/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (c) 2016 Chelsio Communications, Inc.
 */

#ifndef __CXGBIT_H__
#define __CXGBIT_H__

#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/idr.h>
#include <linux/completion.h>
#include <linux/netdevice.h>
#include <linux/sched.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/inet.h>
#include <linux/wait.h>
#include <linux/kref.h>
#include <linux/timer.h>
#include <linux/io.h>

#include <asm/byteorder.h>

#include <net/net_namespace.h>

#include <target/iscsi/iscsi_transport.h>
#include <iscsi_target_parameters.h>
#include <iscsi_target_login.h>

#include "t4_regs.h"
#include "t4_msg.h"
#include "cxgb4.h"
#include "cxgb4_uld.h"
#include "l2t.h"
#include "libcxgb_ppm.h"
#include "cxgbit_lro.h"

extern struct mutex cdev_list_lock;
extern struct list_head cdev_list_head;
struct cxgbit_np;

struct cxgbit_sock;

struct cxgbit_cmd {
        struct scatterlist sg;
        struct cxgbi_task_tag_info ttinfo;
        bool setup_ddp;
        bool release;
};

#define CXGBIT_MAX_ISO_PAYLOAD  \
        min_t(u32, MAX_SKB_FRAGS * PAGE_SIZE, 65535)

struct cxgbit_iso_info {
        u8 flags;
        u32 mpdu;
        u32 len;
        u32 burst_len;
};

enum cxgbit_skcb_flags {
        SKCBF_TX_NEED_HDR       = (1 << 0), /* packet needs a header */
        SKCBF_TX_FLAG_COMPL     = (1 << 1), /* wr completion flag */
        SKCBF_TX_ISO            = (1 << 2), /* iso cpl in tx skb */
        SKCBF_RX_LRO            = (1 << 3), /* lro skb */
};

struct cxgbit_skb_rx_cb {
        u8 opcode;
        void *pdu_cb;
        void (*backlog_fn)(struct cxgbit_sock *, struct sk_buff *);
};

struct cxgbit_skb_tx_cb {
        u8 submode;
        u32 extra_len;
};

union cxgbit_skb_cb {
        struct {
                u8 flags;
                union {
                        struct cxgbit_skb_tx_cb tx;
                        struct cxgbit_skb_rx_cb rx;
                };
        };

        struct {
                /* This member must be first. */
                struct l2t_skb_cb l2t;
                struct sk_buff *wr_next;
        };
};

#define CXGBIT_SKB_CB(skb)      ((union cxgbit_skb_cb *)&((skb)->cb[0]))
#define cxgbit_skcb_flags(skb)          (CXGBIT_SKB_CB(skb)->flags)
#define cxgbit_skcb_submode(skb)        (CXGBIT_SKB_CB(skb)->tx.submode)
#define cxgbit_skcb_tx_wr_next(skb)     (CXGBIT_SKB_CB(skb)->wr_next)
#define cxgbit_skcb_tx_extralen(skb)    (CXGBIT_SKB_CB(skb)->tx.extra_len)
#define cxgbit_skcb_rx_opcode(skb)      (CXGBIT_SKB_CB(skb)->rx.opcode)
#define cxgbit_skcb_rx_backlog_fn(skb)  (CXGBIT_SKB_CB(skb)->rx.backlog_fn)
#define cxgbit_rx_pdu_cb(skb)           (CXGBIT_SKB_CB(skb)->rx.pdu_cb)

static inline void *cplhdr(struct sk_buff *skb)
{
        return skb->data;
}

enum cxgbit_cdev_flags {
        CDEV_STATE_UP = 0,
        CDEV_ISO_ENABLE,
        CDEV_DDP_ENABLE,
};

#define NP_INFO_HASH_SIZE 32

struct np_info {
        struct np_info *next;
        struct cxgbit_np *cnp;
        unsigned int stid;
};

struct cxgbit_list_head {
        struct list_head list;
        /* device lock */
        spinlock_t lock;
};

struct cxgbit_device {
        struct list_head list;
        struct cxgb4_lld_info lldi;
        struct np_info *np_hash_tab[NP_INFO_HASH_SIZE];
        /* np lock */
        spinlock_t np_lock;
        u8 selectq[MAX_NPORTS][2];
        struct cxgbit_list_head cskq;
        u32 mdsl;
        struct kref kref;
        unsigned long flags;
};

struct cxgbit_wr_wait {
        struct completion completion;
        int ret;
};

enum cxgbit_csk_state {
        CSK_STATE_IDLE = 0,
        CSK_STATE_LISTEN,
        CSK_STATE_CONNECTING,
        CSK_STATE_ESTABLISHED,
        CSK_STATE_ABORTING,
        CSK_STATE_CLOSING,
        CSK_STATE_MORIBUND,
        CSK_STATE_DEAD,
};

enum cxgbit_csk_flags {
        CSK_TX_DATA_SENT = 0,
        CSK_LOGIN_PDU_DONE,
        CSK_LOGIN_DONE,
        CSK_DDP_ENABLE,
        CSK_ABORT_RPL_WAIT,
};

struct cxgbit_sock_common {
        struct cxgbit_device *cdev;
        struct sockaddr_storage local_addr;
        struct sockaddr_storage remote_addr;
        struct cxgbit_wr_wait wr_wait;
        enum cxgbit_csk_state state;
        unsigned long flags;
};

struct cxgbit_np {
        struct cxgbit_sock_common com;
        wait_queue_head_t accept_wait;
        struct iscsi_np *np;
        struct completion accept_comp;
        struct list_head np_accept_list;
        /* np accept lock */
        spinlock_t np_accept_lock;
        struct kref kref;
        unsigned int stid;
};

struct cxgbit_sock {
        struct cxgbit_sock_common com;
        struct cxgbit_np *cnp;
        struct iscsit_conn *conn;
        struct l2t_entry *l2t;
        struct dst_entry *dst;
        struct list_head list;
        struct sk_buff_head rxq;
        struct sk_buff_head txq;
        struct sk_buff_head ppodq;
        struct sk_buff_head backlogq;
        struct sk_buff_head skbq;
        struct sk_buff *wr_pending_head;
        struct sk_buff *wr_pending_tail;
        struct sk_buff *skb;
        struct sk_buff *lro_skb;
        struct sk_buff *lro_hskb;
        struct list_head accept_node;
        /* socket lock */
        spinlock_t lock;
        wait_queue_head_t waitq;
        bool lock_owner;
        struct kref kref;
        u32 max_iso_npdu;
        u32 wr_cred;
        u32 wr_una_cred;
        u32 wr_max_cred;
        u32 snd_una;
        u32 tid;
        u32 snd_nxt;
        u32 rcv_nxt;
        u32 smac_idx;
        u32 tx_chan;
        u32 mtu;
        u32 write_seq;
        u32 rx_credits;
        u32 snd_win;
        u32 rcv_win;
        u16 mss;
        u16 emss;
        u16 plen;
        u16 rss_qid;
        u16 txq_idx;
        u16 ctrlq_idx;
        u8 tos;
        u8 port_id;
#define CXGBIT_SUBMODE_HCRC 0x1
#define CXGBIT_SUBMODE_DCRC 0x2
        u8 submode;
#ifdef CONFIG_CHELSIO_T4_DCB
        u8 dcb_priority;
#endif
        u8 snd_wscale;
};

void _cxgbit_free_cdev(struct kref *kref);
void _cxgbit_free_csk(struct kref *kref);
void _cxgbit_free_cnp(struct kref *kref);

static inline void cxgbit_get_cdev(struct cxgbit_device *cdev)
{
        kref_get(&cdev->kref);
}

static inline void cxgbit_put_cdev(struct cxgbit_device *cdev)
{
        kref_put(&cdev->kref, _cxgbit_free_cdev);
}

static inline void cxgbit_get_csk(struct cxgbit_sock *csk)
{
        kref_get(&csk->kref);
}

static inline void cxgbit_put_csk(struct cxgbit_sock *csk)
{
        kref_put(&csk->kref, _cxgbit_free_csk);
}

static inline void cxgbit_get_cnp(struct cxgbit_np *cnp)
{
        kref_get(&cnp->kref);
}

static inline void cxgbit_put_cnp(struct cxgbit_np *cnp)
{
        kref_put(&cnp->kref, _cxgbit_free_cnp);
}

static inline void cxgbit_sock_reset_wr_list(struct cxgbit_sock *csk)
{
        csk->wr_pending_tail = NULL;
        csk->wr_pending_head = NULL;
}

static inline struct sk_buff *cxgbit_sock_peek_wr(const struct cxgbit_sock *csk)
{
        return csk->wr_pending_head;
}

static inline void
cxgbit_sock_enqueue_wr(struct cxgbit_sock *csk, struct sk_buff *skb)
{
        cxgbit_skcb_tx_wr_next(skb) = NULL;

        skb_get(skb);

        if (!csk->wr_pending_head)
                csk->wr_pending_head = skb;
        else
                cxgbit_skcb_tx_wr_next(csk->wr_pending_tail) = skb;
        csk->wr_pending_tail = skb;
}

static inline struct sk_buff *cxgbit_sock_dequeue_wr(struct cxgbit_sock *csk)
{
        struct sk_buff *skb = csk->wr_pending_head;

        if (likely(skb)) {
                csk->wr_pending_head = cxgbit_skcb_tx_wr_next(skb);
                cxgbit_skcb_tx_wr_next(skb) = NULL;
        }
        return skb;
}

typedef void (*cxgbit_cplhandler_func)(struct cxgbit_device *,
                                       struct sk_buff *);

int cxgbit_setup_np(struct iscsi_np *, struct sockaddr_storage *);
int cxgbit_setup_conn_digest(struct cxgbit_sock *);
int cxgbit_accept_np(struct iscsi_np *, struct iscsit_conn *);
void cxgbit_free_np(struct iscsi_np *);
void cxgbit_abort_conn(struct cxgbit_sock *csk);
void cxgbit_free_conn(struct iscsit_conn *);
extern cxgbit_cplhandler_func cxgbit_cplhandlers[NUM_CPL_CMDS];
int cxgbit_get_login_rx(struct iscsit_conn *, struct iscsi_login *);
int cxgbit_rx_data_ack(struct cxgbit_sock *);
int cxgbit_l2t_send(struct cxgbit_device *, struct sk_buff *,
                    struct l2t_entry *);
void cxgbit_push_tx_frames(struct cxgbit_sock *);
int cxgbit_put_login_tx(struct iscsit_conn *, struct iscsi_login *, u32);
int cxgbit_xmit_pdu(struct iscsit_conn *, struct iscsit_cmd *,
                    struct iscsi_datain_req *, const void *, u32);
void cxgbit_get_r2t_ttt(struct iscsit_conn *, struct iscsit_cmd *,
                        struct iscsi_r2t *);
u32 cxgbit_send_tx_flowc_wr(struct cxgbit_sock *);
int cxgbit_ofld_send(struct cxgbit_device *, struct sk_buff *);
void cxgbit_get_rx_pdu(struct iscsit_conn *);
int cxgbit_validate_params(struct iscsit_conn *);
struct cxgbit_device *cxgbit_find_device(struct net_device *, u8 *);

/* DDP */
int cxgbit_ddp_init(struct cxgbit_device *);
int cxgbit_setup_conn_pgidx(struct cxgbit_sock *, u32);
int cxgbit_reserve_ttt(struct cxgbit_sock *, struct iscsit_cmd *);
void cxgbit_unmap_cmd(struct iscsit_conn *, struct iscsit_cmd *);

static inline
struct cxgbi_ppm *cdev2ppm(struct cxgbit_device *cdev)
{
        return (struct cxgbi_ppm *)(*cdev->lldi.iscsi_ppm);
}
#endif /* __CXGBIT_H__ */