iucv.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

/* 
 * $Id$
 *
 * IUCV network driver
 *
 * Copyright (C) 2001 IBM Deutschland Entwicklung GmbH, IBM Corporation
 * Author(s):
 *    Original source:
 *      Alan Altmark ([e-mail])  Sept. 2000
 *      Xenia Tkatschow ([e-mail])
 *    2Gb awareness and general cleanup:
 *      Fritz Elfert ([e-mail], [e-mail])
 *
 * Documentation used:
 *    The original source
 *    CP Programming Service, IBM document # SC24-5760
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * 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
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * RELEASE-TAG: IUCV lowlevel driver $Revision$
 *
 */

#include <linux/module.h>
#include <linux/config.h>

#include <linux/version.h>
#include <linux/spinlock.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/tqueue.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <asm/atomic.h>
#include "iucv.h"
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/s390_ext.h>
#include <asm/ebcdic.h>

#undef DEBUG

/* FLAGS:
 * All flags are defined in the field IPFLAGS1 of each function
 * and can be found in CP Programming Services.
 * IPSRCCLS - Indicates you have specified a source class
 * IPFGMCL  - Indicates you have specified a target class
 * IPFGPID  - Indicates you have specified a pathid
 * IPFGMID  - Indicates you have specified a message ID
 * IPANSLST - Indicates that you are using an address list for
 *            reply data
 * IPBUFLST - Indicates that you are using an address list for
 *            message data
 */

#define IPSRCCLS 	0x01
#define IPFGMCL         0x01
#define IPFGPID         0x02
#define IPFGMID         0x04
#define IPANSLST        0x08
#define IPBUFLST        0x40

/* General IUCV interrupt structure */
typedef struct {
	__u16 ippathid;
	__u8  res1;
	__u8  iptype;
	__u32 res2;
	__u8  ipvmid[8];
	__u8  res3[24];
} iucv_GeneralInterrupt;

static iucv_GeneralInterrupt *iucv_external_int_buffer;

/* Spin Lock declaration */

static spinlock_t iucv_lock = SPIN_LOCK_UNLOCKED;

/***************INTERRUPT HANDLING ***************/

typedef struct {
	struct list_head queue;
	iucv_GeneralInterrupt data;
} iucv_irqdata;

struct list_head  iucv_irq_queue;
static spinlock_t iucv_irq_queue_lock = SPIN_LOCK_UNLOCKED;

struct tq_struct  iucv_tq;

static atomic_t   iucv_bh_scheduled = ATOMIC_INIT (0);

/*
 *Internal function prototypes
 */
static void iucv_bh_handler(void);
static void iucv_irq_handler(struct pt_regs *, __u16);

/************ FUNCTION ID'S ****************************/

#define ACCEPT          10
#define CONNECT         11
#define DECLARE_BUFFER  12
#define PURGE           9
#define QUERY           0
#define QUIESCE         13
#define RECEIVE         5
#define REJECT          8
#define REPLY           6
#define RESUME          14
#define RETRIEVE_BUFFER 2
#define SEND            4
#define SETMASK         16
#define SEVER           15

/**
 * Structure: handler
 * members: list - list management.
 *          structure: id
 *             userid - 8 char array of machine identification
 *             user_data - 16 char array for user identification
 *             mask - 24 char array used to compare the 2 previous
 *          interrupt_table - vector of interrupt functions.
 *          pgm_data -  ulong, application data that is passed
 *                      to the interrupt handlers
*/
typedef struct handler_t {
	struct list_head list;
	struct {
		__u8 userid[8];
		__u8 user_data[16];
		__u8 mask[24];
	}                    id;
	iucv_interrupt_ops_t *interrupt_table;
	void                 *pgm_data;
} handler;

/**
 * iucv_handler_table: List of registered handlers.
 */
static struct list_head iucv_handler_table;

/**
 * iucv_pathid_table: an array of *handler pointing into
 *                    iucv_handler_table for fast indexing by pathid;
 */
static handler **iucv_pathid_table;

static unsigned long max_connections;

/**
 * declare_flag: is 0 when iucv_declare_buffer has not been called
 */
static int declare_flag;

/****************FIVE 40-BYTE PARAMETER STRUCTURES******************/
/* Data struct 1: iparml_control
 * Used for iucv_accept
 *          iucv_connect
 *          iucv_quiesce
 *          iucv_resume
 *          iucv_sever
 *          iucv_retrieve_buffer
 * Data struct 2: iparml_dpl     (data in parameter list)
 * Used for iucv_send_prmmsg
 *          iucv_send2way_prmmsg
 *          iucv_send2way_prmmsg_array
 *          iucv_reply_prmmsg
 * Data struct 3: iparml_db       (data in a buffer)
 * Used for iucv_receive
 *          iucv_receive_array
 *          iucv_reject
 *          iucv_reply
 *          iucv_reply_array
 *          iucv_send
 *          iucv_send_array
 *          iucv_send2way
 *          iucv_send2way_array
 *          iucv_declare_buffer
 * Data struct 4: iparml_purge
 * Used for iucv_purge
 *          iucv_query
 * Data struct 5: iparml_set_mask
 * Used for iucv_set_mask
 */

typedef struct {
	__u16 ippathid;
	__u8  ipflags1;
	__u8  iprcode;
	__u16 ipmsglim;
	__u16 res1;
	__u8  ipvmid[8];
	__u8  ipuser[16];
	__u8  iptarget[8];
} iparml_control;

typedef struct {
	__u16 ippathid;
	__u8  ipflags1;
	__u8  iprcode;
	__u32 ipmsgid;
	__u32 iptrgcls;
	__u8  iprmmsg[8];
	__u32 ipsrccls;
	__u32 ipmsgtag;
	__u32 ipbfadr2;
	__u32 ipbfln2f;
	__u32 res;
} iparml_dpl;

typedef struct {
	__u16 ippathid;
	__u8  ipflags1;
	__u8  iprcode;
	__u32 ipmsgid;
	__u32 iptrgcls;
	__u32 ipbfadr1;
	__u32 ipbfln1f;
	__u32 ipsrccls;
	__u32 ipmsgtag;
	__u32 ipbfadr2;
	__u32 ipbfln2f;
	__u32 res;
} iparml_db;

typedef struct {
	__u16 ippathid;
	__u8  ipflags1;
	__u8  iprcode;
	__u32 ipmsgid;
	__u8  ipaudit[3];
	__u8  res1[5];
	__u32 res2;
	__u32 ipsrccls;
	__u32 ipmsgtag;
	__u32 res3[3];
} iparml_purge;

typedef struct {
	__u8  ipmask;
	__u8  res1[2];
	__u8  iprcode;
	__u32 res2[9];
} iparml_set_mask;

typedef struct {
	union {
		iparml_control  p_ctrl;
		iparml_dpl      p_dpl;
		iparml_db       p_db;
		iparml_purge    p_purge;
		iparml_set_mask p_set_mask;
	} param;
	atomic_t in_use;
}  __attribute__ ((aligned(8))) iucv_param;
#define PARAM_POOL_SIZE (PAGE_SIZE / sizeof(iucv_param))

static iucv_param * iucv_param_pool;

/*
 * Debugging stuff
 *******************************************************************************/

#ifdef DEBUG

static void
iucv_dumpit(void *buf, int len)
{
	int i;
	__u8 *p = (__u8 *)buf;

	printk(KERN_DEBUG "  ");
	for (i = 0; i < len; i++) {
		if (!(i % 16) && i != 0)
			printk ("\n  ");
		else if (!(i % 4) && i != 0)
			printk (" ");
		printk ("%02X", *p++);
	}
	if (len % 16)
		printk ("\n");
	return;
}
#define iucv_debug(fmt, args...) \
printk(KERN_DEBUG __FUNCTION__ ": " fmt "\n" , ## args);

#else

#define iucv_debug(fmt, args...)
#define iucv_dumpit(buf, len)

#endif

/*
 * Internal functions
 *******************************************************************************/

/**
 * iucv_init - Initialization
 *
 * Allocates and initializes various data structures.
 */
static int
iucv_init(void)
{
	if (iucv_external_int_buffer)
		return 0;

	/* Note: GFP_DMA used used to get memory below 2G */
	iucv_external_int_buffer = kmalloc(sizeof(iucv_GeneralInterrupt),
					   GFP_KERNEL|GFP_DMA);
	if (!iucv_external_int_buffer) {
		printk(KERN_WARNING
		       "%s: Could not allocate external interrupt buffer\n",
		       __FUNCTION__);
		return -ENOMEM;
	}
	memset(iucv_external_int_buffer, 0, sizeof(iucv_GeneralInterrupt));

	/* Initialize parameter pool */
	iucv_param_pool = kmalloc(sizeof(iucv_param) * PARAM_POOL_SIZE,
				  GFP_KERNEL|GFP_DMA);
	if (!iucv_param_pool) {
		printk(KERN_WARNING "%s: Could not allocate param pool\n",
		       __FUNCTION__);
		kfree(iucv_external_int_buffer);
		iucv_external_int_buffer = NULL;
		return -ENOMEM;
	}
	memset(iucv_param_pool, 0, sizeof(iucv_param) * PARAM_POOL_SIZE);

	/* Initialize task queue */
	INIT_LIST_HEAD(&iucv_tq.list);
	iucv_tq.sync = 0;
	iucv_tq.routine = (void *)iucv_bh_handler;

	/* Initialize irq queue */
	INIT_LIST_HEAD(&iucv_irq_queue);

	/* Initialize handler table */
	INIT_LIST_HEAD(&iucv_handler_table);

	return 0;
}

/**
 * grab_param: - Get a parameter buffer from the pre-allocated pool.
 *
 * This function searches for an unused element in the the pre-allocated pool
 * of parameter buffers. If one is found, it marks it "in use" and returns
 * a pointer to it. The calling function is responsible for releasing it
 * when it has finished its usage.
 *
 * Returns: A pointer to iucv_param.
 */
static __inline__ iucv_param *
grab_param(void)
{
	iucv_param *ret;
	static int i = 0;

	while (atomic_compare_and_swap(0, 1, &iucv_param_pool[i].in_use)) {
		i++;
		if (i >= PARAM_POOL_SIZE)
			i = 0;
	}
	ret = &iucv_param_pool[i];
	memset(&ret->param, 0, sizeof(ret->param));
	return ret;
}

/**
 * release_param - Release a parameter buffer.
 * @p: A pointer to a struct iucv_param, previously obtained by calling
 *     grab_param().
 *
 * This function marks the specified parameter buffer "unused".
 */
static __inline__ void
release_param(void *p)
{
	atomic_set(&((iucv_param *)p)->in_use, 0);
}

/**
 * iucv_add_handler: - Add a new handler
 * @new_handler: handle that is being entered into chain.
 *
 * Places new handle on iucv_handler_table, if identical handler is not
 * found.
 *
 * Returns: 0 on success, !0 on failure (handler already in chain).
 */
static int
iucv_add_handler (handler *new)
{
	ulong flags;

	iucv_debug("entering");
	iucv_dumpit(new, sizeof(handler));

	spin_lock_irqsave (&iucv_lock, flags);
	if (!list_empty(&iucv_handler_table)) {
		struct list_head *lh;

		/**
		 * Search list for handler with identical id. If one
		 * is found, the new handler is _not_ added.
		 */
		list_for_each(lh, &iucv_handler_table) {
			handler *h = list_entry(lh, handler, list);
			if (memcmp(&new->id, &h->id, sizeof(h->id)) == 0) {
				iucv_debug("ret 1");
				spin_unlock_irqrestore (&iucv_lock, flags);
				return 1;
			}
		}
	}
	/**
	 * If we get here, no handler was found.
	 */
	INIT_LIST_HEAD(&new->list);
	list_add(&new->list, &iucv_handler_table);
	spin_unlock_irqrestore (&iucv_lock, flags);

	iucv_debug("exiting");
	return 0;
}

/**
 * iucv_remove_handler:
 * @users_handler: handler to be removed
 *
 * Remove handler when application unregisters.
 */
static void
iucv_remove_handler(handler *handler)
{
	unsigned long flags;

	if ((!iucv_pathid_table) || (!handler))
		return;

	iucv_debug("entering");