ide-eh.c

Go to the documentation of this file.

#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/ide.h>
#include <linux/delay.h>

static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq,
                     u8 stat, u8 err)
{
    ide_hwif_t *hwif = drive->hwif;

    if ((stat & ATA_BUSY) ||
        ((stat & ATA_DF) && (drive->dev_flags & IDE_DFLAG_NOWERR) == 0)) {
        /* other bits are useless when BUSY */
        rq->errors |= ERROR_RESET;
    } else if (stat & ATA_ERR) {
        /* err has different meaning on cdrom and tape */
        if (err == ATA_ABORTED) {
            if ((drive->dev_flags & IDE_DFLAG_LBA) &&
                /* some newer drives don't support ATA_CMD_INIT_DEV_PARAMS */
                hwif->tp_ops->read_status(hwif) == ATA_CMD_INIT_DEV_PARAMS)
                return ide_stopped;
        } else if ((err & BAD_CRC) == BAD_CRC) {
            /* UDMA crc error, just retry the operation */
            drive->crc_count++;
        } else if (err & (ATA_BBK | ATA_UNC)) {
            /* retries won't help these */
            rq->errors = ERROR_MAX;
        } else if (err & ATA_TRK0NF) {
            /* help it find track zero */
            rq->errors |= ERROR_RECAL;
        }
    }

    if ((stat & ATA_DRQ) && rq_data_dir(rq) == READ &&
        (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0) {
        int nsect = drive->mult_count ? drive->mult_count : 1;

        ide_pad_transfer(drive, READ, nsect * SECTOR_SIZE);
    }

    if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) {
        ide_kill_rq(drive, rq);
        return ide_stopped;
    }

    if (hwif->tp_ops->read_status(hwif) & (ATA_BUSY | ATA_DRQ))
        rq->errors |= ERROR_RESET;

    if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
        ++rq->errors;
        return ide_do_reset(drive);
    }

    if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
        drive->special_flags |= IDE_SFLAG_RECALIBRATE;

    ++rq->errors;

    return ide_stopped;
}

static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq,
                       u8 stat, u8 err)
{
    ide_hwif_t *hwif = drive->hwif;

    if ((stat & ATA_BUSY) ||
        ((stat & ATA_DF) && (drive->dev_flags & IDE_DFLAG_NOWERR) == 0)) {
        /* other bits are useless when BUSY */
        rq->errors |= ERROR_RESET;
    } else {
        /* add decoding error stuff */
    }

    if (hwif->tp_ops->read_status(hwif) & (ATA_BUSY | ATA_DRQ))
        /* force an abort */
        hwif->tp_ops->exec_command(hwif, ATA_CMD_IDLEIMMEDIATE);

    if (rq->errors >= ERROR_MAX) {
        ide_kill_rq(drive, rq);
    } else {
        if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
            ++rq->errors;
            return ide_do_reset(drive);
        }
        ++rq->errors;
    }

    return ide_stopped;
}

static ide_startstop_t __ide_error(ide_drive_t *drive, struct request *rq,
                   u8 stat, u8 err)
{
    if (drive->media == ide_disk)
        return ide_ata_error(drive, rq, stat, err);
    return ide_atapi_error(drive, rq, stat, err);
}

ide_startstop_t ide_error(ide_drive_t *drive, const char *msg, u8 stat)
{
    struct request *rq;
    u8 err;

    err = ide_dump_status(drive, msg, stat);

    rq = drive->hwif->rq;
    if (rq == NULL)
        return ide_stopped;

    /* retry only "normal" I/O: */
    if (rq->cmd_type != REQ_TYPE_FS) {
        if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
            struct ide_cmd *cmd = rq->special;

            if (cmd)
                ide_complete_cmd(drive, cmd, stat, err);
        } else if (blk_pm_request(rq)) {
            rq->errors = 1;
            ide_complete_pm_rq(drive, rq);
            return ide_stopped;
        }
        rq->errors = err;
        ide_complete_rq(drive, err ? -EIO : 0, blk_rq_bytes(rq));
        return ide_stopped;
    }

    return __ide_error(drive, rq, stat, err);
}
EXPORT_SYMBOL_GPL(ide_error);

static inline void ide_complete_drive_reset(ide_drive_t *drive, int err)
{
    struct request *rq = drive->hwif->rq;

    if (rq && rq->cmd_type == REQ_TYPE_SPECIAL &&
        rq->cmd[0] == REQ_DRIVE_RESET) {
        if (err <= 0 && rq->errors == 0)
            rq->errors = -EIO;
        ide_complete_rq(drive, err ? err : 0, blk_rq_bytes(rq));
    }
}

/* needed below */
static ide_startstop_t do_reset1(ide_drive_t *, int);

/*
 * atapi_reset_pollfunc() gets invoked to poll the interface for completion
 * every 50ms during an atapi drive reset operation.  If the drive has not yet
 * responded, and we have not yet hit our maximum waiting time, then the timer
 * is restarted for another 50ms.
 */
static ide_startstop_t atapi_reset_pollfunc(ide_drive_t *drive)
{
    ide_hwif_t *hwif = drive->hwif;
    const struct ide_tp_ops *tp_ops = hwif->tp_ops;
    u8 stat;

    tp_ops->dev_select(drive);
    udelay(10);
    stat = tp_ops->read_status(hwif);

    if (OK_STAT(stat, 0, ATA_BUSY))
        printk(KERN_INFO "%s: ATAPI reset complete\n", drive->name);
    else {
        if (time_before(jiffies, hwif->poll_timeout)) {
            ide_set_handler(drive, &atapi_reset_pollfunc, HZ/20);
            /* continue polling */
            return ide_started;
        }
        /* end of polling */
        hwif->polling = 0;
        printk(KERN_ERR "%s: ATAPI reset timed-out, status=0x%02x\n",
            drive->name, stat);
        /* do it the old fashioned way */
        return do_reset1(drive, 1);
    }
    /* done polling */
    hwif->polling = 0;
    ide_complete_drive_reset(drive, 0);
    return ide_stopped;
}

static void ide_reset_report_error(ide_hwif_t *hwif, u8 err)
{
    static const char *err_master_vals[] =
        { NULL, "passed", "formatter device error",
          "sector buffer error", "ECC circuitry error",
          "controlling MPU error" };

    u8 err_master = err & 0x7f;

    printk(KERN_ERR "%s: reset: master: ", hwif->name);
    if (err_master && err_master < 6)
        printk(KERN_CONT "%s", err_master_vals[err_master]);
    else
        printk(KERN_CONT "error (0x%02x?)", err);
    if (err & 0x80)
        printk(KERN_CONT "; slave: failed");
    printk(KERN_CONT "\n");
}

/*
 * reset_pollfunc() gets invoked to poll the interface for completion every 50ms
 * during an ide reset operation. If the drives have not yet responded,
 * and we have not yet hit our maximum waiting time, then the timer is restarted
 * for another 50ms.
 */
static ide_startstop_t reset_pollfunc(ide_drive_t *drive)
{
    ide_hwif_t *hwif = drive->hwif;
    const struct ide_port_ops *port_ops = hwif->port_ops;
    u8 tmp;
    int err = 0;

    if (port_ops && port_ops->reset_poll) {
        err = port_ops->reset_poll(drive);
        if (err) {
            printk(KERN_ERR "%s: host reset_poll failure for %s.\n",
                hwif->name, drive->name);
            goto out;
        }
    }

    tmp = hwif->tp_ops->read_status(hwif);

    if (!OK_STAT(tmp, 0, ATA_BUSY)) {
        if (time_before(jiffies, hwif->poll_timeout)) {
            ide_set_handler(drive, &reset_pollfunc, HZ/20);
            /* continue polling */
            return ide_started;
        }
        printk(KERN_ERR "%s: reset timed-out, status=0x%02x\n",
            hwif->name, tmp);
        drive->failures++;
        err = -EIO;
    } else  {
        tmp = ide_read_error(drive);

        if (tmp == 1) {
            printk(KERN_INFO "%s: reset: success\n", hwif->name);
            drive->failures = 0;
        } else {
            ide_reset_report_error(hwif, tmp);
            drive->failures++;
            err = -EIO;
        }
    }
out:
    hwif->polling = 0;  /* done polling */
    ide_complete_drive_reset(drive, err);
    return ide_stopped;
}

static void ide_disk_pre_reset(ide_drive_t *drive)
{
    int legacy = (drive->id[ATA_ID_CFS_ENABLE_2] & 0x0400) ? 0 : 1;

    drive->special_flags =
        legacy ? (IDE_SFLAG_SET_GEOMETRY | IDE_SFLAG_RECALIBRATE) : 0;

    drive->mult_count = 0;
    drive->dev_flags &= ~IDE_DFLAG_PARKED;

    if ((drive->dev_flags & IDE_DFLAG_KEEP_SETTINGS) == 0 &&
        (drive->dev_flags & IDE_DFLAG_USING_DMA) == 0)
        drive->mult_req = 0;

    if (drive->mult_req != drive->mult_count)
        drive->special_flags |= IDE_SFLAG_SET_MULTMODE;
}

static void pre_reset(ide_drive_t *drive)
{
    const struct ide_port_ops *port_ops = drive->hwif->port_ops;

    if (drive->media == ide_disk)
        ide_disk_pre_reset(drive);
    else
        drive->dev_flags |= IDE_DFLAG_POST_RESET;

    if (drive->dev_flags & IDE_DFLAG_USING_DMA) {
        if (drive->crc_count)
            ide_check_dma_crc(drive);
        else
            ide_dma_off(drive);
    }

    if ((drive->dev_flags & IDE_DFLAG_KEEP_SETTINGS) == 0) {
        if ((drive->dev_flags & IDE_DFLAG_USING_DMA) == 0) {
            drive->dev_flags &= ~IDE_DFLAG_UNMASK;
            drive->io_32bit = 0;
        }
        return;
    }

    if (port_ops && port_ops->pre_reset)
        port_ops->pre_reset(drive);

    if (drive->current_speed != 0xff)
        drive->desired_speed = drive->current_speed;
    drive->current_speed = 0xff;
}

/*
 * do_reset1() attempts to recover a confused drive by resetting it.
 * Unfortunately, resetting a disk drive actually resets all devices on
 * the same interface, so it can really be thought of as resetting the
 * interface rather than resetting the drive.
 *
 * ATAPI devices have their own reset mechanism which allows them to be
 * individually reset without clobbering other devices on the same interface.
 *
 * Unfortunately, the IDE interface does not generate an interrupt to let
 * us know when the reset operation has finished, so we must poll for this.
 * Equally poor, though, is the fact that this may a very long time to complete,
 * (up to 30 seconds worstcase).  So, instead of busy-waiting here for it,
 * we set a timer to poll at 50ms intervals.
 */
static ide_startstop_t do_reset1(ide_drive_t *drive, int do_not_try_atapi)
{
    ide_hwif_t *hwif = drive->hwif;
    struct ide_io_ports *io_ports = &hwif->io_ports;
    const struct ide_tp_ops *tp_ops = hwif->tp_ops;
    const struct ide_port_ops *port_ops;
    ide_drive_t *tdrive;
    unsigned long flags, timeout;
    int i;
    DEFINE_WAIT(wait);

    spin_lock_irqsave(&hwif->lock, flags);

    /* We must not reset with running handlers */
    BUG_ON(hwif->handler != NULL);

    /* For an ATAPI device, first try an ATAPI SRST. */
    if (drive->media != ide_disk && !do_not_try_atapi) {
        pre_reset(drive);
        tp_ops->dev_select(drive);
        udelay(20);
        tp_ops->exec_command(hwif, ATA_CMD_DEV_RESET);
        ndelay(400);
        hwif->poll_timeout = jiffies + WAIT_WORSTCASE;
        hwif->polling = 1;
        __ide_set_handler(drive, &atapi_reset_pollfunc, HZ/20);
        spin_unlock_irqrestore(&hwif->lock, flags);
        return ide_started;
    }

    /* We must not disturb devices in the IDE_DFLAG_PARKED state. */
    do {
        unsigned long now;

        prepare_to_wait(&ide_park_wq, &wait, TASK_UNINTERRUPTIBLE);
        timeout = jiffies;
        ide_port_for_each_present_dev(i, tdrive, hwif) {
            if ((tdrive->dev_flags & IDE_DFLAG_PARKED) &&
                time_after(tdrive->sleep, timeout))
                timeout = tdrive->sleep;
        }

        now = jiffies;
        if (time_before_eq(timeout, now))
            break;

        spin_unlock_irqrestore(&hwif->lock, flags);
        timeout = schedule_timeout_uninterruptible(timeout - now);
        spin_lock_irqsave(&hwif->lock, flags);
    } while (timeout);
    finish_wait(&ide_park_wq, &wait);

    /*
     * First, reset any device state data we were maintaining
     * for any of the drives on this interface.
     */
    ide_port_for_each_dev(i, tdrive, hwif)
        pre_reset(tdrive);

    if (io_ports->ctl_addr == 0) {
        spin_unlock_irqrestore(&hwif->lock, flags);
        ide_complete_drive_reset(drive, -ENXIO);
        return ide_stopped;
    }

    /*
     * Note that we also set nIEN while resetting the device,
     * to mask unwanted interrupts from the interface during the reset.
     * However, due to the design of PC hardware, this will cause an
     * immediate interrupt due to the edge transition it produces.
     * This single interrupt gives us a "fast poll" for drives that
     * recover from reset very quickly, saving us the first 50ms wait time.
     */
    /* set SRST and nIEN */
    tp_ops->write_devctl(hwif, ATA_SRST | ATA_NIEN | ATA_DEVCTL_OBS);
    /* more than enough time */
    udelay(10);
    /* clear SRST, leave nIEN (unless device is on the quirk list) */
    tp_ops->write_devctl(hwif,
        ((drive->dev_flags & IDE_DFLAG_NIEN_QUIRK) ? 0 : ATA_NIEN) |
         ATA_DEVCTL_OBS);
    /* more than enough time */
    udelay(10);
    hwif->poll_timeout = jiffies + WAIT_WORSTCASE;
    hwif->polling = 1;
    __ide_set_handler(drive, &reset_pollfunc, HZ/20);

    /*
     * Some weird controller like resetting themselves to a strange
     * state when the disks are reset this way. At least, the Winbond
     * 553 documentation says that
     */
    port_ops = hwif->port_ops;
    if (port_ops && port_ops->resetproc)
        port_ops->resetproc(drive);

    spin_unlock_irqrestore(&hwif->lock, flags);
    return ide_started;
}

/*
 * ide_do_reset() is the entry point to the drive/interface reset code.
 */

ide_startstop_t ide_do_reset(ide_drive_t *drive)
{
    return do_reset1(drive, 0);
}
EXPORT_SYMBOL(ide_do_reset);