_dev, 0, sizeof(smc_pci_dev));
smc_set_pci_values(to_pci_dev(ism->dev.parent), &smc_pci_dev);
if (nla_put_u32(skb, SMC_NLA_DEV_PCI_FID, smc_pci_dev.pci_fid))
goto errattr;
if (nla_put_u16(skb, SMC_NLA_DEV_PCI_CHID, smc_pci_dev.pci_pchid))
goto errattr;
if (nla_put_u16(skb, SMC_NLA_DEV_PCI_VENDOR, smc_pci_dev.pci_vendor))
goto errattr;
if (nla_put_u16(skb, SMC_NLA_DEV_PCI_DEVICE, smc_pci_dev.pci_device))
goto errattr;
if (nla_put_string(skb, SMC_NLA_DEV_PCI_ID, smc_pci_dev.pci_id))
goto errattr;
port_attrs = nla_nest_start(skb, SMC_NLA_DEV_PORT);
if (!port_attrs)
goto errattr;
if (nla_put_u8(skb, SMC_NLA_DEV_PORT_PNET_USR, smcd->pnetid_by_user))
goto errportattr;
memcpy(smc_pnet, smcd->pnetid, SMC_MAX_PNETID_LEN);
smc_pnet[SMC_MAX_PNETID_LEN] = 0;
if (nla_put_string(skb, SMC_NLA_DEV_PORT_PNETID, smc_pnet))
goto errportattr;
nla_nest_end(skb, port_attrs);
nla_nest_end(skb, attrs);
genlmsg_end(skb, nlh);
return 0;
errportattr:
nla_nest_cancel(skb, port_attrs);
errattr:
nla_nest_cancel(skb, attrs);
errout:
nlmsg_cancel(skb, nlh);
errmsg:
return -EMSGSIZE;
}
static void smc_nl_prep_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);
int snum = cb_ctx->pos[0];
struct smcd_dev *smcd;
int num = 0;
mutex_lock(&dev_list->mutex);
list_for_each_entry(smcd, &dev_list->list, list) {
if (num < snum)
goto next;
if (smc_ism_is_loopback(smcd))
goto next;
if (smc_nl_handle_smcd_dev(smcd, skb, cb))
goto errout;
next:
num++;
}
errout:
mutex_unlock(&dev_list->mutex);
cb_ctx->pos[0] = num;
}
int smcd_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb)
{
smc_nl_prep_smcd_dev(&smcd_dev_list, skb, cb);
return skb->len;
}
#if IS_ENABLED(CONFIG_ISM)
struct smc_ism_event_work {
struct work_struct work;
struct smcd_dev *smcd;
struct ism_event event;
};
#define ISM_EVENT_REQUEST 0x0001
#define ISM_EVENT_RESPONSE 0x0002
#define ISM_EVENT_REQUEST_IR 0x00000001
#define ISM_EVENT_CODE_SHUTDOWN 0x80
#define ISM_EVENT_CODE_TESTLINK 0x83
union smcd_sw_event_info {
u64 info;
struct {
u8 uid[SMC_LGR_ID_SIZE];
unsigned short vlan_id;
u16 code;
};
};
static void smcd_handle_sw_event(struct smc_ism_event_work *wrk)
{
struct smcd_gid peer_gid = { .gid = wrk->event.tok,
.gid_ext = 0 };
union smcd_sw_event_info ev_info;
ev_info.info = wrk->event.info;
switch (wrk->event.code) {
case ISM_EVENT_CODE_SHUTDOWN: /* Peer shut down DMBs */
smc_smcd_terminate(wrk->smcd, &peer_gid, ev_info.vlan_id);
break;
case ISM_EVENT_CODE_TESTLINK: /* Activity timer */
if (ev_info.code == ISM_EVENT_REQUEST &&
wrk->smcd->ops->signal_event) {
ev_info.code = ISM_EVENT_RESPONSE;
wrk->smcd->ops->signal_event(wrk->smcd,
&peer_gid,
ISM_EVENT_REQUEST_IR,
ISM_EVENT_CODE_TESTLINK,
ev_info.info);
}
break;
}
}
/* worker for SMC-D events */
static void smc_ism_event_work(struct work_struct *work)
{
struct smc_ism_event_work *wrk =
container_of(work, struct smc_ism_event_work, work);
struct smcd_gid smcd_gid = { .gid = wrk->event.tok,
.gid_ext = 0 };
switch (wrk->event.type) {
case ISM_EVENT_GID: /* GID event, token is peer GID */
smc_smcd_terminate(wrk->smcd, &smcd_gid, VLAN_VID_MASK);
break;
case ISM_EVENT_DMB:
break;
case ISM_EVENT_SWR: /* Software defined event */
smcd_handle_sw_event(wrk);
break;
}
kfree(wrk);
}
static struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
const struct smcd_ops *ops, int max_dmbs)
{
struct smcd_dev *smcd;
smcd = devm_kzalloc(parent, sizeof(*smcd), GFP_KERNEL);
if (!smcd)
return NULL;
smcd->conn = devm_kcalloc(parent, max_dmbs,
sizeof(struct smc_connection *), GFP_KERNEL);
if (!smcd->conn)
return NULL;
smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
WQ_MEM_RECLAIM, name);
if (!smcd->event_wq)
return NULL;
smcd->ops = ops;
spin_lock_init(&smcd->lock);
spin_lock_init(&smcd->lgr_lock);
INIT_LIST_HEAD(&smcd->vlan);
INIT_LIST_HEAD(&smcd->lgr_list);
init_waitqueue_head(&smcd->lgrs_deleted);
return smcd;
}
static void smcd_register_dev(struct ism_dev *ism)
{
const struct smcd_ops *ops = ism_get_smcd_ops();
struct smcd_dev *smcd, *fentry;
if (!ops)
return;
smcd = smcd_alloc_dev(&ism->pdev->dev, dev_name(&ism->pdev->dev), ops,
ISM_NR_DMBS);
if (!smcd)
return;
smcd->priv = ism;
smcd->client = &smc_ism_client;
ism_set_priv(ism, &smc_ism_client, smcd);
if (smc_pnetid_by_dev_port(&ism->pdev->dev, 0, smcd->pnetid))
smc_pnetid_by_table_smcd(smcd);
if (smcd->ops->supports_v2())
smc_ism_set_v2_capable();
mutex_lock(&smcd_dev_list.mutex);
/* sort list:
* - devices without pnetid before devices with pnetid;
* - loopback-ism always at the very beginning;
*/
if (!smcd->pnetid[0]) {
fentry = list_first_entry_or_null(&smcd_dev_list.list,
struct smcd_dev, list);
if (fentry && smc_ism_is_loopback(fentry))
list_add(&smcd->list, &fentry->list);
else
list_add(&smcd->list, &smcd_dev_list.list);
} else {
list_add_tail(&smcd->list, &smcd_dev_list.list);
}
mutex_unlock(&smcd_dev_list.mutex);
pr_warn_ratelimited("smc: adding smcd device %s with pnetid %.16s%s\n",
dev_name(&ism->dev), smcd->pnetid,
smcd->pnetid_by_user ? " (user defined)" : "");
return;
}
static void smcd_unregister_dev(struct ism_dev *ism)
{
struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client);
pr_warn_ratelimited("smc: removing smcd device %s\n",
dev_name(&ism->dev));
smcd->going_away = 1;
smc_smcd_terminate_all(smcd);
mutex_lock(&smcd_dev_list.mutex);
list_del_init(&smcd->list);
mutex_unlock(&smcd_dev_list.mutex);
destroy_workqueue(smcd->event_wq);
}
/* SMCD Device event handler. Called from ISM device interrupt handler.
* Parameters are ism device pointer,
* - event->type (0 --> DMB, 1 --> GID),
* - event->code (event code),
* - event->tok (either DMB token when event type 0, or GID when event type 1)
* - event->time (time of day)
* - event->info (debug info).
*
* Context:
* - Function called in IRQ context from ISM device driver event handler.
*/
static void smcd_handle_event(struct ism_dev *ism, struct ism_event *event)
{
struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client);
struct smc_ism_event_work *wrk;
if (smcd->going_away)
return;
/* copy event to event work queue, and let it be handled there */
wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC);
if (!wrk)
return;
INIT_WORK(&wrk->work, smc_ism_event_work);
wrk->smcd = smcd;
wrk->event = *event;
queue_work(smcd->event_wq, &wrk->work);
}
/* SMCD Device interrupt handler. Called from ISM device interrupt handler.
* Parameters are the ism device pointer, DMB number, and the DMBE bitmask.
* Find the connection and schedule the tasklet for this connection.
*
* Context:
* - Function called in IRQ context from ISM device driver IRQ handler.
*/
static void smcd_handle_irq(struct ism_dev *ism, unsigned int dmbno,
u16 dmbemask)
{
struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client);
struct smc_connection *conn = NULL;
unsigned long flags;
spin_lock_irqsave(&smcd->lock, flags);
conn = smcd->conn[dmbno];
if (conn && !conn->killed)
tasklet_schedule(&conn->rx_tsklet);
spin_unlock_irqrestore(&smcd->lock, flags);
}
#endif
int smc_ism_signal_shutdown(struct smc_link_group *lgr)
{
int rc = 0;
#if IS_ENABLED(CONFIG_ISM)
union smcd_sw_event_info ev_info;
if (lgr->peer_shutdown)
return 0;
if (!lgr->smcd->ops->signal_event)
return 0;
memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE);
ev_info.vlan_id = lgr->vlan_id;
ev_info.code = ISM_EVENT_REQUEST;
rc = lgr->smcd->ops->signal_event(lgr->smcd, &lgr->peer_gid,
ISM_EVENT_REQUEST_IR,
ISM_EVENT_CODE_SHUTDOWN,
ev_info.info);
#endif
return rc;
}
int smc_ism_init(void)
{
int rc = 0;
smc_ism_v2_capable = false;
smc_ism_create_system_eid();
#if IS_ENABLED(CONFIG_ISM)
rc = ism_register_client(&smc_ism_client);
#endif
return rc;
}
void smc_ism_exit(void)
{
#if IS_ENABLED(CONFIG_ISM)
ism_unregister_client(&smc_ism_client);
#endif
}
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