ibv_create_qp_ex, ibv_destroy_qp — create or destroy a queue pair (QP)
Synopsis
#include <infiniband/verbs.h>
struct ibv_qp *ibv_create_qp_ex(struct ibv_context *context,
struct ibv_qp_init_attr_ex *qp_init_attr);
int ibv_destroy_qp(struct ibv_qp *qp);Description
ibv_create_qp_ex() creates a queue pair (QP) associated with the protection domain pd. The argument qp_init_attr_ex is an ibv_qp_init_attr_ex struct, as defined in <infiniband/verbs.h>.
struct ibv_qp_init_attr_ex {
void *qp_context; /* Associated context of the QP */
struct ibv_cq *send_cq; /* CQ to be associated with the Send Queue (SQ) */
struct ibv_cq *recv_cq; /* CQ to be associated with the Receive Queue (RQ) */
struct ibv_srq *srq; /* SRQ handle if QP is to be associated with an SRQ, otherwise NULL */
struct ibv_qp_cap cap; /* QP capabilities */
enum ibv_qp_type qp_type; /* QP Transport Service Type: IBV_QPT_RC, IBV_QPT_UC, IBV_QPT_UD, IBV_QPT_RAW_PACKET or IBV_QPT_DRIVER */
int sq_sig_all; /* If set, each Work Request (WR) submitted to the SQ generates a completion entry */
uint32_t comp_mask; /* Identifies valid fields */
struct ibv_pd *pd; /* PD to be associated with the QP */
struct ibv_xrcd *xrcd; /* XRC domain to be associated with the target QP */
enum ibv_qp_create_flags create_flags; /* Creation flags for this QP */
uint16_t max_tso_header; /* Maximum TSO header size */
struct ibv_rwq_ind_table *rwq_ind_tbl; /* Indirection table to be associated with the QP */
struct ibv_rx_hash_conf rx_hash_conf; /* RX hash configuration to be used */
uint32_t source_qpn; /* Source QP number, creation flag IBV_QP_CREATE_SOURCE_QPN should be set, few NOTEs below */
uint64_t send_ops_flags; /* Select which QP send ops will be defined in struct ibv_qp_ex. Use enum ibv_qp_create_send_ops_flags */
};
struct ibv_qp_cap {
uint32_t max_send_wr; /* Requested max number of outstanding WRs in the SQ */
uint32_t max_recv_wr; /* Requested max number of outstanding WRs in the RQ */
uint32_t max_send_sge; /* Requested max number of scatter/gather (s/g) elements in a WR in the SQ */
uint32_t max_recv_sge; /* Requested max number of s/g elements in a WR in the SQ */
uint32_t max_inline_data;/* Requested max number of data (bytes) that can be posted inline to the SQ, otherwise 0 */
};
enum ibv_qp_create_flags {
IBV_QP_CREATE_BLOCK_SELF_MCAST_LB = 1 << 1, /* Prevent self multicast loopback */
IBV_QP_CREATE_SCATTER_FCS = 1 << 8, /* FCS field will be scattered to host memory */
IBV_QP_CREATE_CVLAN_STRIPPING = 1 << 9, /* CVLAN field will be stripped from incoming packets */
IBV_QP_CREATE_SOURCE_QPN = 1 << 10, /* The created QP will use the source_qpn as its wire QP number */
IBV_QP_CREATE_PCI_WRITE_END_PADDING = 1 << 11, /* Incoming packets will be padded to cacheline size */
};
struct ibv_rx_hash_conf {
uint8_t rx_hash_function; /* RX hash function, use enum ibv_rx_hash_function_flags */
uint8_t rx_hash_key_len; /* RX hash key length */
uint8_t *rx_hash_key; /* RX hash key data */
uint64_t rx_hash_fields_mask; /* RX fields that should participate in the hashing, use enum ibv_rx_hash_fields */
};
enum ibv_rx_hash_fields {
IBV_RX_HASH_SRC_IPV4 = 1 << 0,
IBV_RX_HASH_DST_IPV4 = 1 << 1,
IBV_RX_HASH_SRC_IPV6 = 1 << 2,
IBV_RX_HASH_DST_IPV6 = 1 << 3,
IBV_RX_HASH_SRC_PORT_TCP = 1 << 4,
IBV_RX_HASH_DST_PORT_TCP = 1 << 5,
IBV_RX_HASH_SRC_PORT_UDP = 1 << 6,
IBV_RX_HASH_DST_PORT_UDP = 1 << 7,
IBV_RX_HASH_IPSEC_SPI = 1 << 8,
/* When using tunneling protocol, e.g. VXLAN, then we have an inner (encapsulated packet) and outer.
* For applying RSS on the inner packet, then the following field should be set with one of the L3/L4 fields.
*/
IBV_RX_HASH_INNER = (1UL << 31),
};
struct ibv_qp_create_send_ops_flags {
IBV_QP_EX_WITH_RDMA_WRITE = 1 << 0,
IBV_QP_EX_WITH_RDMA_WRITE_WITH_IMM = 1 << 1,
IBV_QP_EX_WITH_SEND = 1 << 2,
IBV_QP_EX_WITH_SEND_WITH_IMM = 1 << 3,
IBV_QP_EX_WITH_RDMA_READ = 1 << 4,
IBV_QP_EX_WITH_ATOMIC_CMP_AND_SWP = 1 << 5,
IBV_QP_EX_WITH_ATOMIC_FETCH_AND_ADD = 1 << 6,
IBV_QP_EX_WITH_LOCAL_INV = 1 << 7,
IBV_QP_EX_WITH_BIND_MW = 1 << 8,
IBV_QP_EX_WITH_SEND_WITH_INV = 1 << 9,
IBV_QP_EX_WITH_TSO = 1 << 10,
};
The function ibv_create_qp_ex() will update the qp_init_attr_ex->cap struct with the actual QP values of the QP that was created; the values will be greater than or equal to the values requested.
ibv_destroy_qp() destroys the QP qp.
Return Value
ibv_create_qp_ex() returns a pointer to the created QP, or NULL if the request fails. Check the QP number (qp_num) in the returned QP.
ibv_destroy_qp() returns 0 on success, or the value of errno on failure (which indicates the failure reason).
Notes
The attributes max_recv_wr and max_recv_sge are ignored by ibv_create_qp_ex() if the QP is to be associated with an SRQ.
The attribute source_qpn is supported only on UD QP, without flow steering RX should not be possible.
Use ibv_qp_to_qp_ex() to get the ibv_qp_ex for accessing the send ops iterator interface, when QP create attr IBV_QP_INIT_ATTR_SEND_OPS_FLAGS is used.
ibv_destroy_qp() fails if the QP is attached to a multicast group.
IBV_QPT_DRIVER does not represent a specific service and is used for vendor specific QP logic.
See Also
ibv_alloc_pd(3), ibv_modify_qp(3), ibv_query_qp(3), ibv_create_rwq_ind_table(3)
Referenced By
ibv_create_rwq_ind_table(3), ibv_open_qp(3), ibv_open_xrcd(3), ibv_wr_post(3), mlx5dv_create_qp(3), mlx5dv_wr_post(3).