lcs.c

LINUX 2.6.17.4的源码

/*
 *  linux/drivers/s390/net/lcs.c
 *
 *  Linux for S/390 Lan Channel Station Network Driver
 *
 *  Copyright (C)  1999-2001 IBM Deutschland Entwicklung GmbH,
 *			     IBM Corporation
 *    Author(s): Original Code written by
 *			  DJ Barrow ([e-mail],[e-mail])
 *		 Rewritten by
 *			  Frank Pavlic ([e-mail]) and
 *		 	  Martin Schwidefsky <[e-mail]>
 *
 * 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.
 */

#include <linux/module.h>
#include <linux/if.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/trdevice.h>
#include <linux/fddidevice.h>
#include <linux/inetdevice.h>
#include <linux/in.h>
#include <linux/igmp.h>
#include <linux/delay.h>
#include <net/arp.h>
#include <net/ip.h>

#include <asm/debug.h>
#include <asm/idals.h>
#include <asm/timex.h>
#include <linux/device.h>
#include <asm/ccwgroup.h>

#include "lcs.h"
#include "cu3088.h"


#if !defined(CONFIG_NET_ETHERNET) && \
    !defined(CONFIG_TR) && !defined(CONFIG_FDDI)
#error Cannot compile lcs.c without some net devices switched on.
#endif

/**
 * initialization string for output
 */

static char version[] __initdata = "LCS driver";
static char debug_buffer[255];

/**
 * Some prototypes.
 */
static void lcs_tasklet(unsigned long);
static void lcs_start_kernel_thread(struct lcs_card *card);
static void lcs_get_frames_cb(struct lcs_channel *, struct lcs_buffer *);
static int lcs_send_delipm(struct lcs_card *, struct lcs_ipm_list *);
static int lcs_recovery(void *ptr);

/**
 * Debug Facility Stuff
 */
static debug_info_t *lcs_dbf_setup;
static debug_info_t *lcs_dbf_trace;

/**
 *  LCS Debug Facility functions
 */
static void
lcs_unregister_debug_facility(void)
{
	if (lcs_dbf_setup)
		debug_unregister(lcs_dbf_setup);
	if (lcs_dbf_trace)
		debug_unregister(lcs_dbf_trace);
}

static int
lcs_register_debug_facility(void)
{
	lcs_dbf_setup = debug_register("lcs_setup", 2, 1, 8);
	lcs_dbf_trace = debug_register("lcs_trace", 2, 2, 8);
	if (lcs_dbf_setup == NULL || lcs_dbf_trace == NULL) {
		PRINT_ERR("Not enough memory for debug facility.\n");
		lcs_unregister_debug_facility();
		return -ENOMEM;
	}
	debug_register_view(lcs_dbf_setup, &debug_hex_ascii_view);
	debug_set_level(lcs_dbf_setup, 2);
	debug_register_view(lcs_dbf_trace, &debug_hex_ascii_view);
	debug_set_level(lcs_dbf_trace, 2);
	return 0;
}

/**
 * Allocate io buffers.
 */
static int
lcs_alloc_channel(struct lcs_channel *channel)
{
	int cnt;

	LCS_DBF_TEXT(2, setup, "ichalloc");
	for (cnt = 0; cnt < LCS_NUM_BUFFS; cnt++) {
		/* alloc memory fo iobuffer */
		channel->iob[cnt].data =
			kzalloc(LCS_IOBUFFERSIZE, GFP_DMA | GFP_KERNEL);
		if (channel->iob[cnt].data == NULL)
			break;
		channel->iob[cnt].state = BUF_STATE_EMPTY;
	}
	if (cnt < LCS_NUM_BUFFS) {
		/* Not all io buffers could be allocated. */
		LCS_DBF_TEXT(2, setup, "echalloc");
		while (cnt-- > 0)
			kfree(channel->iob[cnt].data);
		return -ENOMEM;
	}
	return 0;
}

/**
 * Free io buffers.
 */
static void
lcs_free_channel(struct lcs_channel *channel)
{
	int cnt;

	LCS_DBF_TEXT(2, setup, "ichfree");
	for (cnt = 0; cnt < LCS_NUM_BUFFS; cnt++) {
		kfree(channel->iob[cnt].data);
		channel->iob[cnt].data = NULL;
	}
}

/*
 * Cleanup channel.
 */
static void
lcs_cleanup_channel(struct lcs_channel *channel)
{
	LCS_DBF_TEXT(3, setup, "cleanch");
	/* Kill write channel tasklets. */
	tasklet_kill(&channel->irq_tasklet);
	/* Free channel buffers. */
	lcs_free_channel(channel);
}

/**
 * LCS free memory for card and channels.
 */
static void
lcs_free_card(struct lcs_card *card)
{
	LCS_DBF_TEXT(2, setup, "remcard");
	LCS_DBF_HEX(2, setup, &card, sizeof(void*));
	kfree(card);
}

/**
 * LCS alloc memory for card and channels
 */
static struct lcs_card *
lcs_alloc_card(void)
{
	struct lcs_card *card;
	int rc;

	LCS_DBF_TEXT(2, setup, "alloclcs");

	card = kzalloc(sizeof(struct lcs_card), GFP_KERNEL | GFP_DMA);
	if (card == NULL)
		return NULL;
	card->lan_type = LCS_FRAME_TYPE_AUTO;
	card->pkt_seq = 0;
	card->lancmd_timeout = LCS_LANCMD_TIMEOUT_DEFAULT;
	/* Allocate io buffers for the read channel. */
	rc = lcs_alloc_channel(&card->read);
	if (rc){
		LCS_DBF_TEXT(2, setup, "iccwerr");
		lcs_free_card(card);
		return NULL;
	}
	/* Allocate io buffers for the write channel. */
	rc = lcs_alloc_channel(&card->write);
	if (rc) {
		LCS_DBF_TEXT(2, setup, "iccwerr");
		lcs_cleanup_channel(&card->read);
		lcs_free_card(card);
		return NULL;
	}

#ifdef CONFIG_IP_MULTICAST
	INIT_LIST_HEAD(&card->ipm_list);
#endif
	LCS_DBF_HEX(2, setup, &card, sizeof(void*));
	return card;
}

/*
 * Setup read channel.
 */
static void
lcs_setup_read_ccws(struct lcs_card *card)
{
	int cnt;

	LCS_DBF_TEXT(2, setup, "ireadccw");
	/* Setup read ccws. */
	memset(card->read.ccws, 0, sizeof (struct ccw1) * (LCS_NUM_BUFFS + 1));
	for (cnt = 0; cnt < LCS_NUM_BUFFS; cnt++) {
		card->read.ccws[cnt].cmd_code = LCS_CCW_READ;
		card->read.ccws[cnt].count = LCS_IOBUFFERSIZE;
		card->read.ccws[cnt].flags =
			CCW_FLAG_CC | CCW_FLAG_SLI | CCW_FLAG_PCI;
		/*
		 * Note: we have allocated the buffer with GFP_DMA, so
		 * we do not need to do set_normalized_cda.
		 */
		card->read.ccws[cnt].cda =
			(__u32) __pa(card->read.iob[cnt].data);
		((struct lcs_header *)
		 card->read.iob[cnt].data)->offset = LCS_ILLEGAL_OFFSET;
		card->read.iob[cnt].callback = lcs_get_frames_cb;
		card->read.iob[cnt].state = BUF_STATE_READY;
		card->read.iob[cnt].count = LCS_IOBUFFERSIZE;
	}
	card->read.ccws[0].flags &= ~CCW_FLAG_PCI;
	card->read.ccws[LCS_NUM_BUFFS - 1].flags &= ~CCW_FLAG_PCI;
	card->read.ccws[LCS_NUM_BUFFS - 1].flags |= CCW_FLAG_SUSPEND;
	/* Last ccw is a tic (transfer in channel). */
	card->read.ccws[LCS_NUM_BUFFS].cmd_code = LCS_CCW_TRANSFER;
	card->read.ccws[LCS_NUM_BUFFS].cda =
		(__u32) __pa(card->read.ccws);
	/* Setg initial state of the read channel. */
	card->read.state = CH_STATE_INIT;

	card->read.io_idx = 0;
	card->read.buf_idx = 0;
}

static void
lcs_setup_read(struct lcs_card *card)
{
	LCS_DBF_TEXT(3, setup, "initread");

	lcs_setup_read_ccws(card);
	/* Initialize read channel tasklet. */
	card->read.irq_tasklet.data = (unsigned long) &card->read;
	card->read.irq_tasklet.func = lcs_tasklet;
	/* Initialize waitqueue. */
	init_waitqueue_head(&card->read.wait_q);
}

/*
 * Setup write channel.
 */
static void
lcs_setup_write_ccws(struct lcs_card *card)
{
	int cnt;

	LCS_DBF_TEXT(3, setup, "iwritccw");
	/* Setup write ccws. */
	memset(card->write.ccws, 0, sizeof(struct ccw1) * LCS_NUM_BUFFS + 1);
	for (cnt = 0; cnt < LCS_NUM_BUFFS; cnt++) {
		card->write.ccws[cnt].cmd_code = LCS_CCW_WRITE;
		card->write.ccws[cnt].count = 0;
		card->write.ccws[cnt].flags =
			CCW_FLAG_SUSPEND | CCW_FLAG_CC | CCW_FLAG_SLI;
		/*
		 * Note: we have allocated the buffer with GFP_DMA, so
		 * we do not need to do set_normalized_cda.
		 */
		card->write.ccws[cnt].cda =
			(__u32) __pa(card->write.iob[cnt].data);
	}
	/* Last ccw is a tic (transfer in channel). */
	card->write.ccws[LCS_NUM_BUFFS].cmd_code = LCS_CCW_TRANSFER;
	card->write.ccws[LCS_NUM_BUFFS].cda =
		(__u32) __pa(card->write.ccws);
	/* Set initial state of the write channel. */
	card->read.state = CH_STATE_INIT;

	card->write.io_idx = 0;
	card->write.buf_idx = 0;
}

static void
lcs_setup_write(struct lcs_card *card)
{
	LCS_DBF_TEXT(3, setup, "initwrit");

	lcs_setup_write_ccws(card);
	/* Initialize write channel tasklet. */
	card->write.irq_tasklet.data = (unsigned long) &card->write;
	card->write.irq_tasklet.func = lcs_tasklet;
	/* Initialize waitqueue. */
	init_waitqueue_head(&card->write.wait_q);
}

static void
lcs_set_allowed_threads(struct lcs_card *card, unsigned long threads)
{
	unsigned long flags;

	spin_lock_irqsave(&card->mask_lock, flags);
	card->thread_allowed_mask = threads;
	spin_unlock_irqrestore(&card->mask_lock, flags);
	wake_up(&card->wait_q);
}
static inline int
lcs_threads_running(struct lcs_card *card, unsigned long threads)
{
        unsigned long flags;
        int rc = 0;

	spin_lock_irqsave(&card->mask_lock, flags);
        rc = (card->thread_running_mask & threads);
	spin_unlock_irqrestore(&card->mask_lock, flags);
        return rc;
}

static int
lcs_wait_for_threads(struct lcs_card *card, unsigned long threads)
{
        return wait_event_interruptible(card->wait_q,
                        lcs_threads_running(card, threads) == 0);
}

static inline int
lcs_set_thread_start_bit(struct lcs_card *card, unsigned long thread)
{
        unsigned long flags;

	spin_lock_irqsave(&card->mask_lock, flags);
        if ( !(card->thread_allowed_mask & thread) ||
              (card->thread_start_mask & thread) ) {
                spin_unlock_irqrestore(&card->mask_lock, flags);
                return -EPERM;
        }
        card->thread_start_mask |= thread;
	spin_unlock_irqrestore(&card->mask_lock, flags);
        return 0;
}

static void
lcs_clear_thread_running_bit(struct lcs_card *card, unsigned long thread)
{
        unsigned long flags;

	spin_lock_irqsave(&card->mask_lock, flags);
        card->thread_running_mask &= ~thread;
	spin_unlock_irqrestore(&card->mask_lock, flags);
        wake_up(&card->wait_q);
}

static inline int
__lcs_do_run_thread(struct lcs_card *card, unsigned long thread)
{
        unsigned long flags;
        int rc = 0;

	spin_lock_irqsave(&card->mask_lock, flags);
        if (card->thread_start_mask & thread){
                if ((card->thread_allowed_mask & thread) &&
                    !(card->thread_running_mask & thread)){
                        rc = 1;
                        card->thread_start_mask &= ~thread;
                        card->thread_running_mask |= thread;
                } else
                        rc = -EPERM;
        }
	spin_unlock_irqrestore(&card->mask_lock, flags);
        return rc;
}

static int
lcs_do_run_thread(struct lcs_card *card, unsigned long thread)
{
        int rc = 0;
        wait_event(card->wait_q,
                   (rc = __lcs_do_run_thread(card, thread)) >= 0);
        return rc;
}

static int
lcs_do_start_thread(struct lcs_card *card, unsigned long thread)
{
        unsigned long flags;
        int rc = 0;

	spin_lock_irqsave(&card->mask_lock, flags);
        LCS_DBF_TEXT_(4, trace, "  %02x%02x%02x",
                        (u8) card->thread_start_mask,
                        (u8) card->thread_allowed_mask,
                        (u8) card->thread_running_mask);
        rc = (card->thread_start_mask & thread);
	spin_unlock_irqrestore(&card->mask_lock, flags);
        return rc;
}

/**
 * Initialize channels,card and state machines.
 */
static void
lcs_setup_card(struct lcs_card *card)
{
	LCS_DBF_TEXT(2, setup, "initcard");
	LCS_DBF_HEX(2, setup, &card, sizeof(void*));

	lcs_setup_read(card);
	lcs_setup_write(card);
	/* Set cards initial state. */
	card->state = DEV_STATE_DOWN;
	card->tx_buffer = NULL;
	card->tx_emitted = 0;

	init_waitqueue_head(&card->wait_q);
	spin_lock_init(&card->lock);
	spin_lock_init(&card->ipm_lock);
	spin_lock_init(&card->mask_lock);
#ifdef CONFIG_IP_MULTICAST
	INIT_LIST_HEAD(&card->ipm_list);
#endif
	INIT_LIST_HEAD(&card->lancmd_waiters);
}

static inline void
lcs_clear_multicast_list(struct lcs_card *card)
{
#ifdef	CONFIG_IP_MULTICAST
	struct lcs_ipm_list *ipm;
	unsigned long flags;

	/* Free multicast list. */
	LCS_DBF_TEXT(3, setup, "clmclist");
	spin_lock_irqsave(&card->ipm_lock, flags);
	while (!list_empty(&card->ipm_list)){
		ipm = list_entry(card->ipm_list.next,
				 struct lcs_ipm_list, list);
		list_del(&ipm->list);
		if (ipm->ipm_state != LCS_IPM_STATE_SET_REQUIRED){
			spin_unlock_irqrestore(&card->ipm_lock, flags);
			lcs_send_delipm(card, ipm);
			spin_lock_irqsave(&card->ipm_lock, flags);
		}
		kfree(ipm);
	}
	spin_unlock_irqrestore(&card->ipm_lock, flags);
#endif
}
/**
 * Cleanup channels,card and state machines.
 */
static void
lcs_cleanup_card(struct lcs_card *card)
{

	LCS_DBF_TEXT(3, setup, "cleancrd");
	LCS_DBF_HEX(2,setup,&card,sizeof(void*));

	if (card->dev != NULL)
		free_netdev(card->dev);
	/* Cleanup channels. */
	lcs_cleanup_channel(&card->write);
	lcs_cleanup_channel(&card->read);
}

/**
 * Start channel.
 */
static int
lcs_start_channel(struct lcs_channel *channel)
{
	unsigned long flags;
	int rc;

	LCS_DBF_TEXT_(4,trace,"ssch%s", channel->ccwdev->dev.bus_id);
	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
	rc = ccw_device_start(channel->ccwdev,
			      channel->ccws + channel->io_idx, 0, 0,
			      DOIO_DENY_PREFETCH | DOIO_ALLOW_SUSPEND);
	if (rc == 0)
		channel->state = CH_STATE_RUNNING;
	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
	if (rc) {
		LCS_DBF_TEXT_(4,trace,"essh%s", channel->ccwdev->dev.bus_id);
		PRINT_ERR("Error in starting channel, rc=%d!\n", rc);
	}
	return rc;
}

static int
lcs_clear_channel(struct lcs_channel *channel)
{
	unsigned long flags;
	int rc;

	LCS_DBF_TEXT(4,trace,"clearch");
	LCS_DBF_TEXT_(4,trace,"%s", channel->ccwdev->dev.bus_id);
	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
	rc = ccw_device_clear(channel->ccwdev, (addr_t) channel);
	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
	if (rc) {
		LCS_DBF_TEXT_(4,trace,"ecsc%s", channel->ccwdev->dev.bus_id);
		return rc;
	}
	wait_event(channel->wait_q, (channel->state == CH_STATE_CLEARED));
	channel->state = CH_STATE_STOPPED;
	return rc;
}


/**
 * Stop channel.
 */
static int
lcs_stop_channel(struct lcs_channel *channel)
{
	unsigned long flags;
	int rc;

	if (channel->state == CH_STATE_STOPPED)
		return 0;
	LCS_DBF_TEXT(4,trace,"haltsch");
	LCS_DBF_TEXT_(4,trace,"%s", channel->ccwdev->dev.bus_id);
	channel->state = CH_STATE_INIT;
	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
	rc = ccw_device_halt(channel->ccwdev, (addr_t) channel);
	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
	if (rc) {
		LCS_DBF_TEXT_(4,trace,"ehsc%s", channel->ccwdev->dev.bus_id);
		return rc;
	}
	/* Asynchronous halt initialted. Wait for its completion. */
	wait_event(channel->wait_q, (channel->state == CH_STATE_HALTED));
	lcs_clear_channel(channel);
	return 0;
}

/**
 * start read and write channel
 */
static int
lcs_start_channels(struct lcs_card *card)
{
	int rc;

	LCS_DBF_TEXT(2, trace, "chstart");
	/* start read channel */
	rc = lcs_start_channel(&card->read);
	if (rc)
		return rc;
	/* start write channel */
	rc = lcs_start_channel(&card->write);
	if (rc)
		lcs_stop_channel(&card->read);
	return rc;
}

/**
 * stop read and write channel
 */
static int
lcs_stop_channels(struct lcs_card *card)
{
	LCS_DBF_TEXT(2, trace, "chhalt");
	lcs_stop_channel(&card->read);
	lcs_stop_channel(&card->write);
	return 0;
}