LXR linux/drivers/ide/ide-park.c

   1#include <linux/kernel.h>
   2#include <linux/gfp.h>
   3#include <linux/ide.h>
   4#include <linux/jiffies.h>
   5#include <linux/blkdev.h>
   6
   7DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
   8
   9static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout)
  10{
  11        ide_hwif_t *hwif = drive->hwif;
  12        struct request_queue *q = drive->queue;
  13        struct request *rq;
  14        int rc;
  15
  16        timeout += jiffies;
  17        spin_lock_irq(&hwif->lock);
  18        if (drive->dev_flags & IDE_DFLAG_PARKED) {
  19                int reset_timer = time_before(timeout, drive->sleep);
  20                int start_queue = 0;
  21
  22                drive->sleep = timeout;
  23                wake_up_all(&ide_park_wq);
  24                if (reset_timer && del_timer(&hwif->timer))
  25                        start_queue = 1;
  26                spin_unlock_irq(&hwif->lock);
  27
  28                if (start_queue)
  29                        blk_run_queue(q);
  30                return;
  31        }
  32        spin_unlock_irq(&hwif->lock);
  33
  34        rq = blk_get_request(q, REQ_OP_DRV_IN, __GFP_RECLAIM);
  35        scsi_req_init(rq);
  36        scsi_req(rq)->cmd[0] = REQ_PARK_HEADS;
  37        scsi_req(rq)->cmd_len = 1;
  38        ide_req(rq)->type = ATA_PRIV_MISC;
  39        rq->special = &timeout;
  40        blk_execute_rq(q, NULL, rq, 1);
  41        rc = scsi_req(rq)->result ? -EIO : 0;
  42        blk_put_request(rq);
  43        if (rc)
  44                goto out;
  45
  46        /*
  47         * Make sure that *some* command is sent to the drive after the
  48         * timeout has expired, so power management will be reenabled.
  49         */
  50        rq = blk_get_request(q, REQ_OP_DRV_IN, GFP_NOWAIT);
  51        scsi_req_init(rq);
  52        if (IS_ERR(rq))
  53                goto out;
  54
  55        scsi_req(rq)->cmd[0] = REQ_UNPARK_HEADS;
  56        scsi_req(rq)->cmd_len = 1;
  57        ide_req(rq)->type = ATA_PRIV_MISC;
  58        elv_add_request(q, rq, ELEVATOR_INSERT_FRONT);
  59
  60out:
  61        return;
  62}
  63
  64ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
  65{
  66        struct ide_cmd cmd;
  67        struct ide_taskfile *tf = &cmd.tf;
  68
  69        memset(&cmd, 0, sizeof(cmd));
  70        if (scsi_req(rq)->cmd[0] == REQ_PARK_HEADS) {
  71                drive->sleep = *(unsigned long *)rq->special;
  72                drive->dev_flags |= IDE_DFLAG_SLEEPING;
  73                tf->command = ATA_CMD_IDLEIMMEDIATE;
  74                tf->feature = 0x44;
  75                tf->lbal = 0x4c;
  76                tf->lbam = 0x4e;
  77                tf->lbah = 0x55;
  78                cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
  79                cmd.valid.in.tf  = IDE_VALID_IN_TF  | IDE_VALID_DEVICE;
  80        } else          /* cmd == REQ_UNPARK_HEADS */
  81                tf->command = ATA_CMD_CHK_POWER;
  82
  83        cmd.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
  84        cmd.protocol = ATA_PROT_NODATA;
  85
  86        cmd.rq = rq;
  87
  88        return do_rw_taskfile(drive, &cmd);
  89}
  90
  91ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,
  92                      char *buf)
  93{
  94        ide_drive_t *drive = to_ide_device(dev);
  95        ide_hwif_t *hwif = drive->hwif;
  96        unsigned long now;
  97        unsigned int msecs;
  98
  99        if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
 100                return -EOPNOTSUPP;
 101
 102        spin_lock_irq(&hwif->lock);
 103        now = jiffies;
 104        if (drive->dev_flags & IDE_DFLAG_PARKED &&
 105            time_after(drive->sleep, now))
 106                msecs = jiffies_to_msecs(drive->sleep - now);
 107        else
 108                msecs = 0;
 109        spin_unlock_irq(&hwif->lock);
 110
 111        return snprintf(buf, 20, "%u\n", msecs);
 112}
 113
 114ssize_t ide_park_store(struct device *dev, struct device_attribute *attr,
 115                       const char *buf, size_t len)
 116{
 117#define MAX_PARK_TIMEOUT 30000
 118        ide_drive_t *drive = to_ide_device(dev);
 119        long int input;
 120        int rc;
 121
 122        rc = kstrtol(buf, 10, &input);
 123        if (rc)
 124                return rc;
 125        if (input < -2)
 126                return -EINVAL;
 127        if (input > MAX_PARK_TIMEOUT) {
 128                input = MAX_PARK_TIMEOUT;
 129                rc = -EOVERFLOW;
 130        }
 131
 132        mutex_lock(&ide_setting_mtx);
 133        if (input >= 0) {
 134                if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
 135                        rc = -EOPNOTSUPP;
 136                else if (input || drive->dev_flags & IDE_DFLAG_PARKED)
 137                        issue_park_cmd(drive, msecs_to_jiffies(input));
 138        } else {
 139                if (drive->media == ide_disk)
 140                        switch (input) {
 141                        case -1:
 142                                drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD;
 143                                break;
 144                        case -2:
 145                                drive->dev_flags |= IDE_DFLAG_NO_UNLOAD;
 146                                break;
 147                        }
 148                else
 149                        rc = -EOPNOTSUPP;
 150        }
 151        mutex_unlock(&ide_setting_mtx);
 152
 153        return rc ? rc : len;
 154}
 155