pcmcia_ioctl.c

来自「linux 内核源代码」· C语言 代码 · 共 807 行 · 第 1/2 页

/*
 * pcmcia_ioctl.c -- ioctl interface for cardmgr and cardctl
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * The initial developer of the original code is David A. Hinds
 * <[e-mail]>.  Portions created by David A. Hinds
 * are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
 *
 * (C) 1999		David A. Hinds
 * (C) 2003 - 2004	Dominik Brodowski
 */

/*
 * This file will go away soon.
 */


#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/major.h>
#include <linux/errno.h>
#include <linux/ioctl.h>
#include <linux/proc_fs.h>
#include <linux/poll.h>
#include <linux/pci.h>
#include <linux/workqueue.h>

#define IN_CARD_SERVICES
#include <pcmcia/cs_types.h>
#include <pcmcia/cs.h>
#include <pcmcia/cistpl.h>
#include <pcmcia/ds.h>
#include <pcmcia/ss.h>

#include "cs_internal.h"
#include "ds_internal.h"

static int major_dev = -1;


/* Device user information */
#define MAX_EVENTS	32
#define USER_MAGIC	0x7ea4
#define CHECK_USER(u) \
    (((u) == NULL) || ((u)->user_magic != USER_MAGIC))

typedef struct user_info_t {
	u_int			user_magic;
	int			event_head, event_tail;
	event_t			event[MAX_EVENTS];
	struct user_info_t	*next;
	struct pcmcia_socket	*socket;
} user_info_t;


#ifdef DEBUG
extern int ds_pc_debug;

#define ds_dbg(lvl, fmt, arg...) do {		\
	if (ds_pc_debug >= lvl)				\
		printk(KERN_DEBUG "ds: " fmt , ## arg);		\
} while (0)
#else
#define ds_dbg(lvl, fmt, arg...) do { } while (0)
#endif

static struct pcmcia_device *get_pcmcia_device(struct pcmcia_socket *s,
						unsigned int function)
{
	struct pcmcia_device *p_dev = NULL;
	unsigned long flags;

	spin_lock_irqsave(&pcmcia_dev_list_lock, flags);
	list_for_each_entry(p_dev, &s->devices_list, socket_device_list) {
		if (p_dev->func == function) {
			spin_unlock_irqrestore(&pcmcia_dev_list_lock, flags);
			return pcmcia_get_dev(p_dev);
		}
	}
	spin_unlock_irqrestore(&pcmcia_dev_list_lock, flags);
	return NULL;
}

/* backwards-compatible accessing of driver --- by name! */

static struct pcmcia_driver *get_pcmcia_driver(dev_info_t *dev_info)
{
	struct device_driver *drv;
	struct pcmcia_driver *p_drv;

	drv = driver_find((char *) dev_info, &pcmcia_bus_type);
	if (!drv)
		return NULL;

	p_drv = container_of(drv, struct pcmcia_driver, drv);

	return (p_drv);
}


#ifdef CONFIG_PROC_FS
static struct proc_dir_entry *proc_pccard = NULL;

static int proc_read_drivers_callback(struct device_driver *driver, void *d)
{
	char **p = d;
	struct pcmcia_driver *p_drv = container_of(driver,
						   struct pcmcia_driver, drv);

	*p += sprintf(*p, "%-24.24s 1 %d\n", p_drv->drv.name,
#ifdef CONFIG_MODULE_UNLOAD
		      (p_drv->owner) ? module_refcount(p_drv->owner) : 1
#else
		      1
#endif
	);
	d = (void *) p;

	return 0;
}

static int proc_read_drivers(char *buf, char **start, off_t pos,
			     int count, int *eof, void *data)
{
	char *p = buf;
	int rc;

	rc = bus_for_each_drv(&pcmcia_bus_type, NULL,
			      (void *) &p, proc_read_drivers_callback);
	if (rc < 0)
		return rc;

	return (p - buf);
}
#endif

/*======================================================================

    These manage a ring buffer of events pending for one user process

======================================================================*/


static int queue_empty(user_info_t *user)
{
    return (user->event_head == user->event_tail);
}

static event_t get_queued_event(user_info_t *user)
{
    user->event_tail = (user->event_tail+1) % MAX_EVENTS;
    return user->event[user->event_tail];
}

static void queue_event(user_info_t *user, event_t event)
{
    user->event_head = (user->event_head+1) % MAX_EVENTS;
    if (user->event_head == user->event_tail)
	user->event_tail = (user->event_tail+1) % MAX_EVENTS;
    user->event[user->event_head] = event;
}

void handle_event(struct pcmcia_socket *s, event_t event)
{
    user_info_t *user;
    for (user = s->user; user; user = user->next)
	queue_event(user, event);
    wake_up_interruptible(&s->queue);
}


/*======================================================================

    bind_request() and bind_device() are merged by now. Register_client()
    is called right at the end of bind_request(), during the driver's
    ->attach() call. Individual descriptions:

    bind_request() connects a socket to a particular client driver.
    It looks up the specified device ID in the list of registered
    drivers, binds it to the socket, and tries to create an instance
    of the device.  unbind_request() deletes a driver instance.

    Bind_device() associates a device driver with a particular socket.
    It is normally called by Driver Services after it has identified
    a newly inserted card.  An instance of that driver will then be
    eligible to register as a client of this socket.

    Register_client() uses the dev_info_t handle to match the
    caller with a socket.  The driver must have already been bound
    to a socket with bind_device() -- in fact, bind_device()
    allocates the client structure that will be used.

======================================================================*/

static int bind_request(struct pcmcia_socket *s, bind_info_t *bind_info)
{
	struct pcmcia_driver *p_drv;
	struct pcmcia_device *p_dev;
	int ret = 0;
	unsigned long flags;

	s = pcmcia_get_socket(s);
	if (!s)
		return -EINVAL;

	ds_dbg(2, "bind_request(%d, '%s')\n", s->sock,
	       (char *)bind_info->dev_info);

	p_drv = get_pcmcia_driver(&bind_info->dev_info);
	if (!p_drv) {
		ret = -EINVAL;
		goto err_put;
	}

	if (!try_module_get(p_drv->owner)) {
		ret = -EINVAL;
		goto err_put_driver;
	}

	spin_lock_irqsave(&pcmcia_dev_list_lock, flags);
        list_for_each_entry(p_dev, &s->devices_list, socket_device_list) {
		if (p_dev->func == bind_info->function) {
			if ((p_dev->dev.driver == &p_drv->drv)) {
				if (p_dev->cardmgr) {
					/* if there's already a device
					 * registered, and it was registered
					 * by userspace before, we need to
					 * return the "instance". */
					spin_unlock_irqrestore(&pcmcia_dev_list_lock, flags);
					bind_info->instance = p_dev;
					ret = -EBUSY;
					goto err_put_module;
				} else {
					/* the correct driver managed to bind
					 * itself magically to the correct
					 * device. */
					spin_unlock_irqrestore(&pcmcia_dev_list_lock, flags);
					p_dev->cardmgr = p_drv;
					ret = 0;
					goto err_put_module;
				}
			} else if (!p_dev->dev.driver) {
				/* there's already a device available where
				 * no device has been bound to yet. So we don't
				 * need to register a device! */
				spin_unlock_irqrestore(&pcmcia_dev_list_lock, flags);
				goto rescan;
			}
		}
	}
	spin_unlock_irqrestore(&pcmcia_dev_list_lock, flags);

	p_dev = pcmcia_device_add(s, bind_info->function);
	if (!p_dev) {
		ret = -EIO;
		goto err_put_module;
	}

rescan:
	p_dev->cardmgr = p_drv;

	/* if a driver is already running, we can abort */
	if (p_dev->dev.driver)
		goto err_put_module;

	/*
	 * Prevent this racing with a card insertion.
	 */
	mutex_lock(&s->skt_mutex);
	ret = bus_rescan_devices(&pcmcia_bus_type);
	mutex_unlock(&s->skt_mutex);
	if (ret)
		goto err_put_module;

	/* check whether the driver indeed matched. I don't care if this
	 * is racy or not, because it can only happen on cardmgr access
	 * paths...
	 */
	if (!(p_dev->dev.driver == &p_drv->drv))
		p_dev->cardmgr = NULL;

 err_put_module:
	module_put(p_drv->owner);
 err_put_driver:
	put_driver(&p_drv->drv);
 err_put:
	pcmcia_put_socket(s);

	return (ret);
} /* bind_request */

#ifdef CONFIG_CARDBUS

static struct pci_bus *pcmcia_lookup_bus(struct pcmcia_socket *s)
{
	if (!s || !(s->state & SOCKET_CARDBUS))
		return NULL;

	return s->cb_dev->subordinate;
}
#endif

static int get_device_info(struct pcmcia_socket *s, bind_info_t *bind_info, int first)
{
	dev_node_t *node;
	struct pcmcia_device *p_dev;
	struct pcmcia_driver *p_drv;
	unsigned long flags;
	int ret = 0;

#ifdef CONFIG_CARDBUS
	/*
	 * Some unbelievably ugly code to associate the PCI cardbus
	 * device and its driver with the PCMCIA "bind" information.
	 */
	{
		struct pci_bus *bus;

		bus = pcmcia_lookup_bus(s);
		if (bus) {
			struct list_head *list;
			struct pci_dev *dev = NULL;

			list = bus->devices.next;
			while (list != &bus->devices) {
				struct pci_dev *pdev = pci_dev_b(list);
				list = list->next;

				if (first) {
					dev = pdev;
					break;
				}

				/* Try to handle "next" here some way? */
			}
			if (dev && dev->driver) {
				strlcpy(bind_info->name, dev->driver->name, DEV_NAME_LEN);
				bind_info->major = 0;
				bind_info->minor = 0;
				bind_info->next = NULL;
				return 0;
			}
		}
	}
#endif

	spin_lock_irqsave(&pcmcia_dev_list_lock, flags);
	list_for_each_entry(p_dev, &s->devices_list, socket_device_list) {
		if (p_dev->func == bind_info->function) {
			p_dev = pcmcia_get_dev(p_dev);
			if (!p_dev)
				continue;
			goto found;
		}
	}
	spin_unlock_irqrestore(&pcmcia_dev_list_lock, flags);
	return -ENODEV;

 found:
	spin_unlock_irqrestore(&pcmcia_dev_list_lock, flags);

	p_drv = to_pcmcia_drv(p_dev->dev.driver);
	if (p_drv && !p_dev->_locked) {
		ret = -EAGAIN;
		goto err_put;
	}

	if (first)
		node = p_dev->dev_node;
	else
		for (node = p_dev->dev_node; node; node = node->next)
			if (node == bind_info->next)
				break;
	if (!node) {
		ret = -ENODEV;
		goto err_put;
	}

	strlcpy(bind_info->name, node->dev_name, DEV_NAME_LEN);
	bind_info->major = node->major;
	bind_info->minor = node->minor;
	bind_info->next = node->next;

 err_put:
	pcmcia_put_dev(p_dev);
	return (ret);
} /* get_device_info */


static int ds_open(struct inode *inode, struct file *file)
{
    socket_t i = iminor(inode);
    struct pcmcia_socket *s;
    user_info_t *user;
    static int warning_printed = 0;

    ds_dbg(0, "ds_open(socket %d)\n", i);

    s = pcmcia_get_socket_by_nr(i);
    if (!s)