ibv_query_device_ex (3)

NAME

ibv_query_device_ex - query an RDMA device's attributes

SYNOPSIS

#include <infiniband/verbs.h>

int ibv_query_device_ex(struct ibv_context *context,
                        struct ibv_device_attr_ex *attr);

DESCRIPTION

ibv_query_device_ex() returns the attributes of the device with context context. The argument attr is a pointer to an ibv_device_attr_ex struct, as defined in <infiniband/verbs.h>.

struct ibv_device_attr_ex {
struct ibv_device_attr orig_attr;
uint32_t               comp_mask;                  /* Compatibility mask that defines which of the following variables are valid */
struct ibv_odp_caps    odp_caps;                   /* On-Demand Paging capabilities */
uint64_t               completion_timestamp_mask;  /* Completion timestamp mask (0 = unsupported) */
uint64_t               hca_core_clock;             /* The frequency (in kHZ) of the HCA (0 = unsupported) */
uint64_t               device_cap_flags_ex;    /* Extended device capability flags */
};

struct ibv_exp_odp_caps {
        uint64_t        general_odp_caps;  /* Mask with enum ibv_odp_general_cap_bits */
        struct {
                uint32_t        rc_odp_caps;      /* Mask with enum ibv_odp_tranport_cap_bits to know which operations are supported. */
                uint32_t        uc_odp_caps;      /* Mask with enum ibv_odp_tranport_cap_bits to know which operations are supported. */
                uint32_t        ud_odp_caps;      /* Mask with enum ibv_odp_tranport_cap_bits to know which operations are supported. */
        } per_transport_caps;
};

enum ibv_odp_general_cap_bits {
        IBV_ODP_SUPPORT = 1 << 0, /* On demand paging is supported */
};

enum ibv_odp_transport_cap_bits {
        IBV_ODP_SUPPORT_SEND     = 1 << 0, /* Send operations support on-demand paging */
        IBV_ODP_SUPPORT_RECV     = 1 << 1, /* Receive operations support on-demand paging */
        IBV_ODP_SUPPORT_WRITE    = 1 << 2, /* RDMA-Write operations support on-demand paging */
        IBV_ODP_SUPPORT_READ     = 1 << 3, /* RDMA-Read operations support on-demand paging */
        IBV_ODP_SUPPORT_ATOMIC   = 1 << 4, /* RDMA-Atomic operations support on-demand paging */
};

RETURN VALUE

ibv_query_device_ex() returns 0 on success, or the value of errno on failure (which indicates the failure reason).

NOTES

The maximum values returned by this function are the upper limits of supported resources by the device. However, it may not be possible to use these maximum values, since the actual number of any resource that can be created may be limited by the machine configuration, the amount of host memory, user permissions, and the amount of resources already in use by other users/processes.

SEE ALSO

ibv_query_device(3), ibv_open_device(3), ibv_query_port(3), ibv_query_pkey(3), ibv_query_gid(3)

AUTHORS

Majd Dibbiny <majd@mellanox.com>