iflibtxrx(9) 맨 페이지 - 윈디하나의 솔라나라

개요

섹션
맨 페이지 이름
검색(S)

iflibtxrx(9)

IFLIBTXTX(9)             BSD Kernel Developer's Manual            IFLIBTXTX(9)

NAME
     iflibtxrx — Device Dependent Transmit and Receive Functions

SYNOPSIS
     #include <ifdi_if.h>

   Interface Manipulation Functions
     int
     isc_txd_encap(void *sc, if_pkt_into_t pi);

     void
     isc_txd_flush(void *sc, uint16_t qid, uint32_t _pidx_or_credits_);

     int *
     isc_txd_credits_update(void *sc, uint16_t qid, uint32_t credits);

     int *
     isc_rxd_available(void *sc, uint16_t qsid, uint32_t cidx);

     void *
     isc_rxd_refill(void *sc, uint16_t qsid, uint8_t flid, uint32_t pidx,
         uint64_t *paddrs, caddr_t *vaddrs, uint16_t count);

     void *
     isc_rxd_flush(void *sc, uint16_t qsid, uint8_t flid, uint32_t pidx);

     int
     isc_rxd_pkt_get(void *sc, if_rxd_info_t ri);

   Global Variables
     extern struct if_txrx

DATA STRUCTURES
     The device dependent mechanisms for handling packet transmit and receive
     are primarily defined by the functions named above.  The if_pkt_info data
     structure contains statistics and identifying info necessary for packet
     transmission.  While the data structure for packet receipt is the
     if_rxd_info structure.

   The if_pkt_info Structure
     The fields of struct if_pkt_info are as follows:

           ipi_len          (uint32_t) Denotes the size of packet to be sent
                            on the transmit queue.

           ipi_segs         (bus_dma_segment_t *) A pointer to the
                            bus_dma_segment of the device independent transfer
                            queue defined in iflib.

           ipi_qsidx        Unique index value assigned sequentially to each
                            transmit queue.  Used to reference the currently
                            transmitting queue.

           ipi_nsegs        (uint16_t) Number of descriptors to be read into
                            the device dependent transfer descriptors.

           ipi_ndescs       (uint16_t) Number of descriptors in use.  Calcu‐
                            lated by subtracting the old pidx value from the
                            new pidx value.

           ipi_flags        (uint16_t) Flags defined on a per packet basis.

           ipi_pidx         (uint32_t) Value of first pidx sent to the
                            isc_encap function for encapsulation and subse‐
                            quent transmission.

           ipi_new_pidx     (uint32_t) Value set after the termination of the
                            isc_encap function.  This value will become the
                            first pidx sent to the isc-encap the next time
                            that the function is called.

           The Following Fields Are Used For Offload Handling

           ipi_csum_flags   (uint64_t) Flags describing the checksum values,
                            used on a per packet basis.

           ipi_tso_segsz    (uint16_t) Size of the TSO Segment Size.

           ipi_mflags       (uint16_t) Flags describing the operational param‐
                            eters of the mbuf.

           ipi_vtag         (uint16_t) Contains the VLAN information in the
                            Ethernet Frame.

           ipi_etype        (uint16_t) Type of ethernet header protocol as
                            contained by the struct ether_vlan_header.

           ipi_ehrdlen      (uint8_t) Length of the Ethernet Header.

           ipi_ip_hlen      (uint8_t) Length of the TCP Header

           ipi_tcp_hlen     (uint8_t) Length of the TCP Header.

           ipi_tcp_hflags   (uint8_t) Flags describing the operational parame‐
                            ters of the TCP Header.

           ipi_ipproto      (uint8_t) Specifies the type of IP Protocol in
                            use.  Example TCP, UDP, or SCTP.

   The if_rxd_info Structure
     The fields of struct if_rxd_info are as follows:

           iri_qsidx        (uint16_t) Unique index value assigned sequen‐
                            tially to each receive queue.  Used to reference
                            the currently receiving queue.

           iri_vtag         (uint16_t) Contains the VLAN information in the
                            Ethernet Frame.

           iri_len          (uint16_t) Denotes the size of a received packet.

           iri_next_offset  (uint16_t) Denotes the offset value for the next
                            packet to be receive.  A Null value signifies the
                            end of packet.

           iri_cidx         (uint32_t) Denotes the index value of the packet
                            currently being processed in the consumer queue.

           iri_flowid       (uint32_t) Value of the RSS hash for the packet.

           iri_flags        (uint)
                             Flags describing the operational parameters of
                            the mbuf contained in the
                             receive packet.

           iri_csum_flags   (uint32_t) Flags describing the checksum value
                            contained in the receive packet.

           iri_csum_data    (uint32_t) Checksum data contained in the mbuf(9)
                            packet header.

           iri_m            (struct mbuf *) A mbuf for drivers that manage
                            their own receive queues.

           iri_ifp          (struct ifnet *) A link back to the interface
                            structure.  Utilized by drivers that have multiple
                            interface per softc.

           iri_rsstype      (uint8_t) The value of the RSS hash type.

           iri_pad          (uint8_t) The length of any padding contained by
                            the received data.

           iri_qidx         (uint8_t) Represents the type of queue event.  If
                            value >= 0 then it is the freelist id otherwise it
                            is a completion queue event.

FUNCTIONS
     All function calls are associated exclusively with either packet trans‐
     mission or receipt.  The void *sc passed as the first argument to all of
     the following functions represents the driver's softc.

   Transmit Packet Functions
           isc_txd_encap()
           Transmit function that sends a packet on an interface.  The
           if_pkt_info data structure contains data information fields
           describing the packet.  This function returns 0 if successful, oth‐
           erwise an error value is returned.

           isc_txd_flush()
           Flush function is called immediately after the isc_txd_encap func‐
           tion transmits a packet.  It updates the hardware producer index or
           increments the descriptors used to pidx_or_credits in the queue
           designated by the qid number.  This is often referred to as poking
           the doorbell register.

           isc_txd_credits_update()
           Credit function advances the buffer ring and calculates the credits
           (descriptors) processed.  Until the I/O is complete it cleans the
           range in case of multisegments and updates the count of processed
           packets.  The function returns the number of processed credits.

   Receive Packet Functions
           isc_rxd_available()
           Function calculates the remaining number of descriptors from a
           position given by idx.  The function returns this value.

           isc_rxd_refill()
           Starting with the physical address paddrs, the function reads a
           packet into the rx_ring until a value designated by count is
           reached.  vaddrs is typically not needed and is provided for
           devices that place their own metadata in the packet header.

           isc_rxd_flush()
           Flush function updates the producer pointer on the free list flid
           in queue set number qid to pidx to reflect the presence of new buf‐
           fers.

           isc_rxd_pkt_get()
           Process a single software descriptor.  rxr->rx_base[i] contains a
           descriptor that describes a received packet.  Hardware specific
           information about the buffer referred to by ri is returned in the
           data structure if_rxd_info

SEE ALSO
     iflibdd(9), iflibdi(9), mbuf(9)

AUTHORS
     This manual page was written by Nicole Graziano

BSD                             March 23, 2017                             BSD
맨 페이지 내용의 저작권은 맨 페이지 작성자에게 있습니다.
RSS ATOM XHTML 5 CSS3