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
   7 DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
   8
   9 static 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 = rq->errors ? -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
  60 out:
  61         return;
  62 }
  63
  64 ide_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
  91 ssize_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
 114 ssize_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 }