/* * 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. */ static 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) { if (smc_ib_port_active(pnetelem->smcibdev, pnetelem->ib_port)) { *smcibdev = pnetelem->smcibdev; *ibport = pnetelem->ib_port; } break; } } read_unlock(&smc_pnettable.lock); out_rel: dst_release(dst); }