root/drivers/ide/ide-park.c

DEFINITIONS

1. issue_park_cmd
2. ide_do_park_unpark
3. ide_park_show
4. ide_park_store

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/kernel.h>
   3 #include <linux/gfp.h>
   4 #include <linux/ide.h>
   5 #include <linux/jiffies.h>
   6 #include <linux/blkdev.h>
   7 
   8 DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
   9 
  10 static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout)
  11 {
  12         ide_hwif_t *hwif = drive->hwif;
  13         struct request_queue *q = drive->queue;
  14         struct request *rq;
  15         int rc;
  16 
  17         timeout += jiffies;
  18         spin_lock_irq(&hwif->lock);
  19         if (drive->dev_flags & IDE_DFLAG_PARKED) {
  20                 int reset_timer = time_before(timeout, drive->sleep);
  21                 int start_queue = 0;
  22 
  23                 drive->sleep = timeout;
  24                 wake_up_all(&ide_park_wq);
  25                 if (reset_timer && del_timer(&hwif->timer))
  26                         start_queue = 1;
  27                 spin_unlock_irq(&hwif->lock);
  28 
  29                 if (start_queue)
  30                         blk_mq_run_hw_queues(q, true);
  31                 return;
  32         }
  33         spin_unlock_irq(&hwif->lock);
  34 
  35         rq = blk_get_request(q, REQ_OP_DRV_IN, 0);
  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         ide_req(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, BLK_MQ_REQ_NOWAIT);
  51         if (IS_ERR(rq))
  52                 goto out;
  53 
  54         scsi_req(rq)->cmd[0] = REQ_UNPARK_HEADS;
  55         scsi_req(rq)->cmd_len = 1;
  56         ide_req(rq)->type = ATA_PRIV_MISC;
  57         spin_lock_irq(&hwif->lock);
  58         ide_insert_request_head(drive, rq);
  59         spin_unlock_irq(&hwif->lock);
  60 
  61 out:
  62         return;
  63 }
  64 
  65 ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
  66 {
  67         struct ide_cmd cmd;
  68         struct ide_taskfile *tf = &cmd.tf;
  69 
  70         memset(&cmd, 0, sizeof(cmd));
  71         if (scsi_req(rq)->cmd[0] == REQ_PARK_HEADS) {
  72                 drive->sleep = *(unsigned long *)ide_req(rq)->special;
  73                 drive->dev_flags |= IDE_DFLAG_SLEEPING;
  74                 tf->command = ATA_CMD_IDLEIMMEDIATE;
  75                 tf->feature = 0x44;
  76                 tf->lbal = 0x4c;
  77                 tf->lbam = 0x4e;
  78                 tf->lbah = 0x55;
  79                 cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
  80                 cmd.valid.in.tf  = IDE_VALID_IN_TF  | IDE_VALID_DEVICE;
  81         } else          /* cmd == REQ_UNPARK_HEADS */
  82                 tf->command = ATA_CMD_CHK_POWER;
  83 
  84         cmd.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
  85         cmd.protocol = ATA_PROT_NODATA;
  86 
  87         cmd.rq = rq;
  88 
  89         return do_rw_taskfile(drive, &cmd);
  90 }
  91 
  92 ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,
  93                       char *buf)
  94 {
  95         ide_drive_t *drive = to_ide_device(dev);
  96         ide_hwif_t *hwif = drive->hwif;
  97         unsigned long now;
  98         unsigned int msecs;
  99 
 100         if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
 101                 return -EOPNOTSUPP;
 102 
 103         spin_lock_irq(&hwif->lock);
 104         now = jiffies;
 105         if (drive->dev_flags & IDE_DFLAG_PARKED &&
 106             time_after(drive->sleep, now))
 107                 msecs = jiffies_to_msecs(drive->sleep - now);
 108         else
 109                 msecs = 0;
 110         spin_unlock_irq(&hwif->lock);
 111 
 112         return snprintf(buf, 20, "%u\n", msecs);
 113 }
 114 
 115 ssize_t ide_park_store(struct device *dev, struct device_attribute *attr,
 116                        const char *buf, size_t len)
 117 {
 118 #define MAX_PARK_TIMEOUT 30000
 119         ide_drive_t *drive = to_ide_device(dev);
 120         long int input;
 121         int rc;
 122 
 123         rc = kstrtol(buf, 10, &input);
 124         if (rc)
 125                 return rc;
 126         if (input < -2)
 127                 return -EINVAL;
 128         if (input > MAX_PARK_TIMEOUT) {
 129                 input = MAX_PARK_TIMEOUT;
 130                 rc = -EOVERFLOW;
 131         }
 132 
 133         mutex_lock(&ide_setting_mtx);
 134         if (input >= 0) {
 135                 if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
 136                         rc = -EOPNOTSUPP;
 137                 else if (input || drive->dev_flags & IDE_DFLAG_PARKED)
 138                         issue_park_cmd(drive, msecs_to_jiffies(input));
 139         } else {
 140                 if (drive->media == ide_disk)
 141                         switch (input) {
 142                         case -1:
 143                                 drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD;
 144                                 break;
 145                         case -2:
 146                                 drive->dev_flags |= IDE_DFLAG_NO_UNLOAD;
 147                                 break;
 148                         }
 149                 else
 150                         rc = -EOPNOTSUPP;
 151         }
 152         mutex_unlock(&ide_setting_mtx);
 153 
 154         return rc ? rc : len;
 155 }