IBV_QUERY_DEVICE(3)					  Libibverbs Programmer's Manual				       IBV_QUERY_DEVICE(3)

NAME

       ibv_query_device - query an RDMA device's attributes

SYNOPSIS

       #include <infiniband/verbs.h>

       int ibv_query_device(struct ibv_context *context,
			    struct ibv_device_attr *device_attr);

DESCRIPTION

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

       struct ibv_device_attr {
	       char		       fw_ver[64];	       /* FW version */
	       uint64_t 	       node_guid;	       /* Node GUID (in network byte order) */
	       uint64_t 	       sys_image_guid;	       /* System image GUID (in network byte order) */
	       uint64_t 	       max_mr_size;	       /* Largest contiguous block that can be registered */
	       uint64_t 	       page_size_cap;	       /* Supported memory shift sizes */
	       uint32_t 	       vendor_id;	       /* Vendor ID, per IEEE */
	       uint32_t 	       vendor_part_id;	       /* Vendor supplied part ID */
	       uint32_t 	       hw_ver;		       /* Hardware version */
	       int		       max_qp;		       /* Maximum number of supported QPs */
	       int		       max_qp_wr;	       /* Maximum number of outstanding WR on any work queue */
	       int		       device_cap_flags;       /* HCA capabilities mask */
	       int		       max_sge; 	       /* Maximum number of s/g per WR for non-RD QPs */
	       int		       max_sge_rd;	       /* Maximum number of s/g per WR for RD QPs */
	       int		       max_cq;		       /* Maximum number of supported CQs */
	       int		       max_cqe; 	       /* Maximum number of CQE capacity per CQ */
	       int		       max_mr;		       /* Maximum number of supported MRs */
	       int		       max_pd;		       /* Maximum number of supported PDs */
	       int		       max_qp_rd_atom;	       /* Maximum number of RDMA Read & Atomic operations that can be outstanding per QP */
	       int		       max_ee_rd_atom;	       /* Maximum number of RDMA Read & Atomic operations that can be outstanding per EEC */
	       int		       max_res_rd_atom;        /* Maximum number of resources used for RDMA Read & Atomic operations by this HCA as the Target */
	       int		       max_qp_init_rd_atom;    /* Maximum depth per QP for initiation of RDMA Read & Atomic operations */
	       int		       max_ee_init_rd_atom;    /* Maximum depth per EEC for initiation of RDMA Read & Atomic operations */
	       enum ibv_atomic_cap     atomic_cap;	       /* Atomic operations support level */
	       int		       max_ee;		       /* Maximum number of supported EE contexts */
	       int		       max_rdd; 	       /* Maximum number of supported RD domains */
	       int		       max_mw;		       /* Maximum number of supported MWs */
	       int		       max_raw_ipv6_qp;        /* Maximum number of supported raw IPv6 datagram QPs */
	       int		       max_raw_ethy_qp;        /* Maximum number of supported Ethertype datagram QPs */
	       int		       max_mcast_grp;	       /* Maximum number of supported multicast groups */
	       int		       max_mcast_qp_attach;    /* Maximum number of QPs per multicast group which can be attached */
	       int		       max_total_mcast_qp_attach;/* Maximum number of QPs which can be attached to multicast groups */
	       int		       max_ah;		       /* Maximum number of supported address handles */
	       int		       max_fmr; 	       /* Maximum number of supported FMRs */
	       int		       max_map_per_fmr;        /* Maximum number of (re)maps per FMR before an unmap operation in required */
	       int		       max_srq; 	       /* Maximum number of supported SRQs */
	       int		       max_srq_wr;	       /* Maximum number of WRs per SRQ */
	       int		       max_srq_sge;	       /* Maximum number of s/g per SRQ */
	       uint16_t 	       max_pkeys;	       /* Maximum number of partitions */
	       uint8_t		       local_ca_ack_delay;     /* Local CA ack delay */
	       uint8_t		       phys_port_cnt;	       /* Number of physical ports */
       };

RETURN VALUE

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

AUTHORS

       Dotan Barak <dotanba@gmail.com>

libibverbs							    2006-10-31						       IBV_QUERY_DEVICE(3)