ACPICA: Additional error checking for pathname utilities

[linux-2.6/mini2440.git] / drivers / ide / ide-proc.c

/*
 *  Copyright (C) 1997-1998     Mark Lord
 *  Copyright (C) 2003          Red Hat <alan@redhat.com>
 *
 *  Some code was moved here from ide.c, see it for original copyrights.
 */

/*
 * This is the /proc/ide/ filesystem implementation.
 *
 * Drive/Driver settings can be retrieved by reading the drive's
 * "settings" files.  e.g.    "cat /proc/ide0/hda/settings"
 * To write a new value "val" into a specific setting "name", use:
 *   echo "name:val" >/proc/ide/ide0/hda/settings
 *
 * Also useful, "cat /proc/ide0/hda/[identify, smart_values,
 * smart_thresholds, capabilities]" will issue an IDENTIFY /
 * PACKET_IDENTIFY / SMART_READ_VALUES / SMART_READ_THRESHOLDS /
 * SENSE CAPABILITIES command to /dev/hda, and then dump out the
 * returned data as 256 16-bit words.  The "hdparm" utility will
 * be updated someday soon to use this mechanism.
 *
 */

#include <linux/module.h>

#include <asm/uaccess.h>
#include <linux/errno.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/mm.h>
#include <linux/pci.h>
#include <linux/ctype.h>
#include <linux/hdreg.h>
#include <linux/ide.h>
#include <linux/seq_file.h>

#include <asm/io.h>

static struct proc_dir_entry *proc_ide_root;

static int proc_ide_read_imodel
        (char *page, char **start, off_t off, int count, int *eof, void *data)
{
        ide_hwif_t      *hwif = (ide_hwif_t *) data;
        int             len;
        const char      *name;

        switch (hwif->chipset) {
        case ide_generic:       name = "generic";       break;
        case ide_pci:           name = "pci";           break;
        case ide_cmd640:        name = "cmd640";        break;
        case ide_dtc2278:       name = "dtc2278";       break;
        case ide_ali14xx:       name = "ali14xx";       break;
        case ide_qd65xx:        name = "qd65xx";        break;
        case ide_umc8672:       name = "umc8672";       break;
        case ide_ht6560b:       name = "ht6560b";       break;
        case ide_rz1000:        name = "rz1000";        break;
        case ide_trm290:        name = "trm290";        break;
        case ide_cmd646:        name = "cmd646";        break;
        case ide_cy82c693:      name = "cy82c693";      break;
        case ide_4drives:       name = "4drives";       break;
        case ide_pmac:          name = "mac-io";        break;
        case ide_au1xxx:        name = "au1xxx";        break;
        case ide_palm3710:      name = "palm3710";      break;
        case ide_acorn:         name = "acorn";         break;
        default:                name = "(unknown)";     break;
        }
        len = sprintf(page, "%s\n", name);
        PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
}

static int proc_ide_read_mate
        (char *page, char **start, off_t off, int count, int *eof, void *data)
{
        ide_hwif_t      *hwif = (ide_hwif_t *) data;
        int             len;

        if (hwif && hwif->mate)
                len = sprintf(page, "%s\n", hwif->mate->name);
        else
                len = sprintf(page, "(none)\n");
        PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
}

static int proc_ide_read_channel
        (char *page, char **start, off_t off, int count, int *eof, void *data)
{
        ide_hwif_t      *hwif = (ide_hwif_t *) data;
        int             len;

        page[0] = hwif->channel ? '1' : '0';
        page[1] = '\n';
        len = 2;
        PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
}

static int proc_ide_read_identify
        (char *page, char **start, off_t off, int count, int *eof, void *data)
{
        ide_drive_t     *drive = (ide_drive_t *)data;
        int             len = 0, i = 0;
        int             err = 0;

        len = sprintf(page, "\n");

        if (drive) {
                __le16 *val = (__le16 *)page;

                err = taskfile_lib_get_identify(drive, page);
                if (!err) {
                        char *out = ((char *)page) + (SECTOR_WORDS * 4);
                        page = out;
                        do {
                                out += sprintf(out, "%04x%c",
                                        le16_to_cpup(val), (++i & 7) ? ' ' : '\n');
                                val += 1;
                        } while (i < (SECTOR_WORDS * 2));
                        len = out - page;
                }
        }
        PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
}

/**
 *      __ide_add_setting       -       add an ide setting option
 *      @drive: drive to use
 *      @name: setting name
 *      @rw: true if the function is read write
 *      @data_type: type of data
 *      @min: range minimum
 *      @max: range maximum
 *      @mul_factor: multiplication scale
 *      @div_factor: divison scale
 *      @data: private data field
 *      @set: setting
 *      @auto_remove: setting auto removal flag
 *
 *      Removes the setting named from the device if it is present.
 *      The function takes the settings_lock to protect against
 *      parallel changes. This function must not be called from IRQ
 *      context. Returns 0 on success or -1 on failure.
 *
 *      BUGS: This code is seriously over-engineered. There is also
 *      magic about how the driver specific features are setup. If
 *      a driver is attached we assume the driver settings are auto
 *      remove.
 */

static int __ide_add_setting(ide_drive_t *drive, const char *name, int rw, int data_type, int min, int max, int mul_factor, int div_factor, void *data, ide_procset_t *set, int auto_remove)
{
        ide_settings_t **p = (ide_settings_t **) &drive->settings, *setting = NULL;

        mutex_lock(&ide_setting_mtx);
        while ((*p) && strcmp((*p)->name, name) < 0)
                p = &((*p)->next);
        if ((setting = kzalloc(sizeof(*setting), GFP_KERNEL)) == NULL)
                goto abort;
        if ((setting->name = kmalloc(strlen(name) + 1, GFP_KERNEL)) == NULL)
                goto abort;
        strcpy(setting->name, name);
        setting->rw = rw;
        setting->data_type = data_type;
        setting->min = min;
        setting->max = max;
        setting->mul_factor = mul_factor;
        setting->div_factor = div_factor;
        setting->data = data;
        setting->set = set;

        setting->next = *p;
        if (auto_remove)
                setting->auto_remove = 1;
        *p = setting;
        mutex_unlock(&ide_setting_mtx);
        return 0;
abort:
        mutex_unlock(&ide_setting_mtx);
        kfree(setting);
        return -1;
}

int ide_add_setting(ide_drive_t *drive, const char *name, int rw, int data_type, int min, int max, int mul_factor, int div_factor, void *data, ide_procset_t *set)
{
        return __ide_add_setting(drive, name, rw, data_type, min, max, mul_factor, div_factor, data, set, 1);
}

EXPORT_SYMBOL(ide_add_setting);

/**
 *      __ide_remove_setting    -       remove an ide setting option
 *      @drive: drive to use
 *      @name: setting name
 *
 *      Removes the setting named from the device if it is present.
 *      The caller must hold the setting semaphore.
 */

static void __ide_remove_setting(ide_drive_t *drive, char *name)
{
        ide_settings_t **p, *setting;

        p = (ide_settings_t **) &drive->settings;

        while ((*p) && strcmp((*p)->name, name))
                p = &((*p)->next);
        setting = (*p);
        if (setting == NULL)
                return;

        (*p) = setting->next;

        kfree(setting->name);
        kfree(setting);
}

/**
 *      auto_remove_settings    -       remove driver specific settings
 *      @drive: drive
 *
 *      Automatically remove all the driver specific settings for this
 *      drive. This function may not be called from IRQ context. The
 *      caller must hold ide_setting_mtx.
 */

static void auto_remove_settings(ide_drive_t *drive)
{
        ide_settings_t *setting;
repeat:
        setting = drive->settings;
        while (setting) {
                if (setting->auto_remove) {
                        __ide_remove_setting(drive, setting->name);
                        goto repeat;
                }
                setting = setting->next;
        }
}

/**
 *      ide_find_setting_by_name        -       find a drive specific setting
 *      @drive: drive to scan
 *      @name: setting name
 *
 *      Scan's the device setting table for a matching entry and returns
 *      this or NULL if no entry is found. The caller must hold the
 *      setting semaphore
 */

static ide_settings_t *ide_find_setting_by_name(ide_drive_t *drive, char *name)
{
        ide_settings_t *setting = drive->settings;

        while (setting) {
                if (strcmp(setting->name, name) == 0)
                        break;
                setting = setting->next;
        }
        return setting;
}

/**
 *      ide_read_setting        -       read an IDE setting
 *      @drive: drive to read from
 *      @setting: drive setting
 *
 *      Read a drive setting and return the value. The caller
 *      must hold the ide_setting_mtx when making this call.
 *
 *      BUGS: the data return and error are the same return value
 *      so an error -EINVAL and true return of the same value cannot
 *      be told apart
 */

static int ide_read_setting(ide_drive_t *drive, ide_settings_t *setting)
{
        int             val = -EINVAL;
        unsigned long   flags;

        if ((setting->rw & SETTING_READ)) {
                spin_lock_irqsave(&ide_lock, flags);
                switch (setting->data_type) {
                case TYPE_BYTE:
                        val = *((u8 *) setting->data);
                        break;
                case TYPE_SHORT:
                        val = *((u16 *) setting->data);
                        break;
                case TYPE_INT:
                        val = *((u32 *) setting->data);
                        break;
                }
                spin_unlock_irqrestore(&ide_lock, flags);
        }
        return val;
}

/**
 *      ide_write_setting       -       read an IDE setting
 *      @drive: drive to read from
 *      @setting: drive setting
 *      @val: value
 *
 *      Write a drive setting if it is possible. The caller
 *      must hold the ide_setting_mtx when making this call.
 *
 *      BUGS: the data return and error are the same return value
 *      so an error -EINVAL and true return of the same value cannot
 *      be told apart
 *
 *      FIXME:  This should be changed to enqueue a special request
 *      to the driver to change settings, and then wait on a sema for completion.
 *      The current scheme of polling is kludgy, though safe enough.
 */

static int ide_write_setting(ide_drive_t *drive, ide_settings_t *setting, int val)
{
        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;
        if (setting->set)
                return setting->set(drive, val);
        if (!(setting->rw & SETTING_WRITE))
                return -EPERM;
        if (val < setting->min || val > setting->max)
                return -EINVAL;
        if (ide_spin_wait_hwgroup(drive))
                return -EBUSY;
        switch (setting->data_type) {
        case TYPE_BYTE:
                *((u8 *) setting->data) = val;
                break;
        case TYPE_SHORT:
                *((u16 *) setting->data) = val;
                break;
        case TYPE_INT:
                *((u32 *) setting->data) = val;
                break;
        }
        spin_unlock_irq(&ide_lock);
        return 0;
}

static int set_xfer_rate (ide_drive_t *drive, int arg)
{
        ide_task_t task;
        int err;

        if (arg < XFER_PIO_0 || arg > XFER_UDMA_6)
                return -EINVAL;

        memset(&task, 0, sizeof(task));
        task.tf.command = WIN_SETFEATURES;
        task.tf.feature = SETFEATURES_XFER;
        task.tf.nsect   = (u8)arg;
        task.tf_flags = IDE_TFLAG_OUT_FEATURE | IDE_TFLAG_OUT_NSECT |
                        IDE_TFLAG_IN_NSECT;

        err = ide_no_data_taskfile(drive, &task);

        if (!err) {
                ide_set_xfer_rate(drive, (u8) arg);
                ide_driveid_update(drive);
        }
        return err;
}

/**
 *      ide_add_generic_settings        -       generic ide settings
 *      @drive: drive being configured
 *
 *      Add the generic parts of the system settings to the /proc files.
 *      The caller must not be holding the ide_setting_mtx.
 */

void ide_add_generic_settings (ide_drive_t *drive)
{
/*
 *                        drive         setting name            read/write access                               data type       min     max                             mul_factor      div_factor      data pointer                    set function
 */
        __ide_add_setting(drive,        "io_32bit",             drive->no_io_32bit ? SETTING_READ : SETTING_RW, TYPE_BYTE,      0,      1 + (SUPPORT_VLB_SYNC << 1),    1,              1,              &drive->io_32bit,               set_io_32bit,   0);
        __ide_add_setting(drive,        "keepsettings",         SETTING_RW,                                     TYPE_BYTE,      0,      1,                              1,              1,              &drive->keep_settings,          NULL,           0);
        __ide_add_setting(drive,        "nice1",                SETTING_RW,                                     TYPE_BYTE,      0,      1,                              1,              1,              &drive->nice1,                  NULL,           0);
        __ide_add_setting(drive,        "pio_mode",             SETTING_WRITE,                                  TYPE_BYTE,      0,      255,                            1,              1,              NULL,                           set_pio_mode,   0);
        __ide_add_setting(drive,        "unmaskirq",            drive->no_unmask ? SETTING_READ : SETTING_RW,   TYPE_BYTE,      0,      1,                              1,              1,              &drive->unmask,                 NULL,           0);
        __ide_add_setting(drive,        "using_dma",            SETTING_RW,                                     TYPE_BYTE,      0,      1,                              1,              1,              &drive->using_dma,              set_using_dma,  0);
        __ide_add_setting(drive,        "init_speed",           SETTING_RW,                                     TYPE_BYTE,      0,      70,                             1,              1,              &drive->init_speed,             NULL,           0);
        __ide_add_setting(drive,        "current_speed",        SETTING_RW,                                     TYPE_BYTE,      0,      70,                             1,              1,              &drive->current_speed,          set_xfer_rate,  0);
        __ide_add_setting(drive,        "number",               SETTING_RW,                                     TYPE_BYTE,      0,      3,                              1,              1,              &drive->dn,                     NULL,           0);
}

static void proc_ide_settings_warn(void)
{
        static int warned;

        if (warned)
                return;

        printk(KERN_WARNING "Warning: /proc/ide/hd?/settings interface is "
                            "obsolete, and will be removed soon!\n");
        warned = 1;
}

static int proc_ide_read_settings
        (char *page, char **start, off_t off, int count, int *eof, void *data)
{
        ide_drive_t     *drive = (ide_drive_t *) data;
        ide_settings_t  *setting = (ide_settings_t *) drive->settings;
        char            *out = page;
        int             len, rc, mul_factor, div_factor;

        proc_ide_settings_warn();

        mutex_lock(&ide_setting_mtx);
        out += sprintf(out, "name\t\t\tvalue\t\tmin\t\tmax\t\tmode\n");
        out += sprintf(out, "----\t\t\t-----\t\t---\t\t---\t\t----\n");
        while (setting) {
                mul_factor = setting->mul_factor;
                div_factor = setting->div_factor;
                out += sprintf(out, "%-24s", setting->name);
                rc = ide_read_setting(drive, setting);
                if (rc >= 0)
                        out += sprintf(out, "%-16d", rc * mul_factor / div_factor);
                else
                        out += sprintf(out, "%-16s", "write-only");
                out += sprintf(out, "%-16d%-16d", (setting->min * mul_factor + div_factor - 1) / div_factor, setting->max * mul_factor / div_factor);
                if (setting->rw & SETTING_READ)
                        out += sprintf(out, "r");
                if (setting->rw & SETTING_WRITE)
                        out += sprintf(out, "w");
                out += sprintf(out, "\n");
                setting = setting->next;
        }
        len = out - page;
        mutex_unlock(&ide_setting_mtx);
        PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
}

#define MAX_LEN 30

static int proc_ide_write_settings(struct file *file, const char __user *buffer,
                                   unsigned long count, void *data)
{
        ide_drive_t     *drive = (ide_drive_t *) data;
        char            name[MAX_LEN + 1];
        int             for_real = 0;
        unsigned long   n;
        ide_settings_t  *setting;
        char *buf, *s;

        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;

        proc_ide_settings_warn();

        if (count >= PAGE_SIZE)
                return -EINVAL;

        s = buf = (char *)__get_free_page(GFP_USER);
        if (!buf)
                return -ENOMEM;

        if (copy_from_user(buf, buffer, count)) {
                free_page((unsigned long)buf);
                return -EFAULT;
        }

        buf[count] = '\0';

        /*
         * Skip over leading whitespace
         */
        while (count && isspace(*s)) {
                --count;
                ++s;
        }
        /*
         * Do one full pass to verify all parameters,
         * then do another to actually write the new settings.
         */
        do {
                char *p = s;
                n = count;
                while (n > 0) {
                        unsigned val;
                        char *q = p;

                        while (n > 0 && *p != ':') {
                                --n;
                                p++;
                        }
                        if (*p != ':')
                                goto parse_error;
                        if (p - q > MAX_LEN)
                                goto parse_error;
                        memcpy(name, q, p - q);
                        name[p - q] = 0;

                        if (n > 0) {
                                --n;
                                p++;
                        } else
                                goto parse_error;

                        val = simple_strtoul(p, &q, 10);
                        n -= q - p;
                        p = q;
                        if (n > 0 && !isspace(*p))
                                goto parse_error;
                        while (n > 0 && isspace(*p)) {
                                --n;
                                ++p;
                        }

                        mutex_lock(&ide_setting_mtx);
                        setting = ide_find_setting_by_name(drive, name);
                        if (!setting) {
                                mutex_unlock(&ide_setting_mtx);
                                goto parse_error;
                        }
                        if (for_real)
                                ide_write_setting(drive, setting, val * setting->div_factor / setting->mul_factor);
                        mutex_unlock(&ide_setting_mtx);
                }
        } while (!for_real++);
        free_page((unsigned long)buf);
        return count;
parse_error:
        free_page((unsigned long)buf);
        printk("proc_ide_write_settings(): parse error\n");
        return -EINVAL;
}

int proc_ide_read_capacity
        (char *page, char **start, off_t off, int count, int *eof, void *data)
{
        int len = sprintf(page, "%llu\n", (long long)0x7fffffff);
        PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
}

EXPORT_SYMBOL_GPL(proc_ide_read_capacity);

int proc_ide_read_geometry
        (char *page, char **start, off_t off, int count, int *eof, void *data)
{
        ide_drive_t     *drive = (ide_drive_t *) data;
        char            *out = page;
        int             len;

        out += sprintf(out, "physical     %d/%d/%d\n",
                        drive->cyl, drive->head, drive->sect);
        out += sprintf(out, "logical      %d/%d/%d\n",
                        drive->bios_cyl, drive->bios_head, drive->bios_sect);

        len = out - page;
        PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
}

EXPORT_SYMBOL(proc_ide_read_geometry);

static int proc_ide_read_dmodel
        (char *page, char **start, off_t off, int count, int *eof, void *data)
{
        ide_drive_t     *drive = (ide_drive_t *) data;
        struct hd_driveid *id = drive->id;
        int             len;

        len = sprintf(page, "%.40s\n",
                (id && id->model[0]) ? (char *)id->model : "(none)");
        PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
}

static int proc_ide_read_driver
        (char *page, char **start, off_t off, int count, int *eof, void *data)
{
        ide_drive_t     *drive = (ide_drive_t *) data;
        struct device   *dev = &drive->gendev;
        ide_driver_t    *ide_drv;
        int             len;

        if (dev->driver) {
                ide_drv = container_of(dev->driver, ide_driver_t, gen_driver);
                len = sprintf(page, "%s version %s\n",
                                dev->driver->name, ide_drv->version);
        } else
                len = sprintf(page, "ide-default version 0.9.newide\n");
        PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
}

static int ide_replace_subdriver(ide_drive_t *drive, const char *driver)
{
        struct device *dev = &drive->gendev;
        int ret = 1;
        int err;

        device_release_driver(dev);
        /* FIXME: device can still be in use by previous driver */
        strlcpy(drive->driver_req, driver, sizeof(drive->driver_req));
        err = device_attach(dev);
        if (err < 0)
                printk(KERN_WARNING "IDE: %s: device_attach error: %d\n",
                        __func__, err);
        drive->driver_req[0] = 0;
        if (dev->driver == NULL) {
                err = device_attach(dev);
                if (err < 0)
                        printk(KERN_WARNING
                                "IDE: %s: device_attach(2) error: %d\n",
                                __func__, err);
        }
        if (dev->driver && !strcmp(dev->driver->name, driver))
                ret = 0;

        return ret;
}

static int proc_ide_write_driver
        (struct file *file, const char __user *buffer, unsigned long count, void *data)
{
        ide_drive_t     *drive = (ide_drive_t *) data;
        char name[32];

        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;
        if (count > 31)
                count = 31;
        if (copy_from_user(name, buffer, count))
                return -EFAULT;
        name[count] = '\0';
        if (ide_replace_subdriver(drive, name))
                return -EINVAL;
        return count;
}

static int proc_ide_read_media
        (char *page, char **start, off_t off, int count, int *eof, void *data)
{
        ide_drive_t     *drive = (ide_drive_t *) data;
        const char      *media;
        int             len;

        switch (drive->media) {
        case ide_disk:          media = "disk\n";       break;
        case ide_cdrom:         media = "cdrom\n";      break;
        case ide_tape:          media = "tape\n";       break;
        case ide_floppy:        media = "floppy\n";     break;
        case ide_optical:       media = "optical\n";    break;
        default:                media = "UNKNOWN\n";    break;
        }
        strcpy(page, media);
        len = strlen(media);
        PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
}

static ide_proc_entry_t generic_drive_entries[] = {
        { "driver",     S_IFREG|S_IRUGO,         proc_ide_read_driver,
                                                 proc_ide_write_driver },
        { "identify",   S_IFREG|S_IRUSR,         proc_ide_read_identify, NULL },
        { "media",      S_IFREG|S_IRUGO,         proc_ide_read_media,    NULL },
        { "model",      S_IFREG|S_IRUGO,         proc_ide_read_dmodel,   NULL },
        { "settings",   S_IFREG|S_IRUSR|S_IWUSR, proc_ide_read_settings,
                                                 proc_ide_write_settings },
        { NULL, 0, NULL, NULL }
};

static void ide_add_proc_entries(struct proc_dir_entry *dir, ide_proc_entry_t *p, void *data)
{
        struct proc_dir_entry *ent;

        if (!dir || !p)
                return;
        while (p->name != NULL) {
                ent = create_proc_entry(p->name, p->mode, dir);
                if (!ent) return;
                ent->data = data;
                ent->read_proc = p->read_proc;
                ent->write_proc = p->write_proc;
                p++;
        }
}

static void ide_remove_proc_entries(struct proc_dir_entry *dir, ide_proc_entry_t *p)
{
        if (!dir || !p)
                return;
        while (p->name != NULL) {
                remove_proc_entry(p->name, dir);
                p++;
        }
}

void ide_proc_register_driver(ide_drive_t *drive, ide_driver_t *driver)
{
        ide_add_proc_entries(drive->proc, driver->proc, drive);
}

EXPORT_SYMBOL(ide_proc_register_driver);

/**
 *      ide_proc_unregister_driver      -       remove driver specific data
 *      @drive: drive
 *      @driver: driver
 *
 *      Clean up the driver specific /proc files and IDE settings
 *      for a given drive.
 *
 *      Takes ide_setting_mtx and ide_lock.
 *      Caller must hold none of the locks.
 */

void ide_proc_unregister_driver(ide_drive_t *drive, ide_driver_t *driver)
{
        unsigned long flags;

        ide_remove_proc_entries(drive->proc, driver->proc);

        mutex_lock(&ide_setting_mtx);
        spin_lock_irqsave(&ide_lock, flags);
        /*
         * ide_setting_mtx protects the settings list
         * ide_lock protects the use of settings
         *
         * so we need to hold both, ide_settings_sem because we want to
         * modify the settings list, and ide_lock because we cannot take
         * a setting out that is being used.
         *
         * OTOH both ide_{read,write}_setting are only ever used under
         * ide_setting_mtx.
         */
        auto_remove_settings(drive);
        spin_unlock_irqrestore(&ide_lock, flags);
        mutex_unlock(&ide_setting_mtx);
}
EXPORT_SYMBOL(ide_proc_unregister_driver);

void ide_proc_port_register_devices(ide_hwif_t *hwif)
{
        int     d;
        struct proc_dir_entry *ent;
        struct proc_dir_entry *parent = hwif->proc;
        char name[64];

        for (d = 0; d < MAX_DRIVES; d++) {
                ide_drive_t *drive = &hwif->drives[d];

                if (!drive->present)
                        continue;
                if (drive->proc)
                        continue;

                drive->proc = proc_mkdir(drive->name, parent);
                if (drive->proc)
                        ide_add_proc_entries(drive->proc, generic_drive_entries, drive);
                sprintf(name, "ide%d/%s", (drive->name[2]-'a')/2, drive->name);
                ent = proc_symlink(drive->name, proc_ide_root, name);
                if (!ent) return;
        }
}

void ide_proc_unregister_device(ide_drive_t *drive)
{
        if (drive->proc) {
                ide_remove_proc_entries(drive->proc, generic_drive_entries);
                remove_proc_entry(drive->name, proc_ide_root);
                remove_proc_entry(drive->name, drive->hwif->proc);
                drive->proc = NULL;
        }
}

static ide_proc_entry_t hwif_entries[] = {
        { "channel",    S_IFREG|S_IRUGO,        proc_ide_read_channel,  NULL },
        { "mate",       S_IFREG|S_IRUGO,        proc_ide_read_mate,     NULL },
        { "model",      S_IFREG|S_IRUGO,        proc_ide_read_imodel,   NULL },
        { NULL, 0, NULL, NULL }
};

void ide_proc_register_port(ide_hwif_t *hwif)
{
        if (!hwif->proc) {
                hwif->proc = proc_mkdir(hwif->name, proc_ide_root);

                if (!hwif->proc)
                        return;

                ide_add_proc_entries(hwif->proc, hwif_entries, hwif);
        }
}

void ide_proc_unregister_port(ide_hwif_t *hwif)
{
        if (hwif->proc) {
                ide_remove_proc_entries(hwif->proc, hwif_entries);
                remove_proc_entry(hwif->name, proc_ide_root);
                hwif->proc = NULL;
        }
}

static int proc_print_driver(struct device_driver *drv, void *data)
{
        ide_driver_t *ide_drv = container_of(drv, ide_driver_t, gen_driver);
        struct seq_file *s = data;

        seq_printf(s, "%s version %s\n", drv->name, ide_drv->version);

        return 0;
}

static int ide_drivers_show(struct seq_file *s, void *p)
{
        int err;

        err = bus_for_each_drv(&ide_bus_type, NULL, s, proc_print_driver);
        if (err < 0)
                printk(KERN_WARNING "IDE: %s: bus_for_each_drv error: %d\n",
                        __func__, err);
        return 0;
}

static int ide_drivers_open(struct inode *inode, struct file *file)
{
        return single_open(file, &ide_drivers_show, NULL);
}

static const struct file_operations ide_drivers_operations = {
        .owner          = THIS_MODULE,
        .open           = ide_drivers_open,
        .read           = seq_read,
        .llseek         = seq_lseek,
        .release        = single_release,
};

void proc_ide_create(void)
{
        proc_ide_root = proc_mkdir("ide", NULL);

        if (!proc_ide_root)
                return;

        proc_create("drivers", 0, proc_ide_root, &ide_drivers_operations);
}

void proc_ide_destroy(void)
{
        remove_proc_entry("drivers", proc_ide_root);
        remove_proc_entry("ide", NULL);
}