/*
 *  Copyright (C) 1997-1998     Mark Lord
 *  Copyright (C) 2003          Red Hat
 *
 *  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
 */

#include <linux/module.h>

#include <linux/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/ide.h>
#include <linux/seq_file.h>
#include <linux/slab.h>

#include <asm/io.h>

static struct proc_dir_entry *proc_ide_root;

static int ide_imodel_proc_show(struct seq_file *m, void *v)
{
        ide_hwif_t      *hwif = (ide_hwif_t *) m->private;
        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_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;
        }
        seq_printf(m, "%s\n", name);
        return 0;
}

static int ide_imodel_proc_open(struct inode *inode, struct file *file)
{
        return single_open(file, ide_imodel_proc_show, PDE_DATA(inode));
}

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

static int ide_mate_proc_show(struct seq_file *m, void *v)
{
        ide_hwif_t      *hwif = (ide_hwif_t *) m->private;

        if (hwif && hwif->mate)
                seq_printf(m, "%s\n", hwif->mate->name);
        else
                seq_printf(m, "(none)\n");
        return 0;
}

static int ide_mate_proc_open(struct inode *inode, struct file *file)
{
        return single_open(file, ide_mate_proc_show, PDE_DATA(inode));
}

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

static int ide_channel_proc_show(struct seq_file *m, void *v)
{
        ide_hwif_t      *hwif = (ide_hwif_t *) m->private;

        seq_printf(m, "%c\n", hwif->channel ? '1' : '0');
        return 0;
}

static int ide_channel_proc_open(struct inode *inode, struct file *file)
{
        return single_open(file, ide_channel_proc_show, PDE_DATA(inode));
}

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

static int ide_identify_proc_show(struct seq_file *m, void *v)
{
        ide_drive_t *drive = (ide_drive_t *)m->private;
        u8 *buf;

        if (!drive) {
                seq_putc(m, '\n');
                return 0;
        }

        buf = kmalloc(SECTOR_SIZE, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;
        if (taskfile_lib_get_identify(drive, buf) == 0) {
                __le16 *val = (__le16 *)buf;
                int i;

                for (i = 0; i < SECTOR_SIZE / 2; i++) {
                        seq_printf(m, "%04x%c", le16_to_cpu(val[i]),
                                        (i % 8) == 7 ? '\n' : ' ');
                }
        } else
                seq_putc(m, buf[0]);
        kfree(buf);
        return 0;
}

static int ide_identify_proc_open(struct inode *inode, struct file *file)
{
        return single_open(file, ide_identify_proc_show, PDE_DATA(inode));
}

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

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

static
const struct ide_proc_devset *ide_find_setting(const struct ide_proc_devset *st,
                                               char *name)
{
        while (st->name) {
                if (strcmp(st->name, name) == 0)
                        break;
                st++;
        }
        return st->name ? st : NULL;
}

/**
 *      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,
                            const struct ide_proc_devset *setting)
{
        const struct ide_devset *ds = setting->setting;
        int val = -EINVAL;

        if (ds->get)
                val = ds->get(drive);

        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,
                             const struct ide_proc_devset *setting, int val)
{
        const struct ide_devset *ds = setting->setting;

        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;
        if (!ds->set)
                return -EPERM;
        if ((ds->flags & DS_SYNC)
            && (val < setting->min || val > setting->max))
                return -EINVAL;
        return ide_devset_execute(drive, ds, val);
}

ide_devset_get(xfer_rate, current_speed);

static int set_xfer_rate (ide_drive_t *drive, int arg)
{
        struct ide_cmd cmd;

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

        memset(&cmd, 0, sizeof(cmd));
        cmd.tf.command = ATA_CMD_SET_FEATURES;
        cmd.tf.feature = SETFEATURES_XFER;
        cmd.tf.nsect   = (u8)arg;
        cmd.valid.out.tf = IDE_VALID_FEATURE | IDE_VALID_NSECT;
        cmd.valid.in.tf  = IDE_VALID_NSECT;
        cmd.tf_flags   = IDE_TFLAG_SET_XFER;

        return ide_no_data_taskfile(drive, &cmd);
}

ide_devset_rw(current_speed, xfer_rate);
ide_devset_rw_field(init_speed, init_speed);
ide_devset_rw_flag(nice1, IDE_DFLAG_NICE1);
ide_devset_rw_field(number, dn);

static const struct ide_proc_devset ide_generic_settings[] = {
        IDE_PROC_DEVSET(current_speed, 0, 70),
        IDE_PROC_DEVSET(init_speed, 0, 70),
        IDE_PROC_DEVSET(io_32bit,  0, 1 + (SUPPORT_VLB_SYNC << 1)),
        IDE_PROC_DEVSET(keepsettings, 0, 1),
        IDE_PROC_DEVSET(nice1, 0, 1),
        IDE_PROC_DEVSET(number, 0, 3),
        IDE_PROC_DEVSET(pio_mode, 0, 255),
        IDE_PROC_DEVSET(unmaskirq, 0, 1),
        IDE_PROC_DEVSET(using_dma, 0, 1),
        { NULL },
};

static void proc_ide_settings_warn(void)
{
        printk_once(KERN_WARNING "Warning: /proc/ide/hd?/settings interface is "
                            "obsolete, and will be removed soon!\n");
}

static int ide_settings_proc_show(struct seq_file *m, void *v)
{
        const struct ide_proc_devset *setting, *g, *d;
        const struct ide_devset *ds;
        ide_drive_t     *drive = (ide_drive_t *) m->private;
        int             rc, mul_factor, div_factor;

        proc_ide_settings_warn();

        mutex_lock(&ide_setting_mtx);
        g = ide_generic_settings;
        d = drive->settings;
        seq_printf(m, "name\t\t\tvalue\t\tmin\t\tmax\t\tmode\n");
        seq_printf(m, "----\t\t\t-----\t\t---\t\t---\t\t----\n");
        while (g->name || (d && d->name)) {
                /* read settings in the alphabetical order */
                if (g->name && d && d->name) {
                        if (strcmp(d->name, g->name) < 0)
                                setting = d++;
                        else
                                setting = g++;
                } else if (d && d->name) {
                        setting = d++;
                } else
                        setting = g++;
                mul_factor = setting->mulf ? setting->mulf(drive) : 1;
                div_factor = setting->divf ? setting->divf(drive) : 1;
                seq_printf(m, "%-24s", setting->name);
                rc = ide_read_setting(drive, setting);
                if (rc >= 0)
                        seq_printf(m, "%-16d", rc * mul_factor / div_factor);
                else
                        seq_printf(m, "%-16s", "write-only");
                seq_printf(m, "%-16d%-16d", (setting->min * mul_factor + div_factor - 1) / div_factor, setting->max * mul_factor / div_factor);
                ds = setting->setting;
                if (ds->get)
                        seq_printf(m, "r");
                if (ds->set)
                        seq_printf(m, "w");
                seq_printf(m, "\n");
        }
        mutex_unlock(&ide_setting_mtx);
        return 0;
}

static int ide_settings_proc_open(struct inode *inode, struct file *file)
{
        return single_open(file, ide_settings_proc_show, PDE_DATA(inode));
}

#define MAX_LEN 30

static ssize_t ide_settings_proc_write(struct file *file, const char __user *buffer,
                                       size_t count, loff_t *pos)
{
        ide_drive_t     *drive = PDE_DATA(file_inode(file));
        char            name[MAX_LEN + 1];
        int             for_real = 0, mul_factor, div_factor;
        unsigned long   n;

        const struct ide_proc_devset *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);
                        /* generic settings first, then driver specific ones */
                        setting = ide_find_setting(ide_generic_settings, name);
                        if (!setting) {
                                if (drive->settings)
                                        setting = ide_find_setting(drive->settings, name);
                                if (!setting) {
                                        mutex_unlock(&ide_setting_mtx);
                                        goto parse_error;
                                }
                        }
                        if (for_real) {
                                mul_factor = setting->mulf ? setting->mulf(drive) : 1;
                                div_factor = setting->divf ? setting->divf(drive) : 1;
                                ide_write_setting(drive, setting, val * div_factor / 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("%s(): parse error\n", __func__);
        return -EINVAL;
}

static const struct file_operations ide_settings_proc_fops = {
        .owner          = THIS_MODULE,
        .open           = ide_settings_proc_open,
        .read           = seq_read,
        .llseek         = seq_lseek,
        .release        = single_release,
        .write          = ide_settings_proc_write,
};

static int ide_capacity_proc_show(struct seq_file *m, void *v)
{
        seq_printf(m, "%llu\n", (long long)0x7fffffff);
        return 0;
}

static int ide_capacity_proc_open(struct inode *inode, struct file *file)
{
        return single_open(file, ide_capacity_proc_show, NULL);
}

const struct file_operations ide_capacity_proc_fops = {
        .owner          = THIS_MODULE,
        .open           = ide_capacity_proc_open,
        .read           = seq_read,
        .llseek         = seq_lseek,
        .release        = single_release,
};
EXPORT_SYMBOL_GPL(ide_capacity_proc_fops);

static int ide_geometry_proc_show(struct seq_file *m, void *v)
{
        ide_drive_t     *drive = (ide_drive_t *) m->private;

        seq_printf(m, "physical     %d/%d/%d\n",
                        drive->cyl, drive->head, drive->sect);
        seq_printf(m, "logical      %d/%d/%d\n",
                        drive->bios_cyl, drive->bios_head, drive->bios_sect);
        return 0;
}

static int ide_geometry_proc_open(struct inode *inode, struct file *file)
{
        return single_open(file, ide_geometry_proc_show, PDE_DATA(inode));
}

const struct file_operations ide_geometry_proc_fops = {
        .owner          = THIS_MODULE,
        .open           = ide_geometry_proc_open,
        .read           = seq_read,
        .llseek         = seq_lseek,
        .release        = single_release,
};
EXPORT_SYMBOL(ide_geometry_proc_fops);

static int ide_dmodel_proc_show(struct seq_file *seq, void *v)
{
        ide_drive_t     *drive = (ide_drive_t *) seq->private;
        char            *m = (char *)&drive->id[ATA_ID_PROD];

        seq_printf(seq, "%.40s\n", m[0] ? m : "(none)");
        return 0;
}

static int ide_dmodel_proc_open(struct inode *inode, struct file *file)
{
        return single_open(file, ide_dmodel_proc_show, PDE_DATA(inode));
}

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

static int ide_driver_proc_show(struct seq_file *m, void *v)
{
        ide_drive_t             *drive = (ide_drive_t *)m->private;
        struct device           *dev = &drive->gendev;
        struct ide_driver       *ide_drv;

        if (dev->driver) {
                ide_drv = to_ide_driver(dev->driver);
                seq_printf(m, "%s version %s\n",
                                dev->driver->name, ide_drv->version);
        } else
                seq_printf(m, "ide-default version 0.9.newide\n");
        return 0;
}

static int ide_driver_proc_open(struct inode *inode, struct file *file)
{
        return single_open(file, ide_driver_proc_show, PDE_DATA(inode));
}

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 ssize_t ide_driver_proc_write(struct file *file, const char __user *buffer,
                                     size_t count, loff_t *pos)
{
        ide_drive_t     *drive = PDE_DATA(file_inode(file));
        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 const struct file_operations ide_driver_proc_fops = {
        .owner          = THIS_MODULE,
        .open           = ide_driver_proc_open,
        .read           = seq_read,
        .llseek         = seq_lseek,
        .release        = single_release,
        .write          = ide_driver_proc_write,
};

static int ide_media_proc_show(struct seq_file *m, void *v)
{
        ide_drive_t     *drive = (ide_drive_t *) m->private;
        const char      *media;

        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;
        }
        seq_puts(m, media);
        return 0;
}

static int ide_media_proc_open(struct inode *inode, struct file *file)
{
        return single_open(file, ide_media_proc_show, PDE_DATA(inode));
}

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

static ide_proc_entry_t generic_drive_entries[] = {
        { "driver",     S_IFREG|S_IRUGO,         &ide_driver_proc_fops  },
        { "identify",   S_IFREG|S_IRUSR,         &ide_identify_proc_fops},
        { "media",      S_IFREG|S_IRUGO,         &ide_media_proc_fops   },
        { "model",      S_IFREG|S_IRUGO,         &ide_dmodel_proc_fops  },
        { "settings",   S_IFREG|S_IRUSR|S_IWUSR, &ide_settings_proc_fops},
        {}
};

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 = proc_create_data(p->name, p->mode, dir, p->proc_fops, data);
                if (!ent) return;
                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, struct ide_driver *driver)
{
        mutex_lock(&ide_setting_mtx);
        drive->settings = driver->proc_devsets(drive);
        mutex_unlock(&ide_setting_mtx);

        ide_add_proc_entries(drive->proc, driver->proc_entries(drive), 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.
 */

void ide_proc_unregister_driver(ide_drive_t *drive, struct ide_driver *driver)
{
        ide_remove_proc_entries(drive->proc, driver->proc_entries(drive));

        mutex_lock(&ide_setting_mtx);
        /*
         * ide_setting_mtx protects both the settings list and the use
         * of settings (we cannot take a setting out that is being used).
         */
        drive->settings = NULL;
        mutex_unlock(&ide_setting_mtx);
}
EXPORT_SYMBOL(ide_proc_unregister_driver);

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

        ide_port_for_each_dev(i, drive, hwif) {
                if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0)
                        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,        &ide_channel_proc_fops  },
        { "mate",       S_IFREG|S_IRUGO,        &ide_mate_proc_fops     },
        { "model",      S_IFREG|S_IRUGO,        &ide_imodel_proc_fops   },
        {}
};

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)
{
        struct ide_driver *ide_drv = to_ide_driver(drv);
        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);
}