rds.h

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/*
 * Copyright (c) 2008 Oracle.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */

#ifndef _LINUX_RDS_H
#define _LINUX_RDS_H

#include <linux/types.h>

#define RDS_IB_ABI_VERSION      0x301

/*
 * setsockopt/getsockopt for SOL_RDS
 */
#define RDS_CANCEL_SENT_TO          1
#define RDS_GET_MR          2
#define RDS_FREE_MR         3
/* deprecated: RDS_BARRIER 4 */
#define RDS_RECVERR         5
#define RDS_CONG_MONITOR        6
#define RDS_GET_MR_FOR_DEST     7

/*
 * Control message types for SOL_RDS.
 *
 * CMSG_RDMA_ARGS (sendmsg)
 *  Request a RDMA transfer to/from the specified
 *  memory ranges.
 *  The cmsg_data is a struct rds_rdma_args.
 * RDS_CMSG_RDMA_DEST (recvmsg, sendmsg)
 *  Kernel informs application about intended
 *  source/destination of a RDMA transfer
 * RDS_CMSG_RDMA_MAP (sendmsg)
 *  Application asks kernel to map the given
 *  memory range into a IB MR, and send the
 *  R_Key along in an RDS extension header.
 *  The cmsg_data is a struct rds_get_mr_args,
 *  the same as for the GET_MR setsockopt.
 * RDS_CMSG_RDMA_STATUS (recvmsg)
 *  Returns the status of a completed RDMA operation.
 */
#define RDS_CMSG_RDMA_ARGS      1
#define RDS_CMSG_RDMA_DEST      2
#define RDS_CMSG_RDMA_MAP       3
#define RDS_CMSG_RDMA_STATUS        4
#define RDS_CMSG_CONG_UPDATE        5
#define RDS_CMSG_ATOMIC_FADD        6
#define RDS_CMSG_ATOMIC_CSWP        7
#define RDS_CMSG_MASKED_ATOMIC_FADD 8
#define RDS_CMSG_MASKED_ATOMIC_CSWP 9

#define RDS_INFO_FIRST          10000
#define RDS_INFO_COUNTERS       10000
#define RDS_INFO_CONNECTIONS        10001
/* 10002 aka RDS_INFO_FLOWS is deprecated */
#define RDS_INFO_SEND_MESSAGES      10003
#define RDS_INFO_RETRANS_MESSAGES       10004
#define RDS_INFO_RECV_MESSAGES          10005
#define RDS_INFO_SOCKETS                10006
#define RDS_INFO_TCP_SOCKETS            10007
#define RDS_INFO_IB_CONNECTIONS     10008
#define RDS_INFO_CONNECTION_STATS   10009
#define RDS_INFO_IWARP_CONNECTIONS  10010
#define RDS_INFO_LAST           10010

struct rds_info_counter {
    uint8_t name[32];
    uint64_t    value;
} __attribute__((packed));

#define RDS_INFO_CONNECTION_FLAG_SENDING    0x01
#define RDS_INFO_CONNECTION_FLAG_CONNECTING 0x02
#define RDS_INFO_CONNECTION_FLAG_CONNECTED  0x04

#define TRANSNAMSIZ 16

struct rds_info_connection {
    uint64_t    next_tx_seq;
    uint64_t    next_rx_seq;
    __be32      laddr;
    __be32      faddr;
    uint8_t transport[TRANSNAMSIZ];     /* null term ascii */
    uint8_t flags;
} __attribute__((packed));

#define RDS_INFO_MESSAGE_FLAG_ACK               0x01
#define RDS_INFO_MESSAGE_FLAG_FAST_ACK          0x02

struct rds_info_message {
    uint64_t    seq;
    uint32_t    len;
    __be32      laddr;
    __be32      faddr;
    __be16      lport;
    __be16      fport;
    uint8_t flags;
} __attribute__((packed));

struct rds_info_socket {
    uint32_t    sndbuf;
    __be32      bound_addr;
    __be32      connected_addr;
    __be16      bound_port;
    __be16      connected_port;
    uint32_t    rcvbuf;
    uint64_t    inum;
} __attribute__((packed));

struct rds_info_tcp_socket {
    __be32          local_addr;
    __be16          local_port;
    __be32          peer_addr;
    __be16          peer_port;
    uint64_t       hdr_rem;
    uint64_t       data_rem;
    uint32_t       last_sent_nxt;
    uint32_t       last_expected_una;
    uint32_t       last_seen_una;
} __attribute__((packed));

#define RDS_IB_GID_LEN  16
struct rds_info_rdma_connection {
    __be32      src_addr;
    __be32      dst_addr;
    uint8_t     src_gid[RDS_IB_GID_LEN];
    uint8_t     dst_gid[RDS_IB_GID_LEN];

    uint32_t    max_send_wr;
    uint32_t    max_recv_wr;
    uint32_t    max_send_sge;
    uint32_t    rdma_mr_max;
    uint32_t    rdma_mr_size;
};

/*
 * Congestion monitoring.
 * Congestion control in RDS happens at the host connection
 * level by exchanging a bitmap marking congested ports.
 * By default, a process sleeping in poll() is always woken
 * up when the congestion map is updated.
 * With explicit monitoring, an application can have more
 * fine-grained control.
 * The application installs a 64bit mask value in the socket,
 * where each bit corresponds to a group of ports.
 * When a congestion update arrives, RDS checks the set of
 * ports that are now uncongested against the list bit mask
 * installed in the socket, and if they overlap, we queue a
 * cong_notification on the socket.
 *
 * To install the congestion monitor bitmask, use RDS_CONG_MONITOR
 * with the 64bit mask.
 * Congestion updates are received via RDS_CMSG_CONG_UPDATE
 * control messages.
 *
 * The correspondence between bits and ports is
 *  1 << (portnum % 64)
 */
#define RDS_CONG_MONITOR_SIZE   64
#define RDS_CONG_MONITOR_BIT(port)  (((unsigned int) port) % RDS_CONG_MONITOR_SIZE)
#define RDS_CONG_MONITOR_MASK(port) (1ULL << RDS_CONG_MONITOR_BIT(port))

/*
 * RDMA related types
 */

/*
 * This encapsulates a remote memory location.
 * In the current implementation, it contains the R_Key
 * of the remote memory region, and the offset into it
 * (so that the application does not have to worry about
 * alignment).
 */
typedef uint64_t    rds_rdma_cookie_t;

struct rds_iovec {
    uint64_t    addr;
    uint64_t    bytes;
};

struct rds_get_mr_args {
    struct rds_iovec vec;
    uint64_t    cookie_addr;
    uint64_t    flags;
};

struct rds_get_mr_for_dest_args {
    struct sockaddr_storage dest_addr;
    struct rds_iovec    vec;
    uint64_t        cookie_addr;
    uint64_t        flags;
};

struct rds_free_mr_args {
    rds_rdma_cookie_t cookie;
    uint64_t    flags;
};

struct rds_rdma_args {
    rds_rdma_cookie_t cookie;
    struct rds_iovec remote_vec;
    uint64_t    local_vec_addr;
    uint64_t    nr_local;
    uint64_t    flags;
    uint64_t    user_token;
};

struct rds_atomic_args {
    rds_rdma_cookie_t cookie;
    uint64_t    local_addr;
    uint64_t    remote_addr;
    union {
        struct {
            uint64_t    compare;
            uint64_t    swap;
        } cswp;
        struct {
            uint64_t    add;
        } fadd;
        struct {
            uint64_t    compare;
            uint64_t    swap;
            uint64_t    compare_mask;
            uint64_t    swap_mask;
        } m_cswp;
        struct {
            uint64_t    add;
            uint64_t    nocarry_mask;
        } m_fadd;
    };
    uint64_t    flags;
    uint64_t    user_token;
};

struct rds_rdma_notify {
    uint64_t    user_token;
    int32_t     status;
};

#define RDS_RDMA_SUCCESS    0
#define RDS_RDMA_REMOTE_ERROR   1
#define RDS_RDMA_CANCELED   2
#define RDS_RDMA_DROPPED    3
#define RDS_RDMA_OTHER_ERROR    4

/*
 * Common set of flags for all RDMA related structs
 */
#define RDS_RDMA_READWRITE  0x0001
#define RDS_RDMA_FENCE      0x0002  /* use FENCE for immediate send */
#define RDS_RDMA_INVALIDATE 0x0004  /* invalidate R_Key after freeing MR */
#define RDS_RDMA_USE_ONCE   0x0008  /* free MR after use */
#define RDS_RDMA_DONTWAIT   0x0010  /* Don't wait in SET_BARRIER */
#define RDS_RDMA_NOTIFY_ME  0x0020  /* Notify when operation completes */
#define RDS_RDMA_SILENT     0x0040  /* Do not interrupt remote */

#endif /* IB_RDS_H */