--- /dev/null
+/*
+ * Shared Memory Communications over RDMA (SMC-R) and RoCE
+ *
+ * Generic netlink support functions to configure an SMC-R PNET table
+ *
+ * Copyright IBM Corp. 2016
+ *
+ * Author(s): Thomas Richter <tmricht@linux.vnet.ibm.com>
+ */
+
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/ctype.h>
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+#include <uapi/linux/if.h>
+#include <uapi/linux/smc.h>
+
+#include <rdma/ib_verbs.h>
+
+#include "smc_pnet.h"
+#include "smc_ib.h"
+
+#define SMC_MAX_PNET_ID_LEN 16 /* Max. length of PNET id */
+
+static struct nla_policy smc_pnet_policy[SMC_PNETID_MAX + 1] = {
+ [SMC_PNETID_NAME] = {
+ .type = NLA_NUL_STRING,
+ .len = SMC_MAX_PNET_ID_LEN - 1
+ },
+ [SMC_PNETID_ETHNAME] = {
+ .type = NLA_NUL_STRING,
+ .len = IFNAMSIZ - 1
+ },
+ [SMC_PNETID_IBNAME] = {
+ .type = NLA_NUL_STRING,
+ .len = IB_DEVICE_NAME_MAX - 1
+ },
+ [SMC_PNETID_IBPORT] = { .type = NLA_U8 }
+};
+
+static struct genl_family smc_pnet_nl_family;
+
+/**
+ * struct smc_pnettable - SMC PNET table anchor
+ * @lock: Lock for list action
+ * @pnetlist: List of PNETIDs
+ */
+static struct smc_pnettable {
+ rwlock_t lock;
+ struct list_head pnetlist;
+} smc_pnettable = {
+ .pnetlist = LIST_HEAD_INIT(smc_pnettable.pnetlist),
+ .lock = __RW_LOCK_UNLOCKED(smc_pnettable.lock)
+};
+
+/**
+ * struct smc_pnetentry - pnet identifier name entry
+ * @list: List node.
+ * @pnet_name: Pnet identifier name
+ * @ndev: pointer to network device.
+ * @smcibdev: Pointer to IB device.
+ */
+struct smc_pnetentry {
+ struct list_head list;
+ char pnet_name[SMC_MAX_PNET_ID_LEN + 1];
+ struct net_device *ndev;
+ struct smc_ib_device *smcibdev;
+ u8 ib_port;
+};
+
+/* Check if two RDMA device entries are identical. Use device name and port
+ * number for comparison.
+ */
+static bool smc_pnet_same_ibname(struct smc_pnetentry *pnetelem, char *ibname,
+ u8 ibport)
+{
+ return pnetelem->ib_port == ibport &&
+ !strncmp(pnetelem->smcibdev->ibdev->name, ibname,
+ sizeof(pnetelem->smcibdev->ibdev->name));
+}
+
+/* Find a pnetid in the pnet table.
+ */
+static struct smc_pnetentry *smc_pnet_find_pnetid(char *pnet_name)
+{
+ struct smc_pnetentry *pnetelem, *found_pnetelem = NULL;
+
+ read_lock(&smc_pnettable.lock);
+ list_for_each_entry(pnetelem, &smc_pnettable.pnetlist, list) {
+ if (!strncmp(pnetelem->pnet_name, pnet_name,
+ sizeof(pnetelem->pnet_name))) {
+ found_pnetelem = pnetelem;
+ break;
+ }
+ }
+ read_unlock(&smc_pnettable.lock);
+ return found_pnetelem;
+}
+
+/* Remove a pnetid from the pnet table.
+ */
+static int smc_pnet_remove_by_pnetid(char *pnet_name)
+{
+ struct smc_pnetentry *pnetelem, *tmp_pe;
+ int rc = -ENOENT;
+
+ write_lock(&smc_pnettable.lock);
+ list_for_each_entry_safe(pnetelem, tmp_pe, &smc_pnettable.pnetlist,
+ list) {
+ if (!strncmp(pnetelem->pnet_name, pnet_name,
+ sizeof(pnetelem->pnet_name))) {
+ list_del(&pnetelem->list);
+ dev_put(pnetelem->ndev);
+ kfree(pnetelem);
+ rc = 0;
+ break;
+ }
+ }
+ write_unlock(&smc_pnettable.lock);
+ return rc;
+}
+
+/* Remove a pnet entry mentioning a given network device from the pnet table.
+ */
+static int smc_pnet_remove_by_ndev(struct net_device *ndev)
+{
+ struct smc_pnetentry *pnetelem, *tmp_pe;
+ int rc = -ENOENT;
+
+ write_lock(&smc_pnettable.lock);
+ list_for_each_entry_safe(pnetelem, tmp_pe, &smc_pnettable.pnetlist,
+ list) {
+ if (pnetelem->ndev == ndev) {
+ list_del(&pnetelem->list);
+ dev_put(pnetelem->ndev);
+ kfree(pnetelem);
+ rc = 0;
+ break;
+ }
+ }
+ write_unlock(&smc_pnettable.lock);
+ return rc;
+}
+
+/* Remove a pnet entry mentioning a given ib device from the pnet table.
+ */
+int smc_pnet_remove_by_ibdev(struct smc_ib_device *ibdev)
+{
+ struct smc_pnetentry *pnetelem, *tmp_pe;
+ int rc = -ENOENT;
+
+ write_lock(&smc_pnettable.lock);
+ list_for_each_entry_safe(pnetelem, tmp_pe, &smc_pnettable.pnetlist,
+ list) {
+ if (pnetelem->smcibdev == ibdev) {
+ list_del(&pnetelem->list);
+ dev_put(pnetelem->ndev);
+ kfree(pnetelem);
+ rc = 0;
+ break;
+ }
+ }
+ write_unlock(&smc_pnettable.lock);
+ return rc;
+}
+
+/* Append a pnetid to the end of the pnet table if not already on this list.
+ */
+static int smc_pnet_enter(struct smc_pnetentry *new_pnetelem)
+{
+ struct smc_pnetentry *pnetelem;
+ int rc = -EEXIST;
+
+ write_lock(&smc_pnettable.lock);
+ list_for_each_entry(pnetelem, &smc_pnettable.pnetlist, list) {
+ if (!strncmp(pnetelem->pnet_name, new_pnetelem->pnet_name,
+ sizeof(new_pnetelem->pnet_name)) ||
+ !strncmp(pnetelem->ndev->name, new_pnetelem->ndev->name,
+ sizeof(new_pnetelem->ndev->name)) ||
+ smc_pnet_same_ibname(pnetelem,
+ new_pnetelem->smcibdev->ibdev->name,
+ new_pnetelem->ib_port))
+ goto found;
+ }
+ list_add_tail(&new_pnetelem->list, &smc_pnettable.pnetlist);
+ rc = 0;
+found:
+ write_unlock(&smc_pnettable.lock);
+ return rc;
+}
+
+/* The limit for pnetid is 16 characters.
+ * Valid characters should be (single-byte character set) a-z, A-Z, 0-9.
+ * Lower case letters are converted to upper case.
+ * Interior blanks should not be used.
+ */
+static bool smc_pnetid_valid(const char *pnet_name, char *pnetid)
+{
+ char *bf = skip_spaces(pnet_name);
+ size_t len = strlen(bf);
+ char *end = bf + len;
+
+ if (!len)
+ return false;
+ while (--end >= bf && isspace(*end))
+ ;
+ if (end - bf >= SMC_MAX_PNET_ID_LEN)
+ return false;
+ while (bf <= end) {
+ if (!isalnum(*bf))
+ return false;
+ *pnetid++ = islower(*bf) ? toupper(*bf) : *bf;
+ bf++;
+ }
+ *pnetid = '\0';
+ return true;
+}
+
+/* Find an infiniband device by a given name. The device might not exist. */
+struct smc_ib_device *smc_pnet_find_ib(char *ib_name)
+{
+ struct smc_ib_device *ibdev;
+
+ spin_lock(&smc_ib_devices.lock);
+ list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
+ if (!strncmp(ibdev->ibdev->name, ib_name,
+ sizeof(ibdev->ibdev->name))) {
+ goto out;
+ }
+ }
+ ibdev = NULL;
+out:
+ spin_unlock(&smc_ib_devices.lock);
+ return ibdev;
+}
+
+/* Parse the supplied netlink attributes and fill a pnetentry structure.
+ * For ethernet and infiniband device names verify that the devices exist.
+ */
+static int smc_pnet_fill_entry(struct net *net, struct smc_pnetentry *pnetelem,
+ struct nlattr *tb[])
+{
+ char *string, *ibname = NULL;
+ int rc = 0;
+
+ memset(pnetelem, 0, sizeof(*pnetelem));
+ INIT_LIST_HEAD(&pnetelem->list);
+ if (tb[SMC_PNETID_NAME]) {
+ string = (char *)nla_data(tb[SMC_PNETID_NAME]);
+ if (!smc_pnetid_valid(string, pnetelem->pnet_name)) {
+ rc = -EINVAL;
+ goto error;
+ }
+ }
+ if (tb[SMC_PNETID_ETHNAME]) {
+ string = (char *)nla_data(tb[SMC_PNETID_ETHNAME]);
+ pnetelem->ndev = dev_get_by_name(net, string);
+ if (!pnetelem->ndev)
+ return -ENOENT;
+ }
+ if (tb[SMC_PNETID_IBNAME]) {
+ ibname = (char *)nla_data(tb[SMC_PNETID_IBNAME]);
+ ibname = strim(ibname);
+ pnetelem->smcibdev = smc_pnet_find_ib(ibname);
+ if (!pnetelem->smcibdev) {
+ rc = -ENOENT;
+ goto error;
+ }
+ }
+ if (tb[SMC_PNETID_IBPORT]) {
+ pnetelem->ib_port = nla_get_u8(tb[SMC_PNETID_IBPORT]);
+ if (pnetelem->ib_port > SMC_MAX_PORTS) {
+ rc = -EINVAL;
+ goto error;
+ }
+ }
+ return 0;
+
+error:
+ if (pnetelem->ndev)
+ dev_put(pnetelem->ndev);
+ return rc;
+}
+
+/* Convert an smc_pnetentry to a netlink attribute sequence */
+static int smc_pnet_set_nla(struct sk_buff *msg, struct smc_pnetentry *pnetelem)
+{
+ if (nla_put_string(msg, SMC_PNETID_NAME, pnetelem->pnet_name) ||
+ nla_put_string(msg, SMC_PNETID_ETHNAME, pnetelem->ndev->name) ||
+ nla_put_string(msg, SMC_PNETID_IBNAME,
+ pnetelem->smcibdev->ibdev->name) ||
+ nla_put_u8(msg, SMC_PNETID_IBPORT, pnetelem->ib_port))
+ return -1;
+ return 0;
+}
+
+/* Retrieve one PNETID entry */
+static int smc_pnet_get(struct sk_buff *skb, struct genl_info *info)
+{
+ struct smc_pnetentry *pnetelem;
+ struct sk_buff *msg;
+ void *hdr;
+ int rc;
+
+ pnetelem = smc_pnet_find_pnetid(
+ (char *)nla_data(info->attrs[SMC_PNETID_NAME]));
+ if (!pnetelem)
+ return -ENOENT;
+ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
+ &smc_pnet_nl_family, 0, SMC_PNETID_GET);
+ if (!hdr) {
+ rc = -EMSGSIZE;
+ goto err_out;
+ }
+
+ if (smc_pnet_set_nla(msg, pnetelem)) {
+ rc = -ENOBUFS;
+ goto err_out;
+ }
+
+ genlmsg_end(msg, hdr);
+ return genlmsg_reply(msg, info);
+
+err_out:
+ nlmsg_free(msg);
+ return rc;
+}
+
+static int smc_pnet_add(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct smc_pnetentry *pnetelem;
+ int rc;
+
+ pnetelem = kzalloc(sizeof(*pnetelem), GFP_KERNEL);
+ if (!pnetelem)
+ return -ENOMEM;
+ rc = smc_pnet_fill_entry(net, pnetelem, info->attrs);
+ if (!rc)
+ rc = smc_pnet_enter(pnetelem);
+ if (rc) {
+ kfree(pnetelem);
+ return rc;
+ }
+ rc = smc_ib_remember_port_attr(pnetelem->smcibdev, pnetelem->ib_port);
+ if (rc)
+ smc_pnet_remove_by_pnetid(pnetelem->pnet_name);
+ return rc;
+}
+
+static int smc_pnet_del(struct sk_buff *skb, struct genl_info *info)
+{
+ return smc_pnet_remove_by_pnetid(
+ (char *)nla_data(info->attrs[SMC_PNETID_NAME]));
+}
+
+static int smc_pnet_dump_start(struct netlink_callback *cb)
+{
+ cb->args[0] = 0;
+ return 0;
+}
+
+static int smc_pnet_dumpinfo(struct sk_buff *skb,
+ u32 portid, u32 seq, u32 flags,
+ struct smc_pnetentry *pnetelem)
+{
+ void *hdr;
+
+ hdr = genlmsg_put(skb, portid, seq, &smc_pnet_nl_family,
+ flags, SMC_PNETID_GET);
+ if (!hdr)
+ return -ENOMEM;
+ if (smc_pnet_set_nla(skb, pnetelem) < 0) {
+ genlmsg_cancel(skb, hdr);
+ return -EMSGSIZE;
+ }
+ genlmsg_end(skb, hdr);
+ return 0;
+}
+
+static int smc_pnet_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct smc_pnetentry *pnetelem;
+ int idx = 0;
+
+ read_lock(&smc_pnettable.lock);
+ list_for_each_entry(pnetelem, &smc_pnettable.pnetlist, list) {
+ if (idx++ < cb->args[0])
+ continue;
+ if (smc_pnet_dumpinfo(skb, NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, NLM_F_MULTI,
+ pnetelem)) {
+ --idx;
+ break;
+ }
+ }
+ cb->args[0] = idx;
+ read_unlock(&smc_pnettable.lock);
+ return skb->len;
+}
+
+/* Remove and delete all pnetids from pnet table.
+ */
+static int smc_pnet_flush(struct sk_buff *skb, struct genl_info *info)
+{
+ struct smc_pnetentry *pnetelem, *tmp_pe;
+
+ write_lock(&smc_pnettable.lock);
+ list_for_each_entry_safe(pnetelem, tmp_pe, &smc_pnettable.pnetlist,
+ list) {
+ list_del(&pnetelem->list);
+ dev_put(pnetelem->ndev);
+ kfree(pnetelem);
+ }
+ write_unlock(&smc_pnettable.lock);
+ return 0;
+}
+
+/* SMC_PNETID generic netlink operation definition */
+static const struct genl_ops smc_pnet_ops[] = {
+ {
+ .cmd = SMC_PNETID_GET,
+ .flags = GENL_ADMIN_PERM,
+ .policy = smc_pnet_policy,
+ .doit = smc_pnet_get,
+ .dumpit = smc_pnet_dump,
+ .start = smc_pnet_dump_start
+ },
+ {
+ .cmd = SMC_PNETID_ADD,
+ .flags = GENL_ADMIN_PERM,
+ .policy = smc_pnet_policy,
+ .doit = smc_pnet_add
+ },
+ {
+ .cmd = SMC_PNETID_DEL,
+ .flags = GENL_ADMIN_PERM,
+ .policy = smc_pnet_policy,
+ .doit = smc_pnet_del
+ },
+ {
+ .cmd = SMC_PNETID_FLUSH,
+ .flags = GENL_ADMIN_PERM,
+ .policy = smc_pnet_policy,
+ .doit = smc_pnet_flush
+ }
+};
+
+/* SMC_PNETID family definition */
+static struct genl_family smc_pnet_nl_family = {
+ .hdrsize = 0,
+ .name = SMCR_GENL_FAMILY_NAME,
+ .version = SMCR_GENL_FAMILY_VERSION,
+ .maxattr = SMC_PNETID_MAX,
+ .netnsok = true,
+ .module = THIS_MODULE,
+ .ops = smc_pnet_ops,
+ .n_ops = ARRAY_SIZE(smc_pnet_ops)
+};
+
+static int smc_pnet_netdev_event(struct notifier_block *this,
+ unsigned long event, void *ptr)
+{
+ struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
+
+ switch (event) {
+ case NETDEV_REBOOT:
+ case NETDEV_UNREGISTER:
+ smc_pnet_remove_by_ndev(event_dev);
+ default:
+ break;
+ }
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block smc_netdev_notifier = {
+ .notifier_call = smc_pnet_netdev_event
+};
+
+int __init smc_pnet_init(void)
+{
+ int rc;
+
+ rc = genl_register_family(&smc_pnet_nl_family);
+ if (rc)
+ return rc;
+ rc = register_netdevice_notifier(&smc_netdev_notifier);
+ if (rc)
+ genl_unregister_family(&smc_pnet_nl_family);
+ return rc;
+}
+
+void smc_pnet_exit(void)
+{
+ smc_pnet_flush(NULL, NULL);
+ unregister_netdevice_notifier(&smc_netdev_notifier);
+ genl_unregister_family(&smc_pnet_nl_family);
+}
+
+/* PNET table analysis for a given sock:
+ * determine ib_device and port belonging to used internal TCP socket
+ * ethernet interface.
+ */
+void smc_pnet_find_roce_resource(struct sock *sk,
+ struct smc_ib_device **smcibdev, u8 *ibport)
+{
+ struct dst_entry *dst = sk_dst_get(sk);
+ struct smc_pnetentry *pnetelem;
+
+ *smcibdev = NULL;
+ *ibport = 0;
+
+ if (!dst)
+ return;
+ if (!dst->dev)
+ goto out_rel;
+ read_lock(&smc_pnettable.lock);
+ list_for_each_entry(pnetelem, &smc_pnettable.pnetlist, list) {
+ if (dst->dev == pnetelem->ndev) {
+ *smcibdev = pnetelem->smcibdev;
+ *ibport = pnetelem->ib_port;
+ break;
+ }
+ }
+ read_unlock(&smc_pnettable.lock);
+out_rel:
+ dst_release(dst);
+}