#ifndef _SDP_H_
#define _SDP_H_

#define LINUXKPI_PARAM_PREFIX ib_sdp_

#include "opt_ddb.h"
#include "opt_inet.h"
#include "opt_ofed.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/mbuf.h>
#include <sys/lock.h>
#include <sys/rwlock.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/protosw.h>
#include <sys/proc.h>
#include <sys/jail.h>
#include <sys/domain.h>

#ifdef DDB
#include <ddb/ddb.h>
#endif

#include <net/if.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/vnet.h>

#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/in_pcb.h>
#include <netinet/tcp.h>
#include <netinet/tcp_fsm.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>

#include <linux/device.h>
#include <linux/err.h>
#include <linux/sched.h>
#include <linux/workqueue.h>
#include <linux/wait.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/pci.h>

#include <rdma/ib_verbs.h>
#include <rdma/rdma_cm.h>
#include <rdma/ib_cm.h>
#include <rdma/ib_fmr_pool.h>
#include <rdma/rdma_sdp.h>

#ifdef SDP_DEBUG
#define CONFIG_INFINIBAND_SDP_DEBUG
#endif

#include "sdp_dbg.h"

#undef LIST_HEAD
/* From sys/queue.h */
#define LIST_HEAD(name, type)                                           \
struct name {                                                           \
        struct type *lh_first;  /* first element */                     \
}

/* Interval between successive polls in the Tx routine when polling is used
   instead of interrupts (in per-core Tx rings) - should be power of 2 */
#define SDP_TX_POLL_MODER       16
#define SDP_TX_POLL_TIMEOUT     (HZ / 20)
#define SDP_NAGLE_TIMEOUT (HZ / 10)

#define SDP_SRCAVAIL_CANCEL_TIMEOUT (HZ * 5)
#define SDP_SRCAVAIL_ADV_TIMEOUT (1 * HZ)
#define SDP_SRCAVAIL_PAYLOAD_LEN 1

#define SDP_RESOLVE_TIMEOUT 1000
#define SDP_ROUTE_TIMEOUT 1000
#define SDP_RETRY_COUNT 5
#define SDP_KEEPALIVE_TIME (120 * 60 * HZ)
#define SDP_FIN_WAIT_TIMEOUT (60 * HZ) /* like TCP_FIN_TIMEOUT */

#define SDP_TX_SIZE 0x40
#define SDP_RX_SIZE 0x40

#define SDP_FMR_SIZE (MIN(0x1000, PAGE_SIZE) / sizeof(u64))
#define SDP_FMR_POOL_SIZE       1024
#define SDP_FMR_DIRTY_SIZE      ( SDP_FMR_POOL_SIZE / 4 )

#define SDP_MAX_RDMA_READ_LEN (PAGE_SIZE * (SDP_FMR_SIZE - 2))

/* mb inlined data len - rest will be rx'ed into frags */
#define SDP_HEAD_SIZE (sizeof(struct sdp_bsdh))

/* limit tx payload len, if the sink supports bigger buffers than the source
 * can handle.
 * or rx fragment size (limited by sge->length size) */
#define SDP_MAX_PACKET  (1 << 16)
#define SDP_MAX_PAYLOAD (SDP_MAX_PACKET - SDP_HEAD_SIZE)

#define SDP_MAX_RECV_SGES (SDP_MAX_PACKET / MCLBYTES)
#define SDP_MAX_SEND_SGES (SDP_MAX_PACKET / MCLBYTES) + 2

#define SDP_NUM_WC 4

#define SDP_DEF_ZCOPY_THRESH 64*1024
#define SDP_MIN_ZCOPY_THRESH PAGE_SIZE
#define SDP_MAX_ZCOPY_THRESH 1048576

#define SDP_OP_RECV 0x800000000LL
#define SDP_OP_SEND 0x400000000LL
#define SDP_OP_RDMA 0x200000000LL
#define SDP_OP_NOP  0x100000000LL

/* how long (in jiffies) to block sender till tx completion*/
#define SDP_BZCOPY_POLL_TIMEOUT (HZ / 10)

#define SDP_AUTO_CONF   0xffff
#define AUTO_MOD_DELAY (HZ / 4)

struct sdp_mb_cb {
        __u32           seq;            /* Starting sequence number     */
        struct bzcopy_state      *bz;
        struct rx_srcavail_state *rx_sa;
        struct tx_srcavail_state *tx_sa;
};

#define M_PUSH  M_PROTO1        /* Do a 'push'. */
#define M_URG   M_PROTO2        /* Mark as urgent (oob). */

#define SDP_SKB_CB(__mb)      ((struct sdp_mb_cb *)&((__mb)->cb[0]))
#define BZCOPY_STATE(mb)      (SDP_SKB_CB(mb)->bz)
#define RX_SRCAVAIL_STATE(mb) (SDP_SKB_CB(mb)->rx_sa)
#define TX_SRCAVAIL_STATE(mb) (SDP_SKB_CB(mb)->tx_sa)

#ifndef MIN
#define MIN(a, b) (a < b ? a : b)
#endif

#define ring_head(ring)   (atomic_read(&(ring).head))
#define ring_tail(ring)   (atomic_read(&(ring).tail))
#define ring_posted(ring) (ring_head(ring) - ring_tail(ring))

#define rx_ring_posted(ssk) ring_posted(ssk->rx_ring)
#ifdef SDP_ZCOPY
#define tx_ring_posted(ssk) (ring_posted(ssk->tx_ring) + \
        (ssk->tx_ring.rdma_inflight ? ssk->tx_ring.rdma_inflight->busy : 0))
#else
#define tx_ring_posted(ssk) ring_posted(ssk->tx_ring)
#endif

extern int sdp_zcopy_thresh;
extern int rcvbuf_initial_size;
extern struct workqueue_struct *rx_comp_wq;
extern struct ib_client sdp_client;

enum sdp_mid {
        SDP_MID_HELLO = 0x0,
        SDP_MID_HELLO_ACK = 0x1,
        SDP_MID_DISCONN = 0x2,
        SDP_MID_ABORT = 0x3,
        SDP_MID_SENDSM = 0x4,
        SDP_MID_RDMARDCOMPL = 0x6,
        SDP_MID_SRCAVAIL_CANCEL = 0x8,
        SDP_MID_CHRCVBUF = 0xB,
        SDP_MID_CHRCVBUF_ACK = 0xC,
        SDP_MID_SINKAVAIL = 0xFD,
        SDP_MID_SRCAVAIL = 0xFE,
        SDP_MID_DATA = 0xFF,
};

enum sdp_flags {
        SDP_OOB_PRES = 1 << 0,
        SDP_OOB_PEND = 1 << 1,
};

enum {
        SDP_MIN_TX_CREDITS = 2
};

enum {
        SDP_ERR_ERROR   = -4,
        SDP_ERR_FAULT   = -3,
        SDP_NEW_SEG     = -2,
        SDP_DO_WAIT_MEM = -1
};

struct sdp_rrch {
        __u32 len;
} __attribute__((__packed__));

struct sdp_srcah {
        __u32 len;
        __u32 rkey;
        __u64 vaddr;
} __attribute__((__packed__));

struct sdp_buf {
        struct mbuf *mb;
        u64             mapping[SDP_MAX_SEND_SGES];
} __attribute__((__packed__));

struct sdp_chrecvbuf {
        u32 size;
} __attribute__((__packed__));

/* Context used for synchronous zero copy bcopy (BZCOPY) */
struct bzcopy_state {
        unsigned char __user  *u_base;
        int                    u_len;
        int                    left;
        int                    page_cnt;
        int                    cur_page;
        int                    cur_offset;
        int                    busy;
        struct sdp_sock      *ssk;
        struct page         **pages;
};

enum rx_sa_flag {
        RX_SA_ABORTED    = 2,
};

enum tx_sa_flag {
        TX_SA_SENDSM     = 0x01,
        TX_SA_CROSS_SEND = 0x02,
        TX_SA_INTRRUPTED = 0x04,
        TX_SA_TIMEDOUT   = 0x08,
        TX_SA_ERROR      = 0x10,
};

struct rx_srcavail_state {
        /* Advertised buffer stuff */
        u32 mseq;
        u32 used;
        u32 reported;
        u32 len;
        u32 rkey;
        u64 vaddr;

        /* Dest buff info */
        struct ib_umem *umem;
        struct ib_pool_fmr *fmr;

        /* Utility */
        u8  busy;
        enum rx_sa_flag  flags;
};

struct tx_srcavail_state {
        /* Data below 'busy' will be reset */
        u8              busy;

        struct ib_umem *umem;
        struct ib_pool_fmr *fmr;

        u32             bytes_sent;
        u32             bytes_acked;

        enum tx_sa_flag abort_flags;
        u8              posted;

        u32             mseq;
};

struct sdp_tx_ring {
#ifdef SDP_ZCOPY
        struct rx_srcavail_state *rdma_inflight;
#endif
        struct sdp_buf          *buffer;
        atomic_t                head;
        atomic_t                tail;
        struct ib_cq            *cq;

        atomic_t                credits;
#define tx_credits(ssk) (atomic_read(&ssk->tx_ring.credits))

        struct callout          timer;
        u16                     poll_cnt;
};

struct sdp_rx_ring {
        struct sdp_buf   *buffer;
        atomic_t          head;
        atomic_t          tail;
        struct ib_cq     *cq;

        int              destroyed;
        struct rwlock    destroyed_lock;
};

struct sdp_device {
        struct ib_pd            *pd;
        struct ib_fmr_pool      *fmr_pool;
};

struct sdp_moderation {
        unsigned long last_moder_packets;
        unsigned long last_moder_tx_packets;
        unsigned long last_moder_bytes;
        unsigned long last_moder_jiffies;
        int last_moder_time;
        u16 rx_usecs;
        u16 rx_frames;
        u16 tx_usecs;
        u32 pkt_rate_low;
        u16 rx_usecs_low;
        u32 pkt_rate_high;
        u16 rx_usecs_high;
        u16 sample_interval;
        u16 adaptive_rx_coal;
        u32 msg_enable;

        int moder_cnt;
        int moder_time;
};

/* These are flags fields. */
#define SDP_TIMEWAIT    0x0001          /* In ssk timewait state. */
#define SDP_DROPPED     0x0002          /* Socket has been dropped. */
#define SDP_SOCKREF     0x0004          /* Holding a sockref for close. */
#define SDP_NODELAY     0x0008          /* Disble nagle. */
#define SDP_NEEDFIN     0x0010          /* Send a fin on the next tx. */
#define SDP_DREQWAIT    0x0020          /* Waiting on DREQ. */
#define SDP_DESTROY     0x0040          /* Being destroyed. */
#define SDP_DISCON      0x0080          /* rdma_disconnect is owed. */

/* These are oobflags */
#define SDP_HADOOB      0x0001          /* Had OOB data. */
#define SDP_HAVEOOB     0x0002          /* Have OOB data. */

struct sdp_sock {
        LIST_ENTRY(sdp_sock) list;
        struct socket *socket;
        struct rdma_cm_id *id;
        struct ib_device *ib_device;
        struct sdp_device *sdp_dev;
        struct ib_qp *qp;
        struct ucred *cred;
        struct callout keep2msl;        /* 2msl and keepalive timer. */
        struct callout nagle_timer;     /* timeout waiting for ack */
        struct ib_ucontext context;
        in_port_t lport;
        in_addr_t laddr;
        in_port_t fport;
        in_addr_t faddr;
        int flags;
        int oobflags;           /* protected by rx lock. */
        int state;
        int softerror;
        int recv_bytes;         /* Bytes per recv. buf including header */
        int xmit_size_goal;
        char iobc;

        struct sdp_rx_ring rx_ring;
        struct sdp_tx_ring tx_ring;
        struct rwlock   lock;
        struct mbufq    rxctlq;         /* received control packets */

        int qp_active;  /* XXX Flag. */
        int max_sge;
        struct work_struct rx_comp_work;
#define rcv_nxt(ssk) atomic_read(&(ssk->rcv_nxt))
        atomic_t rcv_nxt;

        /* SDP specific */
        atomic_t mseq_ack;
#define mseq_ack(ssk) (atomic_read(&ssk->mseq_ack))
        unsigned max_bufs;      /* Initial buffers offered by other side */
        unsigned min_bufs;      /* Low water mark to wake senders */

        unsigned long nagle_last_unacked; /* mseq of lastest unacked packet */

        atomic_t               remote_credits;
#define remote_credits(ssk) (atomic_read(&ssk->remote_credits))
        int               poll_cq;

        /* SDP slow start */
        int recv_request_head;  /* mark the rx_head when the resize request
                                   was received */
        int recv_request;       /* XXX flag if request to resize was received */

        unsigned long tx_packets;
        unsigned long rx_packets;
        unsigned long tx_bytes;
        unsigned long rx_bytes;
        struct sdp_moderation auto_mod;
        struct task shutdown_task;
#ifdef SDP_ZCOPY
        struct tx_srcavail_state *tx_sa;
        struct rx_srcavail_state *rx_sa;
        spinlock_t tx_sa_lock;
        struct delayed_work srcavail_cancel_work;
        int srcavail_cancel_mseq;
        /* ZCOPY data: -1:use global; 0:disable zcopy; >0: zcopy threshold */
        int zcopy_thresh;
#endif
};

#define sdp_sk(so)      ((struct sdp_sock *)(so->so_pcb))

#define SDP_RLOCK(ssk)          rw_rlock(&(ssk)->lock)
#define SDP_WLOCK(ssk)          rw_wlock(&(ssk)->lock)
#define SDP_RUNLOCK(ssk)        rw_runlock(&(ssk)->lock)
#define SDP_WUNLOCK(ssk)        rw_wunlock(&(ssk)->lock)
#define SDP_WLOCK_ASSERT(ssk)   rw_assert(&(ssk)->lock, RA_WLOCKED)
#define SDP_RLOCK_ASSERT(ssk)   rw_assert(&(ssk)->lock, RA_RLOCKED)
#define SDP_LOCK_ASSERT(ssk)    rw_assert(&(ssk)->lock, RA_LOCKED)

MALLOC_DECLARE(M_SDP);
SYSCTL_DECL(_net_inet_sdp);

static inline void tx_sa_reset(struct tx_srcavail_state *tx_sa)
{
        memset((void *)&tx_sa->busy, 0,
                        sizeof(*tx_sa) - offsetof(typeof(*tx_sa), busy));
}

static inline void rx_ring_unlock(struct sdp_rx_ring *rx_ring)
{
        rw_runlock(&rx_ring->destroyed_lock);
}

static inline int rx_ring_trylock(struct sdp_rx_ring *rx_ring)
{
        rw_rlock(&rx_ring->destroyed_lock);
        if (rx_ring->destroyed) {
                rx_ring_unlock(rx_ring);
                return 0;
        }
        return 1;
}

static inline void rx_ring_destroy_lock(struct sdp_rx_ring *rx_ring)
{
        rw_wlock(&rx_ring->destroyed_lock);
        rx_ring->destroyed = 1;
        rw_wunlock(&rx_ring->destroyed_lock);
}

static inline void sdp_arm_rx_cq(struct sdp_sock *ssk)
{
        sdp_prf(ssk->socket, NULL, "Arming RX cq");
        sdp_dbg_data(ssk->socket, "Arming RX cq\n");

        ib_req_notify_cq(ssk->rx_ring.cq, IB_CQ_NEXT_COMP);
}

static inline void sdp_arm_tx_cq(struct sdp_sock *ssk)
{
        sdp_prf(ssk->socket, NULL, "Arming TX cq");
        sdp_dbg_data(ssk->socket, "Arming TX cq. credits: %d, posted: %d\n",
                tx_credits(ssk), tx_ring_posted(ssk));

        ib_req_notify_cq(ssk->tx_ring.cq, IB_CQ_NEXT_COMP);
}

/* return the min of:
 * - tx credits
 * - free slots in tx_ring (not including SDP_MIN_TX_CREDITS
 */
static inline int tx_slots_free(struct sdp_sock *ssk)
{
        int min_free;

        min_free = MIN(tx_credits(ssk),
                        SDP_TX_SIZE - tx_ring_posted(ssk));
        if (min_free < SDP_MIN_TX_CREDITS)
                return 0;

        return min_free - SDP_MIN_TX_CREDITS;
};

/* utilities */
static inline char *mid2str(int mid)
{
#define ENUM2STR(e) [e] = #e
        static char *mid2str[] = {
                ENUM2STR(SDP_MID_HELLO),
                ENUM2STR(SDP_MID_HELLO_ACK),
                ENUM2STR(SDP_MID_ABORT),
                ENUM2STR(SDP_MID_DISCONN),
                ENUM2STR(SDP_MID_SENDSM),
                ENUM2STR(SDP_MID_RDMARDCOMPL),
                ENUM2STR(SDP_MID_SRCAVAIL_CANCEL),
                ENUM2STR(SDP_MID_CHRCVBUF),
                ENUM2STR(SDP_MID_CHRCVBUF_ACK),
                ENUM2STR(SDP_MID_DATA),
                ENUM2STR(SDP_MID_SRCAVAIL),
                ENUM2STR(SDP_MID_SINKAVAIL),
        };

        if (mid >= ARRAY_SIZE(mid2str))
                return NULL;

        return mid2str[mid];
}

static inline struct mbuf *
sdp_alloc_mb(struct socket *sk, u8 mid, int size, int wait)
{
        struct sdp_bsdh *h;
        struct mbuf *mb;

        MGETHDR(mb, wait, MT_DATA);
        if (mb == NULL)
                return (NULL);
        mb->m_pkthdr.len = mb->m_len = sizeof(struct sdp_bsdh);
        h = mtod(mb, struct sdp_bsdh *);
        h->mid = mid;

        return mb;
}
static inline struct mbuf *
sdp_alloc_mb_data(struct socket *sk, int wait)
{
        return sdp_alloc_mb(sk, SDP_MID_DATA, 0, wait);
}

static inline struct mbuf *
sdp_alloc_mb_disconnect(struct socket *sk, int wait)
{
        return sdp_alloc_mb(sk, SDP_MID_DISCONN, 0, wait);
}

static inline void *
mb_put(struct mbuf *mb, int len)
{
        uint8_t *data;

        data = mb->m_data;
        data += mb->m_len;
        mb->m_len += len;
        return (void *)data;
}

static inline struct mbuf *
sdp_alloc_mb_chrcvbuf_ack(struct socket *sk, int size, int wait)
{
        struct mbuf *mb;
        struct sdp_chrecvbuf *resp_size;

        mb = sdp_alloc_mb(sk, SDP_MID_CHRCVBUF_ACK, sizeof(*resp_size), wait);
        if (mb == NULL)
                return (NULL);
        resp_size = (struct sdp_chrecvbuf *)mb_put(mb, sizeof *resp_size);
        resp_size->size = htonl(size);

        return mb;
}

static inline struct mbuf *
sdp_alloc_mb_srcavail(struct socket *sk, u32 len, u32 rkey, u64 vaddr, int wait)
{
        struct mbuf *mb;
        struct sdp_srcah *srcah;

        mb = sdp_alloc_mb(sk, SDP_MID_SRCAVAIL, sizeof(*srcah), wait);
        if (mb == NULL)
                return (NULL);
        srcah = (struct sdp_srcah *)mb_put(mb, sizeof(*srcah));
        srcah->len = htonl(len);
        srcah->rkey = htonl(rkey);
        srcah->vaddr = cpu_to_be64(vaddr);

        return mb;
}

static inline struct mbuf *
sdp_alloc_mb_srcavail_cancel(struct socket *sk, int wait)
{
        return sdp_alloc_mb(sk, SDP_MID_SRCAVAIL_CANCEL, 0, wait);
}

static inline struct mbuf *
sdp_alloc_mb_rdmardcompl(struct socket *sk, u32 len, int wait)
{
        struct mbuf *mb;
        struct sdp_rrch *rrch;

        mb = sdp_alloc_mb(sk, SDP_MID_RDMARDCOMPL, sizeof(*rrch), wait);
        if (mb == NULL)
                return (NULL);
        rrch = (struct sdp_rrch *)mb_put(mb, sizeof(*rrch));
        rrch->len = htonl(len);

        return mb;
}

static inline struct mbuf *
sdp_alloc_mb_sendsm(struct socket *sk, int wait)
{
        return sdp_alloc_mb(sk, SDP_MID_SENDSM, 0, wait);
}
static inline int sdp_tx_ring_slots_left(struct sdp_sock *ssk)
{
        return SDP_TX_SIZE - tx_ring_posted(ssk);
}

static inline int credit_update_needed(struct sdp_sock *ssk)
{
        int c;

        c = remote_credits(ssk);
        if (likely(c > SDP_MIN_TX_CREDITS))
                c += c/2;
        return unlikely(c < rx_ring_posted(ssk)) &&
            likely(tx_credits(ssk) > 0) &&
            likely(sdp_tx_ring_slots_left(ssk));
}


#define SDPSTATS_COUNTER_INC(stat)
#define SDPSTATS_COUNTER_ADD(stat, val)
#define SDPSTATS_COUNTER_MID_INC(stat, mid)
#define SDPSTATS_HIST_LINEAR(stat, size)
#define SDPSTATS_HIST(stat, size)

static inline void
sdp_cleanup_sdp_buf(struct sdp_sock *ssk, struct sdp_buf *sbuf,
    enum dma_data_direction dir)
{
        struct ib_device *dev;
        struct mbuf *mb;
        int i;

        dev = ssk->ib_device;
        for (i = 0, mb = sbuf->mb; mb != NULL; mb = mb->m_next, i++)
                ib_dma_unmap_single(dev, sbuf->mapping[i], mb->m_len, dir);
}

/* sdp_main.c */
void sdp_set_default_moderation(struct sdp_sock *ssk);
void sdp_start_keepalive_timer(struct socket *sk);
void sdp_urg(struct sdp_sock *ssk, struct mbuf *mb);
void sdp_cancel_dreq_wait_timeout(struct sdp_sock *ssk);
void sdp_abort(struct socket *sk);
struct sdp_sock *sdp_notify(struct sdp_sock *ssk, int error);


/* sdp_cma.c */
int sdp_cma_handler(struct rdma_cm_id *, struct rdma_cm_event *);

/* sdp_tx.c */
int sdp_tx_ring_create(struct sdp_sock *ssk, struct ib_device *device);
void sdp_tx_ring_destroy(struct sdp_sock *ssk);
int sdp_xmit_poll(struct sdp_sock *ssk, int force);
void sdp_post_send(struct sdp_sock *ssk, struct mbuf *mb);
void sdp_post_sends(struct sdp_sock *ssk, int wait);
void sdp_post_keepalive(struct sdp_sock *ssk);

/* sdp_rx.c */
void sdp_rx_ring_init(struct sdp_sock *ssk);
int sdp_rx_ring_create(struct sdp_sock *ssk, struct ib_device *device);
void sdp_rx_ring_destroy(struct sdp_sock *ssk);
int sdp_resize_buffers(struct sdp_sock *ssk, u32 new_size);
int sdp_init_buffers(struct sdp_sock *ssk, u32 new_size);
void sdp_do_posts(struct sdp_sock *ssk);
void sdp_rx_comp_full(struct sdp_sock *ssk);

/* sdp_zcopy.c */
struct kiocb;
int sdp_sendmsg_zcopy(struct kiocb *iocb, struct socket *sk, struct iovec *iov);
int sdp_handle_srcavail(struct sdp_sock *ssk, struct sdp_srcah *srcah);
void sdp_handle_sendsm(struct sdp_sock *ssk, u32 mseq_ack);
void sdp_handle_rdma_read_compl(struct sdp_sock *ssk, u32 mseq_ack,
                u32 bytes_completed);
int sdp_handle_rdma_read_cqe(struct sdp_sock *ssk);
int sdp_rdma_to_iovec(struct socket *sk, struct iovec *iov, struct mbuf *mb,
                unsigned long *used);
int sdp_post_rdma_rd_compl(struct sdp_sock *ssk,
                struct rx_srcavail_state *rx_sa);
int sdp_post_sendsm(struct socket *sk);
void srcavail_cancel_timeout(struct work_struct *work);
void sdp_abort_srcavail(struct socket *sk);
void sdp_abort_rdma_read(struct socket *sk);
int sdp_process_rx(struct sdp_sock *ssk);

#endif