diff options
Diffstat (limited to 'net/smc/smc_ib.c')
| -rw-r--r-- | net/smc/smc_ib.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c new file mode 100644 index 000000000000..7222b7ede900 --- /dev/null +++ b/net/smc/smc_ib.c @@ -0,0 +1,143 @@ +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * IB infrastructure: + * Establish SMC-R as an Infiniband Client to be notified about added and + * removed IB devices of type RDMA. + * Determine device and port characteristics for these IB devices. + * + * Copyright IBM Corp. 2016 + * + * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com> + */ + +#include <linux/random.h> +#include <rdma/ib_verbs.h> + +#include "smc_ib.h" +#include "smc.h" + +struct smc_ib_devices smc_ib_devices = { /* smc-registered ib devices */ + .lock = __SPIN_LOCK_UNLOCKED(smc_ib_devices.lock), + .list = LIST_HEAD_INIT(smc_ib_devices.list), +}; + +#define SMC_LOCAL_SYSTEMID_RESET "%%%%%%%" + +u8 local_systemid[SMC_SYSTEMID_LEN] = SMC_LOCAL_SYSTEMID_RESET; /* unique system + * identifier + */ + +static int smc_ib_fill_gid_and_mac(struct smc_ib_device *smcibdev, u8 ibport) +{ + struct net_device *ndev; + int rc; + + rc = ib_query_gid(smcibdev->ibdev, ibport, 0, + &smcibdev->gid[ibport - 1], NULL); + /* the SMC protocol requires specification of the roce MAC address; + * if net_device cannot be determined, it can be derived from gid 0 + */ + ndev = smcibdev->ibdev->get_netdev(smcibdev->ibdev, ibport); + if (ndev) { + memcpy(&smcibdev->mac, ndev->dev_addr, ETH_ALEN); + } else if (!rc) { + memcpy(&smcibdev->mac[ibport - 1][0], + &smcibdev->gid[ibport - 1].raw[8], 3); + memcpy(&smcibdev->mac[ibport - 1][3], + &smcibdev->gid[ibport - 1].raw[13], 3); + smcibdev->mac[ibport - 1][0] &= ~0x02; + } + return rc; +} + +/* Create an identifier unique for this instance of SMC-R. + * The MAC-address of the first active registered IB device + * plus a random 2-byte number is used to create this identifier. + * This name is delivered to the peer during connection initialization. + */ +static inline void smc_ib_define_local_systemid(struct smc_ib_device *smcibdev, + u8 ibport) +{ + memcpy(&local_systemid[2], &smcibdev->mac[ibport - 1], + sizeof(smcibdev->mac[ibport - 1])); + get_random_bytes(&local_systemid[0], 2); +} + +bool smc_ib_port_active(struct smc_ib_device *smcibdev, u8 ibport) +{ + return smcibdev->pattr[ibport - 1].state == IB_PORT_ACTIVE; +} + +int smc_ib_remember_port_attr(struct smc_ib_device *smcibdev, u8 ibport) +{ + int rc; + + memset(&smcibdev->pattr[ibport - 1], 0, + sizeof(smcibdev->pattr[ibport - 1])); + rc = ib_query_port(smcibdev->ibdev, ibport, + &smcibdev->pattr[ibport - 1]); + if (rc) + goto out; + rc = smc_ib_fill_gid_and_mac(smcibdev, ibport); + if (rc) + goto out; + if (!strncmp(local_systemid, SMC_LOCAL_SYSTEMID_RESET, + sizeof(local_systemid)) && + smc_ib_port_active(smcibdev, ibport)) + /* create unique system identifier */ + smc_ib_define_local_systemid(smcibdev, ibport); +out: + return rc; +} + +static struct ib_client smc_ib_client; + +/* callback function for ib_register_client() */ +static void smc_ib_add_dev(struct ib_device *ibdev) +{ + struct smc_ib_device *smcibdev; + + if (ibdev->node_type != RDMA_NODE_IB_CA) + return; + + smcibdev = kzalloc(sizeof(*smcibdev), GFP_KERNEL); + if (!smcibdev) + return; + + smcibdev->ibdev = ibdev; + + spin_lock(&smc_ib_devices.lock); + list_add_tail(&smcibdev->list, &smc_ib_devices.list); + spin_unlock(&smc_ib_devices.lock); + ib_set_client_data(ibdev, &smc_ib_client, smcibdev); +} + +/* callback function for ib_register_client() */ +static void smc_ib_remove_dev(struct ib_device *ibdev, void *client_data) +{ + struct smc_ib_device *smcibdev; + + smcibdev = ib_get_client_data(ibdev, &smc_ib_client); + ib_set_client_data(ibdev, &smc_ib_client, NULL); + spin_lock(&smc_ib_devices.lock); + list_del_init(&smcibdev->list); /* remove from smc_ib_devices */ + spin_unlock(&smc_ib_devices.lock); + kfree(smcibdev); +} + +static struct ib_client smc_ib_client = { + .name = "smc_ib", + .add = smc_ib_add_dev, + .remove = smc_ib_remove_dev, +}; + +int __init smc_ib_register_client(void) +{ + return ib_register_client(&smc_ib_client); +} + +void smc_ib_unregister_client(void) +{ + ib_unregister_client(&smc_ib_client); +} |