#include <linux/kernel.h> #include <linux/ide.h> #include <linux/jiffies.h> #include <linux/blkdev.h> DECLARE_WAIT_QUEUE_HEAD(ide_park_wq); static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout) { ide_hwif_t *hwif = drive->hwif; struct request_queue *q = drive->queue; struct request *rq; int rc; timeout += jiffies; spin_lock_irq(&hwif->lock); if (drive->dev_flags & IDE_DFLAG_PARKED) { int reset_timer = time_before(timeout, drive->sleep); int start_queue = 0; drive->sleep = timeout; wake_up_all(&ide_park_wq); if (reset_timer && del_timer(&hwif->timer)) start_queue = 1; spin_unlock_irq(&hwif->lock); if (start_queue) { spin_lock_irq(q->queue_lock); blk_start_queueing(q); spin_unlock_irq(q->queue_lock); } return; } spin_unlock_irq(&hwif->lock); rq = blk_get_request(q, READ, __GFP_WAIT); rq->cmd[0] = REQ_PARK_HEADS; rq->cmd_len = 1; rq->cmd_type = REQ_TYPE_SPECIAL; rq->special = &timeout; rc = blk_execute_rq(q, NULL, rq, 1); blk_put_request(rq); if (rc) goto out; /* * Make sure that *some* command is sent to the drive after the * timeout has expired, so power management will be reenabled. */ rq = blk_get_request(q, READ, GFP_NOWAIT); if (unlikely(!rq)) goto out; rq->cmd[0] = REQ_UNPARK_HEADS; rq->cmd_len = 1; rq->cmd_type = REQ_TYPE_SPECIAL; elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 1); out: return; } ssize_t ide_park_show(struct device *dev, struct device_attribute *attr, char *buf) { ide_drive_t *drive = to_ide_device(dev); ide_hwif_t *hwif = drive->hwif; unsigned long now; unsigned int msecs; if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD) return -EOPNOTSUPP; spin_lock_irq(&hwif->lock); now = jiffies; if (drive->dev_flags & IDE_DFLAG_PARKED && time_after(drive->sleep, now)) msecs = jiffies_to_msecs(drive->sleep - now); else msecs = 0; spin_unlock_irq(&hwif->lock); return snprintf(buf, 20, "%u\n", msecs); } ssize_t ide_park_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { #define MAX_PARK_TIMEOUT 30000 ide_drive_t *drive = to_ide_device(dev); long int input; int rc; rc = strict_strtol(buf, 10, &input); if (rc || input < -2) return -EINVAL; if (input > MAX_PARK_TIMEOUT) { input = MAX_PARK_TIMEOUT; rc = -EOVERFLOW; } mutex_lock(&ide_setting_mtx); if (input >= 0) { if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD) rc = -EOPNOTSUPP; else if (input || drive->dev_flags & IDE_DFLAG_PARKED) issue_park_cmd(drive, msecs_to_jiffies(input)); } else { if (drive->media == ide_disk) switch (input) { case -1: drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD; break; case -2: drive->dev_flags |= IDE_DFLAG_NO_UNLOAD; break; } else rc = -EOPNOTSUPP; } mutex_unlock(&ide_setting_mtx); return rc ? rc : len; }