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

   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
   8DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
   9
  10static 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_run_queue(q);
  31                return;
  32        }
  33        spin_unlock_irq(&hwif->lock);
  34
  35        rq = blk_get_request(q, REQ_OP_DRV_IN, __GFP_RECLAIM);
  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        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        elv_add_request(q, rq, ELEVATOR_INSERT_FRONT);
  58
  59out:
  60        return;
  61}
  62
  63ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
  64{
  65        struct ide_cmd cmd;
  66        struct ide_taskfile *tf = &cmd.tf;
  67
  68        memset(&cmd, 0, sizeof(cmd));
  69        if (scsi_req(rq)->cmd[0] == REQ_PARK_HEADS) {
  70                drive->sleep = *(unsigned long *)rq->special;
  71                drive->dev_flags |= IDE_DFLAG_SLEEPING;
  72                tf->command = ATA_CMD_IDLEIMMEDIATE;
  73                tf->feature = 0x44;
  74                tf->lbal = 0x4c;
  75                tf->lbam = 0x4e;
  76                tf->lbah = 0x55;
  77                cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
  78                cmd.valid.in.tf  = IDE_VALID_IN_TF  | IDE_VALID_DEVICE;
  79        } else          /* cmd == REQ_UNPARK_HEADS */
  80                tf->command = ATA_CMD_CHK_POWER;
  81
  82        cmd.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
  83        cmd.protocol = ATA_PROT_NODATA;
  84
  85        cmd.rq = rq;
  86
  87        return do_rw_taskfile(drive, &cmd);
  88}
  89
  90ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,
  91                      char *buf)
  92{
  93        ide_drive_t *drive = to_ide_device(dev);
  94        ide_hwif_t *hwif = drive->hwif;
  95        unsigned long now;
  96        unsigned int msecs;
  97
  98        if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
  99                return -EOPNOTSUPP;
 100
 101        spin_lock_irq(&hwif->lock);
 102        now = jiffies;
 103        if (drive->dev_flags & IDE_DFLAG_PARKED &&
 104            time_after(drive->sleep, now))
 105                msecs = jiffies_to_msecs(drive->sleep - now);
 106        else
 107                msecs = 0;
 108        spin_unlock_irq(&hwif->lock);
 109
 110        return snprintf(buf, 20, "%u\n", msecs);
 111}
 112
 113ssize_t ide_park_store(struct device *dev, struct device_attribute *attr,
 114                       const char *buf, size_t len)
 115{
 116#define MAX_PARK_TIMEOUT 30000
 117        ide_drive_t *drive = to_ide_device(dev);
 118        long int input;
 119        int rc;
 120
 121        rc = kstrtol(buf, 10, &input);
 122        if (rc)
 123                return rc;
 124        if (input < -2)
 125                return -EINVAL;
 126        if (input > MAX_PARK_TIMEOUT) {
 127                input = MAX_PARK_TIMEOUT;
 128                rc = -EOVERFLOW;
 129        }
 130
 131        mutex_lock(&ide_setting_mtx);
 132        if (input >= 0) {
 133                if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
 134                        rc = -EOPNOTSUPP;
 135                else if (input || drive->dev_flags & IDE_DFLAG_PARKED)
 136                        issue_park_cmd(drive, msecs_to_jiffies(input));
 137        } else {
 138                if (drive->media == ide_disk)
 139                        switch (input) {
 140                        case -1:
 141                                drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD;
 142                                break;
 143                        case -2:
 144                                drive->dev_flags |= IDE_DFLAG_NO_UNLOAD;
 145                                break;
 146                        }
 147                else
 148                        rc = -EOPNOTSUPP;
 149        }
 150        mutex_unlock(&ide_setting_mtx);
 151
 152        return rc ? rc : len;
 153}
 154