/*
 * This file is part of the Chelsio T3 Ethernet driver for Linux.
 *
 * Copyright (C) 2003-2009 Chelsio Communications.  All rights reserved.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the LICENSE file included in this
 * release for licensing terms and conditions.
 */

#ifndef _CXGB3_OFFLOAD_H
#define _CXGB3_OFFLOAD_H

#include <linux/list.h>
#include <linux/skbuff.h>
#include <net/offload.h>

#include "tcb.h"
#include "l2t.h"

#include "t3cdev.h"
#include "t3_cpl.h"

struct adapter;
extern struct list_head adapter_list;
extern rwlock_t adapter_list_lock;

void cxgb3_offload_init(void);
void cxgb3_offload_exit(void);

void cxgb3_adapter_ofld(struct adapter *adapter);
void cxgb3_adapter_unofld(struct adapter *adapter);
int cxgb3_offload_activate(struct adapter *adapter);
void cxgb3_offload_deactivate(struct adapter *adapter);

int offload_devices_read_proc(char *buf, char **start, off_t offset,
			      int length, int *eof, void *data);

int cxgb3_ofld_recv(struct t3cdev *dev, struct sk_buff **skb, int n);

void cxgb3_set_dummy_ops(struct t3cdev *dev);

struct t3cdev *dev2t3cdev(struct net_device *dev);

/*
 * Client registration.  Users of T3 driver must register themselves.
 * The T3 driver will call the add function of every client for each T3
 * adapter activated, passing up the t3cdev ptr.  Each client fills out an
 * array of callback functions to process CPL messages.
 */

void cxgb3_register_client(struct cxgb3_client *client);
void cxgb3_unregister_client(struct cxgb3_client *client);
void cxgb3_add_clients(struct t3cdev *tdev);
void cxgb3_remove_clients(struct t3cdev *tdev);
void cxgb3_err_notify(struct t3cdev *tdev, u32 status, u32 error);

typedef int (*cxgb3_cpl_handler_func)(struct t3cdev *dev,
				      struct sk_buff *skb, void *ctx);
enum {
	OFFLOAD_STATUS_UP,
	OFFLOAD_STATUS_DOWN,
	OFFLOAD_DB_FULL,
	OFFLOAD_DB_EMPTY,
	OFFLOAD_DB_DROP
};

struct cxgb3_client {
	char 			*name;
	void 			(*add) (struct t3cdev *);
	void 			(*remove) (struct t3cdev *);
	cxgb3_cpl_handler_func 	*handlers;
	int			(*redirect)(void *ctx, struct dst_entry *old,
					    struct dst_entry *new,
					    struct l2t_entry *l2t);
	struct list_head	client_list;

	/*
	 * End of legacy cxgb3_client data structure.  No part of the above
	 * may be changed.
	 */

	/*
	 * Start of t3_tom-extended cxgb3_client data structure.  Only t3_tom
	 * has these fields ...
	 */
	/* Added in kernel.org */
	void (*event_handler)(struct t3cdev *tdev, u32 status, u32 error);
	int			(*set_offload_policy)(struct net_device *,
						      const struct ofld_policy_file *,
						      size_t);
};

/*
 * TID allocation services.
 */
int cxgb3_alloc_atid(struct t3cdev *dev, struct cxgb3_client *client,
		     void *ctx);
int cxgb3_alloc_stid(struct t3cdev *dev, struct cxgb3_client *client,
		     void *ctx);
void *cxgb3_free_atid(struct t3cdev *dev, int atid);
void cxgb3_free_stid(struct t3cdev *dev, int stid);
void cxgb3_insert_tid(struct t3cdev *dev, struct cxgb3_client *client,
		      void *ctx,
	unsigned int tid);
void cxgb3_queue_tid_release(struct t3cdev *dev, unsigned int tid);
void cxgb3_remove_tid(struct t3cdev *dev, void *ctx, unsigned int tid);

struct t3c_tid_entry {
	struct cxgb3_client 	*client;
	void 			*ctx;
};

/* CPL message priority levels */
enum {
	CPL_PRIORITY_DATA = 0,     /* data messages */
	CPL_PRIORITY_SETUP = 1,	   /* connection setup messages */
	CPL_PRIORITY_TEARDOWN = 0, /* connection teardown messages */
	CPL_PRIORITY_LISTEN = 1,   /* listen start/stop messages */
	CPL_PRIORITY_ACK = 1,      /* RX ACK messages */
	CPL_PRIORITY_CONTROL = 1   /* offload control messages */
};

/* Flags for return value of CPL message handlers */
enum {
	CPL_RET_BUF_DONE = 1,   // buffer processing done, buffer may be freed
	CPL_RET_BAD_MSG = 2,    // bad CPL message (e.g., unknown opcode)
	CPL_RET_UNKNOWN_TID = 4	// unexpected unknown TID
};

typedef int (*cpl_handler_func)(struct t3cdev *dev, struct sk_buff *skb);

/*
 * Returns a pointer to the first byte of the CPL header in an sk_buff that
 * contains a CPL message.
 */
static inline void *cplhdr(struct sk_buff *skb)
{
	return skb->data;
}

void t3_register_cpl_handler(unsigned int opcode, cpl_handler_func h);

union listen_entry {
	struct t3c_tid_entry t3c_tid;
	union listen_entry *next;
};

union active_open_entry {
	struct t3c_tid_entry t3c_tid;
	union active_open_entry *next;
};

/*
 * Holds the size, base address, free list start, etc of the TID, server TID,
 * and active-open TID tables for a offload device.
 * The tables themselves are allocated dynamically.
 */
struct tid_info {
	struct t3c_tid_entry *tid_tab;
	unsigned int ntids;
	atomic_t tids_in_use;

	union listen_entry *stid_tab;
	unsigned int nstids;
	unsigned int stid_base;

	union active_open_entry *atid_tab;
	unsigned int natids;
	unsigned int atid_base;

	/*
	 * The following members are accessed R/W so we put them in their own
	 * cache lines.
	 *
	 * XXX We could combine the atid fields above with the lock here since
	 * atids are use once (unlike other tids).  OTOH the above fields are
	 * usually in cache due to tid_tab.
	 */
	spinlock_t atid_lock ____cacheline_aligned_in_smp;
	union active_open_entry *afree;
	unsigned int atids_in_use;

	spinlock_t stid_lock ____cacheline_aligned;
	union listen_entry *sfree;
	unsigned int stids_in_use;
};

struct t3c_data {
	struct list_head list_node;
	struct t3cdev *dev;
	unsigned int tx_max_chunk;  /* max payload for TX_DATA */
	unsigned int max_wrs;       /* max in-flight WRs per connection */
	unsigned int nmtus;
	const unsigned short *mtus;
	struct tid_info tid_maps;

	struct t3c_tid_entry *tid_release_list;
	spinlock_t tid_release_lock;
	struct work_struct tid_release_task;
};

/*
 * t3cdev -> t3c_data accessor
 */
#define T3C_DATA(dev) (*(struct t3c_data **)&(dev)->l4opt)

#endif